mirror of https://github.com/torvalds/linux.git
4054 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Shung-Hsi Yu
|
1ae497c78f |
bpf: use type_may_be_null() helper for nullable-param check
Commit |
|
Martin KaFai Lau
|
00750788df |
bpf: Fix indentation issue in epilogue_idx
There is a report on new indentation issue in epilogue_idx.
This patch fixed it.
Fixes:
|
|
|
Martin KaFai Lau
|
940ce73bde |
bpf: Remove the insn_buf array stack usage from the inline_bpf_loop()
This patch removes the insn_buf array stack usage from the inline_bpf_loop(). Instead, the env->insn_buf is used. The usage in inline_bpf_loop() needs more than 16 insn, so the INSN_BUF_SIZE needs to be increased from 16 to 32. The compiler stack size warning on the verifier is gone after this change. Cc: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20240904180847.56947-2-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Jeongjun Park
|
bb6705c3f9 |
bpf: add check for invalid name in btf_name_valid_section()
If the length of the name string is 1 and the value of name[0] is NULL
byte, an OOB vulnerability occurs in btf_name_valid_section() and the
return value is true, so the invalid name passes the check.
To solve this, you need to check if the first position is NULL byte and
if the first character is printable.
Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Fixes:
|
|
|
Martin KaFai Lau
|
b408473ea0 |
bpf: Fix a crash when btf_parse_base() returns an error pointer
The pointer returned by btf_parse_base could be an error pointer.
IS_ERR() check is needed before calling btf_free(base_btf).
Fixes:
|
|
Jinjie Ruan
|
65ef66d918 |
bpf: Use sockfd_put() helper
Replace fput() with sockfd_put() in bpf_fd_reuseport_array_update_elem(). Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> Acked-by: Stanislav Fomichev <sdf@fomichev.me> Link: https://lore.kernel.org/r/20240830020756.607877-1-ruanjinjie@huawei.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Alexey Gladkov
|
1dd7622ef5 |
bpf: Remove custom build rule
According to the documentation, when building a kernel with the C=2 parameter, all source files should be checked. But this does not happen for the kernel/bpf/ directory. $ touch kernel/bpf/core.o $ make C=2 CHECK=true kernel/bpf/core.o Outputs: CHECK scripts/mod/empty.c CALL scripts/checksyscalls.sh DESCEND objtool INSTALL libsubcmd_headers CC kernel/bpf/core.o As can be seen the compilation is done, but CHECK is not executed. This happens because kernel/bpf/Makefile has defined its own rule for compilation and forgotten the macro that does the check. There is no need to duplicate the build code, and this rule can be removed to use generic rules. Acked-by: Masahiro Yamada <masahiroy@kernel.org> Tested-by: Oleg Nesterov <oleg@redhat.com> Tested-by: Alan Maguire <alan.maguire@oracle.com> Signed-off-by: Alexey Gladkov <legion@kernel.org> Link: https://lore.kernel.org/r/20240830074350.211308-1-legion@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Juntong Deng
|
4cc8c50c9a |
bpf: Make the pointer returned by iter next method valid
Currently we cannot pass the pointer returned by iter next method as argument to KF_TRUSTED_ARGS or KF_RCU kfuncs, because the pointer returned by iter next method is not "valid". This patch sets the pointer returned by iter next method to be valid. This is based on the fact that if the iterator is implemented correctly, then the pointer returned from the iter next method should be valid. This does not make NULL pointer valid. If the iter next method has KF_RET_NULL flag, then the verifier will ask the ebpf program to check NULL pointer. KF_RCU_PROTECTED iterator is a special case, the pointer returned by iter next method should only be valid within RCU critical section, so it should be with MEM_RCU, not PTR_TRUSTED. Another special case is bpf_iter_num_next, which returns a pointer with base type PTR_TO_MEM. PTR_TO_MEM should not be combined with type flag PTR_TRUSTED (PTR_TO_MEM already means the pointer is valid). The pointer returned by iter next method of other types of iterators is with PTR_TRUSTED. In addition, this patch adds get_iter_from_state to help us get the current iterator from the current state. Signed-off-by: Juntong Deng <juntong.deng@outlook.com> Link: https://lore.kernel.org/r/AM6PR03MB584869F8B448EA1C87B7CDA399962@AM6PR03MB5848.eurprd03.prod.outlook.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Martin KaFai Lau
|
866d571e62 |
bpf: Export bpf_base_func_proto
The bpf_testmod needs to use the bpf_tail_call helper in a later selftest patch. This patch is to EXPORT_GPL_SYMBOL the bpf_base_func_proto. Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20240829210833.388152-5-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Martin KaFai Lau
|
169c31761c |
bpf: Add gen_epilogue to bpf_verifier_ops
This patch adds a .gen_epilogue to the bpf_verifier_ops. It is similar to the existing .gen_prologue. Instead of allowing a subsystem to run code at the beginning of a bpf prog, it allows the subsystem to run code just before the bpf prog exit. One of the use case is to allow the upcoming bpf qdisc to ensure that the skb->dev is the same as the qdisc->dev_queue->dev. The bpf qdisc struct_ops implementation could either fix it up or drop the skb. Another use case could be in bpf_tcp_ca.c to enforce snd_cwnd has sane value (e.g. non zero). The epilogue can do the useful thing (like checking skb->dev) if it can access the bpf prog's ctx. Unlike prologue, r1 may not hold the ctx pointer. This patch saves the r1 in the stack if the .gen_epilogue has returned some instructions in the "epilogue_buf". The existing .gen_prologue is done in convert_ctx_accesses(). The new .gen_epilogue is done in the convert_ctx_accesses() also. When it sees the (BPF_JMP | BPF_EXIT) instruction, it will be patched with the earlier generated "epilogue_buf". The epilogue patching is only done for the main prog. Only one epilogue will be patched to the main program. When the bpf prog has multiple BPF_EXIT instructions, a BPF_JA is used to goto the earlier patched epilogue. Majority of the archs support (BPF_JMP32 | BPF_JA): x86, arm, s390, risv64, loongarch, powerpc and arc. This patch keeps it simple and always use (BPF_JMP32 | BPF_JA). A new macro BPF_JMP32_A is added to generate the (BPF_JMP32 | BPF_JA) insn. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20240829210833.388152-4-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Martin KaFai Lau
|
d5c47719f2 |
bpf: Adjust BPF_JMP that jumps to the 1st insn of the prologue
The next patch will add a ctx ptr saving instruction
"(r1 = *(u64 *)(r10 -8)" at the beginning for the main prog
when there is an epilogue patch (by the .gen_epilogue() verifier
ops added in the next patch).
There is one corner case if the bpf prog has a BPF_JMP that jumps
to the 1st instruction. It needs an adjustment such that
those BPF_JMP instructions won't jump to the newly added
ctx saving instruction.
The commit
|
|
|
Martin KaFai Lau
|
6f606ffd6d |
bpf: Move insn_buf[16] to bpf_verifier_env
This patch moves the 'struct bpf_insn insn_buf[16]' stack usage to the bpf_verifier_env. A '#define INSN_BUF_SIZE 16' is also added to replace the ARRAY_SIZE(insn_buf) usages. Both convert_ctx_accesses() and do_misc_fixup() are changed to use the env->insn_buf. It is a refactoring work for adding the epilogue_buf[16] in a later patch. With this patch, the stack size usage decreased. Before: ./kernel/bpf/verifier.c:22133:5: warning: stack frame size (2584) After: ./kernel/bpf/verifier.c:22184:5: warning: stack frame size (2264) Reviewed-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20240829210833.388152-2-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Hongbo Li
|
c6d9dafb59 |
bpf: Use kvmemdup to simplify the code
Use kvmemdup instead of kvmalloc() + memcpy() to simplify the code. No functional change intended. Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Hongbo Li <lihongbo22@huawei.com> Link: https://lore.kernel.org/r/20240828062128.1223417-1-lihongbo22@huawei.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Juntong Deng
|
f633919d13 |
bpf: Relax KF_ACQUIRE kfuncs strict type matching constraint
Currently we cannot pass zero offset (implicit cast) or non-zero offset pointers to KF_ACQUIRE kfuncs. This is because KF_ACQUIRE kfuncs requires strict type matching, but zero offset or non-zero offset does not change the type of pointer, which causes the ebpf program to be rejected by the verifier. This can cause some problems, one example is that bpf_skb_peek_tail kfunc [0] cannot be implemented by just passing in non-zero offset pointers. We cannot pass pointers like &sk->sk_write_queue (non-zero offset) or &sk->__sk_common (zero offset) to KF_ACQUIRE kfuncs. This patch makes KF_ACQUIRE kfuncs not require strict type matching. [0]: https://lore.kernel.org/bpf/AM6PR03MB5848CA39CB4B7A4397D380B099B12@AM6PR03MB5848.eurprd03.prod.outlook.com/ Signed-off-by: Juntong Deng <juntong.deng@outlook.com> Link: https://lore.kernel.org/r/AM6PR03MB5848FD2BD89BF0B6B5AA3B4C99952@AM6PR03MB5848.eurprd03.prod.outlook.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Jordan Rome
|
65ab5ac4df |
bpf: Add bpf_copy_from_user_str kfunc
This adds a kfunc wrapper around strncpy_from_user, which can be called from sleepable BPF programs. This matches the non-sleepable 'bpf_probe_read_user_str' helper except it includes an additional 'flags' param, which allows consumers to clear the entire destination buffer on success or failure. Signed-off-by: Jordan Rome <linux@jordanrome.com> Link: https://lore.kernel.org/r/20240823195101.3621028-1-linux@jordanrome.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Dave Marchevsky
|
b0966c7245 |
bpf: Support bpf_kptr_xchg into local kptr
Currently, users can only stash kptr into map values with bpf_kptr_xchg(). This patch further supports stashing kptr into local kptr by adding local kptr as a valid destination type. When stashing into local kptr, btf_record in program BTF is used instead of btf_record in map to search for the btf_field of the local kptr. The local kptr specific checks in check_reg_type() only apply when the source argument of bpf_kptr_xchg() is local kptr. Therefore, we make the scope of the check explicit as the destination now can also be local kptr. Acked-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> Signed-off-by: Amery Hung <amery.hung@bytedance.com> Link: https://lore.kernel.org/r/20240813212424.2871455-5-amery.hung@bytedance.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Dave Marchevsky
|
d59232afb0 |
bpf: Rename ARG_PTR_TO_KPTR -> ARG_KPTR_XCHG_DEST
ARG_PTR_TO_KPTR is currently only used by the bpf_kptr_xchg helper. Although it limits reg types for that helper's first arg to PTR_TO_MAP_VALUE, any arbitrary mapval won't do: further custom verification logic ensures that the mapval reg being xchgd-into is pointing to a kptr field. If this is not the case, it's not safe to xchg into that reg's pointee. Let's rename the bpf_arg_type to more accurately describe the fairly specific expectations that this arg type encodes. This is a nonfunctional change. Acked-by: Martin KaFai Lau <martin.lau@kernel.org> Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> Signed-off-by: Amery Hung <amery.hung@bytedance.com> Link: https://lore.kernel.org/r/20240813212424.2871455-4-amery.hung@bytedance.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Dave Marchevsky
|
7a851ecb18 |
bpf: Search for kptrs in prog BTF structs
Currently btf_parse_fields is used in two places to create struct
btf_record's for structs: when looking at mapval type, and when looking
at any struct in program BTF. The former looks for kptr fields while the
latter does not. This patch modifies the btf_parse_fields call made when
looking at prog BTF struct types to search for kptrs as well.
Before this series there was no reason to search for kptrs in non-mapval
types: a referenced kptr needs some owner to guarantee resource cleanup,
and map values were the only owner that supported this. If a struct with
a kptr field were to have some non-kptr-aware owner, the kptr field
might not be properly cleaned up and result in resources leaking. Only
searching for kptr fields in mapval was a simple way to avoid this
problem.
In practice, though, searching for BPF_KPTR when populating
struct_meta_tab does not expose us to this risk, as struct_meta_tab is
only accessed through btf_find_struct_meta helper, and that helper is
only called in contexts where recognizing the kptr field is safe:
* PTR_TO_BTF_ID reg w/ MEM_ALLOC flag
* Such a reg is a local kptr and must be free'd via bpf_obj_drop,
which will correctly handle kptr field
* When handling specific kfuncs which either expect MEM_ALLOC input or
return MEM_ALLOC output (obj_{new,drop}, percpu_obj_{new,drop},
list+rbtree funcs, refcount_acquire)
* Will correctly handle kptr field for same reasons as above
* When looking at kptr pointee type
* Called by functions which implement "correct kptr resource
handling"
* In btf_check_and_fixup_fields
* Helper that ensures no ownership loops for lists and rbtrees,
doesn't care about kptr field existence
So we should be able to find BPF_KPTR fields in all prog BTF structs
without leaking resources.
Further patches in the series will build on this change to support
kptr_xchg into non-mapval local kptr. Without this change there would be
no kptr field found in such a type.
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Acked-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Signed-off-by: Amery Hung <amery.hung@bytedance.com>
Link: https://lore.kernel.org/r/20240813212424.2871455-3-amery.hung@bytedance.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
Amery Hung
|
c5ef53420f |
bpf: Let callers of btf_parse_kptr() track life cycle of prog btf
btf_parse_kptr() and btf_record_free() do btf_get() and btf_put() respectively when working on btf_record in program and map if there are kptr fields. If the kptr is from program BTF, since both callers has already tracked the life cycle of program BTF, it is safe to remove the btf_get() and btf_put(). This change prevents memory leak of program BTF later when we start searching for kptr fields when building btf_record for program. It can happen when the btf fd is closed. The btf_put() corresponding to the btf_get() in btf_parse_kptr() was supposed to be called by btf_record_free() in btf_free_struct_meta_tab() in btf_free(). However, it will never happen since the invocation of btf_free() depends on the refcount of the btf to become 0 in the first place. Acked-by: Martin KaFai Lau <martin.lau@kernel.org> Acked-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Amery Hung <amery.hung@bytedance.com> Link: https://lore.kernel.org/r/20240813212424.2871455-2-amery.hung@bytedance.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Alexei Starovoitov
|
50c374c6d1 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf
Cross-merge bpf fixes after downstream PR including important fixes (from bpf-next point of view): commit |
|
Eduard Zingerman
|
4060909324 |
bpf: allow bpf_fastcall for bpf_cast_to_kern_ctx and bpf_rdonly_cast
do_misc_fixups() relaces bpf_cast_to_kern_ctx() and bpf_rdonly_cast() by a single instruction "r0 = r1". This follows bpf_fastcall contract. This commit allows bpf_fastcall pattern rewrite for these two functions in order to use them in bpf_fastcall selftests. Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240822084112.3257995-5-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Eduard Zingerman
|
b2ee6d27e9 |
bpf: support bpf_fastcall patterns for kfuncs
Recognize bpf_fastcall patterns around kfunc calls. For example, suppose bpf_cast_to_kern_ctx() follows bpf_fastcall contract (which it does), in such a case allow verifier to rewrite BPF program below: r2 = 1; *(u64 *)(r10 - 32) = r2; call %[bpf_cast_to_kern_ctx]; r2 = *(u64 *)(r10 - 32); r0 = r2; By removing the spill/fill pair: r2 = 1; call %[bpf_cast_to_kern_ctx]; r0 = r2; Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240822084112.3257995-4-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Eduard Zingerman
|
ae010757a5 |
bpf: rename nocsr -> bpf_fastcall in verifier
Attribute used by LLVM implementation of the feature had been changed from no_caller_saved_registers to bpf_fastcall (see [1]). This commit replaces references to nocsr by references to bpf_fastcall to keep LLVM and Kernel parts in sync. [1] https://github.com/llvm/llvm-project/pull/105417 Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240822084112.3257995-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Uros Bizjak
|
6d641ca50d |
bpf: Fix percpu address space issues
In arraymap.c: In bpf_array_map_seq_start() and bpf_array_map_seq_next() cast return values from the __percpu address space to the generic address space via uintptr_t [1]. Correct the declaration of pptr pointer in __bpf_array_map_seq_show() to void __percpu * and cast the value from the generic address space to the __percpu address space via uintptr_t [1]. In hashtab.c: Assign the return value from bpf_mem_cache_alloc() to void pointer and cast the value to void __percpu ** (void pointer to percpu void pointer) before dereferencing. In memalloc.c: Explicitly declare __percpu variables. Cast obj to void __percpu **. In helpers.c: Cast ptr in BPF_CALL_1 and BPF_CALL_2 from generic address space to __percpu address space via const uintptr_t [1]. Found by GCC's named address space checks. There were no changes in the resulting object files. [1] https://sparse.docs.kernel.org/en/latest/annotations.html#address-space-name Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Song Liu <song@kernel.org> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Stanislav Fomichev <sdf@fomichev.me> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240811161414.56744-1-ubizjak@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Eduard Zingerman
|
3d2786d65a |
bpf: correctly handle malformed BPF_CORE_TYPE_ID_LOCAL relos
In case of malformed relocation record of kind BPF_CORE_TYPE_ID_LOCAL
referencing a non-existing BTF type, function bpf_core_calc_relo_insn
would cause a null pointer deference.
Fix this by adding a proper check upper in call stack, as malformed
relocation records could be passed from user space.
Simplest reproducer is a program:
r0 = 0
exit
With a single relocation record:
.insn_off = 0, /* patch first instruction */
.type_id = 100500, /* this type id does not exist */
.access_str_off = 6, /* offset of string "0" */
.kind = BPF_CORE_TYPE_ID_LOCAL,
See the link for original reproducer or next commit for a test case.
Fixes:
|
|
Andrii Nakryiko
|
baebe9aaba |
bpf: allow passing struct bpf_iter_<type> as kfunc arguments
There are potentially useful cases where a specific iterator type might
need to be passed into some kfunc. So, in addition to existing
bpf_iter_<type>_{new,next,destroy}() kfuncs, allow to pass iterator
pointer to any kfunc.
We employ "__iter" naming suffix for arguments that are meant to accept
iterators. We also enforce that they accept PTR -> STRUCT btf_iter_<type>
type chain and point to a valid initialized on-the-stack iterator state.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240808232230.2848712-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
496ddd19a0 |
bpf: extract iterator argument type and name validation logic
Verifier enforces that all iterator structs are named `bpf_iter_<name>` and that whenever iterator is passed to a kfunc it's passed as a valid PTR -> STRUCT chain (with potentially const modifiers in between). We'll need this check for upcoming changes, so instead of duplicating the logic, extract it into a helper function. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240808232230.2848712-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Matteo Croce
|
7f6287417b |
bpf: Allow bpf_current_task_under_cgroup() with BPF_CGROUP_*
The helper bpf_current_task_under_cgroup() currently is only allowed for tracing programs, allow its usage also in the BPF_CGROUP_* program types. Move the code from kernel/trace/bpf_trace.c to kernel/bpf/helpers.c, so it compiles also without CONFIG_BPF_EVENTS. This will be used in systemd-networkd to monitor the sysctl writes, and filter it's own writes from others: https://github.com/systemd/systemd/pull/32212 Signed-off-by: Matteo Croce <teknoraver@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240819162805.78235-3-technoboy85@gmail.com |
|
|
Matteo Croce
|
67666479ed |
bpf: Enable generic kfuncs for BPF_CGROUP_* programs
These kfuncs are enabled even in BPF_PROG_TYPE_TRACING, so they should be safe also in BPF_CGROUP_* programs. Since all BPF_CGROUP_* programs share the same hook, call register_btf_kfunc_id_set() only once. In enum btf_kfunc_hook, rename BTF_KFUNC_HOOK_CGROUP_SKB to a more generic BTF_KFUNC_HOOK_CGROUP, since it's used for all the cgroup related program types. Signed-off-by: Matteo Croce <teknoraver@meta.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240819162805.78235-2-technoboy85@gmail.com |
|
|
Jeongjun Park
|
febb6f3e3a |
bpf: Remove __btf_name_valid() and change to btf_name_valid_identifier()
__btf_name_valid() can be completely replaced with btf_name_valid_identifier, and since most of the time you already call btf_name_valid_identifier instead of __btf_name_valid , it would be appropriate to rename the __btf_name_valid function to btf_name_valid_identifier and remove __btf_name_valid. Signed-off-by: Jeongjun Park <aha310510@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Alan Maguire <alan.maguire@oracle.com> Link: https://lore.kernel.org/bpf/20240807143110.181497-1-aha310510@gmail.com |
|
Al Viro
|
eceb7b33e5 |
bpf: more trivial fdget() conversions
All failure exits prior to fdget() leave the scope, all matching fdput() are immediately followed by leaving the scope. Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Al Viro
|
eb80ee8580 |
bpf: trivial conversions for fdget()
fdget() is the first thing done in scope, all matching fdput() are immediately followed by leaving the scope. Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Al Viro
|
55f325958c |
bpf: switch maps to CLASS(fd, ...)
Calling conventions for __bpf_map_get() would be more convenient if it left fpdut() on failure to callers. Makes for simpler logics in the callers. Among other things, the proof of memory safety no longer has to rely upon file->private_data never being ERR_PTR(...) for bpffs files. Original calling conventions made it impossible for the caller to tell whether __bpf_map_get() has returned ERR_PTR(-EINVAL) because it has found the file not be a bpf map one (in which case it would've done fdput()) or because it found that ERR_PTR(-EINVAL) in file->private_data of a bpf map file (in which case fdput() would _not_ have been done). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Andrii Nakryiko
|
535ead44ff |
bpf: factor out fetching bpf_map from FD and adding it to used_maps list
Factor out the logic to extract bpf_map instances from FD embedded in bpf_insns, adding it to the list of used_maps (unless it's already there, in which case we just reuse map's index). This simplifies the logic in resolve_pseudo_ldimm64(), especially around `struct fd` handling, as all that is now neatly contained in the helper and doesn't leak into a dozen error handling paths. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Al Viro
|
51a1ca933f |
bpf: switch fdget_raw() uses to CLASS(fd_raw, ...)
Swith fdget_raw() use cases in bpf_inode_storage.c to CLASS(fd_raw). Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Al Viro
|
d71973707e |
bpf: convert __bpf_prog_get() to CLASS(fd, ...)
Irregularity here is fdput() not in the same scope as fdget(); just fold ____bpf_prog_get() into its (only) caller and that's it... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Andrii Nakryiko
|
50470d3899 |
Merge remote-tracking branch 'vfs/stable-struct_fd'
Merge Al Viro's struct fd refactorings. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Al Viro
|
1da91ea87a |
introduce fd_file(), convert all accessors to it.
For any changes of struct fd representation we need to
turn existing accesses to fields into calls of wrappers.
Accesses to struct fd::flags are very few (3 in linux/file.h,
1 in net/socket.c, 3 in fs/overlayfs/file.c and 3 more in
explicit initializers).
Those can be dealt with in the commit converting to
new layout; accesses to struct fd::file are too many for that.
This commit converts (almost) all of f.file to
fd_file(f). It's not entirely mechanical ('file' is used as
a member name more than just in struct fd) and it does not
even attempt to distinguish the uses in pointer context from
those in boolean context; the latter will be eventually turned
into a separate helper (fd_empty()).
NOTE: mass conversion to fd_empty(), tempting as it
might be, is a bad idea; better do that piecewise in commit
that convert from fdget...() to CLASS(...).
[conflicts in fs/fhandle.c, kernel/bpf/syscall.c, mm/memcontrol.c
caught by git; fs/stat.c one got caught by git grep]
[fs/xattr.c conflict]
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
|
Yonghong Song
|
bed2eb964c |
bpf: Fix a kernel verifier crash in stacksafe()
Daniel Hodges reported a kernel verifier crash when playing with sched-ext.
Further investigation shows that the crash is due to invalid memory access
in stacksafe(). More specifically, it is the following code:
if (exact != NOT_EXACT &&
old->stack[spi].slot_type[i % BPF_REG_SIZE] !=
cur->stack[spi].slot_type[i % BPF_REG_SIZE])
return false;
The 'i' iterates old->allocated_stack.
If cur->allocated_stack < old->allocated_stack the out-of-bound
access will happen.
To fix the issue add 'i >= cur->allocated_stack' check such that if
the condition is true, stacksafe() should fail. Otherwise,
cur->stack[spi].slot_type[i % BPF_REG_SIZE] memory access is legal.
Fixes:
|
|
|
Eduard Zingerman
|
91b7fbf393 |
bpf, x86, riscv, arm: no_caller_saved_registers for bpf_get_smp_processor_id()
The function bpf_get_smp_processor_id() is processed in a different way, depending on the arch: - on x86 verifier replaces call to bpf_get_smp_processor_id() with a sequence of instructions that modify only r0; - on riscv64 jit replaces call to bpf_get_smp_processor_id() with a sequence of instructions that modify only r0; - on arm64 jit replaces call to bpf_get_smp_processor_id() with a sequence of instructions that modify only r0 and tmp registers. These rewrites satisfy attribute no_caller_saved_registers contract. Allow rewrite of no_caller_saved_registers patterns for bpf_get_smp_processor_id() in order to use this function as a canary for no_caller_saved_registers tests. Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240722233844.1406874-4-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Eduard Zingerman
|
5b5f51bff1 |
bpf: no_caller_saved_registers attribute for helper calls
GCC and LLVM define a no_caller_saved_registers function attribute.
This attribute means that function scratches only some of
the caller saved registers defined by ABI.
For BPF the set of such registers could be defined as follows:
- R0 is scratched only if function is non-void;
- R1-R5 are scratched only if corresponding parameter type is defined
in the function prototype.
This commit introduces flag bpf_func_prot->allow_nocsr.
If this flag is set for some helper function, verifier assumes that
it follows no_caller_saved_registers calling convention.
The contract between kernel and clang allows to simultaneously use
such functions and maintain backwards compatibility with old
kernels that don't understand no_caller_saved_registers calls
(nocsr for short):
- clang generates a simple pattern for nocsr calls, e.g.:
r1 = 1;
r2 = 2;
*(u64 *)(r10 - 8) = r1;
*(u64 *)(r10 - 16) = r2;
call %[to_be_inlined]
r2 = *(u64 *)(r10 - 16);
r1 = *(u64 *)(r10 - 8);
r0 = r1;
r0 += r2;
exit;
- kernel removes unnecessary spills and fills, if called function is
inlined by verifier or current JIT (with assumption that patch
inserted by verifier or JIT honors nocsr contract, e.g. does not
scratch r3-r5 for the example above), e.g. the code above would be
transformed to:
r1 = 1;
r2 = 2;
call %[to_be_inlined]
r0 = r1;
r0 += r2;
exit;
Technically, the transformation is split into the following phases:
- function mark_nocsr_patterns(), called from bpf_check()
searches and marks potential patterns in instruction auxiliary data;
- upon stack read or write access,
function check_nocsr_stack_contract() is used to verify if
stack offsets, presumably reserved for nocsr patterns, are used
only from those patterns;
- function remove_nocsr_spills_fills(), called from bpf_check(),
applies the rewrite for valid patterns.
See comment in mark_nocsr_pattern_for_call() for more details.
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240722233844.1406874-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
|
|
|
Eduard Zingerman
|
45cbc7a5e0 |
bpf: add a get_helper_proto() utility function
Extract the part of check_helper_call() as a utility function allowing to query 'struct bpf_func_proto' for a specific helper function id. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240722233844.1406874-2-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Yonghong Song
|
9f5469b845 |
bpf: Get better reg range with ldsx and 32bit compare
With latest llvm19, the selftest iters/iter_arr_with_actual_elem_count
failed with -mcpu=v4.
The following are the details:
0: R1=ctx() R10=fp0
; int iter_arr_with_actual_elem_count(const void *ctx) @ iters.c:1420
0: (b4) w7 = 0 ; R7_w=0
; int i, n = loop_data.n, sum = 0; @ iters.c:1422
1: (18) r1 = 0xffffc90000191478 ; R1_w=map_value(map=iters.bss,ks=4,vs=1280,off=1144)
3: (61) r6 = *(u32 *)(r1 +128) ; R1_w=map_value(map=iters.bss,ks=4,vs=1280,off=1144) R6_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff))
; if (n > ARRAY_SIZE(loop_data.data)) @ iters.c:1424
4: (26) if w6 > 0x20 goto pc+27 ; R6_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f))
5: (bf) r8 = r10 ; R8_w=fp0 R10=fp0
6: (07) r8 += -8 ; R8_w=fp-8
; bpf_for(i, 0, n) { @ iters.c:1427
7: (bf) r1 = r8 ; R1_w=fp-8 R8_w=fp-8
8: (b4) w2 = 0 ; R2_w=0
9: (bc) w3 = w6 ; R3_w=scalar(id=1,smin=smin32=0,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f)) R6_w=scalar(id=1,smin=smin32=0,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f))
10: (85) call bpf_iter_num_new#45179 ; R0=scalar() fp-8=iter_num(ref_id=2,state=active,depth=0) refs=2
11: (bf) r1 = r8 ; R1=fp-8 R8=fp-8 refs=2
12: (85) call bpf_iter_num_next#45181 13: R0=rdonly_mem(id=3,ref_obj_id=2,sz=4) R6=scalar(id=1,smin=smin32=0,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f)) R7=0 R8=fp-8 R10=fp0 fp-8=iter_num(ref_id=2,state=active,depth=1) refs=2
; bpf_for(i, 0, n) { @ iters.c:1427
13: (15) if r0 == 0x0 goto pc+2 ; R0=rdonly_mem(id=3,ref_obj_id=2,sz=4) refs=2
14: (81) r1 = *(s32 *)(r0 +0) ; R0=rdonly_mem(id=3,ref_obj_id=2,sz=4) R1_w=scalar(smin=0xffffffff80000000,smax=0x7fffffff) refs=2
15: (ae) if w1 < w6 goto pc+4 20: R0=rdonly_mem(id=3,ref_obj_id=2,sz=4) R1=scalar(smin=0xffffffff80000000,smax=smax32=umax32=31,umax=0xffffffff0000001f,smin32=0,var_off=(0x0; 0xffffffff0000001f)) R6=scalar(id=1,smin=umin=smin32=umin32=1,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f)) R7=0 R8=fp-8 R10=fp0 fp-8=iter_num(ref_id=2,state=active,depth=1) refs=2
; sum += loop_data.data[i]; @ iters.c:1429
20: (67) r1 <<= 2 ; R1_w=scalar(smax=0x7ffffffc0000007c,umax=0xfffffffc0000007c,smin32=0,smax32=umax32=124,var_off=(0x0; 0xfffffffc0000007c)) refs=2
21: (18) r2 = 0xffffc90000191478 ; R2_w=map_value(map=iters.bss,ks=4,vs=1280,off=1144) refs=2
23: (0f) r2 += r1
math between map_value pointer and register with unbounded min value is not allowed
The source code:
int iter_arr_with_actual_elem_count(const void *ctx)
{
int i, n = loop_data.n, sum = 0;
if (n > ARRAY_SIZE(loop_data.data))
return 0;
bpf_for(i, 0, n) {
/* no rechecking of i against ARRAY_SIZE(loop_data.n) */
sum += loop_data.data[i];
}
return sum;
}
The insn #14 is a sign-extenstion load which is related to 'int i'.
The insn #15 did a subreg comparision. Note that smin=0xffffffff80000000 and this caused later
insn #23 failed verification due to unbounded min value.
Actually insn #15 R1 smin range can be better. Before insn #15, we have
R1_w=scalar(smin=0xffffffff80000000,smax=0x7fffffff)
With the above range, we know for R1, upper 32bit can only be 0xffffffff or 0.
Otherwise, the value range for R1 could be beyond [smin=0xffffffff80000000,smax=0x7fffffff].
After insn #15, for the true patch, we know smin32=0 and smax32=32. With the upper 32bit 0xffffffff,
then the corresponding value is [0xffffffff00000000, 0xffffffff00000020]. The range is
obviously beyond the original range [smin=0xffffffff80000000,smax=0x7fffffff] and the
range is not possible. So the upper 32bit must be 0, which implies smin = smin32 and
smax = smax32.
This patch fixed the issue by adding additional register deduction after 32-bit compare
insn. If the signed 32-bit register range is non-negative then 64-bit smin is
in range of [S32_MIN, S32_MAX], then the actual 64-bit smin/smax should be the same
as 32-bit smin32/smax32.
With this patch, iters/iter_arr_with_actual_elem_count succeeded with better register range:
from 15 to 20: R0=rdonly_mem(id=7,ref_obj_id=2,sz=4) R1_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=31,var_off=(0x0; 0x1f)) R6=scalar(id=1,smin=umin=smin32=umin32=1,smax=umax=smax32=umax32=32,var_off=(0x0; 0x3f)) R7=scalar(id=9,smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) R8=scalar(id=9,smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) R10=fp0 fp-8=iter_num(ref_id=2,state=active,depth=3) refs=2
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240723162933.2731620-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
|
|
|
Yonghong Song
|
92de36080c |
bpf: Fail verification for sign-extension of packet data/data_end/data_meta
syzbot reported a kernel crash due to commit |
|
Xu Kuohai
|
763aa759d3 |
bpf: Fix compare error in function retval_range_within
After checking lsm hook return range in verifier, the test case
"test_progs -t test_lsm" failed, and the failure log says:
libbpf: prog 'test_int_hook': BPF program load failed: Invalid argument
libbpf: prog 'test_int_hook': -- BEGIN PROG LOAD LOG --
0: R1=ctx() R10=fp0
; int BPF_PROG(test_int_hook, struct vm_area_struct *vma, @ lsm.c:89
0: (79) r0 = *(u64 *)(r1 +24) ; R0_w=scalar(smin=smin32=-4095,smax=smax32=0) R1=ctx()
[...]
24: (b4) w0 = -1 ; R0_w=0xffffffff
; int BPF_PROG(test_int_hook, struct vm_area_struct *vma, @ lsm.c:89
25: (95) exit
At program exit the register R0 has smin=4294967295 smax=4294967295 should have been in [-4095, 0]
It can be seen that instruction "w0 = -1" zero extended -1 to 64-bit
register r0, setting both smin and smax values of r0 to 4294967295.
This resulted in a false reject when r0 was checked with range [-4095, 0].
Given bpf lsm does not return 64-bit values, this patch fixes it by changing
the compare between r0 and return range from 64-bit operation to 32-bit
operation for bpf lsm.
Fixes:
|
|
|
Xu Kuohai
|
28ead3eaab |
bpf: Prevent tail call between progs attached to different hooks
bpf progs can be attached to kernel functions, and the attached functions can take different parameters or return different return values. If prog attached to one kernel function tail calls prog attached to another kernel function, the ctx access or return value verification could be bypassed. For example, if prog1 is attached to func1 which takes only 1 parameter and prog2 is attached to func2 which takes two parameters. Since verifier assumes the bpf ctx passed to prog2 is constructed based on func2's prototype, verifier allows prog2 to access the second parameter from the bpf ctx passed to it. The problem is that verifier does not prevent prog1 from passing its bpf ctx to prog2 via tail call. In this case, the bpf ctx passed to prog2 is constructed from func1 instead of func2, that is, the assumption for ctx access verification is bypassed. Another example, if BPF LSM prog1 is attached to hook file_alloc_security, and BPF LSM prog2 is attached to hook bpf_lsm_audit_rule_known. Verifier knows the return value rules for these two hooks, e.g. it is legal for bpf_lsm_audit_rule_known to return positive number 1, and it is illegal for file_alloc_security to return positive number. So verifier allows prog2 to return positive number 1, but does not allow prog1 to return positive number. The problem is that verifier does not prevent prog1 from calling prog2 via tail call. In this case, prog2's return value 1 will be used as the return value for prog1's hook file_alloc_security. That is, the return value rule is bypassed. This patch adds restriction for tail call to prevent such bypasses. Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Link: https://lore.kernel.org/r/20240719110059.797546-4-xukuohai@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Xu Kuohai
|
5d99e198be |
bpf, lsm: Add check for BPF LSM return value
A bpf prog returning a positive number attached to file_alloc_security
hook makes kernel panic.
This happens because file system can not filter out the positive number
returned by the LSM prog using IS_ERR, and misinterprets this positive
number as a file pointer.
Given that hook file_alloc_security never returned positive number
before the introduction of BPF LSM, and other BPF LSM hooks may
encounter similar issues, this patch adds LSM return value check
in verifier, to ensure no unexpected value is returned.
Fixes:
|
|
|
Xu Kuohai
|
21c7063f6d |
bpf, lsm: Add disabled BPF LSM hook list
Add a disabled hooks list for BPF LSM. progs being attached to the listed hooks will be rejected by the verifier. Suggested-by: KP Singh <kpsingh@kernel.org> Signed-off-by: Xu Kuohai <xukuohai@huawei.com> Link: https://lore.kernel.org/r/20240719110059.797546-2-xukuohai@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Martin KaFai Lau
|
e42ac14180 |
bpf: Check unsupported ops from the bpf_struct_ops's cfi_stubs
The bpf_tcp_ca struct_ops currently uses a "u32 unsupported_ops[]" array to track which ops is not supported. After cfi_stubs had been added, the function pointer in cfi_stubs is also NULL for the unsupported ops. Thus, the "u32 unsupported_ops[]" becomes redundant. This observation was originally brought up in the bpf/cfi discussion: https://lore.kernel.org/bpf/CAADnVQJoEkdjyCEJRPASjBw1QGsKYrF33QdMGc1RZa9b88bAEA@mail.gmail.com/ The recent bpf qdisc patch (https://lore.kernel.org/bpf/20240714175130.4051012-6-amery.hung@bytedance.com/) also needs to specify quite many unsupported ops. It is a good time to clean it up. This patch removes the need of "u32 unsupported_ops[]" and tests for null-ness in the cfi_stubs instead. Testing the cfi_stubs is done in a new function bpf_struct_ops_supported(). The verifier will call bpf_struct_ops_supported() when loading the struct_ops program. The ".check_member" is removed from the bpf_tcp_ca in this patch. ".check_member" could still be useful for other subsytems to enforce other restrictions (e.g. sched_ext checks for prog->sleepable). To keep the same error return, ENOTSUPP is used. Cc: Amery Hung <ameryhung@gmail.com> Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20240722183049.2254692-2-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> |
|
|
Eduard Zingerman
|
842edb5507 |
bpf: Remove mark_precise_scalar_ids()
Function mark_precise_scalar_ids() is superseded by
bt_sync_linked_regs() and equal scalars tracking in jump history.
mark_precise_scalar_ids() propagates precision over registers sharing
same ID on parent/child state boundaries, while jump history records
allow bt_sync_linked_regs() to propagate same information with
instruction level granularity, which is strictly more precise.
This commit removes mark_precise_scalar_ids() and updates test cases
in progs/verifier_scalar_ids to reflect new verifier behavior.
The tests are updated in the following manner:
- mark_precise_scalar_ids() propagated precision regardless of
presence of conditional jumps, while new jump history based logic
only kicks in when conditional jumps are present.
Hence test cases are augmented with conditional jumps to still
trigger precision propagation.
- As equal scalars tracking no longer relies on parent/child state
boundaries some test cases are no longer interesting,
such test cases are removed, namely:
- precision_same_state and precision_cross_state are superseded by
linked_regs_bpf_k;
- precision_same_state_broken_link and equal_scalars_broken_link
are superseded by linked_regs_broken_link.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240718202357.1746514-3-eddyz87@gmail.com
|
|
|
Eduard Zingerman
|
4bf79f9be4 |
bpf: Track equal scalars history on per-instruction level
Use bpf_verifier_state->jmp_history to track which registers were
updated by find_equal_scalars() (renamed to collect_linked_regs())
when conditional jump was verified. Use recorded information in
backtrack_insn() to propagate precision.
E.g. for the following program:
while verifying instructions
1: r1 = r0 |
2: if r1 < 8 goto ... | push r0,r1 as linked registers in jmp_history
3: if r0 > 16 goto ... | push r0,r1 as linked registers in jmp_history
4: r2 = r10 |
5: r2 += r0 v mark_chain_precision(r0)
while doing mark_chain_precision(r0)
5: r2 += r0 | mark r0 precise
4: r2 = r10 |
3: if r0 > 16 goto ... | mark r0,r1 as precise
2: if r1 < 8 goto ... | mark r0,r1 as precise
1: r1 = r0 v
Technically, do this as follows:
- Use 10 bits to identify each register that gains range because of
sync_linked_regs():
- 3 bits for frame number;
- 6 bits for register or stack slot number;
- 1 bit to indicate if register is spilled.
- Use u64 as a vector of 6 such records + 4 bits for vector length.
- Augment struct bpf_jmp_history_entry with a field 'linked_regs'
representing such vector.
- When doing check_cond_jmp_op() remember up to 6 registers that
gain range because of sync_linked_regs() in such a vector.
- Don't propagate range information and reset IDs for registers that
don't fit in 6-value vector.
- Push a pair {instruction index, linked registers vector}
to bpf_verifier_state->jmp_history.
- When doing backtrack_insn() check if any of recorded linked
registers is currently marked precise, if so mark all linked
registers as precise.
This also requires fixes for two test_verifier tests:
- precise: test 1
- precise: test 2
Both tests contain the following instruction sequence:
19: (bf) r2 = r9 ; R2=scalar(id=3) R9=scalar(id=3)
20: (a5) if r2 < 0x8 goto pc+1 ; R2=scalar(id=3,umin=8)
21: (95) exit
22: (07) r2 += 1 ; R2_w=scalar(id=3+1,...)
23: (bf) r1 = r10 ; R1_w=fp0 R10=fp0
24: (07) r1 += -8 ; R1_w=fp-8
25: (b7) r3 = 0 ; R3_w=0
26: (85) call bpf_probe_read_kernel#113
The call to bpf_probe_read_kernel() at (26) forces r2 to be precise.
Previously, this forced all registers with same id to become precise
immediately when mark_chain_precision() is called.
After this change, the precision is propagated to registers sharing
same id only when 'if' instruction is backtracked.
Hence verification log for both tests is changed:
regs=r2,r9 -> regs=r2 for instructions 25..20.
Fixes:
|
|
Markus Elfring
|
f157f9cb85 |
bpf: Simplify character output in seq_print_delegate_opts()
Single characters should be put into a sequence. Thus use the corresponding function “seq_putc” for two selected calls. This issue was transformed by using the Coccinelle software. Suggested-by: Christophe Jaillet <christophe.jaillet@wanadoo.fr> Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/abde0992-3d71-44d2-ab27-75b382933a22@web.de |
|
|
Markus Elfring
|
df862de41f |
bpf: Replace 8 seq_puts() calls by seq_putc() calls
Single line breaks should occasionally be put into a sequence. Thus use the corresponding function “seq_putc”. This issue was transformed by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/e26b7df9-cd63-491f-85e8-8cabe60a85e5@web.de |
|
Joel Granados
|
78eb4ea25c |
sysctl: treewide: constify the ctl_table argument of proc_handlers
const qualify the struct ctl_table argument in the proc_handler function
signatures. This is a prerequisite to moving the static ctl_table
structs into .rodata data which will ensure that proc_handler function
pointers cannot be modified.
This patch has been generated by the following coccinelle script:
```
virtual patch
@r1@
identifier ctl, write, buffer, lenp, ppos;
identifier func !~ "appldata_(timer|interval)_handler|sched_(rt|rr)_handler|rds_tcp_skbuf_handler|proc_sctp_do_(hmac_alg|rto_min|rto_max|udp_port|alpha_beta|auth|probe_interval)";
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos);
@r2@
identifier func, ctl, write, buffer, lenp, ppos;
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int write, void *buffer, size_t *lenp, loff_t *ppos)
{ ... }
@r3@
identifier func;
@@
int func(
- struct ctl_table *
+ const struct ctl_table *
,int , void *, size_t *, loff_t *);
@r4@
identifier func, ctl;
@@
int func(
- struct ctl_table *ctl
+ const struct ctl_table *ctl
,int , void *, size_t *, loff_t *);
@r5@
identifier func, write, buffer, lenp, ppos;
@@
int func(
- struct ctl_table *
+ const struct ctl_table *
,int write, void *buffer, size_t *lenp, loff_t *ppos);
```
* Code formatting was adjusted in xfs_sysctl.c to comply with code
conventions. The xfs_stats_clear_proc_handler,
xfs_panic_mask_proc_handler and xfs_deprecated_dointvec_minmax where
adjusted.
* The ctl_table argument in proc_watchdog_common was const qualified.
This is called from a proc_handler itself and is calling back into
another proc_handler, making it necessary to change it as part of the
proc_handler migration.
Co-developed-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Co-developed-by: Joel Granados <j.granados@samsung.com>
Signed-off-by: Joel Granados <j.granados@samsung.com>
|
|
Linus Torvalds
|
fbc90c042c |
- 875fa64577da ("mm/hugetlb_vmemmap: fix race with speculative PFN
walkers") is known to cause a performance regression (https://lore.kernel.org/all/3acefad9-96e5-4681-8014-827d6be71c7a@linux.ibm.com/T/#mfa809800a7862fb5bdf834c6f71a3a5113eb83ff). Yu has a fix which I'll send along later via the hotfixes branch. - In the series "mm: Avoid possible overflows in dirty throttling" Jan Kara addresses a couple of issues in the writeback throttling code. These fixes are also targetted at -stable kernels. - Ryusuke Konishi's series "nilfs2: fix potential issues related to reserved inodes" does that. This should actually be in the mm-nonmm-stable tree, along with the many other nilfs2 patches. My bad. - More folio conversions from Kefeng Wang in the series "mm: convert to folio_alloc_mpol()" - Kemeng Shi has sent some cleanups to the writeback code in the series "Add helper functions to remove repeated code and improve readability of cgroup writeback" - Kairui Song has made the swap code a little smaller and a little faster in the series "mm/swap: clean up and optimize swap cache index". - In the series "mm/memory: cleanly support zeropage in vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David Hildenbrand has reworked the rather sketchy handling of the use of the zeropage in MAP_SHARED mappings. I don't see any runtime effects here - more a cleanup/understandability/maintainablity thing. - Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling of higher addresses, for aarch64. The (poorly named) series is "Restructure va_high_addr_switch". - The core TLB handling code gets some cleanups and possible slight optimizations in Bang Li's series "Add update_mmu_tlb_range() to simplify code". - Jane Chu has improved the handling of our fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in the series "Enhance soft hwpoison handling and injection". - Jeff Johnson has sent a billion patches everywhere to add MODULE_DESCRIPTION() to everything. Some landed in this pull. - In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang has simplified migration's use of hardware-offload memory copying. - Yosry Ahmed performs more folio API conversions in his series "mm: zswap: trivial folio conversions". - In the series "large folios swap-in: handle refault cases first", Chuanhua Han inches us forward in the handling of large pages in the swap code. This is a cleanup and optimization, working toward the end objective of full support of large folio swapin/out. - In the series "mm,swap: cleanup VMA based swap readahead window calculation", Huang Ying has contributed some cleanups and a possible fixlet to his VMA based swap readahead code. - In the series "add mTHP support for anonymous shmem" Baolin Wang has taught anonymous shmem mappings to use multisize THP. By default this is a no-op - users must opt in vis sysfs controls. Dramatic improvements in pagefault latency are realized. - David Hildenbrand has some cleanups to our remaining use of page_mapcount() in the series "fs/proc: move page_mapcount() to fs/proc/internal.h". - David also has some highmem accounting cleanups in the series "mm/highmem: don't track highmem pages manually". - Build-time fixes and cleanups from John Hubbard in the series "cleanups, fixes, and progress towards avoiding "make headers"". - Cleanups and consolidation of the core pagemap handling from Barry Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers and utilize them". - Lance Yang's series "Reclaim lazyfree THP without splitting" has reduced the latency of the reclaim of pmd-mapped THPs under fairly common circumstances. A 10x speedup is seen in a microbenchmark. It does this by punting to aother CPU but I guess that's a win unless all CPUs are pegged. - hugetlb_cgroup cleanups from Xiu Jianfeng in the series "mm/hugetlb_cgroup: rework on cftypes". - Miaohe Lin's series "Some cleanups for memory-failure" does just that thing. - Is anyone reading this stuff? If so, email me! - Someone other than SeongJae has developed a DAMON feature in Honggyu Kim's series "DAMON based tiered memory management for CXL memory". This adds DAMON features which may be used to help determine the efficiency of our placement of CXL/PCIe attached DRAM. - DAMON user API centralization and simplificatio work in SeongJae Park's series "mm/damon: introduce DAMON parameters online commit function". - In the series "mm: page_type, zsmalloc and page_mapcount_reset()" David Hildenbrand does some maintenance work on zsmalloc - partially modernizing its use of pageframe fields. - Kefeng Wang provides more folio conversions in the series "mm: remove page_maybe_dma_pinned() and page_mkclean()". - More cleanup from David Hildenbrand, this time in the series "mm/memory_hotplug: use PageOffline() instead of PageReserved() for !ZONE_DEVICE". It "enlightens memory hotplug more about PageOffline() pages" and permits the removal of some virtio-mem hacks. - Barry Song's series "mm: clarify folio_add_new_anon_rmap() and __folio_add_anon_rmap()" is a cleanup to the anon folio handling in preparation for mTHP (multisize THP) swapin. - Kefeng Wang's series "mm: improve clear and copy user folio" implements more folio conversions, this time in the area of large folio userspace copying. - The series "Docs/mm/damon/maintaier-profile: document a mailing tool and community meetup series" tells people how to get better involved with other DAMON developers. From SeongJae Park. - A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does that. - David Hildenbrand sends along more cleanups, this time against the migration code. The series is "mm/migrate: move NUMA hinting fault folio isolation + checks under PTL". - Jan Kara has found quite a lot of strangenesses and minor errors in the readahead code. He addresses this in the series "mm: Fix various readahead quirks". - SeongJae Park's series "selftests/damon: test DAMOS tried regions and {min,max}_nr_regions" adds features and addresses errors in DAMON's self testing code. - Gavin Shan has found a userspace-triggerable WARN in the pagecache code. The series "mm/filemap: Limit page cache size to that supported by xarray" addresses this. The series is marked cc:stable. - Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations and cleanup" cleans up and slightly optimizes KSM. - Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of code motion. The series (which also makes the memcg-v1 code Kconfigurable) are "mm: memcg: separate legacy cgroup v1 code and put under config option" and "mm: memcg: put cgroup v1-specific memcg data under CONFIG_MEMCG_V1" - Dan Schatzberg's series "Add swappiness argument to memory.reclaim" adds an additional feature to this cgroup-v2 control file. - The series "Userspace controls soft-offline pages" from Jiaqi Yan permits userspace to stop the kernel's automatic treatment of excessive correctable memory errors. In order to permit userspace to monitor and handle this situation. - Kefeng Wang's series "mm: migrate: support poison recover from migrate folio" teaches the kernel to appropriately handle migration from poisoned source folios rather than simply panicing. - SeongJae Park's series "Docs/damon: minor fixups and improvements" does those things. - In the series "mm/zsmalloc: change back to per-size_class lock" Chengming Zhou improves zsmalloc's scalability and memory utilization. - Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for pinning memfd folios" makes the GUP code use FOLL_PIN rather than bare refcount increments. So these paes can first be moved aside if they reside in the movable zone or a CMA block. - Andrii Nakryiko has added a binary ioctl()-based API to /proc/pid/maps for much faster reading of vma information. The series is "query VMAs from /proc/<pid>/maps". - In the series "mm: introduce per-order mTHP split counters" Lance Yang improves the kernel's presentation of developer information related to multisize THP splitting. - Michael Ellerman has developed the series "Reimplement huge pages without hugepd on powerpc (8xx, e500, book3s/64)". This permits userspace to use all available huge page sizes. - In the series "revert unconditional slab and page allocator fault injection calls" Vlastimil Babka removes a performance-affecting and not very useful feature from slab fault injection. -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZp2C+QAKCRDdBJ7gKXxA joTkAQDvjqOoFStqk4GU3OXMYB7WCU/ZQMFG0iuu1EEwTVDZ4QEA8CnG7seek1R3 xEoo+vw0sWWeLV3qzsxnCA1BJ8cTJA8= =z0Lf -----END PGP SIGNATURE----- Merge tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - In the series "mm: Avoid possible overflows in dirty throttling" Jan Kara addresses a couple of issues in the writeback throttling code. These fixes are also targetted at -stable kernels. - Ryusuke Konishi's series "nilfs2: fix potential issues related to reserved inodes" does that. This should actually be in the mm-nonmm-stable tree, along with the many other nilfs2 patches. My bad. - More folio conversions from Kefeng Wang in the series "mm: convert to folio_alloc_mpol()" - Kemeng Shi has sent some cleanups to the writeback code in the series "Add helper functions to remove repeated code and improve readability of cgroup writeback" - Kairui Song has made the swap code a little smaller and a little faster in the series "mm/swap: clean up and optimize swap cache index". - In the series "mm/memory: cleanly support zeropage in vm_insert_page*(), vm_map_pages*() and vmf_insert_mixed()" David Hildenbrand has reworked the rather sketchy handling of the use of the zeropage in MAP_SHARED mappings. I don't see any runtime effects here - more a cleanup/understandability/maintainablity thing. - Dev Jain has improved selftests/mm/va_high_addr_switch.c's handling of higher addresses, for aarch64. The (poorly named) series is "Restructure va_high_addr_switch". - The core TLB handling code gets some cleanups and possible slight optimizations in Bang Li's series "Add update_mmu_tlb_range() to simplify code". - Jane Chu has improved the handling of our fake-an-unrecoverable-memory-error testing feature MADV_HWPOISON in the series "Enhance soft hwpoison handling and injection". - Jeff Johnson has sent a billion patches everywhere to add MODULE_DESCRIPTION() to everything. Some landed in this pull. - In the series "mm: cleanup MIGRATE_SYNC_NO_COPY mode", Kefeng Wang has simplified migration's use of hardware-offload memory copying. - Yosry Ahmed performs more folio API conversions in his series "mm: zswap: trivial folio conversions". - In the series "large folios swap-in: handle refault cases first", Chuanhua Han inches us forward in the handling of large pages in the swap code. This is a cleanup and optimization, working toward the end objective of full support of large folio swapin/out. - In the series "mm,swap: cleanup VMA based swap readahead window calculation", Huang Ying has contributed some cleanups and a possible fixlet to his VMA based swap readahead code. - In the series "add mTHP support for anonymous shmem" Baolin Wang has taught anonymous shmem mappings to use multisize THP. By default this is a no-op - users must opt in vis sysfs controls. Dramatic improvements in pagefault latency are realized. - David Hildenbrand has some cleanups to our remaining use of page_mapcount() in the series "fs/proc: move page_mapcount() to fs/proc/internal.h". - David also has some highmem accounting cleanups in the series "mm/highmem: don't track highmem pages manually". - Build-time fixes and cleanups from John Hubbard in the series "cleanups, fixes, and progress towards avoiding "make headers"". - Cleanups and consolidation of the core pagemap handling from Barry Song in the series "mm: introduce pmd|pte_needs_soft_dirty_wp helpers and utilize them". - Lance Yang's series "Reclaim lazyfree THP without splitting" has reduced the latency of the reclaim of pmd-mapped THPs under fairly common circumstances. A 10x speedup is seen in a microbenchmark. It does this by punting to aother CPU but I guess that's a win unless all CPUs are pegged. - hugetlb_cgroup cleanups from Xiu Jianfeng in the series "mm/hugetlb_cgroup: rework on cftypes". - Miaohe Lin's series "Some cleanups for memory-failure" does just that thing. - Someone other than SeongJae has developed a DAMON feature in Honggyu Kim's series "DAMON based tiered memory management for CXL memory". This adds DAMON features which may be used to help determine the efficiency of our placement of CXL/PCIe attached DRAM. - DAMON user API centralization and simplificatio work in SeongJae Park's series "mm/damon: introduce DAMON parameters online commit function". - In the series "mm: page_type, zsmalloc and page_mapcount_reset()" David Hildenbrand does some maintenance work on zsmalloc - partially modernizing its use of pageframe fields. - Kefeng Wang provides more folio conversions in the series "mm: remove page_maybe_dma_pinned() and page_mkclean()". - More cleanup from David Hildenbrand, this time in the series "mm/memory_hotplug: use PageOffline() instead of PageReserved() for !ZONE_DEVICE". It "enlightens memory hotplug more about PageOffline() pages" and permits the removal of some virtio-mem hacks. - Barry Song's series "mm: clarify folio_add_new_anon_rmap() and __folio_add_anon_rmap()" is a cleanup to the anon folio handling in preparation for mTHP (multisize THP) swapin. - Kefeng Wang's series "mm: improve clear and copy user folio" implements more folio conversions, this time in the area of large folio userspace copying. - The series "Docs/mm/damon/maintaier-profile: document a mailing tool and community meetup series" tells people how to get better involved with other DAMON developers. From SeongJae Park. - A large series ("kmsan: Enable on s390") from Ilya Leoshkevich does that. - David Hildenbrand sends along more cleanups, this time against the migration code. The series is "mm/migrate: move NUMA hinting fault folio isolation + checks under PTL". - Jan Kara has found quite a lot of strangenesses and minor errors in the readahead code. He addresses this in the series "mm: Fix various readahead quirks". - SeongJae Park's series "selftests/damon: test DAMOS tried regions and {min,max}_nr_regions" adds features and addresses errors in DAMON's self testing code. - Gavin Shan has found a userspace-triggerable WARN in the pagecache code. The series "mm/filemap: Limit page cache size to that supported by xarray" addresses this. The series is marked cc:stable. - Chengming Zhou's series "mm/ksm: cmp_and_merge_page() optimizations and cleanup" cleans up and slightly optimizes KSM. - Roman Gushchin has separated the memcg-v1 and memcg-v2 code - lots of code motion. The series (which also makes the memcg-v1 code Kconfigurable) are "mm: memcg: separate legacy cgroup v1 code and put under config option" and "mm: memcg: put cgroup v1-specific memcg data under CONFIG_MEMCG_V1" - Dan Schatzberg's series "Add swappiness argument to memory.reclaim" adds an additional feature to this cgroup-v2 control file. - The series "Userspace controls soft-offline pages" from Jiaqi Yan permits userspace to stop the kernel's automatic treatment of excessive correctable memory errors. In order to permit userspace to monitor and handle this situation. - Kefeng Wang's series "mm: migrate: support poison recover from migrate folio" teaches the kernel to appropriately handle migration from poisoned source folios rather than simply panicing. - SeongJae Park's series "Docs/damon: minor fixups and improvements" does those things. - In the series "mm/zsmalloc: change back to per-size_class lock" Chengming Zhou improves zsmalloc's scalability and memory utilization. - Vivek Kasireddy's series "mm/gup: Introduce memfd_pin_folios() for pinning memfd folios" makes the GUP code use FOLL_PIN rather than bare refcount increments. So these paes can first be moved aside if they reside in the movable zone or a CMA block. - Andrii Nakryiko has added a binary ioctl()-based API to /proc/pid/maps for much faster reading of vma information. The series is "query VMAs from /proc/<pid>/maps". - In the series "mm: introduce per-order mTHP split counters" Lance Yang improves the kernel's presentation of developer information related to multisize THP splitting. - Michael Ellerman has developed the series "Reimplement huge pages without hugepd on powerpc (8xx, e500, book3s/64)". This permits userspace to use all available huge page sizes. - In the series "revert unconditional slab and page allocator fault injection calls" Vlastimil Babka removes a performance-affecting and not very useful feature from slab fault injection. * tag 'mm-stable-2024-07-21-14-50' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (411 commits) mm/mglru: fix ineffective protection calculation mm/zswap: fix a white space issue mm/hugetlb: fix kernel NULL pointer dereference when migrating hugetlb folio mm/hugetlb: fix possible recursive locking detected warning mm/gup: clear the LRU flag of a page before adding to LRU batch mm/numa_balancing: teach mpol_to_str about the balancing mode mm: memcg1: convert charge move flags to unsigned long long alloc_tag: fix page_ext_get/page_ext_put sequence during page splitting lib: reuse page_ext_data() to obtain codetag_ref lib: add missing newline character in the warning message mm/mglru: fix overshooting shrinker memory mm/mglru: fix div-by-zero in vmpressure_calc_level() mm/kmemleak: replace strncpy() with strscpy() mm, page_alloc: put should_fail_alloc_page() back behing CONFIG_FAIL_PAGE_ALLOC mm, slab: put should_failslab() back behind CONFIG_SHOULD_FAILSLAB mm: ignore data-race in __swap_writepage hugetlbfs: ensure generic_hugetlb_get_unmapped_area() returns higher address than mmap_min_addr mm: shmem: rename mTHP shmem counters mm: swap_state: use folio_alloc_mpol() in __read_swap_cache_async() mm/migrate: putback split folios when numa hint migration fails ... |
|
Vlastimil Babka
|
53dabce265 |
mm, page_alloc: put should_fail_alloc_page() back behing CONFIG_FAIL_PAGE_ALLOC
This mostly reverts commit
|
|
|
Vlastimil Babka
|
a7526fe8b9 |
mm, slab: put should_failslab() back behind CONFIG_SHOULD_FAILSLAB
Patch series "revert unconditional slab and page allocator fault injection calls". These two patches largely revert commits that added function call overhead into slab and page allocation hotpaths and that cannot be currently disabled even though related CONFIG_ options do exist. A much more involved solution that can keep the callsites always existing but hidden behind a static key if unused, is possible [1] and can be pursued by anyone who believes it's necessary. Meanwhile the fact the should_failslab() error injection is already not functional on kernels built with current gcc without anyone noticing [2], and lukewarm response to [1] suggests the need is not there. I believe it will be more fair to have the state after this series as a baseline for possible further optimisation, instead of the unconditional overhead. For example a possible compromise for anyone who's fine with an empty function call overhead but not the full CONFIG_FAILSLAB / CONFIG_FAIL_PAGE_ALLOC overhead is to reuse patch 1 from [1] but insert a static key check only inside should_failslab() and should_fail_alloc_page() before performing the more expensive checks. [1] https://lore.kernel.org/all/20240620-fault-injection-statickeys-v2-0-e23947d3d84b@suse.cz/#t [2] https://github.com/bpftrace/bpftrace/issues/3258 This patch (of 2): This mostly reverts commit |
|
Jakub Kicinski
|
26f453176a |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZpGVmAAKCRDbK58LschI gxB4AQCgquQis63yqTI36j4iXBT+TuxHEBNoQBSLyzYdrLS1dgD/S5DRJDA+3LD+ 394hn/VtB1qvX5vaqjsov4UIwSMyxA0= =OhSn -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-07-12 We've added 23 non-merge commits during the last 3 day(s) which contain a total of 18 files changed, 234 insertions(+), 243 deletions(-). The main changes are: 1) Improve BPF verifier by utilizing overflow.h helpers to check for overflows, from Shung-Hsi Yu. 2) Fix NULL pointer dereference in resolve_prog_type() for BPF_PROG_TYPE_EXT when attr->attach_prog_fd was not specified, from Tengda Wu. 3) Fix arm64 BPF JIT when generating code for BPF trampolines with BPF_TRAMP_F_CALL_ORIG which corrupted upper address bits, from Puranjay Mohan. 4) Remove test_run callback from lwt_seg6local_prog_ops which never worked in the first place and caused syzbot reports, from Sebastian Andrzej Siewior. 5) Relax BPF verifier to accept non-zero offset on KF_TRUSTED_ARGS/ /KF_RCU-typed BPF kfuncs, from Matt Bobrowski. 6) Fix a long standing bug in libbpf with regards to handling of BPF skeleton's forward and backward compatibility, from Andrii Nakryiko. 7) Annotate btf_{seq,snprintf}_show functions with __printf, from Alan Maguire. 8) BPF selftest improvements to reuse common network helpers in sk_lookup test and dropping the open-coded inetaddr_len() and make_socket() ones, from Geliang Tang. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (23 commits) selftests/bpf: Test for null-pointer-deref bugfix in resolve_prog_type() bpf: Fix null pointer dereference in resolve_prog_type() for BPF_PROG_TYPE_EXT selftests/bpf: DENYLIST.aarch64: Skip fexit_sleep again bpf: use check_sub_overflow() to check for subtraction overflows bpf: use check_add_overflow() to check for addition overflows bpf: fix overflow check in adjust_jmp_off() bpf: Eliminate remaining "make W=1" warnings in kernel/bpf/btf.o bpf: annotate BTF show functions with __printf bpf, arm64: Fix trampoline for BPF_TRAMP_F_CALL_ORIG selftests/bpf: Close obj in error path in xdp_adjust_tail selftests/bpf: Null checks for links in bpf_tcp_ca selftests/bpf: Use connect_fd_to_fd in sk_lookup selftests/bpf: Use start_server_addr in sk_lookup selftests/bpf: Use start_server_str in sk_lookup selftests/bpf: Close fd in error path in drop_on_reuseport selftests/bpf: Add ASSERT_OK_FD macro selftests/bpf: Add backlog for network_helper_opts selftests/bpf: fix compilation failure when CONFIG_NF_FLOW_TABLE=m bpf: Remove tst_run from lwt_seg6local_prog_ops. bpf: relax zero fixed offset constraint on KF_TRUSTED_ARGS/KF_RCU ... ==================== Link: https://patch.msgid.link/20240712212448.5378-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Shung-Hsi Yu
|
deac5871eb |
bpf: use check_sub_overflow() to check for subtraction overflows
Similar to previous patch that drops signed_add*_overflows() and uses
(compiler) builtin-based check_add_overflow(), do the same for
signed_sub*_overflows() and replace them with the generic
check_sub_overflow() to make future refactoring easier and have the
checks implemented more efficiently.
Unsigned overflow check for subtraction does not use helpers and are
simple enough already, so they're left untouched.
After the change GCC 13.3.0 generates cleaner assembly on x86_64:
if (check_sub_overflow(*dst_smin, src_reg->smax_value, dst_smin) ||
139bf: mov 0x28(%r12),%rax
139c4: mov %edx,0x54(%r12)
139c9: sub %r11,%rax
139cc: mov %rax,0x28(%r12)
139d1: jo 14627 <adjust_reg_min_max_vals+0x1237>
check_sub_overflow(*dst_smax, src_reg->smin_value, dst_smax)) {
139d7: mov 0x30(%r12),%rax
139dc: sub %r9,%rax
139df: mov %rax,0x30(%r12)
if (check_sub_overflow(*dst_smin, src_reg->smax_value, dst_smin) ||
139e4: jo 14627 <adjust_reg_min_max_vals+0x1237>
...
*dst_smin = S64_MIN;
14627: movabs $0x8000000000000000,%rax
14631: mov %rax,0x28(%r12)
*dst_smax = S64_MAX;
14636: sub $0x1,%rax
1463a: mov %rax,0x30(%r12)
Before the change it gives:
if (signed_sub_overflows(dst_reg->smin_value, smax_val) ||
13a50: mov 0x28(%r12),%rdi
13a55: mov %edx,0x54(%r12)
dst_reg->smax_value = S64_MAX;
13a5a: movabs $0x7fffffffffffffff,%rdx
13a64: mov %eax,0x50(%r12)
dst_reg->smin_value = S64_MIN;
13a69: movabs $0x8000000000000000,%rax
s64 res = (s64)((u64)a - (u64)b);
13a73: mov %rdi,%rsi
13a76: sub %rcx,%rsi
if (b < 0)
13a79: test %rcx,%rcx
13a7c: js 145ea <adjust_reg_min_max_vals+0x119a>
if (signed_sub_overflows(dst_reg->smin_value, smax_val) ||
13a82: cmp %rsi,%rdi
13a85: jl 13ac7 <adjust_reg_min_max_vals+0x677>
signed_sub_overflows(dst_reg->smax_value, smin_val)) {
13a87: mov 0x30(%r12),%r8
s64 res = (s64)((u64)a - (u64)b);
13a8c: mov %r8,%rax
13a8f: sub %r9,%rax
return res > a;
13a92: cmp %rax,%r8
13a95: setl %sil
if (b < 0)
13a99: test %r9,%r9
13a9c: js 147d1 <adjust_reg_min_max_vals+0x1381>
dst_reg->smax_value = S64_MAX;
13aa2: movabs $0x7fffffffffffffff,%rdx
dst_reg->smin_value = S64_MIN;
13aac: movabs $0x8000000000000000,%rax
if (signed_sub_overflows(dst_reg->smin_value, smax_val) ||
13ab6: test %sil,%sil
13ab9: jne 13ac7 <adjust_reg_min_max_vals+0x677>
dst_reg->smin_value -= smax_val;
13abb: mov %rdi,%rax
dst_reg->smax_value -= smin_val;
13abe: mov %r8,%rdx
dst_reg->smin_value -= smax_val;
13ac1: sub %rcx,%rax
dst_reg->smax_value -= smin_val;
13ac4: sub %r9,%rdx
13ac7: mov %rax,0x28(%r12)
...
13ad1: mov %rdx,0x30(%r12)
...
if (signed_sub_overflows(dst_reg->smin_value, smax_val) ||
145ea: cmp %rsi,%rdi
145ed: jg 13ac7 <adjust_reg_min_max_vals+0x677>
145f3: jmp 13a87 <adjust_reg_min_max_vals+0x637>
Suggested-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20240712080127.136608-4-shung-hsi.yu@suse.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Shung-Hsi Yu
|
28a4411076 |
bpf: use check_add_overflow() to check for addition overflows
signed_add*_overflows() was added back when there was no overflow-check
helper. With the introduction of such helpers in commit
|
|
|
Shung-Hsi Yu
|
4a04b4f0de |
bpf: fix overflow check in adjust_jmp_off()
adjust_jmp_off() incorrectly used the insn->imm field for all overflow check,
which is incorrect as that should only be done or the BPF_JMP32 | BPF_JA case,
not the general jump instruction case. Fix it by using insn->off for overflow
check in the general case.
Fixes:
|
|
Alan Maguire
|
2454075f8e |
bpf: Eliminate remaining "make W=1" warnings in kernel/bpf/btf.o
As reported by Mirsad [1] we still see format warnings in kernel/bpf/btf.o
at W=1 warning level:
CC kernel/bpf/btf.o
./kernel/bpf/btf.c: In function ‘btf_type_seq_show_flags’:
./kernel/bpf/btf.c:7553:21: warning: assignment left-hand side might be a candidate for a format attribute [-Wsuggest-attribute=format]
7553 | sseq.showfn = btf_seq_show;
| ^
./kernel/bpf/btf.c: In function ‘btf_type_snprintf_show’:
./kernel/bpf/btf.c:7604:31: warning: assignment left-hand side might be a candidate for a format attribute [-Wsuggest-attribute=format]
7604 | ssnprintf.show.showfn = btf_snprintf_show;
| ^
Combined with CONFIG_WERROR=y these can halt the build.
The fix (annotating the structure field with __printf())
suggested by Mirsad resolves these. Apologies I missed this last time.
No other W=1 warnings were observed in kernel/bpf after this fix.
[1] https://lore.kernel.org/bpf/92c9d047-f058-400c-9c7d-81d4dc1ef71b@gmail.com/
Fixes:
|
|
|
Alan Maguire
|
b3470da314 |
bpf: annotate BTF show functions with __printf
-Werror=suggest-attribute=format warns about two functions
in kernel/bpf/btf.c [1]; add __printf() annotations to silence
these warnings since for CONFIG_WERROR=y they will trigger
build failures.
[1] https://lore.kernel.org/bpf/a8b20c72-6631-4404-9e1f-0410642d7d20@gmail.com/
Fixes:
|
|
|
Jakub Kicinski
|
7c8267275d |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: net/sched/act_ct.c |
|
Kumar Kartikeya Dwivedi
|
a6fcd19d7e |
bpf: Defer work in bpf_timer_cancel_and_free
Currently, the same case as previous patch (two timer callbacks trying
to cancel each other) can be invoked through bpf_map_update_elem as
well, or more precisely, freeing map elements containing timers. Since
this relies on hrtimer_cancel as well, it is prone to the same deadlock
situation as the previous patch.
It would be sufficient to use hrtimer_try_to_cancel to fix this problem,
as the timer cannot be enqueued after async_cancel_and_free. Once
async_cancel_and_free has been done, the timer must be reinitialized
before it can be armed again. The callback running in parallel trying to
arm the timer will fail, and freeing bpf_hrtimer without waiting is
sufficient (given kfree_rcu), and bpf_timer_cb will return
HRTIMER_NORESTART, preventing the timer from being rearmed again.
However, there exists a UAF scenario where the callback arms the timer
before entering this function, such that if cancellation fails (due to
timer callback invoking this routine, or the target timer callback
running concurrently). In such a case, if the timer expiration is
significantly far in the future, the RCU grace period expiration
happening before it will free the bpf_hrtimer state and along with it
the struct hrtimer, that is enqueued.
Hence, it is clear cancellation needs to occur after
async_cancel_and_free, and yet it cannot be done inline due to deadlock
issues. We thus modify bpf_timer_cancel_and_free to defer work to the
global workqueue, adding a work_struct alongside rcu_head (both used at
_different_ points of time, so can share space).
Update existing code comments to reflect the new state of affairs.
Fixes:
|
|
|
Kumar Kartikeya Dwivedi
|
d4523831f0 |
bpf: Fail bpf_timer_cancel when callback is being cancelled
Given a schedule:
timer1 cb timer2 cb
bpf_timer_cancel(timer2); bpf_timer_cancel(timer1);
Both bpf_timer_cancel calls would wait for the other callback to finish
executing, introducing a lockup.
Add an atomic_t count named 'cancelling' in bpf_hrtimer. This keeps
track of all in-flight cancellation requests for a given BPF timer.
Whenever cancelling a BPF timer, we must check if we have outstanding
cancellation requests, and if so, we must fail the operation with an
error (-EDEADLK) since cancellation is synchronous and waits for the
callback to finish executing. This implies that we can enter a deadlock
situation involving two or more timer callbacks executing in parallel
and attempting to cancel one another.
Note that we avoid incrementing the cancelling counter for the target
timer (the one being cancelled) if bpf_timer_cancel is not invoked from
a callback, to avoid spurious errors. The whole point of detecting
cur->cancelling and returning -EDEADLK is to not enter a busy wait loop
(which may or may not lead to a lockup). This does not apply in case the
caller is in a non-callback context, the other side can continue to
cancel as it sees fit without running into errors.
Background on prior attempts:
Earlier versions of this patch used a bool 'cancelling' bit and used the
following pattern under timer->lock to publish cancellation status.
lock(t->lock);
t->cancelling = true;
mb();
if (cur->cancelling)
return -EDEADLK;
unlock(t->lock);
hrtimer_cancel(t->timer);
t->cancelling = false;
The store outside the critical section could overwrite a parallel
requests t->cancelling assignment to true, to ensure the parallely
executing callback observes its cancellation status.
It would be necessary to clear this cancelling bit once hrtimer_cancel
is done, but lack of serialization introduced races. Another option was
explored where bpf_timer_start would clear the bit when (re)starting the
timer under timer->lock. This would ensure serialized access to the
cancelling bit, but may allow it to be cleared before in-flight
hrtimer_cancel has finished executing, such that lockups can occur
again.
Thus, we choose an atomic counter to keep track of all outstanding
cancellation requests and use it to prevent lockups in case callbacks
attempt to cancel each other while executing in parallel.
Reported-by: Dohyun Kim <dohyunkim@google.com>
Reported-by: Neel Natu <neelnatu@google.com>
Fixes:
|
|
Mohammad Shehar Yaar Tausif
|
af253aef18 |
bpf: fix order of args in call to bpf_map_kvcalloc
The original function call passed size of smap->bucket before the number of buckets which raises the error 'calloc-transposed-args' on compilation. Vlastimil Babka added: The order of parameters can be traced back all the way to |
|
Johannes Weiner
|
3a3b7fec39 |
mm: remove CONFIG_MEMCG_KMEM
CONFIG_MEMCG_KMEM used to be a user-visible option for whether slab tracking is enabled. It has been default-enabled and equivalent to CONFIG_MEMCG for almost a decade. We've only grown more kernel memory accounting sites since, and there is no imaginable cgroup usecase going forward that wants to track user pages but not the multitude of user-drivable kernel allocations. Link: https://lkml.kernel.org/r/20240701153148.452230-1-hannes@cmpxchg.org Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: David Hildenbrand <david@redhat.com> Cc: Muchun Song <muchun.song@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
|
Matt Bobrowski
|
605c96997d |
bpf: relax zero fixed offset constraint on KF_TRUSTED_ARGS/KF_RCU
Currently, BPF kfuncs which accept trusted pointer arguments i.e. those flagged as KF_TRUSTED_ARGS, KF_RCU, or KF_RELEASE, all require an original/unmodified trusted pointer argument to be supplied to them. By original/unmodified, it means that the backing register holding the trusted pointer argument that is to be supplied to the BPF kfunc must have its fixed offset set to zero, or else the BPF verifier will outright reject the BPF program load. However, this zero fixed offset constraint that is currently enforced by the BPF verifier onto BPF kfuncs specifically flagged to accept KF_TRUSTED_ARGS or KF_RCU trusted pointer arguments is rather unnecessary, and can limit their usability in practice. Specifically, it completely eliminates the possibility of constructing a derived trusted pointer from an original trusted pointer. To put it simply, a derived pointer is a pointer which points to one of the nested member fields of the object being pointed to by the original trusted pointer. This patch relaxes the zero fixed offset constraint that is enforced upon BPF kfuncs which specifically accept KF_TRUSTED_ARGS, or KF_RCU arguments. Although, the zero fixed offset constraint technically also applies to BPF kfuncs accepting KF_RELEASE arguments, relaxing this constraint for such BPF kfuncs has subtle and unwanted side-effects. This was discovered by experimenting a little further with an initial version of this patch series [0]. The primary issue with relaxing the zero fixed offset constraint on BPF kfuncs accepting KF_RELEASE arguments is that it'd would open up the opportunity for BPF programs to supply both trusted pointers and derived trusted pointers to them. For KF_RELEASE BPF kfuncs specifically, this could be problematic as resources associated with the backing pointer could be released by the backing BPF kfunc and cause instabilities for the rest of the kernel. With this new fixed offset semantic in-place for BPF kfuncs accepting KF_TRUSTED_ARGS and KF_RCU arguments, we now have more flexibility when it comes to the BPF kfuncs that we're able to introduce moving forward. Early discussions covering the possibility of relaxing the zero fixed offset constraint can be found using the link below. This will provide more context on where all this has stemmed from [1]. Notably, pre-existing tests have been updated such that they provide coverage for the updated zero fixed offset functionality. Specifically, the nested offset test was converted from a negative to positive test as it was already designed to assert zero fixed offset semantics of a KF_TRUSTED_ARGS BPF kfunc. [0] https://lore.kernel.org/bpf/ZnA9ndnXKtHOuYMe@google.com/ [1] https://lore.kernel.org/bpf/ZhkbrM55MKQ0KeIV@google.com/ Signed-off-by: Matt Bobrowski <mattbobrowski@google.com> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20240709210939.1544011-1-mattbobrowski@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Paolo Abeni
|
7b769adc26 |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZoxN0AAKCRDbK58LschI g0c5AQDa3ZV9gfbN42y1zSDoM1uOgO60fb+ydxyOYh8l3+OiQQD/fLfpTY3gBFSY 9yi/pZhw/QdNzQskHNIBrHFGtJbMxgs= =p1Zz -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-07-08 The following pull-request contains BPF updates for your *net-next* tree. We've added 102 non-merge commits during the last 28 day(s) which contain a total of 127 files changed, 4606 insertions(+), 980 deletions(-). The main changes are: 1) Support resilient split BTF which cuts down on duplication and makes BTF as compact as possible wrt BTF from modules, from Alan Maguire & Eduard Zingerman. 2) Add support for dumping kfunc prototypes from BTF which enables both detecting as well as dumping compilable prototypes for kfuncs, from Daniel Xu. 3) Batch of s390x BPF JIT improvements to add support for BPF arena and to implement support for BPF exceptions, from Ilya Leoshkevich. 4) Batch of riscv64 BPF JIT improvements in particular to add 12-argument support for BPF trampolines and to utilize bpf_prog_pack for the latter, from Pu Lehui. 5) Extend BPF test infrastructure to add a CHECKSUM_COMPLETE validation option for skbs and add coverage along with it, from Vadim Fedorenko. 6) Inline bpf_get_current_task/_btf() helpers in the arm64 BPF JIT which gives a small 1% performance improvement in micro-benchmarks, from Puranjay Mohan. 7) Extend the BPF verifier to track the delta between linked registers in order to better deal with recent LLVM code optimizations, from Alexei Starovoitov. 8) Fix bpf_wq_set_callback_impl() kfunc signature where the third argument should have been a pointer to the map value, from Benjamin Tissoires. 9) Extend BPF selftests to add regular expression support for test output matching and adjust some of the selftest when compiled under gcc, from Cupertino Miranda. 10) Simplify task_file_seq_get_next() and remove an unnecessary loop which always iterates exactly once anyway, from Dan Carpenter. 11) Add the capability to offload the netfilter flowtable in XDP layer through kfuncs, from Florian Westphal & Lorenzo Bianconi. 12) Various cleanups in networking helpers in BPF selftests to shave off a few lines of open-coded functions on client/server handling, from Geliang Tang. 13) Properly propagate prog->aux->tail_call_reachable out of BPF verifier, so that x86 JIT does not need to implement detection, from Leon Hwang. 14) Fix BPF verifier to add a missing check_func_arg_reg_off() to prevent an out-of-bounds memory access for dynpointers, from Matt Bobrowski. 15) Fix bpf_session_cookie() kfunc to return __u64 instead of long pointer as it might lead to problems on 32-bit archs, from Jiri Olsa. 16) Enhance traffic validation and dynamic batch size support in xsk selftests, from Tushar Vyavahare. bpf-next-for-netdev * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (102 commits) selftests/bpf: DENYLIST.aarch64: Remove fexit_sleep selftests/bpf: amend for wrong bpf_wq_set_callback_impl signature bpf: helpers: fix bpf_wq_set_callback_impl signature libbpf: Add NULL checks to bpf_object__{prev_map,next_map} selftests/bpf: Remove exceptions tests from DENYLIST.s390x s390/bpf: Implement exceptions s390/bpf: Change seen_reg to a mask bpf: Remove unnecessary loop in task_file_seq_get_next() riscv, bpf: Optimize stack usage of trampoline bpf, devmap: Add .map_alloc_check selftests/bpf: Remove arena tests from DENYLIST.s390x selftests/bpf: Add UAF tests for arena atomics selftests/bpf: Introduce __arena_global s390/bpf: Support arena atomics s390/bpf: Enable arena s390/bpf: Support address space cast instruction s390/bpf: Support BPF_PROBE_MEM32 s390/bpf: Land on the next JITed instruction after exception s390/bpf: Introduce pre- and post- probe functions s390/bpf: Get rid of get_probe_mem_regno() ... ==================== Link: https://patch.msgid.link/20240708221438.10974-1-daniel@iogearbox.net Signed-off-by: Paolo Abeni <pabeni@redhat.com> |
|
Benjamin Tissoires
|
f56f4d541e |
bpf: helpers: fix bpf_wq_set_callback_impl signature
I realized this while having a map containing both a struct bpf_timer and
a struct bpf_wq: the third argument provided to the bpf_wq callback is
not the struct bpf_wq pointer itself, but the pointer to the value in
the map.
Which means that the users need to double cast the provided "value" as
this is not a struct bpf_wq *.
This is a change of API, but there doesn't seem to be much users of bpf_wq
right now, so we should be able to go with this right now.
Fixes:
|
|
Dan Carpenter
|
bc239eb271 |
bpf: Remove unnecessary loop in task_file_seq_get_next()
After commit
|
|
|
Jakub Kicinski
|
76ed626479 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/phy/aquantia/aquantia.h |
|
Florian Lehner
|
fd8db07705 |
bpf, devmap: Add .map_alloc_check
Use the .map_allock_check callback to perform allocation checks before allocating memory for the devmap. Signed-off-by: Florian Lehner <dev@der-flo.net> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20240615101158.57889-1-dev@der-flo.net |
|
Ilya Leoshkevich
|
df34ec9db6 |
bpf: Fix atomic probe zero-extension
Zero-extending results of atomic probe operations fails with:
verifier bug. zext_dst is set, but no reg is defined
The problem is that insn_def_regno() handles BPF_ATOMICs, but not
BPF_PROBE_ATOMICs. Fix by adding the missing condition.
Fixes:
|
|
Sebastian Andrzej Siewior
|
e3d69f585d |
net: Move flush list retrieval to where it is used.
The bpf_net_ctx_get_.*_flush_list() are used at the top of the function. This means the variable is always assigned even if unused. By moving the function to where it is used, it is possible to delay the initialisation until it is unavoidable. Not sure how much this gains in reality but by looking at bq_enqueue() (in devmap.c) gcc pushes one register less to the stack. \o/. Move flush list retrieval to where it is used. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> |
|
|
Sebastian Andrzej Siewior
|
d839a73179 |
net: Optimize xdp_do_flush() with bpf_net_context infos.
Every NIC driver utilizing XDP should invoke xdp_do_flush() after processing all packages. With the introduction of the bpf_net_context logic the flush lists (for dev, CPU-map and xsk) are lazy initialized only if used. However xdp_do_flush() tries to flush all three of them so all three lists are always initialized and the likely empty lists are "iterated". Without the usage of XDP but with CONFIG_DEBUG_NET the lists are also initialized due to xdp_do_check_flushed(). Jakub suggest to utilize the hints in bpf_net_context and avoid invoking the flush function. This will also avoiding initializing the lists which are otherwise unused. Introduce bpf_net_ctx_get_all_used_flush_lists() to return the individual list if not-empty. Use the logic in xdp_do_flush() and xdp_do_check_flushed(). Remove the not needed .*_check_flush(). Suggested-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> |
|
Pu Lehui
|
d1a426171d |
bpf: Use precise image size for struct_ops trampoline
For trampoline using bpf_prog_pack, we need to generate a rw_image buffer with size of (image_end - image). For regular trampoline, we use the precise image size generated by arch_bpf_trampoline_size to allocate rw_image. But for struct_ops trampoline, we allocate rw_image directly using close to PAGE_SIZE size. We do not need to allocate for that much, as the patch size is usually much smaller than PAGE_SIZE. Let's use precise image size for it too. Signed-off-by: Pu Lehui <pulehui@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Tested-by: Björn Töpel <bjorn@rivosinc.com> #riscv Acked-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/bpf/20240622030437.3973492-2-pulehui@huaweicloud.com |
|
|
Jakub Kicinski
|
193b9b2002 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: |
|
|
Linus Torvalds
|
adfbe3640b |
asm-generic fixes for 6.10
These are some bugfixes for system call ABI issues I found while working on a cleanup series. None of these are urgent since these bugs have gone unnoticed for many years, but I think we probably want to backport them all to stable kernels, so it makes sense to have the fixes included as early as possible. One more fix addresses a compile-time warning in kallsyms that was uncovered by a patch I did to enable additional warnings in 6.10. I had mistakenly thought that this fix was already merged through the module tree, but as Geert pointed out it was still missing. -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEiK/NIGsWEZVxh/FrYKtH/8kJUicFAmZ9iRQACgkQYKtH/8kJ UicHIxAA0ej8dMJ3znHovc/CQYkZMpb88bxLlqLotOYuOItEzvR6wd7vnu4cPeZf nHguBiP9RAnzCZhL3F7AS3p8NNJ+P1OZo+sj6tZOANO955mzj1VQ5p2fbSRw+WI3 4Oc1HKvP6UMhHGjU3wHY0+Odd5bpoepN9/fnoiQcHPzq0LbUFM8e4D9KGr51I7fV r7tuDMy9xykEfs6umuDu9wOXih3JkpV9eSmefmjvzgxG3hKLdsvTbWVsVmnKXhZm xdFiTROOmiNvttfkQh0ruBd0drBl8aVhzCKPqIe0vQqS9rBmcf9WTkcJzpihq/fI BA3QjVQFvmHeXs+viaLZf4r/y0qabaTPRBMQxZyEFE0QgtwfxT4/ZnNEbH2s3pIC Pcm0JltLlHLbZs7V63drL6txCoFVndiPXdEBTBsqBwnuDHXCj/tvDcO3tuVTfYoz 9G8TTOsYNEDLYmn8AmzzhJOh75gp6O6A2ui3TtcD9KFNaoTQqqzPJWp8IoxBfxcb 3+rzRWQvXAhfSRBIaejv1quo2ZxoZk3KO3i+ysRITTUF1MLz7b0/Yy/8r74CqmOu 8Iw2Q0BaFPtj1x+VjneQnL++iYWYPEh+ZBEg7AD/z6QHwMLz33SyHlD+/RgRkthV J/L9xUBs5HagWJxRYkVc+l0LOVclTqVJieKD2AWONZ5OFRB+CCI= =ieQy -----END PGP SIGNATURE----- Merge tag 'asm-generic-fixes-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic fixes from Arnd Bergmann: "These are some bugfixes for system call ABI issues I found while working on a cleanup series. None of these are urgent since these bugs have gone unnoticed for many years, but I think we probably want to backport them all to stable kernels, so it makes sense to have the fixes included as early as possible. One more fix addresses a compile-time warning in kallsyms that was uncovered by a patch I did to enable additional warnings in 6.10. I had mistakenly thought that this fix was already merged through the module tree, but as Geert pointed out it was still missing" * tag 'asm-generic-fixes-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: kallsyms: rework symbol lookup return codes linux/syscalls.h: add missing __user annotations syscalls: mmap(): use unsigned offset type consistently s390: remove native mmap2() syscall hexagon: fix fadvise64_64 calling conventions csky, hexagon: fix broken sys_sync_file_range sh: rework sync_file_range ABI powerpc: restore some missing spu syscalls parisc: use generic sys_fanotify_mark implementation parisc: use correct compat recv/recvfrom syscalls sparc: fix compat recv/recvfrom syscalls sparc: fix old compat_sys_select() syscalls: fix compat_sys_io_pgetevents_time64 usage ftruncate: pass a signed offset |
|
Arnd Bergmann
|
7e1f4eb9a6 |
kallsyms: rework symbol lookup return codes
Building with W=1 in some configurations produces a false positive
warning for kallsyms:
kernel/kallsyms.c: In function '__sprint_symbol.isra':
kernel/kallsyms.c:503:17: error: 'strcpy' source argument is the same as destination [-Werror=restrict]
503 | strcpy(buffer, name);
| ^~~~~~~~~~~~~~~~~~~~
This originally showed up while building with -O3, but later started
happening in other configurations as well, depending on inlining
decisions. The underlying issue is that the local 'name' variable is
always initialized to the be the same as 'buffer' in the called functions
that fill the buffer, which gcc notices while inlining, though it could
see that the address check always skips the copy.
The calling conventions here are rather unusual, as all of the internal
lookup functions (bpf_address_lookup, ftrace_mod_address_lookup,
ftrace_func_address_lookup, module_address_lookup and
kallsyms_lookup_buildid) already use the provided buffer and either return
the address of that buffer to indicate success, or NULL for failure,
but the callers are written to also expect an arbitrary other buffer
to be returned.
Rework the calling conventions to return the length of the filled buffer
instead of its address, which is simpler and easier to follow as well
as avoiding the warning. Leave only the kallsyms_lookup() calling conventions
unchanged, since that is called from 16 different functions and
adapting this would be a much bigger change.
Link: https://lore.kernel.org/lkml/20200107214042.855757-1-arnd@arndb.de/
Link: https://lore.kernel.org/lkml/20240326130647.7bfb1d92@gandalf.local.home/
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
|
|
|
Matt Bobrowski
|
ec2b9a5e11 |
bpf: add missing check_func_arg_reg_off() to prevent out-of-bounds memory accesses
Currently, it's possible to pass in a modified CONST_PTR_TO_DYNPTR to a global function as an argument. The adverse effects of this is that BPF helpers can continue to make use of this modified CONST_PTR_TO_DYNPTR from within the context of the global function, which can unintentionally result in out-of-bounds memory accesses and therefore compromise overall system stability i.e. [ 244.157771] BUG: KASAN: slab-out-of-bounds in bpf_dynptr_data+0x137/0x140 [ 244.161345] Read of size 8 at addr ffff88810914be68 by task test_progs/302 [ 244.167151] CPU: 0 PID: 302 Comm: test_progs Tainted: G O E 6.10.0-rc3-00131-g66b586715063 #533 [ 244.174318] Call Trace: [ 244.175787] <TASK> [ 244.177356] dump_stack_lvl+0x66/0xa0 [ 244.179531] print_report+0xce/0x670 [ 244.182314] ? __virt_addr_valid+0x200/0x3e0 [ 244.184908] kasan_report+0xd7/0x110 [ 244.187408] ? bpf_dynptr_data+0x137/0x140 [ 244.189714] ? bpf_dynptr_data+0x137/0x140 [ 244.192020] bpf_dynptr_data+0x137/0x140 [ 244.194264] bpf_prog_b02a02fdd2bdc5fa_global_call_bpf_dynptr_data+0x22/0x26 [ 244.198044] bpf_prog_b0fe7b9d7dc3abde_callback_adjust_bpf_dynptr_reg_off+0x1f/0x23 [ 244.202136] bpf_user_ringbuf_drain+0x2c7/0x570 [ 244.204744] ? 0xffffffffc0009e58 [ 244.206593] ? __pfx_bpf_user_ringbuf_drain+0x10/0x10 [ 244.209795] bpf_prog_33ab33f6a804ba2d_user_ringbuf_callback_const_ptr_to_dynptr_reg_off+0x47/0x4b [ 244.215922] bpf_trampoline_6442502480+0x43/0xe3 [ 244.218691] __x64_sys_prlimit64+0x9/0xf0 [ 244.220912] do_syscall_64+0xc1/0x1d0 [ 244.223043] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 244.226458] RIP: 0033:0x7ffa3eb8f059 [ 244.228582] Code: 08 89 e8 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8f 1d 0d 00 f7 d8 64 89 01 48 [ 244.241307] RSP: 002b:00007ffa3e9c6eb8 EFLAGS: 00000206 ORIG_RAX: 000000000000012e [ 244.246474] RAX: ffffffffffffffda RBX: 00007ffa3e9c7cdc RCX: 00007ffa3eb8f059 [ 244.250478] RDX: 00007ffa3eb162b4 RSI: 0000000000000000 RDI: 00007ffa3e9c7fb0 [ 244.255396] RBP: 00007ffa3e9c6ed0 R08: 00007ffa3e9c76c0 R09: 0000000000000000 [ 244.260195] R10: 0000000000000000 R11: 0000000000000206 R12: ffffffffffffff80 [ 244.264201] R13: 000000000000001c R14: 00007ffc5d6b4260 R15: 00007ffa3e1c7000 [ 244.268303] </TASK> Add a check_func_arg_reg_off() to the path in which the BPF verifier verifies the arguments of global function arguments, specifically those which take an argument of type ARG_PTR_TO_DYNPTR | MEM_RDONLY. Also, process_dynptr_func() doesn't appear to perform any explicit and strict type matching on the supplied register type, so let's also enforce that a register either type PTR_TO_STACK or CONST_PTR_TO_DYNPTR is by the caller. Reported-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Matt Bobrowski <mattbobrowski@google.com> Link: https://lore.kernel.org/r/20240625062857.92760-1-mattbobrowski@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Sebastian Andrzej Siewior
|
3f9fe37d9e |
net: Move per-CPU flush-lists to bpf_net_context on PREEMPT_RT.
The per-CPU flush lists, which are accessed from within the NAPI callback (xdp_do_flush() for instance), are per-CPU. There are subject to the same problem as struct bpf_redirect_info. Add the per-CPU lists cpu_map_flush_list, dev_map_flush_list and xskmap_map_flush_list to struct bpf_net_context. Add wrappers for the access. The lists initialized on first usage (similar to bpf_net_ctx_get_ri()). Cc: "Björn Töpel" <bjorn@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Jonathan Lemon <jonathan.lemon@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Cc: Magnus Karlsson <magnus.karlsson@intel.com> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Song Liu <song@kernel.org> Cc: Stanislav Fomichev <sdf@google.com> Cc: Yonghong Song <yonghong.song@linux.dev> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://patch.msgid.link/20240620132727.660738-16-bigeasy@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Sebastian Andrzej Siewior
|
401cb7dae8 |
net: Reference bpf_redirect_info via task_struct on PREEMPT_RT.
The XDP redirect process is two staged: - bpf_prog_run_xdp() is invoked to run a eBPF program which inspects the packet and makes decisions. While doing that, the per-CPU variable bpf_redirect_info is used. - Afterwards xdp_do_redirect() is invoked and accesses bpf_redirect_info and it may also access other per-CPU variables like xskmap_flush_list. At the very end of the NAPI callback, xdp_do_flush() is invoked which does not access bpf_redirect_info but will touch the individual per-CPU lists. The per-CPU variables are only used in the NAPI callback hence disabling bottom halves is the only protection mechanism. Users from preemptible context (like cpu_map_kthread_run()) explicitly disable bottom halves for protections reasons. Without locking in local_bh_disable() on PREEMPT_RT this data structure requires explicit locking. PREEMPT_RT has forced-threaded interrupts enabled and every NAPI-callback runs in a thread. If each thread has its own data structure then locking can be avoided. Create a struct bpf_net_context which contains struct bpf_redirect_info. Define the variable on stack, use bpf_net_ctx_set() to save a pointer to it, bpf_net_ctx_clear() removes it again. The bpf_net_ctx_set() may nest. For instance a function can be used from within NET_RX_SOFTIRQ/ net_rx_action which uses bpf_net_ctx_set() and NET_TX_SOFTIRQ which does not. Therefore only the first invocations updates the pointer. Use bpf_net_ctx_get_ri() as a wrapper to retrieve the current struct bpf_redirect_info. The returned data structure is zero initialized to ensure nothing is leaked from stack. This is done on first usage of the struct. bpf_net_ctx_set() sets bpf_redirect_info::kern_flags to 0 to note that initialisation is required. First invocation of bpf_net_ctx_get_ri() will memset() the data structure and update bpf_redirect_info::kern_flags. bpf_redirect_info::nh is excluded from memset because it is only used once BPF_F_NEIGH is set which also sets the nh member. The kern_flags is moved past nh to exclude it from memset. The pointer to bpf_net_context is saved task's task_struct. Using always the bpf_net_context approach has the advantage that there is almost zero differences between PREEMPT_RT and non-PREEMPT_RT builds. Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Eduard Zingerman <eddyz87@gmail.com> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Song Liu <song@kernel.org> Cc: Stanislav Fomichev <sdf@google.com> Cc: Yonghong Song <yonghong.song@linux.dev> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Link: https://patch.msgid.link/20240620132727.660738-15-bigeasy@linutronix.de Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Alexei Starovoitov
|
2b2efe1937 |
bpf: Fix may_goto with negative offset.
Zac's syzbot crafted a bpf prog that exposed two bugs in may_goto.
The 1st bug is the way may_goto is patched. When offset is negative
it should be patched differently.
The 2nd bug is in the verifier:
when current state may_goto_depth is equal to visited state may_goto_depth
it means there is an actual infinite loop. It's not correct to prune
exploration of the program at this point.
Note, that this check doesn't limit the program to only one may_goto insn,
since 2nd and any further may_goto will increment may_goto_depth only
in the queued state pushed for future exploration. The current state
will have may_goto_depth == 0 regardless of number of may_goto insns
and the verifier has to explore the program until bpf_exit.
Fixes:
|
|
|
Alan Maguire
|
5a532459aa |
bpf: fix build when CONFIG_DEBUG_INFO_BTF[_MODULES] is undefined
Kernel test robot reports that kernel build fails with resilient split BTF changes. Examining the associated config and code we see that btf_relocate_id() is defined under CONFIG_DEBUG_INFO_BTF_MODULES. Moving it outside the #ifdef solves the issue. Reported-by: kernel test robot <lkp@intel.com> Closes: https://lore.kernel.org/oe-kbuild-all/202406221742.d2srFLVI-lkp@intel.com/ Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Link: https://lore.kernel.org/r/20240623135224.27981-1-alan.maguire@oracle.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Alan Maguire
|
8646db2389 |
libbpf,bpf: Share BTF relocate-related code with kernel
Share relocation implementation with the kernel. As part of this, we also need the type/string iteration functions so also share btf_iter.c file. Relocation code in kernel and userspace is identical save for the impementation of the reparenting of split BTF to the relocated base BTF and retrieval of the BTF header from "struct btf"; these small functions need separate user-space and kernel implementations for the separate "struct btf"s they operate upon. One other wrinkle on the kernel side is we have to map .BTF.ids in modules as they were generated with the type ids used at BTF encoding time. btf_relocate() optionally returns an array mapping from old BTF ids to relocated ids, so we use that to fix up these references where needed for kfuncs. Signed-off-by: Alan Maguire <alan.maguire@oracle.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20240620091733.1967885-5-alan.maguire@oracle.com |
|
Daniel Borkmann
|
cfa1a2329a |
bpf: Fix overrunning reservations in ringbuf
The BPF ring buffer internally is implemented as a power-of-2 sized circular
buffer, with two logical and ever-increasing counters: consumer_pos is the
consumer counter to show which logical position the consumer consumed the
data, and producer_pos which is the producer counter denoting the amount of
data reserved by all producers.
Each time a record is reserved, the producer that "owns" the record will
successfully advance producer counter. In user space each time a record is
read, the consumer of the data advanced the consumer counter once it finished
processing. Both counters are stored in separate pages so that from user
space, the producer counter is read-only and the consumer counter is read-write.
One aspect that simplifies and thus speeds up the implementation of both
producers and consumers is how the data area is mapped twice contiguously
back-to-back in the virtual memory, allowing to not take any special measures
for samples that have to wrap around at the end of the circular buffer data
area, because the next page after the last data page would be first data page
again, and thus the sample will still appear completely contiguous in virtual
memory.
Each record has a struct bpf_ringbuf_hdr { u32 len; u32 pg_off; } header for
book-keeping the length and offset, and is inaccessible to the BPF program.
Helpers like bpf_ringbuf_reserve() return `(void *)hdr + BPF_RINGBUF_HDR_SZ`
for the BPF program to use. Bing-Jhong and Muhammad reported that it is however
possible to make a second allocated memory chunk overlapping with the first
chunk and as a result, the BPF program is now able to edit first chunk's
header.
For example, consider the creation of a BPF_MAP_TYPE_RINGBUF map with size
of 0x4000. Next, the consumer_pos is modified to 0x3000 /before/ a call to
bpf_ringbuf_reserve() is made. This will allocate a chunk A, which is in
[0x0,0x3008], and the BPF program is able to edit [0x8,0x3008]. Now, lets
allocate a chunk B with size 0x3000. This will succeed because consumer_pos
was edited ahead of time to pass the `new_prod_pos - cons_pos > rb->mask`
check. Chunk B will be in range [0x3008,0x6010], and the BPF program is able
to edit [0x3010,0x6010]. Due to the ring buffer memory layout mentioned
earlier, the ranges [0x0,0x4000] and [0x4000,0x8000] point to the same data
pages. This means that chunk B at [0x4000,0x4008] is chunk A's header.
bpf_ringbuf_submit() / bpf_ringbuf_discard() use the header's pg_off to then
locate the bpf_ringbuf itself via bpf_ringbuf_restore_from_rec(). Once chunk
B modified chunk A's header, then bpf_ringbuf_commit() refers to the wrong
page and could cause a crash.
Fix it by calculating the oldest pending_pos and check whether the range
from the oldest outstanding record to the newest would span beyond the ring
buffer size. If that is the case, then reject the request. We've tested with
the ring buffer benchmark in BPF selftests (./benchs/run_bench_ringbufs.sh)
before/after the fix and while it seems a bit slower on some benchmarks, it
is still not significantly enough to matter.
Fixes:
|
|
|
Alexei Starovoitov
|
5337ac4c9b |
bpf: Fix the corner case with may_goto and jump to the 1st insn.
When the following program is processed by the verifier:
L1: may_goto L2
goto L1
L2: w0 = 0
exit
the may_goto insn is first converted to:
L1: r11 = *(u64 *)(r10 -8)
if r11 == 0x0 goto L2
r11 -= 1
*(u64 *)(r10 -8) = r11
goto L1
L2: w0 = 0
exit
then later as the last step the verifier inserts:
*(u64 *)(r10 -8) = BPF_MAX_LOOPS
as the first insn of the program to initialize loop count.
When the first insn happens to be a branch target of some jmp the
bpf_patch_insn_data() logic will produce:
L1: *(u64 *)(r10 -8) = BPF_MAX_LOOPS
r11 = *(u64 *)(r10 -8)
if r11 == 0x0 goto L2
r11 -= 1
*(u64 *)(r10 -8) = r11
goto L1
L2: w0 = 0
exit
because instruction patching adjusts all jmps and calls, but for this
particular corner case it's incorrect and the L1 label should be one
instruction down, like:
*(u64 *)(r10 -8) = BPF_MAX_LOOPS
L1: r11 = *(u64 *)(r10 -8)
if r11 == 0x0 goto L2
r11 -= 1
*(u64 *)(r10 -8) = r11
goto L1
L2: w0 = 0
exit
and that's what this patch is fixing.
After bpf_patch_insn_data() call adjust_jmp_off() to adjust all jmps
that point to newly insert BPF_ST insn to point to insn after.
Note that bpf_patch_insn_data() cannot easily be changed to accommodate
this logic, since jumps that point before or after a sequence of patched
instructions have to be adjusted with the full length of the patch.
Conceptually it's somewhat similar to "insert" of instructions between other
instructions with weird semantics. Like "insert" before 1st insn would require
adjustment of CALL insns to point to newly inserted 1st insn, but not an
adjustment JMP insns that point to 1st, yet still adjusting JMP insns that
cross over 1st insn (point to insn before or insn after), hence use simple
adjust_jmp_off() logic to fix this corner case. Ideally bpf_patch_insn_data()
would have an auxiliary info to say where 'the start of newly inserted patch
is', but it would be too complex for backport.
Fixes:
|
|
|
Matt Bobrowski
|
6ddf3a9abd |
bpf: Add security_file_post_open() LSM hook to sleepable_lsm_hooks
The new generic LSM hook security_file_post_open() was recently added
to the LSM framework in commit
|
|
Rafael Passos
|
21ab4980e0 |
bpf: remove redeclaration of new_n in bpf_verifier_vlog
This new_n is defined in the start of this function. Its value is overwritten by `new_n = min(n, log->len_total);` a couple lines before my change, rendering the shadow declaration unnecessary. Signed-off-by: Rafael Passos <rafael@rcpassos.me> Link: https://lore.kernel.org/r/20240615022641.210320-4-rafael@rcpassos.me Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Rafael Passos
|
ab224b9ef7 |
bpf: remove unused parameter in __bpf_free_used_btfs
Fixes a compiler warning. The __bpf_free_used_btfs function was taking an extra unused struct bpf_prog_aux *aux param Signed-off-by: Rafael Passos <rafael@rcpassos.me> Link: https://lore.kernel.org/r/20240615022641.210320-3-rafael@rcpassos.me Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Rafael Passos
|
9919c5c98c |
bpf: remove unused parameter in bpf_jit_binary_pack_finalize
Fixes a compiler warning. the bpf_jit_binary_pack_finalize function was taking an extra bpf_prog parameter that went unused. This removves it and updates the callers accordingly. Signed-off-by: Rafael Passos <rafael@rcpassos.me> Link: https://lore.kernel.org/r/20240615022641.210320-2-rafael@rcpassos.me Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Leon Hwang
|
01793ed86b |
bpf, verifier: Correct tail_call_reachable for bpf prog
It's confusing to inspect 'prog->aux->tail_call_reachable' with drgn[0], when bpf prog has tail call but 'tail_call_reachable' is false. This patch corrects 'tail_call_reachable' when bpf prog has tail call. Signed-off-by: Leon Hwang <hffilwlqm@gmail.com> Link: https://lore.kernel.org/r/20240610124224.34673-2-hffilwlqm@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jakub Kicinski
|
a6ec08beec |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/ethernet/broadcom/bnxt/bnxt.c |
|
|
Alexei Starovoitov
|
b90d77e5fd |
bpf: Fix remap of arena.
The bpf arena logic didn't account for mremap operation. Add a refcnt for
multiple mmap events to prevent use-after-free in arena_vm_close.
Fixes:
|
|
|
Yonghong Song
|
44b7f7151d |
bpf: Add missed var_off setting in coerce_subreg_to_size_sx()
In coerce_subreg_to_size_sx(), for the case where upper
sign extension bits are the same for smax32 and smin32
values, we missed to setup properly. This is especially
problematic if both smax32 and smin32's sign extension
bits are 1.
The following is a simple example illustrating the inconsistent
verifier states due to missed var_off:
0: (85) call bpf_get_prandom_u32#7 ; R0_w=scalar()
1: (bf) r3 = r0 ; R0_w=scalar(id=1) R3_w=scalar(id=1)
2: (57) r3 &= 15 ; R3_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=15,var_off=(0x0; 0xf))
3: (47) r3 |= 128 ; R3_w=scalar(smin=umin=smin32=umin32=128,smax=umax=smax32=umax32=143,var_off=(0x80; 0xf))
4: (bc) w7 = (s8)w3
REG INVARIANTS VIOLATION (alu): range bounds violation u64=[0xffffff80, 0x8f] s64=[0xffffff80, 0x8f]
u32=[0xffffff80, 0x8f] s32=[0x80, 0xffffff8f] var_off=(0x80, 0xf)
The var_off=(0x80, 0xf) is not correct, and the correct one should
be var_off=(0xffffff80; 0xf) since from insn 3, we know that at
insn 4, the sign extension bits will be 1. This patch fixed this
issue by setting var_off properly.
Fixes:
|
|
|
Yonghong Song
|
380d5f89a4 |
bpf: Add missed var_off setting in set_sext32_default_val()
Zac reported a verification failure and Alexei reproduced the issue
with a simple reproducer ([1]). The verification failure is due to missed
setting for var_off.
The following is the reproducer in [1]:
0: R1=ctx() R10=fp0
0: (71) r3 = *(u8 *)(r10 -387) ;
R3_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=255,var_off=(0x0; 0xff)) R10=fp0
1: (bc) w7 = (s8)w3 ;
R3_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=255,var_off=(0x0; 0xff))
R7_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=127,var_off=(0x0; 0x7f))
2: (36) if w7 >= 0x2533823b goto pc-3
mark_precise: frame0: last_idx 2 first_idx 0 subseq_idx -1
mark_precise: frame0: regs=r7 stack= before 1: (bc) w7 = (s8)w3
mark_precise: frame0: regs=r3 stack= before 0: (71) r3 = *(u8 *)(r10 -387)
2: R7_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=127,var_off=(0x0; 0x7f))
3: (b4) w0 = 0 ; R0_w=0
4: (95) exit
Note that after insn 1, the var_off for R7 is (0x0; 0x7f). This is not correct
since upper 24 bits of w7 could be 0 or 1. So correct var_off should be
(0x0; 0xffffffff). Missing var_off setting in set_sext32_default_val() caused later
incorrect analysis in zext_32_to_64(dst_reg) and reg_bounds_sync(dst_reg).
To fix the issue, set var_off correctly in set_sext32_default_val(). The correct
reg state after insn 1 becomes:
1: (bc) w7 = (s8)w3 ;
R3_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=255,var_off=(0x0; 0xff))
R7_w=scalar(smin=0,smax=umax=0xffffffff,smin32=-128,smax32=127,var_off=(0x0; 0xffffffff))
and at insn 2, the verifier correctly determines either branch is possible.
[1] https://lore.kernel.org/bpf/CAADnVQLPU0Shz7dWV4bn2BgtGdxN3uFHPeobGBA72tpg5Xoykw@mail.gmail.com/
Fixes:
|
|
|
Alexei Starovoitov
|
98d7ca374b |
bpf: Track delta between "linked" registers.
Compilers can generate the code r1 = r2 r1 += 0x1 if r2 < 1000 goto ... use knowledge of r2 range in subsequent r1 operations So remember constant delta between r2 and r1 and update r1 after 'if' condition. Unfortunately LLVM still uses this pattern for loops with 'can_loop' construct: for (i = 0; i < 1000 && can_loop; i++) The "undo" pass was introduced in LLVM https://reviews.llvm.org/D121937 to prevent this optimization, but it cannot cover all cases. Instead of fighting middle end optimizer in BPF backend teach the verifier about this pattern. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20240613013815.953-3-alexei.starovoitov@gmail.com |
|
Vadim Fedorenko
|
65d6d61d25 |
bpf: crypto: make state and IV dynptr nullable
Some ciphers do not require state and IV buffer, but with current implementation 0-sized dynptr is always needed. With adjustment to verifier we can provide NULL instead of 0-sized dynptr. Make crypto kfuncs ready for this. Reviewed-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Vadim Fedorenko <vadfed@meta.com> Link: https://lore.kernel.org/r/20240613211817.1551967-3-vadfed@meta.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Vadim Fedorenko
|
a90797993a |
bpf: verifier: make kfuncs args nullalble
Some arguments to kfuncs might be NULL in some cases. But currently it's not possible to pass NULL to any BTF structures because the check for the suffix is located after all type checks. Move it to earlier place to allow nullable args. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Vadim Fedorenko <vadfed@meta.com> Link: https://lore.kernel.org/r/20240613211817.1551967-2-vadfed@meta.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Maciej Żenczykowski
|
b99a95bc56 |
bpf: fix UML x86_64 compile failure
pcpu_hot (defined in arch/x86) is not available on user mode linux (ARCH=um)
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Fixes:
|
|
Daniel Xu
|
78746f93e9 |
bpf: Fix bpf_dynptr documentation comments
The function argument names were changed but the doc comment was not.
Fix htmldocs build warning by updating doc comments.
Fixes:
|
|
|
Daniel Borkmann
|
e73cd1cfc2 |
bpf: Reduce stack consumption in check_stack_write_fixed_off
The fake_reg moved into env->fake_reg given it consumes a lot of stack space (120 bytes). Migrate the fake_reg in check_stack_write_fixed_off() as well now that we have it. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/r/20240613115310.25383-2-daniel@iogearbox.net Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Daniel Borkmann
|
9242480126 |
bpf: Fix reg_set_min_max corruption of fake_reg
Juan reported that after doing some changes to buzzer [0] and implementing
a new fuzzing strategy guided by coverage, they noticed the following in
one of the probes:
[...]
13: (79) r6 = *(u64 *)(r0 +0) ; R0=map_value(ks=4,vs=8) R6_w=scalar()
14: (b7) r0 = 0 ; R0_w=0
15: (b4) w0 = -1 ; R0_w=0xffffffff
16: (74) w0 >>= 1 ; R0_w=0x7fffffff
17: (5c) w6 &= w0 ; R0_w=0x7fffffff R6_w=scalar(smin=smin32=0,smax=umax=umax32=0x7fffffff,var_off=(0x0; 0x7fffffff))
18: (44) w6 |= 2 ; R6_w=scalar(smin=umin=smin32=umin32=2,smax=umax=umax32=0x7fffffff,var_off=(0x2; 0x7ffffffd))
19: (56) if w6 != 0x7ffffffd goto pc+1
REG INVARIANTS VIOLATION (true_reg2): range bounds violation u64=[0x7fffffff, 0x7ffffffd] s64=[0x7fffffff, 0x7ffffffd] u32=[0x7fffffff, 0x7ffffffd] s32=[0x7fffffff, 0x7ffffffd] var_off=(0x7fffffff, 0x0)
REG INVARIANTS VIOLATION (false_reg1): range bounds violation u64=[0x7fffffff, 0x7ffffffd] s64=[0x7fffffff, 0x7ffffffd] u32=[0x7fffffff, 0x7ffffffd] s32=[0x7fffffff, 0x7ffffffd] var_off=(0x7fffffff, 0x0)
REG INVARIANTS VIOLATION (false_reg2): const tnum out of sync with range bounds u64=[0x0, 0xffffffffffffffff] s64=[0x8000000000000000, 0x7fffffffffffffff] u32=[0x0, 0xffffffff] s32=[0x80000000, 0x7fffffff] var_off=(0x7fffffff, 0x0)
19: R6_w=0x7fffffff
20: (95) exit
from 19 to 21: R0=0x7fffffff R6=scalar(smin=umin=smin32=umin32=2,smax=umax=smax32=umax32=0x7ffffffe,var_off=(0x2; 0x7ffffffd)) R7=map_ptr(ks=4,vs=8) R9=ctx() R10=fp0 fp-24=map_ptr(ks=4,vs=8) fp-40=mmmmmmmm
21: R0=0x7fffffff R6=scalar(smin=umin=smin32=umin32=2,smax=umax=smax32=umax32=0x7ffffffe,var_off=(0x2; 0x7ffffffd)) R7=map_ptr(ks=4,vs=8) R9=ctx() R10=fp0 fp-24=map_ptr(ks=4,vs=8) fp-40=mmmmmmmm
21: (14) w6 -= 2147483632 ; R6_w=scalar(smin=umin=umin32=2,smax=umax=0xffffffff,smin32=0x80000012,smax32=14,var_off=(0x2; 0xfffffffd))
22: (76) if w6 s>= 0xe goto pc+1 ; R6_w=scalar(smin=umin=umin32=2,smax=umax=0xffffffff,smin32=0x80000012,smax32=13,var_off=(0x2; 0xfffffffd))
23: (95) exit
from 22 to 24: R0=0x7fffffff R6_w=14 R7=map_ptr(ks=4,vs=8) R9=ctx() R10=fp0 fp-24=map_ptr(ks=4,vs=8) fp-40=mmmmmmmm
24: R0=0x7fffffff R6_w=14 R7=map_ptr(ks=4,vs=8) R9=ctx() R10=fp0 fp-24=map_ptr(ks=4,vs=8) fp-40=mmmmmmmm
24: (14) w6 -= 14 ; R6_w=0
[...]
What can be seen here is a register invariant violation on line 19. After
the binary-or in line 18, the verifier knows that bit 2 is set but knows
nothing about the rest of the content which was loaded from a map value,
meaning, range is [2,0x7fffffff] with var_off=(0x2; 0x7ffffffd). When in
line 19 the verifier analyzes the branch, it splits the register states
in reg_set_min_max() into the registers of the true branch (true_reg1,
true_reg2) and the registers of the false branch (false_reg1, false_reg2).
Since the test is w6 != 0x7ffffffd, the src_reg is a known constant.
Internally, the verifier creates a "fake" register initialized as scalar
to the value of 0x7ffffffd, and then passes it onto reg_set_min_max(). Now,
for line 19, it is mathematically impossible to take the false branch of
this program, yet the verifier analyzes it. It is impossible because the
second bit of r6 will be set due to the prior or operation and the
constant in the condition has that bit unset (hex(fd) == binary(1111 1101).
When the verifier first analyzes the false / fall-through branch, it will
compute an intersection between the var_off of r6 and of the constant. This
is because the verifier creates a "fake" register initialized to the value
of the constant. The intersection result later refines both registers in
regs_refine_cond_op():
[...]
t = tnum_intersect(tnum_subreg(reg1->var_off), tnum_subreg(reg2->var_off));
reg1->var_off = tnum_with_subreg(reg1->var_off, t);
reg2->var_off = tnum_with_subreg(reg2->var_off, t);
[...]
Since the verifier is analyzing the false branch of the conditional jump,
reg1 is equal to false_reg1 and reg2 is equal to false_reg2, i.e. the reg2
is the "fake" register that was meant to hold a constant value. The resulting
var_off of the intersection says that both registers now hold a known value
of var_off=(0x7fffffff, 0x0) or in other words: this operation manages to
make the verifier think that the "constant" value that was passed in the
jump operation now holds a different value.
Normally this would not be an issue since it should not influence the true
branch, however, false_reg2 and true_reg2 are pointers to the same "fake"
register. Meaning, the false branch can influence the results of the true
branch. In line 24, the verifier assumes R6_w=0, but the actual runtime
value in this case is 1. The fix is simply not passing in the same "fake"
register location as inputs to reg_set_min_max(), but instead making a
copy. Moving the fake_reg into the env also reduces stack consumption by
120 bytes. With this, the verifier successfully rejects invalid accesses
from the test program.
[0] https://github.com/google/buzzer
Fixes:
|
|
|
Daniel Xu
|
cce4c40b96 |
bpf: treewide: Align kfunc signatures to prog point-of-view
Previously, kfunc declarations in bpf_kfuncs.h (and others) used "user
facing" types for kfuncs prototypes while the actual kfunc definitions
used "kernel facing" types. More specifically: bpf_dynptr vs
bpf_dynptr_kern, __sk_buff vs sk_buff, and xdp_md vs xdp_buff.
It wasn't an issue before, as the verifier allows aliased types.
However, since we are now generating kfunc prototypes in vmlinux.h (in
addition to keeping bpf_kfuncs.h around), this conflict creates
compilation errors.
Fix this conflict by using "user facing" types in kfunc definitions.
This results in more casts, but otherwise has no additional runtime
cost.
Note, similar to
|
|
|
Daniel Xu
|
ec209ad863 |
bpf: verifier: Relax caller requirements for kfunc projection type args
Currently, if a kfunc accepts a projection type as an argument (eg struct __sk_buff *), the caller must exactly provide exactly the same type with provable provenance. However in practice, kfuncs that accept projection types _must_ cast to the underlying type before use b/c projection type layouts are completely made up. Thus, it is ok to relax the verifier rules around implicit conversions. We will use this functionality in the next commit when we align kfuncs to user-facing types. Signed-off-by: Daniel Xu <dxu@dxuuu.xyz> Link: https://lore.kernel.org/r/e2c025cb09ccfd4af1ec9e18284dc3cecff7514d.1718207789.git.dxu@dxuuu.xyz Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jakub Kicinski
|
b1156532bc |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZmIsRAAKCRDbK58LschI g4SSAP0bkl6rPMn7zp1h+/l7hlvpp2aVOmasBTe8hIhAGUbluwD/TGq4sNsGgXFI i4tUtFRhw8pOjy2guy6526qyJvBs8wY= =WMhY -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-06-06 We've added 54 non-merge commits during the last 10 day(s) which contain a total of 50 files changed, 1887 insertions(+), 527 deletions(-). The main changes are: 1) Add a user space notification mechanism via epoll when a struct_ops object is getting detached/unregistered, from Kui-Feng Lee. 2) Big batch of BPF selftest refactoring for sockmap and BPF congctl tests, from Geliang Tang. 3) Add BTF field (type and string fields, right now) iterator support to libbpf instead of using existing callback-based approaches, from Andrii Nakryiko. 4) Extend BPF selftests for the latter with a new btf_field_iter selftest, from Alan Maguire. 5) Add new kfuncs for a generic, open-coded bits iterator, from Yafang Shao. 6) Fix BPF selftests' kallsyms_find() helper under kernels configured with CONFIG_LTO_CLANG_THIN, from Yonghong Song. 7) Remove a bunch of unused structs in BPF selftests, from David Alan Gilbert. 8) Convert test_sockmap section names into names understood by libbpf so it can deduce program type and attach type, from Jakub Sitnicki. 9) Extend libbpf with the ability to configure log verbosity via LIBBPF_LOG_LEVEL environment variable, from Mykyta Yatsenko. 10) Fix BPF selftests with regards to bpf_cookie and find_vma flakiness in nested VMs, from Song Liu. 11) Extend riscv32/64 JITs to introduce shift/add helpers to generate Zba optimization, from Xiao Wang. 12) Enable BPF programs to declare arrays and struct fields with kptr, bpf_rb_root, and bpf_list_head, from Kui-Feng Lee. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (54 commits) selftests/bpf: Drop useless arguments of do_test in bpf_tcp_ca selftests/bpf: Use start_test in test_dctcp in bpf_tcp_ca selftests/bpf: Use start_test in test_dctcp_fallback in bpf_tcp_ca selftests/bpf: Add start_test helper in bpf_tcp_ca selftests/bpf: Use connect_to_fd_opts in do_test in bpf_tcp_ca libbpf: Auto-attach struct_ops BPF maps in BPF skeleton selftests/bpf: Add btf_field_iter selftests selftests/bpf: Fix send_signal test with nested CONFIG_PARAVIRT libbpf: Remove callback-based type/string BTF field visitor helpers bpftool: Use BTF field iterator in btfgen libbpf: Make use of BTF field iterator in BTF handling code libbpf: Make use of BTF field iterator in BPF linker code libbpf: Add BTF field iterator selftests/bpf: Ignore .llvm.<hash> suffix in kallsyms_find() selftests/bpf: Fix bpf_cookie and find_vma in nested VM selftests/bpf: Test global bpf_list_head arrays. selftests/bpf: Test global bpf_rb_root arrays and fields in nested struct types. selftests/bpf: Test kptr arrays and kptrs in nested struct fields. bpf: limit the number of levels of a nested struct type. bpf: look into the types of the fields of a struct type recursively. ... ==================== Link: https://lore.kernel.org/r/20240606223146.23020-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Jakub Kicinski
|
62b5bf58b9 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: drivers/net/ethernet/pensando/ionic/ionic_txrx.c |
|
Kui-Feng Lee
|
f19caf57d8 |
bpf: limit the number of levels of a nested struct type.
Limit the number of levels looking into struct types to avoid running out of stack space. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240523174202.461236-7-thinker.li@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Kui-Feng Lee
|
64e8ee8148 |
bpf: look into the types of the fields of a struct type recursively.
The verifier has field information for specific special types, such as
kptr, rbtree root, and list head. These types are handled
differently. However, we did not previously examine the types of fields of
a struct type variable. Field information records were not generated for
the kptrs, rbtree roots, and linked_list heads that are not located at the
outermost struct type of a variable.
For example,
struct A {
struct task_struct __kptr * task;
};
struct B {
struct A mem_a;
}
struct B var_b;
It did not examine "struct A" so as not to generate field information for
the kptr in "struct A" for "var_b".
This patch enables BPF programs to define fields of these special types in
a struct type other than the direct type of a variable or in a struct type
that is the type of a field in the value type of a map.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Link: https://lore.kernel.org/r/20240523174202.461236-6-thinker.li@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Kui-Feng Lee
|
994796c025 |
bpf: create repeated fields for arrays.
The verifier uses field information for certain special types, such as kptr, rbtree root, and list head. These types are treated differently. However, we did not previously support these types in arrays. This update examines arrays and duplicates field information the same number of times as the length of the array if the element type is one of the special types. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240523174202.461236-5-thinker.li@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Kui-Feng Lee
|
a7db0d4f87 |
bpf: refactor btf_find_struct_field() and btf_find_datasec_var().
Move common code of the two functions to btf_find_field_one(). Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240523174202.461236-4-thinker.li@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Kui-Feng Lee
|
482f713379 |
bpf: Remove unnecessary call to btf_field_type_size().
field->size has been initialized by bpf_parse_fields() with the value returned by btf_field_type_size(). Use it instead of calling btf_field_type_size() again. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240523174202.461236-3-thinker.li@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Kui-Feng Lee
|
c95a3be45a |
bpf: Remove unnecessary checks on the offset of btf_field.
reg_find_field_offset() always return a btf_field with a matching offset value. Checking the offset of the returned btf_field is unnecessary. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240523174202.461236-2-thinker.li@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Cong Wang
|
2884dc7d08 |
bpf: Fix a potential use-after-free in bpf_link_free()
After commit |
|
Thorsten Blum
|
2317dc2c22 |
bpf, devmap: Remove unnecessary if check in for loop
The iterator variable dst cannot be NULL and the if check can be removed. Remove it and fix the following Coccinelle/coccicheck warning reported by itnull.cocci: ERROR: iterator variable bound on line 762 cannot be NULL Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20240529101900.103913-2-thorsten.blum@toblux.com |
|
Jiri Olsa
|
aeb8fe0283 |
bpf: Fix bpf_session_cookie BTF_ID in special_kfunc_set list
The bpf_session_cookie is unavailable for !CONFIG_FPROBE as reported
by Sebastian [1].
To fix that we remove CONFIG_FPROBE ifdef for session kfuncs, which
is fine, because there's filter for session programs.
Then based on bpf_trace.o dependency:
obj-$(CONFIG_BPF_EVENTS) += bpf_trace.o
we add bpf_session_cookie BTF_ID in special_kfunc_set list dependency
on CONFIG_BPF_EVENTS.
[1] https://lore.kernel.org/bpf/20240531071557.MvfIqkn7@linutronix.de/T/#m71c6d5ec71db2967288cb79acedc15cc5dbfeec5
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Fixes:
|
|
|
Jakub Kicinski
|
e19de2064f |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/ethernet/ti/icssg/icssg_classifier.c |
|
|
Kui-Feng Lee
|
67c3e8353f |
bpf: export bpf_link_inc_not_zero.
bpf_link_inc_not_zero() will be used by kernel modules. We will use it in bpf_testmod.c later. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240530065946.979330-5-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
1adddc97aa |
bpf: support epoll from bpf struct_ops links.
Add epoll support to bpf struct_ops links to trigger EPOLLHUP event upon detachment. This patch implements the "poll" of the "struct file_operations" for BPF links and introduces a new "poll" operator in the "struct bpf_link_ops". By implementing "poll" of "struct bpf_link_ops" for the links of struct_ops, the file descriptor of a struct_ops link can be added to an epoll file descriptor to receive EPOLLHUP events. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240530065946.979330-4-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
6fb2544ea1 |
bpf: enable detaching links of struct_ops objects.
Implement the detach callback in bpf_link_ops for struct_ops so that user programs can detach a struct_ops link. The subsystems that struct_ops objects are registered to can also use this callback to detach the links being passed to them. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240530065946.979330-3-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
73287fe228 |
bpf: pass bpf_struct_ops_link to callbacks in bpf_struct_ops.
Pass an additional pointer of bpf_struct_ops_link to callback function reg, unreg, and update provided by subsystems defined in bpf_struct_ops. A bpf_struct_ops_map can be registered for multiple links. Passing a pointer of bpf_struct_ops_link helps subsystems to distinguish them. This pointer will be used in the later patches to let the subsystem initiate a detachment on a link that was registered to it previously. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240530065946.979330-2-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
Yafang Shao
|
4665415975 |
bpf: Add bits iterator
Add three new kfuncs for the bits iterator: - bpf_iter_bits_new Initialize a new bits iterator for a given memory area. Due to the limitation of bpf memalloc, the max number of words (8-byte units) that can be iterated over is limited to (4096 / 8). - bpf_iter_bits_next Get the next bit in a bpf_iter_bits - bpf_iter_bits_destroy Destroy a bpf_iter_bits The bits iterator facilitates the iteration of the bits of a memory area, such as cpumask. It can be used in any context and on any address. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240517023034.48138-2-laoar.shao@gmail.com |
|
|
Jakub Kicinski
|
4b3529edbb |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZlWtmQAKCRDbK58LschI g0TUAQDT76jx7Rq1DShCtZ3eqiBMNkYczK8b+GqNsSG8YGduaAEA1jn/GN+H65Rh atQZ/pYAfLZflMV04+XE0GyBr5q1uQg= =NczG -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-05-28 We've added 23 non-merge commits during the last 11 day(s) which contain a total of 45 files changed, 696 insertions(+), 277 deletions(-). The main changes are: 1) Rename skb's mono_delivery_time to tstamp_type for extensibility and add SKB_CLOCK_TAI type support to bpf_skb_set_tstamp(), from Abhishek Chauhan. 2) Add netfilter CT zone ID and direction to bpf_ct_opts so that arbitrary CT zones can be used from XDP/tc BPF netfilter CT helper functions, from Brad Cowie. 3) Several tweaks to the instruction-set.rst IETF doc to address the Last Call review comments, from Dave Thaler. 4) Small batch of riscv64 BPF JIT optimizations in order to emit more compressed instructions to the JITed image for better icache efficiency, from Xiao Wang. 5) Sort bpftool C dump output from BTF, aiming to simplify vmlinux.h diffing and forcing more natural type definitions ordering, from Mykyta Yatsenko. 6) Use DEV_STATS_INC() macro in BPF redirect helpers to silence a syzbot/KCSAN race report for the tx_errors counter, from Jiang Yunshui. 7) Un-constify bpf_func_info in bpftool to fix compilation with LLVM 17+ which started treating const structs as constants and thus breaking full BTF program name resolution, from Ivan Babrou. 8) Fix up BPF program numbers in test_sockmap selftest in order to reduce some of the test-internal array sizes, from Geliang Tang. 9) Small cleanup in Makefile.btf script to use test-ge check for v1.25-only pahole, from Alan Maguire. 10) Fix bpftool's make dependencies for vmlinux.h in order to avoid needless rebuilds in some corner cases, from Artem Savkov. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (23 commits) bpf, net: Use DEV_STAT_INC() bpf, docs: Fix instruction.rst indentation bpf, docs: Clarify call local offset bpf, docs: Add table captions bpf, docs: clarify sign extension of 64-bit use of 32-bit imm bpf, docs: Use RFC 2119 language for ISA requirements bpf, docs: Move sentence about returning R0 to abi.rst bpf: constify member bpf_sysctl_kern:: Table riscv, bpf: Try RVC for reg move within BPF_CMPXCHG JIT riscv, bpf: Use STACK_ALIGN macro for size rounding up riscv, bpf: Optimize zextw insn with Zba extension selftests/bpf: Handle forwarding of UDP CLOCK_TAI packets net: Add additional bit to support clockid_t timestamp type net: Rename mono_delivery_time to tstamp_type for scalabilty selftests/bpf: Update tests for new ct zone opts for nf_conntrack kfuncs net: netfilter: Make ct zone opts configurable for bpf ct helpers selftests/bpf: Fix prog numbers in test_sockmap bpf: Remove unused variable "prev_state" bpftool: Un-const bpf_func_info to fix it for llvm 17 and newer bpf: Fix order of args in call to bpf_map_kvcalloc ... ==================== Link: https://lore.kernel.org/r/20240528105924.30905-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Jakub Kicinski
|
2786ae339e |
bpf-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZlTGFAAKCRDbK58LschI g5NXAP0QRn8nBSxJHIswFSOwRiCyhOhR7YL2P0c+RGcRMA+ZSAD9E1cwsYXsPu3L ummQ52AMaMfouHg6aW+rFIoupkGSnwc= =QctA -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Daniel Borkmann says: ==================== pull-request: bpf 2024-05-27 We've added 15 non-merge commits during the last 7 day(s) which contain a total of 18 files changed, 583 insertions(+), 55 deletions(-). The main changes are: 1) Fix broken BPF multi-uprobe PID filtering logic which filtered by thread while the promise was to filter by process, from Andrii Nakryiko. 2) Fix the recent influx of syzkaller reports to sockmap which triggered a locking rule violation by performing a map_delete, from Jakub Sitnicki. 3) Fixes to netkit driver in particular on skb->pkt_type override upon pass verdict, from Daniel Borkmann. 4) Fix an integer overflow in resolve_btfids which can wrongly trigger build failures, from Friedrich Vock. 5) Follow-up fixes for ARC JIT reported by static analyzers, from Shahab Vahedi. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: selftests/bpf: Cover verifier checks for mutating sockmap/sockhash Revert "bpf, sockmap: Prevent lock inversion deadlock in map delete elem" bpf: Allow delete from sockmap/sockhash only if update is allowed selftests/bpf: Add netkit test for pkt_type selftests/bpf: Add netkit tests for mac address netkit: Fix pkt_type override upon netkit pass verdict netkit: Fix setting mac address in l2 mode ARC, bpf: Fix issues reported by the static analyzers selftests/bpf: extend multi-uprobe tests with USDTs selftests/bpf: extend multi-uprobe tests with child thread case libbpf: detect broken PID filtering logic for multi-uprobe bpf: remove unnecessary rcu_read_{lock,unlock}() in multi-uprobe attach logic bpf: fix multi-uprobe PID filtering logic bpf: Fix potential integer overflow in resolve_btfids MAINTAINERS: Add myself as reviewer of ARM64 BPF JIT ==================== Link: https://lore.kernel.org/r/20240527203551.29712-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
Jakub Sitnicki
|
98e948fb60 |
bpf: Allow delete from sockmap/sockhash only if update is allowed
We have seen an influx of syzkaller reports where a BPF program attached to
a tracepoint triggers a locking rule violation by performing a map_delete
on a sockmap/sockhash.
We don't intend to support this artificial use scenario. Extend the
existing verifier allowed-program-type check for updating sockmap/sockhash
to also cover deleting from a map.
From now on only BPF programs which were previously allowed to update
sockmap/sockhash can delete from these map types.
Fixes:
|
|
|
Linus Torvalds
|
61307b7be4 |
The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs. Notable
series include:
- Lucas Stach has provided some page-mapping
cleanup/consolidation/maintainability work in the series "mm/treewide:
Remove pXd_huge() API".
- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in one
test.
- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being allocated:
number of calls and amount of memory.
- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in largely
similar code sites.
- In his series "mm: page_alloc: freelist migratetype hygiene" Johannes
Weiner has fixed the page allocator's handling of migratetype requests,
with resulting improvements in compaction efficiency.
- In the series "make the hugetlb migration strategy consistent" Baolin
Wang has fixed a hugetlb migration issue, which should improve hugetlb
allocation reliability.
- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when memory
almost met memcg limit".
- In the series "mm/filemap: optimize folio adding and splitting" Kairui
Song has optimized pagecache insertion, yielding ~10% performance
improvement in one test.
- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".
- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".
- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".
- More cleanups from Matthew Wilcox in the series "Various page->flags
cleanups".
- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".
- More folio conversions and cleanups in Matthew Wilcox's series
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"
- David Hildenbrand chipped in with "fs/proc/task_mmu: convert hugetlb
functions to work on folis".
- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".
- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the series
"mm/ksm: fix ksm exec support for prctl".
- Baolin Wang has implemented NUMA balancing for multi-size THPs. This
is a simple first-cut implementation for now. The series is "support
multi-size THP numa balancing".
- Cleanups to vma handling helper functions from Matthew Wilcox in the
series "Unify vma_address and vma_pgoff_address".
- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".
- Improvements to the swapping of multi-size THPs from Ryan Roberts in
the series "Swap-out mTHP without splitting".
- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
- GUP cleanups from David Hildenbrand in "mm/gup: consistently call it
GUP-fast".
- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault path to
use struct vm_fault".
- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".
- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes". Fixes
the initialization code so that migration between different memory types
works as intended.
- David Hildenbrand has improved follow_pte() and fixed an errant driver
in the series "mm: follow_pte() improvements and acrn follow_pte()
fixes".
- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".
- Folio conversions in KSM in Alex Shi's series "transfer page to folio
in KSM".
- Barry Song has added some sysfs stats for monitoring multi-size THP's
in the series "mm: add per-order mTHP alloc and swpout counters".
- Some zswap cleanups from Yosry Ahmed in the series "zswap same-filled
and limit checking cleanups".
- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".
- Multi-size THPs get more work, this time from Lance Yang. His series
"mm/madvise: enhance lazyfreeing with mTHP in madvise_free" optimizes
the freeing of these things.
- Kemeng Shi has added more userspace-visible writeback instrumentation
in the series "Improve visibility of writeback".
- Kemeng Shi then sent some maintenance work on top in the series "Fix
and cleanups to page-writeback".
- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in the
series "Improve anon_vma scalability for anon VMAs". Intel's test bot
reported an improbable 3x improvement in one test.
- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"
- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"
- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as XFAIL".
- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".
- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking".
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCZkgQYwAKCRDdBJ7gKXxA
jrdKAP9WVJdpEcXxpoub/vVE0UWGtffr8foifi9bCwrQrGh5mgEAx7Yf0+d/oBZB
nvA4E0DcPrUAFy144FNM0NTCb7u9vAw=
=V3R/
-----END PGP SIGNATURE-----
Merge tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull mm updates from Andrew Morton:
"The usual shower of singleton fixes and minor series all over MM,
documented (hopefully adequately) in the respective changelogs.
Notable series include:
- Lucas Stach has provided some page-mapping cleanup/consolidation/
maintainability work in the series "mm/treewide: Remove pXd_huge()
API".
- In the series "Allow migrate on protnone reference with
MPOL_PREFERRED_MANY policy", Donet Tom has optimized mempolicy's
MPOL_PREFERRED_MANY mode, yielding almost doubled performance in
one test.
- In their series "Memory allocation profiling" Kent Overstreet and
Suren Baghdasaryan have contributed a means of determining (via
/proc/allocinfo) whereabouts in the kernel memory is being
allocated: number of calls and amount of memory.
- Matthew Wilcox has provided the series "Various significant MM
patches" which does a number of rather unrelated things, but in
largely similar code sites.
- In his series "mm: page_alloc: freelist migratetype hygiene"
Johannes Weiner has fixed the page allocator's handling of
migratetype requests, with resulting improvements in compaction
efficiency.
- In the series "make the hugetlb migration strategy consistent"
Baolin Wang has fixed a hugetlb migration issue, which should
improve hugetlb allocation reliability.
- Liu Shixin has hit an I/O meltdown caused by readahead in a
memory-tight memcg. Addressed in the series "Fix I/O high when
memory almost met memcg limit".
- In the series "mm/filemap: optimize folio adding and splitting"
Kairui Song has optimized pagecache insertion, yielding ~10%
performance improvement in one test.
- Baoquan He has cleaned up and consolidated the early zone
initialization code in the series "mm/mm_init.c: refactor
free_area_init_core()".
- Baoquan has also redone some MM initializatio code in the series
"mm/init: minor clean up and improvement".
- MM helper cleanups from Christoph Hellwig in his series "remove
follow_pfn".
- More cleanups from Matthew Wilcox in the series "Various
page->flags cleanups".
- Vlastimil Babka has contributed maintainability improvements in the
series "memcg_kmem hooks refactoring".
- More folio conversions and cleanups in Matthew Wilcox's series:
"Convert huge_zero_page to huge_zero_folio"
"khugepaged folio conversions"
"Remove page_idle and page_young wrappers"
"Use folio APIs in procfs"
"Clean up __folio_put()"
"Some cleanups for memory-failure"
"Remove page_mapping()"
"More folio compat code removal"
- David Hildenbrand chipped in with "fs/proc/task_mmu: convert
hugetlb functions to work on folis".
- Code consolidation and cleanup work related to GUP's handling of
hugetlbs in Peter Xu's series "mm/gup: Unify hugetlb, part 2".
- Rick Edgecombe has developed some fixes to stack guard gaps in the
series "Cover a guard gap corner case".
- Jinjiang Tu has fixed KSM's behaviour after a fork+exec in the
series "mm/ksm: fix ksm exec support for prctl".
- Baolin Wang has implemented NUMA balancing for multi-size THPs.
This is a simple first-cut implementation for now. The series is
"support multi-size THP numa balancing".
- Cleanups to vma handling helper functions from Matthew Wilcox in
the series "Unify vma_address and vma_pgoff_address".
- Some selftests maintenance work from Dev Jain in the series
"selftests/mm: mremap_test: Optimizations and style fixes".
- Improvements to the swapping of multi-size THPs from Ryan Roberts
in the series "Swap-out mTHP without splitting".
- Kefeng Wang has significantly optimized the handling of arm64's
permission page faults in the series
"arch/mm/fault: accelerate pagefault when badaccess"
"mm: remove arch's private VM_FAULT_BADMAP/BADACCESS"
- GUP cleanups from David Hildenbrand in "mm/gup: consistently call
it GUP-fast".
- hugetlb fault code cleanups from Vishal Moola in "Hugetlb fault
path to use struct vm_fault".
- selftests build fixes from John Hubbard in the series "Fix
selftests/mm build without requiring "make headers"".
- Memory tiering fixes/improvements from Ho-Ren (Jack) Chuang in the
series "Improved Memory Tier Creation for CPUless NUMA Nodes".
Fixes the initialization code so that migration between different
memory types works as intended.
- David Hildenbrand has improved follow_pte() and fixed an errant
driver in the series "mm: follow_pte() improvements and acrn
follow_pte() fixes".
- David also did some cleanup work on large folio mapcounts in his
series "mm: mapcount for large folios + page_mapcount() cleanups".
- Folio conversions in KSM in Alex Shi's series "transfer page to
folio in KSM".
- Barry Song has added some sysfs stats for monitoring multi-size
THP's in the series "mm: add per-order mTHP alloc and swpout
counters".
- Some zswap cleanups from Yosry Ahmed in the series "zswap
same-filled and limit checking cleanups".
- Matthew Wilcox has been looking at buffer_head code and found the
documentation to be lacking. The series is "Improve buffer head
documentation".
- Multi-size THPs get more work, this time from Lance Yang. His
series "mm/madvise: enhance lazyfreeing with mTHP in madvise_free"
optimizes the freeing of these things.
- Kemeng Shi has added more userspace-visible writeback
instrumentation in the series "Improve visibility of writeback".
- Kemeng Shi then sent some maintenance work on top in the series
"Fix and cleanups to page-writeback".
- Matthew Wilcox reduces mmap_lock traffic in the anon vma code in
the series "Improve anon_vma scalability for anon VMAs". Intel's
test bot reported an improbable 3x improvement in one test.
- SeongJae Park adds some DAMON feature work in the series
"mm/damon: add a DAMOS filter type for page granularity access recheck"
"selftests/damon: add DAMOS quota goal test"
- Also some maintenance work in the series
"mm/damon/paddr: simplify page level access re-check for pageout"
"mm/damon: misc fixes and improvements"
- David Hildenbrand has disabled some known-to-fail selftests ni the
series "selftests: mm: cow: flag vmsplice() hugetlb tests as
XFAIL".
- memcg metadata storage optimizations from Shakeel Butt in "memcg:
reduce memory consumption by memcg stats".
- DAX fixes and maintenance work from Vishal Verma in the series
"dax/bus.c: Fixups for dax-bus locking""
* tag 'mm-stable-2024-05-17-19-19' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (426 commits)
memcg, oom: cleanup unused memcg_oom_gfp_mask and memcg_oom_order
selftests/mm: hugetlb_madv_vs_map: avoid test skipping by querying hugepage size at runtime
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_wp
mm/hugetlb: add missing VM_FAULT_SET_HINDEX in hugetlb_fault
selftests: cgroup: add tests to verify the zswap writeback path
mm: memcg: make alloc_mem_cgroup_per_node_info() return bool
mm/damon/core: fix return value from damos_wmark_metric_value
mm: do not update memcg stats for NR_{FILE/SHMEM}_PMDMAPPED
selftests: cgroup: remove redundant enabling of memory controller
Docs/mm/damon/maintainer-profile: allow posting patches based on damon/next tree
Docs/mm/damon/maintainer-profile: change the maintainer's timezone from PST to PT
Docs/mm/damon/design: use a list for supported filters
Docs/admin-guide/mm/damon/usage: fix wrong schemes effective quota update command
Docs/admin-guide/mm/damon/usage: fix wrong example of DAMOS filter matching sysfs file
selftests/damon: classify tests for functionalities and regressions
selftests/damon/_damon_sysfs: use 'is' instead of '==' for 'None'
selftests/damon/_damon_sysfs: find sysfs mount point from /proc/mounts
selftests/damon/_damon_sysfs: check errors from nr_schemes file reads
mm/damon/core: initialize ->esz_bp from damos_quota_init_priv()
selftests/damon: add a test for DAMOS quota goal
...
|
|
|
Mohammad Shehar Yaar Tausif
|
6f130e4d4a |
bpf: Fix order of args in call to bpf_map_kvcalloc
The original function call passed size of smap->bucket before the number of buckets which raises the error 'calloc-transposed-args' on compilation. Signed-off-by: Mohammad Shehar Yaar Tausif <sheharyaar48@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240516072411.42016-1-sheharyaar48@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Linus Torvalds
|
f08a1e912d |
Including fix from Andrii for the issue mentioned in our net-next PR,
the rest is unremarkable.
Current release - regressions:
- virtio_net: fix missed error path rtnl_unlock after control queue
locking rework
Current release - new code bugs:
- bpf: fix KASAN slab-out-of-bounds in percpu_array_map_gen_lookup,
caused by missing nested map handling
- drv: dsa: correct initialization order for KSZ88x3 ports
Previous releases - regressions:
- af_packet: do not call packet_read_pending() from tpacket_destruct_skb()
fix performance regression
- ipv6: fix route deleting failure when metric equals 0, don't assume
0 means not set / default in this case
Previous releases - always broken:
- bridge: couple of syzbot-driven fixes
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=7eys
-----END PGP SIGNATURE-----
Merge tag 'net-6.10-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Current release - regressions:
- virtio_net: fix missed error path rtnl_unlock after control queue
locking rework
Current release - new code bugs:
- bpf: fix KASAN slab-out-of-bounds in percpu_array_map_gen_lookup,
caused by missing nested map handling
- drv: dsa: correct initialization order for KSZ88x3 ports
Previous releases - regressions:
- af_packet: do not call packet_read_pending() from
tpacket_destruct_skb() fix performance regression
- ipv6: fix route deleting failure when metric equals 0, don't assume
0 means not set / default in this case
Previous releases - always broken:
- bridge: couple of syzbot-driven fixes"
* tag 'net-6.10-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (30 commits)
selftests: net: local_termination: annotate the expected failures
net: dsa: microchip: Correct initialization order for KSZ88x3 ports
MAINTAINERS: net: Update reviewers for TI's Ethernet drivers
dt-bindings: net: ti: Update maintainers list
l2tp: fix ICMP error handling for UDP-encap sockets
net: txgbe: fix to control VLAN strip
net: wangxun: match VLAN CTAG and STAG features
net: wangxun: fix to change Rx features
af_packet: do not call packet_read_pending() from tpacket_destruct_skb()
virtio_net: Fix missed rtnl_unlock
netrom: fix possible dead-lock in nr_rt_ioctl()
idpf: don't skip over ethtool tcp-data-split setting
dt-bindings: net: qcom: ethernet: Allow dma-coherent
bonding: fix oops during rmmod
net/ipv6: Fix route deleting failure when metric equals 0
selftests/net: reduce xfrm_policy test time
selftests/bpf: Adjust btf_dump test to reflect recent change in file_operations
selftests/bpf: Adjust test_access_variable_array after a kernel function name change
selftests/net/lib: no need to record ns name if it already exist
net: qrtr: ns: Fix module refcnt
...
|
|
|
Linus Torvalds
|
91b6163be4 |
sysctl changes for v6.10-rc1
Summary
* Removed sentinel elements from ctl_table structs in kernel/*
Removing sentinels in ctl_table arrays reduces the build time size and
runtime memory consumed by ~64 bytes per array. Removals for net/, io_uring/,
mm/, ipc/ and security/ are set to go into mainline through their respective
subsystems making the next release the most likely place where the final
series that removes the check for proc_name == NULL will land. This PR adds
to removals already in arch/, drivers/ and fs/.
* Adjusted ctl_table definitions and references to allow constification
Adjustments:
- Removing unused ctl_table function arguments
- Moving non-const elements from ctl_table to ctl_table_header
- Making ctl_table pointers const in ctl_table_root structure
Making the static ctl_table structs const will increase safety by keeping the
pointers to proc_handler functions in .rodata. Though no ctl_tables where
made const in this PR, the ground work for making that possible has started
with these changes sent by Thomas Weißschuh.
Testing
* These changes went into linux-next after v6.9-rc4; giving it a good month of
testing.
-----BEGIN PGP SIGNATURE-----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=/rQW
-----END PGP SIGNATURE-----
Merge tag 'sysctl-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl
Pull sysctl updates from Joel Granados:
- Remove sentinel elements from ctl_table structs in kernel/*
Removing sentinels in ctl_table arrays reduces the build time size
and runtime memory consumed by ~64 bytes per array. Removals for
net/, io_uring/, mm/, ipc/ and security/ are set to go into mainline
through their respective subsystems making the next release the most
likely place where the final series that removes the check for
proc_name == NULL will land.
This adds to removals already in arch/, drivers/ and fs/.
- Adjust ctl_table definitions and references to allow constification
- Remove unused ctl_table function arguments
- Move non-const elements from ctl_table to ctl_table_header
- Make ctl_table pointers const in ctl_table_root structure
Making the static ctl_table structs const will increase safety by
keeping the pointers to proc_handler functions in .rodata. Though no
ctl_tables where made const in this PR, the ground work for making
that possible has started with these changes sent by Thomas
Weißschuh.
* tag 'sysctl-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/sysctl/sysctl:
sysctl: drop now unnecessary out-of-bounds check
sysctl: move sysctl type to ctl_table_header
sysctl: drop sysctl_is_perm_empty_ctl_table
sysctl: treewide: constify argument ctl_table_root::permissions(table)
sysctl: treewide: drop unused argument ctl_table_root::set_ownership(table)
bpf: Remove the now superfluous sentinel elements from ctl_table array
delayacct: Remove the now superfluous sentinel elements from ctl_table array
kprobes: Remove the now superfluous sentinel elements from ctl_table array
printk: Remove the now superfluous sentinel elements from ctl_table array
scheduler: Remove the now superfluous sentinel elements from ctl_table array
seccomp: Remove the now superfluous sentinel elements from ctl_table array
timekeeping: Remove the now superfluous sentinel elements from ctl_table array
ftrace: Remove the now superfluous sentinel elements from ctl_table array
umh: Remove the now superfluous sentinel elements from ctl_table array
kernel misc: Remove the now superfluous sentinel elements from ctl_table array
|
|
|
Linus Torvalds
|
a49468240e |
Modules changes for v6.10-rc1
Finally something fun. Mike Rapoport does some cleanup to allow us to
take out module_alloc() out of modules into a new paint shedded execmem_alloc()
and execmem_free() so to make emphasis these helpers are actually used outside
of modules. It starts with a no-functional changes API rename / placeholders
to then allow architectures to define their requirements into a new shiny
struct execmem_info with ranges, and requirements for those ranges. Archs
now can intitialize this execmem_info as the last part of mm_core_init() if
they have to diverge from the norm. Each range is a known type clearly
articulated and spelled out in enum execmem_type.
Although a lot of this is major cleanup and prep work for future enhancements an
immediate clear gain is we get to enable KPROBES without MODULES now. That is
ultimately what motiviated to pick this work up again, now with smaller goal as
concrete stepping stone.
This has been sitting on linux-next for a little less than a month, a few issues
were found already and fixed, in particular an odd mips boot issue. Arch folks
reviewed the code too. This is ready for wider exposure and testing.
-----BEGIN PGP SIGNATURE-----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=Nsg4
-----END PGP SIGNATURE-----
Merge tag 'modules-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux
Pull modules updates from Luis Chamberlain:
"Finally something fun. Mike Rapoport does some cleanup to allow us to
take out module_alloc() out of modules into a new paint shedded
execmem_alloc() and execmem_free() so to make emphasis these helpers
are actually used outside of modules.
It starts with a non-functional changes API rename / placeholders to
then allow architectures to define their requirements into a new shiny
struct execmem_info with ranges, and requirements for those ranges.
Archs now can intitialize this execmem_info as the last part of
mm_core_init() if they have to diverge from the norm. Each range is a
known type clearly articulated and spelled out in enum execmem_type.
Although a lot of this is major cleanup and prep work for future
enhancements an immediate clear gain is we get to enable KPROBES
without MODULES now. That is ultimately what motiviated to pick this
work up again, now with smaller goal as concrete stepping stone"
* tag 'modules-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux:
bpf: remove CONFIG_BPF_JIT dependency on CONFIG_MODULES of
kprobes: remove dependency on CONFIG_MODULES
powerpc: use CONFIG_EXECMEM instead of CONFIG_MODULES where appropriate
x86/ftrace: enable dynamic ftrace without CONFIG_MODULES
arch: make execmem setup available regardless of CONFIG_MODULES
powerpc: extend execmem_params for kprobes allocations
arm64: extend execmem_info for generated code allocations
riscv: extend execmem_params for generated code allocations
mm/execmem, arch: convert remaining overrides of module_alloc to execmem
mm/execmem, arch: convert simple overrides of module_alloc to execmem
mm: introduce execmem_alloc() and execmem_free()
module: make module_memory_{alloc,free} more self-contained
sparc: simplify module_alloc()
nios2: define virtual address space for modules
mips: module: rename MODULE_START to MODULES_VADDR
arm64: module: remove unneeded call to kasan_alloc_module_shadow()
kallsyms: replace deprecated strncpy with strscpy
module: allow UNUSED_KSYMS_WHITELIST to be relative against objtree.
|
|
|
Andrii Nakryiko
|
9ee9822908 |
bpf: save extended inner map info for percpu array maps as well
ARRAY_OF_MAPS and HASH_OF_MAPS map types have special logic to save
a few extra fields required for correct operations of ARRAY maps, when
they are used as inner maps. PERCPU_ARRAY maps have similar
requirements as they now support generating inline element lookup
logic. So make sure that both classes of maps are handled correctly.
Reported-by: Jakub Kicinski <kuba@kernel.org>
Fixes:
|
|
|
Linus Torvalds
|
1b294a1f35 |
Networking changes for 6.10.
Core & protocols
----------------
- Complete rework of garbage collection of AF_UNIX sockets.
AF_UNIX is prone to forming reference count cycles due to fd passing
functionality. New method based on Tarjan's Strongly Connected Components
algorithm should be both faster and remove a lot of workarounds
we accumulated over the years.
- Add TCP fraglist GRO support, allowing chaining multiple TCP packets
and forwarding them together. Useful for small switches / routers which
lack basic checksum offload in some scenarios (e.g. PPPoE).
- Support using SMP threads for handling packet backlog i.e. packet
processing from software interfaces and old drivers which don't
use NAPI. This helps move the processing out of the softirq jumble.
- Continue work of converting from rtnl lock to RCU protection.
Don't require rtnl lock when reading: IPv6 routing FIB, IPv6 address
labels, netdev threaded NAPI sysfs files, bonding driver's sysfs files,
MPLS devconf, IPv4 FIB rules, netns IDs, tcp metrics, TC Qdiscs,
neighbor entries, ARP entries via ioctl(SIOCGARP), a lot of the link
information available via rtnetlink.
- Small optimizations from Eric to UDP wake up handling, memory accounting,
RPS/RFS implementation, TCP packet sizing etc.
- Allow direct page recycling in the bulk API used by XDP, for +2% PPS.
- Support peek with an offset on TCP sockets.
- Add MPTCP APIs for querying last time packets were received/sent/acked,
and whether MPTCP "upgrade" succeeded on a TCP socket.
- Add intra-node communication shortcut to improve SMC performance.
- Add IPv6 (and IPv{4,6}-over-IPv{4,6}) support to the GTP protocol driver.
- Add HSR-SAN (RedBOX) mode of operation to the HSR protocol driver.
- Add reset reasons for tracing what caused a TCP reset to be sent.
- Introduce direction attribute for xfrm (IPSec) states.
State can be used either for input or output packet processing.
Things we sprinkled into general kernel code
--------------------------------------------
- Add bitmap_{read,write}(), bitmap_size(), expose BYTES_TO_BITS().
This required touch-ups and renaming of a few existing users.
- Add Endian-dependent __counted_by_{le,be} annotations.
- Make building selftests "quieter" by printing summaries like
"CC object.o" rather than full commands with all the arguments.
Netfilter
---------
- Use GFP_KERNEL to clone elements, to deal better with OOM situations
and avoid failures in the .commit step.
BPF
---
- Add eBPF JIT for ARCv2 CPUs.
- Support attaching kprobe BPF programs through kprobe_multi link in
a session mode, meaning, a BPF program is attached to both function entry
and return, the entry program can decide if the return program gets
executed and the entry program can share u64 cookie value with return
program. "Session mode" is a common use-case for tetragon and bpftrace.
- Add the ability to specify and retrieve BPF cookie for raw tracepoint
programs in order to ease migration from classic to raw tracepoints.
- Add an internal-only BPF per-CPU instruction for resolving per-CPU
memory addresses and implement support in x86, ARM64 and RISC-V JITs.
This allows inlining functions which need to access per-CPU state.
- Optimize x86 BPF JIT's emit_mov_imm64, and add support for various
atomics in bpf_arena which can be JITed as a single x86 instruction.
Support BPF arena on ARM64.
- Add a new bpf_wq API for deferring events and refactor process-context
bpf_timer code to keep common code where possible.
- Harden the BPF verifier's and/or/xor value tracking.
- Introduce crypto kfuncs to let BPF programs call kernel crypto APIs.
- Support bpf_tail_call_static() helper for BPF programs with GCC 13.
- Add bpf_preempt_{disable,enable}() kfuncs in order to allow a BPF
program to have code sections where preemption is disabled.
Driver API
----------
- Skip software TC processing completely if all installed rules are
marked as HW-only, instead of checking the HW-only flag rule by rule.
- Add support for configuring PoE (Power over Ethernet), similar to
the already existing support for PoDL (Power over Data Line) config.
- Initial bits of a queue control API, for now allowing a single queue
to be reset without disturbing packet flow to other queues.
- Common (ethtool) statistics for hardware timestamping.
Tests and tooling
-----------------
- Remove the need to create a config file to run the net forwarding tests
so that a naive "make run_tests" can exercise them.
- Define a method of writing tests which require an external endpoint
to communicate with (to send/receive data towards the test machine).
Add a few such tests.
- Create a shared code library for writing Python tests. Expose the YAML
Netlink library from tools/ to the tests for easy Netlink access.
- Move netfilter tests under net/, extend them, separate performance tests
from correctness tests, and iron out issues found by running them
"on every commit".
- Refactor BPF selftests to use common network helpers.
- Further work filling in YAML definitions of Netlink messages for:
nftables, team driver, bonding interfaces, vlan interfaces, VF info,
TC u32 mark, TC police action.
- Teach Python YAML Netlink to decode attribute policies.
- Extend the definition of the "indexed array" construct in the specs
to cover arrays of scalars rather than just nests.
- Add hyperlinks between definitions in generated Netlink docs.
Drivers
-------
- Make sure unsupported flower control flags are rejected by drivers,
and make more drivers report errors directly to the application rather
than dmesg (large number of driver changes from Asbjørn Sloth Tønnesen).
- Ethernet high-speed NICs:
- Broadcom (bnxt):
- support multiple RSS contexts and steering traffic to them
- support XDP metadata
- make page pool allocations more NUMA aware
- Intel (100G, ice, idpf):
- extract datapath code common among Intel drivers into a library
- use fewer resources in switchdev by sharing queues with the PF
- add PFCP filter support
- add Ethernet filter support
- use a spinlock instead of HW lock in PTP clock ops
- support 5 layer Tx scheduler topology
- nVidia/Mellanox:
- 800G link modes and 100G SerDes speeds
- per-queue IRQ coalescing configuration
- Marvell Octeon:
- support offloading TC packet mark action
- Ethernet NICs consumer, embedded and virtual:
- stop lying about skb->truesize in USB Ethernet drivers, it messes up
TCP memory calculations
- Google cloud vNIC:
- support changing ring size via ethtool
- support ring reset using the queue control API
- VirtIO net:
- expose flow hash from RSS to XDP
- per-queue statistics
- add selftests
- Synopsys (stmmac):
- support controllers which require an RX clock signal from the MII
bus to perform their hardware initialization
- TI:
- icssg_prueth: support ICSSG-based Ethernet on AM65x SR1.0 devices
- icssg_prueth: add SW TX / RX Coalescing based on hrtimers
- cpsw: minimal XDP support
- Renesas (ravb):
- support describing the MDIO bus
- Realtek (r8169):
- add support for RTL8168M
- Microchip Sparx5:
- matchall and flower actions mirred and redirect
- Ethernet switches:
- nVidia/Mellanox:
- improve events processing performance
- Marvell:
- add support for MV88E6250 family internal PHYs
- Microchip:
- add DCB and DSCP mapping support for KSZ switches
- vsc73xx: convert to PHYLINK
- Realtek:
- rtl8226b/rtl8221b: add C45 instances and SerDes switching
- Many driver changes related to PHYLIB and PHYLINK deprecated API cleanup.
- Ethernet PHYs:
- Add a new driver for Airoha EN8811H 2.5 Gigabit PHY.
- micrel: lan8814: add support for PPS out and external timestamp trigger
- WiFi:
- Disable Wireless Extensions (WEXT) in all Wi-Fi 7 devices drivers.
Modern devices can only be configured using nl80211.
- mac80211/cfg80211
- handle color change per link for WiFi 7 Multi-Link Operation
- Intel (iwlwifi):
- don't support puncturing in 5 GHz
- support monitor mode on passive channels
- BZ-W device support
- P2P with HE/EHT support
- re-add support for firmware API 90
- provide channel survey information for Automatic Channel Selection
- MediaTek (mt76):
- mt7921 LED control
- mt7925 EHT radiotap support
- mt7920e PCI support
- Qualcomm (ath11k):
- P2P support for QCA6390, WCN6855 and QCA2066
- support hibernation
- ieee80211-freq-limit Device Tree property support
- Qualcomm (ath12k):
- refactoring in preparation of multi-link support
- suspend and hibernation support
- ACPI support
- debugfs support, including dfs_simulate_radar support
- RealTek:
- rtw88: RTL8723CS SDIO device support
- rtw89: RTL8922AE Wi-Fi 7 PCI device support
- rtw89: complete features of new WiFi 7 chip 8922AE including
BT-coexistence and Wake-on-WLAN
- rtw89: use BIOS ACPI settings to set TX power and channels
- rtl8xxxu: enable Management Frame Protection (MFP) support
- Bluetooth:
- support for Intel BlazarI and Filmore Peak2 (BE201)
- support for MediaTek MT7921S SDIO
- initial support for Intel PCIe BT driver
- remove HCI_AMP support
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=EsC2
-----END PGP SIGNATURE-----
Merge tag 'net-next-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
"Core & protocols:
- Complete rework of garbage collection of AF_UNIX sockets.
AF_UNIX is prone to forming reference count cycles due to fd
passing functionality. New method based on Tarjan's Strongly
Connected Components algorithm should be both faster and remove a
lot of workarounds we accumulated over the years.
- Add TCP fraglist GRO support, allowing chaining multiple TCP
packets and forwarding them together. Useful for small switches /
routers which lack basic checksum offload in some scenarios (e.g.
PPPoE).
- Support using SMP threads for handling packet backlog i.e. packet
processing from software interfaces and old drivers which don't use
NAPI. This helps move the processing out of the softirq jumble.
- Continue work of converting from rtnl lock to RCU protection.
Don't require rtnl lock when reading: IPv6 routing FIB, IPv6
address labels, netdev threaded NAPI sysfs files, bonding driver's
sysfs files, MPLS devconf, IPv4 FIB rules, netns IDs, tcp metrics,
TC Qdiscs, neighbor entries, ARP entries via ioctl(SIOCGARP), a lot
of the link information available via rtnetlink.
- Small optimizations from Eric to UDP wake up handling, memory
accounting, RPS/RFS implementation, TCP packet sizing etc.
- Allow direct page recycling in the bulk API used by XDP, for +2%
PPS.
- Support peek with an offset on TCP sockets.
- Add MPTCP APIs for querying last time packets were received/sent/acked
and whether MPTCP "upgrade" succeeded on a TCP socket.
- Add intra-node communication shortcut to improve SMC performance.
- Add IPv6 (and IPv{4,6}-over-IPv{4,6}) support to the GTP protocol
driver.
- Add HSR-SAN (RedBOX) mode of operation to the HSR protocol driver.
- Add reset reasons for tracing what caused a TCP reset to be sent.
- Introduce direction attribute for xfrm (IPSec) states. State can be
used either for input or output packet processing.
Things we sprinkled into general kernel code:
- Add bitmap_{read,write}(), bitmap_size(), expose BYTES_TO_BITS().
This required touch-ups and renaming of a few existing users.
- Add Endian-dependent __counted_by_{le,be} annotations.
- Make building selftests "quieter" by printing summaries like
"CC object.o" rather than full commands with all the arguments.
Netfilter:
- Use GFP_KERNEL to clone elements, to deal better with OOM
situations and avoid failures in the .commit step.
BPF:
- Add eBPF JIT for ARCv2 CPUs.
- Support attaching kprobe BPF programs through kprobe_multi link in
a session mode, meaning, a BPF program is attached to both function
entry and return, the entry program can decide if the return
program gets executed and the entry program can share u64 cookie
value with return program. "Session mode" is a common use-case for
tetragon and bpftrace.
- Add the ability to specify and retrieve BPF cookie for raw
tracepoint programs in order to ease migration from classic to raw
tracepoints.
- Add an internal-only BPF per-CPU instruction for resolving per-CPU
memory addresses and implement support in x86, ARM64 and RISC-V
JITs. This allows inlining functions which need to access per-CPU
state.
- Optimize x86 BPF JIT's emit_mov_imm64, and add support for various
atomics in bpf_arena which can be JITed as a single x86
instruction. Support BPF arena on ARM64.
- Add a new bpf_wq API for deferring events and refactor
process-context bpf_timer code to keep common code where possible.
- Harden the BPF verifier's and/or/xor value tracking.
- Introduce crypto kfuncs to let BPF programs call kernel crypto
APIs.
- Support bpf_tail_call_static() helper for BPF programs with GCC 13.
- Add bpf_preempt_{disable,enable}() kfuncs in order to allow a BPF
program to have code sections where preemption is disabled.
Driver API:
- Skip software TC processing completely if all installed rules are
marked as HW-only, instead of checking the HW-only flag rule by
rule.
- Add support for configuring PoE (Power over Ethernet), similar to
the already existing support for PoDL (Power over Data Line)
config.
- Initial bits of a queue control API, for now allowing a single
queue to be reset without disturbing packet flow to other queues.
- Common (ethtool) statistics for hardware timestamping.
Tests and tooling:
- Remove the need to create a config file to run the net forwarding
tests so that a naive "make run_tests" can exercise them.
- Define a method of writing tests which require an external endpoint
to communicate with (to send/receive data towards the test
machine). Add a few such tests.
- Create a shared code library for writing Python tests. Expose the
YAML Netlink library from tools/ to the tests for easy Netlink
access.
- Move netfilter tests under net/, extend them, separate performance
tests from correctness tests, and iron out issues found by running
them "on every commit".
- Refactor BPF selftests to use common network helpers.
- Further work filling in YAML definitions of Netlink messages for:
nftables, team driver, bonding interfaces, vlan interfaces, VF
info, TC u32 mark, TC police action.
- Teach Python YAML Netlink to decode attribute policies.
- Extend the definition of the "indexed array" construct in the specs
to cover arrays of scalars rather than just nests.
- Add hyperlinks between definitions in generated Netlink docs.
Drivers:
- Make sure unsupported flower control flags are rejected by drivers,
and make more drivers report errors directly to the application
rather than dmesg (large number of driver changes from Asbjørn
Sloth Tønnesen).
- Ethernet high-speed NICs:
- Broadcom (bnxt):
- support multiple RSS contexts and steering traffic to them
- support XDP metadata
- make page pool allocations more NUMA aware
- Intel (100G, ice, idpf):
- extract datapath code common among Intel drivers into a library
- use fewer resources in switchdev by sharing queues with the PF
- add PFCP filter support
- add Ethernet filter support
- use a spinlock instead of HW lock in PTP clock ops
- support 5 layer Tx scheduler topology
- nVidia/Mellanox:
- 800G link modes and 100G SerDes speeds
- per-queue IRQ coalescing configuration
- Marvell Octeon:
- support offloading TC packet mark action
- Ethernet NICs consumer, embedded and virtual:
- stop lying about skb->truesize in USB Ethernet drivers, it
messes up TCP memory calculations
- Google cloud vNIC:
- support changing ring size via ethtool
- support ring reset using the queue control API
- VirtIO net:
- expose flow hash from RSS to XDP
- per-queue statistics
- add selftests
- Synopsys (stmmac):
- support controllers which require an RX clock signal from the
MII bus to perform their hardware initialization
- TI:
- icssg_prueth: support ICSSG-based Ethernet on AM65x SR1.0 devices
- icssg_prueth: add SW TX / RX Coalescing based on hrtimers
- cpsw: minimal XDP support
- Renesas (ravb):
- support describing the MDIO bus
- Realtek (r8169):
- add support for RTL8168M
- Microchip Sparx5:
- matchall and flower actions mirred and redirect
- Ethernet switches:
- nVidia/Mellanox:
- improve events processing performance
- Marvell:
- add support for MV88E6250 family internal PHYs
- Microchip:
- add DCB and DSCP mapping support for KSZ switches
- vsc73xx: convert to PHYLINK
- Realtek:
- rtl8226b/rtl8221b: add C45 instances and SerDes switching
- Many driver changes related to PHYLIB and PHYLINK deprecated API
cleanup
- Ethernet PHYs:
- Add a new driver for Airoha EN8811H 2.5 Gigabit PHY.
- micrel: lan8814: add support for PPS out and external timestamp trigger
- WiFi:
- Disable Wireless Extensions (WEXT) in all Wi-Fi 7 devices
drivers. Modern devices can only be configured using nl80211.
- mac80211/cfg80211
- handle color change per link for WiFi 7 Multi-Link Operation
- Intel (iwlwifi):
- don't support puncturing in 5 GHz
- support monitor mode on passive channels
- BZ-W device support
- P2P with HE/EHT support
- re-add support for firmware API 90
- provide channel survey information for Automatic Channel Selection
- MediaTek (mt76):
- mt7921 LED control
- mt7925 EHT radiotap support
- mt7920e PCI support
- Qualcomm (ath11k):
- P2P support for QCA6390, WCN6855 and QCA2066
- support hibernation
- ieee80211-freq-limit Device Tree property support
- Qualcomm (ath12k):
- refactoring in preparation of multi-link support
- suspend and hibernation support
- ACPI support
- debugfs support, including dfs_simulate_radar support
- RealTek:
- rtw88: RTL8723CS SDIO device support
- rtw89: RTL8922AE Wi-Fi 7 PCI device support
- rtw89: complete features of new WiFi 7 chip 8922AE including
BT-coexistence and Wake-on-WLAN
- rtw89: use BIOS ACPI settings to set TX power and channels
- rtl8xxxu: enable Management Frame Protection (MFP) support
- Bluetooth:
- support for Intel BlazarI and Filmore Peak2 (BE201)
- support for MediaTek MT7921S SDIO
- initial support for Intel PCIe BT driver
- remove HCI_AMP support"
* tag 'net-next-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1827 commits)
selftests: netfilter: fix packetdrill conntrack testcase
net: gro: fix napi_gro_cb zeroed alignment
Bluetooth: btintel_pcie: Refactor and code cleanup
Bluetooth: btintel_pcie: Fix warning reported by sparse
Bluetooth: hci_core: Fix not handling hdev->le_num_of_adv_sets=1
Bluetooth: btintel: Fix compiler warning for multi_v7_defconfig config
Bluetooth: btintel_pcie: Fix compiler warnings
Bluetooth: btintel_pcie: Add *setup* function to download firmware
Bluetooth: btintel_pcie: Add support for PCIe transport
Bluetooth: btintel: Export few static functions
Bluetooth: HCI: Remove HCI_AMP support
Bluetooth: L2CAP: Fix div-by-zero in l2cap_le_flowctl_init()
Bluetooth: qca: Fix error code in qca_read_fw_build_info()
Bluetooth: hci_conn: Use __counted_by() and avoid -Wfamnae warning
Bluetooth: btintel: Add support for Filmore Peak2 (BE201)
Bluetooth: btintel: Add support for BlazarI
LE Create Connection command timeout increased to 20 secs
dt-bindings: net: bluetooth: Add MediaTek MT7921S SDIO Bluetooth
Bluetooth: compute LE flow credits based on recvbuf space
Bluetooth: hci_sync: Use cmd->num_cis instead of magic number
...
|
|
|
Jakub Kicinski
|
654de42f3f |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in late fixes to prepare for the 6.10 net-next PR. Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
Mike Rapoport (IBM)
|
2c9e5d4a00 |
bpf: remove CONFIG_BPF_JIT dependency on CONFIG_MODULES of
BPF just-in-time compiler depended on CONFIG_MODULES because it used module_alloc() to allocate memory for the generated code. Since code allocations are now implemented with execmem, drop dependency of CONFIG_BPF_JIT on CONFIG_MODULES and make it select CONFIG_EXECMEM. Suggested-by: Björn Töpel <bjorn@kernel.org> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> |
|
|
Mike Rapoport (IBM)
|
12af2b83d0 |
mm: introduce execmem_alloc() and execmem_free()
module_alloc() is used everywhere as a mean to allocate memory for code. Beside being semantically wrong, this unnecessarily ties all subsystems that need to allocate code, such as ftrace, kprobes and BPF to modules and puts the burden of code allocation to the modules code. Several architectures override module_alloc() because of various constraints where the executable memory can be located and this causes additional obstacles for improvements of code allocation. Start splitting code allocation from modules by introducing execmem_alloc() and execmem_free() APIs. Initially, execmem_alloc() is a wrapper for module_alloc() and execmem_free() is a replacement of module_memfree() to allow updating all call sites to use the new APIs. Since architectures define different restrictions on placement, permissions, alignment and other parameters for memory that can be used by different subsystems that allocate executable memory, execmem_alloc() takes a type argument, that will be used to identify the calling subsystem and to allow architectures define parameters for ranges suitable for that subsystem. No functional changes. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Song Liu <song@kernel.org> Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> |
|
|
Jakub Kicinski
|
6e62702feb |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZkGcZAAKCRDbK58LschI g6o6APwLsqhrM2w71VUN5ciCxu4H5VDtZp6wkdqtVbxxU4qNxQEApKgYgKt8ZLF3 Kily5c7m+S4ZXhMX21rb8JhSAz0dfQk= =5Dk7 -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-05-13 We've added 119 non-merge commits during the last 14 day(s) which contain a total of 134 files changed, 9462 insertions(+), 4742 deletions(-). The main changes are: 1) Add BPF JIT support for 32-bit ARCv2 processors, from Shahab Vahedi. 2) Add BPF range computation improvements to the verifier in particular around XOR and OR operators, refactoring of checks for range computation and relaxing MUL range computation so that src_reg can also be an unknown scalar, from Cupertino Miranda. 3) Add support to attach kprobe BPF programs through kprobe_multi link in a session mode, meaning, a BPF program is attached to both function entry and return, the entry program can decide if the return program gets executed and the entry program can share u64 cookie value with return program. Session mode is a common use-case for tetragon and bpftrace, from Jiri Olsa. 4) Fix a potential overflow in libbpf's ring__consume_n() and improve libbpf as well as BPF selftest's struct_ops handling, from Andrii Nakryiko. 5) Improvements to BPF selftests in context of BPF gcc backend, from Jose E. Marchesi & David Faust. 6) Migrate remaining BPF selftest tests from test_sock_addr.c to prog_test- -style in order to retire the old test, run it in BPF CI and additionally expand test coverage, from Jordan Rife. 7) Big batch for BPF selftest refactoring in order to remove duplicate code around common network helpers, from Geliang Tang. 8) Another batch of improvements to BPF selftests to retire obsolete bpf_tcp_helpers.h as everything is available vmlinux.h, from Martin KaFai Lau. 9) Fix BPF map tear-down to not walk the map twice on free when both timer and wq is used, from Benjamin Tissoires. 10) Fix BPF verifier assumptions about socket->sk that it can be non-NULL, from Alexei Starovoitov. 11) Change BTF build scripts to using --btf_features for pahole v1.26+, from Alan Maguire. 12) Small improvements to BPF reusing struct_size() and krealloc_array(), from Andy Shevchenko. 13) Fix s390 JIT to emit a barrier for BPF_FETCH instructions, from Ilya Leoshkevich. 14) Extend TCP ->cong_control() callback in order to feed in ack and flag parameters and allow write-access to tp->snd_cwnd_stamp from BPF program, from Miao Xu. 15) Add support for internal-only per-CPU instructions to inline bpf_get_smp_processor_id() helper call for arm64 and riscv64 BPF JITs, from Puranjay Mohan. 16) Follow-up to remove the redundant ethtool.h from tooling infrastructure, from Tushar Vyavahare. 17) Extend libbpf to support "module:<function>" syntax for tracing programs, from Viktor Malik. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (119 commits) bpf: make list_for_each_entry portable bpf: ignore expected GCC warning in test_global_func10.c bpf: disable strict aliasing in test_global_func9.c selftests/bpf: Free strdup memory in xdp_hw_metadata selftests/bpf: Fix a few tests for GCC related warnings. bpf: avoid gcc overflow warning in test_xdp_vlan.c tools: remove redundant ethtool.h from tooling infra selftests/bpf: Expand ATTACH_REJECT tests selftests/bpf: Expand getsockname and getpeername tests sefltests/bpf: Expand sockaddr hook deny tests selftests/bpf: Expand sockaddr program return value tests selftests/bpf: Retire test_sock_addr.(c|sh) selftests/bpf: Remove redundant sendmsg test cases selftests/bpf: Migrate ATTACH_REJECT test cases selftests/bpf: Migrate expected_attach_type tests selftests/bpf: Migrate wildcard destination rewrite test selftests/bpf: Migrate sendmsg6 v4 mapped address tests selftests/bpf: Migrate sendmsg deny test cases selftests/bpf: Migrate WILDCARD_IP test selftests/bpf: Handle SYSCALL_EPERM and SYSCALL_ENOTSUPP test cases ... ==================== Link: https://lore.kernel.org/r/20240513134114.17575-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Linus Torvalds
|
c0b9620bc3 |
RCU pull request for v6.10
This pull request contains the following branches: fixes.2024.04.15a: Fix a lockdep complain for lazy-preemptible kernel, remove redundant BH disable for TINY_RCU, remove redundant READ_ONCE() in tree.c, fix false positives KCSAN splat and fix buffer overflow in the print_cpu_stall_info(). misc.2024.04.12a: Misc updates related to bpf, tracing and update the MAINTAINERS file. rcu-sync-normal-improve.2024.04.15a: An improvement of a normal synchronize_rcu() call in terms of latency. It maintains a separate track for sync. users only. This approach bypasses per-cpu nocb-lists thus sync-users do not depend on nocb-list length and how fast regular callbacks are processed. rcu-tasks.2024.04.15a: RCU tasks, switch tasks RCU grace periods to sleep at TASK_IDLE priority, fix some comments, add some diagnostic warning to the exit_tasks_rcu_start() and fix a buffer overflow in the show_rcu_tasks_trace_gp_kthread(). rcutorture.2024.04.15a: Increase memory to guest OS, fix a Tasks Rude RCU testing, some updates for TREE09, dump mode information to debug GP kthread state, remove redundant READ_ONCE(), fix some comments about RCU_TORTURE_PIPE_LEN and pipe_count, remove some redundant pointer initialization, fix a hung splat task by when the rcutorture tests start to exit, fix invalid context warning, add '--do-kvfree' parameter to torture test and use slow register unregister callbacks only for rcutype test. -----BEGIN PGP SIGNATURE----- iQGzBAABCgAdFiEEu6QRe/mAUYNn5U0PBYqkjnKWLM8FAmYzsmUACgkQBYqkjnKW LM/FAwv+LcIJ9lO/wzUpnH3d3djBOPmyu7Us8ERNY5lcVZ+neS2m3vxq0kOk/cnV RGgZc7qjWqMQ9hAx/MmIodmiw036ceRDe5CP/Ec/TYx68m+NPG3VnP08s/xLXLlx n8aSJJu37y0ElMQMwvuQaoNJ2xqlZ8AHCR6iaqJtzmPBR6zHLyeCPVpdPJQfcSO7 +9ABzqo8isGxeuaAE7y0WUp0ZsSpdYvdext5SStjtvZ+hKERdVluhBF+OxZIZByp RSBoZJrbTKKpzTUBSE0ci+mlfqBPmSVjjqvygscuwOoKhm+601E51DYb1QXkGujq vuc1f/c7VjTAXyvs9k4An2x3XcN5SFhA6Bhc+L6aU/UJBzAWrJJkVOwS79gHNSn1 qshyhpDLE8MiBEi0QxaEmBZLkz3BX1aYbQA0+5wvgoz0u8QglrpRrPRIWUWC0wvq SOLIibZkJuPUOZuD5AP4tg80swTuSCvyWuiKUVRnJK9FsYKdcyNUCnOLIwUzQlrg 1/hatlvS =cq8V -----END PGP SIGNATURE----- Merge tag 'rcu.next.v6.10' of https://github.com/urezki/linux Pull RCU updates from Uladzislau Rezki: - Fix a lockdep complain for lazy-preemptible kernel, remove redundant BH disable for TINY_RCU, remove redundant READ_ONCE() in tree.c, fix false positives KCSAN splat and fix buffer overflow in the print_cpu_stall_info(). - Misc updates related to bpf, tracing and update the MAINTAINERS file. - An improvement of a normal synchronize_rcu() call in terms of latency. It maintains a separate track for sync. users only. This approach bypasses per-cpu nocb-lists thus sync-users do not depend on nocb-list length and how fast regular callbacks are processed. - RCU tasks: switch tasks RCU grace periods to sleep at TASK_IDLE priority, fix some comments, add some diagnostic warning to the exit_tasks_rcu_start() and fix a buffer overflow in the show_rcu_tasks_trace_gp_kthread(). - RCU torture: Increase memory to guest OS, fix a Tasks Rude RCU testing, some updates for TREE09, dump mode information to debug GP kthread state, remove redundant READ_ONCE(), fix some comments about RCU_TORTURE_PIPE_LEN and pipe_count, remove some redundant pointer initialization, fix a hung splat task by when the rcutorture tests start to exit, fix invalid context warning, add '--do-kvfree' parameter to torture test and use slow register unregister callbacks only for rcutype test. * tag 'rcu.next.v6.10' of https://github.com/urezki/linux: (48 commits) rcutorture: Use rcu_gp_slow_register/unregister() only for rcutype test torture: Scale --do-kvfree test time rcutorture: Fix invalid context warning when enable srcu barrier testing rcutorture: Make stall-tasks directly exit when rcutorture tests end rcutorture: Removing redundant function pointer initialization rcutorture: Make rcutorture support print rcu-tasks gp state rcutorture: Use the gp_kthread_dbg operation specified by cur_ops rcutorture: Re-use value stored to ->rtort_pipe_count instead of re-reading rcutorture: Fix rcu_torture_one_read() pipe_count overflow comment rcutorture: Remove extraneous rcu_torture_pipe_update_one() READ_ONCE() rcu: Allocate WQ with WQ_MEM_RECLAIM bit set rcu: Support direct wake-up of synchronize_rcu() users rcu: Add a trace event for synchronize_rcu_normal() rcu: Reduce synchronize_rcu() latency rcu: Fix buffer overflow in print_cpu_stall_info() rcu: Mollify sparse with RCU guard rcu-tasks: Fix show_rcu_tasks_trace_gp_kthread buffer overflow rcu-tasks: Fix the comments for tasks_rcu_exit_srcu_stall_timer rcu-tasks: Replace exit_tasks_rcu_start() initialization with WARN_ON_ONCE() rcu: Remove redundant CONFIG_PROVE_RCU #if condition ... |
|
Puranjay Mohan
|
2ddec2c80b |
riscv, bpf: inline bpf_get_smp_processor_id()
Inline the calls to bpf_get_smp_processor_id() in the riscv bpf jit.
RISCV saves the pointer to the CPU's task_struct in the TP (thread
pointer) register. This makes it trivial to get the CPU's processor id.
As thread_info is the first member of task_struct, we can read the
processor id from TP + offsetof(struct thread_info, cpu).
RISCV64 JIT output for `call bpf_get_smp_processor_id`
======================================================
Before After
-------- -------
auipc t1,0x848c ld a5,32(tp)
jalr 604(t1)
mv a5,a0
Benchmark using [1] on Qemu.
./benchs/run_bench_trigger.sh glob-arr-inc arr-inc hash-inc
+---------------+------------------+------------------+--------------+
| Name | Before | After | % change |
|---------------+------------------+------------------+--------------|
| glob-arr-inc | 1.077 ± 0.006M/s | 1.336 ± 0.010M/s | + 24.04% |
| arr-inc | 1.078 ± 0.002M/s | 1.332 ± 0.015M/s | + 23.56% |
| hash-inc | 0.494 ± 0.004M/s | 0.653 ± 0.001M/s | + 32.18% |
+---------------+------------------+------------------+--------------+
NOTE: This benchmark includes changes from this patch and the previous
patch that implemented the per-cpu insn.
[1] https://github.com/anakryiko/linux/commit/8dec900975ef
Signed-off-by: Puranjay Mohan <puranjay@kernel.org>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Björn Töpel <bjorn@kernel.org>
Link: https://lore.kernel.org/r/20240502151854.9810-3-puranjay@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
Haiyue Wang
|
75b0fbf15d |
bpf: Remove redundant page mask of vmf->address
As the comment described in "struct vm_fault": ".address" : 'Faulting virtual address - masked' ".real_address" : 'Faulting virtual address - unmasked' The link [1] said: "Whatever the routes, all architectures end up to the invocation of handle_mm_fault() which, in turn, (likely) ends up calling __handle_mm_fault() to carry out the actual work of allocating the page tables." __handle_mm_fault() does address assignment: .address = address & PAGE_MASK, .real_address = address, This is debug dump by running `./test_progs -a "*arena*"`: [ 69.767494] arena fault: vmf->address = 10000001d000, vmf->real_address = 10000001d008 [ 69.767496] arena fault: vmf->address = 10000001c000, vmf->real_address = 10000001c008 [ 69.767499] arena fault: vmf->address = 10000001b000, vmf->real_address = 10000001b008 [ 69.767501] arena fault: vmf->address = 10000001a000, vmf->real_address = 10000001a008 [ 69.767504] arena fault: vmf->address = 100000019000, vmf->real_address = 100000019008 [ 69.769388] arena fault: vmf->address = 10000001e000, vmf->real_address = 10000001e1e8 So we can use the value of 'vmf->address' to do BPF arena kernel address space cast directly. [1] https://docs.kernel.org/mm/page_tables.html Signed-off-by: Haiyue Wang <haiyue.wang@intel.com> Link: https://lore.kernel.org/r/20240507063358.8048-1-haiyue.wang@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Cupertino Miranda
|
41d047a871 |
bpf/verifier: relax MUL range computation check
MUL instruction required that src_reg would be a known value (i.e. src_reg would be a const value). The condition in this case can be relaxed, since the range computation algorithm used in current code already supports a proper range computation for any valid range value on its operands. Signed-off-by: Cupertino Miranda <cupertino.miranda@oracle.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Andrii Nakryiko <andrii.nakryiko@gmail.com> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: David Faust <david.faust@oracle.com> Cc: Jose Marchesi <jose.marchesi@oracle.com> Cc: Elena Zannoni <elena.zannoni@oracle.com> Link: https://lore.kernel.org/r/20240506141849.185293-6-cupertino.miranda@oracle.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Cupertino Miranda
|
138cc42c05 |
bpf/verifier: improve XOR and OR range computation
Range for XOR and OR operators would not be attempted unless src_reg would resolve to a single value, i.e. a known constant value. This condition is unnecessary, and the following XOR/OR operator handling could compute a possible better range. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Cupertino Miranda <cupertino.miranda@oracle.com Acked-by: Eduard Zingerman <eddyz87@gmail.com> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: David Faust <david.faust@oracle.com> Cc: Jose Marchesi <jose.marchesi@oracle.com> Cc: Elena Zannoni <elena.zannoni@oracle.com> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com> Link: https://lore.kernel.org/r/20240506141849.185293-4-cupertino.miranda@oracle.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Cupertino Miranda
|
0922c78f59 |
bpf/verifier: refactor checks for range computation
Split range computation checks in its own function, isolating pessimitic range set for dst_reg and failing return to a single point. Signed-off-by: Cupertino Miranda <cupertino.miranda@oracle.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com> Cc: David Faust <david.faust@oracle.com> Cc: Jose Marchesi <jose.marchesi@oracle.com> Cc: Elena Zannoni <elena.zannoni@oracle.com> Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com> bpf/verifier: improve code after range computation recent changes. Link: https://lore.kernel.org/r/20240506141849.185293-3-cupertino.miranda@oracle.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Cupertino Miranda
|
d786957ebd |
bpf/verifier: replace calls to mark_reg_unknown.
In order to further simplify the code in adjust_scalar_min_max_vals all
the calls to mark_reg_unknown are replaced by __mark_reg_unknown.
static void mark_reg_unknown(struct bpf_verifier_env *env,
struct bpf_reg_state *regs, u32 regno)
{
if (WARN_ON(regno >= MAX_BPF_REG)) {
... mark all regs not init ...
return;
}
__mark_reg_unknown(env, regs + regno);
}
The 'regno >= MAX_BPF_REG' does not apply to
adjust_scalar_min_max_vals(), because it is only called from the
following stack:
- check_alu_op
- adjust_reg_min_max_vals
- adjust_scalar_min_max_vals
The check_alu_op() does check_reg_arg() which verifies that both src and
dst register numbers are within bounds.
Signed-off-by: Cupertino Miranda <cupertino.miranda@oracle.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Cc: Yonghong Song <yonghong.song@linux.dev>
Cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: David Faust <david.faust@oracle.com>
Cc: Jose Marchesi <jose.marchesi@oracle.com>
Cc: Elena Zannoni <elena.zannoni@oracle.com>
Cc: Andrii Nakryiko <andrii.nakryiko@gmail.com>
Link: https://lore.kernel.org/r/20240506141849.185293-2-cupertino.miranda@oracle.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Jakub Kicinski
|
e958da0ddb |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: include/linux/filter.h kernel/bpf/core.c |
|
|
Vadim Fedorenko
|
ac2f438c2a |
bpf: crypto: fix build when CONFIG_CRYPTO=m
Crypto subsytem can be build as a module. In this case we still have to
build BPF crypto framework otherwise the build will fail.
Fixes:
|
|
Stanislav Fomichev
|
543576ec15 |
bpf: Add BPF_PROG_TYPE_CGROUP_SKB attach type enforcement in BPF_LINK_CREATE
bpf_prog_attach uses attach_type_to_prog_type to enforce proper
attach type for BPF_PROG_TYPE_CGROUP_SKB. link_create uses
bpf_prog_get and relies on bpf_prog_attach_check_attach_type
to properly verify prog_type <> attach_type association.
Add missing attach_type enforcement for the link_create case.
Otherwise, it's currently possible to attach cgroup_skb prog
types to other cgroup hooks.
Fixes:
|
|
|
Jiri Olsa
|
5c919acef8 |
bpf: Add support for kprobe session cookie
Adding support for cookie within the session of kprobe multi entry and return program. The session cookie is u64 value and can be retrieved be new kfunc bpf_session_cookie, which returns pointer to the cookie value. The bpf program can use the pointer to store (on entry) and load (on return) the value. The cookie value is implemented via fprobe feature that allows to share values between entry and return ftrace fprobe callbacks. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240430112830.1184228-4-jolsa@kernel.org |
|
|
Jiri Olsa
|
adf46d88ae |
bpf: Add support for kprobe session context
Adding struct bpf_session_run_ctx object to hold session related data, which is atm is_return bool and data pointer coming in following changes. Placing bpf_session_run_ctx layer in between bpf_run_ctx and bpf_kprobe_multi_run_ctx so the session data can be retrieved regardless of if it's kprobe_multi or uprobe_multi link, which support is coming in future. This way both kprobe_multi and uprobe_multi can use same kfuncs to access the session data. Adding bpf_session_is_return kfunc that returns true if the bpf program is executed from the exit probe of the kprobe multi link attached in wrapper mode. It returns false otherwise. Adding new kprobe hook for kprobe program type. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240430112830.1184228-3-jolsa@kernel.org |
|
|
Jiri Olsa
|
535a3692ba |
bpf: Add support for kprobe session attach
Adding support to attach bpf program for entry and return probe of the same function. This is common use case which at the moment requires to create two kprobe multi links. Adding new BPF_TRACE_KPROBE_SESSION attach type that instructs kernel to attach single link program to both entry and exit probe. It's possible to control execution of the bpf program on return probe simply by returning zero or non zero from the entry bpf program execution to execute or not the bpf program on return probe respectively. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240430112830.1184228-2-jolsa@kernel.org |
|
|
Benjamin Tissoires
|
a891711d01 |
bpf: Do not walk twice the hash map on free
If someone stores both a timer and a workqueue in a hash map, on free, we
would walk it twice.
Add a check in htab_free_malloced_timers_or_wq and free the timers and
workqueues if they are present.
Fixes:
|
|
|
Benjamin Tissoires
|
b98a5c68cc |
bpf: Do not walk twice the map on free
If someone stores both a timer and a workqueue in a map, on free
we would walk it twice.
Add a check in array_map_free_timers_wq and free the timers and
workqueues if they are present.
Fixes:
|
|
Andy Shevchenko
|
a3034872cd |
bpf: Switch to krealloc_array()
Let the krealloc_array() copy the original data and check for a multiplication overflow. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/bpf/20240429120005.3539116-1-andriy.shevchenko@linux.intel.com |
|
|
Andy Shevchenko
|
cb01621b6d |
bpf: Use struct_size()
Use struct_size() instead of hand writing it. This is less verbose and more robust. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/bpf/20240429121323.3818497-1-andriy.shevchenko@linux.intel.com |
|
|
Alexei Starovoitov
|
0db63c0b86 |
bpf: Fix verifier assumptions about socket->sk
The verifier assumes that 'sk' field in 'struct socket' is valid
and non-NULL when 'socket' pointer itself is trusted and non-NULL.
That may not be the case when socket was just created and
passed to LSM socket_accept hook.
Fix this verifier assumption and adjust tests.
Reported-by: Liam Wisehart <liamwisehart@meta.com>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Fixes:
|
|
|
Jakub Kicinski
|
89de2db193 |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZi9+AAAKCRDbK58LschI g0nEAP487m7L0nLVriC2oIOWsi29tklW3etm6DO7gmGRGIHgrgEAnMyV1xBj3bGj v6jJwDcybCym1hLx+1x1JCZ4eoAFswE= =xbna -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-04-29 We've added 147 non-merge commits during the last 32 day(s) which contain a total of 158 files changed, 9400 insertions(+), 2213 deletions(-). The main changes are: 1) Add an internal-only BPF per-CPU instruction for resolving per-CPU memory addresses and implement support in x86 BPF JIT. This allows inlining per-CPU array and hashmap lookups and the bpf_get_smp_processor_id() helper, from Andrii Nakryiko. 2) Add BPF link support for sk_msg and sk_skb programs, from Yonghong Song. 3) Optimize x86 BPF JIT's emit_mov_imm64, and add support for various atomics in bpf_arena which can be JITed as a single x86 instruction, from Alexei Starovoitov. 4) Add support for passing mark with bpf_fib_lookup helper, from Anton Protopopov. 5) Add a new bpf_wq API for deferring events and refactor sleepable bpf_timer code to keep common code where possible, from Benjamin Tissoires. 6) Fix BPF_PROG_TEST_RUN infra with regards to bpf_dummy_struct_ops programs to check when NULL is passed for non-NULLable parameters, from Eduard Zingerman. 7) Harden the BPF verifier's and/or/xor value tracking, from Harishankar Vishwanathan. 8) Introduce crypto kfuncs to make BPF programs able to utilize the kernel crypto subsystem, from Vadim Fedorenko. 9) Various improvements to the BPF instruction set standardization doc, from Dave Thaler. 10) Extend libbpf APIs to partially consume items from the BPF ringbuffer, from Andrea Righi. 11) Bigger batch of BPF selftests refactoring to use common network helpers and to drop duplicate code, from Geliang Tang. 12) Support bpf_tail_call_static() helper for BPF programs with GCC 13, from Jose E. Marchesi. 13) Add bpf_preempt_{disable,enable}() kfuncs in order to allow a BPF program to have code sections where preemption is disabled, from Kumar Kartikeya Dwivedi. 14) Allow invoking BPF kfuncs from BPF_PROG_TYPE_SYSCALL programs, from David Vernet. 15) Extend the BPF verifier to allow different input maps for a given bpf_for_each_map_elem() helper call in a BPF program, from Philo Lu. 16) Add support for PROBE_MEM32 and bpf_addr_space_cast instructions for riscv64 and arm64 JITs to enable BPF Arena, from Puranjay Mohan. 17) Shut up a false-positive KMSAN splat in interpreter mode by unpoison the stack memory, from Martin KaFai Lau. 18) Improve xsk selftest coverage with new tests on maximum and minimum hardware ring size configurations, from Tushar Vyavahare. 19) Various ReST man pages fixes as well as documentation and bash completion improvements for bpftool, from Rameez Rehman & Quentin Monnet. 20) Fix libbpf with regards to dumping subsequent char arrays, from Quentin Deslandes. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (147 commits) bpf, docs: Clarify PC use in instruction-set.rst bpf_helpers.h: Define bpf_tail_call_static when building with GCC bpf, docs: Add introduction for use in the ISA Internet Draft selftests/bpf: extend BPF_SOCK_OPS_RTT_CB test for srtt and mrtt_us bpf: add mrtt and srtt as BPF_SOCK_OPS_RTT_CB args selftests/bpf: dummy_st_ops should reject 0 for non-nullable params bpf: check bpf_dummy_struct_ops program params for test runs selftests/bpf: do not pass NULL for non-nullable params in dummy_st_ops selftests/bpf: adjust dummy_st_ops_success to detect additional error bpf: mark bpf_dummy_struct_ops.test_1 parameter as nullable selftests/bpf: Add ring_buffer__consume_n test. bpf: Add bpf_guard_preempt() convenience macro selftests: bpf: crypto: add benchmark for crypto functions selftests: bpf: crypto skcipher algo selftests bpf: crypto: add skcipher to bpf crypto bpf: make common crypto API for TC/XDP programs bpf: update the comment for BTF_FIELDS_MAX selftests/bpf: Fix wq test. selftests/bpf: Use make_sockaddr in test_sock_addr selftests/bpf: Use connect_to_addr in test_sock_addr ... ==================== Link: https://lore.kernel.org/r/20240429131657.19423-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
Puranjay Mohan
|
66e13b615a |
bpf: verifier: prevent userspace memory access
With BPF_PROBE_MEM, BPF allows de-referencing an untrusted pointer. To
thwart invalid memory accesses, the JITs add an exception table entry
for all such accesses. But in case the src_reg + offset is a userspace
address, the BPF program might read that memory if the user has
mapped it.
Make the verifier add guard instructions around such memory accesses and
skip the load if the address falls into the userspace region.
The JITs need to implement bpf_arch_uaddress_limit() to define where
the userspace addresses end for that architecture or TASK_SIZE is taken
as default.
The implementation is as follows:
REG_AX = SRC_REG
if(offset)
REG_AX += offset;
REG_AX >>= 32;
if (REG_AX <= (uaddress_limit >> 32))
DST_REG = 0;
else
DST_REG = *(size *)(SRC_REG + offset);
Comparing just the upper 32 bits of the load address with the upper
32 bits of uaddress_limit implies that the values are being aligned down
to a 4GB boundary before comparison.
The above means that all loads with address <= uaddress_limit + 4GB are
skipped. This is acceptable because there is a large hole (much larger
than 4GB) between userspace and kernel space memory, therefore a
correctly functioning BPF program should not access this 4GB memory
above the userspace.
Let's analyze what this patch does to the following fentry program
dereferencing an untrusted pointer:
SEC("fentry/tcp_v4_connect")
int BPF_PROG(fentry_tcp_v4_connect, struct sock *sk)
{
*(volatile long *)sk;
return 0;
}
BPF Program before | BPF Program after
------------------ | -----------------
0: (79) r1 = *(u64 *)(r1 +0) 0: (79) r1 = *(u64 *)(r1 +0)
-----------------------------------------------------------------------
1: (79) r1 = *(u64 *)(r1 +0) --\ 1: (bf) r11 = r1
----------------------------\ \ 2: (77) r11 >>= 32
2: (b7) r0 = 0 \ \ 3: (b5) if r11 <= 0x8000 goto pc+2
3: (95) exit \ \-> 4: (79) r1 = *(u64 *)(r1 +0)
\ 5: (05) goto pc+1
\ 6: (b7) r1 = 0
\--------------------------------------
7: (b7) r0 = 0
8: (95) exit
As you can see from above, in the best case (off=0), 5 extra instructions
are emitted.
Now, we analyze the same program after it has gone through the JITs of
ARM64 and RISC-V architectures. We follow the single load instruction
that has the untrusted pointer and see what instrumentation has been
added around it.
x86-64 JIT
==========
JIT's Instrumentation
(upstream)
---------------------
0: nopl 0x0(%rax,%rax,1)
5: xchg %ax,%ax
7: push %rbp
8: mov %rsp,%rbp
b: mov 0x0(%rdi),%rdi
---------------------------------
f: movabs $0x800000000000,%r11
19: cmp %r11,%rdi
1c: jb 0x000000000000002a
1e: mov %rdi,%r11
21: add $0x0,%r11
28: jae 0x000000000000002e
2a: xor %edi,%edi
2c: jmp 0x0000000000000032
2e: mov 0x0(%rdi),%rdi
---------------------------------
32: xor %eax,%eax
34: leave
35: ret
The x86-64 JIT already emits some instructions to protect against user
memory access. This patch doesn't make any changes for the x86-64 JIT.
ARM64 JIT
=========
No Intrumentation Verifier's Instrumentation
(upstream) (This patch)
----------------- --------------------------
0: add x9, x30, #0x0 0: add x9, x30, #0x0
4: nop 4: nop
8: paciasp 8: paciasp
c: stp x29, x30, [sp, #-16]! c: stp x29, x30, [sp, #-16]!
10: mov x29, sp 10: mov x29, sp
14: stp x19, x20, [sp, #-16]! 14: stp x19, x20, [sp, #-16]!
18: stp x21, x22, [sp, #-16]! 18: stp x21, x22, [sp, #-16]!
1c: stp x25, x26, [sp, #-16]! 1c: stp x25, x26, [sp, #-16]!
20: stp x27, x28, [sp, #-16]! 20: stp x27, x28, [sp, #-16]!
24: mov x25, sp 24: mov x25, sp
28: mov x26, #0x0 28: mov x26, #0x0
2c: sub x27, x25, #0x0 2c: sub x27, x25, #0x0
30: sub sp, sp, #0x0 30: sub sp, sp, #0x0
34: ldr x0, [x0] 34: ldr x0, [x0]
--------------------------------------------------------------------------------
38: ldr x0, [x0] ----------\ 38: add x9, x0, #0x0
-----------------------------------\\ 3c: lsr x9, x9, #32
3c: mov x7, #0x0 \\ 40: cmp x9, #0x10, lsl #12
40: mov sp, sp \\ 44: b.ls 0x0000000000000050
44: ldp x27, x28, [sp], #16 \\--> 48: ldr x0, [x0]
48: ldp x25, x26, [sp], #16 \ 4c: b 0x0000000000000054
4c: ldp x21, x22, [sp], #16 \ 50: mov x0, #0x0
50: ldp x19, x20, [sp], #16 \---------------------------------------
54: ldp x29, x30, [sp], #16 54: mov x7, #0x0
58: add x0, x7, #0x0 58: mov sp, sp
5c: autiasp 5c: ldp x27, x28, [sp], #16
60: ret 60: ldp x25, x26, [sp], #16
64: nop 64: ldp x21, x22, [sp], #16
68: ldr x10, 0x0000000000000070 68: ldp x19, x20, [sp], #16
6c: br x10 6c: ldp x29, x30, [sp], #16
70: add x0, x7, #0x0
74: autiasp
78: ret
7c: nop
80: ldr x10, 0x0000000000000088
84: br x10
There are 6 extra instructions added in ARM64 in the best case. This will
become 7 in the worst case (off != 0).
RISC-V JIT (RISCV_ISA_C Disabled)
==========
No Intrumentation Verifier's Instrumentation
(upstream) (This patch)
----------------- --------------------------
0: nop 0: nop
4: nop 4: nop
8: li a6, 33 8: li a6, 33
c: addi sp, sp, -16 c: addi sp, sp, -16
10: sd s0, 8(sp) 10: sd s0, 8(sp)
14: addi s0, sp, 16 14: addi s0, sp, 16
18: ld a0, 0(a0) 18: ld a0, 0(a0)
---------------------------------------------------------------
1c: ld a0, 0(a0) --\ 1c: mv t0, a0
--------------------------\ \ 20: srli t0, t0, 32
20: li a5, 0 \ \ 24: lui t1, 4096
24: ld s0, 8(sp) \ \ 28: sext.w t1, t1
28: addi sp, sp, 16 \ \ 2c: bgeu t1, t0, 12
2c: sext.w a0, a5 \ \--> 30: ld a0, 0(a0)
30: ret \ 34: j 8
\ 38: li a0, 0
\------------------------------
3c: li a5, 0
40: ld s0, 8(sp)
44: addi sp, sp, 16
48: sext.w a0, a5
4c: ret
There are 7 extra instructions added in RISC-V.
Fixes:
|
|
Rick Edgecombe
|
529ce23a76 |
mm: switch mm->get_unmapped_area() to a flag
The mm_struct contains a function pointer *get_unmapped_area(), which is set to either arch_get_unmapped_area() or arch_get_unmapped_area_topdown() during the initialization of the mm. Since the function pointer only ever points to two functions that are named the same across all arch's, a function pointer is not really required. In addition future changes will want to add versions of the functions that take additional arguments. So to save a pointers worth of bytes in mm_struct, and prevent adding additional function pointers to mm_struct in future changes, remove it and keep the information about which get_unmapped_area() to use in a flag. Add the new flag to MMF_INIT_MASK so it doesn't get clobbered on fork by mmf_init_flags(). Most MM flags get clobbered on fork. In the pre-existing behavior mm->get_unmapped_area() would get copied to the new mm in dup_mm(), so not clobbering the flag preserves the existing behavior around inheriting the topdown-ness. Introduce a helper, mm_get_unmapped_area(), to easily convert code that refers to the old function pointer to instead select and call either arch_get_unmapped_area() or arch_get_unmapped_area_topdown() based on the flag. Then drop the mm->get_unmapped_area() function pointer. Leave the get_unmapped_area() pointer in struct file_operations alone. The main purpose of this change is to reorganize in preparation for future changes, but it also converts the calls of mm->get_unmapped_area() from indirect branches into a direct ones. The stress-ng bigheap benchmark calls realloc a lot, which calls through get_unmapped_area() in the kernel. On x86, the change yielded a ~1% improvement there on a retpoline config. In testing a few x86 configs, removing the pointer unfortunately didn't result in any actual size reductions in the compiled layout of mm_struct. But depending on compiler or arch alignment requirements, the change could shrink the size of mm_struct. Link: https://lkml.kernel.org/r/20240326021656.202649-3-rick.p.edgecombe@intel.com Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com> Acked-by: Dave Hansen <dave.hansen@linux.intel.com> Acked-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Aneesh Kumar K.V <aneesh.kumar@kernel.org> Cc: Borislav Petkov (AMD) <bp@alien8.de> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Deepak Gupta <debug@rivosinc.com> Cc: Guo Ren <guoren@kernel.org> Cc: Helge Deller <deller@gmx.de> Cc: H. Peter Anvin (Intel) <hpa@zytor.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Kees Cook <keescook@chromium.org> Cc: Mark Brown <broonie@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
|
Yosry Ahmed
|
91b71e78b8 |
mm: memcg: add NULL check to obj_cgroup_put()
9 out of 16 callers perform a NULL check before calling obj_cgroup_put(). Move the NULL check in the function, similar to mem_cgroup_put(). The unlikely() NULL check in current_objcg_update() was left alone to avoid dropping the unlikey() annotation as this a fast path. Link: https://lkml.kernel.org/r/20240316015803.2777252-1-yosryahmed@google.com Signed-off-by: Yosry Ahmed <yosryahmed@google.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
|
|
Vadim Fedorenko
|
3e1c6f3540 |
bpf: make common crypto API for TC/XDP programs
Add crypto API support to BPF to be able to decrypt or encrypt packets in TC/XDP BPF programs. Special care should be taken for initialization part of crypto algo because crypto alloc) doesn't work with preemtion disabled, it can be run only in sleepable BPF program. Also async crypto is not supported because of the very same issue - TC/XDP BPF programs are not sleepable. Signed-off-by: Vadim Fedorenko <vadfed@meta.com> Link: https://lore.kernel.org/r/20240422225024.2847039-2-vadfed@meta.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kumar Kartikeya Dwivedi
|
fc7566ad0a |
bpf: Introduce bpf_preempt_[disable,enable] kfuncs
Introduce two new BPF kfuncs, bpf_preempt_disable and bpf_preempt_enable. These kfuncs allow disabling preemption in BPF programs. Nesting is allowed, since the intended use cases includes building native BPF spin locks without kernel helper involvement. Apart from that, this can be used to per-CPU data structures for cases where programs (or userspace) may preempt one or the other. Currently, while per-CPU access is stable, whether it will be consistent is not guaranteed, as only migration is disabled for BPF programs. Global functions are disallowed from being called, but support for them will be added as a follow up not just preempt kfuncs, but rcu_read_lock kfuncs as well. Static subprog calls are permitted. Sleepable helpers and kfuncs are disallowed in non-preemptible regions. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20240424031315.2757363-2-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Alexei Starovoitov
|
dc92febf7b |
bpf: Don't check for recursion in bpf_wq_work.
__bpf_prog_enter_sleepable_recur does recursion check which is not applicable
to wq callback. The callback function is part of bpf program and bpf prog might
be running on the same cpu. So recursion check would incorrectly prevent
callback from running. The code can call __bpf_prog_enter_sleepable(), but
run_ctx would be fake, hence use explicit rcu_read_lock_trace();
migrate_disable(); to address this problem. Another reason to open code is
__bpf_prog_enter* are not available in !JIT configs.
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202404241719.IIGdpAku-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202404241811.FFV4Bku3-lkp@intel.com/
Fixes:
|
|
|
Joel Granados
|
1adb825af9 |
bpf: Remove the now superfluous sentinel elements from ctl_table array
This commit comes at the tail end of a greater effort to remove the empty elements at the end of the ctl_table arrays (sentinels) which will reduce the overall build time size of the kernel and run time memory bloat by ~64 bytes per sentinel (further information Link : https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/) Remove sentinel element from bpf_syscall_table. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Joel Granados <j.granados@samsung.com> |
|
|
Benjamin Tissoires
|
8e83da9732 |
bpf: add bpf_wq_start
again, copy/paste from bpf_timer_start(). Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-15-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
81f1d7a583 |
bpf: wq: add bpf_wq_set_callback_impl
To support sleepable async callbacks, we need to tell push_async_cb() whether the cb is sleepable or not. The verifier now detects that we are in bpf_wq_set_callback_impl and can allow a sleepable callback to happen. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-13-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
eb48f6cd41 |
bpf: wq: add bpf_wq_init
We need to teach the verifier about the second argument which is declared as void * but which is of type KF_ARG_PTR_TO_MAP. We could have dropped this extra case if we declared the second argument as struct bpf_map *, but that means users will have to do extra casting to have their program compile. We also need to duplicate the timer code for the checking if the map argument is matching the provided workqueue. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-11-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
246331e3f1 |
bpf: allow struct bpf_wq to be embedded in arraymaps and hashmaps
Currently bpf_wq_cancel_and_free() is just a placeholder as there is no memory allocation for bpf_wq just yet. Again, duplication of the bpf_timer approach Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-9-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
d940c9b94d |
bpf: add support for KF_ARG_PTR_TO_WORKQUEUE
Introduce support for KF_ARG_PTR_TO_WORKQUEUE. The kfuncs will use bpf_wq as argument and that will be recognized as workqueue argument by verifier. bpf_wq_kern casting can happen inside kfunc, but using bpf_wq in argument makes life easier for users who work with non-kern type in BPF progs. Duplicate process_timer_func into process_wq_func. meta argument is only needed to ensure bpf_wq_init's workqueue and map arguments are coming from the same map (map_uid logic is necessary for correct inner-map handling), so also amend check_kfunc_args() to match what helpers functions check is doing. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-8-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
ad2c03e691 |
bpf: verifier: bail out if the argument is not a map
When a kfunc is declared with a KF_ARG_PTR_TO_MAP, we should have reg->map_ptr set to a non NULL value, otherwise, that means that the underlying type is not a map. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-7-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
d56b63cf0c |
bpf: add support for bpf_wq user type
Mostly a copy/paste from the bpf_timer API, without the initialization and free, as they will be done in a separate patch. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-5-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
fc22d9495f |
bpf: replace bpf_timer_cancel_and_free with a generic helper
Same reason than most bpf_timer* functions, we need almost the same for workqueues. So extract the generic part out of it so bpf_wq_cancel_and_free can reuse it. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-4-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
073f11b026 |
bpf: replace bpf_timer_set_callback with a generic helper
In the same way we have a generic __bpf_async_init(), we also need to share code between timer and workqueue for the set_callback call. We just add an unused flags parameter, as it will be used for workqueues. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-3-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
56b4a177ae |
bpf: replace bpf_timer_init with a generic helper
No code change except for the new flags argument being stored in the local data struct. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-2-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
be2749beff |
bpf: make timer data struct more generic
To be able to add workqueues and reuse most of the timer code, we need to make bpf_hrtimer more generic. There is no code change except that the new struct gets a new u64 flags attribute. We are still below 2 cache lines, so this shouldn't impact the current running codes. The ordering is also changed. Everything related to async callback is now on top of bpf_hrtimer. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240420-bpf_wq-v2-1-6c986a5a741f@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Rafael Passos
|
a7de265cb2 |
bpf: Fix typos in comments
Found the following typos in comments, and fixed them: s/unpriviledged/unprivileged/ s/reponsible/responsible/ s/possiblities/possibilities/ s/Divison/Division/ s/precsion/precision/ s/havea/have a/ s/reponsible/responsible/ s/responsibile/responsible/ s/tigher/tighter/ s/respecitve/respective/ Signed-off-by: Rafael Passos <rafael@rcpassos.me> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/6af7deb4-bb24-49e8-b3f1-8dd410597337@smtp-relay.sendinblue.com |
|
|
Rafael Passos
|
e1a7545981 |
bpf: Fix typo in function save_aux_ptr_type
I found this typo in the save_aux_ptr_type function. s/allow_trust_missmatch/allow_trust_mismatch/ I did not find this anywhere else in the codebase. Signed-off-by: Rafael Passos <rafael@rcpassos.me> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/fbe1d636-8172-4698-9a5a-5a3444b55322@smtp-relay.sendinblue.com |
|
Harishankar Vishwanathan
|
1f586614f3 |
bpf: Harden and/or/xor value tracking in verifier
This patch addresses a latent unsoundness issue in the scalar(32)_min_max_and/or/xor functions. While it is not a bugfix, it ensures that the functions produce sound outputs for all inputs. The issue occurs in these functions when setting signed bounds. The following example illustrates the issue for scalar_min_max_and(), but it applies to the other functions. In scalar_min_max_and() the following clause is executed when ANDing positive numbers: /* ANDing two positives gives a positive, so safe to * cast result into s64. */ dst_reg->smin_value = dst_reg->umin_value; dst_reg->smax_value = dst_reg->umax_value; However, if umin_value and umax_value of dst_reg cross the sign boundary (i.e., if (s64)dst_reg->umin_value > (s64)dst_reg->umax_value), then we will end up with smin_value > smax_value, which is unsound. Previous works [1, 2] have discovered and reported this issue. Our tool Agni [2, 3] consideres it a false positive. This is because, during the verification of the abstract operator scalar_min_max_and(), Agni restricts its inputs to those passing through reg_bounds_sync(). This mimics real-world verifier behavior, as reg_bounds_sync() is invariably executed at the tail of every abstract operator. Therefore, such behavior is unlikely in an actual verifier execution. However, it is still unsound for an abstract operator to set signed bounds such that smin_value > smax_value. This patch fixes it, making the abstract operator sound for all (well-formed) inputs. It is worth noting that while the previous code updated the signed bounds (using the output unsigned bounds) only when the *input signed* bounds were positive, the new code updates them whenever the *output unsigned* bounds do not cross the sign boundary. An alternative approach to fix this latent unsoundness would be to unconditionally set the signed bounds to unbounded [S64_MIN, S64_MAX], and let reg_bounds_sync() refine the signed bounds using the unsigned bounds and the tnum. We found that our approach produces more precise (tighter) bounds. For example, consider these inputs to BPF_AND: /* dst_reg */ var_off.value: 8608032320201083347 var_off.mask: 615339716653692460 smin_value: 8070450532247928832 smax_value: 8070450532247928832 umin_value: 13206380674380886586 umax_value: 13206380674380886586 s32_min_value: -2110561598 s32_max_value: -133438816 u32_min_value: 4135055354 u32_max_value: 4135055354 /* src_reg */ var_off.value: 8584102546103074815 var_off.mask: 9862641527606476800 smin_value: 2920655011908158522 smax_value: 7495731535348625717 umin_value: 7001104867969363969 umax_value: 8584102543730304042 s32_min_value: -2097116671 s32_max_value: 71704632 u32_min_value: 1047457619 u32_max_value: 4268683090 After going through tnum_and() -> scalar32_min_max_and() -> scalar_min_max_and() -> reg_bounds_sync(), our patch produces the following bounds for s32: s32_min_value: -1263875629 s32_max_value: -159911942 Whereas, setting the signed bounds to unbounded in scalar_min_max_and() produces: s32_min_value: -1263875629 s32_max_value: -1 As observed, our patch produces a tighter s32 bound. We also confirmed using Agni and SMT verification that our patch always produces signed bounds that are equal to or more precise than setting the signed bounds to unbounded in scalar_min_max_and(). [1] https://sanjit-bhat.github.io/assets/pdf/ebpf-verifier-range-analysis22.pdf [2] https://link.springer.com/chapter/10.1007/978-3-031-37709-9_12 [3] https://github.com/bpfverif/agni Co-developed-by: Matan Shachnai <m.shachnai@rutgers.edu> Signed-off-by: Matan Shachnai <m.shachnai@rutgers.edu> Co-developed-by: Srinivas Narayana <srinivas.narayana@rutgers.edu> Signed-off-by: Srinivas Narayana <srinivas.narayana@rutgers.edu> Co-developed-by: Santosh Nagarakatte <santosh.nagarakatte@rutgers.edu> Signed-off-by: Santosh Nagarakatte <santosh.nagarakatte@rutgers.edu> Signed-off-by: Harishankar Vishwanathan <harishankar.vishwanathan@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20240402212039.51815-1-harishankar.vishwanathan@gmail.com Link: https://lore.kernel.org/bpf/20240416115303.331688-1-harishankar.vishwanathan@gmail.com |
|
Ard Biesheuvel
|
fc5eb4a84e |
btf: Avoid weak external references
If the BTF code is enabled in the build configuration, the start/stop BTF markers are guaranteed to exist. Only when CONFIG_DEBUG_INFO_BTF=n, the references in btf_parse_vmlinux() will remain unsatisfied, relying on the weak linkage of the external references to avoid breaking the build. Avoid GOT based relocations to these markers in the final executable by dropping the weak attribute and instead, make btf_parse_vmlinux() return ERR_PTR(-ENOENT) directly if CONFIG_DEBUG_INFO_BTF is not enabled to begin with. The compiler will drop any subsequent references to __start_BTF and __stop_BTF in that case, allowing the link to succeed. Note that Clang will notice that taking the address of __start_BTF can no longer yield NULL, so testing for that condition becomes unnecessary. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20240415162041.2491523-8-ardb+git@google.com |
|
Anton Protopopov
|
37eacb9f6e |
bpf: Fix a verifier verbose message
Long ago a map file descriptor in a pseudo ldimm64 instruction could
only be present as an immediate value insn[0].imm, and thus this value
was used in a verbose verifier message printed when the file descriptor
wasn't valid. Since addition of BPF_PSEUDO_MAP_IDX_VALUE/BPF_PSEUDO_MAP_IDX
the insn[0].imm field can also contain an index pointing to the file
descriptor in the attr.fd_array array. However, if the file descriptor
is invalid, the verifier still prints the verbose message containing
value of insn[0].imm. Patch the verifier message to always print the
actual file descriptor value.
Fixes:
|
|
Paul E. McKenney
|
1e52af7f02 |
bpf: Choose RCU Tasks based on TASKS_RCU rather than PREEMPTION
The advent of CONFIG_PREEMPT_AUTO, AKA lazy preemption, will mean that even kernels built with CONFIG_PREEMPT_NONE or CONFIG_PREEMPT_VOLUNTARY might see the occasional preemption, and that this preemption just might happen within a trampoline. Therefore, update bpf_tramp_image_put() to choose call_rcu_tasks() based on CONFIG_TASKS_RCU instead of CONFIG_PREEMPTION. This change might enable further simplifications, but the goal of this effort is to make the code safe, not necessarily optimal. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: John Fastabend <john.fastabend@gmail.com> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Song Liu <song@kernel.org> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: KP Singh <kpsingh@kernel.org> Cc: Stanislav Fomichev <sdf@google.com> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Ankur Arora <ankur.a.arora@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: <bpf@vger.kernel.org> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> |
|
|
Yonghong Song
|
699c23f02c |
bpf: Add bpf_link support for sk_msg and sk_skb progs
Add bpf_link support for sk_msg and sk_skb programs. We have an internal request to support bpf_link for sk_msg programs so user space can have a uniform handling with bpf_link based libbpf APIs. Using bpf_link based libbpf API also has a benefit which makes system robust by decoupling prog life cycle and attachment life cycle. Reviewed-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240410043527.3737160-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Alexei Starovoitov
|
d503a04f8b |
bpf: Add support for certain atomics in bpf_arena to x86 JIT
Support atomics in bpf_arena that can be JITed as a single x86 instruction. Instructions that are JITed as loops are not supported at the moment, since they require more complex extable and loop logic. JITs can choose to do smarter things with bpf_jit_supports_insn(). Like arm64 may decide to support all bpf atomics instructions when emit_lse_atomic is available and none in ll_sc mode. bpf_jit_supports_percpu_insn(), bpf_jit_supports_ptr_xchg() and other such callbacks can be replaced with bpf_jit_supports_insn() in the future. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240405231134.17274-1-alexei.starovoitov@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Paul E. McKenney
|
b993115b44 |
bpf: Select new NEED_TASKS_RCU Kconfig option
Currently, if a Kconfig option depends on TASKS_RCU, it conditionally does "select TASKS_RCU if PREEMPTION". This works, but requires any change in this enablement logic to be replicated across all such "select" clauses. A new NEED_TASKS_RCU Kconfig option has been created to allow this enablement logic to be in one place in kernel/rcu/Kconfig. Therefore, make BPF select the new NEED_TASKS_RCU Kconfig option. Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: Martin KaFai Lau <martin.lau@linux.dev> Cc: Song Liu <song@kernel.org> Cc: Yonghong Song <yonghong.song@linux.dev> Cc: John Fastabend <john.fastabend@gmail.com> Cc: KP Singh <kpsingh@kernel.org> Cc: Stanislav Fomichev <sdf@google.com> Cc: Hao Luo <haoluo@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: <bpf@vger.kernel.org> Cc: Ankur Arora <ankur.a.arora@oracle.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> |
|
David Vernet
|
a8e03b6bbb |
bpf: Allow invoking kfuncs from BPF_PROG_TYPE_SYSCALL progs
Currently, a set of core BPF kfuncs (e.g. bpf_task_*, bpf_cgroup_*, bpf_cpumask_*, etc) cannot be invoked from BPF_PROG_TYPE_SYSCALL programs. The whitelist approach taken for enabling kfuncs makes sense: it not safe to call these kfuncs from every program type. For example, it may not be safe to call bpf_task_acquire() in an fentry to free_task(). BPF_PROG_TYPE_SYSCALL, on the other hand, is a perfectly safe program type from which to invoke these kfuncs, as it's a very controlled environment, and we should never be able to run into any of the typical problems such as recursive invoations, acquiring references on freeing kptrs, etc. Being able to invoke these kfuncs would be useful, as BPF_PROG_TYPE_SYSCALL can be invoked with BPF_PROG_RUN, and would therefore enable user space programs to synchronously call into BPF to manipulate these kptrs. This patch therefore enables invoking the aforementioned core kfuncs from BPF_PROG_TYPE_SYSCALL progs. Signed-off-by: David Vernet <void@manifault.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/bpf/20240405143041.632519-2-void@manifault.com |
|
Philo Lu
|
9d482da9e1 |
bpf: allow invoking bpf_for_each_map_elem with different maps
Taking different maps within a single bpf_for_each_map_elem call is not allowed before, because from the second map, bpf_insn_aux_data->map_ptr_state will be marked as *poison*. In fact both map_ptr and state are needed to support this use case: map_ptr is used by set_map_elem_callback_state() while poison state is needed to determine whether to use direct call. Signed-off-by: Philo Lu <lulie@linux.alibaba.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240405025536.18113-3-lulie@linux.alibaba.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Philo Lu
|
0a525621b7 |
bpf: store both map ptr and state in bpf_insn_aux_data
Currently, bpf_insn_aux_data->map_ptr_state is used to store either map_ptr or its poison state (i.e., BPF_MAP_PTR_POISON). Thus BPF_MAP_PTR_POISON must be checked before reading map_ptr. In certain cases, we may need valid map_ptr even in case of poison state. This will be explained in next patch with bpf_for_each_map_elem() helper. This patch changes map_ptr_state into a new struct including both map pointer and its state (poison/unpriv). It's in the same union with struct bpf_loop_inline_state, so there is no extra memory overhead. Besides, macros BPF_MAP_PTR_UNPRIV/BPF_MAP_PTR_POISON/BPF_MAP_PTR are no longer needed. This patch does not change any existing functionality. Signed-off-by: Philo Lu <lulie@linux.alibaba.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240405025536.18113-2-lulie@linux.alibaba.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Arnd Bergmann
|
58babe2718 |
bpf: fix perf_snapshot_branch_stack link failure
The newly added code to handle bpf_get_branch_snapshot fails to link when
CONFIG_PERF_EVENTS is disabled:
aarch64-linux-ld: kernel/bpf/verifier.o: in function `do_misc_fixups':
verifier.c:(.text+0x1090c): undefined reference to `__SCK__perf_snapshot_branch_stack'
Add a build-time check for that Kconfig symbol around the code to
remove the link time dependency.
Fixes:
|
|
|
Andrii Nakryiko
|
1f2a74b41e |
bpf: prevent r10 register from being marked as precise
r10 is a special register that is not under BPF program's control and is
always effectively precise. The rest of precision logic assumes that
only r0-r9 SCALAR registers are marked as precise, so prevent r10 from
being marked precise.
This can happen due to signed cast instruction allowing to do something
like `r0 = (s8)r10;`, which later, if r0 needs to be precise, would lead
to an attempt to mark r10 as precise.
Prevent this with an extra check during instruction backtracking.
Fixes:
|
|
|
Jakub Kicinski
|
cf1ca1f66d |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: net/ipv4/ip_gre.c |
|
|
Linus Torvalds
|
c88b9b4cde |
Including fixes from netfilter, bluetooth and bpf.
Fairly usual collection of driver and core fixes. The large selftest
accompanying one of the fixes is also becoming a common occurrence.
Current release - regressions:
- ipv6: fix infinite recursion in fib6_dump_done()
- net/rds: fix possible null-deref in newly added error path
Current release - new code bugs:
- net: do not consume a full cacheline for system_page_pool
- bpf: fix bpf_arena-related file descriptor leaks in the verifier
- drv: ice: fix freeing uninitialized pointers, fixing misuse of
the newfangled __free() auto-cleanup
Previous releases - regressions:
- x86/bpf: fixes the BPF JIT with retbleed=stuff
- xen-netfront: add missing skb_mark_for_recycle, fix page pool
accounting leaks, revealed by recently added explicit warning
- tcp: fix bind() regression for v6-only wildcard and v4-mapped-v6
non-wildcard addresses
- Bluetooth:
- replace "hci_qca: Set BDA quirk bit if fwnode exists in DT"
with better workarounds to un-break some buggy Qualcomm devices
- set conn encrypted before conn establishes, fix re-connecting
to some headsets which use slightly unusual sequence of msgs
- mptcp:
- prevent BPF accessing lowat from a subflow socket
- don't account accept() of non-MPC client as fallback to TCP
- drv: mana: fix Rx DMA datasize and skb_over_panic
- drv: i40e: fix VF MAC filter removal
Previous releases - always broken:
- gro: various fixes related to UDP tunnels - netns crossing problems,
incorrect checksum conversions, and incorrect packet transformations
which may lead to panics
- bpf: support deferring bpf_link dealloc to after RCU grace period
- nf_tables:
- release batch on table validation from abort path
- release mutex after nft_gc_seq_end from abort path
- flush pending destroy work before exit_net release
- drv: r8169: skip DASH fw status checks when DASH is disabled
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=6bQI
-----END PGP SIGNATURE-----
Merge tag 'net-6.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from netfilter, bluetooth and bpf.
Fairly usual collection of driver and core fixes. The large selftest
accompanying one of the fixes is also becoming a common occurrence.
Current release - regressions:
- ipv6: fix infinite recursion in fib6_dump_done()
- net/rds: fix possible null-deref in newly added error path
Current release - new code bugs:
- net: do not consume a full cacheline for system_page_pool
- bpf: fix bpf_arena-related file descriptor leaks in the verifier
- drv: ice: fix freeing uninitialized pointers, fixing misuse of the
newfangled __free() auto-cleanup
Previous releases - regressions:
- x86/bpf: fixes the BPF JIT with retbleed=stuff
- xen-netfront: add missing skb_mark_for_recycle, fix page pool
accounting leaks, revealed by recently added explicit warning
- tcp: fix bind() regression for v6-only wildcard and v4-mapped-v6
non-wildcard addresses
- Bluetooth:
- replace "hci_qca: Set BDA quirk bit if fwnode exists in DT" with
better workarounds to un-break some buggy Qualcomm devices
- set conn encrypted before conn establishes, fix re-connecting to
some headsets which use slightly unusual sequence of msgs
- mptcp:
- prevent BPF accessing lowat from a subflow socket
- don't account accept() of non-MPC client as fallback to TCP
- drv: mana: fix Rx DMA datasize and skb_over_panic
- drv: i40e: fix VF MAC filter removal
Previous releases - always broken:
- gro: various fixes related to UDP tunnels - netns crossing
problems, incorrect checksum conversions, and incorrect packet
transformations which may lead to panics
- bpf: support deferring bpf_link dealloc to after RCU grace period
- nf_tables:
- release batch on table validation from abort path
- release mutex after nft_gc_seq_end from abort path
- flush pending destroy work before exit_net release
- drv: r8169: skip DASH fw status checks when DASH is disabled"
* tag 'net-6.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (81 commits)
netfilter: validate user input for expected length
net/sched: act_skbmod: prevent kernel-infoleak
net: usb: ax88179_178a: avoid the interface always configured as random address
net: dsa: sja1105: Fix parameters order in sja1110_pcs_mdio_write_c45()
net: ravb: Always update error counters
net: ravb: Always process TX descriptor ring
netfilter: nf_tables: discard table flag update with pending basechain deletion
netfilter: nf_tables: Fix potential data-race in __nft_flowtable_type_get()
netfilter: nf_tables: reject new basechain after table flag update
netfilter: nf_tables: flush pending destroy work before exit_net release
netfilter: nf_tables: release mutex after nft_gc_seq_end from abort path
netfilter: nf_tables: release batch on table validation from abort path
Revert "tg3: Remove residual error handling in tg3_suspend"
tg3: Remove residual error handling in tg3_suspend
net: mana: Fix Rx DMA datasize and skb_over_panic
net/sched: fix lockdep splat in qdisc_tree_reduce_backlog()
net: phy: micrel: lan8814: Fix when enabling/disabling 1-step timestamping
net: stmmac: fix rx queue priority assignment
net: txgbe: fix i2c dev name cannot match clkdev
net: fec: Set mac_managed_pm during probe
...
|
|
|
Andrii Nakryiko
|
314a53623c |
bpf: inline bpf_get_branch_snapshot() helper
Inline bpf_get_branch_snapshot() helper using architecture-agnostic inline BPF code which calls directly into underlying callback of perf_snapshot_branch_stack static call. This callback is set early during kernel initialization and is never updated or reset, so it's ok to fetch actual implementation using static_call_query() and call directly into it. This change eliminates a full function call and saves one LBR entry in PERF_SAMPLE_BRANCH_ANY LBR mode. Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240404002640.1774210-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Alexei Starovoitov
|
af682b767a |
bpf: Optimize emit_mov_imm64().
Turned out that bpf prog callback addresses, bpf prog addresses used in bpf_trampoline, and in other cases the 64-bit address can be represented as sign extended 32-bit value. According to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82339 "Skylake has 0.64c throughput for mov r64, imm64, vs. 0.25 for mov r32, imm32." So use shorter encoding and faster instruction when possible. Special care is needed in jit_subprogs(), since bpf_pseudo_func() instruction cannot change its size during the last step of JIT. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/CAADnVQKFfpY-QZBrOU2CG8v2du8Lgyb7MNVmOZVK_yTyOdNbBA@mail.gmail.com Link: https://lore.kernel.org/bpf/20240401233800.42737-1-alexei.starovoitov@gmail.com |
|
|
Andrii Nakryiko
|
0b56e637f7 |
bpf: inline bpf_map_lookup_elem() helper for PERCPU_HASH map
Using new per-CPU BPF instruction, partially inline bpf_map_lookup_elem() helper for per-CPU hashmap BPF map. Just like for normal HASH map, we still generate a call into __htab_map_lookup_elem(), but after that we resolve per-CPU element address using a new instruction, saving on extra functions calls. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/r/20240402021307.1012571-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
db69718b8e |
bpf: inline bpf_map_lookup_elem() for PERCPU_ARRAY maps
Using new per-CPU BPF instruction implement inlining for per-CPU ARRAY map lookup helper, if BPF JIT support is present. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/r/20240402021307.1012571-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
1ae6921009 |
bpf: inline bpf_get_smp_processor_id() helper
If BPF JIT supports per-CPU MOV instruction, inline bpf_get_smp_processor_id() to eliminate unnecessary function calls. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/r/20240402021307.1012571-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
7bdbf74463 |
bpf: add special internal-only MOV instruction to resolve per-CPU addrs
Add a new BPF instruction for resolving absolute addresses of per-CPU data from their per-CPU offsets. This instruction is internal-only and users are not allowed to use them directly. They will only be used for internal inlining optimizations for now between BPF verifier and BPF JITs. We use a special BPF_MOV | BPF_ALU64 | BPF_X form with insn->off field set to BPF_ADDR_PERCPU = -1. I used negative offset value to distinguish them from positive ones used by user-exposed instructions. Such instruction performs a resolution of a per-CPU offset stored in a register to a valid kernel address which can be dereferenced. It is useful in any use case where absolute address of a per-CPU data has to be resolved (e.g., in inlining bpf_map_lookup_elem()). BPF disassembler is also taught to recognize them to support dumping final BPF assembly code (non-JIT'ed version). Add arch-specific way for BPF JITs to mark support for this instructions. This patch also adds support for these instructions in x86-64 BPF JIT. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/r/20240402021307.1012571-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Justin Stitt
|
2e114248e0 |
bpf: Replace deprecated strncpy with strscpy
strncpy() is deprecated for use on NUL-terminated destination strings
[1] and as such we should prefer more robust and less ambiguous string
interfaces.
bpf sym names get looked up and compared/cleaned with various string
apis. This suggests they need to be NUL-terminated (strncpy() suggests
this but does not guarantee it).
| static int compare_symbol_name(const char *name, char *namebuf)
| {
| cleanup_symbol_name(namebuf);
| return strcmp(name, namebuf);
| }
| static void cleanup_symbol_name(char *s)
| {
| ...
| res = strstr(s, ".llvm.");
| ...
| }
Use strscpy() as this method guarantees NUL-termination on the
destination buffer.
This patch also replaces two uses of strncpy() used in log.c. These are
simple replacements as postfix has been zero-initialized on the stack
and has source arguments with a size less than the destination's size.
Note that this patch uses the new 2-argument version of strscpy
introduced in commit
|
|
Jose Fernandez
|
ce09cbdd98 |
bpf: Improve program stats run-time calculation
This patch improves the run-time calculation for program stats by capturing the duration as soon as possible after the program returns. Previously, the duration included u64_stats_t operations. While the instrumentation overhead is part of the total time spent when stats are enabled, distinguishing between the program's native execution time and the time spent due to instrumentation is crucial for accurate performance analysis. By making this change, the patch facilitates more precise optimization of BPF programs, enabling users to understand their performance in environments without stats enabled. I used a virtualized environment to measure the run-time over one minute for a basic raw_tracepoint/sys_enter program, which just increments a local counter. Although the virtualization introduced some performance degradation that could affect the results, I observed approximately a 16% decrease in average run-time reported by stats with this change (310 -> 260 nsec). Signed-off-by: Jose Fernandez <josef@netflix.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20240402034010.25060-1-josef@netflix.com |
|
|
Anton Protopopov
|
9dc182c58b |
bpf: Add a verbose message if map limit is reached
When more than 64 maps are used by a program and its subprograms the verifier returns -E2BIG. Add a verbose message which highlights the source of the error and also print the actual limit. Signed-off-by: Anton Protopopov <aspsk@isovalent.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yonghong.song@linux.dev> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20240402073347.195920-1-aspsk@isovalent.com |
|
|
Linus Torvalds
|
7e40c2100c |
Kbuild fixes for v6.9
- Deduplicate Kconfig entries for CONFIG_CXL_PMU
- Fix unselectable choice entry in MIPS Kconfig, and forbid this
structure
- Remove unused include/asm-generic/export.h
- Fix a NULL pointer dereference bug in modpost
- Enable -Woverride-init warning consistently with W=1
- Drop KCSAN flags from *.mod.c files
-----BEGIN PGP SIGNATURE-----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=tx+2
-----END PGP SIGNATURE-----
Merge tag 'kbuild-fixes-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- Deduplicate Kconfig entries for CONFIG_CXL_PMU
- Fix unselectable choice entry in MIPS Kconfig, and forbid this
structure
- Remove unused include/asm-generic/export.h
- Fix a NULL pointer dereference bug in modpost
- Enable -Woverride-init warning consistently with W=1
- Drop KCSAN flags from *.mod.c files
* tag 'kbuild-fixes-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kconfig: Fix typo HEIGTH to HEIGHT
Documentation/llvm: Note s390 LLVM=1 support with LLVM 18.1.0 and newer
kbuild: Disable KCSAN for autogenerated *.mod.c intermediaries
kbuild: make -Woverride-init warnings more consistent
modpost: do not make find_tosym() return NULL
export.h: remove include/asm-generic/export.h
kconfig: do not reparent the menu inside a choice block
MIPS: move unselectable FIT_IMAGE_FDT_EPM5 out of the "System type" choice
cxl: remove CONFIG_CXL_PMU entry in drivers/cxl/Kconfig
|
|
|
Arnd Bergmann
|
c40845e319 |
kbuild: make -Woverride-init warnings more consistent
The -Woverride-init warn about code that may be intentional or not,
but the inintentional ones tend to be real bugs, so there is a bit of
disagreement on whether this warning option should be enabled by default
and we have multiple settings in scripts/Makefile.extrawarn as well as
individual subsystems.
Older versions of clang only supported -Wno-initializer-overrides with
the same meaning as gcc's -Woverride-init, though all supported versions
now work with both. Because of this difference, an earlier cleanup of
mine accidentally turned the clang warning off for W=1 builds and only
left it on for W=2, while it's still enabled for gcc with W=1.
There is also one driver that only turns the warning off for newer
versions of gcc but not other compilers, and some but not all the
Makefiles still use a cc-disable-warning conditional that is no
longer needed with supported compilers here.
Address all of the above by removing the special cases for clang
and always turning the warning off unconditionally where it got
in the way, using the syntax that is supported by both compilers.
Fixes:
|
|
|
Alexei Starovoitov
|
59f2f84117 |
bpf: Avoid kfree_rcu() under lock in bpf_lpm_trie.
syzbot reported the following lock sequence:
cpu 2:
grabs timer_base lock
spins on bpf_lpm lock
cpu 1:
grab rcu krcp lock
spins on timer_base lock
cpu 0:
grab bpf_lpm lock
spins on rcu krcp lock
bpf_lpm lock can be the same.
timer_base lock can also be the same due to timer migration.
but rcu krcp lock is always per-cpu, so it cannot be the same lock.
Hence it's a false positive.
To avoid lockdep complaining move kfree_rcu() after spin_unlock.
Reported-by: syzbot+1fa663a2100308ab6eab@syzkaller.appspotmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240329171439.37813-1-alexei.starovoitov@gmail.com
|
|
|
Anton Protopopov
|
6dae957c8e |
bpf: fix possible file descriptor leaks in verifier
The resolve_pseudo_ldimm64() function might have leaked file
descriptors when BPF_MAP_TYPE_ARENA was used in a program (some
error paths missed a corresponding fdput). Add missing fdputs.
v2:
remove unrelated changes from the fix
Fixes:
|
|
|
Martin KaFai Lau
|
e8742081db |
bpf: Mark bpf prog stack with kmsan_unposion_memory in interpreter mode
syzbot reported uninit memory usages during map_{lookup,delete}_elem.
==========
BUG: KMSAN: uninit-value in __dev_map_lookup_elem kernel/bpf/devmap.c:441 [inline]
BUG: KMSAN: uninit-value in dev_map_lookup_elem+0xf3/0x170 kernel/bpf/devmap.c:796
__dev_map_lookup_elem kernel/bpf/devmap.c:441 [inline]
dev_map_lookup_elem+0xf3/0x170 kernel/bpf/devmap.c:796
____bpf_map_lookup_elem kernel/bpf/helpers.c:42 [inline]
bpf_map_lookup_elem+0x5c/0x80 kernel/bpf/helpers.c:38
___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:1997
__bpf_prog_run256+0xb5/0xe0 kernel/bpf/core.c:2237
==========
The reproducer should be in the interpreter mode.
The C reproducer is trying to run the following bpf prog:
0: (18) r0 = 0x0
2: (18) r1 = map[id:49]
4: (b7) r8 = 16777216
5: (7b) *(u64 *)(r10 -8) = r8
6: (bf) r2 = r10
7: (07) r2 += -229
^^^^^^^^^^
8: (b7) r3 = 8
9: (b7) r4 = 0
10: (85) call dev_map_lookup_elem#1543472
11: (95) exit
It is due to the "void *key" (r2) passed to the helper. bpf allows uninit
stack memory access for bpf prog with the right privileges. This patch
uses kmsan_unpoison_memory() to mark the stack as initialized.
This should address different syzbot reports on the uninit "void *key"
argument during map_{lookup,delete}_elem.
Reported-by: syzbot+603bcd9b0bf1d94dbb9b@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/000000000000f9ce6d061494e694@google.com/
Reported-by: syzbot+eb02dc7f03dce0ef39f3@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/000000000000a5c69c06147c2238@google.com/
Reported-by: syzbot+b4e65ca24fd4d0c734c3@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/000000000000ac56fb06143b6cfa@google.com/
Reported-by: syzbot+d2b113dc9fea5e1d2848@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/0000000000000d69b206142d1ff7@google.com/
Reported-by: syzbot+1a3cf6f08d68868f9db3@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/0000000000006f876b061478e878@google.com/
Tested-by: syzbot+1a3cf6f08d68868f9db3@syzkaller.appspotmail.com
Suggested-by: Yonghong Song <yonghong.song@linux.dev>
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240328185801.1843078-1-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
1a80dbcb2d |
bpf: support deferring bpf_link dealloc to after RCU grace period
BPF link for some program types is passed as a "context" which can be used by those BPF programs to look up additional information. E.g., for multi-kprobes and multi-uprobes, link is used to fetch BPF cookie values. Because of this runtime dependency, when bpf_link refcnt drops to zero there could still be active BPF programs running accessing link data. This patch adds generic support to defer bpf_link dealloc callback to after RCU GP, if requested. This is done by exposing two different deallocation callbacks, one synchronous and one deferred. If deferred one is provided, bpf_link_free() will schedule dealloc_deferred() callback to happen after RCU GP. BPF is using two flavors of RCU: "classic" non-sleepable one and RCU tasks trace one. The latter is used when sleepable BPF programs are used. bpf_link_free() accommodates that by checking underlying BPF program's sleepable flag, and goes either through normal RCU GP only for non-sleepable, or through RCU tasks trace GP *and* then normal RCU GP (taking into account rcu_trace_implies_rcu_gp() optimization), if BPF program is sleepable. We use this for multi-kprobe and multi-uprobe links, which dereference link during program run. We also preventively switch raw_tp link to use deferred dealloc callback, as upcoming changes in bpf-next tree expose raw_tp link data (specifically, cookie value) to BPF program at runtime as well. Fixes: |
|
|
Yafang Shao
|
ee3bad033d |
bpf: Mitigate latency spikes associated with freeing non-preallocated htab
Following the recent upgrade of one of our BPF programs, we encountered significant latency spikes affecting other applications running on the same host. After thorough investigation, we identified that these spikes were primarily caused by the prolonged duration required to free a non-preallocated htab with approximately 2 million keys. Notably, our kernel configuration lacks the presence of CONFIG_PREEMPT. In scenarios where kernel execution extends excessively, other threads might be starved of CPU time, resulting in latency issues across the system. To mitigate this, we've adopted a proactive approach by incorporating cond_resched() calls within the kernel code. This ensures that during lengthy kernel operations, the scheduler is invoked periodically to provide opportunities for other threads to execute. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240327032022.78391-1-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
3124591f68 |
bpf: add bpf_modify_return_test_tp() kfunc triggering tracepoint
Add a simple bpf_modify_return_test_tp() kfunc, available to all program types, that is useful for various testing and benchmarking scenarios, as it allows to trigger most tracing BPF program types from BPF side, allowing to do complex testing and benchmarking scenarios. It is also attachable to for fmod_ret programs, making it a good and simple way to trigger fmod_ret program under test/benchmark. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240326162151.3981687-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Haiyue Wang
|
55fc888ded |
bpf,arena: Use helper sizeof_field in struct accessors
Use the well defined helper sizeof_field() to calculate the size of a struct member, instead of doing custom calculations. Signed-off-by: Haiyue Wang <haiyue.wang@intel.com> Link: https://lore.kernel.org/r/20240327065334.8140-1-haiyue.wang@intel.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Mykyta Yatsenko
|
786bf0e7e2 |
bpf: improve error message for unsupported helper
BPF verifier emits "unknown func" message when given BPF program type does not support BPF helper. This message may be confusing for users, as important context that helper is unknown only to current program type is not provided. This patch changes message to "program of this type cannot use helper " and aligns dependent code in libbpf and tests. Any suggestions on improving/changing this message are welcome. Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Quentin Monnet <qmo@kernel.org> Link: https://lore.kernel.org/r/20240325152210.377548-1-yatsenko@meta.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jakub Kicinski
|
5e47fbe5ce |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts, or adjacent changes. Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
Andrei Matei
|
ecc6a21018 |
bpf: Protect against int overflow for stack access size
This patch re-introduces protection against the size of access to stack memory being negative; the access size can appear negative as a result of overflowing its signed int representation. This should not actually happen, as there are other protections along the way, but we should protect against it anyway. One code path was missing such protections (fixed in the previous patch in the series), causing out-of-bounds array accesses in check_stack_range_initialized(). This patch causes the verification of a program with such a non-sensical access size to fail. This check used to exist in a more indirect way, but was inadvertendly removed in |
|
|
Andrei Matei
|
a8d89feba7 |
bpf: Check bloom filter map value size
This patch adds a missing check to bloom filter creating, rejecting values above KMALLOC_MAX_SIZE. This brings the bloom map in line with many other map types. The lack of this protection can cause kernel crashes for value sizes that overflow int's. Such a crash was caught by syzkaller. The next patch adds more guard-rails at a lower level. Signed-off-by: Andrei Matei <andreimatei1@gmail.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240327024245.318299-2-andreimatei1@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Hari Bathini
|
96b98a6552 |
bpf: fix warning for crash_kexec
With [1], crash dump specific code is moved out of CONFIG_KEXEC_CORE
and placed under CONFIG_CRASH_DUMP, where it is more appropriate.
And since CONFIG_KEXEC & !CONFIG_CRASH_DUMP build option is supported
with that, it led to the below warning:
"WARN: resolve_btfids: unresolved symbol crash_kexec"
Fix it by using the appropriate #ifdef.
[1] https://lore.kernel.org/all/20240124051254.67105-1-bhe@redhat.com/
Acked-by: Baoquan He <bhe@redhat.com>
Fixes:
|
|
|
Jakub Kicinski
|
2a702c2e57 |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZgHylwAKCRDbK58LschI gzmaAPwKhDFFSU/DU08k22muJxLIXVR7Xx04baJ9mPiFrqZyyAEA8RFNamC7wZIB AnfwwoDjfDTP60rlXFaEf8UT5PpA7Ao= =/KF6 -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-03-25 We've added 38 non-merge commits during the last 13 day(s) which contain a total of 50 files changed, 867 insertions(+), 274 deletions(-). The main changes are: 1) Add the ability to specify and retrieve BPF cookie also for raw tracepoint programs in order to ease migration from classic to raw tracepoints, from Andrii Nakryiko. 2) Allow the use of bpf_get_{ns_,}current_pid_tgid() helper for all program types and add additional BPF selftests, from Yonghong Song. 3) Several improvements to bpftool and its build, for example, enabling libbpf logs when loading pid_iter in debug mode, from Quentin Monnet. 4) Check the return code of all BPF-related set_memory_*() functions during load and bail out in case they fail, from Christophe Leroy. 5) Avoid a goto in regs_refine_cond_op() such that the verifier can be better integrated into Agni tool which doesn't support backedges yet, from Harishankar Vishwanathan. 6) Add a small BPF trie perf improvement by always inlining longest_prefix_match, from Jesper Dangaard Brouer. 7) Small BPF selftest refactor in bpf_tcp_ca.c to utilize start_server() helper instead of open-coding it, from Geliang Tang. 8) Improve test_tc_tunnel.sh BPF selftest to prevent client connect before the server bind, from Alessandro Carminati. 9) Fix BPF selftest benchmark for older glibc and use syscall(SYS_gettid) instead of gettid(), from Alan Maguire. 10) Implement a backward-compatible method for struct_ops types with additional fields which are not present in older kernels, from Kui-Feng Lee. 11) Add a small helper to check if an instruction is addr_space_cast from as(0) to as(1) and utilize it in x86-64 JIT, from Puranjay Mohan. 12) Small cleanup to remove unnecessary error check in bpf_struct_ops_map_update_elem, from Martin KaFai Lau. 13) Improvements to libbpf fd validity checks for BPF map/programs, from Mykyta Yatsenko. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (38 commits) selftests/bpf: Fix flaky test btf_map_in_map/lookup_update bpf: implement insn_is_cast_user() helper for JITs bpf: Avoid get_kernel_nofault() to fetch kprobe entry IP selftests/bpf: Use start_server in bpf_tcp_ca bpf: Sync uapi bpf.h to tools directory libbpf: Add new sec_def "sk_skb/verdict" selftests/bpf: Mark uprobe trigger functions with nocf_check attribute selftests/bpf: Use syscall(SYS_gettid) instead of gettid() wrapper in bench bpf-next: Avoid goto in regs_refine_cond_op() bpftool: Clean up HOST_CFLAGS, HOST_LDFLAGS for bootstrap bpftool selftests/bpf: scale benchmark counting by using per-CPU counters bpftool: Remove unnecessary source files from bootstrap version bpftool: Enable libbpf logs when loading pid_iter in debug mode selftests/bpf: add raw_tp/tp_btf BPF cookie subtests libbpf: add support for BPF cookie for raw_tp/tp_btf programs bpf: support BPF cookie in raw tracepoint (raw_tp, tp_btf) programs bpf: pass whole link instead of prog when triggering raw tracepoint bpf: flatten bpf_probe_register call chain selftests/bpf: Prevent client connect before server bind in test_tc_tunnel.sh selftests/bpf: Add a sk_msg prog bpf_get_ns_current_pid_tgid() test ... ==================== Link: https://lore.kernel.org/r/20240325233940.7154-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Paolo Abeni
|
37ccdf7f11 |
bpf-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZgHmTAAKCRDbK58LschI g1gWAP9HjAWE/Sy0B2t9opIiTqRzdMJLYs2B4OFeHRI6+qQg0gD6A4jsKEh/xmtG Hhjw+AElJRFZ3SUIT4mZlljzUHIYYAA= =T0lM -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf Daniel Borkmann says: ==================== pull-request: bpf 2024-03-25 The following pull-request contains BPF updates for your *net* tree. We've added 17 non-merge commits during the last 12 day(s) which contain a total of 19 files changed, 184 insertions(+), 61 deletions(-). The main changes are: 1) Fix an arm64 BPF JIT bug in BPF_LDX_MEMSX implementation's offset handling found via test_bpf module, from Puranjay Mohan. 2) Various fixups to the BPF arena code in particular in the BPF verifier and around BPF selftests to match latest corresponding LLVM implementation, from Puranjay Mohan and Alexei Starovoitov. 3) Fix xsk to not assume that metadata is always requested in TX completion, from Stanislav Fomichev. 4) Fix riscv BPF JIT's kfunc parameter incompatibility between BPF and the riscv ABI which requires sign-extension on int/uint, from Pu Lehui. 5) Fix s390x BPF JIT's bpf_plt pointer arithmetic which triggered a crash when testing struct_ops, from Ilya Leoshkevich. 6) Fix libbpf's arena mmap handling which had incorrect u64-to-pointer cast on 32-bit architectures, from Andrii Nakryiko. 7) Fix libbpf to define MFD_CLOEXEC when not available, from Arnaldo Carvalho de Melo. 8) Fix arm64 BPF JIT implementation for 32bit unconditional bswap which resulted in an incorrect swap as indicated by test_bpf, from Artem Savkov. 9) Fix BPF man page build script to use silent mode, from Hangbin Liu. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf: riscv, bpf: Fix kfunc parameters incompatibility between bpf and riscv abi bpf: verifier: reject addr_space_cast insn without arena selftests/bpf: verifier_arena: fix mmap address for arm64 bpf: verifier: fix addr_space_cast from as(1) to as(0) libbpf: Define MFD_CLOEXEC if not available arm64: bpf: fix 32bit unconditional bswap bpf, arm64: fix bug in BPF_LDX_MEMSX libbpf: fix u64-to-pointer cast on 32-bit arches s390/bpf: Fix bpf_plt pointer arithmetic xsk: Don't assume metadata is always requested in TX completion selftests/bpf: Add arena test case for 4Gbyte corner case selftests/bpf: Remove hard coded PAGE_SIZE macro. libbpf, selftests/bpf: Adjust libbpf, bpftool, selftests to match LLVM bpf: Clarify bpf_arena comments. MAINTAINERS: Update email address for Quentin Monnet scripts/bpf_doc: Use silent mode when exec make cmd bpf: Temporarily disable atomic operations in BPF arena ==================== Link: https://lore.kernel.org/r/20240325213520.26688-1-daniel@iogearbox.net Signed-off-by: Paolo Abeni <pabeni@redhat.com> |
|
|
Puranjay Mohan
|
122fdbd2a0 |
bpf: verifier: reject addr_space_cast insn without arena
The verifier allows using the addr_space_cast instruction in a program
that doesn't have an associated arena. This was caught in the form an
invalid memory access in do_misc_fixups() when while converting
addr_space_cast to a normal 32-bit mov, env->prog->aux->arena was
dereferenced to check for BPF_F_NO_USER_CONV flag.
Reject programs that include the addr_space_cast instruction but don't
have an associated arena.
root@rv-tester:~# ./reproducer
Unable to handle kernel access to user memory without uaccess routines at virtual address 0000000000000030
Oops [#1]
[<ffffffff8017eeaa>] do_misc_fixups+0x43c/0x1168
[<ffffffff801936d6>] bpf_check+0xda8/0x22b6
[<ffffffff80174b32>] bpf_prog_load+0x486/0x8dc
[<ffffffff80176566>] __sys_bpf+0xbd8/0x214e
[<ffffffff80177d14>] __riscv_sys_bpf+0x22/0x2a
[<ffffffff80d2493a>] do_trap_ecall_u+0x102/0x17c
[<ffffffff80d3048c>] ret_from_exception+0x0/0x64
Fixes:
|
|
|
Puranjay Mohan
|
f7f5d1808b |
bpf: verifier: fix addr_space_cast from as(1) to as(0)
The verifier currently converts addr_space_cast from as(1) to as(0) that
is: BPF_ALU64 | BPF_MOV | BPF_X with off=1 and imm=1
to
BPF_ALU | BPF_MOV | BPF_X with imm=1 (32-bit mov)
Because of this imm=1, the JITs that have bpf_jit_needs_zext() == true,
interpret the converted instruction as BPF_ZEXT_REG(DST) which is a
special form of mov32, used for doing explicit zero extension on dst.
These JITs will just zero extend the dst reg and will not move the src to
dst before the zext.
Fix do_misc_fixups() to set imm=0 when converting addr_space_cast to a
normal mov32.
The JITs that have bpf_jit_needs_zext() == true rely on the verifier to
emit zext instructions. Mark dst_reg as subreg when doing cast from
as(1) to as(0) so the verifier emits a zext instruction after the mov.
Fixes:
|
|
|
Harishankar Vishwanathan
|
4c2a26fc80 |
bpf-next: Avoid goto in regs_refine_cond_op()
In case of GE/GT/SGE/JST instructions, regs_refine_cond_op() reuses the logic that does analysis of LE/LT/SLE/SLT instructions. This commit avoids the use of a goto to perform the reuse. Signed-off-by: Harishankar Vishwanathan <harishankar.vishwanathan@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240321002955.808604-1-harishankar.vishwanathan@gmail.com |
|
Yan Zhai
|
00bf631224 |
bpf: report RCU QS in cpumap kthread
When there are heavy load, cpumap kernel threads can be busy polling
packets from redirect queues and block out RCU tasks from reaching
quiescent states. It is insufficient to just call cond_resched() in such
context. Periodically raise a consolidated RCU QS before cond_resched
fixes the problem.
Fixes:
|
|
|
Andrii Nakryiko
|
68ca5d4eeb |
bpf: support BPF cookie in raw tracepoint (raw_tp, tp_btf) programs
Wire up BPF cookie for raw tracepoint programs (both BTF and non-BTF aware variants). This brings them up to part w.r.t. BPF cookie usage with classic tracepoint and fentry/fexit programs. Acked-by: Stanislav Fomichev <sdf@google.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Message-ID: <20240319233852.1977493-4-andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
d4dfc5700e |
bpf: pass whole link instead of prog when triggering raw tracepoint
Instead of passing prog as an argument to bpf_trace_runX() helpers, that are called from tracepoint triggering calls, store BPF link itself (struct bpf_raw_tp_link for raw tracepoints). This will allow to pass extra information like BPF cookie into raw tracepoint registration. Instead of replacing `struct bpf_prog *prog = __data;` with corresponding `struct bpf_raw_tp_link *link = __data;` assignment in `__bpf_trace_##call` I just passed `__data` through into underlying bpf_trace_runX() call. This works well because we implicitly cast `void *`, and it also avoids naming clashes with arguments coming from tracepoint's "proto" list. We could have run into the same problem with "prog", we just happened to not have a tracepoint that has "prog" input argument. We are less lucky with "link", as there are tracepoints using "link" argument name already. So instead of trying to avoid naming conflicts, let's just remove intermediate local variable. It doesn't hurt readibility, it's either way a bit of a maze of calls and macros, that requires careful reading. Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Message-ID: <20240319233852.1977493-3-andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Yonghong Song
|
eb166e522c |
bpf: Allow helper bpf_get_[ns_]current_pid_tgid() for all prog types
Currently bpf_get_current_pid_tgid() is allowed in tracing, cgroup and sk_msg progs while bpf_get_ns_current_pid_tgid() is only allowed in tracing progs. We have an internal use case where for an application running in a container (with pid namespace), user wants to get the pid associated with the pid namespace in a cgroup bpf program. Currently, cgroup bpf progs already allow bpf_get_current_pid_tgid(). Let us allow bpf_get_ns_current_pid_tgid() as well. With auditing the code, bpf_get_current_pid_tgid() is also used by sk_msg prog. But there are no side effect to expose these two helpers to all prog types since they do not reveal any kernel specific data. The detailed discussion is in [1]. So with this patch, both bpf_get_current_pid_tgid() and bpf_get_ns_current_pid_tgid() are put in bpf_base_func_proto(), making them available to all program types. [1] https://lore.kernel.org/bpf/20240307232659.1115872-1-yonghong.song@linux.dev/ Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20240315184854.2975190-1-yonghong.song@linux.dev |
|
Jesper Dangaard Brouer
|
1a4a0cb798 |
bpf/lpm_trie: Inline longest_prefix_match for fastpath
The BPF map type LPM (Longest Prefix Match) is used heavily
in production by multiple products that have BPF components.
Perf data shows trie_lookup_elem() and longest_prefix_match()
being part of kernels perf top.
For every level in the LPM tree trie_lookup_elem() calls out
to longest_prefix_match(). The compiler is free to inline this
call, but chooses not to inline, because other slowpath callers
(that can be invoked via syscall) exists like trie_update_elem(),
trie_delete_elem() or trie_get_next_key().
bcc/tools/funccount -Ti 1 'trie_lookup_elem|longest_prefix_match.isra.0'
FUNC COUNT
trie_lookup_elem 664945
longest_prefix_match.isra.0 8101507
Observation on a single random machine shows a factor 12 between
the two functions. Given an average of 12 levels in the trie being
searched.
This patch force inlining longest_prefix_match(), but only for
the lookup fastpath to balance object instruction size.
In production with AMD CPUs, measuring the function latency of
'trie_lookup_elem' (bcc/tools/funclatency) we are seeing an improvement
function latency reduction 7-8% with this patch applied (to production
kernels 6.6 and 6.1). Analyzing perf data, we can explain this rather
large improvement due to reducing the overhead for AMD side-channel
mitigation SRSO (Speculative Return Stack Overflow).
Fixes:
|
|
Christophe Leroy
|
c733239f8f |
bpf: Check return from set_memory_rox()
arch_protect_bpf_trampoline() and alloc_new_pack() call set_memory_rox() which can fail, leading to unprotected memory. Take into account return from set_memory_rox() function and add __must_check flag to arch_protect_bpf_trampoline(). Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Reviewed-by: Kees Cook <keescook@chromium.org> Link: https://lore.kernel.org/r/fe1c163c83767fde5cab31d209a4a6be3ddb3a73.1710574353.git.christophe.leroy@csgroup.eu Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Christophe Leroy
|
e3362acd79 |
bpf: Remove arch_unprotect_bpf_trampoline()
Last user of arch_unprotect_bpf_trampoline() was removed by commit |
|
|
Martin KaFai Lau
|
7f3edd0c72 |
bpf: Remove unnecessary err < 0 check in bpf_struct_ops_map_update_elem
There is a "if (err)" check earlier, so the "if (err < 0)"
check that this patch removing is unnecessary. It was my overlook
when making adjustments to the bpf_struct_ops_prepare_trampoline()
such that the caller does not have to worry about the new page when
the function returns error.
Fixes:
|
|
|
Alexei Starovoitov
|
ee498a38f3 |
bpf: Clarify bpf_arena comments.
Clarify two bpf_arena comments, use existing SZ_4G #define, improve page_cnt check. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20240315021834.62988-2-alexei.starovoitov@gmail.com |
|
|
Christophe Leroy
|
7d2cc63eca |
bpf: Take return from set_memory_ro() into account with bpf_prog_lock_ro()
set_memory_ro() can fail, leaving memory unprotected. Check its return and take it into account as an error. Link: https://github.com/KSPP/linux/issues/7 Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: linux-hardening@vger.kernel.org <linux-hardening@vger.kernel.org> Reviewed-by: Kees Cook <keescook@chromium.org> Message-ID: <286def78955e04382b227cb3e4b6ba272a7442e3.1709850515.git.christophe.leroy@csgroup.eu> Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
4d8926a040 |
bpf: preserve sleepable bit in subprog info
Copy over main program's sleepable bit into subprog's info. This might be important for, e.g., freplace cases. Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Stanislav Fomichev <sdf@google.com> Message-ID: <20240314000127.3881569-1-andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Puranjay Mohan
|
44d79142ed |
bpf: Temporarily disable atomic operations in BPF arena
Currently, the x86 JIT handling PROBE_MEM32 tagged accesses is not
equipped to handle atomic accesses into PTR_TO_ARENA, as no PROBE_MEM32
tagging is performed and no handling is enabled for them.
This will lead to unsafety as the offset into arena will dereferenced
directly without turning it into a base + offset access into the arena
region.
Since the changes to the x86 JIT will be fairly involved, for now,
temporarily disallow use of PTR_TO_ARENA as the destination operand for
atomics until support is added to the JIT backend.
Fixes:
|
|
|
Jakub Kicinski
|
5f20e6ab1f |
for-netdev
-----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEE+soXsSLHKoYyzcli6rmadz2vbToFAmXvm7IACgkQ6rmadz2v bTqdMA//VMHNHVLb4oROoXyQD9fw2mCmIUEKzP88RXfqcxsfEX7HF+k8B5ZTk0ro CHXTAnc79+Qqg0j24bkQKxup/fKBQVw9D+Ia4b3ytlm1I2MtyU/16xNEzVhAPU2D iKk6mVBsEdCbt/GjpWORy/VVnZlZpC7BOpZLxsbbxgXOndnCegyjXzSnLGJGxdvi zkrQTn2SrFzLi6aNpVLqrv6Nks6HJusfCKsIrtlbkQ85dulasHOtwK9s6GF60nte aaho+MPx3L+lWEgapsm8rR779pHaYIB/GbZUgEPxE/xUJ/V8BzDgFNLMzEiIBRMN a0zZam11BkBzCfcO9gkvDRByaei/dZz2jdqfU4GlHklFj1WFfz8Q7fRLEPINksvj WXLgJADGY5mtGbjG21FScThxzj+Ruqwx0a13ddlyI/W+P3y5yzSWsLwJG5F9p0oU 6nlkJ4U8yg+9E1ie5ae0TibqvRJzXPjfOERZGwYDSVvfQGzv1z+DGSOPMmgNcWYM dIaO+A/+NS3zdbk8+1PP2SBbhHPk6kWyCUByWc7wMzCPTiwriFGY/DD2sN+Fsufo zorzfikUQOlTfzzD5jbmT49U8hUQUf6QIWsu7BijSiHaaC7am4S8QB2O6ibJMqdv yNiwvuX+ThgVIY3QKrLLqL0KPGeKMR5mtfq6rrwSpfp/b4g27FE= =eFgA -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Alexei Starovoitov says: ==================== pull-request: bpf-next 2024-03-11 We've added 59 non-merge commits during the last 9 day(s) which contain a total of 88 files changed, 4181 insertions(+), 590 deletions(-). The main changes are: 1) Enforce VM_IOREMAP flag and range in ioremap_page_range and introduce VM_SPARSE kind and vm_area_[un]map_pages to be used in bpf_arena, from Alexei. 2) Introduce bpf_arena which is sparse shared memory region between bpf program and user space where structures inside the arena can have pointers to other areas of the arena, and pointers work seamlessly for both user-space programs and bpf programs, from Alexei and Andrii. 3) Introduce may_goto instruction that is a contract between the verifier and the program. The verifier allows the program to loop assuming it's behaving well, but reserves the right to terminate it, from Alexei. 4) Use IETF format for field definitions in the BPF standard document, from Dave. 5) Extend struct_ops libbpf APIs to allow specify version suffixes for stuct_ops map types, share the same BPF program between several map definitions, and other improvements, from Eduard. 6) Enable struct_ops support for more than one page in trampolines, from Kui-Feng. 7) Support kCFI + BPF on riscv64, from Puranjay. 8) Use bpf_prog_pack for arm64 bpf trampoline, from Puranjay. 9) Fix roundup_pow_of_two undefined behavior on 32-bit archs, from Toke. ==================== Link: https://lore.kernel.org/r/20240312003646.8692-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Andrii Nakryiko
|
66c8473135 |
bpf: move sleepable flag from bpf_prog_aux to bpf_prog
prog->aux->sleepable is checked very frequently as part of (some) BPF program run hot paths. So this extra aux indirection seems wasteful and on busy systems might cause unnecessary memory cache misses. Let's move sleepable flag into prog itself to eliminate unnecessary pointer dereference. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Message-ID: <20240309004739.2961431-1-andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Puranjay Mohan
|
d6170e4aaf |
bpf: hardcode BPF_PROG_PACK_SIZE to 2MB * num_possible_nodes()
On some architectures like ARM64, PMD_SIZE can be really large in some
configurations. Like with CONFIG_ARM64_64K_PAGES=y the PMD_SIZE is
512MB.
Use 2MB * num_possible_nodes() as the size for allocations done through
the prog pack allocator. On most architectures, PMD_SIZE will be equal
to 2MB in case of 4KB pages and will be greater than 2MB for bigger page
sizes.
Fixes:
|
|
|
Alexei Starovoitov
|
2edc3de6fb |
bpf: Recognize btf_decl_tag("arg: Arena") as PTR_TO_ARENA.
In global bpf functions recognize btf_decl_tag("arg:arena") as PTR_TO_ARENA.
Note, when the verifier sees:
__weak void foo(struct bar *p)
it recognizes 'p' as PTR_TO_MEM and 'struct bar' has to be a struct with scalars.
Hence the only way to use arena pointers in global functions is to tag them with "arg:arena".
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/bpf/20240308010812.89848-7-alexei.starovoitov@gmail.com
|
|
|
Alexei Starovoitov
|
6082b6c328 |
bpf: Recognize addr_space_cast instruction in the verifier.
rY = addr_space_cast(rX, 0, 1) tells the verifier that rY->type = PTR_TO_ARENA.
Any further operations on PTR_TO_ARENA register have to be in 32-bit domain.
The verifier will mark load/store through PTR_TO_ARENA with PROBE_MEM32.
JIT will generate them as kern_vm_start + 32bit_addr memory accesses.
rY = addr_space_cast(rX, 1, 0) tells the verifier that rY->type = unknown scalar.
If arena->map_flags has BPF_F_NO_USER_CONV set then convert cast_user to mov32 as well.
Otherwise JIT will convert it to:
rY = (u32)rX;
if (rY)
rY |= arena->user_vm_start & ~(u64)~0U;
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240308010812.89848-6-alexei.starovoitov@gmail.com
|
|
|
Alexei Starovoitov
|
142fd4d2dc |
bpf: Add x86-64 JIT support for bpf_addr_space_cast instruction.
LLVM generates bpf_addr_space_cast instruction while translating pointers between native (zero) address space and __attribute__((address_space(N))). The addr_space=1 is reserved as bpf_arena address space. rY = addr_space_cast(rX, 0, 1) is processed by the verifier and converted to normal 32-bit move: wX = wY rY = addr_space_cast(rX, 1, 0) has to be converted by JIT: aux_reg = upper_32_bits of arena->user_vm_start aux_reg <<= 32 wX = wY // clear upper 32 bits of dst register if (wX) // if not zero add upper bits of user_vm_start wX |= aux_reg JIT can do it more efficiently: mov dst_reg32, src_reg32 // 32-bit move shl dst_reg, 32 or dst_reg, user_vm_start rol dst_reg, 32 xor r11, r11 test dst_reg32, dst_reg32 // check if lower 32-bit are zero cmove r11, dst_reg // if so, set dst_reg to zero // Intel swapped src/dst register encoding in CMOVcc Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20240308010812.89848-5-alexei.starovoitov@gmail.com |
|
|
Alexei Starovoitov
|
667a86ad9b |
bpf: Disasm support for addr_space_cast instruction.
LLVM generates rX = addr_space_cast(rY, dst_addr_space, src_addr_space) instruction when pointers in non-zero address space are used by the bpf program. Recognize this insn in uapi and in bpf disassembler. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/bpf/20240308010812.89848-3-alexei.starovoitov@gmail.com |
|
|
Alexei Starovoitov
|
317460317a |
bpf: Introduce bpf_arena.
Introduce bpf_arena, which is a sparse shared memory region between the bpf program and user space. Use cases: 1. User space mmap-s bpf_arena and uses it as a traditional mmap-ed anonymous region, like memcached or any key/value storage. The bpf program implements an in-kernel accelerator. XDP prog can search for a key in bpf_arena and return a value without going to user space. 2. The bpf program builds arbitrary data structures in bpf_arena (hash tables, rb-trees, sparse arrays), while user space consumes it. 3. bpf_arena is a "heap" of memory from the bpf program's point of view. The user space may mmap it, but bpf program will not convert pointers to user base at run-time to improve bpf program speed. Initially, the kernel vm_area and user vma are not populated. User space can fault in pages within the range. While servicing a page fault, bpf_arena logic will insert a new page into the kernel and user vmas. The bpf program can allocate pages from that region via bpf_arena_alloc_pages(). This kernel function will insert pages into the kernel vm_area. The subsequent fault-in from user space will populate that page into the user vma. The BPF_F_SEGV_ON_FAULT flag at arena creation time can be used to prevent fault-in from user space. In such a case, if a page is not allocated by the bpf program and not present in the kernel vm_area, the user process will segfault. This is useful for use cases 2 and 3 above. bpf_arena_alloc_pages() is similar to user space mmap(). It allocates pages either at a specific address within the arena or allocates a range with the maple tree. bpf_arena_free_pages() is analogous to munmap(), which frees pages and removes the range from the kernel vm_area and from user process vmas. bpf_arena can be used as a bpf program "heap" of up to 4GB. The speed of bpf program is more important than ease of sharing with user space. This is use case 3. In such a case, the BPF_F_NO_USER_CONV flag is recommended. It will tell the verifier to treat the rX = bpf_arena_cast_user(rY) instruction as a 32-bit move wX = wY, which will improve bpf prog performance. Otherwise, bpf_arena_cast_user is translated by JIT to conditionally add the upper 32 bits of user vm_start (if the pointer is not NULL) to arena pointers before they are stored into memory. This way, user space sees them as valid 64-bit pointers. Diff https://github.com/llvm/llvm-project/pull/84410 enables LLVM BPF backend generate the bpf_addr_space_cast() instruction to cast pointers between address_space(1) which is reserved for bpf_arena pointers and default address space zero. All arena pointers in a bpf program written in C language are tagged as __attribute__((address_space(1))). Hence, clang provides helpful diagnostics when pointers cross address space. Libbpf and the kernel support only address_space == 1. All other address space identifiers are reserved. rX = bpf_addr_space_cast(rY, /* dst_as */ 1, /* src_as */ 0) tells the verifier that rX->type = PTR_TO_ARENA. Any further operations on PTR_TO_ARENA register have to be in the 32-bit domain. The verifier will mark load/store through PTR_TO_ARENA with PROBE_MEM32. JIT will generate them as kern_vm_start + 32bit_addr memory accesses. The behavior is similar to copy_from_kernel_nofault() except that no address checks are necessary. The address is guaranteed to be in the 4GB range. If the page is not present, the destination register is zeroed on read, and the operation is ignored on write. rX = bpf_addr_space_cast(rY, 0, 1) tells the verifier that rX->type = unknown scalar. If arena->map_flags has BPF_F_NO_USER_CONV set, then the verifier converts such cast instructions to mov32. Otherwise, JIT will emit native code equivalent to: rX = (u32)rY; if (rY) rX |= clear_lo32_bits(arena->user_vm_start); /* replace hi32 bits in rX */ After such conversion, the pointer becomes a valid user pointer within bpf_arena range. The user process can access data structures created in bpf_arena without any additional computations. For example, a linked list built by a bpf program can be walked natively by user space. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Barret Rhoden <brho@google.com> Link: https://lore.kernel.org/bpf/20240308010812.89848-2-alexei.starovoitov@gmail.com |
|
Eric Dumazet
|
aa70d2d16f |
net: move skbuff_cache(s) to net_hotdata
skbuff_cache, skbuff_fclone_cache and skb_small_head_cache are used in rx/tx fast paths. Move them to net_hotdata for better cache locality. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240306160031.874438-11-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
Toke Høiland-Jørgensen
|
7a4b21250b |
bpf: Fix stackmap overflow check on 32-bit arches
The stackmap code relies on roundup_pow_of_two() to compute the number
of hash buckets, and contains an overflow check by checking if the
resulting value is 0. However, on 32-bit arches, the roundup code itself
can overflow by doing a 32-bit left-shift of an unsigned long value,
which is undefined behaviour, so it is not guaranteed to truncate
neatly. This was triggered by syzbot on the DEVMAP_HASH type, which
contains the same check, copied from the hashtab code.
The commit in the fixes tag actually attempted to fix this, but the fix
did not account for the UB, so the fix only works on CPUs where an
overflow does result in a neat truncation to zero, which is not
guaranteed. Checking the value before rounding does not have this
problem.
Fixes:
|
|
|
Toke Høiland-Jørgensen
|
6787d916c2 |
bpf: Fix hashtab overflow check on 32-bit arches
The hashtab code relies on roundup_pow_of_two() to compute the number of
hash buckets, and contains an overflow check by checking if the
resulting value is 0. However, on 32-bit arches, the roundup code itself
can overflow by doing a 32-bit left-shift of an unsigned long value,
which is undefined behaviour, so it is not guaranteed to truncate
neatly. This was triggered by syzbot on the DEVMAP_HASH type, which
contains the same check, copied from the hashtab code. So apply the same
fix to hashtab, by moving the overflow check to before the roundup.
Fixes:
|
|
|
Toke Høiland-Jørgensen
|
281d464a34 |
bpf: Fix DEVMAP_HASH overflow check on 32-bit arches
The devmap code allocates a number hash buckets equal to the next power
of two of the max_entries value provided when creating the map. When
rounding up to the next power of two, the 32-bit variable storing the
number of buckets can overflow, and the code checks for overflow by
checking if the truncated 32-bit value is equal to 0. However, on 32-bit
arches the rounding up itself can overflow mid-way through, because it
ends up doing a left-shift of 32 bits on an unsigned long value. If the
size of an unsigned long is four bytes, this is undefined behaviour, so
there is no guarantee that we'll end up with a nice and tidy 0-value at
the end.
Syzbot managed to turn this into a crash on arm32 by creating a
DEVMAP_HASH with max_entries > 0x80000000 and then trying to update it.
Fix this by moving the overflow check to before the rounding up
operation.
Fixes:
|
|
|
Alexei Starovoitov
|
fe5064158c |
bpf: Tell bpf programs kernel's PAGE_SIZE
vmlinux BTF includes all kernel enums. Add __PAGE_SIZE = PAGE_SIZE enum, so that bpf programs that include vmlinux.h can easily access it. Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20240307031228.42896-7-alexei.starovoitov@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Alexei Starovoitov
|
cf2c2e4a3d |
bpf: Plumb get_unmapped_area() callback into bpf_map_ops
Subsequent patches introduce bpf_arena that imposes special alignment requirements on address selection. Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20240307031228.42896-4-alexei.starovoitov@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Alexei Starovoitov
|
8d94f1357c |
bpf: Recognize '__map' suffix in kfunc arguments
Recognize 'void *p__map' kfunc argument as 'struct bpf_map *p__map'.
It allows kfunc to have 'void *' argument for maps, since bpf progs
will call them as:
struct {
__uint(type, BPF_MAP_TYPE_ARENA);
...
} arena SEC(".maps");
bpf_kfunc_with_map(... &arena ...);
Underneath libbpf will load CONST_PTR_TO_MAP into the register via ld_imm64
insn. If kfunc was defined with 'struct bpf_map *' it would pass the
verifier as well, but bpf prog would need to type cast the argument
(void *)&arena, which is not clean.
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/r/20240307031228.42896-3-alexei.starovoitov@gmail.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
|
|
|
Alexei Starovoitov
|
88d1d4a7ee |
bpf: Allow kfuncs return 'void *'
Recognize return of 'void *' from kfunc as returning unknown scalar. Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/r/20240307031228.42896-2-alexei.starovoitov@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Jakub Kicinski
|
e3afe5dd3a |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts. Adjacent changes: net/core/page_pool_user.c |
|
|
Eduard Zingerman
|
bd70a8fb7c |
bpf: Allow all printable characters in BTF DATASEC names
The intent is to allow libbpf to use SEC("?.struct_ops") to identify
struct_ops maps that are optional, e.g. like in the following BPF code:
SEC("?.struct_ops")
struct test_ops optional_map = { ... };
Which yields the following BTF:
...
[13] DATASEC '?.struct_ops' size=0 vlen=...
...
To load such BTF libbpf rewrites DATASEC name before load.
After this patch the rewrite won't be necessary.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240306104529.6453-15-eddyz87@gmail.com
|
|
|
Alexei Starovoitov
|
4f81c16f50 |
bpf: Recognize that two registers are safe when their ranges match
When open code iterators, bpf_loop or may_goto are used the following two states are equivalent and safe to prune the search: cur state: fp-8_w=scalar(id=3,smin=umin=smin32=umin32=2,smax=umax=smax32=umax32=11,var_off=(0x0; 0xf)) old state: fp-8_rw=scalar(id=2,smin=umin=smin32=umin32=1,smax=umax=smax32=umax32=11,var_off=(0x0; 0xf)) In other words "exact" state match should ignore liveness and precision marks, since open coded iterator logic didn't complete their propagation, reg_old->type == NOT_INIT && reg_cur->type != NOT_INIT is also not safe to prune while looping, but range_within logic that applies to scalars, ptr_to_mem, map_value, pkt_ptr is safe to rely on. Avoid doing such comparison when regular infinite loop detection logic is used, otherwise bounded loop logic will declare such "infinite loop" as false positive. Such example is in progs/verifier_loops1.c not_an_inifinite_loop(). Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Tested-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20240306031929.42666-3-alexei.starovoitov@gmail.com |
|
|
Alexei Starovoitov
|
011832b97b |
bpf: Introduce may_goto instruction
Introduce may_goto instruction that from the verifier pov is similar to
open coded iterators bpf_for()/bpf_repeat() and bpf_loop() helper, but it
doesn't iterate any objects.
In assembly 'may_goto' is a nop most of the time until bpf runtime has to
terminate the program for whatever reason. In the current implementation
may_goto has a hidden counter, but other mechanisms can be used.
For programs written in C the later patch introduces 'cond_break' macro
that combines 'may_goto' with 'break' statement and has similar semantics:
cond_break is a nop until bpf runtime has to break out of this loop.
It can be used in any normal "for" or "while" loop, like
for (i = zero; i < cnt; cond_break, i++) {
The verifier recognizes that may_goto is used in the program, reserves
additional 8 bytes of stack, initializes them in subprog prologue, and
replaces may_goto instruction with:
aux_reg = *(u64 *)(fp - 40)
if aux_reg == 0 goto pc+off
aux_reg -= 1
*(u64 *)(fp - 40) = aux_reg
may_goto instruction can be used by LLVM to implement __builtin_memcpy,
__builtin_strcmp.
may_goto is not a full substitute for bpf_for() macro.
bpf_for() doesn't have induction variable that verifiers sees,
so 'i' in bpf_for(i, 0, 100) is seen as imprecise and bounded.
But when the code is written as:
for (i = 0; i < 100; cond_break, i++)
the verifier see 'i' as precise constant zero,
hence cond_break (aka may_goto) doesn't help to converge the loop.
A static or global variable can be used as a workaround:
static int zero = 0;
for (i = zero; i < 100; cond_break, i++) // works!
may_goto works well with arena pointers that don't need to be bounds
checked on access. Load/store from arena returns imprecise unbounded
scalar and loops with may_goto pass the verifier.
Reserve new opcode BPF_JMP | BPF_JCOND for may_goto insn.
JCOND stands for conditional pseudo jump.
Since goto_or_nop insn was proposed, it may use the same opcode.
may_goto vs goto_or_nop can be distinguished by src_reg:
code = BPF_JMP | BPF_JCOND
src_reg = 0 - may_goto
src_reg = 1 - goto_or_nop
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Tested-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20240306031929.42666-2-alexei.starovoitov@gmail.com
|
|
|
Toke Høiland-Jørgensen
|
2487007aa3 |
cpumap: Zero-initialise xdp_rxq_info struct before running XDP program
When running an XDP program that is attached to a cpumap entry, we don't
initialise the xdp_rxq_info data structure being used in the xdp_buff
that backs the XDP program invocation. Tobias noticed that this leads to
random values being returned as the xdp_md->rx_queue_index value for XDP
programs running in a cpumap.
This means we're basically returning the contents of the uninitialised
memory, which is bad. Fix this by zero-initialising the rxq data
structure before running the XDP program.
Fixes:
|
|
|
Eduard Zingerman
|
e9a8e5a587 |
bpf: check bpf_func_state->callback_depth when pruning states
When comparing current and cached states verifier should consider
bpf_func_state->callback_depth. Current state cannot be pruned against
cached state, when current states has more iterations left compared to
cached state. Current state has more iterations left when it's
callback_depth is smaller.
Below is an example illustrating this bug, minimized from mailing list
discussion [0] (assume that BPF_F_TEST_STATE_FREQ is set).
The example is not a safe program: if loop_cb point (1) is followed by
loop_cb point (2), then division by zero is possible at point (4).
struct ctx {
__u64 a;
__u64 b;
__u64 c;
};
static void loop_cb(int i, struct ctx *ctx)
{
/* assume that generated code is "fallthrough-first":
* if ... == 1 goto
* if ... == 2 goto
* <default>
*/
switch (bpf_get_prandom_u32()) {
case 1: /* 1 */ ctx->a = 42; return 0; break;
case 2: /* 2 */ ctx->b = 42; return 0; break;
default: /* 3 */ ctx->c = 42; return 0; break;
}
}
SEC("tc")
__failure
__flag(BPF_F_TEST_STATE_FREQ)
int test(struct __sk_buff *skb)
{
struct ctx ctx = { 7, 7, 7 };
bpf_loop(2, loop_cb, &ctx, 0); /* 0 */
/* assume generated checks are in-order: .a first */
if (ctx.a == 42 && ctx.b == 42 && ctx.c == 7)
asm volatile("r0 /= 0;":::"r0"); /* 4 */
return 0;
}
Prior to this commit verifier built the following checkpoint tree for
this example:
.------------------------------------- Checkpoint / State name
| .-------------------------------- Code point number
| | .---------------------------- Stack state {ctx.a,ctx.b,ctx.c}
| | | .------------------- Callback depth in frame #0
v v v v
- (0) {7P,7P,7},depth=0
- (3) {7P,7P,7},depth=1
- (0) {7P,7P,42},depth=1
- (3) {7P,7,42},depth=2
- (0) {7P,7,42},depth=2 loop terminates because of depth limit
- (4) {7P,7,42},depth=0 predicted false, ctx.a marked precise
- (6) exit
(a) - (2) {7P,7,42},depth=2
- (0) {7P,42,42},depth=2 loop terminates because of depth limit
- (4) {7P,42,42},depth=0 predicted false, ctx.a marked precise
- (6) exit
(b) - (1) {7P,7P,42},depth=2
- (0) {42P,7P,42},depth=2 loop terminates because of depth limit
- (4) {42P,7P,42},depth=0 predicted false, ctx.{a,b} marked precise
- (6) exit
- (2) {7P,7,7},depth=1 considered safe, pruned using checkpoint (a)
(c) - (1) {7P,7P,7},depth=1 considered safe, pruned using checkpoint (b)
Here checkpoint (b) has callback_depth of 2, meaning that it would
never reach state {42,42,7}.
While checkpoint (c) has callback_depth of 1, and thus
could yet explore the state {42,42,7} if not pruned prematurely.
This commit makes forbids such premature pruning,
allowing verifier to explore states sub-tree starting at (c):
(c) - (1) {7,7,7P},depth=1
- (0) {42P,7,7P},depth=1
...
- (2) {42,7,7},depth=2
- (0) {42,42,7},depth=2 loop terminates because of depth limit
- (4) {42,42,7},depth=0 predicted true, ctx.{a,b,c} marked precise
- (5) division by zero
[0] https://lore.kernel.org/bpf/9b251840-7cb8-4d17-bd23-1fc8071d8eef@linux.dev/
Fixes:
|
|
|
Kui-Feng Lee
|
187e2af05a |
bpf: struct_ops supports more than one page for trampolines.
The BPF struct_ops previously only allowed one page of trampolines. Each function pointer of a struct_ops is implemented by a struct_ops bpf program. Each struct_ops bpf program requires a trampoline. The following selftest patch shows each page can hold a little more than 20 trampolines. While one page is more than enough for the tcp-cc usecase, the sched_ext use case shows that one page is not always enough and hits the one page limit. This patch overcomes the one page limit by allocating another page when needed and it is limited to a total of MAX_IMAGE_PAGES (8) pages which is more than enough for reasonable usages. The variable st_map->image has been changed to st_map->image_pages, and its type has been changed to an array of pointers to pages. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240224223418.526631-3-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
73e4f9e615 |
bpf, net: validate struct_ops when updating value.
Perform all validations when updating values of struct_ops maps. Doing validation in st_ops->reg() and st_ops->update() is not necessary anymore. However, tcp_register_congestion_control() has been called in various places. It still needs to do validations. Cc: netdev@vger.kernel.org Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240224223418.526631-2-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Eric Dumazet
|
80bfab79b8 |
net: adopt skb_network_offset() and similar helpers
This is a cleanup patch, making code a bit more concise.
1) Use skb_network_offset(skb) in place of
(skb_network_header(skb) - skb->data)
2) Use -skb_network_offset(skb) in place of
(skb->data - skb_network_header(skb))
3) Use skb_transport_offset(skb) in place of
(skb_transport_header(skb) - skb->data)
4) Use skb_inner_transport_offset(skb) in place of
(skb_inner_transport_header(skb) - skb->data)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Edward Cree <ecree.xilinx@gmail.com> # for sfc
Signed-off-by: David S. Miller <davem@davemloft.net>
|
|
|
Jakub Kicinski
|
4b2765ae41 |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZeEKVAAKCRDbK58LschI g7oYAQD5Jlv4fIVTvxvfZrTTZ2tU+OsPa75mc8SDKwpash3YygEA8kvESy8+t6pg D6QmSf1DIZdFoSp/bV+pfkNWMeR8gwg= =mTAj -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2024-02-29 We've added 119 non-merge commits during the last 32 day(s) which contain a total of 150 files changed, 3589 insertions(+), 995 deletions(-). The main changes are: 1) Extend the BPF verifier to enable static subprog calls in spin lock critical sections, from Kumar Kartikeya Dwivedi. 2) Fix confusing and incorrect inference of PTR_TO_CTX argument type in BPF global subprogs, from Andrii Nakryiko. 3) Larger batch of riscv BPF JIT improvements and enabling inlining of the bpf_kptr_xchg() for RV64, from Pu Lehui. 4) Allow skeleton users to change the values of the fields in struct_ops maps at runtime, from Kui-Feng Lee. 5) Extend the verifier's capabilities of tracking scalars when they are spilled to stack, especially when the spill or fill is narrowing, from Maxim Mikityanskiy & Eduard Zingerman. 6) Various BPF selftest improvements to fix errors under gcc BPF backend, from Jose E. Marchesi. 7) Avoid module loading failure when the module trying to register a struct_ops has its BTF section stripped, from Geliang Tang. 8) Annotate all kfuncs in .BTF_ids section which eventually allows for automatic kfunc prototype generation from bpftool, from Daniel Xu. 9) Several updates to the instruction-set.rst IETF standardization document, from Dave Thaler. 10) Shrink the size of struct bpf_map resp. bpf_array, from Alexei Starovoitov. 11) Initial small subset of BPF verifier prepwork for sleepable bpf_timer, from Benjamin Tissoires. 12) Fix bpftool to be more portable to musl libc by using POSIX's basename(), from Arnaldo Carvalho de Melo. 13) Add libbpf support to gcc in CORE macro definitions, from Cupertino Miranda. 14) Remove a duplicate type check in perf_event_bpf_event, from Florian Lehner. 15) Fix bpf_spin_{un,}lock BPF helpers to actually annotate them with notrace correctly, from Yonghong Song. 16) Replace the deprecated bpf_lpm_trie_key 0-length array with flexible array to fix build warnings, from Kees Cook. 17) Fix resolve_btfids cross-compilation to non host-native endianness, from Viktor Malik. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (119 commits) selftests/bpf: Test if shadow types work correctly. bpftool: Add an example for struct_ops map and shadow type. bpftool: Generated shadow variables for struct_ops maps. libbpf: Convert st_ops->data to shadow type. libbpf: Set btf_value_type_id of struct bpf_map for struct_ops. bpf: Replace bpf_lpm_trie_key 0-length array with flexible array bpf, arm64: use bpf_prog_pack for memory management arm64: patching: implement text_poke API bpf, arm64: support exceptions arm64: stacktrace: Implement arch_bpf_stack_walk() for the BPF JIT bpf: add is_async_callback_calling_insn() helper bpf: introduce in_sleepable() helper bpf: allow more maps in sleepable bpf programs selftests/bpf: Test case for lacking CFI stub functions. bpf: Check cfi_stubs before registering a struct_ops type. bpf: Clarify batch lookup/lookup_and_delete semantics bpf, docs: specify which BPF_ABS and BPF_IND fields were zero bpf, docs: Fix typos in instruction-set.rst selftests/bpf: update tcp_custom_syncookie to use scalar packet offset bpf: Shrink size of struct bpf_map/bpf_array. ... ==================== Link: https://lore.kernel.org/r/20240301001625.8800-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
Kees Cook
|
896880ff30 |
bpf: Replace bpf_lpm_trie_key 0-length array with flexible array
Replace deprecated 0-length array in struct bpf_lpm_trie_key with
flexible array. Found with GCC 13:
../kernel/bpf/lpm_trie.c:207:51: warning: array subscript i is outside array bounds of 'const __u8[0]' {aka 'const unsigned char[]'} [-Warray-bounds=]
207 | *(__be16 *)&key->data[i]);
| ^~~~~~~~~~~~~
../include/uapi/linux/swab.h:102:54: note: in definition of macro '__swab16'
102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x))
| ^
../include/linux/byteorder/generic.h:97:21: note: in expansion of macro '__be16_to_cpu'
97 | #define be16_to_cpu __be16_to_cpu
| ^~~~~~~~~~~~~
../kernel/bpf/lpm_trie.c:206:28: note: in expansion of macro 'be16_to_cpu'
206 | u16 diff = be16_to_cpu(*(__be16 *)&node->data[i]
^
| ^~~~~~~~~~~
In file included from ../include/linux/bpf.h:7:
../include/uapi/linux/bpf.h:82:17: note: while referencing 'data'
82 | __u8 data[0]; /* Arbitrary size */
| ^~~~
And found at run-time under CONFIG_FORTIFY_SOURCE:
UBSAN: array-index-out-of-bounds in kernel/bpf/lpm_trie.c:218:49
index 0 is out of range for type '__u8 [*]'
Changing struct bpf_lpm_trie_key is difficult since has been used by
userspace. For example, in Cilium:
struct egress_gw_policy_key {
struct bpf_lpm_trie_key lpm_key;
__u32 saddr;
__u32 daddr;
};
While direct references to the "data" member haven't been found, there
are static initializers what include the final member. For example,
the "{}" here:
struct egress_gw_policy_key in_key = {
.lpm_key = { 32 + 24, {} },
.saddr = CLIENT_IP,
.daddr = EXTERNAL_SVC_IP & 0Xffffff,
};
To avoid the build time and run time warnings seen with a 0-sized
trailing array for struct bpf_lpm_trie_key, introduce a new struct
that correctly uses a flexible array for the trailing bytes,
struct bpf_lpm_trie_key_u8. As part of this, include the "header"
portion (which is just the "prefixlen" member), so it can be used
by anything building a bpf_lpr_trie_key that has trailing members that
aren't a u8 flexible array (like the self-test[1]), which is named
struct bpf_lpm_trie_key_hdr.
Unfortunately, C++ refuses to parse the __struct_group() helper, so
it is not possible to define struct bpf_lpm_trie_key_hdr directly in
struct bpf_lpm_trie_key_u8, so we must open-code the union directly.
Adjust the kernel code to use struct bpf_lpm_trie_key_u8 through-out,
and for the selftest to use struct bpf_lpm_trie_key_hdr. Add a comment
to the UAPI header directing folks to the two new options.
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Closes: https://paste.debian.net/hidden/ca500597/
Link: https://lore.kernel.org/all/202206281009.4332AA33@keescook/ [1]
Link: https://lore.kernel.org/bpf/20240222155612.it.533-kees@kernel.org
|
|
|
Benjamin Tissoires
|
2ab256e932 |
bpf: add is_async_callback_calling_insn() helper
Currently we have a special case for BPF_FUNC_timer_set_callback, let's introduce a helper we can extend for the kfunc that will come in a later patch Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240221-hid-bpf-sleepable-v3-3-1fb378ca6301@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
dfe6625df4 |
bpf: introduce in_sleepable() helper
No code change, but it'll allow to have only one place to change everything when we add in_sleepable in cur_state. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240221-hid-bpf-sleepable-v3-2-1fb378ca6301@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Benjamin Tissoires
|
55bad79e33 |
bpf: allow more maps in sleepable bpf programs
These 2 maps types are required for HID-BPF when a user wants to do IO with a device from a sleepable tracing point. Allowing BPF_MAP_TYPE_QUEUE (and therefore BPF_MAP_TYPE_STACK) allows for a BPF program to prepare from an IRQ the list of HID commands to send back to the device and then these commands can be retrieved from the sleepable trace point. Signed-off-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/20240221-hid-bpf-sleepable-v3-1-1fb378ca6301@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jakub Kicinski
|
fecc51559a |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: net/ipv4/udp.c |
|
|
Kui-Feng Lee
|
3e0008336a |
bpf: Check cfi_stubs before registering a struct_ops type.
Recently, st_ops->cfi_stubs was introduced. However, the upcoming new struct_ops support (e.g. sched_ext) is not aware of this and does not provide its own cfi_stubs. The kernel ends up NULL dereferencing the st_ops->cfi_stubs. Considering struct_ops supports kernel module now, this NULL check is necessary. This patch is to reject struct_ops registration that does not provide a cfi_stubs. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240222021105.1180475-2-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Yafang Shao
|
5f2ae606cb |
bpf: Fix an issue due to uninitialized bpf_iter_task
Failure to initialize it->pos, coupled with the presence of an invalid
value in the flags variable, can lead to it->pos referencing an invalid
task, potentially resulting in a kernel panic. To mitigate this risk, it's
crucial to ensure proper initialization of it->pos to NULL.
Fixes:
|
|
|
Martin KaFai Lau
|
0281b919e1 |
bpf: Fix racing between bpf_timer_cancel_and_free and bpf_timer_cancel
The following race is possible between bpf_timer_cancel_and_free
and bpf_timer_cancel. It will lead a UAF on the timer->timer.
bpf_timer_cancel();
spin_lock();
t = timer->time;
spin_unlock();
bpf_timer_cancel_and_free();
spin_lock();
t = timer->timer;
timer->timer = NULL;
spin_unlock();
hrtimer_cancel(&t->timer);
kfree(t);
/* UAF on t */
hrtimer_cancel(&t->timer);
In bpf_timer_cancel_and_free, this patch frees the timer->timer
after a rcu grace period. This requires a rcu_head addition
to the "struct bpf_hrtimer". Another kfree(t) happens in bpf_timer_init,
this does not need a kfree_rcu because it is still under the
spin_lock and timer->timer has not been visible by others yet.
In bpf_timer_cancel, rcu_read_lock() is added because this helper
can be used in a non rcu critical section context (e.g. from
a sleepable bpf prog). Other timer->timer usages in helpers.c
have been audited, bpf_timer_cancel() is the only place where
timer->timer is used outside of the spin_lock.
Another solution considered is to mark a t->flag in bpf_timer_cancel
and clear it after hrtimer_cancel() is done. In bpf_timer_cancel_and_free,
it busy waits for the flag to be cleared before kfree(t). This patch
goes with a straight forward solution and frees timer->timer after
a rcu grace period.
Fixes:
|
|
|
Yonghong Song
|
682158ab53 |
bpf: Fix test verif_scale_strobemeta_subprogs failure due to llvm19
With latest llvm19, I hit the following selftest failures with $ ./test_progs -j libbpf: prog 'on_event': BPF program load failed: Permission denied libbpf: prog 'on_event': -- BEGIN PROG LOAD LOG -- combined stack size of 4 calls is 544. Too large verification time 1344153 usec stack depth 24+440+0+32 processed 51008 insns (limit 1000000) max_states_per_insn 19 total_states 1467 peak_states 303 mark_read 146 -- END PROG LOAD LOG -- libbpf: prog 'on_event': failed to load: -13 libbpf: failed to load object 'strobemeta_subprogs.bpf.o' scale_test:FAIL:expect_success unexpected error: -13 (errno 13) #498 verif_scale_strobemeta_subprogs:FAIL The verifier complains too big of the combined stack size (544 bytes) which exceeds the maximum stack limit 512. This is a regression from llvm19 ([1]). In the above error log, the original stack depth is 24+440+0+32. To satisfy interpreter's need, in verifier the stack depth is adjusted to 32+448+32+32=544 which exceeds 512, hence the error. The same adjusted stack size is also used for jit case. But the jitted codes could use smaller stack size. $ egrep -r stack_depth | grep round_up arm64/net/bpf_jit_comp.c: ctx->stack_size = round_up(prog->aux->stack_depth, 16); loongarch/net/bpf_jit.c: bpf_stack_adjust = round_up(ctx->prog->aux->stack_depth, 16); powerpc/net/bpf_jit_comp.c: cgctx.stack_size = round_up(fp->aux->stack_depth, 16); riscv/net/bpf_jit_comp32.c: round_up(ctx->prog->aux->stack_depth, STACK_ALIGN); riscv/net/bpf_jit_comp64.c: bpf_stack_adjust = round_up(ctx->prog->aux->stack_depth, 16); s390/net/bpf_jit_comp.c: u32 stack_depth = round_up(fp->aux->stack_depth, 8); sparc/net/bpf_jit_comp_64.c: stack_needed += round_up(stack_depth, 16); x86/net/bpf_jit_comp.c: EMIT3_off32(0x48, 0x81, 0xEC, round_up(stack_depth, 8)); x86/net/bpf_jit_comp.c: int tcc_off = -4 - round_up(stack_depth, 8); x86/net/bpf_jit_comp.c: round_up(stack_depth, 8)); x86/net/bpf_jit_comp.c: int tcc_off = -4 - round_up(stack_depth, 8); x86/net/bpf_jit_comp.c: EMIT3_off32(0x48, 0x81, 0xC4, round_up(stack_depth, 8)); In the above, STACK_ALIGN in riscv/net/bpf_jit_comp32.c is defined as 16. So stack is aligned in either 8 or 16, x86/s390 having 8-byte stack alignment and the rest having 16-byte alignment. This patch calculates total stack depth based on 16-byte alignment if jit is requested. For the above failing case, the new stack size will be 32+448+0+32=512 and no verification failure. llvm19 regression will be discussed separately in llvm upstream. The verifier change caused three test failures as these tests compared messages with stack size. More specifically, - test_global_funcs/global_func1: fail with interpreter mode and success with jit mode. Adjusted stack sizes so both jit and interpreter modes will fail. - async_stack_depth/{pseudo_call_check, async_call_root_check}: since jit and interpreter will calculate different stack sizes, the failure msg is adjusted to omit those specific stack size numbers. [1] https://lore.kernel.org/bpf/32bde0f0-1881-46c9-931a-673be566c61d@linux.dev/ Suggested-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240214232951.4113094-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
57354f5fde |
bpf: improve duplicate source code line detection
Verifier log avoids printing the same source code line multiple times
when a consecutive block of BPF assembly instructions are covered by the
same original (C) source code line. This greatly improves verifier log
legibility.
Unfortunately, this check is imperfect and in production applications it
quite often happens that verifier log will have multiple duplicated
source lines emitted, for no apparently good reason. E.g., this is
excerpt from a real-world BPF application (with register states omitted
for clarity):
BEFORE
======
; for (int i = 0; i < STROBE_MAX_MAP_ENTRIES; ++i) { @ strobemeta_probe.bpf.c:394
5369: (07) r8 += 2 ;
5370: (07) r7 += 16 ;
; for (int i = 0; i < STROBE_MAX_MAP_ENTRIES; ++i) { @ strobemeta_probe.bpf.c:394
5371: (07) r9 += 1 ;
5372: (79) r4 = *(u64 *)(r10 -32) ;
; for (int i = 0; i < STROBE_MAX_MAP_ENTRIES; ++i) { @ strobemeta_probe.bpf.c:394
5373: (55) if r9 != 0xf goto pc+2
; if (i >= map->cnt) @ strobemeta_probe.bpf.c:396
5376: (79) r1 = *(u64 *)(r10 -40) ;
5377: (79) r1 = *(u64 *)(r1 +8) ;
; if (i >= map->cnt) @ strobemeta_probe.bpf.c:396
5378: (dd) if r1 s<= r9 goto pc-5 ;
; descr->key_lens[i] = 0; @ strobemeta_probe.bpf.c:398
5379: (b4) w1 = 0 ;
5380: (6b) *(u16 *)(r8 -30) = r1 ;
; task, data, off, STROBE_MAX_STR_LEN, map->entries[i].key); @ strobemeta_probe.bpf.c:400
5381: (79) r3 = *(u64 *)(r7 -8) ;
5382: (7b) *(u64 *)(r10 -24) = r6 ;
; task, data, off, STROBE_MAX_STR_LEN, map->entries[i].key); @ strobemeta_probe.bpf.c:400
5383: (bc) w6 = w6 ;
; barrier_var(payload_off); @ strobemeta_probe.bpf.c:280
5384: (bf) r2 = r6 ;
5385: (bf) r1 = r4 ;
As can be seen, line 394 is emitted thrice, 396 is emitted twice, and
line 400 is duplicated as well. Note that there are no intermingling
other lines of source code in between these duplicates, so the issue is
not compiler reordering assembly instruction such that multiple original
source code lines are in effect.
It becomes more obvious what's going on if we look at *full* original line info
information (using btfdump for this, [0]):
#2764: line: insn #5363 --> 394:3 @ ./././strobemeta_probe.bpf.c
for (int i = 0; i < STROBE_MAX_MAP_ENTRIES; ++i) {
#2765: line: insn #5373 --> 394:21 @ ./././strobemeta_probe.bpf.c
for (int i = 0; i < STROBE_MAX_MAP_ENTRIES; ++i) {
#2766: line: insn #5375 --> 394:47 @ ./././strobemeta_probe.bpf.c
for (int i = 0; i < STROBE_MAX_MAP_ENTRIES; ++i) {
#2767: line: insn #5377 --> 394:3 @ ./././strobemeta_probe.bpf.c
for (int i = 0; i < STROBE_MAX_MAP_ENTRIES; ++i) {
#2768: line: insn #5378 --> 414:10 @ ./././strobemeta_probe.bpf.c
return off;
We can see that there are four line info records covering
instructions #5363 through #5377 (instruction indices are shifted due to
subprog instruction being appended to main program), all of them are
pointing to the same C source code line #394. But each of them points to
a different part of that line, which is denoted by differing column
numbers (3, 21, 47, 3).
But verifier log doesn't distinguish between parts of the same source code line
and doesn't emit this column number information, so for end user it's just a
repetitive visual noise. So let's improve the detection of repeated source code
line and avoid this.
With the changes in this patch, we get this output for the same piece of BPF
program log:
AFTER
=====
; for (int i = 0; i < STROBE_MAX_MAP_ENTRIES; ++i) { @ strobemeta_probe.bpf.c:394
5369: (07) r8 += 2 ;
5370: (07) r7 += 16 ;
5371: (07) r9 += 1 ;
5372: (79) r4 = *(u64 *)(r10 -32) ;
5373: (55) if r9 != 0xf goto pc+2
; if (i >= map->cnt) @ strobemeta_probe.bpf.c:396
5376: (79) r1 = *(u64 *)(r10 -40) ;
5377: (79) r1 = *(u64 *)(r1 +8) ;
5378: (dd) if r1 s<= r9 goto pc-5 ;
; descr->key_lens[i] = 0; @ strobemeta_probe.bpf.c:398
5379: (b4) w1 = 0 ;
5380: (6b) *(u16 *)(r8 -30) = r1 ;
; task, data, off, STROBE_MAX_STR_LEN, map->entries[i].key); @ strobemeta_probe.bpf.c:400
5381: (79) r3 = *(u64 *)(r7 -8) ;
5382: (7b) *(u64 *)(r10 -24) = r6 ;
5383: (bc) w6 = w6 ;
; barrier_var(payload_off); @ strobemeta_probe.bpf.c:280
5384: (bf) r2 = r6 ;
5385: (bf) r1 = r4 ;
All the duplication is gone and the log is cleaner and less distracting.
[0] https://github.com/anakryiko/btfdump
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240214174100.2847419-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
a4561f5afe |
bpf: Use O(log(N)) binary search to find line info record
Real-world BPF applications keep growing in size. Medium-sized production application can easily have 50K+ verified instructions, and its line info section in .BTF.ext has more than 3K entries. When verifier emits log with log_level>=1, it annotates assembly code with matched original C source code. Currently it uses linear search over line info records to find a match. As complexity of BPF applications grows, this O(K * N) approach scales poorly. So, let's instead of linear O(N) search for line info record use faster equivalent O(log(N)) binary search algorithm. It's not a plain binary search, as we don't look for exact match. It's an upper bound search variant, looking for rightmost line info record that starts at or before given insn_off. Some unscientific measurements were done before and after this change. They were done in VM and fluctuate a bit, but overall the speed up is undeniable. BASELINE ======== File Program Duration (us) Insns -------------------------------- ---------------- ------------- ------ katran.bpf.o balancer_ingress 2497130 343552 pyperf600.bpf.linked3.o on_event 12389611 627288 strobelight_pyperf_libbpf.o on_py_event 387399 52445 -------------------------------- ---------------- ------------- ------ BINARY SEARCH ============= File Program Duration (us) Insns -------------------------------- ---------------- ------------- ------ katran.bpf.o balancer_ingress 2339312 343552 pyperf600.bpf.linked3.o on_event 5602203 627288 strobelight_pyperf_libbpf.o on_py_event 294761 52445 -------------------------------- ---------------- ------------- ------ While Katran's speed up is pretty modest (about 105ms, or 6%), for production pyperf BPF program (on_py_event) it's much greater already, going from 387ms down to 295ms (23% improvement). Looking at BPF selftests's biggest pyperf example, we can see even more dramatic improvement, shaving more than 50% of time, going from 12.3s down to 5.6s. Different amount of improvement is the function of overall amount of BPF assembly instructions in .bpf.o files (which contributes to how much line info records there will be and thus, on average, how much time linear search will take), among other things: $ llvm-objdump -d katran.bpf.o | wc -l 3863 $ llvm-objdump -d strobelight_pyperf_libbpf.o | wc -l 6997 $ llvm-objdump -d pyperf600.bpf.linked3.o | wc -l 87854 Granted, this only applies to debugging cases (e.g., using veristat, or failing verification in production), but seems worth doing to improve overall developer experience anyways. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/20240214002311.2197116-1-andrii@kernel.org |
|
|
Andrii Nakryiko
|
7cc13adbd0 |
bpf: emit source code file name and line number in verifier log
As BPF applications grow in size and complexity and are separated into multiple .bpf.c files that are statically linked together, it becomes harder and harder to match verifier's BPF assembly level output to original C code. While often annotated C source code is unique enough to be able to identify the file it belongs to, quite often this is actually problematic as parts of source code can be quite generic. Long story short, it is very useful to see source code file name and line number information along with the original C code. Verifier already knows this information, we just need to output it. This patch extends verifier log with file name and line number information, emitted next to original (presumably C) source code, annotating BPF assembly output, like so: ; <original C code> @ <filename>.bpf.c:<line> If file name has directory names in it, they are stripped away. This should be fine in practice as file names tend to be pretty unique with C code anyways, and keeping log size smaller is always good. In practice this might look something like below, where some code is coming from application files, while others are from libbpf's usdt.bpf.h header file: ; if (STROBEMETA_READ( @ strobemeta_probe.bpf.c:534 5592: (79) r1 = *(u64 *)(r10 -56) ; R1_w=mem_or_null(id=1589,sz=7680) R10=fp0 5593: (7b) *(u64 *)(r10 -56) = r1 ; R1_w=mem_or_null(id=1589,sz=7680) R10=fp0 5594: (79) r3 = *(u64 *)(r10 -8) ; R3_w=scalar() R10=fp0 fp-8=mmmmmmmm ... 170: (71) r1 = *(u8 *)(r8 +15) ; frame1: R1_w=scalar(...) R8_w=map_value(map=__bpf_usdt_spec,ks=4,vs=208) 171: (67) r1 <<= 56 ; frame1: R1_w=scalar(...) 172: (c7) r1 s>>= 56 ; frame1: R1_w=scalar(smin=smin32=-128,smax=smax32=127) ; val <<= arg_spec->arg_bitshift; @ usdt.bpf.h:183 173: (67) r1 <<= 32 ; frame1: R1_w=scalar(...) 174: (77) r1 >>= 32 ; frame1: R1_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) 175: (79) r2 = *(u64 *)(r10 -8) ; frame1: R2_w=scalar() R10=fp0 fp-8=mmmmmmmm 176: (6f) r2 <<= r1 ; frame1: R1_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) R2_w=scalar() 177: (7b) *(u64 *)(r10 -8) = r2 ; frame1: R2_w=scalar(id=61) R10=fp0 fp-8_w=scalar(id=61) ; if (arg_spec->arg_signed) @ usdt.bpf.h:184 178: (bf) r3 = r2 ; frame1: R2_w=scalar(id=61) R3_w=scalar(id=61) 179: (7f) r3 >>= r1 ; frame1: R1_w=scalar(smin=0,smax=umax=0xffffffff,var_off=(0x0; 0xffffffff)) R3_w=scalar() ; if (arg_spec->arg_signed) @ usdt.bpf.h:184 180: (71) r4 = *(u8 *)(r8 +14) 181: safe log_fixup tests needed a minor adjustment as verifier log output increased a bit and that test is quite sensitive to such changes. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240212235944.2816107-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
879bbe7aa4 |
bpf: don't infer PTR_TO_CTX for programs with unnamed context type
For program types that don't have named context type name (e.g., BPF
iterator programs or tracepoint programs), ctx_tname will be a non-NULL
empty string. For such programs it shouldn't be possible to have
PTR_TO_CTX argument for global subprogs based on type name alone.
arg:ctx tag is the only way to have PTR_TO_CTX passed into global
subprog for such program types.
Fix this loophole, which currently would assume PTR_TO_CTX whenever
user uses a pointer to anonymous struct as an argument to their global
subprogs. This happens in practice with the following (quite common, in
practice) approach:
typedef struct { /* anonymous */
int x;
} my_type_t;
int my_subprog(my_type_t *arg) { ... }
User's intent is to have PTR_TO_MEM argument for `arg`, but verifier
will complain about expecting PTR_TO_CTX.
This fix also closes unintended s390x-specific KPROBE handling of
PTR_TO_CTX case. Selftest change is necessary to accommodate this.
Fixes:
|
|
|
Andrii Nakryiko
|
824c58fb10 |
bpf: handle bpf_user_pt_regs_t typedef explicitly for PTR_TO_CTX global arg
Expected canonical argument type for global function arguments
representing PTR_TO_CTX is `bpf_user_pt_regs_t *ctx`. This currently
works on s390x by accident because kernel resolves such typedef to
underlying struct (which is anonymous on s390x), and erroneously
accepting it as expected context type. We are fixing this problem next,
which would break s390x arch, so we need to handle `bpf_user_pt_regs_t`
case explicitly for KPROBE programs.
Fixes:
|
|
|
Andrii Nakryiko
|
fb5b86cfd4 |
bpf: simplify btf_get_prog_ctx_type() into btf_is_prog_ctx_type()
Return result of btf_get_prog_ctx_type() is never used and callers only check NULL vs non-NULL case to determine if given type matches expected PTR_TO_CTX type. So rename function to `btf_is_prog_ctx_type()` and return a simple true/false. We'll use this simpler interface to handle kprobe program type's special typedef case in the next patch. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240212233221.2575350-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Oliver Crumrine
|
32e18e7688 |
bpf: remove check in __cgroup_bpf_run_filter_skb
Originally, this patch removed a redundant check in BPF_CGROUP_RUN_PROG_INET_EGRESS, as the check was already being done in the function it called, __cgroup_bpf_run_filter_skb. For v2, it was reccomended that I remove the check from __cgroup_bpf_run_filter_skb, and add the checks to the other macro that calls that function, BPF_CGROUP_RUN_PROG_INET_INGRESS. To sum it up, checking that the socket exists and that it is a full socket is now part of both macros BPF_CGROUP_RUN_PROG_INET_EGRESS and BPF_CGROUP_RUN_PROG_INET_INGRESS, and it is no longer part of the function they call, __cgroup_bpf_run_filter_skb. v3->v4: Fixed weird merge conflict. v2->v3: Sent to bpf-next instead of generic patch v1->v2: Addressed feedback about where check should be removed. Signed-off-by: Oliver Crumrine <ozlinuxc@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/7lv62yiyvmj5a7eozv2iznglpkydkdfancgmbhiptrgvgan5sy@3fl3onchgdz3 Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
1611603537 |
bpf: Create argument information for nullable arguments.
Collect argument information from the type information of stub functions to mark arguments of BPF struct_ops programs with PTR_MAYBE_NULL if they are nullable. A nullable argument is annotated by suffixing "__nullable" at the argument name of stub function. For nullable arguments, this patch sets a struct bpf_ctx_arg_aux to label their reg_type with PTR_TO_BTF_ID | PTR_TRUSTED | PTR_MAYBE_NULL. This makes the verifier to check programs and ensure that they properly check the pointer. The programs should check if the pointer is null before accessing the pointed memory. The implementer of a struct_ops type should annotate the arguments that can be null. The implementer should define a stub function (empty) as a placeholder for each defined operator. The name of a stub function should be in the pattern "<st_op_type>__<operator name>". For example, for test_maybe_null of struct bpf_testmod_ops, it's stub function name should be "bpf_testmod_ops__test_maybe_null". You mark an argument nullable by suffixing the argument name with "__nullable" at the stub function. Since we already has stub functions for kCFI, we just reuse these stub functions with the naming convention mentioned earlier. These stub functions with the naming convention is only required if there are nullable arguments to annotate. For functions having not nullable arguments, stub functions are not necessary for the purpose of this patch. This patch will prepare a list of struct bpf_ctx_arg_aux, aka arg_info, for each member field of a struct_ops type. "arg_info" will be assigned to "prog->aux->ctx_arg_info" of BPF struct_ops programs in check_struct_ops_btf_id() so that it can be used by btf_ctx_access() later to set reg_type properly for the verifier. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240209023750.1153905-4-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
6115a0aeef |
bpf: Move __kfunc_param_match_suffix() to btf.c.
Move __kfunc_param_match_suffix() to btf.c and rename it as btf_param_match_suffix(). It can be reused by bpf_struct_ops later. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240209023750.1153905-3-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
77c0208e19 |
bpf: add btf pointer to struct bpf_ctx_arg_aux.
Enable the providers to use types defined in a module instead of in the kernel (btf_vmlinux). Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240209023750.1153905-2-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Hari Bathini
|
11f522256e |
bpf: Fix warning for bpf_cpumask in verifier
Compiling with CONFIG_BPF_SYSCALL & !CONFIG_BPF_JIT throws the below warning: "WARN: resolve_btfids: unresolved symbol bpf_cpumask" Fix it by adding the appropriate #ifdef. Signed-off-by: Hari Bathini <hbathini@linux.ibm.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Stanislav Fomichev <sdf@google.com> Acked-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/bpf/20240208100115.602172-1-hbathini@linux.ibm.com |
|
|
Yonghong Song
|
178c54666f |
bpf: Mark bpf_spin_{lock,unlock}() helpers with notrace correctly
Currently tracing is supposed not to allow for bpf_spin_{lock,unlock}()
helper calls. This is to prevent deadlock for the following cases:
- there is a prog (prog-A) calling bpf_spin_{lock,unlock}().
- there is a tracing program (prog-B), e.g., fentry, attached
to bpf_spin_lock() and/or bpf_spin_unlock().
- prog-B calls bpf_spin_{lock,unlock}().
For such a case, when prog-A calls bpf_spin_{lock,unlock}(),
a deadlock will happen.
The related source codes are below in kernel/bpf/helpers.c:
notrace BPF_CALL_1(bpf_spin_lock, struct bpf_spin_lock *, lock)
notrace BPF_CALL_1(bpf_spin_unlock, struct bpf_spin_lock *, lock)
notrace is supposed to prevent fentry prog from attaching to
bpf_spin_{lock,unlock}().
But actually this is not the case and fentry prog can successfully
attached to bpf_spin_lock(). Siddharth Chintamaneni reported
the issue in [1]. The following is the macro definition for
above BPF_CALL_1:
#define BPF_CALL_x(x, name, ...) \
static __always_inline \
u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
typedef u64 (*btf_##name)(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__)); \
u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)); \
u64 name(__BPF_REG(x, __BPF_DECL_REGS, __BPF_N, __VA_ARGS__)) \
{ \
return ((btf_##name)____##name)(__BPF_MAP(x,__BPF_CAST,__BPF_N,__VA_ARGS__));\
} \
static __always_inline \
u64 ____##name(__BPF_MAP(x, __BPF_DECL_ARGS, __BPF_V, __VA_ARGS__))
#define BPF_CALL_1(name, ...) BPF_CALL_x(1, name, __VA_ARGS__)
The notrace attribute is actually applied to the static always_inline function
____bpf_spin_{lock,unlock}(). The actual callback function
bpf_spin_{lock,unlock}() is not marked with notrace, hence
allowing fentry prog to attach to two helpers, and this
may cause the above mentioned deadlock. Siddharth Chintamaneni
actually has a reproducer in [2].
To fix the issue, a new macro NOTRACE_BPF_CALL_1 is introduced which
will add notrace attribute to the original function instead of
the hidden always_inline function and this fixed the problem.
[1] https://lore.kernel.org/bpf/CAE5sdEigPnoGrzN8WU7Tx-h-iFuMZgW06qp0KHWtpvoXxf1OAQ@mail.gmail.com/
[2] https://lore.kernel.org/bpf/CAE5sdEg6yUc_Jz50AnUXEEUh6O73yQ1Z6NV2srJnef0ZrQkZew@mail.gmail.com/
Fixes:
|
|
|
Daniel Xu
|
5b268d1ebc |
bpf: Have bpf_rdonly_cast() take a const pointer
Since
|
|
Marco Elver
|
68bc61c26c |
bpf: Allow compiler to inline most of bpf_local_storage_lookup()
In various performance profiles of kernels with BPF programs attached,
bpf_local_storage_lookup() appears as a significant portion of CPU
cycles spent. To enable the compiler generate more optimal code, turn
bpf_local_storage_lookup() into a static inline function, where only the
cache insertion code path is outlined
Notably, outlining cache insertion helps avoid bloating callers by
duplicating setting up calls to raw_spin_{lock,unlock}_irqsave() (on
architectures which do not inline spin_lock/unlock, such as x86), which
would cause the compiler produce worse code by deciding to outline
otherwise inlinable functions. The call overhead is neutral, because we
make 2 calls either way: either calling raw_spin_lock_irqsave() and
raw_spin_unlock_irqsave(); or call __bpf_local_storage_insert_cache(),
which calls raw_spin_lock_irqsave(), followed by a tail-call to
raw_spin_unlock_irqsave() where the compiler can perform TCO and (in
optimized uninstrumented builds) turns it into a plain jump. The call to
__bpf_local_storage_insert_cache() can be elided entirely if
cacheit_lockit is a false constant expression.
Based on results from './benchs/run_bench_local_storage.sh' (21 trials,
reboot between each trial; x86 defconfig + BPF, clang 16) this produces
improvements in throughput and latency in the majority of cases, with an
average (geomean) improvement of 8%:
+---- Hashmap Control --------------------
|
| + num keys: 10
| : <before> | <after>
| +-+ hashmap (control) sequential get +----------------------+----------------------
| +- hits throughput | 14.789 M ops/s | 14.745 M ops/s ( ~ )
| +- hits latency | 67.679 ns/op | 67.879 ns/op ( ~ )
| +- important_hits throughput | 14.789 M ops/s | 14.745 M ops/s ( ~ )
|
| + num keys: 1000
| : <before> | <after>
| +-+ hashmap (control) sequential get +----------------------+----------------------
| +- hits throughput | 12.233 M ops/s | 12.170 M ops/s ( ~ )
| +- hits latency | 81.754 ns/op | 82.185 ns/op ( ~ )
| +- important_hits throughput | 12.233 M ops/s | 12.170 M ops/s ( ~ )
|
| + num keys: 10000
| : <before> | <after>
| +-+ hashmap (control) sequential get +----------------------+----------------------
| +- hits throughput | 7.220 M ops/s | 7.204 M ops/s ( ~ )
| +- hits latency | 138.522 ns/op | 138.842 ns/op ( ~ )
| +- important_hits throughput | 7.220 M ops/s | 7.204 M ops/s ( ~ )
|
| + num keys: 100000
| : <before> | <after>
| +-+ hashmap (control) sequential get +----------------------+----------------------
| +- hits throughput | 5.061 M ops/s | 5.165 M ops/s (+2.1%)
| +- hits latency | 198.483 ns/op | 194.270 ns/op (-2.1%)
| +- important_hits throughput | 5.061 M ops/s | 5.165 M ops/s (+2.1%)
|
| + num keys: 4194304
| : <before> | <after>
| +-+ hashmap (control) sequential get +----------------------+----------------------
| +- hits throughput | 2.864 M ops/s | 2.882 M ops/s ( ~ )
| +- hits latency | 365.220 ns/op | 361.418 ns/op (-1.0%)
| +- important_hits throughput | 2.864 M ops/s | 2.882 M ops/s ( ~ )
|
+---- Local Storage ----------------------
|
| + num_maps: 1
| : <before> | <after>
| +-+ local_storage cache sequential get +----------------------+----------------------
| +- hits throughput | 33.005 M ops/s | 39.068 M ops/s (+18.4%)
| +- hits latency | 30.300 ns/op | 25.598 ns/op (-15.5%)
| +- important_hits throughput | 33.005 M ops/s | 39.068 M ops/s (+18.4%)
| :
| : <before> | <after>
| +-+ local_storage cache interleaved get +----------------------+----------------------
| +- hits throughput | 37.151 M ops/s | 44.926 M ops/s (+20.9%)
| +- hits latency | 26.919 ns/op | 22.259 ns/op (-17.3%)
| +- important_hits throughput | 37.151 M ops/s | 44.926 M ops/s (+20.9%)
|
| + num_maps: 10
| : <before> | <after>
| +-+ local_storage cache sequential get +----------------------+----------------------
| +- hits throughput | 32.288 M ops/s | 38.099 M ops/s (+18.0%)
| +- hits latency | 30.972 ns/op | 26.248 ns/op (-15.3%)
| +- important_hits throughput | 3.229 M ops/s | 3.810 M ops/s (+18.0%)
| :
| : <before> | <after>
| +-+ local_storage cache interleaved get +----------------------+----------------------
| +- hits throughput | 34.473 M ops/s | 41.145 M ops/s (+19.4%)
| +- hits latency | 29.010 ns/op | 24.307 ns/op (-16.2%)
| +- important_hits throughput | 12.312 M ops/s | 14.695 M ops/s (+19.4%)
|
| + num_maps: 16
| : <before> | <after>
| +-+ local_storage cache sequential get +----------------------+----------------------
| +- hits throughput | 32.524 M ops/s | 38.341 M ops/s (+17.9%)
| +- hits latency | 30.748 ns/op | 26.083 ns/op (-15.2%)
| +- important_hits throughput | 2.033 M ops/s | 2.396 M ops/s (+17.9%)
| :
| : <before> | <after>
| +-+ local_storage cache interleaved get +----------------------+----------------------
| +- hits throughput | 34.575 M ops/s | 41.338 M ops/s (+19.6%)
| +- hits latency | 28.925 ns/op | 24.193 ns/op (-16.4%)
| +- important_hits throughput | 11.001 M ops/s | 13.153 M ops/s (+19.6%)
|
| + num_maps: 17
| : <before> | <after>
| +-+ local_storage cache sequential get +----------------------+----------------------
| +- hits throughput | 28.861 M ops/s | 32.756 M ops/s (+13.5%)
| +- hits latency | 34.649 ns/op | 30.530 ns/op (-11.9%)
| +- important_hits throughput | 1.700 M ops/s | 1.929 M ops/s (+13.5%)
| :
| : <before> | <after>
| +-+ local_storage cache interleaved get +----------------------+----------------------
| +- hits throughput | 31.529 M ops/s | 36.110 M ops/s (+14.5%)
| +- hits latency | 31.719 ns/op | 27.697 ns/op (-12.7%)
| +- important_hits throughput | 9.598 M ops/s | 10.993 M ops/s (+14.5%)
|
| + num_maps: 24
| : <before> | <after>
| +-+ local_storage cache sequential get +----------------------+----------------------
| +- hits throughput | 18.602 M ops/s | 19.937 M ops/s (+7.2%)
| +- hits latency | 53.767 ns/op | 50.166 ns/op (-6.7%)
| +- important_hits throughput | 0.776 M ops/s | 0.831 M ops/s (+7.2%)
| :
| : <before> | <after>
| +-+ local_storage cache interleaved get +----------------------+----------------------
| +- hits throughput | 21.718 M ops/s | 23.332 M ops/s (+7.4%)
| +- hits latency | 46.047 ns/op | 42.865 ns/op (-6.9%)
| +- important_hits throughput | 6.110 M ops/s | 6.564 M ops/s (+7.4%)
|
| + num_maps: 32
| : <before> | <after>
| +-+ local_storage cache sequential get +----------------------+----------------------
| +- hits throughput | 14.118 M ops/s | 14.626 M ops/s (+3.6%)
| +- hits latency | 70.856 ns/op | 68.381 ns/op (-3.5%)
| +- important_hits throughput | 0.442 M ops/s | 0.458 M ops/s (+3.6%)
| :
| : <before> | <after>
| +-+ local_storage cache interleaved get +----------------------+----------------------
| +- hits throughput | 17.111 M ops/s | 17.906 M ops/s (+4.6%)
| +- hits latency | 58.451 ns/op | 55.865 ns/op (-4.4%)
| +- important_hits throughput | 4.776 M ops/s | 4.998 M ops/s (+4.6%)
|
| + num_maps: 100
| : <before> | <after>
| +-+ local_storage cache sequential get +----------------------+----------------------
| +- hits throughput | 5.281 M ops/s | 5.528 M ops/s (+4.7%)
| +- hits latency | 192.398 ns/op | 183.059 ns/op (-4.9%)
| +- important_hits throughput | 0.053 M ops/s | 0.055 M ops/s (+4.9%)
| :
| : <before> | <after>
| +-+ local_storage cache interleaved get +----------------------+----------------------
| +- hits throughput | 6.265 M ops/s | 6.498 M ops/s (+3.7%)
| +- hits latency | 161.436 ns/op | 152.877 ns/op (-5.3%)
| +- important_hits throughput | 1.636 M ops/s | 1.697 M ops/s (+3.7%)
|
| + num_maps: 1000
| : <before> | <after>
| +-+ local_storage cache sequential get +----------------------+----------------------
| +- hits throughput | 0.355 M ops/s | 0.354 M ops/s ( ~ )
| +- hits latency | 2826.538 ns/op | 2827.139 ns/op ( ~ )
| +- important_hits throughput | 0.000 M ops/s | 0.000 M ops/s ( ~ )
| :
| : <before> | <after>
| +-+ local_storage cache interleaved get +----------------------+----------------------
| +- hits throughput | 0.404 M ops/s | 0.403 M ops/s ( ~ )
| +- hits latency | 2481.190 ns/op | 2487.555 ns/op ( ~ )
| +- important_hits throughput | 0.102 M ops/s | 0.101 M ops/s ( ~ )
The on_lookup test in {cgrp,task}_ls_recursion.c is removed
because the bpf_local_storage_lookup is no longer traceable
and adding tracepoint will make the compiler generate worse
code: https://lore.kernel.org/bpf/ZcJmok64Xqv6l4ZS@elver.google.com/
Signed-off-by: Marco Elver <elver@google.com>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240207122626.3508658-1-elver@google.com
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
|
|
Geliang Tang
|
947e56f82f |
bpf, btf: Check btf for register_bpf_struct_ops
Similar to the handling in the functions __register_btf_kfunc_id_set() and register_btf_id_dtor_kfuncs(), this patch uses the newly added helper check_btf_kconfigs() to handle module with its btf section stripped. While at it, the patch also adds the missed IS_ERR() check to fix the commit |
|
|
Geliang Tang
|
9e60b0e025 |
bpf, btf: Add check_btf_kconfigs helper
This patch extracts duplicate code on error path when btf_get_module_btf() returns NULL from the functions __register_btf_kfunc_id_set() and register_btf_id_dtor_kfuncs() into a new helper named check_btf_kconfigs() to check CONFIG_DEBUG_INFO_BTF and CONFIG_DEBUG_INFO_BTF_MODULES in it. Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/fa5537fc55f1e4d0bfd686598c81b7ab9dbd82b7.1707373307.git.tanggeliang@kylinos.cn Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Geliang Tang
|
b9a395f0f7 |
bpf, btf: Fix return value of register_btf_id_dtor_kfuncs
The same as __register_btf_kfunc_id_set(), to let the modules with stripped btf section loaded, this patch changes the return value of register_btf_id_dtor_kfuncs() too from -ENOENT to 0 when btf is NULL. Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn> Link: https://lore.kernel.org/r/eab65586d7fb0e72f2707d3747c7d4a5d60c823f.1707373307.git.tanggeliang@kylinos.cn Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
Masahiro Yamada
|
e55dad12ab |
bpf: Merge two CONFIG_BPF entries
'config BPF' exists in both init/Kconfig and kernel/bpf/Kconfig.
Commit
|
|
|
Kumar Kartikeya Dwivedi
|
6fceea0fa5 |
bpf: Transfer RCU lock state between subprog calls
Allow transferring an imbalanced RCU lock state between subprog calls during verification. This allows patterns where a subprog call returns with an RCU lock held, or a subprog call releases an RCU lock held by the caller. Currently, the verifier would end up complaining if the RCU lock is not released when processing an exit from a subprog, which is non-ideal if its execution is supposed to be enclosed in an RCU read section of the caller. Instead, simply only check whether we are processing exit for frame#0 and do not complain on an active RCU lock otherwise. We only need to update the check when processing BPF_EXIT insn, as copy_verifier_state is already set up to do the right thing. Suggested-by: David Vernet <void@manifault.com> Tested-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Acked-by: David Vernet <void@manifault.com> Link: https://lore.kernel.org/r/20240205055646.1112186-2-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Kumar Kartikeya Dwivedi
|
a44b1334aa |
bpf: Allow calling static subprogs while holding a bpf_spin_lock
Currently, calling any helpers, kfuncs, or subprogs except the graph data structure (lists, rbtrees) API kfuncs while holding a bpf_spin_lock is not allowed. One of the original motivations of this decision was to force the BPF programmer's hand into keeping the bpf_spin_lock critical section small, and to ensure the execution time of the program does not increase due to lock waiting times. In addition to this, some of the helpers and kfuncs may be unsafe to call while holding a bpf_spin_lock. However, when it comes to subprog calls, atleast for static subprogs, the verifier is able to explore their instructions during verification. Therefore, it is similar in effect to having the same code inlined into the critical section. Hence, not allowing static subprog calls in the bpf_spin_lock critical section is mostly an annoyance that needs to be worked around, without providing any tangible benefit. Unlike static subprog calls, global subprog calls are not safe to permit within the critical section, as the verifier does not explore them during verification, therefore whether the same lock will be taken again, or unlocked, cannot be ascertained. Therefore, allow calling static subprogs within a bpf_spin_lock critical section, and only reject it in case the subprog linkage is global. Acked-by: Yonghong Song <yonghong.song@linux.dev> Acked-by: David Vernet <void@manifault.com> Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20240204222349.938118-2-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Kui-Feng Lee
|
df9705eaa0 |
bpf: Remove an unnecessary check.
The "i" here is always equal to "btf_type_vlen(t)" since the "for_each_member()" loop never breaks. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240203055119.2235598-1-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Andrii Nakryiko
|
1eb986746a |
bpf: don't emit warnings intended for global subprogs for static subprogs
When btf_prepare_func_args() was generalized to handle both static and
global subprogs, a few warnings/errors that are meant only for global
subprog cases started to be emitted for static subprogs, where they are
sort of expected and irrelavant.
Stop polutting verifier logs with irrelevant scary-looking messages.
Fixes:
|
|
|
Andrii Nakryiko
|
8f13c34087 |
bpf: handle trusted PTR_TO_BTF_ID_OR_NULL in argument check logic
Add PTR_TRUSTED | PTR_MAYBE_NULL modifiers for PTR_TO_BTF_ID to
check_reg_type() to support passing trusted nullable PTR_TO_BTF_ID
registers into global functions accepting `__arg_trusted __arg_nullable`
arguments. This hasn't been caught earlier because tests were either
passing known non-NULL PTR_TO_BTF_ID registers or known NULL (SCALAR)
registers.
When utilizing this functionality in complicated real-world BPF
application that passes around PTR_TO_BTF_ID_OR_NULL, it became apparent
that verifier rejects valid case because check_reg_type() doesn't handle
this case explicitly. Existing check_reg_type() logic is already
anticipating this combination, so we just need to explicitly list this
combo in the switch statement.
Fixes:
|
|
|
Eduard Zingerman
|
6efbde200b |
bpf: Handle scalar spill vs all MISC in stacksafe()
When check_stack_read_fixed_off() reads value from an spi
all stack slots of which are set to STACK_{MISC,INVALID},
the destination register is set to unbound SCALAR_VALUE.
Exploit this fact by allowing stacksafe() to use a fake
unbound scalar register to compare 'mmmm mmmm' stack value
in old state vs spilled 64-bit scalar in current state
and vice versa.
Veristat results after this patch show some gains:
./veristat -C -e file,prog,states -f 'states_pct>10' not-opt after
File Program States (DIFF)
----------------------- --------------------- ---------------
bpf_overlay.o tail_rev_nodeport_lb4 -45 (-15.85%)
bpf_xdp.o tail_lb_ipv4 -541 (-19.57%)
pyperf100.bpf.o on_event -680 (-10.42%)
pyperf180.bpf.o on_event -2164 (-19.62%)
pyperf600.bpf.o on_event -9799 (-24.84%)
strobemeta.bpf.o on_event -9157 (-65.28%)
xdp_synproxy_kern.bpf.o syncookie_tc -54 (-19.29%)
xdp_synproxy_kern.bpf.o syncookie_xdp -74 (-24.50%)
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240127175237.526726-6-maxtram95@gmail.com
|
|
Maxim Mikityanskiy
|
c1e6148cb4 |
bpf: Preserve boundaries and track scalars on narrowing fill
When the width of a fill is smaller than the width of the preceding spill, the information about scalar boundaries can still be preserved, as long as it's coerced to the right width (done by coerce_reg_to_size). Even further, if the actual value fits into the fill width, the ID can be preserved as well for further tracking of equal scalars. Implement the above improvements, which makes narrowing fills behave the same as narrowing spills and MOVs between registers. Two tests are adjusted to accommodate for endianness differences and to take into account that it's now allowed to do a narrowing fill from the least significant bits. reg_bounds_sync is added to coerce_reg_to_size to correctly adjust umin/umax boundaries after the var_off truncation, for example, a 64-bit value 0xXXXXXXXX00000000, when read as a 32-bit, gets umin = 0, umax = 0xFFFFFFFF, var_off = (0x0; 0xffffffff00000000), which needs to be synced down to umax = 0, otherwise reg_bounds_sanity_check doesn't pass. Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240127175237.526726-4-maxtram95@gmail.com |
|
|
Maxim Mikityanskiy
|
e67ddd9b1c |
bpf: Track spilled unbounded scalars
Support the pattern where an unbounded scalar is spilled to the stack, then boundary checks are performed on the src register, after which the stack frame slot is refilled into a register. Before this commit, the verifier didn't treat the src register and the stack slot as related if the src register was an unbounded scalar. The register state wasn't copied, the id wasn't preserved, and the stack slot was marked as STACK_MISC. Subsequent boundary checks on the src register wouldn't result in updating the boundaries of the spilled variable on the stack. After this commit, the verifier will preserve the bond between src and dst even if src is unbounded, which permits to do boundary checks on src and refill dst later, still remembering its boundaries. Such a pattern is sometimes generated by clang when compiling complex long functions. One test is adjusted to reflect that now unbounded scalars are tracked. Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20240127175237.526726-2-maxtram95@gmail.com |
|
|
Matt Bobrowski
|
1581e5118e |
bpf: Minor clean-up to sleepable_lsm_hooks BTF set
There's already one main CONFIG_SECURITY_NETWORK ifdef block within the sleepable_lsm_hooks BTF set. Consolidate this duplicated ifdef block as there's no need for it and all things guarded by it should remain in one place in this specific context. Signed-off-by: Matt Bobrowski <mattbobrowski@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/Zbt1smz43GDMbVU3@google.com |
|
|
Daniel Xu
|
6f3189f38a |
bpf: treewide: Annotate BPF kfuncs in BTF
This commit marks kfuncs as such inside the .BTF_ids section. The upshot of these annotations is that we'll be able to automatically generate kfunc prototypes for downstream users. The process is as follows: 1. In source, use BTF_KFUNCS_START/END macro pair to mark kfuncs 2. During build, pahole injects into BTF a "bpf_kfunc" BTF_DECL_TAG for each function inside BTF_KFUNCS sets 3. At runtime, vmlinux or module BTF is made available in sysfs 4. At runtime, bpftool (or similar) can look at provided BTF and generate appropriate prototypes for functions with "bpf_kfunc" tag To ensure future kfunc are similarly tagged, we now also return error inside kfunc registration for untagged kfuncs. For vmlinux kfuncs, we also WARN(), as initcall machinery does not handle errors. Signed-off-by: Daniel Xu <dxu@dxuuu.xyz> Acked-by: Benjamin Tissoires <bentiss@kernel.org> Link: https://lore.kernel.org/r/e55150ceecbf0a5d961e608941165c0bee7bc943.1706491398.git.dxu@dxuuu.xyz Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
8f2b44cd9d |
bpf: add arg:nullable tag to be combined with trusted pointers
Add ability to mark arg:trusted arguments with optional arg:nullable tag to mark it as PTR_TO_BTF_ID_OR_NULL variant, which will allow callers to pass NULL, and subsequently will force global subprog's code to do NULL check. This allows to have "optional" PTR_TO_BTF_ID values passed into global subprogs. For now arg:nullable cannot be combined with anything else. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240130000648.2144827-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
e2b3c4ff5d |
bpf: add __arg_trusted global func arg tag
Add support for passing PTR_TO_BTF_ID registers to global subprogs. Currently only PTR_TRUSTED flavor of PTR_TO_BTF_ID is supported. Non-NULL semantics is assumed, so caller will be forced to prove PTR_TO_BTF_ID can't be NULL. Note, we disallow global subprogs to destroy passed in PTR_TO_BTF_ID arguments, even the trusted one. We achieve that by not setting ref_obj_id when validating subprog code. This basically enforces (in Rust terms) borrowing semantics vs move semantics. Borrowing semantics seems to be a better fit for isolated global subprog validation approach. Implementation-wise, we utilize existing logic for matching user-provided BTF type to kernel-side BTF type, used by BPF CO-RE logic and following same matching rules. We enforce a unique match for types. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240130000648.2144827-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Haiyue Wang
|
6668e818f9 |
bpf,token: Use BIT_ULL() to convert the bit mask
Replace the '(1ULL << *)' with the macro BIT_ULL(nr). Signed-off-by: Haiyue Wang <haiyue.wang@intel.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20240127134901.3698613-1-haiyue.wang@intel.com |
|
|
Andrii Nakryiko
|
add9c58cd4 |
bpf: move arg:ctx type enforcement check inside the main logic loop
Now that bpf and bpf-next trees converged and we don't run the risk of merge conflicts, move btf_validate_prog_ctx_type() into its most logical place inside the main logic loop. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240125205510.3642094-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Kui-Feng Lee
|
e6be8cd5d3 |
bpf: Fix error checks against bpf_get_btf_vmlinux().
In bpf_struct_ops_map_alloc, it needs to check for NULL in the returned
pointer of bpf_get_btf_vmlinux() when CONFIG_DEBUG_INFO_BTF is not set.
ENOTSUPP is used to preserve the same behavior before the
struct_ops kmod support.
In the function check_struct_ops_btf_id(), instead of redoing the
bpf_get_btf_vmlinux() that has already been done in syscall.c, the fix
here is to check for prog->aux->attach_btf_id.
BPF_PROG_TYPE_STRUCT_OPS must require attach_btf_id and syscall.c
guarantees a valid attach_btf as long as attach_btf_id is set.
When attach_btf_id is not set, this patch returns -ENOTSUPP
because it is what the selftest in test_libbpf_probe_prog_types()
and libbpf_probes.c are expecting for feature probing purpose.
Changes from v1:
- Remove an unnecessary NULL check in check_struct_ops_btf_id()
Reported-by: syzbot+88f0aafe5f950d7489d7@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/00000000000040d68a060fc8db8c@google.com/
Reported-by: syzbot+1336f3d4b10bcda75b89@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/00000000000026353b060fc21c07@google.com/
Fixes:
|
|
|
Andrii Nakryiko
|
6c1752e0b6 |
bpf: Support symbolic BPF FS delegation mount options
Besides already supported special "any" value and hex bit mask, support
string-based parsing of delegation masks based on exact enumerator
names. Utilize BTF information of `enum bpf_cmd`, `enum bpf_map_type`,
`enum bpf_prog_type`, and `enum bpf_attach_type` types to find supported
symbolic names (ignoring __MAX_xxx guard values and stripping repetitive
prefixes like BPF_ for cmd and attach types, BPF_MAP_TYPE_ for maps, and
BPF_PROG_TYPE_ for prog types). The case doesn't matter, but it is
normalized to lower case in mount option output. So "PROG_LOAD",
"prog_load", and "MAP_create" are all valid values to specify for
delegate_cmds options, "array" is among supported for map types, etc.
Besides supporting string values, we also support multiple values
specified at the same time, using colon (':') separator.
There are corresponding changes on bpf_show_options side to use known
values to print them in human-readable format, falling back to hex mask
printing, if there are any unrecognized bits. This shouldn't be
necessary when enum BTF information is present, but in general we should
always be able to fall back to this even if kernel was built without BTF.
As mentioned, emitted symbolic names are normalized to be all lower case.
Example below shows various ways to specify delegate_cmds options
through mount command and how mount options are printed back:
12/14 14:39:07.604
vmuser@archvm:~/local/linux/tools/testing/selftests/bpf
$ mount | rg token
$ sudo mkdir -p /sys/fs/bpf/token
$ sudo mount -t bpf bpffs /sys/fs/bpf/token \
-o delegate_cmds=prog_load:MAP_CREATE \
-o delegate_progs=kprobe \
-o delegate_attachs=xdp
$ mount | grep token
bpffs on /sys/fs/bpf/token type bpf (rw,relatime,delegate_cmds=map_create:prog_load,delegate_progs=kprobe,delegate_attachs=xdp)
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20240124022127.2379740-20-andrii@kernel.org
|
|
|
Andrii Nakryiko
|
aeaa97b006 |
bpf: Fail BPF_TOKEN_CREATE if no delegation option was set on BPF FS
It's quite confusing in practice when it's possible to successfully create a BPF token from BPF FS that didn't have any of delegate_xxx mount options set up. While it's not wrong, it's actually more meaningful to reject BPF_TOKEN_CREATE with specific error code (-ENOENT) to let user-space know that no token delegation is setup up. So, instead of creating empty BPF token that will be always ignored because it doesn't have any of the allow_xxx bits set, reject it with -ENOENT. If we ever need empty BPF token to be possible, we can support that with extra flag passed into BPF_TOKEN_CREATE. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20240124022127.2379740-19-andrii@kernel.org |
|
|
Andrii Nakryiko
|
f568a3d49a |
bpf,lsm: Add BPF token LSM hooks
Wire up bpf_token_create and bpf_token_free LSM hooks, which allow to allocate LSM security blob (we add `void *security` field to struct bpf_token for that), but also control who can instantiate BPF token. This follows existing pattern for BPF map and BPF prog. Also add security_bpf_token_allow_cmd() and security_bpf_token_capable() LSM hooks that allow LSM implementation to control and negate (if necessary) BPF token's delegation of a specific bpf_cmd and capability, respectively. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Paul Moore <paul@paul-moore.com> Link: https://lore.kernel.org/bpf/20240124022127.2379740-12-andrii@kernel.org |
|
|
Andrii Nakryiko
|
a2431c7eab |
bpf,lsm: Refactor bpf_map_alloc/bpf_map_free LSM hooks
Similarly to bpf_prog_alloc LSM hook, rename and extend bpf_map_alloc hook into bpf_map_create, taking not just struct bpf_map, but also bpf_attr and bpf_token, to give a fuller context to LSMs. Unlike bpf_prog_alloc, there is no need to move the hook around, as it currently is firing right before allocating BPF map ID and FD, which seems to be a sweet spot. But like bpf_prog_alloc/bpf_prog_free combo, make sure that bpf_map_free LSM hook is called even if bpf_map_create hook returned error, as if few LSMs are combined together it could be that one LSM successfully allocated security blob for its needs, while subsequent LSM rejected BPF map creation. The former LSM would still need to free up LSM blob, so we need to ensure security_bpf_map_free() is called regardless of the outcome. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Paul Moore <paul@paul-moore.com> Link: https://lore.kernel.org/bpf/20240124022127.2379740-11-andrii@kernel.org |
|
|
Andrii Nakryiko
|
1b67772e4e |
bpf,lsm: Refactor bpf_prog_alloc/bpf_prog_free LSM hooks
Based on upstream discussion ([0]), rework existing
bpf_prog_alloc_security LSM hook. Rename it to bpf_prog_load and instead
of passing bpf_prog_aux, pass proper bpf_prog pointer for a full BPF
program struct. Also, we pass bpf_attr union with all the user-provided
arguments for BPF_PROG_LOAD command. This will give LSMs as much
information as we can basically provide.
The hook is also BPF token-aware now, and optional bpf_token struct is
passed as a third argument. bpf_prog_load LSM hook is called after
a bunch of sanity checks were performed, bpf_prog and bpf_prog_aux were
allocated and filled out, but right before performing full-fledged BPF
verification step.
bpf_prog_free LSM hook is now accepting struct bpf_prog argument, for
consistency. SELinux code is adjusted to all new names, types, and
signatures.
Note, given that bpf_prog_load (previously bpf_prog_alloc) hook can be
used by some LSMs to allocate extra security blob, but also by other
LSMs to reject BPF program loading, we need to make sure that
bpf_prog_free LSM hook is called after bpf_prog_load/bpf_prog_alloc one
*even* if the hook itself returned error. If we don't do that, we run
the risk of leaking memory. This seems to be possible today when
combining SELinux and BPF LSM, as one example, depending on their
relative ordering.
Also, for BPF LSM setup, add bpf_prog_load and bpf_prog_free to
sleepable LSM hooks list, as they are both executed in sleepable
context. Also drop bpf_prog_load hook from untrusted, as there is no
issue with refcount or anything else anymore, that originally forced us
to add it to untrusted list in
|
|
|
Andrii Nakryiko
|
d79a354975 |
bpf: Consistently use BPF token throughout BPF verifier logic
Remove remaining direct queries to perfmon_capable() and bpf_capable() in BPF verifier logic and instead use BPF token (if available) to make decisions about privileges. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-9-andrii@kernel.org |
|
|
Andrii Nakryiko
|
bbc1d24724 |
bpf: Take into account BPF token when fetching helper protos
Instead of performing unconditional system-wide bpf_capable() and perfmon_capable() calls inside bpf_base_func_proto() function (and other similar ones) to determine eligibility of a given BPF helper for a given program, use previously recorded BPF token during BPF_PROG_LOAD command handling to inform the decision. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-8-andrii@kernel.org |
|
|
Andrii Nakryiko
|
caf8f28e03 |
bpf: Add BPF token support to BPF_PROG_LOAD command
Add basic support of BPF token to BPF_PROG_LOAD. BPF_F_TOKEN_FD flag should be set in prog_flags field when providing prog_token_fd. Wire through a set of allowed BPF program types and attach types, derived from BPF FS at BPF token creation time. Then make sure we perform bpf_token_capable() checks everywhere where it's relevant. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-7-andrii@kernel.org |
|
|
Andrii Nakryiko
|
9ea7c4bf17 |
bpf: Add BPF token support to BPF_BTF_LOAD command
Accept BPF token FD in BPF_BTF_LOAD command to allow BTF data loading through delegated BPF token. BPF_F_TOKEN_FD flag has to be specified when passing BPF token FD. Given BPF_BTF_LOAD command didn't have flags field before, we also add btf_flags field. BTF loading is a pretty straightforward operation, so as long as BPF token is created with allow_cmds granting BPF_BTF_LOAD command, kernel proceeds to parsing BTF data and creating BTF object. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-6-andrii@kernel.org |
|
|
Andrii Nakryiko
|
a177fc2bf6 |
bpf: Add BPF token support to BPF_MAP_CREATE command
Allow providing token_fd for BPF_MAP_CREATE command to allow controlled BPF map creation from unprivileged process through delegated BPF token. New BPF_F_TOKEN_FD flag is added to specify together with BPF token FD for BPF_MAP_CREATE command. Wire through a set of allowed BPF map types to BPF token, derived from BPF FS at BPF token creation time. This, in combination with allowed_cmds allows to create a narrowly-focused BPF token (controlled by privileged agent) with a restrictive set of BPF maps that application can attempt to create. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20240124022127.2379740-5-andrii@kernel.org |
|
|
Andrii Nakryiko
|
35f96de041 |
bpf: Introduce BPF token object
Add new kind of BPF kernel object, BPF token. BPF token is meant to
allow delegating privileged BPF functionality, like loading a BPF
program or creating a BPF map, from privileged process to a *trusted*
unprivileged process, all while having a good amount of control over which
privileged operations could be performed using provided BPF token.
This is achieved through mounting BPF FS instance with extra delegation
mount options, which determine what operations are delegatable, and also
constraining it to the owning user namespace (as mentioned in the
previous patch).
BPF token itself is just a derivative from BPF FS and can be created
through a new bpf() syscall command, BPF_TOKEN_CREATE, which accepts BPF
FS FD, which can be attained through open() API by opening BPF FS mount
point. Currently, BPF token "inherits" delegated command, map types,
prog type, and attach type bit sets from BPF FS as is. In the future,
having an BPF token as a separate object with its own FD, we can allow
to further restrict BPF token's allowable set of things either at the
creation time or after the fact, allowing the process to guard itself
further from unintentionally trying to load undesired kind of BPF
programs. But for now we keep things simple and just copy bit sets as is.
When BPF token is created from BPF FS mount, we take reference to the
BPF super block's owning user namespace, and then use that namespace for
checking all the {CAP_BPF, CAP_PERFMON, CAP_NET_ADMIN, CAP_SYS_ADMIN}
capabilities that are normally only checked against init userns (using
capable()), but now we check them using ns_capable() instead (if BPF
token is provided). See bpf_token_capable() for details.
Such setup means that BPF token in itself is not sufficient to grant BPF
functionality. User namespaced process has to *also* have necessary
combination of capabilities inside that user namespace. So while
previously CAP_BPF was useless when granted within user namespace, now
it gains a meaning and allows container managers and sys admins to have
a flexible control over which processes can and need to use BPF
functionality within the user namespace (i.e., container in practice).
And BPF FS delegation mount options and derived BPF tokens serve as
a per-container "flag" to grant overall ability to use bpf() (plus further
restrict on which parts of bpf() syscalls are treated as namespaced).
Note also, BPF_TOKEN_CREATE command itself requires ns_capable(CAP_BPF)
within the BPF FS owning user namespace, rounding up the ns_capable()
story of BPF token. Also creating BPF token in init user namespace is
currently not supported, given BPF token doesn't have any effect in init
user namespace anyways.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/bpf/20240124022127.2379740-4-andrii@kernel.org
|
|
|
Andrii Nakryiko
|
6fe01d3cbb |
bpf: Add BPF token delegation mount options to BPF FS
Add few new mount options to BPF FS that allow to specify that a given
BPF FS instance allows creation of BPF token (added in the next patch),
and what sort of operations are allowed under BPF token. As such, we get
4 new mount options, each is a bit mask
- `delegate_cmds` allow to specify which bpf() syscall commands are
allowed with BPF token derived from this BPF FS instance;
- if BPF_MAP_CREATE command is allowed, `delegate_maps` specifies
a set of allowable BPF map types that could be created with BPF token;
- if BPF_PROG_LOAD command is allowed, `delegate_progs` specifies
a set of allowable BPF program types that could be loaded with BPF token;
- if BPF_PROG_LOAD command is allowed, `delegate_attachs` specifies
a set of allowable BPF program attach types that could be loaded with
BPF token; delegate_progs and delegate_attachs are meant to be used
together, as full BPF program type is, in general, determined
through both program type and program attach type.
Currently, these mount options accept the following forms of values:
- a special value "any", that enables all possible values of a given
bit set;
- numeric value (decimal or hexadecimal, determined by kernel
automatically) that specifies a bit mask value directly;
- all the values for a given mount option are combined, if specified
multiple times. E.g., `mount -t bpf nodev /path/to/mount -o
delegate_maps=0x1 -o delegate_maps=0x2` will result in a combined 0x3
mask.
Ideally, more convenient (for humans) symbolic form derived from
corresponding UAPI enums would be accepted (e.g., `-o
delegate_progs=kprobe|tracepoint`) and I intend to implement this, but
it requires a bunch of UAPI header churn, so I postponed it until this
feature lands upstream or at least there is a definite consensus that
this feature is acceptable and is going to make it, just to minimize
amount of wasted effort and not increase amount of non-essential code to
be reviewed.
Attentive reader will notice that BPF FS is now marked as
FS_USERNS_MOUNT, which theoretically makes it mountable inside non-init
user namespace as long as the process has sufficient *namespaced*
capabilities within that user namespace. But in reality we still
restrict BPF FS to be mountable only by processes with CAP_SYS_ADMIN *in
init userns* (extra check in bpf_fill_super()). FS_USERNS_MOUNT is added
to allow creating BPF FS context object (i.e., fsopen("bpf")) from
inside unprivileged process inside non-init userns, to capture that
userns as the owning userns. It will still be required to pass this
context object back to privileged process to instantiate and mount it.
This manipulation is important, because capturing non-init userns as the
owning userns of BPF FS instance (super block) allows to use that userns
to constraint BPF token to that userns later on (see next patch). So
creating BPF FS with delegation inside unprivileged userns will restrict
derived BPF token objects to only "work" inside that intended userns,
making it scoped to a intended "container". Also, setting these
delegation options requires capable(CAP_SYS_ADMIN), so unprivileged
process cannot set this up without involvement of a privileged process.
There is a set of selftests at the end of the patch set that simulates
this sequence of steps and validates that everything works as intended.
But careful review is requested to make sure there are no missed gaps in
the implementation and testing.
This somewhat subtle set of aspects is the result of previous
discussions ([0]) about various user namespace implications and
interactions with BPF token functionality and is necessary to contain
BPF token inside intended user namespace.
[0] https://lore.kernel.org/bpf/20230704-hochverdient-lehne-eeb9eeef785e@brauner/
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Christian Brauner <brauner@kernel.org>
Link: https://lore.kernel.org/bpf/20240124022127.2379740-3-andrii@kernel.org
|
|
|
Andrii Nakryiko
|
ed1ad5a741 |
bpf: Align CAP_NET_ADMIN checks with bpf_capable() approach
Within BPF syscall handling code CAP_NET_ADMIN checks stand out a bit compared to CAP_BPF and CAP_PERFMON checks. For the latter, CAP_BPF or CAP_PERFMON are checked first, but if they are not set, CAP_SYS_ADMIN takes over and grants whatever part of BPF syscall is required. Similar kind of checks that involve CAP_NET_ADMIN are not so consistent. One out of four uses does follow CAP_BPF/CAP_PERFMON model: during BPF_PROG_LOAD, if the type of BPF program is "network-related" either CAP_NET_ADMIN or CAP_SYS_ADMIN is required to proceed. But in three other cases CAP_NET_ADMIN is required even if CAP_SYS_ADMIN is set: - when creating DEVMAP/XDKMAP/CPU_MAP maps; - when attaching CGROUP_SKB programs; - when handling BPF_PROG_QUERY command. This patch is changing the latter three cases to follow BPF_PROG_LOAD model, that is allowing to proceed under either CAP_NET_ADMIN or CAP_SYS_ADMIN. This also makes it cleaner in subsequent BPF token patches to switch wholesomely to a generic bpf_token_capable(int cap) check, that always falls back to CAP_SYS_ADMIN if requested capability is missing. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yafang Shao <laoar.shao@gmail.com> Link: https://lore.kernel.org/bpf/20240124022127.2379740-2-andrii@kernel.org |
|
|
Kui-Feng Lee
|
7c81c2490c |
bpf: export btf_ctx_access to modules.
The module requires the use of btf_ctx_access() to invoke bpf_tracing_btf_ctx_access() from a module. This function is valuable for implementing validation functions that ensure proper access to ctx. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-14-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
f6be98d199 |
bpf, net: switch to dynamic registration
Replace the static list of struct_ops types with per-btf struct_ops_tab to enable dynamic registration. Both bpf_dummy_ops and bpf_tcp_ca now utilize the registration function instead of being listed in bpf_struct_ops_types.h. Cc: netdev@vger.kernel.org Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-12-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
612d087d4b |
bpf: validate value_type
A value_type should consist of three components: refcnt, state, and data. refcnt and state has been move to struct bpf_struct_ops_common_value to make it easier to check the value type. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-11-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
e3f87fdfed |
bpf: hold module refcnt in bpf_struct_ops map creation and prog verification.
To ensure that a module remains accessible whenever a struct_ops object of a struct_ops type provided by the module is still in use. struct bpf_struct_ops_map doesn't hold a refcnt to btf anymore since a module will hold a refcnt to it's btf already. But, struct_ops programs are different. They hold their associated btf, not the module since they need only btf to assure their types (signatures). However, verifier holds the refcnt of the associated module of a struct_ops type temporarily when verify a struct_ops prog. Verifier needs the help from the verifier operators (struct bpf_verifier_ops) provided by the owner module to verify data access of a prog, provide information, and generate code. This patch also add a count of links (links_cnt) to bpf_struct_ops_map. It avoids bpf_struct_ops_map_put_progs() from accessing btf after calling module_put() in bpf_struct_ops_map_free(). Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-10-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
fcc2c1fb06 |
bpf: pass attached BTF to the bpf_struct_ops subsystem
Pass the fd of a btf from the userspace to the bpf() syscall, and then convert the fd into a btf. The btf is generated from the module that defines the target BPF struct_ops type. In order to inform the kernel about the module that defines the target struct_ops type, the userspace program needs to provide a btf fd for the respective module's btf. This btf contains essential information on the types defined within the module, including the target struct_ops type. A btf fd must be provided to the kernel for struct_ops maps and for the bpf programs attached to those maps. In the case of the bpf programs, the attach_btf_obj_fd parameter is passed as part of the bpf_attr and is converted into a btf. This btf is then stored in the prog->aux->attach_btf field. Here, it just let the verifier access attach_btf directly. In the case of struct_ops maps, a btf fd is passed as value_type_btf_obj_fd of bpf_attr. The bpf_struct_ops_map_alloc() function converts the fd to a btf and stores it as st_map->btf. A flag BPF_F_VTYPE_BTF_OBJ_FD is added for map_flags to indicate that the value of value_type_btf_obj_fd is set. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-9-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
689423db3b |
bpf: lookup struct_ops types from a given module BTF.
This is a preparation for searching for struct_ops types from a specified module. BTF is always btf_vmlinux now. This patch passes a pointer of BTF to bpf_struct_ops_find_value() and bpf_struct_ops_find(). Once the new registration API of struct_ops types is used, other BTFs besides btf_vmlinux can also be passed to them. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-8-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
1338b93346 |
bpf: pass btf object id in bpf_map_info.
Include btf object id (btf_obj_id) in bpf_map_info so that tools (ex: bpftools struct_ops dump) know the correct btf from the kernel to look up type information of struct_ops types. Since struct_ops types can be defined and registered in a module. The type information of a struct_ops type are defined in the btf of the module defining it. The userspace tools need to know which btf is for the module defining a struct_ops type. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-7-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
47f4f657ac |
bpf: make struct_ops_map support btfs other than btf_vmlinux.
Once new struct_ops can be registered from modules, btf_vmlinux is no longer the only btf that struct_ops_map would face. st_map should remember what btf it should use to get type information. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-6-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
e61995111a |
bpf: add struct_ops_tab to btf.
Maintain a registry of registered struct_ops types in the per-btf (module) struct_ops_tab. This registry allows for easy lookup of struct_ops types that are registered by a specific module. It is a preparation work for supporting kernel module struct_ops in a latter patch. Each struct_ops will be registered under its own kernel module btf and will be stored in the newly added btf->struct_ops_tab. The bpf verifier and bpf syscall (e.g. prog and map cmd) can find the struct_ops and its btf type/size/id... information from btf->struct_ops_tab. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-5-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
4c5763ed99 |
bpf, net: introduce bpf_struct_ops_desc.
Move some of members of bpf_struct_ops to bpf_struct_ops_desc. type_id is unavailabe in bpf_struct_ops anymore. Modules should get it from the btf received by kmod's init function. Cc: netdev@vger.kernel.org Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-4-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
9567839538 |
bpf: get type information with BTF_ID_LIST
Get ready to remove bpf_struct_ops_init() in the future. By using BTF_ID_LIST, it is possible to gather type information while building instead of runtime. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-3-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Kui-Feng Lee
|
3b1f89e747 |
bpf: refactory struct_ops type initialization to a function.
Move the majority of the code to bpf_struct_ops_init_one(), which can then be utilized for the initialization of newly registered dynamically allocated struct_ops types in the following patches. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240119225005.668602-2-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Jiri Olsa
|
d5c16492c6 |
bpf: Add cookie to perf_event bpf_link_info records
At the moment we don't store cookie for perf_event probes, while we do that for the rest of the probes. Adding cookie fields to struct bpf_link_info perf event probe records: perf_event.uprobe perf_event.kprobe perf_event.tracepoint perf_event.perf_event And the code to store that in bpf_link_info struct. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Song Liu <song@kernel.org> Acked-by: Yafang Shao <laoar.shao@gmail.com> Link: https://lore.kernel.org/r/20240119110505.400573-2-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Hao Sun
|
2ce793ebe2 |
bpf: Refactor ptr alu checking rules to allow alu explicitly
Current checking rules are structured to disallow alu on particular ptr
types explicitly, so default cases are allowed implicitly. This may lead
to newly added ptr types being allowed unexpectedly. So restruture it to
allow alu explicitly. The tradeoff is mainly a bit more cases added in
the switch. The following table from Eduard summarizes the rules:
| Pointer type | Arithmetics allowed |
|---------------------+---------------------|
| PTR_TO_CTX | yes |
| CONST_PTR_TO_MAP | conditionally |
| PTR_TO_MAP_VALUE | yes |
| PTR_TO_MAP_KEY | yes |
| PTR_TO_STACK | yes |
| PTR_TO_PACKET_META | yes |
| PTR_TO_PACKET | yes |
| PTR_TO_PACKET_END | no |
| PTR_TO_FLOW_KEYS | conditionally |
| PTR_TO_SOCKET | no |
| PTR_TO_SOCK_COMMON | no |
| PTR_TO_TCP_SOCK | no |
| PTR_TO_TP_BUFFER | yes |
| PTR_TO_XDP_SOCK | no |
| PTR_TO_BTF_ID | yes |
| PTR_TO_MEM | yes |
| PTR_TO_BUF | yes |
| PTR_TO_FUNC | yes |
| CONST_PTR_TO_DYNPTR | yes |
The refactored rules are equivalent to the original one. Note that
PTR_TO_FUNC and CONST_PTR_TO_DYNPTR are not reject here because: (1)
check_mem_access() rejects load/store on those ptrs, and those ptrs
with offset passing to calls are rejected check_func_arg_reg_off();
(2) someone may rely on the verifier not rejecting programs earily.
Signed-off-by: Hao Sun <sunhao.th@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240117094012.36798-1-sunhao.th@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Yonghong Song
|
9a4c57f52b |
bpf: Track aligned st store as imprecise spilled registers
With patch set [1], precision backtracing supports register spill/fill to/from the stack. The patch [2] allows initial imprecise register spill with content 0. This is a common case for cpuv3 and lower for initializing the stack variables with pattern r1 = 0 *(u64 *)(r10 - 8) = r1 and the [2] has demonstrated good verification improvement. For cpuv4, the initialization could be *(u64 *)(r10 - 8) = 0 The current verifier marks the r10-8 contents with STACK_ZERO. Similar to [2], let us permit the above insn to behave like imprecise register spill which can reduce number of verified states. The change is in function check_stack_write_fixed_off(). Before this patch, spilled zero will be marked as STACK_ZERO which can provide precise values. In check_stack_write_var_off(), STACK_ZERO will be maintained if writing a const zero so later it can provide precise values if needed. The above handling of '*(u64 *)(r10 - 8) = 0' as a spill will have issues in check_stack_write_var_off() as the spill will be converted to STACK_MISC and the precise value 0 is lost. To fix this issue, if the spill slots with const zero and the BPF_ST write also with const zero, the spill slots are preserved, which can later provide precise values if needed. Without the change in check_stack_write_var_off(), the test_verifier subtest 'BPF_ST_MEM stack imm zero, variable offset' will fail. I checked cpuv3 and cpuv4 with and without this patch with veristat. There is no state change for cpuv3 since '*(u64 *)(r10 - 8) = 0' is only generated with cpuv4. For cpuv4: $ ../veristat -C old.cpuv4.csv new.cpuv4.csv -e file,prog,insns,states -f 'insns_diff!=0' File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) ------------------------------------------ ------------------- --------- --------- --------------- ---------- ---------- ------------- local_storage_bench.bpf.linked3.o get_local 228 168 -60 (-26.32%) 17 14 -3 (-17.65%) pyperf600_bpf_loop.bpf.linked3.o on_event 6066 4889 -1177 (-19.40%) 403 321 -82 (-20.35%) test_cls_redirect.bpf.linked3.o cls_redirect 35483 35387 -96 (-0.27%) 2179 2177 -2 (-0.09%) test_l4lb_noinline.bpf.linked3.o balancer_ingress 4494 4522 +28 (+0.62%) 217 219 +2 (+0.92%) test_l4lb_noinline_dynptr.bpf.linked3.o balancer_ingress 1432 1455 +23 (+1.61%) 92 94 +2 (+2.17%) test_xdp_noinline.bpf.linked3.o balancer_ingress_v6 3462 3458 -4 (-0.12%) 216 216 +0 (+0.00%) verifier_iterating_callbacks.bpf.linked3.o widening 52 41 -11 (-21.15%) 4 3 -1 (-25.00%) xdp_synproxy_kern.bpf.linked3.o syncookie_tc 12412 11719 -693 (-5.58%) 345 330 -15 (-4.35%) xdp_synproxy_kern.bpf.linked3.o syncookie_xdp 12478 11794 -684 (-5.48%) 346 331 -15 (-4.34%) test_l4lb_noinline and test_l4lb_noinline_dynptr has minor regression, but pyperf600_bpf_loop and local_storage_bench gets pretty good improvement. [1] https://lore.kernel.org/all/20231205184248.1502704-1-andrii@kernel.org/ [2] https://lore.kernel.org/all/20231205184248.1502704-9-andrii@kernel.org/ Cc: Kuniyuki Iwashima <kuniyu@amazon.com> Cc: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Tested-by: Kuniyuki Iwashima <kuniyu@amazon.com> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240110051348.2737007-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Maxim Mikityanskiy
|
8ecfc371d8 |
bpf: Assign ID to scalars on spill
Currently, when a scalar bounded register is spilled to the stack, its ID is preserved, but only if was already assigned, i.e. if this register was MOVed before. Assign an ID on spill if none is set, so that equal scalars could be tracked if a register is spilled to the stack and filled into another register. One test is adjusted to reflect the change in register IDs. Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240108205209.838365-9-maxtram95@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Maxim Mikityanskiy
|
87e51ac6cb |
bpf: Add the get_reg_width function
Put calculation of the register value width into a dedicated function. This function will also be used in a following commit. Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com> Link: https://lore.kernel.org/r/20240108205209.838365-8-maxtram95@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Maxim Mikityanskiy
|
8e0e074aaf |
bpf: Add the assign_scalar_id_before_mov function
Extract the common code that generates a register ID for src_reg before MOV if needed into a new function. This function will also be used in a following commit. Signed-off-by: Maxim Mikityanskiy <maxim@isovalent.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240108205209.838365-7-maxtram95@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Eduard Zingerman
|
d5b892fd60 |
bpf: make infinite loop detection in is_state_visited() exact
Current infinite loops detection mechanism is speculative:
- first, states_maybe_looping() check is done which simply does memcmp
for R1-R10 in current frame;
- second, states_equal(..., exact=false) is called. With exact=false
states_equal() would compare scalars for equality only if in old
state scalar has precision mark.
Such logic might be problematic if compiler makes some unlucky stack
spill/fill decisions. An artificial example of a false positive looks
as follows:
r0 = ... unknown scalar ...
r0 &= 0xff;
*(u64 *)(r10 - 8) = r0;
r0 = 0;
loop:
r0 = *(u64 *)(r10 - 8);
if r0 > 10 goto exit_;
r0 += 1;
*(u64 *)(r10 - 8) = r0;
r0 = 0;
goto loop;
This commit updates call to states_equal to use exact=true, forcing
all scalar comparisons to be exact.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240108205209.838365-3-maxtram95@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
522bb2c1f8 |
bpf: support multiple tags per argument
Add ability to iterate multiple decl_tag types pointed to the same function argument. Use this to support multiple __arg_xxx tags per global subprog argument. We leave btf_find_decl_tag_value() intact, but change its implementation to use a new btf_find_next_decl_tag() which can be straightforwardly used to find next BTF type ID of a matching btf_decl_tag type. btf_prepare_func_args() is switched from btf_find_decl_tag_value() to btf_find_next_decl_tag() to gain multiple tags per argument support. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240105000909.2818934-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
54c11ec493 |
bpf: prepare btf_prepare_func_args() for multiple tags per argument
Add btf_arg_tag flags enum to be able to record multiple tags per argument. Also streamline pointer argument processing some more. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240105000909.2818934-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
18810ad392 |
bpf: make sure scalar args don't accept __arg_nonnull tag
Move scalar arg processing in btf_prepare_func_args() after all pointer arg processing is done. This makes it easier to do validation. One example of unintended behavior right now is ability to specify __arg_nonnull for integer/enum arguments. This patch fixes this. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20240105000909.2818934-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Hou Tao
|
7c05e7f3e7 |
bpf: Support inlining bpf_kptr_xchg() helper
The motivation of inlining bpf_kptr_xchg() comes from the performance profiling of bpf memory allocator benchmark. The benchmark uses bpf_kptr_xchg() to stash the allocated objects and to pop the stashed objects for free. After inling bpf_kptr_xchg(), the performance for object free on 8-CPUs VM increases about 2%~10%. The inline also has downside: both the kasan and kcsan checks on the pointer will be unavailable. bpf_kptr_xchg() can be inlined by converting the calling of bpf_kptr_xchg() into an atomic_xchg() instruction. But the conversion depends on two conditions: 1) JIT backend supports atomic_xchg() on pointer-sized word 2) For the specific arch, the implementation of xchg is the same as atomic_xchg() on pointer-sized words. It seems most 64-bit JIT backends satisfies these two conditions. But as a precaution, defining a weak function bpf_jit_supports_ptr_xchg() to state whether such conversion is safe and only supporting inline for 64-bit host. For x86-64, it supports BPF_XCHG atomic operation and both xchg() and atomic_xchg() use arch_xchg() to implement the exchange, so enabling the inline of bpf_kptr_xchg() on x86-64 first. Reviewed-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20240105104819.3916743-2-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
0ba971511d |
bpf: enforce types for __arg_ctx-tagged arguments in global subprogs
Add enforcement of expected types for context arguments tagged with
arg:ctx (__arg_ctx) tag.
First, any program type will accept generic `void *` context type when
combined with __arg_ctx tag.
Besides accepting "canonical" struct names and `void *`, for a bunch of
program types for which program context is actually a named struct, we
allows a bunch of pragmatic exceptions to match real-world and expected
usage:
- for both kprobes and perf_event we allow `bpf_user_pt_regs_t *` as
canonical context argument type, where `bpf_user_pt_regs_t` is a
*typedef*, not a struct;
- for kprobes, we also always accept `struct pt_regs *`, as that's what
actually is passed as a context to any kprobe program;
- for perf_event, we resolve typedefs (unless it's `bpf_user_pt_regs_t`)
down to actual struct type and accept `struct pt_regs *`, or
`struct user_pt_regs *`, or `struct user_regs_struct *`, depending
on the actual struct type kernel architecture points `bpf_user_pt_regs_t`
typedef to; otherwise, canonical `struct bpf_perf_event_data *` is
expected;
- for raw_tp/raw_tp.w programs, `u64/long *` are accepted, as that's
what's expected with BPF_PROG() usage; otherwise, canonical
`struct bpf_raw_tracepoint_args *` is expected;
- tp_btf supports both `struct bpf_raw_tracepoint_args *` and `u64 *`
formats, both are coded as expections as tp_btf is actually a TRACING
program type, which has no canonical context type;
- iterator programs accept `struct bpf_iter__xxx *` structs, currently
with no further iterator-type specific enforcement;
- fentry/fexit/fmod_ret/lsm/struct_ops all accept `u64 *`;
- classic tracepoint programs, as well as syscall and freplace
programs allow any user-provided type.
In all other cases kernel will enforce exact match of struct name to
expected canonical type. And if user-provided type doesn't match that
expectation, verifier will emit helpful message with expected type name.
Note a bit unnatural way the check is done after processing all the
arguments. This is done to avoid conflict between bpf and bpf-next
trees. Once trees converge, a small follow up patch will place a simple
btf_validate_prog_ctx_type() check into a proper ARG_PTR_TO_CTX branch
(which bpf-next tree patch refactored already), removing duplicated
arg:ctx detection logic.
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240118033143.3384355-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
66967a32d3 |
bpf: extract bpf_ctx_convert_map logic and make it more reusable
Refactor btf_get_prog_ctx_type() a bit to allow reuse of bpf_ctx_convert_map logic in more than one places. Simplify interface by returning btf_type instead of btf_member (field reference in BTF). To do the above we need to touch and start untangling btf_translate_to_vmlinux() implementation. We do the bare minimum to not regress anything for btf_translate_to_vmlinux(), but its implementation is very questionable for what it claims to be doing. Mapping kfunc argument types to kernel corresponding types conceptually is quite different from recognizing program context types. Fixing this is out of scope for this change though. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20240118033143.3384355-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Hao Sun
|
22c7fa171a |
bpf: Reject variable offset alu on PTR_TO_FLOW_KEYS
For PTR_TO_FLOW_KEYS, check_flow_keys_access() only uses fixed off
for validation. However, variable offset ptr alu is not prohibited
for this ptr kind. So the variable offset is not checked.
The following prog is accepted:
func#0 @0
0: R1=ctx() R10=fp0
0: (bf) r6 = r1 ; R1=ctx() R6_w=ctx()
1: (79) r7 = *(u64 *)(r6 +144) ; R6_w=ctx() R7_w=flow_keys()
2: (b7) r8 = 1024 ; R8_w=1024
3: (37) r8 /= 1 ; R8_w=scalar()
4: (57) r8 &= 1024 ; R8_w=scalar(smin=smin32=0,
smax=umax=smax32=umax32=1024,var_off=(0x0; 0x400))
5: (0f) r7 += r8
mark_precise: frame0: last_idx 5 first_idx 0 subseq_idx -1
mark_precise: frame0: regs=r8 stack= before 4: (57) r8 &= 1024
mark_precise: frame0: regs=r8 stack= before 3: (37) r8 /= 1
mark_precise: frame0: regs=r8 stack= before 2: (b7) r8 = 1024
6: R7_w=flow_keys(smin=smin32=0,smax=umax=smax32=umax32=1024,var_off
=(0x0; 0x400)) R8_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=1024,
var_off=(0x0; 0x400))
6: (79) r0 = *(u64 *)(r7 +0) ; R0_w=scalar()
7: (95) exit
This prog loads flow_keys to r7, and adds the variable offset r8
to r7, and finally causes out-of-bounds access:
BUG: unable to handle page fault for address: ffffc90014c80038
[...]
Call Trace:
<TASK>
bpf_dispatcher_nop_func include/linux/bpf.h:1231 [inline]
__bpf_prog_run include/linux/filter.h:651 [inline]
bpf_prog_run include/linux/filter.h:658 [inline]
bpf_prog_run_pin_on_cpu include/linux/filter.h:675 [inline]
bpf_flow_dissect+0x15f/0x350 net/core/flow_dissector.c:991
bpf_prog_test_run_flow_dissector+0x39d/0x620 net/bpf/test_run.c:1359
bpf_prog_test_run kernel/bpf/syscall.c:4107 [inline]
__sys_bpf+0xf8f/0x4560 kernel/bpf/syscall.c:5475
__do_sys_bpf kernel/bpf/syscall.c:5561 [inline]
__se_sys_bpf kernel/bpf/syscall.c:5559 [inline]
__x64_sys_bpf+0x73/0xb0 kernel/bpf/syscall.c:5559
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
Fix this by rejecting ptr alu with variable offset on flow_keys.
Applying the patch rejects the program with "R7 pointer arithmetic
on flow_keys prohibited".
Fixes:
|
|
|
Linus Torvalds
|
3e7aeb78ab |
Networking changes for 6.8.
Core & protocols
----------------
- Analyze and reorganize core networking structs (socks, netdev,
netns, mibs) to optimize cacheline consumption and set up
build time warnings to safeguard against future header changes.
This improves TCP performances with many concurrent connections
up to 40%.
- Add page-pool netlink-based introspection, exposing the
memory usage and recycling stats. This helps indentify
bad PP users and possible leaks.
- Refine TCP/DCCP source port selection to no longer favor even
source port at connect() time when IP_LOCAL_PORT_RANGE is set.
This lowers the time taken by connect() for hosts having
many active connections to the same destination.
- Refactor the TCP bind conflict code, shrinking related socket
structs.
- Refactor TCP SYN-Cookie handling, as a preparation step to
allow arbitrary SYN-Cookie processing via eBPF.
- Tune optmem_max for 0-copy usage, increasing the default value
to 128KB and namespecifying it.
- Allow coalescing for cloned skbs coming from page pools, improving
RX performances with some common configurations.
- Reduce extension header parsing overhead at GRO time.
- Add bridge MDB bulk deletion support, allowing user-space to
request the deletion of matching entries.
- Reorder nftables struct members, to keep data accessed by the
datapath first.
- Introduce TC block ports tracking and use. This allows supporting
multicast-like behavior at the TC layer.
- Remove UAPI support for retired TC qdiscs (dsmark, CBQ and ATM) and
classifiers (RSVP and tcindex).
- More data-race annotations.
- Extend the diag interface to dump TCP bound-only sockets.
- Conditional notification of events for TC qdisc class and actions.
- Support for WPAN dynamic associations with nearby devices, to form
a sub-network using a specific PAN ID.
- Implement SMCv2.1 virtual ISM device support.
- Add support for Batman-avd mulicast packet type.
BPF
---
- Tons of verifier improvements:
- BPF register bounds logic and range support along with a large
test suite
- log improvements
- complete precision tracking support for register spills
- track aligned STACK_ZERO cases as imprecise spilled registers. It
improves the verifier "instructions processed" metric from single
digit to 50-60% for some programs
- support for user's global BPF subprogram arguments with few
commonly requested annotations for a better developer experience
- support tracking of BPF_JNE which helps cases when the compiler
transforms (unsigned) "a > 0" into "if a == 0 goto xxx" and the
like
- several fixes
- Add initial TX metadata implementation for AF_XDP with support in
mlx5 and stmmac drivers. Two types of offloads are supported right
now, that is, TX timestamp and TX checksum offload.
- Fix kCFI bugs in BPF all forms of indirect calls from BPF into
kernel and from kernel into BPF work with CFI enabled. This allows
BPF to work with CONFIG_FINEIBT=y.
- Change BPF verifier logic to validate global subprograms lazily
instead of unconditionally before the main program, so they can be
guarded using BPF CO-RE techniques.
- Support uid/gid options when mounting bpffs.
- Add a new kfunc which acquires the associated cgroup of a task
within a specific cgroup v1 hierarchy where the latter is identified
by its id.
- Extend verifier to allow bpf_refcount_acquire() of a map value field
obtained via direct load which is a use-case needed in sched_ext.
- Add BPF link_info support for uprobe multi link along with bpftool
integration for the latter.
- Support for VLAN tag in XDP hints.
- Remove deprecated bpfilter kernel leftovers given the project
is developed in user-space (https://github.com/facebook/bpfilter).
Misc
----
- Support for parellel TC self-tests execution.
- Increase MPTCP self-tests coverage.
- Updated the bridge documentation, including several so-far
undocumented features.
- Convert all the net self-tests to run in unique netns, to
avoid random failures due to conflict and allow concurrent
runs.
- Add TCP-AO self-tests.
- Add kunit tests for both cfg80211 and mac80211.
- Autogenerate Netlink families documentation from YAML spec.
- Add yml-gen support for fixed headers and recursive nests, the
tool can now generate user-space code for all genetlink families
for which we have specs.
- A bunch of additional module descriptions fixes.
- Catch incorrect freeing of pages belonging to a page pool.
Driver API
----------
- Rust abstractions for network PHY drivers; do not cover yet the
full C API, but already allow implementing functional PHY drivers
in rust.
- Introduce queue and NAPI support in the netdev Netlink interface,
allowing complete access to the device <> NAPIs <> queues
relationship.
- Introduce notifications filtering for devlink to allow control
application scale to thousands of instances.
- Improve PHY validation, requesting rate matching information for
each ethtool link mode supported by both the PHY and host.
- Add support for ethtool symmetric-xor RSS hash.
- ACPI based Wifi band RFI (WBRF) mitigation feature for the AMD
platform.
- Expose pin fractional frequency offset value over new DPLL generic
netlink attribute.
- Convert older drivers to platform remove callback returning void.
- Add support for PHY package MMD read/write.
New hardware / drivers
----------------------
- Ethernet:
- Octeon CN10K devices
- Broadcom 5760X P7
- Qualcomm SM8550 SoC
- Texas Instrument DP83TG720S PHY
- Bluetooth:
- IMC Networks Bluetooth radio
Removed
-------
- WiFi:
- libertas 16-bit PCMCIA support
- Atmel at76c50x drivers
- HostAP ISA/PCMCIA style 802.11b driver
- zd1201 802.11b USB dongles
- Orinoco ISA/PCMCIA 802.11b driver
- Aviator/Raytheon driver
- Planet WL3501 driver
- RNDIS USB 802.11b driver
Drivers
-------
- Ethernet high-speed NICs:
- Intel (100G, ice, idpf):
- allow one by one port representors creation and removal
- add temperature and clock information reporting
- add get/set for ethtool's header split ringparam
- add again FW logging
- adds support switchdev hardware packet mirroring
- iavf: implement symmetric-xor RSS hash
- igc: add support for concurrent physical and free-running timers
- i40e: increase the allowable descriptors
- nVidia/Mellanox:
- Preparation for Socket-Direct multi-dev netdev. That will allow
in future releases combining multiple PFs devices attached to
different NUMA nodes under the same netdev
- Broadcom (bnxt):
- TX completion handling improvements
- add basic ntuple filter support
- reduce MSIX vectors usage for MQPRIO offload
- add VXLAN support, USO offload and TX coalesce completion for P7
- Marvell Octeon EP:
- xmit-more support
- add PF-VF mailbox support and use it for FW notifications for VFs
- Wangxun (ngbe/txgbe):
- implement ethtool functions to operate pause param, ring param,
coalesce channel number and msglevel
- Netronome/Corigine (nfp):
- add flow-steering support
- support UDP segmentation offload
- Ethernet NICs embedded, slower, virtual:
- Xilinx AXI: remove duplicate DMA code adopting the dma engine driver
- stmmac: add support for HW-accelerated VLAN stripping
- TI AM654x sw: add mqprio, frame preemption & coalescing
- gve: add support for non-4k page sizes.
- virtio-net: support dynamic coalescing moderation
- nVidia/Mellanox Ethernet datacenter switches:
- allow firmware upgrade without a reboot
- more flexible support for bridge flooding via the compressed
FID flooding mode
- Ethernet embedded switches:
- Microchip:
- fine-tune flow control and speed configurations in KSZ8xxx
- KSZ88X3: enable setting rmii reference
- Renesas:
- add jumbo frames support
- Marvell:
- 88E6xxx: add "eth-mac" and "rmon" stats support
- Ethernet PHYs:
- aquantia: add firmware load support
- at803x: refactor the driver to simplify adding support for more
chip variants
- NXP C45 TJA11xx: Add MACsec offload support
- Wifi:
- MediaTek (mt76):
- NVMEM EEPROM improvements
- mt7996 Extremely High Throughput (EHT) improvements
- mt7996 Wireless Ethernet Dispatcher (WED) support
- mt7996 36-bit DMA support
- Qualcomm (ath12k):
- support for a single MSI vector
- WCN7850: support AP mode
- Intel (iwlwifi):
- new debugfs file fw_dbg_clear
- allow concurrent P2P operation on DFS channels
- Bluetooth:
- QCA2066: support HFP offload
- ISO: more broadcast-related improvements
- NXP: better recovery in case receiver/transmitter get out of sync
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
-----BEGIN PGP SIGNATURE-----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=1bW6
-----END PGP SIGNATURE-----
Merge tag 'net-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Paolo Abeni:
"The most interesting thing is probably the networking structs
reorganization and a significant amount of changes is around
self-tests.
Core & protocols:
- Analyze and reorganize core networking structs (socks, netdev,
netns, mibs) to optimize cacheline consumption and set up build
time warnings to safeguard against future header changes
This improves TCP performances with many concurrent connections up
to 40%
- Add page-pool netlink-based introspection, exposing the memory
usage and recycling stats. This helps indentify bad PP users and
possible leaks
- Refine TCP/DCCP source port selection to no longer favor even
source port at connect() time when IP_LOCAL_PORT_RANGE is set. This
lowers the time taken by connect() for hosts having many active
connections to the same destination
- Refactor the TCP bind conflict code, shrinking related socket
structs
- Refactor TCP SYN-Cookie handling, as a preparation step to allow
arbitrary SYN-Cookie processing via eBPF
- Tune optmem_max for 0-copy usage, increasing the default value to
128KB and namespecifying it
- Allow coalescing for cloned skbs coming from page pools, improving
RX performances with some common configurations
- Reduce extension header parsing overhead at GRO time
- Add bridge MDB bulk deletion support, allowing user-space to
request the deletion of matching entries
- Reorder nftables struct members, to keep data accessed by the
datapath first
- Introduce TC block ports tracking and use. This allows supporting
multicast-like behavior at the TC layer
- Remove UAPI support for retired TC qdiscs (dsmark, CBQ and ATM) and
classifiers (RSVP and tcindex)
- More data-race annotations
- Extend the diag interface to dump TCP bound-only sockets
- Conditional notification of events for TC qdisc class and actions
- Support for WPAN dynamic associations with nearby devices, to form
a sub-network using a specific PAN ID
- Implement SMCv2.1 virtual ISM device support
- Add support for Batman-avd mulicast packet type
BPF:
- Tons of verifier improvements:
- BPF register bounds logic and range support along with a large
test suite
- log improvements
- complete precision tracking support for register spills
- track aligned STACK_ZERO cases as imprecise spilled registers.
This improves the verifier "instructions processed" metric from
single digit to 50-60% for some programs
- support for user's global BPF subprogram arguments with few
commonly requested annotations for a better developer
experience
- support tracking of BPF_JNE which helps cases when the compiler
transforms (unsigned) "a > 0" into "if a == 0 goto xxx" and the
like
- several fixes
- Add initial TX metadata implementation for AF_XDP with support in
mlx5 and stmmac drivers. Two types of offloads are supported right
now, that is, TX timestamp and TX checksum offload
- Fix kCFI bugs in BPF all forms of indirect calls from BPF into
kernel and from kernel into BPF work with CFI enabled. This allows
BPF to work with CONFIG_FINEIBT=y
- Change BPF verifier logic to validate global subprograms lazily
instead of unconditionally before the main program, so they can be
guarded using BPF CO-RE techniques
- Support uid/gid options when mounting bpffs
- Add a new kfunc which acquires the associated cgroup of a task
within a specific cgroup v1 hierarchy where the latter is
identified by its id
- Extend verifier to allow bpf_refcount_acquire() of a map value
field obtained via direct load which is a use-case needed in
sched_ext
- Add BPF link_info support for uprobe multi link along with bpftool
integration for the latter
- Support for VLAN tag in XDP hints
- Remove deprecated bpfilter kernel leftovers given the project is
developed in user-space (https://github.com/facebook/bpfilter)
Misc:
- Support for parellel TC self-tests execution
- Increase MPTCP self-tests coverage
- Updated the bridge documentation, including several so-far
undocumented features
- Convert all the net self-tests to run in unique netns, to avoid
random failures due to conflict and allow concurrent runs
- Add TCP-AO self-tests
- Add kunit tests for both cfg80211 and mac80211
- Autogenerate Netlink families documentation from YAML spec
- Add yml-gen support for fixed headers and recursive nests, the tool
can now generate user-space code for all genetlink families for
which we have specs
- A bunch of additional module descriptions fixes
- Catch incorrect freeing of pages belonging to a page pool
Driver API:
- Rust abstractions for network PHY drivers; do not cover yet the
full C API, but already allow implementing functional PHY drivers
in rust
- Introduce queue and NAPI support in the netdev Netlink interface,
allowing complete access to the device <> NAPIs <> queues
relationship
- Introduce notifications filtering for devlink to allow control
application scale to thousands of instances
- Improve PHY validation, requesting rate matching information for
each ethtool link mode supported by both the PHY and host
- Add support for ethtool symmetric-xor RSS hash
- ACPI based Wifi band RFI (WBRF) mitigation feature for the AMD
platform
- Expose pin fractional frequency offset value over new DPLL generic
netlink attribute
- Convert older drivers to platform remove callback returning void
- Add support for PHY package MMD read/write
New hardware / drivers:
- Ethernet:
- Octeon CN10K devices
- Broadcom 5760X P7
- Qualcomm SM8550 SoC
- Texas Instrument DP83TG720S PHY
- Bluetooth:
- IMC Networks Bluetooth radio
Removed:
- WiFi:
- libertas 16-bit PCMCIA support
- Atmel at76c50x drivers
- HostAP ISA/PCMCIA style 802.11b driver
- zd1201 802.11b USB dongles
- Orinoco ISA/PCMCIA 802.11b driver
- Aviator/Raytheon driver
- Planet WL3501 driver
- RNDIS USB 802.11b driver
Driver updates:
- Ethernet high-speed NICs:
- Intel (100G, ice, idpf):
- allow one by one port representors creation and removal
- add temperature and clock information reporting
- add get/set for ethtool's header split ringparam
- add again FW logging
- adds support switchdev hardware packet mirroring
- iavf: implement symmetric-xor RSS hash
- igc: add support for concurrent physical and free-running
timers
- i40e: increase the allowable descriptors
- nVidia/Mellanox:
- Preparation for Socket-Direct multi-dev netdev. That will
allow in future releases combining multiple PFs devices
attached to different NUMA nodes under the same netdev
- Broadcom (bnxt):
- TX completion handling improvements
- add basic ntuple filter support
- reduce MSIX vectors usage for MQPRIO offload
- add VXLAN support, USO offload and TX coalesce completion
for P7
- Marvell Octeon EP:
- xmit-more support
- add PF-VF mailbox support and use it for FW notifications
for VFs
- Wangxun (ngbe/txgbe):
- implement ethtool functions to operate pause param, ring
param, coalesce channel number and msglevel
- Netronome/Corigine (nfp):
- add flow-steering support
- support UDP segmentation offload
- Ethernet NICs embedded, slower, virtual:
- Xilinx AXI: remove duplicate DMA code adopting the dma engine
driver
- stmmac: add support for HW-accelerated VLAN stripping
- TI AM654x sw: add mqprio, frame preemption & coalescing
- gve: add support for non-4k page sizes.
- virtio-net: support dynamic coalescing moderation
- nVidia/Mellanox Ethernet datacenter switches:
- allow firmware upgrade without a reboot
- more flexible support for bridge flooding via the compressed
FID flooding mode
- Ethernet embedded switches:
- Microchip:
- fine-tune flow control and speed configurations in KSZ8xxx
- KSZ88X3: enable setting rmii reference
- Renesas:
- add jumbo frames support
- Marvell:
- 88E6xxx: add "eth-mac" and "rmon" stats support
- Ethernet PHYs:
- aquantia: add firmware load support
- at803x: refactor the driver to simplify adding support for more
chip variants
- NXP C45 TJA11xx: Add MACsec offload support
- Wifi:
- MediaTek (mt76):
- NVMEM EEPROM improvements
- mt7996 Extremely High Throughput (EHT) improvements
- mt7996 Wireless Ethernet Dispatcher (WED) support
- mt7996 36-bit DMA support
- Qualcomm (ath12k):
- support for a single MSI vector
- WCN7850: support AP mode
- Intel (iwlwifi):
- new debugfs file fw_dbg_clear
- allow concurrent P2P operation on DFS channels
- Bluetooth:
- QCA2066: support HFP offload
- ISO: more broadcast-related improvements
- NXP: better recovery in case receiver/transmitter get out of sync"
* tag 'net-next-6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1714 commits)
lan78xx: remove redundant statement in lan78xx_get_eee
lan743x: remove redundant statement in lan743x_ethtool_get_eee
bnxt_en: Fix RCU locking for ntuple filters in bnxt_rx_flow_steer()
bnxt_en: Fix RCU locking for ntuple filters in bnxt_srxclsrldel()
bnxt_en: Remove unneeded variable in bnxt_hwrm_clear_vnic_filter()
tcp: Revert no longer abort SYN_SENT when receiving some ICMP
Revert "mlx5 updates 2023-12-20"
Revert "net: stmmac: Enable Per DMA Channel interrupt"
ipvlan: Remove usage of the deprecated ida_simple_xx() API
ipvlan: Fix a typo in a comment
net/sched: Remove ipt action tests
net: stmmac: Use interrupt mode INTM=1 for per channel irq
net: stmmac: Add support for TX/RX channel interrupt
net: stmmac: Make MSI interrupt routine generic
dt-bindings: net: snps,dwmac: per channel irq
net: phy: at803x: make read_status more generic
net: phy: at803x: add support for cdt cross short test for qca808x
net: phy: at803x: refactor qca808x cable test get status function
net: phy: at803x: generalize cdt fault length function
net: ethernet: cortina: Drop TSO support
...
|
|
Jiri Olsa
|
715d82ba63 |
bpf: Fix re-attachment branch in bpf_tracing_prog_attach
The following case can cause a crash due to missing attach_btf:
1) load rawtp program
2) load fentry program with rawtp as target_fd
3) create tracing link for fentry program with target_fd = 0
4) repeat 3
In the end we have:
- prog->aux->dst_trampoline == NULL
- tgt_prog == NULL (because we did not provide target_fd to link_create)
- prog->aux->attach_btf == NULL (the program was loaded with attach_prog_fd=X)
- the program was loaded for tgt_prog but we have no way to find out which one
BUG: kernel NULL pointer dereference, address: 0000000000000058
Call Trace:
<TASK>
? __die+0x20/0x70
? page_fault_oops+0x15b/0x430
? fixup_exception+0x22/0x330
? exc_page_fault+0x6f/0x170
? asm_exc_page_fault+0x22/0x30
? bpf_tracing_prog_attach+0x279/0x560
? btf_obj_id+0x5/0x10
bpf_tracing_prog_attach+0x439/0x560
__sys_bpf+0x1cf4/0x2de0
__x64_sys_bpf+0x1c/0x30
do_syscall_64+0x41/0xf0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
Return -EINVAL in this situation.
Fixes:
|
|
Dmitrii Dolgov
|
19bfcdf949 |
bpf: Relax tracing prog recursive attach rules
Currently, it's not allowed to attach an fentry/fexit prog to another one fentry/fexit. At the same time it's not uncommon to see a tracing program with lots of logic in use, and the attachment limitation prevents usage of fentry/fexit for performance analysis (e.g. with "bpftool prog profile" command) in this case. An example could be falcosecurity libs project that uses tp_btf tracing programs. Following the corresponding discussion [1], the reason for that is to avoid tracing progs call cycles without introducing more complex solutions. But currently it seems impossible to load and attach tracing programs in a way that will form such a cycle. The limitation is coming from the fact that attach_prog_fd is specified at the prog load (thus making it impossible to attach to a program loaded after it in this way), as well as tracing progs not implementing link_detach. Replace "no same type" requirement with verification that no more than one level of attachment nesting is allowed. In this way only one fentry/fexit program could be attached to another fentry/fexit to cover profiling use case, and still no cycle could be formed. To implement, add a new field into bpf_prog_aux to track nested attachment for tracing programs. [1]: https://lore.kernel.org/bpf/20191108064039.2041889-16-ast@kernel.org/ Acked-by: Jiri Olsa <olsajiri@gmail.com> Acked-by: Song Liu <song@kernel.org> Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com> Link: https://lore.kernel.org/r/20240103190559.14750-2-9erthalion6@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Yonghong Song
|
9ddf872b47 |
bpf: Remove unnecessary cpu == 0 check in memalloc
After merging the patch set [1] to reduce memory usage for bpf_global_percpu_ma, Alexei found a redundant check (cpu == 0) in function bpf_mem_alloc_percpu_unit_init() ([2]). Indeed, the check is unnecessary since c->unit_size will be all NULL or all non-NULL for all cpus before for_each_possible_cpu() loop. Removing the check makes code less confusing. [1] https://lore.kernel.org/all/20231222031729.1287957-1-yonghong.song@linux.dev/ [2] https://lore.kernel.org/all/20231222031745.1289082-1-yonghong.song@linux.dev/ Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20240104165744.702239-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Yonghong Song
|
5c1a376532 |
bpf: Limit up to 512 bytes for bpf_global_percpu_ma allocation
For percpu data structure allocation with bpf_global_percpu_ma, the maximum data size is 4K. But for a system with large number of cpus, bigger data size (e.g., 2K, 4K) might consume a lot of memory. For example, the percpu memory consumption with unit size 2K and 1024 cpus will be 2K * 1K * 1k = 2GB memory. We should discourage such usage. Let us limit the maximum data size to be 512 for bpf_global_percpu_ma allocation. Acked-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20231222031801.1290841-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Yonghong Song
|
0e2ba9f96f |
bpf: Use smaller low/high marks for percpu allocation
Currently, refill low/high marks are set with the assumption of normal non-percpu memory allocation. For example, for an allocation size 256, for non-percpu memory allocation, low mark is 32 and high mark is 96, resulting in the batch allocation of 48 elements and the allocated memory will be 48 * 256 = 12KB for this particular cpu. Assuming an 128-cpu system, the total memory consumption across all cpus will be 12K * 128 = 1.5MB memory. This might be okay for non-percpu allocation, but may not be good for percpu allocation, which will consume 1.5MB * 128 = 192MB memory in the worst case if every cpu has a chance of memory allocation. In practice, percpu allocation is very rare compared to non-percpu allocation. So let us have smaller low/high marks which can avoid unnecessary memory consumption. Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Acked-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231222031755.1289671-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Yonghong Song
|
5b95e638f1 |
bpf: Refill only one percpu element in memalloc
Typically for percpu map element or data structure, once allocated, most operations are lookup or in-place update. Deletion are really rare. Currently, for percpu data strcture, 4 elements will be refilled if the size is <= 256. Let us just do with one element for percpu data. For example, for size 256 and 128 cpus, the potential saving will be 3 * 256 * 128 * 128 = 12MB. Acked-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20231222031750.1289290-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Yonghong Song
|
c39aa3b289 |
bpf: Allow per unit prefill for non-fix-size percpu memory allocator
Commit |
|
|
Yonghong Song
|
9fc8e80204 |
bpf: Add objcg to bpf_mem_alloc
The objcg is a bpf_mem_alloc level property since all bpf_mem_cache's are with the same objcg. This patch made such a property explicit. The next patch will use this property to save and restore objcg for percpu unit allocator. Acked-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20231222031739.1288590-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Yonghong Song
|
9beda16c25 |
bpf: Avoid unnecessary extra percpu memory allocation
Currently, for percpu memory allocation, say if the user requests allocation size to be 32 bytes, the actually calculated size will be 40 bytes and it further rounds to 64 bytes, and eventually 64 bytes are allocated, wasting 32-byte memory. Change bpf_mem_alloc() to calculate the cache index based on the user-provided allocation size so unnecessary extra memory can be avoided. Suggested-by: Hou Tao <houtao1@huawei.com> Acked-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20231222031734.1288400-1-yonghong.song@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrei Matei
|
8a021e7fa1 |
bpf: Simplify checking size of helper accesses
This patch simplifies the verification of size arguments associated to pointer arguments to helpers and kfuncs. Many helpers take a pointer argument followed by the size of the memory access performed to be performed through that pointer. Before this patch, the handling of the size argument in check_mem_size_reg() was confusing and wasteful: if the size register's lower bound was 0, then the verification was done twice: once considering the size of the access to be the lower-bound of the respective argument, and once considering the upper bound (even if the two are the same). The upper bound checking is a super-set of the lower-bound checking(*), except: the only point of the lower-bound check is to handle the case where zero-sized-accesses are explicitly not allowed and the lower-bound is zero. This static condition is now checked explicitly, replacing a much more complex, expensive and confusing verification call to check_helper_mem_access(). Error messages change in this patch. Before, messages about illegal zero-size accesses depended on the type of the pointer and on other conditions, and sometimes the message was plain wrong: in some tests that changed you'll see that the old message was something like "R1 min value is outside of the allowed memory range", where R1 is the pointer register; the error was wrongly claiming that the pointer was bad instead of the size being bad. Other times the information that the size came for a register with a possible range of values was wrong, and the error presented the size as a fixed zero. Now the errors refer to the right register. However, the old error messages did contain useful information about the pointer register which is now lost; recovering this information was deemed not important enough. (*) Besides standing to reason that the checks for a bigger size access are a super-set of the checks for a smaller size access, I have also mechanically verified this by reading the code for all types of pointers. I could convince myself that it's true for all but PTR_TO_BTF_ID (check_ptr_to_btf_access). There, simply looking line-by-line does not immediately prove what we want. If anyone has any qualms, let me know. Signed-off-by: Andrei Matei <andreimatei1@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20231221232225.568730-2-andreimatei1@gmail.com |
|
Kent Overstreet
|
1e2f2d3199 |
Kill sched.h dependency on rcupdate.h
by moving cond_resched_rcu() to rcupdate_wait.h, we can kill another big sched.h dependency. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev> |
|
Simon Horman
|
5abde62465 |
bpf: Avoid unnecessary use of comma operator in verifier
Although it does not seem to have any untoward side-effects, the use of ';' to separate to assignments seems more appropriate than ','. Flagged by clang-17 -Wcomma No functional change intended. Compile tested only. Signed-off-by: Simon Horman <horms@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Dave Marchevsky <davemarchevsky@fb.com> Link: https://lore.kernel.org/bpf/20231221-bpf-verifier-comma-v1-1-cde2530912e9@kernel.org |
|
|
Daniel Borkmann
|
b08c8fc041 |
bpf: Re-support uid and gid when mounting bpffs
For a clean, conflict-free revert of the token-related patches in commit |
|
|
Hou Tao
|
7ac5c53e00 |
bpf: Use c->unit_size to select target cache during free
At present, bpf memory allocator uses check_obj_size() to ensure that
ksize() of allocated pointer is equal with the unit_size of used
bpf_mem_cache. Its purpose is to prevent bpf_mem_free() from selecting
a bpf_mem_cache which has different unit_size compared with the
bpf_mem_cache used for allocation. But as reported by lkp, the return
value of ksize() or kmalloc_size_roundup() may change due to slab merge
and it will lead to the warning report in check_obj_size().
The reported warning happened as follows:
(1) in bpf_mem_cache_adjust_size(), kmalloc_size_roundup(96) returns the
object_size of kmalloc-96 instead of kmalloc-cg-96. The object_size of
kmalloc-96 is 96, so size_index for 96 is not adjusted accordingly.
(2) the object_size of kmalloc-cg-96 is adjust from 96 to 128 due to
slab merge in __kmem_cache_alias(). For SLAB, SLAB_HWCACHE_ALIGN is
enabled by default for kmalloc slab, so align is 64 and size is 128 for
kmalloc-cg-96. SLUB has a similar merge logic, but its object_size will
not be changed, because its align is 8 under x86-64.
(3) when unit_alloc() does kmalloc_node(96, __GFP_ACCOUNT, node),
ksize() returns 128 instead of 96 for the returned pointer.
(4) the warning in check_obj_size() is triggered.
Considering the slab merge can happen in anytime (e.g, a slab created in
a new module), the following case is also possible: during the
initialization of bpf_global_ma, there is no slab merge and ksize() for
a 96-bytes object returns 96. But after that a new slab created by a
kernel module is merged to kmalloc-cg-96 and the object_size of
kmalloc-cg-96 is adjust from 96 to 128 (which is possible for x86-64 +
CONFIG_SLAB, because its alignment requirement is 64 for 96-bytes slab).
So soon or later, when bpf_global_ma frees a 96-byte-sized pointer
which is allocated from bpf_mem_cache with unit_size=96, bpf_mem_free()
will free the pointer through a bpf_mem_cache in which unit_size is 128,
because the return value of ksize() changes. The warning for the
mismatch will be triggered again.
A feasible fix is introducing similar APIs compared with ksize() and
kmalloc_size_roundup() to return the actually-allocated size instead of
size which may change due to slab merge, but it will introduce
unnecessary dependency on the implementation details of mm subsystem.
As for now the pointer of bpf_mem_cache is saved in the 8-bytes area
(or 4-bytes under 32-bit host) above the returned pointer, using
unit_size in the saved bpf_mem_cache to select the target cache instead
of inferring the size from the pointer itself. Beside no extra
dependency on mm subsystem, the performance for bpf_mem_free_rcu() is
also improved as shown below.
Before applying the patch, the performances of bpf_mem_alloc() and
bpf_mem_free_rcu() on 8-CPUs VM with one producer are as follows:
kmalloc : alloc 11.69 ± 0.28M/s free 29.58 ± 0.93M/s
percpu : alloc 14.11 ± 0.52M/s free 14.29 ± 0.99M/s
After apply the patch, the performance for bpf_mem_free_rcu() increases
9% and 146% for kmalloc memory and per-cpu memory respectively:
kmalloc: alloc 11.01 ± 0.03M/s free 32.42 ± 0.48M/s
percpu: alloc 12.84 ± 0.12M/s free 35.24 ± 0.23M/s
After the fixes, there is no need to adjust size_index to fix the
mismatch between allocation and free, so remove it as well. Also return
NULL instead of ZERO_SIZE_PTR for zero-sized alloc in bpf_mem_alloc(),
because there is no bpf_mem_cache pointer saved above ZERO_SIZE_PTR.
Fixes:
|
|
|
Andrii Nakryiko
|
a64bfe6186 |
bpf: add support for passing dynptr pointer to global subprog
Add ability to pass a pointer to dynptr into global functions. This allows to have global subprogs that accept and work with generic dynptrs that are created by caller. Dynptr argument is detected based on the name of a struct type, if it's "bpf_dynptr", it's assumed to be a proper dynptr pointer. Both actual struct and forward struct declaration types are supported. This is conceptually exactly the same semantics as bpf_user_ringbuf_drain()'s use of dynptr to pass a variable-sized pointer to ringbuf record. So we heavily rely on CONST_PTR_TO_DYNPTR bits of already existing logic in the verifier. During global subprog validation, we mark such CONST_PTR_TO_DYNPTR as having LOCAL type, as that's the most unassuming type of dynptr and it doesn't have any special helpers that can try to free or acquire extra references (unlike skb, xdp, or ringbuf dynptr). So that seems like a safe "choice" to make from correctness standpoint. It's still possible to pass any type of dynptr to such subprog, though, because generic dynptr helpers, like getting data/slice pointers, read/write memory copying routines, dynptr adjustment and getter routines all work correctly with any type of dynptr. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231215011334.2307144-8-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
94e1c70a34 |
bpf: support 'arg:xxx' btf_decl_tag-based hints for global subprog args
Add support for annotating global BPF subprog arguments to provide more
information about expected semantics of the argument. Currently,
verifier relies purely on argument's BTF type information, and supports
three general use cases: scalar, pointer-to-context, and
pointer-to-fixed-size-memory.
Scalar and pointer-to-fixed-mem work well in practice and are quite
natural to use. But pointer-to-context is a bit problematic, as typical
BPF users don't realize that they need to use a special type name to
signal to verifier that argument is not just some pointer, but actually
a PTR_TO_CTX. Further, even if users do know which type to use, it is
limiting in situations where the same BPF program logic is used across
few different program types. Common case is kprobes, tracepoints, and
perf_event programs having a helper to send some data over BPF perf
buffer. bpf_perf_event_output() requires `ctx` argument, and so it's
quite cumbersome to share such global subprog across few BPF programs of
different types, necessitating extra static subprog that is context
type-agnostic.
Long story short, there is a need to go beyond types and allow users to
add hints to global subprog arguments to define expectations.
This patch adds such support for two initial special tags:
- pointer to context;
- non-null qualifier for generic pointer arguments.
All of the above came up in practice already and seem generally useful
additions. Non-null qualifier is an often requested feature, which
currently has to be worked around by having unnecessary NULL checks
inside subprogs even if we know that arguments are never NULL. Pointer
to context was discussed earlier.
As for implementation, we utilize btf_decl_tag attribute and set up an
"arg:xxx" convention to specify argument hint. As such:
- btf_decl_tag("arg:ctx") is a PTR_TO_CTX hint;
- btf_decl_tag("arg:nonnull") marks pointer argument as not allowed to
be NULL, making NULL check inside global subprog unnecessary.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231215011334.2307144-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
f18c3d88de |
bpf: reuse subprog argument parsing logic for subprog call checks
Remove duplicated BTF parsing logic when it comes to subprog call check. Instead, use (potentially cached) results of btf_prepare_func_args() to abstract away expectations of each subprog argument in generic terms (e.g., "this is pointer to context", or "this is a pointer to memory of size X"), and then use those simple high-level argument type expectations to validate actual register states to check if they match expectations. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231215011334.2307144-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
c5a7244759 |
bpf: move subprog call logic back to verifier.c
Subprog call logic in btf_check_subprog_call() currently has both a lot of BTF parsing logic (which is, presumably, what justified putting it into btf.c), but also a bunch of register state checks, some of each utilize deep verifier logic helpers, necessarily exported from verifier.c: check_ptr_off_reg(), check_func_arg_reg_off(), and check_mem_reg(). Going forward, btf_check_subprog_call() will have a minimum of BTF-related logic, but will get more internal verifier logic related to register state manipulation. So move it into verifier.c to minimize amount of verifier-specific logic exposed to btf.c. We do this move before refactoring btf_check_func_arg_match() to preserve as much history post-refactoring as possible. No functional changes. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231215011334.2307144-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
e26080d0da |
bpf: prepare btf_prepare_func_args() for handling static subprogs
Generalize btf_prepare_func_args() to support both global and static subprogs. We are going to utilize this property in the next patch, reusing btf_prepare_func_args() for subprog call logic instead of reparsing BTF information in a completely separate implementation. btf_prepare_func_args() now detects whether subprog is global or static makes slight logic adjustments for static func cases, like not failing fatally (-EFAULT) for conditions that are allowable for static subprogs. Somewhat subtle (but major!) difference is the handling of pointer arguments. Both global and static functions need to handle special context arguments (which are pointers to predefined type names), but static subprogs give up on any other pointers, falling back to marking subprog as "unreliable", disabling the use of BTF type information altogether. For global functions, though, we are assuming that such pointers to unrecognized types are just pointers to fixed-sized memory region (or error out if size cannot be established, like for `void *` pointers). This patch accommodates these small differences and sets up a stage for refactoring in the next patch, eliminating a separate BTF-based parsing logic in btf_check_func_arg_match(). Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231215011334.2307144-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
5eccd2db42 |
bpf: reuse btf_prepare_func_args() check for main program BTF validation
Instead of btf_check_subprog_arg_match(), use btf_prepare_func_args() logic to validate "trustworthiness" of main BPF program's BTF information, if it is present. We ignored results of original BTF check anyway, often times producing confusing and ominously-sounding "reg type unsupported for arg#0 function" message, which has no apparent effect on program correctness and verification process. All the -EFAULT returning sanity checks are already performed in check_btf_info_early(), so there is zero reason to have this duplication of logic between btf_check_subprog_call() and btf_check_subprog_arg_match(). Dropping btf_check_subprog_arg_match() simplifies btf_check_func_arg_match() further removing `bool processing_call` flag. One subtle bit that was done by btf_check_subprog_arg_match() was potentially marking main program's BTF as unreliable. We do this explicitly now with a dedicated simple check, preserving the original behavior, but now based on well factored btf_prepare_func_args() logic. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231215011334.2307144-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
4ba1d0f234 |
bpf: abstract away global subprog arg preparation logic from reg state setup
btf_prepare_func_args() is used to understand expectations and restrictions on global subprog arguments. But current implementation is hard to extend, as it intermixes BTF-based func prototype parsing and interpretation logic with setting up register state at subprog entry. Worse still, those registers are not completely set up inside btf_prepare_func_args(), requiring some more logic later in do_check_common(). Like calling mark_reg_unknown() and similar initialization operations. This intermixing of BTF interpretation and register state setup is problematic. First, it causes duplication of BTF parsing logic for global subprog verification (to set up initial state of global subprog) and global subprog call sites analysis (when we need to check that whatever is being passed into global subprog matches expectations), performed in btf_check_subprog_call(). Given we want to extend global func argument with tags later, this duplication is problematic. So refactor btf_prepare_func_args() to do only BTF-based func proto and args parsing, returning high-level argument "expectations" only, with no regard to specifics of register state. I.e., if it's a context argument, instead of setting register state to PTR_TO_CTX, we return ARG_PTR_TO_CTX enum for that argument as "an argument specification" for further processing inside do_check_common(). Similarly for SCALAR arguments, PTR_TO_MEM, etc. This allows to reuse btf_prepare_func_args() in following patches at global subprog call site analysis time. It also keeps register setup code consistently in one place, do_check_common(). Besides all this, we cache this argument specs information inside env->subprog_info, eliminating the need to redo these potentially expensive BTF traversals, especially if BPF program's BTF is big and/or there are lots of global subprog calls. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231215011334.2307144-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Menglong Dong
|
d028f87517 |
bpf: make the verifier tracks the "not equal" for regs
We can derive some new information for BPF_JNE in regs_refine_cond_op().
Take following code for example:
/* The type of "a" is u32 */
if (a > 0 && a < 100) {
/* the range of the register for a is [0, 99], not [1, 99],
* and will cause the following error:
*
* invalid zero-sized read
*
* as a can be 0.
*/
bpf_skb_store_bytes(skb, xx, xx, a, 0);
}
In the code above, "a > 0" will be compiled to "jmp xxx if a == 0". In the
TRUE branch, the dst_reg will be marked as known to 0. However, in the
fallthrough(FALSE) branch, the dst_reg will not be handled, which makes
the [min, max] for a is [0, 99], not [1, 99].
For BPF_JNE, we can reduce the range of the dst reg if the src reg is a
const and is exactly the edge of the dst reg.
Signed-off-by: Menglong Dong <menglong8.dong@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://lore.kernel.org/r/20231219134800.1550388-2-menglong8.dong@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
d17aff807f |
Revert BPF token-related functionality
This patch includes the following revert (one conflicting BPF FS patch and three token patch sets, represented by merge commits): - revert |
|
|
Jakub Kicinski
|
c49b292d03 |
netdev
-----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEE+soXsSLHKoYyzcli6rmadz2vbToFAmWAz2EACgkQ6rmadz2v bToqrw/9EwroZCc8GEHOKAlb/fzrMvn92rLo0ZW/cGN84QJPnx4zM6Zo0+fgLaaN oqqztwMUwdzGC3uX3FfVXaaLKbJ/MeHeL9BXFZNW8zkRHciw4R7kIBhOdPnHyET7 uT+rQ4xPe1Mt7e9PjepKlSL5mEsxWfBkdUgsdn19Z2Vjdfr9mZMhYWYMJGcfTCD1 TwxHKBPhq5fN3IsshmMBB8IrRp1HStUKb65MgZ4dI22LJXxTsFkx5XMFXcmuqvkH NhKj8jDcPEEh31bYcb6aG2Z4onw5F2lquygjk1Qyy5cyw45m/ipJKAXKdAyvJG+R VZCWOET/9wbRwFSK5wxwihCuKghFiofK52i2PcGtXZh0PCouyZZneSJOKM0yVWKO BvuJBxK4ETRnQyN6ZxhuJiEXG3/YMBBhyR2TX1LntVK9ct/k7qFVzATG49J39/sR SYMbptBRj4a5oMJ1qn0nFVEDFkg0jTnTDNnsEpcz60Ayt6EsJ1XosO5yz2huf861 xgRMTKMseyG1/uV45tQ8ZPzbSPpBxjUi9Dl3coYsIm1a+y6clWUXcarONY5KVrpS CR98DuFgl+E7dXuisd/Kz2p2KxxSPq8nytsmLlgOvrUqhwiXqB+TKN8EHgIapVOt l1A5LrzXFTcGlT9MlaWBqEIy83Bu1nqQqbxrAFOE0k8A5jomXaw= =stU2 -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Alexei Starovoitov says: ==================== pull-request: bpf-next 2023-12-18 This PR is larger than usual and contains changes in various parts of the kernel. The main changes are: 1) Fix kCFI bugs in BPF, from Peter Zijlstra. End result: all forms of indirect calls from BPF into kernel and from kernel into BPF work with CFI enabled. This allows BPF to work with CONFIG_FINEIBT=y. 2) Introduce BPF token object, from Andrii Nakryiko. It adds an ability to delegate a subset of BPF features from privileged daemon (e.g., systemd) through special mount options for userns-bound BPF FS to a trusted unprivileged application. The design accommodates suggestions from Christian Brauner and Paul Moore. Example: $ sudo mkdir -p /sys/fs/bpf/token $ sudo mount -t bpf bpffs /sys/fs/bpf/token \ -o delegate_cmds=prog_load:MAP_CREATE \ -o delegate_progs=kprobe \ -o delegate_attachs=xdp 3) Various verifier improvements and fixes, from Andrii Nakryiko, Andrei Matei. - Complete precision tracking support for register spills - Fix verification of possibly-zero-sized stack accesses - Fix access to uninit stack slots - Track aligned STACK_ZERO cases as imprecise spilled registers. It improves the verifier "instructions processed" metric from single digit to 50-60% for some programs. - Fix verifier retval logic 4) Support for VLAN tag in XDP hints, from Larysa Zaremba. 5) Allocate BPF trampoline via bpf_prog_pack mechanism, from Song Liu. End result: better memory utilization and lower I$ miss for calls to BPF via BPF trampoline. 6) Fix race between BPF prog accessing inner map and parallel delete, from Hou Tao. 7) Add bpf_xdp_get_xfrm_state() kfunc, from Daniel Xu. It allows BPF interact with IPSEC infra. The intent is to support software RSS (via XDP) for the upcoming ipsec pcpu work. Experiments on AWS demonstrate single tunnel pcpu ipsec reaching line rate on 100G ENA nics. 8) Expand bpf_cgrp_storage to support cgroup1 non-attach, from Yafang Shao. 9) BPF file verification via fsverity, from Song Liu. It allows BPF progs get fsverity digest. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (164 commits) bpf: Ensure precise is reset to false in __mark_reg_const_zero() selftests/bpf: Add more uprobe multi fail tests bpf: Fail uprobe multi link with negative offset selftests/bpf: Test the release of map btf s390/bpf: Fix indirect trampoline generation selftests/bpf: Temporarily disable dummy_struct_ops test on s390 x86/cfi,bpf: Fix bpf_exception_cb() signature bpf: Fix dtor CFI cfi: Add CFI_NOSEAL() x86/cfi,bpf: Fix bpf_struct_ops CFI x86/cfi,bpf: Fix bpf_callback_t CFI x86/cfi,bpf: Fix BPF JIT call cfi: Flip headers selftests/bpf: Add test for abnormal cnt during multi-kprobe attachment selftests/bpf: Don't use libbpf_get_error() in kprobe_multi_test selftests/bpf: Add test for abnormal cnt during multi-uprobe attachment bpf: Limit the number of kprobes when attaching program to multiple kprobes bpf: Limit the number of uprobes when attaching program to multiple uprobes bpf: xdp: Register generic_kfunc_set with XDP programs selftests/bpf: utilize string values for delegate_xxx mount options ... ==================== Link: https://lore.kernel.org/r/20231219000520.34178-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Andrii Nakryiko
|
8e432e6197 |
bpf: Ensure precise is reset to false in __mark_reg_const_zero()
It is safe to always start with imprecise SCALAR_VALUE register. Previously __mark_reg_const_zero() relied on caller to reset precise mark, but it's very error prone and we already missed it in a few places. So instead make __mark_reg_const_zero() reset precision always, as it's a safe default for SCALAR_VALUE. Explanation is basically the same as for why we are resetting (or rather not setting) precision in current state. If necessary, precision propagation will set it to precise correctly. As such, also remove a big comment about forward precision propagation in mark_reg_stack_read() and avoid unnecessarily setting precision to true after reading from STACK_ZERO stack. Again, precision propagation will correctly handle this, if that SCALAR_VALUE register will ever be needed to be precise. Reported-by: Maxim Mikityanskiy <maxtram95@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yonghong.song@linux.dev> Acked-by: Maxim Mikityanskiy <maxtram95@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20231218173601.53047-1-andrii@kernel.org |
|
Alexei Starovoitov
|
852486b35f |
x86/cfi,bpf: Fix bpf_exception_cb() signature
As per the earlier patches, BPF sub-programs have bpf_callback_t signature and CFI expects callers to have matching signature. This is violated by bpf_prog_aux::bpf_exception_cb(). [peterz: Changelog] Reported-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/CAADnVQ+Z7UcXXBBhMubhcMM=R-dExk-uHtfOLtoLxQ1XxEpqEA@mail.gmail.com Link: https://lore.kernel.org/r/20231215092707.910319166@infradead.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Peter Zijlstra
|
e4c0033989 |
bpf: Fix dtor CFI
Ensure the various dtor functions match their prototype and retain their CFI signatures, since they don't have their address taken, they are prone to not getting CFI, making them impossible to call indirectly. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20231215092707.799451071@infradead.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Peter Zijlstra
|
2cd3e3772e |
x86/cfi,bpf: Fix bpf_struct_ops CFI
BPF struct_ops uses __arch_prepare_bpf_trampoline() to write trampolines for indirect function calls. These tramplines much have matching CFI. In order to obtain the correct CFI hash for the various methods, add a matching structure that contains stub functions, the compiler will generate correct CFI which we can pilfer for the trampolines. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20231215092707.566977112@infradead.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Peter Zijlstra
|
4f9087f166 |
x86/cfi,bpf: Fix BPF JIT call
The current BPF call convention is __nocfi, except when it calls !JIT things, then it calls regular C functions. It so happens that with FineIBT the __nocfi and C calling conventions are incompatible. Specifically __nocfi will call at func+0, while FineIBT will have endbr-poison there, which is not a valid indirect target. Causing #CP. Notably this only triggers on IBT enabled hardware, which is probably why this hasn't been reported (also, most people will have JIT on anyway). Implement proper CFI prologues for the BPF JIT codegen and drop __nocfi for x86. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/r/20231215092707.345270396@infradead.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Daniel Xu
|
7489723c2e |
bpf: xdp: Register generic_kfunc_set with XDP programs
Registering generic_kfunc_set with XDP programs enables some of the newer BPF features inside XDP -- namely tree based data structures and BPF exceptions. The current motivation for this commit is to enable assertions inside XDP bpf progs. Assertions are a standard and useful tool to encode intent. Signed-off-by: Daniel Xu <dxu@dxuuu.xyz> Link: https://lore.kernel.org/r/d07d4614b81ca6aada44fcb89bb6b618fb66e4ca.1702594357.git.dxu@dxuuu.xyz Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
c5707b2146 |
bpf: support symbolic BPF FS delegation mount options
Besides already supported special "any" value and hex bit mask, support
string-based parsing of delegation masks based on exact enumerator
names. Utilize BTF information of `enum bpf_cmd`, `enum bpf_map_type`,
`enum bpf_prog_type`, and `enum bpf_attach_type` types to find supported
symbolic names (ignoring __MAX_xxx guard values and stripping repetitive
prefixes like BPF_ for cmd and attach types, BPF_MAP_TYPE_ for maps, and
BPF_PROG_TYPE_ for prog types). The case doesn't matter, but it is
normalized to lower case in mount option output. So "PROG_LOAD",
"prog_load", and "MAP_create" are all valid values to specify for
delegate_cmds options, "array" is among supported for map types, etc.
Besides supporting string values, we also support multiple values
specified at the same time, using colon (':') separator.
There are corresponding changes on bpf_show_options side to use known
values to print them in human-readable format, falling back to hex mask
printing, if there are any unrecognized bits. This shouldn't be
necessary when enum BTF information is present, but in general we should
always be able to fall back to this even if kernel was built without BTF.
As mentioned, emitted symbolic names are normalized to be all lower case.
Example below shows various ways to specify delegate_cmds options
through mount command and how mount options are printed back:
12/14 14:39:07.604
vmuser@archvm:~/local/linux/tools/testing/selftests/bpf
$ mount | rg token
$ sudo mkdir -p /sys/fs/bpf/token
$ sudo mount -t bpf bpffs /sys/fs/bpf/token \
-o delegate_cmds=prog_load:MAP_CREATE \
-o delegate_progs=kprobe \
-o delegate_attachs=xdp
$ mount | grep token
bpffs on /sys/fs/bpf/token type bpf (rw,relatime,delegate_cmds=map_create:prog_load,delegate_progs=kprobe,delegate_attachs=xdp)
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231214225016.1209867-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Yonghong Song
|
59e5791f59 |
bpf: Fix a race condition between btf_put() and map_free()
When running `./test_progs -j` in my local vm with latest kernel,
I once hit a kasan error like below:
[ 1887.184724] BUG: KASAN: slab-use-after-free in bpf_rb_root_free+0x1f8/0x2b0
[ 1887.185599] Read of size 4 at addr ffff888106806910 by task kworker/u12:2/2830
[ 1887.186498]
[ 1887.186712] CPU: 3 PID: 2830 Comm: kworker/u12:2 Tainted: G OEL 6.7.0-rc3-00699-g90679706d486-dirty #494
[ 1887.188034] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[ 1887.189618] Workqueue: events_unbound bpf_map_free_deferred
[ 1887.190341] Call Trace:
[ 1887.190666] <TASK>
[ 1887.190949] dump_stack_lvl+0xac/0xe0
[ 1887.191423] ? nf_tcp_handle_invalid+0x1b0/0x1b0
[ 1887.192019] ? panic+0x3c0/0x3c0
[ 1887.192449] print_report+0x14f/0x720
[ 1887.192930] ? preempt_count_sub+0x1c/0xd0
[ 1887.193459] ? __virt_addr_valid+0xac/0x120
[ 1887.194004] ? bpf_rb_root_free+0x1f8/0x2b0
[ 1887.194572] kasan_report+0xc3/0x100
[ 1887.195085] ? bpf_rb_root_free+0x1f8/0x2b0
[ 1887.195668] bpf_rb_root_free+0x1f8/0x2b0
[ 1887.196183] ? __bpf_obj_drop_impl+0xb0/0xb0
[ 1887.196736] ? preempt_count_sub+0x1c/0xd0
[ 1887.197270] ? preempt_count_sub+0x1c/0xd0
[ 1887.197802] ? _raw_spin_unlock+0x1f/0x40
[ 1887.198319] bpf_obj_free_fields+0x1d4/0x260
[ 1887.198883] array_map_free+0x1a3/0x260
[ 1887.199380] bpf_map_free_deferred+0x7b/0xe0
[ 1887.199943] process_scheduled_works+0x3a2/0x6c0
[ 1887.200549] worker_thread+0x633/0x890
[ 1887.201047] ? __kthread_parkme+0xd7/0xf0
[ 1887.201574] ? kthread+0x102/0x1d0
[ 1887.202020] kthread+0x1ab/0x1d0
[ 1887.202447] ? pr_cont_work+0x270/0x270
[ 1887.202954] ? kthread_blkcg+0x50/0x50
[ 1887.203444] ret_from_fork+0x34/0x50
[ 1887.203914] ? kthread_blkcg+0x50/0x50
[ 1887.204397] ret_from_fork_asm+0x11/0x20
[ 1887.204913] </TASK>
[ 1887.204913] </TASK>
[ 1887.205209]
[ 1887.205416] Allocated by task 2197:
[ 1887.205881] kasan_set_track+0x3f/0x60
[ 1887.206366] __kasan_kmalloc+0x6e/0x80
[ 1887.206856] __kmalloc+0xac/0x1a0
[ 1887.207293] btf_parse_fields+0xa15/0x1480
[ 1887.207836] btf_parse_struct_metas+0x566/0x670
[ 1887.208387] btf_new_fd+0x294/0x4d0
[ 1887.208851] __sys_bpf+0x4ba/0x600
[ 1887.209292] __x64_sys_bpf+0x41/0x50
[ 1887.209762] do_syscall_64+0x4c/0xf0
[ 1887.210222] entry_SYSCALL_64_after_hwframe+0x63/0x6b
[ 1887.210868]
[ 1887.211074] Freed by task 36:
[ 1887.211460] kasan_set_track+0x3f/0x60
[ 1887.211951] kasan_save_free_info+0x28/0x40
[ 1887.212485] ____kasan_slab_free+0x101/0x180
[ 1887.213027] __kmem_cache_free+0xe4/0x210
[ 1887.213514] btf_free+0x5b/0x130
[ 1887.213918] rcu_core+0x638/0xcc0
[ 1887.214347] __do_softirq+0x114/0x37e
The error happens at bpf_rb_root_free+0x1f8/0x2b0:
00000000000034c0 <bpf_rb_root_free>:
; {
34c0: f3 0f 1e fa endbr64
34c4: e8 00 00 00 00 callq 0x34c9 <bpf_rb_root_free+0x9>
34c9: 55 pushq %rbp
34ca: 48 89 e5 movq %rsp, %rbp
...
; if (rec && rec->refcount_off >= 0 &&
36aa: 4d 85 ed testq %r13, %r13
36ad: 74 a9 je 0x3658 <bpf_rb_root_free+0x198>
36af: 49 8d 7d 10 leaq 0x10(%r13), %rdi
36b3: e8 00 00 00 00 callq 0x36b8 <bpf_rb_root_free+0x1f8>
<==== kasan function
36b8: 45 8b 7d 10 movl 0x10(%r13), %r15d
<==== use-after-free load
36bc: 45 85 ff testl %r15d, %r15d
36bf: 78 8c js 0x364d <bpf_rb_root_free+0x18d>
So the problem is at rec->refcount_off in the above.
I did some source code analysis and find the reason.
CPU A CPU B
bpf_map_put:
...
btf_put with rcu callback
...
bpf_map_free_deferred
with system_unbound_wq
... ... ...
... btf_free_rcu: ...
... ... bpf_map_free_deferred:
... ...
... ---------> btf_struct_metas_free()
... | race condition ...
... ---------> map->ops->map_free()
...
... btf->struct_meta_tab = NULL
In the above, map_free() corresponds to array_map_free() and eventually
calling bpf_rb_root_free() which calls:
...
__bpf_obj_drop_impl(obj, field->graph_root.value_rec, false);
...
Here, 'value_rec' is assigned in btf_check_and_fixup_fields() with following code:
meta = btf_find_struct_meta(btf, btf_id);
if (!meta)
return -EFAULT;
rec->fields[i].graph_root.value_rec = meta->record;
So basically, 'value_rec' is a pointer to the record in struct_metas_tab.
And it is possible that that particular record has been freed by
btf_struct_metas_free() and hence we have a kasan error here.
Actually it is very hard to reproduce the failure with current bpf/bpf-next
code, I only got the above error once. To increase reproducibility, I added
a delay in bpf_map_free_deferred() to delay map->ops->map_free(), which
significantly increased reproducibility.
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 5e43ddd1b83f..aae5b5213e93 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -695,6 +695,7 @@ static void bpf_map_free_deferred(struct work_struct *work)
struct bpf_map *map = container_of(work, struct bpf_map, work);
struct btf_record *rec = map->record;
+ mdelay(100);
security_bpf_map_free(map);
bpf_map_release_memcg(map);
/* implementation dependent freeing */
Hao also provided test cases ([1]) for easily reproducing the above issue.
There are two ways to fix the issue, the v1 of the patch ([2]) moving
btf_put() after map_free callback, and the v5 of the patch ([3]) using
a kptr style fix which tries to get a btf reference during
map_check_btf(). Each approach has its pro and cons. The first approach
delays freeing btf while the second approach needs to acquire reference
depending on context which makes logic not very elegant and may
complicate things with future new data structures. Alexei
suggested in [4] going back to v1 which is what this patch
tries to do.
Rerun './test_progs -j' with the above mdelay() hack for a couple
of times and didn't observe the error for the above rb_root test cases.
Running Hou's test ([1]) is also successful.
[1] https://lore.kernel.org/bpf/20231207141500.917136-1-houtao@huaweicloud.com/
[2] v1: https://lore.kernel.org/bpf/20231204173946.3066377-1-yonghong.song@linux.dev/
[3] v5: https://lore.kernel.org/bpf/20231208041621.2968241-1-yonghong.song@linux.dev/
[4] v4: https://lore.kernel.org/bpf/CAADnVQJ3FiXUhZJwX_81sjZvSYYKCFB3BT6P8D59RS2Gu+0Z7g@mail.gmail.com/
Cc: Hou Tao <houtao@huaweicloud.com>
Fixes:
|
|
|
Hou Tao
|
dc68540913 |
bpf: Use GFP_KERNEL in bpf_event_entry_gen()
rcu_read_lock() is no longer held when invoking bpf_event_entry_gen() which is called by perf_event_fd_array_get_ptr(), so using GFP_KERNEL instead of GFP_ATOMIC to reduce the possibility of failures due to out-of-memory. Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231214043010.3458072-3-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Hou Tao
|
8f82583f95 |
bpf: Reduce the scope of rcu_read_lock when updating fd map
There is no rcu-read-lock requirement for ops->map_fd_get_ptr() or ops->map_fd_put_ptr(), so doesn't use rcu-read-lock for these two callbacks. For bpf_fd_array_map_update_elem(), accessing array->ptrs doesn't need rcu-read-lock because array->ptrs must still be allocated. For bpf_fd_htab_map_update_elem(), htab_map_update_elem() only requires rcu-read-lock to be held to avoid the WARN_ON_ONCE(), so only use rcu_read_lock() during the invocation of htab_map_update_elem(). Acked-by: Yonghong Song <yonghong.song@linux.dev> Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231214043010.3458072-2-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Hou Tao
|
2a0c6b41ee |
bpf: Update the comments in maybe_wait_bpf_programs()
Since commit
|
|
|
Matt Bobrowski
|
b13cddf633 |
bpf: add small subset of SECURITY_PATH hooks to BPF sleepable_lsm_hooks list
security_path_* based LSM hooks appear to be generally missing from the sleepable_lsm_hooks list. Initially add a small subset of them to the preexisting sleepable_lsm_hooks list so that sleepable BPF helpers like bpf_d_path() can be used from sleepable BPF LSM based programs. The security_path_* hooks added in this patch are similar to the security_inode_* counterparts that already exist in the sleepable_lsm_hooks list, and are called in roughly similar points and contexts. Presumably, making them OK to be also annotated as sleepable. Building a kernel with DEBUG_ATOMIC_SLEEP options enabled and running reasonable workloads stimulating activity that would be intercepted by such security hooks didn't show any splats. Notably, I haven't added all the security_path_* LSM hooks that are available as I don't need them at this point in time. Signed-off-by: Matt Bobrowski <mattbobrowski@google.com> Acked-by: KP Singh <kpsingh@kernel.org> Link: https://lore.kernel.org/r/ZXM3IHHXpNY9y82a@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
f5fdb51fb9 |
bpf: fail BPF_TOKEN_CREATE if no delegation option was set on BPF FS
It's quite confusing in practice when it's possible to successfully create a BPF token from BPF FS that didn't have any of delegate_xxx mount options set up. While it's not wrong, it's actually more meaningful to reject BPF_TOKEN_CREATE with specific error code (-ENOENT) to let user-space know that no token delegation is setup up. So, instead of creating empty BPF token that will be always ignored because it doesn't have any of the allow_xxx bits set, reject it with -ENOENT. If we ever need empty BPF token to be possible, we can support that with extra flag passed into BPF_TOKEN_CREATE. Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231213190842.3844987-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Jie Jiang
|
750e785796 |
bpf: Support uid and gid when mounting bpffs
Parse uid and gid in bpf_parse_param() so that they can be passed in as the `data` parameter when mount() bpffs. This will be useful when we want to control which user/group has the control to the mounted bpffs, otherwise a separate chown() call will be needed. Signed-off-by: Jie Jiang <jiejiang@chromium.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Mike Frysinger <vapier@chromium.org> Acked-by: Christian Brauner <brauner@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20231212093923.497838-1-jiejiang@chromium.org |
|
|
Andrei Matei
|
745e031130 |
bpf: Comment on check_mem_size_reg
This patch adds a comment to check_mem_size_reg -- a function whose meaning is not very transparent. The function implicitly deals with two registers connected by convention, which is not obvious. Signed-off-by: Andrei Matei <andreimatei1@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20231210225149.67639-1-andreimatei1@gmail.com |
|
Yang Li
|
56c26d5ad8 |
bpf: Remove unused backtrack_state helper functions
The function are defined in the verifier.c file, but not called elsewhere, so delete the unused function. kernel/bpf/verifier.c:3448:20: warning: unused function 'bt_set_slot' kernel/bpf/verifier.c:3453:20: warning: unused function 'bt_clear_slot' kernel/bpf/verifier.c:3488:20: warning: unused function 'bt_is_slot_set' Reported-by: Abaci Robot <abaci@linux.alibaba.com> Signed-off-by: Yang Li <yang.lee@linux.alibaba.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20231212005436.103829-1-yang.lee@linux.alibaba.com Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=7714 |
|
|
Andrii Nakryiko
|
1a1ad782dc |
bpf: tidy up exception callback management a bit
Use the fact that we are passing subprog index around and have a corresponding struct bpf_subprog_info in bpf_verifier_env for each subprogram. We don't need to separately pass around a flag whether subprog is exception callback or not, each relevant verifier function can determine this using provided subprog index if we maintain bpf_subprog_info properly. Also move out exception callback-specific logic from btf_prepare_func_args(), keeping it generic. We can enforce all these restriction right before exception callback verification pass. We add out parameter, arg_cnt, for now, but this will be unnecessary with subsequent refactoring and will be removed. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20231204233931.49758-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
22b769bb4f |
bpf: emit more dynptr information in verifier log
Emit dynptr type for CONST_PTR_TO_DYNPTR register. Also emit id, ref_obj_id, and dynptr_id fields for STACK_DYNPTR stack slots. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20231204233931.49758-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
1e68485d82 |
bpf: log PTR_TO_MEM memory size in verifier log
Emit valid memory size addressable through PTR_TO_MEM register. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20231204233931.49758-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
David Vernet
|
a6de18f310 |
bpf: Add bpf_cpumask_weight() kfunc
It can be useful to query how many bits are set in a cpumask. For example, if you want to perform special logic for the last remaining core that's set in a mask. Let's therefore add a new bpf_cpumask_weight() kfunc which checks how many bits are set in a mask. Signed-off-by: David Vernet <void@manifault.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20231207210843.168466-2-void@manifault.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
482d548d40 |
bpf: handle fake register spill to stack with BPF_ST_MEM instruction
When verifier validates BPF_ST_MEM instruction that stores known
constant to stack (e.g., *(u64 *)(r10 - 8) = 123), it effectively spills
a fake register with a constant (but initially imprecise) value to
a stack slot. Because read-side logic treats it as a proper register
fill from stack slot, we need to mark such stack slot initialization as
INSN_F_STACK_ACCESS instruction to stop precision backtracking from
missing it.
Fixes:
|
|
|
Hou Tao
|
06e5c999f1 |
bpf: Set uattr->batch.count as zero before batched update or deletion
generic_map_{delete,update}_batch() doesn't set uattr->batch.count as
zero before it tries to allocate memory for key. If the memory
allocation fails, the value of uattr->batch.count will be incorrect.
Fix it by setting uattr->batch.count as zero beore batched update or
deletion.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20231208102355.2628918-6-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Hou Tao
|
67ad2c73ff |
bpf: Only call maybe_wait_bpf_programs() when map operation succeeds
There is no need to call maybe_wait_bpf_programs() if update or deletion operation fails. So only call maybe_wait_bpf_programs() if update or deletion operation succeeds. Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231208102355.2628918-5-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Hou Tao
|
012772581d |
bpf: Add missed maybe_wait_bpf_programs() for htab of maps
When doing batched lookup and deletion operations on htab of maps,
maybe_wait_bpf_programs() is needed to ensure all programs don't use the
inner map after the bpf syscall returns.
Instead of adding the wait in __htab_map_lookup_and_delete_batch(),
adding the wait in bpf_map_do_batch() and also removing the calling of
maybe_wait_bpf_programs() from generic_map_{delete,update}_batch().
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20231208102355.2628918-4-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Hou Tao
|
37ba5b59d6 |
bpf: Call maybe_wait_bpf_programs() only once for generic_map_update_batch()
Just like commit
|
|
|
Hou Tao
|
c26f2a8901 |
bpf: Remove unnecessary wait from bpf_map_copy_value()
Both map_lookup_elem() and generic_map_lookup_batch() use
bpf_map_copy_value() to lookup and copy the value, and there is no
update operation in bpf_map_copy_value(), so just remove the invocation
of maybe_wait_bpf_programs() from it.
Fixes:
|
|
|
Yafang Shao
|
73d9eb340d |
bpf: Enable bpf_cgrp_storage for cgroup1 non-attach case
In the current cgroup1 environment, associating operations between cgroups and applications in a BPF program requires storing a mapping of cgroup_id to application either in a hash map or maintaining it in userspace. However, by enabling bpf_cgrp_storage for cgroup1, it becomes possible to conveniently store application-specific information in cgroup-local storage and utilize it within BPF programs. Furthermore, enabling this feature for cgroup1 involves minor modifications for the non-attach case, streamlining the process. However, when it comes to enabling this functionality for the cgroup1 attach case, it presents challenges. Therefore, the decision is to focus on enabling it solely for the cgroup1 non-attach case at present. If attempting to attach to a cgroup1 fd, the operation will simply fail with the error code -EBADF. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20231206115326.4295-2-laoar.shao@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> |
|
|
Andrei Matei
|
2929bfac00 |
bpf: Minor cleanup around stack bounds
Push the rounding up of stack offsets into the function responsible for growing the stack, rather than relying on all the callers to do it. Uncertainty about whether the callers did it or not tripped up people in a previous review. Signed-off-by: Andrei Matei <andreimatei1@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/bpf/20231208032519.260451-4-andreimatei1@gmail.com |
|
|
Andrei Matei
|
6b4a64bafd |
bpf: Fix accesses to uninit stack slots
Privileged programs are supposed to be able to read uninitialized stack memory (ever since |
|
|
Jakub Kicinski
|
2483e7f04c |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/ethernet/stmicro/stmmac/dwmac5.c drivers/net/ethernet/stmicro/stmmac/dwmac5.h drivers/net/ethernet/stmicro/stmmac/dwxgmac2_core.c drivers/net/ethernet/stmicro/stmmac/hwif.h |
|
|
Andrei Matei
|
1d38a9ee81 |
bpf: Guard stack limits against 32bit overflow
This patch promotes the arithmetic around checking stack bounds to be done in the 64-bit domain, instead of the current 32bit. The arithmetic implies adding together a 64-bit register with a int offset. The register was checked to be below 1<<29 when it was variable, but not when it was fixed. The offset either comes from an instruction (in which case it is 16 bit), from another register (in which case the caller checked it to be below 1<<29 [1]), or from the size of an argument to a kfunc (in which case it can be a u32 [2]). Between the register being inconsistently checked to be below 1<<29, and the offset being up to an u32, it appears that we were open to overflowing the `int`s which were currently used for arithmetic. [1] |
|
|
Andrei Matei
|
a833a17aea |
bpf: Fix verification of indirect var-off stack access
This patch fixes a bug around the verification of possibly-zero-sized
stack accesses. When the access was done through a var-offset stack
pointer, check_stack_access_within_bounds was incorrectly computing the
maximum-offset of a zero-sized read to be the same as the register's min
offset. Instead, we have to take in account the register's maximum
possible value. The patch also simplifies how the max offset is checked;
the check is now simpler than for min offset.
The bug was allowing accesses to erroneously pass the
check_stack_access_within_bounds() checks, only to later crash in
check_stack_range_initialized() when all the possibly-affected stack
slots are iterated (this time with a correct max offset).
check_stack_range_initialized() is relying on
check_stack_access_within_bounds() for its accesses to the
stack-tracking vector to be within bounds; in the case of zero-sized
accesses, we were essentially only verifying that the lowest possible
slot was within bounds. We would crash when the max-offset of the stack
pointer was >= 0 (which shouldn't pass verification, and hopefully is
not something anyone's code attempts to do in practice).
Thanks Hao for reporting!
Fixes:
|
|
Song Liu
|
26ef208c20 |
bpf: Use arch_bpf_trampoline_size
Instead of blindly allocating PAGE_SIZE for each trampoline, check the size of the trampoline with arch_bpf_trampoline_size(). This size is saved in bpf_tramp_image->size, and used for modmem charge/uncharge. The fallback arch_alloc_bpf_trampoline() still allocates a whole page because we need to use set_memory_* to protect the memory. struct_ops trampoline still uses a whole page for multiple trampolines. With this size check at caller (regular trampoline and struct_ops trampoline), remove arch_bpf_trampoline_size() from arch_prepare_bpf_trampoline() in archs. Also, update bpf_image_ksym_add() to handle symbol of different sizes. Signed-off-by: Song Liu <song@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # on s390x Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Björn Töpel <bjorn@rivosinc.com> Tested-by: Björn Töpel <bjorn@rivosinc.com> # on riscv Link: https://lore.kernel.org/r/20231206224054.492250-7-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Song Liu
|
96d1b7c081 |
bpf: Add arch_bpf_trampoline_size()
This helper will be used to calculate the size of the trampoline before allocating the memory. arch_prepare_bpf_trampoline() for arm64 and riscv64 can use arch_bpf_trampoline_size() to check the trampoline fits in the image. OTOH, arch_prepare_bpf_trampoline() for s390 has to call the JIT process twice, so it cannot use arch_bpf_trampoline_size(). Signed-off-by: Song Liu <song@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # on s390x Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Björn Töpel <bjorn@rivosinc.com> Tested-by: Björn Töpel <bjorn@rivosinc.com> # on riscv Link: https://lore.kernel.org/r/20231206224054.492250-6-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Song Liu
|
82583daa2e |
bpf: Add helpers for trampoline image management
As BPF trampoline of different archs moves from bpf_jit_[alloc|free]_exec() to bpf_prog_pack_[alloc|free](), we need to use different _alloc, _free for different archs during the transition. Add the following helpers for this transition: void *arch_alloc_bpf_trampoline(unsigned int size); void arch_free_bpf_trampoline(void *image, unsigned int size); void arch_protect_bpf_trampoline(void *image, unsigned int size); void arch_unprotect_bpf_trampoline(void *image, unsigned int size); The fallback version of these helpers require size <= PAGE_SIZE, but they are only called with size == PAGE_SIZE. They will be called with size < PAGE_SIZE when arch_bpf_trampoline_size() helper is introduced later. Signed-off-by: Song Liu <song@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # on s390x Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20231206224054.492250-4-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Song Liu
|
7a3d9a159b |
bpf: Adjust argument names of arch_prepare_bpf_trampoline()
We are using "im" for "struct bpf_tramp_image" and "tr" for "struct bpf_trampoline" in most of the code base. The only exception is the prototype and fallback version of arch_prepare_bpf_trampoline(). Update them to match the rest of the code base. We mix "orig_call" and "func_addr" for the argument in different versions of arch_prepare_bpf_trampoline(). s/orig_call/func_addr/g so they match. Signed-off-by: Song Liu <song@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # on s390x Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20231206224054.492250-3-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Song Liu
|
f08a1c6582 |
bpf: Let bpf_prog_pack_free handle any pointer
Currently, bpf_prog_pack_free only can only free pointer to struct bpf_binary_header, which is not flexible. Add a size argument to bpf_prog_pack_free so that it can handle any pointer. Signed-off-by: Song Liu <song@kernel.org> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Tested-by: Ilya Leoshkevich <iii@linux.ibm.com> # on s390x Reviewed-by: Björn Töpel <bjorn@rivosinc.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20231206224054.492250-2-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jiri Olsa
|
4b7de80160 |
bpf: Fix prog_array_map_poke_run map poke update
Lee pointed out issue found by syscaller [0] hitting BUG in prog array
map poke update in prog_array_map_poke_run function due to error value
returned from bpf_arch_text_poke function.
There's race window where bpf_arch_text_poke can fail due to missing
bpf program kallsym symbols, which is accounted for with check for
-EINVAL in that BUG_ON call.
The problem is that in such case we won't update the tail call jump
and cause imbalance for the next tail call update check which will
fail with -EBUSY in bpf_arch_text_poke.
I'm hitting following race during the program load:
CPU 0 CPU 1
bpf_prog_load
bpf_check
do_misc_fixups
prog_array_map_poke_track
map_update_elem
bpf_fd_array_map_update_elem
prog_array_map_poke_run
bpf_arch_text_poke returns -EINVAL
bpf_prog_kallsyms_add
After bpf_arch_text_poke (CPU 1) fails to update the tail call jump, the next
poke update fails on expected jump instruction check in bpf_arch_text_poke
with -EBUSY and triggers the BUG_ON in prog_array_map_poke_run.
Similar race exists on the program unload.
Fixing this by moving the update to bpf_arch_poke_desc_update function which
makes sure we call __bpf_arch_text_poke that skips the bpf address check.
Each architecture has slightly different approach wrt looking up bpf address
in bpf_arch_text_poke, so instead of splitting the function or adding new
'checkip' argument in previous version, it seems best to move the whole
map_poke_run update as arch specific code.
[0] https://syzkaller.appspot.com/bug?extid=97a4fe20470e9bc30810
Fixes:
|
|
|
Andrii Nakryiko
|
d734ca7b33 |
bpf,lsm: add BPF token LSM hooks
Wire up bpf_token_create and bpf_token_free LSM hooks, which allow to allocate LSM security blob (we add `void *security` field to struct bpf_token for that), but also control who can instantiate BPF token. This follows existing pattern for BPF map and BPF prog. Also add security_bpf_token_allow_cmd() and security_bpf_token_capable() LSM hooks that allow LSM implementation to control and negate (if necessary) BPF token's delegation of a specific bpf_cmd and capability, respectively. Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-12-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
66d636d70a |
bpf,lsm: refactor bpf_map_alloc/bpf_map_free LSM hooks
Similarly to bpf_prog_alloc LSM hook, rename and extend bpf_map_alloc hook into bpf_map_create, taking not just struct bpf_map, but also bpf_attr and bpf_token, to give a fuller context to LSMs. Unlike bpf_prog_alloc, there is no need to move the hook around, as it currently is firing right before allocating BPF map ID and FD, which seems to be a sweet spot. But like bpf_prog_alloc/bpf_prog_free combo, make sure that bpf_map_free LSM hook is called even if bpf_map_create hook returned error, as if few LSMs are combined together it could be that one LSM successfully allocated security blob for its needs, while subsequent LSM rejected BPF map creation. The former LSM would still need to free up LSM blob, so we need to ensure security_bpf_map_free() is called regardless of the outcome. Acked-by: Paul Moore <paul@paul-moore.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-11-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
c3dd6e94df |
bpf,lsm: refactor bpf_prog_alloc/bpf_prog_free LSM hooks
Based on upstream discussion ([0]), rework existing
bpf_prog_alloc_security LSM hook. Rename it to bpf_prog_load and instead
of passing bpf_prog_aux, pass proper bpf_prog pointer for a full BPF
program struct. Also, we pass bpf_attr union with all the user-provided
arguments for BPF_PROG_LOAD command. This will give LSMs as much
information as we can basically provide.
The hook is also BPF token-aware now, and optional bpf_token struct is
passed as a third argument. bpf_prog_load LSM hook is called after
a bunch of sanity checks were performed, bpf_prog and bpf_prog_aux were
allocated and filled out, but right before performing full-fledged BPF
verification step.
bpf_prog_free LSM hook is now accepting struct bpf_prog argument, for
consistency. SELinux code is adjusted to all new names, types, and
signatures.
Note, given that bpf_prog_load (previously bpf_prog_alloc) hook can be
used by some LSMs to allocate extra security blob, but also by other
LSMs to reject BPF program loading, we need to make sure that
bpf_prog_free LSM hook is called after bpf_prog_load/bpf_prog_alloc one
*even* if the hook itself returned error. If we don't do that, we run
the risk of leaking memory. This seems to be possible today when
combining SELinux and BPF LSM, as one example, depending on their
relative ordering.
Also, for BPF LSM setup, add bpf_prog_load and bpf_prog_free to
sleepable LSM hooks list, as they are both executed in sleepable
context. Also drop bpf_prog_load hook from untrusted, as there is no
issue with refcount or anything else anymore, that originally forced us
to add it to untrusted list in
|
|
|
Andrii Nakryiko
|
8062fb12de |
bpf: consistently use BPF token throughout BPF verifier logic
Remove remaining direct queries to perfmon_capable() and bpf_capable() in BPF verifier logic and instead use BPF token (if available) to make decisions about privileges. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-9-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
4cbb270e11 |
bpf: take into account BPF token when fetching helper protos
Instead of performing unconditional system-wide bpf_capable() and perfmon_capable() calls inside bpf_base_func_proto() function (and other similar ones) to determine eligibility of a given BPF helper for a given program, use previously recorded BPF token during BPF_PROG_LOAD command handling to inform the decision. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-8-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
e1cef620f5 |
bpf: add BPF token support to BPF_PROG_LOAD command
Add basic support of BPF token to BPF_PROG_LOAD. Wire through a set of allowed BPF program types and attach types, derived from BPF FS at BPF token creation time. Then make sure we perform bpf_token_capable() checks everywhere where it's relevant. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
ee54b1a910 |
bpf: add BPF token support to BPF_BTF_LOAD command
Accept BPF token FD in BPF_BTF_LOAD command to allow BTF data loading through delegated BPF token. BTF loading is a pretty straightforward operation, so as long as BPF token is created with allow_cmds granting BPF_BTF_LOAD command, kernel proceeds to parsing BTF data and creating BTF object. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
688b7270b3 |
bpf: add BPF token support to BPF_MAP_CREATE command
Allow providing token_fd for BPF_MAP_CREATE command to allow controlled BPF map creation from unprivileged process through delegated BPF token. Wire through a set of allowed BPF map types to BPF token, derived from BPF FS at BPF token creation time. This, in combination with allowed_cmds allows to create a narrowly-focused BPF token (controlled by privileged agent) with a restrictive set of BPF maps that application can attempt to create. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
4527358b76 |
bpf: introduce BPF token object
Add new kind of BPF kernel object, BPF token. BPF token is meant to
allow delegating privileged BPF functionality, like loading a BPF
program or creating a BPF map, from privileged process to a *trusted*
unprivileged process, all while having a good amount of control over which
privileged operations could be performed using provided BPF token.
This is achieved through mounting BPF FS instance with extra delegation
mount options, which determine what operations are delegatable, and also
constraining it to the owning user namespace (as mentioned in the
previous patch).
BPF token itself is just a derivative from BPF FS and can be created
through a new bpf() syscall command, BPF_TOKEN_CREATE, which accepts BPF
FS FD, which can be attained through open() API by opening BPF FS mount
point. Currently, BPF token "inherits" delegated command, map types,
prog type, and attach type bit sets from BPF FS as is. In the future,
having an BPF token as a separate object with its own FD, we can allow
to further restrict BPF token's allowable set of things either at the
creation time or after the fact, allowing the process to guard itself
further from unintentionally trying to load undesired kind of BPF
programs. But for now we keep things simple and just copy bit sets as is.
When BPF token is created from BPF FS mount, we take reference to the
BPF super block's owning user namespace, and then use that namespace for
checking all the {CAP_BPF, CAP_PERFMON, CAP_NET_ADMIN, CAP_SYS_ADMIN}
capabilities that are normally only checked against init userns (using
capable()), but now we check them using ns_capable() instead (if BPF
token is provided). See bpf_token_capable() for details.
Such setup means that BPF token in itself is not sufficient to grant BPF
functionality. User namespaced process has to *also* have necessary
combination of capabilities inside that user namespace. So while
previously CAP_BPF was useless when granted within user namespace, now
it gains a meaning and allows container managers and sys admins to have
a flexible control over which processes can and need to use BPF
functionality within the user namespace (i.e., container in practice).
And BPF FS delegation mount options and derived BPF tokens serve as
a per-container "flag" to grant overall ability to use bpf() (plus further
restrict on which parts of bpf() syscalls are treated as namespaced).
Note also, BPF_TOKEN_CREATE command itself requires ns_capable(CAP_BPF)
within the BPF FS owning user namespace, rounding up the ns_capable()
story of BPF token.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231130185229.2688956-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
40bba140c6 |
bpf: add BPF token delegation mount options to BPF FS
Add few new mount options to BPF FS that allow to specify that a given
BPF FS instance allows creation of BPF token (added in the next patch),
and what sort of operations are allowed under BPF token. As such, we get
4 new mount options, each is a bit mask
- `delegate_cmds` allow to specify which bpf() syscall commands are
allowed with BPF token derived from this BPF FS instance;
- if BPF_MAP_CREATE command is allowed, `delegate_maps` specifies
a set of allowable BPF map types that could be created with BPF token;
- if BPF_PROG_LOAD command is allowed, `delegate_progs` specifies
a set of allowable BPF program types that could be loaded with BPF token;
- if BPF_PROG_LOAD command is allowed, `delegate_attachs` specifies
a set of allowable BPF program attach types that could be loaded with
BPF token; delegate_progs and delegate_attachs are meant to be used
together, as full BPF program type is, in general, determined
through both program type and program attach type.
Currently, these mount options accept the following forms of values:
- a special value "any", that enables all possible values of a given
bit set;
- numeric value (decimal or hexadecimal, determined by kernel
automatically) that specifies a bit mask value directly;
- all the values for a given mount option are combined, if specified
multiple times. E.g., `mount -t bpf nodev /path/to/mount -o
delegate_maps=0x1 -o delegate_maps=0x2` will result in a combined 0x3
mask.
Ideally, more convenient (for humans) symbolic form derived from
corresponding UAPI enums would be accepted (e.g., `-o
delegate_progs=kprobe|tracepoint`) and I intend to implement this, but
it requires a bunch of UAPI header churn, so I postponed it until this
feature lands upstream or at least there is a definite consensus that
this feature is acceptable and is going to make it, just to minimize
amount of wasted effort and not increase amount of non-essential code to
be reviewed.
Attentive reader will notice that BPF FS is now marked as
FS_USERNS_MOUNT, which theoretically makes it mountable inside non-init
user namespace as long as the process has sufficient *namespaced*
capabilities within that user namespace. But in reality we still
restrict BPF FS to be mountable only by processes with CAP_SYS_ADMIN *in
init userns* (extra check in bpf_fill_super()). FS_USERNS_MOUNT is added
to allow creating BPF FS context object (i.e., fsopen("bpf")) from
inside unprivileged process inside non-init userns, to capture that
userns as the owning userns. It will still be required to pass this
context object back to privileged process to instantiate and mount it.
This manipulation is important, because capturing non-init userns as the
owning userns of BPF FS instance (super block) allows to use that userns
to constraint BPF token to that userns later on (see next patch). So
creating BPF FS with delegation inside unprivileged userns will restrict
derived BPF token objects to only "work" inside that intended userns,
making it scoped to a intended "container". Also, setting these
delegation options requires capable(CAP_SYS_ADMIN), so unprivileged
process cannot set this up without involvement of a privileged process.
There is a set of selftests at the end of the patch set that simulates
this sequence of steps and validates that everything works as intended.
But careful review is requested to make sure there are no missed gaps in
the implementation and testing.
This somewhat subtle set of aspects is the result of previous
discussions ([0]) about various user namespace implications and
interactions with BPF token functionality and is necessary to contain
BPF token inside intended user namespace.
[0] https://lore.kernel.org/bpf/20230704-hochverdient-lehne-eeb9eeef785e@brauner/
Acked-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231130185229.2688956-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
909fa05dd3 |
bpf: align CAP_NET_ADMIN checks with bpf_capable() approach
Within BPF syscall handling code CAP_NET_ADMIN checks stand out a bit compared to CAP_BPF and CAP_PERFMON checks. For the latter, CAP_BPF or CAP_PERFMON are checked first, but if they are not set, CAP_SYS_ADMIN takes over and grants whatever part of BPF syscall is required. Similar kind of checks that involve CAP_NET_ADMIN are not so consistent. One out of four uses does follow CAP_BPF/CAP_PERFMON model: during BPF_PROG_LOAD, if the type of BPF program is "network-related" either CAP_NET_ADMIN or CAP_SYS_ADMIN is required to proceed. But in three other cases CAP_NET_ADMIN is required even if CAP_SYS_ADMIN is set: - when creating DEVMAP/XDKMAP/CPU_MAP maps; - when attaching CGROUP_SKB programs; - when handling BPF_PROG_QUERY command. This patch is changing the latter three cases to follow BPF_PROG_LOAD model, that is allowing to proceed under either CAP_NET_ADMIN or CAP_SYS_ADMIN. This also makes it cleaner in subsequent BPF token patches to switch wholesomely to a generic bpf_token_capable(int cap) check, that always falls back to CAP_SYS_ADMIN if requested capability is missing. Cc: Jakub Kicinski <kuba@kernel.org> Acked-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231130185229.2688956-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
18a433b620 |
bpf: track aligned STACK_ZERO cases as imprecise spilled registers
Now that precision backtracing is supporting register spill/fill to/from
stack, there is another oportunity to be exploited here: minimizing
precise STACK_ZERO cases. With a simple code change we can rely on
initially imprecise register spill tracking for cases when register
spilled to stack was a known zero.
This is a very common case for initializing on the stack variables,
including rather large structures. Often times zero has no special
meaning for the subsequent BPF program logic and is often overwritten
with non-zero values soon afterwards. But due to STACK_ZERO vs
STACK_MISC tracking, such initial zero initialization actually causes
duplication of verifier states as STACK_ZERO is clearly different than
STACK_MISC or spilled SCALAR_VALUE register.
The effect of this (now) trivial change is huge, as can be seen below.
These are differences between BPF selftests, Cilium, and Meta-internal
BPF object files relative to previous patch in this series. You can see
improvements ranging from single-digit percentage improvement for
instructions and states, all the way to 50-60% reduction for some of
Meta-internal host agent programs, and even some Cilium programs.
For Meta-internal ones I left only the differences for largest BPF
object files by states/instructions, as there were too many differences
in the overall output. All the differences were improvements, reducting
number of states and thus instructions validated.
Note, Meta-internal BPF object file names are not printed below.
Many copies of balancer_ingress are actually many different
configurations of Katran, so they are different BPF programs, which
explains state reduction going from -16% all the way to 31%, depending
on BPF program logic complexity.
I also tooked a closer look at a few small-ish BPF programs to validate
the behavior. Let's take bpf_iter_netrlink.bpf.o (first row below).
While it's just 8 vs 5 states, verifier log is still pretty long to
include it here. But the reduction in states is due to the following
piece of C code:
unsigned long ino;
...
sk = s->sk_socket;
if (!sk) {
ino = 0;
} else {
inode = SOCK_INODE(sk);
bpf_probe_read_kernel(&ino, sizeof(ino), &inode->i_ino);
}
BPF_SEQ_PRINTF(seq, "%-8u %-8lu\n", s->sk_drops.counter, ino);
return 0;
You can see that in some situations `ino` is zero-initialized, while in
others it's unknown value filled out by bpf_probe_read_kernel(). Before
this change code after if/else branches have to be validated twice. Once
with (precise) ino == 0, due to eager STACK_ZERO logic, and then again
for when ino is just STACK_MISC. But BPF_SEQ_PRINTF() doesn't care about
precise value of ino, so with the change in this patch verifier is able
to prune states from after one of the branches, reducing number of total
states (and instructions) required for successful validation.
Similar principle applies to bigger real-world applications, just at
a much larger scale.
SELFTESTS
=========
File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF)
--------------------------------------- ----------------------- --------- --------- --------------- ---------- ---------- -------------
bpf_iter_netlink.bpf.linked3.o dump_netlink 148 104 -44 (-29.73%) 8 5 -3 (-37.50%)
bpf_iter_unix.bpf.linked3.o dump_unix 8474 8404 -70 (-0.83%) 151 147 -4 (-2.65%)
bpf_loop.bpf.linked3.o stack_check 560 324 -236 (-42.14%) 42 24 -18 (-42.86%)
local_storage_bench.bpf.linked3.o get_local 120 77 -43 (-35.83%) 9 6 -3 (-33.33%)
loop6.bpf.linked3.o trace_virtqueue_add_sgs 10167 9868 -299 (-2.94%) 226 206 -20 (-8.85%)
pyperf600_bpf_loop.bpf.linked3.o on_event 4872 3423 -1449 (-29.74%) 322 229 -93 (-28.88%)
strobemeta.bpf.linked3.o on_event 180697 176036 -4661 (-2.58%) 4780 4734 -46 (-0.96%)
test_cls_redirect.bpf.linked3.o cls_redirect 65594 65401 -193 (-0.29%) 4230 4212 -18 (-0.43%)
test_global_func_args.bpf.linked3.o test_cls 145 136 -9 (-6.21%) 10 9 -1 (-10.00%)
test_l4lb.bpf.linked3.o balancer_ingress 4760 2612 -2148 (-45.13%) 113 102 -11 (-9.73%)
test_l4lb_noinline.bpf.linked3.o balancer_ingress 4845 4877 +32 (+0.66%) 219 221 +2 (+0.91%)
test_l4lb_noinline_dynptr.bpf.linked3.o balancer_ingress 2072 2087 +15 (+0.72%) 97 98 +1 (+1.03%)
test_seg6_loop.bpf.linked3.o __add_egr_x 12440 9975 -2465 (-19.82%) 364 353 -11 (-3.02%)
test_tcp_hdr_options.bpf.linked3.o estab 2558 2572 +14 (+0.55%) 179 180 +1 (+0.56%)
test_xdp_dynptr.bpf.linked3.o _xdp_tx_iptunnel 645 596 -49 (-7.60%) 26 24 -2 (-7.69%)
test_xdp_noinline.bpf.linked3.o balancer_ingress_v6 3520 3516 -4 (-0.11%) 216 216 +0 (+0.00%)
xdp_synproxy_kern.bpf.linked3.o syncookie_tc 82661 81241 -1420 (-1.72%) 5073 5155 +82 (+1.62%)
xdp_synproxy_kern.bpf.linked3.o syncookie_xdp 84964 82297 -2667 (-3.14%) 5130 5157 +27 (+0.53%)
META-INTERNAL
=============
Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF)
-------------------------------------- --------- --------- ----------------- ---------- ---------- ---------------
balancer_ingress 27925 23608 -4317 (-15.46%) 1488 1482 -6 (-0.40%)
balancer_ingress 31824 27546 -4278 (-13.44%) 1658 1652 -6 (-0.36%)
balancer_ingress 32213 27935 -4278 (-13.28%) 1689 1683 -6 (-0.36%)
balancer_ingress 32213 27935 -4278 (-13.28%) 1689 1683 -6 (-0.36%)
balancer_ingress 31824 27546 -4278 (-13.44%) 1658 1652 -6 (-0.36%)
balancer_ingress 38647 29562 -9085 (-23.51%) 2069 1835 -234 (-11.31%)
balancer_ingress 38647 29562 -9085 (-23.51%) 2069 1835 -234 (-11.31%)
balancer_ingress 40339 30792 -9547 (-23.67%) 2193 1934 -259 (-11.81%)
balancer_ingress 37321 29055 -8266 (-22.15%) 1972 1795 -177 (-8.98%)
balancer_ingress 38176 29753 -8423 (-22.06%) 2008 1831 -177 (-8.81%)
balancer_ingress 29193 20910 -8283 (-28.37%) 1599 1422 -177 (-11.07%)
balancer_ingress 30013 21452 -8561 (-28.52%) 1645 1447 -198 (-12.04%)
balancer_ingress 28691 24290 -4401 (-15.34%) 1545 1531 -14 (-0.91%)
balancer_ingress 34223 28965 -5258 (-15.36%) 1984 1875 -109 (-5.49%)
balancer_ingress 35481 26158 -9323 (-26.28%) 2095 1806 -289 (-13.79%)
balancer_ingress 35481 26158 -9323 (-26.28%) 2095 1806 -289 (-13.79%)
balancer_ingress 35868 26455 -9413 (-26.24%) 2140 1827 -313 (-14.63%)
balancer_ingress 35868 26455 -9413 (-26.24%) 2140 1827 -313 (-14.63%)
balancer_ingress 35481 26158 -9323 (-26.28%) 2095 1806 -289 (-13.79%)
balancer_ingress 35481 26158 -9323 (-26.28%) 2095 1806 -289 (-13.79%)
balancer_ingress 34844 29485 -5359 (-15.38%) 2036 1918 -118 (-5.80%)
fbflow_egress 3256 2652 -604 (-18.55%) 218 192 -26 (-11.93%)
fbflow_ingress 1026 944 -82 (-7.99%) 70 63 -7 (-10.00%)
sslwall_tc_egress 8424 7360 -1064 (-12.63%) 498 458 -40 (-8.03%)
syar_accept_protect 15040 9539 -5501 (-36.58%) 364 220 -144 (-39.56%)
syar_connect_tcp_v6 15036 9535 -5501 (-36.59%) 360 216 -144 (-40.00%)
syar_connect_udp_v4 15039 9538 -5501 (-36.58%) 361 217 -144 (-39.89%)
syar_connect_connect4_protect4 24805 15833 -8972 (-36.17%) 756 480 -276 (-36.51%)
syar_lsm_file_open 167772 151813 -15959 (-9.51%) 1836 1667 -169 (-9.20%)
syar_namespace_create_new 14805 9304 -5501 (-37.16%) 353 209 -144 (-40.79%)
syar_python3_detect 17531 12030 -5501 (-31.38%) 391 247 -144 (-36.83%)
syar_ssh_post_fork 16412 10911 -5501 (-33.52%) 405 261 -144 (-35.56%)
syar_enter_execve 14728 9227 -5501 (-37.35%) 345 201 -144 (-41.74%)
syar_enter_execveat 14728 9227 -5501 (-37.35%) 345 201 -144 (-41.74%)
syar_exit_execve 16622 11121 -5501 (-33.09%) 376 232 -144 (-38.30%)
syar_exit_execveat 16622 11121 -5501 (-33.09%) 376 232 -144 (-38.30%)
syar_syscalls_kill 15288 9787 -5501 (-35.98%) 398 254 -144 (-36.18%)
syar_task_enter_pivot_root 14898 9397 -5501 (-36.92%) 357 213 -144 (-40.34%)
syar_syscalls_setreuid 16678 11177 -5501 (-32.98%) 429 285 -144 (-33.57%)
syar_syscalls_setuid 16678 11177 -5501 (-32.98%) 429 285 -144 (-33.57%)
syar_syscalls_process_vm_readv 14959 9458 -5501 (-36.77%) 364 220 -144 (-39.56%)
syar_syscalls_process_vm_writev 15757 10256 -5501 (-34.91%) 390 246 -144 (-36.92%)
do_uprobe 15519 10018 -5501 (-35.45%) 373 229 -144 (-38.61%)
edgewall 179715 55783 -123932 (-68.96%) 12607 3999 -8608 (-68.28%)
bictcp_state 7570 4131 -3439 (-45.43%) 496 269 -227 (-45.77%)
cubictcp_state 7570 4131 -3439 (-45.43%) 496 269 -227 (-45.77%)
tcp_rate_skb_delivered 447 272 -175 (-39.15%) 29 18 -11 (-37.93%)
kprobe__bbr_set_state 4566 2615 -1951 (-42.73%) 209 124 -85 (-40.67%)
kprobe__bictcp_state 4566 2615 -1951 (-42.73%) 209 124 -85 (-40.67%)
inet_sock_set_state 1501 1337 -164 (-10.93%) 93 85 -8 (-8.60%)
tcp_retransmit_skb 1145 981 -164 (-14.32%) 67 59 -8 (-11.94%)
tcp_retransmit_synack 1183 951 -232 (-19.61%) 67 55 -12 (-17.91%)
bpf_tcptuner 1459 1187 -272 (-18.64%) 99 80 -19 (-19.19%)
tw_egress 801 776 -25 (-3.12%) 69 66 -3 (-4.35%)
tw_ingress 795 770 -25 (-3.14%) 69 66 -3 (-4.35%)
ttls_tc_ingress 19025 19383 +358 (+1.88%) 470 465 -5 (-1.06%)
ttls_nat_egress 490 299 -191 (-38.98%) 33 20 -13 (-39.39%)
ttls_nat_ingress 448 285 -163 (-36.38%) 32 21 -11 (-34.38%)
tw_twfw_egress 511127 212071 -299056 (-58.51%) 16733 8504 -8229 (-49.18%)
tw_twfw_ingress 500095 212069 -288026 (-57.59%) 16223 8504 -7719 (-47.58%)
tw_twfw_tc_eg 511113 212064 -299049 (-58.51%) 16732 8504 -8228 (-49.18%)
tw_twfw_tc_in 500095 212069 -288026 (-57.59%) 16223 8504 -7719 (-47.58%)
tw_twfw_egress 12632 12435 -197 (-1.56%) 276 260 -16 (-5.80%)
tw_twfw_ingress 12631 12454 -177 (-1.40%) 278 261 -17 (-6.12%)
tw_twfw_tc_eg 12595 12435 -160 (-1.27%) 274 259 -15 (-5.47%)
tw_twfw_tc_in 12631 12454 -177 (-1.40%) 278 261 -17 (-6.12%)
tw_xdp_dump 266 209 -57 (-21.43%) 9 8 -1 (-11.11%)
CILIUM
=========
File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF)
------------- -------------------------------- --------- --------- ---------------- ---------- ---------- --------------
bpf_host.o cil_to_netdev 6047 4578 -1469 (-24.29%) 362 249 -113 (-31.22%)
bpf_host.o handle_lxc_traffic 2227 1585 -642 (-28.83%) 156 103 -53 (-33.97%)
bpf_host.o tail_handle_ipv4_from_netdev 2244 1458 -786 (-35.03%) 163 106 -57 (-34.97%)
bpf_host.o tail_handle_nat_fwd_ipv4 21022 10479 -10543 (-50.15%) 1289 670 -619 (-48.02%)
bpf_host.o tail_handle_nat_fwd_ipv6 15433 11375 -4058 (-26.29%) 905 643 -262 (-28.95%)
bpf_host.o tail_ipv4_host_policy_ingress 2219 1367 -852 (-38.40%) 161 96 -65 (-40.37%)
bpf_host.o tail_nodeport_nat_egress_ipv4 22460 19862 -2598 (-11.57%) 1469 1293 -176 (-11.98%)
bpf_host.o tail_nodeport_nat_ingress_ipv4 5526 3534 -1992 (-36.05%) 366 243 -123 (-33.61%)
bpf_host.o tail_nodeport_nat_ingress_ipv6 5132 4256 -876 (-17.07%) 241 219 -22 (-9.13%)
bpf_host.o tail_nodeport_nat_ipv6_egress 3702 3542 -160 (-4.32%) 215 205 -10 (-4.65%)
bpf_lxc.o tail_handle_nat_fwd_ipv4 21022 10479 -10543 (-50.15%) 1289 670 -619 (-48.02%)
bpf_lxc.o tail_handle_nat_fwd_ipv6 15433 11375 -4058 (-26.29%) 905 643 -262 (-28.95%)
bpf_lxc.o tail_ipv4_ct_egress 5073 3374 -1699 (-33.49%) 262 172 -90 (-34.35%)
bpf_lxc.o tail_ipv4_ct_ingress 5093 3385 -1708 (-33.54%) 262 172 -90 (-34.35%)
bpf_lxc.o tail_ipv4_ct_ingress_policy_only 5093 3385 -1708 (-33.54%) 262 172 -90 (-34.35%)
bpf_lxc.o tail_ipv6_ct_egress 4593 3878 -715 (-15.57%) 194 151 -43 (-22.16%)
bpf_lxc.o tail_ipv6_ct_ingress 4606 3891 -715 (-15.52%) 194 151 -43 (-22.16%)
bpf_lxc.o tail_ipv6_ct_ingress_policy_only 4606 3891 -715 (-15.52%) 194 151 -43 (-22.16%)
bpf_lxc.o tail_nodeport_nat_ingress_ipv4 5526 3534 -1992 (-36.05%) 366 243 -123 (-33.61%)
bpf_lxc.o tail_nodeport_nat_ingress_ipv6 5132 4256 -876 (-17.07%) 241 219 -22 (-9.13%)
bpf_overlay.o tail_handle_nat_fwd_ipv4 20524 10114 -10410 (-50.72%) 1271 638 -633 (-49.80%)
bpf_overlay.o tail_nodeport_nat_egress_ipv4 22718 19490 -3228 (-14.21%) 1475 1275 -200 (-13.56%)
bpf_overlay.o tail_nodeport_nat_ingress_ipv4 5526 3534 -1992 (-36.05%) 366 243 -123 (-33.61%)
bpf_overlay.o tail_nodeport_nat_ingress_ipv6 5132 4256 -876 (-17.07%) 241 219 -22 (-9.13%)
bpf_overlay.o tail_nodeport_nat_ipv6_egress 3638 3548 -90 (-2.47%) 209 203 -6 (-2.87%)
bpf_overlay.o tail_rev_nodeport_lb4 4368 3820 -548 (-12.55%) 248 215 -33 (-13.31%)
bpf_overlay.o tail_rev_nodeport_lb6 2867 2428 -439 (-15.31%) 167 140 -27 (-16.17%)
bpf_sock.o cil_sock6_connect 1718 1703 -15 (-0.87%) 100 99 -1 (-1.00%)
bpf_xdp.o tail_handle_nat_fwd_ipv4 12917 12443 -474 (-3.67%) 875 849 -26 (-2.97%)
bpf_xdp.o tail_handle_nat_fwd_ipv6 13515 13264 -251 (-1.86%) 715 702 -13 (-1.82%)
bpf_xdp.o tail_lb_ipv4 39492 36367 -3125 (-7.91%) 2430 2251 -179 (-7.37%)
bpf_xdp.o tail_lb_ipv6 80441 78058 -2383 (-2.96%) 3647 3523 -124 (-3.40%)
bpf_xdp.o tail_nodeport_ipv6_dsr 1038 901 -137 (-13.20%) 61 55 -6 (-9.84%)
bpf_xdp.o tail_nodeport_nat_egress_ipv4 13027 12096 -931 (-7.15%) 868 809 -59 (-6.80%)
bpf_xdp.o tail_nodeport_nat_ingress_ipv4 7617 5900 -1717 (-22.54%) 522 413 -109 (-20.88%)
bpf_xdp.o tail_nodeport_nat_ingress_ipv6 7575 7395 -180 (-2.38%) 383 374 -9 (-2.35%)
bpf_xdp.o tail_rev_nodeport_lb4 6808 6739 -69 (-1.01%) 403 396 -7 (-1.74%)
bpf_xdp.o tail_rev_nodeport_lb6 16173 15847 -326 (-2.02%) 1010 990 -20 (-1.98%)
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231205184248.1502704-9-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
e322f0bcb8 |
bpf: preserve constant zero when doing partial register restore
Similar to special handling of STACK_ZERO, when reading 1/2/4 bytes from stack from slot that has register spilled into it and that register has a constant value zero, preserve that zero and mark spilled register as precise for that. This makes spilled const zero register and STACK_ZERO cases equivalent in their behavior. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231205184248.1502704-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
eaf18febd6 |
bpf: preserve STACK_ZERO slots on partial reg spills
Instead of always forcing STACK_ZERO slots to STACK_MISC, preserve it in situations where this is possible. E.g., when spilling register as 1/2/4-byte subslots on the stack, all the remaining bytes in the stack slot do not automatically become unknown. If we knew they contained zeroes, we can preserve those STACK_ZERO markers. Add a helper mark_stack_slot_misc(), similar to scrub_spilled_slot(), but that doesn't overwrite either STACK_INVALID nor STACK_ZERO. Note that we need to take into account possibility of being in unprivileged mode, in which case STACK_INVALID is forced to STACK_MISC for correctness, as treating STACK_INVALID as equivalent STACK_MISC is only enabled in privileged mode. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231205184248.1502704-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
ab125ed3ec |
bpf: fix check for attempt to corrupt spilled pointer
When register is spilled onto a stack as a 1/2/4-byte register, we set
slot_type[BPF_REG_SIZE - 1] (plus potentially few more below it,
depending on actual spill size). So to check if some stack slot has
spilled register we need to consult slot_type[7], not slot_type[0].
To avoid the need to remember and double-check this in the future, just
use is_spilled_reg() helper.
Fixes:
|
|
|
Andrii Nakryiko
|
41f6f64e69 |
bpf: support non-r10 register spill/fill to/from stack in precision tracking
Use instruction (jump) history to record instructions that performed register spill/fill to/from stack, regardless if this was done through read-only r10 register, or any other register after copying r10 into it *and* potentially adjusting offset. To make this work reliably, we push extra per-instruction flags into instruction history, encoding stack slot index (spi) and stack frame number in extra 10 bit flags we take away from prev_idx in instruction history. We don't touch idx field for maximum performance, as it's checked most frequently during backtracking. This change removes basically the last remaining practical limitation of precision backtracking logic in BPF verifier. It fixes known deficiencies, but also opens up new opportunities to reduce number of verified states, explored in the subsequent patches. There are only three differences in selftests' BPF object files according to veristat, all in the positive direction (less states). File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) -------------------------------------- ------------- --------- --------- ------------- ---------- ---------- ------------- test_cls_redirect_dynptr.bpf.linked3.o cls_redirect 2987 2864 -123 (-4.12%) 240 231 -9 (-3.75%) xdp_synproxy_kern.bpf.linked3.o syncookie_tc 82848 82661 -187 (-0.23%) 5107 5073 -34 (-0.67%) xdp_synproxy_kern.bpf.linked3.o syncookie_xdp 85116 84964 -152 (-0.18%) 5162 5130 -32 (-0.62%) Note, I avoided renaming jmp_history to more generic insn_hist to minimize number of lines changed and potential merge conflicts between bpf and bpf-next trees. Notice also cur_hist_entry pointer reset to NULL at the beginning of instruction verification loop. This pointer avoids the problem of relying on last jump history entry's insn_idx to determine whether we already have entry for current instruction or not. It can happen that we added jump history entry because current instruction is_jmp_point(), but also we need to add instruction flags for stack access. In this case, we don't want to entries, so we need to reuse last added entry, if it is present. Relying on insn_idx comparison has the same ambiguity problem as the one that was fixed recently in [0], so we avoid that. [0] https://patchwork.kernel.org/project/netdevbpf/patch/20231110002638.4168352-3-andrii@kernel.org/ Acked-by: Eduard Zingerman <eddyz87@gmail.com> Reported-by: Tao Lyu <tao.lyu@epfl.ch> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231205184248.1502704-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Hou Tao
|
af66bfd3c8 |
bpf: Optimize the free of inner map
When removing the inner map from the outer map, the inner map will be freed after one RCU grace period and one RCU tasks trace grace period, so it is certain that the bpf program, which may access the inner map, has exited before the inner map is freed. However there is no need to wait for one RCU tasks trace grace period if the outer map is only accessed by non-sleepable program. So adding sleepable_refcnt in bpf_map and increasing sleepable_refcnt when adding the outer map into env->used_maps for sleepable program. Although the max number of bpf program is INT_MAX - 1, the number of bpf programs which are being loaded may be greater than INT_MAX, so using atomic64_t instead of atomic_t for sleepable_refcnt. When removing the inner map from the outer map, using sleepable_refcnt to decide whether or not a RCU tasks trace grace period is needed before freeing the inner map. Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231204140425.1480317-6-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Hou Tao
|
8766733641 |
bpf: Defer the free of inner map when necessary
When updating or deleting an inner map in map array or map htab, the map may still be accessed by non-sleepable program or sleepable program. However bpf_map_fd_put_ptr() decreases the ref-counter of the inner map directly through bpf_map_put(), if the ref-counter is the last one (which is true for most cases), the inner map will be freed by ops->map_free() in a kworker. But for now, most .map_free() callbacks don't use synchronize_rcu() or its variants to wait for the elapse of a RCU grace period, so after the invocation of ops->map_free completes, the bpf program which is accessing the inner map may incur use-after-free problem. Fix the free of inner map by invoking bpf_map_free_deferred() after both one RCU grace period and one tasks trace RCU grace period if the inner map has been removed from the outer map before. The deferment is accomplished by using call_rcu() or call_rcu_tasks_trace() when releasing the last ref-counter of bpf map. The newly-added rcu_head field in bpf_map shares the same storage space with work field to reduce the size of bpf_map. Fixes: |
|
|
Hou Tao
|
79d93b3c6f |
bpf: Set need_defer as false when clearing fd array during map free
Both map deletion operation, map release and map free operation use fd_array_map_delete_elem() to remove the element from fd array and need_defer is always true in fd_array_map_delete_elem(). For the map deletion operation and map release operation, need_defer=true is necessary, because the bpf program, which accesses the element in fd array, may still alive. However for map free operation, it is certain that the bpf program which owns the fd array has already been exited, so setting need_defer as false is appropriate for map free operation. So fix it by adding need_defer parameter to bpf_fd_array_map_clear() and adding a new helper __fd_array_map_delete_elem() to handle the map deletion, map release and map free operations correspondingly. Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231204140425.1480317-4-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Hou Tao
|
20c20bd11a |
bpf: Add map and need_defer parameters to .map_fd_put_ptr()
map is the pointer of outer map, and need_defer needs some explanation. need_defer tells the implementation to defer the reference release of the passed element and ensure that the element is still alive before the bpf program, which may manipulate it, exits. The following three cases will invoke map_fd_put_ptr() and different need_defer values will be passed to these callers: 1) release the reference of the old element in the map during map update or map deletion. The release must be deferred, otherwise the bpf program may incur use-after-free problem, so need_defer needs to be true. 2) release the reference of the to-be-added element in the error path of map update. The to-be-added element is not visible to any bpf program, so it is OK to pass false for need_defer parameter. 3) release the references of all elements in the map during map release. Any bpf program which has access to the map must have been exited and released, so need_defer=false will be OK. These two parameters will be used by the following patches to fix the potential use-after-free problem for map-in-map. Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231204140425.1480317-3-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Hou Tao
|
169410eba2 |
bpf: Check rcu_read_lock_trace_held() before calling bpf map helpers
These three bpf_map_{lookup,update,delete}_elem() helpers are also
available for sleepable bpf program, so add the corresponding lock
assertion for sleepable bpf program, otherwise the following warning
will be reported when a sleepable bpf program manipulates bpf map under
interpreter mode (aka bpf_jit_enable=0):
WARNING: CPU: 3 PID: 4985 at kernel/bpf/helpers.c:40 ......
CPU: 3 PID: 4985 Comm: test_progs Not tainted 6.6.0+ #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ......
RIP: 0010:bpf_map_lookup_elem+0x54/0x60
......
Call Trace:
<TASK>
? __warn+0xa5/0x240
? bpf_map_lookup_elem+0x54/0x60
? report_bug+0x1ba/0x1f0
? handle_bug+0x40/0x80
? exc_invalid_op+0x18/0x50
? asm_exc_invalid_op+0x1b/0x20
? __pfx_bpf_map_lookup_elem+0x10/0x10
? rcu_lockdep_current_cpu_online+0x65/0xb0
? rcu_is_watching+0x23/0x50
? bpf_map_lookup_elem+0x54/0x60
? __pfx_bpf_map_lookup_elem+0x10/0x10
___bpf_prog_run+0x513/0x3b70
__bpf_prog_run32+0x9d/0xd0
? __bpf_prog_enter_sleepable_recur+0xad/0x120
? __bpf_prog_enter_sleepable_recur+0x3e/0x120
bpf_trampoline_6442580665+0x4d/0x1000
__x64_sys_getpgid+0x5/0x30
? do_syscall_64+0x36/0xb0
entry_SYSCALL_64_after_hwframe+0x6e/0x76
</TASK>
Signed-off-by: Hou Tao <houtao1@huawei.com>
Link: https://lore.kernel.org/r/20231204140425.1480317-2-houtao@huaweicloud.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrei Matei
|
5bd90cdc65 |
bpf: Minor logging improvement
One place where we were logging a register was only logging the variable part, not also the fixed part. Signed-off-by: Andrei Matei <andreimatei1@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20231204011248.2040084-1-andreimatei1@gmail.com |
|
|
Andrii Nakryiko
|
81eff2e364 |
bpf: simplify tnum output if a fully known constant
Emit tnum representation as just a constant if all bits are known. Use decimal-vs-hex logic to determine exact format of emitted constant value, just like it's done for register range values. For that move tnum_strn() to kernel/bpf/log.c to reuse decimal-vs-hex determination logic and constants. Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231202175705.885270-12-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
eabe518de5 |
bpf: enforce precision of R0 on program/async callback return
Given we enforce a valid range for program and async callback return
value, we must mark R0 as precise to avoid incorrect state pruning.
Fixes:
|
|
|
Andrii Nakryiko
|
0ef24c8dfa |
bpf: unify async callback and program retval checks
Use common logic to verify program return values and async callback return values. This allows to avoid duplication of any extra steps necessary, like precision marking, which will be added in the next patch. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231202175705.885270-8-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
c871d0e00f |
bpf: enforce precise retval range on program exit
Similarly to subprog/callback logic, enforce return value of BPF program using more precise smin/smax range. We need to adjust a bunch of tests due to a changed format of an error message. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231202175705.885270-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
8fa4ecd49b |
bpf: enforce exact retval range on subprog/callback exit
Instead of relying on potentially imprecise tnum representation of expected return value range for callbacks and subprogs, validate that smin/smax range satisfy exact expected range of return values. E.g., if callback would need to return [0, 2] range, tnum can't represent this precisely and instead will allow [0, 3] range. By checking smin/smax range, we can make sure that subprog/callback indeed returns only valid [0, 2] range. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231202175705.885270-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
0acd03a5bd |
bpf: enforce precision of R0 on callback return
Given verifier checks actual value, r0 has to be precise, so we need to
propagate precision properly. r0 also has to be marked as read,
otherwise subsequent state comparisons will ignore such register as
unimportant and precision won't really help here.
Fixes:
|
|
|
Andrii Nakryiko
|
5fad52bee3 |
bpf: provide correct register name for exception callback retval check
bpf_throw() is checking R1, so let's report R1 in the log. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231202175705.885270-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Yonghong Song
|
dfce9cb314 |
bpf: Fix a verifier bug due to incorrect branch offset comparison with cpu=v4
Bpf cpu=v4 support is introduced in [1] and Commit |
|
|
Jakub Kicinski
|
753c8608f3 |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZWiCPAAKCRDbK58LschI g4djAQC1FdqCRIFkhbiIRNHTgHjnfQShELQbd9ofJqzylLqmmgD+JI1E7D9SXagm pIXQ26EGmq8/VcCT3VLncA8EsC76Gg4= =Xowm -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2023-11-30 We've added 30 non-merge commits during the last 7 day(s) which contain a total of 58 files changed, 1598 insertions(+), 154 deletions(-). The main changes are: 1) Add initial TX metadata implementation for AF_XDP with support in mlx5 and stmmac drivers. Two types of offloads are supported right now, that is, TX timestamp and TX checksum offload, from Stanislav Fomichev with stmmac implementation from Song Yoong Siang. 2) Change BPF verifier logic to validate global subprograms lazily instead of unconditionally before the main program, so they can be guarded using BPF CO-RE techniques, from Andrii Nakryiko. 3) Add BPF link_info support for uprobe multi link along with bpftool integration for the latter, from Jiri Olsa. 4) Use pkg-config in BPF selftests to determine ld flags which is in particular needed for linking statically, from Akihiko Odaki. 5) Fix a few BPF selftest failures to adapt to the upcoming LLVM18, from Yonghong Song. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (30 commits) bpf/tests: Remove duplicate JSGT tests selftests/bpf: Add TX side to xdp_hw_metadata selftests/bpf: Convert xdp_hw_metadata to XDP_USE_NEED_WAKEUP selftests/bpf: Add TX side to xdp_metadata selftests/bpf: Add csum helpers selftests/xsk: Support tx_metadata_len xsk: Add option to calculate TX checksum in SW xsk: Validate xsk_tx_metadata flags xsk: Document tx_metadata_len layout net: stmmac: Add Tx HWTS support to XDP ZC net/mlx5e: Implement AF_XDP TX timestamp and checksum offload tools: ynl: Print xsk-features from the sample xsk: Add TX timestamp and TX checksum offload support xsk: Support tx_metadata_len selftests/bpf: Use pkg-config for libelf selftests/bpf: Override PKG_CONFIG for static builds selftests/bpf: Choose pkg-config for the target bpftool: Add support to display uprobe_multi links selftests/bpf: Add link_info test for uprobe_multi link selftests/bpf: Use bpf_link__destroy in fill_link_info tests ... ==================== Conflicts: Documentation/netlink/specs/netdev.yaml: |
|
|
Jakub Kicinski
|
975f2d73a9 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Hou Tao
|
75a442581d |
bpf: Add missed allocation hint for bpf_mem_cache_alloc_flags()
bpf_mem_cache_alloc_flags() may call __alloc() directly when there is no
free object in free list, but it doesn't initialize the allocation hint
for the returned pointer. It may lead to bad memory dereference when
freeing the pointer, so fix it by initializing the allocation hint.
Fixes:
|
|
|
Andrii Nakryiko
|
2afae08c9d |
bpf: Validate global subprogs lazily
Slightly change BPF verifier logic around eagerness and order of global subprog validation. Instead of going over every global subprog eagerly and validating it before main (entry) BPF program is verified, turn it around. Validate main program first, mark subprogs that were called from main program for later verification, but otherwise assume it is valid. Afterwards, go over marked global subprogs and validate those, potentially marking some more global functions as being called. Continue this process until all (transitively) callable global subprogs are validated. It's a BFS traversal at its heart and will always converge. This is an important change because it allows to feature-gate some subprograms that might not be verifiable on some older kernel, depending on supported set of features. E.g., at some point, global functions were allowed to accept a pointer to memory, which size is identified by user-provided type. Unfortunately, older kernels don't support this feature. With BPF CO-RE approach, the natural way would be to still compile BPF object file once and guard calls to this global subprog with some CO-RE check or using .rodata variables. That's what people do to guard usage of new helpers or kfuncs, and any other new BPF-side feature that might be missing on old kernels. That's currently impossible to do with global subprogs, unfortunately, because they are eagerly and unconditionally validated. This patch set aims to change this, so that in the future when global funcs gain new features, those can be guarded using BPF CO-RE techniques in the same fashion as any other new kernel feature. Two selftests had to be adjusted in sync with these changes. test_global_func12 relied on eager global subprog validation failing before main program failure is detected (unknown return value). Fix by making sure that main program is always valid. verifier_subprog_precision's parent_stack_slot_precise subtest relied on verifier checkpointing heuristic to do a checkpoint at instruction #5, but that's no longer true because we don't have enough jumps validated before reaching insn #5 due to global subprogs being validated later. Other than that, no changes, as one would expect. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20231124035937.403208-3-andrii@kernel.org |
|
|
Andrii Nakryiko
|
491dd8edec |
bpf: Emit global subprog name in verifier logs
We have the name, instead of emitting just func#N to identify global subprog, augment verifier log messages with actual function name to make it more user-friendly. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20231124035937.403208-2-andrii@kernel.org |
|
|
Jakub Kicinski
|
45c226dde7 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR. Conflicts: drivers/net/ethernet/intel/ice/ice_main.c |
|
|
Jakub Kicinski
|
53475287da |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCZV0kjgAKCRDbK58LschI gy0EAP9XwncW2OhO72DpITluFzvWPgB0N97OANKBXjzKJrRAlQD/aUe9nlvBQuad WsbMKLeC4wvI2X/4PEIR4ukbuZ3ypAA= =LMVg -----END PGP SIGNATURE----- Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2023-11-21 We've added 85 non-merge commits during the last 12 day(s) which contain a total of 63 files changed, 4464 insertions(+), 1484 deletions(-). The main changes are: 1) Huge batch of verifier changes to improve BPF register bounds logic and range support along with a large test suite, and verifier log improvements, all from Andrii Nakryiko. 2) Add a new kfunc which acquires the associated cgroup of a task within a specific cgroup v1 hierarchy where the latter is identified by its id, from Yafang Shao. 3) Extend verifier to allow bpf_refcount_acquire() of a map value field obtained via direct load which is a use-case needed in sched_ext, from Dave Marchevsky. 4) Fix bpf_get_task_stack() helper to add the correct crosstask check for the get_perf_callchain(), from Jordan Rome. 5) Fix BPF task_iter internals where lockless usage of next_thread() was wrong. The rework also simplifies the code, from Oleg Nesterov. 6) Fix uninitialized tail padding via LIBBPF_OPTS_RESET, and another fix for certain BPF UAPI structs to fix verifier failures seen in bpf_dynptr usage, from Yonghong Song. 7) Add BPF selftest fixes for map_percpu_stats flakes due to per-CPU BPF memory allocator not being able to allocate per-CPU pointer successfully, from Hou Tao. 8) Add prep work around dynptr and string handling for kfuncs which is later going to be used by file verification via BPF LSM and fsverity, from Song Liu. 9) Improve BPF selftests to update multiple prog_tests to use ASSERT_* macros, from Yuran Pereira. 10) Optimize LPM trie lookup to check prefixlen before walking the trie, from Florian Lehner. 11) Consolidate virtio/9p configs from BPF selftests in config.vm file given they are needed consistently across archs, from Manu Bretelle. 12) Small BPF verifier refactor to remove register_is_const(), from Shung-Hsi Yu. * tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (85 commits) selftests/bpf: Replaces the usage of CHECK calls for ASSERTs in vmlinux selftests/bpf: Replaces the usage of CHECK calls for ASSERTs in bpf_obj_id selftests/bpf: Replaces the usage of CHECK calls for ASSERTs in bind_perm selftests/bpf: Replaces the usage of CHECK calls for ASSERTs in bpf_tcp_ca selftests/bpf: reduce verboseness of reg_bounds selftest logs bpf: bpf_iter_task_next: use next_task(kit->task) rather than next_task(kit->pos) bpf: bpf_iter_task_next: use __next_thread() rather than next_thread() bpf: task_group_seq_get_next: use __next_thread() rather than next_thread() bpf: emit frameno for PTR_TO_STACK regs if it differs from current one bpf: smarter verifier log number printing logic bpf: omit default off=0 and imm=0 in register state log bpf: emit map name in register state if applicable and available bpf: print spilled register state in stack slot bpf: extract register state printing bpf: move verifier state printing code to kernel/bpf/log.c bpf: move verbose_linfo() into kernel/bpf/log.c bpf: rename BPF_F_TEST_SANITY_STRICT to BPF_F_TEST_REG_INVARIANTS bpf: Remove test for MOVSX32 with offset=32 selftests/bpf: add iter test requiring range x range logic veristat: add ability to set BPF_F_TEST_SANITY_STRICT flag with -r flag ... ==================== Link: https://lore.kernel.org/r/20231122000500.28126-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Eduard Zingerman
|
bb124da69c |
bpf: keep track of max number of bpf_loop callback iterations
In some cases verifier can't infer convergence of the bpf_loop()
iteration. E.g. for the following program:
static int cb(__u32 idx, struct num_context* ctx)
{
ctx->i++;
return 0;
}
SEC("?raw_tp")
int prog(void *_)
{
struct num_context ctx = { .i = 0 };
__u8 choice_arr[2] = { 0, 1 };
bpf_loop(2, cb, &ctx, 0);
return choice_arr[ctx.i];
}
Each 'cb' simulation would eventually return to 'prog' and reach
'return choice_arr[ctx.i]' statement. At which point ctx.i would be
marked precise, thus forcing verifier to track multitude of separate
states with {.i=0}, {.i=1}, ... at bpf_loop() callback entry.
This commit allows "brute force" handling for such cases by limiting
number of callback body simulations using 'umax' value of the first
bpf_loop() parameter.
For this, extend bpf_func_state with 'callback_depth' field.
Increment this field when callback visiting state is pushed to states
traversal stack. For frame #N it's 'callback_depth' field counts how
many times callback with frame depth N+1 had been executed.
Use bpf_func_state specifically to allow independent tracking of
callback depths when multiple nested bpf_loop() calls are present.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20231121020701.26440-11-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Eduard Zingerman
|
cafe2c2150 |
bpf: widening for callback iterators
Callbacks are similar to open coded iterators, so add imprecise
widening logic for callback body processing. This makes callback based
loops behave identically to open coded iterators, e.g. allowing to
verify programs like below:
struct ctx { u32 i; };
int cb(u32 idx, struct ctx* ctx)
{
++ctx->i;
return 0;
}
...
struct ctx ctx = { .i = 0 };
bpf_loop(100, cb, &ctx, 0);
...
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20231121020701.26440-9-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Eduard Zingerman
|
ab5cfac139 |
bpf: verify callbacks as if they are called unknown number of times
Prior to this patch callbacks were handled as regular function calls,
execution of callback body was modeled exactly once.
This patch updates callbacks handling logic as follows:
- introduces a function push_callback_call() that schedules callback
body verification in env->head stack;
- updates prepare_func_exit() to reschedule callback body verification
upon BPF_EXIT;
- as calls to bpf_*_iter_next(), calls to callback invoking functions
are marked as checkpoints;
- is_state_visited() is updated to stop callback based iteration when
some identical parent state is found.
Paths with callback function invoked zero times are now verified first,
which leads to necessity to modify some selftests:
- the following negative tests required adding release/unlock/drop
calls to avoid previously masked unrelated error reports:
- cb_refs.c:underflow_prog
- exceptions_fail.c:reject_rbtree_add_throw
- exceptions_fail.c:reject_with_cp_reference
- the following precision tracking selftests needed change in expected
log trace:
- verifier_subprog_precision.c:callback_result_precise
(note: r0 precision is no longer propagated inside callback and
I think this is a correct behavior)
- verifier_subprog_precision.c:parent_callee_saved_reg_precise_with_callback
- verifier_subprog_precision.c:parent_stack_slot_precise_with_callback
Reported-by: Andrew Werner <awerner32@gmail.com>
Closes: https://lore.kernel.org/bpf/CA+vRuzPChFNXmouzGG+wsy=6eMcfr1mFG0F3g7rbg-sedGKW3w@mail.gmail.com/
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20231121020701.26440-7-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Eduard Zingerman
|
58124a98cb |
bpf: extract setup_func_entry() utility function
Move code for simulated stack frame creation to a separate utility function. This function would be used in the follow-up change for callbacks handling. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20231121020701.26440-6-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Eduard Zingerman
|
683b96f960 |
bpf: extract __check_reg_arg() utility function
Split check_reg_arg() into two utility functions: - check_reg_arg() operating on registers from current verifier state; - __check_reg_arg() operating on a specific set of registers passed as a parameter; The __check_reg_arg() function would be used by a follow-up change for callbacks handling. Acked-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Eduard Zingerman <eddyz87@gmail.com> Link: https://lore.kernel.org/r/20231121020701.26440-5-eddyz87@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Oleg Nesterov
|
ac8148d957 |
bpf: bpf_iter_task_next: use next_task(kit->task) rather than next_task(kit->pos)
This looks more clear and simplifies the code. While at it, remove the unnecessary initialization of pos/task at the start of bpf_iter_task_new(). Note that we can even kill kit->task, we can just use pos->group_leader, but I don't understand the BUILD_BUG_ON() checks in bpf_iter_task_new(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20231114163239.GA903@redhat.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Oleg Nesterov
|
5a34f9dabd |
bpf: bpf_iter_task_next: use __next_thread() rather than next_thread()
Lockless use of next_thread() should be avoided, kernel/bpf/task_iter.c is the last user and the usage is wrong. bpf_iter_task_next() can loop forever, "kit->pos == kit->task" can never happen if kit->pos execs. Change this code to use __next_thread(). With or without this change the usage of kit->pos/task and next_task() doesn't look nice, see the next patch. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20231114163237.GA897@redhat.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Oleg Nesterov
|
2d1618054f |
bpf: task_group_seq_get_next: use __next_thread() rather than next_thread()
Lockless use of next_thread() should be avoided, kernel/bpf/task_iter.c is the last user and the usage is wrong. task_group_seq_get_next() can return the group leader twice if it races with mt-thread exec which changes the group->leader's pid. Change the main loop to use __next_thread(), kill "next_tid == common->pid" check. __next_thread() can't loop forever, we can also change this code to retry if next_tid == 0. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Yonghong Song <yonghong.song@linux.dev> Link: https://lore.kernel.org/r/20231114163234.GA890@redhat.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
46862ee854 |
bpf: emit frameno for PTR_TO_STACK regs if it differs from current one
It's possible to pass a pointer to parent's stack to child subprogs. In such case verifier state output is ambiguous not showing whether register container a pointer to "current" stack, belonging to current subprog (frame), or it's actually a pointer to one of parent frames. So emit this information if frame number differs between the state which register is part of. E.g., if current state is in frame 2 and it has a register pointing to stack in grand parent state (frame #0), we'll see something like 'R1=fp[0]-16', while "local stack pointer" will be just 'R2=fp-16'. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231118034623.3320920-9-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
0f8dbdbc64 |
bpf: smarter verifier log number printing logic
Instead of always printing numbers as either decimals (and in some cases, like for "imm=%llx", in hexadecimals), decide the form based on actual values. For numbers in a reasonably small range (currently, [0, U16_MAX] for unsigned values, and [S16_MIN, S16_MAX] for signed ones), emit them as decimals. In all other cases, even for signed values, emit them in hexadecimals. For large values hex form is often times way more useful: it's easier to see an exact difference between 0xffffffff80000000 and 0xffffffff7fffffff, than between 18446744071562067966 and 18446744071562067967, as one particular example. Small values representing small pointer offsets or application constants, on the other hand, are way more useful to be represented in decimal notation. Adjust reg_bounds register state parsing logic to take into account this change. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231118034623.3320920-8-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
1db747d75b |
bpf: omit default off=0 and imm=0 in register state log
Simplify BPF verifier log further by omitting default (and frequently irrelevant) off=0 and imm=0 parts for non-SCALAR_VALUE registers. As can be seen from fixed tests, this is often a visual noise for PTR_TO_CTX register and even for PTR_TO_PACKET registers. Omitting default values follows the rest of register state logic: we omit default values to keep verifier log succinct and to highlight interesting state that deviates from default one. E.g., we do the same for var_off, when it's unknown, which gives no additional information. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231118034623.3320920-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
0c95c9fdb6 |
bpf: emit map name in register state if applicable and available
In complicated real-world applications, whenever debugging some verification error through verifier log, it often would be very useful to see map name for PTR_TO_MAP_VALUE register. Usually this needs to be inferred from key/value sizes and maybe trying to guess C code location, but it's not always clear. Given verifier has the name, and it's never too long, let's just emit it for ptr_to_map_key, ptr_to_map_value, and const_ptr_to_map registers. We reshuffle the order a bit, so that map name, key size, and value size appear before offset and immediate values, which seems like a more logical order. Current output: R1_w=map_ptr(map=array_map,ks=4,vs=8,off=0,imm=0) But we'll get rid of useless off=0 and imm=0 parts in the next patch. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231118034623.3320920-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
67d43dfbb4 |
bpf: print spilled register state in stack slot
Print the same register state representation when printing stack state,
as we do for normal registers. Note that if stack slot contains
subregister spill (1, 2, or 4 byte long), we'll still emit "m0?" mask
for those bytes that are not part of spilled register.
While means we can get something like fp-8=0000scalar() for a 4-byte
spill with other 4 bytes still being STACK_ZERO.
Some example before and after, taken from the log of
pyperf_subprogs.bpf.o:
49: (7b) *(u64 *)(r10 -256) = r1 ; frame1: R1_w=ctx(off=0,imm=0) R10=fp0 fp-256_w=ctx
49: (7b) *(u64 *)(r10 -256) = r1 ; frame1: R1_w=ctx(off=0,imm=0) R10=fp0 fp-256_w=ctx(off=0,imm=0)
150: (7b) *(u64 *)(r10 -264) = r0 ; frame1: R0_w=map_value_or_null(id=6,off=0,ks=192,vs=4,imm=0) R10=fp0 fp-264_w=map_value_or_null
150: (7b) *(u64 *)(r10 -264) = r0 ; frame1: R0_w=map_value_or_null(id=6,off=0,ks=192,vs=4,imm=0) R10=fp0 fp-264_w=map_value_or_null(id=6,off=0,ks=192,vs=4,imm=0)
5192: (61) r1 = *(u32 *)(r10 -272) ; frame1: R1_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=15,var_off=(0x0; 0xf)) R10=fp0 fp-272=
5192: (61) r1 = *(u32 *)(r10 -272) ; frame1: R1_w=scalar(smin=smin32=0,smax=umax=smax32=umax32=15,var_off=(0x0; 0xf)) R10=fp0 fp-272=????scalar(smin=smin32=0,smax=umax=smax32=umax32=15,var_off=(0x0; 0xf))
While at it, do a few other simple clean ups:
- skip slot if it's not scratched before detecting whether it's valid;
- move taking spilled_reg pointer outside of switch (only DYNPTR has
to adjust that to get to the "main" slot);
- don't recalculate types_buf second time for MISC/ZERO/default case.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231118034623.3320920-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
009f5465be |
bpf: extract register state printing
Extract printing register state representation logic into a separate helper, as we are going to reuse it for spilled register state printing in the next patch. This also nicely reduces code nestedness. No functional changes. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231118034623.3320920-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
42feb6620a |
bpf: move verifier state printing code to kernel/bpf/log.c
Move a good chunk of code from verifier.c to log.c: verifier state verbose printing logic. This is an important and very much logging/debugging oriented code. It fits the overlall log.c's focus on verifier logging, and moving it allows to keep growing it without unnecessarily adding to verifier.c code that otherwise contains a core verification logic. There are not many shared dependencies between this code and the rest of verifier.c code, except a few single-line helpers for various register type checks and a bit of state "scratching" helpers. We move all such trivial helpers into include/bpf/bpf_verifier.h as static inlines. No functional changes in this patch. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231118034623.3320920-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
db840d389b |
bpf: move verbose_linfo() into kernel/bpf/log.c
verifier.c is huge. Let's try to move out parts that are logging-related into log.c, as we previously did with bpf_log() and other related stuff. This patch moves line info verbose output routines: it's pretty self-contained and isolated code, so there is no problem with this. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231118034623.3320920-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
ff8867af01 |
bpf: rename BPF_F_TEST_SANITY_STRICT to BPF_F_TEST_REG_INVARIANTS
Rename verifier internal flag BPF_F_TEST_SANITY_STRICT to more neutral BPF_F_TEST_REG_INVARIANTS. This is a follow up to [0]. A few selftests and veristat need to be adjusted in the same patch as well. [0] https://patchwork.kernel.org/project/netdevbpf/patch/20231112010609.848406-5-andrii@kernel.org/ Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231117171404.225508-1-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
cf5fe3c71c |
bpf: make __reg{32,64}_deduce_bounds logic more robust
This change doesn't seem to have any effect on selftests and production BPF object files, but we preemptively try to make it more robust. First, "learn sign from signed bounds" comment is misleading, as we are learning not just sign, but also values. Second, we simplify the check for determining whether entire range is positive or negative similarly to other checks added earlier, using appropriate u32/u64 cast and single comparisons. As explain in comments in __reg64_deduce_bounds(), the checks are equivalent. Last but not least, smin/smax and s32_min/s32_max reassignment based on min/max of both umin/umax and smin/smax (and 32-bit equivalents) is hard to explain and justify. We are updating unsigned bounds from signed bounds, why would we update signed bounds at the same time? This might be correct, but it's far from obvious why and the code or comments don't try to justify this. Given we've added a separate deduction of signed bounds from unsigned bounds earlier, this seems at least redundant, if not just wrong. In short, we remove doubtful pieces, and streamline the rest to follow the logic and approach of the rest of reg_bounds_sync() checks. Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231112010609.848406-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
3cf98cf594 |
bpf: remove redundant s{32,64} -> u{32,64} deduction logic
Equivalent checks were recently added in more succinct and, arguably,
safer form in:
- f188765f23a5 ("bpf: derive smin32/smax32 from umin32/umax32 bounds");
- 2e74aef782d3 ("bpf: derive smin/smax from umin/max bounds").
The checks we are removing in this patch set do similar checks to detect
if entire u32/u64 range has signed bit set or not set, but does it with
two separate checks.
Further, we forcefully overwrite either smin or smax (and 32-bit equvalents)
without applying normal min/max intersection logic. It's not clear why
that would be correct in all cases and seems to work by accident. This
logic is also "gated" by previous signed -> unsigned derivation, which
returns early.
All this is quite confusing and seems error-prone, while we already have
at least equivalent checks happening earlier. So remove this duplicate
and error-prone logic to simplify things a bit.
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231112010609.848406-6-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
5f99f312bd |
bpf: add register bounds sanity checks and sanitization
Add simple sanity checks that validate well-formed ranges (min <= max) across u64, s64, u32, and s32 ranges. Also for cases when the value is constant (either 64-bit or 32-bit), we validate that ranges and tnums are in agreement. These bounds checks are performed at the end of BPF_ALU/BPF_ALU64 operations, on conditional jumps, and for LDX instructions (where subreg zero/sign extension is probably the most important to check). This covers most of the interesting cases. Also, we validate the sanity of the return register when manually adjusting it for some special helpers. By default, sanity violation will trigger a warning in verifier log and resetting register bounds to "unbounded" ones. But to aid development and debugging, BPF_F_TEST_SANITY_STRICT flag is added, which will trigger hard failure of verification with -EFAULT on register bounds violations. This allows selftests to catch such issues. veristat will also gain a CLI option to enable this behavior. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://lore.kernel.org/r/20231112010609.848406-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
be41a203bb |
bpf: enhance BPF_JEQ/BPF_JNE is_branch_taken logic
Use 32-bit subranges to prune some 64-bit BPF_JEQ/BPF_JNE conditions that otherwise would be "inconclusive" (i.e., is_branch_taken() would return -1). This can happen, for example, when registers are initialized as 64-bit u64/s64, then compared for inequality as 32-bit subregisters, and then followed by 64-bit equality/inequality check. That 32-bit inequality can establish some pattern for lower 32 bits of a register (e.g., s< 0 condition determines whether the bit #31 is zero or not), while overall 64-bit value could be anything (according to a value range representation). This is not a fancy quirky special case, but actually a handling that's necessary to prevent correctness issue with BPF verifier's range tracking: set_range_min_max() assumes that register ranges are non-overlapping, and if that condition is not guaranteed by is_branch_taken() we can end up with invalid ranges, where min > max. [0] https://lore.kernel.org/bpf/CACkBjsY2q1_fUohD7hRmKGqv1MV=eP2f6XK8kjkYNw7BaiF8iQ@mail.gmail.com/ Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231112010609.848406-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
96381879a3 |
bpf: generalize is_scalar_branch_taken() logic
Generalize is_branch_taken logic for SCALAR_VALUE register to handle cases when both registers are not constants. Previously supported <range> vs <scalar> cases are a natural subset of more generic <range> vs <range> set of cases. Generalized logic relies on straightforward segment intersection checks. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://lore.kernel.org/r/20231112010609.848406-3-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
67420501e8 |
bpf: generalize reg_set_min_max() to handle non-const register comparisons
Generalize bounds adjustment logic of reg_set_min_max() to handle not just register vs constant case, but in general any register vs any register cases. For most of the operations it's trivial extension based on range vs range comparison logic, we just need to properly pick min/max of a range to compare against min/max of the other range. For BPF_JSET we keep the original capabilities, just make sure JSET is integrated in the common framework. This is manifested in the internal-only BPF_JSET + BPF_X "opcode" to allow for simpler and more uniform rev_opcode() handling. See the code for details. This allows to reuse the same code exactly both for TRUE and FALSE branches without explicitly handling both conditions with custom code. Note also that now we don't need a special handling of BPF_JEQ/BPF_JNE case none of the registers are constants. This is now just a normal generic case handled by reg_set_min_max(). To make tnum handling cleaner, tnum_with_subreg() helper is added, as that's a common operator when dealing with 32-bit subregister bounds. This keeps the overall logic much less noisy when it comes to tnums. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://lore.kernel.org/r/20231112010609.848406-2-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Yonghong Song
|
1fda5bb66a |
bpf: Do not allocate percpu memory at init stage
Kirill Shutemov reported significant percpu memory consumption increase after booting in 288-cpu VM ([1]) due to commit |
|
|
Yafang Shao
|
fe977716b4 |
bpf: Add a new kfunc for cgroup1 hierarchy
A new kfunc is added to acquire cgroup1 of a task: - bpf_task_get_cgroup1 Acquires the associated cgroup of a task whithin a specific cgroup1 hierarchy. The cgroup1 hierarchy is identified by its hierarchy ID. This new kfunc enables the tracing of tasks within a designated container or cgroup directory in BPF programs. Suggested-by: Tejun Heo <tj@kernel.org> Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Tejun Heo <tj@kernel.org> Link: https://lore.kernel.org/r/20231111090034.4248-2-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Jordan Rome
|
b8e3a87a62 |
bpf: Add crosstask check to __bpf_get_stack
Currently get_perf_callchain only supports user stack walking for
the current task. Passing the correct *crosstask* param will return
0 frames if the task passed to __bpf_get_stack isn't the current
one instead of a single incorrect frame/address. This change
passes the correct *crosstask* param but also does a preemptive
check in __bpf_get_stack if the task is current and returns
-EOPNOTSUPP if it is not.
This issue was found using bpf_get_task_stack inside a BPF
iterator ("iter/task"), which iterates over all tasks.
bpf_get_task_stack works fine for fetching kernel stacks
but because get_perf_callchain relies on the caller to know
if the requested *task* is the current one (via *crosstask*)
it was failing in a confusing way.
It might be possible to get user stacks for all tasks utilizing
something like access_process_vm but that requires the bpf
program calling bpf_get_task_stack to be sleepable and would
therefore be a breaking change.
Fixes:
|
|
|
Andrii Nakryiko
|
10e14e9652 |
bpf: fix control-flow graph checking in privileged mode
When BPF program is verified in privileged mode, BPF verifier allows
bounded loops. This means that from CFG point of view there are
definitely some back-edges. Original commit adjusted check_cfg() logic
to not detect back-edges in control flow graph if they are resulting
from conditional jumps, which the idea that subsequent full BPF
verification process will determine whether such loops are bounded or
not, and either accept or reject the BPF program. At least that's my
reading of the intent.
Unfortunately, the implementation of this idea doesn't work correctly in
all possible situations. Conditional jump might not result in immediate
back-edge, but just a few unconditional instructions later we can arrive
at back-edge. In such situations check_cfg() would reject BPF program
even in privileged mode, despite it might be bounded loop. Next patch
adds one simple program demonstrating such scenario.
To keep things simple, instead of trying to detect back edges in
privileged mode, just assume every back edge is valid and let subsequent
BPF verification prove or reject bounded loops.
Note a few test changes. For unknown reason, we have a few tests that
are specified to detect a back-edge in a privileged mode, but looking at
their code it seems like the right outcome is passing check_cfg() and
letting subsequent verification to make a decision about bounded or not
bounded looping.
Bounded recursion case is also interesting. The example should pass, as
recursion is limited to just a few levels and so we never reach maximum
number of nested frames and never exhaust maximum stack depth. But the
way that max stack depth logic works today it falsely detects this as
exceeding max nested frame count. This patch series doesn't attempt to
fix this orthogonal problem, so we just adjust expected verifier failure.
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Fixes:
|
|
|
Andrii Nakryiko
|
4bb7ea946a |
bpf: fix precision backtracking instruction iteration
Fix an edge case in __mark_chain_precision() which prematurely stops
backtracking instructions in a state if it happens that state's first
and last instruction indexes are the same. This situations doesn't
necessarily mean that there were no instructions simulated in a state,
but rather that we starting from the instruction, jumped around a bit,
and then ended up at the same instruction before checkpointing or
marking precision.
To distinguish between these two possible situations, we need to consult
jump history. If it's empty or contain a single record "bridging" parent
state and first instruction of processed state, then we indeed
backtracked all instructions in this state. But if history is not empty,
we are definitely not done yet.
Move this logic inside get_prev_insn_idx() to contain it more nicely.
Use -ENOENT return code to denote "we are out of instructions"
situation.
This bug was exposed by verifier_loop1.c's bounded_recursion subtest, once
the next fix in this patch set is applied.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Fixes:
|
|
|
Andrii Nakryiko
|
3feb263bb5 |
bpf: handle ldimm64 properly in check_cfg()
ldimm64 instructions are 16-byte long, and so have to be handled
appropriately in check_cfg(), just like the rest of BPF verifier does.
This has implications in three places:
- when determining next instruction for non-jump instructions;
- when determining next instruction for callback address ldimm64
instructions (in visit_func_call_insn());
- when checking for unreachable instructions, where second half of
ldimm64 is expected to be unreachable;
We take this also as an opportunity to report jump into the middle of
ldimm64. And adjust few test_verifier tests accordingly.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Reported-by: Hao Sun <sunhao.th@gmail.com>
Fixes:
|
|
|
Dave Marchevsky
|
1b12171533 |
bpf: Mark direct ld of stashed bpf_{rb,list}_node as non-owning ref
This patch enables the following pattern:
/* mapval contains a __kptr pointing to refcounted local kptr */
mapval = bpf_map_lookup_elem(&map, &idx);
if (!mapval || !mapval->some_kptr) { /* omitted */ }
p = bpf_refcount_acquire(&mapval->some_kptr);
Currently this doesn't work because bpf_refcount_acquire expects an
owning or non-owning ref. The verifier defines non-owning ref as a type:
PTR_TO_BTF_ID | MEM_ALLOC | NON_OWN_REF
while mapval->some_kptr is PTR_TO_BTF_ID | PTR_UNTRUSTED. It's possible
to do the refcount_acquire by first bpf_kptr_xchg'ing mapval->some_kptr
into a temp kptr, refcount_acquiring that, and xchg'ing back into
mapval, but this is unwieldy and shouldn't be necessary.
This patch modifies btf_ld_kptr_type such that user-allocated types are
marked MEM_ALLOC and if those types have a bpf_{rb,list}_node they're
marked NON_OWN_REF as well. Additionally, due to changes to
bpf_obj_drop_impl earlier in this series, rcu_protected_object now
returns true for all user-allocated types, resulting in
mapval->some_kptr being marked MEM_RCU.
After this patch's changes, mapval->some_kptr is now:
PTR_TO_BTF_ID | MEM_ALLOC | NON_OWN_REF | MEM_RCU
which results in it passing the non-owning ref test, and the motivating
example passing verification.
Future work will likely get rid of special non-owning ref lifetime logic
in the verifier, at which point we'll be able to delete the NON_OWN_REF
flag entirely.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20231107085639.3016113-6-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Dave Marchevsky
|
790ce3cfef |
bpf: Move GRAPH_{ROOT,NODE}_MASK macros into btf_field_type enum
This refactoring patch removes the unused BPF_GRAPH_NODE_OR_ROOT
btf_field_type and moves BPF_GRAPH_{NODE,ROOT} macros into the
btf_field_type enum. Further patches in the series will use
BPF_GRAPH_NODE, so let's move this useful definition out of btf.c.
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20231107085639.3016113-5-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Dave Marchevsky
|
649924b76a |
bpf: Use bpf_mem_free_rcu when bpf_obj_dropping non-refcounted nodes
The use of bpf_mem_free_rcu to free refcounted local kptrs was added
in commit
|
|
|
Dave Marchevsky
|
1500a5d9f4 |
bpf: Add KF_RCU flag to bpf_refcount_acquire_impl
Refcounted local kptrs are kptrs to user-defined types with a bpf_refcount field. Recent commits ([0], [1]) modified the lifetime of refcounted local kptrs such that the underlying memory is not reused until RCU grace period has elapsed. Separately, verification of bpf_refcount_acquire calls currently succeeds for MAYBE_NULL non-owning reference input, which is a problem as bpf_refcount_acquire_impl has no handling for this case. This patch takes advantage of aforementioned lifetime changes to tag bpf_refcount_acquire_impl kfunc KF_RCU, thereby preventing MAYBE_NULL input to the kfunc. The KF_RCU flag applies to all kfunc params; it's fine for it to apply to the void *meta__ign param as that's populated by the verifier and is tagged __ign regardless. [0]: commit |
|
|
Shung-Hsi Yu
|
82ce364c60 |
bpf: replace register_is_const() with is_reg_const()
The addition of is_reg_const() in commit 171de12646d2 ("bpf: generalize
is_branch_taken to handle all conditional jumps in one place") has made the
register_is_const() redundant. Give the former has more feature, plus the
fact the latter is only used in one place, replace register_is_const() with
is_reg_const(), and remove the definition of register_is_const.
This requires moving the definition of is_reg_const() further up. And since
the comment of reg_const_value() reference is_reg_const(), move it up as
well.
Signed-off-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20231108140043.12282-1-shung-hsi.yu@suse.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Song Liu
|
045edee19d |
bpf: Introduce KF_ARG_PTR_TO_CONST_STR
Similar to ARG_PTR_TO_CONST_STR for BPF helpers, KF_ARG_PTR_TO_CONST_STR specifies kfunc args that point to const strings. Annotation "__str" is used to specify kfunc arg of type KF_ARG_PTR_TO_CONST_STR. Also, add documentation for the "__str" annotation. bpf_get_file_xattr() will be the first kfunc that uses this type. Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Link: https://lore.kernel.org/bpf/20231107045725.2278852-4-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Song Liu
|
0b51940729 |
bpf: Factor out helper check_reg_const_str()
ARG_PTR_TO_CONST_STR is used to specify constant string args for BPF helpers. The logic that verifies a reg is ARG_PTR_TO_CONST_STR is implemented in check_func_arg(). As we introduce kfuncs with constant string args, it is necessary to do the same check for kfuncs (in check_kfunc_args). Factor out the logic for ARG_PTR_TO_CONST_STR to a new check_reg_const_str() so that it can be reused. check_func_arg() ensures check_reg_const_str() is only called with reg of type PTR_TO_MAP_VALUE. Add a redundent type check in check_reg_const_str() to avoid misuse in the future. Other than this redundent check, there is no change in behavior. Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Link: https://lore.kernel.org/bpf/20231107045725.2278852-3-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Song Liu
|
74523c06ae |
bpf: Add __bpf_dynptr_data* for in kernel use
Different types of bpf dynptr have different internal data storage. Specifically, SKB and XDP type of dynptr may have non-continuous data. Therefore, it is not always safe to directly access dynptr->data. Add __bpf_dynptr_data and __bpf_dynptr_data_rw to replace direct access to dynptr->data. Update bpf_verify_pkcs7_signature to use __bpf_dynptr_data instead of dynptr->data. Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Vadim Fedorenko <vadim.fedorenko@linux.dev> Link: https://lore.kernel.org/bpf/20231107045725.2278852-2-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Florian Lehner
|
9b75dbeb36 |
bpf, lpm: Fix check prefixlen before walking trie
When looking up an element in LPM trie, the condition 'matchlen ==
trie->max_prefixlen' will never return true, if key->prefixlen is larger
than trie->max_prefixlen. Consequently all elements in the LPM trie will
be visited and no element is returned in the end.
To resolve this, check key->prefixlen first before walking the LPM trie.
Fixes:
|
|
|
Andrii Nakryiko
|
4621202adc |
bpf: generalize reg_set_min_max() to handle two sets of two registers
Change reg_set_min_max() to take FALSE/TRUE sets of two registers each, instead of assuming that we are always comparing to a constant. For now we still assume that right-hand side registers are constants (and make sure that's the case by swapping src/dst regs, if necessary), but subsequent patches will remove this limitation. reg_set_min_max() is now called unconditionally for any register comparison, so that might include pointer vs pointer. This makes it consistent with is_branch_taken() generality. But we currently only support adjustments based on SCALAR vs SCALAR comparisons, so reg_set_min_max() has to guard itself againts pointers. Taking two by two registers allows to further unify and simplify check_cond_jmp_op() logic. We utilize fake register for BPF_K conditional jump case, just like with is_branch_taken() part. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-18-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
811476e9cc |
bpf: prepare reg_set_min_max for second set of registers
Similarly to is_branch_taken()-related refactorings, start preparing reg_set_min_max() to handle more generic case of two non-const registers. Start with renaming arguments to accommodate later addition of second register as an input argument. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-17-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
4d345887d2 |
bpf: unify 32-bit and 64-bit is_branch_taken logic
Combine 32-bit and 64-bit is_branch_taken logic for SCALAR_VALUE registers. It makes it easier to see parallels between two domains (32-bit and 64-bit), and makes subsequent refactoring more straightforward. No functional changes. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-16-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
b74c2a842b |
bpf: generalize is_branch_taken to handle all conditional jumps in one place
Make is_branch_taken() a single entry point for branch pruning decision making, handling both pointer vs pointer, pointer vs scalar, and scalar vs scalar cases in one place. This also nicely cleans up check_cond_jmp_op(). Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-15-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
c697289efe |
bpf: move is_branch_taken() down
Move is_branch_taken() slightly down. In subsequent patched we'll need both flip_opcode() and is_pkt_ptr_branch_taken() for is_branch_taken(), but instead of sprinkling forward declarations around, it makes more sense to move is_branch_taken() lower below is_pkt_ptr_branch_taken(), and also keep it closer to very tightly related reg_set_min_max(), as they are two critical parts of the same SCALAR range tracking logic. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-14-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
c31534267c |
bpf: generalize is_branch_taken() to work with two registers
While still assuming that second register is a constant, generalize is_branch_taken-related code to accept two registers instead of register plus explicit constant value. This also, as a side effect, allows to simplify check_cond_jmp_op() by unifying BPF_K case with BPF_X case, for which we use a fake register to represent BPF_K's imm constant as a register. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://lore.kernel.org/r/20231102033759.2541186-13-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
c2a3ab0946 |
bpf: rename is_branch_taken reg arguments to prepare for the second one
Just taking mundane refactoring bits out into a separate patch. No functional changes. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://lore.kernel.org/r/20231102033759.2541186-12-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
9e314f5d86 |
bpf: drop knowledge-losing __reg_combine_{32,64}_into_{64,32} logic
When performing 32-bit conditional operation operating on lower 32 bits
of a full 64-bit register, register full value isn't changed. We just
potentially gain new knowledge about that register's lower 32 bits.
Unfortunately, __reg_combine_{32,64}_into_{64,32} logic that
reg_set_min_max() performs as a last step, can lose information in some
cases due to __mark_reg64_unbounded() and __reg_assign_32_into_64().
That's bad and completely unnecessary. Especially __reg_assign_32_into_64()
looks completely out of place here, because we are not performing
zero-extending subregister assignment during conditional jump.
So this patch replaced __reg_combine_* with just a normal
reg_bounds_sync() which will do a proper job of deriving u64/s64 bounds
from u32/s32, and vice versa (among all other combinations).
__reg_combine_64_into_32() is also used in one more place,
coerce_reg_to_size(), while handling 1- and 2-byte register loads.
Looking into this, it seems like besides marking subregister as
unbounded before performing reg_bounds_sync(), we were also performing
deduction of smin32/smax32 and umin32/umax32 bounds from respective
smin/smax and umin/umax bounds. It's now redundant as reg_bounds_sync()
performs all the same logic more generically (e.g., without unnecessary
assumption that upper 32 bits of full register should be zero).
Long story short, we remove __reg_combine_64_into_32() completely, and
coerce_reg_to_size() now only does resetting subreg to unbounded and then
performing reg_bounds_sync() to recover as much information as possible
from 64-bit umin/umax and smin/smax bounds, set explicitly in
coerce_reg_to_size() earlier.
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Link: https://lore.kernel.org/r/20231102033759.2541186-10-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Andrii Nakryiko
|
d7f0087381 |
bpf: try harder to deduce register bounds from different numeric domains
There are cases (caught by subsequent reg_bounds tests in selftests/bpf) where performing one round of __reg_deduce_bounds() doesn't propagate all the information from, say, s32 to u32 bounds and than from newly learned u32 bounds back to u64 and s64. So perform __reg_deduce_bounds() twice to make sure such derivations are propagated fully after reg_bounds_sync(). One such example is test `(s64)[0xffffffff00000001; 0] (u64)< 0xffffffff00000000` from selftest patch from this patch set. It demonstrates an intricate dance of u64 -> s64 -> u64 -> u32 bounds adjustments, which requires two rounds of __reg_deduce_bounds(). Here are corresponding refinement log from selftest, showing evolution of knowledge. REFINING (FALSE R1) (u64)SRC=[0xffffffff00000000; U64_MAX] (u64)DST_OLD=[0; U64_MAX] (u64)DST_NEW=[0xffffffff00000000; U64_MAX] REFINING (FALSE R1) (u64)SRC=[0xffffffff00000000; U64_MAX] (s64)DST_OLD=[0xffffffff00000001; 0] (s64)DST_NEW=[0xffffffff00000001; -1] REFINING (FALSE R1) (s64)SRC=[0xffffffff00000001; -1] (u64)DST_OLD=[0xffffffff00000000; U64_MAX] (u64)DST_NEW=[0xffffffff00000001; U64_MAX] REFINING (FALSE R1) (u64)SRC=[0xffffffff00000001; U64_MAX] (u32)DST_OLD=[0; U32_MAX] (u32)DST_NEW=[1; U32_MAX] R1 initially has smin/smax set to [0xffffffff00000001; -1], while umin/umax is unknown. After (u64)< comparison, in FALSE branch we gain knowledge that umin/umax is [0xffffffff00000000; U64_MAX]. That causes smin/smax to learn that zero can't happen and upper bound is -1. Then smin/smax is adjusted from umin/umax improving lower bound from 0xffffffff00000000 to 0xffffffff00000001. And then eventually umin32/umax32 bounds are drived from umin/umax and become [1; U32_MAX]. Selftest in the last patch is actually implementing a multi-round fixed-point convergence logic, but so far all the tests are handled by two rounds of reg_bounds_sync() on the verifier state, so we keep it simple for now. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-9-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
c51d5ad654 |
bpf: improve deduction of 64-bit bounds from 32-bit bounds
Add a few interesting cases in which we can tighten 64-bit bounds based on newly learnt information about 32-bit bounds. E.g., when full u64/s64 registers are used in BPF program, and then eventually compared as u32/s32. The latter comparison doesn't change the value of full register, but it does impose new restrictions on possible lower 32 bits of such full registers. And we can use that to derive additional full register bounds information. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Link: https://lore.kernel.org/r/20231102033759.2541186-8-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
6593f2e674 |
bpf: add special smin32/smax32 derivation from 64-bit bounds
Add a special case where we can derive valid s32 bounds from umin/umax or smin/smax by stitching together negative s32 subrange and non-negative s32 subrange. That requires upper 32 bits to form a [N, N+1] range in u32 domain (taking into account wrap around, so 0xffffffff to 0x00000000 is a valid [N, N+1] range in this sense). See code comment for concrete examples. Eduard Zingerman also provided an alternative explanation ([0]) for more mathematically inclined readers: Suppose: . there are numbers a, b, c . 2**31 <= b < 2**32 . 0 <= c < 2**31 . umin = 2**32 * a + b . umax = 2**32 * (a + 1) + c The number of values in the range represented by [umin; umax] is: . N = umax - umin + 1 = 2**32 + c - b + 1 . min(N) = 2**32 + 0 - (2**32-1) + 1 = 2, with b = 2**32-1, c = 0 . max(N) = 2**32 + (2**31 - 1) - 2**31 + 1 = 2**32, with b = 2**31, c = 2**31-1 Hence [(s32)b; (s32)c] forms a valid range. [0] https://lore.kernel.org/bpf/d7af631802f0cfae20df77fe70068702d24bbd31.camel@gmail.com/ Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-7-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
c1efab6468 |
bpf: derive subreg bounds from full bounds when upper 32 bits are constant
Comments in code try to explain the idea behind why this is correct. Please check the code and comments. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-6-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
d540517990 |
bpf: derive smin32/smax32 from umin32/umax32 bounds
All the logic that applies to u64 vs s64, equally applies for u32 vs s32 relationships (just taken in a smaller 32-bit numeric space). So do the same deduction of smin32/smax32 from umin32/umax32, if we can. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-5-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Andrii Nakryiko
|
93f7378734 |
bpf: derive smin/smax from umin/max bounds
Add smin/smax derivation from appropriate umin/umax values. Previously the logic was surprisingly asymmetric, trying to derive umin/umax from smin/smax (if possible), but not trying to do the same in the other direction. A simple addition to __reg64_deduce_bounds() fixes this. Added also generic comment about u64/s64 ranges and their relationship. Hopefully that helps readers to understand all the bounds deductions a bit better. Acked-by: Eduard Zingerman <eddyz87@gmail.com> Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20231102033759.2541186-4-andrii@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Chuyi Zhou
|
0de4f50de2 |
bpf: Let verifier consider {task,cgroup} is trusted in bpf_iter_reg
BTF_TYPE_SAFE_TRUSTED(struct bpf_iter__task) in verifier.c wanted to
teach BPF verifier that bpf_iter__task -> task is a trusted ptr. But it
doesn't work well.
The reason is, bpf_iter__task -> task would go through btf_ctx_access()
which enforces the reg_type of 'task' is ctx_arg_info->reg_type, and in
task_iter.c, we actually explicitly declare that the
ctx_arg_info->reg_type is PTR_TO_BTF_ID_OR_NULL.
Actually we have a previous case like this[1] where PTR_TRUSTED is added to
the arg flag for map_iter.
This patch sets ctx_arg_info->reg_type is PTR_TO_BTF_ID_OR_NULL |
PTR_TRUSTED in task_reg_info.
Similarly, bpf_cgroup_reg_info -> cgroup is also PTR_TRUSTED since we are
under the protection of cgroup_mutex and we would check cgroup_is_dead()
in __cgroup_iter_seq_show().
This patch is to improve the user experience of the newly introduced
bpf_iter_css_task kfunc before hitting the mainline. The Fixes tag is
pointing to the commit introduced the bpf_iter_css_task kfunc.
Link[1]:https://lore.kernel.org/all/20230706133932.45883-3-aspsk@isovalent.com/
Fixes:
|
|
|
Shung-Hsi Yu
|
291d044fd5 |
bpf: Fix precision tracking for BPF_ALU | BPF_TO_BE | BPF_END
BPF_END and BPF_NEG has a different specification for the source bit in
the opcode compared to other ALU/ALU64 instructions, and is either
reserved or use to specify the byte swap endianness. In both cases the
source bit does not encode source operand location, and src_reg is a
reserved field.
backtrack_insn() currently does not differentiate BPF_END and BPF_NEG
from other ALU/ALU64 instructions, which leads to r0 being incorrectly
marked as precise when processing BPF_ALU | BPF_TO_BE | BPF_END
instructions. This commit teaches backtrack_insn() to correctly mark
precision for such case.
While precise tracking of BPF_NEG and other BPF_END instructions are
correct and does not need fixing, this commit opt to process all BPF_NEG
and BPF_END instructions within the same if-clause to better align with
current convention used in the verifier (e.g. check_alu_op).
Fixes:
|
|
|
Chuyi Zhou
|
3091b66749 |
bpf: Relax allowlist for css_task iter
The newly added open-coded css_task iter would try to hold the global
css_set_lock in bpf_iter_css_task_new, so the bpf side has to be careful in
where it allows to use this iter. The mainly concern is dead locking on
css_set_lock. check_css_task_iter_allowlist() in verifier enforced css_task
can only be used in bpf_lsm hooks and sleepable bpf_iter.
This patch relax the allowlist for css_task iter. Any lsm and any iter
(even non-sleepable) and any sleepable are safe since they would not hold
the css_set_lock before entering BPF progs context.
This patch also fixes the misused BPF_TRACE_ITER in
check_css_task_iter_allowlist which compared bpf_prog_type with
bpf_attach_type.
Fixes:
|
|
|
Hou Tao
|
fd381ce60a |
bpf: Check map->usercnt after timer->timer is assigned
When there are concurrent uref release and bpf timer init operations,
the following sequence diagram is possible. It will break the guarantee
provided by bpf_timer: bpf_timer will still be alive after userspace
application releases or unpins the map. It also will lead to kmemleak
for old kernel version which doesn't release bpf_timer when map is
released.
bpf program X:
bpf_timer_init()
lock timer->lock
read timer->timer as NULL
read map->usercnt != 0
process Y:
close(map_fd)
// put last uref
bpf_map_put_uref()
atomic_dec_and_test(map->usercnt)
array_map_free_timers()
bpf_timer_cancel_and_free()
// just return
read timer->timer is NULL
t = bpf_map_kmalloc_node()
timer->timer = t
unlock timer->lock
Fix the problem by checking map->usercnt after timer->timer is assigned,
so when there are concurrent uref release and bpf timer init, either
bpf_timer_cancel_and_free() from uref release reads a no-NULL timer
or the newly-added atomic64_read() returns a zero usercnt.
Because atomic_dec_and_test(map->usercnt) and READ_ONCE(timer->timer)
in bpf_timer_cancel_and_free() are not protected by a lock, so add
a memory barrier to guarantee the order between map->usercnt and
timer->timer. Also use WRITE_ONCE(timer->timer, x) to match the lockless
read of timer->timer in bpf_timer_cancel_and_free().
Reported-by: Hsin-Wei Hung <hsinweih@uci.edu>
Closes: https://lore.kernel.org/bpf/CABcoxUaT2k9hWsS1tNgXyoU3E-=PuOgMn737qK984fbFmfYixQ@mail.gmail.com
Fixes:
|
|
|
Dave Marchevsky
|
391145ba2a |
bpf: Add __bpf_kfunc_{start,end}_defs macros
BPF kfuncs are meant to be called from BPF programs. Accordingly, most
kfuncs are not called from anywhere in the kernel, which the
-Wmissing-prototypes warning is unhappy about. We've peppered
__diag_ignore_all("-Wmissing-prototypes", ... everywhere kfuncs are
defined in the codebase to suppress this warning.
This patch adds two macros meant to bound one or many kfunc definitions.
All existing kfunc definitions which use these __diag calls to suppress
-Wmissing-prototypes are migrated to use the newly-introduced macros.
A new __diag_ignore_all - for "-Wmissing-declarations" - is added to the
__bpf_kfunc_start_defs macro based on feedback from Andrii on an earlier
version of this patch [0] and another recent mailing list thread [1].
In the future we might need to ignore different warnings or do other
kfunc-specific things. This change will make it easier to make such
modifications for all kfunc defs.
[0]: https://lore.kernel.org/bpf/CAEf4BzaE5dRWtK6RPLnjTW-MW9sx9K3Fn6uwqCTChK2Dcb1Xig@mail.gmail.com/
[1]: https://lore.kernel.org/bpf/ZT+2qCc%2FaXep0%2FLf@krava/
Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com>
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Cc: Jiri Olsa <olsajiri@gmail.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Link: https://lore.kernel.org/r/20231031215625.2343848-1-davemarchevsky@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Hao Sun
|
811c363645 |
bpf: Fix check_stack_write_fixed_off() to correctly spill imm
In check_stack_write_fixed_off(), imm value is cast to u32 before being
spilled to the stack. Therefore, the sign information is lost, and the
range information is incorrect when load from the stack again.
For the following prog:
0: r2 = r10
1: *(u64*)(r2 -40) = -44
2: r0 = *(u64*)(r2 - 40)
3: if r0 s<= 0xa goto +2
4: r0 = 1
5: exit
6: r0 = 0
7: exit
The verifier gives:
func#0 @0
0: R1=ctx(off=0,imm=0) R10=fp0
0: (bf) r2 = r10 ; R2_w=fp0 R10=fp0
1: (7a) *(u64 *)(r2 -40) = -44 ; R2_w=fp0 fp-40_w=4294967252
2: (79) r0 = *(u64 *)(r2 -40) ; R0_w=4294967252 R2_w=fp0
fp-40_w=4294967252
3: (c5) if r0 s< 0xa goto pc+2
mark_precise: frame0: last_idx 3 first_idx 0 subseq_idx -1
mark_precise: frame0: regs=r0 stack= before 2: (79) r0 = *(u64 *)(r2 -40)
3: R0_w=4294967252
4: (b7) r0 = 1 ; R0_w=1
5: (95) exit
verification time 7971 usec
stack depth 40
processed 6 insns (limit 1000000) max_states_per_insn 0 total_states 0
peak_states 0 mark_read 0
So remove the incorrect cast, since imm field is declared as s32, and
__mark_reg_known() takes u64, so imm would be correctly sign extended
by compiler.
Fixes:
|
|
Matthieu Baerts
|
05670f81d1 |
bpf: fix compilation error without CGROUPS
Our MPTCP CI complained [1] -- and KBuild too -- that it was no longer
possible to build the kernel without CONFIG_CGROUPS:
kernel/bpf/task_iter.c: In function 'bpf_iter_css_task_new':
kernel/bpf/task_iter.c:919:14: error: 'CSS_TASK_ITER_PROCS' undeclared (first use in this function)
919 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED:
| ^~~~~~~~~~~~~~~~~~~
kernel/bpf/task_iter.c:919:14: note: each undeclared identifier is reported only once for each function it appears in
kernel/bpf/task_iter.c:919:36: error: 'CSS_TASK_ITER_THREADED' undeclared (first use in this function)
919 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED:
| ^~~~~~~~~~~~~~~~~~~~~~
kernel/bpf/task_iter.c:927:60: error: invalid application of 'sizeof' to incomplete type 'struct css_task_iter'
927 | kit->css_it = bpf_mem_alloc(&bpf_global_ma, sizeof(struct css_task_iter));
| ^~~~~~
kernel/bpf/task_iter.c:930:9: error: implicit declaration of function 'css_task_iter_start'; did you mean 'task_seq_start'? [-Werror=implicit-function-declaration]
930 | css_task_iter_start(css, flags, kit->css_it);
| ^~~~~~~~~~~~~~~~~~~
| task_seq_start
kernel/bpf/task_iter.c: In function 'bpf_iter_css_task_next':
kernel/bpf/task_iter.c:940:16: error: implicit declaration of function 'css_task_iter_next'; did you mean 'class_dev_iter_next'? [-Werror=implicit-function-declaration]
940 | return css_task_iter_next(kit->css_it);
| ^~~~~~~~~~~~~~~~~~
| class_dev_iter_next
kernel/bpf/task_iter.c:940:16: error: returning 'int' from a function with return type 'struct task_struct *' makes pointer from integer without a cast [-Werror=int-conversion]
940 | return css_task_iter_next(kit->css_it);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
kernel/bpf/task_iter.c: In function 'bpf_iter_css_task_destroy':
kernel/bpf/task_iter.c:949:9: error: implicit declaration of function 'css_task_iter_end' [-Werror=implicit-function-declaration]
949 | css_task_iter_end(kit->css_it);
| ^~~~~~~~~~~~~~~~~
This patch simply surrounds with a #ifdef the new code requiring CGroups
support. It seems enough for the compiler and this is similar to
bpf_iter_css_{new,next,destroy}() functions where no other #ifdef have
been added in kernel/bpf/helpers.c and in the selftests.
Fixes:
|
|
|
Linus Torvalds
|
f5277ad1e9 |
for-6.7/io_uring-sockopt-2023-10-30
-----BEGIN PGP SIGNATURE-----
iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAmU/vdwQHGF4Ym9lQGtl
cm5lbC5kawAKCRD301j7KXHgpr2rD/0astIsj/AACVSPzHARg9lnhkIvUeweMSSl
CjifLTzK3a9E3R2IrC4sflObUKIEL3fste0Lva141eNULZvBJ6cQJDvY7Bp72Bkc
CTPEwEQiwDJKLhTzQh3gY0H0+nFMWwEm1uc4dyeNAft/R9bPP/qOq62ttCoCp9+S
1UoFmTlJE3bhejyS7fytoGZvKqhkpdR7rtbR4ya7CXWPoAG+v9amo8fputbxm0dj
WECpKdd65JHWwYV4rbPA69T7jZ9V0oUsLen9RJ9BmjMLOFggHYqQdvEwG0Htirhw
t5uaXqSvc8pXsJhKXMS3tXCrLNtBha5nlWHBpSE+6ovcmKiRzFjUaRXkRbcIrOAx
ljIm0HHto1+xv0pDrNl3/lIjv5dpNOEauqqgMeYytQJIHa0JpSWbYzvjwQ8EZXQv
WWDiRfH5Z0/3BsFdOCVqd8mTt4Pbksp2VFcxGkojRtSqSr4CML3mPZSmqGcs3nE6
Fc16XXw7oLEWoF1tQYMP6KG0cVLem4on28c8CcVMJ/pRvcun3jBCif2gmMHJkWyA
a6Uq116amqQ61f1p+EQ3ChqyTA5uALrXPmovu6Ne3Y/btW5yG4+Vu7AsPLjPHdFN
oGHjOPV77XQzEqzUWRXmXPecZ+QifkcCV/8kbqtEHQqk5n+HUKQZmpC8+014ms3V
Af6LYI/vYg==
=sk8+
-----END PGP SIGNATURE-----
Merge tag 'for-6.7/io_uring-sockopt-2023-10-30' of git://git.kernel.dk/linux
Pull io_uring {get,set}sockopt support from Jens Axboe:
"This adds support for using getsockopt and setsockopt via io_uring.
The main use cases for this is to enable use of direct descriptors,
rather than first instantiating a normal file descriptor, doing the
option tweaking needed, then turning it into a direct descriptor. With
this support, we can avoid needing a regular file descriptor
completely.
The net and bpf bits have been signed off on their side"
* tag 'for-6.7/io_uring-sockopt-2023-10-30' of git://git.kernel.dk/linux:
selftests/bpf/sockopt: Add io_uring support
io_uring/cmd: Introduce SOCKET_URING_OP_SETSOCKOPT
io_uring/cmd: Introduce SOCKET_URING_OP_GETSOCKOPT
io_uring/cmd: return -EOPNOTSUPP if net is disabled
selftests/net: Extract uring helpers to be reusable
tools headers: Grab copy of io_uring.h
io_uring/cmd: Pass compat mode in issue_flags
net/socket: Break down __sys_getsockopt
net/socket: Break down __sys_setsockopt
bpf: Add sockptr support for setsockopt
bpf: Add sockptr support for getsockopt
|
|
|
Linus Torvalds
|
89ed67ef12 |
Networking changes for 6.7.
Core & protocols
----------------
- Support usec resolution of TCP timestamps, enabled selectively by
a route attribute.
- Defer regular TCP ACK while processing socket backlog, try to send
a cumulative ACK at the end. Increase single TCP flow performance
on a 200Gbit NIC by 20% (100Gbit -> 120Gbit).
- The Fair Queuing (FQ) packet scheduler:
- add built-in 3 band prio / WRR scheduling
- support bypass if the qdisc is mostly idle (5% speed up for TCP RR)
- improve inactive flow reporting
- optimize the layout of structures for better cache locality
- Support TCP Authentication Option (RFC 5925, TCP-AO), a more modern
replacement for the old MD5 option.
- Add more retransmission timeout (RTO) related statistics to TCP_INFO.
- Support sending fragmented skbs over vsock sockets.
- Make sure we send SIGPIPE for vsock sockets if socket was shutdown().
- Add sysctl for ignoring lower limit on lifetime in Router
Advertisement PIO, based on an in-progress IETF draft.
- Add sysctl to control activation of TCP ping-pong mode.
- Add sysctl to make connection timeout in MPTCP configurable.
- Support rcvlowat and notsent_lowat on MPTCP sockets, to help apps
limit the number of wakeups.
- Support netlink GET for MDB (multicast forwarding), allowing user
space to request a single MDB entry instead of dumping the entire
table.
- Support selective FDB flushing in the VXLAN tunnel driver.
- Allow limiting learned FDB entries in bridges, prevent OOM attacks.
- Allow controlling via configfs netconsole targets which were created
via the kernel cmdline at boot, rather than via configfs at runtime.
- Support multiple PTP timestamp event queue readers with different
filters.
- MCTP over I3C.
BPF
---
- Add new veth-like netdevice where BPF program defines the logic
of the xmit routine. It can operate in L3 and L2 mode.
- Support exceptions - allow asserting conditions which should
never be true but are hard for the verifier to infer.
With some extra flexibility around handling of the exit / failure.
https://lwn.net/Articles/938435/
- Add support for local per-cpu kptr, allow allocating and storing
per-cpu objects in maps. Access to those objects operates on
the value for the current CPU. This allows to deprecate local
one-off implementations of per-CPU storage like
BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE maps.
- Extend cgroup BPF sockaddr hooks for UNIX sockets. The use case is
for systemd to re-implement the LogNamespace feature which allows
running multiple instances of systemd-journald to process the logs
of different services.
- Enable open-coded task_vma iteration, after maple tree conversion
made it hard to directly walk VMAs in tracing programs.
- Add open-coded task, css_task and css iterator support.
One of the use cases is customizable OOM victim selection via BPF.
- Allow source address selection with bpf_*_fib_lookup().
- Add ability to pin BPF timer to the current CPU.
- Prevent creation of infinite loops by combining tail calls and
fentry/fexit programs.
- Add missed stats for kprobes to retrieve the number of missed kprobe
executions and subsequent executions of BPF programs.
- Inherit system settings for CPU security mitigations.
- Add BPF v4 CPU instruction support for arm32 and s390x.
Changes to common code
----------------------
- overflow: add DEFINE_FLEX() for on-stack definition of structs
with flexible array members.
- Process doc update with more guidance for reviewers.
Driver API
----------
- Simplify locking in WiFi (cfg80211 and mac80211 layers), use wiphy
mutex in most places and remove a lot of smaller locks.
- Create a common DPLL configuration API. Allow configuring
and querying state of PLL circuits used for clock syntonization,
in network time distribution.
- Unify fragmented and full page allocation APIs in page pool code.
Let drivers be ignorant of PAGE_SIZE.
- Rework PHY state machine to avoid races with calls to phy_stop().
- Notify DSA drivers of MAC address changes on user ports, improve
correctness of offloads which depend on matching port MAC addresses.
- Allow antenna control on injected WiFi frames.
- Reduce the number of variants of napi_schedule().
- Simplify error handling when composing devlink health messages.
Misc
----
- A lot of KCSAN data race "fixes", from Eric.
- A lot of __counted_by() annotations, from Kees.
- A lot of strncpy -> strscpy and printf format fixes.
- Replace master/slave terminology with conduit/user in DSA drivers.
- Handful of KUnit tests for netdev and WiFi core.
Removed
-------
- AppleTalk COPS.
- AppleTalk ipddp.
- TI AR7 CPMAC Ethernet driver.
Drivers
-------
- Ethernet high-speed NICs:
- Intel (100G, ice, idpf):
- add a driver for the Intel E2000 IPUs
- make CRC/FCS stripping configurable
- cross-timestamping for E823 devices
- basic support for E830 devices
- use aux-bus for managing client drivers
- i40e: report firmware versions via devlink
- nVidia/Mellanox:
- support 4-port NICs
- increase max number of channels to 256
- optimize / parallelize SF creation flow
- Broadcom (bnxt):
- enhance NIC temperature reporting
- support PAM4 speeds and lane configuration
- Marvell OcteonTX2:
- PTP pulse-per-second output support
- enable hardware timestamping for VFs
- Solarflare/AMD:
- conntrack NAT offload and offload for tunnels
- Wangxun (ngbe/txgbe):
- expose HW statistics
- Pensando/AMD:
- support PCI level reset
- narrow down the condition under which skbs are linearized
- Netronome/Corigine (nfp):
- support CHACHA20-POLY1305 crypto in IPsec offload
- Ethernet NICs embedded, slower, virtual:
- Synopsys (stmmac):
- add Loongson-1 SoC support
- enable use of HW queues with no offload capabilities
- enable PPS input support on all 5 channels
- increase TX coalesce timer to 5ms
- RealTek USB (r8152): improve efficiency of Rx by using GRO frags
- xen: support SW packet timestamping
- add drivers for implementations based on TI's PRUSS (AM64x EVM)
- nVidia/Mellanox Ethernet datacenter switches:
- avoid poor HW resource use on Spectrum-4 by better block selection
for IPv6 multicast forwarding and ordering of blocks in ACL region
- Ethernet embedded switches:
- Microchip:
- support configuring the drive strength for EMI compliance
- ksz9477: partial ACL support
- ksz9477: HSR offload
- ksz9477: Wake on LAN
- Realtek:
- rtl8366rb: respect device tree config of the CPU port
- Ethernet PHYs:
- support Broadcom BCM5221 PHYs
- TI dp83867: support hardware LED blinking
- CAN:
- add support for Linux-PHY based CAN transceivers
- at91_can: clean up and use rx-offload helpers
- WiFi:
- MediaTek (mt76):
- new sub-driver for mt7925 USB/PCIe devices
- HW wireless <> Ethernet bridging in MT7988 chips
- mt7603/mt7628 stability improvements
- Qualcomm (ath12k):
- WCN7850:
- enable 320 MHz channels in 6 GHz band
- hardware rfkill support
- enable IEEE80211_HW_SINGLE_SCAN_ON_ALL_BANDS
to make scan faster
- read board data variant name from SMBIOS
- QCN9274: mesh support
- RealTek (rtw89):
- TDMA-based multi-channel concurrency (MCC)
- Silicon Labs (wfx):
- Remain-On-Channel (ROC) support
- Bluetooth:
- ISO: many improvements for broadcast support
- mark BCM4378/BCM4387 as BROKEN_LE_CODED
- add support for QCA2066
- btmtksdio: enable Bluetooth wakeup from suspend
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=46nS
-----END PGP SIGNATURE-----
Merge tag 'net-next-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
"Core & protocols:
- Support usec resolution of TCP timestamps, enabled selectively by a
route attribute.
- Defer regular TCP ACK while processing socket backlog, try to send
a cumulative ACK at the end. Increase single TCP flow performance
on a 200Gbit NIC by 20% (100Gbit -> 120Gbit).
- The Fair Queuing (FQ) packet scheduler:
- add built-in 3 band prio / WRR scheduling
- support bypass if the qdisc is mostly idle (5% speed up for TCP RR)
- improve inactive flow reporting
- optimize the layout of structures for better cache locality
- Support TCP Authentication Option (RFC 5925, TCP-AO), a more modern
replacement for the old MD5 option.
- Add more retransmission timeout (RTO) related statistics to
TCP_INFO.
- Support sending fragmented skbs over vsock sockets.
- Make sure we send SIGPIPE for vsock sockets if socket was
shutdown().
- Add sysctl for ignoring lower limit on lifetime in Router
Advertisement PIO, based on an in-progress IETF draft.
- Add sysctl to control activation of TCP ping-pong mode.
- Add sysctl to make connection timeout in MPTCP configurable.
- Support rcvlowat and notsent_lowat on MPTCP sockets, to help apps
limit the number of wakeups.
- Support netlink GET for MDB (multicast forwarding), allowing user
space to request a single MDB entry instead of dumping the entire
table.
- Support selective FDB flushing in the VXLAN tunnel driver.
- Allow limiting learned FDB entries in bridges, prevent OOM attacks.
- Allow controlling via configfs netconsole targets which were
created via the kernel cmdline at boot, rather than via configfs at
runtime.
- Support multiple PTP timestamp event queue readers with different
filters.
- MCTP over I3C.
BPF:
- Add new veth-like netdevice where BPF program defines the logic of
the xmit routine. It can operate in L3 and L2 mode.
- Support exceptions - allow asserting conditions which should never
be true but are hard for the verifier to infer. With some extra
flexibility around handling of the exit / failure:
https://lwn.net/Articles/938435/
- Add support for local per-cpu kptr, allow allocating and storing
per-cpu objects in maps. Access to those objects operates on the
value for the current CPU.
This allows to deprecate local one-off implementations of per-CPU
storage like BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE maps.
- Extend cgroup BPF sockaddr hooks for UNIX sockets. The use case is
for systemd to re-implement the LogNamespace feature which allows
running multiple instances of systemd-journald to process the logs
of different services.
- Enable open-coded task_vma iteration, after maple tree conversion
made it hard to directly walk VMAs in tracing programs.
- Add open-coded task, css_task and css iterator support. One of the
use cases is customizable OOM victim selection via BPF.
- Allow source address selection with bpf_*_fib_lookup().
- Add ability to pin BPF timer to the current CPU.
- Prevent creation of infinite loops by combining tail calls and
fentry/fexit programs.
- Add missed stats for kprobes to retrieve the number of missed
kprobe executions and subsequent executions of BPF programs.
- Inherit system settings for CPU security mitigations.
- Add BPF v4 CPU instruction support for arm32 and s390x.
Changes to common code:
- overflow: add DEFINE_FLEX() for on-stack definition of structs with
flexible array members.
- Process doc update with more guidance for reviewers.
Driver API:
- Simplify locking in WiFi (cfg80211 and mac80211 layers), use wiphy
mutex in most places and remove a lot of smaller locks.
- Create a common DPLL configuration API. Allow configuring and
querying state of PLL circuits used for clock syntonization, in
network time distribution.
- Unify fragmented and full page allocation APIs in page pool code.
Let drivers be ignorant of PAGE_SIZE.
- Rework PHY state machine to avoid races with calls to phy_stop().
- Notify DSA drivers of MAC address changes on user ports, improve
correctness of offloads which depend on matching port MAC
addresses.
- Allow antenna control on injected WiFi frames.
- Reduce the number of variants of napi_schedule().
- Simplify error handling when composing devlink health messages.
Misc:
- A lot of KCSAN data race "fixes", from Eric.
- A lot of __counted_by() annotations, from Kees.
- A lot of strncpy -> strscpy and printf format fixes.
- Replace master/slave terminology with conduit/user in DSA drivers.
- Handful of KUnit tests for netdev and WiFi core.
Removed:
- AppleTalk COPS.
- AppleTalk ipddp.
- TI AR7 CPMAC Ethernet driver.
Drivers:
- Ethernet high-speed NICs:
- Intel (100G, ice, idpf):
- add a driver for the Intel E2000 IPUs
- make CRC/FCS stripping configurable
- cross-timestamping for E823 devices
- basic support for E830 devices
- use aux-bus for managing client drivers
- i40e: report firmware versions via devlink
- nVidia/Mellanox:
- support 4-port NICs
- increase max number of channels to 256
- optimize / parallelize SF creation flow
- Broadcom (bnxt):
- enhance NIC temperature reporting
- support PAM4 speeds and lane configuration
- Marvell OcteonTX2:
- PTP pulse-per-second output support
- enable hardware timestamping for VFs
- Solarflare/AMD:
- conntrack NAT offload and offload for tunnels
- Wangxun (ngbe/txgbe):
- expose HW statistics
- Pensando/AMD:
- support PCI level reset
- narrow down the condition under which skbs are linearized
- Netronome/Corigine (nfp):
- support CHACHA20-POLY1305 crypto in IPsec offload
- Ethernet NICs embedded, slower, virtual:
- Synopsys (stmmac):
- add Loongson-1 SoC support
- enable use of HW queues with no offload capabilities
- enable PPS input support on all 5 channels
- increase TX coalesce timer to 5ms
- RealTek USB (r8152): improve efficiency of Rx by using GRO frags
- xen: support SW packet timestamping
- add drivers for implementations based on TI's PRUSS (AM64x EVM)
- nVidia/Mellanox Ethernet datacenter switches:
- avoid poor HW resource use on Spectrum-4 by better block
selection for IPv6 multicast forwarding and ordering of blocks
in ACL region
- Ethernet embedded switches:
- Microchip:
- support configuring the drive strength for EMI compliance
- ksz9477: partial ACL support
- ksz9477: HSR offload
- ksz9477: Wake on LAN
- Realtek:
- rtl8366rb: respect device tree config of the CPU port
- Ethernet PHYs:
- support Broadcom BCM5221 PHYs
- TI dp83867: support hardware LED blinking
- CAN:
- add support for Linux-PHY based CAN transceivers
- at91_can: clean up and use rx-offload helpers
- WiFi:
- MediaTek (mt76):
- new sub-driver for mt7925 USB/PCIe devices
- HW wireless <> Ethernet bridging in MT7988 chips
- mt7603/mt7628 stability improvements
- Qualcomm (ath12k):
- WCN7850:
- enable 320 MHz channels in 6 GHz band
- hardware rfkill support
- enable IEEE80211_HW_SINGLE_SCAN_ON_ALL_BANDS to
make scan faster
- read board data variant name from SMBIOS
- QCN9274: mesh support
- RealTek (rtw89):
- TDMA-based multi-channel concurrency (MCC)
- Silicon Labs (wfx):
- Remain-On-Channel (ROC) support
- Bluetooth:
- ISO: many improvements for broadcast support
- mark BCM4378/BCM4387 as BROKEN_LE_CODED
- add support for QCA2066
- btmtksdio: enable Bluetooth wakeup from suspend"
* tag 'net-next-6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1816 commits)
net: pcs: xpcs: Add 2500BASE-X case in get state for XPCS drivers
net: bpf: Use sockopt_lock_sock() in ip_sock_set_tos()
net: mana: Use xdp_set_features_flag instead of direct assignment
vxlan: Cleanup IFLA_VXLAN_PORT_RANGE entry in vxlan_get_size()
iavf: delete the iavf client interface
iavf: add a common function for undoing the interrupt scheme
iavf: use unregister_netdev
iavf: rely on netdev's own registered state
iavf: fix the waiting time for initial reset
iavf: in iavf_down, don't queue watchdog_task if comms failed
iavf: simplify mutex_trylock+sleep loops
iavf: fix comments about old bit locks
doc/netlink: Update schema to support cmd-cnt-name and cmd-max-name
tools: ynl: introduce option to process unknown attributes or types
ipvlan: properly track tx_errors
netdevsim: Block until all devices are released
nfp: using napi_build_skb() to replace build_skb()
net: dsa: microchip: ksz9477: Fix spelling mistake "Enery" -> "Energy"
net: dsa: microchip: Ensure Stable PME Pin State for Wake-on-LAN
net: dsa: microchip: Refactor switch shutdown routine for WoL preparation
...
|
|
|
Linus Torvalds
|
14ab6d425e |
vfs-6.7.ctime
-----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCZTppYgAKCRCRxhvAZXjc okIHAP9anLz1QDyMLH12ASuHjgBc0Of3jcB6NB97IWGpL4O21gEA46ohaD+vcJuC YkBLU3lXqQ87nfu28ExFAzh10hG2jwM= =m4pB -----END PGP SIGNATURE----- Merge tag 'vfs-6.7.ctime' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs Pull vfs inode time accessor updates from Christian Brauner: "This finishes the conversion of all inode time fields to accessor functions as discussed on list. Changing timestamps manually as we used to do before is error prone. Using accessors function makes this robust. It does not contain the switch of the time fields to discrete 64 bit integers to replace struct timespec and free up space in struct inode. But after this, the switch can be trivially made and the patch should only affect the vfs if we decide to do it" * tag 'vfs-6.7.ctime' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (86 commits) fs: rename inode i_atime and i_mtime fields security: convert to new timestamp accessors selinux: convert to new timestamp accessors apparmor: convert to new timestamp accessors sunrpc: convert to new timestamp accessors mm: convert to new timestamp accessors bpf: convert to new timestamp accessors ipc: convert to new timestamp accessors linux: convert to new timestamp accessors zonefs: convert to new timestamp accessors xfs: convert to new timestamp accessors vboxsf: convert to new timestamp accessors ufs: convert to new timestamp accessors udf: convert to new timestamp accessors ubifs: convert to new timestamp accessors tracefs: convert to new timestamp accessors sysv: convert to new timestamp accessors squashfs: convert to new timestamp accessors server: convert to new timestamp accessors client: convert to new timestamp accessors ... |