mirror of https://github.com/torvalds/linux.git
386 Commits
| Author | SHA1 | Message | Date |
|---|---|---|---|
Toke Høiland-Jørgensen
|
1c123c567f |
bpf: Resolve fext program type when checking map compatibility
The bpf_prog_map_compatible() check makes sure that BPF program types are
not mixed inside BPF map types that can contain programs (tail call maps,
cpumaps and devmaps). It does this by setting the fields of the map->owner
struct to the values of the first program being checked against, and
rejecting any subsequent programs if the values don't match.
One of the values being set in the map owner struct is the program type,
and since the code did not resolve the prog type for fext programs, the map
owner type would be set to PROG_TYPE_EXT and subsequent loading of programs
of the target type into the map would fail.
This bug is seen in particular for XDP programs that are loaded as
PROG_TYPE_EXT using libxdp; these cannot insert programs into devmaps and
cpumaps because the check fails as described above.
Fix the bug by resolving the fext program type to its target program type
as elsewhere in the verifier.
v3:
- Add Yonghong's ACK
Fixes:
|
|
Linus Torvalds
|
7e68dd7d07 |
Networking changes for 6.2.
Core
----
- Allow live renaming when an interface is up
- Add retpoline wrappers for tc, improving considerably the
performances of complex queue discipline configurations.
- Add inet drop monitor support.
- A few GRO performance improvements.
- Add infrastructure for atomic dev stats, addressing long standing
data races.
- De-duplicate common code between OVS and conntrack offloading
infrastructure.
- A bunch of UBSAN_BOUNDS/FORTIFY_SOURCE improvements.
- Netfilter: introduce packet parser for tunneled packets
- Replace IPVS timer-based estimators with kthreads to scale up
the workload with the number of available CPUs.
- Add the helper support for connection-tracking OVS offload.
BPF
---
- Support for user defined BPF objects: the use case is to allocate
own objects, build own object hierarchies and use the building
blocks to build own data structures flexibly, for example, linked
lists in BPF.
- Make cgroup local storage available to non-cgroup attached BPF
programs.
- Avoid unnecessary deadlock detection and failures wrt BPF task
storage helpers.
- A relevant bunch of BPF verifier fixes and improvements.
- Veristat tool improvements to support custom filtering, sorting,
and replay of results.
- Add LLVM disassembler as default library for dumping JITed code.
- Lots of new BPF documentation for various BPF maps.
- Add bpf_rcu_read_{,un}lock() support for sleepable programs.
- Add RCU grace period chaining to BPF to wait for the completion
of access from both sleepable and non-sleepable BPF programs.
- Add support storing struct task_struct objects as kptrs in maps.
- Improve helper UAPI by explicitly defining BPF_FUNC_xxx integer
values.
- Add libbpf *_opts API-variants for bpf_*_get_fd_by_id() functions.
Protocols
---------
- TCP: implement Protective Load Balancing across switch links.
- TCP: allow dynamically disabling TCP-MD5 static key, reverting
back to fast[er]-path.
- UDP: Introduce optional per-netns hash lookup table.
- IPv6: simplify and cleanup sockets disposal.
- Netlink: support different type policies for each generic
netlink operation.
- MPTCP: add MSG_FASTOPEN and FastOpen listener side support.
- MPTCP: add netlink notification support for listener sockets
events.
- SCTP: add VRF support, allowing sctp sockets binding to VRF
devices.
- Add bridging MAC Authentication Bypass (MAB) support.
- Extensions for Ethernet VPN bridging implementation to better
support multicast scenarios.
- More work for Wi-Fi 7 support, comprising conversion of all
the existing drivers to internal TX queue usage.
- IPSec: introduce a new offload type (packet offload) allowing
complete header processing and crypto offloading.
- IPSec: extended ack support for more descriptive XFRM error
reporting.
- RXRPC: increase SACK table size and move processing into a
per-local endpoint kernel thread, reducing considerably the
required locking.
- IEEE 802154: synchronous send frame and extended filtering
support, initial support for scanning available 15.4 networks.
- Tun: bump the link speed from 10Mbps to 10Gbps.
- Tun/VirtioNet: implement UDP segmentation offload support.
Driver API
----------
- PHY/SFP: improve power level switching between standard
level 1 and the higher power levels.
- New API for netdev <-> devlink_port linkage.
- PTP: convert existing drivers to new frequency adjustment
implementation.
- DSA: add support for rx offloading.
- Autoload DSA tagging driver when dynamically changing protocol.
- Add new PCP and APPTRUST attributes to Data Center Bridging.
- Add configuration support for 800Gbps link speed.
- Add devlink port function attribute to enable/disable RoCE and
migratable.
- Extend devlink-rate to support strict prioriry and weighted fair
queuing.
- Add devlink support to directly reading from region memory.
- New device tree helper to fetch MAC address from nvmem.
- New big TCP helper to simplify temporary header stripping.
New hardware / drivers
----------------------
- Ethernet:
- Marvel Octeon CNF95N and CN10KB Ethernet Switches.
- Marvel Prestera AC5X Ethernet Switch.
- WangXun 10 Gigabit NIC.
- Motorcomm yt8521 Gigabit Ethernet.
- Microchip ksz9563 Gigabit Ethernet Switch.
- Microsoft Azure Network Adapter.
- Linux Automation 10Base-T1L adapter.
- PHY:
- Aquantia AQR112 and AQR412.
- Motorcomm YT8531S.
- PTP:
- Orolia ART-CARD.
- WiFi:
- MediaTek Wi-Fi 7 (802.11be) devices.
- RealTek rtw8821cu, rtw8822bu, rtw8822cu and rtw8723du USB
devices.
- Bluetooth:
- Broadcom BCM4377/4378/4387 Bluetooth chipsets.
- Realtek RTL8852BE and RTL8723DS.
- Cypress.CYW4373A0 WiFi + Bluetooth combo device.
Drivers
-------
- CAN:
- gs_usb: bus error reporting support.
- kvaser_usb: listen only and bus error reporting support.
- Ethernet NICs:
- Intel (100G):
- extend action skbedit to RX queue mapping.
- implement devlink-rate support.
- support direct read from memory.
- nVidia/Mellanox (mlx5):
- SW steering improvements, increasing rules update rate.
- Support for enhanced events compression.
- extend H/W offload packet manipulation capabilities.
- implement IPSec packet offload mode.
- nVidia/Mellanox (mlx4):
- better big TCP support.
- Netronome Ethernet NICs (nfp):
- IPsec offload support.
- add support for multicast filter.
- Broadcom:
- RSS and PTP support improvements.
- AMD/SolarFlare:
- netlink extened ack improvements.
- add basic flower matches to offload, and related stats.
- Virtual NICs:
- ibmvnic: introduce affinity hint support.
- small / embedded:
- FreeScale fec: add initial XDP support.
- Marvel mv643xx_eth: support MII/GMII/RGMII modes for Kirkwood.
- TI am65-cpsw: add suspend/resume support.
- Mediatek MT7986: add RX wireless wthernet dispatch support.
- Realtek 8169: enable GRO software interrupt coalescing per
default.
- Ethernet high-speed switches:
- Microchip (sparx5):
- add support for Sparx5 TC/flower H/W offload via VCAP.
- Mellanox mlxsw:
- add 802.1X and MAC Authentication Bypass offload support.
- add ip6gre support.
- Embedded Ethernet switches:
- Mediatek (mtk_eth_soc):
- improve PCS implementation, add DSA untag support.
- enable flow offload support.
- Renesas:
- add rswitch R-Car Gen4 gPTP support.
- Microchip (lan966x):
- add full XDP support.
- add TC H/W offload via VCAP.
- enable PTP on bridge interfaces.
- Microchip (ksz8):
- add MTU support for KSZ8 series.
- Qualcomm 802.11ax WiFi (ath11k):
- support configuring channel dwell time during scan.
- MediaTek WiFi (mt76):
- enable Wireless Ethernet Dispatch (WED) offload support.
- add ack signal support.
- enable coredump support.
- remain_on_channel support.
- Intel WiFi (iwlwifi):
- enable Wi-Fi 7 Extremely High Throughput (EHT) PHY capabilities.
- 320 MHz channels support.
- RealTek WiFi (rtw89):
- new dynamic header firmware format support.
- wake-over-WLAN support.
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
-----BEGIN PGP SIGNATURE-----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=CbJC
-----END PGP SIGNATURE-----
Merge tag 'net-next-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Paolo Abeni:
"Core:
- Allow live renaming when an interface is up
- Add retpoline wrappers for tc, improving considerably the
performances of complex queue discipline configurations
- Add inet drop monitor support
- A few GRO performance improvements
- Add infrastructure for atomic dev stats, addressing long standing
data races
- De-duplicate common code between OVS and conntrack offloading
infrastructure
- A bunch of UBSAN_BOUNDS/FORTIFY_SOURCE improvements
- Netfilter: introduce packet parser for tunneled packets
- Replace IPVS timer-based estimators with kthreads to scale up the
workload with the number of available CPUs
- Add the helper support for connection-tracking OVS offload
BPF:
- Support for user defined BPF objects: the use case is to allocate
own objects, build own object hierarchies and use the building
blocks to build own data structures flexibly, for example, linked
lists in BPF
- Make cgroup local storage available to non-cgroup attached BPF
programs
- Avoid unnecessary deadlock detection and failures wrt BPF task
storage helpers
- A relevant bunch of BPF verifier fixes and improvements
- Veristat tool improvements to support custom filtering, sorting,
and replay of results
- Add LLVM disassembler as default library for dumping JITed code
- Lots of new BPF documentation for various BPF maps
- Add bpf_rcu_read_{,un}lock() support for sleepable programs
- Add RCU grace period chaining to BPF to wait for the completion of
access from both sleepable and non-sleepable BPF programs
- Add support storing struct task_struct objects as kptrs in maps
- Improve helper UAPI by explicitly defining BPF_FUNC_xxx integer
values
- Add libbpf *_opts API-variants for bpf_*_get_fd_by_id() functions
Protocols:
- TCP: implement Protective Load Balancing across switch links
- TCP: allow dynamically disabling TCP-MD5 static key, reverting back
to fast[er]-path
- UDP: Introduce optional per-netns hash lookup table
- IPv6: simplify and cleanup sockets disposal
- Netlink: support different type policies for each generic netlink
operation
- MPTCP: add MSG_FASTOPEN and FastOpen listener side support
- MPTCP: add netlink notification support for listener sockets events
- SCTP: add VRF support, allowing sctp sockets binding to VRF devices
- Add bridging MAC Authentication Bypass (MAB) support
- Extensions for Ethernet VPN bridging implementation to better
support multicast scenarios
- More work for Wi-Fi 7 support, comprising conversion of all the
existing drivers to internal TX queue usage
- IPSec: introduce a new offload type (packet offload) allowing
complete header processing and crypto offloading
- IPSec: extended ack support for more descriptive XFRM error
reporting
- RXRPC: increase SACK table size and move processing into a
per-local endpoint kernel thread, reducing considerably the
required locking
- IEEE 802154: synchronous send frame and extended filtering support,
initial support for scanning available 15.4 networks
- Tun: bump the link speed from 10Mbps to 10Gbps
- Tun/VirtioNet: implement UDP segmentation offload support
Driver API:
- PHY/SFP: improve power level switching between standard level 1 and
the higher power levels
- New API for netdev <-> devlink_port linkage
- PTP: convert existing drivers to new frequency adjustment
implementation
- DSA: add support for rx offloading
- Autoload DSA tagging driver when dynamically changing protocol
- Add new PCP and APPTRUST attributes to Data Center Bridging
- Add configuration support for 800Gbps link speed
- Add devlink port function attribute to enable/disable RoCE and
migratable
- Extend devlink-rate to support strict prioriry and weighted fair
queuing
- Add devlink support to directly reading from region memory
- New device tree helper to fetch MAC address from nvmem
- New big TCP helper to simplify temporary header stripping
New hardware / drivers:
- Ethernet:
- Marvel Octeon CNF95N and CN10KB Ethernet Switches
- Marvel Prestera AC5X Ethernet Switch
- WangXun 10 Gigabit NIC
- Motorcomm yt8521 Gigabit Ethernet
- Microchip ksz9563 Gigabit Ethernet Switch
- Microsoft Azure Network Adapter
- Linux Automation 10Base-T1L adapter
- PHY:
- Aquantia AQR112 and AQR412
- Motorcomm YT8531S
- PTP:
- Orolia ART-CARD
- WiFi:
- MediaTek Wi-Fi 7 (802.11be) devices
- RealTek rtw8821cu, rtw8822bu, rtw8822cu and rtw8723du USB
devices
- Bluetooth:
- Broadcom BCM4377/4378/4387 Bluetooth chipsets
- Realtek RTL8852BE and RTL8723DS
- Cypress.CYW4373A0 WiFi + Bluetooth combo device
Drivers:
- CAN:
- gs_usb: bus error reporting support
- kvaser_usb: listen only and bus error reporting support
- Ethernet NICs:
- Intel (100G):
- extend action skbedit to RX queue mapping
- implement devlink-rate support
- support direct read from memory
- nVidia/Mellanox (mlx5):
- SW steering improvements, increasing rules update rate
- Support for enhanced events compression
- extend H/W offload packet manipulation capabilities
- implement IPSec packet offload mode
- nVidia/Mellanox (mlx4):
- better big TCP support
- Netronome Ethernet NICs (nfp):
- IPsec offload support
- add support for multicast filter
- Broadcom:
- RSS and PTP support improvements
- AMD/SolarFlare:
- netlink extened ack improvements
- add basic flower matches to offload, and related stats
- Virtual NICs:
- ibmvnic: introduce affinity hint support
- small / embedded:
- FreeScale fec: add initial XDP support
- Marvel mv643xx_eth: support MII/GMII/RGMII modes for Kirkwood
- TI am65-cpsw: add suspend/resume support
- Mediatek MT7986: add RX wireless wthernet dispatch support
- Realtek 8169: enable GRO software interrupt coalescing per
default
- Ethernet high-speed switches:
- Microchip (sparx5):
- add support for Sparx5 TC/flower H/W offload via VCAP
- Mellanox mlxsw:
- add 802.1X and MAC Authentication Bypass offload support
- add ip6gre support
- Embedded Ethernet switches:
- Mediatek (mtk_eth_soc):
- improve PCS implementation, add DSA untag support
- enable flow offload support
- Renesas:
- add rswitch R-Car Gen4 gPTP support
- Microchip (lan966x):
- add full XDP support
- add TC H/W offload via VCAP
- enable PTP on bridge interfaces
- Microchip (ksz8):
- add MTU support for KSZ8 series
- Qualcomm 802.11ax WiFi (ath11k):
- support configuring channel dwell time during scan
- MediaTek WiFi (mt76):
- enable Wireless Ethernet Dispatch (WED) offload support
- add ack signal support
- enable coredump support
- remain_on_channel support
- Intel WiFi (iwlwifi):
- enable Wi-Fi 7 Extremely High Throughput (EHT) PHY capabilities
- 320 MHz channels support
- RealTek WiFi (rtw89):
- new dynamic header firmware format support
- wake-over-WLAN support"
* tag 'net-next-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2002 commits)
ipvs: fix type warning in do_div() on 32 bit
net: lan966x: Remove a useless test in lan966x_ptp_add_trap()
net: ipa: add IPA v4.7 support
dt-bindings: net: qcom,ipa: Add SM6350 compatible
bnxt: Use generic HBH removal helper in tx path
IPv6/GRO: generic helper to remove temporary HBH/jumbo header in driver
selftests: forwarding: Add bridge MDB test
selftests: forwarding: Rename bridge_mdb test
bridge: mcast: Support replacement of MDB port group entries
bridge: mcast: Allow user space to specify MDB entry routing protocol
bridge: mcast: Allow user space to add (*, G) with a source list and filter mode
bridge: mcast: Add support for (*, G) with a source list and filter mode
bridge: mcast: Avoid arming group timer when (S, G) corresponds to a source
bridge: mcast: Add a flag for user installed source entries
bridge: mcast: Expose __br_multicast_del_group_src()
bridge: mcast: Expose br_multicast_new_group_src()
bridge: mcast: Add a centralized error path
bridge: mcast: Place netlink policy before validation functions
bridge: mcast: Split (*, G) and (S, G) addition into different functions
bridge: mcast: Do not derive entry type from its filter mode
...
|
|
Kumar Kartikeya Dwivedi
|
958cf2e273 |
bpf: Introduce bpf_obj_new
Introduce type safe memory allocator bpf_obj_new for BPF programs. The
kernel side kfunc is named bpf_obj_new_impl, as passing hidden arguments
to kfuncs still requires having them in prototype, unlike BPF helpers
which always take 5 arguments and have them checked using bpf_func_proto
in verifier, ignoring unset argument types.
Introduce __ign suffix to ignore a specific kfunc argument during type
checks, then use this to introduce support for passing type metadata to
the bpf_obj_new_impl kfunc.
The user passes BTF ID of the type it wants to allocates in program BTF,
the verifier then rewrites the first argument as the size of this type,
after performing some sanity checks (to ensure it exists and it is a
struct type).
The second argument is also fixed up and passed by the verifier. This is
the btf_struct_meta for the type being allocated. It would be needed
mostly for the offset array which is required for zero initializing
special fields while leaving the rest of storage in unitialized state.
It would also be needed in the next patch to perform proper destruction
of the object's special fields.
Under the hood, bpf_obj_new will call bpf_mem_alloc and bpf_mem_free,
using the any context BPF memory allocator introduced recently. To this
end, a global instance of the BPF memory allocator is initialized on
boot to be used for this purpose. This 'bpf_global_ma' serves all
allocations for bpf_obj_new. In the future, bpf_obj_new variants will
allow specifying a custom allocator.
Note that now that bpf_obj_new can be used to allocate objects that can
be linked to BPF linked list (when future linked list helpers are
available), we need to also free the elements using bpf_mem_free.
However, since the draining of elements is done outside the
bpf_spin_lock, we need to do migrate_disable around the call since
bpf_list_head_free can be called from map free path where migration is
enabled. Otherwise, when called from BPF programs migration is already
disabled.
A convenience macro is included in the bpf_experimental.h header to hide
over the ugly details of the implementation, leading to user code
looking similar to a language level extension which allocates and
constructs fields of a user type.
struct bar {
struct bpf_list_node node;
};
struct foo {
struct bpf_spin_lock lock;
struct bpf_list_head head __contains(bar, node);
};
void prog(void) {
struct foo *f;
f = bpf_obj_new(typeof(*f));
if (!f)
return;
...
}
A key piece of this story is still missing, i.e. the free function,
which will come in the next patch.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20221118015614.2013203-14-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
Jason A. Donenfeld
|
8032bf1233 |
treewide: use get_random_u32_below() instead of deprecated function
This is a simple mechanical transformation done by: @@ expression E; @@ - prandom_u32_max + get_random_u32_below (E) Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Reviewed-by: SeongJae Park <sj@kernel.org> # for damon Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> # for arm Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> |
|
Jakub Kicinski
|
94adb5e29e |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Jakub Kicinski
|
3566a79c9e |
bpf-next-for-netdev
-----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTFp0I1jqZrAX+hPRXbK58LschIgwUCY08JQQAKCRDbK58LschI g0M0AQCWGrJcnQFut1qwR9efZUadwxtKGAgpaA/8Smd8+v7c8AD/SeHQuGfkFiD6 rx18hv1mTfG0HuPnFQy6YZQ98vmznwE= =DaeS -----END PGP SIGNATURE----- Merge tag 'for-netdev' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Daniel Borkmann says: ==================== pull-request: bpf-next 2022-10-18 We've added 33 non-merge commits during the last 14 day(s) which contain a total of 31 files changed, 874 insertions(+), 538 deletions(-). The main changes are: 1) Add RCU grace period chaining to BPF to wait for the completion of access from both sleepable and non-sleepable BPF programs, from Hou Tao & Paul E. McKenney. 2) Improve helper UAPI by explicitly defining BPF_FUNC_xxx integer values. In the wild we have seen OS vendors doing buggy backports where helper call numbers mismatched. This is an attempt to make backports more foolproof, from Andrii Nakryiko. 3) Add libbpf *_opts API-variants for bpf_*_get_fd_by_id() functions, from Roberto Sassu. 4) Fix libbpf's BTF dumper for structs with padding-only fields, from Eduard Zingerman. 5) Fix various libbpf bugs which have been found from fuzzing with malformed BPF object files, from Shung-Hsi Yu. 6) Clean up an unneeded check on existence of SSE2 in BPF x86-64 JIT, from Jie Meng. 7) Fix various ASAN bugs in both libbpf and selftests when running the BPF selftest suite on arm64, from Xu Kuohai. 8) Fix missing bpf_iter_vma_offset__destroy() call in BPF iter selftest and use in-skeleton link pointer to remove an explicit bpf_link__destroy(), from Jiri Olsa. 9) Fix BPF CI breakage by pointing to iptables-legacy instead of relying on symlinked iptables which got upgraded to iptables-nft, from Martin KaFai Lau. 10) Minor BPF selftest improvements all over the place, from various others. * tag 'for-netdev' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (33 commits) bpf/docs: Update README for most recent vmtest.sh bpf: Use rcu_trace_implies_rcu_gp() for program array freeing bpf: Use rcu_trace_implies_rcu_gp() in local storage map bpf: Use rcu_trace_implies_rcu_gp() in bpf memory allocator rcu-tasks: Provide rcu_trace_implies_rcu_gp() selftests/bpf: Use sys_pidfd_open() helper when possible libbpf: Fix null-pointer dereference in find_prog_by_sec_insn() libbpf: Deal with section with no data gracefully libbpf: Use elf_getshdrnum() instead of e_shnum selftest/bpf: Fix error usage of ASSERT_OK in xdp_adjust_tail.c selftests/bpf: Fix error failure of case test_xdp_adjust_tail_grow selftest/bpf: Fix memory leak in kprobe_multi_test selftests/bpf: Fix memory leak caused by not destroying skeleton libbpf: Fix memory leak in parse_usdt_arg() libbpf: Fix use-after-free in btf_dump_name_dups selftests/bpf: S/iptables/iptables-legacy/ in the bpf_nf and xdp_synproxy test selftests/bpf: Alphabetize DENYLISTs selftests/bpf: Add tests for _opts variants of bpf_*_get_fd_by_id() libbpf: Introduce bpf_link_get_fd_by_id_opts() libbpf: Introduce bpf_btf_get_fd_by_id_opts() ... ==================== Link: https://lore.kernel.org/r/20221018210631.11211-1-daniel@iogearbox.net Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
Hou Tao
|
4835f9ee98 |
bpf: Use rcu_trace_implies_rcu_gp() for program array freeing
To support both sleepable and normal uprobe bpf program, the freeing of trace program array chains a RCU-tasks-trace grace period and a normal RCU grace period one after the other. With the introduction of rcu_trace_implies_rcu_gp(), __bpf_prog_array_free_sleepable_cb() can check whether or not a normal RCU grace period has also passed after a RCU-tasks-trace grace period has passed. If it is true, it is safe to invoke kfree() directly. Signed-off-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20221014113946.965131-5-houtao@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jason A. Donenfeld
|
a251c17aa5 |
treewide: use get_random_u32() when possible
The prandom_u32() function has been a deprecated inline wrapper around get_random_u32() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. The same also applies to get_random_int(), which is just a wrapper around get_random_u32(). This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Acked-by: Helge Deller <deller@gmx.de> # for parisc Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> |
|
|
Jason A. Donenfeld
|
81895a65ec |
treewide: use prandom_u32_max() when possible, part 1
Rather than incurring a division or requesting too many random bytes for
the given range, use the prandom_u32_max() function, which only takes
the minimum required bytes from the RNG and avoids divisions. This was
done mechanically with this coccinelle script:
@basic@
expression E;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
typedef u64;
@@
(
- ((T)get_random_u32() % (E))
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ((E) - 1))
+ prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2)
|
- ((u64)(E) * get_random_u32() >> 32)
+ prandom_u32_max(E)
|
- ((T)get_random_u32() & ~PAGE_MASK)
+ prandom_u32_max(PAGE_SIZE)
)
@multi_line@
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
identifier RAND;
expression E;
@@
- RAND = get_random_u32();
... when != RAND
- RAND %= (E);
+ RAND = prandom_u32_max(E);
// Find a potential literal
@literal_mask@
expression LITERAL;
type T;
identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32";
position p;
@@
((T)get_random_u32()@p & (LITERAL))
// Add one to the literal.
@script:python add_one@
literal << literal_mask.LITERAL;
RESULT;
@@
value = None
if literal.startswith('0x'):
value = int(literal, 16)
elif literal[0] in '123456789':
value = int(literal, 10)
if value is None:
print("I don't know how to handle %s" % (literal))
cocci.include_match(False)
elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1:
print("Skipping 0x%x for cleanup elsewhere" % (value))
cocci.include_match(False)
elif value & (value + 1) != 0:
print("Skipping 0x%x because it's not a power of two minus one" % (value))
cocci.include_match(False)
elif literal.startswith('0x'):
coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1))
else:
coccinelle.RESULT = cocci.make_expr("%d" % (value + 1))
// Replace the literal mask with the calculated result.
@plus_one@
expression literal_mask.LITERAL;
position literal_mask.p;
expression add_one.RESULT;
identifier FUNC;
@@
- (FUNC()@p & (LITERAL))
+ prandom_u32_max(RESULT)
@collapse_ret@
type T;
identifier VAR;
expression E;
@@
{
- T VAR;
- VAR = (E);
- return VAR;
+ return E;
}
@drop_var@
type T;
identifier VAR;
@@
{
- T VAR;
... when != VAR
}
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: KP Singh <kpsingh@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap
Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
|
|
|
Linus Torvalds
|
27bc50fc90 |
- Yu Zhao's Multi-Gen LRU patches are here. They've been under test in
linux-next for a couple of months without, to my knowledge, any negative reports (or any positive ones, come to that). - Also the Maple Tree from Liam R. Howlett. An overlapping range-based tree for vmas. It it apparently slight more efficient in its own right, but is mainly targeted at enabling work to reduce mmap_lock contention. Liam has identified a number of other tree users in the kernel which could be beneficially onverted to mapletrees. Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat (https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com). This has yet to be addressed due to Liam's unfortunately timed vacation. He is now back and we'll get this fixed up. - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses clang-generated instrumentation to detect used-unintialized bugs down to the single bit level. KMSAN keeps finding bugs. New ones, as well as the legacy ones. - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of memory into THPs. - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support file/shmem-backed pages. - userfaultfd updates from Axel Rasmussen - zsmalloc cleanups from Alexey Romanov - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure - Huang Ying adds enhancements to NUMA balancing memory tiering mode's page promotion, with a new way of detecting hot pages. - memcg updates from Shakeel Butt: charging optimizations and reduced memory consumption. - memcg cleanups from Kairui Song. - memcg fixes and cleanups from Johannes Weiner. - Vishal Moola provides more folio conversions - Zhang Yi removed ll_rw_block() :( - migration enhancements from Peter Xu - migration error-path bugfixes from Huang Ying - Aneesh Kumar added ability for a device driver to alter the memory tiering promotion paths. For optimizations by PMEM drivers, DRM drivers, etc. - vma merging improvements from Jakub Matěn. - NUMA hinting cleanups from David Hildenbrand. - xu xin added aditional userspace visibility into KSM merging activity. - THP & KSM code consolidation from Qi Zheng. - more folio work from Matthew Wilcox. - KASAN updates from Andrey Konovalov. - DAMON cleanups from Kaixu Xia. - DAMON work from SeongJae Park: fixes, cleanups. - hugetlb sysfs cleanups from Muchun Song. - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core. -----BEGIN PGP SIGNATURE----- iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCY0HaPgAKCRDdBJ7gKXxA joPjAQDZ5LlRCMWZ1oxLP2NOTp6nm63q9PWcGnmY50FjD/dNlwEAnx7OejCLWGWf bbTuk6U2+TKgJa4X7+pbbejeoqnt5QU= =xfWx -----END PGP SIGNATURE----- Merge tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in linux-next for a couple of months without, to my knowledge, any negative reports (or any positive ones, come to that). - Also the Maple Tree from Liam Howlett. An overlapping range-based tree for vmas. It it apparently slightly more efficient in its own right, but is mainly targeted at enabling work to reduce mmap_lock contention. Liam has identified a number of other tree users in the kernel which could be beneficially onverted to mapletrees. Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat at [1]. This has yet to be addressed due to Liam's unfortunately timed vacation. He is now back and we'll get this fixed up. - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses clang-generated instrumentation to detect used-unintialized bugs down to the single bit level. KMSAN keeps finding bugs. New ones, as well as the legacy ones. - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of memory into THPs. - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support file/shmem-backed pages. - userfaultfd updates from Axel Rasmussen - zsmalloc cleanups from Alexey Romanov - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure - Huang Ying adds enhancements to NUMA balancing memory tiering mode's page promotion, with a new way of detecting hot pages. - memcg updates from Shakeel Butt: charging optimizations and reduced memory consumption. - memcg cleanups from Kairui Song. - memcg fixes and cleanups from Johannes Weiner. - Vishal Moola provides more folio conversions - Zhang Yi removed ll_rw_block() :( - migration enhancements from Peter Xu - migration error-path bugfixes from Huang Ying - Aneesh Kumar added ability for a device driver to alter the memory tiering promotion paths. For optimizations by PMEM drivers, DRM drivers, etc. - vma merging improvements from Jakub Matěn. - NUMA hinting cleanups from David Hildenbrand. - xu xin added aditional userspace visibility into KSM merging activity. - THP & KSM code consolidation from Qi Zheng. - more folio work from Matthew Wilcox. - KASAN updates from Andrey Konovalov. - DAMON cleanups from Kaixu Xia. - DAMON work from SeongJae Park: fixes, cleanups. - hugetlb sysfs cleanups from Muchun Song. - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core. Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1] * tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits) hugetlb: allocate vma lock for all sharable vmas hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer hugetlb: fix vma lock handling during split vma and range unmapping mglru: mm/vmscan.c: fix imprecise comments mm/mglru: don't sync disk for each aging cycle mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol mm: memcontrol: use do_memsw_account() in a few more places mm: memcontrol: deprecate swapaccounting=0 mode mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled mm/secretmem: remove reduntant return value mm/hugetlb: add available_huge_pages() func mm: remove unused inline functions from include/linux/mm_inline.h selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd selftests/vm: add thp collapse shmem testing selftests/vm: add thp collapse file and tmpfs testing selftests/vm: modularize thp collapse memory operations selftests/vm: dedup THP helpers mm/khugepaged: add tracepoint to hpage_collapse_scan_file() mm/madvise: add file and shmem support to MADV_COLLAPSE ... |
|
Alexander Potapenko
|
a6a7aaba7f |
bpf: kmsan: initialize BPF registers with zeroes
When executing BPF programs, certain registers may get passed uninitialized to helper functions. E.g. when performing a JMP_CALL, registers BPF_R1-BPF_R5 are always passed to the helper, no matter how many of them are actually used. Passing uninitialized values as function parameters is technically undefined behavior, so we work around it by always initializing the registers. Link: https://lkml.kernel.org/r/20220915150417.722975-42-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Marco Elver <elver@google.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
|
Song Liu
|
19c02415da |
bpf: use bpf_prog_pack for bpf_dispatcher
Allocate bpf_dispatcher with bpf_prog_pack_alloc so that bpf_dispatcher can share pages with bpf programs. arch_prepare_bpf_dispatcher() is updated to provide a RW buffer as working area for arch code to write to. This also fixes CPA W^X warnning like: CPA refuse W^X violation: 8000000000000163 -> 0000000000000163 range: ... Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20220926184739.3512547-2-song@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jakub Kicinski
|
60ad1100d5 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/testing/selftests/net/.gitignore sort the net-next version and use it Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
Kuniyuki Iwashima
|
0947ae1121 |
bpf: Fix a data-race around bpf_jit_limit.
While reading bpf_jit_limit, it can be changed concurrently via sysctl,
WRITE_ONCE() in __do_proc_doulongvec_minmax(). The size of bpf_jit_limit
is long, so we need to add a paired READ_ONCE() to avoid load-tearing.
Fixes:
|
|
Jesper Dangaard Brouer
|
c8996c98f7 |
bpf: Add BPF-helper for accessing CLOCK_TAI
Commit
|
|
|
Jakub Kicinski
|
b3fce974d4 |
Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:
====================
bpf-next 2022-07-22
We've added 73 non-merge commits during the last 12 day(s) which contain
a total of 88 files changed, 3458 insertions(+), 860 deletions(-).
The main changes are:
1) Implement BPF trampoline for arm64 JIT, from Xu Kuohai.
2) Add ksyscall/kretsyscall section support to libbpf to simplify tracing kernel
syscalls through kprobe mechanism, from Andrii Nakryiko.
3) Allow for livepatch (KLP) and BPF trampolines to attach to the same kernel
function, from Song Liu & Jiri Olsa.
4) Add new kfunc infrastructure for netfilter's CT e.g. to insert and change
entries, from Kumar Kartikeya Dwivedi & Lorenzo Bianconi.
5) Add a ksym BPF iterator to allow for more flexible and efficient interactions
with kernel symbols, from Alan Maguire.
6) Bug fixes in libbpf e.g. for uprobe binary path resolution, from Dan Carpenter.
7) Fix BPF subprog function names in stack traces, from Alexei Starovoitov.
8) libbpf support for writing custom perf event readers, from Jon Doron.
9) Switch to use SPDX tag for BPF helper man page, from Alejandro Colomar.
10) Fix xsk send-only sockets when in busy poll mode, from Maciej Fijalkowski.
11) Reparent BPF maps and their charging on memcg offlining, from Roman Gushchin.
12) Multiple follow-up fixes around BPF lsm cgroup infra, from Stanislav Fomichev.
13) Use bootstrap version of bpftool where possible to speed up builds, from Pu Lehui.
14) Cleanup BPF verifier's check_func_arg() handling, from Joanne Koong.
15) Make non-prealloced BPF map allocations low priority to play better with
memcg limits, from Yafang Shao.
16) Fix BPF test runner to reject zero-length data for skbs, from Zhengchao Shao.
17) Various smaller cleanups and improvements all over the place.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (73 commits)
bpf: Simplify bpf_prog_pack_[size|mask]
bpf: Support bpf_trampoline on functions with IPMODIFY (e.g. livepatch)
bpf, x64: Allow to use caller address from stack
ftrace: Allow IPMODIFY and DIRECT ops on the same function
ftrace: Add modify_ftrace_direct_multi_nolock
bpf/selftests: Fix couldn't retrieve pinned program in xdp veth test
bpf: Fix build error in case of !CONFIG_DEBUG_INFO_BTF
selftests/bpf: Fix test_verifier failed test in unprivileged mode
selftests/bpf: Add negative tests for new nf_conntrack kfuncs
selftests/bpf: Add tests for new nf_conntrack kfuncs
selftests/bpf: Add verifier tests for trusted kfunc args
net: netfilter: Add kfuncs to set and change CT status
net: netfilter: Add kfuncs to set and change CT timeout
net: netfilter: Add kfuncs to allocate and insert CT
net: netfilter: Deduplicate code in bpf_{xdp,skb}_ct_lookup
bpf: Add documentation for kfuncs
bpf: Add support for forcing kfunc args to be trusted
bpf: Switch to new kfunc flags infrastructure
tools/resolve_btfids: Add support for 8-byte BTF sets
bpf: Introduce 8-byte BTF set
...
====================
Link: https://lore.kernel.org/r/20220722221218.29943-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
|
Song Liu
|
ea2babac63 |
bpf: Simplify bpf_prog_pack_[size|mask]
Simplify the logic that selects bpf_prog_pack_size, and always use (PMD_SIZE * num_possible_nodes()). This is a good tradeoff, as most of the performance benefit observed is from less direct map fragmentation [0]. Also, module_alloc(4MB) may not allocate 4MB aligned memory. Therefore, we cannot use (ptr & bpf_prog_pack_mask) to find the correct address of bpf_prog_pack. Fix this by checking the header address falls in the range of pack->ptr and (pack->ptr + bpf_prog_pack_size). [0] https://lore.kernel.org/bpf/20220707223546.4124919-1-song@kernel.org/ Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/20220713204950.3015201-1-song@kernel.org |
|
|
Jakub Kicinski
|
816cd16883 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/net/sock.h |
|
|
Song Liu
|
1d5f82d9dd |
bpf, x86: fix freeing of not-finalized bpf_prog_pack
syzbot reported a few issues with bpf_prog_pack [1], [2]. This only happens
with multiple subprogs. In jit_subprogs(), we first call bpf_int_jit_compile()
on each sub program. And then, we call it on each sub program again. jit_data
is not freed in the first call of bpf_int_jit_compile(). Similarly we don't
call bpf_jit_binary_pack_finalize() in the first call of bpf_int_jit_compile().
If bpf_int_jit_compile() failed for one sub program, we will call
bpf_jit_binary_pack_finalize() for this sub program. However, we don't have a
chance to call it for other sub programs. Then we will hit "goto out_free" in
jit_subprogs(), and call bpf_jit_free on some subprograms that haven't got
bpf_jit_binary_pack_finalize() yet.
At this point, bpf_jit_binary_pack_free() is called and the whole 2MB page is
freed erroneously.
Fix this with a custom bpf_jit_free() for x86_64, which calls
bpf_jit_binary_pack_finalize() if necessary. Also, with custom
bpf_jit_free(), bpf_prog_aux->use_bpf_prog_pack is not needed any more,
remove it.
Fixes:
|
|
Eric Dumazet
|
0326195f52 |
bpf: Make sure mac_header was set before using it
Classic BPF has a way to load bytes starting from the mac header.
Some skbs do not have a mac header, and skb_mac_header()
in this case is returning a pointer that 65535 bytes after
skb->head.
Existing range check in bpf_internal_load_pointer_neg_helper()
was properly kicking and no illegal access was happening.
New sanity check in skb_mac_header() is firing, so we need
to avoid it.
WARNING: CPU: 1 PID: 28990 at include/linux/skbuff.h:2785 skb_mac_header include/linux/skbuff.h:2785 [inline]
WARNING: CPU: 1 PID: 28990 at include/linux/skbuff.h:2785 bpf_internal_load_pointer_neg_helper+0x1b1/0x1c0 kernel/bpf/core.c:74
Modules linked in:
CPU: 1 PID: 28990 Comm: syz-executor.0 Not tainted 5.19.0-rc4-syzkaller-00865-g4874fb9484be #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
RIP: 0010:skb_mac_header include/linux/skbuff.h:2785 [inline]
RIP: 0010:bpf_internal_load_pointer_neg_helper+0x1b1/0x1c0 kernel/bpf/core.c:74
Code: ff ff 45 31 f6 e9 5a ff ff ff e8 aa 27 40 00 e9 3b ff ff ff e8 90 27 40 00 e9 df fe ff ff e8 86 27 40 00 eb 9e e8 2f 2c f3 ff <0f> 0b eb b1 e8 96 27 40 00 e9 79 fe ff ff 90 41 57 41 56 41 55 41
RSP: 0018:ffffc9000309f668 EFLAGS: 00010216
RAX: 0000000000000118 RBX: ffffffffffeff00c RCX: ffffc9000e417000
RDX: 0000000000040000 RSI: ffffffff81873f21 RDI: 0000000000000003
RBP: ffff8880842878c0 R08: 0000000000000003 R09: 000000000000ffff
R10: 000000000000ffff R11: 0000000000000001 R12: 0000000000000004
R13: ffff88803ac56c00 R14: 000000000000ffff R15: dffffc0000000000
FS: 00007f5c88a16700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fdaa9f6c058 CR3: 000000003a82c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
____bpf_skb_load_helper_32 net/core/filter.c:276 [inline]
bpf_skb_load_helper_32+0x191/0x220 net/core/filter.c:264
Fixes:
|
|
Stanislav Fomichev
|
c0e19f2c9a |
bpf: minimize number of allocated lsm slots per program
Previous patch adds 1:1 mapping between all 211 LSM hooks
and bpf_cgroup program array. Instead of reserving a slot per
possible hook, reserve 10 slots per cgroup for lsm programs.
Those slots are dynamically allocated on demand and reclaimed.
struct cgroup_bpf {
struct bpf_prog_array * effective[33]; /* 0 264 */
/* --- cacheline 4 boundary (256 bytes) was 8 bytes ago --- */
struct hlist_head progs[33]; /* 264 264 */
/* --- cacheline 8 boundary (512 bytes) was 16 bytes ago --- */
u8 flags[33]; /* 528 33 */
/* XXX 7 bytes hole, try to pack */
struct list_head storages; /* 568 16 */
/* --- cacheline 9 boundary (576 bytes) was 8 bytes ago --- */
struct bpf_prog_array * inactive; /* 584 8 */
struct percpu_ref refcnt; /* 592 16 */
struct work_struct release_work; /* 608 72 */
/* size: 680, cachelines: 11, members: 7 */
/* sum members: 673, holes: 1, sum holes: 7 */
/* last cacheline: 40 bytes */
};
Reviewed-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/r/20220628174314.1216643-5-sdf@google.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Stanislav Fomichev
|
69fd337a97 |
bpf: per-cgroup lsm flavor
Allow attaching to lsm hooks in the cgroup context. Attaching to per-cgroup LSM works exactly like attaching to other per-cgroup hooks. New BPF_LSM_CGROUP is added to trigger new mode; the actual lsm hook we attach to is signaled via existing attach_btf_id. For the hooks that have 'struct socket' or 'struct sock' as its first argument, we use the cgroup associated with that socket. For the rest, we use 'current' cgroup (this is all on default hierarchy == v2 only). Note that for some hooks that work on 'struct sock' we still take the cgroup from 'current' because some of them work on the socket that hasn't been properly initialized yet. Behind the scenes, we allocate a shim program that is attached to the trampoline and runs cgroup effective BPF programs array. This shim has some rudimentary ref counting and can be shared between several programs attaching to the same lsm hook from different cgroups. Note that this patch bloats cgroup size because we add 211 cgroup_bpf_attach_type(s) for simplicity sake. This will be addressed in the subsequent patch. Also note that we only add non-sleepable flavor for now. To enable sleepable use-cases, bpf_prog_run_array_cg has to grab trace rcu, shim programs have to be freed via trace rcu, cgroup_bpf.effective should be also trace-rcu-managed + maybe some other changes that I'm not aware of. Reviewed-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/r/20220628174314.1216643-4-sdf@google.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Tony Ambardar
|
95acd8817e |
bpf, x64: Add predicate for bpf2bpf with tailcalls support in JIT
The BPF core/verifier is hard-coded to permit mixing bpf2bpf and tail calls for only x86-64. Change the logic to instead rely on a new weak function 'bool bpf_jit_supports_subprog_tailcalls(void)', which a capable JIT backend can override. Update the x86-64 eBPF JIT to reflect this. Signed-off-by: Tony Ambardar <Tony.Ambardar@gmail.com> [jakub: drop MIPS bits and tweak patch subject] Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20220617105735.733938-2-jakub@cloudflare.com |
|
Delyan Kratunov
|
8c7dcb84e3 |
bpf: implement sleepable uprobes by chaining gps
uprobes work by raising a trap, setting a task flag from within the interrupt handler, and processing the actual work for the uprobe on the way back to userspace. As a result, uprobe handlers already execute in a might_fault/_sleep context. The primary obstacle to sleepable bpf uprobe programs is therefore on the bpf side. Namely, the bpf_prog_array attached to the uprobe is protected by normal rcu. In order for uprobe bpf programs to become sleepable, it has to be protected by the tasks_trace rcu flavor instead (and kfree() called after a corresponding grace period). Therefore, the free path for bpf_prog_array now chains a tasks_trace and normal grace periods one after the other. Users who iterate under tasks_trace read section would be safe, as would users who iterate under normal read sections (from non-sleepable locations). The downside is that the tasks_trace latency affects all perf_event-attached bpf programs (and not just uprobe ones). This is deemed safe given the possible attach rates for kprobe/uprobe/tp programs. Separately, non-sleepable programs need access to dynamically sized rcu-protected maps, so bpf_run_prog_array_sleepables now conditionally takes an rcu read section, in addition to the overarching tasks_trace section. Signed-off-by: Delyan Kratunov <delyank@fb.com> Link: https://lore.kernel.org/r/ce844d62a2fd0443b08c5ab02e95bc7149f9aeb1.1655248076.git.delyank@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Pu Lehui
|
cc1685546d |
bpf: Correct the comment about insn_to_jit_off
The insn_to_jit_off passed to bpf_prog_fill_jited_linfo should be the first byte of the next instruction, or the byte off to the end of the current instruction. Signed-off-by: Pu Lehui <pulehui@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20220530092815.1112406-4-pulehui@huawei.com |
|
Menglong Dong
|
caff1fa411 |
bpf: Fix probe read error in ___bpf_prog_run()
I think there is something wrong with BPF_PROBE_MEM in ___bpf_prog_run()
in big-endian machine. Let's make a test and see what will happen if we
want to load a 'u16' with BPF_PROBE_MEM.
Let's make the src value '0x0001', the value of dest register will become
0x0001000000000000, as the value will be loaded to the first 2 byte of
DST with following code:
bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) (SRC + insn->off));
Obviously, the value in DST is not correct. In fact, we can compare
BPF_PROBE_MEM with LDX_MEM_H:
DST = *(SIZE *)(unsigned long) (SRC + insn->off);
If the memory load is done by LDX_MEM_H, the value in DST will be 0x1 now.
And I think this error results in the test case 'test_bpf_sk_storage_map'
failing:
test_bpf_sk_storage_map:PASS:bpf_iter_bpf_sk_storage_map__open_and_load 0 nsec
test_bpf_sk_storage_map:PASS:socket 0 nsec
test_bpf_sk_storage_map:PASS:map_update 0 nsec
test_bpf_sk_storage_map:PASS:socket 0 nsec
test_bpf_sk_storage_map:PASS:map_update 0 nsec
test_bpf_sk_storage_map:PASS:socket 0 nsec
test_bpf_sk_storage_map:PASS:map_update 0 nsec
test_bpf_sk_storage_map:PASS:attach_iter 0 nsec
test_bpf_sk_storage_map:PASS:create_iter 0 nsec
test_bpf_sk_storage_map:PASS:read 0 nsec
test_bpf_sk_storage_map:FAIL:ipv6_sk_count got 0 expected 3
$10/26 bpf_iter/bpf_sk_storage_map:FAIL
The code of the test case is simply, it will load sk->sk_family to the
register with BPF_PROBE_MEM and check if it is AF_INET6. With this patch,
now the test case 'bpf_iter' can pass:
$10 bpf_iter:OK
Fixes:
|
|
|
Song Liu
|
fe736565ef |
bpf: Introduce bpf_arch_text_invalidate for bpf_prog_pack
Introduce bpf_arch_text_invalidate and use it to fill unused part of the bpf_prog_pack with illegal instructions when a BPF program is freed. Fixes: |
|
|
Song Liu
|
d88bb5eed0 |
bpf: Fill new bpf_prog_pack with illegal instructions
bpf_prog_pack enables sharing huge pages among multiple BPF programs. These pages are marked as executable before the JIT engine fill it with BPF programs. To make these pages safe, fill the hole bpf_prog_pack with illegal instructions before making it executable. Fixes: |
|
Alexei Starovoitov
|
4b6313cf99 |
bpf: Fix combination of jit blinding and pointers to bpf subprogs.
The combination of jit blinding and pointers to bpf subprogs causes:
[ 36.989548] BUG: unable to handle page fault for address: 0000000100000001
[ 36.990342] #PF: supervisor instruction fetch in kernel mode
[ 36.990968] #PF: error_code(0x0010) - not-present page
[ 36.994859] RIP: 0010:0x100000001
[ 36.995209] Code: Unable to access opcode bytes at RIP 0xffffffd7.
[ 37.004091] Call Trace:
[ 37.004351] <TASK>
[ 37.004576] ? bpf_loop+0x4d/0x70
[ 37.004932] ? bpf_prog_3899083f75e4c5de_F+0xe3/0x13b
The jit blinding logic didn't recognize that ld_imm64 with an address
of bpf subprogram is a special instruction and proceeded to randomize it.
By itself it wouldn't have been an issue, but jit_subprogs() logic
relies on two step process to JIT all subprogs and then JIT them
again when addresses of all subprogs are known.
Blinding process in the first JIT phase caused second JIT to miss
adjustment of special ld_imm64.
Fix this issue by ignoring special ld_imm64 instructions that don't have
user controlled constants and shouldn't be blinded.
Fixes:
|
|
Feng Zhou
|
07343110b2 |
bpf: add bpf_map_lookup_percpu_elem for percpu map
Add new ebpf helpers bpf_map_lookup_percpu_elem. The implementation method is relatively simple, refer to the implementation method of map_lookup_elem of percpu map, increase the parameters of cpu, and obtain it according to the specified cpu. Signed-off-by: Feng Zhou <zhoufeng.zf@bytedance.com> Link: https://lore.kernel.org/r/20220511093854.411-2-zhoufeng.zf@bytedance.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Song Liu
|
e581094167 |
bpf: Fix bpf_prog_pack when PMU_SIZE is not defined
PMD_SIZE is not available in some special config, e.g. ARCH=arm with
CONFIG_MMU=n. Use bpf_prog_pack of PAGE_SIZE in these cases.
Fixes:
|
|
|
Song Liu
|
96805674e5 |
bpf: Fix bpf_prog_pack for multi-node setup
module_alloc requires num_online_nodes * PMD_SIZE to allocate huge pages.
bpf_prog_pack uses pack of size num_online_nodes * PMD_SIZE.
OTOH, module_alloc returns addresses that are PMD_SIZE aligned (instead of
num_online_nodes * PMD_SIZE aligned). Therefore, PMD_MASK should be used
to calculate pack_ptr in bpf_prog_pack_free().
Fixes:
|
|
|
Song Liu
|
ef078600ee |
bpf: Select proper size for bpf_prog_pack
Using HPAGE_PMD_SIZE as the size for bpf_prog_pack is not ideal in some
cases. Specifically, for NUMA systems, __vmalloc_node_range requires
PMD_SIZE * num_online_nodes() to allocate huge pages. Also, if the system
does not support huge pages (i.e., with cmdline option nohugevmalloc), it
is better to use PAGE_SIZE packs.
Add logic to select proper size for bpf_prog_pack. This solution is not
ideal, as it makes assumption about the behavior of module_alloc and
__vmalloc_node_range. However, it appears to be the easiest solution as
it doesn't require changes in module_alloc and vmalloc code.
Fixes:
|
|
|
Hou Tao
|
d2a3b7c5be |
bpf: Fix net.core.bpf_jit_harden race
It is the bpf_jit_harden counterpart to commit
|
|
|
Song Liu
|
676b2daaba |
bpf, x86: Set header->size properly before freeing it
On do_jit failure path, the header is freed by bpf_jit_binary_pack_free. While bpf_jit_binary_pack_free doesn't require proper ro_header->size, bpf_prog_pack_free still uses it. Set header->size in bpf_int_jit_compile before calling bpf_jit_binary_pack_free. Fixes: |
|
|
Song Liu
|
d24d2a2b0a |
bpf: bpf_prog_pack: Set proper size before freeing ro_header
bpf_prog_pack_free() uses header->size to decide whether the header
should be freed with module_memfree() or the bpf_prog_pack logic.
However, in kvmalloc() failure path of bpf_jit_binary_pack_alloc(),
header->size is not set yet. As a result, bpf_prog_pack_free() may treat
a slice of a pack as a standalone kvmalloc'd header and call
module_memfree() on the whole pack. This in turn causes use-after-free by
other users of the pack.
Fix this by setting ro_header->size before freeing ro_header.
Fixes:
|
|
|
Song Liu
|
4cc0991abd |
bpf: Fix bpf_prog_pack build for ppc64_defconfig
bpf_prog_pack causes build error with powerpc ppc64_defconfig:
kernel/bpf/core.c:830:23: error: variably modified 'bitmap' at file scope
830 | unsigned long bitmap[BITS_TO_LONGS(BPF_PROG_CHUNK_COUNT)];
| ^~~~~~
This is because the marco expands as:
unsigned long bitmap[((((((1UL) << (16 + __pte_index_size)) / (1 << 6))) \
+ ((sizeof(long) * 8)) - 1) / ((sizeof(long) * 8)))];
where __pte_index_size is a global variable.
Fix it by turning bitmap into a 0-length array.
Fixes:
|
|
|
Song Liu
|
c1b13a9451 |
bpf: Fix bpf_prog_pack build HPAGE_PMD_SIZE
Fix build with CONFIG_TRANSPARENT_HUGEPAGE=n with BPF_PROG_PACK_SIZE as
PAGE_SIZE.
Fixes:
|
|
Song Liu
|
33c9805860 |
bpf: Introduce bpf_jit_binary_pack_[alloc|finalize|free]
This is the jit binary allocator built on top of bpf_prog_pack. bpf_prog_pack allocates RO memory, which cannot be used directly by the JIT engine. Therefore, a temporary rw buffer is allocated for the JIT engine. Once JIT is done, bpf_jit_binary_pack_finalize is used to copy the program to the RO memory. bpf_jit_binary_pack_alloc reserves 16 bytes of extra space for illegal instructions, which is small than the 128 bytes space reserved by bpf_jit_binary_alloc. This change is necessary for bpf_jit_binary_hdr to find the correct header. Also, flag use_bpf_prog_pack is added to differentiate a program allocated by bpf_jit_binary_pack_alloc. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20220204185742.271030-9-song@kernel.org |
|
|
Song Liu
|
57631054fa |
bpf: Introduce bpf_prog_pack allocator
Most BPF programs are small, but they consume a page each. For systems with busy traffic and many BPF programs, this could add significant pressure to instruction TLB. High iTLB pressure usually causes slow down for the whole system, which includes visible performance degradation for production workloads. Introduce bpf_prog_pack allocator to pack multiple BPF programs in a huge page. The memory is then allocated in 64 byte chunks. Memory allocated by bpf_prog_pack allocator is RO protected after initial allocation. To write to it, the user (jit engine) need to use text poke API. Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20220204185742.271030-8-song@kernel.org |
|
|
Song Liu
|
ebc1415d9b |
bpf: Introduce bpf_arch_text_copy
This will be used to copy JITed text to RO protected module memory. On x86, bpf_arch_text_copy is implemented with text_poke_copy. bpf_arch_text_copy returns pointer to dst on success, and ERR_PTR(errno) on errors. Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20220204185742.271030-7-song@kernel.org |
|
|
Song Liu
|
d00c6473b1 |
bpf: Use prog->jited_len in bpf_prog_ksym_set_addr()
Using prog->jited_len is simpler and more accurate than current estimation (header + header->size). Also, fix missing prog->jited_len with multi function program. This hasn't been a real issue before this. Signed-off-by: Song Liu <song@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20220204185742.271030-5-song@kernel.org |
|
|
Song Liu
|
ed2d9e1a26 |
bpf: Use size instead of pages in bpf_binary_header
This is necessary to charge sub page memory for the BPF program. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20220204185742.271030-4-song@kernel.org |
|
|
Song Liu
|
3486bedd99 |
bpf: Use bytes instead of pages for bpf_jit_[charge|uncharge]_modmem
This enables sub-page memory charge and allocation. Signed-off-by: Song Liu <songliubraving@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20220204185742.271030-3-song@kernel.org |
|
Pavel Begunkov
|
46531a3036 |
cgroup/bpf: fast path skb BPF filtering
Even though there is a static key protecting from overhead from cgroup-bpf skb filtering when there is nothing attached, in many cases it's not enough as registering a filter for one type will ruin the fast path for all others. It's observed in production servers I've looked at but also in laptops, where registration is done during init by systemd or something else. Add a per-socket fast path check guarding from such overhead. This affects both receive and transmit paths of TCP, UDP and other protocols. It showed ~1% tx/s improvement in small payload UDP send benchmarks using a real NIC and in a server environment and the number jumps to 2-3% for preemtible kernels. Reviewed-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/r/d8c58857113185a764927a46f4b5a058d36d3ec3.1643292455.git.asml.silence@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Toke Hoiland-Jorgensen
|
f45d5b6ce2 |
bpf: generalise tail call map compatibility check
The check for tail call map compatibility ensures that tail calls only happen between maps of the same type. To ensure backwards compatibility for XDP frags we need a similar type of check for cpumap and devmap programs, so move the state from bpf_array_aux into bpf_map, add xdp_has_frags to the check, and apply the same check to cpumap and devmap. Acked-by: John Fastabend <john.fastabend@gmail.com> Co-developed-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> Signed-off-by: Toke Hoiland-Jorgensen <toke@redhat.com> Link: https://lore.kernel.org/r/f19fd97c0328a39927f3ad03e1ca6b43fd53cdfd.1642758637.git.lorenzo@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Christoph Hellwig
|
06edc59c1f |
bpf, docs: Prune all references to "internal BPF"
The eBPF name has completely taken over from eBPF in general usage for the actual eBPF representation, or BPF for any general in-kernel use. Prune all remaining references to "internal BPF". Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20211119163215.971383-4-hch@lst.de |
|
|
Christoph Hellwig
|
ccb00292eb |
bpf: Remove a redundant comment on bpf_prog_free
The comment telling that the prog_free helper is freeing the program is not exactly useful, so just remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20211119163215.971383-3-hch@lst.de |
|
Tiezhu Yang
|
ebf7f6f0a6 |
bpf: Change value of MAX_TAIL_CALL_CNT from 32 to 33
In the current code, the actual max tail call count is 33 which is greater than MAX_TAIL_CALL_CNT (defined as 32). The actual limit is not consistent with the meaning of MAX_TAIL_CALL_CNT and thus confusing at first glance. We can see the historical evolution from commit |
|
Martin KaFai Lau
|
3990ed4c42 |
bpf: Stop caching subprog index in the bpf_pseudo_func insn
This patch is to fix an out-of-bound access issue when jit-ing the
bpf_pseudo_func insn (i.e. ld_imm64 with src_reg == BPF_PSEUDO_FUNC)
In jit_subprog(), it currently reuses the subprog index cached in
insn[1].imm. This subprog index is an index into a few array related
to subprogs. For example, in jit_subprog(), it is an index to the newly
allocated 'struct bpf_prog **func' array.
The subprog index was cached in insn[1].imm after add_subprog(). However,
this could become outdated (and too big in this case) if some subprogs
are completely removed during dead code elimination (in
adjust_subprog_starts_after_remove). The cached index in insn[1].imm
is not updated accordingly and causing out-of-bound issue in the later
jit_subprog().
Unlike bpf_pseudo_'func' insn, the current bpf_pseudo_'call' insn
is handling the DCE properly by calling find_subprog(insn->imm) to
figure out the index instead of caching the subprog index.
The existing bpf_adj_branches() will adjust the insn->imm
whenever insn is added or removed.
Instead of having two ways handling subprog index,
this patch is to make bpf_pseudo_func works more like
bpf_pseudo_call.
First change is to stop caching the subprog index result
in insn[1].imm after add_subprog(). The verification
process will use find_subprog(insn->imm) to figure
out the subprog index.
Second change is in bpf_adj_branches() and have it to
adjust the insn->imm for the bpf_pseudo_func insn also
whenever insn is added or removed.
Third change is in jit_subprog(). Like the bpf_pseudo_call handling,
bpf_pseudo_func temporarily stores the find_subprog() result
in insn->off. It is fine because the prog's insn has been finalized
at this point. insn->off will be reset back to 0 later to avoid
confusing the userspace prog dump tool.
Fixes:
|
|
|
Jakub Kicinski
|
b7b98f8689 |
Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says: ==================== pull-request: bpf-next 2021-11-01 We've added 181 non-merge commits during the last 28 day(s) which contain a total of 280 files changed, 11791 insertions(+), 5879 deletions(-). The main changes are: 1) Fix bpf verifier propagation of 64-bit bounds, from Alexei. 2) Parallelize bpf test_progs, from Yucong and Andrii. 3) Deprecate various libbpf apis including af_xdp, from Andrii, Hengqi, Magnus. 4) Improve bpf selftests on s390, from Ilya. 5) bloomfilter bpf map type, from Joanne. 6) Big improvements to JIT tests especially on Mips, from Johan. 7) Support kernel module function calls from bpf, from Kumar. 8) Support typeless and weak ksym in light skeleton, from Kumar. 9) Disallow unprivileged bpf by default, from Pawan. 10) BTF_KIND_DECL_TAG support, from Yonghong. 11) Various bpftool cleanups, from Quentin. * https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (181 commits) libbpf: Deprecate AF_XDP support kbuild: Unify options for BTF generation for vmlinux and modules selftests/bpf: Add a testcase for 64-bit bounds propagation issue. bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit. bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off. selftests/bpf: Fix also no-alu32 strobemeta selftest bpf: Add missing map_delete_elem method to bloom filter map selftests/bpf: Add bloom map success test for userspace calls bpf: Add alignment padding for "map_extra" + consolidate holes bpf: Bloom filter map naming fixups selftests/bpf: Add test cases for struct_ops prog bpf: Add dummy BPF STRUCT_OPS for test purpose bpf: Factor out helpers for ctx access checking bpf: Factor out a helper to prepare trampoline for struct_ops prog selftests, bpf: Fix broken riscv build riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h tools, build: Add RISC-V to HOSTARCH parsing riscv, bpf: Increase the maximum number of iterations selftests, bpf: Add one test for sockmap with strparser selftests, bpf: Fix test_txmsg_ingress_parser error ... ==================== Link: https://lore.kernel.org/r/20211102013123.9005-1-alexei.starovoitov@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> |
|
|
Jakub Kicinski
|
7df621a3ee |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/net/sock.h |
|
|
Toke Høiland-Jørgensen
|
54713c85f5 |
bpf: Fix potential race in tail call compatibility check
Lorenzo noticed that the code testing for program type compatibility of
tail call maps is potentially racy in that two threads could encounter a
map with an unset type simultaneously and both return true even though they
are inserting incompatible programs.
The race window is quite small, but artificially enlarging it by adding a
usleep_range() inside the check in bpf_prog_array_compatible() makes it
trivial to trigger from userspace with a program that does, essentially:
map_fd = bpf_create_map(BPF_MAP_TYPE_PROG_ARRAY, 4, 4, 2, 0);
pid = fork();
if (pid) {
key = 0;
value = xdp_fd;
} else {
key = 1;
value = tc_fd;
}
err = bpf_map_update_elem(map_fd, &key, &value, 0);
While the race window is small, it has potentially serious ramifications in
that triggering it would allow a BPF program to tail call to a program of a
different type. So let's get rid of it by protecting the update with a
spinlock. The commit in the Fixes tag is the last commit that touches the
code in question.
v2:
- Use a spinlock instead of an atomic variable and cmpxchg() (Alexei)
v3:
- Put lock and the members it protects into an embedded 'owner' struct (Daniel)
Fixes:
|
|
Lorenz Bauer
|
fadb7ff1a6 |
bpf: Prevent increasing bpf_jit_limit above max
Restrict bpf_jit_limit to the maximum supported by the arch's JIT. Signed-off-by: Lorenz Bauer <lmb@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211014142554.53120-4-lmb@cloudflare.com |
|
|
Kumar Kartikeya Dwivedi
|
2357672c54 |
bpf: Introduce BPF support for kernel module function calls
This change adds support on the kernel side to allow for BPF programs to call kernel module functions. Userspace will prepare an array of module BTF fds that is passed in during BPF_PROG_LOAD using fd_array parameter. In the kernel, the module BTFs are placed in the auxilliary struct for bpf_prog, and loaded as needed. The verifier then uses insn->off to index into the fd_array. insn->off 0 is reserved for vmlinux BTF (for backwards compat), so userspace must use an fd_array index > 0 for module kfunc support. kfunc_btf_tab is sorted based on offset in an array, and each offset corresponds to one descriptor, with a max limit up to 256 such module BTFs. We also change existing kfunc_tab to distinguish each element based on imm, off pair as each such call will now be distinct. Another change is to check_kfunc_call callback, which now include a struct module * pointer, this is to be used in later patch such that the kfunc_id and module pointer are matched for dynamically registered BTF sets from loadable modules, so that same kfunc_id in two modules doesn't lead to check_kfunc_call succeeding. For the duration of the check_kfunc_call, the reference to struct module exists, as it returns the pointer stored in kfunc_btf_tab. Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20211002011757.311265-2-memxor@gmail.com |
|
|
Jakub Kicinski
|
6b7b0c3091 |
Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:
====================
bpf-next 2021-10-02
We've added 85 non-merge commits during the last 15 day(s) which contain
a total of 132 files changed, 13779 insertions(+), 6724 deletions(-).
The main changes are:
1) Massive update on test_bpf.ko coverage for JITs as preparatory work for
an upcoming MIPS eBPF JIT, from Johan Almbladh.
2) Add a batched interface for RX buffer allocation in AF_XDP buffer pool,
with driver support for i40e and ice from Magnus Karlsson.
3) Add legacy uprobe support to libbpf to complement recently merged legacy
kprobe support, from Andrii Nakryiko.
4) Add bpf_trace_vprintk() as variadic printk helper, from Dave Marchevsky.
5) Support saving the register state in verifier when spilling <8byte bounded
scalar to the stack, from Martin Lau.
6) Add libbpf opt-in for stricter BPF program section name handling as part
of libbpf 1.0 effort, from Andrii Nakryiko.
7) Add a document to help clarifying BPF licensing, from Alexei Starovoitov.
8) Fix skel_internal.h to propagate errno if the loader indicates an internal
error, from Kumar Kartikeya Dwivedi.
9) Fix build warnings with -Wcast-function-type so that the option can later
be enabled by default for the kernel, from Kees Cook.
10) Fix libbpf to ignore STT_SECTION symbols in legacy map definitions as it
otherwise errors out when encountering them, from Toke Høiland-Jørgensen.
11) Teach libbpf to recognize specialized maps (such as for perf RB) and
internally remove BTF type IDs when creating them, from Hengqi Chen.
12) Various fixes and improvements to BPF selftests.
====================
Link: https://lore.kernel.org/r/20211002001327.15169-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
|
Lorenz Bauer
|
8a98ae12fb |
bpf: Exempt CAP_BPF from checks against bpf_jit_limit
When introducing CAP_BPF, bpf_jit_charge_modmem() was not changed to treat
programs with CAP_BPF as privileged for the purpose of JIT memory allocation.
This means that a program without CAP_BPF can block a program with CAP_BPF
from loading a program.
Fix this by checking bpf_capable() in bpf_jit_charge_modmem().
Fixes:
|
|
Dave Marchevsky
|
10aceb629e |
bpf: Add bpf_trace_vprintk helper
This helper is meant to be "bpf_trace_printk, but with proper vararg support". Follow bpf_snprintf's example and take a u64 pseudo-vararg array. Write to /sys/kernel/debug/tracing/trace_pipe using the same mechanism as bpf_trace_printk. The functionality of this helper was requested in the libbpf issue tracker [0]. [0] Closes: https://github.com/libbpf/libbpf/issues/315 Signed-off-by: Dave Marchevsky <davemarchevsky@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210917182911.2426606-4-davemarchevsky@fb.com |
|
Daniel Borkmann
|
f9dabe016b |
bpf: Undo off-by-one in interpreter tail call count limit
The BPF interpreter as well as x86-64 BPF JIT were both in line by allowing up to 33 tail calls (however odd that number may be!). Recently, this was changed for the interpreter to reduce it down to 32 with the assumption that this should have been the actual limit "which is in line with the behavior of the x86 JITs" according to |
|
Andrii Nakryiko
|
82e6b1eee6 |
bpf: Allow to specify user-provided bpf_cookie for BPF perf links
Add ability for users to specify custom u64 value (bpf_cookie) when creating BPF link for perf_event-backed BPF programs (kprobe/uprobe, perf_event, tracepoints). This is useful for cases when the same BPF program is used for attaching and processing invocation of different tracepoints/kprobes/uprobes in a generic fashion, but such that each invocation is distinguished from each other (e.g., BPF program can look up additional information associated with a specific kernel function without having to rely on function IP lookups). This enables new use cases to be implemented simply and efficiently that previously were possible only through code generation (and thus multiple instances of almost identical BPF program) or compilation at runtime (BCC-style) on target hosts (even more expensive resource-wise). For uprobes it is not even possible in some cases to know function IP before hand (e.g., when attaching to shared library without PID filtering, in which case base load address is not known for a library). This is done by storing u64 bpf_cookie in struct bpf_prog_array_item, corresponding to each attached and run BPF program. Given cgroup BPF programs already use two 8-byte pointers for their needs and cgroup BPF programs don't have (yet?) support for bpf_cookie, reuse that space through union of cgroup_storage and new bpf_cookie field. Make it available to kprobe/tracepoint BPF programs through bpf_trace_run_ctx. This is set by BPF_PROG_RUN_ARRAY, used by kprobe/uprobe/tracepoint BPF program execution code, which luckily is now also split from BPF_PROG_RUN_ARRAY_CG. This run context will be utilized by a new BPF helper giving access to this user-provided cookie value from inside a BPF program. Generic perf_event BPF programs will access this value from perf_event itself through passed in BPF program context. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lore.kernel.org/bpf/20210815070609.987780-6-andrii@kernel.org |
|
|
Andrii Nakryiko
|
fb7dd8bca0 |
bpf: Refactor BPF_PROG_RUN into a function
Turn BPF_PROG_RUN into a proper always inlined function. No functional and performance changes are intended, but it makes it much easier to understand what's going on with how BPF programs are actually get executed. It's more obvious what types and callbacks are expected. Also extra () around input parameters can be dropped, as well as `__` variable prefixes intended to avoid naming collisions, which makes the code simpler to read and write. This refactoring also highlighted one extra issue. BPF_PROG_RUN is both a macro and an enum value (BPF_PROG_RUN == BPF_PROG_TEST_RUN). Turning BPF_PROG_RUN into a function causes naming conflict compilation error. So rename BPF_PROG_RUN into lower-case bpf_prog_run(), similar to bpf_prog_run_xdp(), bpf_prog_run_pin_on_cpu(), etc. All existing callers of BPF_PROG_RUN, the macro, are switched to bpf_prog_run() explicitly. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210815070609.987780-2-andrii@kernel.org |
|
|
Jakub Kicinski
|
f4083a752a |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts: drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h |
|
Randy Dunlap
|
019d0454c6 |
bpf, core: Fix kernel-doc notation
Fix kernel-doc warnings in kernel/bpf/core.c (found by scripts/kernel-doc and W=1 builds). That is, correct a function name in a comment and add return descriptions for 2 functions. Fixes these kernel-doc warnings: kernel/bpf/core.c:1372: warning: expecting prototype for __bpf_prog_run(). Prototype was for ___bpf_prog_run() instead kernel/bpf/core.c:1372: warning: No description found for return value of '___bpf_prog_run' kernel/bpf/core.c:1883: warning: No description found for return value of 'bpf_prog_select_runtime' Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20210809215229.7556-1-rdunlap@infradead.org |
|
Johan Almbladh
|
b61a28cf11 |
bpf: Fix off-by-one in tail call count limiting
Before, the interpreter allowed up to MAX_TAIL_CALL_CNT + 1 tail calls. Now precisely MAX_TAIL_CALL_CNT is allowed, which is in line with the behavior of the x86 JITs. Signed-off-by: Johan Almbladh <johan.almbladh@anyfinetworks.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210728164741.350370-1-johan.almbladh@anyfinetworks.com |
|
|
Daniel Borkmann
|
f5e81d1117 |
bpf: Introduce BPF nospec instruction for mitigating Spectre v4
In case of JITs, each of the JIT backends compiles the BPF nospec instruction /either/ to a machine instruction which emits a speculation barrier /or/ to /no/ machine instruction in case the underlying architecture is not affected by Speculative Store Bypass or has different mitigations in place already. This covers both x86 and (implicitly) arm64: In case of x86, we use 'lfence' instruction for mitigation. In case of arm64, we rely on the firmware mitigation as controlled via the ssbd kernel parameter. Whenever the mitigation is enabled, it works for all of the kernel code with no need to provide any additional instructions here (hence only comment in arm64 JIT). Other archs can follow as needed. The BPF nospec instruction is specifically targeting Spectre v4 since i) we don't use a serialization barrier for the Spectre v1 case, and ii) mitigation instructions for v1 and v4 might be different on some archs. The BPF nospec is required for a future commit, where the BPF verifier does annotate intermediate BPF programs with speculation barriers. Co-developed-by: Piotr Krysiuk <piotras@gmail.com> Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Piotr Krysiuk <piotras@gmail.com> Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de> Acked-by: Alexei Starovoitov <ast@kernel.org> |
|
John Fastabend
|
f263a81451 |
bpf: Track subprog poke descriptors correctly and fix use-after-free
Subprograms are calling map_poke_track(), but on program release there is no hook to call map_poke_untrack(). However, on program release, the aux memory (and poke descriptor table) is freed even though we still have a reference to it in the element list of the map aux data. When we run map_poke_run(), we then end up accessing free'd memory, triggering KASAN in prog_array_map_poke_run(): [...] [ 402.824689] BUG: KASAN: use-after-free in prog_array_map_poke_run+0xc2/0x34e [ 402.824698] Read of size 4 at addr ffff8881905a7940 by task hubble-fgs/4337 [ 402.824705] CPU: 1 PID: 4337 Comm: hubble-fgs Tainted: G I 5.12.0+ #399 [ 402.824715] Call Trace: [ 402.824719] dump_stack+0x93/0xc2 [ 402.824727] print_address_description.constprop.0+0x1a/0x140 [ 402.824736] ? prog_array_map_poke_run+0xc2/0x34e [ 402.824740] ? prog_array_map_poke_run+0xc2/0x34e [ 402.824744] kasan_report.cold+0x7c/0xd8 [ 402.824752] ? prog_array_map_poke_run+0xc2/0x34e [ 402.824757] prog_array_map_poke_run+0xc2/0x34e [ 402.824765] bpf_fd_array_map_update_elem+0x124/0x1a0 [...] The elements concerned are walked as follows: for (i = 0; i < elem->aux->size_poke_tab; i++) { poke = &elem->aux->poke_tab[i]; [...] The access to size_poke_tab is a 4 byte read, verified by checking offsets in the KASAN dump: [ 402.825004] The buggy address belongs to the object at ffff8881905a7800 which belongs to the cache kmalloc-1k of size 1024 [ 402.825008] The buggy address is located 320 bytes inside of 1024-byte region [ffff8881905a7800, ffff8881905a7c00) The pahole output of bpf_prog_aux: struct bpf_prog_aux { [...] /* --- cacheline 5 boundary (320 bytes) --- */ u32 size_poke_tab; /* 320 4 */ [...] In general, subprograms do not necessarily manage their own data structures. For example, BTF func_info and linfo are just pointers to the main program structure. This allows reference counting and cleanup to be done on the latter which simplifies their management a bit. The aux->poke_tab struct, however, did not follow this logic. The initial proposed fix for this use-after-free bug further embedded poke data tracking into the subprogram with proper reference counting. However, Daniel and Alexei questioned why we were treating these objects special; I agree, its unnecessary. The fix here removes the per subprogram poke table allocation and map tracking and instead simply points the aux->poke_tab pointer at the main programs poke table. This way, map tracking is simplified to the main program and we do not need to manage them per subprogram. This also means, bpf_prog_free_deferred(), which unwinds the program reference counting and kfrees objects, needs to ensure that we don't try to double free the poke_tab when free'ing the subprog structures. This is easily solved by NULL'ing the poke_tab pointer. The second detail is to ensure that per subprogram JIT logic only does fixups on poke_tab[] entries it owns. To do this, we add a pointer in the poke structure to point at the subprogram value so JITs can easily check while walking the poke_tab structure if the current entry belongs to the current program. The aux pointer is stable and therefore suitable for such comparison. On the jit_subprogs() error path, we omit cleaning up the poke->aux field because these are only ever referenced from the JIT side, but on error we will never make it to the JIT, so its fine to leave them dangling. Removing these pointers would complicate the error path for no reason. However, we do need to untrack all poke descriptors from the main program as otherwise they could race with the freeing of JIT memory from the subprograms. Lastly, |
|
|
Daniel Borkmann
|
28131e9d93 |
bpf: Fix up register-based shifts in interpreter to silence KUBSAN
syzbot reported a shift-out-of-bounds that KUBSAN observed in the interpreter: [...] UBSAN: shift-out-of-bounds in kernel/bpf/core.c:1420:2 shift exponent 255 is too large for 64-bit type 'long long unsigned int' CPU: 1 PID: 11097 Comm: syz-executor.4 Not tainted 5.12.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:327 ___bpf_prog_run.cold+0x19/0x56c kernel/bpf/core.c:1420 __bpf_prog_run32+0x8f/0xd0 kernel/bpf/core.c:1735 bpf_dispatcher_nop_func include/linux/bpf.h:644 [inline] bpf_prog_run_pin_on_cpu include/linux/filter.h:624 [inline] bpf_prog_run_clear_cb include/linux/filter.h:755 [inline] run_filter+0x1a1/0x470 net/packet/af_packet.c:2031 packet_rcv+0x313/0x13e0 net/packet/af_packet.c:2104 dev_queue_xmit_nit+0x7c2/0xa90 net/core/dev.c:2387 xmit_one net/core/dev.c:3588 [inline] dev_hard_start_xmit+0xad/0x920 net/core/dev.c:3609 __dev_queue_xmit+0x2121/0x2e00 net/core/dev.c:4182 __bpf_tx_skb net/core/filter.c:2116 [inline] __bpf_redirect_no_mac net/core/filter.c:2141 [inline] __bpf_redirect+0x548/0xc80 net/core/filter.c:2164 ____bpf_clone_redirect net/core/filter.c:2448 [inline] bpf_clone_redirect+0x2ae/0x420 net/core/filter.c:2420 ___bpf_prog_run+0x34e1/0x77d0 kernel/bpf/core.c:1523 __bpf_prog_run512+0x99/0xe0 kernel/bpf/core.c:1737 bpf_dispatcher_nop_func include/linux/bpf.h:644 [inline] bpf_test_run+0x3ed/0xc50 net/bpf/test_run.c:50 bpf_prog_test_run_skb+0xabc/0x1c50 net/bpf/test_run.c:582 bpf_prog_test_run kernel/bpf/syscall.c:3127 [inline] __do_sys_bpf+0x1ea9/0x4f00 kernel/bpf/syscall.c:4406 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xae [...] Generally speaking, KUBSAN reports from the kernel should be fixed. However, in case of BPF, this particular report caused concerns since the large shift is not wrong from BPF point of view, just undefined. In the verifier, K-based shifts that are >= {64,32} (depending on the bitwidth of the instruction) are already rejected. The register-based cases were not given their content might not be known at verification time. Ideas such as verifier instruction rewrite with an additional AND instruction for the source register were brought up, but regularly rejected due to the additional runtime overhead they incur. As Edward Cree rightly put it: Shifts by more than insn bitness are legal in the BPF ISA; they are implementation-defined behaviour [of the underlying architecture], rather than UB, and have been made legal for performance reasons. Each of the JIT backends compiles the BPF shift operations to machine instructions which produce implementation-defined results in such a case; the resulting contents of the register may be arbitrary but program behaviour as a whole remains defined. Guard checks in the fast path (i.e. affecting JITted code) will thus not be accepted. The case of division by zero is not truly analogous here, as division instructions on many of the JIT-targeted architectures will raise a machine exception / fault on division by zero, whereas (to the best of my knowledge) none will do so on an out-of-bounds shift. Given the KUBSAN report only affects the BPF interpreter, but not JITs, one solution is to add the ANDs with 63 or 31 into ___bpf_prog_run(). That would make the shifts defined, and thus shuts up KUBSAN, and the compiler would optimize out the AND on any CPU that interprets the shift amounts modulo the width anyway (e.g., confirmed from disassembly that on x86-64 and arm64 the generated interpreter code is the same before and after this fix). The BPF interpreter is slow path, and most likely compiled out anyway as distros select BPF_JIT_ALWAYS_ON to avoid speculative execution of BPF instructions by the interpreter. Given the main argument was to avoid sacrificing performance, the fact that the AND is optimized away from compiler for mainstream archs helps as well as a solution moving forward. Also add a comment on LSH/RSH/ARSH translation for JIT authors to provide guidance when they see the ___bpf_prog_run() interpreter code and use it as a model for a new JIT backend. Reported-by: syzbot+bed360704c521841c85d@syzkaller.appspotmail.com Reported-by: Kurt Manucredo <fuzzybritches0@gmail.com> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Co-developed-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Tested-by: syzbot+bed360704c521841c85d@syzkaller.appspotmail.com Cc: Edward Cree <ecree.xilinx@gmail.com> Link: https://lore.kernel.org/bpf/0000000000008f912605bd30d5d7@google.com Link: https://lore.kernel.org/bpf/bac16d8d-c174-bdc4-91bd-bfa62b410190@gmail.com |
|
He Fengqing
|
2ec9898e9c |
bpf: Remove unused parameter from ___bpf_prog_run
'stack' parameter is not used in ___bpf_prog_run() after
|
|
|
Martin KaFai Lau
|
e6ac2450d6 |
bpf: Support bpf program calling kernel function
This patch adds support to BPF verifier to allow bpf program calling kernel function directly. The use case included in this set is to allow bpf-tcp-cc to directly call some tcp-cc helper functions (e.g. "tcp_cong_avoid_ai()"). Those functions have already been used by some kernel tcp-cc implementations. This set will also allow the bpf-tcp-cc program to directly call the kernel tcp-cc implementation, For example, a bpf_dctcp may only want to implement its own dctcp_cwnd_event() and reuse other dctcp_*() directly from the kernel tcp_dctcp.c instead of reimplementing (or copy-and-pasting) them. The tcp-cc kernel functions mentioned above will be white listed for the struct_ops bpf-tcp-cc programs to use in a later patch. The white listed functions are not bounded to a fixed ABI contract. Those functions have already been used by the existing kernel tcp-cc. If any of them has changed, both in-tree and out-of-tree kernel tcp-cc implementations have to be changed. The same goes for the struct_ops bpf-tcp-cc programs which have to be adjusted accordingly. This patch is to make the required changes in the bpf verifier. First change is in btf.c, it adds a case in "btf_check_func_arg_match()". When the passed in "btf->kernel_btf == true", it means matching the verifier regs' states with a kernel function. This will handle the PTR_TO_BTF_ID reg. It also maps PTR_TO_SOCK_COMMON, PTR_TO_SOCKET, and PTR_TO_TCP_SOCK to its kernel's btf_id. In the later libbpf patch, the insn calling a kernel function will look like: insn->code == (BPF_JMP | BPF_CALL) insn->src_reg == BPF_PSEUDO_KFUNC_CALL /* <- new in this patch */ insn->imm == func_btf_id /* btf_id of the running kernel */ [ For the future calling function-in-kernel-module support, an array of module btf_fds can be passed at the load time and insn->off can be used to index into this array. ] At the early stage of verifier, the verifier will collect all kernel function calls into "struct bpf_kfunc_desc". Those descriptors are stored in "prog->aux->kfunc_tab" and will be available to the JIT. Since this "add" operation is similar to the current "add_subprog()" and looking for the same insn->code, they are done together in the new "add_subprog_and_kfunc()". In the "do_check()" stage, the new "check_kfunc_call()" is added to verify the kernel function call instruction: 1. Ensure the kernel function can be used by a particular BPF_PROG_TYPE. A new bpf_verifier_ops "check_kfunc_call" is added to do that. The bpf-tcp-cc struct_ops program will implement this function in a later patch. 2. Call "btf_check_kfunc_args_match()" to ensure the regs can be used as the args of a kernel function. 3. Mark the regs' type, subreg_def, and zext_dst. At the later do_misc_fixups() stage, the new fixup_kfunc_call() will replace the insn->imm with the function address (relative to __bpf_call_base). If needed, the jit can find the btf_func_model by calling the new bpf_jit_find_kfunc_model(prog, insn). With the imm set to the function address, "bpftool prog dump xlated" will be able to display the kernel function calls the same way as it displays other bpf helper calls. gpl_compatible program is required to call kernel function. This feature currently requires JIT. The verifier selftests are adjusted because of the changes in the verbose log in add_subprog_and_kfunc(). Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210325015142.1544736-1-kafai@fb.com |
|
|
Martin KaFai Lau
|
e16301fbe1 |
bpf: Simplify freeing logic in linfo and jited_linfo
This patch simplifies the linfo freeing logic by combining "bpf_prog_free_jited_linfo()" and "bpf_prog_free_unused_jited_linfo()" into the new "bpf_prog_jit_attempt_done()". It is a prep work for the kernel function call support. In a later patch, freeing the kernel function call descriptors will also be done in the "bpf_prog_jit_attempt_done()". "bpf_prog_free_linfo()" is removed since it is only called by "__bpf_prog_put_noref()". The kvfree() are directly called instead. It also takes this chance to s/kcalloc/kvcalloc/ for the jited_linfo allocation. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210325015130.1544323-1-kafai@fb.com |
|
|
Alexei Starovoitov
|
e21aa34178 |
bpf: Fix fexit trampoline.
The fexit/fmod_ret programs can be attached to kernel functions that can sleep.
The synchronize_rcu_tasks() will not wait for such tasks to complete.
In such case the trampoline image will be freed and when the task
wakes up the return IP will point to freed memory causing the crash.
Solve this by adding percpu_ref_get/put for the duration of trampoline
and separate trampoline vs its image life times.
The "half page" optimization has to be removed, since
first_half->second_half->first_half transition cannot be guaranteed to
complete in deterministic time. Every trampoline update becomes a new image.
The image with fmod_ret or fexit progs will be freed via percpu_ref_kill and
call_rcu_tasks. Together they will wait for the original function and
trampoline asm to complete. The trampoline is patched from nop to jmp to skip
fexit progs. They are freed independently from the trampoline. The image with
fentry progs only will be freed via call_rcu_tasks_trace+call_rcu_tasks which
will wait for both sleepable and non-sleepable progs to complete.
Fixes:
|
|
Brendan Jackman
|
39491867ac |
bpf: Explicitly zero-extend R0 after 32-bit cmpxchg
As pointed out by Ilya and explained in the new comment, there's a
discrepancy between x86 and BPF CMPXCHG semantics: BPF always loads
the value from memory into r0, while x86 only does so when r0 and the
value in memory are different. The same issue affects s390.
At first this might sound like pure semantics, but it makes a real
difference when the comparison is 32-bit, since the load will
zero-extend r0/rax.
The fix is to explicitly zero-extend rax after doing such a
CMPXCHG. Since this problem affects multiple archs, this is done in
the verifier by patching in a BPF_ZEXT_REG instruction after every
32-bit cmpxchg. Any archs that don't need such manual zero-extension
can do a look-ahead with insn_is_zext to skip the unnecessary mov.
Note this still goes on top of Ilya's patch:
https://lore.kernel.org/bpf/20210301154019.129110-1-iii@linux.ibm.com/T/#u
Differences v5->v6[1]:
- Moved is_cmpxchg_insn and ensured it can be safely re-used. Also renamed it
and removed 'inline' to match the style of the is_*_function helpers.
- Fixed up comments in verifier test (thanks for the careful review, Martin!)
Differences v4->v5[1]:
- Moved the logic entirely into opt_subreg_zext_lo32_rnd_hi32, thanks to Martin
for suggesting this.
Differences v3->v4[1]:
- Moved the optimization against pointless zext into the correct place:
opt_subreg_zext_lo32_rnd_hi32 is called _after_ fixup_bpf_calls.
Differences v2->v3[1]:
- Moved patching into fixup_bpf_calls (patch incoming to rename this function)
- Added extra commentary on bpf_jit_needs_zext
- Added check to avoid adding a pointless zext(r0) if there's already one there.
Difference v1->v2[1]: Now solved centrally in the verifier instead of
specifically for the x86 JIT. Thanks to Ilya and Daniel for the suggestions!
[1] v5: https://lore.kernel.org/bpf/CA+i-1C3ytZz6FjcPmUg5s4L51pMQDxWcZNvM86w4RHZ_o2khwg@mail.gmail.com/T/#t
v4: https://lore.kernel.org/bpf/CA+i-1C3ytZz6FjcPmUg5s4L51pMQDxWcZNvM86w4RHZ_o2khwg@mail.gmail.com/T/#t
v3: https://lore.kernel.org/bpf/08669818-c99d-0d30-e1db-53160c063611@iogearbox.net/T/#t
v2: https://lore.kernel.org/bpf/08669818-c99d-0d30-e1db-53160c063611@iogearbox.net/T/#t
v1: https://lore.kernel.org/bpf/d7ebaefb-bfd6-a441-3ff2-2fdfe699b1d2@iogearbox.net/T/#t
Reported-by: Ilya Leoshkevich <iii@linux.ibm.com>
Fixes:
|
|
Cong Wang
|
53f523f305 |
bpf: Clear percpu pointers in bpf_prog_clone_free()
Similar to bpf_prog_realloc(), bpf_prog_clone_create() also copies the percpu pointers, but the clone still shares them with the original prog, so we have to clear these two percpu pointers in bpf_prog_clone_free(). Otherwise we would get a double free: BUG: kernel NULL pointer dereference, address: 0000000000000000 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP PTI CPU: 13 PID: 8140 Comm: kworker/13:247 Kdump: loaded Tainted: G W OE 5.11.0-rc4.bm.1-amd64+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 test_bpf: #1 TXA Workqueue: events bpf_prog_free_deferred RIP: 0010:percpu_ref_get_many.constprop.97+0x42/0xf0 Code: [...] RSP: 0018:ffffa6bce1f9bda0 EFLAGS: 00010002 RAX: 0000000000000001 RBX: 0000000000000000 RCX: 00000000021dfc7b RDX: ffffffffae2eeb90 RSI: 867f92637e338da5 RDI: 0000000000000046 RBP: ffffa6bce1f9bda8 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000046 R11: 0000000000000000 R12: 0000000000000280 R13: 0000000000000000 R14: 0000000000000000 R15: ffff9b5f3ffdedc0 FS: 0000000000000000(0000) GS:ffff9b5f2fb40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000027c36c002 CR4: 00000000003706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: refill_obj_stock+0x5e/0xd0 free_percpu+0xee/0x550 __bpf_prog_free+0x4d/0x60 process_one_work+0x26a/0x590 worker_thread+0x3c/0x390 ? process_one_work+0x590/0x590 kthread+0x130/0x150 ? kthread_park+0x80/0x80 ret_from_fork+0x1f/0x30 This bug is 100% reproducible with test_kmod.sh. Fixes: |
|
|
Alexei Starovoitov
|
1336c66247 |
bpf: Clear per_cpu pointers during bpf_prog_realloc
bpf_prog_realloc copies contents of struct bpf_prog. The pointers have to be cleared before freeing old struct. Reported-by: Ilya Leoshkevich <iii@linux.ibm.com> Fixes: |
|
|
Alexei Starovoitov
|
ca06f55b90 |
bpf: Add per-program recursion prevention mechanism
Since both sleepable and non-sleepable programs execute under migrate_disable add recursion prevention mechanism to both types of programs when they're executed via bpf trampoline. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210210033634.62081-5-alexei.starovoitov@gmail.com |
|
|
Alexei Starovoitov
|
700d4796ef |
bpf: Optimize program stats
Move bpf_prog_stats from prog->aux into prog to avoid one extra load in critical path of program execution. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20210210033634.62081-2-alexei.starovoitov@gmail.com |
|
|
Brendan Jackman
|
981f94c3e9 |
bpf: Add bitwise atomic instructions
This adds instructions for atomic[64]_[fetch_]and atomic[64]_[fetch_]or atomic[64]_[fetch_]xor All these operations are isomorphic enough to implement with the same verifier, interpreter, and x86 JIT code, hence being a single commit. The main interesting thing here is that x86 doesn't directly support the fetch_ version these operations, so we need to generate a CMPXCHG loop in the JIT. This requires the use of two temporary registers, IIUC it's safe to use BPF_REG_AX and x86's AUX_REG for this purpose. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-10-jackmanb@google.com |
|
|
Brendan Jackman
|
462910670e |
bpf: Pull out a macro for interpreting atomic ALU operations
Since the atomic operations that are added in subsequent commits are all isomorphic with BPF_ADD, pull out a macro to avoid the interpreter becoming dominated by lines of atomic-related code. Note that this sacrificies interpreter performance (combining STX_ATOMIC_W and STX_ATOMIC_DW into single switch case means that we need an extra conditional branch to differentiate them) in favour of compact and (relatively!) simple C code. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-9-jackmanb@google.com |
|
|
Brendan Jackman
|
5ffa25502b |
bpf: Add instructions for atomic_[cmp]xchg
This adds two atomic opcodes, both of which include the BPF_FETCH flag. XCHG without the BPF_FETCH flag would naturally encode atomic_set. This is not supported because it would be of limited value to userspace (it doesn't imply any barriers). CMPXCHG without BPF_FETCH woulud be an atomic compare-and-write. We don't have such an operation in the kernel so it isn't provided to BPF either. There are two significant design decisions made for the CMPXCHG instruction: - To solve the issue that this operation fundamentally has 3 operands, but we only have two register fields. Therefore the operand we compare against (the kernel's API calls it 'old') is hard-coded to be R0. x86 has similar design (and A64 doesn't have this problem). A potential alternative might be to encode the other operand's register number in the immediate field. - The kernel's atomic_cmpxchg returns the old value, while the C11 userspace APIs return a boolean indicating the comparison result. Which should BPF do? A64 returns the old value. x86 returns the old value in the hard-coded register (and also sets a flag). That means return-old-value is easier to JIT, so that's what we use. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-8-jackmanb@google.com |
|
|
Brendan Jackman
|
5ca419f286 |
bpf: Add BPF_FETCH field / create atomic_fetch_add instruction
The BPF_FETCH field can be set in bpf_insn.imm, for BPF_ATOMIC instructions, in order to have the previous value of the atomically-modified memory location loaded into the src register after an atomic op is carried out. Suggested-by: Yonghong Song <yhs@fb.com> Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-7-jackmanb@google.com |
|
|
Brendan Jackman
|
91c960b005 |
bpf: Rename BPF_XADD and prepare to encode other atomics in .imm
A subsequent patch will add additional atomic operations. These new operations will use the same opcode field as the existing XADD, with the immediate discriminating different operations. In preparation, rename the instruction mode BPF_ATOMIC and start calling the zero immediate BPF_ADD. This is possible (doesn't break existing valid BPF progs) because the immediate field is currently reserved MBZ and BPF_ADD is zero. All uses are removed from the tree but the BPF_XADD definition is kept around to avoid breaking builds for people including kernel headers. Signed-off-by: Brendan Jackman <jackmanb@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Björn Töpel <bjorn.topel@gmail.com> Link: https://lore.kernel.org/bpf/20210114181751.768687-5-jackmanb@google.com |
|
|
Andrii Nakryiko
|
541c3bad8d |
bpf: Support BPF ksym variables in kernel modules
Add support for directly accessing kernel module variables from BPF programs using special ldimm64 instructions. This functionality builds upon vmlinux ksym support, but extends ldimm64 with src_reg=BPF_PSEUDO_BTF_ID to allow specifying kernel module BTF's FD in insn[1].imm field. During BPF program load time, verifier will resolve FD to BTF object and will take reference on BTF object itself and, for module BTFs, corresponding module as well, to make sure it won't be unloaded from under running BPF program. The mechanism used is similar to how bpf_prog keeps track of used bpf_maps. One interesting change is also in how per-CPU variable is determined. The logic is to find .data..percpu data section in provided BTF, but both vmlinux and module each have their own .data..percpu entries in BTF. So for module's case, the search for DATASEC record needs to look at only module's added BTF types. This is implemented with custom search function. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Hao Luo <haoluo@google.com> Link: https://lore.kernel.org/bpf/20210112075520.4103414-6-andrii@kernel.org |
|
Roman Gushchin
|
3ac1f01b43 |
bpf: Eliminate rlimit-based memory accounting for bpf progs
Do not use rlimit-based memory accounting for bpf progs. It has been replaced with memcg-based memory accounting. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20201201215900.3569844-34-guro@fb.com |
|
|
Roman Gushchin
|
ddf8503c7c |
bpf: Memcg-based memory accounting for bpf progs
Include memory used by bpf programs into the memcg-based accounting. This includes the memory used by programs itself, auxiliary data, statistics and bpf line info. A memory cgroup containing the process which loads the program is getting charged. Signed-off-by: Roman Gushchin <guro@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20201201215900.3569844-6-guro@fb.com |
|
Dmitrii Banshchikov
|
d055126180 |
bpf: Add bpf_ktime_get_coarse_ns helper
The helper uses CLOCK_MONOTONIC_COARSE source of time that is less accurate but more performant. We have a BPF CGROUP_SKB firewall that supports event logging through bpf_perf_event_output(). Each event has a timestamp and currently we use bpf_ktime_get_ns() for it. Use of bpf_ktime_get_coarse_ns() saves ~15-20 ns in time required for event logging. bpf_ktime_get_ns(): EgressLogByRemoteEndpoint 113.82ns 8.79M bpf_ktime_get_coarse_ns(): EgressLogByRemoteEndpoint 95.40ns 10.48M Signed-off-by: Dmitrii Banshchikov <me@ubique.spb.ru> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20201117184549.257280-1-me@ubique.spb.ru |
|
Ard Biesheuvel
|
080b6f4076 |
bpf: Don't rely on GCC __attribute__((optimize)) to disable GCSE
Commit |
|
|
Linus Torvalds
|
9ff9b0d392 |
networking changes for the 5.10 merge window
Add redirect_neigh() BPF packet redirect helper, allowing to limit stack traversal in common container configs and improving TCP back-pressure. Daniel reports ~10Gbps => ~15Gbps single stream TCP performance gain. Expand netlink policy support and improve policy export to user space. (Ge)netlink core performs request validation according to declared policies. Expand the expressiveness of those policies (min/max length and bitmasks). Allow dumping policies for particular commands. This is used for feature discovery by user space (instead of kernel version parsing or trial and error). Support IGMPv3/MLDv2 multicast listener discovery protocols in bridge. Allow more than 255 IPv4 multicast interfaces. Add support for Type of Service (ToS) reflection in SYN/SYN-ACK packets of TCPv6. In Multi-patch TCP (MPTCP) support concurrent transmission of data on multiple subflows in a load balancing scenario. Enhance advertising addresses via the RM_ADDR/ADD_ADDR options. Support SMC-Dv2 version of SMC, which enables multi-subnet deployments. Allow more calls to same peer in RxRPC. Support two new Controller Area Network (CAN) protocols - CAN-FD and ISO 15765-2:2016. Add xfrm/IPsec compat layer, solving the 32bit user space on 64bit kernel problem. Add TC actions for implementing MPLS L2 VPNs. Improve nexthop code - e.g. handle various corner cases when nexthop objects are removed from groups better, skip unnecessary notifications and make it easier to offload nexthops into HW by converting to a blocking notifier. Support adding and consuming TCP header options by BPF programs, opening the doors for easy experimental and deployment-specific TCP option use. Reorganize TCP congestion control (CC) initialization to simplify life of TCP CC implemented in BPF. Add support for shipping BPF programs with the kernel and loading them early on boot via the User Mode Driver mechanism, hence reusing all the user space infra we have. Support sleepable BPF programs, initially targeting LSM and tracing. Add bpf_d_path() helper for returning full path for given 'struct path'. Make bpf_tail_call compatible with bpf-to-bpf calls. Allow BPF programs to call map_update_elem on sockmaps. Add BPF Type Format (BTF) support for type and enum discovery, as well as support for using BTF within the kernel itself (current use is for pretty printing structures). Support listing and getting information about bpf_links via the bpf syscall. Enhance kernel interfaces around NIC firmware update. Allow specifying overwrite mask to control if settings etc. are reset during update; report expected max time operation may take to users; support firmware activation without machine reboot incl. limits of how much impact reset may have (e.g. dropping link or not). Extend ethtool configuration interface to report IEEE-standard counters, to limit the need for per-vendor logic in user space. Adopt or extend devlink use for debug, monitoring, fw update in many drivers (dsa loop, ice, ionic, sja1105, qed, mlxsw, mv88e6xxx, dpaa2-eth). In mlxsw expose critical and emergency SFP module temperature alarms. Refactor port buffer handling to make the defaults more suitable and support setting these values explicitly via the DCBNL interface. Add XDP support for Intel's igb driver. Support offloading TC flower classification and filtering rules to mscc_ocelot switches. Add PTP support for Marvell Octeontx2 and PP2.2 hardware, as well as fixed interval period pulse generator and one-step timestamping in dpaa-eth. Add support for various auth offloads in WiFi APs, e.g. SAE (WPA3) offload. Add Lynx PHY/PCS MDIO module, and convert various drivers which have this HW to use it. Convert mvpp2 to split PCS. Support Marvell Prestera 98DX3255 24-port switch ASICs, as well as 7-port Mediatek MT7531 IP. Add initial support for QCA6390 and IPQ6018 in ath11k WiFi driver, and wcn3680 support in wcn36xx. Improve performance for packets which don't require much offloads on recent Mellanox NICs by 20% by making multiple packets share a descriptor entry. Move chelsio inline crypto drivers (for TLS and IPsec) from the crypto subtree to drivers/net. Move MDIO drivers out of the phy directory. Clean up a lot of W=1 warnings, reportedly the actively developed subsections of networking drivers should now build W=1 warning free. Make sure drivers don't use in_interrupt() to dynamically adapt their code. Convert tasklets to use new tasklet_setup API (sadly this conversion is not yet complete). Signed-off-by: Jakub Kicinski <kuba@kernel.org> -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEE6jPA+I1ugmIBA4hXMUZtbf5SIrsFAl+ItRwACgkQMUZtbf5S IrtTMg//UxpdR/MirT1DatBU0K/UGAZY82hV7F/UC8tPgjfHZeHvWlDFxfi3YP81 PtPKbhRZ7DhwBXefUp6nY3UdvjftrJK2lJm8prJUPSsZRye8Wlcb7y65q7/P2y2U Efucyopg6RUrmrM0DUsIGYGJgylQLHnMYUl/keCsD4t5Bp4ksyi9R2t5eitGoWzh r3QGdbSa0AuWx4iu0i+tqp6Tj0ekMBMXLVb35dtU1t0joj2KTNEnSgABN3prOa8E iWYf2erOau68Ogp3yU3miCy0ZU4p/7qGHTtzbcp677692P/ekak6+zmfHLT9/Pjy 2Stq2z6GoKuVxdktr91D9pA3jxG4LxSJmr0TImcGnXbvkMP3Ez3g9RrpV5fn8j6F mZCH8TKZAoD5aJrAJAMkhZmLYE1pvDa7KolSk8WogXrbCnTEb5Nv8FHTS1Qnk3yl wSKXuvutFVNLMEHCnWQLtODbTST9DI/aOi6EctPpuOA/ZyL1v3pl+gfp37S+LUTe owMnT/7TdvKaTD0+gIyU53M6rAWTtr5YyRQorX9awIu/4Ha0F0gYD7BJZQUGtegp HzKt59NiSrFdbSH7UdyemdBF4LuCgIhS7rgfeoUXMXmuPHq7eHXyHZt5dzPPa/xP 81P0MAvdpFVwg8ij2yp2sHS7sISIRKq17fd1tIewUabxQbjXqPc= =bc1U -----END PGP SIGNATURE----- Merge tag 'net-next-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next Pull networking updates from Jakub Kicinski: - Add redirect_neigh() BPF packet redirect helper, allowing to limit stack traversal in common container configs and improving TCP back-pressure. Daniel reports ~10Gbps => ~15Gbps single stream TCP performance gain. - Expand netlink policy support and improve policy export to user space. (Ge)netlink core performs request validation according to declared policies. Expand the expressiveness of those policies (min/max length and bitmasks). Allow dumping policies for particular commands. This is used for feature discovery by user space (instead of kernel version parsing or trial and error). - Support IGMPv3/MLDv2 multicast listener discovery protocols in bridge. - Allow more than 255 IPv4 multicast interfaces. - Add support for Type of Service (ToS) reflection in SYN/SYN-ACK packets of TCPv6. - In Multi-patch TCP (MPTCP) support concurrent transmission of data on multiple subflows in a load balancing scenario. Enhance advertising addresses via the RM_ADDR/ADD_ADDR options. - Support SMC-Dv2 version of SMC, which enables multi-subnet deployments. - Allow more calls to same peer in RxRPC. - Support two new Controller Area Network (CAN) protocols - CAN-FD and ISO 15765-2:2016. - Add xfrm/IPsec compat layer, solving the 32bit user space on 64bit kernel problem. - Add TC actions for implementing MPLS L2 VPNs. - Improve nexthop code - e.g. handle various corner cases when nexthop objects are removed from groups better, skip unnecessary notifications and make it easier to offload nexthops into HW by converting to a blocking notifier. - Support adding and consuming TCP header options by BPF programs, opening the doors for easy experimental and deployment-specific TCP option use. - Reorganize TCP congestion control (CC) initialization to simplify life of TCP CC implemented in BPF. - Add support for shipping BPF programs with the kernel and loading them early on boot via the User Mode Driver mechanism, hence reusing all the user space infra we have. - Support sleepable BPF programs, initially targeting LSM and tracing. - Add bpf_d_path() helper for returning full path for given 'struct path'. - Make bpf_tail_call compatible with bpf-to-bpf calls. - Allow BPF programs to call map_update_elem on sockmaps. - Add BPF Type Format (BTF) support for type and enum discovery, as well as support for using BTF within the kernel itself (current use is for pretty printing structures). - Support listing and getting information about bpf_links via the bpf syscall. - Enhance kernel interfaces around NIC firmware update. Allow specifying overwrite mask to control if settings etc. are reset during update; report expected max time operation may take to users; support firmware activation without machine reboot incl. limits of how much impact reset may have (e.g. dropping link or not). - Extend ethtool configuration interface to report IEEE-standard counters, to limit the need for per-vendor logic in user space. - Adopt or extend devlink use for debug, monitoring, fw update in many drivers (dsa loop, ice, ionic, sja1105, qed, mlxsw, mv88e6xxx, dpaa2-eth). - In mlxsw expose critical and emergency SFP module temperature alarms. Refactor port buffer handling to make the defaults more suitable and support setting these values explicitly via the DCBNL interface. - Add XDP support for Intel's igb driver. - Support offloading TC flower classification and filtering rules to mscc_ocelot switches. - Add PTP support for Marvell Octeontx2 and PP2.2 hardware, as well as fixed interval period pulse generator and one-step timestamping in dpaa-eth. - Add support for various auth offloads in WiFi APs, e.g. SAE (WPA3) offload. - Add Lynx PHY/PCS MDIO module, and convert various drivers which have this HW to use it. Convert mvpp2 to split PCS. - Support Marvell Prestera 98DX3255 24-port switch ASICs, as well as 7-port Mediatek MT7531 IP. - Add initial support for QCA6390 and IPQ6018 in ath11k WiFi driver, and wcn3680 support in wcn36xx. - Improve performance for packets which don't require much offloads on recent Mellanox NICs by 20% by making multiple packets share a descriptor entry. - Move chelsio inline crypto drivers (for TLS and IPsec) from the crypto subtree to drivers/net. Move MDIO drivers out of the phy directory. - Clean up a lot of W=1 warnings, reportedly the actively developed subsections of networking drivers should now build W=1 warning free. - Make sure drivers don't use in_interrupt() to dynamically adapt their code. Convert tasklets to use new tasklet_setup API (sadly this conversion is not yet complete). * tag 'net-next-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2583 commits) Revert "bpfilter: Fix build error with CONFIG_BPFILTER_UMH" net, sockmap: Don't call bpf_prog_put() on NULL pointer bpf, selftest: Fix flaky tcp_hdr_options test when adding addr to lo bpf, sockmap: Add locking annotations to iterator netfilter: nftables: allow re-computing sctp CRC-32C in 'payload' statements net: fix pos incrementment in ipv6_route_seq_next net/smc: fix invalid return code in smcd_new_buf_create() net/smc: fix valid DMBE buffer sizes net/smc: fix use-after-free of delayed events bpfilter: Fix build error with CONFIG_BPFILTER_UMH cxgb4/ch_ipsec: Replace the module name to ch_ipsec from chcr net: sched: Fix suspicious RCU usage while accessing tcf_tunnel_info bpf: Fix register equivalence tracking. rxrpc: Fix loss of final ack on shutdown rxrpc: Fix bundle counting for exclusive connections netfilter: restore NF_INET_NUMHOOKS ibmveth: Identify ingress large send packets. ibmveth: Switch order of ibmveth_helper calls. cxgb4: handle 4-tuple PEDIT to NAT mode translation selftests: Add VRF route leaking tests ... |
|
|
Toke Høiland-Jørgensen
|
3aac1ead5e |
bpf: Move prog->aux->linked_prog and trampoline into bpf_link on attach
In preparation for allowing multiple attachments of freplace programs, move the references to the target program and trampoline into the bpf_tracing_link structure when that is created. To do this atomically, introduce a new mutex in prog->aux to protect writing to the two pointers to target prog and trampoline, and rename the members to make it clear that they are related. With this change, it is no longer possible to attach the same tracing program multiple times (detaching in-between), since the reference from the tracing program to the target disappears on the first attach. However, since the next patch will let the caller supply an attach target, that will also make it possible to attach to the same place multiple times. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/160138355059.48470.2503076992210324984.stgit@toke.dk |
|
Alan Maguire
|
eb411377ae |
bpf: Add bpf_seq_printf_btf helper
A helper is added to allow seq file writing of kernel data
structures using vmlinux BTF. Its signature is
long bpf_seq_printf_btf(struct seq_file *m, struct btf_ptr *ptr,
u32 btf_ptr_size, u64 flags);
Flags and struct btf_ptr definitions/use are identical to the
bpf_snprintf_btf helper, and the helper returns 0 on success
or a negative error value.
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-8-git-send-email-alan.maguire@oracle.com
|
|
|
Alan Maguire
|
c4d0bfb450 |
bpf: Add bpf_snprintf_btf helper
A helper is added to support tracing kernel type information in BPF
using the BPF Type Format (BTF). Its signature is
long bpf_snprintf_btf(char *str, u32 str_size, struct btf_ptr *ptr,
u32 btf_ptr_size, u64 flags);
struct btf_ptr * specifies
- a pointer to the data to be traced
- the BTF id of the type of data pointed to
- a flags field is provided for future use; these flags
are not to be confused with the BTF_F_* flags
below that control how the btf_ptr is displayed; the
flags member of the struct btf_ptr may be used to
disambiguate types in kernel versus module BTF, etc;
the main distinction is the flags relate to the type
and information needed in identifying it; not how it
is displayed.
For example a BPF program with a struct sk_buff *skb
could do the following:
static struct btf_ptr b = { };
b.ptr = skb;
b.type_id = __builtin_btf_type_id(struct sk_buff, 1);
bpf_snprintf_btf(str, sizeof(str), &b, sizeof(b), 0, 0);
Default output looks like this:
(struct sk_buff){
.transport_header = (__u16)65535,
.mac_header = (__u16)65535,
.end = (sk_buff_data_t)192,
.head = (unsigned char *)0x000000007524fd8b,
.data = (unsigned char *)0x000000007524fd8b,
.truesize = (unsigned int)768,
.users = (refcount_t){
.refs = (atomic_t){
.counter = (int)1,
},
},
}
Flags modifying display are as follows:
- BTF_F_COMPACT: no formatting around type information
- BTF_F_NONAME: no struct/union member names/types
- BTF_F_PTR_RAW: show raw (unobfuscated) pointer values;
equivalent to %px.
- BTF_F_ZERO: show zero-valued struct/union members;
they are not displayed by default
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-4-git-send-email-alan.maguire@oracle.com
|
|
Maciej Fijalkowski
|
ebf7d1f508 |
bpf, x64: rework pro/epilogue and tailcall handling in JIT
This commit serves two things:
1) it optimizes BPF prologue/epilogue generation
2) it makes possible to have tailcalls within BPF subprogram
Both points are related to each other since without 1), 2) could not be
achieved.
In [1], Alexei says:
"The prologue will look like:
nop5
xor eax,eax // two new bytes if bpf_tail_call() is used in this
// function
push rbp
mov rbp, rsp
sub rsp, rounded_stack_depth
push rax // zero init tail_call counter
variable number of push rbx,r13,r14,r15
Then bpf_tail_call will pop variable number rbx,..
and final 'pop rax'
Then 'add rsp, size_of_current_stack_frame'
jmp to next function and skip over 'nop5; xor eax,eax; push rpb; mov
rbp, rsp'
This way new function will set its own stack size and will init tail
call
counter with whatever value the parent had.
If next function doesn't use bpf_tail_call it won't have 'xor eax,eax'.
Instead it would need to have 'nop2' in there."
Implement that suggestion.
Since the layout of stack is changed, tail call counter handling can not
rely anymore on popping it to rbx just like it have been handled for
constant prologue case and later overwrite of rbx with actual value of
rbx pushed to stack. Therefore, let's use one of the register (%rcx) that
is considered to be volatile/caller-saved and pop the value of tail call
counter in there in the epilogue.
Drop the BUILD_BUG_ON in emit_prologue and in
emit_bpf_tail_call_indirect where instruction layout is not constant
anymore.
Introduce new poke target, 'tailcall_bypass' to poke descriptor that is
dedicated for skipping the register pops and stack unwind that are
generated right before the actual jump to target program.
For case when the target program is not present, BPF program will skip
the pop instructions and nop5 dedicated for jmpq $target. An example of
such state when only R6 of callee saved registers is used by program:
ffffffffc0513aa1: e9 0e 00 00 00 jmpq 0xffffffffc0513ab4
ffffffffc0513aa6: 5b pop %rbx
ffffffffc0513aa7: 58 pop %rax
ffffffffc0513aa8: 48 81 c4 00 00 00 00 add $0x0,%rsp
ffffffffc0513aaf: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
ffffffffc0513ab4: 48 89 df mov %rbx,%rdi
When target program is inserted, the jump that was there to skip
pops/nop5 will become the nop5, so CPU will go over pops and do the
actual tailcall.
One might ask why there simply can not be pushes after the nop5?
In the following example snippet:
ffffffffc037030c: 48 89 fb mov %rdi,%rbx
(...)
ffffffffc0370332: 5b pop %rbx
ffffffffc0370333: 58 pop %rax
ffffffffc0370334: 48 81 c4 00 00 00 00 add $0x0,%rsp
ffffffffc037033b: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1)
ffffffffc0370340: 48 81 ec 00 00 00 00 sub $0x0,%rsp
ffffffffc0370347: 50 push %rax
ffffffffc0370348: 53 push %rbx
ffffffffc0370349: 48 89 df mov %rbx,%rdi
ffffffffc037034c: e8 f7 21 00 00 callq 0xffffffffc0372548
There is the bpf2bpf call (at ffffffffc037034c) right after the tailcall
and jump target is not present. ctx is in %rbx register and BPF
subprogram that we will call into on ffffffffc037034c is relying on it,
e.g. it will pick ctx from there. Such code layout is therefore broken
as we would overwrite the content of %rbx with the value that was pushed
on the prologue. That is the reason for the 'bypass' approach.
Special care needs to be taken during the install/update/remove of
tailcall target. In case when target program is not present, the CPU
must not execute the pop instructions that precede the tailcall.
To address that, the following states can be defined:
A nop, unwind, nop
B nop, unwind, tail
C skip, unwind, nop
D skip, unwind, tail
A is forbidden (lead to incorrectness). The state transitions between
tailcall install/update/remove will work as follows:
First install tail call f: C->D->B(f)
* poke the tailcall, after that get rid of the skip
Update tail call f to f': B(f)->B(f')
* poke the tailcall (poke->tailcall_target) and do NOT touch the
poke->tailcall_bypass
Remove tail call: B(f')->C(f')
* poke->tailcall_bypass is poked back to jump, then we wait the RCU
grace period so that other programs will finish its execution and
after that we are safe to remove the poke->tailcall_target
Install new tail call (f''): C(f')->D(f'')->B(f'').
* same as first step
This way CPU can never be exposed to "unwind, tail" state.
Last but not least, when tailcalls get mixed with bpf2bpf calls, it
would be possible to encounter the endless loop due to clearing the
tailcall counter if for example we would use the tailcall3-like from BPF
selftests program that would be subprogram-based, meaning the tailcall
would be present within the BPF subprogram.
This test, broken down to particular steps, would do:
entry -> set tailcall counter to 0, bump it by 1, tailcall to func0
func0 -> call subprog_tail
(we are NOT skipping the first 11 bytes of prologue and this subprogram
has a tailcall, therefore we clear the counter...)
subprog -> do the same thing as entry
and then loop forever.
To address this, the idea is to go through the call chain of bpf2bpf progs
and look for a tailcall presence throughout whole chain. If we saw a single
tail call then each node in this call chain needs to be marked as a subprog
that can reach the tailcall. We would later feed the JIT with this info
and:
- set eax to 0 only when tailcall is reachable and this is the entry prog
- if tailcall is reachable but there's no tailcall in insns of currently
JITed prog then push rax anyway, so that it will be possible to
propagate further down the call chain
- finally if tailcall is reachable, then we need to precede the 'call'
insn with mov rax, [rbp - (stack_depth + 8)]
Tail call related cases from test_verifier kselftest are also working
fine. Sample BPF programs that utilize tail calls (sockex3, tracex5)
work properly as well.
[1]: https://lore.kernel.org/bpf/20200517043227.2gpq22ifoq37ogst@ast-mbp.dhcp.thefacebook.com/
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
|
Maciej Fijalkowski
|
cf71b174d3 |
bpf: rename poke descriptor's 'ip' member to 'tailcall_target'
Reflect the actual purpose of poke->ip and rename it to poke->tailcall_target so that it will not the be confused with another poke target that will be introduced in next commit. While at it, do the same thing with poke->ip_stable - rename it to poke->tailcall_target_stable. Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
YiFei Zhu
|
984fe94f94 |
bpf: Mutex protect used_maps array and count
To support modifying the used_maps array, we use a mutex to protect the use of the counter and the array. The mutex is initialized right after the prog aux is allocated, and destroyed right before prog aux is freed. This way we guarantee it's initialized for both cBPF and eBPF. Signed-off-by: YiFei Zhu <zhuyifei@google.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Cc: YiFei Zhu <zhuyifei1999@gmail.com> Link: https://lore.kernel.org/bpf/20200915234543.3220146-2-sdf@google.com |
|
Julien Thierry
|
00089c048e |
objtool: Rename frame.h -> objtool.h
Header frame.h is getting more code annotations to help objtool analyze object files. Rename the file to objtool.h. [ jpoimboe: add objtool.h to MAINTAINERS ] Signed-off-by: Julien Thierry <jthierry@redhat.com> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com> |
|
|
Randy Dunlap
|
b8c1a30907 |
bpf: Delete repeated words in comments
Drop repeated words in kernel/bpf/: {has, the}
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200807033141.10437-1-rdunlap@infradead.org
|
|
|
YiFei Zhu
|
7d9c342789 |
bpf: Make cgroup storages shared between programs on the same cgroup
This change comes in several parts:
One, the restriction that the CGROUP_STORAGE map can only be used
by one program is removed. This results in the removal of the field
'aux' in struct bpf_cgroup_storage_map, and removal of relevant
code associated with the field, and removal of now-noop functions
bpf_free_cgroup_storage and bpf_cgroup_storage_release.
Second, we permit a key of type u64 as the key to the map.
Providing such a key type indicates that the map should ignore
attach type when comparing map keys. However, for simplicity newly
linked storage will still have the attach type at link time in
its key struct. cgroup_storage_check_btf is adapted to accept
u64 as the type of the key.
Third, because the storages are now shared, the storages cannot
be unconditionally freed on program detach. There could be two
ways to solve this issue:
* A. Reference count the usage of the storages, and free when the
last program is detached.
* B. Free only when the storage is impossible to be referred to
again, i.e. when either the cgroup_bpf it is attached to, or
the map itself, is freed.
Option A has the side effect that, when the user detach and
reattach a program, whether the program gets a fresh storage
depends on whether there is another program attached using that
storage. This could trigger races if the user is multi-threaded,
and since nondeterminism in data races is evil, go with option B.
The both the map and the cgroup_bpf now tracks their associated
storages, and the storage unlink and free are removed from
cgroup_bpf_detach and added to cgroup_bpf_release and
cgroup_storage_map_free. The latter also new holds the cgroup_mutex
to prevent any races with the former.
Fourth, on attach, we reuse the old storage if the key already
exists in the map, via cgroup_storage_lookup. If the storage
does not exist yet, we create a new one, and publish it at the
last step in the attach process. This does not create a race
condition because for the whole attach the cgroup_mutex is held.
We keep track of an array of new storages that was allocated
and if the process fails only the new storages would get freed.
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/d5401c6106728a00890401190db40020a1f84ff1.1595565795.git.zhuyifei@google.com
|
|
Jakub Sitnicki
|
ce3aa9cc51 |
bpf, netns: Handle multiple link attachments
Extend the BPF netns link callbacks to rebuild (grow/shrink) or update the prog_array at given position when link gets attached/updated/released. This let's us lift the limit of having just one link attached for the new attach type introduced by subsequent patch. No functional changes intended. Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200717103536.397595-2-jakub@cloudflare.com |
|
|
Linus Torvalds
|
cb8e59cc87 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:
1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
Augusto von Dentz.
2) Add GSO partial support to igc, from Sasha Neftin.
3) Several cleanups and improvements to r8169 from Heiner Kallweit.
4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
device self-test. From Andrew Lunn.
5) Start moving away from custom driver versions, use the globally
defined kernel version instead, from Leon Romanovsky.
6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.
7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.
8) Add sriov and vf support to hinic, from Luo bin.
9) Support Media Redundancy Protocol (MRP) in the bridging code, from
Horatiu Vultur.
10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.
11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
Dubroca. Also add ipv6 support for espintcp.
12) Lots of ReST conversions of the networking documentation, from Mauro
Carvalho Chehab.
13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
from Doug Berger.
14) Allow to dump cgroup id and filter by it in inet_diag code, from
Dmitry Yakunin.
15) Add infrastructure to export netlink attribute policies to
userspace, from Johannes Berg.
16) Several optimizations to sch_fq scheduler, from Eric Dumazet.
17) Fallback to the default qdisc if qdisc init fails because otherwise
a packet scheduler init failure will make a device inoperative. From
Jesper Dangaard Brouer.
18) Several RISCV bpf jit optimizations, from Luke Nelson.
19) Correct the return type of the ->ndo_start_xmit() method in several
drivers, it's netdev_tx_t but many drivers were using
'int'. From Yunjian Wang.
20) Add an ethtool interface for PHY master/slave config, from Oleksij
Rempel.
21) Add BPF iterators, from Yonghang Song.
22) Add cable test infrastructure, including ethool interfaces, from
Andrew Lunn. Marvell PHY driver is the first to support this
facility.
23) Remove zero-length arrays all over, from Gustavo A. R. Silva.
24) Calculate and maintain an explicit frame size in XDP, from Jesper
Dangaard Brouer.
25) Add CAP_BPF, from Alexei Starovoitov.
26) Support terse dumps in the packet scheduler, from Vlad Buslov.
27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.
28) Add devm_register_netdev(), from Bartosz Golaszewski.
29) Minimize qdisc resets, from Cong Wang.
30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
eliminate set_fs/get_fs calls. From Christoph Hellwig.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
selftests: net: ip_defrag: ignore EPERM
net_failover: fixed rollback in net_failover_open()
Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
vmxnet3: allow rx flow hash ops only when rss is enabled
hinic: add set_channels ethtool_ops support
selftests/bpf: Add a default $(CXX) value
tools/bpf: Don't use $(COMPILE.c)
bpf, selftests: Use bpf_probe_read_kernel
s390/bpf: Use bcr 0,%0 as tail call nop filler
s390/bpf: Maintain 8-byte stack alignment
selftests/bpf: Fix verifier test
selftests/bpf: Fix sample_cnt shared between two threads
bpf, selftests: Adapt cls_redirect to call csum_level helper
bpf: Add csum_level helper for fixing up csum levels
bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
crypto/chtls: IPv6 support for inline TLS
Crypto/chcr: Fixes a coccinile check error
Crypto/chcr: Fixes compilations warnings
...
|
|
|
Christoph Hellwig
|
88dca4ca5a |
mm: remove the pgprot argument to __vmalloc
The pgprot argument to __vmalloc is always PAGE_KERNEL now, so remove it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Michael Kelley <mikelley@microsoft.com> [hyperv] Acked-by: Gao Xiang <xiang@kernel.org> [erofs] Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Wei Liu <wei.liu@kernel.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Christophe Leroy <christophe.leroy@c-s.fr> Cc: Daniel Vetter <daniel.vetter@ffwll.ch> Cc: David Airlie <airlied@linux.ie> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Haiyang Zhang <haiyangz@microsoft.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: "K. Y. Srinivasan" <kys@microsoft.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Minchan Kim <minchan@kernel.org> Cc: Nitin Gupta <ngupta@vflare.org> Cc: Robin Murphy <robin.murphy@arm.com> Cc: Sakari Ailus <sakari.ailus@linux.intel.com> Cc: Stephen Hemminger <sthemmin@microsoft.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Paul Mackerras <paulus@ozlabs.org> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Will Deacon <will@kernel.org> Link: http://lkml.kernel.org/r/20200414131348.444715-22-hch@lst.de Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
|
Chris Packham
|
0142dddcbe |
bpf: Fix spelling in comment explaining ARG1 in ___bpf_prog_run
Change 'handeled' to 'handled'. Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200525230025.14470-1-chris.packham@alliedtelesis.co.nz Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Alexei Starovoitov
|
2c78ee898d |
bpf: Implement CAP_BPF
Implement permissions as stated in uapi/linux/capability.h In order to do that the verifier allow_ptr_leaks flag is split into four flags and they are set as: env->allow_ptr_leaks = bpf_allow_ptr_leaks(); env->bypass_spec_v1 = bpf_bypass_spec_v1(); env->bypass_spec_v4 = bpf_bypass_spec_v4(); env->bpf_capable = bpf_capable(); The first three currently equivalent to perfmon_capable(), since leaking kernel pointers and reading kernel memory via side channel attacks is roughly equivalent to reading kernel memory with cap_perfmon. 'bpf_capable' enables bounded loops, precision tracking, bpf to bpf calls and other verifier features. 'allow_ptr_leaks' enable ptr leaks, ptr conversions, subtraction of pointers. 'bypass_spec_v1' disables speculative analysis in the verifier, run time mitigations in bpf array, and enables indirect variable access in bpf programs. 'bypass_spec_v4' disables emission of sanitation code by the verifier. That means that the networking BPF program loaded with CAP_BPF + CAP_NET_ADMIN will have speculative checks done by the verifier and other spectre mitigation applied. Such networking BPF program will not be able to leak kernel pointers and will not be able to access arbitrary kernel memory. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200513230355.7858-3-alexei.starovoitov@gmail.com |
|
Eric Biggers
|
6b0b0fa2bc |
crypto: lib/sha1 - rename "sha" to "sha1"
The library implementation of the SHA-1 compression function is confusingly called just "sha_transform()". Alongside it are some "SHA_" constants and "sha_init()". Presumably these are left over from a time when SHA just meant SHA-1. But now there are also SHA-2 and SHA-3, and moreover SHA-1 is now considered insecure and thus shouldn't be used. Therefore, rename these functions and constants to make it very clear that they are for SHA-1. Also add a comment to make it clear that these shouldn't be used. For the extra-misleadingly named "SHA_MESSAGE_BYTES", rename it to SHA1_BLOCK_SIZE and define it to just '64' rather than '(512/8)' so that it matches the same definition in <crypto/sha.h>. This prepares for merging <linux/cryptohash.h> into <crypto/sha.h>. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> |
|
Maciej Żenczykowski
|
71d1921477 |
bpf: add bpf_ktime_get_boot_ns()
On a device like a cellphone which is constantly suspending and resuming CLOCK_MONOTONIC is not particularly useful for keeping track of or reacting to external network events. Instead you want to use CLOCK_BOOTTIME. Hence add bpf_ktime_get_boot_ns() as a mirror of bpf_ktime_get_ns() based around CLOCK_BOOTTIME instead of CLOCK_MONOTONIC. Signed-off-by: Maciej Żenczykowski <maze@google.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Stanislav Fomichev
|
6890896bd7 |
bpf: Fix missing bpf_base_func_proto in cgroup_base_func_proto for CGROUP_NET=n
linux-next build bot reported compile issue [1] with one of its
configs. It looks like when we have CONFIG_NET=n and
CONFIG_BPF{,_SYSCALL}=y, we are missing the bpf_base_func_proto
definition (from net/core/filter.c) in cgroup_base_func_proto.
I'm reshuffling the code a bit to make it work. The common helpers
are moved into kernel/bpf/helpers.c and the bpf_base_func_proto is
exported from there.
Also, bpf_get_raw_cpu_id goes into kernel/bpf/core.c akin to existing
bpf_user_rnd_u32.
[1] https://lore.kernel.org/linux-next/CAKH8qBsBvKHswiX1nx40LgO+BGeTmb1NX8tiTttt_0uu6T3dCA@mail.gmail.com/T/#mff8b0c083314c68c2e2ef0211cb11bc20dc13c72
Fixes:
|
|
|
Daniel Borkmann
|
0f09abd105 |
bpf: Enable bpf cgroup hooks to retrieve cgroup v2 and ancestor id
Enable the bpf_get_current_cgroup_id() helper for connect(), sendmsg(),
recvmsg() and bind-related hooks in order to retrieve the cgroup v2
context which can then be used as part of the key for BPF map lookups,
for example. Given these hooks operate in process context 'current' is
always valid and pointing to the app that is performing mentioned
syscalls if it's subject to a v2 cgroup. Also with same motivation of
commit
|
|
Jiri Olsa
|
dba122fb5e |
bpf: Add bpf_ksym_add/del functions
Separating /proc/kallsyms add/del code and adding bpf_ksym_add/del functions for that. Moving bpf_prog_ksym_node_add/del functions to __bpf_ksym_add/del and changing their argument to 'struct bpf_ksym' object. This way we can call them for other bpf objects types like trampoline and dispatcher. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200312195610.346362-10-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jiri Olsa
|
cbd76f8d5a |
bpf: Add prog flag to struct bpf_ksym object
Adding 'prog' bool flag to 'struct bpf_ksym' to mark that this object belongs to bpf_prog object. This change allows having bpf_prog objects together with other types (trampolines and dispatchers) in the single bpf_tree. It's used when searching for bpf_prog exception tables by the bpf_prog_ksym_find function, where we need to get the bpf_prog pointer. >From now we can safely add bpf_ksym support for trampoline or dispatcher objects, because we can differentiate them from bpf_prog objects. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200312195610.346362-9-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jiri Olsa
|
eda0c92902 |
bpf: Add bpf_ksym_find function
Adding bpf_ksym_find function that is used bpf bpf address lookup functions: __bpf_address_lookup is_bpf_text_address while keeping bpf_prog_kallsyms_find to be used only for lookup of bpf_prog objects (will happen in following changes). Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200312195610.346362-8-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jiri Olsa
|
ca4424c920 |
bpf: Move ksym_tnode to bpf_ksym
Moving ksym_tnode list node to 'struct bpf_ksym' object, so the symbol itself can be chained and used in other objects like bpf_trampoline and bpf_dispatcher. We need bpf_ksym object to be linked both in bpf_kallsyms via lnode for /proc/kallsyms and in bpf_tree via tnode for bpf address lookup functions like __bpf_address_lookup or bpf_prog_kallsyms_find. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200312195610.346362-7-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jiri Olsa
|
ecb60d1c67 |
bpf: Move lnode list node to struct bpf_ksym
Adding lnode list node to 'struct bpf_ksym' object, so the struct bpf_ksym itself can be chained and used in other objects like bpf_trampoline and bpf_dispatcher. Changing iterator to bpf_ksym in bpf_get_kallsym function. The ksym->start is holding the prog->bpf_func value, so it's ok to use it as value in bpf_get_kallsym. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200312195610.346362-6-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jiri Olsa
|
bfea9a8574 |
bpf: Add name to struct bpf_ksym
Adding name to 'struct bpf_ksym' object to carry the name of the symbol for bpf_prog, bpf_trampoline, bpf_dispatcher objects. The current benefit is that name is now generated only when the symbol is added to the list, so we don't need to generate it every time it's accessed. The future benefit is that we will have all the bpf objects symbols represented by struct bpf_ksym. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200312195610.346362-5-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Jiri Olsa
|
535911c80a |
bpf: Add struct bpf_ksym
Adding 'struct bpf_ksym' object that will carry the kallsym information for bpf symbol. Adding the start and end address to begin with. It will be used by bpf_prog, bpf_trampoline, bpf_dispatcher objects. The symbol_start/symbol_end values were originally used to sort bpf_prog objects. For the address displayed in /proc/kallsyms we are using prog->bpf_func value. I'm using the bpf_func value for program symbol start instead of the symbol_start, because it makes no difference for sorting bpf_prog objects and we can use it directly as an address to display it in /proc/kallsyms. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200312195610.346362-4-jolsa@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
Carlos Neira
|
b4490c5c4e |
bpf: Added new helper bpf_get_ns_current_pid_tgid
New bpf helper bpf_get_ns_current_pid_tgid, This helper will return pid and tgid from current task which namespace matches dev_t and inode number provided, this will allows us to instrument a process inside a container. Signed-off-by: Carlos Neira <cneirabustos@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20200304204157.58695-3-cneirabustos@gmail.com |
|
|
Martin KaFai Lau
|
5576b991e9 |
bpf: Add BPF_FUNC_jiffies64
This patch adds a helper to read the 64bit jiffies. It will be used in a later patch to implement the bpf_cubic.c. The helper is inlined for jit_requested and 64 BITS_PER_LONG as the map_gen_lookup(). Other cases could be considered together with map_gen_lookup() if needed. Signed-off-by: Martin KaFai Lau <kafai@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200122233646.903260-1-kafai@fb.com |
|
David S. Miller
|
2bbc078f81 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says: ==================== pull-request: bpf-next 2019-12-27 The following pull-request contains BPF updates for your *net-next* tree. We've added 127 non-merge commits during the last 17 day(s) which contain a total of 110 files changed, 6901 insertions(+), 2721 deletions(-). There are three merge conflicts. Conflicts and resolution looks as follows: 1) Merge conflict in net/bpf/test_run.c: There was a tree-wide cleanup |
|
Aditya Pakki
|
5bf2fc1f9c |
bpf: Remove unnecessary assertion on fp_old
The two callers of bpf_prog_realloc - bpf_patch_insn_single and bpf_migrate_filter dereference the struct fp_old, before passing it to the function. Thus assertion to check fp_old is unnecessary and can be removed. Signed-off-by: Aditya Pakki <pakki001@umn.edu> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191219175735.19231-1-pakki001@umn.edu |
|
|
Daniel Borkmann
|
e47304232b |
bpf: Fix cgroup local storage prog tracking
Recently noticed that we're tracking programs related to local storage maps
through their prog pointer. This is a wrong assumption since the prog pointer
can still change throughout the verification process, for example, whenever
bpf_patch_insn_single() is called.
Therefore, the prog pointer that was assigned via bpf_cgroup_storage_assign()
is not guaranteed to be the same as we pass in bpf_cgroup_storage_release()
and the map would therefore remain in busy state forever. Fix this by using
the prog's aux pointer which is stable throughout verification and beyond.
Fixes:
|
|
|
Daniel Borkmann
|
a2ea07465c |
bpf: Fix missing prog untrack in release_maps
Commit |
|
|
Daniel Borkmann
|
81c22041d9 |
bpf, x86, arm64: Enable jit by default when not built as always-on
After Spectre 2 fix via |
|
|
Daniel Borkmann
|
da765a2f59 |
bpf: Add poke dependency tracking for prog array maps
This work adds program tracking to prog array maps. This is needed such
that upon prog array updates/deletions we can fix up all programs which
make use of this tail call map. We add ops->map_poke_{un,}track()
helpers to maps to maintain the list of programs and ops->map_poke_run()
for triggering the actual update.
bpf_array_aux is extended to contain the list head and poke_mutex in
order to serialize program patching during updates/deletions.
bpf_free_used_maps() will untrack the program shortly before dropping
the reference to the map. For clearing out the prog array once all urefs
are dropped we need to use schedule_work() to have a sleepable context.
The prog_array_map_poke_run() is triggered during updates/deletions and
walks the maintained prog list. It checks in their poke_tabs whether the
map and key is matching and runs the actual bpf_arch_text_poke() for
patching in the nop or new jmp location. Depending on the type of update,
we use one of BPF_MOD_{NOP_TO_JUMP,JUMP_TO_NOP,JUMP_TO_JUMP}.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/1fb364bb3c565b3e415d5ea348f036ff379e779d.1574452833.git.daniel@iogearbox.net
|
|
|
Daniel Borkmann
|
a66886fe6c |
bpf: Add initial poke descriptor table for jit images
Add initial poke table data structures and management to the BPF prog that can later be used by JITs. Also add an instance of poke specific data for tail call maps; plan for later work is to extend this also for BPF static keys. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/1db285ec2ea4207ee0455b3f8e191a4fc58b9ade.1574452833.git.daniel@iogearbox.net |
|
|
Daniel Borkmann
|
2beee5f574 |
bpf: Move owner type, jited info into array auxiliary data
We're going to extend this with further information which is only relevant for prog array at this point. Given this info is not used in critical path, move it into its own structure such that the main array map structure can be kept on diet. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/b9ddccdb0f6f7026489ee955f16c96381e1e7238.1574452833.git.daniel@iogearbox.net |
|
|
Daniel Borkmann
|
6332be04c0 |
bpf: Move bpf_free_used_maps into sleepable section
We later on are going to need a sleepable context as opposed to plain RCU callback in order to untrack programs we need to poke at runtime and tracking as well as image update is performed under mutex. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/09823b1d5262876e9b83a8e75df04cf0467357a4.1574452833.git.daniel@iogearbox.net |
|
|
Alexei Starovoitov
|
5b92a28aae |
bpf: Support attaching tracing BPF program to other BPF programs
Allow FENTRY/FEXIT BPF programs to attach to other BPF programs of any type including their subprograms. This feature allows snooping on input and output packets in XDP, TC programs including their return values. In order to do that the verifier needs to track types not only of vmlinux, but types of other BPF programs as well. The verifier also needs to translate uapi/linux/bpf.h types used by networking programs into kernel internal BTF types used by FENTRY/FEXIT BPF programs. In some cases LLVM optimizations can remove arguments from BPF subprograms without adjusting BTF info that LLVM backend knows. When BTF info disagrees with actual types that the verifiers sees the BPF trampoline has to fallback to conservative and treat all arguments as u64. The FENTRY/FEXIT program can still attach to such subprograms, but it won't be able to recognize pointer types like 'struct sk_buff *' and it won't be able to pass them to bpf_skb_output() for dumping packets to user space. The FENTRY/FEXIT program would need to use bpf_probe_read_kernel() instead. The BPF_PROG_LOAD command is extended with attach_prog_fd field. When it's set to zero the attach_btf_id is one vmlinux BTF type ids. When attach_prog_fd points to previously loaded BPF program the attach_btf_id is BTF type id of main function or one of its subprograms. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20191114185720.1641606-18-ast@kernel.org |
|
|
Alexei Starovoitov
|
fec56f5890 |
bpf: Introduce BPF trampoline
Introduce BPF trampoline concept to allow kernel code to call into BPF programs with practically zero overhead. The trampoline generation logic is architecture dependent. It's converting native calling convention into BPF calling convention. BPF ISA is 64-bit (even on 32-bit architectures). The registers R1 to R5 are used to pass arguments into BPF functions. The main BPF program accepts only single argument "ctx" in R1. Whereas CPU native calling convention is different. x86-64 is passing first 6 arguments in registers and the rest on the stack. x86-32 is passing first 3 arguments in registers. sparc64 is passing first 6 in registers. And so on. The trampolines between BPF and kernel already exist. BPF_CALL_x macros in include/linux/filter.h statically compile trampolines from BPF into kernel helpers. They convert up to five u64 arguments into kernel C pointers and integers. On 64-bit architectures this BPF_to_kernel trampolines are nops. On 32-bit architecture they're meaningful. The opposite job kernel_to_BPF trampolines is done by CAST_TO_U64 macros and __bpf_trace_##call() shim functions in include/trace/bpf_probe.h. They convert kernel function arguments into array of u64s that BPF program consumes via R1=ctx pointer. This patch set is doing the same job as __bpf_trace_##call() static trampolines, but dynamically for any kernel function. There are ~22k global kernel functions that are attachable via nop at function entry. The function arguments and types are described in BTF. The job of btf_distill_func_proto() function is to extract useful information from BTF into "function model" that architecture dependent trampoline generators will use to generate assembly code to cast kernel function arguments into array of u64s. For example the kernel function eth_type_trans has two pointers. They will be casted to u64 and stored into stack of generated trampoline. The pointer to that stack space will be passed into BPF program in R1. On x86-64 such generated trampoline will consume 16 bytes of stack and two stores of %rdi and %rsi into stack. The verifier will make sure that only two u64 are accessed read-only by BPF program. The verifier will also recognize the precise type of the pointers being accessed and will not allow typecasting of the pointer to a different type within BPF program. The tracing use case in the datacenter demonstrated that certain key kernel functions have (like tcp_retransmit_skb) have 2 or more kprobes that are always active. Other functions have both kprobe and kretprobe. So it is essential to keep both kernel code and BPF programs executing at maximum speed. Hence generated BPF trampoline is re-generated every time new program is attached or detached to maintain maximum performance. To avoid the high cost of retpoline the attached BPF programs are called directly. __bpf_prog_enter/exit() are used to support per-program execution stats. In the future this logic will be optimized further by adding support for bpf_stats_enabled_key inside generated assembly code. Introduction of preemptible and sleepable BPF programs will completely remove the need to call to __bpf_prog_enter/exit(). Detach of a BPF program from the trampoline should not fail. To avoid memory allocation in detach path the half of the page is used as a reserve and flipped after each attach/detach. 2k bytes is enough to call 40+ BPF programs directly which is enough for BPF tracing use cases. This limit can be increased in the future. BPF_TRACE_FENTRY programs have access to raw kernel function arguments while BPF_TRACE_FEXIT programs have access to kernel return value as well. Often kprobe BPF program remembers function arguments in a map while kretprobe fetches arguments from a map and analyzes them together with return value. BPF_TRACE_FEXIT accelerates this typical use case. Recursion prevention for kprobe BPF programs is done via per-cpu bpf_prog_active counter. In practice that turned out to be a mistake. It caused programs to randomly skip execution. The tracing tools missed results they were looking for. Hence BPF trampoline doesn't provide builtin recursion prevention. It's a job of BPF program itself and will be addressed in the follow up patches. BPF trampoline is intended to be used beyond tracing and fentry/fexit use cases in the future. For example to remove retpoline cost from XDP programs. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20191114185720.1641606-5-ast@kernel.org |
|
|
Alexei Starovoitov
|
5964b2000f |
bpf: Add bpf_arch_text_poke() helper
Add bpf_arch_text_poke() helper that is used by BPF trampoline logic to patch nops/calls in kernel text into calls into BPF trampoline and to patch calls/nops inside BPF programs too. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20191114185720.1641606-4-ast@kernel.org |
|
Ilya Leoshkevich
|
b7b3fc8dd9 |
bpf: Support doubleword alignment in bpf_jit_binary_alloc
Currently passing alignment greater than 4 to bpf_jit_binary_alloc does not work: in such cases it silently aligns only to 4 bytes. On s390, in order to load a constant from memory in a large (>512k) BPF program, one must use lgrl instruction, whose memory operand must be aligned on an 8-byte boundary. This patch makes it possible to request 8-byte alignment from bpf_jit_binary_alloc, and also makes it issue a warning when an unsupported alignment is requested. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191115123722.58462-1-iii@linux.ibm.com |
|
|
Martin KaFai Lau
|
85d31dd070 |
bpf: Account for insn->off when doing bpf_probe_read_kernel
In the bpf interpreter mode, bpf_probe_read_kernel is used to read
from PTR_TO_BTF_ID's kernel object. It currently missed considering
the insn->off. This patch fixes it.
Fixes:
|
|
|
David S. Miller
|
ae8a76fb8b |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Alexei Starovoitov says: ==================== pull-request: bpf-next 2019-11-02 The following pull-request contains BPF updates for your *net-next* tree. We've added 30 non-merge commits during the last 7 day(s) which contain a total of 41 files changed, 1864 insertions(+), 474 deletions(-). The main changes are: 1) Fix long standing user vs kernel access issue by introducing bpf_probe_read_user() and bpf_probe_read_kernel() helpers, from Daniel. 2) Accelerated xskmap lookup, from Björn and Maciej. 3) Support for automatic map pinning in libbpf, from Toke. 4) Cleanup of BTF-enabled raw tracepoints, from Alexei. 5) Various fixes to libbpf and selftests. ==================== Signed-off-by: David S. Miller <davem@davemloft.net> |
|
|
David S. Miller
|
d31e95585c |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
The only slightly tricky merge conflict was the netdevsim because the mutex locking fix overlapped a lot of driver reload reorganization. The rest were (relatively) trivial in nature. Signed-off-by: David S. Miller <davem@davemloft.net> |
|
|
Daniel Borkmann
|
6e07a63412 |
bpf: Switch BPF probe insns to bpf_probe_read_kernel
Commit
|
|
|
Alexei Starovoitov
|
af91acbc62 |
bpf: Fix bpf jit kallsym access
Jiri reported crash when JIT is on, but net.core.bpf_jit_kallsyms is off.
bpf_prog_kallsyms_find() was skipping addr->bpf_prog resolution
logic in oops and stack traces. That's incorrect.
It should only skip addr->name resolution for 'cat /proc/kallsyms'.
That's what bpf_jit_kallsyms and bpf_jit_harden protect.
Fixes:
|
|
|
Daniel Borkmann
|
cd7455f101 |
bpf: Fix use after free in subprog's jited symbol removal
syzkaller managed to trigger the following crash: [...] BUG: unable to handle page fault for address: ffffc90001923030 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD |
|
|
Alexei Starovoitov
|
3dec541b2e |
bpf: Add support for BTF pointers to x86 JIT
Pointer to BTF object is a pointer to kernel object or NULL. Such pointers can only be used by BPF_LDX instructions. The verifier changed their opcode from LDX|MEM|size to LDX|PROBE_MEM|size to make JITing easier. The number of entries in extable is the number of BPF_LDX insns that access kernel memory via "pointer to BTF type". Only these load instructions can fault. Since x86 extable is relative it has to be allocated in the same memory region as JITed code. Allocate it prior to last pass of JITing and let the last pass populate it. Pointer to extable in bpf_prog_aux is necessary to make page fault handling fast. Page fault handling is done in two steps: 1. bpf_prog_kallsyms_find() finds BPF program that page faulted. It's done by walking rb tree. 2. then extable for given bpf program is binary searched. This process is similar to how page faulting is done for kernel modules. The exception handler skips over faulting x86 instruction and initializes destination register with zero. This mimics exact behavior of bpf_probe_read (when probe_kernel_read faults dest is zeroed). JITs for other architectures can add support in similar way. Until then they will reject unknown opcode and fallback to interpreter. Since extable should be aligned and placed near JITed code make bpf_jit_binary_alloc() return 4 byte aligned image offset, so that extable aligning formula in bpf_int_jit_compile() doesn't need to rely on internal implementation of bpf_jit_binary_alloc(). On x86 gcc defaults to 16-byte alignment for regular kernel functions due to better performance. JITed code may be aligned to 16 in the future, but it will use 4 in the meantime. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20191016032505.2089704-10-ast@kernel.org |
|
|
Alexei Starovoitov
|
2a02759ef5 |
bpf: Add support for BTF pointers to interpreter
Pointer to BTF object is a pointer to kernel object or NULL. The memory access in the interpreter has to be done via probe_kernel_read to avoid page faults. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20191016032505.2089704-9-ast@kernel.org |
|
Naveen N. Rao
|
ede7c460b1 |
bpf: handle 32-bit zext during constant blinding
Since BPF constant blinding is performed after the verifier pass, the
ALU32 instructions inserted for doubleword immediate loads don't have a
corresponding zext instruction. This is causing a kernel oops on powerpc
and can be reproduced by running 'test_cgroup_storage' with
bpf_jit_harden=2.
Fix this by emitting BPF_ZEXT during constant blinding if
prog->aux->verifier_zext is set.
Fixes:
|
|
Josh Poimboeuf
|
3193c0836f |
bpf: Disable GCC -fgcse optimization for ___bpf_prog_run()
On x86-64, with CONFIG_RETPOLINE=n, GCC's "global common subexpression
elimination" optimization results in ___bpf_prog_run()'s jumptable code
changing from this:
select_insn:
jmp *jumptable(, %rax, 8)
...
ALU64_ADD_X:
...
jmp *jumptable(, %rax, 8)
ALU_ADD_X:
...
jmp *jumptable(, %rax, 8)
to this:
select_insn:
mov jumptable, %r12
jmp *(%r12, %rax, 8)
...
ALU64_ADD_X:
...
jmp *(%r12, %rax, 8)
ALU_ADD_X:
...
jmp *(%r12, %rax, 8)
The jumptable address is placed in a register once, at the beginning of
the function. The function execution can then go through multiple
indirect jumps which rely on that same register value. This has a few
issues:
1) Objtool isn't smart enough to be able to track such a register value
across multiple recursive indirect jumps through the jump table.
2) With CONFIG_RETPOLINE enabled, this optimization actually results in
a small slowdown. I measured a ~4.7% slowdown in the test_bpf
"tcpdump port 22" selftest.
This slowdown is actually predicted by the GCC manual:
Note: When compiling a program using computed gotos, a GCC
extension, you may get better run-time performance if you
disable the global common subexpression elimination pass by
adding -fno-gcse to the command line.
So just disable the optimization for this function.
Fixes:
|
|
Thomas Gleixner
|
54f698f31e |
Merge branch 'x86/debug' into core/urgent
Pick up the two pending objtool patches as the next round of objtool fixes depend on them. |
|
|
Josh Poimboeuf
|
e55a73251d |
bpf: Fix ORC unwinding in non-JIT BPF code
Objtool previously ignored ___bpf_prog_run() because it didn't understand
the jump table. This resulted in the ORC unwinder not being able to unwind
through non-JIT BPF code.
Now that objtool knows how to read jump tables, remove the whitelist and
annotate the jump table so objtool can recognize it.
Also add an additional "const" to the jump table definition to clarify that
the text pointers are constant. Otherwise GCC sets the section writable
flag and the assembler spits out warnings.
Fixes:
|
|
|
David S. Miller
|
af144a9834 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Two cases of overlapping changes, nothing fancy. Signed-off-by: David S. Miller <davem@davemloft.net> |
|
|
Stanislav Fomichev
|
0d01da6afc |
bpf: implement getsockopt and setsockopt hooks
Implement new BPF_PROG_TYPE_CGROUP_SOCKOPT program type and
BPF_CGROUP_{G,S}ETSOCKOPT cgroup hooks.
BPF_CGROUP_SETSOCKOPT can modify user setsockopt arguments before
passing them down to the kernel or bypass kernel completely.
BPF_CGROUP_GETSOCKOPT can can inspect/modify getsockopt arguments that
kernel returns.
Both hooks reuse existing PTR_TO_PACKET{,_END} infrastructure.
The buffer memory is pre-allocated (because I don't think there is
a precedent for working with __user memory from bpf). This might be
slow to do for each {s,g}etsockopt call, that's why I've added
__cgroup_bpf_prog_array_is_empty that exits early if there is nothing
attached to a cgroup. Note, however, that there is a race between
__cgroup_bpf_prog_array_is_empty and BPF_PROG_RUN_ARRAY where cgroup
program layout might have changed; this should not be a problem
because in general there is a race between multiple calls to
{s,g}etsocktop and user adding/removing bpf progs from a cgroup.
The return code of the BPF program is handled as follows:
* 0: EPERM
* 1: success, continue with next BPF program in the cgroup chain
v9:
* allow overwriting setsockopt arguments (Alexei Starovoitov):
* use set_fs (same as kernel_setsockopt)
* buffer is always kzalloc'd (no small on-stack buffer)
v8:
* use s32 for optlen (Andrii Nakryiko)
v7:
* return only 0 or 1 (Alexei Starovoitov)
* always run all progs (Alexei Starovoitov)
* use optval=0 as kernel bypass in setsockopt (Alexei Starovoitov)
(decided to use optval=-1 instead, optval=0 might be a valid input)
* call getsockopt hook after kernel handlers (Alexei Starovoitov)
v6:
* rework cgroup chaining; stop as soon as bpf program returns
0 or 2; see patch with the documentation for the details
* drop Andrii's and Martin's Acked-by (not sure they are comfortable
with the new state of things)
v5:
* skip copy_to_user() and put_user() when ret == 0 (Martin Lau)
v4:
* don't export bpf_sk_fullsock helper (Martin Lau)
* size != sizeof(__u64) for uapi pointers (Martin Lau)
* offsetof instead of bpf_ctx_range when checking ctx access (Martin Lau)
v3:
* typos in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY comments (Andrii Nakryiko)
* reverse christmas tree in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY (Andrii
Nakryiko)
* use __bpf_md_ptr instead of __u32 for optval{,_end} (Martin Lau)
* use BPF_FIELD_SIZEOF() for consistency (Martin Lau)
* new CG_SOCKOPT_ACCESS macro to wrap repeated parts
v2:
* moved bpf_sockopt_kern fields around to remove a hole (Martin Lau)
* aligned bpf_sockopt_kern->buf to 8 bytes (Martin Lau)
* bpf_prog_array_is_empty instead of bpf_prog_array_length (Martin Lau)
* added [0,2] return code check to verifier (Martin Lau)
* dropped unused buf[64] from the stack (Martin Lau)
* use PTR_TO_SOCKET for bpf_sockopt->sk (Martin Lau)
* dropped bpf_target_off from ctx rewrites (Martin Lau)
* use return code for kernel bypass (Martin Lau & Andrii Nakryiko)
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
|
Jiong Wang
|
75672dda27 |
bpf: fix BPF_ALU32 | BPF_ARSH on BE arches
Yauheni reported the following code do not work correctly on BE arches:
ALU_ARSH_X:
DST = (u64) (u32) ((*(s32 *) &DST) >> SRC);
CONT;
ALU_ARSH_K:
DST = (u64) (u32) ((*(s32 *) &DST) >> IMM);
CONT;
and are causing failure of test_verifier test 'arsh32 on imm 2' on BE
arches.
The code is taking address and interpreting memory directly, so is not
endianness neutral. We should instead perform standard C type casting on
the variable. A u64 to s32 conversion will drop the high 32-bit and reserve
the low 32-bit as signed integer, this is all we want.
Fixes:
|
|
Toshiaki Makita
|
e7d4798960 |
xdp: Add tracepoint for bulk XDP_TX
This is introduced for admins to check what is happening on XDP_TX when bulk XDP_TX is in use, which will be first introduced in veth in next commit. v3: - Add act field to be in line with other XDP tracepoints. Signed-off-by: Toshiaki Makita <toshiaki.makita1@gmail.com> Acked-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> |
|
|
David S. Miller
|
13091aa305 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Honestly all the conflicts were simple overlapping changes, nothing really interesting to report. Signed-off-by: David S. Miller <davem@davemloft.net> |
|
|
Eric Dumazet
|
a8e11e5c56 |
sysctl: define proc_do_static_key()
Convert proc_dointvec_minmax_bpf_stats() into a more generic helper, since we are going to use jump labels more often. Note that sysctl_bpf_stats_enabled is removed, since it is no longer needed/used. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net> |
|
|
David S. Miller
|
a6cdeeb16b |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Some ISDN files that got removed in net-next had some changes done in mainline, take the removals. Signed-off-by: David S. Miller <davem@davemloft.net> |
|
|
Thomas Gleixner
|
2874c5fd28 |
treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
|
|
Stanislav Fomichev
|
54e9c9d4b5 |
bpf: remove __rcu annotations from bpf_prog_array
Drop __rcu annotations and rcu read sections from bpf_prog_array helper functions. They are not needed since all existing callers call those helpers from the rcu update side while holding a mutex. This guarantees that use-after-free could not happen. In the next patches I'll fix the callers with missing rcu_dereference_protected to make sparse/lockdep happy, the proper way to use these helpers is: struct bpf_prog_array __rcu *progs = ...; struct bpf_prog_array *p; mutex_lock(&mtx); p = rcu_dereference_protected(progs, lockdep_is_held(&mtx)); bpf_prog_array_length(p); bpf_prog_array_copy_to_user(p, ...); bpf_prog_array_delete_safe(p, ...); bpf_prog_array_copy_info(p, ...); bpf_prog_array_copy(p, ...); bpf_prog_array_free(p); mutex_unlock(&mtx); No functional changes! rcu_dereference_protected with lockdep_is_held should catch any cases where we update prog array without a mutex (I've looked at existing call sites and I think we hold a mutex everywhere). Motivation is to fix sparse warnings: kernel/bpf/core.c:1803:9: warning: incorrect type in argument 1 (different address spaces) kernel/bpf/core.c:1803:9: expected struct callback_head *head kernel/bpf/core.c:1803:9: got struct callback_head [noderef] <asn:4> * kernel/bpf/core.c:1877:44: warning: incorrect type in initializer (different address spaces) kernel/bpf/core.c:1877:44: expected struct bpf_prog_array_item *item kernel/bpf/core.c:1877:44: got struct bpf_prog_array_item [noderef] <asn:4> * kernel/bpf/core.c:1901:26: warning: incorrect type in assignment (different address spaces) kernel/bpf/core.c:1901:26: expected struct bpf_prog_array_item *existing kernel/bpf/core.c:1901:26: got struct bpf_prog_array_item [noderef] <asn:4> * kernel/bpf/core.c:1935:26: warning: incorrect type in assignment (different address spaces) kernel/bpf/core.c:1935:26: expected struct bpf_prog_array_item *[assigned] existing kernel/bpf/core.c:1935:26: got struct bpf_prog_array_item [noderef] <asn:4> * v2: * remove comment about potential race; that can't happen because all callers are in rcu-update section Cc: Roman Gushchin <guro@fb.com> Acked-by: Roman Gushchin <guro@fb.com> Signed-off-by: Stanislav Fomichev <sdf@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> |
|
|
Jiong Wang
|
a4b1d3c1dd |
bpf: verifier: insert zero extension according to analysis result
After previous patches, verifier will mark a insn if it really needs zero extension on dst_reg. It is then for back-ends to decide how to use such information to eliminate unnecessary zero extension code-gen during JIT compilation. One approach is verifier insert explicit zero extension for those insns that need zero extension in a generic way, JIT back-ends then do not generate zero extension for sub-register write at default. However, only those back-ends which do not have hardware zero extension want this optimization. Back-ends like x86_64 and AArch64 have hardware zero extension support that the insertion should be disabled. This patch introduces new target hook "bpf_jit_needs_zext" which returns false at default, meaning verifier zero extension insertion is disabled at default. A back-end could override this hook to return true if it doesn't have hardware support and want verifier insert zero extension explicitly. Offload targets do not use this native target hook, instead, they could get the optimization results using bpf_prog_offload_ops.finalize. NOTE: arches could have diversified features, it is possible for one arch to have hardware zero extension support for some sub-register write insns but not for all. For example, PowerPC, SPARC have zero extended loads, but not for alu32. So when verifier zero extension insertion enabled, these JIT back-ends need to peephole insns to remove those zero extension inserted for insn that actually has hardware zero extension support. The peephole could be as simple as looking the next insn, if it is a special zero extension insn then it is safe to eliminate it if the current insn has hardware zero extension support. Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: Jiong Wang <jiong.wang@netronome.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
|
|
Daniel Borkmann
|
af959b18fd |
bpf: fix out of bounds backwards jmps due to dead code removal
systemtap folks reported the following splat recently: [ 7790.862212] WARNING: CPU: 3 PID: 26759 at arch/x86/kernel/kprobes/core.c:1022 kprobe_fault_handler+0xec/0xf0 [...] [ 7790.864113] CPU: 3 PID: 26759 Comm: sshd Not tainted 5.1.0-0.rc7.git1.1.fc31.x86_64 #1 [ 7790.864198] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS[...] [ 7790.864314] RIP: 0010:kprobe_fault_handler+0xec/0xf0 [ 7790.864375] Code: 48 8b 50 [...] [ 7790.864714] RSP: 0018:ffffc06800bdbb48 EFLAGS: 00010082 [ 7790.864812] RAX: ffff9e2b75a16320 RBX: 0000000000000000 RCX: 0000000000000000 [ 7790.865306] RDX: ffffffffffffffff RSI: 000000000000000e RDI: ffffc06800bdbbf8 [ 7790.865514] RBP: ffffc06800bdbbf8 R08: 0000000000000000 R09: 0000000000000000 [ 7790.865960] R10: 0000000000000000 R11: 0000000000000000 R12: ffffc06800bdbbf8 [ 7790.866037] R13: ffff9e2ab56a0418 R14: ffff9e2b6d0bb400 R15: ffff9e2b6d268000 [ 7790.866114] FS: 00007fde49937d80(0000) GS:ffff9e2b75a00000(0000) knlGS:0000000000000000 [ 7790.866193] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 7790.866318] CR2: 0000000000000000 CR3: 000000012f312000 CR4: 00000000000006e0 [ 7790.866419] Call Trace: [ 7790.866677] do_user_addr_fault+0x64/0x480 [ 7790.867513] do_page_fault+0x33/0x210 [ 7790.868002] async_page_fault+0x1e/0x30 [ 7790.868071] RIP: 0010: (null) [ 7790.868144] Code: Bad RIP value. [ 7790.868229] RSP: 0018:ffffc06800bdbca8 EFLAGS: 00010282 [ 7790.868362] RAX: ffff9e2b598b60f8 RBX: ffffc06800bdbe48 RCX: 0000000000000004 [ 7790.868629] RDX: 0000000000000004 RSI: ffffc06800bdbc6c RDI: ffff9e2b598b60f0 [ 7790.868834] RBP: ffffc06800bdbcf8 R08: 0000000000000000 R09: 0000000000000004 [ 7790.870432] R10: 00000000ff6f7a03 R11: 0000000000000000 R12: 0000000000000001 [ 7790.871859] R13: ffffc06800bdbcb8 R14: 0000000000000000 R15: ffff9e2acd0a5310 [ 7790.873455] ? vfs_read+0x5/0x170 [ 7790.874639] ? vfs_read+0x1/0x170 [ 7790.875834] ? trace_call_bpf+0xf6/0x260 [ 7790.877044] ? vfs_read+0x1/0x170 [ 7790.878208] ? vfs_read+0x5/0x170 [ 7790.879345] ? kprobe_perf_func+0x233/0x260 [ 7790.880503] ? vfs_read+0x1/0x170 [ 7790.881632] ? vfs_read+0x5/0x170 [ 7790.882751] ? kprobe_ftrace_handler+0x92/0xf0 [ 7790.883926] ? __vfs_read+0x30/0x30 [ 7790.885050] ? ftrace_ops_assist_func+0x94/0x100 [ 7790.886183] ? vfs_read+0x1/0x170 [ 7790.887283] ? vfs_read+0x5/0x170 [ 7790.888348] ? ksys_read+0x5a/0xe0 [ 7790.889389] ? do_syscall_64+0x5c/0xa0 [ 7790.890401] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe After some debugging, turns out that the logic in |