mirror of https://github.com/torvalds/linux.git
bpf, x86: add support for indirect jumps
Add support for a new instruction
BPF_JMP|BPF_X|BPF_JA, SRC=0, DST=Rx, off=0, imm=0
which does an indirect jump to a location stored in Rx. The register
Rx should have type PTR_TO_INSN. This new type assures that the Rx
register contains a value (or a range of values) loaded from a
correct jump table – map of type instruction array.
For example, for a C switch LLVM will generate the following code:
0: r3 = r1 # "switch (r3)"
1: if r3 > 0x13 goto +0x666 # check r3 boundaries
2: r3 <<= 0x3 # adjust to an index in array of addresses
3: r1 = 0xbeef ll # r1 is PTR_TO_MAP_VALUE, r1->map_ptr=M
5: r1 += r3 # r1 inherits boundaries from r3
6: r1 = *(u64 *)(r1 + 0x0) # r1 now has type INSN_TO_PTR
7: gotox r1 # jit will generate proper code
Here the gotox instruction corresponds to one particular map. This is
possible however to have a gotox instruction which can be loaded from
different maps, e.g.
0: r1 &= 0x1
1: r2 <<= 0x3
2: r3 = 0x0 ll # load from map M_1
4: r3 += r2
5: if r1 == 0x0 goto +0x4
6: r1 <<= 0x3
7: r3 = 0x0 ll # load from map M_2
9: r3 += r1
A: r1 = *(u64 *)(r3 + 0x0)
B: gotox r1 # jump to target loaded from M_1 or M_2
During check_cfg stage the verifier will collect all the maps which
point to inside the subprog being verified. When building the config,
the high 16 bytes of the insn_state are used, so this patch
(theoretically) supports jump tables of up to 2^16 slots.
During the later stage, in check_indirect_jump, it is checked that
the register Rx was loaded from a particular instruction array.
Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20251105090410.1250500-9-a.s.protopopov@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
parent
5bef46ac9c
commit
493d9e0d60
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@ -2628,6 +2628,9 @@ st: if (is_imm8(insn->off))
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break;
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case BPF_JMP | BPF_JA | BPF_X:
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emit_indirect_jump(&prog, insn->dst_reg, image + addrs[i - 1]);
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break;
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case BPF_JMP | BPF_JA:
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case BPF_JMP32 | BPF_JA:
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if (BPF_CLASS(insn->code) == BPF_JMP) {
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@ -1001,6 +1001,7 @@ enum bpf_reg_type {
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PTR_TO_ARENA,
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PTR_TO_BUF, /* reg points to a read/write buffer */
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PTR_TO_FUNC, /* reg points to a bpf program function */
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PTR_TO_INSN, /* reg points to a bpf program instruction */
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CONST_PTR_TO_DYNPTR, /* reg points to a const struct bpf_dynptr */
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__BPF_REG_TYPE_MAX,
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@ -527,6 +527,7 @@ struct bpf_insn_aux_data {
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struct {
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u32 map_index; /* index into used_maps[] */
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u32 map_off; /* offset from value base address */
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struct bpf_iarray *jt; /* jump table for gotox instruction */
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};
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struct {
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enum bpf_reg_type reg_type; /* type of pseudo_btf_id */
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@ -840,6 +841,7 @@ struct bpf_verifier_env {
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struct bpf_scc_info **scc_info;
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u32 scc_cnt;
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struct bpf_iarray *succ;
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struct bpf_iarray *gotox_tmp_buf;
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};
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static inline struct bpf_func_info_aux *subprog_aux(struct bpf_verifier_env *env, int subprog)
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@ -1050,6 +1052,13 @@ static inline bool bpf_stack_narrow_access_ok(int off, int fill_size, int spill_
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return !(off % BPF_REG_SIZE);
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}
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static inline bool insn_is_gotox(struct bpf_insn *insn)
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{
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return BPF_CLASS(insn->code) == BPF_JMP &&
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BPF_OP(insn->code) == BPF_JA &&
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BPF_SRC(insn->code) == BPF_X;
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}
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const char *reg_type_str(struct bpf_verifier_env *env, enum bpf_reg_type type);
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const char *dynptr_type_str(enum bpf_dynptr_type type);
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const char *iter_type_str(const struct btf *btf, u32 btf_id);
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@ -114,6 +114,20 @@ static u64 insn_array_mem_usage(const struct bpf_map *map)
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return insn_array_alloc_size(map->max_entries);
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}
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static int insn_array_map_direct_value_addr(const struct bpf_map *map, u64 *imm, u32 off)
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{
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struct bpf_insn_array *insn_array = cast_insn_array(map);
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if ((off % sizeof(long)) != 0 ||
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(off / sizeof(long)) >= map->max_entries)
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return -EINVAL;
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/* from BPF's point of view, this map is a jump table */
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*imm = (unsigned long)insn_array->ips + off;
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return 0;
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}
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BTF_ID_LIST_SINGLE(insn_array_btf_ids, struct, bpf_insn_array)
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const struct bpf_map_ops insn_array_map_ops = {
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@ -126,6 +140,7 @@ const struct bpf_map_ops insn_array_map_ops = {
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.map_delete_elem = insn_array_delete_elem,
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.map_check_btf = insn_array_check_btf,
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.map_mem_usage = insn_array_mem_usage,
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.map_direct_value_addr = insn_array_map_direct_value_addr,
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.map_btf_id = &insn_array_btf_ids[0],
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};
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@ -1708,6 +1708,7 @@ bool bpf_opcode_in_insntable(u8 code)
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[BPF_LD | BPF_IND | BPF_B] = true,
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[BPF_LD | BPF_IND | BPF_H] = true,
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[BPF_LD | BPF_IND | BPF_W] = true,
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[BPF_JMP | BPF_JA | BPF_X] = true,
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[BPF_JMP | BPF_JCOND] = true,
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};
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#undef BPF_INSN_3_TBL
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@ -485,6 +485,9 @@ bpf_insn_successors(struct bpf_verifier_env *env, u32 idx)
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struct bpf_iarray *succ;
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int insn_sz;
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if (unlikely(insn_is_gotox(insn)))
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return env->insn_aux_data[idx].jt;
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/* pre-allocated array of size up to 2; reset cnt, as it may have been used already */
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succ = env->succ;
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succ->cnt = 0;
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@ -461,6 +461,7 @@ const char *reg_type_str(struct bpf_verifier_env *env, enum bpf_reg_type type)
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[PTR_TO_ARENA] = "arena",
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[PTR_TO_BUF] = "buf",
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[PTR_TO_FUNC] = "func",
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[PTR_TO_INSN] = "insn",
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[PTR_TO_MAP_KEY] = "map_key",
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[CONST_PTR_TO_DYNPTR] = "dynptr_ptr",
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};
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@ -6006,6 +6006,18 @@ static int check_map_kptr_access(struct bpf_verifier_env *env, u32 regno,
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return 0;
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}
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/*
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* Return the size of the memory region accessible from a pointer to map value.
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* For INSN_ARRAY maps whole bpf_insn_array->ips array is accessible.
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*/
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static u32 map_mem_size(const struct bpf_map *map)
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{
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if (map->map_type == BPF_MAP_TYPE_INSN_ARRAY)
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return map->max_entries * sizeof(long);
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return map->value_size;
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}
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/* check read/write into a map element with possible variable offset */
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static int check_map_access(struct bpf_verifier_env *env, u32 regno,
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int off, int size, bool zero_size_allowed,
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@ -6015,11 +6027,11 @@ static int check_map_access(struct bpf_verifier_env *env, u32 regno,
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struct bpf_func_state *state = vstate->frame[vstate->curframe];
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struct bpf_reg_state *reg = &state->regs[regno];
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struct bpf_map *map = reg->map_ptr;
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u32 mem_size = map_mem_size(map);
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struct btf_record *rec;
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int err, i;
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err = check_mem_region_access(env, regno, off, size, map->value_size,
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zero_size_allowed);
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err = check_mem_region_access(env, regno, off, size, mem_size, zero_size_allowed);
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if (err)
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return err;
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@ -7481,6 +7493,8 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
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{
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struct bpf_reg_state *regs = cur_regs(env);
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struct bpf_reg_state *reg = regs + regno;
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bool insn_array = reg->type == PTR_TO_MAP_VALUE &&
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reg->map_ptr->map_type == BPF_MAP_TYPE_INSN_ARRAY;
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int size, err = 0;
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size = bpf_size_to_bytes(bpf_size);
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@ -7488,7 +7502,7 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
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return size;
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/* alignment checks will add in reg->off themselves */
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err = check_ptr_alignment(env, reg, off, size, strict_alignment_once);
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err = check_ptr_alignment(env, reg, off, size, strict_alignment_once || insn_array);
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if (err)
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return err;
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@ -7515,6 +7529,11 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
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verbose(env, "R%d leaks addr into map\n", value_regno);
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return -EACCES;
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}
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if (t == BPF_WRITE && insn_array) {
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verbose(env, "writes into insn_array not allowed\n");
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return -EACCES;
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}
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err = check_map_access_type(env, regno, off, size, t);
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if (err)
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return err;
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@ -7543,6 +7562,14 @@ static int check_mem_access(struct bpf_verifier_env *env, int insn_idx, u32 regn
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regs[value_regno].type = SCALAR_VALUE;
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__mark_reg_known(®s[value_regno], val);
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} else if (map->map_type == BPF_MAP_TYPE_INSN_ARRAY) {
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if (bpf_size != BPF_DW) {
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verbose(env, "Invalid read of %d bytes from insn_array\n",
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size);
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return -EACCES;
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}
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copy_register_state(®s[value_regno], reg);
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regs[value_regno].type = PTR_TO_INSN;
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} else {
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mark_reg_unknown(env, regs, value_regno);
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}
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@ -17096,7 +17123,8 @@ static int check_ld_imm(struct bpf_verifier_env *env, struct bpf_insn *insn)
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}
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dst_reg->type = PTR_TO_MAP_VALUE;
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dst_reg->off = aux->map_off;
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WARN_ON_ONCE(map->max_entries != 1);
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WARN_ON_ONCE(map->map_type != BPF_MAP_TYPE_INSN_ARRAY &&
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map->max_entries != 1);
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/* We want reg->id to be same (0) as map_value is not distinct */
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} else if (insn->src_reg == BPF_PSEUDO_MAP_FD ||
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insn->src_reg == BPF_PSEUDO_MAP_IDX) {
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@ -17864,6 +17892,206 @@ static struct bpf_iarray *iarray_realloc(struct bpf_iarray *old, size_t n_elem)
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return new;
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}
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static int copy_insn_array(struct bpf_map *map, u32 start, u32 end, u32 *items)
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{
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struct bpf_insn_array_value *value;
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u32 i;
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for (i = start; i <= end; i++) {
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value = map->ops->map_lookup_elem(map, &i);
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if (!value)
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return -EINVAL;
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items[i - start] = value->xlated_off;
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}
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return 0;
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}
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static int cmp_ptr_to_u32(const void *a, const void *b)
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{
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return *(u32 *)a - *(u32 *)b;
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}
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static int sort_insn_array_uniq(u32 *items, int cnt)
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{
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int unique = 1;
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int i;
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sort(items, cnt, sizeof(items[0]), cmp_ptr_to_u32, NULL);
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for (i = 1; i < cnt; i++)
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if (items[i] != items[unique - 1])
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items[unique++] = items[i];
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return unique;
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}
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/*
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* sort_unique({map[start], ..., map[end]}) into off
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*/
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static int copy_insn_array_uniq(struct bpf_map *map, u32 start, u32 end, u32 *off)
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{
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u32 n = end - start + 1;
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int err;
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err = copy_insn_array(map, start, end, off);
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if (err)
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return err;
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return sort_insn_array_uniq(off, n);
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}
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/*
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* Copy all unique offsets from the map
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*/
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static struct bpf_iarray *jt_from_map(struct bpf_map *map)
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{
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struct bpf_iarray *jt;
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int err;
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int n;
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jt = iarray_realloc(NULL, map->max_entries);
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if (!jt)
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return ERR_PTR(-ENOMEM);
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n = copy_insn_array_uniq(map, 0, map->max_entries - 1, jt->items);
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if (n < 0) {
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err = n;
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goto err_free;
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}
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if (n == 0) {
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err = -EINVAL;
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goto err_free;
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}
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jt->cnt = n;
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return jt;
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err_free:
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kvfree(jt);
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return ERR_PTR(err);
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}
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/*
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* Find and collect all maps which fit in the subprog. Return the result as one
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* combined jump table in jt->items (allocated with kvcalloc)
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*/
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static struct bpf_iarray *jt_from_subprog(struct bpf_verifier_env *env,
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int subprog_start, int subprog_end)
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{
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struct bpf_iarray *jt = NULL;
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struct bpf_map *map;
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struct bpf_iarray *jt_cur;
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int i;
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for (i = 0; i < env->insn_array_map_cnt; i++) {
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/*
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* TODO (when needed): collect only jump tables, not static keys
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* or maps for indirect calls
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*/
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map = env->insn_array_maps[i];
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jt_cur = jt_from_map(map);
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if (IS_ERR(jt_cur)) {
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kvfree(jt);
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return jt_cur;
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}
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/*
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* This is enough to check one element. The full table is
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* checked to fit inside the subprog later in create_jt()
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*/
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if (jt_cur->items[0] >= subprog_start && jt_cur->items[0] < subprog_end) {
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u32 old_cnt = jt ? jt->cnt : 0;
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jt = iarray_realloc(jt, old_cnt + jt_cur->cnt);
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if (!jt) {
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kvfree(jt_cur);
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return ERR_PTR(-ENOMEM);
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}
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memcpy(jt->items + old_cnt, jt_cur->items, jt_cur->cnt << 2);
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}
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kvfree(jt_cur);
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}
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if (!jt) {
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verbose(env, "no jump tables found for subprog starting at %u\n", subprog_start);
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return ERR_PTR(-EINVAL);
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}
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jt->cnt = sort_insn_array_uniq(jt->items, jt->cnt);
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return jt;
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}
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static struct bpf_iarray *
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create_jt(int t, struct bpf_verifier_env *env)
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{
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static struct bpf_subprog_info *subprog;
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int subprog_start, subprog_end;
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struct bpf_iarray *jt;
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int i;
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subprog = bpf_find_containing_subprog(env, t);
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subprog_start = subprog->start;
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subprog_end = (subprog + 1)->start;
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jt = jt_from_subprog(env, subprog_start, subprog_end);
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if (IS_ERR(jt))
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return jt;
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/* Check that the every element of the jump table fits within the given subprogram */
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for (i = 0; i < jt->cnt; i++) {
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if (jt->items[i] < subprog_start || jt->items[i] >= subprog_end) {
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verbose(env, "jump table for insn %d points outside of the subprog [%u,%u]\n",
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t, subprog_start, subprog_end);
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kvfree(jt);
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return ERR_PTR(-EINVAL);
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}
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}
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return jt;
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}
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/* "conditional jump with N edges" */
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static int visit_gotox_insn(int t, struct bpf_verifier_env *env)
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{
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int *insn_stack = env->cfg.insn_stack;
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int *insn_state = env->cfg.insn_state;
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bool keep_exploring = false;
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struct bpf_iarray *jt;
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int i, w;
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jt = env->insn_aux_data[t].jt;
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if (!jt) {
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jt = create_jt(t, env);
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if (IS_ERR(jt))
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return PTR_ERR(jt);
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env->insn_aux_data[t].jt = jt;
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}
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mark_prune_point(env, t);
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for (i = 0; i < jt->cnt; i++) {
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w = jt->items[i];
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if (w < 0 || w >= env->prog->len) {
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verbose(env, "indirect jump out of range from insn %d to %d\n", t, w);
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return -EINVAL;
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}
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mark_jmp_point(env, w);
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/* EXPLORED || DISCOVERED */
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if (insn_state[w])
|
||||
continue;
|
||||
|
||||
if (env->cfg.cur_stack >= env->prog->len)
|
||||
return -E2BIG;
|
||||
|
||||
insn_stack[env->cfg.cur_stack++] = w;
|
||||
insn_state[w] |= DISCOVERED;
|
||||
keep_exploring = true;
|
||||
}
|
||||
|
||||
return keep_exploring ? KEEP_EXPLORING : DONE_EXPLORING;
|
||||
}
|
||||
|
||||
/* Visits the instruction at index t and returns one of the following:
|
||||
* < 0 - an error occurred
|
||||
* DONE_EXPLORING - the instruction was fully explored
|
||||
|
|
@ -17956,8 +18184,8 @@ static int visit_insn(int t, struct bpf_verifier_env *env)
|
|||
return visit_func_call_insn(t, insns, env, insn->src_reg == BPF_PSEUDO_CALL);
|
||||
|
||||
case BPF_JA:
|
||||
if (BPF_SRC(insn->code) != BPF_K)
|
||||
return -EINVAL;
|
||||
if (BPF_SRC(insn->code) == BPF_X)
|
||||
return visit_gotox_insn(t, env);
|
||||
|
||||
if (BPF_CLASS(insn->code) == BPF_JMP)
|
||||
off = insn->off;
|
||||
|
|
@ -18886,6 +19114,10 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold,
|
|||
return regs_exact(rold, rcur, idmap) && rold->frameno == rcur->frameno;
|
||||
case PTR_TO_ARENA:
|
||||
return true;
|
||||
case PTR_TO_INSN:
|
||||
return memcmp(rold, rcur, offsetof(struct bpf_reg_state, var_off)) == 0 &&
|
||||
rold->off == rcur->off && range_within(rold, rcur) &&
|
||||
tnum_in(rold->var_off, rcur->var_off);
|
||||
default:
|
||||
return regs_exact(rold, rcur, idmap);
|
||||
}
|
||||
|
|
@ -19895,6 +20127,99 @@ static int process_bpf_exit_full(struct bpf_verifier_env *env,
|
|||
return PROCESS_BPF_EXIT;
|
||||
}
|
||||
|
||||
static int indirect_jump_min_max_index(struct bpf_verifier_env *env,
|
||||
int regno,
|
||||
struct bpf_map *map,
|
||||
u32 *pmin_index, u32 *pmax_index)
|
||||
{
|
||||
struct bpf_reg_state *reg = reg_state(env, regno);
|
||||
u64 min_index, max_index;
|
||||
const u32 size = 8;
|
||||
|
||||
if (check_add_overflow(reg->umin_value, reg->off, &min_index) ||
|
||||
(min_index > (u64) U32_MAX * size)) {
|
||||
verbose(env, "the sum of R%u umin_value %llu and off %u is too big\n",
|
||||
regno, reg->umin_value, reg->off);
|
||||
return -ERANGE;
|
||||
}
|
||||
if (check_add_overflow(reg->umax_value, reg->off, &max_index) ||
|
||||
(max_index > (u64) U32_MAX * size)) {
|
||||
verbose(env, "the sum of R%u umax_value %llu and off %u is too big\n",
|
||||
regno, reg->umax_value, reg->off);
|
||||
return -ERANGE;
|
||||
}
|
||||
|
||||
min_index /= size;
|
||||
max_index /= size;
|
||||
|
||||
if (max_index >= map->max_entries) {
|
||||
verbose(env, "R%u points to outside of jump table: [%llu,%llu] max_entries %u\n",
|
||||
regno, min_index, max_index, map->max_entries);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
*pmin_index = min_index;
|
||||
*pmax_index = max_index;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* gotox *dst_reg */
|
||||
static int check_indirect_jump(struct bpf_verifier_env *env, struct bpf_insn *insn)
|
||||
{
|
||||
struct bpf_verifier_state *other_branch;
|
||||
struct bpf_reg_state *dst_reg;
|
||||
struct bpf_map *map;
|
||||
u32 min_index, max_index;
|
||||
int err = 0;
|
||||
int n;
|
||||
int i;
|
||||
|
||||
dst_reg = reg_state(env, insn->dst_reg);
|
||||
if (dst_reg->type != PTR_TO_INSN) {
|
||||
verbose(env, "R%d has type %s, expected PTR_TO_INSN\n",
|
||||
insn->dst_reg, reg_type_str(env, dst_reg->type));
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
map = dst_reg->map_ptr;
|
||||
if (verifier_bug_if(!map, env, "R%d has an empty map pointer", insn->dst_reg))
|
||||
return -EFAULT;
|
||||
|
||||
if (verifier_bug_if(map->map_type != BPF_MAP_TYPE_INSN_ARRAY, env,
|
||||
"R%d has incorrect map type %d", insn->dst_reg, map->map_type))
|
||||
return -EFAULT;
|
||||
|
||||
err = indirect_jump_min_max_index(env, insn->dst_reg, map, &min_index, &max_index);
|
||||
if (err)
|
||||
return err;
|
||||
|
||||
/* Ensure that the buffer is large enough */
|
||||
if (!env->gotox_tmp_buf || env->gotox_tmp_buf->cnt < max_index - min_index + 1) {
|
||||
env->gotox_tmp_buf = iarray_realloc(env->gotox_tmp_buf,
|
||||
max_index - min_index + 1);
|
||||
if (!env->gotox_tmp_buf)
|
||||
return -ENOMEM;
|
||||
}
|
||||
|
||||
n = copy_insn_array_uniq(map, min_index, max_index, env->gotox_tmp_buf->items);
|
||||
if (n < 0)
|
||||
return n;
|
||||
if (n == 0) {
|
||||
verbose(env, "register R%d doesn't point to any offset in map id=%d\n",
|
||||
insn->dst_reg, map->id);
|
||||
return -EINVAL;
|
||||
}
|
||||
|
||||
for (i = 0; i < n - 1; i++) {
|
||||
other_branch = push_stack(env, env->gotox_tmp_buf->items[i],
|
||||
env->insn_idx, env->cur_state->speculative);
|
||||
if (IS_ERR(other_branch))
|
||||
return PTR_ERR(other_branch);
|
||||
}
|
||||
env->insn_idx = env->gotox_tmp_buf->items[n-1];
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int do_check_insn(struct bpf_verifier_env *env, bool *do_print_state)
|
||||
{
|
||||
int err;
|
||||
|
|
@ -19997,6 +20322,15 @@ static int do_check_insn(struct bpf_verifier_env *env, bool *do_print_state)
|
|||
|
||||
mark_reg_scratched(env, BPF_REG_0);
|
||||
} else if (opcode == BPF_JA) {
|
||||
if (BPF_SRC(insn->code) == BPF_X) {
|
||||
if (insn->src_reg != BPF_REG_0 ||
|
||||
insn->imm != 0 || insn->off != 0) {
|
||||
verbose(env, "BPF_JA|BPF_X uses reserved fields\n");
|
||||
return -EINVAL;
|
||||
}
|
||||
return check_indirect_jump(env, insn);
|
||||
}
|
||||
|
||||
if (BPF_SRC(insn->code) != BPF_K ||
|
||||
insn->src_reg != BPF_REG_0 ||
|
||||
insn->dst_reg != BPF_REG_0 ||
|
||||
|
|
@ -20513,6 +20847,7 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env,
|
|||
case BPF_MAP_TYPE_QUEUE:
|
||||
case BPF_MAP_TYPE_STACK:
|
||||
case BPF_MAP_TYPE_ARENA:
|
||||
case BPF_MAP_TYPE_INSN_ARRAY:
|
||||
break;
|
||||
default:
|
||||
verbose(env,
|
||||
|
|
@ -21070,6 +21405,27 @@ static int bpf_adj_linfo_after_remove(struct bpf_verifier_env *env, u32 off,
|
|||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Clean up dynamically allocated fields of aux data for instructions [start, ...]
|
||||
*/
|
||||
static void clear_insn_aux_data(struct bpf_verifier_env *env, int start, int len)
|
||||
{
|
||||
struct bpf_insn_aux_data *aux_data = env->insn_aux_data;
|
||||
struct bpf_insn *insns = env->prog->insnsi;
|
||||
int end = start + len;
|
||||
int i;
|
||||
|
||||
for (i = start; i < end; i++) {
|
||||
if (insn_is_gotox(&insns[i])) {
|
||||
kvfree(aux_data[i].jt);
|
||||
aux_data[i].jt = NULL;
|
||||
}
|
||||
|
||||
if (bpf_is_ldimm64(&insns[i]))
|
||||
i++;
|
||||
}
|
||||
}
|
||||
|
||||
static int verifier_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt)
|
||||
{
|
||||
struct bpf_insn_aux_data *aux_data = env->insn_aux_data;
|
||||
|
|
@ -21079,6 +21435,9 @@ static int verifier_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt)
|
|||
if (bpf_prog_is_offloaded(env->prog->aux))
|
||||
bpf_prog_offload_remove_insns(env, off, cnt);
|
||||
|
||||
/* Should be called before bpf_remove_insns, as it uses prog->insnsi */
|
||||
clear_insn_aux_data(env, off, cnt);
|
||||
|
||||
err = bpf_remove_insns(env->prog, off, cnt);
|
||||
if (err)
|
||||
return err;
|
||||
|
|
@ -24945,12 +25304,14 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u3
|
|||
err_unlock:
|
||||
if (!is_priv)
|
||||
mutex_unlock(&bpf_verifier_lock);
|
||||
clear_insn_aux_data(env, 0, env->prog->len);
|
||||
vfree(env->insn_aux_data);
|
||||
err_free_env:
|
||||
bpf_stack_liveness_free(env);
|
||||
kvfree(env->cfg.insn_postorder);
|
||||
kvfree(env->scc_info);
|
||||
kvfree(env->succ);
|
||||
kvfree(env->gotox_tmp_buf);
|
||||
kvfree(env);
|
||||
return ret;
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue