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| author | Kumar Kartikeya Dwivedi <memxor@gmail.com> | 2024-12-02 16:22:35 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2024-12-02 18:47:41 -0800 |
| commit | bd74e238ae6944b462f57ce8752440a011ba4530 (patch) | |
| tree | a6d52b148671d8270b985ecf8cf2547c42c96a44 /kernel/bpf | |
| parent | d4c44354bcaffed729c4eba8c0f2ecfd61fea743 (diff) | |
| download | lwn-bd74e238ae6944b462f57ce8752440a011ba4530.tar.gz lwn-bd74e238ae6944b462f57ce8752440a011ba4530.zip | |
bpf: Zero index arg error string for dynptr and iter
Andrii spotted that process_dynptr_func's rejection of incorrect
argument register type will print an error string where argument numbers
are not zero-indexed, unlike elsewhere in the verifier. Fix this by
subtracting 1 from regno. The same scenario exists for iterator
messages. Fix selftest error strings that match on the exact argument
number while we're at it to ensure clean bisection.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20241203002235.3776418-1-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/verifier.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 358a3566bb60..2fd35465d650 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -8071,7 +8071,7 @@ static int process_dynptr_func(struct bpf_verifier_env *env, int regno, int insn if (reg->type != PTR_TO_STACK && reg->type != CONST_PTR_TO_DYNPTR) { verbose(env, "arg#%d expected pointer to stack or const struct bpf_dynptr\n", - regno); + regno - 1); return -EINVAL; } @@ -8125,7 +8125,7 @@ static int process_dynptr_func(struct bpf_verifier_env *env, int regno, int insn if (!is_dynptr_reg_valid_init(env, reg)) { verbose(env, "Expected an initialized dynptr as arg #%d\n", - regno); + regno - 1); return -EINVAL; } @@ -8133,7 +8133,7 @@ static int process_dynptr_func(struct bpf_verifier_env *env, int regno, int insn if (!is_dynptr_type_expected(env, reg, arg_type & ~MEM_RDONLY)) { verbose(env, "Expected a dynptr of type %s as arg #%d\n", - dynptr_type_str(arg_to_dynptr_type(arg_type)), regno); + dynptr_type_str(arg_to_dynptr_type(arg_type)), regno - 1); return -EINVAL; } @@ -8202,7 +8202,7 @@ static int process_iter_arg(struct bpf_verifier_env *env, int regno, int insn_id */ btf_id = btf_check_iter_arg(meta->btf, meta->func_proto, regno - 1); if (btf_id < 0) { - verbose(env, "expected valid iter pointer as arg #%d\n", regno); + verbose(env, "expected valid iter pointer as arg #%d\n", regno - 1); return -EINVAL; } t = btf_type_by_id(meta->btf, btf_id); @@ -8212,7 +8212,7 @@ static int process_iter_arg(struct bpf_verifier_env *env, int regno, int insn_id /* bpf_iter_<type>_new() expects pointer to uninit iter state */ if (!is_iter_reg_valid_uninit(env, reg, nr_slots)) { verbose(env, "expected uninitialized iter_%s as arg #%d\n", - iter_type_str(meta->btf, btf_id), regno); + iter_type_str(meta->btf, btf_id), regno - 1); return -EINVAL; } @@ -8236,7 +8236,7 @@ static int process_iter_arg(struct bpf_verifier_env *env, int regno, int insn_id break; case -EINVAL: verbose(env, "expected an initialized iter_%s as arg #%d\n", - iter_type_str(meta->btf, btf_id), regno); + iter_type_str(meta->btf, btf_id), regno - 1); return err; case -EPROTO: verbose(env, "expected an RCU CS when using %s\n", meta->func_name); |