diff options
| author |   Lorenz Bauer <lmb@cloudflare.com> | 2020-09-21 13:12:23 +0100 |
|---|---|---|
| committer |   Alexei Starovoitov <ast@kernel.org> | 2020-09-21 15:00:41 -0700 |
| commit | feec70401672bd9b0268ae59ec5efd15d86ae138 (patch) | |
| tree | d3e545d04b0c1ff4aabc04fe6fa8923583c2c1dc /kernel | |
| parent | bpf: Make reference tracking generic (diff) | |
| download | linux-dev-feec70401672bd9b0268ae59ec5efd15d86ae138.tar.xz linux-dev-feec70401672bd9b0268ae59ec5efd15d86ae138.zip | |
bpf: Make context access check generic
Always check context access if the register we're operating on is
PTR_TO_CTX, rather than relying on ARG_PTR_TO_CTX. This allows
simplifying the arg_type checking section of the function.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200921121227.255763-8-lmb@cloudflare.com
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/verifier.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index a4549b2656ad..fc795bac42ed 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -4021,9 +4021,6 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, arg_type == ARG_PTR_TO_CTX_OR_NULL)) { if (type != expected_type) goto err_type; - err = check_ctx_reg(env, reg, regno); - if (err < 0) - return err; } } else if (arg_type == ARG_PTR_TO_SOCK_COMMON) { expected_type = PTR_TO_SOCK_COMMON; @@ -4107,6 +4104,10 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg, regno); return -EACCES; } + } else if (type == PTR_TO_CTX) { + err = check_ctx_reg(env, reg, regno); + if (err < 0) + return err; } if (reg->ref_obj_id) { |