From: Brendan Jackman <jackmanb@google.com>
To: bpf@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>,
Andrii Nakryiko <andrii.nakryiko@gmail.com>,
KP Singh <kpsingh@chromium.org>,
Florent Revest <revest@chromium.org>,
linux-kernel@vger.kernel.org,
Brendan Jackman <jackmanb@google.com>
Subject: [PATCH bpf-next] bpf: Fix a verifier message for alloc size helper arg
Date: Tue, 12 Jan 2021 12:39:13 +0000 [thread overview]
Message-ID: <20210112123913.2016804-1-jackmanb@google.com> (raw)
The error message here is misleading, the argument will be rejected
unless it is a known constant.
Signed-off-by: Brendan Jackman <jackmanb@google.com>
---
kernel/bpf/verifier.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 17270b8404f1..5534e667bdb1 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -4319,7 +4319,7 @@ static int check_func_arg(struct bpf_verifier_env *env, u32 arg,
err = mark_chain_precision(env, regno);
} else if (arg_type_is_alloc_size(arg_type)) {
if (!tnum_is_const(reg->var_off)) {
- verbose(env, "R%d unbounded size, use 'var &= const' or 'if (var < const)'\n",
+ verbose(env, "R%d is not a known constant'\n",
regno);
return -EACCES;
}
base-commit: e22d7f05e445165e58feddb4e40cc9c0f94453bc
--
2.30.0.284.gd98b1dd5eaa7-goog
next reply other threads:[~2021-01-12 12:40 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-12 12:39 Brendan Jackman [this message]
2021-01-12 13:14 ` [PATCH bpf-next] bpf: Fix a verifier message for alloc size helper arg KP Singh
2021-01-12 14:55 ` Brendan Jackman
2021-01-12 16:42 ` Yonghong Song
2021-01-12 19:16 ` Andrii Nakryiko
2021-01-12 20:50 ` patchwork-bot+netdevbpf
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