From: Eduard Zingerman <eddyz87@gmail.com>
To: Sun Jian <sun.jian.kdev@gmail.com>, bpf@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
ast@kernel.org, daniel@iogearbox.net, john.fastabend@gmail.com,
andrii@kernel.org, martin.lau@linux.dev, memxor@gmail.com,
song@kernel.org, yonghong.song@linux.dev, jolsa@kernel.org,
shuah@kernel.org, dxu@dxuuu.xyz
Subject: Re: [PATCH bpf 1/2] bpf: Avoid eliding lookup NULLness for inner map templates
Date: Thu, 25 Jun 2026 11:53:13 -0700 [thread overview]
Message-ID: <01858c50447df77199abbe570d3ce06288200721.camel@gmail.com> (raw)
In-Reply-To: <20260624072031.735846-1-sun.jian.kdev@gmail.com>
On Wed, 2026-06-24 at 15:20 +0800, Sun Jian wrote:
> Commit d2102f2f5d75 ("bpf: verifier: Support eliding map lookup
> nullness") allowed the verifier to elide NULLness of
> bpf_map_lookup_elem() for array maps when the key is statically known to
> be within max_entries.
>
> This is not valid for array maps used as inner map templates. For such
> maps, the template's max_entries is not necessarily the same as the
> max_entries of the concrete inner map used at runtime. As a result, a
> key that is within the template's max_entries can still be out of range
> for the concrete inner map, and the lookup may return NULL.
>
> Do not elide lookup NULLness for array maps used as inner map templates.
>
> Fixes: d2102f2f5d75 ("bpf: verifier: Support eliding map lookup nullness")
> Signed-off-by: Sun Jian <sun.jian.kdev@gmail.com>
> ---
This was already fixed by commit:
53040a81ae57 ("bpf: Keep dynamic inner array lookups nullable")
Please do not send stale patches.
[...]
next prev parent reply other threads:[~2026-06-25 18:53 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-06-24 7:20 Sun Jian
2026-06-24 7:20 ` [PATCH bpf 2/2] selftests/bpf: Add inner map template lookup NULLness test Sun Jian
2026-06-25 18:53 ` Eduard Zingerman [this message]
2026-06-26 0:44 ` [PATCH bpf 1/2] bpf: Avoid eliding lookup NULLness for inner map templates sun jian
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