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Date: Mon, 17 Aug 2026 08:41:23 -0700
From: Jakub Kicinski <kuba@kernel.org>
To: Lei Zhu <zhulei_szu@163.com>
Cc: netdev@vger.kernel.org, linux-kselftest@vger.kernel.org,
 kuniyu@google.com, davem@davemloft.net, edumazet@google.com,
 pabeni@redhat.com, horms@kernel.org, shuah@kernel.org
Subject: Re: [PATCH net] selftests: af_unix: verify SCM_PIDFD pidfd in
 cmsg_check_dead()
Message-ID: <20260817084123.75fbbf97@kernel.org>
In-Reply-To: <20260817061121.239648-1-zhulei_szu@163.com>
References: <20260817061121.239648-1-zhulei_szu@163.com>
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On Mon, 17 Aug 2026 14:11:21 +0800 Lei Zhu wrote:
> The cmsg_check_dead() function receives an expected_pid parameter but never
> actually verifies that the pidfd received via SCM_PIDFD corresponds to that
> PID. It only checks the child's exit code via PIDFD_GET_INFO.

this breaks the test:

  (scm_pidfd.c:282: errno: None) wrong SCM_PIDFD -1 != <PID>

If you want to improve the test please repost this patch in 2 weeks
after the merge window. This patch should not carry the Fixes tag.