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From:   Paul Moore <paul@paul-moore.com>
Date:   Mon, 13 Sep 2021 19:47:53 -0400
Message-ID: <CAHC9VhR9SKX_-SAmtcCj+vuUvcdq-SWzKs86BKMjBcC8GhJ1gg@mail.gmail.com>
Subject: Re: Regression in unix stream sockets with the Smack LSM
To:     Casey Schaufler <casey@schaufler-ca.com>
Cc:     Jiang Wang <jiang.wang@bytedance.com>,
        Andrii Nakryiko <andrii@kernel.org>,
        Jakub Sitnicki <jakub@cloudflare.com>,
        John Fastabend <john.fastabend@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux Security Module list 
        <linux-security-module@vger.kernel.org>
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On Mon, Sep 13, 2021 at 6:53 PM Casey Schaufler <casey@schaufler-ca.com> wrote:
>
> Commit 77462de14a43f4d98dbd8de0f5743a4e02450b1d
>
>         af_unix: Add read_sock for stream socket types
>
> introduced a regression in UDS socket connections for the Smack LSM.
> I have not tracked done the details of why the change broke the code,
> but this is where bisecting the kernel indicates the problem lies, and
> I have verified that reverting this change repairs the problem.
>
> You can verify the problem with the Smack test suite:
>
>         https://github.com/smack-team/smack-testsuite.git
>
> The failing test is tests/uds-access.sh.
>
> I have not looked to see if there's a similar problem with SELinux.
> There may be, but if there isn't it doesn't matter, there's still a
> bug.

FWIW, the selinux-testsuite tests ran clean today with v5.15-rc1 (it
looks like this code is only in v5.15) but as Casey said, a regression
is a regression.

Casey, what actually fails on the Smack system with this commit?

-- 
paul moore
www.paul-moore.com