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From:   Casey Schaufler <casey@schaufler-ca.com>
Subject: Regression in unix stream sockets with the Smack LSM
Cc:     Casey Schaufler <casey@schaufler-ca.com>
Message-ID: <a507efa7-066b-decf-8605-89cdb0ac1951@schaufler-ca.com>
Date:   Mon, 13 Sep 2021 15:50:55 -0700
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Commit 77462de14a43f4d98dbd8de0f5743a4e02450b1d=20

	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.

Thank you.