CVE-2023-52672 Affecting kernel-64kb-devel package, versions <6.4.0-150600.23.14.1

Note: Versions mentioned in the description apply only to the upstream kernel-64kb-devel package and not the kernel-64kb-devel package as distributed by SLES. See How to fix? for SLES:15.6 relevant fixed versions and status.

In the Linux kernel, the following vulnerability has been resolved:

pipe: wakeup wr_wait after setting max_usage

Commit c73be61cede5 ("pipe: Add general notification queue support") a regression was introduced that would lock up resized pipes under certain conditions. See the reproducer in [1].

The commit resizing the pipe ring size was moved to a different function, doing that moved the wakeup for pipe->wr_wait before actually raising pipe->max_usage. If a pipe was full before the resize occured it would result in the wakeup never actually triggering pipe_write.

Set @max_usage and @nr_accounted before waking writers if this isn't a watch queue.

[Christian Brauner <brauner@kernel.org>: rewrite to account for watch queues]

• https://www.suse.com/security/cve/CVE-2023-52672.html
• https://bugzilla.suse.com/1224614
• https://git.kernel.org/stable/c/162ae0e78bdabf84ef10c1293c4ed7865cb7d3c8
• https://git.kernel.org/stable/c/3efbd114b91525bb095b8ae046382197d92126b9
• https://git.kernel.org/stable/c/68e51bdb1194f11d3452525b99c98aff6f837b24
• https://git.kernel.org/stable/c/6fb70694f8d1ac34e45246b0ac988f025e1e5b55
• https://git.kernel.org/stable/c/b87a1229d8668fbc78ebd9ca0fc797a76001c60f
• https://git.kernel.org/stable/c/e95aada4cb93d42e25c30a0ef9eb2923d9711d4a
• https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html