Subject: CVE-2024-49956: gfs2: fix double destroy_workqueue error

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

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

gfs2: fix double destroy_workqueue error

When gfs2_fill_super() fails, destroy_workqueue() is called within
gfs2_gl_hash_clear(), and the subsequent code path calls
destroy_workqueue() on the same work queue again.

This issue can be fixed by setting the work queue pointer to NULL after
the first destroy_workqueue() call and checking for a NULL pointer
before attempting to destroy the work queue again.

The Linux kernel CVE team has assigned CVE-2024-49956 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 6.11 with commit 30e388d57367 and fixed in 6.11.3 with commit a5336035728d
	Issue introduced in 6.11 with commit 30e388d57367 and fixed in 6.12-rc1 with commit 6cb9df81a2c4

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-49956
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	fs/gfs2/glock.c
	fs/gfs2/ops_fstype.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/a5336035728d77efd76306940d742a6f23debe68
	https://git.kernel.org/stable/c/6cb9df81a2c462b89d2f9611009ab43ae8717841