Subject: CVE-2024-36922: wifi: iwlwifi: read txq->read_ptr under lock

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

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

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

wifi: iwlwifi: read txq->read_ptr under lock

If we read txq->read_ptr without lock, we can read the same
value twice, then obtain the lock, and reclaim from there
to two different places, but crucially reclaim the same
entry twice, resulting in the WARN_ONCE() a little later.
Fix that by reading txq->read_ptr under lock.

The Linux kernel CVE team has assigned CVE-2024-36922 to this issue.

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

	Fixed in 6.6.31 with commit b83db8e756de
	Fixed in 6.8.10 with commit 43d07103df67
	Fixed in 6.9 with commit c2ace6300600

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-2024-36922
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:
	drivers/net/wireless/intel/iwlwifi/queue/tx.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/b83db8e756dec68a950ed2f056248b1704b3deaa
	https://git.kernel.org/stable/c/43d07103df670484cdd26f9588eabef80f69db89
	https://git.kernel.org/stable/c/c2ace6300600c634553657785dfe5ea0ed688ac2