Subject: CVE-2024-26945: crypto: iaa - Fix nr_cpus < nr_iaa case

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

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

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

crypto: iaa - Fix nr_cpus < nr_iaa case

If nr_cpus < nr_iaa, the calculated cpus_per_iaa will be 0, which
causes a divide-by-0 in rebalance_wq_table().

Make sure cpus_per_iaa is 1 in that case, and also in the nr_iaa == 0
case, even though cpus_per_iaa is never used if nr_iaa == 0, for
paranoia.

The Linux kernel CVE team has assigned CVE-2024-26945 to this issue.

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

	Fixed in 6.8.3 with commit a5ca1be7f981
	Fixed in 6.9 with commit 5a7e89d3315d

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-2024-26945
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/crypto/intel/iaa/iaa_crypto_main.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/a5ca1be7f9817de4e93085778b3ee2219bdc2664
	https://git.kernel.org/stable/c/5a7e89d3315d1be86aff8a8bf849023cda6547f7