Subject: CVE-2024-42094: net/iucv: Avoid explicit cpumask var allocation on stack

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

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

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

net/iucv: Avoid explicit cpumask var allocation on stack

For CONFIG_CPUMASK_OFFSTACK=y kernel, explicit allocation of cpumask
variable on stack is not recommended since it can cause potential stack
overflow.

Instead, kernel code should always use *cpumask_var API(s) to allocate
cpumask var in config-neutral way, leaving allocation strategy to
CONFIG_CPUMASK_OFFSTACK.

Use *cpumask_var API(s) to address it.

The Linux kernel CVE team has assigned CVE-2024-42094 to this issue.

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

	Fixed in 4.19.317 with commit 2b085521be52
	Fixed in 5.4.279 with commit 842afb47d845
	Fixed in 5.10.221 with commit 9dadab0db7d9
	Fixed in 5.15.162 with commit 0af718a690ac
	Fixed in 6.1.97 with commit d85ca8179a54
	Fixed in 6.6.37 with commit 724e7965af05
	Fixed in 6.9.8 with commit 2d090c7f7be3
	Fixed in 6.10 with commit be4e1304419c

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-2024-42094
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:
	net/iucv/iucv.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/2b085521be5292016097b5e7ca81b26be3f7098d
	https://git.kernel.org/stable/c/842afb47d84536fc976fece8fb6c54bea711ad1a
	https://git.kernel.org/stable/c/9dadab0db7d904413ea1cdaa13f127da05c31e71
	https://git.kernel.org/stable/c/0af718a690acc089aa1bbb95a93df833d864ef53
	https://git.kernel.org/stable/c/d85ca8179a54ff8cf1e1f8c3c9e3799831319bae
	https://git.kernel.org/stable/c/724e7965af054079242b8d6f7e50ee226730a756
	https://git.kernel.org/stable/c/2d090c7f7be3b26fcb80ac04d08a4a8062b1d959
	https://git.kernel.org/stable/c/be4e1304419c99a164b4c0e101c7c2a756b635b9