CVE-2026-72109: net: sparx5: unregister blocking notifier on init failure

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

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

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

net: sparx5: unregister blocking notifier on init failure

sparx5_register_notifier_blocks() registers the switchdev blocking
notifier before allocating the ordered workqueue. If the workqueue
allocation fails, the error path unregisters the switchdev and netdevice
notifiers, but leaves the blocking notifier registered.

Add a separate error label for the workqueue allocation failure path and
unregister the switchdev blocking notifier there.

The Linux kernel CVE team has assigned CVE-2026-72109 to this issue.


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

	Issue introduced in 5.14 with commit d6fce5141929697a27f029c633433d487f6f62cb and fixed in 5.15.212 with commit fbc65b17508ed5464b7106e7fa5f15251ca1b603
	Issue introduced in 5.14 with commit d6fce5141929697a27f029c633433d487f6f62cb and fixed in 6.1.178 with commit e5afc6d3fabdf1f605d63c4b34a3df6c359e81f3
	Issue introduced in 5.14 with commit d6fce5141929697a27f029c633433d487f6f62cb and fixed in 6.6.145 with commit cf419c869e0d03aad4b6f4ecf0a813851930dfe7
	Issue introduced in 5.14 with commit d6fce5141929697a27f029c633433d487f6f62cb and fixed in 6.12.97 with commit d6084c47389fd6978a5d66b0d58206a548c792a9
	Issue introduced in 5.14 with commit d6fce5141929697a27f029c633433d487f6f62cb and fixed in 6.18.40 with commit 8a3c44a003176282ee4306b7c96e5a536c6f0707
	Issue introduced in 5.14 with commit d6fce5141929697a27f029c633433d487f6f62cb and fixed in 7.1.5 with commit 17f113e7b622dc850992ade540181717de6a8561
	Issue introduced in 5.14 with commit d6fce5141929697a27f029c633433d487f6f62cb and fixed in 7.2-rc1 with commit 483be61b4a9a6df3b7cb277e8f189e082dee4cb8

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-2026-72109
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/ethernet/microchip/sparx5/sparx5_switchdev.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/fbc65b17508ed5464b7106e7fa5f15251ca1b603
	https://git.kernel.org/stable/c/e5afc6d3fabdf1f605d63c4b34a3df6c359e81f3
	https://git.kernel.org/stable/c/cf419c869e0d03aad4b6f4ecf0a813851930dfe7
	https://git.kernel.org/stable/c/d6084c47389fd6978a5d66b0d58206a548c792a9
	https://git.kernel.org/stable/c/8a3c44a003176282ee4306b7c96e5a536c6f0707
	https://git.kernel.org/stable/c/17f113e7b622dc850992ade540181717de6a8561
	https://git.kernel.org/stable/c/483be61b4a9a6df3b7cb277e8f189e082dee4cb8