CVE-2026-43372: net: dsa: microchip: Fix error path in PTP IRQ setup

CVE-2026-43372: net: dsa: microchip: Fix error path in PTP IRQ setup

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

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

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

net: dsa: microchip: Fix error path in PTP IRQ setup

If request_threaded_irq() fails during the PTP message IRQ setup, the
newly created IRQ mapping is never disposed. Indeed, the
ksz_ptp_irq_setup()'s error path only frees the mappings that were
successfully set up.

Dispose the newly created mapping if the associated
request_threaded_irq() fails at setup.

The Linux kernel CVE team has assigned CVE-2026-43372 to this issue.


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

	Issue introduced in 6.6.119 with commit 3b5a6115d6ea45df1ea65dc9b832b23db5d593ba and fixed in 6.6.130 with commit 3704ac6a0d9a78f66a187515a8ca3faedaf01cc5
	Issue introduced in 6.12.61 with commit 1ba6da6ca3db76f6a39004fd33a9c990e428515e and fixed in 6.12.78 with commit e80fef36c676c947072dabeb5803ae59d92ba493
	Issue introduced in 6.18 with commit d0b8fec8ae50525b57139393d0bb1f446e82ff7e and fixed in 6.18.19 with commit 6c58a9fdb0d0e1011aa02455d26d6ebea251979b
	Issue introduced in 6.18 with commit d0b8fec8ae50525b57139393d0bb1f446e82ff7e and fixed in 6.19.9 with commit c2d1d41e0e8ec447d40a5752844fc5fb0b23db27
	Issue introduced in 6.18 with commit d0b8fec8ae50525b57139393d0bb1f446e82ff7e and fixed in 7.0 with commit 99c8c16a4aad0b37293cae213e15957c573cf79b
	Issue introduced in 6.17.11 with commit ae12e4e0ca231475bcef841c6a6722fa185fd520

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-2026-43372
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/dsa/microchip/ksz_ptp.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/3704ac6a0d9a78f66a187515a8ca3faedaf01cc5
	https://git.kernel.org/stable/c/e80fef36c676c947072dabeb5803ae59d92ba493
	https://git.kernel.org/stable/c/6c58a9fdb0d0e1011aa02455d26d6ebea251979b
	https://git.kernel.org/stable/c/c2d1d41e0e8ec447d40a5752844fc5fb0b23db27
	https://git.kernel.org/stable/c/99c8c16a4aad0b37293cae213e15957c573cf79b