CVE-2026-74652: serial: amba-pl011: cancel RS485 hrtimers after freeing IRQ

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

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

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

serial: amba-pl011: cancel RS485 hrtimers after freeing IRQ

The RS485 trigger hrtimers are embedded in the devm-managed port and can
fire after it is freed. The IRQ handler can arm a timer, so free the IRQ
first and then cancel both timers.

Complete the RS485 stop without arming a timer, and cancel the timers
in remove() for the suspend-then-unbind path, where shutdown is not
called.

This issue was found by an in-house static analysis tool.

The Linux kernel CVE team has assigned CVE-2026-74652 to this issue.


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

	Issue introduced in 6.14 with commit 2c1fd53af21b8cb13878b054894d33d3383eb1f3 and fixed in 6.18.45 with commit 759ead98a39fb625be302f9aa66290985dcaa325
	Issue introduced in 6.14 with commit 2c1fd53af21b8cb13878b054894d33d3383eb1f3 and fixed in 7.1.9 with commit e57f0aa5c35be37218ba0e4887b241584dd4b2d2
	Issue introduced in 6.14 with commit 2c1fd53af21b8cb13878b054894d33d3383eb1f3 and fixed in 7.2 with commit 36672c8d7d14e9c43287528455d2c97b526ea6ad

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-2026-74652
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/tty/serial/amba-pl011.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/759ead98a39fb625be302f9aa66290985dcaa325
	https://git.kernel.org/stable/c/e57f0aa5c35be37218ba0e4887b241584dd4b2d2
	https://git.kernel.org/stable/c/36672c8d7d14e9c43287528455d2c97b526ea6ad