CVE-2026-64521: pinctrl: meson: amlogic-a4: fix deadlock issue

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

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

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

pinctrl: meson: amlogic-a4: fix deadlock issue

Accessing the pinconf-pins sysfs node may deadlock.

pinconf_pins_show() holds pctldev->mutex, and the platform driver
calls pinctrl_find_gpio_range_from_pin(), which tries to acquire
the same mutex again, leading to a deadlock.

Use pinctrl_find_gpio_range_from_pin_nolock() to fix this issue.

The Linux kernel CVE team has assigned CVE-2026-64521 to this issue.


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

	Issue introduced in 6.15 with commit 6e9be3abb78c2f6c97a51070004a5165702f0ed9 and fixed in 6.18.34 with commit e917713f013423069782ff554935c7a5d4266783
	Issue introduced in 6.15 with commit 6e9be3abb78c2f6c97a51070004a5165702f0ed9 and fixed in 7.0.11 with commit 744ac926c0e55267a10b49b5b72582afef4ad49f
	Issue introduced in 6.15 with commit 6e9be3abb78c2f6c97a51070004a5165702f0ed9 and fixed in 7.1 with commit e72ce029810390eb987a036fb2c8a5da9a23b685

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-2026-64521
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/pinctrl/meson/pinctrl-amlogic-a4.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/e917713f013423069782ff554935c7a5d4266783
	https://git.kernel.org/stable/c/744ac926c0e55267a10b49b5b72582afef4ad49f
	https://git.kernel.org/stable/c/e72ce029810390eb987a036fb2c8a5da9a23b685