Subject: CVE-2024-35945: net: phy: phy_device: Prevent nullptr exceptions on ISR

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

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

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

net: phy: phy_device: Prevent nullptr exceptions on ISR

If phydev->irq is set unconditionally, check
for valid interrupt handler or fall back to polling mode to prevent
nullptr exceptions in interrupt service routine.

The Linux kernel CVE team has assigned CVE-2024-35945 to this issue.

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

	Fixed in 6.6.27 with commit 7a71f61ebf95
	Fixed in 6.8.6 with commit 3419ee39e3d3
	Fixed in 6.9 with commit 61c81872815f

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-2024-35945
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/phy/phy_device.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/7a71f61ebf95cedd3f245db6da397822971d8db5
	https://git.kernel.org/stable/c/3419ee39e3d3162ab2ec9942bb537613ed5b6311
	https://git.kernel.org/stable/c/61c81872815f46006982bb80460c0c80a949b35b