Subject: CVE-2024-27063: leds: trigger: netdev: Fix kernel panic on interface rename trig notify

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

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

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

leds: trigger: netdev: Fix kernel panic on interface rename trig notify

Commit d5e01266e7f5 ("leds: trigger: netdev: add additional specific link
speed mode") in the various changes, reworked the way to set the LINKUP
mode in commit cee4bd16c319 ("leds: trigger: netdev: Recheck
NETDEV_LED_MODE_LINKUP on dev rename") and moved it to a generic function.

This changed the logic where, in the previous implementation the dev
from the trigger event was used to check if the carrier was ok, but in
the new implementation with the generic function, the dev in
trigger_data is used instead.

This is problematic and cause a possible kernel panic due to the fact
that the dev in the trigger_data still reference the old one as the
new one (passed from the trigger event) still has to be hold and saved
in the trigger_data struct (done in the NETDEV_REGISTER case).

On calling of get_device_state(), an invalid net_dev is used and this
cause a kernel panic.

To handle this correctly, move the call to get_device_state() after the
new net_dev is correctly set in trigger_data (in the NETDEV_REGISTER
case) and correctly parse the new dev.

The Linux kernel CVE team has assigned CVE-2024-27063 to this issue.

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

	Issue introduced in 6.5 with commit d5e01266e7f5 and fixed in 6.6.24 with commit 10f2af1af8ab
	Issue introduced in 6.5 with commit d5e01266e7f5 and fixed in 6.7.12 with commit acd025c7a7d1
	Issue introduced in 6.5 with commit d5e01266e7f5 and fixed in 6.8.3 with commit 3f360227cb46
	Issue introduced in 6.5 with commit d5e01266e7f5 and fixed in 6.9 with commit 415798bc07dd

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-2024-27063
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/leds/trigger/ledtrig-netdev.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/10f2af1af8ab8a7064f193446abd5579d3def7e3
	https://git.kernel.org/stable/c/acd025c7a7d151261533016a6ca2d38f2de04e87
	https://git.kernel.org/stable/c/3f360227cb46edb2cd2494128e1e06ed5768a62e
	https://git.kernel.org/stable/c/415798bc07dd1c1ae3a656aa026580816e0b9fe8