Subject: CVE-2024-49906: drm/amd/display: Check null pointer before try to access it

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

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

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

drm/amd/display: Check null pointer before try to access it

[why & how]
Change the order of the pipe_ctx->plane_state check to ensure that
plane_state is not null before accessing it.

The Linux kernel CVE team has assigned CVE-2024-49906 to this issue.

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

	Fixed in 6.11.3 with commit 2002ccb93004
	Fixed in 6.12-rc1 with commit 1b686053c06f

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-2024-49906
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/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.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/2002ccb93004e76a471b180560accb2c1f850f35
	https://git.kernel.org/stable/c/1b686053c06ffb9f4524b288110cf2a831ff7a25