Subject: CVE-2023-52671: drm/amd/display: Fix hang/underflow when transitioning to ODM4:1

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

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

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

drm/amd/display: Fix hang/underflow when transitioning to ODM4:1

[Why]
Under some circumstances, disabling an OPTC and attempting to reclaim
its OPP(s) for a different OPTC could cause a hang/underflow due to OPPs
not being properly disconnected from the disabled OPTC.

[How]
Ensure that all OPPs are unassigned from an OPTC when it gets disabled.

The Linux kernel CVE team has assigned CVE-2023-52671 to this issue.

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

	Fixed in 6.6.24 with commit ae62f1dde66a
	Fixed in 6.7.3 with commit 4b6b479b2da6
	Fixed in 6.8 with commit e7b2b108cdea

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-2023-52671
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/optc/dcn32/dcn32_optc.c
	drivers/gpu/drm/amd/display/dc/optc/dcn35/dcn35_optc.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/ae62f1dde66a6f0eee98defc4c7a346bd5acd239
	https://git.kernel.org/stable/c/4b6b479b2da6badff099b2e3abf0248936eefbf5
	https://git.kernel.org/stable/c/e7b2b108cdeab76a7e7324459e50b0c1214c0386