CVE-2024-26914: drm/amd/display: fix incorrect mpc_combine array size

CVE-2024-26914: drm/amd/display: fix incorrect mpc_combine array size

[Greg Kroah-Hartman]

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

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

drm/amd/display: fix incorrect mpc_combine array size

[why]
MAX_SURFACES is per stream, while MAX_PLANES is per asic. The
mpc_combine is an array that records all the planes per asic. Therefore
MAX_PLANES should be used as the array size. Using MAX_SURFACES causes
array overflow when there are more than 3 planes.

[how]
Use the MAX_PLANES for the mpc_combine array size.

The Linux kernel CVE team has assigned CVE-2024-26914 to this issue.


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

	Fixed in 6.7.6 with commit 0bd8ef618a42
	Fixed in 6.8 with commit 39079fe8e660

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-2024-26914
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/dml/dcn32/dcn32_fpu.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/0bd8ef618a42d7e6ea3f701065264e15678025e3
	https://git.kernel.org/stable/c/39079fe8e660851abbafa90cd55cbf029210661f