Subject: CVE-2024-42091: drm/xe: Check pat.ops before dumping PAT settings

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

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

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

drm/xe: Check pat.ops before dumping PAT settings

We may leave pat.ops unset when running on brand new platform or
when running as a VF.  While the former is unlikely, the latter
is valid (future) use case and will cause NPD when someone will
try to dump PAT settings by debugfs.

It's better to check pointer to pat.ops instead of specific .dump
hook, as we have this hook always defined for every .ops variant.

The Linux kernel CVE team has assigned CVE-2024-42091 to this issue.

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

	Fixed in 6.9.8 with commit 583ce246c7ff
	Fixed in 6.10 with commit a918e771e6fb

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-2024-42091
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/xe/xe_pat.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/583ce246c7ff9edeb0de49130cdc3d45db8545cb
	https://git.kernel.org/stable/c/a918e771e6fbe1fa68932af5b0cdf473e23090cc