CVE-2026-72360: drm/xe/pf: Don't attempt to process FAST_REQ or EVENT relays

CVE-2026-72360: drm/xe/pf: Don't attempt to process FAST_REQ or EVENT relays

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

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

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

drm/xe/pf: Don't attempt to process FAST_REQ or EVENT relays

Currently defined VF/PF relay actions use regular REQUEST messages
only and the PF shouldn't attempt to handle FAST_REQUEST nor EVENT
messages as this would result in breaking the VFPF ABI protocol
and also might trigger an assert on the PF side.

(cherry picked from commit 1714d360fc5ae2e0886a69e979095d9c7ff3568a)

The Linux kernel CVE team has assigned CVE-2026-72360 to this issue.


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

	Issue introduced in 6.11 with commit 98e62805921cebcd2fcac3692037ca2ebef63b4a and fixed in 6.12.97 with commit 499be4b5d64209e9f18c9442f9fbeef7155ae900
	Issue introduced in 6.11 with commit 98e62805921cebcd2fcac3692037ca2ebef63b4a and fixed in 6.18.40 with commit adc7dda728ca3e340a413e3bbc10cf159e1866a4
	Issue introduced in 6.11 with commit 98e62805921cebcd2fcac3692037ca2ebef63b4a and fixed in 7.1.5 with commit a4208d8032abd7f591581994f31e23b80b8fe659
	Issue introduced in 6.11 with commit 98e62805921cebcd2fcac3692037ca2ebef63b4a and fixed in 7.2-rc2 with commit ed8b0d731892c68b41ecbd27c952af284816dec1

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-2026-72360
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_guc_relay.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/499be4b5d64209e9f18c9442f9fbeef7155ae900
	https://git.kernel.org/stable/c/adc7dda728ca3e340a413e3bbc10cf159e1866a4
	https://git.kernel.org/stable/c/a4208d8032abd7f591581994f31e23b80b8fe659
	https://git.kernel.org/stable/c/ed8b0d731892c68b41ecbd27c952af284816dec1