CVE-2026-68254: drm/i915/vrr: require valid min/max vfreq for VRR

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

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

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

drm/i915/vrr: require valid min/max vfreq for VRR

Ensure the EDID provided min/max vfreq are valid. Most scenarios are
already covered (by coincidence) through the checks in
intel_vrr_is_capable() and intel_vrr_is_in_range(), but be more explicit
about it. At worst, a zero min_vfreq could lead to a division by zero in
intel_vrr_compute_vmax().

Discovered using AI-assisted static analysis confirmed by Intel Product
Security.

(cherry picked from commit 1765cf59f517b02f3b0591fe5120930d08bddeb6)

The Linux kernel CVE team has assigned CVE-2026-68254 to this issue.


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

	Issue introduced in 5.12 with commit 117cd09ba52857a60dc5d7f61941046625d8ff5a and fixed in 6.6.151 with commit 6598ac1721c3a5543efdbcab579a8561268d7ce1
	Issue introduced in 5.12 with commit 117cd09ba52857a60dc5d7f61941046625d8ff5a and fixed in 6.12.103 with commit f16218689b41efcbc491207cd7716477b1223879
	Issue introduced in 5.12 with commit 117cd09ba52857a60dc5d7f61941046625d8ff5a and fixed in 6.18.44 with commit df1582c0a101e2e2f133dd331d2a3258bb6a7518
	Issue introduced in 5.12 with commit 117cd09ba52857a60dc5d7f61941046625d8ff5a and fixed in 7.1.6 with commit c726c8bbee5115dad37fa7867136ebaa50690331
	Issue introduced in 5.12 with commit 117cd09ba52857a60dc5d7f61941046625d8ff5a and fixed in 7.2-rc2 with commit f8a9262c7a6fc2de9802e14b0228114f0333869e

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-2026-68254
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/i915/display/intel_vrr.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/6598ac1721c3a5543efdbcab579a8561268d7ce1
	https://git.kernel.org/stable/c/f16218689b41efcbc491207cd7716477b1223879
	https://git.kernel.org/stable/c/df1582c0a101e2e2f133dd331d2a3258bb6a7518
	https://git.kernel.org/stable/c/c726c8bbee5115dad37fa7867136ebaa50690331
	https://git.kernel.org/stable/c/f8a9262c7a6fc2de9802e14b0228114f0333869e