CVE-2026-97575: media: v4l2-ctrls: validate AV1 tile counts

CVE-2026-97575: media: v4l2-ctrls: validate AV1 tile counts

[Greg Kroah-Hartman]

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

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

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

media: v4l2-ctrls: validate AV1 tile counts

The stateless AV1 decoders use tile_info.tile_cols and tile_rows as loop
bounds and as indices into the mi_*_starts[] and *_in_sbs_minus_1[]
arrays, as the divisor for context_update_tile_id, and their product
bounds the per-tile descriptor buffers, but std_validate_compound() does
not bound these u8 fields. Reject a V4L2_CTRL_TYPE_AV1_FRAME whose
tile_cols or tile_rows exceeds V4L2_AV1_MAX_TILE_COLS / _ROWS, or whose
product exceeds V4L2_AV1_MAX_TILE_COUNT. A zero tile count is left to the
consuming driver so the zero-initialised control that existing userspace
submits is still accepted.

The Linux kernel CVE team has assigned CVE-2026-97575 to this issue.


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

	Issue introduced in 6.5 with commit 9de30f579980b498606a9c2440b73ae3b670771b and fixed in 6.12.111 with commit 85df9fc79b07f1cc7c953f930ae7e675d0c1e820
	Issue introduced in 6.5 with commit 9de30f579980b498606a9c2440b73ae3b670771b and fixed in 6.18.53 with commit c8891da0186fe4c04bccbbd7d84b01a3c941ac7a
	Issue introduced in 6.5 with commit 9de30f579980b498606a9c2440b73ae3b670771b and fixed in 7.2.7 with commit c4c88b5ba85685043d171e0e9c9d00a8cf6a89e8
	Issue introduced in 6.5 with commit 9de30f579980b498606a9c2440b73ae3b670771b and fixed in 7.3-rc3 with commit 439058ced617fbb3febc017b9e93bb7387f309e0

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-2026-97575
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/media/v4l2-core/v4l2-ctrls-core.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/85df9fc79b07f1cc7c953f930ae7e675d0c1e820
	https://git.kernel.org/stable/c/c8891da0186fe4c04bccbbd7d84b01a3c941ac7a
	https://git.kernel.org/stable/c/c4c88b5ba85685043d171e0e9c9d00a8cf6a89e8
	https://git.kernel.org/stable/c/439058ced617fbb3febc017b9e93bb7387f309e0