CVE-2026-68229: media: cedrus: skip invalid H.264 reference list entries

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

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

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

media: cedrus: skip invalid H.264 reference list entries

Cedrus consumes H.264 ref_pic_list0/ref_pic_list1 entries from the
stateless slice control and later uses their indices to look up
decode->dpb[] in _cedrus_write_ref_list().

Rejecting such controls in cedrus_try_ctrl() would break existing
userspace, since stateless H.264 reference lists may legitimately carry
out-of-range indices for missing references. Instead, guard the actual
DPB lookup in Cedrus and skip entries whose indices do not fit the fixed
V4L2_H264_NUM_DPB_ENTRIES array.

This keeps the fix local to the driver use site and avoids out-of-bounds
reads from malformed or unsupported reference list entries.

The Linux kernel CVE team has assigned CVE-2026-68229 to this issue.


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

	Issue introduced in 5.10 with commit e000e1fa4bdbd783149e7f97cf3be61e1c0bab8c and fixed in 6.6.148 with commit 2ee8327c85b3ac7b532d2d6a1e3a295d5ad7414a
	Issue introduced in 5.10 with commit e000e1fa4bdbd783149e7f97cf3be61e1c0bab8c and fixed in 6.12.101 with commit 0af8945fcae742d099f59f3c725eb67235953a31
	Issue introduced in 5.10 with commit e000e1fa4bdbd783149e7f97cf3be61e1c0bab8c and fixed in 6.18.42 with commit 9924cb548ee7753a6473997949c3ec48092de0b0
	Issue introduced in 5.10 with commit e000e1fa4bdbd783149e7f97cf3be61e1c0bab8c and fixed in 7.1.6 with commit e53112c2de88982e66c369aee2120d5efd78df30
	Issue introduced in 5.10 with commit e000e1fa4bdbd783149e7f97cf3be61e1c0bab8c and fixed in 7.2-rc1 with commit 10358ea986c3c85516d1c8206486464f79d36e76

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-2026-68229
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/staging/media/sunxi/cedrus/cedrus_h264.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/2ee8327c85b3ac7b532d2d6a1e3a295d5ad7414a
	https://git.kernel.org/stable/c/0af8945fcae742d099f59f3c725eb67235953a31
	https://git.kernel.org/stable/c/9924cb548ee7753a6473997949c3ec48092de0b0
	https://git.kernel.org/stable/c/e53112c2de88982e66c369aee2120d5efd78df30
	https://git.kernel.org/stable/c/10358ea986c3c85516d1c8206486464f79d36e76