CVE-2026-68225: media: i2c: alvium: fix critical pointer access in alvium_ctrl_init

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

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

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

media: i2c: alvium: fix critical pointer access in alvium_ctrl_init

The current implementation of alvium_ctrl_init creates several controls in
function alvium_ctrl_init and uses the returned pointer without check. That
can cause write access over NULL-pointer for several controls. The reworked
code checks the pointers before adding flags.

The Linux kernel CVE team has assigned CVE-2026-68225 to this issue.


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

	Issue introduced in 6.8 with commit 0a7af872915ee34668edf7e4018648a226d9e7f9 and fixed in 6.12.101 with commit 4bacfda44d36f165f6cb57bea408912886400ffa
	Issue introduced in 6.8 with commit 0a7af872915ee34668edf7e4018648a226d9e7f9 and fixed in 6.18.42 with commit 7337c88205ed0ffc654f40266be0d3c3eb15fb29
	Issue introduced in 6.8 with commit 0a7af872915ee34668edf7e4018648a226d9e7f9 and fixed in 7.1.6 with commit eb2f934646aefb06314cecd1deb020794829b207
	Issue introduced in 6.8 with commit 0a7af872915ee34668edf7e4018648a226d9e7f9 and fixed in 7.2-rc1 with commit 4f6f28ff24709710c08557c127b3e4c3fb1b4159

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-2026-68225
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/i2c/alvium-csi2.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/4bacfda44d36f165f6cb57bea408912886400ffa
	https://git.kernel.org/stable/c/7337c88205ed0ffc654f40266be0d3c3eb15fb29
	https://git.kernel.org/stable/c/eb2f934646aefb06314cecd1deb020794829b207
	https://git.kernel.org/stable/c/4f6f28ff24709710c08557c127b3e4c3fb1b4159