CVE-2026-89734: usb: gadget: uvc: Fix null pointer dereference in uvcg_video_init()

CVE-2026-89734: usb: gadget: uvc: Fix null pointer dereference in uvcg_video_init()

[Greg Kroah-Hartman]

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

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

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

usb: gadget: uvc: Fix null pointer dereference in uvcg_video_init()

In uvcg_video_init(), if kthread_run_worker() fails,
the error logged uses uvcg_err(), however, the pointer it uses:
video->uvc is not assigned at this point, triggering a null
pointer dereference. Fix this by directly using uvc->func which
is assigned already.

The Linux kernel CVE team has assigned CVE-2026-89734 to this issue.


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

	Issue introduced in 6.13 with commit f0bbfbd16b3b67106535299d6a9ca3a5565494a6 and fixed in 6.18.50 with commit dbe2762ae8e543b06c57f1ac6512b02fd3fd09b2
	Issue introduced in 6.13 with commit f0bbfbd16b3b67106535299d6a9ca3a5565494a6 and fixed in 7.2.4 with commit d511e015d06767f52bb18d48371cab6d7cb88433
	Issue introduced in 6.13 with commit f0bbfbd16b3b67106535299d6a9ca3a5565494a6 and fixed in 7.3-rc1 with commit 5b1da38592efdc1a263d4c0353298cba19e9d6fc

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-2026-89734
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/usb/gadget/function/uvc_video.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/dbe2762ae8e543b06c57f1ac6512b02fd3fd09b2
	https://git.kernel.org/stable/c/d511e015d06767f52bb18d48371cab6d7cb88433
	https://git.kernel.org/stable/c/5b1da38592efdc1a263d4c0353298cba19e9d6fc