CVE-2026-64337: usb: mtu3: unmap request DMA on queue failure

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

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

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

usb: mtu3: unmap request DMA on queue failure

mtu3_gadget_queue() maps the request before checking whether
the QMU GPD ring can accept another transfer. the request is
returned with -EAGAIN before it is linked on the endpoint
request list if mtu3_prepare_transfer() fails.

Normal completion and dequeue paths unmap requests from
mtu3_req_complete(), but this error path never reaches that
helper, so the DMA mapping is left active. Unmap the request
before returning from the failed queue path.

The Linux kernel CVE team has assigned CVE-2026-64337 to this issue.


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

	Issue introduced in 4.10 with commit df2069acb00569a6299d6e11aa1865eeba463848 and fixed in 5.10.261 with commit 3cee30f1138281a1d247bb053a1ad4f7c5b04e98
	Issue introduced in 4.10 with commit df2069acb00569a6299d6e11aa1865eeba463848 and fixed in 5.15.212 with commit f3c4026524d3660c73ef2838b99776d37631e039
	Issue introduced in 4.10 with commit df2069acb00569a6299d6e11aa1865eeba463848 and fixed in 6.1.178 with commit e8f739a3860d043dcc135371637e82f53132efe5
	Issue introduced in 4.10 with commit df2069acb00569a6299d6e11aa1865eeba463848 and fixed in 6.6.145 with commit 4183874b7925f4a98b400cf857bea26ee87da236
	Issue introduced in 4.10 with commit df2069acb00569a6299d6e11aa1865eeba463848 and fixed in 6.12.96 with commit 00c3fef4c2dc2c7cbd8281f8fda09d1913420f09
	Issue introduced in 4.10 with commit df2069acb00569a6299d6e11aa1865eeba463848 and fixed in 6.18.39 with commit 8c29d9cfab1c3cf0d0b7fcdf9255597be30aa3e1
	Issue introduced in 4.10 with commit df2069acb00569a6299d6e11aa1865eeba463848 and fixed in 7.1.4 with commit 835b0596d4c9bdef93f842d8f826978fb4956b74
	Issue introduced in 4.10 with commit df2069acb00569a6299d6e11aa1865eeba463848 and fixed in 7.2-rc3 with commit 0bddda5a11665c210339de76d27ebbd1a2e0b43c

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-2026-64337
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/mtu3/mtu3_gadget.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/3cee30f1138281a1d247bb053a1ad4f7c5b04e98
	https://git.kernel.org/stable/c/f3c4026524d3660c73ef2838b99776d37631e039
	https://git.kernel.org/stable/c/e8f739a3860d043dcc135371637e82f53132efe5
	https://git.kernel.org/stable/c/4183874b7925f4a98b400cf857bea26ee87da236
	https://git.kernel.org/stable/c/00c3fef4c2dc2c7cbd8281f8fda09d1913420f09
	https://git.kernel.org/stable/c/8c29d9cfab1c3cf0d0b7fcdf9255597be30aa3e1
	https://git.kernel.org/stable/c/835b0596d4c9bdef93f842d8f826978fb4956b74
	https://git.kernel.org/stable/c/0bddda5a11665c210339de76d27ebbd1a2e0b43c