cve/published/2025/CVE-2025-37891.mbox

From bippy-1.2.0 Mon Sep 17 00:00:00 2001
From: Greg Kroah-Hartman <gregkh@kernel.org>
To: <linux-cve-announce@vger.kernel.org>
Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org>
Subject: CVE-2025-37891: ALSA: ump: Fix buffer overflow at UMP SysEx message conversion

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

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

ALSA: ump: Fix buffer overflow at UMP SysEx message conversion

The conversion function from MIDI 1.0 to UMP packet contains an
internal buffer to keep the incoming MIDI bytes, and its size is 4, as
it was supposed to be the max size for a MIDI1 UMP packet data.
However, the implementation overlooked that SysEx is handled in a
different format, and it can be up to 6 bytes, as found in
do_convert_to_ump().  It leads eventually to a buffer overflow, and
may corrupt the memory when a longer SysEx message is received.

The fix is simply to extend the buffer size to 6 to fit with the SysEx
UMP message.

The Linux kernel CVE team has assigned CVE-2025-37891 to this issue.


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

	Issue introduced in 6.5 with commit 0b5288f5fe63eab687c14e5940b9e0d532b129f2 and fixed in 6.6.90 with commit ce4f77bef276e7d2eb7ab03a5d08bcbaa40710ec
	Issue introduced in 6.5 with commit 0b5288f5fe63eab687c14e5940b9e0d532b129f2 and fixed in 6.12.28 with commit 226beac5605afbb33f8782148d188b64396145a4
	Issue introduced in 6.5 with commit 0b5288f5fe63eab687c14e5940b9e0d532b129f2 and fixed in 6.14.6 with commit 42ef48dd4ebb082a1a90b5c3feeda2e68a9e32fe
	Issue introduced in 6.5 with commit 0b5288f5fe63eab687c14e5940b9e0d532b129f2 and fixed in 6.15 with commit 56f1f30e6795b890463d9b20b11e576adf5a2f77

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-2025-37891
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:
	include/sound/ump_convert.h


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/ce4f77bef276e7d2eb7ab03a5d08bcbaa40710ec
	https://git.kernel.org/stable/c/226beac5605afbb33f8782148d188b64396145a4
	https://git.kernel.org/stable/c/42ef48dd4ebb082a1a90b5c3feeda2e68a9e32fe
	https://git.kernel.org/stable/c/56f1f30e6795b890463d9b20b11e576adf5a2f77