CVE-2026-97567: mptcp: prevent race between disconnect() and rtx

CVE-2026-97567: mptcp: prevent race between disconnect() and rtx

[Greg Kroah-Hartman]

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

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

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

mptcp: prevent race between disconnect() and rtx

Sashiko noted that the two event can race, leading to inconsistent
status. Prevent the race using the synchronous timer stop operation.

The Linux kernel CVE team has assigned CVE-2026-97567 to this issue.


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

	Issue introduced in 5.17 with commit b29fcfb54cd70caca5b11c80d8d238854938884a and fixed in 6.18.53 with commit 374da2b9be1280695ce41f108334a8f16e3e54be
	Issue introduced in 5.17 with commit b29fcfb54cd70caca5b11c80d8d238854938884a and fixed in 7.2.7 with commit 69a7b2a912672159dda7dcf325d27752d448dfdf
	Issue introduced in 5.17 with commit b29fcfb54cd70caca5b11c80d8d238854938884a and fixed in 7.3-rc3 with commit 85c580b0d8590520ae00a15c29e9fb9c99427a3e

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-2026-97567
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:
	net/mptcp/protocol.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/374da2b9be1280695ce41f108334a8f16e3e54be
	https://git.kernel.org/stable/c/69a7b2a912672159dda7dcf325d27752d448dfdf
	https://git.kernel.org/stable/c/85c580b0d8590520ae00a15c29e9fb9c99427a3e