CVE-2026-74345: RDMA/siw: Fix endpoint/socket association handling

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

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

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

RDMA/siw: Fix endpoint/socket association handling

Disassociating a socket from an endpoint via siw_socket_disassoc() may
release the last reference on that endpoint and free it. Therefore, don't
clear the endpoints socket pointer after calling that function, but
within.

This fixes a:

  BUG: KASAN: slab-use-after-free in siw_cm_work_handler (drivers/infiniband/sw/siw/siw_cm.c:1053 drivers/infiniband/sw/siw/siw_cm.c:1075)

which occurred after processing a malformed MPA request during connection
establishment, causing the new endpoint to be closed.

The Linux kernel CVE team has assigned CVE-2026-74345 to this issue.


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

	Issue introduced in 5.3 with commit 6c52fdc244b5ccc468006fd65a504d4ee33743c7 and fixed in 6.12.97 with commit b28d513393f81e2de00f82970487a9d001557e4e
	Issue introduced in 5.3 with commit 6c52fdc244b5ccc468006fd65a504d4ee33743c7 and fixed in 6.18.40 with commit f6183983ce1ff254d629a333739082b39d7c5eb6
	Issue introduced in 5.3 with commit 6c52fdc244b5ccc468006fd65a504d4ee33743c7 and fixed in 7.1.5 with commit b6cf763eee0a932792bef64ceaca568d324192fc
	Issue introduced in 5.3 with commit 6c52fdc244b5ccc468006fd65a504d4ee33743c7 and fixed in 7.2-rc1 with commit ea4f6f6c53577fb3f05dbd78b15e586772d49831

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-2026-74345
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/infiniband/sw/siw/siw_cm.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/b28d513393f81e2de00f82970487a9d001557e4e
	https://git.kernel.org/stable/c/f6183983ce1ff254d629a333739082b39d7c5eb6
	https://git.kernel.org/stable/c/b6cf763eee0a932792bef64ceaca568d324192fc
	https://git.kernel.org/stable/c/ea4f6f6c53577fb3f05dbd78b15e586772d49831