CVE-2024-47408: net/smc: check smcd_v2_ext_offset when receiving proposal msg

CVE-2024-47408: net/smc: check smcd_v2_ext_offset when receiving proposal msg

[Greg Kroah-Hartman]

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

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

net/smc: check smcd_v2_ext_offset when receiving proposal msg

When receiving proposal msg in server, the field smcd_v2_ext_offset in
proposal msg is from the remote client and can not be fully trusted.
Once the value of smcd_v2_ext_offset exceed the max value, there has
the chance to access wrong address, and crash may happen.

This patch checks the value of smcd_v2_ext_offset before using it.

The Linux kernel CVE team has assigned CVE-2024-47408 to this issue.


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

	Issue introduced in 5.10 with commit 5c21c4ccafe85906db809de3af391fd434df8a27 and fixed in 5.15.176 with commit a36364d8d4fabb105001f992fb8ff2d3546203d6
	Issue introduced in 5.10 with commit 5c21c4ccafe85906db809de3af391fd434df8a27 and fixed in 6.1.122 with commit e1cc8be2a785a8f1ce1f597f3e608602c5fccd46
	Issue introduced in 5.10 with commit 5c21c4ccafe85906db809de3af391fd434df8a27 and fixed in 6.6.68 with commit 935caf324b445fe73d7708fae6f7176fb243f357
	Issue introduced in 5.10 with commit 5c21c4ccafe85906db809de3af391fd434df8a27 and fixed in 6.12.7 with commit 48d5a8a304a643613dab376a278f29d3e22f7c34
	Issue introduced in 5.10 with commit 5c21c4ccafe85906db809de3af391fd434df8a27 and fixed in 6.13-rc4 with commit 9ab332deb671d8f7e66d82a2ff2b3f715bc3a4ad

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-2024-47408
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/smc/af_smc.c
	net/smc/smc_clc.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/a36364d8d4fabb105001f992fb8ff2d3546203d6
	https://git.kernel.org/stable/c/e1cc8be2a785a8f1ce1f597f3e608602c5fccd46
	https://git.kernel.org/stable/c/935caf324b445fe73d7708fae6f7176fb243f357
	https://git.kernel.org/stable/c/48d5a8a304a643613dab376a278f29d3e22f7c34
	https://git.kernel.org/stable/c/9ab332deb671d8f7e66d82a2ff2b3f715bc3a4ad