Subject: CVE-2024-35966: Bluetooth: RFCOMM: Fix not validating setsockopt user input

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

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

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

Bluetooth: RFCOMM: Fix not validating setsockopt user input

syzbot reported rfcomm_sock_setsockopt_old() is copying data without
checking user input length.

BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset
include/linux/sockptr.h:49 [inline]
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr
include/linux/sockptr.h:55 [inline]
BUG: KASAN: slab-out-of-bounds in rfcomm_sock_setsockopt_old
net/bluetooth/rfcomm/sock.c:632 [inline]
BUG: KASAN: slab-out-of-bounds in rfcomm_sock_setsockopt+0x893/0xa70
net/bluetooth/rfcomm/sock.c:673
Read of size 4 at addr ffff8880209a8bc3 by task syz-executor632/5064

The Linux kernel CVE team has assigned CVE-2024-35966 to this issue.

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

	Issue introduced in 2.6.30 with commit 9f2c8a03fbb3 and fixed in 6.1.107 with commit eea40d33bf93
	Issue introduced in 2.6.30 with commit 9f2c8a03fbb3 and fixed in 6.6.47 with commit 4ea65e2095e9
	Issue introduced in 2.6.30 with commit 9f2c8a03fbb3 and fixed in 6.8.7 with commit c3f787a3eafe
	Issue introduced in 2.6.30 with commit 9f2c8a03fbb3 and fixed in 6.9 with commit a97de7bff13b

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-2024-35966
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/bluetooth/rfcomm/sock.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/eea40d33bf936a5c7fb03c190e61e0cfee00e872
	https://git.kernel.org/stable/c/4ea65e2095e9bd151d0469328dd7fc2858feb546
	https://git.kernel.org/stable/c/c3f787a3eafe519c93df9abbb0ca5145861c8d0f
	https://git.kernel.org/stable/c/a97de7bff13b1cc825c1b1344eaed8d6c2d3e695