Subject: CVE-2024-50044: Bluetooth: RFCOMM: FIX possible deadlock in rfcomm_sk_state_change

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

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

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

Bluetooth: RFCOMM: FIX possible deadlock in rfcomm_sk_state_change

rfcomm_sk_state_change attempts to use sock_lock so it must never be
called with it locked but rfcomm_sock_ioctl always attempt to lock it
causing the following trace:

======================================================
WARNING: possible circular locking dependency detected
6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted
------------------------------------------------------
syz-executor386/5093 is trying to acquire lock:
ffff88807c396258 (sk_lock-AF_BLUETOOTH-BTPROTO_RFCOMM){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1671 [inline]
ffff88807c396258 (sk_lock-AF_BLUETOOTH-BTPROTO_RFCOMM){+.+.}-{0:0}, at: rfcomm_sk_state_change+0x5b/0x310 net/bluetooth/rfcomm/sock.c:73

but task is already holding lock:
ffff88807badfd28 (&d->lock){+.+.}-{3:3}, at: __rfcomm_dlc_close+0x226/0x6a0 net/bluetooth/rfcomm/core.c:491

The Linux kernel CVE team has assigned CVE-2024-50044 to this issue.

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

	Issue introduced in 2.6.27 with commit 3241ad820dbb and fixed in 5.10.227 with commit ef44274dae9b
	Issue introduced in 2.6.27 with commit 3241ad820dbb and fixed in 5.15.168 with commit 496b2ab0fd10
	Issue introduced in 2.6.27 with commit 3241ad820dbb and fixed in 6.1.113 with commit ced98072d351
	Issue introduced in 2.6.27 with commit 3241ad820dbb and fixed in 6.6.57 with commit 38b2d5a57d12
	Issue introduced in 2.6.27 with commit 3241ad820dbb and fixed in 6.11.4 with commit 4cb9807c9b53
	Issue introduced in 2.6.27 with commit 3241ad820dbb and fixed in 6.12-rc3 with commit 08d1914293da

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-2024-50044
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/ef44274dae9b0a90d1a97ce8b242a3b8243a7745
	https://git.kernel.org/stable/c/496b2ab0fd10f205e08909a125485fdc98843dbe
	https://git.kernel.org/stable/c/ced98072d3511b232ae1d3347945f35f30c0e303
	https://git.kernel.org/stable/c/38b2d5a57d125e1c17661b8308c0240c4a43b534
	https://git.kernel.org/stable/c/4cb9807c9b53bf1e5560420d26f319f528b50268
	https://git.kernel.org/stable/c/08d1914293dae38350b8088980e59fbc699a72fe