linux-cve-announce - CVE-2023-54038: Bluetooth: hci_conn: return ERR_PTR instead of NULL when there is no link

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [day] [month] [year] [list]

Message-ID: <2025122439-CVE-2023-54038-41bb@gregkh>
Date: Wed, 24 Dec 2025 11:57:22 +0100
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2023-54038: Bluetooth: hci_conn: return ERR_PTR instead of NULL when there is no link

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

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

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

Bluetooth: hci_conn: return ERR_PTR instead of NULL when there is no link

hci_connect_sco currently returns NULL when there is no link (i.e. when
hci_conn_link() returns NULL).

sco_connect() expects an ERR_PTR in case of any error (see line 266 in
sco.c). Thus, hcon set as NULL passes through to sco_conn_add(), which
tries to get hcon->hdev, resulting in dereferencing a NULL pointer as
reported by syzkaller.

The same issue exists for iso_connect_cis() calling hci_connect_cis().

Thus, make hci_connect_sco() and hci_connect_cis() return ERR_PTR
instead of NULL.

The Linux kernel CVE team has assigned CVE-2023-54038 to this issue.


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

	Issue introduced in 6.4 with commit 06149746e7203d5ffe2d6faf9799ee36203aa8b8 and fixed in 6.4.7 with commit 357ab53c83a5322437fa434e9a9e3e0bafe6b383
	Issue introduced in 6.4 with commit 06149746e7203d5ffe2d6faf9799ee36203aa8b8 and fixed in 6.5 with commit b4066eb04bb67e7ff66e5aaab0db4a753f37eaad
	Issue introduced in 6.3.8 with commit f72fc94a17d45be98aecfd59c39b5b24a6a342e2

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-2023-54038
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/hci_conn.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/357ab53c83a5322437fa434e9a9e3e0bafe6b383
	https://git.kernel.org/stable/c/b4066eb04bb67e7ff66e5aaab0db4a753f37eaad