linux-cve-announce - CVE-2023-53292: blk-mq: fix NULL dereference on q->elevator in blk_mq_elv_switch

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: <2025091626-CVE-2023-53292-24e9@gregkh>
Date: Tue, 16 Sep 2025 10:11:42 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2023-53292: blk-mq: fix NULL dereference on q->elevator in blk_mq_elv_switch_none

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

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

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

blk-mq: fix NULL dereference on q->elevator in blk_mq_elv_switch_none

After grabbing q->sysfs_lock, q->elevator may become NULL because of
elevator switch.

Fix the NULL dereference on q->elevator by checking it with lock.

The Linux kernel CVE team has assigned CVE-2023-53292 to this issue.


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

	Fixed in 6.4.7 with commit 3e977386521b71471e66ec2ba82efdfcc456adf2
	Fixed in 6.5 with commit 245165658e1c9f95c0fecfe02b9b1ebd30a1198a

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-2023-53292
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:
	block/blk-mq.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/3e977386521b71471e66ec2ba82efdfcc456adf2
	https://git.kernel.org/stable/c/245165658e1c9f95c0fecfe02b9b1ebd30a1198a