linux-cve-announce - CVE-2023-53458: media: cx23885: Fix a null-ptr-deref bug in buffer_prepare() and buffer

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: <2025100105-CVE-2023-53458-8239@gregkh>
Date: Wed,  1 Oct 2025 13:42:28 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2023-53458: media: cx23885: Fix a null-ptr-deref bug in buffer_prepare() and buffer_finish()

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

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

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

media: cx23885: Fix a null-ptr-deref bug in buffer_prepare() and buffer_finish()

When the driver calls cx23885_risc_buffer() to prepare the buffer, the
function call dma_alloc_coherent may fail, resulting in a empty buffer
risc->cpu. Later when we free the buffer or access the buffer, null ptr
deref is triggered.

This bug is similar to the following one:
https://git.linuxtv.org/media_stage.git/commit/?id=2b064d91440b33fba5b452f2d1b31f13ae911d71.

We believe the bug can be also dynamically triggered from user side.
Similarly, we fix this by checking the return value of cx23885_risc_buffer()
and the value of risc->cpu before buffer free.

The Linux kernel CVE team has assigned CVE-2023-53458 to this issue.


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

	Fixed in 5.15.113 with commit f0a06203f2fe63f04311467200c99c4ee1926578
	Fixed in 6.1.30 with commit 6738841f6fcf23e9fc30e2449f32fc84ee19c6f1
	Fixed in 6.3.4 with commit 5b8e5e28e85a546dfccc3895befe0e823fdd7c89
	Fixed in 6.4 with commit 47e8b73bc35d7c54642f78e498697692f6358996

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-2023-53458
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:
	drivers/media/pci/cx23885/cx23885-core.c
	drivers/media/pci/cx23885/cx23885-video.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/f0a06203f2fe63f04311467200c99c4ee1926578
	https://git.kernel.org/stable/c/6738841f6fcf23e9fc30e2449f32fc84ee19c6f1
	https://git.kernel.org/stable/c/5b8e5e28e85a546dfccc3895befe0e823fdd7c89
	https://git.kernel.org/stable/c/47e8b73bc35d7c54642f78e498697692f6358996