linux-cve-announce - CVE-2023-53429: btrfs: don't check PageError in __extent

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 for Android: free password hash cracker in your pocket

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

Message-ID: <2025091857-CVE-2023-53429-dd4c@gregkh>
Date: Thu, 18 Sep 2025 18:04:20 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2023-53429: btrfs: don't check PageError in __extent_writepage

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

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

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

btrfs: don't check PageError in __extent_writepage

__extent_writepage currenly sets PageError whenever any error happens,
and the also checks for PageError to decide if to call error handling.
This leads to very unclear responsibility for cleaning up on errors.
In the VM and generic writeback helpers the basic idea is that once
I/O is fired off all error handling responsibility is delegated to the
end I/O handler.  But if that end I/O handler sets the PageError bit,
and the submitter checks it, the bit could in some cases leak into the
submission context for fast enough I/O.

Fix this by simply not checking PageError and just using the local
ret variable to check for submission errors.  This also fundamentally
solves the long problem documented in a comment in __extent_writepage
by never leaking the error bit into the submission context.

The Linux kernel CVE team has assigned CVE-2023-53429 to this issue.

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

	Fixed in 6.4.7 with commit d40be032ecd8ee1ca033bee43c7755d21fb4d72a
	Fixed in 6.5 with commit 3e92499e3b004baffb479d61e191b41b604ece9a

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-2023-53429
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:
	fs/btrfs/extent_io.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/d40be032ecd8ee1ca033bee43c7755d21fb4d72a
	https://git.kernel.org/stable/c/3e92499e3b004baffb479d61e191b41b604ece9a