From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-cve-announce@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@kernel.org>
Subject: CVE-2026-43359: btrfs: fix transaction abort on set received ioctl due to item overflow
Date: Fri, 8 May 2026 16:21:28 +0200 [thread overview]
Message-ID: <2026050825-CVE-2026-43359-ec41@gregkh> (raw)
From: Greg Kroah-Hartman <gregkh@kernel.org>
Description
===========
In the Linux kernel, the following vulnerability has been resolved:
btrfs: fix transaction abort on set received ioctl due to item overflow
If the set received ioctl fails due to an item overflow when attempting to
add the BTRFS_UUID_KEY_RECEIVED_SUBVOL we have to abort the transaction
since we did some metadata updates before.
This means that if a user calls this ioctl with the same received UUID
field for a lot of subvolumes, we will hit the overflow, trigger the
transaction abort and turn the filesystem into RO mode. A malicious user
could exploit this, and this ioctl does not even requires that a user
has admin privileges (CAP_SYS_ADMIN), only that he/she owns the subvolume.
Fix this by doing an early check for item overflow before starting a
transaction. This is also race safe because we are holding the subvol_sem
semaphore in exclusive (write) mode.
A test case for fstests will follow soon.
The Linux kernel CVE team has assigned CVE-2026-43359 to this issue.
Affected and fixed versions
===========================
Issue introduced in 3.12 with commit dd5f9615fc5c5e8d3751aab3a17b92768fb1ce70 and fixed in 6.1.167 with commit b9914db13ac15aca3b74544c0bb1a2e0dad1f174
Issue introduced in 3.12 with commit dd5f9615fc5c5e8d3751aab3a17b92768fb1ce70 and fixed in 6.6.130 with commit b19c0465e4daad5aa8f60552ea0578cf31a11b1e
Issue introduced in 3.12 with commit dd5f9615fc5c5e8d3751aab3a17b92768fb1ce70 and fixed in 6.12.78 with commit 2e57b8cac2ba0d38aac76c1ecdfd8b899e3581a5
Issue introduced in 3.12 with commit dd5f9615fc5c5e8d3751aab3a17b92768fb1ce70 and fixed in 6.18.19 with commit d11aefe654a04fc41996d254748d6a38b6b0a7be
Issue introduced in 3.12 with commit dd5f9615fc5c5e8d3751aab3a17b92768fb1ce70 and fixed in 6.19.9 with commit 41fb97353ff58fa4f31904c343fc8e3df2f7517d
Issue introduced in 3.12 with commit dd5f9615fc5c5e8d3751aab3a17b92768fb1ce70 and fixed in 7.0 with commit 87f2c46003fce4d739138aab4af1942b1afdadac
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-2026-43359
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/ioctl.c
fs/btrfs/uuid-tree.c
fs/btrfs/uuid-tree.h
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/b9914db13ac15aca3b74544c0bb1a2e0dad1f174
https://git.kernel.org/stable/c/b19c0465e4daad5aa8f60552ea0578cf31a11b1e
https://git.kernel.org/stable/c/2e57b8cac2ba0d38aac76c1ecdfd8b899e3581a5
https://git.kernel.org/stable/c/d11aefe654a04fc41996d254748d6a38b6b0a7be
https://git.kernel.org/stable/c/41fb97353ff58fa4f31904c343fc8e3df2f7517d
https://git.kernel.org/stable/c/87f2c46003fce4d739138aab4af1942b1afdadac
reply other threads:[~2026-05-08 14:23 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=2026050825-CVE-2026-43359-ec41@gregkh \
--to=gregkh@linuxfoundation.org \
--cc=cve@kernel.org \
--cc=gregkh@kernel.org \
--cc=linux-cve-announce@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox