CVE-2023-54311 ext4: fix deadlock when converting an inline directory in nojournal mode
A local attacker can cause a kernel deadlock in ext4 filesystems using inline data in nojournal mode, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-54311?
CVE-2023-54311 is a denial of service vulnerability in Linux, published on 30 Dec 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix deadlock when converting an inline directory in nojournal mode
In no journal mode, ext4_finish_convert_inline_dir() can self-deadlock by calling ext4_handle_dirty_dirblock() when it already has taken the directory lock. There is a similar self-deadlock in ext4_incvert_inline_data_nolock() for data files which we'll fix at the same time.
A simple reproducer demonstrating the problem:
mke2fs -Fq -t ext2 -O inline_data -b 4k /dev/vdc 64 mount -t ext4 -o dirsync /dev/vdc /vdc cd /vdc mkdir file0 cd file0 touch file0 touch file1 attr -s BurnSpaceInEA -V abcde . touch supercalifragilisticexpialidocious
Which versions are affected by CVE-2023-54311?
How do I fix CVE-2023-54311?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-54311 being exploited?
There is no known exploitation of CVE-2023-54311 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2023-54311, DEBIAN-CVE-2023-54311, GHSA-78x5-gg4g-8mmw, UBUNTU-CVE-2023-54311.