CVE-2026-31455 xfs: stop reclaim before pushing AIL during unmount

High 7.8 Published 22 Apr 2026 Updated 11 May 2026

A race condition in the Linux kernel XFS filesystem during unmount can lead to use-after-free, potentially allowing code execution or system crashes.

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-2026-31455?

CVE-2026-31455 is a high-severity use after free vulnerability in Linux kernel, published on 22 Apr 2026. 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:

xfs: stop reclaim before pushing AIL during unmount

The unmount sequence in xfs_unmount_flush_inodes() pushed the AIL while background reclaim and inodegc are still running. This is broken independently of any use-after-free issues - background reclaim and inodegc should not be running while the AIL is being pushed during unmount, as inodegc can dirty and insert inodes into the AIL during the flush, and background reclaim can race to abort and free dirty inodes.

Reorder xfs_unmount_flush_inodes() to stop inodegc and cancel background reclaim before pushing the AIL. Stop inodegc before cancelling m_reclaim_work because the inodegc worker can re-queue m_reclaim_work via xfs_inodegc_set_reclaimable.

Weakness: CWE-416

Which versions are affected by CVE-2026-31455?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-31455?

Apply the vendor's patch.

Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.

Is CVE-2026-31455 being exploited?

There is no known exploitation of CVE-2026-31455 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as AZL-83207, BELL-CVE-2026-31455, DEBIAN-CVE-2026-31455, GHSA-q892-7mjj-mjx9, ROOT-OS-DEBIAN-11-CVE-2026-31455, ROOT-OS-DEBIAN-12-CVE-2026-31455 and 4 more.