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

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-22 · updated 2026-06-17
Weakness: CWE-416

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.

Affected products

Linux kernel: from 5.9 before 5.10.253; from 5.11 before 5.15.203; from 5.16 before 6.1.168; from 6.2 before 6.6.131; from 6.7 before 6.12.80; from 6.13 before 6.18.21 — fixed in 5.10.253, 5.15.203, 6.1.168, 6.12.80, 6.18.21, 6.19.11

How to fix

Upgrade to a fixed version: Linux kernel 5.10.253, 5.15.203, 6.1.168, 6.12.80. Check the vendor advisory for mitigations.

References

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