CVE-2025-38393: NFSv4/pNFS: Fix a race to wake on NFS_LAYOUT_DRAIN

Severity: medium (CVSS 4.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-07-25 · updated 2026-07-30
Weakness: CWE-362

Description

In the Linux kernel, the following vulnerability has been resolved: NFSv4/pNFS: Fix a race to wake on NFS_LAYOUT_DRAIN We found a few different systems hung up in writeback waiting on the same page lock, and one task waiting on the NFS_LAYOUT_DRAIN bit in pnfs_update_layout(), however the pnfs_layout_hdr's plh_outstanding count was zero. It seems most likely that this is another race between the waiter and waker similar to commit ed0172af5d6f ("SUNRPC: Fix a race to wake a sync task"). Fix it up by applying the advised barrier.

Affected products

Debian Linux: 11.0
Linux kernel: from 5.10.124 before 5.10.240; from 5.15.49 before 5.15.187; from 5.18.6 before 5.19; from 5.19.1 before 6.1.144; from 6.2 before 6.6.97; from 6.7 before 6.12.37 — fixed in 5.10.240, 5.15.187, 5.19, 6.1.144, 6.12.37, 6.15.6

How to fix

Upgrade to a fixed version: Linux kernel 5.10.240, 5.15.187, 5.19, 6.1.144. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2025-38393 or the next vulnerability affects your stack