CVE-2026-74316: NFSD: Handle layout stid in nfsd4_drop_revoked_stid()

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-15 · updated 2026-10-16

Description

In the Linux kernel, the following vulnerability has been resolved: NFSD: Handle layout stid in nfsd4_drop_revoked_stid() nfsd4_drop_revoked_stid() has no SC_TYPE_LAYOUT case, so when a client sends FREE_STATEID for an admin-revoked layout stid, the default branch releases cl_lock and returns without unhashing or releasing the stid. The stid remains in the IDR and on the per-client list until the client is destroyed. Remove the layout stid from the per-client list and call nfs4_put_stid() to drop the creation reference. When the refcount reaches zero, nfsd4_free_layout_stateid() handles the remaining cleanup: cancelling the fence worker, removing from the per-file list, and freeing the slab object.

Affected products

Linux kernel: 6.9 — fixed in 7.2

How to fix

Upgrade to a fixed version: Linux kernel 7.2. Check the vendor advisory for mitigations.

References

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