CVE-2026-72472

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

nfs: use nfsi->rwsem to protect traversal of the file lock list

Lingfeng identified a bug and suggested two solutions, but both appear

to have issues.

Generally, we cannot release flc_lock while iterating over the file lock

list to avoid use-after-free (UAF) problems with file locks. However,

functions like nfs_delegation_claim_locks and nfs4_reclaim_locks cannot

adhere to this rule because recover_lock or nfs4_lock_delegation_recall

may take a long time. To resolve this, NFS switches to using nfsi->rwsem

for the same protection, and nfs_reclaim_locks follows this approach.

Although nfs_delegation_claim_locks uses so_delegreturn_mutex instead,

this is inadequate since a single inode can have multiple nfs4_state

instances. Therefore, the fix is to also use nfsi->rwsem in this case.

Furthermore, after commit c69899a17ca4 ("NFSv4: Update of VFS byte range

lock must be atomic with the stateid update"), the functions

nf

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References