CVE Catalog

CVE-2026-89715

Low risk· EPSS 10%
Published: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.20%

10th percentile - higher than 10% of all known CVEs

Summary

In the Linux kernel, the NFS/localio subsystem has a reference leak when nfs_uuid_add_file() races with nfs_uuid_put() and returns -ENXIO. In that case the error path fails to release the nfsd_file and nfsd_net references, preventing proper teardown of network resources.

Risk Assessment

Each occurrence permanently pins a file reference (including dentry and inode) and an nfsd_net reference, which can block nfsd_net and network namespace teardown. Over time this leads to resource leaks and potential system instability.

Recommendation

Update the Linux kernel to a version containing the fix that releases the file and net references on the error path and returns -ENXIO. A reboot after updating is recommended to release previously leaked resources.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: NFS/localio: fix ref leak on nfs_uuid_add_file failure When nfs_uuid_add_file() races with nfs_uuid_put() tearing down uuid->net, it returns -ENXIO without publishing nfl->nfs_uuid via rcu_assign_pointer(). nfs_open_local_fh() then enters its error branch and only releases the slot's file ref and its paired net ref plus its own entry-time net ref, while the close path is a no-op: nfs_close_local_fh() nfs_uuid = rcu_dereference(nfl->nfs_uuid); if (!nfs_uuid) { rcu_read_unlock(); return; } /* always */ nfsd_open_local_fh() returns localio holding a caller-owned +1 nfsd_file reference (from nfsd_file_get() after nfsd_file_acquire_local()) and an entry-time nfsd_net reference (from its first nfsd_net_try_get()) embedded as nf->nf_net. Both are leaked on the failure path, pinning one nfsd_file (and the underlying struct file, dentry, inode) and one nfsd_net_ref per occurrence, which blocks nfsd_net and netns teardown. Fix by releasing the caller-owned file ref and its net ref through the existing helper, using a stack-local RCU pointer so the helper can xchg it out, then returning -ENXIO so callers do not dereference a localio whose slot has been cleared: struct nfsd_file __rcu *tmp = RCU_INITIALIZER(localio); nfs_to_nfsd_file_put_local(pnf); nfs_to_nfsd_file_put_local(&tmp); localio = ERR_PTR(-ENXIO); The trailing nfs_to_nfsd_net_put(net) continues to release the outer net ref, so all three nfsd_net_try_get() increments are balanced on the error branch.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS