lockd: fix NULL dereference on lockowner allocation failure (CVE-2026-89484) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-89484

lockd: fix NULL dereference on lockowner allocation failure

Answer in brief

CVE-2026-89484 records a Unknown severity vulnerability in lockd: fix NULL dereference on lockowner allocation failure. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 11, 2026Updated Sep 11, 2026Source checked Sep 11, 2026First seen by HOL Sep 11, 2026Material review Sep 11, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <07adfbb3de7529f58ca708a97ead7fa4fdb71056 \|\| >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <d662f7fc04fde305a27f304b3cd19b614d366839 \|\| >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <51af080ca4e553256c59a75a877b9b4fff828311 \|\| >=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <4c7fc129db061c7daab841c4f3c342d894832362	07adfbb3de7529f58ca708a97ead7fa4fdb71056, d662f7fc04fde305a27f304b3cd19b614d366839, 51af080ca4e553256c59a75a877b9b4fff828311, 4c7fc129db061c7daab841c4f3c342d894832362
Linux/Linuxgeneric	2.6.12	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to 07adfbb3de7529f58ca708a97ead7fa4fdb71056 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 11, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 11, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: lockd: fix NULL dereference on lockowner allocation failure nlmclnt_locks_init_private() installs NLM file lock operations even when nlmclnt_find_lockowner() fails to allocate a lockowner. nlmclnt_proc() then returns -ENOMEM, but the VFS still tears down the partially initialized file_lock and calls locks_release_private(). That invokes nlmclnt_locks_release_private(), which dereferences fl->fl_u.nfs_fl.owner and crashes because the owner was never installed. Clear fl_ops before attempting to initialize the NLM private state, and install the NLM lock operations only after a lockowner has been allocated successfully.

Quoted source text, attributed separately from HOL analysis.