KVM: s390: keyop: use mmu_lock to read gmap->asce (CVE-2026-89919) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-89919

KVM: s390: keyop: use mmu_lock to read gmap->asce

Answer in brief

CVE-2026-89919 records a Unknown severity vulnerability in KVM: s390: keyop: use mmu_lock to read gmap->asce. 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 16, 2026Updated Sep 16, 2026Source checked Sep 16, 2026First seen by HOL Sep 16, 2026Material review Sep 16, 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	>=0ee4ddc1647b8b3b9e7a94d798a1774a764428c1 <ae452b990e0544425f77045351c56e77158858e7 \|\| >=0ee4ddc1647b8b3b9e7a94d798a1774a764428c1 <da07a751efa4583385f9f0f47113549fe8871242	ae452b990e0544425f77045351c56e77158858e7, da07a751efa4583385f9f0f47113549fe8871242
Linux/Linuxgeneric	7.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to ae452b990e0544425f77045351c56e77158858e7 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 16, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: KVM: s390: keyop: use mmu_lock to read gmap->asce Every other dat_* consumer in this file (kvm_s390_get_skeys, set_skeys, get_cmma_bits, set_cmma_bits, MEM_CLR_CMMA, kvm_s390_fixup_prefix, kvm_test_age_gfn, kvm_age_gfn) reads kvm->arch.gmap->asce *inside* the mmu_lock read-side. keyop is the only outlier. gmap->asce is mutated under write_lock(mmu_lock) by gmap_set_limit() and keyop might use a stale asce value for walking as KVM_S390_KEYOP and KVM_S390_VM_MEM_LIMIT_SIZE can run concurrently. This can result in memory corruption.

Quoted source text, attributed separately from HOL analysis.