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

{
  "id": "938974d2eb549914c5aad47da99b313833a3741fef4ff255572150e43951dd90",
  "url": "https://osv.dev/vulnerability/CVE-2026-89919",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "KVM: s390: keyop: use mmu_lock to read gmap->asce",
    "summary": "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.",
    "evidence": "osv:CVE-2026-89919",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "7.2.5",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-89919",
      "aliases": [
        "CVE-2026-89919"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0ee4ddc1647b8b3b9e7a94d798a1774a764428c1"
                },
                {
                  "fixed": "ae452b990e0544425f77045351c56e77158858e7"
                },
                {
                  "fixed": "da07a751efa4583385f9f0f47113549fe8871242"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89919.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "7.0.0"
                },
                {
                  "fixed": "7.2.5"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-89919.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:25.112080610Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/ae452b990e0544425f77045351c56e77158858e7",
        "https://git.kernel.org/stable/c/da07a751efa4583385f9f0f47113549fe8871242",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89919.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-89919",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/89xxx/CVE-2026-89919.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-89919",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 491702,
  "published_at": "2026-09-16T10:32:14.013+00:00"
}