KVM: s390: pci: Validate AIBV and AISB before pinning guest pages

{
  "id": "40021b28c46f7e35cf0e55b7d9d32d6dc6d39a6264bfa2391c940c14fc0dcbbf",
  "url": "https://osv.dev/vulnerability/CVE-2026-80891",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "KVM: s390: pci: Validate AIBV and AISB before pinning guest pages",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: KVM: s390: pci: Validate AIBV and AISB before pinning guest pages The AIBV holds one bit per MSI-X vector for a given function. The size of the bit vector is derived from the NOI and the AIBVO. If the size of the AIBV exceeds a single page boundary, then reject the request as we cannot safely pin the guest AIBV. Similarly reject the request if the AISB address is not 8-byte aligned as the architecture requires doubleword alignment for the summary bit address. Since the AISBO can address up to 64 bits, the size of the AISB can only be 8 bytes for the function. This also ensures the AISB doesn't exceed a single page boundary.",
    "evidence": "osv:CVE-2026-80891",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.1.183",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.151",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.103",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.44",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.8",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-80891",
      "aliases": [
        "CVE-2026-80891"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "3c5a1b6f0a18520a0edd0600fef6f1a8553b8fdc"
                },
                {
                  "fixed": "3a1c64220ede4ac9ef9a3e76f008ff60a34f4c48"
                },
                {
                  "fixed": "f00ef8efd41440129ccd88f4a1ebebf8d61d297f"
                },
                {
                  "fixed": "15df7700dd99f8a37f5c6ed2dcf1e33009cdba47"
                },
                {
                  "fixed": "b878ba7e28144c9a857bc847d31f3c45413450ac"
                },
                {
                  "fixed": "fbfe683f8b1ae7e40b56bdd6daf5bd671bc3a528"
                },
                {
                  "fixed": "868d32ac72cba21c5c6d8a66a814b7c25a3a5c01"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80891.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.0.0"
                },
                {
                  "fixed": "6.1.183"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.6.151"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.103"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.44"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.1.8"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80891.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:20.679827693Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/15df7700dd99f8a37f5c6ed2dcf1e33009cdba47",
        "https://git.kernel.org/stable/c/3a1c64220ede4ac9ef9a3e76f008ff60a34f4c48",
        "https://git.kernel.org/stable/c/868d32ac72cba21c5c6d8a66a814b7c25a3a5c01",
        "https://git.kernel.org/stable/c/b878ba7e28144c9a857bc847d31f3c45413450ac",
        "https://git.kernel.org/stable/c/f00ef8efd41440129ccd88f4a1ebebf8d61d297f",
        "https://git.kernel.org/stable/c/fbfe683f8b1ae7e40b56bdd6daf5bd671bc3a528",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80891.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-80891",
        "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/2026/80xxx/CVE-2026-80891.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-80891",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 486963,
  "published_at": "2026-09-04T17:11:07.555+00:00"
}