vfio: prevent infinite loop in vfio_mig_get_next_state() on blocked arc

{
  "id": "d19421b423be7b89415a8c9a0bf864344f62e71f82151d260427d197ed2a8824",
  "url": "https://osv.dev/vulnerability/CVE-2026-64474",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "vfio: prevent infinite loop in vfio_mig_get_next_state() on blocked arc",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: vfio: prevent infinite loop in vfio_mig_get_next_state() on blocked arc vfio_mig_get_next_state() walks vfio_from_fsm_table[] one step at a time, looping to skip optional states the device does not support until *next_fsm is supported. A blocked transition is encoded as VFIO_DEVICE_STATE_ERROR, which the trailing return reports as -EINVAL. The skip loop does not account for the ERROR sentinel. state_flags_table[ERROR] is ~0U and vfio_from_fsm_table[ERROR][*] is ERROR, so once *next_fsm becomes ERROR the loop condition stays true and *next_fsm never changes. The blocked arcs STOP_COPY -> PRE_COPY and STOP_COPY -> PRE_COPY_P2P map to ERROR yet pass the support check on a precopy-capable device, causing the loop to spin forever while holding the driver state mutex. This can result in a soft lockup, and a panic with softlockup_panic set. Terminate the skip loop on the ERROR sentinel so a blocked transition falls through to the existing return and reports -EINVAL.",
    "evidence": "osv:CVE-2026-64474",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.6.145",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.96",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.39",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-64474",
      "aliases": [
        "CVE-2026-64474"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "4db52602a6074e9cc523500b8304600ff63e7b85"
                },
                {
                  "fixed": "8e872c07e40d51a66dee7b280a23a460a2e1e3fa"
                },
                {
                  "fixed": "ed7d5599e6c398da74845767cd1e6a8370a160fc"
                },
                {
                  "fixed": "7f2d6b31089e48db4653df832c9a6afdde9a1c29"
                },
                {
                  "fixed": "a3a8afa2f6e7f0dc266d08f02be3f3054241ba47"
                },
                {
                  "fixed": "a26b499b757cfc8bbff1088bb1b844639e250893"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64474.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.6.145"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.96"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.39"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.1.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64474.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:26.089582137Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/7f2d6b31089e48db4653df832c9a6afdde9a1c29",
        "https://git.kernel.org/stable/c/8e872c07e40d51a66dee7b280a23a460a2e1e3fa",
        "https://git.kernel.org/stable/c/a26b499b757cfc8bbff1088bb1b844639e250893",
        "https://git.kernel.org/stable/c/a3a8afa2f6e7f0dc266d08f02be3f3054241ba47",
        "https://git.kernel.org/stable/c/ed7d5599e6c398da74845767cd1e6a8370a160fc",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64474.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-64474",
        "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/2026/64xxx/CVE-2026-64474.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-64474",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 492661,
  "published_at": "2026-07-25T08:51:37.405+00:00"
}