PCI/IOV: Skip VF Resizable BAR restore on read error

{
  "id": "ff06c1fecf227f54a3f6c9dfcd7eb11b6ac72124e2dc72b3c81413f813cb91b8",
  "url": "https://osv.dev/vulnerability/CVE-2026-64460",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "PCI/IOV: Skip VF Resizable BAR restore on read error",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: PCI/IOV: Skip VF Resizable BAR restore on read error sriov_restore_vf_rebar_state() uses the VF Resizable BAR Control register to decide how many VF BARs to restore (nbars) and which VF BAR each iteration addresses (bar_idx). bar_idx indexes into dev->sriov->barsz[], which has only PCI_SRIOV_NUM_BARS (6) entries. When a device does not respond, config reads typically return PCI_ERROR_RESPONSE (~0). Both fields are 3 bits wide, so nbars and bar_idx both evaluate to 7. The barsz[] access then goes out of bounds. UBSAN reports this as: UBSAN: array-index-out-of-bounds in drivers/pci/iov.c:948:51 index 7 is out of range for type 'resource_size_t [6]' Observed on an NVIDIA RTX PRO 1000 GPU (GB207GLM) that stopped responding during a failed GC6 power state exit. The subsequent pci_restore_state() invoked sriov_restore_vf_rebar_state() while config reads returned 0xffffffff, triggering the splat. Bail out if any VF Resizable BAR Control read returns PCI_ERROR_RESPONSE. No further VF BARs are touched, which is safe because a config read that returns PCI_ERROR_RESPONSE indicates the device is unreachable and restoration is pointless. This mirrors the guard in pci_restore_rebar_state().",
    "evidence": "osv:CVE-2026-64460",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.18.39",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "high",
    "structured": {
      "id": "CVE-2026-64460",
      "aliases": [
        "CVE-2026-64460"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
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              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
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                {
                  "fixed": "b77524621250407386f44c6eea7e5e4619ada1ce"
                },
                {
                  "fixed": "55fd485e66d0ad5c762c23dba1461fe9c741cd96"
                },
                {
                  "fixed": "f34f1712229d71ce4286440fef12526fd4590b37"
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          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64460.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.17.0"
                },
                {
                  "fixed": "6.18.39"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
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                {
                  "fixed": "7.1.4"
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          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64460.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:29.752765024Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/55fd485e66d0ad5c762c23dba1461fe9c741cd96",
        "https://git.kernel.org/stable/c/b77524621250407386f44c6eea7e5e4619ada1ce",
        "https://git.kernel.org/stable/c/f34f1712229d71ce4286440fef12526fd4590b37",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64460.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-64460",
        "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-2026-64460.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-64460",
        "evidence": "/id"
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    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 496799,
  "published_at": "2026-07-25T08:51:27.568+00:00"
}