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CVE-2026-64460

Full vulnerability record from the local CVENow database.

Description

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().

Severity
HIGH
CVSS score
7.0 (v3.1)
Vulnerability status
Received
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-07-25 10:17:31.193000
Last modified
2026-10-19 21:17:40.227000
View original CVE JSON
{
  "id": "CVE-2026-64460",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-07-25T10:17:31.193",
  "lastModified": "2026-10-19T21:17:40.227",
  "vulnStatus": "Received",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nPCI/IOV: Skip VF Resizable BAR restore on read error\n\nsriov_restore_vf_rebar_state() uses the VF Resizable BAR Control register\nto decide how many VF BARs to restore (nbars) and which VF BAR each\niteration addresses (bar_idx). bar_idx indexes into dev->sriov->barsz[],\nwhich has only PCI_SRIOV_NUM_BARS (6) entries.\n\nWhen a device does not respond, config reads typically return\nPCI_ERROR_RESPONSE (~0).  Both fields are 3 bits wide, so nbars and bar_idx\nboth evaluate to 7. The barsz[] access then goes out of bounds.  UBSAN\nreports this as:\n\n  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]'\n\nObserved on an NVIDIA RTX PRO 1000 GPU (GB207GLM) that stopped responding\nduring a failed GC6 power state exit. The subsequent pci_restore_state()\ninvoked sriov_restore_vf_rebar_state() while config reads returned\n0xffffffff, triggering the splat.\n\nBail out if any VF Resizable BAR Control read returns PCI_ERROR_RESPONSE.\nNo further VF BARs are touched, which is safe because a config read that\nreturns PCI_ERROR_RESPONSE indicates the device is unreachable and\nrestoration is pointless. This mirrors the guard in\npci_restore_rebar_state()."
    }
  ],
  "affected": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "affectedData": [
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "unaffected",
          "programFiles": [
            "drivers/pci/iov.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "5a8f77e24a30bbce2fa57926f3dede84894fd10a",
              "lessThan": "b77524621250407386f44c6eea7e5e4619ada1ce",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5a8f77e24a30bbce2fa57926f3dede84894fd10a",
              "lessThan": "55fd485e66d0ad5c762c23dba1461fe9c741cd96",
              "versionType": "git",
              "status": "affected"
            },
            {
              "version": "5a8f77e24a30bbce2fa57926f3dede84894fd10a",
              "lessThan": "f34f1712229d71ce4286440fef12526fd4590b37",
              "versionType": "git",
              "status": "affected"
            }
          ]
        },
        {
          "vendor": "Linux",
          "product": "Linux",
          "defaultStatus": "affected",
          "programFiles": [
            "drivers/pci/iov.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "versions": [
            {
              "version": "6.17",
              "status": "affected"
            },
            {
              "version": "0",
              "lessThan": "6.17",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "6.18.39",
              "lessThanOrEqual": "6.18.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1.4",
              "lessThanOrEqual": "7.1.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.2",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:H",
          "baseScore": 7.0,
          "baseSeverity": "HIGH",
          "attackVector": "LOCAL",
          "attackComplexity": "HIGH",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.1,
        "impactScore": 5.3
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-16T15:41:12.033503Z",
          "id": "CVE-2026-64460",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://git.kernel.org/stable/c/55fd485e66d0ad5c762c23dba1461fe9c741cd96",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/b77524621250407386f44c6eea7e5e4619ada1ce",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    },
    {
      "url": "https://git.kernel.org/stable/c/f34f1712229d71ce4286440fef12526fd4590b37",
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ]
}