Vulnerability-Lookup

GHSA-4G8V-7HMF-PF24

Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-27 06:30

Details

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

7.0 (High)


                  
                    CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:H

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{
  "affected": [],
  "aliases": [
    "CVE-2026-64460"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-25T10:17:31Z",
    "severity": "HIGH"
  },
  "details": "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-\u003esriov-\u003ebarsz[],\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 \u0027resource_size_t [6]\u0027\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().",
  "id": "GHSA-4g8v-7hmf-pf24",
  "modified": "2026-07-27T06:30:39Z",
  "published": "2026-07-25T12:31:36Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64460"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/55fd485e66d0ad5c762c23dba1461fe9c741cd96"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b77524621250407386f44c6eea7e5e4619ada1ce"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/f34f1712229d71ce4286440fef12526fd4590b37"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:H",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-64460 (GCVE-0-2026-64460)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:51 – Updated: 2026-08-17 04:56

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().

Severity

7 (High)


                        
                          CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:H

Assigner

Linux mitre root

References

3 references

URL	Tags
https://git.kernel.org/stable/c/b7752462125040738…
https://git.kernel.org/stable/c/55fd485e66d0ad5c7…
https://git.kernel.org/stable/c/f34f1712229d71ce4…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 5a8f77e24a30bbce2fa57926f3dede84894fd10a , < b77524621250407386f44c6eea7e5e4619ada1ce (git) Affected: 5a8f77e24a30bbce2fa57926f3dede84894fd10a , < 55fd485e66d0ad5c762c23dba1461fe9c741cd96 (git) Affected: 5a8f77e24a30bbce2fa57926f3dede84894fd10a , < f34f1712229d71ce4286440fef12526fd4590b37 (git)
Linux	Linux	Affected: 6.17 Unaffected: 0 , < 6.17 (semver) Unaffected: 6.18.39 , ≤ 6.18.* (semver) Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2 , ≤ * (original_commit_for_fix)

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{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "drivers/pci/iov.c"
          ],
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          "vendor": "Linux",
          "versions": [
            {
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              "status": "affected",
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              "versionType": "git"
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            {
              "lessThan": "55fd485e66d0ad5c762c23dba1461fe9c741cd96",
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              "version": "5a8f77e24a30bbce2fa57926f3dede84894fd10a",
              "versionType": "git"
            },
            {
              "lessThan": "f34f1712229d71ce4286440fef12526fd4590b37",
              "status": "affected",
              "version": "5a8f77e24a30bbce2fa57926f3dede84894fd10a",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
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            "drivers/pci/iov.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.17"
            },
            {
              "lessThan": "6.17",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.39",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.4",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
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                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.17",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "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-\u003esriov-\u003ebarsz[],\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 \u0027resource_size_t [6]\u0027\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()."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The flaw is reachable through local device operations, including DRM render-node runtime resume and delegated VFIO reset or power-management paths, rather than network packet processing.\nAC:H - Triggering the invalid index requires the SR-IOV PF to become PCI-inaccessible so configuration reads return 0xffffffff; the reported failed GC6 exit is a hardware or firmware failure the attacker cannot reliably control.\nPR:L - An ordinary user with DRM render-node or delegated VFIO access can initiate relevant resume or reset activity without a capability check; only the separate PCI sysfs reset path requires init-namespace root.\nUI:N - The attacker can initiate the device-use, resume, or reset sequence without any action by another user.\nS:C - In a VFIO PF-passthrough deployment, tenant-controlled device activity and VM teardown can reach host PCI restoration, so a resulting host oops or panic crosses the guest-to-host security boundary.\nC:L - The fixed index reads one resource_size_t immediately beyond the six-entry barsz array; it is not an arbitrary-read primitive, and only a heavily encoded BAR-size value could become observable if the device resumes.\nI:L - There is no kernel-memory write primitive, but the value derived from the out-of-bounds word is written to VF Resizable BAR control and could cause limited incorrect device configuration if the device becomes responsive.\nA:H - UBSAN trap, panic-on-warn, KASAN, or KFENCE configurations can turn the bounds violation into a host oops or panic, causing complete service loss."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T04:56:05.033Z",
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        "shortName": "Linux"
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          "url": "https://git.kernel.org/stable/c/55fd485e66d0ad5c762c23dba1461fe9c741cd96"
        },
        {
          "url": "https://git.kernel.org/stable/c/f34f1712229d71ce4286440fef12526fd4590b37"
        }
      ],
      "title": "PCI/IOV: Skip VF Resizable BAR restore on read error",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-64460",
    "datePublished": "2026-07-25T08:51:27.568Z",
    "dateReserved": "2026-07-19T15:36:31.789Z",
    "dateUpdated": "2026-08-17T04:56:05.033Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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Confirmed: The vulnerability has been validated from an analyst's perspective.
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Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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GHSA-4G8V-7HMF-PF24

CVE-2026-64460 (GCVE-0-2026-64460)

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