GHSA-4G8V-7HMF-PF24
Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-25 12:31In 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().
{
"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": null
},
"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": "2026-07-25T12:31:36Z",
"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": []
}
Sightings
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Nomenclature
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