{"id":"CVE-2026-64460","title":"PCI/IOV: Skip VF Resizable BAR restore on read error","summary":"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 (n…","severity":"high","cvss":7,"cvssVector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:H","cvssSource":"cna","vendor":"Linux","product":"Linux","affected":["Linux >= 5a8f77e24a30bbce2fa57926f3dede84894fd10a < b77524621250407386f44c6eea7e5e4619ada1ce","Linux >= 5a8f77e24a30bbce2fa57926f3dede84894fd10a < 55fd485e66d0ad5c762c23dba1461fe9c741cd96","Linux >= 5a8f77e24a30bbce2fa57926f3dede84894fd10a < f34f1712229d71ce4286440fef12526fd4590b37","Linux 6.17"],"ssvc":{"exploitation":"none","automatable":"no","technicalImpact":"partial","timestamp":"2026-10-16T15:41:12.033503Z"},"published":"2026-07-25","updated":"2026-10-16","sourceUpdated":"2026-10-16T15:42:37.647Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-64460","references":[{"url":"https://git.kernel.org/stable/c/b77524621250407386f44c6eea7e5e4619ada1ce"},{"url":"https://git.kernel.org/stable/c/55fd485e66d0ad5c762c23dba1461fe9c741cd96"},{"url":"https://git.kernel.org/stable/c/f34f1712229d71ce4286440fef12526fd4590b37"}],"tags":["cve.org"],"epss":0.0014,"epssPercentile":0.0303,"ingestedAt":"2026-10-16T17:24:46.822Z","slug":"CVE-2026-64460","body":"## Overview\n\nIn 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().\n\n## Affected\n\n- `Linux >= 5a8f77e24a30bbce2fa57926f3dede84894fd10a < b77524621250407386f44c6eea7e5e4619ada1ce`\n- `Linux >= 5a8f77e24a30bbce2fa57926f3dede84894fd10a < 55fd485e66d0ad5c762c23dba1461fe9c741cd96`\n- `Linux >= 5a8f77e24a30bbce2fa57926f3dede84894fd10a < f34f1712229d71ce4286440fef12526fd4590b37`\n- `Linux 6.17`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":39,"depthScoreParts":{"impact":38.5,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}