{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-64460", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-07-19T15:36:31.789Z", "datePublished": "2026-07-25T08:51:27.568Z", "dateUpdated": "2026-08-17T04:56:05.033Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-17T04:56:05.033Z" }, "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()." } ], "metrics": [ { "cvssV3_1": { "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, "baseSeverity": "HIGH" }, "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." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/pci/iov.c" ], "versions": [ { "version": "5a8f77e24a30bbce2fa57926f3dede84894fd10a", "lessThan": "b77524621250407386f44c6eea7e5e4619ada1ce", "status": "affected", "versionType": "git" }, { "version": "5a8f77e24a30bbce2fa57926f3dede84894fd10a", "lessThan": "55fd485e66d0ad5c762c23dba1461fe9c741cd96", "status": "affected", "versionType": "git" }, { "version": "5a8f77e24a30bbce2fa57926f3dede84894fd10a", "lessThan": "f34f1712229d71ce4286440fef12526fd4590b37", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/pci/iov.c" ], "versions": [ { "version": "6.17", "status": "affected" }, { "version": "0", "lessThan": "6.17", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.39", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.4", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.17", "versionEndExcluding": "6.18.39" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.17", "versionEndExcluding": "7.1.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.17", "versionEndExcluding": "7.2" } ] } ] } ], "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" } ], "title": "PCI/IOV: Skip VF Resizable BAR restore on read error", "x_generator": { "engine": "bippy-1.2.0" } } } }