Bug 2507147 (CVE-2026-64475)

Summary: CVE-2026-64475 kernel: vfio/pci: Release the VGA arbiter client on register_device() failure
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in the Linux kernel's vfio/pci subsystem. A missing cleanup operation during device registration could lead to a stale registration and a callback using freed memory. This vulnerability could result in system instability or potentially lead to a denial of service.
 Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description OSIDB Bzimport 2026-07-25 10:07:31 UTC 
In the Linux kernel, the following vulnerability has been resolved:

vfio/pci: Release the VGA arbiter client on register_device() failure

The re-order in the Fixes commit below displaced vfio_pci_vga_init() as
the last failure point of what is now vfio_pci_core_register_device()
without introducing an unwind for the VGA arbiter registration.

In current kernels this is mostly benign because vfio_pci_set_decode()
only uses pci_dev state, but the original failure path could leave a
callback with a freed vdev cookie.  The stale registration also becomes
unsafe again once the callback follows drvdata to the vfio device.

Add the required VGA unwind callout.
Comment 1 TEJ RATHI 2026-07-29 15:59:57 UTC 
Upstream advisory:
https://lore.kernel.org/linux-cve-announce/2026072546-CVE-2026-64475-8842@gregkh/T