CVE-2025-38064

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

virtio: break and reset virtio devices on device_shutdown()

Hongyu reported a hang on kexec in a VM. QEMU reported invalid memory

accesses during the hang.

Invalid read at addr 0x102877002, size 2, region '(null)', reason: rejected

Invalid write at addr 0x102877A44, size 2, region '(null)', reason: rejected

...

It was traced down to virtio-console. Kexec works fine if virtio-console

is not in use.

The issue is that virtio-console continues to write to the MMIO even after

underlying virtio-pci device is reset.

Additionally, Eric noticed that IOMMUs are reset before devices, if

devices are not reset on shutdown they continue to poke at guest memory

and get errors from the IOMMU. Some devices get wedged then.

The problem can be solved by breaking all virtio devices on virtio

bus shutdown, then resetting them.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References