CVE-2025-38314

/// Technical description

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

virtio-pci: Fix result size returned for the admin command completion

The result size returned by virtio_pci_admin_dev_parts_get() is 8 bytes

larger than the actual result data size. This occurs because the

result_sg_size field of the command is filled with the result length

from virtqueue_get_buf(), which includes both the data size and an

additional 8 bytes of status.

This oversized result size causes two issues:

1. The state transferred to the destination includes 8 bytes of extra

data at the end.

2. The allocated buffer in the kernel may be smaller than the returned

size, leading to failures when reading beyond the allocated size.

The commit fixes this by subtracting the status size from the result of

virtqueue_get_buf().

This fix has been tested through live migrations with virtio-net,

virtio-net-transitional, and virtio-blk devices.

/// 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