CVE-2026-74614: vsock/virtio: read virtqueues under worker locks
In the Linux kernel, the following vulnerability has been resolved:
vsock/virtio: read virtqueues under worker locks
Commit bd50c5dc182b ("vsock/virtio: add support for device suspend/resume") made the run flags transition from false to true when restore installs replacement virtqueues. The RX, TX and event workers read their virtqueue before locking and checking the corresponding flag, so a worker delayed across freeze and restore can observe the replacement queue's running state while retaining a pointer to the deleted queue.
Read each virtqueue under its mutex after checking the run flag, keeping the pointer and state in the same queue generation.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.152.1-1
Event History
Frequently Asked Questions
Under what conditions can this race occur?
The race requires a virtio-vsock worker to be delayed across a device freeze and restore operation. During restore, replacement virtqueues are installed and the run flags transition back to true.
Which paths are involved?
The RX, TX, and event worker paths are involved. Affected workers can retain a pointer to a deleted virtqueue while observing the running state associated with its replacement.
What does the fix change?
The fix reads each virtqueue only under its corresponding worker mutex and after checking the run flag. This keeps the virtqueue pointer and running-state check within the same queue generation.