[Bug] Backport fix for a self-DOS scenario from rust-vmm's vm-virtio

[dianpopa]

Describe the bug

Backport PR rust-vmm/vm-virtio#196 which fixes a self-DOS scenario in the virtio queue logic.
The PR solves an issue where a malitious guest driver could force the virtio device to process some descriptors more than once. This in turn could lead to a self-DOS on the thread processing the queue.

More details on the aformentioned PR.

Environment

[Author TODO: Please supply the following information):]
[ - Firecracker version.]
[ - Host and guest kernel versions.]
[ - Rootfs used.]
[ - Architecture.]
[ - Any other relevant software versions.]

Additional context

[Author TODO: How has this bug affected you?]

[Author TODO: What are you trying to achieve?]

[Author TODO: Do you have any idea of what the solution might be?]

Checks

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