vsock/virtio: flush works in dependency order
In the Linux kernel, the following vulnerability has been resolved: vsock/virtio: flush works in dependency order virtio_vsock_remove() stops the virtqueues and then flushes each work item before freeing the enclosing virtio_vsock. The current order does not account for dependencies between those items: tx_work may queue send_pkt_work, and send_pkt_work may queue rx_work. In particular, send_pkt_work can set restart_rx and release tx_lock. The remove path can then stop the queues and flush rx_work before send_pkt_work queues it. Although the later send_pkt_work flush waits for that producer to finish, nothing waits for the newly queued r