When we receive a new packet from the guest, we check if the
src_cid is correct, but we forgot to check the dst_cid.
The host should accept only packets where dst_cid is
equal to the host CID.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
                virtio_transport_deliver_tap_pkt(pkt);
 
                /* Only accept correctly addressed packets */
-               if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid)
+               if (le64_to_cpu(pkt->hdr.src_cid) == vsock->guest_cid &&
+                   le64_to_cpu(pkt->hdr.dst_cid) ==
+                   vhost_transport_get_local_cid())
                        virtio_transport_recv_pkt(&vhost_transport, pkt);
                else
                        virtio_transport_free_pkt(pkt);