vhost/vsock: accept only packets with the right dst_cid

[ Upstream commit 8a3cc29c316c17de590e3ff8b59f3d6cbfd37b0a ]

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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index a775493b7b67dacf1934357e996cbc69d8be22f4..2e37097916b5b1df76a471b83446205083d62c85 100644 (file)
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c
@@ -399,7 +399,9 @@ static void vhost_vsock_handle_tx_kick(struct vhost_work *work)
                len = pkt->len;
 
                /* 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(pkt);
                else
                        virtio_transport_free_pkt(pkt);