vhost: fix FD leak with inflight messages

[ upstream commit af74f7db384ed149fe42b21dbd7975f8a54ef227 ]

Even if unlikely, a buggy vhost-user master might attach fds to inflight
messages. Add checks like for other types of vhost-user messages.

Fixes: d87f1a1 ("vhost: support inflight info sharing")
Cc: stable@dpdk.org

lib/librte_vhost/vhost_user.c

@@ -1441,6 +1441,9 @@ vhost_user_get_inflight_fd(struct virtio_net **pdev,
 	int fd, i, j;
 	void *addr;
 
+	if (validate_msg_fds(msg, 0) != 0)
+		return RTE_VHOST_MSG_RESULT_ERR;
+
 	if (msg->size != sizeof(msg->payload.inflight)) {
 		RTE_LOG(ERR, VHOST_CONFIG,
 			"invalid get_inflight_fd message size is %d\n",
@@ -1534,6 +1537,9 @@ vhost_user_set_inflight_fd(struct virtio_net **pdev, VhostUserMsg *msg,
 	void *addr;
 	int fd, i;
 
+	if (validate_msg_fds(msg, 1) != 0)
+		return RTE_VHOST_MSG_RESULT_ERR;
+
 	fd = msg->fds[0];
 	if (msg->size != sizeof(msg->payload.inflight) || fd < 0) {
 		RTE_LOG(ERR, VHOST_CONFIG,