session udp: flag for connected udp

Type: improvement

This can be used as alternative to udpc

Signed-off-by: Florin Coras <fcoras@cisco.com>
Change-Id: Ic3f7efe6728b25d4a8a0b61ddb36de66b4672c4f
diff --git a/src/vnet/session/session.h b/src/vnet/session/session.h
index 0a72f97..d72763a 100644
--- a/src/vnet/session/session.h
+++ b/src/vnet/session/session.h
@@ -591,6 +591,7 @@
 always_inline void
 listen_session_free (session_t * s)
 {
+  ASSERT (!s->rx_fifo);
   session_free (s);
 }