session: handle close before app accept reply

Change-Id: Ic35bbf55851087d70bfacc1eab4dea4285f98c86
Signed-off-by: Florin Coras <fcoras@cisco.com>
diff --git a/src/vnet/session/session_node.c b/src/vnet/session/session_node.c
index eb9026c..58d31cc 100644
--- a/src/vnet/session/session_node.c
+++ b/src/vnet/session/session_node.c
@@ -64,11 +64,9 @@
   else
     {
       s = session_get_from_handle_if_valid (mp->handle);
-      if (!s)
-	{
-	  clib_warning ("session 0x%llx doesn't exist", mp->handle);
-	  return;
-	}
+      /* Closed while waiting for app to reply */
+      if (!s || s->session_state > SESSION_STATE_READY)
+	return;
       app_wrk = app_worker_get (s->app_wrk_index);
       if (app_wrk->app_index != mp->context)
 	{