From 1af2cf37ea36bb4064aeb8dd87a12a3e8a291595 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Chmielowski?= <pchmielowski@process-one.net>
Date: Thu, 26 Jul 2018 18:55:30 +0200
Subject: [PATCH] Wait for more data than just <stream:stream> before sending
 in bosh

This fixes issue #2545
---
 src/ejabberd_bosh.erl | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/src/ejabberd_bosh.erl b/src/ejabberd_bosh.erl
index bbbdaadc7..1a650803e 100644
--- a/src/ejabberd_bosh.erl
+++ b/src/ejabberd_bosh.erl
@@ -365,15 +365,22 @@ wait_for_session(#body{attrs = Attrs} = Req, From,
     {State3, RespEls} = get_response_els(State2),
     State4 = stop_inactivity_timer(State3),
     case RespEls of
-      [] ->
-	  State5 = restart_wait_timer(State4),
-	  Receivers = gb_trees:insert(RID, {From, Resp},
-				      State5#state.receivers),
-	  {next_state, active,
-	   State5#state{receivers = Receivers}};
-      _ ->
-	  reply_next_state(State4, Resp#body{els = RespEls}, RID,
-			   From)
+	[{xmlstreamstart, _, _} = El1] ->
+	    OutBuf = buf_in([El1], State4#state.el_obuf),
+	    State5 = restart_wait_timer(State4),
+	    Receivers = gb_trees:insert(RID, {From, Resp},
+					State5#state.receivers),
+	    {next_state, active,
+	     State5#state{receivers = Receivers, el_obuf = OutBuf}};
+	[] ->
+	    State5 = restart_wait_timer(State4),
+	    Receivers = gb_trees:insert(RID, {From, Resp},
+					State5#state.receivers),
+	    {next_state, active,
+	     State5#state{receivers = Receivers}};
+	_ ->
+	    reply_next_state(State4, Resp#body{els = RespEls}, RID,
+			     From)
     end;
 wait_for_session(_Event, _From, State) ->
     ?ERROR_MSG("unexpected sync event in 'wait_for_session': ~p",