From d4b4f35a0ecff8fdad416a7f3bab85a2b7a7e375 Mon Sep 17 00:00:00 2001
From: Holger Weiss <holger@zedat.fu-berlin.de>
Date: Tue, 27 Sep 2016 23:22:30 +0200
Subject: [PATCH] ejabberd_http: Handle missing POST data gracefully

Return a "bad request" error instead of crashing if receiving POST/PUT
data fails.
---
 src/ejabberd_http.erl | 29 ++++++++++++++++-------------
 1 file changed, 16 insertions(+), 13 deletions(-)

diff --git a/src/ejabberd_http.erl b/src/ejabberd_http.erl
index 31f80be78..e6e49d9b2 100644
--- a/src/ejabberd_http.erl
+++ b/src/ejabberd_http.erl
@@ -396,18 +396,21 @@ extract_path_query(#state{request_method = Method,
 			  socket = _Socket} = State)
     when (Method =:= 'POST' orelse Method =:= 'PUT') andalso
 	   is_integer(Len) ->
-    {NewState, Data} = recv_data(State, Len),
-    ?DEBUG("client data: ~p~n", [Data]),
-    case catch url_decode_q_split(Path) of
-        {'EXIT', _} -> {NewState, false};
-        {NPath, _Query} ->
-            LPath = normalize_path([NPE
-                                    || NPE <- str:tokens(path_decode(NPath), <<"/">>)]),
-            LQuery = case catch parse_urlencoded(Data) of
-                         {'EXIT', _Reason} -> [];
-                         LQ -> LQ
-                     end,
-            {NewState, {LPath, LQuery, Data}}
+    case recv_data(State, Len) of
+	error -> {State, false};
+	{NewState, Data} ->
+	    ?DEBUG("client data: ~p~n", [Data]),
+	    case catch url_decode_q_split(Path) of
+		{'EXIT', _} -> {NewState, false};
+		{NPath, _Query} ->
+		    LPath = normalize_path([NPE
+					    || NPE <- str:tokens(path_decode(NPath), <<"/">>)]),
+		    LQuery = case catch parse_urlencoded(Data) of
+				 {'EXIT', _Reason} -> [];
+				 LQ -> LQ
+			     end,
+		    {NewState, {LPath, LQuery, Data}}
+	    end
     end;
 extract_path_query(State) ->
     {State, false}.
@@ -525,7 +528,7 @@ recv_data(State, Len, Acc) ->
 		    recv_data(State, Len - byte_size(Data), <<Acc/binary, Data/binary>>);
 		Err ->
 		    ?DEBUG("Cannot receive HTTP data: ~p", [Err]),
-		    <<"">>
+		    error
 	    end;
 	_ ->
 	    Trail = (State#state.trail),