From ea07a138bbcf1a5a8953cd55679d2059abcebc49 Mon Sep 17 00:00:00 2001
From: sehraf <sehraf@privatdemail.net>
Date: Tue, 28 Jun 2016 17:37:22 +0200
Subject: [PATCH] fix TcpPacket::readPacket

---
 libretroshare/src/tcponudp/tcppacket.cc | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/libretroshare/src/tcponudp/tcppacket.cc b/libretroshare/src/tcponudp/tcppacket.cc
index 3f308de1a..3351cf168 100644
--- a/libretroshare/src/tcponudp/tcppacket.cc
+++ b/libretroshare/src/tcponudp/tcppacket.cc
@@ -186,19 +186,26 @@ int	TcpPacket::readPacket(void *buf, int size)
 	if (data)
 	{
 		free(data);
+		data = NULL ;
 	}
 	datasize = size - TCP_PSEUDO_HDR_SIZE;
-    
-    	if(datasize == 0)	// this happens!
-        {
-            data = NULL ;
-            return 0 ;
-        }
-        
+
+	// this happens for control packets (e.g. syn/ack/fin)
+	if(datasize == 0)
+	{
+		// data is already NULL
+		// just return packet size
+		return size;
+	}
+
 	data = (uint8 *) rs_malloc(datasize);
 
 	if(data == NULL)
+	{
+		// malloc failed!
+		// return 0 to drop packet (will be retransmitted eventually)
 		return 0 ;
+	}
 
 	/* now the data */
 	memcpy(data, (void *) &(((uint8 *) buf)[20]), datasize);