From 4303b102a6b612ce1a9dd9f442c8b713e3aeb81b Mon Sep 17 00:00:00 2001
From: Nipa Kumar <nipak@juniper.net>
Date: Tue, 10 May 2016 16:01:32 -0700
Subject: [PATCH] Add mutual exclusion on Agent between xmpp::StateMachine and
 io::ReaderTask.

TCP close event on a session is handled by xmpp::StateMachine task and
reads handled by io::ReaderTask, hence both tasks can be accessing the
same session at the same time and xmpp::StateMachine destroying the session
while io::ReaderTask reading it.

Change-Id: I09fbdf9b9ea6c31fb6072e7e2f8d40510f32dc03
Closes-Bug:1560242
---
 src/vnsw/agent/cmn/agent.cc | 6 ++++++
 src/xmpp/xmpp_session.cc    | 4 ----
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/vnsw/agent/cmn/agent.cc b/src/vnsw/agent/cmn/agent.cc
index 46cf909e65d..ff626936412 100644
--- a/src/vnsw/agent/cmn/agent.cc
+++ b/src/vnsw/agent/cmn/agent.cc
@@ -204,6 +204,12 @@ void Agent::SetAgentTaskPolicy() {
     SetTaskPolicyOne("http client", metadata_exclude_list,
                      sizeof(metadata_exclude_list) / sizeof(char *));
 
+    const char *xmpp_state_machine_exclude_list[] = {
+        "io::ReaderTask"
+    };
+    SetTaskPolicyOne("xmpp::StateMachine", xmpp_state_machine_exclude_list,
+                     sizeof(xmpp_state_machine_exclude_list) / sizeof(char *));
+
     const char *agent_init_exclude_list[] = {
         "xmpp::StateMachine",
         "http client",
diff --git a/src/xmpp/xmpp_session.cc b/src/xmpp/xmpp_session.cc
index d2f15da35c1..3ae5514d853 100644
--- a/src/xmpp/xmpp_session.cc
+++ b/src/xmpp/xmpp_session.cc
@@ -283,10 +283,6 @@ void XmppSession::OnRead(Buffer buffer) {
             std::string::const_iterator st = buf_.begin();
             std::string xml = string(st, offset_);
 
-            //
-            // XXX Connection gone ?
-            //
-            if (!connection_) break;
             connection_->ReceiveMsg(this, xml);
 
         } else {