Fix locking in receiver impl; protect session member against concurrent fetch and init.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk/qpid@985838 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 7 insertions, 2 deletions

diff --git a/cpp/src/qpid/client/amqp0_10/ReceiverImpl.cpp b/cpp/src/qpid/client/amqp0_10/ReceiverImpl.cpp
index fb5675c129..6acd0a3ced 100644
--- a/cpp/src/qpid/client/amqp0_10/ReceiverImpl.cpp
+++ b/cpp/src/qpid/client/amqp0_10/ReceiverImpl.cpp
@@ -173,8 +173,13 @@ bool ReceiverImpl::fetchImpl(qpid::messaging::Message& message, qpid::messaging:
     if (getImpl(message, timeout)) {
         return true;
     } else {
-        if (state == CANCELLED) return false; // Might have been closed during get.
-        sync(session).messageFlush(destination);
+        qpid::client::Session s;
+        {
+            sys::Mutex::ScopedLock l(lock);
+            if (state == CANCELLED) return false; // Might have been closed during get.
+            s = sync(session);
+        }
+        s.messageFlush(destination);
         {
             sys::Mutex::ScopedLock l(lock);
             startFlow(l); //reallocate credit