Target/iser: Don't put isert_conn inside disconnected handler

disconnected_handler is invoked on several CM events (such
as DISCONNECTED, DEVICE_REMOVAL, TIMEWAIT_EXIT...). Since
multiple  events can occur while before isert_free_conn is
invoked, we might put all isert_conn references and free
the connection too early.
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/infiniband/ulp/isert/ib_isert.c

@@ -799,7 +799,6 @@ isert_disconnect_work(struct work_struct *work)
 
 wake_up:
 	complete(&isert_conn->conn_wait);
-	isert_put_conn(isert_conn);
 }
 
 static void
@@ -3235,6 +3234,7 @@ static void isert_wait_conn(struct iscsi_conn *conn)
 	wait_for_completion(&isert_conn->conn_wait_comp_err);
 
 	wait_for_completion(&isert_conn->conn_wait);
+	isert_put_conn(isert_conn);
 }
 
 static void isert_free_conn(struct iscsi_conn *conn)