From 5b6c684d26995e720a05ff5d1cd2210e31d041ad Mon Sep 17 00:00:00 2001
From: David Straw <david.straw@hp.com>
Date: Fri, 22 Aug 2014 11:28:24 -0600
Subject: [PATCH] Fix for bug 22307 - Intermittent IndexOutOfRangeException on
 closing connection

---
 .../System.ServiceModel.Dispatcher/ChannelDispatcher.cs    | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/mcs/class/System.ServiceModel/System.ServiceModel.Dispatcher/ChannelDispatcher.cs b/mcs/class/System.ServiceModel/System.ServiceModel.Dispatcher/ChannelDispatcher.cs
index 15731e65a3a..10834fc0ae8 100644
--- a/mcs/class/System.ServiceModel/System.ServiceModel.Dispatcher/ChannelDispatcher.cs
+++ b/mcs/class/System.ServiceModel/System.ServiceModel.Dispatcher/ChannelDispatcher.cs
@@ -452,8 +452,11 @@ namespace System.ServiceModel.Dispatcher
 			public void CloseInput ()
 			{
 				foreach (var ch in channels.ToArray ()) {
-					if (ch.State == CommunicationState.Closed)
-						RemoveChannel (ch);
+					if (ch.State == CommunicationState.Closed) {
+						lock (channels) {
+							RemoveChannel (ch);
+						}
+					}
 					else {
 						try {
 							ch.Close (close_timeout - (DateTime.Now - close_started));
-- 
2.25.1