--- xen-4.5.1/tools/hotplug/Linux/vif-bridge.orig	2015-10-01 17:51:47.613981230 +0200
+++ xen-4.5.1/tools/hotplug/Linux/vif-bridge	2015-10-01 17:51:51.330647734 +0200
@@ -93,8 +93,6 @@
         ;;
 esac
 
-handle_iptable
-
 call_hooks vif post
 
 log debug "Successful vif-bridge $command for $dev, bridge $bridge."
diff -dur -x '*.orig' -x '*.rej' -x '*~' xen-4.2.0.orig/tools/hotplug/Linux/xen-network-common.sh xen-4.2.0/tools/hotplug/Linux/xen-network-common.sh
--- xen-4.2.0.orig/tools/hotplug/Linux/xen-network-common.sh	2012-09-17 12:21:18.000000000 +0200
+++ xen-4.2.0/tools/hotplug/Linux/xen-network-common.sh	2012-10-22 13:05:02.000000000 +0200
@@ -115,6 +115,13 @@
 	brctl addbr ${bridge}
 	brctl stp ${bridge} off
 	brctl setfd ${bridge} 0
+	# Setting these to zero stops guest<->LAN traffic
+	# traversing the bridge from hitting the *tables
+	# rulesets. guest<->host traffic still gets processed
+	# by the host's iptables rules so this isn't a hole
+	sysctl -q -w "net.bridge.bridge-nf-call-arptables=0"
+	sysctl -q -w "net.bridge.bridge-nf-call-ip6tables=0"
+	sysctl -q -w "net.bridge.bridge-nf-call-iptables=0"
     fi
 }