[INET]: Add missed tunnel64_err handler

The tunnel64_protocol uses the tunnel4_protocol's err_handler and
thus calls the tunnel4_protocol's handlers.

This is not very good, as in case of (icmp) error the wrong error
handlers will be called (e.g. ipip ones instead of sit) and this
won't be noticed at all, because the error is not reported.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/tunnel4.c

@@ -118,6 +118,17 @@ static void tunnel4_err(struct sk_buff *skb, u32 info)
 			break;
 }
 
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+static void tunnel64_err(struct sk_buff *skb, u32 info)
+{
+	struct xfrm_tunnel *handler;
+
+	for (handler = tunnel64_handlers; handler; handler = handler->next)
+		if (!handler->err_handler(skb, info))
+			break;
+}
+#endif
+
 static struct net_protocol tunnel4_protocol = {
 	.handler	=	tunnel4_rcv,
 	.err_handler	=	tunnel4_err,
@@ -127,7 +138,7 @@ static struct net_protocol tunnel4_protocol = {
 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
 static struct net_protocol tunnel64_protocol = {
 	.handler	=	tunnel64_rcv,
-	.err_handler	=	tunnel4_err,
+	.err_handler	=	tunnel64_err,
 	.no_policy	=	1,
 };
 #endif