1 files changed, 442 insertions, 608 deletions

diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c
index ee6b7a9f1ec..b75ff6429a0 100644
--- a/net/netfilter/ipvs/ip_vs_xmit.c
+++ b/net/netfilter/ipvs/ip_vs_xmit.c
@@ -17,6 +17,8 @@
  * - not all connections have destination server, for example,
  * connections in backup server when fwmark is used
  * - bypass connections use daddr from packet
+ * - we can use dst without ref while sending in RCU section, we use
+ * ref when returning NF_ACCEPT for NAT-ed packet via loopback
  * LOCAL_OUT rules:
  * - skb->dev is NULL, skb->protocol is not set (both are set in POST_ROUTING)
  * - skb->pkt_type is not set yet
@@ -51,39 +53,54 @@ enum {
 				      */
 	IP_VS_RT_MODE_CONNECT	= 8, /* Always bind route to saddr */
 	IP_VS_RT_MODE_KNOWN_NH	= 16,/* Route via remote addr */
+	IP_VS_RT_MODE_TUNNEL	= 32,/* Tunnel mode */
 };
 
+static inline struct ip_vs_dest_dst *ip_vs_dest_dst_alloc(void)
+{
+	return kmalloc(sizeof(struct ip_vs_dest_dst), GFP_ATOMIC);
+}
+
+static inline void ip_vs_dest_dst_free(struct ip_vs_dest_dst *dest_dst)
+{
+	kfree(dest_dst);
+}
+
 /*
  *      Destination cache to speed up outgoing route lookup
  */
 static inline void
-__ip_vs_dst_set(struct ip_vs_dest *dest, u32 rtos, struct dst_entry *dst,
-		u32 dst_cookie)
+__ip_vs_dst_set(struct ip_vs_dest *dest, struct ip_vs_dest_dst *dest_dst,
+		struct dst_entry *dst, u32 dst_cookie)
 {
-	struct dst_entry *old_dst;
+	struct ip_vs_dest_dst *old;
+
+	old = rcu_dereference_protected(dest->dest_dst,
+					lockdep_is_held(&dest->dst_lock));
 
-	old_dst = dest->dst_cache;
-	dest->dst_cache = dst;
-	dest->dst_rtos = rtos;
-	dest->dst_cookie = dst_cookie;
-	dst_release(old_dst);
+	if (dest_dst) {
+		dest_dst->dst_cache = dst;
+		dest_dst->dst_cookie = dst_cookie;
+	}
+	rcu_assign_pointer(dest->dest_dst, dest_dst);
+
+	if (old)
+		call_rcu(&old->rcu_head, ip_vs_dest_dst_rcu_free);
 }
 
-static inline struct dst_entry *
-__ip_vs_dst_check(struct ip_vs_dest *dest, u32 rtos)
+static inline struct ip_vs_dest_dst *
+__ip_vs_dst_check(struct ip_vs_dest *dest)
 {
-	struct dst_entry *dst = dest->dst_cache;
+	struct ip_vs_dest_dst *dest_dst = rcu_dereference(dest->dest_dst);
+	struct dst_entry *dst;
 
-	if (!dst)
+	if (!dest_dst)
 		return NULL;
-	if ((dst->obsolete || rtos != dest->dst_rtos) &&
-	    dst->ops->check(dst, dest->dst_cookie) == NULL) {
-		dest->dst_cache = NULL;
-		dst_release(dst);
+	dst = dest_dst->dst_cache;
+	if (dst->obsolete &&
+	    dst->ops->check(dst, dest_dst->dst_cookie) == NULL)
 		return NULL;
-	}
-	dst_hold(dst);
-	return dst;
+	return dest_dst;
 }
 
 static inline bool
@@ -104,7 +121,7 @@ __mtu_check_toobig_v6(const struct sk_buff *skb, u32 mtu)
 
 /* Get route to daddr, update *saddr, optionally bind route to saddr */
 static struct rtable *do_output_route4(struct net *net, __be32 daddr,
-				       u32 rtos, int rt_mode, __be32 *saddr)
+				       int rt_mode, __be32 *saddr)
 {
 	struct flowi4 fl4;
 	struct rtable *rt;
@@ -113,7 +130,6 @@ static struct rtable *do_output_route4(struct net *net, __be32 daddr,
 	memset(&fl4, 0, sizeof(fl4));
 	fl4.daddr = daddr;
 	fl4.saddr = (rt_mode & IP_VS_RT_MODE_CONNECT) ? *saddr : 0;
-	fl4.flowi4_tos = rtos;
 	fl4.flowi4_flags = (rt_mode & IP_VS_RT_MODE_KNOWN_NH) ?
 			   FLOWI_FLAG_KNOWN_NH : 0;
 
@@ -124,7 +140,7 @@ retry:
 		if (PTR_ERR(rt) == -EINVAL && *saddr &&
 		    rt_mode & IP_VS_RT_MODE_CONNECT && !loop) {
 			*saddr = 0;
-			flowi4_update_output(&fl4, 0, rtos, daddr, 0);
+			flowi4_update_output(&fl4, 0, 0, daddr, 0);
 			goto retry;
 		}
 		IP_VS_DBG_RL("ip_route_output error, dest: %pI4\n", &daddr);
@@ -132,7 +148,7 @@ retry:
 	} else if (!*saddr && rt_mode & IP_VS_RT_MODE_CONNECT && fl4.saddr) {
 		ip_rt_put(rt);
 		*saddr = fl4.saddr;
-		flowi4_update_output(&fl4, 0, rtos, daddr, fl4.saddr);
+		flowi4_update_output(&fl4, 0, 0, daddr, fl4.saddr);
 		loop++;
 		goto retry;
 	}
@@ -141,113 +157,140 @@ retry:
 }
 
 /* Get route to destination or remote server */
-static struct rtable *
+static int
 __ip_vs_get_out_rt(struct sk_buff *skb, struct ip_vs_dest *dest,
-		   __be32 daddr, u32 rtos, int rt_mode, __be32 *ret_saddr)
+		   __be32 daddr, int rt_mode, __be32 *ret_saddr)
 {
 	struct net *net = dev_net(skb_dst(skb)->dev);
+	struct netns_ipvs *ipvs = net_ipvs(net);
+	struct ip_vs_dest_dst *dest_dst;
 	struct rtable *rt;			/* Route to the other host */
 	struct rtable *ort;			/* Original route */
-	int local;
+	struct iphdr *iph;
+	__be16 df;
+	int mtu;
+	int local, noref = 1;
 
 	if (dest) {
-		spin_lock(&dest->dst_lock);
-		if (!(rt = (struct rtable *)
-		      __ip_vs_dst_check(dest, rtos))) {
-			rt = do_output_route4(net, dest->addr.ip, rtos,
-					      rt_mode, &dest->dst_saddr.ip);
+		dest_dst = __ip_vs_dst_check(dest);
+		if (likely(dest_dst))
+			rt = (struct rtable *) dest_dst->dst_cache;
+		else {
+			dest_dst = ip_vs_dest_dst_alloc();
+			spin_lock_bh(&dest->dst_lock);
+			if (!dest_dst) {
+				__ip_vs_dst_set(dest, NULL, NULL, 0);
+				spin_unlock_bh(&dest->dst_lock);
+				goto err_unreach;
+			}
+			rt = do_output_route4(net, dest->addr.ip, rt_mode,
+					      &dest_dst->dst_saddr.ip);
 			if (!rt) {
-				spin_unlock(&dest->dst_lock);
-				return NULL;
+				__ip_vs_dst_set(dest, NULL, NULL, 0);
+				spin_unlock_bh(&dest->dst_lock);
+				ip_vs_dest_dst_free(dest_dst);
+				goto err_unreach;
 			}
-			__ip_vs_dst_set(dest, rtos, dst_clone(&rt->dst), 0);
-			IP_VS_DBG(10, "new dst %pI4, src %pI4, refcnt=%d, "
-				  "rtos=%X\n",
-				  &dest->addr.ip, &dest->dst_saddr.ip,
-				  atomic_read(&rt->dst.__refcnt), rtos);
+			__ip_vs_dst_set(dest, dest_dst, &rt->dst, 0);
+			spin_unlock_bh(&dest->dst_lock);
+			IP_VS_DBG(10, "new dst %pI4, src %pI4, refcnt=%d\n",
+				  &dest->addr.ip, &dest_dst->dst_saddr.ip,
+				  atomic_read(&rt->dst.__refcnt));
 		}
 		daddr = dest->addr.ip;
 		if (ret_saddr)
-			*ret_saddr = dest->dst_saddr.ip;
-		spin_unlock(&dest->dst_lock);
+			*ret_saddr = dest_dst->dst_saddr.ip;
 	} else {
 		__be32 saddr = htonl(INADDR_ANY);
 
+		noref = 0;
+
 		/* For such unconfigured boxes avoid many route lookups
 		 * for performance reasons because we do not remember saddr
 		 */
 		rt_mode &= ~IP_VS_RT_MODE_CONNECT;
-		rt = do_output_route4(net, daddr, rtos, rt_mode, &saddr);
+		rt = do_output_route4(net, daddr, rt_mode, &saddr);
 		if (!rt)
-			return NULL;
+			goto err_unreach;
 		if (ret_saddr)
 			*ret_saddr = saddr;
 	}
 
-	local = rt->rt_flags & RTCF_LOCAL;
+	local = (rt->rt_flags & RTCF_LOCAL) ? 1 : 0;
 	if (!((local ? IP_VS_RT_MODE_LOCAL : IP_VS_RT_MODE_NON_LOCAL) &
 	      rt_mode)) {
 		IP_VS_DBG_RL("Stopping traffic to %s address, dest: %pI4\n",
 			     (rt->rt_flags & RTCF_LOCAL) ?
 			     "local":"non-local", &daddr);
-		ip_rt_put(rt);
-		return NULL;
-	}
-	if (local && !(rt_mode & IP_VS_RT_MODE_RDR) &&
-	    !((ort = skb_rtable(skb)) && ort->rt_flags & RTCF_LOCAL)) {
-		IP_VS_DBG_RL("Redirect from non-local address %pI4 to local "
-			     "requires NAT method, dest: %pI4\n",
-			     &ip_hdr(skb)->daddr, &daddr);
-		ip_rt_put(rt);
-		return NULL;
+		goto err_put;
 	}
-	if (unlikely(!local && ipv4_is_loopback(ip_hdr(skb)->saddr))) {
-		IP_VS_DBG_RL("Stopping traffic from loopback address %pI4 "
-			     "to non-local address, dest: %pI4\n",
-			     &ip_hdr(skb)->saddr, &daddr);
-		ip_rt_put(rt);
-		return NULL;
+	iph = ip_hdr(skb);
+	if (likely(!local)) {
+		if (unlikely(ipv4_is_loopback(iph->saddr))) {
+			IP_VS_DBG_RL("Stopping traffic from loopback address "
+				     "%pI4 to non-local address, dest: %pI4\n",
+				     &iph->saddr, &daddr);
+			goto err_put;
+		}
+	} else {
+		ort = skb_rtable(skb);
+		if (!(rt_mode & IP_VS_RT_MODE_RDR) &&
+		    !(ort->rt_flags & RTCF_LOCAL)) {
+			IP_VS_DBG_RL("Redirect from non-local address %pI4 to "
+				     "local requires NAT method, dest: %pI4\n",
+				     &iph->daddr, &daddr);
+			goto err_put;
+		}
+		/* skb to local stack, preserve old route */
+		if (!noref)
+			ip_rt_put(rt);
+		return local;
 	}
 
-	return rt;
-}
-
-/* Reroute packet to local IPv4 stack after DNAT */
-static int
-__ip_vs_reroute_locally(struct sk_buff *skb)
-{
-	struct rtable *rt = skb_rtable(skb);
-	struct net_device *dev = rt->dst.dev;
-	struct net *net = dev_net(dev);
-	struct iphdr *iph = ip_hdr(skb);
-
-	if (rt_is_input_route(rt)) {
-		unsigned long orefdst = skb->_skb_refdst;
-
-		if (ip_route_input(skb, iph->daddr, iph->saddr,
-				   iph->tos, skb->dev))
-			return 0;
-		refdst_drop(orefdst);
+	if (likely(!(rt_mode & IP_VS_RT_MODE_TUNNEL))) {
+		mtu = dst_mtu(&rt->dst);
+		df = iph->frag_off & htons(IP_DF);
 	} else {
-		struct flowi4 fl4 = {
-			.daddr = iph->daddr,
-			.saddr = iph->saddr,
-			.flowi4_tos = RT_TOS(iph->tos),
-			.flowi4_mark = skb->mark,
-		};
-
-		rt = ip_route_output_key(net, &fl4);
-		if (IS_ERR(rt))
-			return 0;
-		if (!(rt->rt_flags & RTCF_LOCAL)) {
-			ip_rt_put(rt);
-			return 0;
+		struct sock *sk = skb->sk;
+
+		mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr);
+		if (mtu < 68) {
+			IP_VS_DBG_RL("%s(): mtu less than 68\n", __func__);
+			goto err_put;
 		}
-		/* Drop old route. */
-		skb_dst_drop(skb);
-		skb_dst_set(skb, &rt->dst);
+		ort = skb_rtable(skb);
+		if (!skb->dev && sk && sk->sk_state != TCP_TIME_WAIT)
+			ort->dst.ops->update_pmtu(&ort->dst, sk, NULL, mtu);
+		/* MTU check allowed? */
+		df = sysctl_pmtu_disc(ipvs) ? iph->frag_off & htons(IP_DF) : 0;
 	}
-	return 1;
+
+	/* MTU checking */
+	if (unlikely(df && skb->len > mtu && !skb_is_gso(skb))) {
+		icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
+		IP_VS_DBG(1, "frag needed for %pI4\n", &iph->saddr);
+		goto err_put;
+	}
+
+	skb_dst_drop(skb);
+	if (noref) {
+		if (!local)
+			skb_dst_set_noref_force(skb, &rt->dst);
+		else
+			skb_dst_set(skb, dst_clone(&rt->dst));
+	} else
+		skb_dst_set(skb, &rt->dst);
+
+	return local;
+
+err_put:
+	if (!noref)
+		ip_rt_put(rt);
+	return -1;
+
+err_unreach:
+	dst_link_failure(skb);
+	return -1;
 }
 
 #ifdef CONFIG_IP_VS_IPV6
@@ -294,44 +337,57 @@ out_err:
 /*
  * Get route to destination or remote server
  */
-static struct rt6_info *
+static int
 __ip_vs_get_out_rt_v6(struct sk_buff *skb, struct ip_vs_dest *dest,
 		      struct in6_addr *daddr, struct in6_addr *ret_saddr,
-		      int do_xfrm, int rt_mode)
+		      struct ip_vs_iphdr *ipvsh, int do_xfrm, int rt_mode)
 {
 	struct net *net = dev_net(skb_dst(skb)->dev);
+	struct ip_vs_dest_dst *dest_dst;
 	struct rt6_info *rt;			/* Route to the other host */
 	struct rt6_info *ort;			/* Original route */
 	struct dst_entry *dst;
-	int local;
+	int mtu;
+	int local, noref = 1;
 
 	if (dest) {
-		spin_lock(&dest->dst_lock);
-		rt = (struct rt6_info *)__ip_vs_dst_check(dest, 0);
-		if (!rt) {
+		dest_dst = __ip_vs_dst_check(dest);
+		if (likely(dest_dst))
+			rt = (struct rt6_info *) dest_dst->dst_cache;
+		else {
 			u32 cookie;
 
+			dest_dst = ip_vs_dest_dst_alloc();
+			spin_lock_bh(&dest->dst_lock);
+			if (!dest_dst) {
+				__ip_vs_dst_set(dest, NULL, NULL, 0);
+				spin_unlock_bh(&dest->dst_lock);
+				goto err_unreach;
+			}
 			dst = __ip_vs_route_output_v6(net, &dest->addr.in6,
-						      &dest->dst_saddr.in6,
+						      &dest_dst->dst_saddr.in6,
 						      do_xfrm);
 			if (!dst) {
-				spin_unlock(&dest->dst_lock);
-				return NULL;
+				__ip_vs_dst_set(dest, NULL, NULL, 0);
+				spin_unlock_bh(&dest->dst_lock);
+				ip_vs_dest_dst_free(dest_dst);
+				goto err_unreach;
 			}
 			rt = (struct rt6_info *) dst;
 			cookie = rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0;
-			__ip_vs_dst_set(dest, 0, dst_clone(&rt->dst), cookie);
+			__ip_vs_dst_set(dest, dest_dst, &rt->dst, cookie);
+			spin_unlock_bh(&dest->dst_lock);
 			IP_VS_DBG(10, "new dst %pI6, src %pI6, refcnt=%d\n",
-				  &dest->addr.in6, &dest->dst_saddr.in6,
+				  &dest->addr.in6, &dest_dst->dst_saddr.in6,
 				  atomic_read(&rt->dst.__refcnt));
 		}
 		if (ret_saddr)
-			*ret_saddr = dest->dst_saddr.in6;
-		spin_unlock(&dest->dst_lock);
+			*ret_saddr = dest_dst->dst_saddr.in6;
 	} else {
+		noref = 0;
 		dst = __ip_vs_route_output_v6(net, daddr, ret_saddr, do_xfrm);
 		if (!dst)
-			return NULL;
+			goto err_unreach;
 		rt = (struct rt6_info *) dst;
 	}
 
@@ -340,86 +396,137 @@ __ip_vs_get_out_rt_v6(struct sk_buff *skb, struct ip_vs_dest *dest,
 	      rt_mode)) {
 		IP_VS_DBG_RL("Stopping traffic to %s address, dest: %pI6c\n",
 			     local ? "local":"non-local", daddr);
-		dst_release(&rt->dst);
-		return NULL;
+		goto err_put;
 	}
-	if (local && !(rt_mode & IP_VS_RT_MODE_RDR) &&
-	    !((ort = (struct rt6_info *) skb_dst(skb)) &&
-	      __ip_vs_is_local_route6(ort))) {
-		IP_VS_DBG_RL("Redirect from non-local address %pI6c to local "
-			     "requires NAT method, dest: %pI6c\n",
-			     &ipv6_hdr(skb)->daddr, daddr);
-		dst_release(&rt->dst);
-		return NULL;
+	if (likely(!local)) {
+		if (unlikely((!skb->dev || skb->dev->flags & IFF_LOOPBACK) &&
+			     ipv6_addr_type(&ipv6_hdr(skb)->saddr) &
+					    IPV6_ADDR_LOOPBACK)) {
+			IP_VS_DBG_RL("Stopping traffic from loopback address "
+				     "%pI6c to non-local address, "
+				     "dest: %pI6c\n",
+				     &ipv6_hdr(skb)->saddr, daddr);
+			goto err_put;
+		}
+	} else {
+		ort = (struct rt6_info *) skb_dst(skb);
+		if (!(rt_mode & IP_VS_RT_MODE_RDR) &&
+		    !__ip_vs_is_local_route6(ort)) {
+			IP_VS_DBG_RL("Redirect from non-local address %pI6c "
+				     "to local requires NAT method, "
+				     "dest: %pI6c\n",
+				     &ipv6_hdr(skb)->daddr, daddr);
+			goto err_put;
+		}
+		/* skb to local stack, preserve old route */
+		if (!noref)
+			dst_release(&rt->dst);
+		return local;
 	}
-	if (unlikely(!local && (!skb->dev || skb->dev->flags & IFF_LOOPBACK) &&
-		     ipv6_addr_type(&ipv6_hdr(skb)->saddr) &
-				    IPV6_ADDR_LOOPBACK)) {
-		IP_VS_DBG_RL("Stopping traffic from loopback address %pI6c "
-			     "to non-local address, dest: %pI6c\n",
-			     &ipv6_hdr(skb)->saddr, daddr);
-		dst_release(&rt->dst);
-		return NULL;
+
+	/* MTU checking */
+	if (likely(!(rt_mode & IP_VS_RT_MODE_TUNNEL)))
+		mtu = dst_mtu(&rt->dst);
+	else {
+		struct sock *sk = skb->sk;
+
+		mtu = dst_mtu(&rt->dst) - sizeof(struct ipv6hdr);
+		if (mtu < IPV6_MIN_MTU) {
+			IP_VS_DBG_RL("%s(): mtu less than %d\n", __func__,
+				     IPV6_MIN_MTU);
+			goto err_put;
+		}
+		ort = (struct rt6_info *) skb_dst(skb);
+		if (!skb->dev && sk && sk->sk_state != TCP_TIME_WAIT)
+			ort->dst.ops->update_pmtu(&ort->dst, sk, NULL, mtu);
 	}
 
-	return rt;
+	if (unlikely(__mtu_check_toobig_v6(skb, mtu))) {
+		if (!skb->dev)
+			skb->dev = net->loopback_dev;
+		/* only send ICMP too big on first fragment */
+		if (!ipvsh->fragoffs)
+			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
+		IP_VS_DBG(1, "frag needed for %pI6c\n", &ipv6_hdr(skb)->saddr);
+		goto err_put;
+	}
+
+	skb_dst_drop(skb);
+	if (noref) {
+		if (!local)
+			skb_dst_set_noref_force(skb, &rt->dst);
+		else
+			skb_dst_set(skb, dst_clone(&rt->dst));
+	} else
+		skb_dst_set(skb, &rt->dst);
+
+	return local;
+
+err_put:
+	if (!noref)
+		dst_release(&rt->dst);
+	return -1;
+
+err_unreach:
+	dst_link_failure(skb);
+	return -1;
 }
 #endif
 
 
-/*
- *	Release dest->dst_cache before a dest is removed
- */
-void
-ip_vs_dst_reset(struct ip_vs_dest *dest)
+/* return NF_ACCEPT to allow forwarding or other NF_xxx on error */
+static inline int ip_vs_tunnel_xmit_prepare(struct sk_buff *skb,
+					    struct ip_vs_conn *cp)
 {
-	struct dst_entry *old_dst;
+	int ret = NF_ACCEPT;
+
+	skb->ipvs_property = 1;
+	if (unlikely(cp->flags & IP_VS_CONN_F_NFCT))
+		ret = ip_vs_confirm_conntrack(skb);
+	if (ret == NF_ACCEPT) {
+		nf_reset(skb);
+		skb_forward_csum(skb);
+	}
+	return ret;
+}
+
+/* return NF_STOLEN (sent) or NF_ACCEPT if local=1 (not sent) */
+static inline int ip_vs_nat_send_or_cont(int pf, struct sk_buff *skb,
+					 struct ip_vs_conn *cp, int local)
+{
+	int ret = NF_STOLEN;
 
-	old_dst = dest->dst_cache;
-	dest->dst_cache = NULL;
-	dst_release(old_dst);
-	dest->dst_saddr.ip = 0;
+	skb->ipvs_property = 1;
+	if (likely(!(cp->flags & IP_VS_CONN_F_NFCT)))
+		ip_vs_notrack(skb);
+	else
+		ip_vs_update_conntrack(skb, cp, 1);
+	if (!local) {
+		skb_forward_csum(skb);
+		NF_HOOK(pf, NF_INET_LOCAL_OUT, skb, NULL, skb_dst(skb)->dev,
+			dst_output);
+	} else
+		ret = NF_ACCEPT;
+	return ret;
 }
 
-#define IP_VS_XMIT_TUNNEL(skb, cp)				\
-({								\
-	int __ret = NF_ACCEPT;					\
-								\
-	(skb)->ipvs_property = 1;				\
-	if (unlikely((cp)->flags & IP_VS_CONN_F_NFCT))		\
-		__ret = ip_vs_confirm_conntrack(skb);		\
-	if (__ret == NF_ACCEPT) {				\
-		nf_reset(skb);					\
-		skb_forward_csum(skb);				\
-	}							\
-	__ret;							\
-})
-
-#define IP_VS_XMIT_NAT(pf, skb, cp, local)		\
-do {							\
-	(skb)->ipvs_property = 1;			\
-	if (likely(!((cp)->flags & IP_VS_CONN_F_NFCT)))	\
-		ip_vs_notrack(skb);			\
-	else						\
-		ip_vs_update_conntrack(skb, cp, 1);	\
-	if (local)					\
-		return NF_ACCEPT;			\
-	skb_forward_csum(skb);				\
-	NF_HOOK(pf, NF_INET_LOCAL_OUT, (skb), NULL,	\
-		skb_dst(skb)->dev, dst_output);		\
-} while (0)
-
-#define IP_VS_XMIT(pf, skb, cp, local)			\
-do {							\
-	(skb)->ipvs_property = 1;			\
-	if (likely(!((cp)->flags & IP_VS_CONN_F_NFCT)))	\
-		ip_vs_notrack(skb);			\
-	if (local)					\
-		return NF_ACCEPT;			\
-	skb_forward_csum(skb);				\
-	NF_HOOK(pf, NF_INET_LOCAL_OUT, (skb), NULL,	\
-		skb_dst(skb)->dev, dst_output);		\
-} while (0)
+/* return NF_STOLEN (sent) or NF_ACCEPT if local=1 (not sent) */
+static inline int ip_vs_send_or_cont(int pf, struct sk_buff *skb,
+				     struct ip_vs_conn *cp, int local)
+{
+	int ret = NF_STOLEN;
+
+	skb->ipvs_property = 1;
+	if (likely(!(cp->flags & IP_VS_CONN_F_NFCT)))
+		ip_vs_notrack(skb);
+	if (!local) {
+		skb_forward_csum(skb);
+		NF_HOOK(pf, NF_INET_LOCAL_OUT, skb, NULL, skb_dst(skb)->dev,
+			dst_output);
+	} else
+		ret = NF_ACCEPT;
+	return ret;
+}
 
 
 /*
@@ -430,7 +537,7 @@ ip_vs_null_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 		struct ip_vs_protocol *pp, struct ip_vs_iphdr *ipvsh)
 {
 	/* we do not touch skb and do not need pskb ptr */
-	IP_VS_XMIT(NFPROTO_IPV4, skb, cp, 1);
+	return ip_vs_send_or_cont(NFPROTO_IPV4, skb, cp, 1);
 }
 
 
@@ -443,52 +550,29 @@ int
 ip_vs_bypass_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 		  struct ip_vs_protocol *pp, struct ip_vs_iphdr *ipvsh)
 {
-	struct rtable *rt;			/* Route to the other host */
 	struct iphdr  *iph = ip_hdr(skb);
-	int    mtu;
 
 	EnterFunction(10);
 
-	if (!(rt = __ip_vs_get_out_rt(skb, NULL, iph->daddr, RT_TOS(iph->tos),
-				      IP_VS_RT_MODE_NON_LOCAL, NULL)))
-		goto tx_error_icmp;
-
-	/* MTU checking */
-	mtu = dst_mtu(&rt->dst);
-	if ((skb->len > mtu) && (iph->frag_off & htons(IP_DF)) &&
-	    !skb_is_gso(skb)) {
-		ip_rt_put(rt);
-		icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu));
-		IP_VS_DBG_RL("%s(): frag needed\n", __func__);
+	rcu_read_lock();
+	if (__ip_vs_get_out_rt(skb, NULL, iph->daddr, IP_VS_RT_MODE_NON_LOCAL,
+			       NULL) < 0)
 		goto tx_error;
-	}
 
-	/*
-	 * Call ip_send_check because we are not sure it is called
-	 * after ip_defrag. Is copy-on-write needed?
-	 */
-	if (unlikely((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)) {
-		ip_rt_put(rt);
-		return NF_STOLEN;
-	}
-	ip_send_check(ip_hdr(skb));
-
-	/* drop old route */
-	skb_dst_drop(skb);
-	skb_dst_set(skb, &rt->dst);
+	ip_send_check(iph);
 
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	IP_VS_XMIT(NFPROTO_IPV4, skb, cp, 0);
+	ip_vs_send_or_cont(NFPROTO_IPV4, skb, cp, 0);
+	rcu_read_unlock();
 
 	LeaveFunction(10);
 	return NF_STOLEN;
 
- tx_error_icmp:
-	dst_link_failure(skb);
  tx_error:
 	kfree_skb(skb);
+	rcu_read_unlock();
 	LeaveFunction(10);
 	return NF_STOLEN;
 }
@@ -496,60 +580,27 @@ ip_vs_bypass_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 #ifdef CONFIG_IP_VS_IPV6
 int
 ip_vs_bypass_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
-		     struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph)
+		     struct ip_vs_protocol *pp, struct ip_vs_iphdr *ipvsh)
 {
-	struct rt6_info *rt;			/* Route to the other host */
-	int    mtu;
-
 	EnterFunction(10);
 
-	rt = __ip_vs_get_out_rt_v6(skb, NULL, &iph->daddr.in6, NULL, 0,
-				   IP_VS_RT_MODE_NON_LOCAL);
-	if (!rt)
-		goto tx_error_icmp;
-
-	/* MTU checking */
-	mtu = dst_mtu(&rt->dst);
-	if (__mtu_check_toobig_v6(skb, mtu)) {
-		if (!skb->dev) {
-			struct net *net = dev_net(skb_dst(skb)->dev);
-
-			skb->dev = net->loopback_dev;
-		}
-		/* only send ICMP too big on first fragment */
-		if (!iph->fragoffs)
-			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
-		dst_release(&rt->dst);
-		IP_VS_DBG_RL("%s(): frag needed\n", __func__);
+	rcu_read_lock();
+	if (__ip_vs_get_out_rt_v6(skb, NULL, &ipvsh->daddr.in6, NULL,
+				  ipvsh, 0, IP_VS_RT_MODE_NON_LOCAL) < 0)
 		goto tx_error;
-	}
-
-	/*
-	 * Call ip_send_check because we are not sure it is called
-	 * after ip_defrag. Is copy-on-write needed?
-	 */
-	skb = skb_share_check(skb, GFP_ATOMIC);
-	if (unlikely(skb == NULL)) {
-		dst_release(&rt->dst);
-		return NF_STOLEN;
-	}
-
-	/* drop old route */
-	skb_dst_drop(skb);
-	skb_dst_set(skb, &rt->dst);
 
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	IP_VS_XMIT(NFPROTO_IPV6, skb, cp, 0);
+	ip_vs_send_or_cont(NFPROTO_IPV6, skb, cp, 0);
+	rcu_read_unlock();
 
 	LeaveFunction(10);
 	return NF_STOLEN;
 
- tx_error_icmp:
-	dst_link_failure(skb);
  tx_error:
 	kfree_skb(skb);
+	rcu_read_unlock();
 	LeaveFunction(10);
 	return NF_STOLEN;
 }
@@ -564,29 +615,30 @@ ip_vs_nat_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 	       struct ip_vs_protocol *pp, struct ip_vs_iphdr *ipvsh)
 {
 	struct rtable *rt;		/* Route to the other host */
-	int mtu;
-	struct iphdr *iph = ip_hdr(skb);
-	int local;
+	int local, rc, was_input;
 
 	EnterFunction(10);
 
+	rcu_read_lock();
 	/* check if it is a connection of no-client-port */
 	if (unlikely(cp->flags & IP_VS_CONN_F_NO_CPORT)) {
 		__be16 _pt, *p;
-		p = skb_header_pointer(skb, iph->ihl*4, sizeof(_pt), &_pt);
+
+		p = skb_header_pointer(skb, ipvsh->len, sizeof(_pt), &_pt);
 		if (p == NULL)
 			goto tx_error;
 		ip_vs_conn_fill_cport(cp, *p);
 		IP_VS_DBG(10, "filled cport=%d\n", ntohs(*p));
 	}
 
-	if (!(rt = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip,
-				      RT_TOS(iph->tos),
-				      IP_VS_RT_MODE_LOCAL |
-					IP_VS_RT_MODE_NON_LOCAL |
-					IP_VS_RT_MODE_RDR, NULL)))
-		goto tx_error_icmp;
-	local = rt->rt_flags & RTCF_LOCAL;
+	was_input = rt_is_input_route(skb_rtable(skb));
+	local = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip,
+				   IP_VS_RT_MODE_LOCAL |
+				   IP_VS_RT_MODE_NON_LOCAL |
+				   IP_VS_RT_MODE_RDR, NULL);
+	if (local < 0)
+		goto tx_error;
+	rt = skb_rtable(skb);
 	/*
 	 * Avoid duplicate tuple in reply direction for NAT traffic
 	 * to local address when connection is sync-ed
@@ -600,57 +652,31 @@ ip_vs_nat_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 			IP_VS_DBG_RL_PKT(10, AF_INET, pp, skb, 0,
 					 "ip_vs_nat_xmit(): "
 					 "stopping DNAT to local address");
-			goto tx_error_put;
+			goto tx_error;
 		}
 	}
 #endif
 
 	/* From world but DNAT to loopback address? */
-	if (local && ipv4_is_loopback(cp->daddr.ip) &&
-	    rt_is_input_route(skb_rtable(skb))) {
+	if (local && ipv4_is_loopback(cp->daddr.ip) && was_input) {
 		IP_VS_DBG_RL_PKT(1, AF_INET, pp, skb, 0, "ip_vs_nat_xmit(): "
 				 "stopping DNAT to loopback address");
-		goto tx_error_put;
-	}
-
-	/* MTU checking */
-	mtu = dst_mtu(&rt->dst);
-	if ((skb->len > mtu) && (iph->frag_off & htons(IP_DF)) &&
-	    !skb_is_gso(skb)) {
-		icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu));
-		IP_VS_DBG_RL_PKT(0, AF_INET, pp, skb, 0,
-				 "ip_vs_nat_xmit(): frag needed for");
-		goto tx_error_put;
+		goto tx_error;
 	}
 
 	/* copy-on-write the packet before mangling it */
 	if (!skb_make_writable(skb, sizeof(struct iphdr)))
-		goto tx_error_put;
+		goto tx_error;
 
 	if (skb_cow(skb, rt->dst.dev->hard_header_len))
-		goto tx_error_put;
+		goto tx_error;
 
 	/* mangle the packet */
 	if (pp->dnat_handler && !pp->dnat_handler(skb, pp, cp, ipvsh))
-		goto tx_error_put;
+		goto tx_error;
 	ip_hdr(skb)->daddr = cp->daddr.ip;
 	ip_send_check(ip_hdr(skb));
 
-	if (!local) {
-		/* drop old route */
-		skb_dst_drop(skb);
-		skb_dst_set(skb, &rt->dst);
-	} else {
-		ip_rt_put(rt);
-		/*
-		 * Some IPv4 replies get local address from routes,
-		 * not from iph, so while we DNAT after routing
-		 * we need this second input/output route.
-		 */
-		if (!__ip_vs_reroute_locally(skb))
-			goto tx_error;
-	}
-
 	IP_VS_DBG_PKT(10, AF_INET, pp, skb, 0, "After DNAT");
 
 	/* FIXME: when application helper enlarges the packet and the length
@@ -660,49 +686,48 @@ ip_vs_nat_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	IP_VS_XMIT_NAT(NFPROTO_IPV4, skb, cp, local);
+	rc = ip_vs_nat_send_or_cont(NFPROTO_IPV4, skb, cp, local);
+	rcu_read_unlock();
 
 	LeaveFunction(10);
-	return NF_STOLEN;
+	return rc;
 
-  tx_error_icmp:
-	dst_link_failure(skb);
   tx_error:
 	kfree_skb(skb);
+	rcu_read_unlock();
 	LeaveFunction(10);
 	return NF_STOLEN;
-  tx_error_put:
-	ip_rt_put(rt);
-	goto tx_error;
 }
 
 #ifdef CONFIG_IP_VS_IPV6
 int
 ip_vs_nat_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
-		  struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph)
+		  struct ip_vs_protocol *pp, struct ip_vs_iphdr *ipvsh)
 {
 	struct rt6_info *rt;		/* Route to the other host */
-	int mtu;
-	int local;
+	int local, rc;
 
 	EnterFunction(10);
 
+	rcu_read_lock();
 	/* check if it is a connection of no-client-port */
-	if (unlikely(cp->flags & IP_VS_CONN_F_NO_CPORT && !iph->fragoffs)) {
+	if (unlikely(cp->flags & IP_VS_CONN_F_NO_CPORT && !ipvsh->fragoffs)) {
 		__be16 _pt, *p;
-		p = skb_header_pointer(skb, iph->len, sizeof(_pt), &_pt);
+		p = skb_header_pointer(skb, ipvsh->len, sizeof(_pt), &_pt);
 		if (p == NULL)
 			goto tx_error;
 		ip_vs_conn_fill_cport(cp, *p);
 		IP_VS_DBG(10, "filled cport=%d\n", ntohs(*p));
 	}
 
-	if (!(rt = __ip_vs_get_out_rt_v6(skb, cp->dest, &cp->daddr.in6, NULL,
-					 0, (IP_VS_RT_MODE_LOCAL |
-					     IP_VS_RT_MODE_NON_LOCAL |
-					     IP_VS_RT_MODE_RDR))))
-		goto tx_error_icmp;
-	local = __ip_vs_is_local_route6(rt);
+	local = __ip_vs_get_out_rt_v6(skb, cp->dest, &cp->daddr.in6, NULL,
+				      ipvsh, 0,
+				      IP_VS_RT_MODE_LOCAL |
+				      IP_VS_RT_MODE_NON_LOCAL |
+				      IP_VS_RT_MODE_RDR);
+	if (local < 0)
+		goto tx_error;
+	rt = (struct rt6_info *) skb_dst(skb);
 	/*
 	 * Avoid duplicate tuple in reply direction for NAT traffic
 	 * to local address when connection is sync-ed
@@ -716,7 +741,7 @@ ip_vs_nat_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 			IP_VS_DBG_RL_PKT(10, AF_INET6, pp, skb, 0,
 					 "ip_vs_nat_xmit_v6(): "
 					 "stopping DNAT to local address");
-			goto tx_error_put;
+			goto tx_error;
 		}
 	}
 #endif
@@ -727,46 +752,21 @@ ip_vs_nat_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 		IP_VS_DBG_RL_PKT(1, AF_INET6, pp, skb, 0,
 				 "ip_vs_nat_xmit_v6(): "
 				 "stopping DNAT to loopback address");
-		goto tx_error_put;
-	}
-
-	/* MTU checking */
-	mtu = dst_mtu(&rt->dst);
-	if (__mtu_check_toobig_v6(skb, mtu)) {
-		if (!skb->dev) {
-			struct net *net = dev_net(skb_dst(skb)->dev);
-
-			skb->dev = net->loopback_dev;
-		}
-		/* only send ICMP too big on first fragment */
-		if (!iph->fragoffs)
-			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
-		IP_VS_DBG_RL_PKT(0, AF_INET6, pp, skb, 0,
-				 "ip_vs_nat_xmit_v6(): frag needed for");
-		goto tx_error_put;
+		goto tx_error;
 	}
 
 	/* copy-on-write the packet before mangling it */
 	if (!skb_make_writable(skb, sizeof(struct ipv6hdr)))
-		goto tx_error_put;
+		goto tx_error;
 
 	if (skb_cow(skb, rt->dst.dev->hard_header_len))
-		goto tx_error_put;
+		goto tx_error;
 
 	/* mangle the packet */
-	if (pp->dnat_handler && !pp->dnat_handler(skb, pp, cp, iph))
+	if (pp->dnat_handler && !pp->dnat_handler(skb, pp, cp, ipvsh))
 		goto tx_error;
 	ipv6_hdr(skb)->daddr = cp->daddr.in6;
 
-	if (!local || !skb->dev) {
-		/* drop the old route when skb is not shared */
-		skb_dst_drop(skb);
-		skb_dst_set(skb, &rt->dst);
-	} else {
-		/* destined to loopback, do we need to change route? */
-		dst_release(&rt->dst);
-	}
-
 	IP_VS_DBG_PKT(10, AF_INET6, pp, skb, 0, "After DNAT");
 
 	/* FIXME: when application helper enlarges the packet and the length
@@ -776,20 +776,17 @@ ip_vs_nat_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	IP_VS_XMIT_NAT(NFPROTO_IPV6, skb, cp, local);
+	rc = ip_vs_nat_send_or_cont(NFPROTO_IPV6, skb, cp, local);
+	rcu_read_unlock();
 
 	LeaveFunction(10);
-	return NF_STOLEN;
+	return rc;
 
-tx_error_icmp:
-	dst_link_failure(skb);
 tx_error:
 	LeaveFunction(10);
 	kfree_skb(skb);
+	rcu_read_unlock();
 	return NF_STOLEN;
-tx_error_put:
-	dst_release(&rt->dst);
-	goto tx_error;
 }
 #endif
 
@@ -826,56 +823,40 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 	__be16 df;
 	struct iphdr  *iph;			/* Our new IP header */
 	unsigned int max_headroom;		/* The extra header space needed */
-	int    mtu;
-	int ret;
+	int ret, local;
 
 	EnterFunction(10);
 
-	if (!(rt = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip,
-				      RT_TOS(tos), IP_VS_RT_MODE_LOCAL |
-						   IP_VS_RT_MODE_NON_LOCAL |
-						   IP_VS_RT_MODE_CONNECT,
-						   &saddr)))
-		goto tx_error_icmp;
-	if (rt->rt_flags & RTCF_LOCAL) {
-		ip_rt_put(rt);
-		IP_VS_XMIT(NFPROTO_IPV4, skb, cp, 1);
+	rcu_read_lock();
+	local = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip,
+				   IP_VS_RT_MODE_LOCAL |
+				   IP_VS_RT_MODE_NON_LOCAL |
+				   IP_VS_RT_MODE_CONNECT |
+				   IP_VS_RT_MODE_TUNNEL, &saddr);
+	if (local < 0)
+		goto tx_error;
+	if (local) {
+		rcu_read_unlock();
+		return ip_vs_send_or_cont(NFPROTO_IPV4, skb, cp, 1);
 	}
 
+	rt = skb_rtable(skb);
 	tdev = rt->dst.dev;
 
-	mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr);
-	if (mtu < 68) {
-		IP_VS_DBG_RL("%s(): mtu less than 68\n", __func__);
-		goto tx_error_put;
-	}
-	if (rt_is_output_route(skb_rtable(skb)))
-		skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
-
 	/* Copy DF, reset fragment offset and MF */
 	df = sysctl_pmtu_disc(ipvs) ? old_iph->frag_off & htons(IP_DF) : 0;
 
-	if (df && mtu < ntohs(old_iph->tot_len) && !skb_is_gso(skb)) {
-		icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu));
-		IP_VS_DBG_RL("%s(): frag needed\n", __func__);
-		goto tx_error_put;
-	}
-
 	/*
 	 * Okay, now see if we can stuff it in the buffer as-is.
 	 */
 	max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct iphdr);
 
-	if (skb_headroom(skb) < max_headroom
-	    || skb_cloned(skb) || skb_shared(skb)) {
+	if (skb_headroom(skb) < max_headroom || skb_cloned(skb)) {
 		struct sk_buff *new_skb =
 			skb_realloc_headroom(skb, max_headroom);
-		if (!new_skb) {
-			ip_rt_put(rt);
-			kfree_skb(skb);
-			IP_VS_ERR_RL("%s(): no memory\n", __func__);
-			return NF_STOLEN;
-		}
+
+		if (!new_skb)
+			goto tx_error;
 		consume_skb(skb);
 		skb = new_skb;
 		old_iph = ip_hdr(skb);
@@ -890,10 +871,6 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 	skb_reset_network_header(skb);
 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 
-	/* drop old route */
-	skb_dst_drop(skb);
-	skb_dst_set(skb, &rt->dst);
-
 	/*
 	 *	Push down and install the IPIP header.
 	 */
@@ -911,25 +888,22 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	ret = IP_VS_XMIT_TUNNEL(skb, cp);
+	ret = ip_vs_tunnel_xmit_prepare(skb, cp);
 	if (ret == NF_ACCEPT)
 		ip_local_out(skb);
 	else if (ret == NF_DROP)
 		kfree_skb(skb);
+	rcu_read_unlock();
 
 	LeaveFunction(10);
 
 	return NF_STOLEN;
 
-  tx_error_icmp:
-	dst_link_failure(skb);
   tx_error:
 	kfree_skb(skb);
+	rcu_read_unlock();
 	LeaveFunction(10);
 	return NF_STOLEN;
-tx_error_put:
-	ip_rt_put(rt);
-	goto tx_error;
 }
 
 #ifdef CONFIG_IP_VS_IPV6
@@ -943,60 +917,37 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 	struct ipv6hdr  *old_iph = ipv6_hdr(skb);
 	struct ipv6hdr  *iph;		/* Our new IP header */
 	unsigned int max_headroom;	/* The extra header space needed */
-	int    mtu;
-	int ret;
+	int ret, local;
 
 	EnterFunction(10);
 
-	if (!(rt = __ip_vs_get_out_rt_v6(skb, cp->dest, &cp->daddr.in6,
-					 &saddr, 1, (IP_VS_RT_MODE_LOCAL |
-						     IP_VS_RT_MODE_NON_LOCAL))))
-		goto tx_error_icmp;
-	if (__ip_vs_is_local_route6(rt)) {
-		dst_release(&rt->dst);
-		IP_VS_XMIT(NFPROTO_IPV6, skb, cp, 1);
+	rcu_read_lock();
+	local = __ip_vs_get_out_rt_v6(skb, cp->dest, &cp->daddr.in6,
+				      &saddr, ipvsh, 1,
+				      IP_VS_RT_MODE_LOCAL |
+				      IP_VS_RT_MODE_NON_LOCAL |
+				      IP_VS_RT_MODE_TUNNEL);
+	if (local < 0)
+		goto tx_error;
+	if (local) {
+		rcu_read_unlock();
+		return ip_vs_send_or_cont(NFPROTO_IPV6, skb, cp, 1);
 	}
 
+	rt = (struct rt6_info *) skb_dst(skb);
 	tdev = rt->dst.dev;
 
-	mtu = dst_mtu(&rt->dst) - sizeof(struct ipv6hdr);
-	if (mtu < IPV6_MIN_MTU) {
-		IP_VS_DBG_RL("%s(): mtu less than %d\n", __func__,
-			     IPV6_MIN_MTU);
-		goto tx_error_put;
-	}
-	if (skb_dst(skb))
-		skb_dst(skb)->ops->update_pmtu(skb_dst(skb), NULL, skb, mtu);
-
-	/* MTU checking: Notice that 'mtu' have been adjusted before hand */
-	if (__mtu_check_toobig_v6(skb, mtu)) {
-		if (!skb->dev) {
-			struct net *net = dev_net(skb_dst(skb)->dev);
-
-			skb->dev = net->loopback_dev;
-		}
-		/* only send ICMP too big on first fragment */
-		if (!ipvsh->fragoffs)
-			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
-		IP_VS_DBG_RL("%s(): frag needed\n", __func__);
-		goto tx_error_put;
-	}
-
 	/*
 	 * Okay, now see if we can stuff it in the buffer as-is.
 	 */
 	max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct ipv6hdr);
 
-	if (skb_headroom(skb) < max_headroom
-	    || skb_cloned(skb) || skb_shared(skb)) {
+	if (skb_headroom(skb) < max_headroom || skb_cloned(skb)) {
 		struct sk_buff *new_skb =
 			skb_realloc_headroom(skb, max_headroom);
-		if (!new_skb) {
-			dst_release(&rt->dst);
-			kfree_skb(skb);
-			IP_VS_ERR_RL("%s(): no memory\n", __func__);
-			return NF_STOLEN;
-		}
+
+		if (!new_skb)
+			goto tx_error;
 		consume_skb(skb);
 		skb = new_skb;
 		old_iph = ipv6_hdr(skb);
@@ -1008,10 +959,6 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 	skb_reset_network_header(skb);
 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 
-	/* drop old route */
-	skb_dst_drop(skb);
-	skb_dst_set(skb, &rt->dst);
-
 	/*
 	 *	Push down and install the IPIP header.
 	 */
@@ -1029,25 +976,22 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	ret = IP_VS_XMIT_TUNNEL(skb, cp);
+	ret = ip_vs_tunnel_xmit_prepare(skb, cp);
 	if (ret == NF_ACCEPT)
 		ip6_local_out(skb);
 	else if (ret == NF_DROP)
 		kfree_skb(skb);
+	rcu_read_unlock();
 
 	LeaveFunction(10);
 
 	return NF_STOLEN;
 
-tx_error_icmp:
-	dst_link_failure(skb);
 tx_error:
 	kfree_skb(skb);
+	rcu_read_unlock();
 	LeaveFunction(10);
 	return NF_STOLEN;
-tx_error_put:
-	dst_release(&rt->dst);
-	goto tx_error;
 }
 #endif
 
@@ -1060,59 +1004,36 @@ int
 ip_vs_dr_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 	      struct ip_vs_protocol *pp, struct ip_vs_iphdr *ipvsh)
 {
-	struct rtable *rt;			/* Route to the other host */
-	struct iphdr  *iph = ip_hdr(skb);
-	int    mtu;
+	int local;
 
 	EnterFunction(10);
 
-	if (!(rt = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip,
-				      RT_TOS(iph->tos),
-				      IP_VS_RT_MODE_LOCAL |
-				      IP_VS_RT_MODE_NON_LOCAL |
-				      IP_VS_RT_MODE_KNOWN_NH, NULL)))
-		goto tx_error_icmp;
-	if (rt->rt_flags & RTCF_LOCAL) {
-		ip_rt_put(rt);
-		IP_VS_XMIT(NFPROTO_IPV4, skb, cp, 1);
-	}
-
-	/* MTU checking */
-	mtu = dst_mtu(&rt->dst);
-	if ((iph->frag_off & htons(IP_DF)) && skb->len > mtu &&
-	    !skb_is_gso(skb)) {
-		icmp_send(skb, ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED, htonl(mtu));
-		ip_rt_put(rt);
-		IP_VS_DBG_RL("%s(): frag needed\n", __func__);
+	rcu_read_lock();
+	local = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip,
+				   IP_VS_RT_MODE_LOCAL |
+				   IP_VS_RT_MODE_NON_LOCAL |
+				   IP_VS_RT_MODE_KNOWN_NH, NULL);
+	if (local < 0)
 		goto tx_error;
+	if (local) {
+		rcu_read_unlock();
+		return ip_vs_send_or_cont(NFPROTO_IPV4, skb, cp, 1);
 	}
 
-	/*
-	 * Call ip_send_check because we are not sure it is called
-	 * after ip_defrag. Is copy-on-write needed?
-	 */
-	if (unlikely((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)) {
-		ip_rt_put(rt);
-		return NF_STOLEN;
-	}
 	ip_send_check(ip_hdr(skb));
 
-	/* drop old route */
-	skb_dst_drop(skb);
-	skb_dst_set(skb, &rt->dst);
-
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	IP_VS_XMIT(NFPROTO_IPV4, skb, cp, 0);
+	ip_vs_send_or_cont(NFPROTO_IPV4, skb, cp, 0);
+	rcu_read_unlock();
 
 	LeaveFunction(10);
 	return NF_STOLEN;
 
-  tx_error_icmp:
-	dst_link_failure(skb);
   tx_error:
 	kfree_skb(skb);
+	rcu_read_unlock();
 	LeaveFunction(10);
 	return NF_STOLEN;
 }
@@ -1120,64 +1041,36 @@ ip_vs_dr_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 #ifdef CONFIG_IP_VS_IPV6
 int
 ip_vs_dr_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
-		 struct ip_vs_protocol *pp, struct ip_vs_iphdr *iph)
+		 struct ip_vs_protocol *pp, struct ip_vs_iphdr *ipvsh)
 {
-	struct rt6_info *rt;			/* Route to the other host */
-	int    mtu;
+	int local;
 
 	EnterFunction(10);
 
-	if (!(rt = __ip_vs_get_out_rt_v6(skb, cp->dest, &cp->daddr.in6, NULL,
-					 0, (IP_VS_RT_MODE_LOCAL |
-					     IP_VS_RT_MODE_NON_LOCAL))))
-		goto tx_error_icmp;
-	if (__ip_vs_is_local_route6(rt)) {
-		dst_release(&rt->dst);
-		IP_VS_XMIT(NFPROTO_IPV6, skb, cp, 1);
-	}
-
-	/* MTU checking */
-	mtu = dst_mtu(&rt->dst);
-	if (__mtu_check_toobig_v6(skb, mtu)) {
-		if (!skb->dev) {
-			struct net *net = dev_net(skb_dst(skb)->dev);
-
-			skb->dev = net->loopback_dev;
-		}
-		/* only send ICMP too big on first fragment */
-		if (!iph->fragoffs)
-			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
-		dst_release(&rt->dst);
-		IP_VS_DBG_RL("%s(): frag needed\n", __func__);
+	rcu_read_lock();
+	local = __ip_vs_get_out_rt_v6(skb, cp->dest, &cp->daddr.in6, NULL,
+				      ipvsh, 0,
+				      IP_VS_RT_MODE_LOCAL |
+				      IP_VS_RT_MODE_NON_LOCAL);
+	if (local < 0)
 		goto tx_error;
+	if (local) {
+		rcu_read_unlock();
+		return ip_vs_send_or_cont(NFPROTO_IPV6, skb, cp, 1);
 	}
 
-	/*
-	 * Call ip_send_check because we are not sure it is called
-	 * after ip_defrag. Is copy-on-write needed?
-	 */
-	skb = skb_share_check(skb, GFP_ATOMIC);
-	if (unlikely(skb == NULL)) {
-		dst_release(&rt->dst);
-		return NF_STOLEN;
-	}
-
-	/* drop old route */
-	skb_dst_drop(skb);
-	skb_dst_set(skb, &rt->dst);
-
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	IP_VS_XMIT(NFPROTO_IPV6, skb, cp, 0);
+	ip_vs_send_or_cont(NFPROTO_IPV6, skb, cp, 0);
+	rcu_read_unlock();
 
 	LeaveFunction(10);
 	return NF_STOLEN;
 
-tx_error_icmp:
-	dst_link_failure(skb);
 tx_error:
 	kfree_skb(skb);
+	rcu_read_unlock();
 	LeaveFunction(10);
 	return NF_STOLEN;
 }
@@ -1194,10 +1087,9 @@ ip_vs_icmp_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 		struct ip_vs_iphdr *iph)
 {
 	struct rtable	*rt;	/* Route to the other host */
-	int mtu;
 	int rc;
 	int local;
-	int rt_mode;
+	int rt_mode, was_input;
 
 	EnterFunction(10);
 
@@ -1217,16 +1109,17 @@ ip_vs_icmp_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 	/*
 	 * mangle and send the packet here (only for VS/NAT)
 	 */
+	was_input = rt_is_input_route(skb_rtable(skb));
 
 	/* LOCALNODE from FORWARD hook is not supported */
 	rt_mode = (hooknum != NF_INET_FORWARD) ?
 		  IP_VS_RT_MODE_LOCAL | IP_VS_RT_MODE_NON_LOCAL |
 		  IP_VS_RT_MODE_RDR : IP_VS_RT_MODE_NON_LOCAL;
-	if (!(rt = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip,
-				      RT_TOS(ip_hdr(skb)->tos),
-				      rt_mode, NULL)))
-		goto tx_error_icmp;
-	local = rt->rt_flags & RTCF_LOCAL;
+	rcu_read_lock();
+	local = __ip_vs_get_out_rt(skb, cp->dest, cp->daddr.ip, rt_mode, NULL);
+	if (local < 0)
+		goto tx_error;
+	rt = skb_rtable(skb);
 
 	/*
 	 * Avoid duplicate tuple in reply direction for NAT traffic
@@ -1241,82 +1134,51 @@ ip_vs_icmp_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 			IP_VS_DBG(10, "%s(): "
 				  "stopping DNAT to local address %pI4\n",
 				  __func__, &cp->daddr.ip);
-			goto tx_error_put;
+			goto tx_error;
 		}
 	}
 #endif
 
 	/* From world but DNAT to loopback address? */
-	if (local && ipv4_is_loopback(cp->daddr.ip) &&
-	    rt_is_input_route(skb_rtable(skb))) {
+	if (local && ipv4_is_loopback(cp->daddr.ip) && was_input) {
 		IP_VS_DBG(1, "%s(): "
 			  "stopping DNAT to loopback %pI4\n",
 			  __func__, &cp->daddr.ip);
-		goto tx_error_put;
-	}
-
-	/* MTU checking */
-	mtu = dst_mtu(&rt->dst);
-	if ((skb->len > mtu) && (ip_hdr(skb)->frag_off & htons(IP_DF)) &&
-	    !skb_is_gso(skb)) {
-		icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));
-		IP_VS_DBG_RL("%s(): frag needed\n", __func__);
-		goto tx_error_put;
+		goto tx_error;
 	}
 
 	/* copy-on-write the packet before mangling it */
 	if (!skb_make_writable(skb, offset))
-		goto tx_error_put;
+		goto tx_error;
 
 	if (skb_cow(skb, rt->dst.dev->hard_header_len))
-		goto tx_error_put;
+		goto tx_error;
 
 	ip_vs_nat_icmp(skb, pp, cp, 0);
 
-	if (!local) {
-		/* drop the old route when skb is not shared */
-		skb_dst_drop(skb);
-		skb_dst_set(skb, &rt->dst);
-	} else {
-		ip_rt_put(rt);
-		/*
-		 * Some IPv4 replies get local address from routes,
-		 * not from iph, so while we DNAT after routing
-		 * we need this second input/output route.
-		 */
-		if (!__ip_vs_reroute_locally(skb))
-			goto tx_error;
-	}
-
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	IP_VS_XMIT_NAT(NFPROTO_IPV4, skb, cp, local);
-
-	rc = NF_STOLEN;
+	rc = ip_vs_nat_send_or_cont(NFPROTO_IPV4, skb, cp, local);
+	rcu_read_unlock();
 	goto out;
 
-  tx_error_icmp:
-	dst_link_failure(skb);
   tx_error:
-	dev_kfree_skb(skb);
+	kfree_skb(skb);
+	rcu_read_unlock();
 	rc = NF_STOLEN;
   out:
 	LeaveFunction(10);
 	return rc;
-  tx_error_put:
-	ip_rt_put(rt);
-	goto tx_error;
 }
 
 #ifdef CONFIG_IP_VS_IPV6
 int
 ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 		struct ip_vs_protocol *pp, int offset, unsigned int hooknum,
-		struct ip_vs_iphdr *iph)
+		struct ip_vs_iphdr *ipvsh)
 {
 	struct rt6_info	*rt;	/* Route to the other host */
-	int mtu;
 	int rc;
 	int local;
 	int rt_mode;
@@ -1328,7 +1190,7 @@ ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 	   translate address/port back */
 	if (IP_VS_FWD_METHOD(cp) != IP_VS_CONN_F_MASQ) {
 		if (cp->packet_xmit)
-			rc = cp->packet_xmit(skb, cp, pp, iph);
+			rc = cp->packet_xmit(skb, cp, pp, ipvsh);
 		else
 			rc = NF_ACCEPT;
 		/* do not touch skb anymore */
@@ -1344,11 +1206,12 @@ ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 	rt_mode = (hooknum != NF_INET_FORWARD) ?
 		  IP_VS_RT_MODE_LOCAL | IP_VS_RT_MODE_NON_LOCAL |
 		  IP_VS_RT_MODE_RDR : IP_VS_RT_MODE_NON_LOCAL;
-	if (!(rt = __ip_vs_get_out_rt_v6(skb, cp->dest, &cp->daddr.in6, NULL,
-					 0, rt_mode)))
-		goto tx_error_icmp;
-
-	local = __ip_vs_is_local_route6(rt);
+	rcu_read_lock();
+	local = __ip_vs_get_out_rt_v6(skb, cp->dest, &cp->daddr.in6, NULL,
+				      ipvsh, 0, rt_mode);
+	if (local < 0)
+		goto tx_error;
+	rt = (struct rt6_info *) skb_dst(skb);
 	/*
 	 * Avoid duplicate tuple in reply direction for NAT traffic
 	 * to local address when connection is sync-ed
@@ -1362,7 +1225,7 @@ ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 			IP_VS_DBG(10, "%s(): "
 				  "stopping DNAT to local address %pI6\n",
 				  __func__, &cp->daddr.in6);
-			goto tx_error_put;
+			goto tx_error;
 		}
 	}
 #endif
@@ -1373,60 +1236,31 @@ ip_vs_icmp_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 		IP_VS_DBG(1, "%s(): "
 			  "stopping DNAT to loopback %pI6\n",
 			  __func__, &cp->daddr.in6);
-		goto tx_error_put;
-	}
-
-	/* MTU checking */
-	mtu = dst_mtu(&rt->dst);
-	if (__mtu_check_toobig_v6(skb, mtu)) {
-		if (!skb->dev) {
-			struct net *net = dev_net(skb_dst(skb)->dev);
-
-			skb->dev = net->loopback_dev;
-		}
-		/* only send ICMP too big on first fragment */
-		if (!iph->fragoffs)
-			icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
-		IP_VS_DBG_RL("%s(): frag needed\n", __func__);
-		goto tx_error_put;
+		goto tx_error;
 	}
 
 	/* copy-on-write the packet before mangling it */
 	if (!skb_make_writable(skb, offset))
-		goto tx_error_put;
+		goto tx_error;
 
 	if (skb_cow(skb, rt->dst.dev->hard_header_len))
-		goto tx_error_put;
+		goto tx_error;
 
 	ip_vs_nat_icmp_v6(skb, pp, cp, 0);
 
-	if (!local || !skb->dev) {
-		/* drop the old route when skb is not shared */
-		skb_dst_drop(skb);
-		skb_dst_set(skb, &rt->dst);
-	} else {
-		/* destined to loopback, do we need to change route? */
-		dst_release(&rt->dst);
-	}
-
 	/* Another hack: avoid icmp_send in ip_fragment */
 	skb->local_df = 1;
 
-	IP_VS_XMIT_NAT(NFPROTO_IPV6, skb, cp, local);
-
-	rc = NF_STOLEN;
+	rc = ip_vs_nat_send_or_cont(NFPROTO_IPV6, skb, cp, local);
+	rcu_read_unlock();
 	goto out;
 
-tx_error_icmp:
-	dst_link_failure(skb);
 tx_error:
-	dev_kfree_skb(skb);
+	kfree_skb(skb);
+	rcu_read_unlock();
 	rc = NF_STOLEN;
 out:
 	LeaveFunction(10);
 	return rc;
-tx_error_put:
-	dst_release(&rt->dst);
-	goto tx_error;
 }
 #endif