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diff -urN linux-2.6.19.old/include/linux/netfilter_ipv4/ip_nat.h linux-2.6.19.dev/include/linux/netfilter_ipv4/ip_nat.h
--- linux-2.6.19.old/include/linux/netfilter_ipv4/ip_nat.h	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/include/linux/netfilter_ipv4/ip_nat.h	2006-12-14 03:13:53.000000000 +0100
@@ -63,6 +63,13 @@
 
 struct ip_conntrack;
 
+/* Call input routing for SNAT-ed traffic */
+extern unsigned int ip_nat_route_input(unsigned int hooknum,
+				       struct sk_buff **pskb,
+				       const struct net_device *in,
+				       const struct net_device *out,
+				       int (*okfn)(struct sk_buff *));
+
 /* Set up the info structure to map into this range. */
 extern unsigned int ip_nat_setup_info(struct ip_conntrack *conntrack,
 				      const struct ip_nat_range *range,
diff -urN linux-2.6.19.old/include/linux/rtnetlink.h linux-2.6.19.dev/include/linux/rtnetlink.h
--- linux-2.6.19.old/include/linux/rtnetlink.h	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/include/linux/rtnetlink.h	2006-12-14 03:13:53.000000000 +0100
@@ -293,6 +293,8 @@
 #define RTNH_F_DEAD		1	/* Nexthop is dead (used by multipath)	*/
 #define RTNH_F_PERVASIVE	2	/* Do recursive gateway lookup	*/
 #define RTNH_F_ONLINK		4	/* Gateway is forced on link	*/
+#define RTNH_F_SUSPECT		8	/* We don't know the real state	*/
+#define RTNH_F_BADSTATE		(RTNH_F_DEAD | RTNH_F_SUSPECT)
 
 /* Macros to handle hexthops */
 
diff -urN linux-2.6.19.old/include/net/flow.h linux-2.6.19.dev/include/net/flow.h
--- linux-2.6.19.old/include/net/flow.h	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/include/net/flow.h	2006-12-14 03:13:53.000000000 +0100
@@ -19,6 +19,8 @@
 			__be32			daddr;
 			__be32			saddr;
 			__u32			fwmark;
+			__u32			lsrc;
+			__u32			gw;
 			__u8			tos;
 			__u8			scope;
 		} ip4_u;
@@ -48,6 +50,8 @@
 #define fl4_dst		nl_u.ip4_u.daddr
 #define fl4_src		nl_u.ip4_u.saddr
 #define fl4_fwmark	nl_u.ip4_u.fwmark
+#define fl4_lsrc	nl_u.ip4_u.lsrc
+#define fl4_gw		nl_u.ip4_u.gw
 #define fl4_tos		nl_u.ip4_u.tos
 #define fl4_scope	nl_u.ip4_u.scope
 
diff -urN linux-2.6.19.old/include/net/ip_fib.h linux-2.6.19.dev/include/net/ip_fib.h
--- linux-2.6.19.old/include/net/ip_fib.h	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/include/net/ip_fib.h	2006-12-14 03:13:53.000000000 +0100
@@ -196,7 +196,8 @@
 
 static inline void fib_select_default(const struct flowi *flp, struct fib_result *res)
 {
-	if (FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
+	if ((FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) ||
+	    FIB_RES_NH(*res).nh_scope == RT_SCOPE_HOST)
 		ip_fib_main_table->tb_select_default(ip_fib_main_table, flp, res);
 }
 
@@ -212,6 +213,8 @@
 
 #endif /* CONFIG_IP_MULTIPLE_TABLES */
 
+extern int fib_result_table(struct fib_result *res);
+
 /* Exported by fib_frontend.c */
 extern struct nla_policy rtm_ipv4_policy[];
 extern void		ip_fib_init(void);
@@ -284,4 +287,6 @@
 extern void fib_proc_exit(void);
 #endif
 
+extern rwlock_t fib_nhflags_lock;
+
 #endif  /* _NET_FIB_H */
diff -urN linux-2.6.19.old/include/net/route.h linux-2.6.19.dev/include/net/route.h
--- linux-2.6.19.old/include/net/route.h	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/include/net/route.h	2006-12-14 03:13:53.000000000 +0100
@@ -117,6 +117,7 @@
 extern int		ip_route_output_key(struct rtable **, struct flowi *flp);
 extern int		ip_route_output_flow(struct rtable **rp, struct flowi *flp, struct sock *sk, int flags);
 extern int		ip_route_input(struct sk_buff*, __be32 dst, __be32 src, u8 tos, struct net_device *devin);
+extern int		ip_route_input_lookup(struct sk_buff*, u32 dst, u32 src, u8 tos, struct net_device *devin, u32 lsrc);
 extern unsigned short	ip_rt_frag_needed(struct iphdr *iph, unsigned short new_mtu);
 extern void		ip_rt_send_redirect(struct sk_buff *skb);
 
diff -urN linux-2.6.19.old/net/ipv4/fib_frontend.c linux-2.6.19.dev/net/ipv4/fib_frontend.c
--- linux-2.6.19.old/net/ipv4/fib_frontend.c	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/net/ipv4/fib_frontend.c	2006-12-14 03:13:53.000000000 +0100
@@ -58,6 +58,8 @@
 #define FIB_TABLE_HASHSZ 1
 static struct hlist_head fib_table_hash[FIB_TABLE_HASHSZ];
 
+#define FIB_RES_TABLE(r) (RT_TABLE_MAIN)
+
 #else
 
 #define FIB_TABLE_HASHSZ 256
@@ -100,6 +102,9 @@
 	rcu_read_unlock();
 	return NULL;
 }
+
+#define FIB_RES_TABLE(r) (fib_result_table(r))
+
 #endif /* CONFIG_IP_MULTIPLE_TABLES */
 
 static void fib_flush(void)
@@ -190,6 +195,9 @@
 					.tos = tos } },
 			    .iif = oif };
 	struct fib_result res;
+	int table;
+	unsigned char prefixlen;
+	unsigned char scope;
 	int no_addr, rpf;
 	int ret;
 
@@ -211,31 +219,35 @@
 		goto e_inval_res;
 	*spec_dst = FIB_RES_PREFSRC(res);
 	fib_combine_itag(itag, &res);
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
-	if (FIB_RES_DEV(res) == dev || res.fi->fib_nhs > 1)
-#else
 	if (FIB_RES_DEV(res) == dev)
-#endif
 	{
 		ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
 		fib_res_put(&res);
 		return ret;
 	}
+	table = FIB_RES_TABLE(&res);
+	prefixlen = res.prefixlen;
+	scope = res.scope;
 	fib_res_put(&res);
 	if (no_addr)
 		goto last_resort;
-	if (rpf)
-		goto e_inval;
 	fl.oif = dev->ifindex;
 
 	ret = 0;
 	if (fib_lookup(&fl, &res) == 0) {
-		if (res.type == RTN_UNICAST) {
+		if (res.type == RTN_UNICAST &&
+		    ((table == FIB_RES_TABLE(&res) &&
+		      res.prefixlen >= prefixlen && res.scope >= scope) ||
+		     !rpf)) {
 			*spec_dst = FIB_RES_PREFSRC(res);
 			ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
+			fib_res_put(&res);
+			return ret;
 		}
 		fib_res_put(&res);
 	}
+	if (rpf)
+		goto e_inval;
 	return ret;
 
 last_resort:
@@ -836,9 +848,7 @@
 	switch (event) {
 	case NETDEV_UP:
 		fib_add_ifaddr(ifa);
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
 		fib_sync_up(ifa->ifa_dev->dev);
-#endif
 		rt_cache_flush(-1);
 		break;
 	case NETDEV_DOWN:
@@ -874,9 +884,7 @@
 		for_ifa(in_dev) {
 			fib_add_ifaddr(ifa);
 		} endfor_ifa(in_dev);
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
 		fib_sync_up(dev);
-#endif
 		rt_cache_flush(-1);
 		break;
 	case NETDEV_DOWN:
diff -urN linux-2.6.19.old/net/ipv4/fib_hash.c linux-2.6.19.dev/net/ipv4/fib_hash.c
--- linux-2.6.19.old/net/ipv4/fib_hash.c	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/net/ipv4/fib_hash.c	2006-12-14 03:13:53.000000000 +0100
@@ -275,30 +275,38 @@
 	return err;
 }
 
-static int fn_hash_last_dflt=-1;
-
 static void
 fn_hash_select_default(struct fib_table *tb, const struct flowi *flp, struct fib_result *res)
 {
-	int order, last_idx;
+	int order, last_idx, last_dflt, last_nhsel;
+	struct fib_alias *first_fa = NULL;
+	struct hlist_head *head;
 	struct hlist_node *node;
 	struct fib_node *f;
 	struct fib_info *fi = NULL;
 	struct fib_info *last_resort;
 	struct fn_hash *t = (struct fn_hash*)tb->tb_data;
-	struct fn_zone *fz = t->fn_zones[0];
+	struct fn_zone *fz = t->fn_zones[res->prefixlen];
+	u32 k;
 
 	if (fz == NULL)
 		return;
 
+	k = fz_key(flp->fl4_dst, fz);
+	last_dflt = -2;
+	last_nhsel = 0;
 	last_idx = -1;
 	last_resort = NULL;
 	order = -1;
 
 	read_lock(&fib_hash_lock);
-	hlist_for_each_entry(f, node, &fz->fz_hash[0], fn_hash) {
+	head = &fz->fz_hash[fn_hash(k, fz)];
+	hlist_for_each_entry(f, node, head, fn_hash) {
 		struct fib_alias *fa;
 
+		if (f->fn_key != k)
+			continue;
+
 		list_for_each_entry(fa, &f->fn_alias, fa_list) {
 			struct fib_info *next_fi = fa->fa_info;
 
@@ -306,41 +314,52 @@
 			    fa->fa_type != RTN_UNICAST)
 				continue;
 
+			if (fa->fa_tos &&
+			    fa->fa_tos != flp->fl4_tos)
+				continue;
 			if (next_fi->fib_priority > res->fi->fib_priority)
 				break;
-			if (!next_fi->fib_nh[0].nh_gw ||
-			    next_fi->fib_nh[0].nh_scope != RT_SCOPE_LINK)
-				continue;
 			fa->fa_state |= FA_S_ACCESSED;
 
-			if (fi == NULL) {
-				if (next_fi != res->fi)
-					break;
-			} else if (!fib_detect_death(fi, order, &last_resort,
-						     &last_idx, &fn_hash_last_dflt)) {
+			if (!first_fa) {
+				last_dflt = fa->fa_last_dflt;
+				first_fa = fa;
+			}
+			if (fi && !fib_detect_death(fi, order, &last_resort,
+				&last_idx, &last_dflt, &last_nhsel, flp)) {
 				if (res->fi)
 					fib_info_put(res->fi);
 				res->fi = fi;
 				atomic_inc(&fi->fib_clntref);
-				fn_hash_last_dflt = order;
+				first_fa->fa_last_dflt = order;
 				goto out;
 			}
 			fi = next_fi;
 			order++;
 		}
+		break;
 	}
 
 	if (order <= 0 || fi == NULL) {
-		fn_hash_last_dflt = -1;
+		if (fi && fi->fib_nhs > 1 &&
+		    fib_detect_death(fi, order, &last_resort, &last_idx,
+			&last_dflt, &last_nhsel, flp) &&
+		    last_resort == fi) {
+			read_lock_bh(&fib_nhflags_lock);
+			fi->fib_nh[last_nhsel].nh_flags &= ~RTNH_F_SUSPECT;
+			read_unlock_bh(&fib_nhflags_lock);
+		}
+		if (first_fa) first_fa->fa_last_dflt = -1;
 		goto out;
 	}
 
-	if (!fib_detect_death(fi, order, &last_resort, &last_idx, &fn_hash_last_dflt)) {
+	if (!fib_detect_death(fi, order, &last_resort, &last_idx,
+			      &last_dflt, &last_nhsel, flp)) {
 		if (res->fi)
 			fib_info_put(res->fi);
 		res->fi = fi;
 		atomic_inc(&fi->fib_clntref);
-		fn_hash_last_dflt = order;
+		first_fa->fa_last_dflt = order;
 		goto out;
 	}
 
@@ -350,8 +369,11 @@
 		res->fi = last_resort;
 		if (last_resort)
 			atomic_inc(&last_resort->fib_clntref);
+		read_lock_bh(&fib_nhflags_lock);
+		last_resort->fib_nh[last_nhsel].nh_flags &= ~RTNH_F_SUSPECT;
+		read_unlock_bh(&fib_nhflags_lock);
+		first_fa->fa_last_dflt = last_idx;
 	}
-	fn_hash_last_dflt = last_idx;
 out:
 	read_unlock(&fib_hash_lock);
 }
@@ -447,6 +469,7 @@
 			write_lock_bh(&fib_hash_lock);
 			fi_drop = fa->fa_info;
 			fa->fa_info = fi;
+			fa->fa_last_dflt = -1;
 			fa->fa_type = cfg->fc_type;
 			fa->fa_scope = cfg->fc_scope;
 			state = fa->fa_state;
@@ -506,6 +529,7 @@
 	new_fa->fa_type = cfg->fc_type;
 	new_fa->fa_scope = cfg->fc_scope;
 	new_fa->fa_state = 0;
+	new_fa->fa_last_dflt = -1;
 
 	/*
 	 * Insert new entry to the list.
diff -urN linux-2.6.19.old/net/ipv4/fib_lookup.h linux-2.6.19.dev/net/ipv4/fib_lookup.h
--- linux-2.6.19.old/net/ipv4/fib_lookup.h	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/net/ipv4/fib_lookup.h	2006-12-14 03:13:53.000000000 +0100
@@ -9,6 +9,7 @@
 	struct list_head	fa_list;
 	struct rcu_head rcu;
 	struct fib_info		*fa_info;
+	int			fa_last_dflt;
 	u8			fa_tos;
 	u8			fa_type;
 	u8			fa_scope;
@@ -35,6 +36,7 @@
 					u8 tos, u32 prio);
 extern int fib_detect_death(struct fib_info *fi, int order,
 			    struct fib_info **last_resort,
-			    int *last_idx, int *dflt);
+			    int *last_idx, int *dflt, int *last_nhsel,
+			    const struct flowi *flp);
 
 #endif /* _FIB_LOOKUP_H */
diff -urN linux-2.6.19.old/net/ipv4/fib_rules.c linux-2.6.19.dev/net/ipv4/fib_rules.c
--- linux-2.6.19.old/net/ipv4/fib_rules.c	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/net/ipv4/fib_rules.c	2006-12-14 03:13:53.000000000 +0100
@@ -89,6 +89,11 @@
 }
 #endif
 
+int fib_result_table(struct fib_result *res)
+{
+	return res->r->table;
+}
+
 int fib_lookup(struct flowi *flp, struct fib_result *res)
 {
 	struct fib_lookup_arg arg = {
@@ -140,7 +145,8 @@
 void fib_select_default(const struct flowi *flp, struct fib_result *res)
 {
 	if (res->r && res->r->action == FR_ACT_TO_TBL &&
-	    FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) {
+	    ((FIB_RES_GW(*res) && FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK) ||
+	      FIB_RES_NH(*res).nh_scope == RT_SCOPE_HOST)) {
 		struct fib_table *tb;
 		if ((tb = fib_get_table(res->r->table)) != NULL)
 			tb->tb_select_default(tb, flp, res);
diff -urN linux-2.6.19.old/net/ipv4/fib_semantics.c linux-2.6.19.dev/net/ipv4/fib_semantics.c
--- linux-2.6.19.old/net/ipv4/fib_semantics.c	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/net/ipv4/fib_semantics.c	2006-12-14 03:13:53.000000000 +0100
@@ -55,6 +55,7 @@
 static struct hlist_head *fib_info_laddrhash;
 static unsigned int fib_hash_size;
 static unsigned int fib_info_cnt;
+rwlock_t fib_nhflags_lock = RW_LOCK_UNLOCKED;
 
 #define DEVINDEX_HASHBITS 8
 #define DEVINDEX_HASHSIZE (1U << DEVINDEX_HASHBITS)
@@ -190,7 +191,7 @@
 #ifdef CONFIG_NET_CLS_ROUTE
 		    nh->nh_tclassid != onh->nh_tclassid ||
 #endif
-		    ((nh->nh_flags^onh->nh_flags)&~RTNH_F_DEAD))
+		    ((nh->nh_flags^onh->nh_flags)&~RTNH_F_BADSTATE))
 			return -1;
 		onh++;
 	} endfor_nexthops(fi);
@@ -227,7 +228,7 @@
 		    nfi->fib_priority == fi->fib_priority &&
 		    memcmp(nfi->fib_metrics, fi->fib_metrics,
 			   sizeof(fi->fib_metrics)) == 0 &&
-		    ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_DEAD) == 0 &&
+		    ((nfi->fib_flags^fi->fib_flags)&~RTNH_F_BADSTATE) == 0 &&
 		    (nfi->fib_nhs == 0 || nh_comp(fi, nfi) == 0))
 			return fi;
 	}
@@ -319,26 +320,70 @@
 }
 
 int fib_detect_death(struct fib_info *fi, int order,
-		     struct fib_info **last_resort, int *last_idx, int *dflt)
+		     struct fib_info **last_resort, int *last_idx, int *dflt,
+		     int *last_nhsel, const struct flowi *flp)
 {
 	struct neighbour *n;
-	int state = NUD_NONE;
+	int nhsel;
+	int state;
+	struct fib_nh * nh;
+	u32 dst;
+	int flag, dead = 1;
+
+	/* change_nexthops(fi) { */
+	for (nhsel = 0, nh = fi->fib_nh; nhsel < fi->fib_nhs; nh++, nhsel++) {
+		if (flp->oif && flp->oif != nh->nh_oif)
+			continue;
+		if (flp->fl4_gw && flp->fl4_gw != nh->nh_gw && nh->nh_gw &&
+		    nh->nh_scope == RT_SCOPE_LINK)
+			continue;
+		if (nh->nh_flags & RTNH_F_DEAD)
+			continue;
 
-	n = neigh_lookup(&arp_tbl, &fi->fib_nh[0].nh_gw, fi->fib_dev);
-	if (n) {
-		state = n->nud_state;
-		neigh_release(n);
-	}
-	if (state==NUD_REACHABLE)
-		return 0;
-	if ((state&NUD_VALID) && order != *dflt)
-		return 0;
-	if ((state&NUD_VALID) ||
-	    (*last_idx<0 && order > *dflt)) {
-		*last_resort = fi;
-		*last_idx = order;
+		flag = 0;
+		if (nh->nh_dev->flags & IFF_NOARP) {
+			dead = 0;
+			goto setfl;
+		}
+
+		dst = nh->nh_gw;
+		if (!nh->nh_gw || nh->nh_scope != RT_SCOPE_LINK)
+			dst = flp->fl4_dst;
+
+		state = NUD_NONE;
+		n = neigh_lookup(&arp_tbl, &dst, nh->nh_dev);
+		if (n) {
+			state = n->nud_state;
+			neigh_release(n);
+		}
+		if (state==NUD_REACHABLE ||
+			((state&NUD_VALID) && order != *dflt)) {
+			dead = 0;
+			goto setfl;
+		}
+		if (!(state&NUD_VALID))
+			flag = 1;
+		if (!dead)
+			goto setfl;
+		if ((state&NUD_VALID) ||
+		    (*last_idx<0 && order >= *dflt)) {
+			*last_resort = fi;
+			*last_idx = order;
+			*last_nhsel = nhsel;
+		}
+
+		setfl:
+
+		read_lock_bh(&fib_nhflags_lock);
+		if (flag)
+			nh->nh_flags |= RTNH_F_SUSPECT;
+		else
+			nh->nh_flags &= ~RTNH_F_SUSPECT;
+		read_unlock_bh(&fib_nhflags_lock);
 	}
-	return 1;
+	/* } endfor_nexthops(fi) */
+
+	return dead;
 }
 
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
@@ -508,8 +553,11 @@
 				return -EINVAL;
 			if ((dev = __dev_get_by_index(nh->nh_oif)) == NULL)
 				return -ENODEV;
-			if (!(dev->flags&IFF_UP))
-				return -ENETDOWN;
+			if (!(dev->flags&IFF_UP)) {
+				if (fi->fib_protocol != RTPROT_STATIC)
+					return -ENETDOWN;
+				nh->nh_flags |= RTNH_F_DEAD;
+			}
 			nh->nh_dev = dev;
 			dev_hold(dev);
 			nh->nh_scope = RT_SCOPE_LINK;
@@ -529,24 +577,48 @@
 			/* It is not necessary, but requires a bit of thinking */
 			if (fl.fl4_scope < RT_SCOPE_LINK)
 				fl.fl4_scope = RT_SCOPE_LINK;
-			if ((err = fib_lookup(&fl, &res)) != 0)
-				return err;
+			err = fib_lookup(&fl, &res);
 		}
-		err = -EINVAL;
-		if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
-			goto out;
-		nh->nh_scope = res.scope;
-		nh->nh_oif = FIB_RES_OIF(res);
-		if ((nh->nh_dev = FIB_RES_DEV(res)) == NULL)
-			goto out;
-		dev_hold(nh->nh_dev);
-		err = -ENETDOWN;
-		if (!(nh->nh_dev->flags & IFF_UP))
-			goto out;
-		err = 0;
+		if (err) {
+			struct in_device *in_dev;
+
+			if (err != -ENETUNREACH ||
+			    fi->fib_protocol != RTPROT_STATIC)
+				return err;
+
+			in_dev = inetdev_by_index(nh->nh_oif);
+			if (in_dev == NULL ||
+			    in_dev->dev->flags & IFF_UP) {
+				if (in_dev)
+					in_dev_put(in_dev);
+				return err;
+			}
+			nh->nh_flags |= RTNH_F_DEAD;
+			nh->nh_scope = RT_SCOPE_LINK;
+			nh->nh_dev = in_dev->dev;
+			dev_hold(nh->nh_dev);
+			in_dev_put(in_dev);
+		} else {
+			err = -EINVAL;
+			if (res.type != RTN_UNICAST && res.type != RTN_LOCAL)
+				goto out;
+			nh->nh_scope = res.scope;
+			nh->nh_oif = FIB_RES_OIF(res);
+			if ((nh->nh_dev = FIB_RES_DEV(res)) == NULL)
+				goto out;
+			dev_hold(nh->nh_dev);
+			if (!(nh->nh_dev->flags & IFF_UP)) {
+				if (fi->fib_protocol != RTPROT_STATIC) {
+					err = -ENETDOWN;
+					goto out;
+				}
+				nh->nh_flags |= RTNH_F_DEAD;
+			}
+			err = 0;
 out:
-		fib_res_put(&res);
-		return err;
+			fib_res_put(&res);
+			return err;
+		}
 	} else {
 		struct in_device *in_dev;
 
@@ -557,8 +629,11 @@
 		if (in_dev == NULL)
 			return -ENODEV;
 		if (!(in_dev->dev->flags&IFF_UP)) {
-			in_dev_put(in_dev);
-			return -ENETDOWN;
+			if (fi->fib_protocol != RTPROT_STATIC) {
+				in_dev_put(in_dev);
+				return -ENETDOWN;
+			}
+			nh->nh_flags |= RTNH_F_DEAD;
 		}
 		nh->nh_dev = in_dev->dev;
 		dev_hold(nh->nh_dev);
@@ -881,8 +956,12 @@
 				for_nexthops(fi) {
 					if (nh->nh_flags&RTNH_F_DEAD)
 						continue;
-					if (!flp->oif || flp->oif == nh->nh_oif)
-						break;
+					if (flp->oif && flp->oif != nh->nh_oif)
+						continue;
+					if (flp->fl4_gw && flp->fl4_gw != nh->nh_gw &&
+					    nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK)
+						continue;
+					break;
 				}
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 				if (nhsel < fi->fib_nhs) {
@@ -1056,18 +1135,29 @@
 			prev_fi = fi;
 			dead = 0;
 			change_nexthops(fi) {
-				if (nh->nh_flags&RTNH_F_DEAD)
-					dead++;
-				else if (nh->nh_dev == dev &&
-					 nh->nh_scope != scope) {
-					nh->nh_flags |= RTNH_F_DEAD;
+				if (nh->nh_flags&RTNH_F_DEAD) {
+					if (fi->fib_protocol!=RTPROT_STATIC ||
+					    nh->nh_dev == NULL ||
+					    __in_dev_get_rtnl(nh->nh_dev) == NULL ||
+					    nh->nh_dev->flags&IFF_UP)
+						dead++;
+				} else if (nh->nh_dev == dev &&
+					   nh->nh_scope != scope) {
+					write_lock_bh(&fib_nhflags_lock);
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
-					spin_lock_bh(&fib_multipath_lock);
+					spin_lock(&fib_multipath_lock);
+					nh->nh_flags |= RTNH_F_DEAD;
 					fi->fib_power -= nh->nh_power;
 					nh->nh_power = 0;
-					spin_unlock_bh(&fib_multipath_lock);
+					spin_unlock(&fib_multipath_lock);
+#else
+					nh->nh_flags |= RTNH_F_DEAD;
 #endif
-					dead++;
+					write_unlock_bh(&fib_nhflags_lock);
+					if (fi->fib_protocol!=RTPROT_STATIC ||
+					    force ||
+					    __in_dev_get_rtnl(dev) == NULL)
+						dead++;
 				}
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 				if (force > 1 && nh->nh_dev == dev) {
@@ -1086,11 +1176,8 @@
 	return ret;
 }
 
-#ifdef CONFIG_IP_ROUTE_MULTIPATH
-
 /*
-   Dead device goes up. We wake up dead nexthops.
-   It takes sense only on multipath routes.
+   Dead device goes up or new address is added. We wake up dead nexthops.
  */
 
 int fib_sync_up(struct net_device *dev)
@@ -1100,8 +1187,10 @@
 	struct hlist_head *head;
 	struct hlist_node *node;
 	struct fib_nh *nh;
-	int ret;
+	struct fib_result res;
+	int ret, rep;
 
+repeat:
 	if (!(dev->flags&IFF_UP))
 		return 0;
 
@@ -1109,6 +1198,7 @@
 	hash = fib_devindex_hashfn(dev->ifindex);
 	head = &fib_info_devhash[hash];
 	ret = 0;
+	rep = 0;
 
 	hlist_for_each_entry(nh, node, head, nh_hash) {
 		struct fib_info *fi = nh->nh_parent;
@@ -1121,19 +1211,37 @@
 		prev_fi = fi;
 		alive = 0;
 		change_nexthops(fi) {
-			if (!(nh->nh_flags&RTNH_F_DEAD)) {
-				alive++;
+			if (!(nh->nh_flags&RTNH_F_DEAD))
 				continue;
-			}
 			if (nh->nh_dev == NULL || !(nh->nh_dev->flags&IFF_UP))
 				continue;
 			if (nh->nh_dev != dev || !__in_dev_get_rtnl(dev))
 				continue;
+			if (nh->nh_gw && fi->fib_protocol == RTPROT_STATIC) {
+				struct flowi fl = {
+					.nl_u = { .ip4_u =
+						  { .daddr = nh->nh_gw,
+						    .scope = nh->nh_scope } },
+					.oif =  nh->nh_oif,
+				};
+				if (fib_lookup(&fl, &res) != 0)
+					continue;
+				if (res.type != RTN_UNICAST &&
+				    res.type != RTN_LOCAL) {
+					fib_res_put(&res);
+					continue;
+				}
+				nh->nh_scope = res.scope;
+				fib_res_put(&res);
+				rep = 1;
+			}
 			alive++;
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
 			spin_lock_bh(&fib_multipath_lock);
 			nh->nh_power = 0;
 			nh->nh_flags &= ~RTNH_F_DEAD;
 			spin_unlock_bh(&fib_multipath_lock);
+#endif
 		} endfor_nexthops(fi)
 
 		if (alive > 0) {
@@ -1141,10 +1249,14 @@
 			ret++;
 		}
 	}
+	if (rep)
+		goto repeat;
 
 	return ret;
 }
 
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+
 /*
    The algorithm is suboptimal, but it provides really
    fair weighted route distribution.
@@ -1153,24 +1265,45 @@
 void fib_select_multipath(const struct flowi *flp, struct fib_result *res)
 {
 	struct fib_info *fi = res->fi;
-	int w;
+	int w, alive;
 
 	spin_lock_bh(&fib_multipath_lock);
+	if (flp->oif) {
+		int sel = -1;
+		w = -1;
+		change_nexthops(fi) {
+			if (flp->oif != nh->nh_oif)
+				continue;
+			if (flp->fl4_gw && flp->fl4_gw != nh->nh_gw &&
+			    nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK)
+				continue;
+			if (!(nh->nh_flags&RTNH_F_BADSTATE)) {
+				if (nh->nh_power > w) {
+					w = nh->nh_power;
+					sel = nhsel;
+				}
+			}
+		} endfor_nexthops(fi);
+		if (sel >= 0) {
+			spin_unlock_bh(&fib_multipath_lock);
+			res->nh_sel = sel;
+			return;
+		}
+		goto last_resort;
+	}
+
+repeat:
 	if (fi->fib_power <= 0) {
 		int power = 0;
 		change_nexthops(fi) {
-			if (!(nh->nh_flags&RTNH_F_DEAD)) {
+			if (!(nh->nh_flags&RTNH_F_BADSTATE)) {
 				power += nh->nh_weight;
 				nh->nh_power = nh->nh_weight;
 			}
 		} endfor_nexthops(fi);
 		fi->fib_power = power;
-		if (power <= 0) {
-			spin_unlock_bh(&fib_multipath_lock);
-			/* Race condition: route has just become dead. */
-			res->nh_sel = 0;
-			return;
-		}
+		if (power <= 0)
+			goto last_resort;
 	}
 
 
@@ -1180,20 +1313,40 @@
 
 	w = jiffies % fi->fib_power;
 
+	alive = 0;
 	change_nexthops(fi) {
-		if (!(nh->nh_flags&RTNH_F_DEAD) && nh->nh_power) {
+		if (!(nh->nh_flags&RTNH_F_BADSTATE) && nh->nh_power) {
 			if ((w -= nh->nh_power) <= 0) {
 				nh->nh_power--;
 				fi->fib_power--;
-				res->nh_sel = nhsel;
 				spin_unlock_bh(&fib_multipath_lock);
+				res->nh_sel = nhsel;
 				return;
 			}
+			alive = 1;
+		}
+	} endfor_nexthops(fi);
+	if (alive) {
+		fi->fib_power = 0;
+		goto repeat;
+	}
+
+last_resort:
+
+	for_nexthops(fi) {
+		if (!(nh->nh_flags&RTNH_F_DEAD)) {
+			if (flp->oif && flp->oif != nh->nh_oif)
+				continue;
+			if (flp->fl4_gw && flp->fl4_gw != nh->nh_gw &&
+			    nh->nh_gw && nh->nh_scope == RT_SCOPE_LINK)
+				continue;
+			spin_unlock_bh(&fib_multipath_lock);
+			res->nh_sel = nhsel;
+			return;
 		}
 	} endfor_nexthops(fi);
 
 	/* Race condition: route has just become dead. */
-	res->nh_sel = 0;
 	spin_unlock_bh(&fib_multipath_lock);
 }
 #endif
diff -urN linux-2.6.19.old/net/ipv4/netfilter/ip_nat_core.c linux-2.6.19.dev/net/ipv4/netfilter/ip_nat_core.c
--- linux-2.6.19.old/net/ipv4/netfilter/ip_nat_core.c	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/net/ipv4/netfilter/ip_nat_core.c	2006-12-14 03:13:53.000000000 +0100
@@ -573,6 +573,53 @@
 EXPORT_SYMBOL_GPL(ip_nat_port_range_to_nfattr);
 #endif
 
+unsigned int
+ip_nat_route_input(unsigned int hooknum,
+		struct sk_buff **pskb,
+		const struct net_device *in,
+		const struct net_device *out,
+		int (*okfn)(struct sk_buff *))
+{
+	struct sk_buff *skb = *pskb;
+	struct iphdr *iph;
+	struct ip_conntrack *conn;
+	enum ip_conntrack_info ctinfo;
+	enum ip_conntrack_dir dir;
+	unsigned long statusbit;
+	u32 saddr;
+
+	if (!(conn = ip_conntrack_get(skb, &ctinfo)))
+		return NF_ACCEPT;
+
+	if (!(conn->status & IPS_NAT_DONE_MASK))
+		return NF_ACCEPT;
+	dir = CTINFO2DIR(ctinfo);
+	statusbit = IPS_SRC_NAT;
+	if (dir == IP_CT_DIR_REPLY)
+		statusbit ^= IPS_NAT_MASK;
+	if (!(conn->status & statusbit))
+		return NF_ACCEPT;
+
+	if (skb->dst)
+		return NF_ACCEPT;
+
+	if (skb->len < sizeof(struct iphdr))
+		return NF_ACCEPT;
+
+	/* use daddr in other direction as masquerade address (lsrc) */
+	iph = skb->nh.iph;
+	saddr = conn->tuplehash[!dir].tuple.dst.ip;
+	if (saddr == iph->saddr)
+		return NF_ACCEPT;
+
+	if (ip_route_input_lookup(skb, iph->daddr, iph->saddr, iph->tos,
+	    skb->dev, saddr))
+		return NF_DROP;
+
+	return NF_ACCEPT;
+}
+EXPORT_SYMBOL_GPL(ip_nat_route_input);
+
 static int __init ip_nat_init(void)
 {
 	size_t i;
diff -urN linux-2.6.19.old/net/ipv4/netfilter/ip_nat_standalone.c linux-2.6.19.dev/net/ipv4/netfilter/ip_nat_standalone.c
--- linux-2.6.19.old/net/ipv4/netfilter/ip_nat_standalone.c	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/net/ipv4/netfilter/ip_nat_standalone.c	2006-12-14 03:13:53.000000000 +0100
@@ -325,6 +325,14 @@
 		.hooknum	= NF_IP_LOCAL_OUT,
 		.priority	= NF_IP_PRI_NAT_DST,
 	},
+	/* Before routing, route before mangling */
+	{
+		.hook		= ip_nat_route_input,
+		.owner		= THIS_MODULE,
+		.pf		= PF_INET,
+		.hooknum	= NF_IP_PRE_ROUTING,
+		.priority	= NF_IP_PRI_LAST-1,
+	},
 	/* After packet filtering, change source */
 	{
 		.hook		= ip_nat_fn,
diff -urN linux-2.6.19.old/net/ipv4/netfilter/ipt_MASQUERADE.c linux-2.6.19.dev/net/ipv4/netfilter/ipt_MASQUERADE.c
--- linux-2.6.19.old/net/ipv4/netfilter/ipt_MASQUERADE.c	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/net/ipv4/netfilter/ipt_MASQUERADE.c	2006-12-14 03:13:53.000000000 +0100
@@ -85,13 +85,31 @@
 		return NF_ACCEPT;
 
 	mr = targinfo;
-	rt = (struct rtable *)(*pskb)->dst;
-	newsrc = inet_select_addr(out, rt->rt_gateway, RT_SCOPE_UNIVERSE);
-	if (!newsrc) {
-		printk("MASQUERADE: %s ate my IP address\n", out->name);
-		return NF_DROP;
+
+	{
+		struct flowi fl = { .nl_u = { .ip4_u =
+					      { .daddr = (*pskb)->nh.iph->daddr,
+						.tos = (RT_TOS((*pskb)->nh.iph->tos) |
+							RTO_CONN),
+						.gw = ((struct rtable *) (*pskb)->dst)->rt_gateway,
+#ifdef CONFIG_IP_ROUTE_FWMARK
+						.fwmark = (*pskb)->nfmark
+#endif
+					      } },
+				    .oif = out->ifindex };
+		if (ip_route_output_key(&rt, &fl) != 0) {
+			/* Funky routing can do this. */
+			if (net_ratelimit())
+				printk("MASQUERADE:"
+				       " No route: Rusty's brain broke!\n");
+			return NF_DROP;
+		}
 	}
 
+	newsrc = rt->rt_src;
+	DEBUGP("newsrc = %u.%u.%u.%u\n", NIPQUAD(newsrc));
+	ip_rt_put(rt);
+
 	write_lock_bh(&masq_lock);
 	ct->nat.masq_index = out->ifindex;
 	write_unlock_bh(&masq_lock);
diff -urN linux-2.6.19.old/net/ipv4/route.c linux-2.6.19.dev/net/ipv4/route.c
--- linux-2.6.19.old/net/ipv4/route.c	2006-11-29 22:57:37.000000000 +0100
+++ linux-2.6.19.dev/net/ipv4/route.c	2006-12-14 03:13:53.000000000 +0100
@@ -1211,6 +1211,7 @@
 
 				/* Gateway is different ... */
 				rt->rt_gateway		= new_gw;
+				if (rt->fl.fl4_gw) rt->fl.fl4_gw = new_gw;
 
 				/* Redirect received -> path was valid */
 				dst_confirm(&rth->u.dst);
@@ -1647,6 +1648,7 @@
 	rth->fl.fl4_fwmark= skb->nfmark;
 #endif
 	rth->fl.fl4_src	= saddr;
+	rth->fl.fl4_lsrc = 0;
 	rth->rt_src	= saddr;
 #ifdef CONFIG_NET_CLS_ROUTE
 	rth->u.dst.tclassid = itag;
@@ -1657,6 +1659,7 @@
 	dev_hold(rth->u.dst.dev);
 	rth->idev	= in_dev_get(rth->u.dst.dev);
 	rth->fl.oif	= 0;
+	rth->fl.fl4_gw	= 0;
 	rth->rt_gateway	= daddr;
 	rth->rt_spec_dst= spec_dst;
 	rth->rt_type	= RTN_MULTICAST;
@@ -1721,7 +1724,7 @@
 				  struct fib_result* res, 
 				  struct in_device *in_dev, 
 				  __be32 daddr, __be32 saddr, u32 tos,
-				  struct rtable **result) 
+				  u32 lsrc, struct rtable **result) 
 {
 
 	struct rtable *rth;
@@ -1755,6 +1758,7 @@
 		flags |= RTCF_DIRECTSRC;
 
 	if (out_dev == in_dev && err && !(flags & (RTCF_NAT | RTCF_MASQ)) &&
+	    !lsrc &&
 	    (IN_DEV_SHARED_MEDIA(out_dev) ||
 	     inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
 		flags |= RTCF_DOREDIRECT;
@@ -1794,6 +1798,7 @@
 #endif
 	rth->fl.fl4_src	= saddr;
 	rth->rt_src	= saddr;
+	rth->fl.fl4_lsrc	= lsrc;
 	rth->rt_gateway	= daddr;
 	rth->rt_iif 	=
 		rth->fl.iif	= in_dev->dev->ifindex;
@@ -1801,6 +1806,7 @@
 	dev_hold(rth->u.dst.dev);
 	rth->idev	= in_dev_get(rth->u.dst.dev);
 	rth->fl.oif 	= 0;
+	rth->fl.fl4_gw	= 0;
 	rth->rt_spec_dst= spec_dst;
 
 	rth->u.dst.input = ip_forward;
@@ -1822,19 +1828,21 @@
 				       struct fib_result* res, 
 				       const struct flowi *fl,
 				       struct in_device *in_dev,
-				       __be32 daddr, __be32 saddr, u32 tos)
+				       __be32 daddr, __be32 saddr, u32 tos, 
+				       u32 lsrc)
 {
 	struct rtable* rth = NULL;
 	int err;
 	unsigned hash;
 
+	fib_select_default(fl, res);
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
-	if (res->fi && res->fi->fib_nhs > 1 && fl->oif == 0)
+	if (res->fi && res->fi->fib_nhs > 1)
 		fib_select_multipath(fl, res);
 #endif
 
 	/* create a routing cache entry */
-	err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth);
+	err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, lsrc, &rth);
 	if (err)
 		return err;
 
@@ -1847,7 +1855,8 @@
 				   struct fib_result* res, 
 				   const struct flowi *fl,
 				   struct in_device *in_dev,
-				   __be32 daddr, __be32 saddr, u32 tos)
+				   __be32 daddr, __be32 saddr, u32 tos, 
+				   u32 lsrc)
 {
 #ifdef CONFIG_IP_ROUTE_MULTIPATH_CACHED
 	struct rtable* rth = NULL, *rtres;
@@ -1863,7 +1872,7 @@
 	/* distinguish between multipath and singlepath */
 	if (hopcount < 2)
 		return ip_mkroute_input_def(skb, res, fl, in_dev, daddr,
-					    saddr, tos);
+					    saddr, tos, 0);
 	
 	/* add all alternatives to the routing cache */
 	for (hop = 0; hop < hopcount; hop++) {
@@ -1875,7 +1884,7 @@
 
 		/* create a routing cache entry */
 		err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos,
-				      &rth);
+				      0, &rth);
 		if (err)
 			return err;
 
@@ -1895,7 +1904,7 @@
 	skb->dst = &rtres->u.dst;
 	return err;
 #else /* CONFIG_IP_ROUTE_MULTIPATH_CACHED  */
-	return ip_mkroute_input_def(skb, res, fl, in_dev, daddr, saddr, tos);
+	return ip_mkroute_input_def(skb, res, fl, in_dev, daddr, saddr, tos, lsrc);
 #endif /* CONFIG_IP_ROUTE_MULTIPATH_CACHED  */
 }
 
@@ -1911,20 +1920,20 @@
  */
 
 static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
-			       u8 tos, struct net_device *dev)
+			       u8 tos, struct net_device *dev, u32 lsrc)
 {
 	struct fib_result res;
 	struct in_device *in_dev = in_dev_get(dev);
 	struct flowi fl = { .nl_u = { .ip4_u =
 				      { .daddr = daddr,
-					.saddr = saddr,
+					.saddr = lsrc? : saddr,
 					.tos = tos,
 					.scope = RT_SCOPE_UNIVERSE,
 #ifdef CONFIG_IP_ROUTE_FWMARK
 					.fwmark = skb->nfmark
 #endif
 				      } },
-			    .iif = dev->ifindex };
+			    .iif = lsrc? loopback_dev.ifindex : dev->ifindex };
 	unsigned	flags = 0;
 	u32		itag = 0;
 	struct rtable * rth;
@@ -1957,6 +1966,12 @@
 	if (BADCLASS(daddr) || ZERONET(daddr) || LOOPBACK(daddr))
 		goto martian_destination;
 
+	if (lsrc) {
+		if (MULTICAST(lsrc) || BADCLASS(lsrc) ||
+		    ZERONET(lsrc) || LOOPBACK(lsrc))
+			goto e_inval;
+	}
+
 	/*
 	 *	Now we are ready to route packet.
 	 */
@@ -1966,6 +1981,10 @@
 		goto no_route;
 	}
 	free_res = 1;
+	if (lsrc && res.type != RTN_UNICAST && res.type != RTN_NAT)
+		goto e_inval;
+	fl.iif = dev->ifindex;
+	fl.fl4_src = saddr;
 
 	RT_CACHE_STAT_INC(in_slow_tot);
 
@@ -1990,7 +2009,7 @@
 	if (res.type != RTN_UNICAST)
 		goto martian_destination;
 
-	err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos);
+	err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos, lsrc);
 	if (err == -ENOBUFS)
 		goto e_nobufs;
 	if (err == -EINVAL)
@@ -2005,6 +2024,8 @@
 brd_input:
 	if (skb->protocol != htons(ETH_P_IP))
 		goto e_inval;
+	if (lsrc)
+		goto e_inval;
 
 	if (ZERONET(saddr))
 		spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
@@ -2047,6 +2068,7 @@
 	rth->u.dst.dev	= &loopback_dev;
 	dev_hold(rth->u.dst.dev);
 	rth->idev	= in_dev_get(rth->u.dst.dev);
+	rth->fl.fl4_gw	= 0;
 	rth->rt_gateway	= daddr;
 	rth->rt_spec_dst= spec_dst;
 	rth->u.dst.input= ip_local_deliver;
@@ -2096,8 +2118,9 @@
 	goto e_inval;
 }
 
-int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
-		   u8 tos, struct net_device *dev)
+static inline int
+ip_route_input_cached(struct sk_buff *skb, __be32 daddr, __be32 saddr,
+		   u8 tos, struct net_device *dev, u32 lsrc)
 {
 	struct rtable * rth;
 	unsigned	hash;
@@ -2112,6 +2135,7 @@
 		if (rth->fl.fl4_dst == daddr &&
 		    rth->fl.fl4_src == saddr &&
 		    rth->fl.iif == iif &&
+		    rth->fl.fl4_lsrc == lsrc &&
 		    rth->fl.oif == 0 &&
 #ifdef CONFIG_IP_ROUTE_FWMARK
 		    rth->fl.fl4_fwmark == skb->nfmark &&
@@ -2160,7 +2184,19 @@
 		rcu_read_unlock();
 		return -EINVAL;
 	}
-	return ip_route_input_slow(skb, daddr, saddr, tos, dev);
+	return ip_route_input_slow(skb, daddr, saddr, tos, dev, lsrc);
+}
+
+int ip_route_input(struct sk_buff *skb, u32 daddr, u32 saddr,
+		   u8 tos, struct net_device *dev)
+{
+	return ip_route_input_cached(skb, daddr, saddr, tos, dev, 0);
+}
+
+int ip_route_input_lookup(struct sk_buff *skb, u32 daddr, u32 saddr,
+			  u8 tos, struct net_device *dev, u32 lsrc)
+{
+	return ip_route_input_cached(skb, daddr, saddr, tos, dev, lsrc);
 }
 
 static inline int __mkroute_output(struct rtable **result,
@@ -2239,6 +2275,7 @@
 	rth->fl.fl4_tos	= tos;
 	rth->fl.fl4_src	= oldflp->fl4_src;
 	rth->fl.oif	= oldflp->oif;
+	rth->fl.fl4_gw	= oldflp->fl4_gw;
 #ifdef CONFIG_IP_ROUTE_FWMARK
 	rth->fl.fl4_fwmark= oldflp->fl4_fwmark;
 #endif
@@ -2381,6 +2418,7 @@
 	struct flowi fl = { .nl_u = { .ip4_u =
 				      { .daddr = oldflp->fl4_dst,
 					.saddr = oldflp->fl4_src,
+					.gw = oldflp->fl4_gw,
 					.tos = tos & IPTOS_RT_MASK,
 					.scope = ((tos & RTO_ONLINK) ?
 						  RT_SCOPE_LINK :
@@ -2486,6 +2524,7 @@
 		dev_out = &loopback_dev;
 		dev_hold(dev_out);
 		fl.oif = loopback_dev.ifindex;
+		fl.fl4_gw = 0;
 		res.type = RTN_LOCAL;
 		flags |= RTCF_LOCAL;
 		goto make_route;
@@ -2493,7 +2532,7 @@
 
 	if (fib_lookup(&fl, &res)) {
 		res.fi = NULL;
-		if (oldflp->oif) {
+		if (oldflp->oif && dev_out->flags & IFF_UP) {
 			/* Apparently, routing tables are wrong. Assume,
 			   that the destination is on link.
 
@@ -2533,6 +2572,7 @@
 		dev_out = &loopback_dev;
 		dev_hold(dev_out);
 		fl.oif = dev_out->ifindex;
+		fl.fl4_gw = 0;
 		if (res.fi)
 			fib_info_put(res.fi);
 		res.fi = NULL;
@@ -2540,13 +2580,12 @@
 		goto make_route;
 	}
 
+	if (res.type == RTN_UNICAST)
+		fib_select_default(&fl, &res);
 #ifdef CONFIG_IP_ROUTE_MULTIPATH
-	if (res.fi->fib_nhs > 1 && fl.oif == 0)
+	if (res.fi->fib_nhs > 1)
 		fib_select_multipath(&fl, &res);
-	else
 #endif
-	if (!res.prefixlen && res.type == RTN_UNICAST && !fl.oif)
-		fib_select_default(&fl, &res);
 
 	if (!fl.fl4_src)
 		fl.fl4_src = FIB_RES_PREFSRC(res);
@@ -2583,6 +2622,7 @@
 		    rth->fl.fl4_src == flp->fl4_src &&
 		    rth->fl.iif == 0 &&
 		    rth->fl.oif == flp->oif &&
+		    rth->fl.fl4_gw == flp->fl4_gw &&
 #ifdef CONFIG_IP_ROUTE_FWMARK
 		    rth->fl.fl4_fwmark == flp->fl4_fwmark &&
 #endif
@@ -3221,3 +3261,4 @@
 EXPORT_SYMBOL(__ip_select_ident);
 EXPORT_SYMBOL(ip_route_input);
 EXPORT_SYMBOL(ip_route_output_key);
+EXPORT_SYMBOL(ip_route_input_lookup);