ipv4: Make output route lookup return rtable directly.

Instead of on the stack.

Signed-off-by: David S. Miller <davem@davemloft.net>

36 files changed, 267 insertions, 224 deletions

diff --git a/drivers/infiniband/core/addr.c b/drivers/infiniband/core/addr.c
index 8aba0ba57de5..2d749937a969 100644
--- a/drivers/infiniband/core/addr.c
+++ b/drivers/infiniband/core/addr.c
@@ -193,10 +193,11 @@ static int addr4_resolve(struct sockaddr_in *src_in,
 	fl.nl_u.ip4_u.saddr = src_ip;
 	fl.oif = addr->bound_dev_if;
 
-	ret = ip_route_output_key(&init_net, &rt, &fl);
-	if (ret)
+	rt = ip_route_output_key(&init_net, &fl);
+	if (IS_ERR(rt)) {
+		ret = PTR_ERR(rt);
 		goto out;
-
+	}
 	src_in->sin_family = AF_INET;
 	src_in->sin_addr.s_addr = rt->rt_src;
 
diff --git a/drivers/infiniband/hw/cxgb3/iwch_cm.c b/drivers/infiniband/hw/cxgb3/iwch_cm.c
index e654285aa6ba..e0ccbc53fbcc 100644
--- a/drivers/infiniband/hw/cxgb3/iwch_cm.c
+++ b/drivers/infiniband/hw/cxgb3/iwch_cm.c
@@ -354,7 +354,8 @@ static struct rtable *find_route(struct t3cdev *dev, __be32 local_ip,
 			  }
 	};
 
-	if (ip_route_output_flow(&init_net, &rt, &fl, NULL))
+	rt = ip_route_output_flow(&init_net, &fl, NULL);
+	if (IS_ERR(rt))
 		return NULL;
 	return rt;
 }
diff --git a/drivers/infiniband/hw/cxgb4/cm.c b/drivers/infiniband/hw/cxgb4/cm.c
index 7e0484f18db5..77b0eef2aad9 100644
--- a/drivers/infiniband/hw/cxgb4/cm.c
+++ b/drivers/infiniband/hw/cxgb4/cm.c
@@ -331,7 +331,8 @@ static struct rtable *find_route(struct c4iw_dev *dev, __be32 local_ip,
 			  }
 	};
 
-	if (ip_route_output_flow(&init_net, &rt, &fl, NULL))
+	rt = ip_route_output_flow(&init_net, &fl, NULL);
+	if (IS_ERR(rt))
 		return NULL;
 	return rt;
 }
diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c
index ec3aa11c36cb..e81599cb1fe6 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c
@@ -1112,7 +1112,8 @@ static int nes_addr_resolve_neigh(struct nes_vnic *nesvnic, u32 dst_ip, int arpi
 
 	memset(&fl, 0, sizeof fl);
 	fl.nl_u.ip4_u.daddr = htonl(dst_ip);
-	if (ip_route_output_key(&init_net, &rt, &fl)) {
+	rt = ip_route_output_key(&init_net, &fl);
+	if (IS_ERR(rt)) {
 		printk(KERN_ERR "%s: ip_route_output_key failed for 0x%08X\n",
 				__func__, dst_ip);
 		return rc;
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 584f97b73060..0592e6da15a6 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2681,7 +2681,7 @@ static void bond_arp_send(struct net_device *slave_dev, int arp_op, __be32 dest_
 
 static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
 {
-	int i, vlan_id, rv;
+	int i, vlan_id;
 	__be32 *targets = bond->params.arp_targets;
 	struct vlan_entry *vlan;
 	struct net_device *vlan_dev;
@@ -2708,8 +2708,8 @@ static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
 		fl.fl4_dst = targets[i];
 		fl.fl4_tos = RTO_ONLINK;
 
-		rv = ip_route_output_key(dev_net(bond->dev), &rt, &fl);
-		if (rv) {
+		rt = ip_route_output_key(dev_net(bond->dev), &fl);
+		if (IS_ERR(rt)) {
 			if (net_ratelimit()) {
 				pr_warning("%s: no route to arp_ip_target %pI4\n",
 					   bond->dev->name, &fl.fl4_dst);
diff --git a/drivers/net/cnic.c b/drivers/net/cnic.c
index 5274de3e1bb9..25f08880ae0f 100644
--- a/drivers/net/cnic.c
+++ b/drivers/net/cnic.c
@@ -3397,9 +3397,12 @@ static int cnic_get_v4_route(struct sockaddr_in *dst_addr,
 	memset(&fl, 0, sizeof(fl));
 	fl.nl_u.ip4_u.daddr = dst_addr->sin_addr.s_addr;
 
-	err = ip_route_output_key(&init_net, &rt, &fl);
-	if (!err)
+	rt = ip_route_output_key(&init_net, &fl);
+	err = 0;
+	if (!IS_ERR(rt))
 		*dst = &rt->dst;
+	else
+		err = PTR_ERR(rt);
 	return err;
 #else
 	return -ENETUNREACH;
diff --git a/drivers/net/pptp.c b/drivers/net/pptp.c
index 164cfad6ce79..1af549c89d51 100644
--- a/drivers/net/pptp.c
+++ b/drivers/net/pptp.c
@@ -175,7 +175,6 @@ static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
 	struct pptp_opt *opt = &po->proto.pptp;
 	struct pptp_gre_header *hdr;
 	unsigned int header_len = sizeof(*hdr);
-	int err = 0;
 	int islcp;
 	int len;
 	unsigned char *data;
@@ -198,8 +197,8 @@ static int pptp_xmit(struct ppp_channel *chan, struct sk_buff *skb)
 					.saddr = opt->src_addr.sin_addr.s_addr,
 					.tos = RT_TOS(0) } },
 			.proto = IPPROTO_GRE };
-		err = ip_route_output_key(&init_net, &rt, &fl);
-		if (err)
+		rt = ip_route_output_key(&init_net, &fl);
+		if (IS_ERR(rt))
 			goto tx_error;
 	}
 	tdev = rt->dst.dev;
@@ -477,7 +476,8 @@ static int pptp_connect(struct socket *sock, struct sockaddr *uservaddr,
 					.tos = RT_CONN_FLAGS(sk) } },
 			.proto = IPPROTO_GRE };
 		security_sk_classify_flow(sk, &fl);
-		if (ip_route_output_key(&init_net, &rt, &fl)) {
+		rt = ip_route_output_key(&init_net, &fl);
+		if (IS_ERR(rt)) {
 			error = -EHOSTUNREACH;
 			goto end;
 		}
diff --git a/drivers/scsi/cxgbi/libcxgbi.c b/drivers/scsi/cxgbi/libcxgbi.c
index 261aa817bdd5..889199aa1f5b 100644
--- a/drivers/scsi/cxgbi/libcxgbi.c
+++ b/drivers/scsi/cxgbi/libcxgbi.c
@@ -470,7 +470,8 @@ static struct rtable *find_route_ipv4(__be32 saddr, __be32 daddr,
 			}
 	};
 
-	if (ip_route_output_flow(&init_net, &rt, &fl, NULL))
+	rt = ip_route_output_flow(&init_net, &fl, NULL);
+	if (IS_ERR(rt))
 		return NULL;
 
 	return rt;
diff --git a/include/net/route.h b/include/net/route.h
index 707cfc8eccdc..088a1867348f 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -118,9 +118,10 @@ extern void		ip_rt_redirect(__be32 old_gw, __be32 dst, __be32 new_gw,
 				       __be32 src, struct net_device *dev);
 extern void		rt_cache_flush(struct net *net, int how);
 extern void		rt_cache_flush_batch(struct net *net);
-extern int		__ip_route_output_key(struct net *, struct rtable **, const struct flowi *flp);
-extern int		ip_route_output_key(struct net *, struct rtable **, struct flowi *flp);
-extern int		ip_route_output_flow(struct net *, struct rtable **rp, struct flowi *flp, struct sock *sk);
+extern struct rtable *__ip_route_output_key(struct net *, const struct flowi *flp);
+extern struct rtable *ip_route_output_key(struct net *, struct flowi *flp);
+extern struct rtable *ip_route_output_flow(struct net *, struct flowi *flp,
+					   struct sock *sk);
 extern struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig);
 
 extern int ip_route_input_common(struct sk_buff *skb, __be32 dst, __be32 src,
@@ -166,10 +167,10 @@ static inline char rt_tos2priority(u8 tos)
 	return ip_tos2prio[IPTOS_TOS(tos)>>1];
 }
 
-static inline int ip_route_connect(struct rtable **rp, __be32 dst,
-				   __be32 src, u32 tos, int oif, u8 protocol,
-				   __be16 sport, __be16 dport, struct sock *sk,
-				   bool can_sleep)
+static inline struct rtable *ip_route_connect(__be32 dst, __be32 src, u32 tos,
+					      int oif, u8 protocol,
+					      __be16 sport, __be16 dport,
+					      struct sock *sk, bool can_sleep)
 {
 	struct flowi fl = { .oif = oif,
 			    .mark = sk->sk_mark,
@@ -179,8 +180,8 @@ static inline int ip_route_connect(struct rtable **rp, __be32 dst,
 			    .proto = protocol,
 			    .fl_ip_sport = sport,
 			    .fl_ip_dport = dport };
-	int err;
 	struct net *net = sock_net(sk);
+	struct rtable *rt;
 
 	if (inet_sk(sk)->transparent)
 		fl.flags |= FLOWI_FLAG_ANYSRC;
@@ -190,29 +191,29 @@ static inline int ip_route_connect(struct rtable **rp, __be32 dst,
 		fl.flags |= FLOWI_FLAG_CAN_SLEEP;
 
 	if (!dst || !src) {
-		err = __ip_route_output_key(net, rp, &fl);
-		if (err)
-			return err;
-		fl.fl4_dst = (*rp)->rt_dst;
-		fl.fl4_src = (*rp)->rt_src;
-		ip_rt_put(*rp);
-		*rp = NULL;
+		rt = __ip_route_output_key(net, &fl);
+		if (IS_ERR(rt))
+			return rt;
+		fl.fl4_dst = rt->rt_dst;
+		fl.fl4_src = rt->rt_src;
+		ip_rt_put(rt);
 	}
 	security_sk_classify_flow(sk, &fl);
-	return ip_route_output_flow(net, rp, &fl, sk);
+	return ip_route_output_flow(net, &fl, sk);
 }
 
-static inline int ip_route_newports(struct rtable **rp, u8 protocol,
-				    __be16 orig_sport, __be16 orig_dport,
-				    __be16 sport, __be16 dport, struct sock *sk)
+static inline struct rtable *ip_route_newports(struct rtable *rt,
+					       u8 protocol, __be16 orig_sport,
+					       __be16 orig_dport, __be16 sport,
+					       __be16 dport, struct sock *sk)
 {
 	if (sport != orig_sport || dport != orig_dport) {
-		struct flowi fl = { .oif = (*rp)->fl.oif,
-				    .mark = (*rp)->fl.mark,
-				    .fl4_dst = (*rp)->fl.fl4_dst,
-				    .fl4_src = (*rp)->fl.fl4_src,
-				    .fl4_tos = (*rp)->fl.fl4_tos,
-				    .proto = (*rp)->fl.proto,
+		struct flowi fl = { .oif = rt->fl.oif,
+				    .mark = rt->fl.mark,
+				    .fl4_dst = rt->fl.fl4_dst,
+				    .fl4_src = rt->fl.fl4_src,
+				    .fl4_tos = rt->fl.fl4_tos,
+				    .proto = rt->fl.proto,
 				    .fl_ip_sport = sport,
 				    .fl_ip_dport = dport };
 
@@ -220,12 +221,11 @@ static inline int ip_route_newports(struct rtable **rp, u8 protocol,
 			fl.flags |= FLOWI_FLAG_ANYSRC;
 		if (protocol == IPPROTO_TCP)
 			fl.flags |= FLOWI_FLAG_PRECOW_METRICS;
-		ip_rt_put(*rp);
-		*rp = NULL;
+		ip_rt_put(rt);
 		security_sk_classify_flow(sk, &fl);
-		return ip_route_output_flow(sock_net(sk), rp, &fl, sk);
+		return ip_route_output_flow(sock_net(sk), &fl, sk);
 	}
-	return 0;
+	return rt;
 }
 
 extern void rt_bind_peer(struct rtable *rt, int create);
diff --git a/net/atm/clip.c b/net/atm/clip.c
index d257da50fcfb..810a1294eddb 100644
--- a/net/atm/clip.c
+++ b/net/atm/clip.c
@@ -520,9 +520,9 @@ static int clip_setentry(struct atm_vcc *vcc, __be32 ip)
 		unlink_clip_vcc(clip_vcc);
 		return 0;
 	}
-	error = ip_route_output_key(&init_net, &rt, &fl);
-	if (error)
-		return error;
+	rt = ip_route_output_key(&init_net, &fl);
+	if (IS_ERR(rt))
+		return PTR_ERR(rt);
 	neigh = __neigh_lookup(&clip_tbl, &ip, rt->dst.dev, 1);
 	ip_rt_put(rt);
 	if (!neigh)
diff --git a/net/bridge/br_netfilter.c b/net/bridge/br_netfilter.c
index 4b5b66d07bba..45b57b173f70 100644
--- a/net/bridge/br_netfilter.c
+++ b/net/bridge/br_netfilter.c
@@ -428,14 +428,15 @@ static int br_nf_pre_routing_finish(struct sk_buff *skb)
 			if (err != -EHOSTUNREACH || !in_dev || IN_DEV_FORWARD(in_dev))
 				goto free_skb;
 
-			if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
+			rt = ip_route_output_key(dev_net(dev), &fl);
+			if (!IS_ERR(rt)) {
 				/* - Bridged-and-DNAT'ed traffic doesn't
 				 *   require ip_forwarding. */
-				if (((struct dst_entry *)rt)->dev == dev) {
-					skb_dst_set(skb, (struct dst_entry *)rt);
+				if (rt->dst.dev == dev) {
+					skb_dst_set(skb, &rt->dst);
 					goto bridged_dnat;
 				}
-				dst_release((struct dst_entry *)rt);
+				ip_rt_put(rt);
 			}
 free_skb:
 			kfree_skb(skb);
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index a8ff95502081..7882377bc62e 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -46,7 +46,6 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	__be16 orig_sport, orig_dport;
 	struct rtable *rt;
 	__be32 daddr, nexthop;
-	int tmp;
 	int err;
 
 	dp->dccps_role = DCCP_ROLE_CLIENT;
@@ -66,12 +65,12 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 
 	orig_sport = inet->inet_sport;
 	orig_dport = usin->sin_port;
-	tmp = ip_route_connect(&rt, nexthop, inet->inet_saddr,
-			       RT_CONN_FLAGS(sk), sk->sk_bound_dev_if,
-			       IPPROTO_DCCP,
-			       orig_sport, orig_dport, sk, true);
-	if (tmp < 0)
-		return tmp;
+	rt = ip_route_connect(nexthop, inet->inet_saddr,
+			      RT_CONN_FLAGS(sk), sk->sk_bound_dev_if,
+			      IPPROTO_DCCP,
+			      orig_sport, orig_dport, sk, true);
+	if (IS_ERR(rt))
+		return PTR_ERR(rt);
 
 	if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) {
 		ip_rt_put(rt);
@@ -102,12 +101,13 @@ int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 	if (err != 0)
 		goto failure;
 
-	err = ip_route_newports(&rt, IPPROTO_DCCP,
-				orig_sport, orig_dport,
-				inet->inet_sport, inet->inet_dport, sk);
-	if (err != 0)
+	rt = ip_route_newports(rt, IPPROTO_DCCP,
+			       orig_sport, orig_dport,
+			       inet->inet_sport, inet->inet_dport, sk);
+	if (IS_ERR(rt)) {
+		rt = NULL;
 		goto failure;
-
+	}
 	/* OK, now commit destination to socket.  */
 	sk_setup_caps(sk, &rt->dst);
 
@@ -475,7 +475,8 @@ static struct dst_entry* dccp_v4_route_skb(struct net *net, struct sock *sk,
 			  };
 
 	security_skb_classify_flow(skb, &fl);
-	if (ip_route_output_flow(net, &rt, &fl, sk)) {
+	rt = ip_route_output_flow(net, &fl, sk);
+	if (IS_ERR(rt)) {
 		IP_INC_STATS_BH(net, IPSTATS_MIB_OUTNOROUTES);
 		return NULL;
 	}
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 44513bb8ac2e..35a502055018 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1101,23 +1101,20 @@ int sysctl_ip_dynaddr __read_mostly;
 static int inet_sk_reselect_saddr(struct sock *sk)
 {
 	struct inet_sock *inet = inet_sk(sk);
-	int err;
-	struct rtable *rt;
 	__be32 old_saddr = inet->inet_saddr;
-	__be32 new_saddr;
 	__be32 daddr = inet->inet_daddr;
+	struct rtable *rt;
+	__be32 new_saddr;
 
 	if (inet->opt && inet->opt->srr)
 		daddr = inet->opt->faddr;
 
 	/* Query new route. */
-	err = ip_route_connect(&rt, daddr, 0,
-			       RT_CONN_FLAGS(sk),
-			       sk->sk_bound_dev_if,
-			       sk->sk_protocol,
-			       inet->inet_sport, inet->inet_dport, sk, false);
-	if (err)
-		return err;
+	rt = ip_route_connect(daddr, 0, RT_CONN_FLAGS(sk),
+			      sk->sk_bound_dev_if, sk->sk_protocol,
+			      inet->inet_sport, inet->inet_dport, sk, false);
+	if (IS_ERR(rt))
+		return PTR_ERR(rt);
 
 	sk_setup_caps(sk, &rt->dst);
 
@@ -1160,7 +1157,7 @@ int inet_sk_rebuild_header(struct sock *sk)
 	daddr = inet->inet_daddr;
 	if (inet->opt && inet->opt->srr)
 		daddr = inet->opt->faddr;
-{
+	{
 	struct flowi fl = {
 		.oif = sk->sk_bound_dev_if,
 		.mark = sk->sk_mark,
@@ -1174,11 +1171,14 @@ int inet_sk_rebuild_header(struct sock *sk)
 	};
 
 	security_sk_classify_flow(sk, &fl);
-	err = ip_route_output_flow(sock_net(sk), &rt, &fl, sk);
-}
-	if (!err)
+	rt = ip_route_output_flow(sock_net(sk), &fl, sk);
+	}
+	if (!IS_ERR(rt)) {
+		err = 0;
 		sk_setup_caps(sk, &rt->dst);
-	else {
+	} else {
+		err = PTR_ERR(rt);
+
 		/* Routing failed... */
 		sk->sk_route_caps = 0;
 		/*
diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index 7927589813b5..fa9988da1da4 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -440,7 +440,8 @@ static int arp_filter(__be32 sip, __be32 tip, struct net_device *dev)
 	/*unsigned long now; */
 	struct net *net = dev_net(dev);
 
-	if (ip_route_output_key(net, &rt, &fl) < 0)
+	rt = ip_route_output_key(net, &fl);
+	if (IS_ERR(rt))
 		return 1;
 	if (rt->dst.dev != dev) {
 		NET_INC_STATS_BH(net, LINUX_MIB_ARPFILTER);
@@ -1063,10 +1064,10 @@ static int arp_req_set(struct net *net, struct arpreq *r,
 	if (dev == NULL) {
 		struct flowi fl = { .fl4_dst = ip,
 				    .fl4_tos = RTO_ONLINK };
-		struct rtable *rt;
-		err = ip_route_output_key(net, &rt, &fl);
-		if (err != 0)
-			return err;
+		struct rtable *rt = ip_route_output_key(net, &fl);
+
+		if (IS_ERR(rt))
+			return PTR_ERR(rt);
 		dev = rt->dst.dev;
 		ip_rt_put(rt);
 		if (!dev)
@@ -1177,7 +1178,6 @@ static int arp_req_delete_public(struct net *net, struct arpreq *r,
 static int arp_req_delete(struct net *net, struct arpreq *r,
 			  struct net_device *dev)
 {
-	int err;
 	__be32 ip;
 
 	if (r->arp_flags & ATF_PUBL)
@@ -1187,10 +1187,9 @@ static int arp_req_delete(struct net *net, struct arpreq *r,
 	if (dev == NULL) {
 		struct flowi fl = { .fl4_dst = ip,
 				    .fl4_tos = RTO_ONLINK };
-		struct rtable *rt;
-		err = ip_route_output_key(net, &rt, &fl);
-		if (err != 0)
-			return err;
+		struct rtable *rt = ip_route_output_key(net, &fl);
+		if (IS_ERR(rt))
+			return PTR_ERR(rt);
 		dev = rt->dst.dev;
 		ip_rt_put(rt);
 		if (!dev)
diff --git a/net/ipv4/datagram.c b/net/ipv4/datagram.c
index eaee1edd2dd7..85bd24ca4f6d 100644
--- a/net/ipv4/datagram.c
+++ b/net/ipv4/datagram.c
@@ -46,11 +46,12 @@ int ip4_datagram_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
 		if (!saddr)
 			saddr = inet->mc_addr;
 	}
-	err = ip_route_connect(&rt, usin->sin_addr.s_addr, saddr,
-			       RT_CONN_FLAGS(sk), oif,
-			       sk->sk_protocol,
-			       inet->inet_sport, usin->sin_port, sk, true);
-	if (err) {
+	rt = ip_route_connect(usin->sin_addr.s_addr, saddr,
+			      RT_CONN_FLAGS(sk), oif,
+			      sk->sk_protocol,
+			      inet->inet_sport, usin->sin_port, sk, true);
+	if (IS_ERR(rt)) {
+		err = PTR_ERR(rt);
 		if (err == -ENETUNREACH)
 			IP_INC_STATS_BH(sock_net(sk), IPSTATS_MIB_OUTNOROUTES);
 		return err;
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index c23bd8cdeee0..994a785d98f9 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -358,7 +358,8 @@ static void icmp_reply(struct icmp_bxm *icmp_param, struct sk_buff *skb)
 				    .fl4_tos = RT_TOS(ip_hdr(skb)->tos),
 				    .proto = IPPROTO_ICMP };
 		security_skb_classify_flow(skb, &fl);
-		if (ip_route_output_key(net, &rt, &fl))
+		rt = ip_route_output_key(net, &fl);
+		if (IS_ERR(rt))
 			goto out_unlock;
 	}
 	if (icmpv4_xrlim_allow(net, rt, icmp_param->data.icmph.type,
@@ -388,9 +389,9 @@ static struct rtable *icmp_route_lookup(struct net *net, struct sk_buff *skb_in,
 	int err;
 
 	security_skb_classify_flow(skb_in, &fl);
-	err = __ip_route_output_key(net, &rt, &fl);
-	if (err)
-		return ERR_PTR(err);
+	rt = __ip_route_output_key(net, &fl);
+	if (IS_ERR(rt))
+		return rt;
 
 	/* No need to clone since we're just using its address. */
 	rt2 = rt;
@@ -412,15 +413,19 @@ static struct rtable *icmp_route_lookup(struct net *net, struct sk_buff *skb_in,
 		goto relookup_failed;
 
 	if (inet_addr_type(net, fl.fl4_src) == RTN_LOCAL) {
-		err = __ip_route_output_key(net, &rt2, &fl);
+		rt2 = __ip_route_output_key(net, &fl);
+		if (IS_ERR(rt2))
+			err = PTR_ERR(rt2);
 	} else {
 		struct flowi fl2 = {};
 		unsigned long orefdst;
 
 		fl2.fl4_dst = fl.fl4_src;
-		err = ip_route_output_key(net, &rt2, &fl2);
-		if (err)
+		rt2 = ip_route_output_key(net, &fl2);
+		if (IS_ERR(rt2)) {
+			err = PTR_ERR(rt2);
 			goto relookup_failed;
+		}
 		/* Ugh! */
 		orefdst = skb_in->_skb_refdst; /* save old refdst */
 		err = ip_route_input(skb_in, fl.fl4_dst, fl.fl4_src,
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index e0e77e297de3..44ba9068b72f 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -325,7 +325,8 @@ static struct sk_buff *igmpv3_newpack(struct net_device *dev, int size)
 		struct flowi fl = { .oif = dev->ifindex,
 				    .fl4_dst = IGMPV3_ALL_MCR,
 				    .proto = IPPROTO_IGMP };
-		if (ip_route_output_key(net, &rt, &fl)) {
+		rt = ip_route_output_key(net, &fl);
+		if (IS_ERR(rt)) {
 			kfree_skb(skb);
 			return NULL;
 		}
@@ -670,7 +671,8 @@ static int igmp_send_report(struct in_device *in_dev, struct ip_mc_list *pmc,
 		struct flowi fl = { .oif = dev->ifindex,
 				    .fl4_dst = dst,
 				    .proto = IPPROTO_IGMP };
-		if (ip_route_output_key(net, &rt, &fl))
+		rt = ip_route_output_key(net, &fl);
+		if (IS_ERR(rt))
 			return -1;
 	}
 	if (rt->rt_src == 0) {
@@ -1440,7 +1442,6 @@ void ip_mc_destroy_dev(struct in_device *in_dev)
 static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
 {
 	struct flowi fl = { .fl4_dst = imr->imr_multiaddr.s_addr };
-	struct rtable *rt;
 	struct net_device *dev = NULL;
 	struct in_device *idev = NULL;
 
@@ -1454,9 +1455,12 @@ static struct in_device *ip_mc_find_dev(struct net *net, struct ip_mreqn *imr)
 			return NULL;
 	}
 
-	if (!dev && !ip_route_output_key(net, &rt, &fl)) {
-		dev = rt->dst.dev;
-		ip_rt_put(rt);
+	if (!dev) {
+		struct rtable *rt = ip_route_output_key(net, &fl);
+		if (!IS_ERR(rt)) {
+			dev = rt->dst.dev;
+			ip_rt_put(rt);
+		}
 	}
 	if (dev) {
 		imr->imr_ifindex = dev->ifindex;
diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c
index 7f85d4aec26a..e4e301a61c5b 100644
--- a/net/ipv4/inet_connection_sock.c
+++ b/net/ipv4/inet_connection_sock.c
@@ -369,7 +369,8 @@ struct dst_entry *inet_csk_route_req(struct sock *sk,
 	struct net *net = sock_net(sk);
 
 	security_req_classify_flow(req, &fl);
-	if (ip_route_output_flow(net, &rt, &fl, sk))
+	rt = ip_route_output_flow(net, &fl, sk);
+	if (IS_ERR(rt))
 		goto no_route;
 	if (opt && opt->is_strictroute && rt->rt_dst != rt->rt_gateway)
 		goto route_err;
diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 6613edfac28c..f9af98dd7561 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -778,7 +778,8 @@ static netdev_tx_t ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev
 			.proto = IPPROTO_GRE,
 			.fl_gre_key = tunnel->parms.o_key
 		};
-		if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
+		rt = ip_route_output_key(dev_net(dev), &fl);
+		if (IS_ERR(rt)) {
 			dev->stats.tx_carrier_errors++;
 			goto tx_error;
 		}
@@ -953,9 +954,9 @@ static int ipgre_tunnel_bind_dev(struct net_device *dev)
 			.proto = IPPROTO_GRE,
 			.fl_gre_key = tunnel->parms.o_key
 		};
-		struct rtable *rt;
+		struct rtable *rt = ip_route_output_key(dev_net(dev), &fl);
 
-		if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
+		if (!IS_ERR(rt)) {
 			tdev = rt->dst.dev;
 			ip_rt_put(rt);
 		}
@@ -1215,9 +1216,9 @@ static int ipgre_open(struct net_device *dev)
 			.proto = IPPROTO_GRE,
 			.fl_gre_key = t->parms.o_key
 		};
-		struct rtable *rt;
+		struct rtable *rt = ip_route_output_key(dev_net(dev), &fl);
 
-		if (ip_route_output_key(dev_net(dev), &rt, &fl))
+		if (IS_ERR(rt))
 			return -EADDRNOTAVAIL;
 		dev = rt->dst.dev;
 		ip_rt_put(rt);
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 33316b3534ca..171f483b21d5 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -355,7 +355,8 @@ int ip_queue_xmit(struct sk_buff *skb)
 			 * itself out.
 			 */
 			security_sk_classify_flow(sk, &fl);
-			if (ip_route_output_flow(sock_net(sk), &rt, &fl, sk))
+			rt = ip_route_output_flow(sock_net(sk), &fl, sk);
+			if (IS_ERR(rt))
 				goto no_route;
 		}
 		sk_setup_caps(sk, &rt->dst);
@@ -1489,7 +1490,8 @@ void ip_send_reply(struct sock *sk, struct sk_buff *skb, struct ip_reply_arg *ar
 				    .proto = sk->sk_protocol,
 				    .flags = ip_reply_arg_flowi_flags(arg) };
 		security_skb_classify_flow(skb, &fl);
-		if (ip_route_output_key(sock_net(sk), &rt, &fl))
+		rt = ip_route_output_key(sock_net(sk), &fl);
+		if (IS_ERR(rt))
 			return;
 	}
 
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 988f52fba54a..e1e17576baa6 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -469,7 +469,8 @@ static netdev_tx_t ipip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
 			.proto = IPPROTO_IPIP
 		};
 
-		if (ip_route_output_key(dev_net(dev), &rt, &fl)) {
+		rt = ip_route_output_key(dev_net(dev), &fl);
+		if (IS_ERR(rt)) {
 			dev->stats.tx_carrier_errors++;
 			goto tx_error_icmp;
 		}
@@ -590,9 +591,9 @@ static void ipip_tunnel_bind_dev(struct net_device *dev)
 			.fl4_tos = RT_TOS(iph->tos),
 			.proto = IPPROTO_IPIP
 		};
-		struct rtable *rt;
+		struct rtable *rt = ip_route_output_key(dev_net(dev), &fl);
 
-		if (!ip_route_output_key(dev_net(dev), &rt, &fl)) {
+		if (!IS_ERR(rt)) {
 			tdev = rt->dst.dev;
 			ip_rt_put(rt);
 		}
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 8b65a12654e7..26ca2f2d37ce 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -1618,8 +1618,8 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
 			.fl4_tos = RT_TOS(iph->tos),
 			.proto = IPPROTO_IPIP
 		};
-
-		if (ip_route_output_key(net, &rt, &fl))
+		rt = ip_route_output_key(net, &fl);
+		if (IS_ERR(rt))
 			goto out_free;
 		encap = sizeof(struct iphdr);
 	} else {
@@ -1629,8 +1629,8 @@ static void ipmr_queue_xmit(struct net *net, struct mr_table *mrt,
 			.fl4_tos = RT_TOS(iph->tos),
 			.proto = IPPROTO_IPIP
 		};
-
-		if (ip_route_output_key(net, &rt, &fl))
+		rt = ip_route_output_key(net, &fl);
+		if (IS_ERR(rt))
 			goto out_free;
 	}
 
diff --git a/net/ipv4/