1 files changed, 11 insertions, 17 deletions

diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 62c3ed0b75568b..f2be689a6c85b6 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1252,7 +1252,9 @@ static unsigned int ipv4_mtu(const struct dst_entry *dst)
 			mtu = 576;
 	}
 
-	return min_t(unsigned int, mtu, IP_MAX_MTU);
+	mtu = min_t(unsigned int, mtu, IP_MAX_MTU);
+
+	return mtu - lwtunnel_headroom(dst->lwtstate, mtu);
 }
 
 static struct fib_nh_exception *find_exception(struct fib_nh *nh, __be32 daddr)
@@ -1835,7 +1837,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
 	 *	Now we are ready to route packet.
 	 */
 	fl4.flowi4_oif = 0;
-	fl4.flowi4_iif = l3mdev_fib_oif_rcu(dev);
+	fl4.flowi4_iif = dev->ifindex;
 	fl4.flowi4_mark = skb->mark;
 	fl4.flowi4_tos = tos;
 	fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
@@ -2022,7 +2024,9 @@ static struct rtable *__mkroute_output(const struct fib_result *res,
 		return ERR_PTR(-EINVAL);
 
 	if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev)))
-		if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK))
+		if (ipv4_is_loopback(fl4->saddr) &&
+		    !(dev_out->flags & IFF_LOOPBACK) &&
+		    !netif_is_l3_master(dev_out))
 			return ERR_PTR(-EINVAL);
 
 	if (ipv4_is_lbcast(fl4->daddr))
@@ -2152,7 +2156,6 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 	unsigned int flags = 0;
 	struct fib_result res;
 	struct rtable *rth;
-	int master_idx;
 	int orig_oif;
 	int err = -ENETUNREACH;
 
@@ -2162,9 +2165,6 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 
 	orig_oif = fl4->flowi4_oif;
 
-	master_idx = l3mdev_master_ifindex_by_index(net, fl4->flowi4_oif);
-	if (master_idx)
-		fl4->flowi4_oif = master_idx;
 	fl4->flowi4_iif = LOOPBACK_IFINDEX;
 	fl4->flowi4_tos = tos & IPTOS_RT_MASK;
 	fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
@@ -2248,10 +2248,6 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 				fl4->saddr = inet_select_addr(dev_out, 0,
 							      RT_SCOPE_HOST);
 		}
-
-		rth = l3mdev_get_rtable(dev_out, fl4);
-		if (rth)
-			goto out;
 	}
 
 	if (!fl4->daddr) {
@@ -2269,8 +2265,7 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 	if (err) {
 		res.fi = NULL;
 		res.table = NULL;
-		if (fl4->flowi4_oif &&
-		    !netif_index_is_l3_master(net, fl4->flowi4_oif)) {
+		if (fl4->flowi4_oif) {
 			/* Apparently, routing tables are wrong. Assume,
 			   that the destination is on link.
 
@@ -2306,7 +2301,9 @@ struct rtable *__ip_route_output_key_hash(struct net *net, struct flowi4 *fl4,
 			else
 				fl4->saddr = fl4->daddr;
 		}
-		dev_out = net->loopback_dev;
+
+		/* L3 master device is the loopback for that domain */
+		dev_out = l3mdev_master_dev_rcu(dev_out) ? : net->loopback_dev;
 		fl4->flowi4_oif = dev_out->ifindex;
 		flags |= RTCF_LOCAL;
 		goto make_route;
@@ -2582,9 +2579,6 @@ static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr *nlh)
 	fl4.flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0;
 	fl4.flowi4_mark = mark;
 
-	if (netif_index_is_l3_master(net, fl4.flowi4_oif))
-		fl4.flowi4_flags = FLOWI_FLAG_L3MDEV_SRC | FLOWI_FLAG_SKIP_NH_OIF;
-
 	if (iif) {
 		struct net_device *dev;