[PATCH 3.10 37/54] ipv6: fill rt6i_gateway with nexthop address

Greg Kroah-Hartman
2013-11-01T22:32:26Z

From: Julian Anastasov <ja@ssi.bg>

[ Upstream commit 550bab42f83308c9d6ab04a980cc4333cef1c8fa ]

Make sure rt6i_gateway contains nexthop information in
all routes returned from lookup or when routes are directly
attached to skb for generated ICMP packets.

The effect of this patch should be a faster version of
rt6_nexthop() and the consideration of local addresses as
nexthop.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/net/ip6_route.h | 6 ++----
net/ipv6/ip6_output.c | 4 ++--
net/ipv6/route.c | 8 ++++++--
3 files changed, 10 insertions(+), 8 deletions(-)

--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -194,11 +194,9 @@ static inline int ip6_skb_dst_mtu(struct
skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
}

-static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt, struct in6_addr *dest)
+static inline struct in6_addr *rt6_nexthop(struct rt6_info *rt)
{
- if (rt->rt6i_flags & RTF_GATEWAY || !ipv6_addr_any(&rt->rt6i_gateway))
- return &rt->rt6i_gateway;
- return dest;
+ return &rt->rt6i_gateway;
}

#endif
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -130,7 +130,7 @@ static int ip6_finish_output2(struct sk_
}

rcu_read_lock_bh();
- nexthop = rt6_nexthop((struct rt6_info *)dst, &ipv6_hdr(skb)->daddr);
+ nexthop = rt6_nexthop((struct rt6_info *)dst);
neigh = __ipv6_neigh_lookup_noref(dst->dev, nexthop);
if (unlikely(!neigh))
neigh = __neigh_create(&nd_tbl, nexthop, dst->dev, false);
@@ -898,7 +898,7 @@ static int ip6_dst_lookup_tail(struct so
*/
rt = (struct rt6_info *) *dst;
rcu_read_lock_bh();
- n = __ipv6_neigh_lookup_noref(rt->dst.dev, rt6_nexthop(rt, &fl6->daddr));
+ n = __ipv6_neigh_lookup_noref(rt->dst.dev, rt6_nexthop(rt));
err = n && !(n->nud_state & NUD_VALID) ? -EINVAL : 0;
rcu_read_unlock_bh();

--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -848,7 +848,6 @@ static struct rt6_info *rt6_alloc_cow(st
if (ort->rt6i_dst.plen != 128 &&
ipv6_addr_equal(&ort->rt6i_dst.addr, daddr))
rt->rt6i_flags |= RTF_ANYCAST;
- rt->rt6i_gateway = *daddr;
}

rt->rt6i_flags |= RTF_CACHE;
@@ -1245,6 +1244,7 @@ struct dst_entry *icmp6_dst_alloc(struct
rt->dst.flags |= DST_HOST;
rt->dst.output = ip6_output;
atomic_set(&rt->dst.__refcnt, 1);
+ rt->rt6i_gateway = fl6->daddr;
rt->rt6i_dst.addr = fl6->daddr;
rt->rt6i_dst.plen = 128;
rt->rt6i_idev = idev;
@@ -1801,7 +1801,10 @@ static struct rt6_info *ip6_rt_copy(stru
in6_dev_hold(rt->rt6i_idev);
rt->dst.lastuse = jiffies;

- rt->rt6i_gateway = ort->rt6i_gateway;
+ if (ort->rt6i_flags & RTF_GATEWAY)
+ rt->rt6i_gateway = ort->rt6i_gateway;
+ else
+ rt->rt6i_gateway = *dest;
rt->rt6i_flags = ort->rt6i_flags;
if ((ort->rt6i_flags & (RTF_DEFAULT | RTF_ADDRCONF)) ==
(RTF_DEFAULT | RTF_ADDRCONF))
@@ -2088,6 +2091,7 @@ struct rt6_info *addrconf_dst_alloc(stru
else
rt->rt6i_flags |= RTF_LOCAL;

+ rt->rt6i_gateway = *addr;
rt->rt6i_dst.addr = *addr;
rt->rt6i_dst.plen = 128;
rt->rt6i_table = fib6_get_table(net, RT6_TABLE_LOCAL);