net: skb->dst accessors

Define three accessors to get/set dst attached to a skb

struct dst_entry *skb_dst(const struct sk_buff *skb)

void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)

void skb_dst_drop(struct sk_buff *skb)
This one should replace occurrences of :
dst_release(skb->dst)
skb->dst = NULL;

Delete skb->dst field

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/udp.c

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 8905712..fc333d8 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -177,10 +177,9 @@
 
 	if (unlikely(sk = skb_steal_sock(skb)))
 		return sk;
-	else
-		return __udp6_lib_lookup(dev_net(skb->dst->dev), &iph->saddr, sport,
-					 &iph->daddr, dport, inet6_iif(skb),
-					 udptable);
+	return __udp6_lib_lookup(dev_net(skb_dst(skb)->dev), &iph->saddr, sport,
+				 &iph->daddr, dport, inet6_iif(skb),
+				 udptable);
 }
 
 /*