udp6: set rx_dst_cookie on rx_dst updates

Currently, in the udp6 code, the dst cookie is not initialized/updated
concurrently with the RX dst used by early demux.

As a result, the dst_check() in the early_demux path always fails,
the rx dst cache is always invalidated, and we can't really
leverage significant gain from the demux lookup.

Fix it adding udp6 specific variant of sk_rx_dst_set() and use it
to set the dst cookie when the dst entry is really changed.

The issue is there since the introduction of early demux for ipv6.

Fixes: 5425077d73 ("net: ipv6: Add early demux handler for UDP unicast")
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Paolo Abeni
2017-08-25 14:31:01 +02:00
committed by David S. Miller
parent 2207d182c1
commit 64f0f5d18a
3 changed files with 14 additions and 3 deletions

View File

@@ -768,6 +768,15 @@ start_lookup:
return 0;
}
static void udp6_sk_rx_dst_set(struct sock *sk, struct dst_entry *dst)
{
if (udp_sk_rx_dst_set(sk, dst)) {
const struct rt6_info *rt = (const struct rt6_info *)dst;
inet6_sk(sk)->rx_dst_cookie = rt6_get_cookie(rt);
}
}
int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
int proto)
{
@@ -817,7 +826,7 @@ int __udp6_lib_rcv(struct sk_buff *skb, struct udp_table *udptable,
int ret;
if (unlikely(sk->sk_rx_dst != dst))
udp_sk_rx_dst_set(sk, dst);
udp6_sk_rx_dst_set(sk, dst);
ret = udpv6_queue_rcv_skb(sk, skb);
sock_put(sk);