soreuseport: pass skb to secondary UDP socket lookup

This socket-lookup path did not pass along the skb in question
in my original BPF-based socket selection patch.  The skb in the
udpN_lib_lookup2 path can be used for BPF-based socket selection just
like it is in the 'traditional' udpN_lib_lookup path.

udpN_lib_lookup2 kicks in when there are greater than 10 sockets in
the same hlist slot.  Coincidentally, I chose 10 sockets per
reuseport group in my functional test, so the lookup2 path was not
excersised. This adds an additional set of tests with 20 sockets.

Fixes: 538950a1b752 ("soreuseport: setsockopt SO_ATTACH_REUSEPORT_[CE]BPF")
Fixes: 3ca8e4029969 ("soreuseport: BPF selection functional test")
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Craig Gallek <kraig@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 4 deletions

diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 56fcb55fda31..5d2c2afffe7b 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -251,7 +251,8 @@ static inline int compute_score2(struct sock *sk, struct net *net,
 static struct sock *udp6_lib_lookup2(struct net *net,
                 const struct in6_addr *saddr, __be16 sport,
                 const struct in6_addr *daddr, unsigned int hnum, int dif,
-                struct udp_hslot *hslot2, unsigned int slot2)
+                struct udp_hslot *hslot2, unsigned int slot2,
+                struct sk_buff *skb)
 {
         struct sock *sk, *result;
         struct hlist_nulls_node *node;
@@ -272,7 +273,8 @@ begin:
                                 struct sock *sk2;
                                 hash = udp6_ehashfn(net, daddr, hnum,
                                                     saddr, sport);
-                                sk2 = reuseport_select_sock(sk, hash, NULL, 0);
+                                sk2 = reuseport_select_sock(sk, hash, skb,
+                                                            sizeof(struct udphdr));
                                 if (sk2) {
                                         result = sk2;
                                         goto found;
@@ -331,7 +333,7 @@ struct sock *__udp6_lib_lookup(struct net *net,
 
                 result = udp6_lib_lookup2(net, saddr, sport,
                                           daddr, hnum, dif,
-                                          hslot2, slot2);
+                                          hslot2, slot2, skb);
                 if (!result) {
                         hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
                         slot2 = hash2 & udptable->mask;
@@ -341,7 +343,7 @@ struct sock *__udp6_lib_lookup(struct net *net,
 
                         result = udp6_lib_lookup2(net, saddr, sport,
                                                   &in6addr_any, hnum, dif,
-                                                  hslot2, slot2);
+                                                  hslot2, slot2, skb);
                 }
                 rcu_read_unlock();
                 return result;