aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--net/ipv6/udp.c112
1 files changed, 109 insertions, 3 deletions
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index 1e5fadd997b..f580cf92511 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -146,6 +146,88 @@ static inline int compute_score(struct sock *sk, struct net *net,
return score;
}
+#define SCORE2_MAX (1 + 1 + 1)
+static inline int compute_score2(struct sock *sk, struct net *net,
+ const struct in6_addr *saddr, __be16 sport,
+ const struct in6_addr *daddr, unsigned short hnum,
+ int dif)
+{
+ int score = -1;
+
+ if (net_eq(sock_net(sk), net) && udp_sk(sk)->udp_port_hash == hnum &&
+ sk->sk_family == PF_INET6) {
+ struct ipv6_pinfo *np = inet6_sk(sk);
+ struct inet_sock *inet = inet_sk(sk);
+
+ if (!ipv6_addr_equal(&np->rcv_saddr, daddr))
+ return -1;
+ score = 0;
+ if (inet->inet_dport) {
+ if (inet->inet_dport != sport)
+ return -1;
+ score++;
+ }
+ if (!ipv6_addr_any(&np->daddr)) {
+ if (!ipv6_addr_equal(&np->daddr, saddr))
+ return -1;
+ score++;
+ }
+ if (sk->sk_bound_dev_if) {
+ if (sk->sk_bound_dev_if != dif)
+ return -1;
+ score++;
+ }
+ }
+ return score;
+}
+
+#define udp_portaddr_for_each_entry_rcu(__sk, node, list) \
+ hlist_nulls_for_each_entry_rcu(__sk, node, list, __sk_common.skc_portaddr_node)
+
+/* called with read_rcu_lock() */
+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 sock *sk, *result;
+ struct hlist_nulls_node *node;
+ int score, badness;
+
+begin:
+ result = NULL;
+ badness = -1;
+ udp_portaddr_for_each_entry_rcu(sk, node, &hslot2->head) {
+ score = compute_score2(sk, net, saddr, sport,
+ daddr, hnum, dif);
+ if (score > badness) {
+ result = sk;
+ badness = score;
+ if (score == SCORE2_MAX)
+ goto exact_match;
+ }
+ }
+ /*
+ * if the nulls value we got at the end of this lookup is
+ * not the expected one, we must restart lookup.
+ * We probably met an item that was moved to another chain.
+ */
+ if (get_nulls_value(node) != slot2)
+ goto begin;
+
+ if (result) {
+exact_match:
+ if (unlikely(!atomic_inc_not_zero(&result->sk_refcnt)))
+ result = NULL;
+ else if (unlikely(compute_score2(result, net, saddr, sport,
+ daddr, hnum, dif) < badness)) {
+ sock_put(result);
+ goto begin;
+ }
+ }
+ return result;
+}
+
static struct sock *__udp6_lib_lookup(struct net *net,
struct in6_addr *saddr, __be16 sport,
struct in6_addr *daddr, __be16 dport,
@@ -154,11 +236,35 @@ static struct sock *__udp6_lib_lookup(struct net *net,
struct sock *sk, *result;
struct hlist_nulls_node *node;
unsigned short hnum = ntohs(dport);
- unsigned int hash = udp_hashfn(net, hnum, udptable->mask);
- struct udp_hslot *hslot = &udptable->hash[hash];
+ unsigned int hash2, slot2, slot = udp_hashfn(net, hnum, udptable->mask);
+ struct udp_hslot *hslot2, *hslot = &udptable->hash[slot];
int score, badness;
rcu_read_lock();
+ if (hslot->count > 10) {
+ hash2 = udp6_portaddr_hash(net, daddr, hnum);
+ slot2 = hash2 & udptable->mask;
+ hslot2 = &udptable->hash2[slot2];
+ if (hslot->count < hslot2->count)
+ goto begin;
+
+ result = udp6_lib_lookup2(net, saddr, sport,
+ daddr, hnum, dif,
+ hslot2, slot2);
+ if (!result) {
+ hash2 = udp6_portaddr_hash(net, &in6addr_any, hnum);
+ slot2 = hash2 & udptable->mask;
+ hslot2 = &udptable->hash2[slot2];
+ if (hslot->count < hslot2->count)
+ goto begin;
+
+ result = udp6_lib_lookup2(net, &in6addr_any, sport,
+ daddr, hnum, dif,
+ hslot2, slot2);
+ }
+ rcu_read_unlock();
+ return result;
+ }
begin:
result = NULL;
badness = -1;
@@ -174,7 +280,7 @@ begin:
* not the expected one, we must restart lookup.
* We probably met an item that was moved to another chain.
*/
- if (get_nulls_value(node) != hash)
+ if (get_nulls_value(node) != slot)
goto begin;
if (result) {