sctp: apply rhashtable api to send/recv path

apply lookup apis to two functions, for __sctp_endpoint_lookup_assoc
and __sctp_lookup_association, it's invoked in the protection of sock
lock, it will be safe, but sctp_lookup_association need to call
rcu_read_lock() and to detect the t->dead to protect it.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 29 deletions

diff --git a/net/sctp/input.c b/net/sctp/input.c
index bac8278b176b..6f075d835764 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -981,38 +981,19 @@ static struct sctp_association *__sctp_lookup_association(
                                         const union sctp_addr *peer,
                                         struct sctp_transport **pt)
 {
-        struct sctp_hashbucket *head;
-        struct sctp_ep_common *epb;
-        struct sctp_association *asoc;
-        struct sctp_transport *transport;
-        int hash;
+        struct sctp_transport *t;
 
-        /* Optimize here for direct hit, only listening connections can
-         * have wildcards anyways.
-         */
-        hash = sctp_assoc_hashfn(net, ntohs(local->v4.sin_port),
-                                 ntohs(peer->v4.sin_port));
-        head = &sctp_assoc_hashtable[hash];
-        read_lock(&head->lock);
-        sctp_for_each_hentry(epb, &head->chain) {
-                asoc = sctp_assoc(epb);
-                transport = sctp_assoc_is_match(asoc, net, local, peer);
-                if (transport)
-                        goto hit;
-        }
+        t = sctp_addrs_lookup_transport(net, local, peer);
+        if (!t || t->dead || t->asoc->temp)
+                return NULL;
 
-        read_unlock(&head->lock);
+        sctp_association_hold(t->asoc);
+        *pt = t;
 
-        return NULL;
-
-hit:
-        *pt = transport;
-        sctp_association_hold(asoc);
-        read_unlock(&head->lock);
-        return asoc;
+        return t->asoc;
 }
 
-/* Look up an association. BH-safe. */
+/* Look up an association. protected by RCU read lock */
 static
 struct sctp_association *sctp_lookup_association(struct net *net,
                                                  const union sctp_addr *laddr,
@@ -1021,9 +1002,9 @@ struct sctp_association *sctp_lookup_association(struct net *net,
 {
         struct sctp_association *asoc;
 
-        local_bh_disable();
+        rcu_read_lock();
         asoc = __sctp_lookup_association(net, laddr, paddr, transportp);
-        local_bh_enable();
+        rcu_read_unlock();
 
         return asoc;
 }