[SCTP]: Fix the SO_REUSEADDR handling to be similar to TCP.

Update the SO_REUSEADDR handling to also check for listen state.  This
was muliple listening server sockets can't be created and they will
not steal packets from each other.

Reported by Paolo Galtieri <pgaltieri@mvista.com>

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 22 insertions, 10 deletions

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index b2ffab62a22..9f1a908776d 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -5020,7 +5020,8 @@ pp_found:
                 struct hlist_node *node;
 
                 SCTP_DEBUG_PRINTK("sctp_get_port() found a possible match\n");
-                if (pp->fastreuse && sk->sk_reuse)
+                if (pp->fastreuse && sk->sk_reuse &&
+                        sk->sk_state != SCTP_SS_LISTENING)
                         goto success;
 
                 /* Run through the list of sockets bound to the port
@@ -5037,7 +5038,8 @@ pp_found:
                         struct sctp_endpoint *ep2;
                         ep2 = sctp_sk(sk2)->ep;
 
-                        if (reuse && sk2->sk_reuse)
+                        if (reuse && sk2->sk_reuse &&
+                            sk2->sk_state != SCTP_SS_LISTENING)
                                 continue;
 
                         if (sctp_bind_addr_match(&ep2->base.bind_addr, addr,
@@ -5058,9 +5060,13 @@ pp_not_found:
          * if sk->sk_reuse is too (that is, if the caller requested
          * SO_REUSEADDR on this socket -sk-).
          */
-        if (hlist_empty(&pp->owner))
-                pp->fastreuse = sk->sk_reuse ? 1 : 0;
-        else if (pp->fastreuse && !sk->sk_reuse)
+        if (hlist_empty(&pp->owner)) {
+                if (sk->sk_reuse && sk->sk_state != SCTP_SS_LISTENING)
+                        pp->fastreuse = 1;
+                else
+                        pp->fastreuse = 0;
+        } else if (pp->fastreuse &&
+                (!sk->sk_reuse || sk->sk_state == SCTP_SS_LISTENING))
                 pp->fastreuse = 0;
 
         /* We are set, so fill up all the data in the hash table
@@ -5068,8 +5074,8 @@ pp_not_found:
          * sockets FIXME: Blurry, NPI (ipg).
          */
 success:
-        inet_sk(sk)->num = snum;
         if (!sctp_sk(sk)->bind_hash) {
+                inet_sk(sk)->num = snum;
                 sk_add_bind_node(sk, &pp->owner);
                 sctp_sk(sk)->bind_hash = pp;
         }
@@ -5142,12 +5148,16 @@ SCTP_STATIC int sctp_seqpacket_listen(struct sock *sk, int backlog)
          * This is not currently spelled out in the SCTP sockets
          * extensions draft, but follows the practice as seen in TCP
          * sockets.
+         *
+         * Additionally, turn off fastreuse flag since we are not listening
          */
+        sk->sk_state = SCTP_SS_LISTENING;
         if (!ep->base.bind_addr.port) {
                 if (sctp_autobind(sk))
                         return -EAGAIN;
-        }
-        sk->sk_state = SCTP_SS_LISTENING;
+        } else
+                sctp_sk(sk)->bind_hash->fastreuse = 0;
+
         sctp_hash_endpoint(ep);
         return 0;
 }
@@ -5185,11 +5195,13 @@ SCTP_STATIC int sctp_stream_listen(struct sock *sk, int backlog)
          * extensions draft, but follows the practice as seen in TCP
          * sockets.
          */
+        sk->sk_state = SCTP_SS_LISTENING;
         if (!ep->base.bind_addr.port) {
                 if (sctp_autobind(sk))
                         return -EAGAIN;
-        }
-        sk->sk_state = SCTP_SS_LISTENING;
+        } else
+                sctp_sk(sk)->bind_hash->fastreuse = 0;
+
         sk->sk_max_ack_backlog = backlog;
         sctp_hash_endpoint(ep);
         return 0;