l2tp: unhash l2tp sessions on delete, not on free

[karo-tx-linux.git] / net / l2tp / l2tp_core.c

diff --git a/net/l2tp/l2tp_core.c b/net/l2tp/l2tp_core.c
index 97d30ac67c885f37b7a6596955b4e2bf7a0d3f2a..8aecf5df66569a6ca0ae1b8921e20954d6812336 100644 (file)
--- a/net/l2tp/l2tp_core.c
+++ b/net/l2tp/l2tp_core.c
@@ -1316,26 +1316,12 @@ again:
 
                        hlist_del_init(&session->hlist);
 
-                       /* Since we should hold the sock lock while
-                        * doing any unbinding, we need to release the
-                        * lock we're holding before taking that lock.
-                        * Hold a reference to the sock so it doesn't
-                        * disappear as we're jumping between locks.
-                        */
                        if (session->ref != NULL)
                                (*session->ref)(session);
 
                        write_unlock_bh(&tunnel->hlist_lock);
 
-                       if (tunnel->version != L2TP_HDR_VER_2) {
-                               struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net);
-
-                               spin_lock_bh(&pn->l2tp_session_hlist_lock);
-                               hlist_del_init_rcu(&session->global_hlist);
-                               spin_unlock_bh(&pn->l2tp_session_hlist_lock);
-                               synchronize_rcu();
-                       }
-
+                       __l2tp_session_unhash(session);
                        l2tp_session_queue_purge(session);
 
                        if (session->session_close != NULL)
@@ -1732,64 +1718,71 @@ EXPORT_SYMBOL_GPL(l2tp_tunnel_delete);
  */
 void l2tp_session_free(struct l2tp_session *session)
 {
-       struct l2tp_tunnel *tunnel;
+       struct l2tp_tunnel *tunnel = session->tunnel;
 
        BUG_ON(atomic_read(&session->ref_count) != 0);
 
-       tunnel = session->tunnel;
-       if (tunnel != NULL) {
+       if (tunnel) {
                BUG_ON(tunnel->magic != L2TP_TUNNEL_MAGIC);
+               if (session->session_id != 0)
+                       atomic_dec(&l2tp_session_count);
+               sock_put(tunnel->sock);
+               session->tunnel = NULL;
+               l2tp_tunnel_dec_refcount(tunnel);
+       }
+
+       kfree(session);
+
+       return;
+}
+EXPORT_SYMBOL_GPL(l2tp_session_free);
+
+/* Remove an l2tp session from l2tp_core's hash lists.
+ * Provides a tidyup interface for pseudowire code which can't just route all
+ * shutdown via. l2tp_session_delete and a pseudowire-specific session_close
+ * callback.
+ */
+void __l2tp_session_unhash(struct l2tp_session *session)
+{
+       struct l2tp_tunnel *tunnel = session->tunnel;
 
-               /* Delete the session from the hash */
+       /* Remove the session from core hashes */
+       if (tunnel) {
+               /* Remove from the per-tunnel hash */
                write_lock_bh(&tunnel->hlist_lock);
                hlist_del_init(&session->hlist);
                write_unlock_bh(&tunnel->hlist_lock);
 
-               /* Unlink from the global hash if not L2TPv2 */
+               /* For L2TPv3 we have a per-net hash: remove from there, too */
                if (tunnel->version != L2TP_HDR_VER_2) {
                        struct l2tp_net *pn = l2tp_pernet(tunnel->l2tp_net);
-
                        spin_lock_bh(&pn->l2tp_session_hlist_lock);
                        hlist_del_init_rcu(&session->global_hlist);
                        spin_unlock_bh(&pn->l2tp_session_hlist_lock);
                        synchronize_rcu();
                }
-
-               if (session->session_id != 0)
-                       atomic_dec(&l2tp_session_count);
-
-               sock_put(tunnel->sock);
-
-               /* This will delete the tunnel context if this
-                * is the last session on the tunnel.
-                */
-               session->tunnel = NULL;
-               l2tp_tunnel_dec_refcount(tunnel);
        }
-
-       kfree(session);
-
-       return;
 }
-EXPORT_SYMBOL_GPL(l2tp_session_free);
+EXPORT_SYMBOL_GPL(__l2tp_session_unhash);
 
 /* This function is used by the netlink SESSION_DELETE command and by
    pseudowire modules.
  */
 int l2tp_session_delete(struct l2tp_session *session)
 {
+       if (session->ref)
+               (*session->ref)(session);
+       __l2tp_session_unhash(session);
        l2tp_session_queue_purge(session);
-
        if (session->session_close != NULL)
                (*session->session_close)(session);
-
+       if (session->deref)
+               (*session->ref)(session);
        l2tp_session_dec_refcount(session);
-
        return 0;
 }
 EXPORT_SYMBOL_GPL(l2tp_session_delete);
 
-
 /* We come here whenever a session's send_seq, cookie_len or
  * l2specific_len parameters are set.
  */