1 files changed, 93 insertions, 101 deletions

diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index f212abe745bc..b7d43caaa9c8 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -87,18 +87,20 @@ static void update_route(struct bat_priv *bat_priv,
                          struct neigh_node *neigh_node,
                          unsigned char *hna_buff, int hna_buff_len)
 {
-        struct neigh_node *neigh_node_tmp;
+        struct neigh_node *curr_router;
+
+        curr_router = orig_node_get_router(orig_node);
 
         /* route deleted */
-        if ((orig_node->router) && (!neigh_node)) {
+        if ((curr_router) && (!neigh_node)) {
 
                 bat_dbg(DBG_ROUTES, bat_priv, "Deleting route towards: %pM\n",
                         orig_node->orig);
                 hna_global_del_orig(bat_priv, orig_node,
                                     "originator timed out");
 
-                /* route added */
-        } else if ((!orig_node->router) && (neigh_node)) {
+        /* route added */
+        } else if ((!curr_router) && (neigh_node)) {
 
                 bat_dbg(DBG_ROUTES, bat_priv,
                         "Adding route towards: %pM (via %pM)\n",
@@ -106,21 +108,29 @@ static void update_route(struct bat_priv *bat_priv,
                 hna_global_add_orig(bat_priv, orig_node,
                                     hna_buff, hna_buff_len);
 
-                /* route changed */
+        /* route changed */
         } else {
                 bat_dbg(DBG_ROUTES, bat_priv,
                         "Changing route towards: %pM "
                         "(now via %pM - was via %pM)\n",
                         orig_node->orig, neigh_node->addr,
-                        orig_node->router->addr);
+                        curr_router->addr);
         }
 
+        if (curr_router)
+                neigh_node_free_ref(curr_router);
+
+        /* increase refcount of new best neighbor */
         if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount))
                 neigh_node = NULL;
-        neigh_node_tmp = orig_node->router;
-        orig_node->router = neigh_node;
-        if (neigh_node_tmp)
-                neigh_node_free_ref(neigh_node_tmp);
+
+        spin_lock_bh(&orig_node->neigh_list_lock);
+        rcu_assign_pointer(orig_node->router, neigh_node);
+        spin_unlock_bh(&orig_node->neigh_list_lock);
+
+        /* decrease refcount of previous best neighbor */
+        if (curr_router)
+                neigh_node_free_ref(curr_router);
 }
 
 
@@ -128,16 +138,23 @@ void update_routes(struct bat_priv *bat_priv, struct orig_node *orig_node,
                    struct neigh_node *neigh_node, unsigned char *hna_buff,
                    int hna_buff_len)
 {
+        struct neigh_node *router = NULL;
 
         if (!orig_node)
-                return;
+                goto out;
+
+        router = orig_node_get_router(orig_node);
 
-        if (orig_node->router != neigh_node)
+        if (router != neigh_node)
                 update_route(bat_priv, orig_node, neigh_node,
                              hna_buff, hna_buff_len);
         /* may be just HNA changed */
         else
                 update_HNA(bat_priv, orig_node, hna_buff, hna_buff_len);
+
+out:
+        if (router)
+                neigh_node_free_ref(router);
 }
 
 static int is_bidirectional_neigh(struct orig_node *orig_node,
@@ -288,8 +305,8 @@ static void bonding_candidate_add(struct orig_node *orig_node,
                                   struct neigh_node *neigh_node)
 {
         struct hlist_node *node;
-        struct neigh_node *tmp_neigh_node;
-        uint8_t best_tq, interference_candidate = 0;
+        struct neigh_node *tmp_neigh_node, *router = NULL;
+        uint8_t interference_candidate = 0;
 
         spin_lock_bh(&orig_node->neigh_list_lock);
 
@@ -298,13 +315,12 @@ static void bonding_candidate_add(struct orig_node *orig_node,
                          neigh_node->orig_node->primary_addr))
                 goto candidate_del;
 
-        if (!orig_node->router)
+        router = orig_node_get_router(orig_node);
+        if (!router)
                 goto candidate_del;
 
-        best_tq = orig_node->router->tq_avg;
-
         /* ... and is good enough to be considered */
-        if (neigh_node->tq_avg < best_tq - BONDING_TQ_THRESHOLD)
+        if (neigh_node->tq_avg < router->tq_avg - BONDING_TQ_THRESHOLD)
                 goto candidate_del;
 
         /**
@@ -350,7 +366,9 @@ candidate_del:
 
 out:
         spin_unlock_bh(&orig_node->neigh_list_lock);
-        return;
+
+        if (router)
+                neigh_node_free_ref(router);
 }
 
 /* copy primary address for bonding */
@@ -373,6 +391,7 @@ static void update_orig(struct bat_priv *bat_priv,
                         char is_duplicate)
 {
         struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
+        struct neigh_node *router = NULL;
         struct orig_node *orig_node_tmp;
         struct hlist_node *node;
         int tmp_hna_buff_len;
@@ -441,19 +460,18 @@ static void update_orig(struct bat_priv *bat_priv,
 
         /* if this neighbor already is our next hop there is nothing
          * to change */
-        if (orig_node->router == neigh_node)
+        router = orig_node_get_router(orig_node);
+        if (router == neigh_node)
                 goto update_hna;
 
         /* if this neighbor does not offer a better TQ we won't consider it */
-        if ((orig_node->router) &&
-            (orig_node->router->tq_avg > neigh_node->tq_avg))
+        if (router && (router->tq_avg > neigh_node->tq_avg))
                 goto update_hna;
 
         /* if the TQ is the same and the link not more symetric we
          * won't consider it either */
-        if ((orig_node->router) &&
-             (neigh_node->tq_avg == orig_node->router->tq_avg)) {
-                orig_node_tmp = orig_node->router->orig_node;
+        if (router && (neigh_node->tq_avg == router->tq_avg)) {
+                orig_node_tmp = router->orig_node;
                 spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
                 bcast_own_sum_orig =
                         orig_node_tmp->bcast_own_sum[if_incoming->if_num];
@@ -474,7 +492,7 @@ static void update_orig(struct bat_priv *bat_priv,
         goto update_gw;
 
 update_hna:
-        update_routes(bat_priv, orig_node, orig_node->router,
+        update_routes(bat_priv, orig_node, router,
                       hna_buff, tmp_hna_buff_len);
 
 update_gw:
@@ -496,6 +514,8 @@ unlock:
 out:
         if (neigh_node)
                 neigh_node_free_ref(neigh_node);
+        if (router)
+                neigh_node_free_ref(router);
 }
 
 /* checks whether the host restarted and is in the protection time.
@@ -603,6 +623,8 @@ void receive_bat_packet(struct ethhdr *ethhdr,
         struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
         struct hard_iface *hard_iface;
         struct orig_node *orig_neigh_node, *orig_node;
+        struct neigh_node *router = NULL, *router_router = NULL;
+        struct neigh_node *orig_neigh_router = NULL;
         char has_directlink_flag;
         char is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
         char is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
@@ -747,14 +769,15 @@ void receive_bat_packet(struct ethhdr *ethhdr,
                 goto out;
         }
 
+        router = orig_node_get_router(orig_node);
+        if (router)
+                router_router = orig_node_get_router(router->orig_node);
+
         /* avoid temporary routing loops */
-        if ((orig_node->router) &&
-            (orig_node->router->orig_node->router) &&
-            (compare_eth(orig_node->router->addr,
-                         batman_packet->prev_sender)) &&
+        if (router && router_router &&
+            (compare_eth(router->addr, batman_packet->prev_sender)) &&
             !(compare_eth(batman_packet->orig, batman_packet->prev_sender)) &&
-            (compare_eth(orig_node->router->addr,
-                         orig_node->router->orig_node->router->addr))) {
+            (compare_eth(router->addr, router_router->addr))) {
                 bat_dbg(DBG_BATMAN, bat_priv,
                         "Drop packet: ignoring all rebroadcast packets that "
                         "may make me loop (sender: %pM)\n", ethhdr->h_source);
@@ -769,9 +792,11 @@ void receive_bat_packet(struct ethhdr *ethhdr,
         if (!orig_neigh_node)
                 goto out;
 
+        orig_neigh_router = orig_node_get_router(orig_neigh_node);
+
         /* drop packet if sender is not a direct neighbor and if we
          * don't route towards it */
-        if (!is_single_hop_neigh && (!orig_neigh_node->router)) {
+        if (!is_single_hop_neigh && (!orig_neigh_router)) {
                 bat_dbg(DBG_BATMAN, bat_priv,
                         "Drop packet: OGM via unknown neighbor!\n");
                 goto out_neigh;
@@ -825,6 +850,13 @@ out_neigh:
         if ((orig_neigh_node) && (!is_single_hop_neigh))
                 orig_node_free_ref(orig_neigh_node);
 out:
+        if (router)
+                neigh_node_free_ref(router);
+        if (router_router)
+                neigh_node_free_ref(router_router);
+        if (orig_neigh_router)
+                neigh_node_free_ref(orig_neigh_router);
+
         orig_node_free_ref(orig_node);
 }
 
@@ -869,7 +901,7 @@ static int recv_my_icmp_packet(struct bat_priv *bat_priv,
                                struct sk_buff *skb, size_t icmp_len)
 {
         struct orig_node *orig_node = NULL;
-        struct neigh_node *neigh_node = NULL;
+        struct neigh_node *router = NULL;
         struct icmp_packet_rr *icmp_packet;
         int ret = NET_RX_DROP;
 
@@ -886,23 +918,13 @@ static int recv_my_icmp_packet(struct bat_priv *bat_priv,
 
         /* answer echo request (ping) */
         /* get routing information */
-        rcu_read_lock();
         orig_node = orig_hash_find(bat_priv, icmp_packet->orig);
-
         if (!orig_node)
-                goto unlock;
-
-        neigh_node = orig_node->router;
-
-        if (!neigh_node)
-                goto unlock;
-
-        if (!atomic_inc_not_zero(&neigh_node->refcount)) {
-                neigh_node = NULL;
-                goto unlock;
-        }
+                goto out;
 
-        rcu_read_unlock();
+        router = orig_node_get_router(orig_node);
+        if (!router)
+                goto out;
 
         /* create a copy of the skb, if needed, to modify it. */
         if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
@@ -916,15 +938,12 @@ static int recv_my_icmp_packet(struct bat_priv *bat_priv,
         icmp_packet->msg_type = ECHO_REPLY;
         icmp_packet->ttl = TTL;
 
-        send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
+        send_skb_packet(skb, router->if_incoming, router->addr);
         ret = NET_RX_SUCCESS;
-        goto out;
 
-unlock:
-        rcu_read_unlock();
 out:
-        if (neigh_node)
-                neigh_node_free_ref(neigh_node);
+        if (router)
+                neigh_node_free_ref(router);
         if (orig_node)
                 orig_node_free_ref(orig_node);
         return ret;
@@ -934,7 +953,7 @@ static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv,
                                   struct sk_buff *skb)
 {
         struct orig_node *orig_node = NULL;
-        struct neigh_node *neigh_node = NULL;
+        struct neigh_node *router = NULL;
         struct icmp_packet *icmp_packet;
         int ret = NET_RX_DROP;
 
@@ -952,23 +971,13 @@ static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv,
                 goto out;
 
         /* get routing information */
-        rcu_read_lock();
         orig_node = orig_hash_find(bat_priv, icmp_packet->orig);
-
         if (!orig_node)
-                goto unlock;
-
-        neigh_node = orig_node->router;
-
-        if (!neigh_node)
-                goto unlock;
-
-        if (!atomic_inc_not_zero(&neigh_node->refcount)) {
-                neigh_node = NULL;
-                goto unlock;
-        }
+                goto out;
 
-        rcu_read_unlock();
+        router = orig_node_get_router(orig_node);
+        if (!router)
+                goto out;
 
         /* create a copy of the skb, if needed, to modify it. */
         if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
@@ -982,15 +991,12 @@ static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv,
         icmp_packet->msg_type = TTL_EXCEEDED;
         icmp_packet->ttl = TTL;
 
-        send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
+        send_skb_packet(skb, router->if_incoming, router->addr);
         ret = NET_RX_SUCCESS;
-        goto out;
 
-unlock:
-        rcu_read_unlock();
 out:
-        if (neigh_node)
-                neigh_node_free_ref(neigh_node);
+        if (router)
+                neigh_node_free_ref(router);
         if (orig_node)
                 orig_node_free_ref(orig_node);
         return ret;
@@ -1003,7 +1009,7 @@ int recv_icmp_packet(struct sk_buff *skb, struct hard_iface *recv_if)
         struct icmp_packet_rr *icmp_packet;
         struct ethhdr *ethhdr;
         struct orig_node *orig_node = NULL;
-        struct neigh_node *neigh_node = NULL;
+        struct neigh_node *router = NULL;
         int hdr_size = sizeof(struct icmp_packet);
         int ret = NET_RX_DROP;
 
@@ -1050,23 +1056,13 @@ int recv_icmp_packet(struct sk_buff *skb, struct hard_iface *recv_if)
                 return recv_icmp_ttl_exceeded(bat_priv, skb);
 
         /* get routing information */
-        rcu_read_lock();
         orig_node = orig_hash_find(bat_priv, icmp_packet->dst);
-
         if (!orig_node)
-                goto unlock;
-
-        neigh_node = orig_node->router;
-
-        if (!neigh_node)
-                goto unlock;
-
-        if (!atomic_inc_not_zero(&neigh_node->refcount)) {
-                neigh_node = NULL;
-                goto unlock;
-        }
+                goto out;
 
-        rcu_read_unlock();
+        router = orig_node_get_router(orig_node);
+        if (!router)
+                goto out;
 
         /* create a copy of the skb, if needed, to modify it. */
         if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
@@ -1078,15 +1074,12 @@ int recv_icmp_packet(struct sk_buff *skb, struct hard_iface *recv_if)
         icmp_packet->ttl--;
 
         /* route it */
-        send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
+        send_skb_packet(skb, router->if_incoming, router->addr);
         ret = NET_RX_SUCCESS;
-        goto out;
 
-unlock:
-        rcu_read_unlock();
 out:
-        if (neigh_node)
-                neigh_node_free_ref(neigh_node);
+        if (router)
+                neigh_node_free_ref(router);
         if (orig_node)
                 orig_node_free_ref(orig_node);
         return ret;
@@ -1208,7 +1201,8 @@ struct neigh_node *find_router(struct bat_priv *bat_priv,
         if (!orig_node)
                 return NULL;
 
-        if (!orig_node->router)
+        router = orig_node_get_router(orig_node);
+        if (!router)
                 return NULL;
 
         /* without bonding, the first node should
@@ -1217,9 +1211,8 @@ struct neigh_node *find_router(struct bat_priv *bat_priv,
 
         rcu_read_lock();
         /* select default router to output */
-        router = orig_node->router;
-        router_orig = orig_node->router->orig_node;
-        if (!router_orig || !atomic_inc_not_zero(&router->refcount)) {
+        router_orig = router->orig_node;
+        if (!router_orig) {
                 rcu_read_unlock();
                 return NULL;
         }
@@ -1251,7 +1244,6 @@ struct neigh_node *find_router(struct bat_priv *bat_priv,
         if (atomic_read(&primary_orig_node->bond_candidates) < 2)
                 goto return_router;
 
-
         /* all nodes between should choose a candidate which
          * is is not on the interface where the packet came
          * in. */