Merge branch 'batman-adv/next' of git://git.open-mesh.org/ecsv/linux-merge

Author: davem330

net/batman-adv/aggregation.c

@@ -95,7 +95,6 @@ static bool can_aggregate_with(struct batman_packet *new_batman_packet,
 	return false;
 }
 
-#define atomic_dec_not_zero(v)          atomic_add_unless((v), -1, 0)
 /* create a new aggregated packet and add this packet to it */
 static void new_aggregated_packet(unsigned char *packet_buff, int packet_len,
 				  unsigned long send_time, bool direct_link,

net/batman-adv/gateway_client.c

@@ -127,7 +127,7 @@ void gw_election(struct bat_priv *bat_priv)
 		return;
 
 	curr_gw = gw_get_selected_gw_node(bat_priv);
-	if (!curr_gw)
+	if (curr_gw)
 		goto out;
 
 	rcu_read_lock();
@@ -310,9 +310,13 @@ void gw_node_update(struct bat_priv *bat_priv,
 	struct hlist_node *node;
 	struct gw_node *gw_node, *curr_gw;
 
+	/**
+	 * Note: We don't need a NULL check here, since curr_gw never gets
+	 * dereferenced. If curr_gw is NULL we also should not exit as we may
+	 * have this gateway in our list (duplication check!) even though we
+	 * have no currently selected gateway.
+	 */
 	curr_gw = gw_get_selected_gw_node(bat_priv);
-	if (!curr_gw)
-		goto out;
 
 	rcu_read_lock();
 	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
@@ -350,7 +354,7 @@ void gw_node_update(struct bat_priv *bat_priv,
 	gw_deselect(bat_priv);
 unlock:
 	rcu_read_unlock();
-out:
+
 	if (curr_gw)
 		gw_node_free_ref(curr_gw);
 }
@@ -435,30 +439,32 @@ int gw_client_seq_print_text(struct seq_file *seq, void *offset)
 {
 	struct net_device *net_dev = (struct net_device *)seq->private;
 	struct bat_priv *bat_priv = netdev_priv(net_dev);
+	struct hard_iface *primary_if;
 	struct gw_node *gw_node;
 	struct hlist_node *node;
-	int gw_count = 0;
+	int gw_count = 0, ret = 0;
 
-	if (!bat_priv->primary_if) {
-
-		return seq_printf(seq, "BATMAN mesh %s disabled - please "
-				  "specify interfaces to enable it\n",
-				  net_dev->name);
+	primary_if = primary_if_get_selected(bat_priv);
+	if (!primary_if) {
+		ret = seq_printf(seq, "BATMAN mesh %s disabled - please "
+				 "specify interfaces to enable it\n",
+				 net_dev->name);
+		goto out;
 	}
 
-	if (bat_priv->primary_if->if_status != IF_ACTIVE) {
-
-		return seq_printf(seq, "BATMAN mesh %s disabled - "
-				       "primary interface not active\n",
-				       net_dev->name);
+	if (primary_if->if_status != IF_ACTIVE) {
+		ret = seq_printf(seq, "BATMAN mesh %s disabled - "
+				 "primary interface not active\n",
+				 net_dev->name);
+		goto out;
 	}
 
 	seq_printf(seq, "      %-12s (%s/%i) %17s [%10s]: gw_class ... "
 		   "[B.A.T.M.A.N. adv %s%s, MainIF/MAC: %s/%pM (%s)]\n",
 		   "Gateway", "#", TQ_MAX_VALUE, "Nexthop",
 		   "outgoingIF", SOURCE_VERSION, REVISION_VERSION_STR,
-		   bat_priv->primary_if->net_dev->name,
-		   bat_priv->primary_if->net_dev->dev_addr, net_dev->name);
+		   primary_if->net_dev->name,
+		   primary_if->net_dev->dev_addr, net_dev->name);
 
 	rcu_read_lock();
 	hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw_list, list) {
@@ -476,7 +482,10 @@ int gw_client_seq_print_text(struct seq_file *seq, void *offset)
 	if (gw_count == 0)
 		seq_printf(seq, "No gateways in range ...\n");
 
-	return 0;
+out:
+	if (primary_if)
+		hardif_free_ref(primary_if);
+	return ret;
 }
 
 int gw_is_target(struct bat_priv *bat_priv, struct sk_buff *skb)

net/batman-adv/hard-interface.c

@@ -110,47 +110,60 @@ static struct hard_iface *hardif_get_active(struct net_device *soft_iface)
 	return hard_iface;
 }
 
-static void update_primary_addr(struct bat_priv *bat_priv)
+static void primary_if_update_addr(struct bat_priv *bat_priv)
 {
 	struct vis_packet *vis_packet;
+	struct hard_iface *primary_if;
+
+	primary_if = primary_if_get_selected(bat_priv);
+	if (!primary_if)
+		goto out;
 
 	vis_packet = (struct vis_packet *)
 				bat_priv->my_vis_info->skb_packet->data;
-	memcpy(vis_packet->vis_orig,
-	       bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
+	memcpy(vis_packet->vis_orig, primary_if->net_dev->dev_addr, ETH_ALEN);
 	memcpy(vis_packet->sender_orig,
-	       bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
+	       primary_if->net_dev->dev_addr, ETH_ALEN);
+
+out:
+	if (primary_if)
+		hardif_free_ref(primary_if);
 }
 
-static void set_primary_if(struct bat_priv *bat_priv,
-			   struct hard_iface *hard_iface)
+static void primary_if_select(struct bat_priv *bat_priv,
+			      struct hard_iface *new_hard_iface)
 {
+	struct hard_iface *curr_hard_iface;
 	struct batman_packet *batman_packet;
-	struct hard_iface *old_if;
 
-	if (hard_iface && !atomic_inc_not_zero(&hard_iface->refcount))
-		hard_iface = NULL;
+	spin_lock_bh(&hardif_list_lock);
 
-	old_if = bat_priv->primary_if;
-	bat_priv->primary_if = hard_iface;
+	if (new_hard_iface && !atomic_inc_not_zero(&new_hard_iface->refcount))
+		new_hard_iface = NULL;
 
-	if (old_if)
-		hardif_free_ref(old_if);
+	curr_hard_iface = bat_priv->primary_if;
+	rcu_assign_pointer(bat_priv->primary_if, new_hard_iface);
 
-	if (!bat_priv->primary_if)
-		return;
+	if (curr_hard_iface)
+		hardif_free_ref(curr_hard_iface);
 
-	batman_packet = (struct batman_packet *)(hard_iface->packet_buff);
+	if (!new_hard_iface)
+		goto out;
+
+	batman_packet = (struct batman_packet *)(new_hard_iface->packet_buff);
 	batman_packet->flags = PRIMARIES_FIRST_HOP;
 	batman_packet->ttl = TTL;
 
-	update_primary_addr(bat_priv);
+	primary_if_update_addr(bat_priv);
 
 	/***
 	 * hacky trick to make sure that we send the HNA information via
 	 * our new primary interface
 	 */
 	atomic_set(&bat_priv->hna_local_changed, 1);
+
+out:
+	spin_unlock_bh(&hardif_list_lock);
 }
 
 static bool hardif_is_iface_up(struct hard_iface *hard_iface)
@@ -236,9 +249,10 @@ void update_min_mtu(struct net_device *soft_iface)
 static void hardif_activate_interface(struct hard_iface *hard_iface)
 {
 	struct bat_priv *bat_priv;
+	struct hard_iface *primary_if = NULL;
 
 	if (hard_iface->if_status != IF_INACTIVE)
-		return;
+		goto out;
 
 	bat_priv = netdev_priv(hard_iface->soft_iface);
 
@@ -249,14 +263,18 @@ static void hardif_activate_interface(struct hard_iface *hard_iface)
 	 * the first active interface becomes our primary interface or
 	 * the next active interface after the old primay interface was removed
 	 */
-	if (!bat_priv->primary_if)
-		set_primary_if(bat_priv, hard_iface);
+	primary_if = primary_if_get_selected(bat_priv);
+	if (!primary_if)
+		primary_if_select(bat_priv, hard_iface);
 
 	bat_info(hard_iface->soft_iface, "Interface activated: %s\n",
 		 hard_iface->net_dev->name);
 
 	update_min_mtu(hard_iface->soft_iface);
-	return;
+
+out:
+	if (primary_if)
+		hardif_free_ref(primary_if);
 }
 
 static void hardif_deactivate_interface(struct hard_iface *hard_iface)
@@ -386,12 +404,13 @@ int hardif_enable_interface(struct hard_iface *hard_iface, char *iface_name)
 void hardif_disable_interface(struct hard_iface *hard_iface)
 {
 	struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+	struct hard_iface *primary_if = NULL;
 
 	if (hard_iface->if_status == IF_ACTIVE)
 		hardif_deactivate_interface(hard_iface);
 
 	if (hard_iface->if_status != IF_INACTIVE)
-		return;
+		goto out;
 
 	bat_info(hard_iface->soft_iface, "Removing interface: %s\n",
 		 hard_iface->net_dev->name);
@@ -400,11 +419,12 @@ void hardif_disable_interface(struct hard_iface *hard_iface)
 	bat_priv->num_ifaces--;
 	orig_hash_del_if(hard_iface, bat_priv->num_ifaces);
 
-	if (hard_iface == bat_priv->primary_if) {
+	primary_if = primary_if_get_selected(bat_priv);
+	if (hard_iface == primary_if) {
 		struct hard_iface *new_if;
 
 		new_if = hardif_get_active(hard_iface->soft_iface);
-		set_primary_if(bat_priv, new_if);
+		primary_if_select(bat_priv, new_if);
 
 		if (new_if)
 			hardif_free_ref(new_if);
@@ -425,6 +445,10 @@ void hardif_disable_interface(struct hard_iface *hard_iface)
 
 	hard_iface->soft_iface = NULL;
 	hardif_free_ref(hard_iface);
+
+out:
+	if (primary_if)
+		hardif_free_ref(primary_if);
 }
 
 static struct hard_iface *hardif_add_interface(struct net_device *net_dev)
@@ -514,6 +538,7 @@ static int hard_if_event(struct notifier_block *this,
 {
 	struct net_device *net_dev = (struct net_device *)ptr;
 	struct hard_iface *hard_iface = hardif_get_by_netdev(net_dev);
+	struct hard_iface *primary_if = NULL;
 	struct bat_priv *bat_priv;
 
 	if (!hard_iface && event == NETDEV_REGISTER)
@@ -549,8 +574,12 @@ static int hard_if_event(struct notifier_block *this,
 		update_mac_addresses(hard_iface);
 
 		bat_priv = netdev_priv(hard_iface->soft_iface);
-		if (hard_iface == bat_priv->primary_if)
-			update_primary_addr(bat_priv);
+		primary_if = primary_if_get_selected(bat_priv);
+		if (!primary_if)
+			goto hardif_put;
+
+		if (hard_iface == primary_if)
+			primary_if_update_addr(bat_priv);
 		break;
 	default:
 		break;
@@ -559,6 +588,8 @@ static int hard_if_event(struct notifier_block *this,
 hardif_put:
 	hardif_free_ref(hard_iface);
 out:
+	if (primary_if)
+		hardif_free_ref(primary_if);
 	return NOTIFY_DONE;
 }
 

net/batman-adv/hard-interface.h

@@ -45,4 +45,22 @@ static inline void hardif_free_ref(struct hard_iface *hard_iface)
 		call_rcu(&hard_iface->rcu, hardif_free_rcu);
 }
 
+static inline struct hard_iface *primary_if_get_selected(
+						struct bat_priv *bat_priv)
+{
+	struct hard_iface *hard_iface;
+
+	rcu_read_lock();
+	hard_iface = rcu_dereference(bat_priv->primary_if);
+	if (!hard_iface)
+		goto out;
+
+	if (!atomic_inc_not_zero(&hard_iface->refcount))
+		hard_iface = NULL;
+
+out:
+	rcu_read_unlock();
+	return hard_iface;
+}
+
 #endif /* _NET_BATMAN_ADV_HARD_INTERFACE_H_ */

net/batman-adv/icmp_socket.c

@@ -153,6 +153,7 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
 {
 	struct socket_client *socket_client = file->private_data;
 	struct bat_priv *bat_priv = socket_client->bat_priv;
+	struct hard_iface *primary_if = NULL;
 	struct sk_buff *skb;
 	struct icmp_packet_rr *icmp_packet;
 
@@ -167,15 +168,21 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
 		return -EINVAL;
 	}
 
-	if (!bat_priv->primary_if)
-		return -EFAULT;
+	primary_if = primary_if_get_selected(bat_priv);
+
+	if (!primary_if) {
+		len = -EFAULT;
+		goto out;
+	}
 
 	if (len >= sizeof(struct icmp_packet_rr))
 		packet_len = sizeof(struct icmp_packet_rr);
 
 	skb = dev_alloc_skb(packet_len + sizeof(struct ethhdr));
-	if (!skb)
-		return -ENOMEM;
+	if (!skb) {
+		len = -ENOMEM;
+		goto out;
+	}
 
 	skb_reserve(skb, sizeof(struct ethhdr));
 	icmp_packet = (struct icmp_packet_rr *)skb_put(skb, packet_len);
@@ -233,7 +240,7 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
 		goto dst_unreach;
 
 	memcpy(icmp_packet->orig,
-	       bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
+	       primary_if->net_dev->dev_addr, ETH_ALEN);
 
 	if (packet_len == sizeof(struct icmp_packet_rr))
 		memcpy(icmp_packet->rr,
@@ -248,6 +255,8 @@ static ssize_t bat_socket_write(struct file *file, const char __user *buff,
 free_skb:
 	kfree_skb(skb);
 out:
+	if (primary_if)
+		hardif_free_ref(primary_if);
 	if (neigh_node)
 		neigh_node_free_ref(neigh_node);
 	if (orig_node)

net/batman-adv/main.h

@@ -175,4 +175,6 @@ static inline int compare_eth(void *data1, void *data2)
 	return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
 }
 
+#define atomic_dec_not_zero(v)	atomic_add_unless((v), -1, 0)
+
 #endif /* _NET_BATMAN_ADV_MAIN_H_ */