1 files changed, 100 insertions, 132 deletions

diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index de9955d5224d..7a11b245e9f4 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -1,18 +1,7 @@
-/* Copyright (C) 2009-2017  B.A.T.M.A.N. contributors:
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) B.A.T.M.A.N. contributors:
  *
  * Marek Lindner
- *
- * This program is free software; you can redistribute it and/or
- * modify it under the terms of version 2 of the GNU General Public
- * License as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
 #include "gateway_client.h"
@@ -20,39 +9,37 @@
 
 #include <linux/atomic.h>
 #include <linux/byteorder/generic.h>
+#include <linux/container_of.h>
+#include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/etherdevice.h>
-#include <linux/fs.h>
+#include <linux/gfp.h>
 #include <linux/if_ether.h>
 #include <linux/if_vlan.h>
 #include <linux/in.h>
 #include <linux/ip.h>
 #include <linux/ipv6.h>
-#include <linux/kernel.h>
 #include <linux/kref.h>
 #include <linux/list.h>
+#include <linux/lockdep.h>
 #include <linux/netdevice.h>
 #include <linux/netlink.h>
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
-#include <linux/seq_file.h>
 #include <linux/skbuff.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
+#include <linux/sprintf.h>
 #include <linux/stddef.h>
 #include <linux/udp.h>
-#include <net/sock.h>
+#include <uapi/linux/batadv_packet.h>
 #include <uapi/linux/batman_adv.h>
 
-#include "gateway_common.h"
 #include "hard-interface.h"
 #include "log.h"
 #include "netlink.h"
 #include "originator.h"
-#include "packet.h"
 #include "routing.h"
-#include "soft-interface.h"
-#include "sysfs.h"
 #include "translation-table.h"
 
 /* These are the offsets of the "hw type" and "hw address length" in the dhcp
@@ -68,11 +55,11 @@
 #define BATADV_DHCP_CHADDR_OFFSET	28
 
 /**
- * batadv_gw_node_release - release gw_node from lists and queue for free after
- *  rcu grace period
+ * batadv_gw_node_release() - release gw_node from lists and queue for free
+ *  after rcu grace period
  * @ref: kref pointer of the gw_node
  */
-static void batadv_gw_node_release(struct kref *ref)
+void batadv_gw_node_release(struct kref *ref)
 {
 	struct batadv_gw_node *gw_node;
 
@@ -83,14 +70,11 @@ static void batadv_gw_node_release(struct kref *ref)
 }
 
 /**
- * batadv_gw_node_put - decrement the gw_node refcounter and possibly release it
- * @gw_node: gateway node to free
+ * batadv_gw_get_selected_gw_node() - Get currently selected gateway
+ * @bat_priv: the bat priv with all the mesh interface information
+ *
+ * Return: selected gateway (with increased refcnt), NULL on errors
  */
-void batadv_gw_node_put(struct batadv_gw_node *gw_node)
-{
-	kref_put(&gw_node->refcount, batadv_gw_node_release);
-}
-
 struct batadv_gw_node *
 batadv_gw_get_selected_gw_node(struct batadv_priv *bat_priv)
 {
@@ -109,6 +93,12 @@ out:
 	return gw_node;
 }
 
+/**
+ * batadv_gw_get_selected_orig() - Get originator of currently selected gateway
+ * @bat_priv: the bat priv with all the mesh interface information
+ *
+ * Return: orig_node of selected gateway (with increased refcnt), NULL on errors
+ */
 struct batadv_orig_node *
 batadv_gw_get_selected_orig(struct batadv_priv *bat_priv)
 {
@@ -130,8 +120,7 @@ batadv_gw_get_selected_orig(struct batadv_priv *bat_priv)
 unlock:
 	rcu_read_unlock();
 out:
-	if (gw_node)
-		batadv_gw_node_put(gw_node);
+	batadv_gw_node_put(gw_node);
 	return orig_node;
 }
 
@@ -145,18 +134,17 @@ static void batadv_gw_select(struct batadv_priv *bat_priv,
 	if (new_gw_node)
 		kref_get(&new_gw_node->refcount);
 
-	curr_gw_node = rcu_dereference_protected(bat_priv->gw.curr_gw, 1);
-	rcu_assign_pointer(bat_priv->gw.curr_gw, new_gw_node);
+	curr_gw_node = rcu_replace_pointer(bat_priv->gw.curr_gw, new_gw_node,
+					   true);
 
-	if (curr_gw_node)
-		batadv_gw_node_put(curr_gw_node);
+	batadv_gw_node_put(curr_gw_node);
 
 	spin_unlock_bh(&bat_priv->gw.list_lock);
 }
 
 /**
- * batadv_gw_reselect - force a gateway reselection
- * @bat_priv: the bat priv with all the soft interface information
+ * batadv_gw_reselect() - force a gateway reselection
+ * @bat_priv: the bat priv with all the mesh interface information
  *
  * Set a flag to remind the GW component to perform a new gateway reselection.
  * However this function does not ensure that the current gateway is going to be
@@ -171,8 +159,8 @@ void batadv_gw_reselect(struct batadv_priv *bat_priv)
 }
 
 /**
- * batadv_gw_check_client_stop - check if client mode has been switched off
- * @bat_priv: the bat priv with all the soft interface information
+ * batadv_gw_check_client_stop() - check if client mode has been switched off
+ * @bat_priv: the bat priv with all the mesh interface information
  *
  * This function assumes the caller has checked that the gw state *is actually
  * changing*. This function is not supposed to be called when there is no state
@@ -202,6 +190,10 @@ void batadv_gw_check_client_stop(struct batadv_priv *bat_priv)
 	batadv_gw_node_put(curr_gw);
 }
 
+/**
+ * batadv_gw_election() - Elect the best gateway
+ * @bat_priv: the bat priv with all the mesh interface information
+ */
 void batadv_gw_election(struct batadv_priv *bat_priv)
 {
 	struct batadv_gw_node *curr_gw = NULL;
@@ -248,12 +240,12 @@ void batadv_gw_election(struct batadv_priv *bat_priv)
 		}
 	}
 
-	if ((curr_gw) && (!next_gw)) {
+	if (curr_gw && !next_gw) {
 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 			   "Removing selected gateway - no gateway in range\n");
 		batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL,
 				    NULL);
-	} else if ((!curr_gw) && (next_gw)) {
+	} else if (!curr_gw && next_gw) {
 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 			   "Adding route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
 			   next_gw->orig_node->orig,
@@ -280,16 +272,17 @@ void batadv_gw_election(struct batadv_priv *bat_priv)
 	batadv_gw_select(bat_priv, next_gw);
 
 out:
-	if (curr_gw)
-		batadv_gw_node_put(curr_gw);
-	if (next_gw)
-		batadv_gw_node_put(next_gw);
-	if (router)
-		batadv_neigh_node_put(router);
-	if (router_ifinfo)
-		batadv_neigh_ifinfo_put(router_ifinfo);
+	batadv_gw_node_put(curr_gw);
+	batadv_gw_node_put(next_gw);
+	batadv_neigh_node_put(router);
+	batadv_neigh_ifinfo_put(router_ifinfo);
 }
 
+/**
+ * batadv_gw_check_election() - Elect orig node as best gateway when eligible
+ * @bat_priv: the bat priv with all the mesh interface information
+ * @orig_node: orig node which is to be checked
+ */
 void batadv_gw_check_election(struct batadv_priv *bat_priv,
 			      struct batadv_orig_node *orig_node)
 {
@@ -316,15 +309,17 @@ void batadv_gw_check_election(struct batadv_priv *bat_priv,
 reselect:
 	batadv_gw_reselect(bat_priv);
 out:
-	if (curr_gw_orig)
-		batadv_orig_node_put(curr_gw_orig);
+	batadv_orig_node_put(curr_gw_orig);
 }
 
 /**
- * batadv_gw_node_add - add gateway node to list of available gateways
- * @bat_priv: the bat priv with all the soft interface information
+ * batadv_gw_node_add() - add gateway node to list of available gateways
+ * @bat_priv: the bat priv with all the mesh interface information
  * @orig_node: originator announcing gateway capabilities
  * @gateway: announced bandwidth information
+ *
+ * Has to be called with the appropriate locks being acquired
+ * (gw.list_lock).
  */
 static void batadv_gw_node_add(struct batadv_priv *bat_priv,
 			       struct batadv_orig_node *orig_node,
@@ -332,6 +327,8 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv,
 {
 	struct batadv_gw_node *gw_node;
 
+	lockdep_assert_held(&bat_priv->gw.list_lock);
+
 	if (gateway->bandwidth_down == 0)
 		return;
 
@@ -346,10 +343,9 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv,
 	gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
 	gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
 
-	spin_lock_bh(&bat_priv->gw.list_lock);
 	kref_get(&gw_node->refcount);
 	hlist_add_head_rcu(&gw_node->list, &bat_priv->gw.gateway_list);
-	spin_unlock_bh(&bat_priv->gw.list_lock);
+	bat_priv->gw.generation++;
 
 	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 		   "Found new gateway %pM -> gw bandwidth: %u.%u/%u.%u MBit\n",
@@ -364,8 +360,8 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv,
 }
 
 /**
- * batadv_gw_node_get - retrieve gateway node from list of available gateways
- * @bat_priv: the bat priv with all the soft interface information
+ * batadv_gw_node_get() - retrieve gateway node from list of available gateways
+ * @bat_priv: the bat priv with all the mesh interface information
  * @orig_node: originator announcing gateway capabilities
  *
  * Return: gateway node if found or NULL otherwise.
@@ -393,9 +389,9 @@ struct batadv_gw_node *batadv_gw_node_get(struct batadv_priv *bat_priv,
 }
 
 /**
- * batadv_gw_node_update - update list of available gateways with changed
+ * batadv_gw_node_update() - update list of available gateways with changed
  *  bandwidth information
- * @bat_priv: the bat priv with all the soft interface information
+ * @bat_priv: the bat priv with all the mesh interface information
  * @orig_node: originator announcing gateway capabilities
  * @gateway: announced bandwidth information
  */
@@ -405,14 +401,17 @@ void batadv_gw_node_update(struct batadv_priv *bat_priv,
 {
 	struct batadv_gw_node *gw_node, *curr_gw = NULL;
 
+	spin_lock_bh(&bat_priv->gw.list_lock);
 	gw_node = batadv_gw_node_get(bat_priv, orig_node);
 	if (!gw_node) {
 		batadv_gw_node_add(bat_priv, orig_node, gateway);
+		spin_unlock_bh(&bat_priv->gw.list_lock);
 		goto out;
 	}
+	spin_unlock_bh(&bat_priv->gw.list_lock);
 
-	if ((gw_node->bandwidth_down == ntohl(gateway->bandwidth_down)) &&
-	    (gw_node->bandwidth_up == ntohl(gateway->bandwidth_up)))
+	if (gw_node->bandwidth_down == ntohl(gateway->bandwidth_down) &&
+	    gw_node->bandwidth_up == ntohl(gateway->bandwidth_up))
 		goto out;
 
 	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
@@ -442,6 +441,7 @@ void batadv_gw_node_update(struct batadv_priv *bat_priv,
 		if (!hlist_unhashed(&gw_node->list)) {
 			hlist_del_init_rcu(&gw_node->list);
 			batadv_gw_node_put(gw_node);
+			bat_priv->gw.generation++;
 		}
 		spin_unlock_bh(&bat_priv->gw.list_lock);
 
@@ -449,15 +449,18 @@ void batadv_gw_node_update(struct batadv_priv *bat_priv,
 		if (gw_node == curr_gw)
 			batadv_gw_reselect(bat_priv);
 
-		if (curr_gw)
-			batadv_gw_node_put(curr_gw);
+		batadv_gw_node_put(curr_gw);
 	}
 
 out:
-	if (gw_node)
-		batadv_gw_node_put(gw_node);
+	batadv_gw_node_put(gw_node);
 }
 
+/**
+ * batadv_gw_node_delete() - Remove orig_node from gateway list
+ * @bat_priv: the bat priv with all the mesh interface information
+ * @orig_node: orig node which is currently in process of being removed
+ */
 void batadv_gw_node_delete(struct batadv_priv *bat_priv,
 			   struct batadv_orig_node *orig_node)
 {
@@ -469,6 +472,10 @@ void batadv_gw_node_delete(struct batadv_priv *bat_priv,
 	batadv_gw_node_update(bat_priv, orig_node, &gateway);
 }
 
+/**
+ * batadv_gw_node_free() - Free gateway information from mesh interface
+ * @bat_priv: the bat priv with all the mesh interface information
+ */
 void batadv_gw_node_free(struct batadv_priv *bat_priv)
 {
 	struct batadv_gw_node *gw_node;
@@ -479,42 +486,13 @@ void batadv_gw_node_free(struct batadv_priv *bat_priv)
 				  &bat_priv->gw.gateway_list, list) {
 		hlist_del_init_rcu(&gw_node->list);
 		batadv_gw_node_put(gw_node);
+		bat_priv->gw.generation++;
 	}
 	spin_unlock_bh(&bat_priv->gw.list_lock);
 }
 
-#ifdef CONFIG_BATMAN_ADV_DEBUGFS
-int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
-{
-	struct net_device *net_dev = (struct net_device *)seq->private;
-	struct batadv_priv *bat_priv = netdev_priv(net_dev);
-	struct batadv_hard_iface *primary_if;
-
-	primary_if = batadv_seq_print_text_primary_if_get(seq);
-	if (!primary_if)
-		return 0;
-
-	seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s %s)]\n",
-		   BATADV_SOURCE_VERSION, primary_if->net_dev->name,
-		   primary_if->net_dev->dev_addr, net_dev->name,
-		   bat_priv->algo_ops->name);
-
-	batadv_hardif_put(primary_if);
-
-	if (!bat_priv->algo_ops->gw.print) {
-		seq_puts(seq,
-			 "No printing function for this routing protocol\n");
-		return 0;
-	}
-
-	bat_priv->algo_ops->gw.print(bat_priv, seq);
-
-	return 0;
-}
-#endif
-
 /**
- * batadv_gw_dump - Dump gateways into a message
+ * batadv_gw_dump() - Dump gateways into a message
  * @msg: Netlink message to dump into
  * @cb: Control block containing additional options
  *
@@ -523,24 +501,15 @@ int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
 int batadv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
 	struct batadv_hard_iface *primary_if = NULL;
-	struct net *net = sock_net(cb->skb->sk);
-	struct net_device *soft_iface;
+	struct net_device *mesh_iface;
 	struct batadv_priv *bat_priv;
-	int ifindex;
 	int ret;
 
-	ifindex = batadv_netlink_get_ifindex(cb->nlh,
-					     BATADV_ATTR_MESH_IFINDEX);
-	if (!ifindex)
-		return -EINVAL;
-
-	soft_iface = dev_get_by_index(net, ifindex);
-	if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
-		ret = -ENODEV;
-		goto out;
-	}
+	mesh_iface = batadv_netlink_get_meshif(cb);
+	if (IS_ERR(mesh_iface))
+		return PTR_ERR(mesh_iface);
 
-	bat_priv = netdev_priv(soft_iface);
+	bat_priv = netdev_priv(mesh_iface);
 
 	primary_if = batadv_primary_if_get_selected(bat_priv);
 	if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
@@ -558,16 +527,14 @@ int batadv_gw_dump(struct sk_buff *msg, struct netlink_callback *cb)
 	ret = msg->len;
 
 out:
-	if (primary_if)
-		batadv_hardif_put(primary_if);
-	if (soft_iface)
-		dev_put(soft_iface);
+	batadv_hardif_put(primary_if);
+	dev_put(mesh_iface);
 
 	return ret;
 }
 
 /**
- * batadv_gw_dhcp_recipient_get - check if a packet is a DHCP message
+ * batadv_gw_dhcp_recipient_get() - check if a packet is a DHCP message
  * @skb: the packet to check
  * @header_len: a pointer to the batman-adv header size
  * @chaddr: buffer where the client address will be stored. Valid
@@ -667,8 +634,10 @@ batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len,
 
 	chaddr_offset = *header_len + BATADV_DHCP_CHADDR_OFFSET;
 	/* store the client address if the message is going to a client */
-	if (ret == BATADV_DHCP_TO_CLIENT &&
-	    pskb_may_pull(skb, chaddr_offset + ETH_ALEN)) {
+	if (ret == BATADV_DHCP_TO_CLIENT) {
+		if (!pskb_may_pull(skb, chaddr_offset + ETH_ALEN))
+			return BATADV_DHCP_NO;
+
 		/* check if the DHCP packet carries an Ethernet DHCP */
 		p = skb->data + *header_len + BATADV_DHCP_HTYPE_OFFSET;
 		if (*p != BATADV_DHCP_HTYPE_ETHERNET)
@@ -686,8 +655,9 @@ batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len,
 }
 
 /**
- * batadv_gw_out_of_range - check if the dhcp request destination is the best gw
- * @bat_priv: the bat priv with all the soft interface information
+ * batadv_gw_out_of_range() - check if the dhcp request destination is the best
+ *  gateway
+ * @bat_priv: the bat priv with all the mesh interface information
  * @skb: the outgoing packet
  *
  * Check if the skb is a DHCP request and if it is sent to the current best GW
@@ -705,7 +675,7 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
 {
 	struct batadv_neigh_node *neigh_curr = NULL;
 	struct batadv_neigh_node *neigh_old = NULL;
-	struct batadv_orig_node *orig_dst_node;
+	struct batadv_orig_node *orig_dst_node = NULL;
 	struct batadv_gw_node *gw_node = NULL;
 	struct batadv_gw_node *curr_gw = NULL;
 	struct batadv_neigh_ifinfo *curr_ifinfo, *old_ifinfo;
@@ -716,6 +686,9 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
 
 	vid = batadv_get_vid(skb, 0);
 
+	if (is_multicast_ether_addr(ethhdr->h_dest))
+		goto out;
+
 	orig_dst_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
 						 ethhdr->h_dest, vid);
 	if (!orig_dst_node)
@@ -777,15 +750,10 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
 	batadv_neigh_ifinfo_put(old_ifinfo);
 
 out:
-	if (orig_dst_node)
-		batadv_orig_node_put(orig_dst_node);
-	if (curr_gw)
-		batadv_gw_node_put(curr_gw);
-	if (gw_node)
-		batadv_gw_node_put(gw_node);
-	if (neigh_old)
-		batadv_neigh_node_put(neigh_old);
-	if (neigh_curr)
-		batadv_neigh_node_put(neigh_curr);
+	batadv_orig_node_put(orig_dst_node);
+	batadv_gw_node_put(curr_gw);
+	batadv_gw_node_put(gw_node);
+	batadv_neigh_node_put(neigh_old);
+	batadv_neigh_node_put(neigh_curr);
 	return out_of_range;
 }