Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ba85fac2 authored by Simon Wunderlich's avatar Simon Wunderlich Committed by Sven Eckelmann
Browse files

batman-adv: protect softif_neigh by rcu 



Add get/set wrapper functions for softif_neigh and
use rcu functions to manipulate the pointers.

Signed-off-by: default avatarSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: default avatarMarek Lindner <lindner_marek@yahoo.de>
Signed-off-by: default avatarSven Eckelmann <sven@narfation.org>
parent c4aac1ab

net/batman-adv/soft-interface.c

+87 −27
Original line number Original line Diff line number Diff line
@@ -90,10 +90,51 @@ static void softif_neigh_free_ref(struct softif_neigh *softif_neigh) 
		call_rcu(&softif_neigh->rcu, softif_neigh_free_rcu);

		call_rcu(&softif_neigh->rcu, softif_neigh_free_rcu);

}

}





static struct softif_neigh *softif_neigh_get_selected(struct bat_priv *bat_priv)

{

	struct softif_neigh *neigh;



	rcu_read_lock();

	neigh = rcu_dereference(bat_priv->softif_neigh);



	if (neigh && !atomic_inc_not_zero(&neigh->refcount))

		neigh = NULL;



	rcu_read_unlock();

	return neigh;

}



static void softif_neigh_select(struct bat_priv *bat_priv,

				struct softif_neigh *new_neigh)

{

	struct softif_neigh *curr_neigh;



	spin_lock_bh(&bat_priv->softif_neigh_lock);



	if (new_neigh && !atomic_inc_not_zero(&new_neigh->refcount))

		new_neigh = NULL;



	curr_neigh = bat_priv->softif_neigh;

	rcu_assign_pointer(bat_priv->softif_neigh, new_neigh);



	if (curr_neigh)

		softif_neigh_free_ref(curr_neigh);



	spin_unlock_bh(&bat_priv->softif_neigh_lock);

}



static void softif_neigh_deselect(struct bat_priv *bat_priv)

{

	softif_neigh_select(bat_priv, NULL);

}



void softif_neigh_purge(struct bat_priv *bat_priv)

void softif_neigh_purge(struct bat_priv *bat_priv)

{

{

	struct softif_neigh *softif_neigh, *softif_neigh_tmp;

	struct softif_neigh *softif_neigh, *curr_softif_neigh;

	struct hlist_node *node, *node_tmp;

	struct hlist_node *node, *node_tmp;

	char do_deselect = 0;



	curr_softif_neigh = softif_neigh_get_selected(bat_priv);





	spin_lock_bh(&bat_priv->softif_neigh_lock);

	spin_lock_bh(&bat_priv->softif_neigh_lock);
@@ -105,22 +146,26 @@ void softif_neigh_purge(struct bat_priv *bat_priv) 
		    (atomic_read(&bat_priv->mesh_state) == MESH_ACTIVE))

		    (atomic_read(&bat_priv->mesh_state) == MESH_ACTIVE))

			continue;

			continue;





		hlist_del_rcu(&softif_neigh->list);

		if (curr_softif_neigh == softif_neigh) {



		if (bat_priv->softif_neigh == softif_neigh) {

			bat_dbg(DBG_ROUTES, bat_priv,

			bat_dbg(DBG_ROUTES, bat_priv,

				 "Current mesh exit point '%pM' vanished "

				 "Current mesh exit point '%pM' vanished "

				 "(vid: %d).\n",

				 "(vid: %d).\n",

				 softif_neigh->addr, softif_neigh->vid);

				 softif_neigh->addr, softif_neigh->vid);

			softif_neigh_tmp = bat_priv->softif_neigh;

			do_deselect = 1;

			bat_priv->softif_neigh = NULL;

			softif_neigh_free_ref(softif_neigh_tmp);

		}

		}





		hlist_del_rcu(&softif_neigh->list);

		softif_neigh_free_ref(softif_neigh);

		softif_neigh_free_ref(softif_neigh);

	}

	}





	spin_unlock_bh(&bat_priv->softif_neigh_lock);

	spin_unlock_bh(&bat_priv->softif_neigh_lock);



	/* soft_neigh_deselect() needs to acquire the softif_neigh_lock */

	if (do_deselect)

		softif_neigh_deselect(bat_priv);



	if (curr_softif_neigh)

		softif_neigh_free_ref(curr_softif_neigh);

}

}





static struct softif_neigh *softif_neigh_get(struct bat_priv *bat_priv,

static struct softif_neigh *softif_neigh_get(struct bat_priv *bat_priv,
@@ -171,6 +216,7 @@ int softif_neigh_seq_print_text(struct seq_file *seq, void *offset) 
	struct bat_priv *bat_priv = netdev_priv(net_dev);

	struct bat_priv *bat_priv = netdev_priv(net_dev);

	struct softif_neigh *softif_neigh;

	struct softif_neigh *softif_neigh;

	struct hlist_node *node;

	struct hlist_node *node;

	struct softif_neigh *curr_softif_neigh;





	if (!bat_priv->primary_if) {

	if (!bat_priv->primary_if) {

		return seq_printf(seq, "BATMAN mesh %s disabled - "

		return seq_printf(seq, "BATMAN mesh %s disabled - "
@@ -180,14 +226,17 @@ int softif_neigh_seq_print_text(struct seq_file *seq, void *offset) 




	seq_printf(seq, "Softif neighbor list (%s)\n", net_dev->name);

	seq_printf(seq, "Softif neighbor list (%s)\n", net_dev->name);





	curr_softif_neigh = softif_neigh_get_selected(bat_priv);

	rcu_read_lock();

	rcu_read_lock();

	hlist_for_each_entry_rcu(softif_neigh, node,

	hlist_for_each_entry_rcu(softif_neigh, node,

				 &bat_priv->softif_neigh_list, list)

				 &bat_priv->softif_neigh_list, list)

		seq_printf(seq, "%s %pM (vid: %d)\n",

		seq_printf(seq, "%s %pM (vid: %d)\n",

				bat_priv->softif_neigh == softif_neigh

				curr_softif_neigh == softif_neigh

				? "=>" : "  ", softif_neigh->addr,

				? "=>" : "  ", softif_neigh->addr,

				softif_neigh->vid);

				softif_neigh->vid);

	rcu_read_unlock();

	rcu_read_unlock();

	if (curr_softif_neigh)

		softif_neigh_free_ref(curr_softif_neigh);





	return 0;

	return 0;

}

}
@@ -198,7 +247,8 @@ static void softif_batman_recv(struct sk_buff *skb, struct net_device *dev, 
	struct bat_priv *bat_priv = netdev_priv(dev);

	struct bat_priv *bat_priv = netdev_priv(dev);

	struct ethhdr *ethhdr = (struct ethhdr *)skb->data;

	struct ethhdr *ethhdr = (struct ethhdr *)skb->data;

	struct batman_packet *batman_packet;

	struct batman_packet *batman_packet;

	struct softif_neigh *softif_neigh, *softif_neigh_tmp;

	struct softif_neigh *softif_neigh;

	struct softif_neigh *curr_softif_neigh = NULL;





	if (ntohs(ethhdr->h_proto) == ETH_P_8021Q)

	if (ntohs(ethhdr->h_proto) == ETH_P_8021Q)

		batman_packet = (struct batman_packet *)

		batman_packet = (struct batman_packet *)
@@ -223,7 +273,8 @@ static void softif_batman_recv(struct sk_buff *skb, struct net_device *dev, 
	if (!softif_neigh)

	if (!softif_neigh)

		goto err;

		goto err;





	if (bat_priv->softif_neigh == softif_neigh)

	curr_softif_neigh = softif_neigh_get_selected(bat_priv);

	if (curr_softif_neigh == softif_neigh)

		goto out;

		goto out;





	/* we got a neighbor but its mac is 'bigger' than ours  */

	/* we got a neighbor but its mac is 'bigger' than ours  */
@@ -232,38 +283,39 @@ static void softif_batman_recv(struct sk_buff *skb, struct net_device *dev, 
		goto out;

		goto out;





	/* switch to new 'smallest neighbor' */

	/* switch to new 'smallest neighbor' */

	if ((bat_priv->softif_neigh) &&

	if ((curr_softif_neigh) &&

	    (memcmp(softif_neigh->addr, bat_priv->softif_neigh->addr,

	    (memcmp(softif_neigh->addr, curr_softif_neigh->addr,

							ETH_ALEN) < 0)) {

							ETH_ALEN) < 0)) {

		bat_dbg(DBG_ROUTES, bat_priv,

		bat_dbg(DBG_ROUTES, bat_priv,

			"Changing mesh exit point from %pM (vid: %d) "

			"Changing mesh exit point from %pM (vid: %d) "

			"to %pM (vid: %d).\n",

			"to %pM (vid: %d).\n",

			 bat_priv->softif_neigh->addr,

			 curr_softif_neigh->addr,

			 bat_priv->softif_neigh->vid,

			 curr_softif_neigh->vid,

			 softif_neigh->addr, softif_neigh->vid);

			 softif_neigh->addr, softif_neigh->vid);

		softif_neigh_tmp = bat_priv->softif_neigh;



		bat_priv->softif_neigh = softif_neigh;

		softif_neigh_select(bat_priv, softif_neigh);

		softif_neigh_free_ref(softif_neigh_tmp);

		goto out;

		/* we need to hold the additional reference */

		goto err;

	}

	}





	/* close own batX device and use softif_neigh as exit node */

	/* close own batX device and use softif_neigh as exit node */

	if ((!bat_priv->softif_neigh) &&

	if ((!curr_softif_neigh) &&

	    (memcmp(softif_neigh->addr,

	    (memcmp(softif_neigh->addr,

		    bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN) < 0)) {

		    bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN) < 0)) {

		bat_dbg(DBG_ROUTES, bat_priv,

		bat_dbg(DBG_ROUTES, bat_priv,

			"Setting mesh exit point to %pM (vid: %d).\n",

			"Setting mesh exit point to %pM (vid: %d).\n",

			softif_neigh->addr, softif_neigh->vid);

			softif_neigh->addr, softif_neigh->vid);

		bat_priv->softif_neigh = softif_neigh;



		/* we need to hold the additional reference */

		softif_neigh_select(bat_priv, softif_neigh);

		goto err;

		goto out;

	}

	}





out:

out:

	softif_neigh_free_ref(softif_neigh);

	softif_neigh_free_ref(softif_neigh);

err:

err:

	kfree_skb(skb);

	kfree_skb(skb);

	if (curr_softif_neigh)

		softif_neigh_free_ref(curr_softif_neigh);



	return;

	return;

}

}
@@ -321,6 +373,7 @@ int interface_tx(struct sk_buff *skb, struct net_device *soft_iface) 
	struct bat_priv *bat_priv = netdev_priv(soft_iface);

	struct bat_priv *bat_priv = netdev_priv(soft_iface);

	struct bcast_packet *bcast_packet;

	struct bcast_packet *bcast_packet;

	struct vlan_ethhdr *vhdr;

	struct vlan_ethhdr *vhdr;

	struct softif_neigh *curr_softif_neigh = NULL;

	int data_len = skb->len, ret;

	int data_len = skb->len, ret;

	short vid = -1;

	short vid = -1;

	bool do_bcast = false;

	bool do_bcast = false;
@@ -348,7 +401,8 @@ int interface_tx(struct sk_buff *skb, struct net_device *soft_iface) 
	 * if we have a another chosen mesh exit node in range

	 * if we have a another chosen mesh exit node in range

	 * it will transport the packets to the mesh

	 * it will transport the packets to the mesh

	 */

	 */

	if ((bat_priv->softif_neigh) && (bat_priv->softif_neigh->vid == vid))

	curr_softif_neigh = softif_neigh_get_selected(bat_priv);

	if ((curr_softif_neigh) && (curr_softif_neigh->vid == vid))

		goto dropped;

		goto dropped;





	/* TODO: check this for locks */

	/* TODO: check this for locks */
@@ -410,6 +464,8 @@ dropped: 
dropped_freed:

dropped_freed:

	bat_priv->stats.tx_dropped++;

	bat_priv->stats.tx_dropped++;

end:

end:

	if (curr_softif_neigh)

		softif_neigh_free_ref(curr_softif_neigh);

	return NETDEV_TX_OK;

	return NETDEV_TX_OK;

}

}
@@ -421,6 +477,7 @@ void interface_rx(struct net_device *soft_iface, 
	struct unicast_packet *unicast_packet;

	struct unicast_packet *unicast_packet;

	struct ethhdr *ethhdr;

	struct ethhdr *ethhdr;

	struct vlan_ethhdr *vhdr;

	struct vlan_ethhdr *vhdr;

	struct softif_neigh *curr_softif_neigh = NULL;

	short vid = -1;

	short vid = -1;

	int ret;

	int ret;
@@ -450,7 +507,8 @@ void interface_rx(struct net_device *soft_iface, 
	 * if we have a another chosen mesh exit node in range

	 * if we have a another chosen mesh exit node in range

	 * it will transport the packets to the non-mesh network

	 * it will transport the packets to the non-mesh network

	 */

	 */

	if ((bat_priv->softif_neigh) && (bat_priv->softif_neigh->vid == vid)) {

	curr_softif_neigh = softif_neigh_get_selected(bat_priv);

	if (curr_softif_neigh && (curr_softif_neigh->vid == vid)) {

		skb_push(skb, hdr_size);

		skb_push(skb, hdr_size);

		unicast_packet = (struct unicast_packet *)skb->data;

		unicast_packet = (struct unicast_packet *)skb->data;
@@ -461,7 +519,7 @@ void interface_rx(struct net_device *soft_iface, 
		skb_reset_mac_header(skb);

		skb_reset_mac_header(skb);





		memcpy(unicast_packet->dest,

		memcpy(unicast_packet->dest,

		       bat_priv->softif_neigh->addr, ETH_ALEN);

		       curr_softif_neigh->addr, ETH_ALEN);

		ret = route_unicast_packet(skb, recv_if);

		ret = route_unicast_packet(skb, recv_if);

		if (ret == NET_RX_DROP)

		if (ret == NET_RX_DROP)

			goto dropped;

			goto dropped;
@@ -486,11 +544,13 @@ void interface_rx(struct net_device *soft_iface, 
	soft_iface->last_rx = jiffies;

	soft_iface->last_rx = jiffies;





	netif_rx(skb);

	netif_rx(skb);

	return;

	goto out;





dropped:

dropped:

	kfree_skb(skb);

	kfree_skb(skb);

out:

out:

	if (curr_softif_neigh)

		softif_neigh_free_ref(curr_softif_neigh);

	return;

	return;

}

}

net/batman-adv/types.h

+1 −1
Original line number Original line Diff line number Diff line
@@ -147,7 +147,7 @@ struct bat_priv { 
	atomic_t batman_queue_left;

	atomic_t batman_queue_left;

	char num_ifaces;

	char num_ifaces;

	struct hlist_head softif_neigh_list;

	struct hlist_head softif_neigh_list;

	struct softif_neigh *softif_neigh;

	struct softif_neigh __rcu *softif_neigh;

	struct debug_log *debug_log;

	struct debug_log *debug_log;

	struct hard_iface *primary_if;

	struct hard_iface *primary_if;

	struct kobject *mesh_obj;

	struct kobject *mesh_obj;