1 files changed, 123 insertions, 111 deletions

diff --git a/net/batman-adv/send.c b/net/batman-adv/send.c
index f2f125684ed9..8d4e1f578574 100644
--- a/net/batman-adv/send.c
+++ b/net/batman-adv/send.c
@@ -20,10 +20,11 @@
 
 #include <linux/atomic.h>
 #include <linux/byteorder/generic.h>
+#include <linux/errno.h>
 #include <linux/etherdevice.h>
 #include <linux/fs.h>
-#include <linux/if_ether.h>
 #include <linux/if.h>
+#include <linux/if_ether.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
 #include <linux/kref.h>
@@ -42,6 +43,7 @@
 #include "fragmentation.h"
 #include "gateway_client.h"
 #include "hard-interface.h"
+#include "log.h"
 #include "network-coding.h"
 #include "originator.h"
 #include "routing.h"
@@ -71,6 +73,7 @@ int batadv_send_skb_packet(struct sk_buff *skb,
 {
 	struct batadv_priv *bat_priv;
 	struct ethhdr *ethhdr;
+	int ret;
 
 	bat_priv = netdev_priv(hard_iface->soft_iface);
 
@@ -108,8 +111,15 @@ int batadv_send_skb_packet(struct sk_buff *skb,
 	/* dev_queue_xmit() returns a negative result on error.	 However on
 	 * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
 	 * (which is > 0). This will not be treated as an error.
+	 *
+	 * a negative value cannot be returned because it could be interepreted
+	 * as not consumed skb by callers of batadv_send_skb_to_orig.
 	 */
-	return dev_queue_xmit(skb);
+	ret = dev_queue_xmit(skb);
+	if (ret < 0)
+		ret = NET_XMIT_DROP;
+
+	return ret;
 send_skb_err:
 	kfree_skb(skb);
 	return NET_XMIT_DROP;
@@ -155,8 +165,11 @@ int batadv_send_unicast_skb(struct sk_buff *skb,
  * host, NULL can be passed as recv_if and no interface alternating is
  * attempted.
  *
- * Return: NET_XMIT_SUCCESS on success, NET_XMIT_DROP on failure, or
- * NET_XMIT_POLICED if the skb is buffered for later transmit.
+ * Return: -1 on failure (and the skb is not consumed), -EINPROGRESS if the
+ * skb is buffered for later transmit or the NET_XMIT status returned by the
+ * lower routine if the packet has been passed down.
+ *
+ * If the returning value is not -1 the skb has been consumed.
  */
 int batadv_send_skb_to_orig(struct sk_buff *skb,
 			    struct batadv_orig_node *orig_node,
@@ -164,7 +177,7 @@ int batadv_send_skb_to_orig(struct sk_buff *skb,
 {
 	struct batadv_priv *bat_priv = orig_node->bat_priv;
 	struct batadv_neigh_node *neigh_node;
-	int ret = NET_XMIT_DROP;
+	int ret = -1;
 
 	/* batadv_find_router() increases neigh_nodes refcount if found. */
 	neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
@@ -177,8 +190,7 @@ int batadv_send_skb_to_orig(struct sk_buff *skb,
 	if (atomic_read(&bat_priv->fragmentation) &&
 	    skb->len > neigh_node->if_incoming->net_dev->mtu) {
 		/* Fragment and send packet. */
-		if (batadv_frag_send_packet(skb, orig_node, neigh_node))
-			ret = NET_XMIT_SUCCESS;
+		ret = batadv_frag_send_packet(skb, orig_node, neigh_node);
 
 		goto out;
 	}
@@ -187,12 +199,10 @@ int batadv_send_skb_to_orig(struct sk_buff *skb,
 	 * (i.e. being forwarded). If the packet originates from this node or if
 	 * network coding fails, then send the packet as usual.
 	 */
-	if (recv_if && batadv_nc_skb_forward(skb, neigh_node)) {
-		ret = NET_XMIT_POLICED;
-	} else {
-		batadv_send_unicast_skb(skb, neigh_node);
-		ret = NET_XMIT_SUCCESS;
-	}
+	if (recv_if && batadv_nc_skb_forward(skb, neigh_node))
+		ret = -EINPROGRESS;
+	else
+		ret = batadv_send_unicast_skb(skb, neigh_node);
 
 out:
 	if (neigh_node)
@@ -305,8 +315,7 @@ out:
  *
  * Wrap the given skb into a batman-adv unicast or unicast-4addr header
  * depending on whether BATADV_UNICAST or BATADV_UNICAST_4ADDR was supplied
- * as packet_type. Then send this frame to the given orig_node and release a
- * reference to this orig_node.
+ * as packet_type. Then send this frame to the given orig_node.
  *
  * Return: NET_XMIT_DROP in case of error or NET_XMIT_SUCCESS otherwise.
  */
@@ -318,7 +327,7 @@ int batadv_send_skb_unicast(struct batadv_priv *bat_priv,
 {
 	struct batadv_unicast_packet *unicast_packet;
 	struct ethhdr *ethhdr;
-	int ret = NET_XMIT_DROP;
+	int res, ret = NET_XMIT_DROP;
 
 	if (!orig_node)
 		goto out;
@@ -355,12 +364,11 @@ int batadv_send_skb_unicast(struct batadv_priv *bat_priv,
 	if (batadv_tt_global_client_is_roaming(bat_priv, ethhdr->h_dest, vid))
 		unicast_packet->ttvn = unicast_packet->ttvn - 1;
 
-	if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
+	res = batadv_send_skb_to_orig(skb, orig_node, NULL);
+	if (res != -1)
 		ret = NET_XMIT_SUCCESS;
 
 out:
-	if (orig_node)
-		batadv_orig_node_put(orig_node);
 	if (ret == NET_XMIT_DROP)
 		kfree_skb(skb);
 	return ret;
@@ -392,6 +400,7 @@ int batadv_send_skb_via_tt_generic(struct batadv_priv *bat_priv,
 	struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
 	struct batadv_orig_node *orig_node;
 	u8 *src, *dst;
+	int ret;
 
 	src = ethhdr->h_source;
 	dst = ethhdr->h_dest;
@@ -403,8 +412,13 @@ int batadv_send_skb_via_tt_generic(struct batadv_priv *bat_priv,
 	}
 	orig_node = batadv_transtable_search(bat_priv, src, dst, vid);
 
-	return batadv_send_skb_unicast(bat_priv, skb, packet_type,
-				       packet_subtype, orig_node, vid);
+	ret = batadv_send_skb_unicast(bat_priv, skb, packet_type,
+				      packet_subtype, orig_node, vid);
+
+	if (orig_node)
+		batadv_orig_node_put(orig_node);
+
+	return ret;
 }
 
 /**
@@ -422,42 +436,99 @@ int batadv_send_skb_via_gw(struct batadv_priv *bat_priv, struct sk_buff *skb,
 			   unsigned short vid)
 {
 	struct batadv_orig_node *orig_node;
+	int ret;
 
 	orig_node = batadv_gw_get_selected_orig(bat_priv);
-	return batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST, 0,
-				       orig_node, vid);
-}
-
-void batadv_schedule_bat_ogm(struct batadv_hard_iface *hard_iface)
-{
-	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
-
-	if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) ||
-	    (hard_iface->if_status == BATADV_IF_TO_BE_REMOVED))
-		return;
+	ret = batadv_send_skb_unicast(bat_priv, skb, BATADV_UNICAST_4ADDR,
+				      BATADV_P_DATA, orig_node, vid);
 
-	/* the interface gets activated here to avoid race conditions between
-	 * the moment of activating the interface in
-	 * hardif_activate_interface() where the originator mac is set and
-	 * outdated packets (especially uninitialized mac addresses) in the
-	 * packet queue
-	 */
-	if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
-		hard_iface->if_status = BATADV_IF_ACTIVE;
+	if (orig_node)
+		batadv_orig_node_put(orig_node);
 
-	bat_priv->bat_algo_ops->bat_ogm_schedule(hard_iface);
+	return ret;
 }
 
-static void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet)
+/**
+ * batadv_forw_packet_free - free a forwarding packet
+ * @forw_packet: The packet to free
+ *
+ * This frees a forwarding packet and releases any resources it might
+ * have claimed.
+ */
+void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet)
 {
 	kfree_skb(forw_packet->skb);
 	if (forw_packet->if_incoming)
 		batadv_hardif_put(forw_packet->if_incoming);
 	if (forw_packet->if_outgoing)
 		batadv_hardif_put(forw_packet->if_outgoing);
+	if (forw_packet->queue_left)
+		atomic_inc(forw_packet->queue_left);
 	kfree(forw_packet);
 }
 
+/**
+ * batadv_forw_packet_alloc - allocate a forwarding packet
+ * @if_incoming: The (optional) if_incoming to be grabbed
+ * @if_outgoing: The (optional) if_outgoing to be grabbed
+ * @queue_left: The (optional) queue counter to decrease
+ * @bat_priv: The bat_priv for the mesh of this forw_packet
+ *
+ * Allocates a forwarding packet and tries to get a reference to the
+ * (optional) if_incoming, if_outgoing and queue_left. If queue_left
+ * is NULL then bat_priv is optional, too.
+ *
+ * Return: An allocated forwarding packet on success, NULL otherwise.
+ */
+struct batadv_forw_packet *
+batadv_forw_packet_alloc(struct batadv_hard_iface *if_incoming,
+			 struct batadv_hard_iface *if_outgoing,
+			 atomic_t *queue_left,
+			 struct batadv_priv *bat_priv)
+{
+	struct batadv_forw_packet *forw_packet;
+	const char *qname;
+
+	if (queue_left && !batadv_atomic_dec_not_zero(queue_left)) {
+		qname = "unknown";
+
+		if (queue_left == &bat_priv->bcast_queue_left)
+			qname = "bcast";
+
+		if (queue_left == &bat_priv->batman_queue_left)
+			qname = "batman";
+
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "%s queue is full\n", qname);
+
+		return NULL;
+	}
+
+	forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC);
+	if (!forw_packet)
+		goto err;
+
+	if (if_incoming)
+		kref_get(&if_incoming->refcount);
+
+	if (if_outgoing)
+		kref_get(&if_outgoing->refcount);
+
+	forw_packet->skb = NULL;
+	forw_packet->queue_left = queue_left;
+	forw_packet->if_incoming = if_incoming;
+	forw_packet->if_outgoing = if_outgoing;
+	forw_packet->num_packets = 0;
+
+	return forw_packet;
+
+err:
+	if (queue_left)
+		atomic_inc(queue_left);
+
+	return NULL;
+}
+
 static void
 _batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 				 struct batadv_forw_packet *forw_packet,
@@ -496,24 +567,20 @@ int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 	struct batadv_bcast_packet *bcast_packet;
 	struct sk_buff *newskb;
 
-	if (!batadv_atomic_dec_not_zero(&bat_priv->bcast_queue_left)) {
-		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-			   "bcast packet queue full\n");
-		goto out;
-	}
-
 	primary_if = batadv_primary_if_get_selected(bat_priv);
 	if (!primary_if)
-		goto out_and_inc;
-
-	forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC);
+		goto err;
 
+	forw_packet = batadv_forw_packet_alloc(primary_if, NULL,
+					       &bat_priv->bcast_queue_left,
+					       bat_priv);
+	batadv_hardif_put(primary_if);
 	if (!forw_packet)
-		goto out_and_inc;
+		goto err;
 
 	newskb = skb_copy(skb, GFP_ATOMIC);
 	if (!newskb)
-		goto packet_free;
+		goto err_packet_free;
 
 	/* as we have a copy now, it is safe to decrease the TTL */
 	bcast_packet = (struct batadv_bcast_packet *)newskb->data;
@@ -522,11 +589,6 @@ int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 	skb_reset_mac_header(newskb);
 
 	forw_packet->skb = newskb;
-	forw_packet->if_incoming = primary_if;
-	forw_packet->if_outgoing = NULL;
-
-	/* how often did we send the bcast packet ? */
-	forw_packet->num_packets = 0;
 
 	INIT_DELAYED_WORK(&forw_packet->delayed_work,
 			  batadv_send_outstanding_bcast_packet);
@@ -534,13 +596,9 @@ int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 	_batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay);
 	return NETDEV_TX_OK;
 
-packet_free:
-	kfree(forw_packet);
-out_and_inc:
-	atomic_inc(&bat_priv->bcast_queue_left);
-out:
-	if (primary_if)
-		batadv_hardif_put(primary_if);
+err_packet_free:
+	batadv_forw_packet_free(forw_packet);
+err:
 	return NETDEV_TX_BUSY;
 }
 
@@ -601,46 +659,6 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
 
 out:
 	batadv_forw_packet_free(forw_packet);
-	atomic_inc(&bat_priv->bcast_queue_left);
-}
-
-void batadv_send_outstanding_bat_ogm_packet(struct work_struct *work)
-{
-	struct delayed_work *delayed_work;
-	struct batadv_forw_packet *forw_packet;
-	struct batadv_priv *bat_priv;
-
-	delayed_work = to_delayed_work(work);
-	forw_packet = container_of(delayed_work, struct batadv_forw_packet,
-				   delayed_work);
-	bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
-	spin_lock_bh(&bat_priv->forw_bat_list_lock);
-	hlist_del(&forw_packet->list);
-	spin_unlock_bh(&bat_priv->forw_bat_list_lock);
-
-	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
-		goto out;
-
-	bat_priv->bat_algo_ops->bat_ogm_emit(forw_packet);
-
-	/* we have to have at least one packet in the queue to determine the
-	 * queues wake up time unless we are shutting down.
-	 *
-	 * only re-schedule if this is the "original" copy, e.g. the OGM of the
-	 * primary interface should only be rescheduled once per period, but
-	 * this function will be called for the forw_packet instances of the
-	 * other secondary interfaces as well.
-	 */
-	if (forw_packet->own &&
-	    forw_packet->if_incoming == forw_packet->if_outgoing)
-		batadv_schedule_bat_ogm(forw_packet->if_incoming);
-
-out:
-	/* don't count own packet */
-	if (!forw_packet->own)
-		atomic_inc(&bat_priv->batman_queue_left);
-
-	batadv_forw_packet_free(forw_packet);
 }
 
 void
@@ -681,9 +699,6 @@ batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
 
 		if (pending) {
 			hlist_del(&forw_packet->list);
-			if (!forw_packet->own)
-				atomic_inc(&bat_priv->bcast_queue_left);
-
 			batadv_forw_packet_free(forw_packet);
 		}
 	}
@@ -711,9 +726,6 @@ batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
 
 		if (pending) {
 			hlist_del(&forw_packet->list);
-			if (!forw_packet->own)
-				atomic_inc(&bat_priv->batman_queue_left);
-
 			batadv_forw_packet_free(forw_packet);
 		}
 	}