1 files changed, 111 insertions, 108 deletions

diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c
index d9bcbe6e7d65..473ebb9a0e73 100644
--- a/net/batman-adv/bat_v_ogm.c
+++ b/net/batman-adv/bat_v_ogm.c
@@ -26,6 +26,7 @@
 #include <linux/if_ether.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
+#include <linux/kref.h>
 #include <linux/list.h>
 #include <linux/netdevice.h>
 #include <linux/random.h>
@@ -176,6 +177,9 @@ static void batadv_v_ogm_send(struct work_struct *work)
 		if (hard_iface->soft_iface != bat_priv->soft_iface)
 			continue;
 
+		if (!kref_get_unless_zero(&hard_iface->refcount))
+			continue;
+
 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 			   "Sending own OGM2 packet (originator %pM, seqno %u, throughput %u, TTL %d) on interface %s [%pM]\n",
 			   ogm_packet->orig, ntohl(ogm_packet->seqno),
@@ -185,10 +189,13 @@ static void batadv_v_ogm_send(struct work_struct *work)
 
 		/* this skb gets consumed by batadv_v_ogm_send_to_if() */
 		skb_tmp = skb_clone(skb, GFP_ATOMIC);
-		if (!skb_tmp)
+		if (!skb_tmp) {
+			batadv_hardif_put(hard_iface);
 			break;
+		}
 
 		batadv_v_ogm_send_to_if(skb_tmp, hard_iface);
+		batadv_hardif_put(hard_iface);
 	}
 	rcu_read_unlock();
 
@@ -234,73 +241,6 @@ void batadv_v_ogm_primary_iface_set(struct batadv_hard_iface *primary_iface)
 }
 
 /**
- * batadv_v_ogm_orig_update - update the originator status based on the received
- *  OGM
- * @bat_priv: the bat priv with all the soft interface information
- * @orig_node: the originator to update
- * @neigh_node: the neighbour the OGM has been received from (to update)
- * @ogm2: the received OGM
- * @if_outgoing: the interface where this OGM is going to be forwarded through
- */
-static void
-batadv_v_ogm_orig_update(struct batadv_priv *bat_priv,
-			 struct batadv_orig_node *orig_node,
-			 struct batadv_neigh_node *neigh_node,
-			 const struct batadv_ogm2_packet *ogm2,
-			 struct batadv_hard_iface *if_outgoing)
-{
-	struct batadv_neigh_ifinfo *router_ifinfo = NULL, *neigh_ifinfo = NULL;
-	struct batadv_neigh_node *router = NULL;
-	s32 neigh_seq_diff;
-	u32 neigh_last_seqno;
-	u32 router_last_seqno;
-	u32 router_throughput, neigh_throughput;
-
-	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-		   "Searching and updating originator entry of received packet\n");
-
-	/* if this neighbor already is our next hop there is nothing
-	 * to change
-	 */
-	router = batadv_orig_router_get(orig_node, if_outgoing);
-	if (router == neigh_node)
-		goto out;
-
-	/* don't consider neighbours with worse throughput.
-	 * also switch route if this seqno is BATADV_V_MAX_ORIGDIFF newer than
-	 * the last received seqno from our best next hop.
-	 */
-	if (router) {
-		router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
-		neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
-
-		/* if these are not allocated, something is wrong. */
-		if (!router_ifinfo || !neigh_ifinfo)
-			goto out;
-
-		neigh_last_seqno = neigh_ifinfo->bat_v.last_seqno;
-		router_last_seqno = router_ifinfo->bat_v.last_seqno;
-		neigh_seq_diff = neigh_last_seqno - router_last_seqno;
-		router_throughput = router_ifinfo->bat_v.throughput;
-		neigh_throughput = neigh_ifinfo->bat_v.throughput;
-
-		if ((neigh_seq_diff < BATADV_OGM_MAX_ORIGDIFF) &&
-		    (router_throughput >= neigh_throughput))
-			goto out;
-	}
-
-	batadv_update_route(bat_priv, orig_node, if_outgoing, neigh_node);
-
-out:
-	if (router_ifinfo)
-		batadv_neigh_ifinfo_put(router_ifinfo);
-	if (neigh_ifinfo)
-		batadv_neigh_ifinfo_put(neigh_ifinfo);
-	if (router)
-		batadv_neigh_node_put(router);
-}
-
-/**
  * batadv_v_forward_penalty - apply a penalty to the throughput metric forwarded
  *  with B.A.T.M.A.N. V OGMs
  * @bat_priv: the bat priv with all the soft interface information
@@ -347,10 +287,12 @@ static u32 batadv_v_forward_penalty(struct batadv_priv *bat_priv,
 }
 
 /**
- * batadv_v_ogm_forward - forward an OGM to the given outgoing interface
+ * batadv_v_ogm_forward - check conditions and forward an OGM to the given
+ *  outgoing interface
  * @bat_priv: the bat priv with all the soft interface information
  * @ogm_received: previously received OGM to be forwarded
- * @throughput: throughput to announce, may vary per outgoing interface
+ * @orig_node: the originator which has been updated
+ * @neigh_node: the neigh_node through with the OGM has been received
  * @if_incoming: the interface on which this OGM was received on
  * @if_outgoing: the interface to which the OGM has to be forwarded to
  *
@@ -359,28 +301,57 @@ static u32 batadv_v_forward_penalty(struct batadv_priv *bat_priv,
  */
 static void batadv_v_ogm_forward(struct batadv_priv *bat_priv,
 				 const struct batadv_ogm2_packet *ogm_received,
-				 u32 throughput,
+				 struct batadv_orig_node *orig_node,
+				 struct batadv_neigh_node *neigh_node,
 				 struct batadv_hard_iface *if_incoming,
 				 struct batadv_hard_iface *if_outgoing)
 {
+	struct batadv_neigh_ifinfo *neigh_ifinfo = NULL;
+	struct batadv_orig_ifinfo *orig_ifinfo = NULL;
+	struct batadv_neigh_node *router = NULL;
 	struct batadv_ogm2_packet *ogm_forward;
 	unsigned char *skb_buff;
 	struct sk_buff *skb;
 	size_t packet_len;
 	u16 tvlv_len;
 
+	/* only forward for specific interfaces, not for the default one. */
+	if (if_outgoing == BATADV_IF_DEFAULT)
+		goto out;
+
+	orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
+	if (!orig_ifinfo)
+		goto out;
+
+	/* acquire possibly updated router */
+	router = batadv_orig_router_get(orig_node, if_outgoing);
+
+	/* strict rule: forward packets coming from the best next hop only */
+	if (neigh_node != router)
+		goto out;
+
+	/* don't forward the same seqno twice on one interface */
+	if (orig_ifinfo->last_seqno_forwarded == ntohl(ogm_received->seqno))
+		goto out;
+
+	orig_ifinfo->last_seqno_forwarded = ntohl(ogm_received->seqno);
+
 	if (ogm_received->ttl <= 1) {
 		batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
-		return;
+		goto out;
 	}
 
+	neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
+	if (!neigh_ifinfo)
+		goto out;
+
 	tvlv_len = ntohs(ogm_received->tvlv_len);
 
 	packet_len = BATADV_OGM2_HLEN + tvlv_len;
 	skb = netdev_alloc_skb_ip_align(if_outgoing->net_dev,
 					ETH_HLEN + packet_len);
 	if (!skb)
-		return;
+		goto out;
 
 	skb_reserve(skb, ETH_HLEN);
 	skb_buff = skb_put(skb, packet_len);
@@ -388,15 +359,23 @@ static void batadv_v_ogm_forward(struct batadv_priv *bat_priv,
 
 	/* apply forward penalty */
 	ogm_forward = (struct batadv_ogm2_packet *)skb_buff;
-	ogm_forward->throughput = htonl(throughput);
+	ogm_forward->throughput = htonl(neigh_ifinfo->bat_v.throughput);
 	ogm_forward->ttl--;
 
 	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
 		   "Forwarding OGM2 packet on %s: throughput %u, ttl %u, received via %s\n",
-		   if_outgoing->net_dev->name, throughput, ogm_forward->ttl,
-		   if_incoming->net_dev->name);
+		   if_outgoing->net_dev->name, ntohl(ogm_forward->throughput),
+		   ogm_forward->ttl, if_incoming->net_dev->name);
 
 	batadv_v_ogm_send_to_if(skb, if_outgoing);
+
+out:
+	if (orig_ifinfo)
+		batadv_orig_ifinfo_put(orig_ifinfo);
+	if (router)
+		batadv_neigh_node_put(router);
+	if (neigh_ifinfo)
+		batadv_neigh_ifinfo_put(neigh_ifinfo);
 }
 
 /**
@@ -493,8 +472,10 @@ out:
  * @neigh_node: the neigh_node through with the OGM has been received
  * @if_incoming: the interface where this packet was received
  * @if_outgoing: the interface for which the packet should be considered
+ *
+ * Return: true if the packet should be forwarded, false otherwise
  */
-static void batadv_v_ogm_route_update(struct batadv_priv *bat_priv,
+static bool batadv_v_ogm_route_update(struct batadv_priv *bat_priv,
 				      const struct ethhdr *ethhdr,
 				      const struct batadv_ogm2_packet *ogm2,
 				      struct batadv_orig_node *orig_node,
@@ -503,14 +484,14 @@ static void batadv_v_ogm_route_update(struct batadv_priv *bat_priv,
 				      struct batadv_hard_iface *if_outgoing)
 {
 	struct batadv_neigh_node *router = NULL;
-	struct batadv_neigh_ifinfo *neigh_ifinfo = NULL;
 	struct batadv_orig_node *orig_neigh_node = NULL;
-	struct batadv_orig_ifinfo *orig_ifinfo = NULL;
 	struct batadv_neigh_node *orig_neigh_router = NULL;
-
-	neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
-	if (!neigh_ifinfo)
-		goto out;
+	struct batadv_neigh_ifinfo *router_ifinfo = NULL, *neigh_ifinfo = NULL;
+	u32 router_throughput, neigh_throughput;
+	u32 router_last_seqno;
+	u32 neigh_last_seqno;
+	s32 neigh_seq_diff;
+	bool forward = false;
 
 	orig_neigh_node = batadv_v_ogm_orig_get(bat_priv, ethhdr->h_source);
 	if (!orig_neigh_node)
@@ -529,47 +510,57 @@ static void batadv_v_ogm_route_update(struct batadv_priv *bat_priv,
 		goto out;
 	}
 
-	if (router)
-		batadv_neigh_node_put(router);
+	/* Mark the OGM to be considered for forwarding, and update routes
+	 * if needed.
+	 */
+	forward = true;
 
-	/* Update routes, and check if the OGM is from the best next hop */
-	batadv_v_ogm_orig_update(bat_priv, orig_node, neigh_node, ogm2,
-				 if_outgoing);
+	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+		   "Searching and updating originator entry of received packet\n");
 
-	orig_ifinfo = batadv_orig_ifinfo_new(orig_node, if_outgoing);
-	if (!orig_ifinfo)
+	/* if this neighbor already is our next hop there is nothing
+	 * to change
+	 */
+	if (router == neigh_node)
 		goto out;
 
-	/* don't forward the same seqno twice on one interface */
-	if (orig_ifinfo->last_seqno_forwarded == ntohl(ogm2->seqno))
-		goto out;
+	/* don't consider neighbours with worse throughput.
+	 * also switch route if this seqno is BATADV_V_MAX_ORIGDIFF newer than
+	 * the last received seqno from our best next hop.
+	 */
+	if (router) {
+		router_ifinfo = batadv_neigh_ifinfo_get(router, if_outgoing);
+		neigh_ifinfo = batadv_neigh_ifinfo_get(neigh_node, if_outgoing);
 
-	/* acquire possibly updated router */
-	router = batadv_orig_router_get(orig_node, if_outgoing);
+		/* if these are not allocated, something is wrong. */
+		if (!router_ifinfo || !neigh_ifinfo)
+			goto out;
 
-	/* strict rule: forward packets coming from the best next hop only */
-	if (neigh_node != router)
-		goto out;
+		neigh_last_seqno = neigh_ifinfo->bat_v.last_seqno;
+		router_last_seqno = router_ifinfo->bat_v.last_seqno;
+		neigh_seq_diff = neigh_last_seqno - router_last_seqno;
+		router_throughput = router_ifinfo->bat_v.throughput;
+		neigh_throughput = neigh_ifinfo->bat_v.throughput;
 
-	/* only forward for specific interface, not for the default one. */
-	if (if_outgoing != BATADV_IF_DEFAULT) {
-		orig_ifinfo->last_seqno_forwarded = ntohl(ogm2->seqno);
-		batadv_v_ogm_forward(bat_priv, ogm2,
-				     neigh_ifinfo->bat_v.throughput,
-				     if_incoming, if_outgoing);
+		if ((neigh_seq_diff < BATADV_OGM_MAX_ORIGDIFF) &&
+		    (router_throughput >= neigh_throughput))
+			goto out;
 	}
 
+	batadv_update_route(bat_priv, orig_node, if_outgoing, neigh_node);
 out:
-	if (orig_ifinfo)
-		batadv_orig_ifinfo_put(orig_ifinfo);
 	if (router)
 		batadv_neigh_node_put(router);
 	if (orig_neigh_router)
 		batadv_neigh_node_put(orig_neigh_router);
 	if (orig_neigh_node)
 		batadv_orig_node_put(orig_neigh_node);
+	if (router_ifinfo)
+		batadv_neigh_ifinfo_put(router_ifinfo);
 	if (neigh_ifinfo)
 		batadv_neigh_ifinfo_put(neigh_ifinfo);
+
+	return forward;
 }
 
 /**
@@ -592,6 +583,7 @@ batadv_v_ogm_process_per_outif(struct batadv_priv *bat_priv,
 			       struct batadv_hard_iface *if_outgoing)
 {
 	int seqno_age;
+	bool forward;
 
 	/* first, update the metric with according sanity checks */
 	seqno_age = batadv_v_ogm_metric_update(bat_priv, ogm2, orig_node,
@@ -610,8 +602,14 @@ batadv_v_ogm_process_per_outif(struct batadv_priv *bat_priv,
 					       ntohs(ogm2->tvlv_len));
 
 	/* if the metric update went through, update routes if needed */
-	batadv_v_ogm_route_update(bat_priv, ethhdr, ogm2, orig_node,
-				  neigh_node, if_incoming, if_outgoing);
+	forward = batadv_v_ogm_route_update(bat_priv, ethhdr, ogm2, orig_node,
+					    neigh_node, if_incoming,
+					    if_outgoing);
+
+	/* if the routes have been processed correctly, check and forward */
+	if (forward)
+		batadv_v_ogm_forward(bat_priv, ogm2, orig_node, neigh_node,
+				     if_incoming, if_outgoing);
 }
 
 /**
@@ -713,9 +711,14 @@ static void batadv_v_ogm_process(const struct sk_buff *skb, int ogm_offset,
 		if (hard_iface->soft_iface != bat_priv->soft_iface)
 			continue;
 
+		if (!kref_get_unless_zero(&hard_iface->refcount))
+			continue;
+
 		batadv_v_ogm_process_per_outif(bat_priv, ethhdr, ogm_packet,
 					       orig_node, neigh_node,
 					       if_incoming, hard_iface);
+
+		batadv_hardif_put(hard_iface);
 	}
 	rcu_read_unlock();
 out: