batman-adv: use consume_skb for non-dropped packets

kfree_skb assumes that an skb is dropped after an failure and notes that.
consume_skb should be used in non-failure situations. Such information is
important for dropmonitor netlink which tells how many packets were dropped
and where this drop happened.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 0b9be62..310f391 100644 (file)
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -698,7 +698,7 @@ static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 
        forw_packet_aggr->skb = netdev_alloc_skb_ip_align(NULL, skb_size);
        if (!forw_packet_aggr->skb) {
-               batadv_forw_packet_free(forw_packet_aggr);
+               batadv_forw_packet_free(forw_packet_aggr, true);
                return;
        }
 
@@ -1611,7 +1611,7 @@ out:
        if (hardif_neigh)
                batadv_hardif_neigh_put(hardif_neigh);
 
-       kfree_skb(skb_priv);
+       consume_skb(skb_priv);
 }
 
 /**
@@ -1783,6 +1783,7 @@ static void batadv_iv_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;
+       bool dropped = false;
 
        delayed_work = to_delayed_work(work);
        forw_packet = container_of(delayed_work, struct batadv_forw_packet,
@@ -1792,8 +1793,10 @@ static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work)
        hlist_del(&forw_packet->list);
        spin_unlock_bh(&bat_priv->forw_bat_list_lock);
 
-       if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
+       if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) {
+               dropped = true;
                goto out;
+       }
 
        batadv_iv_ogm_emit(forw_packet);
 
@@ -1810,7 +1813,7 @@ static void batadv_iv_send_outstanding_bat_ogm_packet(struct work_struct *work)
                batadv_iv_ogm_schedule(forw_packet->if_incoming);
 
 out:
-       batadv_forw_packet_free(forw_packet);
+       batadv_forw_packet_free(forw_packet, dropped);
 }
 
 static int batadv_iv_ogm_receive(struct sk_buff *skb,
@@ -1851,7 +1854,7 @@ static int batadv_iv_ogm_receive(struct sk_buff *skb,
                ogm_packet = (struct batadv_ogm_packet *)packet_pos;
        }
 
-       kfree_skb(skb);
+       consume_skb(skb);
        return NET_RX_SUCCESS;
 }
 

diff --git a/net/batman-adv/fragmentation.c b/net/batman-adv/fragmentation.c
index 2b967a3..a2e28a1 100644 (file)
--- a/net/batman-adv/fragmentation.c
+++ b/net/batman-adv/fragmentation.c
@@ -42,17 +42,23 @@
 /**
  * batadv_frag_clear_chain - delete entries in the fragment buffer chain
  * @head: head of chain with entries.
+ * @dropped: whether the chain is cleared because all fragments are dropped
  *
  * Free fragments in the passed hlist. Should be called with appropriate lock.
  */
-static void batadv_frag_clear_chain(struct hlist_head *head)
+static void batadv_frag_clear_chain(struct hlist_head *head, bool dropped)
 {
        struct batadv_frag_list_entry *entry;
        struct hlist_node *node;
 
        hlist_for_each_entry_safe(entry, node, head, list) {
                hlist_del(&entry->list);
-               kfree_skb(entry->skb);
+
+               if (dropped)
+                       kfree_skb(entry->skb);
+               else
+                       consume_skb(entry->skb);
+
                kfree(entry);
        }
 }
@@ -73,7 +79,7 @@ void batadv_frag_purge_orig(struct batadv_orig_node *orig_node,
                spin_lock_bh(&chain->lock);
 
                if (!check_cb || check_cb(chain)) {
-                       batadv_frag_clear_chain(&chain->fragment_list);
+                       batadv_frag_clear_chain(&chain->fragment_list, true);
                        chain->size = 0;
                }
 
@@ -118,7 +124,7 @@ static bool batadv_frag_init_chain(struct batadv_frag_table_entry *chain,
                return false;
 
        if (!hlist_empty(&chain->fragment_list))
-               batadv_frag_clear_chain(&chain->fragment_list);
+               batadv_frag_clear_chain(&chain->fragment_list, true);
 
        chain->size = 0;
        chain->seqno = seqno;
@@ -220,7 +226,7 @@ out:
                 * exceeds the maximum size of one merged packet. Don't allow
                 * packets to have different total_size.
                 */
-               batadv_frag_clear_chain(&chain->fragment_list);
+               batadv_frag_clear_chain(&chain->fragment_list, true);
                chain->size = 0;
        } else if (ntohs(frag_packet->total_size) == chain->size) {
                /* All fragments received. Hand over chain to caller. */
@@ -254,6 +260,7 @@ batadv_frag_merge_packets(struct hlist_head *chain)
        struct batadv_frag_list_entry *entry;
        struct sk_buff *skb_out;
        int size, hdr_size = sizeof(struct batadv_frag_packet);
+       bool dropped = false;
 
        /* Remove first entry, as this is the destination for the rest of the
         * fragments.
@@ -270,6 +277,7 @@ batadv_frag_merge_packets(struct hlist_head *chain)
        if (pskb_expand_head(skb_out, 0, size - skb_out->len, GFP_ATOMIC) < 0) {
                kfree_skb(skb_out);
                skb_out = NULL;
+               dropped = true;
                goto free;
        }
 
@@ -291,7 +299,7 @@ batadv_frag_merge_packets(struct hlist_head *chain)
 
 free:
        /* Locking is not needed, because 'chain' is not part of any orig. */
-       batadv_frag_clear_chain(chain);
+       batadv_frag_clear_chain(chain, dropped);
        return skb_out;
 }
 

diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c
index c213dde..3af66d3 100644 (file)
--- a/net/batman-adv/network-coding.c
+++ b/net/batman-adv/network-coding.c
@@ -260,10 +260,16 @@ static void batadv_nc_path_put(struct batadv_nc_path *nc_path)
 /**
  * batadv_nc_packet_free - frees nc packet
  * @nc_packet: the nc packet to free
+ * @dropped: whether the packet is freed because is is dropped
  */
-static void batadv_nc_packet_free(struct batadv_nc_packet *nc_packet)
+static void batadv_nc_packet_free(struct batadv_nc_packet *nc_packet,
+                                 bool dropped)
 {
-       kfree_skb(nc_packet->skb);
+       if (dropped)
+               kfree_skb(nc_packet->skb);
+       else
+               consume_skb(nc_packet->skb);
+
        batadv_nc_path_put(nc_packet->nc_path);
        kfree(nc_packet);
 }
@@ -576,7 +582,7 @@ static void batadv_nc_send_packet(struct batadv_nc_packet *nc_packet)
 {
        batadv_send_unicast_skb(nc_packet->skb, nc_packet->neigh_node);
        nc_packet->skb = NULL;
-       batadv_nc_packet_free(nc_packet);
+       batadv_nc_packet_free(nc_packet, false);
 }
 
 /**
@@ -610,7 +616,7 @@ static bool batadv_nc_sniffed_purge(struct batadv_priv *bat_priv,
 
        /* purge nc packet */
        list_del(&nc_packet->list);
-       batadv_nc_packet_free(nc_packet);
+       batadv_nc_packet_free(nc_packet, true);
 
        res = true;
 
@@ -1208,11 +1214,11 @@ static bool batadv_nc_code_packets(struct batadv_priv *bat_priv,
        }
 
        /* skb_src is now coded into skb_dest, so free it */
-       kfree_skb(skb_src);
+       consume_skb(skb_src);
 
        /* avoid duplicate free of skb from nc_packet */
        nc_packet->skb = NULL;
-       batadv_nc_packet_free(nc_packet);
+       batadv_nc_packet_free(nc_packet, false);
 
        /* Send the coded packet and return true */
        batadv_send_unicast_skb(skb_dest, first_dest);
@@ -1399,7 +1405,7 @@ static void batadv_nc_skb_store_before_coding(struct batadv_priv *bat_priv,
        /* batadv_nc_skb_store_for_decoding() clones the skb, so we must free
         * our ref
         */
-       kfree_skb(skb);
+       consume_skb(skb);
 }
 
 /**
@@ -1723,7 +1729,7 @@ batadv_nc_skb_decode_packet(struct batadv_priv *bat_priv, struct sk_buff *skb,
        ether_addr_copy(unicast_packet->dest, orig_dest);
        unicast_packet->ttvn = ttvn;
 
-       batadv_nc_packet_free(nc_packet);
+       batadv_nc_packet_free(nc_packet, false);
        return unicast_packet;
 }
 
@@ -1860,7 +1866,7 @@ static int batadv_nc_recv_coded_packet(struct sk_buff *skb,
        return batadv_recv_unicast_packet(skb, recv_if);
 
 free_nc_packet:
-       batadv_nc_packet_free(nc_packet);
+       batadv_nc_packet_free(nc_packet, true);
        return NET_RX_DROP;
 }
 

diff --git a/net/batman-adv/send.c b/net/batman-adv/send.c
index d9bbb00..0f86293 100644 (file)
--- a/net/batman-adv/send.c
+++ b/net/batman-adv/send.c
@@ -451,13 +451,19 @@ int batadv_send_skb_via_gw(struct batadv_priv *bat_priv, struct sk_buff *skb,
 /**
  * batadv_forw_packet_free - free a forwarding packet
  * @forw_packet: The packet to free
+ * @dropped: whether the packet is freed because is is dropped
  *
  * This frees a forwarding packet and releases any resources it might
  * have claimed.
  */
-void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet)
+void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet,
+                            bool dropped)
 {
-       kfree_skb(forw_packet->skb);
+       if (dropped)
+               kfree_skb(forw_packet->skb);
+       else
+               consume_skb(forw_packet->skb);
+
        if (forw_packet->if_incoming)
                batadv_hardif_put(forw_packet->if_incoming);
        if (forw_packet->if_outgoing)
@@ -598,7 +604,7 @@ int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
        return NETDEV_TX_OK;
 
 err_packet_free:
-       batadv_forw_packet_free(forw_packet);
+       batadv_forw_packet_free(forw_packet, true);
 err:
        return NETDEV_TX_BUSY;
 }
@@ -613,6 +619,7 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
        struct sk_buff *skb1;
        struct net_device *soft_iface;
        struct batadv_priv *bat_priv;
+       bool dropped = false;
        u8 *neigh_addr;
        u8 *orig_neigh;
        int ret = 0;
@@ -627,11 +634,15 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
        hlist_del(&forw_packet->list);
        spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
 
-       if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
+       if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING) {
+               dropped = true;
                goto out;
+       }
 
-       if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet))
+       if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet)) {
+               dropped = true;
                goto out;
+       }
 
        bcast_packet = (struct batadv_bcast_packet *)forw_packet->skb->data;
 
@@ -709,7 +720,7 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
        }
 
 out:
-       batadv_forw_packet_free(forw_packet);
+       batadv_forw_packet_free(forw_packet, dropped);
 }
 
 void
@@ -750,7 +761,7 @@ batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
 
                if (pending) {
                        hlist_del(&forw_packet->list);
-                       batadv_forw_packet_free(forw_packet);
+                       batadv_forw_packet_free(forw_packet, true);
                }
        }
        spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
@@ -777,7 +788,7 @@ batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
 
                if (pending) {
                        hlist_del(&forw_packet->list);
-                       batadv_forw_packet_free(forw_packet);
+                       batadv_forw_packet_free(forw_packet, true);
                }
        }
        spin_unlock_bh(&bat_priv->forw_bat_list_lock);

diff --git a/net/batman-adv/send.h b/net/batman-adv/send.h
index 86009b5..c580194 100644 (file)
--- a/net/batman-adv/send.h
+++ b/net/batman-adv/send.h
@@ -27,7 +27,8 @@
 
 struct sk_buff;
 
-void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet);
+void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet,
+                            bool dropped);
 struct batadv_forw_packet *
 batadv_forw_packet_alloc(struct batadv_hard_iface *if_incoming,
                         struct batadv_hard_iface *if_outgoing,

diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 109f53b..2f0304e 100644 (file)
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -362,7 +362,7 @@ send:
                /* a copy is stored in the bcast list, therefore removing
                 * the original skb.
                 */
-               kfree_skb(skb);
+               consume_skb(skb);
 
        /* unicast packet */
        } else {