1 files changed, 75 insertions, 75 deletions

diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index b44c382226a1..3c0a14a582e4 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -15,6 +15,7 @@
 #include <linux/compiler.h>
 #include <linux/container_of.h>
 #include <linux/crc32c.h>
+#include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/etherdevice.h>
 #include <linux/gfp.h>
@@ -39,7 +40,6 @@
 #include <linux/workqueue.h>
 #include <net/genetlink.h>
 #include <net/netlink.h>
-#include <net/sock.h>
 #include <uapi/linux/batadv_packet.h>
 #include <uapi/linux/batman_adv.h>
 
@@ -423,8 +423,8 @@ static void batadv_tt_local_event(struct batadv_priv *bat_priv,
 	struct batadv_tt_change_node *tt_change_node, *entry, *safe;
 	struct batadv_tt_common_entry *common = &tt_local_entry->common;
 	u8 flags = common->flags | event_flags;
-	bool event_removed = false;
 	bool del_op_requested, del_op_entry;
+	size_t changes;
 
 	tt_change_node = kmem_cache_alloc(batadv_tt_change_cache, GFP_ATOMIC);
 	if (!tt_change_node)
@@ -438,51 +438,45 @@ static void batadv_tt_local_event(struct batadv_priv *bat_priv,
 
 	del_op_requested = flags & BATADV_TT_CLIENT_DEL;
 
-	/* check for ADD+DEL or DEL+ADD events */
+	/* check for ADD+DEL, DEL+ADD, ADD+ADD or DEL+DEL events */
 	spin_lock_bh(&bat_priv->tt.changes_list_lock);
+	changes = READ_ONCE(bat_priv->tt.local_changes);
 	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
 				 list) {
 		if (!batadv_compare_eth(entry->change.addr, common->addr))
 			continue;
 
-		/* DEL+ADD in the same orig interval have no effect and can be
-		 * removed to avoid silly behaviour on the receiver side. The
-		 * other way around (ADD+DEL) can happen in case of roaming of
-		 * a client still in the NEW state. Roaming of NEW clients is
-		 * now possible due to automatically recognition of "temporary"
-		 * clients
-		 */
 		del_op_entry = entry->change.flags & BATADV_TT_CLIENT_DEL;
-		if (!del_op_requested && del_op_entry)
-			goto del;
-		if (del_op_requested && !del_op_entry)
-			goto del;
-
-		/* this is a second add in the same originator interval. It
-		 * means that flags have been changed: update them!
-		 */
-		if (!del_op_requested && !del_op_entry)
+		if (del_op_requested != del_op_entry) {
+			/* DEL+ADD in the same orig interval have no effect and
+			 * can be removed to avoid silly behaviour on the
+			 * receiver side. The  other way around (ADD+DEL) can
+			 * happen in case of roaming of  a client still in the
+			 * NEW state. Roaming of NEW clients is now possible due
+			 * to automatically recognition of "temporary" clients
+			 */
+			list_del(&entry->list);
+			kmem_cache_free(batadv_tt_change_cache, entry);
+			changes--;
+		} else {
+			/* this is a second add or del in the same originator
+			 * interval. It could mean that flags have been changed
+			 * (e.g. double add): update them
+			 */
 			entry->change.flags = flags;
+		}
 
-		continue;
-del:
-		list_del(&entry->list);
-		kmem_cache_free(batadv_tt_change_cache, entry);
 		kmem_cache_free(batadv_tt_change_cache, tt_change_node);
-		event_removed = true;
-		goto unlock;
+		goto update_changes;
 	}
 
 	/* track the change in the OGMinterval list */
 	list_add_tail(&tt_change_node->list, &bat_priv->tt.changes_list);
+	changes++;
 
-unlock:
+update_changes:
+	WRITE_ONCE(bat_priv->tt.local_changes, changes);
 	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
-
-	if (event_removed)
-		atomic_dec(&bat_priv->tt.local_changes);
-	else
-		atomic_inc(&bat_priv->tt.local_changes);
 }
 
 /**
@@ -948,16 +942,25 @@ static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
 	int tt_diff_len, tt_change_len = 0;
 	int tt_diff_entries_num = 0;
 	int tt_diff_entries_count = 0;
+	bool drop_changes = false;
+	size_t tt_extra_len = 0;
 	u16 tvlv_len;
 
-	tt_diff_entries_num = atomic_read(&bat_priv->tt.local_changes);
+	tt_diff_entries_num = READ_ONCE(bat_priv->tt.local_changes);
 	tt_diff_len = batadv_tt_len(tt_diff_entries_num);
 
 	/* if we have too many changes for one packet don't send any
-	 * and wait for the tt table request which will be fragmented
+	 * and wait for the tt table request so we can reply with the full
+	 * (fragmented) table.
+	 *
+	 * The local change history should still be cleaned up so the next
+	 * TT round can start again with a clean state.
 	 */
-	if (tt_diff_len > bat_priv->soft_iface->mtu)
+	if (tt_diff_len > bat_priv->soft_iface->mtu) {
 		tt_diff_len = 0;
+		tt_diff_entries_num = 0;
+		drop_changes = true;
+	}
 
 	tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv, &tt_data,
 						     &tt_change, &tt_diff_len);
@@ -966,11 +969,11 @@ static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
 
 	tt_data->flags = BATADV_TT_OGM_DIFF;
 
-	if (tt_diff_len == 0)
+	if (!drop_changes && tt_diff_len == 0)
 		goto container_register;
 
 	spin_lock_bh(&bat_priv->tt.changes_list_lock);
-	atomic_set(&bat_priv->tt.local_changes, 0);
+	WRITE_ONCE(bat_priv->tt.local_changes, 0);
 
 	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
 				 list) {
@@ -985,6 +988,9 @@ static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
 	}
 	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 
+	tt_extra_len = batadv_tt_len(tt_diff_entries_num -
+				     tt_diff_entries_count);
+
 	/* Keep the buffer for possible tt_request */
 	spin_lock_bh(&bat_priv->tt.last_changeset_lock);
 	kfree(bat_priv->tt.last_changeset);
@@ -993,6 +999,7 @@ static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
 	tt_change_len = batadv_tt_len(tt_diff_entries_count);
 	/* check whether this new OGM has no changes due to size problems */
 	if (tt_diff_entries_count > 0) {
+		tt_diff_len -= tt_extra_len;
 		/* if kmalloc() fails we will reply with the full table
 		 * instead of providing the diff
 		 */
@@ -1005,6 +1012,8 @@ static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
 	}
 	spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
 
+	/* Remove extra packet space for OGM */
+	tvlv_len -= tt_extra_len;
 container_register:
 	batadv_tvlv_container_register(bat_priv, BATADV_TVLV_TT, 1, tt_data,
 				       tvlv_len);
@@ -1121,26 +1130,18 @@ batadv_tt_local_dump_bucket(struct sk_buff *msg, u32 portid,
  */
 int batadv_tt_local_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_priv *bat_priv;
 	struct batadv_hard_iface *primary_if = NULL;
 	struct batadv_hashtable *hash;
 	int ret;
-	int ifindex;
 	int bucket = cb->args[0];
 	int idx = cb->args[1];
 	int portid = NETLINK_CB(cb->skb).portid;
 
-	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;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 
@@ -1380,7 +1381,7 @@ static void batadv_tt_changes_list_free(struct batadv_priv *bat_priv)
 		kmem_cache_free(batadv_tt_change_cache, entry);
 	}
 
-	atomic_set(&bat_priv->tt.local_changes, 0);
+	WRITE_ONCE(bat_priv->tt.local_changes, 0);
 	spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 }
 
@@ -1896,28 +1897,20 @@ batadv_tt_global_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
  */
 int batadv_tt_global_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
-	struct net *net = sock_net(cb->skb->sk);
 	struct net_device *soft_iface;
 	struct batadv_priv *bat_priv;
 	struct batadv_hard_iface *primary_if = NULL;
 	struct batadv_hashtable *hash;
 	struct hlist_head *head;
 	int ret;
-	int ifindex;
 	int bucket = cb->args[0];
 	int idx = cb->args[1];
 	int sub = cb->args[2];
 	int portid = NETLINK_CB(cb->skb).portid;
 
-	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;
-	}
+	soft_iface = batadv_netlink_get_softif(cb);
+	if (IS_ERR(soft_iface))
+		return PTR_ERR(soft_iface);
 
 	bat_priv = netdev_priv(soft_iface);
 
@@ -2705,14 +2698,16 @@ static bool batadv_tt_global_valid(const void *entry_ptr,
  *
  * Fills the tvlv buff with the tt entries from the specified hash. If valid_cb
  * is not provided then this becomes a no-op.
+ *
+ * Return: Remaining unused length in tvlv_buff.
  */
-static void batadv_tt_tvlv_generate(struct batadv_priv *bat_priv,
-				    struct batadv_hashtable *hash,
-				    void *tvlv_buff, u16 tt_len,
-				    bool (*valid_cb)(const void *,
-						     const void *,
-						     u8 *flags),
-				    void *cb_data)
+static u16 batadv_tt_tvlv_generate(struct batadv_priv *bat_priv,
+				   struct batadv_hashtable *hash,
+				   void *tvlv_buff, u16 tt_len,
+				   bool (*valid_cb)(const void *,
+						    const void *,
+						    u8 *flags),
+				   void *cb_data)
 {
 	struct batadv_tt_common_entry *tt_common_entry;
 	struct batadv_tvlv_tt_change *tt_change;
@@ -2726,7 +2721,7 @@ static void batadv_tt_tvlv_generate(struct batadv_priv *bat_priv,
 	tt_change = tvlv_buff;
 
 	if (!valid_cb)
-		return;
+		return tt_len;
 
 	rcu_read_lock();
 	for (i = 0; i < hash->size; i++) {
@@ -2752,6 +2747,8 @@ static void batadv_tt_tvlv_generate(struct batadv_priv *bat_priv,
 		}
 	}
 	rcu_read_unlock();
+
+	return batadv_tt_len(tt_tot - tt_num_entries);
 }
 
 /**
@@ -3022,10 +3019,11 @@ static bool batadv_send_other_tt_response(struct batadv_priv *bat_priv,
 			goto out;
 
 		/* fill the rest of the tvlv with the real TT entries */
-		batadv_tt_tvlv_generate(bat_priv, bat_priv->tt.global_hash,
-					tt_change, tt_len,
-					batadv_tt_global_valid,
-					req_dst_orig_node);
+		tvlv_len -= batadv_tt_tvlv_generate(bat_priv,
+						    bat_priv->tt.global_hash,
+						    tt_change, tt_len,
+						    batadv_tt_global_valid,
+						    req_dst_orig_node);
 	}
 
 	/* Don't send the response, if larger than fragmented packet. */
@@ -3149,9 +3147,11 @@ static bool batadv_send_my_tt_response(struct batadv_priv *bat_priv,
 			goto out;
 
 		/* fill the rest of the tvlv with the real TT entries */
-		batadv_tt_tvlv_generate(bat_priv, bat_priv->tt.local_hash,
-					tt_change, tt_len,
-					batadv_tt_local_valid, NULL);
+		tvlv_len -= batadv_tt_tvlv_generate(bat_priv,
+						    bat_priv->tt.local_hash,
+						    tt_change, tt_len,
+						    batadv_tt_local_valid,
+						    NULL);
 	}
 
 	tvlv_tt_data->flags = BATADV_TT_RESPONSE;
@@ -3634,7 +3634,7 @@ static void batadv_tt_local_commit_changes_nolock(struct batadv_priv *bat_priv)
 {
 	lockdep_assert_held(&bat_priv->tt.commit_lock);
 
-	if (atomic_read(&bat_priv->tt.local_changes) < 1) {
+	if (READ_ONCE(bat_priv->tt.local_changes) == 0) {
 		if (!batadv_atomic_dec_not_zero(&bat_priv->tt.ogm_append_cnt))
 			batadv_tt_tvlv_container_update(bat_priv);
 		return;