[PATCH 4.4 71/93] batman-adv: Fix TT sync flags for intermediate TT responses

[Greg Kroah-Hartman]

From: Linus Lü <linus.luessing@xxxxxxxxx>

commit 7072337e52b3e9d5460500d8dc9cbc1ba2db084c upstream.

The previous TT sync fix so far only fixed TT responses issued by the
target node directly. So far, TT responses issued by intermediate nodes
still lead to the wrong flags being added, leading to CRC mismatches.

This behaviour was observed at Freifunk Hannover in a 800 nodes setup
where a considerable amount of nodes were still infected with 'WI'
TT flags even with (most) nodes having the previous TT sync fix applied.

I was able to reproduce the issue with intermediate TT responses in a
four node test setup and this patch fixes this issue by ensuring to
use the per originator instead of the summarized, OR'd ones.

Fixes: e9c00136a475 ("batman-adv: fix tt_global_entries flags update")
Reported-by: Leonardo Möin <me@xxxxxxxxxxxxxx>
Signed-off-by: Linus Lü <linus.luessing@xxxxxxxxx>
Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx>
Signed-off-by: Simon Wunderlich <sw@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Sven Eckelmann <sven@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/batman-adv/translation-table.c |   37 +++++++++++++++++++++++++++++--------
 1 file changed, 29 insertions(+), 8 deletions(-)

--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -1249,7 +1249,8 @@ batadv_tt_global_orig_entry_find(const s
  */
 static bool
 batadv_tt_global_entry_has_orig(const struct batadv_tt_global_entry *entry,
-				const struct batadv_orig_node *orig_node)
+				const struct batadv_orig_node *orig_node,
+				u8 *flags)
 {
 	struct batadv_tt_orig_list_entry *orig_entry;
 	bool found = false;
@@ -1257,6 +1258,10 @@ batadv_tt_global_entry_has_orig(const st
 	orig_entry = batadv_tt_global_orig_entry_find(entry, orig_node);
 	if (orig_entry) {
 		found = true;
+
+		if (flags)
+			*flags = orig_entry->flags;
+
 		batadv_tt_orig_list_entry_free_ref(orig_entry);
 	}
 
@@ -1432,7 +1437,7 @@ static bool batadv_tt_global_add(struct
 			if (!(common->flags & BATADV_TT_CLIENT_TEMP))
 				goto out;
 			if (batadv_tt_global_entry_has_orig(tt_global_entry,
-							    orig_node))
+							    orig_node, NULL))
 				goto out_remove;
 			batadv_tt_global_del_orig_list(tt_global_entry);
 			goto add_orig_entry;
@@ -2366,17 +2371,24 @@ unlock:
  *
  * Returns 1 if the entry is a valid, 0 otherwise.
  */
-static int batadv_tt_local_valid(const void *entry_ptr, const void *data_ptr)
+static int batadv_tt_local_valid(const void *entry_ptr,
+				 const void *data_ptr,
+				 u8 *flags)
 {
 	const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
 
 	if (tt_common_entry->flags & BATADV_TT_CLIENT_NEW)
 		return 0;
+
+	if (flags)
+		*flags = tt_common_entry->flags;
+
 	return 1;
 }
 
 static int batadv_tt_global_valid(const void *entry_ptr,
-				  const void *data_ptr)
+				  const void *data_ptr,
+				  u8 *flags)
 {
 	const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
 	const struct batadv_tt_global_entry *tt_global_entry;
@@ -2390,7 +2402,8 @@ static int batadv_tt_global_valid(const
 				       struct batadv_tt_global_entry,
 				       common);
 
-	return batadv_tt_global_entry_has_orig(tt_global_entry, orig_node);
+	return batadv_tt_global_entry_has_orig(tt_global_entry, orig_node,
+					       flags);
 }
 
 /**
@@ -2406,18 +2419,25 @@ static int batadv_tt_global_valid(const
 static void batadv_tt_tvlv_generate(struct batadv_priv *bat_priv,
 				    struct batadv_hashtable *hash,
 				    void *tvlv_buff, u16 tt_len,
-				    int (*valid_cb)(const void *, const void *),
+				    int (*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;
 	struct hlist_head *head;
 	u16 tt_tot, tt_num_entries = 0;
+	u8 flags;
+	bool ret;
 	u32 i;
 
 	tt_tot = batadv_tt_entries(tt_len);
 	tt_change = (struct batadv_tvlv_tt_change *)tvlv_buff;
 
+	if (!valid_cb)
+		return;
+
 	rcu_read_lock();
 	for (i = 0; i < hash->size; i++) {
 		head = &hash->table[i];
@@ -2427,11 +2447,12 @@ static void batadv_tt_tvlv_generate(stru
 			if (tt_tot == tt_num_entries)
 				break;
 
-			if ((valid_cb) && (!valid_cb(tt_common_entry, cb_data)))
+			ret = valid_cb(tt_common_entry, cb_data, &flags);
+			if (!ret)
 				continue;
 
 			ether_addr_copy(tt_change->addr, tt_common_entry->addr);
-			tt_change->flags = tt_common_entry->flags;
+			tt_change->flags = flags;
 			tt_change->vid = htons(tt_common_entry->vid);
 			memset(tt_change->reserved, 0,
 			       sizeof(tt_change->reserved));