batman-adv: Fix TT sync flags for intermediate TT responses

BugLink: https://bugs.launchpad.net/bugs/1868629

commit 7072337e 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: e9c00136 ("batman-adv: fix tt_global_entries flags update")
Reported-by: Leonardo Mörlein <me@irrelefant.net>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

net/batman-adv/translation-table.c

@@ -1249,7 +1249,8 @@ batadv_tt_global_orig_entry_find(const struct batadv_tt_global_entry *entry,
  */
 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 struct batadv_tt_global_entry *entry,
 	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 batadv_priv *bat_priv,
 			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 @@ batadv_tt_req_node_new(struct batadv_priv *bat_priv,
  *
  * 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 void *entry_ptr,
 				       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 void *entry_ptr,
 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(struct batadv_priv *bat_priv,
 			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));