batman-adv: Fix broadcast duplist for fragmentation
If the skb is fragmented, the checksum must be computed on the
individual fragments, just using skb->data may fail on fragmented
data. Instead of doing linearizing the packet, use the new
batadv_crc32 to do that more efficiently- it should not hurt
replacing the old crc16 by the new crc32.
Reported-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index 7ffef8b..5aebe93 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -1249,8 +1249,7 @@
/**
* batadv_bla_check_bcast_duplist
* @bat_priv: the bat priv with all the soft interface information
- * @bcast_packet: encapsulated broadcast frame plus batman header
- * @bcast_packet_len: length of encapsulated broadcast frame plus batman header
+ * @skb: contains the bcast_packet to be checked
*
* check if it is on our broadcast list. Another gateway might
* have sent the same packet because it is connected to the same backbone,
@@ -1262,20 +1261,17 @@
* the same host however as this might be intended.
*/
int batadv_bla_check_bcast_duplist(struct batadv_priv *bat_priv,
- struct batadv_bcast_packet *bcast_packet,
- int bcast_packet_len)
+ struct sk_buff *skb)
{
- int i, length, curr, ret = 0;
- uint8_t *content;
- uint16_t crc;
+ int i, curr, ret = 0;
+ __be32 crc;
+ struct batadv_bcast_packet *bcast_packet;
struct batadv_bcast_duplist_entry *entry;
- length = bcast_packet_len - sizeof(*bcast_packet);
- content = (uint8_t *)bcast_packet;
- content += sizeof(*bcast_packet);
+ bcast_packet = (struct batadv_bcast_packet *)skb->data;
/* calculate the crc ... */
- crc = crc16(0, content, length);
+ crc = batadv_skb_crc32(skb, (u8 *)(bcast_packet + 1));
spin_lock_bh(&bat_priv->bla.bcast_duplist_lock);