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>

1 files changed, 1 insertions, 7 deletions

diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index 8d64348e3cc0..1aa1722d0187 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -1196,14 +1196,8 @@ int batadv_recv_bcast_packet(struct sk_buff *skb,
 
         spin_unlock_bh(&orig_node->bcast_seqno_lock);
 
-        /* keep skb linear for crc calculation */
-        if (skb_linearize(skb) < 0)
-                goto out;
-
-        bcast_packet = (struct batadv_bcast_packet *)skb->data;
-
         /* check whether this has been sent by another originator before */
-        if (batadv_bla_check_bcast_duplist(bat_priv, bcast_packet, skb->len))
+        if (batadv_bla_check_bcast_duplist(bat_priv, skb))
                 goto out;
 
         /* rebroadcast packet */