Staging: batman-adv: fix crash when new OGM is generated

If aggregation is not enabled the local translation table can grow
much bigger and expects to fill a full ethernet packet.

Reported-by: Sam Yeung <sam.cwyeung@gmail.com>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/batman-adv/aggregation.c

@@ -123,8 +123,14 @@ static void new_aggregated_packet(unsigned char *packet_buff, int packet_len,
 		return;
 	}
 
-	forw_packet_aggr->skb = dev_alloc_skb(MAX_AGGREGATION_BYTES +
-					      sizeof(struct ethhdr));
+	if ((atomic_read(&bat_priv->aggregation_enabled)) &&
+	    (packet_len < MAX_AGGREGATION_BYTES))
+		forw_packet_aggr->skb = dev_alloc_skb(MAX_AGGREGATION_BYTES +
+						      sizeof(struct ethhdr));
+	else
+		forw_packet_aggr->skb = dev_alloc_skb(packet_len +
+						      sizeof(struct ethhdr));
+
 	if (!forw_packet_aggr->skb) {
 		if (!own_packet)
 			atomic_inc(&bat_priv->batman_queue_left);