net/sched/act_nat.c BUG

["Rodrigo Partearroyo González" <rpartearroyo@albentia.com>]

Hi all,

I have been testing Stateless NAT and found that ICMP packets with length less 
than 20 bytes were not correctly NAT'ed. I have found a BUG that makes taking 
into account IP header length twice, so ICMP packets smaller than 20 bytes 
were being dropped.

The proposed fix is:

Index: net/sched/act_nat.c
===================================================================
--- net/sched/act_nat.c
+++ net/sched/act_nat.c
@@ -202,7 +202,7 @@
        {
                struct icmphdr *icmph;
 
-               if (!pskb_may_pull(skb, ihl + sizeof(*icmph) + sizeof(*iph)))
+               if (!pskb_may_pull(skb, ihl + sizeof(*icmph)))
                        goto drop;
 
                icmph = (void *)(skb_network_header(skb) + ihl);

Please, consider applying it.
-- 
Rodrigo Partearroyo González
R&D Engineer

Albentia Systems S.A.
http://www.albentia.com
+34 914400213

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Parque Tecnológico de Leganés
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