netfilter: restore lost #ifdef guarding defrag exception

Nir Tzachar <nir.tzachar@gmail.com> reported a warning when sending
fragments over loopback with NAT:

[ 6658.338121] WARNING: at net/ipv4/netfilter/nf_nat_standalone.c:89 nf_nat_fn+0x33/0x155()

The reason is that defragmentation is skipped for already tracked connections.
This is wrong in combination with NAT and ip_conntrack actually had some ifdefs
to avoid this behaviour when NAT is compiled in.

The entire "optimization" may seem a bit silly, for now simply restoring the
lost #ifdef is the easiest solution until we can come up with something better.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy 2008-10-14 11:56:59 -07:00 committed by David S. Miller
parent 4850137170
commit 38f7ac3eb7

View file

@ -41,12 +41,13 @@ static unsigned int ipv4_conntrack_defrag(unsigned int hooknum,
int (*okfn)(struct sk_buff *))
{
#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
#if !defined(CONFIG_NF_NAT) && !defined(CONFIG_NF_NAT_MODULE)
/* Previously seen (loopback)? Ignore. Do this before
fragment check. */
if (skb->nfct)
return NF_ACCEPT;
#endif
#endif
/* Gather fragments. */
if (ip_hdr(skb)->frag_off & htons(IP_MF | IP_OFFSET)) {
if (nf_ct_ipv4_gather_frags(skb,