netfilter: nf_nat: don't check if the tuple is unique when there isn't any other choice
The tuple got from unique_tuple() doesn't need to be really unique, so the
check for the unique tuple isn't necessary, when there isn't any other
choice. Eliminating the unnecessary nf_nat_used_tuple() can save some CPU
cycles too.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/net/ipv4/netfilter/nf_nat_proto_icmp.c b/net/ipv4/netfilter/nf_nat_proto_icmp.c
index 97003fe..5744c3e 100644
--- a/net/ipv4/netfilter/nf_nat_proto_icmp.c
+++ b/net/ipv4/netfilter/nf_nat_proto_icmp.c
@@ -42,10 +42,10 @@
if (!(range->flags & IP_NAT_RANGE_PROTO_SPECIFIED))
range_size = 0xFFFF;
- for (i = 0; i < range_size; i++, id++) {
+ for (i = 0; ; ++id) {
tuple->src.u.icmp.id = htons(ntohs(range->min.icmp.id) +
(id % range_size));
- if (!nf_nat_used_tuple(tuple, ct))
+ if (++i == range_size || !nf_nat_used_tuple(tuple, ct))
return;
}
return;