[NETFILTER]: xt_hashlimit: fix limit off-by-one

Hashlimit doesn't account for the first packet, which is inconsistent
with the limit match.

Reported by ryan.castellucci@gmail.com, netfilter bugzilla #500.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/netfilter/ipt_hashlimit.c

@@ -454,15 +454,12 @@ hashlimit_match(const struct sk_buff *skb,
 		dh->rateinfo.credit_cap = user2credits(hinfo->cfg.avg * 
 							hinfo->cfg.burst);
 		dh->rateinfo.cost = user2credits(hinfo->cfg.avg);
-
-		spin_unlock_bh(&hinfo->lock);
-		return 1;
+	} else {
+		/* update expiration timeout */
+		dh->expires = now + msecs_to_jiffies(hinfo->cfg.expire);
+		rateinfo_recalc(dh, now);
 	}
 
-	/* update expiration timeout */
-	dh->expires = now + msecs_to_jiffies(hinfo->cfg.expire);
-
-	rateinfo_recalc(dh, now);
 	if (dh->rateinfo.credit >= dh->rateinfo.cost) {
 		/* We're underlimit. */
 		dh->rateinfo.credit -= dh->rateinfo.cost;