From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mitsuru KANDA / =?ISO-2022-JP?B?GyRCP0BFRBsoQiAbJEI9PBsoQg==?=
 <mk@linux-ipv6.org>
Subject: [PATCH] IPV4 IPComp : threshold comparison
Date: Sun, 18 May 2003 02:00:01 +0900
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Hello,

I'm not sure how exactly we should check threshold.
In IPsec tunnel mode, the original comparison code 
seems to be including IP header length.

Could you check it?

Regards,
-mk


===== ipcomp.c 1.6 vs edited =====
--- 1.6/net/ipv4/ipcomp.c	Tue May 13 05:58:03 2003
+++ edited/ipcomp.c	Sun May 18 01:42:22 2003
@@ -168,6 +168,7 @@
 		struct iphdr	iph;
 		char 		buf[60];
 	} tmp_iph;
+	int hdr_len = 0;
 
 	if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) {
 		err = -EINVAL;
@@ -180,7 +181,11 @@
 		goto error;
 
 	/* Don't bother compressing */
-	if (skb->len < ipcd->threshold) {
+	if (!x->props.mode) {
+		iph = skb->nh.iph;
+		hdr_len = iph->ihl * 4;
+	}
+	if ((skb->len - hdr_len) < ipcd->threshold) {
 		if (x->props.mode) {
 			ipcomp_tunnel_encap(x, skb);
 			iph = skb->nh.iph;