--- linux/net/ipv4/sysctl_net_ipv4.c	2008-12-13 17:56:16.000000000 -0600
+++ linux/net/ipv4/sysctl_net_ipv4.c	2008-12-17 13:57:26.000000000 -0600
@@ -28,6 +28,7 @@ static int ip_local_port_range_max[] = {
 
 extern seqlock_t sysctl_port_range_lock;
 extern int sysctl_local_port_range[2];
+extern int sysctl_raw_hdrincl_nomangle;
 
 /* Update system visible IP port range */
 static void set_local_port_range(int range[2])
@@ -745,6 +746,14 @@ static struct ctl_table ipv4_table[] = {
 		.strategy	= &sysctl_intvec,
 		.extra1		= &zero
 	},
+	{
+		.ctl_name	= CTL_UNNUMBERED,
+		.procname	= "raw_hdrincl_nomangle",
+		.data		= &sysctl_raw_hdrincl_nomangle,
+		.maxlen		= sizeof(sysctl_raw_hdrincl_nomangle),
+		.mode		= 0644,
+		.proc_handler	= &proc_dointvec
+	},
 	{ .ctl_name = 0 }
 };
 
--- linux/net/ipv4/raw.c	2008-12-13 17:56:16.000000000 -0600
+++ linux/net/ipv4/raw.c	2008-12-16 20:42:20.000000000 -0600
@@ -82,6 +82,9 @@ static struct raw_hashinfo raw_v4_hashin
 	.lock = __RW_LOCK_UNLOCKED(raw_v4_hashinfo.lock),
 };
 
+int sysctl_raw_hdrincl_nomangle __read_mostly;
+EXPORT_SYMBOL(sysctl_raw_hdrincl_nomangle);
+
 void raw_hash_sk(struct sock *sk)
 {
 	struct raw_hashinfo *h = sk->sk_prot->h.raw_hash;
@@ -358,7 +361,8 @@ static int raw_send_hdrinc(struct sock *
 
 	/* We don't modify invalid header */
 	iphlen = iph->ihl * 4;
-	if (iphlen >= sizeof(*iph) && iphlen <= length) {
+	if (iphlen >= sizeof(*iph) && iphlen <= length &&
+	    sysctl_raw_hdrincl_nomangle == 0) {
 		if (!iph->saddr)
 			iph->saddr = rt->rt_src;
 		iph->check   = 0;