[IPV4]: Always pass ip_options pointer into ip_options_compile.

This makes code a bit more uniform and straigthforward.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv4/ip_input.c

@@ -283,13 +283,14 @@ static inline int ip_rcv_options(struct sk_buff *skb)
 	}
 
 	iph = ip_hdr(skb);
+	opt = &(IPCB(skb)->opt);
+	opt->optlen = iph->ihl*4 - sizeof(struct iphdr);
 
-	if (ip_options_compile(NULL, skb)) {
+	if (ip_options_compile(opt, skb)) {
 		IP_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
 		goto drop;
 	}
 
-	opt = &(IPCB(skb)->opt);
 	if (unlikely(opt->srr)) {
 		struct in_device *in_dev = in_dev_get(dev);
 		if (in_dev) {

net/ipv4/ip_options.c

@@ -255,17 +255,14 @@ int ip_options_compile(struct ip_options * opt, struct sk_buff * skb)
 	unsigned char * optptr;
 	int optlen;
 	unsigned char * pp_ptr = NULL;
-	struct rtable *rt = skb ? skb->rtable : NULL;
+	struct rtable *rt = NULL;
 
-	if (!opt) {
-		opt = &(IPCB(skb)->opt);
-		iph = skb_network_header(skb);
-		opt->optlen = ((struct iphdr *)iph)->ihl*4 - sizeof(struct iphdr);
-		optptr = iph + sizeof(struct iphdr);
-	} else {
+	if (skb != NULL) {
+		rt = skb->rtable;
+		optptr = (unsigned char *)&(ip_hdr(skb)[1]);
+	} else
 		optptr = opt->__data;
 	iph = optptr - sizeof(struct iphdr);
-	}
 
 	for (l = opt->optlen; l > 0; ) {
 		switch (*optptr) {