[SK_BUFF]: Introduce skb_network_header()

For the places where we need a pointer to the network header, it is still legal
to touch skb->nh.raw directly if just adding to, subtracting from or setting it
to another layer header.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 2ff0704..7b917f8 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -693,7 +693,8 @@
 	if (np->rxopt.all) {
 		if ((opt->hop && (np->rxopt.bits.hopopts ||
 				  np->rxopt.bits.ohopopts)) ||
-		    ((IPV6_FLOWINFO_MASK & *(__be32*)skb->nh.raw) &&
+		    ((IPV6_FLOWINFO_MASK &
+		      *(__be32 *)skb_network_header(skb)) &&
 		     np->rxopt.bits.rxflow) ||
 		    (opt->srcrt && (np->rxopt.bits.srcrt ||
 		     np->rxopt.bits.osrcrt)) ||
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index dc68b72..1c91438 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -238,8 +238,8 @@
 	top_iph = (struct ipv6hdr *)skb->data;
 	top_iph->payload_len = htons(skb->len - sizeof(*top_iph));
 
-	nexthdr = *skb->nh.raw;
-	*skb->nh.raw = IPPROTO_AH;
+	nexthdr = *skb_network_header(skb);
+	*skb_network_header(skb) = IPPROTO_AH;
 
 	/* When there are no extension headers, we only need to save the first
 	 * 8 bytes of the base IP header.
@@ -341,7 +341,7 @@
 	    pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
 		goto out;
 
-	hdr_len = skb->data - skb->nh.raw;
+	hdr_len = skb->data - skb_network_header(skb);
 	ah = (struct ipv6_auth_hdr*)skb->data;
 	ahp = x->data;
 	nexthdr = ah->nexthdr;
@@ -354,7 +354,7 @@
 	if (!pskb_may_pull(skb, ah_hlen))
 		goto out;
 
-	tmp_hdr = kmemdup(skb->nh.raw, hdr_len, GFP_ATOMIC);
+	tmp_hdr = kmemdup(skb_network_header(skb), hdr_len, GFP_ATOMIC);
 	if (!tmp_hdr)
 		goto out;
 	if (ipv6_clear_mutable_options(skb->nh.ipv6h, hdr_len, XFRM_POLICY_IN))
@@ -382,7 +382,9 @@
 		}
 	}
 
-	skb->h.raw = memcpy(skb->nh.raw += ah_hlen, tmp_hdr, hdr_len);
+	skb->nh.raw += ah_hlen;
+	memcpy(skb_network_header(skb), tmp_hdr, hdr_len);
+	skb->h.raw = skb->nh.raw;
 	__skb_pull(skb, ah_hlen + hdr_len);
 
 	kfree(tmp_hdr);
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index 31a20f1..7a86db6 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -227,7 +227,8 @@
 	serr->ee.ee_pad = 0;
 	serr->ee.ee_info = info;
 	serr->ee.ee_data = 0;
-	serr->addr_offset = (u8*)&(((struct ipv6hdr*)(icmph+1))->daddr) - skb->nh.raw;
+	serr->addr_offset = (u8 *)&(((struct ipv6hdr *)(icmph + 1))->daddr) -
+				  skb_network_header(skb);
 	serr->port = port;
 
 	skb->h.raw = payload;
@@ -264,7 +265,7 @@
 	serr->ee.ee_pad = 0;
 	serr->ee.ee_info = info;
 	serr->ee.ee_data = 0;
-	serr->addr_offset = (u8*)&iph->daddr - skb->nh.raw;
+	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 	serr->port = fl->fl_ip_dport;
 
 	skb->h.raw = skb->tail;
@@ -310,21 +311,24 @@
 
 	sin = (struct sockaddr_in6 *)msg->msg_name;
 	if (sin) {
+		const unsigned char *nh = skb_network_header(skb);
 		sin->sin6_family = AF_INET6;
 		sin->sin6_flowinfo = 0;
 		sin->sin6_port = serr->port;
 		sin->sin6_scope_id = 0;
 		if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP6) {
 			ipv6_addr_copy(&sin->sin6_addr,
-			  (struct in6_addr *)(skb->nh.raw + serr->addr_offset));
+				  (struct in6_addr *)(nh + serr->addr_offset));
 			if (np->sndflow)
-				sin->sin6_flowinfo = *(__be32*)(skb->nh.raw + serr->addr_offset - 24) & IPV6_FLOWINFO_MASK;
+				sin->sin6_flowinfo =
+					(*(__be32 *)(nh + serr->addr_offset - 24) &
+					 IPV6_FLOWINFO_MASK);
 			if (ipv6_addr_type(&sin->sin6_addr) & IPV6_ADDR_LINKLOCAL)
 				sin->sin6_scope_id = IP6CB(skb)->iif;
 		} else {
 			ipv6_addr_set(&sin->sin6_addr, 0, 0,
 				      htonl(0xffff),
-				      *(__be32*)(skb->nh.raw + serr->addr_offset));
+				      *(__be32 *)(nh + serr->addr_offset));
 		}
 	}
 
@@ -382,6 +386,7 @@
 {
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct inet6_skb_parm *opt = IP6CB(skb);
+	unsigned char *nh = skb_network_header(skb);
 
 	if (np->rxopt.bits.rxinfo) {
 		struct in6_pktinfo src_info;
@@ -401,14 +406,14 @@
 		put_cmsg(msg, SOL_IPV6, IPV6_TCLASS, sizeof(tclass), &tclass);
 	}
 
-	if (np->rxopt.bits.rxflow && (*(__be32*)skb->nh.raw & IPV6_FLOWINFO_MASK)) {
-		__be32 flowinfo = *(__be32*)skb->nh.raw & IPV6_FLOWINFO_MASK;
+	if (np->rxopt.bits.rxflow && (*(__be32 *)nh & IPV6_FLOWINFO_MASK)) {
+		__be32 flowinfo = *(__be32 *)nh & IPV6_FLOWINFO_MASK;
 		put_cmsg(msg, SOL_IPV6, IPV6_FLOWINFO, sizeof(flowinfo), &flowinfo);
 	}
 
 	/* HbH is allowed only once */
 	if (np->rxopt.bits.hopopts && opt->hop) {
-		u8 *ptr = skb->nh.raw + opt->hop;
+		u8 *ptr = nh + opt->hop;
 		put_cmsg(msg, SOL_IPV6, IPV6_HOPOPTS, (ptr[1]+1)<<3, ptr);
 	}
 
@@ -428,7 +433,7 @@
 
 		while (off <= opt->lastopt) {
 			unsigned len;
-			u8 *ptr = skb->nh.raw + off;
+			u8 *ptr = nh + off;
 
 			switch(nexthdr) {
 			case IPPROTO_DSTOPTS:
@@ -470,19 +475,19 @@
 		put_cmsg(msg, SOL_IPV6, IPV6_2292HOPLIMIT, sizeof(hlim), &hlim);
 	}
 	if (np->rxopt.bits.ohopopts && opt->hop) {
-		u8 *ptr = skb->nh.raw + opt->hop;
+		u8 *ptr = nh + opt->hop;
 		put_cmsg(msg, SOL_IPV6, IPV6_2292HOPOPTS, (ptr[1]+1)<<3, ptr);
 	}
 	if (np->rxopt.bits.odstopts && opt->dst0) {
-		u8 *ptr = skb->nh.raw + opt->dst0;
+		u8 *ptr = nh + opt->dst0;
 		put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 	}
 	if (np->rxopt.bits.osrcrt && opt->srcrt) {
-		struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(skb->nh.raw + opt->srcrt);
+		struct ipv6_rt_hdr *rthdr = (struct ipv6_rt_hdr *)(nh + opt->srcrt);
 		put_cmsg(msg, SOL_IPV6, IPV6_2292RTHDR, (rthdr->hdrlen+1) << 3, rthdr);
 	}
 	if (np->rxopt.bits.odstopts && opt->dst1) {
-		u8 *ptr = skb->nh.raw + opt->dst1;
+		u8 *ptr = nh + opt->dst1;
 		put_cmsg(msg, SOL_IPV6, IPV6_2292DSTOPTS, (ptr[1]+1)<<3, ptr);
 	}
 	return 0;
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 363e63f..6e6b57a 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -92,8 +92,8 @@
 	top_iph = (struct ipv6hdr *)__skb_push(skb, hdr_len);
 	esph = (struct ipv6_esp_hdr *)skb->h.raw;
 	top_iph->payload_len = htons(skb->len + alen - sizeof(*top_iph));
-	*(u8*)(trailer->tail - 1) = *skb->nh.raw;
-	*skb->nh.raw = IPPROTO_ESP;
+	*(u8 *)(trailer->tail - 1) = *skb_network_header(skb);
+	*skb_network_header(skb) = IPPROTO_ESP;
 
 	esph->spi = x->id.spi;
 	esph->seq_no = htonl(++x->replay.oseq);
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index fce5abd..9ebf120 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -50,13 +50,14 @@
 
 int ipv6_find_tlv(struct sk_buff *skb, int offset, int type)
 {
-	int packet_len = skb->tail - skb->nh.raw;
+	const unsigned char *nh = skb_network_header(skb);
+	int packet_len = skb->tail - nh;
 	struct ipv6_opt_hdr *hdr;
 	int len;
 
 	if (offset + 2 > packet_len)
 		goto bad;
-	hdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
+	hdr = (struct ipv6_opt_hdr *)(nh + offset);
 	len = ((hdr->hdrlen + 1) << 3);
 
 	if (offset + len > packet_len)
@@ -66,7 +67,7 @@
 	len -= 2;
 
 	while (len > 0) {
-		int opttype = skb->nh.raw[offset];
+		int opttype = nh[offset];
 		int optlen;
 
 		if (opttype == type)
@@ -77,7 +78,7 @@
 			optlen = 1;
 			break;
 		default:
-			optlen = skb->nh.raw[offset + 1] + 2;
+			optlen = nh[offset + 1] + 2;
 			if (optlen > len)
 				goto bad;
 			break;
@@ -113,7 +114,7 @@
 {
 	struct sk_buff *skb = *skbp;
 
-	switch ((skb->nh.raw[optoff] & 0xC0) >> 6) {
+	switch ((skb_network_header(skb)[optoff] & 0xC0) >> 6) {
 	case 0: /* ignore */
 		return 1;
 
@@ -141,6 +142,7 @@
 {
 	struct sk_buff *skb = *skbp;
 	struct tlvtype_proc *curr;
+	const unsigned char *nh = skb_network_header(skb);
 	int off = skb->h.raw - skb->nh.raw;
 	int len = ((skb->h.raw[1]+1)<<3);
 
@@ -151,9 +153,9 @@
 	len -= 2;
 
 	while (len > 0) {
-		int optlen = skb->nh.raw[off+1]+2;
+		int optlen = nh[off + 1] + 2;
 
-		switch (skb->nh.raw[off]) {
+		switch (nh[off]) {
 		case IPV6_TLV_PAD0:
 			optlen = 1;
 			break;
@@ -165,7 +167,7 @@
 			if (optlen > len)
 				goto bad;
 			for (curr=procs; curr->type >= 0; curr++) {
-				if (curr->type == skb->nh.raw[off]) {
+				if (curr->type == nh[off]) {
 					/* type specific length/alignment
 					   checks will be performed in the
 					   func(). */
@@ -211,7 +213,7 @@
 	opt->dsthao = opt->dst1;
 	opt->dst1 = 0;
 
-	hao = (struct ipv6_destopt_hao *)(skb->nh.raw + optoff);
+	hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) + optoff);
 
 	if (hao->length != 16) {
 		LIMIT_NETDEBUG(
@@ -244,8 +246,9 @@
 
 		/* update all variable using below by copied skbuff */
 		*skbp = skb = skb2;
-		hao = (struct ipv6_destopt_hao *)(skb2->nh.raw + optoff);
-		ipv6h = (struct ipv6hdr *)skb2->nh.raw;
+		hao = (struct ipv6_destopt_hao *)(skb_network_header(skb2) +
+						  optoff);
+		ipv6h = skb2->nh.ipv6h;
 	}
 
 	if (skb->ip_summed == CHECKSUM_COMPLETE)
@@ -406,7 +409,8 @@
 	default:
 		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
 				 IPSTATS_MIB_INHDRERRORS);
-		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->type) - skb->nh.raw);
+		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
+				  (&hdr->type) - skb_network_header(skb));
 		return -1;
 	}
 
@@ -443,7 +447,7 @@
 		skb->h.raw += (hdr->hdrlen + 1) << 3;
 		opt->dst0 = opt->dst1;
 		opt->dst1 = 0;
-		opt->nhoff = (&hdr->nexthdr) - skb->nh.raw;
+		opt->nhoff = (&hdr->nexthdr) - skb_network_header(skb);
 		return 1;
 	}
 
@@ -452,7 +456,9 @@
 		if (hdr->hdrlen & 0x01) {
 			IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
 					 IPSTATS_MIB_INHDRERRORS);
-			icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->hdrlen) - skb->nh.raw);
+			icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
+					  ((&hdr->hdrlen) -
+					   skb_network_header(skb)));
 			return -1;
 		}
 		break;
@@ -479,7 +485,9 @@
 	if (hdr->segments_left > n) {
 		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
 				 IPSTATS_MIB_INHDRERRORS);
-		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->segments_left) - skb->nh.raw);
+		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
+				  ((&hdr->segments_left) -
+				   skb_network_header(skb)));
 		return -1;
 	}
 
@@ -547,7 +555,7 @@
 	dst_release(xchg(&skb->dst, NULL));
 	ip6_route_input(skb);
 	if (skb->dst->error) {
-		skb_push(skb, skb->data - skb->nh.raw);
+		skb_push(skb, skb->data - skb_network_header(skb));
 		dst_input(skb);
 		return -1;
 	}
@@ -565,7 +573,7 @@
 		goto looped_back;
 	}
 
-	skb_push(skb, skb->data - skb->nh.raw);
+	skb_push(skb, skb->data - skb_network_header(skb));
 	dst_input(skb);
 	return -1;
 }
@@ -656,13 +664,14 @@
 static int ipv6_hop_ra(struct sk_buff **skbp, int optoff)
 {
 	struct sk_buff *skb = *skbp;
+	const unsigned char *nh = skb_network_header(skb);
 
-	if (skb->nh.raw[optoff+1] == 2) {
+	if (nh[optoff + 1] == 2) {
 		IP6CB(skb)->ra = optoff;
 		return 1;
 	}
 	LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_ra: wrong RA length %d\n",
-		       skb->nh.raw[optoff+1]);
+		       nh[optoff + 1]);
 	kfree_skb(skb);
 	return 0;
 }
@@ -672,17 +681,18 @@
 static int ipv6_hop_jumbo(struct sk_buff **skbp, int optoff)
 {
 	struct sk_buff *skb = *skbp;
+	const unsigned char *nh = skb_network_header(skb);
 	u32 pkt_len;
 
-	if (skb->nh.raw[optoff+1] != 4 || (optoff&3) != 2) {
+	if (nh[optoff + 1] != 4 || (optoff & 3) != 2) {
 		LIMIT_NETDEBUG(KERN_DEBUG "ipv6_hop_jumbo: wrong jumbo opt length/alignment %d\n",
-			       skb->nh.raw[optoff+1]);
+			       nh[optoff+1]);
 		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
 				 IPSTATS_MIB_INHDRERRORS);
 		goto drop;
 	}
 
-	pkt_len = ntohl(*(__be32*)(skb->nh.raw+optoff+2));
+	pkt_len = ntohl(*(__be32 *)(nh + optoff + 2));
 	if (pkt_len <= IPV6_MAXPLEN) {
 		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INHDRERRORS);
 		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, optoff+2);
@@ -727,7 +737,7 @@
 	struct inet6_skb_parm *opt = IP6CB(skb);
 
 	/*
-	 * skb->nh.raw is equal to skb->data, and
+	 * skb_network_header(skb) is equal to skb->data, and
 	 * skb->h.raw - skb->nh.raw is always equal to
 	 * sizeof(struct ipv6hdr) by definition of
 	 * hop-by-hop options.
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index aa4a0a5..e5293b3 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -284,7 +284,8 @@
 	if (opt->dsthao) {
 		off = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
 		if (likely(off >= 0)) {
-			hao = (struct ipv6_destopt_hao *)(skb->nh.raw + off);
+			hao = (struct ipv6_destopt_hao *)
+					(skb_network_header(skb) + off);
 			ipv6_addr_copy(&tmp, &iph->saddr);
 			ipv6_addr_copy(&iph->saddr, &hao->addr);
 			ipv6_addr_copy(&hao->addr, &tmp);
diff --git a/net/ipv6/ip6_input.c b/net/ipv6/ip6_input.c
index 61e7a6c..aecc74d 100644
--- a/net/ipv6/ip6_input.c
+++ b/net/ipv6/ip6_input.c
@@ -163,7 +163,7 @@
 	if (!pskb_pull(skb, skb->h.raw - skb->data))
 		goto discard;
 	nhoff = IP6CB(skb)->nhoff;
-	nexthdr = skb->nh.raw[nhoff];
+	nexthdr = skb_network_header(skb)[nhoff];
 
 	raw_sk = sk_head(&raw_v6_htable[nexthdr & (MAX_INET_PROTOS - 1)]);
 	if (raw_sk && !ipv6_raw_deliver(skb, nexthdr))
@@ -181,7 +181,7 @@
 			   indefinitely. */
 			nf_reset(skb);
 
-			skb_postpull_rcsum(skb, skb->nh.raw,
+			skb_postpull_rcsum(skb, skb_network_header(skb),
 					   skb->h.raw - skb->nh.raw);
 			hdr = skb->nh.ipv6h;
 			if (ipv6_addr_is_multicast(&hdr->daddr) &&
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 47d0021..f1dfcc3 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -323,10 +323,11 @@
 	if (nexthdr == IPPROTO_ICMPV6) {
 		struct icmp6hdr *icmp6;
 
-		if (!pskb_may_pull(skb, skb->nh.raw + offset + 1 - skb->data))
+		if (!pskb_may_pull(skb, (skb_network_header(skb) +
+					 offset + 1 - skb->data)))
 			return 0;
 
-		icmp6 = (struct icmp6hdr *)(skb->nh.raw + offset);
+		icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset);
 
 		switch (icmp6->icmp6_type) {
 		case NDISC_ROUTER_SOLICITATION:
@@ -392,7 +393,7 @@
 	 *	that different fragments will go along one path. --ANK
 	 */
 	if (opt->ra) {
-		u8 *ptr = skb->nh.raw + opt->ra;
+		u8 *ptr = skb_network_header(skb) + opt->ra;
 		if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3]))
 			return 0;
 	}
@@ -527,7 +528,7 @@
 {
 	u16 offset = sizeof(struct ipv6hdr);
 	struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1);
-	unsigned int packet_len = skb->tail - skb->nh.raw;
+	unsigned int packet_len = skb->tail - skb_network_header(skb);
 	int found_rhdr = 0;
 	*nexthdr = &skb->nh.ipv6h->nexthdr;
 
@@ -554,7 +555,8 @@
 
 		offset += ipv6_optlen(exthdr);
 		*nexthdr = &exthdr->nexthdr;
-		exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
+		exthdr = (struct ipv6_opt_hdr *)(skb_network_header(skb) +
+						 offset);
 	}
 
 	return offset;
@@ -620,7 +622,7 @@
 		/* BUILD HEADER */
 
 		*prevhdr = NEXTHDR_FRAGMENT;
-		tmp_hdr = kmemdup(skb->nh.raw, hlen, GFP_ATOMIC);
+		tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
 		if (!tmp_hdr) {
 			IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
 			return -ENOMEM;
@@ -630,7 +632,7 @@
 		fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr));
 		__skb_push(skb, hlen);
 		skb_reset_network_header(skb);
-		memcpy(skb->nh.raw, tmp_hdr, hlen);
+		memcpy(skb_network_header(skb), tmp_hdr, hlen);
 
 		ipv6_select_ident(skb, fh);
 		fh->nexthdr = nexthdr;
@@ -654,7 +656,8 @@
 				fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr));
 				__skb_push(frag, hlen);
 				skb_reset_network_header(frag);
-				memcpy(frag->nh.raw, tmp_hdr, hlen);
+				memcpy(skb_network_header(frag), tmp_hdr,
+				       hlen);
 				offset += skb->len - hlen - sizeof(struct frag_hdr);
 				fh->nexthdr = nexthdr;
 				fh->reserved = 0;
@@ -753,7 +756,7 @@
 		/*
 		 *	Copy the packet header into the new buffer.
 		 */
-		memcpy(frag->nh.raw, skb->data, hlen);
+		memcpy(skb_network_header(frag), skb->data, hlen);
 
 		/*
 		 *	Build fragment header.
@@ -1329,7 +1332,7 @@
 	tail_skb = &(skb_shinfo(skb)->frag_list);
 
 	/* move skb->data to ip header from ext header */
-	if (skb->data < skb->nh.raw)
+	if (skb->data < skb_network_header(skb))
 		__skb_pull(skb, skb_network_offset(skb));
 	while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
 		__skb_pull(tmp_skb, skb->h.raw - skb->nh.raw);
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index a1e4f39..aafbdfa 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -995,9 +995,10 @@
 	    !ip6_tnl_xmit_ctl(t) || ip6_tnl_addr_conflict(t, ipv6h))
 		return -1;
 
-	if ((offset = parse_tlv_tnl_enc_lim(skb, skb->nh.raw)) > 0) {
+	offset = parse_tlv_tnl_enc_lim(skb, skb_network_header(skb));
+	if (offset > 0) {
 		struct ipv6_tlv_tnl_enc_lim *tel;
-		tel = (struct ipv6_tlv_tnl_enc_lim *) &skb->nh.raw[offset];
+		tel = (struct ipv6_tlv_tnl_enc_lim *)&skb_network_header(skb)[offset];
 		if (tel->encap_limit == 0) {
 			icmpv6_send(skb, ICMPV6_PARAMPROB,
 				    ICMPV6_HDR_FIELD, offset + 2, skb->dev);
diff --git a/net/ipv6/ipcomp6.c b/net/ipv6/ipcomp6.c
index 5724ba9..3e71d16 100644
--- a/net/ipv6/ipcomp6.c
+++ b/net/ipv6/ipcomp6.c
@@ -166,10 +166,10 @@
 	top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
 
 	ipch = (struct ipv6_comp_hdr *)start;
-	ipch->nexthdr = *skb->nh.raw;
+	ipch->nexthdr = *skb_network_header(skb);
 	ipch->flags = 0;
 	ipch->cpi = htons((u16 )ntohl(x->id.spi));
-	*skb->nh.raw = IPPROTO_COMP;
+	*skb_network_header(skb) = IPPROTO_COMP;
 
 out_ok:
 	return 0;
diff --git a/net/ipv6/mip6.c b/net/ipv6/mip6.c
index 0afcabd..bb40335 100644
--- a/net/ipv6/mip6.c
+++ b/net/ipv6/mip6.c
@@ -99,14 +99,16 @@
 	if (mh->ip6mh_hdrlen < mip6_mh_len(mh->ip6mh_type)) {
 		LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH message too short: %d vs >=%d\n",
 			       mh->ip6mh_hdrlen, mip6_mh_len(mh->ip6mh_type));
-		mip6_param_prob(skb, 0, (&mh->ip6mh_hdrlen) - skb->nh.raw);
+		mip6_param_prob(skb, 0, ((&mh->ip6mh_hdrlen) -
+					 skb_network_header(skb)));
 		return -1;
 	}
 
 	if (mh->ip6mh_proto != IPPROTO_NONE) {
 		LIMIT_NETDEBUG(KERN_DEBUG "mip6: MH invalid payload proto = %d\n",
 			       mh->ip6mh_proto);
-		mip6_param_prob(skb, 0, (&mh->ip6mh_proto) - skb->nh.raw);
+		mip6_param_prob(skb, 0, ((&mh->ip6mh_proto) -
+					 skb_network_header(skb)));
 		return -1;
 	}
 
@@ -152,8 +154,8 @@
 	iph = (struct ipv6hdr *)skb->data;
 	iph->payload_len = htons(skb->len - sizeof(*iph));
 
-	nexthdr = *skb->nh.raw;
-	*skb->nh.raw = IPPROTO_DSTOPTS;
+	nexthdr = *skb_network_header(skb);
+	*skb_network_header(skb) = IPPROTO_DSTOPTS;
 
 	dstopt = (struct ipv6_destopt_hdr *)skb->h.raw;
 	dstopt->nexthdr = nexthdr;
@@ -215,7 +217,8 @@
 	if (likely(opt->dsthao)) {
 		offset = ipv6_find_tlv(skb, opt->dsthao, IPV6_TLV_HAO);
 		if (likely(offset >= 0))
-			hao = (struct ipv6_destopt_hao *)(skb->nh.raw + offset);
+			hao = (struct ipv6_destopt_hao *)
+					(skb_network_header(skb) + offset);
 	}
 
 	skb_get_timestamp(skb, &stamp);
@@ -254,7 +257,8 @@
 {
 	u16 offset = sizeof(struct ipv6hdr);
 	struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1);
-	unsigned int packet_len = skb->tail - skb->nh.raw;
+	const unsigned char *nh = skb_network_header(skb);
+	unsigned int packet_len = skb->tail - nh;
 	int found_rhdr = 0;
 
 	*nexthdr = &skb->nh.ipv6h->nexthdr;
@@ -288,7 +292,7 @@
 
 		offset += ipv6_optlen(exthdr);
 		*nexthdr = &exthdr->nexthdr;
-		exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
+		exthdr = (struct ipv6_opt_hdr *)(nh + offset);
 	}
 
 	return offset;
@@ -361,8 +365,8 @@
 	iph = (struct ipv6hdr *)skb->data;
 	iph->payload_len = htons(skb->len - sizeof(*iph));
 
-	nexthdr = *skb->nh.raw;
-	*skb->nh.raw = IPPROTO_ROUTING;
+	nexthdr = *skb_network_header(skb);
+	*skb_network_header(skb) = IPPROTO_ROUTING;
 
 	rt2 = (struct rt2_hdr *)skb->h.raw;
 	rt2->rt_hdr.nexthdr = nexthdr;
@@ -384,7 +388,8 @@
 {
 	u16 offset = sizeof(struct ipv6hdr);
 	struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1);
-	unsigned int packet_len = skb->tail - skb->nh.raw;
+	const unsigned char *nh = skb_network_header(skb);
+	unsigned int packet_len = skb->tail - nh;
 	int found_rhdr = 0;
 
 	*nexthdr = &skb->nh.ipv6h->nexthdr;
@@ -397,7 +402,7 @@
 		case NEXTHDR_ROUTING:
 			if (offset + 3 <= packet_len) {
 				struct ipv6_rt_hdr *rt;
-				rt = (struct ipv6_rt_hdr *)(skb->nh.raw + offset);
+				rt = (struct ipv6_rt_hdr *)(nh + offset);
 				if (rt->type != 0)
 					return offset;
 			}
@@ -417,7 +422,7 @@
 
 		offset += ipv6_optlen(exthdr);
 		*nexthdr = &exthdr->nexthdr;
-		exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
+		exthdr = (struct ipv6_opt_hdr *)(nh + offset);
 	}
 
 	return offset;
diff --git a/net/ipv6/netfilter/nf_conntrack_reasm.c b/net/ipv6/netfilter/nf_conntrack_reasm.c
index c311b9a..bc1d095 100644
--- a/net/ipv6/netfilter/nf_conntrack_reasm.c
+++ b/net/ipv6/netfilter/nf_conntrack_reasm.c
@@ -408,11 +408,12 @@
 		return -1;
 	}
 
-	if (skb->ip_summed == CHECKSUM_COMPLETE)
+	if (skb->ip_summed == CHECKSUM_COMPLETE) {
+		const unsigned char *nh = skb_network_header(skb);
 		skb->csum = csum_sub(skb->csum,
-				     csum_partial(skb->nh.raw,
-						  (u8*)(fhdr + 1) - skb->nh.raw,
+				     csum_partial(nh, (u8 *)(fhdr + 1) - nh,
 						  0));
+	}
 
 	/* Is this the final fragment? */
 	if (!(fhdr->frag_off & htons(IP6_MF))) {
@@ -583,7 +584,9 @@
 	BUG_TRAP(NFCT_FRAG6_CB(head)->offset == 0);
 
 	/* Unfragmented part is taken from the first segment. */
-	payload_len = (head->data - head->nh.raw) - sizeof(struct ipv6hdr) + fq->len - sizeof(struct frag_hdr);
+	payload_len = ((head->data - skb_network_header(head)) -
+		       sizeof(struct ipv6hdr) + fq->len -
+		       sizeof(struct frag_hdr));
 	if (payload_len > IPV6_MAXPLEN) {
 		DEBUGP("payload len is too large.\n");
 		goto out_oversize;
@@ -624,7 +627,7 @@
 
 	/* We have to remove fragment header from datagram and to relocate
 	 * header in order to calculate ICV correctly. */
-	head->nh.raw[fq->nhoffset] = head->h.raw[0];
+	skb_network_header(head)[fq->nhoffset] = head->h.raw[0];
 	memmove(head->head + sizeof(struct frag_hdr), head->head,
 		(head->data - head->head) - sizeof(struct frag_hdr));
 	head->mac.raw += sizeof(struct frag_hdr);
@@ -632,7 +635,7 @@
 
 	skb_shinfo(head)->frag_list = head->next;
 	head->h.raw = head->data;
-	skb_push(head, head->data - head->nh.raw);
+	skb_push(head, head->data - skb_network_header(head));
 	atomic_sub(head->truesize, &nf_ct_frag6_mem);
 
 	for (fp=head->next; fp; fp = fp->next) {
@@ -653,7 +656,9 @@
 
 	/* Yes, and fold redundant checksum back. 8) */
 	if (head->ip_summed == CHECKSUM_COMPLETE)
-		head->csum = csum_partial(head->nh.raw, head->h.raw-head->nh.raw, head->csum);
+		head->csum = csum_partial(skb_network_header(head),
+					  head->h.raw - head->nh.raw,
+					  head->csum);
 
 	fq->fragments = NULL;
 
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 5f26645..9b2bcde 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -361,7 +361,7 @@
 		skb->ip_summed = CHECKSUM_UNNECESSARY;
 
 	if (skb->ip_summed == CHECKSUM_COMPLETE) {
-		skb_postpull_rcsum(skb, skb->nh.raw,
+		skb_postpull_rcsum(skb, skb_network_header(skb),
 				   skb->h.raw - skb->nh.raw);
 		if (!csum_ipv6_magic(&skb->nh.ipv6h->saddr,
 				     &skb->nh.ipv6h->daddr,
@@ -488,7 +488,8 @@
 		goto out;
 
 	offset = rp->offset;
-	total_len = inet_sk(sk)->cork.length - (skb->nh.raw - skb->data);
+	total_len = inet_sk(sk)->cork.length - (skb_network_header(skb) -
+						skb->data);
 	if (offset >= total_len - 1) {
 		err = -EINVAL;
 		ip6_flush_pending_frames(sk);
diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c
index 1dde449..f85e49a 100644
--- a/net/ipv6/reassembly.c
+++ b/net/ipv6/reassembly.c
@@ -436,13 +436,18 @@
 	if ((unsigned int)end > IPV6_MAXPLEN) {
 		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
 				 IPSTATS_MIB_INHDRERRORS);
-		icmpv6_param_prob(skb,ICMPV6_HDR_FIELD, (u8*)&fhdr->frag_off - skb->nh.raw);
+		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,
+				  ((u8 *)&fhdr->frag_off -
+				   skb_network_header(skb)));
 		return;
 	}
 
-	if (skb->ip_summed == CHECKSUM_COMPLETE)
+	if (skb->ip_summed == CHECKSUM_COMPLETE) {
+		const unsigned char *nh = skb_network_header(skb);
 		skb->csum = csum_sub(skb->csum,
-				     csum_partial(skb->nh.raw, (u8*)(fhdr+1)-skb->nh.raw, 0));
+				     csum_partial(nh, (u8 *)(fhdr + 1) - nh,
+						  0));
+	}
 
 	/* Is this the final fragment? */
 	if (!(fhdr->frag_off & htons(IP6_MF))) {
@@ -605,7 +610,9 @@
 	BUG_TRAP(FRAG6_CB(head)->offset == 0);
 
 	/* Unfragmented part is taken from the first segment. */
-	payload_len = (head->data - head->nh.raw) - sizeof(struct ipv6hdr) + fq->len - sizeof(struct frag_hdr);
+	payload_len = ((head->data - skb_network_header(head)) -
+		       sizeof(struct ipv6hdr) + fq->len -
+		       sizeof(struct frag_hdr));
 	if (payload_len > IPV6_MAXPLEN)
 		goto out_oversize;
 
@@ -639,7 +646,7 @@
 	/* We have to remove fragment header from datagram and to relocate
 	 * header in order to calculate ICV correctly. */
 	nhoff = fq->nhoffset;
-	head->nh.raw[nhoff] = head->h.raw[0];
+	skb_network_header(head)[nhoff] = head->h.raw[0];
 	memmove(head->head + sizeof(struct frag_hdr), head->head,
 		(head->data - head->head) - sizeof(struct frag_hdr));
 	head->mac.raw += sizeof(struct frag_hdr);
@@ -647,7 +654,7 @@
 
 	skb_shinfo(head)->frag_list = head->next;
 	head->h.raw = head->data;
-	skb_push(head, head->data - head->nh.raw);
+	skb_push(head, head->data - skb_network_header(head));
 	atomic_sub(head->truesize, &ip6_frag_mem);
 
 	for (fp=head->next; fp; fp = fp->next) {
@@ -671,7 +678,9 @@
 
 	/* Yes, and fold redundant checksum back. 8) */
 	if (head->ip_summed == CHECKSUM_COMPLETE)
-		head->csum = csum_partial(head->nh.raw, head->h.raw-head->nh.raw, head->csum);
+		head->csum = csum_partial(skb_network_header(head),
+					  head->h.raw - head->nh.raw,
+					  head->csum);
 
 	rcu_read_lock();
 	IP6_INC_STATS_BH(__in6_dev_get(dev), IPSTATS_MIB_REASMOKS);
@@ -725,7 +734,7 @@
 		skb->h.raw += sizeof(struct frag_hdr);
 		IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMOKS);
 
-		IP6CB(skb)->nhoff = (u8*)fhdr - skb->nh.raw;
+		IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb);
 		return 1;
 	}
 
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index 92f9992..80a52ab 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -486,7 +486,9 @@
 			struct sk_buff *pktopts = treq->pktopts;
 			struct inet6_skb_parm *rxopt = IP6CB(pktopts);
 			if (rxopt->srcrt)
-				opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr*)(pktopts->nh.raw + rxopt->srcrt));
+				opt = ipv6_invert_rthdr(sk,
+			  (struct ipv6_rt_hdr *)(skb_network_header(pktopts) +
+						 rxopt->srcrt));
 		}
 
 		if (opt && opt->srcrt) {
@@ -1389,7 +1391,9 @@
 	    opt == NULL && treq->pktopts) {
 		struct inet6_skb_parm *rxopt = IP6CB(treq->pktopts);
 		if (rxopt->srcrt)
-			opt = ipv6_invert_rthdr(sk, (struct ipv6_rt_hdr *)(treq->pktopts->nh.raw + rxopt->srcrt));
+			opt = ipv6_invert_rthdr(sk,
+		   (struct ipv6_rt_hdr *)(skb_network_header(treq->pktopts) +
+					  rxopt->srcrt));
 	}
 
 	if (dst == NULL) {
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 33a1b92..5c929f8 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -28,7 +28,7 @@
 	unsigned int nhoff;
 
 	nhoff = IP6CB(skb)->nhoff;
-	nexthdr = skb->nh.raw[nhoff];
+	nexthdr = skb_network_header(skb)[nhoff];
 
 	seq = 0;
 	if (!spi && (err = xfrm_parse_spi(skb, nexthdr, &spi, &seq)) != 0)
@@ -58,7 +58,7 @@
 		if (nexthdr <= 0)
 			goto drop_unlock;
 
-		skb->nh.raw[nhoff] = nexthdr;
+		skb_network_header(skb)[nhoff] = nexthdr;
 
 		if (x->props.replay_window)
 			xfrm_replay_advance(x, seq);
@@ -113,7 +113,7 @@
 	} else {
 #ifdef CONFIG_NETFILTER
 		skb->nh.ipv6h->payload_len = htons(skb->len);
-		__skb_push(skb, skb->data - skb->nh.raw);
+		__skb_push(skb, skb->data - skb_network_header(skb));
 
 		NF_HOOK(PF_INET6, NF_IP6_PRE_ROUTING, skb, skb->dev, NULL,
 			ip6_rcv_finish);
diff --git a/net/ipv6/xfrm6_mode_beet.c b/net/ipv6/xfrm6_mode_beet.c
index c015bfd..247e2d5 100644
--- a/net/ipv6/xfrm6_mode_beet.c
+++ b/net/ipv6/xfrm6_mode_beet.c
@@ -67,7 +67,7 @@
 		goto out;
 
 	skb_push(skb, size);
-	memmove(skb->data, skb->nh.raw, size);
+	memmove(skb->data, skb_network_header(skb), size);
 	skb_reset_network_header(skb);
 
 	old_mac = skb_mac_header(skb);
diff --git a/net/ipv6/xfrm6_mode_transport.c b/net/ipv6/xfrm6_mode_transport.c
index 3a4b39b..ace0bbf 100644
--- a/net/ipv6/xfrm6_mode_transport.c
+++ b/net/ipv6/xfrm6_mode_transport.c
@@ -53,8 +53,10 @@
 {
 	int ihl = skb->data - skb->h.raw;
 
-	if (skb->h.raw != skb->nh.raw)
-		skb->nh.raw = memmove(skb->h.raw, skb->nh.raw, ihl);
+	if (skb->h.raw != skb->nh.raw) {
+		memmove(skb->h.raw, skb_network_header(skb), ihl);
+		skb->nh.raw = skb->h.raw;
+	}
 	skb->nh.ipv6h->payload_len = htons(skb->len + ihl -
 					   sizeof(struct ipv6hdr));
 	skb->h.raw = skb->data;
diff --git a/net/ipv6/xfrm6_mode_tunnel.c b/net/ipv6/xfrm6_mode_tunnel.c
index 8ce5ef2..498f17b 100644
--- a/net/ipv6/xfrm6_mode_tunnel.c
+++ b/net/ipv6/xfrm6_mode_tunnel.c
@@ -87,9 +87,10 @@
 {
 	int err = -EINVAL;
 	const unsigned char *old_mac;
+	const unsigned char *nh = skb_network_header(skb);
 
-	if (skb->nh.raw[IP6CB(skb)->nhoff] != IPPROTO_IPV6
-	    && skb->nh.raw[IP6CB(skb)->nhoff] != IPPROTO_IPIP)
+	if (nh[IP6CB(skb)->nhoff] != IPPROTO_IPV6 &&
+	    nh[IP6CB(skb)->nhoff] != IPPROTO_IPIP)
 		goto out;
 	if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
 		goto out;
@@ -98,7 +99,8 @@
 	    (err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
 		goto out;
 
-	if (skb->nh.raw[IP6CB(skb)->nhoff] == IPPROTO_IPV6) {
+	nh = skb_network_header(skb);
+	if (nh[IP6CB(skb)->nhoff] == IPPROTO_IPV6) {
 		if (x->props.flags & XFRM_STATE_DECAP_DSCP)
 			ipv6_copy_dscp(skb->nh.ipv6h, skb->h.ipv6h);
 		if (!(x->props.flags & XFRM_STATE_NOECN))
diff --git a/net/ipv6/xfrm6_policy.c b/net/ipv6/xfrm6_policy.c
index d8a585b..cb5a723 100644
--- a/net/ipv6/xfrm6_policy.c
+++ b/net/ipv6/xfrm6_policy.c
@@ -273,14 +273,16 @@
 	u16 offset = skb->h.raw - skb->nh.raw;
 	struct ipv6hdr *hdr = skb->nh.ipv6h;
 	struct ipv6_opt_hdr *exthdr;
-	u8 nexthdr = skb->nh.raw[IP6CB(skb)->nhoff];
+	const unsigned char *nh = skb_network_header(skb);
+	u8 nexthdr = nh[IP6CB(skb)->nhoff];
 
 	memset(fl, 0, sizeof(struct flowi));
 	ipv6_addr_copy(&fl->fl6_dst, &hdr->daddr);
 	ipv6_addr_copy(&fl->fl6_src, &hdr->saddr);
 
-	while (pskb_may_pull(skb, skb->nh.raw + offset + 1 - skb->data)) {
-		exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
+	while (pskb_may_pull(skb, nh + offset + 1 - skb->data)) {
+		nh = skb_network_header(skb);
+		exthdr = (struct ipv6_opt_hdr *)(nh + offset);
 
 		switch (nexthdr) {
 		case NEXTHDR_ROUTING:
@@ -288,7 +290,7 @@
 		case NEXTHDR_DEST:
 			offset += ipv6_optlen(exthdr);
 			nexthdr = exthdr->nexthdr;
-			exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
+			exthdr = (struct ipv6_opt_hdr *)(nh + offset);
 			break;
 
 		case IPPROTO_UDP:
@@ -296,7 +298,7 @@
 		case IPPROTO_TCP:
 		case IPPROTO_SCTP:
 		case IPPROTO_DCCP:
-			if (pskb_may_pull(skb, skb->nh.raw + offset + 4 - skb->data)) {
+			if (pskb_may_pull(skb, nh + offset + 4 - skb->data)) {
 				__be16 *ports = (__be16 *)exthdr;
 
 				fl->fl_ip_sport = ports[0];
@@ -306,7 +308,7 @@
 			return;
 
 		case IPPROTO_ICMPV6:
-			if (pskb_may_pull(skb, skb->nh.raw + offset + 2 - skb->data)) {
+			if (pskb_may_pull(skb, nh + offset + 2 - skb->data)) {
 				u8 *icmp = (u8 *)exthdr;
 
 				fl->fl_icmp_type = icmp[0];
@@ -317,7 +319,7 @@
 
 #ifdef CONFIG_IPV6_MIP6
 		case IPPROTO_MH:
-			if (pskb_may_pull(skb, skb->nh.raw + offset + 3 - skb->data)) {
+			if (pskb_may_pull(skb, nh + offset + 3 - skb->data)) {
 				struct ip6_mh *mh;
 				mh = (struct ip6_mh *)exthdr;