[SK_BUFF]: Convert skb->tail to sk_buff_data_t

So that it is also an offset from skb->head, reduces its size from 8 to 4 bytes
on 64bit architectures, allowing us to combine the 4 bytes hole left by the
layer headers conversion, reducing struct sk_buff size to 256 bytes, i.e. 4
64byte cachelines, and since the sk_buff slab cache is SLAB_HWCACHE_ALIGN...
:-)

Many calculations that previously required that skb->{transport,network,
mac}_header be first converted to a pointer now can be done directly, being
meaningful as offsets or pointers.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/atm/lec.c b/net/atm/lec.c
index d339645..a8c6b28 100644
--- a/net/atm/lec.c
+++ b/net/atm/lec.c
@@ -283,7 +283,7 @@
 	}
 
 	DPRINTK("skbuff head:%lx data:%lx tail:%lx end:%lx\n",
-		(long)skb->head, (long)skb->data, (long)skb->tail,
+		(long)skb->head, (long)skb->data, (long)skb_tail_pointer(skb),
 		(long)skb->end);
 #if defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)
 	if (memcmp(skb->data, bridge_ula_lec, sizeof(bridge_ula_lec)) == 0)
diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index 94f4573..10cc13cf 100644
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -1567,7 +1567,7 @@
 
 	/* Trim FCS */
 	skb->len--; skb->tail--;
-	fcs = *(u8 *) skb->tail;
+	fcs = *(u8 *)skb_tail_pointer(skb);
 
 	if (__check_fcs(skb->data, type, fcs)) {
 		BT_ERR("bad checksum in packet");
diff --git a/net/core/dev.c b/net/core/dev.c
index 6562e57..86dc9f6 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1069,7 +1069,7 @@
 			skb_reset_mac_header(skb2);
 
 			if (skb_network_header(skb2) < skb2->data ||
-			    skb_network_header(skb2) > skb2->tail) {
+			    skb2->network_header > skb2->tail) {
 				if (net_ratelimit())
 					printk(KERN_CRIT "protocol %04x is "
 					       "buggy, dev %s\n",
@@ -1175,7 +1175,7 @@
 	BUG_ON(offset > (int)skb->len);
 	csum = skb_checksum(skb, offset, skb->len-offset, 0);
 
-	offset = skb->tail - skb_transport_header(skb);
+	offset = skb->tail - skb->transport_header;
 	BUG_ON(offset <= 0);
 	BUG_ON(skb->csum_offset + 2 > offset);
 
diff --git a/net/core/filter.c b/net/core/filter.c
index d2358a5..bd903aa 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -46,7 +46,7 @@
 	else if (k >= SKF_LL_OFF)
 		ptr = skb_mac_header(skb) + k - SKF_LL_OFF;
 
-	if (ptr >= skb->head && ptr < skb->tail)
+	if (ptr >= skb->head && ptr < skb_tail_pointer(skb))
 		return ptr;
 	return NULL;
 }
diff --git a/net/core/gen_stats.c b/net/core/gen_stats.c
index 259473d..bcc2559 100644
--- a/net/core/gen_stats.c
+++ b/net/core/gen_stats.c
@@ -61,7 +61,7 @@
 	spin_lock_bh(lock);
 	d->lock = lock;
 	if (type)
-		d->tail = (struct rtattr *) skb->tail;
+		d->tail = (struct rtattr *)skb_tail_pointer(skb);
 	d->skb = skb;
 	d->compat_tc_stats = tc_stats_type;
 	d->compat_xstats = xstats_type;
@@ -212,7 +212,7 @@
 gnet_stats_finish_copy(struct gnet_dump *d)
 {
 	if (d->tail)
-		d->tail->rta_len = d->skb->tail - (u8 *) d->tail;
+		d->tail->rta_len = skb_tail_pointer(d->skb) - (u8 *)d->tail;
 
 	if (d->compat_tc_stats)
 		if (gnet_stats_copy(d, d->compat_tc_stats, &d->tc_stats,
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 9da8357..f9469ea 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -2357,7 +2357,7 @@
 		*vlan_encapsulated_proto = htons(ETH_P_IP);
 	}
 
-	skb_set_network_header(skb, skb->tail - skb->data);
+	skb->network_header = skb->tail;
 	skb->transport_header = skb->network_header + sizeof(struct iphdr);
 	skb_put(skb, sizeof(struct iphdr) + sizeof(struct udphdr));
 
@@ -2696,7 +2696,7 @@
 		*vlan_encapsulated_proto = htons(ETH_P_IPV6);
 	}
 
-	skb_set_network_header(skb, skb->tail - skb->data);
+	skb->network_header = skb->tail;
 	skb->transport_header = skb->network_header + sizeof(struct ipv6hdr);
 	skb_put(skb, sizeof(struct ipv6hdr) + sizeof(struct udphdr));
 
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index a48b086..ddcbc4d 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -87,8 +87,9 @@
 void skb_over_panic(struct sk_buff *skb, int sz, void *here)
 {
 	printk(KERN_EMERG "skb_over_panic: text:%p len:%d put:%d head:%p "
-			  "data:%p tail:%p end:%p dev:%s\n",
-	       here, skb->len, sz, skb->head, skb->data, skb->tail, skb->end,
+			  "data:%p tail:%#lx end:%p dev:%s\n",
+	       here, skb->len, sz, skb->head, skb->data,
+	       (unsigned long)skb->tail, skb->end,
 	       skb->dev ? skb->dev->name : "<NULL>");
 	BUG();
 }
@@ -105,8 +106,9 @@
 void skb_under_panic(struct sk_buff *skb, int sz, void *here)
 {
 	printk(KERN_EMERG "skb_under_panic: text:%p len:%d put:%d head:%p "
-			  "data:%p tail:%p end:%p dev:%s\n",
-	       here, skb->len, sz, skb->head, skb->data, skb->tail, skb->end,
+			  "data:%p tail:%#lx end:%p dev:%s\n",
+	       here, skb->len, sz, skb->head, skb->data,
+	       (unsigned long)skb->tail, skb->end,
 	       skb->dev ? skb->dev->name : "<NULL>");
 	BUG();
 }
@@ -167,7 +169,7 @@
 	atomic_set(&skb->users, 1);
 	skb->head = data;
 	skb->data = data;
-	skb->tail = data;
+	skb_reset_tail_pointer(skb);
 	skb->end  = data + size;
 	/* make sure we initialize shinfo sequentially */
 	shinfo = skb_shinfo(skb);
@@ -629,7 +631,12 @@
 
 	/* Copy only real data... and, alas, header. This should be
 	 * optimized for the cases when header is void. */
-	memcpy(data + nhead, skb->head, skb->tail - skb->head);
+	memcpy(data + nhead, skb->head,
+		skb->tail
+#ifndef NET_SKBUFF_DATA_USES_OFFSET
+		- skb->head
+#endif
+		);
 	memcpy(data + size, skb->end, sizeof(struct skb_shared_info));
 
 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
@@ -645,9 +652,9 @@
 	skb->head     = data;
 	skb->end      = data + size;
 	skb->data    += off;
-	skb->tail    += off;
 #ifndef NET_SKBUFF_DATA_USES_OFFSET
-	/* {transport,network,mac}_header are relative to skb->head */
+	/* {transport,network,mac}_header and tail are relative to skb->head */
+	skb->tail	      += off;
 	skb->transport_header += off;
 	skb->network_header   += off;
 	skb->mac_header	      += off;
@@ -762,7 +769,7 @@
 		return 0;
 	}
 
-	ntail = skb->data_len + pad - (skb->end - skb->tail);
+	ntail = skb->data_len + pad - (skb->end - skb_tail_pointer(skb));
 	if (likely(skb_cloned(skb) || ntail > 0)) {
 		err = pskb_expand_head(skb, 0, ntail, GFP_ATOMIC);
 		if (unlikely(err))
@@ -863,7 +870,7 @@
 	} else {
 		skb->len       = len;
 		skb->data_len  = 0;
-		skb->tail      = skb->data + len;
+		skb_set_tail_pointer(skb, len);
 	}
 
 	return 0;
@@ -900,7 +907,7 @@
 	 * plus 128 bytes for future expansions. If we have enough
 	 * room at tail, reallocate without expansion only if skb is cloned.
 	 */
-	int i, k, eat = (skb->tail + delta) - skb->end;
+	int i, k, eat = (skb_tail_pointer(skb) + delta) - skb->end;
 
 	if (eat > 0 || skb_cloned(skb)) {
 		if (pskb_expand_head(skb, 0, eat > 0 ? eat + 128 : 0,
@@ -908,7 +915,7 @@
 			return NULL;
 	}
 
-	if (skb_copy_bits(skb, skb_headlen(skb), skb->tail, delta))
+	if (skb_copy_bits(skb, skb_headlen(skb), skb_tail_pointer(skb), delta))
 		BUG();
 
 	/* Optimization: no fragments, no reasons to preestimate
@@ -1004,7 +1011,7 @@
 	skb->tail     += delta;
 	skb->data_len -= delta;
 
-	return skb->tail;
+	return skb_tail_pointer(skb);
 }
 
 /* Copy some data bits from skb to kernel buffer. */
@@ -1539,7 +1546,7 @@
 	skb1->len		   += skb1->data_len;
 	skb->data_len		   = 0;
 	skb->len		   = len;
-	skb->tail		   = skb->data + len;
+	skb_set_tail_pointer(skb, len);
 }
 
 static inline void skb_split_no_header(struct sk_buff *skb,
diff --git a/net/core/wireless.c b/net/core/wireless.c
index 7c6a5db..4a777b6 100644
--- a/net/core/wireless.c
+++ b/net/core/wireless.c
@@ -1938,7 +1938,7 @@
 {
 	struct ifinfomsg *r;
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
+	unsigned char	 *b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_PUT(skb, 0, 0, type, sizeof(*r));
 	r = NLMSG_DATA(nlh);
@@ -1952,7 +1952,7 @@
 	/* Add the wireless events in the netlink packet */
 	RTA_PUT(skb, IFLA_WIRELESS, event_len, event);
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
diff --git a/net/decnet/dn_nsp_out.c b/net/decnet/dn_nsp_out.c
index 84b8c5b..7404653 100644
--- a/net/decnet/dn_nsp_out.c
+++ b/net/decnet/dn_nsp_out.c
@@ -681,8 +681,10 @@
 	if (scp->peer.sdn_objnum)
 		type = 0;
 
-	skb_put(skb, dn_sockaddr2username(&scp->peer, skb->tail, type));
-	skb_put(skb, dn_sockaddr2username(&scp->addr, skb->tail, 2));
+	skb_put(skb, dn_sockaddr2username(&scp->peer,
+					  skb_tail_pointer(skb), type));
+	skb_put(skb, dn_sockaddr2username(&scp->addr,
+					  skb_tail_pointer(skb), 2));
 
 	menuver = DN_MENUVER_ACC | DN_MENUVER_USR;
 	if (scp->peer.sdn_flags & SDF_PROXY)
diff --git a/net/decnet/dn_route.c b/net/decnet/dn_route.c
index bb73bf1..9678b09 100644
--- a/net/decnet/dn_route.c
+++ b/net/decnet/dn_route.c
@@ -1468,7 +1468,7 @@
 	struct dn_route *rt = (struct dn_route *)skb->dst;
 	struct rtmsg *r;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	long expires;
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*r), flags);
@@ -1509,7 +1509,7 @@
 	if (rt->fl.iif)
 		RTA_PUT(skb, RTA_IIF, sizeof(int), &rt->fl.iif);
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
diff --git a/net/decnet/dn_table.c b/net/decnet/dn_table.c
index 780a141..544c455 100644
--- a/net/decnet/dn_table.c
+++ b/net/decnet/dn_table.c
@@ -295,7 +295,7 @@
 {
 	struct rtmsg *rtm;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*rtm), flags);
 	rtm = NLMSG_DATA(nlh);
@@ -337,13 +337,13 @@
 			nhp->rtnh_ifindex = nh->nh_oif;
 			if (nh->nh_gw)
 				RTA_PUT(skb, RTA_GATEWAY, 2, &nh->nh_gw);
-			nhp->rtnh_len = skb->tail - (unsigned char *)nhp;
+			nhp->rtnh_len = skb_tail_pointer(skb) - (unsigned char *)nhp;
 		} endfor_nexthops(fi);
 		mp_head->rta_type = RTA_MULTIPATH;
-		mp_head->rta_len = skb->tail - (u8*)mp_head;
+		mp_head->rta_len = skb_tail_pointer(skb) - (u8 *)mp_head;
 	}
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 
diff --git a/net/decnet/netfilter/dn_rtmsg.c b/net/decnet/netfilter/dn_rtmsg.c
index 0e62def..ceefd9d 100644
--- a/net/decnet/netfilter/dn_rtmsg.c
+++ b/net/decnet/netfilter/dn_rtmsg.c
@@ -33,7 +33,7 @@
 {
 	struct sk_buff *skb = NULL;
 	size_t size;
-	unsigned char *old_tail;
+	sk_buff_data_t old_tail;
 	struct nlmsghdr *nlh;
 	unsigned char *ptr;
 	struct nf_dn_rtmsg *rtm;
diff --git a/net/econet/af_econet.c b/net/econet/af_econet.c
index 78993da..b5524f3 100644
--- a/net/econet/af_econet.c
+++ b/net/econet/af_econet.c
@@ -366,7 +366,7 @@
 			fh->cb = cb;
 			fh->port = port;
 			if (sock->type != SOCK_DGRAM) {
-				skb->tail = skb->data;
+				skb_reset_tail_pointer(skb);
 				skb->len = 0;
 			} else if (res < 0)
 				goto out_free;
diff --git a/net/ieee80211/ieee80211_rx.c b/net/ieee80211/ieee80211_rx.c
index 59a765c..2b85494 100644
--- a/net/ieee80211/ieee80211_rx.c
+++ b/net/ieee80211/ieee80211_rx.c
@@ -595,7 +595,7 @@
 		if (frag != 0)
 			flen -= hdrlen;
 
-		if (frag_skb->tail + flen > frag_skb->end) {
+		if (skb_tail_pointer(frag_skb) + flen > frag_skb->end) {
 			printk(KERN_WARNING "%s: host decrypted and "
 			       "reassembled frame did not fit skb\n",
 			       dev->name);
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index de019f9..5e56139 100644
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -21,6 +21,7 @@
 	struct blkcipher_desc desc;
 	struct esp_data *esp;
 	struct sk_buff *trailer;
+	u8 *tail;
 	int blksize;
 	int clen;
 	int alen;
@@ -49,12 +50,13 @@
 		goto error;
 
 	/* Fill padding... */
+	tail = skb_tail_pointer(trailer);
 	do {
 		int i;
 		for (i=0; i<clen-skb->len - 2; i++)
-			*(u8*)(trailer->tail + i) = i+1;
+			tail[i] = i + 1;
 	} while (0);
-	*(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2;
+	tail[clen - skb->len - 2] = (clen - skb->len) - 2;
 	pskb_put(skb, trailer, clen - skb->len);
 
 	__skb_push(skb, skb->data - skb_network_header(skb));
@@ -62,7 +64,7 @@
 	esph = (struct ip_esp_hdr *)(skb_network_header(skb) +
 				     top_iph->ihl * 4);
 	top_iph->tot_len = htons(skb->len + alen);
-	*(u8*)(trailer->tail - 1) = top_iph->protocol;
+	*(skb_tail_pointer(skb) - 1) = top_iph->protocol;
 
 	/* this is non-NULL only with UDP Encapsulation */
 	if (x->encap) {
diff --git a/net/ipv4/icmp.c b/net/ipv4/icmp.c
index 8372f8b..d38cbba 100644
--- a/net/ipv4/icmp.c
+++ b/net/ipv4/icmp.c
@@ -450,7 +450,8 @@
 	 */
 	iph = ip_hdr(skb_in);
 
-	if ((u8 *)iph < skb_in->head || (u8 *)(iph + 1) > skb_in->tail)
+	if ((u8 *)iph < skb_in->head ||
+	    (skb_in->network_header + sizeof(*iph)) > skb_in->tail)
 		goto out;
 
 	/*
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 1fc637f..2506021 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -348,8 +348,8 @@
 {
 	struct iphdr *pip = ip_hdr(skb);
 	struct igmphdr *pig = igmp_hdr(skb);
-	const int iplen = skb->tail - skb_network_header(skb);
-	const int igmplen = skb->tail - skb_transport_header(skb);
+	const int iplen = skb->tail - skb->network_header;
+	const int igmplen = skb->tail - skb->transport_header;
 
 	pip->tot_len = htons(iplen);
 	ip_send_check(pip);
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index 5df71cd..37362cd 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -60,7 +60,7 @@
 	struct nlmsghdr  *nlh;
 	void *info = NULL;
 	struct inet_diag_meminfo  *minfo = NULL;
-	unsigned char	 *b = skb->tail;
+	unsigned char	 *b = skb_tail_pointer(skb);
 	const struct inet_diag_handler *handler;
 
 	handler = inet_diag_table[unlh->nlmsg_type];
@@ -147,7 +147,7 @@
 	    icsk->icsk_ca_ops && icsk->icsk_ca_ops->get_info)
 		icsk->icsk_ca_ops->get_info(sk, ext, skb);
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
@@ -163,7 +163,7 @@
 {
 	long tmo;
 	struct inet_diag_msg *r;
-	const unsigned char *previous_tail = skb->tail;
+	const unsigned char *previous_tail = skb_tail_pointer(skb);
 	struct nlmsghdr *nlh = NLMSG_PUT(skb, pid, seq,
 					 unlh->nlmsg_type, sizeof(*r));
 
@@ -205,7 +205,7 @@
 			       &tw6->tw_v6_daddr);
 	}
 #endif
-	nlh->nlmsg_len = skb->tail - previous_tail;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - previous_tail;
 	return skb->len;
 nlmsg_failure:
 	skb_trim(skb, previous_tail - skb->data);
@@ -535,7 +535,7 @@
 {
 	const struct inet_request_sock *ireq = inet_rsk(req);
 	struct inet_sock *inet = inet_sk(sk);
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct inet_diag_msg *r;
 	struct nlmsghdr *nlh;
 	long tmo;
@@ -574,7 +574,7 @@
 			       &inet6_rsk(req)->rmt_addr);
 	}
 #endif
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 
 	return skb->len;
 
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index fcb35cd..c199d23 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -316,7 +316,7 @@
 	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 	serr->port = port;
 
-	__skb_pull(skb, skb->tail - skb->data);
+	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 	skb_reset_transport_header(skb);
 
 	if (sock_queue_err_skb(sk, skb))
diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index 50d0b301..ea0a491 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -513,7 +513,8 @@
 			struct nlmsghdr *nlh = (struct nlmsghdr *)skb_pull(skb, sizeof(struct iphdr));
 
 			if (ipmr_fill_mroute(skb, c, NLMSG_DATA(nlh)) > 0) {
-				nlh->nlmsg_len = skb->tail - (u8*)nlh;
+				nlh->nlmsg_len = (skb_tail_pointer(skb) -
+						  (u8 *)nlh);
 			} else {
 				nlh->nlmsg_type = NLMSG_ERROR;
 				nlh->nlmsg_len = NLMSG_LENGTH(sizeof(struct nlmsgerr));
@@ -580,7 +581,7 @@
 	 *	Copy the IP header
 	 */
 
-	skb_set_network_header(skb, skb->tail - skb->data);
+	skb->network_header = skb->tail;
 	skb_put(skb, ihl);
 	memcpy(skb->data,pkt->data,ihl);
 	ip_hdr(skb)->protocol = 0;			/* Flag to the kernel this is a route add */
@@ -1544,7 +1545,7 @@
 	int ct;
 	struct rtnexthop *nhp;
 	struct net_device *dev = vif_table[c->mfc_parent].dev;
-	u8 *b = skb->tail;
+	u8 *b = skb_tail_pointer(skb);
 	struct rtattr *mp_head;
 
 	if (dev)
@@ -1564,7 +1565,7 @@
 		}
 	}
 	mp_head->rta_type = RTA_MULTIPATH;
-	mp_head->rta_len = skb->tail - (u8*)mp_head;
+	mp_head->rta_len = skb_tail_pointer(skb) - (u8 *)mp_head;
 	rtm->rtm_type = RTN_MULTICAST;
 	return 1;
 
diff --git a/net/ipv4/ipvs/ip_vs_ftp.c b/net/ipv4/ipvs/ip_vs_ftp.c
index 25bd689..344ddbb 100644
--- a/net/ipv4/ipvs/ip_vs_ftp.c
+++ b/net/ipv4/ipvs/ip_vs_ftp.c
@@ -162,7 +162,7 @@
 		iph = ip_hdr(*pskb);
 		th = (struct tcphdr *)&(((char *)iph)[iph->ihl*4]);
 		data = (char *)th + (th->doff << 2);
-		data_limit = (*pskb)->tail;
+		data_limit = skb_tail_pointer(*pskb);
 
 		if (ip_vs_ftp_get_addrport(data, data_limit,
 					   SERVER_STRING,
@@ -269,7 +269,7 @@
 	   the length of the header in 32-bit multiples, it is accurate
 	   to calculate data address by th+HLEN*4 */
 	data = data_start = (char *)th + (th->doff << 2);
-	data_limit = (*pskb)->tail;
+	data_limit = skb_tail_pointer(*pskb);
 
 	while (data <= data_limit - 6) {
 		if (strnicmp(data, "PASV\r\n", 6) == 0) {
diff --git a/net/ipv4/netfilter/arpt_mangle.c b/net/ipv4/netfilter/arpt_mangle.c
index b4450f1..6298d40 100644
--- a/net/ipv4/netfilter/arpt_mangle.c
+++ b/net/ipv4/netfilter/arpt_mangle.c
@@ -37,28 +37,28 @@
 	/* We assume that pln and hln were checked in the match */
 	if (mangle->flags & ARPT_MANGLE_SDEV) {
 		if (ARPT_DEV_ADDR_LEN_MAX < hln ||
-		   (arpptr + hln > (**pskb).tail))
+		   (arpptr + hln > skb_tail_pointer(*pskb)))
 			return NF_DROP;
 		memcpy(arpptr, mangle->src_devaddr, hln);
 	}
 	arpptr += hln;
 	if (mangle->flags & ARPT_MANGLE_SIP) {
 		if (ARPT_MANGLE_ADDR_LEN_MAX < pln ||
-		   (arpptr + pln > (**pskb).tail))
+		   (arpptr + pln > skb_tail_pointer(*pskb)))
 			return NF_DROP;
 		memcpy(arpptr, &mangle->u_s.src_ip, pln);
 	}
 	arpptr += pln;
 	if (mangle->flags & ARPT_MANGLE_TDEV) {
 		if (ARPT_DEV_ADDR_LEN_MAX < hln ||
-		   (arpptr + hln > (**pskb).tail))
+		   (arpptr + hln > skb_tail_pointer(*pskb)))
 			return NF_DROP;
 		memcpy(arpptr, mangle->tgt_devaddr, hln);
 	}
 	arpptr += hln;
 	if (mangle->flags & ARPT_MANGLE_TIP) {
 		if (ARPT_MANGLE_ADDR_LEN_MAX < pln ||
-		   (arpptr + pln > (**pskb).tail))
+		   (arpptr + pln > skb_tail_pointer(*pskb)))
 			return NF_DROP;
 		memcpy(arpptr, &mangle->u_t.tgt_ip, pln);
 	}
diff --git a/net/ipv4/netfilter/ip_queue.c b/net/ipv4/netfilter/ip_queue.c
index 5842f1a..15e0d20 100644
--- a/net/ipv4/netfilter/ip_queue.c
+++ b/net/ipv4/netfilter/ip_queue.c
@@ -191,7 +191,7 @@
 static struct sk_buff *
 ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
 {
-	unsigned char *old_tail;
+	sk_buff_data_t old_tail;
 	size_t size = 0;
 	size_t data_len = 0;
 	struct sk_buff *skb;
@@ -235,7 +235,7 @@
 	if (!skb)
 		goto nlmsg_failure;
 
-	old_tail= skb->tail;
+	old_tail = skb->tail;
 	nlh = NLMSG_PUT(skb, 0, 0, IPQM_PACKET, size - sizeof(*nlh));
 	pmsg = NLMSG_DATA(nlh);
 	memset(pmsg, 0, sizeof(*pmsg));
diff --git a/net/ipv4/netfilter/nf_nat_helper.c b/net/ipv4/netfilter/nf_nat_helper.c
index c2c92ff..8a40fbe 100644
--- a/net/ipv4/netfilter/nf_nat_helper.c
+++ b/net/ipv4/netfilter/nf_nat_helper.c
@@ -92,7 +92,8 @@
 	/* move post-replacement */
 	memmove(data + match_offset + rep_len,
 		data + match_offset + match_len,
-		skb->tail - (data + match_offset + match_len));
+		skb->tail - (skb->network_header + dataoff +
+			     match_offset + match_len));
 
 	/* insert data from buffer */
 	memcpy(data + match_offset, rep_buffer, rep_len);
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index 2b214cc..18a09a7 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2231,7 +2231,7 @@
 		th->cwr = 0;
 	} while (skb->next);
 
-	delta = htonl(oldlen + (skb->tail - skb_transport_header(skb)) +
+	delta = htonl(oldlen + (skb->tail - skb->transport_header) +
 		      skb->data_len);
 	th->check = ~csum_fold((__force __wsum)((__force u32)th->check +
 				(__force u32)delta));
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 29c53fb..c22cdcd 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -733,7 +733,7 @@
 	}
 	skb_shinfo(skb)->nr_frags = k;
 
-	skb->tail = skb->data;
+	skb_reset_tail_pointer(skb);
 	skb->data_len -= len;
 	skb->len = skb->data_len;
 }
diff --git a/net/ipv6/datagram.c b/net/ipv6/datagram.c
index f16f4f0..4a355fe 100644
--- a/net/ipv6/datagram.c
+++ b/net/ipv6/datagram.c
@@ -268,7 +268,7 @@
 	serr->addr_offset = (u8 *)&iph->daddr - skb_network_header(skb);
 	serr->port = fl->fl_ip_dport;
 
-	__skb_pull(skb, skb->tail - skb->data);
+	__skb_pull(skb, skb_tail_pointer(skb) - skb->data);
 	skb_reset_transport_header(skb);
 
 	if (sock_queue_err_skb(sk, skb))
diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index 7fdf84d..b8e8914 100644
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -51,6 +51,7 @@
 	int clen;
 	int alen;
 	int nfrags;
+	u8 *tail;
 	struct esp_data *esp = x->data;
 	int hdr_len = (skb_transport_offset(skb) +
 		       sizeof(*esph) + esp->conf.ivlen);
@@ -78,18 +79,19 @@
 	}
 
 	/* Fill padding... */
+	tail = skb_tail_pointer(trailer);
 	do {
 		int i;
 		for (i=0; i<clen-skb->len - 2; i++)
-			*(u8*)(trailer->tail + i) = i+1;
+			tail[i] = i + 1;
 	} while (0);
-	*(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2;
+	tail[clen-skb->len - 2] = (clen - skb->len) - 2;
 	pskb_put(skb, trailer, clen - skb->len);
 
 	top_iph = (struct ipv6hdr *)__skb_push(skb, hdr_len);
 	esph = (struct ipv6_esp_hdr *)skb_transport_header(skb);
 	top_iph->payload_len = htons(skb->len + alen - sizeof(*top_iph));
-	*(u8 *)(trailer->tail - 1) = *skb_network_header(skb);
+	*(skb_tail_pointer(skb) - 1) = *skb_network_header(skb);
 	*skb_network_header(skb) = IPPROTO_ESP;
 
 	esph->spi = x->id.spi;
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index a6a275d..275d2e8 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -51,7 +51,7 @@
 int ipv6_find_tlv(struct sk_buff *skb, int offset, int type)
 {
 	const unsigned char *nh = skb_network_header(skb);
-	int packet_len = skb->tail - nh;
+	int packet_len = skb->tail - skb->network_header;
 	struct ipv6_opt_hdr *hdr;
 	int len;
 
diff --git a/net/ipv6/icmp.c b/net/ipv6/icmp.c
index d3edc3c..e94992a 100644
--- a/net/ipv6/icmp.c
+++ b/net/ipv6/icmp.c
@@ -317,7 +317,8 @@
 	int hlimit, tclass;
 	int err = 0;
 
-	if ((u8*)hdr < skb->head || (u8*)(hdr+1) > skb->tail)
+	if ((u8 *)hdr < skb->head ||
+	    (skb->network_header + sizeof(*hdr)) > skb->tail)
 		return;
 
 	/*
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index b2c092c..e2b8db6 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -514,7 +514,7 @@
 	u16 offset = sizeof(struct ipv6hdr);
 	struct ipv6_opt_hdr *exthdr =
 				(struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
-	unsigned int packet_len = skb->tail - skb_network_header(skb);
+	unsigned int packet_len = skb->tail - skb->network_header;
 	int found_rhdr = 0;
 	*nexthdr = &ipv6_hdr(skb)->nexthdr;
 
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index 4c45bcc..6c27589 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -1423,7 +1423,7 @@
 
 	memcpy(skb_put(skb, sizeof(ra)), ra, sizeof(ra));
 
-	skb_set_transport_header(skb, skb->tail - skb->data);
+	skb_set_transport_header(skb, skb_tail_pointer(skb) - skb->data);
 	skb_put(skb, sizeof(*pmr));
 	pmr = (struct mld2_report *)skb_transport_header(skb);
 	pmr->type = ICMPV6_MLD2_REPORT;
@@ -1468,8 +1468,8 @@
 	int err;
 
 	IP6_INC_STATS(idev, IPSTATS_MIB_OUTREQUESTS);
-	payload_len = skb->tail - skb_network_header(skb) - sizeof(*pip6);
-	mldlen = skb->tail - skb_transport_header(skb);
+	payload_len = (skb->tail - skb->network_header) - sizeof(*pip6);
+	mldlen = skb->tail - skb->transport_header;
 	pip6->payload_len = htons(payload_len);
 
 	pmr->csum = csum_ipv6_magic(&pip6->saddr, &pip6->daddr, mldlen,
diff --git a/net/ipv6/mip6.c b/net/ipv6/mip6.c
index f0288e9..6ed763e 100644
--- a/net/ipv6/mip6.c
+++ b/net/ipv6/mip6.c
@@ -260,7 +260,7 @@
 	struct ipv6_opt_hdr *exthdr =
 				   (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
 	const unsigned char *nh = skb_network_header(skb);
-	unsigned int packet_len = skb->tail - nh;
+	unsigned int packet_len = skb->tail - skb->network_header;
 	int found_rhdr = 0;
 
 	*nexthdr = &ipv6_hdr(skb)->nexthdr;
@@ -392,7 +392,7 @@
 	struct ipv6_opt_hdr *exthdr =
 				   (struct ipv6_opt_hdr *)(ipv6_hdr(skb) + 1);
 	const unsigned char *nh = skb_network_header(skb);
-	unsigned int packet_len = skb->tail - nh;
+	unsigned int packet_len = skb->tail - skb->network_header;
 	int found_rhdr = 0;
 
 	*nexthdr = &ipv6_hdr(skb)->nexthdr;
diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c
index f8e6197..b1cf708 100644
--- a/net/ipv6/ndisc.c
+++ b/net/ipv6/ndisc.c
@@ -492,7 +492,7 @@
 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
 	ip6_nd_hdr(sk, skb, dev, src_addr, daddr, IPPROTO_ICMPV6, len);
 
-	skb_set_transport_header(skb, skb->tail - skb->data);
+	skb->transport_header = skb->tail;
 	skb_put(skb, len);
 	msg = (struct nd_msg *)skb_transport_header(skb);
 
@@ -584,7 +584,7 @@
 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
 	ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
 
-	skb_set_transport_header(skb, skb->tail - skb->data);
+	skb->transport_header = skb->tail;
 	skb_put(skb, len);
 	msg = (struct nd_msg *)skb_transport_header(skb);
 	msg->icmph.icmp6_type = NDISC_NEIGHBOUR_SOLICITATION;
@@ -685,7 +685,7 @@
 	skb_reserve(skb, LL_RESERVED_SPACE(dev));
 	ip6_nd_hdr(sk, skb, dev, saddr, daddr, IPPROTO_ICMPV6, len);
 
-	skb_set_transport_header(skb, skb->tail - skb->data);
+	skb->transport_header = skb->tail;
 	skb_put(skb, len);
 	hdr = icmp6_hdr(skb);
 	hdr->icmp6_type = NDISC_ROUTER_SOLICITATION;
@@ -767,7 +767,8 @@
 	struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
 	struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
 	u8 *lladdr = NULL;
-	u32 ndoptlen = skb->tail - msg->opt;
+	u32 ndoptlen = skb->tail - (skb->transport_header +
+				    offsetof(struct nd_msg, opt));
 	struct ndisc_options ndopts;
 	struct net_device *dev = skb->dev;
 	struct inet6_ifaddr *ifp;
@@ -945,7 +946,8 @@
 	struct in6_addr *saddr = &ipv6_hdr(skb)->saddr;
 	struct in6_addr *daddr = &ipv6_hdr(skb)->daddr;
 	u8 *lladdr = NULL;
-	u32 ndoptlen = skb->tail - msg->opt;
+	u32 ndoptlen = skb->tail - (skb->transport_header +
+				    offsetof(struct nd_msg, opt));
 	struct ndisc_options ndopts;
 	struct net_device *dev = skb->dev;
 	struct inet6_ifaddr *ifp;
@@ -1111,8 +1113,7 @@
 
 	__u8 * opt = (__u8 *)(ra_msg + 1);
 
-	optlen = (skb->tail - skb_transport_header(skb)) -
-		  sizeof(struct ra_msg);
+	optlen = (skb->tail - skb->transport_header) - sizeof(struct ra_msg);
 
 	if (!(ipv6_addr_type(&ipv6_hdr(skb)->saddr) & IPV6_ADDR_LINKLOCAL)) {
 		ND_PRINTK2(KERN_WARNING
@@ -1361,7 +1362,7 @@
 		return;
 	}
 
-	optlen = skb->tail - skb_transport_header(skb);
+	optlen = skb->tail - skb->transport_header;
 	optlen -= sizeof(struct icmp6hdr) + 2 * sizeof(struct in6_addr);
 
 	if (optlen < 0) {
@@ -1522,7 +1523,7 @@
 	ip6_nd_hdr(sk, buff, dev, &saddr_buf, &ipv6_hdr(skb)->saddr,
 		   IPPROTO_ICMPV6, len);
 
-	skb_set_transport_header(buff, buff->tail - buff->data);
+	skb_set_transport_header(buff, skb_tail_pointer(buff) - buff->data);
 	skb_put(buff, len);
 	icmph = icmp6_hdr(buff);
 
diff --git a/net/ipv6/netfilter/ip6_queue.c b/net/ipv6/netfilter/ip6_queue.c
index 66a2c41..5cfce21 100644
--- a/net/ipv6/netfilter/ip6_queue.c
+++ b/net/ipv6/netfilter/ip6_queue.c
@@ -189,7 +189,7 @@
 static struct sk_buff *
 ipq_build_packet_message(struct ipq_queue_entry *entry, int *errp)
 {
-	unsigned char *old_tail;
+	sk_buff_data_t old_tail;
 	size_t size = 0;
 	size_t data_len = 0;
 	struct sk_buff *skb;
@@ -233,7 +233,7 @@
 	if (!skb)
 		goto nlmsg_failure;
 
-	old_tail= skb->tail;
+	old_tail = skb->tail;
 	nlh = NLMSG_PUT(skb, 0, 0, IPQM_PACKET, size - sizeof(*nlh));
 	pmsg = NLMSG_DATA(nlh);
 	memset(pmsg, 0, sizeof(*pmsg));
diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 8705f6a..2b3be68 100644
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -1077,7 +1077,7 @@
 			spin_lock_bh(&sk->sk_receive_queue.lock);
 			skb = skb_peek(&sk->sk_receive_queue);
 			if (skb != NULL)
-				amount = skb->tail - skb_transport_header(skb);
+				amount = skb->tail - skb->transport_header;
 			spin_unlock_bh(&sk->sk_receive_queue.lock);
 			return put_user(amount, (int __user *)arg);
 		}
diff --git a/net/irda/ircomm/ircomm_param.c b/net/irda/ircomm/ircomm_param.c
index 01d7c9c..e5e4792 100644
--- a/net/irda/ircomm/ircomm_param.c
+++ b/net/irda/ircomm/ircomm_param.c
@@ -133,8 +133,8 @@
 	 * Inserting is a little bit tricky since we don't know how much
 	 * room we will need. But this should hopefully work OK
 	 */
-	count = irda_param_insert(self, pi, skb->tail, skb_tailroom(skb),
-				  &ircomm_param_info);
+	count = irda_param_insert(self, pi, skb_tail_pointer(skb),
+				  skb_tailroom(skb), &ircomm_param_info);
 	if (count < 0) {
 		IRDA_WARNING("%s(), no room for parameter!\n", __FUNCTION__);
 		spin_unlock_irqrestore(&self->spinlock, flags);
diff --git a/net/irda/irlan/irlan_common.c b/net/irda/irlan/irlan_common.c
index fcf9d65..ed69773 100644
--- a/net/irda/irlan/irlan_common.c
+++ b/net/irda/irlan/irlan_common.c
@@ -1039,7 +1039,7 @@
 	}
 
 	/* Insert at end of sk-buffer */
-	frame = skb->tail;
+	frame = skb_tail_pointer(skb);
 
 	/* Make space for data */
 	if (skb_tailroom(skb) < (param_len+value_len+3)) {
diff --git a/net/irda/qos.c b/net/irda/qos.c
index 349012c..aeb18cf 100644
--- a/net/irda/qos.c
+++ b/net/irda/qos.c
@@ -469,49 +469,49 @@
 	int ret;
 
 	/* Insert data rate */
-	ret = irda_param_insert(self, PI_BAUD_RATE, skb->tail,
+	ret = irda_param_insert(self, PI_BAUD_RATE, skb_tail_pointer(skb),
 				skb_tailroom(skb), &irlap_param_info);
 	if (ret < 0)
 		return ret;
 	skb_put(skb, ret);
 
 	/* Insert max turnaround time */
-	ret = irda_param_insert(self, PI_MAX_TURN_TIME, skb->tail,
+	ret = irda_param_insert(self, PI_MAX_TURN_TIME, skb_tail_pointer(skb),
 				skb_tailroom(skb), &irlap_param_info);
 	if (ret < 0)
 		return ret;
 	skb_put(skb, ret);
 
 	/* Insert data size */
-	ret = irda_param_insert(self, PI_DATA_SIZE, skb->tail,
+	ret = irda_param_insert(self, PI_DATA_SIZE, skb_tail_pointer(skb),
 				skb_tailroom(skb), &irlap_param_info);
 	if (ret < 0)
 		return ret;
 	skb_put(skb, ret);
 
 	/* Insert window size */
-	ret = irda_param_insert(self, PI_WINDOW_SIZE, skb->tail,
+	ret = irda_param_insert(self, PI_WINDOW_SIZE, skb_tail_pointer(skb),
 				skb_tailroom(skb), &irlap_param_info);
 	if (ret < 0)
 		return ret;
 	skb_put(skb, ret);
 
 	/* Insert additional BOFs */
-	ret = irda_param_insert(self, PI_ADD_BOFS, skb->tail,
+	ret = irda_param_insert(self, PI_ADD_BOFS, skb_tail_pointer(skb),
 				skb_tailroom(skb), &irlap_param_info);
 	if (ret < 0)
 		return ret;
 	skb_put(skb, ret);
 
 	/* Insert minimum turnaround time */
-	ret = irda_param_insert(self, PI_MIN_TURN_TIME, skb->tail,
+	ret = irda_param_insert(self, PI_MIN_TURN_TIME, skb_tail_pointer(skb),
 				skb_tailroom(skb), &irlap_param_info);
 	if (ret < 0)
 		return ret;
 	skb_put(skb, ret);
 
 	/* Insert link disconnect/threshold time */
-	ret = irda_param_insert(self, PI_LINK_DISC, skb->tail,
+	ret = irda_param_insert(self, PI_LINK_DISC, skb_tail_pointer(skb),
 				skb_tailroom(skb), &irlap_param_info);
 	if (ret < 0)
 		return ret;
diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
index 48f0531..442300c 100644
--- a/net/netfilter/nf_conntrack_netlink.c
+++ b/net/netfilter/nf_conntrack_netlink.c
@@ -268,9 +268,7 @@
 	struct nlmsghdr *nlh;
 	struct nfgenmsg *nfmsg;
 	struct nfattr *nest_parms;
-	unsigned char *b;
-
-	b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	event |= NFNL_SUBSYS_CTNETLINK << 8;
 	nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
@@ -303,7 +301,7 @@
 	    ctnetlink_dump_use(skb, ct) < 0)
 		goto nfattr_failure;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
@@ -322,7 +320,7 @@
 	struct nf_conn *ct = (struct nf_conn *)ptr;
 	struct sk_buff *skb;
 	unsigned int type;
-	unsigned char *b;
+	sk_buff_data_t b;
 	unsigned int flags = 0, group;
 
 	/* ignore our fake conntrack entry */
@@ -1152,9 +1150,7 @@
 {
 	struct nlmsghdr *nlh;
 	struct nfgenmsg *nfmsg;
-	unsigned char *b;
-
-	b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	event |= NFNL_SUBSYS_CTNETLINK_EXP << 8;
 	nlh    = NLMSG_PUT(skb, pid, seq, event, sizeof(struct nfgenmsg));
@@ -1168,7 +1164,7 @@
 	if (ctnetlink_exp_dump_expect(skb, exp) < 0)
 		goto nfattr_failure;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
@@ -1186,7 +1182,7 @@
 	struct nf_conntrack_expect *exp = (struct nf_conntrack_expect *)ptr;
 	struct sk_buff *skb;
 	unsigned int type;
-	unsigned char *b;
+	sk_buff_data_t b;
 	int flags = 0;
 
 	if (events & IPEXP_NEW) {
diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c
index 5eeebd2..9709f94 100644
--- a/net/netfilter/nfnetlink_log.c
+++ b/net/netfilter/nfnetlink_log.c
@@ -409,15 +409,14 @@
 			const struct nf_loginfo *li,
 			const char *prefix, unsigned int plen)
 {
-	unsigned char *old_tail;
 	struct nfulnl_msg_packet_hdr pmsg;
 	struct nlmsghdr *nlh;
 	struct nfgenmsg *nfmsg;
 	__be32 tmp_uint;
+	sk_buff_data_t old_tail = inst->skb->tail;
 
 	UDEBUG("entered\n");
 
-	old_tail = inst->skb->tail;
 	nlh = NLMSG_PUT(inst->skb, 0, 0,
 			NFNL_SUBSYS_ULOG << 8 | NFULNL_MSG_PACKET,
 			sizeof(struct nfgenmsg));
diff --git a/net/netfilter/nfnetlink_queue.c b/net/netfilter/nfnetlink_queue.c
index cfbee39..b6585ca 100644
--- a/net/netfilter/nfnetlink_queue.c
+++ b/net/netfilter/nfnetlink_queue.c
@@ -338,7 +338,7 @@
 nfqnl_build_packet_message(struct nfqnl_instance *queue,
 			   struct nfqnl_queue_entry *entry, int *errp)
 {
-	unsigned char *old_tail;
+	sk_buff_data_t old_tail;
 	size_t size;
 	size_t data_len = 0;
 	struct sk_buff *skb;
@@ -404,7 +404,7 @@
 	if (!skb)
 		goto nlmsg_failure;
 
-	old_tail= skb->tail;
+	old_tail = skb->tail;
 	nlh = NLMSG_PUT(skb, 0, 0,
 			NFNL_SUBSYS_QUEUE << 8 | NFQNL_MSG_PACKET,
 			sizeof(struct nfgenmsg));
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 50dc5ed..fdb6eb1 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -785,7 +785,7 @@
 
 	skb_orphan(skb);
 
-	delta = skb->end - skb->tail;
+	delta = skb->end - skb_tail_pointer(skb);
 	if (delta * 2 < skb->truesize)
 		return skb;
 
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 51c059b..36388b2 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -775,7 +775,7 @@
 		err = -EINVAL;
 		res = dev->hard_header(skb, dev, ntohs(proto), addr, NULL, len);
 		if (sock->type != SOCK_DGRAM) {
-			skb->tail = skb->data;
+			skb_reset_tail_pointer(skb);
 			skb->len = 0;
 		} else if (res < 0)
 			goto out_free;
diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index cb21617..28326fb 100644
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -93,7 +93,7 @@
 				continue;
 			a->priv = p;
 			a->order = n_i;
-			r = (struct rtattr*) skb->tail;
+			r = (struct rtattr *)skb_tail_pointer(skb);
 			RTA_PUT(skb, a->order, 0, NULL);
 			err = tcf_action_dump_1(skb, a, 0, 0);
 			if (err < 0) {
@@ -101,7 +101,7 @@
 				skb_trim(skb, (u8*)r - skb->data);
 				goto done;
 			}
-			r->rta_len = skb->tail - (u8*)r;
+			r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 			n_i++;
 			if (n_i >= TCA_ACT_MAX_PRIO)
 				goto done;
@@ -125,7 +125,7 @@
 	struct rtattr *r ;
 	int i= 0, n_i = 0;
 
-	r = (struct rtattr*) skb->tail;
+	r = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, a->order, 0, NULL);
 	RTA_PUT(skb, TCA_KIND, IFNAMSIZ, a->ops->kind);
 	for (i = 0; i < (hinfo->hmask + 1); i++) {
@@ -140,7 +140,7 @@
 		}
 	}
 	RTA_PUT(skb, TCA_FCNT, 4, &n_i);
-	r->rta_len = skb->tail - (u8*)r;
+	r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 
 	return n_i;
 rtattr_failure:
@@ -423,7 +423,7 @@
 tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
 	int err = -EINVAL;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *r;
 
 	if (a->ops == NULL || a->ops->dump == NULL)
@@ -432,10 +432,10 @@
 	RTA_PUT(skb, TCA_KIND, IFNAMSIZ, a->ops->kind);
 	if (tcf_action_copy_stats(skb, a, 0))
 		goto rtattr_failure;
-	r = (struct rtattr*) skb->tail;
+	r = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	if ((err = tcf_action_dump_old(skb, a, bind, ref)) > 0) {
-		r->rta_len = skb->tail - (u8*)r;
+		r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 		return err;
 	}
 
@@ -449,17 +449,17 @@
 {
 	struct tc_action *a;
 	int err = -EINVAL;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *r ;
 
 	while ((a = act) != NULL) {
-		r = (struct rtattr*) skb->tail;
+		r = (struct rtattr *)skb_tail_pointer(skb);
 		act = a->next;
 		RTA_PUT(skb, a->order, 0, NULL);
 		err = tcf_action_dump_1(skb, a, bind, ref);
 		if (err < 0)
 			goto errout;
-		r->rta_len = skb->tail - (u8*)r;
+		r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 	}
 
 	return 0;
@@ -635,7 +635,7 @@
 {
 	struct tcamsg *t;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *x;
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
@@ -645,15 +645,15 @@
 	t->tca__pad1 = 0;
 	t->tca__pad2 = 0;
 
-	x = (struct rtattr*) skb->tail;
+	x = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 
 	if (tcf_action_dump(skb, a, bind, ref) < 0)
 		goto rtattr_failure;
 
-	x->rta_len = skb->tail - (u8*)x;
+	x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
@@ -767,7 +767,7 @@
 		return -ENOBUFS;
 	}
 
-	b = (unsigned char *)skb->tail;
+	b = skb_tail_pointer(skb);
 
 	if (rtattr_parse_nested(tb, TCA_ACT_MAX, rta) < 0)
 		goto err_out;
@@ -783,16 +783,16 @@
 	t->tca__pad1 = 0;
 	t->tca__pad2 = 0;
 
-	x = (struct rtattr *) skb->tail;
+	x = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 
 	err = a->ops->walk(skb, &dcb, RTM_DELACTION, a);
 	if (err < 0)
 		goto rtattr_failure;
 
-	x->rta_len = skb->tail - (u8 *) x;
+	x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	nlh->nlmsg_flags |= NLM_F_ROOT;
 	module_put(a->ops->owner);
 	kfree(a);
@@ -884,7 +884,7 @@
 	if (!skb)
 		return -ENOBUFS;
 
-	b = (unsigned char *)skb->tail;
+	b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*t), flags);
 	t = NLMSG_DATA(nlh);
@@ -892,15 +892,15 @@
 	t->tca__pad1 = 0;
 	t->tca__pad2 = 0;
 
-	x = (struct rtattr*) skb->tail;
+	x = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 
 	if (tcf_action_dump(skb, a, 0, 0) < 0)
 		goto rtattr_failure;
 
-	x->rta_len = skb->tail - (u8*)x;
+	x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	NETLINK_CB(skb).dst_group = RTNLGRP_TC;
 
 	err = rtnetlink_send(skb, pid, RTNLGRP_TC, flags&NLM_F_ECHO);
@@ -1015,7 +1015,7 @@
 tc_dump_action(struct sk_buff *skb, struct netlink_callback *cb)
 {
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *x;
 	struct tc_action_ops *a_o;
 	struct tc_action a;
@@ -1048,7 +1048,7 @@
 	t->tca__pad1 = 0;
 	t->tca__pad2 = 0;
 
-	x = (struct rtattr *) skb->tail;
+	x = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_ACT_TAB, 0, NULL);
 
 	ret = a_o->walk(skb, cb, RTM_GETACTION, &a);
@@ -1056,12 +1056,12 @@
 		goto rtattr_failure;
 
 	if (ret > 0) {
-		x->rta_len = skb->tail - (u8 *) x;
+		x->rta_len = skb_tail_pointer(skb) - (u8 *)x;
 		ret = skb->len;
 	} else
 		skb_trim(skb, (u8*)x - skb->data);
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	if (NETLINK_CB(cb->skb).pid && ret)
 		nlh->nlmsg_flags |= NLM_F_MULTI;
 	module_put(a_o->owner);
diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
index 87d0faf..aad748b 100644
--- a/net/sched/act_gact.c
+++ b/net/sched/act_gact.c
@@ -155,7 +155,7 @@
 
 static int tcf_gact_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_gact opt;
 	struct tcf_gact *gact = a->priv;
 	struct tcf_t t;
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c
index 47f0b13..2ccfd5b 100644
--- a/net/sched/act_ipt.c
+++ b/net/sched/act_ipt.c
@@ -245,7 +245,7 @@
 
 static int tcf_ipt_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_ipt *ipt = a->priv;
 	struct ipt_entry_target *t;
 	struct tcf_t tm;
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 3e93683..15f6ecd 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -206,7 +206,7 @@
 
 static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_mirred *m = a->priv;
 	struct tc_mirred opt;
 	struct tcf_t t;
diff --git a/net/sched/act_pedit.c b/net/sched/act_pedit.c
index 20813ee..d654cea 100644
--- a/net/sched/act_pedit.c
+++ b/net/sched/act_pedit.c
@@ -195,7 +195,7 @@
 static int tcf_pedit_dump(struct sk_buff *skb, struct tc_action *a,
 			  int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_pedit *p = a->priv;
 	struct tc_pedit *opt;
 	struct tcf_t t;
diff --git a/net/sched/act_police.c b/net/sched/act_police.c
index 10a5a5c..068b237 100644
--- a/net/sched/act_police.c
+++ b/net/sched/act_police.c
@@ -80,7 +80,7 @@
 				continue;
 			a->priv = p;
 			a->order = index;
-			r = (struct rtattr*) skb->tail;
+			r = (struct rtattr *)skb_tail_pointer(skb);
 			RTA_PUT(skb, a->order, 0, NULL);
 			if (type == RTM_DELACTION)
 				err = tcf_action_dump_1(skb, a, 0, 1);
@@ -91,7 +91,7 @@
 				skb_trim(skb, (u8*)r - skb->data);
 				goto done;
 			}
-			r->rta_len = skb->tail - (u8*)r;
+			r->rta_len = skb_tail_pointer(skb) - (u8 *)r;
 			n_i++;
 		}
 	}
@@ -326,7 +326,7 @@
 static int
 tcf_act_police_dump(struct sk_buff *skb, struct tc_action *a, int bind, int ref)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_police *police = a->priv;
 	struct tc_police opt;
 
@@ -572,7 +572,7 @@
 
 int tcf_police_dump(struct sk_buff *skb, struct tcf_police *police)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_police opt;
 
 	opt.index = police->tcf_index;
diff --git a/net/sched/act_simple.c b/net/sched/act_simple.c
index c797118..ecbcfa5 100644
--- a/net/sched/act_simple.c
+++ b/net/sched/act_simple.c
@@ -155,7 +155,7 @@
 static inline int tcf_simp_dump(struct sk_buff *skb, struct tc_action *a,
 				int bind, int ref)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_defact *d = a->priv;
 	struct tc_defact opt;
 	struct tcf_t t;
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 5c6ffdb..84231ba 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -323,7 +323,7 @@
 {
 	struct tcmsg *tcm;
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
 	tcm = NLMSG_DATA(nlh);
@@ -340,7 +340,7 @@
 		if (tp->ops->dump && tp->ops->dump(tp, fh, skb, tcm) < 0)
 			goto rtattr_failure;
 	}
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
@@ -563,30 +563,30 @@
 		 * to work with both old and new modes of entering
 		 * tc data even if iproute2  was newer - jhs
 		 */
-		struct rtattr * p_rta = (struct rtattr*) skb->tail;
+		struct rtattr *p_rta = (struct rtattr *)skb_tail_pointer(skb);
 
 		if (exts->action->type != TCA_OLD_COMPAT) {
 			RTA_PUT(skb, map->action, 0, NULL);
 			if (tcf_action_dump(skb, exts->action, 0, 0) < 0)
 				goto rtattr_failure;
-			p_rta->rta_len = skb->tail - (u8*)p_rta;
+			p_rta->rta_len = skb_tail_pointer(skb) - (u8 *)p_rta;
 		} else if (map->police) {
 			RTA_PUT(skb, map->police, 0, NULL);
 			if (tcf_action_dump_old(skb, exts->action, 0, 0) < 0)
 				goto rtattr_failure;
-			p_rta->rta_len = skb->tail - (u8*)p_rta;
+			p_rta->rta_len = skb_tail_pointer(skb) - (u8 *)p_rta;
 		}
 	}
 #elif defined CONFIG_NET_CLS_POLICE
 	if (map->police && exts->police) {
-		struct rtattr * p_rta = (struct rtattr*) skb->tail;
+		struct rtattr *p_rta = (struct rtattr *)skb_tail_pointer(skb);
 
 		RTA_PUT(skb, map->police, 0, NULL);
 
 		if (tcf_police_dump(skb, exts->police) < 0)
 			goto rtattr_failure;
 
-		p_rta->rta_len = skb->tail - (u8*)p_rta;
+		p_rta->rta_len = skb_tail_pointer(skb) - (u8 *)p_rta;
 	}
 #endif
 	return 0;
diff --git a/net/sched/cls_basic.c b/net/sched/cls_basic.c
index 4a91f08..800ec2a 100644
--- a/net/sched/cls_basic.c
+++ b/net/sched/cls_basic.c
@@ -245,7 +245,7 @@
 		      struct sk_buff *skb, struct tcmsg *t)
 {
 	struct basic_filter *f = (struct basic_filter *) fh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	if (f == NULL)
@@ -263,7 +263,7 @@
 	    tcf_em_tree_dump(skb, &f->ematches, TCA_BASIC_EMATCHES) < 0)
 		goto rtattr_failure;
 
-	rta->rta_len = (skb->tail - b);
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
diff --git a/net/sched/cls_fw.c b/net/sched/cls_fw.c
index 5dbb9d4..f5f3558 100644
--- a/net/sched/cls_fw.c
+++ b/net/sched/cls_fw.c
@@ -348,7 +348,7 @@
 {
 	struct fw_head *head = (struct fw_head *)tp->root;
 	struct fw_filter *f = (struct fw_filter*)fh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	if (f == NULL)
@@ -374,7 +374,7 @@
 	if (tcf_exts_dump(skb, &f->exts, &fw_ext_map) < 0)
 		goto rtattr_failure;
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	if (tcf_exts_dump_stats(skb, &f->exts, &fw_ext_map) < 0)
 		goto rtattr_failure;
diff --git a/net/sched/cls_route.c b/net/sched/cls_route.c
index abc47cc..1f94df3 100644
--- a/net/sched/cls_route.c
+++ b/net/sched/cls_route.c
@@ -562,7 +562,7 @@
 		       struct sk_buff *skb, struct tcmsg *t)
 {
 	struct route4_filter *f = (struct route4_filter*)fh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	u32 id;
 
@@ -591,7 +591,7 @@
 	if (tcf_exts_dump(skb, &f->exts, &route_ext_map) < 0)
 		goto rtattr_failure;
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	if (tcf_exts_dump_stats(skb, &f->exts, &route_ext_map) < 0)
 		goto rtattr_failure;
diff --git a/net/sched/cls_rsvp.h b/net/sched/cls_rsvp.h
index 6f373b0..87ed6f3 100644
--- a/net/sched/cls_rsvp.h
+++ b/net/sched/cls_rsvp.h
@@ -593,7 +593,7 @@
 {
 	struct rsvp_filter *f = (struct rsvp_filter*)fh;
 	struct rsvp_session *s;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	struct tc_rsvp_pinfo pinfo;
 
@@ -623,7 +623,7 @@
 	if (tcf_exts_dump(skb, &f->exts, &rsvp_ext_map) < 0)
 		goto rtattr_failure;
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	if (tcf_exts_dump_stats(skb, &f->exts, &rsvp_ext_map) < 0)
 		goto rtattr_failure;
diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index 7563fdc..0537d60 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -448,7 +448,7 @@
 {
 	struct tcindex_data *p = PRIV(tp);
 	struct tcindex_filter_result *r = (struct tcindex_filter_result *) fh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	DPRINTK("tcindex_dump(tp %p,fh 0x%lx,skb %p,t %p),p %p,r %p,b %p\n",
@@ -463,7 +463,7 @@
 		RTA_PUT(skb,TCA_TCINDEX_SHIFT,sizeof(p->shift),&p->shift);
 		RTA_PUT(skb,TCA_TCINDEX_FALL_THROUGH,sizeof(p->fall_through),
 		    &p->fall_through);
-		rta->rta_len = skb->tail-b;
+		rta->rta_len = skb_tail_pointer(skb) - b;
 	} else {
 		if (p->perfect) {
 			t->tcm_handle = r-p->perfect;
@@ -486,7 +486,7 @@
 
 		if (tcf_exts_dump(skb, &r->exts, &tcindex_ext_map) < 0)
 			goto rtattr_failure;
-		rta->rta_len = skb->tail-b;
+		rta->rta_len = skb_tail_pointer(skb) - b;
 
 		if (tcf_exts_dump_stats(skb, &r->exts, &tcindex_ext_map) < 0)
 			goto rtattr_failure;
diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c
index 695b340..fa11bb7 100644
--- a/net/sched/cls_u32.c
+++ b/net/sched/cls_u32.c
@@ -213,7 +213,7 @@
 			off2 = 0;
 		}
 
-		if (ptr < skb->tail)
+		if (ptr < skb_tail_pointer(skb))
 			goto next_ht;
 	}
 
@@ -718,7 +718,7 @@
 		     struct sk_buff *skb, struct tcmsg *t)
 {
 	struct tc_u_knode *n = (struct tc_u_knode*)fh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	if (n == NULL)
@@ -765,7 +765,7 @@
 #endif
 	}
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	if (TC_U32_KEY(n->handle))
 		if (tcf_exts_dump_stats(skb, &n->exts, &u32_ext_map) < 0)
 			goto rtattr_failure;
diff --git a/net/sched/ematch.c b/net/sched/ematch.c
index 959c306..63146d3 100644
--- a/net/sched/ematch.c
+++ b/net/sched/ematch.c
@@ -418,17 +418,19 @@
 int tcf_em_tree_dump(struct sk_buff *skb, struct tcf_ematch_tree *tree, int tlv)
 {
 	int i;
-	struct rtattr * top_start = (struct rtattr*) skb->tail;
-	struct rtattr * list_start;
+	u8 *tail;
+	struct rtattr *top_start = (struct rtattr *)skb_tail_pointer(skb);
+	struct rtattr *list_start;
 
 	RTA_PUT(skb, tlv, 0, NULL);
 	RTA_PUT(skb, TCA_EMATCH_TREE_HDR, sizeof(tree->hdr), &tree->hdr);
 
-	list_start = (struct rtattr *) skb->tail;
+	list_start = (struct rtattr *)skb_tail_pointer(skb);
 	RTA_PUT(skb, TCA_EMATCH_TREE_LIST, 0, NULL);
 
+	tail = skb_tail_pointer(skb);
 	for (i = 0; i < tree->hdr.nmatches; i++) {
-		struct rtattr *match_start = (struct rtattr*) skb->tail;
+		struct rtattr *match_start = (struct rtattr *)tail;
 		struct tcf_ematch *em = tcf_em_get_match(tree, i);
 		struct tcf_ematch_hdr em_hdr = {
 			.kind = em->ops ? em->ops->kind : TCF_EM_CONTAINER,
@@ -447,11 +449,12 @@
 		} else if (em->datalen > 0)
 			RTA_PUT_NOHDR(skb, em->datalen, (void *) em->data);
 
-		match_start->rta_len = skb->tail - (u8*) match_start;
+		tail = skb_tail_pointer(skb);
+		match_start->rta_len = tail - (u8 *)match_start;
 	}
 
-	list_start->rta_len = skb->tail - (u8 *) list_start;
-	top_start->rta_len = skb->tail - (u8 *) top_start;
+	list_start->rta_len = tail - (u8 *)list_start;
+	top_start->rta_len = tail - (u8 *)top_start;
 
 	return 0;
 
diff --git a/net/sched/sch_api.c b/net/sched/sch_api.c
index ecbdc6b..7482a95 100644
--- a/net/sched/sch_api.c
+++ b/net/sched/sch_api.c
@@ -813,7 +813,7 @@
 {
 	struct tcmsg *tcm;
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct gnet_dump d;
 
 	nlh = NLMSG_NEW(skb, pid, seq, event, sizeof(*tcm), flags);
@@ -847,7 +847,7 @@
 	if (gnet_stats_finish_copy(&d) < 0)
 		goto rtattr_failure;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
@@ -1051,7 +1051,7 @@
 {
 	struct tcmsg *tcm;
 	struct nlmsghdr  *nlh;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct gnet_dump d;
 	struct Qdisc_class_ops *cl_ops = q->ops->cl_ops;
 
@@ -1076,7 +1076,7 @@
 	if (gnet_stats_finish_copy(&d) < 0)
 		goto rtattr_failure;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
diff --git a/net/sched/sch_atm.c b/net/sched/sch_atm.c
index baca874..1d7bb16 100644
--- a/net/sched/sch_atm.c
+++ b/net/sched/sch_atm.c
@@ -631,7 +631,7 @@
 {
 	struct atm_qdisc_data *p = PRIV(sch);
 	struct atm_flow_data *flow = (struct atm_flow_data *) cl;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	DPRINTK("atm_tc_dump_class(sch %p,[qdisc %p],flow %p,skb %p,tcm %p)\n",
@@ -661,7 +661,7 @@
 
 		RTA_PUT(skb,TCA_ATM_EXCESS,sizeof(zero),&zero);
 	}
-	rta->rta_len = skb->tail-b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c
index d83414d..be98a01 100644
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -1465,7 +1465,7 @@
 
 static __inline__ int cbq_dump_rate(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	RTA_PUT(skb, TCA_CBQ_RATE, sizeof(cl->R_tab->rate), &cl->R_tab->rate);
 	return skb->len;
@@ -1477,7 +1477,7 @@
 
 static __inline__ int cbq_dump_lss(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_lssopt opt;
 
 	opt.flags = 0;
@@ -1502,7 +1502,7 @@
 
 static __inline__ int cbq_dump_wrr(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_wrropt opt;
 
 	opt.flags = 0;
@@ -1520,7 +1520,7 @@
 
 static __inline__ int cbq_dump_ovl(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_ovl opt;
 
 	opt.strategy = cl->ovl_strategy;
@@ -1537,7 +1537,7 @@
 
 static __inline__ int cbq_dump_fopt(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_fopt opt;
 
 	if (cl->split || cl->defmap) {
@@ -1556,7 +1556,7 @@
 #ifdef CONFIG_NET_CLS_POLICE
 static __inline__ int cbq_dump_police(struct sk_buff *skb, struct cbq_class *cl)
 {
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_cbq_police opt;
 
 	if (cl->police) {
@@ -1590,14 +1590,14 @@
 static int cbq_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct cbq_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	rta = (struct rtattr*)b;
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	if (cbq_dump_attr(skb, &q->link) < 0)
 		goto rtattr_failure;
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
@@ -1619,7 +1619,7 @@
 	       struct sk_buff *skb, struct tcmsg *tcm)
 {
 	struct cbq_class *cl = (struct cbq_class*)arg;
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	if (cl->tparent)
@@ -1633,7 +1633,7 @@
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	if (cbq_dump_attr(skb, cl) < 0)
 		goto rtattr_failure;
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c
index 5197b6c..80e6f81 100644
--- a/net/sched/sch_hfsc.c
+++ b/net/sched/sch_hfsc.c
@@ -1363,7 +1363,7 @@
 		struct tcmsg *tcm)
 {
 	struct hfsc_class *cl = (struct hfsc_class *)arg;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta = (struct rtattr *)b;
 
 	tcm->tcm_parent = cl->cl_parent ? cl->cl_parent->classid : TC_H_ROOT;
@@ -1374,7 +1374,7 @@
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	if (hfsc_dump_curves(skb, cl) < 0)
 		goto rtattr_failure;
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
  rtattr_failure:
@@ -1576,7 +1576,7 @@
 hfsc_dump_qdisc(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct hfsc_sched *q = qdisc_priv(sch);
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_hfsc_qopt qopt;
 
 	qopt.defcls = q->defcls;
diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index f76c20c..c687388 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -1110,7 +1110,7 @@
 static int htb_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct htb_sched *q = qdisc_priv(sch);
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	struct tc_htb_glob gopt;
 	spin_lock_bh(&sch->dev->queue_lock);
@@ -1123,12 +1123,12 @@
 	rta = (struct rtattr *)b;
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
 	RTA_PUT(skb, TCA_HTB_INIT, sizeof(gopt), &gopt);
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	spin_unlock_bh(&sch->dev->queue_lock);
 	return skb->len;
 rtattr_failure:
 	spin_unlock_bh(&sch->dev->queue_lock);
-	skb_trim(skb, skb->tail - skb->data);
+	skb_trim(skb, skb_tail_pointer(skb) - skb->data);
 	return -1;
 }
 
@@ -1136,7 +1136,7 @@
 			  struct sk_buff *skb, struct tcmsg *tcm)
 {
 	struct htb_class *cl = (struct htb_class *)arg;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	struct tc_htb_opt opt;
 
@@ -1159,7 +1159,7 @@
 	opt.prio = cl->un.leaf.prio;
 	opt.level = cl->level;
 	RTA_PUT(skb, TCA_HTB_PARMS, sizeof(opt), &opt);
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	spin_unlock_bh(&sch->dev->queue_lock);
 	return skb->len;
 rtattr_failure:
diff --git a/net/sched/sch_ingress.c b/net/sched/sch_ingress.c
index cfe070e..d19f407 100644
--- a/net/sched/sch_ingress.c
+++ b/net/sched/sch_ingress.c
@@ -362,12 +362,12 @@
 
 static int ingress_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 
 	rta = (struct rtattr *) b;
 	RTA_PUT(skb, TCA_OPTIONS, 0, NULL);
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
diff --git a/net/sched/sch_netem.c b/net/sched/sch_netem.c
index 915f82a..2a9b1e4 100644
--- a/net/sched/sch_netem.c
+++ b/net/sched/sch_netem.c
@@ -583,7 +583,7 @@
 static int netem_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	const struct netem_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta = (struct rtattr *) b;
 	struct tc_netem_qopt qopt;
 	struct tc_netem_corr cor;
@@ -611,7 +611,7 @@
 	corrupt.correlation = q->corrupt_cor.rho;
 	RTA_PUT(skb, TCA_NETEM_CORRUPT, sizeof(corrupt), &corrupt);
 
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	return skb->len;
 
diff --git a/net/sched/sch_prio.c b/net/sched/sch_prio.c
index de889f2..5b37110 100644
--- a/net/sched/sch_prio.c
+++ b/net/sched/sch_prio.c
@@ -271,7 +271,7 @@
 static int prio_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct prio_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_prio_qopt opt;
 
 	opt.bands = q->bands;
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c
index e369540..a511ba8 100644
--- a/net/sched/sch_sfq.c
+++ b/net/sched/sch_sfq.c
@@ -461,7 +461,7 @@
 static int sfq_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct sfq_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct tc_sfq_qopt opt;
 
 	opt.quantum = q->quantum;
diff --git a/net/sched/sch_tbf.c b/net/sched/sch_tbf.c
index f14692f..2318955 100644
--- a/net/sched/sch_tbf.c
+++ b/net/sched/sch_tbf.c
@@ -387,7 +387,7 @@
 static int tbf_dump(struct Qdisc *sch, struct sk_buff *skb)
 {
 	struct tbf_sched_data *q = qdisc_priv(sch);
-	unsigned char	 *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	struct rtattr *rta;
 	struct tc_tbf_qopt opt;
 
@@ -403,7 +403,7 @@
 	opt.mtu = q->mtu;
 	opt.buffer = q->buffer;
 	RTA_PUT(skb, TCA_TBF_PARMS, sizeof(opt), &opt);
-	rta->rta_len = skb->tail - b;
+	rta->rta_len = skb_tail_pointer(skb) - b;
 
 	return skb->len;
 
diff --git a/net/sctp/input.c b/net/sctp/input.c
index 1ff47b1..18b97ee 100644
--- a/net/sctp/input.c
+++ b/net/sctp/input.c
@@ -612,7 +612,7 @@
 			break;
 
 		ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length));
-		if (ch_end > skb->tail)
+		if (ch_end > skb_tail_pointer(skb))
 			break;
 
 		/* RFC 8.4, 2) If the OOTB packet contains an ABORT chunk, the
@@ -644,7 +644,7 @@
 		}
 
 		ch = (sctp_chunkhdr_t *) ch_end;
-	} while (ch_end < skb->tail);
+	} while (ch_end < skb_tail_pointer(skb));
 
 	return 0;
 
diff --git a/net/sctp/inqueue.c b/net/sctp/inqueue.c
index c30629e..88aa224 100644
--- a/net/sctp/inqueue.c
+++ b/net/sctp/inqueue.c
@@ -159,16 +159,16 @@
 	 * the skb->tail.
 	 */
 	if (unlikely(skb_is_nonlinear(chunk->skb))) {
-		if (chunk->chunk_end > chunk->skb->tail)
-			chunk->chunk_end = chunk->skb->tail;
+		if (chunk->chunk_end > skb_tail_pointer(chunk->skb))
+			chunk->chunk_end = skb_tail_pointer(chunk->skb);
 	}
 	skb_pull(chunk->skb, sizeof(sctp_chunkhdr_t));
 	chunk->subh.v = NULL; /* Subheader is no longer valid.  */
 
-	if (chunk->chunk_end < chunk->skb->tail) {
+	if (chunk->chunk_end < skb_tail_pointer(chunk->skb)) {
 		/* This is not a singleton */
 		chunk->singleton = 0;
-	} else if (chunk->chunk_end > chunk->skb->tail) {
+	} else if (chunk->chunk_end > skb_tail_pointer(chunk->skb)) {
 		/* RFC 2960, Section 6.10  Bundling
 		 *
 		 * Partial chunks MUST NOT be placed in an SCTP packet.
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 60c5b59..759ea3d 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -1143,7 +1143,7 @@
 
 	/* Adjust the chunk length field.  */
 	chunk->chunk_hdr->length = htons(chunklen + padlen + len);
-	chunk->chunk_end = chunk->skb->tail;
+	chunk->chunk_end = skb_tail_pointer(chunk->skb);
 
 	return target;
 }
@@ -1168,7 +1168,7 @@
 	/* Adjust the chunk length field.  */
 	chunk->chunk_hdr->length =
 		htons(ntohs(chunk->chunk_hdr->length) + len);
-	chunk->chunk_end = chunk->skb->tail;
+	chunk->chunk_end = skb_tail_pointer(chunk->skb);
 
 out:
 	return err;
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index bf502c4..438e5dc 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -3115,7 +3115,7 @@
 			break;
 
 		ch_end = ((__u8 *)ch) + WORD_ROUND(ntohs(ch->length));
-		if (ch_end > skb->tail)
+		if (ch_end > skb_tail_pointer(skb))
 			break;
 
 		if (SCTP_CID_SHUTDOWN_ACK == ch->type)
@@ -3130,7 +3130,7 @@
 			return sctp_sf_pdiscard(ep, asoc, type, arg, commands);
 
 		ch = (sctp_chunkhdr_t *) ch_end;
-	} while (ch_end < skb->tail);
+	} while (ch_end < skb_tail_pointer(skb));
 
 	if (ootb_shut_ack)
 		sctp_sf_shut_8_4_5(ep, asoc, type, arg, commands);
diff --git a/net/tipc/config.c b/net/tipc/config.c
index 14789a8..c71337a 100644
--- a/net/tipc/config.c
+++ b/net/tipc/config.c
@@ -89,7 +89,7 @@
 int tipc_cfg_append_tlv(struct sk_buff *buf, int tlv_type,
 			void *tlv_data, int tlv_data_size)
 {
-	struct tlv_desc *tlv = (struct tlv_desc *)buf->tail;
+	struct tlv_desc *tlv = (struct tlv_desc *)skb_tail_pointer(buf);
 	int new_tlv_space = TLV_SPACE(tlv_data_size);
 
 	if (skb_tailroom(buf) < new_tlv_space) {
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index b71739f..45832fb 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -1020,7 +1020,7 @@
 
 	if (!err) {
 		buf_crs = (unsigned char *)(TIPC_SKB_CB(buf)->handle);
-		sz = buf->tail - buf_crs;
+		sz = skb_tail_pointer(buf) - buf_crs;
 
 		needed = (buf_len - sz_copied);
 		sz_to_copy = (sz <= needed) ? sz : needed;
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c
index 816e369..814bb31 100644
--- a/net/xfrm/xfrm_user.c
+++ b/net/xfrm/xfrm_user.c
@@ -576,7 +576,7 @@
 	struct sk_buff *skb = sp->out_skb;
 	struct xfrm_usersa_info *p;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	if (sp->this_idx < sp->start_idx)
 		goto out;
@@ -621,7 +621,7 @@
 	if (x->lastused)
 		RTA_PUT(skb, XFRMA_LASTUSED, sizeof(x->lastused), &x->lastused);
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 out:
 	sp->this_idx++;
 	return 0;
@@ -1157,7 +1157,7 @@
 	struct sk_buff *in_skb = sp->in_skb;
 	struct sk_buff *skb = sp->out_skb;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	if (sp->this_idx < sp->start_idx)
 		goto out;
@@ -1176,7 +1176,7 @@
 	if (copy_to_user_policy_type(xp->type, skb) < 0)
 		goto nlmsg_failure;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 out:
 	sp->this_idx++;
 	return 0;
@@ -1330,7 +1330,7 @@
 	struct xfrm_aevent_id *id;
 	struct nlmsghdr *nlh;
 	struct xfrm_lifetime_cur ltime;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_PUT(skb, c->pid, c->seq, XFRM_MSG_NEWAE, sizeof(*id));
 	id = NLMSG_DATA(nlh);
@@ -1362,7 +1362,7 @@
 		RTA_PUT(skb,XFRMA_ETIMER_THRESH,sizeof(u32),&etimer);
 	}
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 rtattr_failure:
@@ -1744,7 +1744,7 @@
 	struct xfrm_migrate *mp;
 	struct xfrm_userpolicy_id *pol_id;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	int i;
 
 	nlh = NLMSG_PUT(skb, 0, 0, XFRM_MSG_MIGRATE, sizeof(*pol_id));
@@ -1764,7 +1764,7 @@
 			goto nlmsg_failure;
 	}
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 nlmsg_failure:
 	skb_trim(skb, b - skb->data);
@@ -1942,7 +1942,7 @@
 {
 	struct xfrm_user_expire *ue;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_PUT(skb, c->pid, 0, XFRM_MSG_EXPIRE,
 			sizeof(*ue));
@@ -1952,7 +1952,7 @@
 	copy_to_user_state(x, &ue->state);
 	ue->hard = (c->data.hard != 0) ? 1 : 0;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
@@ -1999,7 +1999,7 @@
 	struct xfrm_usersa_flush *p;
 	struct nlmsghdr *nlh;
 	struct sk_buff *skb;
-	unsigned char *b;
+	sk_buff_data_t b;
 	int len = NLMSG_LENGTH(sizeof(struct xfrm_usersa_flush));
 
 	skb = alloc_skb(len, GFP_ATOMIC);
@@ -2045,7 +2045,7 @@
 	struct xfrm_usersa_id *id;
 	struct nlmsghdr *nlh;
 	struct sk_buff *skb;
-	unsigned char *b;
+	sk_buff_data_t b;
 	int len = xfrm_sa_len(x);
 	int headlen;
 
@@ -2129,7 +2129,7 @@
 {
 	struct xfrm_user_acquire *ua;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 	__u32 seq = xfrm_get_acqseq();
 
 	nlh = NLMSG_PUT(skb, 0, 0, XFRM_MSG_ACQUIRE,
@@ -2153,7 +2153,7 @@
 	if (copy_to_user_policy_type(xp->type, skb) < 0)
 		goto nlmsg_failure;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
@@ -2249,7 +2249,7 @@
 	struct xfrm_user_polexpire *upe;
 	struct nlmsghdr *nlh;
 	int hard = c->data.hard;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_PUT(skb, c->pid, 0, XFRM_MSG_POLEXPIRE, sizeof(*upe));
 	upe = NLMSG_DATA(nlh);
@@ -2264,7 +2264,7 @@
 		goto nlmsg_failure;
 	upe->hard = !!hard;
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure:
@@ -2300,7 +2300,7 @@
 	struct xfrm_userpolicy_id *id;
 	struct nlmsghdr *nlh;
 	struct sk_buff *skb;
-	unsigned char *b;
+	sk_buff_data_t b;
 	int len = RTA_SPACE(sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr);
 	int headlen;
 
@@ -2357,7 +2357,7 @@
 {
 	struct nlmsghdr *nlh;
 	struct sk_buff *skb;
-	unsigned char *b;
+	sk_buff_data_t b;
 	int len = 0;
 #ifdef CONFIG_XFRM_SUB_POLICY
 	len += RTA_SPACE(sizeof(struct xfrm_userpolicy_type));
@@ -2410,7 +2410,7 @@
 {
 	struct xfrm_user_report *ur;
 	struct nlmsghdr *nlh;
-	unsigned char *b = skb->tail;
+	unsigned char *b = skb_tail_pointer(skb);
 
 	nlh = NLMSG_PUT(skb, 0, 0, XFRM_MSG_REPORT, sizeof(*ur));
 	ur = NLMSG_DATA(nlh);
@@ -2422,7 +2422,7 @@
 	if (addr)
 		RTA_PUT(skb, XFRMA_COADDR, sizeof(*addr), addr);
 
-	nlh->nlmsg_len = skb->tail - b;
+	nlh->nlmsg_len = skb_tail_pointer(skb) - b;
 	return skb->len;
 
 nlmsg_failure: