Merge nuts.davemloft.net:/disk1/BK/network-2.6

into nuts.davemloft.net:/disk1/BK/net-2.6

include/linux/netdevice.h

@@ -943,7 +943,7 @@ extern int		weight_p;
 extern unsigned long	netdev_fc_xoff;
 extern atomic_t netdev_dropping;
 extern int		netdev_set_master(struct net_device *dev, struct net_device *master);
-extern struct sk_buff * skb_checksum_help(struct sk_buff *skb);
+extern int skb_checksum_help(struct sk_buff **pskb, int inward);
 #ifdef CONFIG_NET_FASTROUTE
 extern int		netdev_fastroute;
 extern int		netdev_fastroute_obstacles;

include/net/dst.h

@@ -67,7 +67,7 @@ struct dst_entry
 	struct xfrm_state	*xfrm;
 
 	int			(*input)(struct sk_buff*);
-	int			(*output)(struct sk_buff*);
+	int			(*output)(struct sk_buff**);
 
 #ifdef CONFIG_NET_CLS_ROUTE
 	__u32			tclassid;
@@ -219,7 +219,7 @@ static inline int dst_output(struct sk_buff *skb)
 	int err;
 
 	for (;;) {
-		err = skb->dst->output(skb);
+		err = skb->dst->output(&skb);
 
 		if (likely(err == 0))
 			return err;

include/net/ip.h

@@ -92,8 +92,8 @@ extern int		ip_rcv(struct sk_buff *skb, struct net_device *dev,
 			       struct packet_type *pt);
 extern int		ip_local_deliver(struct sk_buff *skb);
 extern int		ip_mr_input(struct sk_buff *skb);
-extern int		ip_output(struct sk_buff *skb);
-extern int		ip_mc_output(struct sk_buff *skb);
+extern int		ip_output(struct sk_buff **pskb);
+extern int		ip_mc_output(struct sk_buff **pskb);
 extern int		ip_fragment(struct sk_buff *skb, int (*out)(struct sk_buff*));
 extern int		ip_do_nat(struct sk_buff *skb);
 extern void		ip_send_check(struct iphdr *ip);

include/net/ip6_route.h

@@ -65,7 +65,7 @@ extern struct rt6_info		*rt6_lookup(struct in6_addr *daddr,
 extern struct dst_entry *ndisc_dst_alloc(struct net_device *dev,
 					 struct neighbour *neigh,
 					 struct in6_addr *addr,
-					 int (*output)(struct sk_buff *));
+					 int (*output)(struct sk_buff **));
 extern int ndisc_dst_gc(int *more);
 extern void fib6_force_start_gc(void);
 

include/net/ipv6.h

@@ -355,8 +355,8 @@ extern int			ip6_dst_lookup(struct sock *sk,
  *	skb processing functions
  */
 
-extern int			ip6_output(struct sk_buff *skb);
-extern int			ip6_output2(struct sk_buff *skb);
+extern int			ip6_output(struct sk_buff **pskb);
+extern int			ip6_output2(struct sk_buff **pskb);
 extern int			ip6_forward(struct sk_buff *skb);
 extern int			ip6_input(struct sk_buff *skb);
 extern int			ip6_mc_input(struct sk_buff *skb);

include/net/xfrm.h

@@ -216,7 +216,7 @@ struct xfrm_type
 	void			(*destructor)(struct xfrm_state *);
 	int			(*input)(struct xfrm_state *, struct xfrm_decap_state *, struct sk_buff *skb);
 	int			(*post_input)(struct xfrm_state *, struct xfrm_decap_state *, struct sk_buff *skb);
-	int			(*output)(struct sk_buff *skb);
+	int			(*output)(struct sk_buff **pskb);
 	/* Estimate maximal size of result of transformation of a dgram */
 	u32			(*get_max_size)(struct xfrm_state *, int size);
 };

net/bridge/br_netfilter.c

@@ -165,7 +165,7 @@ static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb)
 		skb_pull(skb, VLAN_HLEN);
 		skb->nh.raw += VLAN_HLEN;
 	}
-	skb->dst->output(skb);
+	skb->dst->output(&skb);
 	return 0;
 }
 

net/core/dev.c

@@ -1180,28 +1180,46 @@ void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
 	rcu_read_unlock();
 }
 
-/* Calculate csum in the case, when packet is misrouted.
- * If it failed by some reason, ignore and send skb with wrong
- * checksum.
+/*
+ * Invalidate hardware checksum when packet is to be mangled, and
+ * complete checksum manually on outgoing path.
  */
-struct sk_buff *skb_checksum_help(struct sk_buff *skb)
+int skb_checksum_help(struct sk_buff **pskb, int inward)
 {
 	unsigned int csum;
-	int offset = skb->h.raw - skb->data;
+	int ret = 0, offset = (*pskb)->h.raw - (*pskb)->data;
+
+	if (inward) {
+		(*pskb)->ip_summed = CHECKSUM_NONE;
+		goto out;
+	}
 
-	if (offset > (int)skb->len)
+	if (skb_shared(*pskb)  || skb_cloned(*pskb)) {
+		struct sk_buff *newskb = skb_copy(*pskb, GFP_ATOMIC);
+		if (!newskb) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		if ((*pskb)->sk)
+			skb_set_owner_w(newskb, (*pskb)->sk);
+		kfree_skb(*pskb);
+		*pskb = newskb;
+	}
+
+	if (offset > (int)(*pskb)->len)
 		BUG();
-	csum = skb_checksum(skb, offset, skb->len-offset, 0);
+	csum = skb_checksum(*pskb, offset, (*pskb)->len-offset, 0);
 
-	offset = skb->tail - skb->h.raw;
+	offset = (*pskb)->tail - (*pskb)->h.raw;
 	if (offset <= 0)
 		BUG();
-	if (skb->csum + 2 > offset)
+	if ((*pskb)->csum + 2 > offset)
 		BUG();
 
-	*(u16*)(skb->h.raw + skb->csum) = csum_fold(csum);
-	skb->ip_summed = CHECKSUM_NONE;
-	return skb;
+	*(u16*)((*pskb)->h.raw + (*pskb)->csum) = csum_fold(csum);
+	(*pskb)->ip_summed = CHECKSUM_NONE;
+out:	
+	return ret;
 }
 
 #ifdef CONFIG_HIGHMEM
@@ -1326,10 +1344,9 @@ int dev_queue_xmit(struct sk_buff *skb)
 	if (skb->ip_summed == CHECKSUM_HW &&
 	    (!(dev->features & (NETIF_F_HW_CSUM | NETIF_F_NO_CSUM)) &&
 	     (!(dev->features & NETIF_F_IP_CSUM) ||
-	      skb->protocol != htons(ETH_P_IP)))) {
-		if ((skb = skb_checksum_help(skb)) == NULL)
-			goto out;
-	}
+	      skb->protocol != htons(ETH_P_IP))))
+	      	if (skb_checksum_help(&skb, 0))
+	      		goto out_kfree_skb;
 
 	/* Grab device queue */
 	spin_lock_bh(&dev->queue_lock);

net/core/dst.c

@@ -100,15 +100,15 @@ static void dst_run_gc(unsigned long dummy)
 	spin_unlock(&dst_lock);
 }
 
-static int dst_discard(struct sk_buff *skb)
+static int dst_discard_in(struct sk_buff *skb)
 {
 	kfree_skb(skb);
 	return 0;
 }
 
-static int dst_blackhole(struct sk_buff *skb)
+static int dst_discard_out(struct sk_buff **pskb)
 {
-	kfree_skb(skb);
+	kfree_skb(*pskb);
 	return 0;
 }
 
@@ -128,8 +128,8 @@ void * dst_alloc(struct dst_ops * ops)
 	dst->ops = ops;
 	dst->lastuse = jiffies;
 	dst->path = dst;
-	dst->input = dst_discard;
-	dst->output = dst_blackhole;
+	dst->input = dst_discard_in;
+	dst->output = dst_discard_out;
 #if RT_CACHE_DEBUG >= 2 
 	atomic_inc(&dst_total);
 #endif
@@ -143,8 +143,8 @@ static void ___dst_free(struct dst_entry * dst)
 	   protocol module is unloaded.
 	 */
 	if (dst->dev == NULL || !(dst->dev->flags&IFF_UP)) {
-		dst->input = dst_discard;
-		dst->output = dst_blackhole;
+		dst->input = dst_discard_in;
+		dst->output = dst_discard_out;
 	}
 	dst->obsolete = 2;
 }
@@ -228,19 +228,19 @@ static int dst_dev_event(struct notifier_block *this, unsigned long event, void
 				   _race_ _condition_.
 				 */
 				if (event!=NETDEV_DOWN &&
-				    dst->output == dst_blackhole) {
+				    dst->output == dst_discard_out) {
 					dst->dev = &loopback_dev;
 					dev_put(dev);
 					dev_hold(&loopback_dev);
-					dst->output = dst_discard;
+					dst->output = dst_discard_out;
 					if (dst->neighbour && dst->neighbour->dev == dev) {
 						dst->neighbour->dev = &loopback_dev;
 						dev_put(dev);
 						dev_hold(&loopback_dev);
 					}
 				} else {
-					dst->input = dst_discard;
-					dst->output = dst_blackhole;
+					dst->input = dst_discard_in;
+					dst->output = dst_discard_out;
 				}
 			}
 		}

net/core/netfilter.c

@@ -504,14 +504,6 @@ int nf_hook_slow(int pf, unsigned int hook, struct sk_buff *skb,
 	unsigned int verdict;
 	int ret = 0;
 
-	if (skb->ip_summed == CHECKSUM_HW) {
-		if (outdev == NULL) {
-			skb->ip_summed = CHECKSUM_NONE;
-		} else {
-			skb_checksum_help(skb);
-		}
-	}
-
 	/* We may already have this, but read-locks nest anyway */
 	rcu_read_lock();
 

net/decnet/dn_route.c

@@ -684,8 +684,9 @@ int dn_route_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type
 	return NET_RX_DROP;
 }
 
-static int dn_output(struct sk_buff *skb)
+static int dn_output(struct sk_buff **pskb)
 {
+	struct sk_buff *skb = *pskb;
 	struct dst_entry *dst = skb->dst;
 	struct dn_route *rt = (struct dn_route *)dst;
 	struct net_device *dev = dst->dev;
@@ -796,6 +797,11 @@ static int dn_rt_bug(struct sk_buff *skb)
 	return NET_RX_BAD;
 }
 
+static int dn_rt_bug_out(struct sk_buff **pskb)
+{
+	return dn_rt_bug(*pskb);
+}
+
 static int dn_rt_set_next_hop(struct dn_route *rt, struct dn_fib_res *res)
 {
 	struct dn_fib_info *fi = res->fi;
@@ -1387,7 +1393,7 @@ static int dn_route_input_slow(struct sk_buff *skb)
 	rt->u.dst.neighbour = neigh;
 	rt->u.dst.dev = out_dev;
 	rt->u.dst.lastuse = jiffies;
-	rt->u.dst.output = dn_rt_bug;
+	rt->u.dst.output = dn_rt_bug_out;
 	switch(res.type) {
 		case RTN_UNICAST:
 			rt->u.dst.input = dn_forward;

net/ipv4/ah4.c

@@ -54,10 +54,10 @@ static int ip_clear_mutable_options(struct iphdr *iph, u32 *daddr)
 	return 0;
 }
 
-static int ah_output(struct sk_buff *skb)
+static int ah_output(struct sk_buff **pskb)
 {
 	int err;
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = (*pskb)->dst;
 	struct xfrm_state *x  = dst->xfrm;
 	struct iphdr *iph, *top_iph;
 	struct ip_auth_hdr *ah;
@@ -67,23 +67,24 @@ static int ah_output(struct sk_buff *skb)
 		char 		buf[60];
 	} tmp_iph;
 
-	if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) {
-		err = -EINVAL;
-		goto error_nolock;
+	if ((*pskb)->ip_summed == CHECKSUM_HW) {
+		err = skb_checksum_help(pskb, 0);
+		if (err)
+			goto error_nolock;
 	}
 
 	spin_lock_bh(&x->lock);
-	err = xfrm_check_output(x, skb, AF_INET);
+	err = xfrm_check_output(x, *pskb, AF_INET);
 	if (err)
 		goto error;
 
-	iph = skb->nh.iph;
+	iph = (*pskb)->nh.iph;
 	if (x->props.mode) {
-		top_iph = (struct iphdr*)skb_push(skb, x->props.header_len);
+		top_iph = (struct iphdr*)skb_push(*pskb, x->props.header_len);
 		top_iph->ihl = 5;
 		top_iph->version = 4;
 		top_iph->tos = 0;
-		top_iph->tot_len = htons(skb->len);
+		top_iph->tot_len = htons((*pskb)->len);
 		top_iph->frag_off = 0;
 		if (!(iph->frag_off&htons(IP_DF)))
 			__ip_select_ident(top_iph, dst, 0);
@@ -95,12 +96,12 @@ static int ah_output(struct sk_buff *skb)
 		ah = (struct ip_auth_hdr*)(top_iph+1);
 		ah->nexthdr = IPPROTO_IPIP;
 	} else {
-		memcpy(&tmp_iph, skb->data, iph->ihl*4);
-		top_iph = (struct iphdr*)skb_push(skb, x->props.header_len);
+		memcpy(&tmp_iph, (*pskb)->data, iph->ihl*4);
+		top_iph = (struct iphdr*)skb_push(*pskb, x->props.header_len);
 		memcpy(top_iph, &tmp_iph, iph->ihl*4);
 		iph = &tmp_iph.iph;
 		top_iph->tos = 0;
-		top_iph->tot_len = htons(skb->len);
+		top_iph->tot_len = htons((*pskb)->len);
 		top_iph->frag_off = 0;
 		top_iph->ttl = 0;
 		top_iph->protocol = IPPROTO_AH;
@@ -120,14 +121,14 @@ static int ah_output(struct sk_buff *skb)
 	ah->reserved = 0;
 	ah->spi = x->id.spi;
 	ah->seq_no = htonl(++x->replay.oseq);
-	ahp->icv(ahp, skb, ah->auth_data);
+	ahp->icv(ahp, *pskb, ah->auth_data);
 	top_iph->tos = iph->tos;
 	top_iph->ttl = iph->ttl;
 	if (x->props.mode) {
 		if (x->props.flags & XFRM_STATE_NOECN)
 			IP_ECN_clear(top_iph);
 		top_iph->frag_off = iph->frag_off&~htons(IP_MF|IP_OFFSET);
-		memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
+		memset(&(IPCB(*pskb)->opt), 0, sizeof(struct ip_options));
 	} else {
 		top_iph->frag_off = iph->frag_off;
 		top_iph->daddr = iph->daddr;
@@ -136,12 +137,12 @@ static int ah_output(struct sk_buff *skb)
 	}
 	ip_send_check(top_iph);
 
-	skb->nh.raw = skb->data;
+	(*pskb)->nh.raw = (*pskb)->data;
 
-	x->curlft.bytes += skb->len;
+	x->curlft.bytes += (*pskb)->len;
 	x->curlft.packets++;
 	spin_unlock_bh(&x->lock);
-	if ((skb->dst = dst_pop(dst)) == NULL) {
+	if (((*pskb)->dst = dst_pop(dst)) == NULL) {
 		err = -EHOSTUNREACH;
 		goto error_nolock;
 	}
@@ -150,7 +151,7 @@ static int ah_output(struct sk_buff *skb)
 error:
 	spin_unlock_bh(&x->lock);
 error_nolock:
-	kfree_skb(skb);
+	kfree_skb(*pskb);
 	return err;
 }
 

net/ipv4/esp4.c

@@ -20,10 +20,10 @@ struct esp_decap_data {
 	__u8		proto;
 };
 
-int esp_output(struct sk_buff *skb)
+int esp_output(struct sk_buff **pskb)
 {
 	int err;
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = (*pskb)->dst;
 	struct xfrm_state *x  = dst->xfrm;
 	struct iphdr *iph, *top_iph;
 	struct ip_esp_hdr *esph;
@@ -42,28 +42,28 @@ int esp_output(struct sk_buff *skb)
 		char 		buf[60];
 	} tmp_iph;
 
-	/* First, if the skb is not checksummed, complete checksum. */
-	if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) {
-		err = -EINVAL;
-		goto error_nolock;
+	if ((*pskb)->ip_summed == CHECKSUM_HW) {
+		err = skb_checksum_help(pskb, 0);
+		if (err)
+			goto error_nolock;
 	}
 
 	spin_lock_bh(&x->lock);
-	err = xfrm_check_output(x, skb, AF_INET);
+	err = xfrm_check_output(x, *pskb, AF_INET);
 	if (err)
 		goto error;
 	err = -ENOMEM;
 
 	/* Strip IP header in transport mode. Save it. */
 	if (!x->props.mode) {
-		iph = skb->nh.iph;
+		iph = (*pskb)->nh.iph;
 		memcpy(&tmp_iph, iph, iph->ihl*4);
-		__skb_pull(skb, iph->ihl*4);
+		__skb_pull(*pskb, iph->ihl*4);
 	}
 	/* Now skb is pure payload to encrypt */
 
 	/* Round to block size */
-	clen = skb->len;
+	clen = (*pskb)->len;
 
 	esp = x->data;
 	alen = esp->auth.icv_trunc_len;
@@ -73,23 +73,23 @@ int esp_output(struct sk_buff *skb)
 	if (esp->conf.padlen)
 		clen = (clen + esp->conf.padlen-1)&~(esp->conf.padlen-1);
 
-	if ((nfrags = skb_cow_data(skb, clen-skb->len+alen, &trailer)) < 0)
+	if ((nfrags = skb_cow_data(*pskb, clen-(*pskb)->len+alen, &trailer)) < 0)
 		goto error;
 
 	/* Fill padding... */
 	do {
 		int i;
-		for (i=0; i<clen-skb->len - 2; i++)
+		for (i=0; i<clen-(*pskb)->len - 2; i++)
 			*(u8*)(trailer->tail + i) = i+1;
 	} while (0);
-	*(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2;
-	pskb_put(skb, trailer, clen - skb->len);
+	*(u8*)(trailer->tail + clen-(*pskb)->len - 2) = (clen - (*pskb)->len)-2;
+	pskb_put(*pskb, trailer, clen - (*pskb)->len);
 
 	encap = x->encap;
 
-	iph = skb->nh.iph;
+	iph = (*pskb)->nh.iph;
 	if (x->props.mode) {
-		top_iph = (struct iphdr*)skb_push(skb, x->props.header_len);
+		top_iph = (struct iphdr*)skb_push(*pskb, x->props.header_len);
 		esph = (struct ip_esp_hdr*)(top_iph+1);
 		if (encap && encap->encap_type) {
 			switch (encap->encap_type) {
@@ -121,7 +121,7 @@ int esp_output(struct sk_buff *skb)
 		top_iph->tos = iph->tos;	/* DS disclosed */
 		if (x->props.flags & XFRM_STATE_NOECN)
 			IP_ECN_clear(top_iph);
-		top_iph->tot_len = htons(skb->len + alen);
+		top_iph->tot_len = htons((*pskb)->len + alen);
 		top_iph->frag_off = iph->frag_off&htons(IP_DF);
 		if (!(top_iph->frag_off))
 			ip_select_ident(top_iph, dst, 0);
@@ -129,10 +129,10 @@ int esp_output(struct sk_buff *skb)
 		top_iph->check = 0;
 		top_iph->saddr = x->props.saddr.a4;
 		top_iph->daddr = x->id.daddr.a4;
-		memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options));
+		memset(&(IPCB(*pskb)->opt), 0, sizeof(struct ip_options));
 	} else {
-		esph = (struct ip_esp_hdr*)skb_push(skb, x->props.header_len);
-		top_iph = (struct iphdr*)skb_push(skb, iph->ihl*4);
+		esph = (struct ip_esp_hdr*)skb_push(*pskb, x->props.header_len);
+		top_iph = (struct iphdr*)skb_push(*pskb, iph->ihl*4);
 		memcpy(top_iph, &tmp_iph, iph->ihl*4);
 		if (encap && encap->encap_type) {
 			switch (encap->encap_type) {
@@ -159,7 +159,7 @@ int esp_output(struct sk_buff *skb)
 		} else
 			top_iph->protocol = IPPROTO_ESP;
 		iph = &tmp_iph.iph;
-		top_iph->tot_len = htons(skb->len + alen);
+		top_iph->tot_len = htons((*pskb)->len + alen);
 		top_iph->check = 0;
 		top_iph->frag_off = iph->frag_off;
 		*(u8*)(trailer->tail - 1) = iph->protocol;
@@ -169,7 +169,7 @@ int esp_output(struct sk_buff *skb)
 	if (encap && uh) {
 		uh->source = encap->encap_sport;
 		uh->dest = encap->encap_dport;
-		uh->len = htons(skb->len + alen - sizeof(struct iphdr));
+		uh->len = htons((*pskb)->len + alen - sizeof(struct iphdr));
 		uh->check = 0;
 	}
 
@@ -188,7 +188,7 @@ int esp_output(struct sk_buff *skb)
 			if (!sg)
 				goto error;
 		}
-		skb_to_sgvec(skb, sg, esph->enc_data+esp->conf.ivlen-skb->data, clen);
+		skb_to_sgvec(*pskb, sg, esph->enc_data+esp->conf.ivlen-(*pskb)->data, clen);
 		crypto_cipher_encrypt(tfm, sg, sg, clen);
 		if (unlikely(sg != sgbuf))
 			kfree(sg);
@@ -200,19 +200,19 @@ int esp_output(struct sk_buff *skb)
 	}
 
 	if (esp->auth.icv_full_len) {
-		esp->auth.icv(esp, skb, (u8*)esph-skb->data,
+		esp->auth.icv(esp, *pskb, (u8*)esph-(*pskb)->data,
 		              sizeof(struct ip_esp_hdr) + esp->conf.ivlen+clen, trailer->tail);
-		pskb_put(skb, trailer, alen);
+		pskb_put(*pskb, trailer, alen);
 	}
 
 	ip_send_check(top_iph);
 
-	skb->nh.raw = skb->data;
+	(*pskb)->nh.raw = (*pskb)->data;
 
-	x->curlft.bytes += skb->len;
+	x->curlft.bytes += (*pskb)->len;
 	x->curlft.packets++;
 	spin_unlock_bh(&x->lock);
-	if ((skb->dst = dst_pop(dst)) == NULL) {
+	if (((*pskb)->dst = dst_pop(dst)) == NULL) {
 		err = -EHOSTUNREACH;
 		goto error_nolock;
 	}
@@ -221,7 +221,7 @@ int esp_output(struct sk_buff *skb)
 error:
 	spin_unlock_bh(&x->lock);
 error_nolock:
-	kfree_skb(skb);
+	kfree_skb(*pskb);
 	return err;
 }
 

net/ipv4/ip_output.c

@@ -223,8 +223,9 @@ int ip_finish_output(struct sk_buff *skb)
 		       ip_finish_output2);
 }
 
-int ip_mc_output(struct sk_buff *skb)
+int ip_mc_output(struct sk_buff **pskb)
 {
+	struct sk_buff *skb = *pskb;
 	struct sock *sk = skb->sk;
 	struct rtable *rt = (struct rtable*)skb->dst;
 	struct net_device *dev = rt->u.dst.dev;
@@ -283,8 +284,10 @@ int ip_mc_output(struct sk_buff *skb)
 		return ip_finish_output(skb);
 }
 
-int ip_output(struct sk_buff *skb)
+int ip_output(struct sk_buff **pskb)
 {
+	struct sk_buff *skb = *pskb;
+
 	IP_INC_STATS(OutRequests);
 
 	if ((skb->len > dst_pmtu(skb->dst) || skb_shinfo(skb)->frag_list) &&

net/ipv4/ipcomp.c

@@ -143,10 +143,10 @@ static void ipcomp_tunnel_encap(struct xfrm_state *x, struct sk_buff *skb)
 	skb->nh.raw = skb->data;
 }
 
-static int ipcomp_output(struct sk_buff *skb)
+static int ipcomp_output(struct sk_buff **pskb)
 {
 	int err;
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = (*pskb)->dst;
 	struct xfrm_state *x = dst->xfrm;
 	struct iphdr *iph, *top_iph;
 	struct ip_comp_hdr *ipch;
@@ -157,25 +157,26 @@ static int ipcomp_output(struct sk_buff *skb)
 	} tmp_iph;
 	int hdr_len = 0;
 
-	if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) {
-		err = -EINVAL;
-		goto error_nolock;
+	if ((*pskb)->ip_summed == CHECKSUM_HW) {
+		err = skb_checksum_help(pskb, 0);
+		if (err)
+			goto error_nolock;
 	}
 
 	spin_lock_bh(&x->lock);
-	err = xfrm_check_output(x, skb, AF_INET);
+	err = xfrm_check_output(x, *pskb, AF_INET);
 	if (err)
 		goto error;
 
 	/* Don't bother compressing */
 	if (!x->props.mode) {
-		iph = skb->nh.iph;
+		iph = (*pskb)->nh.iph;
 		hdr_len = iph->ihl * 4;
 	}
-	if ((skb->len - hdr_len) < ipcd->threshold) {
+	if (((*pskb)->len - hdr_len) < ipcd->threshold) {
 		if (x->props.mode) {
-			ipcomp_tunnel_encap(x, skb);
-			iph = skb->nh.iph;
+			ipcomp_tunnel_encap(x, *pskb);
+			iph = (*pskb)->nh.iph;
 			iph->protocol = IPPROTO_IPIP;
 			ip_send_check(iph);
 		}
@@ -183,19 +184,19 @@ static int ipcomp_output(struct sk_buff *skb)
 	}
 
 	if (x->props.mode) 
-		ipcomp_tunnel_encap(x, skb);
+		ipcomp_tunnel_encap(x, *pskb);
 
-	if ((skb_is_nonlinear(skb) || skb_cloned(skb)) &&
-	    skb_linearize(skb, GFP_ATOMIC) != 0) {
+	if ((skb_is_nonlinear(*pskb) || skb_cloned(*pskb)) &&
+	    skb_linearize(*pskb, GFP_ATOMIC) != 0) {
 	    	err = -ENOMEM;
 	    	goto error;
 	}
 	
-	err = ipcomp_compress(x, skb);
+	err = ipcomp_compress(x, *pskb);
 	if (err) {
 		if (err == -EMSGSIZE) {
 			if (x->props.mode) {
-				iph = skb->nh.iph;
+				iph = (*pskb)->nh.iph;
 				iph->protocol = IPPROTO_IPIP;
 				ip_send_check(iph);
 			}
@@ -205,14 +206,14 @@ static int ipcomp_output(struct sk_buff *skb)
 	}
 
 	/* Install ipcomp header, convert into ipcomp datagram. */
-	iph = skb->nh.iph;
+	iph = (*pskb)->nh.iph;
 	memcpy(&tmp_iph, iph, iph->ihl * 4);
-	top_iph = (struct iphdr *)skb_push(skb, sizeof(struct ip_comp_hdr));
+	top_iph = (struct iphdr *)skb_push(*pskb, sizeof(struct ip_comp_hdr));
 	memcpy(top_iph, &tmp_iph, iph->ihl * 4);
 	iph = top_iph;
 	if (x->props.mode && (x->props.flags & XFRM_STATE_NOECN))
 		IP_ECN_clear(iph);
-	iph->tot_len = htons(skb->len);
+	iph->tot_len = htons((*pskb)->len);
 	iph->protocol = IPPROTO_COMP;
 	iph->check = 0;
 	ipch = (struct ip_comp_hdr *)((char *)iph + iph->ihl * 4);
@@ -220,14 +221,14 @@ static int ipcomp_output(struct sk_buff *skb)
 	ipch->flags = 0;
 	ipch->cpi = htons((u16 )ntohl(x->id.spi));
 	ip_send_check(iph);
-	skb->nh.raw = skb->data;
+	(*pskb)->nh.raw = (*pskb)->data;
 
 out_ok:
-	x->curlft.bytes += skb->len;
+	x->curlft.bytes += (*pskb)->len;
 	x->curlft.packets++;
 	spin_unlock_bh(&x->lock);
 	
-	if ((skb->dst = dst_pop(dst)) == NULL) {
+	if (((*pskb)->dst = dst_pop(dst)) == NULL) {
 		err = -EHOSTUNREACH;
 		goto error_nolock;
 	}
@@ -238,7 +239,7 @@ static int ipcomp_output(struct sk_buff *skb)
 error:
 	spin_unlock_bh(&x->lock);
 error_nolock:
-	kfree_skb(skb);
+	kfree_skb(*pskb);
 	goto out_exit;
 }
 

net/ipv4/netfilter/ip_fw_compat.c

@@ -69,7 +69,8 @@ fw_in(unsigned int hooknum,
 	/* Assume worse case: any hook could change packet */
 	(*pskb)->nfcache |= NFC_UNKNOWN | NFC_ALTERED;
 	if ((*pskb)->ip_summed == CHECKSUM_HW)
-		(*pskb)->ip_summed = CHECKSUM_NONE;
+		if (skb_checksum_help(pskb, (out == NULL)))
+			return NF_DROP;
 
 	switch (hooknum) {
 	case NF_IP_PRE_ROUTING:

net/ipv4/netfilter/ip_nat_standalone.c

@@ -85,7 +85,8 @@ ip_nat_fn(unsigned int hooknum,
 
 	/* If we had a hardware checksum before, it's now invalid */
 	if ((*pskb)->ip_summed == CHECKSUM_HW)
-		(*pskb)->ip_summed = CHECKSUM_NONE;
+		if (skb_checksum_help(pskb, (out == NULL)))
+			return NF_DROP;
 
 	ct = ip_conntrack_get(*pskb, &ctinfo);
 	/* Can't track?  It's not due to stress, or conntrack would

net/ipv4/netfilter/ipt_ECN.c

@@ -50,7 +50,7 @@ set_ect_ip(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
 
 /* Return 0 if there was an error. */
 static inline int
-set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
+set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo, int inward)
 {
 	struct tcphdr tcph;
 	u_int16_t diffs[2];
@@ -74,11 +74,15 @@ set_ect_tcp(struct sk_buff **pskb, const struct ipt_ECN_info *einfo)
 		if (!skb_ip_make_writable(pskb,
 					  (*pskb)->nh.iph->ihl*4+sizeof(tcph)))
 			return 0;
-		tcph.check = csum_fold(csum_partial((char *)diffs,
-		                                    sizeof(diffs),
-		                                    tcph.check^0xFFFF));
+		if ((*pskb)->ip_summed != CHECKSUM_HW)
+			tcph.check = csum_fold(csum_partial((char *)diffs,
+					       sizeof(diffs),
+					       tcph.check^0xFFFF));
 		memcpy((*pskb)->data + (*pskb)->nh.iph->ihl*4,
 		       &tcph, sizeof(tcph));
+		if ((*pskb)->ip_summed == CHECKSUM_HW)
+			if (skb_checksum_help(pskb, inward))
+				return 0;
 		(*pskb)->nfcache |= NFC_ALTERED;
 	}
 	return 1;
@@ -100,7 +104,7 @@ target(struct sk_buff **pskb,
 
 	if (einfo->operation & (IPT_ECN_OP_SET_ECE | IPT_ECN_OP_SET_CWR)
 	    && (*pskb)->nh.iph->protocol == IPPROTO_TCP)
-		if (!set_ect_tcp(pskb, einfo))
+		if (!set_ect_tcp(pskb, einfo, (out == NULL)))
 			return NF_DROP;
 
 	return IPT_CONTINUE;

net/ipv4/netfilter/ipt_TCPMSS.c

@@ -186,8 +186,9 @@ ipt_tcpmss_target(struct sk_buff **pskb,
 	       newmss);
 
  retmodified:
-	/* If we had a hardware checksum before, it's now invalid */
-	(*pskb)->ip_summed = CHECKSUM_NONE;
+	/* We never hw checksum SYN packets.  */
+	BUG_ON((*pskb)->ip_summed == CHECKSUM_HW);
+
 	(*pskb)->nfcache |= NFC_UNKNOWN | NFC_ALTERED;
 	return IPT_CONTINUE;
 }

net/ipv4/route.c

@@ -1347,8 +1347,10 @@ static void ipv4_link_failure(struct sk_buff *skb)
 		dst_set_expires(&rt->u.dst, 0);
 }
 
-static int ip_rt_bug(struct sk_buff *skb)
+static int ip_rt_bug(struct sk_buff **pskb)
 {
+	struct sk_buff *skb = *pskb;
+
 	printk(KERN_DEBUG "ip_rt_bug: %u.%u.%u.%u -> %u.%u.%u.%u, %s\n",
 		NIPQUAD(skb->nh.iph->saddr), NIPQUAD(skb->nh.iph->daddr),
 		skb->dev ? skb->dev->name : "?");

net/ipv4/xfrm4_tunnel.c

@@ -33,8 +33,9 @@ int xfrm4_tunnel_check_size(struct sk_buff *skb)
 	return ret;
 }
 
-static int ipip_output(struct sk_buff *skb)
+static int ipip_output(struct sk_buff **pskb)
 {
+	struct sk_buff *skb = *pskb;
 	struct dst_entry *dst = skb->dst;
 	struct xfrm_state *x = dst->xfrm;
 	struct iphdr *iph, *top_iph;

net/ipv6/ah6.c

@@ -144,11 +144,11 @@ static int ipv6_clear_mutable_options(struct sk_buff *skb, u16 *nh_offset, int d
 	return nexthdr;
 }
 
-int ah6_output(struct sk_buff *skb)
+int ah6_output(struct sk_buff **pskb)
 {
 	int err;
 	int hdr_len = sizeof(struct ipv6hdr);
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = (*pskb)->dst;
 	struct xfrm_state *x  = dst->xfrm;
 	struct ipv6hdr *iph = NULL;
 	struct ip_auth_hdr *ah;
@@ -156,54 +156,55 @@ int ah6_output(struct sk_buff *skb)
 	u16 nh_offset = 0;
 	u8 nexthdr;
 
-	if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) {
-		err = -EINVAL;
-		goto error_nolock;
+	if ((*pskb)->ip_summed == CHECKSUM_HW) {
+		err = skb_checksum_help(pskb, 0);
+		if (err)
+			goto error_nolock;
 	}
 
 	spin_lock_bh(&x->lock);
-	err = xfrm_check_output(x, skb, AF_INET6);
+	err = xfrm_check_output(x, *pskb, AF_INET6);
 	if (err)
 		goto error;
 
 	if (x->props.mode) {
-		iph = skb->nh.ipv6h;
-		skb->nh.ipv6h = (struct ipv6hdr*)skb_push(skb, x->props.header_len);
-		skb->nh.ipv6h->version = 6;
-		skb->nh.ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
-		skb->nh.ipv6h->nexthdr = IPPROTO_AH;
-		ipv6_addr_copy(&skb->nh.ipv6h->saddr,
+		iph = (*pskb)->nh.ipv6h;
+		(*pskb)->nh.ipv6h = (struct ipv6hdr*)skb_push(*pskb, x->props.header_len);
+		(*pskb)->nh.ipv6h->version = 6;
+		(*pskb)->nh.ipv6h->payload_len = htons((*pskb)->len - sizeof(struct ipv6hdr));
+		(*pskb)->nh.ipv6h->nexthdr = IPPROTO_AH;
+		ipv6_addr_copy(&(*pskb)->nh.ipv6h->saddr,
 			       (struct in6_addr *) &x->props.saddr);
-		ipv6_addr_copy(&skb->nh.ipv6h->daddr,
+		ipv6_addr_copy(&(*pskb)->nh.ipv6h->daddr,
 			       (struct in6_addr *) &x->id.daddr);
-		ah = (struct ip_auth_hdr*)(skb->nh.ipv6h+1);
+		ah = (struct ip_auth_hdr*)((*pskb)->nh.ipv6h+1);
 		ah->nexthdr = IPPROTO_IPV6;
 	} else {
-		hdr_len = skb->h.raw - skb->nh.raw;
+		hdr_len = (*pskb)->h.raw - (*pskb)->nh.raw;
 		iph = kmalloc(hdr_len, GFP_ATOMIC);
 		if (!iph) {
 			err = -ENOMEM;
 			goto error;
 		}
-		memcpy(iph, skb->data, hdr_len);
-		skb->nh.ipv6h = (struct ipv6hdr*)skb_push(skb, x->props.header_len);
-		memcpy(skb->nh.ipv6h, iph, hdr_len);
-		nexthdr = ipv6_clear_mutable_options(skb, &nh_offset, XFRM_POLICY_OUT);
+		memcpy(iph, (*pskb)->data, hdr_len);
+		(*pskb)->nh.ipv6h = (struct ipv6hdr*)skb_push(*pskb, x->props.header_len);
+		memcpy((*pskb)->nh.ipv6h, iph, hdr_len);
+		nexthdr = ipv6_clear_mutable_options(*pskb, &nh_offset, XFRM_POLICY_OUT);
 		if (nexthdr == 0)
 			goto error_free_iph;
 
-		skb->nh.raw[nh_offset] = IPPROTO_AH;
-		skb->nh.ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
-		ah = (struct ip_auth_hdr*)(skb->nh.raw+hdr_len);
-		skb->h.raw = (unsigned char*) ah;
+		(*pskb)->nh.raw[nh_offset] = IPPROTO_AH;
+		(*pskb)->nh.ipv6h->payload_len = htons((*pskb)->len - sizeof(struct ipv6hdr));
+		ah = (struct ip_auth_hdr*)((*pskb)->nh.raw+hdr_len);
+		(*pskb)->h.raw = (unsigned char*) ah;
 		ah->nexthdr = nexthdr;
 	}
 
-	skb->nh.ipv6h->priority    = 0;
-	skb->nh.ipv6h->flow_lbl[0] = 0;
-	skb->nh.ipv6h->flow_lbl[1] = 0;
-	skb->nh.ipv6h->flow_lbl[2] = 0;
-	skb->nh.ipv6h->hop_limit    = 0;
+	(*pskb)->nh.ipv6h->priority    = 0;
+	(*pskb)->nh.ipv6h->flow_lbl[0] = 0;
+	(*pskb)->nh.ipv6h->flow_lbl[1] = 0;
+	(*pskb)->nh.ipv6h->flow_lbl[2] = 0;
+	(*pskb)->nh.ipv6h->hop_limit    = 0;
 
 	ahp = x->data;
 	ah->hdrlen  = (XFRM_ALIGN8(sizeof(struct ipv6_auth_hdr) + 
@@ -212,29 +213,29 @@ int ah6_output(struct sk_buff *skb)
 	ah->reserved = 0;
 	ah->spi = x->id.spi;
 	ah->seq_no = htonl(++x->replay.oseq);
-	ahp->icv(ahp, skb, ah->auth_data);
+	ahp->icv(ahp, *pskb, ah->auth_data);
 
 	if (x->props.mode) {
-		skb->nh.ipv6h->hop_limit   = iph->hop_limit;
-		skb->nh.ipv6h->priority    = iph->priority; 	
-		skb->nh.ipv6h->flow_lbl[0] = iph->flow_lbl[0];
-		skb->nh.ipv6h->flow_lbl[1] = iph->flow_lbl[1];
-		skb->nh.ipv6h->flow_lbl[2] = iph->flow_lbl[2];
+		(*pskb)->nh.ipv6h->hop_limit   = iph->hop_limit;
+		(*pskb)->nh.ipv6h->priority    = iph->priority; 	
+		(*pskb)->nh.ipv6h->flow_lbl[0] = iph->flow_lbl[0];
+		(*pskb)->nh.ipv6h->flow_lbl[1] = iph->flow_lbl[1];
+		(*pskb)->nh.ipv6h->flow_lbl[2] = iph->flow_lbl[2];
 		if (x->props.flags & XFRM_STATE_NOECN)
-			IP6_ECN_clear(skb->nh.ipv6h);
+			IP6_ECN_clear((*pskb)->nh.ipv6h);
 	} else {
-		memcpy(skb->nh.ipv6h, iph, hdr_len);
-		skb->nh.raw[nh_offset] = IPPROTO_AH;
-		skb->nh.ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+		memcpy((*pskb)->nh.ipv6h, iph, hdr_len);
+		(*pskb)->nh.raw[nh_offset] = IPPROTO_AH;
+		(*pskb)->nh.ipv6h->payload_len = htons((*pskb)->len - sizeof(struct ipv6hdr));
 		kfree (iph);
 	}
 
-	skb->nh.raw = skb->data;
+	(*pskb)->nh.raw = (*pskb)->data;
 
-	x->curlft.bytes += skb->len;
+	x->curlft.bytes += (*pskb)->len;
 	x->curlft.packets++;
 	spin_unlock_bh(&x->lock);
-	if ((skb->dst = dst_pop(dst)) == NULL) {
+	if (((*pskb)->dst = dst_pop(dst)) == NULL) {
 		err = -EHOSTUNREACH;
 		goto error_nolock;
 	}
@@ -244,7 +245,7 @@ int ah6_output(struct sk_buff *skb)
 error:
 	spin_unlock_bh(&x->lock);
 error_nolock:
-	kfree_skb(skb);
+	kfree_skb(*pskb);
 	return err;
 }
 

net/ipv6/esp6.c

@@ -40,11 +40,11 @@
 
 #define MAX_SG_ONSTACK 4
 
-int esp6_output(struct sk_buff *skb)
+int esp6_output(struct sk_buff **pskb)
 {
 	int err;
 	int hdr_len = 0;
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = (*pskb)->dst;
 	struct xfrm_state *x  = dst->xfrm;
 	struct ipv6hdr *iph = NULL, *top_iph;
 	struct ipv6_esp_hdr *esph;
@@ -58,14 +58,14 @@ int esp6_output(struct sk_buff *skb)
 	u8 *prevhdr;
 	u8 nexthdr = 0;
 
-	/* First, if the skb is not checksummed, complete checksum. */
-	if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) {
-		err = -EINVAL;
-		goto error_nolock;
+	if ((*pskb)->ip_summed == CHECKSUM_HW) {
+		err = skb_checksum_help(pskb, 0);
+		if (err)
+			goto error_nolock;
 	}
 
 	spin_lock_bh(&x->lock);
-	err = xfrm_check_output(x, skb, AF_INET6);
+	err = xfrm_check_output(x, *pskb, AF_INET6);
 	if (err)
 		goto error;
 	err = -ENOMEM;
@@ -73,7 +73,7 @@ int esp6_output(struct sk_buff *skb)
 	/* Strip IP header in transport mode. Save it. */
 
 	if (!x->props.mode) {
-		hdr_len = ip6_find_1stfragopt(skb, &prevhdr);
+		hdr_len = ip6_find_1stfragopt(*pskb, &prevhdr);
 		nexthdr = *prevhdr;
 		*prevhdr = IPPROTO_ESP;
 		iph = kmalloc(hdr_len, GFP_ATOMIC);
@@ -81,14 +81,14 @@ int esp6_output(struct sk_buff *skb)
 			err = -ENOMEM;
 			goto error;
 		}
-		memcpy(iph, skb->nh.raw, hdr_len);
-		__skb_pull(skb, hdr_len);
+		memcpy(iph, (*pskb)->nh.raw, hdr_len);
+		__skb_pull(*pskb, hdr_len);
 	}
 
 	/* Now skb is pure payload to encrypt */
 
 	/* Round to block size */
-	clen = skb->len;
+	clen = (*pskb)->len;
 
 	esp = x->data;
 	alen = esp->auth.icv_trunc_len;
@@ -98,7 +98,7 @@ int esp6_output(struct sk_buff *skb)
 	if (esp->conf.padlen)
 		clen = (clen + esp->conf.padlen-1)&~(esp->conf.padlen-1);
 
-	if ((nfrags = skb_cow_data(skb, clen-skb->len+alen, &trailer)) < 0) {
+	if ((nfrags = skb_cow_data(*pskb, clen-(*pskb)->len+alen, &trailer)) < 0) {
 		if (!x->props.mode && iph) kfree(iph);
 		goto error;
 	}
@@ -106,15 +106,15 @@ int esp6_output(struct sk_buff *skb)
 	/* Fill padding... */
 	do {
 		int i;
-		for (i=0; i<clen-skb->len - 2; i++)
+		for (i=0; i<clen-(*pskb)->len - 2; i++)
 			*(u8*)(trailer->tail + i) = i+1;
 	} while (0);
-	*(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2;
-	pskb_put(skb, trailer, clen - skb->len);
+	*(u8*)(trailer->tail + clen-(*pskb)->len - 2) = (clen - (*pskb)->len)-2;
+	pskb_put(*pskb, trailer, clen - (*pskb)->len);
 
 	if (x->props.mode) {
-		iph = skb->nh.ipv6h;
-		top_iph = (struct ipv6hdr*)skb_push(skb, x->props.header_len);
+		iph = (*pskb)->nh.ipv6h;
+		top_iph = (struct ipv6hdr*)skb_push(*pskb, x->props.header_len);
 		esph = (struct ipv6_esp_hdr*)(top_iph+1);
 		*(u8*)(trailer->tail - 1) = IPPROTO_IPV6;
 		top_iph->version = 6;
@@ -125,19 +125,19 @@ int esp6_output(struct sk_buff *skb)
 		if (x->props.flags & XFRM_STATE_NOECN)
 			IP6_ECN_clear(top_iph);
 		top_iph->nexthdr = IPPROTO_ESP;
-		top_iph->payload_len = htons(skb->len + alen - sizeof(struct ipv6hdr));
+		top_iph->payload_len = htons((*pskb)->len + alen - sizeof(struct ipv6hdr));
 		top_iph->hop_limit = iph->hop_limit;
 		ipv6_addr_copy(&top_iph->saddr,
 			       (struct in6_addr *)&x->props.saddr);
 		ipv6_addr_copy(&top_iph->daddr,
 			       (struct in6_addr *)&x->id.daddr);
 	} else { 
-		esph = (struct ipv6_esp_hdr*)skb_push(skb, x->props.header_len);
-		skb->h.raw = (unsigned char*)esph;
-		top_iph = (struct ipv6hdr*)skb_push(skb, hdr_len);
+		esph = (struct ipv6_esp_hdr*)skb_push(*pskb, x->props.header_len);
+		(*pskb)->h.raw = (unsigned char*)esph;
+		top_iph = (struct ipv6hdr*)skb_push(*pskb, hdr_len);
 		memcpy(top_iph, iph, hdr_len);
 		kfree(iph);
-		top_iph->payload_len = htons(skb->len + alen - sizeof(struct ipv6hdr));
+		top_iph->payload_len = htons((*pskb)->len + alen - sizeof(struct ipv6hdr));
 		*(u8*)(trailer->tail - 1) = nexthdr;
 	}
 
@@ -156,7 +156,7 @@ int esp6_output(struct sk_buff *skb)
 			if (!sg)
 				goto error;
 		}
-		skb_to_sgvec(skb, sg, esph->enc_data+esp->conf.ivlen-skb->data, clen);
+		skb_to_sgvec(*pskb, sg, esph->enc_data+esp->conf.ivlen-(*pskb)->data, clen);
 		crypto_cipher_encrypt(tfm, sg, sg, clen);
 		if (unlikely(sg != sgbuf))
 			kfree(sg);
@@ -168,17 +168,17 @@ int esp6_output(struct sk_buff *skb)
 	}
 
 	if (esp->auth.icv_full_len) {
-		esp->auth.icv(esp, skb, (u8*)esph-skb->data,
+		esp->auth.icv(esp, *pskb, (u8*)esph-(*pskb)->data,
 			sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen+clen, trailer->tail);
-		pskb_put(skb, trailer, alen);
+		pskb_put(*pskb, trailer, alen);
 	}
 
-	skb->nh.raw = skb->data;
+	(*pskb)->nh.raw = (*pskb)->data;
 
-	x->curlft.bytes += skb->len;
+	x->curlft.bytes += (*pskb)->len;
 	x->curlft.packets++;
 	spin_unlock_bh(&x->lock);
-	if ((skb->dst = dst_pop(dst)) == NULL) {
+	if (((*pskb)->dst = dst_pop(dst)) == NULL) {
 		err = -EHOSTUNREACH;
 		goto error_nolock;
 	}
@@ -187,7 +187,7 @@ int esp6_output(struct sk_buff *skb)
 error:
 	spin_unlock_bh(&x->lock);
 error_nolock:
-	kfree_skb(skb);
+	kfree_skb(*pskb);
 	return err;
 }
 

net/ipv6/ip6_output.c

@@ -55,7 +55,7 @@
 #include <net/icmp.h>
 #include <net/xfrm.h>
 
-static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*));
+static int ip6_fragment(struct sk_buff **pskb, int (*output)(struct sk_buff**));
 
 static __inline__ void ipv6_select_ident(struct sk_buff *skb, struct frag_hdr *fhdr)
 {
@@ -107,8 +107,9 @@ static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
 }
 
 
-int ip6_output2(struct sk_buff *skb)
+int ip6_output2(struct sk_buff **pskb)
 {
+	struct sk_buff *skb = *pskb;
 	struct dst_entry *dst = skb->dst;
 	struct net_device *dev = dst->dev;
 
@@ -144,12 +145,14 @@ int ip6_output2(struct sk_buff *skb)
 	return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb,NULL, skb->dev,ip6_output_finish);
 }
 
-int ip6_output(struct sk_buff *skb)
+int ip6_output(struct sk_buff **pskb)
 {
+	struct sk_buff *skb = *pskb;
+
 	if ((skb->len > dst_pmtu(skb->dst) || skb_shinfo(skb)->frag_list))
-		return ip6_fragment(skb, ip6_output2);
+		return ip6_fragment(pskb, ip6_output2);
 	else
-		return ip6_output2(skb);
+		return ip6_output2(pskb);
 }
 
 #ifdef CONFIG_NETFILTER
@@ -513,11 +516,11 @@ int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
 	return offset;
 }
 
-static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*))
+static int ip6_fragment(struct sk_buff **pskb, int (*output)(struct sk_buff**))
 {
 	struct net_device *dev;
+	struct sk_buff *frag, *skb = *pskb;
 	struct rt6_info *rt = (struct rt6_info*)skb->dst;
-	struct sk_buff *frag;
 	struct ipv6hdr *tmp_hdr;
 	struct frag_hdr *fh;
 	unsigned int mtu, hlen, left, len;
@@ -604,11 +607,13 @@ static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*))
 				frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr));
 				ip6_copy_metadata(frag, skb);
 			}
-			err = output(skb);
-
-			if (err || !frag)
+			err = output(pskb);
+			if (err || !frag) {
+				if (unlikely(skb != *pskb))
+					skb = *pskb;
 				break;
-
+			}
+			
 			skb = frag;
 			frag = skb->next;
 			skb->next = NULL;
@@ -721,7 +726,7 @@ static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*))
 
 		IP6_INC_STATS(FragCreates);
 
-		err = output(frag);
+		err = output(&frag);
 		if (err)
 			goto fail;
 	}

net/ipv6/ipcomp6.c

@@ -118,10 +118,10 @@ static int ipcomp6_input(struct xfrm_state *x, struct xfrm_decap_state *decap, s
 	return err;
 }
 
-static int ipcomp6_output(struct sk_buff *skb)
+static int ipcomp6_output(struct sk_buff **pskb)
 {
 	int err;
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = (*pskb)->dst;
 	struct xfrm_state *x = dst->xfrm;
 	struct ipv6hdr *tmp_iph = NULL, *iph, *top_iph;
 	int hdr_len = 0;
@@ -132,54 +132,55 @@ static int ipcomp6_output(struct sk_buff *skb)
 	int plen, dlen;
 	u8 *start, *scratch = ipcd->scratch;
 
-	if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) {
-		err = -EINVAL;
-		goto error_nolock;
+	if ((*pskb)->ip_summed == CHECKSUM_HW) {
+		err = skb_checksum_help(pskb, 0);
+		if (err)
+			goto error_nolock;
 	}
 
 	spin_lock_bh(&x->lock);
 
-	err = xfrm_check_output(x, skb, AF_INET6);
+	err = xfrm_check_output(x, *pskb, AF_INET6);
 	if (err)
 		goto error;
 
 	if (x->props.mode) {
 		hdr_len = sizeof(struct ipv6hdr);
 		nexthdr = IPPROTO_IPV6;
-		iph = skb->nh.ipv6h;
-		top_iph = (struct ipv6hdr *)skb_push(skb, sizeof(struct ipv6hdr));
+		iph = (*pskb)->nh.ipv6h;
+		top_iph = (struct ipv6hdr *)skb_push(*pskb, sizeof(struct ipv6hdr));
 		top_iph->version = 6;
 		top_iph->priority = iph->priority;
 		top_iph->flow_lbl[0] = iph->flow_lbl[0];
 		top_iph->flow_lbl[1] = iph->flow_lbl[1];
 		top_iph->flow_lbl[2] = iph->flow_lbl[2];
 		top_iph->nexthdr = IPPROTO_IPV6; /* initial */
-		top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
+		top_iph->payload_len = htons((*pskb)->len - sizeof(struct ipv6hdr));
 		top_iph->hop_limit = iph->hop_limit;
 		memcpy(&top_iph->saddr, (struct in6_addr *)&x->props.saddr, sizeof(struct in6_addr));
 		memcpy(&top_iph->daddr, (struct in6_addr *)&x->id.daddr, sizeof(struct in6_addr));
-		skb->nh.raw = skb->data; /* == top_iph */
-		skb->h.raw = skb->nh.raw + hdr_len;
+		(*pskb)->nh.raw = (*pskb)->data; /* == top_iph */
+		(*pskb)->h.raw = (*pskb)->nh.raw + hdr_len;
 	} else {
-		hdr_len = ip6_find_1stfragopt(skb, &prevhdr);
+		hdr_len = ip6_find_1stfragopt(*pskb, &prevhdr);
 		nexthdr = *prevhdr;
 	}
 
 	/* check whether datagram len is larger than threshold */
-	if ((skb->len - hdr_len) < ipcd->threshold) {
+	if (((*pskb)->len - hdr_len) < ipcd->threshold) {
 		goto out_ok;
 	}
 
-	if ((skb_is_nonlinear(skb) || skb_cloned(skb)) &&
-		skb_linearize(skb, GFP_ATOMIC) != 0) {
+	if ((skb_is_nonlinear(*pskb) || skb_cloned(*pskb)) &&
+		skb_linearize(*pskb, GFP_ATOMIC) != 0) {
 		err = -ENOMEM;
 		goto error;
 	}
 
 	/* compression */
-	plen = skb->len - hdr_len;
+	plen = (*pskb)->len - hdr_len;
 	dlen = IPCOMP_SCRATCH_SIZE;
-	start = skb->data + hdr_len;
+	start = (*pskb)->data + hdr_len;
 
 	err = crypto_comp_compress(ipcd->tfm, start, plen, scratch, &dlen);
 	if (err) {
@@ -189,7 +190,7 @@ static int ipcomp6_output(struct sk_buff *skb)
 		goto out_ok;
 	}
 	memcpy(start, scratch, dlen);
-	pskb_trim(skb, hdr_len+dlen);
+	pskb_trim(*pskb, hdr_len+dlen);
 
 	/* insert ipcomp header and replace datagram */
 	tmp_iph = kmalloc(hdr_len, GFP_ATOMIC);
@@ -197,16 +198,16 @@ static int ipcomp6_output(struct sk_buff *skb)
 		err = -ENOMEM;
 		goto error;
 	}
-	memcpy(tmp_iph, skb->nh.raw, hdr_len);
-	top_iph = (struct ipv6hdr*)skb_push(skb, sizeof(struct ipv6_comp_hdr));
+	memcpy(tmp_iph, (*pskb)->nh.raw, hdr_len);
+	top_iph = (struct ipv6hdr*)skb_push(*pskb, sizeof(struct ipv6_comp_hdr));
 	memcpy(top_iph, tmp_iph, hdr_len);
 	kfree(tmp_iph);
 
 	if (x->props.mode && (x->props.flags & XFRM_STATE_NOECN))
 		IP6_ECN_clear(top_iph);
-	top_iph->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
-	skb->nh.raw = skb->data; /* top_iph */
-	ip6_find_1stfragopt(skb, &prevhdr); 
+	top_iph->payload_len = htons((*pskb)->len - sizeof(struct ipv6hdr));
+	(*pskb)->nh.raw = (*pskb)->data; /* top_iph */
+	ip6_find_1stfragopt(*pskb, &prevhdr); 
 	*prevhdr = IPPROTO_COMP;
 
 	ipch = (struct ipv6_comp_hdr *)((unsigned char *)top_iph + hdr_len);
@@ -214,13 +215,13 @@ static int ipcomp6_output(struct sk_buff *skb)
 	ipch->flags = 0;
 	ipch->cpi = htons((u16 )ntohl(x->id.spi));
 
-	skb->h.raw = (unsigned char*)ipch;
+	(*pskb)->h.raw = (unsigned char*)ipch;
 out_ok:
-	x->curlft.bytes += skb->len;
+	x->curlft.bytes += (*pskb)->len;
 	x->curlft.packets++;
 	spin_unlock_bh(&x->lock);
 
-	if ((skb->dst = dst_pop(dst)) == NULL) {
+	if (((*pskb)->dst = dst_pop(dst)) == NULL) {
 		err = -EHOSTUNREACH;
 		goto error_nolock;
 	}
@@ -231,7 +232,7 @@ static int ipcomp6_output(struct sk_buff *skb)
 error:
 	spin_unlock_bh(&x->lock);
 error_nolock:
-	kfree_skb(skb);
+	kfree_skb(*pskb);
 	goto out_exit;
 }
 

net/ipv6/route.c

@@ -87,6 +87,7 @@ static void		ip6_dst_destroy(struct dst_entry *);
 static int		 ip6_dst_gc(void);
 
 static int		ip6_pkt_discard(struct sk_buff *skb);
+static int		ip6_pkt_discard_out(struct sk_buff **pskb);
 static void		ip6_link_failure(struct sk_buff *skb);
 static void		ip6_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
 
@@ -113,7 +114,7 @@ struct rt6_info ip6_null_entry = {
 			.error		= -ENETUNREACH,
 			.metrics	= { [RTAX_HOPLIMIT - 1] = 255, },
 			.input		= ip6_pkt_discard,
-			.output		= ip6_pkt_discard,
+			.output		= ip6_pkt_discard_out,
 			.ops		= &ip6_dst_ops,
 			.path		= (struct dst_entry*)&ip6_null_entry,
 		}
@@ -576,7 +577,7 @@ static struct dst_entry *ndisc_dst_gc_list;
 struct dst_entry *ndisc_dst_alloc(struct net_device *dev, 
 				  struct neighbour *neigh,
 				  struct in6_addr *addr,
-				  int (*output)(struct sk_buff *))
+				  int (*output)(struct sk_buff **))
 {
 	struct rt6_info *rt = ip6_dst_alloc();
 
@@ -778,7 +779,7 @@ int ip6_route_add(struct in6_rtmsg *rtmsg, struct nlmsghdr *nlh, void *_rtattr)
 			dev_put(dev);
 		dev = &loopback_dev;
 		dev_hold(dev);
-		rt->u.dst.output = ip6_pkt_discard;
+		rt->u.dst.output = ip6_pkt_discard_out;
 		rt->u.dst.input = ip6_pkt_discard;
 		rt->u.dst.error = -ENETUNREACH;
 		rt->rt6i_flags = RTF_REJECT|RTF_NONEXTHOP;
@@ -1278,6 +1279,11 @@ int ip6_pkt_discard(struct sk_buff *skb)
 	return 0;
 }
 
+int ip6_pkt_discard_out(struct sk_buff **pskb)
+{
+	return ip6_pkt_discard(*pskb);
+}
+
 /*
  *	Add address
  */