Commit f61944ef authored by Herbert Xu's avatar Herbert Xu Committed by David S. Miller
Browse files

[IPV6]: Make ipv6_frag_rcv return the same packet 



This patch implements the same change taht was done to ip_defrag.  It
makes ipv6_frag_rcv return the last packet received of a train of fragments
rather than the head of that sequence.

This allows us to get rid of the sk_buff ** argument later.

Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 3db05fea

net/ipv6/reassembly.c

+40 −17
Original line number Diff line number Diff line
@@ -42,6 +42,7 @@ 
#include <linux/icmpv6.h>

#include <linux/random.h>

#include <linux/jhash.h>

#include <linux/skbuff.h>



#include <net/sock.h>

#include <net/snmp.h>
@@ -107,6 +108,9 @@ static u32 ip6_frag_hash_rnd; 
static LIST_HEAD(ip6_frag_lru_list);

int ip6_frag_nqueues = 0;



static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev,

			  struct net_device *dev);



static __inline__ void __fq_unlink(struct frag_queue *fq)

{

	hlist_del(&fq->list);
@@ -420,10 +424,11 @@ fq_find(__be32 id, struct in6_addr *src, struct in6_addr *dst, 
}





static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,

static int ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb,

			   struct frag_hdr *fhdr, int nhoff)

{

	struct sk_buff *prev, *next;

	struct net_device *dev;

	int offset, end;



	if (fq->last_in & COMPLETE)
@@ -439,7 +444,7 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, 
		icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,

				  ((u8 *)&fhdr->frag_off -

				   skb_network_header(skb)));

		return;

		return -1;

	}



	if (skb->ip_summed == CHECKSUM_COMPLETE) {
@@ -471,7 +476,7 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, 
					 IPSTATS_MIB_INHDRERRORS);

			icmpv6_param_prob(skb, ICMPV6_HDR_FIELD,

					  offsetof(struct ipv6hdr, payload_len));

			return;

			return -1;

		}

		if (end > fq->len) {

			/* Some bits beyond end -> corruption. */
@@ -564,9 +569,11 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, 
	else

		fq->fragments = skb;



	if (skb->dev)

		fq->iif = skb->dev->ifindex;

	dev = skb->dev;

	if (dev) {

		fq->iif = dev->ifindex;

		skb->dev = NULL;

	}

	fq->stamp = skb->tstamp;

	fq->meat += skb->len;

	atomic_add(skb->truesize, &ip6_frag_mem);
@@ -578,14 +585,19 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, 
		fq->nhoffset = nhoff;

		fq->last_in |= FIRST_IN;

	}



	if (fq->last_in == (FIRST_IN | LAST_IN) && fq->meat == fq->len)

		return ip6_frag_reasm(fq, prev, dev);



	write_lock(&ip6_frag_lock);

	list_move_tail(&fq->lru_list, &ip6_frag_lru_list);

	write_unlock(&ip6_frag_lock);

	return;

	return -1;



err:

	IP6_INC_STATS(ip6_dst_idev(skb->dst), IPSTATS_MIB_REASMFAILS);

	kfree_skb(skb);

	return -1;

}



/*
@@ -597,7 +609,7 @@ static void ip6_frag_queue(struct frag_queue *fq, struct sk_buff *skb, 
 *	queue is eligible for reassembly i.e. it is not COMPLETE,

 *	the last and the first frames arrived and all the bits are here.

 */

static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in,

static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff *prev,

			  struct net_device *dev)

{

	struct sk_buff *fp, *head = fq->fragments;
@@ -606,6 +618,24 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in, 


	fq_kill(fq);



	/* Make the one we just received the head. */

	if (prev) {

		head = prev->next;

		fp = skb_clone(head, GFP_ATOMIC);



		if (!fp)

			goto out_oom;



		fp->next = head->next;

		prev->next = fp;



		skb_morph(head, fq->fragments);

		head->next = fq->fragments->next;



		kfree_skb(fq->fragments);

		fq->fragments = head;

	}



	BUG_TRAP(head != NULL);

	BUG_TRAP(FRAG6_CB(head)->offset == 0);
@@ -674,8 +704,6 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in, 
	ipv6_hdr(head)->payload_len = htons(payload_len);

	IP6CB(head)->nhoff = nhoff;



	*skb_in = head;



	/* Yes, and fold redundant checksum back. 8) */

	if (head->ip_summed == CHECKSUM_COMPLETE)

		head->csum = csum_partial(skb_network_header(head),
@@ -705,7 +733,6 @@ static int ip6_frag_reasm(struct frag_queue *fq, struct sk_buff **skb_in, 
static int ipv6_frag_rcv(struct sk_buff **skbp)

{

	struct sk_buff *skb = *skbp;

	struct net_device *dev = skb->dev;

	struct frag_hdr *fhdr;

	struct frag_queue *fq;

	struct ipv6hdr *hdr = ipv6_hdr(skb);
@@ -744,15 +771,11 @@ static int ipv6_frag_rcv(struct sk_buff **skbp) 


	if ((fq = fq_find(fhdr->identification, &hdr->saddr, &hdr->daddr,

			  ip6_dst_idev(skb->dst))) != NULL) {

		int ret = -1;

		int ret;



		spin_lock(&fq->lock);



		ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff);



		if (fq->last_in == (FIRST_IN|LAST_IN) &&

		    fq->meat == fq->len)

			ret = ip6_frag_reasm(fq, skbp, dev);

		ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff);



		spin_unlock(&fq->lock);

		fq_put(fq, NULL);