From f61944efdf0d2569721ed6d7b0445e9f1214b295 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Mon, 15 Oct 2007 01:28:47 -0700 Subject: [PATCH] [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: Herbert Xu Signed-off-by: David S. Miller --- net/ipv6/reassembly.c | 57 ++++++++++++++++++++++++++++++------------- 1 file changed, 40 insertions(+), 17 deletions(-) diff --git a/net/ipv6/reassembly.c b/net/ipv6/reassembly.c index 31601c9935..fa1055b669 100644 --- a/net/ipv6/reassembly.c +++ b/net/ipv6/reassembly.c @@ -42,6 +42,7 @@ #include #include #include +#include #include #include @@ -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; - skb->dev = NULL; + 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 @@ err: * 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 @@ out_fail: 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); -- 2.39.2