static int ipv6_frag_rcv(struct sk_buff *skb)
{
struct frag_hdr *fhdr;
struct frag_queue *fq;
const struct ipv6hdr *hdr = ipv6_hdr(skb);
struct net *net = dev_net(skb_dst(skb)->dev);
int evicted;
IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMREQDS);
/* Jumbo payload inhibits frag. header */
if (hdr->payload_len==0)
goto fail_hdr;
if (!pskb_may_pull(skb, (skb_transport_offset(skb) +
sizeof(struct frag_hdr))))
goto fail_hdr;
hdr = ipv6_hdr(skb);
fhdr = (struct frag_hdr *)skb_transport_header(skb);
if (!(fhdr->frag_off & htons(0xFFF9))) {
/* It is not a fragmented frame */
skb->transport_header += sizeof(struct frag_hdr);
IP6_INC_STATS_BH(net,
ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMOKS);
IP6CB(skb)->nhoff = (u8 *)fhdr - skb_network_header(skb);
return 1;
}
evicted = inet_frag_evictor(&net->ipv6.frags, &ip6_frags, false);
if (evicted)
IP6_ADD_STATS_BH(net, ip6_dst_idev(skb_dst(skb)),
IPSTATS_MIB_REASMFAILS, evicted);
fq = fq_find(net, fhdr->identification, &hdr->saddr, &hdr->daddr,
ip6_frag_ecn(hdr));
if (fq != NULL) {
int ret;
spin_lock(&fq->q.lock);
ret = ip6_frag_queue(fq, skb, fhdr, IP6CB(skb)->nhoff);
spin_unlock(&fq->q.lock);
inet_frag_put(&fq->q, &ip6_frags);
return ret;
}
IP6_INC_STATS_BH(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_REASMFAILS);
kfree_skb(skb);
return -1;
fail_hdr:
IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INHDRERRORS);
icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, skb_network_header_len(skb));
return -1;
}
/* Memory limiting on fragments. Evictor trashes the oldest
* fragment queue until we are back under the threshold.
*/
static void ip_evictor(struct net *net)
{
int evicted;
evicted = inet_frag_evictor(&net->ipv4.frags, &ip4_frags, false);
if (evicted)
IP_ADD_STATS_BH(net, IPSTATS_MIB_REASMFAILS, evicted);
}
static void ip6_evictor(struct net *net, struct inet6_dev *idev)
{
int evicted;
evicted = inet_frag_evictor(&net->ipv6.frags, &ip6_frags);
if (evicted)
IP6_ADD_STATS_BH(net, idev, IPSTATS_MIB_REASMFAILS, evicted);
}
