[NET]: Replace CHECKSUM_HW by CHECKSUM_PARTIAL/CHECKSUM_COMPLETE
[linux-2.6.git] / net / ipv6 / ip6_output.c
1 /*
2  *      IPv6 output functions
3  *      Linux INET6 implementation 
4  *
5  *      Authors:
6  *      Pedro Roque             <roque@di.fc.ul.pt>     
7  *
8  *      $Id: ip6_output.c,v 1.34 2002/02/01 22:01:04 davem Exp $
9  *
10  *      Based on linux/net/ipv4/ip_output.c
11  *
12  *      This program is free software; you can redistribute it and/or
13  *      modify it under the terms of the GNU General Public License
14  *      as published by the Free Software Foundation; either version
15  *      2 of the License, or (at your option) any later version.
16  *
17  *      Changes:
18  *      A.N.Kuznetsov   :       airthmetics in fragmentation.
19  *                              extension headers are implemented.
20  *                              route changes now work.
21  *                              ip6_forward does not confuse sniffers.
22  *                              etc.
23  *
24  *      H. von Brand    :       Added missing #include <linux/string.h>
25  *      Imran Patel     :       frag id should be in NBO
26  *      Kazunori MIYAZAWA @USAGI
27  *                      :       add ip6_append_data and related functions
28  *                              for datagram xmit
29  */
30
31 #include <linux/errno.h>
32 #include <linux/types.h>
33 #include <linux/string.h>
34 #include <linux/socket.h>
35 #include <linux/net.h>
36 #include <linux/netdevice.h>
37 #include <linux/if_arp.h>
38 #include <linux/in6.h>
39 #include <linux/tcp.h>
40 #include <linux/route.h>
41 #include <linux/module.h>
42
43 #include <linux/netfilter.h>
44 #include <linux/netfilter_ipv6.h>
45
46 #include <net/sock.h>
47 #include <net/snmp.h>
48
49 #include <net/ipv6.h>
50 #include <net/ndisc.h>
51 #include <net/protocol.h>
52 #include <net/ip6_route.h>
53 #include <net/addrconf.h>
54 #include <net/rawv6.h>
55 #include <net/icmp.h>
56 #include <net/xfrm.h>
57 #include <net/checksum.h>
58
59 static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *));
60
61 static __inline__ void ipv6_select_ident(struct sk_buff *skb, struct frag_hdr *fhdr)
62 {
63         static u32 ipv6_fragmentation_id = 1;
64         static DEFINE_SPINLOCK(ip6_id_lock);
65
66         spin_lock_bh(&ip6_id_lock);
67         fhdr->identification = htonl(ipv6_fragmentation_id);
68         if (++ipv6_fragmentation_id == 0)
69                 ipv6_fragmentation_id = 1;
70         spin_unlock_bh(&ip6_id_lock);
71 }
72
73 static inline int ip6_output_finish(struct sk_buff *skb)
74 {
75
76         struct dst_entry *dst = skb->dst;
77         struct hh_cache *hh = dst->hh;
78
79         if (hh) {
80                 int hh_alen;
81
82                 read_lock_bh(&hh->hh_lock);
83                 hh_alen = HH_DATA_ALIGN(hh->hh_len);
84                 memcpy(skb->data - hh_alen, hh->hh_data, hh_alen);
85                 read_unlock_bh(&hh->hh_lock);
86                 skb_push(skb, hh->hh_len);
87                 return hh->hh_output(skb);
88         } else if (dst->neighbour)
89                 return dst->neighbour->output(skb);
90
91         IP6_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
92         kfree_skb(skb);
93         return -EINVAL;
94
95 }
96
97 /* dev_loopback_xmit for use with netfilter. */
98 static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
99 {
100         newskb->mac.raw = newskb->data;
101         __skb_pull(newskb, newskb->nh.raw - newskb->data);
102         newskb->pkt_type = PACKET_LOOPBACK;
103         newskb->ip_summed = CHECKSUM_UNNECESSARY;
104         BUG_TRAP(newskb->dst);
105
106         netif_rx(newskb);
107         return 0;
108 }
109
110
111 static int ip6_output2(struct sk_buff *skb)
112 {
113         struct dst_entry *dst = skb->dst;
114         struct net_device *dev = dst->dev;
115
116         skb->protocol = htons(ETH_P_IPV6);
117         skb->dev = dev;
118
119         if (ipv6_addr_is_multicast(&skb->nh.ipv6h->daddr)) {
120                 struct ipv6_pinfo* np = skb->sk ? inet6_sk(skb->sk) : NULL;
121
122                 if (!(dev->flags & IFF_LOOPBACK) && (!np || np->mc_loop) &&
123                     ipv6_chk_mcast_addr(dev, &skb->nh.ipv6h->daddr,
124                                 &skb->nh.ipv6h->saddr)) {
125                         struct sk_buff *newskb = skb_clone(skb, GFP_ATOMIC);
126
127                         /* Do not check for IFF_ALLMULTI; multicast routing
128                            is not supported in any case.
129                          */
130                         if (newskb)
131                                 NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, newskb, NULL,
132                                         newskb->dev,
133                                         ip6_dev_loopback_xmit);
134
135                         if (skb->nh.ipv6h->hop_limit == 0) {
136                                 IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
137                                 kfree_skb(skb);
138                                 return 0;
139                         }
140                 }
141
142                 IP6_INC_STATS(IPSTATS_MIB_OUTMCASTPKTS);
143         }
144
145         return NF_HOOK(PF_INET6, NF_IP6_POST_ROUTING, skb,NULL, skb->dev,ip6_output_finish);
146 }
147
148 int ip6_output(struct sk_buff *skb)
149 {
150         if ((skb->len > dst_mtu(skb->dst) && !skb_is_gso(skb)) ||
151                                 dst_allfrag(skb->dst))
152                 return ip6_fragment(skb, ip6_output2);
153         else
154                 return ip6_output2(skb);
155 }
156
157 /*
158  *      xmit an sk_buff (used by TCP)
159  */
160
161 int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
162              struct ipv6_txoptions *opt, int ipfragok)
163 {
164         struct ipv6_pinfo *np = inet6_sk(sk);
165         struct in6_addr *first_hop = &fl->fl6_dst;
166         struct dst_entry *dst = skb->dst;
167         struct ipv6hdr *hdr;
168         u8  proto = fl->proto;
169         int seg_len = skb->len;
170         int hlimit, tclass;
171         u32 mtu;
172
173         if (opt) {
174                 int head_room;
175
176                 /* First: exthdrs may take lots of space (~8K for now)
177                    MAX_HEADER is not enough.
178                  */
179                 head_room = opt->opt_nflen + opt->opt_flen;
180                 seg_len += head_room;
181                 head_room += sizeof(struct ipv6hdr) + LL_RESERVED_SPACE(dst->dev);
182
183                 if (skb_headroom(skb) < head_room) {
184                         struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
185                         kfree_skb(skb);
186                         skb = skb2;
187                         if (skb == NULL) {      
188                                 IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
189                                 return -ENOBUFS;
190                         }
191                         if (sk)
192                                 skb_set_owner_w(skb, sk);
193                 }
194                 if (opt->opt_flen)
195                         ipv6_push_frag_opts(skb, opt, &proto);
196                 if (opt->opt_nflen)
197                         ipv6_push_nfrag_opts(skb, opt, &proto, &first_hop);
198         }
199
200         hdr = skb->nh.ipv6h = (struct ipv6hdr*)skb_push(skb, sizeof(struct ipv6hdr));
201
202         /*
203          *      Fill in the IPv6 header
204          */
205
206         hlimit = -1;
207         if (np)
208                 hlimit = np->hop_limit;
209         if (hlimit < 0)
210                 hlimit = dst_metric(dst, RTAX_HOPLIMIT);
211         if (hlimit < 0)
212                 hlimit = ipv6_get_hoplimit(dst->dev);
213
214         tclass = -1;
215         if (np)
216                 tclass = np->tclass;
217         if (tclass < 0)
218                 tclass = 0;
219
220         *(u32 *)hdr = htonl(0x60000000 | (tclass << 20)) | fl->fl6_flowlabel;
221
222         hdr->payload_len = htons(seg_len);
223         hdr->nexthdr = proto;
224         hdr->hop_limit = hlimit;
225
226         ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
227         ipv6_addr_copy(&hdr->daddr, first_hop);
228
229         skb->priority = sk->sk_priority;
230
231         mtu = dst_mtu(dst);
232         if ((skb->len <= mtu) || ipfragok || skb_is_gso(skb)) {
233                 IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS);
234                 return NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, dst->dev,
235                                 dst_output);
236         }
237
238         if (net_ratelimit())
239                 printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n");
240         skb->dev = dst->dev;
241         icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
242         IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
243         kfree_skb(skb);
244         return -EMSGSIZE;
245 }
246
247 /*
248  *      To avoid extra problems ND packets are send through this
249  *      routine. It's code duplication but I really want to avoid
250  *      extra checks since ipv6_build_header is used by TCP (which
251  *      is for us performance critical)
252  */
253
254 int ip6_nd_hdr(struct sock *sk, struct sk_buff *skb, struct net_device *dev,
255                struct in6_addr *saddr, struct in6_addr *daddr,
256                int proto, int len)
257 {
258         struct ipv6_pinfo *np = inet6_sk(sk);
259         struct ipv6hdr *hdr;
260         int totlen;
261
262         skb->protocol = htons(ETH_P_IPV6);
263         skb->dev = dev;
264
265         totlen = len + sizeof(struct ipv6hdr);
266
267         hdr = (struct ipv6hdr *) skb_put(skb, sizeof(struct ipv6hdr));
268         skb->nh.ipv6h = hdr;
269
270         *(u32*)hdr = htonl(0x60000000);
271
272         hdr->payload_len = htons(len);
273         hdr->nexthdr = proto;
274         hdr->hop_limit = np->hop_limit;
275
276         ipv6_addr_copy(&hdr->saddr, saddr);
277         ipv6_addr_copy(&hdr->daddr, daddr);
278
279         return 0;
280 }
281
282 static int ip6_call_ra_chain(struct sk_buff *skb, int sel)
283 {
284         struct ip6_ra_chain *ra;
285         struct sock *last = NULL;
286
287         read_lock(&ip6_ra_lock);
288         for (ra = ip6_ra_chain; ra; ra = ra->next) {
289                 struct sock *sk = ra->sk;
290                 if (sk && ra->sel == sel &&
291                     (!sk->sk_bound_dev_if ||
292                      sk->sk_bound_dev_if == skb->dev->ifindex)) {
293                         if (last) {
294                                 struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
295                                 if (skb2)
296                                         rawv6_rcv(last, skb2);
297                         }
298                         last = sk;
299                 }
300         }
301
302         if (last) {
303                 rawv6_rcv(last, skb);
304                 read_unlock(&ip6_ra_lock);
305                 return 1;
306         }
307         read_unlock(&ip6_ra_lock);
308         return 0;
309 }
310
311 static inline int ip6_forward_finish(struct sk_buff *skb)
312 {
313         return dst_output(skb);
314 }
315
316 int ip6_forward(struct sk_buff *skb)
317 {
318         struct dst_entry *dst = skb->dst;
319         struct ipv6hdr *hdr = skb->nh.ipv6h;
320         struct inet6_skb_parm *opt = IP6CB(skb);
321         
322         if (ipv6_devconf.forwarding == 0)
323                 goto error;
324
325         if (!xfrm6_policy_check(NULL, XFRM_POLICY_FWD, skb)) {
326                 IP6_INC_STATS(IPSTATS_MIB_INDISCARDS);
327                 goto drop;
328         }
329
330         skb->ip_summed = CHECKSUM_NONE;
331
332         /*
333          *      We DO NOT make any processing on
334          *      RA packets, pushing them to user level AS IS
335          *      without ane WARRANTY that application will be able
336          *      to interpret them. The reason is that we
337          *      cannot make anything clever here.
338          *
339          *      We are not end-node, so that if packet contains
340          *      AH/ESP, we cannot make anything.
341          *      Defragmentation also would be mistake, RA packets
342          *      cannot be fragmented, because there is no warranty
343          *      that different fragments will go along one path. --ANK
344          */
345         if (opt->ra) {
346                 u8 *ptr = skb->nh.raw + opt->ra;
347                 if (ip6_call_ra_chain(skb, (ptr[2]<<8) + ptr[3]))
348                         return 0;
349         }
350
351         /*
352          *      check and decrement ttl
353          */
354         if (hdr->hop_limit <= 1) {
355                 /* Force OUTPUT device used as source address */
356                 skb->dev = dst->dev;
357                 icmpv6_send(skb, ICMPV6_TIME_EXCEED, ICMPV6_EXC_HOPLIMIT,
358                             0, skb->dev);
359                 IP6_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
360
361                 kfree_skb(skb);
362                 return -ETIMEDOUT;
363         }
364
365         if (!xfrm6_route_forward(skb)) {
366                 IP6_INC_STATS(IPSTATS_MIB_INDISCARDS);
367                 goto drop;
368         }
369         dst = skb->dst;
370
371         /* IPv6 specs say nothing about it, but it is clear that we cannot
372            send redirects to source routed frames.
373          */
374         if (skb->dev == dst->dev && dst->neighbour && opt->srcrt == 0) {
375                 struct in6_addr *target = NULL;
376                 struct rt6_info *rt;
377                 struct neighbour *n = dst->neighbour;
378
379                 /*
380                  *      incoming and outgoing devices are the same
381                  *      send a redirect.
382                  */
383
384                 rt = (struct rt6_info *) dst;
385                 if ((rt->rt6i_flags & RTF_GATEWAY))
386                         target = (struct in6_addr*)&n->primary_key;
387                 else
388                         target = &hdr->daddr;
389
390                 /* Limit redirects both by destination (here)
391                    and by source (inside ndisc_send_redirect)
392                  */
393                 if (xrlim_allow(dst, 1*HZ))
394                         ndisc_send_redirect(skb, n, target);
395         } else if (ipv6_addr_type(&hdr->saddr)&(IPV6_ADDR_MULTICAST|IPV6_ADDR_LOOPBACK
396                                                 |IPV6_ADDR_LINKLOCAL)) {
397                 /* This check is security critical. */
398                 goto error;
399         }
400
401         if (skb->len > dst_mtu(dst)) {
402                 /* Again, force OUTPUT device used as source address */
403                 skb->dev = dst->dev;
404                 icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, dst_mtu(dst), skb->dev);
405                 IP6_INC_STATS_BH(IPSTATS_MIB_INTOOBIGERRORS);
406                 IP6_INC_STATS_BH(IPSTATS_MIB_FRAGFAILS);
407                 kfree_skb(skb);
408                 return -EMSGSIZE;
409         }
410
411         if (skb_cow(skb, dst->dev->hard_header_len)) {
412                 IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
413                 goto drop;
414         }
415
416         hdr = skb->nh.ipv6h;
417
418         /* Mangling hops number delayed to point after skb COW */
419  
420         hdr->hop_limit--;
421
422         IP6_INC_STATS_BH(IPSTATS_MIB_OUTFORWDATAGRAMS);
423         return NF_HOOK(PF_INET6,NF_IP6_FORWARD, skb, skb->dev, dst->dev, ip6_forward_finish);
424
425 error:
426         IP6_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS);
427 drop:
428         kfree_skb(skb);
429         return -EINVAL;
430 }
431
432 static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
433 {
434         to->pkt_type = from->pkt_type;
435         to->priority = from->priority;
436         to->protocol = from->protocol;
437         dst_release(to->dst);
438         to->dst = dst_clone(from->dst);
439         to->dev = from->dev;
440
441 #ifdef CONFIG_NET_SCHED
442         to->tc_index = from->tc_index;
443 #endif
444 #ifdef CONFIG_NETFILTER
445         to->nfmark = from->nfmark;
446         /* Connection association is same as pre-frag packet */
447         nf_conntrack_put(to->nfct);
448         to->nfct = from->nfct;
449         nf_conntrack_get(to->nfct);
450         to->nfctinfo = from->nfctinfo;
451 #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
452         nf_conntrack_put_reasm(to->nfct_reasm);
453         to->nfct_reasm = from->nfct_reasm;
454         nf_conntrack_get_reasm(to->nfct_reasm);
455 #endif
456 #ifdef CONFIG_BRIDGE_NETFILTER
457         nf_bridge_put(to->nf_bridge);
458         to->nf_bridge = from->nf_bridge;
459         nf_bridge_get(to->nf_bridge);
460 #endif
461 #endif
462         skb_copy_secmark(to, from);
463 }
464
465 int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
466 {
467         u16 offset = sizeof(struct ipv6hdr);
468         struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.ipv6h + 1);
469         unsigned int packet_len = skb->tail - skb->nh.raw;
470         int found_rhdr = 0;
471         *nexthdr = &skb->nh.ipv6h->nexthdr;
472
473         while (offset + 1 <= packet_len) {
474
475                 switch (**nexthdr) {
476
477                 case NEXTHDR_HOP:
478                 case NEXTHDR_ROUTING:
479                 case NEXTHDR_DEST:
480                         if (**nexthdr == NEXTHDR_ROUTING) found_rhdr = 1;
481                         if (**nexthdr == NEXTHDR_DEST && found_rhdr) return offset;
482                         offset += ipv6_optlen(exthdr);
483                         *nexthdr = &exthdr->nexthdr;
484                         exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
485                         break;
486                 default :
487                         return offset;
488                 }
489         }
490
491         return offset;
492 }
493 EXPORT_SYMBOL_GPL(ip6_find_1stfragopt);
494
495 static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
496 {
497         struct net_device *dev;
498         struct sk_buff *frag;
499         struct rt6_info *rt = (struct rt6_info*)skb->dst;
500         struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
501         struct ipv6hdr *tmp_hdr;
502         struct frag_hdr *fh;
503         unsigned int mtu, hlen, left, len;
504         u32 frag_id = 0;
505         int ptr, offset = 0, err=0;
506         u8 *prevhdr, nexthdr = 0;
507
508         dev = rt->u.dst.dev;
509         hlen = ip6_find_1stfragopt(skb, &prevhdr);
510         nexthdr = *prevhdr;
511
512         mtu = dst_mtu(&rt->u.dst);
513         if (np && np->frag_size < mtu) {
514                 if (np->frag_size)
515                         mtu = np->frag_size;
516         }
517         mtu -= hlen + sizeof(struct frag_hdr);
518
519         if (skb_shinfo(skb)->frag_list) {
520                 int first_len = skb_pagelen(skb);
521
522                 if (first_len - hlen > mtu ||
523                     ((first_len - hlen) & 7) ||
524                     skb_cloned(skb))
525                         goto slow_path;
526
527                 for (frag = skb_shinfo(skb)->frag_list; frag; frag = frag->next) {
528                         /* Correct geometry. */
529                         if (frag->len > mtu ||
530                             ((frag->len & 7) && frag->next) ||
531                             skb_headroom(frag) < hlen)
532                             goto slow_path;
533
534                         /* Partially cloned skb? */
535                         if (skb_shared(frag))
536                                 goto slow_path;
537
538                         BUG_ON(frag->sk);
539                         if (skb->sk) {
540                                 sock_hold(skb->sk);
541                                 frag->sk = skb->sk;
542                                 frag->destructor = sock_wfree;
543                                 skb->truesize -= frag->truesize;
544                         }
545                 }
546
547                 err = 0;
548                 offset = 0;
549                 frag = skb_shinfo(skb)->frag_list;
550                 skb_shinfo(skb)->frag_list = NULL;
551                 /* BUILD HEADER */
552
553                 tmp_hdr = kmalloc(hlen, GFP_ATOMIC);
554                 if (!tmp_hdr) {
555                         IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
556                         return -ENOMEM;
557                 }
558
559                 *prevhdr = NEXTHDR_FRAGMENT;
560                 memcpy(tmp_hdr, skb->nh.raw, hlen);
561                 __skb_pull(skb, hlen);
562                 fh = (struct frag_hdr*)__skb_push(skb, sizeof(struct frag_hdr));
563                 skb->nh.raw = __skb_push(skb, hlen);
564                 memcpy(skb->nh.raw, tmp_hdr, hlen);
565
566                 ipv6_select_ident(skb, fh);
567                 fh->nexthdr = nexthdr;
568                 fh->reserved = 0;
569                 fh->frag_off = htons(IP6_MF);
570                 frag_id = fh->identification;
571
572                 first_len = skb_pagelen(skb);
573                 skb->data_len = first_len - skb_headlen(skb);
574                 skb->len = first_len;
575                 skb->nh.ipv6h->payload_len = htons(first_len - sizeof(struct ipv6hdr));
576  
577
578                 for (;;) {
579                         /* Prepare header of the next frame,
580                          * before previous one went down. */
581                         if (frag) {
582                                 frag->ip_summed = CHECKSUM_NONE;
583                                 frag->h.raw = frag->data;
584                                 fh = (struct frag_hdr*)__skb_push(frag, sizeof(struct frag_hdr));
585                                 frag->nh.raw = __skb_push(frag, hlen);
586                                 memcpy(frag->nh.raw, tmp_hdr, hlen);
587                                 offset += skb->len - hlen - sizeof(struct frag_hdr);
588                                 fh->nexthdr = nexthdr;
589                                 fh->reserved = 0;
590                                 fh->frag_off = htons(offset);
591                                 if (frag->next != NULL)
592                                         fh->frag_off |= htons(IP6_MF);
593                                 fh->identification = frag_id;
594                                 frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr));
595                                 ip6_copy_metadata(frag, skb);
596                         }
597                         
598                         err = output(skb);
599                         if(!err)
600                                 IP6_INC_STATS(IPSTATS_MIB_FRAGCREATES);
601
602                         if (err || !frag)
603                                 break;
604
605                         skb = frag;
606                         frag = skb->next;
607                         skb->next = NULL;
608                 }
609
610                 kfree(tmp_hdr);
611
612                 if (err == 0) {
613                         IP6_INC_STATS(IPSTATS_MIB_FRAGOKS);
614                         return 0;
615                 }
616
617                 while (frag) {
618                         skb = frag->next;
619                         kfree_skb(frag);
620                         frag = skb;
621                 }
622
623                 IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
624                 return err;
625         }
626
627 slow_path:
628         left = skb->len - hlen;         /* Space per frame */
629         ptr = hlen;                     /* Where to start from */
630
631         /*
632          *      Fragment the datagram.
633          */
634
635         *prevhdr = NEXTHDR_FRAGMENT;
636
637         /*
638          *      Keep copying data until we run out.
639          */
640         while(left > 0) {
641                 len = left;
642                 /* IF: it doesn't fit, use 'mtu' - the data space left */
643                 if (len > mtu)
644                         len = mtu;
645                 /* IF: we are not sending upto and including the packet end
646                    then align the next start on an eight byte boundary */
647                 if (len < left) {
648                         len &= ~7;
649                 }
650                 /*
651                  *      Allocate buffer.
652                  */
653
654                 if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_RESERVED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) {
655                         NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n");
656                         IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
657                         err = -ENOMEM;
658                         goto fail;
659                 }
660
661                 /*
662                  *      Set up data on packet
663                  */
664
665                 ip6_copy_metadata(frag, skb);
666                 skb_reserve(frag, LL_RESERVED_SPACE(rt->u.dst.dev));
667                 skb_put(frag, len + hlen + sizeof(struct frag_hdr));
668                 frag->nh.raw = frag->data;
669                 fh = (struct frag_hdr*)(frag->data + hlen);
670                 frag->h.raw = frag->data + hlen + sizeof(struct frag_hdr);
671
672                 /*
673                  *      Charge the memory for the fragment to any owner
674                  *      it might possess
675                  */
676                 if (skb->sk)
677                         skb_set_owner_w(frag, skb->sk);
678
679                 /*
680                  *      Copy the packet header into the new buffer.
681                  */
682                 memcpy(frag->nh.raw, skb->data, hlen);
683
684                 /*
685                  *      Build fragment header.
686                  */
687                 fh->nexthdr = nexthdr;
688                 fh->reserved = 0;
689                 if (!frag_id) {
690                         ipv6_select_ident(skb, fh);
691                         frag_id = fh->identification;
692                 } else
693                         fh->identification = frag_id;
694
695                 /*
696                  *      Copy a block of the IP datagram.
697                  */
698                 if (skb_copy_bits(skb, ptr, frag->h.raw, len))
699                         BUG();
700                 left -= len;
701
702                 fh->frag_off = htons(offset);
703                 if (left > 0)
704                         fh->frag_off |= htons(IP6_MF);
705                 frag->nh.ipv6h->payload_len = htons(frag->len - sizeof(struct ipv6hdr));
706
707                 ptr += len;
708                 offset += len;
709
710                 /*
711                  *      Put this fragment into the sending queue.
712                  */
713                 err = output(frag);
714                 if (err)
715                         goto fail;
716
717                 IP6_INC_STATS(IPSTATS_MIB_FRAGCREATES);
718         }
719         kfree_skb(skb);
720         IP6_INC_STATS(IPSTATS_MIB_FRAGOKS);
721         return err;
722
723 fail:
724         kfree_skb(skb); 
725         IP6_INC_STATS(IPSTATS_MIB_FRAGFAILS);
726         return err;
727 }
728
729 static struct dst_entry *ip6_sk_dst_check(struct sock *sk,
730                                           struct dst_entry *dst,
731                                           struct flowi *fl)
732 {
733         struct ipv6_pinfo *np = inet6_sk(sk);
734         struct rt6_info *rt = (struct rt6_info *)dst;
735
736         if (!dst)
737                 goto out;
738
739         /* Yes, checking route validity in not connected
740          * case is not very simple. Take into account,
741          * that we do not support routing by source, TOS,
742          * and MSG_DONTROUTE            --ANK (980726)
743          *
744          * 1. If route was host route, check that
745          *    cached destination is current.
746          *    If it is network route, we still may
747          *    check its validity using saved pointer
748          *    to the last used address: daddr_cache.
749          *    We do not want to save whole address now,
750          *    (because main consumer of this service
751          *    is tcp, which has not this problem),
752          *    so that the last trick works only on connected
753          *    sockets.
754          * 2. oif also should be the same.
755          */
756         if (((rt->rt6i_dst.plen != 128 ||
757               !ipv6_addr_equal(&fl->fl6_dst, &rt->rt6i_dst.addr))
758              && (np->daddr_cache == NULL ||
759                  !ipv6_addr_equal(&fl->fl6_dst, np->daddr_cache)))
760             || (fl->oif && fl->oif != dst->dev->ifindex)) {
761                 dst_release(dst);
762                 dst = NULL;
763         }
764
765 out:
766         return dst;
767 }
768
769 static int ip6_dst_lookup_tail(struct sock *sk,
770                                struct dst_entry **dst, struct flowi *fl)
771 {
772         int err;
773
774         if (*dst == NULL)
775                 *dst = ip6_route_output(sk, fl);
776
777         if ((err = (*dst)->error))
778                 goto out_err_release;
779
780         if (ipv6_addr_any(&fl->fl6_src)) {
781                 err = ipv6_get_saddr(*dst, &fl->fl6_dst, &fl->fl6_src);
782                 if (err)
783                         goto out_err_release;
784         }
785
786         return 0;
787
788 out_err_release:
789         dst_release(*dst);
790         *dst = NULL;
791         return err;
792 }
793
794 /**
795  *      ip6_dst_lookup - perform route lookup on flow
796  *      @sk: socket which provides route info
797  *      @dst: pointer to dst_entry * for result
798  *      @fl: flow to lookup
799  *
800  *      This function performs a route lookup on the given flow.
801  *
802  *      It returns zero on success, or a standard errno code on error.
803  */
804 int ip6_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
805 {
806         *dst = NULL;
807         return ip6_dst_lookup_tail(sk, dst, fl);
808 }
809 EXPORT_SYMBOL_GPL(ip6_dst_lookup);
810
811 /**
812  *      ip6_sk_dst_lookup - perform socket cached route lookup on flow
813  *      @sk: socket which provides the dst cache and route info
814  *      @dst: pointer to dst_entry * for result
815  *      @fl: flow to lookup
816  *
817  *      This function performs a route lookup on the given flow with the
818  *      possibility of using the cached route in the socket if it is valid.
819  *      It will take the socket dst lock when operating on the dst cache.
820  *      As a result, this function can only be used in process context.
821  *
822  *      It returns zero on success, or a standard errno code on error.
823  */
824 int ip6_sk_dst_lookup(struct sock *sk, struct dst_entry **dst, struct flowi *fl)
825 {
826         *dst = NULL;
827         if (sk) {
828                 *dst = sk_dst_check(sk, inet6_sk(sk)->dst_cookie);
829                 *dst = ip6_sk_dst_check(sk, *dst, fl);
830         }
831
832         return ip6_dst_lookup_tail(sk, dst, fl);
833 }
834 EXPORT_SYMBOL_GPL(ip6_sk_dst_lookup);
835
836 static inline int ip6_ufo_append_data(struct sock *sk,
837                         int getfrag(void *from, char *to, int offset, int len,
838                         int odd, struct sk_buff *skb),
839                         void *from, int length, int hh_len, int fragheaderlen,
840                         int transhdrlen, int mtu,unsigned int flags)
841
842 {
843         struct sk_buff *skb;
844         int err;
845
846         /* There is support for UDP large send offload by network
847          * device, so create one single skb packet containing complete
848          * udp datagram
849          */
850         if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) {
851                 skb = sock_alloc_send_skb(sk,
852                         hh_len + fragheaderlen + transhdrlen + 20,
853                         (flags & MSG_DONTWAIT), &err);
854                 if (skb == NULL)
855                         return -ENOMEM;
856
857                 /* reserve space for Hardware header */
858                 skb_reserve(skb, hh_len);
859
860                 /* create space for UDP/IP header */
861                 skb_put(skb,fragheaderlen + transhdrlen);
862
863                 /* initialize network header pointer */
864                 skb->nh.raw = skb->data;
865
866                 /* initialize protocol header pointer */
867                 skb->h.raw = skb->data + fragheaderlen;
868
869                 skb->ip_summed = CHECKSUM_PARTIAL;
870                 skb->csum = 0;
871                 sk->sk_sndmsg_off = 0;
872         }
873
874         err = skb_append_datato_frags(sk,skb, getfrag, from,
875                                       (length - transhdrlen));
876         if (!err) {
877                 struct frag_hdr fhdr;
878
879                 /* specify the length of each IP datagram fragment*/
880                 skb_shinfo(skb)->gso_size = mtu - fragheaderlen - 
881                                             sizeof(struct frag_hdr);
882                 skb_shinfo(skb)->gso_type = SKB_GSO_UDP;
883                 ipv6_select_ident(skb, &fhdr);
884                 skb_shinfo(skb)->ip6_frag_id = fhdr.identification;
885                 __skb_queue_tail(&sk->sk_write_queue, skb);
886
887                 return 0;
888         }
889         /* There is not enough support do UPD LSO,
890          * so follow normal path
891          */
892         kfree_skb(skb);
893
894         return err;
895 }
896
897 int ip6_append_data(struct sock *sk, int getfrag(void *from, char *to,
898         int offset, int len, int odd, struct sk_buff *skb),
899         void *from, int length, int transhdrlen,
900         int hlimit, int tclass, struct ipv6_txoptions *opt, struct flowi *fl,
901         struct rt6_info *rt, unsigned int flags)
902 {
903         struct inet_sock *inet = inet_sk(sk);
904         struct ipv6_pinfo *np = inet6_sk(sk);
905         struct sk_buff *skb;
906         unsigned int maxfraglen, fragheaderlen;
907         int exthdrlen;
908         int hh_len;
909         int mtu;
910         int copy;
911         int err;
912         int offset = 0;
913         int csummode = CHECKSUM_NONE;
914
915         if (flags&MSG_PROBE)
916                 return 0;
917         if (skb_queue_empty(&sk->sk_write_queue)) {
918                 /*
919                  * setup for corking
920                  */
921                 if (opt) {
922                         if (np->cork.opt == NULL) {
923                                 np->cork.opt = kmalloc(opt->tot_len,
924                                                        sk->sk_allocation);
925                                 if (unlikely(np->cork.opt == NULL))
926                                         return -ENOBUFS;
927                         } else if (np->cork.opt->tot_len < opt->tot_len) {
928                                 printk(KERN_DEBUG "ip6_append_data: invalid option length\n");
929                                 return -EINVAL;
930                         }
931                         memcpy(np->cork.opt, opt, opt->tot_len);
932                         inet->cork.flags |= IPCORK_OPT;
933                         /* need source address above miyazawa*/
934                 }
935                 dst_hold(&rt->u.dst);
936                 np->cork.rt = rt;
937                 inet->cork.fl = *fl;
938                 np->cork.hop_limit = hlimit;
939                 np->cork.tclass = tclass;
940                 mtu = dst_mtu(rt->u.dst.path);
941                 if (np->frag_size < mtu) {
942                         if (np->frag_size)
943                                 mtu = np->frag_size;
944                 }
945                 inet->cork.fragsize = mtu;
946                 if (dst_allfrag(rt->u.dst.path))
947                         inet->cork.flags |= IPCORK_ALLFRAG;
948                 inet->cork.length = 0;
949                 sk->sk_sndmsg_page = NULL;
950                 sk->sk_sndmsg_off = 0;
951                 exthdrlen = rt->u.dst.header_len + (opt ? opt->opt_flen : 0);
952                 length += exthdrlen;
953                 transhdrlen += exthdrlen;
954         } else {
955                 rt = np->cork.rt;
956                 fl = &inet->cork.fl;
957                 if (inet->cork.flags & IPCORK_OPT)
958                         opt = np->cork.opt;
959                 transhdrlen = 0;
960                 exthdrlen = 0;
961                 mtu = inet->cork.fragsize;
962         }
963
964         hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
965
966         fragheaderlen = sizeof(struct ipv6hdr) + (opt ? opt->opt_nflen : 0);
967         maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen - sizeof(struct frag_hdr);
968
969         if (mtu <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN) {
970                 if (inet->cork.length + length > sizeof(struct ipv6hdr) + IPV6_MAXPLEN - fragheaderlen) {
971                         ipv6_local_error(sk, EMSGSIZE, fl, mtu-exthdrlen);
972                         return -EMSGSIZE;
973                 }
974         }
975
976         /*
977          * Let's try using as much space as possible.
978          * Use MTU if total length of the message fits into the MTU.
979          * Otherwise, we need to reserve fragment header and
980          * fragment alignment (= 8-15 octects, in total).
981          *
982          * Note that we may need to "move" the data from the tail of
983          * of the buffer to the new fragment when we split 
984          * the message.
985          *
986          * FIXME: It may be fragmented into multiple chunks 
987          *        at once if non-fragmentable extension headers
988          *        are too large.
989          * --yoshfuji 
990          */
991
992         inet->cork.length += length;
993         if (((length > mtu) && (sk->sk_protocol == IPPROTO_UDP)) &&
994             (rt->u.dst.dev->features & NETIF_F_UFO)) {
995
996                 err = ip6_ufo_append_data(sk, getfrag, from, length, hh_len,
997                                           fragheaderlen, transhdrlen, mtu,
998                                           flags);
999                 if (err)
1000                         goto error;
1001                 return 0;
1002         }
1003
1004         if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL)
1005                 goto alloc_new_skb;
1006
1007         while (length > 0) {
1008                 /* Check if the remaining data fits into current packet. */
1009                 copy = (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - skb->len;
1010                 if (copy < length)
1011                         copy = maxfraglen - skb->len;
1012
1013                 if (copy <= 0) {
1014                         char *data;
1015                         unsigned int datalen;
1016                         unsigned int fraglen;
1017                         unsigned int fraggap;
1018                         unsigned int alloclen;
1019                         struct sk_buff *skb_prev;
1020 alloc_new_skb:
1021                         skb_prev = skb;
1022
1023                         /* There's no room in the current skb */
1024                         if (skb_prev)
1025                                 fraggap = skb_prev->len - maxfraglen;
1026                         else
1027                                 fraggap = 0;
1028
1029                         /*
1030                          * If remaining data exceeds the mtu,
1031                          * we know we need more fragment(s).
1032                          */
1033                         datalen = length + fraggap;
1034                         if (datalen > (inet->cork.length <= mtu && !(inet->cork.flags & IPCORK_ALLFRAG) ? mtu : maxfraglen) - fragheaderlen)
1035                                 datalen = maxfraglen - fragheaderlen;
1036
1037                         fraglen = datalen + fragheaderlen;
1038                         if ((flags & MSG_MORE) &&
1039                             !(rt->u.dst.dev->features&NETIF_F_SG))
1040                                 alloclen = mtu;
1041                         else
1042                                 alloclen = datalen + fragheaderlen;
1043
1044                         /*
1045                          * The last fragment gets additional space at tail.
1046                          * Note: we overallocate on fragments with MSG_MODE
1047                          * because we have no idea if we're the last one.
1048                          */
1049                         if (datalen == length + fraggap)
1050                                 alloclen += rt->u.dst.trailer_len;
1051
1052                         /*
1053                          * We just reserve space for fragment header.
1054                          * Note: this may be overallocation if the message 
1055                          * (without MSG_MORE) fits into the MTU.
1056                          */
1057                         alloclen += sizeof(struct frag_hdr);
1058
1059                         if (transhdrlen) {
1060                                 skb = sock_alloc_send_skb(sk,
1061                                                 alloclen + hh_len,
1062                                                 (flags & MSG_DONTWAIT), &err);
1063                         } else {
1064                                 skb = NULL;
1065                                 if (atomic_read(&sk->sk_wmem_alloc) <=
1066                                     2 * sk->sk_sndbuf)
1067                                         skb = sock_wmalloc(sk,
1068                                                            alloclen + hh_len, 1,
1069                                                            sk->sk_allocation);
1070                                 if (unlikely(skb == NULL))
1071                                         err = -ENOBUFS;
1072                         }
1073                         if (skb == NULL)
1074                                 goto error;
1075                         /*
1076                          *      Fill in the control structures
1077                          */
1078                         skb->ip_summed = csummode;
1079                         skb->csum = 0;
1080                         /* reserve for fragmentation */
1081                         skb_reserve(skb, hh_len+sizeof(struct frag_hdr));
1082
1083                         /*
1084                          *      Find where to start putting bytes
1085                          */
1086                         data = skb_put(skb, fraglen);
1087                         skb->nh.raw = data + exthdrlen;
1088                         data += fragheaderlen;
1089                         skb->h.raw = data + exthdrlen;
1090
1091                         if (fraggap) {
1092                                 skb->csum = skb_copy_and_csum_bits(
1093                                         skb_prev, maxfraglen,
1094                                         data + transhdrlen, fraggap, 0);
1095                                 skb_prev->csum = csum_sub(skb_prev->csum,
1096                                                           skb->csum);
1097                                 data += fraggap;
1098                                 pskb_trim_unique(skb_prev, maxfraglen);
1099                         }
1100                         copy = datalen - transhdrlen - fraggap;
1101                         if (copy < 0) {
1102                                 err = -EINVAL;
1103                                 kfree_skb(skb);
1104                                 goto error;
1105                         } else if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) {
1106                                 err = -EFAULT;
1107                                 kfree_skb(skb);
1108                                 goto error;
1109                         }
1110
1111                         offset += copy;
1112                         length -= datalen - fraggap;
1113                         transhdrlen = 0;
1114                         exthdrlen = 0;
1115                         csummode = CHECKSUM_NONE;
1116
1117                         /*
1118                          * Put the packet on the pending queue
1119                          */
1120                         __skb_queue_tail(&sk->sk_write_queue, skb);
1121                         continue;
1122                 }
1123
1124                 if (copy > length)
1125                         copy = length;
1126
1127                 if (!(rt->u.dst.dev->features&NETIF_F_SG)) {
1128                         unsigned int off;
1129
1130                         off = skb->len;
1131                         if (getfrag(from, skb_put(skb, copy),
1132                                                 offset, copy, off, skb) < 0) {
1133                                 __skb_trim(skb, off);
1134                                 err = -EFAULT;
1135                                 goto error;
1136                         }
1137                 } else {
1138                         int i = skb_shinfo(skb)->nr_frags;
1139                         skb_frag_t *frag = &skb_shinfo(skb)->frags[i-1];
1140                         struct page *page = sk->sk_sndmsg_page;
1141                         int off = sk->sk_sndmsg_off;
1142                         unsigned int left;
1143
1144                         if (page && (left = PAGE_SIZE - off) > 0) {
1145                                 if (copy >= left)
1146                                         copy = left;
1147                                 if (page != frag->page) {
1148                                         if (i == MAX_SKB_FRAGS) {
1149                                                 err = -EMSGSIZE;
1150                                                 goto error;
1151                                         }
1152                                         get_page(page);
1153                                         skb_fill_page_desc(skb, i, page, sk->sk_sndmsg_off, 0);
1154                                         frag = &skb_shinfo(skb)->frags[i];
1155                                 }
1156                         } else if(i < MAX_SKB_FRAGS) {
1157                                 if (copy > PAGE_SIZE)
1158                                         copy = PAGE_SIZE;
1159                                 page = alloc_pages(sk->sk_allocation, 0);
1160                                 if (page == NULL) {
1161                                         err = -ENOMEM;
1162                                         goto error;
1163                                 }
1164                                 sk->sk_sndmsg_page = page;
1165                                 sk->sk_sndmsg_off = 0;
1166
1167                                 skb_fill_page_desc(skb, i, page, 0, 0);
1168                                 frag = &skb_shinfo(skb)->frags[i];
1169                                 skb->truesize += PAGE_SIZE;
1170                                 atomic_add(PAGE_SIZE, &sk->sk_wmem_alloc);
1171                         } else {
1172                                 err = -EMSGSIZE;
1173                                 goto error;
1174                         }
1175                         if (getfrag(from, page_address(frag->page)+frag->page_offset+frag->size, offset, copy, skb->len, skb) < 0) {
1176                                 err = -EFAULT;
1177                                 goto error;
1178                         }
1179                         sk->sk_sndmsg_off += copy;
1180                         frag->size += copy;
1181                         skb->len += copy;
1182                         skb->data_len += copy;
1183                 }
1184                 offset += copy;
1185                 length -= copy;
1186         }
1187         return 0;
1188 error:
1189         inet->cork.length -= length;
1190         IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
1191         return err;
1192 }
1193
1194 int ip6_push_pending_frames(struct sock *sk)
1195 {
1196         struct sk_buff *skb, *tmp_skb;
1197         struct sk_buff **tail_skb;
1198         struct in6_addr final_dst_buf, *final_dst = &final_dst_buf;
1199         struct inet_sock *inet = inet_sk(sk);
1200         struct ipv6_pinfo *np = inet6_sk(sk);
1201         struct ipv6hdr *hdr;
1202         struct ipv6_txoptions *opt = np->cork.opt;
1203         struct rt6_info *rt = np->cork.rt;
1204         struct flowi *fl = &inet->cork.fl;
1205         unsigned char proto = fl->proto;
1206         int err = 0;
1207
1208         if ((skb = __skb_dequeue(&sk->sk_write_queue)) == NULL)
1209                 goto out;
1210         tail_skb = &(skb_shinfo(skb)->frag_list);
1211
1212         /* move skb->data to ip header from ext header */
1213         if (skb->data < skb->nh.raw)
1214                 __skb_pull(skb, skb->nh.raw - skb->data);
1215         while ((tmp_skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) {
1216                 __skb_pull(tmp_skb, skb->h.raw - skb->nh.raw);
1217                 *tail_skb = tmp_skb;
1218                 tail_skb = &(tmp_skb->next);
1219                 skb->len += tmp_skb->len;
1220                 skb->data_len += tmp_skb->len;
1221                 skb->truesize += tmp_skb->truesize;
1222                 __sock_put(tmp_skb->sk);
1223                 tmp_skb->destructor = NULL;
1224                 tmp_skb->sk = NULL;
1225         }
1226
1227         ipv6_addr_copy(final_dst, &fl->fl6_dst);
1228         __skb_pull(skb, skb->h.raw - skb->nh.raw);
1229         if (opt && opt->opt_flen)
1230                 ipv6_push_frag_opts(skb, opt, &proto);
1231         if (opt && opt->opt_nflen)
1232                 ipv6_push_nfrag_opts(skb, opt, &proto, &final_dst);
1233
1234         skb->nh.ipv6h = hdr = (struct ipv6hdr*) skb_push(skb, sizeof(struct ipv6hdr));
1235         
1236         *(u32*)hdr = fl->fl6_flowlabel |
1237                      htonl(0x60000000 | ((int)np->cork.tclass << 20));
1238
1239         if (skb->len <= sizeof(struct ipv6hdr) + IPV6_MAXPLEN)
1240                 hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
1241         else
1242                 hdr->payload_len = 0;
1243         hdr->hop_limit = np->cork.hop_limit;
1244         hdr->nexthdr = proto;
1245         ipv6_addr_copy(&hdr->saddr, &fl->fl6_src);
1246         ipv6_addr_copy(&hdr->daddr, final_dst);
1247
1248         skb->priority = sk->sk_priority;
1249
1250         skb->dst = dst_clone(&rt->u.dst);
1251         IP6_INC_STATS(IPSTATS_MIB_OUTREQUESTS); 
1252         err = NF_HOOK(PF_INET6, NF_IP6_LOCAL_OUT, skb, NULL, skb->dst->dev, dst_output);
1253         if (err) {
1254                 if (err > 0)
1255                         err = np->recverr ? net_xmit_errno(err) : 0;
1256                 if (err)
1257                         goto error;
1258         }
1259
1260 out:
1261         inet->cork.flags &= ~IPCORK_OPT;
1262         kfree(np->cork.opt);
1263         np->cork.opt = NULL;
1264         if (np->cork.rt) {
1265                 dst_release(&np->cork.rt->u.dst);
1266                 np->cork.rt = NULL;
1267                 inet->cork.flags &= ~IPCORK_ALLFRAG;
1268         }
1269         memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
1270         return err;
1271 error:
1272         goto out;
1273 }
1274
1275 void ip6_flush_pending_frames(struct sock *sk)
1276 {
1277         struct inet_sock *inet = inet_sk(sk);
1278         struct ipv6_pinfo *np = inet6_sk(sk);
1279         struct sk_buff *skb;
1280
1281         while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) {
1282                 IP6_INC_STATS(IPSTATS_MIB_OUTDISCARDS);
1283                 kfree_skb(skb);
1284         }
1285
1286         inet->cork.flags &= ~IPCORK_OPT;
1287
1288         kfree(np->cork.opt);
1289         np->cork.opt = NULL;
1290         if (np->cork.rt) {
1291                 dst_release(&np->cork.rt->u.dst);
1292                 np->cork.rt = NULL;
1293                 inet->cork.flags &= ~IPCORK_ALLFRAG;
1294         }
1295         memset(&inet->cork.fl, 0, sizeof(inet->cork.fl));
1296 }