[IPV6]: Lost locking when inserting a flowlabel in ipv6_fl_list
[powerpc.git] / net / ipv6 / ip6_flowlabel.c
1 /*
2  *      ip6_flowlabel.c         IPv6 flowlabel manager.
3  *
4  *      This program is free software; you can redistribute it and/or
5  *      modify it under the terms of the GNU General Public License
6  *      as published by the Free Software Foundation; either version
7  *      2 of the License, or (at your option) any later version.
8  *
9  *      Authors:        Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10  */
11
12 #include <linux/capability.h>
13 #include <linux/errno.h>
14 #include <linux/types.h>
15 #include <linux/socket.h>
16 #include <linux/net.h>
17 #include <linux/netdevice.h>
18 #include <linux/if_arp.h>
19 #include <linux/in6.h>
20 #include <linux/route.h>
21 #include <linux/proc_fs.h>
22 #include <linux/seq_file.h>
23
24 #include <net/net_namespace.h>
25 #include <net/sock.h>
26
27 #include <net/ipv6.h>
28 #include <net/ndisc.h>
29 #include <net/protocol.h>
30 #include <net/ip6_route.h>
31 #include <net/addrconf.h>
32 #include <net/rawv6.h>
33 #include <net/icmp.h>
34 #include <net/transp_v6.h>
35
36 #include <asm/uaccess.h>
37
38 #define FL_MIN_LINGER   6       /* Minimal linger. It is set to 6sec specified
39                                    in old IPv6 RFC. Well, it was reasonable value.
40                                  */
41 #define FL_MAX_LINGER   60      /* Maximal linger timeout */
42
43 /* FL hash table */
44
45 #define FL_MAX_PER_SOCK 32
46 #define FL_MAX_SIZE     4096
47 #define FL_HASH_MASK    255
48 #define FL_HASH(l)      (ntohl(l)&FL_HASH_MASK)
49
50 static atomic_t fl_size = ATOMIC_INIT(0);
51 static struct ip6_flowlabel *fl_ht[FL_HASH_MASK+1];
52
53 static void ip6_fl_gc(unsigned long dummy);
54 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0);
55
56 /* FL hash table lock: it protects only of GC */
57
58 static DEFINE_RWLOCK(ip6_fl_lock);
59
60 /* Big socket sock */
61
62 static DEFINE_RWLOCK(ip6_sk_fl_lock);
63
64
65 static __inline__ struct ip6_flowlabel * __fl_lookup(__be32 label)
66 {
67         struct ip6_flowlabel *fl;
68
69         for (fl=fl_ht[FL_HASH(label)]; fl; fl = fl->next) {
70                 if (fl->label == label)
71                         return fl;
72         }
73         return NULL;
74 }
75
76 static struct ip6_flowlabel * fl_lookup(__be32 label)
77 {
78         struct ip6_flowlabel *fl;
79
80         read_lock_bh(&ip6_fl_lock);
81         fl = __fl_lookup(label);
82         if (fl)
83                 atomic_inc(&fl->users);
84         read_unlock_bh(&ip6_fl_lock);
85         return fl;
86 }
87
88
89 static void fl_free(struct ip6_flowlabel *fl)
90 {
91         if (fl)
92                 kfree(fl->opt);
93         kfree(fl);
94 }
95
96 static void fl_release(struct ip6_flowlabel *fl)
97 {
98         write_lock_bh(&ip6_fl_lock);
99
100         fl->lastuse = jiffies;
101         if (atomic_dec_and_test(&fl->users)) {
102                 unsigned long ttd = fl->lastuse + fl->linger;
103                 if (time_after(ttd, fl->expires))
104                         fl->expires = ttd;
105                 ttd = fl->expires;
106                 if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
107                         struct ipv6_txoptions *opt = fl->opt;
108                         fl->opt = NULL;
109                         kfree(opt);
110                 }
111                 if (!timer_pending(&ip6_fl_gc_timer) ||
112                     time_after(ip6_fl_gc_timer.expires, ttd))
113                         mod_timer(&ip6_fl_gc_timer, ttd);
114         }
115
116         write_unlock_bh(&ip6_fl_lock);
117 }
118
119 static void ip6_fl_gc(unsigned long dummy)
120 {
121         int i;
122         unsigned long now = jiffies;
123         unsigned long sched = 0;
124
125         write_lock(&ip6_fl_lock);
126
127         for (i=0; i<=FL_HASH_MASK; i++) {
128                 struct ip6_flowlabel *fl, **flp;
129                 flp = &fl_ht[i];
130                 while ((fl=*flp) != NULL) {
131                         if (atomic_read(&fl->users) == 0) {
132                                 unsigned long ttd = fl->lastuse + fl->linger;
133                                 if (time_after(ttd, fl->expires))
134                                         fl->expires = ttd;
135                                 ttd = fl->expires;
136                                 if (time_after_eq(now, ttd)) {
137                                         *flp = fl->next;
138                                         fl_free(fl);
139                                         atomic_dec(&fl_size);
140                                         continue;
141                                 }
142                                 if (!sched || time_before(ttd, sched))
143                                         sched = ttd;
144                         }
145                         flp = &fl->next;
146                 }
147         }
148         if (!sched && atomic_read(&fl_size))
149                 sched = now + FL_MAX_LINGER;
150         if (sched) {
151                 ip6_fl_gc_timer.expires = sched;
152                 add_timer(&ip6_fl_gc_timer);
153         }
154         write_unlock(&ip6_fl_lock);
155 }
156
157 static int fl_intern(struct ip6_flowlabel *fl, __be32 label)
158 {
159         fl->label = label & IPV6_FLOWLABEL_MASK;
160
161         write_lock_bh(&ip6_fl_lock);
162         if (label == 0) {
163                 for (;;) {
164                         fl->label = htonl(net_random())&IPV6_FLOWLABEL_MASK;
165                         if (fl->label) {
166                                 struct ip6_flowlabel *lfl;
167                                 lfl = __fl_lookup(fl->label);
168                                 if (lfl == NULL)
169                                         break;
170                         }
171                 }
172         }
173
174         fl->lastuse = jiffies;
175         fl->next = fl_ht[FL_HASH(fl->label)];
176         fl_ht[FL_HASH(fl->label)] = fl;
177         atomic_inc(&fl_size);
178         write_unlock_bh(&ip6_fl_lock);
179         return 0;
180 }
181
182
183
184 /* Socket flowlabel lists */
185
186 struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, __be32 label)
187 {
188         struct ipv6_fl_socklist *sfl;
189         struct ipv6_pinfo *np = inet6_sk(sk);
190
191         label &= IPV6_FLOWLABEL_MASK;
192
193         for (sfl=np->ipv6_fl_list; sfl; sfl = sfl->next) {
194                 struct ip6_flowlabel *fl = sfl->fl;
195                 if (fl->label == label) {
196                         fl->lastuse = jiffies;
197                         atomic_inc(&fl->users);
198                         return fl;
199                 }
200         }
201         return NULL;
202 }
203
204 EXPORT_SYMBOL_GPL(fl6_sock_lookup);
205
206 void fl6_free_socklist(struct sock *sk)
207 {
208         struct ipv6_pinfo *np = inet6_sk(sk);
209         struct ipv6_fl_socklist *sfl;
210
211         while ((sfl = np->ipv6_fl_list) != NULL) {
212                 np->ipv6_fl_list = sfl->next;
213                 fl_release(sfl->fl);
214                 kfree(sfl);
215         }
216 }
217
218 /* Service routines */
219
220
221 /*
222    It is the only difficult place. flowlabel enforces equal headers
223    before and including routing header, however user may supply options
224    following rthdr.
225  */
226
227 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space,
228                                          struct ip6_flowlabel * fl,
229                                          struct ipv6_txoptions * fopt)
230 {
231         struct ipv6_txoptions * fl_opt = fl->opt;
232
233         if (fopt == NULL || fopt->opt_flen == 0)
234                 return fl_opt;
235
236         if (fl_opt != NULL) {
237                 opt_space->hopopt = fl_opt->hopopt;
238                 opt_space->dst0opt = fl_opt->dst0opt;
239                 opt_space->srcrt = fl_opt->srcrt;
240                 opt_space->opt_nflen = fl_opt->opt_nflen;
241         } else {
242                 if (fopt->opt_nflen == 0)
243                         return fopt;
244                 opt_space->hopopt = NULL;
245                 opt_space->dst0opt = NULL;
246                 opt_space->srcrt = NULL;
247                 opt_space->opt_nflen = 0;
248         }
249         opt_space->dst1opt = fopt->dst1opt;
250         opt_space->opt_flen = fopt->opt_flen;
251         return opt_space;
252 }
253
254 static unsigned long check_linger(unsigned long ttl)
255 {
256         if (ttl < FL_MIN_LINGER)
257                 return FL_MIN_LINGER*HZ;
258         if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
259                 return 0;
260         return ttl*HZ;
261 }
262
263 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
264 {
265         linger = check_linger(linger);
266         if (!linger)
267                 return -EPERM;
268         expires = check_linger(expires);
269         if (!expires)
270                 return -EPERM;
271         fl->lastuse = jiffies;
272         if (time_before(fl->linger, linger))
273                 fl->linger = linger;
274         if (time_before(expires, fl->linger))
275                 expires = fl->linger;
276         if (time_before(fl->expires, fl->lastuse + expires))
277                 fl->expires = fl->lastuse + expires;
278         return 0;
279 }
280
281 static struct ip6_flowlabel *
282 fl_create(struct in6_flowlabel_req *freq, char __user *optval, int optlen, int *err_p)
283 {
284         struct ip6_flowlabel *fl;
285         int olen;
286         int addr_type;
287         int err;
288
289         err = -ENOMEM;
290         fl = kzalloc(sizeof(*fl), GFP_KERNEL);
291         if (fl == NULL)
292                 goto done;
293
294         olen = optlen - CMSG_ALIGN(sizeof(*freq));
295         if (olen > 0) {
296                 struct msghdr msg;
297                 struct flowi flowi;
298                 int junk;
299
300                 err = -ENOMEM;
301                 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
302                 if (fl->opt == NULL)
303                         goto done;
304
305                 memset(fl->opt, 0, sizeof(*fl->opt));
306                 fl->opt->tot_len = sizeof(*fl->opt) + olen;
307                 err = -EFAULT;
308                 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
309                         goto done;
310
311                 msg.msg_controllen = olen;
312                 msg.msg_control = (void*)(fl->opt+1);
313                 flowi.oif = 0;
314
315                 err = datagram_send_ctl(&msg, &flowi, fl->opt, &junk, &junk);
316                 if (err)
317                         goto done;
318                 err = -EINVAL;
319                 if (fl->opt->opt_flen)
320                         goto done;
321                 if (fl->opt->opt_nflen == 0) {
322                         kfree(fl->opt);
323                         fl->opt = NULL;
324                 }
325         }
326
327         fl->expires = jiffies;
328         err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
329         if (err)
330                 goto done;
331         fl->share = freq->flr_share;
332         addr_type = ipv6_addr_type(&freq->flr_dst);
333         if ((addr_type&IPV6_ADDR_MAPPED)
334             || addr_type == IPV6_ADDR_ANY) {
335                 err = -EINVAL;
336                 goto done;
337         }
338         ipv6_addr_copy(&fl->dst, &freq->flr_dst);
339         atomic_set(&fl->users, 1);
340         switch (fl->share) {
341         case IPV6_FL_S_EXCL:
342         case IPV6_FL_S_ANY:
343                 break;
344         case IPV6_FL_S_PROCESS:
345                 fl->owner = current->pid;
346                 break;
347         case IPV6_FL_S_USER:
348                 fl->owner = current->euid;
349                 break;
350         default:
351                 err = -EINVAL;
352                 goto done;
353         }
354         return fl;
355
356 done:
357         fl_free(fl);
358         *err_p = err;
359         return NULL;
360 }
361
362 static int mem_check(struct sock *sk)
363 {
364         struct ipv6_pinfo *np = inet6_sk(sk);
365         struct ipv6_fl_socklist *sfl;
366         int room = FL_MAX_SIZE - atomic_read(&fl_size);
367         int count = 0;
368
369         if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
370                 return 0;
371
372         for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next)
373                 count++;
374
375         if (room <= 0 ||
376             ((count >= FL_MAX_PER_SOCK ||
377              (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4)
378              && !capable(CAP_NET_ADMIN)))
379                 return -ENOBUFS;
380
381         return 0;
382 }
383
384 static int ipv6_hdr_cmp(struct ipv6_opt_hdr *h1, struct ipv6_opt_hdr *h2)
385 {
386         if (h1 == h2)
387                 return 0;
388         if (h1 == NULL || h2 == NULL)
389                 return 1;
390         if (h1->hdrlen != h2->hdrlen)
391                 return 1;
392         return memcmp(h1+1, h2+1, ((h1->hdrlen+1)<<3) - sizeof(*h1));
393 }
394
395 static int ipv6_opt_cmp(struct ipv6_txoptions *o1, struct ipv6_txoptions *o2)
396 {
397         if (o1 == o2)
398                 return 0;
399         if (o1 == NULL || o2 == NULL)
400                 return 1;
401         if (o1->opt_nflen != o2->opt_nflen)
402                 return 1;
403         if (ipv6_hdr_cmp(o1->hopopt, o2->hopopt))
404                 return 1;
405         if (ipv6_hdr_cmp(o1->dst0opt, o2->dst0opt))
406                 return 1;
407         if (ipv6_hdr_cmp((struct ipv6_opt_hdr *)o1->srcrt, (struct ipv6_opt_hdr *)o2->srcrt))
408                 return 1;
409         return 0;
410 }
411
412 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
413                 struct ip6_flowlabel *fl)
414 {
415         write_lock_bh(&ip6_sk_fl_lock);
416         sfl->fl = fl;
417         sfl->next = np->ipv6_fl_list;
418         np->ipv6_fl_list = sfl;
419         write_unlock_bh(&ip6_sk_fl_lock);
420 }
421
422 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
423 {
424         int err;
425         struct ipv6_pinfo *np = inet6_sk(sk);
426         struct in6_flowlabel_req freq;
427         struct ipv6_fl_socklist *sfl1=NULL;
428         struct ipv6_fl_socklist *sfl, **sflp;
429         struct ip6_flowlabel *fl;
430
431         if (optlen < sizeof(freq))
432                 return -EINVAL;
433
434         if (copy_from_user(&freq, optval, sizeof(freq)))
435                 return -EFAULT;
436
437         switch (freq.flr_action) {
438         case IPV6_FL_A_PUT:
439                 write_lock_bh(&ip6_sk_fl_lock);
440                 for (sflp = &np->ipv6_fl_list; (sfl=*sflp)!=NULL; sflp = &sfl->next) {
441                         if (sfl->fl->label == freq.flr_label) {
442                                 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
443                                         np->flow_label &= ~IPV6_FLOWLABEL_MASK;
444                                 *sflp = sfl->next;
445                                 write_unlock_bh(&ip6_sk_fl_lock);
446                                 fl_release(sfl->fl);
447                                 kfree(sfl);
448                                 return 0;
449                         }
450                 }
451                 write_unlock_bh(&ip6_sk_fl_lock);
452                 return -ESRCH;
453
454         case IPV6_FL_A_RENEW:
455                 read_lock_bh(&ip6_sk_fl_lock);
456                 for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
457                         if (sfl->fl->label == freq.flr_label) {
458                                 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
459                                 read_unlock_bh(&ip6_sk_fl_lock);
460                                 return err;
461                         }
462                 }
463                 read_unlock_bh(&ip6_sk_fl_lock);
464
465                 if (freq.flr_share == IPV6_FL_S_NONE && capable(CAP_NET_ADMIN)) {
466                         fl = fl_lookup(freq.flr_label);
467                         if (fl) {
468                                 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
469                                 fl_release(fl);
470                                 return err;
471                         }
472                 }
473                 return -ESRCH;
474
475         case IPV6_FL_A_GET:
476                 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
477                         return -EINVAL;
478
479                 fl = fl_create(&freq, optval, optlen, &err);
480                 if (fl == NULL)
481                         return err;
482                 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
483
484                 if (freq.flr_label) {
485                         struct ip6_flowlabel *fl1 = NULL;
486
487                         err = -EEXIST;
488                         read_lock_bh(&ip6_sk_fl_lock);
489                         for (sfl = np->ipv6_fl_list; sfl; sfl = sfl->next) {
490                                 if (sfl->fl->label == freq.flr_label) {
491                                         if (freq.flr_flags&IPV6_FL_F_EXCL) {
492                                                 read_unlock_bh(&ip6_sk_fl_lock);
493                                                 goto done;
494                                         }
495                                         fl1 = sfl->fl;
496                                         atomic_inc(&fl1->users);
497                                         break;
498                                 }
499                         }
500                         read_unlock_bh(&ip6_sk_fl_lock);
501
502                         if (fl1 == NULL)
503                                 fl1 = fl_lookup(freq.flr_label);
504                         if (fl1) {
505                                 err = -EEXIST;
506                                 if (freq.flr_flags&IPV6_FL_F_EXCL)
507                                         goto release;
508                                 err = -EPERM;
509                                 if (fl1->share == IPV6_FL_S_EXCL ||
510                                     fl1->share != fl->share ||
511                                     fl1->owner != fl->owner)
512                                         goto release;
513
514                                 err = -EINVAL;
515                                 if (!ipv6_addr_equal(&fl1->dst, &fl->dst) ||
516                                     ipv6_opt_cmp(fl1->opt, fl->opt))
517                                         goto release;
518
519                                 err = -ENOMEM;
520                                 if (sfl1 == NULL)
521                                         goto release;
522                                 if (fl->linger > fl1->linger)
523                                         fl1->linger = fl->linger;
524                                 if ((long)(fl->expires - fl1->expires) > 0)
525                                         fl1->expires = fl->expires;
526                                 fl_link(np, sfl1, fl1);
527                                 fl_free(fl);
528                                 return 0;
529
530 release:
531                                 fl_release(fl1);
532                                 goto done;
533                         }
534                 }
535                 err = -ENOENT;
536                 if (!(freq.flr_flags&IPV6_FL_F_CREATE))
537                         goto done;
538
539                 err = -ENOMEM;
540                 if (sfl1 == NULL || (err = mem_check(sk)) != 0)
541                         goto done;
542
543                 err = fl_intern(fl, freq.flr_label);
544                 if (err)
545                         goto done;
546
547                 if (!freq.flr_label) {
548                         if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
549                                          &fl->label, sizeof(fl->label))) {
550                                 /* Intentionally ignore fault. */
551                         }
552                 }
553
554                 fl_link(np, sfl1, fl);
555                 return 0;
556
557         default:
558                 return -EINVAL;
559         }
560
561 done:
562         fl_free(fl);
563         kfree(sfl1);
564         return err;
565 }
566
567 #ifdef CONFIG_PROC_FS
568
569 struct ip6fl_iter_state {
570         int bucket;
571 };
572
573 #define ip6fl_seq_private(seq)  ((struct ip6fl_iter_state *)(seq)->private)
574
575 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
576 {
577         struct ip6_flowlabel *fl = NULL;
578         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
579
580         for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
581                 if (fl_ht[state->bucket]) {
582                         fl = fl_ht[state->bucket];
583                         break;
584                 }
585         }
586         return fl;
587 }
588
589 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
590 {
591         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
592
593         fl = fl->next;
594         while (!fl) {
595                 if (++state->bucket <= FL_HASH_MASK)
596                         fl = fl_ht[state->bucket];
597                 else
598                         break;
599         }
600         return fl;
601 }
602
603 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
604 {
605         struct ip6_flowlabel *fl = ip6fl_get_first(seq);
606         if (fl)
607                 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
608                         --pos;
609         return pos ? NULL : fl;
610 }
611
612 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
613 {
614         read_lock_bh(&ip6_fl_lock);
615         return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
616 }
617
618 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
619 {
620         struct ip6_flowlabel *fl;
621
622         if (v == SEQ_START_TOKEN)
623                 fl = ip6fl_get_first(seq);
624         else
625                 fl = ip6fl_get_next(seq, v);
626         ++*pos;
627         return fl;
628 }
629
630 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
631 {
632         read_unlock_bh(&ip6_fl_lock);
633 }
634
635 static int ip6fl_seq_show(struct seq_file *seq, void *v)
636 {
637         if (v == SEQ_START_TOKEN)
638                 seq_printf(seq, "%-5s %-1s %-6s %-6s %-6s %-8s %-32s %s\n",
639                            "Label", "S", "Owner", "Users", "Linger", "Expires", "Dst", "Opt");
640         else {
641                 struct ip6_flowlabel *fl = v;
642                 seq_printf(seq,
643                            "%05X %-1d %-6d %-6d %-6ld %-8ld " NIP6_SEQFMT " %-4d\n",
644                            (unsigned)ntohl(fl->label),
645                            fl->share,
646                            (unsigned)fl->owner,
647                            atomic_read(&fl->users),
648                            fl->linger/HZ,
649                            (long)(fl->expires - jiffies)/HZ,
650                            NIP6(fl->dst),
651                            fl->opt ? fl->opt->opt_nflen : 0);
652         }
653         return 0;
654 }
655
656 static const struct seq_operations ip6fl_seq_ops = {
657         .start  =       ip6fl_seq_start,
658         .next   =       ip6fl_seq_next,
659         .stop   =       ip6fl_seq_stop,
660         .show   =       ip6fl_seq_show,
661 };
662
663 static int ip6fl_seq_open(struct inode *inode, struct file *file)
664 {
665         return seq_open_private(file, &ip6fl_seq_ops,
666                         sizeof(struct ip6fl_iter_state));
667 }
668
669 static const struct file_operations ip6fl_seq_fops = {
670         .owner          =       THIS_MODULE,
671         .open           =       ip6fl_seq_open,
672         .read           =       seq_read,
673         .llseek         =       seq_lseek,
674         .release        =       seq_release_private,
675 };
676 #endif
677
678
679 void ip6_flowlabel_init(void)
680 {
681 #ifdef CONFIG_PROC_FS
682         proc_net_fops_create(&init_net, "ip6_flowlabel", S_IRUGO, &ip6fl_seq_fops);
683 #endif
684 }
685
686 void ip6_flowlabel_cleanup(void)
687 {
688         del_timer(&ip6_fl_gc_timer);
689 #ifdef CONFIG_PROC_FS
690         proc_net_remove(&init_net, "ip6_flowlabel");
691 #endif
692 }