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/in6.h>
  19 #include <linux/proc_fs.h>
  20 #include <linux/seq_file.h>
  21 #include <linux/slab.h>
  22 #include <linux/export.h>
  23 #include <linux/pid_namespace.h>
  24
  25 #include <net/net_namespace.h>
  26 #include <net/sock.h>
  27
  28 #include <net/ipv6.h>
  29 #include <net/addrconf.h>
  30 #include <net/rawv6.h>
  31 #include <net/transp_v6.h>
  32
  33 #include <asm/uaccess.h>
  34
  35 #define FL_MIN_LINGER   6       /* Minimal linger. It is set to 6sec specified
  36                                    in old IPv6 RFC. Well, it was reasonable value.
  37                                  */
  38 #define FL_MAX_LINGER   150     /* Maximal linger timeout */
  39
  40 /* FL hash table */
  41
  42 #define FL_MAX_PER_SOCK 32
  43 #define FL_MAX_SIZE     4096
  44 #define FL_HASH_MASK    255
  45 #define FL_HASH(l)      (ntohl(l)&FL_HASH_MASK)
  46
  47 static atomic_t fl_size = ATOMIC_INIT(0);
  48 static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1];
  49
  50 static void ip6_fl_gc(unsigned long dummy);
  51 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc, 0, 0);
  52
  53 /* FL hash table lock: it protects only of GC */
  54
  55 static DEFINE_SPINLOCK(ip6_fl_lock);
  56
  57 /* Big socket sock */
  58
  59 static DEFINE_SPINLOCK(ip6_sk_fl_lock);
  60
  61 #define for_each_fl_rcu(hash, fl)                               \
  62         for (fl = rcu_dereference_bh(fl_ht[(hash)]);            \
  63              fl != NULL;                                        \
  64              fl = rcu_dereference_bh(fl->next))
  65 #define for_each_fl_continue_rcu(fl)                            \
  66         for (fl = rcu_dereference_bh(fl->next);                 \
  67              fl != NULL;                                        \
  68              fl = rcu_dereference_bh(fl->next))
  69
  70 #define for_each_sk_fl_rcu(np, sfl)                             \
  71         for (sfl = rcu_dereference_bh(np->ipv6_fl_list);        \
  72              sfl != NULL;                                       \
  73              sfl = rcu_dereference_bh(sfl->next))
  74
  75 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label)
  76 {
  77         struct ip6_flowlabel *fl;
  78
  79         for_each_fl_rcu(FL_HASH(label), fl) {
  80                 if (fl->label == label && net_eq(fl->fl_net, net))
  81                         return fl;
  82         }
  83         return NULL;
  84 }
  85
  86 static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label)
  87 {
  88         struct ip6_flowlabel *fl;
  89
  90         rcu_read_lock_bh();
  91         fl = __fl_lookup(net, label);
  92         if (fl && !atomic_inc_not_zero(&fl->users))
  93                 fl = NULL;
  94         rcu_read_unlock_bh();
  95         return fl;
  96 }
  97
  98
  99 static void fl_free(struct ip6_flowlabel *fl)
 100 {
 101         if (fl) {
 102                 if (fl->share == IPV6_FL_S_PROCESS)
 103                         put_pid(fl->owner.pid);
 104                 release_net(fl->fl_net);
 105                 kfree(fl->opt);
 106                 kfree_rcu(fl, rcu);
 107         }
 108 }
 109
 110 static void fl_release(struct ip6_flowlabel *fl)
 111 {
 112         spin_lock_bh(&ip6_fl_lock);
 113
 114         fl->lastuse = jiffies;
 115         if (atomic_dec_and_test(&fl->users)) {
 116                 unsigned long ttd = fl->lastuse + fl->linger;
 117                 if (time_after(ttd, fl->expires))
 118                         fl->expires = ttd;
 119                 ttd = fl->expires;
 120                 if (fl->opt && fl->share == IPV6_FL_S_EXCL) {
 121                         struct ipv6_txoptions *opt = fl->opt;
 122                         fl->opt = NULL;
 123                         kfree(opt);
 124                 }
 125                 if (!timer_pending(&ip6_fl_gc_timer) ||
 126                     time_after(ip6_fl_gc_timer.expires, ttd))
 127                         mod_timer(&ip6_fl_gc_timer, ttd);
 128         }
 129         spin_unlock_bh(&ip6_fl_lock);
 130 }
 131
 132 static void ip6_fl_gc(unsigned long dummy)
 133 {
 134         int i;
 135         unsigned long now = jiffies;
 136         unsigned long sched = 0;
 137
 138         spin_lock(&ip6_fl_lock);
 139
 140         for (i=0; i<=FL_HASH_MASK; i++) {
 141                 struct ip6_flowlabel *fl;
 142                 struct ip6_flowlabel __rcu **flp;
 143
 144                 flp = &fl_ht[i];
 145                 while ((fl = rcu_dereference_protected(*flp,
 146                                                        lockdep_is_held(&ip6_fl_lock))) != NULL) {
 147                         if (atomic_read(&fl->users) == 0) {
 148                                 unsigned long ttd = fl->lastuse + fl->linger;
 149                                 if (time_after(ttd, fl->expires))
 150                                         fl->expires = ttd;
 151                                 ttd = fl->expires;
 152                                 if (time_after_eq(now, ttd)) {
 153                                         *flp = fl->next;
 154                                         fl_free(fl);
 155                                         atomic_dec(&fl_size);
 156                                         continue;
 157                                 }
 158                                 if (!sched || time_before(ttd, sched))
 159                                         sched = ttd;
 160                         }
 161                         flp = &fl->next;
 162                 }
 163         }
 164         if (!sched && atomic_read(&fl_size))
 165                 sched = now + FL_MAX_LINGER;
 166         if (sched) {
 167                 mod_timer(&ip6_fl_gc_timer, sched);
 168         }
 169         spin_unlock(&ip6_fl_lock);
 170 }
 171
 172 static void __net_exit ip6_fl_purge(struct net *net)
 173 {
 174         int i;
 175
 176         spin_lock(&ip6_fl_lock);
 177         for (i = 0; i <= FL_HASH_MASK; i++) {
 178                 struct ip6_flowlabel *fl;
 179                 struct ip6_flowlabel __rcu **flp;
 180
 181                 flp = &fl_ht[i];
 182                 while ((fl = rcu_dereference_protected(*flp,
 183                                                        lockdep_is_held(&ip6_fl_lock))) != NULL) {
 184                         if (net_eq(fl->fl_net, net) &&
 185                             atomic_read(&fl->users) == 0) {
 186                                 *flp = fl->next;
 187                                 fl_free(fl);
 188                                 atomic_dec(&fl_size);
 189                                 continue;
 190                         }
 191                         flp = &fl->next;
 192                 }
 193         }
 194         spin_unlock(&ip6_fl_lock);
 195 }
 196
 197 static struct ip6_flowlabel *fl_intern(struct net *net,
 198                                        struct ip6_flowlabel *fl, __be32 label)
 199 {
 200         struct ip6_flowlabel *lfl;
 201
 202         fl->label = label & IPV6_FLOWLABEL_MASK;
 203
 204         spin_lock_bh(&ip6_fl_lock);
 205         if (label == 0) {
 206                 for (;;) {
 207                         fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK;
 208                         if (fl->label) {
 209                                 lfl = __fl_lookup(net, fl->label);
 210                                 if (lfl == NULL)
 211                                         break;
 212                         }
 213                 }
 214         } else {
 215                 /*
 216                  * we dropper the ip6_fl_lock, so this entry could reappear
 217                  * and we need to recheck with it.
 218                  *
 219                  * OTOH no need to search the active socket first, like it is
 220                  * done in ipv6_flowlabel_opt - sock is locked, so new entry
 221                  * with the same label can only appear on another sock
 222                  */
 223                 lfl = __fl_lookup(net, fl->label);
 224                 if (lfl != NULL) {
 225                         atomic_inc(&lfl->users);
 226                         spin_unlock_bh(&ip6_fl_lock);
 227                         return lfl;
 228                 }
 229         }
 230
 231         fl->lastuse = jiffies;
 232         fl->next = fl_ht[FL_HASH(fl->label)];
 233         rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl);
 234         atomic_inc(&fl_size);
 235         spin_unlock_bh(&ip6_fl_lock);
 236         return NULL;
 237 }
 238
 239
 240
 241 /* Socket flowlabel lists */
 242
 243 struct ip6_flowlabel * fl6_sock_lookup(struct sock *sk, __be32 label)
 244 {
 245         struct ipv6_fl_socklist *sfl;
 246         struct ipv6_pinfo *np = inet6_sk(sk);
 247
 248         label &= IPV6_FLOWLABEL_MASK;
 249
 250         rcu_read_lock_bh();
 251         for_each_sk_fl_rcu(np, sfl) {
 252                 struct ip6_flowlabel *fl = sfl->fl;
 253                 if (fl->label == label) {
 254                         fl->lastuse = jiffies;
 255                         atomic_inc(&fl->users);
 256                         rcu_read_unlock_bh();
 257                         return fl;
 258                 }
 259         }
 260         rcu_read_unlock_bh();
 261         return NULL;
 262 }
 263
 264 EXPORT_SYMBOL_GPL(fl6_sock_lookup);
 265
 266 void fl6_free_socklist(struct sock *sk)
 267 {
 268         struct ipv6_pinfo *np = inet6_sk(sk);
 269         struct ipv6_fl_socklist *sfl;
 270
 271         if (!rcu_access_pointer(np->ipv6_fl_list))
 272                 return;
 273
 274         spin_lock_bh(&ip6_sk_fl_lock);
 275         while ((sfl = rcu_dereference_protected(np->ipv6_fl_list,
 276                                                 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) {
 277                 np->ipv6_fl_list = sfl->next;
 278                 spin_unlock_bh(&ip6_sk_fl_lock);
 279
 280                 fl_release(sfl->fl);
 281                 kfree_rcu(sfl, rcu);
 282
 283                 spin_lock_bh(&ip6_sk_fl_lock);
 284         }
 285         spin_unlock_bh(&ip6_sk_fl_lock);
 286 }
 287
 288 /* Service routines */
 289
 290
 291 /*
 292    It is the only difficult place. flowlabel enforces equal headers
 293    before and including routing header, however user may supply options
 294    following rthdr.
 295  */
 296
 297 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions * opt_space,
 298                                          struct ip6_flowlabel * fl,
 299                                          struct ipv6_txoptions * fopt)
 300 {
 301         struct ipv6_txoptions * fl_opt = fl->opt;
 302
 303         if (fopt == NULL || fopt->opt_flen == 0)
 304                 return fl_opt;
 305
 306         if (fl_opt != NULL) {
 307                 opt_space->hopopt = fl_opt->hopopt;
 308                 opt_space->dst0opt = fl_opt->dst0opt;
 309                 opt_space->srcrt = fl_opt->srcrt;
 310                 opt_space->opt_nflen = fl_opt->opt_nflen;
 311         } else {
 312                 if (fopt->opt_nflen == 0)
 313                         return fopt;
 314                 opt_space->hopopt = NULL;
 315                 opt_space->dst0opt = NULL;
 316                 opt_space->srcrt = NULL;
 317                 opt_space->opt_nflen = 0;
 318         }
 319         opt_space->dst1opt = fopt->dst1opt;
 320         opt_space->opt_flen = fopt->opt_flen;
 321         return opt_space;
 322 }
 323 EXPORT_SYMBOL_GPL(fl6_merge_options);
 324
 325 static unsigned long check_linger(unsigned long ttl)
 326 {
 327         if (ttl < FL_MIN_LINGER)
 328                 return FL_MIN_LINGER*HZ;
 329         if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN))
 330                 return 0;
 331         return ttl*HZ;
 332 }
 333
 334 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires)
 335 {
 336         linger = check_linger(linger);
 337         if (!linger)
 338                 return -EPERM;
 339         expires = check_linger(expires);
 340         if (!expires)
 341                 return -EPERM;
 342
 343         spin_lock_bh(&ip6_fl_lock);
 344         fl->lastuse = jiffies;
 345         if (time_before(fl->linger, linger))
 346                 fl->linger = linger;
 347         if (time_before(expires, fl->linger))
 348                 expires = fl->linger;
 349         if (time_before(fl->expires, fl->lastuse + expires))
 350                 fl->expires = fl->lastuse + expires;
 351         spin_unlock_bh(&ip6_fl_lock);
 352
 353         return 0;
 354 }
 355
 356 static struct ip6_flowlabel *
 357 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq,
 358           char __user *optval, int optlen, int *err_p)
 359 {
 360         struct ip6_flowlabel *fl = NULL;
 361         int olen;
 362         int addr_type;
 363         int err;
 364
 365         olen = optlen - CMSG_ALIGN(sizeof(*freq));
 366         err = -EINVAL;
 367         if (olen > 64 * 1024)
 368                 goto done;
 369
 370         err = -ENOMEM;
 371         fl = kzalloc(sizeof(*fl), GFP_KERNEL);
 372         if (fl == NULL)
 373                 goto done;
 374
 375         if (olen > 0) {
 376                 struct msghdr msg;
 377                 struct flowi6 flowi6;
 378                 int junk;
 379
 380                 err = -ENOMEM;
 381                 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL);
 382                 if (fl->opt == NULL)
 383                         goto done;
 384
 385                 memset(fl->opt, 0, sizeof(*fl->opt));
 386                 fl->opt->tot_len = sizeof(*fl->opt) + olen;
 387                 err = -EFAULT;
 388                 if (copy_from_user(fl->opt+1, optval+CMSG_ALIGN(sizeof(*freq)), olen))
 389                         goto done;
 390
 391                 msg.msg_controllen = olen;
 392                 msg.msg_control = (void*)(fl->opt+1);
 393                 memset(&flowi6, 0, sizeof(flowi6));
 394
 395                 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, fl->opt,
 396                                             &junk, &junk, &junk);
 397                 if (err)
 398                         goto done;
 399                 err = -EINVAL;
 400                 if (fl->opt->opt_flen)
 401                         goto done;
 402                 if (fl->opt->opt_nflen == 0) {
 403                         kfree(fl->opt);
 404                         fl->opt = NULL;
 405                 }
 406         }
 407
 408         fl->fl_net = hold_net(net);
 409         fl->expires = jiffies;
 410         err = fl6_renew(fl, freq->flr_linger, freq->flr_expires);
 411         if (err)
 412                 goto done;
 413         fl->share = freq->flr_share;
 414         addr_type = ipv6_addr_type(&freq->flr_dst);
 415         if ((addr_type & IPV6_ADDR_MAPPED) ||
 416             addr_type == IPV6_ADDR_ANY) {
 417                 err = -EINVAL;
 418                 goto done;
 419         }
 420         fl->dst = freq->flr_dst;
 421         atomic_set(&fl->users, 1);
 422         switch (fl->share) {
 423         case IPV6_FL_S_EXCL:
 424         case IPV6_FL_S_ANY:
 425                 break;
 426         case IPV6_FL_S_PROCESS:
 427                 fl->owner.pid = get_task_pid(current, PIDTYPE_PID);
 428                 break;
 429         case IPV6_FL_S_USER:
 430                 fl->owner.uid = current_euid();
 431                 break;
 432         default:
 433                 err = -EINVAL;
 434                 goto done;
 435         }
 436         return fl;
 437
 438 done:
 439         fl_free(fl);
 440         *err_p = err;
 441         return NULL;
 442 }
 443
 444 static int mem_check(struct sock *sk)
 445 {
 446         struct ipv6_pinfo *np = inet6_sk(sk);
 447         struct ipv6_fl_socklist *sfl;
 448         int room = FL_MAX_SIZE - atomic_read(&fl_size);
 449         int count = 0;
 450
 451         if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK)
 452                 return 0;
 453
 454         rcu_read_lock_bh();
 455         for_each_sk_fl_rcu(np, sfl)
 456                 count++;
 457         rcu_read_unlock_bh();
 458
 459         if (room <= 0 ||
 460             ((count >= FL_MAX_PER_SOCK ||
 461               (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) &&
 462              !capable(CAP_NET_ADMIN)))
 463                 return -ENOBUFS;
 464
 465         return 0;
 466 }
 467
 468 static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl,
 469                 struct ip6_flowlabel *fl)
 470 {
 471         spin_lock_bh(&ip6_sk_fl_lock);
 472         sfl->fl = fl;
 473         sfl->next = np->ipv6_fl_list;
 474         rcu_assign_pointer(np->ipv6_fl_list, sfl);
 475         spin_unlock_bh(&ip6_sk_fl_lock);
 476 }
 477
 478 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq,
 479                            int flags)
 480 {
 481         struct ipv6_pinfo *np = inet6_sk(sk);
 482         struct ipv6_fl_socklist *sfl;
 483
 484         if (flags & IPV6_FL_F_REMOTE) {
 485                 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK;
 486                 return 0;
 487         }
 488
 489         if (np->repflow) {
 490                 freq->flr_label = np->flow_label;
 491                 return 0;
 492         }
 493
 494         rcu_read_lock_bh();
 495
 496         for_each_sk_fl_rcu(np, sfl) {
 497                 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) {
 498                         spin_lock_bh(&ip6_fl_lock);
 499                         freq->flr_label = sfl->fl->label;
 500                         freq->flr_dst = sfl->fl->dst;
 501                         freq->flr_share = sfl->fl->share;
 502                         freq->flr_expires = (sfl->fl->expires - jiffies) / HZ;
 503                         freq->flr_linger = sfl->fl->linger / HZ;
 504
 505                         spin_unlock_bh(&ip6_fl_lock);
 506                         rcu_read_unlock_bh();
 507                         return 0;
 508                 }
 509         }
 510         rcu_read_unlock_bh();
 511
 512         return -ENOENT;
 513 }
 514
 515 int ipv6_flowlabel_opt(struct sock *sk, char __user *optval, int optlen)
 516 {
 517         int uninitialized_var(err);
 518         struct net *net = sock_net(sk);
 519         struct ipv6_pinfo *np = inet6_sk(sk);
 520         struct in6_flowlabel_req freq;
 521         struct ipv6_fl_socklist *sfl1=NULL;
 522         struct ipv6_fl_socklist *sfl;
 523         struct ipv6_fl_socklist __rcu **sflp;
 524         struct ip6_flowlabel *fl, *fl1 = NULL;
 525
 526
 527         if (optlen < sizeof(freq))
 528                 return -EINVAL;
 529
 530         if (copy_from_user(&freq, optval, sizeof(freq)))
 531                 return -EFAULT;
 532
 533         switch (freq.flr_action) {
 534         case IPV6_FL_A_PUT:
 535                 if (freq.flr_flags & IPV6_FL_F_REFLECT) {
 536                         if (sk->sk_protocol != IPPROTO_TCP)
 537                                 return -ENOPROTOOPT;
 538                         if (!np->repflow)
 539                                 return -ESRCH;
 540                         np->flow_label = 0;
 541                         np->repflow = 0;
 542                         return 0;
 543                 }
 544                 spin_lock_bh(&ip6_sk_fl_lock);
 545                 for (sflp = &np->ipv6_fl_list;
 546                      (sfl = rcu_dereference(*sflp))!=NULL;
 547                      sflp = &sfl->next) {
 548                         if (sfl->fl->label == freq.flr_label) {
 549                                 if (freq.flr_label == (np->flow_label&IPV6_FLOWLABEL_MASK))
 550                                         np->flow_label &= ~IPV6_FLOWLABEL_MASK;
 551                                 *sflp = rcu_dereference(sfl->next);
 552                                 spin_unlock_bh(&ip6_sk_fl_lock);
 553                                 fl_release(sfl->fl);
 554                                 kfree_rcu(sfl, rcu);
 555                                 return 0;
 556                         }
 557                 }
 558                 spin_unlock_bh(&ip6_sk_fl_lock);
 559                 return -ESRCH;
 560
 561         case IPV6_FL_A_RENEW:
 562                 rcu_read_lock_bh();
 563                 for_each_sk_fl_rcu(np, sfl) {
 564                         if (sfl->fl->label == freq.flr_label) {
 565                                 err = fl6_renew(sfl->fl, freq.flr_linger, freq.flr_expires);
 566                                 rcu_read_unlock_bh();
 567                                 return err;
 568                         }
 569                 }
 570                 rcu_read_unlock_bh();
 571
 572                 if (freq.flr_share == IPV6_FL_S_NONE &&
 573                     ns_capable(net->user_ns, CAP_NET_ADMIN)) {
 574                         fl = fl_lookup(net, freq.flr_label);
 575                         if (fl) {
 576                                 err = fl6_renew(fl, freq.flr_linger, freq.flr_expires);
 577                                 fl_release(fl);
 578                                 return err;
 579                         }
 580                 }
 581                 return -ESRCH;
 582
 583         case IPV6_FL_A_GET:
 584                 if (freq.flr_flags & IPV6_FL_F_REFLECT) {
 585                         struct net *net = sock_net(sk);
 586                         if (net->ipv6.sysctl.flowlabel_consistency) {
 587                                 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n");
 588                                 return -EPERM;
 589                         }
 590
 591                         if (sk->sk_protocol != IPPROTO_TCP)
 592                                 return -ENOPROTOOPT;
 593
 594                         np->repflow = 1;
 595                         return 0;
 596                 }
 597
 598                 if (freq.flr_label & ~IPV6_FLOWLABEL_MASK)
 599                         return -EINVAL;
 600
 601                 fl = fl_create(net, sk, &freq, optval, optlen, &err);
 602                 if (fl == NULL)
 603                         return err;
 604                 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL);
 605
 606                 if (freq.flr_label) {
 607                         err = -EEXIST;
 608                         rcu_read_lock_bh();
 609                         for_each_sk_fl_rcu(np, sfl) {
 610                                 if (sfl->fl->label == freq.flr_label) {
 611                                         if (freq.flr_flags&IPV6_FL_F_EXCL) {
 612                                                 rcu_read_unlock_bh();
 613                                                 goto done;
 614                                         }
 615                                         fl1 = sfl->fl;
 616                                         atomic_inc(&fl1->users);
 617                                         break;
 618                                 }
 619                         }
 620                         rcu_read_unlock_bh();
 621
 622                         if (fl1 == NULL)
 623                                 fl1 = fl_lookup(net, freq.flr_label);
 624                         if (fl1) {
 625 recheck:
 626                                 err = -EEXIST;
 627                                 if (freq.flr_flags&IPV6_FL_F_EXCL)
 628                                         goto release;
 629                                 err = -EPERM;
 630                                 if (fl1->share == IPV6_FL_S_EXCL ||
 631                                     fl1->share != fl->share ||
 632                                     ((fl1->share == IPV6_FL_S_PROCESS) &&
 633                                      (fl1->owner.pid == fl->owner.pid)) ||
 634                                     ((fl1->share == IPV6_FL_S_USER) &&
 635                                      uid_eq(fl1->owner.uid, fl->owner.uid)))
 636                                         goto release;
 637
 638                                 err = -ENOMEM;
 639                                 if (sfl1 == NULL)
 640                                         goto release;
 641                                 if (fl->linger > fl1->linger)
 642                                         fl1->linger = fl->linger;
 643                                 if ((long)(fl->expires - fl1->expires) > 0)
 644                                         fl1->expires = fl->expires;
 645                                 fl_link(np, sfl1, fl1);
 646                                 fl_free(fl);
 647                                 return 0;
 648
 649 release:
 650                                 fl_release(fl1);
 651                                 goto done;
 652                         }
 653                 }
 654                 err = -ENOENT;
 655                 if (!(freq.flr_flags&IPV6_FL_F_CREATE))
 656                         goto done;
 657
 658                 err = -ENOMEM;
 659                 if (sfl1 == NULL || (err = mem_check(sk)) != 0)
 660                         goto done;
 661
 662                 fl1 = fl_intern(net, fl, freq.flr_label);
 663                 if (fl1 != NULL)
 664                         goto recheck;
 665
 666                 if (!freq.flr_label) {
 667                         if (copy_to_user(&((struct in6_flowlabel_req __user *) optval)->flr_label,
 668                                          &fl->label, sizeof(fl->label))) {
 669                                 /* Intentionally ignore fault. */
 670                         }
 671                 }
 672
 673                 fl_link(np, sfl1, fl);
 674                 return 0;
 675
 676         default:
 677                 return -EINVAL;
 678         }
 679
 680 done:
 681         fl_free(fl);
 682         kfree(sfl1);
 683         return err;
 684 }
 685
 686 #ifdef CONFIG_PROC_FS
 687
 688 struct ip6fl_iter_state {
 689         struct seq_net_private p;
 690         struct pid_namespace *pid_ns;
 691         int bucket;
 692 };
 693
 694 #define ip6fl_seq_private(seq)  ((struct ip6fl_iter_state *)(seq)->private)
 695
 696 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq)
 697 {
 698         struct ip6_flowlabel *fl = NULL;
 699         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
 700         struct net *net = seq_file_net(seq);
 701
 702         for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) {
 703                 for_each_fl_rcu(state->bucket, fl) {
 704                         if (net_eq(fl->fl_net, net))
 705                                 goto out;
 706                 }
 707         }
 708         fl = NULL;
 709 out:
 710         return fl;
 711 }
 712
 713 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl)
 714 {
 715         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
 716         struct net *net = seq_file_net(seq);
 717
 718         for_each_fl_continue_rcu(fl) {
 719                 if (net_eq(fl->fl_net, net))
 720                         goto out;
 721         }
 722
 723 try_again:
 724         if (++state->bucket <= FL_HASH_MASK) {
 725                 for_each_fl_rcu(state->bucket, fl) {
 726                         if (net_eq(fl->fl_net, net))
 727                                 goto out;
 728                 }
 729                 goto try_again;
 730         }
 731         fl = NULL;
 732
 733 out:
 734         return fl;
 735 }
 736
 737 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos)
 738 {
 739         struct ip6_flowlabel *fl = ip6fl_get_first(seq);
 740         if (fl)
 741                 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL)
 742                         --pos;
 743         return pos ? NULL : fl;
 744 }
 745
 746 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos)
 747         __acquires(RCU)
 748 {
 749         rcu_read_lock_bh();
 750         return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN;
 751 }
 752
 753 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos)
 754 {
 755         struct ip6_flowlabel *fl;
 756
 757         if (v == SEQ_START_TOKEN)
 758                 fl = ip6fl_get_first(seq);
 759         else
 760                 fl = ip6fl_get_next(seq, v);
 761         ++*pos;
 762         return fl;
 763 }
 764
 765 static void ip6fl_seq_stop(struct seq_file *seq, void *v)
 766         __releases(RCU)
 767 {
 768         rcu_read_unlock_bh();
 769 }
 770
 771 static int ip6fl_seq_show(struct seq_file *seq, void *v)
 772 {
 773         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
 774         if (v == SEQ_START_TOKEN)
 775                 seq_printf(seq, "%-5s %-1s %-6s %-6s %-6s %-8s %-32s %s\n",
 776                            "Label", "S", "Owner", "Users", "Linger", "Expires", "Dst", "Opt");
 777         else {
 778                 struct ip6_flowlabel *fl = v;
 779                 seq_printf(seq,
 780                            "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n",
 781                            (unsigned int)ntohl(fl->label),
 782                            fl->share,
 783                            ((fl->share == IPV6_FL_S_PROCESS) ?
 784                             pid_nr_ns(fl->owner.pid, state->pid_ns) :
 785                             ((fl->share == IPV6_FL_S_USER) ?
 786                              from_kuid_munged(seq_user_ns(seq), fl->owner.uid) :
 787                              0)),
 788                            atomic_read(&fl->users),
 789                            fl->linger/HZ,
 790                            (long)(fl->expires - jiffies)/HZ,
 791                            &fl->dst,
 792                            fl->opt ? fl->opt->opt_nflen : 0);
 793         }
 794         return 0;
 795 }
 796
 797 static const struct seq_operations ip6fl_seq_ops = {
 798         .start  =       ip6fl_seq_start,
 799         .next   =       ip6fl_seq_next,
 800         .stop   =       ip6fl_seq_stop,
 801         .show   =       ip6fl_seq_show,
 802 };
 803
 804 static int ip6fl_seq_open(struct inode *inode, struct file *file)
 805 {
 806         struct seq_file *seq;
 807         struct ip6fl_iter_state *state;
 808         int err;
 809
 810         err = seq_open_net(inode, file, &ip6fl_seq_ops,
 811                            sizeof(struct ip6fl_iter_state));
 812
 813         if (!err) {
 814                 seq = file->private_data;
 815                 state = ip6fl_seq_private(seq);
 816                 rcu_read_lock();
 817                 state->pid_ns = get_pid_ns(task_active_pid_ns(current));
 818                 rcu_read_unlock();
 819         }
 820         return err;
 821 }
 822
 823 static int ip6fl_seq_release(struct inode *inode, struct file *file)
 824 {
 825         struct seq_file *seq = file->private_data;
 826         struct ip6fl_iter_state *state = ip6fl_seq_private(seq);
 827         put_pid_ns(state->pid_ns);
 828         return seq_release_net(inode, file);
 829 }
 830
 831 static const struct file_operations ip6fl_seq_fops = {
 832         .owner          =       THIS_MODULE,
 833         .open           =       ip6fl_seq_open,
 834         .read           =       seq_read,
 835         .llseek         =       seq_lseek,
 836         .release        =       ip6fl_seq_release,
 837 };
 838
 839 static int __net_init ip6_flowlabel_proc_init(struct net *net)
 840 {
 841         if (!proc_create("ip6_flowlabel", S_IRUGO, net->proc_net,
 842                          &ip6fl_seq_fops))
 843                 return -ENOMEM;
 844         return 0;
 845 }
 846
 847 static void __net_exit ip6_flowlabel_proc_fini(struct net *net)
 848 {
 849         remove_proc_entry("ip6_flowlabel", net->proc_net);
 850 }
 851 #else
 852 static inline int ip6_flowlabel_proc_init(struct net *net)
 853 {
 854         return 0;
 855 }
 856 static inline void ip6_flowlabel_proc_fini(struct net *net)
 857 {
 858 }
 859 #endif
 860
 861 static void __net_exit ip6_flowlabel_net_exit(struct net *net)
 862 {
 863         ip6_fl_purge(net);
 864         ip6_flowlabel_proc_fini(net);
 865 }
 866
 867 static struct pernet_operations ip6_flowlabel_net_ops = {
 868         .init = ip6_flowlabel_proc_init,
 869         .exit = ip6_flowlabel_net_exit,
 870 };
 871
 872 int ip6_flowlabel_init(void)
 873 {
 874         return register_pernet_subsys(&ip6_flowlabel_net_ops);
 875 }
 876
 877 void ip6_flowlabel_cleanup(void)
 878 {
 879         del_timer(&ip6_fl_gc_timer);
 880         unregister_pernet_subsys(&ip6_flowlabel_net_ops);
 881 }