1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * ip6_flowlabel.c IPv6 flowlabel manager. 4 * 5 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> 6 */ 7 8 #include <linux/capability.h> 9 #include <linux/errno.h> 10 #include <linux/types.h> 11 #include <linux/socket.h> 12 #include <linux/net.h> 13 #include <linux/netdevice.h> 14 #include <linux/in6.h> 15 #include <linux/proc_fs.h> 16 #include <linux/seq_file.h> 17 #include <linux/slab.h> 18 #include <linux/export.h> 19 #include <linux/pid_namespace.h> 20 #include <linux/jump_label_ratelimit.h> 21 22 #include <net/net_namespace.h> 23 #include <net/sock.h> 24 25 #include <net/ipv6.h> 26 #include <net/rawv6.h> 27 #include <net/transp_v6.h> 28 29 #include <linux/uaccess.h> 30 31 #define FL_MIN_LINGER 6 /* Minimal linger. It is set to 6sec specified 32 in old IPv6 RFC. Well, it was reasonable value. 33 */ 34 #define FL_MAX_LINGER 150 /* Maximal linger timeout */ 35 36 /* FL hash table */ 37 38 #define FL_MAX_PER_SOCK 32 39 #define FL_MAX_SIZE 4096 40 #define FL_HASH_MASK 255 41 #define FL_HASH(l) (ntohl(l)&FL_HASH_MASK) 42 43 static atomic_t fl_size = ATOMIC_INIT(0); 44 static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1]; 45 46 static void ip6_fl_gc(struct timer_list *unused); 47 static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc); 48 49 /* FL hash table lock: it protects only of GC */ 50 51 static DEFINE_SPINLOCK(ip6_fl_lock); 52 53 /* Big socket sock */ 54 55 static DEFINE_SPINLOCK(ip6_sk_fl_lock); 56 57 DEFINE_STATIC_KEY_DEFERRED_FALSE(ipv6_flowlabel_exclusive, HZ); 58 EXPORT_SYMBOL(ipv6_flowlabel_exclusive); 59 60 #define for_each_fl_rcu(hash, fl) \ 61 for (fl = rcu_dereference(fl_ht[(hash)]); \ 62 fl != NULL; \ 63 fl = rcu_dereference(fl->next)) 64 #define for_each_fl_continue_rcu(fl) \ 65 for (fl = rcu_dereference(fl->next); \ 66 fl != NULL; \ 67 fl = rcu_dereference(fl->next)) 68 69 #define for_each_sk_fl_rcu(sk, sfl) \ 70 for (sfl = rcu_dereference(inet_sk(sk)->ipv6_fl_list); \ 71 sfl != NULL; \ 72 sfl = rcu_dereference(sfl->next)) 73 74 static inline struct ip6_flowlabel *__fl_lookup(struct net *net, __be32 label) 75 { 76 struct ip6_flowlabel *fl; 77 78 for_each_fl_rcu(FL_HASH(label), fl) { 79 if (fl->label == label && net_eq(fl->fl_net, net)) 80 return fl; 81 } 82 return NULL; 83 } 84 85 static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label) 86 { 87 struct ip6_flowlabel *fl; 88 89 rcu_read_lock(); 90 fl = __fl_lookup(net, label); 91 if (fl && !atomic_inc_not_zero(&fl->users)) 92 fl = NULL; 93 rcu_read_unlock(); 94 return fl; 95 } 96 97 static bool fl_shared_exclusive(struct ip6_flowlabel *fl) 98 { 99 return fl->share == IPV6_FL_S_EXCL || 100 fl->share == IPV6_FL_S_PROCESS || 101 fl->share == IPV6_FL_S_USER; 102 } 103 104 static void fl_free_rcu(struct rcu_head *head) 105 { 106 struct ip6_flowlabel *fl = container_of(head, struct ip6_flowlabel, rcu); 107 108 if (fl->share == IPV6_FL_S_PROCESS) 109 put_pid(fl->owner.pid); 110 kfree(fl->opt); 111 kfree(fl); 112 } 113 114 115 static void fl_free(struct ip6_flowlabel *fl) 116 { 117 if (!fl) 118 return; 119 120 if (fl_shared_exclusive(fl) || fl->opt) 121 static_branch_slow_dec_deferred(&ipv6_flowlabel_exclusive); 122 123 call_rcu(&fl->rcu, fl_free_rcu); 124 } 125 126 static void fl_release(struct ip6_flowlabel *fl) 127 { 128 spin_lock_bh(&ip6_fl_lock); 129 130 fl->lastuse = jiffies; 131 if (atomic_dec_and_test(&fl->users)) { 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 (fl->opt && fl->share == IPV6_FL_S_EXCL) { 137 struct ipv6_txoptions *opt = fl->opt; 138 fl->opt = NULL; 139 kfree(opt); 140 } 141 if (!timer_pending(&ip6_fl_gc_timer) || 142 time_after(ip6_fl_gc_timer.expires, ttd)) 143 mod_timer(&ip6_fl_gc_timer, ttd); 144 } 145 spin_unlock_bh(&ip6_fl_lock); 146 } 147 148 static void ip6_fl_gc(struct timer_list *unused) 149 { 150 int i; 151 unsigned long now = jiffies; 152 unsigned long sched = 0; 153 154 spin_lock(&ip6_fl_lock); 155 156 for (i = 0; i <= FL_HASH_MASK; i++) { 157 struct ip6_flowlabel *fl; 158 struct ip6_flowlabel __rcu **flp; 159 160 flp = &fl_ht[i]; 161 while ((fl = rcu_dereference_protected(*flp, 162 lockdep_is_held(&ip6_fl_lock))) != NULL) { 163 if (atomic_read(&fl->users) == 0) { 164 unsigned long ttd = fl->lastuse + fl->linger; 165 if (time_after(ttd, fl->expires)) 166 fl->expires = ttd; 167 ttd = fl->expires; 168 if (time_after_eq(now, ttd)) { 169 *flp = fl->next; 170 fl_free(fl); 171 atomic_dec(&fl_size); 172 continue; 173 } 174 if (!sched || time_before(ttd, sched)) 175 sched = ttd; 176 } 177 flp = &fl->next; 178 } 179 } 180 if (!sched && atomic_read(&fl_size)) 181 sched = now + FL_MAX_LINGER; 182 if (sched) { 183 mod_timer(&ip6_fl_gc_timer, sched); 184 } 185 spin_unlock(&ip6_fl_lock); 186 } 187 188 static void __net_exit ip6_fl_purge(struct net *net) 189 { 190 int i; 191 192 spin_lock_bh(&ip6_fl_lock); 193 for (i = 0; i <= FL_HASH_MASK; i++) { 194 struct ip6_flowlabel *fl; 195 struct ip6_flowlabel __rcu **flp; 196 197 flp = &fl_ht[i]; 198 while ((fl = rcu_dereference_protected(*flp, 199 lockdep_is_held(&ip6_fl_lock))) != NULL) { 200 if (net_eq(fl->fl_net, net) && 201 atomic_read(&fl->users) == 0) { 202 *flp = fl->next; 203 fl_free(fl); 204 atomic_dec(&fl_size); 205 continue; 206 } 207 flp = &fl->next; 208 } 209 } 210 spin_unlock_bh(&ip6_fl_lock); 211 } 212 213 static struct ip6_flowlabel *fl_intern(struct net *net, 214 struct ip6_flowlabel *fl, __be32 label) 215 { 216 struct ip6_flowlabel *lfl; 217 218 fl->label = label & IPV6_FLOWLABEL_MASK; 219 220 rcu_read_lock(); 221 spin_lock_bh(&ip6_fl_lock); 222 if (label == 0) { 223 for (;;) { 224 fl->label = htonl(get_random_u32())&IPV6_FLOWLABEL_MASK; 225 if (fl->label) { 226 lfl = __fl_lookup(net, fl->label); 227 if (!lfl) 228 break; 229 } 230 } 231 } else { 232 /* 233 * we dropper the ip6_fl_lock, so this entry could reappear 234 * and we need to recheck with it. 235 * 236 * OTOH no need to search the active socket first, like it is 237 * done in ipv6_flowlabel_opt - sock is locked, so new entry 238 * with the same label can only appear on another sock 239 */ 240 lfl = __fl_lookup(net, fl->label); 241 if (lfl) { 242 atomic_inc(&lfl->users); 243 spin_unlock_bh(&ip6_fl_lock); 244 rcu_read_unlock(); 245 return lfl; 246 } 247 } 248 249 fl->lastuse = jiffies; 250 fl->next = fl_ht[FL_HASH(fl->label)]; 251 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl); 252 atomic_inc(&fl_size); 253 spin_unlock_bh(&ip6_fl_lock); 254 rcu_read_unlock(); 255 return NULL; 256 } 257 258 259 260 /* Socket flowlabel lists */ 261 262 struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label) 263 { 264 struct ipv6_fl_socklist *sfl; 265 266 label &= IPV6_FLOWLABEL_MASK; 267 268 rcu_read_lock(); 269 for_each_sk_fl_rcu(sk, sfl) { 270 struct ip6_flowlabel *fl = sfl->fl; 271 272 if (fl->label == label && atomic_inc_not_zero(&fl->users)) { 273 fl->lastuse = jiffies; 274 rcu_read_unlock(); 275 return fl; 276 } 277 } 278 rcu_read_unlock(); 279 return NULL; 280 } 281 EXPORT_SYMBOL_GPL(__fl6_sock_lookup); 282 283 void fl6_free_socklist(struct sock *sk) 284 { 285 struct inet_sock *inet = inet_sk(sk); 286 struct ipv6_fl_socklist *sfl; 287 288 if (!rcu_access_pointer(inet->ipv6_fl_list)) 289 return; 290 291 spin_lock_bh(&ip6_sk_fl_lock); 292 while ((sfl = rcu_dereference_protected(inet->ipv6_fl_list, 293 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 294 inet->ipv6_fl_list = sfl->next; 295 spin_unlock_bh(&ip6_sk_fl_lock); 296 297 fl_release(sfl->fl); 298 kfree_rcu(sfl, rcu); 299 300 spin_lock_bh(&ip6_sk_fl_lock); 301 } 302 spin_unlock_bh(&ip6_sk_fl_lock); 303 } 304 305 /* Service routines */ 306 307 308 /* 309 It is the only difficult place. flowlabel enforces equal headers 310 before and including routing header, however user may supply options 311 following rthdr. 312 */ 313 314 struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 315 struct ip6_flowlabel *fl, 316 struct ipv6_txoptions *fopt) 317 { 318 struct ipv6_txoptions *fl_opt = fl->opt; 319 320 if (!fopt || fopt->opt_flen == 0) 321 return fl_opt; 322 323 if (fl_opt) { 324 opt_space->hopopt = fl_opt->hopopt; 325 opt_space->dst0opt = fl_opt->dst0opt; 326 opt_space->srcrt = fl_opt->srcrt; 327 opt_space->opt_nflen = fl_opt->opt_nflen; 328 } else { 329 if (fopt->opt_nflen == 0) 330 return fopt; 331 opt_space->hopopt = NULL; 332 opt_space->dst0opt = NULL; 333 opt_space->srcrt = NULL; 334 opt_space->opt_nflen = 0; 335 } 336 opt_space->dst1opt = fopt->dst1opt; 337 opt_space->opt_flen = fopt->opt_flen; 338 opt_space->tot_len = fopt->tot_len; 339 return opt_space; 340 } 341 EXPORT_SYMBOL_GPL(fl6_merge_options); 342 343 static unsigned long check_linger(unsigned long ttl) 344 { 345 if (ttl < FL_MIN_LINGER) 346 return FL_MIN_LINGER*HZ; 347 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 348 return 0; 349 return ttl*HZ; 350 } 351 352 static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 353 { 354 linger = check_linger(linger); 355 if (!linger) 356 return -EPERM; 357 expires = check_linger(expires); 358 if (!expires) 359 return -EPERM; 360 361 spin_lock_bh(&ip6_fl_lock); 362 fl->lastuse = jiffies; 363 if (time_before(fl->linger, linger)) 364 fl->linger = linger; 365 if (time_before(expires, fl->linger)) 366 expires = fl->linger; 367 if (time_before(fl->expires, fl->lastuse + expires)) 368 fl->expires = fl->lastuse + expires; 369 spin_unlock_bh(&ip6_fl_lock); 370 371 return 0; 372 } 373 374 static struct ip6_flowlabel * 375 fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 376 sockptr_t optval, int optlen, int *err_p) 377 { 378 struct ip6_flowlabel *fl = NULL; 379 int olen; 380 int addr_type; 381 int err; 382 383 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 384 err = -EINVAL; 385 if (olen > 64 * 1024) 386 goto done; 387 388 err = -ENOMEM; 389 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 390 if (!fl) 391 goto done; 392 393 if (olen > 0) { 394 struct msghdr msg; 395 struct flowi6 flowi6; 396 struct ipcm6_cookie ipc6; 397 398 err = -ENOMEM; 399 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 400 if (!fl->opt) 401 goto done; 402 403 memset(fl->opt, 0, sizeof(*fl->opt)); 404 fl->opt->tot_len = sizeof(*fl->opt) + olen; 405 err = -EFAULT; 406 if (copy_from_sockptr_offset(fl->opt + 1, optval, 407 CMSG_ALIGN(sizeof(*freq)), olen)) 408 goto done; 409 410 msg.msg_controllen = olen; 411 msg.msg_control = (void *)(fl->opt+1); 412 memset(&flowi6, 0, sizeof(flowi6)); 413 414 ipc6.opt = fl->opt; 415 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, &ipc6); 416 if (err) 417 goto done; 418 err = -EINVAL; 419 if (fl->opt->opt_flen) 420 goto done; 421 if (fl->opt->opt_nflen == 0) { 422 kfree(fl->opt); 423 fl->opt = NULL; 424 } 425 } 426 427 fl->fl_net = net; 428 fl->expires = jiffies; 429 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires); 430 if (err) 431 goto done; 432 fl->share = freq->flr_share; 433 addr_type = ipv6_addr_type(&freq->flr_dst); 434 if ((addr_type & IPV6_ADDR_MAPPED) || 435 addr_type == IPV6_ADDR_ANY) { 436 err = -EINVAL; 437 goto done; 438 } 439 fl->dst = freq->flr_dst; 440 atomic_set(&fl->users, 1); 441 switch (fl->share) { 442 case IPV6_FL_S_EXCL: 443 case IPV6_FL_S_ANY: 444 break; 445 case IPV6_FL_S_PROCESS: 446 fl->owner.pid = get_task_pid(current, PIDTYPE_PID); 447 break; 448 case IPV6_FL_S_USER: 449 fl->owner.uid = current_euid(); 450 break; 451 default: 452 err = -EINVAL; 453 goto done; 454 } 455 if (fl_shared_exclusive(fl) || fl->opt) { 456 WRITE_ONCE(sock_net(sk)->ipv6.flowlabel_has_excl, 1); 457 static_branch_deferred_inc(&ipv6_flowlabel_exclusive); 458 } 459 return fl; 460 461 done: 462 if (fl) { 463 kfree(fl->opt); 464 kfree(fl); 465 } 466 *err_p = err; 467 return NULL; 468 } 469 470 static int mem_check(struct sock *sk) 471 { 472 int room = FL_MAX_SIZE - atomic_read(&fl_size); 473 struct ipv6_fl_socklist *sfl; 474 int count = 0; 475 476 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK) 477 return 0; 478 479 rcu_read_lock(); 480 for_each_sk_fl_rcu(sk, sfl) 481 count++; 482 rcu_read_unlock(); 483 484 if (room <= 0 || 485 ((count >= FL_MAX_PER_SOCK || 486 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) && 487 !capable(CAP_NET_ADMIN))) 488 return -ENOBUFS; 489 490 return 0; 491 } 492 493 static inline void fl_link(struct sock *sk, struct ipv6_fl_socklist *sfl, 494 struct ip6_flowlabel *fl) 495 { 496 struct inet_sock *inet = inet_sk(sk); 497 498 spin_lock_bh(&ip6_sk_fl_lock); 499 sfl->fl = fl; 500 sfl->next = inet->ipv6_fl_list; 501 rcu_assign_pointer(inet->ipv6_fl_list, sfl); 502 spin_unlock_bh(&ip6_sk_fl_lock); 503 } 504 505 int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 506 int flags) 507 { 508 struct ipv6_pinfo *np = inet6_sk(sk); 509 struct ipv6_fl_socklist *sfl; 510 511 if (flags & IPV6_FL_F_REMOTE) { 512 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK; 513 return 0; 514 } 515 516 if (inet6_test_bit(REPFLOW, sk)) { 517 freq->flr_label = np->flow_label; 518 return 0; 519 } 520 521 rcu_read_lock(); 522 523 for_each_sk_fl_rcu(sk, sfl) { 524 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) { 525 spin_lock_bh(&ip6_fl_lock); 526 freq->flr_label = sfl->fl->label; 527 freq->flr_dst = sfl->fl->dst; 528 freq->flr_share = sfl->fl->share; 529 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ; 530 freq->flr_linger = sfl->fl->linger / HZ; 531 532 spin_unlock_bh(&ip6_fl_lock); 533 rcu_read_unlock(); 534 return 0; 535 } 536 } 537 rcu_read_unlock(); 538 539 return -ENOENT; 540 } 541 542 #define socklist_dereference(__sflp) \ 543 rcu_dereference_protected(__sflp, lockdep_is_held(&ip6_sk_fl_lock)) 544 545 static int ipv6_flowlabel_put(struct sock *sk, struct in6_flowlabel_req *freq) 546 { 547 struct ipv6_pinfo *np = inet6_sk(sk); 548 struct ipv6_fl_socklist __rcu **sflp; 549 struct ipv6_fl_socklist *sfl; 550 551 if (freq->flr_flags & IPV6_FL_F_REFLECT) { 552 if (sk->sk_protocol != IPPROTO_TCP) 553 return -ENOPROTOOPT; 554 if (!inet6_test_bit(REPFLOW, sk)) 555 return -ESRCH; 556 np->flow_label = 0; 557 inet6_clear_bit(REPFLOW, sk); 558 return 0; 559 } 560 561 spin_lock_bh(&ip6_sk_fl_lock); 562 for (sflp = &inet_sk(sk)->ipv6_fl_list; 563 (sfl = socklist_dereference(*sflp)) != NULL; 564 sflp = &sfl->next) { 565 if (sfl->fl->label == freq->flr_label) 566 goto found; 567 } 568 spin_unlock_bh(&ip6_sk_fl_lock); 569 return -ESRCH; 570 found: 571 if (freq->flr_label == (np->flow_label & IPV6_FLOWLABEL_MASK)) 572 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 573 *sflp = sfl->next; 574 spin_unlock_bh(&ip6_sk_fl_lock); 575 fl_release(sfl->fl); 576 kfree_rcu(sfl, rcu); 577 return 0; 578 } 579 580 static int ipv6_flowlabel_renew(struct sock *sk, struct in6_flowlabel_req *freq) 581 { 582 struct net *net = sock_net(sk); 583 struct ipv6_fl_socklist *sfl; 584 int err; 585 586 rcu_read_lock(); 587 for_each_sk_fl_rcu(sk, sfl) { 588 if (sfl->fl->label == freq->flr_label) { 589 err = fl6_renew(sfl->fl, freq->flr_linger, 590 freq->flr_expires); 591 rcu_read_unlock(); 592 return err; 593 } 594 } 595 rcu_read_unlock(); 596 597 if (freq->flr_share == IPV6_FL_S_NONE && 598 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 599 struct ip6_flowlabel *fl = fl_lookup(net, freq->flr_label); 600 601 if (fl) { 602 err = fl6_renew(fl, freq->flr_linger, 603 freq->flr_expires); 604 fl_release(fl); 605 return err; 606 } 607 } 608 return -ESRCH; 609 } 610 611 static int ipv6_flowlabel_get(struct sock *sk, struct in6_flowlabel_req *freq, 612 sockptr_t optval, int optlen) 613 { 614 struct ipv6_fl_socklist *sfl, *sfl1 = NULL; 615 struct ip6_flowlabel *fl, *fl1 = NULL; 616 struct net *net = sock_net(sk); 617 int err; 618 619 if (freq->flr_flags & IPV6_FL_F_REFLECT) { 620 if (net->ipv6.sysctl.flowlabel_consistency) { 621 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n"); 622 return -EPERM; 623 } 624 625 if (sk->sk_protocol != IPPROTO_TCP) 626 return -ENOPROTOOPT; 627 inet6_set_bit(REPFLOW, sk); 628 return 0; 629 } 630 631 if (freq->flr_label & ~IPV6_FLOWLABEL_MASK) 632 return -EINVAL; 633 if (net->ipv6.sysctl.flowlabel_state_ranges && 634 (freq->flr_label & IPV6_FLOWLABEL_STATELESS_FLAG)) 635 return -ERANGE; 636 637 fl = fl_create(net, sk, freq, optval, optlen, &err); 638 if (!fl) 639 return err; 640 641 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 642 643 if (freq->flr_label) { 644 err = -EEXIST; 645 rcu_read_lock(); 646 for_each_sk_fl_rcu(sk, sfl) { 647 if (sfl->fl->label == freq->flr_label) { 648 if (freq->flr_flags & IPV6_FL_F_EXCL) { 649 rcu_read_unlock(); 650 goto done; 651 } 652 fl1 = sfl->fl; 653 if (!atomic_inc_not_zero(&fl1->users)) 654 fl1 = NULL; 655 break; 656 } 657 } 658 rcu_read_unlock(); 659 660 if (!fl1) 661 fl1 = fl_lookup(net, freq->flr_label); 662 if (fl1) { 663 recheck: 664 err = -EEXIST; 665 if (freq->flr_flags&IPV6_FL_F_EXCL) 666 goto release; 667 err = -EPERM; 668 if (fl1->share == IPV6_FL_S_EXCL || 669 fl1->share != fl->share || 670 ((fl1->share == IPV6_FL_S_PROCESS) && 671 (fl1->owner.pid != fl->owner.pid)) || 672 ((fl1->share == IPV6_FL_S_USER) && 673 !uid_eq(fl1->owner.uid, fl->owner.uid))) 674 goto release; 675 676 err = -ENOMEM; 677 if (!sfl1) 678 goto release; 679 if (fl->linger > fl1->linger) 680 fl1->linger = fl->linger; 681 if ((long)(fl->expires - fl1->expires) > 0) 682 fl1->expires = fl->expires; 683 fl_link(sk, sfl1, fl1); 684 fl_free(fl); 685 return 0; 686 687 release: 688 fl_release(fl1); 689 goto done; 690 } 691 } 692 err = -ENOENT; 693 if (!(freq->flr_flags & IPV6_FL_F_CREATE)) 694 goto done; 695 696 err = -ENOMEM; 697 if (!sfl1) 698 goto done; 699 700 err = mem_check(sk); 701 if (err != 0) 702 goto done; 703 704 fl1 = fl_intern(net, fl, freq->flr_label); 705 if (fl1) 706 goto recheck; 707 708 if (!freq->flr_label) { 709 size_t offset = offsetof(struct in6_flowlabel_req, flr_label); 710 711 if (copy_to_sockptr_offset(optval, offset, &fl->label, 712 sizeof(fl->label))) { 713 /* Intentionally ignore fault. */ 714 } 715 } 716 717 fl_link(sk, sfl1, fl); 718 return 0; 719 done: 720 fl_free(fl); 721 kfree(sfl1); 722 return err; 723 } 724 725 int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen) 726 { 727 struct in6_flowlabel_req freq; 728 729 if (optlen < sizeof(freq)) 730 return -EINVAL; 731 if (copy_from_sockptr(&freq, optval, sizeof(freq))) 732 return -EFAULT; 733 734 switch (freq.flr_action) { 735 case IPV6_FL_A_PUT: 736 return ipv6_flowlabel_put(sk, &freq); 737 case IPV6_FL_A_RENEW: 738 return ipv6_flowlabel_renew(sk, &freq); 739 case IPV6_FL_A_GET: 740 return ipv6_flowlabel_get(sk, &freq, optval, optlen); 741 default: 742 return -EINVAL; 743 } 744 } 745 746 #ifdef CONFIG_PROC_FS 747 748 struct ip6fl_iter_state { 749 struct seq_net_private p; 750 struct pid_namespace *pid_ns; 751 int bucket; 752 }; 753 754 #define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 755 756 static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 757 { 758 struct ip6_flowlabel *fl = NULL; 759 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 760 struct net *net = seq_file_net(seq); 761 762 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 763 for_each_fl_rcu(state->bucket, fl) { 764 if (net_eq(fl->fl_net, net)) 765 goto out; 766 } 767 } 768 fl = NULL; 769 out: 770 return fl; 771 } 772 773 static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 774 { 775 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 776 struct net *net = seq_file_net(seq); 777 778 for_each_fl_continue_rcu(fl) { 779 if (net_eq(fl->fl_net, net)) 780 goto out; 781 } 782 783 try_again: 784 if (++state->bucket <= FL_HASH_MASK) { 785 for_each_fl_rcu(state->bucket, fl) { 786 if (net_eq(fl->fl_net, net)) 787 goto out; 788 } 789 goto try_again; 790 } 791 fl = NULL; 792 793 out: 794 return fl; 795 } 796 797 static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 798 { 799 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 800 if (fl) 801 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 802 --pos; 803 return pos ? NULL : fl; 804 } 805 806 static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 807 __acquires(RCU) 808 { 809 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 810 811 state->pid_ns = proc_pid_ns(file_inode(seq->file)->i_sb); 812 813 rcu_read_lock(); 814 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 815 } 816 817 static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 818 { 819 struct ip6_flowlabel *fl; 820 821 if (v == SEQ_START_TOKEN) 822 fl = ip6fl_get_first(seq); 823 else 824 fl = ip6fl_get_next(seq, v); 825 ++*pos; 826 return fl; 827 } 828 829 static void ip6fl_seq_stop(struct seq_file *seq, void *v) 830 __releases(RCU) 831 { 832 rcu_read_unlock(); 833 } 834 835 static int ip6fl_seq_show(struct seq_file *seq, void *v) 836 { 837 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 838 if (v == SEQ_START_TOKEN) { 839 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n"); 840 } else { 841 struct ip6_flowlabel *fl = v; 842 seq_printf(seq, 843 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 844 (unsigned int)ntohl(fl->label), 845 fl->share, 846 ((fl->share == IPV6_FL_S_PROCESS) ? 847 pid_nr_ns(fl->owner.pid, state->pid_ns) : 848 ((fl->share == IPV6_FL_S_USER) ? 849 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 850 0)), 851 atomic_read(&fl->users), 852 fl->linger/HZ, 853 (long)(fl->expires - jiffies)/HZ, 854 &fl->dst, 855 fl->opt ? fl->opt->opt_nflen : 0); 856 } 857 return 0; 858 } 859 860 static const struct seq_operations ip6fl_seq_ops = { 861 .start = ip6fl_seq_start, 862 .next = ip6fl_seq_next, 863 .stop = ip6fl_seq_stop, 864 .show = ip6fl_seq_show, 865 }; 866 867 static int __net_init ip6_flowlabel_proc_init(struct net *net) 868 { 869 if (!proc_create_net("ip6_flowlabel", 0444, net->proc_net, 870 &ip6fl_seq_ops, sizeof(struct ip6fl_iter_state))) 871 return -ENOMEM; 872 return 0; 873 } 874 875 static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 876 { 877 remove_proc_entry("ip6_flowlabel", net->proc_net); 878 } 879 #else 880 static inline int ip6_flowlabel_proc_init(struct net *net) 881 { 882 return 0; 883 } 884 static inline void ip6_flowlabel_proc_fini(struct net *net) 885 { 886 } 887 #endif 888 889 static void __net_exit ip6_flowlabel_net_exit(struct net *net) 890 { 891 ip6_fl_purge(net); 892 ip6_flowlabel_proc_fini(net); 893 } 894 895 static struct pernet_operations ip6_flowlabel_net_ops = { 896 .init = ip6_flowlabel_proc_init, 897 .exit = ip6_flowlabel_net_exit, 898 }; 899 900 int ip6_flowlabel_init(void) 901 { 902 return register_pernet_subsys(&ip6_flowlabel_net_ops); 903 } 904 905 void ip6_flowlabel_cleanup(void) 906 { 907 static_key_deferred_flush(&ipv6_flowlabel_exclusive); 908 timer_delete(&ip6_fl_gc_timer); 909 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 910 } 911