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 43static atomic_t fl_size = ATOMIC_INIT(0); 44static struct ip6_flowlabel __rcu *fl_ht[FL_HASH_MASK+1]; 45 46static void ip6_fl_gc(struct timer_list *unused); 47static DEFINE_TIMER(ip6_fl_gc_timer, ip6_fl_gc); 48 49/* FL hash table lock: it protects only of GC */ 50 51static DEFINE_SPINLOCK(ip6_fl_lock); 52 53/* Big socket sock */ 54 55static DEFINE_SPINLOCK(ip6_sk_fl_lock); 56 57DEFINE_STATIC_KEY_DEFERRED_FALSE(ipv6_flowlabel_exclusive, HZ); 58EXPORT_SYMBOL(ipv6_flowlabel_exclusive); 59 60#define for_each_fl_rcu(hash, fl) \ 61 for (fl = rcu_dereference_bh(fl_ht[(hash)]); \ 62 fl != NULL; \ 63 fl = rcu_dereference_bh(fl->next)) 64#define for_each_fl_continue_rcu(fl) \ 65 for (fl = rcu_dereference_bh(fl->next); \ 66 fl != NULL; \ 67 fl = rcu_dereference_bh(fl->next)) 68 69#define for_each_sk_fl_rcu(np, sfl) \ 70 for (sfl = rcu_dereference_bh(np->ipv6_fl_list); \ 71 sfl != NULL; \ 72 sfl = rcu_dereference_bh(sfl->next)) 73 74static 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 85static struct ip6_flowlabel *fl_lookup(struct net *net, __be32 label) 86{ 87 struct ip6_flowlabel *fl; 88 89 rcu_read_lock_bh(); 90 fl = __fl_lookup(net, label); 91 if (fl && !atomic_inc_not_zero(&fl->users)) 92 fl = NULL; 93 rcu_read_unlock_bh(); 94 return fl; 95} 96 97static 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 104static 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 115static 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 126static 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 148static 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 188static 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 213static 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 spin_lock_bh(&ip6_fl_lock); 221 if (label == 0) { 222 for (;;) { 223 fl->label = htonl(prandom_u32())&IPV6_FLOWLABEL_MASK; 224 if (fl->label) { 225 lfl = __fl_lookup(net, fl->label); 226 if (!lfl) 227 break; 228 } 229 } 230 } else { 231 /* 232 * we dropper the ip6_fl_lock, so this entry could reappear 233 * and we need to recheck with it. 234 * 235 * OTOH no need to search the active socket first, like it is 236 * done in ipv6_flowlabel_opt - sock is locked, so new entry 237 * with the same label can only appear on another sock 238 */ 239 lfl = __fl_lookup(net, fl->label); 240 if (lfl) { 241 atomic_inc(&lfl->users); 242 spin_unlock_bh(&ip6_fl_lock); 243 return lfl; 244 } 245 } 246 247 fl->lastuse = jiffies; 248 fl->next = fl_ht[FL_HASH(fl->label)]; 249 rcu_assign_pointer(fl_ht[FL_HASH(fl->label)], fl); 250 atomic_inc(&fl_size); 251 spin_unlock_bh(&ip6_fl_lock); 252 return NULL; 253} 254 255 256 257/* Socket flowlabel lists */ 258 259struct ip6_flowlabel *__fl6_sock_lookup(struct sock *sk, __be32 label) 260{ 261 struct ipv6_fl_socklist *sfl; 262 struct ipv6_pinfo *np = inet6_sk(sk); 263 264 label &= IPV6_FLOWLABEL_MASK; 265 266 rcu_read_lock_bh(); 267 for_each_sk_fl_rcu(np, sfl) { 268 struct ip6_flowlabel *fl = sfl->fl; 269 270 if (fl->label == label && atomic_inc_not_zero(&fl->users)) { 271 fl->lastuse = jiffies; 272 rcu_read_unlock_bh(); 273 return fl; 274 } 275 } 276 rcu_read_unlock_bh(); 277 return NULL; 278} 279EXPORT_SYMBOL_GPL(__fl6_sock_lookup); 280 281void fl6_free_socklist(struct sock *sk) 282{ 283 struct ipv6_pinfo *np = inet6_sk(sk); 284 struct ipv6_fl_socklist *sfl; 285 286 if (!rcu_access_pointer(np->ipv6_fl_list)) 287 return; 288 289 spin_lock_bh(&ip6_sk_fl_lock); 290 while ((sfl = rcu_dereference_protected(np->ipv6_fl_list, 291 lockdep_is_held(&ip6_sk_fl_lock))) != NULL) { 292 np->ipv6_fl_list = sfl->next; 293 spin_unlock_bh(&ip6_sk_fl_lock); 294 295 fl_release(sfl->fl); 296 kfree_rcu(sfl, rcu); 297 298 spin_lock_bh(&ip6_sk_fl_lock); 299 } 300 spin_unlock_bh(&ip6_sk_fl_lock); 301} 302 303/* Service routines */ 304 305 306/* 307 It is the only difficult place. flowlabel enforces equal headers 308 before and including routing header, however user may supply options 309 following rthdr. 310 */ 311 312struct ipv6_txoptions *fl6_merge_options(struct ipv6_txoptions *opt_space, 313 struct ip6_flowlabel *fl, 314 struct ipv6_txoptions *fopt) 315{ 316 struct ipv6_txoptions *fl_opt = fl->opt; 317 318 if (!fopt || fopt->opt_flen == 0) 319 return fl_opt; 320 321 if (fl_opt) { 322 opt_space->hopopt = fl_opt->hopopt; 323 opt_space->dst0opt = fl_opt->dst0opt; 324 opt_space->srcrt = fl_opt->srcrt; 325 opt_space->opt_nflen = fl_opt->opt_nflen; 326 } else { 327 if (fopt->opt_nflen == 0) 328 return fopt; 329 opt_space->hopopt = NULL; 330 opt_space->dst0opt = NULL; 331 opt_space->srcrt = NULL; 332 opt_space->opt_nflen = 0; 333 } 334 opt_space->dst1opt = fopt->dst1opt; 335 opt_space->opt_flen = fopt->opt_flen; 336 opt_space->tot_len = fopt->tot_len; 337 return opt_space; 338} 339EXPORT_SYMBOL_GPL(fl6_merge_options); 340 341static unsigned long check_linger(unsigned long ttl) 342{ 343 if (ttl < FL_MIN_LINGER) 344 return FL_MIN_LINGER*HZ; 345 if (ttl > FL_MAX_LINGER && !capable(CAP_NET_ADMIN)) 346 return 0; 347 return ttl*HZ; 348} 349 350static int fl6_renew(struct ip6_flowlabel *fl, unsigned long linger, unsigned long expires) 351{ 352 linger = check_linger(linger); 353 if (!linger) 354 return -EPERM; 355 expires = check_linger(expires); 356 if (!expires) 357 return -EPERM; 358 359 spin_lock_bh(&ip6_fl_lock); 360 fl->lastuse = jiffies; 361 if (time_before(fl->linger, linger)) 362 fl->linger = linger; 363 if (time_before(expires, fl->linger)) 364 expires = fl->linger; 365 if (time_before(fl->expires, fl->lastuse + expires)) 366 fl->expires = fl->lastuse + expires; 367 spin_unlock_bh(&ip6_fl_lock); 368 369 return 0; 370} 371 372static struct ip6_flowlabel * 373fl_create(struct net *net, struct sock *sk, struct in6_flowlabel_req *freq, 374 sockptr_t optval, int optlen, int *err_p) 375{ 376 struct ip6_flowlabel *fl = NULL; 377 int olen; 378 int addr_type; 379 int err; 380 381 olen = optlen - CMSG_ALIGN(sizeof(*freq)); 382 err = -EINVAL; 383 if (olen > 64 * 1024) 384 goto done; 385 386 err = -ENOMEM; 387 fl = kzalloc(sizeof(*fl), GFP_KERNEL); 388 if (!fl) 389 goto done; 390 391 if (olen > 0) { 392 struct msghdr msg; 393 struct flowi6 flowi6; 394 struct ipcm6_cookie ipc6; 395 396 err = -ENOMEM; 397 fl->opt = kmalloc(sizeof(*fl->opt) + olen, GFP_KERNEL); 398 if (!fl->opt) 399 goto done; 400 401 memset(fl->opt, 0, sizeof(*fl->opt)); 402 fl->opt->tot_len = sizeof(*fl->opt) + olen; 403 err = -EFAULT; 404 if (copy_from_sockptr_offset(fl->opt + 1, optval, 405 CMSG_ALIGN(sizeof(*freq)), olen)) 406 goto done; 407 408 msg.msg_controllen = olen; 409 msg.msg_control = (void *)(fl->opt+1); 410 memset(&flowi6, 0, sizeof(flowi6)); 411 412 ipc6.opt = fl->opt; 413 err = ip6_datagram_send_ctl(net, sk, &msg, &flowi6, &ipc6); 414 if (err) 415 goto done; 416 err = -EINVAL; 417 if (fl->opt->opt_flen) 418 goto done; 419 if (fl->opt->opt_nflen == 0) { 420 kfree(fl->opt); 421 fl->opt = NULL; 422 } 423 } 424 425 fl->fl_net = net; 426 fl->expires = jiffies; 427 err = fl6_renew(fl, freq->flr_linger, freq->flr_expires); 428 if (err) 429 goto done; 430 fl->share = freq->flr_share; 431 addr_type = ipv6_addr_type(&freq->flr_dst); 432 if ((addr_type & IPV6_ADDR_MAPPED) || 433 addr_type == IPV6_ADDR_ANY) { 434 err = -EINVAL; 435 goto done; 436 } 437 fl->dst = freq->flr_dst; 438 atomic_set(&fl->users, 1); 439 switch (fl->share) { 440 case IPV6_FL_S_EXCL: 441 case IPV6_FL_S_ANY: 442 break; 443 case IPV6_FL_S_PROCESS: 444 fl->owner.pid = get_task_pid(current, PIDTYPE_PID); 445 break; 446 case IPV6_FL_S_USER: 447 fl->owner.uid = current_euid(); 448 break; 449 default: 450 err = -EINVAL; 451 goto done; 452 } 453 if (fl_shared_exclusive(fl) || fl->opt) { 454 WRITE_ONCE(sock_net(sk)->ipv6.flowlabel_has_excl, 1); 455 static_branch_deferred_inc(&ipv6_flowlabel_exclusive); 456 } 457 return fl; 458 459done: 460 if (fl) { 461 kfree(fl->opt); 462 kfree(fl); 463 } 464 *err_p = err; 465 return NULL; 466} 467 468static int mem_check(struct sock *sk) 469{ 470 struct ipv6_pinfo *np = inet6_sk(sk); 471 struct ipv6_fl_socklist *sfl; 472 int room = FL_MAX_SIZE - atomic_read(&fl_size); 473 int count = 0; 474 475 if (room > FL_MAX_SIZE - FL_MAX_PER_SOCK) 476 return 0; 477 478 rcu_read_lock_bh(); 479 for_each_sk_fl_rcu(np, sfl) 480 count++; 481 rcu_read_unlock_bh(); 482 483 if (room <= 0 || 484 ((count >= FL_MAX_PER_SOCK || 485 (count > 0 && room < FL_MAX_SIZE/2) || room < FL_MAX_SIZE/4) && 486 !capable(CAP_NET_ADMIN))) 487 return -ENOBUFS; 488 489 return 0; 490} 491 492static inline void fl_link(struct ipv6_pinfo *np, struct ipv6_fl_socklist *sfl, 493 struct ip6_flowlabel *fl) 494{ 495 spin_lock_bh(&ip6_sk_fl_lock); 496 sfl->fl = fl; 497 sfl->next = np->ipv6_fl_list; 498 rcu_assign_pointer(np->ipv6_fl_list, sfl); 499 spin_unlock_bh(&ip6_sk_fl_lock); 500} 501 502int ipv6_flowlabel_opt_get(struct sock *sk, struct in6_flowlabel_req *freq, 503 int flags) 504{ 505 struct ipv6_pinfo *np = inet6_sk(sk); 506 struct ipv6_fl_socklist *sfl; 507 508 if (flags & IPV6_FL_F_REMOTE) { 509 freq->flr_label = np->rcv_flowinfo & IPV6_FLOWLABEL_MASK; 510 return 0; 511 } 512 513 if (np->repflow) { 514 freq->flr_label = np->flow_label; 515 return 0; 516 } 517 518 rcu_read_lock_bh(); 519 520 for_each_sk_fl_rcu(np, sfl) { 521 if (sfl->fl->label == (np->flow_label & IPV6_FLOWLABEL_MASK)) { 522 spin_lock_bh(&ip6_fl_lock); 523 freq->flr_label = sfl->fl->label; 524 freq->flr_dst = sfl->fl->dst; 525 freq->flr_share = sfl->fl->share; 526 freq->flr_expires = (sfl->fl->expires - jiffies) / HZ; 527 freq->flr_linger = sfl->fl->linger / HZ; 528 529 spin_unlock_bh(&ip6_fl_lock); 530 rcu_read_unlock_bh(); 531 return 0; 532 } 533 } 534 rcu_read_unlock_bh(); 535 536 return -ENOENT; 537} 538 539#define socklist_dereference(__sflp) \ 540 rcu_dereference_protected(__sflp, lockdep_is_held(&ip6_sk_fl_lock)) 541 542static int ipv6_flowlabel_put(struct sock *sk, struct in6_flowlabel_req *freq) 543{ 544 struct ipv6_pinfo *np = inet6_sk(sk); 545 struct ipv6_fl_socklist __rcu **sflp; 546 struct ipv6_fl_socklist *sfl; 547 548 if (freq->flr_flags & IPV6_FL_F_REFLECT) { 549 if (sk->sk_protocol != IPPROTO_TCP) 550 return -ENOPROTOOPT; 551 if (!np->repflow) 552 return -ESRCH; 553 np->flow_label = 0; 554 np->repflow = 0; 555 return 0; 556 } 557 558 spin_lock_bh(&ip6_sk_fl_lock); 559 for (sflp = &np->ipv6_fl_list; 560 (sfl = socklist_dereference(*sflp)) != NULL; 561 sflp = &sfl->next) { 562 if (sfl->fl->label == freq->flr_label) 563 goto found; 564 } 565 spin_unlock_bh(&ip6_sk_fl_lock); 566 return -ESRCH; 567found: 568 if (freq->flr_label == (np->flow_label & IPV6_FLOWLABEL_MASK)) 569 np->flow_label &= ~IPV6_FLOWLABEL_MASK; 570 *sflp = sfl->next; 571 spin_unlock_bh(&ip6_sk_fl_lock); 572 fl_release(sfl->fl); 573 kfree_rcu(sfl, rcu); 574 return 0; 575} 576 577static int ipv6_flowlabel_renew(struct sock *sk, struct in6_flowlabel_req *freq) 578{ 579 struct ipv6_pinfo *np = inet6_sk(sk); 580 struct net *net = sock_net(sk); 581 struct ipv6_fl_socklist *sfl; 582 int err; 583 584 rcu_read_lock_bh(); 585 for_each_sk_fl_rcu(np, sfl) { 586 if (sfl->fl->label == freq->flr_label) { 587 err = fl6_renew(sfl->fl, freq->flr_linger, 588 freq->flr_expires); 589 rcu_read_unlock_bh(); 590 return err; 591 } 592 } 593 rcu_read_unlock_bh(); 594 595 if (freq->flr_share == IPV6_FL_S_NONE && 596 ns_capable(net->user_ns, CAP_NET_ADMIN)) { 597 struct ip6_flowlabel *fl = fl_lookup(net, freq->flr_label); 598 599 if (fl) { 600 err = fl6_renew(fl, freq->flr_linger, 601 freq->flr_expires); 602 fl_release(fl); 603 return err; 604 } 605 } 606 return -ESRCH; 607} 608 609static int ipv6_flowlabel_get(struct sock *sk, struct in6_flowlabel_req *freq, 610 sockptr_t optval, int optlen) 611{ 612 struct ipv6_fl_socklist *sfl, *sfl1 = NULL; 613 struct ip6_flowlabel *fl, *fl1 = NULL; 614 struct ipv6_pinfo *np = inet6_sk(sk); 615 struct net *net = sock_net(sk); 616 int err; 617 618 if (freq->flr_flags & IPV6_FL_F_REFLECT) { 619 if (net->ipv6.sysctl.flowlabel_consistency) { 620 net_info_ratelimited("Can not set IPV6_FL_F_REFLECT if flowlabel_consistency sysctl is enable\n"); 621 return -EPERM; 622 } 623 624 if (sk->sk_protocol != IPPROTO_TCP) 625 return -ENOPROTOOPT; 626 np->repflow = 1; 627 return 0; 628 } 629 630 if (freq->flr_label & ~IPV6_FLOWLABEL_MASK) 631 return -EINVAL; 632 if (net->ipv6.sysctl.flowlabel_state_ranges && 633 (freq->flr_label & IPV6_FLOWLABEL_STATELESS_FLAG)) 634 return -ERANGE; 635 636 fl = fl_create(net, sk, freq, optval, optlen, &err); 637 if (!fl) 638 return err; 639 640 sfl1 = kmalloc(sizeof(*sfl1), GFP_KERNEL); 641 642 if (freq->flr_label) { 643 err = -EEXIST; 644 rcu_read_lock_bh(); 645 for_each_sk_fl_rcu(np, sfl) { 646 if (sfl->fl->label == freq->flr_label) { 647 if (freq->flr_flags & IPV6_FL_F_EXCL) { 648 rcu_read_unlock_bh(); 649 goto done; 650 } 651 fl1 = sfl->fl; 652 if (!atomic_inc_not_zero(&fl1->users)) 653 fl1 = NULL; 654 break; 655 } 656 } 657 rcu_read_unlock_bh(); 658 659 if (!fl1) 660 fl1 = fl_lookup(net, freq->flr_label); 661 if (fl1) { 662recheck: 663 err = -EEXIST; 664 if (freq->flr_flags&IPV6_FL_F_EXCL) 665 goto release; 666 err = -EPERM; 667 if (fl1->share == IPV6_FL_S_EXCL || 668 fl1->share != fl->share || 669 ((fl1->share == IPV6_FL_S_PROCESS) && 670 (fl1->owner.pid != fl->owner.pid)) || 671 ((fl1->share == IPV6_FL_S_USER) && 672 !uid_eq(fl1->owner.uid, fl->owner.uid))) 673 goto release; 674 675 err = -ENOMEM; 676 if (!sfl1) 677 goto release; 678 if (fl->linger > fl1->linger) 679 fl1->linger = fl->linger; 680 if ((long)(fl->expires - fl1->expires) > 0) 681 fl1->expires = fl->expires; 682 fl_link(np, sfl1, fl1); 683 fl_free(fl); 684 return 0; 685 686release: 687 fl_release(fl1); 688 goto done; 689 } 690 } 691 err = -ENOENT; 692 if (!(freq->flr_flags & IPV6_FL_F_CREATE)) 693 goto done; 694 695 err = -ENOMEM; 696 if (!sfl1) 697 goto done; 698 699 err = mem_check(sk); 700 if (err != 0) 701 goto done; 702 703 fl1 = fl_intern(net, fl, freq->flr_label); 704 if (fl1) 705 goto recheck; 706 707 if (!freq->flr_label) { 708 size_t offset = offsetof(struct in6_flowlabel_req, flr_label); 709 710 if (copy_to_sockptr_offset(optval, offset, &fl->label, 711 sizeof(fl->label))) { 712 /* Intentionally ignore fault. */ 713 } 714 } 715 716 fl_link(np, sfl1, fl); 717 return 0; 718done: 719 fl_free(fl); 720 kfree(sfl1); 721 return err; 722} 723 724int ipv6_flowlabel_opt(struct sock *sk, sockptr_t optval, int optlen) 725{ 726 struct in6_flowlabel_req freq; 727 728 if (optlen < sizeof(freq)) 729 return -EINVAL; 730 if (copy_from_sockptr(&freq, optval, sizeof(freq))) 731 return -EFAULT; 732 733 switch (freq.flr_action) { 734 case IPV6_FL_A_PUT: 735 return ipv6_flowlabel_put(sk, &freq); 736 case IPV6_FL_A_RENEW: 737 return ipv6_flowlabel_renew(sk, &freq); 738 case IPV6_FL_A_GET: 739 return ipv6_flowlabel_get(sk, &freq, optval, optlen); 740 default: 741 return -EINVAL; 742 } 743} 744 745#ifdef CONFIG_PROC_FS 746 747struct ip6fl_iter_state { 748 struct seq_net_private p; 749 struct pid_namespace *pid_ns; 750 int bucket; 751}; 752 753#define ip6fl_seq_private(seq) ((struct ip6fl_iter_state *)(seq)->private) 754 755static struct ip6_flowlabel *ip6fl_get_first(struct seq_file *seq) 756{ 757 struct ip6_flowlabel *fl = NULL; 758 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 759 struct net *net = seq_file_net(seq); 760 761 for (state->bucket = 0; state->bucket <= FL_HASH_MASK; ++state->bucket) { 762 for_each_fl_rcu(state->bucket, fl) { 763 if (net_eq(fl->fl_net, net)) 764 goto out; 765 } 766 } 767 fl = NULL; 768out: 769 return fl; 770} 771 772static struct ip6_flowlabel *ip6fl_get_next(struct seq_file *seq, struct ip6_flowlabel *fl) 773{ 774 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 775 struct net *net = seq_file_net(seq); 776 777 for_each_fl_continue_rcu(fl) { 778 if (net_eq(fl->fl_net, net)) 779 goto out; 780 } 781 782try_again: 783 if (++state->bucket <= FL_HASH_MASK) { 784 for_each_fl_rcu(state->bucket, fl) { 785 if (net_eq(fl->fl_net, net)) 786 goto out; 787 } 788 goto try_again; 789 } 790 fl = NULL; 791 792out: 793 return fl; 794} 795 796static struct ip6_flowlabel *ip6fl_get_idx(struct seq_file *seq, loff_t pos) 797{ 798 struct ip6_flowlabel *fl = ip6fl_get_first(seq); 799 if (fl) 800 while (pos && (fl = ip6fl_get_next(seq, fl)) != NULL) 801 --pos; 802 return pos ? NULL : fl; 803} 804 805static void *ip6fl_seq_start(struct seq_file *seq, loff_t *pos) 806 __acquires(RCU) 807{ 808 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 809 810 state->pid_ns = proc_pid_ns(file_inode(seq->file)->i_sb); 811 812 rcu_read_lock_bh(); 813 return *pos ? ip6fl_get_idx(seq, *pos - 1) : SEQ_START_TOKEN; 814} 815 816static void *ip6fl_seq_next(struct seq_file *seq, void *v, loff_t *pos) 817{ 818 struct ip6_flowlabel *fl; 819 820 if (v == SEQ_START_TOKEN) 821 fl = ip6fl_get_first(seq); 822 else 823 fl = ip6fl_get_next(seq, v); 824 ++*pos; 825 return fl; 826} 827 828static void ip6fl_seq_stop(struct seq_file *seq, void *v) 829 __releases(RCU) 830{ 831 rcu_read_unlock_bh(); 832} 833 834static int ip6fl_seq_show(struct seq_file *seq, void *v) 835{ 836 struct ip6fl_iter_state *state = ip6fl_seq_private(seq); 837 if (v == SEQ_START_TOKEN) { 838 seq_puts(seq, "Label S Owner Users Linger Expires Dst Opt\n"); 839 } else { 840 struct ip6_flowlabel *fl = v; 841 seq_printf(seq, 842 "%05X %-1d %-6d %-6d %-6ld %-8ld %pi6 %-4d\n", 843 (unsigned int)ntohl(fl->label), 844 fl->share, 845 ((fl->share == IPV6_FL_S_PROCESS) ? 846 pid_nr_ns(fl->owner.pid, state->pid_ns) : 847 ((fl->share == IPV6_FL_S_USER) ? 848 from_kuid_munged(seq_user_ns(seq), fl->owner.uid) : 849 0)), 850 atomic_read(&fl->users), 851 fl->linger/HZ, 852 (long)(fl->expires - jiffies)/HZ, 853 &fl->dst, 854 fl->opt ? fl->opt->opt_nflen : 0); 855 } 856 return 0; 857} 858 859static const struct seq_operations ip6fl_seq_ops = { 860 .start = ip6fl_seq_start, 861 .next = ip6fl_seq_next, 862 .stop = ip6fl_seq_stop, 863 .show = ip6fl_seq_show, 864}; 865 866static int __net_init ip6_flowlabel_proc_init(struct net *net) 867{ 868 if (!proc_create_net("ip6_flowlabel", 0444, net->proc_net, 869 &ip6fl_seq_ops, sizeof(struct ip6fl_iter_state))) 870 return -ENOMEM; 871 return 0; 872} 873 874static void __net_exit ip6_flowlabel_proc_fini(struct net *net) 875{ 876 remove_proc_entry("ip6_flowlabel", net->proc_net); 877} 878#else 879static inline int ip6_flowlabel_proc_init(struct net *net) 880{ 881 return 0; 882} 883static inline void ip6_flowlabel_proc_fini(struct net *net) 884{ 885} 886#endif 887 888static void __net_exit ip6_flowlabel_net_exit(struct net *net) 889{ 890 ip6_fl_purge(net); 891 ip6_flowlabel_proc_fini(net); 892} 893 894static struct pernet_operations ip6_flowlabel_net_ops = { 895 .init = ip6_flowlabel_proc_init, 896 .exit = ip6_flowlabel_net_exit, 897}; 898 899int ip6_flowlabel_init(void) 900{ 901 return register_pernet_subsys(&ip6_flowlabel_net_ops); 902} 903 904void ip6_flowlabel_cleanup(void) 905{ 906 static_key_deferred_flush(&ipv6_flowlabel_exclusive); 907 del_timer(&ip6_fl_gc_timer); 908 unregister_pernet_subsys(&ip6_flowlabel_net_ops); 909} 910