sctp/sysctl.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* SCTP kernel implementation
   3  * (C) Copyright IBM Corp. 2002, 2004
   4  * Copyright (c) 2002 Intel Corp.
   5  *
   6  * This file is part of the SCTP kernel implementation
   7  *
   8  * Sysctl related interfaces for SCTP.
   9  *
  10  * Please send any bug reports or fixes you make to the
  11  * email address(es):
  12  *    lksctp developers <linux-sctp@vger.kernel.org>
  13  *
  14  * Written or modified by:
  15  *    Mingqin Liu           <liuming@us.ibm.com>
  16  *    Jon Grimm             <jgrimm@us.ibm.com>
  17  *    Ardelle Fan           <ardelle.fan@intel.com>
  18  *    Ryan Layer            <rmlayer@us.ibm.com>
  19  *    Sridhar Samudrala     <sri@us.ibm.com>
  20  */
  21
  22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  23
  24 #include <net/sctp/structs.h>
  25 #include <net/sctp/sctp.h>
  26 #include <linux/sysctl.h>
  27
  28 static int timer_max = 86400000; /* ms in one day */
  29 static int sack_timer_min = 1;
  30 static int sack_timer_max = 500;
  31 static int addr_scope_max = SCTP_SCOPE_POLICY_MAX;
  32 static int rwnd_scale_max = 16;
  33 static int rto_alpha_min = 0;
  34 static int rto_beta_min = 0;
  35 static int rto_alpha_max = 1000;
  36 static int rto_beta_max = 1000;
  37 static int pf_expose_max = SCTP_PF_EXPOSE_MAX;
  38 static int ps_retrans_max = SCTP_PS_RETRANS_MAX;
  39 static int udp_port_max = 65535;
  40
  41 static unsigned long max_autoclose_min = 0;
  42 static unsigned long max_autoclose_max =
  43         (MAX_SCHEDULE_TIMEOUT / HZ > UINT_MAX)
  44         ? UINT_MAX : MAX_SCHEDULE_TIMEOUT / HZ;
  45
  46 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
  47                                  void *buffer, size_t *lenp, loff_t *ppos);
  48 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
  49                                 void *buffer, size_t *lenp, loff_t *ppos);
  50 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write, void *buffer,
  51                                 size_t *lenp, loff_t *ppos);
  52 static int proc_sctp_do_udp_port(struct ctl_table *ctl, int write, void *buffer,
  53                                  size_t *lenp, loff_t *ppos);
  54 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
  55                                    void *buffer, size_t *lenp, loff_t *ppos);
  56 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
  57                              void *buffer, size_t *lenp, loff_t *ppos);
  58 static int proc_sctp_do_probe_interval(struct ctl_table *ctl, int write,
  59                                        void *buffer, size_t *lenp, loff_t *ppos);
  60
  61 static struct ctl_table sctp_table[] = {
  62         {
  63                 .procname       = "sctp_mem",
  64                 .data           = &sysctl_sctp_mem,
  65                 .maxlen         = sizeof(sysctl_sctp_mem),
  66                 .mode           = 0644,
  67                 .proc_handler   = proc_doulongvec_minmax
  68         },
  69         {
  70                 .procname       = "sctp_rmem",
  71                 .data           = &sysctl_sctp_rmem,
  72                 .maxlen         = sizeof(sysctl_sctp_rmem),
  73                 .mode           = 0644,
  74                 .proc_handler   = proc_dointvec,
  75         },
  76         {
  77                 .procname       = "sctp_wmem",
  78                 .data           = &sysctl_sctp_wmem,
  79                 .maxlen         = sizeof(sysctl_sctp_wmem),
  80                 .mode           = 0644,
  81                 .proc_handler   = proc_dointvec,
  82         },
  83
  84         { /* sentinel */ }
  85 };
  86
  87 /* The following index defines are used in sctp_sysctl_net_register().
  88  * If you add new items to the sctp_net_table, please ensure that
  89  * the index values of these defines hold the same meaning indicated by
  90  * their macro names when they appear in sctp_net_table.
  91  */
  92 #define SCTP_RTO_MIN_IDX       0
  93 #define SCTP_RTO_MAX_IDX       1
  94 #define SCTP_PF_RETRANS_IDX    2
  95 #define SCTP_PS_RETRANS_IDX    3
  96
  97 static struct ctl_table sctp_net_table[] = {
  98         [SCTP_RTO_MIN_IDX] = {
  99                 .procname       = "rto_min",
 100                 .data           = &init_net.sctp.rto_min,
 101                 .maxlen         = sizeof(unsigned int),
 102                 .mode           = 0644,
 103                 .proc_handler   = proc_sctp_do_rto_min,
 104                 .extra1         = SYSCTL_ONE,
 105                 .extra2         = &init_net.sctp.rto_max
 106         },
 107         [SCTP_RTO_MAX_IDX] =  {
 108                 .procname       = "rto_max",
 109                 .data           = &init_net.sctp.rto_max,
 110                 .maxlen         = sizeof(unsigned int),
 111                 .mode           = 0644,
 112                 .proc_handler   = proc_sctp_do_rto_max,
 113                 .extra1         = &init_net.sctp.rto_min,
 114                 .extra2         = &timer_max
 115         },
 116         [SCTP_PF_RETRANS_IDX] = {
 117                 .procname       = "pf_retrans",
 118                 .data           = &init_net.sctp.pf_retrans,
 119                 .maxlen         = sizeof(int),
 120                 .mode           = 0644,
 121                 .proc_handler   = proc_dointvec_minmax,
 122                 .extra1         = SYSCTL_ZERO,
 123                 .extra2         = &init_net.sctp.ps_retrans,
 124         },
 125         [SCTP_PS_RETRANS_IDX] = {
 126                 .procname       = "ps_retrans",
 127                 .data           = &init_net.sctp.ps_retrans,
 128                 .maxlen         = sizeof(int),
 129                 .mode           = 0644,
 130                 .proc_handler   = proc_dointvec_minmax,
 131                 .extra1         = &init_net.sctp.pf_retrans,
 132                 .extra2         = &ps_retrans_max,
 133         },
 134         {
 135                 .procname       = "rto_initial",
 136                 .data           = &init_net.sctp.rto_initial,
 137                 .maxlen         = sizeof(unsigned int),
 138                 .mode           = 0644,
 139                 .proc_handler   = proc_dointvec_minmax,
 140                 .extra1         = SYSCTL_ONE,
 141                 .extra2         = &timer_max
 142         },
 143         {
 144                 .procname       = "rto_alpha_exp_divisor",
 145                 .data           = &init_net.sctp.rto_alpha,
 146                 .maxlen         = sizeof(int),
 147                 .mode           = 0644,
 148                 .proc_handler   = proc_sctp_do_alpha_beta,
 149                 .extra1         = &rto_alpha_min,
 150                 .extra2         = &rto_alpha_max,
 151         },
 152         {
 153                 .procname       = "rto_beta_exp_divisor",
 154                 .data           = &init_net.sctp.rto_beta,
 155                 .maxlen         = sizeof(int),
 156                 .mode           = 0644,
 157                 .proc_handler   = proc_sctp_do_alpha_beta,
 158                 .extra1         = &rto_beta_min,
 159                 .extra2         = &rto_beta_max,
 160         },
 161         {
 162                 .procname       = "max_burst",
 163                 .data           = &init_net.sctp.max_burst,
 164                 .maxlen         = sizeof(int),
 165                 .mode           = 0644,
 166                 .proc_handler   = proc_dointvec_minmax,
 167                 .extra1         = SYSCTL_ZERO,
 168                 .extra2         = SYSCTL_INT_MAX,
 169         },
 170         {
 171                 .procname       = "cookie_preserve_enable",
 172                 .data           = &init_net.sctp.cookie_preserve_enable,
 173                 .maxlen         = sizeof(int),
 174                 .mode           = 0644,
 175                 .proc_handler   = proc_dointvec,
 176         },
 177         {
 178                 .procname       = "cookie_hmac_alg",
 179                 .data           = &init_net.sctp.sctp_hmac_alg,
 180                 .maxlen         = 8,
 181                 .mode           = 0644,
 182                 .proc_handler   = proc_sctp_do_hmac_alg,
 183         },
 184         {
 185                 .procname       = "valid_cookie_life",
 186                 .data           = &init_net.sctp.valid_cookie_life,
 187                 .maxlen         = sizeof(unsigned int),
 188                 .mode           = 0644,
 189                 .proc_handler   = proc_dointvec_minmax,
 190                 .extra1         = SYSCTL_ONE,
 191                 .extra2         = &timer_max
 192         },
 193         {
 194                 .procname       = "sack_timeout",
 195                 .data           = &init_net.sctp.sack_timeout,
 196                 .maxlen         = sizeof(int),
 197                 .mode           = 0644,
 198                 .proc_handler   = proc_dointvec_minmax,
 199                 .extra1         = &sack_timer_min,
 200                 .extra2         = &sack_timer_max,
 201         },
 202         {
 203                 .procname       = "hb_interval",
 204                 .data           = &init_net.sctp.hb_interval,
 205                 .maxlen         = sizeof(unsigned int),
 206                 .mode           = 0644,
 207                 .proc_handler   = proc_dointvec_minmax,
 208                 .extra1         = SYSCTL_ONE,
 209                 .extra2         = &timer_max
 210         },
 211         {
 212                 .procname       = "association_max_retrans",
 213                 .data           = &init_net.sctp.max_retrans_association,
 214                 .maxlen         = sizeof(int),
 215                 .mode           = 0644,
 216                 .proc_handler   = proc_dointvec_minmax,
 217                 .extra1         = SYSCTL_ONE,
 218                 .extra2         = SYSCTL_INT_MAX,
 219         },
 220         {
 221                 .procname       = "path_max_retrans",
 222                 .data           = &init_net.sctp.max_retrans_path,
 223                 .maxlen         = sizeof(int),
 224                 .mode           = 0644,
 225                 .proc_handler   = proc_dointvec_minmax,
 226                 .extra1         = SYSCTL_ONE,
 227                 .extra2         = SYSCTL_INT_MAX,
 228         },
 229         {
 230                 .procname       = "max_init_retransmits",
 231                 .data           = &init_net.sctp.max_retrans_init,
 232                 .maxlen         = sizeof(int),
 233                 .mode           = 0644,
 234                 .proc_handler   = proc_dointvec_minmax,
 235                 .extra1         = SYSCTL_ONE,
 236                 .extra2         = SYSCTL_INT_MAX,
 237         },
 238         {
 239                 .procname       = "sndbuf_policy",
 240                 .data           = &init_net.sctp.sndbuf_policy,
 241                 .maxlen         = sizeof(int),
 242                 .mode           = 0644,
 243                 .proc_handler   = proc_dointvec,
 244         },
 245         {
 246                 .procname       = "rcvbuf_policy",
 247                 .data           = &init_net.sctp.rcvbuf_policy,
 248                 .maxlen         = sizeof(int),
 249                 .mode           = 0644,
 250                 .proc_handler   = proc_dointvec,
 251         },
 252         {
 253                 .procname       = "default_auto_asconf",
 254                 .data           = &init_net.sctp.default_auto_asconf,
 255                 .maxlen         = sizeof(int),
 256                 .mode           = 0644,
 257                 .proc_handler   = proc_dointvec,
 258         },
 259         {
 260                 .procname       = "addip_enable",
 261                 .data           = &init_net.sctp.addip_enable,
 262                 .maxlen         = sizeof(int),
 263                 .mode           = 0644,
 264                 .proc_handler   = proc_dointvec,
 265         },
 266         {
 267                 .procname       = "addip_noauth_enable",
 268                 .data           = &init_net.sctp.addip_noauth,
 269                 .maxlen         = sizeof(int),
 270                 .mode           = 0644,
 271                 .proc_handler   = proc_dointvec,
 272         },
 273         {
 274                 .procname       = "prsctp_enable",
 275                 .data           = &init_net.sctp.prsctp_enable,
 276                 .maxlen         = sizeof(int),
 277                 .mode           = 0644,
 278                 .proc_handler   = proc_dointvec,
 279         },
 280         {
 281                 .procname       = "reconf_enable",
 282                 .data           = &init_net.sctp.reconf_enable,
 283                 .maxlen         = sizeof(int),
 284                 .mode           = 0644,
 285                 .proc_handler   = proc_dointvec,
 286         },
 287         {
 288                 .procname       = "auth_enable",
 289                 .data           = &init_net.sctp.auth_enable,
 290                 .maxlen         = sizeof(int),
 291                 .mode           = 0644,
 292                 .proc_handler   = proc_sctp_do_auth,
 293         },
 294         {
 295                 .procname       = "intl_enable",
 296                 .data           = &init_net.sctp.intl_enable,
 297                 .maxlen         = sizeof(int),
 298                 .mode           = 0644,
 299                 .proc_handler   = proc_dointvec,
 300         },
 301         {
 302                 .procname       = "ecn_enable",
 303                 .data           = &init_net.sctp.ecn_enable,
 304                 .maxlen         = sizeof(int),
 305                 .mode           = 0644,
 306                 .proc_handler   = proc_dointvec,
 307         },
 308         {
 309                 .procname       = "plpmtud_probe_interval",
 310                 .data           = &init_net.sctp.probe_interval,
 311                 .maxlen         = sizeof(int),
 312                 .mode           = 0644,
 313                 .proc_handler   = proc_sctp_do_probe_interval,
 314         },
 315         {
 316                 .procname       = "udp_port",
 317                 .data           = &init_net.sctp.udp_port,
 318                 .maxlen         = sizeof(int),
 319                 .mode           = 0644,
 320                 .proc_handler   = proc_sctp_do_udp_port,
 321                 .extra1         = SYSCTL_ZERO,
 322                 .extra2         = &udp_port_max,
 323         },
 324         {
 325                 .procname       = "encap_port",
 326                 .data           = &init_net.sctp.encap_port,
 327                 .maxlen         = sizeof(int),
 328                 .mode           = 0644,
 329                 .proc_handler   = proc_dointvec_minmax,
 330                 .extra1         = SYSCTL_ZERO,
 331                 .extra2         = &udp_port_max,
 332         },
 333         {
 334                 .procname       = "addr_scope_policy",
 335                 .data           = &init_net.sctp.scope_policy,
 336                 .maxlen         = sizeof(int),
 337                 .mode           = 0644,
 338                 .proc_handler   = proc_dointvec_minmax,
 339                 .extra1         = SYSCTL_ZERO,
 340                 .extra2         = &addr_scope_max,
 341         },
 342         {
 343                 .procname       = "rwnd_update_shift",
 344                 .data           = &init_net.sctp.rwnd_upd_shift,
 345                 .maxlen         = sizeof(int),
 346                 .mode           = 0644,
 347                 .proc_handler   = &proc_dointvec_minmax,
 348                 .extra1         = SYSCTL_ONE,
 349                 .extra2         = &rwnd_scale_max,
 350         },
 351         {
 352                 .procname       = "max_autoclose",
 353                 .data           = &init_net.sctp.max_autoclose,
 354                 .maxlen         = sizeof(unsigned long),
 355                 .mode           = 0644,
 356                 .proc_handler   = &proc_doulongvec_minmax,
 357                 .extra1         = &max_autoclose_min,
 358                 .extra2         = &max_autoclose_max,
 359         },
 360         {
 361                 .procname       = "pf_enable",
 362                 .data           = &init_net.sctp.pf_enable,
 363                 .maxlen         = sizeof(int),
 364                 .mode           = 0644,
 365                 .proc_handler   = proc_dointvec,
 366         },
 367         {
 368                 .procname       = "pf_expose",
 369                 .data           = &init_net.sctp.pf_expose,
 370                 .maxlen         = sizeof(int),
 371                 .mode           = 0644,
 372                 .proc_handler   = proc_dointvec_minmax,
 373                 .extra1         = SYSCTL_ZERO,
 374                 .extra2         = &pf_expose_max,
 375         },
 376
 377         { /* sentinel */ }
 378 };
 379
 380 static int proc_sctp_do_hmac_alg(struct ctl_table *ctl, int write,
 381                                  void *buffer, size_t *lenp, loff_t *ppos)
 382 {
 383         struct net *net = current->nsproxy->net_ns;
 384         struct ctl_table tbl;
 385         bool changed = false;
 386         char *none = "none";
 387         char tmp[8] = {0};
 388         int ret;
 389
 390         memset(&tbl, 0, sizeof(struct ctl_table));
 391
 392         if (write) {
 393                 tbl.data = tmp;
 394                 tbl.maxlen = sizeof(tmp);
 395         } else {
 396                 tbl.data = net->sctp.sctp_hmac_alg ? : none;
 397                 tbl.maxlen = strlen(tbl.data);
 398         }
 399
 400         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 401         if (write && ret == 0) {
 402 #ifdef CONFIG_CRYPTO_MD5
 403                 if (!strncmp(tmp, "md5", 3)) {
 404                         net->sctp.sctp_hmac_alg = "md5";
 405                         changed = true;
 406                 }
 407 #endif
 408 #ifdef CONFIG_CRYPTO_SHA1
 409                 if (!strncmp(tmp, "sha1", 4)) {
 410                         net->sctp.sctp_hmac_alg = "sha1";
 411                         changed = true;
 412                 }
 413 #endif
 414                 if (!strncmp(tmp, "none", 4)) {
 415                         net->sctp.sctp_hmac_alg = NULL;
 416                         changed = true;
 417                 }
 418                 if (!changed)
 419                         ret = -EINVAL;
 420         }
 421
 422         return ret;
 423 }
 424
 425 static int proc_sctp_do_rto_min(struct ctl_table *ctl, int write,
 426                                 void *buffer, size_t *lenp, loff_t *ppos)
 427 {
 428         struct net *net = current->nsproxy->net_ns;
 429         unsigned int min = *(unsigned int *) ctl->extra1;
 430         unsigned int max = *(unsigned int *) ctl->extra2;
 431         struct ctl_table tbl;
 432         int ret, new_value;
 433
 434         memset(&tbl, 0, sizeof(struct ctl_table));
 435         tbl.maxlen = sizeof(unsigned int);
 436
 437         if (write)
 438                 tbl.data = &new_value;
 439         else
 440                 tbl.data = &net->sctp.rto_min;
 441
 442         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 443         if (write && ret == 0) {
 444                 if (new_value > max || new_value < min)
 445                         return -EINVAL;
 446
 447                 net->sctp.rto_min = new_value;
 448         }
 449
 450         return ret;
 451 }
 452
 453 static int proc_sctp_do_rto_max(struct ctl_table *ctl, int write,
 454                                 void *buffer, size_t *lenp, loff_t *ppos)
 455 {
 456         struct net *net = current->nsproxy->net_ns;
 457         unsigned int min = *(unsigned int *) ctl->extra1;
 458         unsigned int max = *(unsigned int *) ctl->extra2;
 459         struct ctl_table tbl;
 460         int ret, new_value;
 461
 462         memset(&tbl, 0, sizeof(struct ctl_table));
 463         tbl.maxlen = sizeof(unsigned int);
 464
 465         if (write)
 466                 tbl.data = &new_value;
 467         else
 468                 tbl.data = &net->sctp.rto_max;
 469
 470         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 471         if (write && ret == 0) {
 472                 if (new_value > max || new_value < min)
 473                         return -EINVAL;
 474
 475                 net->sctp.rto_max = new_value;
 476         }
 477
 478         return ret;
 479 }
 480
 481 static int proc_sctp_do_alpha_beta(struct ctl_table *ctl, int write,
 482                                    void *buffer, size_t *lenp, loff_t *ppos)
 483 {
 484         if (write)
 485                 pr_warn_once("Changing rto_alpha or rto_beta may lead to "
 486                              "suboptimal rtt/srtt estimations!\n");
 487
 488         return proc_dointvec_minmax(ctl, write, buffer, lenp, ppos);
 489 }
 490
 491 static int proc_sctp_do_auth(struct ctl_table *ctl, int write,
 492                              void *buffer, size_t *lenp, loff_t *ppos)
 493 {
 494         struct net *net = current->nsproxy->net_ns;
 495         struct ctl_table tbl;
 496         int new_value, ret;
 497
 498         memset(&tbl, 0, sizeof(struct ctl_table));
 499         tbl.maxlen = sizeof(unsigned int);
 500
 501         if (write)
 502                 tbl.data = &new_value;
 503         else
 504                 tbl.data = &net->sctp.auth_enable;
 505
 506         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 507         if (write && ret == 0) {
 508                 struct sock *sk = net->sctp.ctl_sock;
 509
 510                 net->sctp.auth_enable = new_value;
 511                 /* Update the value in the control socket */
 512                 lock_sock(sk);
 513                 sctp_sk(sk)->ep->auth_enable = new_value;
 514                 release_sock(sk);
 515         }
 516
 517         return ret;
 518 }
 519
 520 static int proc_sctp_do_udp_port(struct ctl_table *ctl, int write,
 521                                  void *buffer, size_t *lenp, loff_t *ppos)
 522 {
 523         struct net *net = current->nsproxy->net_ns;
 524         unsigned int min = *(unsigned int *)ctl->extra1;
 525         unsigned int max = *(unsigned int *)ctl->extra2;
 526         struct ctl_table tbl;
 527         int ret, new_value;
 528
 529         memset(&tbl, 0, sizeof(struct ctl_table));
 530         tbl.maxlen = sizeof(unsigned int);
 531
 532         if (write)
 533                 tbl.data = &new_value;
 534         else
 535                 tbl.data = &net->sctp.udp_port;
 536
 537         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 538         if (write && ret == 0) {
 539                 struct sock *sk = net->sctp.ctl_sock;
 540
 541                 if (new_value > max || new_value < min)
 542                         return -EINVAL;
 543
 544                 net->sctp.udp_port = new_value;
 545                 sctp_udp_sock_stop(net);
 546                 if (new_value) {
 547                         ret = sctp_udp_sock_start(net);
 548                         if (ret)
 549                                 net->sctp.udp_port = 0;
 550                 }
 551
 552                 /* Update the value in the control socket */
 553                 lock_sock(sk);
 554                 sctp_sk(sk)->udp_port = htons(net->sctp.udp_port);
 555                 release_sock(sk);
 556         }
 557
 558         return ret;
 559 }
 560
 561 static int proc_sctp_do_probe_interval(struct ctl_table *ctl, int write,
 562                                        void *buffer, size_t *lenp, loff_t *ppos)
 563 {
 564         struct net *net = current->nsproxy->net_ns;
 565         struct ctl_table tbl;
 566         int ret, new_value;
 567
 568         memset(&tbl, 0, sizeof(struct ctl_table));
 569         tbl.maxlen = sizeof(unsigned int);
 570
 571         if (write)
 572                 tbl.data = &new_value;
 573         else
 574                 tbl.data = &net->sctp.probe_interval;
 575
 576         ret = proc_dointvec(&tbl, write, buffer, lenp, ppos);
 577         if (write && ret == 0) {
 578                 if (new_value && new_value < SCTP_PROBE_TIMER_MIN)
 579                         return -EINVAL;
 580
 581                 net->sctp.probe_interval = new_value;
 582         }
 583
 584         return ret;
 585 }
 586
 587 int sctp_sysctl_net_register(struct net *net)
 588 {
 589         struct ctl_table *table;
 590         int i;
 591
 592         table = kmemdup(sctp_net_table, sizeof(sctp_net_table), GFP_KERNEL);
 593         if (!table)
 594                 return -ENOMEM;
 595
 596         for (i = 0; table[i].data; i++)
 597                 table[i].data += (char *)(&net->sctp) - (char *)&init_net.sctp;
 598
 599         table[SCTP_RTO_MIN_IDX].extra2 = &net->sctp.rto_max;
 600         table[SCTP_RTO_MAX_IDX].extra1 = &net->sctp.rto_min;
 601         table[SCTP_PF_RETRANS_IDX].extra2 = &net->sctp.ps_retrans;
 602         table[SCTP_PS_RETRANS_IDX].extra1 = &net->sctp.pf_retrans;
 603
 604         net->sctp.sysctl_header = register_net_sysctl(net, "net/sctp", table);
 605         if (net->sctp.sysctl_header == NULL) {
 606                 kfree(table);
 607                 return -ENOMEM;
 608         }
 609         return 0;
 610 }
 611
 612 void sctp_sysctl_net_unregister(struct net *net)
 613 {
 614         struct ctl_table *table;
 615
 616         table = net->sctp.sysctl_header->ctl_table_arg;
 617         unregister_net_sysctl_table(net->sctp.sysctl_header);
 618         kfree(table);
 619 }
 620
 621 static struct ctl_table_header *sctp_sysctl_header;
 622
 623 /* Sysctl registration.  */
 624 void sctp_sysctl_register(void)
 625 {
 626         sctp_sysctl_header = register_net_sysctl(&init_net, "net/sctp", sctp_table);
 627 }
 628
 629 /* Sysctl deregistration.  */
 630 void sctp_sysctl_unregister(void)
 631 {
 632         unregister_net_sysctl_table(sctp_sysctl_header);
 633 }