net/ipv4/sysctl_net_ipv4.c

   1 /*
   2  * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
   3  *
   4  * Begun April 1, 1996, Mike Shaver.
   5  * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
   6  */
   7
   8 #include <linux/mm.h>
   9 #include <linux/module.h>
  10 #include <linux/sysctl.h>
  11 #include <linux/igmp.h>
  12 #include <linux/inetdevice.h>
  13 #include <linux/seqlock.h>
  14 #include <linux/init.h>
  15 #include <linux/slab.h>
  16 #include <linux/nsproxy.h>
  17 #include <net/snmp.h>
  18 #include <net/icmp.h>
  19 #include <net/ip.h>
  20 #include <net/route.h>
  21 #include <net/tcp.h>
  22 #include <net/udp.h>
  23 #include <net/cipso_ipv4.h>
  24 #include <net/inet_frag.h>
  25 #include <net/ping.h>
  26
  27 static int zero;
  28 static int tcp_retr1_max = 255;
  29 static int ip_local_port_range_min[] = { 1, 1 };
  30 static int ip_local_port_range_max[] = { 65535, 65535 };
  31 static int tcp_adv_win_scale_min = -31;
  32 static int tcp_adv_win_scale_max = 31;
  33 static int ip_ttl_min = 1;
  34 static int ip_ttl_max = 255;
  35 static int tcp_syn_retries_min = 1;
  36 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
  37 static int ip_ping_group_range_min[] = { 0, 0 };
  38 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
  39
  40 /* Update system visible IP port range */
  41 static void set_local_port_range(int range[2])
  42 {
  43         write_seqlock(&sysctl_local_ports.lock);
  44         sysctl_local_ports.range[0] = range[0];
  45         sysctl_local_ports.range[1] = range[1];
  46         write_sequnlock(&sysctl_local_ports.lock);
  47 }
  48
  49 /* Validate changes from /proc interface. */
  50 static int ipv4_local_port_range(ctl_table *table, int write,
  51                                  void __user *buffer,
  52                                  size_t *lenp, loff_t *ppos)
  53 {
  54         int ret;
  55         int range[2];
  56         ctl_table tmp = {
  57                 .data = &range,
  58                 .maxlen = sizeof(range),
  59                 .mode = table->mode,
  60                 .extra1 = &ip_local_port_range_min,
  61                 .extra2 = &ip_local_port_range_max,
  62         };
  63
  64         inet_get_local_port_range(range, range + 1);
  65         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
  66
  67         if (write && ret == 0) {
  68                 if (range[1] < range[0])
  69                         ret = -EINVAL;
  70                 else
  71                         set_local_port_range(range);
  72         }
  73
  74         return ret;
  75 }
  76
  77
  78 void inet_get_ping_group_range_table(struct ctl_table *table, gid_t *low, gid_t *high)
  79 {
  80         gid_t *data = table->data;
  81         unsigned seq;
  82         do {
  83                 seq = read_seqbegin(&sysctl_local_ports.lock);
  84
  85                 *low = data[0];
  86                 *high = data[1];
  87         } while (read_seqretry(&sysctl_local_ports.lock, seq));
  88 }
  89
  90 /* Update system visible IP port range */
  91 static void set_ping_group_range(struct ctl_table *table, int range[2])
  92 {
  93         gid_t *data = table->data;
  94         write_seqlock(&sysctl_local_ports.lock);
  95         data[0] = range[0];
  96         data[1] = range[1];
  97         write_sequnlock(&sysctl_local_ports.lock);
  98 }
  99
 100 /* Validate changes from /proc interface. */
 101 static int ipv4_ping_group_range(ctl_table *table, int write,
 102                                  void __user *buffer,
 103                                  size_t *lenp, loff_t *ppos)
 104 {
 105         int ret;
 106         gid_t range[2];
 107         ctl_table tmp = {
 108                 .data = &range,
 109                 .maxlen = sizeof(range),
 110                 .mode = table->mode,
 111                 .extra1 = &ip_ping_group_range_min,
 112                 .extra2 = &ip_ping_group_range_max,
 113         };
 114
 115         inet_get_ping_group_range_table(table, range, range + 1);
 116         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 117
 118         if (write && ret == 0)
 119                 set_ping_group_range(table, range);
 120
 121         return ret;
 122 }
 123
 124 static int proc_tcp_congestion_control(ctl_table *ctl, int write,
 125                                        void __user *buffer, size_t *lenp, loff_t *ppos)
 126 {
 127         char val[TCP_CA_NAME_MAX];
 128         ctl_table tbl = {
 129                 .data = val,
 130                 .maxlen = TCP_CA_NAME_MAX,
 131         };
 132         int ret;
 133
 134         tcp_get_default_congestion_control(val);
 135
 136         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 137         if (write && ret == 0)
 138                 ret = tcp_set_default_congestion_control(val);
 139         return ret;
 140 }
 141
 142 static int proc_tcp_available_congestion_control(ctl_table *ctl,
 143                                                  int write,
 144                                                  void __user *buffer, size_t *lenp,
 145                                                  loff_t *ppos)
 146 {
 147         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
 148         int ret;
 149
 150         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 151         if (!tbl.data)
 152                 return -ENOMEM;
 153         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
 154         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 155         kfree(tbl.data);
 156         return ret;
 157 }
 158
 159 static int proc_allowed_congestion_control(ctl_table *ctl,
 160                                            int write,
 161                                            void __user *buffer, size_t *lenp,
 162                                            loff_t *ppos)
 163 {
 164         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 165         int ret;
 166
 167         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 168         if (!tbl.data)
 169                 return -ENOMEM;
 170
 171         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
 172         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 173         if (write && ret == 0)
 174                 ret = tcp_set_allowed_congestion_control(tbl.data);
 175         kfree(tbl.data);
 176         return ret;
 177 }
 178
 179 static struct ctl_table ipv4_table[] = {
 180         {
 181                 .procname       = "tcp_timestamps",
 182                 .data           = &sysctl_tcp_timestamps,
 183                 .maxlen         = sizeof(int),
 184                 .mode           = 0644,
 185                 .proc_handler   = proc_dointvec
 186         },
 187         {
 188                 .procname       = "tcp_window_scaling",
 189                 .data           = &sysctl_tcp_window_scaling,
 190                 .maxlen         = sizeof(int),
 191                 .mode           = 0644,
 192                 .proc_handler   = proc_dointvec
 193         },
 194         {
 195                 .procname       = "tcp_sack",
 196                 .data           = &sysctl_tcp_sack,
 197                 .maxlen         = sizeof(int),
 198                 .mode           = 0644,
 199                 .proc_handler   = proc_dointvec
 200         },
 201         {
 202                 .procname       = "tcp_retrans_collapse",
 203                 .data           = &sysctl_tcp_retrans_collapse,
 204                 .maxlen         = sizeof(int),
 205                 .mode           = 0644,
 206                 .proc_handler   = proc_dointvec
 207         },
 208         {
 209                 .procname       = "ip_default_ttl",
 210                 .data           = &sysctl_ip_default_ttl,
 211                 .maxlen         = sizeof(int),
 212                 .mode           = 0644,
 213                 .proc_handler   = proc_dointvec_minmax,
 214                 .extra1         = &ip_ttl_min,
 215                 .extra2         = &ip_ttl_max,
 216         },
 217         {
 218                 .procname       = "ip_no_pmtu_disc",
 219                 .data           = &ipv4_config.no_pmtu_disc,
 220                 .maxlen         = sizeof(int),
 221                 .mode           = 0644,
 222                 .proc_handler   = proc_dointvec
 223         },
 224         {
 225                 .procname       = "ip_nonlocal_bind",
 226                 .data           = &sysctl_ip_nonlocal_bind,
 227                 .maxlen         = sizeof(int),
 228                 .mode           = 0644,
 229                 .proc_handler   = proc_dointvec
 230         },
 231         {
 232                 .procname       = "tcp_syn_retries",
 233                 .data           = &sysctl_tcp_syn_retries,
 234                 .maxlen         = sizeof(int),
 235                 .mode           = 0644,
 236                 .proc_handler   = proc_dointvec_minmax,
 237                 .extra1         = &tcp_syn_retries_min,
 238                 .extra2         = &tcp_syn_retries_max
 239         },
 240         {
 241                 .procname       = "tcp_synack_retries",
 242                 .data           = &sysctl_tcp_synack_retries,
 243                 .maxlen         = sizeof(int),
 244                 .mode           = 0644,
 245                 .proc_handler   = proc_dointvec
 246         },
 247         {
 248                 .procname       = "tcp_max_orphans",
 249                 .data           = &sysctl_tcp_max_orphans,
 250                 .maxlen         = sizeof(int),
 251                 .mode           = 0644,
 252                 .proc_handler   = proc_dointvec
 253         },
 254         {
 255                 .procname       = "tcp_max_tw_buckets",
 256                 .data           = &tcp_death_row.sysctl_max_tw_buckets,
 257                 .maxlen         = sizeof(int),
 258                 .mode           = 0644,
 259                 .proc_handler   = proc_dointvec
 260         },
 261         {
 262                 .procname       = "ip_dynaddr",
 263                 .data           = &sysctl_ip_dynaddr,
 264                 .maxlen         = sizeof(int),
 265                 .mode           = 0644,
 266                 .proc_handler   = proc_dointvec
 267         },
 268         {
 269                 .procname       = "tcp_keepalive_time",
 270                 .data           = &sysctl_tcp_keepalive_time,
 271                 .maxlen         = sizeof(int),
 272                 .mode           = 0644,
 273                 .proc_handler   = proc_dointvec_jiffies,
 274         },
 275         {
 276                 .procname       = "tcp_keepalive_probes",
 277                 .data           = &sysctl_tcp_keepalive_probes,
 278                 .maxlen         = sizeof(int),
 279                 .mode           = 0644,
 280                 .proc_handler   = proc_dointvec
 281         },
 282         {
 283                 .procname       = "tcp_keepalive_intvl",
 284                 .data           = &sysctl_tcp_keepalive_intvl,
 285                 .maxlen         = sizeof(int),
 286                 .mode           = 0644,
 287                 .proc_handler   = proc_dointvec_jiffies,
 288         },
 289         {
 290                 .procname       = "tcp_retries1",
 291                 .data           = &sysctl_tcp_retries1,
 292                 .maxlen         = sizeof(int),
 293                 .mode           = 0644,
 294                 .proc_handler   = proc_dointvec_minmax,
 295                 .extra2         = &tcp_retr1_max
 296         },
 297         {
 298                 .procname       = "tcp_retries2",
 299                 .data           = &sysctl_tcp_retries2,
 300                 .maxlen         = sizeof(int),
 301                 .mode           = 0644,
 302                 .proc_handler   = proc_dointvec
 303         },
 304         {
 305                 .procname       = "tcp_fin_timeout",
 306                 .data           = &sysctl_tcp_fin_timeout,
 307                 .maxlen         = sizeof(int),
 308                 .mode           = 0644,
 309                 .proc_handler   = proc_dointvec_jiffies,
 310         },
 311 #ifdef CONFIG_SYN_COOKIES
 312         {
 313                 .procname       = "tcp_syncookies",
 314                 .data           = &sysctl_tcp_syncookies,
 315                 .maxlen         = sizeof(int),
 316                 .mode           = 0644,
 317                 .proc_handler   = proc_dointvec
 318         },
 319 #endif
 320         {
 321                 .procname       = "tcp_tw_recycle",
 322                 .data           = &tcp_death_row.sysctl_tw_recycle,
 323                 .maxlen         = sizeof(int),
 324                 .mode           = 0644,
 325                 .proc_handler   = proc_dointvec
 326         },
 327         {
 328                 .procname       = "tcp_abort_on_overflow",
 329                 .data           = &sysctl_tcp_abort_on_overflow,
 330                 .maxlen         = sizeof(int),
 331                 .mode           = 0644,
 332                 .proc_handler   = proc_dointvec
 333         },
 334         {
 335                 .procname       = "tcp_stdurg",
 336                 .data           = &sysctl_tcp_stdurg,
 337                 .maxlen         = sizeof(int),
 338                 .mode           = 0644,
 339                 .proc_handler   = proc_dointvec
 340         },
 341         {
 342                 .procname       = "tcp_rfc1337",
 343                 .data           = &sysctl_tcp_rfc1337,
 344                 .maxlen         = sizeof(int),
 345                 .mode           = 0644,
 346                 .proc_handler   = proc_dointvec
 347         },
 348         {
 349                 .procname       = "tcp_max_syn_backlog",
 350                 .data           = &sysctl_max_syn_backlog,
 351                 .maxlen         = sizeof(int),
 352                 .mode           = 0644,
 353                 .proc_handler   = proc_dointvec
 354         },
 355         {
 356                 .procname       = "ip_local_port_range",
 357                 .data           = &sysctl_local_ports.range,
 358                 .maxlen         = sizeof(sysctl_local_ports.range),
 359                 .mode           = 0644,
 360                 .proc_handler   = ipv4_local_port_range,
 361         },
 362         {
 363                 .procname       = "ip_local_reserved_ports",
 364                 .data           = NULL, /* initialized in sysctl_ipv4_init */
 365                 .maxlen         = 65536,
 366                 .mode           = 0644,
 367                 .proc_handler   = proc_do_large_bitmap,
 368         },
 369         {
 370                 .procname       = "igmp_max_memberships",
 371                 .data           = &sysctl_igmp_max_memberships,
 372                 .maxlen         = sizeof(int),
 373                 .mode           = 0644,
 374                 .proc_handler   = proc_dointvec
 375         },
 376         {
 377                 .procname       = "igmp_max_msf",
 378                 .data           = &sysctl_igmp_max_msf,
 379                 .maxlen         = sizeof(int),
 380                 .mode           = 0644,
 381                 .proc_handler   = proc_dointvec
 382         },
 383         {
 384                 .procname       = "inet_peer_threshold",
 385                 .data           = &inet_peer_threshold,
 386                 .maxlen         = sizeof(int),
 387                 .mode           = 0644,
 388                 .proc_handler   = proc_dointvec
 389         },
 390         {
 391                 .procname       = "inet_peer_minttl",
 392                 .data           = &inet_peer_minttl,
 393                 .maxlen         = sizeof(int),
 394                 .mode           = 0644,
 395                 .proc_handler   = proc_dointvec_jiffies,
 396         },
 397         {
 398                 .procname       = "inet_peer_maxttl",
 399                 .data           = &inet_peer_maxttl,
 400                 .maxlen         = sizeof(int),
 401                 .mode           = 0644,
 402                 .proc_handler   = proc_dointvec_jiffies,
 403         },
 404         {
 405                 .procname       = "tcp_orphan_retries",
 406                 .data           = &sysctl_tcp_orphan_retries,
 407                 .maxlen         = sizeof(int),
 408                 .mode           = 0644,
 409                 .proc_handler   = proc_dointvec
 410         },
 411         {
 412                 .procname       = "tcp_fack",
 413                 .data           = &sysctl_tcp_fack,
 414                 .maxlen         = sizeof(int),
 415                 .mode           = 0644,
 416                 .proc_handler   = proc_dointvec
 417         },
 418         {
 419                 .procname       = "tcp_reordering",
 420                 .data           = &sysctl_tcp_reordering,
 421                 .maxlen         = sizeof(int),
 422                 .mode           = 0644,
 423                 .proc_handler   = proc_dointvec
 424         },
 425         {
 426                 .procname       = "tcp_ecn",
 427                 .data           = &sysctl_tcp_ecn,
 428                 .maxlen         = sizeof(int),
 429                 .mode           = 0644,
 430                 .proc_handler   = proc_dointvec
 431         },
 432         {
 433                 .procname       = "tcp_dsack",
 434                 .data           = &sysctl_tcp_dsack,
 435                 .maxlen         = sizeof(int),
 436                 .mode           = 0644,
 437                 .proc_handler   = proc_dointvec
 438         },
 439         {
 440                 .procname       = "tcp_mem",
 441                 .data           = &sysctl_tcp_mem,
 442                 .maxlen         = sizeof(sysctl_tcp_mem),
 443                 .mode           = 0644,
 444                 .proc_handler   = proc_doulongvec_minmax
 445         },
 446         {
 447                 .procname       = "tcp_wmem",
 448                 .data           = &sysctl_tcp_wmem,
 449                 .maxlen         = sizeof(sysctl_tcp_wmem),
 450                 .mode           = 0644,
 451                 .proc_handler   = proc_dointvec
 452         },
 453         {
 454                 .procname       = "tcp_rmem",
 455                 .data           = &sysctl_tcp_rmem,
 456                 .maxlen         = sizeof(sysctl_tcp_rmem),
 457                 .mode           = 0644,
 458                 .proc_handler   = proc_dointvec
 459         },
 460         {
 461                 .procname       = "tcp_app_win",
 462                 .data           = &sysctl_tcp_app_win,
 463                 .maxlen         = sizeof(int),
 464                 .mode           = 0644,
 465                 .proc_handler   = proc_dointvec
 466         },
 467         {
 468                 .procname       = "tcp_adv_win_scale",
 469                 .data           = &sysctl_tcp_adv_win_scale,
 470                 .maxlen         = sizeof(int),
 471                 .mode           = 0644,
 472                 .proc_handler   = proc_dointvec_minmax,
 473                 .extra1         = &tcp_adv_win_scale_min,
 474                 .extra2         = &tcp_adv_win_scale_max,
 475         },
 476         {
 477                 .procname       = "tcp_tw_reuse",
 478                 .data           = &sysctl_tcp_tw_reuse,
 479                 .maxlen         = sizeof(int),
 480                 .mode           = 0644,
 481                 .proc_handler   = proc_dointvec
 482         },
 483         {
 484                 .procname       = "tcp_frto",
 485                 .data           = &sysctl_tcp_frto,
 486                 .maxlen         = sizeof(int),
 487                 .mode           = 0644,
 488                 .proc_handler   = proc_dointvec
 489         },
 490         {
 491                 .procname       = "tcp_frto_response",
 492                 .data           = &sysctl_tcp_frto_response,
 493                 .maxlen         = sizeof(int),
 494                 .mode           = 0644,
 495                 .proc_handler   = proc_dointvec
 496         },
 497         {
 498                 .procname       = "tcp_low_latency",
 499                 .data           = &sysctl_tcp_low_latency,
 500                 .maxlen         = sizeof(int),
 501                 .mode           = 0644,
 502                 .proc_handler   = proc_dointvec
 503         },
 504         {
 505                 .procname       = "tcp_no_metrics_save",
 506                 .data           = &sysctl_tcp_nometrics_save,
 507                 .maxlen         = sizeof(int),
 508                 .mode           = 0644,
 509                 .proc_handler   = proc_dointvec,
 510         },
 511         {
 512                 .procname       = "tcp_moderate_rcvbuf",
 513                 .data           = &sysctl_tcp_moderate_rcvbuf,
 514                 .maxlen         = sizeof(int),
 515                 .mode           = 0644,
 516                 .proc_handler   = proc_dointvec,
 517         },
 518         {
 519                 .procname       = "tcp_tso_win_divisor",
 520                 .data           = &sysctl_tcp_tso_win_divisor,
 521                 .maxlen         = sizeof(int),
 522                 .mode           = 0644,
 523                 .proc_handler   = proc_dointvec,
 524         },
 525         {
 526                 .procname       = "tcp_congestion_control",
 527                 .mode           = 0644,
 528                 .maxlen         = TCP_CA_NAME_MAX,
 529                 .proc_handler   = proc_tcp_congestion_control,
 530         },
 531         {
 532                 .procname       = "tcp_abc",
 533                 .data           = &sysctl_tcp_abc,
 534                 .maxlen         = sizeof(int),
 535                 .mode           = 0644,
 536                 .proc_handler   = proc_dointvec,
 537         },
 538         {
 539                 .procname       = "tcp_mtu_probing",
 540                 .data           = &sysctl_tcp_mtu_probing,
 541                 .maxlen         = sizeof(int),
 542                 .mode           = 0644,
 543                 .proc_handler   = proc_dointvec,
 544         },
 545         {
 546                 .procname       = "tcp_base_mss",
 547                 .data           = &sysctl_tcp_base_mss,
 548                 .maxlen         = sizeof(int),
 549                 .mode           = 0644,
 550                 .proc_handler   = proc_dointvec,
 551         },
 552         {
 553                 .procname       = "tcp_workaround_signed_windows",
 554                 .data           = &sysctl_tcp_workaround_signed_windows,
 555                 .maxlen         = sizeof(int),
 556                 .mode           = 0644,
 557                 .proc_handler   = proc_dointvec
 558         },
 559         {
 560                 .procname       = "tcp_challenge_ack_limit",
 561                 .data           = &sysctl_tcp_challenge_ack_limit,
 562                 .maxlen         = sizeof(int),
 563                 .mode           = 0644,
 564                 .proc_handler   = proc_dointvec
 565         },
 566 #ifdef CONFIG_NET_DMA
 567         {
 568                 .procname       = "tcp_dma_copybreak",
 569                 .data           = &sysctl_tcp_dma_copybreak,
 570                 .maxlen         = sizeof(int),
 571                 .mode           = 0644,
 572                 .proc_handler   = proc_dointvec
 573         },
 574 #endif
 575         {
 576                 .procname       = "tcp_slow_start_after_idle",
 577                 .data           = &sysctl_tcp_slow_start_after_idle,
 578                 .maxlen         = sizeof(int),
 579                 .mode           = 0644,
 580                 .proc_handler   = proc_dointvec
 581         },
 582 #ifdef CONFIG_NETLABEL
 583         {
 584                 .procname       = "cipso_cache_enable",
 585                 .data           = &cipso_v4_cache_enabled,
 586                 .maxlen         = sizeof(int),
 587                 .mode           = 0644,
 588                 .proc_handler   = proc_dointvec,
 589         },
 590         {
 591                 .procname       = "cipso_cache_bucket_size",
 592                 .data           = &cipso_v4_cache_bucketsize,
 593                 .maxlen         = sizeof(int),
 594                 .mode           = 0644,
 595                 .proc_handler   = proc_dointvec,
 596         },
 597         {
 598                 .procname       = "cipso_rbm_optfmt",
 599                 .data           = &cipso_v4_rbm_optfmt,
 600                 .maxlen         = sizeof(int),
 601                 .mode           = 0644,
 602                 .proc_handler   = proc_dointvec,
 603         },
 604         {
 605                 .procname       = "cipso_rbm_strictvalid",
 606                 .data           = &cipso_v4_rbm_strictvalid,
 607                 .maxlen         = sizeof(int),
 608                 .mode           = 0644,
 609                 .proc_handler   = proc_dointvec,
 610         },
 611 #endif /* CONFIG_NETLABEL */
 612         {
 613                 .procname       = "tcp_available_congestion_control",
 614                 .maxlen         = TCP_CA_BUF_MAX,
 615                 .mode           = 0444,
 616                 .proc_handler   = proc_tcp_available_congestion_control,
 617         },
 618         {
 619                 .procname       = "tcp_allowed_congestion_control",
 620                 .maxlen         = TCP_CA_BUF_MAX,
 621                 .mode           = 0644,
 622                 .proc_handler   = proc_allowed_congestion_control,
 623         },
 624         {
 625                 .procname       = "tcp_max_ssthresh",
 626                 .data           = &sysctl_tcp_max_ssthresh,
 627                 .maxlen         = sizeof(int),
 628                 .mode           = 0644,
 629                 .proc_handler   = proc_dointvec,
 630         },
 631         {
 632                 .procname       = "tcp_cookie_size",
 633                 .data           = &sysctl_tcp_cookie_size,
 634                 .maxlen         = sizeof(int),
 635                 .mode           = 0644,
 636                 .proc_handler   = proc_dointvec
 637         },
 638         {
 639                 .procname       = "tcp_thin_linear_timeouts",
 640                 .data           = &sysctl_tcp_thin_linear_timeouts,
 641                 .maxlen         = sizeof(int),
 642                 .mode           = 0644,
 643                 .proc_handler   = proc_dointvec
 644         },
 645         {
 646                 .procname       = "tcp_thin_dupack",
 647                 .data           = &sysctl_tcp_thin_dupack,
 648                 .maxlen         = sizeof(int),
 649                 .mode           = 0644,
 650                 .proc_handler   = proc_dointvec
 651         },
 652         {
 653                 .procname       = "udp_mem",
 654                 .data           = &sysctl_udp_mem,
 655                 .maxlen         = sizeof(sysctl_udp_mem),
 656                 .mode           = 0644,
 657                 .proc_handler   = proc_doulongvec_minmax,
 658         },
 659         {
 660                 .procname       = "udp_rmem_min",
 661                 .data           = &sysctl_udp_rmem_min,
 662                 .maxlen         = sizeof(sysctl_udp_rmem_min),
 663                 .mode           = 0644,
 664                 .proc_handler   = proc_dointvec_minmax,
 665                 .extra1         = &zero
 666         },
 667         {
 668                 .procname       = "udp_wmem_min",
 669                 .data           = &sysctl_udp_wmem_min,
 670                 .maxlen         = sizeof(sysctl_udp_wmem_min),
 671                 .mode           = 0644,
 672                 .proc_handler   = proc_dointvec_minmax,
 673                 .extra1         = &zero
 674         },
 675         { }
 676 };
 677
 678 static struct ctl_table ipv4_net_table[] = {
 679         {
 680                 .procname       = "icmp_echo_ignore_all",
 681                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
 682                 .maxlen         = sizeof(int),
 683                 .mode           = 0644,
 684                 .proc_handler   = proc_dointvec
 685         },
 686         {
 687                 .procname       = "icmp_echo_ignore_broadcasts",
 688                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
 689                 .maxlen         = sizeof(int),
 690                 .mode           = 0644,
 691                 .proc_handler   = proc_dointvec
 692         },
 693         {
 694                 .procname       = "icmp_ignore_bogus_error_responses",
 695                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
 696                 .maxlen         = sizeof(int),
 697                 .mode           = 0644,
 698                 .proc_handler   = proc_dointvec
 699         },
 700         {
 701                 .procname       = "icmp_errors_use_inbound_ifaddr",
 702                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
 703                 .maxlen         = sizeof(int),
 704                 .mode           = 0644,
 705                 .proc_handler   = proc_dointvec
 706         },
 707         {
 708                 .procname       = "icmp_ratelimit",
 709                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
 710                 .maxlen         = sizeof(int),
 711                 .mode           = 0644,
 712                 .proc_handler   = proc_dointvec_ms_jiffies,
 713         },
 714         {
 715                 .procname       = "icmp_ratemask",
 716                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
 717                 .maxlen         = sizeof(int),
 718                 .mode           = 0644,
 719                 .proc_handler   = proc_dointvec
 720         },
 721         {
 722                 .procname       = "rt_cache_rebuild_count",
 723                 .data           = &init_net.ipv4.sysctl_rt_cache_rebuild_count,
 724                 .maxlen         = sizeof(int),
 725                 .mode           = 0644,
 726                 .proc_handler   = proc_dointvec
 727         },
 728         {
 729                 .procname       = "ping_group_range",
 730                 .data           = &init_net.ipv4.sysctl_ping_group_range,
 731                 .maxlen         = sizeof(init_net.ipv4.sysctl_ping_group_range),
 732                 .mode           = 0644,
 733                 .proc_handler   = ipv4_ping_group_range,
 734         },
 735         { }
 736 };
 737
 738 struct ctl_path net_ipv4_ctl_path[] = {
 739         { .procname = "net", },
 740         { .procname = "ipv4", },
 741         { },
 742 };
 743 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
 744
 745 static __net_init int ipv4_sysctl_init_net(struct net *net)
 746 {
 747         struct ctl_table *table;
 748
 749         table = ipv4_net_table;
 750         if (!net_eq(net, &init_net)) {
 751                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
 752                 if (table == NULL)
 753                         goto err_alloc;
 754
 755                 table[0].data =
 756                         &net->ipv4.sysctl_icmp_echo_ignore_all;
 757                 table[1].data =
 758                         &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
 759                 table[2].data =
 760                         &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
 761                 table[3].data =
 762                         &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
 763                 table[4].data =
 764                         &net->ipv4.sysctl_icmp_ratelimit;
 765                 table[5].data =
 766                         &net->ipv4.sysctl_icmp_ratemask;
 767                 table[6].data =
 768                         &net->ipv4.sysctl_rt_cache_rebuild_count;
 769                 table[7].data =
 770                         &net->ipv4.sysctl_ping_group_range;
 771
 772         }
 773
 774         /*
 775          * Sane defaults - nobody may create ping sockets.
 776          * Boot scripts should set this to distro-specific group.
 777          */
 778         net->ipv4.sysctl_ping_group_range[0] = 1;
 779         net->ipv4.sysctl_ping_group_range[1] = 0;
 780
 781         net->ipv4.sysctl_rt_cache_rebuild_count = 4;
 782
 783         net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
 784                         net_ipv4_ctl_path, table);
 785         if (net->ipv4.ipv4_hdr == NULL)
 786                 goto err_reg;
 787
 788         return 0;
 789
 790 err_reg:
 791         if (!net_eq(net, &init_net))
 792                 kfree(table);
 793 err_alloc:
 794         return -ENOMEM;
 795 }
 796
 797 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
 798 {
 799         struct ctl_table *table;
 800
 801         table = net->ipv4.ipv4_hdr->ctl_table_arg;
 802         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
 803         kfree(table);
 804 }
 805
 806 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
 807         .init = ipv4_sysctl_init_net,
 808         .exit = ipv4_sysctl_exit_net,
 809 };
 810
 811 static __init int sysctl_ipv4_init(void)
 812 {
 813         struct ctl_table_header *hdr;
 814         struct ctl_table *i;
 815
 816         for (i = ipv4_table; i->procname; i++) {
 817                 if (strcmp(i->procname, "ip_local_reserved_ports") == 0) {
 818                         i->data = sysctl_local_reserved_ports;
 819                         break;
 820                 }
 821         }
 822         if (!i->procname)
 823                 return -EINVAL;
 824
 825         hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table);
 826         if (hdr == NULL)
 827                 return -ENOMEM;
 828
 829         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
 830                 unregister_sysctl_table(hdr);
 831                 return -ENOMEM;
 832         }
 833
 834         return 0;
 835 }
 836
 837 __initcall(sysctl_ipv4_init);