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 <net/snmp.h>
  17 #include <net/icmp.h>
  18 #include <net/ip.h>
  19 #include <net/route.h>
  20 #include <net/tcp.h>
  21 #include <net/udp.h>
  22 #include <net/cipso_ipv4.h>
  23 #include <net/inet_frag.h>
  24
  25 static int zero;
  26 static int tcp_retr1_max = 255;
  27 static int ip_local_port_range_min[] = { 1, 1 };
  28 static int ip_local_port_range_max[] = { 65535, 65535 };
  29 static int tcp_adv_win_scale_min = -31;
  30 static int tcp_adv_win_scale_max = 31;
  31
  32 /* Update system visible IP port range */
  33 static void set_local_port_range(int range[2])
  34 {
  35         write_seqlock(&sysctl_local_ports.lock);
  36         sysctl_local_ports.range[0] = range[0];
  37         sysctl_local_ports.range[1] = range[1];
  38         write_sequnlock(&sysctl_local_ports.lock);
  39 }
  40
  41 /* Validate changes from /proc interface. */
  42 static int ipv4_local_port_range(ctl_table *table, int write,
  43                                  void __user *buffer,
  44                                  size_t *lenp, loff_t *ppos)
  45 {
  46         int ret;
  47         int range[2];
  48         ctl_table tmp = {
  49                 .data = &range,
  50                 .maxlen = sizeof(range),
  51                 .mode = table->mode,
  52                 .extra1 = &ip_local_port_range_min,
  53                 .extra2 = &ip_local_port_range_max,
  54         };
  55
  56         inet_get_local_port_range(range, range + 1);
  57         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
  58
  59         if (write && ret == 0) {
  60                 if (range[1] < range[0])
  61                         ret = -EINVAL;
  62                 else
  63                         set_local_port_range(range);
  64         }
  65
  66         return ret;
  67 }
  68
  69 static int proc_tcp_congestion_control(ctl_table *ctl, int write,
  70                                        void __user *buffer, size_t *lenp, loff_t *ppos)
  71 {
  72         char val[TCP_CA_NAME_MAX];
  73         ctl_table tbl = {
  74                 .data = val,
  75                 .maxlen = TCP_CA_NAME_MAX,
  76         };
  77         int ret;
  78
  79         tcp_get_default_congestion_control(val);
  80
  81         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
  82         if (write && ret == 0)
  83                 ret = tcp_set_default_congestion_control(val);
  84         return ret;
  85 }
  86
  87 static int proc_tcp_available_congestion_control(ctl_table *ctl,
  88                                                  int write,
  89                                                  void __user *buffer, size_t *lenp,
  90                                                  loff_t *ppos)
  91 {
  92         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
  93         int ret;
  94
  95         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
  96         if (!tbl.data)
  97                 return -ENOMEM;
  98         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
  99         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 100         kfree(tbl.data);
 101         return ret;
 102 }
 103
 104 static int proc_allowed_congestion_control(ctl_table *ctl,
 105                                            int write,
 106                                            void __user *buffer, size_t *lenp,
 107                                            loff_t *ppos)
 108 {
 109         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 110         int ret;
 111
 112         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 113         if (!tbl.data)
 114                 return -ENOMEM;
 115
 116         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
 117         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 118         if (write && ret == 0)
 119                 ret = tcp_set_allowed_congestion_control(tbl.data);
 120         kfree(tbl.data);
 121         return ret;
 122 }
 123
 124 static struct ctl_table ipv4_table[] = {
 125         {
 126                 .procname       = "tcp_timestamps",
 127                 .data           = &sysctl_tcp_timestamps,
 128                 .maxlen         = sizeof(int),
 129                 .mode           = 0644,
 130                 .proc_handler   = proc_dointvec
 131         },
 132         {
 133                 .procname       = "tcp_window_scaling",
 134                 .data           = &sysctl_tcp_window_scaling,
 135                 .maxlen         = sizeof(int),
 136                 .mode           = 0644,
 137                 .proc_handler   = proc_dointvec
 138         },
 139         {
 140                 .procname       = "tcp_sack",
 141                 .data           = &sysctl_tcp_sack,
 142                 .maxlen         = sizeof(int),
 143                 .mode           = 0644,
 144                 .proc_handler   = proc_dointvec
 145         },
 146         {
 147                 .procname       = "tcp_retrans_collapse",
 148                 .data           = &sysctl_tcp_retrans_collapse,
 149                 .maxlen         = sizeof(int),
 150                 .mode           = 0644,
 151                 .proc_handler   = proc_dointvec
 152         },
 153         {
 154                 .procname       = "ip_default_ttl",
 155                 .data           = &sysctl_ip_default_ttl,
 156                 .maxlen         = sizeof(int),
 157                 .mode           = 0644,
 158                 .proc_handler   = ipv4_doint_and_flush,
 159                 .extra2         = &init_net,
 160         },
 161         {
 162                 .procname       = "ip_no_pmtu_disc",
 163                 .data           = &ipv4_config.no_pmtu_disc,
 164                 .maxlen         = sizeof(int),
 165                 .mode           = 0644,
 166                 .proc_handler   = proc_dointvec
 167         },
 168         {
 169                 .procname       = "ip_nonlocal_bind",
 170                 .data           = &sysctl_ip_nonlocal_bind,
 171                 .maxlen         = sizeof(int),
 172                 .mode           = 0644,
 173                 .proc_handler   = proc_dointvec
 174         },
 175         {
 176                 .procname       = "tcp_syn_retries",
 177                 .data           = &sysctl_tcp_syn_retries,
 178                 .maxlen         = sizeof(int),
 179                 .mode           = 0644,
 180                 .proc_handler   = proc_dointvec
 181         },
 182         {
 183                 .procname       = "tcp_synack_retries",
 184                 .data           = &sysctl_tcp_synack_retries,
 185                 .maxlen         = sizeof(int),
 186                 .mode           = 0644,
 187                 .proc_handler   = proc_dointvec
 188         },
 189         {
 190                 .procname       = "tcp_max_orphans",
 191                 .data           = &sysctl_tcp_max_orphans,
 192                 .maxlen         = sizeof(int),
 193                 .mode           = 0644,
 194                 .proc_handler   = proc_dointvec
 195         },
 196         {
 197                 .procname       = "tcp_max_tw_buckets",
 198                 .data           = &tcp_death_row.sysctl_max_tw_buckets,
 199                 .maxlen         = sizeof(int),
 200                 .mode           = 0644,
 201                 .proc_handler   = proc_dointvec
 202         },
 203         {
 204                 .procname       = "ip_dynaddr",
 205                 .data           = &sysctl_ip_dynaddr,
 206                 .maxlen         = sizeof(int),
 207                 .mode           = 0644,
 208                 .proc_handler   = proc_dointvec
 209         },
 210         {
 211                 .procname       = "tcp_keepalive_time",
 212                 .data           = &sysctl_tcp_keepalive_time,
 213                 .maxlen         = sizeof(int),
 214                 .mode           = 0644,
 215                 .proc_handler   = proc_dointvec_jiffies,
 216         },
 217         {
 218                 .procname       = "tcp_keepalive_probes",
 219                 .data           = &sysctl_tcp_keepalive_probes,
 220                 .maxlen         = sizeof(int),
 221                 .mode           = 0644,
 222                 .proc_handler   = proc_dointvec
 223         },
 224         {
 225                 .procname       = "tcp_keepalive_intvl",
 226                 .data           = &sysctl_tcp_keepalive_intvl,
 227                 .maxlen         = sizeof(int),
 228                 .mode           = 0644,
 229                 .proc_handler   = proc_dointvec_jiffies,
 230         },
 231         {
 232                 .procname       = "tcp_retries1",
 233                 .data           = &sysctl_tcp_retries1,
 234                 .maxlen         = sizeof(int),
 235                 .mode           = 0644,
 236                 .proc_handler   = proc_dointvec_minmax,
 237                 .extra2         = &tcp_retr1_max
 238         },
 239         {
 240                 .procname       = "tcp_retries2",
 241                 .data           = &sysctl_tcp_retries2,
 242                 .maxlen         = sizeof(int),
 243                 .mode           = 0644,
 244                 .proc_handler   = proc_dointvec
 245         },
 246         {
 247                 .procname       = "tcp_fin_timeout",
 248                 .data           = &sysctl_tcp_fin_timeout,
 249                 .maxlen         = sizeof(int),
 250                 .mode           = 0644,
 251                 .proc_handler   = proc_dointvec_jiffies,
 252         },
 253 #ifdef CONFIG_SYN_COOKIES
 254         {
 255                 .procname       = "tcp_syncookies",
 256                 .data           = &sysctl_tcp_syncookies,
 257                 .maxlen         = sizeof(int),
 258                 .mode           = 0644,
 259                 .proc_handler   = proc_dointvec
 260         },
 261 #endif
 262         {
 263                 .procname       = "tcp_tw_recycle",
 264                 .data           = &tcp_death_row.sysctl_tw_recycle,
 265                 .maxlen         = sizeof(int),
 266                 .mode           = 0644,
 267                 .proc_handler   = proc_dointvec
 268         },
 269         {
 270                 .procname       = "tcp_abort_on_overflow",
 271                 .data           = &sysctl_tcp_abort_on_overflow,
 272                 .maxlen         = sizeof(int),
 273                 .mode           = 0644,
 274                 .proc_handler   = proc_dointvec
 275         },
 276         {
 277                 .procname       = "tcp_stdurg",
 278                 .data           = &sysctl_tcp_stdurg,
 279                 .maxlen         = sizeof(int),
 280                 .mode           = 0644,
 281                 .proc_handler   = proc_dointvec
 282         },
 283         {
 284                 .procname       = "tcp_rfc1337",
 285                 .data           = &sysctl_tcp_rfc1337,
 286                 .maxlen         = sizeof(int),
 287                 .mode           = 0644,
 288                 .proc_handler   = proc_dointvec
 289         },
 290         {
 291                 .procname       = "tcp_max_syn_backlog",
 292                 .data           = &sysctl_max_syn_backlog,
 293                 .maxlen         = sizeof(int),
 294                 .mode           = 0644,
 295                 .proc_handler   = proc_dointvec
 296         },
 297         {
 298                 .procname       = "ip_local_port_range",
 299                 .data           = &sysctl_local_ports.range,
 300                 .maxlen         = sizeof(sysctl_local_ports.range),
 301                 .mode           = 0644,
 302                 .proc_handler   = ipv4_local_port_range,
 303         },
 304         {
 305                 .procname       = "ip_local_reserved_ports",
 306                 .data           = NULL, /* initialized in sysctl_ipv4_init */
 307                 .maxlen         = 65536,
 308                 .mode           = 0644,
 309                 .proc_handler   = proc_do_large_bitmap,
 310         },
 311 #ifdef CONFIG_IP_MULTICAST
 312         {
 313                 .procname       = "igmp_max_memberships",
 314                 .data           = &sysctl_igmp_max_memberships,
 315                 .maxlen         = sizeof(int),
 316                 .mode           = 0644,
 317                 .proc_handler   = proc_dointvec
 318         },
 319
 320 #endif
 321         {
 322                 .procname       = "igmp_max_msf",
 323                 .data           = &sysctl_igmp_max_msf,
 324                 .maxlen         = sizeof(int),
 325                 .mode           = 0644,
 326                 .proc_handler   = proc_dointvec
 327         },
 328         {
 329                 .procname       = "inet_peer_threshold",
 330                 .data           = &inet_peer_threshold,
 331                 .maxlen         = sizeof(int),
 332                 .mode           = 0644,
 333                 .proc_handler   = proc_dointvec
 334         },
 335         {
 336                 .procname       = "inet_peer_minttl",
 337                 .data           = &inet_peer_minttl,
 338                 .maxlen         = sizeof(int),
 339                 .mode           = 0644,
 340                 .proc_handler   = proc_dointvec_jiffies,
 341         },
 342         {
 343                 .procname       = "inet_peer_maxttl",
 344                 .data           = &inet_peer_maxttl,
 345                 .maxlen         = sizeof(int),
 346                 .mode           = 0644,
 347                 .proc_handler   = proc_dointvec_jiffies,
 348         },
 349         {
 350                 .procname       = "inet_peer_gc_mintime",
 351                 .data           = &inet_peer_gc_mintime,
 352                 .maxlen         = sizeof(int),
 353                 .mode           = 0644,
 354                 .proc_handler   = proc_dointvec_jiffies,
 355         },
 356         {
 357                 .procname       = "inet_peer_gc_maxtime",
 358                 .data           = &inet_peer_gc_maxtime,
 359                 .maxlen         = sizeof(int),
 360                 .mode           = 0644,
 361                 .proc_handler   = proc_dointvec_jiffies,
 362         },
 363         {
 364                 .procname       = "tcp_orphan_retries",
 365                 .data           = &sysctl_tcp_orphan_retries,
 366                 .maxlen         = sizeof(int),
 367                 .mode           = 0644,
 368                 .proc_handler   = proc_dointvec
 369         },
 370         {
 371                 .procname       = "tcp_fack",
 372                 .data           = &sysctl_tcp_fack,
 373                 .maxlen         = sizeof(int),
 374                 .mode           = 0644,
 375                 .proc_handler   = proc_dointvec
 376         },
 377         {
 378                 .procname       = "tcp_reordering",
 379                 .data           = &sysctl_tcp_reordering,
 380                 .maxlen         = sizeof(int),
 381                 .mode           = 0644,
 382                 .proc_handler   = proc_dointvec
 383         },
 384         {
 385                 .procname       = "tcp_ecn",
 386                 .data           = &sysctl_tcp_ecn,
 387                 .maxlen         = sizeof(int),
 388                 .mode           = 0644,
 389                 .proc_handler   = proc_dointvec
 390         },
 391         {
 392                 .procname       = "tcp_dsack",
 393                 .data           = &sysctl_tcp_dsack,
 394                 .maxlen         = sizeof(int),
 395                 .mode           = 0644,
 396                 .proc_handler   = proc_dointvec
 397         },
 398         {
 399                 .procname       = "tcp_mem",
 400                 .data           = &sysctl_tcp_mem,
 401                 .maxlen         = sizeof(sysctl_tcp_mem),
 402                 .mode           = 0644,
 403                 .proc_handler   = proc_doulongvec_minmax
 404         },
 405         {
 406                 .procname       = "tcp_wmem",
 407                 .data           = &sysctl_tcp_wmem,
 408                 .maxlen         = sizeof(sysctl_tcp_wmem),
 409                 .mode           = 0644,
 410                 .proc_handler   = proc_dointvec
 411         },
 412         {
 413                 .procname       = "tcp_rmem",
 414                 .data           = &sysctl_tcp_rmem,
 415                 .maxlen         = sizeof(sysctl_tcp_rmem),
 416                 .mode           = 0644,
 417                 .proc_handler   = proc_dointvec
 418         },
 419         {
 420                 .procname       = "tcp_app_win",
 421                 .data           = &sysctl_tcp_app_win,
 422                 .maxlen         = sizeof(int),
 423                 .mode           = 0644,
 424                 .proc_handler   = proc_dointvec
 425         },
 426         {
 427                 .procname       = "tcp_adv_win_scale",
 428                 .data           = &sysctl_tcp_adv_win_scale,
 429                 .maxlen         = sizeof(int),
 430                 .mode           = 0644,
 431                 .proc_handler   = proc_dointvec_minmax,
 432                 .extra1         = &tcp_adv_win_scale_min,
 433                 .extra2         = &tcp_adv_win_scale_max,
 434         },
 435         {
 436                 .procname       = "tcp_tw_reuse",
 437                 .data           = &sysctl_tcp_tw_reuse,
 438                 .maxlen         = sizeof(int),
 439                 .mode           = 0644,
 440                 .proc_handler   = proc_dointvec
 441         },
 442         {
 443                 .procname       = "tcp_frto",
 444                 .data           = &sysctl_tcp_frto,
 445                 .maxlen         = sizeof(int),
 446                 .mode           = 0644,
 447                 .proc_handler   = proc_dointvec
 448         },
 449         {
 450                 .procname       = "tcp_frto_response",
 451                 .data           = &sysctl_tcp_frto_response,
 452                 .maxlen         = sizeof(int),
 453                 .mode           = 0644,
 454                 .proc_handler   = proc_dointvec
 455         },
 456         {
 457                 .procname       = "tcp_low_latency",
 458                 .data           = &sysctl_tcp_low_latency,
 459                 .maxlen         = sizeof(int),
 460                 .mode           = 0644,
 461                 .proc_handler   = proc_dointvec
 462         },
 463         {
 464                 .procname       = "tcp_no_metrics_save",
 465                 .data           = &sysctl_tcp_nometrics_save,
 466                 .maxlen         = sizeof(int),
 467                 .mode           = 0644,
 468                 .proc_handler   = proc_dointvec,
 469         },
 470         {
 471                 .procname       = "tcp_moderate_rcvbuf",
 472                 .data           = &sysctl_tcp_moderate_rcvbuf,
 473                 .maxlen         = sizeof(int),
 474                 .mode           = 0644,
 475                 .proc_handler   = proc_dointvec,
 476         },
 477         {
 478                 .procname       = "tcp_tso_win_divisor",
 479                 .data           = &sysctl_tcp_tso_win_divisor,
 480                 .maxlen         = sizeof(int),
 481                 .mode           = 0644,
 482                 .proc_handler   = proc_dointvec,
 483         },
 484         {
 485                 .procname       = "tcp_congestion_control",
 486                 .mode           = 0644,
 487                 .maxlen         = TCP_CA_NAME_MAX,
 488                 .proc_handler   = proc_tcp_congestion_control,
 489         },
 490         {
 491                 .procname       = "tcp_abc",
 492                 .data           = &sysctl_tcp_abc,
 493                 .maxlen         = sizeof(int),
 494                 .mode           = 0644,
 495                 .proc_handler   = proc_dointvec,
 496         },
 497         {
 498                 .procname       = "tcp_mtu_probing",
 499                 .data           = &sysctl_tcp_mtu_probing,
 500                 .maxlen         = sizeof(int),
 501                 .mode           = 0644,
 502                 .proc_handler   = proc_dointvec,
 503         },
 504         {
 505                 .procname       = "tcp_base_mss",
 506                 .data           = &sysctl_tcp_base_mss,
 507                 .maxlen         = sizeof(int),
 508                 .mode           = 0644,
 509                 .proc_handler   = proc_dointvec,
 510         },
 511         {
 512                 .procname       = "tcp_workaround_signed_windows",
 513                 .data           = &sysctl_tcp_workaround_signed_windows,
 514                 .maxlen         = sizeof(int),
 515                 .mode           = 0644,
 516                 .proc_handler   = proc_dointvec
 517         },
 518 #ifdef CONFIG_NET_DMA
 519         {
 520                 .procname       = "tcp_dma_copybreak",
 521                 .data           = &sysctl_tcp_dma_copybreak,
 522                 .maxlen         = sizeof(int),
 523                 .mode           = 0644,
 524                 .proc_handler   = proc_dointvec
 525         },
 526 #endif
 527         {
 528                 .procname       = "tcp_slow_start_after_idle",
 529                 .data           = &sysctl_tcp_slow_start_after_idle,
 530                 .maxlen         = sizeof(int),
 531                 .mode           = 0644,
 532                 .proc_handler   = proc_dointvec
 533         },
 534 #ifdef CONFIG_NETLABEL
 535         {
 536                 .procname       = "cipso_cache_enable",
 537                 .data           = &cipso_v4_cache_enabled,
 538                 .maxlen         = sizeof(int),
 539                 .mode           = 0644,
 540                 .proc_handler   = proc_dointvec,
 541         },
 542         {
 543                 .procname       = "cipso_cache_bucket_size",
 544                 .data           = &cipso_v4_cache_bucketsize,
 545                 .maxlen         = sizeof(int),
 546                 .mode           = 0644,
 547                 .proc_handler   = proc_dointvec,
 548         },
 549         {
 550                 .procname       = "cipso_rbm_optfmt",
 551                 .data           = &cipso_v4_rbm_optfmt,
 552                 .maxlen         = sizeof(int),
 553                 .mode           = 0644,
 554                 .proc_handler   = proc_dointvec,
 555         },
 556         {
 557                 .procname       = "cipso_rbm_strictvalid",
 558                 .data           = &cipso_v4_rbm_strictvalid,
 559                 .maxlen         = sizeof(int),
 560                 .mode           = 0644,
 561                 .proc_handler   = proc_dointvec,
 562         },
 563 #endif /* CONFIG_NETLABEL */
 564         {
 565                 .procname       = "tcp_available_congestion_control",
 566                 .maxlen         = TCP_CA_BUF_MAX,
 567                 .mode           = 0444,
 568                 .proc_handler   = proc_tcp_available_congestion_control,
 569         },
 570         {
 571                 .procname       = "tcp_allowed_congestion_control",
 572                 .maxlen         = TCP_CA_BUF_MAX,
 573                 .mode           = 0644,
 574                 .proc_handler   = proc_allowed_congestion_control,
 575         },
 576         {
 577                 .procname       = "tcp_max_ssthresh",
 578                 .data           = &sysctl_tcp_max_ssthresh,
 579                 .maxlen         = sizeof(int),
 580                 .mode           = 0644,
 581                 .proc_handler   = proc_dointvec,
 582         },
 583         {
 584                 .procname       = "tcp_cookie_size",
 585                 .data           = &sysctl_tcp_cookie_size,
 586                 .maxlen         = sizeof(int),
 587                 .mode           = 0644,
 588                 .proc_handler   = proc_dointvec
 589         },
 590         {
 591                 .procname       = "tcp_thin_linear_timeouts",
 592                 .data           = &sysctl_tcp_thin_linear_timeouts,
 593                 .maxlen         = sizeof(int),
 594                 .mode           = 0644,
 595                 .proc_handler   = proc_dointvec
 596         },
 597         {
 598                 .procname       = "tcp_thin_dupack",
 599                 .data           = &sysctl_tcp_thin_dupack,
 600                 .maxlen         = sizeof(int),
 601                 .mode           = 0644,
 602                 .proc_handler   = proc_dointvec
 603         },
 604         {
 605                 .procname       = "udp_mem",
 606                 .data           = &sysctl_udp_mem,
 607                 .maxlen         = sizeof(sysctl_udp_mem),
 608                 .mode           = 0644,
 609                 .proc_handler   = proc_doulongvec_minmax,
 610         },
 611         {
 612                 .procname       = "udp_rmem_min",
 613                 .data           = &sysctl_udp_rmem_min,
 614                 .maxlen         = sizeof(sysctl_udp_rmem_min),
 615                 .mode           = 0644,
 616                 .proc_handler   = proc_dointvec_minmax,
 617                 .extra1         = &zero
 618         },
 619         {
 620                 .procname       = "udp_wmem_min",
 621                 .data           = &sysctl_udp_wmem_min,
 622                 .maxlen         = sizeof(sysctl_udp_wmem_min),
 623                 .mode           = 0644,
 624                 .proc_handler   = proc_dointvec_minmax,
 625                 .extra1         = &zero
 626         },
 627         { }
 628 };
 629
 630 static struct ctl_table ipv4_net_table[] = {
 631         {
 632                 .procname       = "icmp_echo_ignore_all",
 633                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
 634                 .maxlen         = sizeof(int),
 635                 .mode           = 0644,
 636                 .proc_handler   = proc_dointvec
 637         },
 638         {
 639                 .procname       = "icmp_echo_ignore_broadcasts",
 640                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
 641                 .maxlen         = sizeof(int),
 642                 .mode           = 0644,
 643                 .proc_handler   = proc_dointvec
 644         },
 645         {
 646                 .procname       = "icmp_ignore_bogus_error_responses",
 647                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
 648                 .maxlen         = sizeof(int),
 649                 .mode           = 0644,
 650                 .proc_handler   = proc_dointvec
 651         },
 652         {
 653                 .procname       = "icmp_errors_use_inbound_ifaddr",
 654                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
 655                 .maxlen         = sizeof(int),
 656                 .mode           = 0644,
 657                 .proc_handler   = proc_dointvec
 658         },
 659         {
 660                 .procname       = "icmp_ratelimit",
 661                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
 662                 .maxlen         = sizeof(int),
 663                 .mode           = 0644,
 664                 .proc_handler   = proc_dointvec_ms_jiffies,
 665         },
 666         {
 667                 .procname       = "icmp_ratemask",
 668                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
 669                 .maxlen         = sizeof(int),
 670                 .mode           = 0644,
 671                 .proc_handler   = proc_dointvec
 672         },
 673         {
 674                 .procname       = "rt_cache_rebuild_count",
 675                 .data           = &init_net.ipv4.sysctl_rt_cache_rebuild_count,
 676                 .maxlen         = sizeof(int),
 677                 .mode           = 0644,
 678                 .proc_handler   = proc_dointvec
 679         },
 680         { }
 681 };
 682
 683 struct ctl_path net_ipv4_ctl_path[] = {
 684         { .procname = "net", },
 685         { .procname = "ipv4", },
 686         { },
 687 };
 688 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
 689
 690 static __net_init int ipv4_sysctl_init_net(struct net *net)
 691 {
 692         struct ctl_table *table;
 693
 694         table = ipv4_net_table;
 695         if (!net_eq(net, &init_net)) {
 696                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
 697                 if (table == NULL)
 698                         goto err_alloc;
 699
 700                 table[0].data =
 701                         &net->ipv4.sysctl_icmp_echo_ignore_all;
 702                 table[1].data =
 703                         &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
 704                 table[2].data =
 705                         &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
 706                 table[3].data =
 707                         &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
 708                 table[4].data =
 709                         &net->ipv4.sysctl_icmp_ratelimit;
 710                 table[5].data =
 711                         &net->ipv4.sysctl_icmp_ratemask;
 712                 table[6].data =
 713                         &net->ipv4.sysctl_rt_cache_rebuild_count;
 714         }
 715
 716         net->ipv4.sysctl_rt_cache_rebuild_count = 4;
 717
 718         net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
 719                         net_ipv4_ctl_path, table);
 720         if (net->ipv4.ipv4_hdr == NULL)
 721                 goto err_reg;
 722
 723         return 0;
 724
 725 err_reg:
 726         if (!net_eq(net, &init_net))
 727                 kfree(table);
 728 err_alloc:
 729         return -ENOMEM;
 730 }
 731
 732 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
 733 {
 734         struct ctl_table *table;
 735
 736         table = net->ipv4.ipv4_hdr->ctl_table_arg;
 737         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
 738         kfree(table);
 739 }
 740
 741 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
 742         .init = ipv4_sysctl_init_net,
 743         .exit = ipv4_sysctl_exit_net,
 744 };
 745
 746 static __init int sysctl_ipv4_init(void)
 747 {
 748         struct ctl_table_header *hdr;
 749         struct ctl_table *i;
 750
 751         for (i = ipv4_table; i->procname; i++) {
 752                 if (strcmp(i->procname, "ip_local_reserved_ports") == 0) {
 753                         i->data = sysctl_local_reserved_ports;
 754                         break;
 755                 }
 756         }
 757         if (!i->procname)
 758                 return -EINVAL;
 759
 760         hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table);
 761         if (hdr == NULL)
 762                 return -ENOMEM;
 763
 764         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
 765                 unregister_sysctl_table(hdr);
 766                 return -ENOMEM;
 767         }
 768
 769         return 0;
 770 }
 771
 772 __initcall(sysctl_ipv4_init);