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 one = 1;
  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_min_snd_mss_min = TCP_MIN_SND_MSS;
  33 static int tcp_min_snd_mss_max = 65535;
  34 static int tcp_adv_win_scale_max = 31;
  35 static int ip_ttl_min = 1;
  36 static int ip_ttl_max = 255;
  37 static int tcp_syn_retries_min = 1;
  38 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
  39 static int ip_ping_group_range_min[] = { 0, 0 };
  40 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
  41
  42 /* Update system visible IP port range */
  43 static void set_local_port_range(int range[2])
  44 {
  45         write_seqlock(&sysctl_local_ports.lock);
  46         sysctl_local_ports.range[0] = range[0];
  47         sysctl_local_ports.range[1] = range[1];
  48         write_sequnlock(&sysctl_local_ports.lock);
  49 }
  50
  51 /* Validate changes from /proc interface. */
  52 static int ipv4_local_port_range(ctl_table *table, int write,
  53                                  void __user *buffer,
  54                                  size_t *lenp, loff_t *ppos)
  55 {
  56         int ret;
  57         int range[2];
  58         ctl_table tmp = {
  59                 .data = &range,
  60                 .maxlen = sizeof(range),
  61                 .mode = table->mode,
  62                 .extra1 = &ip_local_port_range_min,
  63                 .extra2 = &ip_local_port_range_max,
  64         };
  65
  66         inet_get_local_port_range(range, range + 1);
  67         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
  68
  69         if (write && ret == 0) {
  70                 if (range[1] < range[0])
  71                         ret = -EINVAL;
  72                 else
  73                         set_local_port_range(range);
  74         }
  75
  76         return ret;
  77 }
  78
  79
  80 void inet_get_ping_group_range_table(struct ctl_table *table, gid_t *low, gid_t *high)
  81 {
  82         gid_t *data = table->data;
  83         unsigned seq;
  84         do {
  85                 seq = read_seqbegin(&sysctl_local_ports.lock);
  86
  87                 *low = data[0];
  88                 *high = data[1];
  89         } while (read_seqretry(&sysctl_local_ports.lock, seq));
  90 }
  91
  92 /* Update system visible IP port range */
  93 static void set_ping_group_range(struct ctl_table *table, int range[2])
  94 {
  95         gid_t *data = table->data;
  96         write_seqlock(&sysctl_local_ports.lock);
  97         data[0] = range[0];
  98         data[1] = range[1];
  99         write_sequnlock(&sysctl_local_ports.lock);
 100 }
 101
 102 /* Validate changes from /proc interface. */
 103 static int ipv4_ping_group_range(ctl_table *table, int write,
 104                                  void __user *buffer,
 105                                  size_t *lenp, loff_t *ppos)
 106 {
 107         int ret;
 108         gid_t range[2];
 109         ctl_table tmp = {
 110                 .data = &range,
 111                 .maxlen = sizeof(range),
 112                 .mode = table->mode,
 113                 .extra1 = &ip_ping_group_range_min,
 114                 .extra2 = &ip_ping_group_range_max,
 115         };
 116
 117         inet_get_ping_group_range_table(table, range, range + 1);
 118         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 119
 120         if (write && ret == 0)
 121                 set_ping_group_range(table, range);
 122
 123         return ret;
 124 }
 125
 126 static int proc_tcp_congestion_control(ctl_table *ctl, int write,
 127                                        void __user *buffer, size_t *lenp, loff_t *ppos)
 128 {
 129         char val[TCP_CA_NAME_MAX];
 130         ctl_table tbl = {
 131                 .data = val,
 132                 .maxlen = TCP_CA_NAME_MAX,
 133         };
 134         int ret;
 135
 136         tcp_get_default_congestion_control(val);
 137
 138         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 139         if (write && ret == 0)
 140                 ret = tcp_set_default_congestion_control(val);
 141         return ret;
 142 }
 143
 144 static int proc_tcp_available_congestion_control(ctl_table *ctl,
 145                                                  int write,
 146                                                  void __user *buffer, size_t *lenp,
 147                                                  loff_t *ppos)
 148 {
 149         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
 150         int ret;
 151
 152         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 153         if (!tbl.data)
 154                 return -ENOMEM;
 155         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
 156         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 157         kfree(tbl.data);
 158         return ret;
 159 }
 160
 161 static int proc_allowed_congestion_control(ctl_table *ctl,
 162                                            int write,
 163                                            void __user *buffer, size_t *lenp,
 164                                            loff_t *ppos)
 165 {
 166         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 167         int ret;
 168
 169         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 170         if (!tbl.data)
 171                 return -ENOMEM;
 172
 173         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
 174         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 175         if (write && ret == 0)
 176                 ret = tcp_set_allowed_congestion_control(tbl.data);
 177         kfree(tbl.data);
 178         return ret;
 179 }
 180
 181 static struct ctl_table ipv4_table[] = {
 182         {
 183                 .procname       = "tcp_timestamps",
 184                 .data           = &sysctl_tcp_timestamps,
 185                 .maxlen         = sizeof(int),
 186                 .mode           = 0644,
 187                 .proc_handler   = proc_dointvec
 188         },
 189         {
 190                 .procname       = "tcp_window_scaling",
 191                 .data           = &sysctl_tcp_window_scaling,
 192                 .maxlen         = sizeof(int),
 193                 .mode           = 0644,
 194                 .proc_handler   = proc_dointvec
 195         },
 196         {
 197                 .procname       = "tcp_sack",
 198                 .data           = &sysctl_tcp_sack,
 199                 .maxlen         = sizeof(int),
 200                 .mode           = 0644,
 201                 .proc_handler   = proc_dointvec
 202         },
 203         {
 204                 .procname       = "tcp_retrans_collapse",
 205                 .data           = &sysctl_tcp_retrans_collapse,
 206                 .maxlen         = sizeof(int),
 207                 .mode           = 0644,
 208                 .proc_handler   = proc_dointvec
 209         },
 210         {
 211                 .procname       = "ip_default_ttl",
 212                 .data           = &sysctl_ip_default_ttl,
 213                 .maxlen         = sizeof(int),
 214                 .mode           = 0644,
 215                 .proc_handler   = proc_dointvec_minmax,
 216                 .extra1         = &ip_ttl_min,
 217                 .extra2         = &ip_ttl_max,
 218         },
 219         {
 220                 .procname       = "ip_no_pmtu_disc",
 221                 .data           = &ipv4_config.no_pmtu_disc,
 222                 .maxlen         = sizeof(int),
 223                 .mode           = 0644,
 224                 .proc_handler   = proc_dointvec
 225         },
 226         {
 227                 .procname       = "ip_nonlocal_bind",
 228                 .data           = &sysctl_ip_nonlocal_bind,
 229                 .maxlen         = sizeof(int),
 230                 .mode           = 0644,
 231                 .proc_handler   = proc_dointvec
 232         },
 233         {
 234                 .procname       = "tcp_syn_retries",
 235                 .data           = &sysctl_tcp_syn_retries,
 236                 .maxlen         = sizeof(int),
 237                 .mode           = 0644,
 238                 .proc_handler   = proc_dointvec_minmax,
 239                 .extra1         = &tcp_syn_retries_min,
 240                 .extra2         = &tcp_syn_retries_max
 241         },
 242         {
 243                 .procname       = "tcp_synack_retries",
 244                 .data           = &sysctl_tcp_synack_retries,
 245                 .maxlen         = sizeof(int),
 246                 .mode           = 0644,
 247                 .proc_handler   = proc_dointvec
 248         },
 249         {
 250                 .procname       = "tcp_max_orphans",
 251                 .data           = &sysctl_tcp_max_orphans,
 252                 .maxlen         = sizeof(int),
 253                 .mode           = 0644,
 254                 .proc_handler   = proc_dointvec
 255         },
 256         {
 257                 .procname       = "tcp_max_tw_buckets",
 258                 .data           = &tcp_death_row.sysctl_max_tw_buckets,
 259                 .maxlen         = sizeof(int),
 260                 .mode           = 0644,
 261                 .proc_handler   = proc_dointvec
 262         },
 263         {
 264                 .procname       = "ip_dynaddr",
 265                 .data           = &sysctl_ip_dynaddr,
 266                 .maxlen         = sizeof(int),
 267                 .mode           = 0644,
 268                 .proc_handler   = proc_dointvec
 269         },
 270         {
 271                 .procname       = "tcp_keepalive_time",
 272                 .data           = &sysctl_tcp_keepalive_time,
 273                 .maxlen         = sizeof(int),
 274                 .mode           = 0644,
 275                 .proc_handler   = proc_dointvec_jiffies,
 276         },
 277         {
 278                 .procname       = "tcp_keepalive_probes",
 279                 .data           = &sysctl_tcp_keepalive_probes,
 280                 .maxlen         = sizeof(int),
 281                 .mode           = 0644,
 282                 .proc_handler   = proc_dointvec
 283         },
 284         {
 285                 .procname       = "tcp_keepalive_intvl",
 286                 .data           = &sysctl_tcp_keepalive_intvl,
 287                 .maxlen         = sizeof(int),
 288                 .mode           = 0644,
 289                 .proc_handler   = proc_dointvec_jiffies,
 290         },
 291         {
 292                 .procname       = "tcp_retries1",
 293                 .data           = &sysctl_tcp_retries1,
 294                 .maxlen         = sizeof(int),
 295                 .mode           = 0644,
 296                 .proc_handler   = proc_dointvec_minmax,
 297                 .extra2         = &tcp_retr1_max
 298         },
 299         {
 300                 .procname       = "tcp_retries2",
 301                 .data           = &sysctl_tcp_retries2,
 302                 .maxlen         = sizeof(int),
 303                 .mode           = 0644,
 304                 .proc_handler   = proc_dointvec
 305         },
 306         {
 307                 .procname       = "tcp_fin_timeout",
 308                 .data           = &sysctl_tcp_fin_timeout,
 309                 .maxlen         = sizeof(int),
 310                 .mode           = 0644,
 311                 .proc_handler   = proc_dointvec_jiffies,
 312         },
 313 #ifdef CONFIG_SYN_COOKIES
 314         {
 315                 .procname       = "tcp_syncookies",
 316                 .data           = &sysctl_tcp_syncookies,
 317                 .maxlen         = sizeof(int),
 318                 .mode           = 0644,
 319                 .proc_handler   = proc_dointvec
 320         },
 321 #endif
 322         {
 323                 .procname       = "tcp_tw_recycle",
 324                 .data           = &tcp_death_row.sysctl_tw_recycle,
 325                 .maxlen         = sizeof(int),
 326                 .mode           = 0644,
 327                 .proc_handler   = proc_dointvec
 328         },
 329         {
 330                 .procname       = "tcp_abort_on_overflow",
 331                 .data           = &sysctl_tcp_abort_on_overflow,
 332                 .maxlen         = sizeof(int),
 333                 .mode           = 0644,
 334                 .proc_handler   = proc_dointvec
 335         },
 336         {
 337                 .procname       = "tcp_stdurg",
 338                 .data           = &sysctl_tcp_stdurg,
 339                 .maxlen         = sizeof(int),
 340                 .mode           = 0644,
 341                 .proc_handler   = proc_dointvec
 342         },
 343         {
 344                 .procname       = "tcp_rfc1337",
 345                 .data           = &sysctl_tcp_rfc1337,
 346                 .maxlen         = sizeof(int),
 347                 .mode           = 0644,
 348                 .proc_handler   = proc_dointvec
 349         },
 350         {
 351                 .procname       = "tcp_max_syn_backlog",
 352                 .data           = &sysctl_max_syn_backlog,
 353                 .maxlen         = sizeof(int),
 354                 .mode           = 0644,
 355                 .proc_handler   = proc_dointvec
 356         },
 357         {
 358                 .procname       = "ip_local_port_range",
 359                 .data           = &sysctl_local_ports.range,
 360                 .maxlen         = sizeof(sysctl_local_ports.range),
 361                 .mode           = 0644,
 362                 .proc_handler   = ipv4_local_port_range,
 363         },
 364         {
 365                 .procname       = "ip_local_reserved_ports",
 366                 .data           = NULL, /* initialized in sysctl_ipv4_init */
 367                 .maxlen         = 65536,
 368                 .mode           = 0644,
 369                 .proc_handler   = proc_do_large_bitmap,
 370         },
 371         {
 372                 .procname       = "igmp_max_memberships",
 373                 .data           = &sysctl_igmp_max_memberships,
 374                 .maxlen         = sizeof(int),
 375                 .mode           = 0644,
 376                 .proc_handler   = proc_dointvec
 377         },
 378         {
 379                 .procname       = "igmp_max_msf",
 380                 .data           = &sysctl_igmp_max_msf,
 381                 .maxlen         = sizeof(int),
 382                 .mode           = 0644,
 383                 .proc_handler   = proc_dointvec
 384         },
 385         {
 386                 .procname       = "inet_peer_threshold",
 387                 .data           = &inet_peer_threshold,
 388                 .maxlen         = sizeof(int),
 389                 .mode           = 0644,
 390                 .proc_handler   = proc_dointvec
 391         },
 392         {
 393                 .procname       = "inet_peer_minttl",
 394                 .data           = &inet_peer_minttl,
 395                 .maxlen         = sizeof(int),
 396                 .mode           = 0644,
 397                 .proc_handler   = proc_dointvec_jiffies,
 398         },
 399         {
 400                 .procname       = "inet_peer_maxttl",
 401                 .data           = &inet_peer_maxttl,
 402                 .maxlen         = sizeof(int),
 403                 .mode           = 0644,
 404                 .proc_handler   = proc_dointvec_jiffies,
 405         },
 406         {
 407                 .procname       = "tcp_orphan_retries",
 408                 .data           = &sysctl_tcp_orphan_retries,
 409                 .maxlen         = sizeof(int),
 410                 .mode           = 0644,
 411                 .proc_handler   = proc_dointvec
 412         },
 413         {
 414                 .procname       = "tcp_fack",
 415                 .data           = &sysctl_tcp_fack,
 416                 .maxlen         = sizeof(int),
 417                 .mode           = 0644,
 418                 .proc_handler   = proc_dointvec
 419         },
 420         {
 421                 .procname       = "tcp_reordering",
 422                 .data           = &sysctl_tcp_reordering,
 423                 .maxlen         = sizeof(int),
 424                 .mode           = 0644,
 425                 .proc_handler   = proc_dointvec
 426         },
 427         {
 428                 .procname       = "tcp_ecn",
 429                 .data           = &sysctl_tcp_ecn,
 430                 .maxlen         = sizeof(int),
 431                 .mode           = 0644,
 432                 .proc_handler   = proc_dointvec
 433         },
 434         {
 435                 .procname       = "tcp_dsack",
 436                 .data           = &sysctl_tcp_dsack,
 437                 .maxlen         = sizeof(int),
 438                 .mode           = 0644,
 439                 .proc_handler   = proc_dointvec
 440         },
 441         {
 442                 .procname       = "tcp_mem",
 443                 .data           = &sysctl_tcp_mem,
 444                 .maxlen         = sizeof(sysctl_tcp_mem),
 445                 .mode           = 0644,
 446                 .proc_handler   = proc_doulongvec_minmax
 447         },
 448         {
 449                 .procname       = "tcp_wmem",
 450                 .data           = &sysctl_tcp_wmem,
 451                 .maxlen         = sizeof(sysctl_tcp_wmem),
 452                 .mode           = 0644,
 453                 .proc_handler   = proc_dointvec_minmax,
 454                 .extra1         = &one,
 455         },
 456         {
 457                 .procname       = "tcp_rmem",
 458                 .data           = &sysctl_tcp_rmem,
 459                 .maxlen         = sizeof(sysctl_tcp_rmem),
 460                 .mode           = 0644,
 461                 .proc_handler   = proc_dointvec_minmax,
 462                 .extra1         = &one,
 463         },
 464         {
 465                 .procname       = "tcp_app_win",
 466                 .data           = &sysctl_tcp_app_win,
 467                 .maxlen         = sizeof(int),
 468                 .mode           = 0644,
 469                 .proc_handler   = proc_dointvec
 470         },
 471         {
 472                 .procname       = "tcp_adv_win_scale",
 473                 .data           = &sysctl_tcp_adv_win_scale,
 474                 .maxlen         = sizeof(int),
 475                 .mode           = 0644,
 476                 .proc_handler   = proc_dointvec_minmax,
 477                 .extra1         = &tcp_adv_win_scale_min,
 478                 .extra2         = &tcp_adv_win_scale_max,
 479         },
 480         {
 481                 .procname       = "tcp_tw_reuse",
 482                 .data           = &sysctl_tcp_tw_reuse,
 483                 .maxlen         = sizeof(int),
 484                 .mode           = 0644,
 485                 .proc_handler   = proc_dointvec
 486         },
 487         {
 488                 .procname       = "tcp_frto",
 489                 .data           = &sysctl_tcp_frto,
 490                 .maxlen         = sizeof(int),
 491                 .mode           = 0644,
 492                 .proc_handler   = proc_dointvec
 493         },
 494         {
 495                 .procname       = "tcp_frto_response",
 496                 .data           = &sysctl_tcp_frto_response,
 497                 .maxlen         = sizeof(int),
 498                 .mode           = 0644,
 499                 .proc_handler   = proc_dointvec
 500         },
 501         {
 502                 .procname       = "tcp_low_latency",
 503                 .data           = &sysctl_tcp_low_latency,
 504                 .maxlen         = sizeof(int),
 505                 .mode           = 0644,
 506                 .proc_handler   = proc_dointvec
 507         },
 508         {
 509                 .procname       = "tcp_no_metrics_save",
 510                 .data           = &sysctl_tcp_nometrics_save,
 511                 .maxlen         = sizeof(int),
 512                 .mode           = 0644,
 513                 .proc_handler   = proc_dointvec,
 514         },
 515         {
 516                 .procname       = "tcp_moderate_rcvbuf",
 517                 .data           = &sysctl_tcp_moderate_rcvbuf,
 518                 .maxlen         = sizeof(int),
 519                 .mode           = 0644,
 520                 .proc_handler   = proc_dointvec,
 521         },
 522         {
 523                 .procname       = "tcp_tso_win_divisor",
 524                 .data           = &sysctl_tcp_tso_win_divisor,
 525                 .maxlen         = sizeof(int),
 526                 .mode           = 0644,
 527                 .proc_handler   = proc_dointvec,
 528         },
 529         {
 530                 .procname       = "tcp_congestion_control",
 531                 .mode           = 0644,
 532                 .maxlen         = TCP_CA_NAME_MAX,
 533                 .proc_handler   = proc_tcp_congestion_control,
 534         },
 535         {
 536                 .procname       = "tcp_abc",
 537                 .data           = &sysctl_tcp_abc,
 538                 .maxlen         = sizeof(int),
 539                 .mode           = 0644,
 540                 .proc_handler   = proc_dointvec,
 541         },
 542         {
 543                 .procname       = "tcp_mtu_probing",
 544                 .data           = &sysctl_tcp_mtu_probing,
 545                 .maxlen         = sizeof(int),
 546                 .mode           = 0644,
 547                 .proc_handler   = proc_dointvec,
 548         },
 549         {
 550                 .procname       = "tcp_base_mss",
 551                 .data           = &sysctl_tcp_base_mss,
 552                 .maxlen         = sizeof(int),
 553                 .mode           = 0644,
 554                 .proc_handler   = proc_dointvec,
 555         },
 556         {
 557                 .procname       = "tcp_min_snd_mss",
 558                 .data           = &sysctl_tcp_min_snd_mss,
 559                 .maxlen         = sizeof(int),
 560                 .mode           = 0644,
 561                 .proc_handler   = proc_dointvec_minmax,
 562                 .extra1         = &tcp_min_snd_mss_min,
 563                 .extra2         = &tcp_min_snd_mss_max,
 564         },
 565         {
 566                 .procname       = "tcp_workaround_signed_windows",
 567                 .data           = &sysctl_tcp_workaround_signed_windows,
 568                 .maxlen         = sizeof(int),
 569                 .mode           = 0644,
 570                 .proc_handler   = proc_dointvec
 571         },
 572         {
 573                 .procname       = "tcp_challenge_ack_limit",
 574                 .data           = &sysctl_tcp_challenge_ack_limit,
 575                 .maxlen         = sizeof(int),
 576                 .mode           = 0644,
 577                 .proc_handler   = proc_dointvec
 578         },
 579 #ifdef CONFIG_NET_DMA
 580         {
 581                 .procname       = "tcp_dma_copybreak",
 582                 .data           = &sysctl_tcp_dma_copybreak,
 583                 .maxlen         = sizeof(int),
 584                 .mode           = 0644,
 585                 .proc_handler   = proc_dointvec
 586         },
 587 #endif
 588         {
 589                 .procname       = "tcp_slow_start_after_idle",
 590                 .data           = &sysctl_tcp_slow_start_after_idle,
 591                 .maxlen         = sizeof(int),
 592                 .mode           = 0644,
 593                 .proc_handler   = proc_dointvec
 594         },
 595 #ifdef CONFIG_NETLABEL
 596         {
 597                 .procname       = "cipso_cache_enable",
 598                 .data           = &cipso_v4_cache_enabled,
 599                 .maxlen         = sizeof(int),
 600                 .mode           = 0644,
 601                 .proc_handler   = proc_dointvec,
 602         },
 603         {
 604                 .procname       = "cipso_cache_bucket_size",
 605                 .data           = &cipso_v4_cache_bucketsize,
 606                 .maxlen         = sizeof(int),
 607                 .mode           = 0644,
 608                 .proc_handler   = proc_dointvec,
 609         },
 610         {
 611                 .procname       = "cipso_rbm_optfmt",
 612                 .data           = &cipso_v4_rbm_optfmt,
 613                 .maxlen         = sizeof(int),
 614                 .mode           = 0644,
 615                 .proc_handler   = proc_dointvec,
 616         },
 617         {
 618                 .procname       = "cipso_rbm_strictvalid",
 619                 .data           = &cipso_v4_rbm_strictvalid,
 620                 .maxlen         = sizeof(int),
 621                 .mode           = 0644,
 622                 .proc_handler   = proc_dointvec,
 623         },
 624 #endif /* CONFIG_NETLABEL */
 625         {
 626                 .procname       = "tcp_available_congestion_control",
 627                 .maxlen         = TCP_CA_BUF_MAX,
 628                 .mode           = 0444,
 629                 .proc_handler   = proc_tcp_available_congestion_control,
 630         },
 631         {
 632                 .procname       = "tcp_allowed_congestion_control",
 633                 .maxlen         = TCP_CA_BUF_MAX,
 634                 .mode           = 0644,
 635                 .proc_handler   = proc_allowed_congestion_control,
 636         },
 637         {
 638                 .procname       = "tcp_max_ssthresh",
 639                 .data           = &sysctl_tcp_max_ssthresh,
 640                 .maxlen         = sizeof(int),
 641                 .mode           = 0644,
 642                 .proc_handler   = proc_dointvec,
 643         },
 644         {
 645                 .procname       = "tcp_cookie_size",
 646                 .data           = &sysctl_tcp_cookie_size,
 647                 .maxlen         = sizeof(int),
 648                 .mode           = 0644,
 649                 .proc_handler   = proc_dointvec
 650         },
 651         {
 652                 .procname       = "tcp_thin_linear_timeouts",
 653                 .data           = &sysctl_tcp_thin_linear_timeouts,
 654                 .maxlen         = sizeof(int),
 655                 .mode           = 0644,
 656                 .proc_handler   = proc_dointvec
 657         },
 658         {
 659                 .procname       = "tcp_thin_dupack",
 660                 .data           = &sysctl_tcp_thin_dupack,
 661                 .maxlen         = sizeof(int),
 662                 .mode           = 0644,
 663                 .proc_handler   = proc_dointvec
 664         },
 665         {
 666                 .procname       = "udp_mem",
 667                 .data           = &sysctl_udp_mem,
 668                 .maxlen         = sizeof(sysctl_udp_mem),
 669                 .mode           = 0644,
 670                 .proc_handler   = proc_doulongvec_minmax,
 671         },
 672         {
 673                 .procname       = "udp_rmem_min",
 674                 .data           = &sysctl_udp_rmem_min,
 675                 .maxlen         = sizeof(sysctl_udp_rmem_min),
 676                 .mode           = 0644,
 677                 .proc_handler   = proc_dointvec_minmax,
 678                 .extra1         = &one
 679         },
 680         {
 681                 .procname       = "udp_wmem_min",
 682                 .data           = &sysctl_udp_wmem_min,
 683                 .maxlen         = sizeof(sysctl_udp_wmem_min),
 684                 .mode           = 0644,
 685                 .proc_handler   = proc_dointvec_minmax,
 686                 .extra1         = &one
 687         },
 688         { }
 689 };
 690
 691 static struct ctl_table ipv4_net_table[] = {
 692         {
 693                 .procname       = "icmp_echo_ignore_all",
 694                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
 695                 .maxlen         = sizeof(int),
 696                 .mode           = 0644,
 697                 .proc_handler   = proc_dointvec
 698         },
 699         {
 700                 .procname       = "icmp_echo_ignore_broadcasts",
 701                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
 702                 .maxlen         = sizeof(int),
 703                 .mode           = 0644,
 704                 .proc_handler   = proc_dointvec
 705         },
 706         {
 707                 .procname       = "icmp_ignore_bogus_error_responses",
 708                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
 709                 .maxlen         = sizeof(int),
 710                 .mode           = 0644,
 711                 .proc_handler   = proc_dointvec
 712         },
 713         {
 714                 .procname       = "icmp_errors_use_inbound_ifaddr",
 715                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
 716                 .maxlen         = sizeof(int),
 717                 .mode           = 0644,
 718                 .proc_handler   = proc_dointvec
 719         },
 720         {
 721                 .procname       = "icmp_ratelimit",
 722                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
 723                 .maxlen         = sizeof(int),
 724                 .mode           = 0644,
 725                 .proc_handler   = proc_dointvec_ms_jiffies,
 726         },
 727         {
 728                 .procname       = "icmp_ratemask",
 729                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
 730                 .maxlen         = sizeof(int),
 731                 .mode           = 0644,
 732                 .proc_handler   = proc_dointvec
 733         },
 734         {
 735                 .procname       = "rt_cache_rebuild_count",
 736                 .data           = &init_net.ipv4.sysctl_rt_cache_rebuild_count,
 737                 .maxlen         = sizeof(int),
 738                 .mode           = 0644,
 739                 .proc_handler   = proc_dointvec
 740         },
 741         {
 742                 .procname       = "ping_group_range",
 743                 .data           = &init_net.ipv4.sysctl_ping_group_range,
 744                 .maxlen         = sizeof(init_net.ipv4.sysctl_ping_group_range),
 745                 .mode           = 0644,
 746                 .proc_handler   = ipv4_ping_group_range,
 747         },
 748         { }
 749 };
 750
 751 struct ctl_path net_ipv4_ctl_path[] = {
 752         { .procname = "net", },
 753         { .procname = "ipv4", },
 754         { },
 755 };
 756 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path);
 757
 758 static __net_init int ipv4_sysctl_init_net(struct net *net)
 759 {
 760         struct ctl_table *table;
 761
 762         table = ipv4_net_table;
 763         if (!net_eq(net, &init_net)) {
 764                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
 765                 if (table == NULL)
 766                         goto err_alloc;
 767
 768                 table[0].data =
 769                         &net->ipv4.sysctl_icmp_echo_ignore_all;
 770                 table[1].data =
 771                         &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
 772                 table[2].data =
 773                         &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
 774                 table[3].data =
 775                         &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
 776                 table[4].data =
 777                         &net->ipv4.sysctl_icmp_ratelimit;
 778                 table[5].data =
 779                         &net->ipv4.sysctl_icmp_ratemask;
 780                 table[6].data =
 781                         &net->ipv4.sysctl_rt_cache_rebuild_count;
 782                 table[7].data =
 783                         &net->ipv4.sysctl_ping_group_range;
 784
 785         }
 786
 787         /*
 788          * Sane defaults - nobody may create ping sockets.
 789          * Boot scripts should set this to distro-specific group.
 790          */
 791         net->ipv4.sysctl_ping_group_range[0] = 1;
 792         net->ipv4.sysctl_ping_group_range[1] = 0;
 793
 794         net->ipv4.sysctl_rt_cache_rebuild_count = 4;
 795
 796         net->ipv4.ipv4_hdr = register_net_sysctl_table(net,
 797                         net_ipv4_ctl_path, table);
 798         if (net->ipv4.ipv4_hdr == NULL)
 799                 goto err_reg;
 800
 801         return 0;
 802
 803 err_reg:
 804         if (!net_eq(net, &init_net))
 805                 kfree(table);
 806 err_alloc:
 807         return -ENOMEM;
 808 }
 809
 810 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
 811 {
 812         struct ctl_table *table;
 813
 814         table = net->ipv4.ipv4_hdr->ctl_table_arg;
 815         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
 816         kfree(table);
 817 }
 818
 819 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
 820         .init = ipv4_sysctl_init_net,
 821         .exit = ipv4_sysctl_exit_net,
 822 };
 823
 824 static __init int sysctl_ipv4_init(void)
 825 {
 826         struct ctl_table_header *hdr;
 827         struct ctl_table *i;
 828
 829         for (i = ipv4_table; i->procname; i++) {
 830                 if (strcmp(i->procname, "ip_local_reserved_ports") == 0) {
 831                         i->data = sysctl_local_reserved_ports;
 832                         break;
 833                 }
 834         }
 835         if (!i->procname)
 836                 return -EINVAL;
 837
 838         hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table);
 839         if (hdr == NULL)
 840                 return -ENOMEM;
 841
 842         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
 843                 unregister_sysctl_table(hdr);
 844                 return -ENOMEM;
 845         }
 846
 847         return 0;
 848 }
 849
 850 __initcall(sysctl_ipv4_init);