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 <linux/swap.h>
  18 #include <net/snmp.h>
  19 #include <net/icmp.h>
  20 #include <net/ip.h>
  21 #include <net/route.h>
  22 #include <net/tcp.h>
  23 #include <net/udp.h>
  24 #include <net/cipso_ipv4.h>
  25 #include <net/inet_frag.h>
  26 #include <net/ping.h>
  27 #include <net/tcp_memcontrol.h>
  28
  29 static int zero;
  30 static int one = 1;
  31 static int four = 4;
  32 static int gso_max_segs = GSO_MAX_SEGS;
  33 static int tcp_retr1_max = 255;
  34 static int ip_local_port_range_min[] = { 1, 1 };
  35 static int ip_local_port_range_max[] = { 65535, 65535 };
  36 static int tcp_adv_win_scale_min = -31;
  37 static int tcp_adv_win_scale_max = 31;
  38 static int ip_ttl_min = 1;
  39 static int ip_ttl_max = 255;
  40 static int tcp_syn_retries_min = 1;
  41 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
  42 static int ip_ping_group_range_min[] = { 0, 0 };
  43 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
  44
  45 /* Update system visible IP port range */
  46 static void set_local_port_range(struct net *net, int range[2])
  47 {
  48         write_seqlock(&net->ipv4.ip_local_ports.lock);
  49         net->ipv4.ip_local_ports.range[0] = range[0];
  50         net->ipv4.ip_local_ports.range[1] = range[1];
  51         write_sequnlock(&net->ipv4.ip_local_ports.lock);
  52 }
  53
  54 /* Validate changes from /proc interface. */
  55 static int ipv4_local_port_range(struct ctl_table *table, int write,
  56                                  void __user *buffer,
  57                                  size_t *lenp, loff_t *ppos)
  58 {
  59         struct net *net =
  60                 container_of(table->data, struct net, ipv4.ip_local_ports.range);
  61         int ret;
  62         int range[2];
  63         struct ctl_table tmp = {
  64                 .data = &range,
  65                 .maxlen = sizeof(range),
  66                 .mode = table->mode,
  67                 .extra1 = &ip_local_port_range_min,
  68                 .extra2 = &ip_local_port_range_max,
  69         };
  70
  71         inet_get_local_port_range(net, &range[0], &range[1]);
  72
  73         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
  74
  75         if (write && ret == 0) {
  76                 if (range[1] < range[0])
  77                         ret = -EINVAL;
  78                 else
  79                         set_local_port_range(net, range);
  80         }
  81
  82         return ret;
  83 }
  84
  85
  86 static void inet_get_ping_group_range_table(struct ctl_table *table, kgid_t *low, kgid_t *high)
  87 {
  88         kgid_t *data = table->data;
  89         struct net *net =
  90                 container_of(table->data, struct net, ipv4.ping_group_range.range);
  91         unsigned int seq;
  92         do {
  93                 seq = read_seqbegin(&net->ipv4.ip_local_ports.lock);
  94
  95                 *low = data[0];
  96                 *high = data[1];
  97         } while (read_seqretry(&net->ipv4.ip_local_ports.lock, seq));
  98 }
  99
 100 /* Update system visible IP port range */
 101 static void set_ping_group_range(struct ctl_table *table, kgid_t low, kgid_t high)
 102 {
 103         kgid_t *data = table->data;
 104         struct net *net =
 105                 container_of(table->data, struct net, ipv4.ping_group_range.range);
 106         write_seqlock(&net->ipv4.ip_local_ports.lock);
 107         data[0] = low;
 108         data[1] = high;
 109         write_sequnlock(&net->ipv4.ip_local_ports.lock);
 110 }
 111
 112 /* Validate changes from /proc interface. */
 113 static int ipv4_ping_group_range(struct ctl_table *table, int write,
 114                                  void __user *buffer,
 115                                  size_t *lenp, loff_t *ppos)
 116 {
 117         struct user_namespace *user_ns = current_user_ns();
 118         int ret;
 119         gid_t urange[2];
 120         kgid_t low, high;
 121         struct ctl_table tmp = {
 122                 .data = &urange,
 123                 .maxlen = sizeof(urange),
 124                 .mode = table->mode,
 125                 .extra1 = &ip_ping_group_range_min,
 126                 .extra2 = &ip_ping_group_range_max,
 127         };
 128
 129         inet_get_ping_group_range_table(table, &low, &high);
 130         urange[0] = from_kgid_munged(user_ns, low);
 131         urange[1] = from_kgid_munged(user_ns, high);
 132         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 133
 134         if (write && ret == 0) {
 135                 low = make_kgid(user_ns, urange[0]);
 136                 high = make_kgid(user_ns, urange[1]);
 137                 if (!gid_valid(low) || !gid_valid(high) ||
 138                     (urange[1] < urange[0]) || gid_lt(high, low)) {
 139                         low = make_kgid(&init_user_ns, 1);
 140                         high = make_kgid(&init_user_ns, 0);
 141                 }
 142                 set_ping_group_range(table, low, high);
 143         }
 144
 145         return ret;
 146 }
 147
 148 static int proc_tcp_congestion_control(struct ctl_table *ctl, int write,
 149                                        void __user *buffer, size_t *lenp, loff_t *ppos)
 150 {
 151         char val[TCP_CA_NAME_MAX];
 152         struct ctl_table tbl = {
 153                 .data = val,
 154                 .maxlen = TCP_CA_NAME_MAX,
 155         };
 156         int ret;
 157
 158         tcp_get_default_congestion_control(val);
 159
 160         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 161         if (write && ret == 0)
 162                 ret = tcp_set_default_congestion_control(val);
 163         return ret;
 164 }
 165
 166 static int proc_tcp_available_congestion_control(struct ctl_table *ctl,
 167                                                  int write,
 168                                                  void __user *buffer, size_t *lenp,
 169                                                  loff_t *ppos)
 170 {
 171         struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
 172         int ret;
 173
 174         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 175         if (!tbl.data)
 176                 return -ENOMEM;
 177         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
 178         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 179         kfree(tbl.data);
 180         return ret;
 181 }
 182
 183 static int proc_allowed_congestion_control(struct ctl_table *ctl,
 184                                            int write,
 185                                            void __user *buffer, size_t *lenp,
 186                                            loff_t *ppos)
 187 {
 188         struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 189         int ret;
 190
 191         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 192         if (!tbl.data)
 193                 return -ENOMEM;
 194
 195         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
 196         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 197         if (write && ret == 0)
 198                 ret = tcp_set_allowed_congestion_control(tbl.data);
 199         kfree(tbl.data);
 200         return ret;
 201 }
 202
 203 static int proc_tcp_fastopen_key(struct ctl_table *ctl, int write,
 204                                  void __user *buffer, size_t *lenp,
 205                                  loff_t *ppos)
 206 {
 207         struct ctl_table tbl = { .maxlen = (TCP_FASTOPEN_KEY_LENGTH * 2 + 10) };
 208         struct tcp_fastopen_context *ctxt;
 209         int ret;
 210         u32  user_key[4]; /* 16 bytes, matching TCP_FASTOPEN_KEY_LENGTH */
 211
 212         tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
 213         if (!tbl.data)
 214                 return -ENOMEM;
 215
 216         rcu_read_lock();
 217         ctxt = rcu_dereference(tcp_fastopen_ctx);
 218         if (ctxt)
 219                 memcpy(user_key, ctxt->key, TCP_FASTOPEN_KEY_LENGTH);
 220         else
 221                 memset(user_key, 0, sizeof(user_key));
 222         rcu_read_unlock();
 223
 224         snprintf(tbl.data, tbl.maxlen, "%08x-%08x-%08x-%08x",
 225                 user_key[0], user_key[1], user_key[2], user_key[3]);
 226         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 227
 228         if (write && ret == 0) {
 229                 if (sscanf(tbl.data, "%x-%x-%x-%x", user_key, user_key + 1,
 230                            user_key + 2, user_key + 3) != 4) {
 231                         ret = -EINVAL;
 232                         goto bad_key;
 233                 }
 234                 /* Generate a dummy secret but don't publish it. This
 235                  * is needed so we don't regenerate a new key on the
 236                  * first invocation of tcp_fastopen_cookie_gen
 237                  */
 238                 tcp_fastopen_init_key_once(false);
 239                 tcp_fastopen_reset_cipher(user_key, TCP_FASTOPEN_KEY_LENGTH);
 240         }
 241
 242 bad_key:
 243         pr_debug("proc FO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
 244                user_key[0], user_key[1], user_key[2], user_key[3],
 245                (char *)tbl.data, ret);
 246         kfree(tbl.data);
 247         return ret;
 248 }
 249
 250 static struct ctl_table ipv4_table[] = {
 251         {
 252                 .procname       = "tcp_timestamps",
 253                 .data           = &sysctl_tcp_timestamps,
 254                 .maxlen         = sizeof(int),
 255                 .mode           = 0644,
 256                 .proc_handler   = proc_dointvec
 257         },
 258         {
 259                 .procname       = "tcp_window_scaling",
 260                 .data           = &sysctl_tcp_window_scaling,
 261                 .maxlen         = sizeof(int),
 262                 .mode           = 0644,
 263                 .proc_handler   = proc_dointvec
 264         },
 265         {
 266                 .procname       = "tcp_sack",
 267                 .data           = &sysctl_tcp_sack,
 268                 .maxlen         = sizeof(int),
 269                 .mode           = 0644,
 270                 .proc_handler   = proc_dointvec
 271         },
 272         {
 273                 .procname       = "tcp_retrans_collapse",
 274                 .data           = &sysctl_tcp_retrans_collapse,
 275                 .maxlen         = sizeof(int),
 276                 .mode           = 0644,
 277                 .proc_handler   = proc_dointvec
 278         },
 279         {
 280                 .procname       = "ip_default_ttl",
 281                 .data           = &sysctl_ip_default_ttl,
 282                 .maxlen         = sizeof(int),
 283                 .mode           = 0644,
 284                 .proc_handler   = proc_dointvec_minmax,
 285                 .extra1         = &ip_ttl_min,
 286                 .extra2         = &ip_ttl_max,
 287         },
 288         {
 289                 .procname       = "tcp_syn_retries",
 290                 .data           = &sysctl_tcp_syn_retries,
 291                 .maxlen         = sizeof(int),
 292                 .mode           = 0644,
 293                 .proc_handler   = proc_dointvec_minmax,
 294                 .extra1         = &tcp_syn_retries_min,
 295                 .extra2         = &tcp_syn_retries_max
 296         },
 297         {
 298                 .procname       = "tcp_synack_retries",
 299                 .data           = &sysctl_tcp_synack_retries,
 300                 .maxlen         = sizeof(int),
 301                 .mode           = 0644,
 302                 .proc_handler   = proc_dointvec
 303         },
 304         {
 305                 .procname       = "tcp_max_orphans",
 306                 .data           = &sysctl_tcp_max_orphans,
 307                 .maxlen         = sizeof(int),
 308                 .mode           = 0644,
 309                 .proc_handler   = proc_dointvec
 310         },
 311         {
 312                 .procname       = "tcp_max_tw_buckets",
 313                 .data           = &tcp_death_row.sysctl_max_tw_buckets,
 314                 .maxlen         = sizeof(int),
 315                 .mode           = 0644,
 316                 .proc_handler   = proc_dointvec
 317         },
 318         {
 319                 .procname       = "ip_early_demux",
 320                 .data           = &sysctl_ip_early_demux,
 321                 .maxlen         = sizeof(int),
 322                 .mode           = 0644,
 323                 .proc_handler   = proc_dointvec
 324         },
 325         {
 326                 .procname       = "ip_dynaddr",
 327                 .data           = &sysctl_ip_dynaddr,
 328                 .maxlen         = sizeof(int),
 329                 .mode           = 0644,
 330                 .proc_handler   = proc_dointvec
 331         },
 332         {
 333                 .procname       = "tcp_keepalive_time",
 334                 .data           = &sysctl_tcp_keepalive_time,
 335                 .maxlen         = sizeof(int),
 336                 .mode           = 0644,
 337                 .proc_handler   = proc_dointvec_jiffies,
 338         },
 339         {
 340                 .procname       = "tcp_keepalive_probes",
 341                 .data           = &sysctl_tcp_keepalive_probes,
 342                 .maxlen         = sizeof(int),
 343                 .mode           = 0644,
 344                 .proc_handler   = proc_dointvec
 345         },
 346         {
 347                 .procname       = "tcp_keepalive_intvl",
 348                 .data           = &sysctl_tcp_keepalive_intvl,
 349                 .maxlen         = sizeof(int),
 350                 .mode           = 0644,
 351                 .proc_handler   = proc_dointvec_jiffies,
 352         },
 353         {
 354                 .procname       = "tcp_retries1",
 355                 .data           = &sysctl_tcp_retries1,
 356                 .maxlen         = sizeof(int),
 357                 .mode           = 0644,
 358                 .proc_handler   = proc_dointvec_minmax,
 359                 .extra2         = &tcp_retr1_max
 360         },
 361         {
 362                 .procname       = "tcp_retries2",
 363                 .data           = &sysctl_tcp_retries2,
 364                 .maxlen         = sizeof(int),
 365                 .mode           = 0644,
 366                 .proc_handler   = proc_dointvec
 367         },
 368         {
 369                 .procname       = "tcp_fin_timeout",
 370                 .data           = &sysctl_tcp_fin_timeout,
 371                 .maxlen         = sizeof(int),
 372                 .mode           = 0644,
 373                 .proc_handler   = proc_dointvec_jiffies,
 374         },
 375 #ifdef CONFIG_SYN_COOKIES
 376         {
 377                 .procname       = "tcp_syncookies",
 378                 .data           = &sysctl_tcp_syncookies,
 379                 .maxlen         = sizeof(int),
 380                 .mode           = 0644,
 381                 .proc_handler   = proc_dointvec
 382         },
 383 #endif
 384         {
 385                 .procname       = "tcp_fastopen",
 386                 .data           = &sysctl_tcp_fastopen,
 387                 .maxlen         = sizeof(int),
 388                 .mode           = 0644,
 389                 .proc_handler   = proc_dointvec,
 390         },
 391         {
 392                 .procname       = "tcp_fastopen_key",
 393                 .mode           = 0600,
 394                 .maxlen         = ((TCP_FASTOPEN_KEY_LENGTH * 2) + 10),
 395                 .proc_handler   = proc_tcp_fastopen_key,
 396         },
 397         {
 398                 .procname       = "tcp_tw_recycle",
 399                 .data           = &tcp_death_row.sysctl_tw_recycle,
 400                 .maxlen         = sizeof(int),
 401                 .mode           = 0644,
 402                 .proc_handler   = proc_dointvec
 403         },
 404         {
 405                 .procname       = "tcp_abort_on_overflow",
 406                 .data           = &sysctl_tcp_abort_on_overflow,
 407                 .maxlen         = sizeof(int),
 408                 .mode           = 0644,
 409                 .proc_handler   = proc_dointvec
 410         },
 411         {
 412                 .procname       = "tcp_stdurg",
 413                 .data           = &sysctl_tcp_stdurg,
 414                 .maxlen         = sizeof(int),
 415                 .mode           = 0644,
 416                 .proc_handler   = proc_dointvec
 417         },
 418         {
 419                 .procname       = "tcp_rfc1337",
 420                 .data           = &sysctl_tcp_rfc1337,
 421                 .maxlen         = sizeof(int),
 422                 .mode           = 0644,
 423                 .proc_handler   = proc_dointvec
 424         },
 425         {
 426                 .procname       = "tcp_max_syn_backlog",
 427                 .data           = &sysctl_max_syn_backlog,
 428                 .maxlen         = sizeof(int),
 429                 .mode           = 0644,
 430                 .proc_handler   = proc_dointvec
 431         },
 432         {
 433                 .procname       = "igmp_max_memberships",
 434                 .data           = &sysctl_igmp_max_memberships,
 435                 .maxlen         = sizeof(int),
 436                 .mode           = 0644,
 437                 .proc_handler   = proc_dointvec
 438         },
 439         {
 440                 .procname       = "igmp_max_msf",
 441                 .data           = &sysctl_igmp_max_msf,
 442                 .maxlen         = sizeof(int),
 443                 .mode           = 0644,
 444                 .proc_handler   = proc_dointvec
 445         },
 446 #ifdef CONFIG_IP_MULTICAST
 447         {
 448                 .procname       = "igmp_qrv",
 449                 .data           = &sysctl_igmp_qrv,
 450                 .maxlen         = sizeof(int),
 451                 .mode           = 0644,
 452                 .proc_handler   = proc_dointvec_minmax,
 453                 .extra1         = &one
 454         },
 455 #endif
 456         {
 457                 .procname       = "inet_peer_threshold",
 458                 .data           = &inet_peer_threshold,
 459                 .maxlen         = sizeof(int),
 460                 .mode           = 0644,
 461                 .proc_handler   = proc_dointvec
 462         },
 463         {
 464                 .procname       = "inet_peer_minttl",
 465                 .data           = &inet_peer_minttl,
 466                 .maxlen         = sizeof(int),
 467                 .mode           = 0644,
 468                 .proc_handler   = proc_dointvec_jiffies,
 469         },
 470         {
 471                 .procname       = "inet_peer_maxttl",
 472                 .data           = &inet_peer_maxttl,
 473                 .maxlen         = sizeof(int),
 474                 .mode           = 0644,
 475                 .proc_handler   = proc_dointvec_jiffies,
 476         },
 477         {
 478                 .procname       = "tcp_orphan_retries",
 479                 .data           = &sysctl_tcp_orphan_retries,
 480                 .maxlen         = sizeof(int),
 481                 .mode           = 0644,
 482                 .proc_handler   = proc_dointvec
 483         },
 484         {
 485                 .procname       = "tcp_fack",
 486                 .data           = &sysctl_tcp_fack,
 487                 .maxlen         = sizeof(int),
 488                 .mode           = 0644,
 489                 .proc_handler   = proc_dointvec
 490         },
 491         {
 492                 .procname       = "tcp_reordering",
 493                 .data           = &sysctl_tcp_reordering,
 494                 .maxlen         = sizeof(int),
 495                 .mode           = 0644,
 496                 .proc_handler   = proc_dointvec
 497         },
 498         {
 499                 .procname       = "tcp_dsack",
 500                 .data           = &sysctl_tcp_dsack,
 501                 .maxlen         = sizeof(int),
 502                 .mode           = 0644,
 503                 .proc_handler   = proc_dointvec
 504         },
 505         {
 506                 .procname       = "tcp_mem",
 507                 .maxlen         = sizeof(sysctl_tcp_mem),
 508                 .data           = &sysctl_tcp_mem,
 509                 .mode           = 0644,
 510                 .proc_handler   = proc_doulongvec_minmax,
 511         },
 512         {
 513                 .procname       = "tcp_wmem",
 514                 .data           = &sysctl_tcp_wmem,
 515                 .maxlen         = sizeof(sysctl_tcp_wmem),
 516                 .mode           = 0644,
 517                 .proc_handler   = proc_dointvec_minmax,
 518                 .extra1         = &one,
 519         },
 520         {
 521                 .procname       = "tcp_notsent_lowat",
 522                 .data           = &sysctl_tcp_notsent_lowat,
 523                 .maxlen         = sizeof(sysctl_tcp_notsent_lowat),
 524                 .mode           = 0644,
 525                 .proc_handler   = proc_dointvec,
 526         },
 527         {
 528                 .procname       = "tcp_rmem",
 529                 .data           = &sysctl_tcp_rmem,
 530                 .maxlen         = sizeof(sysctl_tcp_rmem),
 531                 .mode           = 0644,
 532                 .proc_handler   = proc_dointvec_minmax,
 533                 .extra1         = &one,
 534         },
 535         {
 536                 .procname       = "tcp_app_win",
 537                 .data           = &sysctl_tcp_app_win,
 538                 .maxlen         = sizeof(int),
 539                 .mode           = 0644,
 540                 .proc_handler   = proc_dointvec
 541         },
 542         {
 543                 .procname       = "tcp_adv_win_scale",
 544                 .data           = &sysctl_tcp_adv_win_scale,
 545                 .maxlen         = sizeof(int),
 546                 .mode           = 0644,
 547                 .proc_handler   = proc_dointvec_minmax,
 548                 .extra1         = &tcp_adv_win_scale_min,
 549                 .extra2         = &tcp_adv_win_scale_max,
 550         },
 551         {
 552                 .procname       = "tcp_tw_reuse",
 553                 .data           = &sysctl_tcp_tw_reuse,
 554                 .maxlen         = sizeof(int),
 555                 .mode           = 0644,
 556                 .proc_handler   = proc_dointvec
 557         },
 558         {
 559                 .procname       = "tcp_frto",
 560                 .data           = &sysctl_tcp_frto,
 561                 .maxlen         = sizeof(int),
 562                 .mode           = 0644,
 563                 .proc_handler   = proc_dointvec
 564         },
 565         {
 566                 .procname       = "tcp_low_latency",
 567                 .data           = &sysctl_tcp_low_latency,
 568                 .maxlen         = sizeof(int),
 569                 .mode           = 0644,
 570                 .proc_handler   = proc_dointvec
 571         },
 572         {
 573                 .procname       = "tcp_no_metrics_save",
 574                 .data           = &sysctl_tcp_nometrics_save,
 575                 .maxlen         = sizeof(int),
 576                 .mode           = 0644,
 577                 .proc_handler   = proc_dointvec,
 578         },
 579         {
 580                 .procname       = "tcp_moderate_rcvbuf",
 581                 .data           = &sysctl_tcp_moderate_rcvbuf,
 582                 .maxlen         = sizeof(int),
 583                 .mode           = 0644,
 584                 .proc_handler   = proc_dointvec,
 585         },
 586         {
 587                 .procname       = "tcp_tso_win_divisor",
 588                 .data           = &sysctl_tcp_tso_win_divisor,
 589                 .maxlen         = sizeof(int),
 590                 .mode           = 0644,
 591                 .proc_handler   = proc_dointvec,
 592         },
 593         {
 594                 .procname       = "tcp_congestion_control",
 595                 .mode           = 0644,
 596                 .maxlen         = TCP_CA_NAME_MAX,
 597                 .proc_handler   = proc_tcp_congestion_control,
 598         },
 599         {
 600                 .procname       = "tcp_mtu_probing",
 601                 .data           = &sysctl_tcp_mtu_probing,
 602                 .maxlen         = sizeof(int),
 603                 .mode           = 0644,
 604                 .proc_handler   = proc_dointvec,
 605         },
 606         {
 607                 .procname       = "tcp_base_mss",
 608                 .data           = &sysctl_tcp_base_mss,
 609                 .maxlen         = sizeof(int),
 610                 .mode           = 0644,
 611                 .proc_handler   = proc_dointvec,
 612         },
 613         {
 614                 .procname       = "tcp_workaround_signed_windows",
 615                 .data           = &sysctl_tcp_workaround_signed_windows,
 616                 .maxlen         = sizeof(int),
 617                 .mode           = 0644,
 618                 .proc_handler   = proc_dointvec
 619         },
 620         {
 621                 .procname       = "tcp_limit_output_bytes",
 622                 .data           = &sysctl_tcp_limit_output_bytes,
 623                 .maxlen         = sizeof(int),
 624                 .mode           = 0644,
 625                 .proc_handler   = proc_dointvec
 626         },
 627         {
 628                 .procname       = "tcp_challenge_ack_limit",
 629                 .data           = &sysctl_tcp_challenge_ack_limit,
 630                 .maxlen         = sizeof(int),
 631                 .mode           = 0644,
 632                 .proc_handler   = proc_dointvec
 633         },
 634         {
 635                 .procname       = "tcp_slow_start_after_idle",
 636                 .data           = &sysctl_tcp_slow_start_after_idle,
 637                 .maxlen         = sizeof(int),
 638                 .mode           = 0644,
 639                 .proc_handler   = proc_dointvec
 640         },
 641 #ifdef CONFIG_NETLABEL
 642         {
 643                 .procname       = "cipso_cache_enable",
 644                 .data           = &cipso_v4_cache_enabled,
 645                 .maxlen         = sizeof(int),
 646                 .mode           = 0644,
 647                 .proc_handler   = proc_dointvec,
 648         },
 649         {
 650                 .procname       = "cipso_cache_bucket_size",
 651                 .data           = &cipso_v4_cache_bucketsize,
 652                 .maxlen         = sizeof(int),
 653                 .mode           = 0644,
 654                 .proc_handler   = proc_dointvec,
 655         },
 656         {
 657                 .procname       = "cipso_rbm_optfmt",
 658                 .data           = &cipso_v4_rbm_optfmt,
 659                 .maxlen         = sizeof(int),
 660                 .mode           = 0644,
 661                 .proc_handler   = proc_dointvec,
 662         },
 663         {
 664                 .procname       = "cipso_rbm_strictvalid",
 665                 .data           = &cipso_v4_rbm_strictvalid,
 666                 .maxlen         = sizeof(int),
 667                 .mode           = 0644,
 668                 .proc_handler   = proc_dointvec,
 669         },
 670 #endif /* CONFIG_NETLABEL */
 671         {
 672                 .procname       = "tcp_available_congestion_control",
 673                 .maxlen         = TCP_CA_BUF_MAX,
 674                 .mode           = 0444,
 675                 .proc_handler   = proc_tcp_available_congestion_control,
 676         },
 677         {
 678                 .procname       = "tcp_allowed_congestion_control",
 679                 .maxlen         = TCP_CA_BUF_MAX,
 680                 .mode           = 0644,
 681                 .proc_handler   = proc_allowed_congestion_control,
 682         },
 683         {
 684                 .procname       = "tcp_thin_linear_timeouts",
 685                 .data           = &sysctl_tcp_thin_linear_timeouts,
 686                 .maxlen         = sizeof(int),
 687                 .mode           = 0644,
 688                 .proc_handler   = proc_dointvec
 689         },
 690         {
 691                 .procname       = "tcp_thin_dupack",
 692                 .data           = &sysctl_tcp_thin_dupack,
 693                 .maxlen         = sizeof(int),
 694                 .mode           = 0644,
 695                 .proc_handler   = proc_dointvec
 696         },
 697         {
 698                 .procname       = "tcp_early_retrans",
 699                 .data           = &sysctl_tcp_early_retrans,
 700                 .maxlen         = sizeof(int),
 701                 .mode           = 0644,
 702                 .proc_handler   = proc_dointvec_minmax,
 703                 .extra1         = &zero,
 704                 .extra2         = &four,
 705         },
 706         {
 707                 .procname       = "tcp_min_tso_segs",
 708                 .data           = &sysctl_tcp_min_tso_segs,
 709                 .maxlen         = sizeof(int),
 710                 .mode           = 0644,
 711                 .proc_handler   = proc_dointvec_minmax,
 712                 .extra1         = &zero,
 713                 .extra2         = &gso_max_segs,
 714         },
 715         {
 716                 .procname       = "tcp_autocorking",
 717                 .data           = &sysctl_tcp_autocorking,
 718                 .maxlen         = sizeof(int),
 719                 .mode           = 0644,
 720                 .proc_handler   = proc_dointvec_minmax,
 721                 .extra1         = &zero,
 722                 .extra2         = &one,
 723         },
 724         {
 725                 .procname       = "icmp_msgs_per_sec",
 726                 .data           = &sysctl_icmp_msgs_per_sec,
 727                 .maxlen         = sizeof(int),
 728                 .mode           = 0644,
 729                 .proc_handler   = proc_dointvec_minmax,
 730                 .extra1         = &zero,
 731         },
 732         {
 733                 .procname       = "icmp_msgs_burst",
 734                 .data           = &sysctl_icmp_msgs_burst,
 735                 .maxlen         = sizeof(int),
 736                 .mode           = 0644,
 737                 .proc_handler   = proc_dointvec_minmax,
 738                 .extra1         = &zero,
 739         },
 740         {
 741                 .procname       = "udp_mem",
 742                 .data           = &sysctl_udp_mem,
 743                 .maxlen         = sizeof(sysctl_udp_mem),
 744                 .mode           = 0644,
 745                 .proc_handler   = proc_doulongvec_minmax,
 746         },
 747         {
 748                 .procname       = "udp_rmem_min",
 749                 .data           = &sysctl_udp_rmem_min,
 750                 .maxlen         = sizeof(sysctl_udp_rmem_min),
 751                 .mode           = 0644,
 752                 .proc_handler   = proc_dointvec_minmax,
 753                 .extra1         = &one
 754         },
 755         {
 756                 .procname       = "udp_wmem_min",
 757                 .data           = &sysctl_udp_wmem_min,
 758                 .maxlen         = sizeof(sysctl_udp_wmem_min),
 759                 .mode           = 0644,
 760                 .proc_handler   = proc_dointvec_minmax,
 761                 .extra1         = &one
 762         },
 763         { }
 764 };
 765
 766 static struct ctl_table ipv4_net_table[] = {
 767         {
 768                 .procname       = "icmp_echo_ignore_all",
 769                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
 770                 .maxlen         = sizeof(int),
 771                 .mode           = 0644,
 772                 .proc_handler   = proc_dointvec
 773         },
 774         {
 775                 .procname       = "icmp_echo_ignore_broadcasts",
 776                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
 777                 .maxlen         = sizeof(int),
 778                 .mode           = 0644,
 779                 .proc_handler   = proc_dointvec
 780         },
 781         {
 782                 .procname       = "icmp_ignore_bogus_error_responses",
 783                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
 784                 .maxlen         = sizeof(int),
 785                 .mode           = 0644,
 786                 .proc_handler   = proc_dointvec
 787         },
 788         {
 789                 .procname       = "icmp_errors_use_inbound_ifaddr",
 790                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
 791                 .maxlen         = sizeof(int),
 792                 .mode           = 0644,
 793                 .proc_handler   = proc_dointvec
 794         },
 795         {
 796                 .procname       = "icmp_ratelimit",
 797                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
 798                 .maxlen         = sizeof(int),
 799                 .mode           = 0644,
 800                 .proc_handler   = proc_dointvec_ms_jiffies,
 801         },
 802         {
 803                 .procname       = "icmp_ratemask",
 804                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
 805                 .maxlen         = sizeof(int),
 806                 .mode           = 0644,
 807                 .proc_handler   = proc_dointvec
 808         },
 809         {
 810                 .procname       = "ping_group_range",
 811                 .data           = &init_net.ipv4.ping_group_range.range,
 812                 .maxlen         = sizeof(gid_t)*2,
 813                 .mode           = 0644,
 814                 .proc_handler   = ipv4_ping_group_range,
 815         },
 816         {
 817                 .procname       = "tcp_ecn",
 818                 .data           = &init_net.ipv4.sysctl_tcp_ecn,
 819                 .maxlen         = sizeof(int),
 820                 .mode           = 0644,
 821                 .proc_handler   = proc_dointvec
 822         },
 823         {
 824                 .procname       = "ip_local_port_range",
 825                 .maxlen         = sizeof(init_net.ipv4.ip_local_ports.range),
 826                 .data           = &init_net.ipv4.ip_local_ports.range,
 827                 .mode           = 0644,
 828                 .proc_handler   = ipv4_local_port_range,
 829         },
 830         {
 831                 .procname       = "ip_local_reserved_ports",
 832                 .data           = &init_net.ipv4.sysctl_local_reserved_ports,
 833                 .maxlen         = 65536,
 834                 .mode           = 0644,
 835                 .proc_handler   = proc_do_large_bitmap,
 836         },
 837         {
 838                 .procname       = "ip_no_pmtu_disc",
 839                 .data           = &init_net.ipv4.sysctl_ip_no_pmtu_disc,
 840                 .maxlen         = sizeof(int),
 841                 .mode           = 0644,
 842                 .proc_handler   = proc_dointvec
 843         },
 844         {
 845                 .procname       = "ip_forward_use_pmtu",
 846                 .data           = &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
 847                 .maxlen         = sizeof(int),
 848                 .mode           = 0644,
 849                 .proc_handler   = proc_dointvec,
 850         },
 851         {
 852                 .procname       = "ip_nonlocal_bind",
 853                 .data           = &init_net.ipv4.sysctl_ip_nonlocal_bind,
 854                 .maxlen         = sizeof(int),
 855                 .mode           = 0644,
 856                 .proc_handler   = proc_dointvec
 857         },
 858         {
 859                 .procname       = "fwmark_reflect",
 860                 .data           = &init_net.ipv4.sysctl_fwmark_reflect,
 861                 .maxlen         = sizeof(int),
 862                 .mode           = 0644,
 863                 .proc_handler   = proc_dointvec,
 864         },
 865         {
 866                 .procname       = "tcp_fwmark_accept",
 867                 .data           = &init_net.ipv4.sysctl_tcp_fwmark_accept,
 868                 .maxlen         = sizeof(int),
 869                 .mode           = 0644,
 870                 .proc_handler   = proc_dointvec,
 871         },
 872         { }
 873 };
 874
 875 static __net_init int ipv4_sysctl_init_net(struct net *net)
 876 {
 877         struct ctl_table *table;
 878
 879         table = ipv4_net_table;
 880         if (!net_eq(net, &init_net)) {
 881                 int i;
 882
 883                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
 884                 if (table == NULL)
 885                         goto err_alloc;
 886
 887                 /* Update the variables to point into the current struct net */
 888                 for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++)
 889                         table[i].data += (void *)net - (void *)&init_net;
 890         }
 891
 892         net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
 893         if (net->ipv4.ipv4_hdr == NULL)
 894                 goto err_reg;
 895
 896         net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
 897         if (!net->ipv4.sysctl_local_reserved_ports)
 898                 goto err_ports;
 899
 900         return 0;
 901
 902 err_ports:
 903         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
 904 err_reg:
 905         if (!net_eq(net, &init_net))
 906                 kfree(table);
 907 err_alloc:
 908         return -ENOMEM;
 909 }
 910
 911 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
 912 {
 913         struct ctl_table *table;
 914
 915         kfree(net->ipv4.sysctl_local_reserved_ports);
 916         table = net->ipv4.ipv4_hdr->ctl_table_arg;
 917         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
 918         kfree(table);
 919 }
 920
 921 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
 922         .init = ipv4_sysctl_init_net,
 923         .exit = ipv4_sysctl_exit_net,
 924 };
 925
 926 static __init int sysctl_ipv4_init(void)
 927 {
 928         struct ctl_table_header *hdr;
 929
 930         hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
 931         if (hdr == NULL)
 932                 return -ENOMEM;
 933
 934         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
 935                 unregister_net_sysctl_table(hdr);
 936                 return -ENOMEM;
 937         }
 938
 939         return 0;
 940 }
 941
 942 __initcall(sysctl_ipv4_init);