kernel/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 thousand = 1000;
  33 static int gso_max_segs = GSO_MAX_SEGS;
  34 static int tcp_retr1_max = 255;
  35 static int ip_local_port_range_min[] = { 1, 1 };
  36 static int ip_local_port_range_max[] = { 65535, 65535 };
  37 static int tcp_adv_win_scale_min = -31;
  38 static int tcp_adv_win_scale_max = 31;
  39 static int ip_ttl_min = 1;
  40 static int ip_ttl_max = 255;
  41 static int tcp_syn_retries_min = 1;
  42 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
  43 static int ip_ping_group_range_min[] = { 0, 0 };
  44 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
  45
  46 /* Update system visible IP port range */
  47 static void set_local_port_range(struct net *net, int range[2])
  48 {
  49         bool same_parity = !((range[0] ^ range[1]) & 1);
  50
  51         write_seqlock_bh(&net->ipv4.ip_local_ports.lock);
  52         if (same_parity && !net->ipv4.ip_local_ports.warned) {
  53                 net->ipv4.ip_local_ports.warned = true;
  54                 pr_err_ratelimited("ip_local_port_range: prefer different parity for start/end values.\n");
  55         }
  56         net->ipv4.ip_local_ports.range[0] = range[0];
  57         net->ipv4.ip_local_ports.range[1] = range[1];
  58         write_sequnlock_bh(&net->ipv4.ip_local_ports.lock);
  59 }
  60
  61 /* Validate changes from /proc interface. */
  62 static int ipv4_local_port_range(struct ctl_table *table, int write,
  63                                  void __user *buffer,
  64                                  size_t *lenp, loff_t *ppos)
  65 {
  66         struct net *net =
  67                 container_of(table->data, struct net, ipv4.ip_local_ports.range);
  68         int ret;
  69         int range[2];
  70         struct ctl_table tmp = {
  71                 .data = &range,
  72                 .maxlen = sizeof(range),
  73                 .mode = table->mode,
  74                 .extra1 = &ip_local_port_range_min,
  75                 .extra2 = &ip_local_port_range_max,
  76         };
  77
  78         inet_get_local_port_range(net, &range[0], &range[1]);
  79
  80         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
  81
  82         if (write && ret == 0) {
  83                 if (range[1] < range[0])
  84                         ret = -EINVAL;
  85                 else
  86                         set_local_port_range(net, range);
  87         }
  88
  89         return ret;
  90 }
  91
  92
  93 static void inet_get_ping_group_range_table(struct ctl_table *table, kgid_t *low, kgid_t *high)
  94 {
  95         kgid_t *data = table->data;
  96         struct net *net =
  97                 container_of(table->data, struct net, ipv4.ping_group_range.range);
  98         unsigned int seq;
  99         do {
 100                 seq = read_seqbegin(&net->ipv4.ip_local_ports.lock);
 101
 102                 *low = data[0];
 103                 *high = data[1];
 104         } while (read_seqretry(&net->ipv4.ip_local_ports.lock, seq));
 105 }
 106
 107 /* Update system visible IP port range */
 108 static void set_ping_group_range(struct ctl_table *table, kgid_t low, kgid_t high)
 109 {
 110         kgid_t *data = table->data;
 111         struct net *net =
 112                 container_of(table->data, struct net, ipv4.ping_group_range.range);
 113         write_seqlock(&net->ipv4.ip_local_ports.lock);
 114         data[0] = low;
 115         data[1] = high;
 116         write_sequnlock(&net->ipv4.ip_local_ports.lock);
 117 }
 118
 119 /* Validate changes from /proc interface. */
 120 static int ipv4_ping_group_range(struct ctl_table *table, int write,
 121                                  void __user *buffer,
 122                                  size_t *lenp, loff_t *ppos)
 123 {
 124         struct user_namespace *user_ns = current_user_ns();
 125         int ret;
 126         gid_t urange[2];
 127         kgid_t low, high;
 128         struct ctl_table tmp = {
 129                 .data = &urange,
 130                 .maxlen = sizeof(urange),
 131                 .mode = table->mode,
 132                 .extra1 = &ip_ping_group_range_min,
 133                 .extra2 = &ip_ping_group_range_max,
 134         };
 135
 136         inet_get_ping_group_range_table(table, &low, &high);
 137         urange[0] = from_kgid_munged(user_ns, low);
 138         urange[1] = from_kgid_munged(user_ns, high);
 139         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 140
 141         if (write && ret == 0) {
 142                 low = make_kgid(user_ns, urange[0]);
 143                 high = make_kgid(user_ns, urange[1]);
 144                 if (!gid_valid(low) || !gid_valid(high) ||
 145                     (urange[1] < urange[0]) || gid_lt(high, low)) {
 146                         low = make_kgid(&init_user_ns, 1);
 147                         high = make_kgid(&init_user_ns, 0);
 148                 }
 149                 set_ping_group_range(table, low, high);
 150         }
 151
 152         return ret;
 153 }
 154
 155 static int proc_tcp_congestion_control(struct ctl_table *ctl, int write,
 156                                        void __user *buffer, size_t *lenp, loff_t *ppos)
 157 {
 158         char val[TCP_CA_NAME_MAX];
 159         struct ctl_table tbl = {
 160                 .data = val,
 161                 .maxlen = TCP_CA_NAME_MAX,
 162         };
 163         int ret;
 164
 165         tcp_get_default_congestion_control(val);
 166
 167         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 168         if (write && ret == 0)
 169                 ret = tcp_set_default_congestion_control(val);
 170         return ret;
 171 }
 172
 173 static int proc_tcp_available_congestion_control(struct ctl_table *ctl,
 174                                                  int write,
 175                                                  void __user *buffer, size_t *lenp,
 176                                                  loff_t *ppos)
 177 {
 178         struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
 179         int ret;
 180
 181         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 182         if (!tbl.data)
 183                 return -ENOMEM;
 184         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
 185         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 186         kfree(tbl.data);
 187         return ret;
 188 }
 189
 190 static int proc_allowed_congestion_control(struct ctl_table *ctl,
 191                                            int write,
 192                                            void __user *buffer, size_t *lenp,
 193                                            loff_t *ppos)
 194 {
 195         struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 196         int ret;
 197
 198         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 199         if (!tbl.data)
 200                 return -ENOMEM;
 201
 202         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
 203         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 204         if (write && ret == 0)
 205                 ret = tcp_set_allowed_congestion_control(tbl.data);
 206         kfree(tbl.data);
 207         return ret;
 208 }
 209
 210 static int proc_tcp_fastopen_key(struct ctl_table *ctl, int write,
 211                                  void __user *buffer, size_t *lenp,
 212                                  loff_t *ppos)
 213 {
 214         struct ctl_table tbl = { .maxlen = (TCP_FASTOPEN_KEY_LENGTH * 2 + 10) };
 215         struct tcp_fastopen_context *ctxt;
 216         int ret;
 217         u32  user_key[4]; /* 16 bytes, matching TCP_FASTOPEN_KEY_LENGTH */
 218
 219         tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
 220         if (!tbl.data)
 221                 return -ENOMEM;
 222
 223         rcu_read_lock();
 224         ctxt = rcu_dereference(tcp_fastopen_ctx);
 225         if (ctxt)
 226                 memcpy(user_key, ctxt->key, TCP_FASTOPEN_KEY_LENGTH);
 227         else
 228                 memset(user_key, 0, sizeof(user_key));
 229         rcu_read_unlock();
 230
 231         snprintf(tbl.data, tbl.maxlen, "%08x-%08x-%08x-%08x",
 232                 user_key[0], user_key[1], user_key[2], user_key[3]);
 233         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 234
 235         if (write && ret == 0) {
 236                 if (sscanf(tbl.data, "%x-%x-%x-%x", user_key, user_key + 1,
 237                            user_key + 2, user_key + 3) != 4) {
 238                         ret = -EINVAL;
 239                         goto bad_key;
 240                 }
 241                 /* Generate a dummy secret but don't publish it. This
 242                  * is needed so we don't regenerate a new key on the
 243                  * first invocation of tcp_fastopen_cookie_gen
 244                  */
 245                 tcp_fastopen_init_key_once(false);
 246                 tcp_fastopen_reset_cipher(user_key, TCP_FASTOPEN_KEY_LENGTH);
 247         }
 248
 249 bad_key:
 250         pr_debug("proc FO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
 251                user_key[0], user_key[1], user_key[2], user_key[3],
 252                (char *)tbl.data, ret);
 253         kfree(tbl.data);
 254         return ret;
 255 }
 256
 257 static struct ctl_table ipv4_table[] = {
 258         {
 259                 .procname       = "tcp_timestamps",
 260                 .data           = &sysctl_tcp_timestamps,
 261                 .maxlen         = sizeof(int),
 262                 .mode           = 0644,
 263                 .proc_handler   = proc_dointvec
 264         },
 265         {
 266                 .procname       = "tcp_window_scaling",
 267                 .data           = &sysctl_tcp_window_scaling,
 268                 .maxlen         = sizeof(int),
 269                 .mode           = 0644,
 270                 .proc_handler   = proc_dointvec
 271         },
 272         {
 273                 .procname       = "tcp_sack",
 274                 .data           = &sysctl_tcp_sack,
 275                 .maxlen         = sizeof(int),
 276                 .mode           = 0644,
 277                 .proc_handler   = proc_dointvec
 278         },
 279         {
 280                 .procname       = "tcp_retrans_collapse",
 281                 .data           = &sysctl_tcp_retrans_collapse,
 282                 .maxlen         = sizeof(int),
 283                 .mode           = 0644,
 284                 .proc_handler   = proc_dointvec
 285         },
 286         {
 287                 .procname       = "ip_default_ttl",
 288                 .data           = &sysctl_ip_default_ttl,
 289                 .maxlen         = sizeof(int),
 290                 .mode           = 0644,
 291                 .proc_handler   = proc_dointvec_minmax,
 292                 .extra1         = &ip_ttl_min,
 293                 .extra2         = &ip_ttl_max,
 294         },
 295         {
 296                 .procname       = "tcp_syn_retries",
 297                 .data           = &sysctl_tcp_syn_retries,
 298                 .maxlen         = sizeof(int),
 299                 .mode           = 0644,
 300                 .proc_handler   = proc_dointvec_minmax,
 301                 .extra1         = &tcp_syn_retries_min,
 302                 .extra2         = &tcp_syn_retries_max
 303         },
 304         {
 305                 .procname       = "tcp_synack_retries",
 306                 .data           = &sysctl_tcp_synack_retries,
 307                 .maxlen         = sizeof(int),
 308                 .mode           = 0644,
 309                 .proc_handler   = proc_dointvec
 310         },
 311         {
 312                 .procname       = "tcp_max_orphans",
 313                 .data           = &sysctl_tcp_max_orphans,
 314                 .maxlen         = sizeof(int),
 315                 .mode           = 0644,
 316                 .proc_handler   = proc_dointvec
 317         },
 318         {
 319                 .procname       = "tcp_max_tw_buckets",
 320                 .data           = &tcp_death_row.sysctl_max_tw_buckets,
 321                 .maxlen         = sizeof(int),
 322                 .mode           = 0644,
 323                 .proc_handler   = proc_dointvec
 324         },
 325         {
 326                 .procname       = "ip_early_demux",
 327                 .data           = &sysctl_ip_early_demux,
 328                 .maxlen         = sizeof(int),
 329                 .mode           = 0644,
 330                 .proc_handler   = proc_dointvec
 331         },
 332         {
 333                 .procname       = "ip_dynaddr",
 334                 .data           = &sysctl_ip_dynaddr,
 335                 .maxlen         = sizeof(int),
 336                 .mode           = 0644,
 337                 .proc_handler   = proc_dointvec
 338         },
 339         {
 340                 .procname       = "tcp_keepalive_time",
 341                 .data           = &sysctl_tcp_keepalive_time,
 342                 .maxlen         = sizeof(int),
 343                 .mode           = 0644,
 344                 .proc_handler   = proc_dointvec_jiffies,
 345         },
 346         {
 347                 .procname       = "tcp_keepalive_probes",
 348                 .data           = &sysctl_tcp_keepalive_probes,
 349                 .maxlen         = sizeof(int),
 350                 .mode           = 0644,
 351                 .proc_handler   = proc_dointvec
 352         },
 353         {
 354                 .procname       = "tcp_keepalive_intvl",
 355                 .data           = &sysctl_tcp_keepalive_intvl,
 356                 .maxlen         = sizeof(int),
 357                 .mode           = 0644,
 358                 .proc_handler   = proc_dointvec_jiffies,
 359         },
 360         {
 361                 .procname       = "tcp_retries1",
 362                 .data           = &sysctl_tcp_retries1,
 363                 .maxlen         = sizeof(int),
 364                 .mode           = 0644,
 365                 .proc_handler   = proc_dointvec_minmax,
 366                 .extra2         = &tcp_retr1_max
 367         },
 368         {
 369                 .procname       = "tcp_retries2",
 370                 .data           = &sysctl_tcp_retries2,
 371                 .maxlen         = sizeof(int),
 372                 .mode           = 0644,
 373                 .proc_handler   = proc_dointvec
 374         },
 375         {
 376                 .procname       = "tcp_fin_timeout",
 377                 .data           = &sysctl_tcp_fin_timeout,
 378                 .maxlen         = sizeof(int),
 379                 .mode           = 0644,
 380                 .proc_handler   = proc_dointvec_jiffies,
 381         },
 382 #ifdef CONFIG_SYN_COOKIES
 383         {
 384                 .procname       = "tcp_syncookies",
 385                 .data           = &sysctl_tcp_syncookies,
 386                 .maxlen         = sizeof(int),
 387                 .mode           = 0644,
 388                 .proc_handler   = proc_dointvec
 389         },
 390 #endif
 391         {
 392                 .procname       = "tcp_fastopen",
 393                 .data           = &sysctl_tcp_fastopen,
 394                 .maxlen         = sizeof(int),
 395                 .mode           = 0644,
 396                 .proc_handler   = proc_dointvec,
 397         },
 398         {
 399                 .procname       = "tcp_fastopen_key",
 400                 .mode           = 0600,
 401                 .maxlen         = ((TCP_FASTOPEN_KEY_LENGTH * 2) + 10),
 402                 .proc_handler   = proc_tcp_fastopen_key,
 403         },
 404         {
 405                 .procname       = "tcp_tw_recycle",
 406                 .data           = &tcp_death_row.sysctl_tw_recycle,
 407                 .maxlen         = sizeof(int),
 408                 .mode           = 0644,
 409                 .proc_handler   = proc_dointvec
 410         },
 411         {
 412                 .procname       = "tcp_abort_on_overflow",
 413                 .data           = &sysctl_tcp_abort_on_overflow,
 414                 .maxlen         = sizeof(int),
 415                 .mode           = 0644,
 416                 .proc_handler   = proc_dointvec
 417         },
 418         {
 419                 .procname       = "tcp_stdurg",
 420                 .data           = &sysctl_tcp_stdurg,
 421                 .maxlen         = sizeof(int),
 422                 .mode           = 0644,
 423                 .proc_handler   = proc_dointvec
 424         },
 425         {
 426                 .procname       = "tcp_rfc1337",
 427                 .data           = &sysctl_tcp_rfc1337,
 428                 .maxlen         = sizeof(int),
 429                 .mode           = 0644,
 430                 .proc_handler   = proc_dointvec
 431         },
 432         {
 433                 .procname       = "tcp_max_syn_backlog",
 434                 .data           = &sysctl_max_syn_backlog,
 435                 .maxlen         = sizeof(int),
 436                 .mode           = 0644,
 437                 .proc_handler   = proc_dointvec
 438         },
 439         {
 440                 .procname       = "igmp_max_memberships",
 441                 .data           = &sysctl_igmp_max_memberships,
 442                 .maxlen         = sizeof(int),
 443                 .mode           = 0644,
 444                 .proc_handler   = proc_dointvec
 445         },
 446         {
 447                 .procname       = "igmp_max_msf",
 448                 .data           = &sysctl_igmp_max_msf,
 449                 .maxlen         = sizeof(int),
 450                 .mode           = 0644,
 451                 .proc_handler   = proc_dointvec
 452         },
 453 #ifdef CONFIG_IP_MULTICAST
 454         {
 455                 .procname       = "igmp_qrv",
 456                 .data           = &sysctl_igmp_qrv,
 457                 .maxlen         = sizeof(int),
 458                 .mode           = 0644,
 459                 .proc_handler   = proc_dointvec_minmax,
 460                 .extra1         = &one
 461         },
 462 #endif
 463         {
 464                 .procname       = "inet_peer_threshold",
 465                 .data           = &inet_peer_threshold,
 466                 .maxlen         = sizeof(int),
 467                 .mode           = 0644,
 468                 .proc_handler   = proc_dointvec
 469         },
 470         {
 471                 .procname       = "inet_peer_minttl",
 472                 .data           = &inet_peer_minttl,
 473                 .maxlen         = sizeof(int),
 474                 .mode           = 0644,
 475                 .proc_handler   = proc_dointvec_jiffies,
 476         },
 477         {
 478                 .procname       = "inet_peer_maxttl",
 479                 .data           = &inet_peer_maxttl,
 480                 .maxlen         = sizeof(int),
 481                 .mode           = 0644,
 482                 .proc_handler   = proc_dointvec_jiffies,
 483         },
 484         {
 485                 .procname       = "tcp_orphan_retries",
 486                 .data           = &sysctl_tcp_orphan_retries,
 487                 .maxlen         = sizeof(int),
 488                 .mode           = 0644,
 489                 .proc_handler   = proc_dointvec
 490         },
 491         {
 492                 .procname       = "tcp_fack",
 493                 .data           = &sysctl_tcp_fack,
 494                 .maxlen         = sizeof(int),
 495                 .mode           = 0644,
 496                 .proc_handler   = proc_dointvec
 497         },
 498         {
 499                 .procname       = "tcp_recovery",
 500                 .data           = &sysctl_tcp_recovery,
 501                 .maxlen         = sizeof(int),
 502                 .mode           = 0644,
 503                 .proc_handler   = proc_dointvec,
 504         },
 505         {
 506                 .procname       = "tcp_reordering",
 507                 .data           = &sysctl_tcp_reordering,
 508                 .maxlen         = sizeof(int),
 509                 .mode           = 0644,
 510                 .proc_handler   = proc_dointvec
 511         },
 512         {
 513                 .procname       = "tcp_max_reordering",
 514                 .data           = &sysctl_tcp_max_reordering,
 515                 .maxlen         = sizeof(int),
 516                 .mode           = 0644,
 517                 .proc_handler   = proc_dointvec
 518         },
 519         {
 520                 .procname       = "tcp_dsack",
 521                 .data           = &sysctl_tcp_dsack,
 522                 .maxlen         = sizeof(int),
 523                 .mode           = 0644,
 524                 .proc_handler   = proc_dointvec
 525         },
 526         {
 527                 .procname       = "tcp_mem",
 528                 .maxlen         = sizeof(sysctl_tcp_mem),
 529                 .data           = &sysctl_tcp_mem,
 530                 .mode           = 0644,
 531                 .proc_handler   = proc_doulongvec_minmax,
 532         },
 533         {
 534                 .procname       = "tcp_wmem",
 535                 .data           = &sysctl_tcp_wmem,
 536                 .maxlen         = sizeof(sysctl_tcp_wmem),
 537                 .mode           = 0644,
 538                 .proc_handler   = proc_dointvec_minmax,
 539                 .extra1         = &one,
 540         },
 541         {
 542                 .procname       = "tcp_notsent_lowat",
 543                 .data           = &sysctl_tcp_notsent_lowat,
 544                 .maxlen         = sizeof(sysctl_tcp_notsent_lowat),
 545                 .mode           = 0644,
 546                 .proc_handler   = proc_dointvec,
 547         },
 548         {
 549                 .procname       = "tcp_rmem",
 550                 .data           = &sysctl_tcp_rmem,
 551                 .maxlen         = sizeof(sysctl_tcp_rmem),
 552                 .mode           = 0644,
 553                 .proc_handler   = proc_dointvec_minmax,
 554                 .extra1         = &one,
 555         },
 556         {
 557                 .procname       = "tcp_app_win",
 558                 .data           = &sysctl_tcp_app_win,
 559                 .maxlen         = sizeof(int),
 560                 .mode           = 0644,
 561                 .proc_handler   = proc_dointvec
 562         },
 563         {
 564                 .procname       = "tcp_adv_win_scale",
 565                 .data           = &sysctl_tcp_adv_win_scale,
 566                 .maxlen         = sizeof(int),
 567                 .mode           = 0644,
 568                 .proc_handler   = proc_dointvec_minmax,
 569                 .extra1         = &tcp_adv_win_scale_min,
 570                 .extra2         = &tcp_adv_win_scale_max,
 571         },
 572         {
 573                 .procname       = "tcp_tw_reuse",
 574                 .data           = &sysctl_tcp_tw_reuse,
 575                 .maxlen         = sizeof(int),
 576                 .mode           = 0644,
 577                 .proc_handler   = proc_dointvec
 578         },
 579         {
 580                 .procname       = "tcp_frto",
 581                 .data           = &sysctl_tcp_frto,
 582                 .maxlen         = sizeof(int),
 583                 .mode           = 0644,
 584                 .proc_handler   = proc_dointvec
 585         },
 586         {
 587                 .procname       = "tcp_min_rtt_wlen",
 588                 .data           = &sysctl_tcp_min_rtt_wlen,
 589                 .maxlen         = sizeof(int),
 590                 .mode           = 0644,
 591                 .proc_handler   = proc_dointvec
 592         },
 593         {
 594                 .procname       = "tcp_low_latency",
 595                 .data           = &sysctl_tcp_low_latency,
 596                 .maxlen         = sizeof(int),
 597                 .mode           = 0644,
 598                 .proc_handler   = proc_dointvec
 599         },
 600         {
 601                 .procname       = "tcp_no_metrics_save",
 602                 .data           = &sysctl_tcp_nometrics_save,
 603                 .maxlen         = sizeof(int),
 604                 .mode           = 0644,
 605                 .proc_handler   = proc_dointvec,
 606         },
 607         {
 608                 .procname       = "tcp_moderate_rcvbuf",
 609                 .data           = &sysctl_tcp_moderate_rcvbuf,
 610                 .maxlen         = sizeof(int),
 611                 .mode           = 0644,
 612                 .proc_handler   = proc_dointvec,
 613         },
 614         {
 615                 .procname       = "tcp_tso_win_divisor",
 616                 .data           = &sysctl_tcp_tso_win_divisor,
 617                 .maxlen         = sizeof(int),
 618                 .mode           = 0644,
 619                 .proc_handler   = proc_dointvec,
 620         },
 621         {
 622                 .procname       = "tcp_congestion_control",
 623                 .mode           = 0644,
 624                 .maxlen         = TCP_CA_NAME_MAX,
 625                 .proc_handler   = proc_tcp_congestion_control,
 626         },
 627         {
 628                 .procname       = "tcp_workaround_signed_windows",
 629                 .data           = &sysctl_tcp_workaround_signed_windows,
 630                 .maxlen         = sizeof(int),
 631                 .mode           = 0644,
 632                 .proc_handler   = proc_dointvec
 633         },
 634         {
 635                 .procname       = "tcp_limit_output_bytes",
 636                 .data           = &sysctl_tcp_limit_output_bytes,
 637                 .maxlen         = sizeof(int),
 638                 .mode           = 0644,
 639                 .proc_handler   = proc_dointvec
 640         },
 641         {
 642                 .procname       = "tcp_challenge_ack_limit",
 643                 .data           = &sysctl_tcp_challenge_ack_limit,
 644                 .maxlen         = sizeof(int),
 645                 .mode           = 0644,
 646                 .proc_handler   = proc_dointvec
 647         },
 648         {
 649                 .procname       = "tcp_slow_start_after_idle",
 650                 .data           = &sysctl_tcp_slow_start_after_idle,
 651                 .maxlen         = sizeof(int),
 652                 .mode           = 0644,
 653                 .proc_handler   = proc_dointvec
 654         },
 655 #ifdef CONFIG_NETLABEL
 656         {
 657                 .procname       = "cipso_cache_enable",
 658                 .data           = &cipso_v4_cache_enabled,
 659                 .maxlen         = sizeof(int),
 660                 .mode           = 0644,
 661                 .proc_handler   = proc_dointvec,
 662         },
 663         {
 664                 .procname       = "cipso_cache_bucket_size",
 665                 .data           = &cipso_v4_cache_bucketsize,
 666                 .maxlen         = sizeof(int),
 667                 .mode           = 0644,
 668                 .proc_handler   = proc_dointvec,
 669         },
 670         {
 671                 .procname       = "cipso_rbm_optfmt",
 672                 .data           = &cipso_v4_rbm_optfmt,
 673                 .maxlen         = sizeof(int),
 674                 .mode           = 0644,
 675                 .proc_handler   = proc_dointvec,
 676         },
 677         {
 678                 .procname       = "cipso_rbm_strictvalid",
 679                 .data           = &cipso_v4_rbm_strictvalid,
 680                 .maxlen         = sizeof(int),
 681                 .mode           = 0644,
 682                 .proc_handler   = proc_dointvec,
 683         },
 684 #endif /* CONFIG_NETLABEL */
 685         {
 686                 .procname       = "tcp_available_congestion_control",
 687                 .maxlen         = TCP_CA_BUF_MAX,
 688                 .mode           = 0444,
 689                 .proc_handler   = proc_tcp_available_congestion_control,
 690         },
 691         {
 692                 .procname       = "tcp_allowed_congestion_control",
 693                 .maxlen         = TCP_CA_BUF_MAX,
 694                 .mode           = 0644,
 695                 .proc_handler   = proc_allowed_congestion_control,
 696         },
 697         {
 698                 .procname       = "tcp_thin_linear_timeouts",
 699                 .data           = &sysctl_tcp_thin_linear_timeouts,
 700                 .maxlen         = sizeof(int),
 701                 .mode           = 0644,
 702                 .proc_handler   = proc_dointvec
 703         },
 704         {
 705                 .procname       = "tcp_thin_dupack",
 706                 .data           = &sysctl_tcp_thin_dupack,
 707                 .maxlen         = sizeof(int),
 708                 .mode           = 0644,
 709                 .proc_handler   = proc_dointvec
 710         },
 711         {
 712                 .procname       = "tcp_early_retrans",
 713                 .data           = &sysctl_tcp_early_retrans,
 714                 .maxlen         = sizeof(int),
 715                 .mode           = 0644,
 716                 .proc_handler   = proc_dointvec_minmax,
 717                 .extra1         = &zero,
 718                 .extra2         = &four,
 719         },
 720         {
 721                 .procname       = "tcp_min_tso_segs",
 722                 .data           = &sysctl_tcp_min_tso_segs,
 723                 .maxlen         = sizeof(int),
 724                 .mode           = 0644,
 725                 .proc_handler   = proc_dointvec_minmax,
 726                 .extra1         = &one,
 727                 .extra2         = &gso_max_segs,
 728         },
 729         {
 730                 .procname       = "tcp_pacing_ss_ratio",
 731                 .data           = &sysctl_tcp_pacing_ss_ratio,
 732                 .maxlen         = sizeof(int),
 733                 .mode           = 0644,
 734                 .proc_handler   = proc_dointvec_minmax,
 735                 .extra1         = &zero,
 736                 .extra2         = &thousand,
 737         },
 738         {
 739                 .procname       = "tcp_pacing_ca_ratio",
 740                 .data           = &sysctl_tcp_pacing_ca_ratio,
 741                 .maxlen         = sizeof(int),
 742                 .mode           = 0644,
 743                 .proc_handler   = proc_dointvec_minmax,
 744                 .extra1         = &zero,
 745                 .extra2         = &thousand,
 746         },
 747         {
 748                 .procname       = "tcp_autocorking",
 749                 .data           = &sysctl_tcp_autocorking,
 750                 .maxlen         = sizeof(int),
 751                 .mode           = 0644,
 752                 .proc_handler   = proc_dointvec_minmax,
 753                 .extra1         = &zero,
 754                 .extra2         = &one,
 755         },
 756         {
 757                 .procname       = "tcp_invalid_ratelimit",
 758                 .data           = &sysctl_tcp_invalid_ratelimit,
 759                 .maxlen         = sizeof(int),
 760                 .mode           = 0644,
 761                 .proc_handler   = proc_dointvec_ms_jiffies,
 762         },
 763         {
 764                 .procname       = "icmp_msgs_per_sec",
 765                 .data           = &sysctl_icmp_msgs_per_sec,
 766                 .maxlen         = sizeof(int),
 767                 .mode           = 0644,
 768                 .proc_handler   = proc_dointvec_minmax,
 769                 .extra1         = &zero,
 770         },
 771         {
 772                 .procname       = "icmp_msgs_burst",
 773                 .data           = &sysctl_icmp_msgs_burst,
 774                 .maxlen         = sizeof(int),
 775                 .mode           = 0644,
 776                 .proc_handler   = proc_dointvec_minmax,
 777                 .extra1         = &zero,
 778         },
 779         {
 780                 .procname       = "udp_mem",
 781                 .data           = &sysctl_udp_mem,
 782                 .maxlen         = sizeof(sysctl_udp_mem),
 783                 .mode           = 0644,
 784                 .proc_handler   = proc_doulongvec_minmax,
 785         },
 786         {
 787                 .procname       = "udp_rmem_min",
 788                 .data           = &sysctl_udp_rmem_min,
 789                 .maxlen         = sizeof(sysctl_udp_rmem_min),
 790                 .mode           = 0644,
 791                 .proc_handler   = proc_dointvec_minmax,
 792                 .extra1         = &one
 793         },
 794         {
 795                 .procname       = "udp_wmem_min",
 796                 .data           = &sysctl_udp_wmem_min,
 797                 .maxlen         = sizeof(sysctl_udp_wmem_min),
 798                 .mode           = 0644,
 799                 .proc_handler   = proc_dointvec_minmax,
 800                 .extra1         = &one
 801         },
 802         { }
 803 };
 804
 805 static struct ctl_table ipv4_net_table[] = {
 806         {
 807                 .procname       = "icmp_echo_ignore_all",
 808                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
 809                 .maxlen         = sizeof(int),
 810                 .mode           = 0644,
 811                 .proc_handler   = proc_dointvec
 812         },
 813         {
 814                 .procname       = "icmp_echo_ignore_broadcasts",
 815                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
 816                 .maxlen         = sizeof(int),
 817                 .mode           = 0644,
 818                 .proc_handler   = proc_dointvec
 819         },
 820         {
 821                 .procname       = "icmp_echo_sysrq",
 822                 .data           = &init_net.ipv4.sysctl_icmp_echo_sysrq,
 823                 .maxlen         = sizeof(int),
 824                 .mode           = 0644,
 825                 .proc_handler   = proc_dointvec
 826         },
 827         {
 828                 .procname       = "icmp_ignore_bogus_error_responses",
 829                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
 830                 .maxlen         = sizeof(int),
 831                 .mode           = 0644,
 832                 .proc_handler   = proc_dointvec
 833         },
 834         {
 835                 .procname       = "icmp_errors_use_inbound_ifaddr",
 836                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
 837                 .maxlen         = sizeof(int),
 838                 .mode           = 0644,
 839                 .proc_handler   = proc_dointvec
 840         },
 841         {
 842                 .procname       = "icmp_ratelimit",
 843                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
 844                 .maxlen         = sizeof(int),
 845                 .mode           = 0644,
 846                 .proc_handler   = proc_dointvec_ms_jiffies,
 847         },
 848         {
 849                 .procname       = "icmp_ratemask",
 850                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
 851                 .maxlen         = sizeof(int),
 852                 .mode           = 0644,
 853                 .proc_handler   = proc_dointvec
 854         },
 855         {
 856                 .procname       = "ping_group_range",
 857                 .data           = &init_net.ipv4.ping_group_range.range,
 858                 .maxlen         = sizeof(gid_t)*2,
 859                 .mode           = 0644,
 860                 .proc_handler   = ipv4_ping_group_range,
 861         },
 862         {
 863                 .procname       = "tcp_ecn",
 864                 .data           = &init_net.ipv4.sysctl_tcp_ecn,
 865                 .maxlen         = sizeof(int),
 866                 .mode           = 0644,
 867                 .proc_handler   = proc_dointvec
 868         },
 869         {
 870                 .procname       = "tcp_ecn_fallback",
 871                 .data           = &init_net.ipv4.sysctl_tcp_ecn_fallback,
 872                 .maxlen         = sizeof(int),
 873                 .mode           = 0644,
 874                 .proc_handler   = proc_dointvec
 875         },
 876         {
 877                 .procname       = "ip_local_port_range",
 878                 .maxlen         = sizeof(init_net.ipv4.ip_local_ports.range),
 879                 .data           = &init_net.ipv4.ip_local_ports.range,
 880                 .mode           = 0644,
 881                 .proc_handler   = ipv4_local_port_range,
 882         },
 883         {
 884                 .procname       = "ip_local_reserved_ports",
 885                 .data           = &init_net.ipv4.sysctl_local_reserved_ports,
 886                 .maxlen         = 65536,
 887                 .mode           = 0644,
 888                 .proc_handler   = proc_do_large_bitmap,
 889         },
 890         {
 891                 .procname       = "ip_no_pmtu_disc",
 892                 .data           = &init_net.ipv4.sysctl_ip_no_pmtu_disc,
 893                 .maxlen         = sizeof(int),
 894                 .mode           = 0644,
 895                 .proc_handler   = proc_dointvec
 896         },
 897         {
 898                 .procname       = "ip_forward_use_pmtu",
 899                 .data           = &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
 900                 .maxlen         = sizeof(int),
 901                 .mode           = 0644,
 902                 .proc_handler   = proc_dointvec,
 903         },
 904         {
 905                 .procname       = "ip_nonlocal_bind",
 906                 .data           = &init_net.ipv4.sysctl_ip_nonlocal_bind,
 907                 .maxlen         = sizeof(int),
 908                 .mode           = 0644,
 909                 .proc_handler   = proc_dointvec
 910         },
 911         {
 912                 .procname       = "fwmark_reflect",
 913                 .data           = &init_net.ipv4.sysctl_fwmark_reflect,
 914                 .maxlen         = sizeof(int),
 915                 .mode           = 0644,
 916                 .proc_handler   = proc_dointvec,
 917         },
 918         {
 919                 .procname       = "tcp_fwmark_accept",
 920                 .data           = &init_net.ipv4.sysctl_tcp_fwmark_accept,
 921                 .maxlen         = sizeof(int),
 922                 .mode           = 0644,
 923                 .proc_handler   = proc_dointvec,
 924         },
 925         {
 926                 .procname       = "tcp_mtu_probing",
 927                 .data           = &init_net.ipv4.sysctl_tcp_mtu_probing,
 928                 .maxlen         = sizeof(int),
 929                 .mode           = 0644,
 930                 .proc_handler   = proc_dointvec,
 931         },
 932         {
 933                 .procname       = "tcp_base_mss",
 934                 .data           = &init_net.ipv4.sysctl_tcp_base_mss,
 935                 .maxlen         = sizeof(int),
 936                 .mode           = 0644,
 937                 .proc_handler   = proc_dointvec,
 938         },
 939         {
 940                 .procname       = "tcp_probe_threshold",
 941                 .data           = &init_net.ipv4.sysctl_tcp_probe_threshold,
 942                 .maxlen         = sizeof(int),
 943                 .mode           = 0644,
 944                 .proc_handler   = proc_dointvec,
 945         },
 946         {
 947                 .procname       = "tcp_probe_interval",
 948                 .data           = &init_net.ipv4.sysctl_tcp_probe_interval,
 949                 .maxlen         = sizeof(int),
 950                 .mode           = 0644,
 951                 .proc_handler   = proc_dointvec,
 952         },
 953         {
 954                 .procname       = "igmp_link_local_mcast_reports",
 955                 .data           = &sysctl_igmp_llm_reports,
 956                 .maxlen         = sizeof(int),
 957                 .mode           = 0644,
 958                 .proc_handler   = proc_dointvec
 959         },
 960         { }
 961 };
 962
 963 static __net_init int ipv4_sysctl_init_net(struct net *net)
 964 {
 965         struct ctl_table *table;
 966
 967         table = ipv4_net_table;
 968         if (!net_eq(net, &init_net)) {
 969                 int i;
 970
 971                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
 972                 if (!table)
 973                         goto err_alloc;
 974
 975                 /* Update the variables to point into the current struct net */
 976                 for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++)
 977                         table[i].data += (void *)net - (void *)&init_net;
 978         }
 979
 980         net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
 981         if (!net->ipv4.ipv4_hdr)
 982                 goto err_reg;
 983
 984         net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
 985         if (!net->ipv4.sysctl_local_reserved_ports)
 986                 goto err_ports;
 987
 988         return 0;
 989
 990 err_ports:
 991         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
 992 err_reg:
 993         if (!net_eq(net, &init_net))
 994                 kfree(table);
 995 err_alloc:
 996         return -ENOMEM;
 997 }
 998
 999 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
1000 {
1001         struct ctl_table *table;
1002
1003         kfree(net->ipv4.sysctl_local_reserved_ports);
1004         table = net->ipv4.ipv4_hdr->ctl_table_arg;
1005         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1006         kfree(table);
1007 }
1008
1009 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
1010         .init = ipv4_sysctl_init_net,
1011         .exit = ipv4_sysctl_exit_net,
1012 };
1013
1014 static __init int sysctl_ipv4_init(void)
1015 {
1016         struct ctl_table_header *hdr;
1017
1018         hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
1019         if (!hdr)
1020                 return -ENOMEM;
1021
1022         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
1023                 unregister_net_sysctl_table(hdr);
1024                 return -ENOMEM;
1025         }
1026
1027         return 0;
1028 }
1029
1030 __initcall(sysctl_ipv4_init);