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
  28 static int zero;
  29 static int one = 1;
  30 static int four = 4;
  31 static int thousand = 1000;
  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_privileged_port_min;
  39 static int ip_privileged_port_max = 65535;
  40 static int ip_ttl_min = 1;
  41 static int ip_ttl_max = 255;
  42 static int tcp_syn_retries_min = 1;
  43 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
  44 static int ip_ping_group_range_min[] = { 0, 0 };
  45 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
  46
  47 /* Update system visible IP port range */
  48 static void set_local_port_range(struct net *net, int range[2])
  49 {
  50         bool same_parity = !((range[0] ^ range[1]) & 1);
  51
  52         write_seqlock_bh(&net->ipv4.ip_local_ports.lock);
  53         if (same_parity && !net->ipv4.ip_local_ports.warned) {
  54                 net->ipv4.ip_local_ports.warned = true;
  55                 pr_err_ratelimited("ip_local_port_range: prefer different parity for start/end values.\n");
  56         }
  57         net->ipv4.ip_local_ports.range[0] = range[0];
  58         net->ipv4.ip_local_ports.range[1] = range[1];
  59         write_sequnlock_bh(&net->ipv4.ip_local_ports.lock);
  60 }
  61
  62 /* Validate changes from /proc interface. */
  63 static int ipv4_local_port_range(struct ctl_table *table, int write,
  64                                  void __user *buffer,
  65                                  size_t *lenp, loff_t *ppos)
  66 {
  67         struct net *net =
  68                 container_of(table->data, struct net, ipv4.ip_local_ports.range);
  69         int ret;
  70         int range[2];
  71         struct ctl_table tmp = {
  72                 .data = &range,
  73                 .maxlen = sizeof(range),
  74                 .mode = table->mode,
  75                 .extra1 = &ip_local_port_range_min,
  76                 .extra2 = &ip_local_port_range_max,
  77         };
  78
  79         inet_get_local_port_range(net, &range[0], &range[1]);
  80
  81         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
  82
  83         if (write && ret == 0) {
  84                 /* Ensure that the upper limit is not smaller than the lower,
  85                  * and that the lower does not encroach upon the privileged
  86                  * port limit.
  87                  */
  88                 if ((range[1] < range[0]) ||
  89                     (range[0] < net->ipv4.sysctl_ip_prot_sock))
  90                         ret = -EINVAL;
  91                 else
  92                         set_local_port_range(net, range);
  93         }
  94
  95         return ret;
  96 }
  97
  98 /* Validate changes from /proc interface. */
  99 static int ipv4_privileged_ports(struct ctl_table *table, int write,
 100                                 void __user *buffer, size_t *lenp, loff_t *ppos)
 101 {
 102         struct net *net = container_of(table->data, struct net,
 103             ipv4.sysctl_ip_prot_sock);
 104         int ret;
 105         int pports;
 106         int range[2];
 107         struct ctl_table tmp = {
 108                 .data = &pports,
 109                 .maxlen = sizeof(pports),
 110                 .mode = table->mode,
 111                 .extra1 = &ip_privileged_port_min,
 112                 .extra2 = &ip_privileged_port_max,
 113         };
 114
 115         pports = net->ipv4.sysctl_ip_prot_sock;
 116
 117         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 118
 119         if (write && ret == 0) {
 120                 inet_get_local_port_range(net, &range[0], &range[1]);
 121                 /* Ensure that the local port range doesn't overlap with the
 122                  * privileged port range.
 123                  */
 124                 if (range[0] < pports)
 125                         ret = -EINVAL;
 126                 else
 127                         net->ipv4.sysctl_ip_prot_sock = pports;
 128         }
 129
 130         return ret;
 131 }
 132
 133 static void inet_get_ping_group_range_table(struct ctl_table *table, kgid_t *low, kgid_t *high)
 134 {
 135         kgid_t *data = table->data;
 136         struct net *net =
 137                 container_of(table->data, struct net, ipv4.ping_group_range.range);
 138         unsigned int seq;
 139         do {
 140                 seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
 141
 142                 *low = data[0];
 143                 *high = data[1];
 144         } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
 145 }
 146
 147 /* Update system visible IP port range */
 148 static void set_ping_group_range(struct ctl_table *table, kgid_t low, kgid_t high)
 149 {
 150         kgid_t *data = table->data;
 151         struct net *net =
 152                 container_of(table->data, struct net, ipv4.ping_group_range.range);
 153         write_seqlock(&net->ipv4.ping_group_range.lock);
 154         data[0] = low;
 155         data[1] = high;
 156         write_sequnlock(&net->ipv4.ping_group_range.lock);
 157 }
 158
 159 /* Validate changes from /proc interface. */
 160 static int ipv4_ping_group_range(struct ctl_table *table, int write,
 161                                  void __user *buffer,
 162                                  size_t *lenp, loff_t *ppos)
 163 {
 164         struct user_namespace *user_ns = current_user_ns();
 165         int ret;
 166         gid_t urange[2];
 167         kgid_t low, high;
 168         struct ctl_table tmp = {
 169                 .data = &urange,
 170                 .maxlen = sizeof(urange),
 171                 .mode = table->mode,
 172                 .extra1 = &ip_ping_group_range_min,
 173                 .extra2 = &ip_ping_group_range_max,
 174         };
 175
 176         inet_get_ping_group_range_table(table, &low, &high);
 177         urange[0] = from_kgid_munged(user_ns, low);
 178         urange[1] = from_kgid_munged(user_ns, high);
 179         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 180
 181         if (write && ret == 0) {
 182                 low = make_kgid(user_ns, urange[0]);
 183                 high = make_kgid(user_ns, urange[1]);
 184                 if (!gid_valid(low) || !gid_valid(high) ||
 185                     (urange[1] < urange[0]) || gid_lt(high, low)) {
 186                         low = make_kgid(&init_user_ns, 1);
 187                         high = make_kgid(&init_user_ns, 0);
 188                 }
 189                 set_ping_group_range(table, low, high);
 190         }
 191
 192         return ret;
 193 }
 194
 195 static int proc_tcp_congestion_control(struct ctl_table *ctl, int write,
 196                                        void __user *buffer, size_t *lenp, loff_t *ppos)
 197 {
 198         char val[TCP_CA_NAME_MAX];
 199         struct ctl_table tbl = {
 200                 .data = val,
 201                 .maxlen = TCP_CA_NAME_MAX,
 202         };
 203         int ret;
 204
 205         tcp_get_default_congestion_control(val);
 206
 207         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 208         if (write && ret == 0)
 209                 ret = tcp_set_default_congestion_control(val);
 210         return ret;
 211 }
 212
 213 static int proc_tcp_available_congestion_control(struct ctl_table *ctl,
 214                                                  int write,
 215                                                  void __user *buffer, size_t *lenp,
 216                                                  loff_t *ppos)
 217 {
 218         struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
 219         int ret;
 220
 221         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 222         if (!tbl.data)
 223                 return -ENOMEM;
 224         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
 225         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 226         kfree(tbl.data);
 227         return ret;
 228 }
 229
 230 static int proc_allowed_congestion_control(struct ctl_table *ctl,
 231                                            int write,
 232                                            void __user *buffer, size_t *lenp,
 233                                            loff_t *ppos)
 234 {
 235         struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 236         int ret;
 237
 238         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 239         if (!tbl.data)
 240                 return -ENOMEM;
 241
 242         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
 243         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 244         if (write && ret == 0)
 245                 ret = tcp_set_allowed_congestion_control(tbl.data);
 246         kfree(tbl.data);
 247         return ret;
 248 }
 249
 250 static int proc_tcp_fastopen_key(struct ctl_table *ctl, int write,
 251                                  void __user *buffer, size_t *lenp,
 252                                  loff_t *ppos)
 253 {
 254         struct ctl_table tbl = { .maxlen = (TCP_FASTOPEN_KEY_LENGTH * 2 + 10) };
 255         struct tcp_fastopen_context *ctxt;
 256         int ret;
 257         u32  user_key[4]; /* 16 bytes, matching TCP_FASTOPEN_KEY_LENGTH */
 258
 259         tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
 260         if (!tbl.data)
 261                 return -ENOMEM;
 262
 263         rcu_read_lock();
 264         ctxt = rcu_dereference(tcp_fastopen_ctx);
 265         if (ctxt)
 266                 memcpy(user_key, ctxt->key, TCP_FASTOPEN_KEY_LENGTH);
 267         else
 268                 memset(user_key, 0, sizeof(user_key));
 269         rcu_read_unlock();
 270
 271         snprintf(tbl.data, tbl.maxlen, "%08x-%08x-%08x-%08x",
 272                 user_key[0], user_key[1], user_key[2], user_key[3]);
 273         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 274
 275         if (write && ret == 0) {
 276                 if (sscanf(tbl.data, "%x-%x-%x-%x", user_key, user_key + 1,
 277                            user_key + 2, user_key + 3) != 4) {
 278                         ret = -EINVAL;
 279                         goto bad_key;
 280                 }
 281                 /* Generate a dummy secret but don't publish it. This
 282                  * is needed so we don't regenerate a new key on the
 283                  * first invocation of tcp_fastopen_cookie_gen
 284                  */
 285                 tcp_fastopen_init_key_once(false);
 286                 tcp_fastopen_reset_cipher(user_key, TCP_FASTOPEN_KEY_LENGTH);
 287         }
 288
 289 bad_key:
 290         pr_debug("proc FO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
 291                user_key[0], user_key[1], user_key[2], user_key[3],
 292                (char *)tbl.data, ret);
 293         kfree(tbl.data);
 294         return ret;
 295 }
 296
 297 static struct ctl_table ipv4_table[] = {
 298         {
 299                 .procname       = "tcp_timestamps",
 300                 .data           = &sysctl_tcp_timestamps,
 301                 .maxlen         = sizeof(int),
 302                 .mode           = 0644,
 303                 .proc_handler   = proc_dointvec
 304         },
 305         {
 306                 .procname       = "tcp_window_scaling",
 307                 .data           = &sysctl_tcp_window_scaling,
 308                 .maxlen         = sizeof(int),
 309                 .mode           = 0644,
 310                 .proc_handler   = proc_dointvec
 311         },
 312         {
 313                 .procname       = "tcp_sack",
 314                 .data           = &sysctl_tcp_sack,
 315                 .maxlen         = sizeof(int),
 316                 .mode           = 0644,
 317                 .proc_handler   = proc_dointvec
 318         },
 319         {
 320                 .procname       = "tcp_retrans_collapse",
 321                 .data           = &sysctl_tcp_retrans_collapse,
 322                 .maxlen         = sizeof(int),
 323                 .mode           = 0644,
 324                 .proc_handler   = proc_dointvec
 325         },
 326         {
 327                 .procname       = "tcp_max_orphans",
 328                 .data           = &sysctl_tcp_max_orphans,
 329                 .maxlen         = sizeof(int),
 330                 .mode           = 0644,
 331                 .proc_handler   = proc_dointvec
 332         },
 333         {
 334                 .procname       = "tcp_fastopen",
 335                 .data           = &sysctl_tcp_fastopen,
 336                 .maxlen         = sizeof(int),
 337                 .mode           = 0644,
 338                 .proc_handler   = proc_dointvec,
 339         },
 340         {
 341                 .procname       = "tcp_fastopen_key",
 342                 .mode           = 0600,
 343                 .maxlen         = ((TCP_FASTOPEN_KEY_LENGTH * 2) + 10),
 344                 .proc_handler   = proc_tcp_fastopen_key,
 345         },
 346         {
 347                 .procname       = "tcp_abort_on_overflow",
 348                 .data           = &sysctl_tcp_abort_on_overflow,
 349                 .maxlen         = sizeof(int),
 350                 .mode           = 0644,
 351                 .proc_handler   = proc_dointvec
 352         },
 353         {
 354                 .procname       = "tcp_stdurg",
 355                 .data           = &sysctl_tcp_stdurg,
 356                 .maxlen         = sizeof(int),
 357                 .mode           = 0644,
 358                 .proc_handler   = proc_dointvec
 359         },
 360         {
 361                 .procname       = "tcp_rfc1337",
 362                 .data           = &sysctl_tcp_rfc1337,
 363                 .maxlen         = sizeof(int),
 364                 .mode           = 0644,
 365                 .proc_handler   = proc_dointvec
 366         },
 367         {
 368                 .procname       = "inet_peer_threshold",
 369                 .data           = &inet_peer_threshold,
 370                 .maxlen         = sizeof(int),
 371                 .mode           = 0644,
 372                 .proc_handler   = proc_dointvec
 373         },
 374         {
 375                 .procname       = "inet_peer_minttl",
 376                 .data           = &inet_peer_minttl,
 377                 .maxlen         = sizeof(int),
 378                 .mode           = 0644,
 379                 .proc_handler   = proc_dointvec_jiffies,
 380         },
 381         {
 382                 .procname       = "inet_peer_maxttl",
 383                 .data           = &inet_peer_maxttl,
 384                 .maxlen         = sizeof(int),
 385                 .mode           = 0644,
 386                 .proc_handler   = proc_dointvec_jiffies,
 387         },
 388         {
 389                 .procname       = "tcp_fack",
 390                 .data           = &sysctl_tcp_fack,
 391                 .maxlen         = sizeof(int),
 392                 .mode           = 0644,
 393                 .proc_handler   = proc_dointvec
 394         },
 395         {
 396                 .procname       = "tcp_recovery",
 397                 .data           = &sysctl_tcp_recovery,
 398                 .maxlen         = sizeof(int),
 399                 .mode           = 0644,
 400                 .proc_handler   = proc_dointvec,
 401         },
 402         {
 403                 .procname       = "tcp_max_reordering",
 404                 .data           = &sysctl_tcp_max_reordering,
 405                 .maxlen         = sizeof(int),
 406                 .mode           = 0644,
 407                 .proc_handler   = proc_dointvec
 408         },
 409         {
 410                 .procname       = "tcp_dsack",
 411                 .data           = &sysctl_tcp_dsack,
 412                 .maxlen         = sizeof(int),
 413                 .mode           = 0644,
 414                 .proc_handler   = proc_dointvec
 415         },
 416         {
 417                 .procname       = "tcp_mem",
 418                 .maxlen         = sizeof(sysctl_tcp_mem),
 419                 .data           = &sysctl_tcp_mem,
 420                 .mode           = 0644,
 421                 .proc_handler   = proc_doulongvec_minmax,
 422         },
 423         {
 424                 .procname       = "tcp_wmem",
 425                 .data           = &sysctl_tcp_wmem,
 426                 .maxlen         = sizeof(sysctl_tcp_wmem),
 427                 .mode           = 0644,
 428                 .proc_handler   = proc_dointvec_minmax,
 429                 .extra1         = &one,
 430         },
 431         {
 432                 .procname       = "tcp_rmem",
 433                 .data           = &sysctl_tcp_rmem,
 434                 .maxlen         = sizeof(sysctl_tcp_rmem),
 435                 .mode           = 0644,
 436                 .proc_handler   = proc_dointvec_minmax,
 437                 .extra1         = &one,
 438         },
 439         {
 440                 .procname       = "tcp_app_win",
 441                 .data           = &sysctl_tcp_app_win,
 442                 .maxlen         = sizeof(int),
 443                 .mode           = 0644,
 444                 .proc_handler   = proc_dointvec
 445         },
 446         {
 447                 .procname       = "tcp_adv_win_scale",
 448                 .data           = &sysctl_tcp_adv_win_scale,
 449                 .maxlen         = sizeof(int),
 450                 .mode           = 0644,
 451                 .proc_handler   = proc_dointvec_minmax,
 452                 .extra1         = &tcp_adv_win_scale_min,
 453                 .extra2         = &tcp_adv_win_scale_max,
 454         },
 455         {
 456                 .procname       = "tcp_frto",
 457                 .data           = &sysctl_tcp_frto,
 458                 .maxlen         = sizeof(int),
 459                 .mode           = 0644,
 460                 .proc_handler   = proc_dointvec
 461         },
 462         {
 463                 .procname       = "tcp_min_rtt_wlen",
 464                 .data           = &sysctl_tcp_min_rtt_wlen,
 465                 .maxlen         = sizeof(int),
 466                 .mode           = 0644,
 467                 .proc_handler   = proc_dointvec
 468         },
 469         {
 470                 .procname       = "tcp_low_latency",
 471                 .data           = &sysctl_tcp_low_latency,
 472                 .maxlen         = sizeof(int),
 473                 .mode           = 0644,
 474                 .proc_handler   = proc_dointvec
 475         },
 476         {
 477                 .procname       = "tcp_no_metrics_save",
 478                 .data           = &sysctl_tcp_nometrics_save,
 479                 .maxlen         = sizeof(int),
 480                 .mode           = 0644,
 481                 .proc_handler   = proc_dointvec,
 482         },
 483         {
 484                 .procname       = "tcp_moderate_rcvbuf",
 485                 .data           = &sysctl_tcp_moderate_rcvbuf,
 486                 .maxlen         = sizeof(int),
 487                 .mode           = 0644,
 488                 .proc_handler   = proc_dointvec,
 489         },
 490         {
 491                 .procname       = "tcp_tso_win_divisor",
 492                 .data           = &sysctl_tcp_tso_win_divisor,
 493                 .maxlen         = sizeof(int),
 494                 .mode           = 0644,
 495                 .proc_handler   = proc_dointvec,
 496         },
 497         {
 498                 .procname       = "tcp_congestion_control",
 499                 .mode           = 0644,
 500                 .maxlen         = TCP_CA_NAME_MAX,
 501                 .proc_handler   = proc_tcp_congestion_control,
 502         },
 503         {
 504                 .procname       = "tcp_workaround_signed_windows",
 505                 .data           = &sysctl_tcp_workaround_signed_windows,
 506                 .maxlen         = sizeof(int),
 507                 .mode           = 0644,
 508                 .proc_handler   = proc_dointvec
 509         },
 510         {
 511                 .procname       = "tcp_limit_output_bytes",
 512                 .data           = &sysctl_tcp_limit_output_bytes,
 513                 .maxlen         = sizeof(int),
 514                 .mode           = 0644,
 515                 .proc_handler   = proc_dointvec
 516         },
 517         {
 518                 .procname       = "tcp_challenge_ack_limit",
 519                 .data           = &sysctl_tcp_challenge_ack_limit,
 520                 .maxlen         = sizeof(int),
 521                 .mode           = 0644,
 522                 .proc_handler   = proc_dointvec
 523         },
 524         {
 525                 .procname       = "tcp_slow_start_after_idle",
 526                 .data           = &sysctl_tcp_slow_start_after_idle,
 527                 .maxlen         = sizeof(int),
 528                 .mode           = 0644,
 529                 .proc_handler   = proc_dointvec
 530         },
 531 #ifdef CONFIG_NETLABEL
 532         {
 533                 .procname       = "cipso_cache_enable",
 534                 .data           = &cipso_v4_cache_enabled,
 535                 .maxlen         = sizeof(int),
 536                 .mode           = 0644,
 537                 .proc_handler   = proc_dointvec,
 538         },
 539         {
 540                 .procname       = "cipso_cache_bucket_size",
 541                 .data           = &cipso_v4_cache_bucketsize,
 542                 .maxlen         = sizeof(int),
 543                 .mode           = 0644,
 544                 .proc_handler   = proc_dointvec,
 545         },
 546         {
 547                 .procname       = "cipso_rbm_optfmt",
 548                 .data           = &cipso_v4_rbm_optfmt,
 549                 .maxlen         = sizeof(int),
 550                 .mode           = 0644,
 551                 .proc_handler   = proc_dointvec,
 552         },
 553         {
 554                 .procname       = "cipso_rbm_strictvalid",
 555                 .data           = &cipso_v4_rbm_strictvalid,
 556                 .maxlen         = sizeof(int),
 557                 .mode           = 0644,
 558                 .proc_handler   = proc_dointvec,
 559         },
 560 #endif /* CONFIG_NETLABEL */
 561         {
 562                 .procname       = "tcp_available_congestion_control",
 563                 .maxlen         = TCP_CA_BUF_MAX,
 564                 .mode           = 0444,
 565                 .proc_handler   = proc_tcp_available_congestion_control,
 566         },
 567         {
 568                 .procname       = "tcp_allowed_congestion_control",
 569                 .maxlen         = TCP_CA_BUF_MAX,
 570                 .mode           = 0644,
 571                 .proc_handler   = proc_allowed_congestion_control,
 572         },
 573         {
 574                 .procname       = "tcp_thin_linear_timeouts",
 575                 .data           = &sysctl_tcp_thin_linear_timeouts,
 576                 .maxlen         = sizeof(int),
 577                 .mode           = 0644,
 578                 .proc_handler   = proc_dointvec
 579         },
 580         {
 581                 .procname       = "tcp_early_retrans",
 582                 .data           = &sysctl_tcp_early_retrans,
 583                 .maxlen         = sizeof(int),
 584                 .mode           = 0644,
 585                 .proc_handler   = proc_dointvec_minmax,
 586                 .extra1         = &zero,
 587                 .extra2         = &four,
 588         },
 589         {
 590                 .procname       = "tcp_min_tso_segs",
 591                 .data           = &sysctl_tcp_min_tso_segs,
 592                 .maxlen         = sizeof(int),
 593                 .mode           = 0644,
 594                 .proc_handler   = proc_dointvec_minmax,
 595                 .extra1         = &one,
 596                 .extra2         = &gso_max_segs,
 597         },
 598         {
 599                 .procname       = "tcp_pacing_ss_ratio",
 600                 .data           = &sysctl_tcp_pacing_ss_ratio,
 601                 .maxlen         = sizeof(int),
 602                 .mode           = 0644,
 603                 .proc_handler   = proc_dointvec_minmax,
 604                 .extra1         = &zero,
 605                 .extra2         = &thousand,
 606         },
 607         {
 608                 .procname       = "tcp_pacing_ca_ratio",
 609                 .data           = &sysctl_tcp_pacing_ca_ratio,
 610                 .maxlen         = sizeof(int),
 611                 .mode           = 0644,
 612                 .proc_handler   = proc_dointvec_minmax,
 613                 .extra1         = &zero,
 614                 .extra2         = &thousand,
 615         },
 616         {
 617                 .procname       = "tcp_autocorking",
 618                 .data           = &sysctl_tcp_autocorking,
 619                 .maxlen         = sizeof(int),
 620                 .mode           = 0644,
 621                 .proc_handler   = proc_dointvec_minmax,
 622                 .extra1         = &zero,
 623                 .extra2         = &one,
 624         },
 625         {
 626                 .procname       = "tcp_invalid_ratelimit",
 627                 .data           = &sysctl_tcp_invalid_ratelimit,
 628                 .maxlen         = sizeof(int),
 629                 .mode           = 0644,
 630                 .proc_handler   = proc_dointvec_ms_jiffies,
 631         },
 632         {
 633                 .procname       = "icmp_msgs_per_sec",
 634                 .data           = &sysctl_icmp_msgs_per_sec,
 635                 .maxlen         = sizeof(int),
 636                 .mode           = 0644,
 637                 .proc_handler   = proc_dointvec_minmax,
 638                 .extra1         = &zero,
 639         },
 640         {
 641                 .procname       = "icmp_msgs_burst",
 642                 .data           = &sysctl_icmp_msgs_burst,
 643                 .maxlen         = sizeof(int),
 644                 .mode           = 0644,
 645                 .proc_handler   = proc_dointvec_minmax,
 646                 .extra1         = &zero,
 647         },
 648         {
 649                 .procname       = "udp_mem",
 650                 .data           = &sysctl_udp_mem,
 651                 .maxlen         = sizeof(sysctl_udp_mem),
 652                 .mode           = 0644,
 653                 .proc_handler   = proc_doulongvec_minmax,
 654         },
 655         {
 656                 .procname       = "udp_rmem_min",
 657                 .data           = &sysctl_udp_rmem_min,
 658                 .maxlen         = sizeof(sysctl_udp_rmem_min),
 659                 .mode           = 0644,
 660                 .proc_handler   = proc_dointvec_minmax,
 661                 .extra1         = &one
 662         },
 663         {
 664                 .procname       = "udp_wmem_min",
 665                 .data           = &sysctl_udp_wmem_min,
 666                 .maxlen         = sizeof(sysctl_udp_wmem_min),
 667                 .mode           = 0644,
 668                 .proc_handler   = proc_dointvec_minmax,
 669                 .extra1         = &one
 670         },
 671         { }
 672 };
 673
 674 static struct ctl_table ipv4_net_table[] = {
 675         {
 676                 .procname       = "icmp_echo_ignore_all",
 677                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
 678                 .maxlen         = sizeof(int),
 679                 .mode           = 0644,
 680                 .proc_handler   = proc_dointvec
 681         },
 682         {
 683                 .procname       = "icmp_echo_ignore_broadcasts",
 684                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
 685                 .maxlen         = sizeof(int),
 686                 .mode           = 0644,
 687                 .proc_handler   = proc_dointvec
 688         },
 689         {
 690                 .procname       = "icmp_ignore_bogus_error_responses",
 691                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
 692                 .maxlen         = sizeof(int),
 693                 .mode           = 0644,
 694                 .proc_handler   = proc_dointvec
 695         },
 696         {
 697                 .procname       = "icmp_errors_use_inbound_ifaddr",
 698                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
 699                 .maxlen         = sizeof(int),
 700                 .mode           = 0644,
 701                 .proc_handler   = proc_dointvec
 702         },
 703         {
 704                 .procname       = "icmp_ratelimit",
 705                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
 706                 .maxlen         = sizeof(int),
 707                 .mode           = 0644,
 708                 .proc_handler   = proc_dointvec_ms_jiffies,
 709         },
 710         {
 711                 .procname       = "icmp_ratemask",
 712                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
 713                 .maxlen         = sizeof(int),
 714                 .mode           = 0644,
 715                 .proc_handler   = proc_dointvec
 716         },
 717         {
 718                 .procname       = "ping_group_range",
 719                 .data           = &init_net.ipv4.ping_group_range.range,
 720                 .maxlen         = sizeof(gid_t)*2,
 721                 .mode           = 0644,
 722                 .proc_handler   = ipv4_ping_group_range,
 723         },
 724         {
 725                 .procname       = "tcp_ecn",
 726                 .data           = &init_net.ipv4.sysctl_tcp_ecn,
 727                 .maxlen         = sizeof(int),
 728                 .mode           = 0644,
 729                 .proc_handler   = proc_dointvec
 730         },
 731         {
 732                 .procname       = "tcp_ecn_fallback",
 733                 .data           = &init_net.ipv4.sysctl_tcp_ecn_fallback,
 734                 .maxlen         = sizeof(int),
 735                 .mode           = 0644,
 736                 .proc_handler   = proc_dointvec
 737         },
 738         {
 739                 .procname       = "ip_dynaddr",
 740                 .data           = &init_net.ipv4.sysctl_ip_dynaddr,
 741                 .maxlen         = sizeof(int),
 742                 .mode           = 0644,
 743                 .proc_handler   = proc_dointvec
 744         },
 745         {
 746                 .procname       = "ip_early_demux",
 747                 .data           = &init_net.ipv4.sysctl_ip_early_demux,
 748                 .maxlen         = sizeof(int),
 749                 .mode           = 0644,
 750                 .proc_handler   = proc_dointvec
 751         },
 752         {
 753                 .procname       = "ip_default_ttl",
 754                 .data           = &init_net.ipv4.sysctl_ip_default_ttl,
 755                 .maxlen         = sizeof(int),
 756                 .mode           = 0644,
 757                 .proc_handler   = proc_dointvec_minmax,
 758                 .extra1         = &ip_ttl_min,
 759                 .extra2         = &ip_ttl_max,
 760         },
 761         {
 762                 .procname       = "ip_local_port_range",
 763                 .maxlen         = sizeof(init_net.ipv4.ip_local_ports.range),
 764                 .data           = &init_net.ipv4.ip_local_ports.range,
 765                 .mode           = 0644,
 766                 .proc_handler   = ipv4_local_port_range,
 767         },
 768         {
 769                 .procname       = "ip_local_reserved_ports",
 770                 .data           = &init_net.ipv4.sysctl_local_reserved_ports,
 771                 .maxlen         = 65536,
 772                 .mode           = 0644,
 773                 .proc_handler   = proc_do_large_bitmap,
 774         },
 775         {
 776                 .procname       = "ip_no_pmtu_disc",
 777                 .data           = &init_net.ipv4.sysctl_ip_no_pmtu_disc,
 778                 .maxlen         = sizeof(int),
 779                 .mode           = 0644,
 780                 .proc_handler   = proc_dointvec
 781         },
 782         {
 783                 .procname       = "ip_forward_use_pmtu",
 784                 .data           = &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
 785                 .maxlen         = sizeof(int),
 786                 .mode           = 0644,
 787                 .proc_handler   = proc_dointvec,
 788         },
 789         {
 790                 .procname       = "ip_nonlocal_bind",
 791                 .data           = &init_net.ipv4.sysctl_ip_nonlocal_bind,
 792                 .maxlen         = sizeof(int),
 793                 .mode           = 0644,
 794                 .proc_handler   = proc_dointvec
 795         },
 796         {
 797                 .procname       = "fwmark_reflect",
 798                 .data           = &init_net.ipv4.sysctl_fwmark_reflect,
 799                 .maxlen         = sizeof(int),
 800                 .mode           = 0644,
 801                 .proc_handler   = proc_dointvec,
 802         },
 803         {
 804                 .procname       = "tcp_fwmark_accept",
 805                 .data           = &init_net.ipv4.sysctl_tcp_fwmark_accept,
 806                 .maxlen         = sizeof(int),
 807                 .mode           = 0644,
 808                 .proc_handler   = proc_dointvec,
 809         },
 810 #ifdef CONFIG_NET_L3_MASTER_DEV
 811         {
 812                 .procname       = "tcp_l3mdev_accept",
 813                 .data           = &init_net.ipv4.sysctl_tcp_l3mdev_accept,
 814                 .maxlen         = sizeof(int),
 815                 .mode           = 0644,
 816                 .proc_handler   = proc_dointvec_minmax,
 817                 .extra1         = &zero,
 818                 .extra2         = &one,
 819         },
 820 #endif
 821         {
 822                 .procname       = "tcp_mtu_probing",
 823                 .data           = &init_net.ipv4.sysctl_tcp_mtu_probing,
 824                 .maxlen         = sizeof(int),
 825                 .mode           = 0644,
 826                 .proc_handler   = proc_dointvec,
 827         },
 828         {
 829                 .procname       = "tcp_base_mss",
 830                 .data           = &init_net.ipv4.sysctl_tcp_base_mss,
 831                 .maxlen         = sizeof(int),
 832                 .mode           = 0644,
 833                 .proc_handler   = proc_dointvec,
 834         },
 835         {
 836                 .procname       = "tcp_probe_threshold",
 837                 .data           = &init_net.ipv4.sysctl_tcp_probe_threshold,
 838                 .maxlen         = sizeof(int),
 839                 .mode           = 0644,
 840                 .proc_handler   = proc_dointvec,
 841         },
 842         {
 843                 .procname       = "tcp_probe_interval",
 844                 .data           = &init_net.ipv4.sysctl_tcp_probe_interval,
 845                 .maxlen         = sizeof(int),
 846                 .mode           = 0644,
 847                 .proc_handler   = proc_dointvec,
 848         },
 849         {
 850                 .procname       = "igmp_link_local_mcast_reports",
 851                 .data           = &init_net.ipv4.sysctl_igmp_llm_reports,
 852                 .maxlen         = sizeof(int),
 853                 .mode           = 0644,
 854                 .proc_handler   = proc_dointvec
 855         },
 856         {
 857                 .procname       = "igmp_max_memberships",
 858                 .data           = &init_net.ipv4.sysctl_igmp_max_memberships,
 859                 .maxlen         = sizeof(int),
 860                 .mode           = 0644,
 861                 .proc_handler   = proc_dointvec
 862         },
 863         {
 864                 .procname       = "igmp_max_msf",
 865                 .data           = &init_net.ipv4.sysctl_igmp_max_msf,
 866                 .maxlen         = sizeof(int),
 867                 .mode           = 0644,
 868                 .proc_handler   = proc_dointvec
 869         },
 870 #ifdef CONFIG_IP_MULTICAST
 871         {
 872                 .procname       = "igmp_qrv",
 873                 .data           = &init_net.ipv4.sysctl_igmp_qrv,
 874                 .maxlen         = sizeof(int),
 875                 .mode           = 0644,
 876                 .proc_handler   = proc_dointvec_minmax,
 877                 .extra1         = &one
 878         },
 879 #endif
 880         {
 881                 .procname       = "tcp_keepalive_time",
 882                 .data           = &init_net.ipv4.sysctl_tcp_keepalive_time,
 883                 .maxlen         = sizeof(int),
 884                 .mode           = 0644,
 885                 .proc_handler   = proc_dointvec_jiffies,
 886         },
 887         {
 888                 .procname       = "tcp_keepalive_probes",
 889                 .data           = &init_net.ipv4.sysctl_tcp_keepalive_probes,
 890                 .maxlen         = sizeof(int),
 891                 .mode           = 0644,
 892                 .proc_handler   = proc_dointvec
 893         },
 894         {
 895                 .procname       = "tcp_keepalive_intvl",
 896                 .data           = &init_net.ipv4.sysctl_tcp_keepalive_intvl,
 897                 .maxlen         = sizeof(int),
 898                 .mode           = 0644,
 899                 .proc_handler   = proc_dointvec_jiffies,
 900         },
 901         {
 902                 .procname       = "tcp_syn_retries",
 903                 .data           = &init_net.ipv4.sysctl_tcp_syn_retries,
 904                 .maxlen         = sizeof(int),
 905                 .mode           = 0644,
 906                 .proc_handler   = proc_dointvec_minmax,
 907                 .extra1         = &tcp_syn_retries_min,
 908                 .extra2         = &tcp_syn_retries_max
 909         },
 910         {
 911                 .procname       = "tcp_synack_retries",
 912                 .data           = &init_net.ipv4.sysctl_tcp_synack_retries,
 913                 .maxlen         = sizeof(int),
 914                 .mode           = 0644,
 915                 .proc_handler   = proc_dointvec
 916         },
 917 #ifdef CONFIG_SYN_COOKIES
 918         {
 919                 .procname       = "tcp_syncookies",
 920                 .data           = &init_net.ipv4.sysctl_tcp_syncookies,
 921                 .maxlen         = sizeof(int),
 922                 .mode           = 0644,
 923                 .proc_handler   = proc_dointvec
 924         },
 925 #endif
 926         {
 927                 .procname       = "tcp_reordering",
 928                 .data           = &init_net.ipv4.sysctl_tcp_reordering,
 929                 .maxlen         = sizeof(int),
 930                 .mode           = 0644,
 931                 .proc_handler   = proc_dointvec
 932         },
 933         {
 934                 .procname       = "tcp_retries1",
 935                 .data           = &init_net.ipv4.sysctl_tcp_retries1,
 936                 .maxlen         = sizeof(int),
 937                 .mode           = 0644,
 938                 .proc_handler   = proc_dointvec_minmax,
 939                 .extra2         = &tcp_retr1_max
 940         },
 941         {
 942                 .procname       = "tcp_retries2",
 943                 .data           = &init_net.ipv4.sysctl_tcp_retries2,
 944                 .maxlen         = sizeof(int),
 945                 .mode           = 0644,
 946                 .proc_handler   = proc_dointvec
 947         },
 948         {
 949                 .procname       = "tcp_orphan_retries",
 950                 .data           = &init_net.ipv4.sysctl_tcp_orphan_retries,
 951                 .maxlen         = sizeof(int),
 952                 .mode           = 0644,
 953                 .proc_handler   = proc_dointvec
 954         },
 955         {
 956                 .procname       = "tcp_fin_timeout",
 957                 .data           = &init_net.ipv4.sysctl_tcp_fin_timeout,
 958                 .maxlen         = sizeof(int),
 959                 .mode           = 0644,
 960                 .proc_handler   = proc_dointvec_jiffies,
 961         },
 962         {
 963                 .procname       = "tcp_notsent_lowat",
 964                 .data           = &init_net.ipv4.sysctl_tcp_notsent_lowat,
 965                 .maxlen         = sizeof(unsigned int),
 966                 .mode           = 0644,
 967                 .proc_handler   = proc_douintvec,
 968         },
 969         {
 970                 .procname       = "tcp_tw_reuse",
 971                 .data           = &init_net.ipv4.sysctl_tcp_tw_reuse,
 972                 .maxlen         = sizeof(int),
 973                 .mode           = 0644,
 974                 .proc_handler   = proc_dointvec
 975         },
 976         {
 977                 .procname       = "tcp_max_tw_buckets",
 978                 .data           = &init_net.ipv4.tcp_death_row.sysctl_max_tw_buckets,
 979                 .maxlen         = sizeof(int),
 980                 .mode           = 0644,
 981                 .proc_handler   = proc_dointvec
 982         },
 983         {
 984                 .procname       = "tcp_tw_recycle",
 985                 .data           = &init_net.ipv4.tcp_death_row.sysctl_tw_recycle,
 986                 .maxlen         = sizeof(int),
 987                 .mode           = 0644,
 988                 .proc_handler   = proc_dointvec
 989         },
 990         {
 991                 .procname       = "tcp_max_syn_backlog",
 992                 .data           = &init_net.ipv4.sysctl_max_syn_backlog,
 993                 .maxlen         = sizeof(int),
 994                 .mode           = 0644,
 995                 .proc_handler   = proc_dointvec
 996         },
 997 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 998         {
 999                 .procname       = "fib_multipath_use_neigh",
1000                 .data           = &init_net.ipv4.sysctl_fib_multipath_use_neigh,
1001                 .maxlen         = sizeof(int),
1002                 .mode           = 0644,
1003                 .proc_handler   = proc_dointvec_minmax,
1004                 .extra1         = &zero,
1005                 .extra2         = &one,
1006         },
1007 #endif
1008         {
1009                 .procname       = "ip_unprivileged_port_start",
1010                 .maxlen         = sizeof(int),
1011                 .data           = &init_net.ipv4.sysctl_ip_prot_sock,
1012                 .mode           = 0644,
1013                 .proc_handler   = ipv4_privileged_ports,
1014         },
1015 #ifdef CONFIG_NET_L3_MASTER_DEV
1016         {
1017                 .procname       = "udp_l3mdev_accept",
1018                 .data           = &init_net.ipv4.sysctl_udp_l3mdev_accept,
1019                 .maxlen         = sizeof(int),
1020                 .mode           = 0644,
1021                 .proc_handler   = proc_dointvec_minmax,
1022                 .extra1         = &zero,
1023                 .extra2         = &one,
1024         },
1025 #endif
1026         { }
1027 };
1028
1029 static __net_init int ipv4_sysctl_init_net(struct net *net)
1030 {
1031         struct ctl_table *table;
1032
1033         table = ipv4_net_table;
1034         if (!net_eq(net, &init_net)) {
1035                 int i;
1036
1037                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
1038                 if (!table)
1039                         goto err_alloc;
1040
1041                 /* Update the variables to point into the current struct net */
1042                 for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++)
1043                         table[i].data += (void *)net - (void *)&init_net;
1044         }
1045
1046         net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
1047         if (!net->ipv4.ipv4_hdr)
1048                 goto err_reg;
1049
1050         net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1051         if (!net->ipv4.sysctl_local_reserved_ports)
1052                 goto err_ports;
1053
1054         return 0;
1055
1056 err_ports:
1057         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1058 err_reg:
1059         if (!net_eq(net, &init_net))
1060                 kfree(table);
1061 err_alloc:
1062         return -ENOMEM;
1063 }
1064
1065 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
1066 {
1067         struct ctl_table *table;
1068
1069         kfree(net->ipv4.sysctl_local_reserved_ports);
1070         table = net->ipv4.ipv4_hdr->ctl_table_arg;
1071         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1072         kfree(table);
1073 }
1074
1075 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
1076         .init = ipv4_sysctl_init_net,
1077         .exit = ipv4_sysctl_exit_net,
1078 };
1079
1080 static __init int sysctl_ipv4_init(void)
1081 {
1082         struct ctl_table_header *hdr;
1083
1084         hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
1085         if (!hdr)
1086                 return -ENOMEM;
1087
1088         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
1089                 unregister_net_sysctl_table(hdr);
1090                 return -ENOMEM;
1091         }
1092
1093         return 0;
1094 }
1095
1096 __initcall(sysctl_ipv4_init);