net/ipv4/sysctl_net_ipv4.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
   4  *
   5  * Begun April 1, 1996, Mike Shaver.
   6  * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
   7  */
   8
   9 #include <linux/mm.h>
  10 #include <linux/module.h>
  11 #include <linux/sysctl.h>
  12 #include <linux/igmp.h>
  13 #include <linux/inetdevice.h>
  14 #include <linux/seqlock.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17 #include <linux/nsproxy.h>
  18 #include <linux/swap.h>
  19 #include <net/snmp.h>
  20 #include <net/icmp.h>
  21 #include <net/ip.h>
  22 #include <net/route.h>
  23 #include <net/tcp.h>
  24 #include <net/udp.h>
  25 #include <net/cipso_ipv4.h>
  26 #include <net/inet_frag.h>
  27 #include <net/ping.h>
  28 #include <net/protocol.h>
  29 #include <net/netevent.h>
  30
  31 static int two = 2;
  32 static int four = 4;
  33 static int thousand = 1000;
  34 static int gso_max_segs = GSO_MAX_SEGS;
  35 static int tcp_retr1_max = 255;
  36 static int ip_local_port_range_min[] = { 1, 1 };
  37 static int ip_local_port_range_max[] = { 65535, 65535 };
  38 static int tcp_adv_win_scale_min = -31;
  39 static int tcp_adv_win_scale_max = 31;
  40 static int tcp_min_snd_mss_min = TCP_MIN_SND_MSS;
  41 static int tcp_min_snd_mss_max = 65535;
  42 static int ip_privileged_port_min;
  43 static int ip_privileged_port_max = 65535;
  44 static int ip_ttl_min = 1;
  45 static int ip_ttl_max = 255;
  46 static int tcp_syn_retries_min = 1;
  47 static int tcp_syn_retries_max = MAX_TCP_SYNCNT;
  48 static int ip_ping_group_range_min[] = { 0, 0 };
  49 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
  50 static int comp_sack_nr_max = 255;
  51 static u32 u32_max_div_HZ = UINT_MAX / HZ;
  52 static int one_day_secs = 24 * 3600;
  53
  54 /* obsolete */
  55 static int sysctl_tcp_low_latency __read_mostly;
  56
  57 /* Update system visible IP port range */
  58 static void set_local_port_range(struct net *net, int range[2])
  59 {
  60         bool same_parity = !((range[0] ^ range[1]) & 1);
  61
  62         write_seqlock_bh(&net->ipv4.ip_local_ports.lock);
  63         if (same_parity && !net->ipv4.ip_local_ports.warned) {
  64                 net->ipv4.ip_local_ports.warned = true;
  65                 pr_err_ratelimited("ip_local_port_range: prefer different parity for start/end values.\n");
  66         }
  67         net->ipv4.ip_local_ports.range[0] = range[0];
  68         net->ipv4.ip_local_ports.range[1] = range[1];
  69         write_sequnlock_bh(&net->ipv4.ip_local_ports.lock);
  70 }
  71
  72 /* Validate changes from /proc interface. */
  73 static int ipv4_local_port_range(struct ctl_table *table, int write,
  74                                  void __user *buffer,
  75                                  size_t *lenp, loff_t *ppos)
  76 {
  77         struct net *net =
  78                 container_of(table->data, struct net, ipv4.ip_local_ports.range);
  79         int ret;
  80         int range[2];
  81         struct ctl_table tmp = {
  82                 .data = &range,
  83                 .maxlen = sizeof(range),
  84                 .mode = table->mode,
  85                 .extra1 = &ip_local_port_range_min,
  86                 .extra2 = &ip_local_port_range_max,
  87         };
  88
  89         inet_get_local_port_range(net, &range[0], &range[1]);
  90
  91         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
  92
  93         if (write && ret == 0) {
  94                 /* Ensure that the upper limit is not smaller than the lower,
  95                  * and that the lower does not encroach upon the privileged
  96                  * port limit.
  97                  */
  98                 if ((range[1] < range[0]) ||
  99                     (range[0] < net->ipv4.sysctl_ip_prot_sock))
 100                         ret = -EINVAL;
 101                 else
 102                         set_local_port_range(net, range);
 103         }
 104
 105         return ret;
 106 }
 107
 108 /* Validate changes from /proc interface. */
 109 static int ipv4_privileged_ports(struct ctl_table *table, int write,
 110                                 void __user *buffer, size_t *lenp, loff_t *ppos)
 111 {
 112         struct net *net = container_of(table->data, struct net,
 113             ipv4.sysctl_ip_prot_sock);
 114         int ret;
 115         int pports;
 116         int range[2];
 117         struct ctl_table tmp = {
 118                 .data = &pports,
 119                 .maxlen = sizeof(pports),
 120                 .mode = table->mode,
 121                 .extra1 = &ip_privileged_port_min,
 122                 .extra2 = &ip_privileged_port_max,
 123         };
 124
 125         pports = net->ipv4.sysctl_ip_prot_sock;
 126
 127         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 128
 129         if (write && ret == 0) {
 130                 inet_get_local_port_range(net, &range[0], &range[1]);
 131                 /* Ensure that the local port range doesn't overlap with the
 132                  * privileged port range.
 133                  */
 134                 if (range[0] < pports)
 135                         ret = -EINVAL;
 136                 else
 137                         net->ipv4.sysctl_ip_prot_sock = pports;
 138         }
 139
 140         return ret;
 141 }
 142
 143 static void inet_get_ping_group_range_table(struct ctl_table *table, kgid_t *low, kgid_t *high)
 144 {
 145         kgid_t *data = table->data;
 146         struct net *net =
 147                 container_of(table->data, struct net, ipv4.ping_group_range.range);
 148         unsigned int seq;
 149         do {
 150                 seq = read_seqbegin(&net->ipv4.ping_group_range.lock);
 151
 152                 *low = data[0];
 153                 *high = data[1];
 154         } while (read_seqretry(&net->ipv4.ping_group_range.lock, seq));
 155 }
 156
 157 /* Update system visible IP port range */
 158 static void set_ping_group_range(struct ctl_table *table, kgid_t low, kgid_t high)
 159 {
 160         kgid_t *data = table->data;
 161         struct net *net =
 162                 container_of(table->data, struct net, ipv4.ping_group_range.range);
 163         write_seqlock(&net->ipv4.ping_group_range.lock);
 164         data[0] = low;
 165         data[1] = high;
 166         write_sequnlock(&net->ipv4.ping_group_range.lock);
 167 }
 168
 169 /* Validate changes from /proc interface. */
 170 static int ipv4_ping_group_range(struct ctl_table *table, int write,
 171                                  void __user *buffer,
 172                                  size_t *lenp, loff_t *ppos)
 173 {
 174         struct user_namespace *user_ns = current_user_ns();
 175         int ret;
 176         gid_t urange[2];
 177         kgid_t low, high;
 178         struct ctl_table tmp = {
 179                 .data = &urange,
 180                 .maxlen = sizeof(urange),
 181                 .mode = table->mode,
 182                 .extra1 = &ip_ping_group_range_min,
 183                 .extra2 = &ip_ping_group_range_max,
 184         };
 185
 186         inet_get_ping_group_range_table(table, &low, &high);
 187         urange[0] = from_kgid_munged(user_ns, low);
 188         urange[1] = from_kgid_munged(user_ns, high);
 189         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 190
 191         if (write && ret == 0) {
 192                 low = make_kgid(user_ns, urange[0]);
 193                 high = make_kgid(user_ns, urange[1]);
 194                 if (!gid_valid(low) || !gid_valid(high))
 195                         return -EINVAL;
 196                 if (urange[1] < urange[0] || gid_lt(high, low)) {
 197                         low = make_kgid(&init_user_ns, 1);
 198                         high = make_kgid(&init_user_ns, 0);
 199                 }
 200                 set_ping_group_range(table, low, high);
 201         }
 202
 203         return ret;
 204 }
 205
 206 static int ipv4_fwd_update_priority(struct ctl_table *table, int write,
 207                                     void __user *buffer,
 208                                     size_t *lenp, loff_t *ppos)
 209 {
 210         struct net *net;
 211         int ret;
 212
 213         net = container_of(table->data, struct net,
 214                            ipv4.sysctl_ip_fwd_update_priority);
 215         ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 216         if (write && ret == 0)
 217                 call_netevent_notifiers(NETEVENT_IPV4_FWD_UPDATE_PRIORITY_UPDATE,
 218                                         net);
 219
 220         return ret;
 221 }
 222
 223 static int proc_tcp_congestion_control(struct ctl_table *ctl, int write,
 224                                        void __user *buffer, size_t *lenp, loff_t *ppos)
 225 {
 226         struct net *net = container_of(ctl->data, struct net,
 227                                        ipv4.tcp_congestion_control);
 228         char val[TCP_CA_NAME_MAX];
 229         struct ctl_table tbl = {
 230                 .data = val,
 231                 .maxlen = TCP_CA_NAME_MAX,
 232         };
 233         int ret;
 234
 235         tcp_get_default_congestion_control(net, val);
 236
 237         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 238         if (write && ret == 0)
 239                 ret = tcp_set_default_congestion_control(net, val);
 240         return ret;
 241 }
 242
 243 static int proc_tcp_available_congestion_control(struct ctl_table *ctl,
 244                                                  int write,
 245                                                  void __user *buffer, size_t *lenp,
 246                                                  loff_t *ppos)
 247 {
 248         struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
 249         int ret;
 250
 251         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 252         if (!tbl.data)
 253                 return -ENOMEM;
 254         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
 255         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 256         kfree(tbl.data);
 257         return ret;
 258 }
 259
 260 static int proc_allowed_congestion_control(struct ctl_table *ctl,
 261                                            int write,
 262                                            void __user *buffer, size_t *lenp,
 263                                            loff_t *ppos)
 264 {
 265         struct ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 266         int ret;
 267
 268         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 269         if (!tbl.data)
 270                 return -ENOMEM;
 271
 272         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
 273         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 274         if (write && ret == 0)
 275                 ret = tcp_set_allowed_congestion_control(tbl.data);
 276         kfree(tbl.data);
 277         return ret;
 278 }
 279
 280 static int sscanf_key(char *buf, __le32 *key)
 281 {
 282         u32 user_key[4];
 283         int i, ret = 0;
 284
 285         if (sscanf(buf, "%x-%x-%x-%x", user_key, user_key + 1,
 286                    user_key + 2, user_key + 3) != 4) {
 287                 ret = -EINVAL;
 288         } else {
 289                 for (i = 0; i < ARRAY_SIZE(user_key); i++)
 290                         key[i] = cpu_to_le32(user_key[i]);
 291         }
 292         pr_debug("proc TFO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
 293                  user_key[0], user_key[1], user_key[2], user_key[3], buf, ret);
 294
 295         return ret;
 296 }
 297
 298 static int proc_tcp_fastopen_key(struct ctl_table *table, int write,
 299                                  void __user *buffer, size_t *lenp,
 300                                  loff_t *ppos)
 301 {
 302         struct net *net = container_of(table->data, struct net,
 303             ipv4.sysctl_tcp_fastopen);
 304         /* maxlen to print the list of keys in hex (*2), with dashes
 305          * separating doublewords and a comma in between keys.
 306          */
 307         struct ctl_table tbl = { .maxlen = ((TCP_FASTOPEN_KEY_LENGTH *
 308                                             2 * TCP_FASTOPEN_KEY_MAX) +
 309                                             (TCP_FASTOPEN_KEY_MAX * 5)) };
 310         struct tcp_fastopen_context *ctx;
 311         u32 user_key[TCP_FASTOPEN_KEY_MAX * 4];
 312         __le32 key[TCP_FASTOPEN_KEY_MAX * 4];
 313         char *backup_data;
 314         int ret, i = 0, off = 0, n_keys = 0;
 315
 316         tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
 317         if (!tbl.data)
 318                 return -ENOMEM;
 319
 320         rcu_read_lock();
 321         ctx = rcu_dereference(net->ipv4.tcp_fastopen_ctx);
 322         if (ctx) {
 323                 n_keys = tcp_fastopen_context_len(ctx);
 324                 memcpy(&key[0], &ctx->key[0], TCP_FASTOPEN_KEY_LENGTH * n_keys);
 325         }
 326         rcu_read_unlock();
 327
 328         if (!n_keys) {
 329                 memset(&key[0], 0, TCP_FASTOPEN_KEY_LENGTH);
 330                 n_keys = 1;
 331         }
 332
 333         for (i = 0; i < n_keys * 4; i++)
 334                 user_key[i] = le32_to_cpu(key[i]);
 335
 336         for (i = 0; i < n_keys; i++) {
 337                 off += snprintf(tbl.data + off, tbl.maxlen - off,
 338                                 "%08x-%08x-%08x-%08x",
 339                                 user_key[i * 4],
 340                                 user_key[i * 4 + 1],
 341                                 user_key[i * 4 + 2],
 342                                 user_key[i * 4 + 3]);
 343
 344                 if (WARN_ON_ONCE(off >= tbl.maxlen - 1))
 345                         break;
 346
 347                 if (i + 1 < n_keys)
 348                         off += snprintf(tbl.data + off, tbl.maxlen - off, ",");
 349         }
 350
 351         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 352
 353         if (write && ret == 0) {
 354                 backup_data = strchr(tbl.data, ',');
 355                 if (backup_data) {
 356                         *backup_data = '\0';
 357                         backup_data++;
 358                 }
 359                 if (sscanf_key(tbl.data, key)) {
 360                         ret = -EINVAL;
 361                         goto bad_key;
 362                 }
 363                 if (backup_data) {
 364                         if (sscanf_key(backup_data, key + 4)) {
 365                                 ret = -EINVAL;
 366                                 goto bad_key;
 367                         }
 368                 }
 369                 tcp_fastopen_reset_cipher(net, NULL, key,
 370                                           backup_data ? key + 4 : NULL);
 371         }
 372
 373 bad_key:
 374         kfree(tbl.data);
 375         return ret;
 376 }
 377
 378 static void proc_configure_early_demux(int enabled, int protocol)
 379 {
 380         struct net_protocol *ipprot;
 381 #if IS_ENABLED(CONFIG_IPV6)
 382         struct inet6_protocol *ip6prot;
 383 #endif
 384
 385         rcu_read_lock();
 386
 387         ipprot = rcu_dereference(inet_protos[protocol]);
 388         if (ipprot)
 389                 ipprot->early_demux = enabled ? ipprot->early_demux_handler :
 390                                                 NULL;
 391
 392 #if IS_ENABLED(CONFIG_IPV6)
 393         ip6prot = rcu_dereference(inet6_protos[protocol]);
 394         if (ip6prot)
 395                 ip6prot->early_demux = enabled ? ip6prot->early_demux_handler :
 396                                                  NULL;
 397 #endif
 398         rcu_read_unlock();
 399 }
 400
 401 static int proc_tcp_early_demux(struct ctl_table *table, int write,
 402                                 void __user *buffer, size_t *lenp, loff_t *ppos)
 403 {
 404         int ret = 0;
 405
 406         ret = proc_dointvec(table, write, buffer, lenp, ppos);
 407
 408         if (write && !ret) {
 409                 int enabled = init_net.ipv4.sysctl_tcp_early_demux;
 410
 411                 proc_configure_early_demux(enabled, IPPROTO_TCP);
 412         }
 413
 414         return ret;
 415 }
 416
 417 static int proc_udp_early_demux(struct ctl_table *table, int write,
 418                                 void __user *buffer, size_t *lenp, loff_t *ppos)
 419 {
 420         int ret = 0;
 421
 422         ret = proc_dointvec(table, write, buffer, lenp, ppos);
 423
 424         if (write && !ret) {
 425                 int enabled = init_net.ipv4.sysctl_udp_early_demux;
 426
 427                 proc_configure_early_demux(enabled, IPPROTO_UDP);
 428         }
 429
 430         return ret;
 431 }
 432
 433 static int proc_tfo_blackhole_detect_timeout(struct ctl_table *table,
 434                                              int write,
 435                                              void __user *buffer,
 436                                              size_t *lenp, loff_t *ppos)
 437 {
 438         struct net *net = container_of(table->data, struct net,
 439             ipv4.sysctl_tcp_fastopen_blackhole_timeout);
 440         int ret;
 441
 442         ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 443         if (write && ret == 0)
 444                 atomic_set(&net->ipv4.tfo_active_disable_times, 0);
 445
 446         return ret;
 447 }
 448
 449 static int proc_tcp_available_ulp(struct ctl_table *ctl,
 450                                   int write,
 451                                   void __user *buffer, size_t *lenp,
 452                                   loff_t *ppos)
 453 {
 454         struct ctl_table tbl = { .maxlen = TCP_ULP_BUF_MAX, };
 455         int ret;
 456
 457         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 458         if (!tbl.data)
 459                 return -ENOMEM;
 460         tcp_get_available_ulp(tbl.data, TCP_ULP_BUF_MAX);
 461         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 462         kfree(tbl.data);
 463
 464         return ret;
 465 }
 466
 467 #ifdef CONFIG_IP_ROUTE_MULTIPATH
 468 static int proc_fib_multipath_hash_policy(struct ctl_table *table, int write,
 469                                           void __user *buffer, size_t *lenp,
 470                                           loff_t *ppos)
 471 {
 472         struct net *net = container_of(table->data, struct net,
 473             ipv4.sysctl_fib_multipath_hash_policy);
 474         int ret;
 475
 476         ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 477         if (write && ret == 0)
 478                 call_netevent_notifiers(NETEVENT_IPV4_MPATH_HASH_UPDATE, net);
 479
 480         return ret;
 481 }
 482 #endif
 483
 484 static struct ctl_table ipv4_table[] = {
 485         {
 486                 .procname       = "tcp_max_orphans",
 487                 .data           = &sysctl_tcp_max_orphans,
 488                 .maxlen         = sizeof(int),
 489                 .mode           = 0644,
 490                 .proc_handler   = proc_dointvec
 491         },
 492         {
 493                 .procname       = "inet_peer_threshold",
 494                 .data           = &inet_peer_threshold,
 495                 .maxlen         = sizeof(int),
 496                 .mode           = 0644,
 497                 .proc_handler   = proc_dointvec
 498         },
 499         {
 500                 .procname       = "inet_peer_minttl",
 501                 .data           = &inet_peer_minttl,
 502                 .maxlen         = sizeof(int),
 503                 .mode           = 0644,
 504                 .proc_handler   = proc_dointvec_jiffies,
 505         },
 506         {
 507                 .procname       = "inet_peer_maxttl",
 508                 .data           = &inet_peer_maxttl,
 509                 .maxlen         = sizeof(int),
 510                 .mode           = 0644,
 511                 .proc_handler   = proc_dointvec_jiffies,
 512         },
 513         {
 514                 .procname       = "tcp_mem",
 515                 .maxlen         = sizeof(sysctl_tcp_mem),
 516                 .data           = &sysctl_tcp_mem,
 517                 .mode           = 0644,
 518                 .proc_handler   = proc_doulongvec_minmax,
 519         },
 520         {
 521                 .procname       = "tcp_low_latency",
 522                 .data           = &sysctl_tcp_low_latency,
 523                 .maxlen         = sizeof(int),
 524                 .mode           = 0644,
 525                 .proc_handler   = proc_dointvec
 526         },
 527 #ifdef CONFIG_NETLABEL
 528         {
 529                 .procname       = "cipso_cache_enable",
 530                 .data           = &cipso_v4_cache_enabled,
 531                 .maxlen         = sizeof(int),
 532                 .mode           = 0644,
 533                 .proc_handler   = proc_dointvec,
 534         },
 535         {
 536                 .procname       = "cipso_cache_bucket_size",
 537                 .data           = &cipso_v4_cache_bucketsize,
 538                 .maxlen         = sizeof(int),
 539                 .mode           = 0644,
 540                 .proc_handler   = proc_dointvec,
 541         },
 542         {
 543                 .procname       = "cipso_rbm_optfmt",
 544                 .data           = &cipso_v4_rbm_optfmt,
 545                 .maxlen         = sizeof(int),
 546                 .mode           = 0644,
 547                 .proc_handler   = proc_dointvec,
 548         },
 549         {
 550                 .procname       = "cipso_rbm_strictvalid",
 551                 .data           = &cipso_v4_rbm_strictvalid,
 552                 .maxlen         = sizeof(int),
 553                 .mode           = 0644,
 554                 .proc_handler   = proc_dointvec,
 555         },
 556 #endif /* CONFIG_NETLABEL */
 557         {
 558                 .procname       = "tcp_available_ulp",
 559                 .maxlen         = TCP_ULP_BUF_MAX,
 560                 .mode           = 0444,
 561                 .proc_handler   = proc_tcp_available_ulp,
 562         },
 563         {
 564                 .procname       = "icmp_msgs_per_sec",
 565                 .data           = &sysctl_icmp_msgs_per_sec,
 566                 .maxlen         = sizeof(int),
 567                 .mode           = 0644,
 568                 .proc_handler   = proc_dointvec_minmax,
 569                 .extra1         = SYSCTL_ZERO,
 570         },
 571         {
 572                 .procname       = "icmp_msgs_burst",
 573                 .data           = &sysctl_icmp_msgs_burst,
 574                 .maxlen         = sizeof(int),
 575                 .mode           = 0644,
 576                 .proc_handler   = proc_dointvec_minmax,
 577                 .extra1         = SYSCTL_ZERO,
 578         },
 579         {
 580                 .procname       = "udp_mem",
 581                 .data           = &sysctl_udp_mem,
 582                 .maxlen         = sizeof(sysctl_udp_mem),
 583                 .mode           = 0644,
 584                 .proc_handler   = proc_doulongvec_minmax,
 585         },
 586         {
 587                 .procname       = "fib_sync_mem",
 588                 .data           = &sysctl_fib_sync_mem,
 589                 .maxlen         = sizeof(sysctl_fib_sync_mem),
 590                 .mode           = 0644,
 591                 .proc_handler   = proc_douintvec_minmax,
 592                 .extra1         = &sysctl_fib_sync_mem_min,
 593                 .extra2         = &sysctl_fib_sync_mem_max,
 594         },
 595         {
 596                 .procname       = "tcp_rx_skb_cache",
 597                 .data           = &tcp_rx_skb_cache_key.key,
 598                 .mode           = 0644,
 599                 .proc_handler   = proc_do_static_key,
 600         },
 601         {
 602                 .procname       = "tcp_tx_skb_cache",
 603                 .data           = &tcp_tx_skb_cache_key.key,
 604                 .mode           = 0644,
 605                 .proc_handler   = proc_do_static_key,
 606         },
 607         { }
 608 };
 609
 610 static struct ctl_table ipv4_net_table[] = {
 611         {
 612                 .procname       = "icmp_echo_ignore_all",
 613                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
 614                 .maxlen         = sizeof(int),
 615                 .mode           = 0644,
 616                 .proc_handler   = proc_dointvec
 617         },
 618         {
 619                 .procname       = "icmp_echo_ignore_broadcasts",
 620                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
 621                 .maxlen         = sizeof(int),
 622                 .mode           = 0644,
 623                 .proc_handler   = proc_dointvec
 624         },
 625         {
 626                 .procname       = "icmp_ignore_bogus_error_responses",
 627                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
 628                 .maxlen         = sizeof(int),
 629                 .mode           = 0644,
 630                 .proc_handler   = proc_dointvec
 631         },
 632         {
 633                 .procname       = "icmp_errors_use_inbound_ifaddr",
 634                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
 635                 .maxlen         = sizeof(int),
 636                 .mode           = 0644,
 637                 .proc_handler   = proc_dointvec
 638         },
 639         {
 640                 .procname       = "icmp_ratelimit",
 641                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
 642                 .maxlen         = sizeof(int),
 643                 .mode           = 0644,
 644                 .proc_handler   = proc_dointvec_ms_jiffies,
 645         },
 646         {
 647                 .procname       = "icmp_ratemask",
 648                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
 649                 .maxlen         = sizeof(int),
 650                 .mode           = 0644,
 651                 .proc_handler   = proc_dointvec
 652         },
 653         {
 654                 .procname       = "ping_group_range",
 655                 .data           = &init_net.ipv4.ping_group_range.range,
 656                 .maxlen         = sizeof(gid_t)*2,
 657                 .mode           = 0644,
 658                 .proc_handler   = ipv4_ping_group_range,
 659         },
 660 #ifdef CONFIG_NET_L3_MASTER_DEV
 661         {
 662                 .procname       = "raw_l3mdev_accept",
 663                 .data           = &init_net.ipv4.sysctl_raw_l3mdev_accept,
 664                 .maxlen         = sizeof(int),
 665                 .mode           = 0644,
 666                 .proc_handler   = proc_dointvec_minmax,
 667                 .extra1         = SYSCTL_ZERO,
 668                 .extra2         = SYSCTL_ONE,
 669         },
 670 #endif
 671         {
 672                 .procname       = "tcp_ecn",
 673                 .data           = &init_net.ipv4.sysctl_tcp_ecn,
 674                 .maxlen         = sizeof(int),
 675                 .mode           = 0644,
 676                 .proc_handler   = proc_dointvec
 677         },
 678         {
 679                 .procname       = "tcp_ecn_fallback",
 680                 .data           = &init_net.ipv4.sysctl_tcp_ecn_fallback,
 681                 .maxlen         = sizeof(int),
 682                 .mode           = 0644,
 683                 .proc_handler   = proc_dointvec
 684         },
 685         {
 686                 .procname       = "ip_dynaddr",
 687                 .data           = &init_net.ipv4.sysctl_ip_dynaddr,
 688                 .maxlen         = sizeof(int),
 689                 .mode           = 0644,
 690                 .proc_handler   = proc_dointvec
 691         },
 692         {
 693                 .procname       = "ip_early_demux",
 694                 .data           = &init_net.ipv4.sysctl_ip_early_demux,
 695                 .maxlen         = sizeof(int),
 696                 .mode           = 0644,
 697                 .proc_handler   = proc_dointvec
 698         },
 699         {
 700                 .procname       = "udp_early_demux",
 701                 .data           = &init_net.ipv4.sysctl_udp_early_demux,
 702                 .maxlen         = sizeof(int),
 703                 .mode           = 0644,
 704                 .proc_handler   = proc_udp_early_demux
 705         },
 706         {
 707                 .procname       = "tcp_early_demux",
 708                 .data           = &init_net.ipv4.sysctl_tcp_early_demux,
 709                 .maxlen         = sizeof(int),
 710                 .mode           = 0644,
 711                 .proc_handler   = proc_tcp_early_demux
 712         },
 713         {
 714                 .procname       = "ip_default_ttl",
 715                 .data           = &init_net.ipv4.sysctl_ip_default_ttl,
 716                 .maxlen         = sizeof(int),
 717                 .mode           = 0644,
 718                 .proc_handler   = proc_dointvec_minmax,
 719                 .extra1         = &ip_ttl_min,
 720                 .extra2         = &ip_ttl_max,
 721         },
 722         {
 723                 .procname       = "ip_local_port_range",
 724                 .maxlen         = sizeof(init_net.ipv4.ip_local_ports.range),
 725                 .data           = &init_net.ipv4.ip_local_ports.range,
 726                 .mode           = 0644,
 727                 .proc_handler   = ipv4_local_port_range,
 728         },
 729         {
 730                 .procname       = "ip_local_reserved_ports",
 731                 .data           = &init_net.ipv4.sysctl_local_reserved_ports,
 732                 .maxlen         = 65536,
 733                 .mode           = 0644,
 734                 .proc_handler   = proc_do_large_bitmap,
 735         },
 736         {
 737                 .procname       = "ip_no_pmtu_disc",
 738                 .data           = &init_net.ipv4.sysctl_ip_no_pmtu_disc,
 739                 .maxlen         = sizeof(int),
 740                 .mode           = 0644,
 741                 .proc_handler   = proc_dointvec
 742         },
 743         {
 744                 .procname       = "ip_forward_use_pmtu",
 745                 .data           = &init_net.ipv4.sysctl_ip_fwd_use_pmtu,
 746                 .maxlen         = sizeof(int),
 747                 .mode           = 0644,
 748                 .proc_handler   = proc_dointvec,
 749         },
 750         {
 751                 .procname       = "ip_forward_update_priority",
 752                 .data           = &init_net.ipv4.sysctl_ip_fwd_update_priority,
 753                 .maxlen         = sizeof(int),
 754                 .mode           = 0644,
 755                 .proc_handler   = ipv4_fwd_update_priority,
 756                 .extra1         = SYSCTL_ZERO,
 757                 .extra2         = SYSCTL_ONE,
 758         },
 759         {
 760                 .procname       = "ip_nonlocal_bind",
 761                 .data           = &init_net.ipv4.sysctl_ip_nonlocal_bind,
 762                 .maxlen         = sizeof(int),
 763                 .mode           = 0644,
 764                 .proc_handler   = proc_dointvec
 765         },
 766         {
 767                 .procname       = "ip_autobind_reuse",
 768                 .data           = &init_net.ipv4.sysctl_ip_autobind_reuse,
 769                 .maxlen         = sizeof(int),
 770                 .mode           = 0644,
 771                 .proc_handler   = proc_dointvec_minmax,
 772                 .extra1         = SYSCTL_ZERO,
 773                 .extra2         = SYSCTL_ONE,
 774         },
 775         {
 776                 .procname       = "fwmark_reflect",
 777                 .data           = &init_net.ipv4.sysctl_fwmark_reflect,
 778                 .maxlen         = sizeof(int),
 779                 .mode           = 0644,
 780                 .proc_handler   = proc_dointvec,
 781         },
 782         {
 783                 .procname       = "tcp_fwmark_accept",
 784                 .data           = &init_net.ipv4.sysctl_tcp_fwmark_accept,
 785                 .maxlen         = sizeof(int),
 786                 .mode           = 0644,
 787                 .proc_handler   = proc_dointvec,
 788         },
 789 #ifdef CONFIG_NET_L3_MASTER_DEV
 790         {
 791                 .procname       = "tcp_l3mdev_accept",
 792                 .data           = &init_net.ipv4.sysctl_tcp_l3mdev_accept,
 793                 .maxlen         = sizeof(int),
 794                 .mode           = 0644,
 795                 .proc_handler   = proc_dointvec_minmax,
 796                 .extra1         = SYSCTL_ZERO,
 797                 .extra2         = SYSCTL_ONE,
 798         },
 799 #endif
 800         {
 801                 .procname       = "tcp_mtu_probing",
 802                 .data           = &init_net.ipv4.sysctl_tcp_mtu_probing,
 803                 .maxlen         = sizeof(int),
 804                 .mode           = 0644,
 805                 .proc_handler   = proc_dointvec,
 806         },
 807         {
 808                 .procname       = "tcp_base_mss",
 809                 .data           = &init_net.ipv4.sysctl_tcp_base_mss,
 810                 .maxlen         = sizeof(int),
 811                 .mode           = 0644,
 812                 .proc_handler   = proc_dointvec,
 813         },
 814         {
 815                 .procname       = "tcp_min_snd_mss",
 816                 .data           = &init_net.ipv4.sysctl_tcp_min_snd_mss,
 817                 .maxlen         = sizeof(int),
 818                 .mode           = 0644,
 819                 .proc_handler   = proc_dointvec_minmax,
 820                 .extra1         = &tcp_min_snd_mss_min,
 821                 .extra2         = &tcp_min_snd_mss_max,
 822         },
 823         {
 824                 .procname       = "tcp_mtu_probe_floor",
 825                 .data           = &init_net.ipv4.sysctl_tcp_mtu_probe_floor,
 826                 .maxlen         = sizeof(int),
 827                 .mode           = 0644,
 828                 .proc_handler   = proc_dointvec_minmax,
 829                 .extra1         = &tcp_min_snd_mss_min,
 830                 .extra2         = &tcp_min_snd_mss_max,
 831         },
 832         {
 833                 .procname       = "tcp_probe_threshold",
 834                 .data           = &init_net.ipv4.sysctl_tcp_probe_threshold,
 835                 .maxlen         = sizeof(int),
 836                 .mode           = 0644,
 837                 .proc_handler   = proc_dointvec,
 838         },
 839         {
 840                 .procname       = "tcp_probe_interval",
 841                 .data           = &init_net.ipv4.sysctl_tcp_probe_interval,
 842                 .maxlen         = sizeof(u32),
 843                 .mode           = 0644,
 844                 .proc_handler   = proc_douintvec_minmax,
 845                 .extra2         = &u32_max_div_HZ,
 846         },
 847         {
 848                 .procname       = "igmp_link_local_mcast_reports",
 849                 .data           = &init_net.ipv4.sysctl_igmp_llm_reports,
 850                 .maxlen         = sizeof(int),
 851                 .mode           = 0644,
 852                 .proc_handler   = proc_dointvec
 853         },
 854         {
 855                 .procname       = "igmp_max_memberships",
 856                 .data           = &init_net.ipv4.sysctl_igmp_max_memberships,
 857                 .maxlen         = sizeof(int),
 858                 .mode           = 0644,
 859                 .proc_handler   = proc_dointvec
 860         },
 861         {
 862                 .procname       = "igmp_max_msf",
 863                 .data           = &init_net.ipv4.sysctl_igmp_max_msf,
 864                 .maxlen         = sizeof(int),
 865                 .mode           = 0644,
 866                 .proc_handler   = proc_dointvec
 867         },
 868 #ifdef CONFIG_IP_MULTICAST
 869         {
 870                 .procname       = "igmp_qrv",
 871                 .data           = &init_net.ipv4.sysctl_igmp_qrv,
 872                 .maxlen         = sizeof(int),
 873                 .mode           = 0644,
 874                 .proc_handler   = proc_dointvec_minmax,
 875                 .extra1         = SYSCTL_ONE
 876         },
 877 #endif
 878         {
 879                 .procname       = "tcp_congestion_control",
 880                 .data           = &init_net.ipv4.tcp_congestion_control,
 881                 .mode           = 0644,
 882                 .maxlen         = TCP_CA_NAME_MAX,
 883                 .proc_handler   = proc_tcp_congestion_control,
 884         },
 885         {
 886                 .procname       = "tcp_available_congestion_control",
 887                 .maxlen         = TCP_CA_BUF_MAX,
 888                 .mode           = 0444,
 889                 .proc_handler   = proc_tcp_available_congestion_control,
 890         },
 891         {
 892                 .procname       = "tcp_allowed_congestion_control",
 893                 .maxlen         = TCP_CA_BUF_MAX,
 894                 .mode           = 0644,
 895                 .proc_handler   = proc_allowed_congestion_control,
 896         },
 897         {
 898                 .procname       = "tcp_keepalive_time",
 899                 .data           = &init_net.ipv4.sysctl_tcp_keepalive_time,
 900                 .maxlen         = sizeof(int),
 901                 .mode           = 0644,
 902                 .proc_handler   = proc_dointvec_jiffies,
 903         },
 904         {
 905                 .procname       = "tcp_keepalive_probes",
 906                 .data           = &init_net.ipv4.sysctl_tcp_keepalive_probes,
 907                 .maxlen         = sizeof(int),
 908                 .mode           = 0644,
 909                 .proc_handler   = proc_dointvec
 910         },
 911         {
 912                 .procname       = "tcp_keepalive_intvl",
 913                 .data           = &init_net.ipv4.sysctl_tcp_keepalive_intvl,
 914                 .maxlen         = sizeof(int),
 915                 .mode           = 0644,
 916                 .proc_handler   = proc_dointvec_jiffies,
 917         },
 918         {
 919                 .procname       = "tcp_syn_retries",
 920                 .data           = &init_net.ipv4.sysctl_tcp_syn_retries,
 921                 .maxlen         = sizeof(int),
 922                 .mode           = 0644,
 923                 .proc_handler   = proc_dointvec_minmax,
 924                 .extra1         = &tcp_syn_retries_min,
 925                 .extra2         = &tcp_syn_retries_max
 926         },
 927         {
 928                 .procname       = "tcp_synack_retries",
 929                 .data           = &init_net.ipv4.sysctl_tcp_synack_retries,
 930                 .maxlen         = sizeof(int),
 931                 .mode           = 0644,
 932                 .proc_handler   = proc_dointvec
 933         },
 934 #ifdef CONFIG_SYN_COOKIES
 935         {
 936                 .procname       = "tcp_syncookies",
 937                 .data           = &init_net.ipv4.sysctl_tcp_syncookies,
 938                 .maxlen         = sizeof(int),
 939                 .mode           = 0644,
 940                 .proc_handler   = proc_dointvec
 941         },
 942 #endif
 943         {
 944                 .procname       = "tcp_reordering",
 945                 .data           = &init_net.ipv4.sysctl_tcp_reordering,
 946                 .maxlen         = sizeof(int),
 947                 .mode           = 0644,
 948                 .proc_handler   = proc_dointvec
 949         },
 950         {
 951                 .procname       = "tcp_retries1",
 952                 .data           = &init_net.ipv4.sysctl_tcp_retries1,
 953                 .maxlen         = sizeof(int),
 954                 .mode           = 0644,
 955                 .proc_handler   = proc_dointvec_minmax,
 956                 .extra2         = &tcp_retr1_max
 957         },
 958         {
 959                 .procname       = "tcp_retries2",
 960                 .data           = &init_net.ipv4.sysctl_tcp_retries2,
 961                 .maxlen         = sizeof(int),
 962                 .mode           = 0644,
 963                 .proc_handler   = proc_dointvec
 964         },
 965         {
 966                 .procname       = "tcp_orphan_retries",
 967                 .data           = &init_net.ipv4.sysctl_tcp_orphan_retries,
 968                 .maxlen         = sizeof(int),
 969                 .mode           = 0644,
 970                 .proc_handler   = proc_dointvec
 971         },
 972         {
 973                 .procname       = "tcp_fin_timeout",
 974                 .data           = &init_net.ipv4.sysctl_tcp_fin_timeout,
 975                 .maxlen         = sizeof(int),
 976                 .mode           = 0644,
 977                 .proc_handler   = proc_dointvec_jiffies,
 978         },
 979         {
 980                 .procname       = "tcp_notsent_lowat",
 981                 .data           = &init_net.ipv4.sysctl_tcp_notsent_lowat,
 982                 .maxlen         = sizeof(unsigned int),
 983                 .mode           = 0644,
 984                 .proc_handler   = proc_douintvec,
 985         },
 986         {
 987                 .procname       = "tcp_tw_reuse",
 988                 .data           = &init_net.ipv4.sysctl_tcp_tw_reuse,
 989                 .maxlen         = sizeof(int),
 990                 .mode           = 0644,
 991                 .proc_handler   = proc_dointvec_minmax,
 992                 .extra1         = SYSCTL_ZERO,
 993                 .extra2         = &two,
 994         },
 995         {
 996                 .procname       = "tcp_max_tw_buckets",
 997                 .data           = &init_net.ipv4.tcp_death_row.sysctl_max_tw_buckets,
 998                 .maxlen         = sizeof(int),
 999                 .mode           = 0644,
1000                 .proc_handler   = proc_dointvec
1001         },
1002         {
1003                 .procname       = "tcp_max_syn_backlog",
1004                 .data           = &init_net.ipv4.sysctl_max_syn_backlog,
1005                 .maxlen         = sizeof(int),
1006                 .mode           = 0644,
1007                 .proc_handler   = proc_dointvec
1008         },
1009         {
1010                 .procname       = "tcp_fastopen",
1011                 .data           = &init_net.ipv4.sysctl_tcp_fastopen,
1012                 .maxlen         = sizeof(int),
1013                 .mode           = 0644,
1014                 .proc_handler   = proc_dointvec,
1015         },
1016         {
1017                 .procname       = "tcp_fastopen_key",
1018                 .mode           = 0600,
1019                 .data           = &init_net.ipv4.sysctl_tcp_fastopen,
1020                 /* maxlen to print the list of keys in hex (*2), with dashes
1021                  * separating doublewords and a comma in between keys.
1022                  */
1023                 .maxlen         = ((TCP_FASTOPEN_KEY_LENGTH *
1024                                    2 * TCP_FASTOPEN_KEY_MAX) +
1025                                    (TCP_FASTOPEN_KEY_MAX * 5)),
1026                 .proc_handler   = proc_tcp_fastopen_key,
1027         },
1028         {
1029                 .procname       = "tcp_fastopen_blackhole_timeout_sec",
1030                 .data           = &init_net.ipv4.sysctl_tcp_fastopen_blackhole_timeout,
1031                 .maxlen         = sizeof(int),
1032                 .mode           = 0644,
1033                 .proc_handler   = proc_tfo_blackhole_detect_timeout,
1034                 .extra1         = SYSCTL_ZERO,
1035         },
1036 #ifdef CONFIG_IP_ROUTE_MULTIPATH
1037         {
1038                 .procname       = "fib_multipath_use_neigh",
1039                 .data           = &init_net.ipv4.sysctl_fib_multipath_use_neigh,
1040                 .maxlen         = sizeof(int),
1041                 .mode           = 0644,
1042                 .proc_handler   = proc_dointvec_minmax,
1043                 .extra1         = SYSCTL_ZERO,
1044                 .extra2         = SYSCTL_ONE,
1045         },
1046         {
1047                 .procname       = "fib_multipath_hash_policy",
1048                 .data           = &init_net.ipv4.sysctl_fib_multipath_hash_policy,
1049                 .maxlen         = sizeof(int),
1050                 .mode           = 0644,
1051                 .proc_handler   = proc_fib_multipath_hash_policy,
1052                 .extra1         = SYSCTL_ZERO,
1053                 .extra2         = &two,
1054         },
1055 #endif
1056         {
1057                 .procname       = "ip_unprivileged_port_start",
1058                 .maxlen         = sizeof(int),
1059                 .data           = &init_net.ipv4.sysctl_ip_prot_sock,
1060                 .mode           = 0644,
1061                 .proc_handler   = ipv4_privileged_ports,
1062         },
1063 #ifdef CONFIG_NET_L3_MASTER_DEV
1064         {
1065                 .procname       = "udp_l3mdev_accept",
1066                 .data           = &init_net.ipv4.sysctl_udp_l3mdev_accept,
1067                 .maxlen         = sizeof(int),
1068                 .mode           = 0644,
1069                 .proc_handler   = proc_dointvec_minmax,
1070                 .extra1         = SYSCTL_ZERO,
1071                 .extra2         = SYSCTL_ONE,
1072         },
1073 #endif
1074         {
1075                 .procname       = "tcp_sack",
1076                 .data           = &init_net.ipv4.sysctl_tcp_sack,
1077                 .maxlen         = sizeof(int),
1078                 .mode           = 0644,
1079                 .proc_handler   = proc_dointvec
1080         },
1081         {
1082                 .procname       = "tcp_window_scaling",
1083                 .data           = &init_net.ipv4.sysctl_tcp_window_scaling,
1084                 .maxlen         = sizeof(int),
1085                 .mode           = 0644,
1086                 .proc_handler   = proc_dointvec
1087         },
1088         {
1089                 .procname       = "tcp_timestamps",
1090                 .data           = &init_net.ipv4.sysctl_tcp_timestamps,
1091                 .maxlen         = sizeof(int),
1092                 .mode           = 0644,
1093                 .proc_handler   = proc_dointvec
1094         },
1095         {
1096                 .procname       = "tcp_early_retrans",
1097                 .data           = &init_net.ipv4.sysctl_tcp_early_retrans,
1098                 .maxlen         = sizeof(int),
1099                 .mode           = 0644,
1100                 .proc_handler   = proc_dointvec_minmax,
1101                 .extra1         = SYSCTL_ZERO,
1102                 .extra2         = &four,
1103         },
1104         {
1105                 .procname       = "tcp_recovery",
1106                 .data           = &init_net.ipv4.sysctl_tcp_recovery,
1107                 .maxlen         = sizeof(int),
1108                 .mode           = 0644,
1109                 .proc_handler   = proc_dointvec,
1110         },
1111         {
1112                 .procname       = "tcp_thin_linear_timeouts",
1113                 .data           = &init_net.ipv4.sysctl_tcp_thin_linear_timeouts,
1114                 .maxlen         = sizeof(int),
1115                 .mode           = 0644,
1116                 .proc_handler   = proc_dointvec
1117         },
1118         {
1119                 .procname       = "tcp_slow_start_after_idle",
1120                 .data           = &init_net.ipv4.sysctl_tcp_slow_start_after_idle,
1121                 .maxlen         = sizeof(int),
1122                 .mode           = 0644,
1123                 .proc_handler   = proc_dointvec
1124         },
1125         {
1126                 .procname       = "tcp_retrans_collapse",
1127                 .data           = &init_net.ipv4.sysctl_tcp_retrans_collapse,
1128                 .maxlen         = sizeof(int),
1129                 .mode           = 0644,
1130                 .proc_handler   = proc_dointvec
1131         },
1132         {
1133                 .procname       = "tcp_stdurg",
1134                 .data           = &init_net.ipv4.sysctl_tcp_stdurg,
1135                 .maxlen         = sizeof(int),
1136                 .mode           = 0644,
1137                 .proc_handler   = proc_dointvec
1138         },
1139         {
1140                 .procname       = "tcp_rfc1337",
1141                 .data           = &init_net.ipv4.sysctl_tcp_rfc1337,
1142                 .maxlen         = sizeof(int),
1143                 .mode           = 0644,
1144                 .proc_handler   = proc_dointvec
1145         },
1146         {
1147                 .procname       = "tcp_abort_on_overflow",
1148                 .data           = &init_net.ipv4.sysctl_tcp_abort_on_overflow,
1149                 .maxlen         = sizeof(int),
1150                 .mode           = 0644,
1151                 .proc_handler   = proc_dointvec
1152         },
1153         {
1154                 .procname       = "tcp_fack",
1155                 .data           = &init_net.ipv4.sysctl_tcp_fack,
1156                 .maxlen         = sizeof(int),
1157                 .mode           = 0644,
1158                 .proc_handler   = proc_dointvec
1159         },
1160         {
1161                 .procname       = "tcp_max_reordering",
1162                 .data           = &init_net.ipv4.sysctl_tcp_max_reordering,
1163                 .maxlen         = sizeof(int),
1164                 .mode           = 0644,
1165                 .proc_handler   = proc_dointvec
1166         },
1167         {
1168                 .procname       = "tcp_dsack",
1169                 .data           = &init_net.ipv4.sysctl_tcp_dsack,
1170                 .maxlen         = sizeof(int),
1171                 .mode           = 0644,
1172                 .proc_handler   = proc_dointvec
1173         },
1174         {
1175                 .procname       = "tcp_app_win",
1176                 .data           = &init_net.ipv4.sysctl_tcp_app_win,
1177                 .maxlen         = sizeof(int),
1178                 .mode           = 0644,
1179                 .proc_handler   = proc_dointvec
1180         },
1181         {
1182                 .procname       = "tcp_adv_win_scale",
1183                 .data           = &init_net.ipv4.sysctl_tcp_adv_win_scale,
1184                 .maxlen         = sizeof(int),
1185                 .mode           = 0644,
1186                 .proc_handler   = proc_dointvec_minmax,
1187                 .extra1         = &tcp_adv_win_scale_min,
1188                 .extra2         = &tcp_adv_win_scale_max,
1189         },
1190         {
1191                 .procname       = "tcp_frto",
1192                 .data           = &init_net.ipv4.sysctl_tcp_frto,
1193                 .maxlen         = sizeof(int),
1194                 .mode           = 0644,
1195                 .proc_handler   = proc_dointvec
1196         },
1197         {
1198                 .procname       = "tcp_no_metrics_save",
1199                 .data           = &init_net.ipv4.sysctl_tcp_nometrics_save,
1200                 .maxlen         = sizeof(int),
1201                 .mode           = 0644,
1202                 .proc_handler   = proc_dointvec,
1203         },
1204         {
1205                 .procname       = "tcp_no_ssthresh_metrics_save",
1206                 .data           = &init_net.ipv4.sysctl_tcp_no_ssthresh_metrics_save,
1207                 .maxlen         = sizeof(int),
1208                 .mode           = 0644,
1209                 .proc_handler   = proc_dointvec_minmax,
1210                 .extra1         = SYSCTL_ZERO,
1211                 .extra2         = SYSCTL_ONE,
1212         },
1213         {
1214                 .procname       = "tcp_moderate_rcvbuf",
1215                 .data           = &init_net.ipv4.sysctl_tcp_moderate_rcvbuf,
1216                 .maxlen         = sizeof(int),
1217                 .mode           = 0644,
1218                 .proc_handler   = proc_dointvec,
1219         },
1220         {
1221                 .procname       = "tcp_tso_win_divisor",
1222                 .data           = &init_net.ipv4.sysctl_tcp_tso_win_divisor,
1223                 .maxlen         = sizeof(int),
1224                 .mode           = 0644,
1225                 .proc_handler   = proc_dointvec,
1226         },
1227         {
1228                 .procname       = "tcp_workaround_signed_windows",
1229                 .data           = &init_net.ipv4.sysctl_tcp_workaround_signed_windows,
1230                 .maxlen         = sizeof(int),
1231                 .mode           = 0644,
1232                 .proc_handler   = proc_dointvec
1233         },
1234         {
1235                 .procname       = "tcp_limit_output_bytes",
1236                 .data           = &init_net.ipv4.sysctl_tcp_limit_output_bytes,
1237                 .maxlen         = sizeof(int),
1238                 .mode           = 0644,
1239                 .proc_handler   = proc_dointvec
1240         },
1241         {
1242                 .procname       = "tcp_challenge_ack_limit",
1243                 .data           = &init_net.ipv4.sysctl_tcp_challenge_ack_limit,
1244                 .maxlen         = sizeof(int),
1245                 .mode           = 0644,
1246                 .proc_handler   = proc_dointvec
1247         },
1248         {
1249                 .procname       = "tcp_min_tso_segs",
1250                 .data           = &init_net.ipv4.sysctl_tcp_min_tso_segs,
1251                 .maxlen         = sizeof(int),
1252                 .mode           = 0644,
1253                 .proc_handler   = proc_dointvec_minmax,
1254                 .extra1         = SYSCTL_ONE,
1255                 .extra2         = &gso_max_segs,
1256         },
1257         {
1258                 .procname       = "tcp_min_rtt_wlen",
1259                 .data           = &init_net.ipv4.sysctl_tcp_min_rtt_wlen,
1260                 .maxlen         = sizeof(int),
1261                 .mode           = 0644,
1262                 .proc_handler   = proc_dointvec_minmax,
1263                 .extra1         = SYSCTL_ZERO,
1264                 .extra2         = &one_day_secs
1265         },
1266         {
1267                 .procname       = "tcp_autocorking",
1268                 .data           = &init_net.ipv4.sysctl_tcp_autocorking,
1269                 .maxlen         = sizeof(int),
1270                 .mode           = 0644,
1271                 .proc_handler   = proc_dointvec_minmax,
1272                 .extra1         = SYSCTL_ZERO,
1273                 .extra2         = SYSCTL_ONE,
1274         },
1275         {
1276                 .procname       = "tcp_invalid_ratelimit",
1277                 .data           = &init_net.ipv4.sysctl_tcp_invalid_ratelimit,
1278                 .maxlen         = sizeof(int),
1279                 .mode           = 0644,
1280                 .proc_handler   = proc_dointvec_ms_jiffies,
1281         },
1282         {
1283                 .procname       = "tcp_pacing_ss_ratio",
1284                 .data           = &init_net.ipv4.sysctl_tcp_pacing_ss_ratio,
1285                 .maxlen         = sizeof(int),
1286                 .mode           = 0644,
1287                 .proc_handler   = proc_dointvec_minmax,
1288                 .extra1         = SYSCTL_ZERO,
1289                 .extra2         = &thousand,
1290         },
1291         {
1292                 .procname       = "tcp_pacing_ca_ratio",
1293                 .data           = &init_net.ipv4.sysctl_tcp_pacing_ca_ratio,
1294                 .maxlen         = sizeof(int),
1295                 .mode           = 0644,
1296                 .proc_handler   = proc_dointvec_minmax,
1297                 .extra1         = SYSCTL_ZERO,
1298                 .extra2         = &thousand,
1299         },
1300         {
1301                 .procname       = "tcp_wmem",
1302                 .data           = &init_net.ipv4.sysctl_tcp_wmem,
1303                 .maxlen         = sizeof(init_net.ipv4.sysctl_tcp_wmem),
1304                 .mode           = 0644,
1305                 .proc_handler   = proc_dointvec_minmax,
1306                 .extra1         = SYSCTL_ONE,
1307         },
1308         {
1309                 .procname       = "tcp_rmem",
1310                 .data           = &init_net.ipv4.sysctl_tcp_rmem,
1311                 .maxlen         = sizeof(init_net.ipv4.sysctl_tcp_rmem),
1312                 .mode           = 0644,
1313                 .proc_handler   = proc_dointvec_minmax,
1314                 .extra1         = SYSCTL_ONE,
1315         },
1316         {
1317                 .procname       = "tcp_comp_sack_delay_ns",
1318                 .data           = &init_net.ipv4.sysctl_tcp_comp_sack_delay_ns,
1319                 .maxlen         = sizeof(unsigned long),
1320                 .mode           = 0644,
1321                 .proc_handler   = proc_doulongvec_minmax,
1322         },
1323         {
1324                 .procname       = "tcp_comp_sack_nr",
1325                 .data           = &init_net.ipv4.sysctl_tcp_comp_sack_nr,
1326                 .maxlen         = sizeof(int),
1327                 .mode           = 0644,
1328                 .proc_handler   = proc_dointvec_minmax,
1329                 .extra1         = SYSCTL_ZERO,
1330                 .extra2         = &comp_sack_nr_max,
1331         },
1332         {
1333                 .procname       = "udp_rmem_min",
1334                 .data           = &init_net.ipv4.sysctl_udp_rmem_min,
1335                 .maxlen         = sizeof(init_net.ipv4.sysctl_udp_rmem_min),
1336                 .mode           = 0644,
1337                 .proc_handler   = proc_dointvec_minmax,
1338                 .extra1         = SYSCTL_ONE
1339         },
1340         {
1341                 .procname       = "udp_wmem_min",
1342                 .data           = &init_net.ipv4.sysctl_udp_wmem_min,
1343                 .maxlen         = sizeof(init_net.ipv4.sysctl_udp_wmem_min),
1344                 .mode           = 0644,
1345                 .proc_handler   = proc_dointvec_minmax,
1346                 .extra1         = SYSCTL_ONE
1347         },
1348         { }
1349 };
1350
1351 static __net_init int ipv4_sysctl_init_net(struct net *net)
1352 {
1353         struct ctl_table *table;
1354
1355         table = ipv4_net_table;
1356         if (!net_eq(net, &init_net)) {
1357                 int i;
1358
1359                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
1360                 if (!table)
1361                         goto err_alloc;
1362
1363                 /* Update the variables to point into the current struct net */
1364                 for (i = 0; i < ARRAY_SIZE(ipv4_net_table) - 1; i++)
1365                         table[i].data += (void *)net - (void *)&init_net;
1366         }
1367
1368         net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
1369         if (!net->ipv4.ipv4_hdr)
1370                 goto err_reg;
1371
1372         net->ipv4.sysctl_local_reserved_ports = kzalloc(65536 / 8, GFP_KERNEL);
1373         if (!net->ipv4.sysctl_local_reserved_ports)
1374                 goto err_ports;
1375
1376         return 0;
1377
1378 err_ports:
1379         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1380 err_reg:
1381         if (!net_eq(net, &init_net))
1382                 kfree(table);
1383 err_alloc:
1384         return -ENOMEM;
1385 }
1386
1387 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
1388 {
1389         struct ctl_table *table;
1390
1391         kfree(net->ipv4.sysctl_local_reserved_ports);
1392         table = net->ipv4.ipv4_hdr->ctl_table_arg;
1393         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
1394         kfree(table);
1395 }
1396
1397 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
1398         .init = ipv4_sysctl_init_net,
1399         .exit = ipv4_sysctl_exit_net,
1400 };
1401
1402 static __init int sysctl_ipv4_init(void)
1403 {
1404         struct ctl_table_header *hdr;
1405
1406         hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
1407         if (!hdr)
1408                 return -ENOMEM;
1409
1410         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
1411                 unregister_net_sysctl_table(hdr);
1412                 return -ENOMEM;
1413         }
1414
1415         return 0;
1416 }
1417
1418 __initcall(sysctl_ipv4_init);