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