net/ipv4/sysctl_net_ipv4.c

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