net/ipv4/sysctl_net_ipv4.c

   1 /*
   2  * sysctl_net_ipv4.c: sysctl interface to net IPV4 subsystem.
   3  *
   4  * Begun April 1, 1996, Mike Shaver.
   5  * Added /proc/sys/net/ipv4 directory entry (empty =) ). [MS]
   6  */
   7
   8 #include <linux/mm.h>
   9 #include <linux/module.h>
  10 #include <linux/sysctl.h>
  11 #include <linux/igmp.h>
  12 #include <linux/inetdevice.h>
  13 #include <linux/seqlock.h>
  14 #include <linux/init.h>
  15 #include <linux/slab.h>
  16 #include <linux/nsproxy.h>
  17 #include <linux/swap.h>
  18 #include <net/snmp.h>
  19 #include <net/icmp.h>
  20 #include <net/ip.h>
  21 #include <net/route.h>
  22 #include <net/tcp.h>
  23 #include <net/udp.h>
  24 #include <net/cipso_ipv4.h>
  25 #include <net/inet_frag.h>
  26 #include <net/ping.h>
  27 #include <net/tcp_memcontrol.h>
  28
  29 static int zero;
  30 static int one = 1;
  31 static int two = 2;
  32 static int tcp_retr1_max = 255;
  33 static int ip_local_port_range_min[] = { 1, 1 };
  34 static int ip_local_port_range_max[] = { 65535, 65535 };
  35 static int tcp_adv_win_scale_min = -31;
  36 static int tcp_adv_win_scale_max = 31;
  37 static int ip_ttl_min = 1;
  38 static int ip_ttl_max = 255;
  39 static int ip_ping_group_range_min[] = { 0, 0 };
  40 static int ip_ping_group_range_max[] = { GID_T_MAX, GID_T_MAX };
  41
  42 /* Update system visible IP port range */
  43 static void set_local_port_range(int range[2])
  44 {
  45         write_seqlock(&sysctl_local_ports.lock);
  46         sysctl_local_ports.range[0] = range[0];
  47         sysctl_local_ports.range[1] = range[1];
  48         write_sequnlock(&sysctl_local_ports.lock);
  49 }
  50
  51 /* Validate changes from /proc interface. */
  52 static int ipv4_local_port_range(ctl_table *table, int write,
  53                                  void __user *buffer,
  54                                  size_t *lenp, loff_t *ppos)
  55 {
  56         int ret;
  57         int range[2];
  58         ctl_table tmp = {
  59                 .data = &range,
  60                 .maxlen = sizeof(range),
  61                 .mode = table->mode,
  62                 .extra1 = &ip_local_port_range_min,
  63                 .extra2 = &ip_local_port_range_max,
  64         };
  65
  66         inet_get_local_port_range(range, range + 1);
  67         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
  68
  69         if (write && ret == 0) {
  70                 if (range[1] < range[0])
  71                         ret = -EINVAL;
  72                 else
  73                         set_local_port_range(range);
  74         }
  75
  76         return ret;
  77 }
  78
  79
  80 static void inet_get_ping_group_range_table(struct ctl_table *table, kgid_t *low, kgid_t *high)
  81 {
  82         kgid_t *data = table->data;
  83         unsigned int seq;
  84         do {
  85                 seq = read_seqbegin(&sysctl_local_ports.lock);
  86
  87                 *low = data[0];
  88                 *high = data[1];
  89         } while (read_seqretry(&sysctl_local_ports.lock, seq));
  90 }
  91
  92 /* Update system visible IP port range */
  93 static void set_ping_group_range(struct ctl_table *table, kgid_t low, kgid_t high)
  94 {
  95         kgid_t *data = table->data;
  96         write_seqlock(&sysctl_local_ports.lock);
  97         data[0] = low;
  98         data[1] = high;
  99         write_sequnlock(&sysctl_local_ports.lock);
 100 }
 101
 102 /* Validate changes from /proc interface. */
 103 static int ipv4_ping_group_range(ctl_table *table, int write,
 104                                  void __user *buffer,
 105                                  size_t *lenp, loff_t *ppos)
 106 {
 107         struct user_namespace *user_ns = current_user_ns();
 108         int ret;
 109         gid_t urange[2];
 110         kgid_t low, high;
 111         ctl_table tmp = {
 112                 .data = &urange,
 113                 .maxlen = sizeof(urange),
 114                 .mode = table->mode,
 115                 .extra1 = &ip_ping_group_range_min,
 116                 .extra2 = &ip_ping_group_range_max,
 117         };
 118
 119         inet_get_ping_group_range_table(table, &low, &high);
 120         urange[0] = from_kgid_munged(user_ns, low);
 121         urange[1] = from_kgid_munged(user_ns, high);
 122         ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 123
 124         if (write && ret == 0) {
 125                 low = make_kgid(user_ns, urange[0]);
 126                 high = make_kgid(user_ns, urange[1]);
 127                 if (!gid_valid(low) || !gid_valid(high) ||
 128                     (urange[1] < urange[0]) || gid_lt(high, low)) {
 129                         low = make_kgid(&init_user_ns, 1);
 130                         high = make_kgid(&init_user_ns, 0);
 131                 }
 132                 set_ping_group_range(table, low, high);
 133         }
 134
 135         return ret;
 136 }
 137
 138 static int proc_tcp_congestion_control(ctl_table *ctl, int write,
 139                                        void __user *buffer, size_t *lenp, loff_t *ppos)
 140 {
 141         char val[TCP_CA_NAME_MAX];
 142         ctl_table tbl = {
 143                 .data = val,
 144                 .maxlen = TCP_CA_NAME_MAX,
 145         };
 146         int ret;
 147
 148         tcp_get_default_congestion_control(val);
 149
 150         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 151         if (write && ret == 0)
 152                 ret = tcp_set_default_congestion_control(val);
 153         return ret;
 154 }
 155
 156 static int proc_tcp_available_congestion_control(ctl_table *ctl,
 157                                                  int write,
 158                                                  void __user *buffer, size_t *lenp,
 159                                                  loff_t *ppos)
 160 {
 161         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, };
 162         int ret;
 163
 164         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 165         if (!tbl.data)
 166                 return -ENOMEM;
 167         tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX);
 168         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 169         kfree(tbl.data);
 170         return ret;
 171 }
 172
 173 static int proc_allowed_congestion_control(ctl_table *ctl,
 174                                            int write,
 175                                            void __user *buffer, size_t *lenp,
 176                                            loff_t *ppos)
 177 {
 178         ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX };
 179         int ret;
 180
 181         tbl.data = kmalloc(tbl.maxlen, GFP_USER);
 182         if (!tbl.data)
 183                 return -ENOMEM;
 184
 185         tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen);
 186         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 187         if (write && ret == 0)
 188                 ret = tcp_set_allowed_congestion_control(tbl.data);
 189         kfree(tbl.data);
 190         return ret;
 191 }
 192
 193 static int ipv4_tcp_mem(ctl_table *ctl, int write,
 194                            void __user *buffer, size_t *lenp,
 195                            loff_t *ppos)
 196 {
 197         int ret;
 198         unsigned long vec[3];
 199         struct net *net = current->nsproxy->net_ns;
 200 #ifdef CONFIG_MEMCG_KMEM
 201         struct mem_cgroup *memcg;
 202 #endif
 203
 204         ctl_table tmp = {
 205                 .data = &vec,
 206                 .maxlen = sizeof(vec),
 207                 .mode = ctl->mode,
 208         };
 209
 210         if (!write) {
 211                 ctl->data = &net->ipv4.sysctl_tcp_mem;
 212                 return proc_doulongvec_minmax(ctl, write, buffer, lenp, ppos);
 213         }
 214
 215         ret = proc_doulongvec_minmax(&tmp, write, buffer, lenp, ppos);
 216         if (ret)
 217                 return ret;
 218
 219 #ifdef CONFIG_MEMCG_KMEM
 220         rcu_read_lock();
 221         memcg = mem_cgroup_from_task(current);
 222
 223         tcp_prot_mem(memcg, vec[0], 0);
 224         tcp_prot_mem(memcg, vec[1], 1);
 225         tcp_prot_mem(memcg, vec[2], 2);
 226         rcu_read_unlock();
 227 #endif
 228
 229         net->ipv4.sysctl_tcp_mem[0] = vec[0];
 230         net->ipv4.sysctl_tcp_mem[1] = vec[1];
 231         net->ipv4.sysctl_tcp_mem[2] = vec[2];
 232
 233         return 0;
 234 }
 235
 236 static int proc_tcp_fastopen_key(ctl_table *ctl, int write, void __user *buffer,
 237                                  size_t *lenp, loff_t *ppos)
 238 {
 239         ctl_table tbl = { .maxlen = (TCP_FASTOPEN_KEY_LENGTH * 2 + 10) };
 240         struct tcp_fastopen_context *ctxt;
 241         int ret;
 242         u32  user_key[4]; /* 16 bytes, matching TCP_FASTOPEN_KEY_LENGTH */
 243
 244         tbl.data = kmalloc(tbl.maxlen, GFP_KERNEL);
 245         if (!tbl.data)
 246                 return -ENOMEM;
 247
 248         rcu_read_lock();
 249         ctxt = rcu_dereference(tcp_fastopen_ctx);
 250         if (ctxt)
 251                 memcpy(user_key, ctxt->key, TCP_FASTOPEN_KEY_LENGTH);
 252         else
 253                 memset(user_key, 0, sizeof(user_key));
 254         rcu_read_unlock();
 255
 256         snprintf(tbl.data, tbl.maxlen, "%08x-%08x-%08x-%08x",
 257                 user_key[0], user_key[1], user_key[2], user_key[3]);
 258         ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 259
 260         if (write && ret == 0) {
 261                 if (sscanf(tbl.data, "%x-%x-%x-%x", user_key, user_key + 1,
 262                            user_key + 2, user_key + 3) != 4) {
 263                         ret = -EINVAL;
 264                         goto bad_key;
 265                 }
 266                 tcp_fastopen_reset_cipher(user_key, TCP_FASTOPEN_KEY_LENGTH);
 267         }
 268
 269 bad_key:
 270         pr_debug("proc FO key set 0x%x-%x-%x-%x <- 0x%s: %u\n",
 271                user_key[0], user_key[1], user_key[2], user_key[3],
 272                (char *)tbl.data, ret);
 273         kfree(tbl.data);
 274         return ret;
 275 }
 276
 277 static struct ctl_table ipv4_table[] = {
 278         {
 279                 .procname       = "tcp_timestamps",
 280                 .data           = &sysctl_tcp_timestamps,
 281                 .maxlen         = sizeof(int),
 282                 .mode           = 0644,
 283                 .proc_handler   = proc_dointvec
 284         },
 285         {
 286                 .procname       = "tcp_window_scaling",
 287                 .data           = &sysctl_tcp_window_scaling,
 288                 .maxlen         = sizeof(int),
 289                 .mode           = 0644,
 290                 .proc_handler   = proc_dointvec
 291         },
 292         {
 293                 .procname       = "tcp_sack",
 294                 .data           = &sysctl_tcp_sack,
 295                 .maxlen         = sizeof(int),
 296                 .mode           = 0644,
 297                 .proc_handler   = proc_dointvec
 298         },
 299         {
 300                 .procname       = "tcp_retrans_collapse",
 301                 .data           = &sysctl_tcp_retrans_collapse,
 302                 .maxlen         = sizeof(int),
 303                 .mode           = 0644,
 304                 .proc_handler   = proc_dointvec
 305         },
 306         {
 307                 .procname       = "ip_default_ttl",
 308                 .data           = &sysctl_ip_default_ttl,
 309                 .maxlen         = sizeof(int),
 310                 .mode           = 0644,
 311                 .proc_handler   = proc_dointvec_minmax,
 312                 .extra1         = &ip_ttl_min,
 313                 .extra2         = &ip_ttl_max,
 314         },
 315         {
 316                 .procname       = "ip_no_pmtu_disc",
 317                 .data           = &ipv4_config.no_pmtu_disc,
 318                 .maxlen         = sizeof(int),
 319                 .mode           = 0644,
 320                 .proc_handler   = proc_dointvec
 321         },
 322         {
 323                 .procname       = "ip_nonlocal_bind",
 324                 .data           = &sysctl_ip_nonlocal_bind,
 325                 .maxlen         = sizeof(int),
 326                 .mode           = 0644,
 327                 .proc_handler   = proc_dointvec
 328         },
 329         {
 330                 .procname       = "tcp_syn_retries",
 331                 .data           = &sysctl_tcp_syn_retries,
 332                 .maxlen         = sizeof(int),
 333                 .mode           = 0644,
 334                 .proc_handler   = proc_dointvec
 335         },
 336         {
 337                 .procname       = "tcp_synack_retries",
 338                 .data           = &sysctl_tcp_synack_retries,
 339                 .maxlen         = sizeof(int),
 340                 .mode           = 0644,
 341                 .proc_handler   = proc_dointvec
 342         },
 343         {
 344                 .procname       = "tcp_max_orphans",
 345                 .data           = &sysctl_tcp_max_orphans,
 346                 .maxlen         = sizeof(int),
 347                 .mode           = 0644,
 348                 .proc_handler   = proc_dointvec
 349         },
 350         {
 351                 .procname       = "tcp_max_tw_buckets",
 352                 .data           = &tcp_death_row.sysctl_max_tw_buckets,
 353                 .maxlen         = sizeof(int),
 354                 .mode           = 0644,
 355                 .proc_handler   = proc_dointvec
 356         },
 357         {
 358                 .procname       = "ip_early_demux",
 359                 .data           = &sysctl_ip_early_demux,
 360                 .maxlen         = sizeof(int),
 361                 .mode           = 0644,
 362                 .proc_handler   = proc_dointvec
 363         },
 364         {
 365                 .procname       = "ip_dynaddr",
 366                 .data           = &sysctl_ip_dynaddr,
 367                 .maxlen         = sizeof(int),
 368                 .mode           = 0644,
 369                 .proc_handler   = proc_dointvec
 370         },
 371         {
 372                 .procname       = "tcp_keepalive_time",
 373                 .data           = &sysctl_tcp_keepalive_time,
 374                 .maxlen         = sizeof(int),
 375                 .mode           = 0644,
 376                 .proc_handler   = proc_dointvec_jiffies,
 377         },
 378         {
 379                 .procname       = "tcp_keepalive_probes",
 380                 .data           = &sysctl_tcp_keepalive_probes,
 381                 .maxlen         = sizeof(int),
 382                 .mode           = 0644,
 383                 .proc_handler   = proc_dointvec
 384         },
 385         {
 386                 .procname       = "tcp_keepalive_intvl",
 387                 .data           = &sysctl_tcp_keepalive_intvl,
 388                 .maxlen         = sizeof(int),
 389                 .mode           = 0644,
 390                 .proc_handler   = proc_dointvec_jiffies,
 391         },
 392         {
 393                 .procname       = "tcp_retries1",
 394                 .data           = &sysctl_tcp_retries1,
 395                 .maxlen         = sizeof(int),
 396                 .mode           = 0644,
 397                 .proc_handler   = proc_dointvec_minmax,
 398                 .extra2         = &tcp_retr1_max
 399         },
 400         {
 401                 .procname       = "tcp_retries2",
 402                 .data           = &sysctl_tcp_retries2,
 403                 .maxlen         = sizeof(int),
 404                 .mode           = 0644,
 405                 .proc_handler   = proc_dointvec
 406         },
 407         {
 408                 .procname       = "tcp_fin_timeout",
 409                 .data           = &sysctl_tcp_fin_timeout,
 410                 .maxlen         = sizeof(int),
 411                 .mode           = 0644,
 412                 .proc_handler   = proc_dointvec_jiffies,
 413         },
 414 #ifdef CONFIG_SYN_COOKIES
 415         {
 416                 .procname       = "tcp_syncookies",
 417                 .data           = &sysctl_tcp_syncookies,
 418                 .maxlen         = sizeof(int),
 419                 .mode           = 0644,
 420                 .proc_handler   = proc_dointvec
 421         },
 422 #endif
 423         {
 424                 .procname       = "tcp_fastopen",
 425                 .data           = &sysctl_tcp_fastopen,
 426                 .maxlen         = sizeof(int),
 427                 .mode           = 0644,
 428                 .proc_handler   = proc_dointvec,
 429         },
 430         {
 431                 .procname       = "tcp_fastopen_key",
 432                 .mode           = 0600,
 433                 .maxlen         = ((TCP_FASTOPEN_KEY_LENGTH * 2) + 10),
 434                 .proc_handler   = proc_tcp_fastopen_key,
 435         },
 436         {
 437                 .procname       = "tcp_tw_recycle",
 438                 .data           = &tcp_death_row.sysctl_tw_recycle,
 439                 .maxlen         = sizeof(int),
 440                 .mode           = 0644,
 441                 .proc_handler   = proc_dointvec
 442         },
 443         {
 444                 .procname       = "tcp_abort_on_overflow",
 445                 .data           = &sysctl_tcp_abort_on_overflow,
 446                 .maxlen         = sizeof(int),
 447                 .mode           = 0644,
 448                 .proc_handler   = proc_dointvec
 449         },
 450         {
 451                 .procname       = "tcp_stdurg",
 452                 .data           = &sysctl_tcp_stdurg,
 453                 .maxlen         = sizeof(int),
 454                 .mode           = 0644,
 455                 .proc_handler   = proc_dointvec
 456         },
 457         {
 458                 .procname       = "tcp_rfc1337",
 459                 .data           = &sysctl_tcp_rfc1337,
 460                 .maxlen         = sizeof(int),
 461                 .mode           = 0644,
 462                 .proc_handler   = proc_dointvec
 463         },
 464         {
 465                 .procname       = "tcp_max_syn_backlog",
 466                 .data           = &sysctl_max_syn_backlog,
 467                 .maxlen         = sizeof(int),
 468                 .mode           = 0644,
 469                 .proc_handler   = proc_dointvec
 470         },
 471         {
 472                 .procname       = "ip_local_port_range",
 473                 .data           = &sysctl_local_ports.range,
 474                 .maxlen         = sizeof(sysctl_local_ports.range),
 475                 .mode           = 0644,
 476                 .proc_handler   = ipv4_local_port_range,
 477         },
 478         {
 479                 .procname       = "ip_local_reserved_ports",
 480                 .data           = NULL, /* initialized in sysctl_ipv4_init */
 481                 .maxlen         = 65536,
 482                 .mode           = 0644,
 483                 .proc_handler   = proc_do_large_bitmap,
 484         },
 485         {
 486                 .procname       = "igmp_max_memberships",
 487                 .data           = &sysctl_igmp_max_memberships,
 488                 .maxlen         = sizeof(int),
 489                 .mode           = 0644,
 490                 .proc_handler   = proc_dointvec
 491         },
 492         {
 493                 .procname       = "igmp_max_msf",
 494                 .data           = &sysctl_igmp_max_msf,
 495                 .maxlen         = sizeof(int),
 496                 .mode           = 0644,
 497                 .proc_handler   = proc_dointvec
 498         },
 499         {
 500                 .procname       = "inet_peer_threshold",
 501                 .data           = &inet_peer_threshold,
 502                 .maxlen         = sizeof(int),
 503                 .mode           = 0644,
 504                 .proc_handler   = proc_dointvec
 505         },
 506         {
 507                 .procname       = "inet_peer_minttl",
 508                 .data           = &inet_peer_minttl,
 509                 .maxlen         = sizeof(int),
 510                 .mode           = 0644,
 511                 .proc_handler   = proc_dointvec_jiffies,
 512         },
 513         {
 514                 .procname       = "inet_peer_maxttl",
 515                 .data           = &inet_peer_maxttl,
 516                 .maxlen         = sizeof(int),
 517                 .mode           = 0644,
 518                 .proc_handler   = proc_dointvec_jiffies,
 519         },
 520         {
 521                 .procname       = "tcp_orphan_retries",
 522                 .data           = &sysctl_tcp_orphan_retries,
 523                 .maxlen         = sizeof(int),
 524                 .mode           = 0644,
 525                 .proc_handler   = proc_dointvec
 526         },
 527         {
 528                 .procname       = "tcp_fack",
 529                 .data           = &sysctl_tcp_fack,
 530                 .maxlen         = sizeof(int),
 531                 .mode           = 0644,
 532                 .proc_handler   = proc_dointvec
 533         },
 534         {
 535                 .procname       = "tcp_reordering",
 536                 .data           = &sysctl_tcp_reordering,
 537                 .maxlen         = sizeof(int),
 538                 .mode           = 0644,
 539                 .proc_handler   = proc_dointvec
 540         },
 541         {
 542                 .procname       = "tcp_dsack",
 543                 .data           = &sysctl_tcp_dsack,
 544                 .maxlen         = sizeof(int),
 545                 .mode           = 0644,
 546                 .proc_handler   = proc_dointvec
 547         },
 548         {
 549                 .procname       = "tcp_wmem",
 550                 .data           = &sysctl_tcp_wmem,
 551                 .maxlen         = sizeof(sysctl_tcp_wmem),
 552                 .mode           = 0644,
 553                 .proc_handler   = proc_dointvec_minmax,
 554                 .extra1         = &one,
 555         },
 556         {
 557                 .procname       = "tcp_rmem",
 558                 .data           = &sysctl_tcp_rmem,
 559                 .maxlen         = sizeof(sysctl_tcp_rmem),
 560                 .mode           = 0644,
 561                 .proc_handler   = proc_dointvec_minmax,
 562                 .extra1         = &one,
 563         },
 564         {
 565                 .procname       = "tcp_app_win",
 566                 .data           = &sysctl_tcp_app_win,
 567                 .maxlen         = sizeof(int),
 568                 .mode           = 0644,
 569                 .proc_handler   = proc_dointvec
 570         },
 571         {
 572                 .procname       = "tcp_adv_win_scale",
 573                 .data           = &sysctl_tcp_adv_win_scale,
 574                 .maxlen         = sizeof(int),
 575                 .mode           = 0644,
 576                 .proc_handler   = proc_dointvec_minmax,
 577                 .extra1         = &tcp_adv_win_scale_min,
 578                 .extra2         = &tcp_adv_win_scale_max,
 579         },
 580         {
 581                 .procname       = "tcp_tw_reuse",
 582                 .data           = &sysctl_tcp_tw_reuse,
 583                 .maxlen         = sizeof(int),
 584                 .mode           = 0644,
 585                 .proc_handler   = proc_dointvec
 586         },
 587         {
 588                 .procname       = "tcp_frto",
 589                 .data           = &sysctl_tcp_frto,
 590                 .maxlen         = sizeof(int),
 591                 .mode           = 0644,
 592                 .proc_handler   = proc_dointvec
 593         },
 594         {
 595                 .procname       = "tcp_frto_response",
 596                 .data           = &sysctl_tcp_frto_response,
 597                 .maxlen         = sizeof(int),
 598                 .mode           = 0644,
 599                 .proc_handler   = proc_dointvec
 600         },
 601         {
 602                 .procname       = "tcp_low_latency",
 603                 .data           = &sysctl_tcp_low_latency,
 604                 .maxlen         = sizeof(int),
 605                 .mode           = 0644,
 606                 .proc_handler   = proc_dointvec
 607         },
 608         {
 609                 .procname       = "tcp_no_metrics_save",
 610                 .data           = &sysctl_tcp_nometrics_save,
 611                 .maxlen         = sizeof(int),
 612                 .mode           = 0644,
 613                 .proc_handler   = proc_dointvec,
 614         },
 615         {
 616                 .procname       = "tcp_moderate_rcvbuf",
 617                 .data           = &sysctl_tcp_moderate_rcvbuf,
 618                 .maxlen         = sizeof(int),
 619                 .mode           = 0644,
 620                 .proc_handler   = proc_dointvec,
 621         },
 622         {
 623                 .procname       = "tcp_tso_win_divisor",
 624                 .data           = &sysctl_tcp_tso_win_divisor,
 625                 .maxlen         = sizeof(int),
 626                 .mode           = 0644,
 627                 .proc_handler   = proc_dointvec,
 628         },
 629         {
 630                 .procname       = "tcp_congestion_control",
 631                 .mode           = 0644,
 632                 .maxlen         = TCP_CA_NAME_MAX,
 633                 .proc_handler   = proc_tcp_congestion_control,
 634         },
 635         {
 636                 .procname       = "tcp_mtu_probing",
 637                 .data           = &sysctl_tcp_mtu_probing,
 638                 .maxlen         = sizeof(int),
 639                 .mode           = 0644,
 640                 .proc_handler   = proc_dointvec,
 641         },
 642         {
 643                 .procname       = "tcp_base_mss",
 644                 .data           = &sysctl_tcp_base_mss,
 645                 .maxlen         = sizeof(int),
 646                 .mode           = 0644,
 647                 .proc_handler   = proc_dointvec,
 648         },
 649         {
 650                 .procname       = "tcp_workaround_signed_windows",
 651                 .data           = &sysctl_tcp_workaround_signed_windows,
 652                 .maxlen         = sizeof(int),
 653                 .mode           = 0644,
 654                 .proc_handler   = proc_dointvec
 655         },
 656         {
 657                 .procname       = "tcp_limit_output_bytes",
 658                 .data           = &sysctl_tcp_limit_output_bytes,
 659                 .maxlen         = sizeof(int),
 660                 .mode           = 0644,
 661                 .proc_handler   = proc_dointvec
 662         },
 663         {
 664                 .procname       = "tcp_challenge_ack_limit",
 665                 .data           = &sysctl_tcp_challenge_ack_limit,
 666                 .maxlen         = sizeof(int),
 667                 .mode           = 0644,
 668                 .proc_handler   = proc_dointvec
 669         },
 670 #ifdef CONFIG_NET_DMA
 671         {
 672                 .procname       = "tcp_dma_copybreak",
 673                 .data           = &sysctl_tcp_dma_copybreak,
 674                 .maxlen         = sizeof(int),
 675                 .mode           = 0644,
 676                 .proc_handler   = proc_dointvec
 677         },
 678 #endif
 679         {
 680                 .procname       = "tcp_slow_start_after_idle",
 681                 .data           = &sysctl_tcp_slow_start_after_idle,
 682                 .maxlen         = sizeof(int),
 683                 .mode           = 0644,
 684                 .proc_handler   = proc_dointvec
 685         },
 686 #ifdef CONFIG_NETLABEL
 687         {
 688                 .procname       = "cipso_cache_enable",
 689                 .data           = &cipso_v4_cache_enabled,
 690                 .maxlen         = sizeof(int),
 691                 .mode           = 0644,
 692                 .proc_handler   = proc_dointvec,
 693         },
 694         {
 695                 .procname       = "cipso_cache_bucket_size",
 696                 .data           = &cipso_v4_cache_bucketsize,
 697                 .maxlen         = sizeof(int),
 698                 .mode           = 0644,
 699                 .proc_handler   = proc_dointvec,
 700         },
 701         {
 702                 .procname       = "cipso_rbm_optfmt",
 703                 .data           = &cipso_v4_rbm_optfmt,
 704                 .maxlen         = sizeof(int),
 705                 .mode           = 0644,
 706                 .proc_handler   = proc_dointvec,
 707         },
 708         {
 709                 .procname       = "cipso_rbm_strictvalid",
 710                 .data           = &cipso_v4_rbm_strictvalid,
 711                 .maxlen         = sizeof(int),
 712                 .mode           = 0644,
 713                 .proc_handler   = proc_dointvec,
 714         },
 715 #endif /* CONFIG_NETLABEL */
 716         {
 717                 .procname       = "tcp_available_congestion_control",
 718                 .maxlen         = TCP_CA_BUF_MAX,
 719                 .mode           = 0444,
 720                 .proc_handler   = proc_tcp_available_congestion_control,
 721         },
 722         {
 723                 .procname       = "tcp_allowed_congestion_control",
 724                 .maxlen         = TCP_CA_BUF_MAX,
 725                 .mode           = 0644,
 726                 .proc_handler   = proc_allowed_congestion_control,
 727         },
 728         {
 729                 .procname       = "tcp_max_ssthresh",
 730                 .data           = &sysctl_tcp_max_ssthresh,
 731                 .maxlen         = sizeof(int),
 732                 .mode           = 0644,
 733                 .proc_handler   = proc_dointvec,
 734         },
 735         {
 736                 .procname       = "tcp_cookie_size",
 737                 .data           = &sysctl_tcp_cookie_size,
 738                 .maxlen         = sizeof(int),
 739                 .mode           = 0644,
 740                 .proc_handler   = proc_dointvec
 741         },
 742         {
 743                 .procname       = "tcp_thin_linear_timeouts",
 744                 .data           = &sysctl_tcp_thin_linear_timeouts,
 745                 .maxlen         = sizeof(int),
 746                 .mode           = 0644,
 747                 .proc_handler   = proc_dointvec
 748         },
 749         {
 750                 .procname       = "tcp_thin_dupack",
 751                 .data           = &sysctl_tcp_thin_dupack,
 752                 .maxlen         = sizeof(int),
 753                 .mode           = 0644,
 754                 .proc_handler   = proc_dointvec
 755         },
 756         {
 757                 .procname       = "tcp_early_retrans",
 758                 .data           = &sysctl_tcp_early_retrans,
 759                 .maxlen         = sizeof(int),
 760                 .mode           = 0644,
 761                 .proc_handler   = proc_dointvec_minmax,
 762                 .extra1         = &zero,
 763                 .extra2         = &two,
 764         },
 765         {
 766                 .procname       = "udp_mem",
 767                 .data           = &sysctl_udp_mem,
 768                 .maxlen         = sizeof(sysctl_udp_mem),
 769                 .mode           = 0644,
 770                 .proc_handler   = proc_doulongvec_minmax,
 771         },
 772         {
 773                 .procname       = "udp_rmem_min",
 774                 .data           = &sysctl_udp_rmem_min,
 775                 .maxlen         = sizeof(sysctl_udp_rmem_min),
 776                 .mode           = 0644,
 777                 .proc_handler   = proc_dointvec_minmax,
 778                 .extra1         = &one
 779         },
 780         {
 781                 .procname       = "udp_wmem_min",
 782                 .data           = &sysctl_udp_wmem_min,
 783                 .maxlen         = sizeof(sysctl_udp_wmem_min),
 784                 .mode           = 0644,
 785                 .proc_handler   = proc_dointvec_minmax,
 786                 .extra1         = &one
 787         },
 788         { }
 789 };
 790
 791 static struct ctl_table ipv4_net_table[] = {
 792         {
 793                 .procname       = "icmp_echo_ignore_all",
 794                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_all,
 795                 .maxlen         = sizeof(int),
 796                 .mode           = 0644,
 797                 .proc_handler   = proc_dointvec
 798         },
 799         {
 800                 .procname       = "icmp_echo_ignore_broadcasts",
 801                 .data           = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts,
 802                 .maxlen         = sizeof(int),
 803                 .mode           = 0644,
 804                 .proc_handler   = proc_dointvec
 805         },
 806         {
 807                 .procname       = "icmp_ignore_bogus_error_responses",
 808                 .data           = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses,
 809                 .maxlen         = sizeof(int),
 810                 .mode           = 0644,
 811                 .proc_handler   = proc_dointvec
 812         },
 813         {
 814                 .procname       = "icmp_errors_use_inbound_ifaddr",
 815                 .data           = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr,
 816                 .maxlen         = sizeof(int),
 817                 .mode           = 0644,
 818                 .proc_handler   = proc_dointvec
 819         },
 820         {
 821                 .procname       = "icmp_ratelimit",
 822                 .data           = &init_net.ipv4.sysctl_icmp_ratelimit,
 823                 .maxlen         = sizeof(int),
 824                 .mode           = 0644,
 825                 .proc_handler   = proc_dointvec_ms_jiffies,
 826         },
 827         {
 828                 .procname       = "icmp_ratemask",
 829                 .data           = &init_net.ipv4.sysctl_icmp_ratemask,
 830                 .maxlen         = sizeof(int),
 831                 .mode           = 0644,
 832                 .proc_handler   = proc_dointvec
 833         },
 834         {
 835                 .procname       = "ping_group_range",
 836                 .data           = &init_net.ipv4.sysctl_ping_group_range,
 837                 .maxlen         = sizeof(gid_t)*2,
 838                 .mode           = 0644,
 839                 .proc_handler   = ipv4_ping_group_range,
 840         },
 841         {
 842                 .procname       = "tcp_ecn",
 843                 .data           = &init_net.ipv4.sysctl_tcp_ecn,
 844                 .maxlen         = sizeof(int),
 845                 .mode           = 0644,
 846                 .proc_handler   = proc_dointvec
 847         },
 848         {
 849                 .procname       = "tcp_mem",
 850                 .maxlen         = sizeof(init_net.ipv4.sysctl_tcp_mem),
 851                 .mode           = 0644,
 852                 .proc_handler   = ipv4_tcp_mem,
 853         },
 854         { }
 855 };
 856
 857 static __net_init int ipv4_sysctl_init_net(struct net *net)
 858 {
 859         struct ctl_table *table;
 860
 861         table = ipv4_net_table;
 862         if (!net_eq(net, &init_net)) {
 863                 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL);
 864                 if (table == NULL)
 865                         goto err_alloc;
 866
 867                 table[0].data =
 868                         &net->ipv4.sysctl_icmp_echo_ignore_all;
 869                 table[1].data =
 870                         &net->ipv4.sysctl_icmp_echo_ignore_broadcasts;
 871                 table[2].data =
 872                         &net->ipv4.sysctl_icmp_ignore_bogus_error_responses;
 873                 table[3].data =
 874                         &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr;
 875                 table[4].data =
 876                         &net->ipv4.sysctl_icmp_ratelimit;
 877                 table[5].data =
 878                         &net->ipv4.sysctl_icmp_ratemask;
 879                 table[6].data =
 880                         &net->ipv4.sysctl_ping_group_range;
 881                 table[7].data =
 882                         &net->ipv4.sysctl_tcp_ecn;
 883
 884                 /* Don't export sysctls to unprivileged users */
 885                 if (net->user_ns != &init_user_ns)
 886                         table[0].procname = NULL;
 887         }
 888
 889         /*
 890          * Sane defaults - nobody may create ping sockets.
 891          * Boot scripts should set this to distro-specific group.
 892          */
 893         net->ipv4.sysctl_ping_group_range[0] = make_kgid(&init_user_ns, 1);
 894         net->ipv4.sysctl_ping_group_range[1] = make_kgid(&init_user_ns, 0);
 895
 896         tcp_init_mem(net);
 897
 898         net->ipv4.ipv4_hdr = register_net_sysctl(net, "net/ipv4", table);
 899         if (net->ipv4.ipv4_hdr == NULL)
 900                 goto err_reg;
 901
 902         return 0;
 903
 904 err_reg:
 905         if (!net_eq(net, &init_net))
 906                 kfree(table);
 907 err_alloc:
 908         return -ENOMEM;
 909 }
 910
 911 static __net_exit void ipv4_sysctl_exit_net(struct net *net)
 912 {
 913         struct ctl_table *table;
 914
 915         table = net->ipv4.ipv4_hdr->ctl_table_arg;
 916         unregister_net_sysctl_table(net->ipv4.ipv4_hdr);
 917         kfree(table);
 918 }
 919
 920 static __net_initdata struct pernet_operations ipv4_sysctl_ops = {
 921         .init = ipv4_sysctl_init_net,
 922         .exit = ipv4_sysctl_exit_net,
 923 };
 924
 925 static __init int sysctl_ipv4_init(void)
 926 {
 927         struct ctl_table_header *hdr;
 928         struct ctl_table *i;
 929
 930         for (i = ipv4_table; i->procname; i++) {
 931                 if (strcmp(i->procname, "ip_local_reserved_ports") == 0) {
 932                         i->data = sysctl_local_reserved_ports;
 933                         break;
 934                 }
 935         }
 936         if (!i->procname)
 937                 return -EINVAL;
 938
 939         hdr = register_net_sysctl(&init_net, "net/ipv4", ipv4_table);
 940         if (hdr == NULL)
 941                 return -ENOMEM;
 942
 943         if (register_pernet_subsys(&ipv4_sysctl_ops)) {
 944                 unregister_net_sysctl_table(hdr);
 945                 return -ENOMEM;
 946         }
 947
 948         return 0;
 949 }
 950
 951 __initcall(sysctl_ipv4_init);