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 <net/snmp.h> 17 #include <net/icmp.h> 18 #include <net/ip.h> 19 #include <net/route.h> 20 #include <net/tcp.h> 21 #include <net/udp.h> 22 #include <net/cipso_ipv4.h> 23 #include <net/inet_frag.h> 24 25 static int zero; 26 static int tcp_retr1_max = 255; 27 static int ip_local_port_range_min[] = { 1, 1 }; 28 static int ip_local_port_range_max[] = { 65535, 65535 }; 29 static int tcp_adv_win_scale_min = -31; 30 static int tcp_adv_win_scale_max = 31; 31 static int ip_ttl_min = 1; 32 static int ip_ttl_max = 255; 33 34 /* Update system visible IP port range */ 35 static void set_local_port_range(int range[2]) 36 { 37 write_seqlock(&sysctl_local_ports.lock); 38 sysctl_local_ports.range[0] = range[0]; 39 sysctl_local_ports.range[1] = range[1]; 40 write_sequnlock(&sysctl_local_ports.lock); 41 } 42 43 /* Validate changes from /proc interface. */ 44 static int ipv4_local_port_range(ctl_table *table, int write, 45 void __user *buffer, 46 size_t *lenp, loff_t *ppos) 47 { 48 int ret; 49 int range[2]; 50 ctl_table tmp = { 51 .data = &range, 52 .maxlen = sizeof(range), 53 .mode = table->mode, 54 .extra1 = &ip_local_port_range_min, 55 .extra2 = &ip_local_port_range_max, 56 }; 57 58 inet_get_local_port_range(range, range + 1); 59 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 60 61 if (write && ret == 0) { 62 if (range[1] < range[0]) 63 ret = -EINVAL; 64 else 65 set_local_port_range(range); 66 } 67 68 return ret; 69 } 70 71 static int proc_tcp_congestion_control(ctl_table *ctl, int write, 72 void __user *buffer, size_t *lenp, loff_t *ppos) 73 { 74 char val[TCP_CA_NAME_MAX]; 75 ctl_table tbl = { 76 .data = val, 77 .maxlen = TCP_CA_NAME_MAX, 78 }; 79 int ret; 80 81 tcp_get_default_congestion_control(val); 82 83 ret = proc_dostring(&tbl, write, buffer, lenp, ppos); 84 if (write && ret == 0) 85 ret = tcp_set_default_congestion_control(val); 86 return ret; 87 } 88 89 static int proc_tcp_available_congestion_control(ctl_table *ctl, 90 int write, 91 void __user *buffer, size_t *lenp, 92 loff_t *ppos) 93 { 94 ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX, }; 95 int ret; 96 97 tbl.data = kmalloc(tbl.maxlen, GFP_USER); 98 if (!tbl.data) 99 return -ENOMEM; 100 tcp_get_available_congestion_control(tbl.data, TCP_CA_BUF_MAX); 101 ret = proc_dostring(&tbl, write, buffer, lenp, ppos); 102 kfree(tbl.data); 103 return ret; 104 } 105 106 static int proc_allowed_congestion_control(ctl_table *ctl, 107 int write, 108 void __user *buffer, size_t *lenp, 109 loff_t *ppos) 110 { 111 ctl_table tbl = { .maxlen = TCP_CA_BUF_MAX }; 112 int ret; 113 114 tbl.data = kmalloc(tbl.maxlen, GFP_USER); 115 if (!tbl.data) 116 return -ENOMEM; 117 118 tcp_get_allowed_congestion_control(tbl.data, tbl.maxlen); 119 ret = proc_dostring(&tbl, write, buffer, lenp, ppos); 120 if (write && ret == 0) 121 ret = tcp_set_allowed_congestion_control(tbl.data); 122 kfree(tbl.data); 123 return ret; 124 } 125 126 static struct ctl_table ipv4_table[] = { 127 { 128 .procname = "tcp_timestamps", 129 .data = &sysctl_tcp_timestamps, 130 .maxlen = sizeof(int), 131 .mode = 0644, 132 .proc_handler = proc_dointvec 133 }, 134 { 135 .procname = "tcp_window_scaling", 136 .data = &sysctl_tcp_window_scaling, 137 .maxlen = sizeof(int), 138 .mode = 0644, 139 .proc_handler = proc_dointvec 140 }, 141 { 142 .procname = "tcp_sack", 143 .data = &sysctl_tcp_sack, 144 .maxlen = sizeof(int), 145 .mode = 0644, 146 .proc_handler = proc_dointvec 147 }, 148 { 149 .procname = "tcp_retrans_collapse", 150 .data = &sysctl_tcp_retrans_collapse, 151 .maxlen = sizeof(int), 152 .mode = 0644, 153 .proc_handler = proc_dointvec 154 }, 155 { 156 .procname = "ip_default_ttl", 157 .data = &sysctl_ip_default_ttl, 158 .maxlen = sizeof(int), 159 .mode = 0644, 160 .proc_handler = proc_dointvec_minmax, 161 .extra1 = &ip_ttl_min, 162 .extra2 = &ip_ttl_max, 163 }, 164 { 165 .procname = "ip_no_pmtu_disc", 166 .data = &ipv4_config.no_pmtu_disc, 167 .maxlen = sizeof(int), 168 .mode = 0644, 169 .proc_handler = proc_dointvec 170 }, 171 { 172 .procname = "ip_nonlocal_bind", 173 .data = &sysctl_ip_nonlocal_bind, 174 .maxlen = sizeof(int), 175 .mode = 0644, 176 .proc_handler = proc_dointvec 177 }, 178 { 179 .procname = "tcp_syn_retries", 180 .data = &sysctl_tcp_syn_retries, 181 .maxlen = sizeof(int), 182 .mode = 0644, 183 .proc_handler = proc_dointvec 184 }, 185 { 186 .procname = "tcp_synack_retries", 187 .data = &sysctl_tcp_synack_retries, 188 .maxlen = sizeof(int), 189 .mode = 0644, 190 .proc_handler = proc_dointvec 191 }, 192 { 193 .procname = "tcp_max_orphans", 194 .data = &sysctl_tcp_max_orphans, 195 .maxlen = sizeof(int), 196 .mode = 0644, 197 .proc_handler = proc_dointvec 198 }, 199 { 200 .procname = "tcp_max_tw_buckets", 201 .data = &tcp_death_row.sysctl_max_tw_buckets, 202 .maxlen = sizeof(int), 203 .mode = 0644, 204 .proc_handler = proc_dointvec 205 }, 206 { 207 .procname = "ip_dynaddr", 208 .data = &sysctl_ip_dynaddr, 209 .maxlen = sizeof(int), 210 .mode = 0644, 211 .proc_handler = proc_dointvec 212 }, 213 { 214 .procname = "tcp_keepalive_time", 215 .data = &sysctl_tcp_keepalive_time, 216 .maxlen = sizeof(int), 217 .mode = 0644, 218 .proc_handler = proc_dointvec_jiffies, 219 }, 220 { 221 .procname = "tcp_keepalive_probes", 222 .data = &sysctl_tcp_keepalive_probes, 223 .maxlen = sizeof(int), 224 .mode = 0644, 225 .proc_handler = proc_dointvec 226 }, 227 { 228 .procname = "tcp_keepalive_intvl", 229 .data = &sysctl_tcp_keepalive_intvl, 230 .maxlen = sizeof(int), 231 .mode = 0644, 232 .proc_handler = proc_dointvec_jiffies, 233 }, 234 { 235 .procname = "tcp_retries1", 236 .data = &sysctl_tcp_retries1, 237 .maxlen = sizeof(int), 238 .mode = 0644, 239 .proc_handler = proc_dointvec_minmax, 240 .extra2 = &tcp_retr1_max 241 }, 242 { 243 .procname = "tcp_retries2", 244 .data = &sysctl_tcp_retries2, 245 .maxlen = sizeof(int), 246 .mode = 0644, 247 .proc_handler = proc_dointvec 248 }, 249 { 250 .procname = "tcp_fin_timeout", 251 .data = &sysctl_tcp_fin_timeout, 252 .maxlen = sizeof(int), 253 .mode = 0644, 254 .proc_handler = proc_dointvec_jiffies, 255 }, 256 #ifdef CONFIG_SYN_COOKIES 257 { 258 .procname = "tcp_syncookies", 259 .data = &sysctl_tcp_syncookies, 260 .maxlen = sizeof(int), 261 .mode = 0644, 262 .proc_handler = proc_dointvec 263 }, 264 #endif 265 { 266 .procname = "tcp_tw_recycle", 267 .data = &tcp_death_row.sysctl_tw_recycle, 268 .maxlen = sizeof(int), 269 .mode = 0644, 270 .proc_handler = proc_dointvec 271 }, 272 { 273 .procname = "tcp_abort_on_overflow", 274 .data = &sysctl_tcp_abort_on_overflow, 275 .maxlen = sizeof(int), 276 .mode = 0644, 277 .proc_handler = proc_dointvec 278 }, 279 { 280 .procname = "tcp_stdurg", 281 .data = &sysctl_tcp_stdurg, 282 .maxlen = sizeof(int), 283 .mode = 0644, 284 .proc_handler = proc_dointvec 285 }, 286 { 287 .procname = "tcp_rfc1337", 288 .data = &sysctl_tcp_rfc1337, 289 .maxlen = sizeof(int), 290 .mode = 0644, 291 .proc_handler = proc_dointvec 292 }, 293 { 294 .procname = "tcp_max_syn_backlog", 295 .data = &sysctl_max_syn_backlog, 296 .maxlen = sizeof(int), 297 .mode = 0644, 298 .proc_handler = proc_dointvec 299 }, 300 { 301 .procname = "ip_local_port_range", 302 .data = &sysctl_local_ports.range, 303 .maxlen = sizeof(sysctl_local_ports.range), 304 .mode = 0644, 305 .proc_handler = ipv4_local_port_range, 306 }, 307 { 308 .procname = "ip_local_reserved_ports", 309 .data = NULL, /* initialized in sysctl_ipv4_init */ 310 .maxlen = 65536, 311 .mode = 0644, 312 .proc_handler = proc_do_large_bitmap, 313 }, 314 { 315 .procname = "igmp_max_memberships", 316 .data = &sysctl_igmp_max_memberships, 317 .maxlen = sizeof(int), 318 .mode = 0644, 319 .proc_handler = proc_dointvec 320 }, 321 { 322 .procname = "igmp_max_msf", 323 .data = &sysctl_igmp_max_msf, 324 .maxlen = sizeof(int), 325 .mode = 0644, 326 .proc_handler = proc_dointvec 327 }, 328 { 329 .procname = "inet_peer_threshold", 330 .data = &inet_peer_threshold, 331 .maxlen = sizeof(int), 332 .mode = 0644, 333 .proc_handler = proc_dointvec 334 }, 335 { 336 .procname = "inet_peer_minttl", 337 .data = &inet_peer_minttl, 338 .maxlen = sizeof(int), 339 .mode = 0644, 340 .proc_handler = proc_dointvec_jiffies, 341 }, 342 { 343 .procname = "inet_peer_maxttl", 344 .data = &inet_peer_maxttl, 345 .maxlen = sizeof(int), 346 .mode = 0644, 347 .proc_handler = proc_dointvec_jiffies, 348 }, 349 { 350 .procname = "inet_peer_gc_mintime", 351 .data = &inet_peer_gc_mintime, 352 .maxlen = sizeof(int), 353 .mode = 0644, 354 .proc_handler = proc_dointvec_jiffies, 355 }, 356 { 357 .procname = "inet_peer_gc_maxtime", 358 .data = &inet_peer_gc_maxtime, 359 .maxlen = sizeof(int), 360 .mode = 0644, 361 .proc_handler = proc_dointvec_jiffies, 362 }, 363 { 364 .procname = "tcp_orphan_retries", 365 .data = &sysctl_tcp_orphan_retries, 366 .maxlen = sizeof(int), 367 .mode = 0644, 368 .proc_handler = proc_dointvec 369 }, 370 { 371 .procname = "tcp_fack", 372 .data = &sysctl_tcp_fack, 373 .maxlen = sizeof(int), 374 .mode = 0644, 375 .proc_handler = proc_dointvec 376 }, 377 { 378 .procname = "tcp_reordering", 379 .data = &sysctl_tcp_reordering, 380 .maxlen = sizeof(int), 381 .mode = 0644, 382 .proc_handler = proc_dointvec 383 }, 384 { 385 .procname = "tcp_ecn", 386 .data = &sysctl_tcp_ecn, 387 .maxlen = sizeof(int), 388 .mode = 0644, 389 .proc_handler = proc_dointvec 390 }, 391 { 392 .procname = "tcp_dsack", 393 .data = &sysctl_tcp_dsack, 394 .maxlen = sizeof(int), 395 .mode = 0644, 396 .proc_handler = proc_dointvec 397 }, 398 { 399 .procname = "tcp_mem", 400 .data = &sysctl_tcp_mem, 401 .maxlen = sizeof(sysctl_tcp_mem), 402 .mode = 0644, 403 .proc_handler = proc_doulongvec_minmax 404 }, 405 { 406 .procname = "tcp_wmem", 407 .data = &sysctl_tcp_wmem, 408 .maxlen = sizeof(sysctl_tcp_wmem), 409 .mode = 0644, 410 .proc_handler = proc_dointvec 411 }, 412 { 413 .procname = "tcp_rmem", 414 .data = &sysctl_tcp_rmem, 415 .maxlen = sizeof(sysctl_tcp_rmem), 416 .mode = 0644, 417 .proc_handler = proc_dointvec 418 }, 419 { 420 .procname = "tcp_app_win", 421 .data = &sysctl_tcp_app_win, 422 .maxlen = sizeof(int), 423 .mode = 0644, 424 .proc_handler = proc_dointvec 425 }, 426 { 427 .procname = "tcp_adv_win_scale", 428 .data = &sysctl_tcp_adv_win_scale, 429 .maxlen = sizeof(int), 430 .mode = 0644, 431 .proc_handler = proc_dointvec_minmax, 432 .extra1 = &tcp_adv_win_scale_min, 433 .extra2 = &tcp_adv_win_scale_max, 434 }, 435 { 436 .procname = "tcp_tw_reuse", 437 .data = &sysctl_tcp_tw_reuse, 438 .maxlen = sizeof(int), 439 .mode = 0644, 440 .proc_handler = proc_dointvec 441 }, 442 { 443 .procname = "tcp_frto", 444 .data = &sysctl_tcp_frto, 445 .maxlen = sizeof(int), 446 .mode = 0644, 447 .proc_handler = proc_dointvec 448 }, 449 { 450 .procname = "tcp_frto_response", 451 .data = &sysctl_tcp_frto_response, 452 .maxlen = sizeof(int), 453 .mode = 0644, 454 .proc_handler = proc_dointvec 455 }, 456 { 457 .procname = "tcp_low_latency", 458 .data = &sysctl_tcp_low_latency, 459 .maxlen = sizeof(int), 460 .mode = 0644, 461 .proc_handler = proc_dointvec 462 }, 463 { 464 .procname = "tcp_no_metrics_save", 465 .data = &sysctl_tcp_nometrics_save, 466 .maxlen = sizeof(int), 467 .mode = 0644, 468 .proc_handler = proc_dointvec, 469 }, 470 { 471 .procname = "tcp_moderate_rcvbuf", 472 .data = &sysctl_tcp_moderate_rcvbuf, 473 .maxlen = sizeof(int), 474 .mode = 0644, 475 .proc_handler = proc_dointvec, 476 }, 477 { 478 .procname = "tcp_tso_win_divisor", 479 .data = &sysctl_tcp_tso_win_divisor, 480 .maxlen = sizeof(int), 481 .mode = 0644, 482 .proc_handler = proc_dointvec, 483 }, 484 { 485 .procname = "tcp_congestion_control", 486 .mode = 0644, 487 .maxlen = TCP_CA_NAME_MAX, 488 .proc_handler = proc_tcp_congestion_control, 489 }, 490 { 491 .procname = "tcp_abc", 492 .data = &sysctl_tcp_abc, 493 .maxlen = sizeof(int), 494 .mode = 0644, 495 .proc_handler = proc_dointvec, 496 }, 497 { 498 .procname = "tcp_mtu_probing", 499 .data = &sysctl_tcp_mtu_probing, 500 .maxlen = sizeof(int), 501 .mode = 0644, 502 .proc_handler = proc_dointvec, 503 }, 504 { 505 .procname = "tcp_base_mss", 506 .data = &sysctl_tcp_base_mss, 507 .maxlen = sizeof(int), 508 .mode = 0644, 509 .proc_handler = proc_dointvec, 510 }, 511 { 512 .procname = "tcp_workaround_signed_windows", 513 .data = &sysctl_tcp_workaround_signed_windows, 514 .maxlen = sizeof(int), 515 .mode = 0644, 516 .proc_handler = proc_dointvec 517 }, 518 #ifdef CONFIG_NET_DMA 519 { 520 .procname = "tcp_dma_copybreak", 521 .data = &sysctl_tcp_dma_copybreak, 522 .maxlen = sizeof(int), 523 .mode = 0644, 524 .proc_handler = proc_dointvec 525 }, 526 #endif 527 { 528 .procname = "tcp_slow_start_after_idle", 529 .data = &sysctl_tcp_slow_start_after_idle, 530 .maxlen = sizeof(int), 531 .mode = 0644, 532 .proc_handler = proc_dointvec 533 }, 534 #ifdef CONFIG_NETLABEL 535 { 536 .procname = "cipso_cache_enable", 537 .data = &cipso_v4_cache_enabled, 538 .maxlen = sizeof(int), 539 .mode = 0644, 540 .proc_handler = proc_dointvec, 541 }, 542 { 543 .procname = "cipso_cache_bucket_size", 544 .data = &cipso_v4_cache_bucketsize, 545 .maxlen = sizeof(int), 546 .mode = 0644, 547 .proc_handler = proc_dointvec, 548 }, 549 { 550 .procname = "cipso_rbm_optfmt", 551 .data = &cipso_v4_rbm_optfmt, 552 .maxlen = sizeof(int), 553 .mode = 0644, 554 .proc_handler = proc_dointvec, 555 }, 556 { 557 .procname = "cipso_rbm_strictvalid", 558 .data = &cipso_v4_rbm_strictvalid, 559 .maxlen = sizeof(int), 560 .mode = 0644, 561 .proc_handler = proc_dointvec, 562 }, 563 #endif /* CONFIG_NETLABEL */ 564 { 565 .procname = "tcp_available_congestion_control", 566 .maxlen = TCP_CA_BUF_MAX, 567 .mode = 0444, 568 .proc_handler = proc_tcp_available_congestion_control, 569 }, 570 { 571 .procname = "tcp_allowed_congestion_control", 572 .maxlen = TCP_CA_BUF_MAX, 573 .mode = 0644, 574 .proc_handler = proc_allowed_congestion_control, 575 }, 576 { 577 .procname = "tcp_max_ssthresh", 578 .data = &sysctl_tcp_max_ssthresh, 579 .maxlen = sizeof(int), 580 .mode = 0644, 581 .proc_handler = proc_dointvec, 582 }, 583 { 584 .procname = "tcp_cookie_size", 585 .data = &sysctl_tcp_cookie_size, 586 .maxlen = sizeof(int), 587 .mode = 0644, 588 .proc_handler = proc_dointvec 589 }, 590 { 591 .procname = "tcp_thin_linear_timeouts", 592 .data = &sysctl_tcp_thin_linear_timeouts, 593 .maxlen = sizeof(int), 594 .mode = 0644, 595 .proc_handler = proc_dointvec 596 }, 597 { 598 .procname = "tcp_thin_dupack", 599 .data = &sysctl_tcp_thin_dupack, 600 .maxlen = sizeof(int), 601 .mode = 0644, 602 .proc_handler = proc_dointvec 603 }, 604 { 605 .procname = "udp_mem", 606 .data = &sysctl_udp_mem, 607 .maxlen = sizeof(sysctl_udp_mem), 608 .mode = 0644, 609 .proc_handler = proc_doulongvec_minmax, 610 }, 611 { 612 .procname = "udp_rmem_min", 613 .data = &sysctl_udp_rmem_min, 614 .maxlen = sizeof(sysctl_udp_rmem_min), 615 .mode = 0644, 616 .proc_handler = proc_dointvec_minmax, 617 .extra1 = &zero 618 }, 619 { 620 .procname = "udp_wmem_min", 621 .data = &sysctl_udp_wmem_min, 622 .maxlen = sizeof(sysctl_udp_wmem_min), 623 .mode = 0644, 624 .proc_handler = proc_dointvec_minmax, 625 .extra1 = &zero 626 }, 627 { } 628 }; 629 630 static struct ctl_table ipv4_net_table[] = { 631 { 632 .procname = "icmp_echo_ignore_all", 633 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_all, 634 .maxlen = sizeof(int), 635 .mode = 0644, 636 .proc_handler = proc_dointvec 637 }, 638 { 639 .procname = "icmp_echo_ignore_broadcasts", 640 .data = &init_net.ipv4.sysctl_icmp_echo_ignore_broadcasts, 641 .maxlen = sizeof(int), 642 .mode = 0644, 643 .proc_handler = proc_dointvec 644 }, 645 { 646 .procname = "icmp_ignore_bogus_error_responses", 647 .data = &init_net.ipv4.sysctl_icmp_ignore_bogus_error_responses, 648 .maxlen = sizeof(int), 649 .mode = 0644, 650 .proc_handler = proc_dointvec 651 }, 652 { 653 .procname = "icmp_errors_use_inbound_ifaddr", 654 .data = &init_net.ipv4.sysctl_icmp_errors_use_inbound_ifaddr, 655 .maxlen = sizeof(int), 656 .mode = 0644, 657 .proc_handler = proc_dointvec 658 }, 659 { 660 .procname = "icmp_ratelimit", 661 .data = &init_net.ipv4.sysctl_icmp_ratelimit, 662 .maxlen = sizeof(int), 663 .mode = 0644, 664 .proc_handler = proc_dointvec_ms_jiffies, 665 }, 666 { 667 .procname = "icmp_ratemask", 668 .data = &init_net.ipv4.sysctl_icmp_ratemask, 669 .maxlen = sizeof(int), 670 .mode = 0644, 671 .proc_handler = proc_dointvec 672 }, 673 { 674 .procname = "rt_cache_rebuild_count", 675 .data = &init_net.ipv4.sysctl_rt_cache_rebuild_count, 676 .maxlen = sizeof(int), 677 .mode = 0644, 678 .proc_handler = proc_dointvec 679 }, 680 { } 681 }; 682 683 struct ctl_path net_ipv4_ctl_path[] = { 684 { .procname = "net", }, 685 { .procname = "ipv4", }, 686 { }, 687 }; 688 EXPORT_SYMBOL_GPL(net_ipv4_ctl_path); 689 690 static __net_init int ipv4_sysctl_init_net(struct net *net) 691 { 692 struct ctl_table *table; 693 694 table = ipv4_net_table; 695 if (!net_eq(net, &init_net)) { 696 table = kmemdup(table, sizeof(ipv4_net_table), GFP_KERNEL); 697 if (table == NULL) 698 goto err_alloc; 699 700 table[0].data = 701 &net->ipv4.sysctl_icmp_echo_ignore_all; 702 table[1].data = 703 &net->ipv4.sysctl_icmp_echo_ignore_broadcasts; 704 table[2].data = 705 &net->ipv4.sysctl_icmp_ignore_bogus_error_responses; 706 table[3].data = 707 &net->ipv4.sysctl_icmp_errors_use_inbound_ifaddr; 708 table[4].data = 709 &net->ipv4.sysctl_icmp_ratelimit; 710 table[5].data = 711 &net->ipv4.sysctl_icmp_ratemask; 712 table[6].data = 713 &net->ipv4.sysctl_rt_cache_rebuild_count; 714 } 715 716 net->ipv4.sysctl_rt_cache_rebuild_count = 4; 717 718 net->ipv4.ipv4_hdr = register_net_sysctl_table(net, 719 net_ipv4_ctl_path, table); 720 if (net->ipv4.ipv4_hdr == NULL) 721 goto err_reg; 722 723 return 0; 724 725 err_reg: 726 if (!net_eq(net, &init_net)) 727 kfree(table); 728 err_alloc: 729 return -ENOMEM; 730 } 731 732 static __net_exit void ipv4_sysctl_exit_net(struct net *net) 733 { 734 struct ctl_table *table; 735 736 table = net->ipv4.ipv4_hdr->ctl_table_arg; 737 unregister_net_sysctl_table(net->ipv4.ipv4_hdr); 738 kfree(table); 739 } 740 741 static __net_initdata struct pernet_operations ipv4_sysctl_ops = { 742 .init = ipv4_sysctl_init_net, 743 .exit = ipv4_sysctl_exit_net, 744 }; 745 746 static __init int sysctl_ipv4_init(void) 747 { 748 struct ctl_table_header *hdr; 749 struct ctl_table *i; 750 751 for (i = ipv4_table; i->procname; i++) { 752 if (strcmp(i->procname, "ip_local_reserved_ports") == 0) { 753 i->data = sysctl_local_reserved_ports; 754 break; 755 } 756 } 757 if (!i->procname) 758 return -EINVAL; 759 760 hdr = register_sysctl_paths(net_ipv4_ctl_path, ipv4_table); 761 if (hdr == NULL) 762 return -ENOMEM; 763 764 if (register_pernet_subsys(&ipv4_sysctl_ops)) { 765 unregister_sysctl_table(hdr); 766 return -ENOMEM; 767 } 768 769 return 0; 770 } 771 772 __initcall(sysctl_ipv4_init); 773