1 // SPDX-License-Identifier: GPL-2.0 2 /* -*- linux-c -*- 3 * sysctl_net_core.c: sysctl interface to net core subsystem. 4 * 5 * Begun April 1, 1996, Mike Shaver. 6 * Added /proc/sys/net/core directory entry (empty =) ). [MS] 7 */ 8 9 #include <linux/filter.h> 10 #include <linux/mm.h> 11 #include <linux/sysctl.h> 12 #include <linux/module.h> 13 #include <linux/socket.h> 14 #include <linux/netdevice.h> 15 #include <linux/ratelimit.h> 16 #include <linux/vmalloc.h> 17 #include <linux/init.h> 18 #include <linux/slab.h> 19 #include <linux/sched/isolation.h> 20 21 #include <net/ip.h> 22 #include <net/sock.h> 23 #include <net/net_ratelimit.h> 24 #include <net/busy_poll.h> 25 #include <net/pkt_sched.h> 26 #include <net/hotdata.h> 27 #include <net/proto_memory.h> 28 #include <net/rps.h> 29 30 #include "dev.h" 31 32 static int int_3600 = 3600; 33 static int min_sndbuf = SOCK_MIN_SNDBUF; 34 static int min_rcvbuf = SOCK_MIN_RCVBUF; 35 static int max_skb_frags = MAX_SKB_FRAGS; 36 static int min_mem_pcpu_rsv = SK_MEMORY_PCPU_RESERVE; 37 static int netdev_budget_usecs_min = 2 * USEC_PER_SEC / HZ; 38 39 static int net_msg_warn; /* Unused, but still a sysctl */ 40 41 int sysctl_fb_tunnels_only_for_init_net __read_mostly = 0; 42 EXPORT_SYMBOL(sysctl_fb_tunnels_only_for_init_net); 43 44 /* 0 - Keep current behavior: 45 * IPv4: inherit all current settings from init_net 46 * IPv6: reset all settings to default 47 * 1 - Both inherit all current settings from init_net 48 * 2 - Both reset all settings to default 49 * 3 - Both inherit all settings from current netns 50 */ 51 int sysctl_devconf_inherit_init_net __read_mostly; 52 EXPORT_SYMBOL(sysctl_devconf_inherit_init_net); 53 54 #if IS_ENABLED(CONFIG_NET_FLOW_LIMIT) || IS_ENABLED(CONFIG_RPS) 55 static int dump_cpumask(void *buffer, size_t *lenp, loff_t *ppos, 56 struct cpumask *mask) 57 { 58 char *kbuf; 59 int len; 60 61 if (*ppos || !*lenp) { 62 *lenp = 0; 63 return 0; 64 } 65 66 /* CPUs are displayed as a hex bitmap + a comma between each groups of 8 67 * nibbles (except the last one which has a newline instead). 68 * Guesstimate the buffer size at the group granularity level. 69 */ 70 len = min(DIV_ROUND_UP(nr_cpumask_bits, 32) * (8 + 1), *lenp); 71 kbuf = kmalloc(len, GFP_KERNEL); 72 if (!kbuf) { 73 *lenp = 0; 74 return -ENOMEM; 75 } 76 77 len = scnprintf(kbuf, len, "%*pb", cpumask_pr_args(mask)); 78 if (!len) { 79 *lenp = 0; 80 goto free_buf; 81 } 82 83 /* scnprintf writes a trailing null char not counted in the returned 84 * length, override it with a newline. 85 */ 86 kbuf[len++] = '\n'; 87 memcpy(buffer, kbuf, len); 88 *lenp = len; 89 *ppos += len; 90 91 free_buf: 92 kfree(kbuf); 93 return 0; 94 } 95 #endif 96 97 #ifdef CONFIG_RPS 98 99 static struct cpumask *rps_default_mask_cow_alloc(struct net *net) 100 { 101 struct cpumask *rps_default_mask; 102 103 if (net->core.rps_default_mask) 104 return net->core.rps_default_mask; 105 106 rps_default_mask = kzalloc(cpumask_size(), GFP_KERNEL); 107 if (!rps_default_mask) 108 return NULL; 109 110 /* pairs with READ_ONCE in rx_queue_default_mask() */ 111 WRITE_ONCE(net->core.rps_default_mask, rps_default_mask); 112 return rps_default_mask; 113 } 114 115 static int rps_default_mask_sysctl(const struct ctl_table *table, int write, 116 void *buffer, size_t *lenp, loff_t *ppos) 117 { 118 struct net *net = (struct net *)table->data; 119 int err = 0; 120 121 rtnl_lock(); 122 if (write) { 123 struct cpumask *rps_default_mask = rps_default_mask_cow_alloc(net); 124 125 err = -ENOMEM; 126 if (!rps_default_mask) 127 goto done; 128 129 err = cpumask_parse(buffer, rps_default_mask); 130 if (err) 131 goto done; 132 133 err = rps_cpumask_housekeeping(rps_default_mask); 134 if (err) 135 goto done; 136 } else { 137 err = dump_cpumask(buffer, lenp, ppos, 138 net->core.rps_default_mask ? : cpu_none_mask); 139 } 140 141 done: 142 rtnl_unlock(); 143 return err; 144 } 145 146 static int rps_sock_flow_sysctl(const struct ctl_table *table, int write, 147 void *buffer, size_t *lenp, loff_t *ppos) 148 { 149 unsigned int orig_size, size; 150 int ret, i; 151 struct ctl_table tmp = { 152 .data = &size, 153 .maxlen = sizeof(size), 154 .mode = table->mode 155 }; 156 struct rps_sock_flow_table *orig_sock_table, *sock_table; 157 static DEFINE_MUTEX(sock_flow_mutex); 158 159 mutex_lock(&sock_flow_mutex); 160 161 orig_sock_table = rcu_dereference_protected( 162 net_hotdata.rps_sock_flow_table, 163 lockdep_is_held(&sock_flow_mutex)); 164 size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0; 165 166 ret = proc_dointvec(&tmp, write, buffer, lenp, ppos); 167 168 if (write) { 169 if (size) { 170 if (size > 1<<29) { 171 /* Enforce limit to prevent overflow */ 172 mutex_unlock(&sock_flow_mutex); 173 return -EINVAL; 174 } 175 size = roundup_pow_of_two(size); 176 if (size != orig_size) { 177 sock_table = 178 vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size)); 179 if (!sock_table) { 180 mutex_unlock(&sock_flow_mutex); 181 return -ENOMEM; 182 } 183 net_hotdata.rps_cpu_mask = 184 roundup_pow_of_two(nr_cpu_ids) - 1; 185 sock_table->mask = size - 1; 186 } else 187 sock_table = orig_sock_table; 188 189 for (i = 0; i < size; i++) 190 sock_table->ents[i] = RPS_NO_CPU; 191 } else 192 sock_table = NULL; 193 194 if (sock_table != orig_sock_table) { 195 rcu_assign_pointer(net_hotdata.rps_sock_flow_table, 196 sock_table); 197 if (sock_table) { 198 static_branch_inc(&rps_needed); 199 static_branch_inc(&rfs_needed); 200 } 201 if (orig_sock_table) { 202 static_branch_dec(&rps_needed); 203 static_branch_dec(&rfs_needed); 204 kvfree_rcu_mightsleep(orig_sock_table); 205 } 206 } 207 } 208 209 mutex_unlock(&sock_flow_mutex); 210 211 return ret; 212 } 213 #endif /* CONFIG_RPS */ 214 215 #ifdef CONFIG_NET_FLOW_LIMIT 216 static DEFINE_MUTEX(flow_limit_update_mutex); 217 218 static int flow_limit_cpu_sysctl(const struct ctl_table *table, int write, 219 void *buffer, size_t *lenp, loff_t *ppos) 220 { 221 struct sd_flow_limit *cur; 222 struct softnet_data *sd; 223 cpumask_var_t mask; 224 int i, len, ret = 0; 225 226 if (!alloc_cpumask_var(&mask, GFP_KERNEL)) 227 return -ENOMEM; 228 229 if (write) { 230 ret = cpumask_parse(buffer, mask); 231 if (ret) 232 goto done; 233 234 mutex_lock(&flow_limit_update_mutex); 235 len = sizeof(*cur) + netdev_flow_limit_table_len; 236 for_each_possible_cpu(i) { 237 sd = &per_cpu(softnet_data, i); 238 cur = rcu_dereference_protected(sd->flow_limit, 239 lockdep_is_held(&flow_limit_update_mutex)); 240 if (cur && !cpumask_test_cpu(i, mask)) { 241 RCU_INIT_POINTER(sd->flow_limit, NULL); 242 kfree_rcu_mightsleep(cur); 243 } else if (!cur && cpumask_test_cpu(i, mask)) { 244 cur = kzalloc_node(len, GFP_KERNEL, 245 cpu_to_node(i)); 246 if (!cur) { 247 /* not unwinding previous changes */ 248 ret = -ENOMEM; 249 goto write_unlock; 250 } 251 cur->num_buckets = netdev_flow_limit_table_len; 252 rcu_assign_pointer(sd->flow_limit, cur); 253 } 254 } 255 write_unlock: 256 mutex_unlock(&flow_limit_update_mutex); 257 } else { 258 cpumask_clear(mask); 259 rcu_read_lock(); 260 for_each_possible_cpu(i) { 261 sd = &per_cpu(softnet_data, i); 262 if (rcu_dereference(sd->flow_limit)) 263 cpumask_set_cpu(i, mask); 264 } 265 rcu_read_unlock(); 266 267 ret = dump_cpumask(buffer, lenp, ppos, mask); 268 } 269 270 done: 271 free_cpumask_var(mask); 272 return ret; 273 } 274 275 static int flow_limit_table_len_sysctl(const struct ctl_table *table, int write, 276 void *buffer, size_t *lenp, loff_t *ppos) 277 { 278 unsigned int old, *ptr; 279 int ret; 280 281 mutex_lock(&flow_limit_update_mutex); 282 283 ptr = table->data; 284 old = *ptr; 285 ret = proc_dointvec(table, write, buffer, lenp, ppos); 286 if (!ret && write && !is_power_of_2(*ptr)) { 287 *ptr = old; 288 ret = -EINVAL; 289 } 290 291 mutex_unlock(&flow_limit_update_mutex); 292 return ret; 293 } 294 #endif /* CONFIG_NET_FLOW_LIMIT */ 295 296 #ifdef CONFIG_NET_SCHED 297 static int set_default_qdisc(const struct ctl_table *table, int write, 298 void *buffer, size_t *lenp, loff_t *ppos) 299 { 300 char id[IFNAMSIZ]; 301 struct ctl_table tbl = { 302 .data = id, 303 .maxlen = IFNAMSIZ, 304 }; 305 int ret; 306 307 qdisc_get_default(id, IFNAMSIZ); 308 309 ret = proc_dostring(&tbl, write, buffer, lenp, ppos); 310 if (write && ret == 0) 311 ret = qdisc_set_default(id); 312 return ret; 313 } 314 #endif 315 316 static int proc_do_dev_weight(const struct ctl_table *table, int write, 317 void *buffer, size_t *lenp, loff_t *ppos) 318 { 319 static DEFINE_MUTEX(dev_weight_mutex); 320 int ret, weight; 321 322 mutex_lock(&dev_weight_mutex); 323 ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); 324 if (!ret && write) { 325 weight = READ_ONCE(weight_p); 326 WRITE_ONCE(net_hotdata.dev_rx_weight, weight * dev_weight_rx_bias); 327 WRITE_ONCE(net_hotdata.dev_tx_weight, weight * dev_weight_tx_bias); 328 } 329 mutex_unlock(&dev_weight_mutex); 330 331 return ret; 332 } 333 334 static int proc_do_rss_key(const struct ctl_table *table, int write, 335 void *buffer, size_t *lenp, loff_t *ppos) 336 { 337 struct ctl_table fake_table; 338 char buf[NETDEV_RSS_KEY_LEN * 3]; 339 340 snprintf(buf, sizeof(buf), "%*phC", NETDEV_RSS_KEY_LEN, netdev_rss_key); 341 fake_table.data = buf; 342 fake_table.maxlen = sizeof(buf); 343 return proc_dostring(&fake_table, write, buffer, lenp, ppos); 344 } 345 346 #ifdef CONFIG_BPF_JIT 347 static int proc_dointvec_minmax_bpf_enable(const struct ctl_table *table, int write, 348 void *buffer, size_t *lenp, 349 loff_t *ppos) 350 { 351 int ret, jit_enable = *(int *)table->data; 352 int min = *(int *)table->extra1; 353 int max = *(int *)table->extra2; 354 struct ctl_table tmp = *table; 355 356 if (write && !capable(CAP_SYS_ADMIN)) 357 return -EPERM; 358 359 tmp.data = &jit_enable; 360 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); 361 if (write && !ret) { 362 if (jit_enable < 2 || 363 (jit_enable == 2 && bpf_dump_raw_ok(current_cred()))) { 364 *(int *)table->data = jit_enable; 365 if (jit_enable == 2) 366 pr_warn("bpf_jit_enable = 2 was set! NEVER use this in production, only for JIT debugging!\n"); 367 } else { 368 ret = -EPERM; 369 } 370 } 371 372 if (write && ret && min == max) 373 pr_info_once("CONFIG_BPF_JIT_ALWAYS_ON is enabled, bpf_jit_enable is permanently set to 1.\n"); 374 375 return ret; 376 } 377 378 # ifdef CONFIG_HAVE_EBPF_JIT 379 static int 380 proc_dointvec_minmax_bpf_restricted(const struct ctl_table *table, int write, 381 void *buffer, size_t *lenp, loff_t *ppos) 382 { 383 if (!capable(CAP_SYS_ADMIN)) 384 return -EPERM; 385 386 return proc_dointvec_minmax(table, write, buffer, lenp, ppos); 387 } 388 # endif /* CONFIG_HAVE_EBPF_JIT */ 389 390 static int 391 proc_dolongvec_minmax_bpf_restricted(const struct ctl_table *table, int write, 392 void *buffer, size_t *lenp, loff_t *ppos) 393 { 394 if (!capable(CAP_SYS_ADMIN)) 395 return -EPERM; 396 397 return proc_doulongvec_minmax(table, write, buffer, lenp, ppos); 398 } 399 #endif 400 401 static struct ctl_table net_core_table[] = { 402 { 403 .procname = "mem_pcpu_rsv", 404 .data = &net_hotdata.sysctl_mem_pcpu_rsv, 405 .maxlen = sizeof(int), 406 .mode = 0644, 407 .proc_handler = proc_dointvec_minmax, 408 .extra1 = &min_mem_pcpu_rsv, 409 }, 410 { 411 .procname = "dev_weight", 412 .data = &weight_p, 413 .maxlen = sizeof(int), 414 .mode = 0644, 415 .proc_handler = proc_do_dev_weight, 416 .extra1 = SYSCTL_ONE, 417 }, 418 { 419 .procname = "dev_weight_rx_bias", 420 .data = &dev_weight_rx_bias, 421 .maxlen = sizeof(int), 422 .mode = 0644, 423 .proc_handler = proc_do_dev_weight, 424 .extra1 = SYSCTL_ONE, 425 }, 426 { 427 .procname = "dev_weight_tx_bias", 428 .data = &dev_weight_tx_bias, 429 .maxlen = sizeof(int), 430 .mode = 0644, 431 .proc_handler = proc_do_dev_weight, 432 .extra1 = SYSCTL_ONE, 433 }, 434 { 435 .procname = "netdev_max_backlog", 436 .data = &net_hotdata.max_backlog, 437 .maxlen = sizeof(int), 438 .mode = 0644, 439 .proc_handler = proc_dointvec 440 }, 441 { 442 .procname = "netdev_rss_key", 443 .data = &netdev_rss_key, 444 .maxlen = sizeof(int), 445 .mode = 0444, 446 .proc_handler = proc_do_rss_key, 447 }, 448 #ifdef CONFIG_BPF_JIT 449 { 450 .procname = "bpf_jit_enable", 451 .data = &bpf_jit_enable, 452 .maxlen = sizeof(int), 453 .mode = 0644, 454 .proc_handler = proc_dointvec_minmax_bpf_enable, 455 # ifdef CONFIG_BPF_JIT_ALWAYS_ON 456 .extra1 = SYSCTL_ONE, 457 .extra2 = SYSCTL_ONE, 458 # else 459 .extra1 = SYSCTL_ZERO, 460 .extra2 = SYSCTL_TWO, 461 # endif 462 }, 463 # ifdef CONFIG_HAVE_EBPF_JIT 464 { 465 .procname = "bpf_jit_harden", 466 .data = &bpf_jit_harden, 467 .maxlen = sizeof(int), 468 .mode = 0600, 469 .proc_handler = proc_dointvec_minmax_bpf_restricted, 470 .extra1 = SYSCTL_ZERO, 471 .extra2 = SYSCTL_TWO, 472 }, 473 { 474 .procname = "bpf_jit_kallsyms", 475 .data = &bpf_jit_kallsyms, 476 .maxlen = sizeof(int), 477 .mode = 0600, 478 .proc_handler = proc_dointvec_minmax_bpf_restricted, 479 .extra1 = SYSCTL_ZERO, 480 .extra2 = SYSCTL_ONE, 481 }, 482 # endif 483 { 484 .procname = "bpf_jit_limit", 485 .data = &bpf_jit_limit, 486 .maxlen = sizeof(long), 487 .mode = 0600, 488 .proc_handler = proc_dolongvec_minmax_bpf_restricted, 489 .extra1 = SYSCTL_LONG_ONE, 490 .extra2 = &bpf_jit_limit_max, 491 }, 492 #endif 493 { 494 .procname = "netdev_tstamp_prequeue", 495 .data = &net_hotdata.tstamp_prequeue, 496 .maxlen = sizeof(int), 497 .mode = 0644, 498 .proc_handler = proc_dointvec 499 }, 500 { 501 .procname = "message_cost", 502 .data = &net_ratelimit_state.interval, 503 .maxlen = sizeof(int), 504 .mode = 0644, 505 .proc_handler = proc_dointvec_jiffies, 506 }, 507 { 508 .procname = "message_burst", 509 .data = &net_ratelimit_state.burst, 510 .maxlen = sizeof(int), 511 .mode = 0644, 512 .proc_handler = proc_dointvec, 513 }, 514 #ifdef CONFIG_RPS 515 { 516 .procname = "rps_sock_flow_entries", 517 .maxlen = sizeof(int), 518 .mode = 0644, 519 .proc_handler = rps_sock_flow_sysctl 520 }, 521 #endif 522 #ifdef CONFIG_NET_FLOW_LIMIT 523 { 524 .procname = "flow_limit_cpu_bitmap", 525 .mode = 0644, 526 .proc_handler = flow_limit_cpu_sysctl 527 }, 528 { 529 .procname = "flow_limit_table_len", 530 .data = &netdev_flow_limit_table_len, 531 .maxlen = sizeof(int), 532 .mode = 0644, 533 .proc_handler = flow_limit_table_len_sysctl 534 }, 535 #endif /* CONFIG_NET_FLOW_LIMIT */ 536 #ifdef CONFIG_NET_RX_BUSY_POLL 537 { 538 .procname = "busy_poll", 539 .data = &sysctl_net_busy_poll, 540 .maxlen = sizeof(unsigned int), 541 .mode = 0644, 542 .proc_handler = proc_dointvec_minmax, 543 .extra1 = SYSCTL_ZERO, 544 }, 545 { 546 .procname = "busy_read", 547 .data = &sysctl_net_busy_read, 548 .maxlen = sizeof(unsigned int), 549 .mode = 0644, 550 .proc_handler = proc_dointvec_minmax, 551 .extra1 = SYSCTL_ZERO, 552 }, 553 #endif 554 #ifdef CONFIG_NET_SCHED 555 { 556 .procname = "default_qdisc", 557 .mode = 0644, 558 .maxlen = IFNAMSIZ, 559 .proc_handler = set_default_qdisc 560 }, 561 #endif 562 { 563 .procname = "netdev_budget", 564 .data = &net_hotdata.netdev_budget, 565 .maxlen = sizeof(int), 566 .mode = 0644, 567 .proc_handler = proc_dointvec 568 }, 569 { 570 .procname = "warnings", 571 .data = &net_msg_warn, 572 .maxlen = sizeof(int), 573 .mode = 0644, 574 .proc_handler = proc_dointvec 575 }, 576 { 577 .procname = "max_skb_frags", 578 .data = &net_hotdata.sysctl_max_skb_frags, 579 .maxlen = sizeof(int), 580 .mode = 0644, 581 .proc_handler = proc_dointvec_minmax, 582 .extra1 = SYSCTL_ONE, 583 .extra2 = &max_skb_frags, 584 }, 585 { 586 .procname = "netdev_budget_usecs", 587 .data = &net_hotdata.netdev_budget_usecs, 588 .maxlen = sizeof(unsigned int), 589 .mode = 0644, 590 .proc_handler = proc_dointvec_minmax, 591 .extra1 = &netdev_budget_usecs_min, 592 }, 593 { 594 .procname = "fb_tunnels_only_for_init_net", 595 .data = &sysctl_fb_tunnels_only_for_init_net, 596 .maxlen = sizeof(int), 597 .mode = 0644, 598 .proc_handler = proc_dointvec_minmax, 599 .extra1 = SYSCTL_ZERO, 600 .extra2 = SYSCTL_TWO, 601 }, 602 { 603 .procname = "devconf_inherit_init_net", 604 .data = &sysctl_devconf_inherit_init_net, 605 .maxlen = sizeof(int), 606 .mode = 0644, 607 .proc_handler = proc_dointvec_minmax, 608 .extra1 = SYSCTL_ZERO, 609 .extra2 = SYSCTL_THREE, 610 }, 611 { 612 .procname = "high_order_alloc_disable", 613 .data = &net_high_order_alloc_disable_key.key, 614 .maxlen = sizeof(net_high_order_alloc_disable_key), 615 .mode = 0644, 616 .proc_handler = proc_do_static_key, 617 }, 618 { 619 .procname = "gro_normal_batch", 620 .data = &net_hotdata.gro_normal_batch, 621 .maxlen = sizeof(unsigned int), 622 .mode = 0644, 623 .proc_handler = proc_dointvec_minmax, 624 .extra1 = SYSCTL_ONE, 625 }, 626 { 627 .procname = "netdev_unregister_timeout_secs", 628 .data = &netdev_unregister_timeout_secs, 629 .maxlen = sizeof(unsigned int), 630 .mode = 0644, 631 .proc_handler = proc_dointvec_minmax, 632 .extra1 = SYSCTL_ONE, 633 .extra2 = &int_3600, 634 }, 635 { 636 .procname = "skb_defer_max", 637 .data = &net_hotdata.sysctl_skb_defer_max, 638 .maxlen = sizeof(unsigned int), 639 .mode = 0644, 640 .proc_handler = proc_dointvec_minmax, 641 .extra1 = SYSCTL_ZERO, 642 }, 643 }; 644 645 static struct ctl_table netns_core_table[] = { 646 #if IS_ENABLED(CONFIG_RPS) 647 { 648 .procname = "rps_default_mask", 649 .data = &init_net, 650 .mode = 0644, 651 .proc_handler = rps_default_mask_sysctl 652 }, 653 #endif 654 { 655 .procname = "somaxconn", 656 .data = &init_net.core.sysctl_somaxconn, 657 .maxlen = sizeof(int), 658 .mode = 0644, 659 .extra1 = SYSCTL_ZERO, 660 .proc_handler = proc_dointvec_minmax 661 }, 662 { 663 .procname = "optmem_max", 664 .data = &init_net.core.sysctl_optmem_max, 665 .maxlen = sizeof(int), 666 .mode = 0644, 667 .extra1 = SYSCTL_ZERO, 668 .proc_handler = proc_dointvec_minmax 669 }, 670 { 671 .procname = "txrehash", 672 .data = &init_net.core.sysctl_txrehash, 673 .maxlen = sizeof(u8), 674 .mode = 0644, 675 .extra1 = SYSCTL_ZERO, 676 .extra2 = SYSCTL_ONE, 677 .proc_handler = proc_dou8vec_minmax, 678 }, 679 { 680 .procname = "tstamp_allow_data", 681 .data = &init_net.core.sysctl_tstamp_allow_data, 682 .maxlen = sizeof(u8), 683 .mode = 0644, 684 .proc_handler = proc_dou8vec_minmax, 685 .extra1 = SYSCTL_ZERO, 686 .extra2 = SYSCTL_ONE 687 }, 688 /* sysctl_core_net_init() will set the values after this 689 * to readonly in network namespaces 690 */ 691 { 692 .procname = "wmem_max", 693 .data = &sysctl_wmem_max, 694 .maxlen = sizeof(int), 695 .mode = 0644, 696 .proc_handler = proc_dointvec_minmax, 697 .extra1 = &min_sndbuf, 698 }, 699 { 700 .procname = "rmem_max", 701 .data = &sysctl_rmem_max, 702 .maxlen = sizeof(int), 703 .mode = 0644, 704 .proc_handler = proc_dointvec_minmax, 705 .extra1 = &min_rcvbuf, 706 }, 707 { 708 .procname = "wmem_default", 709 .data = &sysctl_wmem_default, 710 .maxlen = sizeof(int), 711 .mode = 0644, 712 .proc_handler = proc_dointvec_minmax, 713 .extra1 = &min_sndbuf, 714 }, 715 { 716 .procname = "rmem_default", 717 .data = &sysctl_rmem_default, 718 .maxlen = sizeof(int), 719 .mode = 0644, 720 .proc_handler = proc_dointvec_minmax, 721 .extra1 = &min_rcvbuf, 722 }, 723 }; 724 725 static int __init fb_tunnels_only_for_init_net_sysctl_setup(char *str) 726 { 727 /* fallback tunnels for initns only */ 728 if (!strncmp(str, "initns", 6)) 729 sysctl_fb_tunnels_only_for_init_net = 1; 730 /* no fallback tunnels anywhere */ 731 else if (!strncmp(str, "none", 4)) 732 sysctl_fb_tunnels_only_for_init_net = 2; 733 734 return 1; 735 } 736 __setup("fb_tunnels=", fb_tunnels_only_for_init_net_sysctl_setup); 737 738 static __net_init int sysctl_core_net_init(struct net *net) 739 { 740 size_t table_size = ARRAY_SIZE(netns_core_table); 741 struct ctl_table *tbl; 742 743 tbl = netns_core_table; 744 if (!net_eq(net, &init_net)) { 745 int i; 746 tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL); 747 if (tbl == NULL) 748 goto err_dup; 749 750 for (i = 0; i < table_size; ++i) { 751 if (tbl[i].data == &sysctl_wmem_max) 752 break; 753 754 tbl[i].data += (char *)net - (char *)&init_net; 755 } 756 for (; i < table_size; ++i) 757 tbl[i].mode &= ~0222; 758 } 759 760 net->core.sysctl_hdr = register_net_sysctl_sz(net, "net/core", tbl, table_size); 761 if (net->core.sysctl_hdr == NULL) 762 goto err_reg; 763 764 return 0; 765 766 err_reg: 767 if (tbl != netns_core_table) 768 kfree(tbl); 769 err_dup: 770 return -ENOMEM; 771 } 772 773 static __net_exit void sysctl_core_net_exit(struct net *net) 774 { 775 const struct ctl_table *tbl; 776 777 tbl = net->core.sysctl_hdr->ctl_table_arg; 778 unregister_net_sysctl_table(net->core.sysctl_hdr); 779 BUG_ON(tbl == netns_core_table); 780 #if IS_ENABLED(CONFIG_RPS) 781 kfree(net->core.rps_default_mask); 782 #endif 783 kfree(tbl); 784 } 785 786 static __net_initdata struct pernet_operations sysctl_core_ops = { 787 .init = sysctl_core_net_init, 788 .exit = sysctl_core_net_exit, 789 }; 790 791 static __init int sysctl_core_init(void) 792 { 793 register_net_sysctl(&init_net, "net/core", net_core_table); 794 return register_pernet_subsys(&sysctl_core_ops); 795 } 796 797 fs_initcall(sysctl_core_init); 798