core/sysctl_net_core.c

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