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