linux/net/core/sysctl_net_core.c
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   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/mm.h>
  10#include <linux/sysctl.h>
  11#include <linux/module.h>
  12#include <linux/socket.h>
  13#include <linux/netdevice.h>
  14#include <linux/ratelimit.h>
  15#include <linux/vmalloc.h>
  16#include <linux/init.h>
  17#include <linux/slab.h>
  18
  19#include <net/ip.h>
  20#include <net/sock.h>
  21#include <net/net_ratelimit.h>
  22#include <net/busy_poll.h>
  23#include <net/pkt_sched.h>
  24
  25static int two = 2;
  26static int three = 3;
  27static int int_3600 = 3600;
  28static int min_sndbuf = SOCK_MIN_SNDBUF;
  29static int min_rcvbuf = SOCK_MIN_RCVBUF;
  30static int max_skb_frags = MAX_SKB_FRAGS;
  31static long long_one __maybe_unused = 1;
  32static long long_max __maybe_unused = LONG_MAX;
  33
  34static int net_msg_warn;        /* Unused, but still a sysctl */
  35
  36int sysctl_fb_tunnels_only_for_init_net __read_mostly = 0;
  37EXPORT_SYMBOL(sysctl_fb_tunnels_only_for_init_net);
  38
  39/* 0 - Keep current behavior:
  40 *     IPv4: inherit all current settings from init_net
  41 *     IPv6: reset all settings to default
  42 * 1 - Both inherit all current settings from init_net
  43 * 2 - Both reset all settings to default
  44 * 3 - Both inherit all settings from current netns
  45 */
  46int sysctl_devconf_inherit_init_net __read_mostly;
  47EXPORT_SYMBOL(sysctl_devconf_inherit_init_net);
  48
  49#ifdef CONFIG_RPS
  50static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
  51                                void *buffer, size_t *lenp, loff_t *ppos)
  52{
  53        unsigned int orig_size, size;
  54        int ret, i;
  55        struct ctl_table tmp = {
  56                .data = &size,
  57                .maxlen = sizeof(size),
  58                .mode = table->mode
  59        };
  60        struct rps_sock_flow_table *orig_sock_table, *sock_table;
  61        static DEFINE_MUTEX(sock_flow_mutex);
  62
  63        mutex_lock(&sock_flow_mutex);
  64
  65        orig_sock_table = rcu_dereference_protected(rps_sock_flow_table,
  66                                        lockdep_is_held(&sock_flow_mutex));
  67        size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;
  68
  69        ret = proc_dointvec(&tmp, write, buffer, lenp, ppos);
  70
  71        if (write) {
  72                if (size) {
  73                        if (size > 1<<29) {
  74                                /* Enforce limit to prevent overflow */
  75                                mutex_unlock(&sock_flow_mutex);
  76                                return -EINVAL;
  77                        }
  78                        size = roundup_pow_of_two(size);
  79                        if (size != orig_size) {
  80                                sock_table =
  81                                    vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size));
  82                                if (!sock_table) {
  83                                        mutex_unlock(&sock_flow_mutex);
  84                                        return -ENOMEM;
  85                                }
  86                                rps_cpu_mask = roundup_pow_of_two(nr_cpu_ids) - 1;
  87                                sock_table->mask = size - 1;
  88                        } else
  89                                sock_table = orig_sock_table;
  90
  91                        for (i = 0; i < size; i++)
  92                                sock_table->ents[i] = RPS_NO_CPU;
  93                } else
  94                        sock_table = NULL;
  95
  96                if (sock_table != orig_sock_table) {
  97                        rcu_assign_pointer(rps_sock_flow_table, sock_table);
  98                        if (sock_table) {
  99                                static_branch_inc(&rps_needed);
 100                                static_branch_inc(&rfs_needed);
 101                        }
 102                        if (orig_sock_table) {
 103                                static_branch_dec(&rps_needed);
 104                                static_branch_dec(&rfs_needed);
 105                                synchronize_rcu();
 106                                vfree(orig_sock_table);
 107                        }
 108                }
 109        }
 110
 111        mutex_unlock(&sock_flow_mutex);
 112
 113        return ret;
 114}
 115#endif /* CONFIG_RPS */
 116
 117#ifdef CONFIG_NET_FLOW_LIMIT
 118static DEFINE_MUTEX(flow_limit_update_mutex);
 119
 120static int flow_limit_cpu_sysctl(struct ctl_table *table, int write,
 121                                 void *buffer, size_t *lenp, loff_t *ppos)
 122{
 123        struct sd_flow_limit *cur;
 124        struct softnet_data *sd;
 125        cpumask_var_t mask;
 126        int i, len, ret = 0;
 127
 128        if (!alloc_cpumask_var(&mask, GFP_KERNEL))
 129                return -ENOMEM;
 130
 131        if (write) {
 132                ret = cpumask_parse(buffer, mask);
 133                if (ret)
 134                        goto done;
 135
 136                mutex_lock(&flow_limit_update_mutex);
 137                len = sizeof(*cur) + netdev_flow_limit_table_len;
 138                for_each_possible_cpu(i) {
 139                        sd = &per_cpu(softnet_data, i);
 140                        cur = rcu_dereference_protected(sd->flow_limit,
 141                                     lockdep_is_held(&flow_limit_update_mutex));
 142                        if (cur && !cpumask_test_cpu(i, mask)) {
 143                                RCU_INIT_POINTER(sd->flow_limit, NULL);
 144                                synchronize_rcu();
 145                                kfree(cur);
 146                        } else if (!cur && cpumask_test_cpu(i, mask)) {
 147                                cur = kzalloc_node(len, GFP_KERNEL,
 148                                                   cpu_to_node(i));
 149                                if (!cur) {
 150                                        /* not unwinding previous changes */
 151                                        ret = -ENOMEM;
 152                                        goto write_unlock;
 153                                }
 154                                cur->num_buckets = netdev_flow_limit_table_len;
 155                                rcu_assign_pointer(sd->flow_limit, cur);
 156                        }
 157                }
 158write_unlock:
 159                mutex_unlock(&flow_limit_update_mutex);
 160        } else {
 161                char kbuf[128];
 162
 163                if (*ppos || !*lenp) {
 164                        *lenp = 0;
 165                        goto done;
 166                }
 167
 168                cpumask_clear(mask);
 169                rcu_read_lock();
 170                for_each_possible_cpu(i) {
 171                        sd = &per_cpu(softnet_data, i);
 172                        if (rcu_dereference(sd->flow_limit))
 173                                cpumask_set_cpu(i, mask);
 174                }
 175                rcu_read_unlock();
 176
 177                len = min(sizeof(kbuf) - 1, *lenp);
 178                len = scnprintf(kbuf, len, "%*pb", cpumask_pr_args(mask));
 179                if (!len) {
 180                        *lenp = 0;
 181                        goto done;
 182                }
 183                if (len < *lenp)
 184                        kbuf[len++] = '\n';
 185                memcpy(buffer, kbuf, len);
 186                *lenp = len;
 187                *ppos += len;
 188        }
 189
 190done:
 191        free_cpumask_var(mask);
 192        return ret;
 193}
 194
 195static int flow_limit_table_len_sysctl(struct ctl_table *table, int write,
 196                                       void *buffer, size_t *lenp, loff_t *ppos)
 197{
 198        unsigned int old, *ptr;
 199        int ret;
 200
 201        mutex_lock(&flow_limit_update_mutex);
 202
 203        ptr = table->data;
 204        old = *ptr;
 205        ret = proc_dointvec(table, write, buffer, lenp, ppos);
 206        if (!ret && write && !is_power_of_2(*ptr)) {
 207                *ptr = old;
 208                ret = -EINVAL;
 209        }
 210
 211        mutex_unlock(&flow_limit_update_mutex);
 212        return ret;
 213}
 214#endif /* CONFIG_NET_FLOW_LIMIT */
 215
 216#ifdef CONFIG_NET_SCHED
 217static int set_default_qdisc(struct ctl_table *table, int write,
 218                             void *buffer, size_t *lenp, loff_t *ppos)
 219{
 220        char id[IFNAMSIZ];
 221        struct ctl_table tbl = {
 222                .data = id,
 223                .maxlen = IFNAMSIZ,
 224        };
 225        int ret;
 226
 227        qdisc_get_default(id, IFNAMSIZ);
 228
 229        ret = proc_dostring(&tbl, write, buffer, lenp, ppos);
 230        if (write && ret == 0)
 231                ret = qdisc_set_default(id);
 232        return ret;
 233}
 234#endif
 235
 236static int proc_do_dev_weight(struct ctl_table *table, int write,
 237                           void *buffer, size_t *lenp, loff_t *ppos)
 238{
 239        int ret;
 240
 241        ret = proc_dointvec(table, write, buffer, lenp, ppos);
 242        if (ret != 0)
 243                return ret;
 244
 245        dev_rx_weight = weight_p * dev_weight_rx_bias;
 246        dev_tx_weight = weight_p * dev_weight_tx_bias;
 247
 248        return ret;
 249}
 250
 251static int proc_do_rss_key(struct ctl_table *table, int write,
 252                           void *buffer, size_t *lenp, loff_t *ppos)
 253{
 254        struct ctl_table fake_table;
 255        char buf[NETDEV_RSS_KEY_LEN * 3];
 256
 257        snprintf(buf, sizeof(buf), "%*phC", NETDEV_RSS_KEY_LEN, netdev_rss_key);
 258        fake_table.data = buf;
 259        fake_table.maxlen = sizeof(buf);
 260        return proc_dostring(&fake_table, write, buffer, lenp, ppos);
 261}
 262
 263#ifdef CONFIG_BPF_JIT
 264static int proc_dointvec_minmax_bpf_enable(struct ctl_table *table, int write,
 265                                           void *buffer, size_t *lenp,
 266                                           loff_t *ppos)
 267{
 268        int ret, jit_enable = *(int *)table->data;
 269        struct ctl_table tmp = *table;
 270
 271        if (write && !capable(CAP_SYS_ADMIN))
 272                return -EPERM;
 273
 274        tmp.data = &jit_enable;
 275        ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
 276        if (write && !ret) {
 277                if (jit_enable < 2 ||
 278                    (jit_enable == 2 && bpf_dump_raw_ok(current_cred()))) {
 279                        *(int *)table->data = jit_enable;
 280                        if (jit_enable == 2)
 281                                pr_warn("bpf_jit_enable = 2 was set! NEVER use this in production, only for JIT debugging!\n");
 282                } else {
 283                        ret = -EPERM;
 284                }
 285        }
 286        return ret;
 287}
 288
 289# ifdef CONFIG_HAVE_EBPF_JIT
 290static int
 291proc_dointvec_minmax_bpf_restricted(struct ctl_table *table, int write,
 292                                    void *buffer, size_t *lenp, loff_t *ppos)
 293{
 294        if (!capable(CAP_SYS_ADMIN))
 295                return -EPERM;
 296
 297        return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
 298}
 299# endif /* CONFIG_HAVE_EBPF_JIT */
 300
 301static int
 302proc_dolongvec_minmax_bpf_restricted(struct ctl_table *table, int write,
 303                                     void *buffer, size_t *lenp, loff_t *ppos)
 304{
 305        if (!capable(CAP_SYS_ADMIN))
 306                return -EPERM;
 307
 308        return proc_doulongvec_minmax(table, write, buffer, lenp, ppos);
 309}
 310#endif
 311
 312static struct ctl_table net_core_table[] = {
 313        {
 314                .procname       = "wmem_max",
 315                .data           = &sysctl_wmem_max,
 316                .maxlen         = sizeof(int),
 317                .mode           = 0644,
 318                .proc_handler   = proc_dointvec_minmax,
 319                .extra1         = &min_sndbuf,
 320        },
 321        {
 322                .procname       = "rmem_max",
 323                .data           = &sysctl_rmem_max,
 324                .maxlen         = sizeof(int),
 325                .mode           = 0644,
 326                .proc_handler   = proc_dointvec_minmax,
 327                .extra1         = &min_rcvbuf,
 328        },
 329        {
 330                .procname       = "wmem_default",
 331                .data           = &sysctl_wmem_default,
 332                .maxlen         = sizeof(int),
 333                .mode           = 0644,
 334                .proc_handler   = proc_dointvec_minmax,
 335                .extra1         = &min_sndbuf,
 336        },
 337        {
 338                .procname       = "rmem_default",
 339                .data           = &sysctl_rmem_default,
 340                .maxlen         = sizeof(int),
 341                .mode           = 0644,
 342                .proc_handler   = proc_dointvec_minmax,
 343                .extra1         = &min_rcvbuf,
 344        },
 345        {
 346                .procname       = "dev_weight",
 347                .data           = &weight_p,
 348                .maxlen         = sizeof(int),
 349                .mode           = 0644,
 350                .proc_handler   = proc_do_dev_weight,
 351        },
 352        {
 353                .procname       = "dev_weight_rx_bias",
 354                .data           = &dev_weight_rx_bias,
 355                .maxlen         = sizeof(int),
 356                .mode           = 0644,
 357                .proc_handler   = proc_do_dev_weight,
 358        },
 359        {
 360                .procname       = "dev_weight_tx_bias",
 361                .data           = &dev_weight_tx_bias,
 362                .maxlen         = sizeof(int),
 363                .mode           = 0644,
 364                .proc_handler   = proc_do_dev_weight,
 365        },
 366        {
 367                .procname       = "netdev_max_backlog",
 368                .data           = &netdev_max_backlog,
 369                .maxlen         = sizeof(int),
 370                .mode           = 0644,
 371                .proc_handler   = proc_dointvec
 372        },
 373        {
 374                .procname       = "netdev_rss_key",
 375                .data           = &netdev_rss_key,
 376                .maxlen         = sizeof(int),
 377                .mode           = 0444,
 378                .proc_handler   = proc_do_rss_key,
 379        },
 380#ifdef CONFIG_BPF_JIT
 381        {
 382                .procname       = "bpf_jit_enable",
 383                .data           = &bpf_jit_enable,
 384                .maxlen         = sizeof(int),
 385                .mode           = 0644,
 386                .proc_handler   = proc_dointvec_minmax_bpf_enable,
 387# ifdef CONFIG_BPF_JIT_ALWAYS_ON
 388                .extra1         = SYSCTL_ONE,
 389                .extra2         = SYSCTL_ONE,
 390# else
 391                .extra1         = SYSCTL_ZERO,
 392                .extra2         = &two,
 393# endif
 394        },
 395# ifdef CONFIG_HAVE_EBPF_JIT
 396        {
 397                .procname       = "bpf_jit_harden",
 398                .data           = &bpf_jit_harden,
 399                .maxlen         = sizeof(int),
 400                .mode           = 0600,
 401                .proc_handler   = proc_dointvec_minmax_bpf_restricted,
 402                .extra1         = SYSCTL_ZERO,
 403                .extra2         = &two,
 404        },
 405        {
 406                .procname       = "bpf_jit_kallsyms",
 407                .data           = &bpf_jit_kallsyms,
 408                .maxlen         = sizeof(int),
 409                .mode           = 0600,
 410                .proc_handler   = proc_dointvec_minmax_bpf_restricted,
 411                .extra1         = SYSCTL_ZERO,
 412                .extra2         = SYSCTL_ONE,
 413        },
 414# endif
 415        {
 416                .procname       = "bpf_jit_limit",
 417                .data           = &bpf_jit_limit,
 418                .maxlen         = sizeof(long),
 419                .mode           = 0600,
 420                .proc_handler   = proc_dolongvec_minmax_bpf_restricted,
 421                .extra1         = &long_one,
 422                .extra2         = &long_max,
 423        },
 424#endif
 425        {
 426                .procname       = "netdev_tstamp_prequeue",
 427                .data           = &netdev_tstamp_prequeue,
 428                .maxlen         = sizeof(int),
 429                .mode           = 0644,
 430                .proc_handler   = proc_dointvec
 431        },
 432        {
 433                .procname       = "message_cost",
 434                .data           = &net_ratelimit_state.interval,
 435                .maxlen         = sizeof(int),
 436                .mode           = 0644,
 437                .proc_handler   = proc_dointvec_jiffies,
 438        },
 439        {
 440                .procname       = "message_burst",
 441                .data           = &net_ratelimit_state.burst,
 442                .maxlen         = sizeof(int),
 443                .mode           = 0644,
 444                .proc_handler   = proc_dointvec,
 445        },
 446        {
 447                .procname       = "optmem_max",
 448                .data           = &sysctl_optmem_max,
 449                .maxlen         = sizeof(int),
 450                .mode           = 0644,
 451                .proc_handler   = proc_dointvec
 452        },
 453        {
 454                .procname       = "tstamp_allow_data",
 455                .data           = &sysctl_tstamp_allow_data,
 456                .maxlen         = sizeof(int),
 457                .mode           = 0644,
 458                .proc_handler   = proc_dointvec_minmax,
 459                .extra1         = SYSCTL_ZERO,
 460                .extra2         = SYSCTL_ONE
 461        },
 462#ifdef CONFIG_RPS
 463        {
 464                .procname       = "rps_sock_flow_entries",
 465                .maxlen         = sizeof(int),
 466                .mode           = 0644,
 467                .proc_handler   = rps_sock_flow_sysctl
 468        },
 469#endif
 470#ifdef CONFIG_NET_FLOW_LIMIT
 471        {
 472                .procname       = "flow_limit_cpu_bitmap",
 473                .mode           = 0644,
 474                .proc_handler   = flow_limit_cpu_sysctl
 475        },
 476        {
 477                .procname       = "flow_limit_table_len",
 478                .data           = &netdev_flow_limit_table_len,
 479                .maxlen         = sizeof(int),
 480                .mode           = 0644,
 481                .proc_handler   = flow_limit_table_len_sysctl
 482        },
 483#endif /* CONFIG_NET_FLOW_LIMIT */
 484#ifdef CONFIG_NET_RX_BUSY_POLL
 485        {
 486                .procname       = "busy_poll",
 487                .data           = &sysctl_net_busy_poll,
 488                .maxlen         = sizeof(unsigned int),
 489                .mode           = 0644,
 490                .proc_handler   = proc_dointvec_minmax,
 491                .extra1         = SYSCTL_ZERO,
 492        },
 493        {
 494                .procname       = "busy_read",
 495                .data           = &sysctl_net_busy_read,
 496                .maxlen         = sizeof(unsigned int),
 497                .mode           = 0644,
 498                .proc_handler   = proc_dointvec_minmax,
 499                .extra1         = SYSCTL_ZERO,
 500        },
 501#endif
 502#ifdef CONFIG_NET_SCHED
 503        {
 504                .procname       = "default_qdisc",
 505                .mode           = 0644,
 506                .maxlen         = IFNAMSIZ,
 507                .proc_handler   = set_default_qdisc
 508        },
 509#endif
 510        {
 511                .procname       = "netdev_budget",
 512                .data           = &netdev_budget,
 513                .maxlen         = sizeof(int),
 514                .mode           = 0644,
 515                .proc_handler   = proc_dointvec
 516        },
 517        {
 518                .procname       = "warnings",
 519                .data           = &net_msg_warn,
 520                .maxlen         = sizeof(int),
 521                .mode           = 0644,
 522                .proc_handler   = proc_dointvec
 523        },
 524        {
 525                .procname       = "max_skb_frags",
 526                .data           = &sysctl_max_skb_frags,
 527                .maxlen         = sizeof(int),
 528                .mode           = 0644,
 529                .proc_handler   = proc_dointvec_minmax,
 530                .extra1         = SYSCTL_ONE,
 531                .extra2         = &max_skb_frags,
 532        },
 533        {
 534                .procname       = "netdev_budget_usecs",
 535                .data           = &netdev_budget_usecs,
 536                .maxlen         = sizeof(unsigned int),
 537                .mode           = 0644,
 538                .proc_handler   = proc_dointvec_minmax,
 539                .extra1         = SYSCTL_ZERO,
 540        },
 541        {
 542                .procname       = "fb_tunnels_only_for_init_net",
 543                .data           = &sysctl_fb_tunnels_only_for_init_net,
 544                .maxlen         = sizeof(int),
 545                .mode           = 0644,
 546                .proc_handler   = proc_dointvec_minmax,
 547                .extra1         = SYSCTL_ZERO,
 548                .extra2         = &two,
 549        },
 550        {
 551                .procname       = "devconf_inherit_init_net",
 552                .data           = &sysctl_devconf_inherit_init_net,
 553                .maxlen         = sizeof(int),
 554                .mode           = 0644,
 555                .proc_handler   = proc_dointvec_minmax,
 556                .extra1         = SYSCTL_ZERO,
 557                .extra2         = &three,
 558        },
 559        {
 560                .procname       = "high_order_alloc_disable",
 561                .data           = &net_high_order_alloc_disable_key.key,
 562                .maxlen         = sizeof(net_high_order_alloc_disable_key),
 563                .mode           = 0644,
 564                .proc_handler   = proc_do_static_key,
 565        },
 566        {
 567                .procname       = "gro_normal_batch",
 568                .data           = &gro_normal_batch,
 569                .maxlen         = sizeof(unsigned int),
 570                .mode           = 0644,
 571                .proc_handler   = proc_dointvec_minmax,
 572                .extra1         = SYSCTL_ONE,
 573        },
 574        {
 575                .procname       = "netdev_unregister_timeout_secs",
 576                .data           = &netdev_unregister_timeout_secs,
 577                .maxlen         = sizeof(unsigned int),
 578                .mode           = 0644,
 579                .proc_handler   = proc_dointvec_minmax,
 580                .extra1         = SYSCTL_ONE,
 581                .extra2         = &int_3600,
 582        },
 583        { }
 584};
 585
 586static struct ctl_table netns_core_table[] = {
 587        {
 588                .procname       = "somaxconn",
 589                .data           = &init_net.core.sysctl_somaxconn,
 590                .maxlen         = sizeof(int),
 591                .mode           = 0644,
 592                .extra1         = SYSCTL_ZERO,
 593                .proc_handler   = proc_dointvec_minmax
 594        },
 595        { }
 596};
 597
 598static int __init fb_tunnels_only_for_init_net_sysctl_setup(char *str)
 599{
 600        /* fallback tunnels for initns only */
 601        if (!strncmp(str, "initns", 6))
 602                sysctl_fb_tunnels_only_for_init_net = 1;
 603        /* no fallback tunnels anywhere */
 604        else if (!strncmp(str, "none", 4))
 605                sysctl_fb_tunnels_only_for_init_net = 2;
 606
 607        return 1;
 608}
 609__setup("fb_tunnels=", fb_tunnels_only_for_init_net_sysctl_setup);
 610
 611static __net_init int sysctl_core_net_init(struct net *net)
 612{
 613        struct ctl_table *tbl;
 614
 615        tbl = netns_core_table;
 616        if (!net_eq(net, &init_net)) {
 617                tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);
 618                if (tbl == NULL)
 619                        goto err_dup;
 620
 621                tbl[0].data = &net->core.sysctl_somaxconn;
 622
 623                /* Don't export any sysctls to unprivileged users */
 624                if (net->user_ns != &init_user_ns) {
 625                        tbl[0].procname = NULL;
 626                }
 627        }
 628
 629        net->core.sysctl_hdr = register_net_sysctl(net, "net/core", tbl);
 630        if (net->core.sysctl_hdr == NULL)
 631                goto err_reg;
 632
 633        return 0;
 634
 635err_reg:
 636        if (tbl != netns_core_table)
 637                kfree(tbl);
 638err_dup:
 639        return -ENOMEM;
 640}
 641
 642static __net_exit void sysctl_core_net_exit(struct net *net)
 643{
 644        struct ctl_table *tbl;
 645
 646        tbl = net->core.sysctl_hdr->ctl_table_arg;
 647        unregister_net_sysctl_table(net->core.sysctl_hdr);
 648        BUG_ON(tbl == netns_core_table);
 649        kfree(tbl);
 650}
 651
 652static __net_initdata struct pernet_operations sysctl_core_ops = {
 653        .init = sysctl_core_net_init,
 654        .exit = sysctl_core_net_exit,
 655};
 656
 657static __init int sysctl_core_init(void)
 658{
 659        register_net_sysctl(&init_net, "net/core", net_core_table);
 660        return register_pernet_subsys(&sysctl_core_ops);
 661}
 662
 663fs_initcall(sysctl_core_init);
 664