linux/kernel/sysctl.c
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   1/*
   2 * sysctl.c: General linux system control interface
   3 *
   4 * Begun 24 March 1995, Stephen Tweedie
   5 * Added /proc support, Dec 1995
   6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9 * Dynamic registration fixes, Stephen Tweedie.
  10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12 *  Horn.
  13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16 *  Wendling.
  17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18 *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19 */
  20
  21#include <linux/module.h>
  22#include <linux/mm.h>
  23#include <linux/swap.h>
  24#include <linux/slab.h>
  25#include <linux/sysctl.h>
  26#include <linux/signal.h>
  27#include <linux/printk.h>
  28#include <linux/proc_fs.h>
  29#include <linux/security.h>
  30#include <linux/ctype.h>
  31#include <linux/kmemcheck.h>
  32#include <linux/fs.h>
  33#include <linux/init.h>
  34#include <linux/kernel.h>
  35#include <linux/kobject.h>
  36#include <linux/net.h>
  37#include <linux/sysrq.h>
  38#include <linux/highuid.h>
  39#include <linux/writeback.h>
  40#include <linux/ratelimit.h>
  41#include <linux/compaction.h>
  42#include <linux/hugetlb.h>
  43#include <linux/initrd.h>
  44#include <linux/key.h>
  45#include <linux/times.h>
  46#include <linux/limits.h>
  47#include <linux/dcache.h>
  48#include <linux/dnotify.h>
  49#include <linux/syscalls.h>
  50#include <linux/vmstat.h>
  51#include <linux/nfs_fs.h>
  52#include <linux/acpi.h>
  53#include <linux/reboot.h>
  54#include <linux/ftrace.h>
  55#include <linux/perf_event.h>
  56#include <linux/kprobes.h>
  57#include <linux/pipe_fs_i.h>
  58#include <linux/oom.h>
  59#include <linux/kmod.h>
  60#include <linux/capability.h>
  61
  62#include <asm/uaccess.h>
  63#include <asm/processor.h>
  64
  65#ifdef CONFIG_X86
  66#include <asm/nmi.h>
  67#include <asm/stacktrace.h>
  68#include <asm/io.h>
  69#endif
  70#ifdef CONFIG_BSD_PROCESS_ACCT
  71#include <linux/acct.h>
  72#endif
  73#ifdef CONFIG_RT_MUTEXES
  74#include <linux/rtmutex.h>
  75#endif
  76#if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
  77#include <linux/lockdep.h>
  78#endif
  79#ifdef CONFIG_CHR_DEV_SG
  80#include <scsi/sg.h>
  81#endif
  82
  83#ifdef CONFIG_LOCKUP_DETECTOR
  84#include <linux/nmi.h>
  85#endif
  86
  87
  88#if defined(CONFIG_SYSCTL)
  89
  90/* External variables not in a header file. */
  91extern int sysctl_overcommit_memory;
  92extern int sysctl_overcommit_ratio;
  93extern int max_threads;
  94extern int core_uses_pid;
  95extern int suid_dumpable;
  96extern char core_pattern[];
  97extern unsigned int core_pipe_limit;
  98extern int pid_max;
  99extern int min_free_kbytes;
 100extern int pid_max_min, pid_max_max;
 101extern int sysctl_drop_caches;
 102extern int percpu_pagelist_fraction;
 103extern int compat_log;
 104extern int latencytop_enabled;
 105extern int sysctl_nr_open_min, sysctl_nr_open_max;
 106#ifndef CONFIG_MMU
 107extern int sysctl_nr_trim_pages;
 108#endif
 109#ifdef CONFIG_BLOCK
 110extern int blk_iopoll_enabled;
 111#endif
 112
 113/* Constants used for minimum and  maximum */
 114#ifdef CONFIG_LOCKUP_DETECTOR
 115static int sixty = 60;
 116static int neg_one = -1;
 117#endif
 118
 119static int zero;
 120static int __maybe_unused one = 1;
 121static int __maybe_unused two = 2;
 122static int __maybe_unused three = 3;
 123static unsigned long one_ul = 1;
 124static int one_hundred = 100;
 125#ifdef CONFIG_PRINTK
 126static int ten_thousand = 10000;
 127#endif
 128
 129/* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
 130static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
 131
 132/* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 133static int maxolduid = 65535;
 134static int minolduid;
 135static int min_percpu_pagelist_fract = 8;
 136
 137static int ngroups_max = NGROUPS_MAX;
 138static const int cap_last_cap = CAP_LAST_CAP;
 139
 140#ifdef CONFIG_INOTIFY_USER
 141#include <linux/inotify.h>
 142#endif
 143#ifdef CONFIG_SPARC
 144#include <asm/system.h>
 145#endif
 146
 147#ifdef CONFIG_SPARC64
 148extern int sysctl_tsb_ratio;
 149#endif
 150
 151#ifdef __hppa__
 152extern int pwrsw_enabled;
 153extern int unaligned_enabled;
 154#endif
 155
 156#ifdef CONFIG_IA64
 157extern int no_unaligned_warning;
 158extern int unaligned_dump_stack;
 159#endif
 160
 161#ifdef CONFIG_PROC_SYSCTL
 162static int proc_do_cad_pid(struct ctl_table *table, int write,
 163                  void __user *buffer, size_t *lenp, loff_t *ppos);
 164static int proc_taint(struct ctl_table *table, int write,
 165                               void __user *buffer, size_t *lenp, loff_t *ppos);
 166#endif
 167
 168#ifdef CONFIG_PRINTK
 169static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
 170                                void __user *buffer, size_t *lenp, loff_t *ppos);
 171#endif
 172
 173#ifdef CONFIG_MAGIC_SYSRQ
 174/* Note: sysrq code uses it's own private copy */
 175static int __sysrq_enabled = SYSRQ_DEFAULT_ENABLE;
 176
 177static int sysrq_sysctl_handler(ctl_table *table, int write,
 178                                void __user *buffer, size_t *lenp,
 179                                loff_t *ppos)
 180{
 181        int error;
 182
 183        error = proc_dointvec(table, write, buffer, lenp, ppos);
 184        if (error)
 185                return error;
 186
 187        if (write)
 188                sysrq_toggle_support(__sysrq_enabled);
 189
 190        return 0;
 191}
 192
 193#endif
 194
 195static struct ctl_table root_table[];
 196static struct ctl_table_root sysctl_table_root;
 197static struct ctl_table_header root_table_header = {
 198        {{.count = 1,
 199        .ctl_table = root_table,
 200        .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),}},
 201        .root = &sysctl_table_root,
 202        .set = &sysctl_table_root.default_set,
 203};
 204static struct ctl_table_root sysctl_table_root = {
 205        .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
 206        .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
 207};
 208
 209static struct ctl_table kern_table[];
 210static struct ctl_table vm_table[];
 211static struct ctl_table fs_table[];
 212static struct ctl_table debug_table[];
 213static struct ctl_table dev_table[];
 214extern struct ctl_table random_table[];
 215#ifdef CONFIG_EPOLL
 216extern struct ctl_table epoll_table[];
 217#endif
 218
 219#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 220int sysctl_legacy_va_layout;
 221#endif
 222
 223/* The default sysctl tables: */
 224
 225static struct ctl_table root_table[] = {
 226        {
 227                .procname       = "kernel",
 228                .mode           = 0555,
 229                .child          = kern_table,
 230        },
 231        {
 232                .procname       = "vm",
 233                .mode           = 0555,
 234                .child          = vm_table,
 235        },
 236        {
 237                .procname       = "fs",
 238                .mode           = 0555,
 239                .child          = fs_table,
 240        },
 241        {
 242                .procname       = "debug",
 243                .mode           = 0555,
 244                .child          = debug_table,
 245        },
 246        {
 247                .procname       = "dev",
 248                .mode           = 0555,
 249                .child          = dev_table,
 250        },
 251        { }
 252};
 253
 254#ifdef CONFIG_SCHED_DEBUG
 255static int min_sched_granularity_ns = 100000;           /* 100 usecs */
 256static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
 257static int min_wakeup_granularity_ns;                   /* 0 usecs */
 258static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
 259static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
 260static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
 261#endif
 262
 263#ifdef CONFIG_COMPACTION
 264static int min_extfrag_threshold;
 265static int max_extfrag_threshold = 1000;
 266#endif
 267
 268static struct ctl_table kern_table[] = {
 269        {
 270                .procname       = "sched_child_runs_first",
 271                .data           = &sysctl_sched_child_runs_first,
 272                .maxlen         = sizeof(unsigned int),
 273                .mode           = 0644,
 274                .proc_handler   = proc_dointvec,
 275        },
 276#ifdef CONFIG_SCHED_DEBUG
 277        {
 278                .procname       = "sched_min_granularity_ns",
 279                .data           = &sysctl_sched_min_granularity,
 280                .maxlen         = sizeof(unsigned int),
 281                .mode           = 0644,
 282                .proc_handler   = sched_proc_update_handler,
 283                .extra1         = &min_sched_granularity_ns,
 284                .extra2         = &max_sched_granularity_ns,
 285        },
 286        {
 287                .procname       = "sched_latency_ns",
 288                .data           = &sysctl_sched_latency,
 289                .maxlen         = sizeof(unsigned int),
 290                .mode           = 0644,
 291                .proc_handler   = sched_proc_update_handler,
 292                .extra1         = &min_sched_granularity_ns,
 293                .extra2         = &max_sched_granularity_ns,
 294        },
 295        {
 296                .procname       = "sched_wakeup_granularity_ns",
 297                .data           = &sysctl_sched_wakeup_granularity,
 298                .maxlen         = sizeof(unsigned int),
 299                .mode           = 0644,
 300                .proc_handler   = sched_proc_update_handler,
 301                .extra1         = &min_wakeup_granularity_ns,
 302                .extra2         = &max_wakeup_granularity_ns,
 303        },
 304        {
 305                .procname       = "sched_tunable_scaling",
 306                .data           = &sysctl_sched_tunable_scaling,
 307                .maxlen         = sizeof(enum sched_tunable_scaling),
 308                .mode           = 0644,
 309                .proc_handler   = sched_proc_update_handler,
 310                .extra1         = &min_sched_tunable_scaling,
 311                .extra2         = &max_sched_tunable_scaling,
 312        },
 313        {
 314                .procname       = "sched_migration_cost",
 315                .data           = &sysctl_sched_migration_cost,
 316                .maxlen         = sizeof(unsigned int),
 317                .mode           = 0644,
 318                .proc_handler   = proc_dointvec,
 319        },
 320        {
 321                .procname       = "sched_nr_migrate",
 322                .data           = &sysctl_sched_nr_migrate,
 323                .maxlen         = sizeof(unsigned int),
 324                .mode           = 0644,
 325                .proc_handler   = proc_dointvec,
 326        },
 327        {
 328                .procname       = "sched_time_avg",
 329                .data           = &sysctl_sched_time_avg,
 330                .maxlen         = sizeof(unsigned int),
 331                .mode           = 0644,
 332                .proc_handler   = proc_dointvec,
 333        },
 334        {
 335                .procname       = "sched_shares_window",
 336                .data           = &sysctl_sched_shares_window,
 337                .maxlen         = sizeof(unsigned int),
 338                .mode           = 0644,
 339                .proc_handler   = proc_dointvec,
 340        },
 341        {
 342                .procname       = "timer_migration",
 343                .data           = &sysctl_timer_migration,
 344                .maxlen         = sizeof(unsigned int),
 345                .mode           = 0644,
 346                .proc_handler   = proc_dointvec_minmax,
 347                .extra1         = &zero,
 348                .extra2         = &one,
 349        },
 350#endif
 351        {
 352                .procname       = "sched_rt_period_us",
 353                .data           = &sysctl_sched_rt_period,
 354                .maxlen         = sizeof(unsigned int),
 355                .mode           = 0644,
 356                .proc_handler   = sched_rt_handler,
 357        },
 358        {
 359                .procname       = "sched_rt_runtime_us",
 360                .data           = &sysctl_sched_rt_runtime,
 361                .maxlen         = sizeof(int),
 362                .mode           = 0644,
 363                .proc_handler   = sched_rt_handler,
 364        },
 365#ifdef CONFIG_SCHED_AUTOGROUP
 366        {
 367                .procname       = "sched_autogroup_enabled",
 368                .data           = &sysctl_sched_autogroup_enabled,
 369                .maxlen         = sizeof(unsigned int),
 370                .mode           = 0644,
 371                .proc_handler   = proc_dointvec_minmax,
 372                .extra1         = &zero,
 373                .extra2         = &one,
 374        },
 375#endif
 376#ifdef CONFIG_CFS_BANDWIDTH
 377        {
 378                .procname       = "sched_cfs_bandwidth_slice_us",
 379                .data           = &sysctl_sched_cfs_bandwidth_slice,
 380                .maxlen         = sizeof(unsigned int),
 381                .mode           = 0644,
 382                .proc_handler   = proc_dointvec_minmax,
 383                .extra1         = &one,
 384        },
 385#endif
 386#ifdef CONFIG_PROVE_LOCKING
 387        {
 388                .procname       = "prove_locking",
 389                .data           = &prove_locking,
 390                .maxlen         = sizeof(int),
 391                .mode           = 0644,
 392                .proc_handler   = proc_dointvec,
 393        },
 394#endif
 395#ifdef CONFIG_LOCK_STAT
 396        {
 397                .procname       = "lock_stat",
 398                .data           = &lock_stat,
 399                .maxlen         = sizeof(int),
 400                .mode           = 0644,
 401                .proc_handler   = proc_dointvec,
 402        },
 403#endif
 404        {
 405                .procname       = "panic",
 406                .data           = &panic_timeout,
 407                .maxlen         = sizeof(int),
 408                .mode           = 0644,
 409                .proc_handler   = proc_dointvec,
 410        },
 411        {
 412                .procname       = "core_uses_pid",
 413                .data           = &core_uses_pid,
 414                .maxlen         = sizeof(int),
 415                .mode           = 0644,
 416                .proc_handler   = proc_dointvec,
 417        },
 418        {
 419                .procname       = "core_pattern",
 420                .data           = core_pattern,
 421                .maxlen         = CORENAME_MAX_SIZE,
 422                .mode           = 0644,
 423                .proc_handler   = proc_dostring,
 424        },
 425        {
 426                .procname       = "core_pipe_limit",
 427                .data           = &core_pipe_limit,
 428                .maxlen         = sizeof(unsigned int),
 429                .mode           = 0644,
 430                .proc_handler   = proc_dointvec,
 431        },
 432#ifdef CONFIG_PROC_SYSCTL
 433        {
 434                .procname       = "tainted",
 435                .maxlen         = sizeof(long),
 436                .mode           = 0644,
 437                .proc_handler   = proc_taint,
 438        },
 439#endif
 440#ifdef CONFIG_LATENCYTOP
 441        {
 442                .procname       = "latencytop",
 443                .data           = &latencytop_enabled,
 444                .maxlen         = sizeof(int),
 445                .mode           = 0644,
 446                .proc_handler   = proc_dointvec,
 447        },
 448#endif
 449#ifdef CONFIG_BLK_DEV_INITRD
 450        {
 451                .procname       = "real-root-dev",
 452                .data           = &real_root_dev,
 453                .maxlen         = sizeof(int),
 454                .mode           = 0644,
 455                .proc_handler   = proc_dointvec,
 456        },
 457#endif
 458        {
 459                .procname       = "print-fatal-signals",
 460                .data           = &print_fatal_signals,
 461                .maxlen         = sizeof(int),
 462                .mode           = 0644,
 463                .proc_handler   = proc_dointvec,
 464        },
 465#ifdef CONFIG_SPARC
 466        {
 467                .procname       = "reboot-cmd",
 468                .data           = reboot_command,
 469                .maxlen         = 256,
 470                .mode           = 0644,
 471                .proc_handler   = proc_dostring,
 472        },
 473        {
 474                .procname       = "stop-a",
 475                .data           = &stop_a_enabled,
 476                .maxlen         = sizeof (int),
 477                .mode           = 0644,
 478                .proc_handler   = proc_dointvec,
 479        },
 480        {
 481                .procname       = "scons-poweroff",
 482                .data           = &scons_pwroff,
 483                .maxlen         = sizeof (int),
 484                .mode           = 0644,
 485                .proc_handler   = proc_dointvec,
 486        },
 487#endif
 488#ifdef CONFIG_SPARC64
 489        {
 490                .procname       = "tsb-ratio",
 491                .data           = &sysctl_tsb_ratio,
 492                .maxlen         = sizeof (int),
 493                .mode           = 0644,
 494                .proc_handler   = proc_dointvec,
 495        },
 496#endif
 497#ifdef __hppa__
 498        {
 499                .procname       = "soft-power",
 500                .data           = &pwrsw_enabled,
 501                .maxlen         = sizeof (int),
 502                .mode           = 0644,
 503                .proc_handler   = proc_dointvec,
 504        },
 505        {
 506                .procname       = "unaligned-trap",
 507                .data           = &unaligned_enabled,
 508                .maxlen         = sizeof (int),
 509                .mode           = 0644,
 510                .proc_handler   = proc_dointvec,
 511        },
 512#endif
 513        {
 514                .procname       = "ctrl-alt-del",
 515                .data           = &C_A_D,
 516                .maxlen         = sizeof(int),
 517                .mode           = 0644,
 518                .proc_handler   = proc_dointvec,
 519        },
 520#ifdef CONFIG_FUNCTION_TRACER
 521        {
 522                .procname       = "ftrace_enabled",
 523                .data           = &ftrace_enabled,
 524                .maxlen         = sizeof(int),
 525                .mode           = 0644,
 526                .proc_handler   = ftrace_enable_sysctl,
 527        },
 528#endif
 529#ifdef CONFIG_STACK_TRACER
 530        {
 531                .procname       = "stack_tracer_enabled",
 532                .data           = &stack_tracer_enabled,
 533                .maxlen         = sizeof(int),
 534                .mode           = 0644,
 535                .proc_handler   = stack_trace_sysctl,
 536        },
 537#endif
 538#ifdef CONFIG_TRACING
 539        {
 540                .procname       = "ftrace_dump_on_oops",
 541                .data           = &ftrace_dump_on_oops,
 542                .maxlen         = sizeof(int),
 543                .mode           = 0644,
 544                .proc_handler   = proc_dointvec,
 545        },
 546#endif
 547#ifdef CONFIG_MODULES
 548        {
 549                .procname       = "modprobe",
 550                .data           = &modprobe_path,
 551                .maxlen         = KMOD_PATH_LEN,
 552                .mode           = 0644,
 553                .proc_handler   = proc_dostring,
 554        },
 555        {
 556                .procname       = "modules_disabled",
 557                .data           = &modules_disabled,
 558                .maxlen         = sizeof(int),
 559                .mode           = 0644,
 560                /* only handle a transition from default "0" to "1" */
 561                .proc_handler   = proc_dointvec_minmax,
 562                .extra1         = &one,
 563                .extra2         = &one,
 564        },
 565#endif
 566#ifdef CONFIG_HOTPLUG
 567        {
 568                .procname       = "hotplug",
 569                .data           = &uevent_helper,
 570                .maxlen         = UEVENT_HELPER_PATH_LEN,
 571                .mode           = 0644,
 572                .proc_handler   = proc_dostring,
 573        },
 574#endif
 575#ifdef CONFIG_CHR_DEV_SG
 576        {
 577                .procname       = "sg-big-buff",
 578                .data           = &sg_big_buff,
 579                .maxlen         = sizeof (int),
 580                .mode           = 0444,
 581                .proc_handler   = proc_dointvec,
 582        },
 583#endif
 584#ifdef CONFIG_BSD_PROCESS_ACCT
 585        {
 586                .procname       = "acct",
 587                .data           = &acct_parm,
 588                .maxlen         = 3*sizeof(int),
 589                .mode           = 0644,
 590                .proc_handler   = proc_dointvec,
 591        },
 592#endif
 593#ifdef CONFIG_MAGIC_SYSRQ
 594        {
 595                .procname       = "sysrq",
 596                .data           = &__sysrq_enabled,
 597                .maxlen         = sizeof (int),
 598                .mode           = 0644,
 599                .proc_handler   = sysrq_sysctl_handler,
 600        },
 601#endif
 602#ifdef CONFIG_PROC_SYSCTL
 603        {
 604                .procname       = "cad_pid",
 605                .data           = NULL,
 606                .maxlen         = sizeof (int),
 607                .mode           = 0600,
 608                .proc_handler   = proc_do_cad_pid,
 609        },
 610#endif
 611        {
 612                .procname       = "threads-max",
 613                .data           = &max_threads,
 614                .maxlen         = sizeof(int),
 615                .mode           = 0644,
 616                .proc_handler   = proc_dointvec,
 617        },
 618        {
 619                .procname       = "random",
 620                .mode           = 0555,
 621                .child          = random_table,
 622        },
 623        {
 624                .procname       = "usermodehelper",
 625                .mode           = 0555,
 626                .child          = usermodehelper_table,
 627        },
 628        {
 629                .procname       = "overflowuid",
 630                .data           = &overflowuid,
 631                .maxlen         = sizeof(int),
 632                .mode           = 0644,
 633                .proc_handler   = proc_dointvec_minmax,
 634                .extra1         = &minolduid,
 635                .extra2         = &maxolduid,
 636        },
 637        {
 638                .procname       = "overflowgid",
 639                .data           = &overflowgid,
 640                .maxlen         = sizeof(int),
 641                .mode           = 0644,
 642                .proc_handler   = proc_dointvec_minmax,
 643                .extra1         = &minolduid,
 644                .extra2         = &maxolduid,
 645        },
 646#ifdef CONFIG_S390
 647#ifdef CONFIG_MATHEMU
 648        {
 649                .procname       = "ieee_emulation_warnings",
 650                .data           = &sysctl_ieee_emulation_warnings,
 651                .maxlen         = sizeof(int),
 652                .mode           = 0644,
 653                .proc_handler   = proc_dointvec,
 654        },
 655#endif
 656        {
 657                .procname       = "userprocess_debug",
 658                .data           = &show_unhandled_signals,
 659                .maxlen         = sizeof(int),
 660                .mode           = 0644,
 661                .proc_handler   = proc_dointvec,
 662        },
 663#endif
 664        {
 665                .procname       = "pid_max",
 666                .data           = &pid_max,
 667                .maxlen         = sizeof (int),
 668                .mode           = 0644,
 669                .proc_handler   = proc_dointvec_minmax,
 670                .extra1         = &pid_max_min,
 671                .extra2         = &pid_max_max,
 672        },
 673        {
 674                .procname       = "panic_on_oops",
 675                .data           = &panic_on_oops,
 676                .maxlen         = sizeof(int),
 677                .mode           = 0644,
 678                .proc_handler   = proc_dointvec,
 679        },
 680#if defined CONFIG_PRINTK
 681        {
 682                .procname       = "printk",
 683                .data           = &console_loglevel,
 684                .maxlen         = 4*sizeof(int),
 685                .mode           = 0644,
 686                .proc_handler   = proc_dointvec,
 687        },
 688        {
 689                .procname       = "printk_ratelimit",
 690                .data           = &printk_ratelimit_state.interval,
 691                .maxlen         = sizeof(int),
 692                .mode           = 0644,
 693                .proc_handler   = proc_dointvec_jiffies,
 694        },
 695        {
 696                .procname       = "printk_ratelimit_burst",
 697                .data           = &printk_ratelimit_state.burst,
 698                .maxlen         = sizeof(int),
 699                .mode           = 0644,
 700                .proc_handler   = proc_dointvec,
 701        },
 702        {
 703                .procname       = "printk_delay",
 704                .data           = &printk_delay_msec,
 705                .maxlen         = sizeof(int),
 706                .mode           = 0644,
 707                .proc_handler   = proc_dointvec_minmax,
 708                .extra1         = &zero,
 709                .extra2         = &ten_thousand,
 710        },
 711        {
 712                .procname       = "dmesg_restrict",
 713                .data           = &dmesg_restrict,
 714                .maxlen         = sizeof(int),
 715                .mode           = 0644,
 716                .proc_handler   = proc_dointvec_minmax_sysadmin,
 717                .extra1         = &zero,
 718                .extra2         = &one,
 719        },
 720        {
 721                .procname       = "kptr_restrict",
 722                .data           = &kptr_restrict,
 723                .maxlen         = sizeof(int),
 724                .mode           = 0644,
 725                .proc_handler   = proc_dointvec_minmax_sysadmin,
 726                .extra1         = &zero,
 727                .extra2         = &two,
 728        },
 729#endif
 730        {
 731                .procname       = "ngroups_max",
 732                .data           = &ngroups_max,
 733                .maxlen         = sizeof (int),
 734                .mode           = 0444,
 735                .proc_handler   = proc_dointvec,
 736        },
 737        {
 738                .procname       = "cap_last_cap",
 739                .data           = (void *)&cap_last_cap,
 740                .maxlen         = sizeof(int),
 741                .mode           = 0444,
 742                .proc_handler   = proc_dointvec,
 743        },
 744#if defined(CONFIG_LOCKUP_DETECTOR)
 745        {
 746                .procname       = "watchdog",
 747                .data           = &watchdog_enabled,
 748                .maxlen         = sizeof (int),
 749                .mode           = 0644,
 750                .proc_handler   = proc_dowatchdog,
 751                .extra1         = &zero,
 752                .extra2         = &one,
 753        },
 754        {
 755                .procname       = "watchdog_thresh",
 756                .data           = &watchdog_thresh,
 757                .maxlen         = sizeof(int),
 758                .mode           = 0644,
 759                .proc_handler   = proc_dowatchdog,
 760                .extra1         = &neg_one,
 761                .extra2         = &sixty,
 762        },
 763        {
 764                .procname       = "softlockup_panic",
 765                .data           = &softlockup_panic,
 766                .maxlen         = sizeof(int),
 767                .mode           = 0644,
 768                .proc_handler   = proc_dointvec_minmax,
 769                .extra1         = &zero,
 770                .extra2         = &one,
 771        },
 772        {
 773                .procname       = "nmi_watchdog",
 774                .data           = &watchdog_enabled,
 775                .maxlen         = sizeof (int),
 776                .mode           = 0644,
 777                .proc_handler   = proc_dowatchdog,
 778                .extra1         = &zero,
 779                .extra2         = &one,
 780        },
 781#endif
 782#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 783        {
 784                .procname       = "unknown_nmi_panic",
 785                .data           = &unknown_nmi_panic,
 786                .maxlen         = sizeof (int),
 787                .mode           = 0644,
 788                .proc_handler   = proc_dointvec,
 789        },
 790#endif
 791#if defined(CONFIG_X86)
 792        {
 793                .procname       = "panic_on_unrecovered_nmi",
 794                .data           = &panic_on_unrecovered_nmi,
 795                .maxlen         = sizeof(int),
 796                .mode           = 0644,
 797                .proc_handler   = proc_dointvec,
 798        },
 799        {
 800                .procname       = "panic_on_io_nmi",
 801                .data           = &panic_on_io_nmi,
 802                .maxlen         = sizeof(int),
 803                .mode           = 0644,
 804                .proc_handler   = proc_dointvec,
 805        },
 806#ifdef CONFIG_DEBUG_STACKOVERFLOW
 807        {
 808                .procname       = "panic_on_stackoverflow",
 809                .data           = &sysctl_panic_on_stackoverflow,
 810                .maxlen         = sizeof(int),
 811                .mode           = 0644,
 812                .proc_handler   = proc_dointvec,
 813        },
 814#endif
 815        {
 816                .procname       = "bootloader_type",
 817                .data           = &bootloader_type,
 818                .maxlen         = sizeof (int),
 819                .mode           = 0444,
 820                .proc_handler   = proc_dointvec,
 821        },
 822        {
 823                .procname       = "bootloader_version",
 824                .data           = &bootloader_version,
 825                .maxlen         = sizeof (int),
 826                .mode           = 0444,
 827                .proc_handler   = proc_dointvec,
 828        },
 829        {
 830                .procname       = "kstack_depth_to_print",
 831                .data           = &kstack_depth_to_print,
 832                .maxlen         = sizeof(int),
 833                .mode           = 0644,
 834                .proc_handler   = proc_dointvec,
 835        },
 836        {
 837                .procname       = "io_delay_type",
 838                .data           = &io_delay_type,
 839                .maxlen         = sizeof(int),
 840                .mode           = 0644,
 841                .proc_handler   = proc_dointvec,
 842        },
 843#endif
 844#if defined(CONFIG_MMU)
 845        {
 846                .procname       = "randomize_va_space",
 847                .data           = &randomize_va_space,
 848                .maxlen         = sizeof(int),
 849                .mode           = 0644,
 850                .proc_handler   = proc_dointvec,
 851        },
 852#endif
 853#if defined(CONFIG_S390) && defined(CONFIG_SMP)
 854        {
 855                .procname       = "spin_retry",
 856                .data           = &spin_retry,
 857                .maxlen         = sizeof (int),
 858                .mode           = 0644,
 859                .proc_handler   = proc_dointvec,
 860        },
 861#endif
 862#if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 863        {
 864                .procname       = "acpi_video_flags",
 865                .data           = &acpi_realmode_flags,
 866                .maxlen         = sizeof (unsigned long),
 867                .mode           = 0644,
 868                .proc_handler   = proc_doulongvec_minmax,
 869        },
 870#endif
 871#ifdef CONFIG_IA64
 872        {
 873                .procname       = "ignore-unaligned-usertrap",
 874                .data           = &no_unaligned_warning,
 875                .maxlen         = sizeof (int),
 876                .mode           = 0644,
 877                .proc_handler   = proc_dointvec,
 878        },
 879        {
 880                .procname       = "unaligned-dump-stack",
 881                .data           = &unaligned_dump_stack,
 882                .maxlen         = sizeof (int),
 883                .mode           = 0644,
 884                .proc_handler   = proc_dointvec,
 885        },
 886#endif
 887#ifdef CONFIG_DETECT_HUNG_TASK
 888        {
 889                .procname       = "hung_task_panic",
 890                .data           = &sysctl_hung_task_panic,
 891                .maxlen         = sizeof(int),
 892                .mode           = 0644,
 893                .proc_handler   = proc_dointvec_minmax,
 894                .extra1         = &zero,
 895                .extra2         = &one,
 896        },
 897        {
 898                .procname       = "hung_task_check_count",
 899                .data           = &sysctl_hung_task_check_count,
 900                .maxlen         = sizeof(unsigned long),
 901                .mode           = 0644,
 902                .proc_handler   = proc_doulongvec_minmax,
 903        },
 904        {
 905                .procname       = "hung_task_timeout_secs",
 906                .data           = &sysctl_hung_task_timeout_secs,
 907                .maxlen         = sizeof(unsigned long),
 908                .mode           = 0644,
 909                .proc_handler   = proc_dohung_task_timeout_secs,
 910        },
 911        {
 912                .procname       = "hung_task_warnings",
 913                .data           = &sysctl_hung_task_warnings,
 914                .maxlen         = sizeof(unsigned long),
 915                .mode           = 0644,
 916                .proc_handler   = proc_doulongvec_minmax,
 917        },
 918#endif
 919#ifdef CONFIG_COMPAT
 920        {
 921                .procname       = "compat-log",
 922                .data           = &compat_log,
 923                .maxlen         = sizeof (int),
 924                .mode           = 0644,
 925                .proc_handler   = proc_dointvec,
 926        },
 927#endif
 928#ifdef CONFIG_RT_MUTEXES
 929        {
 930                .procname       = "max_lock_depth",
 931                .data           = &max_lock_depth,
 932                .maxlen         = sizeof(int),
 933                .mode           = 0644,
 934                .proc_handler   = proc_dointvec,
 935        },
 936#endif
 937        {
 938                .procname       = "poweroff_cmd",
 939                .data           = &poweroff_cmd,
 940                .maxlen         = POWEROFF_CMD_PATH_LEN,
 941                .mode           = 0644,
 942                .proc_handler   = proc_dostring,
 943        },
 944#ifdef CONFIG_KEYS
 945        {
 946                .procname       = "keys",
 947                .mode           = 0555,
 948                .child          = key_sysctls,
 949        },
 950#endif
 951#ifdef CONFIG_RCU_TORTURE_TEST
 952        {
 953                .procname       = "rcutorture_runnable",
 954                .data           = &rcutorture_runnable,
 955                .maxlen         = sizeof(int),
 956                .mode           = 0644,
 957                .proc_handler   = proc_dointvec,
 958        },
 959#endif
 960#ifdef CONFIG_PERF_EVENTS
 961        /*
 962         * User-space scripts rely on the existence of this file
 963         * as a feature check for perf_events being enabled.
 964         *
 965         * So it's an ABI, do not remove!
 966         */
 967        {
 968                .procname       = "perf_event_paranoid",
 969                .data           = &sysctl_perf_event_paranoid,
 970                .maxlen         = sizeof(sysctl_perf_event_paranoid),
 971                .mode           = 0644,
 972                .proc_handler   = proc_dointvec,
 973        },
 974        {
 975                .procname       = "perf_event_mlock_kb",
 976                .data           = &sysctl_perf_event_mlock,
 977                .maxlen         = sizeof(sysctl_perf_event_mlock),
 978                .mode           = 0644,
 979                .proc_handler   = proc_dointvec,
 980        },
 981        {
 982                .procname       = "perf_event_max_sample_rate",
 983                .data           = &sysctl_perf_event_sample_rate,
 984                .maxlen         = sizeof(sysctl_perf_event_sample_rate),
 985                .mode           = 0644,
 986                .proc_handler   = perf_proc_update_handler,
 987        },
 988#endif
 989#ifdef CONFIG_KMEMCHECK
 990        {
 991                .procname       = "kmemcheck",
 992                .data           = &kmemcheck_enabled,
 993                .maxlen         = sizeof(int),
 994                .mode           = 0644,
 995                .proc_handler   = proc_dointvec,
 996        },
 997#endif
 998#ifdef CONFIG_BLOCK
 999        {
1000                .procname       = "blk_iopoll",
1001                .data           = &blk_iopoll_enabled,
1002                .maxlen         = sizeof(int),
1003                .mode           = 0644,
1004                .proc_handler   = proc_dointvec,
1005        },
1006#endif
1007        { }
1008};
1009
1010static struct ctl_table vm_table[] = {
1011        {
1012                .procname       = "overcommit_memory",
1013                .data           = &sysctl_overcommit_memory,
1014                .maxlen         = sizeof(sysctl_overcommit_memory),
1015                .mode           = 0644,
1016                .proc_handler   = proc_dointvec_minmax,
1017                .extra1         = &zero,
1018                .extra2         = &two,
1019        },
1020        {
1021                .procname       = "panic_on_oom",
1022                .data           = &sysctl_panic_on_oom,
1023                .maxlen         = sizeof(sysctl_panic_on_oom),
1024                .mode           = 0644,
1025                .proc_handler   = proc_dointvec_minmax,
1026                .extra1         = &zero,
1027                .extra2         = &two,
1028        },
1029        {
1030                .procname       = "oom_kill_allocating_task",
1031                .data           = &sysctl_oom_kill_allocating_task,
1032                .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
1033                .mode           = 0644,
1034                .proc_handler   = proc_dointvec,
1035        },
1036        {
1037                .procname       = "oom_dump_tasks",
1038                .data           = &sysctl_oom_dump_tasks,
1039                .maxlen         = sizeof(sysctl_oom_dump_tasks),
1040                .mode           = 0644,
1041                .proc_handler   = proc_dointvec,
1042        },
1043        {
1044                .procname       = "overcommit_ratio",
1045                .data           = &sysctl_overcommit_ratio,
1046                .maxlen         = sizeof(sysctl_overcommit_ratio),
1047                .mode           = 0644,
1048                .proc_handler   = proc_dointvec,
1049        },
1050        {
1051                .procname       = "page-cluster", 
1052                .data           = &page_cluster,
1053                .maxlen         = sizeof(int),
1054                .mode           = 0644,
1055                .proc_handler   = proc_dointvec_minmax,
1056                .extra1         = &zero,
1057        },
1058        {
1059                .procname       = "dirty_background_ratio",
1060                .data           = &dirty_background_ratio,
1061                .maxlen         = sizeof(dirty_background_ratio),
1062                .mode           = 0644,
1063                .proc_handler   = dirty_background_ratio_handler,
1064                .extra1         = &zero,
1065                .extra2         = &one_hundred,
1066        },
1067        {
1068                .procname       = "dirty_background_bytes",
1069                .data           = &dirty_background_bytes,
1070                .maxlen         = sizeof(dirty_background_bytes),
1071                .mode           = 0644,
1072                .proc_handler   = dirty_background_bytes_handler,
1073                .extra1         = &one_ul,
1074        },
1075        {
1076                .procname       = "dirty_ratio",
1077                .data           = &vm_dirty_ratio,
1078                .maxlen         = sizeof(vm_dirty_ratio),
1079                .mode           = 0644,
1080                .proc_handler   = dirty_ratio_handler,
1081                .extra1         = &zero,
1082                .extra2         = &one_hundred,
1083        },
1084        {
1085                .procname       = "dirty_bytes",
1086                .data           = &vm_dirty_bytes,
1087                .maxlen         = sizeof(vm_dirty_bytes),
1088                .mode           = 0644,
1089                .proc_handler   = dirty_bytes_handler,
1090                .extra1         = &dirty_bytes_min,
1091        },
1092        {
1093                .procname       = "dirty_writeback_centisecs",
1094                .data           = &dirty_writeback_interval,
1095                .maxlen         = sizeof(dirty_writeback_interval),
1096                .mode           = 0644,
1097                .proc_handler   = dirty_writeback_centisecs_handler,
1098        },
1099        {
1100                .procname       = "dirty_expire_centisecs",
1101                .data           = &dirty_expire_interval,
1102                .maxlen         = sizeof(dirty_expire_interval),
1103                .mode           = 0644,
1104                .proc_handler   = proc_dointvec_minmax,
1105                .extra1         = &zero,
1106        },
1107        {
1108                .procname       = "nr_pdflush_threads",
1109                .data           = &nr_pdflush_threads,
1110                .maxlen         = sizeof nr_pdflush_threads,
1111                .mode           = 0444 /* read-only*/,
1112                .proc_handler   = proc_dointvec,
1113        },
1114        {
1115                .procname       = "swappiness",
1116                .data           = &vm_swappiness,
1117                .maxlen         = sizeof(vm_swappiness),
1118                .mode           = 0644,
1119                .proc_handler   = proc_dointvec_minmax,
1120                .extra1         = &zero,
1121                .extra2         = &one_hundred,
1122        },
1123#ifdef CONFIG_HUGETLB_PAGE
1124        {
1125                .procname       = "nr_hugepages",
1126                .data           = NULL,
1127                .maxlen         = sizeof(unsigned long),
1128                .mode           = 0644,
1129                .proc_handler   = hugetlb_sysctl_handler,
1130                .extra1         = (void *)&hugetlb_zero,
1131                .extra2         = (void *)&hugetlb_infinity,
1132        },
1133#ifdef CONFIG_NUMA
1134        {
1135                .procname       = "nr_hugepages_mempolicy",
1136                .data           = NULL,
1137                .maxlen         = sizeof(unsigned long),
1138                .mode           = 0644,
1139                .proc_handler   = &hugetlb_mempolicy_sysctl_handler,
1140                .extra1         = (void *)&hugetlb_zero,
1141                .extra2         = (void *)&hugetlb_infinity,
1142        },
1143#endif
1144         {
1145                .procname       = "hugetlb_shm_group",
1146                .data           = &sysctl_hugetlb_shm_group,
1147                .maxlen         = sizeof(gid_t),
1148                .mode           = 0644,
1149                .proc_handler   = proc_dointvec,
1150         },
1151         {
1152                .procname       = "hugepages_treat_as_movable",
1153                .data           = &hugepages_treat_as_movable,
1154                .maxlen         = sizeof(int),
1155                .mode           = 0644,
1156                .proc_handler   = hugetlb_treat_movable_handler,
1157        },
1158        {
1159                .procname       = "nr_overcommit_hugepages",
1160                .data           = NULL,
1161                .maxlen         = sizeof(unsigned long),
1162                .mode           = 0644,
1163                .proc_handler   = hugetlb_overcommit_handler,
1164                .extra1         = (void *)&hugetlb_zero,
1165                .extra2         = (void *)&hugetlb_infinity,
1166        },
1167#endif
1168        {
1169                .procname       = "lowmem_reserve_ratio",
1170                .data           = &sysctl_lowmem_reserve_ratio,
1171                .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1172                .mode           = 0644,
1173                .proc_handler   = lowmem_reserve_ratio_sysctl_handler,
1174        },
1175        {
1176                .procname       = "drop_caches",
1177                .data           = &sysctl_drop_caches,
1178                .maxlen         = sizeof(int),
1179                .mode           = 0644,
1180                .proc_handler   = drop_caches_sysctl_handler,
1181                .extra1         = &one,
1182                .extra2         = &three,
1183        },
1184#ifdef CONFIG_COMPACTION
1185        {
1186                .procname       = "compact_memory",
1187                .data           = &sysctl_compact_memory,
1188                .maxlen         = sizeof(int),
1189                .mode           = 0200,
1190                .proc_handler   = sysctl_compaction_handler,
1191        },
1192        {
1193                .procname       = "extfrag_threshold",
1194                .data           = &sysctl_extfrag_threshold,
1195                .maxlen         = sizeof(int),
1196                .mode           = 0644,
1197                .proc_handler   = sysctl_extfrag_handler,
1198                .extra1         = &min_extfrag_threshold,
1199                .extra2         = &max_extfrag_threshold,
1200        },
1201
1202#endif /* CONFIG_COMPACTION */
1203        {
1204                .procname       = "min_free_kbytes",
1205                .data           = &min_free_kbytes,
1206                .maxlen         = sizeof(min_free_kbytes),
1207                .mode           = 0644,
1208                .proc_handler   = min_free_kbytes_sysctl_handler,
1209                .extra1         = &zero,
1210        },
1211        {
1212                .procname       = "percpu_pagelist_fraction",
1213                .data           = &percpu_pagelist_fraction,
1214                .maxlen         = sizeof(percpu_pagelist_fraction),
1215                .mode           = 0644,
1216                .proc_handler   = percpu_pagelist_fraction_sysctl_handler,
1217                .extra1         = &min_percpu_pagelist_fract,
1218        },
1219#ifdef CONFIG_MMU
1220        {
1221                .procname       = "max_map_count",
1222                .data           = &sysctl_max_map_count,
1223                .maxlen         = sizeof(sysctl_max_map_count),
1224                .mode           = 0644,
1225                .proc_handler   = proc_dointvec_minmax,
1226                .extra1         = &zero,
1227        },
1228#else
1229        {
1230                .procname       = "nr_trim_pages",
1231                .data           = &sysctl_nr_trim_pages,
1232                .maxlen         = sizeof(sysctl_nr_trim_pages),
1233                .mode           = 0644,
1234                .proc_handler   = proc_dointvec_minmax,
1235                .extra1         = &zero,
1236        },
1237#endif
1238        {
1239                .procname       = "laptop_mode",
1240                .data           = &laptop_mode,
1241                .maxlen         = sizeof(laptop_mode),
1242                .mode           = 0644,
1243                .proc_handler   = proc_dointvec_jiffies,
1244        },
1245        {
1246                .procname       = "block_dump",
1247                .data           = &block_dump,
1248                .maxlen         = sizeof(block_dump),
1249                .mode           = 0644,
1250                .proc_handler   = proc_dointvec,
1251                .extra1         = &zero,
1252        },
1253        {
1254                .procname       = "vfs_cache_pressure",
1255                .data           = &sysctl_vfs_cache_pressure,
1256                .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1257                .mode           = 0644,
1258                .proc_handler   = proc_dointvec,
1259                .extra1         = &zero,
1260        },
1261#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1262        {
1263                .procname       = "legacy_va_layout",
1264                .data           = &sysctl_legacy_va_layout,
1265                .maxlen         = sizeof(sysctl_legacy_va_layout),
1266                .mode           = 0644,
1267                .proc_handler   = proc_dointvec,
1268                .extra1         = &zero,
1269        },
1270#endif
1271#ifdef CONFIG_NUMA
1272        {
1273                .procname       = "zone_reclaim_mode",
1274                .data           = &zone_reclaim_mode,
1275                .maxlen         = sizeof(zone_reclaim_mode),
1276                .mode           = 0644,
1277                .proc_handler   = proc_dointvec,
1278                .extra1         = &zero,
1279        },
1280        {
1281                .procname       = "min_unmapped_ratio",
1282                .data           = &sysctl_min_unmapped_ratio,
1283                .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1284                .mode           = 0644,
1285                .proc_handler   = sysctl_min_unmapped_ratio_sysctl_handler,
1286                .extra1         = &zero,
1287                .extra2         = &one_hundred,
1288        },
1289        {
1290                .procname       = "min_slab_ratio",
1291                .data           = &sysctl_min_slab_ratio,
1292                .maxlen         = sizeof(sysctl_min_slab_ratio),
1293                .mode           = 0644,
1294                .proc_handler   = sysctl_min_slab_ratio_sysctl_handler,
1295                .extra1         = &zero,
1296                .extra2         = &one_hundred,
1297        },
1298#endif
1299#ifdef CONFIG_SMP
1300        {
1301                .procname       = "stat_interval",
1302                .data           = &sysctl_stat_interval,
1303                .maxlen         = sizeof(sysctl_stat_interval),
1304                .mode           = 0644,
1305                .proc_handler   = proc_dointvec_jiffies,
1306        },
1307#endif
1308#ifdef CONFIG_MMU
1309        {
1310                .procname       = "mmap_min_addr",
1311                .data           = &dac_mmap_min_addr,
1312                .maxlen         = sizeof(unsigned long),
1313                .mode           = 0644,
1314                .proc_handler   = mmap_min_addr_handler,
1315        },
1316#endif
1317#ifdef CONFIG_NUMA
1318        {
1319                .procname       = "numa_zonelist_order",
1320                .data           = &numa_zonelist_order,
1321                .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1322                .mode           = 0644,
1323                .proc_handler   = numa_zonelist_order_handler,
1324        },
1325#endif
1326#if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1327   (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1328        {
1329                .procname       = "vdso_enabled",
1330                .data           = &vdso_enabled,
1331                .maxlen         = sizeof(vdso_enabled),
1332                .mode           = 0644,
1333                .proc_handler   = proc_dointvec,
1334                .extra1         = &zero,
1335        },
1336#endif
1337#ifdef CONFIG_HIGHMEM
1338        {
1339                .procname       = "highmem_is_dirtyable",
1340                .data           = &vm_highmem_is_dirtyable,
1341                .maxlen         = sizeof(vm_highmem_is_dirtyable),
1342                .mode           = 0644,
1343                .proc_handler   = proc_dointvec_minmax,
1344                .extra1         = &zero,
1345                .extra2         = &one,
1346        },
1347#endif
1348        {
1349                .procname       = "scan_unevictable_pages",
1350                .data           = &scan_unevictable_pages,
1351                .maxlen         = sizeof(scan_unevictable_pages),
1352                .mode           = 0644,
1353                .proc_handler   = scan_unevictable_handler,
1354        },
1355#ifdef CONFIG_MEMORY_FAILURE
1356        {
1357                .procname       = "memory_failure_early_kill",
1358                .data           = &sysctl_memory_failure_early_kill,
1359                .maxlen         = sizeof(sysctl_memory_failure_early_kill),
1360                .mode           = 0644,
1361                .proc_handler   = proc_dointvec_minmax,
1362                .extra1         = &zero,
1363                .extra2         = &one,
1364        },
1365        {
1366                .procname       = "memory_failure_recovery",
1367                .data           = &sysctl_memory_failure_recovery,
1368                .maxlen         = sizeof(sysctl_memory_failure_recovery),
1369                .mode           = 0644,
1370                .proc_handler   = proc_dointvec_minmax,
1371                .extra1         = &zero,
1372                .extra2         = &one,
1373        },
1374#endif
1375        { }
1376};
1377
1378#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1379static struct ctl_table binfmt_misc_table[] = {
1380        { }
1381};
1382#endif
1383
1384static struct ctl_table fs_table[] = {
1385        {
1386                .procname       = "inode-nr",
1387                .data           = &inodes_stat,
1388                .maxlen         = 2*sizeof(int),
1389                .mode           = 0444,
1390                .proc_handler   = proc_nr_inodes,
1391        },
1392        {
1393                .procname       = "inode-state",
1394                .data           = &inodes_stat,
1395                .maxlen         = 7*sizeof(int),
1396                .mode           = 0444,
1397                .proc_handler   = proc_nr_inodes,
1398        },
1399        {
1400                .procname       = "file-nr",
1401                .data           = &files_stat,
1402                .maxlen         = sizeof(files_stat),
1403                .mode           = 0444,
1404                .proc_handler   = proc_nr_files,
1405        },
1406        {
1407                .procname       = "file-max",
1408                .data           = &files_stat.max_files,
1409                .maxlen         = sizeof(files_stat.max_files),
1410                .mode           = 0644,
1411                .proc_handler   = proc_doulongvec_minmax,
1412        },
1413        {
1414                .procname       = "nr_open",
1415                .data           = &sysctl_nr_open,
1416                .maxlen         = sizeof(int),
1417                .mode           = 0644,
1418                .proc_handler   = proc_dointvec_minmax,
1419                .extra1         = &sysctl_nr_open_min,
1420                .extra2         = &sysctl_nr_open_max,
1421        },
1422        {
1423                .procname       = "dentry-state",
1424                .data           = &dentry_stat,
1425                .maxlen         = 6*sizeof(int),
1426                .mode           = 0444,
1427                .proc_handler   = proc_nr_dentry,
1428        },
1429        {
1430                .procname       = "overflowuid",
1431                .data           = &fs_overflowuid,
1432                .maxlen         = sizeof(int),
1433                .mode           = 0644,
1434                .proc_handler   = proc_dointvec_minmax,
1435                .extra1         = &minolduid,
1436                .extra2         = &maxolduid,
1437        },
1438        {
1439                .procname       = "overflowgid",
1440                .data           = &fs_overflowgid,
1441                .maxlen         = sizeof(int),
1442                .mode           = 0644,
1443                .proc_handler   = proc_dointvec_minmax,
1444                .extra1         = &minolduid,
1445                .extra2         = &maxolduid,
1446        },
1447#ifdef CONFIG_FILE_LOCKING
1448        {
1449                .procname       = "leases-enable",
1450                .data           = &leases_enable,
1451                .maxlen         = sizeof(int),
1452                .mode           = 0644,
1453                .proc_handler   = proc_dointvec,
1454        },
1455#endif
1456#ifdef CONFIG_DNOTIFY
1457        {
1458                .procname       = "dir-notify-enable",
1459                .data           = &dir_notify_enable,
1460                .maxlen         = sizeof(int),
1461                .mode           = 0644,
1462                .proc_handler   = proc_dointvec,
1463        },
1464#endif
1465#ifdef CONFIG_MMU
1466#ifdef CONFIG_FILE_LOCKING
1467        {
1468                .procname       = "lease-break-time",
1469                .data           = &lease_break_time,
1470                .maxlen         = sizeof(int),
1471                .mode           = 0644,
1472                .proc_handler   = proc_dointvec,
1473        },
1474#endif
1475#ifdef CONFIG_AIO
1476        {
1477                .procname       = "aio-nr",
1478                .data           = &aio_nr,
1479                .maxlen         = sizeof(aio_nr),
1480                .mode           = 0444,
1481                .proc_handler   = proc_doulongvec_minmax,
1482        },
1483        {
1484                .procname       = "aio-max-nr",
1485                .data           = &aio_max_nr,
1486                .maxlen         = sizeof(aio_max_nr),
1487                .mode           = 0644,
1488                .proc_handler   = proc_doulongvec_minmax,
1489        },
1490#endif /* CONFIG_AIO */
1491#ifdef CONFIG_INOTIFY_USER
1492        {
1493                .procname       = "inotify",
1494                .mode           = 0555,
1495                .child          = inotify_table,
1496        },
1497#endif  
1498#ifdef CONFIG_EPOLL
1499        {
1500                .procname       = "epoll",
1501                .mode           = 0555,
1502                .child          = epoll_table,
1503        },
1504#endif
1505#endif
1506        {
1507                .procname       = "suid_dumpable",
1508                .data           = &suid_dumpable,
1509                .maxlen         = sizeof(int),
1510                .mode           = 0644,
1511                .proc_handler   = proc_dointvec_minmax,
1512                .extra1         = &zero,
1513                .extra2         = &two,
1514        },
1515#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1516        {
1517                .procname       = "binfmt_misc",
1518                .mode           = 0555,
1519                .child          = binfmt_misc_table,
1520        },
1521#endif
1522        {
1523                .procname       = "pipe-max-size",
1524                .data           = &pipe_max_size,
1525                .maxlen         = sizeof(int),
1526                .mode           = 0644,
1527                .proc_handler   = &pipe_proc_fn,
1528                .extra1         = &pipe_min_size,
1529        },
1530        { }
1531};
1532
1533static struct ctl_table debug_table[] = {
1534#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
1535    defined(CONFIG_S390) || defined(CONFIG_TILE)
1536        {
1537                .procname       = "exception-trace",
1538                .data           = &show_unhandled_signals,
1539                .maxlen         = sizeof(int),
1540                .mode           = 0644,
1541                .proc_handler   = proc_dointvec
1542        },
1543#endif
1544#if defined(CONFIG_OPTPROBES)
1545        {
1546                .procname       = "kprobes-optimization",
1547                .data           = &sysctl_kprobes_optimization,
1548                .maxlen         = sizeof(int),
1549                .mode           = 0644,
1550                .proc_handler   = proc_kprobes_optimization_handler,
1551                .extra1         = &zero,
1552                .extra2         = &one,
1553        },
1554#endif
1555        { }
1556};
1557
1558static struct ctl_table dev_table[] = {
1559        { }
1560};
1561
1562static DEFINE_SPINLOCK(sysctl_lock);
1563
1564/* called under sysctl_lock */
1565static int use_table(struct ctl_table_header *p)
1566{
1567        if (unlikely(p->unregistering))
1568                return 0;
1569        p->used++;
1570        return 1;
1571}
1572
1573/* called under sysctl_lock */
1574static void unuse_table(struct ctl_table_header *p)
1575{
1576        if (!--p->used)
1577                if (unlikely(p->unregistering))
1578                        complete(p->unregistering);
1579}
1580
1581/* called under sysctl_lock, will reacquire if has to wait */
1582static void start_unregistering(struct ctl_table_header *p)
1583{
1584        /*
1585         * if p->used is 0, nobody will ever touch that entry again;
1586         * we'll eliminate all paths to it before dropping sysctl_lock
1587         */
1588        if (unlikely(p->used)) {
1589                struct completion wait;
1590                init_completion(&wait);
1591                p->unregistering = &wait;
1592                spin_unlock(&sysctl_lock);
1593                wait_for_completion(&wait);
1594                spin_lock(&sysctl_lock);
1595        } else {
1596                /* anything non-NULL; we'll never dereference it */
1597                p->unregistering = ERR_PTR(-EINVAL);
1598        }
1599        /*
1600         * do not remove from the list until nobody holds it; walking the
1601         * list in do_sysctl() relies on that.
1602         */
1603        list_del_init(&p->ctl_entry);
1604}
1605
1606void sysctl_head_get(struct ctl_table_header *head)
1607{
1608        spin_lock(&sysctl_lock);
1609        head->count++;
1610        spin_unlock(&sysctl_lock);
1611}
1612
1613void sysctl_head_put(struct ctl_table_header *head)
1614{
1615        spin_lock(&sysctl_lock);
1616        if (!--head->count)
1617                kfree_rcu(head, rcu);
1618        spin_unlock(&sysctl_lock);
1619}
1620
1621struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1622{
1623        if (!head)
1624                BUG();
1625        spin_lock(&sysctl_lock);
1626        if (!use_table(head))
1627                head = ERR_PTR(-ENOENT);
1628        spin_unlock(&sysctl_lock);
1629        return head;
1630}
1631
1632void sysctl_head_finish(struct ctl_table_header *head)
1633{
1634        if (!head)
1635                return;
1636        spin_lock(&sysctl_lock);
1637        unuse_table(head);
1638        spin_unlock(&sysctl_lock);
1639}
1640
1641static struct ctl_table_set *
1642lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1643{
1644        struct ctl_table_set *set = &root->default_set;
1645        if (root->lookup)
1646                set = root->lookup(root, namespaces);
1647        return set;
1648}
1649
1650static struct list_head *
1651lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1652{
1653        struct ctl_table_set *set = lookup_header_set(root, namespaces);
1654        return &set->list;
1655}
1656
1657struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1658                                            struct ctl_table_header *prev)
1659{
1660        struct ctl_table_root *root;
1661        struct list_head *header_list;
1662        struct ctl_table_header *head;
1663        struct list_head *tmp;
1664
1665        spin_lock(&sysctl_lock);
1666        if (prev) {
1667                head = prev;
1668                tmp = &prev->ctl_entry;
1669                unuse_table(prev);
1670                goto next;
1671        }
1672        tmp = &root_table_header.ctl_entry;
1673        for (;;) {
1674                head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1675
1676                if (!use_table(head))
1677                        goto next;
1678                spin_unlock(&sysctl_lock);
1679                return head;
1680        next:
1681                root = head->root;
1682                tmp = tmp->next;
1683                header_list = lookup_header_list(root, namespaces);
1684                if (tmp != header_list)
1685                        continue;
1686
1687                do {
1688                        root = list_entry(root->root_list.next,
1689                                        struct ctl_table_root, root_list);
1690                        if (root == &sysctl_table_root)
1691                                goto out;
1692                        header_list = lookup_header_list(root, namespaces);
1693                } while (list_empty(header_list));
1694                tmp = header_list->next;
1695        }
1696out:
1697        spin_unlock(&sysctl_lock);
1698        return NULL;
1699}
1700
1701struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1702{
1703        return __sysctl_head_next(current->nsproxy, prev);
1704}
1705
1706void register_sysctl_root(struct ctl_table_root *root)
1707{
1708        spin_lock(&sysctl_lock);
1709        list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1710        spin_unlock(&sysctl_lock);
1711}
1712
1713/*
1714 * sysctl_perm does NOT grant the superuser all rights automatically, because
1715 * some sysctl variables are readonly even to root.
1716 */
1717
1718static int test_perm(int mode, int op)
1719{
1720        if (!current_euid())
1721                mode >>= 6;
1722        else if (in_egroup_p(0))
1723                mode >>= 3;
1724        if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1725                return 0;
1726        return -EACCES;
1727}
1728
1729int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1730{
1731        int mode;
1732
1733        if (root->permissions)
1734                mode = root->permissions(root, current->nsproxy, table);
1735        else
1736                mode = table->mode;
1737
1738        return test_perm(mode, op);
1739}
1740
1741static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1742{
1743        for (; table->procname; table++) {
1744                table->parent = parent;
1745                if (table->child)
1746                        sysctl_set_parent(table, table->child);
1747        }
1748}
1749
1750static __init int sysctl_init(void)
1751{
1752        sysctl_set_parent(NULL, root_table);
1753#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1754        sysctl_check_table(current->nsproxy, root_table);
1755#endif
1756        return 0;
1757}
1758
1759core_initcall(sysctl_init);
1760
1761static struct ctl_table *is_branch_in(struct ctl_table *branch,
1762                                      struct ctl_table *table)
1763{
1764        struct ctl_table *p;
1765        const char *s = branch->procname;
1766
1767        /* branch should have named subdirectory as its first element */
1768        if (!s || !branch->child)
1769                return NULL;
1770
1771        /* ... and nothing else */
1772        if (branch[1].procname)
1773                return NULL;
1774
1775        /* table should contain subdirectory with the same name */
1776        for (p = table; p->procname; p++) {
1777                if (!p->child)
1778                        continue;
1779                if (p->procname && strcmp(p->procname, s) == 0)
1780                        return p;
1781        }
1782        return NULL;
1783}
1784
1785/* see if attaching q to p would be an improvement */
1786static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1787{
1788        struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1789        struct ctl_table *next;
1790        int is_better = 0;
1791        int not_in_parent = !p->attached_by;
1792
1793        while ((next = is_branch_in(by, to)) != NULL) {
1794                if (by == q->attached_by)
1795                        is_better = 1;
1796                if (to == p->attached_by)
1797                        not_in_parent = 1;
1798                by = by->child;
1799                to = next->child;
1800        }
1801
1802        if (is_better && not_in_parent) {
1803                q->attached_by = by;
1804                q->attached_to = to;
1805                q->parent = p;
1806        }
1807}
1808
1809/**
1810 * __register_sysctl_paths - register a sysctl hierarchy
1811 * @root: List of sysctl headers to register on
1812 * @namespaces: Data to compute which lists of sysctl entries are visible
1813 * @path: The path to the directory the sysctl table is in.
1814 * @table: the top-level table structure
1815 *
1816 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1817 * array. A completely 0 filled entry terminates the table.
1818 *
1819 * The members of the &struct ctl_table structure are used as follows:
1820 *
1821 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1822 *            enter a sysctl file
1823 *
1824 * data - a pointer to data for use by proc_handler
1825 *
1826 * maxlen - the maximum size in bytes of the data
1827 *
1828 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1829 *
1830 * child - a pointer to the child sysctl table if this entry is a directory, or
1831 *         %NULL.
1832 *
1833 * proc_handler - the text handler routine (described below)
1834 *
1835 * de - for internal use by the sysctl routines
1836 *
1837 * extra1, extra2 - extra pointers usable by the proc handler routines
1838 *
1839 * Leaf nodes in the sysctl tree will be represented by a single file
1840 * under /proc; non-leaf nodes will be represented by directories.
1841 *
1842 * sysctl(2) can automatically manage read and write requests through
1843 * the sysctl table.  The data and maxlen fields of the ctl_table
1844 * struct enable minimal validation of the values being written to be
1845 * performed, and the mode field allows minimal authentication.
1846 *
1847 * There must be a proc_handler routine for any terminal nodes
1848 * mirrored under /proc/sys (non-terminals are handled by a built-in
1849 * directory handler).  Several default handlers are available to
1850 * cover common cases -
1851 *
1852 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1853 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 
1854 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1855 *
1856 * It is the handler's job to read the input buffer from user memory
1857 * and process it. The handler should return 0 on success.
1858 *
1859 * This routine returns %NULL on a failure to register, and a pointer
1860 * to the table header on success.
1861 */
1862struct ctl_table_header *__register_sysctl_paths(
1863        struct ctl_table_root *root,
1864        struct nsproxy *namespaces,
1865        const struct ctl_path *path, struct ctl_table *table)
1866{
1867        struct ctl_table_header *header;
1868        struct ctl_table *new, **prevp;
1869        unsigned int n, npath;
1870        struct ctl_table_set *set;
1871
1872        /* Count the path components */
1873        for (npath = 0; path[npath].procname; ++npath)
1874                ;
1875
1876        /*
1877         * For each path component, allocate a 2-element ctl_table array.
1878         * The first array element will be filled with the sysctl entry
1879         * for this, the second will be the sentinel (procname == 0).
1880         *
1881         * We allocate everything in one go so that we don't have to
1882         * worry about freeing additional memory in unregister_sysctl_table.
1883         */
1884        header = kzalloc(sizeof(struct ctl_table_header) +
1885                         (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1886        if (!header)
1887                return NULL;
1888
1889        new = (struct ctl_table *) (header + 1);
1890
1891        /* Now connect the dots */
1892        prevp = &header->ctl_table;
1893        for (n = 0; n < npath; ++n, ++path) {
1894                /* Copy the procname */
1895                new->procname = path->procname;
1896                new->mode     = 0555;
1897
1898                *prevp = new;
1899                prevp = &new->child;
1900
1901                new += 2;
1902        }
1903        *prevp = table;
1904        header->ctl_table_arg = table;
1905
1906        INIT_LIST_HEAD(&header->ctl_entry);
1907        header->used = 0;
1908        header->unregistering = NULL;
1909        header->root = root;
1910        sysctl_set_parent(NULL, header->ctl_table);
1911        header->count = 1;
1912#ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1913        if (sysctl_check_table(namespaces, header->ctl_table)) {
1914                kfree(header);
1915                return NULL;
1916        }
1917#endif
1918        spin_lock(&sysctl_lock);
1919        header->set = lookup_header_set(root, namespaces);
1920        header->attached_by = header->ctl_table;
1921        header->attached_to = root_table;
1922        header->parent = &root_table_header;
1923        for (set = header->set; set; set = set->parent) {
1924                struct ctl_table_header *p;
1925                list_for_each_entry(p, &set->list, ctl_entry) {
1926                        if (p->unregistering)
1927                                continue;
1928                        try_attach(p, header);
1929                }
1930        }
1931        header->parent->count++;
1932        list_add_tail(&header->ctl_entry, &header->set->list);
1933        spin_unlock(&sysctl_lock);
1934
1935        return header;
1936}
1937
1938/**
1939 * register_sysctl_table_path - register a sysctl table hierarchy
1940 * @path: The path to the directory the sysctl table is in.
1941 * @table: the top-level table structure
1942 *
1943 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1944 * array. A completely 0 filled entry terminates the table.
1945 *
1946 * See __register_sysctl_paths for more details.
1947 */
1948struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1949                                                struct ctl_table *table)
1950{
1951        return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1952                                        path, table);
1953}
1954
1955/**
1956 * register_sysctl_table - register a sysctl table hierarchy
1957 * @table: the top-level table structure
1958 *
1959 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1960 * array. A completely 0 filled entry terminates the table.
1961 *
1962 * See register_sysctl_paths for more details.
1963 */
1964struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1965{
1966        static const struct ctl_path null_path[] = { {} };
1967
1968        return register_sysctl_paths(null_path, table);
1969}
1970
1971/**
1972 * unregister_sysctl_table - unregister a sysctl table hierarchy
1973 * @header: the header returned from register_sysctl_table
1974 *
1975 * Unregisters the sysctl table and all children. proc entries may not
1976 * actually be removed until they are no longer used by anyone.
1977 */
1978void unregister_sysctl_table(struct ctl_table_header * header)
1979{
1980        might_sleep();
1981
1982        if (header == NULL)
1983                return;
1984
1985        spin_lock(&sysctl_lock);
1986        start_unregistering(header);
1987        if (!--header->parent->count) {
1988                WARN_ON(1);
1989                kfree_rcu(header->parent, rcu);
1990        }
1991        if (!--header->count)
1992                kfree_rcu(header, rcu);
1993        spin_unlock(&sysctl_lock);
1994}
1995
1996int sysctl_is_seen(struct ctl_table_header *p)
1997{
1998        struct ctl_table_set *set = p->set;
1999        int res;
2000        spin_lock(&sysctl_lock);
2001        if (p->unregistering)
2002                res = 0;
2003        else if (!set->is_seen)
2004                res = 1;
2005        else
2006                res = set->is_seen(set);
2007        spin_unlock(&sysctl_lock);
2008        return res;
2009}
2010
2011void setup_sysctl_set(struct ctl_table_set *p,
2012        struct ctl_table_set *parent,
2013        int (*is_seen)(struct ctl_table_set *))
2014{
2015        INIT_LIST_HEAD(&p->list);
2016        p->parent = parent ? parent : &sysctl_table_root.default_set;
2017        p->is_seen = is_seen;
2018}
2019
2020#else /* !CONFIG_SYSCTL */
2021struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2022{
2023        return NULL;
2024}
2025
2026struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2027                                                    struct ctl_table *table)
2028{
2029        return NULL;
2030}
2031
2032void unregister_sysctl_table(struct ctl_table_header * table)
2033{
2034}
2035
2036void setup_sysctl_set(struct ctl_table_set *p,
2037        struct ctl_table_set *parent,
2038        int (*is_seen)(struct ctl_table_set *))
2039{
2040}
2041
2042void sysctl_head_put(struct ctl_table_header *head)
2043{
2044}
2045
2046#endif /* CONFIG_SYSCTL */
2047
2048/*
2049 * /proc/sys support
2050 */
2051
2052#ifdef CONFIG_PROC_SYSCTL
2053
2054static int _proc_do_string(void* data, int maxlen, int write,
2055                           void __user *buffer,
2056                           size_t *lenp, loff_t *ppos)
2057{
2058        size_t len;
2059        char __user *p;
2060        char c;
2061
2062        if (!data || !maxlen || !*lenp) {
2063                *lenp = 0;
2064                return 0;
2065        }
2066
2067        if (write) {
2068                len = 0;
2069                p = buffer;
2070                while (len < *lenp) {
2071                        if (get_user(c, p++))
2072                                return -EFAULT;
2073                        if (c == 0 || c == '\n')
2074                                break;
2075                        len++;
2076                }
2077                if (len >= maxlen)
2078                        len = maxlen-1;
2079                if(copy_from_user(data, buffer, len))
2080                        return -EFAULT;
2081                ((char *) data)[len] = 0;
2082                *ppos += *lenp;
2083        } else {
2084                len = strlen(data);
2085                if (len > maxlen)
2086                        len = maxlen;
2087
2088                if (*ppos > len) {
2089                        *lenp = 0;
2090                        return 0;
2091                }
2092
2093                data += *ppos;
2094                len  -= *ppos;
2095
2096                if (len > *lenp)
2097                        len = *lenp;
2098                if (len)
2099                        if(copy_to_user(buffer, data, len))
2100                                return -EFAULT;
2101                if (len < *lenp) {
2102                        if(put_user('\n', ((char __user *) buffer) + len))
2103                                return -EFAULT;
2104                        len++;
2105                }
2106                *lenp = len;
2107                *ppos += len;
2108        }
2109        return 0;
2110}
2111
2112/**
2113 * proc_dostring - read a string sysctl
2114 * @table: the sysctl table
2115 * @write: %TRUE if this is a write to the sysctl file
2116 * @buffer: the user buffer
2117 * @lenp: the size of the user buffer
2118 * @ppos: file position
2119 *
2120 * Reads/writes a string from/to the user buffer. If the kernel
2121 * buffer provided is not large enough to hold the string, the
2122 * string is truncated. The copied string is %NULL-terminated.
2123 * If the string is being read by the user process, it is copied
2124 * and a newline '\n' is added. It is truncated if the buffer is
2125 * not large enough.
2126 *
2127 * Returns 0 on success.
2128 */
2129int proc_dostring(struct ctl_table *table, int write,
2130                  void __user *buffer, size_t *lenp, loff_t *ppos)
2131{
2132        return _proc_do_string(table->data, table->maxlen, write,
2133                               buffer, lenp, ppos);
2134}
2135
2136static size_t proc_skip_spaces(char **buf)
2137{
2138        size_t ret;
2139        char *tmp = skip_spaces(*buf);
2140        ret = tmp - *buf;
2141        *buf = tmp;
2142        return ret;
2143}
2144
2145static void proc_skip_char(char **buf, size_t *size, const char v)
2146{
2147        while (*size) {
2148                if (**buf != v)
2149                        break;
2150                (*size)--;
2151                (*buf)++;
2152        }
2153}
2154
2155#define TMPBUFLEN 22
2156/**
2157 * proc_get_long - reads an ASCII formatted integer from a user buffer
2158 *
2159 * @buf: a kernel buffer
2160 * @size: size of the kernel buffer
2161 * @val: this is where the number will be stored
2162 * @neg: set to %TRUE if number is negative
2163 * @perm_tr: a vector which contains the allowed trailers
2164 * @perm_tr_len: size of the perm_tr vector
2165 * @tr: pointer to store the trailer character
2166 *
2167 * In case of success %0 is returned and @buf and @size are updated with
2168 * the amount of bytes read. If @tr is non-NULL and a trailing
2169 * character exists (size is non-zero after returning from this
2170 * function), @tr is updated with the trailing character.
2171 */
2172static int proc_get_long(char **buf, size_t *size,
2173                          unsigned long *val, bool *neg,
2174                          const char *perm_tr, unsigned perm_tr_len, char *tr)
2175{
2176        int len;
2177        char *p, tmp[TMPBUFLEN];
2178
2179        if (!*size)
2180                return -EINVAL;
2181
2182        len = *size;
2183        if (len > TMPBUFLEN - 1)
2184                len = TMPBUFLEN - 1;
2185
2186        memcpy(tmp, *buf, len);
2187
2188        tmp[len] = 0;
2189        p = tmp;
2190        if (*p == '-' && *size > 1) {
2191                *neg = true;
2192                p++;
2193        } else
2194                *neg = false;
2195        if (!isdigit(*p))
2196                return -EINVAL;
2197
2198        *val = simple_strtoul(p, &p, 0);
2199
2200        len = p - tmp;
2201
2202        /* We don't know if the next char is whitespace thus we may accept
2203         * invalid integers (e.g. 1234...a) or two integers instead of one
2204         * (e.g. 123...1). So lets not allow such large numbers. */
2205        if (len == TMPBUFLEN - 1)
2206                return -EINVAL;
2207
2208        if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2209                return -EINVAL;
2210
2211        if (tr && (len < *size))
2212                *tr = *p;
2213
2214        *buf += len;
2215        *size -= len;
2216
2217        return 0;
2218}
2219
2220/**
2221 * proc_put_long - converts an integer to a decimal ASCII formatted string
2222 *
2223 * @buf: the user buffer
2224 * @size: the size of the user buffer
2225 * @val: the integer to be converted
2226 * @neg: sign of the number, %TRUE for negative
2227 *
2228 * In case of success %0 is returned and @buf and @size are updated with
2229 * the amount of bytes written.
2230 */
2231static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2232                          bool neg)
2233{
2234        int len;
2235        char tmp[TMPBUFLEN], *p = tmp;
2236
2237        sprintf(p, "%s%lu", neg ? "-" : "", val);
2238        len = strlen(tmp);
2239        if (len > *size)
2240                len = *size;
2241        if (copy_to_user(*buf, tmp, len))
2242                return -EFAULT;
2243        *size -= len;
2244        *buf += len;
2245        return 0;
2246}
2247#undef TMPBUFLEN
2248
2249static int proc_put_char(void __user **buf, size_t *size, char c)
2250{
2251        if (*size) {
2252                char __user **buffer = (char __user **)buf;
2253                if (put_user(c, *buffer))
2254                        return -EFAULT;
2255                (*size)--, (*buffer)++;
2256                *buf = *buffer;
2257        }
2258        return 0;
2259}
2260
2261static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2262                                 int *valp,
2263                                 int write, void *data)
2264{
2265        if (write) {
2266                *valp = *negp ? -*lvalp : *lvalp;
2267        } else {
2268                int val = *valp;
2269                if (val < 0) {
2270                        *negp = true;
2271                        *lvalp = (unsigned long)-val;
2272                } else {
2273                        *negp = false;
2274                        *lvalp = (unsigned long)val;
2275                }
2276        }
2277        return 0;
2278}
2279
2280static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2281
2282static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2283                  int write, void __user *buffer,
2284                  size_t *lenp, loff_t *ppos,
2285                  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2286                              int write, void *data),
2287                  void *data)
2288{
2289        int *i, vleft, first = 1, err = 0;
2290        unsigned long page = 0;
2291        size_t left;
2292        char *kbuf;
2293        
2294        if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2295                *lenp = 0;
2296                return 0;
2297        }
2298        
2299        i = (int *) tbl_data;
2300        vleft = table->maxlen / sizeof(*i);
2301        left = *lenp;
2302
2303        if (!conv)
2304                conv = do_proc_dointvec_conv;
2305
2306        if (write) {
2307                if (left > PAGE_SIZE - 1)
2308                        left = PAGE_SIZE - 1;
2309                page = __get_free_page(GFP_TEMPORARY);
2310                kbuf = (char *) page;
2311                if (!kbuf)
2312                        return -ENOMEM;
2313                if (copy_from_user(kbuf, buffer, left)) {
2314                        err = -EFAULT;
2315                        goto free;
2316                }
2317                kbuf[left] = 0;
2318        }
2319
2320        for (; left && vleft--; i++, first=0) {
2321                unsigned long lval;
2322                bool neg;
2323
2324                if (write) {
2325                        left -= proc_skip_spaces(&kbuf);
2326
2327                        if (!left)
2328                                break;
2329                        err = proc_get_long(&kbuf, &left, &lval, &neg,
2330                                             proc_wspace_sep,
2331                                             sizeof(proc_wspace_sep), NULL);
2332                        if (err)
2333                                break;
2334                        if (conv(&neg, &lval, i, 1, data)) {
2335                                err = -EINVAL;
2336                                break;
2337                        }
2338                } else {
2339                        if (conv(&neg, &lval, i, 0, data)) {
2340                                err = -EINVAL;
2341                                break;
2342                        }
2343                        if (!first)
2344                                err = proc_put_char(&buffer, &left, '\t');
2345                        if (err)
2346                                break;
2347                        err = proc_put_long(&buffer, &left, lval, neg);
2348                        if (err)
2349                                break;
2350                }
2351        }
2352
2353        if (!write && !first && left && !err)
2354                err = proc_put_char(&buffer, &left, '\n');
2355        if (write && !err && left)
2356                left -= proc_skip_spaces(&kbuf);
2357free:
2358        if (write) {
2359                free_page(page);
2360                if (first)
2361                        return err ? : -EINVAL;
2362        }
2363        *lenp -= left;
2364        *ppos += *lenp;
2365        return err;
2366}
2367
2368static int do_proc_dointvec(struct ctl_table *table, int write,
2369                  void __user *buffer, size_t *lenp, loff_t *ppos,
2370                  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2371                              int write, void *data),
2372                  void *data)
2373{
2374        return __do_proc_dointvec(table->data, table, write,
2375                        buffer, lenp, ppos, conv, data);
2376}
2377
2378/**
2379 * proc_dointvec - read a vector of integers
2380 * @table: the sysctl table
2381 * @write: %TRUE if this is a write to the sysctl file
2382 * @buffer: the user buffer
2383 * @lenp: the size of the user buffer
2384 * @ppos: file position
2385 *
2386 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2387 * values from/to the user buffer, treated as an ASCII string. 
2388 *
2389 * Returns 0 on success.
2390 */
2391int proc_dointvec(struct ctl_table *table, int write,
2392                     void __user *buffer, size_t *lenp, loff_t *ppos)
2393{
2394    return do_proc_dointvec(table,write,buffer,lenp,ppos,
2395                            NULL,NULL);
2396}
2397
2398/*
2399 * Taint values can only be increased
2400 * This means we can safely use a temporary.
2401 */
2402static int proc_taint(struct ctl_table *table, int write,
2403                               void __user *buffer, size_t *lenp, loff_t *ppos)
2404{
2405        struct ctl_table t;
2406        unsigned long tmptaint = get_taint();
2407        int err;
2408
2409        if (write && !capable(CAP_SYS_ADMIN))
2410                return -EPERM;
2411
2412        t = *table;
2413        t.data = &tmptaint;
2414        err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2415        if (err < 0)
2416                return err;
2417
2418        if (write) {
2419                /*
2420                 * Poor man's atomic or. Not worth adding a primitive
2421                 * to everyone's atomic.h for this
2422                 */
2423                int i;
2424                for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2425                        if ((tmptaint >> i) & 1)
2426                                add_taint(i);
2427                }
2428        }
2429
2430        return err;
2431}
2432
2433#ifdef CONFIG_PRINTK
2434static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2435                                void __user *buffer, size_t *lenp, loff_t *ppos)
2436{
2437        if (write && !capable(CAP_SYS_ADMIN))
2438                return -EPERM;
2439
2440        return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2441}
2442#endif
2443
2444struct do_proc_dointvec_minmax_conv_param {
2445        int *min;
2446        int *max;
2447};
2448
2449static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2450                                        int *valp,
2451                                        int write, void *data)
2452{
2453        struct do_proc_dointvec_minmax_conv_param *param = data;
2454        if (write) {
2455                int val = *negp ? -*lvalp : *lvalp;
2456                if ((param->min && *param->min > val) ||
2457                    (param->max && *param->max < val))
2458                        return -EINVAL;
2459                *valp = val;
2460        } else {
2461                int val = *valp;
2462                if (val < 0) {
2463                        *negp = true;
2464                        *lvalp = (unsigned long)-val;
2465                } else {
2466                        *negp = false;
2467                        *lvalp = (unsigned long)val;
2468                }
2469        }
2470        return 0;
2471}
2472
2473/**
2474 * proc_dointvec_minmax - read a vector of integers with min/max values
2475 * @table: the sysctl table
2476 * @write: %TRUE if this is a write to the sysctl file
2477 * @buffer: the user buffer
2478 * @lenp: the size of the user buffer
2479 * @ppos: file position
2480 *
2481 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2482 * values from/to the user buffer, treated as an ASCII string.
2483 *
2484 * This routine will ensure the values are within the range specified by
2485 * table->extra1 (min) and table->extra2 (max).
2486 *
2487 * Returns 0 on success.
2488 */
2489int proc_dointvec_minmax(struct ctl_table *table, int write,
2490                  void __user *buffer, size_t *lenp, loff_t *ppos)
2491{
2492        struct do_proc_dointvec_minmax_conv_param param = {
2493                .min = (int *) table->extra1,
2494                .max = (int *) table->extra2,
2495        };
2496        return do_proc_dointvec(table, write, buffer, lenp, ppos,
2497                                do_proc_dointvec_minmax_conv, &param);
2498}
2499
2500static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2501                                     void __user *buffer,
2502                                     size_t *lenp, loff_t *ppos,
2503                                     unsigned long convmul,
2504                                     unsigned long convdiv)
2505{
2506        unsigned long *i, *min, *max;
2507        int vleft, first = 1, err = 0;
2508        unsigned long page = 0;
2509        size_t left;
2510        char *kbuf;
2511
2512        if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2513                *lenp = 0;
2514                return 0;
2515        }
2516
2517        i = (unsigned long *) data;
2518        min = (unsigned long *) table->extra1;
2519        max = (unsigned long *) table->extra2;
2520        vleft = table->maxlen / sizeof(unsigned long);
2521        left = *lenp;
2522
2523        if (write) {
2524                if (left > PAGE_SIZE - 1)
2525                        left = PAGE_SIZE - 1;
2526                page = __get_free_page(GFP_TEMPORARY);
2527                kbuf = (char *) page;
2528                if (!kbuf)
2529                        return -ENOMEM;
2530                if (copy_from_user(kbuf, buffer, left)) {
2531                        err = -EFAULT;
2532                        goto free;
2533                }
2534                kbuf[left] = 0;
2535        }
2536
2537        for (; left && vleft--; i++, first = 0) {
2538                unsigned long val;
2539
2540                if (write) {
2541                        bool neg;
2542
2543                        left -= proc_skip_spaces(&kbuf);
2544
2545                        err = proc_get_long(&kbuf, &left, &val, &neg,
2546                                             proc_wspace_sep,
2547                                             sizeof(proc_wspace_sep), NULL);
2548                        if (err)
2549                                break;
2550                        if (neg)
2551                                continue;
2552                        if ((min && val < *min) || (max && val > *max))
2553                                continue;
2554                        *i = val;
2555                } else {
2556                        val = convdiv * (*i) / convmul;
2557                        if (!first)
2558                                err = proc_put_char(&buffer, &left, '\t');
2559                        err = proc_put_long(&buffer, &left, val, false);
2560                        if (err)
2561                                break;
2562                }
2563        }
2564
2565        if (!write && !first && left && !err)
2566                err = proc_put_char(&buffer, &left, '\n');
2567        if (write && !err)
2568                left -= proc_skip_spaces(&kbuf);
2569free:
2570        if (write) {
2571                free_page(page);
2572                if (first)
2573                        return err ? : -EINVAL;
2574        }
2575        *lenp -= left;
2576        *ppos += *lenp;
2577        return err;
2578}
2579
2580static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2581                                     void __user *buffer,
2582                                     size_t *lenp, loff_t *ppos,
2583                                     unsigned long convmul,
2584                                     unsigned long convdiv)
2585{
2586        return __do_proc_doulongvec_minmax(table->data, table, write,
2587                        buffer, lenp, ppos, convmul, convdiv);
2588}
2589
2590/**
2591 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2592 * @table: the sysctl table
2593 * @write: %TRUE if this is a write to the sysctl file
2594 * @buffer: the user buffer
2595 * @lenp: the size of the user buffer
2596 * @ppos: file position
2597 *
2598 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2599 * values from/to the user buffer, treated as an ASCII string.
2600 *
2601 * This routine will ensure the values are within the range specified by
2602 * table->extra1 (min) and table->extra2 (max).
2603 *
2604 * Returns 0 on success.
2605 */
2606int proc_doulongvec_minmax(struct ctl_table *table, int write,
2607                           void __user *buffer, size_t *lenp, loff_t *ppos)
2608{
2609    return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2610}
2611
2612/**
2613 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2614 * @table: the sysctl table
2615 * @write: %TRUE if this is a write to the sysctl file
2616 * @buffer: the user buffer
2617 * @lenp: the size of the user buffer
2618 * @ppos: file position
2619 *
2620 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2621 * values from/to the user buffer, treated as an ASCII string. The values
2622 * are treated as milliseconds, and converted to jiffies when they are stored.
2623 *
2624 * This routine will ensure the values are within the range specified by
2625 * table->extra1 (min) and table->extra2 (max).
2626 *
2627 * Returns 0 on success.
2628 */
2629int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2630                                      void __user *buffer,
2631                                      size_t *lenp, loff_t *ppos)
2632{
2633    return do_proc_doulongvec_minmax(table, write, buffer,
2634                                     lenp, ppos, HZ, 1000l);
2635}
2636
2637
2638static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2639                                         int *valp,
2640                                         int write, void *data)
2641{
2642        if (write) {
2643                if (*lvalp > LONG_MAX / HZ)
2644                        return 1;
2645                *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2646        } else {
2647                int val = *valp;
2648                unsigned long lval;
2649                if (val < 0) {
2650                        *negp = true;
2651                        lval = (unsigned long)-val;
2652                } else {
2653                        *negp = false;
2654                        lval = (unsigned long)val;
2655                }
2656                *lvalp = lval / HZ;
2657        }
2658        return 0;
2659}
2660
2661static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2662                                                int *valp,
2663                                                int write, void *data)
2664{
2665        if (write) {
2666                if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2667                        return 1;
2668                *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2669        } else {
2670                int val = *valp;
2671                unsigned long lval;
2672                if (val < 0) {
2673                        *negp = true;
2674                        lval = (unsigned long)-val;
2675                } else {
2676                        *negp = false;
2677                        lval = (unsigned long)val;
2678                }
2679                *lvalp = jiffies_to_clock_t(lval);
2680        }
2681        return 0;
2682}
2683
2684static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2685                                            int *valp,
2686                                            int write, void *data)
2687{
2688        if (write) {
2689                *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2690        } else {
2691                int val = *valp;
2692                unsigned long lval;
2693                if (val < 0) {
2694                        *negp = true;
2695                        lval = (unsigned long)-val;
2696                } else {
2697                        *negp = false;
2698                        lval = (unsigned long)val;
2699                }
2700                *lvalp = jiffies_to_msecs(lval);
2701        }
2702        return 0;
2703}
2704
2705/**
2706 * proc_dointvec_jiffies - read a vector of integers as seconds
2707 * @table: the sysctl table
2708 * @write: %TRUE if this is a write to the sysctl file
2709 * @buffer: the user buffer
2710 * @lenp: the size of the user buffer
2711 * @ppos: file position
2712 *
2713 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2714 * values from/to the user buffer, treated as an ASCII string. 
2715 * The values read are assumed to be in seconds, and are converted into
2716 * jiffies.
2717 *
2718 * Returns 0 on success.
2719 */
2720int proc_dointvec_jiffies(struct ctl_table *table, int write,
2721                          void __user *buffer, size_t *lenp, loff_t *ppos)
2722{
2723    return do_proc_dointvec(table,write,buffer,lenp,ppos,
2724                            do_proc_dointvec_jiffies_conv,NULL);
2725}
2726
2727/**
2728 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2729 * @table: the sysctl table
2730 * @write: %TRUE if this is a write to the sysctl file
2731 * @buffer: the user buffer
2732 * @lenp: the size of the user buffer
2733 * @ppos: pointer to the file position
2734 *
2735 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2736 * values from/to the user buffer, treated as an ASCII string. 
2737 * The values read are assumed to be in 1/USER_HZ seconds, and 
2738 * are converted into jiffies.
2739 *
2740 * Returns 0 on success.
2741 */
2742int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2743                                 void __user *buffer, size_t *lenp, loff_t *ppos)
2744{
2745    return do_proc_dointvec(table,write,buffer,lenp,ppos,
2746                            do_proc_dointvec_userhz_jiffies_conv,NULL);
2747}
2748
2749/**
2750 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2751 * @table: the sysctl table
2752 * @write: %TRUE if this is a write to the sysctl file
2753 * @buffer: the user buffer
2754 * @lenp: the size of the user buffer
2755 * @ppos: file position
2756 * @ppos: the current position in the file
2757 *
2758 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2759 * values from/to the user buffer, treated as an ASCII string. 
2760 * The values read are assumed to be in 1/1000 seconds, and 
2761 * are converted into jiffies.
2762 *
2763 * Returns 0 on success.
2764 */
2765int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2766                             void __user *buffer, size_t *lenp, loff_t *ppos)
2767{
2768        return do_proc_dointvec(table, write, buffer, lenp, ppos,
2769                                do_proc_dointvec_ms_jiffies_conv, NULL);
2770}
2771
2772static int proc_do_cad_pid(struct ctl_table *table, int write,
2773                           void __user *buffer, size_t *lenp, loff_t *ppos)
2774{
2775        struct pid *new_pid;
2776        pid_t tmp;
2777        int r;
2778
2779        tmp = pid_vnr(cad_pid);
2780
2781        r = __do_proc_dointvec(&tmp, table, write, buffer,
2782                               lenp, ppos, NULL, NULL);
2783        if (r || !write)
2784                return r;
2785
2786        new_pid = find_get_pid(tmp);
2787        if (!new_pid)
2788                return -ESRCH;
2789
2790        put_pid(xchg(&cad_pid, new_pid));
2791        return 0;
2792}
2793
2794/**
2795 * proc_do_large_bitmap - read/write from/to a large bitmap
2796 * @table: the sysctl table
2797 * @write: %TRUE if this is a write to the sysctl file
2798 * @buffer: the user buffer
2799 * @lenp: the size of the user buffer
2800 * @ppos: file position
2801 *
2802 * The bitmap is stored at table->data and the bitmap length (in bits)
2803 * in table->maxlen.
2804 *
2805 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2806 * large bitmaps may be represented in a compact manner. Writing into
2807 * the file will clear the bitmap then update it with the given input.
2808 *
2809 * Returns 0 on success.
2810 */
2811int proc_do_large_bitmap(struct ctl_table *table, int write,
2812                         void __user *buffer, size_t *lenp, loff_t *ppos)
2813{
2814        int err = 0;
2815        bool first = 1;
2816        size_t left = *lenp;
2817        unsigned long bitmap_len = table->maxlen;
2818        unsigned long *bitmap = (unsigned long *) table->data;
2819        unsigned long *tmp_bitmap = NULL;
2820        char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2821
2822        if (!bitmap_len || !left || (*ppos && !write)) {
2823                *lenp = 0;
2824                return 0;
2825        }
2826
2827        if (write) {
2828                unsigned long page = 0;
2829                char *kbuf;
2830
2831                if (left > PAGE_SIZE - 1)
2832                        left = PAGE_SIZE - 1;
2833
2834                page = __get_free_page(GFP_TEMPORARY);
2835                kbuf = (char *) page;
2836                if (!kbuf)
2837                        return -ENOMEM;
2838                if (copy_from_user(kbuf, buffer, left)) {
2839                        free_page(page);
2840                        return -EFAULT;
2841                }
2842                kbuf[left] = 0;
2843
2844                tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2845                                     GFP_KERNEL);
2846                if (!tmp_bitmap) {
2847                        free_page(page);
2848                        return -ENOMEM;
2849                }
2850                proc_skip_char(&kbuf, &left, '\n');
2851                while (!err && left) {
2852                        unsigned long val_a, val_b;
2853                        bool neg;
2854
2855                        err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2856                                             sizeof(tr_a), &c);
2857                        if (err)
2858                                break;
2859                        if (val_a >= bitmap_len || neg) {
2860                                err = -EINVAL;
2861                                break;
2862                        }
2863
2864                        val_b = val_a;
2865                        if (left) {
2866                                kbuf++;
2867                                left--;
2868                        }
2869
2870                        if (c == '-') {
2871                                err = proc_get_long(&kbuf, &left, &val_b,
2872                                                     &neg, tr_b, sizeof(tr_b),
2873                                                     &c);
2874                                if (err)
2875                                        break;
2876                                if (val_b >= bitmap_len || neg ||
2877                                    val_a > val_b) {
2878                                        err = -EINVAL;
2879                                        break;
2880                                }
2881                                if (left) {
2882                                        kbuf++;
2883                                        left--;
2884                                }
2885                        }
2886
2887                        while (val_a <= val_b)
2888                                set_bit(val_a++, tmp_bitmap);
2889
2890                        first = 0;
2891                        proc_skip_char(&kbuf, &left, '\n');
2892                }
2893                free_page(page);
2894        } else {
2895                unsigned long bit_a, bit_b = 0;
2896
2897                while (left) {
2898                        bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2899                        if (bit_a >= bitmap_len)
2900                                break;
2901                        bit_b = find_next_zero_bit(bitmap, bitmap_len,
2902                                                   bit_a + 1) - 1;
2903
2904                        if (!first) {
2905                                err = proc_put_char(&buffer, &left, ',');
2906                                if (err)
2907                                        break;
2908                        }
2909                        err = proc_put_long(&buffer, &left, bit_a, false);
2910                        if (err)
2911                                break;
2912                        if (bit_a != bit_b) {
2913                                err = proc_put_char(&buffer, &left, '-');
2914                                if (err)
2915                                        break;
2916                                err = proc_put_long(&buffer, &left, bit_b, false);
2917                                if (err)
2918                                        break;
2919                        }
2920
2921                        first = 0; bit_b++;
2922                }
2923                if (!err)
2924                        err = proc_put_char(&buffer, &left, '\n');
2925        }
2926
2927        if (!err) {
2928                if (write) {
2929                        if (*ppos)
2930                                bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2931                        else
2932                                memcpy(bitmap, tmp_bitmap,
2933                                        BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
2934                }
2935                kfree(tmp_bitmap);
2936                *lenp -= left;
2937                *ppos += *lenp;
2938                return 0;
2939        } else {
2940                kfree(tmp_bitmap);
2941                return err;
2942        }
2943}
2944
2945#else /* CONFIG_PROC_SYSCTL */
2946
2947int proc_dostring(struct ctl_table *table, int write,
2948                  void __user *buffer, size_t *lenp, loff_t *ppos)
2949{
2950        return -ENOSYS;
2951}
2952
2953int proc_dointvec(struct ctl_table *table, int write,
2954                  void __user *buffer, size_t *lenp, loff_t *ppos)
2955{
2956        return -ENOSYS;
2957}
2958
2959int proc_dointvec_minmax(struct ctl_table *table, int write,
2960                    void __user *buffer, size_t *lenp, loff_t *ppos)
2961{
2962        return -ENOSYS;
2963}
2964
2965int proc_dointvec_jiffies(struct ctl_table *table, int write,
2966                    void __user *buffer, size_t *lenp, loff_t *ppos)
2967{
2968        return -ENOSYS;
2969}
2970
2971int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2972                    void __user *buffer, size_t *lenp, loff_t *ppos)
2973{
2974        return -ENOSYS;
2975}
2976
2977int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2978                             void __user *buffer, size_t *lenp, loff_t *ppos)
2979{
2980        return -ENOSYS;
2981}
2982
2983int proc_doulongvec_minmax(struct ctl_table *table, int write,
2984                    void __user *buffer, size_t *lenp, loff_t *ppos)
2985{
2986        return -ENOSYS;
2987}
2988
2989int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2990                                      void __user *buffer,
2991                                      size_t *lenp, loff_t *ppos)
2992{
2993    return -ENOSYS;
2994}
2995
2996
2997#endif /* CONFIG_PROC_SYSCTL */
2998
2999/*
3000 * No sense putting this after each symbol definition, twice,
3001 * exception granted :-)
3002 */
3003EXPORT_SYMBOL(proc_dointvec);
3004EXPORT_SYMBOL(proc_dointvec_jiffies);
3005EXPORT_SYMBOL(proc_dointvec_minmax);
3006EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3007EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3008EXPORT_SYMBOL(proc_dostring);
3009EXPORT_SYMBOL(proc_doulongvec_minmax);
3010EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3011EXPORT_SYMBOL(register_sysctl_table);
3012EXPORT_SYMBOL(register_sysctl_paths);
3013EXPORT_SYMBOL(unregister_sysctl_table);
3014