kernel/sysctl.c

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