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