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