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/smp_lock.h>
  31 #include <linux/fs.h>
  32 #include <linux/init.h>
  33 #include <linux/kernel.h>
  34 #include <linux/kobject.h>
  35 #include <linux/net.h>
  36 #include <linux/sysrq.h>
  37 #include <linux/highuid.h>
  38 #include <linux/writeback.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 static int deprecated_sysctl_warning(struct __sysctl_args *args);
  64
  65 #if defined(CONFIG_SYSCTL)
  66
  67 /* External variables not in a header file. */
  68 extern int C_A_D;
  69 extern int print_fatal_signals;
  70 extern int sysctl_overcommit_memory;
  71 extern int sysctl_overcommit_ratio;
  72 extern int sysctl_panic_on_oom;
  73 extern int sysctl_oom_kill_allocating_task;
  74 extern int sysctl_oom_dump_tasks;
  75 extern int max_threads;
  76 extern int core_uses_pid;
  77 extern int suid_dumpable;
  78 extern char core_pattern[];
  79 extern unsigned int core_pipe_limit;
  80 extern int pid_max;
  81 extern int min_free_kbytes;
  82 extern int pid_max_min, pid_max_max;
  83 extern int sysctl_drop_caches;
  84 extern int percpu_pagelist_fraction;
  85 extern int compat_log;
  86 extern int latencytop_enabled;
  87 extern int sysctl_nr_open_min, sysctl_nr_open_max;
  88 #ifndef CONFIG_MMU
  89 extern int sysctl_nr_trim_pages;
  90 #endif
  91 #ifdef CONFIG_RCU_TORTURE_TEST
  92 extern int rcutorture_runnable;
  93 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
  94 #ifdef CONFIG_BLOCK
  95 extern int blk_iopoll_enabled;
  96 #endif
  97
  98 /* Constants used for minimum and  maximum */
  99 #ifdef CONFIG_DETECT_SOFTLOCKUP
 100 static int sixty = 60;
 101 static int neg_one = -1;
 102 #endif
 103
 104 static int zero;
 105 static int __maybe_unused one = 1;
 106 static int __maybe_unused two = 2;
 107 static unsigned long one_ul = 1;
 108 static int one_hundred = 100;
 109 #ifdef CONFIG_PRINTK
 110 static int ten_thousand = 10000;
 111 #endif
 112
 113 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
 114 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
 115
 116 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 117 static int maxolduid = 65535;
 118 static int minolduid;
 119 static int min_percpu_pagelist_fract = 8;
 120
 121 static int ngroups_max = NGROUPS_MAX;
 122
 123 #ifdef CONFIG_MODULES
 124 extern char modprobe_path[];
 125 extern int modules_disabled;
 126 #endif
 127 #ifdef CONFIG_CHR_DEV_SG
 128 extern int sg_big_buff;
 129 #endif
 130
 131 #ifdef CONFIG_SPARC
 132 #include <asm/system.h>
 133 #endif
 134
 135 #ifdef CONFIG_SPARC64
 136 extern int sysctl_tsb_ratio;
 137 #endif
 138
 139 #ifdef __hppa__
 140 extern int pwrsw_enabled;
 141 extern int unaligned_enabled;
 142 #endif
 143
 144 #ifdef CONFIG_S390
 145 #ifdef CONFIG_MATHEMU
 146 extern int sysctl_ieee_emulation_warnings;
 147 #endif
 148 extern int sysctl_userprocess_debug;
 149 extern int spin_retry;
 150 #endif
 151
 152 #ifdef CONFIG_BSD_PROCESS_ACCT
 153 extern int acct_parm[];
 154 #endif
 155
 156 #ifdef CONFIG_IA64
 157 extern int no_unaligned_warning;
 158 extern int unaligned_dump_stack;
 159 #endif
 160
 161 #ifdef CONFIG_RT_MUTEXES
 162 extern int max_lock_depth;
 163 #endif
 164
 165 #ifdef CONFIG_PROC_SYSCTL
 166 static int proc_do_cad_pid(struct ctl_table *table, int write,
 167                   void __user *buffer, size_t *lenp, loff_t *ppos);
 168 static int proc_taint(struct ctl_table *table, int write,
 169                                void __user *buffer, size_t *lenp, loff_t *ppos);
 170 #endif
 171
 172 static struct ctl_table root_table[];
 173 static struct ctl_table_root sysctl_table_root;
 174 static struct ctl_table_header root_table_header = {
 175         .count = 1,
 176         .ctl_table = root_table,
 177         .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
 178         .root = &sysctl_table_root,
 179         .set = &sysctl_table_root.default_set,
 180 };
 181 static struct ctl_table_root sysctl_table_root = {
 182         .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
 183         .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
 184 };
 185
 186 static struct ctl_table kern_table[];
 187 static struct ctl_table vm_table[];
 188 static struct ctl_table fs_table[];
 189 static struct ctl_table debug_table[];
 190 static struct ctl_table dev_table[];
 191 extern struct ctl_table random_table[];
 192 #ifdef CONFIG_INOTIFY_USER
 193 extern struct ctl_table inotify_table[];
 194 #endif
 195 #ifdef CONFIG_EPOLL
 196 extern struct ctl_table epoll_table[];
 197 #endif
 198
 199 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 200 int sysctl_legacy_va_layout;
 201 #endif
 202
 203 extern int prove_locking;
 204 extern int lock_stat;
 205
 206 /* The default sysctl tables: */
 207
 208 static struct ctl_table root_table[] = {
 209         {
 210                 .ctl_name       = CTL_KERN,
 211                 .procname       = "kernel",
 212                 .mode           = 0555,
 213                 .child          = kern_table,
 214         },
 215         {
 216                 .ctl_name       = CTL_VM,
 217                 .procname       = "vm",
 218                 .mode           = 0555,
 219                 .child          = vm_table,
 220         },
 221         {
 222                 .ctl_name       = CTL_FS,
 223                 .procname       = "fs",
 224                 .mode           = 0555,
 225                 .child          = fs_table,
 226         },
 227         {
 228                 .ctl_name       = CTL_DEBUG,
 229                 .procname       = "debug",
 230                 .mode           = 0555,
 231                 .child          = debug_table,
 232         },
 233         {
 234                 .ctl_name       = CTL_DEV,
 235                 .procname       = "dev",
 236                 .mode           = 0555,
 237                 .child          = dev_table,
 238         },
 239 /*
 240  * NOTE: do not add new entries to this table unless you have read
 241  * Documentation/sysctl/ctl_unnumbered.txt
 242  */
 243         { .ctl_name = 0 }
 244 };
 245
 246 #ifdef CONFIG_SCHED_DEBUG
 247 static int min_sched_granularity_ns = 100000;           /* 100 usecs */
 248 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
 249 static int min_wakeup_granularity_ns;                   /* 0 usecs */
 250 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
 251 #endif
 252
 253 static struct ctl_table kern_table[] = {
 254         {
 255                 .ctl_name       = CTL_UNNUMBERED,
 256                 .procname       = "sched_child_runs_first",
 257                 .data           = &sysctl_sched_child_runs_first,
 258                 .maxlen         = sizeof(unsigned int),
 259                 .mode           = 0644,
 260                 .proc_handler   = &proc_dointvec,
 261         },
 262 #ifdef CONFIG_SCHED_DEBUG
 263         {
 264                 .ctl_name       = CTL_UNNUMBERED,
 265                 .procname       = "sched_min_granularity_ns",
 266                 .data           = &sysctl_sched_min_granularity,
 267                 .maxlen         = sizeof(unsigned int),
 268                 .mode           = 0644,
 269                 .proc_handler   = &sched_nr_latency_handler,
 270                 .strategy       = &sysctl_intvec,
 271                 .extra1         = &min_sched_granularity_ns,
 272                 .extra2         = &max_sched_granularity_ns,
 273         },
 274         {
 275                 .ctl_name       = CTL_UNNUMBERED,
 276                 .procname       = "sched_latency_ns",
 277                 .data           = &sysctl_sched_latency,
 278                 .maxlen         = sizeof(unsigned int),
 279                 .mode           = 0644,
 280                 .proc_handler   = &sched_nr_latency_handler,
 281                 .strategy       = &sysctl_intvec,
 282                 .extra1         = &min_sched_granularity_ns,
 283                 .extra2         = &max_sched_granularity_ns,
 284         },
 285         {
 286                 .ctl_name       = CTL_UNNUMBERED,
 287                 .procname       = "sched_wakeup_granularity_ns",
 288                 .data           = &sysctl_sched_wakeup_granularity,
 289                 .maxlen         = sizeof(unsigned int),
 290                 .mode           = 0644,
 291                 .proc_handler   = &proc_dointvec_minmax,
 292                 .strategy       = &sysctl_intvec,
 293                 .extra1         = &min_wakeup_granularity_ns,
 294                 .extra2         = &max_wakeup_granularity_ns,
 295         },
 296         {
 297                 .ctl_name       = CTL_UNNUMBERED,
 298                 .procname       = "sched_shares_ratelimit",
 299                 .data           = &sysctl_sched_shares_ratelimit,
 300                 .maxlen         = sizeof(unsigned int),
 301                 .mode           = 0644,
 302                 .proc_handler   = &proc_dointvec,
 303         },
 304         {
 305                 .ctl_name       = CTL_UNNUMBERED,
 306                 .procname       = "sched_shares_thresh",
 307                 .data           = &sysctl_sched_shares_thresh,
 308                 .maxlen         = sizeof(unsigned int),
 309                 .mode           = 0644,
 310                 .proc_handler   = &proc_dointvec_minmax,
 311                 .strategy       = &sysctl_intvec,
 312                 .extra1         = &zero,
 313         },
 314         {
 315                 .ctl_name       = CTL_UNNUMBERED,
 316                 .procname       = "sched_features",
 317                 .data           = &sysctl_sched_features,
 318                 .maxlen         = sizeof(unsigned int),
 319                 .mode           = 0644,
 320                 .proc_handler   = &proc_dointvec,
 321         },
 322         {
 323                 .ctl_name       = CTL_UNNUMBERED,
 324                 .procname       = "sched_migration_cost",
 325                 .data           = &sysctl_sched_migration_cost,
 326                 .maxlen         = sizeof(unsigned int),
 327                 .mode           = 0644,
 328                 .proc_handler   = &proc_dointvec,
 329         },
 330         {
 331                 .ctl_name       = CTL_UNNUMBERED,
 332                 .procname       = "sched_nr_migrate",
 333                 .data           = &sysctl_sched_nr_migrate,
 334                 .maxlen         = sizeof(unsigned int),
 335                 .mode           = 0644,
 336                 .proc_handler   = &proc_dointvec,
 337         },
 338         {
 339                 .ctl_name       = CTL_UNNUMBERED,
 340                 .procname       = "sched_time_avg",
 341                 .data           = &sysctl_sched_time_avg,
 342                 .maxlen         = sizeof(unsigned int),
 343                 .mode           = 0644,
 344                 .proc_handler   = &proc_dointvec,
 345         },
 346         {
 347                 .ctl_name       = CTL_UNNUMBERED,
 348                 .procname       = "timer_migration",
 349                 .data           = &sysctl_timer_migration,
 350                 .maxlen         = sizeof(unsigned int),
 351                 .mode           = 0644,
 352                 .proc_handler   = &proc_dointvec_minmax,
 353                 .strategy       = &sysctl_intvec,
 354                 .extra1         = &zero,
 355                 .extra2         = &one,
 356         },
 357 #endif
 358         {
 359                 .ctl_name       = CTL_UNNUMBERED,
 360                 .procname       = "sched_rt_period_us",
 361                 .data           = &sysctl_sched_rt_period,
 362                 .maxlen         = sizeof(unsigned int),
 363                 .mode           = 0644,
 364                 .proc_handler   = &sched_rt_handler,
 365         },
 366         {
 367                 .ctl_name       = CTL_UNNUMBERED,
 368                 .procname       = "sched_rt_runtime_us",
 369                 .data           = &sysctl_sched_rt_runtime,
 370                 .maxlen         = sizeof(int),
 371                 .mode           = 0644,
 372                 .proc_handler   = &sched_rt_handler,
 373         },
 374         {
 375                 .ctl_name       = CTL_UNNUMBERED,
 376                 .procname       = "sched_compat_yield",
 377                 .data           = &sysctl_sched_compat_yield,
 378                 .maxlen         = sizeof(unsigned int),
 379                 .mode           = 0644,
 380                 .proc_handler   = &proc_dointvec,
 381         },
 382 #ifdef CONFIG_PROVE_LOCKING
 383         {
 384                 .ctl_name       = CTL_UNNUMBERED,
 385                 .procname       = "prove_locking",
 386                 .data           = &prove_locking,
 387                 .maxlen         = sizeof(int),
 388                 .mode           = 0644,
 389                 .proc_handler   = &proc_dointvec,
 390         },
 391 #endif
 392 #ifdef CONFIG_LOCK_STAT
 393         {
 394                 .ctl_name       = CTL_UNNUMBERED,
 395                 .procname       = "lock_stat",
 396                 .data           = &lock_stat,
 397                 .maxlen         = sizeof(int),
 398                 .mode           = 0644,
 399                 .proc_handler   = &proc_dointvec,
 400         },
 401 #endif
 402         {
 403                 .ctl_name       = KERN_PANIC,
 404                 .procname       = "panic",
 405                 .data           = &panic_timeout,
 406                 .maxlen         = sizeof(int),
 407                 .mode           = 0644,
 408                 .proc_handler   = &proc_dointvec,
 409         },
 410         {
 411                 .ctl_name       = KERN_CORE_USES_PID,
 412                 .procname       = "core_uses_pid",
 413                 .data           = &core_uses_pid,
 414                 .maxlen         = sizeof(int),
 415                 .mode           = 0644,
 416                 .proc_handler   = &proc_dointvec,
 417         },
 418         {
 419                 .ctl_name       = KERN_CORE_PATTERN,
 420                 .procname       = "core_pattern",
 421                 .data           = core_pattern,
 422                 .maxlen         = CORENAME_MAX_SIZE,
 423                 .mode           = 0644,
 424                 .proc_handler   = &proc_dostring,
 425                 .strategy       = &sysctl_string,
 426         },
 427         {
 428                 .ctl_name       = CTL_UNNUMBERED,
 429                 .procname       = "core_pipe_limit",
 430                 .data           = &core_pipe_limit,
 431                 .maxlen         = sizeof(unsigned int),
 432                 .mode           = 0644,
 433                 .proc_handler   = &proc_dointvec,
 434         },
 435 #ifdef CONFIG_PROC_SYSCTL
 436         {
 437                 .procname       = "tainted",
 438                 .maxlen         = sizeof(long),
 439                 .mode           = 0644,
 440                 .proc_handler   = &proc_taint,
 441         },
 442 #endif
 443 #ifdef CONFIG_LATENCYTOP
 444         {
 445                 .procname       = "latencytop",
 446                 .data           = &latencytop_enabled,
 447                 .maxlen         = sizeof(int),
 448                 .mode           = 0644,
 449                 .proc_handler   = &proc_dointvec,
 450         },
 451 #endif
 452 #ifdef CONFIG_BLK_DEV_INITRD
 453         {
 454                 .ctl_name       = KERN_REALROOTDEV,
 455                 .procname       = "real-root-dev",
 456                 .data           = &real_root_dev,
 457                 .maxlen         = sizeof(int),
 458                 .mode           = 0644,
 459                 .proc_handler   = &proc_dointvec,
 460         },
 461 #endif
 462         {
 463                 .ctl_name       = CTL_UNNUMBERED,
 464                 .procname       = "print-fatal-signals",
 465                 .data           = &print_fatal_signals,
 466                 .maxlen         = sizeof(int),
 467                 .mode           = 0644,
 468                 .proc_handler   = &proc_dointvec,
 469         },
 470 #ifdef CONFIG_SPARC
 471         {
 472                 .ctl_name       = KERN_SPARC_REBOOT,
 473                 .procname       = "reboot-cmd",
 474                 .data           = reboot_command,
 475                 .maxlen         = 256,
 476                 .mode           = 0644,
 477                 .proc_handler   = &proc_dostring,
 478                 .strategy       = &sysctl_string,
 479         },
 480         {
 481                 .ctl_name       = KERN_SPARC_STOP_A,
 482                 .procname       = "stop-a",
 483                 .data           = &stop_a_enabled,
 484                 .maxlen         = sizeof (int),
 485                 .mode           = 0644,
 486                 .proc_handler   = &proc_dointvec,
 487         },
 488         {
 489                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 490                 .procname       = "scons-poweroff",
 491                 .data           = &scons_pwroff,
 492                 .maxlen         = sizeof (int),
 493                 .mode           = 0644,
 494                 .proc_handler   = &proc_dointvec,
 495         },
 496 #endif
 497 #ifdef CONFIG_SPARC64
 498         {
 499                 .ctl_name       = CTL_UNNUMBERED,
 500                 .procname       = "tsb-ratio",
 501                 .data           = &sysctl_tsb_ratio,
 502                 .maxlen         = sizeof (int),
 503                 .mode           = 0644,
 504                 .proc_handler   = &proc_dointvec,
 505         },
 506 #endif
 507 #ifdef __hppa__
 508         {
 509                 .ctl_name       = KERN_HPPA_PWRSW,
 510                 .procname       = "soft-power",
 511                 .data           = &pwrsw_enabled,
 512                 .maxlen         = sizeof (int),
 513                 .mode           = 0644,
 514                 .proc_handler   = &proc_dointvec,
 515         },
 516         {
 517                 .ctl_name       = KERN_HPPA_UNALIGNED,
 518                 .procname       = "unaligned-trap",
 519                 .data           = &unaligned_enabled,
 520                 .maxlen         = sizeof (int),
 521                 .mode           = 0644,
 522                 .proc_handler   = &proc_dointvec,
 523         },
 524 #endif
 525         {
 526                 .ctl_name       = KERN_CTLALTDEL,
 527                 .procname       = "ctrl-alt-del",
 528                 .data           = &C_A_D,
 529                 .maxlen         = sizeof(int),
 530                 .mode           = 0644,
 531                 .proc_handler   = &proc_dointvec,
 532         },
 533 #ifdef CONFIG_FUNCTION_TRACER
 534         {
 535                 .ctl_name       = CTL_UNNUMBERED,
 536                 .procname       = "ftrace_enabled",
 537                 .data           = &ftrace_enabled,
 538                 .maxlen         = sizeof(int),
 539                 .mode           = 0644,
 540                 .proc_handler   = &ftrace_enable_sysctl,
 541         },
 542 #endif
 543 #ifdef CONFIG_STACK_TRACER
 544         {
 545                 .ctl_name       = CTL_UNNUMBERED,
 546                 .procname       = "stack_tracer_enabled",
 547                 .data           = &stack_tracer_enabled,
 548                 .maxlen         = sizeof(int),
 549                 .mode           = 0644,
 550                 .proc_handler   = &stack_trace_sysctl,
 551         },
 552 #endif
 553 #ifdef CONFIG_TRACING
 554         {
 555                 .ctl_name       = CTL_UNNUMBERED,
 556                 .procname       = "ftrace_dump_on_oops",
 557                 .data           = &ftrace_dump_on_oops,
 558                 .maxlen         = sizeof(int),
 559                 .mode           = 0644,
 560                 .proc_handler   = &proc_dointvec,
 561         },
 562 #endif
 563 #ifdef CONFIG_MODULES
 564         {
 565                 .ctl_name       = KERN_MODPROBE,
 566                 .procname       = "modprobe",
 567                 .data           = &modprobe_path,
 568                 .maxlen         = KMOD_PATH_LEN,
 569                 .mode           = 0644,
 570                 .proc_handler   = &proc_dostring,
 571                 .strategy       = &sysctl_string,
 572         },
 573         {
 574                 .ctl_name       = CTL_UNNUMBERED,
 575                 .procname       = "modules_disabled",
 576                 .data           = &modules_disabled,
 577                 .maxlen         = sizeof(int),
 578                 .mode           = 0644,
 579                 /* only handle a transition from default "0" to "1" */
 580                 .proc_handler   = &proc_dointvec_minmax,
 581                 .extra1         = &one,
 582                 .extra2         = &one,
 583         },
 584 #endif
 585 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 586         {
 587                 .ctl_name       = KERN_HOTPLUG,
 588                 .procname       = "hotplug",
 589                 .data           = &uevent_helper,
 590                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 591                 .mode           = 0644,
 592                 .proc_handler   = &proc_dostring,
 593                 .strategy       = &sysctl_string,
 594         },
 595 #endif
 596 #ifdef CONFIG_CHR_DEV_SG
 597         {
 598                 .ctl_name       = KERN_SG_BIG_BUFF,
 599                 .procname       = "sg-big-buff",
 600                 .data           = &sg_big_buff,
 601                 .maxlen         = sizeof (int),
 602                 .mode           = 0444,
 603                 .proc_handler   = &proc_dointvec,
 604         },
 605 #endif
 606 #ifdef CONFIG_BSD_PROCESS_ACCT
 607         {
 608                 .ctl_name       = KERN_ACCT,
 609                 .procname       = "acct",
 610                 .data           = &acct_parm,
 611                 .maxlen         = 3*sizeof(int),
 612                 .mode           = 0644,
 613                 .proc_handler   = &proc_dointvec,
 614         },
 615 #endif
 616 #ifdef CONFIG_MAGIC_SYSRQ
 617         {
 618                 .ctl_name       = KERN_SYSRQ,
 619                 .procname       = "sysrq",
 620                 .data           = &__sysrq_enabled,
 621                 .maxlen         = sizeof (int),
 622                 .mode           = 0644,
 623                 .proc_handler   = &proc_dointvec,
 624         },
 625 #endif
 626 #ifdef CONFIG_PROC_SYSCTL
 627         {
 628                 .procname       = "cad_pid",
 629                 .data           = NULL,
 630                 .maxlen         = sizeof (int),
 631                 .mode           = 0600,
 632                 .proc_handler   = &proc_do_cad_pid,
 633         },
 634 #endif
 635         {
 636                 .ctl_name       = KERN_MAX_THREADS,
 637                 .procname       = "threads-max",
 638                 .data           = &max_threads,
 639                 .maxlen         = sizeof(int),
 640                 .mode           = 0644,
 641                 .proc_handler   = &proc_dointvec,
 642         },
 643         {
 644                 .ctl_name       = KERN_RANDOM,
 645                 .procname       = "random",
 646                 .mode           = 0555,
 647                 .child          = random_table,
 648         },
 649         {
 650                 .ctl_name       = KERN_OVERFLOWUID,
 651                 .procname       = "overflowuid",
 652                 .data           = &overflowuid,
 653                 .maxlen         = sizeof(int),
 654                 .mode           = 0644,
 655                 .proc_handler   = &proc_dointvec_minmax,
 656                 .strategy       = &sysctl_intvec,
 657                 .extra1         = &minolduid,
 658                 .extra2         = &maxolduid,
 659         },
 660         {
 661                 .ctl_name       = KERN_OVERFLOWGID,
 662                 .procname       = "overflowgid",
 663                 .data           = &overflowgid,
 664                 .maxlen         = sizeof(int),
 665                 .mode           = 0644,
 666                 .proc_handler   = &proc_dointvec_minmax,
 667                 .strategy       = &sysctl_intvec,
 668                 .extra1         = &minolduid,
 669                 .extra2         = &maxolduid,
 670         },
 671 #ifdef CONFIG_S390
 672 #ifdef CONFIG_MATHEMU
 673         {
 674                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 675                 .procname       = "ieee_emulation_warnings",
 676                 .data           = &sysctl_ieee_emulation_warnings,
 677                 .maxlen         = sizeof(int),
 678                 .mode           = 0644,
 679                 .proc_handler   = &proc_dointvec,
 680         },
 681 #endif
 682         {
 683                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 684                 .procname       = "userprocess_debug",
 685                 .data           = &sysctl_userprocess_debug,
 686                 .maxlen         = sizeof(int),
 687                 .mode           = 0644,
 688                 .proc_handler   = &proc_dointvec,
 689         },
 690 #endif
 691         {
 692                 .ctl_name       = KERN_PIDMAX,
 693                 .procname       = "pid_max",
 694                 .data           = &pid_max,
 695                 .maxlen         = sizeof (int),
 696                 .mode           = 0644,
 697                 .proc_handler   = &proc_dointvec_minmax,
 698                 .strategy       = sysctl_intvec,
 699                 .extra1         = &pid_max_min,
 700                 .extra2         = &pid_max_max,
 701         },
 702         {
 703                 .ctl_name       = KERN_PANIC_ON_OOPS,
 704                 .procname       = "panic_on_oops",
 705                 .data           = &panic_on_oops,
 706                 .maxlen         = sizeof(int),
 707                 .mode           = 0644,
 708                 .proc_handler   = &proc_dointvec,
 709         },
 710 #if defined CONFIG_PRINTK
 711         {
 712                 .ctl_name       = KERN_PRINTK,
 713                 .procname       = "printk",
 714                 .data           = &console_loglevel,
 715                 .maxlen         = 4*sizeof(int),
 716                 .mode           = 0644,
 717                 .proc_handler   = &proc_dointvec,
 718         },
 719         {
 720                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 721                 .procname       = "printk_ratelimit",
 722                 .data           = &printk_ratelimit_state.interval,
 723                 .maxlen         = sizeof(int),
 724                 .mode           = 0644,
 725                 .proc_handler   = &proc_dointvec_jiffies,
 726                 .strategy       = &sysctl_jiffies,
 727         },
 728         {
 729                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 730                 .procname       = "printk_ratelimit_burst",
 731                 .data           = &printk_ratelimit_state.burst,
 732                 .maxlen         = sizeof(int),
 733                 .mode           = 0644,
 734                 .proc_handler   = &proc_dointvec,
 735         },
 736         {
 737                 .ctl_name       = CTL_UNNUMBERED,
 738                 .procname       = "printk_delay",
 739                 .data           = &printk_delay_msec,
 740                 .maxlen         = sizeof(int),
 741                 .mode           = 0644,
 742                 .proc_handler   = &proc_dointvec_minmax,
 743                 .strategy       = &sysctl_intvec,
 744                 .extra1         = &zero,
 745                 .extra2         = &ten_thousand,
 746         },
 747 #endif
 748         {
 749                 .ctl_name       = KERN_NGROUPS_MAX,
 750                 .procname       = "ngroups_max",
 751                 .data           = &ngroups_max,
 752                 .maxlen         = sizeof (int),
 753                 .mode           = 0444,
 754                 .proc_handler   = &proc_dointvec,
 755         },
 756 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 757         {
 758                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 759                 .procname       = "unknown_nmi_panic",
 760                 .data           = &unknown_nmi_panic,
 761                 .maxlen         = sizeof (int),
 762                 .mode           = 0644,
 763                 .proc_handler   = &proc_dointvec,
 764         },
 765         {
 766                 .procname       = "nmi_watchdog",
 767                 .data           = &nmi_watchdog_enabled,
 768                 .maxlen         = sizeof (int),
 769                 .mode           = 0644,
 770                 .proc_handler   = &proc_nmi_enabled,
 771         },
 772 #endif
 773 #if defined(CONFIG_X86)
 774         {
 775                 .ctl_name       = KERN_PANIC_ON_NMI,
 776                 .procname       = "panic_on_unrecovered_nmi",
 777                 .data           = &panic_on_unrecovered_nmi,
 778                 .maxlen         = sizeof(int),
 779                 .mode           = 0644,
 780                 .proc_handler   = &proc_dointvec,
 781         },
 782         {
 783                 .ctl_name       = CTL_UNNUMBERED,
 784                 .procname       = "panic_on_io_nmi",
 785                 .data           = &panic_on_io_nmi,
 786                 .maxlen         = sizeof(int),
 787                 .mode           = 0644,
 788                 .proc_handler   = &proc_dointvec,
 789         },
 790         {
 791                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 792                 .procname       = "bootloader_type",
 793                 .data           = &bootloader_type,
 794                 .maxlen         = sizeof (int),
 795                 .mode           = 0444,
 796                 .proc_handler   = &proc_dointvec,
 797         },
 798         {
 799                 .ctl_name       = CTL_UNNUMBERED,
 800                 .procname       = "bootloader_version",
 801                 .data           = &bootloader_version,
 802                 .maxlen         = sizeof (int),
 803                 .mode           = 0444,
 804                 .proc_handler   = &proc_dointvec,
 805         },
 806         {
 807                 .ctl_name       = CTL_UNNUMBERED,
 808                 .procname       = "kstack_depth_to_print",
 809                 .data           = &kstack_depth_to_print,
 810                 .maxlen         = sizeof(int),
 811                 .mode           = 0644,
 812                 .proc_handler   = &proc_dointvec,
 813         },
 814         {
 815                 .ctl_name       = CTL_UNNUMBERED,
 816                 .procname       = "io_delay_type",
 817                 .data           = &io_delay_type,
 818                 .maxlen         = sizeof(int),
 819                 .mode           = 0644,
 820                 .proc_handler   = &proc_dointvec,
 821         },
 822 #endif
 823 #if defined(CONFIG_MMU)
 824         {
 825                 .ctl_name       = KERN_RANDOMIZE,
 826                 .procname       = "randomize_va_space",
 827                 .data           = &randomize_va_space,
 828                 .maxlen         = sizeof(int),
 829                 .mode           = 0644,
 830                 .proc_handler   = &proc_dointvec,
 831         },
 832 #endif
 833 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 834         {
 835                 .ctl_name       = KERN_SPIN_RETRY,
 836                 .procname       = "spin_retry",
 837                 .data           = &spin_retry,
 838                 .maxlen         = sizeof (int),
 839                 .mode           = 0644,
 840                 .proc_handler   = &proc_dointvec,
 841         },
 842 #endif
 843 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 844         {
 845                 .procname       = "acpi_video_flags",
 846                 .data           = &acpi_realmode_flags,
 847                 .maxlen         = sizeof (unsigned long),
 848                 .mode           = 0644,
 849                 .proc_handler   = &proc_doulongvec_minmax,
 850         },
 851 #endif
 852 #ifdef CONFIG_IA64
 853         {
 854                 .ctl_name       = KERN_IA64_UNALIGNED,
 855                 .procname       = "ignore-unaligned-usertrap",
 856                 .data           = &no_unaligned_warning,
 857                 .maxlen         = sizeof (int),
 858                 .mode           = 0644,
 859                 .proc_handler   = &proc_dointvec,
 860         },
 861         {
 862                 .ctl_name       = CTL_UNNUMBERED,
 863                 .procname       = "unaligned-dump-stack",
 864                 .data           = &unaligned_dump_stack,
 865                 .maxlen         = sizeof (int),
 866                 .mode           = 0644,
 867                 .proc_handler   = &proc_dointvec,
 868         },
 869 #endif
 870 #ifdef CONFIG_DETECT_SOFTLOCKUP
 871         {
 872                 .ctl_name       = CTL_UNNUMBERED,
 873                 .procname       = "softlockup_panic",
 874                 .data           = &softlockup_panic,
 875                 .maxlen         = sizeof(int),
 876                 .mode           = 0644,
 877                 .proc_handler   = &proc_dointvec_minmax,
 878                 .strategy       = &sysctl_intvec,
 879                 .extra1         = &zero,
 880                 .extra2         = &one,
 881         },
 882         {
 883                 .ctl_name       = CTL_UNNUMBERED,
 884                 .procname       = "softlockup_thresh",
 885                 .data           = &softlockup_thresh,
 886                 .maxlen         = sizeof(int),
 887                 .mode           = 0644,
 888                 .proc_handler   = &proc_dosoftlockup_thresh,
 889                 .strategy       = &sysctl_intvec,
 890                 .extra1         = &neg_one,
 891                 .extra2         = &sixty,
 892         },
 893 #endif
 894 #ifdef CONFIG_DETECT_HUNG_TASK
 895         {
 896                 .ctl_name       = CTL_UNNUMBERED,
 897                 .procname       = "hung_task_panic",
 898                 .data           = &sysctl_hung_task_panic,
 899                 .maxlen         = sizeof(int),
 900                 .mode           = 0644,
 901                 .proc_handler   = &proc_dointvec_minmax,
 902                 .strategy       = &sysctl_intvec,
 903                 .extra1         = &zero,
 904                 .extra2         = &one,
 905         },
 906         {
 907                 .ctl_name       = CTL_UNNUMBERED,
 908                 .procname       = "hung_task_check_count",
 909                 .data           = &sysctl_hung_task_check_count,
 910                 .maxlen         = sizeof(unsigned long),
 911                 .mode           = 0644,
 912                 .proc_handler   = &proc_doulongvec_minmax,
 913                 .strategy       = &sysctl_intvec,
 914         },
 915         {
 916                 .ctl_name       = CTL_UNNUMBERED,
 917                 .procname       = "hung_task_timeout_secs",
 918                 .data           = &sysctl_hung_task_timeout_secs,
 919                 .maxlen         = sizeof(unsigned long),
 920                 .mode           = 0644,
 921                 .proc_handler   = &proc_dohung_task_timeout_secs,
 922                 .strategy       = &sysctl_intvec,
 923         },
 924         {
 925                 .ctl_name       = CTL_UNNUMBERED,
 926                 .procname       = "hung_task_warnings",
 927                 .data           = &sysctl_hung_task_warnings,
 928                 .maxlen         = sizeof(unsigned long),
 929                 .mode           = 0644,
 930                 .proc_handler   = &proc_doulongvec_minmax,
 931                 .strategy       = &sysctl_intvec,
 932         },
 933 #endif
 934 #ifdef CONFIG_COMPAT
 935         {
 936                 .ctl_name       = KERN_COMPAT_LOG,
 937                 .procname       = "compat-log",
 938                 .data           = &compat_log,
 939                 .maxlen         = sizeof (int),
 940                 .mode           = 0644,
 941                 .proc_handler   = &proc_dointvec,
 942         },
 943 #endif
 944 #ifdef CONFIG_RT_MUTEXES
 945         {
 946                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 947                 .procname       = "max_lock_depth",
 948                 .data           = &max_lock_depth,
 949                 .maxlen         = sizeof(int),
 950                 .mode           = 0644,
 951                 .proc_handler   = &proc_dointvec,
 952         },
 953 #endif
 954         {
 955                 .ctl_name       = CTL_UNNUMBERED,
 956                 .procname       = "poweroff_cmd",
 957                 .data           = &poweroff_cmd,
 958                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 959                 .mode           = 0644,
 960                 .proc_handler   = &proc_dostring,
 961                 .strategy       = &sysctl_string,
 962         },
 963 #ifdef CONFIG_KEYS
 964         {
 965                 .ctl_name       = CTL_UNNUMBERED,
 966                 .procname       = "keys",
 967                 .mode           = 0555,
 968                 .child          = key_sysctls,
 969         },
 970 #endif
 971 #ifdef CONFIG_RCU_TORTURE_TEST
 972         {
 973                 .ctl_name       = CTL_UNNUMBERED,
 974                 .procname       = "rcutorture_runnable",
 975                 .data           = &rcutorture_runnable,
 976                 .maxlen         = sizeof(int),
 977                 .mode           = 0644,
 978                 .proc_handler   = &proc_dointvec,
 979         },
 980 #endif
 981 #ifdef CONFIG_SLOW_WORK
 982         {
 983                 .ctl_name       = CTL_UNNUMBERED,
 984                 .procname       = "slow-work",
 985                 .mode           = 0555,
 986                 .child          = slow_work_sysctls,
 987         },
 988 #endif
 989 #ifdef CONFIG_PERF_EVENTS
 990         {
 991                 .ctl_name       = CTL_UNNUMBERED,
 992                 .procname       = "perf_event_paranoid",
 993                 .data           = &sysctl_perf_event_paranoid,
 994                 .maxlen         = sizeof(sysctl_perf_event_paranoid),
 995                 .mode           = 0644,
 996                 .proc_handler   = &proc_dointvec,
 997         },
 998         {
 999                 .ctl_name       = CTL_UNNUMBERED,
1000                 .procname       = "perf_event_mlock_kb",
1001                 .data           = &sysctl_perf_event_mlock,
1002                 .maxlen         = sizeof(sysctl_perf_event_mlock),
1003                 .mode           = 0644,
1004                 .proc_handler   = &proc_dointvec,
1005         },
1006         {
1007                 .ctl_name       = CTL_UNNUMBERED,
1008                 .procname       = "perf_event_max_sample_rate",
1009                 .data           = &sysctl_perf_event_sample_rate,
1010                 .maxlen         = sizeof(sysctl_perf_event_sample_rate),
1011                 .mode           = 0644,
1012                 .proc_handler   = &proc_dointvec,
1013         },
1014 #endif
1015 #ifdef CONFIG_KMEMCHECK
1016         {
1017                 .ctl_name       = CTL_UNNUMBERED,
1018                 .procname       = "kmemcheck",
1019                 .data           = &kmemcheck_enabled,
1020                 .maxlen         = sizeof(int),
1021                 .mode           = 0644,
1022                 .proc_handler   = &proc_dointvec,
1023         },
1024 #endif
1025 #ifdef CONFIG_BLOCK
1026         {
1027                 .ctl_name       = CTL_UNNUMBERED,
1028                 .procname       = "blk_iopoll",
1029                 .data           = &blk_iopoll_enabled,
1030                 .maxlen         = sizeof(int),
1031                 .mode           = 0644,
1032                 .proc_handler   = &proc_dointvec,
1033         },
1034 #endif
1035 /*
1036  * NOTE: do not add new entries to this table unless you have read
1037  * Documentation/sysctl/ctl_unnumbered.txt
1038  */
1039         { .ctl_name = 0 }
1040 };
1041
1042 static struct ctl_table vm_table[] = {
1043         {
1044                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
1045                 .procname       = "overcommit_memory",
1046                 .data           = &sysctl_overcommit_memory,
1047                 .maxlen         = sizeof(sysctl_overcommit_memory),
1048                 .mode           = 0644,
1049                 .proc_handler   = &proc_dointvec,
1050         },
1051         {
1052                 .ctl_name       = VM_PANIC_ON_OOM,
1053                 .procname       = "panic_on_oom",
1054                 .data           = &sysctl_panic_on_oom,
1055                 .maxlen         = sizeof(sysctl_panic_on_oom),
1056                 .mode           = 0644,
1057                 .proc_handler   = &proc_dointvec,
1058         },
1059         {
1060                 .ctl_name       = CTL_UNNUMBERED,
1061                 .procname       = "oom_kill_allocating_task",
1062                 .data           = &sysctl_oom_kill_allocating_task,
1063                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
1064                 .mode           = 0644,
1065                 .proc_handler   = &proc_dointvec,
1066         },
1067         {
1068                 .ctl_name       = CTL_UNNUMBERED,
1069                 .procname       = "oom_dump_tasks",
1070                 .data           = &sysctl_oom_dump_tasks,
1071                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
1072                 .mode           = 0644,
1073                 .proc_handler   = &proc_dointvec,
1074         },
1075         {
1076                 .ctl_name       = VM_OVERCOMMIT_RATIO,
1077                 .procname       = "overcommit_ratio",
1078                 .data           = &sysctl_overcommit_ratio,
1079                 .maxlen         = sizeof(sysctl_overcommit_ratio),
1080                 .mode           = 0644,
1081                 .proc_handler   = &proc_dointvec,
1082         },
1083         {
1084                 .ctl_name       = VM_PAGE_CLUSTER,
1085                 .procname       = "page-cluster",
1086                 .data           = &page_cluster,
1087                 .maxlen         = sizeof(int),
1088                 .mode           = 0644,
1089                 .proc_handler   = &proc_dointvec,
1090         },
1091         {
1092                 .ctl_name       = VM_DIRTY_BACKGROUND,
1093                 .procname       = "dirty_background_ratio",
1094                 .data           = &dirty_background_ratio,
1095                 .maxlen         = sizeof(dirty_background_ratio),
1096                 .mode           = 0644,
1097                 .proc_handler   = &dirty_background_ratio_handler,
1098                 .strategy       = &sysctl_intvec,
1099                 .extra1         = &zero,
1100                 .extra2         = &one_hundred,
1101         },
1102         {
1103                 .ctl_name       = CTL_UNNUMBERED,
1104                 .procname       = "dirty_background_bytes",
1105                 .data           = &dirty_background_bytes,
1106                 .maxlen         = sizeof(dirty_background_bytes),
1107                 .mode           = 0644,
1108                 .proc_handler   = &dirty_background_bytes_handler,
1109                 .strategy       = &sysctl_intvec,
1110                 .extra1         = &one_ul,
1111         },
1112         {
1113                 .ctl_name       = VM_DIRTY_RATIO,
1114                 .procname       = "dirty_ratio",
1115                 .data           = &vm_dirty_ratio,
1116                 .maxlen         = sizeof(vm_dirty_ratio),
1117                 .mode           = 0644,
1118                 .proc_handler   = &dirty_ratio_handler,
1119                 .strategy       = &sysctl_intvec,
1120                 .extra1         = &zero,
1121                 .extra2         = &one_hundred,
1122         },
1123         {
1124                 .ctl_name       = CTL_UNNUMBERED,
1125                 .procname       = "dirty_bytes",
1126                 .data           = &vm_dirty_bytes,
1127                 .maxlen         = sizeof(vm_dirty_bytes),
1128                 .mode           = 0644,
1129                 .proc_handler   = &dirty_bytes_handler,
1130                 .strategy       = &sysctl_intvec,
1131                 .extra1         = &dirty_bytes_min,
1132         },
1133         {
1134                 .procname       = "dirty_writeback_centisecs",
1135                 .data           = &dirty_writeback_interval,
1136                 .maxlen         = sizeof(dirty_writeback_interval),
1137                 .mode           = 0644,
1138                 .proc_handler   = &dirty_writeback_centisecs_handler,
1139         },
1140         {
1141                 .procname       = "dirty_expire_centisecs",
1142                 .data           = &dirty_expire_interval,
1143                 .maxlen         = sizeof(dirty_expire_interval),
1144                 .mode           = 0644,
1145                 .proc_handler   = &proc_dointvec,
1146         },
1147         {
1148                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
1149                 .procname       = "nr_pdflush_threads",
1150                 .data           = &nr_pdflush_threads,
1151                 .maxlen         = sizeof nr_pdflush_threads,
1152                 .mode           = 0444 /* read-only*/,
1153                 .proc_handler   = &proc_dointvec,
1154         },
1155         {
1156                 .ctl_name       = VM_SWAPPINESS,
1157                 .procname       = "swappiness",
1158                 .data           = &vm_swappiness,
1159                 .maxlen         = sizeof(vm_swappiness),
1160                 .mode           = 0644,
1161                 .proc_handler   = &proc_dointvec_minmax,
1162                 .strategy       = &sysctl_intvec,
1163                 .extra1         = &zero,
1164                 .extra2         = &one_hundred,
1165         },
1166 #ifdef CONFIG_HUGETLB_PAGE
1167          {
1168                 .procname       = "nr_hugepages",
1169                 .data           = NULL,
1170                 .maxlen         = sizeof(unsigned long),
1171                 .mode           = 0644,
1172                 .proc_handler   = &hugetlb_sysctl_handler,
1173                 .extra1         = (void *)&hugetlb_zero,
1174                 .extra2         = (void *)&hugetlb_infinity,
1175          },
1176          {
1177                 .ctl_name       = VM_HUGETLB_GROUP,
1178                 .procname       = "hugetlb_shm_group",
1179                 .data           = &sysctl_hugetlb_shm_group,
1180                 .maxlen         = sizeof(gid_t),
1181                 .mode           = 0644,
1182                 .proc_handler   = &proc_dointvec,
1183          },
1184          {
1185                 .ctl_name       = CTL_UNNUMBERED,
1186                 .procname       = "hugepages_treat_as_movable",
1187                 .data           = &hugepages_treat_as_movable,
1188                 .maxlen         = sizeof(int),
1189                 .mode           = 0644,
1190                 .proc_handler   = &hugetlb_treat_movable_handler,
1191         },
1192         {
1193                 .ctl_name       = CTL_UNNUMBERED,
1194                 .procname       = "nr_overcommit_hugepages",
1195                 .data           = NULL,
1196                 .maxlen         = sizeof(unsigned long),
1197                 .mode           = 0644,
1198                 .proc_handler   = &hugetlb_overcommit_handler,
1199                 .extra1         = (void *)&hugetlb_zero,
1200                 .extra2         = (void *)&hugetlb_infinity,
1201         },
1202 #endif
1203         {
1204                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
1205                 .procname       = "lowmem_reserve_ratio",
1206                 .data           = &sysctl_lowmem_reserve_ratio,
1207                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1208                 .mode           = 0644,
1209                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
1210                 .strategy       = &sysctl_intvec,
1211         },
1212         {
1213                 .ctl_name       = VM_DROP_PAGECACHE,
1214                 .procname       = "drop_caches",
1215                 .data           = &sysctl_drop_caches,
1216                 .maxlen         = sizeof(int),
1217                 .mode           = 0644,
1218                 .proc_handler   = drop_caches_sysctl_handler,
1219                 .strategy       = &sysctl_intvec,
1220         },
1221         {
1222                 .ctl_name       = VM_MIN_FREE_KBYTES,
1223                 .procname       = "min_free_kbytes",
1224                 .data           = &min_free_kbytes,
1225                 .maxlen         = sizeof(min_free_kbytes),
1226                 .mode           = 0644,
1227                 .proc_handler   = &min_free_kbytes_sysctl_handler,
1228                 .strategy       = &sysctl_intvec,
1229                 .extra1         = &zero,
1230         },
1231         {
1232                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
1233                 .procname       = "percpu_pagelist_fraction",
1234                 .data           = &percpu_pagelist_fraction,
1235                 .maxlen         = sizeof(percpu_pagelist_fraction),
1236                 .mode           = 0644,
1237                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
1238                 .strategy       = &sysctl_intvec,
1239                 .extra1         = &min_percpu_pagelist_fract,
1240         },
1241 #ifdef CONFIG_MMU
1242         {
1243                 .ctl_name       = VM_MAX_MAP_COUNT,
1244                 .procname       = "max_map_count",
1245                 .data           = &sysctl_max_map_count,
1246                 .maxlen         = sizeof(sysctl_max_map_count),
1247                 .mode           = 0644,
1248                 .proc_handler   = &proc_dointvec
1249         },
1250 #else
1251         {
1252                 .ctl_name       = CTL_UNNUMBERED,
1253                 .procname       = "nr_trim_pages",
1254                 .data           = &sysctl_nr_trim_pages,
1255                 .maxlen         = sizeof(sysctl_nr_trim_pages),
1256                 .mode           = 0644,
1257                 .proc_handler   = &proc_dointvec_minmax,
1258                 .strategy       = &sysctl_intvec,
1259                 .extra1         = &zero,
1260         },
1261 #endif
1262         {
1263                 .ctl_name       = VM_LAPTOP_MODE,
1264                 .procname       = "laptop_mode",
1265                 .data           = &laptop_mode,
1266                 .maxlen         = sizeof(laptop_mode),
1267                 .mode           = 0644,
1268                 .proc_handler   = &proc_dointvec_jiffies,
1269                 .strategy       = &sysctl_jiffies,
1270         },
1271         {
1272                 .ctl_name       = VM_BLOCK_DUMP,
1273                 .procname       = "block_dump",
1274                 .data           = &block_dump,
1275                 .maxlen         = sizeof(block_dump),
1276                 .mode           = 0644,
1277                 .proc_handler   = &proc_dointvec,
1278                 .strategy       = &sysctl_intvec,
1279                 .extra1         = &zero,
1280         },
1281         {
1282                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
1283                 .procname       = "vfs_cache_pressure",
1284                 .data           = &sysctl_vfs_cache_pressure,
1285                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1286                 .mode           = 0644,
1287                 .proc_handler   = &proc_dointvec,
1288                 .strategy       = &sysctl_intvec,
1289                 .extra1         = &zero,
1290         },
1291 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1292         {
1293                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
1294                 .procname       = "legacy_va_layout",
1295                 .data           = &sysctl_legacy_va_layout,
1296                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1297                 .mode           = 0644,
1298                 .proc_handler   = &proc_dointvec,
1299                 .strategy       = &sysctl_intvec,
1300                 .extra1         = &zero,
1301         },
1302 #endif
1303 #ifdef CONFIG_NUMA
1304         {
1305                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
1306                 .procname       = "zone_reclaim_mode",
1307                 .data           = &zone_reclaim_mode,
1308                 .maxlen         = sizeof(zone_reclaim_mode),
1309                 .mode           = 0644,
1310                 .proc_handler   = &proc_dointvec,
1311                 .strategy       = &sysctl_intvec,
1312                 .extra1         = &zero,
1313         },
1314         {
1315                 .ctl_name       = VM_MIN_UNMAPPED,
1316                 .procname       = "min_unmapped_ratio",
1317                 .data           = &sysctl_min_unmapped_ratio,
1318                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1319                 .mode           = 0644,
1320                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1321                 .strategy       = &sysctl_intvec,
1322                 .extra1         = &zero,
1323                 .extra2         = &one_hundred,
1324         },
1325         {
1326                 .ctl_name       = VM_MIN_SLAB,
1327                 .procname       = "min_slab_ratio",
1328                 .data           = &sysctl_min_slab_ratio,
1329                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1330                 .mode           = 0644,
1331                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1332                 .strategy       = &sysctl_intvec,
1333                 .extra1         = &zero,
1334                 .extra2         = &one_hundred,
1335         },
1336 #endif
1337 #ifdef CONFIG_SMP
1338         {
1339                 .ctl_name       = CTL_UNNUMBERED,
1340                 .procname       = "stat_interval",
1341                 .data           = &sysctl_stat_interval,
1342                 .maxlen         = sizeof(sysctl_stat_interval),
1343                 .mode           = 0644,
1344                 .proc_handler   = &proc_dointvec_jiffies,
1345                 .strategy       = &sysctl_jiffies,
1346         },
1347 #endif
1348         {
1349                 .ctl_name       = CTL_UNNUMBERED,
1350                 .procname       = "mmap_min_addr",
1351                 .data           = &dac_mmap_min_addr,
1352                 .maxlen         = sizeof(unsigned long),
1353                 .mode           = 0644,
1354                 .proc_handler   = &mmap_min_addr_handler,
1355         },
1356 #ifdef CONFIG_NUMA
1357         {
1358                 .ctl_name       = CTL_UNNUMBERED,
1359                 .procname       = "numa_zonelist_order",
1360                 .data           = &numa_zonelist_order,
1361                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1362                 .mode           = 0644,
1363                 .proc_handler   = &numa_zonelist_order_handler,
1364                 .strategy       = &sysctl_string,
1365         },
1366 #endif
1367 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1368    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1369         {
1370                 .ctl_name       = VM_VDSO_ENABLED,
1371                 .procname       = "vdso_enabled",
1372                 .data           = &vdso_enabled,
1373                 .maxlen         = sizeof(vdso_enabled),
1374                 .mode           = 0644,
1375                 .proc_handler   = &proc_dointvec,
1376                 .strategy       = &sysctl_intvec,
1377                 .extra1         = &zero,
1378         },
1379 #endif
1380 #ifdef CONFIG_HIGHMEM
1381         {
1382                 .ctl_name       = CTL_UNNUMBERED,
1383                 .procname       = "highmem_is_dirtyable",
1384                 .data           = &vm_highmem_is_dirtyable,
1385                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1386                 .mode           = 0644,
1387                 .proc_handler   = &proc_dointvec_minmax,
1388                 .strategy       = &sysctl_intvec,
1389                 .extra1         = &zero,
1390                 .extra2         = &one,
1391         },
1392 #endif
1393         {
1394                 .ctl_name       = CTL_UNNUMBERED,
1395                 .procname       = "scan_unevictable_pages",
1396                 .data           = &scan_unevictable_pages,
1397                 .maxlen         = sizeof(scan_unevictable_pages),
1398                 .mode           = 0644,
1399                 .proc_handler   = &scan_unevictable_handler,
1400         },
1401 #ifdef CONFIG_MEMORY_FAILURE
1402         {
1403                 .ctl_name       = CTL_UNNUMBERED,
1404                 .procname       = "memory_failure_early_kill",
1405                 .data           = &sysctl_memory_failure_early_kill,
1406                 .maxlen         = sizeof(sysctl_memory_failure_early_kill),
1407                 .mode           = 0644,
1408                 .proc_handler   = &proc_dointvec_minmax,
1409                 .strategy       = &sysctl_intvec,
1410                 .extra1         = &zero,
1411                 .extra2         = &one,
1412         },
1413         {
1414                 .ctl_name       = CTL_UNNUMBERED,
1415                 .procname       = "memory_failure_recovery",
1416                 .data           = &sysctl_memory_failure_recovery,
1417                 .maxlen         = sizeof(sysctl_memory_failure_recovery),
1418                 .mode           = 0644,
1419                 .proc_handler   = &proc_dointvec_minmax,
1420                 .strategy       = &sysctl_intvec,
1421                 .extra1         = &zero,
1422                 .extra2         = &one,
1423         },
1424 #endif
1425
1426 /*
1427  * NOTE: do not add new entries to this table unless you have read
1428  * Documentation/sysctl/ctl_unnumbered.txt
1429  */
1430         { .ctl_name = 0 }
1431 };
1432
1433 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1434 static struct ctl_table binfmt_misc_table[] = {
1435         { .ctl_name = 0 }
1436 };
1437 #endif
1438
1439 static struct ctl_table fs_table[] = {
1440         {
1441                 .ctl_name       = FS_NRINODE,
1442                 .procname       = "inode-nr",
1443                 .data           = &inodes_stat,
1444                 .maxlen         = 2*sizeof(int),
1445                 .mode           = 0444,
1446                 .proc_handler   = &proc_dointvec,
1447         },
1448         {
1449                 .ctl_name       = FS_STATINODE,
1450                 .procname       = "inode-state",
1451                 .data           = &inodes_stat,
1452                 .maxlen         = 7*sizeof(int),
1453                 .mode           = 0444,
1454                 .proc_handler   = &proc_dointvec,
1455         },
1456         {
1457                 .procname       = "file-nr",
1458                 .data           = &files_stat,
1459                 .maxlen         = 3*sizeof(int),
1460                 .mode           = 0444,
1461                 .proc_handler   = &proc_nr_files,
1462         },
1463         {
1464                 .ctl_name       = FS_MAXFILE,
1465                 .procname       = "file-max",
1466                 .data           = &files_stat.max_files,
1467                 .maxlen         = sizeof(int),
1468                 .mode           = 0644,
1469                 .proc_handler   = &proc_dointvec,
1470         },
1471         {
1472                 .ctl_name       = CTL_UNNUMBERED,
1473                 .procname       = "nr_open",
1474                 .data           = &sysctl_nr_open,
1475                 .maxlen         = sizeof(int),
1476                 .mode           = 0644,
1477                 .proc_handler   = &proc_dointvec_minmax,
1478                 .extra1         = &sysctl_nr_open_min,
1479                 .extra2         = &sysctl_nr_open_max,
1480         },
1481         {
1482                 .ctl_name       = FS_DENTRY,
1483                 .procname       = "dentry-state",
1484                 .data           = &dentry_stat,
1485                 .maxlen         = 6*sizeof(int),
1486                 .mode           = 0444,
1487                 .proc_handler   = &proc_dointvec,
1488         },
1489         {
1490                 .ctl_name       = FS_OVERFLOWUID,
1491                 .procname       = "overflowuid",
1492                 .data           = &fs_overflowuid,
1493                 .maxlen         = sizeof(int),
1494                 .mode           = 0644,
1495                 .proc_handler   = &proc_dointvec_minmax,
1496                 .strategy       = &sysctl_intvec,
1497                 .extra1         = &minolduid,
1498                 .extra2         = &maxolduid,
1499         },
1500         {
1501                 .ctl_name       = FS_OVERFLOWGID,
1502                 .procname       = "overflowgid",
1503                 .data           = &fs_overflowgid,
1504                 .maxlen         = sizeof(int),
1505                 .mode           = 0644,
1506                 .proc_handler   = &proc_dointvec_minmax,
1507                 .strategy       = &sysctl_intvec,
1508                 .extra1         = &minolduid,
1509                 .extra2         = &maxolduid,
1510         },
1511 #ifdef CONFIG_FILE_LOCKING
1512         {
1513                 .ctl_name       = FS_LEASES,
1514                 .procname       = "leases-enable",
1515                 .data           = &leases_enable,
1516                 .maxlen         = sizeof(int),
1517                 .mode           = 0644,
1518                 .proc_handler   = &proc_dointvec,
1519         },
1520 #endif
1521 #ifdef CONFIG_DNOTIFY
1522         {
1523                 .ctl_name       = FS_DIR_NOTIFY,
1524                 .procname       = "dir-notify-enable",
1525                 .data           = &dir_notify_enable,
1526                 .maxlen         = sizeof(int),
1527                 .mode           = 0644,
1528                 .proc_handler   = &proc_dointvec,
1529         },
1530 #endif
1531 #ifdef CONFIG_MMU
1532 #ifdef CONFIG_FILE_LOCKING
1533         {
1534                 .ctl_name       = FS_LEASE_TIME,
1535                 .procname       = "lease-break-time",
1536                 .data           = &lease_break_time,
1537                 .maxlen         = sizeof(int),
1538                 .mode           = 0644,
1539                 .proc_handler   = &proc_dointvec,
1540         },
1541 #endif
1542 #ifdef CONFIG_AIO
1543         {
1544                 .procname       = "aio-nr",
1545                 .data           = &aio_nr,
1546                 .maxlen         = sizeof(aio_nr),
1547                 .mode           = 0444,
1548                 .proc_handler   = &proc_doulongvec_minmax,
1549         },
1550         {
1551                 .procname       = "aio-max-nr",
1552                 .data           = &aio_max_nr,
1553                 .maxlen         = sizeof(aio_max_nr),
1554                 .mode           = 0644,
1555                 .proc_handler   = &proc_doulongvec_minmax,
1556         },
1557 #endif /* CONFIG_AIO */
1558 #ifdef CONFIG_INOTIFY_USER
1559         {
1560                 .ctl_name       = FS_INOTIFY,
1561                 .procname       = "inotify",
1562                 .mode           = 0555,
1563                 .child          = inotify_table,
1564         },
1565 #endif
1566 #ifdef CONFIG_EPOLL
1567         {
1568                 .procname       = "epoll",
1569                 .mode           = 0555,
1570                 .child          = epoll_table,
1571         },
1572 #endif
1573 #endif
1574         {
1575                 .ctl_name       = KERN_SETUID_DUMPABLE,
1576                 .procname       = "suid_dumpable",
1577                 .data           = &suid_dumpable,
1578                 .maxlen         = sizeof(int),
1579                 .mode           = 0644,
1580                 .proc_handler   = &proc_dointvec_minmax,
1581                 .strategy       = &sysctl_intvec,
1582                 .extra1         = &zero,
1583                 .extra2         = &two,
1584         },
1585 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1586         {
1587                 .ctl_name       = CTL_UNNUMBERED,
1588                 .procname       = "binfmt_misc",
1589                 .mode           = 0555,
1590                 .child          = binfmt_misc_table,
1591         },
1592 #endif
1593 /*
1594  * NOTE: do not add new entries to this table unless you have read
1595  * Documentation/sysctl/ctl_unnumbered.txt
1596  */
1597         { .ctl_name = 0 }
1598 };
1599
1600 static struct ctl_table debug_table[] = {
1601 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1602         {
1603                 .ctl_name       = CTL_UNNUMBERED,
1604                 .procname       = "exception-trace",
1605                 .data           = &show_unhandled_signals,
1606                 .maxlen         = sizeof(int),
1607                 .mode           = 0644,
1608                 .proc_handler   = proc_dointvec
1609         },
1610 #endif
1611         { .ctl_name = 0 }
1612 };
1613
1614 static struct ctl_table dev_table[] = {
1615         { .ctl_name = 0 }
1616 };
1617
1618 static DEFINE_SPINLOCK(sysctl_lock);
1619
1620 /* called under sysctl_lock */
1621 static int use_table(struct ctl_table_header *p)
1622 {
1623         if (unlikely(p->unregistering))
1624                 return 0;
1625         p->used++;
1626         return 1;
1627 }
1628
1629 /* called under sysctl_lock */
1630 static void unuse_table(struct ctl_table_header *p)
1631 {
1632         if (!--p->used)
1633                 if (unlikely(p->unregistering))
1634                         complete(p->unregistering);
1635 }
1636
1637 /* called under sysctl_lock, will reacquire if has to wait */
1638 static void start_unregistering(struct ctl_table_header *p)
1639 {
1640         /*
1641          * if p->used is 0, nobody will ever touch that entry again;
1642          * we'll eliminate all paths to it before dropping sysctl_lock
1643          */
1644         if (unlikely(p->used)) {
1645                 struct completion wait;
1646                 init_completion(&wait);
1647                 p->unregistering = &wait;
1648                 spin_unlock(&sysctl_lock);
1649                 wait_for_completion(&wait);
1650                 spin_lock(&sysctl_lock);
1651         } else {
1652                 /* anything non-NULL; we'll never dereference it */
1653                 p->unregistering = ERR_PTR(-EINVAL);
1654         }
1655         /*
1656          * do not remove from the list until nobody holds it; walking the
1657          * list in do_sysctl() relies on that.
1658          */
1659         list_del_init(&p->ctl_entry);
1660 }
1661
1662 void sysctl_head_get(struct ctl_table_header *head)
1663 {
1664         spin_lock(&sysctl_lock);
1665         head->count++;
1666         spin_unlock(&sysctl_lock);
1667 }
1668
1669 void sysctl_head_put(struct ctl_table_header *head)
1670 {
1671         spin_lock(&sysctl_lock);
1672         if (!--head->count)
1673                 kfree(head);
1674         spin_unlock(&sysctl_lock);
1675 }
1676
1677 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1678 {
1679         if (!head)
1680                 BUG();
1681         spin_lock(&sysctl_lock);
1682         if (!use_table(head))
1683                 head = ERR_PTR(-ENOENT);
1684         spin_unlock(&sysctl_lock);
1685         return head;
1686 }
1687
1688 void sysctl_head_finish(struct ctl_table_header *head)
1689 {
1690         if (!head)
1691                 return;
1692         spin_lock(&sysctl_lock);
1693         unuse_table(head);
1694         spin_unlock(&sysctl_lock);
1695 }
1696
1697 static struct ctl_table_set *
1698 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1699 {
1700         struct ctl_table_set *set = &root->default_set;
1701         if (root->lookup)
1702                 set = root->lookup(root, namespaces);
1703         return set;
1704 }
1705
1706 static struct list_head *
1707 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1708 {
1709         struct ctl_table_set *set = lookup_header_set(root, namespaces);
1710         return &set->list;
1711 }
1712
1713 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1714                                             struct ctl_table_header *prev)
1715 {
1716         struct ctl_table_root *root;
1717         struct list_head *header_list;
1718         struct ctl_table_header *head;
1719         struct list_head *tmp;
1720
1721         spin_lock(&sysctl_lock);
1722         if (prev) {
1723                 head = prev;
1724                 tmp = &prev->ctl_entry;
1725                 unuse_table(prev);
1726                 goto next;
1727         }
1728         tmp = &root_table_header.ctl_entry;
1729         for (;;) {
1730                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1731
1732                 if (!use_table(head))
1733                         goto next;
1734                 spin_unlock(&sysctl_lock);
1735                 return head;
1736         next:
1737                 root = head->root;
1738                 tmp = tmp->next;
1739                 header_list = lookup_header_list(root, namespaces);
1740                 if (tmp != header_list)
1741                         continue;
1742
1743                 do {
1744                         root = list_entry(root->root_list.next,
1745                                         struct ctl_table_root, root_list);
1746                         if (root == &sysctl_table_root)
1747                                 goto out;
1748                         header_list = lookup_header_list(root, namespaces);
1749                 } while (list_empty(header_list));
1750                 tmp = header_list->next;
1751         }
1752 out:
1753         spin_unlock(&sysctl_lock);
1754         return NULL;
1755 }
1756
1757 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1758 {
1759         return __sysctl_head_next(current->nsproxy, prev);
1760 }
1761
1762 void register_sysctl_root(struct ctl_table_root *root)
1763 {
1764         spin_lock(&sysctl_lock);
1765         list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1766         spin_unlock(&sysctl_lock);
1767 }
1768
1769 #ifdef CONFIG_SYSCTL_SYSCALL
1770 /* Perform the actual read/write of a sysctl table entry. */
1771 static int do_sysctl_strategy(struct ctl_table_root *root,
1772                         struct ctl_table *table,
1773                         void __user *oldval, size_t __user *oldlenp,
1774                         void __user *newval, size_t newlen)
1775 {
1776         int op = 0, rc;
1777
1778         if (oldval)
1779                 op |= MAY_READ;
1780         if (newval)
1781                 op |= MAY_WRITE;
1782         if (sysctl_perm(root, table, op))
1783                 return -EPERM;
1784
1785         if (table->strategy) {
1786                 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1787                 if (rc < 0)
1788                         return rc;
1789                 if (rc > 0)
1790                         return 0;
1791         }
1792
1793         /* If there is no strategy routine, or if the strategy returns
1794          * zero, proceed with automatic r/w */
1795         if (table->data && table->maxlen) {
1796                 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1797                 if (rc < 0)
1798                         return rc;
1799         }
1800         return 0;
1801 }
1802
1803 static int parse_table(int __user *name, int nlen,
1804                        void __user *oldval, size_t __user *oldlenp,
1805                        void __user *newval, size_t newlen,
1806                        struct ctl_table_root *root,
1807                        struct ctl_table *table)
1808 {
1809         int n;
1810 repeat:
1811         if (!nlen)
1812                 return -ENOTDIR;
1813         if (get_user(n, name))
1814                 return -EFAULT;
1815         for ( ; table->ctl_name || table->procname; table++) {
1816                 if (!table->ctl_name)
1817                         continue;
1818                 if (n == table->ctl_name) {
1819                         int error;
1820                         if (table->child) {
1821                                 if (sysctl_perm(root, table, MAY_EXEC))
1822                                         return -EPERM;
1823                                 name++;
1824                                 nlen--;
1825                                 table = table->child;
1826                                 goto repeat;
1827                         }
1828                         error = do_sysctl_strategy(root, table,
1829                                                    oldval, oldlenp,
1830                                                    newval, newlen);
1831                         return error;
1832                 }
1833         }
1834         return -ENOTDIR;
1835 }
1836
1837 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1838                void __user *newval, size_t newlen)
1839 {
1840         struct ctl_table_header *head;
1841         int error = -ENOTDIR;
1842
1843         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1844                 return -ENOTDIR;
1845         if (oldval) {
1846                 int old_len;
1847                 if (!oldlenp || get_user(old_len, oldlenp))
1848                         return -EFAULT;
1849         }
1850
1851         for (head = sysctl_head_next(NULL); head;
1852                         head = sysctl_head_next(head)) {
1853                 error = parse_table(name, nlen, oldval, oldlenp,
1854                                         newval, newlen,
1855                                         head->root, head->ctl_table);
1856                 if (error != -ENOTDIR) {
1857                         sysctl_head_finish(head);
1858                         break;
1859                 }
1860         }
1861         return error;
1862 }
1863
1864 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1865 {
1866         struct __sysctl_args tmp;
1867         int error;
1868
1869         if (copy_from_user(&tmp, args, sizeof(tmp)))
1870                 return -EFAULT;
1871
1872         error = deprecated_sysctl_warning(&tmp);
1873         if (error)
1874                 goto out;
1875
1876         lock_kernel();
1877         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1878                           tmp.newval, tmp.newlen);
1879         unlock_kernel();
1880 out:
1881         return error;
1882 }
1883 #endif /* CONFIG_SYSCTL_SYSCALL */
1884
1885 /*
1886  * sysctl_perm does NOT grant the superuser all rights automatically, because
1887  * some sysctl variables are readonly even to root.
1888  */
1889
1890 static int test_perm(int mode, int op)
1891 {
1892         if (!current_euid())
1893                 mode >>= 6;
1894         else if (in_egroup_p(0))
1895                 mode >>= 3;
1896         if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1897                 return 0;
1898         return -EACCES;
1899 }
1900
1901 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1902 {
1903         int error;
1904         int mode;
1905
1906         error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1907         if (error)
1908                 return error;
1909
1910         if (root->permissions)
1911                 mode = root->permissions(root, current->nsproxy, table);
1912         else
1913                 mode = table->mode;
1914
1915         return test_perm(mode, op);
1916 }
1917
1918 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1919 {
1920         for (; table->ctl_name || table->procname; table++) {
1921                 table->parent = parent;
1922                 if (table->child)
1923                         sysctl_set_parent(table, table->child);
1924         }
1925 }
1926
1927 static __init int sysctl_init(void)
1928 {
1929         sysctl_set_parent(NULL, root_table);
1930 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1931         {
1932                 int err;
1933                 err = sysctl_check_table(current->nsproxy, root_table);
1934         }
1935 #endif
1936         return 0;
1937 }
1938
1939 core_initcall(sysctl_init);
1940
1941 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1942                                       struct ctl_table *table)
1943 {
1944         struct ctl_table *p;
1945         const char *s = branch->procname;
1946
1947         /* branch should have named subdirectory as its first element */
1948         if (!s || !branch->child)
1949                 return NULL;
1950
1951         /* ... and nothing else */
1952         if (branch[1].procname || branch[1].ctl_name)
1953                 return NULL;
1954
1955         /* table should contain subdirectory with the same name */
1956         for (p = table; p->procname || p->ctl_name; p++) {
1957                 if (!p->child)
1958                         continue;
1959                 if (p->procname && strcmp(p->procname, s) == 0)
1960                         return p;
1961         }
1962         return NULL;
1963 }
1964
1965 /* see if attaching q to p would be an improvement */
1966 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1967 {
1968         struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1969         struct ctl_table *next;
1970         int is_better = 0;
1971         int not_in_parent = !p->attached_by;
1972
1973         while ((next = is_branch_in(by, to)) != NULL) {
1974                 if (by == q->attached_by)
1975                         is_better = 1;
1976                 if (to == p->attached_by)
1977                         not_in_parent = 1;
1978                 by = by->child;
1979                 to = next->child;
1980         }
1981
1982         if (is_better && not_in_parent) {
1983                 q->attached_by = by;
1984                 q->attached_to = to;
1985                 q->parent = p;
1986         }
1987 }
1988
1989 /**
1990  * __register_sysctl_paths - register a sysctl hierarchy
1991  * @root: List of sysctl headers to register on
1992  * @namespaces: Data to compute which lists of sysctl entries are visible
1993  * @path: The path to the directory the sysctl table is in.
1994  * @table: the top-level table structure
1995  *
1996  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1997  * array. A completely 0 filled entry terminates the table.
1998  *
1999  * The members of the &struct ctl_table structure are used as follows:
2000  *
2001  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
2002  *            must be unique within that level of sysctl
2003  *
2004  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
2005  *            enter a sysctl file
2006  *
2007  * data - a pointer to data for use by proc_handler
2008  *
2009  * maxlen - the maximum size in bytes of the data
2010  *
2011  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
2012  *
2013  * child - a pointer to the child sysctl table if this entry is a directory, or
2014  *         %NULL.
2015  *
2016  * proc_handler - the text handler routine (described below)
2017  *
2018  * strategy - the strategy routine (described below)
2019  *
2020  * de - for internal use by the sysctl routines
2021  *
2022  * extra1, extra2 - extra pointers usable by the proc handler routines
2023  *
2024  * Leaf nodes in the sysctl tree will be represented by a single file
2025  * under /proc; non-leaf nodes will be represented by directories.
2026  *
2027  * sysctl(2) can automatically manage read and write requests through
2028  * the sysctl table.  The data and maxlen fields of the ctl_table
2029  * struct enable minimal validation of the values being written to be
2030  * performed, and the mode field allows minimal authentication.
2031  *
2032  * More sophisticated management can be enabled by the provision of a
2033  * strategy routine with the table entry.  This will be called before
2034  * any automatic read or write of the data is performed.
2035  *
2036  * The strategy routine may return
2037  *
2038  * < 0 - Error occurred (error is passed to user process)
2039  *
2040  * 0   - OK - proceed with automatic read or write.
2041  *
2042  * > 0 - OK - read or write has been done by the strategy routine, so
2043  *       return immediately.
2044  *
2045  * There must be a proc_handler routine for any terminal nodes
2046  * mirrored under /proc/sys (non-terminals are handled by a built-in
2047  * directory handler).  Several default handlers are available to
2048  * cover common cases -
2049  *
2050  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
2051  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
2052  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
2053  *
2054  * It is the handler's job to read the input buffer from user memory
2055  * and process it. The handler should return 0 on success.
2056  *
2057  * This routine returns %NULL on a failure to register, and a pointer
2058  * to the table header on success.
2059  */
2060 struct ctl_table_header *__register_sysctl_paths(
2061         struct ctl_table_root *root,
2062         struct nsproxy *namespaces,
2063         const struct ctl_path *path, struct ctl_table *table)
2064 {
2065         struct ctl_table_header *header;
2066         struct ctl_table *new, **prevp;
2067         unsigned int n, npath;
2068         struct ctl_table_set *set;
2069
2070         /* Count the path components */
2071         for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
2072                 ;
2073
2074         /*
2075          * For each path component, allocate a 2-element ctl_table array.
2076          * The first array element will be filled with the sysctl entry
2077          * for this, the second will be the sentinel (ctl_name == 0).
2078          *
2079          * We allocate everything in one go so that we don't have to
2080          * worry about freeing additional memory in unregister_sysctl_table.
2081          */
2082         header = kzalloc(sizeof(struct ctl_table_header) +
2083                          (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
2084         if (!header)
2085                 return NULL;
2086
2087         new = (struct ctl_table *) (header + 1);
2088
2089         /* Now connect the dots */
2090         prevp = &header->ctl_table;
2091         for (n = 0; n < npath; ++n, ++path) {
2092                 /* Copy the procname */
2093                 new->procname = path->procname;
2094                 new->ctl_name = path->ctl_name;
2095                 new->mode     = 0555;
2096
2097                 *prevp = new;
2098                 prevp = &new->child;
2099
2100                 new += 2;
2101         }
2102         *prevp = table;
2103         header->ctl_table_arg = table;
2104
2105         INIT_LIST_HEAD(&header->ctl_entry);
2106         header->used = 0;
2107         header->unregistering = NULL;
2108         header->root = root;
2109         sysctl_set_parent(NULL, header->ctl_table);
2110         header->count = 1;
2111 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2112         if (sysctl_check_table(namespaces, header->ctl_table)) {
2113                 kfree(header);
2114                 return NULL;
2115         }
2116 #endif
2117         spin_lock(&sysctl_lock);
2118         header->set = lookup_header_set(root, namespaces);
2119         header->attached_by = header->ctl_table;
2120         header->attached_to = root_table;
2121         header->parent = &root_table_header;
2122         for (set = header->set; set; set = set->parent) {
2123                 struct ctl_table_header *p;
2124                 list_for_each_entry(p, &set->list, ctl_entry) {
2125                         if (p->unregistering)
2126                                 continue;
2127                         try_attach(p, header);
2128                 }
2129         }
2130         header->parent->count++;
2131         list_add_tail(&header->ctl_entry, &header->set->list);
2132         spin_unlock(&sysctl_lock);
2133
2134         return header;
2135 }
2136
2137 /**
2138  * register_sysctl_table_path - register a sysctl table hierarchy
2139  * @path: The path to the directory the sysctl table is in.
2140  * @table: the top-level table structure
2141  *
2142  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2143  * array. A completely 0 filled entry terminates the table.
2144  *
2145  * See __register_sysctl_paths for more details.
2146  */
2147 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2148                                                 struct ctl_table *table)
2149 {
2150         return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2151                                         path, table);
2152 }
2153
2154 /**
2155  * register_sysctl_table - register a sysctl table hierarchy
2156  * @table: the top-level table structure
2157  *
2158  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2159  * array. A completely 0 filled entry terminates the table.
2160  *
2161  * See register_sysctl_paths for more details.
2162  */
2163 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2164 {
2165         static const struct ctl_path null_path[] = { {} };
2166
2167         return register_sysctl_paths(null_path, table);
2168 }
2169
2170 /**
2171  * unregister_sysctl_table - unregister a sysctl table hierarchy
2172  * @header: the header returned from register_sysctl_table
2173  *
2174  * Unregisters the sysctl table and all children. proc entries may not
2175  * actually be removed until they are no longer used by anyone.
2176  */
2177 void unregister_sysctl_table(struct ctl_table_header * header)
2178 {
2179         might_sleep();
2180
2181         if (header == NULL)
2182                 return;
2183
2184         spin_lock(&sysctl_lock);
2185         start_unregistering(header);
2186         if (!--header->parent->count) {
2187                 WARN_ON(1);
2188                 kfree(header->parent);
2189         }
2190         if (!--header->count)
2191                 kfree(header);
2192         spin_unlock(&sysctl_lock);
2193 }
2194
2195 int sysctl_is_seen(struct ctl_table_header *p)
2196 {
2197         struct ctl_table_set *set = p->set;
2198         int res;
2199         spin_lock(&sysctl_lock);
2200         if (p->unregistering)
2201                 res = 0;
2202         else if (!set->is_seen)
2203                 res = 1;
2204         else
2205                 res = set->is_seen(set);
2206         spin_unlock(&sysctl_lock);
2207         return res;
2208 }
2209
2210 void setup_sysctl_set(struct ctl_table_set *p,
2211         struct ctl_table_set *parent,
2212         int (*is_seen)(struct ctl_table_set *))
2213 {
2214         INIT_LIST_HEAD(&p->list);
2215         p->parent = parent ? parent : &sysctl_table_root.default_set;
2216         p->is_seen = is_seen;
2217 }
2218
2219 #else /* !CONFIG_SYSCTL */
2220 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2221 {
2222         return NULL;
2223 }
2224
2225 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2226                                                     struct ctl_table *table)
2227 {
2228         return NULL;
2229 }
2230
2231 void unregister_sysctl_table(struct ctl_table_header * table)
2232 {
2233 }
2234
2235 void setup_sysctl_set(struct ctl_table_set *p,
2236         struct ctl_table_set *parent,
2237         int (*is_seen)(struct ctl_table_set *))
2238 {
2239 }
2240
2241 void sysctl_head_put(struct ctl_table_header *head)
2242 {
2243 }
2244
2245 #endif /* CONFIG_SYSCTL */
2246
2247 /*
2248  * /proc/sys support
2249  */
2250
2251 #ifdef CONFIG_PROC_SYSCTL
2252
2253 static int _proc_do_string(void* data, int maxlen, int write,
2254                            void __user *buffer,
2255                            size_t *lenp, loff_t *ppos)
2256 {
2257         size_t len;
2258         char __user *p;
2259         char c;
2260
2261         if (!data || !maxlen || !*lenp) {
2262                 *lenp = 0;
2263                 return 0;
2264         }
2265
2266         if (write) {
2267                 len = 0;
2268                 p = buffer;
2269                 while (len < *lenp) {
2270                         if (get_user(c, p++))
2271                                 return -EFAULT;
2272                         if (c == 0 || c == '\n')
2273                                 break;
2274                         len++;
2275                 }
2276                 if (len >= maxlen)
2277                         len = maxlen-1;
2278                 if(copy_from_user(data, buffer, len))
2279                         return -EFAULT;
2280                 ((char *) data)[len] = 0;
2281                 *ppos += *lenp;
2282         } else {
2283                 len = strlen(data);
2284                 if (len > maxlen)
2285                         len = maxlen;
2286
2287                 if (*ppos > len) {
2288                         *lenp = 0;
2289                         return 0;
2290                 }
2291
2292                 data += *ppos;
2293                 len  -= *ppos;
2294
2295                 if (len > *lenp)
2296                         len = *lenp;
2297                 if (len)
2298                         if(copy_to_user(buffer, data, len))
2299                                 return -EFAULT;
2300                 if (len < *lenp) {
2301                         if(put_user('\n', ((char __user *) buffer) + len))
2302                                 return -EFAULT;
2303                         len++;
2304                 }
2305                 *lenp = len;
2306                 *ppos += len;
2307         }
2308         return 0;
2309 }
2310
2311 /**
2312  * proc_dostring - read a string sysctl
2313  * @table: the sysctl table
2314  * @write: %TRUE if this is a write to the sysctl file
2315  * @buffer: the user buffer
2316  * @lenp: the size of the user buffer
2317  * @ppos: file position
2318  *
2319  * Reads/writes a string from/to the user buffer. If the kernel
2320  * buffer provided is not large enough to hold the string, the
2321  * string is truncated. The copied string is %NULL-terminated.
2322  * If the string is being read by the user process, it is copied
2323  * and a newline '\n' is added. It is truncated if the buffer is
2324  * not large enough.
2325  *
2326  * Returns 0 on success.
2327  */
2328 int proc_dostring(struct ctl_table *table, int write,
2329                   void __user *buffer, size_t *lenp, loff_t *ppos)
2330 {
2331         return _proc_do_string(table->data, table->maxlen, write,
2332                                buffer, lenp, ppos);
2333 }
2334
2335
2336 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2337                                  int *valp,
2338                                  int write, void *data)
2339 {
2340         if (write) {
2341                 *valp = *negp ? -*lvalp : *lvalp;
2342         } else {
2343                 int val = *valp;
2344                 if (val < 0) {
2345                         *negp = -1;
2346                         *lvalp = (unsigned long)-val;
2347                 } else {
2348                         *negp = 0;
2349                         *lvalp = (unsigned long)val;
2350                 }
2351         }
2352         return 0;
2353 }
2354
2355 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2356                   int write, void __user *buffer,
2357                   size_t *lenp, loff_t *ppos,
2358                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2359                               int write, void *data),
2360                   void *data)
2361 {
2362 #define TMPBUFLEN 21
2363         int *i, vleft, first = 1, neg;
2364         unsigned long lval;
2365         size_t left, len;
2366
2367         char buf[TMPBUFLEN], *p;
2368         char __user *s = buffer;
2369
2370         if (!tbl_data || !table->maxlen || !*lenp ||
2371             (*ppos && !write)) {
2372                 *lenp = 0;
2373                 return 0;
2374         }
2375
2376         i = (int *) tbl_data;
2377         vleft = table->maxlen / sizeof(*i);
2378         left = *lenp;
2379
2380         if (!conv)
2381                 conv = do_proc_dointvec_conv;
2382
2383         for (; left && vleft--; i++, first=0) {
2384                 if (write) {
2385                         while (left) {
2386                                 char c;
2387                                 if (get_user(c, s))
2388                                         return -EFAULT;
2389                                 if (!isspace(c))
2390                                         break;
2391                                 left--;
2392                                 s++;
2393                         }
2394                         if (!left)
2395                                 break;
2396                         neg = 0;
2397                         len = left;
2398                         if (len > sizeof(buf) - 1)
2399                                 len = sizeof(buf) - 1;
2400                         if (copy_from_user(buf, s, len))
2401                                 return -EFAULT;
2402                         buf[len] = 0;
2403                         p = buf;
2404                         if (*p == '-' && left > 1) {
2405                                 neg = 1;
2406                                 p++;
2407                         }
2408                         if (*p < '0' || *p > '9')
2409                                 break;
2410
2411                         lval = simple_strtoul(p, &p, 0);
2412
2413                         len = p-buf;
2414                         if ((len < left) && *p && !isspace(*p))
2415                                 break;
2416                         s += len;
2417                         left -= len;
2418
2419                         if (conv(&neg, &lval, i, 1, data))
2420                                 break;
2421                 } else {
2422                         p = buf;
2423                         if (!first)
2424                                 *p++ = '\t';
2425
2426                         if (conv(&neg, &lval, i, 0, data))
2427                                 break;
2428
2429                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
2430                         len = strlen(buf);
2431                         if (len > left)
2432                                 len = left;
2433                         if(copy_to_user(s, buf, len))
2434                                 return -EFAULT;
2435                         left -= len;
2436                         s += len;
2437                 }
2438         }
2439
2440         if (!write && !first && left) {
2441                 if(put_user('\n', s))
2442                         return -EFAULT;
2443                 left--, s++;
2444         }
2445         if (write) {
2446                 while (left) {
2447                         char c;
2448                         if (get_user(c, s++))
2449                                 return -EFAULT;
2450                         if (!isspace(c))
2451                                 break;
2452                         left--;
2453                 }
2454         }
2455         if (write && first)
2456                 return -EINVAL;
2457         *lenp -= left;
2458         *ppos += *lenp;
2459         return 0;
2460 #undef TMPBUFLEN
2461 }
2462
2463 static int do_proc_dointvec(struct ctl_table *table, int write,
2464                   void __user *buffer, size_t *lenp, loff_t *ppos,
2465                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2466                               int write, void *data),
2467                   void *data)
2468 {
2469         return __do_proc_dointvec(table->data, table, write,
2470                         buffer, lenp, ppos, conv, data);
2471 }
2472
2473 /**
2474  * proc_dointvec - read a vector of integers
2475  * @table: the sysctl table
2476  * @write: %TRUE if this is a write to the sysctl file
2477  * @buffer: the user buffer
2478  * @lenp: the size of the user buffer
2479  * @ppos: file position
2480  *
2481  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2482  * values from/to the user buffer, treated as an ASCII string.
2483  *
2484  * Returns 0 on success.
2485  */
2486 int proc_dointvec(struct ctl_table *table, int write,
2487                      void __user *buffer, size_t *lenp, loff_t *ppos)
2488 {
2489     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2490                             NULL,NULL);
2491 }
2492
2493 /*
2494  * Taint values can only be increased
2495  * This means we can safely use a temporary.
2496  */
2497 static int proc_taint(struct ctl_table *table, int write,
2498                                void __user *buffer, size_t *lenp, loff_t *ppos)
2499 {
2500         struct ctl_table t;
2501         unsigned long tmptaint = get_taint();
2502         int err;
2503
2504         if (write && !capable(CAP_SYS_ADMIN))
2505                 return -EPERM;
2506
2507         t = *table;
2508         t.data = &tmptaint;
2509         err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2510         if (err < 0)
2511                 return err;
2512
2513         if (write) {
2514                 /*
2515                  * Poor man's atomic or. Not worth adding a primitive
2516                  * to everyone's atomic.h for this
2517                  */
2518                 int i;
2519                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2520                         if ((tmptaint >> i) & 1)
2521                                 add_taint(i);
2522                 }
2523         }
2524
2525         return err;
2526 }
2527
2528 struct do_proc_dointvec_minmax_conv_param {
2529         int *min;
2530         int *max;
2531 };
2532
2533 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2534                                         int *valp,
2535                                         int write, void *data)
2536 {
2537         struct do_proc_dointvec_minmax_conv_param *param = data;
2538         if (write) {
2539                 int val = *negp ? -*lvalp : *lvalp;
2540                 if ((param->min && *param->min > val) ||
2541                     (param->max && *param->max < val))
2542                         return -EINVAL;
2543                 *valp = val;
2544         } else {
2545                 int val = *valp;
2546                 if (val < 0) {
2547                         *negp = -1;
2548                         *lvalp = (unsigned long)-val;
2549                 } else {
2550                         *negp = 0;
2551                         *lvalp = (unsigned long)val;
2552                 }
2553         }
2554         return 0;
2555 }
2556
2557 /**
2558  * proc_dointvec_minmax - read a vector of integers with min/max values
2559  * @table: the sysctl table
2560  * @write: %TRUE if this is a write to the sysctl file
2561  * @buffer: the user buffer
2562  * @lenp: the size of the user buffer
2563  * @ppos: file position
2564  *
2565  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2566  * values from/to the user buffer, treated as an ASCII string.
2567  *
2568  * This routine will ensure the values are within the range specified by
2569  * table->extra1 (min) and table->extra2 (max).
2570  *
2571  * Returns 0 on success.
2572  */
2573 int proc_dointvec_minmax(struct ctl_table *table, int write,
2574                   void __user *buffer, size_t *lenp, loff_t *ppos)
2575 {
2576         struct do_proc_dointvec_minmax_conv_param param = {
2577                 .min = (int *) table->extra1,
2578                 .max = (int *) table->extra2,
2579         };
2580         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2581                                 do_proc_dointvec_minmax_conv, &param);
2582 }
2583
2584 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2585                                      void __user *buffer,
2586                                      size_t *lenp, loff_t *ppos,
2587                                      unsigned long convmul,
2588                                      unsigned long convdiv)
2589 {
2590 #define TMPBUFLEN 21
2591         unsigned long *i, *min, *max, val;
2592         int vleft, first=1, neg;
2593         size_t len, left;
2594         char buf[TMPBUFLEN], *p;
2595         char __user *s = buffer;
2596
2597         if (!data || !table->maxlen || !*lenp ||
2598             (*ppos && !write)) {
2599                 *lenp = 0;
2600                 return 0;
2601         }
2602
2603         i = (unsigned long *) data;
2604         min = (unsigned long *) table->extra1;
2605         max = (unsigned long *) table->extra2;
2606         vleft = table->maxlen / sizeof(unsigned long);
2607         left = *lenp;
2608
2609         for (; left && vleft--; i++, min++, max++, first=0) {
2610                 if (write) {
2611                         while (left) {
2612                                 char c;
2613                                 if (get_user(c, s))
2614                                         return -EFAULT;
2615                                 if (!isspace(c))
2616                                         break;
2617                                 left--;
2618                                 s++;
2619                         }
2620                         if (!left)
2621                                 break;
2622                         neg = 0;
2623                         len = left;
2624                         if (len > TMPBUFLEN-1)
2625                                 len = TMPBUFLEN-1;
2626                         if (copy_from_user(buf, s, len))
2627                                 return -EFAULT;
2628                         buf[len] = 0;
2629                         p = buf;
2630                         if (*p == '-' && left > 1) {
2631                                 neg = 1;
2632                                 p++;
2633                         }
2634                         if (*p < '0' || *p > '9')
2635                                 break;
2636                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2637                         len = p-buf;
2638                         if ((len < left) && *p && !isspace(*p))
2639                                 break;
2640                         if (neg)
2641                                 val = -val;
2642                         s += len;
2643                         left -= len;
2644
2645                         if(neg)
2646                                 continue;
2647                         if ((min && val < *min) || (max && val > *max))
2648                                 continue;
2649                         *i = val;
2650                 } else {
2651                         p = buf;
2652                         if (!first)
2653                                 *p++ = '\t';
2654                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2655                         len = strlen(buf);
2656                         if (len > left)
2657                                 len = left;
2658                         if(copy_to_user(s, buf, len))
2659                                 return -EFAULT;
2660                         left -= len;
2661                         s += len;
2662                 }
2663         }
2664
2665         if (!write && !first && left) {
2666                 if(put_user('\n', s))
2667                         return -EFAULT;
2668                 left--, s++;
2669         }
2670         if (write) {
2671                 while (left) {
2672                         char c;
2673                         if (get_user(c, s++))
2674                                 return -EFAULT;
2675                         if (!isspace(c))
2676                                 break;
2677                         left--;
2678                 }
2679         }
2680         if (write && first)
2681                 return -EINVAL;
2682         *lenp -= left;
2683         *ppos += *lenp;
2684         return 0;
2685 #undef TMPBUFLEN
2686 }
2687
2688 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2689                                      void __user *buffer,
2690                                      size_t *lenp, loff_t *ppos,
2691                                      unsigned long convmul,
2692                                      unsigned long convdiv)
2693 {
2694         return __do_proc_doulongvec_minmax(table->data, table, write,
2695                         buffer, lenp, ppos, convmul, convdiv);
2696 }
2697
2698 /**
2699  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2700  * @table: the sysctl table
2701  * @write: %TRUE if this is a write to the sysctl file
2702  * @buffer: the user buffer
2703  * @lenp: the size of the user buffer
2704  * @ppos: file position
2705  *
2706  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2707  * values from/to the user buffer, treated as an ASCII string.
2708  *
2709  * This routine will ensure the values are within the range specified by
2710  * table->extra1 (min) and table->extra2 (max).
2711  *
2712  * Returns 0 on success.
2713  */
2714 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2715                            void __user *buffer, size_t *lenp, loff_t *ppos)
2716 {
2717     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2718 }
2719
2720 /**
2721  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2722  * @table: the sysctl table
2723  * @write: %TRUE if this is a write to the sysctl file
2724  * @buffer: the user buffer
2725  * @lenp: the size of the user buffer
2726  * @ppos: file position
2727  *
2728  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2729  * values from/to the user buffer, treated as an ASCII string. The values
2730  * are treated as milliseconds, and converted to jiffies when they are stored.
2731  *
2732  * This routine will ensure the values are within the range specified by
2733  * table->extra1 (min) and table->extra2 (max).
2734  *
2735  * Returns 0 on success.
2736  */
2737 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2738                                       void __user *buffer,
2739                                       size_t *lenp, loff_t *ppos)
2740 {
2741     return do_proc_doulongvec_minmax(table, write, buffer,
2742                                      lenp, ppos, HZ, 1000l);
2743 }
2744
2745
2746 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2747                                          int *valp,
2748                                          int write, void *data)
2749 {
2750         if (write) {
2751                 if (*lvalp > LONG_MAX / HZ)
2752                         return 1;
2753                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2754         } else {
2755                 int val = *valp;
2756                 unsigned long lval;
2757                 if (val < 0) {
2758                         *negp = -1;
2759                         lval = (unsigned long)-val;
2760                 } else {
2761                         *negp = 0;
2762                         lval = (unsigned long)val;
2763                 }
2764                 *lvalp = lval / HZ;
2765         }
2766         return 0;
2767 }
2768
2769 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2770                                                 int *valp,
2771                                                 int write, void *data)
2772 {
2773         if (write) {
2774                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2775                         return 1;
2776                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2777         } else {
2778                 int val = *valp;
2779                 unsigned long lval;
2780                 if (val < 0) {
2781                         *negp = -1;
2782                         lval = (unsigned long)-val;
2783                 } else {
2784                         *negp = 0;
2785                         lval = (unsigned long)val;
2786                 }
2787                 *lvalp = jiffies_to_clock_t(lval);
2788         }
2789         return 0;
2790 }
2791
2792 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2793                                             int *valp,
2794                                             int write, void *data)
2795 {
2796         if (write) {
2797                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2798         } else {
2799                 int val = *valp;
2800                 unsigned long lval;
2801                 if (val < 0) {
2802                         *negp = -1;
2803                         lval = (unsigned long)-val;
2804                 } else {
2805                         *negp = 0;
2806                         lval = (unsigned long)val;
2807                 }
2808                 *lvalp = jiffies_to_msecs(lval);
2809         }
2810         return 0;
2811 }
2812
2813 /**
2814  * proc_dointvec_jiffies - read a vector of integers as seconds
2815  * @table: the sysctl table
2816  * @write: %TRUE if this is a write to the sysctl file
2817  * @buffer: the user buffer
2818  * @lenp: the size of the user buffer
2819  * @ppos: file position
2820  *
2821  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2822  * values from/to the user buffer, treated as an ASCII string.
2823  * The values read are assumed to be in seconds, and are converted into
2824  * jiffies.
2825  *
2826  * Returns 0 on success.
2827  */
2828 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2829                           void __user *buffer, size_t *lenp, loff_t *ppos)
2830 {
2831     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2832                             do_proc_dointvec_jiffies_conv,NULL);
2833 }
2834
2835 /**
2836  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2837  * @table: the sysctl table
2838  * @write: %TRUE if this is a write to the sysctl file
2839  * @buffer: the user buffer
2840  * @lenp: the size of the user buffer
2841  * @ppos: pointer to the file position
2842  *
2843  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2844  * values from/to the user buffer, treated as an ASCII string.
2845  * The values read are assumed to be in 1/USER_HZ seconds, and
2846  * are converted into jiffies.
2847  *
2848  * Returns 0 on success.
2849  */
2850 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2851                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2852 {
2853     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2854                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2855 }
2856
2857 /**
2858  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2859  * @table: the sysctl table
2860  * @write: %TRUE if this is a write to the sysctl file
2861  * @buffer: the user buffer
2862  * @lenp: the size of the user buffer
2863  * @ppos: file position
2864  * @ppos: the current position in the file
2865  *
2866  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2867  * values from/to the user buffer, treated as an ASCII string.
2868  * The values read are assumed to be in 1/1000 seconds, and
2869  * are converted into jiffies.
2870  *
2871  * Returns 0 on success.
2872  */
2873 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2874                              void __user *buffer, size_t *lenp, loff_t *ppos)
2875 {
2876         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2877                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2878 }
2879
2880 static int proc_do_cad_pid(struct ctl_table *table, int write,
2881                            void __user *buffer, size_t *lenp, loff_t *ppos)
2882 {
2883         struct pid *new_pid;
2884         pid_t tmp;
2885         int r;
2886
2887         tmp = pid_vnr(cad_pid);
2888
2889         r = __do_proc_dointvec(&tmp, table, write, buffer,
2890                                lenp, ppos, NULL, NULL);
2891         if (r || !write)
2892                 return r;
2893
2894         new_pid = find_get_pid(tmp);
2895         if (!new_pid)
2896                 return -ESRCH;
2897
2898         put_pid(xchg(&cad_pid, new_pid));
2899         return 0;
2900 }
2901
2902 #else /* CONFIG_PROC_FS */
2903
2904 int proc_dostring(struct ctl_table *table, int write,
2905                   void __user *buffer, size_t *lenp, loff_t *ppos)
2906 {
2907         return -ENOSYS;
2908 }
2909
2910 int proc_dointvec(struct ctl_table *table, int write,
2911                   void __user *buffer, size_t *lenp, loff_t *ppos)
2912 {
2913         return -ENOSYS;
2914 }
2915
2916 int proc_dointvec_minmax(struct ctl_table *table, int write,
2917                     void __user *buffer, size_t *lenp, loff_t *ppos)
2918 {
2919         return -ENOSYS;
2920 }
2921
2922 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2923                     void __user *buffer, size_t *lenp, loff_t *ppos)
2924 {
2925         return -ENOSYS;
2926 }
2927
2928 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2929                     void __user *buffer, size_t *lenp, loff_t *ppos)
2930 {
2931         return -ENOSYS;
2932 }
2933
2934 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2935                              void __user *buffer, size_t *lenp, loff_t *ppos)
2936 {
2937         return -ENOSYS;
2938 }
2939
2940 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2941                     void __user *buffer, size_t *lenp, loff_t *ppos)
2942 {
2943         return -ENOSYS;
2944 }
2945
2946 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2947                                       void __user *buffer,
2948                                       size_t *lenp, loff_t *ppos)
2949 {
2950     return -ENOSYS;
2951 }
2952
2953
2954 #endif /* CONFIG_PROC_FS */
2955
2956
2957 #ifdef CONFIG_SYSCTL_SYSCALL
2958 /*
2959  * General sysctl support routines
2960  */
2961
2962 /* The generic sysctl data routine (used if no strategy routine supplied) */
2963 int sysctl_data(struct ctl_table *table,
2964                 void __user *oldval, size_t __user *oldlenp,
2965                 void __user *newval, size_t newlen)
2966 {
2967         size_t len;
2968
2969         /* Get out of I don't have a variable */
2970         if (!table->data || !table->maxlen)
2971                 return -ENOTDIR;
2972
2973         if (oldval && oldlenp) {
2974                 if (get_user(len, oldlenp))
2975                         return -EFAULT;
2976                 if (len) {
2977                         if (len > table->maxlen)
2978                                 len = table->maxlen;
2979                         if (copy_to_user(oldval, table->data, len))
2980                                 return -EFAULT;
2981                         if (put_user(len, oldlenp))
2982                                 return -EFAULT;
2983                 }
2984         }
2985
2986         if (newval && newlen) {
2987                 if (newlen > table->maxlen)
2988                         newlen = table->maxlen;
2989
2990                 if (copy_from_user(table->data, newval, newlen))
2991                         return -EFAULT;
2992         }
2993         return 1;
2994 }
2995
2996 /* The generic string strategy routine: */
2997 int sysctl_string(struct ctl_table *table,
2998                   void __user *oldval, size_t __user *oldlenp,
2999                   void __user *newval, size_t newlen)
3000 {
3001         if (!table->data || !table->maxlen)
3002                 return -ENOTDIR;
3003
3004         if (oldval && oldlenp) {
3005                 size_t bufsize;
3006                 if (get_user(bufsize, oldlenp))
3007                         return -EFAULT;
3008                 if (bufsize) {
3009                         size_t len = strlen(table->data), copied;
3010
3011                         /* This shouldn't trigger for a well-formed sysctl */
3012                         if (len > table->maxlen)
3013                                 len = table->maxlen;
3014
3015                         /* Copy up to a max of bufsize-1 bytes of the string */
3016                         copied = (len >= bufsize) ? bufsize - 1 : len;
3017
3018                         if (copy_to_user(oldval, table->data, copied) ||
3019                             put_user(0, (char __user *)(oldval + copied)))
3020                                 return -EFAULT;
3021                         if (put_user(len, oldlenp))
3022                                 return -EFAULT;
3023                 }
3024         }
3025         if (newval && newlen) {
3026                 size_t len = newlen;
3027                 if (len > table->maxlen)
3028                         len = table->maxlen;
3029                 if(copy_from_user(table->data, newval, len))
3030                         return -EFAULT;
3031                 if (len == table->maxlen)
3032                         len--;
3033                 ((char *) table->data)[len] = 0;
3034         }
3035         return 1;
3036 }
3037
3038 /*
3039  * This function makes sure that all of the integers in the vector
3040  * are between the minimum and maximum values given in the arrays
3041  * table->extra1 and table->extra2, respectively.
3042  */
3043 int sysctl_intvec(struct ctl_table *table,
3044                 void __user *oldval, size_t __user *oldlenp,
3045                 void __user *newval, size_t newlen)
3046 {
3047
3048         if (newval && newlen) {
3049                 int __user *vec = (int __user *) newval;
3050                 int *min = (int *) table->extra1;
3051                 int *max = (int *) table->extra2;
3052                 size_t length;
3053                 int i;
3054
3055                 if (newlen % sizeof(int) != 0)
3056                         return -EINVAL;
3057
3058                 if (!table->extra1 && !table->extra2)
3059                         return 0;
3060
3061                 if (newlen > table->maxlen)
3062                         newlen = table->maxlen;
3063                 length = newlen / sizeof(int);
3064
3065                 for (i = 0; i < length; i++) {
3066                         int value;
3067                         if (get_user(value, vec + i))
3068                                 return -EFAULT;
3069                         if (min && value < min[i])
3070                                 return -EINVAL;
3071                         if (max && value > max[i])
3072                                 return -EINVAL;
3073                 }
3074         }
3075         return 0;
3076 }
3077
3078 /* Strategy function to convert jiffies to seconds */
3079 int sysctl_jiffies(struct ctl_table *table,
3080                 void __user *oldval, size_t __user *oldlenp,
3081                 void __user *newval, size_t newlen)
3082 {
3083         if (oldval && oldlenp) {
3084                 size_t olen;
3085
3086                 if (get_user(olen, oldlenp))
3087                         return -EFAULT;
3088                 if (olen) {
3089                         int val;
3090
3091                         if (olen < sizeof(int))
3092                                 return -EINVAL;
3093
3094                         val = *(int *)(table->data) / HZ;
3095                         if (put_user(val, (int __user *)oldval))
3096                                 return -EFAULT;
3097                         if (put_user(sizeof(int), oldlenp))
3098                                 return -EFAULT;
3099                 }
3100         }
3101         if (newval && newlen) {
3102                 int new;
3103                 if (newlen != sizeof(int))
3104                         return -EINVAL;
3105                 if (get_user(new, (int __user *)newval))
3106                         return -EFAULT;
3107                 *(int *)(table->data) = new*HZ;
3108         }
3109         return 1;
3110 }
3111
3112 /* Strategy function to convert jiffies to seconds */
3113 int sysctl_ms_jiffies(struct ctl_table *table,
3114                 void __user *oldval, size_t __user *oldlenp,
3115                 void __user *newval, size_t newlen)
3116 {
3117         if (oldval && oldlenp) {
3118                 size_t olen;
3119
3120                 if (get_user(olen, oldlenp))
3121                         return -EFAULT;
3122                 if (olen) {
3123                         int val;
3124
3125                         if (olen < sizeof(int))
3126                                 return -EINVAL;
3127
3128                         val = jiffies_to_msecs(*(int *)(table->data));
3129                         if (put_user(val, (int __user *)oldval))
3130                                 return -EFAULT;
3131                         if (put_user(sizeof(int), oldlenp))
3132                                 return -EFAULT;
3133                 }
3134         }
3135         if (newval && newlen) {
3136                 int new;
3137                 if (newlen != sizeof(int))
3138                         return -EINVAL;
3139                 if (get_user(new, (int __user *)newval))
3140                         return -EFAULT;
3141                 *(int *)(table->data) = msecs_to_jiffies(new);
3142         }
3143         return 1;
3144 }
3145
3146
3147
3148 #else /* CONFIG_SYSCTL_SYSCALL */
3149
3150
3151 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3152 {
3153         struct __sysctl_args tmp;
3154         int error;
3155
3156         if (copy_from_user(&tmp, args, sizeof(tmp)))
3157                 return -EFAULT;
3158
3159         error = deprecated_sysctl_warning(&tmp);
3160
3161         /* If no error reading the parameters then just -ENOSYS ... */
3162         if (!error)
3163                 error = -ENOSYS;
3164
3165         return error;
3166 }
3167
3168 int sysctl_data(struct ctl_table *table,
3169                   void __user *oldval, size_t __user *oldlenp,
3170                   void __user *newval, size_t newlen)
3171 {
3172         return -ENOSYS;
3173 }
3174
3175 int sysctl_string(struct ctl_table *table,
3176                   void __user *oldval, size_t __user *oldlenp,
3177                   void __user *newval, size_t newlen)
3178 {
3179         return -ENOSYS;
3180 }
3181
3182 int sysctl_intvec(struct ctl_table *table,
3183                 void __user *oldval, size_t __user *oldlenp,
3184                 void __user *newval, size_t newlen)
3185 {
3186         return -ENOSYS;
3187 }
3188
3189 int sysctl_jiffies(struct ctl_table *table,
3190                 void __user *oldval, size_t __user *oldlenp,
3191                 void __user *newval, size_t newlen)
3192 {
3193         return -ENOSYS;
3194 }
3195
3196 int sysctl_ms_jiffies(struct ctl_table *table,
3197                 void __user *oldval, size_t __user *oldlenp,
3198                 void __user *newval, size_t newlen)
3199 {
3200         return -ENOSYS;
3201 }
3202
3203 #endif /* CONFIG_SYSCTL_SYSCALL */
3204
3205 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3206 {
3207         static int msg_count;
3208         int name[CTL_MAXNAME];
3209         int i;
3210
3211         /* Check args->nlen. */
3212         if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3213                 return -ENOTDIR;
3214
3215         /* Read in the sysctl name for better debug message logging */
3216         for (i = 0; i < args->nlen; i++)
3217                 if (get_user(name[i], args->name + i))
3218                         return -EFAULT;
3219
3220         /* Ignore accesses to kernel.version */
3221         if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3222                 return 0;
3223
3224         if (msg_count < 5) {
3225                 msg_count++;
3226                 printk(KERN_INFO
3227                         "warning: process `%s' used the deprecated sysctl "
3228                         "system call with ", current->comm);
3229                 for (i = 0; i < args->nlen; i++)
3230                         printk("%d.", name[i]);
3231                 printk("\n");
3232         }
3233         return 0;
3234 }
3235
3236 /*
3237  * No sense putting this after each symbol definition, twice,
3238  * exception granted :-)
3239  */
3240 EXPORT_SYMBOL(proc_dointvec);
3241 EXPORT_SYMBOL(proc_dointvec_jiffies);
3242 EXPORT_SYMBOL(proc_dointvec_minmax);
3243 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3244 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3245 EXPORT_SYMBOL(proc_dostring);
3246 EXPORT_SYMBOL(proc_doulongvec_minmax);
3247 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3248 EXPORT_SYMBOL(register_sysctl_table);
3249 EXPORT_SYMBOL(register_sysctl_paths);
3250 EXPORT_SYMBOL(sysctl_intvec);
3251 EXPORT_SYMBOL(sysctl_jiffies);
3252 EXPORT_SYMBOL(sysctl_ms_jiffies);
3253 EXPORT_SYMBOL(sysctl_string);
3254 EXPORT_SYMBOL(sysctl_data);
3255 EXPORT_SYMBOL(unregister_sysctl_table);