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   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/mm.h>
  23 #include <linux/swap.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/security.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/kmemcheck.h>
  31 #include <linux/smp_lock.h>
  32 #include <linux/fs.h>
  33 #include <linux/init.h>
  34 #include <linux/kernel.h>
  35 #include <linux/kobject.h>
  36 #include <linux/net.h>
  37 #include <linux/sysrq.h>
  38 #include <linux/highuid.h>
  39 #include <linux/writeback.h>
  40 #include <linux/hugetlb.h>
  41 #include <linux/initrd.h>
  42 #include <linux/key.h>
  43 #include <linux/times.h>
  44 #include <linux/limits.h>
  45 #include <linux/dcache.h>
  46 #include <linux/syscalls.h>
  47 #include <linux/vmstat.h>
  48 #include <linux/nfs_fs.h>
  49 #include <linux/acpi.h>
  50 #include <linux/reboot.h>
  51 #include <linux/ftrace.h>
  52 #include <linux/slow-work.h>
  53 #include <linux/perf_event.h>
  54
  55 #include <asm/uaccess.h>
  56 #include <asm/processor.h>
  57
  58 #ifdef CONFIG_X86
  59 #include <asm/nmi.h>
  60 #include <asm/stacktrace.h>
  61 #include <asm/io.h>
  62 #endif
  63
  64 static int deprecated_sysctl_warning(struct __sysctl_args *args);
  65
  66 #if defined(CONFIG_SYSCTL)
  67
  68 /* External variables not in a header file. */
  69 extern int C_A_D;
  70 extern int print_fatal_signals;
  71 extern int sysctl_overcommit_memory;
  72 extern int sysctl_overcommit_ratio;
  73 extern int sysctl_panic_on_oom;
  74 extern int sysctl_oom_kill_allocating_task;
  75 extern int sysctl_oom_dump_tasks;
  76 extern int max_threads;
  77 extern int core_uses_pid;
  78 extern int suid_dumpable;
  79 extern char core_pattern[];
  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, struct file *filp,
 167                   void __user *buffer, size_t *lenp, loff_t *ppos);
 168 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
 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 #ifdef CONFIG_PROC_SYSCTL
 428         {
 429                 .procname       = "tainted",
 430                 .maxlen         = sizeof(long),
 431                 .mode           = 0644,
 432                 .proc_handler   = &proc_taint,
 433         },
 434 #endif
 435 #ifdef CONFIG_LATENCYTOP
 436         {
 437                 .procname       = "latencytop",
 438                 .data           = &latencytop_enabled,
 439                 .maxlen         = sizeof(int),
 440                 .mode           = 0644,
 441                 .proc_handler   = &proc_dointvec,
 442         },
 443 #endif
 444 #ifdef CONFIG_BLK_DEV_INITRD
 445         {
 446                 .ctl_name       = KERN_REALROOTDEV,
 447                 .procname       = "real-root-dev",
 448                 .data           = &real_root_dev,
 449                 .maxlen         = sizeof(int),
 450                 .mode           = 0644,
 451                 .proc_handler   = &proc_dointvec,
 452         },
 453 #endif
 454         {
 455                 .ctl_name       = CTL_UNNUMBERED,
 456                 .procname       = "print-fatal-signals",
 457                 .data           = &print_fatal_signals,
 458                 .maxlen         = sizeof(int),
 459                 .mode           = 0644,
 460                 .proc_handler   = &proc_dointvec,
 461         },
 462 #ifdef CONFIG_SPARC
 463         {
 464                 .ctl_name       = KERN_SPARC_REBOOT,
 465                 .procname       = "reboot-cmd",
 466                 .data           = reboot_command,
 467                 .maxlen         = 256,
 468                 .mode           = 0644,
 469                 .proc_handler   = &proc_dostring,
 470                 .strategy       = &sysctl_string,
 471         },
 472         {
 473                 .ctl_name       = KERN_SPARC_STOP_A,
 474                 .procname       = "stop-a",
 475                 .data           = &stop_a_enabled,
 476                 .maxlen         = sizeof (int),
 477                 .mode           = 0644,
 478                 .proc_handler   = &proc_dointvec,
 479         },
 480         {
 481                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 482                 .procname       = "scons-poweroff",
 483                 .data           = &scons_pwroff,
 484                 .maxlen         = sizeof (int),
 485                 .mode           = 0644,
 486                 .proc_handler   = &proc_dointvec,
 487         },
 488 #endif
 489 #ifdef CONFIG_SPARC64
 490         {
 491                 .ctl_name       = CTL_UNNUMBERED,
 492                 .procname       = "tsb-ratio",
 493                 .data           = &sysctl_tsb_ratio,
 494                 .maxlen         = sizeof (int),
 495                 .mode           = 0644,
 496                 .proc_handler   = &proc_dointvec,
 497         },
 498 #endif
 499 #ifdef __hppa__
 500         {
 501                 .ctl_name       = KERN_HPPA_PWRSW,
 502                 .procname       = "soft-power",
 503                 .data           = &pwrsw_enabled,
 504                 .maxlen         = sizeof (int),
 505                 .mode           = 0644,
 506                 .proc_handler   = &proc_dointvec,
 507         },
 508         {
 509                 .ctl_name       = KERN_HPPA_UNALIGNED,
 510                 .procname       = "unaligned-trap",
 511                 .data           = &unaligned_enabled,
 512                 .maxlen         = sizeof (int),
 513                 .mode           = 0644,
 514                 .proc_handler   = &proc_dointvec,
 515         },
 516 #endif
 517         {
 518                 .ctl_name       = KERN_CTLALTDEL,
 519                 .procname       = "ctrl-alt-del",
 520                 .data           = &C_A_D,
 521                 .maxlen         = sizeof(int),
 522                 .mode           = 0644,
 523                 .proc_handler   = &proc_dointvec,
 524         },
 525 #ifdef CONFIG_FUNCTION_TRACER
 526         {
 527                 .ctl_name       = CTL_UNNUMBERED,
 528                 .procname       = "ftrace_enabled",
 529                 .data           = &ftrace_enabled,
 530                 .maxlen         = sizeof(int),
 531                 .mode           = 0644,
 532                 .proc_handler   = &ftrace_enable_sysctl,
 533         },
 534 #endif
 535 #ifdef CONFIG_STACK_TRACER
 536         {
 537                 .ctl_name       = CTL_UNNUMBERED,
 538                 .procname       = "stack_tracer_enabled",
 539                 .data           = &stack_tracer_enabled,
 540                 .maxlen         = sizeof(int),
 541                 .mode           = 0644,
 542                 .proc_handler   = &stack_trace_sysctl,
 543         },
 544 #endif
 545 #ifdef CONFIG_TRACING
 546         {
 547                 .ctl_name       = CTL_UNNUMBERED,
 548                 .procname       = "ftrace_dump_on_oops",
 549                 .data           = &ftrace_dump_on_oops,
 550                 .maxlen         = sizeof(int),
 551                 .mode           = 0644,
 552                 .proc_handler   = &proc_dointvec,
 553         },
 554 #endif
 555 #ifdef CONFIG_MODULES
 556         {
 557                 .ctl_name       = KERN_MODPROBE,
 558                 .procname       = "modprobe",
 559                 .data           = &modprobe_path,
 560                 .maxlen         = KMOD_PATH_LEN,
 561                 .mode           = 0644,
 562                 .proc_handler   = &proc_dostring,
 563                 .strategy       = &sysctl_string,
 564         },
 565         {
 566                 .ctl_name       = CTL_UNNUMBERED,
 567                 .procname       = "modules_disabled",
 568                 .data           = &modules_disabled,
 569                 .maxlen         = sizeof(int),
 570                 .mode           = 0644,
 571                 /* only handle a transition from default "0" to "1" */
 572                 .proc_handler   = &proc_dointvec_minmax,
 573                 .extra1         = &one,
 574                 .extra2         = &one,
 575         },
 576 #endif
 577 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 578         {
 579                 .ctl_name       = KERN_HOTPLUG,
 580                 .procname       = "hotplug",
 581                 .data           = &uevent_helper,
 582                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 583                 .mode           = 0644,
 584                 .proc_handler   = &proc_dostring,
 585                 .strategy       = &sysctl_string,
 586         },
 587 #endif
 588 #ifdef CONFIG_CHR_DEV_SG
 589         {
 590                 .ctl_name       = KERN_SG_BIG_BUFF,
 591                 .procname       = "sg-big-buff",
 592                 .data           = &sg_big_buff,
 593                 .maxlen         = sizeof (int),
 594                 .mode           = 0444,
 595                 .proc_handler   = &proc_dointvec,
 596         },
 597 #endif
 598 #ifdef CONFIG_BSD_PROCESS_ACCT
 599         {
 600                 .ctl_name       = KERN_ACCT,
 601                 .procname       = "acct",
 602                 .data           = &acct_parm,
 603                 .maxlen         = 3*sizeof(int),
 604                 .mode           = 0644,
 605                 .proc_handler   = &proc_dointvec,
 606         },
 607 #endif
 608 #ifdef CONFIG_MAGIC_SYSRQ
 609         {
 610                 .ctl_name       = KERN_SYSRQ,
 611                 .procname       = "sysrq",
 612                 .data           = &__sysrq_enabled,
 613                 .maxlen         = sizeof (int),
 614                 .mode           = 0644,
 615                 .proc_handler   = &proc_dointvec,
 616         },
 617 #endif
 618 #ifdef CONFIG_PROC_SYSCTL
 619         {
 620                 .procname       = "cad_pid",
 621                 .data           = NULL,
 622                 .maxlen         = sizeof (int),
 623                 .mode           = 0600,
 624                 .proc_handler   = &proc_do_cad_pid,
 625         },
 626 #endif
 627         {
 628                 .ctl_name       = KERN_MAX_THREADS,
 629                 .procname       = "threads-max",
 630                 .data           = &max_threads,
 631                 .maxlen         = sizeof(int),
 632                 .mode           = 0644,
 633                 .proc_handler   = &proc_dointvec,
 634         },
 635         {
 636                 .ctl_name       = KERN_RANDOM,
 637                 .procname       = "random",
 638                 .mode           = 0555,
 639                 .child          = random_table,
 640         },
 641         {
 642                 .ctl_name       = KERN_OVERFLOWUID,
 643                 .procname       = "overflowuid",
 644                 .data           = &overflowuid,
 645                 .maxlen         = sizeof(int),
 646                 .mode           = 0644,
 647                 .proc_handler   = &proc_dointvec_minmax,
 648                 .strategy       = &sysctl_intvec,
 649                 .extra1         = &minolduid,
 650                 .extra2         = &maxolduid,
 651         },
 652         {
 653                 .ctl_name       = KERN_OVERFLOWGID,
 654                 .procname       = "overflowgid",
 655                 .data           = &overflowgid,
 656                 .maxlen         = sizeof(int),
 657                 .mode           = 0644,
 658                 .proc_handler   = &proc_dointvec_minmax,
 659                 .strategy       = &sysctl_intvec,
 660                 .extra1         = &minolduid,
 661                 .extra2         = &maxolduid,
 662         },
 663 #ifdef CONFIG_S390
 664 #ifdef CONFIG_MATHEMU
 665         {
 666                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 667                 .procname       = "ieee_emulation_warnings",
 668                 .data           = &sysctl_ieee_emulation_warnings,
 669                 .maxlen         = sizeof(int),
 670                 .mode           = 0644,
 671                 .proc_handler   = &proc_dointvec,
 672         },
 673 #endif
 674         {
 675                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 676                 .procname       = "userprocess_debug",
 677                 .data           = &sysctl_userprocess_debug,
 678                 .maxlen         = sizeof(int),
 679                 .mode           = 0644,
 680                 .proc_handler   = &proc_dointvec,
 681         },
 682 #endif
 683         {
 684                 .ctl_name       = KERN_PIDMAX,
 685                 .procname       = "pid_max",
 686                 .data           = &pid_max,
 687                 .maxlen         = sizeof (int),
 688                 .mode           = 0644,
 689                 .proc_handler   = &proc_dointvec_minmax,
 690                 .strategy       = sysctl_intvec,
 691                 .extra1         = &pid_max_min,
 692                 .extra2         = &pid_max_max,
 693         },
 694         {
 695                 .ctl_name       = KERN_PANIC_ON_OOPS,
 696                 .procname       = "panic_on_oops",
 697                 .data           = &panic_on_oops,
 698                 .maxlen         = sizeof(int),
 699                 .mode           = 0644,
 700                 .proc_handler   = &proc_dointvec,
 701         },
 702 #if defined CONFIG_PRINTK
 703         {
 704                 .ctl_name       = KERN_PRINTK,
 705                 .procname       = "printk",
 706                 .data           = &console_loglevel,
 707                 .maxlen         = 4*sizeof(int),
 708                 .mode           = 0644,
 709                 .proc_handler   = &proc_dointvec,
 710         },
 711         {
 712                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 713                 .procname       = "printk_ratelimit",
 714                 .data           = &printk_ratelimit_state.interval,
 715                 .maxlen         = sizeof(int),
 716                 .mode           = 0644,
 717                 .proc_handler   = &proc_dointvec_jiffies,
 718                 .strategy       = &sysctl_jiffies,
 719         },
 720         {
 721                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 722                 .procname       = "printk_ratelimit_burst",
 723                 .data           = &printk_ratelimit_state.burst,
 724                 .maxlen         = sizeof(int),
 725                 .mode           = 0644,
 726                 .proc_handler   = &proc_dointvec,
 727         },
 728         {
 729                 .ctl_name       = CTL_UNNUMBERED,
 730                 .procname       = "printk_delay",
 731                 .data           = &printk_delay_msec,
 732                 .maxlen         = sizeof(int),
 733                 .mode           = 0644,
 734                 .proc_handler   = &proc_dointvec_minmax,
 735                 .strategy       = &sysctl_intvec,
 736                 .extra1         = &zero,
 737                 .extra2         = &ten_thousand,
 738         },
 739 #endif
 740         {
 741                 .ctl_name       = KERN_NGROUPS_MAX,
 742                 .procname       = "ngroups_max",
 743                 .data           = &ngroups_max,
 744                 .maxlen         = sizeof (int),
 745                 .mode           = 0444,
 746                 .proc_handler   = &proc_dointvec,
 747         },
 748 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 749         {
 750                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 751                 .procname       = "unknown_nmi_panic",
 752                 .data           = &unknown_nmi_panic,
 753                 .maxlen         = sizeof (int),
 754                 .mode           = 0644,
 755                 .proc_handler   = &proc_dointvec,
 756         },
 757         {
 758                 .procname       = "nmi_watchdog",
 759                 .data           = &nmi_watchdog_enabled,
 760                 .maxlen         = sizeof (int),
 761                 .mode           = 0644,
 762                 .proc_handler   = &proc_nmi_enabled,
 763         },
 764 #endif
 765 #if defined(CONFIG_X86)
 766         {
 767                 .ctl_name       = KERN_PANIC_ON_NMI,
 768                 .procname       = "panic_on_unrecovered_nmi",
 769                 .data           = &panic_on_unrecovered_nmi,
 770                 .maxlen         = sizeof(int),
 771                 .mode           = 0644,
 772                 .proc_handler   = &proc_dointvec,
 773         },
 774         {
 775                 .ctl_name       = CTL_UNNUMBERED,
 776                 .procname       = "panic_on_io_nmi",
 777                 .data           = &panic_on_io_nmi,
 778                 .maxlen         = sizeof(int),
 779                 .mode           = 0644,
 780                 .proc_handler   = &proc_dointvec,
 781         },
 782         {
 783                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 784                 .procname       = "bootloader_type",
 785                 .data           = &bootloader_type,
 786                 .maxlen         = sizeof (int),
 787                 .mode           = 0444,
 788                 .proc_handler   = &proc_dointvec,
 789         },
 790         {
 791                 .ctl_name       = CTL_UNNUMBERED,
 792                 .procname       = "bootloader_version",
 793                 .data           = &bootloader_version,
 794                 .maxlen         = sizeof (int),
 795                 .mode           = 0444,
 796                 .proc_handler   = &proc_dointvec,
 797         },
 798         {
 799                 .ctl_name       = CTL_UNNUMBERED,
 800                 .procname       = "kstack_depth_to_print",
 801                 .data           = &kstack_depth_to_print,
 802                 .maxlen         = sizeof(int),
 803                 .mode           = 0644,
 804                 .proc_handler   = &proc_dointvec,
 805         },
 806         {
 807                 .ctl_name       = CTL_UNNUMBERED,
 808                 .procname       = "io_delay_type",
 809                 .data           = &io_delay_type,
 810                 .maxlen         = sizeof(int),
 811                 .mode           = 0644,
 812                 .proc_handler   = &proc_dointvec,
 813         },
 814 #endif
 815 #if defined(CONFIG_MMU)
 816         {
 817                 .ctl_name       = KERN_RANDOMIZE,
 818                 .procname       = "randomize_va_space",
 819                 .data           = &randomize_va_space,
 820                 .maxlen         = sizeof(int),
 821                 .mode           = 0644,
 822                 .proc_handler   = &proc_dointvec,
 823         },
 824 #endif
 825 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 826         {
 827                 .ctl_name       = KERN_SPIN_RETRY,
 828                 .procname       = "spin_retry",
 829                 .data           = &spin_retry,
 830                 .maxlen         = sizeof (int),
 831                 .mode           = 0644,
 832                 .proc_handler   = &proc_dointvec,
 833         },
 834 #endif
 835 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 836         {
 837                 .procname       = "acpi_video_flags",
 838                 .data           = &acpi_realmode_flags,
 839                 .maxlen         = sizeof (unsigned long),
 840                 .mode           = 0644,
 841                 .proc_handler   = &proc_doulongvec_minmax,
 842         },
 843 #endif
 844 #ifdef CONFIG_IA64
 845         {
 846                 .ctl_name       = KERN_IA64_UNALIGNED,
 847                 .procname       = "ignore-unaligned-usertrap",
 848                 .data           = &no_unaligned_warning,
 849                 .maxlen         = sizeof (int),
 850                 .mode           = 0644,
 851                 .proc_handler   = &proc_dointvec,
 852         },
 853         {
 854                 .ctl_name       = CTL_UNNUMBERED,
 855                 .procname       = "unaligned-dump-stack",
 856                 .data           = &unaligned_dump_stack,
 857                 .maxlen         = sizeof (int),
 858                 .mode           = 0644,
 859                 .proc_handler   = &proc_dointvec,
 860         },
 861 #endif
 862 #ifdef CONFIG_DETECT_SOFTLOCKUP
 863         {
 864                 .ctl_name       = CTL_UNNUMBERED,
 865                 .procname       = "softlockup_panic",
 866                 .data           = &softlockup_panic,
 867                 .maxlen         = sizeof(int),
 868                 .mode           = 0644,
 869                 .proc_handler   = &proc_dointvec_minmax,
 870                 .strategy       = &sysctl_intvec,
 871                 .extra1         = &zero,
 872                 .extra2         = &one,
 873         },
 874         {
 875                 .ctl_name       = CTL_UNNUMBERED,
 876                 .procname       = "softlockup_thresh",
 877                 .data           = &softlockup_thresh,
 878                 .maxlen         = sizeof(int),
 879                 .mode           = 0644,
 880                 .proc_handler   = &proc_dosoftlockup_thresh,
 881                 .strategy       = &sysctl_intvec,
 882                 .extra1         = &neg_one,
 883                 .extra2         = &sixty,
 884         },
 885 #endif
 886 #ifdef CONFIG_DETECT_HUNG_TASK
 887         {
 888                 .ctl_name       = CTL_UNNUMBERED,
 889                 .procname       = "hung_task_panic",
 890                 .data           = &sysctl_hung_task_panic,
 891                 .maxlen         = sizeof(int),
 892                 .mode           = 0644,
 893                 .proc_handler   = &proc_dointvec_minmax,
 894                 .strategy       = &sysctl_intvec,
 895                 .extra1         = &zero,
 896                 .extra2         = &one,
 897         },
 898         {
 899                 .ctl_name       = CTL_UNNUMBERED,
 900                 .procname       = "hung_task_check_count",
 901                 .data           = &sysctl_hung_task_check_count,
 902                 .maxlen         = sizeof(unsigned long),
 903                 .mode           = 0644,
 904                 .proc_handler   = &proc_doulongvec_minmax,
 905                 .strategy       = &sysctl_intvec,
 906         },
 907         {
 908                 .ctl_name       = CTL_UNNUMBERED,
 909                 .procname       = "hung_task_timeout_secs",
 910                 .data           = &sysctl_hung_task_timeout_secs,
 911                 .maxlen         = sizeof(unsigned long),
 912                 .mode           = 0644,
 913                 .proc_handler   = &proc_dohung_task_timeout_secs,
 914                 .strategy       = &sysctl_intvec,
 915         },
 916         {
 917                 .ctl_name       = CTL_UNNUMBERED,
 918                 .procname       = "hung_task_warnings",
 919                 .data           = &sysctl_hung_task_warnings,
 920                 .maxlen         = sizeof(unsigned long),
 921                 .mode           = 0644,
 922                 .proc_handler   = &proc_doulongvec_minmax,
 923                 .strategy       = &sysctl_intvec,
 924         },
 925 #endif
 926 #ifdef CONFIG_COMPAT
 927         {
 928                 .ctl_name       = KERN_COMPAT_LOG,
 929                 .procname       = "compat-log",
 930                 .data           = &compat_log,
 931                 .maxlen         = sizeof (int),
 932                 .mode           = 0644,
 933                 .proc_handler   = &proc_dointvec,
 934         },
 935 #endif
 936 #ifdef CONFIG_RT_MUTEXES
 937         {
 938                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 939                 .procname       = "max_lock_depth",
 940                 .data           = &max_lock_depth,
 941                 .maxlen         = sizeof(int),
 942                 .mode           = 0644,
 943                 .proc_handler   = &proc_dointvec,
 944         },
 945 #endif
 946         {
 947                 .ctl_name       = CTL_UNNUMBERED,
 948                 .procname       = "poweroff_cmd",
 949                 .data           = &poweroff_cmd,
 950                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 951                 .mode           = 0644,
 952                 .proc_handler   = &proc_dostring,
 953                 .strategy       = &sysctl_string,
 954         },
 955 #ifdef CONFIG_KEYS
 956         {
 957                 .ctl_name       = CTL_UNNUMBERED,
 958                 .procname       = "keys",
 959                 .mode           = 0555,
 960                 .child          = key_sysctls,
 961         },
 962 #endif
 963 #ifdef CONFIG_RCU_TORTURE_TEST
 964         {
 965                 .ctl_name       = CTL_UNNUMBERED,
 966                 .procname       = "rcutorture_runnable",
 967                 .data           = &rcutorture_runnable,
 968                 .maxlen         = sizeof(int),
 969                 .mode           = 0644,
 970                 .proc_handler   = &proc_dointvec,
 971         },
 972 #endif
 973 #ifdef CONFIG_SLOW_WORK
 974         {
 975                 .ctl_name       = CTL_UNNUMBERED,
 976                 .procname       = "slow-work",
 977                 .mode           = 0555,
 978                 .child          = slow_work_sysctls,
 979         },
 980 #endif
 981 #ifdef CONFIG_PERF_EVENTS
 982         {
 983                 .ctl_name       = CTL_UNNUMBERED,
 984                 .procname       = "perf_event_paranoid",
 985                 .data           = &sysctl_perf_event_paranoid,
 986                 .maxlen         = sizeof(sysctl_perf_event_paranoid),
 987                 .mode           = 0644,
 988                 .proc_handler   = &proc_dointvec,
 989         },
 990         {
 991                 .ctl_name       = CTL_UNNUMBERED,
 992                 .procname       = "perf_event_mlock_kb",
 993                 .data           = &sysctl_perf_event_mlock,
 994                 .maxlen         = sizeof(sysctl_perf_event_mlock),
 995                 .mode           = 0644,
 996                 .proc_handler   = &proc_dointvec,
 997         },
 998         {
 999                 .ctl_name       = CTL_UNNUMBERED,
1000                 .procname       = "perf_event_max_sample_rate",
1001                 .data           = &sysctl_perf_event_sample_rate,
1002                 .maxlen         = sizeof(sysctl_perf_event_sample_rate),
1003                 .mode           = 0644,
1004                 .proc_handler   = &proc_dointvec,
1005         },
1006 #endif
1007 #ifdef CONFIG_KMEMCHECK
1008         {
1009                 .ctl_name       = CTL_UNNUMBERED,
1010                 .procname       = "kmemcheck",
1011                 .data           = &kmemcheck_enabled,
1012                 .maxlen         = sizeof(int),
1013                 .mode           = 0644,
1014                 .proc_handler   = &proc_dointvec,
1015         },
1016 #endif
1017 #ifdef CONFIG_BLOCK
1018         {
1019                 .ctl_name       = CTL_UNNUMBERED,
1020                 .procname       = "blk_iopoll",
1021                 .data           = &blk_iopoll_enabled,
1022                 .maxlen         = sizeof(int),
1023                 .mode           = 0644,
1024                 .proc_handler   = &proc_dointvec,
1025         },
1026 #endif
1027 /*
1028  * NOTE: do not add new entries to this table unless you have read
1029  * Documentation/sysctl/ctl_unnumbered.txt
1030  */
1031         { .ctl_name = 0 }
1032 };
1033
1034 static struct ctl_table vm_table[] = {
1035         {
1036                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
1037                 .procname       = "overcommit_memory",
1038                 .data           = &sysctl_overcommit_memory,
1039                 .maxlen         = sizeof(sysctl_overcommit_memory),
1040                 .mode           = 0644,
1041                 .proc_handler   = &proc_dointvec,
1042         },
1043         {
1044                 .ctl_name       = VM_PANIC_ON_OOM,
1045                 .procname       = "panic_on_oom",
1046                 .data           = &sysctl_panic_on_oom,
1047                 .maxlen         = sizeof(sysctl_panic_on_oom),
1048                 .mode           = 0644,
1049                 .proc_handler   = &proc_dointvec,
1050         },
1051         {
1052                 .ctl_name       = CTL_UNNUMBERED,
1053                 .procname       = "oom_kill_allocating_task",
1054                 .data           = &sysctl_oom_kill_allocating_task,
1055                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
1056                 .mode           = 0644,
1057                 .proc_handler   = &proc_dointvec,
1058         },
1059         {
1060                 .ctl_name       = CTL_UNNUMBERED,
1061                 .procname       = "oom_dump_tasks",
1062                 .data           = &sysctl_oom_dump_tasks,
1063                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
1064                 .mode           = 0644,
1065                 .proc_handler   = &proc_dointvec,
1066         },
1067         {
1068                 .ctl_name       = VM_OVERCOMMIT_RATIO,
1069                 .procname       = "overcommit_ratio",
1070                 .data           = &sysctl_overcommit_ratio,
1071                 .maxlen         = sizeof(sysctl_overcommit_ratio),
1072                 .mode           = 0644,
1073                 .proc_handler   = &proc_dointvec,
1074         },
1075         {
1076                 .ctl_name       = VM_PAGE_CLUSTER,
1077                 .procname       = "page-cluster",
1078                 .data           = &page_cluster,
1079                 .maxlen         = sizeof(int),
1080                 .mode           = 0644,
1081                 .proc_handler   = &proc_dointvec,
1082         },
1083         {
1084                 .ctl_name       = VM_DIRTY_BACKGROUND,
1085                 .procname       = "dirty_background_ratio",
1086                 .data           = &dirty_background_ratio,
1087                 .maxlen         = sizeof(dirty_background_ratio),
1088                 .mode           = 0644,
1089                 .proc_handler   = &dirty_background_ratio_handler,
1090                 .strategy       = &sysctl_intvec,
1091                 .extra1         = &zero,
1092                 .extra2         = &one_hundred,
1093         },
1094         {
1095                 .ctl_name       = CTL_UNNUMBERED,
1096                 .procname       = "dirty_background_bytes",
1097                 .data           = &dirty_background_bytes,
1098                 .maxlen         = sizeof(dirty_background_bytes),
1099                 .mode           = 0644,
1100                 .proc_handler   = &dirty_background_bytes_handler,
1101                 .strategy       = &sysctl_intvec,
1102                 .extra1         = &one_ul,
1103         },
1104         {
1105                 .ctl_name       = VM_DIRTY_RATIO,
1106                 .procname       = "dirty_ratio",
1107                 .data           = &vm_dirty_ratio,
1108                 .maxlen         = sizeof(vm_dirty_ratio),
1109                 .mode           = 0644,
1110                 .proc_handler   = &dirty_ratio_handler,
1111                 .strategy       = &sysctl_intvec,
1112                 .extra1         = &zero,
1113                 .extra2         = &one_hundred,
1114         },
1115         {
1116                 .ctl_name       = CTL_UNNUMBERED,
1117                 .procname       = "dirty_bytes",
1118                 .data           = &vm_dirty_bytes,
1119                 .maxlen         = sizeof(vm_dirty_bytes),
1120                 .mode           = 0644,
1121                 .proc_handler   = &dirty_bytes_handler,
1122                 .strategy       = &sysctl_intvec,
1123                 .extra1         = &dirty_bytes_min,
1124         },
1125         {
1126                 .procname       = "dirty_writeback_centisecs",
1127                 .data           = &dirty_writeback_interval,
1128                 .maxlen         = sizeof(dirty_writeback_interval),
1129                 .mode           = 0644,
1130                 .proc_handler   = &dirty_writeback_centisecs_handler,
1131         },
1132         {
1133                 .procname       = "dirty_expire_centisecs",
1134                 .data           = &dirty_expire_interval,
1135                 .maxlen         = sizeof(dirty_expire_interval),
1136                 .mode           = 0644,
1137                 .proc_handler   = &proc_dointvec,
1138         },
1139         {
1140                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
1141                 .procname       = "nr_pdflush_threads",
1142                 .data           = &nr_pdflush_threads,
1143                 .maxlen         = sizeof nr_pdflush_threads,
1144                 .mode           = 0444 /* read-only*/,
1145                 .proc_handler   = &proc_dointvec,
1146         },
1147         {
1148                 .ctl_name       = VM_SWAPPINESS,
1149                 .procname       = "swappiness",
1150                 .data           = &vm_swappiness,
1151                 .maxlen         = sizeof(vm_swappiness),
1152                 .mode           = 0644,
1153                 .proc_handler   = &proc_dointvec_minmax,
1154                 .strategy       = &sysctl_intvec,
1155                 .extra1         = &zero,
1156                 .extra2         = &one_hundred,
1157         },
1158 #ifdef CONFIG_HUGETLB_PAGE
1159          {
1160                 .procname       = "nr_hugepages",
1161                 .data           = NULL,
1162                 .maxlen         = sizeof(unsigned long),
1163                 .mode           = 0644,
1164                 .proc_handler   = &hugetlb_sysctl_handler,
1165                 .extra1         = (void *)&hugetlb_zero,
1166                 .extra2         = (void *)&hugetlb_infinity,
1167          },
1168          {
1169                 .ctl_name       = VM_HUGETLB_GROUP,
1170                 .procname       = "hugetlb_shm_group",
1171                 .data           = &sysctl_hugetlb_shm_group,
1172                 .maxlen         = sizeof(gid_t),
1173                 .mode           = 0644,
1174                 .proc_handler   = &proc_dointvec,
1175          },
1176          {
1177                 .ctl_name       = CTL_UNNUMBERED,
1178                 .procname       = "hugepages_treat_as_movable",
1179                 .data           = &hugepages_treat_as_movable,
1180                 .maxlen         = sizeof(int),
1181                 .mode           = 0644,
1182                 .proc_handler   = &hugetlb_treat_movable_handler,
1183         },
1184         {
1185                 .ctl_name       = CTL_UNNUMBERED,
1186                 .procname       = "nr_overcommit_hugepages",
1187                 .data           = NULL,
1188                 .maxlen         = sizeof(unsigned long),
1189                 .mode           = 0644,
1190                 .proc_handler   = &hugetlb_overcommit_handler,
1191                 .extra1         = (void *)&hugetlb_zero,
1192                 .extra2         = (void *)&hugetlb_infinity,
1193         },
1194 #endif
1195         {
1196                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
1197                 .procname       = "lowmem_reserve_ratio",
1198                 .data           = &sysctl_lowmem_reserve_ratio,
1199                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1200                 .mode           = 0644,
1201                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
1202                 .strategy       = &sysctl_intvec,
1203         },
1204         {
1205                 .ctl_name       = VM_DROP_PAGECACHE,
1206                 .procname       = "drop_caches",
1207                 .data           = &sysctl_drop_caches,
1208                 .maxlen         = sizeof(int),
1209                 .mode           = 0644,
1210                 .proc_handler   = drop_caches_sysctl_handler,
1211                 .strategy       = &sysctl_intvec,
1212         },
1213         {
1214                 .ctl_name       = VM_MIN_FREE_KBYTES,
1215                 .procname       = "min_free_kbytes",
1216                 .data           = &min_free_kbytes,
1217                 .maxlen         = sizeof(min_free_kbytes),
1218                 .mode           = 0644,
1219                 .proc_handler   = &min_free_kbytes_sysctl_handler,
1220                 .strategy       = &sysctl_intvec,
1221                 .extra1         = &zero,
1222         },
1223         {
1224                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
1225                 .procname       = "percpu_pagelist_fraction",
1226                 .data           = &percpu_pagelist_fraction,
1227                 .maxlen         = sizeof(percpu_pagelist_fraction),
1228                 .mode           = 0644,
1229                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
1230                 .strategy       = &sysctl_intvec,
1231                 .extra1         = &min_percpu_pagelist_fract,
1232         },
1233 #ifdef CONFIG_MMU
1234         {
1235                 .ctl_name       = VM_MAX_MAP_COUNT,
1236                 .procname       = "max_map_count",
1237                 .data           = &sysctl_max_map_count,
1238                 .maxlen         = sizeof(sysctl_max_map_count),
1239                 .mode           = 0644,
1240                 .proc_handler   = &proc_dointvec
1241         },
1242 #else
1243         {
1244                 .ctl_name       = CTL_UNNUMBERED,
1245                 .procname       = "nr_trim_pages",
1246                 .data           = &sysctl_nr_trim_pages,
1247                 .maxlen         = sizeof(sysctl_nr_trim_pages),
1248                 .mode           = 0644,
1249                 .proc_handler   = &proc_dointvec_minmax,
1250                 .strategy       = &sysctl_intvec,
1251                 .extra1         = &zero,
1252         },
1253 #endif
1254         {
1255                 .ctl_name       = VM_LAPTOP_MODE,
1256                 .procname       = "laptop_mode",
1257                 .data           = &laptop_mode,
1258                 .maxlen         = sizeof(laptop_mode),
1259                 .mode           = 0644,
1260                 .proc_handler   = &proc_dointvec_jiffies,
1261                 .strategy       = &sysctl_jiffies,
1262         },
1263         {
1264                 .ctl_name       = VM_BLOCK_DUMP,
1265                 .procname       = "block_dump",
1266                 .data           = &block_dump,
1267                 .maxlen         = sizeof(block_dump),
1268                 .mode           = 0644,
1269                 .proc_handler   = &proc_dointvec,
1270                 .strategy       = &sysctl_intvec,
1271                 .extra1         = &zero,
1272         },
1273         {
1274                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
1275                 .procname       = "vfs_cache_pressure",
1276                 .data           = &sysctl_vfs_cache_pressure,
1277                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1278                 .mode           = 0644,
1279                 .proc_handler   = &proc_dointvec,
1280                 .strategy       = &sysctl_intvec,
1281                 .extra1         = &zero,
1282         },
1283 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1284         {
1285                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
1286                 .procname       = "legacy_va_layout",
1287                 .data           = &sysctl_legacy_va_layout,
1288                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1289                 .mode           = 0644,
1290                 .proc_handler   = &proc_dointvec,
1291                 .strategy       = &sysctl_intvec,
1292                 .extra1         = &zero,
1293         },
1294 #endif
1295 #ifdef CONFIG_NUMA
1296         {
1297                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
1298                 .procname       = "zone_reclaim_mode",
1299                 .data           = &zone_reclaim_mode,
1300                 .maxlen         = sizeof(zone_reclaim_mode),
1301                 .mode           = 0644,
1302                 .proc_handler   = &proc_dointvec,
1303                 .strategy       = &sysctl_intvec,
1304                 .extra1         = &zero,
1305         },
1306         {
1307                 .ctl_name       = VM_MIN_UNMAPPED,
1308                 .procname       = "min_unmapped_ratio",
1309                 .data           = &sysctl_min_unmapped_ratio,
1310                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1311                 .mode           = 0644,
1312                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1313                 .strategy       = &sysctl_intvec,
1314                 .extra1         = &zero,
1315                 .extra2         = &one_hundred,
1316         },
1317         {
1318                 .ctl_name       = VM_MIN_SLAB,
1319                 .procname       = "min_slab_ratio",
1320                 .data           = &sysctl_min_slab_ratio,
1321                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1322                 .mode           = 0644,
1323                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1324                 .strategy       = &sysctl_intvec,
1325                 .extra1         = &zero,
1326                 .extra2         = &one_hundred,
1327         },
1328 #endif
1329 #ifdef CONFIG_SMP
1330         {
1331                 .ctl_name       = CTL_UNNUMBERED,
1332                 .procname       = "stat_interval",
1333                 .data           = &sysctl_stat_interval,
1334                 .maxlen         = sizeof(sysctl_stat_interval),
1335                 .mode           = 0644,
1336                 .proc_handler   = &proc_dointvec_jiffies,
1337                 .strategy       = &sysctl_jiffies,
1338         },
1339 #endif
1340         {
1341                 .ctl_name       = CTL_UNNUMBERED,
1342                 .procname       = "mmap_min_addr",
1343                 .data           = &dac_mmap_min_addr,
1344                 .maxlen         = sizeof(unsigned long),
1345                 .mode           = 0644,
1346                 .proc_handler   = &mmap_min_addr_handler,
1347         },
1348 #ifdef CONFIG_NUMA
1349         {
1350                 .ctl_name       = CTL_UNNUMBERED,
1351                 .procname       = "numa_zonelist_order",
1352                 .data           = &numa_zonelist_order,
1353                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1354                 .mode           = 0644,
1355                 .proc_handler   = &numa_zonelist_order_handler,
1356                 .strategy       = &sysctl_string,
1357         },
1358 #endif
1359 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1360    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1361         {
1362                 .ctl_name       = VM_VDSO_ENABLED,
1363                 .procname       = "vdso_enabled",
1364                 .data           = &vdso_enabled,
1365                 .maxlen         = sizeof(vdso_enabled),
1366                 .mode           = 0644,
1367                 .proc_handler   = &proc_dointvec,
1368                 .strategy       = &sysctl_intvec,
1369                 .extra1         = &zero,
1370         },
1371 #endif
1372 #ifdef CONFIG_HIGHMEM
1373         {
1374                 .ctl_name       = CTL_UNNUMBERED,
1375                 .procname       = "highmem_is_dirtyable",
1376                 .data           = &vm_highmem_is_dirtyable,
1377                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1378                 .mode           = 0644,
1379                 .proc_handler   = &proc_dointvec_minmax,
1380                 .strategy       = &sysctl_intvec,
1381                 .extra1         = &zero,
1382                 .extra2         = &one,
1383         },
1384 #endif
1385         {
1386                 .ctl_name       = CTL_UNNUMBERED,
1387                 .procname       = "scan_unevictable_pages",
1388                 .data           = &scan_unevictable_pages,
1389                 .maxlen         = sizeof(scan_unevictable_pages),
1390                 .mode           = 0644,
1391                 .proc_handler   = &scan_unevictable_handler,
1392         },
1393 /*
1394  * NOTE: do not add new entries to this table unless you have read
1395  * Documentation/sysctl/ctl_unnumbered.txt
1396  */
1397         { .ctl_name = 0 }
1398 };
1399
1400 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1401 static struct ctl_table binfmt_misc_table[] = {
1402         { .ctl_name = 0 }
1403 };
1404 #endif
1405
1406 static struct ctl_table fs_table[] = {
1407         {
1408                 .ctl_name       = FS_NRINODE,
1409                 .procname       = "inode-nr",
1410                 .data           = &inodes_stat,
1411                 .maxlen         = 2*sizeof(int),
1412                 .mode           = 0444,
1413                 .proc_handler   = &proc_dointvec,
1414         },
1415         {
1416                 .ctl_name       = FS_STATINODE,
1417                 .procname       = "inode-state",
1418                 .data           = &inodes_stat,
1419                 .maxlen         = 7*sizeof(int),
1420                 .mode           = 0444,
1421                 .proc_handler   = &proc_dointvec,
1422         },
1423         {
1424                 .procname       = "file-nr",
1425                 .data           = &files_stat,
1426                 .maxlen         = 3*sizeof(int),
1427                 .mode           = 0444,
1428                 .proc_handler   = &proc_nr_files,
1429         },
1430         {
1431                 .ctl_name       = FS_MAXFILE,
1432                 .procname       = "file-max",
1433                 .data           = &files_stat.max_files,
1434                 .maxlen         = sizeof(int),
1435                 .mode           = 0644,
1436                 .proc_handler   = &proc_dointvec,
1437         },
1438         {
1439                 .ctl_name       = CTL_UNNUMBERED,
1440                 .procname       = "nr_open",
1441                 .data           = &sysctl_nr_open,
1442                 .maxlen         = sizeof(int),
1443                 .mode           = 0644,
1444                 .proc_handler   = &proc_dointvec_minmax,
1445                 .extra1         = &sysctl_nr_open_min,
1446                 .extra2         = &sysctl_nr_open_max,
1447         },
1448         {
1449                 .ctl_name       = FS_DENTRY,
1450                 .procname       = "dentry-state",
1451                 .data           = &dentry_stat,
1452                 .maxlen         = 6*sizeof(int),
1453                 .mode           = 0444,
1454                 .proc_handler   = &proc_dointvec,
1455         },
1456         {
1457                 .ctl_name       = FS_OVERFLOWUID,
1458                 .procname       = "overflowuid",
1459                 .data           = &fs_overflowuid,
1460                 .maxlen         = sizeof(int),
1461                 .mode           = 0644,
1462                 .proc_handler   = &proc_dointvec_minmax,
1463                 .strategy       = &sysctl_intvec,
1464                 .extra1         = &minolduid,
1465                 .extra2         = &maxolduid,
1466         },
1467         {
1468                 .ctl_name       = FS_OVERFLOWGID,
1469                 .procname       = "overflowgid",
1470                 .data           = &fs_overflowgid,
1471                 .maxlen         = sizeof(int),
1472                 .mode           = 0644,
1473                 .proc_handler   = &proc_dointvec_minmax,
1474                 .strategy       = &sysctl_intvec,
1475                 .extra1         = &minolduid,
1476                 .extra2         = &maxolduid,
1477         },
1478 #ifdef CONFIG_FILE_LOCKING
1479         {
1480                 .ctl_name       = FS_LEASES,
1481                 .procname       = "leases-enable",
1482                 .data           = &leases_enable,
1483                 .maxlen         = sizeof(int),
1484                 .mode           = 0644,
1485                 .proc_handler   = &proc_dointvec,
1486         },
1487 #endif
1488 #ifdef CONFIG_DNOTIFY
1489         {
1490                 .ctl_name       = FS_DIR_NOTIFY,
1491                 .procname       = "dir-notify-enable",
1492                 .data           = &dir_notify_enable,
1493                 .maxlen         = sizeof(int),
1494                 .mode           = 0644,
1495                 .proc_handler   = &proc_dointvec,
1496         },
1497 #endif
1498 #ifdef CONFIG_MMU
1499 #ifdef CONFIG_FILE_LOCKING
1500         {
1501                 .ctl_name       = FS_LEASE_TIME,
1502                 .procname       = "lease-break-time",
1503                 .data           = &lease_break_time,
1504                 .maxlen         = sizeof(int),
1505                 .mode           = 0644,
1506                 .proc_handler   = &proc_dointvec,
1507         },
1508 #endif
1509 #ifdef CONFIG_AIO
1510         {
1511                 .procname       = "aio-nr",
1512                 .data           = &aio_nr,
1513                 .maxlen         = sizeof(aio_nr),
1514                 .mode           = 0444,
1515                 .proc_handler   = &proc_doulongvec_minmax,
1516         },
1517         {
1518                 .procname       = "aio-max-nr",
1519                 .data           = &aio_max_nr,
1520                 .maxlen         = sizeof(aio_max_nr),
1521                 .mode           = 0644,
1522                 .proc_handler   = &proc_doulongvec_minmax,
1523         },
1524 #endif /* CONFIG_AIO */
1525 #ifdef CONFIG_INOTIFY_USER
1526         {
1527                 .ctl_name       = FS_INOTIFY,
1528                 .procname       = "inotify",
1529                 .mode           = 0555,
1530                 .child          = inotify_table,
1531         },
1532 #endif
1533 #ifdef CONFIG_EPOLL
1534         {
1535                 .procname       = "epoll",
1536                 .mode           = 0555,
1537                 .child          = epoll_table,
1538         },
1539 #endif
1540 #endif
1541         {
1542                 .ctl_name       = KERN_SETUID_DUMPABLE,
1543                 .procname       = "suid_dumpable",
1544                 .data           = &suid_dumpable,
1545                 .maxlen         = sizeof(int),
1546                 .mode           = 0644,
1547                 .proc_handler   = &proc_dointvec_minmax,
1548                 .strategy       = &sysctl_intvec,
1549                 .extra1         = &zero,
1550                 .extra2         = &two,
1551         },
1552 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1553         {
1554                 .ctl_name       = CTL_UNNUMBERED,
1555                 .procname       = "binfmt_misc",
1556                 .mode           = 0555,
1557                 .child          = binfmt_misc_table,
1558         },
1559 #endif
1560 /*
1561  * NOTE: do not add new entries to this table unless you have read
1562  * Documentation/sysctl/ctl_unnumbered.txt
1563  */
1564         { .ctl_name = 0 }
1565 };
1566
1567 static struct ctl_table debug_table[] = {
1568 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1569         {
1570                 .ctl_name       = CTL_UNNUMBERED,
1571                 .procname       = "exception-trace",
1572                 .data           = &show_unhandled_signals,
1573                 .maxlen         = sizeof(int),
1574                 .mode           = 0644,
1575                 .proc_handler   = proc_dointvec
1576         },
1577 #endif
1578         { .ctl_name = 0 }
1579 };
1580
1581 static struct ctl_table dev_table[] = {
1582         { .ctl_name = 0 }
1583 };
1584
1585 static DEFINE_SPINLOCK(sysctl_lock);
1586
1587 /* called under sysctl_lock */
1588 static int use_table(struct ctl_table_header *p)
1589 {
1590         if (unlikely(p->unregistering))
1591                 return 0;
1592         p->used++;
1593         return 1;
1594 }
1595
1596 /* called under sysctl_lock */
1597 static void unuse_table(struct ctl_table_header *p)
1598 {
1599         if (!--p->used)
1600                 if (unlikely(p->unregistering))
1601                         complete(p->unregistering);
1602 }
1603
1604 /* called under sysctl_lock, will reacquire if has to wait */
1605 static void start_unregistering(struct ctl_table_header *p)
1606 {
1607         /*
1608          * if p->used is 0, nobody will ever touch that entry again;
1609          * we'll eliminate all paths to it before dropping sysctl_lock
1610          */
1611         if (unlikely(p->used)) {
1612                 struct completion wait;
1613                 init_completion(&wait);
1614                 p->unregistering = &wait;
1615                 spin_unlock(&sysctl_lock);
1616                 wait_for_completion(&wait);
1617                 spin_lock(&sysctl_lock);
1618         } else {
1619                 /* anything non-NULL; we'll never dereference it */
1620                 p->unregistering = ERR_PTR(-EINVAL);
1621         }
1622         /*
1623          * do not remove from the list until nobody holds it; walking the
1624          * list in do_sysctl() relies on that.
1625          */
1626         list_del_init(&p->ctl_entry);
1627 }
1628
1629 void sysctl_head_get(struct ctl_table_header *head)
1630 {
1631         spin_lock(&sysctl_lock);
1632         head->count++;
1633         spin_unlock(&sysctl_lock);
1634 }
1635
1636 void sysctl_head_put(struct ctl_table_header *head)
1637 {
1638         spin_lock(&sysctl_lock);
1639         if (!--head->count)
1640                 kfree(head);
1641         spin_unlock(&sysctl_lock);
1642 }
1643
1644 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1645 {
1646         if (!head)
1647                 BUG();
1648         spin_lock(&sysctl_lock);
1649         if (!use_table(head))
1650                 head = ERR_PTR(-ENOENT);
1651         spin_unlock(&sysctl_lock);
1652         return head;
1653 }
1654
1655 void sysctl_head_finish(struct ctl_table_header *head)
1656 {
1657         if (!head)
1658                 return;
1659         spin_lock(&sysctl_lock);
1660         unuse_table(head);
1661         spin_unlock(&sysctl_lock);
1662 }
1663
1664 static struct ctl_table_set *
1665 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1666 {
1667         struct ctl_table_set *set = &root->default_set;
1668         if (root->lookup)
1669                 set = root->lookup(root, namespaces);
1670         return set;
1671 }
1672
1673 static struct list_head *
1674 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1675 {
1676         struct ctl_table_set *set = lookup_header_set(root, namespaces);
1677         return &set->list;
1678 }
1679
1680 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1681                                             struct ctl_table_header *prev)
1682 {
1683         struct ctl_table_root *root;
1684         struct list_head *header_list;
1685         struct ctl_table_header *head;
1686         struct list_head *tmp;
1687
1688         spin_lock(&sysctl_lock);
1689         if (prev) {
1690                 head = prev;
1691                 tmp = &prev->ctl_entry;
1692                 unuse_table(prev);
1693                 goto next;
1694         }
1695         tmp = &root_table_header.ctl_entry;
1696         for (;;) {
1697                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1698
1699                 if (!use_table(head))
1700                         goto next;
1701                 spin_unlock(&sysctl_lock);
1702                 return head;
1703         next:
1704                 root = head->root;
1705                 tmp = tmp->next;
1706                 header_list = lookup_header_list(root, namespaces);
1707                 if (tmp != header_list)
1708                         continue;
1709
1710                 do {
1711                         root = list_entry(root->root_list.next,
1712                                         struct ctl_table_root, root_list);
1713                         if (root == &sysctl_table_root)
1714                                 goto out;
1715                         header_list = lookup_header_list(root, namespaces);
1716                 } while (list_empty(header_list));
1717                 tmp = header_list->next;
1718         }
1719 out:
1720         spin_unlock(&sysctl_lock);
1721         return NULL;
1722 }
1723
1724 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1725 {
1726         return __sysctl_head_next(current->nsproxy, prev);
1727 }
1728
1729 void register_sysctl_root(struct ctl_table_root *root)
1730 {
1731         spin_lock(&sysctl_lock);
1732         list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1733         spin_unlock(&sysctl_lock);
1734 }
1735
1736 #ifdef CONFIG_SYSCTL_SYSCALL
1737 /* Perform the actual read/write of a sysctl table entry. */
1738 static int do_sysctl_strategy(struct ctl_table_root *root,
1739                         struct ctl_table *table,
1740                         void __user *oldval, size_t __user *oldlenp,
1741                         void __user *newval, size_t newlen)
1742 {
1743         int op = 0, rc;
1744
1745         if (oldval)
1746                 op |= MAY_READ;
1747         if (newval)
1748                 op |= MAY_WRITE;
1749         if (sysctl_perm(root, table, op))
1750                 return -EPERM;
1751
1752         if (table->strategy) {
1753                 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1754                 if (rc < 0)
1755                         return rc;
1756                 if (rc > 0)
1757                         return 0;
1758         }
1759
1760         /* If there is no strategy routine, or if the strategy returns
1761          * zero, proceed with automatic r/w */
1762         if (table->data && table->maxlen) {
1763                 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1764                 if (rc < 0)
1765                         return rc;
1766         }
1767         return 0;
1768 }
1769
1770 static int parse_table(int __user *name, int nlen,
1771                        void __user *oldval, size_t __user *oldlenp,
1772                        void __user *newval, size_t newlen,
1773                        struct ctl_table_root *root,
1774                        struct ctl_table *table)
1775 {
1776         int n;
1777 repeat:
1778         if (!nlen)
1779                 return -ENOTDIR;
1780         if (get_user(n, name))
1781                 return -EFAULT;
1782         for ( ; table->ctl_name || table->procname; table++) {
1783                 if (!table->ctl_name)
1784                         continue;
1785                 if (n == table->ctl_name) {
1786                         int error;
1787                         if (table->child) {
1788                                 if (sysctl_perm(root, table, MAY_EXEC))
1789                                         return -EPERM;
1790                                 name++;
1791                                 nlen--;
1792                                 table = table->child;
1793                                 goto repeat;
1794                         }
1795                         error = do_sysctl_strategy(root, table,
1796                                                    oldval, oldlenp,
1797                                                    newval, newlen);
1798                         return error;
1799                 }
1800         }
1801         return -ENOTDIR;
1802 }
1803
1804 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1805                void __user *newval, size_t newlen)
1806 {
1807         struct ctl_table_header *head;
1808         int error = -ENOTDIR;
1809
1810         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1811                 return -ENOTDIR;
1812         if (oldval) {
1813                 int old_len;
1814                 if (!oldlenp || get_user(old_len, oldlenp))
1815                         return -EFAULT;
1816         }
1817
1818         for (head = sysctl_head_next(NULL); head;
1819                         head = sysctl_head_next(head)) {
1820                 error = parse_table(name, nlen, oldval, oldlenp,
1821                                         newval, newlen,
1822                                         head->root, head->ctl_table);
1823                 if (error != -ENOTDIR) {
1824                         sysctl_head_finish(head);
1825                         break;
1826                 }
1827         }
1828         return error;
1829 }
1830
1831 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1832 {
1833         struct __sysctl_args tmp;
1834         int error;
1835
1836         if (copy_from_user(&tmp, args, sizeof(tmp)))
1837                 return -EFAULT;
1838
1839         error = deprecated_sysctl_warning(&tmp);
1840         if (error)
1841                 goto out;
1842
1843         lock_kernel();
1844         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1845                           tmp.newval, tmp.newlen);
1846         unlock_kernel();
1847 out:
1848         return error;
1849 }
1850 #endif /* CONFIG_SYSCTL_SYSCALL */
1851
1852 /*
1853  * sysctl_perm does NOT grant the superuser all rights automatically, because
1854  * some sysctl variables are readonly even to root.
1855  */
1856
1857 static int test_perm(int mode, int op)
1858 {
1859         if (!current_euid())
1860                 mode >>= 6;
1861         else if (in_egroup_p(0))
1862                 mode >>= 3;
1863         if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1864                 return 0;
1865         return -EACCES;
1866 }
1867
1868 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1869 {
1870         int error;
1871         int mode;
1872
1873         error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1874         if (error)
1875                 return error;
1876
1877         if (root->permissions)
1878                 mode = root->permissions(root, current->nsproxy, table);
1879         else
1880                 mode = table->mode;
1881
1882         return test_perm(mode, op);
1883 }
1884
1885 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1886 {
1887         for (; table->ctl_name || table->procname; table++) {
1888                 table->parent = parent;
1889                 if (table->child)
1890                         sysctl_set_parent(table, table->child);
1891         }
1892 }
1893
1894 static __init int sysctl_init(void)
1895 {
1896         sysctl_set_parent(NULL, root_table);
1897 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1898         {
1899                 int err;
1900                 err = sysctl_check_table(current->nsproxy, root_table);
1901         }
1902 #endif
1903         return 0;
1904 }
1905
1906 core_initcall(sysctl_init);
1907
1908 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1909                                       struct ctl_table *table)
1910 {
1911         struct ctl_table *p;
1912         const char *s = branch->procname;
1913
1914         /* branch should have named subdirectory as its first element */
1915         if (!s || !branch->child)
1916                 return NULL;
1917
1918         /* ... and nothing else */
1919         if (branch[1].procname || branch[1].ctl_name)
1920                 return NULL;
1921
1922         /* table should contain subdirectory with the same name */
1923         for (p = table; p->procname || p->ctl_name; p++) {
1924                 if (!p->child)
1925                         continue;
1926                 if (p->procname && strcmp(p->procname, s) == 0)
1927                         return p;
1928         }
1929         return NULL;
1930 }
1931
1932 /* see if attaching q to p would be an improvement */
1933 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1934 {
1935         struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1936         struct ctl_table *next;
1937         int is_better = 0;
1938         int not_in_parent = !p->attached_by;
1939
1940         while ((next = is_branch_in(by, to)) != NULL) {
1941                 if (by == q->attached_by)
1942                         is_better = 1;
1943                 if (to == p->attached_by)
1944                         not_in_parent = 1;
1945                 by = by->child;
1946                 to = next->child;
1947         }
1948
1949         if (is_better && not_in_parent) {
1950                 q->attached_by = by;
1951                 q->attached_to = to;
1952                 q->parent = p;
1953         }
1954 }
1955
1956 /**
1957  * __register_sysctl_paths - register a sysctl hierarchy
1958  * @root: List of sysctl headers to register on
1959  * @namespaces: Data to compute which lists of sysctl entries are visible
1960  * @path: The path to the directory the sysctl table is in.
1961  * @table: the top-level table structure
1962  *
1963  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1964  * array. A completely 0 filled entry terminates the table.
1965  *
1966  * The members of the &struct ctl_table structure are used as follows:
1967  *
1968  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1969  *            must be unique within that level of sysctl
1970  *
1971  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1972  *            enter a sysctl file
1973  *
1974  * data - a pointer to data for use by proc_handler
1975  *
1976  * maxlen - the maximum size in bytes of the data
1977  *
1978  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1979  *
1980  * child - a pointer to the child sysctl table if this entry is a directory, or
1981  *         %NULL.
1982  *
1983  * proc_handler - the text handler routine (described below)
1984  *
1985  * strategy - the strategy routine (described below)
1986  *
1987  * de - for internal use by the sysctl routines
1988  *
1989  * extra1, extra2 - extra pointers usable by the proc handler routines
1990  *
1991  * Leaf nodes in the sysctl tree will be represented by a single file
1992  * under /proc; non-leaf nodes will be represented by directories.
1993  *
1994  * sysctl(2) can automatically manage read and write requests through
1995  * the sysctl table.  The data and maxlen fields of the ctl_table
1996  * struct enable minimal validation of the values being written to be
1997  * performed, and the mode field allows minimal authentication.
1998  *
1999  * More sophisticated management can be enabled by the provision of a
2000  * strategy routine with the table entry.  This will be called before
2001  * any automatic read or write of the data is performed.
2002  *
2003  * The strategy routine may return
2004  *
2005  * < 0 - Error occurred (error is passed to user process)
2006  *
2007  * 0   - OK - proceed with automatic read or write.
2008  *
2009  * > 0 - OK - read or write has been done by the strategy routine, so
2010  *       return immediately.
2011  *
2012  * There must be a proc_handler routine for any terminal nodes
2013  * mirrored under /proc/sys (non-terminals are handled by a built-in
2014  * directory handler).  Several default handlers are available to
2015  * cover common cases -
2016  *
2017  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
2018  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
2019  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
2020  *
2021  * It is the handler's job to read the input buffer from user memory
2022  * and process it. The handler should return 0 on success.
2023  *
2024  * This routine returns %NULL on a failure to register, and a pointer
2025  * to the table header on success.
2026  */
2027 struct ctl_table_header *__register_sysctl_paths(
2028         struct ctl_table_root *root,
2029         struct nsproxy *namespaces,
2030         const struct ctl_path *path, struct ctl_table *table)
2031 {
2032         struct ctl_table_header *header;
2033         struct ctl_table *new, **prevp;
2034         unsigned int n, npath;
2035         struct ctl_table_set *set;
2036
2037         /* Count the path components */
2038         for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
2039                 ;
2040
2041         /*
2042          * For each path component, allocate a 2-element ctl_table array.
2043          * The first array element will be filled with the sysctl entry
2044          * for this, the second will be the sentinel (ctl_name == 0).
2045          *
2046          * We allocate everything in one go so that we don't have to
2047          * worry about freeing additional memory in unregister_sysctl_table.
2048          */
2049         header = kzalloc(sizeof(struct ctl_table_header) +
2050                          (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
2051         if (!header)
2052                 return NULL;
2053
2054         new = (struct ctl_table *) (header + 1);
2055
2056         /* Now connect the dots */
2057         prevp = &header->ctl_table;
2058         for (n = 0; n < npath; ++n, ++path) {
2059                 /* Copy the procname */
2060                 new->procname = path->procname;
2061                 new->ctl_name = path->ctl_name;
2062                 new->mode     = 0555;
2063
2064                 *prevp = new;
2065                 prevp = &new->child;
2066
2067                 new += 2;
2068         }
2069         *prevp = table;
2070         header->ctl_table_arg = table;
2071
2072         INIT_LIST_HEAD(&header->ctl_entry);
2073         header->used = 0;
2074         header->unregistering = NULL;
2075         header->root = root;
2076         sysctl_set_parent(NULL, header->ctl_table);
2077         header->count = 1;
2078 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2079         if (sysctl_check_table(namespaces, header->ctl_table)) {
2080                 kfree(header);
2081                 return NULL;
2082         }
2083 #endif
2084         spin_lock(&sysctl_lock);
2085         header->set = lookup_header_set(root, namespaces);
2086         header->attached_by = header->ctl_table;
2087         header->attached_to = root_table;
2088         header->parent = &root_table_header;
2089         for (set = header->set; set; set = set->parent) {
2090                 struct ctl_table_header *p;
2091                 list_for_each_entry(p, &set->list, ctl_entry) {
2092                         if (p->unregistering)
2093                                 continue;
2094                         try_attach(p, header);
2095                 }
2096         }
2097         header->parent->count++;
2098         list_add_tail(&header->ctl_entry, &header->set->list);
2099         spin_unlock(&sysctl_lock);
2100
2101         return header;
2102 }
2103
2104 /**
2105  * register_sysctl_table_path - register a sysctl table hierarchy
2106  * @path: The path to the directory the sysctl table is in.
2107  * @table: the top-level table structure
2108  *
2109  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2110  * array. A completely 0 filled entry terminates the table.
2111  *
2112  * See __register_sysctl_paths for more details.
2113  */
2114 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2115                                                 struct ctl_table *table)
2116 {
2117         return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2118                                         path, table);
2119 }
2120
2121 /**
2122  * register_sysctl_table - register a sysctl table hierarchy
2123  * @table: the top-level table structure
2124  *
2125  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2126  * array. A completely 0 filled entry terminates the table.
2127  *
2128  * See register_sysctl_paths for more details.
2129  */
2130 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2131 {
2132         static const struct ctl_path null_path[] = { {} };
2133
2134         return register_sysctl_paths(null_path, table);
2135 }
2136
2137 /**
2138  * unregister_sysctl_table - unregister a sysctl table hierarchy
2139  * @header: the header returned from register_sysctl_table
2140  *
2141  * Unregisters the sysctl table and all children. proc entries may not
2142  * actually be removed until they are no longer used by anyone.
2143  */
2144 void unregister_sysctl_table(struct ctl_table_header * header)
2145 {
2146         might_sleep();
2147
2148         if (header == NULL)
2149                 return;
2150
2151         spin_lock(&sysctl_lock);
2152         start_unregistering(header);
2153         if (!--header->parent->count) {
2154                 WARN_ON(1);
2155                 kfree(header->parent);
2156         }
2157         if (!--header->count)
2158                 kfree(header);
2159         spin_unlock(&sysctl_lock);
2160 }
2161
2162 int sysctl_is_seen(struct ctl_table_header *p)
2163 {
2164         struct ctl_table_set *set = p->set;
2165         int res;
2166         spin_lock(&sysctl_lock);
2167         if (p->unregistering)
2168                 res = 0;
2169         else if (!set->is_seen)
2170                 res = 1;
2171         else
2172                 res = set->is_seen(set);
2173         spin_unlock(&sysctl_lock);
2174         return res;
2175 }
2176
2177 void setup_sysctl_set(struct ctl_table_set *p,
2178         struct ctl_table_set *parent,
2179         int (*is_seen)(struct ctl_table_set *))
2180 {
2181         INIT_LIST_HEAD(&p->list);
2182         p->parent = parent ? parent : &sysctl_table_root.default_set;
2183         p->is_seen = is_seen;
2184 }
2185
2186 #else /* !CONFIG_SYSCTL */
2187 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2188 {
2189         return NULL;
2190 }
2191
2192 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2193                                                     struct ctl_table *table)
2194 {
2195         return NULL;
2196 }
2197
2198 void unregister_sysctl_table(struct ctl_table_header * table)
2199 {
2200 }
2201
2202 void setup_sysctl_set(struct ctl_table_set *p,
2203         struct ctl_table_set *parent,
2204         int (*is_seen)(struct ctl_table_set *))
2205 {
2206 }
2207
2208 void sysctl_head_put(struct ctl_table_header *head)
2209 {
2210 }
2211
2212 #endif /* CONFIG_SYSCTL */
2213
2214 /*
2215  * /proc/sys support
2216  */
2217
2218 #ifdef CONFIG_PROC_SYSCTL
2219
2220 static int _proc_do_string(void* data, int maxlen, int write,
2221                            struct file *filp, void __user *buffer,
2222                            size_t *lenp, loff_t *ppos)
2223 {
2224         size_t len;
2225         char __user *p;
2226         char c;
2227
2228         if (!data || !maxlen || !*lenp) {
2229                 *lenp = 0;
2230                 return 0;
2231         }
2232
2233         if (write) {
2234                 len = 0;
2235                 p = buffer;
2236                 while (len < *lenp) {
2237                         if (get_user(c, p++))
2238                                 return -EFAULT;
2239                         if (c == 0 || c == '\n')
2240                                 break;
2241                         len++;
2242                 }
2243                 if (len >= maxlen)
2244                         len = maxlen-1;
2245                 if(copy_from_user(data, buffer, len))
2246                         return -EFAULT;
2247                 ((char *) data)[len] = 0;
2248                 *ppos += *lenp;
2249         } else {
2250                 len = strlen(data);
2251                 if (len > maxlen)
2252                         len = maxlen;
2253
2254                 if (*ppos > len) {
2255                         *lenp = 0;
2256                         return 0;
2257                 }
2258
2259                 data += *ppos;
2260                 len  -= *ppos;
2261
2262                 if (len > *lenp)
2263                         len = *lenp;
2264                 if (len)
2265                         if(copy_to_user(buffer, data, len))
2266                                 return -EFAULT;
2267                 if (len < *lenp) {
2268                         if(put_user('\n', ((char __user *) buffer) + len))
2269                                 return -EFAULT;
2270                         len++;
2271                 }
2272                 *lenp = len;
2273                 *ppos += len;
2274         }
2275         return 0;
2276 }
2277
2278 /**
2279  * proc_dostring - read a string sysctl
2280  * @table: the sysctl table
2281  * @write: %TRUE if this is a write to the sysctl file
2282  * @filp: the file structure
2283  * @buffer: the user buffer
2284  * @lenp: the size of the user buffer
2285  * @ppos: file position
2286  *
2287  * Reads/writes a string from/to the user buffer. If the kernel
2288  * buffer provided is not large enough to hold the string, the
2289  * string is truncated. The copied string is %NULL-terminated.
2290  * If the string is being read by the user process, it is copied
2291  * and a newline '\n' is added. It is truncated if the buffer is
2292  * not large enough.
2293  *
2294  * Returns 0 on success.
2295  */
2296 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2297                   void __user *buffer, size_t *lenp, loff_t *ppos)
2298 {
2299         return _proc_do_string(table->data, table->maxlen, write, filp,
2300                                buffer, lenp, ppos);
2301 }
2302
2303
2304 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2305                                  int *valp,
2306                                  int write, void *data)
2307 {
2308         if (write) {
2309                 *valp = *negp ? -*lvalp : *lvalp;
2310         } else {
2311                 int val = *valp;
2312                 if (val < 0) {
2313                         *negp = -1;
2314                         *lvalp = (unsigned long)-val;
2315                 } else {
2316                         *negp = 0;
2317                         *lvalp = (unsigned long)val;
2318                 }
2319         }
2320         return 0;
2321 }
2322
2323 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2324                   int write, struct file *filp, void __user *buffer,
2325                   size_t *lenp, loff_t *ppos,
2326                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2327                               int write, void *data),
2328                   void *data)
2329 {
2330 #define TMPBUFLEN 21
2331         int *i, vleft, first = 1, neg;
2332         unsigned long lval;
2333         size_t left, len;
2334
2335         char buf[TMPBUFLEN], *p;
2336         char __user *s = buffer;
2337
2338         if (!tbl_data || !table->maxlen || !*lenp ||
2339             (*ppos && !write)) {
2340                 *lenp = 0;
2341                 return 0;
2342         }
2343
2344         i = (int *) tbl_data;
2345         vleft = table->maxlen / sizeof(*i);
2346         left = *lenp;
2347
2348         if (!conv)
2349                 conv = do_proc_dointvec_conv;
2350
2351         for (; left && vleft--; i++, first=0) {
2352                 if (write) {
2353                         while (left) {
2354                                 char c;
2355                                 if (get_user(c, s))
2356                                         return -EFAULT;
2357                                 if (!isspace(c))
2358                                         break;
2359                                 left--;
2360                                 s++;
2361                         }
2362                         if (!left)
2363                                 break;
2364                         neg = 0;
2365                         len = left;
2366                         if (len > sizeof(buf) - 1)
2367                                 len = sizeof(buf) - 1;
2368                         if (copy_from_user(buf, s, len))
2369                                 return -EFAULT;
2370                         buf[len] = 0;
2371                         p = buf;
2372                         if (*p == '-' && left > 1) {
2373                                 neg = 1;
2374                                 p++;
2375                         }
2376                         if (*p < '0' || *p > '9')
2377                                 break;
2378
2379                         lval = simple_strtoul(p, &p, 0);
2380
2381                         len = p-buf;
2382                         if ((len < left) && *p && !isspace(*p))
2383                                 break;
2384                         s += len;
2385                         left -= len;
2386
2387                         if (conv(&neg, &lval, i, 1, data))
2388                                 break;
2389                 } else {
2390                         p = buf;
2391                         if (!first)
2392                                 *p++ = '\t';
2393
2394                         if (conv(&neg, &lval, i, 0, data))
2395                                 break;
2396
2397                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
2398                         len = strlen(buf);
2399                         if (len > left)
2400                                 len = left;
2401                         if(copy_to_user(s, buf, len))
2402                                 return -EFAULT;
2403                         left -= len;
2404                         s += len;
2405                 }
2406         }
2407
2408         if (!write && !first && left) {
2409                 if(put_user('\n', s))
2410                         return -EFAULT;
2411                 left--, s++;
2412         }
2413         if (write) {
2414                 while (left) {
2415                         char c;
2416                         if (get_user(c, s++))
2417                                 return -EFAULT;
2418                         if (!isspace(c))
2419                                 break;
2420                         left--;
2421                 }
2422         }
2423         if (write && first)
2424                 return -EINVAL;
2425         *lenp -= left;
2426         *ppos += *lenp;
2427         return 0;
2428 #undef TMPBUFLEN
2429 }
2430
2431 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2432                   void __user *buffer, size_t *lenp, loff_t *ppos,
2433                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2434                               int write, void *data),
2435                   void *data)
2436 {
2437         return __do_proc_dointvec(table->data, table, write, filp,
2438                         buffer, lenp, ppos, conv, data);
2439 }
2440
2441 /**
2442  * proc_dointvec - read a vector of integers
2443  * @table: the sysctl table
2444  * @write: %TRUE if this is a write to the sysctl file
2445  * @filp: the file structure
2446  * @buffer: the user buffer
2447  * @lenp: the size of the user buffer
2448  * @ppos: file position
2449  *
2450  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2451  * values from/to the user buffer, treated as an ASCII string.
2452  *
2453  * Returns 0 on success.
2454  */
2455 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2456                      void __user *buffer, size_t *lenp, loff_t *ppos)
2457 {
2458     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2459                             NULL,NULL);
2460 }
2461
2462 /*
2463  * Taint values can only be increased
2464  * This means we can safely use a temporary.
2465  */
2466 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2467                                void __user *buffer, size_t *lenp, loff_t *ppos)
2468 {
2469         struct ctl_table t;
2470         unsigned long tmptaint = get_taint();
2471         int err;
2472
2473         if (write && !capable(CAP_SYS_ADMIN))
2474                 return -EPERM;
2475
2476         t = *table;
2477         t.data = &tmptaint;
2478         err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2479         if (err < 0)
2480                 return err;
2481
2482         if (write) {
2483                 /*
2484                  * Poor man's atomic or. Not worth adding a primitive
2485                  * to everyone's atomic.h for this
2486                  */
2487                 int i;
2488                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2489                         if ((tmptaint >> i) & 1)
2490                                 add_taint(i);
2491                 }
2492         }
2493
2494         return err;
2495 }
2496
2497 struct do_proc_dointvec_minmax_conv_param {
2498         int *min;
2499         int *max;
2500 };
2501
2502 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2503                                         int *valp,
2504                                         int write, void *data)
2505 {
2506         struct do_proc_dointvec_minmax_conv_param *param = data;
2507         if (write) {
2508                 int val = *negp ? -*lvalp : *lvalp;
2509                 if ((param->min && *param->min > val) ||
2510                     (param->max && *param->max < val))
2511                         return -EINVAL;
2512                 *valp = val;
2513         } else {
2514                 int val = *valp;
2515                 if (val < 0) {
2516                         *negp = -1;
2517                         *lvalp = (unsigned long)-val;
2518                 } else {
2519                         *negp = 0;
2520                         *lvalp = (unsigned long)val;
2521                 }
2522         }
2523         return 0;
2524 }
2525
2526 /**
2527  * proc_dointvec_minmax - read a vector of integers with min/max values
2528  * @table: the sysctl table
2529  * @write: %TRUE if this is a write to the sysctl file
2530  * @filp: the file structure
2531  * @buffer: the user buffer
2532  * @lenp: the size of the user buffer
2533  * @ppos: file position
2534  *
2535  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2536  * values from/to the user buffer, treated as an ASCII string.
2537  *
2538  * This routine will ensure the values are within the range specified by
2539  * table->extra1 (min) and table->extra2 (max).
2540  *
2541  * Returns 0 on success.
2542  */
2543 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2544                   void __user *buffer, size_t *lenp, loff_t *ppos)
2545 {
2546         struct do_proc_dointvec_minmax_conv_param param = {
2547                 .min = (int *) table->extra1,
2548                 .max = (int *) table->extra2,
2549         };
2550         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2551                                 do_proc_dointvec_minmax_conv, &param);
2552 }
2553
2554 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2555                                      struct file *filp,
2556                                      void __user *buffer,
2557                                      size_t *lenp, loff_t *ppos,
2558                                      unsigned long convmul,
2559                                      unsigned long convdiv)
2560 {
2561 #define TMPBUFLEN 21
2562         unsigned long *i, *min, *max, val;
2563         int vleft, first=1, neg;
2564         size_t len, left;
2565         char buf[TMPBUFLEN], *p;
2566         char __user *s = buffer;
2567
2568         if (!data || !table->maxlen || !*lenp ||
2569             (*ppos && !write)) {
2570                 *lenp = 0;
2571                 return 0;
2572         }
2573
2574         i = (unsigned long *) data;
2575         min = (unsigned long *) table->extra1;
2576         max = (unsigned long *) table->extra2;
2577         vleft = table->maxlen / sizeof(unsigned long);
2578         left = *lenp;
2579
2580         for (; left && vleft--; i++, min++, max++, first=0) {
2581                 if (write) {
2582                         while (left) {
2583                                 char c;
2584                                 if (get_user(c, s))
2585                                         return -EFAULT;
2586                                 if (!isspace(c))
2587                                         break;
2588                                 left--;
2589                                 s++;
2590                         }
2591                         if (!left)
2592                                 break;
2593                         neg = 0;
2594                         len = left;
2595                         if (len > TMPBUFLEN-1)
2596                                 len = TMPBUFLEN-1;
2597                         if (copy_from_user(buf, s, len))
2598                                 return -EFAULT;
2599                         buf[len] = 0;
2600                         p = buf;
2601                         if (*p == '-' && left > 1) {
2602                                 neg = 1;
2603                                 p++;
2604                         }
2605                         if (*p < '0' || *p > '9')
2606                                 break;
2607                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2608                         len = p-buf;
2609                         if ((len < left) && *p && !isspace(*p))
2610                                 break;
2611                         if (neg)
2612                                 val = -val;
2613                         s += len;
2614                         left -= len;
2615
2616                         if(neg)
2617                                 continue;
2618                         if ((min && val < *min) || (max && val > *max))
2619                                 continue;
2620                         *i = val;
2621                 } else {
2622                         p = buf;
2623                         if (!first)
2624                                 *p++ = '\t';
2625                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2626                         len = strlen(buf);
2627                         if (len > left)
2628                                 len = left;
2629                         if(copy_to_user(s, buf, len))
2630                                 return -EFAULT;
2631                         left -= len;
2632                         s += len;
2633                 }
2634         }
2635
2636         if (!write && !first && left) {
2637                 if(put_user('\n', s))
2638                         return -EFAULT;
2639                 left--, s++;
2640         }
2641         if (write) {
2642                 while (left) {
2643                         char c;
2644                         if (get_user(c, s++))
2645                                 return -EFAULT;
2646                         if (!isspace(c))
2647                                 break;
2648                         left--;
2649                 }
2650         }
2651         if (write && first)
2652                 return -EINVAL;
2653         *lenp -= left;
2654         *ppos += *lenp;
2655         return 0;
2656 #undef TMPBUFLEN
2657 }
2658
2659 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2660                                      struct file *filp,
2661                                      void __user *buffer,
2662                                      size_t *lenp, loff_t *ppos,
2663                                      unsigned long convmul,
2664                                      unsigned long convdiv)
2665 {
2666         return __do_proc_doulongvec_minmax(table->data, table, write,
2667                         filp, buffer, lenp, ppos, convmul, convdiv);
2668 }
2669
2670 /**
2671  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2672  * @table: the sysctl table
2673  * @write: %TRUE if this is a write to the sysctl file
2674  * @filp: the file structure
2675  * @buffer: the user buffer
2676  * @lenp: the size of the user buffer
2677  * @ppos: file position
2678  *
2679  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2680  * values from/to the user buffer, treated as an ASCII string.
2681  *
2682  * This routine will ensure the values are within the range specified by
2683  * table->extra1 (min) and table->extra2 (max).
2684  *
2685  * Returns 0 on success.
2686  */
2687 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2688                            void __user *buffer, size_t *lenp, loff_t *ppos)
2689 {
2690     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2691 }
2692
2693 /**
2694  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2695  * @table: the sysctl table
2696  * @write: %TRUE if this is a write to the sysctl file
2697  * @filp: the file structure
2698  * @buffer: the user buffer
2699  * @lenp: the size of the user buffer
2700  * @ppos: file position
2701  *
2702  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2703  * values from/to the user buffer, treated as an ASCII string. The values
2704  * are treated as milliseconds, and converted to jiffies when they are stored.
2705  *
2706  * This routine will ensure the values are within the range specified by
2707  * table->extra1 (min) and table->extra2 (max).
2708  *
2709  * Returns 0 on success.
2710  */
2711 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2712                                       struct file *filp,
2713                                       void __user *buffer,
2714                                       size_t *lenp, loff_t *ppos)
2715 {
2716     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2717                                      lenp, ppos, HZ, 1000l);
2718 }
2719
2720
2721 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2722                                          int *valp,
2723                                          int write, void *data)
2724 {
2725         if (write) {
2726                 if (*lvalp > LONG_MAX / HZ)
2727                         return 1;
2728                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2729         } else {
2730                 int val = *valp;
2731                 unsigned long lval;
2732                 if (val < 0) {
2733                         *negp = -1;
2734                         lval = (unsigned long)-val;
2735                 } else {
2736                         *negp = 0;
2737                         lval = (unsigned long)val;
2738                 }
2739                 *lvalp = lval / HZ;
2740         }
2741         return 0;
2742 }
2743
2744 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2745                                                 int *valp,
2746                                                 int write, void *data)
2747 {
2748         if (write) {
2749                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2750                         return 1;
2751                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2752         } else {
2753                 int val = *valp;
2754                 unsigned long lval;
2755                 if (val < 0) {
2756                         *negp = -1;
2757                         lval = (unsigned long)-val;
2758                 } else {
2759                         *negp = 0;
2760                         lval = (unsigned long)val;
2761                 }
2762                 *lvalp = jiffies_to_clock_t(lval);
2763         }
2764         return 0;
2765 }
2766
2767 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2768                                             int *valp,
2769                                             int write, void *data)
2770 {
2771         if (write) {
2772                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2773         } else {
2774                 int val = *valp;
2775                 unsigned long lval;
2776                 if (val < 0) {
2777                         *negp = -1;
2778                         lval = (unsigned long)-val;
2779                 } else {
2780                         *negp = 0;
2781                         lval = (unsigned long)val;
2782                 }
2783                 *lvalp = jiffies_to_msecs(lval);
2784         }
2785         return 0;
2786 }
2787
2788 /**
2789  * proc_dointvec_jiffies - read a vector of integers as seconds
2790  * @table: the sysctl table
2791  * @write: %TRUE if this is a write to the sysctl file
2792  * @filp: the file structure
2793  * @buffer: the user buffer
2794  * @lenp: the size of the user buffer
2795  * @ppos: file position
2796  *
2797  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2798  * values from/to the user buffer, treated as an ASCII string.
2799  * The values read are assumed to be in seconds, and are converted into
2800  * jiffies.
2801  *
2802  * Returns 0 on success.
2803  */
2804 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2805                           void __user *buffer, size_t *lenp, loff_t *ppos)
2806 {
2807     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2808                             do_proc_dointvec_jiffies_conv,NULL);
2809 }
2810
2811 /**
2812  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2813  * @table: the sysctl table
2814  * @write: %TRUE if this is a write to the sysctl file
2815  * @filp: the file structure
2816  * @buffer: the user buffer
2817  * @lenp: the size of the user buffer
2818  * @ppos: pointer to the file position
2819  *
2820  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2821  * values from/to the user buffer, treated as an ASCII string.
2822  * The values read are assumed to be in 1/USER_HZ seconds, and
2823  * are converted into jiffies.
2824  *
2825  * Returns 0 on success.
2826  */
2827 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2828                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2829 {
2830     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2831                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2832 }
2833
2834 /**
2835  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2836  * @table: the sysctl table
2837  * @write: %TRUE if this is a write to the sysctl file
2838  * @filp: the file structure
2839  * @buffer: the user buffer
2840  * @lenp: the size of the user buffer
2841  * @ppos: file position
2842  * @ppos: the current position in the file
2843  *
2844  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2845  * values from/to the user buffer, treated as an ASCII string.
2846  * The values read are assumed to be in 1/1000 seconds, and
2847  * are converted into jiffies.
2848  *
2849  * Returns 0 on success.
2850  */
2851 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2852                              void __user *buffer, size_t *lenp, loff_t *ppos)
2853 {
2854         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2855                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2856 }
2857
2858 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2859                            void __user *buffer, size_t *lenp, loff_t *ppos)
2860 {
2861         struct pid *new_pid;
2862         pid_t tmp;
2863         int r;
2864
2865         tmp = pid_vnr(cad_pid);
2866
2867         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2868                                lenp, ppos, NULL, NULL);
2869         if (r || !write)
2870                 return r;
2871
2872         new_pid = find_get_pid(tmp);
2873         if (!new_pid)
2874                 return -ESRCH;
2875
2876         put_pid(xchg(&cad_pid, new_pid));
2877         return 0;
2878 }
2879
2880 #else /* CONFIG_PROC_FS */
2881
2882 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2883                   void __user *buffer, size_t *lenp, loff_t *ppos)
2884 {
2885         return -ENOSYS;
2886 }
2887
2888 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2889                   void __user *buffer, size_t *lenp, loff_t *ppos)
2890 {
2891         return -ENOSYS;
2892 }
2893
2894 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2895                     void __user *buffer, size_t *lenp, loff_t *ppos)
2896 {
2897         return -ENOSYS;
2898 }
2899
2900 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2901                     void __user *buffer, size_t *lenp, loff_t *ppos)
2902 {
2903         return -ENOSYS;
2904 }
2905
2906 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2907                     void __user *buffer, size_t *lenp, loff_t *ppos)
2908 {
2909         return -ENOSYS;
2910 }
2911
2912 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2913                              void __user *buffer, size_t *lenp, loff_t *ppos)
2914 {
2915         return -ENOSYS;
2916 }
2917
2918 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2919                     void __user *buffer, size_t *lenp, loff_t *ppos)
2920 {
2921         return -ENOSYS;
2922 }
2923
2924 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2925                                       struct file *filp,
2926                                       void __user *buffer,
2927                                       size_t *lenp, loff_t *ppos)
2928 {
2929     return -ENOSYS;
2930 }
2931
2932
2933 #endif /* CONFIG_PROC_FS */
2934
2935
2936 #ifdef CONFIG_SYSCTL_SYSCALL
2937 /*
2938  * General sysctl support routines
2939  */
2940
2941 /* The generic sysctl data routine (used if no strategy routine supplied) */
2942 int sysctl_data(struct ctl_table *table,
2943                 void __user *oldval, size_t __user *oldlenp,
2944                 void __user *newval, size_t newlen)
2945 {
2946         size_t len;
2947
2948         /* Get out of I don't have a variable */
2949         if (!table->data || !table->maxlen)
2950                 return -ENOTDIR;
2951
2952         if (oldval && oldlenp) {
2953                 if (get_user(len, oldlenp))
2954                         return -EFAULT;
2955                 if (len) {
2956                         if (len > table->maxlen)
2957                                 len = table->maxlen;
2958                         if (copy_to_user(oldval, table->data, len))
2959                                 return -EFAULT;
2960                         if (put_user(len, oldlenp))
2961                                 return -EFAULT;
2962                 }
2963         }
2964
2965         if (newval && newlen) {
2966                 if (newlen > table->maxlen)
2967                         newlen = table->maxlen;
2968
2969                 if (copy_from_user(table->data, newval, newlen))
2970                         return -EFAULT;
2971         }
2972         return 1;
2973 }
2974
2975 /* The generic string strategy routine: */
2976 int sysctl_string(struct ctl_table *table,
2977                   void __user *oldval, size_t __user *oldlenp,
2978                   void __user *newval, size_t newlen)
2979 {
2980         if (!table->data || !table->maxlen)
2981                 return -ENOTDIR;
2982
2983         if (oldval && oldlenp) {
2984                 size_t bufsize;
2985                 if (get_user(bufsize, oldlenp))
2986                         return -EFAULT;
2987                 if (bufsize) {
2988                         size_t len = strlen(table->data), copied;
2989
2990                         /* This shouldn't trigger for a well-formed sysctl */
2991                         if (len > table->maxlen)
2992                                 len = table->maxlen;
2993
2994                         /* Copy up to a max of bufsize-1 bytes of the string */
2995                         copied = (len >= bufsize) ? bufsize - 1 : len;
2996
2997                         if (copy_to_user(oldval, table->data, copied) ||
2998                             put_user(0, (char __user *)(oldval + copied)))
2999                                 return -EFAULT;
3000                         if (put_user(len, oldlenp))
3001                                 return -EFAULT;
3002                 }
3003         }
3004         if (newval && newlen) {
3005                 size_t len = newlen;
3006                 if (len > table->maxlen)
3007                         len = table->maxlen;
3008                 if(copy_from_user(table->data, newval, len))
3009                         return -EFAULT;
3010                 if (len == table->maxlen)
3011                         len--;
3012                 ((char *) table->data)[len] = 0;
3013         }
3014         return 1;
3015 }
3016
3017 /*
3018  * This function makes sure that all of the integers in the vector
3019  * are between the minimum and maximum values given in the arrays
3020  * table->extra1 and table->extra2, respectively.
3021  */
3022 int sysctl_intvec(struct ctl_table *table,
3023                 void __user *oldval, size_t __user *oldlenp,
3024                 void __user *newval, size_t newlen)
3025 {
3026
3027         if (newval && newlen) {
3028                 int __user *vec = (int __user *) newval;
3029                 int *min = (int *) table->extra1;
3030                 int *max = (int *) table->extra2;
3031                 size_t length;
3032                 int i;
3033
3034                 if (newlen % sizeof(int) != 0)
3035                         return -EINVAL;
3036
3037                 if (!table->extra1 && !table->extra2)
3038                         return 0;
3039
3040                 if (newlen > table->maxlen)
3041                         newlen = table->maxlen;
3042                 length = newlen / sizeof(int);
3043
3044                 for (i = 0; i < length; i++) {
3045                         int value;
3046                         if (get_user(value, vec + i))
3047                                 return -EFAULT;
3048                         if (min && value < min[i])
3049                                 return -EINVAL;
3050                         if (max && value > max[i])
3051                                 return -EINVAL;
3052                 }
3053         }
3054         return 0;
3055 }
3056
3057 /* Strategy function to convert jiffies to seconds */
3058 int sysctl_jiffies(struct ctl_table *table,
3059                 void __user *oldval, size_t __user *oldlenp,
3060                 void __user *newval, size_t newlen)
3061 {
3062         if (oldval && oldlenp) {
3063                 size_t olen;
3064
3065                 if (get_user(olen, oldlenp))
3066                         return -EFAULT;
3067                 if (olen) {
3068                         int val;
3069
3070                         if (olen < sizeof(int))
3071                                 return -EINVAL;
3072
3073                         val = *(int *)(table->data) / HZ;
3074                         if (put_user(val, (int __user *)oldval))
3075                                 return -EFAULT;
3076                         if (put_user(sizeof(int), oldlenp))
3077                                 return -EFAULT;
3078                 }
3079         }
3080         if (newval && newlen) {
3081                 int new;
3082                 if (newlen != sizeof(int))
3083                         return -EINVAL;
3084                 if (get_user(new, (int __user *)newval))
3085                         return -EFAULT;
3086                 *(int *)(table->data) = new*HZ;
3087         }
3088         return 1;
3089 }
3090
3091 /* Strategy function to convert jiffies to seconds */
3092 int sysctl_ms_jiffies(struct ctl_table *table,
3093                 void __user *oldval, size_t __user *oldlenp,
3094                 void __user *newval, size_t newlen)
3095 {
3096         if (oldval && oldlenp) {
3097                 size_t olen;
3098
3099                 if (get_user(olen, oldlenp))
3100                         return -EFAULT;
3101                 if (olen) {
3102                         int val;
3103
3104                         if (olen < sizeof(int))
3105                                 return -EINVAL;
3106
3107                         val = jiffies_to_msecs(*(int *)(table->data));
3108                         if (put_user(val, (int __user *)oldval))
3109                                 return -EFAULT;
3110                         if (put_user(sizeof(int), oldlenp))
3111                                 return -EFAULT;
3112                 }
3113         }
3114         if (newval && newlen) {
3115                 int new;
3116                 if (newlen != sizeof(int))
3117                         return -EINVAL;
3118                 if (get_user(new, (int __user *)newval))
3119                         return -EFAULT;
3120                 *(int *)(table->data) = msecs_to_jiffies(new);
3121         }
3122         return 1;
3123 }
3124
3125
3126
3127 #else /* CONFIG_SYSCTL_SYSCALL */
3128
3129
3130 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3131 {
3132         struct __sysctl_args tmp;
3133         int error;
3134
3135         if (copy_from_user(&tmp, args, sizeof(tmp)))
3136                 return -EFAULT;
3137
3138         error = deprecated_sysctl_warning(&tmp);
3139
3140         /* If no error reading the parameters then just -ENOSYS ... */
3141         if (!error)
3142                 error = -ENOSYS;
3143
3144         return error;
3145 }
3146
3147 int sysctl_data(struct ctl_table *table,
3148                   void __user *oldval, size_t __user *oldlenp,
3149                   void __user *newval, size_t newlen)
3150 {
3151         return -ENOSYS;
3152 }
3153
3154 int sysctl_string(struct ctl_table *table,
3155                   void __user *oldval, size_t __user *oldlenp,
3156                   void __user *newval, size_t newlen)
3157 {
3158         return -ENOSYS;
3159 }
3160
3161 int sysctl_intvec(struct ctl_table *table,
3162                 void __user *oldval, size_t __user *oldlenp,
3163                 void __user *newval, size_t newlen)
3164 {
3165         return -ENOSYS;
3166 }
3167
3168 int sysctl_jiffies(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_ms_jiffies(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 #endif /* CONFIG_SYSCTL_SYSCALL */
3183
3184 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3185 {
3186         static int msg_count;
3187         int name[CTL_MAXNAME];
3188         int i;
3189
3190         /* Check args->nlen. */
3191         if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3192                 return -ENOTDIR;
3193
3194         /* Read in the sysctl name for better debug message logging */
3195         for (i = 0; i < args->nlen; i++)
3196                 if (get_user(name[i], args->name + i))
3197                         return -EFAULT;
3198
3199         /* Ignore accesses to kernel.version */
3200         if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3201                 return 0;
3202
3203         if (msg_count < 5) {
3204                 msg_count++;
3205                 printk(KERN_INFO
3206                         "warning: process `%s' used the deprecated sysctl "
3207                         "system call with ", current->comm);
3208                 for (i = 0; i < args->nlen; i++)
3209                         printk("%d.", name[i]);
3210                 printk("\n");
3211         }
3212         return 0;
3213 }
3214
3215 /*
3216  * No sense putting this after each symbol definition, twice,
3217  * exception granted :-)
3218  */
3219 EXPORT_SYMBOL(proc_dointvec);
3220 EXPORT_SYMBOL(proc_dointvec_jiffies);
3221 EXPORT_SYMBOL(proc_dointvec_minmax);
3222 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3223 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3224 EXPORT_SYMBOL(proc_dostring);
3225 EXPORT_SYMBOL(proc_doulongvec_minmax);
3226 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3227 EXPORT_SYMBOL(register_sysctl_table);
3228 EXPORT_SYMBOL(register_sysctl_paths);
3229 EXPORT_SYMBOL(sysctl_intvec);
3230 EXPORT_SYMBOL(sysctl_jiffies);
3231 EXPORT_SYMBOL(sysctl_ms_jiffies);
3232 EXPORT_SYMBOL(sysctl_string);
3233 EXPORT_SYMBOL(sysctl_data);
3234 EXPORT_SYMBOL(unregister_sysctl_table);