git.oblomov.eu Git - linux-2.6/blob - kernel/sysctl.c

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/mm.h>
  23 #include <linux/swap.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/security.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/smp_lock.h>
  31 #include <linux/fs.h>
  32 #include <linux/init.h>
  33 #include <linux/kernel.h>
  34 #include <linux/kobject.h>
  35 #include <linux/net.h>
  36 #include <linux/sysrq.h>
  37 #include <linux/highuid.h>
  38 #include <linux/writeback.h>
  39 #include <linux/hugetlb.h>
  40 #include <linux/initrd.h>
  41 #include <linux/key.h>
  42 #include <linux/times.h>
  43 #include <linux/limits.h>
  44 #include <linux/dcache.h>
  45 #include <linux/syscalls.h>
  46 #include <linux/vmstat.h>
  47 #include <linux/nfs_fs.h>
  48 #include <linux/acpi.h>
  49 #include <linux/reboot.h>
  50 #include <linux/ftrace.h>
  51
  52 #include <asm/uaccess.h>
  53 #include <asm/processor.h>
  54
  55 #ifdef CONFIG_X86
  56 #include <asm/nmi.h>
  57 #include <asm/stacktrace.h>
  58 #include <asm/io.h>
  59 #endif
  60
  61 static int deprecated_sysctl_warning(struct __sysctl_args *args);
  62
  63 #if defined(CONFIG_SYSCTL)
  64
  65 /* External variables not in a header file. */
  66 extern int C_A_D;
  67 extern int print_fatal_signals;
  68 extern int sysctl_overcommit_memory;
  69 extern int sysctl_overcommit_ratio;
  70 extern int sysctl_panic_on_oom;
  71 extern int sysctl_oom_kill_allocating_task;
  72 extern int sysctl_oom_dump_tasks;
  73 extern int max_threads;
  74 extern int core_uses_pid;
  75 extern int suid_dumpable;
  76 extern char core_pattern[];
  77 extern int pid_max;
  78 extern int min_free_kbytes;
  79 extern int pid_max_min, pid_max_max;
  80 extern int sysctl_drop_caches;
  81 extern int percpu_pagelist_fraction;
  82 extern int compat_log;
  83 extern int latencytop_enabled;
  84 extern int sysctl_nr_open_min, sysctl_nr_open_max;
  85 #ifdef CONFIG_RCU_TORTURE_TEST
  86 extern int rcutorture_runnable;
  87 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
  88
  89 /* Constants used for minimum and  maximum */
  90 #ifdef CONFIG_DETECT_SOFTLOCKUP
  91 static int sixty = 60;
  92 static int neg_one = -1;
  93 #endif
  94
  95 #if defined(CONFIG_MMU) && defined(CONFIG_FILE_LOCKING)
  96 static int two = 2;
  97 #endif
  98
  99 static int zero;
 100 static int one = 1;
 101 static int one_hundred = 100;
 102
 103 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 104 static int maxolduid = 65535;
 105 static int minolduid;
 106 static int min_percpu_pagelist_fract = 8;
 107
 108 static int ngroups_max = NGROUPS_MAX;
 109
 110 #ifdef CONFIG_MODULES
 111 extern char modprobe_path[];
 112 #endif
 113 #ifdef CONFIG_CHR_DEV_SG
 114 extern int sg_big_buff;
 115 #endif
 116
 117 #ifdef CONFIG_SPARC
 118 #include <asm/system.h>
 119 #endif
 120
 121 #ifdef CONFIG_SPARC64
 122 extern int sysctl_tsb_ratio;
 123 #endif
 124
 125 #ifdef __hppa__
 126 extern int pwrsw_enabled;
 127 extern int unaligned_enabled;
 128 #endif
 129
 130 #ifdef CONFIG_S390
 131 #ifdef CONFIG_MATHEMU
 132 extern int sysctl_ieee_emulation_warnings;
 133 #endif
 134 extern int sysctl_userprocess_debug;
 135 extern int spin_retry;
 136 #endif
 137
 138 #ifdef CONFIG_BSD_PROCESS_ACCT
 139 extern int acct_parm[];
 140 #endif
 141
 142 #ifdef CONFIG_IA64
 143 extern int no_unaligned_warning;
 144 #endif
 145
 146 #ifdef CONFIG_RT_MUTEXES
 147 extern int max_lock_depth;
 148 #endif
 149
 150 #ifdef CONFIG_PROC_SYSCTL
 151 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
 152                   void __user *buffer, size_t *lenp, loff_t *ppos);
 153 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
 154                                void __user *buffer, size_t *lenp, loff_t *ppos);
 155 #endif
 156
 157 static struct ctl_table root_table[];
 158 static struct ctl_table_root sysctl_table_root;
 159 static struct ctl_table_header root_table_header = {
 160         .count = 1,
 161         .ctl_table = root_table,
 162         .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
 163         .root = &sysctl_table_root,
 164         .set = &sysctl_table_root.default_set,
 165 };
 166 static struct ctl_table_root sysctl_table_root = {
 167         .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
 168         .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
 169 };
 170
 171 static struct ctl_table kern_table[];
 172 static struct ctl_table vm_table[];
 173 static struct ctl_table fs_table[];
 174 static struct ctl_table debug_table[];
 175 static struct ctl_table dev_table[];
 176 extern struct ctl_table random_table[];
 177 #ifdef CONFIG_INOTIFY_USER
 178 extern struct ctl_table inotify_table[];
 179 #endif
 180 #ifdef CONFIG_EPOLL
 181 extern struct ctl_table epoll_table[];
 182 #endif
 183
 184 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 185 int sysctl_legacy_va_layout;
 186 #endif
 187
 188 extern int prove_locking;
 189 extern int lock_stat;
 190
 191 /* The default sysctl tables: */
 192
 193 static struct ctl_table root_table[] = {
 194         {
 195                 .ctl_name       = CTL_KERN,
 196                 .procname       = "kernel",
 197                 .mode           = 0555,
 198                 .child          = kern_table,
 199         },
 200         {
 201                 .ctl_name       = CTL_VM,
 202                 .procname       = "vm",
 203                 .mode           = 0555,
 204                 .child          = vm_table,
 205         },
 206         {
 207                 .ctl_name       = CTL_FS,
 208                 .procname       = "fs",
 209                 .mode           = 0555,
 210                 .child          = fs_table,
 211         },
 212         {
 213                 .ctl_name       = CTL_DEBUG,
 214                 .procname       = "debug",
 215                 .mode           = 0555,
 216                 .child          = debug_table,
 217         },
 218         {
 219                 .ctl_name       = CTL_DEV,
 220                 .procname       = "dev",
 221                 .mode           = 0555,
 222                 .child          = dev_table,
 223         },
 224 /*
 225  * NOTE: do not add new entries to this table unless you have read
 226  * Documentation/sysctl/ctl_unnumbered.txt
 227  */
 228         { .ctl_name = 0 }
 229 };
 230
 231 #ifdef CONFIG_SCHED_DEBUG
 232 static int min_sched_granularity_ns = 100000;           /* 100 usecs */
 233 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
 234 static int min_wakeup_granularity_ns;                   /* 0 usecs */
 235 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
 236 #endif
 237
 238 static struct ctl_table kern_table[] = {
 239 #ifdef CONFIG_SCHED_DEBUG
 240         {
 241                 .ctl_name       = CTL_UNNUMBERED,
 242                 .procname       = "sched_min_granularity_ns",
 243                 .data           = &sysctl_sched_min_granularity,
 244                 .maxlen         = sizeof(unsigned int),
 245                 .mode           = 0644,
 246                 .proc_handler   = &sched_nr_latency_handler,
 247                 .strategy       = &sysctl_intvec,
 248                 .extra1         = &min_sched_granularity_ns,
 249                 .extra2         = &max_sched_granularity_ns,
 250         },
 251         {
 252                 .ctl_name       = CTL_UNNUMBERED,
 253                 .procname       = "sched_latency_ns",
 254                 .data           = &sysctl_sched_latency,
 255                 .maxlen         = sizeof(unsigned int),
 256                 .mode           = 0644,
 257                 .proc_handler   = &sched_nr_latency_handler,
 258                 .strategy       = &sysctl_intvec,
 259                 .extra1         = &min_sched_granularity_ns,
 260                 .extra2         = &max_sched_granularity_ns,
 261         },
 262         {
 263                 .ctl_name       = CTL_UNNUMBERED,
 264                 .procname       = "sched_wakeup_granularity_ns",
 265                 .data           = &sysctl_sched_wakeup_granularity,
 266                 .maxlen         = sizeof(unsigned int),
 267                 .mode           = 0644,
 268                 .proc_handler   = &proc_dointvec_minmax,
 269                 .strategy       = &sysctl_intvec,
 270                 .extra1         = &min_wakeup_granularity_ns,
 271                 .extra2         = &max_wakeup_granularity_ns,
 272         },
 273         {
 274                 .ctl_name       = CTL_UNNUMBERED,
 275                 .procname       = "sched_shares_ratelimit",
 276                 .data           = &sysctl_sched_shares_ratelimit,
 277                 .maxlen         = sizeof(unsigned int),
 278                 .mode           = 0644,
 279                 .proc_handler   = &proc_dointvec,
 280         },
 281         {
 282                 .ctl_name       = CTL_UNNUMBERED,
 283                 .procname       = "sched_shares_thresh",
 284                 .data           = &sysctl_sched_shares_thresh,
 285                 .maxlen         = sizeof(unsigned int),
 286                 .mode           = 0644,
 287                 .proc_handler   = &proc_dointvec_minmax,
 288                 .strategy       = &sysctl_intvec,
 289                 .extra1         = &zero,
 290         },
 291         {
 292                 .ctl_name       = CTL_UNNUMBERED,
 293                 .procname       = "sched_child_runs_first",
 294                 .data           = &sysctl_sched_child_runs_first,
 295                 .maxlen         = sizeof(unsigned int),
 296                 .mode           = 0644,
 297                 .proc_handler   = &proc_dointvec,
 298         },
 299         {
 300                 .ctl_name       = CTL_UNNUMBERED,
 301                 .procname       = "sched_features",
 302                 .data           = &sysctl_sched_features,
 303                 .maxlen         = sizeof(unsigned int),
 304                 .mode           = 0644,
 305                 .proc_handler   = &proc_dointvec,
 306         },
 307         {
 308                 .ctl_name       = CTL_UNNUMBERED,
 309                 .procname       = "sched_migration_cost",
 310                 .data           = &sysctl_sched_migration_cost,
 311                 .maxlen         = sizeof(unsigned int),
 312                 .mode           = 0644,
 313                 .proc_handler   = &proc_dointvec,
 314         },
 315         {
 316                 .ctl_name       = CTL_UNNUMBERED,
 317                 .procname       = "sched_nr_migrate",
 318                 .data           = &sysctl_sched_nr_migrate,
 319                 .maxlen         = sizeof(unsigned int),
 320                 .mode           = 0644,
 321                 .proc_handler   = &proc_dointvec,
 322         },
 323 #endif
 324         {
 325                 .ctl_name       = CTL_UNNUMBERED,
 326                 .procname       = "sched_rt_period_us",
 327                 .data           = &sysctl_sched_rt_period,
 328                 .maxlen         = sizeof(unsigned int),
 329                 .mode           = 0644,
 330                 .proc_handler   = &sched_rt_handler,
 331         },
 332         {
 333                 .ctl_name       = CTL_UNNUMBERED,
 334                 .procname       = "sched_rt_runtime_us",
 335                 .data           = &sysctl_sched_rt_runtime,
 336                 .maxlen         = sizeof(int),
 337                 .mode           = 0644,
 338                 .proc_handler   = &sched_rt_handler,
 339         },
 340         {
 341                 .ctl_name       = CTL_UNNUMBERED,
 342                 .procname       = "sched_compat_yield",
 343                 .data           = &sysctl_sched_compat_yield,
 344                 .maxlen         = sizeof(unsigned int),
 345                 .mode           = 0644,
 346                 .proc_handler   = &proc_dointvec,
 347         },
 348 #ifdef CONFIG_PROVE_LOCKING
 349         {
 350                 .ctl_name       = CTL_UNNUMBERED,
 351                 .procname       = "prove_locking",
 352                 .data           = &prove_locking,
 353                 .maxlen         = sizeof(int),
 354                 .mode           = 0644,
 355                 .proc_handler   = &proc_dointvec,
 356         },
 357 #endif
 358 #ifdef CONFIG_LOCK_STAT
 359         {
 360                 .ctl_name       = CTL_UNNUMBERED,
 361                 .procname       = "lock_stat",
 362                 .data           = &lock_stat,
 363                 .maxlen         = sizeof(int),
 364                 .mode           = 0644,
 365                 .proc_handler   = &proc_dointvec,
 366         },
 367 #endif
 368         {
 369                 .ctl_name       = KERN_PANIC,
 370                 .procname       = "panic",
 371                 .data           = &panic_timeout,
 372                 .maxlen         = sizeof(int),
 373                 .mode           = 0644,
 374                 .proc_handler   = &proc_dointvec,
 375         },
 376         {
 377                 .ctl_name       = KERN_CORE_USES_PID,
 378                 .procname       = "core_uses_pid",
 379                 .data           = &core_uses_pid,
 380                 .maxlen         = sizeof(int),
 381                 .mode           = 0644,
 382                 .proc_handler   = &proc_dointvec,
 383         },
 384         {
 385                 .ctl_name       = KERN_CORE_PATTERN,
 386                 .procname       = "core_pattern",
 387                 .data           = core_pattern,
 388                 .maxlen         = CORENAME_MAX_SIZE,
 389                 .mode           = 0644,
 390                 .proc_handler   = &proc_dostring,
 391                 .strategy       = &sysctl_string,
 392         },
 393 #ifdef CONFIG_PROC_SYSCTL
 394         {
 395                 .procname       = "tainted",
 396                 .maxlen         = sizeof(long),
 397                 .mode           = 0644,
 398                 .proc_handler   = &proc_taint,
 399         },
 400 #endif
 401 #ifdef CONFIG_LATENCYTOP
 402         {
 403                 .procname       = "latencytop",
 404                 .data           = &latencytop_enabled,
 405                 .maxlen         = sizeof(int),
 406                 .mode           = 0644,
 407                 .proc_handler   = &proc_dointvec,
 408         },
 409 #endif
 410 #ifdef CONFIG_BLK_DEV_INITRD
 411         {
 412                 .ctl_name       = KERN_REALROOTDEV,
 413                 .procname       = "real-root-dev",
 414                 .data           = &real_root_dev,
 415                 .maxlen         = sizeof(int),
 416                 .mode           = 0644,
 417                 .proc_handler   = &proc_dointvec,
 418         },
 419 #endif
 420         {
 421                 .ctl_name       = CTL_UNNUMBERED,
 422                 .procname       = "print-fatal-signals",
 423                 .data           = &print_fatal_signals,
 424                 .maxlen         = sizeof(int),
 425                 .mode           = 0644,
 426                 .proc_handler   = &proc_dointvec,
 427         },
 428 #ifdef CONFIG_SPARC
 429         {
 430                 .ctl_name       = KERN_SPARC_REBOOT,
 431                 .procname       = "reboot-cmd",
 432                 .data           = reboot_command,
 433                 .maxlen         = 256,
 434                 .mode           = 0644,
 435                 .proc_handler   = &proc_dostring,
 436                 .strategy       = &sysctl_string,
 437         },
 438         {
 439                 .ctl_name       = KERN_SPARC_STOP_A,
 440                 .procname       = "stop-a",
 441                 .data           = &stop_a_enabled,
 442                 .maxlen         = sizeof (int),
 443                 .mode           = 0644,
 444                 .proc_handler   = &proc_dointvec,
 445         },
 446         {
 447                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 448                 .procname       = "scons-poweroff",
 449                 .data           = &scons_pwroff,
 450                 .maxlen         = sizeof (int),
 451                 .mode           = 0644,
 452                 .proc_handler   = &proc_dointvec,
 453         },
 454 #endif
 455 #ifdef CONFIG_SPARC64
 456         {
 457                 .ctl_name       = CTL_UNNUMBERED,
 458                 .procname       = "tsb-ratio",
 459                 .data           = &sysctl_tsb_ratio,
 460                 .maxlen         = sizeof (int),
 461                 .mode           = 0644,
 462                 .proc_handler   = &proc_dointvec,
 463         },
 464 #endif
 465 #ifdef __hppa__
 466         {
 467                 .ctl_name       = KERN_HPPA_PWRSW,
 468                 .procname       = "soft-power",
 469                 .data           = &pwrsw_enabled,
 470                 .maxlen         = sizeof (int),
 471                 .mode           = 0644,
 472                 .proc_handler   = &proc_dointvec,
 473         },
 474         {
 475                 .ctl_name       = KERN_HPPA_UNALIGNED,
 476                 .procname       = "unaligned-trap",
 477                 .data           = &unaligned_enabled,
 478                 .maxlen         = sizeof (int),
 479                 .mode           = 0644,
 480                 .proc_handler   = &proc_dointvec,
 481         },
 482 #endif
 483         {
 484                 .ctl_name       = KERN_CTLALTDEL,
 485                 .procname       = "ctrl-alt-del",
 486                 .data           = &C_A_D,
 487                 .maxlen         = sizeof(int),
 488                 .mode           = 0644,
 489                 .proc_handler   = &proc_dointvec,
 490         },
 491 #ifdef CONFIG_FUNCTION_TRACER
 492         {
 493                 .ctl_name       = CTL_UNNUMBERED,
 494                 .procname       = "ftrace_enabled",
 495                 .data           = &ftrace_enabled,
 496                 .maxlen         = sizeof(int),
 497                 .mode           = 0644,
 498                 .proc_handler   = &ftrace_enable_sysctl,
 499         },
 500 #endif
 501 #ifdef CONFIG_STACK_TRACER
 502         {
 503                 .ctl_name       = CTL_UNNUMBERED,
 504                 .procname       = "stack_tracer_enabled",
 505                 .data           = &stack_tracer_enabled,
 506                 .maxlen         = sizeof(int),
 507                 .mode           = 0644,
 508                 .proc_handler   = &stack_trace_sysctl,
 509         },
 510 #endif
 511 #ifdef CONFIG_TRACING
 512         {
 513                 .ctl_name       = CTL_UNNUMBERED,
 514                 .procname       = "ftrace_dump_on_oops",
 515                 .data           = &ftrace_dump_on_oops,
 516                 .maxlen         = sizeof(int),
 517                 .mode           = 0644,
 518                 .proc_handler   = &proc_dointvec,
 519         },
 520 #endif
 521 #ifdef CONFIG_MODULES
 522         {
 523                 .ctl_name       = KERN_MODPROBE,
 524                 .procname       = "modprobe",
 525                 .data           = &modprobe_path,
 526                 .maxlen         = KMOD_PATH_LEN,
 527                 .mode           = 0644,
 528                 .proc_handler   = &proc_dostring,
 529                 .strategy       = &sysctl_string,
 530         },
 531 #endif
 532 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 533         {
 534                 .ctl_name       = KERN_HOTPLUG,
 535                 .procname       = "hotplug",
 536                 .data           = &uevent_helper,
 537                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 538                 .mode           = 0644,
 539                 .proc_handler   = &proc_dostring,
 540                 .strategy       = &sysctl_string,
 541         },
 542 #endif
 543 #ifdef CONFIG_CHR_DEV_SG
 544         {
 545                 .ctl_name       = KERN_SG_BIG_BUFF,
 546                 .procname       = "sg-big-buff",
 547                 .data           = &sg_big_buff,
 548                 .maxlen         = sizeof (int),
 549                 .mode           = 0444,
 550                 .proc_handler   = &proc_dointvec,
 551         },
 552 #endif
 553 #ifdef CONFIG_BSD_PROCESS_ACCT
 554         {
 555                 .ctl_name       = KERN_ACCT,
 556                 .procname       = "acct",
 557                 .data           = &acct_parm,
 558                 .maxlen         = 3*sizeof(int),
 559                 .mode           = 0644,
 560                 .proc_handler   = &proc_dointvec,
 561         },
 562 #endif
 563 #ifdef CONFIG_MAGIC_SYSRQ
 564         {
 565                 .ctl_name       = KERN_SYSRQ,
 566                 .procname       = "sysrq",
 567                 .data           = &__sysrq_enabled,
 568                 .maxlen         = sizeof (int),
 569                 .mode           = 0644,
 570                 .proc_handler   = &proc_dointvec,
 571         },
 572 #endif
 573 #ifdef CONFIG_PROC_SYSCTL
 574         {
 575                 .procname       = "cad_pid",
 576                 .data           = NULL,
 577                 .maxlen         = sizeof (int),
 578                 .mode           = 0600,
 579                 .proc_handler   = &proc_do_cad_pid,
 580         },
 581 #endif
 582         {
 583                 .ctl_name       = KERN_MAX_THREADS,
 584                 .procname       = "threads-max",
 585                 .data           = &max_threads,
 586                 .maxlen         = sizeof(int),
 587                 .mode           = 0644,
 588                 .proc_handler   = &proc_dointvec,
 589         },
 590         {
 591                 .ctl_name       = KERN_RANDOM,
 592                 .procname       = "random",
 593                 .mode           = 0555,
 594                 .child          = random_table,
 595         },
 596         {
 597                 .ctl_name       = KERN_OVERFLOWUID,
 598                 .procname       = "overflowuid",
 599                 .data           = &overflowuid,
 600                 .maxlen         = sizeof(int),
 601                 .mode           = 0644,
 602                 .proc_handler   = &proc_dointvec_minmax,
 603                 .strategy       = &sysctl_intvec,
 604                 .extra1         = &minolduid,
 605                 .extra2         = &maxolduid,
 606         },
 607         {
 608                 .ctl_name       = KERN_OVERFLOWGID,
 609                 .procname       = "overflowgid",
 610                 .data           = &overflowgid,
 611                 .maxlen         = sizeof(int),
 612                 .mode           = 0644,
 613                 .proc_handler   = &proc_dointvec_minmax,
 614                 .strategy       = &sysctl_intvec,
 615                 .extra1         = &minolduid,
 616                 .extra2         = &maxolduid,
 617         },
 618 #ifdef CONFIG_S390
 619 #ifdef CONFIG_MATHEMU
 620         {
 621                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 622                 .procname       = "ieee_emulation_warnings",
 623                 .data           = &sysctl_ieee_emulation_warnings,
 624                 .maxlen         = sizeof(int),
 625                 .mode           = 0644,
 626                 .proc_handler   = &proc_dointvec,
 627         },
 628 #endif
 629         {
 630                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 631                 .procname       = "userprocess_debug",
 632                 .data           = &sysctl_userprocess_debug,
 633                 .maxlen         = sizeof(int),
 634                 .mode           = 0644,
 635                 .proc_handler   = &proc_dointvec,
 636         },
 637 #endif
 638         {
 639                 .ctl_name       = KERN_PIDMAX,
 640                 .procname       = "pid_max",
 641                 .data           = &pid_max,
 642                 .maxlen         = sizeof (int),
 643                 .mode           = 0644,
 644                 .proc_handler   = &proc_dointvec_minmax,
 645                 .strategy       = sysctl_intvec,
 646                 .extra1         = &pid_max_min,
 647                 .extra2         = &pid_max_max,
 648         },
 649         {
 650                 .ctl_name       = KERN_PANIC_ON_OOPS,
 651                 .procname       = "panic_on_oops",
 652                 .data           = &panic_on_oops,
 653                 .maxlen         = sizeof(int),
 654                 .mode           = 0644,
 655                 .proc_handler   = &proc_dointvec,
 656         },
 657 #if defined CONFIG_PRINTK
 658         {
 659                 .ctl_name       = KERN_PRINTK,
 660                 .procname       = "printk",
 661                 .data           = &console_loglevel,
 662                 .maxlen         = 4*sizeof(int),
 663                 .mode           = 0644,
 664                 .proc_handler   = &proc_dointvec,
 665         },
 666         {
 667                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 668                 .procname       = "printk_ratelimit",
 669                 .data           = &printk_ratelimit_state.interval,
 670                 .maxlen         = sizeof(int),
 671                 .mode           = 0644,
 672                 .proc_handler   = &proc_dointvec_jiffies,
 673                 .strategy       = &sysctl_jiffies,
 674         },
 675         {
 676                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 677                 .procname       = "printk_ratelimit_burst",
 678                 .data           = &printk_ratelimit_state.burst,
 679                 .maxlen         = sizeof(int),
 680                 .mode           = 0644,
 681                 .proc_handler   = &proc_dointvec,
 682         },
 683 #endif
 684         {
 685                 .ctl_name       = KERN_NGROUPS_MAX,
 686                 .procname       = "ngroups_max",
 687                 .data           = &ngroups_max,
 688                 .maxlen         = sizeof (int),
 689                 .mode           = 0444,
 690                 .proc_handler   = &proc_dointvec,
 691         },
 692 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 693         {
 694                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 695                 .procname       = "unknown_nmi_panic",
 696                 .data           = &unknown_nmi_panic,
 697                 .maxlen         = sizeof (int),
 698                 .mode           = 0644,
 699                 .proc_handler   = &proc_dointvec,
 700         },
 701         {
 702                 .procname       = "nmi_watchdog",
 703                 .data           = &nmi_watchdog_enabled,
 704                 .maxlen         = sizeof (int),
 705                 .mode           = 0644,
 706                 .proc_handler   = &proc_nmi_enabled,
 707         },
 708 #endif
 709 #if defined(CONFIG_X86)
 710         {
 711                 .ctl_name       = KERN_PANIC_ON_NMI,
 712                 .procname       = "panic_on_unrecovered_nmi",
 713                 .data           = &panic_on_unrecovered_nmi,
 714                 .maxlen         = sizeof(int),
 715                 .mode           = 0644,
 716                 .proc_handler   = &proc_dointvec,
 717         },
 718         {
 719                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 720                 .procname       = "bootloader_type",
 721                 .data           = &bootloader_type,
 722                 .maxlen         = sizeof (int),
 723                 .mode           = 0444,
 724                 .proc_handler   = &proc_dointvec,
 725         },
 726         {
 727                 .ctl_name       = CTL_UNNUMBERED,
 728                 .procname       = "kstack_depth_to_print",
 729                 .data           = &kstack_depth_to_print,
 730                 .maxlen         = sizeof(int),
 731                 .mode           = 0644,
 732                 .proc_handler   = &proc_dointvec,
 733         },
 734         {
 735                 .ctl_name       = CTL_UNNUMBERED,
 736                 .procname       = "io_delay_type",
 737                 .data           = &io_delay_type,
 738                 .maxlen         = sizeof(int),
 739                 .mode           = 0644,
 740                 .proc_handler   = &proc_dointvec,
 741         },
 742 #endif
 743 #if defined(CONFIG_MMU)
 744         {
 745                 .ctl_name       = KERN_RANDOMIZE,
 746                 .procname       = "randomize_va_space",
 747                 .data           = &randomize_va_space,
 748                 .maxlen         = sizeof(int),
 749                 .mode           = 0644,
 750                 .proc_handler   = &proc_dointvec,
 751         },
 752 #endif
 753 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 754         {
 755                 .ctl_name       = KERN_SPIN_RETRY,
 756                 .procname       = "spin_retry",
 757                 .data           = &spin_retry,
 758                 .maxlen         = sizeof (int),
 759                 .mode           = 0644,
 760                 .proc_handler   = &proc_dointvec,
 761         },
 762 #endif
 763 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 764         {
 765                 .procname       = "acpi_video_flags",
 766                 .data           = &acpi_realmode_flags,
 767                 .maxlen         = sizeof (unsigned long),
 768                 .mode           = 0644,
 769                 .proc_handler   = &proc_doulongvec_minmax,
 770         },
 771 #endif
 772 #ifdef CONFIG_IA64
 773         {
 774                 .ctl_name       = KERN_IA64_UNALIGNED,
 775                 .procname       = "ignore-unaligned-usertrap",
 776                 .data           = &no_unaligned_warning,
 777                 .maxlen         = sizeof (int),
 778                 .mode           = 0644,
 779                 .proc_handler   = &proc_dointvec,
 780         },
 781 #endif
 782 #ifdef CONFIG_DETECT_SOFTLOCKUP
 783         {
 784                 .ctl_name       = CTL_UNNUMBERED,
 785                 .procname       = "softlockup_panic",
 786                 .data           = &softlockup_panic,
 787                 .maxlen         = sizeof(int),
 788                 .mode           = 0644,
 789                 .proc_handler   = &proc_dointvec_minmax,
 790                 .strategy       = &sysctl_intvec,
 791                 .extra1         = &zero,
 792                 .extra2         = &one,
 793         },
 794         {
 795                 .ctl_name       = CTL_UNNUMBERED,
 796                 .procname       = "softlockup_thresh",
 797                 .data           = &softlockup_thresh,
 798                 .maxlen         = sizeof(int),
 799                 .mode           = 0644,
 800                 .proc_handler   = &proc_dointvec_minmax,
 801                 .strategy       = &sysctl_intvec,
 802                 .extra1         = &neg_one,
 803                 .extra2         = &sixty,
 804         },
 805         {
 806                 .ctl_name       = CTL_UNNUMBERED,
 807                 .procname       = "hung_task_check_count",
 808                 .data           = &sysctl_hung_task_check_count,
 809                 .maxlen         = sizeof(unsigned long),
 810                 .mode           = 0644,
 811                 .proc_handler   = &proc_doulongvec_minmax,
 812                 .strategy       = &sysctl_intvec,
 813         },
 814         {
 815                 .ctl_name       = CTL_UNNUMBERED,
 816                 .procname       = "hung_task_timeout_secs",
 817                 .data           = &sysctl_hung_task_timeout_secs,
 818                 .maxlen         = sizeof(unsigned long),
 819                 .mode           = 0644,
 820                 .proc_handler   = &proc_doulongvec_minmax,
 821                 .strategy       = &sysctl_intvec,
 822         },
 823         {
 824                 .ctl_name       = CTL_UNNUMBERED,
 825                 .procname       = "hung_task_warnings",
 826                 .data           = &sysctl_hung_task_warnings,
 827                 .maxlen         = sizeof(unsigned long),
 828                 .mode           = 0644,
 829                 .proc_handler   = &proc_doulongvec_minmax,
 830                 .strategy       = &sysctl_intvec,
 831         },
 832 #endif
 833 #ifdef CONFIG_COMPAT
 834         {
 835                 .ctl_name       = KERN_COMPAT_LOG,
 836                 .procname       = "compat-log",
 837                 .data           = &compat_log,
 838                 .maxlen         = sizeof (int),
 839                 .mode           = 0644,
 840                 .proc_handler   = &proc_dointvec,
 841         },
 842 #endif
 843 #ifdef CONFIG_RT_MUTEXES
 844         {
 845                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 846                 .procname       = "max_lock_depth",
 847                 .data           = &max_lock_depth,
 848                 .maxlen         = sizeof(int),
 849                 .mode           = 0644,
 850                 .proc_handler   = &proc_dointvec,
 851         },
 852 #endif
 853         {
 854                 .ctl_name       = CTL_UNNUMBERED,
 855                 .procname       = "poweroff_cmd",
 856                 .data           = &poweroff_cmd,
 857                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 858                 .mode           = 0644,
 859                 .proc_handler   = &proc_dostring,
 860                 .strategy       = &sysctl_string,
 861         },
 862 #ifdef CONFIG_KEYS
 863         {
 864                 .ctl_name       = CTL_UNNUMBERED,
 865                 .procname       = "keys",
 866                 .mode           = 0555,
 867                 .child          = key_sysctls,
 868         },
 869 #endif
 870 #ifdef CONFIG_RCU_TORTURE_TEST
 871         {
 872                 .ctl_name       = CTL_UNNUMBERED,
 873                 .procname       = "rcutorture_runnable",
 874                 .data           = &rcutorture_runnable,
 875                 .maxlen         = sizeof(int),
 876                 .mode           = 0644,
 877                 .proc_handler   = &proc_dointvec,
 878         },
 879 #endif
 880 #ifdef CONFIG_UNEVICTABLE_LRU
 881         {
 882                 .ctl_name       = CTL_UNNUMBERED,
 883                 .procname       = "scan_unevictable_pages",
 884                 .data           = &scan_unevictable_pages,
 885                 .maxlen         = sizeof(scan_unevictable_pages),
 886                 .mode           = 0644,
 887                 .proc_handler   = &scan_unevictable_handler,
 888         },
 889 #endif
 890 /*
 891  * NOTE: do not add new entries to this table unless you have read
 892  * Documentation/sysctl/ctl_unnumbered.txt
 893  */
 894         { .ctl_name = 0 }
 895 };
 896
 897 static struct ctl_table vm_table[] = {
 898         {
 899                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 900                 .procname       = "overcommit_memory",
 901                 .data           = &sysctl_overcommit_memory,
 902                 .maxlen         = sizeof(sysctl_overcommit_memory),
 903                 .mode           = 0644,
 904                 .proc_handler   = &proc_dointvec,
 905         },
 906         {
 907                 .ctl_name       = VM_PANIC_ON_OOM,
 908                 .procname       = "panic_on_oom",
 909                 .data           = &sysctl_panic_on_oom,
 910                 .maxlen         = sizeof(sysctl_panic_on_oom),
 911                 .mode           = 0644,
 912                 .proc_handler   = &proc_dointvec,
 913         },
 914         {
 915                 .ctl_name       = CTL_UNNUMBERED,
 916                 .procname       = "oom_kill_allocating_task",
 917                 .data           = &sysctl_oom_kill_allocating_task,
 918                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
 919                 .mode           = 0644,
 920                 .proc_handler   = &proc_dointvec,
 921         },
 922         {
 923                 .ctl_name       = CTL_UNNUMBERED,
 924                 .procname       = "oom_dump_tasks",
 925                 .data           = &sysctl_oom_dump_tasks,
 926                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
 927                 .mode           = 0644,
 928                 .proc_handler   = &proc_dointvec,
 929         },
 930         {
 931                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 932                 .procname       = "overcommit_ratio",
 933                 .data           = &sysctl_overcommit_ratio,
 934                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 935                 .mode           = 0644,
 936                 .proc_handler   = &proc_dointvec,
 937         },
 938         {
 939                 .ctl_name       = VM_PAGE_CLUSTER,
 940                 .procname       = "page-cluster",
 941                 .data           = &page_cluster,
 942                 .maxlen         = sizeof(int),
 943                 .mode           = 0644,
 944                 .proc_handler   = &proc_dointvec,
 945         },
 946         {
 947                 .ctl_name       = VM_DIRTY_BACKGROUND,
 948                 .procname       = "dirty_background_ratio",
 949                 .data           = &dirty_background_ratio,
 950                 .maxlen         = sizeof(dirty_background_ratio),
 951                 .mode           = 0644,
 952                 .proc_handler   = &dirty_background_ratio_handler,
 953                 .strategy       = &sysctl_intvec,
 954                 .extra1         = &zero,
 955                 .extra2         = &one_hundred,
 956         },
 957         {
 958                 .ctl_name       = CTL_UNNUMBERED,
 959                 .procname       = "dirty_background_bytes",
 960                 .data           = &dirty_background_bytes,
 961                 .maxlen         = sizeof(dirty_background_bytes),
 962                 .mode           = 0644,
 963                 .proc_handler   = &dirty_background_bytes_handler,
 964                 .strategy       = &sysctl_intvec,
 965                 .extra1         = &one,
 966         },
 967         {
 968                 .ctl_name       = VM_DIRTY_RATIO,
 969                 .procname       = "dirty_ratio",
 970                 .data           = &vm_dirty_ratio,
 971                 .maxlen         = sizeof(vm_dirty_ratio),
 972                 .mode           = 0644,
 973                 .proc_handler   = &dirty_ratio_handler,
 974                 .strategy       = &sysctl_intvec,
 975                 .extra1         = &zero,
 976                 .extra2         = &one_hundred,
 977         },
 978         {
 979                 .ctl_name       = CTL_UNNUMBERED,
 980                 .procname       = "dirty_bytes",
 981                 .data           = &vm_dirty_bytes,
 982                 .maxlen         = sizeof(vm_dirty_bytes),
 983                 .mode           = 0644,
 984                 .proc_handler   = &dirty_bytes_handler,
 985                 .strategy       = &sysctl_intvec,
 986                 .extra1         = &one,
 987         },
 988         {
 989                 .procname       = "dirty_writeback_centisecs",
 990                 .data           = &dirty_writeback_interval,
 991                 .maxlen         = sizeof(dirty_writeback_interval),
 992                 .mode           = 0644,
 993                 .proc_handler   = &dirty_writeback_centisecs_handler,
 994         },
 995         {
 996                 .procname       = "dirty_expire_centisecs",
 997                 .data           = &dirty_expire_interval,
 998                 .maxlen         = sizeof(dirty_expire_interval),
 999                 .mode           = 0644,
1000                 .proc_handler   = &proc_dointvec_userhz_jiffies,
1001         },
1002         {
1003                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
1004                 .procname       = "nr_pdflush_threads",
1005                 .data           = &nr_pdflush_threads,
1006                 .maxlen         = sizeof nr_pdflush_threads,
1007                 .mode           = 0444 /* read-only*/,
1008                 .proc_handler   = &proc_dointvec,
1009         },
1010         {
1011                 .ctl_name       = VM_SWAPPINESS,
1012                 .procname       = "swappiness",
1013                 .data           = &vm_swappiness,
1014                 .maxlen         = sizeof(vm_swappiness),
1015                 .mode           = 0644,
1016                 .proc_handler   = &proc_dointvec_minmax,
1017                 .strategy       = &sysctl_intvec,
1018                 .extra1         = &zero,
1019                 .extra2         = &one_hundred,
1020         },
1021 #ifdef CONFIG_HUGETLB_PAGE
1022          {
1023                 .procname       = "nr_hugepages",
1024                 .data           = NULL,
1025                 .maxlen         = sizeof(unsigned long),
1026                 .mode           = 0644,
1027                 .proc_handler   = &hugetlb_sysctl_handler,
1028                 .extra1         = (void *)&hugetlb_zero,
1029                 .extra2         = (void *)&hugetlb_infinity,
1030          },
1031          {
1032                 .ctl_name       = VM_HUGETLB_GROUP,
1033                 .procname       = "hugetlb_shm_group",
1034                 .data           = &sysctl_hugetlb_shm_group,
1035                 .maxlen         = sizeof(gid_t),
1036                 .mode           = 0644,
1037                 .proc_handler   = &proc_dointvec,
1038          },
1039          {
1040                 .ctl_name       = CTL_UNNUMBERED,
1041                 .procname       = "hugepages_treat_as_movable",
1042                 .data           = &hugepages_treat_as_movable,
1043                 .maxlen         = sizeof(int),
1044                 .mode           = 0644,
1045                 .proc_handler   = &hugetlb_treat_movable_handler,
1046         },
1047         {
1048                 .ctl_name       = CTL_UNNUMBERED,
1049                 .procname       = "nr_overcommit_hugepages",
1050                 .data           = NULL,
1051                 .maxlen         = sizeof(unsigned long),
1052                 .mode           = 0644,
1053                 .proc_handler   = &hugetlb_overcommit_handler,
1054                 .extra1         = (void *)&hugetlb_zero,
1055                 .extra2         = (void *)&hugetlb_infinity,
1056         },
1057 #endif
1058         {
1059                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
1060                 .procname       = "lowmem_reserve_ratio",
1061                 .data           = &sysctl_lowmem_reserve_ratio,
1062                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1063                 .mode           = 0644,
1064                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
1065                 .strategy       = &sysctl_intvec,
1066         },
1067         {
1068                 .ctl_name       = VM_DROP_PAGECACHE,
1069                 .procname       = "drop_caches",
1070                 .data           = &sysctl_drop_caches,
1071                 .maxlen         = sizeof(int),
1072                 .mode           = 0644,
1073                 .proc_handler   = drop_caches_sysctl_handler,
1074                 .strategy       = &sysctl_intvec,
1075         },
1076         {
1077                 .ctl_name       = VM_MIN_FREE_KBYTES,
1078                 .procname       = "min_free_kbytes",
1079                 .data           = &min_free_kbytes,
1080                 .maxlen         = sizeof(min_free_kbytes),
1081                 .mode           = 0644,
1082                 .proc_handler   = &min_free_kbytes_sysctl_handler,
1083                 .strategy       = &sysctl_intvec,
1084                 .extra1         = &zero,
1085         },
1086         {
1087                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
1088                 .procname       = "percpu_pagelist_fraction",
1089                 .data           = &percpu_pagelist_fraction,
1090                 .maxlen         = sizeof(percpu_pagelist_fraction),
1091                 .mode           = 0644,
1092                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
1093                 .strategy       = &sysctl_intvec,
1094                 .extra1         = &min_percpu_pagelist_fract,
1095         },
1096 #ifdef CONFIG_MMU
1097         {
1098                 .ctl_name       = VM_MAX_MAP_COUNT,
1099                 .procname       = "max_map_count",
1100                 .data           = &sysctl_max_map_count,
1101                 .maxlen         = sizeof(sysctl_max_map_count),
1102                 .mode           = 0644,
1103                 .proc_handler   = &proc_dointvec
1104         },
1105 #endif
1106         {
1107                 .ctl_name       = VM_LAPTOP_MODE,
1108                 .procname       = "laptop_mode",
1109                 .data           = &laptop_mode,
1110                 .maxlen         = sizeof(laptop_mode),
1111                 .mode           = 0644,
1112                 .proc_handler   = &proc_dointvec_jiffies,
1113                 .strategy       = &sysctl_jiffies,
1114         },
1115         {
1116                 .ctl_name       = VM_BLOCK_DUMP,
1117                 .procname       = "block_dump",
1118                 .data           = &block_dump,
1119                 .maxlen         = sizeof(block_dump),
1120                 .mode           = 0644,
1121                 .proc_handler   = &proc_dointvec,
1122                 .strategy       = &sysctl_intvec,
1123                 .extra1         = &zero,
1124         },
1125         {
1126                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
1127                 .procname       = "vfs_cache_pressure",
1128                 .data           = &sysctl_vfs_cache_pressure,
1129                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1130                 .mode           = 0644,
1131                 .proc_handler   = &proc_dointvec,
1132                 .strategy       = &sysctl_intvec,
1133                 .extra1         = &zero,
1134         },
1135 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1136         {
1137                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
1138                 .procname       = "legacy_va_layout",
1139                 .data           = &sysctl_legacy_va_layout,
1140                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1141                 .mode           = 0644,
1142                 .proc_handler   = &proc_dointvec,
1143                 .strategy       = &sysctl_intvec,
1144                 .extra1         = &zero,
1145         },
1146 #endif
1147 #ifdef CONFIG_NUMA
1148         {
1149                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
1150                 .procname       = "zone_reclaim_mode",
1151                 .data           = &zone_reclaim_mode,
1152                 .maxlen         = sizeof(zone_reclaim_mode),
1153                 .mode           = 0644,
1154                 .proc_handler   = &proc_dointvec,
1155                 .strategy       = &sysctl_intvec,
1156                 .extra1         = &zero,
1157         },
1158         {
1159                 .ctl_name       = VM_MIN_UNMAPPED,
1160                 .procname       = "min_unmapped_ratio",
1161                 .data           = &sysctl_min_unmapped_ratio,
1162                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1163                 .mode           = 0644,
1164                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1165                 .strategy       = &sysctl_intvec,
1166                 .extra1         = &zero,
1167                 .extra2         = &one_hundred,
1168         },
1169         {
1170                 .ctl_name       = VM_MIN_SLAB,
1171                 .procname       = "min_slab_ratio",
1172                 .data           = &sysctl_min_slab_ratio,
1173                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1174                 .mode           = 0644,
1175                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1176                 .strategy       = &sysctl_intvec,
1177                 .extra1         = &zero,
1178                 .extra2         = &one_hundred,
1179         },
1180 #endif
1181 #ifdef CONFIG_SMP
1182         {
1183                 .ctl_name       = CTL_UNNUMBERED,
1184                 .procname       = "stat_interval",
1185                 .data           = &sysctl_stat_interval,
1186                 .maxlen         = sizeof(sysctl_stat_interval),
1187                 .mode           = 0644,
1188                 .proc_handler   = &proc_dointvec_jiffies,
1189                 .strategy       = &sysctl_jiffies,
1190         },
1191 #endif
1192 #ifdef CONFIG_SECURITY
1193         {
1194                 .ctl_name       = CTL_UNNUMBERED,
1195                 .procname       = "mmap_min_addr",
1196                 .data           = &mmap_min_addr,
1197                 .maxlen         = sizeof(unsigned long),
1198                 .mode           = 0644,
1199                 .proc_handler   = &proc_doulongvec_minmax,
1200         },
1201 #endif
1202 #ifdef CONFIG_NUMA
1203         {
1204                 .ctl_name       = CTL_UNNUMBERED,
1205                 .procname       = "numa_zonelist_order",
1206                 .data           = &numa_zonelist_order,
1207                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1208                 .mode           = 0644,
1209                 .proc_handler   = &numa_zonelist_order_handler,
1210                 .strategy       = &sysctl_string,
1211         },
1212 #endif
1213 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1214    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1215         {
1216                 .ctl_name       = VM_VDSO_ENABLED,
1217                 .procname       = "vdso_enabled",
1218                 .data           = &vdso_enabled,
1219                 .maxlen         = sizeof(vdso_enabled),
1220                 .mode           = 0644,
1221                 .proc_handler   = &proc_dointvec,
1222                 .strategy       = &sysctl_intvec,
1223                 .extra1         = &zero,
1224         },
1225 #endif
1226 #ifdef CONFIG_HIGHMEM
1227         {
1228                 .ctl_name       = CTL_UNNUMBERED,
1229                 .procname       = "highmem_is_dirtyable",
1230                 .data           = &vm_highmem_is_dirtyable,
1231                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1232                 .mode           = 0644,
1233                 .proc_handler   = &proc_dointvec_minmax,
1234                 .strategy       = &sysctl_intvec,
1235                 .extra1         = &zero,
1236                 .extra2         = &one,
1237         },
1238 #endif
1239 /*
1240  * NOTE: do not add new entries to this table unless you have read
1241  * Documentation/sysctl/ctl_unnumbered.txt
1242  */
1243         { .ctl_name = 0 }
1244 };
1245
1246 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1247 static struct ctl_table binfmt_misc_table[] = {
1248         { .ctl_name = 0 }
1249 };
1250 #endif
1251
1252 static struct ctl_table fs_table[] = {
1253         {
1254                 .ctl_name       = FS_NRINODE,
1255                 .procname       = "inode-nr",
1256                 .data           = &inodes_stat,
1257                 .maxlen         = 2*sizeof(int),
1258                 .mode           = 0444,
1259                 .proc_handler   = &proc_dointvec,
1260         },
1261         {
1262                 .ctl_name       = FS_STATINODE,
1263                 .procname       = "inode-state",
1264                 .data           = &inodes_stat,
1265                 .maxlen         = 7*sizeof(int),
1266                 .mode           = 0444,
1267                 .proc_handler   = &proc_dointvec,
1268         },
1269         {
1270                 .procname       = "file-nr",
1271                 .data           = &files_stat,
1272                 .maxlen         = 3*sizeof(int),
1273                 .mode           = 0444,
1274                 .proc_handler   = &proc_nr_files,
1275         },
1276         {
1277                 .ctl_name       = FS_MAXFILE,
1278                 .procname       = "file-max",
1279                 .data           = &files_stat.max_files,
1280                 .maxlen         = sizeof(int),
1281                 .mode           = 0644,
1282                 .proc_handler   = &proc_dointvec,
1283         },
1284         {
1285                 .ctl_name       = CTL_UNNUMBERED,
1286                 .procname       = "nr_open",
1287                 .data           = &sysctl_nr_open,
1288                 .maxlen         = sizeof(int),
1289                 .mode           = 0644,
1290                 .proc_handler   = &proc_dointvec_minmax,
1291                 .extra1         = &sysctl_nr_open_min,
1292                 .extra2         = &sysctl_nr_open_max,
1293         },
1294         {
1295                 .ctl_name       = FS_DENTRY,
1296                 .procname       = "dentry-state",
1297                 .data           = &dentry_stat,
1298                 .maxlen         = 6*sizeof(int),
1299                 .mode           = 0444,
1300                 .proc_handler   = &proc_dointvec,
1301         },
1302         {
1303                 .ctl_name       = FS_OVERFLOWUID,
1304                 .procname       = "overflowuid",
1305                 .data           = &fs_overflowuid,
1306                 .maxlen         = sizeof(int),
1307                 .mode           = 0644,
1308                 .proc_handler   = &proc_dointvec_minmax,
1309                 .strategy       = &sysctl_intvec,
1310                 .extra1         = &minolduid,
1311                 .extra2         = &maxolduid,
1312         },
1313         {
1314                 .ctl_name       = FS_OVERFLOWGID,
1315                 .procname       = "overflowgid",
1316                 .data           = &fs_overflowgid,
1317                 .maxlen         = sizeof(int),
1318                 .mode           = 0644,
1319                 .proc_handler   = &proc_dointvec_minmax,
1320                 .strategy       = &sysctl_intvec,
1321                 .extra1         = &minolduid,
1322                 .extra2         = &maxolduid,
1323         },
1324 #ifdef CONFIG_FILE_LOCKING
1325         {
1326                 .ctl_name       = FS_LEASES,
1327                 .procname       = "leases-enable",
1328                 .data           = &leases_enable,
1329                 .maxlen         = sizeof(int),
1330                 .mode           = 0644,
1331                 .proc_handler   = &proc_dointvec,
1332         },
1333 #endif
1334 #ifdef CONFIG_DNOTIFY
1335         {
1336                 .ctl_name       = FS_DIR_NOTIFY,
1337                 .procname       = "dir-notify-enable",
1338                 .data           = &dir_notify_enable,
1339                 .maxlen         = sizeof(int),
1340                 .mode           = 0644,
1341                 .proc_handler   = &proc_dointvec,
1342         },
1343 #endif
1344 #ifdef CONFIG_MMU
1345 #ifdef CONFIG_FILE_LOCKING
1346         {
1347                 .ctl_name       = FS_LEASE_TIME,
1348                 .procname       = "lease-break-time",
1349                 .data           = &lease_break_time,
1350                 .maxlen         = sizeof(int),
1351                 .mode           = 0644,
1352                 .proc_handler   = &proc_dointvec_minmax,
1353                 .strategy       = &sysctl_intvec,
1354                 .extra1         = &zero,
1355                 .extra2         = &two,
1356         },
1357 #endif
1358 #ifdef CONFIG_AIO
1359         {
1360                 .procname       = "aio-nr",
1361                 .data           = &aio_nr,
1362                 .maxlen         = sizeof(aio_nr),
1363                 .mode           = 0444,
1364                 .proc_handler   = &proc_doulongvec_minmax,
1365         },
1366         {
1367                 .procname       = "aio-max-nr",
1368                 .data           = &aio_max_nr,
1369                 .maxlen         = sizeof(aio_max_nr),
1370                 .mode           = 0644,
1371                 .proc_handler   = &proc_doulongvec_minmax,
1372         },
1373 #endif /* CONFIG_AIO */
1374 #ifdef CONFIG_INOTIFY_USER
1375         {
1376                 .ctl_name       = FS_INOTIFY,
1377                 .procname       = "inotify",
1378                 .mode           = 0555,
1379                 .child          = inotify_table,
1380         },
1381 #endif
1382 #ifdef CONFIG_EPOLL
1383         {
1384                 .procname       = "epoll",
1385                 .mode           = 0555,
1386                 .child          = epoll_table,
1387         },
1388 #endif
1389 #endif
1390         {
1391                 .ctl_name       = KERN_SETUID_DUMPABLE,
1392                 .procname       = "suid_dumpable",
1393                 .data           = &suid_dumpable,
1394                 .maxlen         = sizeof(int),
1395                 .mode           = 0644,
1396                 .proc_handler   = &proc_dointvec,
1397         },
1398 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1399         {
1400                 .ctl_name       = CTL_UNNUMBERED,
1401                 .procname       = "binfmt_misc",
1402                 .mode           = 0555,
1403                 .child          = binfmt_misc_table,
1404         },
1405 #endif
1406 /*
1407  * NOTE: do not add new entries to this table unless you have read
1408  * Documentation/sysctl/ctl_unnumbered.txt
1409  */
1410         { .ctl_name = 0 }
1411 };
1412
1413 static struct ctl_table debug_table[] = {
1414 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1415         {
1416                 .ctl_name       = CTL_UNNUMBERED,
1417                 .procname       = "exception-trace",
1418                 .data           = &show_unhandled_signals,
1419                 .maxlen         = sizeof(int),
1420                 .mode           = 0644,
1421                 .proc_handler   = proc_dointvec
1422         },
1423 #endif
1424         { .ctl_name = 0 }
1425 };
1426
1427 static struct ctl_table dev_table[] = {
1428         { .ctl_name = 0 }
1429 };
1430
1431 static DEFINE_SPINLOCK(sysctl_lock);
1432
1433 /* called under sysctl_lock */
1434 static int use_table(struct ctl_table_header *p)
1435 {
1436         if (unlikely(p->unregistering))
1437                 return 0;
1438         p->used++;
1439         return 1;
1440 }
1441
1442 /* called under sysctl_lock */
1443 static void unuse_table(struct ctl_table_header *p)
1444 {
1445         if (!--p->used)
1446                 if (unlikely(p->unregistering))
1447                         complete(p->unregistering);
1448 }
1449
1450 /* called under sysctl_lock, will reacquire if has to wait */
1451 static void start_unregistering(struct ctl_table_header *p)
1452 {
1453         /*
1454          * if p->used is 0, nobody will ever touch that entry again;
1455          * we'll eliminate all paths to it before dropping sysctl_lock
1456          */
1457         if (unlikely(p->used)) {
1458                 struct completion wait;
1459                 init_completion(&wait);
1460                 p->unregistering = &wait;
1461                 spin_unlock(&sysctl_lock);
1462                 wait_for_completion(&wait);
1463                 spin_lock(&sysctl_lock);
1464         } else {
1465                 /* anything non-NULL; we'll never dereference it */
1466                 p->unregistering = ERR_PTR(-EINVAL);
1467         }
1468         /*
1469          * do not remove from the list until nobody holds it; walking the
1470          * list in do_sysctl() relies on that.
1471          */
1472         list_del_init(&p->ctl_entry);
1473 }
1474
1475 void sysctl_head_get(struct ctl_table_header *head)
1476 {
1477         spin_lock(&sysctl_lock);
1478         head->count++;
1479         spin_unlock(&sysctl_lock);
1480 }
1481
1482 void sysctl_head_put(struct ctl_table_header *head)
1483 {
1484         spin_lock(&sysctl_lock);
1485         if (!--head->count)
1486                 kfree(head);
1487         spin_unlock(&sysctl_lock);
1488 }
1489
1490 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1491 {
1492         if (!head)
1493                 BUG();
1494         spin_lock(&sysctl_lock);
1495         if (!use_table(head))
1496                 head = ERR_PTR(-ENOENT);
1497         spin_unlock(&sysctl_lock);
1498         return head;
1499 }
1500
1501 void sysctl_head_finish(struct ctl_table_header *head)
1502 {
1503         if (!head)
1504                 return;
1505         spin_lock(&sysctl_lock);
1506         unuse_table(head);
1507         spin_unlock(&sysctl_lock);
1508 }
1509
1510 static struct ctl_table_set *
1511 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1512 {
1513         struct ctl_table_set *set = &root->default_set;
1514         if (root->lookup)
1515                 set = root->lookup(root, namespaces);
1516         return set;
1517 }
1518
1519 static struct list_head *
1520 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1521 {
1522         struct ctl_table_set *set = lookup_header_set(root, namespaces);
1523         return &set->list;
1524 }
1525
1526 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1527                                             struct ctl_table_header *prev)
1528 {
1529         struct ctl_table_root *root;
1530         struct list_head *header_list;
1531         struct ctl_table_header *head;
1532         struct list_head *tmp;
1533
1534         spin_lock(&sysctl_lock);
1535         if (prev) {
1536                 head = prev;
1537                 tmp = &prev->ctl_entry;
1538                 unuse_table(prev);
1539                 goto next;
1540         }
1541         tmp = &root_table_header.ctl_entry;
1542         for (;;) {
1543                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1544
1545                 if (!use_table(head))
1546                         goto next;
1547                 spin_unlock(&sysctl_lock);
1548                 return head;
1549         next:
1550                 root = head->root;
1551                 tmp = tmp->next;
1552                 header_list = lookup_header_list(root, namespaces);
1553                 if (tmp != header_list)
1554                         continue;
1555
1556                 do {
1557                         root = list_entry(root->root_list.next,
1558                                         struct ctl_table_root, root_list);
1559                         if (root == &sysctl_table_root)
1560                                 goto out;
1561                         header_list = lookup_header_list(root, namespaces);
1562                 } while (list_empty(header_list));
1563                 tmp = header_list->next;
1564         }
1565 out:
1566         spin_unlock(&sysctl_lock);
1567         return NULL;
1568 }
1569
1570 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1571 {
1572         return __sysctl_head_next(current->nsproxy, prev);
1573 }
1574
1575 void register_sysctl_root(struct ctl_table_root *root)
1576 {
1577         spin_lock(&sysctl_lock);
1578         list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1579         spin_unlock(&sysctl_lock);
1580 }
1581
1582 #ifdef CONFIG_SYSCTL_SYSCALL
1583 /* Perform the actual read/write of a sysctl table entry. */
1584 static int do_sysctl_strategy(struct ctl_table_root *root,
1585                         struct ctl_table *table,
1586                         void __user *oldval, size_t __user *oldlenp,
1587                         void __user *newval, size_t newlen)
1588 {
1589         int op = 0, rc;
1590
1591         if (oldval)
1592                 op |= MAY_READ;
1593         if (newval)
1594                 op |= MAY_WRITE;
1595         if (sysctl_perm(root, table, op))
1596                 return -EPERM;
1597
1598         if (table->strategy) {
1599                 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1600                 if (rc < 0)
1601                         return rc;
1602                 if (rc > 0)
1603                         return 0;
1604         }
1605
1606         /* If there is no strategy routine, or if the strategy returns
1607          * zero, proceed with automatic r/w */
1608         if (table->data && table->maxlen) {
1609                 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1610                 if (rc < 0)
1611                         return rc;
1612         }
1613         return 0;
1614 }
1615
1616 static int parse_table(int __user *name, int nlen,
1617                        void __user *oldval, size_t __user *oldlenp,
1618                        void __user *newval, size_t newlen,
1619                        struct ctl_table_root *root,
1620                        struct ctl_table *table)
1621 {
1622         int n;
1623 repeat:
1624         if (!nlen)
1625                 return -ENOTDIR;
1626         if (get_user(n, name))
1627                 return -EFAULT;
1628         for ( ; table->ctl_name || table->procname; table++) {
1629                 if (!table->ctl_name)
1630                         continue;
1631                 if (n == table->ctl_name) {
1632                         int error;
1633                         if (table->child) {
1634                                 if (sysctl_perm(root, table, MAY_EXEC))
1635                                         return -EPERM;
1636                                 name++;
1637                                 nlen--;
1638                                 table = table->child;
1639                                 goto repeat;
1640                         }
1641                         error = do_sysctl_strategy(root, table,
1642                                                    oldval, oldlenp,
1643                                                    newval, newlen);
1644                         return error;
1645                 }
1646         }
1647         return -ENOTDIR;
1648 }
1649
1650 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1651                void __user *newval, size_t newlen)
1652 {
1653         struct ctl_table_header *head;
1654         int error = -ENOTDIR;
1655
1656         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1657                 return -ENOTDIR;
1658         if (oldval) {
1659                 int old_len;
1660                 if (!oldlenp || get_user(old_len, oldlenp))
1661                         return -EFAULT;
1662         }
1663
1664         for (head = sysctl_head_next(NULL); head;
1665                         head = sysctl_head_next(head)) {
1666                 error = parse_table(name, nlen, oldval, oldlenp,
1667                                         newval, newlen,
1668                                         head->root, head->ctl_table);
1669                 if (error != -ENOTDIR) {
1670                         sysctl_head_finish(head);
1671                         break;
1672                 }
1673         }
1674         return error;
1675 }
1676
1677 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1678 {
1679         struct __sysctl_args tmp;
1680         int error;
1681
1682         if (copy_from_user(&tmp, args, sizeof(tmp)))
1683                 return -EFAULT;
1684
1685         error = deprecated_sysctl_warning(&tmp);
1686         if (error)
1687                 goto out;
1688
1689         lock_kernel();
1690         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1691                           tmp.newval, tmp.newlen);
1692         unlock_kernel();
1693 out:
1694         return error;
1695 }
1696 #endif /* CONFIG_SYSCTL_SYSCALL */
1697
1698 /*
1699  * sysctl_perm does NOT grant the superuser all rights automatically, because
1700  * some sysctl variables are readonly even to root.
1701  */
1702
1703 static int test_perm(int mode, int op)
1704 {
1705         if (!current_euid())
1706                 mode >>= 6;
1707         else if (in_egroup_p(0))
1708                 mode >>= 3;
1709         if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1710                 return 0;
1711         return -EACCES;
1712 }
1713
1714 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1715 {
1716         int error;
1717         int mode;
1718
1719         error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1720         if (error)
1721                 return error;
1722
1723         if (root->permissions)
1724                 mode = root->permissions(root, current->nsproxy, table);
1725         else
1726                 mode = table->mode;
1727
1728         return test_perm(mode, op);
1729 }
1730
1731 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1732 {
1733         for (; table->ctl_name || table->procname; table++) {
1734                 table->parent = parent;
1735                 if (table->child)
1736                         sysctl_set_parent(table, table->child);
1737         }
1738 }
1739
1740 static __init int sysctl_init(void)
1741 {
1742         sysctl_set_parent(NULL, root_table);
1743 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1744         {
1745                 int err;
1746                 err = sysctl_check_table(current->nsproxy, root_table);
1747         }
1748 #endif
1749         return 0;
1750 }
1751
1752 core_initcall(sysctl_init);
1753
1754 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1755                                       struct ctl_table *table)
1756 {
1757         struct ctl_table *p;
1758         const char *s = branch->procname;
1759
1760         /* branch should have named subdirectory as its first element */
1761         if (!s || !branch->child)
1762                 return NULL;
1763
1764         /* ... and nothing else */
1765         if (branch[1].procname || branch[1].ctl_name)
1766                 return NULL;
1767
1768         /* table should contain subdirectory with the same name */
1769         for (p = table; p->procname || p->ctl_name; p++) {
1770                 if (!p->child)
1771                         continue;
1772                 if (p->procname && strcmp(p->procname, s) == 0)
1773                         return p;
1774         }
1775         return NULL;
1776 }
1777
1778 /* see if attaching q to p would be an improvement */
1779 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1780 {
1781         struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1782         struct ctl_table *next;
1783         int is_better = 0;
1784         int not_in_parent = !p->attached_by;
1785
1786         while ((next = is_branch_in(by, to)) != NULL) {
1787                 if (by == q->attached_by)
1788                         is_better = 1;
1789                 if (to == p->attached_by)
1790                         not_in_parent = 1;
1791                 by = by->child;
1792                 to = next->child;
1793         }
1794
1795         if (is_better && not_in_parent) {
1796                 q->attached_by = by;
1797                 q->attached_to = to;
1798                 q->parent = p;
1799         }
1800 }
1801
1802 /**
1803  * __register_sysctl_paths - register a sysctl hierarchy
1804  * @root: List of sysctl headers to register on
1805  * @namespaces: Data to compute which lists of sysctl entries are visible
1806  * @path: The path to the directory the sysctl table is in.
1807  * @table: the top-level table structure
1808  *
1809  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1810  * array. A completely 0 filled entry terminates the table.
1811  *
1812  * The members of the &struct ctl_table structure are used as follows:
1813  *
1814  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1815  *            must be unique within that level of sysctl
1816  *
1817  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1818  *            enter a sysctl file
1819  *
1820  * data - a pointer to data for use by proc_handler
1821  *
1822  * maxlen - the maximum size in bytes of the data
1823  *
1824  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1825  *
1826  * child - a pointer to the child sysctl table if this entry is a directory, or
1827  *         %NULL.
1828  *
1829  * proc_handler - the text handler routine (described below)
1830  *
1831  * strategy - the strategy routine (described below)
1832  *
1833  * de - for internal use by the sysctl routines
1834  *
1835  * extra1, extra2 - extra pointers usable by the proc handler routines
1836  *
1837  * Leaf nodes in the sysctl tree will be represented by a single file
1838  * under /proc; non-leaf nodes will be represented by directories.
1839  *
1840  * sysctl(2) can automatically manage read and write requests through
1841  * the sysctl table.  The data and maxlen fields of the ctl_table
1842  * struct enable minimal validation of the values being written to be
1843  * performed, and the mode field allows minimal authentication.
1844  *
1845  * More sophisticated management can be enabled by the provision of a
1846  * strategy routine with the table entry.  This will be called before
1847  * any automatic read or write of the data is performed.
1848  *
1849  * The strategy routine may return
1850  *
1851  * < 0 - Error occurred (error is passed to user process)
1852  *
1853  * 0   - OK - proceed with automatic read or write.
1854  *
1855  * > 0 - OK - read or write has been done by the strategy routine, so
1856  *       return immediately.
1857  *
1858  * There must be a proc_handler routine for any terminal nodes
1859  * mirrored under /proc/sys (non-terminals are handled by a built-in
1860  * directory handler).  Several default handlers are available to
1861  * cover common cases -
1862  *
1863  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1864  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1865  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1866  *
1867  * It is the handler's job to read the input buffer from user memory
1868  * and process it. The handler should return 0 on success.
1869  *
1870  * This routine returns %NULL on a failure to register, and a pointer
1871  * to the table header on success.
1872  */
1873 struct ctl_table_header *__register_sysctl_paths(
1874         struct ctl_table_root *root,
1875         struct nsproxy *namespaces,
1876         const struct ctl_path *path, struct ctl_table *table)
1877 {
1878         struct ctl_table_header *header;
1879         struct ctl_table *new, **prevp;
1880         unsigned int n, npath;
1881         struct ctl_table_set *set;
1882
1883         /* Count the path components */
1884         for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
1885                 ;
1886
1887         /*
1888          * For each path component, allocate a 2-element ctl_table array.
1889          * The first array element will be filled with the sysctl entry
1890          * for this, the second will be the sentinel (ctl_name == 0).
1891          *
1892          * We allocate everything in one go so that we don't have to
1893          * worry about freeing additional memory in unregister_sysctl_table.
1894          */
1895         header = kzalloc(sizeof(struct ctl_table_header) +
1896                          (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1897         if (!header)
1898                 return NULL;
1899
1900         new = (struct ctl_table *) (header + 1);
1901
1902         /* Now connect the dots */
1903         prevp = &header->ctl_table;
1904         for (n = 0; n < npath; ++n, ++path) {
1905                 /* Copy the procname */
1906                 new->procname = path->procname;
1907                 new->ctl_name = path->ctl_name;
1908                 new->mode     = 0555;
1909
1910                 *prevp = new;
1911                 prevp = &new->child;
1912
1913                 new += 2;
1914         }
1915         *prevp = table;
1916         header->ctl_table_arg = table;
1917
1918         INIT_LIST_HEAD(&header->ctl_entry);
1919         header->used = 0;
1920         header->unregistering = NULL;
1921         header->root = root;
1922         sysctl_set_parent(NULL, header->ctl_table);
1923         header->count = 1;
1924 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1925         if (sysctl_check_table(namespaces, header->ctl_table)) {
1926                 kfree(header);
1927                 return NULL;
1928         }
1929 #endif
1930         spin_lock(&sysctl_lock);
1931         header->set = lookup_header_set(root, namespaces);
1932         header->attached_by = header->ctl_table;
1933         header->attached_to = root_table;
1934         header->parent = &root_table_header;
1935         for (set = header->set; set; set = set->parent) {
1936                 struct ctl_table_header *p;
1937                 list_for_each_entry(p, &set->list, ctl_entry) {
1938                         if (p->unregistering)
1939                                 continue;
1940                         try_attach(p, header);
1941                 }
1942         }
1943         header->parent->count++;
1944         list_add_tail(&header->ctl_entry, &header->set->list);
1945         spin_unlock(&sysctl_lock);
1946
1947         return header;
1948 }
1949
1950 /**
1951  * register_sysctl_table_path - register a sysctl table hierarchy
1952  * @path: The path to the directory the sysctl table is in.
1953  * @table: the top-level table structure
1954  *
1955  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1956  * array. A completely 0 filled entry terminates the table.
1957  *
1958  * See __register_sysctl_paths for more details.
1959  */
1960 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1961                                                 struct ctl_table *table)
1962 {
1963         return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1964                                         path, table);
1965 }
1966
1967 /**
1968  * register_sysctl_table - register a sysctl table hierarchy
1969  * @table: the top-level table structure
1970  *
1971  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1972  * array. A completely 0 filled entry terminates the table.
1973  *
1974  * See register_sysctl_paths for more details.
1975  */
1976 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1977 {
1978         static const struct ctl_path null_path[] = { {} };
1979
1980         return register_sysctl_paths(null_path, table);
1981 }
1982
1983 /**
1984  * unregister_sysctl_table - unregister a sysctl table hierarchy
1985  * @header: the header returned from register_sysctl_table
1986  *
1987  * Unregisters the sysctl table and all children. proc entries may not
1988  * actually be removed until they are no longer used by anyone.
1989  */
1990 void unregister_sysctl_table(struct ctl_table_header * header)
1991 {
1992         might_sleep();
1993
1994         if (header == NULL)
1995                 return;
1996
1997         spin_lock(&sysctl_lock);
1998         start_unregistering(header);
1999         if (!--header->parent->count) {
2000                 WARN_ON(1);
2001                 kfree(header->parent);
2002         }
2003         if (!--header->count)
2004                 kfree(header);
2005         spin_unlock(&sysctl_lock);
2006 }
2007
2008 int sysctl_is_seen(struct ctl_table_header *p)
2009 {
2010         struct ctl_table_set *set = p->set;
2011         int res;
2012         spin_lock(&sysctl_lock);
2013         if (p->unregistering)
2014                 res = 0;
2015         else if (!set->is_seen)
2016                 res = 1;
2017         else
2018                 res = set->is_seen(set);
2019         spin_unlock(&sysctl_lock);
2020         return res;
2021 }
2022
2023 void setup_sysctl_set(struct ctl_table_set *p,
2024         struct ctl_table_set *parent,
2025         int (*is_seen)(struct ctl_table_set *))
2026 {
2027         INIT_LIST_HEAD(&p->list);
2028         p->parent = parent ? parent : &sysctl_table_root.default_set;
2029         p->is_seen = is_seen;
2030 }
2031
2032 #else /* !CONFIG_SYSCTL */
2033 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2034 {
2035         return NULL;
2036 }
2037
2038 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2039                                                     struct ctl_table *table)
2040 {
2041         return NULL;
2042 }
2043
2044 void unregister_sysctl_table(struct ctl_table_header * table)
2045 {
2046 }
2047
2048 void setup_sysctl_set(struct ctl_table_set *p,
2049         struct ctl_table_set *parent,
2050         int (*is_seen)(struct ctl_table_set *))
2051 {
2052 }
2053
2054 void sysctl_head_put(struct ctl_table_header *head)
2055 {
2056 }
2057
2058 #endif /* CONFIG_SYSCTL */
2059
2060 /*
2061  * /proc/sys support
2062  */
2063
2064 #ifdef CONFIG_PROC_SYSCTL
2065
2066 static int _proc_do_string(void* data, int maxlen, int write,
2067                            struct file *filp, void __user *buffer,
2068                            size_t *lenp, loff_t *ppos)
2069 {
2070         size_t len;
2071         char __user *p;
2072         char c;
2073
2074         if (!data || !maxlen || !*lenp) {
2075                 *lenp = 0;
2076                 return 0;
2077         }
2078
2079         if (write) {
2080                 len = 0;
2081                 p = buffer;
2082                 while (len < *lenp) {
2083                         if (get_user(c, p++))
2084                                 return -EFAULT;
2085                         if (c == 0 || c == '\n')
2086                                 break;
2087                         len++;
2088                 }
2089                 if (len >= maxlen)
2090                         len = maxlen-1;
2091                 if(copy_from_user(data, buffer, len))
2092                         return -EFAULT;
2093                 ((char *) data)[len] = 0;
2094                 *ppos += *lenp;
2095         } else {
2096                 len = strlen(data);
2097                 if (len > maxlen)
2098                         len = maxlen;
2099
2100                 if (*ppos > len) {
2101                         *lenp = 0;
2102                         return 0;
2103                 }
2104
2105                 data += *ppos;
2106                 len  -= *ppos;
2107
2108                 if (len > *lenp)
2109                         len = *lenp;
2110                 if (len)
2111                         if(copy_to_user(buffer, data, len))
2112                                 return -EFAULT;
2113                 if (len < *lenp) {
2114                         if(put_user('\n', ((char __user *) buffer) + len))
2115                                 return -EFAULT;
2116                         len++;
2117                 }
2118                 *lenp = len;
2119                 *ppos += len;
2120         }
2121         return 0;
2122 }
2123
2124 /**
2125  * proc_dostring - read a string sysctl
2126  * @table: the sysctl table
2127  * @write: %TRUE if this is a write to the sysctl file
2128  * @filp: the file structure
2129  * @buffer: the user buffer
2130  * @lenp: the size of the user buffer
2131  * @ppos: file position
2132  *
2133  * Reads/writes a string from/to the user buffer. If the kernel
2134  * buffer provided is not large enough to hold the string, the
2135  * string is truncated. The copied string is %NULL-terminated.
2136  * If the string is being read by the user process, it is copied
2137  * and a newline '\n' is added. It is truncated if the buffer is
2138  * not large enough.
2139  *
2140  * Returns 0 on success.
2141  */
2142 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2143                   void __user *buffer, size_t *lenp, loff_t *ppos)
2144 {
2145         return _proc_do_string(table->data, table->maxlen, write, filp,
2146                                buffer, lenp, ppos);
2147 }
2148
2149
2150 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2151                                  int *valp,
2152                                  int write, void *data)
2153 {
2154         if (write) {
2155                 *valp = *negp ? -*lvalp : *lvalp;
2156         } else {
2157                 int val = *valp;
2158                 if (val < 0) {
2159                         *negp = -1;
2160                         *lvalp = (unsigned long)-val;
2161                 } else {
2162                         *negp = 0;
2163                         *lvalp = (unsigned long)val;
2164                 }
2165         }
2166         return 0;
2167 }
2168
2169 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2170                   int write, struct file *filp, void __user *buffer,
2171                   size_t *lenp, loff_t *ppos,
2172                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2173                               int write, void *data),
2174                   void *data)
2175 {
2176 #define TMPBUFLEN 21
2177         int *i, vleft, first=1, neg, val;
2178         unsigned long lval;
2179         size_t left, len;
2180
2181         char buf[TMPBUFLEN], *p;
2182         char __user *s = buffer;
2183
2184         if (!tbl_data || !table->maxlen || !*lenp ||
2185             (*ppos && !write)) {
2186                 *lenp = 0;
2187                 return 0;
2188         }
2189
2190         i = (int *) tbl_data;
2191         vleft = table->maxlen / sizeof(*i);
2192         left = *lenp;
2193
2194         if (!conv)
2195                 conv = do_proc_dointvec_conv;
2196
2197         for (; left && vleft--; i++, first=0) {
2198                 if (write) {
2199                         while (left) {
2200                                 char c;
2201                                 if (get_user(c, s))
2202                                         return -EFAULT;
2203                                 if (!isspace(c))
2204                                         break;
2205                                 left--;
2206                                 s++;
2207                         }
2208                         if (!left)
2209                                 break;
2210                         neg = 0;
2211                         len = left;
2212                         if (len > sizeof(buf) - 1)
2213                                 len = sizeof(buf) - 1;
2214                         if (copy_from_user(buf, s, len))
2215                                 return -EFAULT;
2216                         buf[len] = 0;
2217                         p = buf;
2218                         if (*p == '-' && left > 1) {
2219                                 neg = 1;
2220                                 p++;
2221                         }
2222                         if (*p < '0' || *p > '9')
2223                                 break;
2224
2225                         lval = simple_strtoul(p, &p, 0);
2226
2227                         len = p-buf;
2228                         if ((len < left) && *p && !isspace(*p))
2229                                 break;
2230                         if (neg)
2231                                 val = -val;
2232                         s += len;
2233                         left -= len;
2234
2235                         if (conv(&neg, &lval, i, 1, data))
2236                                 break;
2237                 } else {
2238                         p = buf;
2239                         if (!first)
2240                                 *p++ = '\t';
2241
2242                         if (conv(&neg, &lval, i, 0, data))
2243                                 break;
2244
2245                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
2246                         len = strlen(buf);
2247                         if (len > left)
2248                                 len = left;
2249                         if(copy_to_user(s, buf, len))
2250                                 return -EFAULT;
2251                         left -= len;
2252                         s += len;
2253                 }
2254         }
2255
2256         if (!write && !first && left) {
2257                 if(put_user('\n', s))
2258                         return -EFAULT;
2259                 left--, s++;
2260         }
2261         if (write) {
2262                 while (left) {
2263                         char c;
2264                         if (get_user(c, s++))
2265                                 return -EFAULT;
2266                         if (!isspace(c))
2267                                 break;
2268                         left--;
2269                 }
2270         }
2271         if (write && first)
2272                 return -EINVAL;
2273         *lenp -= left;
2274         *ppos += *lenp;
2275         return 0;
2276 #undef TMPBUFLEN
2277 }
2278
2279 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2280                   void __user *buffer, size_t *lenp, loff_t *ppos,
2281                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2282                               int write, void *data),
2283                   void *data)
2284 {
2285         return __do_proc_dointvec(table->data, table, write, filp,
2286                         buffer, lenp, ppos, conv, data);
2287 }
2288
2289 /**
2290  * proc_dointvec - read a vector of integers
2291  * @table: the sysctl table
2292  * @write: %TRUE if this is a write to the sysctl file
2293  * @filp: the file structure
2294  * @buffer: the user buffer
2295  * @lenp: the size of the user buffer
2296  * @ppos: file position
2297  *
2298  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2299  * values from/to the user buffer, treated as an ASCII string.
2300  *
2301  * Returns 0 on success.
2302  */
2303 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2304                      void __user *buffer, size_t *lenp, loff_t *ppos)
2305 {
2306     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2307                             NULL,NULL);
2308 }
2309
2310 /*
2311  * Taint values can only be increased
2312  * This means we can safely use a temporary.
2313  */
2314 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2315                                void __user *buffer, size_t *lenp, loff_t *ppos)
2316 {
2317         struct ctl_table t;
2318         unsigned long tmptaint = get_taint();
2319         int err;
2320
2321         if (write && !capable(CAP_SYS_ADMIN))
2322                 return -EPERM;
2323
2324         t = *table;
2325         t.data = &tmptaint;
2326         err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2327         if (err < 0)
2328                 return err;
2329
2330         if (write) {
2331                 /*
2332                  * Poor man's atomic or. Not worth adding a primitive
2333                  * to everyone's atomic.h for this
2334                  */
2335                 int i;
2336                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2337                         if ((tmptaint >> i) & 1)
2338                                 add_taint(i);
2339                 }
2340         }
2341
2342         return err;
2343 }
2344
2345 struct do_proc_dointvec_minmax_conv_param {
2346         int *min;
2347         int *max;
2348 };
2349
2350 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2351                                         int *valp,
2352                                         int write, void *data)
2353 {
2354         struct do_proc_dointvec_minmax_conv_param *param = data;
2355         if (write) {
2356                 int val = *negp ? -*lvalp : *lvalp;
2357                 if ((param->min && *param->min > val) ||
2358                     (param->max && *param->max < val))
2359                         return -EINVAL;
2360                 *valp = val;
2361         } else {
2362                 int val = *valp;
2363                 if (val < 0) {
2364                         *negp = -1;
2365                         *lvalp = (unsigned long)-val;
2366                 } else {
2367                         *negp = 0;
2368                         *lvalp = (unsigned long)val;
2369                 }
2370         }
2371         return 0;
2372 }
2373
2374 /**
2375  * proc_dointvec_minmax - read a vector of integers with min/max values
2376  * @table: the sysctl table
2377  * @write: %TRUE if this is a write to the sysctl file
2378  * @filp: the file structure
2379  * @buffer: the user buffer
2380  * @lenp: the size of the user buffer
2381  * @ppos: file position
2382  *
2383  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2384  * values from/to the user buffer, treated as an ASCII string.
2385  *
2386  * This routine will ensure the values are within the range specified by
2387  * table->extra1 (min) and table->extra2 (max).
2388  *
2389  * Returns 0 on success.
2390  */
2391 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2392                   void __user *buffer, size_t *lenp, loff_t *ppos)
2393 {
2394         struct do_proc_dointvec_minmax_conv_param param = {
2395                 .min = (int *) table->extra1,
2396                 .max = (int *) table->extra2,
2397         };
2398         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2399                                 do_proc_dointvec_minmax_conv, &param);
2400 }
2401
2402 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2403                                      struct file *filp,
2404                                      void __user *buffer,
2405                                      size_t *lenp, loff_t *ppos,
2406                                      unsigned long convmul,
2407                                      unsigned long convdiv)
2408 {
2409 #define TMPBUFLEN 21
2410         unsigned long *i, *min, *max, val;
2411         int vleft, first=1, neg;
2412         size_t len, left;
2413         char buf[TMPBUFLEN], *p;
2414         char __user *s = buffer;
2415
2416         if (!data || !table->maxlen || !*lenp ||
2417             (*ppos && !write)) {
2418                 *lenp = 0;
2419                 return 0;
2420         }
2421
2422         i = (unsigned long *) data;
2423         min = (unsigned long *) table->extra1;
2424         max = (unsigned long *) table->extra2;
2425         vleft = table->maxlen / sizeof(unsigned long);
2426         left = *lenp;
2427
2428         for (; left && vleft--; i++, min++, max++, first=0) {
2429                 if (write) {
2430                         while (left) {
2431                                 char c;
2432                                 if (get_user(c, s))
2433                                         return -EFAULT;
2434                                 if (!isspace(c))
2435                                         break;
2436                                 left--;
2437                                 s++;
2438                         }
2439                         if (!left)
2440                                 break;
2441                         neg = 0;
2442                         len = left;
2443                         if (len > TMPBUFLEN-1)
2444                                 len = TMPBUFLEN-1;
2445                         if (copy_from_user(buf, s, len))
2446                                 return -EFAULT;
2447                         buf[len] = 0;
2448                         p = buf;
2449                         if (*p == '-' && left > 1) {
2450                                 neg = 1;
2451                                 p++;
2452                         }
2453                         if (*p < '0' || *p > '9')
2454                                 break;
2455                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2456                         len = p-buf;
2457                         if ((len < left) && *p && !isspace(*p))
2458                                 break;
2459                         if (neg)
2460                                 val = -val;
2461                         s += len;
2462                         left -= len;
2463
2464                         if(neg)
2465                                 continue;
2466                         if ((min && val < *min) || (max && val > *max))
2467                                 continue;
2468                         *i = val;
2469                 } else {
2470                         p = buf;
2471                         if (!first)
2472                                 *p++ = '\t';
2473                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2474                         len = strlen(buf);
2475                         if (len > left)
2476                                 len = left;
2477                         if(copy_to_user(s, buf, len))
2478                                 return -EFAULT;
2479                         left -= len;
2480                         s += len;
2481                 }
2482         }
2483
2484         if (!write && !first && left) {
2485                 if(put_user('\n', s))
2486                         return -EFAULT;
2487                 left--, s++;
2488         }
2489         if (write) {
2490                 while (left) {
2491                         char c;
2492                         if (get_user(c, s++))
2493                                 return -EFAULT;
2494                         if (!isspace(c))
2495                                 break;
2496                         left--;
2497                 }
2498         }
2499         if (write && first)
2500                 return -EINVAL;
2501         *lenp -= left;
2502         *ppos += *lenp;
2503         return 0;
2504 #undef TMPBUFLEN
2505 }
2506
2507 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2508                                      struct file *filp,
2509                                      void __user *buffer,
2510                                      size_t *lenp, loff_t *ppos,
2511                                      unsigned long convmul,
2512                                      unsigned long convdiv)
2513 {
2514         return __do_proc_doulongvec_minmax(table->data, table, write,
2515                         filp, buffer, lenp, ppos, convmul, convdiv);
2516 }
2517
2518 /**
2519  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2520  * @table: the sysctl table
2521  * @write: %TRUE if this is a write to the sysctl file
2522  * @filp: the file structure
2523  * @buffer: the user buffer
2524  * @lenp: the size of the user buffer
2525  * @ppos: file position
2526  *
2527  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2528  * values from/to the user buffer, treated as an ASCII string.
2529  *
2530  * This routine will ensure the values are within the range specified by
2531  * table->extra1 (min) and table->extra2 (max).
2532  *
2533  * Returns 0 on success.
2534  */
2535 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2536                            void __user *buffer, size_t *lenp, loff_t *ppos)
2537 {
2538     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2539 }
2540
2541 /**
2542  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2543  * @table: the sysctl table
2544  * @write: %TRUE if this is a write to the sysctl file
2545  * @filp: the file structure
2546  * @buffer: the user buffer
2547  * @lenp: the size of the user buffer
2548  * @ppos: file position
2549  *
2550  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2551  * values from/to the user buffer, treated as an ASCII string. The values
2552  * are treated as milliseconds, and converted to jiffies when they are stored.
2553  *
2554  * This routine will ensure the values are within the range specified by
2555  * table->extra1 (min) and table->extra2 (max).
2556  *
2557  * Returns 0 on success.
2558  */
2559 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2560                                       struct file *filp,
2561                                       void __user *buffer,
2562                                       size_t *lenp, loff_t *ppos)
2563 {
2564     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2565                                      lenp, ppos, HZ, 1000l);
2566 }
2567
2568
2569 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2570                                          int *valp,
2571                                          int write, void *data)
2572 {
2573         if (write) {
2574                 if (*lvalp > LONG_MAX / HZ)
2575                         return 1;
2576                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2577         } else {
2578                 int val = *valp;
2579                 unsigned long lval;
2580                 if (val < 0) {
2581                         *negp = -1;
2582                         lval = (unsigned long)-val;
2583                 } else {
2584                         *negp = 0;
2585                         lval = (unsigned long)val;
2586                 }
2587                 *lvalp = lval / HZ;
2588         }
2589         return 0;
2590 }
2591
2592 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2593                                                 int *valp,
2594                                                 int write, void *data)
2595 {
2596         if (write) {
2597                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2598                         return 1;
2599                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2600         } else {
2601                 int val = *valp;
2602                 unsigned long lval;
2603                 if (val < 0) {
2604                         *negp = -1;
2605                         lval = (unsigned long)-val;
2606                 } else {
2607                         *negp = 0;
2608                         lval = (unsigned long)val;
2609                 }
2610                 *lvalp = jiffies_to_clock_t(lval);
2611         }
2612         return 0;
2613 }
2614
2615 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2616                                             int *valp,
2617                                             int write, void *data)
2618 {
2619         if (write) {
2620                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2621         } else {
2622                 int val = *valp;
2623                 unsigned long lval;
2624                 if (val < 0) {
2625                         *negp = -1;
2626                         lval = (unsigned long)-val;
2627                 } else {
2628                         *negp = 0;
2629                         lval = (unsigned long)val;
2630                 }
2631                 *lvalp = jiffies_to_msecs(lval);
2632         }
2633         return 0;
2634 }
2635
2636 /**
2637  * proc_dointvec_jiffies - read a vector of integers as seconds
2638  * @table: the sysctl table
2639  * @write: %TRUE if this is a write to the sysctl file
2640  * @filp: the file structure
2641  * @buffer: the user buffer
2642  * @lenp: the size of the user buffer
2643  * @ppos: file position
2644  *
2645  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2646  * values from/to the user buffer, treated as an ASCII string.
2647  * The values read are assumed to be in seconds, and are converted into
2648  * jiffies.
2649  *
2650  * Returns 0 on success.
2651  */
2652 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2653                           void __user *buffer, size_t *lenp, loff_t *ppos)
2654 {
2655     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2656                             do_proc_dointvec_jiffies_conv,NULL);
2657 }
2658
2659 /**
2660  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2661  * @table: the sysctl table
2662  * @write: %TRUE if this is a write to the sysctl file
2663  * @filp: the file structure
2664  * @buffer: the user buffer
2665  * @lenp: the size of the user buffer
2666  * @ppos: pointer to the file position
2667  *
2668  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2669  * values from/to the user buffer, treated as an ASCII string.
2670  * The values read are assumed to be in 1/USER_HZ seconds, and
2671  * are converted into jiffies.
2672  *
2673  * Returns 0 on success.
2674  */
2675 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2676                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2677 {
2678     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2679                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2680 }
2681
2682 /**
2683  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2684  * @table: the sysctl table
2685  * @write: %TRUE if this is a write to the sysctl file
2686  * @filp: the file structure
2687  * @buffer: the user buffer
2688  * @lenp: the size of the user buffer
2689  * @ppos: file position
2690  * @ppos: the current position in the file
2691  *
2692  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2693  * values from/to the user buffer, treated as an ASCII string.
2694  * The values read are assumed to be in 1/1000 seconds, and
2695  * are converted into jiffies.
2696  *
2697  * Returns 0 on success.
2698  */
2699 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2700                              void __user *buffer, size_t *lenp, loff_t *ppos)
2701 {
2702         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2703                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2704 }
2705
2706 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2707                            void __user *buffer, size_t *lenp, loff_t *ppos)
2708 {
2709         struct pid *new_pid;
2710         pid_t tmp;
2711         int r;
2712
2713         tmp = pid_vnr(cad_pid);
2714
2715         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2716                                lenp, ppos, NULL, NULL);
2717         if (r || !write)
2718                 return r;
2719
2720         new_pid = find_get_pid(tmp);
2721         if (!new_pid)
2722                 return -ESRCH;
2723
2724         put_pid(xchg(&cad_pid, new_pid));
2725         return 0;
2726 }
2727
2728 #else /* CONFIG_PROC_FS */
2729
2730 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2731                   void __user *buffer, size_t *lenp, loff_t *ppos)
2732 {
2733         return -ENOSYS;
2734 }
2735
2736 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2737                   void __user *buffer, size_t *lenp, loff_t *ppos)
2738 {
2739         return -ENOSYS;
2740 }
2741
2742 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2743                     void __user *buffer, size_t *lenp, loff_t *ppos)
2744 {
2745         return -ENOSYS;
2746 }
2747
2748 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2749                     void __user *buffer, size_t *lenp, loff_t *ppos)
2750 {
2751         return -ENOSYS;
2752 }
2753
2754 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2755                     void __user *buffer, size_t *lenp, loff_t *ppos)
2756 {
2757         return -ENOSYS;
2758 }
2759
2760 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2761                              void __user *buffer, size_t *lenp, loff_t *ppos)
2762 {
2763         return -ENOSYS;
2764 }
2765
2766 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2767                     void __user *buffer, size_t *lenp, loff_t *ppos)
2768 {
2769         return -ENOSYS;
2770 }
2771
2772 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2773                                       struct file *filp,
2774                                       void __user *buffer,
2775                                       size_t *lenp, loff_t *ppos)
2776 {
2777     return -ENOSYS;
2778 }
2779
2780
2781 #endif /* CONFIG_PROC_FS */
2782
2783
2784 #ifdef CONFIG_SYSCTL_SYSCALL
2785 /*
2786  * General sysctl support routines
2787  */
2788
2789 /* The generic sysctl data routine (used if no strategy routine supplied) */
2790 int sysctl_data(struct ctl_table *table,
2791                 void __user *oldval, size_t __user *oldlenp,
2792                 void __user *newval, size_t newlen)
2793 {
2794         size_t len;
2795
2796         /* Get out of I don't have a variable */
2797         if (!table->data || !table->maxlen)
2798                 return -ENOTDIR;
2799
2800         if (oldval && oldlenp) {
2801                 if (get_user(len, oldlenp))
2802                         return -EFAULT;
2803                 if (len) {
2804                         if (len > table->maxlen)
2805                                 len = table->maxlen;
2806                         if (copy_to_user(oldval, table->data, len))
2807                                 return -EFAULT;
2808                         if (put_user(len, oldlenp))
2809                                 return -EFAULT;
2810                 }
2811         }
2812
2813         if (newval && newlen) {
2814                 if (newlen > table->maxlen)
2815                         newlen = table->maxlen;
2816
2817                 if (copy_from_user(table->data, newval, newlen))
2818                         return -EFAULT;
2819         }
2820         return 1;
2821 }
2822
2823 /* The generic string strategy routine: */
2824 int sysctl_string(struct ctl_table *table,
2825                   void __user *oldval, size_t __user *oldlenp,
2826                   void __user *newval, size_t newlen)
2827 {
2828         if (!table->data || !table->maxlen)
2829                 return -ENOTDIR;
2830
2831         if (oldval && oldlenp) {
2832                 size_t bufsize;
2833                 if (get_user(bufsize, oldlenp))
2834                         return -EFAULT;
2835                 if (bufsize) {
2836                         size_t len = strlen(table->data), copied;
2837
2838                         /* This shouldn't trigger for a well-formed sysctl */
2839                         if (len > table->maxlen)
2840                                 len = table->maxlen;
2841
2842                         /* Copy up to a max of bufsize-1 bytes of the string */
2843                         copied = (len >= bufsize) ? bufsize - 1 : len;
2844
2845                         if (copy_to_user(oldval, table->data, copied) ||
2846                             put_user(0, (char __user *)(oldval + copied)))
2847                                 return -EFAULT;
2848                         if (put_user(len, oldlenp))
2849                                 return -EFAULT;
2850                 }
2851         }
2852         if (newval && newlen) {
2853                 size_t len = newlen;
2854                 if (len > table->maxlen)
2855                         len = table->maxlen;
2856                 if(copy_from_user(table->data, newval, len))
2857                         return -EFAULT;
2858                 if (len == table->maxlen)
2859                         len--;
2860                 ((char *) table->data)[len] = 0;
2861         }
2862         return 1;
2863 }
2864
2865 /*
2866  * This function makes sure that all of the integers in the vector
2867  * are between the minimum and maximum values given in the arrays
2868  * table->extra1 and table->extra2, respectively.
2869  */
2870 int sysctl_intvec(struct ctl_table *table,
2871                 void __user *oldval, size_t __user *oldlenp,
2872                 void __user *newval, size_t newlen)
2873 {
2874
2875         if (newval && newlen) {
2876                 int __user *vec = (int __user *) newval;
2877                 int *min = (int *) table->extra1;
2878                 int *max = (int *) table->extra2;
2879                 size_t length;
2880                 int i;
2881
2882                 if (newlen % sizeof(int) != 0)
2883                         return -EINVAL;
2884
2885                 if (!table->extra1 && !table->extra2)
2886                         return 0;
2887
2888                 if (newlen > table->maxlen)
2889                         newlen = table->maxlen;
2890                 length = newlen / sizeof(int);
2891
2892                 for (i = 0; i < length; i++) {
2893                         int value;
2894                         if (get_user(value, vec + i))
2895                                 return -EFAULT;
2896                         if (min && value < min[i])
2897                                 return -EINVAL;
2898                         if (max && value > max[i])
2899                                 return -EINVAL;
2900                 }
2901         }
2902         return 0;
2903 }
2904
2905 /* Strategy function to convert jiffies to seconds */
2906 int sysctl_jiffies(struct ctl_table *table,
2907                 void __user *oldval, size_t __user *oldlenp,
2908                 void __user *newval, size_t newlen)
2909 {
2910         if (oldval && oldlenp) {
2911                 size_t olen;
2912
2913                 if (get_user(olen, oldlenp))
2914                         return -EFAULT;
2915                 if (olen) {
2916                         int val;
2917
2918                         if (olen < sizeof(int))
2919                                 return -EINVAL;
2920
2921                         val = *(int *)(table->data) / HZ;
2922                         if (put_user(val, (int __user *)oldval))
2923                                 return -EFAULT;
2924                         if (put_user(sizeof(int), oldlenp))
2925                                 return -EFAULT;
2926                 }
2927         }
2928         if (newval && newlen) {
2929                 int new;
2930                 if (newlen != sizeof(int))
2931                         return -EINVAL;
2932                 if (get_user(new, (int __user *)newval))
2933                         return -EFAULT;
2934                 *(int *)(table->data) = new*HZ;
2935         }
2936         return 1;
2937 }
2938
2939 /* Strategy function to convert jiffies to seconds */
2940 int sysctl_ms_jiffies(struct ctl_table *table,
2941                 void __user *oldval, size_t __user *oldlenp,
2942                 void __user *newval, size_t newlen)
2943 {
2944         if (oldval && oldlenp) {
2945                 size_t olen;
2946
2947                 if (get_user(olen, oldlenp))
2948                         return -EFAULT;
2949                 if (olen) {
2950                         int val;
2951
2952                         if (olen < sizeof(int))
2953                                 return -EINVAL;
2954
2955                         val = jiffies_to_msecs(*(int *)(table->data));
2956                         if (put_user(val, (int __user *)oldval))
2957                                 return -EFAULT;
2958                         if (put_user(sizeof(int), oldlenp))
2959                                 return -EFAULT;
2960                 }
2961         }
2962         if (newval && newlen) {
2963                 int new;
2964                 if (newlen != sizeof(int))
2965                         return -EINVAL;
2966                 if (get_user(new, (int __user *)newval))
2967                         return -EFAULT;
2968                 *(int *)(table->data) = msecs_to_jiffies(new);
2969         }
2970         return 1;
2971 }
2972
2973
2974
2975 #else /* CONFIG_SYSCTL_SYSCALL */
2976
2977
2978 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2979 {
2980         struct __sysctl_args tmp;
2981         int error;
2982
2983         if (copy_from_user(&tmp, args, sizeof(tmp)))
2984                 return -EFAULT;
2985
2986         error = deprecated_sysctl_warning(&tmp);
2987
2988         /* If no error reading the parameters then just -ENOSYS ... */
2989         if (!error)
2990                 error = -ENOSYS;
2991
2992         return error;
2993 }
2994
2995 int sysctl_data(struct ctl_table *table,
2996                   void __user *oldval, size_t __user *oldlenp,
2997                   void __user *newval, size_t newlen)
2998 {
2999         return -ENOSYS;
3000 }
3001
3002 int sysctl_string(struct ctl_table *table,
3003                   void __user *oldval, size_t __user *oldlenp,
3004                   void __user *newval, size_t newlen)
3005 {
3006         return -ENOSYS;
3007 }
3008
3009 int sysctl_intvec(struct ctl_table *table,
3010                 void __user *oldval, size_t __user *oldlenp,
3011                 void __user *newval, size_t newlen)
3012 {
3013         return -ENOSYS;
3014 }
3015
3016 int sysctl_jiffies(struct ctl_table *table,
3017                 void __user *oldval, size_t __user *oldlenp,
3018                 void __user *newval, size_t newlen)
3019 {
3020         return -ENOSYS;
3021 }
3022
3023 int sysctl_ms_jiffies(struct ctl_table *table,
3024                 void __user *oldval, size_t __user *oldlenp,
3025                 void __user *newval, size_t newlen)
3026 {
3027         return -ENOSYS;
3028 }
3029
3030 #endif /* CONFIG_SYSCTL_SYSCALL */
3031
3032 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3033 {
3034         static int msg_count;
3035         int name[CTL_MAXNAME];
3036         int i;
3037
3038         /* Check args->nlen. */
3039         if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3040                 return -ENOTDIR;
3041
3042         /* Read in the sysctl name for better debug message logging */
3043         for (i = 0; i < args->nlen; i++)
3044                 if (get_user(name[i], args->name + i))
3045                         return -EFAULT;
3046
3047         /* Ignore accesses to kernel.version */
3048         if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3049                 return 0;
3050
3051         if (msg_count < 5) {
3052                 msg_count++;
3053                 printk(KERN_INFO
3054                         "warning: process `%s' used the deprecated sysctl "
3055                         "system call with ", current->comm);
3056                 for (i = 0; i < args->nlen; i++)
3057                         printk("%d.", name[i]);
3058                 printk("\n");
3059         }
3060         return 0;
3061 }
3062
3063 /*
3064  * No sense putting this after each symbol definition, twice,
3065  * exception granted :-)
3066  */
3067 EXPORT_SYMBOL(proc_dointvec);
3068 EXPORT_SYMBOL(proc_dointvec_jiffies);
3069 EXPORT_SYMBOL(proc_dointvec_minmax);
3070 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3071 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3072 EXPORT_SYMBOL(proc_dostring);
3073 EXPORT_SYMBOL(proc_doulongvec_minmax);
3074 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3075 EXPORT_SYMBOL(register_sysctl_table);
3076 EXPORT_SYMBOL(register_sysctl_paths);
3077 EXPORT_SYMBOL(sysctl_intvec);
3078 EXPORT_SYMBOL(sysctl_jiffies);
3079 EXPORT_SYMBOL(sysctl_ms_jiffies);
3080 EXPORT_SYMBOL(sysctl_string);
3081 EXPORT_SYMBOL(sysctl_data);
3082 EXPORT_SYMBOL(unregister_sysctl_table);