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