kernel/sysctl.c

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