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

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/mm.h>
  23 #include <linux/swap.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/security.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/smp_lock.h>
  31 #include <linux/fs.h>
  32 #include <linux/init.h>
  33 #include <linux/kernel.h>
  34 #include <linux/kobject.h>
  35 #include <linux/net.h>
  36 #include <linux/sysrq.h>
  37 #include <linux/highuid.h>
  38 #include <linux/writeback.h>
  39 #include <linux/hugetlb.h>
  40 #include <linux/initrd.h>
  41 #include <linux/key.h>
  42 #include <linux/times.h>
  43 #include <linux/limits.h>
  44 #include <linux/dcache.h>
  45 #include <linux/syscalls.h>
  46 #include <linux/vmstat.h>
  47 #include <linux/nfs_fs.h>
  48 #include <linux/acpi.h>
  49 #include <linux/reboot.h>
  50 #include <linux/ftrace.h>
  51
  52 #include <asm/uaccess.h>
  53 #include <asm/processor.h>
  54
  55 #ifdef CONFIG_X86
  56 #include <asm/nmi.h>
  57 #include <asm/stacktrace.h>
  58 #include <asm/io.h>
  59 #endif
  60
  61 static int deprecated_sysctl_warning(struct __sysctl_args *args);
  62
  63 #if defined(CONFIG_SYSCTL)
  64
  65 /* External variables not in a header file. */
  66 extern int C_A_D;
  67 extern int print_fatal_signals;
  68 extern int sysctl_overcommit_memory;
  69 extern int sysctl_overcommit_ratio;
  70 extern int sysctl_panic_on_oom;
  71 extern int sysctl_oom_kill_allocating_task;
  72 extern int sysctl_oom_dump_tasks;
  73 extern int max_threads;
  74 extern int core_uses_pid;
  75 extern int suid_dumpable;
  76 extern char core_pattern[];
  77 extern int pid_max;
  78 extern int min_free_kbytes;
  79 extern int pid_max_min, pid_max_max;
  80 extern int sysctl_drop_caches;
  81 extern int percpu_pagelist_fraction;
  82 extern int compat_log;
  83 extern int maps_protect;
  84 extern int latencytop_enabled;
  85 extern int sysctl_nr_open_min, sysctl_nr_open_max;
  86 #ifdef CONFIG_RCU_TORTURE_TEST
  87 extern int rcutorture_runnable;
  88 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
  89
  90 /* Constants used for minimum and  maximum */
  91 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_DETECT_SOFTLOCKUP)
  92 static int one = 1;
  93 #endif
  94
  95 #ifdef CONFIG_DETECT_SOFTLOCKUP
  96 static int sixty = 60;
  97 static int neg_one = -1;
  98 #endif
  99
 100 #ifdef CONFIG_MMU
 101 static int two = 2;
 102 #endif
 103
 104 static int zero;
 105 static int one_hundred = 100;
 106
 107 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 108 static int maxolduid = 65535;
 109 static int minolduid;
 110 static int min_percpu_pagelist_fract = 8;
 111
 112 static int ngroups_max = NGROUPS_MAX;
 113
 114 #ifdef CONFIG_MODULES
 115 extern char modprobe_path[];
 116 #endif
 117 #ifdef CONFIG_CHR_DEV_SG
 118 extern int sg_big_buff;
 119 #endif
 120
 121 #ifdef __sparc__
 122 extern char reboot_command [];
 123 extern int stop_a_enabled;
 124 extern int scons_pwroff;
 125 #endif
 126
 127 #ifdef __hppa__
 128 extern int pwrsw_enabled;
 129 extern int unaligned_enabled;
 130 #endif
 131
 132 #ifdef CONFIG_S390
 133 #ifdef CONFIG_MATHEMU
 134 extern int sysctl_ieee_emulation_warnings;
 135 #endif
 136 extern int sysctl_userprocess_debug;
 137 extern int spin_retry;
 138 #endif
 139
 140 #ifdef CONFIG_BSD_PROCESS_ACCT
 141 extern int acct_parm[];
 142 #endif
 143
 144 #ifdef CONFIG_IA64
 145 extern int no_unaligned_warning;
 146 #endif
 147
 148 #ifdef CONFIG_RT_MUTEXES
 149 extern int max_lock_depth;
 150 #endif
 151
 152 #ifdef CONFIG_PROC_SYSCTL
 153 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
 154                   void __user *buffer, size_t *lenp, loff_t *ppos);
 155 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
 156                                void __user *buffer, size_t *lenp, loff_t *ppos);
 157 #endif
 158
 159 static struct ctl_table root_table[];
 160 static struct ctl_table_root sysctl_table_root;
 161 static struct ctl_table_header root_table_header = {
 162         .ctl_table = root_table,
 163         .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
 164         .root = &sysctl_table_root,
 165         .set = &sysctl_table_root.default_set,
 166 };
 167 static struct ctl_table_root sysctl_table_root = {
 168         .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
 169         .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
 170 };
 171
 172 static struct ctl_table kern_table[];
 173 static struct ctl_table vm_table[];
 174 static struct ctl_table fs_table[];
 175 static struct ctl_table debug_table[];
 176 static struct ctl_table dev_table[];
 177 extern struct ctl_table random_table[];
 178 #ifdef CONFIG_INOTIFY_USER
 179 extern struct ctl_table inotify_table[];
 180 #endif
 181
 182 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 183 int sysctl_legacy_va_layout;
 184 #endif
 185
 186 extern int prove_locking;
 187 extern int lock_stat;
 188
 189 /* The default sysctl tables: */
 190
 191 static struct ctl_table root_table[] = {
 192         {
 193                 .ctl_name       = CTL_KERN,
 194                 .procname       = "kernel",
 195                 .mode           = 0555,
 196                 .child          = kern_table,
 197         },
 198         {
 199                 .ctl_name       = CTL_VM,
 200                 .procname       = "vm",
 201                 .mode           = 0555,
 202                 .child          = vm_table,
 203         },
 204         {
 205                 .ctl_name       = CTL_FS,
 206                 .procname       = "fs",
 207                 .mode           = 0555,
 208                 .child          = fs_table,
 209         },
 210         {
 211                 .ctl_name       = CTL_DEBUG,
 212                 .procname       = "debug",
 213                 .mode           = 0555,
 214                 .child          = debug_table,
 215         },
 216         {
 217                 .ctl_name       = CTL_DEV,
 218                 .procname       = "dev",
 219                 .mode           = 0555,
 220                 .child          = dev_table,
 221         },
 222 /*
 223  * NOTE: do not add new entries to this table unless you have read
 224  * Documentation/sysctl/ctl_unnumbered.txt
 225  */
 226         { .ctl_name = 0 }
 227 };
 228
 229 #ifdef CONFIG_SCHED_DEBUG
 230 static int min_sched_granularity_ns = 100000;           /* 100 usecs */
 231 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
 232 static int min_wakeup_granularity_ns;                   /* 0 usecs */
 233 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
 234 #endif
 235
 236 static struct ctl_table kern_table[] = {
 237 #ifdef CONFIG_SCHED_DEBUG
 238         {
 239                 .ctl_name       = CTL_UNNUMBERED,
 240                 .procname       = "sched_min_granularity_ns",
 241                 .data           = &sysctl_sched_min_granularity,
 242                 .maxlen         = sizeof(unsigned int),
 243                 .mode           = 0644,
 244                 .proc_handler   = &sched_nr_latency_handler,
 245                 .strategy       = &sysctl_intvec,
 246                 .extra1         = &min_sched_granularity_ns,
 247                 .extra2         = &max_sched_granularity_ns,
 248         },
 249         {
 250                 .ctl_name       = CTL_UNNUMBERED,
 251                 .procname       = "sched_latency_ns",
 252                 .data           = &sysctl_sched_latency,
 253                 .maxlen         = sizeof(unsigned int),
 254                 .mode           = 0644,
 255                 .proc_handler   = &sched_nr_latency_handler,
 256                 .strategy       = &sysctl_intvec,
 257                 .extra1         = &min_sched_granularity_ns,
 258                 .extra2         = &max_sched_granularity_ns,
 259         },
 260         {
 261                 .ctl_name       = CTL_UNNUMBERED,
 262                 .procname       = "sched_wakeup_granularity_ns",
 263                 .data           = &sysctl_sched_wakeup_granularity,
 264                 .maxlen         = sizeof(unsigned int),
 265                 .mode           = 0644,
 266                 .proc_handler   = &proc_dointvec_minmax,
 267                 .strategy       = &sysctl_intvec,
 268                 .extra1         = &min_wakeup_granularity_ns,
 269                 .extra2         = &max_wakeup_granularity_ns,
 270         },
 271         {
 272                 .ctl_name       = CTL_UNNUMBERED,
 273                 .procname       = "sched_shares_ratelimit",
 274                 .data           = &sysctl_sched_shares_ratelimit,
 275                 .maxlen         = sizeof(unsigned int),
 276                 .mode           = 0644,
 277                 .proc_handler   = &proc_dointvec,
 278         },
 279         {
 280                 .ctl_name       = CTL_UNNUMBERED,
 281                 .procname       = "sched_child_runs_first",
 282                 .data           = &sysctl_sched_child_runs_first,
 283                 .maxlen         = sizeof(unsigned int),
 284                 .mode           = 0644,
 285                 .proc_handler   = &proc_dointvec,
 286         },
 287         {
 288                 .ctl_name       = CTL_UNNUMBERED,
 289                 .procname       = "sched_features",
 290                 .data           = &sysctl_sched_features,
 291                 .maxlen         = sizeof(unsigned int),
 292                 .mode           = 0644,
 293                 .proc_handler   = &proc_dointvec,
 294         },
 295         {
 296                 .ctl_name       = CTL_UNNUMBERED,
 297                 .procname       = "sched_migration_cost",
 298                 .data           = &sysctl_sched_migration_cost,
 299                 .maxlen         = sizeof(unsigned int),
 300                 .mode           = 0644,
 301                 .proc_handler   = &proc_dointvec,
 302         },
 303         {
 304                 .ctl_name       = CTL_UNNUMBERED,
 305                 .procname       = "sched_nr_migrate",
 306                 .data           = &sysctl_sched_nr_migrate,
 307                 .maxlen         = sizeof(unsigned int),
 308                 .mode           = 0644,
 309                 .proc_handler   = &proc_dointvec,
 310         },
 311 #endif
 312         {
 313                 .ctl_name       = CTL_UNNUMBERED,
 314                 .procname       = "sched_rt_period_us",
 315                 .data           = &sysctl_sched_rt_period,
 316                 .maxlen         = sizeof(unsigned int),
 317                 .mode           = 0644,
 318                 .proc_handler   = &sched_rt_handler,
 319         },
 320         {
 321                 .ctl_name       = CTL_UNNUMBERED,
 322                 .procname       = "sched_rt_runtime_us",
 323                 .data           = &sysctl_sched_rt_runtime,
 324                 .maxlen         = sizeof(int),
 325                 .mode           = 0644,
 326                 .proc_handler   = &sched_rt_handler,
 327         },
 328         {
 329                 .ctl_name       = CTL_UNNUMBERED,
 330                 .procname       = "sched_compat_yield",
 331                 .data           = &sysctl_sched_compat_yield,
 332                 .maxlen         = sizeof(unsigned int),
 333                 .mode           = 0644,
 334                 .proc_handler   = &proc_dointvec,
 335         },
 336 #ifdef CONFIG_PROVE_LOCKING
 337         {
 338                 .ctl_name       = CTL_UNNUMBERED,
 339                 .procname       = "prove_locking",
 340                 .data           = &prove_locking,
 341                 .maxlen         = sizeof(int),
 342                 .mode           = 0644,
 343                 .proc_handler   = &proc_dointvec,
 344         },
 345 #endif
 346 #ifdef CONFIG_LOCK_STAT
 347         {
 348                 .ctl_name       = CTL_UNNUMBERED,
 349                 .procname       = "lock_stat",
 350                 .data           = &lock_stat,
 351                 .maxlen         = sizeof(int),
 352                 .mode           = 0644,
 353                 .proc_handler   = &proc_dointvec,
 354         },
 355 #endif
 356         {
 357                 .ctl_name       = KERN_PANIC,
 358                 .procname       = "panic",
 359                 .data           = &panic_timeout,
 360                 .maxlen         = sizeof(int),
 361                 .mode           = 0644,
 362                 .proc_handler   = &proc_dointvec,
 363         },
 364         {
 365                 .ctl_name       = KERN_CORE_USES_PID,
 366                 .procname       = "core_uses_pid",
 367                 .data           = &core_uses_pid,
 368                 .maxlen         = sizeof(int),
 369                 .mode           = 0644,
 370                 .proc_handler   = &proc_dointvec,
 371         },
 372         {
 373                 .ctl_name       = KERN_CORE_PATTERN,
 374                 .procname       = "core_pattern",
 375                 .data           = core_pattern,
 376                 .maxlen         = CORENAME_MAX_SIZE,
 377                 .mode           = 0644,
 378                 .proc_handler   = &proc_dostring,
 379                 .strategy       = &sysctl_string,
 380         },
 381 #ifdef CONFIG_PROC_SYSCTL
 382         {
 383                 .procname       = "tainted",
 384                 .data           = &tainted,
 385                 .maxlen         = sizeof(int),
 386                 .mode           = 0644,
 387                 .proc_handler   = &proc_dointvec_taint,
 388         },
 389 #endif
 390 #ifdef CONFIG_LATENCYTOP
 391         {
 392                 .procname       = "latencytop",
 393                 .data           = &latencytop_enabled,
 394                 .maxlen         = sizeof(int),
 395                 .mode           = 0644,
 396                 .proc_handler   = &proc_dointvec,
 397         },
 398 #endif
 399 #ifdef CONFIG_BLK_DEV_INITRD
 400         {
 401                 .ctl_name       = KERN_REALROOTDEV,
 402                 .procname       = "real-root-dev",
 403                 .data           = &real_root_dev,
 404                 .maxlen         = sizeof(int),
 405                 .mode           = 0644,
 406                 .proc_handler   = &proc_dointvec,
 407         },
 408 #endif
 409         {
 410                 .ctl_name       = CTL_UNNUMBERED,
 411                 .procname       = "print-fatal-signals",
 412                 .data           = &print_fatal_signals,
 413                 .maxlen         = sizeof(int),
 414                 .mode           = 0644,
 415                 .proc_handler   = &proc_dointvec,
 416         },
 417 #ifdef __sparc__
 418         {
 419                 .ctl_name       = KERN_SPARC_REBOOT,
 420                 .procname       = "reboot-cmd",
 421                 .data           = reboot_command,
 422                 .maxlen         = 256,
 423                 .mode           = 0644,
 424                 .proc_handler   = &proc_dostring,
 425                 .strategy       = &sysctl_string,
 426         },
 427         {
 428                 .ctl_name       = KERN_SPARC_STOP_A,
 429                 .procname       = "stop-a",
 430                 .data           = &stop_a_enabled,
 431                 .maxlen         = sizeof (int),
 432                 .mode           = 0644,
 433                 .proc_handler   = &proc_dointvec,
 434         },
 435         {
 436                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 437                 .procname       = "scons-poweroff",
 438                 .data           = &scons_pwroff,
 439                 .maxlen         = sizeof (int),
 440                 .mode           = 0644,
 441                 .proc_handler   = &proc_dointvec,
 442         },
 443 #endif
 444 #ifdef __hppa__
 445         {
 446                 .ctl_name       = KERN_HPPA_PWRSW,
 447                 .procname       = "soft-power",
 448                 .data           = &pwrsw_enabled,
 449                 .maxlen         = sizeof (int),
 450                 .mode           = 0644,
 451                 .proc_handler   = &proc_dointvec,
 452         },
 453         {
 454                 .ctl_name       = KERN_HPPA_UNALIGNED,
 455                 .procname       = "unaligned-trap",
 456                 .data           = &unaligned_enabled,
 457                 .maxlen         = sizeof (int),
 458                 .mode           = 0644,
 459                 .proc_handler   = &proc_dointvec,
 460         },
 461 #endif
 462         {
 463                 .ctl_name       = KERN_CTLALTDEL,
 464                 .procname       = "ctrl-alt-del",
 465                 .data           = &C_A_D,
 466                 .maxlen         = sizeof(int),
 467                 .mode           = 0644,
 468                 .proc_handler   = &proc_dointvec,
 469         },
 470 #ifdef CONFIG_FTRACE
 471         {
 472                 .ctl_name       = CTL_UNNUMBERED,
 473                 .procname       = "ftrace_enabled",
 474                 .data           = &ftrace_enabled,
 475                 .maxlen         = sizeof(int),
 476                 .mode           = 0644,
 477                 .proc_handler   = &ftrace_enable_sysctl,
 478         },
 479 #endif
 480 #ifdef CONFIG_MODULES
 481         {
 482                 .ctl_name       = KERN_MODPROBE,
 483                 .procname       = "modprobe",
 484                 .data           = &modprobe_path,
 485                 .maxlen         = KMOD_PATH_LEN,
 486                 .mode           = 0644,
 487                 .proc_handler   = &proc_dostring,
 488                 .strategy       = &sysctl_string,
 489         },
 490 #endif
 491 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 492         {
 493                 .ctl_name       = KERN_HOTPLUG,
 494                 .procname       = "hotplug",
 495                 .data           = &uevent_helper,
 496                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 497                 .mode           = 0644,
 498                 .proc_handler   = &proc_dostring,
 499                 .strategy       = &sysctl_string,
 500         },
 501 #endif
 502 #ifdef CONFIG_CHR_DEV_SG
 503         {
 504                 .ctl_name       = KERN_SG_BIG_BUFF,
 505                 .procname       = "sg-big-buff",
 506                 .data           = &sg_big_buff,
 507                 .maxlen         = sizeof (int),
 508                 .mode           = 0444,
 509                 .proc_handler   = &proc_dointvec,
 510         },
 511 #endif
 512 #ifdef CONFIG_BSD_PROCESS_ACCT
 513         {
 514                 .ctl_name       = KERN_ACCT,
 515                 .procname       = "acct",
 516                 .data           = &acct_parm,
 517                 .maxlen         = 3*sizeof(int),
 518                 .mode           = 0644,
 519                 .proc_handler   = &proc_dointvec,
 520         },
 521 #endif
 522 #ifdef CONFIG_MAGIC_SYSRQ
 523         {
 524                 .ctl_name       = KERN_SYSRQ,
 525                 .procname       = "sysrq",
 526                 .data           = &__sysrq_enabled,
 527                 .maxlen         = sizeof (int),
 528                 .mode           = 0644,
 529                 .proc_handler   = &proc_dointvec,
 530         },
 531 #endif
 532 #ifdef CONFIG_PROC_SYSCTL
 533         {
 534                 .procname       = "cad_pid",
 535                 .data           = NULL,
 536                 .maxlen         = sizeof (int),
 537                 .mode           = 0600,
 538                 .proc_handler   = &proc_do_cad_pid,
 539         },
 540 #endif
 541         {
 542                 .ctl_name       = KERN_MAX_THREADS,
 543                 .procname       = "threads-max",
 544                 .data           = &max_threads,
 545                 .maxlen         = sizeof(int),
 546                 .mode           = 0644,
 547                 .proc_handler   = &proc_dointvec,
 548         },
 549         {
 550                 .ctl_name       = KERN_RANDOM,
 551                 .procname       = "random",
 552                 .mode           = 0555,
 553                 .child          = random_table,
 554         },
 555         {
 556                 .ctl_name       = KERN_OVERFLOWUID,
 557                 .procname       = "overflowuid",
 558                 .data           = &overflowuid,
 559                 .maxlen         = sizeof(int),
 560                 .mode           = 0644,
 561                 .proc_handler   = &proc_dointvec_minmax,
 562                 .strategy       = &sysctl_intvec,
 563                 .extra1         = &minolduid,
 564                 .extra2         = &maxolduid,
 565         },
 566         {
 567                 .ctl_name       = KERN_OVERFLOWGID,
 568                 .procname       = "overflowgid",
 569                 .data           = &overflowgid,
 570                 .maxlen         = sizeof(int),
 571                 .mode           = 0644,
 572                 .proc_handler   = &proc_dointvec_minmax,
 573                 .strategy       = &sysctl_intvec,
 574                 .extra1         = &minolduid,
 575                 .extra2         = &maxolduid,
 576         },
 577 #ifdef CONFIG_S390
 578 #ifdef CONFIG_MATHEMU
 579         {
 580                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 581                 .procname       = "ieee_emulation_warnings",
 582                 .data           = &sysctl_ieee_emulation_warnings,
 583                 .maxlen         = sizeof(int),
 584                 .mode           = 0644,
 585                 .proc_handler   = &proc_dointvec,
 586         },
 587 #endif
 588         {
 589                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 590                 .procname       = "userprocess_debug",
 591                 .data           = &sysctl_userprocess_debug,
 592                 .maxlen         = sizeof(int),
 593                 .mode           = 0644,
 594                 .proc_handler   = &proc_dointvec,
 595         },
 596 #endif
 597         {
 598                 .ctl_name       = KERN_PIDMAX,
 599                 .procname       = "pid_max",
 600                 .data           = &pid_max,
 601                 .maxlen         = sizeof (int),
 602                 .mode           = 0644,
 603                 .proc_handler   = &proc_dointvec_minmax,
 604                 .strategy       = sysctl_intvec,
 605                 .extra1         = &pid_max_min,
 606                 .extra2         = &pid_max_max,
 607         },
 608         {
 609                 .ctl_name       = KERN_PANIC_ON_OOPS,
 610                 .procname       = "panic_on_oops",
 611                 .data           = &panic_on_oops,
 612                 .maxlen         = sizeof(int),
 613                 .mode           = 0644,
 614                 .proc_handler   = &proc_dointvec,
 615         },
 616 #if defined CONFIG_PRINTK
 617         {
 618                 .ctl_name       = KERN_PRINTK,
 619                 .procname       = "printk",
 620                 .data           = &console_loglevel,
 621                 .maxlen         = 4*sizeof(int),
 622                 .mode           = 0644,
 623                 .proc_handler   = &proc_dointvec,
 624         },
 625         {
 626                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 627                 .procname       = "printk_ratelimit",
 628                 .data           = &printk_ratelimit_state.interval,
 629                 .maxlen         = sizeof(int),
 630                 .mode           = 0644,
 631                 .proc_handler   = &proc_dointvec_jiffies,
 632                 .strategy       = &sysctl_jiffies,
 633         },
 634         {
 635                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 636                 .procname       = "printk_ratelimit_burst",
 637                 .data           = &printk_ratelimit_state.burst,
 638                 .maxlen         = sizeof(int),
 639                 .mode           = 0644,
 640                 .proc_handler   = &proc_dointvec,
 641         },
 642 #endif
 643         {
 644                 .ctl_name       = KERN_NGROUPS_MAX,
 645                 .procname       = "ngroups_max",
 646                 .data           = &ngroups_max,
 647                 .maxlen         = sizeof (int),
 648                 .mode           = 0444,
 649                 .proc_handler   = &proc_dointvec,
 650         },
 651 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 652         {
 653                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 654                 .procname       = "unknown_nmi_panic",
 655                 .data           = &unknown_nmi_panic,
 656                 .maxlen         = sizeof (int),
 657                 .mode           = 0644,
 658                 .proc_handler   = &proc_dointvec,
 659         },
 660         {
 661                 .procname       = "nmi_watchdog",
 662                 .data           = &nmi_watchdog_enabled,
 663                 .maxlen         = sizeof (int),
 664                 .mode           = 0644,
 665                 .proc_handler   = &proc_nmi_enabled,
 666         },
 667 #endif
 668 #if defined(CONFIG_X86)
 669         {
 670                 .ctl_name       = KERN_PANIC_ON_NMI,
 671                 .procname       = "panic_on_unrecovered_nmi",
 672                 .data           = &panic_on_unrecovered_nmi,
 673                 .maxlen         = sizeof(int),
 674                 .mode           = 0644,
 675                 .proc_handler   = &proc_dointvec,
 676         },
 677         {
 678                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 679                 .procname       = "bootloader_type",
 680                 .data           = &bootloader_type,
 681                 .maxlen         = sizeof (int),
 682                 .mode           = 0444,
 683                 .proc_handler   = &proc_dointvec,
 684         },
 685         {
 686                 .ctl_name       = CTL_UNNUMBERED,
 687                 .procname       = "kstack_depth_to_print",
 688                 .data           = &kstack_depth_to_print,
 689                 .maxlen         = sizeof(int),
 690                 .mode           = 0644,
 691                 .proc_handler   = &proc_dointvec,
 692         },
 693         {
 694                 .ctl_name       = CTL_UNNUMBERED,
 695                 .procname       = "io_delay_type",
 696                 .data           = &io_delay_type,
 697                 .maxlen         = sizeof(int),
 698                 .mode           = 0644,
 699                 .proc_handler   = &proc_dointvec,
 700         },
 701 #endif
 702 #if defined(CONFIG_MMU)
 703         {
 704                 .ctl_name       = KERN_RANDOMIZE,
 705                 .procname       = "randomize_va_space",
 706                 .data           = &randomize_va_space,
 707                 .maxlen         = sizeof(int),
 708                 .mode           = 0644,
 709                 .proc_handler   = &proc_dointvec,
 710         },
 711 #endif
 712 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 713         {
 714                 .ctl_name       = KERN_SPIN_RETRY,
 715                 .procname       = "spin_retry",
 716                 .data           = &spin_retry,
 717                 .maxlen         = sizeof (int),
 718                 .mode           = 0644,
 719                 .proc_handler   = &proc_dointvec,
 720         },
 721 #endif
 722 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 723         {
 724                 .procname       = "acpi_video_flags",
 725                 .data           = &acpi_realmode_flags,
 726                 .maxlen         = sizeof (unsigned long),
 727                 .mode           = 0644,
 728                 .proc_handler   = &proc_doulongvec_minmax,
 729         },
 730 #endif
 731 #ifdef CONFIG_IA64
 732         {
 733                 .ctl_name       = KERN_IA64_UNALIGNED,
 734                 .procname       = "ignore-unaligned-usertrap",
 735                 .data           = &no_unaligned_warning,
 736                 .maxlen         = sizeof (int),
 737                 .mode           = 0644,
 738                 .proc_handler   = &proc_dointvec,
 739         },
 740 #endif
 741 #ifdef CONFIG_DETECT_SOFTLOCKUP
 742         {
 743                 .ctl_name       = CTL_UNNUMBERED,
 744                 .procname       = "softlockup_panic",
 745                 .data           = &softlockup_panic,
 746                 .maxlen         = sizeof(int),
 747                 .mode           = 0644,
 748                 .proc_handler   = &proc_dointvec_minmax,
 749                 .strategy       = &sysctl_intvec,
 750                 .extra1         = &zero,
 751                 .extra2         = &one,
 752         },
 753         {
 754                 .ctl_name       = CTL_UNNUMBERED,
 755                 .procname       = "softlockup_thresh",
 756                 .data           = &softlockup_thresh,
 757                 .maxlen         = sizeof(int),
 758                 .mode           = 0644,
 759                 .proc_handler   = &proc_dointvec_minmax,
 760                 .strategy       = &sysctl_intvec,
 761                 .extra1         = &neg_one,
 762                 .extra2         = &sixty,
 763         },
 764         {
 765                 .ctl_name       = CTL_UNNUMBERED,
 766                 .procname       = "hung_task_check_count",
 767                 .data           = &sysctl_hung_task_check_count,
 768                 .maxlen         = sizeof(unsigned long),
 769                 .mode           = 0644,
 770                 .proc_handler   = &proc_doulongvec_minmax,
 771                 .strategy       = &sysctl_intvec,
 772         },
 773         {
 774                 .ctl_name       = CTL_UNNUMBERED,
 775                 .procname       = "hung_task_timeout_secs",
 776                 .data           = &sysctl_hung_task_timeout_secs,
 777                 .maxlen         = sizeof(unsigned long),
 778                 .mode           = 0644,
 779                 .proc_handler   = &proc_doulongvec_minmax,
 780                 .strategy       = &sysctl_intvec,
 781         },
 782         {
 783                 .ctl_name       = CTL_UNNUMBERED,
 784                 .procname       = "hung_task_warnings",
 785                 .data           = &sysctl_hung_task_warnings,
 786                 .maxlen         = sizeof(unsigned long),
 787                 .mode           = 0644,
 788                 .proc_handler   = &proc_doulongvec_minmax,
 789                 .strategy       = &sysctl_intvec,
 790         },
 791 #endif
 792 #ifdef CONFIG_COMPAT
 793         {
 794                 .ctl_name       = KERN_COMPAT_LOG,
 795                 .procname       = "compat-log",
 796                 .data           = &compat_log,
 797                 .maxlen         = sizeof (int),
 798                 .mode           = 0644,
 799                 .proc_handler   = &proc_dointvec,
 800         },
 801 #endif
 802 #ifdef CONFIG_RT_MUTEXES
 803         {
 804                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 805                 .procname       = "max_lock_depth",
 806                 .data           = &max_lock_depth,
 807                 .maxlen         = sizeof(int),
 808                 .mode           = 0644,
 809                 .proc_handler   = &proc_dointvec,
 810         },
 811 #endif
 812 #ifdef CONFIG_PROC_FS
 813         {
 814                 .ctl_name       = CTL_UNNUMBERED,
 815                 .procname       = "maps_protect",
 816                 .data           = &maps_protect,
 817                 .maxlen         = sizeof(int),
 818                 .mode           = 0644,
 819                 .proc_handler   = &proc_dointvec,
 820         },
 821 #endif
 822         {
 823                 .ctl_name       = CTL_UNNUMBERED,
 824                 .procname       = "poweroff_cmd",
 825                 .data           = &poweroff_cmd,
 826                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 827                 .mode           = 0644,
 828                 .proc_handler   = &proc_dostring,
 829                 .strategy       = &sysctl_string,
 830         },
 831 #ifdef CONFIG_KEYS
 832         {
 833                 .ctl_name       = CTL_UNNUMBERED,
 834                 .procname       = "keys",
 835                 .mode           = 0555,
 836                 .child          = key_sysctls,
 837         },
 838 #endif
 839 #ifdef CONFIG_RCU_TORTURE_TEST
 840         {
 841                 .ctl_name       = CTL_UNNUMBERED,
 842                 .procname       = "rcutorture_runnable",
 843                 .data           = &rcutorture_runnable,
 844                 .maxlen         = sizeof(int),
 845                 .mode           = 0644,
 846                 .proc_handler   = &proc_dointvec,
 847         },
 848 #endif
 849 /*
 850  * NOTE: do not add new entries to this table unless you have read
 851  * Documentation/sysctl/ctl_unnumbered.txt
 852  */
 853         { .ctl_name = 0 }
 854 };
 855
 856 static struct ctl_table vm_table[] = {
 857         {
 858                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 859                 .procname       = "overcommit_memory",
 860                 .data           = &sysctl_overcommit_memory,
 861                 .maxlen         = sizeof(sysctl_overcommit_memory),
 862                 .mode           = 0644,
 863                 .proc_handler   = &proc_dointvec,
 864         },
 865         {
 866                 .ctl_name       = VM_PANIC_ON_OOM,
 867                 .procname       = "panic_on_oom",
 868                 .data           = &sysctl_panic_on_oom,
 869                 .maxlen         = sizeof(sysctl_panic_on_oom),
 870                 .mode           = 0644,
 871                 .proc_handler   = &proc_dointvec,
 872         },
 873         {
 874                 .ctl_name       = CTL_UNNUMBERED,
 875                 .procname       = "oom_kill_allocating_task",
 876                 .data           = &sysctl_oom_kill_allocating_task,
 877                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
 878                 .mode           = 0644,
 879                 .proc_handler   = &proc_dointvec,
 880         },
 881         {
 882                 .ctl_name       = CTL_UNNUMBERED,
 883                 .procname       = "oom_dump_tasks",
 884                 .data           = &sysctl_oom_dump_tasks,
 885                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
 886                 .mode           = 0644,
 887                 .proc_handler   = &proc_dointvec,
 888         },
 889         {
 890                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 891                 .procname       = "overcommit_ratio",
 892                 .data           = &sysctl_overcommit_ratio,
 893                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 894                 .mode           = 0644,
 895                 .proc_handler   = &proc_dointvec,
 896         },
 897         {
 898                 .ctl_name       = VM_PAGE_CLUSTER,
 899                 .procname       = "page-cluster",
 900                 .data           = &page_cluster,
 901                 .maxlen         = sizeof(int),
 902                 .mode           = 0644,
 903                 .proc_handler   = &proc_dointvec,
 904         },
 905         {
 906                 .ctl_name       = VM_DIRTY_BACKGROUND,
 907                 .procname       = "dirty_background_ratio",
 908                 .data           = &dirty_background_ratio,
 909                 .maxlen         = sizeof(dirty_background_ratio),
 910                 .mode           = 0644,
 911                 .proc_handler   = &proc_dointvec_minmax,
 912                 .strategy       = &sysctl_intvec,
 913                 .extra1         = &zero,
 914                 .extra2         = &one_hundred,
 915         },
 916         {
 917                 .ctl_name       = VM_DIRTY_RATIO,
 918                 .procname       = "dirty_ratio",
 919                 .data           = &vm_dirty_ratio,
 920                 .maxlen         = sizeof(vm_dirty_ratio),
 921                 .mode           = 0644,
 922                 .proc_handler   = &dirty_ratio_handler,
 923                 .strategy       = &sysctl_intvec,
 924                 .extra1         = &zero,
 925                 .extra2         = &one_hundred,
 926         },
 927         {
 928                 .procname       = "dirty_writeback_centisecs",
 929                 .data           = &dirty_writeback_interval,
 930                 .maxlen         = sizeof(dirty_writeback_interval),
 931                 .mode           = 0644,
 932                 .proc_handler   = &dirty_writeback_centisecs_handler,
 933         },
 934         {
 935                 .procname       = "dirty_expire_centisecs",
 936                 .data           = &dirty_expire_interval,
 937                 .maxlen         = sizeof(dirty_expire_interval),
 938                 .mode           = 0644,
 939                 .proc_handler   = &proc_dointvec_userhz_jiffies,
 940         },
 941         {
 942                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 943                 .procname       = "nr_pdflush_threads",
 944                 .data           = &nr_pdflush_threads,
 945                 .maxlen         = sizeof nr_pdflush_threads,
 946                 .mode           = 0444 /* read-only*/,
 947                 .proc_handler   = &proc_dointvec,
 948         },
 949         {
 950                 .ctl_name       = VM_SWAPPINESS,
 951                 .procname       = "swappiness",
 952                 .data           = &vm_swappiness,
 953                 .maxlen         = sizeof(vm_swappiness),
 954                 .mode           = 0644,
 955                 .proc_handler   = &proc_dointvec_minmax,
 956                 .strategy       = &sysctl_intvec,
 957                 .extra1         = &zero,
 958                 .extra2         = &one_hundred,
 959         },
 960 #ifdef CONFIG_HUGETLB_PAGE
 961          {
 962                 .procname       = "nr_hugepages",
 963                 .data           = NULL,
 964                 .maxlen         = sizeof(unsigned long),
 965                 .mode           = 0644,
 966                 .proc_handler   = &hugetlb_sysctl_handler,
 967                 .extra1         = (void *)&hugetlb_zero,
 968                 .extra2         = (void *)&hugetlb_infinity,
 969          },
 970          {
 971                 .ctl_name       = VM_HUGETLB_GROUP,
 972                 .procname       = "hugetlb_shm_group",
 973                 .data           = &sysctl_hugetlb_shm_group,
 974                 .maxlen         = sizeof(gid_t),
 975                 .mode           = 0644,
 976                 .proc_handler   = &proc_dointvec,
 977          },
 978          {
 979                 .ctl_name       = CTL_UNNUMBERED,
 980                 .procname       = "hugepages_treat_as_movable",
 981                 .data           = &hugepages_treat_as_movable,
 982                 .maxlen         = sizeof(int),
 983                 .mode           = 0644,
 984                 .proc_handler   = &hugetlb_treat_movable_handler,
 985         },
 986         {
 987                 .ctl_name       = CTL_UNNUMBERED,
 988                 .procname       = "nr_overcommit_hugepages",
 989                 .data           = NULL,
 990                 .maxlen         = sizeof(unsigned long),
 991                 .mode           = 0644,
 992                 .proc_handler   = &hugetlb_overcommit_handler,
 993                 .extra1         = (void *)&hugetlb_zero,
 994                 .extra2         = (void *)&hugetlb_infinity,
 995         },
 996 #endif
 997         {
 998                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 999                 .procname       = "lowmem_reserve_ratio",
1000                 .data           = &sysctl_lowmem_reserve_ratio,
1001                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1002                 .mode           = 0644,
1003                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
1004                 .strategy       = &sysctl_intvec,
1005         },
1006         {
1007                 .ctl_name       = VM_DROP_PAGECACHE,
1008                 .procname       = "drop_caches",
1009                 .data           = &sysctl_drop_caches,
1010                 .maxlen         = sizeof(int),
1011                 .mode           = 0644,
1012                 .proc_handler   = drop_caches_sysctl_handler,
1013                 .strategy       = &sysctl_intvec,
1014         },
1015         {
1016                 .ctl_name       = VM_MIN_FREE_KBYTES,
1017                 .procname       = "min_free_kbytes",
1018                 .data           = &min_free_kbytes,
1019                 .maxlen         = sizeof(min_free_kbytes),
1020                 .mode           = 0644,
1021                 .proc_handler   = &min_free_kbytes_sysctl_handler,
1022                 .strategy       = &sysctl_intvec,
1023                 .extra1         = &zero,
1024         },
1025         {
1026                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
1027                 .procname       = "percpu_pagelist_fraction",
1028                 .data           = &percpu_pagelist_fraction,
1029                 .maxlen         = sizeof(percpu_pagelist_fraction),
1030                 .mode           = 0644,
1031                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
1032                 .strategy       = &sysctl_intvec,
1033                 .extra1         = &min_percpu_pagelist_fract,
1034         },
1035 #ifdef CONFIG_MMU
1036         {
1037                 .ctl_name       = VM_MAX_MAP_COUNT,
1038                 .procname       = "max_map_count",
1039                 .data           = &sysctl_max_map_count,
1040                 .maxlen         = sizeof(sysctl_max_map_count),
1041                 .mode           = 0644,
1042                 .proc_handler   = &proc_dointvec
1043         },
1044 #endif
1045         {
1046                 .ctl_name       = VM_LAPTOP_MODE,
1047                 .procname       = "laptop_mode",
1048                 .data           = &laptop_mode,
1049                 .maxlen         = sizeof(laptop_mode),
1050                 .mode           = 0644,
1051                 .proc_handler   = &proc_dointvec_jiffies,
1052                 .strategy       = &sysctl_jiffies,
1053         },
1054         {
1055                 .ctl_name       = VM_BLOCK_DUMP,
1056                 .procname       = "block_dump",
1057                 .data           = &block_dump,
1058                 .maxlen         = sizeof(block_dump),
1059                 .mode           = 0644,
1060                 .proc_handler   = &proc_dointvec,
1061                 .strategy       = &sysctl_intvec,
1062                 .extra1         = &zero,
1063         },
1064         {
1065                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
1066                 .procname       = "vfs_cache_pressure",
1067                 .data           = &sysctl_vfs_cache_pressure,
1068                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1069                 .mode           = 0644,
1070                 .proc_handler   = &proc_dointvec,
1071                 .strategy       = &sysctl_intvec,
1072                 .extra1         = &zero,
1073         },
1074 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1075         {
1076                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
1077                 .procname       = "legacy_va_layout",
1078                 .data           = &sysctl_legacy_va_layout,
1079                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1080                 .mode           = 0644,
1081                 .proc_handler   = &proc_dointvec,
1082                 .strategy       = &sysctl_intvec,
1083                 .extra1         = &zero,
1084         },
1085 #endif
1086 #ifdef CONFIG_NUMA
1087         {
1088                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
1089                 .procname       = "zone_reclaim_mode",
1090                 .data           = &zone_reclaim_mode,
1091                 .maxlen         = sizeof(zone_reclaim_mode),
1092                 .mode           = 0644,
1093                 .proc_handler   = &proc_dointvec,
1094                 .strategy       = &sysctl_intvec,
1095                 .extra1         = &zero,
1096         },
1097         {
1098                 .ctl_name       = VM_MIN_UNMAPPED,
1099                 .procname       = "min_unmapped_ratio",
1100                 .data           = &sysctl_min_unmapped_ratio,
1101                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1102                 .mode           = 0644,
1103                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1104                 .strategy       = &sysctl_intvec,
1105                 .extra1         = &zero,
1106                 .extra2         = &one_hundred,
1107         },
1108         {
1109                 .ctl_name       = VM_MIN_SLAB,
1110                 .procname       = "min_slab_ratio",
1111                 .data           = &sysctl_min_slab_ratio,
1112                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1113                 .mode           = 0644,
1114                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1115                 .strategy       = &sysctl_intvec,
1116                 .extra1         = &zero,
1117                 .extra2         = &one_hundred,
1118         },
1119 #endif
1120 #ifdef CONFIG_SMP
1121         {
1122                 .ctl_name       = CTL_UNNUMBERED,
1123                 .procname       = "stat_interval",
1124                 .data           = &sysctl_stat_interval,
1125                 .maxlen         = sizeof(sysctl_stat_interval),
1126                 .mode           = 0644,
1127                 .proc_handler   = &proc_dointvec_jiffies,
1128                 .strategy       = &sysctl_jiffies,
1129         },
1130 #endif
1131 #ifdef CONFIG_SECURITY
1132         {
1133                 .ctl_name       = CTL_UNNUMBERED,
1134                 .procname       = "mmap_min_addr",
1135                 .data           = &mmap_min_addr,
1136                 .maxlen         = sizeof(unsigned long),
1137                 .mode           = 0644,
1138                 .proc_handler   = &proc_doulongvec_minmax,
1139         },
1140 #endif
1141 #ifdef CONFIG_NUMA
1142         {
1143                 .ctl_name       = CTL_UNNUMBERED,
1144                 .procname       = "numa_zonelist_order",
1145                 .data           = &numa_zonelist_order,
1146                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1147                 .mode           = 0644,
1148                 .proc_handler   = &numa_zonelist_order_handler,
1149                 .strategy       = &sysctl_string,
1150         },
1151 #endif
1152 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1153    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1154         {
1155                 .ctl_name       = VM_VDSO_ENABLED,
1156                 .procname       = "vdso_enabled",
1157                 .data           = &vdso_enabled,
1158                 .maxlen         = sizeof(vdso_enabled),
1159                 .mode           = 0644,
1160                 .proc_handler   = &proc_dointvec,
1161                 .strategy       = &sysctl_intvec,
1162                 .extra1         = &zero,
1163         },
1164 #endif
1165 #ifdef CONFIG_HIGHMEM
1166         {
1167                 .ctl_name       = CTL_UNNUMBERED,
1168                 .procname       = "highmem_is_dirtyable",
1169                 .data           = &vm_highmem_is_dirtyable,
1170                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1171                 .mode           = 0644,
1172                 .proc_handler   = &proc_dointvec_minmax,
1173                 .strategy       = &sysctl_intvec,
1174                 .extra1         = &zero,
1175                 .extra2         = &one,
1176         },
1177 #endif
1178 /*
1179  * NOTE: do not add new entries to this table unless you have read
1180  * Documentation/sysctl/ctl_unnumbered.txt
1181  */
1182         { .ctl_name = 0 }
1183 };
1184
1185 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1186 static struct ctl_table binfmt_misc_table[] = {
1187         { .ctl_name = 0 }
1188 };
1189 #endif
1190
1191 static struct ctl_table fs_table[] = {
1192         {
1193                 .ctl_name       = FS_NRINODE,
1194                 .procname       = "inode-nr",
1195                 .data           = &inodes_stat,
1196                 .maxlen         = 2*sizeof(int),
1197                 .mode           = 0444,
1198                 .proc_handler   = &proc_dointvec,
1199         },
1200         {
1201                 .ctl_name       = FS_STATINODE,
1202                 .procname       = "inode-state",
1203                 .data           = &inodes_stat,
1204                 .maxlen         = 7*sizeof(int),
1205                 .mode           = 0444,
1206                 .proc_handler   = &proc_dointvec,
1207         },
1208         {
1209                 .procname       = "file-nr",
1210                 .data           = &files_stat,
1211                 .maxlen         = 3*sizeof(int),
1212                 .mode           = 0444,
1213                 .proc_handler   = &proc_nr_files,
1214         },
1215         {
1216                 .ctl_name       = FS_MAXFILE,
1217                 .procname       = "file-max",
1218                 .data           = &files_stat.max_files,
1219                 .maxlen         = sizeof(int),
1220                 .mode           = 0644,
1221                 .proc_handler   = &proc_dointvec,
1222         },
1223         {
1224                 .ctl_name       = CTL_UNNUMBERED,
1225                 .procname       = "nr_open",
1226                 .data           = &sysctl_nr_open,
1227                 .maxlen         = sizeof(int),
1228                 .mode           = 0644,
1229                 .proc_handler   = &proc_dointvec_minmax,
1230                 .extra1         = &sysctl_nr_open_min,
1231                 .extra2         = &sysctl_nr_open_max,
1232         },
1233         {
1234                 .ctl_name       = FS_DENTRY,
1235                 .procname       = "dentry-state",
1236                 .data           = &dentry_stat,
1237                 .maxlen         = 6*sizeof(int),
1238                 .mode           = 0444,
1239                 .proc_handler   = &proc_dointvec,
1240         },
1241         {
1242                 .ctl_name       = FS_OVERFLOWUID,
1243                 .procname       = "overflowuid",
1244                 .data           = &fs_overflowuid,
1245                 .maxlen         = sizeof(int),
1246                 .mode           = 0644,
1247                 .proc_handler   = &proc_dointvec_minmax,
1248                 .strategy       = &sysctl_intvec,
1249                 .extra1         = &minolduid,
1250                 .extra2         = &maxolduid,
1251         },
1252         {
1253                 .ctl_name       = FS_OVERFLOWGID,
1254                 .procname       = "overflowgid",
1255                 .data           = &fs_overflowgid,
1256                 .maxlen         = sizeof(int),
1257                 .mode           = 0644,
1258                 .proc_handler   = &proc_dointvec_minmax,
1259                 .strategy       = &sysctl_intvec,
1260                 .extra1         = &minolduid,
1261                 .extra2         = &maxolduid,
1262         },
1263         {
1264                 .ctl_name       = FS_LEASES,
1265                 .procname       = "leases-enable",
1266                 .data           = &leases_enable,
1267                 .maxlen         = sizeof(int),
1268                 .mode           = 0644,
1269                 .proc_handler   = &proc_dointvec,
1270         },
1271 #ifdef CONFIG_DNOTIFY
1272         {
1273                 .ctl_name       = FS_DIR_NOTIFY,
1274                 .procname       = "dir-notify-enable",
1275                 .data           = &dir_notify_enable,
1276                 .maxlen         = sizeof(int),
1277                 .mode           = 0644,
1278                 .proc_handler   = &proc_dointvec,
1279         },
1280 #endif
1281 #ifdef CONFIG_MMU
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         {
1294                 .procname       = "aio-nr",
1295                 .data           = &aio_nr,
1296                 .maxlen         = sizeof(aio_nr),
1297                 .mode           = 0444,
1298                 .proc_handler   = &proc_doulongvec_minmax,
1299         },
1300         {
1301                 .procname       = "aio-max-nr",
1302                 .data           = &aio_max_nr,
1303                 .maxlen         = sizeof(aio_max_nr),
1304                 .mode           = 0644,
1305                 .proc_handler   = &proc_doulongvec_minmax,
1306         },
1307 #ifdef CONFIG_INOTIFY_USER
1308         {
1309                 .ctl_name       = FS_INOTIFY,
1310                 .procname       = "inotify",
1311                 .mode           = 0555,
1312                 .child          = inotify_table,
1313         },
1314 #endif
1315 #endif
1316         {
1317                 .ctl_name       = KERN_SETUID_DUMPABLE,
1318                 .procname       = "suid_dumpable",
1319                 .data           = &suid_dumpable,
1320                 .maxlen         = sizeof(int),
1321                 .mode           = 0644,
1322                 .proc_handler   = &proc_dointvec,
1323         },
1324 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1325         {
1326                 .ctl_name       = CTL_UNNUMBERED,
1327                 .procname       = "binfmt_misc",
1328                 .mode           = 0555,
1329                 .child          = binfmt_misc_table,
1330         },
1331 #endif
1332 /*
1333  * NOTE: do not add new entries to this table unless you have read
1334  * Documentation/sysctl/ctl_unnumbered.txt
1335  */
1336         { .ctl_name = 0 }
1337 };
1338
1339 static struct ctl_table debug_table[] = {
1340 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1341         {
1342                 .ctl_name       = CTL_UNNUMBERED,
1343                 .procname       = "exception-trace",
1344                 .data           = &show_unhandled_signals,
1345                 .maxlen         = sizeof(int),
1346                 .mode           = 0644,
1347                 .proc_handler   = proc_dointvec
1348         },
1349 #endif
1350         { .ctl_name = 0 }
1351 };
1352
1353 static struct ctl_table dev_table[] = {
1354         { .ctl_name = 0 }
1355 };
1356
1357 static DEFINE_SPINLOCK(sysctl_lock);
1358
1359 /* called under sysctl_lock */
1360 static int use_table(struct ctl_table_header *p)
1361 {
1362         if (unlikely(p->unregistering))
1363                 return 0;
1364         p->used++;
1365         return 1;
1366 }
1367
1368 /* called under sysctl_lock */
1369 static void unuse_table(struct ctl_table_header *p)
1370 {
1371         if (!--p->used)
1372                 if (unlikely(p->unregistering))
1373                         complete(p->unregistering);
1374 }
1375
1376 /* called under sysctl_lock, will reacquire if has to wait */
1377 static void start_unregistering(struct ctl_table_header *p)
1378 {
1379         /*
1380          * if p->used is 0, nobody will ever touch that entry again;
1381          * we'll eliminate all paths to it before dropping sysctl_lock
1382          */
1383         if (unlikely(p->used)) {
1384                 struct completion wait;
1385                 init_completion(&wait);
1386                 p->unregistering = &wait;
1387                 spin_unlock(&sysctl_lock);
1388                 wait_for_completion(&wait);
1389                 spin_lock(&sysctl_lock);
1390         } else {
1391                 /* anything non-NULL; we'll never dereference it */
1392                 p->unregistering = ERR_PTR(-EINVAL);
1393         }
1394         /*
1395          * do not remove from the list until nobody holds it; walking the
1396          * list in do_sysctl() relies on that.
1397          */
1398         list_del_init(&p->ctl_entry);
1399 }
1400
1401 void sysctl_head_get(struct ctl_table_header *head)
1402 {
1403         spin_lock(&sysctl_lock);
1404         head->count++;
1405         spin_unlock(&sysctl_lock);
1406 }
1407
1408 void sysctl_head_put(struct ctl_table_header *head)
1409 {
1410         spin_lock(&sysctl_lock);
1411         if (!--head->count)
1412                 kfree(head);
1413         spin_unlock(&sysctl_lock);
1414 }
1415
1416 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1417 {
1418         if (!head)
1419                 BUG();
1420         spin_lock(&sysctl_lock);
1421         if (!use_table(head))
1422                 head = ERR_PTR(-ENOENT);
1423         spin_unlock(&sysctl_lock);
1424         return head;
1425 }
1426
1427 void sysctl_head_finish(struct ctl_table_header *head)
1428 {
1429         if (!head)
1430                 return;
1431         spin_lock(&sysctl_lock);
1432         unuse_table(head);
1433         spin_unlock(&sysctl_lock);
1434 }
1435
1436 static struct ctl_table_set *
1437 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1438 {
1439         struct ctl_table_set *set = &root->default_set;
1440         if (root->lookup)
1441                 set = root->lookup(root, namespaces);
1442         return set;
1443 }
1444
1445 static struct list_head *
1446 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1447 {
1448         struct ctl_table_set *set = lookup_header_set(root, namespaces);
1449         return &set->list;
1450 }
1451
1452 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1453                                             struct ctl_table_header *prev)
1454 {
1455         struct ctl_table_root *root;
1456         struct list_head *header_list;
1457         struct ctl_table_header *head;
1458         struct list_head *tmp;
1459
1460         spin_lock(&sysctl_lock);
1461         if (prev) {
1462                 head = prev;
1463                 tmp = &prev->ctl_entry;
1464                 unuse_table(prev);
1465                 goto next;
1466         }
1467         tmp = &root_table_header.ctl_entry;
1468         for (;;) {
1469                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1470
1471                 if (!use_table(head))
1472                         goto next;
1473                 spin_unlock(&sysctl_lock);
1474                 return head;
1475         next:
1476                 root = head->root;
1477                 tmp = tmp->next;
1478                 header_list = lookup_header_list(root, namespaces);
1479                 if (tmp != header_list)
1480                         continue;
1481
1482                 do {
1483                         root = list_entry(root->root_list.next,
1484                                         struct ctl_table_root, root_list);
1485                         if (root == &sysctl_table_root)
1486                                 goto out;
1487                         header_list = lookup_header_list(root, namespaces);
1488                 } while (list_empty(header_list));
1489                 tmp = header_list->next;
1490         }
1491 out:
1492         spin_unlock(&sysctl_lock);
1493         return NULL;
1494 }
1495
1496 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1497 {
1498         return __sysctl_head_next(current->nsproxy, prev);
1499 }
1500
1501 void register_sysctl_root(struct ctl_table_root *root)
1502 {
1503         spin_lock(&sysctl_lock);
1504         list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1505         spin_unlock(&sysctl_lock);
1506 }
1507
1508 #ifdef CONFIG_SYSCTL_SYSCALL
1509 /* Perform the actual read/write of a sysctl table entry. */
1510 static int do_sysctl_strategy(struct ctl_table_root *root,
1511                         struct ctl_table *table,
1512                         int __user *name, int nlen,
1513                         void __user *oldval, size_t __user *oldlenp,
1514                         void __user *newval, size_t newlen)
1515 {
1516         int op = 0, rc;
1517
1518         if (oldval)
1519                 op |= MAY_READ;
1520         if (newval)
1521                 op |= MAY_WRITE;
1522         if (sysctl_perm(root, table, op))
1523                 return -EPERM;
1524
1525         if (table->strategy) {
1526                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1527                                      newval, newlen);
1528                 if (rc < 0)
1529                         return rc;
1530                 if (rc > 0)
1531                         return 0;
1532         }
1533
1534         /* If there is no strategy routine, or if the strategy returns
1535          * zero, proceed with automatic r/w */
1536         if (table->data && table->maxlen) {
1537                 rc = sysctl_data(table, name, nlen, oldval, oldlenp,
1538                                  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, name, nlen,
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 #define OP_SET  0
2240 #define OP_AND  1
2241 #define OP_OR   2
2242
2243 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
2244                                       int *valp,
2245                                       int write, void *data)
2246 {
2247         int op = *(int *)data;
2248         if (write) {
2249                 int val = *negp ? -*lvalp : *lvalp;
2250                 switch(op) {
2251                 case OP_SET:    *valp = val; break;
2252                 case OP_AND:    *valp &= val; break;
2253                 case OP_OR:     *valp |= val; break;
2254                 }
2255         } else {
2256                 int val = *valp;
2257                 if (val < 0) {
2258                         *negp = -1;
2259                         *lvalp = (unsigned long)-val;
2260                 } else {
2261                         *negp = 0;
2262                         *lvalp = (unsigned long)val;
2263                 }
2264         }
2265         return 0;
2266 }
2267
2268 /*
2269  *      Taint values can only be increased
2270  */
2271 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
2272                                void __user *buffer, size_t *lenp, loff_t *ppos)
2273 {
2274         int op;
2275
2276         if (write && !capable(CAP_SYS_ADMIN))
2277                 return -EPERM;
2278
2279         op = OP_OR;
2280         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2281                                 do_proc_dointvec_bset_conv,&op);
2282 }
2283
2284 struct do_proc_dointvec_minmax_conv_param {
2285         int *min;
2286         int *max;
2287 };
2288
2289 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2290                                         int *valp,
2291                                         int write, void *data)
2292 {
2293         struct do_proc_dointvec_minmax_conv_param *param = data;
2294         if (write) {
2295                 int val = *negp ? -*lvalp : *lvalp;
2296                 if ((param->min && *param->min > val) ||
2297                     (param->max && *param->max < val))
2298                         return -EINVAL;
2299                 *valp = val;
2300         } else {
2301                 int val = *valp;
2302                 if (val < 0) {
2303                         *negp = -1;
2304                         *lvalp = (unsigned long)-val;
2305                 } else {
2306                         *negp = 0;
2307                         *lvalp = (unsigned long)val;
2308                 }
2309         }
2310         return 0;
2311 }
2312
2313 /**
2314  * proc_dointvec_minmax - read a vector of integers with min/max values
2315  * @table: the sysctl table
2316  * @write: %TRUE if this is a write to the sysctl file
2317  * @filp: the file structure
2318  * @buffer: the user buffer
2319  * @lenp: the size of the user buffer
2320  * @ppos: file position
2321  *
2322  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2323  * values from/to the user buffer, treated as an ASCII string.
2324  *
2325  * This routine will ensure the values are within the range specified by
2326  * table->extra1 (min) and table->extra2 (max).
2327  *
2328  * Returns 0 on success.
2329  */
2330 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2331                   void __user *buffer, size_t *lenp, loff_t *ppos)
2332 {
2333         struct do_proc_dointvec_minmax_conv_param param = {
2334                 .min = (int *) table->extra1,
2335                 .max = (int *) table->extra2,
2336         };
2337         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2338                                 do_proc_dointvec_minmax_conv, &param);
2339 }
2340
2341 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2342                                      struct file *filp,
2343                                      void __user *buffer,
2344                                      size_t *lenp, loff_t *ppos,
2345                                      unsigned long convmul,
2346                                      unsigned long convdiv)
2347 {
2348 #define TMPBUFLEN 21
2349         unsigned long *i, *min, *max, val;
2350         int vleft, first=1, neg;
2351         size_t len, left;
2352         char buf[TMPBUFLEN], *p;
2353         char __user *s = buffer;
2354
2355         if (!data || !table->maxlen || !*lenp ||
2356             (*ppos && !write)) {
2357                 *lenp = 0;
2358                 return 0;
2359         }
2360
2361         i = (unsigned long *) data;
2362         min = (unsigned long *) table->extra1;
2363         max = (unsigned long *) table->extra2;
2364         vleft = table->maxlen / sizeof(unsigned long);
2365         left = *lenp;
2366
2367         for (; left && vleft--; i++, min++, max++, first=0) {
2368                 if (write) {
2369                         while (left) {
2370                                 char c;
2371                                 if (get_user(c, s))
2372                                         return -EFAULT;
2373                                 if (!isspace(c))
2374                                         break;
2375                                 left--;
2376                                 s++;
2377                         }
2378                         if (!left)
2379                                 break;
2380                         neg = 0;
2381                         len = left;
2382                         if (len > TMPBUFLEN-1)
2383                                 len = TMPBUFLEN-1;
2384                         if (copy_from_user(buf, s, len))
2385                                 return -EFAULT;
2386                         buf[len] = 0;
2387                         p = buf;
2388                         if (*p == '-' && left > 1) {
2389                                 neg = 1;
2390                                 p++;
2391                         }
2392                         if (*p < '0' || *p > '9')
2393                                 break;
2394                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2395                         len = p-buf;
2396                         if ((len < left) && *p && !isspace(*p))
2397                                 break;
2398                         if (neg)
2399                                 val = -val;
2400                         s += len;
2401                         left -= len;
2402
2403                         if(neg)
2404                                 continue;
2405                         if ((min && val < *min) || (max && val > *max))
2406                                 continue;
2407                         *i = val;
2408                 } else {
2409                         p = buf;
2410                         if (!first)
2411                                 *p++ = '\t';
2412                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2413                         len = strlen(buf);
2414                         if (len > left)
2415                                 len = left;
2416                         if(copy_to_user(s, buf, len))
2417                                 return -EFAULT;
2418                         left -= len;
2419                         s += len;
2420                 }
2421         }
2422
2423         if (!write && !first && left) {
2424                 if(put_user('\n', s))
2425                         return -EFAULT;
2426                 left--, s++;
2427         }
2428         if (write) {
2429                 while (left) {
2430                         char c;
2431                         if (get_user(c, s++))
2432                                 return -EFAULT;
2433                         if (!isspace(c))
2434                                 break;
2435                         left--;
2436                 }
2437         }
2438         if (write && first)
2439                 return -EINVAL;
2440         *lenp -= left;
2441         *ppos += *lenp;
2442         return 0;
2443 #undef TMPBUFLEN
2444 }
2445
2446 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2447                                      struct file *filp,
2448                                      void __user *buffer,
2449                                      size_t *lenp, loff_t *ppos,
2450                                      unsigned long convmul,
2451                                      unsigned long convdiv)
2452 {
2453         return __do_proc_doulongvec_minmax(table->data, table, write,
2454                         filp, buffer, lenp, ppos, convmul, convdiv);
2455 }
2456
2457 /**
2458  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2459  * @table: the sysctl table
2460  * @write: %TRUE if this is a write to the sysctl file
2461  * @filp: the file structure
2462  * @buffer: the user buffer
2463  * @lenp: the size of the user buffer
2464  * @ppos: file position
2465  *
2466  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2467  * values from/to the user buffer, treated as an ASCII string.
2468  *
2469  * This routine will ensure the values are within the range specified by
2470  * table->extra1 (min) and table->extra2 (max).
2471  *
2472  * Returns 0 on success.
2473  */
2474 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2475                            void __user *buffer, size_t *lenp, loff_t *ppos)
2476 {
2477     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2478 }
2479
2480 /**
2481  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2482  * @table: the sysctl table
2483  * @write: %TRUE if this is a write to the sysctl file
2484  * @filp: the file structure
2485  * @buffer: the user buffer
2486  * @lenp: the size of the user buffer
2487  * @ppos: file position
2488  *
2489  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2490  * values from/to the user buffer, treated as an ASCII string. The values
2491  * are treated as milliseconds, and converted to jiffies when they are stored.
2492  *
2493  * This routine will ensure the values are within the range specified by
2494  * table->extra1 (min) and table->extra2 (max).
2495  *
2496  * Returns 0 on success.
2497  */
2498 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2499                                       struct file *filp,
2500                                       void __user *buffer,
2501                                       size_t *lenp, loff_t *ppos)
2502 {
2503     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2504                                      lenp, ppos, HZ, 1000l);
2505 }
2506
2507
2508 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2509                                          int *valp,
2510                                          int write, void *data)
2511 {
2512         if (write) {
2513                 if (*lvalp > LONG_MAX / HZ)
2514                         return 1;
2515                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2516         } else {
2517                 int val = *valp;
2518                 unsigned long lval;
2519                 if (val < 0) {
2520                         *negp = -1;
2521                         lval = (unsigned long)-val;
2522                 } else {
2523                         *negp = 0;
2524                         lval = (unsigned long)val;
2525                 }
2526                 *lvalp = lval / HZ;
2527         }
2528         return 0;
2529 }
2530
2531 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2532                                                 int *valp,
2533                                                 int write, void *data)
2534 {
2535         if (write) {
2536                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2537                         return 1;
2538                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2539         } else {
2540                 int val = *valp;
2541                 unsigned long lval;
2542                 if (val < 0) {
2543                         *negp = -1;
2544                         lval = (unsigned long)-val;
2545                 } else {
2546                         *negp = 0;
2547                         lval = (unsigned long)val;
2548                 }
2549                 *lvalp = jiffies_to_clock_t(lval);
2550         }
2551         return 0;
2552 }
2553
2554 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2555                                             int *valp,
2556                                             int write, void *data)
2557 {
2558         if (write) {
2559                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2560         } else {
2561                 int val = *valp;
2562                 unsigned long lval;
2563                 if (val < 0) {
2564                         *negp = -1;
2565                         lval = (unsigned long)-val;
2566                 } else {
2567                         *negp = 0;
2568                         lval = (unsigned long)val;
2569                 }
2570                 *lvalp = jiffies_to_msecs(lval);
2571         }
2572         return 0;
2573 }
2574
2575 /**
2576  * proc_dointvec_jiffies - read a vector of integers as seconds
2577  * @table: the sysctl table
2578  * @write: %TRUE if this is a write to the sysctl file
2579  * @filp: the file structure
2580  * @buffer: the user buffer
2581  * @lenp: the size of the user buffer
2582  * @ppos: file position
2583  *
2584  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2585  * values from/to the user buffer, treated as an ASCII string.
2586  * The values read are assumed to be in seconds, and are converted into
2587  * jiffies.
2588  *
2589  * Returns 0 on success.
2590  */
2591 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2592                           void __user *buffer, size_t *lenp, loff_t *ppos)
2593 {
2594     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2595                             do_proc_dointvec_jiffies_conv,NULL);
2596 }
2597
2598 /**
2599  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2600  * @table: the sysctl table
2601  * @write: %TRUE if this is a write to the sysctl file
2602  * @filp: the file structure
2603  * @buffer: the user buffer
2604  * @lenp: the size of the user buffer
2605  * @ppos: pointer to the file position
2606  *
2607  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2608  * values from/to the user buffer, treated as an ASCII string.
2609  * The values read are assumed to be in 1/USER_HZ seconds, and
2610  * are converted into jiffies.
2611  *
2612  * Returns 0 on success.
2613  */
2614 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2615                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2616 {
2617     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2618                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2619 }
2620
2621 /**
2622  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2623  * @table: the sysctl table
2624  * @write: %TRUE if this is a write to the sysctl file
2625  * @filp: the file structure
2626  * @buffer: the user buffer
2627  * @lenp: the size of the user buffer
2628  * @ppos: file position
2629  * @ppos: the current position in the file
2630  *
2631  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2632  * values from/to the user buffer, treated as an ASCII string.
2633  * The values read are assumed to be in 1/1000 seconds, and
2634  * are converted into jiffies.
2635  *
2636  * Returns 0 on success.
2637  */
2638 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2639                              void __user *buffer, size_t *lenp, loff_t *ppos)
2640 {
2641         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2642                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2643 }
2644
2645 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2646                            void __user *buffer, size_t *lenp, loff_t *ppos)
2647 {
2648         struct pid *new_pid;
2649         pid_t tmp;
2650         int r;
2651
2652         tmp = pid_vnr(cad_pid);
2653
2654         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2655                                lenp, ppos, NULL, NULL);
2656         if (r || !write)
2657                 return r;
2658
2659         new_pid = find_get_pid(tmp);
2660         if (!new_pid)
2661                 return -ESRCH;
2662
2663         put_pid(xchg(&cad_pid, new_pid));
2664         return 0;
2665 }
2666
2667 #else /* CONFIG_PROC_FS */
2668
2669 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2670                   void __user *buffer, size_t *lenp, loff_t *ppos)
2671 {
2672         return -ENOSYS;
2673 }
2674
2675 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2676                   void __user *buffer, size_t *lenp, loff_t *ppos)
2677 {
2678         return -ENOSYS;
2679 }
2680
2681 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2682                     void __user *buffer, size_t *lenp, loff_t *ppos)
2683 {
2684         return -ENOSYS;
2685 }
2686
2687 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2688                     void __user *buffer, size_t *lenp, loff_t *ppos)
2689 {
2690         return -ENOSYS;
2691 }
2692
2693 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2694                     void __user *buffer, size_t *lenp, loff_t *ppos)
2695 {
2696         return -ENOSYS;
2697 }
2698
2699 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2700                              void __user *buffer, size_t *lenp, loff_t *ppos)
2701 {
2702         return -ENOSYS;
2703 }
2704
2705 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2706                     void __user *buffer, size_t *lenp, loff_t *ppos)
2707 {
2708         return -ENOSYS;
2709 }
2710
2711 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2712                                       struct file *filp,
2713                                       void __user *buffer,
2714                                       size_t *lenp, loff_t *ppos)
2715 {
2716     return -ENOSYS;
2717 }
2718
2719
2720 #endif /* CONFIG_PROC_FS */
2721
2722
2723 #ifdef CONFIG_SYSCTL_SYSCALL
2724 /*
2725  * General sysctl support routines
2726  */
2727
2728 /* The generic sysctl data routine (used if no strategy routine supplied) */
2729 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2730                 void __user *oldval, size_t __user *oldlenp,
2731                 void __user *newval, size_t newlen)
2732 {
2733         size_t len;
2734
2735         /* Get out of I don't have a variable */
2736         if (!table->data || !table->maxlen)
2737                 return -ENOTDIR;
2738
2739         if (oldval && oldlenp) {
2740                 if (get_user(len, oldlenp))
2741                         return -EFAULT;
2742                 if (len) {
2743                         if (len > table->maxlen)
2744                                 len = table->maxlen;
2745                         if (copy_to_user(oldval, table->data, len))
2746                                 return -EFAULT;
2747                         if (put_user(len, oldlenp))
2748                                 return -EFAULT;
2749                 }
2750         }
2751
2752         if (newval && newlen) {
2753                 if (newlen > table->maxlen)
2754                         newlen = table->maxlen;
2755
2756                 if (copy_from_user(table->data, newval, newlen))
2757                         return -EFAULT;
2758         }
2759         return 1;
2760 }
2761
2762 /* The generic string strategy routine: */
2763 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2764                   void __user *oldval, size_t __user *oldlenp,
2765                   void __user *newval, size_t newlen)
2766 {
2767         if (!table->data || !table->maxlen)
2768                 return -ENOTDIR;
2769
2770         if (oldval && oldlenp) {
2771                 size_t bufsize;
2772                 if (get_user(bufsize, oldlenp))
2773                         return -EFAULT;
2774                 if (bufsize) {
2775                         size_t len = strlen(table->data), copied;
2776
2777                         /* This shouldn't trigger for a well-formed sysctl */
2778                         if (len > table->maxlen)
2779                                 len = table->maxlen;
2780
2781                         /* Copy up to a max of bufsize-1 bytes of the string */
2782                         copied = (len >= bufsize) ? bufsize - 1 : len;
2783
2784                         if (copy_to_user(oldval, table->data, copied) ||
2785                             put_user(0, (char __user *)(oldval + copied)))
2786                                 return -EFAULT;
2787                         if (put_user(len, oldlenp))
2788                                 return -EFAULT;
2789                 }
2790         }
2791         if (newval && newlen) {
2792                 size_t len = newlen;
2793                 if (len > table->maxlen)
2794                         len = table->maxlen;
2795                 if(copy_from_user(table->data, newval, len))
2796                         return -EFAULT;
2797                 if (len == table->maxlen)
2798                         len--;
2799                 ((char *) table->data)[len] = 0;
2800         }
2801         return 1;
2802 }
2803
2804 /*
2805  * This function makes sure that all of the integers in the vector
2806  * are between the minimum and maximum values given in the arrays
2807  * table->extra1 and table->extra2, respectively.
2808  */
2809 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2810                 void __user *oldval, size_t __user *oldlenp,
2811                 void __user *newval, size_t newlen)
2812 {
2813
2814         if (newval && newlen) {
2815                 int __user *vec = (int __user *) newval;
2816                 int *min = (int *) table->extra1;
2817                 int *max = (int *) table->extra2;
2818                 size_t length;
2819                 int i;
2820
2821                 if (newlen % sizeof(int) != 0)
2822                         return -EINVAL;
2823
2824                 if (!table->extra1 && !table->extra2)
2825                         return 0;
2826
2827                 if (newlen > table->maxlen)
2828                         newlen = table->maxlen;
2829                 length = newlen / sizeof(int);
2830
2831                 for (i = 0; i < length; i++) {
2832                         int value;
2833                         if (get_user(value, vec + i))
2834                                 return -EFAULT;
2835                         if (min && value < min[i])
2836                                 return -EINVAL;
2837                         if (max && value > max[i])
2838                                 return -EINVAL;
2839                 }
2840         }
2841         return 0;
2842 }
2843
2844 /* Strategy function to convert jiffies to seconds */
2845 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2846                 void __user *oldval, size_t __user *oldlenp,
2847                 void __user *newval, size_t newlen)
2848 {
2849         if (oldval && oldlenp) {
2850                 size_t olen;
2851
2852                 if (get_user(olen, oldlenp))
2853                         return -EFAULT;
2854                 if (olen) {
2855                         int val;
2856
2857                         if (olen < sizeof(int))
2858                                 return -EINVAL;
2859
2860                         val = *(int *)(table->data) / HZ;
2861                         if (put_user(val, (int __user *)oldval))
2862                                 return -EFAULT;
2863                         if (put_user(sizeof(int), oldlenp))
2864                                 return -EFAULT;
2865                 }
2866         }
2867         if (newval && newlen) {
2868                 int new;
2869                 if (newlen != sizeof(int))
2870                         return -EINVAL;
2871                 if (get_user(new, (int __user *)newval))
2872                         return -EFAULT;
2873                 *(int *)(table->data) = new*HZ;
2874         }
2875         return 1;
2876 }
2877
2878 /* Strategy function to convert jiffies to seconds */
2879 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2880                 void __user *oldval, size_t __user *oldlenp,
2881                 void __user *newval, size_t newlen)
2882 {
2883         if (oldval && oldlenp) {
2884                 size_t olen;
2885
2886                 if (get_user(olen, oldlenp))
2887                         return -EFAULT;
2888                 if (olen) {
2889                         int val;
2890
2891                         if (olen < sizeof(int))
2892                                 return -EINVAL;
2893
2894                         val = jiffies_to_msecs(*(int *)(table->data));
2895                         if (put_user(val, (int __user *)oldval))
2896                                 return -EFAULT;
2897                         if (put_user(sizeof(int), oldlenp))
2898                                 return -EFAULT;
2899                 }
2900         }
2901         if (newval && newlen) {
2902                 int new;
2903                 if (newlen != sizeof(int))
2904                         return -EINVAL;
2905                 if (get_user(new, (int __user *)newval))
2906                         return -EFAULT;
2907                 *(int *)(table->data) = msecs_to_jiffies(new);
2908         }
2909         return 1;
2910 }
2911
2912
2913
2914 #else /* CONFIG_SYSCTL_SYSCALL */
2915
2916
2917 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2918 {
2919         struct __sysctl_args tmp;
2920         int error;
2921
2922         if (copy_from_user(&tmp, args, sizeof(tmp)))
2923                 return -EFAULT;
2924
2925         error = deprecated_sysctl_warning(&tmp);
2926
2927         /* If no error reading the parameters then just -ENOSYS ... */
2928         if (!error)
2929                 error = -ENOSYS;
2930
2931         return error;
2932 }
2933
2934 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2935                   void __user *oldval, size_t __user *oldlenp,
2936                   void __user *newval, size_t newlen)
2937 {
2938         return -ENOSYS;
2939 }
2940
2941 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2942                   void __user *oldval, size_t __user *oldlenp,
2943                   void __user *newval, size_t newlen)
2944 {
2945         return -ENOSYS;
2946 }
2947
2948 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2949                 void __user *oldval, size_t __user *oldlenp,
2950                 void __user *newval, size_t newlen)
2951 {
2952         return -ENOSYS;
2953 }
2954
2955 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2956                 void __user *oldval, size_t __user *oldlenp,
2957                 void __user *newval, size_t newlen)
2958 {
2959         return -ENOSYS;
2960 }
2961
2962 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2963                 void __user *oldval, size_t __user *oldlenp,
2964                 void __user *newval, size_t newlen)
2965 {
2966         return -ENOSYS;
2967 }
2968
2969 #endif /* CONFIG_SYSCTL_SYSCALL */
2970
2971 static int deprecated_sysctl_warning(struct __sysctl_args *args)
2972 {
2973         static int msg_count;
2974         int name[CTL_MAXNAME];
2975         int i;
2976
2977         /* Check args->nlen. */
2978         if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
2979                 return -ENOTDIR;
2980
2981         /* Read in the sysctl name for better debug message logging */
2982         for (i = 0; i < args->nlen; i++)
2983                 if (get_user(name[i], args->name + i))
2984                         return -EFAULT;
2985
2986         /* Ignore accesses to kernel.version */
2987         if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2988                 return 0;
2989
2990         if (msg_count < 5) {
2991                 msg_count++;
2992                 printk(KERN_INFO
2993                         "warning: process `%s' used the deprecated sysctl "
2994                         "system call with ", current->comm);
2995                 for (i = 0; i < args->nlen; i++)
2996                         printk("%d.", name[i]);
2997                 printk("\n");
2998         }
2999         return 0;
3000 }
3001
3002 /*
3003  * No sense putting this after each symbol definition, twice,
3004  * exception granted :-)
3005  */
3006 EXPORT_SYMBOL(proc_dointvec);
3007 EXPORT_SYMBOL(proc_dointvec_jiffies);
3008 EXPORT_SYMBOL(proc_dointvec_minmax);
3009 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3010 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3011 EXPORT_SYMBOL(proc_dostring);
3012 EXPORT_SYMBOL(proc_doulongvec_minmax);
3013 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3014 EXPORT_SYMBOL(register_sysctl_table);
3015 EXPORT_SYMBOL(register_sysctl_paths);
3016 EXPORT_SYMBOL(sysctl_intvec);
3017 EXPORT_SYMBOL(sysctl_jiffies);
3018 EXPORT_SYMBOL(sysctl_ms_jiffies);
3019 EXPORT_SYMBOL(sysctl_string);
3020 EXPORT_SYMBOL(sysctl_data);
3021 EXPORT_SYMBOL(unregister_sysctl_table);