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