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/capability.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/security.h>
  41 #include <linux/initrd.h>
  42 #include <linux/times.h>
  43 #include <linux/limits.h>
  44 #include <linux/dcache.h>
  45 #include <linux/syscalls.h>
  46 #include <linux/nfs_fs.h>
  47 #include <linux/acpi.h>
  48 #include <linux/reboot.h>
  49
  50 #include <asm/uaccess.h>
  51 #include <asm/processor.h>
  52
  53 #ifdef CONFIG_X86
  54 #include <asm/nmi.h>
  55 #include <asm/stacktrace.h>
  56 #endif
  57
  58 #if defined(CONFIG_SYSCTL)
  59
  60 /* External variables not in a header file. */
  61 extern int C_A_D;
  62 extern int print_fatal_signals;
  63 extern int sysctl_overcommit_memory;
  64 extern int sysctl_overcommit_ratio;
  65 extern int sysctl_panic_on_oom;
  66 extern int max_threads;
  67 extern int core_uses_pid;
  68 extern int suid_dumpable;
  69 extern char core_pattern[];
  70 extern int pid_max;
  71 extern int min_free_kbytes;
  72 extern int printk_ratelimit_jiffies;
  73 extern int printk_ratelimit_burst;
  74 extern int pid_max_min, pid_max_max;
  75 extern int sysctl_drop_caches;
  76 extern int percpu_pagelist_fraction;
  77 extern int compat_log;
  78 extern int maps_protect;
  79 extern int sysctl_stat_interval;
  80 extern int audit_argv_kb;
  81
  82 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  83 static int maxolduid = 65535;
  84 static int minolduid;
  85 static int min_percpu_pagelist_fract = 8;
  86
  87 static int ngroups_max = NGROUPS_MAX;
  88
  89 #ifdef CONFIG_KMOD
  90 extern char modprobe_path[];
  91 #endif
  92 #ifdef CONFIG_CHR_DEV_SG
  93 extern int sg_big_buff;
  94 #endif
  95
  96 #ifdef __sparc__
  97 extern char reboot_command [];
  98 extern int stop_a_enabled;
  99 extern int scons_pwroff;
 100 #endif
 101
 102 #ifdef __hppa__
 103 extern int pwrsw_enabled;
 104 extern int unaligned_enabled;
 105 #endif
 106
 107 #ifdef CONFIG_S390
 108 #ifdef CONFIG_MATHEMU
 109 extern int sysctl_ieee_emulation_warnings;
 110 #endif
 111 extern int sysctl_userprocess_debug;
 112 extern int spin_retry;
 113 #endif
 114
 115 extern int sysctl_hz_timer;
 116
 117 #ifdef CONFIG_BSD_PROCESS_ACCT
 118 extern int acct_parm[];
 119 #endif
 120
 121 #ifdef CONFIG_IA64
 122 extern int no_unaligned_warning;
 123 #endif
 124
 125 #ifdef CONFIG_RT_MUTEXES
 126 extern int max_lock_depth;
 127 #endif
 128
 129 #ifdef CONFIG_SYSCTL_SYSCALL
 130 static int parse_table(int __user *, int, void __user *, size_t __user *,
 131                 void __user *, size_t, ctl_table *);
 132 #endif
 133
 134
 135 #ifdef CONFIG_PROC_SYSCTL
 136 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
 137                   void __user *buffer, size_t *lenp, loff_t *ppos);
 138 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
 139                                void __user *buffer, size_t *lenp, loff_t *ppos);
 140 #endif
 141
 142 static ctl_table root_table[];
 143 static struct ctl_table_header root_table_header =
 144         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 145
 146 static ctl_table kern_table[];
 147 static ctl_table vm_table[];
 148 static ctl_table fs_table[];
 149 static ctl_table debug_table[];
 150 static ctl_table dev_table[];
 151 extern ctl_table random_table[];
 152 #ifdef CONFIG_UNIX98_PTYS
 153 extern ctl_table pty_table[];
 154 #endif
 155 #ifdef CONFIG_INOTIFY_USER
 156 extern ctl_table inotify_table[];
 157 #endif
 158
 159 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 160 int sysctl_legacy_va_layout;
 161 #endif
 162
 163 extern int prove_locking;
 164 extern int lock_stat;
 165
 166 /* The default sysctl tables: */
 167
 168 static ctl_table root_table[] = {
 169         {
 170                 .ctl_name       = CTL_KERN,
 171                 .procname       = "kernel",
 172                 .mode           = 0555,
 173                 .child          = kern_table,
 174         },
 175         {
 176                 .ctl_name       = CTL_VM,
 177                 .procname       = "vm",
 178                 .mode           = 0555,
 179                 .child          = vm_table,
 180         },
 181 #ifdef CONFIG_NET
 182         {
 183                 .ctl_name       = CTL_NET,
 184                 .procname       = "net",
 185                 .mode           = 0555,
 186                 .child          = net_table,
 187         },
 188 #endif
 189         {
 190                 .ctl_name       = CTL_FS,
 191                 .procname       = "fs",
 192                 .mode           = 0555,
 193                 .child          = fs_table,
 194         },
 195         {
 196                 .ctl_name       = CTL_DEBUG,
 197                 .procname       = "debug",
 198                 .mode           = 0555,
 199                 .child          = debug_table,
 200         },
 201         {
 202                 .ctl_name       = CTL_DEV,
 203                 .procname       = "dev",
 204                 .mode           = 0555,
 205                 .child          = dev_table,
 206         },
 207 /*
 208  * NOTE: do not add new entries to this table unless you have read
 209  * Documentation/sysctl/ctl_unnumbered.txt
 210  */
 211         { .ctl_name = 0 }
 212 };
 213
 214 #ifdef CONFIG_SCHED_DEBUG
 215 static unsigned long min_sched_granularity_ns = 100000;         /* 100 usecs */
 216 static unsigned long max_sched_granularity_ns = 1000000000;     /* 1 second */
 217 static unsigned long min_wakeup_granularity_ns;                 /* 0 usecs */
 218 static unsigned long max_wakeup_granularity_ns = 1000000000;    /* 1 second */
 219 #endif
 220
 221 static ctl_table kern_table[] = {
 222 #ifdef CONFIG_SCHED_DEBUG
 223         {
 224                 .ctl_name       = CTL_UNNUMBERED,
 225                 .procname       = "sched_granularity_ns",
 226                 .data           = &sysctl_sched_granularity,
 227                 .maxlen         = sizeof(unsigned int),
 228                 .mode           = 0644,
 229                 .proc_handler   = &proc_dointvec_minmax,
 230                 .strategy       = &sysctl_intvec,
 231                 .extra1         = &min_sched_granularity_ns,
 232                 .extra2         = &max_sched_granularity_ns,
 233         },
 234         {
 235                 .ctl_name       = CTL_UNNUMBERED,
 236                 .procname       = "sched_wakeup_granularity_ns",
 237                 .data           = &sysctl_sched_wakeup_granularity,
 238                 .maxlen         = sizeof(unsigned int),
 239                 .mode           = 0644,
 240                 .proc_handler   = &proc_dointvec_minmax,
 241                 .strategy       = &sysctl_intvec,
 242                 .extra1         = &min_wakeup_granularity_ns,
 243                 .extra2         = &max_wakeup_granularity_ns,
 244         },
 245         {
 246                 .ctl_name       = CTL_UNNUMBERED,
 247                 .procname       = "sched_batch_wakeup_granularity_ns",
 248                 .data           = &sysctl_sched_batch_wakeup_granularity,
 249                 .maxlen         = sizeof(unsigned int),
 250                 .mode           = 0644,
 251                 .proc_handler   = &proc_dointvec_minmax,
 252                 .strategy       = &sysctl_intvec,
 253                 .extra1         = &min_wakeup_granularity_ns,
 254                 .extra2         = &max_wakeup_granularity_ns,
 255         },
 256         {
 257                 .ctl_name       = CTL_UNNUMBERED,
 258                 .procname       = "sched_stat_granularity_ns",
 259                 .data           = &sysctl_sched_stat_granularity,
 260                 .maxlen         = sizeof(unsigned int),
 261                 .mode           = 0644,
 262                 .proc_handler   = &proc_dointvec_minmax,
 263                 .strategy       = &sysctl_intvec,
 264                 .extra1         = &min_wakeup_granularity_ns,
 265                 .extra2         = &max_wakeup_granularity_ns,
 266         },
 267         {
 268                 .ctl_name       = CTL_UNNUMBERED,
 269                 .procname       = "sched_runtime_limit_ns",
 270                 .data           = &sysctl_sched_runtime_limit,
 271                 .maxlen         = sizeof(unsigned int),
 272                 .mode           = 0644,
 273                 .proc_handler   = &proc_dointvec_minmax,
 274                 .strategy       = &sysctl_intvec,
 275                 .extra1         = &min_sched_granularity_ns,
 276                 .extra2         = &max_sched_granularity_ns,
 277         },
 278         {
 279                 .ctl_name       = CTL_UNNUMBERED,
 280                 .procname       = "sched_child_runs_first",
 281                 .data           = &sysctl_sched_child_runs_first,
 282                 .maxlen         = sizeof(unsigned int),
 283                 .mode           = 0644,
 284                 .proc_handler   = &proc_dointvec,
 285         },
 286 #ifdef CONFIG_PROVE_LOCKING
 287         {
 288                 .ctl_name       = CTL_UNNUMBERED,
 289                 .procname       = "prove_locking",
 290                 .data           = &prove_locking,
 291                 .maxlen         = sizeof(int),
 292                 .mode           = 0644,
 293                 .proc_handler   = &proc_dointvec,
 294         },
 295 #endif
 296 #ifdef CONFIG_LOCK_STAT
 297         {
 298                 .ctl_name       = CTL_UNNUMBERED,
 299                 .procname       = "lock_stat",
 300                 .data           = &lock_stat,
 301                 .maxlen         = sizeof(int),
 302                 .mode           = 0644,
 303                 .proc_handler   = &proc_dointvec,
 304         },
 305 #endif
 306         {
 307                 .ctl_name       = CTL_UNNUMBERED,
 308                 .procname       = "sched_features",
 309                 .data           = &sysctl_sched_features,
 310                 .maxlen         = sizeof(unsigned int),
 311                 .mode           = 0644,
 312                 .proc_handler   = &proc_dointvec,
 313         },
 314 #endif
 315         {
 316                 .ctl_name       = KERN_PANIC,
 317                 .procname       = "panic",
 318                 .data           = &panic_timeout,
 319                 .maxlen         = sizeof(int),
 320                 .mode           = 0644,
 321                 .proc_handler   = &proc_dointvec,
 322         },
 323         {
 324                 .ctl_name       = KERN_CORE_USES_PID,
 325                 .procname       = "core_uses_pid",
 326                 .data           = &core_uses_pid,
 327                 .maxlen         = sizeof(int),
 328                 .mode           = 0644,
 329                 .proc_handler   = &proc_dointvec,
 330         },
 331 #ifdef CONFIG_AUDITSYSCALL
 332         {
 333                 .ctl_name       = CTL_UNNUMBERED,
 334                 .procname       = "audit_argv_kb",
 335                 .data           = &audit_argv_kb,
 336                 .maxlen         = sizeof(int),
 337                 .mode           = 0644,
 338                 .proc_handler   = &proc_dointvec,
 339         },
 340 #endif
 341         {
 342                 .ctl_name       = KERN_CORE_PATTERN,
 343                 .procname       = "core_pattern",
 344                 .data           = core_pattern,
 345                 .maxlen         = CORENAME_MAX_SIZE,
 346                 .mode           = 0644,
 347                 .proc_handler   = &proc_dostring,
 348                 .strategy       = &sysctl_string,
 349         },
 350 #ifdef CONFIG_PROC_SYSCTL
 351         {
 352                 .ctl_name       = KERN_TAINTED,
 353                 .procname       = "tainted",
 354                 .data           = &tainted,
 355                 .maxlen         = sizeof(int),
 356                 .mode           = 0644,
 357                 .proc_handler   = &proc_dointvec_taint,
 358         },
 359 #endif
 360         {
 361                 .ctl_name       = KERN_CAP_BSET,
 362                 .procname       = "cap-bound",
 363                 .data           = &cap_bset,
 364                 .maxlen         = sizeof(kernel_cap_t),
 365                 .mode           = 0600,
 366                 .proc_handler   = &proc_dointvec_bset,
 367         },
 368 #ifdef CONFIG_BLK_DEV_INITRD
 369         {
 370                 .ctl_name       = KERN_REALROOTDEV,
 371                 .procname       = "real-root-dev",
 372                 .data           = &real_root_dev,
 373                 .maxlen         = sizeof(int),
 374                 .mode           = 0644,
 375                 .proc_handler   = &proc_dointvec,
 376         },
 377 #endif
 378         {
 379                 .ctl_name       = CTL_UNNUMBERED,
 380                 .procname       = "print-fatal-signals",
 381                 .data           = &print_fatal_signals,
 382                 .maxlen         = sizeof(int),
 383                 .mode           = 0644,
 384                 .proc_handler   = &proc_dointvec,
 385         },
 386 #ifdef __sparc__
 387         {
 388                 .ctl_name       = KERN_SPARC_REBOOT,
 389                 .procname       = "reboot-cmd",
 390                 .data           = reboot_command,
 391                 .maxlen         = 256,
 392                 .mode           = 0644,
 393                 .proc_handler   = &proc_dostring,
 394                 .strategy       = &sysctl_string,
 395         },
 396         {
 397                 .ctl_name       = KERN_SPARC_STOP_A,
 398                 .procname       = "stop-a",
 399                 .data           = &stop_a_enabled,
 400                 .maxlen         = sizeof (int),
 401                 .mode           = 0644,
 402                 .proc_handler   = &proc_dointvec,
 403         },
 404         {
 405                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 406                 .procname       = "scons-poweroff",
 407                 .data           = &scons_pwroff,
 408                 .maxlen         = sizeof (int),
 409                 .mode           = 0644,
 410                 .proc_handler   = &proc_dointvec,
 411         },
 412 #endif
 413 #ifdef __hppa__
 414         {
 415                 .ctl_name       = KERN_HPPA_PWRSW,
 416                 .procname       = "soft-power",
 417                 .data           = &pwrsw_enabled,
 418                 .maxlen         = sizeof (int),
 419                 .mode           = 0644,
 420                 .proc_handler   = &proc_dointvec,
 421         },
 422         {
 423                 .ctl_name       = KERN_HPPA_UNALIGNED,
 424                 .procname       = "unaligned-trap",
 425                 .data           = &unaligned_enabled,
 426                 .maxlen         = sizeof (int),
 427                 .mode           = 0644,
 428                 .proc_handler   = &proc_dointvec,
 429         },
 430 #endif
 431         {
 432                 .ctl_name       = KERN_CTLALTDEL,
 433                 .procname       = "ctrl-alt-del",
 434                 .data           = &C_A_D,
 435                 .maxlen         = sizeof(int),
 436                 .mode           = 0644,
 437                 .proc_handler   = &proc_dointvec,
 438         },
 439         {
 440                 .ctl_name       = KERN_PRINTK,
 441                 .procname       = "printk",
 442                 .data           = &console_loglevel,
 443                 .maxlen         = 4*sizeof(int),
 444                 .mode           = 0644,
 445                 .proc_handler   = &proc_dointvec,
 446         },
 447 #ifdef CONFIG_KMOD
 448         {
 449                 .ctl_name       = KERN_MODPROBE,
 450                 .procname       = "modprobe",
 451                 .data           = &modprobe_path,
 452                 .maxlen         = KMOD_PATH_LEN,
 453                 .mode           = 0644,
 454                 .proc_handler   = &proc_dostring,
 455                 .strategy       = &sysctl_string,
 456         },
 457 #endif
 458 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 459         {
 460                 .ctl_name       = KERN_HOTPLUG,
 461                 .procname       = "hotplug",
 462                 .data           = &uevent_helper,
 463                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 464                 .mode           = 0644,
 465                 .proc_handler   = &proc_dostring,
 466                 .strategy       = &sysctl_string,
 467         },
 468 #endif
 469 #ifdef CONFIG_CHR_DEV_SG
 470         {
 471                 .ctl_name       = KERN_SG_BIG_BUFF,
 472                 .procname       = "sg-big-buff",
 473                 .data           = &sg_big_buff,
 474                 .maxlen         = sizeof (int),
 475                 .mode           = 0444,
 476                 .proc_handler   = &proc_dointvec,
 477         },
 478 #endif
 479 #ifdef CONFIG_BSD_PROCESS_ACCT
 480         {
 481                 .ctl_name       = KERN_ACCT,
 482                 .procname       = "acct",
 483                 .data           = &acct_parm,
 484                 .maxlen         = 3*sizeof(int),
 485                 .mode           = 0644,
 486                 .proc_handler   = &proc_dointvec,
 487         },
 488 #endif
 489 #ifdef CONFIG_MAGIC_SYSRQ
 490         {
 491                 .ctl_name       = KERN_SYSRQ,
 492                 .procname       = "sysrq",
 493                 .data           = &__sysrq_enabled,
 494                 .maxlen         = sizeof (int),
 495                 .mode           = 0644,
 496                 .proc_handler   = &proc_dointvec,
 497         },
 498 #endif
 499 #ifdef CONFIG_PROC_SYSCTL
 500         {
 501                 .ctl_name       = KERN_CADPID,
 502                 .procname       = "cad_pid",
 503                 .data           = NULL,
 504                 .maxlen         = sizeof (int),
 505                 .mode           = 0600,
 506                 .proc_handler   = &proc_do_cad_pid,
 507         },
 508 #endif
 509         {
 510                 .ctl_name       = KERN_MAX_THREADS,
 511                 .procname       = "threads-max",
 512                 .data           = &max_threads,
 513                 .maxlen         = sizeof(int),
 514                 .mode           = 0644,
 515                 .proc_handler   = &proc_dointvec,
 516         },
 517         {
 518                 .ctl_name       = KERN_RANDOM,
 519                 .procname       = "random",
 520                 .mode           = 0555,
 521                 .child          = random_table,
 522         },
 523 #ifdef CONFIG_UNIX98_PTYS
 524         {
 525                 .ctl_name       = KERN_PTY,
 526                 .procname       = "pty",
 527                 .mode           = 0555,
 528                 .child          = pty_table,
 529         },
 530 #endif
 531         {
 532                 .ctl_name       = KERN_OVERFLOWUID,
 533                 .procname       = "overflowuid",
 534                 .data           = &overflowuid,
 535                 .maxlen         = sizeof(int),
 536                 .mode           = 0644,
 537                 .proc_handler   = &proc_dointvec_minmax,
 538                 .strategy       = &sysctl_intvec,
 539                 .extra1         = &minolduid,
 540                 .extra2         = &maxolduid,
 541         },
 542         {
 543                 .ctl_name       = KERN_OVERFLOWGID,
 544                 .procname       = "overflowgid",
 545                 .data           = &overflowgid,
 546                 .maxlen         = sizeof(int),
 547                 .mode           = 0644,
 548                 .proc_handler   = &proc_dointvec_minmax,
 549                 .strategy       = &sysctl_intvec,
 550                 .extra1         = &minolduid,
 551                 .extra2         = &maxolduid,
 552         },
 553 #ifdef CONFIG_S390
 554 #ifdef CONFIG_MATHEMU
 555         {
 556                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 557                 .procname       = "ieee_emulation_warnings",
 558                 .data           = &sysctl_ieee_emulation_warnings,
 559                 .maxlen         = sizeof(int),
 560                 .mode           = 0644,
 561                 .proc_handler   = &proc_dointvec,
 562         },
 563 #endif
 564 #ifdef CONFIG_NO_IDLE_HZ
 565         {
 566                 .ctl_name       = KERN_HZ_TIMER,
 567                 .procname       = "hz_timer",
 568                 .data           = &sysctl_hz_timer,
 569                 .maxlen         = sizeof(int),
 570                 .mode           = 0644,
 571                 .proc_handler   = &proc_dointvec,
 572         },
 573 #endif
 574         {
 575                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 576                 .procname       = "userprocess_debug",
 577                 .data           = &sysctl_userprocess_debug,
 578                 .maxlen         = sizeof(int),
 579                 .mode           = 0644,
 580                 .proc_handler   = &proc_dointvec,
 581         },
 582 #endif
 583         {
 584                 .ctl_name       = KERN_PIDMAX,
 585                 .procname       = "pid_max",
 586                 .data           = &pid_max,
 587                 .maxlen         = sizeof (int),
 588                 .mode           = 0644,
 589                 .proc_handler   = &proc_dointvec_minmax,
 590                 .strategy       = sysctl_intvec,
 591                 .extra1         = &pid_max_min,
 592                 .extra2         = &pid_max_max,
 593         },
 594         {
 595                 .ctl_name       = KERN_PANIC_ON_OOPS,
 596                 .procname       = "panic_on_oops",
 597                 .data           = &panic_on_oops,
 598                 .maxlen         = sizeof(int),
 599                 .mode           = 0644,
 600                 .proc_handler   = &proc_dointvec,
 601         },
 602         {
 603                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 604                 .procname       = "printk_ratelimit",
 605                 .data           = &printk_ratelimit_jiffies,
 606                 .maxlen         = sizeof(int),
 607                 .mode           = 0644,
 608                 .proc_handler   = &proc_dointvec_jiffies,
 609                 .strategy       = &sysctl_jiffies,
 610         },
 611         {
 612                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 613                 .procname       = "printk_ratelimit_burst",
 614                 .data           = &printk_ratelimit_burst,
 615                 .maxlen         = sizeof(int),
 616                 .mode           = 0644,
 617                 .proc_handler   = &proc_dointvec,
 618         },
 619         {
 620                 .ctl_name       = KERN_NGROUPS_MAX,
 621                 .procname       = "ngroups_max",
 622                 .data           = &ngroups_max,
 623                 .maxlen         = sizeof (int),
 624                 .mode           = 0444,
 625                 .proc_handler   = &proc_dointvec,
 626         },
 627 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 628         {
 629                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 630                 .procname       = "unknown_nmi_panic",
 631                 .data           = &unknown_nmi_panic,
 632                 .maxlen         = sizeof (int),
 633                 .mode           = 0644,
 634                 .proc_handler   = &proc_dointvec,
 635         },
 636         {
 637                 .ctl_name       = KERN_NMI_WATCHDOG,
 638                 .procname       = "nmi_watchdog",
 639                 .data           = &nmi_watchdog_enabled,
 640                 .maxlen         = sizeof (int),
 641                 .mode           = 0644,
 642                 .proc_handler   = &proc_nmi_enabled,
 643         },
 644 #endif
 645 #if defined(CONFIG_X86)
 646         {
 647                 .ctl_name       = KERN_PANIC_ON_NMI,
 648                 .procname       = "panic_on_unrecovered_nmi",
 649                 .data           = &panic_on_unrecovered_nmi,
 650                 .maxlen         = sizeof(int),
 651                 .mode           = 0644,
 652                 .proc_handler   = &proc_dointvec,
 653         },
 654         {
 655                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 656                 .procname       = "bootloader_type",
 657                 .data           = &bootloader_type,
 658                 .maxlen         = sizeof (int),
 659                 .mode           = 0444,
 660                 .proc_handler   = &proc_dointvec,
 661         },
 662         {
 663                 .ctl_name       = CTL_UNNUMBERED,
 664                 .procname       = "kstack_depth_to_print",
 665                 .data           = &kstack_depth_to_print,
 666                 .maxlen         = sizeof(int),
 667                 .mode           = 0644,
 668                 .proc_handler   = &proc_dointvec,
 669         },
 670 #endif
 671 #if defined(CONFIG_MMU)
 672         {
 673                 .ctl_name       = KERN_RANDOMIZE,
 674                 .procname       = "randomize_va_space",
 675                 .data           = &randomize_va_space,
 676                 .maxlen         = sizeof(int),
 677                 .mode           = 0644,
 678                 .proc_handler   = &proc_dointvec,
 679         },
 680 #endif
 681 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 682         {
 683                 .ctl_name       = KERN_SPIN_RETRY,
 684                 .procname       = "spin_retry",
 685                 .data           = &spin_retry,
 686                 .maxlen         = sizeof (int),
 687                 .mode           = 0644,
 688                 .proc_handler   = &proc_dointvec,
 689         },
 690 #endif
 691 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 692         {
 693                 .ctl_name       = KERN_ACPI_VIDEO_FLAGS,
 694                 .procname       = "acpi_video_flags",
 695                 .data           = &acpi_realmode_flags,
 696                 .maxlen         = sizeof (unsigned long),
 697                 .mode           = 0644,
 698                 .proc_handler   = &proc_doulongvec_minmax,
 699         },
 700 #endif
 701 #ifdef CONFIG_IA64
 702         {
 703                 .ctl_name       = KERN_IA64_UNALIGNED,
 704                 .procname       = "ignore-unaligned-usertrap",
 705                 .data           = &no_unaligned_warning,
 706                 .maxlen         = sizeof (int),
 707                 .mode           = 0644,
 708                 .proc_handler   = &proc_dointvec,
 709         },
 710 #endif
 711 #ifdef CONFIG_COMPAT
 712         {
 713                 .ctl_name       = KERN_COMPAT_LOG,
 714                 .procname       = "compat-log",
 715                 .data           = &compat_log,
 716                 .maxlen         = sizeof (int),
 717                 .mode           = 0644,
 718                 .proc_handler   = &proc_dointvec,
 719         },
 720 #endif
 721 #ifdef CONFIG_RT_MUTEXES
 722         {
 723                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 724                 .procname       = "max_lock_depth",
 725                 .data           = &max_lock_depth,
 726                 .maxlen         = sizeof(int),
 727                 .mode           = 0644,
 728                 .proc_handler   = &proc_dointvec,
 729         },
 730 #endif
 731 #ifdef CONFIG_PROC_FS
 732         {
 733                 .ctl_name       = CTL_UNNUMBERED,
 734                 .procname       = "maps_protect",
 735                 .data           = &maps_protect,
 736                 .maxlen         = sizeof(int),
 737                 .mode           = 0644,
 738                 .proc_handler   = &proc_dointvec,
 739         },
 740 #endif
 741         {
 742                 .ctl_name       = CTL_UNNUMBERED,
 743                 .procname       = "poweroff_cmd",
 744                 .data           = &poweroff_cmd,
 745                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 746                 .mode           = 0644,
 747                 .proc_handler   = &proc_dostring,
 748                 .strategy       = &sysctl_string,
 749         },
 750 /*
 751  * NOTE: do not add new entries to this table unless you have read
 752  * Documentation/sysctl/ctl_unnumbered.txt
 753  */
 754         { .ctl_name = 0 }
 755 };
 756
 757 /* Constants for minimum and maximum testing in vm_table.
 758    We use these as one-element integer vectors. */
 759 static int zero;
 760 static int two = 2;
 761 static int one_hundred = 100;
 762
 763
 764 static ctl_table vm_table[] = {
 765         {
 766                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 767                 .procname       = "overcommit_memory",
 768                 .data           = &sysctl_overcommit_memory,
 769                 .maxlen         = sizeof(sysctl_overcommit_memory),
 770                 .mode           = 0644,
 771                 .proc_handler   = &proc_dointvec,
 772         },
 773         {
 774                 .ctl_name       = VM_PANIC_ON_OOM,
 775                 .procname       = "panic_on_oom",
 776                 .data           = &sysctl_panic_on_oom,
 777                 .maxlen         = sizeof(sysctl_panic_on_oom),
 778                 .mode           = 0644,
 779                 .proc_handler   = &proc_dointvec,
 780         },
 781         {
 782                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 783                 .procname       = "overcommit_ratio",
 784                 .data           = &sysctl_overcommit_ratio,
 785                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 786                 .mode           = 0644,
 787                 .proc_handler   = &proc_dointvec,
 788         },
 789         {
 790                 .ctl_name       = VM_PAGE_CLUSTER,
 791                 .procname       = "page-cluster",
 792                 .data           = &page_cluster,
 793                 .maxlen         = sizeof(int),
 794                 .mode           = 0644,
 795                 .proc_handler   = &proc_dointvec,
 796         },
 797         {
 798                 .ctl_name       = VM_DIRTY_BACKGROUND,
 799                 .procname       = "dirty_background_ratio",
 800                 .data           = &dirty_background_ratio,
 801                 .maxlen         = sizeof(dirty_background_ratio),
 802                 .mode           = 0644,
 803                 .proc_handler   = &proc_dointvec_minmax,
 804                 .strategy       = &sysctl_intvec,
 805                 .extra1         = &zero,
 806                 .extra2         = &one_hundred,
 807         },
 808         {
 809                 .ctl_name       = VM_DIRTY_RATIO,
 810                 .procname       = "dirty_ratio",
 811                 .data           = &vm_dirty_ratio,
 812                 .maxlen         = sizeof(vm_dirty_ratio),
 813                 .mode           = 0644,
 814                 .proc_handler   = &proc_dointvec_minmax,
 815                 .strategy       = &sysctl_intvec,
 816                 .extra1         = &zero,
 817                 .extra2         = &one_hundred,
 818         },
 819         {
 820                 .ctl_name       = VM_DIRTY_WB_CS,
 821                 .procname       = "dirty_writeback_centisecs",
 822                 .data           = &dirty_writeback_interval,
 823                 .maxlen         = sizeof(dirty_writeback_interval),
 824                 .mode           = 0644,
 825                 .proc_handler   = &dirty_writeback_centisecs_handler,
 826         },
 827         {
 828                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 829                 .procname       = "dirty_expire_centisecs",
 830                 .data           = &dirty_expire_interval,
 831                 .maxlen         = sizeof(dirty_expire_interval),
 832                 .mode           = 0644,
 833                 .proc_handler   = &proc_dointvec_userhz_jiffies,
 834         },
 835         {
 836                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 837                 .procname       = "nr_pdflush_threads",
 838                 .data           = &nr_pdflush_threads,
 839                 .maxlen         = sizeof nr_pdflush_threads,
 840                 .mode           = 0444 /* read-only*/,
 841                 .proc_handler   = &proc_dointvec,
 842         },
 843         {
 844                 .ctl_name       = VM_SWAPPINESS,
 845                 .procname       = "swappiness",
 846                 .data           = &vm_swappiness,
 847                 .maxlen         = sizeof(vm_swappiness),
 848                 .mode           = 0644,
 849                 .proc_handler   = &proc_dointvec_minmax,
 850                 .strategy       = &sysctl_intvec,
 851                 .extra1         = &zero,
 852                 .extra2         = &one_hundred,
 853         },
 854 #ifdef CONFIG_HUGETLB_PAGE
 855          {
 856                 .ctl_name       = VM_HUGETLB_PAGES,
 857                 .procname       = "nr_hugepages",
 858                 .data           = &max_huge_pages,
 859                 .maxlen         = sizeof(unsigned long),
 860                 .mode           = 0644,
 861                 .proc_handler   = &hugetlb_sysctl_handler,
 862                 .extra1         = (void *)&hugetlb_zero,
 863                 .extra2         = (void *)&hugetlb_infinity,
 864          },
 865          {
 866                 .ctl_name       = VM_HUGETLB_GROUP,
 867                 .procname       = "hugetlb_shm_group",
 868                 .data           = &sysctl_hugetlb_shm_group,
 869                 .maxlen         = sizeof(gid_t),
 870                 .mode           = 0644,
 871                 .proc_handler   = &proc_dointvec,
 872          },
 873          {
 874                 .ctl_name       = CTL_UNNUMBERED,
 875                 .procname       = "hugepages_treat_as_movable",
 876                 .data           = &hugepages_treat_as_movable,
 877                 .maxlen         = sizeof(int),
 878                 .mode           = 0644,
 879                 .proc_handler   = &hugetlb_treat_movable_handler,
 880         },
 881 #endif
 882         {
 883                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 884                 .procname       = "lowmem_reserve_ratio",
 885                 .data           = &sysctl_lowmem_reserve_ratio,
 886                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 887                 .mode           = 0644,
 888                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 889                 .strategy       = &sysctl_intvec,
 890         },
 891         {
 892                 .ctl_name       = VM_DROP_PAGECACHE,
 893                 .procname       = "drop_caches",
 894                 .data           = &sysctl_drop_caches,
 895                 .maxlen         = sizeof(int),
 896                 .mode           = 0644,
 897                 .proc_handler   = drop_caches_sysctl_handler,
 898                 .strategy       = &sysctl_intvec,
 899         },
 900         {
 901                 .ctl_name       = VM_MIN_FREE_KBYTES,
 902                 .procname       = "min_free_kbytes",
 903                 .data           = &min_free_kbytes,
 904                 .maxlen         = sizeof(min_free_kbytes),
 905                 .mode           = 0644,
 906                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 907                 .strategy       = &sysctl_intvec,
 908                 .extra1         = &zero,
 909         },
 910         {
 911                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
 912                 .procname       = "percpu_pagelist_fraction",
 913                 .data           = &percpu_pagelist_fraction,
 914                 .maxlen         = sizeof(percpu_pagelist_fraction),
 915                 .mode           = 0644,
 916                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
 917                 .strategy       = &sysctl_intvec,
 918                 .extra1         = &min_percpu_pagelist_fract,
 919         },
 920 #ifdef CONFIG_MMU
 921         {
 922                 .ctl_name       = VM_MAX_MAP_COUNT,
 923                 .procname       = "max_map_count",
 924                 .data           = &sysctl_max_map_count,
 925                 .maxlen         = sizeof(sysctl_max_map_count),
 926                 .mode           = 0644,
 927                 .proc_handler   = &proc_dointvec
 928         },
 929 #endif
 930         {
 931                 .ctl_name       = VM_LAPTOP_MODE,
 932                 .procname       = "laptop_mode",
 933                 .data           = &laptop_mode,
 934                 .maxlen         = sizeof(laptop_mode),
 935                 .mode           = 0644,
 936                 .proc_handler   = &proc_dointvec_jiffies,
 937                 .strategy       = &sysctl_jiffies,
 938         },
 939         {
 940                 .ctl_name       = VM_BLOCK_DUMP,
 941                 .procname       = "block_dump",
 942                 .data           = &block_dump,
 943                 .maxlen         = sizeof(block_dump),
 944                 .mode           = 0644,
 945                 .proc_handler   = &proc_dointvec,
 946                 .strategy       = &sysctl_intvec,
 947                 .extra1         = &zero,
 948         },
 949         {
 950                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 951                 .procname       = "vfs_cache_pressure",
 952                 .data           = &sysctl_vfs_cache_pressure,
 953                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 954                 .mode           = 0644,
 955                 .proc_handler   = &proc_dointvec,
 956                 .strategy       = &sysctl_intvec,
 957                 .extra1         = &zero,
 958         },
 959 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 960         {
 961                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 962                 .procname       = "legacy_va_layout",
 963                 .data           = &sysctl_legacy_va_layout,
 964                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 965                 .mode           = 0644,
 966                 .proc_handler   = &proc_dointvec,
 967                 .strategy       = &sysctl_intvec,
 968                 .extra1         = &zero,
 969         },
 970 #endif
 971 #ifdef CONFIG_NUMA
 972         {
 973                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
 974                 .procname       = "zone_reclaim_mode",
 975                 .data           = &zone_reclaim_mode,
 976                 .maxlen         = sizeof(zone_reclaim_mode),
 977                 .mode           = 0644,
 978                 .proc_handler   = &proc_dointvec,
 979                 .strategy       = &sysctl_intvec,
 980                 .extra1         = &zero,
 981         },
 982         {
 983                 .ctl_name       = VM_MIN_UNMAPPED,
 984                 .procname       = "min_unmapped_ratio",
 985                 .data           = &sysctl_min_unmapped_ratio,
 986                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
 987                 .mode           = 0644,
 988                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
 989                 .strategy       = &sysctl_intvec,
 990                 .extra1         = &zero,
 991                 .extra2         = &one_hundred,
 992         },
 993         {
 994                 .ctl_name       = VM_MIN_SLAB,
 995                 .procname       = "min_slab_ratio",
 996                 .data           = &sysctl_min_slab_ratio,
 997                 .maxlen         = sizeof(sysctl_min_slab_ratio),
 998                 .mode           = 0644,
 999                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1000                 .strategy       = &sysctl_intvec,
1001                 .extra1         = &zero,
1002                 .extra2         = &one_hundred,
1003         },
1004 #endif
1005 #ifdef CONFIG_SMP
1006         {
1007                 .ctl_name       = CTL_UNNUMBERED,
1008                 .procname       = "stat_interval",
1009                 .data           = &sysctl_stat_interval,
1010                 .maxlen         = sizeof(sysctl_stat_interval),
1011                 .mode           = 0644,
1012                 .proc_handler   = &proc_dointvec_jiffies,
1013                 .strategy       = &sysctl_jiffies,
1014         },
1015 #endif
1016 #ifdef CONFIG_SECURITY
1017         {
1018                 .ctl_name       = CTL_UNNUMBERED,
1019                 .procname       = "mmap_min_addr",
1020                 .data           = &mmap_min_addr,
1021                 .maxlen         = sizeof(unsigned long),
1022                 .mode           = 0644,
1023                 .proc_handler   = &proc_doulongvec_minmax,
1024         },
1025 #endif
1026 #ifdef CONFIG_NUMA
1027         {
1028                 .ctl_name       = CTL_UNNUMBERED,
1029                 .procname       = "numa_zonelist_order",
1030                 .data           = &numa_zonelist_order,
1031                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1032                 .mode           = 0644,
1033                 .proc_handler   = &numa_zonelist_order_handler,
1034                 .strategy       = &sysctl_string,
1035         },
1036 #endif
1037 #if defined(CONFIG_X86_32) || \
1038    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1039         {
1040                 .ctl_name       = VM_VDSO_ENABLED,
1041                 .procname       = "vdso_enabled",
1042                 .data           = &vdso_enabled,
1043                 .maxlen         = sizeof(vdso_enabled),
1044                 .mode           = 0644,
1045                 .proc_handler   = &proc_dointvec,
1046                 .strategy       = &sysctl_intvec,
1047                 .extra1         = &zero,
1048         },
1049 #endif
1050 /*
1051  * NOTE: do not add new entries to this table unless you have read
1052  * Documentation/sysctl/ctl_unnumbered.txt
1053  */
1054         { .ctl_name = 0 }
1055 };
1056
1057 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1058 static ctl_table binfmt_misc_table[] = {
1059         { .ctl_name = 0 }
1060 };
1061 #endif
1062
1063 static ctl_table fs_table[] = {
1064         {
1065                 .ctl_name       = FS_NRINODE,
1066                 .procname       = "inode-nr",
1067                 .data           = &inodes_stat,
1068                 .maxlen         = 2*sizeof(int),
1069                 .mode           = 0444,
1070                 .proc_handler   = &proc_dointvec,
1071         },
1072         {
1073                 .ctl_name       = FS_STATINODE,
1074                 .procname       = "inode-state",
1075                 .data           = &inodes_stat,
1076                 .maxlen         = 7*sizeof(int),
1077                 .mode           = 0444,
1078                 .proc_handler   = &proc_dointvec,
1079         },
1080         {
1081                 .ctl_name       = FS_NRFILE,
1082                 .procname       = "file-nr",
1083                 .data           = &files_stat,
1084                 .maxlen         = 3*sizeof(int),
1085                 .mode           = 0444,
1086                 .proc_handler   = &proc_nr_files,
1087         },
1088         {
1089                 .ctl_name       = FS_MAXFILE,
1090                 .procname       = "file-max",
1091                 .data           = &files_stat.max_files,
1092                 .maxlen         = sizeof(int),
1093                 .mode           = 0644,
1094                 .proc_handler   = &proc_dointvec,
1095         },
1096         {
1097                 .ctl_name       = FS_DENTRY,
1098                 .procname       = "dentry-state",
1099                 .data           = &dentry_stat,
1100                 .maxlen         = 6*sizeof(int),
1101                 .mode           = 0444,
1102                 .proc_handler   = &proc_dointvec,
1103         },
1104         {
1105                 .ctl_name       = FS_OVERFLOWUID,
1106                 .procname       = "overflowuid",
1107                 .data           = &fs_overflowuid,
1108                 .maxlen         = sizeof(int),
1109                 .mode           = 0644,
1110                 .proc_handler   = &proc_dointvec_minmax,
1111                 .strategy       = &sysctl_intvec,
1112                 .extra1         = &minolduid,
1113                 .extra2         = &maxolduid,
1114         },
1115         {
1116                 .ctl_name       = FS_OVERFLOWGID,
1117                 .procname       = "overflowgid",
1118                 .data           = &fs_overflowgid,
1119                 .maxlen         = sizeof(int),
1120                 .mode           = 0644,
1121                 .proc_handler   = &proc_dointvec_minmax,
1122                 .strategy       = &sysctl_intvec,
1123                 .extra1         = &minolduid,
1124                 .extra2         = &maxolduid,
1125         },
1126         {
1127                 .ctl_name       = FS_LEASES,
1128                 .procname       = "leases-enable",
1129                 .data           = &leases_enable,
1130                 .maxlen         = sizeof(int),
1131                 .mode           = 0644,
1132                 .proc_handler   = &proc_dointvec,
1133         },
1134 #ifdef CONFIG_DNOTIFY
1135         {
1136                 .ctl_name       = FS_DIR_NOTIFY,
1137                 .procname       = "dir-notify-enable",
1138                 .data           = &dir_notify_enable,
1139                 .maxlen         = sizeof(int),
1140                 .mode           = 0644,
1141                 .proc_handler   = &proc_dointvec,
1142         },
1143 #endif
1144 #ifdef CONFIG_MMU
1145         {
1146                 .ctl_name       = FS_LEASE_TIME,
1147                 .procname       = "lease-break-time",
1148                 .data           = &lease_break_time,
1149                 .maxlen         = sizeof(int),
1150                 .mode           = 0644,
1151                 .proc_handler   = &proc_dointvec_minmax,
1152                 .strategy       = &sysctl_intvec,
1153                 .extra1         = &zero,
1154                 .extra2         = &two,
1155         },
1156         {
1157                 .ctl_name       = FS_AIO_NR,
1158                 .procname       = "aio-nr",
1159                 .data           = &aio_nr,
1160                 .maxlen         = sizeof(aio_nr),
1161                 .mode           = 0444,
1162                 .proc_handler   = &proc_doulongvec_minmax,
1163         },
1164         {
1165                 .ctl_name       = FS_AIO_MAX_NR,
1166                 .procname       = "aio-max-nr",
1167                 .data           = &aio_max_nr,
1168                 .maxlen         = sizeof(aio_max_nr),
1169                 .mode           = 0644,
1170                 .proc_handler   = &proc_doulongvec_minmax,
1171         },
1172 #ifdef CONFIG_INOTIFY_USER
1173         {
1174                 .ctl_name       = FS_INOTIFY,
1175                 .procname       = "inotify",
1176                 .mode           = 0555,
1177                 .child          = inotify_table,
1178         },
1179 #endif
1180 #endif
1181         {
1182                 .ctl_name       = KERN_SETUID_DUMPABLE,
1183                 .procname       = "suid_dumpable",
1184                 .data           = &suid_dumpable,
1185                 .maxlen         = sizeof(int),
1186                 .mode           = 0644,
1187                 .proc_handler   = &proc_dointvec,
1188         },
1189 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1190         {
1191                 .ctl_name       = CTL_UNNUMBERED,
1192                 .procname       = "binfmt_misc",
1193                 .mode           = 0555,
1194                 .child          = binfmt_misc_table,
1195         },
1196 #endif
1197 /*
1198  * NOTE: do not add new entries to this table unless you have read
1199  * Documentation/sysctl/ctl_unnumbered.txt
1200  */
1201         { .ctl_name = 0 }
1202 };
1203
1204 static ctl_table debug_table[] = {
1205 #ifdef CONFIG_X86
1206         {
1207                 .ctl_name       = CTL_UNNUMBERED,
1208                 .procname       = "exception-trace",
1209                 .data           = &show_unhandled_signals,
1210                 .maxlen         = sizeof(int),
1211                 .mode           = 0644,
1212                 .proc_handler   = proc_dointvec
1213         },
1214 #endif
1215         { .ctl_name = 0 }
1216 };
1217
1218 static ctl_table dev_table[] = {
1219         { .ctl_name = 0 }
1220 };
1221
1222 static DEFINE_SPINLOCK(sysctl_lock);
1223
1224 /* called under sysctl_lock */
1225 static int use_table(struct ctl_table_header *p)
1226 {
1227         if (unlikely(p->unregistering))
1228                 return 0;
1229         p->used++;
1230         return 1;
1231 }
1232
1233 /* called under sysctl_lock */
1234 static void unuse_table(struct ctl_table_header *p)
1235 {
1236         if (!--p->used)
1237                 if (unlikely(p->unregistering))
1238                         complete(p->unregistering);
1239 }
1240
1241 /* called under sysctl_lock, will reacquire if has to wait */
1242 static void start_unregistering(struct ctl_table_header *p)
1243 {
1244         /*
1245          * if p->used is 0, nobody will ever touch that entry again;
1246          * we'll eliminate all paths to it before dropping sysctl_lock
1247          */
1248         if (unlikely(p->used)) {
1249                 struct completion wait;
1250                 init_completion(&wait);
1251                 p->unregistering = &wait;
1252                 spin_unlock(&sysctl_lock);
1253                 wait_for_completion(&wait);
1254                 spin_lock(&sysctl_lock);
1255         }
1256         /*
1257          * do not remove from the list until nobody holds it; walking the
1258          * list in do_sysctl() relies on that.
1259          */
1260         list_del_init(&p->ctl_entry);
1261 }
1262
1263 void sysctl_head_finish(struct ctl_table_header *head)
1264 {
1265         if (!head)
1266                 return;
1267         spin_lock(&sysctl_lock);
1268         unuse_table(head);
1269         spin_unlock(&sysctl_lock);
1270 }
1271
1272 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1273 {
1274         struct ctl_table_header *head;
1275         struct list_head *tmp;
1276         spin_lock(&sysctl_lock);
1277         if (prev) {
1278                 tmp = &prev->ctl_entry;
1279                 unuse_table(prev);
1280                 goto next;
1281         }
1282         tmp = &root_table_header.ctl_entry;
1283         for (;;) {
1284                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1285
1286                 if (!use_table(head))
1287                         goto next;
1288                 spin_unlock(&sysctl_lock);
1289                 return head;
1290         next:
1291                 tmp = tmp->next;
1292                 if (tmp == &root_table_header.ctl_entry)
1293                         break;
1294         }
1295         spin_unlock(&sysctl_lock);
1296         return NULL;
1297 }
1298
1299 #ifdef CONFIG_SYSCTL_SYSCALL
1300 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1301                void __user *newval, size_t newlen)
1302 {
1303         struct ctl_table_header *head;
1304         int error = -ENOTDIR;
1305
1306         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1307                 return -ENOTDIR;
1308         if (oldval) {
1309                 int old_len;
1310                 if (!oldlenp || get_user(old_len, oldlenp))
1311                         return -EFAULT;
1312         }
1313
1314         for (head = sysctl_head_next(NULL); head;
1315                         head = sysctl_head_next(head)) {
1316                 error = parse_table(name, nlen, oldval, oldlenp,
1317                                         newval, newlen, head->ctl_table);
1318                 if (error != -ENOTDIR) {
1319                         sysctl_head_finish(head);
1320                         break;
1321                 }
1322         }
1323         return error;
1324 }
1325
1326 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1327 {
1328         struct __sysctl_args tmp;
1329         int error;
1330
1331         if (copy_from_user(&tmp, args, sizeof(tmp)))
1332                 return -EFAULT;
1333
1334         lock_kernel();
1335         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1336                           tmp.newval, tmp.newlen);
1337         unlock_kernel();
1338         return error;
1339 }
1340 #endif /* CONFIG_SYSCTL_SYSCALL */
1341
1342 /*
1343  * sysctl_perm does NOT grant the superuser all rights automatically, because
1344  * some sysctl variables are readonly even to root.
1345  */
1346
1347 static int test_perm(int mode, int op)
1348 {
1349         if (!current->euid)
1350                 mode >>= 6;
1351         else if (in_egroup_p(0))
1352                 mode >>= 3;
1353         if ((mode & op & 0007) == op)
1354                 return 0;
1355         return -EACCES;
1356 }
1357
1358 int sysctl_perm(ctl_table *table, int op)
1359 {
1360         int error;
1361         error = security_sysctl(table, op);
1362         if (error)
1363                 return error;
1364         return test_perm(table->mode, op);
1365 }
1366
1367 #ifdef CONFIG_SYSCTL_SYSCALL
1368 static int parse_table(int __user *name, int nlen,
1369                        void __user *oldval, size_t __user *oldlenp,
1370                        void __user *newval, size_t newlen,
1371                        ctl_table *table)
1372 {
1373         int n;
1374 repeat:
1375         if (!nlen)
1376                 return -ENOTDIR;
1377         if (get_user(n, name))
1378                 return -EFAULT;
1379         for ( ; table->ctl_name || table->procname; table++) {
1380                 if (!table->ctl_name)
1381                         continue;
1382                 if (n == table->ctl_name) {
1383                         int error;
1384                         if (table->child) {
1385                                 if (sysctl_perm(table, 001))
1386                                         return -EPERM;
1387                                 name++;
1388                                 nlen--;
1389                                 table = table->child;
1390                                 goto repeat;
1391                         }
1392                         error = do_sysctl_strategy(table, name, nlen,
1393                                                    oldval, oldlenp,
1394                                                    newval, newlen);
1395                         return error;
1396                 }
1397         }
1398         return -ENOTDIR;
1399 }
1400
1401 /* Perform the actual read/write of a sysctl table entry. */
1402 int do_sysctl_strategy (ctl_table *table,
1403                         int __user *name, int nlen,
1404                         void __user *oldval, size_t __user *oldlenp,
1405                         void __user *newval, size_t newlen)
1406 {
1407         int op = 0, rc;
1408         size_t len;
1409
1410         if (oldval)
1411                 op |= 004;
1412         if (newval)
1413                 op |= 002;
1414         if (sysctl_perm(table, op))
1415                 return -EPERM;
1416
1417         if (table->strategy) {
1418                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1419                                      newval, newlen);
1420                 if (rc < 0)
1421                         return rc;
1422                 if (rc > 0)
1423                         return 0;
1424         }
1425
1426         /* If there is no strategy routine, or if the strategy returns
1427          * zero, proceed with automatic r/w */
1428         if (table->data && table->maxlen) {
1429                 if (oldval && oldlenp) {
1430                         if (get_user(len, oldlenp))
1431                                 return -EFAULT;
1432                         if (len) {
1433                                 if (len > table->maxlen)
1434                                         len = table->maxlen;
1435                                 if(copy_to_user(oldval, table->data, len))
1436                                         return -EFAULT;
1437                                 if(put_user(len, oldlenp))
1438                                         return -EFAULT;
1439                         }
1440                 }
1441                 if (newval && newlen) {
1442                         len = newlen;
1443                         if (len > table->maxlen)
1444                                 len = table->maxlen;
1445                         if(copy_from_user(table->data, newval, len))
1446                                 return -EFAULT;
1447                 }
1448         }
1449         return 0;
1450 }
1451 #endif /* CONFIG_SYSCTL_SYSCALL */
1452
1453 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1454 {
1455         for (; table->ctl_name || table->procname; table++) {
1456                 table->parent = parent;
1457                 if (table->child)
1458                         sysctl_set_parent(table, table->child);
1459         }
1460 }
1461
1462 static __init int sysctl_init(void)
1463 {
1464         sysctl_set_parent(NULL, root_table);
1465         return 0;
1466 }
1467
1468 core_initcall(sysctl_init);
1469
1470 /**
1471  * register_sysctl_table - register a sysctl hierarchy
1472  * @table: the top-level table structure
1473  *
1474  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1475  * array. An entry with a ctl_name of 0 terminates the table.
1476  *
1477  * The members of the &ctl_table structure are used as follows:
1478  *
1479  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1480  *            must be unique within that level of sysctl
1481  *
1482  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1483  *            enter a sysctl file
1484  *
1485  * data - a pointer to data for use by proc_handler
1486  *
1487  * maxlen - the maximum size in bytes of the data
1488  *
1489  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1490  *
1491  * child - a pointer to the child sysctl table if this entry is a directory, or
1492  *         %NULL.
1493  *
1494  * proc_handler - the text handler routine (described below)
1495  *
1496  * strategy - the strategy routine (described below)
1497  *
1498  * de - for internal use by the sysctl routines
1499  *
1500  * extra1, extra2 - extra pointers usable by the proc handler routines
1501  *
1502  * Leaf nodes in the sysctl tree will be represented by a single file
1503  * under /proc; non-leaf nodes will be represented by directories.
1504  *
1505  * sysctl(2) can automatically manage read and write requests through
1506  * the sysctl table.  The data and maxlen fields of the ctl_table
1507  * struct enable minimal validation of the values being written to be
1508  * performed, and the mode field allows minimal authentication.
1509  *
1510  * More sophisticated management can be enabled by the provision of a
1511  * strategy routine with the table entry.  This will be called before
1512  * any automatic read or write of the data is performed.
1513  *
1514  * The strategy routine may return
1515  *
1516  * < 0 - Error occurred (error is passed to user process)
1517  *
1518  * 0   - OK - proceed with automatic read or write.
1519  *
1520  * > 0 - OK - read or write has been done by the strategy routine, so
1521  *       return immediately.
1522  *
1523  * There must be a proc_handler routine for any terminal nodes
1524  * mirrored under /proc/sys (non-terminals are handled by a built-in
1525  * directory handler).  Several default handlers are available to
1526  * cover common cases -
1527  *
1528  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1529  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1530  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1531  *
1532  * It is the handler's job to read the input buffer from user memory
1533  * and process it. The handler should return 0 on success.
1534  *
1535  * This routine returns %NULL on a failure to register, and a pointer
1536  * to the table header on success.
1537  */
1538 struct ctl_table_header *register_sysctl_table(ctl_table * table)
1539 {
1540         struct ctl_table_header *tmp;
1541         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1542         if (!tmp)
1543                 return NULL;
1544         tmp->ctl_table = table;
1545         INIT_LIST_HEAD(&tmp->ctl_entry);
1546         tmp->used = 0;
1547         tmp->unregistering = NULL;
1548         sysctl_set_parent(NULL, table);
1549         spin_lock(&sysctl_lock);
1550         list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1551         spin_unlock(&sysctl_lock);
1552         return tmp;
1553 }
1554
1555 /**
1556  * unregister_sysctl_table - unregister a sysctl table hierarchy
1557  * @header: the header returned from register_sysctl_table
1558  *
1559  * Unregisters the sysctl table and all children. proc entries may not
1560  * actually be removed until they are no longer used by anyone.
1561  */
1562 void unregister_sysctl_table(struct ctl_table_header * header)
1563 {
1564         might_sleep();
1565         spin_lock(&sysctl_lock);
1566         start_unregistering(header);
1567         spin_unlock(&sysctl_lock);
1568         kfree(header);
1569 }
1570
1571 #else /* !CONFIG_SYSCTL */
1572 struct ctl_table_header *register_sysctl_table(ctl_table * table)
1573 {
1574         return NULL;
1575 }
1576
1577 void unregister_sysctl_table(struct ctl_table_header * table)
1578 {
1579 }
1580
1581 #endif /* CONFIG_SYSCTL */
1582
1583 /*
1584  * /proc/sys support
1585  */
1586
1587 #ifdef CONFIG_PROC_SYSCTL
1588
1589 static int _proc_do_string(void* data, int maxlen, int write,
1590                            struct file *filp, void __user *buffer,
1591                            size_t *lenp, loff_t *ppos)
1592 {
1593         size_t len;
1594         char __user *p;
1595         char c;
1596
1597         if (!data || !maxlen || !*lenp) {
1598                 *lenp = 0;
1599                 return 0;
1600         }
1601
1602         if (write) {
1603                 len = 0;
1604                 p = buffer;
1605                 while (len < *lenp) {
1606                         if (get_user(c, p++))
1607                                 return -EFAULT;
1608                         if (c == 0 || c == '\n')
1609                                 break;
1610                         len++;
1611                 }
1612                 if (len >= maxlen)
1613                         len = maxlen-1;
1614                 if(copy_from_user(data, buffer, len))
1615                         return -EFAULT;
1616                 ((char *) data)[len] = 0;
1617                 *ppos += *lenp;
1618         } else {
1619                 len = strlen(data);
1620                 if (len > maxlen)
1621                         len = maxlen;
1622
1623                 if (*ppos > len) {
1624                         *lenp = 0;
1625                         return 0;
1626                 }
1627
1628                 data += *ppos;
1629                 len  -= *ppos;
1630
1631                 if (len > *lenp)
1632                         len = *lenp;
1633                 if (len)
1634                         if(copy_to_user(buffer, data, len))
1635                                 return -EFAULT;
1636                 if (len < *lenp) {
1637                         if(put_user('\n', ((char __user *) buffer) + len))
1638                                 return -EFAULT;
1639                         len++;
1640                 }
1641                 *lenp = len;
1642                 *ppos += len;
1643         }
1644         return 0;
1645 }
1646
1647 /**
1648  * proc_dostring - read a string sysctl
1649  * @table: the sysctl table
1650  * @write: %TRUE if this is a write to the sysctl file
1651  * @filp: the file structure
1652  * @buffer: the user buffer
1653  * @lenp: the size of the user buffer
1654  * @ppos: file position
1655  *
1656  * Reads/writes a string from/to the user buffer. If the kernel
1657  * buffer provided is not large enough to hold the string, the
1658  * string is truncated. The copied string is %NULL-terminated.
1659  * If the string is being read by the user process, it is copied
1660  * and a newline '\n' is added. It is truncated if the buffer is
1661  * not large enough.
1662  *
1663  * Returns 0 on success.
1664  */
1665 int proc_dostring(ctl_table *table, int write, struct file *filp,
1666                   void __user *buffer, size_t *lenp, loff_t *ppos)
1667 {
1668         return _proc_do_string(table->data, table->maxlen, write, filp,
1669                                buffer, lenp, ppos);
1670 }
1671
1672
1673 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1674                                  int *valp,
1675                                  int write, void *data)
1676 {
1677         if (write) {
1678                 *valp = *negp ? -*lvalp : *lvalp;
1679         } else {
1680                 int val = *valp;
1681                 if (val < 0) {
1682                         *negp = -1;
1683                         *lvalp = (unsigned long)-val;
1684                 } else {
1685                         *negp = 0;
1686                         *lvalp = (unsigned long)val;
1687                 }
1688         }
1689         return 0;
1690 }
1691
1692 static int __do_proc_dointvec(void *tbl_data, ctl_table *table,
1693                   int write, struct file *filp, void __user *buffer,
1694                   size_t *lenp, loff_t *ppos,
1695                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1696                               int write, void *data),
1697                   void *data)
1698 {
1699 #define TMPBUFLEN 21
1700         int *i, vleft, first=1, neg, val;
1701         unsigned long lval;
1702         size_t left, len;
1703
1704         char buf[TMPBUFLEN], *p;
1705         char __user *s = buffer;
1706
1707         if (!tbl_data || !table->maxlen || !*lenp ||
1708             (*ppos && !write)) {
1709                 *lenp = 0;
1710                 return 0;
1711         }
1712
1713         i = (int *) tbl_data;
1714         vleft = table->maxlen / sizeof(*i);
1715         left = *lenp;
1716
1717         if (!conv)
1718                 conv = do_proc_dointvec_conv;
1719
1720         for (; left && vleft--; i++, first=0) {
1721                 if (write) {
1722                         while (left) {
1723                                 char c;
1724                                 if (get_user(c, s))
1725                                         return -EFAULT;
1726                                 if (!isspace(c))
1727                                         break;
1728                                 left--;
1729                                 s++;
1730                         }
1731                         if (!left)
1732                                 break;
1733                         neg = 0;
1734                         len = left;
1735                         if (len > sizeof(buf) - 1)
1736                                 len = sizeof(buf) - 1;
1737                         if (copy_from_user(buf, s, len))
1738                                 return -EFAULT;
1739                         buf[len] = 0;
1740                         p = buf;
1741                         if (*p == '-' && left > 1) {
1742                                 neg = 1;
1743                                 p++;
1744                         }
1745                         if (*p < '0' || *p > '9')
1746                                 break;
1747
1748                         lval = simple_strtoul(p, &p, 0);
1749
1750                         len = p-buf;
1751                         if ((len < left) && *p && !isspace(*p))
1752                                 break;
1753                         if (neg)
1754                                 val = -val;
1755                         s += len;
1756                         left -= len;
1757
1758                         if (conv(&neg, &lval, i, 1, data))
1759                                 break;
1760                 } else {
1761                         p = buf;
1762                         if (!first)
1763                                 *p++ = '\t';
1764
1765                         if (conv(&neg, &lval, i, 0, data))
1766                                 break;
1767
1768                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1769                         len = strlen(buf);
1770                         if (len > left)
1771                                 len = left;
1772                         if(copy_to_user(s, buf, len))
1773                                 return -EFAULT;
1774                         left -= len;
1775                         s += len;
1776                 }
1777         }
1778
1779         if (!write && !first && left) {
1780                 if(put_user('\n', s))
1781                         return -EFAULT;
1782                 left--, s++;
1783         }
1784         if (write) {
1785                 while (left) {
1786                         char c;
1787                         if (get_user(c, s++))
1788                                 return -EFAULT;
1789                         if (!isspace(c))
1790                                 break;
1791                         left--;
1792                 }
1793         }
1794         if (write && first)
1795                 return -EINVAL;
1796         *lenp -= left;
1797         *ppos += *lenp;
1798         return 0;
1799 #undef TMPBUFLEN
1800 }
1801
1802 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1803                   void __user *buffer, size_t *lenp, loff_t *ppos,
1804                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1805                               int write, void *data),
1806                   void *data)
1807 {
1808         return __do_proc_dointvec(table->data, table, write, filp,
1809                         buffer, lenp, ppos, conv, data);
1810 }
1811
1812 /**
1813  * proc_dointvec - read a vector of integers
1814  * @table: the sysctl table
1815  * @write: %TRUE if this is a write to the sysctl file
1816  * @filp: the file structure
1817  * @buffer: the user buffer
1818  * @lenp: the size of the user buffer
1819  * @ppos: file position
1820  *
1821  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1822  * values from/to the user buffer, treated as an ASCII string.
1823  *
1824  * Returns 0 on success.
1825  */
1826 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1827                      void __user *buffer, size_t *lenp, loff_t *ppos)
1828 {
1829     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1830                             NULL,NULL);
1831 }
1832
1833 #define OP_SET  0
1834 #define OP_AND  1
1835 #define OP_OR   2
1836
1837 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1838                                       int *valp,
1839                                       int write, void *data)
1840 {
1841         int op = *(int *)data;
1842         if (write) {
1843                 int val = *negp ? -*lvalp : *lvalp;
1844                 switch(op) {
1845                 case OP_SET:    *valp = val; break;
1846                 case OP_AND:    *valp &= val; break;
1847                 case OP_OR:     *valp |= val; break;
1848                 }
1849         } else {
1850                 int val = *valp;
1851                 if (val < 0) {
1852                         *negp = -1;
1853                         *lvalp = (unsigned long)-val;
1854                 } else {
1855                         *negp = 0;
1856                         *lvalp = (unsigned long)val;
1857                 }
1858         }
1859         return 0;
1860 }
1861
1862 /*
1863  *      init may raise the set.
1864  */
1865
1866 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1867                         void __user *buffer, size_t *lenp, loff_t *ppos)
1868 {
1869         int op;
1870
1871         if (write && !capable(CAP_SYS_MODULE)) {
1872                 return -EPERM;
1873         }
1874
1875         op = is_init(current) ? OP_SET : OP_AND;
1876         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1877                                 do_proc_dointvec_bset_conv,&op);
1878 }
1879
1880 /*
1881  *      Taint values can only be increased
1882  */
1883 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
1884                                void __user *buffer, size_t *lenp, loff_t *ppos)
1885 {
1886         int op;
1887
1888         if (write && !capable(CAP_SYS_ADMIN))
1889                 return -EPERM;
1890
1891         op = OP_OR;
1892         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1893                                 do_proc_dointvec_bset_conv,&op);
1894 }
1895
1896 struct do_proc_dointvec_minmax_conv_param {
1897         int *min;
1898         int *max;
1899 };
1900
1901 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1902                                         int *valp,
1903                                         int write, void *data)
1904 {
1905         struct do_proc_dointvec_minmax_conv_param *param = data;
1906         if (write) {
1907                 int val = *negp ? -*lvalp : *lvalp;
1908                 if ((param->min && *param->min > val) ||
1909                     (param->max && *param->max < val))
1910                         return -EINVAL;
1911                 *valp = val;
1912         } else {
1913                 int val = *valp;
1914                 if (val < 0) {
1915                         *negp = -1;
1916                         *lvalp = (unsigned long)-val;
1917                 } else {
1918                         *negp = 0;
1919                         *lvalp = (unsigned long)val;
1920                 }
1921         }
1922         return 0;
1923 }
1924
1925 /**
1926  * proc_dointvec_minmax - read a vector of integers with min/max values
1927  * @table: the sysctl table
1928  * @write: %TRUE if this is a write to the sysctl file
1929  * @filp: the file structure
1930  * @buffer: the user buffer
1931  * @lenp: the size of the user buffer
1932  * @ppos: file position
1933  *
1934  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1935  * values from/to the user buffer, treated as an ASCII string.
1936  *
1937  * This routine will ensure the values are within the range specified by
1938  * table->extra1 (min) and table->extra2 (max).
1939  *
1940  * Returns 0 on success.
1941  */
1942 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1943                   void __user *buffer, size_t *lenp, loff_t *ppos)
1944 {
1945         struct do_proc_dointvec_minmax_conv_param param = {
1946                 .min = (int *) table->extra1,
1947                 .max = (int *) table->extra2,
1948         };
1949         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1950                                 do_proc_dointvec_minmax_conv, &param);
1951 }
1952
1953 static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
1954                                      struct file *filp,
1955                                      void __user *buffer,
1956                                      size_t *lenp, loff_t *ppos,
1957                                      unsigned long convmul,
1958                                      unsigned long convdiv)
1959 {
1960 #define TMPBUFLEN 21
1961         unsigned long *i, *min, *max, val;
1962         int vleft, first=1, neg;
1963         size_t len, left;
1964         char buf[TMPBUFLEN], *p;
1965         char __user *s = buffer;
1966
1967         if (!data || !table->maxlen || !*lenp ||
1968             (*ppos && !write)) {
1969                 *lenp = 0;
1970                 return 0;
1971         }
1972
1973         i = (unsigned long *) data;
1974         min = (unsigned long *) table->extra1;
1975         max = (unsigned long *) table->extra2;
1976         vleft = table->maxlen / sizeof(unsigned long);
1977         left = *lenp;
1978
1979         for (; left && vleft--; i++, min++, max++, first=0) {
1980                 if (write) {
1981                         while (left) {
1982                                 char c;
1983                                 if (get_user(c, s))
1984                                         return -EFAULT;
1985                                 if (!isspace(c))
1986                                         break;
1987                                 left--;
1988                                 s++;
1989                         }
1990                         if (!left)
1991                                 break;
1992                         neg = 0;
1993                         len = left;
1994                         if (len > TMPBUFLEN-1)
1995                                 len = TMPBUFLEN-1;
1996                         if (copy_from_user(buf, s, len))
1997                                 return -EFAULT;
1998                         buf[len] = 0;
1999                         p = buf;
2000                         if (*p == '-' && left > 1) {
2001                                 neg = 1;
2002                                 p++;
2003                         }
2004                         if (*p < '0' || *p > '9')
2005                                 break;
2006                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2007                         len = p-buf;
2008                         if ((len < left) && *p && !isspace(*p))
2009                                 break;
2010                         if (neg)
2011                                 val = -val;
2012                         s += len;
2013                         left -= len;
2014
2015                         if(neg)
2016                                 continue;
2017                         if ((min && val < *min) || (max && val > *max))
2018                                 continue;
2019                         *i = val;
2020                 } else {
2021                         p = buf;
2022                         if (!first)
2023                                 *p++ = '\t';
2024                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2025                         len = strlen(buf);
2026                         if (len > left)
2027                                 len = left;
2028                         if(copy_to_user(s, buf, len))
2029                                 return -EFAULT;
2030                         left -= len;
2031                         s += len;
2032                 }
2033         }
2034
2035         if (!write && !first && left) {
2036                 if(put_user('\n', s))
2037                         return -EFAULT;
2038                 left--, s++;
2039         }
2040         if (write) {
2041                 while (left) {
2042                         char c;
2043                         if (get_user(c, s++))
2044                                 return -EFAULT;
2045                         if (!isspace(c))
2046                                 break;
2047                         left--;
2048                 }
2049         }
2050         if (write && first)
2051                 return -EINVAL;
2052         *lenp -= left;
2053         *ppos += *lenp;
2054         return 0;
2055 #undef TMPBUFLEN
2056 }
2057
2058 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
2059                                      struct file *filp,
2060                                      void __user *buffer,
2061                                      size_t *lenp, loff_t *ppos,
2062                                      unsigned long convmul,
2063                                      unsigned long convdiv)
2064 {
2065         return __do_proc_doulongvec_minmax(table->data, table, write,
2066                         filp, buffer, lenp, ppos, convmul, convdiv);
2067 }
2068
2069 /**
2070  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2071  * @table: the sysctl table
2072  * @write: %TRUE if this is a write to the sysctl file
2073  * @filp: the file structure
2074  * @buffer: the user buffer
2075  * @lenp: the size of the user buffer
2076  * @ppos: file position
2077  *
2078  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2079  * values from/to the user buffer, treated as an ASCII string.
2080  *
2081  * This routine will ensure the values are within the range specified by
2082  * table->extra1 (min) and table->extra2 (max).
2083  *
2084  * Returns 0 on success.
2085  */
2086 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2087                            void __user *buffer, size_t *lenp, loff_t *ppos)
2088 {
2089     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2090 }
2091
2092 /**
2093  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2094  * @table: the sysctl table
2095  * @write: %TRUE if this is a write to the sysctl file
2096  * @filp: the file structure
2097  * @buffer: the user buffer
2098  * @lenp: the size of the user buffer
2099  * @ppos: file position
2100  *
2101  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2102  * values from/to the user buffer, treated as an ASCII string. The values
2103  * are treated as milliseconds, and converted to jiffies when they are stored.
2104  *
2105  * This routine will ensure the values are within the range specified by
2106  * table->extra1 (min) and table->extra2 (max).
2107  *
2108  * Returns 0 on success.
2109  */
2110 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2111                                       struct file *filp,
2112                                       void __user *buffer,
2113                                       size_t *lenp, loff_t *ppos)
2114 {
2115     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2116                                      lenp, ppos, HZ, 1000l);
2117 }
2118
2119
2120 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2121                                          int *valp,
2122                                          int write, void *data)
2123 {
2124         if (write) {
2125                 if (*lvalp > LONG_MAX / HZ)
2126                         return 1;
2127                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2128         } else {
2129                 int val = *valp;
2130                 unsigned long lval;
2131                 if (val < 0) {
2132                         *negp = -1;
2133                         lval = (unsigned long)-val;
2134                 } else {
2135                         *negp = 0;
2136                         lval = (unsigned long)val;
2137                 }
2138                 *lvalp = lval / HZ;
2139         }
2140         return 0;
2141 }
2142
2143 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2144                                                 int *valp,
2145                                                 int write, void *data)
2146 {
2147         if (write) {
2148                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2149                         return 1;
2150                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2151         } else {
2152                 int val = *valp;
2153                 unsigned long lval;
2154                 if (val < 0) {
2155                         *negp = -1;
2156                         lval = (unsigned long)-val;
2157                 } else {
2158                         *negp = 0;
2159                         lval = (unsigned long)val;
2160                 }
2161                 *lvalp = jiffies_to_clock_t(lval);
2162         }
2163         return 0;
2164 }
2165
2166 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2167                                             int *valp,
2168                                             int write, void *data)
2169 {
2170         if (write) {
2171                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2172         } else {
2173                 int val = *valp;
2174                 unsigned long lval;
2175                 if (val < 0) {
2176                         *negp = -1;
2177                         lval = (unsigned long)-val;
2178                 } else {
2179                         *negp = 0;
2180                         lval = (unsigned long)val;
2181                 }
2182                 *lvalp = jiffies_to_msecs(lval);
2183         }
2184         return 0;
2185 }
2186
2187 /**
2188  * proc_dointvec_jiffies - read a vector of integers as seconds
2189  * @table: the sysctl table
2190  * @write: %TRUE if this is a write to the sysctl file
2191  * @filp: the file structure
2192  * @buffer: the user buffer
2193  * @lenp: the size of the user buffer
2194  * @ppos: file position
2195  *
2196  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2197  * values from/to the user buffer, treated as an ASCII string.
2198  * The values read are assumed to be in seconds, and are converted into
2199  * jiffies.
2200  *
2201  * Returns 0 on success.
2202  */
2203 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2204                           void __user *buffer, size_t *lenp, loff_t *ppos)
2205 {
2206     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2207                             do_proc_dointvec_jiffies_conv,NULL);
2208 }
2209
2210 /**
2211  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2212  * @table: the sysctl table
2213  * @write: %TRUE if this is a write to the sysctl file
2214  * @filp: the file structure
2215  * @buffer: the user buffer
2216  * @lenp: the size of the user buffer
2217  * @ppos: pointer to the file position
2218  *
2219  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2220  * values from/to the user buffer, treated as an ASCII string.
2221  * The values read are assumed to be in 1/USER_HZ seconds, and
2222  * are converted into jiffies.
2223  *
2224  * Returns 0 on success.
2225  */
2226 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2227                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2228 {
2229     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2230                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2231 }
2232
2233 /**
2234  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2235  * @table: the sysctl table
2236  * @write: %TRUE if this is a write to the sysctl file
2237  * @filp: the file structure
2238  * @buffer: the user buffer
2239  * @lenp: the size of the user buffer
2240  * @ppos: file position
2241  * @ppos: the current position in the file
2242  *
2243  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2244  * values from/to the user buffer, treated as an ASCII string.
2245  * The values read are assumed to be in 1/1000 seconds, and
2246  * are converted into jiffies.
2247  *
2248  * Returns 0 on success.
2249  */
2250 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2251                              void __user *buffer, size_t *lenp, loff_t *ppos)
2252 {
2253         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2254                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2255 }
2256
2257 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
2258                            void __user *buffer, size_t *lenp, loff_t *ppos)
2259 {
2260         struct pid *new_pid;
2261         pid_t tmp;
2262         int r;
2263
2264         tmp = pid_nr(cad_pid);
2265
2266         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2267                                lenp, ppos, NULL, NULL);
2268         if (r || !write)
2269                 return r;
2270
2271         new_pid = find_get_pid(tmp);
2272         if (!new_pid)
2273                 return -ESRCH;
2274
2275         put_pid(xchg(&cad_pid, new_pid));
2276         return 0;
2277 }
2278
2279 #else /* CONFIG_PROC_FS */
2280
2281 int proc_dostring(ctl_table *table, int write, struct file *filp,
2282                   void __user *buffer, size_t *lenp, loff_t *ppos)
2283 {
2284         return -ENOSYS;
2285 }
2286
2287 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2288                   void __user *buffer, size_t *lenp, loff_t *ppos)
2289 {
2290         return -ENOSYS;
2291 }
2292
2293 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2294                         void __user *buffer, size_t *lenp, loff_t *ppos)
2295 {
2296         return -ENOSYS;
2297 }
2298
2299 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2300                     void __user *buffer, size_t *lenp, loff_t *ppos)
2301 {
2302         return -ENOSYS;
2303 }
2304
2305 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2306                     void __user *buffer, size_t *lenp, loff_t *ppos)
2307 {
2308         return -ENOSYS;
2309 }
2310
2311 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2312                     void __user *buffer, size_t *lenp, loff_t *ppos)
2313 {
2314         return -ENOSYS;
2315 }
2316
2317 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2318                              void __user *buffer, size_t *lenp, loff_t *ppos)
2319 {
2320         return -ENOSYS;
2321 }
2322
2323 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2324                     void __user *buffer, size_t *lenp, loff_t *ppos)
2325 {
2326         return -ENOSYS;
2327 }
2328
2329 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2330                                       struct file *filp,
2331                                       void __user *buffer,
2332                                       size_t *lenp, loff_t *ppos)
2333 {
2334     return -ENOSYS;
2335 }
2336
2337
2338 #endif /* CONFIG_PROC_FS */
2339
2340
2341 #ifdef CONFIG_SYSCTL_SYSCALL
2342 /*
2343  * General sysctl support routines
2344  */
2345
2346 /* The generic string strategy routine: */
2347 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2348                   void __user *oldval, size_t __user *oldlenp,
2349                   void __user *newval, size_t newlen)
2350 {
2351         if (!table->data || !table->maxlen)
2352                 return -ENOTDIR;
2353
2354         if (oldval && oldlenp) {
2355                 size_t bufsize;
2356                 if (get_user(bufsize, oldlenp))
2357                         return -EFAULT;
2358                 if (bufsize) {
2359                         size_t len = strlen(table->data), copied;
2360
2361                         /* This shouldn't trigger for a well-formed sysctl */
2362                         if (len > table->maxlen)
2363                                 len = table->maxlen;
2364
2365                         /* Copy up to a max of bufsize-1 bytes of the string */
2366                         copied = (len >= bufsize) ? bufsize - 1 : len;
2367
2368                         if (copy_to_user(oldval, table->data, copied) ||
2369                             put_user(0, (char __user *)(oldval + copied)))
2370                                 return -EFAULT;
2371                         if (put_user(len, oldlenp))
2372                                 return -EFAULT;
2373                 }
2374         }
2375         if (newval && newlen) {
2376                 size_t len = newlen;
2377                 if (len > table->maxlen)
2378                         len = table->maxlen;
2379                 if(copy_from_user(table->data, newval, len))
2380                         return -EFAULT;
2381                 if (len == table->maxlen)
2382                         len--;
2383                 ((char *) table->data)[len] = 0;
2384         }
2385         return 1;
2386 }
2387
2388 /*
2389  * This function makes sure that all of the integers in the vector
2390  * are between the minimum and maximum values given in the arrays
2391  * table->extra1 and table->extra2, respectively.
2392  */
2393 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2394                 void __user *oldval, size_t __user *oldlenp,
2395                 void __user *newval, size_t newlen)
2396 {
2397
2398         if (newval && newlen) {
2399                 int __user *vec = (int __user *) newval;
2400                 int *min = (int *) table->extra1;
2401                 int *max = (int *) table->extra2;
2402                 size_t length;
2403                 int i;
2404
2405                 if (newlen % sizeof(int) != 0)
2406                         return -EINVAL;
2407
2408                 if (!table->extra1 && !table->extra2)
2409                         return 0;
2410
2411                 if (newlen > table->maxlen)
2412                         newlen = table->maxlen;
2413                 length = newlen / sizeof(int);
2414
2415                 for (i = 0; i < length; i++) {
2416                         int value;
2417                         if (get_user(value, vec + i))
2418                                 return -EFAULT;
2419                         if (min && value < min[i])
2420                                 return -EINVAL;
2421                         if (max && value > max[i])
2422                                 return -EINVAL;
2423                 }
2424         }
2425         return 0;
2426 }
2427
2428 /* Strategy function to convert jiffies to seconds */
2429 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2430                 void __user *oldval, size_t __user *oldlenp,
2431                 void __user *newval, size_t newlen)
2432 {
2433         if (oldval && oldlenp) {
2434                 size_t olen;
2435
2436                 if (get_user(olen, oldlenp))
2437                         return -EFAULT;
2438                 if (olen) {
2439                         int val;
2440
2441                         if (olen < sizeof(int))
2442                                 return -EINVAL;
2443
2444                         val = *(int *)(table->data) / HZ;
2445                         if (put_user(val, (int __user *)oldval))
2446                                 return -EFAULT;
2447                         if (put_user(sizeof(int), oldlenp))
2448                                 return -EFAULT;
2449                 }
2450         }
2451         if (newval && newlen) {
2452                 int new;
2453                 if (newlen != sizeof(int))
2454                         return -EINVAL;
2455                 if (get_user(new, (int __user *)newval))
2456                         return -EFAULT;
2457                 *(int *)(table->data) = new*HZ;
2458         }
2459         return 1;
2460 }
2461
2462 /* Strategy function to convert jiffies to seconds */
2463 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2464                 void __user *oldval, size_t __user *oldlenp,
2465                 void __user *newval, size_t newlen)
2466 {
2467         if (oldval && oldlenp) {
2468                 size_t olen;
2469
2470                 if (get_user(olen, oldlenp))
2471                         return -EFAULT;
2472                 if (olen) {
2473                         int val;
2474
2475                         if (olen < sizeof(int))
2476                                 return -EINVAL;
2477
2478                         val = jiffies_to_msecs(*(int *)(table->data));
2479                         if (put_user(val, (int __user *)oldval))
2480                                 return -EFAULT;
2481                         if (put_user(sizeof(int), oldlenp))
2482                                 return -EFAULT;
2483                 }
2484         }
2485         if (newval && newlen) {
2486                 int new;
2487                 if (newlen != sizeof(int))
2488                         return -EINVAL;
2489                 if (get_user(new, (int __user *)newval))
2490                         return -EFAULT;
2491                 *(int *)(table->data) = msecs_to_jiffies(new);
2492         }
2493         return 1;
2494 }
2495
2496
2497
2498 #else /* CONFIG_SYSCTL_SYSCALL */
2499
2500
2501 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2502 {
2503         static int msg_count;
2504         struct __sysctl_args tmp;
2505         int name[CTL_MAXNAME];
2506         int i;
2507
2508         /* Read in the sysctl name for better debug message logging */
2509         if (copy_from_user(&tmp, args, sizeof(tmp)))
2510                 return -EFAULT;
2511         if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
2512                 return -ENOTDIR;
2513         for (i = 0; i < tmp.nlen; i++)
2514                 if (get_user(name[i], tmp.name + i))
2515                         return -EFAULT;
2516
2517         /* Ignore accesses to kernel.version */
2518         if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2519                 goto out;
2520
2521         if (msg_count < 5) {
2522                 msg_count++;
2523                 printk(KERN_INFO
2524                         "warning: process `%s' used the removed sysctl "
2525                         "system call with ", current->comm);
2526                 for (i = 0; i < tmp.nlen; i++)
2527                         printk("%d.", name[i]);
2528                 printk("\n");
2529         }
2530 out:
2531         return -ENOSYS;
2532 }
2533
2534 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2535                   void __user *oldval, size_t __user *oldlenp,
2536                   void __user *newval, size_t newlen)
2537 {
2538         return -ENOSYS;
2539 }
2540
2541 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2542                 void __user *oldval, size_t __user *oldlenp,
2543                 void __user *newval, size_t newlen)
2544 {
2545         return -ENOSYS;
2546 }
2547
2548 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2549                 void __user *oldval, size_t __user *oldlenp,
2550                 void __user *newval, size_t newlen)
2551 {
2552         return -ENOSYS;
2553 }
2554
2555 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2556                 void __user *oldval, size_t __user *oldlenp,
2557                 void __user *newval, size_t newlen)
2558 {
2559         return -ENOSYS;
2560 }
2561
2562 #endif /* CONFIG_SYSCTL_SYSCALL */
2563
2564 /*
2565  * No sense putting this after each symbol definition, twice,
2566  * exception granted :-)
2567  */
2568 EXPORT_SYMBOL(proc_dointvec);
2569 EXPORT_SYMBOL(proc_dointvec_jiffies);
2570 EXPORT_SYMBOL(proc_dointvec_minmax);
2571 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2572 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2573 EXPORT_SYMBOL(proc_dostring);
2574 EXPORT_SYMBOL(proc_doulongvec_minmax);
2575 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2576 EXPORT_SYMBOL(register_sysctl_table);
2577 EXPORT_SYMBOL(sysctl_intvec);
2578 EXPORT_SYMBOL(sysctl_jiffies);
2579 EXPORT_SYMBOL(sysctl_ms_jiffies);
2580 EXPORT_SYMBOL(sysctl_string);
2581 EXPORT_SYMBOL(unregister_sysctl_table);