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

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/mm.h>
  23 #include <linux/swap.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/capability.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/capability.h>
  31 #include <linux/smp_lock.h>
  32 #include <linux/fs.h>
  33 #include <linux/init.h>
  34 #include <linux/kernel.h>
  35 #include <linux/kobject.h>
  36 #include <linux/net.h>
  37 #include <linux/sysrq.h>
  38 #include <linux/highuid.h>
  39 #include <linux/writeback.h>
  40 #include <linux/hugetlb.h>
  41 #include <linux/security.h>
  42 #include <linux/initrd.h>
  43 #include <linux/times.h>
  44 #include <linux/limits.h>
  45 #include <linux/dcache.h>
  46 #include <linux/syscalls.h>
  47 #include <linux/nfs_fs.h>
  48 #include <linux/acpi.h>
  49 #include <linux/reboot.h>
  50
  51 #include <asm/uaccess.h>
  52 #include <asm/processor.h>
  53
  54 #ifdef CONFIG_X86
  55 #include <asm/nmi.h>
  56 #include <asm/stacktrace.h>
  57 #endif
  58
  59 #if defined(CONFIG_SYSCTL)
  60
  61 /* External variables not in a header file. */
  62 extern int C_A_D;
  63 extern int print_fatal_signals;
  64 extern int sysctl_overcommit_memory;
  65 extern int sysctl_overcommit_ratio;
  66 extern int sysctl_panic_on_oom;
  67 extern int max_threads;
  68 extern int core_uses_pid;
  69 extern int suid_dumpable;
  70 extern char core_pattern[];
  71 extern int pid_max;
  72 extern int min_free_kbytes;
  73 extern int printk_ratelimit_jiffies;
  74 extern int printk_ratelimit_burst;
  75 extern int pid_max_min, pid_max_max;
  76 extern int sysctl_drop_caches;
  77 extern int percpu_pagelist_fraction;
  78 extern int compat_log;
  79 extern int maps_protect;
  80 extern int sysctl_stat_interval;
  81 extern int audit_argv_kb;
  82
  83 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  84 static int maxolduid = 65535;
  85 static int minolduid;
  86 static int min_percpu_pagelist_fract = 8;
  87
  88 static int ngroups_max = NGROUPS_MAX;
  89
  90 #ifdef CONFIG_KMOD
  91 extern char modprobe_path[];
  92 #endif
  93 #ifdef CONFIG_CHR_DEV_SG
  94 extern int sg_big_buff;
  95 #endif
  96
  97 #ifdef __sparc__
  98 extern char reboot_command [];
  99 extern int stop_a_enabled;
 100 extern int scons_pwroff;
 101 #endif
 102
 103 #ifdef __hppa__
 104 extern int pwrsw_enabled;
 105 extern int unaligned_enabled;
 106 #endif
 107
 108 #ifdef CONFIG_S390
 109 #ifdef CONFIG_MATHEMU
 110 extern int sysctl_ieee_emulation_warnings;
 111 #endif
 112 extern int sysctl_userprocess_debug;
 113 extern int spin_retry;
 114 #endif
 115
 116 extern int sysctl_hz_timer;
 117
 118 #ifdef CONFIG_BSD_PROCESS_ACCT
 119 extern int acct_parm[];
 120 #endif
 121
 122 #ifdef CONFIG_IA64
 123 extern int no_unaligned_warning;
 124 #endif
 125
 126 #ifdef CONFIG_RT_MUTEXES
 127 extern int max_lock_depth;
 128 #endif
 129
 130 #ifdef CONFIG_SYSCTL_SYSCALL
 131 static int parse_table(int __user *, int, void __user *, size_t __user *,
 132                 void __user *, size_t, ctl_table *);
 133 #endif
 134
 135
 136 #ifdef CONFIG_PROC_SYSCTL
 137 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
 138                   void __user *buffer, size_t *lenp, loff_t *ppos);
 139 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
 140                                void __user *buffer, size_t *lenp, loff_t *ppos);
 141 #endif
 142
 143 static ctl_table root_table[];
 144 static struct ctl_table_header root_table_header =
 145         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 146
 147 static ctl_table kern_table[];
 148 static ctl_table vm_table[];
 149 static ctl_table fs_table[];
 150 static ctl_table debug_table[];
 151 static ctl_table dev_table[];
 152 extern ctl_table random_table[];
 153 #ifdef CONFIG_UNIX98_PTYS
 154 extern ctl_table pty_table[];
 155 #endif
 156 #ifdef CONFIG_INOTIFY_USER
 157 extern ctl_table inotify_table[];
 158 #endif
 159
 160 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 161 int sysctl_legacy_va_layout;
 162 #endif
 163
 164 extern int prove_locking;
 165 extern int lock_stat;
 166
 167 /* The default sysctl tables: */
 168
 169 static ctl_table root_table[] = {
 170         {
 171                 .ctl_name       = CTL_KERN,
 172                 .procname       = "kernel",
 173                 .mode           = 0555,
 174                 .child          = kern_table,
 175         },
 176         {
 177                 .ctl_name       = CTL_VM,
 178                 .procname       = "vm",
 179                 .mode           = 0555,
 180                 .child          = vm_table,
 181         },
 182 #ifdef CONFIG_NET
 183         {
 184                 .ctl_name       = CTL_NET,
 185                 .procname       = "net",
 186                 .mode           = 0555,
 187                 .child          = net_table,
 188         },
 189 #endif
 190         {
 191                 .ctl_name       = CTL_FS,
 192                 .procname       = "fs",
 193                 .mode           = 0555,
 194                 .child          = fs_table,
 195         },
 196         {
 197                 .ctl_name       = CTL_DEBUG,
 198                 .procname       = "debug",
 199                 .mode           = 0555,
 200                 .child          = debug_table,
 201         },
 202         {
 203                 .ctl_name       = CTL_DEV,
 204                 .procname       = "dev",
 205                 .mode           = 0555,
 206                 .child          = dev_table,
 207         },
 208 /*
 209  * NOTE: do not add new entries to this table unless you have read
 210  * Documentation/sysctl/ctl_unnumbered.txt
 211  */
 212         { .ctl_name = 0 }
 213 };
 214
 215 #ifdef CONFIG_SCHED_DEBUG
 216 static unsigned long min_sched_granularity_ns = 100000;         /* 100 usecs */
 217 static unsigned long max_sched_granularity_ns = 1000000000;     /* 1 second */
 218 static unsigned long min_wakeup_granularity_ns;                 /* 0 usecs */
 219 static unsigned long max_wakeup_granularity_ns = 1000000000;    /* 1 second */
 220 #endif
 221
 222 static ctl_table kern_table[] = {
 223 #ifdef CONFIG_SCHED_DEBUG
 224         {
 225                 .ctl_name       = CTL_UNNUMBERED,
 226                 .procname       = "sched_granularity_ns",
 227                 .data           = &sysctl_sched_granularity,
 228                 .maxlen         = sizeof(unsigned int),
 229                 .mode           = 0644,
 230                 .proc_handler   = &proc_dointvec_minmax,
 231                 .strategy       = &sysctl_intvec,
 232                 .extra1         = &min_sched_granularity_ns,
 233                 .extra2         = &max_sched_granularity_ns,
 234         },
 235         {
 236                 .ctl_name       = CTL_UNNUMBERED,
 237                 .procname       = "sched_wakeup_granularity_ns",
 238                 .data           = &sysctl_sched_wakeup_granularity,
 239                 .maxlen         = sizeof(unsigned int),
 240                 .mode           = 0644,
 241                 .proc_handler   = &proc_dointvec_minmax,
 242                 .strategy       = &sysctl_intvec,
 243                 .extra1         = &min_wakeup_granularity_ns,
 244                 .extra2         = &max_wakeup_granularity_ns,
 245         },
 246         {
 247                 .ctl_name       = CTL_UNNUMBERED,
 248                 .procname       = "sched_batch_wakeup_granularity_ns",
 249                 .data           = &sysctl_sched_batch_wakeup_granularity,
 250                 .maxlen         = sizeof(unsigned int),
 251                 .mode           = 0644,
 252                 .proc_handler   = &proc_dointvec_minmax,
 253                 .strategy       = &sysctl_intvec,
 254                 .extra1         = &min_wakeup_granularity_ns,
 255                 .extra2         = &max_wakeup_granularity_ns,
 256         },
 257         {
 258                 .ctl_name       = CTL_UNNUMBERED,
 259                 .procname       = "sched_stat_granularity_ns",
 260                 .data           = &sysctl_sched_stat_granularity,
 261                 .maxlen         = sizeof(unsigned int),
 262                 .mode           = 0644,
 263                 .proc_handler   = &proc_dointvec_minmax,
 264                 .strategy       = &sysctl_intvec,
 265                 .extra1         = &min_wakeup_granularity_ns,
 266                 .extra2         = &max_wakeup_granularity_ns,
 267         },
 268         {
 269                 .ctl_name       = CTL_UNNUMBERED,
 270                 .procname       = "sched_runtime_limit_ns",
 271                 .data           = &sysctl_sched_runtime_limit,
 272                 .maxlen         = sizeof(unsigned int),
 273                 .mode           = 0644,
 274                 .proc_handler   = &proc_dointvec_minmax,
 275                 .strategy       = &sysctl_intvec,
 276                 .extra1         = &min_sched_granularity_ns,
 277                 .extra2         = &max_sched_granularity_ns,
 278         },
 279         {
 280                 .ctl_name       = CTL_UNNUMBERED,
 281                 .procname       = "sched_child_runs_first",
 282                 .data           = &sysctl_sched_child_runs_first,
 283                 .maxlen         = sizeof(unsigned int),
 284                 .mode           = 0644,
 285                 .proc_handler   = &proc_dointvec,
 286         },
 287 #ifdef CONFIG_PROVE_LOCKING
 288         {
 289                 .ctl_name       = CTL_UNNUMBERED,
 290                 .procname       = "prove_locking",
 291                 .data           = &prove_locking,
 292                 .maxlen         = sizeof(int),
 293                 .mode           = 0644,
 294                 .proc_handler   = &proc_dointvec,
 295         },
 296 #endif
 297 #ifdef CONFIG_LOCK_STAT
 298         {
 299                 .ctl_name       = CTL_UNNUMBERED,
 300                 .procname       = "lock_stat",
 301                 .data           = &lock_stat,
 302                 .maxlen         = sizeof(int),
 303                 .mode           = 0644,
 304                 .proc_handler   = &proc_dointvec,
 305         },
 306 #endif
 307         {
 308                 .ctl_name       = CTL_UNNUMBERED,
 309                 .procname       = "sched_features",
 310                 .data           = &sysctl_sched_features,
 311                 .maxlen         = sizeof(unsigned int),
 312                 .mode           = 0644,
 313                 .proc_handler   = &proc_dointvec,
 314         },
 315 #endif
 316         {
 317                 .ctl_name       = KERN_PANIC,
 318                 .procname       = "panic",
 319                 .data           = &panic_timeout,
 320                 .maxlen         = sizeof(int),
 321                 .mode           = 0644,
 322                 .proc_handler   = &proc_dointvec,
 323         },
 324         {
 325                 .ctl_name       = KERN_CORE_USES_PID,
 326                 .procname       = "core_uses_pid",
 327                 .data           = &core_uses_pid,
 328                 .maxlen         = sizeof(int),
 329                 .mode           = 0644,
 330                 .proc_handler   = &proc_dointvec,
 331         },
 332 #ifdef CONFIG_AUDITSYSCALL
 333         {
 334                 .ctl_name       = CTL_UNNUMBERED,
 335                 .procname       = "audit_argv_kb",
 336                 .data           = &audit_argv_kb,
 337                 .maxlen         = sizeof(int),
 338                 .mode           = 0644,
 339                 .proc_handler   = &proc_dointvec,
 340         },
 341 #endif
 342         {
 343                 .ctl_name       = KERN_CORE_PATTERN,
 344                 .procname       = "core_pattern",
 345                 .data           = core_pattern,
 346                 .maxlen         = CORENAME_MAX_SIZE,
 347                 .mode           = 0644,
 348                 .proc_handler   = &proc_dostring,
 349                 .strategy       = &sysctl_string,
 350         },
 351 #ifdef CONFIG_PROC_SYSCTL
 352         {
 353                 .ctl_name       = KERN_TAINTED,
 354                 .procname       = "tainted",
 355                 .data           = &tainted,
 356                 .maxlen         = sizeof(int),
 357                 .mode           = 0644,
 358                 .proc_handler   = &proc_dointvec_taint,
 359         },
 360 #endif
 361         {
 362                 .ctl_name       = KERN_CAP_BSET,
 363                 .procname       = "cap-bound",
 364                 .data           = &cap_bset,
 365                 .maxlen         = sizeof(kernel_cap_t),
 366                 .mode           = 0600,
 367                 .proc_handler   = &proc_dointvec_bset,
 368         },
 369 #ifdef CONFIG_BLK_DEV_INITRD
 370         {
 371                 .ctl_name       = KERN_REALROOTDEV,
 372                 .procname       = "real-root-dev",
 373                 .data           = &real_root_dev,
 374                 .maxlen         = sizeof(int),
 375                 .mode           = 0644,
 376                 .proc_handler   = &proc_dointvec,
 377         },
 378 #endif
 379         {
 380                 .ctl_name       = CTL_UNNUMBERED,
 381                 .procname       = "print-fatal-signals",
 382                 .data           = &print_fatal_signals,
 383                 .maxlen         = sizeof(int),
 384                 .mode           = 0644,
 385                 .proc_handler   = &proc_dointvec,
 386         },
 387 #ifdef __sparc__
 388         {
 389                 .ctl_name       = KERN_SPARC_REBOOT,
 390                 .procname       = "reboot-cmd",
 391                 .data           = reboot_command,
 392                 .maxlen         = 256,
 393                 .mode           = 0644,
 394                 .proc_handler   = &proc_dostring,
 395                 .strategy       = &sysctl_string,
 396         },
 397         {
 398                 .ctl_name       = KERN_SPARC_STOP_A,
 399                 .procname       = "stop-a",
 400                 .data           = &stop_a_enabled,
 401                 .maxlen         = sizeof (int),
 402                 .mode           = 0644,
 403                 .proc_handler   = &proc_dointvec,
 404         },
 405         {
 406                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 407                 .procname       = "scons-poweroff",
 408                 .data           = &scons_pwroff,
 409                 .maxlen         = sizeof (int),
 410                 .mode           = 0644,
 411                 .proc_handler   = &proc_dointvec,
 412         },
 413 #endif
 414 #ifdef __hppa__
 415         {
 416                 .ctl_name       = KERN_HPPA_PWRSW,
 417                 .procname       = "soft-power",
 418                 .data           = &pwrsw_enabled,
 419                 .maxlen         = sizeof (int),
 420                 .mode           = 0644,
 421                 .proc_handler   = &proc_dointvec,
 422         },
 423         {
 424                 .ctl_name       = KERN_HPPA_UNALIGNED,
 425                 .procname       = "unaligned-trap",
 426                 .data           = &unaligned_enabled,
 427                 .maxlen         = sizeof (int),
 428                 .mode           = 0644,
 429                 .proc_handler   = &proc_dointvec,
 430         },
 431 #endif
 432         {
 433                 .ctl_name       = KERN_CTLALTDEL,
 434                 .procname       = "ctrl-alt-del",
 435                 .data           = &C_A_D,
 436                 .maxlen         = sizeof(int),
 437                 .mode           = 0644,
 438                 .proc_handler   = &proc_dointvec,
 439         },
 440         {
 441                 .ctl_name       = KERN_PRINTK,
 442                 .procname       = "printk",
 443                 .data           = &console_loglevel,
 444                 .maxlen         = 4*sizeof(int),
 445                 .mode           = 0644,
 446                 .proc_handler   = &proc_dointvec,
 447         },
 448 #ifdef CONFIG_KMOD
 449         {
 450                 .ctl_name       = KERN_MODPROBE,
 451                 .procname       = "modprobe",
 452                 .data           = &modprobe_path,
 453                 .maxlen         = KMOD_PATH_LEN,
 454                 .mode           = 0644,
 455                 .proc_handler   = &proc_dostring,
 456                 .strategy       = &sysctl_string,
 457         },
 458 #endif
 459 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 460         {
 461                 .ctl_name       = KERN_HOTPLUG,
 462                 .procname       = "hotplug",
 463                 .data           = &uevent_helper,
 464                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 465                 .mode           = 0644,
 466                 .proc_handler   = &proc_dostring,
 467                 .strategy       = &sysctl_string,
 468         },
 469 #endif
 470 #ifdef CONFIG_CHR_DEV_SG
 471         {
 472                 .ctl_name       = KERN_SG_BIG_BUFF,
 473                 .procname       = "sg-big-buff",
 474                 .data           = &sg_big_buff,
 475                 .maxlen         = sizeof (int),
 476                 .mode           = 0444,
 477                 .proc_handler   = &proc_dointvec,
 478         },
 479 #endif
 480 #ifdef CONFIG_BSD_PROCESS_ACCT
 481         {
 482                 .ctl_name       = KERN_ACCT,
 483                 .procname       = "acct",
 484                 .data           = &acct_parm,
 485                 .maxlen         = 3*sizeof(int),
 486                 .mode           = 0644,
 487                 .proc_handler   = &proc_dointvec,
 488         },
 489 #endif
 490 #ifdef CONFIG_MAGIC_SYSRQ
 491         {
 492                 .ctl_name       = KERN_SYSRQ,
 493                 .procname       = "sysrq",
 494                 .data           = &__sysrq_enabled,
 495                 .maxlen         = sizeof (int),
 496                 .mode           = 0644,
 497                 .proc_handler   = &proc_dointvec,
 498         },
 499 #endif
 500 #ifdef CONFIG_PROC_SYSCTL
 501         {
 502                 .ctl_name       = KERN_CADPID,
 503                 .procname       = "cad_pid",
 504                 .data           = NULL,
 505                 .maxlen         = sizeof (int),
 506                 .mode           = 0600,
 507                 .proc_handler   = &proc_do_cad_pid,
 508         },
 509 #endif
 510         {
 511                 .ctl_name       = KERN_MAX_THREADS,
 512                 .procname       = "threads-max",
 513                 .data           = &max_threads,
 514                 .maxlen         = sizeof(int),
 515                 .mode           = 0644,
 516                 .proc_handler   = &proc_dointvec,
 517         },
 518         {
 519                 .ctl_name       = KERN_RANDOM,
 520                 .procname       = "random",
 521                 .mode           = 0555,
 522                 .child          = random_table,
 523         },
 524 #ifdef CONFIG_UNIX98_PTYS
 525         {
 526                 .ctl_name       = KERN_PTY,
 527                 .procname       = "pty",
 528                 .mode           = 0555,
 529                 .child          = pty_table,
 530         },
 531 #endif
 532         {
 533                 .ctl_name       = KERN_OVERFLOWUID,
 534                 .procname       = "overflowuid",
 535                 .data           = &overflowuid,
 536                 .maxlen         = sizeof(int),
 537                 .mode           = 0644,
 538                 .proc_handler   = &proc_dointvec_minmax,
 539                 .strategy       = &sysctl_intvec,
 540                 .extra1         = &minolduid,
 541                 .extra2         = &maxolduid,
 542         },
 543         {
 544                 .ctl_name       = KERN_OVERFLOWGID,
 545                 .procname       = "overflowgid",
 546                 .data           = &overflowgid,
 547                 .maxlen         = sizeof(int),
 548                 .mode           = 0644,
 549                 .proc_handler   = &proc_dointvec_minmax,
 550                 .strategy       = &sysctl_intvec,
 551                 .extra1         = &minolduid,
 552                 .extra2         = &maxolduid,
 553         },
 554 #ifdef CONFIG_S390
 555 #ifdef CONFIG_MATHEMU
 556         {
 557                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 558                 .procname       = "ieee_emulation_warnings",
 559                 .data           = &sysctl_ieee_emulation_warnings,
 560                 .maxlen         = sizeof(int),
 561                 .mode           = 0644,
 562                 .proc_handler   = &proc_dointvec,
 563         },
 564 #endif
 565 #ifdef CONFIG_NO_IDLE_HZ
 566         {
 567                 .ctl_name       = KERN_HZ_TIMER,
 568                 .procname       = "hz_timer",
 569                 .data           = &sysctl_hz_timer,
 570                 .maxlen         = sizeof(int),
 571                 .mode           = 0644,
 572                 .proc_handler   = &proc_dointvec,
 573         },
 574 #endif
 575         {
 576                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 577                 .procname       = "userprocess_debug",
 578                 .data           = &sysctl_userprocess_debug,
 579                 .maxlen         = sizeof(int),
 580                 .mode           = 0644,
 581                 .proc_handler   = &proc_dointvec,
 582         },
 583 #endif
 584         {
 585                 .ctl_name       = KERN_PIDMAX,
 586                 .procname       = "pid_max",
 587                 .data           = &pid_max,
 588                 .maxlen         = sizeof (int),
 589                 .mode           = 0644,
 590                 .proc_handler   = &proc_dointvec_minmax,
 591                 .strategy       = sysctl_intvec,
 592                 .extra1         = &pid_max_min,
 593                 .extra2         = &pid_max_max,
 594         },
 595         {
 596                 .ctl_name       = KERN_PANIC_ON_OOPS,
 597                 .procname       = "panic_on_oops",
 598                 .data           = &panic_on_oops,
 599                 .maxlen         = sizeof(int),
 600                 .mode           = 0644,
 601                 .proc_handler   = &proc_dointvec,
 602         },
 603         {
 604                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 605                 .procname       = "printk_ratelimit",
 606                 .data           = &printk_ratelimit_jiffies,
 607                 .maxlen         = sizeof(int),
 608                 .mode           = 0644,
 609                 .proc_handler   = &proc_dointvec_jiffies,
 610                 .strategy       = &sysctl_jiffies,
 611         },
 612         {
 613                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 614                 .procname       = "printk_ratelimit_burst",
 615                 .data           = &printk_ratelimit_burst,
 616                 .maxlen         = sizeof(int),
 617                 .mode           = 0644,
 618                 .proc_handler   = &proc_dointvec,
 619         },
 620         {
 621                 .ctl_name       = KERN_NGROUPS_MAX,
 622                 .procname       = "ngroups_max",
 623                 .data           = &ngroups_max,
 624                 .maxlen         = sizeof (int),
 625                 .mode           = 0444,
 626                 .proc_handler   = &proc_dointvec,
 627         },
 628 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 629         {
 630                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 631                 .procname       = "unknown_nmi_panic",
 632                 .data           = &unknown_nmi_panic,
 633                 .maxlen         = sizeof (int),
 634                 .mode           = 0644,
 635                 .proc_handler   = &proc_dointvec,
 636         },
 637         {
 638                 .ctl_name       = KERN_NMI_WATCHDOG,
 639                 .procname       = "nmi_watchdog",
 640                 .data           = &nmi_watchdog_enabled,
 641                 .maxlen         = sizeof (int),
 642                 .mode           = 0644,
 643                 .proc_handler   = &proc_nmi_enabled,
 644         },
 645 #endif
 646 #if defined(CONFIG_X86)
 647         {
 648                 .ctl_name       = KERN_PANIC_ON_NMI,
 649                 .procname       = "panic_on_unrecovered_nmi",
 650                 .data           = &panic_on_unrecovered_nmi,
 651                 .maxlen         = sizeof(int),
 652                 .mode           = 0644,
 653                 .proc_handler   = &proc_dointvec,
 654         },
 655         {
 656                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 657                 .procname       = "bootloader_type",
 658                 .data           = &bootloader_type,
 659                 .maxlen         = sizeof (int),
 660                 .mode           = 0444,
 661                 .proc_handler   = &proc_dointvec,
 662         },
 663         {
 664                 .ctl_name       = CTL_UNNUMBERED,
 665                 .procname       = "kstack_depth_to_print",
 666                 .data           = &kstack_depth_to_print,
 667                 .maxlen         = sizeof(int),
 668                 .mode           = 0644,
 669                 .proc_handler   = &proc_dointvec,
 670         },
 671 #endif
 672 #if defined(CONFIG_MMU)
 673         {
 674                 .ctl_name       = KERN_RANDOMIZE,
 675                 .procname       = "randomize_va_space",
 676                 .data           = &randomize_va_space,
 677                 .maxlen         = sizeof(int),
 678                 .mode           = 0644,
 679                 .proc_handler   = &proc_dointvec,
 680         },
 681 #endif
 682 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 683         {
 684                 .ctl_name       = KERN_SPIN_RETRY,
 685                 .procname       = "spin_retry",
 686                 .data           = &spin_retry,
 687                 .maxlen         = sizeof (int),
 688                 .mode           = 0644,
 689                 .proc_handler   = &proc_dointvec,
 690         },
 691 #endif
 692 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 693         {
 694                 .ctl_name       = KERN_ACPI_VIDEO_FLAGS,
 695                 .procname       = "acpi_video_flags",
 696                 .data           = &acpi_realmode_flags,
 697                 .maxlen         = sizeof (unsigned long),
 698                 .mode           = 0644,
 699                 .proc_handler   = &proc_doulongvec_minmax,
 700         },
 701 #endif
 702 #ifdef CONFIG_IA64
 703         {
 704                 .ctl_name       = KERN_IA64_UNALIGNED,
 705                 .procname       = "ignore-unaligned-usertrap",
 706                 .data           = &no_unaligned_warning,
 707                 .maxlen         = sizeof (int),
 708                 .mode           = 0644,
 709                 .proc_handler   = &proc_dointvec,
 710         },
 711 #endif
 712 #ifdef CONFIG_COMPAT
 713         {
 714                 .ctl_name       = KERN_COMPAT_LOG,
 715                 .procname       = "compat-log",
 716                 .data           = &compat_log,
 717                 .maxlen         = sizeof (int),
 718                 .mode           = 0644,
 719                 .proc_handler   = &proc_dointvec,
 720         },
 721 #endif
 722 #ifdef CONFIG_RT_MUTEXES
 723         {
 724                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 725                 .procname       = "max_lock_depth",
 726                 .data           = &max_lock_depth,
 727                 .maxlen         = sizeof(int),
 728                 .mode           = 0644,
 729                 .proc_handler   = &proc_dointvec,
 730         },
 731 #endif
 732 #ifdef CONFIG_PROC_FS
 733         {
 734                 .ctl_name       = CTL_UNNUMBERED,
 735                 .procname       = "maps_protect",
 736                 .data           = &maps_protect,
 737                 .maxlen         = sizeof(int),
 738                 .mode           = 0644,
 739                 .proc_handler   = &proc_dointvec,
 740         },
 741 #endif
 742         {
 743                 .ctl_name       = CTL_UNNUMBERED,
 744                 .procname       = "poweroff_cmd",
 745                 .data           = &poweroff_cmd,
 746                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 747                 .mode           = 0644,
 748                 .proc_handler   = &proc_dostring,
 749                 .strategy       = &sysctl_string,
 750         },
 751 /*
 752  * NOTE: do not add new entries to this table unless you have read
 753  * Documentation/sysctl/ctl_unnumbered.txt
 754  */
 755         { .ctl_name = 0 }
 756 };
 757
 758 /* Constants for minimum and maximum testing in vm_table.
 759    We use these as one-element integer vectors. */
 760 static int zero;
 761 static int two = 2;
 762 static int one_hundred = 100;
 763
 764
 765 static ctl_table vm_table[] = {
 766         {
 767                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 768                 .procname       = "overcommit_memory",
 769                 .data           = &sysctl_overcommit_memory,
 770                 .maxlen         = sizeof(sysctl_overcommit_memory),
 771                 .mode           = 0644,
 772                 .proc_handler   = &proc_dointvec,
 773         },
 774         {
 775                 .ctl_name       = VM_PANIC_ON_OOM,
 776                 .procname       = "panic_on_oom",
 777                 .data           = &sysctl_panic_on_oom,
 778                 .maxlen         = sizeof(sysctl_panic_on_oom),
 779                 .mode           = 0644,
 780                 .proc_handler   = &proc_dointvec,
 781         },
 782         {
 783                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 784                 .procname       = "overcommit_ratio",
 785                 .data           = &sysctl_overcommit_ratio,
 786                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 787                 .mode           = 0644,
 788                 .proc_handler   = &proc_dointvec,
 789         },
 790         {
 791                 .ctl_name       = VM_PAGE_CLUSTER,
 792                 .procname       = "page-cluster",
 793                 .data           = &page_cluster,
 794                 .maxlen         = sizeof(int),
 795                 .mode           = 0644,
 796                 .proc_handler   = &proc_dointvec,
 797         },
 798         {
 799                 .ctl_name       = VM_DIRTY_BACKGROUND,
 800                 .procname       = "dirty_background_ratio",
 801                 .data           = &dirty_background_ratio,
 802                 .maxlen         = sizeof(dirty_background_ratio),
 803                 .mode           = 0644,
 804                 .proc_handler   = &proc_dointvec_minmax,
 805                 .strategy       = &sysctl_intvec,
 806                 .extra1         = &zero,
 807                 .extra2         = &one_hundred,
 808         },
 809         {
 810                 .ctl_name       = VM_DIRTY_RATIO,
 811                 .procname       = "dirty_ratio",
 812                 .data           = &vm_dirty_ratio,
 813                 .maxlen         = sizeof(vm_dirty_ratio),
 814                 .mode           = 0644,
 815                 .proc_handler   = &proc_dointvec_minmax,
 816                 .strategy       = &sysctl_intvec,
 817                 .extra1         = &zero,
 818                 .extra2         = &one_hundred,
 819         },
 820         {
 821                 .ctl_name       = VM_DIRTY_WB_CS,
 822                 .procname       = "dirty_writeback_centisecs",
 823                 .data           = &dirty_writeback_interval,
 824                 .maxlen         = sizeof(dirty_writeback_interval),
 825                 .mode           = 0644,
 826                 .proc_handler   = &dirty_writeback_centisecs_handler,
 827         },
 828         {
 829                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 830                 .procname       = "dirty_expire_centisecs",
 831                 .data           = &dirty_expire_interval,
 832                 .maxlen         = sizeof(dirty_expire_interval),
 833                 .mode           = 0644,
 834                 .proc_handler   = &proc_dointvec_userhz_jiffies,
 835         },
 836         {
 837                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 838                 .procname       = "nr_pdflush_threads",
 839                 .data           = &nr_pdflush_threads,
 840                 .maxlen         = sizeof nr_pdflush_threads,
 841                 .mode           = 0444 /* read-only*/,
 842                 .proc_handler   = &proc_dointvec,
 843         },
 844         {
 845                 .ctl_name       = VM_SWAPPINESS,
 846                 .procname       = "swappiness",
 847                 .data           = &vm_swappiness,
 848                 .maxlen         = sizeof(vm_swappiness),
 849                 .mode           = 0644,
 850                 .proc_handler   = &proc_dointvec_minmax,
 851                 .strategy       = &sysctl_intvec,
 852                 .extra1         = &zero,
 853                 .extra2         = &one_hundred,
 854         },
 855 #ifdef CONFIG_HUGETLB_PAGE
 856          {
 857                 .ctl_name       = VM_HUGETLB_PAGES,
 858                 .procname       = "nr_hugepages",
 859                 .data           = &max_huge_pages,
 860                 .maxlen         = sizeof(unsigned long),
 861                 .mode           = 0644,
 862                 .proc_handler   = &hugetlb_sysctl_handler,
 863                 .extra1         = (void *)&hugetlb_zero,
 864                 .extra2         = (void *)&hugetlb_infinity,
 865          },
 866          {
 867                 .ctl_name       = VM_HUGETLB_GROUP,
 868                 .procname       = "hugetlb_shm_group",
 869                 .data           = &sysctl_hugetlb_shm_group,
 870                 .maxlen         = sizeof(gid_t),
 871                 .mode           = 0644,
 872                 .proc_handler   = &proc_dointvec,
 873          },
 874          {
 875                 .ctl_name       = CTL_UNNUMBERED,
 876                 .procname       = "hugepages_treat_as_movable",
 877                 .data           = &hugepages_treat_as_movable,
 878                 .maxlen         = sizeof(int),
 879                 .mode           = 0644,
 880                 .proc_handler   = &hugetlb_treat_movable_handler,
 881         },
 882 #endif
 883         {
 884                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 885                 .procname       = "lowmem_reserve_ratio",
 886                 .data           = &sysctl_lowmem_reserve_ratio,
 887                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 888                 .mode           = 0644,
 889                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 890                 .strategy       = &sysctl_intvec,
 891         },
 892         {
 893                 .ctl_name       = VM_DROP_PAGECACHE,
 894                 .procname       = "drop_caches",
 895                 .data           = &sysctl_drop_caches,
 896                 .maxlen         = sizeof(int),
 897                 .mode           = 0644,
 898                 .proc_handler   = drop_caches_sysctl_handler,
 899                 .strategy       = &sysctl_intvec,
 900         },
 901         {
 902                 .ctl_name       = VM_MIN_FREE_KBYTES,
 903                 .procname       = "min_free_kbytes",
 904                 .data           = &min_free_kbytes,
 905                 .maxlen         = sizeof(min_free_kbytes),
 906                 .mode           = 0644,
 907                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 908                 .strategy       = &sysctl_intvec,
 909                 .extra1         = &zero,
 910         },
 911         {
 912                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
 913                 .procname       = "percpu_pagelist_fraction",
 914                 .data           = &percpu_pagelist_fraction,
 915                 .maxlen         = sizeof(percpu_pagelist_fraction),
 916                 .mode           = 0644,
 917                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
 918                 .strategy       = &sysctl_intvec,
 919                 .extra1         = &min_percpu_pagelist_fract,
 920         },
 921 #ifdef CONFIG_MMU
 922         {
 923                 .ctl_name       = VM_MAX_MAP_COUNT,
 924                 .procname       = "max_map_count",
 925                 .data           = &sysctl_max_map_count,
 926                 .maxlen         = sizeof(sysctl_max_map_count),
 927                 .mode           = 0644,
 928                 .proc_handler   = &proc_dointvec
 929         },
 930 #endif
 931         {
 932                 .ctl_name       = VM_LAPTOP_MODE,
 933                 .procname       = "laptop_mode",
 934                 .data           = &laptop_mode,
 935                 .maxlen         = sizeof(laptop_mode),
 936                 .mode           = 0644,
 937                 .proc_handler   = &proc_dointvec_jiffies,
 938                 .strategy       = &sysctl_jiffies,
 939         },
 940         {
 941                 .ctl_name       = VM_BLOCK_DUMP,
 942                 .procname       = "block_dump",
 943                 .data           = &block_dump,
 944                 .maxlen         = sizeof(block_dump),
 945                 .mode           = 0644,
 946                 .proc_handler   = &proc_dointvec,
 947                 .strategy       = &sysctl_intvec,
 948                 .extra1         = &zero,
 949         },
 950         {
 951                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 952                 .procname       = "vfs_cache_pressure",
 953                 .data           = &sysctl_vfs_cache_pressure,
 954                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 955                 .mode           = 0644,
 956                 .proc_handler   = &proc_dointvec,
 957                 .strategy       = &sysctl_intvec,
 958                 .extra1         = &zero,
 959         },
 960 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 961         {
 962                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 963                 .procname       = "legacy_va_layout",
 964                 .data           = &sysctl_legacy_va_layout,
 965                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 966                 .mode           = 0644,
 967                 .proc_handler   = &proc_dointvec,
 968                 .strategy       = &sysctl_intvec,
 969                 .extra1         = &zero,
 970         },
 971 #endif
 972 #ifdef CONFIG_NUMA
 973         {
 974                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
 975                 .procname       = "zone_reclaim_mode",
 976                 .data           = &zone_reclaim_mode,
 977                 .maxlen         = sizeof(zone_reclaim_mode),
 978                 .mode           = 0644,
 979                 .proc_handler   = &proc_dointvec,
 980                 .strategy       = &sysctl_intvec,
 981                 .extra1         = &zero,
 982         },
 983         {
 984                 .ctl_name       = VM_MIN_UNMAPPED,
 985                 .procname       = "min_unmapped_ratio",
 986                 .data           = &sysctl_min_unmapped_ratio,
 987                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
 988                 .mode           = 0644,
 989                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
 990                 .strategy       = &sysctl_intvec,
 991                 .extra1         = &zero,
 992                 .extra2         = &one_hundred,
 993         },
 994         {
 995                 .ctl_name       = VM_MIN_SLAB,
 996                 .procname       = "min_slab_ratio",
 997                 .data           = &sysctl_min_slab_ratio,
 998                 .maxlen         = sizeof(sysctl_min_slab_ratio),
 999                 .mode           = 0644,
1000                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1001                 .strategy       = &sysctl_intvec,
1002                 .extra1         = &zero,
1003                 .extra2         = &one_hundred,
1004         },
1005 #endif
1006 #ifdef CONFIG_SMP
1007         {
1008                 .ctl_name       = CTL_UNNUMBERED,
1009                 .procname       = "stat_interval",
1010                 .data           = &sysctl_stat_interval,
1011                 .maxlen         = sizeof(sysctl_stat_interval),
1012                 .mode           = 0644,
1013                 .proc_handler   = &proc_dointvec_jiffies,
1014                 .strategy       = &sysctl_jiffies,
1015         },
1016 #endif
1017 #ifdef CONFIG_SECURITY
1018         {
1019                 .ctl_name       = CTL_UNNUMBERED,
1020                 .procname       = "mmap_min_addr",
1021                 .data           = &mmap_min_addr,
1022                 .maxlen         = sizeof(unsigned long),
1023                 .mode           = 0644,
1024                 .proc_handler   = &proc_doulongvec_minmax,
1025         },
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 #endif
1038 #if defined(CONFIG_X86_32) || \
1039    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1040         {
1041                 .ctl_name       = VM_VDSO_ENABLED,
1042                 .procname       = "vdso_enabled",
1043                 .data           = &vdso_enabled,
1044                 .maxlen         = sizeof(vdso_enabled),
1045                 .mode           = 0644,
1046                 .proc_handler   = &proc_dointvec,
1047                 .strategy       = &sysctl_intvec,
1048                 .extra1         = &zero,
1049         },
1050 #endif
1051 /*
1052  * NOTE: do not add new entries to this table unless you have read
1053  * Documentation/sysctl/ctl_unnumbered.txt
1054  */
1055         { .ctl_name = 0 }
1056 };
1057
1058 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1059 static ctl_table binfmt_misc_table[] = {
1060         { .ctl_name = 0 }
1061 };
1062 #endif
1063
1064 static ctl_table fs_table[] = {
1065         {
1066                 .ctl_name       = FS_NRINODE,
1067                 .procname       = "inode-nr",
1068                 .data           = &inodes_stat,
1069                 .maxlen         = 2*sizeof(int),
1070                 .mode           = 0444,
1071                 .proc_handler   = &proc_dointvec,
1072         },
1073         {
1074                 .ctl_name       = FS_STATINODE,
1075                 .procname       = "inode-state",
1076                 .data           = &inodes_stat,
1077                 .maxlen         = 7*sizeof(int),
1078                 .mode           = 0444,
1079                 .proc_handler   = &proc_dointvec,
1080         },
1081         {
1082                 .ctl_name       = FS_NRFILE,
1083                 .procname       = "file-nr",
1084                 .data           = &files_stat,
1085                 .maxlen         = 3*sizeof(int),
1086                 .mode           = 0444,
1087                 .proc_handler   = &proc_nr_files,
1088         },
1089         {
1090                 .ctl_name       = FS_MAXFILE,
1091                 .procname       = "file-max",
1092                 .data           = &files_stat.max_files,
1093                 .maxlen         = sizeof(int),
1094                 .mode           = 0644,
1095                 .proc_handler   = &proc_dointvec,
1096         },
1097         {
1098                 .ctl_name       = FS_DENTRY,
1099                 .procname       = "dentry-state",
1100                 .data           = &dentry_stat,
1101                 .maxlen         = 6*sizeof(int),
1102                 .mode           = 0444,
1103                 .proc_handler   = &proc_dointvec,
1104         },
1105         {
1106                 .ctl_name       = FS_OVERFLOWUID,
1107                 .procname       = "overflowuid",
1108                 .data           = &fs_overflowuid,
1109                 .maxlen         = sizeof(int),
1110                 .mode           = 0644,
1111                 .proc_handler   = &proc_dointvec_minmax,
1112                 .strategy       = &sysctl_intvec,
1113                 .extra1         = &minolduid,
1114                 .extra2         = &maxolduid,
1115         },
1116         {
1117                 .ctl_name       = FS_OVERFLOWGID,
1118                 .procname       = "overflowgid",
1119                 .data           = &fs_overflowgid,
1120                 .maxlen         = sizeof(int),
1121                 .mode           = 0644,
1122                 .proc_handler   = &proc_dointvec_minmax,
1123                 .strategy       = &sysctl_intvec,
1124                 .extra1         = &minolduid,
1125                 .extra2         = &maxolduid,
1126         },
1127         {
1128                 .ctl_name       = FS_LEASES,
1129                 .procname       = "leases-enable",
1130                 .data           = &leases_enable,
1131                 .maxlen         = sizeof(int),
1132                 .mode           = 0644,
1133                 .proc_handler   = &proc_dointvec,
1134         },
1135 #ifdef CONFIG_DNOTIFY
1136         {
1137                 .ctl_name       = FS_DIR_NOTIFY,
1138                 .procname       = "dir-notify-enable",
1139                 .data           = &dir_notify_enable,
1140                 .maxlen         = sizeof(int),
1141                 .mode           = 0644,
1142                 .proc_handler   = &proc_dointvec,
1143         },
1144 #endif
1145 #ifdef CONFIG_MMU
1146         {
1147                 .ctl_name       = FS_LEASE_TIME,
1148                 .procname       = "lease-break-time",
1149                 .data           = &lease_break_time,
1150                 .maxlen         = sizeof(int),
1151                 .mode           = 0644,
1152                 .proc_handler   = &proc_dointvec_minmax,
1153                 .strategy       = &sysctl_intvec,
1154                 .extra1         = &zero,
1155                 .extra2         = &two,
1156         },
1157         {
1158                 .ctl_name       = FS_AIO_NR,
1159                 .procname       = "aio-nr",
1160                 .data           = &aio_nr,
1161                 .maxlen         = sizeof(aio_nr),
1162                 .mode           = 0444,
1163                 .proc_handler   = &proc_doulongvec_minmax,
1164         },
1165         {
1166                 .ctl_name       = FS_AIO_MAX_NR,
1167                 .procname       = "aio-max-nr",
1168                 .data           = &aio_max_nr,
1169                 .maxlen         = sizeof(aio_max_nr),
1170                 .mode           = 0644,
1171                 .proc_handler   = &proc_doulongvec_minmax,
1172         },
1173 #ifdef CONFIG_INOTIFY_USER
1174         {
1175                 .ctl_name       = FS_INOTIFY,
1176                 .procname       = "inotify",
1177                 .mode           = 0555,
1178                 .child          = inotify_table,
1179         },
1180 #endif
1181 #endif
1182         {
1183                 .ctl_name       = KERN_SETUID_DUMPABLE,
1184                 .procname       = "suid_dumpable",
1185                 .data           = &suid_dumpable,
1186                 .maxlen         = sizeof(int),
1187                 .mode           = 0644,
1188                 .proc_handler   = &proc_dointvec,
1189         },
1190 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1191         {
1192                 .ctl_name       = CTL_UNNUMBERED,
1193                 .procname       = "binfmt_misc",
1194                 .mode           = 0555,
1195                 .child          = binfmt_misc_table,
1196         },
1197 #endif
1198 /*
1199  * NOTE: do not add new entries to this table unless you have read
1200  * Documentation/sysctl/ctl_unnumbered.txt
1201  */
1202         { .ctl_name = 0 }
1203 };
1204
1205 static ctl_table debug_table[] = {
1206 #ifdef CONFIG_X86
1207         {
1208                 .ctl_name       = CTL_UNNUMBERED,
1209                 .procname       = "exception-trace",
1210                 .data           = &show_unhandled_signals,
1211                 .maxlen         = sizeof(int),
1212                 .mode           = 0644,
1213                 .proc_handler   = proc_dointvec
1214         },
1215 #endif
1216         { .ctl_name = 0 }
1217 };
1218
1219 static ctl_table dev_table[] = {
1220         { .ctl_name = 0 }
1221 };
1222
1223 static DEFINE_SPINLOCK(sysctl_lock);
1224
1225 /* called under sysctl_lock */
1226 static int use_table(struct ctl_table_header *p)
1227 {
1228         if (unlikely(p->unregistering))
1229                 return 0;
1230         p->used++;
1231         return 1;
1232 }
1233
1234 /* called under sysctl_lock */
1235 static void unuse_table(struct ctl_table_header *p)
1236 {
1237         if (!--p->used)
1238                 if (unlikely(p->unregistering))
1239                         complete(p->unregistering);
1240 }
1241
1242 /* called under sysctl_lock, will reacquire if has to wait */
1243 static void start_unregistering(struct ctl_table_header *p)
1244 {
1245         /*
1246          * if p->used is 0, nobody will ever touch that entry again;
1247          * we'll eliminate all paths to it before dropping sysctl_lock
1248          */
1249         if (unlikely(p->used)) {
1250                 struct completion wait;
1251                 init_completion(&wait);
1252                 p->unregistering = &wait;
1253                 spin_unlock(&sysctl_lock);
1254                 wait_for_completion(&wait);
1255                 spin_lock(&sysctl_lock);
1256         }
1257         /*
1258          * do not remove from the list until nobody holds it; walking the
1259          * list in do_sysctl() relies on that.
1260          */
1261         list_del_init(&p->ctl_entry);
1262 }
1263
1264 void sysctl_head_finish(struct ctl_table_header *head)
1265 {
1266         if (!head)
1267                 return;
1268         spin_lock(&sysctl_lock);
1269         unuse_table(head);
1270         spin_unlock(&sysctl_lock);
1271 }
1272
1273 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1274 {
1275         struct ctl_table_header *head;
1276         struct list_head *tmp;
1277         spin_lock(&sysctl_lock);
1278         if (prev) {
1279                 tmp = &prev->ctl_entry;
1280                 unuse_table(prev);
1281                 goto next;
1282         }
1283         tmp = &root_table_header.ctl_entry;
1284         for (;;) {
1285                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1286
1287                 if (!use_table(head))
1288                         goto next;
1289                 spin_unlock(&sysctl_lock);
1290                 return head;
1291         next:
1292                 tmp = tmp->next;
1293                 if (tmp == &root_table_header.ctl_entry)
1294                         break;
1295         }
1296         spin_unlock(&sysctl_lock);
1297         return NULL;
1298 }
1299
1300 #ifdef CONFIG_SYSCTL_SYSCALL
1301 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1302                void __user *newval, size_t newlen)
1303 {
1304         struct ctl_table_header *head;
1305         int error = -ENOTDIR;
1306
1307         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1308                 return -ENOTDIR;
1309         if (oldval) {
1310                 int old_len;
1311                 if (!oldlenp || get_user(old_len, oldlenp))
1312                         return -EFAULT;
1313         }
1314
1315         for (head = sysctl_head_next(NULL); head;
1316                         head = sysctl_head_next(head)) {
1317                 error = parse_table(name, nlen, oldval, oldlenp,
1318                                         newval, newlen, head->ctl_table);
1319                 if (error != -ENOTDIR) {
1320                         sysctl_head_finish(head);
1321                         break;
1322                 }
1323         }
1324         return error;
1325 }
1326
1327 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1328 {
1329         struct __sysctl_args tmp;
1330         int error;
1331
1332         if (copy_from_user(&tmp, args, sizeof(tmp)))
1333                 return -EFAULT;
1334
1335         lock_kernel();
1336         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1337                           tmp.newval, tmp.newlen);
1338         unlock_kernel();
1339         return error;
1340 }
1341 #endif /* CONFIG_SYSCTL_SYSCALL */
1342
1343 /*
1344  * sysctl_perm does NOT grant the superuser all rights automatically, because
1345  * some sysctl variables are readonly even to root.
1346  */
1347
1348 static int test_perm(int mode, int op)
1349 {
1350         if (!current->euid)
1351                 mode >>= 6;
1352         else if (in_egroup_p(0))
1353                 mode >>= 3;
1354         if ((mode & op & 0007) == op)
1355                 return 0;
1356         return -EACCES;
1357 }
1358
1359 int sysctl_perm(ctl_table *table, int op)
1360 {
1361         int error;
1362         error = security_sysctl(table, op);
1363         if (error)
1364                 return error;
1365         return test_perm(table->mode, op);
1366 }
1367
1368 #ifdef CONFIG_SYSCTL_SYSCALL
1369 static int parse_table(int __user *name, int nlen,
1370                        void __user *oldval, size_t __user *oldlenp,
1371                        void __user *newval, size_t newlen,
1372                        ctl_table *table)
1373 {
1374         int n;
1375 repeat:
1376         if (!nlen)
1377                 return -ENOTDIR;
1378         if (get_user(n, name))
1379                 return -EFAULT;
1380         for ( ; table->ctl_name || table->procname; table++) {
1381                 if (!table->ctl_name)
1382                         continue;
1383                 if (n == table->ctl_name) {
1384                         int error;
1385                         if (table->child) {
1386                                 if (sysctl_perm(table, 001))
1387                                         return -EPERM;
1388                                 name++;
1389                                 nlen--;
1390                                 table = table->child;
1391                                 goto repeat;
1392                         }
1393                         error = do_sysctl_strategy(table, name, nlen,
1394                                                    oldval, oldlenp,
1395                                                    newval, newlen);
1396                         return error;
1397                 }
1398         }
1399         return -ENOTDIR;
1400 }
1401
1402 /* Perform the actual read/write of a sysctl table entry. */
1403 int do_sysctl_strategy (ctl_table *table,
1404                         int __user *name, int nlen,
1405                         void __user *oldval, size_t __user *oldlenp,
1406                         void __user *newval, size_t newlen)
1407 {
1408         int op = 0, rc;
1409         size_t len;
1410
1411         if (oldval)
1412                 op |= 004;
1413         if (newval)
1414                 op |= 002;
1415         if (sysctl_perm(table, op))
1416                 return -EPERM;
1417
1418         if (table->strategy) {
1419                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1420                                      newval, newlen);
1421                 if (rc < 0)
1422                         return rc;
1423                 if (rc > 0)
1424                         return 0;
1425         }
1426
1427         /* If there is no strategy routine, or if the strategy returns
1428          * zero, proceed with automatic r/w */
1429         if (table->data && table->maxlen) {
1430                 if (oldval && oldlenp) {
1431                         if (get_user(len, oldlenp))
1432                                 return -EFAULT;
1433                         if (len) {
1434                                 if (len > table->maxlen)
1435                                         len = table->maxlen;
1436                                 if(copy_to_user(oldval, table->data, len))
1437                                         return -EFAULT;
1438                                 if(put_user(len, oldlenp))
1439                                         return -EFAULT;
1440                         }
1441                 }
1442                 if (newval && newlen) {
1443                         len = newlen;
1444                         if (len > table->maxlen)
1445                                 len = table->maxlen;
1446                         if(copy_from_user(table->data, newval, len))
1447                                 return -EFAULT;
1448                 }
1449         }
1450         return 0;
1451 }
1452 #endif /* CONFIG_SYSCTL_SYSCALL */
1453
1454 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1455 {
1456         for (; table->ctl_name || table->procname; table++) {
1457                 table->parent = parent;
1458                 if (table->child)
1459                         sysctl_set_parent(table, table->child);
1460         }
1461 }
1462
1463 static __init int sysctl_init(void)
1464 {
1465         sysctl_set_parent(NULL, root_table);
1466         return 0;
1467 }
1468
1469 core_initcall(sysctl_init);
1470
1471 /**
1472  * register_sysctl_table - register a sysctl hierarchy
1473  * @table: the top-level table structure
1474  *
1475  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1476  * array. An entry with a ctl_name of 0 terminates the table.
1477  *
1478  * The members of the &ctl_table structure are used as follows:
1479  *
1480  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1481  *            must be unique within that level of sysctl
1482  *
1483  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1484  *            enter a sysctl file
1485  *
1486  * data - a pointer to data for use by proc_handler
1487  *
1488  * maxlen - the maximum size in bytes of the data
1489  *
1490  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1491  *
1492  * child - a pointer to the child sysctl table if this entry is a directory, or
1493  *         %NULL.
1494  *
1495  * proc_handler - the text handler routine (described below)
1496  *
1497  * strategy - the strategy routine (described below)
1498  *
1499  * de - for internal use by the sysctl routines
1500  *
1501  * extra1, extra2 - extra pointers usable by the proc handler routines
1502  *
1503  * Leaf nodes in the sysctl tree will be represented by a single file
1504  * under /proc; non-leaf nodes will be represented by directories.
1505  *
1506  * sysctl(2) can automatically manage read and write requests through
1507  * the sysctl table.  The data and maxlen fields of the ctl_table
1508  * struct enable minimal validation of the values being written to be
1509  * performed, and the mode field allows minimal authentication.
1510  *
1511  * More sophisticated management can be enabled by the provision of a
1512  * strategy routine with the table entry.  This will be called before
1513  * any automatic read or write of the data is performed.
1514  *
1515  * The strategy routine may return
1516  *
1517  * < 0 - Error occurred (error is passed to user process)
1518  *
1519  * 0   - OK - proceed with automatic read or write.
1520  *
1521  * > 0 - OK - read or write has been done by the strategy routine, so
1522  *       return immediately.
1523  *
1524  * There must be a proc_handler routine for any terminal nodes
1525  * mirrored under /proc/sys (non-terminals are handled by a built-in
1526  * directory handler).  Several default handlers are available to
1527  * cover common cases -
1528  *
1529  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1530  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1531  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1532  *
1533  * It is the handler's job to read the input buffer from user memory
1534  * and process it. The handler should return 0 on success.
1535  *
1536  * This routine returns %NULL on a failure to register, and a pointer
1537  * to the table header on success.
1538  */
1539 struct ctl_table_header *register_sysctl_table(ctl_table * table)
1540 {
1541         struct ctl_table_header *tmp;
1542         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1543         if (!tmp)
1544                 return NULL;
1545         tmp->ctl_table = table;
1546         INIT_LIST_HEAD(&tmp->ctl_entry);
1547         tmp->used = 0;
1548         tmp->unregistering = NULL;
1549         sysctl_set_parent(NULL, table);
1550         spin_lock(&sysctl_lock);
1551         list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1552         spin_unlock(&sysctl_lock);
1553         return tmp;
1554 }
1555
1556 /**
1557  * unregister_sysctl_table - unregister a sysctl table hierarchy
1558  * @header: the header returned from register_sysctl_table
1559  *
1560  * Unregisters the sysctl table and all children. proc entries may not
1561  * actually be removed until they are no longer used by anyone.
1562  */
1563 void unregister_sysctl_table(struct ctl_table_header * header)
1564 {
1565         might_sleep();
1566         spin_lock(&sysctl_lock);
1567         start_unregistering(header);
1568         spin_unlock(&sysctl_lock);
1569         kfree(header);
1570 }
1571
1572 #else /* !CONFIG_SYSCTL */
1573 struct ctl_table_header *register_sysctl_table(ctl_table * table)
1574 {
1575         return NULL;
1576 }
1577
1578 void unregister_sysctl_table(struct ctl_table_header * table)
1579 {
1580 }
1581
1582 #endif /* CONFIG_SYSCTL */
1583
1584 /*
1585  * /proc/sys support
1586  */
1587
1588 #ifdef CONFIG_PROC_SYSCTL
1589
1590 static int _proc_do_string(void* data, int maxlen, int write,
1591                            struct file *filp, void __user *buffer,
1592                            size_t *lenp, loff_t *ppos)
1593 {
1594         size_t len;
1595         char __user *p;
1596         char c;
1597
1598         if (!data || !maxlen || !*lenp) {
1599                 *lenp = 0;
1600                 return 0;
1601         }
1602
1603         if (write) {
1604                 len = 0;
1605                 p = buffer;
1606                 while (len < *lenp) {
1607                         if (get_user(c, p++))
1608                                 return -EFAULT;
1609                         if (c == 0 || c == '\n')
1610                                 break;
1611                         len++;
1612                 }
1613                 if (len >= maxlen)
1614                         len = maxlen-1;
1615                 if(copy_from_user(data, buffer, len))
1616                         return -EFAULT;
1617                 ((char *) data)[len] = 0;
1618                 *ppos += *lenp;
1619         } else {
1620                 len = strlen(data);
1621                 if (len > maxlen)
1622                         len = maxlen;
1623
1624                 if (*ppos > len) {
1625                         *lenp = 0;
1626                         return 0;
1627                 }
1628
1629                 data += *ppos;
1630                 len  -= *ppos;
1631
1632                 if (len > *lenp)
1633                         len = *lenp;
1634                 if (len)
1635                         if(copy_to_user(buffer, data, len))
1636                                 return -EFAULT;
1637                 if (len < *lenp) {
1638                         if(put_user('\n', ((char __user *) buffer) + len))
1639                                 return -EFAULT;
1640                         len++;
1641                 }
1642                 *lenp = len;
1643                 *ppos += len;
1644         }
1645         return 0;
1646 }
1647
1648 /**
1649  * proc_dostring - read a string sysctl
1650  * @table: the sysctl table
1651  * @write: %TRUE if this is a write to the sysctl file
1652  * @filp: the file structure
1653  * @buffer: the user buffer
1654  * @lenp: the size of the user buffer
1655  * @ppos: file position
1656  *
1657  * Reads/writes a string from/to the user buffer. If the kernel
1658  * buffer provided is not large enough to hold the string, the
1659  * string is truncated. The copied string is %NULL-terminated.
1660  * If the string is being read by the user process, it is copied
1661  * and a newline '\n' is added. It is truncated if the buffer is
1662  * not large enough.
1663  *
1664  * Returns 0 on success.
1665  */
1666 int proc_dostring(ctl_table *table, int write, struct file *filp,
1667                   void __user *buffer, size_t *lenp, loff_t *ppos)
1668 {
1669         return _proc_do_string(table->data, table->maxlen, write, filp,
1670                                buffer, lenp, ppos);
1671 }
1672
1673
1674 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1675                                  int *valp,
1676                                  int write, void *data)
1677 {
1678         if (write) {
1679                 *valp = *negp ? -*lvalp : *lvalp;
1680         } else {
1681                 int val = *valp;
1682                 if (val < 0) {
1683                         *negp = -1;
1684                         *lvalp = (unsigned long)-val;
1685                 } else {
1686                         *negp = 0;
1687                         *lvalp = (unsigned long)val;
1688                 }
1689         }
1690         return 0;
1691 }
1692
1693 static int __do_proc_dointvec(void *tbl_data, ctl_table *table,
1694                   int write, struct file *filp, void __user *buffer,
1695                   size_t *lenp, loff_t *ppos,
1696                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1697                               int write, void *data),
1698                   void *data)
1699 {
1700 #define TMPBUFLEN 21
1701         int *i, vleft, first=1, neg, val;
1702         unsigned long lval;
1703         size_t left, len;
1704
1705         char buf[TMPBUFLEN], *p;
1706         char __user *s = buffer;
1707
1708         if (!tbl_data || !table->maxlen || !*lenp ||
1709             (*ppos && !write)) {
1710                 *lenp = 0;
1711                 return 0;
1712         }
1713
1714         i = (int *) tbl_data;
1715         vleft = table->maxlen / sizeof(*i);
1716         left = *lenp;
1717
1718         if (!conv)
1719                 conv = do_proc_dointvec_conv;
1720
1721         for (; left && vleft--; i++, first=0) {
1722                 if (write) {
1723                         while (left) {
1724                                 char c;
1725                                 if (get_user(c, s))
1726                                         return -EFAULT;
1727                                 if (!isspace(c))
1728                                         break;
1729                                 left--;
1730                                 s++;
1731                         }
1732                         if (!left)
1733                                 break;
1734                         neg = 0;
1735                         len = left;
1736                         if (len > sizeof(buf) - 1)
1737                                 len = sizeof(buf) - 1;
1738                         if (copy_from_user(buf, s, len))
1739                                 return -EFAULT;
1740                         buf[len] = 0;
1741                         p = buf;
1742                         if (*p == '-' && left > 1) {
1743                                 neg = 1;
1744                                 p++;
1745                         }
1746                         if (*p < '0' || *p > '9')
1747                                 break;
1748
1749                         lval = simple_strtoul(p, &p, 0);
1750
1751                         len = p-buf;
1752                         if ((len < left) && *p && !isspace(*p))
1753                                 break;
1754                         if (neg)
1755                                 val = -val;
1756                         s += len;
1757                         left -= len;
1758
1759                         if (conv(&neg, &lval, i, 1, data))
1760                                 break;
1761                 } else {
1762                         p = buf;
1763                         if (!first)
1764                                 *p++ = '\t';
1765
1766                         if (conv(&neg, &lval, i, 0, data))
1767                                 break;
1768
1769                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1770                         len = strlen(buf);
1771                         if (len > left)
1772                                 len = left;
1773                         if(copy_to_user(s, buf, len))
1774                                 return -EFAULT;
1775                         left -= len;
1776                         s += len;
1777                 }
1778         }
1779
1780         if (!write && !first && left) {
1781                 if(put_user('\n', s))
1782                         return -EFAULT;
1783                 left--, s++;
1784         }
1785         if (write) {
1786                 while (left) {
1787                         char c;
1788                         if (get_user(c, s++))
1789                                 return -EFAULT;
1790                         if (!isspace(c))
1791                                 break;
1792                         left--;
1793                 }
1794         }
1795         if (write && first)
1796                 return -EINVAL;
1797         *lenp -= left;
1798         *ppos += *lenp;
1799         return 0;
1800 #undef TMPBUFLEN
1801 }
1802
1803 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1804                   void __user *buffer, size_t *lenp, loff_t *ppos,
1805                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1806                               int write, void *data),
1807                   void *data)
1808 {
1809         return __do_proc_dointvec(table->data, table, write, filp,
1810                         buffer, lenp, ppos, conv, data);
1811 }
1812
1813 /**
1814  * proc_dointvec - read a vector of integers
1815  * @table: the sysctl table
1816  * @write: %TRUE if this is a write to the sysctl file
1817  * @filp: the file structure
1818  * @buffer: the user buffer
1819  * @lenp: the size of the user buffer
1820  * @ppos: file position
1821  *
1822  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1823  * values from/to the user buffer, treated as an ASCII string.
1824  *
1825  * Returns 0 on success.
1826  */
1827 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1828                      void __user *buffer, size_t *lenp, loff_t *ppos)
1829 {
1830     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1831                             NULL,NULL);
1832 }
1833
1834 #define OP_SET  0
1835 #define OP_AND  1
1836 #define OP_OR   2
1837
1838 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1839                                       int *valp,
1840                                       int write, void *data)
1841 {
1842         int op = *(int *)data;
1843         if (write) {
1844                 int val = *negp ? -*lvalp : *lvalp;
1845                 switch(op) {
1846                 case OP_SET:    *valp = val; break;
1847                 case OP_AND:    *valp &= val; break;
1848                 case OP_OR:     *valp |= val; break;
1849                 }
1850         } else {
1851                 int val = *valp;
1852                 if (val < 0) {
1853                         *negp = -1;
1854                         *lvalp = (unsigned long)-val;
1855                 } else {
1856                         *negp = 0;
1857                         *lvalp = (unsigned long)val;
1858                 }
1859         }
1860         return 0;
1861 }
1862
1863 /*
1864  *      init may raise the set.
1865  */
1866
1867 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1868                         void __user *buffer, size_t *lenp, loff_t *ppos)
1869 {
1870         int op;
1871
1872         if (write && !capable(CAP_SYS_MODULE)) {
1873                 return -EPERM;
1874         }
1875
1876         op = is_init(current) ? OP_SET : OP_AND;
1877         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1878                                 do_proc_dointvec_bset_conv,&op);
1879 }
1880
1881 /*
1882  *      Taint values can only be increased
1883  */
1884 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
1885                                void __user *buffer, size_t *lenp, loff_t *ppos)
1886 {
1887         int op;
1888
1889         if (write && !capable(CAP_SYS_ADMIN))
1890                 return -EPERM;
1891
1892         op = OP_OR;
1893         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1894                                 do_proc_dointvec_bset_conv,&op);
1895 }
1896
1897 struct do_proc_dointvec_minmax_conv_param {
1898         int *min;
1899         int *max;
1900 };
1901
1902 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1903                                         int *valp,
1904                                         int write, void *data)
1905 {
1906         struct do_proc_dointvec_minmax_conv_param *param = data;
1907         if (write) {
1908                 int val = *negp ? -*lvalp : *lvalp;
1909                 if ((param->min && *param->min > val) ||
1910                     (param->max && *param->max < val))
1911                         return -EINVAL;
1912                 *valp = val;
1913         } else {
1914                 int val = *valp;
1915                 if (val < 0) {
1916                         *negp = -1;
1917                         *lvalp = (unsigned long)-val;
1918                 } else {
1919                         *negp = 0;
1920                         *lvalp = (unsigned long)val;
1921                 }
1922         }
1923         return 0;
1924 }
1925
1926 /**
1927  * proc_dointvec_minmax - read a vector of integers with min/max values
1928  * @table: the sysctl table
1929  * @write: %TRUE if this is a write to the sysctl file
1930  * @filp: the file structure
1931  * @buffer: the user buffer
1932  * @lenp: the size of the user buffer
1933  * @ppos: file position
1934  *
1935  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1936  * values from/to the user buffer, treated as an ASCII string.
1937  *
1938  * This routine will ensure the values are within the range specified by
1939  * table->extra1 (min) and table->extra2 (max).
1940  *
1941  * Returns 0 on success.
1942  */
1943 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1944                   void __user *buffer, size_t *lenp, loff_t *ppos)
1945 {
1946         struct do_proc_dointvec_minmax_conv_param param = {
1947                 .min = (int *) table->extra1,
1948                 .max = (int *) table->extra2,
1949         };
1950         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1951                                 do_proc_dointvec_minmax_conv, &param);
1952 }
1953
1954 static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
1955                                      struct file *filp,
1956                                      void __user *buffer,
1957                                      size_t *lenp, loff_t *ppos,
1958                                      unsigned long convmul,
1959                                      unsigned long convdiv)
1960 {
1961 #define TMPBUFLEN 21
1962         unsigned long *i, *min, *max, val;
1963         int vleft, first=1, neg;
1964         size_t len, left;
1965         char buf[TMPBUFLEN], *p;
1966         char __user *s = buffer;
1967
1968         if (!data || !table->maxlen || !*lenp ||
1969             (*ppos && !write)) {
1970                 *lenp = 0;
1971                 return 0;
1972         }
1973
1974         i = (unsigned long *) data;
1975         min = (unsigned long *) table->extra1;
1976         max = (unsigned long *) table->extra2;
1977         vleft = table->maxlen / sizeof(unsigned long);
1978         left = *lenp;
1979
1980         for (; left && vleft--; i++, min++, max++, first=0) {
1981                 if (write) {
1982                         while (left) {
1983                                 char c;
1984                                 if (get_user(c, s))
1985                                         return -EFAULT;
1986                                 if (!isspace(c))
1987                                         break;
1988                                 left--;
1989                                 s++;
1990                         }
1991                         if (!left)
1992                                 break;
1993                         neg = 0;
1994                         len = left;
1995                         if (len > TMPBUFLEN-1)
1996                                 len = TMPBUFLEN-1;
1997                         if (copy_from_user(buf, s, len))
1998                                 return -EFAULT;
1999                         buf[len] = 0;
2000                         p = buf;
2001                         if (*p == '-' && left > 1) {
2002                                 neg = 1;
2003                                 p++;
2004                         }
2005                         if (*p < '0' || *p > '9')
2006                                 break;
2007                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2008                         len = p-buf;
2009                         if ((len < left) && *p && !isspace(*p))
2010                                 break;
2011                         if (neg)
2012                                 val = -val;
2013                         s += len;
2014                         left -= len;
2015
2016                         if(neg)
2017                                 continue;
2018                         if ((min && val < *min) || (max && val > *max))
2019                                 continue;
2020                         *i = val;
2021                 } else {
2022                         p = buf;
2023                         if (!first)
2024                                 *p++ = '\t';
2025                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2026                         len = strlen(buf);
2027                         if (len > left)
2028                                 len = left;
2029                         if(copy_to_user(s, buf, len))
2030                                 return -EFAULT;
2031                         left -= len;
2032                         s += len;
2033                 }
2034         }
2035
2036         if (!write && !first && left) {
2037                 if(put_user('\n', s))
2038                         return -EFAULT;
2039                 left--, s++;
2040         }
2041         if (write) {
2042                 while (left) {
2043                         char c;
2044                         if (get_user(c, s++))
2045                                 return -EFAULT;
2046                         if (!isspace(c))
2047                                 break;
2048                         left--;
2049                 }
2050         }
2051         if (write && first)
2052                 return -EINVAL;
2053         *lenp -= left;
2054         *ppos += *lenp;
2055         return 0;
2056 #undef TMPBUFLEN
2057 }
2058
2059 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
2060                                      struct file *filp,
2061                                      void __user *buffer,
2062                                      size_t *lenp, loff_t *ppos,
2063                                      unsigned long convmul,
2064                                      unsigned long convdiv)
2065 {
2066         return __do_proc_doulongvec_minmax(table->data, table, write,
2067                         filp, buffer, lenp, ppos, convmul, convdiv);
2068 }
2069
2070 /**
2071  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2072  * @table: the sysctl table
2073  * @write: %TRUE if this is a write to the sysctl file
2074  * @filp: the file structure
2075  * @buffer: the user buffer
2076  * @lenp: the size of the user buffer
2077  * @ppos: file position
2078  *
2079  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2080  * values from/to the user buffer, treated as an ASCII string.
2081  *
2082  * This routine will ensure the values are within the range specified by
2083  * table->extra1 (min) and table->extra2 (max).
2084  *
2085  * Returns 0 on success.
2086  */
2087 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2088                            void __user *buffer, size_t *lenp, loff_t *ppos)
2089 {
2090     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2091 }
2092
2093 /**
2094  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2095  * @table: the sysctl table
2096  * @write: %TRUE if this is a write to the sysctl file
2097  * @filp: the file structure
2098  * @buffer: the user buffer
2099  * @lenp: the size of the user buffer
2100  * @ppos: file position
2101  *
2102  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2103  * values from/to the user buffer, treated as an ASCII string. The values
2104  * are treated as milliseconds, and converted to jiffies when they are stored.
2105  *
2106  * This routine will ensure the values are within the range specified by
2107  * table->extra1 (min) and table->extra2 (max).
2108  *
2109  * Returns 0 on success.
2110  */
2111 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2112                                       struct file *filp,
2113                                       void __user *buffer,
2114                                       size_t *lenp, loff_t *ppos)
2115 {
2116     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2117                                      lenp, ppos, HZ, 1000l);
2118 }
2119
2120
2121 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2122                                          int *valp,
2123                                          int write, void *data)
2124 {
2125         if (write) {
2126                 if (*lvalp > LONG_MAX / HZ)
2127                         return 1;
2128                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2129         } else {
2130                 int val = *valp;
2131                 unsigned long lval;
2132                 if (val < 0) {
2133                         *negp = -1;
2134                         lval = (unsigned long)-val;
2135                 } else {
2136                         *negp = 0;
2137                         lval = (unsigned long)val;
2138                 }
2139                 *lvalp = lval / HZ;
2140         }
2141         return 0;
2142 }
2143
2144 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2145                                                 int *valp,
2146                                                 int write, void *data)
2147 {
2148         if (write) {
2149                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2150                         return 1;
2151                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2152         } else {
2153                 int val = *valp;
2154                 unsigned long lval;
2155                 if (val < 0) {
2156                         *negp = -1;
2157                         lval = (unsigned long)-val;
2158                 } else {
2159                         *negp = 0;
2160                         lval = (unsigned long)val;
2161                 }
2162                 *lvalp = jiffies_to_clock_t(lval);
2163         }
2164         return 0;
2165 }
2166
2167 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2168                                             int *valp,
2169                                             int write, void *data)
2170 {
2171         if (write) {
2172                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2173         } else {
2174                 int val = *valp;
2175                 unsigned long lval;
2176                 if (val < 0) {
2177                         *negp = -1;
2178                         lval = (unsigned long)-val;
2179                 } else {
2180                         *negp = 0;
2181                         lval = (unsigned long)val;
2182                 }
2183                 *lvalp = jiffies_to_msecs(lval);
2184         }
2185         return 0;
2186 }
2187
2188 /**
2189  * proc_dointvec_jiffies - read a vector of integers as seconds
2190  * @table: the sysctl table
2191  * @write: %TRUE if this is a write to the sysctl file
2192  * @filp: the file structure
2193  * @buffer: the user buffer
2194  * @lenp: the size of the user buffer
2195  * @ppos: file position
2196  *
2197  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2198  * values from/to the user buffer, treated as an ASCII string.
2199  * The values read are assumed to be in seconds, and are converted into
2200  * jiffies.
2201  *
2202  * Returns 0 on success.
2203  */
2204 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2205                           void __user *buffer, size_t *lenp, loff_t *ppos)
2206 {
2207     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2208                             do_proc_dointvec_jiffies_conv,NULL);
2209 }
2210
2211 /**
2212  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2213  * @table: the sysctl table
2214  * @write: %TRUE if this is a write to the sysctl file
2215  * @filp: the file structure
2216  * @buffer: the user buffer
2217  * @lenp: the size of the user buffer
2218  * @ppos: pointer to the file position
2219  *
2220  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2221  * values from/to the user buffer, treated as an ASCII string.
2222  * The values read are assumed to be in 1/USER_HZ seconds, and
2223  * are converted into jiffies.
2224  *
2225  * Returns 0 on success.
2226  */
2227 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2228                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2229 {
2230     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2231                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2232 }
2233
2234 /**
2235  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2236  * @table: the sysctl table
2237  * @write: %TRUE if this is a write to the sysctl file
2238  * @filp: the file structure
2239  * @buffer: the user buffer
2240  * @lenp: the size of the user buffer
2241  * @ppos: file position
2242  * @ppos: the current position in the file
2243  *
2244  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2245  * values from/to the user buffer, treated as an ASCII string.
2246  * The values read are assumed to be in 1/1000 seconds, and
2247  * are converted into jiffies.
2248  *
2249  * Returns 0 on success.
2250  */
2251 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2252                              void __user *buffer, size_t *lenp, loff_t *ppos)
2253 {
2254         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2255                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2256 }
2257
2258 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
2259                            void __user *buffer, size_t *lenp, loff_t *ppos)
2260 {
2261         struct pid *new_pid;
2262         pid_t tmp;
2263         int r;
2264
2265         tmp = pid_nr(cad_pid);
2266
2267         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2268                                lenp, ppos, NULL, NULL);
2269         if (r || !write)
2270                 return r;
2271
2272         new_pid = find_get_pid(tmp);
2273         if (!new_pid)
2274                 return -ESRCH;
2275
2276         put_pid(xchg(&cad_pid, new_pid));
2277         return 0;
2278 }
2279
2280 #else /* CONFIG_PROC_FS */
2281
2282 int proc_dostring(ctl_table *table, int write, struct file *filp,
2283                   void __user *buffer, size_t *lenp, loff_t *ppos)
2284 {
2285         return -ENOSYS;
2286 }
2287
2288 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2289                   void __user *buffer, size_t *lenp, loff_t *ppos)
2290 {
2291         return -ENOSYS;
2292 }
2293
2294 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2295                         void __user *buffer, size_t *lenp, loff_t *ppos)
2296 {
2297         return -ENOSYS;
2298 }
2299
2300 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2301                     void __user *buffer, size_t *lenp, loff_t *ppos)
2302 {
2303         return -ENOSYS;
2304 }
2305
2306 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2307                     void __user *buffer, size_t *lenp, loff_t *ppos)
2308 {
2309         return -ENOSYS;
2310 }
2311
2312 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2313                     void __user *buffer, size_t *lenp, loff_t *ppos)
2314 {
2315         return -ENOSYS;
2316 }
2317
2318 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2319                              void __user *buffer, size_t *lenp, loff_t *ppos)
2320 {
2321         return -ENOSYS;
2322 }
2323
2324 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2325                     void __user *buffer, size_t *lenp, loff_t *ppos)
2326 {
2327         return -ENOSYS;
2328 }
2329
2330 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2331                                       struct file *filp,
2332                                       void __user *buffer,
2333                                       size_t *lenp, loff_t *ppos)
2334 {
2335     return -ENOSYS;
2336 }
2337
2338
2339 #endif /* CONFIG_PROC_FS */
2340
2341
2342 #ifdef CONFIG_SYSCTL_SYSCALL
2343 /*
2344  * General sysctl support routines
2345  */
2346
2347 /* The generic string strategy routine: */
2348 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2349                   void __user *oldval, size_t __user *oldlenp,
2350                   void __user *newval, size_t newlen)
2351 {
2352         if (!table->data || !table->maxlen)
2353                 return -ENOTDIR;
2354
2355         if (oldval && oldlenp) {
2356                 size_t bufsize;
2357                 if (get_user(bufsize, oldlenp))
2358                         return -EFAULT;
2359                 if (bufsize) {
2360                         size_t len = strlen(table->data), copied;
2361
2362                         /* This shouldn't trigger for a well-formed sysctl */
2363                         if (len > table->maxlen)
2364                                 len = table->maxlen;
2365
2366                         /* Copy up to a max of bufsize-1 bytes of the string */
2367                         copied = (len >= bufsize) ? bufsize - 1 : len;
2368
2369                         if (copy_to_user(oldval, table->data, copied) ||
2370                             put_user(0, (char __user *)(oldval + copied)))
2371                                 return -EFAULT;
2372                         if (put_user(len, oldlenp))
2373                                 return -EFAULT;
2374                 }
2375         }
2376         if (newval && newlen) {
2377                 size_t len = newlen;
2378                 if (len > table->maxlen)
2379                         len = table->maxlen;
2380                 if(copy_from_user(table->data, newval, len))
2381                         return -EFAULT;
2382                 if (len == table->maxlen)
2383                         len--;
2384                 ((char *) table->data)[len] = 0;
2385         }
2386         return 1;
2387 }
2388
2389 /*
2390  * This function makes sure that all of the integers in the vector
2391  * are between the minimum and maximum values given in the arrays
2392  * table->extra1 and table->extra2, respectively.
2393  */
2394 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2395                 void __user *oldval, size_t __user *oldlenp,
2396                 void __user *newval, size_t newlen)
2397 {
2398
2399         if (newval && newlen) {
2400                 int __user *vec = (int __user *) newval;
2401                 int *min = (int *) table->extra1;
2402                 int *max = (int *) table->extra2;
2403                 size_t length;
2404                 int i;
2405
2406                 if (newlen % sizeof(int) != 0)
2407                         return -EINVAL;
2408
2409                 if (!table->extra1 && !table->extra2)
2410                         return 0;
2411
2412                 if (newlen > table->maxlen)
2413                         newlen = table->maxlen;
2414                 length = newlen / sizeof(int);
2415
2416                 for (i = 0; i < length; i++) {
2417                         int value;
2418                         if (get_user(value, vec + i))
2419                                 return -EFAULT;
2420                         if (min && value < min[i])
2421                                 return -EINVAL;
2422                         if (max && value > max[i])
2423                                 return -EINVAL;
2424                 }
2425         }
2426         return 0;
2427 }
2428
2429 /* Strategy function to convert jiffies to seconds */
2430 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2431                 void __user *oldval, size_t __user *oldlenp,
2432                 void __user *newval, size_t newlen)
2433 {
2434         if (oldval && oldlenp) {
2435                 size_t olen;
2436
2437                 if (get_user(olen, oldlenp))
2438                         return -EFAULT;
2439                 if (olen) {
2440                         int val;
2441
2442                         if (olen < sizeof(int))
2443                                 return -EINVAL;
2444
2445                         val = *(int *)(table->data) / HZ;
2446                         if (put_user(val, (int __user *)oldval))
2447                                 return -EFAULT;
2448                         if (put_user(sizeof(int), oldlenp))
2449                                 return -EFAULT;
2450                 }
2451         }
2452         if (newval && newlen) {
2453                 int new;
2454                 if (newlen != sizeof(int))
2455                         return -EINVAL;
2456                 if (get_user(new, (int __user *)newval))
2457                         return -EFAULT;
2458                 *(int *)(table->data) = new*HZ;
2459         }
2460         return 1;
2461 }
2462
2463 /* Strategy function to convert jiffies to seconds */
2464 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2465                 void __user *oldval, size_t __user *oldlenp,
2466                 void __user *newval, size_t newlen)
2467 {
2468         if (oldval && oldlenp) {
2469                 size_t olen;
2470
2471                 if (get_user(olen, oldlenp))
2472                         return -EFAULT;
2473                 if (olen) {
2474                         int val;
2475
2476                         if (olen < sizeof(int))
2477                                 return -EINVAL;
2478
2479                         val = jiffies_to_msecs(*(int *)(table->data));
2480                         if (put_user(val, (int __user *)oldval))
2481                                 return -EFAULT;
2482                         if (put_user(sizeof(int), oldlenp))
2483                                 return -EFAULT;
2484                 }
2485         }
2486         if (newval && newlen) {
2487                 int new;
2488                 if (newlen != sizeof(int))
2489                         return -EINVAL;
2490                 if (get_user(new, (int __user *)newval))
2491                         return -EFAULT;
2492                 *(int *)(table->data) = msecs_to_jiffies(new);
2493         }
2494         return 1;
2495 }
2496
2497
2498
2499 #else /* CONFIG_SYSCTL_SYSCALL */
2500
2501
2502 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2503 {
2504         static int msg_count;
2505         struct __sysctl_args tmp;
2506         int name[CTL_MAXNAME];
2507         int i;
2508
2509         /* Read in the sysctl name for better debug message logging */
2510         if (copy_from_user(&tmp, args, sizeof(tmp)))
2511                 return -EFAULT;
2512         if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
2513                 return -ENOTDIR;
2514         for (i = 0; i < tmp.nlen; i++)
2515                 if (get_user(name[i], tmp.name + i))
2516                         return -EFAULT;
2517
2518         /* Ignore accesses to kernel.version */
2519         if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2520                 goto out;
2521
2522         if (msg_count < 5) {
2523                 msg_count++;
2524                 printk(KERN_INFO
2525                         "warning: process `%s' used the removed sysctl "
2526                         "system call with ", current->comm);
2527                 for (i = 0; i < tmp.nlen; i++)
2528                         printk("%d.", name[i]);
2529                 printk("\n");
2530         }
2531 out:
2532         return -ENOSYS;
2533 }
2534
2535 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2536                   void __user *oldval, size_t __user *oldlenp,
2537                   void __user *newval, size_t newlen)
2538 {
2539         return -ENOSYS;
2540 }
2541
2542 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2543                 void __user *oldval, size_t __user *oldlenp,
2544                 void __user *newval, size_t newlen)
2545 {
2546         return -ENOSYS;
2547 }
2548
2549 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2550                 void __user *oldval, size_t __user *oldlenp,
2551                 void __user *newval, size_t newlen)
2552 {
2553         return -ENOSYS;
2554 }
2555
2556 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2557                 void __user *oldval, size_t __user *oldlenp,
2558                 void __user *newval, size_t newlen)
2559 {
2560         return -ENOSYS;
2561 }
2562
2563 #endif /* CONFIG_SYSCTL_SYSCALL */
2564
2565 /*
2566  * No sense putting this after each symbol definition, twice,
2567  * exception granted :-)
2568  */
2569 EXPORT_SYMBOL(proc_dointvec);
2570 EXPORT_SYMBOL(proc_dointvec_jiffies);
2571 EXPORT_SYMBOL(proc_dointvec_minmax);
2572 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2573 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2574 EXPORT_SYMBOL(proc_dostring);
2575 EXPORT_SYMBOL(proc_doulongvec_minmax);
2576 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2577 EXPORT_SYMBOL(register_sysctl_table);
2578 EXPORT_SYMBOL(sysctl_intvec);
2579 EXPORT_SYMBOL(sysctl_jiffies);
2580 EXPORT_SYMBOL(sysctl_ms_jiffies);
2581 EXPORT_SYMBOL(sysctl_string);
2582 EXPORT_SYMBOL(unregister_sysctl_table);