kernel/sysctl.c

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/mm.h>
  23 #include <linux/swap.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/security.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/smp_lock.h>
  31 #include <linux/fs.h>
  32 #include <linux/init.h>
  33 #include <linux/kernel.h>
  34 #include <linux/kobject.h>
  35 #include <linux/net.h>
  36 #include <linux/sysrq.h>
  37 #include <linux/highuid.h>
  38 #include <linux/writeback.h>
  39 #include <linux/hugetlb.h>
  40 #include <linux/security.h>
  41 #include <linux/initrd.h>
  42 #include <linux/times.h>
  43 #include <linux/limits.h>
  44 #include <linux/dcache.h>
  45 #include <linux/syscalls.h>
  46 #include <linux/nfs_fs.h>
  47 #include <linux/acpi.h>
  48 #include <linux/reboot.h>
  49
  50 #include <asm/uaccess.h>
  51 #include <asm/processor.h>
  52
  53 #ifdef CONFIG_X86
  54 #include <asm/nmi.h>
  55 #include <asm/stacktrace.h>
  56 #endif
  57
  58 static int deprecated_sysctl_warning(struct __sysctl_args *args);
  59
  60 #if defined(CONFIG_SYSCTL)
  61
  62 /* External variables not in a header file. */
  63 extern int C_A_D;
  64 extern int print_fatal_signals;
  65 extern int sysctl_overcommit_memory;
  66 extern int sysctl_overcommit_ratio;
  67 extern int sysctl_panic_on_oom;
  68 extern int sysctl_oom_kill_allocating_task;
  69 extern int max_threads;
  70 extern int core_uses_pid;
  71 extern int suid_dumpable;
  72 extern char core_pattern[];
  73 extern int pid_max;
  74 extern int min_free_kbytes;
  75 extern int printk_ratelimit_jiffies;
  76 extern int printk_ratelimit_burst;
  77 extern int pid_max_min, pid_max_max;
  78 extern int sysctl_drop_caches;
  79 extern int percpu_pagelist_fraction;
  80 extern int compat_log;
  81 extern int maps_protect;
  82 extern int sysctl_stat_interval;
  83 extern int audit_argv_kb;
  84
  85 /* Constants used for minimum and  maximum */
  86 #ifdef CONFIG_DETECT_SOFTLOCKUP
  87 static int one = 1;
  88 static int sixty = 60;
  89 #endif
  90
  91 #ifdef CONFIG_MMU
  92 static int two = 2;
  93 #endif
  94
  95 static int zero;
  96 static int one_hundred = 100;
  97
  98 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  99 static int maxolduid = 65535;
 100 static int minolduid;
 101 static int min_percpu_pagelist_fract = 8;
 102
 103 static int ngroups_max = NGROUPS_MAX;
 104
 105 #ifdef CONFIG_KMOD
 106 extern char modprobe_path[];
 107 #endif
 108 #ifdef CONFIG_CHR_DEV_SG
 109 extern int sg_big_buff;
 110 #endif
 111
 112 #ifdef __sparc__
 113 extern char reboot_command [];
 114 extern int stop_a_enabled;
 115 extern int scons_pwroff;
 116 #endif
 117
 118 #ifdef __hppa__
 119 extern int pwrsw_enabled;
 120 extern int unaligned_enabled;
 121 #endif
 122
 123 #ifdef CONFIG_S390
 124 #ifdef CONFIG_MATHEMU
 125 extern int sysctl_ieee_emulation_warnings;
 126 #endif
 127 extern int sysctl_userprocess_debug;
 128 extern int spin_retry;
 129 #endif
 130
 131 extern int sysctl_hz_timer;
 132
 133 #ifdef CONFIG_BSD_PROCESS_ACCT
 134 extern int acct_parm[];
 135 #endif
 136
 137 #ifdef CONFIG_IA64
 138 extern int no_unaligned_warning;
 139 #endif
 140
 141 #ifdef CONFIG_RT_MUTEXES
 142 extern int max_lock_depth;
 143 #endif
 144
 145 #ifdef CONFIG_SYSCTL_SYSCALL
 146 static int parse_table(int __user *, int, void __user *, size_t __user *,
 147                 void __user *, size_t, struct ctl_table *);
 148 #endif
 149
 150
 151 #ifdef CONFIG_PROC_SYSCTL
 152 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
 153                   void __user *buffer, size_t *lenp, loff_t *ppos);
 154 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
 155                                void __user *buffer, size_t *lenp, loff_t *ppos);
 156 #endif
 157
 158 static struct ctl_table root_table[];
 159 static struct ctl_table_header root_table_header =
 160         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 161
 162 static struct ctl_table kern_table[];
 163 static struct ctl_table vm_table[];
 164 static struct ctl_table fs_table[];
 165 static struct ctl_table debug_table[];
 166 static struct ctl_table dev_table[];
 167 extern struct ctl_table random_table[];
 168 #ifdef CONFIG_INOTIFY_USER
 169 extern struct ctl_table inotify_table[];
 170 #endif
 171
 172 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 173 int sysctl_legacy_va_layout;
 174 #endif
 175
 176 extern int prove_locking;
 177 extern int lock_stat;
 178
 179 /* The default sysctl tables: */
 180
 181 static struct ctl_table root_table[] = {
 182         {
 183                 .ctl_name       = CTL_KERN,
 184                 .procname       = "kernel",
 185                 .mode           = 0555,
 186                 .child          = kern_table,
 187         },
 188         {
 189                 .ctl_name       = CTL_VM,
 190                 .procname       = "vm",
 191                 .mode           = 0555,
 192                 .child          = vm_table,
 193         },
 194 #ifdef CONFIG_NET
 195         {
 196                 .ctl_name       = CTL_NET,
 197                 .procname       = "net",
 198                 .mode           = 0555,
 199                 .child          = net_table,
 200         },
 201 #endif
 202         {
 203                 .ctl_name       = CTL_FS,
 204                 .procname       = "fs",
 205                 .mode           = 0555,
 206                 .child          = fs_table,
 207         },
 208         {
 209                 .ctl_name       = CTL_DEBUG,
 210                 .procname       = "debug",
 211                 .mode           = 0555,
 212                 .child          = debug_table,
 213         },
 214         {
 215                 .ctl_name       = CTL_DEV,
 216                 .procname       = "dev",
 217                 .mode           = 0555,
 218                 .child          = dev_table,
 219         },
 220 /*
 221  * NOTE: do not add new entries to this table unless you have read
 222  * Documentation/sysctl/ctl_unnumbered.txt
 223  */
 224         { .ctl_name = 0 }
 225 };
 226
 227 #ifdef CONFIG_SCHED_DEBUG
 228 static unsigned long min_sched_granularity_ns = 100000;         /* 100 usecs */
 229 static unsigned long max_sched_granularity_ns = NSEC_PER_SEC;   /* 1 second */
 230 static unsigned long min_wakeup_granularity_ns;                 /* 0 usecs */
 231 static unsigned long max_wakeup_granularity_ns = NSEC_PER_SEC;  /* 1 second */
 232 #endif
 233
 234 static struct ctl_table kern_table[] = {
 235 #ifdef CONFIG_SCHED_DEBUG
 236         {
 237                 .ctl_name       = CTL_UNNUMBERED,
 238                 .procname       = "sched_min_granularity_ns",
 239                 .data           = &sysctl_sched_min_granularity,
 240                 .maxlen         = sizeof(unsigned int),
 241                 .mode           = 0644,
 242                 .proc_handler   = &sched_nr_latency_handler,
 243                 .strategy       = &sysctl_intvec,
 244                 .extra1         = &min_sched_granularity_ns,
 245                 .extra2         = &max_sched_granularity_ns,
 246         },
 247         {
 248                 .ctl_name       = CTL_UNNUMBERED,
 249                 .procname       = "sched_latency_ns",
 250                 .data           = &sysctl_sched_latency,
 251                 .maxlen         = sizeof(unsigned int),
 252                 .mode           = 0644,
 253                 .proc_handler   = &sched_nr_latency_handler,
 254                 .strategy       = &sysctl_intvec,
 255                 .extra1         = &min_sched_granularity_ns,
 256                 .extra2         = &max_sched_granularity_ns,
 257         },
 258         {
 259                 .ctl_name       = CTL_UNNUMBERED,
 260                 .procname       = "sched_wakeup_granularity_ns",
 261                 .data           = &sysctl_sched_wakeup_granularity,
 262                 .maxlen         = sizeof(unsigned int),
 263                 .mode           = 0644,
 264                 .proc_handler   = &proc_dointvec_minmax,
 265                 .strategy       = &sysctl_intvec,
 266                 .extra1         = &min_wakeup_granularity_ns,
 267                 .extra2         = &max_wakeup_granularity_ns,
 268         },
 269         {
 270                 .ctl_name       = CTL_UNNUMBERED,
 271                 .procname       = "sched_batch_wakeup_granularity_ns",
 272                 .data           = &sysctl_sched_batch_wakeup_granularity,
 273                 .maxlen         = sizeof(unsigned int),
 274                 .mode           = 0644,
 275                 .proc_handler   = &proc_dointvec_minmax,
 276                 .strategy       = &sysctl_intvec,
 277                 .extra1         = &min_wakeup_granularity_ns,
 278                 .extra2         = &max_wakeup_granularity_ns,
 279         },
 280         {
 281                 .ctl_name       = CTL_UNNUMBERED,
 282                 .procname       = "sched_child_runs_first",
 283                 .data           = &sysctl_sched_child_runs_first,
 284                 .maxlen         = sizeof(unsigned int),
 285                 .mode           = 0644,
 286                 .proc_handler   = &proc_dointvec,
 287         },
 288         {
 289                 .ctl_name       = CTL_UNNUMBERED,
 290                 .procname       = "sched_features",
 291                 .data           = &sysctl_sched_features,
 292                 .maxlen         = sizeof(unsigned int),
 293                 .mode           = 0644,
 294                 .proc_handler   = &proc_dointvec,
 295         },
 296         {
 297                 .ctl_name       = CTL_UNNUMBERED,
 298                 .procname       = "sched_migration_cost",
 299                 .data           = &sysctl_sched_migration_cost,
 300                 .maxlen         = sizeof(unsigned int),
 301                 .mode           = 0644,
 302                 .proc_handler   = &proc_dointvec,
 303         },
 304 #endif
 305         {
 306                 .ctl_name       = CTL_UNNUMBERED,
 307                 .procname       = "sched_compat_yield",
 308                 .data           = &sysctl_sched_compat_yield,
 309                 .maxlen         = sizeof(unsigned int),
 310                 .mode           = 0644,
 311                 .proc_handler   = &proc_dointvec,
 312         },
 313 #ifdef CONFIG_PROVE_LOCKING
 314         {
 315                 .ctl_name       = CTL_UNNUMBERED,
 316                 .procname       = "prove_locking",
 317                 .data           = &prove_locking,
 318                 .maxlen         = sizeof(int),
 319                 .mode           = 0644,
 320                 .proc_handler   = &proc_dointvec,
 321         },
 322 #endif
 323 #ifdef CONFIG_LOCK_STAT
 324         {
 325                 .ctl_name       = CTL_UNNUMBERED,
 326                 .procname       = "lock_stat",
 327                 .data           = &lock_stat,
 328                 .maxlen         = sizeof(int),
 329                 .mode           = 0644,
 330                 .proc_handler   = &proc_dointvec,
 331         },
 332 #endif
 333         {
 334                 .ctl_name       = KERN_PANIC,
 335                 .procname       = "panic",
 336                 .data           = &panic_timeout,
 337                 .maxlen         = sizeof(int),
 338                 .mode           = 0644,
 339                 .proc_handler   = &proc_dointvec,
 340         },
 341         {
 342                 .ctl_name       = KERN_CORE_USES_PID,
 343                 .procname       = "core_uses_pid",
 344                 .data           = &core_uses_pid,
 345                 .maxlen         = sizeof(int),
 346                 .mode           = 0644,
 347                 .proc_handler   = &proc_dointvec,
 348         },
 349 #ifdef CONFIG_AUDITSYSCALL
 350         {
 351                 .ctl_name       = CTL_UNNUMBERED,
 352                 .procname       = "audit_argv_kb",
 353                 .data           = &audit_argv_kb,
 354                 .maxlen         = sizeof(int),
 355                 .mode           = 0644,
 356                 .proc_handler   = &proc_dointvec,
 357         },
 358 #endif
 359         {
 360                 .ctl_name       = KERN_CORE_PATTERN,
 361                 .procname       = "core_pattern",
 362                 .data           = core_pattern,
 363                 .maxlen         = CORENAME_MAX_SIZE,
 364                 .mode           = 0644,
 365                 .proc_handler   = &proc_dostring,
 366                 .strategy       = &sysctl_string,
 367         },
 368 #ifdef CONFIG_PROC_SYSCTL
 369         {
 370                 .procname       = "tainted",
 371                 .data           = &tainted,
 372                 .maxlen         = sizeof(int),
 373                 .mode           = 0644,
 374                 .proc_handler   = &proc_dointvec_taint,
 375         },
 376 #endif
 377 #ifdef CONFIG_SECURITY_CAPABILITIES
 378         {
 379                 .procname       = "cap-bound",
 380                 .data           = &cap_bset,
 381                 .maxlen         = sizeof(kernel_cap_t),
 382                 .mode           = 0600,
 383                 .proc_handler   = &proc_dointvec_bset,
 384         },
 385 #endif /* def CONFIG_SECURITY_CAPABILITIES */
 386 #ifdef CONFIG_BLK_DEV_INITRD
 387         {
 388                 .ctl_name       = KERN_REALROOTDEV,
 389                 .procname       = "real-root-dev",
 390                 .data           = &real_root_dev,
 391                 .maxlen         = sizeof(int),
 392                 .mode           = 0644,
 393                 .proc_handler   = &proc_dointvec,
 394         },
 395 #endif
 396         {
 397                 .ctl_name       = CTL_UNNUMBERED,
 398                 .procname       = "print-fatal-signals",
 399                 .data           = &print_fatal_signals,
 400                 .maxlen         = sizeof(int),
 401                 .mode           = 0644,
 402                 .proc_handler   = &proc_dointvec,
 403         },
 404 #ifdef __sparc__
 405         {
 406                 .ctl_name       = KERN_SPARC_REBOOT,
 407                 .procname       = "reboot-cmd",
 408                 .data           = reboot_command,
 409                 .maxlen         = 256,
 410                 .mode           = 0644,
 411                 .proc_handler   = &proc_dostring,
 412                 .strategy       = &sysctl_string,
 413         },
 414         {
 415                 .ctl_name       = KERN_SPARC_STOP_A,
 416                 .procname       = "stop-a",
 417                 .data           = &stop_a_enabled,
 418                 .maxlen         = sizeof (int),
 419                 .mode           = 0644,
 420                 .proc_handler   = &proc_dointvec,
 421         },
 422         {
 423                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 424                 .procname       = "scons-poweroff",
 425                 .data           = &scons_pwroff,
 426                 .maxlen         = sizeof (int),
 427                 .mode           = 0644,
 428                 .proc_handler   = &proc_dointvec,
 429         },
 430 #endif
 431 #ifdef __hppa__
 432         {
 433                 .ctl_name       = KERN_HPPA_PWRSW,
 434                 .procname       = "soft-power",
 435                 .data           = &pwrsw_enabled,
 436                 .maxlen         = sizeof (int),
 437                 .mode           = 0644,
 438                 .proc_handler   = &proc_dointvec,
 439         },
 440         {
 441                 .ctl_name       = KERN_HPPA_UNALIGNED,
 442                 .procname       = "unaligned-trap",
 443                 .data           = &unaligned_enabled,
 444                 .maxlen         = sizeof (int),
 445                 .mode           = 0644,
 446                 .proc_handler   = &proc_dointvec,
 447         },
 448 #endif
 449         {
 450                 .ctl_name       = KERN_CTLALTDEL,
 451                 .procname       = "ctrl-alt-del",
 452                 .data           = &C_A_D,
 453                 .maxlen         = sizeof(int),
 454                 .mode           = 0644,
 455                 .proc_handler   = &proc_dointvec,
 456         },
 457         {
 458                 .ctl_name       = KERN_PRINTK,
 459                 .procname       = "printk",
 460                 .data           = &console_loglevel,
 461                 .maxlen         = 4*sizeof(int),
 462                 .mode           = 0644,
 463                 .proc_handler   = &proc_dointvec,
 464         },
 465 #ifdef CONFIG_KMOD
 466         {
 467                 .ctl_name       = KERN_MODPROBE,
 468                 .procname       = "modprobe",
 469                 .data           = &modprobe_path,
 470                 .maxlen         = KMOD_PATH_LEN,
 471                 .mode           = 0644,
 472                 .proc_handler   = &proc_dostring,
 473                 .strategy       = &sysctl_string,
 474         },
 475 #endif
 476 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 477         {
 478                 .ctl_name       = KERN_HOTPLUG,
 479                 .procname       = "hotplug",
 480                 .data           = &uevent_helper,
 481                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 482                 .mode           = 0644,
 483                 .proc_handler   = &proc_dostring,
 484                 .strategy       = &sysctl_string,
 485         },
 486 #endif
 487 #ifdef CONFIG_CHR_DEV_SG
 488         {
 489                 .ctl_name       = KERN_SG_BIG_BUFF,
 490                 .procname       = "sg-big-buff",
 491                 .data           = &sg_big_buff,
 492                 .maxlen         = sizeof (int),
 493                 .mode           = 0444,
 494                 .proc_handler   = &proc_dointvec,
 495         },
 496 #endif
 497 #ifdef CONFIG_BSD_PROCESS_ACCT
 498         {
 499                 .ctl_name       = KERN_ACCT,
 500                 .procname       = "acct",
 501                 .data           = &acct_parm,
 502                 .maxlen         = 3*sizeof(int),
 503                 .mode           = 0644,
 504                 .proc_handler   = &proc_dointvec,
 505         },
 506 #endif
 507 #ifdef CONFIG_MAGIC_SYSRQ
 508         {
 509                 .ctl_name       = KERN_SYSRQ,
 510                 .procname       = "sysrq",
 511                 .data           = &__sysrq_enabled,
 512                 .maxlen         = sizeof (int),
 513                 .mode           = 0644,
 514                 .proc_handler   = &proc_dointvec,
 515         },
 516 #endif
 517 #ifdef CONFIG_PROC_SYSCTL
 518         {
 519                 .procname       = "cad_pid",
 520                 .data           = NULL,
 521                 .maxlen         = sizeof (int),
 522                 .mode           = 0600,
 523                 .proc_handler   = &proc_do_cad_pid,
 524         },
 525 #endif
 526         {
 527                 .ctl_name       = KERN_MAX_THREADS,
 528                 .procname       = "threads-max",
 529                 .data           = &max_threads,
 530                 .maxlen         = sizeof(int),
 531                 .mode           = 0644,
 532                 .proc_handler   = &proc_dointvec,
 533         },
 534         {
 535                 .ctl_name       = KERN_RANDOM,
 536                 .procname       = "random",
 537                 .mode           = 0555,
 538                 .child          = random_table,
 539         },
 540         {
 541                 .ctl_name       = KERN_OVERFLOWUID,
 542                 .procname       = "overflowuid",
 543                 .data           = &overflowuid,
 544                 .maxlen         = sizeof(int),
 545                 .mode           = 0644,
 546                 .proc_handler   = &proc_dointvec_minmax,
 547                 .strategy       = &sysctl_intvec,
 548                 .extra1         = &minolduid,
 549                 .extra2         = &maxolduid,
 550         },
 551         {
 552                 .ctl_name       = KERN_OVERFLOWGID,
 553                 .procname       = "overflowgid",
 554                 .data           = &overflowgid,
 555                 .maxlen         = sizeof(int),
 556                 .mode           = 0644,
 557                 .proc_handler   = &proc_dointvec_minmax,
 558                 .strategy       = &sysctl_intvec,
 559                 .extra1         = &minolduid,
 560                 .extra2         = &maxolduid,
 561         },
 562 #ifdef CONFIG_S390
 563 #ifdef CONFIG_MATHEMU
 564         {
 565                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 566                 .procname       = "ieee_emulation_warnings",
 567                 .data           = &sysctl_ieee_emulation_warnings,
 568                 .maxlen         = sizeof(int),
 569                 .mode           = 0644,
 570                 .proc_handler   = &proc_dointvec,
 571         },
 572 #endif
 573 #ifdef CONFIG_NO_IDLE_HZ
 574         {
 575                 .ctl_name       = KERN_HZ_TIMER,
 576                 .procname       = "hz_timer",
 577                 .data           = &sysctl_hz_timer,
 578                 .maxlen         = sizeof(int),
 579                 .mode           = 0644,
 580                 .proc_handler   = &proc_dointvec,
 581         },
 582 #endif
 583         {
 584                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 585                 .procname       = "userprocess_debug",
 586                 .data           = &sysctl_userprocess_debug,
 587                 .maxlen         = sizeof(int),
 588                 .mode           = 0644,
 589                 .proc_handler   = &proc_dointvec,
 590         },
 591 #endif
 592         {
 593                 .ctl_name       = KERN_PIDMAX,
 594                 .procname       = "pid_max",
 595                 .data           = &pid_max,
 596                 .maxlen         = sizeof (int),
 597                 .mode           = 0644,
 598                 .proc_handler   = &proc_dointvec_minmax,
 599                 .strategy       = sysctl_intvec,
 600                 .extra1         = &pid_max_min,
 601                 .extra2         = &pid_max_max,
 602         },
 603         {
 604                 .ctl_name       = KERN_PANIC_ON_OOPS,
 605                 .procname       = "panic_on_oops",
 606                 .data           = &panic_on_oops,
 607                 .maxlen         = sizeof(int),
 608                 .mode           = 0644,
 609                 .proc_handler   = &proc_dointvec,
 610         },
 611         {
 612                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 613                 .procname       = "printk_ratelimit",
 614                 .data           = &printk_ratelimit_jiffies,
 615                 .maxlen         = sizeof(int),
 616                 .mode           = 0644,
 617                 .proc_handler   = &proc_dointvec_jiffies,
 618                 .strategy       = &sysctl_jiffies,
 619         },
 620         {
 621                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 622                 .procname       = "printk_ratelimit_burst",
 623                 .data           = &printk_ratelimit_burst,
 624                 .maxlen         = sizeof(int),
 625                 .mode           = 0644,
 626                 .proc_handler   = &proc_dointvec,
 627         },
 628         {
 629                 .ctl_name       = KERN_NGROUPS_MAX,
 630                 .procname       = "ngroups_max",
 631                 .data           = &ngroups_max,
 632                 .maxlen         = sizeof (int),
 633                 .mode           = 0444,
 634                 .proc_handler   = &proc_dointvec,
 635         },
 636 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 637         {
 638                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 639                 .procname       = "unknown_nmi_panic",
 640                 .data           = &unknown_nmi_panic,
 641                 .maxlen         = sizeof (int),
 642                 .mode           = 0644,
 643                 .proc_handler   = &proc_dointvec,
 644         },
 645         {
 646                 .procname       = "nmi_watchdog",
 647                 .data           = &nmi_watchdog_enabled,
 648                 .maxlen         = sizeof (int),
 649                 .mode           = 0644,
 650                 .proc_handler   = &proc_nmi_enabled,
 651         },
 652 #endif
 653 #if defined(CONFIG_X86)
 654         {
 655                 .ctl_name       = KERN_PANIC_ON_NMI,
 656                 .procname       = "panic_on_unrecovered_nmi",
 657                 .data           = &panic_on_unrecovered_nmi,
 658                 .maxlen         = sizeof(int),
 659                 .mode           = 0644,
 660                 .proc_handler   = &proc_dointvec,
 661         },
 662         {
 663                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 664                 .procname       = "bootloader_type",
 665                 .data           = &bootloader_type,
 666                 .maxlen         = sizeof (int),
 667                 .mode           = 0444,
 668                 .proc_handler   = &proc_dointvec,
 669         },
 670         {
 671                 .ctl_name       = CTL_UNNUMBERED,
 672                 .procname       = "kstack_depth_to_print",
 673                 .data           = &kstack_depth_to_print,
 674                 .maxlen         = sizeof(int),
 675                 .mode           = 0644,
 676                 .proc_handler   = &proc_dointvec,
 677         },
 678 #endif
 679 #if defined(CONFIG_MMU)
 680         {
 681                 .ctl_name       = KERN_RANDOMIZE,
 682                 .procname       = "randomize_va_space",
 683                 .data           = &randomize_va_space,
 684                 .maxlen         = sizeof(int),
 685                 .mode           = 0644,
 686                 .proc_handler   = &proc_dointvec,
 687         },
 688 #endif
 689 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 690         {
 691                 .ctl_name       = KERN_SPIN_RETRY,
 692                 .procname       = "spin_retry",
 693                 .data           = &spin_retry,
 694                 .maxlen         = sizeof (int),
 695                 .mode           = 0644,
 696                 .proc_handler   = &proc_dointvec,
 697         },
 698 #endif
 699 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 700         {
 701                 .procname       = "acpi_video_flags",
 702                 .data           = &acpi_realmode_flags,
 703                 .maxlen         = sizeof (unsigned long),
 704                 .mode           = 0644,
 705                 .proc_handler   = &proc_doulongvec_minmax,
 706         },
 707 #endif
 708 #ifdef CONFIG_IA64
 709         {
 710                 .ctl_name       = KERN_IA64_UNALIGNED,
 711                 .procname       = "ignore-unaligned-usertrap",
 712                 .data           = &no_unaligned_warning,
 713                 .maxlen         = sizeof (int),
 714                 .mode           = 0644,
 715                 .proc_handler   = &proc_dointvec,
 716         },
 717 #endif
 718 #ifdef CONFIG_DETECT_SOFTLOCKUP
 719         {
 720                 .ctl_name       = CTL_UNNUMBERED,
 721                 .procname       = "softlockup_thresh",
 722                 .data           = &softlockup_thresh,
 723                 .maxlen         = sizeof(int),
 724                 .mode           = 0644,
 725                 .proc_handler   = &proc_dointvec_minmax,
 726                 .strategy       = &sysctl_intvec,
 727                 .extra1         = &one,
 728                 .extra2         = &sixty,
 729         },
 730 #endif
 731 #ifdef CONFIG_COMPAT
 732         {
 733                 .ctl_name       = KERN_COMPAT_LOG,
 734                 .procname       = "compat-log",
 735                 .data           = &compat_log,
 736                 .maxlen         = sizeof (int),
 737                 .mode           = 0644,
 738                 .proc_handler   = &proc_dointvec,
 739         },
 740 #endif
 741 #ifdef CONFIG_RT_MUTEXES
 742         {
 743                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 744                 .procname       = "max_lock_depth",
 745                 .data           = &max_lock_depth,
 746                 .maxlen         = sizeof(int),
 747                 .mode           = 0644,
 748                 .proc_handler   = &proc_dointvec,
 749         },
 750 #endif
 751 #ifdef CONFIG_PROC_FS
 752         {
 753                 .ctl_name       = CTL_UNNUMBERED,
 754                 .procname       = "maps_protect",
 755                 .data           = &maps_protect,
 756                 .maxlen         = sizeof(int),
 757                 .mode           = 0644,
 758                 .proc_handler   = &proc_dointvec,
 759         },
 760 #endif
 761         {
 762                 .ctl_name       = CTL_UNNUMBERED,
 763                 .procname       = "poweroff_cmd",
 764                 .data           = &poweroff_cmd,
 765                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 766                 .mode           = 0644,
 767                 .proc_handler   = &proc_dostring,
 768                 .strategy       = &sysctl_string,
 769         },
 770 /*
 771  * NOTE: do not add new entries to this table unless you have read
 772  * Documentation/sysctl/ctl_unnumbered.txt
 773  */
 774         { .ctl_name = 0 }
 775 };
 776
 777 static struct ctl_table vm_table[] = {
 778         {
 779                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 780                 .procname       = "overcommit_memory",
 781                 .data           = &sysctl_overcommit_memory,
 782                 .maxlen         = sizeof(sysctl_overcommit_memory),
 783                 .mode           = 0644,
 784                 .proc_handler   = &proc_dointvec,
 785         },
 786         {
 787                 .ctl_name       = VM_PANIC_ON_OOM,
 788                 .procname       = "panic_on_oom",
 789                 .data           = &sysctl_panic_on_oom,
 790                 .maxlen         = sizeof(sysctl_panic_on_oom),
 791                 .mode           = 0644,
 792                 .proc_handler   = &proc_dointvec,
 793         },
 794         {
 795                 .ctl_name       = CTL_UNNUMBERED,
 796                 .procname       = "oom_kill_allocating_task",
 797                 .data           = &sysctl_oom_kill_allocating_task,
 798                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
 799                 .mode           = 0644,
 800                 .proc_handler   = &proc_dointvec,
 801         },
 802         {
 803                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 804                 .procname       = "overcommit_ratio",
 805                 .data           = &sysctl_overcommit_ratio,
 806                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 807                 .mode           = 0644,
 808                 .proc_handler   = &proc_dointvec,
 809         },
 810         {
 811                 .ctl_name       = VM_PAGE_CLUSTER,
 812                 .procname       = "page-cluster",
 813                 .data           = &page_cluster,
 814                 .maxlen         = sizeof(int),
 815                 .mode           = 0644,
 816                 .proc_handler   = &proc_dointvec,
 817         },
 818         {
 819                 .ctl_name       = VM_DIRTY_BACKGROUND,
 820                 .procname       = "dirty_background_ratio",
 821                 .data           = &dirty_background_ratio,
 822                 .maxlen         = sizeof(dirty_background_ratio),
 823                 .mode           = 0644,
 824                 .proc_handler   = &proc_dointvec_minmax,
 825                 .strategy       = &sysctl_intvec,
 826                 .extra1         = &zero,
 827                 .extra2         = &one_hundred,
 828         },
 829         {
 830                 .ctl_name       = VM_DIRTY_RATIO,
 831                 .procname       = "dirty_ratio",
 832                 .data           = &vm_dirty_ratio,
 833                 .maxlen         = sizeof(vm_dirty_ratio),
 834                 .mode           = 0644,
 835                 .proc_handler   = &dirty_ratio_handler,
 836                 .strategy       = &sysctl_intvec,
 837                 .extra1         = &zero,
 838                 .extra2         = &one_hundred,
 839         },
 840         {
 841                 .procname       = "dirty_writeback_centisecs",
 842                 .data           = &dirty_writeback_interval,
 843                 .maxlen         = sizeof(dirty_writeback_interval),
 844                 .mode           = 0644,
 845                 .proc_handler   = &dirty_writeback_centisecs_handler,
 846         },
 847         {
 848                 .procname       = "dirty_expire_centisecs",
 849                 .data           = &dirty_expire_interval,
 850                 .maxlen         = sizeof(dirty_expire_interval),
 851                 .mode           = 0644,
 852                 .proc_handler   = &proc_dointvec_userhz_jiffies,
 853         },
 854         {
 855                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 856                 .procname       = "nr_pdflush_threads",
 857                 .data           = &nr_pdflush_threads,
 858                 .maxlen         = sizeof nr_pdflush_threads,
 859                 .mode           = 0444 /* read-only*/,
 860                 .proc_handler   = &proc_dointvec,
 861         },
 862         {
 863                 .ctl_name       = VM_SWAPPINESS,
 864                 .procname       = "swappiness",
 865                 .data           = &vm_swappiness,
 866                 .maxlen         = sizeof(vm_swappiness),
 867                 .mode           = 0644,
 868                 .proc_handler   = &proc_dointvec_minmax,
 869                 .strategy       = &sysctl_intvec,
 870                 .extra1         = &zero,
 871                 .extra2         = &one_hundred,
 872         },
 873 #ifdef CONFIG_HUGETLB_PAGE
 874          {
 875                 .procname       = "nr_hugepages",
 876                 .data           = &max_huge_pages,
 877                 .maxlen         = sizeof(unsigned long),
 878                 .mode           = 0644,
 879                 .proc_handler   = &hugetlb_sysctl_handler,
 880                 .extra1         = (void *)&hugetlb_zero,
 881                 .extra2         = (void *)&hugetlb_infinity,
 882          },
 883          {
 884                 .ctl_name       = VM_HUGETLB_GROUP,
 885                 .procname       = "hugetlb_shm_group",
 886                 .data           = &sysctl_hugetlb_shm_group,
 887                 .maxlen         = sizeof(gid_t),
 888                 .mode           = 0644,
 889                 .proc_handler   = &proc_dointvec,
 890          },
 891          {
 892                 .ctl_name       = CTL_UNNUMBERED,
 893                 .procname       = "hugepages_treat_as_movable",
 894                 .data           = &hugepages_treat_as_movable,
 895                 .maxlen         = sizeof(int),
 896                 .mode           = 0644,
 897                 .proc_handler   = &hugetlb_treat_movable_handler,
 898         },
 899         {
 900                 .ctl_name       = CTL_UNNUMBERED,
 901                 .procname       = "hugetlb_dynamic_pool",
 902                 .data           = &hugetlb_dynamic_pool,
 903                 .maxlen         = sizeof(hugetlb_dynamic_pool),
 904                 .mode           = 0644,
 905                 .proc_handler   = &proc_dointvec,
 906         },
 907 #endif
 908         {
 909                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 910                 .procname       = "lowmem_reserve_ratio",
 911                 .data           = &sysctl_lowmem_reserve_ratio,
 912                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 913                 .mode           = 0644,
 914                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 915                 .strategy       = &sysctl_intvec,
 916         },
 917         {
 918                 .ctl_name       = VM_DROP_PAGECACHE,
 919                 .procname       = "drop_caches",
 920                 .data           = &sysctl_drop_caches,
 921                 .maxlen         = sizeof(int),
 922                 .mode           = 0644,
 923                 .proc_handler   = drop_caches_sysctl_handler,
 924                 .strategy       = &sysctl_intvec,
 925         },
 926         {
 927                 .ctl_name       = VM_MIN_FREE_KBYTES,
 928                 .procname       = "min_free_kbytes",
 929                 .data           = &min_free_kbytes,
 930                 .maxlen         = sizeof(min_free_kbytes),
 931                 .mode           = 0644,
 932                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 933                 .strategy       = &sysctl_intvec,
 934                 .extra1         = &zero,
 935         },
 936         {
 937                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
 938                 .procname       = "percpu_pagelist_fraction",
 939                 .data           = &percpu_pagelist_fraction,
 940                 .maxlen         = sizeof(percpu_pagelist_fraction),
 941                 .mode           = 0644,
 942                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
 943                 .strategy       = &sysctl_intvec,
 944                 .extra1         = &min_percpu_pagelist_fract,
 945         },
 946 #ifdef CONFIG_MMU
 947         {
 948                 .ctl_name       = VM_MAX_MAP_COUNT,
 949                 .procname       = "max_map_count",
 950                 .data           = &sysctl_max_map_count,
 951                 .maxlen         = sizeof(sysctl_max_map_count),
 952                 .mode           = 0644,
 953                 .proc_handler   = &proc_dointvec
 954         },
 955 #endif
 956         {
 957                 .ctl_name       = VM_LAPTOP_MODE,
 958                 .procname       = "laptop_mode",
 959                 .data           = &laptop_mode,
 960                 .maxlen         = sizeof(laptop_mode),
 961                 .mode           = 0644,
 962                 .proc_handler   = &proc_dointvec_jiffies,
 963                 .strategy       = &sysctl_jiffies,
 964         },
 965         {
 966                 .ctl_name       = VM_BLOCK_DUMP,
 967                 .procname       = "block_dump",
 968                 .data           = &block_dump,
 969                 .maxlen         = sizeof(block_dump),
 970                 .mode           = 0644,
 971                 .proc_handler   = &proc_dointvec,
 972                 .strategy       = &sysctl_intvec,
 973                 .extra1         = &zero,
 974         },
 975         {
 976                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 977                 .procname       = "vfs_cache_pressure",
 978                 .data           = &sysctl_vfs_cache_pressure,
 979                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 980                 .mode           = 0644,
 981                 .proc_handler   = &proc_dointvec,
 982                 .strategy       = &sysctl_intvec,
 983                 .extra1         = &zero,
 984         },
 985 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 986         {
 987                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 988                 .procname       = "legacy_va_layout",
 989                 .data           = &sysctl_legacy_va_layout,
 990                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 991                 .mode           = 0644,
 992                 .proc_handler   = &proc_dointvec,
 993                 .strategy       = &sysctl_intvec,
 994                 .extra1         = &zero,
 995         },
 996 #endif
 997 #ifdef CONFIG_NUMA
 998         {
 999                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
1000                 .procname       = "zone_reclaim_mode",
1001                 .data           = &zone_reclaim_mode,
1002                 .maxlen         = sizeof(zone_reclaim_mode),
1003                 .mode           = 0644,
1004                 .proc_handler   = &proc_dointvec,
1005                 .strategy       = &sysctl_intvec,
1006                 .extra1         = &zero,
1007         },
1008         {
1009                 .ctl_name       = VM_MIN_UNMAPPED,
1010                 .procname       = "min_unmapped_ratio",
1011                 .data           = &sysctl_min_unmapped_ratio,
1012                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1013                 .mode           = 0644,
1014                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1015                 .strategy       = &sysctl_intvec,
1016                 .extra1         = &zero,
1017                 .extra2         = &one_hundred,
1018         },
1019         {
1020                 .ctl_name       = VM_MIN_SLAB,
1021                 .procname       = "min_slab_ratio",
1022                 .data           = &sysctl_min_slab_ratio,
1023                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1024                 .mode           = 0644,
1025                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1026                 .strategy       = &sysctl_intvec,
1027                 .extra1         = &zero,
1028                 .extra2         = &one_hundred,
1029         },
1030 #endif
1031 #ifdef CONFIG_SMP
1032         {
1033                 .ctl_name       = CTL_UNNUMBERED,
1034                 .procname       = "stat_interval",
1035                 .data           = &sysctl_stat_interval,
1036                 .maxlen         = sizeof(sysctl_stat_interval),
1037                 .mode           = 0644,
1038                 .proc_handler   = &proc_dointvec_jiffies,
1039                 .strategy       = &sysctl_jiffies,
1040         },
1041 #endif
1042 #ifdef CONFIG_SECURITY
1043         {
1044                 .ctl_name       = CTL_UNNUMBERED,
1045                 .procname       = "mmap_min_addr",
1046                 .data           = &mmap_min_addr,
1047                 .maxlen         = sizeof(unsigned long),
1048                 .mode           = 0644,
1049                 .proc_handler   = &proc_doulongvec_minmax,
1050         },
1051 #endif
1052 #ifdef CONFIG_NUMA
1053         {
1054                 .ctl_name       = CTL_UNNUMBERED,
1055                 .procname       = "numa_zonelist_order",
1056                 .data           = &numa_zonelist_order,
1057                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1058                 .mode           = 0644,
1059                 .proc_handler   = &numa_zonelist_order_handler,
1060                 .strategy       = &sysctl_string,
1061         },
1062 #endif
1063 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1064    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1065         {
1066                 .ctl_name       = VM_VDSO_ENABLED,
1067                 .procname       = "vdso_enabled",
1068                 .data           = &vdso_enabled,
1069                 .maxlen         = sizeof(vdso_enabled),
1070                 .mode           = 0644,
1071                 .proc_handler   = &proc_dointvec,
1072                 .strategy       = &sysctl_intvec,
1073                 .extra1         = &zero,
1074         },
1075 #endif
1076 /*
1077  * NOTE: do not add new entries to this table unless you have read
1078  * Documentation/sysctl/ctl_unnumbered.txt
1079  */
1080         { .ctl_name = 0 }
1081 };
1082
1083 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1084 static struct ctl_table binfmt_misc_table[] = {
1085         { .ctl_name = 0 }
1086 };
1087 #endif
1088
1089 static struct ctl_table fs_table[] = {
1090         {
1091                 .ctl_name       = FS_NRINODE,
1092                 .procname       = "inode-nr",
1093                 .data           = &inodes_stat,
1094                 .maxlen         = 2*sizeof(int),
1095                 .mode           = 0444,
1096                 .proc_handler   = &proc_dointvec,
1097         },
1098         {
1099                 .ctl_name       = FS_STATINODE,
1100                 .procname       = "inode-state",
1101                 .data           = &inodes_stat,
1102                 .maxlen         = 7*sizeof(int),
1103                 .mode           = 0444,
1104                 .proc_handler   = &proc_dointvec,
1105         },
1106         {
1107                 .procname       = "file-nr",
1108                 .data           = &files_stat,
1109                 .maxlen         = 3*sizeof(int),
1110                 .mode           = 0444,
1111                 .proc_handler   = &proc_nr_files,
1112         },
1113         {
1114                 .ctl_name       = FS_MAXFILE,
1115                 .procname       = "file-max",
1116                 .data           = &files_stat.max_files,
1117                 .maxlen         = sizeof(int),
1118                 .mode           = 0644,
1119                 .proc_handler   = &proc_dointvec,
1120         },
1121         {
1122                 .ctl_name       = FS_DENTRY,
1123                 .procname       = "dentry-state",
1124                 .data           = &dentry_stat,
1125                 .maxlen         = 6*sizeof(int),
1126                 .mode           = 0444,
1127                 .proc_handler   = &proc_dointvec,
1128         },
1129         {
1130                 .ctl_name       = FS_OVERFLOWUID,
1131                 .procname       = "overflowuid",
1132                 .data           = &fs_overflowuid,
1133                 .maxlen         = sizeof(int),
1134                 .mode           = 0644,
1135                 .proc_handler   = &proc_dointvec_minmax,
1136                 .strategy       = &sysctl_intvec,
1137                 .extra1         = &minolduid,
1138                 .extra2         = &maxolduid,
1139         },
1140         {
1141                 .ctl_name       = FS_OVERFLOWGID,
1142                 .procname       = "overflowgid",
1143                 .data           = &fs_overflowgid,
1144                 .maxlen         = sizeof(int),
1145                 .mode           = 0644,
1146                 .proc_handler   = &proc_dointvec_minmax,
1147                 .strategy       = &sysctl_intvec,
1148                 .extra1         = &minolduid,
1149                 .extra2         = &maxolduid,
1150         },
1151         {
1152                 .ctl_name       = FS_LEASES,
1153                 .procname       = "leases-enable",
1154                 .data           = &leases_enable,
1155                 .maxlen         = sizeof(int),
1156                 .mode           = 0644,
1157                 .proc_handler   = &proc_dointvec,
1158         },
1159 #ifdef CONFIG_DNOTIFY
1160         {
1161                 .ctl_name       = FS_DIR_NOTIFY,
1162                 .procname       = "dir-notify-enable",
1163                 .data           = &dir_notify_enable,
1164                 .maxlen         = sizeof(int),
1165                 .mode           = 0644,
1166                 .proc_handler   = &proc_dointvec,
1167         },
1168 #endif
1169 #ifdef CONFIG_MMU
1170         {
1171                 .ctl_name       = FS_LEASE_TIME,
1172                 .procname       = "lease-break-time",
1173                 .data           = &lease_break_time,
1174                 .maxlen         = sizeof(int),
1175                 .mode           = 0644,
1176                 .proc_handler   = &proc_dointvec_minmax,
1177                 .strategy       = &sysctl_intvec,
1178                 .extra1         = &zero,
1179                 .extra2         = &two,
1180         },
1181         {
1182                 .procname       = "aio-nr",
1183                 .data           = &aio_nr,
1184                 .maxlen         = sizeof(aio_nr),
1185                 .mode           = 0444,
1186                 .proc_handler   = &proc_doulongvec_minmax,
1187         },
1188         {
1189                 .procname       = "aio-max-nr",
1190                 .data           = &aio_max_nr,
1191                 .maxlen         = sizeof(aio_max_nr),
1192                 .mode           = 0644,
1193                 .proc_handler   = &proc_doulongvec_minmax,
1194         },
1195 #ifdef CONFIG_INOTIFY_USER
1196         {
1197                 .ctl_name       = FS_INOTIFY,
1198                 .procname       = "inotify",
1199                 .mode           = 0555,
1200                 .child          = inotify_table,
1201         },
1202 #endif
1203 #endif
1204         {
1205                 .ctl_name       = KERN_SETUID_DUMPABLE,
1206                 .procname       = "suid_dumpable",
1207                 .data           = &suid_dumpable,
1208                 .maxlen         = sizeof(int),
1209                 .mode           = 0644,
1210                 .proc_handler   = &proc_dointvec,
1211         },
1212 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1213         {
1214                 .ctl_name       = CTL_UNNUMBERED,
1215                 .procname       = "binfmt_misc",
1216                 .mode           = 0555,
1217                 .child          = binfmt_misc_table,
1218         },
1219 #endif
1220 /*
1221  * NOTE: do not add new entries to this table unless you have read
1222  * Documentation/sysctl/ctl_unnumbered.txt
1223  */
1224         { .ctl_name = 0 }
1225 };
1226
1227 static struct ctl_table debug_table[] = {
1228 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1229         {
1230                 .ctl_name       = CTL_UNNUMBERED,
1231                 .procname       = "exception-trace",
1232                 .data           = &show_unhandled_signals,
1233                 .maxlen         = sizeof(int),
1234                 .mode           = 0644,
1235                 .proc_handler   = proc_dointvec
1236         },
1237 #endif
1238         { .ctl_name = 0 }
1239 };
1240
1241 static struct ctl_table dev_table[] = {
1242         { .ctl_name = 0 }
1243 };
1244
1245 static DEFINE_SPINLOCK(sysctl_lock);
1246
1247 /* called under sysctl_lock */
1248 static int use_table(struct ctl_table_header *p)
1249 {
1250         if (unlikely(p->unregistering))
1251                 return 0;
1252         p->used++;
1253         return 1;
1254 }
1255
1256 /* called under sysctl_lock */
1257 static void unuse_table(struct ctl_table_header *p)
1258 {
1259         if (!--p->used)
1260                 if (unlikely(p->unregistering))
1261                         complete(p->unregistering);
1262 }
1263
1264 /* called under sysctl_lock, will reacquire if has to wait */
1265 static void start_unregistering(struct ctl_table_header *p)
1266 {
1267         /*
1268          * if p->used is 0, nobody will ever touch that entry again;
1269          * we'll eliminate all paths to it before dropping sysctl_lock
1270          */
1271         if (unlikely(p->used)) {
1272                 struct completion wait;
1273                 init_completion(&wait);
1274                 p->unregistering = &wait;
1275                 spin_unlock(&sysctl_lock);
1276                 wait_for_completion(&wait);
1277                 spin_lock(&sysctl_lock);
1278         }
1279         /*
1280          * do not remove from the list until nobody holds it; walking the
1281          * list in do_sysctl() relies on that.
1282          */
1283         list_del_init(&p->ctl_entry);
1284 }
1285
1286 void sysctl_head_finish(struct ctl_table_header *head)
1287 {
1288         if (!head)
1289                 return;
1290         spin_lock(&sysctl_lock);
1291         unuse_table(head);
1292         spin_unlock(&sysctl_lock);
1293 }
1294
1295 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1296 {
1297         struct ctl_table_header *head;
1298         struct list_head *tmp;
1299         spin_lock(&sysctl_lock);
1300         if (prev) {
1301                 tmp = &prev->ctl_entry;
1302                 unuse_table(prev);
1303                 goto next;
1304         }
1305         tmp = &root_table_header.ctl_entry;
1306         for (;;) {
1307                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1308
1309                 if (!use_table(head))
1310                         goto next;
1311                 spin_unlock(&sysctl_lock);
1312                 return head;
1313         next:
1314                 tmp = tmp->next;
1315                 if (tmp == &root_table_header.ctl_entry)
1316                         break;
1317         }
1318         spin_unlock(&sysctl_lock);
1319         return NULL;
1320 }
1321
1322 #ifdef CONFIG_SYSCTL_SYSCALL
1323 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1324                void __user *newval, size_t newlen)
1325 {
1326         struct ctl_table_header *head;
1327         int error = -ENOTDIR;
1328
1329         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1330                 return -ENOTDIR;
1331         if (oldval) {
1332                 int old_len;
1333                 if (!oldlenp || get_user(old_len, oldlenp))
1334                         return -EFAULT;
1335         }
1336
1337         for (head = sysctl_head_next(NULL); head;
1338                         head = sysctl_head_next(head)) {
1339                 error = parse_table(name, nlen, oldval, oldlenp,
1340                                         newval, newlen, head->ctl_table);
1341                 if (error != -ENOTDIR) {
1342                         sysctl_head_finish(head);
1343                         break;
1344                 }
1345         }
1346         return error;
1347 }
1348
1349 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1350 {
1351         struct __sysctl_args tmp;
1352         int error;
1353
1354         if (copy_from_user(&tmp, args, sizeof(tmp)))
1355                 return -EFAULT;
1356
1357         error = deprecated_sysctl_warning(&tmp);
1358         if (error)
1359                 goto out;
1360
1361         lock_kernel();
1362         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1363                           tmp.newval, tmp.newlen);
1364         unlock_kernel();
1365 out:
1366         return error;
1367 }
1368 #endif /* CONFIG_SYSCTL_SYSCALL */
1369
1370 /*
1371  * sysctl_perm does NOT grant the superuser all rights automatically, because
1372  * some sysctl variables are readonly even to root.
1373  */
1374
1375 static int test_perm(int mode, int op)
1376 {
1377         if (!current->euid)
1378                 mode >>= 6;
1379         else if (in_egroup_p(0))
1380                 mode >>= 3;
1381         if ((mode & op & 0007) == op)
1382                 return 0;
1383         return -EACCES;
1384 }
1385
1386 int sysctl_perm(struct ctl_table *table, int op)
1387 {
1388         int error;
1389         error = security_sysctl(table, op);
1390         if (error)
1391                 return error;
1392         return test_perm(table->mode, op);
1393 }
1394
1395 #ifdef CONFIG_SYSCTL_SYSCALL
1396 static int parse_table(int __user *name, int nlen,
1397                        void __user *oldval, size_t __user *oldlenp,
1398                        void __user *newval, size_t newlen,
1399                        struct ctl_table *table)
1400 {
1401         int n;
1402 repeat:
1403         if (!nlen)
1404                 return -ENOTDIR;
1405         if (get_user(n, name))
1406                 return -EFAULT;
1407         for ( ; table->ctl_name || table->procname; table++) {
1408                 if (!table->ctl_name)
1409                         continue;
1410                 if (n == table->ctl_name) {
1411                         int error;
1412                         if (table->child) {
1413                                 if (sysctl_perm(table, 001))
1414                                         return -EPERM;
1415                                 name++;
1416                                 nlen--;
1417                                 table = table->child;
1418                                 goto repeat;
1419                         }
1420                         error = do_sysctl_strategy(table, name, nlen,
1421                                                    oldval, oldlenp,
1422                                                    newval, newlen);
1423                         return error;
1424                 }
1425         }
1426         return -ENOTDIR;
1427 }
1428
1429 /* Perform the actual read/write of a sysctl table entry. */
1430 int do_sysctl_strategy (struct ctl_table *table,
1431                         int __user *name, int nlen,
1432                         void __user *oldval, size_t __user *oldlenp,
1433                         void __user *newval, size_t newlen)
1434 {
1435         int op = 0, rc;
1436
1437         if (oldval)
1438                 op |= 004;
1439         if (newval)
1440                 op |= 002;
1441         if (sysctl_perm(table, op))
1442                 return -EPERM;
1443
1444         if (table->strategy) {
1445                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1446                                      newval, newlen);
1447                 if (rc < 0)
1448                         return rc;
1449                 if (rc > 0)
1450                         return 0;
1451         }
1452
1453         /* If there is no strategy routine, or if the strategy returns
1454          * zero, proceed with automatic r/w */
1455         if (table->data && table->maxlen) {
1456                 rc = sysctl_data(table, name, nlen, oldval, oldlenp,
1457                                  newval, newlen);
1458                 if (rc < 0)
1459                         return rc;
1460         }
1461         return 0;
1462 }
1463 #endif /* CONFIG_SYSCTL_SYSCALL */
1464
1465 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1466 {
1467         for (; table->ctl_name || table->procname; table++) {
1468                 table->parent = parent;
1469                 if (table->child)
1470                         sysctl_set_parent(table, table->child);
1471         }
1472 }
1473
1474 static __init int sysctl_init(void)
1475 {
1476         int err;
1477         sysctl_set_parent(NULL, root_table);
1478         err = sysctl_check_table(root_table);
1479         return 0;
1480 }
1481
1482 core_initcall(sysctl_init);
1483
1484 /**
1485  * register_sysctl_table - register a sysctl hierarchy
1486  * @table: the top-level table structure
1487  *
1488  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1489  * array. An entry with a ctl_name of 0 terminates the table.
1490  *
1491  * The members of the &struct ctl_table structure are used as follows:
1492  *
1493  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1494  *            must be unique within that level of sysctl
1495  *
1496  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1497  *            enter a sysctl file
1498  *
1499  * data - a pointer to data for use by proc_handler
1500  *
1501  * maxlen - the maximum size in bytes of the data
1502  *
1503  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1504  *
1505  * child - a pointer to the child sysctl table if this entry is a directory, or
1506  *         %NULL.
1507  *
1508  * proc_handler - the text handler routine (described below)
1509  *
1510  * strategy - the strategy routine (described below)
1511  *
1512  * de - for internal use by the sysctl routines
1513  *
1514  * extra1, extra2 - extra pointers usable by the proc handler routines
1515  *
1516  * Leaf nodes in the sysctl tree will be represented by a single file
1517  * under /proc; non-leaf nodes will be represented by directories.
1518  *
1519  * sysctl(2) can automatically manage read and write requests through
1520  * the sysctl table.  The data and maxlen fields of the ctl_table
1521  * struct enable minimal validation of the values being written to be
1522  * performed, and the mode field allows minimal authentication.
1523  *
1524  * More sophisticated management can be enabled by the provision of a
1525  * strategy routine with the table entry.  This will be called before
1526  * any automatic read or write of the data is performed.
1527  *
1528  * The strategy routine may return
1529  *
1530  * < 0 - Error occurred (error is passed to user process)
1531  *
1532  * 0   - OK - proceed with automatic read or write.
1533  *
1534  * > 0 - OK - read or write has been done by the strategy routine, so
1535  *       return immediately.
1536  *
1537  * There must be a proc_handler routine for any terminal nodes
1538  * mirrored under /proc/sys (non-terminals are handled by a built-in
1539  * directory handler).  Several default handlers are available to
1540  * cover common cases -
1541  *
1542  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1543  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1544  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1545  *
1546  * It is the handler's job to read the input buffer from user memory
1547  * and process it. The handler should return 0 on success.
1548  *
1549  * This routine returns %NULL on a failure to register, and a pointer
1550  * to the table header on success.
1551  */
1552 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1553 {
1554         struct ctl_table_header *tmp;
1555         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1556         if (!tmp)
1557                 return NULL;
1558         tmp->ctl_table = table;
1559         INIT_LIST_HEAD(&tmp->ctl_entry);
1560         tmp->used = 0;
1561         tmp->unregistering = NULL;
1562         sysctl_set_parent(NULL, table);
1563         if (sysctl_check_table(tmp->ctl_table)) {
1564                 kfree(tmp);
1565                 return NULL;
1566         }
1567         spin_lock(&sysctl_lock);
1568         list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1569         spin_unlock(&sysctl_lock);
1570         return tmp;
1571 }
1572
1573 /**
1574  * unregister_sysctl_table - unregister a sysctl table hierarchy
1575  * @header: the header returned from register_sysctl_table
1576  *
1577  * Unregisters the sysctl table and all children. proc entries may not
1578  * actually be removed until they are no longer used by anyone.
1579  */
1580 void unregister_sysctl_table(struct ctl_table_header * header)
1581 {
1582         might_sleep();
1583         spin_lock(&sysctl_lock);
1584         start_unregistering(header);
1585         spin_unlock(&sysctl_lock);
1586         kfree(header);
1587 }
1588
1589 #else /* !CONFIG_SYSCTL */
1590 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1591 {
1592         return NULL;
1593 }
1594
1595 void unregister_sysctl_table(struct ctl_table_header * table)
1596 {
1597 }
1598
1599 #endif /* CONFIG_SYSCTL */
1600
1601 /*
1602  * /proc/sys support
1603  */
1604
1605 #ifdef CONFIG_PROC_SYSCTL
1606
1607 static int _proc_do_string(void* data, int maxlen, int write,
1608                            struct file *filp, void __user *buffer,
1609                            size_t *lenp, loff_t *ppos)
1610 {
1611         size_t len;
1612         char __user *p;
1613         char c;
1614
1615         if (!data || !maxlen || !*lenp) {
1616                 *lenp = 0;
1617                 return 0;
1618         }
1619
1620         if (write) {
1621                 len = 0;
1622                 p = buffer;
1623                 while (len < *lenp) {
1624                         if (get_user(c, p++))
1625                                 return -EFAULT;
1626                         if (c == 0 || c == '\n')
1627                                 break;
1628                         len++;
1629                 }
1630                 if (len >= maxlen)
1631                         len = maxlen-1;
1632                 if(copy_from_user(data, buffer, len))
1633                         return -EFAULT;
1634                 ((char *) data)[len] = 0;
1635                 *ppos += *lenp;
1636         } else {
1637                 len = strlen(data);
1638                 if (len > maxlen)
1639                         len = maxlen;
1640
1641                 if (*ppos > len) {
1642                         *lenp = 0;
1643                         return 0;
1644                 }
1645
1646                 data += *ppos;
1647                 len  -= *ppos;
1648
1649                 if (len > *lenp)
1650                         len = *lenp;
1651                 if (len)
1652                         if(copy_to_user(buffer, data, len))
1653                                 return -EFAULT;
1654                 if (len < *lenp) {
1655                         if(put_user('\n', ((char __user *) buffer) + len))
1656                                 return -EFAULT;
1657                         len++;
1658                 }
1659                 *lenp = len;
1660                 *ppos += len;
1661         }
1662         return 0;
1663 }
1664
1665 /**
1666  * proc_dostring - read a string sysctl
1667  * @table: the sysctl table
1668  * @write: %TRUE if this is a write to the sysctl file
1669  * @filp: the file structure
1670  * @buffer: the user buffer
1671  * @lenp: the size of the user buffer
1672  * @ppos: file position
1673  *
1674  * Reads/writes a string from/to the user buffer. If the kernel
1675  * buffer provided is not large enough to hold the string, the
1676  * string is truncated. The copied string is %NULL-terminated.
1677  * If the string is being read by the user process, it is copied
1678  * and a newline '\n' is added. It is truncated if the buffer is
1679  * not large enough.
1680  *
1681  * Returns 0 on success.
1682  */
1683 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
1684                   void __user *buffer, size_t *lenp, loff_t *ppos)
1685 {
1686         return _proc_do_string(table->data, table->maxlen, write, filp,
1687                                buffer, lenp, ppos);
1688 }
1689
1690
1691 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1692                                  int *valp,
1693                                  int write, void *data)
1694 {
1695         if (write) {
1696                 *valp = *negp ? -*lvalp : *lvalp;
1697         } else {
1698                 int val = *valp;
1699                 if (val < 0) {
1700                         *negp = -1;
1701                         *lvalp = (unsigned long)-val;
1702                 } else {
1703                         *negp = 0;
1704                         *lvalp = (unsigned long)val;
1705                 }
1706         }
1707         return 0;
1708 }
1709
1710 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
1711                   int write, struct file *filp, void __user *buffer,
1712                   size_t *lenp, loff_t *ppos,
1713                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1714                               int write, void *data),
1715                   void *data)
1716 {
1717 #define TMPBUFLEN 21
1718         int *i, vleft, first=1, neg, val;
1719         unsigned long lval;
1720         size_t left, len;
1721
1722         char buf[TMPBUFLEN], *p;
1723         char __user *s = buffer;
1724
1725         if (!tbl_data || !table->maxlen || !*lenp ||
1726             (*ppos && !write)) {
1727                 *lenp = 0;
1728                 return 0;
1729         }
1730
1731         i = (int *) tbl_data;
1732         vleft = table->maxlen / sizeof(*i);
1733         left = *lenp;
1734
1735         if (!conv)
1736                 conv = do_proc_dointvec_conv;
1737
1738         for (; left && vleft--; i++, first=0) {
1739                 if (write) {
1740                         while (left) {
1741                                 char c;
1742                                 if (get_user(c, s))
1743                                         return -EFAULT;
1744                                 if (!isspace(c))
1745                                         break;
1746                                 left--;
1747                                 s++;
1748                         }
1749                         if (!left)
1750                                 break;
1751                         neg = 0;
1752                         len = left;
1753                         if (len > sizeof(buf) - 1)
1754                                 len = sizeof(buf) - 1;
1755                         if (copy_from_user(buf, s, len))
1756                                 return -EFAULT;
1757                         buf[len] = 0;
1758                         p = buf;
1759                         if (*p == '-' && left > 1) {
1760                                 neg = 1;
1761                                 p++;
1762                         }
1763                         if (*p < '0' || *p > '9')
1764                                 break;
1765
1766                         lval = simple_strtoul(p, &p, 0);
1767
1768                         len = p-buf;
1769                         if ((len < left) && *p && !isspace(*p))
1770                                 break;
1771                         if (neg)
1772                                 val = -val;
1773                         s += len;
1774                         left -= len;
1775
1776                         if (conv(&neg, &lval, i, 1, data))
1777                                 break;
1778                 } else {
1779                         p = buf;
1780                         if (!first)
1781                                 *p++ = '\t';
1782
1783                         if (conv(&neg, &lval, i, 0, data))
1784                                 break;
1785
1786                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1787                         len = strlen(buf);
1788                         if (len > left)
1789                                 len = left;
1790                         if(copy_to_user(s, buf, len))
1791                                 return -EFAULT;
1792                         left -= len;
1793                         s += len;
1794                 }
1795         }
1796
1797         if (!write && !first && left) {
1798                 if(put_user('\n', s))
1799                         return -EFAULT;
1800                 left--, s++;
1801         }
1802         if (write) {
1803                 while (left) {
1804                         char c;
1805                         if (get_user(c, s++))
1806                                 return -EFAULT;
1807                         if (!isspace(c))
1808                                 break;
1809                         left--;
1810                 }
1811         }
1812         if (write && first)
1813                 return -EINVAL;
1814         *lenp -= left;
1815         *ppos += *lenp;
1816         return 0;
1817 #undef TMPBUFLEN
1818 }
1819
1820 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
1821                   void __user *buffer, size_t *lenp, loff_t *ppos,
1822                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1823                               int write, void *data),
1824                   void *data)
1825 {
1826         return __do_proc_dointvec(table->data, table, write, filp,
1827                         buffer, lenp, ppos, conv, data);
1828 }
1829
1830 /**
1831  * proc_dointvec - read a vector of integers
1832  * @table: the sysctl table
1833  * @write: %TRUE if this is a write to the sysctl file
1834  * @filp: the file structure
1835  * @buffer: the user buffer
1836  * @lenp: the size of the user buffer
1837  * @ppos: file position
1838  *
1839  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1840  * values from/to the user buffer, treated as an ASCII string.
1841  *
1842  * Returns 0 on success.
1843  */
1844 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
1845                      void __user *buffer, size_t *lenp, loff_t *ppos)
1846 {
1847     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1848                             NULL,NULL);
1849 }
1850
1851 #define OP_SET  0
1852 #define OP_AND  1
1853 #define OP_OR   2
1854
1855 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1856                                       int *valp,
1857                                       int write, void *data)
1858 {
1859         int op = *(int *)data;
1860         if (write) {
1861                 int val = *negp ? -*lvalp : *lvalp;
1862                 switch(op) {
1863                 case OP_SET:    *valp = val; break;
1864                 case OP_AND:    *valp &= val; break;
1865                 case OP_OR:     *valp |= val; break;
1866                 }
1867         } else {
1868                 int val = *valp;
1869                 if (val < 0) {
1870                         *negp = -1;
1871                         *lvalp = (unsigned long)-val;
1872                 } else {
1873                         *negp = 0;
1874                         *lvalp = (unsigned long)val;
1875                 }
1876         }
1877         return 0;
1878 }
1879
1880 #ifdef CONFIG_SECURITY_CAPABILITIES
1881 /*
1882  *      init may raise the set.
1883  */
1884
1885 int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp,
1886                         void __user *buffer, size_t *lenp, loff_t *ppos)
1887 {
1888         int op;
1889
1890         if (write && !capable(CAP_SYS_MODULE)) {
1891                 return -EPERM;
1892         }
1893
1894         op = is_global_init(current) ? OP_SET : OP_AND;
1895         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1896                                 do_proc_dointvec_bset_conv,&op);
1897 }
1898 #endif /* def CONFIG_SECURITY_CAPABILITIES */
1899
1900 /*
1901  *      Taint values can only be increased
1902  */
1903 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
1904                                void __user *buffer, size_t *lenp, loff_t *ppos)
1905 {
1906         int op;
1907
1908         if (write && !capable(CAP_SYS_ADMIN))
1909                 return -EPERM;
1910
1911         op = OP_OR;
1912         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1913                                 do_proc_dointvec_bset_conv,&op);
1914 }
1915
1916 struct do_proc_dointvec_minmax_conv_param {
1917         int *min;
1918         int *max;
1919 };
1920
1921 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1922                                         int *valp,
1923                                         int write, void *data)
1924 {
1925         struct do_proc_dointvec_minmax_conv_param *param = data;
1926         if (write) {
1927                 int val = *negp ? -*lvalp : *lvalp;
1928                 if ((param->min && *param->min > val) ||
1929                     (param->max && *param->max < val))
1930                         return -EINVAL;
1931                 *valp = val;
1932         } else {
1933                 int val = *valp;
1934                 if (val < 0) {
1935                         *negp = -1;
1936                         *lvalp = (unsigned long)-val;
1937                 } else {
1938                         *negp = 0;
1939                         *lvalp = (unsigned long)val;
1940                 }
1941         }
1942         return 0;
1943 }
1944
1945 /**
1946  * proc_dointvec_minmax - read a vector of integers with min/max values
1947  * @table: the sysctl table
1948  * @write: %TRUE if this is a write to the sysctl file
1949  * @filp: the file structure
1950  * @buffer: the user buffer
1951  * @lenp: the size of the user buffer
1952  * @ppos: file position
1953  *
1954  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1955  * values from/to the user buffer, treated as an ASCII string.
1956  *
1957  * This routine will ensure the values are within the range specified by
1958  * table->extra1 (min) and table->extra2 (max).
1959  *
1960  * Returns 0 on success.
1961  */
1962 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
1963                   void __user *buffer, size_t *lenp, loff_t *ppos)
1964 {
1965         struct do_proc_dointvec_minmax_conv_param param = {
1966                 .min = (int *) table->extra1,
1967                 .max = (int *) table->extra2,
1968         };
1969         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1970                                 do_proc_dointvec_minmax_conv, &param);
1971 }
1972
1973 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
1974                                      struct file *filp,
1975                                      void __user *buffer,
1976                                      size_t *lenp, loff_t *ppos,
1977                                      unsigned long convmul,
1978                                      unsigned long convdiv)
1979 {
1980 #define TMPBUFLEN 21
1981         unsigned long *i, *min, *max, val;
1982         int vleft, first=1, neg;
1983         size_t len, left;
1984         char buf[TMPBUFLEN], *p;
1985         char __user *s = buffer;
1986
1987         if (!data || !table->maxlen || !*lenp ||
1988             (*ppos && !write)) {
1989                 *lenp = 0;
1990                 return 0;
1991         }
1992
1993         i = (unsigned long *) data;
1994         min = (unsigned long *) table->extra1;
1995         max = (unsigned long *) table->extra2;
1996         vleft = table->maxlen / sizeof(unsigned long);
1997         left = *lenp;
1998
1999         for (; left && vleft--; i++, min++, max++, first=0) {
2000                 if (write) {
2001                         while (left) {
2002                                 char c;
2003                                 if (get_user(c, s))
2004                                         return -EFAULT;
2005                                 if (!isspace(c))
2006                                         break;
2007                                 left--;
2008                                 s++;
2009                         }
2010                         if (!left)
2011                                 break;
2012                         neg = 0;
2013                         len = left;
2014                         if (len > TMPBUFLEN-1)
2015                                 len = TMPBUFLEN-1;
2016                         if (copy_from_user(buf, s, len))
2017                                 return -EFAULT;
2018                         buf[len] = 0;
2019                         p = buf;
2020                         if (*p == '-' && left > 1) {
2021                                 neg = 1;
2022                                 p++;
2023                         }
2024                         if (*p < '0' || *p > '9')
2025                                 break;
2026                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2027                         len = p-buf;
2028                         if ((len < left) && *p && !isspace(*p))
2029                                 break;
2030                         if (neg)
2031                                 val = -val;
2032                         s += len;
2033                         left -= len;
2034
2035                         if(neg)
2036                                 continue;
2037                         if ((min && val < *min) || (max && val > *max))
2038                                 continue;
2039                         *i = val;
2040                 } else {
2041                         p = buf;
2042                         if (!first)
2043                                 *p++ = '\t';
2044                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2045                         len = strlen(buf);
2046                         if (len > left)
2047                                 len = left;
2048                         if(copy_to_user(s, buf, len))
2049                                 return -EFAULT;
2050                         left -= len;
2051                         s += len;
2052                 }
2053         }
2054
2055         if (!write && !first && left) {
2056                 if(put_user('\n', s))
2057                         return -EFAULT;
2058                 left--, s++;
2059         }
2060         if (write) {
2061                 while (left) {
2062                         char c;
2063                         if (get_user(c, s++))
2064                                 return -EFAULT;
2065                         if (!isspace(c))
2066                                 break;
2067                         left--;
2068                 }
2069         }
2070         if (write && first)
2071                 return -EINVAL;
2072         *lenp -= left;
2073         *ppos += *lenp;
2074         return 0;
2075 #undef TMPBUFLEN
2076 }
2077
2078 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2079                                      struct file *filp,
2080                                      void __user *buffer,
2081                                      size_t *lenp, loff_t *ppos,
2082                                      unsigned long convmul,
2083                                      unsigned long convdiv)
2084 {
2085         return __do_proc_doulongvec_minmax(table->data, table, write,
2086                         filp, buffer, lenp, ppos, convmul, convdiv);
2087 }
2088
2089 /**
2090  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2091  * @table: the sysctl table
2092  * @write: %TRUE if this is a write to the sysctl file
2093  * @filp: the file structure
2094  * @buffer: the user buffer
2095  * @lenp: the size of the user buffer
2096  * @ppos: file position
2097  *
2098  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2099  * values from/to the user buffer, treated as an ASCII string.
2100  *
2101  * This routine will ensure the values are within the range specified by
2102  * table->extra1 (min) and table->extra2 (max).
2103  *
2104  * Returns 0 on success.
2105  */
2106 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2107                            void __user *buffer, size_t *lenp, loff_t *ppos)
2108 {
2109     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2110 }
2111
2112 /**
2113  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2114  * @table: the sysctl table
2115  * @write: %TRUE if this is a write to the sysctl file
2116  * @filp: the file structure
2117  * @buffer: the user buffer
2118  * @lenp: the size of the user buffer
2119  * @ppos: file position
2120  *
2121  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2122  * values from/to the user buffer, treated as an ASCII string. The values
2123  * are treated as milliseconds, and converted to jiffies when they are stored.
2124  *
2125  * This routine will ensure the values are within the range specified by
2126  * table->extra1 (min) and table->extra2 (max).
2127  *
2128  * Returns 0 on success.
2129  */
2130 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2131                                       struct file *filp,
2132                                       void __user *buffer,
2133                                       size_t *lenp, loff_t *ppos)
2134 {
2135     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2136                                      lenp, ppos, HZ, 1000l);
2137 }
2138
2139
2140 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2141                                          int *valp,
2142                                          int write, void *data)
2143 {
2144         if (write) {
2145                 if (*lvalp > LONG_MAX / HZ)
2146                         return 1;
2147                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2148         } else {
2149                 int val = *valp;
2150                 unsigned long lval;
2151                 if (val < 0) {
2152                         *negp = -1;
2153                         lval = (unsigned long)-val;
2154                 } else {
2155                         *negp = 0;
2156                         lval = (unsigned long)val;
2157                 }
2158                 *lvalp = lval / HZ;
2159         }
2160         return 0;
2161 }
2162
2163 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2164                                                 int *valp,
2165                                                 int write, void *data)
2166 {
2167         if (write) {
2168                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2169                         return 1;
2170                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2171         } else {
2172                 int val = *valp;
2173                 unsigned long lval;
2174                 if (val < 0) {
2175                         *negp = -1;
2176                         lval = (unsigned long)-val;
2177                 } else {
2178                         *negp = 0;
2179                         lval = (unsigned long)val;
2180                 }
2181                 *lvalp = jiffies_to_clock_t(lval);
2182         }
2183         return 0;
2184 }
2185
2186 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2187                                             int *valp,
2188                                             int write, void *data)
2189 {
2190         if (write) {
2191                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2192         } else {
2193                 int val = *valp;
2194                 unsigned long lval;
2195                 if (val < 0) {
2196                         *negp = -1;
2197                         lval = (unsigned long)-val;
2198                 } else {
2199                         *negp = 0;
2200                         lval = (unsigned long)val;
2201                 }
2202                 *lvalp = jiffies_to_msecs(lval);
2203         }
2204         return 0;
2205 }
2206
2207 /**
2208  * proc_dointvec_jiffies - read a vector of integers as seconds
2209  * @table: the sysctl table
2210  * @write: %TRUE if this is a write to the sysctl file
2211  * @filp: the file structure
2212  * @buffer: the user buffer
2213  * @lenp: the size of the user buffer
2214  * @ppos: file position
2215  *
2216  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2217  * values from/to the user buffer, treated as an ASCII string.
2218  * The values read are assumed to be in seconds, and are converted into
2219  * jiffies.
2220  *
2221  * Returns 0 on success.
2222  */
2223 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2224                           void __user *buffer, size_t *lenp, loff_t *ppos)
2225 {
2226     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2227                             do_proc_dointvec_jiffies_conv,NULL);
2228 }
2229
2230 /**
2231  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2232  * @table: the sysctl table
2233  * @write: %TRUE if this is a write to the sysctl file
2234  * @filp: the file structure
2235  * @buffer: the user buffer
2236  * @lenp: the size of the user buffer
2237  * @ppos: pointer to the file position
2238  *
2239  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2240  * values from/to the user buffer, treated as an ASCII string.
2241  * The values read are assumed to be in 1/USER_HZ seconds, and
2242  * are converted into jiffies.
2243  *
2244  * Returns 0 on success.
2245  */
2246 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2247                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2248 {
2249     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2250                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2251 }
2252
2253 /**
2254  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2255  * @table: the sysctl table
2256  * @write: %TRUE if this is a write to the sysctl file
2257  * @filp: the file structure
2258  * @buffer: the user buffer
2259  * @lenp: the size of the user buffer
2260  * @ppos: file position
2261  * @ppos: the current position in the file
2262  *
2263  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2264  * values from/to the user buffer, treated as an ASCII string.
2265  * The values read are assumed to be in 1/1000 seconds, and
2266  * are converted into jiffies.
2267  *
2268  * Returns 0 on success.
2269  */
2270 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2271                              void __user *buffer, size_t *lenp, loff_t *ppos)
2272 {
2273         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2274                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2275 }
2276
2277 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2278                            void __user *buffer, size_t *lenp, loff_t *ppos)
2279 {
2280         struct pid *new_pid;
2281         pid_t tmp;
2282         int r;
2283
2284         tmp = pid_nr_ns(cad_pid, current->nsproxy->pid_ns);
2285
2286         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2287                                lenp, ppos, NULL, NULL);
2288         if (r || !write)
2289                 return r;
2290
2291         new_pid = find_get_pid(tmp);
2292         if (!new_pid)
2293                 return -ESRCH;
2294
2295         put_pid(xchg(&cad_pid, new_pid));
2296         return 0;
2297 }
2298
2299 #else /* CONFIG_PROC_FS */
2300
2301 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2302                   void __user *buffer, size_t *lenp, loff_t *ppos)
2303 {
2304         return -ENOSYS;
2305 }
2306
2307 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2308                   void __user *buffer, size_t *lenp, loff_t *ppos)
2309 {
2310         return -ENOSYS;
2311 }
2312
2313 int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp,
2314                         void __user *buffer, size_t *lenp, loff_t *ppos)
2315 {
2316         return -ENOSYS;
2317 }
2318
2319 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2320                     void __user *buffer, size_t *lenp, loff_t *ppos)
2321 {
2322         return -ENOSYS;
2323 }
2324
2325 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2326                     void __user *buffer, size_t *lenp, loff_t *ppos)
2327 {
2328         return -ENOSYS;
2329 }
2330
2331 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2332                     void __user *buffer, size_t *lenp, loff_t *ppos)
2333 {
2334         return -ENOSYS;
2335 }
2336
2337 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2338                              void __user *buffer, size_t *lenp, loff_t *ppos)
2339 {
2340         return -ENOSYS;
2341 }
2342
2343 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2344                     void __user *buffer, size_t *lenp, loff_t *ppos)
2345 {
2346         return -ENOSYS;
2347 }
2348
2349 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2350                                       struct file *filp,
2351                                       void __user *buffer,
2352                                       size_t *lenp, loff_t *ppos)
2353 {
2354     return -ENOSYS;
2355 }
2356
2357
2358 #endif /* CONFIG_PROC_FS */
2359
2360
2361 #ifdef CONFIG_SYSCTL_SYSCALL
2362 /*
2363  * General sysctl support routines
2364  */
2365
2366 /* The generic sysctl data routine (used if no strategy routine supplied) */
2367 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2368                 void __user *oldval, size_t __user *oldlenp,
2369                 void __user *newval, size_t newlen)
2370 {
2371         size_t len;
2372
2373         /* Get out of I don't have a variable */
2374         if (!table->data || !table->maxlen)
2375                 return -ENOTDIR;
2376
2377         if (oldval && oldlenp) {
2378                 if (get_user(len, oldlenp))
2379                         return -EFAULT;
2380                 if (len) {
2381                         if (len > table->maxlen)
2382                                 len = table->maxlen;
2383                         if (copy_to_user(oldval, table->data, len))
2384                                 return -EFAULT;
2385                         if (put_user(len, oldlenp))
2386                                 return -EFAULT;
2387                 }
2388         }
2389
2390         if (newval && newlen) {
2391                 if (newlen > table->maxlen)
2392                         newlen = table->maxlen;
2393
2394                 if (copy_from_user(table->data, newval, newlen))
2395                         return -EFAULT;
2396         }
2397         return 1;
2398 }
2399
2400 /* The generic string strategy routine: */
2401 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2402                   void __user *oldval, size_t __user *oldlenp,
2403                   void __user *newval, size_t newlen)
2404 {
2405         if (!table->data || !table->maxlen)
2406                 return -ENOTDIR;
2407
2408         if (oldval && oldlenp) {
2409                 size_t bufsize;
2410                 if (get_user(bufsize, oldlenp))
2411                         return -EFAULT;
2412                 if (bufsize) {
2413                         size_t len = strlen(table->data), copied;
2414
2415                         /* This shouldn't trigger for a well-formed sysctl */
2416                         if (len > table->maxlen)
2417                                 len = table->maxlen;
2418
2419                         /* Copy up to a max of bufsize-1 bytes of the string */
2420                         copied = (len >= bufsize) ? bufsize - 1 : len;
2421
2422                         if (copy_to_user(oldval, table->data, copied) ||
2423                             put_user(0, (char __user *)(oldval + copied)))
2424                                 return -EFAULT;
2425                         if (put_user(len, oldlenp))
2426                                 return -EFAULT;
2427                 }
2428         }
2429         if (newval && newlen) {
2430                 size_t len = newlen;
2431                 if (len > table->maxlen)
2432                         len = table->maxlen;
2433                 if(copy_from_user(table->data, newval, len))
2434                         return -EFAULT;
2435                 if (len == table->maxlen)
2436                         len--;
2437                 ((char *) table->data)[len] = 0;
2438         }
2439         return 1;
2440 }
2441
2442 /*
2443  * This function makes sure that all of the integers in the vector
2444  * are between the minimum and maximum values given in the arrays
2445  * table->extra1 and table->extra2, respectively.
2446  */
2447 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2448                 void __user *oldval, size_t __user *oldlenp,
2449                 void __user *newval, size_t newlen)
2450 {
2451
2452         if (newval && newlen) {
2453                 int __user *vec = (int __user *) newval;
2454                 int *min = (int *) table->extra1;
2455                 int *max = (int *) table->extra2;
2456                 size_t length;
2457                 int i;
2458
2459                 if (newlen % sizeof(int) != 0)
2460                         return -EINVAL;
2461
2462                 if (!table->extra1 && !table->extra2)
2463                         return 0;
2464
2465                 if (newlen > table->maxlen)
2466                         newlen = table->maxlen;
2467                 length = newlen / sizeof(int);
2468
2469                 for (i = 0; i < length; i++) {
2470                         int value;
2471                         if (get_user(value, vec + i))
2472                                 return -EFAULT;
2473                         if (min && value < min[i])
2474                                 return -EINVAL;
2475                         if (max && value > max[i])
2476                                 return -EINVAL;
2477                 }
2478         }
2479         return 0;
2480 }
2481
2482 /* Strategy function to convert jiffies to seconds */
2483 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2484                 void __user *oldval, size_t __user *oldlenp,
2485                 void __user *newval, size_t newlen)
2486 {
2487         if (oldval && oldlenp) {
2488                 size_t olen;
2489
2490                 if (get_user(olen, oldlenp))
2491                         return -EFAULT;
2492                 if (olen) {
2493                         int val;
2494
2495                         if (olen < sizeof(int))
2496                                 return -EINVAL;
2497
2498                         val = *(int *)(table->data) / HZ;
2499                         if (put_user(val, (int __user *)oldval))
2500                                 return -EFAULT;
2501                         if (put_user(sizeof(int), oldlenp))
2502                                 return -EFAULT;
2503                 }
2504         }
2505         if (newval && newlen) {
2506                 int new;
2507                 if (newlen != sizeof(int))
2508                         return -EINVAL;
2509                 if (get_user(new, (int __user *)newval))
2510                         return -EFAULT;
2511                 *(int *)(table->data) = new*HZ;
2512         }
2513         return 1;
2514 }
2515
2516 /* Strategy function to convert jiffies to seconds */
2517 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2518                 void __user *oldval, size_t __user *oldlenp,
2519                 void __user *newval, size_t newlen)
2520 {
2521         if (oldval && oldlenp) {
2522                 size_t olen;
2523
2524                 if (get_user(olen, oldlenp))
2525                         return -EFAULT;
2526                 if (olen) {
2527                         int val;
2528
2529                         if (olen < sizeof(int))
2530                                 return -EINVAL;
2531
2532                         val = jiffies_to_msecs(*(int *)(table->data));
2533                         if (put_user(val, (int __user *)oldval))
2534                                 return -EFAULT;
2535                         if (put_user(sizeof(int), oldlenp))
2536                                 return -EFAULT;
2537                 }
2538         }
2539         if (newval && newlen) {
2540                 int new;
2541                 if (newlen != sizeof(int))
2542                         return -EINVAL;
2543                 if (get_user(new, (int __user *)newval))
2544                         return -EFAULT;
2545                 *(int *)(table->data) = msecs_to_jiffies(new);
2546         }
2547         return 1;
2548 }
2549
2550
2551
2552 #else /* CONFIG_SYSCTL_SYSCALL */
2553
2554
2555 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2556 {
2557         struct __sysctl_args tmp;
2558         int error;
2559
2560         if (copy_from_user(&tmp, args, sizeof(tmp)))
2561                 return -EFAULT;
2562
2563         error = deprecated_sysctl_warning(&tmp);
2564
2565         /* If no error reading the parameters then just -ENOSYS ... */
2566         if (!error)
2567                 error = -ENOSYS;
2568
2569         return error;
2570 }
2571
2572 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2573                   void __user *oldval, size_t __user *oldlenp,
2574                   void __user *newval, size_t newlen)
2575 {
2576         return -ENOSYS;
2577 }
2578
2579 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2580                   void __user *oldval, size_t __user *oldlenp,
2581                   void __user *newval, size_t newlen)
2582 {
2583         return -ENOSYS;
2584 }
2585
2586 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2587                 void __user *oldval, size_t __user *oldlenp,
2588                 void __user *newval, size_t newlen)
2589 {
2590         return -ENOSYS;
2591 }
2592
2593 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2594                 void __user *oldval, size_t __user *oldlenp,
2595                 void __user *newval, size_t newlen)
2596 {
2597         return -ENOSYS;
2598 }
2599
2600 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2601                 void __user *oldval, size_t __user *oldlenp,
2602                 void __user *newval, size_t newlen)
2603 {
2604         return -ENOSYS;
2605 }
2606
2607 #endif /* CONFIG_SYSCTL_SYSCALL */
2608
2609 static int deprecated_sysctl_warning(struct __sysctl_args *args)
2610 {
2611         static int msg_count;
2612         int name[CTL_MAXNAME];
2613         int i;
2614
2615         /* Read in the sysctl name for better debug message logging */
2616         for (i = 0; i < args->nlen; i++)
2617                 if (get_user(name[i], args->name + i))
2618                         return -EFAULT;
2619
2620         /* Ignore accesses to kernel.version */
2621         if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2622                 return 0;
2623
2624         if (msg_count < 5) {
2625                 msg_count++;
2626                 printk(KERN_INFO
2627                         "warning: process `%s' used the deprecated sysctl "
2628                         "system call with ", current->comm);
2629                 for (i = 0; i < args->nlen; i++)
2630                         printk("%d.", name[i]);
2631                 printk("\n");
2632         }
2633         return 0;
2634 }
2635
2636 /*
2637  * No sense putting this after each symbol definition, twice,
2638  * exception granted :-)
2639  */
2640 EXPORT_SYMBOL(proc_dointvec);
2641 EXPORT_SYMBOL(proc_dointvec_jiffies);
2642 EXPORT_SYMBOL(proc_dointvec_minmax);
2643 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2644 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2645 EXPORT_SYMBOL(proc_dostring);
2646 EXPORT_SYMBOL(proc_doulongvec_minmax);
2647 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2648 EXPORT_SYMBOL(register_sysctl_table);
2649 EXPORT_SYMBOL(sysctl_intvec);
2650 EXPORT_SYMBOL(sysctl_jiffies);
2651 EXPORT_SYMBOL(sysctl_ms_jiffies);
2652 EXPORT_SYMBOL(sysctl_string);
2653 EXPORT_SYMBOL(sysctl_data);
2654 EXPORT_SYMBOL(unregister_sysctl_table);