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

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/mm.h>
  23 #include <linux/swap.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/security.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/kmemcheck.h>
  31 #include <linux/smp_lock.h>
  32 #include <linux/fs.h>
  33 #include <linux/init.h>
  34 #include <linux/kernel.h>
  35 #include <linux/kobject.h>
  36 #include <linux/net.h>
  37 #include <linux/sysrq.h>
  38 #include <linux/highuid.h>
  39 #include <linux/writeback.h>
  40 #include <linux/hugetlb.h>
  41 #include <linux/initrd.h>
  42 #include <linux/key.h>
  43 #include <linux/times.h>
  44 #include <linux/limits.h>
  45 #include <linux/dcache.h>
  46 #include <linux/syscalls.h>
  47 #include <linux/vmstat.h>
  48 #include <linux/nfs_fs.h>
  49 #include <linux/acpi.h>
  50 #include <linux/reboot.h>
  51 #include <linux/ftrace.h>
  52 #include <linux/slow-work.h>
  53 #include <linux/perf_counter.h>
  54
  55 #include <asm/uaccess.h>
  56 #include <asm/processor.h>
  57
  58 #ifdef CONFIG_X86
  59 #include <asm/nmi.h>
  60 #include <asm/stacktrace.h>
  61 #include <asm/io.h>
  62 #endif
  63
  64 static int deprecated_sysctl_warning(struct __sysctl_args *args);
  65
  66 #if defined(CONFIG_SYSCTL)
  67
  68 /* External variables not in a header file. */
  69 extern int C_A_D;
  70 extern int print_fatal_signals;
  71 extern int sysctl_overcommit_memory;
  72 extern int sysctl_overcommit_ratio;
  73 extern int sysctl_panic_on_oom;
  74 extern int sysctl_oom_kill_allocating_task;
  75 extern int sysctl_oom_dump_tasks;
  76 extern int max_threads;
  77 extern int core_uses_pid;
  78 extern int suid_dumpable;
  79 extern char core_pattern[];
  80 extern int pid_max;
  81 extern int min_free_kbytes;
  82 extern int pid_max_min, pid_max_max;
  83 extern int sysctl_drop_caches;
  84 extern int percpu_pagelist_fraction;
  85 extern int compat_log;
  86 extern int latencytop_enabled;
  87 extern int sysctl_nr_open_min, sysctl_nr_open_max;
  88 #ifndef CONFIG_MMU
  89 extern int sysctl_nr_trim_pages;
  90 #endif
  91 #ifdef CONFIG_RCU_TORTURE_TEST
  92 extern int rcutorture_runnable;
  93 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
  94
  95 /* Constants used for minimum and  maximum */
  96 #ifdef CONFIG_DETECT_SOFTLOCKUP
  97 static int sixty = 60;
  98 static int neg_one = -1;
  99 #endif
 100
 101 static int zero;
 102 static int __maybe_unused one = 1;
 103 static int __maybe_unused two = 2;
 104 static unsigned long one_ul = 1;
 105 static int one_hundred = 100;
 106
 107 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
 108 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
 109
 110 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 111 static int maxolduid = 65535;
 112 static int minolduid;
 113 static int min_percpu_pagelist_fract = 8;
 114
 115 static int ngroups_max = NGROUPS_MAX;
 116
 117 #ifdef CONFIG_MODULES
 118 extern char modprobe_path[];
 119 extern int modules_disabled;
 120 #endif
 121 #ifdef CONFIG_CHR_DEV_SG
 122 extern int sg_big_buff;
 123 #endif
 124
 125 #ifdef CONFIG_SPARC
 126 #include <asm/system.h>
 127 #endif
 128
 129 #ifdef CONFIG_SPARC64
 130 extern int sysctl_tsb_ratio;
 131 #endif
 132
 133 #ifdef __hppa__
 134 extern int pwrsw_enabled;
 135 extern int unaligned_enabled;
 136 #endif
 137
 138 #ifdef CONFIG_S390
 139 #ifdef CONFIG_MATHEMU
 140 extern int sysctl_ieee_emulation_warnings;
 141 #endif
 142 extern int sysctl_userprocess_debug;
 143 extern int spin_retry;
 144 #endif
 145
 146 #ifdef CONFIG_BSD_PROCESS_ACCT
 147 extern int acct_parm[];
 148 #endif
 149
 150 #ifdef CONFIG_IA64
 151 extern int no_unaligned_warning;
 152 extern int unaligned_dump_stack;
 153 #endif
 154
 155 #ifdef CONFIG_RT_MUTEXES
 156 extern int max_lock_depth;
 157 #endif
 158
 159 #ifdef CONFIG_PROC_SYSCTL
 160 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
 161                   void __user *buffer, size_t *lenp, loff_t *ppos);
 162 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
 163                                void __user *buffer, size_t *lenp, loff_t *ppos);
 164 #endif
 165
 166 static struct ctl_table root_table[];
 167 static struct ctl_table_root sysctl_table_root;
 168 static struct ctl_table_header root_table_header = {
 169         .count = 1,
 170         .ctl_table = root_table,
 171         .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
 172         .root = &sysctl_table_root,
 173         .set = &sysctl_table_root.default_set,
 174 };
 175 static struct ctl_table_root sysctl_table_root = {
 176         .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
 177         .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
 178 };
 179
 180 static struct ctl_table kern_table[];
 181 static struct ctl_table vm_table[];
 182 static struct ctl_table fs_table[];
 183 static struct ctl_table debug_table[];
 184 static struct ctl_table dev_table[];
 185 extern struct ctl_table random_table[];
 186 #ifdef CONFIG_INOTIFY_USER
 187 extern struct ctl_table inotify_table[];
 188 #endif
 189 #ifdef CONFIG_EPOLL
 190 extern struct ctl_table epoll_table[];
 191 #endif
 192
 193 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 194 int sysctl_legacy_va_layout;
 195 #endif
 196
 197 extern int prove_locking;
 198 extern int lock_stat;
 199
 200 /* The default sysctl tables: */
 201
 202 static struct ctl_table root_table[] = {
 203         {
 204                 .ctl_name       = CTL_KERN,
 205                 .procname       = "kernel",
 206                 .mode           = 0555,
 207                 .child          = kern_table,
 208         },
 209         {
 210                 .ctl_name       = CTL_VM,
 211                 .procname       = "vm",
 212                 .mode           = 0555,
 213                 .child          = vm_table,
 214         },
 215         {
 216                 .ctl_name       = CTL_FS,
 217                 .procname       = "fs",
 218                 .mode           = 0555,
 219                 .child          = fs_table,
 220         },
 221         {
 222                 .ctl_name       = CTL_DEBUG,
 223                 .procname       = "debug",
 224                 .mode           = 0555,
 225                 .child          = debug_table,
 226         },
 227         {
 228                 .ctl_name       = CTL_DEV,
 229                 .procname       = "dev",
 230                 .mode           = 0555,
 231                 .child          = dev_table,
 232         },
 233 /*
 234  * NOTE: do not add new entries to this table unless you have read
 235  * Documentation/sysctl/ctl_unnumbered.txt
 236  */
 237         { .ctl_name = 0 }
 238 };
 239
 240 #ifdef CONFIG_SCHED_DEBUG
 241 static int min_sched_granularity_ns = 100000;           /* 100 usecs */
 242 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
 243 static int min_wakeup_granularity_ns;                   /* 0 usecs */
 244 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
 245 #endif
 246
 247 static struct ctl_table kern_table[] = {
 248 #ifdef CONFIG_SCHED_DEBUG
 249         {
 250                 .ctl_name       = CTL_UNNUMBERED,
 251                 .procname       = "sched_min_granularity_ns",
 252                 .data           = &sysctl_sched_min_granularity,
 253                 .maxlen         = sizeof(unsigned int),
 254                 .mode           = 0644,
 255                 .proc_handler   = &sched_nr_latency_handler,
 256                 .strategy       = &sysctl_intvec,
 257                 .extra1         = &min_sched_granularity_ns,
 258                 .extra2         = &max_sched_granularity_ns,
 259         },
 260         {
 261                 .ctl_name       = CTL_UNNUMBERED,
 262                 .procname       = "sched_latency_ns",
 263                 .data           = &sysctl_sched_latency,
 264                 .maxlen         = sizeof(unsigned int),
 265                 .mode           = 0644,
 266                 .proc_handler   = &sched_nr_latency_handler,
 267                 .strategy       = &sysctl_intvec,
 268                 .extra1         = &min_sched_granularity_ns,
 269                 .extra2         = &max_sched_granularity_ns,
 270         },
 271         {
 272                 .ctl_name       = CTL_UNNUMBERED,
 273                 .procname       = "sched_wakeup_granularity_ns",
 274                 .data           = &sysctl_sched_wakeup_granularity,
 275                 .maxlen         = sizeof(unsigned int),
 276                 .mode           = 0644,
 277                 .proc_handler   = &proc_dointvec_minmax,
 278                 .strategy       = &sysctl_intvec,
 279                 .extra1         = &min_wakeup_granularity_ns,
 280                 .extra2         = &max_wakeup_granularity_ns,
 281         },
 282         {
 283                 .ctl_name       = CTL_UNNUMBERED,
 284                 .procname       = "sched_shares_ratelimit",
 285                 .data           = &sysctl_sched_shares_ratelimit,
 286                 .maxlen         = sizeof(unsigned int),
 287                 .mode           = 0644,
 288                 .proc_handler   = &proc_dointvec,
 289         },
 290         {
 291                 .ctl_name       = CTL_UNNUMBERED,
 292                 .procname       = "sched_shares_thresh",
 293                 .data           = &sysctl_sched_shares_thresh,
 294                 .maxlen         = sizeof(unsigned int),
 295                 .mode           = 0644,
 296                 .proc_handler   = &proc_dointvec_minmax,
 297                 .strategy       = &sysctl_intvec,
 298                 .extra1         = &zero,
 299         },
 300         {
 301                 .ctl_name       = CTL_UNNUMBERED,
 302                 .procname       = "sched_child_runs_first",
 303                 .data           = &sysctl_sched_child_runs_first,
 304                 .maxlen         = sizeof(unsigned int),
 305                 .mode           = 0644,
 306                 .proc_handler   = &proc_dointvec,
 307         },
 308         {
 309                 .ctl_name       = CTL_UNNUMBERED,
 310                 .procname       = "sched_features",
 311                 .data           = &sysctl_sched_features,
 312                 .maxlen         = sizeof(unsigned int),
 313                 .mode           = 0644,
 314                 .proc_handler   = &proc_dointvec,
 315         },
 316         {
 317                 .ctl_name       = CTL_UNNUMBERED,
 318                 .procname       = "sched_migration_cost",
 319                 .data           = &sysctl_sched_migration_cost,
 320                 .maxlen         = sizeof(unsigned int),
 321                 .mode           = 0644,
 322                 .proc_handler   = &proc_dointvec,
 323         },
 324         {
 325                 .ctl_name       = CTL_UNNUMBERED,
 326                 .procname       = "sched_nr_migrate",
 327                 .data           = &sysctl_sched_nr_migrate,
 328                 .maxlen         = sizeof(unsigned int),
 329                 .mode           = 0644,
 330                 .proc_handler   = &proc_dointvec,
 331         },
 332         {
 333                 .ctl_name       = CTL_UNNUMBERED,
 334                 .procname       = "timer_migration",
 335                 .data           = &sysctl_timer_migration,
 336                 .maxlen         = sizeof(unsigned int),
 337                 .mode           = 0644,
 338                 .proc_handler   = &proc_dointvec_minmax,
 339                 .strategy       = &sysctl_intvec,
 340                 .extra1         = &zero,
 341                 .extra2         = &one,
 342         },
 343 #endif
 344         {
 345                 .ctl_name       = CTL_UNNUMBERED,
 346                 .procname       = "sched_rt_period_us",
 347                 .data           = &sysctl_sched_rt_period,
 348                 .maxlen         = sizeof(unsigned int),
 349                 .mode           = 0644,
 350                 .proc_handler   = &sched_rt_handler,
 351         },
 352         {
 353                 .ctl_name       = CTL_UNNUMBERED,
 354                 .procname       = "sched_rt_runtime_us",
 355                 .data           = &sysctl_sched_rt_runtime,
 356                 .maxlen         = sizeof(int),
 357                 .mode           = 0644,
 358                 .proc_handler   = &sched_rt_handler,
 359         },
 360         {
 361                 .ctl_name       = CTL_UNNUMBERED,
 362                 .procname       = "sched_compat_yield",
 363                 .data           = &sysctl_sched_compat_yield,
 364                 .maxlen         = sizeof(unsigned int),
 365                 .mode           = 0644,
 366                 .proc_handler   = &proc_dointvec,
 367         },
 368 #ifdef CONFIG_PROVE_LOCKING
 369         {
 370                 .ctl_name       = CTL_UNNUMBERED,
 371                 .procname       = "prove_locking",
 372                 .data           = &prove_locking,
 373                 .maxlen         = sizeof(int),
 374                 .mode           = 0644,
 375                 .proc_handler   = &proc_dointvec,
 376         },
 377 #endif
 378 #ifdef CONFIG_LOCK_STAT
 379         {
 380                 .ctl_name       = CTL_UNNUMBERED,
 381                 .procname       = "lock_stat",
 382                 .data           = &lock_stat,
 383                 .maxlen         = sizeof(int),
 384                 .mode           = 0644,
 385                 .proc_handler   = &proc_dointvec,
 386         },
 387 #endif
 388         {
 389                 .ctl_name       = KERN_PANIC,
 390                 .procname       = "panic",
 391                 .data           = &panic_timeout,
 392                 .maxlen         = sizeof(int),
 393                 .mode           = 0644,
 394                 .proc_handler   = &proc_dointvec,
 395         },
 396         {
 397                 .ctl_name       = KERN_CORE_USES_PID,
 398                 .procname       = "core_uses_pid",
 399                 .data           = &core_uses_pid,
 400                 .maxlen         = sizeof(int),
 401                 .mode           = 0644,
 402                 .proc_handler   = &proc_dointvec,
 403         },
 404         {
 405                 .ctl_name       = KERN_CORE_PATTERN,
 406                 .procname       = "core_pattern",
 407                 .data           = core_pattern,
 408                 .maxlen         = CORENAME_MAX_SIZE,
 409                 .mode           = 0644,
 410                 .proc_handler   = &proc_dostring,
 411                 .strategy       = &sysctl_string,
 412         },
 413 #ifdef CONFIG_PROC_SYSCTL
 414         {
 415                 .procname       = "tainted",
 416                 .maxlen         = sizeof(long),
 417                 .mode           = 0644,
 418                 .proc_handler   = &proc_taint,
 419         },
 420 #endif
 421 #ifdef CONFIG_LATENCYTOP
 422         {
 423                 .procname       = "latencytop",
 424                 .data           = &latencytop_enabled,
 425                 .maxlen         = sizeof(int),
 426                 .mode           = 0644,
 427                 .proc_handler   = &proc_dointvec,
 428         },
 429 #endif
 430 #ifdef CONFIG_BLK_DEV_INITRD
 431         {
 432                 .ctl_name       = KERN_REALROOTDEV,
 433                 .procname       = "real-root-dev",
 434                 .data           = &real_root_dev,
 435                 .maxlen         = sizeof(int),
 436                 .mode           = 0644,
 437                 .proc_handler   = &proc_dointvec,
 438         },
 439 #endif
 440         {
 441                 .ctl_name       = CTL_UNNUMBERED,
 442                 .procname       = "print-fatal-signals",
 443                 .data           = &print_fatal_signals,
 444                 .maxlen         = sizeof(int),
 445                 .mode           = 0644,
 446                 .proc_handler   = &proc_dointvec,
 447         },
 448 #ifdef CONFIG_SPARC
 449         {
 450                 .ctl_name       = KERN_SPARC_REBOOT,
 451                 .procname       = "reboot-cmd",
 452                 .data           = reboot_command,
 453                 .maxlen         = 256,
 454                 .mode           = 0644,
 455                 .proc_handler   = &proc_dostring,
 456                 .strategy       = &sysctl_string,
 457         },
 458         {
 459                 .ctl_name       = KERN_SPARC_STOP_A,
 460                 .procname       = "stop-a",
 461                 .data           = &stop_a_enabled,
 462                 .maxlen         = sizeof (int),
 463                 .mode           = 0644,
 464                 .proc_handler   = &proc_dointvec,
 465         },
 466         {
 467                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 468                 .procname       = "scons-poweroff",
 469                 .data           = &scons_pwroff,
 470                 .maxlen         = sizeof (int),
 471                 .mode           = 0644,
 472                 .proc_handler   = &proc_dointvec,
 473         },
 474 #endif
 475 #ifdef CONFIG_SPARC64
 476         {
 477                 .ctl_name       = CTL_UNNUMBERED,
 478                 .procname       = "tsb-ratio",
 479                 .data           = &sysctl_tsb_ratio,
 480                 .maxlen         = sizeof (int),
 481                 .mode           = 0644,
 482                 .proc_handler   = &proc_dointvec,
 483         },
 484 #endif
 485 #ifdef __hppa__
 486         {
 487                 .ctl_name       = KERN_HPPA_PWRSW,
 488                 .procname       = "soft-power",
 489                 .data           = &pwrsw_enabled,
 490                 .maxlen         = sizeof (int),
 491                 .mode           = 0644,
 492                 .proc_handler   = &proc_dointvec,
 493         },
 494         {
 495                 .ctl_name       = KERN_HPPA_UNALIGNED,
 496                 .procname       = "unaligned-trap",
 497                 .data           = &unaligned_enabled,
 498                 .maxlen         = sizeof (int),
 499                 .mode           = 0644,
 500                 .proc_handler   = &proc_dointvec,
 501         },
 502 #endif
 503         {
 504                 .ctl_name       = KERN_CTLALTDEL,
 505                 .procname       = "ctrl-alt-del",
 506                 .data           = &C_A_D,
 507                 .maxlen         = sizeof(int),
 508                 .mode           = 0644,
 509                 .proc_handler   = &proc_dointvec,
 510         },
 511 #ifdef CONFIG_FUNCTION_TRACER
 512         {
 513                 .ctl_name       = CTL_UNNUMBERED,
 514                 .procname       = "ftrace_enabled",
 515                 .data           = &ftrace_enabled,
 516                 .maxlen         = sizeof(int),
 517                 .mode           = 0644,
 518                 .proc_handler   = &ftrace_enable_sysctl,
 519         },
 520 #endif
 521 #ifdef CONFIG_STACK_TRACER
 522         {
 523                 .ctl_name       = CTL_UNNUMBERED,
 524                 .procname       = "stack_tracer_enabled",
 525                 .data           = &stack_tracer_enabled,
 526                 .maxlen         = sizeof(int),
 527                 .mode           = 0644,
 528                 .proc_handler   = &stack_trace_sysctl,
 529         },
 530 #endif
 531 #ifdef CONFIG_TRACING
 532         {
 533                 .ctl_name       = CTL_UNNUMBERED,
 534                 .procname       = "ftrace_dump_on_oops",
 535                 .data           = &ftrace_dump_on_oops,
 536                 .maxlen         = sizeof(int),
 537                 .mode           = 0644,
 538                 .proc_handler   = &proc_dointvec,
 539         },
 540 #endif
 541 #ifdef CONFIG_MODULES
 542         {
 543                 .ctl_name       = KERN_MODPROBE,
 544                 .procname       = "modprobe",
 545                 .data           = &modprobe_path,
 546                 .maxlen         = KMOD_PATH_LEN,
 547                 .mode           = 0644,
 548                 .proc_handler   = &proc_dostring,
 549                 .strategy       = &sysctl_string,
 550         },
 551         {
 552                 .ctl_name       = CTL_UNNUMBERED,
 553                 .procname       = "modules_disabled",
 554                 .data           = &modules_disabled,
 555                 .maxlen         = sizeof(int),
 556                 .mode           = 0644,
 557                 /* only handle a transition from default "0" to "1" */
 558                 .proc_handler   = &proc_dointvec_minmax,
 559                 .extra1         = &one,
 560                 .extra2         = &one,
 561         },
 562 #endif
 563 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 564         {
 565                 .ctl_name       = KERN_HOTPLUG,
 566                 .procname       = "hotplug",
 567                 .data           = &uevent_helper,
 568                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 569                 .mode           = 0644,
 570                 .proc_handler   = &proc_dostring,
 571                 .strategy       = &sysctl_string,
 572         },
 573 #endif
 574 #ifdef CONFIG_CHR_DEV_SG
 575         {
 576                 .ctl_name       = KERN_SG_BIG_BUFF,
 577                 .procname       = "sg-big-buff",
 578                 .data           = &sg_big_buff,
 579                 .maxlen         = sizeof (int),
 580                 .mode           = 0444,
 581                 .proc_handler   = &proc_dointvec,
 582         },
 583 #endif
 584 #ifdef CONFIG_BSD_PROCESS_ACCT
 585         {
 586                 .ctl_name       = KERN_ACCT,
 587                 .procname       = "acct",
 588                 .data           = &acct_parm,
 589                 .maxlen         = 3*sizeof(int),
 590                 .mode           = 0644,
 591                 .proc_handler   = &proc_dointvec,
 592         },
 593 #endif
 594 #ifdef CONFIG_MAGIC_SYSRQ
 595         {
 596                 .ctl_name       = KERN_SYSRQ,
 597                 .procname       = "sysrq",
 598                 .data           = &__sysrq_enabled,
 599                 .maxlen         = sizeof (int),
 600                 .mode           = 0644,
 601                 .proc_handler   = &proc_dointvec,
 602         },
 603 #endif
 604 #ifdef CONFIG_PROC_SYSCTL
 605         {
 606                 .procname       = "cad_pid",
 607                 .data           = NULL,
 608                 .maxlen         = sizeof (int),
 609                 .mode           = 0600,
 610                 .proc_handler   = &proc_do_cad_pid,
 611         },
 612 #endif
 613         {
 614                 .ctl_name       = KERN_MAX_THREADS,
 615                 .procname       = "threads-max",
 616                 .data           = &max_threads,
 617                 .maxlen         = sizeof(int),
 618                 .mode           = 0644,
 619                 .proc_handler   = &proc_dointvec,
 620         },
 621         {
 622                 .ctl_name       = KERN_RANDOM,
 623                 .procname       = "random",
 624                 .mode           = 0555,
 625                 .child          = random_table,
 626         },
 627         {
 628                 .ctl_name       = KERN_OVERFLOWUID,
 629                 .procname       = "overflowuid",
 630                 .data           = &overflowuid,
 631                 .maxlen         = sizeof(int),
 632                 .mode           = 0644,
 633                 .proc_handler   = &proc_dointvec_minmax,
 634                 .strategy       = &sysctl_intvec,
 635                 .extra1         = &minolduid,
 636                 .extra2         = &maxolduid,
 637         },
 638         {
 639                 .ctl_name       = KERN_OVERFLOWGID,
 640                 .procname       = "overflowgid",
 641                 .data           = &overflowgid,
 642                 .maxlen         = sizeof(int),
 643                 .mode           = 0644,
 644                 .proc_handler   = &proc_dointvec_minmax,
 645                 .strategy       = &sysctl_intvec,
 646                 .extra1         = &minolduid,
 647                 .extra2         = &maxolduid,
 648         },
 649 #ifdef CONFIG_S390
 650 #ifdef CONFIG_MATHEMU
 651         {
 652                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 653                 .procname       = "ieee_emulation_warnings",
 654                 .data           = &sysctl_ieee_emulation_warnings,
 655                 .maxlen         = sizeof(int),
 656                 .mode           = 0644,
 657                 .proc_handler   = &proc_dointvec,
 658         },
 659 #endif
 660         {
 661                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 662                 .procname       = "userprocess_debug",
 663                 .data           = &sysctl_userprocess_debug,
 664                 .maxlen         = sizeof(int),
 665                 .mode           = 0644,
 666                 .proc_handler   = &proc_dointvec,
 667         },
 668 #endif
 669         {
 670                 .ctl_name       = KERN_PIDMAX,
 671                 .procname       = "pid_max",
 672                 .data           = &pid_max,
 673                 .maxlen         = sizeof (int),
 674                 .mode           = 0644,
 675                 .proc_handler   = &proc_dointvec_minmax,
 676                 .strategy       = sysctl_intvec,
 677                 .extra1         = &pid_max_min,
 678                 .extra2         = &pid_max_max,
 679         },
 680         {
 681                 .ctl_name       = KERN_PANIC_ON_OOPS,
 682                 .procname       = "panic_on_oops",
 683                 .data           = &panic_on_oops,
 684                 .maxlen         = sizeof(int),
 685                 .mode           = 0644,
 686                 .proc_handler   = &proc_dointvec,
 687         },
 688 #if defined CONFIG_PRINTK
 689         {
 690                 .ctl_name       = KERN_PRINTK,
 691                 .procname       = "printk",
 692                 .data           = &console_loglevel,
 693                 .maxlen         = 4*sizeof(int),
 694                 .mode           = 0644,
 695                 .proc_handler   = &proc_dointvec,
 696         },
 697         {
 698                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 699                 .procname       = "printk_ratelimit",
 700                 .data           = &printk_ratelimit_state.interval,
 701                 .maxlen         = sizeof(int),
 702                 .mode           = 0644,
 703                 .proc_handler   = &proc_dointvec_jiffies,
 704                 .strategy       = &sysctl_jiffies,
 705         },
 706         {
 707                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 708                 .procname       = "printk_ratelimit_burst",
 709                 .data           = &printk_ratelimit_state.burst,
 710                 .maxlen         = sizeof(int),
 711                 .mode           = 0644,
 712                 .proc_handler   = &proc_dointvec,
 713         },
 714 #endif
 715         {
 716                 .ctl_name       = KERN_NGROUPS_MAX,
 717                 .procname       = "ngroups_max",
 718                 .data           = &ngroups_max,
 719                 .maxlen         = sizeof (int),
 720                 .mode           = 0444,
 721                 .proc_handler   = &proc_dointvec,
 722         },
 723 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 724         {
 725                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 726                 .procname       = "unknown_nmi_panic",
 727                 .data           = &unknown_nmi_panic,
 728                 .maxlen         = sizeof (int),
 729                 .mode           = 0644,
 730                 .proc_handler   = &proc_dointvec,
 731         },
 732         {
 733                 .procname       = "nmi_watchdog",
 734                 .data           = &nmi_watchdog_enabled,
 735                 .maxlen         = sizeof (int),
 736                 .mode           = 0644,
 737                 .proc_handler   = &proc_nmi_enabled,
 738         },
 739 #endif
 740 #if defined(CONFIG_X86)
 741         {
 742                 .ctl_name       = KERN_PANIC_ON_NMI,
 743                 .procname       = "panic_on_unrecovered_nmi",
 744                 .data           = &panic_on_unrecovered_nmi,
 745                 .maxlen         = sizeof(int),
 746                 .mode           = 0644,
 747                 .proc_handler   = &proc_dointvec,
 748         },
 749         {
 750                 .ctl_name       = CTL_UNNUMBERED,
 751                 .procname       = "panic_on_io_nmi",
 752                 .data           = &panic_on_io_nmi,
 753                 .maxlen         = sizeof(int),
 754                 .mode           = 0644,
 755                 .proc_handler   = &proc_dointvec,
 756         },
 757         {
 758                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 759                 .procname       = "bootloader_type",
 760                 .data           = &bootloader_type,
 761                 .maxlen         = sizeof (int),
 762                 .mode           = 0444,
 763                 .proc_handler   = &proc_dointvec,
 764         },
 765         {
 766                 .ctl_name       = CTL_UNNUMBERED,
 767                 .procname       = "bootloader_version",
 768                 .data           = &bootloader_version,
 769                 .maxlen         = sizeof (int),
 770                 .mode           = 0444,
 771                 .proc_handler   = &proc_dointvec,
 772         },
 773         {
 774                 .ctl_name       = CTL_UNNUMBERED,
 775                 .procname       = "kstack_depth_to_print",
 776                 .data           = &kstack_depth_to_print,
 777                 .maxlen         = sizeof(int),
 778                 .mode           = 0644,
 779                 .proc_handler   = &proc_dointvec,
 780         },
 781         {
 782                 .ctl_name       = CTL_UNNUMBERED,
 783                 .procname       = "io_delay_type",
 784                 .data           = &io_delay_type,
 785                 .maxlen         = sizeof(int),
 786                 .mode           = 0644,
 787                 .proc_handler   = &proc_dointvec,
 788         },
 789 #endif
 790 #if defined(CONFIG_MMU)
 791         {
 792                 .ctl_name       = KERN_RANDOMIZE,
 793                 .procname       = "randomize_va_space",
 794                 .data           = &randomize_va_space,
 795                 .maxlen         = sizeof(int),
 796                 .mode           = 0644,
 797                 .proc_handler   = &proc_dointvec,
 798         },
 799 #endif
 800 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 801         {
 802                 .ctl_name       = KERN_SPIN_RETRY,
 803                 .procname       = "spin_retry",
 804                 .data           = &spin_retry,
 805                 .maxlen         = sizeof (int),
 806                 .mode           = 0644,
 807                 .proc_handler   = &proc_dointvec,
 808         },
 809 #endif
 810 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 811         {
 812                 .procname       = "acpi_video_flags",
 813                 .data           = &acpi_realmode_flags,
 814                 .maxlen         = sizeof (unsigned long),
 815                 .mode           = 0644,
 816                 .proc_handler   = &proc_doulongvec_minmax,
 817         },
 818 #endif
 819 #ifdef CONFIG_IA64
 820         {
 821                 .ctl_name       = KERN_IA64_UNALIGNED,
 822                 .procname       = "ignore-unaligned-usertrap",
 823                 .data           = &no_unaligned_warning,
 824                 .maxlen         = sizeof (int),
 825                 .mode           = 0644,
 826                 .proc_handler   = &proc_dointvec,
 827         },
 828         {
 829                 .ctl_name       = CTL_UNNUMBERED,
 830                 .procname       = "unaligned-dump-stack",
 831                 .data           = &unaligned_dump_stack,
 832                 .maxlen         = sizeof (int),
 833                 .mode           = 0644,
 834                 .proc_handler   = &proc_dointvec,
 835         },
 836 #endif
 837 #ifdef CONFIG_DETECT_SOFTLOCKUP
 838         {
 839                 .ctl_name       = CTL_UNNUMBERED,
 840                 .procname       = "softlockup_panic",
 841                 .data           = &softlockup_panic,
 842                 .maxlen         = sizeof(int),
 843                 .mode           = 0644,
 844                 .proc_handler   = &proc_dointvec_minmax,
 845                 .strategy       = &sysctl_intvec,
 846                 .extra1         = &zero,
 847                 .extra2         = &one,
 848         },
 849         {
 850                 .ctl_name       = CTL_UNNUMBERED,
 851                 .procname       = "softlockup_thresh",
 852                 .data           = &softlockup_thresh,
 853                 .maxlen         = sizeof(int),
 854                 .mode           = 0644,
 855                 .proc_handler   = &proc_dosoftlockup_thresh,
 856                 .strategy       = &sysctl_intvec,
 857                 .extra1         = &neg_one,
 858                 .extra2         = &sixty,
 859         },
 860 #endif
 861 #ifdef CONFIG_DETECT_HUNG_TASK
 862         {
 863                 .ctl_name       = CTL_UNNUMBERED,
 864                 .procname       = "hung_task_panic",
 865                 .data           = &sysctl_hung_task_panic,
 866                 .maxlen         = sizeof(int),
 867                 .mode           = 0644,
 868                 .proc_handler   = &proc_dointvec_minmax,
 869                 .strategy       = &sysctl_intvec,
 870                 .extra1         = &zero,
 871                 .extra2         = &one,
 872         },
 873         {
 874                 .ctl_name       = CTL_UNNUMBERED,
 875                 .procname       = "hung_task_check_count",
 876                 .data           = &sysctl_hung_task_check_count,
 877                 .maxlen         = sizeof(unsigned long),
 878                 .mode           = 0644,
 879                 .proc_handler   = &proc_doulongvec_minmax,
 880                 .strategy       = &sysctl_intvec,
 881         },
 882         {
 883                 .ctl_name       = CTL_UNNUMBERED,
 884                 .procname       = "hung_task_timeout_secs",
 885                 .data           = &sysctl_hung_task_timeout_secs,
 886                 .maxlen         = sizeof(unsigned long),
 887                 .mode           = 0644,
 888                 .proc_handler   = &proc_dohung_task_timeout_secs,
 889                 .strategy       = &sysctl_intvec,
 890         },
 891         {
 892                 .ctl_name       = CTL_UNNUMBERED,
 893                 .procname       = "hung_task_warnings",
 894                 .data           = &sysctl_hung_task_warnings,
 895                 .maxlen         = sizeof(unsigned long),
 896                 .mode           = 0644,
 897                 .proc_handler   = &proc_doulongvec_minmax,
 898                 .strategy       = &sysctl_intvec,
 899         },
 900 #endif
 901 #ifdef CONFIG_COMPAT
 902         {
 903                 .ctl_name       = KERN_COMPAT_LOG,
 904                 .procname       = "compat-log",
 905                 .data           = &compat_log,
 906                 .maxlen         = sizeof (int),
 907                 .mode           = 0644,
 908                 .proc_handler   = &proc_dointvec,
 909         },
 910 #endif
 911 #ifdef CONFIG_RT_MUTEXES
 912         {
 913                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 914                 .procname       = "max_lock_depth",
 915                 .data           = &max_lock_depth,
 916                 .maxlen         = sizeof(int),
 917                 .mode           = 0644,
 918                 .proc_handler   = &proc_dointvec,
 919         },
 920 #endif
 921         {
 922                 .ctl_name       = CTL_UNNUMBERED,
 923                 .procname       = "poweroff_cmd",
 924                 .data           = &poweroff_cmd,
 925                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 926                 .mode           = 0644,
 927                 .proc_handler   = &proc_dostring,
 928                 .strategy       = &sysctl_string,
 929         },
 930 #ifdef CONFIG_KEYS
 931         {
 932                 .ctl_name       = CTL_UNNUMBERED,
 933                 .procname       = "keys",
 934                 .mode           = 0555,
 935                 .child          = key_sysctls,
 936         },
 937 #endif
 938 #ifdef CONFIG_RCU_TORTURE_TEST
 939         {
 940                 .ctl_name       = CTL_UNNUMBERED,
 941                 .procname       = "rcutorture_runnable",
 942                 .data           = &rcutorture_runnable,
 943                 .maxlen         = sizeof(int),
 944                 .mode           = 0644,
 945                 .proc_handler   = &proc_dointvec,
 946         },
 947 #endif
 948 #ifdef CONFIG_SLOW_WORK
 949         {
 950                 .ctl_name       = CTL_UNNUMBERED,
 951                 .procname       = "slow-work",
 952                 .mode           = 0555,
 953                 .child          = slow_work_sysctls,
 954         },
 955 #endif
 956 #ifdef CONFIG_PERF_COUNTERS
 957         {
 958                 .ctl_name       = CTL_UNNUMBERED,
 959                 .procname       = "perf_counter_paranoid",
 960                 .data           = &sysctl_perf_counter_paranoid,
 961                 .maxlen         = sizeof(sysctl_perf_counter_paranoid),
 962                 .mode           = 0644,
 963                 .proc_handler   = &proc_dointvec,
 964         },
 965         {
 966                 .ctl_name       = CTL_UNNUMBERED,
 967                 .procname       = "perf_counter_mlock_kb",
 968                 .data           = &sysctl_perf_counter_mlock,
 969                 .maxlen         = sizeof(sysctl_perf_counter_mlock),
 970                 .mode           = 0644,
 971                 .proc_handler   = &proc_dointvec,
 972         },
 973         {
 974                 .ctl_name       = CTL_UNNUMBERED,
 975                 .procname       = "perf_counter_max_sample_rate",
 976                 .data           = &sysctl_perf_counter_sample_rate,
 977                 .maxlen         = sizeof(sysctl_perf_counter_sample_rate),
 978                 .mode           = 0644,
 979                 .proc_handler   = &proc_dointvec,
 980         },
 981 #endif
 982 #ifdef CONFIG_KMEMCHECK
 983         {
 984                 .ctl_name       = CTL_UNNUMBERED,
 985                 .procname       = "kmemcheck",
 986                 .data           = &kmemcheck_enabled,
 987                 .maxlen         = sizeof(int),
 988                 .mode           = 0644,
 989                 .proc_handler   = &proc_dointvec,
 990         },
 991 #endif
 992
 993 /*
 994  * NOTE: do not add new entries to this table unless you have read
 995  * Documentation/sysctl/ctl_unnumbered.txt
 996  */
 997         { .ctl_name = 0 }
 998 };
 999
1000 static struct ctl_table vm_table[] = {
1001         {
1002                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
1003                 .procname       = "overcommit_memory",
1004                 .data           = &sysctl_overcommit_memory,
1005                 .maxlen         = sizeof(sysctl_overcommit_memory),
1006                 .mode           = 0644,
1007                 .proc_handler   = &proc_dointvec,
1008         },
1009         {
1010                 .ctl_name       = VM_PANIC_ON_OOM,
1011                 .procname       = "panic_on_oom",
1012                 .data           = &sysctl_panic_on_oom,
1013                 .maxlen         = sizeof(sysctl_panic_on_oom),
1014                 .mode           = 0644,
1015                 .proc_handler   = &proc_dointvec,
1016         },
1017         {
1018                 .ctl_name       = CTL_UNNUMBERED,
1019                 .procname       = "oom_kill_allocating_task",
1020                 .data           = &sysctl_oom_kill_allocating_task,
1021                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
1022                 .mode           = 0644,
1023                 .proc_handler   = &proc_dointvec,
1024         },
1025         {
1026                 .ctl_name       = CTL_UNNUMBERED,
1027                 .procname       = "oom_dump_tasks",
1028                 .data           = &sysctl_oom_dump_tasks,
1029                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
1030                 .mode           = 0644,
1031                 .proc_handler   = &proc_dointvec,
1032         },
1033         {
1034                 .ctl_name       = VM_OVERCOMMIT_RATIO,
1035                 .procname       = "overcommit_ratio",
1036                 .data           = &sysctl_overcommit_ratio,
1037                 .maxlen         = sizeof(sysctl_overcommit_ratio),
1038                 .mode           = 0644,
1039                 .proc_handler   = &proc_dointvec,
1040         },
1041         {
1042                 .ctl_name       = VM_PAGE_CLUSTER,
1043                 .procname       = "page-cluster",
1044                 .data           = &page_cluster,
1045                 .maxlen         = sizeof(int),
1046                 .mode           = 0644,
1047                 .proc_handler   = &proc_dointvec,
1048         },
1049         {
1050                 .ctl_name       = VM_DIRTY_BACKGROUND,
1051                 .procname       = "dirty_background_ratio",
1052                 .data           = &dirty_background_ratio,
1053                 .maxlen         = sizeof(dirty_background_ratio),
1054                 .mode           = 0644,
1055                 .proc_handler   = &dirty_background_ratio_handler,
1056                 .strategy       = &sysctl_intvec,
1057                 .extra1         = &zero,
1058                 .extra2         = &one_hundred,
1059         },
1060         {
1061                 .ctl_name       = CTL_UNNUMBERED,
1062                 .procname       = "dirty_background_bytes",
1063                 .data           = &dirty_background_bytes,
1064                 .maxlen         = sizeof(dirty_background_bytes),
1065                 .mode           = 0644,
1066                 .proc_handler   = &dirty_background_bytes_handler,
1067                 .strategy       = &sysctl_intvec,
1068                 .extra1         = &one_ul,
1069         },
1070         {
1071                 .ctl_name       = VM_DIRTY_RATIO,
1072                 .procname       = "dirty_ratio",
1073                 .data           = &vm_dirty_ratio,
1074                 .maxlen         = sizeof(vm_dirty_ratio),
1075                 .mode           = 0644,
1076                 .proc_handler   = &dirty_ratio_handler,
1077                 .strategy       = &sysctl_intvec,
1078                 .extra1         = &zero,
1079                 .extra2         = &one_hundred,
1080         },
1081         {
1082                 .ctl_name       = CTL_UNNUMBERED,
1083                 .procname       = "dirty_bytes",
1084                 .data           = &vm_dirty_bytes,
1085                 .maxlen         = sizeof(vm_dirty_bytes),
1086                 .mode           = 0644,
1087                 .proc_handler   = &dirty_bytes_handler,
1088                 .strategy       = &sysctl_intvec,
1089                 .extra1         = &dirty_bytes_min,
1090         },
1091         {
1092                 .procname       = "dirty_writeback_centisecs",
1093                 .data           = &dirty_writeback_interval,
1094                 .maxlen         = sizeof(dirty_writeback_interval),
1095                 .mode           = 0644,
1096                 .proc_handler   = &dirty_writeback_centisecs_handler,
1097         },
1098         {
1099                 .procname       = "dirty_expire_centisecs",
1100                 .data           = &dirty_expire_interval,
1101                 .maxlen         = sizeof(dirty_expire_interval),
1102                 .mode           = 0644,
1103                 .proc_handler   = &proc_dointvec,
1104         },
1105         {
1106                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
1107                 .procname       = "nr_pdflush_threads",
1108                 .data           = &nr_pdflush_threads,
1109                 .maxlen         = sizeof nr_pdflush_threads,
1110                 .mode           = 0444 /* read-only*/,
1111                 .proc_handler   = &proc_dointvec,
1112         },
1113         {
1114                 .ctl_name       = VM_SWAPPINESS,
1115                 .procname       = "swappiness",
1116                 .data           = &vm_swappiness,
1117                 .maxlen         = sizeof(vm_swappiness),
1118                 .mode           = 0644,
1119                 .proc_handler   = &proc_dointvec_minmax,
1120                 .strategy       = &sysctl_intvec,
1121                 .extra1         = &zero,
1122                 .extra2         = &one_hundred,
1123         },
1124 #ifdef CONFIG_HUGETLB_PAGE
1125          {
1126                 .procname       = "nr_hugepages",
1127                 .data           = NULL,
1128                 .maxlen         = sizeof(unsigned long),
1129                 .mode           = 0644,
1130                 .proc_handler   = &hugetlb_sysctl_handler,
1131                 .extra1         = (void *)&hugetlb_zero,
1132                 .extra2         = (void *)&hugetlb_infinity,
1133          },
1134          {
1135                 .ctl_name       = VM_HUGETLB_GROUP,
1136                 .procname       = "hugetlb_shm_group",
1137                 .data           = &sysctl_hugetlb_shm_group,
1138                 .maxlen         = sizeof(gid_t),
1139                 .mode           = 0644,
1140                 .proc_handler   = &proc_dointvec,
1141          },
1142          {
1143                 .ctl_name       = CTL_UNNUMBERED,
1144                 .procname       = "hugepages_treat_as_movable",
1145                 .data           = &hugepages_treat_as_movable,
1146                 .maxlen         = sizeof(int),
1147                 .mode           = 0644,
1148                 .proc_handler   = &hugetlb_treat_movable_handler,
1149         },
1150         {
1151                 .ctl_name       = CTL_UNNUMBERED,
1152                 .procname       = "nr_overcommit_hugepages",
1153                 .data           = NULL,
1154                 .maxlen         = sizeof(unsigned long),
1155                 .mode           = 0644,
1156                 .proc_handler   = &hugetlb_overcommit_handler,
1157                 .extra1         = (void *)&hugetlb_zero,
1158                 .extra2         = (void *)&hugetlb_infinity,
1159         },
1160 #endif
1161         {
1162                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
1163                 .procname       = "lowmem_reserve_ratio",
1164                 .data           = &sysctl_lowmem_reserve_ratio,
1165                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1166                 .mode           = 0644,
1167                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
1168                 .strategy       = &sysctl_intvec,
1169         },
1170         {
1171                 .ctl_name       = VM_DROP_PAGECACHE,
1172                 .procname       = "drop_caches",
1173                 .data           = &sysctl_drop_caches,
1174                 .maxlen         = sizeof(int),
1175                 .mode           = 0644,
1176                 .proc_handler   = drop_caches_sysctl_handler,
1177                 .strategy       = &sysctl_intvec,
1178         },
1179         {
1180                 .ctl_name       = VM_MIN_FREE_KBYTES,
1181                 .procname       = "min_free_kbytes",
1182                 .data           = &min_free_kbytes,
1183                 .maxlen         = sizeof(min_free_kbytes),
1184                 .mode           = 0644,
1185                 .proc_handler   = &min_free_kbytes_sysctl_handler,
1186                 .strategy       = &sysctl_intvec,
1187                 .extra1         = &zero,
1188         },
1189         {
1190                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
1191                 .procname       = "percpu_pagelist_fraction",
1192                 .data           = &percpu_pagelist_fraction,
1193                 .maxlen         = sizeof(percpu_pagelist_fraction),
1194                 .mode           = 0644,
1195                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
1196                 .strategy       = &sysctl_intvec,
1197                 .extra1         = &min_percpu_pagelist_fract,
1198         },
1199 #ifdef CONFIG_MMU
1200         {
1201                 .ctl_name       = VM_MAX_MAP_COUNT,
1202                 .procname       = "max_map_count",
1203                 .data           = &sysctl_max_map_count,
1204                 .maxlen         = sizeof(sysctl_max_map_count),
1205                 .mode           = 0644,
1206                 .proc_handler   = &proc_dointvec
1207         },
1208 #else
1209         {
1210                 .ctl_name       = CTL_UNNUMBERED,
1211                 .procname       = "nr_trim_pages",
1212                 .data           = &sysctl_nr_trim_pages,
1213                 .maxlen         = sizeof(sysctl_nr_trim_pages),
1214                 .mode           = 0644,
1215                 .proc_handler   = &proc_dointvec_minmax,
1216                 .strategy       = &sysctl_intvec,
1217                 .extra1         = &zero,
1218         },
1219 #endif
1220         {
1221                 .ctl_name       = VM_LAPTOP_MODE,
1222                 .procname       = "laptop_mode",
1223                 .data           = &laptop_mode,
1224                 .maxlen         = sizeof(laptop_mode),
1225                 .mode           = 0644,
1226                 .proc_handler   = &proc_dointvec_jiffies,
1227                 .strategy       = &sysctl_jiffies,
1228         },
1229         {
1230                 .ctl_name       = VM_BLOCK_DUMP,
1231                 .procname       = "block_dump",
1232                 .data           = &block_dump,
1233                 .maxlen         = sizeof(block_dump),
1234                 .mode           = 0644,
1235                 .proc_handler   = &proc_dointvec,
1236                 .strategy       = &sysctl_intvec,
1237                 .extra1         = &zero,
1238         },
1239         {
1240                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
1241                 .procname       = "vfs_cache_pressure",
1242                 .data           = &sysctl_vfs_cache_pressure,
1243                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1244                 .mode           = 0644,
1245                 .proc_handler   = &proc_dointvec,
1246                 .strategy       = &sysctl_intvec,
1247                 .extra1         = &zero,
1248         },
1249 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1250         {
1251                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
1252                 .procname       = "legacy_va_layout",
1253                 .data           = &sysctl_legacy_va_layout,
1254                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1255                 .mode           = 0644,
1256                 .proc_handler   = &proc_dointvec,
1257                 .strategy       = &sysctl_intvec,
1258                 .extra1         = &zero,
1259         },
1260 #endif
1261 #ifdef CONFIG_NUMA
1262         {
1263                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
1264                 .procname       = "zone_reclaim_mode",
1265                 .data           = &zone_reclaim_mode,
1266                 .maxlen         = sizeof(zone_reclaim_mode),
1267                 .mode           = 0644,
1268                 .proc_handler   = &proc_dointvec,
1269                 .strategy       = &sysctl_intvec,
1270                 .extra1         = &zero,
1271         },
1272         {
1273                 .ctl_name       = VM_MIN_UNMAPPED,
1274                 .procname       = "min_unmapped_ratio",
1275                 .data           = &sysctl_min_unmapped_ratio,
1276                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1277                 .mode           = 0644,
1278                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1279                 .strategy       = &sysctl_intvec,
1280                 .extra1         = &zero,
1281                 .extra2         = &one_hundred,
1282         },
1283         {
1284                 .ctl_name       = VM_MIN_SLAB,
1285                 .procname       = "min_slab_ratio",
1286                 .data           = &sysctl_min_slab_ratio,
1287                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1288                 .mode           = 0644,
1289                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1290                 .strategy       = &sysctl_intvec,
1291                 .extra1         = &zero,
1292                 .extra2         = &one_hundred,
1293         },
1294 #endif
1295 #ifdef CONFIG_SMP
1296         {
1297                 .ctl_name       = CTL_UNNUMBERED,
1298                 .procname       = "stat_interval",
1299                 .data           = &sysctl_stat_interval,
1300                 .maxlen         = sizeof(sysctl_stat_interval),
1301                 .mode           = 0644,
1302                 .proc_handler   = &proc_dointvec_jiffies,
1303                 .strategy       = &sysctl_jiffies,
1304         },
1305 #endif
1306         {
1307                 .ctl_name       = CTL_UNNUMBERED,
1308                 .procname       = "mmap_min_addr",
1309                 .data           = &mmap_min_addr,
1310                 .maxlen         = sizeof(unsigned long),
1311                 .mode           = 0644,
1312                 .proc_handler   = &proc_doulongvec_minmax,
1313         },
1314 #ifdef CONFIG_NUMA
1315         {
1316                 .ctl_name       = CTL_UNNUMBERED,
1317                 .procname       = "numa_zonelist_order",
1318                 .data           = &numa_zonelist_order,
1319                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1320                 .mode           = 0644,
1321                 .proc_handler   = &numa_zonelist_order_handler,
1322                 .strategy       = &sysctl_string,
1323         },
1324 #endif
1325 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1326    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1327         {
1328                 .ctl_name       = VM_VDSO_ENABLED,
1329                 .procname       = "vdso_enabled",
1330                 .data           = &vdso_enabled,
1331                 .maxlen         = sizeof(vdso_enabled),
1332                 .mode           = 0644,
1333                 .proc_handler   = &proc_dointvec,
1334                 .strategy       = &sysctl_intvec,
1335                 .extra1         = &zero,
1336         },
1337 #endif
1338 #ifdef CONFIG_HIGHMEM
1339         {
1340                 .ctl_name       = CTL_UNNUMBERED,
1341                 .procname       = "highmem_is_dirtyable",
1342                 .data           = &vm_highmem_is_dirtyable,
1343                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1344                 .mode           = 0644,
1345                 .proc_handler   = &proc_dointvec_minmax,
1346                 .strategy       = &sysctl_intvec,
1347                 .extra1         = &zero,
1348                 .extra2         = &one,
1349         },
1350 #endif
1351         {
1352                 .ctl_name       = CTL_UNNUMBERED,
1353                 .procname       = "scan_unevictable_pages",
1354                 .data           = &scan_unevictable_pages,
1355                 .maxlen         = sizeof(scan_unevictable_pages),
1356                 .mode           = 0644,
1357                 .proc_handler   = &scan_unevictable_handler,
1358         },
1359 /*
1360  * NOTE: do not add new entries to this table unless you have read
1361  * Documentation/sysctl/ctl_unnumbered.txt
1362  */
1363         { .ctl_name = 0 }
1364 };
1365
1366 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1367 static struct ctl_table binfmt_misc_table[] = {
1368         { .ctl_name = 0 }
1369 };
1370 #endif
1371
1372 static struct ctl_table fs_table[] = {
1373         {
1374                 .ctl_name       = FS_NRINODE,
1375                 .procname       = "inode-nr",
1376                 .data           = &inodes_stat,
1377                 .maxlen         = 2*sizeof(int),
1378                 .mode           = 0444,
1379                 .proc_handler   = &proc_dointvec,
1380         },
1381         {
1382                 .ctl_name       = FS_STATINODE,
1383                 .procname       = "inode-state",
1384                 .data           = &inodes_stat,
1385                 .maxlen         = 7*sizeof(int),
1386                 .mode           = 0444,
1387                 .proc_handler   = &proc_dointvec,
1388         },
1389         {
1390                 .procname       = "file-nr",
1391                 .data           = &files_stat,
1392                 .maxlen         = 3*sizeof(int),
1393                 .mode           = 0444,
1394                 .proc_handler   = &proc_nr_files,
1395         },
1396         {
1397                 .ctl_name       = FS_MAXFILE,
1398                 .procname       = "file-max",
1399                 .data           = &files_stat.max_files,
1400                 .maxlen         = sizeof(int),
1401                 .mode           = 0644,
1402                 .proc_handler   = &proc_dointvec,
1403         },
1404         {
1405                 .ctl_name       = CTL_UNNUMBERED,
1406                 .procname       = "nr_open",
1407                 .data           = &sysctl_nr_open,
1408                 .maxlen         = sizeof(int),
1409                 .mode           = 0644,
1410                 .proc_handler   = &proc_dointvec_minmax,
1411                 .extra1         = &sysctl_nr_open_min,
1412                 .extra2         = &sysctl_nr_open_max,
1413         },
1414         {
1415                 .ctl_name       = FS_DENTRY,
1416                 .procname       = "dentry-state",
1417                 .data           = &dentry_stat,
1418                 .maxlen         = 6*sizeof(int),
1419                 .mode           = 0444,
1420                 .proc_handler   = &proc_dointvec,
1421         },
1422         {
1423                 .ctl_name       = FS_OVERFLOWUID,
1424                 .procname       = "overflowuid",
1425                 .data           = &fs_overflowuid,
1426                 .maxlen         = sizeof(int),
1427                 .mode           = 0644,
1428                 .proc_handler   = &proc_dointvec_minmax,
1429                 .strategy       = &sysctl_intvec,
1430                 .extra1         = &minolduid,
1431                 .extra2         = &maxolduid,
1432         },
1433         {
1434                 .ctl_name       = FS_OVERFLOWGID,
1435                 .procname       = "overflowgid",
1436                 .data           = &fs_overflowgid,
1437                 .maxlen         = sizeof(int),
1438                 .mode           = 0644,
1439                 .proc_handler   = &proc_dointvec_minmax,
1440                 .strategy       = &sysctl_intvec,
1441                 .extra1         = &minolduid,
1442                 .extra2         = &maxolduid,
1443         },
1444 #ifdef CONFIG_FILE_LOCKING
1445         {
1446                 .ctl_name       = FS_LEASES,
1447                 .procname       = "leases-enable",
1448                 .data           = &leases_enable,
1449                 .maxlen         = sizeof(int),
1450                 .mode           = 0644,
1451                 .proc_handler   = &proc_dointvec,
1452         },
1453 #endif
1454 #ifdef CONFIG_DNOTIFY
1455         {
1456                 .ctl_name       = FS_DIR_NOTIFY,
1457                 .procname       = "dir-notify-enable",
1458                 .data           = &dir_notify_enable,
1459                 .maxlen         = sizeof(int),
1460                 .mode           = 0644,
1461                 .proc_handler   = &proc_dointvec,
1462         },
1463 #endif
1464 #ifdef CONFIG_MMU
1465 #ifdef CONFIG_FILE_LOCKING
1466         {
1467                 .ctl_name       = FS_LEASE_TIME,
1468                 .procname       = "lease-break-time",
1469                 .data           = &lease_break_time,
1470                 .maxlen         = sizeof(int),
1471                 .mode           = 0644,
1472                 .proc_handler   = &proc_dointvec,
1473         },
1474 #endif
1475 #ifdef CONFIG_AIO
1476         {
1477                 .procname       = "aio-nr",
1478                 .data           = &aio_nr,
1479                 .maxlen         = sizeof(aio_nr),
1480                 .mode           = 0444,
1481                 .proc_handler   = &proc_doulongvec_minmax,
1482         },
1483         {
1484                 .procname       = "aio-max-nr",
1485                 .data           = &aio_max_nr,
1486                 .maxlen         = sizeof(aio_max_nr),
1487                 .mode           = 0644,
1488                 .proc_handler   = &proc_doulongvec_minmax,
1489         },
1490 #endif /* CONFIG_AIO */
1491 #ifdef CONFIG_INOTIFY_USER
1492         {
1493                 .ctl_name       = FS_INOTIFY,
1494                 .procname       = "inotify",
1495                 .mode           = 0555,
1496                 .child          = inotify_table,
1497         },
1498 #endif
1499 #ifdef CONFIG_EPOLL
1500         {
1501                 .procname       = "epoll",
1502                 .mode           = 0555,
1503                 .child          = epoll_table,
1504         },
1505 #endif
1506 #endif
1507         {
1508                 .ctl_name       = KERN_SETUID_DUMPABLE,
1509                 .procname       = "suid_dumpable",
1510                 .data           = &suid_dumpable,
1511                 .maxlen         = sizeof(int),
1512                 .mode           = 0644,
1513                 .proc_handler   = &proc_dointvec_minmax,
1514                 .strategy       = &sysctl_intvec,
1515                 .extra1         = &zero,
1516                 .extra2         = &two,
1517         },
1518 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1519         {
1520                 .ctl_name       = CTL_UNNUMBERED,
1521                 .procname       = "binfmt_misc",
1522                 .mode           = 0555,
1523                 .child          = binfmt_misc_table,
1524         },
1525 #endif
1526 /*
1527  * NOTE: do not add new entries to this table unless you have read
1528  * Documentation/sysctl/ctl_unnumbered.txt
1529  */
1530         { .ctl_name = 0 }
1531 };
1532
1533 static struct ctl_table debug_table[] = {
1534 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1535         {
1536                 .ctl_name       = CTL_UNNUMBERED,
1537                 .procname       = "exception-trace",
1538                 .data           = &show_unhandled_signals,
1539                 .maxlen         = sizeof(int),
1540                 .mode           = 0644,
1541                 .proc_handler   = proc_dointvec
1542         },
1543 #endif
1544         { .ctl_name = 0 }
1545 };
1546
1547 static struct ctl_table dev_table[] = {
1548         { .ctl_name = 0 }
1549 };
1550
1551 static DEFINE_SPINLOCK(sysctl_lock);
1552
1553 /* called under sysctl_lock */
1554 static int use_table(struct ctl_table_header *p)
1555 {
1556         if (unlikely(p->unregistering))
1557                 return 0;
1558         p->used++;
1559         return 1;
1560 }
1561
1562 /* called under sysctl_lock */
1563 static void unuse_table(struct ctl_table_header *p)
1564 {
1565         if (!--p->used)
1566                 if (unlikely(p->unregistering))
1567                         complete(p->unregistering);
1568 }
1569
1570 /* called under sysctl_lock, will reacquire if has to wait */
1571 static void start_unregistering(struct ctl_table_header *p)
1572 {
1573         /*
1574          * if p->used is 0, nobody will ever touch that entry again;
1575          * we'll eliminate all paths to it before dropping sysctl_lock
1576          */
1577         if (unlikely(p->used)) {
1578                 struct completion wait;
1579                 init_completion(&wait);
1580                 p->unregistering = &wait;
1581                 spin_unlock(&sysctl_lock);
1582                 wait_for_completion(&wait);
1583                 spin_lock(&sysctl_lock);
1584         } else {
1585                 /* anything non-NULL; we'll never dereference it */
1586                 p->unregistering = ERR_PTR(-EINVAL);
1587         }
1588         /*
1589          * do not remove from the list until nobody holds it; walking the
1590          * list in do_sysctl() relies on that.
1591          */
1592         list_del_init(&p->ctl_entry);
1593 }
1594
1595 void sysctl_head_get(struct ctl_table_header *head)
1596 {
1597         spin_lock(&sysctl_lock);
1598         head->count++;
1599         spin_unlock(&sysctl_lock);
1600 }
1601
1602 void sysctl_head_put(struct ctl_table_header *head)
1603 {
1604         spin_lock(&sysctl_lock);
1605         if (!--head->count)
1606                 kfree(head);
1607         spin_unlock(&sysctl_lock);
1608 }
1609
1610 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1611 {
1612         if (!head)
1613                 BUG();
1614         spin_lock(&sysctl_lock);
1615         if (!use_table(head))
1616                 head = ERR_PTR(-ENOENT);
1617         spin_unlock(&sysctl_lock);
1618         return head;
1619 }
1620
1621 void sysctl_head_finish(struct ctl_table_header *head)
1622 {
1623         if (!head)
1624                 return;
1625         spin_lock(&sysctl_lock);
1626         unuse_table(head);
1627         spin_unlock(&sysctl_lock);
1628 }
1629
1630 static struct ctl_table_set *
1631 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1632 {
1633         struct ctl_table_set *set = &root->default_set;
1634         if (root->lookup)
1635                 set = root->lookup(root, namespaces);
1636         return set;
1637 }
1638
1639 static struct list_head *
1640 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1641 {
1642         struct ctl_table_set *set = lookup_header_set(root, namespaces);
1643         return &set->list;
1644 }
1645
1646 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1647                                             struct ctl_table_header *prev)
1648 {
1649         struct ctl_table_root *root;
1650         struct list_head *header_list;
1651         struct ctl_table_header *head;
1652         struct list_head *tmp;
1653
1654         spin_lock(&sysctl_lock);
1655         if (prev) {
1656                 head = prev;
1657                 tmp = &prev->ctl_entry;
1658                 unuse_table(prev);
1659                 goto next;
1660         }
1661         tmp = &root_table_header.ctl_entry;
1662         for (;;) {
1663                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1664
1665                 if (!use_table(head))
1666                         goto next;
1667                 spin_unlock(&sysctl_lock);
1668                 return head;
1669         next:
1670                 root = head->root;
1671                 tmp = tmp->next;
1672                 header_list = lookup_header_list(root, namespaces);
1673                 if (tmp != header_list)
1674                         continue;
1675
1676                 do {
1677                         root = list_entry(root->root_list.next,
1678                                         struct ctl_table_root, root_list);
1679                         if (root == &sysctl_table_root)
1680                                 goto out;
1681                         header_list = lookup_header_list(root, namespaces);
1682                 } while (list_empty(header_list));
1683                 tmp = header_list->next;
1684         }
1685 out:
1686         spin_unlock(&sysctl_lock);
1687         return NULL;
1688 }
1689
1690 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1691 {
1692         return __sysctl_head_next(current->nsproxy, prev);
1693 }
1694
1695 void register_sysctl_root(struct ctl_table_root *root)
1696 {
1697         spin_lock(&sysctl_lock);
1698         list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1699         spin_unlock(&sysctl_lock);
1700 }
1701
1702 #ifdef CONFIG_SYSCTL_SYSCALL
1703 /* Perform the actual read/write of a sysctl table entry. */
1704 static int do_sysctl_strategy(struct ctl_table_root *root,
1705                         struct ctl_table *table,
1706                         void __user *oldval, size_t __user *oldlenp,
1707                         void __user *newval, size_t newlen)
1708 {
1709         int op = 0, rc;
1710
1711         if (oldval)
1712                 op |= MAY_READ;
1713         if (newval)
1714                 op |= MAY_WRITE;
1715         if (sysctl_perm(root, table, op))
1716                 return -EPERM;
1717
1718         if (table->strategy) {
1719                 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1720                 if (rc < 0)
1721                         return rc;
1722                 if (rc > 0)
1723                         return 0;
1724         }
1725
1726         /* If there is no strategy routine, or if the strategy returns
1727          * zero, proceed with automatic r/w */
1728         if (table->data && table->maxlen) {
1729                 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1730                 if (rc < 0)
1731                         return rc;
1732         }
1733         return 0;
1734 }
1735
1736 static int parse_table(int __user *name, int nlen,
1737                        void __user *oldval, size_t __user *oldlenp,
1738                        void __user *newval, size_t newlen,
1739                        struct ctl_table_root *root,
1740                        struct ctl_table *table)
1741 {
1742         int n;
1743 repeat:
1744         if (!nlen)
1745                 return -ENOTDIR;
1746         if (get_user(n, name))
1747                 return -EFAULT;
1748         for ( ; table->ctl_name || table->procname; table++) {
1749                 if (!table->ctl_name)
1750                         continue;
1751                 if (n == table->ctl_name) {
1752                         int error;
1753                         if (table->child) {
1754                                 if (sysctl_perm(root, table, MAY_EXEC))
1755                                         return -EPERM;
1756                                 name++;
1757                                 nlen--;
1758                                 table = table->child;
1759                                 goto repeat;
1760                         }
1761                         error = do_sysctl_strategy(root, table,
1762                                                    oldval, oldlenp,
1763                                                    newval, newlen);
1764                         return error;
1765                 }
1766         }
1767         return -ENOTDIR;
1768 }
1769
1770 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1771                void __user *newval, size_t newlen)
1772 {
1773         struct ctl_table_header *head;
1774         int error = -ENOTDIR;
1775
1776         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1777                 return -ENOTDIR;
1778         if (oldval) {
1779                 int old_len;
1780                 if (!oldlenp || get_user(old_len, oldlenp))
1781                         return -EFAULT;
1782         }
1783
1784         for (head = sysctl_head_next(NULL); head;
1785                         head = sysctl_head_next(head)) {
1786                 error = parse_table(name, nlen, oldval, oldlenp,
1787                                         newval, newlen,
1788                                         head->root, head->ctl_table);
1789                 if (error != -ENOTDIR) {
1790                         sysctl_head_finish(head);
1791                         break;
1792                 }
1793         }
1794         return error;
1795 }
1796
1797 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1798 {
1799         struct __sysctl_args tmp;
1800         int error;
1801
1802         if (copy_from_user(&tmp, args, sizeof(tmp)))
1803                 return -EFAULT;
1804
1805         error = deprecated_sysctl_warning(&tmp);
1806         if (error)
1807                 goto out;
1808
1809         lock_kernel();
1810         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1811                           tmp.newval, tmp.newlen);
1812         unlock_kernel();
1813 out:
1814         return error;
1815 }
1816 #endif /* CONFIG_SYSCTL_SYSCALL */
1817
1818 /*
1819  * sysctl_perm does NOT grant the superuser all rights automatically, because
1820  * some sysctl variables are readonly even to root.
1821  */
1822
1823 static int test_perm(int mode, int op)
1824 {
1825         if (!current_euid())
1826                 mode >>= 6;
1827         else if (in_egroup_p(0))
1828                 mode >>= 3;
1829         if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1830                 return 0;
1831         return -EACCES;
1832 }
1833
1834 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1835 {
1836         int error;
1837         int mode;
1838
1839         error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1840         if (error)
1841                 return error;
1842
1843         if (root->permissions)
1844                 mode = root->permissions(root, current->nsproxy, table);
1845         else
1846                 mode = table->mode;
1847
1848         return test_perm(mode, op);
1849 }
1850
1851 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1852 {
1853         for (; table->ctl_name || table->procname; table++) {
1854                 table->parent = parent;
1855                 if (table->child)
1856                         sysctl_set_parent(table, table->child);
1857         }
1858 }
1859
1860 static __init int sysctl_init(void)
1861 {
1862         sysctl_set_parent(NULL, root_table);
1863 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1864         {
1865                 int err;
1866                 err = sysctl_check_table(current->nsproxy, root_table);
1867         }
1868 #endif
1869         return 0;
1870 }
1871
1872 core_initcall(sysctl_init);
1873
1874 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1875                                       struct ctl_table *table)
1876 {
1877         struct ctl_table *p;
1878         const char *s = branch->procname;
1879
1880         /* branch should have named subdirectory as its first element */
1881         if (!s || !branch->child)
1882                 return NULL;
1883
1884         /* ... and nothing else */
1885         if (branch[1].procname || branch[1].ctl_name)
1886                 return NULL;
1887
1888         /* table should contain subdirectory with the same name */
1889         for (p = table; p->procname || p->ctl_name; p++) {
1890                 if (!p->child)
1891                         continue;
1892                 if (p->procname && strcmp(p->procname, s) == 0)
1893                         return p;
1894         }
1895         return NULL;
1896 }
1897
1898 /* see if attaching q to p would be an improvement */
1899 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1900 {
1901         struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1902         struct ctl_table *next;
1903         int is_better = 0;
1904         int not_in_parent = !p->attached_by;
1905
1906         while ((next = is_branch_in(by, to)) != NULL) {
1907                 if (by == q->attached_by)
1908                         is_better = 1;
1909                 if (to == p->attached_by)
1910                         not_in_parent = 1;
1911                 by = by->child;
1912                 to = next->child;
1913         }
1914
1915         if (is_better && not_in_parent) {
1916                 q->attached_by = by;
1917                 q->attached_to = to;
1918                 q->parent = p;
1919         }
1920 }
1921
1922 /**
1923  * __register_sysctl_paths - register a sysctl hierarchy
1924  * @root: List of sysctl headers to register on
1925  * @namespaces: Data to compute which lists of sysctl entries are visible
1926  * @path: The path to the directory the sysctl table is in.
1927  * @table: the top-level table structure
1928  *
1929  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1930  * array. A completely 0 filled entry terminates the table.
1931  *
1932  * The members of the &struct ctl_table structure are used as follows:
1933  *
1934  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1935  *            must be unique within that level of sysctl
1936  *
1937  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1938  *            enter a sysctl file
1939  *
1940  * data - a pointer to data for use by proc_handler
1941  *
1942  * maxlen - the maximum size in bytes of the data
1943  *
1944  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1945  *
1946  * child - a pointer to the child sysctl table if this entry is a directory, or
1947  *         %NULL.
1948  *
1949  * proc_handler - the text handler routine (described below)
1950  *
1951  * strategy - the strategy routine (described below)
1952  *
1953  * de - for internal use by the sysctl routines
1954  *
1955  * extra1, extra2 - extra pointers usable by the proc handler routines
1956  *
1957  * Leaf nodes in the sysctl tree will be represented by a single file
1958  * under /proc; non-leaf nodes will be represented by directories.
1959  *
1960  * sysctl(2) can automatically manage read and write requests through
1961  * the sysctl table.  The data and maxlen fields of the ctl_table
1962  * struct enable minimal validation of the values being written to be
1963  * performed, and the mode field allows minimal authentication.
1964  *
1965  * More sophisticated management can be enabled by the provision of a
1966  * strategy routine with the table entry.  This will be called before
1967  * any automatic read or write of the data is performed.
1968  *
1969  * The strategy routine may return
1970  *
1971  * < 0 - Error occurred (error is passed to user process)
1972  *
1973  * 0   - OK - proceed with automatic read or write.
1974  *
1975  * > 0 - OK - read or write has been done by the strategy routine, so
1976  *       return immediately.
1977  *
1978  * There must be a proc_handler routine for any terminal nodes
1979  * mirrored under /proc/sys (non-terminals are handled by a built-in
1980  * directory handler).  Several default handlers are available to
1981  * cover common cases -
1982  *
1983  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1984  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1985  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1986  *
1987  * It is the handler's job to read the input buffer from user memory
1988  * and process it. The handler should return 0 on success.
1989  *
1990  * This routine returns %NULL on a failure to register, and a pointer
1991  * to the table header on success.
1992  */
1993 struct ctl_table_header *__register_sysctl_paths(
1994         struct ctl_table_root *root,
1995         struct nsproxy *namespaces,
1996         const struct ctl_path *path, struct ctl_table *table)
1997 {
1998         struct ctl_table_header *header;
1999         struct ctl_table *new, **prevp;
2000         unsigned int n, npath;
2001         struct ctl_table_set *set;
2002
2003         /* Count the path components */
2004         for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
2005                 ;
2006
2007         /*
2008          * For each path component, allocate a 2-element ctl_table array.
2009          * The first array element will be filled with the sysctl entry
2010          * for this, the second will be the sentinel (ctl_name == 0).
2011          *
2012          * We allocate everything in one go so that we don't have to
2013          * worry about freeing additional memory in unregister_sysctl_table.
2014          */
2015         header = kzalloc(sizeof(struct ctl_table_header) +
2016                          (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
2017         if (!header)
2018                 return NULL;
2019
2020         new = (struct ctl_table *) (header + 1);
2021
2022         /* Now connect the dots */
2023         prevp = &header->ctl_table;
2024         for (n = 0; n < npath; ++n, ++path) {
2025                 /* Copy the procname */
2026                 new->procname = path->procname;
2027                 new->ctl_name = path->ctl_name;
2028                 new->mode     = 0555;
2029
2030                 *prevp = new;
2031                 prevp = &new->child;
2032
2033                 new += 2;
2034         }
2035         *prevp = table;
2036         header->ctl_table_arg = table;
2037
2038         INIT_LIST_HEAD(&header->ctl_entry);
2039         header->used = 0;
2040         header->unregistering = NULL;
2041         header->root = root;
2042         sysctl_set_parent(NULL, header->ctl_table);
2043         header->count = 1;
2044 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2045         if (sysctl_check_table(namespaces, header->ctl_table)) {
2046                 kfree(header);
2047                 return NULL;
2048         }
2049 #endif
2050         spin_lock(&sysctl_lock);
2051         header->set = lookup_header_set(root, namespaces);
2052         header->attached_by = header->ctl_table;
2053         header->attached_to = root_table;
2054         header->parent = &root_table_header;
2055         for (set = header->set; set; set = set->parent) {
2056                 struct ctl_table_header *p;
2057                 list_for_each_entry(p, &set->list, ctl_entry) {
2058                         if (p->unregistering)
2059                                 continue;
2060                         try_attach(p, header);
2061                 }
2062         }
2063         header->parent->count++;
2064         list_add_tail(&header->ctl_entry, &header->set->list);
2065         spin_unlock(&sysctl_lock);
2066
2067         return header;
2068 }
2069
2070 /**
2071  * register_sysctl_table_path - register a sysctl table hierarchy
2072  * @path: The path to the directory the sysctl table is in.
2073  * @table: the top-level table structure
2074  *
2075  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2076  * array. A completely 0 filled entry terminates the table.
2077  *
2078  * See __register_sysctl_paths for more details.
2079  */
2080 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2081                                                 struct ctl_table *table)
2082 {
2083         return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2084                                         path, table);
2085 }
2086
2087 /**
2088  * register_sysctl_table - register a sysctl table hierarchy
2089  * @table: the top-level table structure
2090  *
2091  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2092  * array. A completely 0 filled entry terminates the table.
2093  *
2094  * See register_sysctl_paths for more details.
2095  */
2096 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2097 {
2098         static const struct ctl_path null_path[] = { {} };
2099
2100         return register_sysctl_paths(null_path, table);
2101 }
2102
2103 /**
2104  * unregister_sysctl_table - unregister a sysctl table hierarchy
2105  * @header: the header returned from register_sysctl_table
2106  *
2107  * Unregisters the sysctl table and all children. proc entries may not
2108  * actually be removed until they are no longer used by anyone.
2109  */
2110 void unregister_sysctl_table(struct ctl_table_header * header)
2111 {
2112         might_sleep();
2113
2114         if (header == NULL)
2115                 return;
2116
2117         spin_lock(&sysctl_lock);
2118         start_unregistering(header);
2119         if (!--header->parent->count) {
2120                 WARN_ON(1);
2121                 kfree(header->parent);
2122         }
2123         if (!--header->count)
2124                 kfree(header);
2125         spin_unlock(&sysctl_lock);
2126 }
2127
2128 int sysctl_is_seen(struct ctl_table_header *p)
2129 {
2130         struct ctl_table_set *set = p->set;
2131         int res;
2132         spin_lock(&sysctl_lock);
2133         if (p->unregistering)
2134                 res = 0;
2135         else if (!set->is_seen)
2136                 res = 1;
2137         else
2138                 res = set->is_seen(set);
2139         spin_unlock(&sysctl_lock);
2140         return res;
2141 }
2142
2143 void setup_sysctl_set(struct ctl_table_set *p,
2144         struct ctl_table_set *parent,
2145         int (*is_seen)(struct ctl_table_set *))
2146 {
2147         INIT_LIST_HEAD(&p->list);
2148         p->parent = parent ? parent : &sysctl_table_root.default_set;
2149         p->is_seen = is_seen;
2150 }
2151
2152 #else /* !CONFIG_SYSCTL */
2153 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2154 {
2155         return NULL;
2156 }
2157
2158 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2159                                                     struct ctl_table *table)
2160 {
2161         return NULL;
2162 }
2163
2164 void unregister_sysctl_table(struct ctl_table_header * table)
2165 {
2166 }
2167
2168 void setup_sysctl_set(struct ctl_table_set *p,
2169         struct ctl_table_set *parent,
2170         int (*is_seen)(struct ctl_table_set *))
2171 {
2172 }
2173
2174 void sysctl_head_put(struct ctl_table_header *head)
2175 {
2176 }
2177
2178 #endif /* CONFIG_SYSCTL */
2179
2180 /*
2181  * /proc/sys support
2182  */
2183
2184 #ifdef CONFIG_PROC_SYSCTL
2185
2186 static int _proc_do_string(void* data, int maxlen, int write,
2187                            struct file *filp, void __user *buffer,
2188                            size_t *lenp, loff_t *ppos)
2189 {
2190         size_t len;
2191         char __user *p;
2192         char c;
2193
2194         if (!data || !maxlen || !*lenp) {
2195                 *lenp = 0;
2196                 return 0;
2197         }
2198
2199         if (write) {
2200                 len = 0;
2201                 p = buffer;
2202                 while (len < *lenp) {
2203                         if (get_user(c, p++))
2204                                 return -EFAULT;
2205                         if (c == 0 || c == '\n')
2206                                 break;
2207                         len++;
2208                 }
2209                 if (len >= maxlen)
2210                         len = maxlen-1;
2211                 if(copy_from_user(data, buffer, len))
2212                         return -EFAULT;
2213                 ((char *) data)[len] = 0;
2214                 *ppos += *lenp;
2215         } else {
2216                 len = strlen(data);
2217                 if (len > maxlen)
2218                         len = maxlen;
2219
2220                 if (*ppos > len) {
2221                         *lenp = 0;
2222                         return 0;
2223                 }
2224
2225                 data += *ppos;
2226                 len  -= *ppos;
2227
2228                 if (len > *lenp)
2229                         len = *lenp;
2230                 if (len)
2231                         if(copy_to_user(buffer, data, len))
2232                                 return -EFAULT;
2233                 if (len < *lenp) {
2234                         if(put_user('\n', ((char __user *) buffer) + len))
2235                                 return -EFAULT;
2236                         len++;
2237                 }
2238                 *lenp = len;
2239                 *ppos += len;
2240         }
2241         return 0;
2242 }
2243
2244 /**
2245  * proc_dostring - read a string sysctl
2246  * @table: the sysctl table
2247  * @write: %TRUE if this is a write to the sysctl file
2248  * @filp: the file structure
2249  * @buffer: the user buffer
2250  * @lenp: the size of the user buffer
2251  * @ppos: file position
2252  *
2253  * Reads/writes a string from/to the user buffer. If the kernel
2254  * buffer provided is not large enough to hold the string, the
2255  * string is truncated. The copied string is %NULL-terminated.
2256  * If the string is being read by the user process, it is copied
2257  * and a newline '\n' is added. It is truncated if the buffer is
2258  * not large enough.
2259  *
2260  * Returns 0 on success.
2261  */
2262 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2263                   void __user *buffer, size_t *lenp, loff_t *ppos)
2264 {
2265         return _proc_do_string(table->data, table->maxlen, write, filp,
2266                                buffer, lenp, ppos);
2267 }
2268
2269
2270 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2271                                  int *valp,
2272                                  int write, void *data)
2273 {
2274         if (write) {
2275                 *valp = *negp ? -*lvalp : *lvalp;
2276         } else {
2277                 int val = *valp;
2278                 if (val < 0) {
2279                         *negp = -1;
2280                         *lvalp = (unsigned long)-val;
2281                 } else {
2282                         *negp = 0;
2283                         *lvalp = (unsigned long)val;
2284                 }
2285         }
2286         return 0;
2287 }
2288
2289 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2290                   int write, struct file *filp, void __user *buffer,
2291                   size_t *lenp, loff_t *ppos,
2292                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2293                               int write, void *data),
2294                   void *data)
2295 {
2296 #define TMPBUFLEN 21
2297         int *i, vleft, first = 1, neg;
2298         unsigned long lval;
2299         size_t left, len;
2300
2301         char buf[TMPBUFLEN], *p;
2302         char __user *s = buffer;
2303
2304         if (!tbl_data || !table->maxlen || !*lenp ||
2305             (*ppos && !write)) {
2306                 *lenp = 0;
2307                 return 0;
2308         }
2309
2310         i = (int *) tbl_data;
2311         vleft = table->maxlen / sizeof(*i);
2312         left = *lenp;
2313
2314         if (!conv)
2315                 conv = do_proc_dointvec_conv;
2316
2317         for (; left && vleft--; i++, first=0) {
2318                 if (write) {
2319                         while (left) {
2320                                 char c;
2321                                 if (get_user(c, s))
2322                                         return -EFAULT;
2323                                 if (!isspace(c))
2324                                         break;
2325                                 left--;
2326                                 s++;
2327                         }
2328                         if (!left)
2329                                 break;
2330                         neg = 0;
2331                         len = left;
2332                         if (len > sizeof(buf) - 1)
2333                                 len = sizeof(buf) - 1;
2334                         if (copy_from_user(buf, s, len))
2335                                 return -EFAULT;
2336                         buf[len] = 0;
2337                         p = buf;
2338                         if (*p == '-' && left > 1) {
2339                                 neg = 1;
2340                                 p++;
2341                         }
2342                         if (*p < '0' || *p > '9')
2343                                 break;
2344
2345                         lval = simple_strtoul(p, &p, 0);
2346
2347                         len = p-buf;
2348                         if ((len < left) && *p && !isspace(*p))
2349                                 break;
2350                         s += len;
2351                         left -= len;
2352
2353                         if (conv(&neg, &lval, i, 1, data))
2354                                 break;
2355                 } else {
2356                         p = buf;
2357                         if (!first)
2358                                 *p++ = '\t';
2359
2360                         if (conv(&neg, &lval, i, 0, data))
2361                                 break;
2362
2363                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
2364                         len = strlen(buf);
2365                         if (len > left)
2366                                 len = left;
2367                         if(copy_to_user(s, buf, len))
2368                                 return -EFAULT;
2369                         left -= len;
2370                         s += len;
2371                 }
2372         }
2373
2374         if (!write && !first && left) {
2375                 if(put_user('\n', s))
2376                         return -EFAULT;
2377                 left--, s++;
2378         }
2379         if (write) {
2380                 while (left) {
2381                         char c;
2382                         if (get_user(c, s++))
2383                                 return -EFAULT;
2384                         if (!isspace(c))
2385                                 break;
2386                         left--;
2387                 }
2388         }
2389         if (write && first)
2390                 return -EINVAL;
2391         *lenp -= left;
2392         *ppos += *lenp;
2393         return 0;
2394 #undef TMPBUFLEN
2395 }
2396
2397 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2398                   void __user *buffer, size_t *lenp, loff_t *ppos,
2399                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2400                               int write, void *data),
2401                   void *data)
2402 {
2403         return __do_proc_dointvec(table->data, table, write, filp,
2404                         buffer, lenp, ppos, conv, data);
2405 }
2406
2407 /**
2408  * proc_dointvec - read a vector of integers
2409  * @table: the sysctl table
2410  * @write: %TRUE if this is a write to the sysctl file
2411  * @filp: the file structure
2412  * @buffer: the user buffer
2413  * @lenp: the size of the user buffer
2414  * @ppos: file position
2415  *
2416  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2417  * values from/to the user buffer, treated as an ASCII string.
2418  *
2419  * Returns 0 on success.
2420  */
2421 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2422                      void __user *buffer, size_t *lenp, loff_t *ppos)
2423 {
2424     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2425                             NULL,NULL);
2426 }
2427
2428 /*
2429  * Taint values can only be increased
2430  * This means we can safely use a temporary.
2431  */
2432 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2433                                void __user *buffer, size_t *lenp, loff_t *ppos)
2434 {
2435         struct ctl_table t;
2436         unsigned long tmptaint = get_taint();
2437         int err;
2438
2439         if (write && !capable(CAP_SYS_ADMIN))
2440                 return -EPERM;
2441
2442         t = *table;
2443         t.data = &tmptaint;
2444         err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2445         if (err < 0)
2446                 return err;
2447
2448         if (write) {
2449                 /*
2450                  * Poor man's atomic or. Not worth adding a primitive
2451                  * to everyone's atomic.h for this
2452                  */
2453                 int i;
2454                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2455                         if ((tmptaint >> i) & 1)
2456                                 add_taint(i);
2457                 }
2458         }
2459
2460         return err;
2461 }
2462
2463 struct do_proc_dointvec_minmax_conv_param {
2464         int *min;
2465         int *max;
2466 };
2467
2468 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2469                                         int *valp,
2470                                         int write, void *data)
2471 {
2472         struct do_proc_dointvec_minmax_conv_param *param = data;
2473         if (write) {
2474                 int val = *negp ? -*lvalp : *lvalp;
2475                 if ((param->min && *param->min > val) ||
2476                     (param->max && *param->max < val))
2477                         return -EINVAL;
2478                 *valp = val;
2479         } else {
2480                 int val = *valp;
2481                 if (val < 0) {
2482                         *negp = -1;
2483                         *lvalp = (unsigned long)-val;
2484                 } else {
2485                         *negp = 0;
2486                         *lvalp = (unsigned long)val;
2487                 }
2488         }
2489         return 0;
2490 }
2491
2492 /**
2493  * proc_dointvec_minmax - read a vector of integers with min/max values
2494  * @table: the sysctl table
2495  * @write: %TRUE if this is a write to the sysctl file
2496  * @filp: the file structure
2497  * @buffer: the user buffer
2498  * @lenp: the size of the user buffer
2499  * @ppos: file position
2500  *
2501  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2502  * values from/to the user buffer, treated as an ASCII string.
2503  *
2504  * This routine will ensure the values are within the range specified by
2505  * table->extra1 (min) and table->extra2 (max).
2506  *
2507  * Returns 0 on success.
2508  */
2509 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2510                   void __user *buffer, size_t *lenp, loff_t *ppos)
2511 {
2512         struct do_proc_dointvec_minmax_conv_param param = {
2513                 .min = (int *) table->extra1,
2514                 .max = (int *) table->extra2,
2515         };
2516         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2517                                 do_proc_dointvec_minmax_conv, &param);
2518 }
2519
2520 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2521                                      struct file *filp,
2522                                      void __user *buffer,
2523                                      size_t *lenp, loff_t *ppos,
2524                                      unsigned long convmul,
2525                                      unsigned long convdiv)
2526 {
2527 #define TMPBUFLEN 21
2528         unsigned long *i, *min, *max, val;
2529         int vleft, first=1, neg;
2530         size_t len, left;
2531         char buf[TMPBUFLEN], *p;
2532         char __user *s = buffer;
2533
2534         if (!data || !table->maxlen || !*lenp ||
2535             (*ppos && !write)) {
2536                 *lenp = 0;
2537                 return 0;
2538         }
2539
2540         i = (unsigned long *) data;
2541         min = (unsigned long *) table->extra1;
2542         max = (unsigned long *) table->extra2;
2543         vleft = table->maxlen / sizeof(unsigned long);
2544         left = *lenp;
2545
2546         for (; left && vleft--; i++, min++, max++, first=0) {
2547                 if (write) {
2548                         while (left) {
2549                                 char c;
2550                                 if (get_user(c, s))
2551                                         return -EFAULT;
2552                                 if (!isspace(c))
2553                                         break;
2554                                 left--;
2555                                 s++;
2556                         }
2557                         if (!left)
2558                                 break;
2559                         neg = 0;
2560                         len = left;
2561                         if (len > TMPBUFLEN-1)
2562                                 len = TMPBUFLEN-1;
2563                         if (copy_from_user(buf, s, len))
2564                                 return -EFAULT;
2565                         buf[len] = 0;
2566                         p = buf;
2567                         if (*p == '-' && left > 1) {
2568                                 neg = 1;
2569                                 p++;
2570                         }
2571                         if (*p < '0' || *p > '9')
2572                                 break;
2573                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2574                         len = p-buf;
2575                         if ((len < left) && *p && !isspace(*p))
2576                                 break;
2577                         if (neg)
2578                                 val = -val;
2579                         s += len;
2580                         left -= len;
2581
2582                         if(neg)
2583                                 continue;
2584                         if ((min && val < *min) || (max && val > *max))
2585                                 continue;
2586                         *i = val;
2587                 } else {
2588                         p = buf;
2589                         if (!first)
2590                                 *p++ = '\t';
2591                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2592                         len = strlen(buf);
2593                         if (len > left)
2594                                 len = left;
2595                         if(copy_to_user(s, buf, len))
2596                                 return -EFAULT;
2597                         left -= len;
2598                         s += len;
2599                 }
2600         }
2601
2602         if (!write && !first && left) {
2603                 if(put_user('\n', s))
2604                         return -EFAULT;
2605                 left--, s++;
2606         }
2607         if (write) {
2608                 while (left) {
2609                         char c;
2610                         if (get_user(c, s++))
2611                                 return -EFAULT;
2612                         if (!isspace(c))
2613                                 break;
2614                         left--;
2615                 }
2616         }
2617         if (write && first)
2618                 return -EINVAL;
2619         *lenp -= left;
2620         *ppos += *lenp;
2621         return 0;
2622 #undef TMPBUFLEN
2623 }
2624
2625 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2626                                      struct file *filp,
2627                                      void __user *buffer,
2628                                      size_t *lenp, loff_t *ppos,
2629                                      unsigned long convmul,
2630                                      unsigned long convdiv)
2631 {
2632         return __do_proc_doulongvec_minmax(table->data, table, write,
2633                         filp, buffer, lenp, ppos, convmul, convdiv);
2634 }
2635
2636 /**
2637  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2638  * @table: the sysctl table
2639  * @write: %TRUE if this is a write to the sysctl file
2640  * @filp: the file structure
2641  * @buffer: the user buffer
2642  * @lenp: the size of the user buffer
2643  * @ppos: file position
2644  *
2645  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2646  * values from/to the user buffer, treated as an ASCII string.
2647  *
2648  * This routine will ensure the values are within the range specified by
2649  * table->extra1 (min) and table->extra2 (max).
2650  *
2651  * Returns 0 on success.
2652  */
2653 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2654                            void __user *buffer, size_t *lenp, loff_t *ppos)
2655 {
2656     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2657 }
2658
2659 /**
2660  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2661  * @table: the sysctl table
2662  * @write: %TRUE if this is a write to the sysctl file
2663  * @filp: the file structure
2664  * @buffer: the user buffer
2665  * @lenp: the size of the user buffer
2666  * @ppos: file position
2667  *
2668  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2669  * values from/to the user buffer, treated as an ASCII string. The values
2670  * are treated as milliseconds, and converted to jiffies when they are stored.
2671  *
2672  * This routine will ensure the values are within the range specified by
2673  * table->extra1 (min) and table->extra2 (max).
2674  *
2675  * Returns 0 on success.
2676  */
2677 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2678                                       struct file *filp,
2679                                       void __user *buffer,
2680                                       size_t *lenp, loff_t *ppos)
2681 {
2682     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2683                                      lenp, ppos, HZ, 1000l);
2684 }
2685
2686
2687 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2688                                          int *valp,
2689                                          int write, void *data)
2690 {
2691         if (write) {
2692                 if (*lvalp > LONG_MAX / HZ)
2693                         return 1;
2694                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2695         } else {
2696                 int val = *valp;
2697                 unsigned long lval;
2698                 if (val < 0) {
2699                         *negp = -1;
2700                         lval = (unsigned long)-val;
2701                 } else {
2702                         *negp = 0;
2703                         lval = (unsigned long)val;
2704                 }
2705                 *lvalp = lval / HZ;
2706         }
2707         return 0;
2708 }
2709
2710 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2711                                                 int *valp,
2712                                                 int write, void *data)
2713 {
2714         if (write) {
2715                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2716                         return 1;
2717                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2718         } else {
2719                 int val = *valp;
2720                 unsigned long lval;
2721                 if (val < 0) {
2722                         *negp = -1;
2723                         lval = (unsigned long)-val;
2724                 } else {
2725                         *negp = 0;
2726                         lval = (unsigned long)val;
2727                 }
2728                 *lvalp = jiffies_to_clock_t(lval);
2729         }
2730         return 0;
2731 }
2732
2733 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2734                                             int *valp,
2735                                             int write, void *data)
2736 {
2737         if (write) {
2738                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2739         } else {
2740                 int val = *valp;
2741                 unsigned long lval;
2742                 if (val < 0) {
2743                         *negp = -1;
2744                         lval = (unsigned long)-val;
2745                 } else {
2746                         *negp = 0;
2747                         lval = (unsigned long)val;
2748                 }
2749                 *lvalp = jiffies_to_msecs(lval);
2750         }
2751         return 0;
2752 }
2753
2754 /**
2755  * proc_dointvec_jiffies - read a vector of integers as seconds
2756  * @table: the sysctl table
2757  * @write: %TRUE if this is a write to the sysctl file
2758  * @filp: the file structure
2759  * @buffer: the user buffer
2760  * @lenp: the size of the user buffer
2761  * @ppos: file position
2762  *
2763  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2764  * values from/to the user buffer, treated as an ASCII string.
2765  * The values read are assumed to be in seconds, and are converted into
2766  * jiffies.
2767  *
2768  * Returns 0 on success.
2769  */
2770 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2771                           void __user *buffer, size_t *lenp, loff_t *ppos)
2772 {
2773     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2774                             do_proc_dointvec_jiffies_conv,NULL);
2775 }
2776
2777 /**
2778  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2779  * @table: the sysctl table
2780  * @write: %TRUE if this is a write to the sysctl file
2781  * @filp: the file structure
2782  * @buffer: the user buffer
2783  * @lenp: the size of the user buffer
2784  * @ppos: pointer to the file position
2785  *
2786  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2787  * values from/to the user buffer, treated as an ASCII string.
2788  * The values read are assumed to be in 1/USER_HZ seconds, and
2789  * are converted into jiffies.
2790  *
2791  * Returns 0 on success.
2792  */
2793 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2794                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2795 {
2796     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2797                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2798 }
2799
2800 /**
2801  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2802  * @table: the sysctl table
2803  * @write: %TRUE if this is a write to the sysctl file
2804  * @filp: the file structure
2805  * @buffer: the user buffer
2806  * @lenp: the size of the user buffer
2807  * @ppos: file position
2808  * @ppos: the current position in the file
2809  *
2810  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2811  * values from/to the user buffer, treated as an ASCII string.
2812  * The values read are assumed to be in 1/1000 seconds, and
2813  * are converted into jiffies.
2814  *
2815  * Returns 0 on success.
2816  */
2817 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2818                              void __user *buffer, size_t *lenp, loff_t *ppos)
2819 {
2820         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2821                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2822 }
2823
2824 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2825                            void __user *buffer, size_t *lenp, loff_t *ppos)
2826 {
2827         struct pid *new_pid;
2828         pid_t tmp;
2829         int r;
2830
2831         tmp = pid_vnr(cad_pid);
2832
2833         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2834                                lenp, ppos, NULL, NULL);
2835         if (r || !write)
2836                 return r;
2837
2838         new_pid = find_get_pid(tmp);
2839         if (!new_pid)
2840                 return -ESRCH;
2841
2842         put_pid(xchg(&cad_pid, new_pid));
2843         return 0;
2844 }
2845
2846 #else /* CONFIG_PROC_FS */
2847
2848 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2849                   void __user *buffer, size_t *lenp, loff_t *ppos)
2850 {
2851         return -ENOSYS;
2852 }
2853
2854 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2855                   void __user *buffer, size_t *lenp, loff_t *ppos)
2856 {
2857         return -ENOSYS;
2858 }
2859
2860 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2861                     void __user *buffer, size_t *lenp, loff_t *ppos)
2862 {
2863         return -ENOSYS;
2864 }
2865
2866 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2867                     void __user *buffer, size_t *lenp, loff_t *ppos)
2868 {
2869         return -ENOSYS;
2870 }
2871
2872 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2873                     void __user *buffer, size_t *lenp, loff_t *ppos)
2874 {
2875         return -ENOSYS;
2876 }
2877
2878 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2879                              void __user *buffer, size_t *lenp, loff_t *ppos)
2880 {
2881         return -ENOSYS;
2882 }
2883
2884 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2885                     void __user *buffer, size_t *lenp, loff_t *ppos)
2886 {
2887         return -ENOSYS;
2888 }
2889
2890 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2891                                       struct file *filp,
2892                                       void __user *buffer,
2893                                       size_t *lenp, loff_t *ppos)
2894 {
2895     return -ENOSYS;
2896 }
2897
2898
2899 #endif /* CONFIG_PROC_FS */
2900
2901
2902 #ifdef CONFIG_SYSCTL_SYSCALL
2903 /*
2904  * General sysctl support routines
2905  */
2906
2907 /* The generic sysctl data routine (used if no strategy routine supplied) */
2908 int sysctl_data(struct ctl_table *table,
2909                 void __user *oldval, size_t __user *oldlenp,
2910                 void __user *newval, size_t newlen)
2911 {
2912         size_t len;
2913
2914         /* Get out of I don't have a variable */
2915         if (!table->data || !table->maxlen)
2916                 return -ENOTDIR;
2917
2918         if (oldval && oldlenp) {
2919                 if (get_user(len, oldlenp))
2920                         return -EFAULT;
2921                 if (len) {
2922                         if (len > table->maxlen)
2923                                 len = table->maxlen;
2924                         if (copy_to_user(oldval, table->data, len))
2925                                 return -EFAULT;
2926                         if (put_user(len, oldlenp))
2927                                 return -EFAULT;
2928                 }
2929         }
2930
2931         if (newval && newlen) {
2932                 if (newlen > table->maxlen)
2933                         newlen = table->maxlen;
2934
2935                 if (copy_from_user(table->data, newval, newlen))
2936                         return -EFAULT;
2937         }
2938         return 1;
2939 }
2940
2941 /* The generic string strategy routine: */
2942 int sysctl_string(struct ctl_table *table,
2943                   void __user *oldval, size_t __user *oldlenp,
2944                   void __user *newval, size_t newlen)
2945 {
2946         if (!table->data || !table->maxlen)
2947                 return -ENOTDIR;
2948
2949         if (oldval && oldlenp) {
2950                 size_t bufsize;
2951                 if (get_user(bufsize, oldlenp))
2952                         return -EFAULT;
2953                 if (bufsize) {
2954                         size_t len = strlen(table->data), copied;
2955
2956                         /* This shouldn't trigger for a well-formed sysctl */
2957                         if (len > table->maxlen)
2958                                 len = table->maxlen;
2959
2960                         /* Copy up to a max of bufsize-1 bytes of the string */
2961                         copied = (len >= bufsize) ? bufsize - 1 : len;
2962
2963                         if (copy_to_user(oldval, table->data, copied) ||
2964                             put_user(0, (char __user *)(oldval + copied)))
2965                                 return -EFAULT;
2966                         if (put_user(len, oldlenp))
2967                                 return -EFAULT;
2968                 }
2969         }
2970         if (newval && newlen) {
2971                 size_t len = newlen;
2972                 if (len > table->maxlen)
2973                         len = table->maxlen;
2974                 if(copy_from_user(table->data, newval, len))
2975                         return -EFAULT;
2976                 if (len == table->maxlen)
2977                         len--;
2978                 ((char *) table->data)[len] = 0;
2979         }
2980         return 1;
2981 }
2982
2983 /*
2984  * This function makes sure that all of the integers in the vector
2985  * are between the minimum and maximum values given in the arrays
2986  * table->extra1 and table->extra2, respectively.
2987  */
2988 int sysctl_intvec(struct ctl_table *table,
2989                 void __user *oldval, size_t __user *oldlenp,
2990                 void __user *newval, size_t newlen)
2991 {
2992
2993         if (newval && newlen) {
2994                 int __user *vec = (int __user *) newval;
2995                 int *min = (int *) table->extra1;
2996                 int *max = (int *) table->extra2;
2997                 size_t length;
2998                 int i;
2999
3000                 if (newlen % sizeof(int) != 0)
3001                         return -EINVAL;
3002
3003                 if (!table->extra1 && !table->extra2)
3004                         return 0;
3005
3006                 if (newlen > table->maxlen)
3007                         newlen = table->maxlen;
3008                 length = newlen / sizeof(int);
3009
3010                 for (i = 0; i < length; i++) {
3011                         int value;
3012                         if (get_user(value, vec + i))
3013                                 return -EFAULT;
3014                         if (min && value < min[i])
3015                                 return -EINVAL;
3016                         if (max && value > max[i])
3017                                 return -EINVAL;
3018                 }
3019         }
3020         return 0;
3021 }
3022
3023 /* Strategy function to convert jiffies to seconds */
3024 int sysctl_jiffies(struct ctl_table *table,
3025                 void __user *oldval, size_t __user *oldlenp,
3026                 void __user *newval, size_t newlen)
3027 {
3028         if (oldval && oldlenp) {
3029                 size_t olen;
3030
3031                 if (get_user(olen, oldlenp))
3032                         return -EFAULT;
3033                 if (olen) {
3034                         int val;
3035
3036                         if (olen < sizeof(int))
3037                                 return -EINVAL;
3038
3039                         val = *(int *)(table->data) / HZ;
3040                         if (put_user(val, (int __user *)oldval))
3041                                 return -EFAULT;
3042                         if (put_user(sizeof(int), oldlenp))
3043                                 return -EFAULT;
3044                 }
3045         }
3046         if (newval && newlen) {
3047                 int new;
3048                 if (newlen != sizeof(int))
3049                         return -EINVAL;
3050                 if (get_user(new, (int __user *)newval))
3051                         return -EFAULT;
3052                 *(int *)(table->data) = new*HZ;
3053         }
3054         return 1;
3055 }
3056
3057 /* Strategy function to convert jiffies to seconds */
3058 int sysctl_ms_jiffies(struct ctl_table *table,
3059                 void __user *oldval, size_t __user *oldlenp,
3060                 void __user *newval, size_t newlen)
3061 {
3062         if (oldval && oldlenp) {
3063                 size_t olen;
3064
3065                 if (get_user(olen, oldlenp))
3066                         return -EFAULT;
3067                 if (olen) {
3068                         int val;
3069
3070                         if (olen < sizeof(int))
3071                                 return -EINVAL;
3072
3073                         val = jiffies_to_msecs(*(int *)(table->data));
3074                         if (put_user(val, (int __user *)oldval))
3075                                 return -EFAULT;
3076                         if (put_user(sizeof(int), oldlenp))
3077                                 return -EFAULT;
3078                 }
3079         }
3080         if (newval && newlen) {
3081                 int new;
3082                 if (newlen != sizeof(int))
3083                         return -EINVAL;
3084                 if (get_user(new, (int __user *)newval))
3085                         return -EFAULT;
3086                 *(int *)(table->data) = msecs_to_jiffies(new);
3087         }
3088         return 1;
3089 }
3090
3091
3092
3093 #else /* CONFIG_SYSCTL_SYSCALL */
3094
3095
3096 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3097 {
3098         struct __sysctl_args tmp;
3099         int error;
3100
3101         if (copy_from_user(&tmp, args, sizeof(tmp)))
3102                 return -EFAULT;
3103
3104         error = deprecated_sysctl_warning(&tmp);
3105
3106         /* If no error reading the parameters then just -ENOSYS ... */
3107         if (!error)
3108                 error = -ENOSYS;
3109
3110         return error;
3111 }
3112
3113 int sysctl_data(struct ctl_table *table,
3114                   void __user *oldval, size_t __user *oldlenp,
3115                   void __user *newval, size_t newlen)
3116 {
3117         return -ENOSYS;
3118 }
3119
3120 int sysctl_string(struct ctl_table *table,
3121                   void __user *oldval, size_t __user *oldlenp,
3122                   void __user *newval, size_t newlen)
3123 {
3124         return -ENOSYS;
3125 }
3126
3127 int sysctl_intvec(struct ctl_table *table,
3128                 void __user *oldval, size_t __user *oldlenp,
3129                 void __user *newval, size_t newlen)
3130 {
3131         return -ENOSYS;
3132 }
3133
3134 int sysctl_jiffies(struct ctl_table *table,
3135                 void __user *oldval, size_t __user *oldlenp,
3136                 void __user *newval, size_t newlen)
3137 {
3138         return -ENOSYS;
3139 }
3140
3141 int sysctl_ms_jiffies(struct ctl_table *table,
3142                 void __user *oldval, size_t __user *oldlenp,
3143                 void __user *newval, size_t newlen)
3144 {
3145         return -ENOSYS;
3146 }
3147
3148 #endif /* CONFIG_SYSCTL_SYSCALL */
3149
3150 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3151 {
3152         static int msg_count;
3153         int name[CTL_MAXNAME];
3154         int i;
3155
3156         /* Check args->nlen. */
3157         if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3158                 return -ENOTDIR;
3159
3160         /* Read in the sysctl name for better debug message logging */
3161         for (i = 0; i < args->nlen; i++)
3162                 if (get_user(name[i], args->name + i))
3163                         return -EFAULT;
3164
3165         /* Ignore accesses to kernel.version */
3166         if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3167                 return 0;
3168
3169         if (msg_count < 5) {
3170                 msg_count++;
3171                 printk(KERN_INFO
3172                         "warning: process `%s' used the deprecated sysctl "
3173                         "system call with ", current->comm);
3174                 for (i = 0; i < args->nlen; i++)
3175                         printk("%d.", name[i]);
3176                 printk("\n");
3177         }
3178         return 0;
3179 }
3180
3181 /*
3182  * No sense putting this after each symbol definition, twice,
3183  * exception granted :-)
3184  */
3185 EXPORT_SYMBOL(proc_dointvec);
3186 EXPORT_SYMBOL(proc_dointvec_jiffies);
3187 EXPORT_SYMBOL(proc_dointvec_minmax);
3188 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3189 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3190 EXPORT_SYMBOL(proc_dostring);
3191 EXPORT_SYMBOL(proc_doulongvec_minmax);
3192 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3193 EXPORT_SYMBOL(register_sysctl_table);
3194 EXPORT_SYMBOL(register_sysctl_paths);
3195 EXPORT_SYMBOL(sysctl_intvec);
3196 EXPORT_SYMBOL(sysctl_jiffies);
3197 EXPORT_SYMBOL(sysctl_ms_jiffies);
3198 EXPORT_SYMBOL(sysctl_string);
3199 EXPORT_SYMBOL(sysctl_data);
3200 EXPORT_SYMBOL(unregister_sysctl_table);