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/kmemcheck.h>
  30 #include <linux/fs.h>
  31 #include <linux/init.h>
  32 #include <linux/kernel.h>
  33 #include <linux/kobject.h>
  34 #include <linux/net.h>
  35 #include <linux/sysrq.h>
  36 #include <linux/highuid.h>
  37 #include <linux/writeback.h>
  38 #include <linux/ratelimit.h>
  39 #include <linux/hugetlb.h>
  40 #include <linux/initrd.h>
  41 #include <linux/key.h>
  42 #include <linux/times.h>
  43 #include <linux/limits.h>
  44 #include <linux/dcache.h>
  45 #include <linux/syscalls.h>
  46 #include <linux/vmstat.h>
  47 #include <linux/nfs_fs.h>
  48 #include <linux/acpi.h>
  49 #include <linux/reboot.h>
  50 #include <linux/ftrace.h>
  51 #include <linux/slow-work.h>
  52 #include <linux/perf_event.h>
  53 #include <linux/kprobes.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
  65 #if defined(CONFIG_SYSCTL)
  66
  67 /* External variables not in a header file. */
  68 extern int C_A_D;
  69 extern int print_fatal_signals;
  70 extern int sysctl_overcommit_memory;
  71 extern int sysctl_overcommit_ratio;
  72 extern int sysctl_panic_on_oom;
  73 extern int sysctl_oom_kill_allocating_task;
  74 extern int sysctl_oom_dump_tasks;
  75 extern int max_threads;
  76 extern int core_uses_pid;
  77 extern int suid_dumpable;
  78 extern char core_pattern[];
  79 extern unsigned int core_pipe_limit;
  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 #ifdef CONFIG_BLOCK
  95 extern int blk_iopoll_enabled;
  96 #endif
  97
  98 /* Constants used for minimum and  maximum */
  99 #ifdef CONFIG_DETECT_SOFTLOCKUP
 100 static int sixty = 60;
 101 static int neg_one = -1;
 102 #endif
 103
 104 static int zero;
 105 static int __maybe_unused one = 1;
 106 static int __maybe_unused two = 2;
 107 static unsigned long one_ul = 1;
 108 static int one_hundred = 100;
 109 #ifdef CONFIG_PRINTK
 110 static int ten_thousand = 10000;
 111 #endif
 112
 113 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
 114 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
 115
 116 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 117 static int maxolduid = 65535;
 118 static int minolduid;
 119 static int min_percpu_pagelist_fract = 8;
 120
 121 static int ngroups_max = NGROUPS_MAX;
 122
 123 #ifdef CONFIG_MODULES
 124 extern char modprobe_path[];
 125 extern int modules_disabled;
 126 #endif
 127 #ifdef CONFIG_CHR_DEV_SG
 128 extern int sg_big_buff;
 129 #endif
 130
 131 #ifdef CONFIG_SPARC
 132 #include <asm/system.h>
 133 #endif
 134
 135 #ifdef CONFIG_SPARC64
 136 extern int sysctl_tsb_ratio;
 137 #endif
 138
 139 #ifdef __hppa__
 140 extern int pwrsw_enabled;
 141 extern int unaligned_enabled;
 142 #endif
 143
 144 #ifdef CONFIG_S390
 145 #ifdef CONFIG_MATHEMU
 146 extern int sysctl_ieee_emulation_warnings;
 147 #endif
 148 extern int sysctl_userprocess_debug;
 149 extern int spin_retry;
 150 #endif
 151
 152 #ifdef CONFIG_BSD_PROCESS_ACCT
 153 extern int acct_parm[];
 154 #endif
 155
 156 #ifdef CONFIG_IA64
 157 extern int no_unaligned_warning;
 158 extern int unaligned_dump_stack;
 159 #endif
 160
 161 extern struct ratelimit_state printk_ratelimit_state;
 162
 163 #ifdef CONFIG_RT_MUTEXES
 164 extern int max_lock_depth;
 165 #endif
 166
 167 #ifdef CONFIG_PROC_SYSCTL
 168 static int proc_do_cad_pid(struct ctl_table *table, int write,
 169                   void __user *buffer, size_t *lenp, loff_t *ppos);
 170 static int proc_taint(struct ctl_table *table, int write,
 171                                void __user *buffer, size_t *lenp, loff_t *ppos);
 172 #endif
 173
 174 static struct ctl_table root_table[];
 175 static struct ctl_table_root sysctl_table_root;
 176 static struct ctl_table_header root_table_header = {
 177         .count = 1,
 178         .ctl_table = root_table,
 179         .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
 180         .root = &sysctl_table_root,
 181         .set = &sysctl_table_root.default_set,
 182 };
 183 static struct ctl_table_root sysctl_table_root = {
 184         .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
 185         .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
 186 };
 187
 188 static struct ctl_table kern_table[];
 189 static struct ctl_table vm_table[];
 190 static struct ctl_table fs_table[];
 191 static struct ctl_table debug_table[];
 192 static struct ctl_table dev_table[];
 193 extern struct ctl_table random_table[];
 194 #ifdef CONFIG_INOTIFY_USER
 195 extern struct ctl_table inotify_table[];
 196 #endif
 197 #ifdef CONFIG_EPOLL
 198 extern struct ctl_table epoll_table[];
 199 #endif
 200
 201 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 202 int sysctl_legacy_va_layout;
 203 #endif
 204
 205 extern int prove_locking;
 206 extern int lock_stat;
 207
 208 /* The default sysctl tables: */
 209
 210 static struct ctl_table root_table[] = {
 211         {
 212                 .procname       = "kernel",
 213                 .mode           = 0555,
 214                 .child          = kern_table,
 215         },
 216         {
 217                 .procname       = "vm",
 218                 .mode           = 0555,
 219                 .child          = vm_table,
 220         },
 221         {
 222                 .procname       = "fs",
 223                 .mode           = 0555,
 224                 .child          = fs_table,
 225         },
 226         {
 227                 .procname       = "debug",
 228                 .mode           = 0555,
 229                 .child          = debug_table,
 230         },
 231         {
 232                 .procname       = "dev",
 233                 .mode           = 0555,
 234                 .child          = dev_table,
 235         },
 236 /*
 237  * NOTE: do not add new entries to this table unless you have read
 238  * Documentation/sysctl/ctl_unnumbered.txt
 239  */
 240         { }
 241 };
 242
 243 #ifdef CONFIG_SCHED_DEBUG
 244 static int min_sched_granularity_ns = 100000;           /* 100 usecs */
 245 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
 246 static int min_wakeup_granularity_ns;                   /* 0 usecs */
 247 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
 248 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
 249 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
 250 static int min_sched_shares_ratelimit = 100000; /* 100 usec */
 251 static int max_sched_shares_ratelimit = NSEC_PER_SEC; /* 1 second */
 252 #endif
 253
 254 static struct ctl_table kern_table[] = {
 255         {
 256                 .procname       = "sched_child_runs_first",
 257                 .data           = &sysctl_sched_child_runs_first,
 258                 .maxlen         = sizeof(unsigned int),
 259                 .mode           = 0644,
 260                 .proc_handler   = proc_dointvec,
 261         },
 262 #ifdef CONFIG_SCHED_DEBUG
 263         {
 264                 .procname       = "sched_min_granularity_ns",
 265                 .data           = &sysctl_sched_min_granularity,
 266                 .maxlen         = sizeof(unsigned int),
 267                 .mode           = 0644,
 268                 .proc_handler   = sched_proc_update_handler,
 269                 .extra1         = &min_sched_granularity_ns,
 270                 .extra2         = &max_sched_granularity_ns,
 271         },
 272         {
 273                 .procname       = "sched_latency_ns",
 274                 .data           = &sysctl_sched_latency,
 275                 .maxlen         = sizeof(unsigned int),
 276                 .mode           = 0644,
 277                 .proc_handler   = sched_proc_update_handler,
 278                 .extra1         = &min_sched_granularity_ns,
 279                 .extra2         = &max_sched_granularity_ns,
 280         },
 281         {
 282                 .procname       = "sched_wakeup_granularity_ns",
 283                 .data           = &sysctl_sched_wakeup_granularity,
 284                 .maxlen         = sizeof(unsigned int),
 285                 .mode           = 0644,
 286                 .proc_handler   = sched_proc_update_handler,
 287                 .extra1         = &min_wakeup_granularity_ns,
 288                 .extra2         = &max_wakeup_granularity_ns,
 289         },
 290         {
 291                 .procname       = "sched_shares_ratelimit",
 292                 .data           = &sysctl_sched_shares_ratelimit,
 293                 .maxlen         = sizeof(unsigned int),
 294                 .mode           = 0644,
 295                 .proc_handler   = sched_proc_update_handler,
 296                 .extra1         = &min_sched_shares_ratelimit,
 297                 .extra2         = &max_sched_shares_ratelimit,
 298         },
 299         {
 300                 .procname       = "sched_tunable_scaling",
 301                 .data           = &sysctl_sched_tunable_scaling,
 302                 .maxlen         = sizeof(enum sched_tunable_scaling),
 303                 .mode           = 0644,
 304                 .proc_handler   = sched_proc_update_handler,
 305                 .extra1         = &min_sched_tunable_scaling,
 306                 .extra2         = &max_sched_tunable_scaling,
 307         },
 308         {
 309                 .procname       = "sched_shares_thresh",
 310                 .data           = &sysctl_sched_shares_thresh,
 311                 .maxlen         = sizeof(unsigned int),
 312                 .mode           = 0644,
 313                 .proc_handler   = proc_dointvec_minmax,
 314                 .extra1         = &zero,
 315         },
 316         {
 317                 .procname       = "sched_migration_cost",
 318                 .data           = &sysctl_sched_migration_cost,
 319                 .maxlen         = sizeof(unsigned int),
 320                 .mode           = 0644,
 321                 .proc_handler   = proc_dointvec,
 322         },
 323         {
 324                 .procname       = "sched_nr_migrate",
 325                 .data           = &sysctl_sched_nr_migrate,
 326                 .maxlen         = sizeof(unsigned int),
 327                 .mode           = 0644,
 328                 .proc_handler   = proc_dointvec,
 329         },
 330         {
 331                 .procname       = "sched_time_avg",
 332                 .data           = &sysctl_sched_time_avg,
 333                 .maxlen         = sizeof(unsigned int),
 334                 .mode           = 0644,
 335                 .proc_handler   = proc_dointvec,
 336         },
 337         {
 338                 .procname       = "timer_migration",
 339                 .data           = &sysctl_timer_migration,
 340                 .maxlen         = sizeof(unsigned int),
 341                 .mode           = 0644,
 342                 .proc_handler   = proc_dointvec_minmax,
 343                 .extra1         = &zero,
 344                 .extra2         = &one,
 345         },
 346 #endif
 347         {
 348                 .procname       = "sched_rt_period_us",
 349                 .data           = &sysctl_sched_rt_period,
 350                 .maxlen         = sizeof(unsigned int),
 351                 .mode           = 0644,
 352                 .proc_handler   = sched_rt_handler,
 353         },
 354         {
 355                 .procname       = "sched_rt_runtime_us",
 356                 .data           = &sysctl_sched_rt_runtime,
 357                 .maxlen         = sizeof(int),
 358                 .mode           = 0644,
 359                 .proc_handler   = sched_rt_handler,
 360         },
 361         {
 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                 .procname       = "prove_locking",
 371                 .data           = &prove_locking,
 372                 .maxlen         = sizeof(int),
 373                 .mode           = 0644,
 374                 .proc_handler   = proc_dointvec,
 375         },
 376 #endif
 377 #ifdef CONFIG_LOCK_STAT
 378         {
 379                 .procname       = "lock_stat",
 380                 .data           = &lock_stat,
 381                 .maxlen         = sizeof(int),
 382                 .mode           = 0644,
 383                 .proc_handler   = proc_dointvec,
 384         },
 385 #endif
 386         {
 387                 .procname       = "panic",
 388                 .data           = &panic_timeout,
 389                 .maxlen         = sizeof(int),
 390                 .mode           = 0644,
 391                 .proc_handler   = proc_dointvec,
 392         },
 393         {
 394                 .procname       = "core_uses_pid",
 395                 .data           = &core_uses_pid,
 396                 .maxlen         = sizeof(int),
 397                 .mode           = 0644,
 398                 .proc_handler   = proc_dointvec,
 399         },
 400         {
 401                 .procname       = "core_pattern",
 402                 .data           = core_pattern,
 403                 .maxlen         = CORENAME_MAX_SIZE,
 404                 .mode           = 0644,
 405                 .proc_handler   = proc_dostring,
 406         },
 407         {
 408                 .procname       = "core_pipe_limit",
 409                 .data           = &core_pipe_limit,
 410                 .maxlen         = sizeof(unsigned int),
 411                 .mode           = 0644,
 412                 .proc_handler   = proc_dointvec,
 413         },
 414 #ifdef CONFIG_PROC_SYSCTL
 415         {
 416                 .procname       = "tainted",
 417                 .maxlen         = sizeof(long),
 418                 .mode           = 0644,
 419                 .proc_handler   = proc_taint,
 420         },
 421 #endif
 422 #ifdef CONFIG_LATENCYTOP
 423         {
 424                 .procname       = "latencytop",
 425                 .data           = &latencytop_enabled,
 426                 .maxlen         = sizeof(int),
 427                 .mode           = 0644,
 428                 .proc_handler   = proc_dointvec,
 429         },
 430 #endif
 431 #ifdef CONFIG_BLK_DEV_INITRD
 432         {
 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                 .procname       = "print-fatal-signals",
 442                 .data           = &print_fatal_signals,
 443                 .maxlen         = sizeof(int),
 444                 .mode           = 0644,
 445                 .proc_handler   = proc_dointvec,
 446         },
 447 #ifdef CONFIG_SPARC
 448         {
 449                 .procname       = "reboot-cmd",
 450                 .data           = reboot_command,
 451                 .maxlen         = 256,
 452                 .mode           = 0644,
 453                 .proc_handler   = proc_dostring,
 454         },
 455         {
 456                 .procname       = "stop-a",
 457                 .data           = &stop_a_enabled,
 458                 .maxlen         = sizeof (int),
 459                 .mode           = 0644,
 460                 .proc_handler   = proc_dointvec,
 461         },
 462         {
 463                 .procname       = "scons-poweroff",
 464                 .data           = &scons_pwroff,
 465                 .maxlen         = sizeof (int),
 466                 .mode           = 0644,
 467                 .proc_handler   = proc_dointvec,
 468         },
 469 #endif
 470 #ifdef CONFIG_SPARC64
 471         {
 472                 .procname       = "tsb-ratio",
 473                 .data           = &sysctl_tsb_ratio,
 474                 .maxlen         = sizeof (int),
 475                 .mode           = 0644,
 476                 .proc_handler   = proc_dointvec,
 477         },
 478 #endif
 479 #ifdef __hppa__
 480         {
 481                 .procname       = "soft-power",
 482                 .data           = &pwrsw_enabled,
 483                 .maxlen         = sizeof (int),
 484                 .mode           = 0644,
 485                 .proc_handler   = proc_dointvec,
 486         },
 487         {
 488                 .procname       = "unaligned-trap",
 489                 .data           = &unaligned_enabled,
 490                 .maxlen         = sizeof (int),
 491                 .mode           = 0644,
 492                 .proc_handler   = proc_dointvec,
 493         },
 494 #endif
 495         {
 496                 .procname       = "ctrl-alt-del",
 497                 .data           = &C_A_D,
 498                 .maxlen         = sizeof(int),
 499                 .mode           = 0644,
 500                 .proc_handler   = proc_dointvec,
 501         },
 502 #ifdef CONFIG_FUNCTION_TRACER
 503         {
 504                 .procname       = "ftrace_enabled",
 505                 .data           = &ftrace_enabled,
 506                 .maxlen         = sizeof(int),
 507                 .mode           = 0644,
 508                 .proc_handler   = ftrace_enable_sysctl,
 509         },
 510 #endif
 511 #ifdef CONFIG_STACK_TRACER
 512         {
 513                 .procname       = "stack_tracer_enabled",
 514                 .data           = &stack_tracer_enabled,
 515                 .maxlen         = sizeof(int),
 516                 .mode           = 0644,
 517                 .proc_handler   = stack_trace_sysctl,
 518         },
 519 #endif
 520 #ifdef CONFIG_TRACING
 521         {
 522                 .procname       = "ftrace_dump_on_oops",
 523                 .data           = &ftrace_dump_on_oops,
 524                 .maxlen         = sizeof(int),
 525                 .mode           = 0644,
 526                 .proc_handler   = proc_dointvec,
 527         },
 528 #endif
 529 #ifdef CONFIG_MODULES
 530         {
 531                 .procname       = "modprobe",
 532                 .data           = &modprobe_path,
 533                 .maxlen         = KMOD_PATH_LEN,
 534                 .mode           = 0644,
 535                 .proc_handler   = proc_dostring,
 536         },
 537         {
 538                 .procname       = "modules_disabled",
 539                 .data           = &modules_disabled,
 540                 .maxlen         = sizeof(int),
 541                 .mode           = 0644,
 542                 /* only handle a transition from default "0" to "1" */
 543                 .proc_handler   = proc_dointvec_minmax,
 544                 .extra1         = &one,
 545                 .extra2         = &one,
 546         },
 547 #endif
 548 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 549         {
 550                 .procname       = "hotplug",
 551                 .data           = &uevent_helper,
 552                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 553                 .mode           = 0644,
 554                 .proc_handler   = proc_dostring,
 555         },
 556 #endif
 557 #ifdef CONFIG_CHR_DEV_SG
 558         {
 559                 .procname       = "sg-big-buff",
 560                 .data           = &sg_big_buff,
 561                 .maxlen         = sizeof (int),
 562                 .mode           = 0444,
 563                 .proc_handler   = proc_dointvec,
 564         },
 565 #endif
 566 #ifdef CONFIG_BSD_PROCESS_ACCT
 567         {
 568                 .procname       = "acct",
 569                 .data           = &acct_parm,
 570                 .maxlen         = 3*sizeof(int),
 571                 .mode           = 0644,
 572                 .proc_handler   = proc_dointvec,
 573         },
 574 #endif
 575 #ifdef CONFIG_MAGIC_SYSRQ
 576         {
 577                 .procname       = "sysrq",
 578                 .data           = &__sysrq_enabled,
 579                 .maxlen         = sizeof (int),
 580                 .mode           = 0644,
 581                 .proc_handler   = proc_dointvec,
 582         },
 583 #endif
 584 #ifdef CONFIG_PROC_SYSCTL
 585         {
 586                 .procname       = "cad_pid",
 587                 .data           = NULL,
 588                 .maxlen         = sizeof (int),
 589                 .mode           = 0600,
 590                 .proc_handler   = proc_do_cad_pid,
 591         },
 592 #endif
 593         {
 594                 .procname       = "threads-max",
 595                 .data           = &max_threads,
 596                 .maxlen         = sizeof(int),
 597                 .mode           = 0644,
 598                 .proc_handler   = proc_dointvec,
 599         },
 600         {
 601                 .procname       = "random",
 602                 .mode           = 0555,
 603                 .child          = random_table,
 604         },
 605         {
 606                 .procname       = "overflowuid",
 607                 .data           = &overflowuid,
 608                 .maxlen         = sizeof(int),
 609                 .mode           = 0644,
 610                 .proc_handler   = proc_dointvec_minmax,
 611                 .extra1         = &minolduid,
 612                 .extra2         = &maxolduid,
 613         },
 614         {
 615                 .procname       = "overflowgid",
 616                 .data           = &overflowgid,
 617                 .maxlen         = sizeof(int),
 618                 .mode           = 0644,
 619                 .proc_handler   = proc_dointvec_minmax,
 620                 .extra1         = &minolduid,
 621                 .extra2         = &maxolduid,
 622         },
 623 #ifdef CONFIG_S390
 624 #ifdef CONFIG_MATHEMU
 625         {
 626                 .procname       = "ieee_emulation_warnings",
 627                 .data           = &sysctl_ieee_emulation_warnings,
 628                 .maxlen         = sizeof(int),
 629                 .mode           = 0644,
 630                 .proc_handler   = proc_dointvec,
 631         },
 632 #endif
 633         {
 634                 .procname       = "userprocess_debug",
 635                 .data           = &sysctl_userprocess_debug,
 636                 .maxlen         = sizeof(int),
 637                 .mode           = 0644,
 638                 .proc_handler   = proc_dointvec,
 639         },
 640 #endif
 641         {
 642                 .procname       = "pid_max",
 643                 .data           = &pid_max,
 644                 .maxlen         = sizeof (int),
 645                 .mode           = 0644,
 646                 .proc_handler   = proc_dointvec_minmax,
 647                 .extra1         = &pid_max_min,
 648                 .extra2         = &pid_max_max,
 649         },
 650         {
 651                 .procname       = "panic_on_oops",
 652                 .data           = &panic_on_oops,
 653                 .maxlen         = sizeof(int),
 654                 .mode           = 0644,
 655                 .proc_handler   = proc_dointvec,
 656         },
 657 #if defined CONFIG_PRINTK
 658         {
 659                 .procname       = "printk",
 660                 .data           = &console_loglevel,
 661                 .maxlen         = 4*sizeof(int),
 662                 .mode           = 0644,
 663                 .proc_handler   = proc_dointvec,
 664         },
 665         {
 666                 .procname       = "printk_ratelimit",
 667                 .data           = &printk_ratelimit_state.interval,
 668                 .maxlen         = sizeof(int),
 669                 .mode           = 0644,
 670                 .proc_handler   = proc_dointvec_jiffies,
 671         },
 672         {
 673                 .procname       = "printk_ratelimit_burst",
 674                 .data           = &printk_ratelimit_state.burst,
 675                 .maxlen         = sizeof(int),
 676                 .mode           = 0644,
 677                 .proc_handler   = proc_dointvec,
 678         },
 679         {
 680                 .procname       = "printk_delay",
 681                 .data           = &printk_delay_msec,
 682                 .maxlen         = sizeof(int),
 683                 .mode           = 0644,
 684                 .proc_handler   = proc_dointvec_minmax,
 685                 .extra1         = &zero,
 686                 .extra2         = &ten_thousand,
 687         },
 688 #endif
 689         {
 690                 .procname       = "ngroups_max",
 691                 .data           = &ngroups_max,
 692                 .maxlen         = sizeof (int),
 693                 .mode           = 0444,
 694                 .proc_handler   = proc_dointvec,
 695         },
 696 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 697         {
 698                 .procname       = "unknown_nmi_panic",
 699                 .data           = &unknown_nmi_panic,
 700                 .maxlen         = sizeof (int),
 701                 .mode           = 0644,
 702                 .proc_handler   = proc_dointvec,
 703         },
 704         {
 705                 .procname       = "nmi_watchdog",
 706                 .data           = &nmi_watchdog_enabled,
 707                 .maxlen         = sizeof (int),
 708                 .mode           = 0644,
 709                 .proc_handler   = proc_nmi_enabled,
 710         },
 711 #endif
 712 #if defined(CONFIG_X86)
 713         {
 714                 .procname       = "panic_on_unrecovered_nmi",
 715                 .data           = &panic_on_unrecovered_nmi,
 716                 .maxlen         = sizeof(int),
 717                 .mode           = 0644,
 718                 .proc_handler   = proc_dointvec,
 719         },
 720         {
 721                 .procname       = "panic_on_io_nmi",
 722                 .data           = &panic_on_io_nmi,
 723                 .maxlen         = sizeof(int),
 724                 .mode           = 0644,
 725                 .proc_handler   = proc_dointvec,
 726         },
 727         {
 728                 .procname       = "bootloader_type",
 729                 .data           = &bootloader_type,
 730                 .maxlen         = sizeof (int),
 731                 .mode           = 0444,
 732                 .proc_handler   = proc_dointvec,
 733         },
 734         {
 735                 .procname       = "bootloader_version",
 736                 .data           = &bootloader_version,
 737                 .maxlen         = sizeof (int),
 738                 .mode           = 0444,
 739                 .proc_handler   = proc_dointvec,
 740         },
 741         {
 742                 .procname       = "kstack_depth_to_print",
 743                 .data           = &kstack_depth_to_print,
 744                 .maxlen         = sizeof(int),
 745                 .mode           = 0644,
 746                 .proc_handler   = proc_dointvec,
 747         },
 748         {
 749                 .procname       = "io_delay_type",
 750                 .data           = &io_delay_type,
 751                 .maxlen         = sizeof(int),
 752                 .mode           = 0644,
 753                 .proc_handler   = proc_dointvec,
 754         },
 755 #endif
 756 #if defined(CONFIG_MMU)
 757         {
 758                 .procname       = "randomize_va_space",
 759                 .data           = &randomize_va_space,
 760                 .maxlen         = sizeof(int),
 761                 .mode           = 0644,
 762                 .proc_handler   = proc_dointvec,
 763         },
 764 #endif
 765 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 766         {
 767                 .procname       = "spin_retry",
 768                 .data           = &spin_retry,
 769                 .maxlen         = sizeof (int),
 770                 .mode           = 0644,
 771                 .proc_handler   = proc_dointvec,
 772         },
 773 #endif
 774 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 775         {
 776                 .procname       = "acpi_video_flags",
 777                 .data           = &acpi_realmode_flags,
 778                 .maxlen         = sizeof (unsigned long),
 779                 .mode           = 0644,
 780                 .proc_handler   = proc_doulongvec_minmax,
 781         },
 782 #endif
 783 #ifdef CONFIG_IA64
 784         {
 785                 .procname       = "ignore-unaligned-usertrap",
 786                 .data           = &no_unaligned_warning,
 787                 .maxlen         = sizeof (int),
 788                 .mode           = 0644,
 789                 .proc_handler   = proc_dointvec,
 790         },
 791         {
 792                 .procname       = "unaligned-dump-stack",
 793                 .data           = &unaligned_dump_stack,
 794                 .maxlen         = sizeof (int),
 795                 .mode           = 0644,
 796                 .proc_handler   = proc_dointvec,
 797         },
 798 #endif
 799 #ifdef CONFIG_DETECT_SOFTLOCKUP
 800         {
 801                 .procname       = "softlockup_panic",
 802                 .data           = &softlockup_panic,
 803                 .maxlen         = sizeof(int),
 804                 .mode           = 0644,
 805                 .proc_handler   = proc_dointvec_minmax,
 806                 .extra1         = &zero,
 807                 .extra2         = &one,
 808         },
 809         {
 810                 .procname       = "softlockup_thresh",
 811                 .data           = &softlockup_thresh,
 812                 .maxlen         = sizeof(int),
 813                 .mode           = 0644,
 814                 .proc_handler   = proc_dosoftlockup_thresh,
 815                 .extra1         = &neg_one,
 816                 .extra2         = &sixty,
 817         },
 818 #endif
 819 #ifdef CONFIG_DETECT_HUNG_TASK
 820         {
 821                 .procname       = "hung_task_panic",
 822                 .data           = &sysctl_hung_task_panic,
 823                 .maxlen         = sizeof(int),
 824                 .mode           = 0644,
 825                 .proc_handler   = proc_dointvec_minmax,
 826                 .extra1         = &zero,
 827                 .extra2         = &one,
 828         },
 829         {
 830                 .procname       = "hung_task_check_count",
 831                 .data           = &sysctl_hung_task_check_count,
 832                 .maxlen         = sizeof(unsigned long),
 833                 .mode           = 0644,
 834                 .proc_handler   = proc_doulongvec_minmax,
 835         },
 836         {
 837                 .procname       = "hung_task_timeout_secs",
 838                 .data           = &sysctl_hung_task_timeout_secs,
 839                 .maxlen         = sizeof(unsigned long),
 840                 .mode           = 0644,
 841                 .proc_handler   = proc_dohung_task_timeout_secs,
 842         },
 843         {
 844                 .procname       = "hung_task_warnings",
 845                 .data           = &sysctl_hung_task_warnings,
 846                 .maxlen         = sizeof(unsigned long),
 847                 .mode           = 0644,
 848                 .proc_handler   = proc_doulongvec_minmax,
 849         },
 850 #endif
 851 #ifdef CONFIG_COMPAT
 852         {
 853                 .procname       = "compat-log",
 854                 .data           = &compat_log,
 855                 .maxlen         = sizeof (int),
 856                 .mode           = 0644,
 857                 .proc_handler   = proc_dointvec,
 858         },
 859 #endif
 860 #ifdef CONFIG_RT_MUTEXES
 861         {
 862                 .procname       = "max_lock_depth",
 863                 .data           = &max_lock_depth,
 864                 .maxlen         = sizeof(int),
 865                 .mode           = 0644,
 866                 .proc_handler   = proc_dointvec,
 867         },
 868 #endif
 869         {
 870                 .procname       = "poweroff_cmd",
 871                 .data           = &poweroff_cmd,
 872                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 873                 .mode           = 0644,
 874                 .proc_handler   = proc_dostring,
 875         },
 876 #ifdef CONFIG_KEYS
 877         {
 878                 .procname       = "keys",
 879                 .mode           = 0555,
 880                 .child          = key_sysctls,
 881         },
 882 #endif
 883 #ifdef CONFIG_RCU_TORTURE_TEST
 884         {
 885                 .procname       = "rcutorture_runnable",
 886                 .data           = &rcutorture_runnable,
 887                 .maxlen         = sizeof(int),
 888                 .mode           = 0644,
 889                 .proc_handler   = proc_dointvec,
 890         },
 891 #endif
 892 #ifdef CONFIG_SLOW_WORK
 893         {
 894                 .procname       = "slow-work",
 895                 .mode           = 0555,
 896                 .child          = slow_work_sysctls,
 897         },
 898 #endif
 899 #ifdef CONFIG_PERF_EVENTS
 900         {
 901                 .procname       = "perf_event_paranoid",
 902                 .data           = &sysctl_perf_event_paranoid,
 903                 .maxlen         = sizeof(sysctl_perf_event_paranoid),
 904                 .mode           = 0644,
 905                 .proc_handler   = proc_dointvec,
 906         },
 907         {
 908                 .procname       = "perf_event_mlock_kb",
 909                 .data           = &sysctl_perf_event_mlock,
 910                 .maxlen         = sizeof(sysctl_perf_event_mlock),
 911                 .mode           = 0644,
 912                 .proc_handler   = proc_dointvec,
 913         },
 914         {
 915                 .procname       = "perf_event_max_sample_rate",
 916                 .data           = &sysctl_perf_event_sample_rate,
 917                 .maxlen         = sizeof(sysctl_perf_event_sample_rate),
 918                 .mode           = 0644,
 919                 .proc_handler   = proc_dointvec,
 920         },
 921 #endif
 922 #ifdef CONFIG_KMEMCHECK
 923         {
 924                 .procname       = "kmemcheck",
 925                 .data           = &kmemcheck_enabled,
 926                 .maxlen         = sizeof(int),
 927                 .mode           = 0644,
 928                 .proc_handler   = proc_dointvec,
 929         },
 930 #endif
 931 #ifdef CONFIG_BLOCK
 932         {
 933                 .procname       = "blk_iopoll",
 934                 .data           = &blk_iopoll_enabled,
 935                 .maxlen         = sizeof(int),
 936                 .mode           = 0644,
 937                 .proc_handler   = proc_dointvec,
 938         },
 939 #endif
 940 /*
 941  * NOTE: do not add new entries to this table unless you have read
 942  * Documentation/sysctl/ctl_unnumbered.txt
 943  */
 944         { }
 945 };
 946
 947 static struct ctl_table vm_table[] = {
 948         {
 949                 .procname       = "overcommit_memory",
 950                 .data           = &sysctl_overcommit_memory,
 951                 .maxlen         = sizeof(sysctl_overcommit_memory),
 952                 .mode           = 0644,
 953                 .proc_handler   = proc_dointvec,
 954         },
 955         {
 956                 .procname       = "panic_on_oom",
 957                 .data           = &sysctl_panic_on_oom,
 958                 .maxlen         = sizeof(sysctl_panic_on_oom),
 959                 .mode           = 0644,
 960                 .proc_handler   = proc_dointvec,
 961         },
 962         {
 963                 .procname       = "oom_kill_allocating_task",
 964                 .data           = &sysctl_oom_kill_allocating_task,
 965                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
 966                 .mode           = 0644,
 967                 .proc_handler   = proc_dointvec,
 968         },
 969         {
 970                 .procname       = "oom_dump_tasks",
 971                 .data           = &sysctl_oom_dump_tasks,
 972                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
 973                 .mode           = 0644,
 974                 .proc_handler   = proc_dointvec,
 975         },
 976         {
 977                 .procname       = "overcommit_ratio",
 978                 .data           = &sysctl_overcommit_ratio,
 979                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 980                 .mode           = 0644,
 981                 .proc_handler   = proc_dointvec,
 982         },
 983         {
 984                 .procname       = "page-cluster",
 985                 .data           = &page_cluster,
 986                 .maxlen         = sizeof(int),
 987                 .mode           = 0644,
 988                 .proc_handler   = proc_dointvec,
 989         },
 990         {
 991                 .procname       = "dirty_background_ratio",
 992                 .data           = &dirty_background_ratio,
 993                 .maxlen         = sizeof(dirty_background_ratio),
 994                 .mode           = 0644,
 995                 .proc_handler   = dirty_background_ratio_handler,
 996                 .extra1         = &zero,
 997                 .extra2         = &one_hundred,
 998         },
 999         {
1000                 .procname       = "dirty_background_bytes",
1001                 .data           = &dirty_background_bytes,
1002                 .maxlen         = sizeof(dirty_background_bytes),
1003                 .mode           = 0644,
1004                 .proc_handler   = dirty_background_bytes_handler,
1005                 .extra1         = &one_ul,
1006         },
1007         {
1008                 .procname       = "dirty_ratio",
1009                 .data           = &vm_dirty_ratio,
1010                 .maxlen         = sizeof(vm_dirty_ratio),
1011                 .mode           = 0644,
1012                 .proc_handler   = dirty_ratio_handler,
1013                 .extra1         = &zero,
1014                 .extra2         = &one_hundred,
1015         },
1016         {
1017                 .procname       = "dirty_bytes",
1018                 .data           = &vm_dirty_bytes,
1019                 .maxlen         = sizeof(vm_dirty_bytes),
1020                 .mode           = 0644,
1021                 .proc_handler   = dirty_bytes_handler,
1022                 .extra1         = &dirty_bytes_min,
1023         },
1024         {
1025                 .procname       = "dirty_writeback_centisecs",
1026                 .data           = &dirty_writeback_interval,
1027                 .maxlen         = sizeof(dirty_writeback_interval),
1028                 .mode           = 0644,
1029                 .proc_handler   = dirty_writeback_centisecs_handler,
1030         },
1031         {
1032                 .procname       = "dirty_expire_centisecs",
1033                 .data           = &dirty_expire_interval,
1034                 .maxlen         = sizeof(dirty_expire_interval),
1035                 .mode           = 0644,
1036                 .proc_handler   = proc_dointvec,
1037         },
1038         {
1039                 .procname       = "nr_pdflush_threads",
1040                 .data           = &nr_pdflush_threads,
1041                 .maxlen         = sizeof nr_pdflush_threads,
1042                 .mode           = 0444 /* read-only*/,
1043                 .proc_handler   = proc_dointvec,
1044         },
1045         {
1046                 .procname       = "swappiness",
1047                 .data           = &vm_swappiness,
1048                 .maxlen         = sizeof(vm_swappiness),
1049                 .mode           = 0644,
1050                 .proc_handler   = proc_dointvec_minmax,
1051                 .extra1         = &zero,
1052                 .extra2         = &one_hundred,
1053         },
1054 #ifdef CONFIG_HUGETLB_PAGE
1055         {
1056                 .procname       = "nr_hugepages",
1057                 .data           = NULL,
1058                 .maxlen         = sizeof(unsigned long),
1059                 .mode           = 0644,
1060                 .proc_handler   = hugetlb_sysctl_handler,
1061                 .extra1         = (void *)&hugetlb_zero,
1062                 .extra2         = (void *)&hugetlb_infinity,
1063         },
1064 #ifdef CONFIG_NUMA
1065         {
1066                 .procname       = "nr_hugepages_mempolicy",
1067                 .data           = NULL,
1068                 .maxlen         = sizeof(unsigned long),
1069                 .mode           = 0644,
1070                 .proc_handler   = &hugetlb_mempolicy_sysctl_handler,
1071                 .extra1         = (void *)&hugetlb_zero,
1072                 .extra2         = (void *)&hugetlb_infinity,
1073         },
1074 #endif
1075          {
1076                 .procname       = "hugetlb_shm_group",
1077                 .data           = &sysctl_hugetlb_shm_group,
1078                 .maxlen         = sizeof(gid_t),
1079                 .mode           = 0644,
1080                 .proc_handler   = proc_dointvec,
1081          },
1082          {
1083                 .procname       = "hugepages_treat_as_movable",
1084                 .data           = &hugepages_treat_as_movable,
1085                 .maxlen         = sizeof(int),
1086                 .mode           = 0644,
1087                 .proc_handler   = hugetlb_treat_movable_handler,
1088         },
1089         {
1090                 .procname       = "nr_overcommit_hugepages",
1091                 .data           = NULL,
1092                 .maxlen         = sizeof(unsigned long),
1093                 .mode           = 0644,
1094                 .proc_handler   = hugetlb_overcommit_handler,
1095                 .extra1         = (void *)&hugetlb_zero,
1096                 .extra2         = (void *)&hugetlb_infinity,
1097         },
1098 #endif
1099         {
1100                 .procname       = "lowmem_reserve_ratio",
1101                 .data           = &sysctl_lowmem_reserve_ratio,
1102                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1103                 .mode           = 0644,
1104                 .proc_handler   = lowmem_reserve_ratio_sysctl_handler,
1105         },
1106         {
1107                 .procname       = "drop_caches",
1108                 .data           = &sysctl_drop_caches,
1109                 .maxlen         = sizeof(int),
1110                 .mode           = 0644,
1111                 .proc_handler   = drop_caches_sysctl_handler,
1112         },
1113         {
1114                 .procname       = "min_free_kbytes",
1115                 .data           = &min_free_kbytes,
1116                 .maxlen         = sizeof(min_free_kbytes),
1117                 .mode           = 0644,
1118                 .proc_handler   = min_free_kbytes_sysctl_handler,
1119                 .extra1         = &zero,
1120         },
1121         {
1122                 .procname       = "percpu_pagelist_fraction",
1123                 .data           = &percpu_pagelist_fraction,
1124                 .maxlen         = sizeof(percpu_pagelist_fraction),
1125                 .mode           = 0644,
1126                 .proc_handler   = percpu_pagelist_fraction_sysctl_handler,
1127                 .extra1         = &min_percpu_pagelist_fract,
1128         },
1129 #ifdef CONFIG_MMU
1130         {
1131                 .procname       = "max_map_count",
1132                 .data           = &sysctl_max_map_count,
1133                 .maxlen         = sizeof(sysctl_max_map_count),
1134                 .mode           = 0644,
1135                 .proc_handler   = proc_dointvec_minmax,
1136                 .extra1         = &zero,
1137         },
1138 #else
1139         {
1140                 .procname       = "nr_trim_pages",
1141                 .data           = &sysctl_nr_trim_pages,
1142                 .maxlen         = sizeof(sysctl_nr_trim_pages),
1143                 .mode           = 0644,
1144                 .proc_handler   = proc_dointvec_minmax,
1145                 .extra1         = &zero,
1146         },
1147 #endif
1148         {
1149                 .procname       = "laptop_mode",
1150                 .data           = &laptop_mode,
1151                 .maxlen         = sizeof(laptop_mode),
1152                 .mode           = 0644,
1153                 .proc_handler   = proc_dointvec_jiffies,
1154         },
1155         {
1156                 .procname       = "block_dump",
1157                 .data           = &block_dump,
1158                 .maxlen         = sizeof(block_dump),
1159                 .mode           = 0644,
1160                 .proc_handler   = proc_dointvec,
1161                 .extra1         = &zero,
1162         },
1163         {
1164                 .procname       = "vfs_cache_pressure",
1165                 .data           = &sysctl_vfs_cache_pressure,
1166                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1167                 .mode           = 0644,
1168                 .proc_handler   = proc_dointvec,
1169                 .extra1         = &zero,
1170         },
1171 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1172         {
1173                 .procname       = "legacy_va_layout",
1174                 .data           = &sysctl_legacy_va_layout,
1175                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1176                 .mode           = 0644,
1177                 .proc_handler   = proc_dointvec,
1178                 .extra1         = &zero,
1179         },
1180 #endif
1181 #ifdef CONFIG_NUMA
1182         {
1183                 .procname       = "zone_reclaim_mode",
1184                 .data           = &zone_reclaim_mode,
1185                 .maxlen         = sizeof(zone_reclaim_mode),
1186                 .mode           = 0644,
1187                 .proc_handler   = proc_dointvec,
1188                 .extra1         = &zero,
1189         },
1190         {
1191                 .procname       = "min_unmapped_ratio",
1192                 .data           = &sysctl_min_unmapped_ratio,
1193                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1194                 .mode           = 0644,
1195                 .proc_handler   = sysctl_min_unmapped_ratio_sysctl_handler,
1196                 .extra1         = &zero,
1197                 .extra2         = &one_hundred,
1198         },
1199         {
1200                 .procname       = "min_slab_ratio",
1201                 .data           = &sysctl_min_slab_ratio,
1202                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1203                 .mode           = 0644,
1204                 .proc_handler   = sysctl_min_slab_ratio_sysctl_handler,
1205                 .extra1         = &zero,
1206                 .extra2         = &one_hundred,
1207         },
1208 #endif
1209 #ifdef CONFIG_SMP
1210         {
1211                 .procname       = "stat_interval",
1212                 .data           = &sysctl_stat_interval,
1213                 .maxlen         = sizeof(sysctl_stat_interval),
1214                 .mode           = 0644,
1215                 .proc_handler   = proc_dointvec_jiffies,
1216         },
1217 #endif
1218 #ifdef CONFIG_MMU
1219         {
1220                 .procname       = "mmap_min_addr",
1221                 .data           = &dac_mmap_min_addr,
1222                 .maxlen         = sizeof(unsigned long),
1223                 .mode           = 0644,
1224                 .proc_handler   = mmap_min_addr_handler,
1225         },
1226 #endif
1227 #ifdef CONFIG_NUMA
1228         {
1229                 .procname       = "numa_zonelist_order",
1230                 .data           = &numa_zonelist_order,
1231                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1232                 .mode           = 0644,
1233                 .proc_handler   = numa_zonelist_order_handler,
1234         },
1235 #endif
1236 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1237    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1238         {
1239                 .procname       = "vdso_enabled",
1240                 .data           = &vdso_enabled,
1241                 .maxlen         = sizeof(vdso_enabled),
1242                 .mode           = 0644,
1243                 .proc_handler   = proc_dointvec,
1244                 .extra1         = &zero,
1245         },
1246 #endif
1247 #ifdef CONFIG_HIGHMEM
1248         {
1249                 .procname       = "highmem_is_dirtyable",
1250                 .data           = &vm_highmem_is_dirtyable,
1251                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1252                 .mode           = 0644,
1253                 .proc_handler   = proc_dointvec_minmax,
1254                 .extra1         = &zero,
1255                 .extra2         = &one,
1256         },
1257 #endif
1258         {
1259                 .procname       = "scan_unevictable_pages",
1260                 .data           = &scan_unevictable_pages,
1261                 .maxlen         = sizeof(scan_unevictable_pages),
1262                 .mode           = 0644,
1263                 .proc_handler   = scan_unevictable_handler,
1264         },
1265 #ifdef CONFIG_MEMORY_FAILURE
1266         {
1267                 .procname       = "memory_failure_early_kill",
1268                 .data           = &sysctl_memory_failure_early_kill,
1269                 .maxlen         = sizeof(sysctl_memory_failure_early_kill),
1270                 .mode           = 0644,
1271                 .proc_handler   = proc_dointvec_minmax,
1272                 .extra1         = &zero,
1273                 .extra2         = &one,
1274         },
1275         {
1276                 .procname       = "memory_failure_recovery",
1277                 .data           = &sysctl_memory_failure_recovery,
1278                 .maxlen         = sizeof(sysctl_memory_failure_recovery),
1279                 .mode           = 0644,
1280                 .proc_handler   = proc_dointvec_minmax,
1281                 .extra1         = &zero,
1282                 .extra2         = &one,
1283         },
1284 #endif
1285
1286 /*
1287  * NOTE: do not add new entries to this table unless you have read
1288  * Documentation/sysctl/ctl_unnumbered.txt
1289  */
1290         { }
1291 };
1292
1293 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1294 static struct ctl_table binfmt_misc_table[] = {
1295         { }
1296 };
1297 #endif
1298
1299 static struct ctl_table fs_table[] = {
1300         {
1301                 .procname       = "inode-nr",
1302                 .data           = &inodes_stat,
1303                 .maxlen         = 2*sizeof(int),
1304                 .mode           = 0444,
1305                 .proc_handler   = proc_dointvec,
1306         },
1307         {
1308                 .procname       = "inode-state",
1309                 .data           = &inodes_stat,
1310                 .maxlen         = 7*sizeof(int),
1311                 .mode           = 0444,
1312                 .proc_handler   = proc_dointvec,
1313         },
1314         {
1315                 .procname       = "file-nr",
1316                 .data           = &files_stat,
1317                 .maxlen         = 3*sizeof(int),
1318                 .mode           = 0444,
1319                 .proc_handler   = proc_nr_files,
1320         },
1321         {
1322                 .procname       = "file-max",
1323                 .data           = &files_stat.max_files,
1324                 .maxlen         = sizeof(int),
1325                 .mode           = 0644,
1326                 .proc_handler   = proc_dointvec,
1327         },
1328         {
1329                 .procname       = "nr_open",
1330                 .data           = &sysctl_nr_open,
1331                 .maxlen         = sizeof(int),
1332                 .mode           = 0644,
1333                 .proc_handler   = proc_dointvec_minmax,
1334                 .extra1         = &sysctl_nr_open_min,
1335                 .extra2         = &sysctl_nr_open_max,
1336         },
1337         {
1338                 .procname       = "dentry-state",
1339                 .data           = &dentry_stat,
1340                 .maxlen         = 6*sizeof(int),
1341                 .mode           = 0444,
1342                 .proc_handler   = proc_dointvec,
1343         },
1344         {
1345                 .procname       = "overflowuid",
1346                 .data           = &fs_overflowuid,
1347                 .maxlen         = sizeof(int),
1348                 .mode           = 0644,
1349                 .proc_handler   = proc_dointvec_minmax,
1350                 .extra1         = &minolduid,
1351                 .extra2         = &maxolduid,
1352         },
1353         {
1354                 .procname       = "overflowgid",
1355                 .data           = &fs_overflowgid,
1356                 .maxlen         = sizeof(int),
1357                 .mode           = 0644,
1358                 .proc_handler   = proc_dointvec_minmax,
1359                 .extra1         = &minolduid,
1360                 .extra2         = &maxolduid,
1361         },
1362 #ifdef CONFIG_FILE_LOCKING
1363         {
1364                 .procname       = "leases-enable",
1365                 .data           = &leases_enable,
1366                 .maxlen         = sizeof(int),
1367                 .mode           = 0644,
1368                 .proc_handler   = proc_dointvec,
1369         },
1370 #endif
1371 #ifdef CONFIG_DNOTIFY
1372         {
1373                 .procname       = "dir-notify-enable",
1374                 .data           = &dir_notify_enable,
1375                 .maxlen         = sizeof(int),
1376                 .mode           = 0644,
1377                 .proc_handler   = proc_dointvec,
1378         },
1379 #endif
1380 #ifdef CONFIG_MMU
1381 #ifdef CONFIG_FILE_LOCKING
1382         {
1383                 .procname       = "lease-break-time",
1384                 .data           = &lease_break_time,
1385                 .maxlen         = sizeof(int),
1386                 .mode           = 0644,
1387                 .proc_handler   = proc_dointvec,
1388         },
1389 #endif
1390 #ifdef CONFIG_AIO
1391         {
1392                 .procname       = "aio-nr",
1393                 .data           = &aio_nr,
1394                 .maxlen         = sizeof(aio_nr),
1395                 .mode           = 0444,
1396                 .proc_handler   = proc_doulongvec_minmax,
1397         },
1398         {
1399                 .procname       = "aio-max-nr",
1400                 .data           = &aio_max_nr,
1401                 .maxlen         = sizeof(aio_max_nr),
1402                 .mode           = 0644,
1403                 .proc_handler   = proc_doulongvec_minmax,
1404         },
1405 #endif /* CONFIG_AIO */
1406 #ifdef CONFIG_INOTIFY_USER
1407         {
1408                 .procname       = "inotify",
1409                 .mode           = 0555,
1410                 .child          = inotify_table,
1411         },
1412 #endif
1413 #ifdef CONFIG_EPOLL
1414         {
1415                 .procname       = "epoll",
1416                 .mode           = 0555,
1417                 .child          = epoll_table,
1418         },
1419 #endif
1420 #endif
1421         {
1422                 .procname       = "suid_dumpable",
1423                 .data           = &suid_dumpable,
1424                 .maxlen         = sizeof(int),
1425                 .mode           = 0644,
1426                 .proc_handler   = proc_dointvec_minmax,
1427                 .extra1         = &zero,
1428                 .extra2         = &two,
1429         },
1430 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1431         {
1432                 .procname       = "binfmt_misc",
1433                 .mode           = 0555,
1434                 .child          = binfmt_misc_table,
1435         },
1436 #endif
1437 /*
1438  * NOTE: do not add new entries to this table unless you have read
1439  * Documentation/sysctl/ctl_unnumbered.txt
1440  */
1441         { }
1442 };
1443
1444 static struct ctl_table debug_table[] = {
1445 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC)
1446         {
1447                 .procname       = "exception-trace",
1448                 .data           = &show_unhandled_signals,
1449                 .maxlen         = sizeof(int),
1450                 .mode           = 0644,
1451                 .proc_handler   = proc_dointvec
1452         },
1453 #endif
1454 #if defined(CONFIG_OPTPROBES)
1455         {
1456                 .procname       = "kprobes-optimization",
1457                 .data           = &sysctl_kprobes_optimization,
1458                 .maxlen         = sizeof(int),
1459                 .mode           = 0644,
1460                 .proc_handler   = proc_kprobes_optimization_handler,
1461                 .extra1         = &zero,
1462                 .extra2         = &one,
1463         },
1464 #endif
1465         { }
1466 };
1467
1468 static struct ctl_table dev_table[] = {
1469         { }
1470 };
1471
1472 static DEFINE_SPINLOCK(sysctl_lock);
1473
1474 /* called under sysctl_lock */
1475 static int use_table(struct ctl_table_header *p)
1476 {
1477         if (unlikely(p->unregistering))
1478                 return 0;
1479         p->used++;
1480         return 1;
1481 }
1482
1483 /* called under sysctl_lock */
1484 static void unuse_table(struct ctl_table_header *p)
1485 {
1486         if (!--p->used)
1487                 if (unlikely(p->unregistering))
1488                         complete(p->unregistering);
1489 }
1490
1491 /* called under sysctl_lock, will reacquire if has to wait */
1492 static void start_unregistering(struct ctl_table_header *p)
1493 {
1494         /*
1495          * if p->used is 0, nobody will ever touch that entry again;
1496          * we'll eliminate all paths to it before dropping sysctl_lock
1497          */
1498         if (unlikely(p->used)) {
1499                 struct completion wait;
1500                 init_completion(&wait);
1501                 p->unregistering = &wait;
1502                 spin_unlock(&sysctl_lock);
1503                 wait_for_completion(&wait);
1504                 spin_lock(&sysctl_lock);
1505         } else {
1506                 /* anything non-NULL; we'll never dereference it */
1507                 p->unregistering = ERR_PTR(-EINVAL);
1508         }
1509         /*
1510          * do not remove from the list until nobody holds it; walking the
1511          * list in do_sysctl() relies on that.
1512          */
1513         list_del_init(&p->ctl_entry);
1514 }
1515
1516 void sysctl_head_get(struct ctl_table_header *head)
1517 {
1518         spin_lock(&sysctl_lock);
1519         head->count++;
1520         spin_unlock(&sysctl_lock);
1521 }
1522
1523 void sysctl_head_put(struct ctl_table_header *head)
1524 {
1525         spin_lock(&sysctl_lock);
1526         if (!--head->count)
1527                 kfree(head);
1528         spin_unlock(&sysctl_lock);
1529 }
1530
1531 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1532 {
1533         if (!head)
1534                 BUG();
1535         spin_lock(&sysctl_lock);
1536         if (!use_table(head))
1537                 head = ERR_PTR(-ENOENT);
1538         spin_unlock(&sysctl_lock);
1539         return head;
1540 }
1541
1542 void sysctl_head_finish(struct ctl_table_header *head)
1543 {
1544         if (!head)
1545                 return;
1546         spin_lock(&sysctl_lock);
1547         unuse_table(head);
1548         spin_unlock(&sysctl_lock);
1549 }
1550
1551 static struct ctl_table_set *
1552 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1553 {
1554         struct ctl_table_set *set = &root->default_set;
1555         if (root->lookup)
1556                 set = root->lookup(root, namespaces);
1557         return set;
1558 }
1559
1560 static struct list_head *
1561 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1562 {
1563         struct ctl_table_set *set = lookup_header_set(root, namespaces);
1564         return &set->list;
1565 }
1566
1567 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1568                                             struct ctl_table_header *prev)
1569 {
1570         struct ctl_table_root *root;
1571         struct list_head *header_list;
1572         struct ctl_table_header *head;
1573         struct list_head *tmp;
1574
1575         spin_lock(&sysctl_lock);
1576         if (prev) {
1577                 head = prev;
1578                 tmp = &prev->ctl_entry;
1579                 unuse_table(prev);
1580                 goto next;
1581         }
1582         tmp = &root_table_header.ctl_entry;
1583         for (;;) {
1584                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1585
1586                 if (!use_table(head))
1587                         goto next;
1588                 spin_unlock(&sysctl_lock);
1589                 return head;
1590         next:
1591                 root = head->root;
1592                 tmp = tmp->next;
1593                 header_list = lookup_header_list(root, namespaces);
1594                 if (tmp != header_list)
1595                         continue;
1596
1597                 do {
1598                         root = list_entry(root->root_list.next,
1599                                         struct ctl_table_root, root_list);
1600                         if (root == &sysctl_table_root)
1601                                 goto out;
1602                         header_list = lookup_header_list(root, namespaces);
1603                 } while (list_empty(header_list));
1604                 tmp = header_list->next;
1605         }
1606 out:
1607         spin_unlock(&sysctl_lock);
1608         return NULL;
1609 }
1610
1611 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1612 {
1613         return __sysctl_head_next(current->nsproxy, prev);
1614 }
1615
1616 void register_sysctl_root(struct ctl_table_root *root)
1617 {
1618         spin_lock(&sysctl_lock);
1619         list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1620         spin_unlock(&sysctl_lock);
1621 }
1622
1623 /*
1624  * sysctl_perm does NOT grant the superuser all rights automatically, because
1625  * some sysctl variables are readonly even to root.
1626  */
1627
1628 static int test_perm(int mode, int op)
1629 {
1630         if (!current_euid())
1631                 mode >>= 6;
1632         else if (in_egroup_p(0))
1633                 mode >>= 3;
1634         if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1635                 return 0;
1636         return -EACCES;
1637 }
1638
1639 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1640 {
1641         int error;
1642         int mode;
1643
1644         error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1645         if (error)
1646                 return error;
1647
1648         if (root->permissions)
1649                 mode = root->permissions(root, current->nsproxy, table);
1650         else
1651                 mode = table->mode;
1652
1653         return test_perm(mode, op);
1654 }
1655
1656 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1657 {
1658         for (; table->procname; table++) {
1659                 table->parent = parent;
1660                 if (table->child)
1661                         sysctl_set_parent(table, table->child);
1662         }
1663 }
1664
1665 static __init int sysctl_init(void)
1666 {
1667         sysctl_set_parent(NULL, root_table);
1668 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1669         {
1670                 int err;
1671                 err = sysctl_check_table(current->nsproxy, root_table);
1672         }
1673 #endif
1674         return 0;
1675 }
1676
1677 core_initcall(sysctl_init);
1678
1679 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1680                                       struct ctl_table *table)
1681 {
1682         struct ctl_table *p;
1683         const char *s = branch->procname;
1684
1685         /* branch should have named subdirectory as its first element */
1686         if (!s || !branch->child)
1687                 return NULL;
1688
1689         /* ... and nothing else */
1690         if (branch[1].procname)
1691                 return NULL;
1692
1693         /* table should contain subdirectory with the same name */
1694         for (p = table; p->procname; p++) {
1695                 if (!p->child)
1696                         continue;
1697                 if (p->procname && strcmp(p->procname, s) == 0)
1698                         return p;
1699         }
1700         return NULL;
1701 }
1702
1703 /* see if attaching q to p would be an improvement */
1704 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1705 {
1706         struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1707         struct ctl_table *next;
1708         int is_better = 0;
1709         int not_in_parent = !p->attached_by;
1710
1711         while ((next = is_branch_in(by, to)) != NULL) {
1712                 if (by == q->attached_by)
1713                         is_better = 1;
1714                 if (to == p->attached_by)
1715                         not_in_parent = 1;
1716                 by = by->child;
1717                 to = next->child;
1718         }
1719
1720         if (is_better && not_in_parent) {
1721                 q->attached_by = by;
1722                 q->attached_to = to;
1723                 q->parent = p;
1724         }
1725 }
1726
1727 /**
1728  * __register_sysctl_paths - register a sysctl hierarchy
1729  * @root: List of sysctl headers to register on
1730  * @namespaces: Data to compute which lists of sysctl entries are visible
1731  * @path: The path to the directory the sysctl table is in.
1732  * @table: the top-level table structure
1733  *
1734  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1735  * array. A completely 0 filled entry terminates the table.
1736  *
1737  * The members of the &struct ctl_table structure are used as follows:
1738  *
1739  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1740  *            enter a sysctl file
1741  *
1742  * data - a pointer to data for use by proc_handler
1743  *
1744  * maxlen - the maximum size in bytes of the data
1745  *
1746  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1747  *
1748  * child - a pointer to the child sysctl table if this entry is a directory, or
1749  *         %NULL.
1750  *
1751  * proc_handler - the text handler routine (described below)
1752  *
1753  * de - for internal use by the sysctl routines
1754  *
1755  * extra1, extra2 - extra pointers usable by the proc handler routines
1756  *
1757  * Leaf nodes in the sysctl tree will be represented by a single file
1758  * under /proc; non-leaf nodes will be represented by directories.
1759  *
1760  * sysctl(2) can automatically manage read and write requests through
1761  * the sysctl table.  The data and maxlen fields of the ctl_table
1762  * struct enable minimal validation of the values being written to be
1763  * performed, and the mode field allows minimal authentication.
1764  *
1765  * There must be a proc_handler routine for any terminal nodes
1766  * mirrored under /proc/sys (non-terminals are handled by a built-in
1767  * directory handler).  Several default handlers are available to
1768  * cover common cases -
1769  *
1770  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1771  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1772  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1773  *
1774  * It is the handler's job to read the input buffer from user memory
1775  * and process it. The handler should return 0 on success.
1776  *
1777  * This routine returns %NULL on a failure to register, and a pointer
1778  * to the table header on success.
1779  */
1780 struct ctl_table_header *__register_sysctl_paths(
1781         struct ctl_table_root *root,
1782         struct nsproxy *namespaces,
1783         const struct ctl_path *path, struct ctl_table *table)
1784 {
1785         struct ctl_table_header *header;
1786         struct ctl_table *new, **prevp;
1787         unsigned int n, npath;
1788         struct ctl_table_set *set;
1789
1790         /* Count the path components */
1791         for (npath = 0; path[npath].procname; ++npath)
1792                 ;
1793
1794         /*
1795          * For each path component, allocate a 2-element ctl_table array.
1796          * The first array element will be filled with the sysctl entry
1797          * for this, the second will be the sentinel (procname == 0).
1798          *
1799          * We allocate everything in one go so that we don't have to
1800          * worry about freeing additional memory in unregister_sysctl_table.
1801          */
1802         header = kzalloc(sizeof(struct ctl_table_header) +
1803                          (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1804         if (!header)
1805                 return NULL;
1806
1807         new = (struct ctl_table *) (header + 1);
1808
1809         /* Now connect the dots */
1810         prevp = &header->ctl_table;
1811         for (n = 0; n < npath; ++n, ++path) {
1812                 /* Copy the procname */
1813                 new->procname = path->procname;
1814                 new->mode     = 0555;
1815
1816                 *prevp = new;
1817                 prevp = &new->child;
1818
1819                 new += 2;
1820         }
1821         *prevp = table;
1822         header->ctl_table_arg = table;
1823
1824         INIT_LIST_HEAD(&header->ctl_entry);
1825         header->used = 0;
1826         header->unregistering = NULL;
1827         header->root = root;
1828         sysctl_set_parent(NULL, header->ctl_table);
1829         header->count = 1;
1830 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1831         if (sysctl_check_table(namespaces, header->ctl_table)) {
1832                 kfree(header);
1833                 return NULL;
1834         }
1835 #endif
1836         spin_lock(&sysctl_lock);
1837         header->set = lookup_header_set(root, namespaces);
1838         header->attached_by = header->ctl_table;
1839         header->attached_to = root_table;
1840         header->parent = &root_table_header;
1841         for (set = header->set; set; set = set->parent) {
1842                 struct ctl_table_header *p;
1843                 list_for_each_entry(p, &set->list, ctl_entry) {
1844                         if (p->unregistering)
1845                                 continue;
1846                         try_attach(p, header);
1847                 }
1848         }
1849         header->parent->count++;
1850         list_add_tail(&header->ctl_entry, &header->set->list);
1851         spin_unlock(&sysctl_lock);
1852
1853         return header;
1854 }
1855
1856 /**
1857  * register_sysctl_table_path - register a sysctl table hierarchy
1858  * @path: The path to the directory the sysctl table is in.
1859  * @table: the top-level table structure
1860  *
1861  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1862  * array. A completely 0 filled entry terminates the table.
1863  *
1864  * See __register_sysctl_paths for more details.
1865  */
1866 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1867                                                 struct ctl_table *table)
1868 {
1869         return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1870                                         path, table);
1871 }
1872
1873 /**
1874  * register_sysctl_table - register a sysctl table hierarchy
1875  * @table: the top-level table structure
1876  *
1877  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1878  * array. A completely 0 filled entry terminates the table.
1879  *
1880  * See register_sysctl_paths for more details.
1881  */
1882 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1883 {
1884         static const struct ctl_path null_path[] = { {} };
1885
1886         return register_sysctl_paths(null_path, table);
1887 }
1888
1889 /**
1890  * unregister_sysctl_table - unregister a sysctl table hierarchy
1891  * @header: the header returned from register_sysctl_table
1892  *
1893  * Unregisters the sysctl table and all children. proc entries may not
1894  * actually be removed until they are no longer used by anyone.
1895  */
1896 void unregister_sysctl_table(struct ctl_table_header * header)
1897 {
1898         might_sleep();
1899
1900         if (header == NULL)
1901                 return;
1902
1903         spin_lock(&sysctl_lock);
1904         start_unregistering(header);
1905         if (!--header->parent->count) {
1906                 WARN_ON(1);
1907                 kfree(header->parent);
1908         }
1909         if (!--header->count)
1910                 kfree(header);
1911         spin_unlock(&sysctl_lock);
1912 }
1913
1914 int sysctl_is_seen(struct ctl_table_header *p)
1915 {
1916         struct ctl_table_set *set = p->set;
1917         int res;
1918         spin_lock(&sysctl_lock);
1919         if (p->unregistering)
1920                 res = 0;
1921         else if (!set->is_seen)
1922                 res = 1;
1923         else
1924                 res = set->is_seen(set);
1925         spin_unlock(&sysctl_lock);
1926         return res;
1927 }
1928
1929 void setup_sysctl_set(struct ctl_table_set *p,
1930         struct ctl_table_set *parent,
1931         int (*is_seen)(struct ctl_table_set *))
1932 {
1933         INIT_LIST_HEAD(&p->list);
1934         p->parent = parent ? parent : &sysctl_table_root.default_set;
1935         p->is_seen = is_seen;
1936 }
1937
1938 #else /* !CONFIG_SYSCTL */
1939 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1940 {
1941         return NULL;
1942 }
1943
1944 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1945                                                     struct ctl_table *table)
1946 {
1947         return NULL;
1948 }
1949
1950 void unregister_sysctl_table(struct ctl_table_header * table)
1951 {
1952 }
1953
1954 void setup_sysctl_set(struct ctl_table_set *p,
1955         struct ctl_table_set *parent,
1956         int (*is_seen)(struct ctl_table_set *))
1957 {
1958 }
1959
1960 void sysctl_head_put(struct ctl_table_header *head)
1961 {
1962 }
1963
1964 #endif /* CONFIG_SYSCTL */
1965
1966 /*
1967  * /proc/sys support
1968  */
1969
1970 #ifdef CONFIG_PROC_SYSCTL
1971
1972 static int _proc_do_string(void* data, int maxlen, int write,
1973                            void __user *buffer,
1974                            size_t *lenp, loff_t *ppos)
1975 {
1976         size_t len;
1977         char __user *p;
1978         char c;
1979
1980         if (!data || !maxlen || !*lenp) {
1981                 *lenp = 0;
1982                 return 0;
1983         }
1984
1985         if (write) {
1986                 len = 0;
1987                 p = buffer;
1988                 while (len < *lenp) {
1989                         if (get_user(c, p++))
1990                                 return -EFAULT;
1991                         if (c == 0 || c == '\n')
1992                                 break;
1993                         len++;
1994                 }
1995                 if (len >= maxlen)
1996                         len = maxlen-1;
1997                 if(copy_from_user(data, buffer, len))
1998                         return -EFAULT;
1999                 ((char *) data)[len] = 0;
2000                 *ppos += *lenp;
2001         } else {
2002                 len = strlen(data);
2003                 if (len > maxlen)
2004                         len = maxlen;
2005
2006                 if (*ppos > len) {
2007                         *lenp = 0;
2008                         return 0;
2009                 }
2010
2011                 data += *ppos;
2012                 len  -= *ppos;
2013
2014                 if (len > *lenp)
2015                         len = *lenp;
2016                 if (len)
2017                         if(copy_to_user(buffer, data, len))
2018                                 return -EFAULT;
2019                 if (len < *lenp) {
2020                         if(put_user('\n', ((char __user *) buffer) + len))
2021                                 return -EFAULT;
2022                         len++;
2023                 }
2024                 *lenp = len;
2025                 *ppos += len;
2026         }
2027         return 0;
2028 }
2029
2030 /**
2031  * proc_dostring - read a string sysctl
2032  * @table: the sysctl table
2033  * @write: %TRUE if this is a write to the sysctl file
2034  * @buffer: the user buffer
2035  * @lenp: the size of the user buffer
2036  * @ppos: file position
2037  *
2038  * Reads/writes a string from/to the user buffer. If the kernel
2039  * buffer provided is not large enough to hold the string, the
2040  * string is truncated. The copied string is %NULL-terminated.
2041  * If the string is being read by the user process, it is copied
2042  * and a newline '\n' is added. It is truncated if the buffer is
2043  * not large enough.
2044  *
2045  * Returns 0 on success.
2046  */
2047 int proc_dostring(struct ctl_table *table, int write,
2048                   void __user *buffer, size_t *lenp, loff_t *ppos)
2049 {
2050         return _proc_do_string(table->data, table->maxlen, write,
2051                                buffer, lenp, ppos);
2052 }
2053
2054
2055 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2056                                  int *valp,
2057                                  int write, void *data)
2058 {
2059         if (write) {
2060                 *valp = *negp ? -*lvalp : *lvalp;
2061         } else {
2062                 int val = *valp;
2063                 if (val < 0) {
2064                         *negp = -1;
2065                         *lvalp = (unsigned long)-val;
2066                 } else {
2067                         *negp = 0;
2068                         *lvalp = (unsigned long)val;
2069                 }
2070         }
2071         return 0;
2072 }
2073
2074 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2075                   int write, void __user *buffer,
2076                   size_t *lenp, loff_t *ppos,
2077                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2078                               int write, void *data),
2079                   void *data)
2080 {
2081 #define TMPBUFLEN 21
2082         int *i, vleft, first = 1, neg;
2083         unsigned long lval;
2084         size_t left, len;
2085
2086         char buf[TMPBUFLEN], *p;
2087         char __user *s = buffer;
2088
2089         if (!tbl_data || !table->maxlen || !*lenp ||
2090             (*ppos && !write)) {
2091                 *lenp = 0;
2092                 return 0;
2093         }
2094
2095         i = (int *) tbl_data;
2096         vleft = table->maxlen / sizeof(*i);
2097         left = *lenp;
2098
2099         if (!conv)
2100                 conv = do_proc_dointvec_conv;
2101
2102         for (; left && vleft--; i++, first=0) {
2103                 if (write) {
2104                         while (left) {
2105                                 char c;
2106                                 if (get_user(c, s))
2107                                         return -EFAULT;
2108                                 if (!isspace(c))
2109                                         break;
2110                                 left--;
2111                                 s++;
2112                         }
2113                         if (!left)
2114                                 break;
2115                         neg = 0;
2116                         len = left;
2117                         if (len > sizeof(buf) - 1)
2118                                 len = sizeof(buf) - 1;
2119                         if (copy_from_user(buf, s, len))
2120                                 return -EFAULT;
2121                         buf[len] = 0;
2122                         p = buf;
2123                         if (*p == '-' && left > 1) {
2124                                 neg = 1;
2125                                 p++;
2126                         }
2127                         if (*p < '0' || *p > '9')
2128                                 break;
2129
2130                         lval = simple_strtoul(p, &p, 0);
2131
2132                         len = p-buf;
2133                         if ((len < left) && *p && !isspace(*p))
2134                                 break;
2135                         s += len;
2136                         left -= len;
2137
2138                         if (conv(&neg, &lval, i, 1, data))
2139                                 break;
2140                 } else {
2141                         p = buf;
2142                         if (!first)
2143                                 *p++ = '\t';
2144
2145                         if (conv(&neg, &lval, i, 0, data))
2146                                 break;
2147
2148                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
2149                         len = strlen(buf);
2150                         if (len > left)
2151                                 len = left;
2152                         if(copy_to_user(s, buf, len))
2153                                 return -EFAULT;
2154                         left -= len;
2155                         s += len;
2156                 }
2157         }
2158
2159         if (!write && !first && left) {
2160                 if(put_user('\n', s))
2161                         return -EFAULT;
2162                 left--, s++;
2163         }
2164         if (write) {
2165                 while (left) {
2166                         char c;
2167                         if (get_user(c, s++))
2168                                 return -EFAULT;
2169                         if (!isspace(c))
2170                                 break;
2171                         left--;
2172                 }
2173         }
2174         if (write && first)
2175                 return -EINVAL;
2176         *lenp -= left;
2177         *ppos += *lenp;
2178         return 0;
2179 #undef TMPBUFLEN
2180 }
2181
2182 static int do_proc_dointvec(struct ctl_table *table, int write,
2183                   void __user *buffer, size_t *lenp, loff_t *ppos,
2184                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2185                               int write, void *data),
2186                   void *data)
2187 {
2188         return __do_proc_dointvec(table->data, table, write,
2189                         buffer, lenp, ppos, conv, data);
2190 }
2191
2192 /**
2193  * proc_dointvec - read a vector of integers
2194  * @table: the sysctl table
2195  * @write: %TRUE if this is a write to the sysctl file
2196  * @buffer: the user buffer
2197  * @lenp: the size of the user buffer
2198  * @ppos: file position
2199  *
2200  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2201  * values from/to the user buffer, treated as an ASCII string.
2202  *
2203  * Returns 0 on success.
2204  */
2205 int proc_dointvec(struct ctl_table *table, int write,
2206                      void __user *buffer, size_t *lenp, loff_t *ppos)
2207 {
2208     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2209                             NULL,NULL);
2210 }
2211
2212 /*
2213  * Taint values can only be increased
2214  * This means we can safely use a temporary.
2215  */
2216 static int proc_taint(struct ctl_table *table, int write,
2217                                void __user *buffer, size_t *lenp, loff_t *ppos)
2218 {
2219         struct ctl_table t;
2220         unsigned long tmptaint = get_taint();
2221         int err;
2222
2223         if (write && !capable(CAP_SYS_ADMIN))
2224                 return -EPERM;
2225
2226         t = *table;
2227         t.data = &tmptaint;
2228         err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2229         if (err < 0)
2230                 return err;
2231
2232         if (write) {
2233                 /*
2234                  * Poor man's atomic or. Not worth adding a primitive
2235                  * to everyone's atomic.h for this
2236                  */
2237                 int i;
2238                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2239                         if ((tmptaint >> i) & 1)
2240                                 add_taint(i);
2241                 }
2242         }
2243
2244         return err;
2245 }
2246
2247 struct do_proc_dointvec_minmax_conv_param {
2248         int *min;
2249         int *max;
2250 };
2251
2252 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2253                                         int *valp,
2254                                         int write, void *data)
2255 {
2256         struct do_proc_dointvec_minmax_conv_param *param = data;
2257         if (write) {
2258                 int val = *negp ? -*lvalp : *lvalp;
2259                 if ((param->min && *param->min > val) ||
2260                     (param->max && *param->max < val))
2261                         return -EINVAL;
2262                 *valp = val;
2263         } else {
2264                 int val = *valp;
2265                 if (val < 0) {
2266                         *negp = -1;
2267                         *lvalp = (unsigned long)-val;
2268                 } else {
2269                         *negp = 0;
2270                         *lvalp = (unsigned long)val;
2271                 }
2272         }
2273         return 0;
2274 }
2275
2276 /**
2277  * proc_dointvec_minmax - read a vector of integers with min/max values
2278  * @table: the sysctl table
2279  * @write: %TRUE if this is a write to the sysctl file
2280  * @buffer: the user buffer
2281  * @lenp: the size of the user buffer
2282  * @ppos: file position
2283  *
2284  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2285  * values from/to the user buffer, treated as an ASCII string.
2286  *
2287  * This routine will ensure the values are within the range specified by
2288  * table->extra1 (min) and table->extra2 (max).
2289  *
2290  * Returns 0 on success.
2291  */
2292 int proc_dointvec_minmax(struct ctl_table *table, int write,
2293                   void __user *buffer, size_t *lenp, loff_t *ppos)
2294 {
2295         struct do_proc_dointvec_minmax_conv_param param = {
2296                 .min = (int *) table->extra1,
2297                 .max = (int *) table->extra2,
2298         };
2299         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2300                                 do_proc_dointvec_minmax_conv, &param);
2301 }
2302
2303 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2304                                      void __user *buffer,
2305                                      size_t *lenp, loff_t *ppos,
2306                                      unsigned long convmul,
2307                                      unsigned long convdiv)
2308 {
2309 #define TMPBUFLEN 21
2310         unsigned long *i, *min, *max, val;
2311         int vleft, first=1, neg;
2312         size_t len, left;
2313         char buf[TMPBUFLEN], *p;
2314         char __user *s = buffer;
2315
2316         if (!data || !table->maxlen || !*lenp ||
2317             (*ppos && !write)) {
2318                 *lenp = 0;
2319                 return 0;
2320         }
2321
2322         i = (unsigned long *) data;
2323         min = (unsigned long *) table->extra1;
2324         max = (unsigned long *) table->extra2;
2325         vleft = table->maxlen / sizeof(unsigned long);
2326         left = *lenp;
2327
2328         for (; left && vleft--; i++, min++, max++, first=0) {
2329                 if (write) {
2330                         while (left) {
2331                                 char c;
2332                                 if (get_user(c, s))
2333                                         return -EFAULT;
2334                                 if (!isspace(c))
2335                                         break;
2336                                 left--;
2337                                 s++;
2338                         }
2339                         if (!left)
2340                                 break;
2341                         neg = 0;
2342                         len = left;
2343                         if (len > TMPBUFLEN-1)
2344                                 len = TMPBUFLEN-1;
2345                         if (copy_from_user(buf, s, len))
2346                                 return -EFAULT;
2347                         buf[len] = 0;
2348                         p = buf;
2349                         if (*p == '-' && left > 1) {
2350                                 neg = 1;
2351                                 p++;
2352                         }
2353                         if (*p < '0' || *p > '9')
2354                                 break;
2355                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2356                         len = p-buf;
2357                         if ((len < left) && *p && !isspace(*p))
2358                                 break;
2359                         if (neg)
2360                                 val = -val;
2361                         s += len;
2362                         left -= len;
2363
2364                         if(neg)
2365                                 continue;
2366                         if ((min && val < *min) || (max && val > *max))
2367                                 continue;
2368                         *i = val;
2369                 } else {
2370                         p = buf;
2371                         if (!first)
2372                                 *p++ = '\t';
2373                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2374                         len = strlen(buf);
2375                         if (len > left)
2376                                 len = left;
2377                         if(copy_to_user(s, buf, len))
2378                                 return -EFAULT;
2379                         left -= len;
2380                         s += len;
2381                 }
2382         }
2383
2384         if (!write && !first && left) {
2385                 if(put_user('\n', s))
2386                         return -EFAULT;
2387                 left--, s++;
2388         }
2389         if (write) {
2390                 while (left) {
2391                         char c;
2392                         if (get_user(c, s++))
2393                                 return -EFAULT;
2394                         if (!isspace(c))
2395                                 break;
2396                         left--;
2397                 }
2398         }
2399         if (write && first)
2400                 return -EINVAL;
2401         *lenp -= left;
2402         *ppos += *lenp;
2403         return 0;
2404 #undef TMPBUFLEN
2405 }
2406
2407 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2408                                      void __user *buffer,
2409                                      size_t *lenp, loff_t *ppos,
2410                                      unsigned long convmul,
2411                                      unsigned long convdiv)
2412 {
2413         return __do_proc_doulongvec_minmax(table->data, table, write,
2414                         buffer, lenp, ppos, convmul, convdiv);
2415 }
2416
2417 /**
2418  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2419  * @table: the sysctl table
2420  * @write: %TRUE if this is a write to the sysctl file
2421  * @buffer: the user buffer
2422  * @lenp: the size of the user buffer
2423  * @ppos: file position
2424  *
2425  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2426  * values from/to the user buffer, treated as an ASCII string.
2427  *
2428  * This routine will ensure the values are within the range specified by
2429  * table->extra1 (min) and table->extra2 (max).
2430  *
2431  * Returns 0 on success.
2432  */
2433 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2434                            void __user *buffer, size_t *lenp, loff_t *ppos)
2435 {
2436     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2437 }
2438
2439 /**
2440  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2441  * @table: the sysctl table
2442  * @write: %TRUE if this is a write to the sysctl file
2443  * @buffer: the user buffer
2444  * @lenp: the size of the user buffer
2445  * @ppos: file position
2446  *
2447  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2448  * values from/to the user buffer, treated as an ASCII string. The values
2449  * are treated as milliseconds, and converted to jiffies when they are stored.
2450  *
2451  * This routine will ensure the values are within the range specified by
2452  * table->extra1 (min) and table->extra2 (max).
2453  *
2454  * Returns 0 on success.
2455  */
2456 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2457                                       void __user *buffer,
2458                                       size_t *lenp, loff_t *ppos)
2459 {
2460     return do_proc_doulongvec_minmax(table, write, buffer,
2461                                      lenp, ppos, HZ, 1000l);
2462 }
2463
2464
2465 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2466                                          int *valp,
2467                                          int write, void *data)
2468 {
2469         if (write) {
2470                 if (*lvalp > LONG_MAX / HZ)
2471                         return 1;
2472                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2473         } else {
2474                 int val = *valp;
2475                 unsigned long lval;
2476                 if (val < 0) {
2477                         *negp = -1;
2478                         lval = (unsigned long)-val;
2479                 } else {
2480                         *negp = 0;
2481                         lval = (unsigned long)val;
2482                 }
2483                 *lvalp = lval / HZ;
2484         }
2485         return 0;
2486 }
2487
2488 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2489                                                 int *valp,
2490                                                 int write, void *data)
2491 {
2492         if (write) {
2493                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2494                         return 1;
2495                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2496         } else {
2497                 int val = *valp;
2498                 unsigned long lval;
2499                 if (val < 0) {
2500                         *negp = -1;
2501                         lval = (unsigned long)-val;
2502                 } else {
2503                         *negp = 0;
2504                         lval = (unsigned long)val;
2505                 }
2506                 *lvalp = jiffies_to_clock_t(lval);
2507         }
2508         return 0;
2509 }
2510
2511 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2512                                             int *valp,
2513                                             int write, void *data)
2514 {
2515         if (write) {
2516                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2517         } else {
2518                 int val = *valp;
2519                 unsigned long lval;
2520                 if (val < 0) {
2521                         *negp = -1;
2522                         lval = (unsigned long)-val;
2523                 } else {
2524                         *negp = 0;
2525                         lval = (unsigned long)val;
2526                 }
2527                 *lvalp = jiffies_to_msecs(lval);
2528         }
2529         return 0;
2530 }
2531
2532 /**
2533  * proc_dointvec_jiffies - read a vector of integers as seconds
2534  * @table: the sysctl table
2535  * @write: %TRUE if this is a write to the sysctl file
2536  * @buffer: the user buffer
2537  * @lenp: the size of the user buffer
2538  * @ppos: file position
2539  *
2540  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2541  * values from/to the user buffer, treated as an ASCII string.
2542  * The values read are assumed to be in seconds, and are converted into
2543  * jiffies.
2544  *
2545  * Returns 0 on success.
2546  */
2547 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2548                           void __user *buffer, size_t *lenp, loff_t *ppos)
2549 {
2550     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2551                             do_proc_dointvec_jiffies_conv,NULL);
2552 }
2553
2554 /**
2555  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2556  * @table: the sysctl table
2557  * @write: %TRUE if this is a write to the sysctl file
2558  * @buffer: the user buffer
2559  * @lenp: the size of the user buffer
2560  * @ppos: pointer to the file position
2561  *
2562  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2563  * values from/to the user buffer, treated as an ASCII string.
2564  * The values read are assumed to be in 1/USER_HZ seconds, and
2565  * are converted into jiffies.
2566  *
2567  * Returns 0 on success.
2568  */
2569 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2570                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2571 {
2572     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2573                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2574 }
2575
2576 /**
2577  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2578  * @table: the sysctl table
2579  * @write: %TRUE if this is a write to the sysctl file
2580  * @buffer: the user buffer
2581  * @lenp: the size of the user buffer
2582  * @ppos: file position
2583  * @ppos: the current position in the file
2584  *
2585  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2586  * values from/to the user buffer, treated as an ASCII string.
2587  * The values read are assumed to be in 1/1000 seconds, and
2588  * are converted into jiffies.
2589  *
2590  * Returns 0 on success.
2591  */
2592 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2593                              void __user *buffer, size_t *lenp, loff_t *ppos)
2594 {
2595         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2596                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2597 }
2598
2599 static int proc_do_cad_pid(struct ctl_table *table, int write,
2600                            void __user *buffer, size_t *lenp, loff_t *ppos)
2601 {
2602         struct pid *new_pid;
2603         pid_t tmp;
2604         int r;
2605
2606         tmp = pid_vnr(cad_pid);
2607
2608         r = __do_proc_dointvec(&tmp, table, write, buffer,
2609                                lenp, ppos, NULL, NULL);
2610         if (r || !write)
2611                 return r;
2612
2613         new_pid = find_get_pid(tmp);
2614         if (!new_pid)
2615                 return -ESRCH;
2616
2617         put_pid(xchg(&cad_pid, new_pid));
2618         return 0;
2619 }
2620
2621 #else /* CONFIG_PROC_FS */
2622
2623 int proc_dostring(struct ctl_table *table, int write,
2624                   void __user *buffer, size_t *lenp, loff_t *ppos)
2625 {
2626         return -ENOSYS;
2627 }
2628
2629 int proc_dointvec(struct ctl_table *table, int write,
2630                   void __user *buffer, size_t *lenp, loff_t *ppos)
2631 {
2632         return -ENOSYS;
2633 }
2634
2635 int proc_dointvec_minmax(struct ctl_table *table, int write,
2636                     void __user *buffer, size_t *lenp, loff_t *ppos)
2637 {
2638         return -ENOSYS;
2639 }
2640
2641 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2642                     void __user *buffer, size_t *lenp, loff_t *ppos)
2643 {
2644         return -ENOSYS;
2645 }
2646
2647 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2648                     void __user *buffer, size_t *lenp, loff_t *ppos)
2649 {
2650         return -ENOSYS;
2651 }
2652
2653 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2654                              void __user *buffer, size_t *lenp, loff_t *ppos)
2655 {
2656         return -ENOSYS;
2657 }
2658
2659 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2660                     void __user *buffer, size_t *lenp, loff_t *ppos)
2661 {
2662         return -ENOSYS;
2663 }
2664
2665 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2666                                       void __user *buffer,
2667                                       size_t *lenp, loff_t *ppos)
2668 {
2669     return -ENOSYS;
2670 }
2671
2672
2673 #endif /* CONFIG_PROC_FS */
2674
2675 /*
2676  * No sense putting this after each symbol definition, twice,
2677  * exception granted :-)
2678  */
2679 EXPORT_SYMBOL(proc_dointvec);
2680 EXPORT_SYMBOL(proc_dointvec_jiffies);
2681 EXPORT_SYMBOL(proc_dointvec_minmax);
2682 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2683 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2684 EXPORT_SYMBOL(proc_dostring);
2685 EXPORT_SYMBOL(proc_doulongvec_minmax);
2686 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2687 EXPORT_SYMBOL(register_sysctl_table);
2688 EXPORT_SYMBOL(register_sysctl_paths);
2689 EXPORT_SYMBOL(unregister_sysctl_table);