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   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/mm.h>
  23 #include <linux/swap.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/security.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/kmemcheck.h>
  31 #include <linux/smp_lock.h>
  32 #include <linux/fs.h>
  33 #include <linux/init.h>
  34 #include <linux/kernel.h>
  35 #include <linux/kobject.h>
  36 #include <linux/net.h>
  37 #include <linux/sysrq.h>
  38 #include <linux/highuid.h>
  39 #include <linux/writeback.h>
  40 #include <linux/hugetlb.h>
  41 #include <linux/initrd.h>
  42 #include <linux/key.h>
  43 #include <linux/times.h>
  44 #include <linux/limits.h>
  45 #include <linux/dcache.h>
  46 #include <linux/syscalls.h>
  47 #include <linux/vmstat.h>
  48 #include <linux/nfs_fs.h>
  49 #include <linux/acpi.h>
  50 #include <linux/reboot.h>
  51 #include <linux/ftrace.h>
  52 #include <linux/slow-work.h>
  53 #include <linux/perf_counter.h>
  54
  55 #include <asm/uaccess.h>
  56 #include <asm/processor.h>
  57
  58 #ifdef CONFIG_X86
  59 #include <asm/nmi.h>
  60 #include <asm/stacktrace.h>
  61 #include <asm/io.h>
  62 #endif
  63
  64 static int deprecated_sysctl_warning(struct __sysctl_args *args);
  65
  66 #if defined(CONFIG_SYSCTL)
  67
  68 /* External variables not in a header file. */
  69 extern int C_A_D;
  70 extern int print_fatal_signals;
  71 extern int sysctl_overcommit_memory;
  72 extern int sysctl_overcommit_ratio;
  73 extern int sysctl_panic_on_oom;
  74 extern int sysctl_oom_kill_allocating_task;
  75 extern int sysctl_oom_dump_tasks;
  76 extern int max_threads;
  77 extern int core_uses_pid;
  78 extern int suid_dumpable;
  79 extern char core_pattern[];
  80 extern int pid_max;
  81 extern int min_free_kbytes;
  82 extern int pid_max_min, pid_max_max;
  83 extern int sysctl_drop_caches;
  84 extern int percpu_pagelist_fraction;
  85 extern int compat_log;
  86 extern int latencytop_enabled;
  87 extern int sysctl_nr_open_min, sysctl_nr_open_max;
  88 #ifndef CONFIG_MMU
  89 extern int sysctl_nr_trim_pages;
  90 #endif
  91 #ifdef CONFIG_RCU_TORTURE_TEST
  92 extern int rcutorture_runnable;
  93 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
  94 #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
 110 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
 111 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
 112
 113 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 114 static int maxolduid = 65535;
 115 static int minolduid;
 116 static int min_percpu_pagelist_fract = 8;
 117
 118 static int ngroups_max = NGROUPS_MAX;
 119
 120 #ifdef CONFIG_MODULES
 121 extern char modprobe_path[];
 122 extern int modules_disabled;
 123 #endif
 124 #ifdef CONFIG_CHR_DEV_SG
 125 extern int sg_big_buff;
 126 #endif
 127
 128 #ifdef CONFIG_SPARC
 129 #include <asm/system.h>
 130 #endif
 131
 132 #ifdef CONFIG_SPARC64
 133 extern int sysctl_tsb_ratio;
 134 #endif
 135
 136 #ifdef __hppa__
 137 extern int pwrsw_enabled;
 138 extern int unaligned_enabled;
 139 #endif
 140
 141 #ifdef CONFIG_S390
 142 #ifdef CONFIG_MATHEMU
 143 extern int sysctl_ieee_emulation_warnings;
 144 #endif
 145 extern int sysctl_userprocess_debug;
 146 extern int spin_retry;
 147 #endif
 148
 149 #ifdef CONFIG_BSD_PROCESS_ACCT
 150 extern int acct_parm[];
 151 #endif
 152
 153 #ifdef CONFIG_IA64
 154 extern int no_unaligned_warning;
 155 extern int unaligned_dump_stack;
 156 #endif
 157
 158 #ifdef CONFIG_RT_MUTEXES
 159 extern int max_lock_depth;
 160 #endif
 161
 162 #ifdef CONFIG_PROC_SYSCTL
 163 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
 164                   void __user *buffer, size_t *lenp, loff_t *ppos);
 165 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
 166                                void __user *buffer, size_t *lenp, loff_t *ppos);
 167 #endif
 168
 169 static struct ctl_table root_table[];
 170 static struct ctl_table_root sysctl_table_root;
 171 static struct ctl_table_header root_table_header = {
 172         .count = 1,
 173         .ctl_table = root_table,
 174         .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
 175         .root = &sysctl_table_root,
 176         .set = &sysctl_table_root.default_set,
 177 };
 178 static struct ctl_table_root sysctl_table_root = {
 179         .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
 180         .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
 181 };
 182
 183 static struct ctl_table kern_table[];
 184 static struct ctl_table vm_table[];
 185 static struct ctl_table fs_table[];
 186 static struct ctl_table debug_table[];
 187 static struct ctl_table dev_table[];
 188 extern struct ctl_table random_table[];
 189 #ifdef CONFIG_INOTIFY_USER
 190 extern struct ctl_table inotify_table[];
 191 #endif
 192 #ifdef CONFIG_EPOLL
 193 extern struct ctl_table epoll_table[];
 194 #endif
 195
 196 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 197 int sysctl_legacy_va_layout;
 198 #endif
 199
 200 extern int prove_locking;
 201 extern int lock_stat;
 202
 203 /* The default sysctl tables: */
 204
 205 static struct ctl_table root_table[] = {
 206         {
 207                 .ctl_name       = CTL_KERN,
 208                 .procname       = "kernel",
 209                 .mode           = 0555,
 210                 .child          = kern_table,
 211         },
 212         {
 213                 .ctl_name       = CTL_VM,
 214                 .procname       = "vm",
 215                 .mode           = 0555,
 216                 .child          = vm_table,
 217         },
 218         {
 219                 .ctl_name       = CTL_FS,
 220                 .procname       = "fs",
 221                 .mode           = 0555,
 222                 .child          = fs_table,
 223         },
 224         {
 225                 .ctl_name       = CTL_DEBUG,
 226                 .procname       = "debug",
 227                 .mode           = 0555,
 228                 .child          = debug_table,
 229         },
 230         {
 231                 .ctl_name       = CTL_DEV,
 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         { .ctl_name = 0 }
 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 #endif
 249
 250 static struct ctl_table kern_table[] = {
 251         {
 252                 .ctl_name       = CTL_UNNUMBERED,
 253                 .procname       = "sched_child_runs_first",
 254                 .data           = &sysctl_sched_child_runs_first,
 255                 .maxlen         = sizeof(unsigned int),
 256                 .mode           = 0644,
 257                 .proc_handler   = &proc_dointvec,
 258         },
 259 #ifdef CONFIG_SCHED_DEBUG
 260         {
 261                 .ctl_name       = CTL_UNNUMBERED,
 262                 .procname       = "sched_min_granularity_ns",
 263                 .data           = &sysctl_sched_min_granularity,
 264                 .maxlen         = sizeof(unsigned int),
 265                 .mode           = 0644,
 266                 .proc_handler   = &sched_nr_latency_handler,
 267                 .strategy       = &sysctl_intvec,
 268                 .extra1         = &min_sched_granularity_ns,
 269                 .extra2         = &max_sched_granularity_ns,
 270         },
 271         {
 272                 .ctl_name       = CTL_UNNUMBERED,
 273                 .procname       = "sched_latency_ns",
 274                 .data           = &sysctl_sched_latency,
 275                 .maxlen         = sizeof(unsigned int),
 276                 .mode           = 0644,
 277                 .proc_handler   = &sched_nr_latency_handler,
 278                 .strategy       = &sysctl_intvec,
 279                 .extra1         = &min_sched_granularity_ns,
 280                 .extra2         = &max_sched_granularity_ns,
 281         },
 282         {
 283                 .ctl_name       = CTL_UNNUMBERED,
 284                 .procname       = "sched_wakeup_granularity_ns",
 285                 .data           = &sysctl_sched_wakeup_granularity,
 286                 .maxlen         = sizeof(unsigned int),
 287                 .mode           = 0644,
 288                 .proc_handler   = &proc_dointvec_minmax,
 289                 .strategy       = &sysctl_intvec,
 290                 .extra1         = &min_wakeup_granularity_ns,
 291                 .extra2         = &max_wakeup_granularity_ns,
 292         },
 293         {
 294                 .ctl_name       = CTL_UNNUMBERED,
 295                 .procname       = "sched_shares_ratelimit",
 296                 .data           = &sysctl_sched_shares_ratelimit,
 297                 .maxlen         = sizeof(unsigned int),
 298                 .mode           = 0644,
 299                 .proc_handler   = &proc_dointvec,
 300         },
 301         {
 302                 .ctl_name       = CTL_UNNUMBERED,
 303                 .procname       = "sched_shares_thresh",
 304                 .data           = &sysctl_sched_shares_thresh,
 305                 .maxlen         = sizeof(unsigned int),
 306                 .mode           = 0644,
 307                 .proc_handler   = &proc_dointvec_minmax,
 308                 .strategy       = &sysctl_intvec,
 309                 .extra1         = &zero,
 310         },
 311         {
 312                 .ctl_name       = CTL_UNNUMBERED,
 313                 .procname       = "sched_features",
 314                 .data           = &sysctl_sched_features,
 315                 .maxlen         = sizeof(unsigned int),
 316                 .mode           = 0644,
 317                 .proc_handler   = &proc_dointvec,
 318         },
 319         {
 320                 .ctl_name       = CTL_UNNUMBERED,
 321                 .procname       = "sched_migration_cost",
 322                 .data           = &sysctl_sched_migration_cost,
 323                 .maxlen         = sizeof(unsigned int),
 324                 .mode           = 0644,
 325                 .proc_handler   = &proc_dointvec,
 326         },
 327         {
 328                 .ctl_name       = CTL_UNNUMBERED,
 329                 .procname       = "sched_nr_migrate",
 330                 .data           = &sysctl_sched_nr_migrate,
 331                 .maxlen         = sizeof(unsigned int),
 332                 .mode           = 0644,
 333                 .proc_handler   = &proc_dointvec,
 334         },
 335         {
 336                 .ctl_name       = CTL_UNNUMBERED,
 337                 .procname       = "sched_time_avg",
 338                 .data           = &sysctl_sched_time_avg,
 339                 .maxlen         = sizeof(unsigned int),
 340                 .mode           = 0644,
 341                 .proc_handler   = &proc_dointvec,
 342         },
 343         {
 344                 .ctl_name       = CTL_UNNUMBERED,
 345                 .procname       = "timer_migration",
 346                 .data           = &sysctl_timer_migration,
 347                 .maxlen         = sizeof(unsigned int),
 348                 .mode           = 0644,
 349                 .proc_handler   = &proc_dointvec_minmax,
 350                 .strategy       = &sysctl_intvec,
 351                 .extra1         = &zero,
 352                 .extra2         = &one,
 353         },
 354 #endif
 355         {
 356                 .ctl_name       = CTL_UNNUMBERED,
 357                 .procname       = "sched_rt_period_us",
 358                 .data           = &sysctl_sched_rt_period,
 359                 .maxlen         = sizeof(unsigned int),
 360                 .mode           = 0644,
 361                 .proc_handler   = &sched_rt_handler,
 362         },
 363         {
 364                 .ctl_name       = CTL_UNNUMBERED,
 365                 .procname       = "sched_rt_runtime_us",
 366                 .data           = &sysctl_sched_rt_runtime,
 367                 .maxlen         = sizeof(int),
 368                 .mode           = 0644,
 369                 .proc_handler   = &sched_rt_handler,
 370         },
 371         {
 372                 .ctl_name       = CTL_UNNUMBERED,
 373                 .procname       = "sched_compat_yield",
 374                 .data           = &sysctl_sched_compat_yield,
 375                 .maxlen         = sizeof(unsigned int),
 376                 .mode           = 0644,
 377                 .proc_handler   = &proc_dointvec,
 378         },
 379 #ifdef CONFIG_PROVE_LOCKING
 380         {
 381                 .ctl_name       = CTL_UNNUMBERED,
 382                 .procname       = "prove_locking",
 383                 .data           = &prove_locking,
 384                 .maxlen         = sizeof(int),
 385                 .mode           = 0644,
 386                 .proc_handler   = &proc_dointvec,
 387         },
 388 #endif
 389 #ifdef CONFIG_LOCK_STAT
 390         {
 391                 .ctl_name       = CTL_UNNUMBERED,
 392                 .procname       = "lock_stat",
 393                 .data           = &lock_stat,
 394                 .maxlen         = sizeof(int),
 395                 .mode           = 0644,
 396                 .proc_handler   = &proc_dointvec,
 397         },
 398 #endif
 399         {
 400                 .ctl_name       = KERN_PANIC,
 401                 .procname       = "panic",
 402                 .data           = &panic_timeout,
 403                 .maxlen         = sizeof(int),
 404                 .mode           = 0644,
 405                 .proc_handler   = &proc_dointvec,
 406         },
 407         {
 408                 .ctl_name       = KERN_CORE_USES_PID,
 409                 .procname       = "core_uses_pid",
 410                 .data           = &core_uses_pid,
 411                 .maxlen         = sizeof(int),
 412                 .mode           = 0644,
 413                 .proc_handler   = &proc_dointvec,
 414         },
 415         {
 416                 .ctl_name       = KERN_CORE_PATTERN,
 417                 .procname       = "core_pattern",
 418                 .data           = core_pattern,
 419                 .maxlen         = CORENAME_MAX_SIZE,
 420                 .mode           = 0644,
 421                 .proc_handler   = &proc_dostring,
 422                 .strategy       = &sysctl_string,
 423         },
 424 #ifdef CONFIG_PROC_SYSCTL
 425         {
 426                 .procname       = "tainted",
 427                 .maxlen         = sizeof(long),
 428                 .mode           = 0644,
 429                 .proc_handler   = &proc_taint,
 430         },
 431 #endif
 432 #ifdef CONFIG_LATENCYTOP
 433         {
 434                 .procname       = "latencytop",
 435                 .data           = &latencytop_enabled,
 436                 .maxlen         = sizeof(int),
 437                 .mode           = 0644,
 438                 .proc_handler   = &proc_dointvec,
 439         },
 440 #endif
 441 #ifdef CONFIG_BLK_DEV_INITRD
 442         {
 443                 .ctl_name       = KERN_REALROOTDEV,
 444                 .procname       = "real-root-dev",
 445                 .data           = &real_root_dev,
 446                 .maxlen         = sizeof(int),
 447                 .mode           = 0644,
 448                 .proc_handler   = &proc_dointvec,
 449         },
 450 #endif
 451         {
 452                 .ctl_name       = CTL_UNNUMBERED,
 453                 .procname       = "print-fatal-signals",
 454                 .data           = &print_fatal_signals,
 455                 .maxlen         = sizeof(int),
 456                 .mode           = 0644,
 457                 .proc_handler   = &proc_dointvec,
 458         },
 459 #ifdef CONFIG_SPARC
 460         {
 461                 .ctl_name       = KERN_SPARC_REBOOT,
 462                 .procname       = "reboot-cmd",
 463                 .data           = reboot_command,
 464                 .maxlen         = 256,
 465                 .mode           = 0644,
 466                 .proc_handler   = &proc_dostring,
 467                 .strategy       = &sysctl_string,
 468         },
 469         {
 470                 .ctl_name       = KERN_SPARC_STOP_A,
 471                 .procname       = "stop-a",
 472                 .data           = &stop_a_enabled,
 473                 .maxlen         = sizeof (int),
 474                 .mode           = 0644,
 475                 .proc_handler   = &proc_dointvec,
 476         },
 477         {
 478                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 479                 .procname       = "scons-poweroff",
 480                 .data           = &scons_pwroff,
 481                 .maxlen         = sizeof (int),
 482                 .mode           = 0644,
 483                 .proc_handler   = &proc_dointvec,
 484         },
 485 #endif
 486 #ifdef CONFIG_SPARC64
 487         {
 488                 .ctl_name       = CTL_UNNUMBERED,
 489                 .procname       = "tsb-ratio",
 490                 .data           = &sysctl_tsb_ratio,
 491                 .maxlen         = sizeof (int),
 492                 .mode           = 0644,
 493                 .proc_handler   = &proc_dointvec,
 494         },
 495 #endif
 496 #ifdef __hppa__
 497         {
 498                 .ctl_name       = KERN_HPPA_PWRSW,
 499                 .procname       = "soft-power",
 500                 .data           = &pwrsw_enabled,
 501                 .maxlen         = sizeof (int),
 502                 .mode           = 0644,
 503                 .proc_handler   = &proc_dointvec,
 504         },
 505         {
 506                 .ctl_name       = KERN_HPPA_UNALIGNED,
 507                 .procname       = "unaligned-trap",
 508                 .data           = &unaligned_enabled,
 509                 .maxlen         = sizeof (int),
 510                 .mode           = 0644,
 511                 .proc_handler   = &proc_dointvec,
 512         },
 513 #endif
 514         {
 515                 .ctl_name       = KERN_CTLALTDEL,
 516                 .procname       = "ctrl-alt-del",
 517                 .data           = &C_A_D,
 518                 .maxlen         = sizeof(int),
 519                 .mode           = 0644,
 520                 .proc_handler   = &proc_dointvec,
 521         },
 522 #ifdef CONFIG_FUNCTION_TRACER
 523         {
 524                 .ctl_name       = CTL_UNNUMBERED,
 525                 .procname       = "ftrace_enabled",
 526                 .data           = &ftrace_enabled,
 527                 .maxlen         = sizeof(int),
 528                 .mode           = 0644,
 529                 .proc_handler   = &ftrace_enable_sysctl,
 530         },
 531 #endif
 532 #ifdef CONFIG_STACK_TRACER
 533         {
 534                 .ctl_name       = CTL_UNNUMBERED,
 535                 .procname       = "stack_tracer_enabled",
 536                 .data           = &stack_tracer_enabled,
 537                 .maxlen         = sizeof(int),
 538                 .mode           = 0644,
 539                 .proc_handler   = &stack_trace_sysctl,
 540         },
 541 #endif
 542 #ifdef CONFIG_TRACING
 543         {
 544                 .ctl_name       = CTL_UNNUMBERED,
 545                 .procname       = "ftrace_dump_on_oops",
 546                 .data           = &ftrace_dump_on_oops,
 547                 .maxlen         = sizeof(int),
 548                 .mode           = 0644,
 549                 .proc_handler   = &proc_dointvec,
 550         },
 551 #endif
 552 #ifdef CONFIG_MODULES
 553         {
 554                 .ctl_name       = KERN_MODPROBE,
 555                 .procname       = "modprobe",
 556                 .data           = &modprobe_path,
 557                 .maxlen         = KMOD_PATH_LEN,
 558                 .mode           = 0644,
 559                 .proc_handler   = &proc_dostring,
 560                 .strategy       = &sysctl_string,
 561         },
 562         {
 563                 .ctl_name       = CTL_UNNUMBERED,
 564                 .procname       = "modules_disabled",
 565                 .data           = &modules_disabled,
 566                 .maxlen         = sizeof(int),
 567                 .mode           = 0644,
 568                 /* only handle a transition from default "0" to "1" */
 569                 .proc_handler   = &proc_dointvec_minmax,
 570                 .extra1         = &one,
 571                 .extra2         = &one,
 572         },
 573 #endif
 574 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 575         {
 576                 .ctl_name       = KERN_HOTPLUG,
 577                 .procname       = "hotplug",
 578                 .data           = &uevent_helper,
 579                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 580                 .mode           = 0644,
 581                 .proc_handler   = &proc_dostring,
 582                 .strategy       = &sysctl_string,
 583         },
 584 #endif
 585 #ifdef CONFIG_CHR_DEV_SG
 586         {
 587                 .ctl_name       = KERN_SG_BIG_BUFF,
 588                 .procname       = "sg-big-buff",
 589                 .data           = &sg_big_buff,
 590                 .maxlen         = sizeof (int),
 591                 .mode           = 0444,
 592                 .proc_handler   = &proc_dointvec,
 593         },
 594 #endif
 595 #ifdef CONFIG_BSD_PROCESS_ACCT
 596         {
 597                 .ctl_name       = KERN_ACCT,
 598                 .procname       = "acct",
 599                 .data           = &acct_parm,
 600                 .maxlen         = 3*sizeof(int),
 601                 .mode           = 0644,
 602                 .proc_handler   = &proc_dointvec,
 603         },
 604 #endif
 605 #ifdef CONFIG_MAGIC_SYSRQ
 606         {
 607                 .ctl_name       = KERN_SYSRQ,
 608                 .procname       = "sysrq",
 609                 .data           = &__sysrq_enabled,
 610                 .maxlen         = sizeof (int),
 611                 .mode           = 0644,
 612                 .proc_handler   = &proc_dointvec,
 613         },
 614 #endif
 615 #ifdef CONFIG_PROC_SYSCTL
 616         {
 617                 .procname       = "cad_pid",
 618                 .data           = NULL,
 619                 .maxlen         = sizeof (int),
 620                 .mode           = 0600,
 621                 .proc_handler   = &proc_do_cad_pid,
 622         },
 623 #endif
 624         {
 625                 .ctl_name       = KERN_MAX_THREADS,
 626                 .procname       = "threads-max",
 627                 .data           = &max_threads,
 628                 .maxlen         = sizeof(int),
 629                 .mode           = 0644,
 630                 .proc_handler   = &proc_dointvec,
 631         },
 632         {
 633                 .ctl_name       = KERN_RANDOM,
 634                 .procname       = "random",
 635                 .mode           = 0555,
 636                 .child          = random_table,
 637         },
 638         {
 639                 .ctl_name       = KERN_OVERFLOWUID,
 640                 .procname       = "overflowuid",
 641                 .data           = &overflowuid,
 642                 .maxlen         = sizeof(int),
 643                 .mode           = 0644,
 644                 .proc_handler   = &proc_dointvec_minmax,
 645                 .strategy       = &sysctl_intvec,
 646                 .extra1         = &minolduid,
 647                 .extra2         = &maxolduid,
 648         },
 649         {
 650                 .ctl_name       = KERN_OVERFLOWGID,
 651                 .procname       = "overflowgid",
 652                 .data           = &overflowgid,
 653                 .maxlen         = sizeof(int),
 654                 .mode           = 0644,
 655                 .proc_handler   = &proc_dointvec_minmax,
 656                 .strategy       = &sysctl_intvec,
 657                 .extra1         = &minolduid,
 658                 .extra2         = &maxolduid,
 659         },
 660 #ifdef CONFIG_S390
 661 #ifdef CONFIG_MATHEMU
 662         {
 663                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 664                 .procname       = "ieee_emulation_warnings",
 665                 .data           = &sysctl_ieee_emulation_warnings,
 666                 .maxlen         = sizeof(int),
 667                 .mode           = 0644,
 668                 .proc_handler   = &proc_dointvec,
 669         },
 670 #endif
 671         {
 672                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 673                 .procname       = "userprocess_debug",
 674                 .data           = &sysctl_userprocess_debug,
 675                 .maxlen         = sizeof(int),
 676                 .mode           = 0644,
 677                 .proc_handler   = &proc_dointvec,
 678         },
 679 #endif
 680         {
 681                 .ctl_name       = KERN_PIDMAX,
 682                 .procname       = "pid_max",
 683                 .data           = &pid_max,
 684                 .maxlen         = sizeof (int),
 685                 .mode           = 0644,
 686                 .proc_handler   = &proc_dointvec_minmax,
 687                 .strategy       = sysctl_intvec,
 688                 .extra1         = &pid_max_min,
 689                 .extra2         = &pid_max_max,
 690         },
 691         {
 692                 .ctl_name       = KERN_PANIC_ON_OOPS,
 693                 .procname       = "panic_on_oops",
 694                 .data           = &panic_on_oops,
 695                 .maxlen         = sizeof(int),
 696                 .mode           = 0644,
 697                 .proc_handler   = &proc_dointvec,
 698         },
 699 #if defined CONFIG_PRINTK
 700         {
 701                 .ctl_name       = KERN_PRINTK,
 702                 .procname       = "printk",
 703                 .data           = &console_loglevel,
 704                 .maxlen         = 4*sizeof(int),
 705                 .mode           = 0644,
 706                 .proc_handler   = &proc_dointvec,
 707         },
 708         {
 709                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 710                 .procname       = "printk_ratelimit",
 711                 .data           = &printk_ratelimit_state.interval,
 712                 .maxlen         = sizeof(int),
 713                 .mode           = 0644,
 714                 .proc_handler   = &proc_dointvec_jiffies,
 715                 .strategy       = &sysctl_jiffies,
 716         },
 717         {
 718                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 719                 .procname       = "printk_ratelimit_burst",
 720                 .data           = &printk_ratelimit_state.burst,
 721                 .maxlen         = sizeof(int),
 722                 .mode           = 0644,
 723                 .proc_handler   = &proc_dointvec,
 724         },
 725 #endif
 726         {
 727                 .ctl_name       = KERN_NGROUPS_MAX,
 728                 .procname       = "ngroups_max",
 729                 .data           = &ngroups_max,
 730                 .maxlen         = sizeof (int),
 731                 .mode           = 0444,
 732                 .proc_handler   = &proc_dointvec,
 733         },
 734 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 735         {
 736                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 737                 .procname       = "unknown_nmi_panic",
 738                 .data           = &unknown_nmi_panic,
 739                 .maxlen         = sizeof (int),
 740                 .mode           = 0644,
 741                 .proc_handler   = &proc_dointvec,
 742         },
 743         {
 744                 .procname       = "nmi_watchdog",
 745                 .data           = &nmi_watchdog_enabled,
 746                 .maxlen         = sizeof (int),
 747                 .mode           = 0644,
 748                 .proc_handler   = &proc_nmi_enabled,
 749         },
 750 #endif
 751 #if defined(CONFIG_X86)
 752         {
 753                 .ctl_name       = KERN_PANIC_ON_NMI,
 754                 .procname       = "panic_on_unrecovered_nmi",
 755                 .data           = &panic_on_unrecovered_nmi,
 756                 .maxlen         = sizeof(int),
 757                 .mode           = 0644,
 758                 .proc_handler   = &proc_dointvec,
 759         },
 760         {
 761                 .ctl_name       = CTL_UNNUMBERED,
 762                 .procname       = "panic_on_io_nmi",
 763                 .data           = &panic_on_io_nmi,
 764                 .maxlen         = sizeof(int),
 765                 .mode           = 0644,
 766                 .proc_handler   = &proc_dointvec,
 767         },
 768         {
 769                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 770                 .procname       = "bootloader_type",
 771                 .data           = &bootloader_type,
 772                 .maxlen         = sizeof (int),
 773                 .mode           = 0444,
 774                 .proc_handler   = &proc_dointvec,
 775         },
 776         {
 777                 .ctl_name       = CTL_UNNUMBERED,
 778                 .procname       = "bootloader_version",
 779                 .data           = &bootloader_version,
 780                 .maxlen         = sizeof (int),
 781                 .mode           = 0444,
 782                 .proc_handler   = &proc_dointvec,
 783         },
 784         {
 785                 .ctl_name       = CTL_UNNUMBERED,
 786                 .procname       = "kstack_depth_to_print",
 787                 .data           = &kstack_depth_to_print,
 788                 .maxlen         = sizeof(int),
 789                 .mode           = 0644,
 790                 .proc_handler   = &proc_dointvec,
 791         },
 792         {
 793                 .ctl_name       = CTL_UNNUMBERED,
 794                 .procname       = "io_delay_type",
 795                 .data           = &io_delay_type,
 796                 .maxlen         = sizeof(int),
 797                 .mode           = 0644,
 798                 .proc_handler   = &proc_dointvec,
 799         },
 800 #endif
 801 #if defined(CONFIG_MMU)
 802         {
 803                 .ctl_name       = KERN_RANDOMIZE,
 804                 .procname       = "randomize_va_space",
 805                 .data           = &randomize_va_space,
 806                 .maxlen         = sizeof(int),
 807                 .mode           = 0644,
 808                 .proc_handler   = &proc_dointvec,
 809         },
 810 #endif
 811 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 812         {
 813                 .ctl_name       = KERN_SPIN_RETRY,
 814                 .procname       = "spin_retry",
 815                 .data           = &spin_retry,
 816                 .maxlen         = sizeof (int),
 817                 .mode           = 0644,
 818                 .proc_handler   = &proc_dointvec,
 819         },
 820 #endif
 821 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
 822         {
 823                 .procname       = "acpi_video_flags",
 824                 .data           = &acpi_realmode_flags,
 825                 .maxlen         = sizeof (unsigned long),
 826                 .mode           = 0644,
 827                 .proc_handler   = &proc_doulongvec_minmax,
 828         },
 829 #endif
 830 #ifdef CONFIG_IA64
 831         {
 832                 .ctl_name       = KERN_IA64_UNALIGNED,
 833                 .procname       = "ignore-unaligned-usertrap",
 834                 .data           = &no_unaligned_warning,
 835                 .maxlen         = sizeof (int),
 836                 .mode           = 0644,
 837                 .proc_handler   = &proc_dointvec,
 838         },
 839         {
 840                 .ctl_name       = CTL_UNNUMBERED,
 841                 .procname       = "unaligned-dump-stack",
 842                 .data           = &unaligned_dump_stack,
 843                 .maxlen         = sizeof (int),
 844                 .mode           = 0644,
 845                 .proc_handler   = &proc_dointvec,
 846         },
 847 #endif
 848 #ifdef CONFIG_DETECT_SOFTLOCKUP
 849         {
 850                 .ctl_name       = CTL_UNNUMBERED,
 851                 .procname       = "softlockup_panic",
 852                 .data           = &softlockup_panic,
 853                 .maxlen         = sizeof(int),
 854                 .mode           = 0644,
 855                 .proc_handler   = &proc_dointvec_minmax,
 856                 .strategy       = &sysctl_intvec,
 857                 .extra1         = &zero,
 858                 .extra2         = &one,
 859         },
 860         {
 861                 .ctl_name       = CTL_UNNUMBERED,
 862                 .procname       = "softlockup_thresh",
 863                 .data           = &softlockup_thresh,
 864                 .maxlen         = sizeof(int),
 865                 .mode           = 0644,
 866                 .proc_handler   = &proc_dosoftlockup_thresh,
 867                 .strategy       = &sysctl_intvec,
 868                 .extra1         = &neg_one,
 869                 .extra2         = &sixty,
 870         },
 871 #endif
 872 #ifdef CONFIG_DETECT_HUNG_TASK
 873         {
 874                 .ctl_name       = CTL_UNNUMBERED,
 875                 .procname       = "hung_task_panic",
 876                 .data           = &sysctl_hung_task_panic,
 877                 .maxlen         = sizeof(int),
 878                 .mode           = 0644,
 879                 .proc_handler   = &proc_dointvec_minmax,
 880                 .strategy       = &sysctl_intvec,
 881                 .extra1         = &zero,
 882                 .extra2         = &one,
 883         },
 884         {
 885                 .ctl_name       = CTL_UNNUMBERED,
 886                 .procname       = "hung_task_check_count",
 887                 .data           = &sysctl_hung_task_check_count,
 888                 .maxlen         = sizeof(unsigned long),
 889                 .mode           = 0644,
 890                 .proc_handler   = &proc_doulongvec_minmax,
 891                 .strategy       = &sysctl_intvec,
 892         },
 893         {
 894                 .ctl_name       = CTL_UNNUMBERED,
 895                 .procname       = "hung_task_timeout_secs",
 896                 .data           = &sysctl_hung_task_timeout_secs,
 897                 .maxlen         = sizeof(unsigned long),
 898                 .mode           = 0644,
 899                 .proc_handler   = &proc_dohung_task_timeout_secs,
 900                 .strategy       = &sysctl_intvec,
 901         },
 902         {
 903                 .ctl_name       = CTL_UNNUMBERED,
 904                 .procname       = "hung_task_warnings",
 905                 .data           = &sysctl_hung_task_warnings,
 906                 .maxlen         = sizeof(unsigned long),
 907                 .mode           = 0644,
 908                 .proc_handler   = &proc_doulongvec_minmax,
 909                 .strategy       = &sysctl_intvec,
 910         },
 911 #endif
 912 #ifdef CONFIG_COMPAT
 913         {
 914                 .ctl_name       = KERN_COMPAT_LOG,
 915                 .procname       = "compat-log",
 916                 .data           = &compat_log,
 917                 .maxlen         = sizeof (int),
 918                 .mode           = 0644,
 919                 .proc_handler   = &proc_dointvec,
 920         },
 921 #endif
 922 #ifdef CONFIG_RT_MUTEXES
 923         {
 924                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 925                 .procname       = "max_lock_depth",
 926                 .data           = &max_lock_depth,
 927                 .maxlen         = sizeof(int),
 928                 .mode           = 0644,
 929                 .proc_handler   = &proc_dointvec,
 930         },
 931 #endif
 932         {
 933                 .ctl_name       = CTL_UNNUMBERED,
 934                 .procname       = "poweroff_cmd",
 935                 .data           = &poweroff_cmd,
 936                 .maxlen         = POWEROFF_CMD_PATH_LEN,
 937                 .mode           = 0644,
 938                 .proc_handler   = &proc_dostring,
 939                 .strategy       = &sysctl_string,
 940         },
 941 #ifdef CONFIG_KEYS
 942         {
 943                 .ctl_name       = CTL_UNNUMBERED,
 944                 .procname       = "keys",
 945                 .mode           = 0555,
 946                 .child          = key_sysctls,
 947         },
 948 #endif
 949 #ifdef CONFIG_RCU_TORTURE_TEST
 950         {
 951                 .ctl_name       = CTL_UNNUMBERED,
 952                 .procname       = "rcutorture_runnable",
 953                 .data           = &rcutorture_runnable,
 954                 .maxlen         = sizeof(int),
 955                 .mode           = 0644,
 956                 .proc_handler   = &proc_dointvec,
 957         },
 958 #endif
 959 #ifdef CONFIG_SLOW_WORK
 960         {
 961                 .ctl_name       = CTL_UNNUMBERED,
 962                 .procname       = "slow-work",
 963                 .mode           = 0555,
 964                 .child          = slow_work_sysctls,
 965         },
 966 #endif
 967 #ifdef CONFIG_PERF_COUNTERS
 968         {
 969                 .ctl_name       = CTL_UNNUMBERED,
 970                 .procname       = "perf_counter_paranoid",
 971                 .data           = &sysctl_perf_counter_paranoid,
 972                 .maxlen         = sizeof(sysctl_perf_counter_paranoid),
 973                 .mode           = 0644,
 974                 .proc_handler   = &proc_dointvec,
 975         },
 976         {
 977                 .ctl_name       = CTL_UNNUMBERED,
 978                 .procname       = "perf_counter_mlock_kb",
 979                 .data           = &sysctl_perf_counter_mlock,
 980                 .maxlen         = sizeof(sysctl_perf_counter_mlock),
 981                 .mode           = 0644,
 982                 .proc_handler   = &proc_dointvec,
 983         },
 984         {
 985                 .ctl_name       = CTL_UNNUMBERED,
 986                 .procname       = "perf_counter_max_sample_rate",
 987                 .data           = &sysctl_perf_counter_sample_rate,
 988                 .maxlen         = sizeof(sysctl_perf_counter_sample_rate),
 989                 .mode           = 0644,
 990                 .proc_handler   = &proc_dointvec,
 991         },
 992 #endif
 993 #ifdef CONFIG_KMEMCHECK
 994         {
 995                 .ctl_name       = CTL_UNNUMBERED,
 996                 .procname       = "kmemcheck",
 997                 .data           = &kmemcheck_enabled,
 998                 .maxlen         = sizeof(int),
 999                 .mode           = 0644,
1000                 .proc_handler   = &proc_dointvec,
1001         },
1002 #endif
1003 #ifdef CONFIG_BLOCK
1004         {
1005                 .ctl_name       = CTL_UNNUMBERED,
1006                 .procname       = "blk_iopoll",
1007                 .data           = &blk_iopoll_enabled,
1008                 .maxlen         = sizeof(int),
1009                 .mode           = 0644,
1010                 .proc_handler   = &proc_dointvec,
1011         },
1012 #endif
1013 /*
1014  * NOTE: do not add new entries to this table unless you have read
1015  * Documentation/sysctl/ctl_unnumbered.txt
1016  */
1017         { .ctl_name = 0 }
1018 };
1019
1020 static struct ctl_table vm_table[] = {
1021         {
1022                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
1023                 .procname       = "overcommit_memory",
1024                 .data           = &sysctl_overcommit_memory,
1025                 .maxlen         = sizeof(sysctl_overcommit_memory),
1026                 .mode           = 0644,
1027                 .proc_handler   = &proc_dointvec,
1028         },
1029         {
1030                 .ctl_name       = VM_PANIC_ON_OOM,
1031                 .procname       = "panic_on_oom",
1032                 .data           = &sysctl_panic_on_oom,
1033                 .maxlen         = sizeof(sysctl_panic_on_oom),
1034                 .mode           = 0644,
1035                 .proc_handler   = &proc_dointvec,
1036         },
1037         {
1038                 .ctl_name       = CTL_UNNUMBERED,
1039                 .procname       = "oom_kill_allocating_task",
1040                 .data           = &sysctl_oom_kill_allocating_task,
1041                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
1042                 .mode           = 0644,
1043                 .proc_handler   = &proc_dointvec,
1044         },
1045         {
1046                 .ctl_name       = CTL_UNNUMBERED,
1047                 .procname       = "oom_dump_tasks",
1048                 .data           = &sysctl_oom_dump_tasks,
1049                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
1050                 .mode           = 0644,
1051                 .proc_handler   = &proc_dointvec,
1052         },
1053         {
1054                 .ctl_name       = VM_OVERCOMMIT_RATIO,
1055                 .procname       = "overcommit_ratio",
1056                 .data           = &sysctl_overcommit_ratio,
1057                 .maxlen         = sizeof(sysctl_overcommit_ratio),
1058                 .mode           = 0644,
1059                 .proc_handler   = &proc_dointvec,
1060         },
1061         {
1062                 .ctl_name       = VM_PAGE_CLUSTER,
1063                 .procname       = "page-cluster",
1064                 .data           = &page_cluster,
1065                 .maxlen         = sizeof(int),
1066                 .mode           = 0644,
1067                 .proc_handler   = &proc_dointvec,
1068         },
1069         {
1070                 .ctl_name       = VM_DIRTY_BACKGROUND,
1071                 .procname       = "dirty_background_ratio",
1072                 .data           = &dirty_background_ratio,
1073                 .maxlen         = sizeof(dirty_background_ratio),
1074                 .mode           = 0644,
1075                 .proc_handler   = &dirty_background_ratio_handler,
1076                 .strategy       = &sysctl_intvec,
1077                 .extra1         = &zero,
1078                 .extra2         = &one_hundred,
1079         },
1080         {
1081                 .ctl_name       = CTL_UNNUMBERED,
1082                 .procname       = "dirty_background_bytes",
1083                 .data           = &dirty_background_bytes,
1084                 .maxlen         = sizeof(dirty_background_bytes),
1085                 .mode           = 0644,
1086                 .proc_handler   = &dirty_background_bytes_handler,
1087                 .strategy       = &sysctl_intvec,
1088                 .extra1         = &one_ul,
1089         },
1090         {
1091                 .ctl_name       = VM_DIRTY_RATIO,
1092                 .procname       = "dirty_ratio",
1093                 .data           = &vm_dirty_ratio,
1094                 .maxlen         = sizeof(vm_dirty_ratio),
1095                 .mode           = 0644,
1096                 .proc_handler   = &dirty_ratio_handler,
1097                 .strategy       = &sysctl_intvec,
1098                 .extra1         = &zero,
1099                 .extra2         = &one_hundred,
1100         },
1101         {
1102                 .ctl_name       = CTL_UNNUMBERED,
1103                 .procname       = "dirty_bytes",
1104                 .data           = &vm_dirty_bytes,
1105                 .maxlen         = sizeof(vm_dirty_bytes),
1106                 .mode           = 0644,
1107                 .proc_handler   = &dirty_bytes_handler,
1108                 .strategy       = &sysctl_intvec,
1109                 .extra1         = &dirty_bytes_min,
1110         },
1111         {
1112                 .procname       = "dirty_writeback_centisecs",
1113                 .data           = &dirty_writeback_interval,
1114                 .maxlen         = sizeof(dirty_writeback_interval),
1115                 .mode           = 0644,
1116                 .proc_handler   = &dirty_writeback_centisecs_handler,
1117         },
1118         {
1119                 .procname       = "dirty_expire_centisecs",
1120                 .data           = &dirty_expire_interval,
1121                 .maxlen         = sizeof(dirty_expire_interval),
1122                 .mode           = 0644,
1123                 .proc_handler   = &proc_dointvec,
1124         },
1125         {
1126                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
1127                 .procname       = "nr_pdflush_threads",
1128                 .data           = &nr_pdflush_threads,
1129                 .maxlen         = sizeof nr_pdflush_threads,
1130                 .mode           = 0444 /* read-only*/,
1131                 .proc_handler   = &proc_dointvec,
1132         },
1133         {
1134                 .ctl_name       = VM_SWAPPINESS,
1135                 .procname       = "swappiness",
1136                 .data           = &vm_swappiness,
1137                 .maxlen         = sizeof(vm_swappiness),
1138                 .mode           = 0644,
1139                 .proc_handler   = &proc_dointvec_minmax,
1140                 .strategy       = &sysctl_intvec,
1141                 .extra1         = &zero,
1142                 .extra2         = &one_hundred,
1143         },
1144 #ifdef CONFIG_HUGETLB_PAGE
1145          {
1146                 .procname       = "nr_hugepages",
1147                 .data           = NULL,
1148                 .maxlen         = sizeof(unsigned long),
1149                 .mode           = 0644,
1150                 .proc_handler   = &hugetlb_sysctl_handler,
1151                 .extra1         = (void *)&hugetlb_zero,
1152                 .extra2         = (void *)&hugetlb_infinity,
1153          },
1154          {
1155                 .ctl_name       = VM_HUGETLB_GROUP,
1156                 .procname       = "hugetlb_shm_group",
1157                 .data           = &sysctl_hugetlb_shm_group,
1158                 .maxlen         = sizeof(gid_t),
1159                 .mode           = 0644,
1160                 .proc_handler   = &proc_dointvec,
1161          },
1162          {
1163                 .ctl_name       = CTL_UNNUMBERED,
1164                 .procname       = "hugepages_treat_as_movable",
1165                 .data           = &hugepages_treat_as_movable,
1166                 .maxlen         = sizeof(int),
1167                 .mode           = 0644,
1168                 .proc_handler   = &hugetlb_treat_movable_handler,
1169         },
1170         {
1171                 .ctl_name       = CTL_UNNUMBERED,
1172                 .procname       = "nr_overcommit_hugepages",
1173                 .data           = NULL,
1174                 .maxlen         = sizeof(unsigned long),
1175                 .mode           = 0644,
1176                 .proc_handler   = &hugetlb_overcommit_handler,
1177                 .extra1         = (void *)&hugetlb_zero,
1178                 .extra2         = (void *)&hugetlb_infinity,
1179         },
1180 #endif
1181         {
1182                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
1183                 .procname       = "lowmem_reserve_ratio",
1184                 .data           = &sysctl_lowmem_reserve_ratio,
1185                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1186                 .mode           = 0644,
1187                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
1188                 .strategy       = &sysctl_intvec,
1189         },
1190         {
1191                 .ctl_name       = VM_DROP_PAGECACHE,
1192                 .procname       = "drop_caches",
1193                 .data           = &sysctl_drop_caches,
1194                 .maxlen         = sizeof(int),
1195                 .mode           = 0644,
1196                 .proc_handler   = drop_caches_sysctl_handler,
1197                 .strategy       = &sysctl_intvec,
1198         },
1199         {
1200                 .ctl_name       = VM_MIN_FREE_KBYTES,
1201                 .procname       = "min_free_kbytes",
1202                 .data           = &min_free_kbytes,
1203                 .maxlen         = sizeof(min_free_kbytes),
1204                 .mode           = 0644,
1205                 .proc_handler   = &min_free_kbytes_sysctl_handler,
1206                 .strategy       = &sysctl_intvec,
1207                 .extra1         = &zero,
1208         },
1209         {
1210                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
1211                 .procname       = "percpu_pagelist_fraction",
1212                 .data           = &percpu_pagelist_fraction,
1213                 .maxlen         = sizeof(percpu_pagelist_fraction),
1214                 .mode           = 0644,
1215                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
1216                 .strategy       = &sysctl_intvec,
1217                 .extra1         = &min_percpu_pagelist_fract,
1218         },
1219 #ifdef CONFIG_MMU
1220         {
1221                 .ctl_name       = VM_MAX_MAP_COUNT,
1222                 .procname       = "max_map_count",
1223                 .data           = &sysctl_max_map_count,
1224                 .maxlen         = sizeof(sysctl_max_map_count),
1225                 .mode           = 0644,
1226                 .proc_handler   = &proc_dointvec
1227         },
1228 #else
1229         {
1230                 .ctl_name       = CTL_UNNUMBERED,
1231                 .procname       = "nr_trim_pages",
1232                 .data           = &sysctl_nr_trim_pages,
1233                 .maxlen         = sizeof(sysctl_nr_trim_pages),
1234                 .mode           = 0644,
1235                 .proc_handler   = &proc_dointvec_minmax,
1236                 .strategy       = &sysctl_intvec,
1237                 .extra1         = &zero,
1238         },
1239 #endif
1240         {
1241                 .ctl_name       = VM_LAPTOP_MODE,
1242                 .procname       = "laptop_mode",
1243                 .data           = &laptop_mode,
1244                 .maxlen         = sizeof(laptop_mode),
1245                 .mode           = 0644,
1246                 .proc_handler   = &proc_dointvec_jiffies,
1247                 .strategy       = &sysctl_jiffies,
1248         },
1249         {
1250                 .ctl_name       = VM_BLOCK_DUMP,
1251                 .procname       = "block_dump",
1252                 .data           = &block_dump,
1253                 .maxlen         = sizeof(block_dump),
1254                 .mode           = 0644,
1255                 .proc_handler   = &proc_dointvec,
1256                 .strategy       = &sysctl_intvec,
1257                 .extra1         = &zero,
1258         },
1259         {
1260                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
1261                 .procname       = "vfs_cache_pressure",
1262                 .data           = &sysctl_vfs_cache_pressure,
1263                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1264                 .mode           = 0644,
1265                 .proc_handler   = &proc_dointvec,
1266                 .strategy       = &sysctl_intvec,
1267                 .extra1         = &zero,
1268         },
1269 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1270         {
1271                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
1272                 .procname       = "legacy_va_layout",
1273                 .data           = &sysctl_legacy_va_layout,
1274                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1275                 .mode           = 0644,
1276                 .proc_handler   = &proc_dointvec,
1277                 .strategy       = &sysctl_intvec,
1278                 .extra1         = &zero,
1279         },
1280 #endif
1281 #ifdef CONFIG_NUMA
1282         {
1283                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
1284                 .procname       = "zone_reclaim_mode",
1285                 .data           = &zone_reclaim_mode,
1286                 .maxlen         = sizeof(zone_reclaim_mode),
1287                 .mode           = 0644,
1288                 .proc_handler   = &proc_dointvec,
1289                 .strategy       = &sysctl_intvec,
1290                 .extra1         = &zero,
1291         },
1292         {
1293                 .ctl_name       = VM_MIN_UNMAPPED,
1294                 .procname       = "min_unmapped_ratio",
1295                 .data           = &sysctl_min_unmapped_ratio,
1296                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1297                 .mode           = 0644,
1298                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1299                 .strategy       = &sysctl_intvec,
1300                 .extra1         = &zero,
1301                 .extra2         = &one_hundred,
1302         },
1303         {
1304                 .ctl_name       = VM_MIN_SLAB,
1305                 .procname       = "min_slab_ratio",
1306                 .data           = &sysctl_min_slab_ratio,
1307                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1308                 .mode           = 0644,
1309                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1310                 .strategy       = &sysctl_intvec,
1311                 .extra1         = &zero,
1312                 .extra2         = &one_hundred,
1313         },
1314 #endif
1315 #ifdef CONFIG_SMP
1316         {
1317                 .ctl_name       = CTL_UNNUMBERED,
1318                 .procname       = "stat_interval",
1319                 .data           = &sysctl_stat_interval,
1320                 .maxlen         = sizeof(sysctl_stat_interval),
1321                 .mode           = 0644,
1322                 .proc_handler   = &proc_dointvec_jiffies,
1323                 .strategy       = &sysctl_jiffies,
1324         },
1325 #endif
1326         {
1327                 .ctl_name       = CTL_UNNUMBERED,
1328                 .procname       = "mmap_min_addr",
1329                 .data           = &dac_mmap_min_addr,
1330                 .maxlen         = sizeof(unsigned long),
1331                 .mode           = 0644,
1332                 .proc_handler   = &mmap_min_addr_handler,
1333         },
1334 #ifdef CONFIG_NUMA
1335         {
1336                 .ctl_name       = CTL_UNNUMBERED,
1337                 .procname       = "numa_zonelist_order",
1338                 .data           = &numa_zonelist_order,
1339                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1340                 .mode           = 0644,
1341                 .proc_handler   = &numa_zonelist_order_handler,
1342                 .strategy       = &sysctl_string,
1343         },
1344 #endif
1345 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1346    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1347         {
1348                 .ctl_name       = VM_VDSO_ENABLED,
1349                 .procname       = "vdso_enabled",
1350                 .data           = &vdso_enabled,
1351                 .maxlen         = sizeof(vdso_enabled),
1352                 .mode           = 0644,
1353                 .proc_handler   = &proc_dointvec,
1354                 .strategy       = &sysctl_intvec,
1355                 .extra1         = &zero,
1356         },
1357 #endif
1358 #ifdef CONFIG_HIGHMEM
1359         {
1360                 .ctl_name       = CTL_UNNUMBERED,
1361                 .procname       = "highmem_is_dirtyable",
1362                 .data           = &vm_highmem_is_dirtyable,
1363                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1364                 .mode           = 0644,
1365                 .proc_handler   = &proc_dointvec_minmax,
1366                 .strategy       = &sysctl_intvec,
1367                 .extra1         = &zero,
1368                 .extra2         = &one,
1369         },
1370 #endif
1371         {
1372                 .ctl_name       = CTL_UNNUMBERED,
1373                 .procname       = "scan_unevictable_pages",
1374                 .data           = &scan_unevictable_pages,
1375                 .maxlen         = sizeof(scan_unevictable_pages),
1376                 .mode           = 0644,
1377                 .proc_handler   = &scan_unevictable_handler,
1378         },
1379 /*
1380  * NOTE: do not add new entries to this table unless you have read
1381  * Documentation/sysctl/ctl_unnumbered.txt
1382  */
1383         { .ctl_name = 0 }
1384 };
1385
1386 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1387 static struct ctl_table binfmt_misc_table[] = {
1388         { .ctl_name = 0 }
1389 };
1390 #endif
1391
1392 static struct ctl_table fs_table[] = {
1393         {
1394                 .ctl_name       = FS_NRINODE,
1395                 .procname       = "inode-nr",
1396                 .data           = &inodes_stat,
1397                 .maxlen         = 2*sizeof(int),
1398                 .mode           = 0444,
1399                 .proc_handler   = &proc_dointvec,
1400         },
1401         {
1402                 .ctl_name       = FS_STATINODE,
1403                 .procname       = "inode-state",
1404                 .data           = &inodes_stat,
1405                 .maxlen         = 7*sizeof(int),
1406                 .mode           = 0444,
1407                 .proc_handler   = &proc_dointvec,
1408         },
1409         {
1410                 .procname       = "file-nr",
1411                 .data           = &files_stat,
1412                 .maxlen         = 3*sizeof(int),
1413                 .mode           = 0444,
1414                 .proc_handler   = &proc_nr_files,
1415         },
1416         {
1417                 .ctl_name       = FS_MAXFILE,
1418                 .procname       = "file-max",
1419                 .data           = &files_stat.max_files,
1420                 .maxlen         = sizeof(int),
1421                 .mode           = 0644,
1422                 .proc_handler   = &proc_dointvec,
1423         },
1424         {
1425                 .ctl_name       = CTL_UNNUMBERED,
1426                 .procname       = "nr_open",
1427                 .data           = &sysctl_nr_open,
1428                 .maxlen         = sizeof(int),
1429                 .mode           = 0644,
1430                 .proc_handler   = &proc_dointvec_minmax,
1431                 .extra1         = &sysctl_nr_open_min,
1432                 .extra2         = &sysctl_nr_open_max,
1433         },
1434         {
1435                 .ctl_name       = FS_DENTRY,
1436                 .procname       = "dentry-state",
1437                 .data           = &dentry_stat,
1438                 .maxlen         = 6*sizeof(int),
1439                 .mode           = 0444,
1440                 .proc_handler   = &proc_dointvec,
1441         },
1442         {
1443                 .ctl_name       = FS_OVERFLOWUID,
1444                 .procname       = "overflowuid",
1445                 .data           = &fs_overflowuid,
1446                 .maxlen         = sizeof(int),
1447                 .mode           = 0644,
1448                 .proc_handler   = &proc_dointvec_minmax,
1449                 .strategy       = &sysctl_intvec,
1450                 .extra1         = &minolduid,
1451                 .extra2         = &maxolduid,
1452         },
1453         {
1454                 .ctl_name       = FS_OVERFLOWGID,
1455                 .procname       = "overflowgid",
1456                 .data           = &fs_overflowgid,
1457                 .maxlen         = sizeof(int),
1458                 .mode           = 0644,
1459                 .proc_handler   = &proc_dointvec_minmax,
1460                 .strategy       = &sysctl_intvec,
1461                 .extra1         = &minolduid,
1462                 .extra2         = &maxolduid,
1463         },
1464 #ifdef CONFIG_FILE_LOCKING
1465         {
1466                 .ctl_name       = FS_LEASES,
1467                 .procname       = "leases-enable",
1468                 .data           = &leases_enable,
1469                 .maxlen         = sizeof(int),
1470                 .mode           = 0644,
1471                 .proc_handler   = &proc_dointvec,
1472         },
1473 #endif
1474 #ifdef CONFIG_DNOTIFY
1475         {
1476                 .ctl_name       = FS_DIR_NOTIFY,
1477                 .procname       = "dir-notify-enable",
1478                 .data           = &dir_notify_enable,
1479                 .maxlen         = sizeof(int),
1480                 .mode           = 0644,
1481                 .proc_handler   = &proc_dointvec,
1482         },
1483 #endif
1484 #ifdef CONFIG_MMU
1485 #ifdef CONFIG_FILE_LOCKING
1486         {
1487                 .ctl_name       = FS_LEASE_TIME,
1488                 .procname       = "lease-break-time",
1489                 .data           = &lease_break_time,
1490                 .maxlen         = sizeof(int),
1491                 .mode           = 0644,
1492                 .proc_handler   = &proc_dointvec,
1493         },
1494 #endif
1495 #ifdef CONFIG_AIO
1496         {
1497                 .procname       = "aio-nr",
1498                 .data           = &aio_nr,
1499                 .maxlen         = sizeof(aio_nr),
1500                 .mode           = 0444,
1501                 .proc_handler   = &proc_doulongvec_minmax,
1502         },
1503         {
1504                 .procname       = "aio-max-nr",
1505                 .data           = &aio_max_nr,
1506                 .maxlen         = sizeof(aio_max_nr),
1507                 .mode           = 0644,
1508                 .proc_handler   = &proc_doulongvec_minmax,
1509         },
1510 #endif /* CONFIG_AIO */
1511 #ifdef CONFIG_INOTIFY_USER
1512         {
1513                 .ctl_name       = FS_INOTIFY,
1514                 .procname       = "inotify",
1515                 .mode           = 0555,
1516                 .child          = inotify_table,
1517         },
1518 #endif
1519 #ifdef CONFIG_EPOLL
1520         {
1521                 .procname       = "epoll",
1522                 .mode           = 0555,
1523                 .child          = epoll_table,
1524         },
1525 #endif
1526 #endif
1527         {
1528                 .ctl_name       = KERN_SETUID_DUMPABLE,
1529                 .procname       = "suid_dumpable",
1530                 .data           = &suid_dumpable,
1531                 .maxlen         = sizeof(int),
1532                 .mode           = 0644,
1533                 .proc_handler   = &proc_dointvec_minmax,
1534                 .strategy       = &sysctl_intvec,
1535                 .extra1         = &zero,
1536                 .extra2         = &two,
1537         },
1538 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1539         {
1540                 .ctl_name       = CTL_UNNUMBERED,
1541                 .procname       = "binfmt_misc",
1542                 .mode           = 0555,
1543                 .child          = binfmt_misc_table,
1544         },
1545 #endif
1546 /*
1547  * NOTE: do not add new entries to this table unless you have read
1548  * Documentation/sysctl/ctl_unnumbered.txt
1549  */
1550         { .ctl_name = 0 }
1551 };
1552
1553 static struct ctl_table debug_table[] = {
1554 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1555         {
1556                 .ctl_name       = CTL_UNNUMBERED,
1557                 .procname       = "exception-trace",
1558                 .data           = &show_unhandled_signals,
1559                 .maxlen         = sizeof(int),
1560                 .mode           = 0644,
1561                 .proc_handler   = proc_dointvec
1562         },
1563 #endif
1564         { .ctl_name = 0 }
1565 };
1566
1567 static struct ctl_table dev_table[] = {
1568         { .ctl_name = 0 }
1569 };
1570
1571 static DEFINE_SPINLOCK(sysctl_lock);
1572
1573 /* called under sysctl_lock */
1574 static int use_table(struct ctl_table_header *p)
1575 {
1576         if (unlikely(p->unregistering))
1577                 return 0;
1578         p->used++;
1579         return 1;
1580 }
1581
1582 /* called under sysctl_lock */
1583 static void unuse_table(struct ctl_table_header *p)
1584 {
1585         if (!--p->used)
1586                 if (unlikely(p->unregistering))
1587                         complete(p->unregistering);
1588 }
1589
1590 /* called under sysctl_lock, will reacquire if has to wait */
1591 static void start_unregistering(struct ctl_table_header *p)
1592 {
1593         /*
1594          * if p->used is 0, nobody will ever touch that entry again;
1595          * we'll eliminate all paths to it before dropping sysctl_lock
1596          */
1597         if (unlikely(p->used)) {
1598                 struct completion wait;
1599                 init_completion(&wait);
1600                 p->unregistering = &wait;
1601                 spin_unlock(&sysctl_lock);
1602                 wait_for_completion(&wait);
1603                 spin_lock(&sysctl_lock);
1604         } else {
1605                 /* anything non-NULL; we'll never dereference it */
1606                 p->unregistering = ERR_PTR(-EINVAL);
1607         }
1608         /*
1609          * do not remove from the list until nobody holds it; walking the
1610          * list in do_sysctl() relies on that.
1611          */
1612         list_del_init(&p->ctl_entry);
1613 }
1614
1615 void sysctl_head_get(struct ctl_table_header *head)
1616 {
1617         spin_lock(&sysctl_lock);
1618         head->count++;
1619         spin_unlock(&sysctl_lock);
1620 }
1621
1622 void sysctl_head_put(struct ctl_table_header *head)
1623 {
1624         spin_lock(&sysctl_lock);
1625         if (!--head->count)
1626                 kfree(head);
1627         spin_unlock(&sysctl_lock);
1628 }
1629
1630 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1631 {
1632         if (!head)
1633                 BUG();
1634         spin_lock(&sysctl_lock);
1635         if (!use_table(head))
1636                 head = ERR_PTR(-ENOENT);
1637         spin_unlock(&sysctl_lock);
1638         return head;
1639 }
1640
1641 void sysctl_head_finish(struct ctl_table_header *head)
1642 {
1643         if (!head)
1644                 return;
1645         spin_lock(&sysctl_lock);
1646         unuse_table(head);
1647         spin_unlock(&sysctl_lock);
1648 }
1649
1650 static struct ctl_table_set *
1651 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1652 {
1653         struct ctl_table_set *set = &root->default_set;
1654         if (root->lookup)
1655                 set = root->lookup(root, namespaces);
1656         return set;
1657 }
1658
1659 static struct list_head *
1660 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1661 {
1662         struct ctl_table_set *set = lookup_header_set(root, namespaces);
1663         return &set->list;
1664 }
1665
1666 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1667                                             struct ctl_table_header *prev)
1668 {
1669         struct ctl_table_root *root;
1670         struct list_head *header_list;
1671         struct ctl_table_header *head;
1672         struct list_head *tmp;
1673
1674         spin_lock(&sysctl_lock);
1675         if (prev) {
1676                 head = prev;
1677                 tmp = &prev->ctl_entry;
1678                 unuse_table(prev);
1679                 goto next;
1680         }
1681         tmp = &root_table_header.ctl_entry;
1682         for (;;) {
1683                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1684
1685                 if (!use_table(head))
1686                         goto next;
1687                 spin_unlock(&sysctl_lock);
1688                 return head;
1689         next:
1690                 root = head->root;
1691                 tmp = tmp->next;
1692                 header_list = lookup_header_list(root, namespaces);
1693                 if (tmp != header_list)
1694                         continue;
1695
1696                 do {
1697                         root = list_entry(root->root_list.next,
1698                                         struct ctl_table_root, root_list);
1699                         if (root == &sysctl_table_root)
1700                                 goto out;
1701                         header_list = lookup_header_list(root, namespaces);
1702                 } while (list_empty(header_list));
1703                 tmp = header_list->next;
1704         }
1705 out:
1706         spin_unlock(&sysctl_lock);
1707         return NULL;
1708 }
1709
1710 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1711 {
1712         return __sysctl_head_next(current->nsproxy, prev);
1713 }
1714
1715 void register_sysctl_root(struct ctl_table_root *root)
1716 {
1717         spin_lock(&sysctl_lock);
1718         list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1719         spin_unlock(&sysctl_lock);
1720 }
1721
1722 #ifdef CONFIG_SYSCTL_SYSCALL
1723 /* Perform the actual read/write of a sysctl table entry. */
1724 static int do_sysctl_strategy(struct ctl_table_root *root,
1725                         struct ctl_table *table,
1726                         void __user *oldval, size_t __user *oldlenp,
1727                         void __user *newval, size_t newlen)
1728 {
1729         int op = 0, rc;
1730
1731         if (oldval)
1732                 op |= MAY_READ;
1733         if (newval)
1734                 op |= MAY_WRITE;
1735         if (sysctl_perm(root, table, op))
1736                 return -EPERM;
1737
1738         if (table->strategy) {
1739                 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1740                 if (rc < 0)
1741                         return rc;
1742                 if (rc > 0)
1743                         return 0;
1744         }
1745
1746         /* If there is no strategy routine, or if the strategy returns
1747          * zero, proceed with automatic r/w */
1748         if (table->data && table->maxlen) {
1749                 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1750                 if (rc < 0)
1751                         return rc;
1752         }
1753         return 0;
1754 }
1755
1756 static int parse_table(int __user *name, int nlen,
1757                        void __user *oldval, size_t __user *oldlenp,
1758                        void __user *newval, size_t newlen,
1759                        struct ctl_table_root *root,
1760                        struct ctl_table *table)
1761 {
1762         int n;
1763 repeat:
1764         if (!nlen)
1765                 return -ENOTDIR;
1766         if (get_user(n, name))
1767                 return -EFAULT;
1768         for ( ; table->ctl_name || table->procname; table++) {
1769                 if (!table->ctl_name)
1770                         continue;
1771                 if (n == table->ctl_name) {
1772                         int error;
1773                         if (table->child) {
1774                                 if (sysctl_perm(root, table, MAY_EXEC))
1775                                         return -EPERM;
1776                                 name++;
1777                                 nlen--;
1778                                 table = table->child;
1779                                 goto repeat;
1780                         }
1781                         error = do_sysctl_strategy(root, table,
1782                                                    oldval, oldlenp,
1783                                                    newval, newlen);
1784                         return error;
1785                 }
1786         }
1787         return -ENOTDIR;
1788 }
1789
1790 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1791                void __user *newval, size_t newlen)
1792 {
1793         struct ctl_table_header *head;
1794         int error = -ENOTDIR;
1795
1796         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1797                 return -ENOTDIR;
1798         if (oldval) {
1799                 int old_len;
1800                 if (!oldlenp || get_user(old_len, oldlenp))
1801                         return -EFAULT;
1802         }
1803
1804         for (head = sysctl_head_next(NULL); head;
1805                         head = sysctl_head_next(head)) {
1806                 error = parse_table(name, nlen, oldval, oldlenp,
1807                                         newval, newlen,
1808                                         head->root, head->ctl_table);
1809                 if (error != -ENOTDIR) {
1810                         sysctl_head_finish(head);
1811                         break;
1812                 }
1813         }
1814         return error;
1815 }
1816
1817 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1818 {
1819         struct __sysctl_args tmp;
1820         int error;
1821
1822         if (copy_from_user(&tmp, args, sizeof(tmp)))
1823                 return -EFAULT;
1824
1825         error = deprecated_sysctl_warning(&tmp);
1826         if (error)
1827                 goto out;
1828
1829         lock_kernel();
1830         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1831                           tmp.newval, tmp.newlen);
1832         unlock_kernel();
1833 out:
1834         return error;
1835 }
1836 #endif /* CONFIG_SYSCTL_SYSCALL */
1837
1838 /*
1839  * sysctl_perm does NOT grant the superuser all rights automatically, because
1840  * some sysctl variables are readonly even to root.
1841  */
1842
1843 static int test_perm(int mode, int op)
1844 {
1845         if (!current_euid())
1846                 mode >>= 6;
1847         else if (in_egroup_p(0))
1848                 mode >>= 3;
1849         if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1850                 return 0;
1851         return -EACCES;
1852 }
1853
1854 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1855 {
1856         int error;
1857         int mode;
1858
1859         error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1860         if (error)
1861                 return error;
1862
1863         if (root->permissions)
1864                 mode = root->permissions(root, current->nsproxy, table);
1865         else
1866                 mode = table->mode;
1867
1868         return test_perm(mode, op);
1869 }
1870
1871 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1872 {
1873         for (; table->ctl_name || table->procname; table++) {
1874                 table->parent = parent;
1875                 if (table->child)
1876                         sysctl_set_parent(table, table->child);
1877         }
1878 }
1879
1880 static __init int sysctl_init(void)
1881 {
1882         sysctl_set_parent(NULL, root_table);
1883 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1884         {
1885                 int err;
1886                 err = sysctl_check_table(current->nsproxy, root_table);
1887         }
1888 #endif
1889         return 0;
1890 }
1891
1892 core_initcall(sysctl_init);
1893
1894 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1895                                       struct ctl_table *table)
1896 {
1897         struct ctl_table *p;
1898         const char *s = branch->procname;
1899
1900         /* branch should have named subdirectory as its first element */
1901         if (!s || !branch->child)
1902                 return NULL;
1903
1904         /* ... and nothing else */
1905         if (branch[1].procname || branch[1].ctl_name)
1906                 return NULL;
1907
1908         /* table should contain subdirectory with the same name */
1909         for (p = table; p->procname || p->ctl_name; p++) {
1910                 if (!p->child)
1911                         continue;
1912                 if (p->procname && strcmp(p->procname, s) == 0)
1913                         return p;
1914         }
1915         return NULL;
1916 }
1917
1918 /* see if attaching q to p would be an improvement */
1919 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1920 {
1921         struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1922         struct ctl_table *next;
1923         int is_better = 0;
1924         int not_in_parent = !p->attached_by;
1925
1926         while ((next = is_branch_in(by, to)) != NULL) {
1927                 if (by == q->attached_by)
1928                         is_better = 1;
1929                 if (to == p->attached_by)
1930                         not_in_parent = 1;
1931                 by = by->child;
1932                 to = next->child;
1933         }
1934
1935         if (is_better && not_in_parent) {
1936                 q->attached_by = by;
1937                 q->attached_to = to;
1938                 q->parent = p;
1939         }
1940 }
1941
1942 /**
1943  * __register_sysctl_paths - register a sysctl hierarchy
1944  * @root: List of sysctl headers to register on
1945  * @namespaces: Data to compute which lists of sysctl entries are visible
1946  * @path: The path to the directory the sysctl table is in.
1947  * @table: the top-level table structure
1948  *
1949  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1950  * array. A completely 0 filled entry terminates the table.
1951  *
1952  * The members of the &struct ctl_table structure are used as follows:
1953  *
1954  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1955  *            must be unique within that level of sysctl
1956  *
1957  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1958  *            enter a sysctl file
1959  *
1960  * data - a pointer to data for use by proc_handler
1961  *
1962  * maxlen - the maximum size in bytes of the data
1963  *
1964  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1965  *
1966  * child - a pointer to the child sysctl table if this entry is a directory, or
1967  *         %NULL.
1968  *
1969  * proc_handler - the text handler routine (described below)
1970  *
1971  * strategy - the strategy routine (described below)
1972  *
1973  * de - for internal use by the sysctl routines
1974  *
1975  * extra1, extra2 - extra pointers usable by the proc handler routines
1976  *
1977  * Leaf nodes in the sysctl tree will be represented by a single file
1978  * under /proc; non-leaf nodes will be represented by directories.
1979  *
1980  * sysctl(2) can automatically manage read and write requests through
1981  * the sysctl table.  The data and maxlen fields of the ctl_table
1982  * struct enable minimal validation of the values being written to be
1983  * performed, and the mode field allows minimal authentication.
1984  *
1985  * More sophisticated management can be enabled by the provision of a
1986  * strategy routine with the table entry.  This will be called before
1987  * any automatic read or write of the data is performed.
1988  *
1989  * The strategy routine may return
1990  *
1991  * < 0 - Error occurred (error is passed to user process)
1992  *
1993  * 0   - OK - proceed with automatic read or write.
1994  *
1995  * > 0 - OK - read or write has been done by the strategy routine, so
1996  *       return immediately.
1997  *
1998  * There must be a proc_handler routine for any terminal nodes
1999  * mirrored under /proc/sys (non-terminals are handled by a built-in
2000  * directory handler).  Several default handlers are available to
2001  * cover common cases -
2002  *
2003  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
2004  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
2005  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
2006  *
2007  * It is the handler's job to read the input buffer from user memory
2008  * and process it. The handler should return 0 on success.
2009  *
2010  * This routine returns %NULL on a failure to register, and a pointer
2011  * to the table header on success.
2012  */
2013 struct ctl_table_header *__register_sysctl_paths(
2014         struct ctl_table_root *root,
2015         struct nsproxy *namespaces,
2016         const struct ctl_path *path, struct ctl_table *table)
2017 {
2018         struct ctl_table_header *header;
2019         struct ctl_table *new, **prevp;
2020         unsigned int n, npath;
2021         struct ctl_table_set *set;
2022
2023         /* Count the path components */
2024         for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
2025                 ;
2026
2027         /*
2028          * For each path component, allocate a 2-element ctl_table array.
2029          * The first array element will be filled with the sysctl entry
2030          * for this, the second will be the sentinel (ctl_name == 0).
2031          *
2032          * We allocate everything in one go so that we don't have to
2033          * worry about freeing additional memory in unregister_sysctl_table.
2034          */
2035         header = kzalloc(sizeof(struct ctl_table_header) +
2036                          (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
2037         if (!header)
2038                 return NULL;
2039
2040         new = (struct ctl_table *) (header + 1);
2041
2042         /* Now connect the dots */
2043         prevp = &header->ctl_table;
2044         for (n = 0; n < npath; ++n, ++path) {
2045                 /* Copy the procname */
2046                 new->procname = path->procname;
2047                 new->ctl_name = path->ctl_name;
2048                 new->mode     = 0555;
2049
2050                 *prevp = new;
2051                 prevp = &new->child;
2052
2053                 new += 2;
2054         }
2055         *prevp = table;
2056         header->ctl_table_arg = table;
2057
2058         INIT_LIST_HEAD(&header->ctl_entry);
2059         header->used = 0;
2060         header->unregistering = NULL;
2061         header->root = root;
2062         sysctl_set_parent(NULL, header->ctl_table);
2063         header->count = 1;
2064 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2065         if (sysctl_check_table(namespaces, header->ctl_table)) {
2066                 kfree(header);
2067                 return NULL;
2068         }
2069 #endif
2070         spin_lock(&sysctl_lock);
2071         header->set = lookup_header_set(root, namespaces);
2072         header->attached_by = header->ctl_table;
2073         header->attached_to = root_table;
2074         header->parent = &root_table_header;
2075         for (set = header->set; set; set = set->parent) {
2076                 struct ctl_table_header *p;
2077                 list_for_each_entry(p, &set->list, ctl_entry) {
2078                         if (p->unregistering)
2079                                 continue;
2080                         try_attach(p, header);
2081                 }
2082         }
2083         header->parent->count++;
2084         list_add_tail(&header->ctl_entry, &header->set->list);
2085         spin_unlock(&sysctl_lock);
2086
2087         return header;
2088 }
2089
2090 /**
2091  * register_sysctl_table_path - register a sysctl table hierarchy
2092  * @path: The path to the directory the sysctl table is in.
2093  * @table: the top-level table structure
2094  *
2095  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2096  * array. A completely 0 filled entry terminates the table.
2097  *
2098  * See __register_sysctl_paths for more details.
2099  */
2100 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2101                                                 struct ctl_table *table)
2102 {
2103         return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2104                                         path, table);
2105 }
2106
2107 /**
2108  * register_sysctl_table - register a sysctl table hierarchy
2109  * @table: the top-level table structure
2110  *
2111  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2112  * array. A completely 0 filled entry terminates the table.
2113  *
2114  * See register_sysctl_paths for more details.
2115  */
2116 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2117 {
2118         static const struct ctl_path null_path[] = { {} };
2119
2120         return register_sysctl_paths(null_path, table);
2121 }
2122
2123 /**
2124  * unregister_sysctl_table - unregister a sysctl table hierarchy
2125  * @header: the header returned from register_sysctl_table
2126  *
2127  * Unregisters the sysctl table and all children. proc entries may not
2128  * actually be removed until they are no longer used by anyone.
2129  */
2130 void unregister_sysctl_table(struct ctl_table_header * header)
2131 {
2132         might_sleep();
2133
2134         if (header == NULL)
2135                 return;
2136
2137         spin_lock(&sysctl_lock);
2138         start_unregistering(header);
2139         if (!--header->parent->count) {
2140                 WARN_ON(1);
2141                 kfree(header->parent);
2142         }
2143         if (!--header->count)
2144                 kfree(header);
2145         spin_unlock(&sysctl_lock);
2146 }
2147
2148 int sysctl_is_seen(struct ctl_table_header *p)
2149 {
2150         struct ctl_table_set *set = p->set;
2151         int res;
2152         spin_lock(&sysctl_lock);
2153         if (p->unregistering)
2154                 res = 0;
2155         else if (!set->is_seen)
2156                 res = 1;
2157         else
2158                 res = set->is_seen(set);
2159         spin_unlock(&sysctl_lock);
2160         return res;
2161 }
2162
2163 void setup_sysctl_set(struct ctl_table_set *p,
2164         struct ctl_table_set *parent,
2165         int (*is_seen)(struct ctl_table_set *))
2166 {
2167         INIT_LIST_HEAD(&p->list);
2168         p->parent = parent ? parent : &sysctl_table_root.default_set;
2169         p->is_seen = is_seen;
2170 }
2171
2172 #else /* !CONFIG_SYSCTL */
2173 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2174 {
2175         return NULL;
2176 }
2177
2178 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2179                                                     struct ctl_table *table)
2180 {
2181         return NULL;
2182 }
2183
2184 void unregister_sysctl_table(struct ctl_table_header * table)
2185 {
2186 }
2187
2188 void setup_sysctl_set(struct ctl_table_set *p,
2189         struct ctl_table_set *parent,
2190         int (*is_seen)(struct ctl_table_set *))
2191 {
2192 }
2193
2194 void sysctl_head_put(struct ctl_table_header *head)
2195 {
2196 }
2197
2198 #endif /* CONFIG_SYSCTL */
2199
2200 /*
2201  * /proc/sys support
2202  */
2203
2204 #ifdef CONFIG_PROC_SYSCTL
2205
2206 static int _proc_do_string(void* data, int maxlen, int write,
2207                            struct file *filp, void __user *buffer,
2208                            size_t *lenp, loff_t *ppos)
2209 {
2210         size_t len;
2211         char __user *p;
2212         char c;
2213
2214         if (!data || !maxlen || !*lenp) {
2215                 *lenp = 0;
2216                 return 0;
2217         }
2218
2219         if (write) {
2220                 len = 0;
2221                 p = buffer;
2222                 while (len < *lenp) {
2223                         if (get_user(c, p++))
2224                                 return -EFAULT;
2225                         if (c == 0 || c == '\n')
2226                                 break;
2227                         len++;
2228                 }
2229                 if (len >= maxlen)
2230                         len = maxlen-1;
2231                 if(copy_from_user(data, buffer, len))
2232                         return -EFAULT;
2233                 ((char *) data)[len] = 0;
2234                 *ppos += *lenp;
2235         } else {
2236                 len = strlen(data);
2237                 if (len > maxlen)
2238                         len = maxlen;
2239
2240                 if (*ppos > len) {
2241                         *lenp = 0;
2242                         return 0;
2243                 }
2244
2245                 data += *ppos;
2246                 len  -= *ppos;
2247
2248                 if (len > *lenp)
2249                         len = *lenp;
2250                 if (len)
2251                         if(copy_to_user(buffer, data, len))
2252                                 return -EFAULT;
2253                 if (len < *lenp) {
2254                         if(put_user('\n', ((char __user *) buffer) + len))
2255                                 return -EFAULT;
2256                         len++;
2257                 }
2258                 *lenp = len;
2259                 *ppos += len;
2260         }
2261         return 0;
2262 }
2263
2264 /**
2265  * proc_dostring - read a string sysctl
2266  * @table: the sysctl table
2267  * @write: %TRUE if this is a write to the sysctl file
2268  * @filp: the file structure
2269  * @buffer: the user buffer
2270  * @lenp: the size of the user buffer
2271  * @ppos: file position
2272  *
2273  * Reads/writes a string from/to the user buffer. If the kernel
2274  * buffer provided is not large enough to hold the string, the
2275  * string is truncated. The copied string is %NULL-terminated.
2276  * If the string is being read by the user process, it is copied
2277  * and a newline '\n' is added. It is truncated if the buffer is
2278  * not large enough.
2279  *
2280  * Returns 0 on success.
2281  */
2282 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2283                   void __user *buffer, size_t *lenp, loff_t *ppos)
2284 {
2285         return _proc_do_string(table->data, table->maxlen, write, filp,
2286                                buffer, lenp, ppos);
2287 }
2288
2289
2290 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2291                                  int *valp,
2292                                  int write, void *data)
2293 {
2294         if (write) {
2295                 *valp = *negp ? -*lvalp : *lvalp;
2296         } else {
2297                 int val = *valp;
2298                 if (val < 0) {
2299                         *negp = -1;
2300                         *lvalp = (unsigned long)-val;
2301                 } else {
2302                         *negp = 0;
2303                         *lvalp = (unsigned long)val;
2304                 }
2305         }
2306         return 0;
2307 }
2308
2309 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2310                   int write, struct file *filp, void __user *buffer,
2311                   size_t *lenp, loff_t *ppos,
2312                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2313                               int write, void *data),
2314                   void *data)
2315 {
2316 #define TMPBUFLEN 21
2317         int *i, vleft, first = 1, neg;
2318         unsigned long lval;
2319         size_t left, len;
2320
2321         char buf[TMPBUFLEN], *p;
2322         char __user *s = buffer;
2323
2324         if (!tbl_data || !table->maxlen || !*lenp ||
2325             (*ppos && !write)) {
2326                 *lenp = 0;
2327                 return 0;
2328         }
2329
2330         i = (int *) tbl_data;
2331         vleft = table->maxlen / sizeof(*i);
2332         left = *lenp;
2333
2334         if (!conv)
2335                 conv = do_proc_dointvec_conv;
2336
2337         for (; left && vleft--; i++, first=0) {
2338                 if (write) {
2339                         while (left) {
2340                                 char c;
2341                                 if (get_user(c, s))
2342                                         return -EFAULT;
2343                                 if (!isspace(c))
2344                                         break;
2345                                 left--;
2346                                 s++;
2347                         }
2348                         if (!left)
2349                                 break;
2350                         neg = 0;
2351                         len = left;
2352                         if (len > sizeof(buf) - 1)
2353                                 len = sizeof(buf) - 1;
2354                         if (copy_from_user(buf, s, len))
2355                                 return -EFAULT;
2356                         buf[len] = 0;
2357                         p = buf;
2358                         if (*p == '-' && left > 1) {
2359                                 neg = 1;
2360                                 p++;
2361                         }
2362                         if (*p < '0' || *p > '9')
2363                                 break;
2364
2365                         lval = simple_strtoul(p, &p, 0);
2366
2367                         len = p-buf;
2368                         if ((len < left) && *p && !isspace(*p))
2369                                 break;
2370                         s += len;
2371                         left -= len;
2372
2373                         if (conv(&neg, &lval, i, 1, data))
2374                                 break;
2375                 } else {
2376                         p = buf;
2377                         if (!first)
2378                                 *p++ = '\t';
2379
2380                         if (conv(&neg, &lval, i, 0, data))
2381                                 break;
2382
2383                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
2384                         len = strlen(buf);
2385                         if (len > left)
2386                                 len = left;
2387                         if(copy_to_user(s, buf, len))
2388                                 return -EFAULT;
2389                         left -= len;
2390                         s += len;
2391                 }
2392         }
2393
2394         if (!write && !first && left) {
2395                 if(put_user('\n', s))
2396                         return -EFAULT;
2397                 left--, s++;
2398         }
2399         if (write) {
2400                 while (left) {
2401                         char c;
2402                         if (get_user(c, s++))
2403                                 return -EFAULT;
2404                         if (!isspace(c))
2405                                 break;
2406                         left--;
2407                 }
2408         }
2409         if (write && first)
2410                 return -EINVAL;
2411         *lenp -= left;
2412         *ppos += *lenp;
2413         return 0;
2414 #undef TMPBUFLEN
2415 }
2416
2417 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2418                   void __user *buffer, size_t *lenp, loff_t *ppos,
2419                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2420                               int write, void *data),
2421                   void *data)
2422 {
2423         return __do_proc_dointvec(table->data, table, write, filp,
2424                         buffer, lenp, ppos, conv, data);
2425 }
2426
2427 /**
2428  * proc_dointvec - read a vector of integers
2429  * @table: the sysctl table
2430  * @write: %TRUE if this is a write to the sysctl file
2431  * @filp: the file structure
2432  * @buffer: the user buffer
2433  * @lenp: the size of the user buffer
2434  * @ppos: file position
2435  *
2436  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2437  * values from/to the user buffer, treated as an ASCII string.
2438  *
2439  * Returns 0 on success.
2440  */
2441 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2442                      void __user *buffer, size_t *lenp, loff_t *ppos)
2443 {
2444     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2445                             NULL,NULL);
2446 }
2447
2448 /*
2449  * Taint values can only be increased
2450  * This means we can safely use a temporary.
2451  */
2452 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2453                                void __user *buffer, size_t *lenp, loff_t *ppos)
2454 {
2455         struct ctl_table t;
2456         unsigned long tmptaint = get_taint();
2457         int err;
2458
2459         if (write && !capable(CAP_SYS_ADMIN))
2460                 return -EPERM;
2461
2462         t = *table;
2463         t.data = &tmptaint;
2464         err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2465         if (err < 0)
2466                 return err;
2467
2468         if (write) {
2469                 /*
2470                  * Poor man's atomic or. Not worth adding a primitive
2471                  * to everyone's atomic.h for this
2472                  */
2473                 int i;
2474                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2475                         if ((tmptaint >> i) & 1)
2476                                 add_taint(i);
2477                 }
2478         }
2479
2480         return err;
2481 }
2482
2483 struct do_proc_dointvec_minmax_conv_param {
2484         int *min;
2485         int *max;
2486 };
2487
2488 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2489                                         int *valp,
2490                                         int write, void *data)
2491 {
2492         struct do_proc_dointvec_minmax_conv_param *param = data;
2493         if (write) {
2494                 int val = *negp ? -*lvalp : *lvalp;
2495                 if ((param->min && *param->min > val) ||
2496                     (param->max && *param->max < val))
2497                         return -EINVAL;
2498                 *valp = val;
2499         } else {
2500                 int val = *valp;
2501                 if (val < 0) {
2502                         *negp = -1;
2503                         *lvalp = (unsigned long)-val;
2504                 } else {
2505                         *negp = 0;
2506                         *lvalp = (unsigned long)val;
2507                 }
2508         }
2509         return 0;
2510 }
2511
2512 /**
2513  * proc_dointvec_minmax - read a vector of integers with min/max values
2514  * @table: the sysctl table
2515  * @write: %TRUE if this is a write to the sysctl file
2516  * @filp: the file structure
2517  * @buffer: the user buffer
2518  * @lenp: the size of the user buffer
2519  * @ppos: file position
2520  *
2521  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2522  * values from/to the user buffer, treated as an ASCII string.
2523  *
2524  * This routine will ensure the values are within the range specified by
2525  * table->extra1 (min) and table->extra2 (max).
2526  *
2527  * Returns 0 on success.
2528  */
2529 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2530                   void __user *buffer, size_t *lenp, loff_t *ppos)
2531 {
2532         struct do_proc_dointvec_minmax_conv_param param = {
2533                 .min = (int *) table->extra1,
2534                 .max = (int *) table->extra2,
2535         };
2536         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2537                                 do_proc_dointvec_minmax_conv, &param);
2538 }
2539
2540 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2541                                      struct file *filp,
2542                                      void __user *buffer,
2543                                      size_t *lenp, loff_t *ppos,
2544                                      unsigned long convmul,
2545                                      unsigned long convdiv)
2546 {
2547 #define TMPBUFLEN 21
2548         unsigned long *i, *min, *max, val;
2549         int vleft, first=1, neg;
2550         size_t len, left;
2551         char buf[TMPBUFLEN], *p;
2552         char __user *s = buffer;
2553
2554         if (!data || !table->maxlen || !*lenp ||
2555             (*ppos && !write)) {
2556                 *lenp = 0;
2557                 return 0;
2558         }
2559
2560         i = (unsigned long *) data;
2561         min = (unsigned long *) table->extra1;
2562         max = (unsigned long *) table->extra2;
2563         vleft = table->maxlen / sizeof(unsigned long);
2564         left = *lenp;
2565
2566         for (; left && vleft--; i++, min++, max++, first=0) {
2567                 if (write) {
2568                         while (left) {
2569                                 char c;
2570                                 if (get_user(c, s))
2571                                         return -EFAULT;
2572                                 if (!isspace(c))
2573                                         break;
2574                                 left--;
2575                                 s++;
2576                         }
2577                         if (!left)
2578                                 break;
2579                         neg = 0;
2580                         len = left;
2581                         if (len > TMPBUFLEN-1)
2582                                 len = TMPBUFLEN-1;
2583                         if (copy_from_user(buf, s, len))
2584                                 return -EFAULT;
2585                         buf[len] = 0;
2586                         p = buf;
2587                         if (*p == '-' && left > 1) {
2588                                 neg = 1;
2589                                 p++;
2590                         }
2591                         if (*p < '0' || *p > '9')
2592                                 break;
2593                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2594                         len = p-buf;
2595                         if ((len < left) && *p && !isspace(*p))
2596                                 break;
2597                         if (neg)
2598                                 val = -val;
2599                         s += len;
2600                         left -= len;
2601
2602                         if(neg)
2603                                 continue;
2604                         if ((min && val < *min) || (max && val > *max))
2605                                 continue;
2606                         *i = val;
2607                 } else {
2608                         p = buf;
2609                         if (!first)
2610                                 *p++ = '\t';
2611                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2612                         len = strlen(buf);
2613                         if (len > left)
2614                                 len = left;
2615                         if(copy_to_user(s, buf, len))
2616                                 return -EFAULT;
2617                         left -= len;
2618                         s += len;
2619                 }
2620         }
2621
2622         if (!write && !first && left) {
2623                 if(put_user('\n', s))
2624                         return -EFAULT;
2625                 left--, s++;
2626         }
2627         if (write) {
2628                 while (left) {
2629                         char c;
2630                         if (get_user(c, s++))
2631                                 return -EFAULT;
2632                         if (!isspace(c))
2633                                 break;
2634                         left--;
2635                 }
2636         }
2637         if (write && first)
2638                 return -EINVAL;
2639         *lenp -= left;
2640         *ppos += *lenp;
2641         return 0;
2642 #undef TMPBUFLEN
2643 }
2644
2645 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2646                                      struct file *filp,
2647                                      void __user *buffer,
2648                                      size_t *lenp, loff_t *ppos,
2649                                      unsigned long convmul,
2650                                      unsigned long convdiv)
2651 {
2652         return __do_proc_doulongvec_minmax(table->data, table, write,
2653                         filp, buffer, lenp, ppos, convmul, convdiv);
2654 }
2655
2656 /**
2657  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2658  * @table: the sysctl table
2659  * @write: %TRUE if this is a write to the sysctl file
2660  * @filp: the file structure
2661  * @buffer: the user buffer
2662  * @lenp: the size of the user buffer
2663  * @ppos: file position
2664  *
2665  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2666  * values from/to the user buffer, treated as an ASCII string.
2667  *
2668  * This routine will ensure the values are within the range specified by
2669  * table->extra1 (min) and table->extra2 (max).
2670  *
2671  * Returns 0 on success.
2672  */
2673 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2674                            void __user *buffer, size_t *lenp, loff_t *ppos)
2675 {
2676     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2677 }
2678
2679 /**
2680  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2681  * @table: the sysctl table
2682  * @write: %TRUE if this is a write to the sysctl file
2683  * @filp: the file structure
2684  * @buffer: the user buffer
2685  * @lenp: the size of the user buffer
2686  * @ppos: file position
2687  *
2688  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2689  * values from/to the user buffer, treated as an ASCII string. The values
2690  * are treated as milliseconds, and converted to jiffies when they are stored.
2691  *
2692  * This routine will ensure the values are within the range specified by
2693  * table->extra1 (min) and table->extra2 (max).
2694  *
2695  * Returns 0 on success.
2696  */
2697 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2698                                       struct file *filp,
2699                                       void __user *buffer,
2700                                       size_t *lenp, loff_t *ppos)
2701 {
2702     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2703                                      lenp, ppos, HZ, 1000l);
2704 }
2705
2706
2707 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2708                                          int *valp,
2709                                          int write, void *data)
2710 {
2711         if (write) {
2712                 if (*lvalp > LONG_MAX / HZ)
2713                         return 1;
2714                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2715         } else {
2716                 int val = *valp;
2717                 unsigned long lval;
2718                 if (val < 0) {
2719                         *negp = -1;
2720                         lval = (unsigned long)-val;
2721                 } else {
2722                         *negp = 0;
2723                         lval = (unsigned long)val;
2724                 }
2725                 *lvalp = lval / HZ;
2726         }
2727         return 0;
2728 }
2729
2730 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2731                                                 int *valp,
2732                                                 int write, void *data)
2733 {
2734         if (write) {
2735                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2736                         return 1;
2737                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2738         } else {
2739                 int val = *valp;
2740                 unsigned long lval;
2741                 if (val < 0) {
2742                         *negp = -1;
2743                         lval = (unsigned long)-val;
2744                 } else {
2745                         *negp = 0;
2746                         lval = (unsigned long)val;
2747                 }
2748                 *lvalp = jiffies_to_clock_t(lval);
2749         }
2750         return 0;
2751 }
2752
2753 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2754                                             int *valp,
2755                                             int write, void *data)
2756 {
2757         if (write) {
2758                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2759         } else {
2760                 int val = *valp;
2761                 unsigned long lval;
2762                 if (val < 0) {
2763                         *negp = -1;
2764                         lval = (unsigned long)-val;
2765                 } else {
2766                         *negp = 0;
2767                         lval = (unsigned long)val;
2768                 }
2769                 *lvalp = jiffies_to_msecs(lval);
2770         }
2771         return 0;
2772 }
2773
2774 /**
2775  * proc_dointvec_jiffies - read a vector of integers as seconds
2776  * @table: the sysctl table
2777  * @write: %TRUE if this is a write to the sysctl file
2778  * @filp: the file structure
2779  * @buffer: the user buffer
2780  * @lenp: the size of the user buffer
2781  * @ppos: file position
2782  *
2783  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2784  * values from/to the user buffer, treated as an ASCII string.
2785  * The values read are assumed to be in seconds, and are converted into
2786  * jiffies.
2787  *
2788  * Returns 0 on success.
2789  */
2790 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2791                           void __user *buffer, size_t *lenp, loff_t *ppos)
2792 {
2793     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2794                             do_proc_dointvec_jiffies_conv,NULL);
2795 }
2796
2797 /**
2798  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2799  * @table: the sysctl table
2800  * @write: %TRUE if this is a write to the sysctl file
2801  * @filp: the file structure
2802  * @buffer: the user buffer
2803  * @lenp: the size of the user buffer
2804  * @ppos: pointer to the file position
2805  *
2806  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2807  * values from/to the user buffer, treated as an ASCII string.
2808  * The values read are assumed to be in 1/USER_HZ seconds, and
2809  * are converted into jiffies.
2810  *
2811  * Returns 0 on success.
2812  */
2813 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2814                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2815 {
2816     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2817                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2818 }
2819
2820 /**
2821  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2822  * @table: the sysctl table
2823  * @write: %TRUE if this is a write to the sysctl file
2824  * @filp: the file structure
2825  * @buffer: the user buffer
2826  * @lenp: the size of the user buffer
2827  * @ppos: file position
2828  * @ppos: the current position in the file
2829  *
2830  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2831  * values from/to the user buffer, treated as an ASCII string.
2832  * The values read are assumed to be in 1/1000 seconds, and
2833  * are converted into jiffies.
2834  *
2835  * Returns 0 on success.
2836  */
2837 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2838                              void __user *buffer, size_t *lenp, loff_t *ppos)
2839 {
2840         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2841                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2842 }
2843
2844 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2845                            void __user *buffer, size_t *lenp, loff_t *ppos)
2846 {
2847         struct pid *new_pid;
2848         pid_t tmp;
2849         int r;
2850
2851         tmp = pid_vnr(cad_pid);
2852
2853         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2854                                lenp, ppos, NULL, NULL);
2855         if (r || !write)
2856                 return r;
2857
2858         new_pid = find_get_pid(tmp);
2859         if (!new_pid)
2860                 return -ESRCH;
2861
2862         put_pid(xchg(&cad_pid, new_pid));
2863         return 0;
2864 }
2865
2866 #else /* CONFIG_PROC_FS */
2867
2868 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2869                   void __user *buffer, size_t *lenp, loff_t *ppos)
2870 {
2871         return -ENOSYS;
2872 }
2873
2874 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2875                   void __user *buffer, size_t *lenp, loff_t *ppos)
2876 {
2877         return -ENOSYS;
2878 }
2879
2880 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2881                     void __user *buffer, size_t *lenp, loff_t *ppos)
2882 {
2883         return -ENOSYS;
2884 }
2885
2886 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2887                     void __user *buffer, size_t *lenp, loff_t *ppos)
2888 {
2889         return -ENOSYS;
2890 }
2891
2892 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2893                     void __user *buffer, size_t *lenp, loff_t *ppos)
2894 {
2895         return -ENOSYS;
2896 }
2897
2898 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2899                              void __user *buffer, size_t *lenp, loff_t *ppos)
2900 {
2901         return -ENOSYS;
2902 }
2903
2904 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2905                     void __user *buffer, size_t *lenp, loff_t *ppos)
2906 {
2907         return -ENOSYS;
2908 }
2909
2910 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2911                                       struct file *filp,
2912                                       void __user *buffer,
2913                                       size_t *lenp, loff_t *ppos)
2914 {
2915     return -ENOSYS;
2916 }
2917
2918
2919 #endif /* CONFIG_PROC_FS */
2920
2921
2922 #ifdef CONFIG_SYSCTL_SYSCALL
2923 /*
2924  * General sysctl support routines
2925  */
2926
2927 /* The generic sysctl data routine (used if no strategy routine supplied) */
2928 int sysctl_data(struct ctl_table *table,
2929                 void __user *oldval, size_t __user *oldlenp,
2930                 void __user *newval, size_t newlen)
2931 {
2932         size_t len;
2933
2934         /* Get out of I don't have a variable */
2935         if (!table->data || !table->maxlen)
2936                 return -ENOTDIR;
2937
2938         if (oldval && oldlenp) {
2939                 if (get_user(len, oldlenp))
2940                         return -EFAULT;
2941                 if (len) {
2942                         if (len > table->maxlen)
2943                                 len = table->maxlen;
2944                         if (copy_to_user(oldval, table->data, len))
2945                                 return -EFAULT;
2946                         if (put_user(len, oldlenp))
2947                                 return -EFAULT;
2948                 }
2949         }
2950
2951         if (newval && newlen) {
2952                 if (newlen > table->maxlen)
2953                         newlen = table->maxlen;
2954
2955                 if (copy_from_user(table->data, newval, newlen))
2956                         return -EFAULT;
2957         }
2958         return 1;
2959 }
2960
2961 /* The generic string strategy routine: */
2962 int sysctl_string(struct ctl_table *table,
2963                   void __user *oldval, size_t __user *oldlenp,
2964                   void __user *newval, size_t newlen)
2965 {
2966         if (!table->data || !table->maxlen)
2967                 return -ENOTDIR;
2968
2969         if (oldval && oldlenp) {
2970                 size_t bufsize;
2971                 if (get_user(bufsize, oldlenp))
2972                         return -EFAULT;
2973                 if (bufsize) {
2974                         size_t len = strlen(table->data), copied;
2975
2976                         /* This shouldn't trigger for a well-formed sysctl */
2977                         if (len > table->maxlen)
2978                                 len = table->maxlen;
2979
2980                         /* Copy up to a max of bufsize-1 bytes of the string */
2981                         copied = (len >= bufsize) ? bufsize - 1 : len;
2982
2983                         if (copy_to_user(oldval, table->data, copied) ||
2984                             put_user(0, (char __user *)(oldval + copied)))
2985                                 return -EFAULT;
2986                         if (put_user(len, oldlenp))
2987                                 return -EFAULT;
2988                 }
2989         }
2990         if (newval && newlen) {
2991                 size_t len = newlen;
2992                 if (len > table->maxlen)
2993                         len = table->maxlen;
2994                 if(copy_from_user(table->data, newval, len))
2995                         return -EFAULT;
2996                 if (len == table->maxlen)
2997                         len--;
2998                 ((char *) table->data)[len] = 0;
2999         }
3000         return 1;
3001 }
3002
3003 /*
3004  * This function makes sure that all of the integers in the vector
3005  * are between the minimum and maximum values given in the arrays
3006  * table->extra1 and table->extra2, respectively.
3007  */
3008 int sysctl_intvec(struct ctl_table *table,
3009                 void __user *oldval, size_t __user *oldlenp,
3010                 void __user *newval, size_t newlen)
3011 {
3012
3013         if (newval && newlen) {
3014                 int __user *vec = (int __user *) newval;
3015                 int *min = (int *) table->extra1;
3016                 int *max = (int *) table->extra2;
3017                 size_t length;
3018                 int i;
3019
3020                 if (newlen % sizeof(int) != 0)
3021                         return -EINVAL;
3022
3023                 if (!table->extra1 && !table->extra2)
3024                         return 0;
3025
3026                 if (newlen > table->maxlen)
3027                         newlen = table->maxlen;
3028                 length = newlen / sizeof(int);
3029
3030                 for (i = 0; i < length; i++) {
3031                         int value;
3032                         if (get_user(value, vec + i))
3033                                 return -EFAULT;
3034                         if (min && value < min[i])
3035                                 return -EINVAL;
3036                         if (max && value > max[i])
3037                                 return -EINVAL;
3038                 }
3039         }
3040         return 0;
3041 }
3042
3043 /* Strategy function to convert jiffies to seconds */
3044 int sysctl_jiffies(struct ctl_table *table,
3045                 void __user *oldval, size_t __user *oldlenp,
3046                 void __user *newval, size_t newlen)
3047 {
3048         if (oldval && oldlenp) {
3049                 size_t olen;
3050
3051                 if (get_user(olen, oldlenp))
3052                         return -EFAULT;
3053                 if (olen) {
3054                         int val;
3055
3056                         if (olen < sizeof(int))
3057                                 return -EINVAL;
3058
3059                         val = *(int *)(table->data) / HZ;
3060                         if (put_user(val, (int __user *)oldval))
3061                                 return -EFAULT;
3062                         if (put_user(sizeof(int), oldlenp))
3063                                 return -EFAULT;
3064                 }
3065         }
3066         if (newval && newlen) {
3067                 int new;
3068                 if (newlen != sizeof(int))
3069                         return -EINVAL;
3070                 if (get_user(new, (int __user *)newval))
3071                         return -EFAULT;
3072                 *(int *)(table->data) = new*HZ;
3073         }
3074         return 1;
3075 }
3076
3077 /* Strategy function to convert jiffies to seconds */
3078 int sysctl_ms_jiffies(struct ctl_table *table,
3079                 void __user *oldval, size_t __user *oldlenp,
3080                 void __user *newval, size_t newlen)
3081 {
3082         if (oldval && oldlenp) {
3083                 size_t olen;
3084
3085                 if (get_user(olen, oldlenp))
3086                         return -EFAULT;
3087                 if (olen) {
3088                         int val;
3089
3090                         if (olen < sizeof(int))
3091                                 return -EINVAL;
3092
3093                         val = jiffies_to_msecs(*(int *)(table->data));
3094                         if (put_user(val, (int __user *)oldval))
3095                                 return -EFAULT;
3096                         if (put_user(sizeof(int), oldlenp))
3097                                 return -EFAULT;
3098                 }
3099         }
3100         if (newval && newlen) {
3101                 int new;
3102                 if (newlen != sizeof(int))
3103                         return -EINVAL;
3104                 if (get_user(new, (int __user *)newval))
3105                         return -EFAULT;
3106                 *(int *)(table->data) = msecs_to_jiffies(new);
3107         }
3108         return 1;
3109 }
3110
3111
3112
3113 #else /* CONFIG_SYSCTL_SYSCALL */
3114
3115
3116 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3117 {
3118         struct __sysctl_args tmp;
3119         int error;
3120
3121         if (copy_from_user(&tmp, args, sizeof(tmp)))
3122                 return -EFAULT;
3123
3124         error = deprecated_sysctl_warning(&tmp);
3125
3126         /* If no error reading the parameters then just -ENOSYS ... */
3127         if (!error)
3128                 error = -ENOSYS;
3129
3130         return error;
3131 }
3132
3133 int sysctl_data(struct ctl_table *table,
3134                   void __user *oldval, size_t __user *oldlenp,
3135                   void __user *newval, size_t newlen)
3136 {
3137         return -ENOSYS;
3138 }
3139
3140 int sysctl_string(struct ctl_table *table,
3141                   void __user *oldval, size_t __user *oldlenp,
3142                   void __user *newval, size_t newlen)
3143 {
3144         return -ENOSYS;
3145 }
3146
3147 int sysctl_intvec(struct ctl_table *table,
3148                 void __user *oldval, size_t __user *oldlenp,
3149                 void __user *newval, size_t newlen)
3150 {
3151         return -ENOSYS;
3152 }
3153
3154 int sysctl_jiffies(struct ctl_table *table,
3155                 void __user *oldval, size_t __user *oldlenp,
3156                 void __user *newval, size_t newlen)
3157 {
3158         return -ENOSYS;
3159 }
3160
3161 int sysctl_ms_jiffies(struct ctl_table *table,
3162                 void __user *oldval, size_t __user *oldlenp,
3163                 void __user *newval, size_t newlen)
3164 {
3165         return -ENOSYS;
3166 }
3167
3168 #endif /* CONFIG_SYSCTL_SYSCALL */
3169
3170 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3171 {
3172         static int msg_count;
3173         int name[CTL_MAXNAME];
3174         int i;
3175
3176         /* Check args->nlen. */
3177         if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3178                 return -ENOTDIR;
3179
3180         /* Read in the sysctl name for better debug message logging */
3181         for (i = 0; i < args->nlen; i++)
3182                 if (get_user(name[i], args->name + i))
3183                         return -EFAULT;
3184
3185         /* Ignore accesses to kernel.version */
3186         if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3187                 return 0;
3188
3189         if (msg_count < 5) {
3190                 msg_count++;
3191                 printk(KERN_INFO
3192                         "warning: process `%s' used the deprecated sysctl "
3193                         "system call with ", current->comm);
3194                 for (i = 0; i < args->nlen; i++)
3195                         printk("%d.", name[i]);
3196                 printk("\n");
3197         }
3198         return 0;
3199 }
3200
3201 /*
3202  * No sense putting this after each symbol definition, twice,
3203  * exception granted :-)
3204  */
3205 EXPORT_SYMBOL(proc_dointvec);
3206 EXPORT_SYMBOL(proc_dointvec_jiffies);
3207 EXPORT_SYMBOL(proc_dointvec_minmax);
3208 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3209 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3210 EXPORT_SYMBOL(proc_dostring);
3211 EXPORT_SYMBOL(proc_doulongvec_minmax);
3212 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3213 EXPORT_SYMBOL(register_sysctl_table);
3214 EXPORT_SYMBOL(register_sysctl_paths);
3215 EXPORT_SYMBOL(sysctl_intvec);
3216 EXPORT_SYMBOL(sysctl_jiffies);
3217 EXPORT_SYMBOL(sysctl_ms_jiffies);
3218 EXPORT_SYMBOL(sysctl_string);
3219 EXPORT_SYMBOL(sysctl_data);
3220 EXPORT_SYMBOL(unregister_sysctl_table);