kernel/sysctl.c

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