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