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/aio.h>
  23 #include <linux/mm.h>
  24 #include <linux/swap.h>
  25 #include <linux/slab.h>
  26 #include <linux/sysctl.h>
  27 #include <linux/bitmap.h>
  28 #include <linux/signal.h>
  29 #include <linux/printk.h>
  30 #include <linux/proc_fs.h>
  31 #include <linux/security.h>
  32 #include <linux/ctype.h>
  33 #include <linux/kmemcheck.h>
  34 #include <linux/kmemleak.h>
  35 #include <linux/fs.h>
  36 #include <linux/init.h>
  37 #include <linux/kernel.h>
  38 #include <linux/kobject.h>
  39 #include <linux/net.h>
  40 #include <linux/sysrq.h>
  41 #include <linux/highuid.h>
  42 #include <linux/writeback.h>
  43 #include <linux/ratelimit.h>
  44 #include <linux/compaction.h>
  45 #include <linux/hugetlb.h>
  46 #include <linux/initrd.h>
  47 #include <linux/key.h>
  48 #include <linux/times.h>
  49 #include <linux/limits.h>
  50 #include <linux/dcache.h>
  51 #include <linux/dnotify.h>
  52 #include <linux/syscalls.h>
  53 #include <linux/vmstat.h>
  54 #include <linux/nfs_fs.h>
  55 #include <linux/acpi.h>
  56 #include <linux/reboot.h>
  57 #include <linux/ftrace.h>
  58 #include <linux/perf_event.h>
  59 #include <linux/kprobes.h>
  60 #include <linux/pipe_fs_i.h>
  61 #include <linux/oom.h>
  62 #include <linux/kmod.h>
  63 #include <linux/capability.h>
  64 #include <linux/binfmts.h>
  65 #include <linux/sched/sysctl.h>
  66 #include <linux/sched/coredump.h>
  67 #include <linux/kexec.h>
  68 #include <linux/bpf.h>
  69 #include <linux/mount.h>
  70
  71 #include <linux/uaccess.h>
  72 #include <asm/processor.h>
  73
  74 #ifdef CONFIG_X86
  75 #include <asm/nmi.h>
  76 #include <asm/stacktrace.h>
  77 #include <asm/io.h>
  78 #endif
  79 #ifdef CONFIG_SPARC
  80 #include <asm/setup.h>
  81 #endif
  82 #ifdef CONFIG_BSD_PROCESS_ACCT
  83 #include <linux/acct.h>
  84 #endif
  85 #ifdef CONFIG_RT_MUTEXES
  86 #include <linux/rtmutex.h>
  87 #endif
  88 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
  89 #include <linux/lockdep.h>
  90 #endif
  91 #ifdef CONFIG_CHR_DEV_SG
  92 #include <scsi/sg.h>
  93 #endif
  94
  95 #ifdef CONFIG_LOCKUP_DETECTOR
  96 #include <linux/nmi.h>
  97 #endif
  98
  99 #if defined(CONFIG_SYSCTL)
 100
 101 /* External variables not in a header file. */
 102 extern int suid_dumpable;
 103 #ifdef CONFIG_COREDUMP
 104 extern int core_uses_pid;
 105 extern char core_pattern[];
 106 extern unsigned int core_pipe_limit;
 107 #endif
 108 extern int pid_max;
 109 extern int pid_max_min, pid_max_max;
 110 extern int percpu_pagelist_fraction;
 111 extern int latencytop_enabled;
 112 extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
 113 #ifndef CONFIG_MMU
 114 extern int sysctl_nr_trim_pages;
 115 #endif
 116
 117 /* Constants used for minimum and  maximum */
 118 #ifdef CONFIG_LOCKUP_DETECTOR
 119 static int sixty = 60;
 120 #endif
 121
 122 static int __maybe_unused neg_one = -1;
 123
 124 static int zero;
 125 static int __maybe_unused one = 1;
 126 static int __maybe_unused two = 2;
 127 static int __maybe_unused four = 4;
 128 static unsigned long one_ul = 1;
 129 static int one_hundred = 100;
 130 static int one_thousand = 1000;
 131 #ifdef CONFIG_PRINTK
 132 static int ten_thousand = 10000;
 133 #endif
 134 #ifdef CONFIG_PERF_EVENTS
 135 static int six_hundred_forty_kb = 640 * 1024;
 136 #endif
 137
 138 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
 139 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
 140
 141 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 142 static int maxolduid = 65535;
 143 static int minolduid;
 144
 145 static int ngroups_max = NGROUPS_MAX;
 146 static const int cap_last_cap = CAP_LAST_CAP;
 147
 148 /*this is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs */
 149 #ifdef CONFIG_DETECT_HUNG_TASK
 150 static unsigned long hung_task_timeout_max = (LONG_MAX/HZ);
 151 #endif
 152
 153 #ifdef CONFIG_INOTIFY_USER
 154 #include <linux/inotify.h>
 155 #endif
 156 #ifdef CONFIG_SPARC
 157 #endif
 158
 159 #ifdef __hppa__
 160 extern int pwrsw_enabled;
 161 #endif
 162
 163 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
 164 extern int unaligned_enabled;
 165 #endif
 166
 167 #ifdef CONFIG_IA64
 168 extern int unaligned_dump_stack;
 169 #endif
 170
 171 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
 172 extern int no_unaligned_warning;
 173 #endif
 174
 175 #ifdef CONFIG_PROC_SYSCTL
 176
 177 /**
 178  * enum sysctl_writes_mode - supported sysctl write modes
 179  *
 180  * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
 181  *      to be written, and multiple writes on the same sysctl file descriptor
 182  *      will rewrite the sysctl value, regardless of file position. No warning
 183  *      is issued when the initial position is not 0.
 184  * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
 185  *      not 0.
 186  * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
 187  *      file position 0 and the value must be fully contained in the buffer
 188  *      sent to the write syscall. If dealing with strings respect the file
 189  *      position, but restrict this to the max length of the buffer, anything
 190  *      passed the max lenght will be ignored. Multiple writes will append
 191  *      to the buffer.
 192  *
 193  * These write modes control how current file position affects the behavior of
 194  * updating sysctl values through the proc interface on each write.
 195  */
 196 enum sysctl_writes_mode {
 197         SYSCTL_WRITES_LEGACY            = -1,
 198         SYSCTL_WRITES_WARN              = 0,
 199         SYSCTL_WRITES_STRICT            = 1,
 200 };
 201
 202 static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
 203
 204 static int proc_do_cad_pid(struct ctl_table *table, int write,
 205                   void __user *buffer, size_t *lenp, loff_t *ppos);
 206 static int proc_taint(struct ctl_table *table, int write,
 207                                void __user *buffer, size_t *lenp, loff_t *ppos);
 208 #endif
 209
 210 #ifdef CONFIG_PRINTK
 211 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
 212                                 void __user *buffer, size_t *lenp, loff_t *ppos);
 213 #endif
 214
 215 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
 216                 void __user *buffer, size_t *lenp, loff_t *ppos);
 217 #ifdef CONFIG_COREDUMP
 218 static int proc_dostring_coredump(struct ctl_table *table, int write,
 219                 void __user *buffer, size_t *lenp, loff_t *ppos);
 220 #endif
 221
 222 #ifdef CONFIG_MAGIC_SYSRQ
 223 /* Note: sysrq code uses it's own private copy */
 224 static int __sysrq_enabled = CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE;
 225
 226 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
 227                                 void __user *buffer, size_t *lenp,
 228                                 loff_t *ppos)
 229 {
 230         int error;
 231
 232         error = proc_dointvec(table, write, buffer, lenp, ppos);
 233         if (error)
 234                 return error;
 235
 236         if (write)
 237                 sysrq_toggle_support(__sysrq_enabled);
 238
 239         return 0;
 240 }
 241
 242 #endif
 243
 244 static struct ctl_table kern_table[];
 245 static struct ctl_table vm_table[];
 246 static struct ctl_table fs_table[];
 247 static struct ctl_table debug_table[];
 248 static struct ctl_table dev_table[];
 249 extern struct ctl_table random_table[];
 250 #ifdef CONFIG_EPOLL
 251 extern struct ctl_table epoll_table[];
 252 #endif
 253
 254 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 255 int sysctl_legacy_va_layout;
 256 #endif
 257
 258 /* The default sysctl tables: */
 259
 260 static struct ctl_table sysctl_base_table[] = {
 261         {
 262                 .procname       = "kernel",
 263                 .mode           = 0555,
 264                 .child          = kern_table,
 265         },
 266         {
 267                 .procname       = "vm",
 268                 .mode           = 0555,
 269                 .child          = vm_table,
 270         },
 271         {
 272                 .procname       = "fs",
 273                 .mode           = 0555,
 274                 .child          = fs_table,
 275         },
 276         {
 277                 .procname       = "debug",
 278                 .mode           = 0555,
 279                 .child          = debug_table,
 280         },
 281         {
 282                 .procname       = "dev",
 283                 .mode           = 0555,
 284                 .child          = dev_table,
 285         },
 286         { }
 287 };
 288
 289 #ifdef CONFIG_SCHED_DEBUG
 290 static int min_sched_granularity_ns = 100000;           /* 100 usecs */
 291 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
 292 static int min_wakeup_granularity_ns;                   /* 0 usecs */
 293 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
 294 #ifdef CONFIG_SMP
 295 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
 296 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
 297 #endif /* CONFIG_SMP */
 298 #endif /* CONFIG_SCHED_DEBUG */
 299
 300 #ifdef CONFIG_COMPACTION
 301 static int min_extfrag_threshold;
 302 static int max_extfrag_threshold = 1000;
 303 #endif
 304
 305 static struct ctl_table kern_table[] = {
 306         {
 307                 .procname       = "sched_child_runs_first",
 308                 .data           = &sysctl_sched_child_runs_first,
 309                 .maxlen         = sizeof(unsigned int),
 310                 .mode           = 0644,
 311                 .proc_handler   = proc_dointvec,
 312         },
 313 #ifdef CONFIG_SCHED_DEBUG
 314         {
 315                 .procname       = "sched_min_granularity_ns",
 316                 .data           = &sysctl_sched_min_granularity,
 317                 .maxlen         = sizeof(unsigned int),
 318                 .mode           = 0644,
 319                 .proc_handler   = sched_proc_update_handler,
 320                 .extra1         = &min_sched_granularity_ns,
 321                 .extra2         = &max_sched_granularity_ns,
 322         },
 323         {
 324                 .procname       = "sched_latency_ns",
 325                 .data           = &sysctl_sched_latency,
 326                 .maxlen         = sizeof(unsigned int),
 327                 .mode           = 0644,
 328                 .proc_handler   = sched_proc_update_handler,
 329                 .extra1         = &min_sched_granularity_ns,
 330                 .extra2         = &max_sched_granularity_ns,
 331         },
 332         {
 333                 .procname       = "sched_wakeup_granularity_ns",
 334                 .data           = &sysctl_sched_wakeup_granularity,
 335                 .maxlen         = sizeof(unsigned int),
 336                 .mode           = 0644,
 337                 .proc_handler   = sched_proc_update_handler,
 338                 .extra1         = &min_wakeup_granularity_ns,
 339                 .extra2         = &max_wakeup_granularity_ns,
 340         },
 341 #ifdef CONFIG_SMP
 342         {
 343                 .procname       = "sched_tunable_scaling",
 344                 .data           = &sysctl_sched_tunable_scaling,
 345                 .maxlen         = sizeof(enum sched_tunable_scaling),
 346                 .mode           = 0644,
 347                 .proc_handler   = sched_proc_update_handler,
 348                 .extra1         = &min_sched_tunable_scaling,
 349                 .extra2         = &max_sched_tunable_scaling,
 350         },
 351         {
 352                 .procname       = "sched_migration_cost_ns",
 353                 .data           = &sysctl_sched_migration_cost,
 354                 .maxlen         = sizeof(unsigned int),
 355                 .mode           = 0644,
 356                 .proc_handler   = proc_dointvec,
 357         },
 358         {
 359                 .procname       = "sched_nr_migrate",
 360                 .data           = &sysctl_sched_nr_migrate,
 361                 .maxlen         = sizeof(unsigned int),
 362                 .mode           = 0644,
 363                 .proc_handler   = proc_dointvec,
 364         },
 365         {
 366                 .procname       = "sched_time_avg_ms",
 367                 .data           = &sysctl_sched_time_avg,
 368                 .maxlen         = sizeof(unsigned int),
 369                 .mode           = 0644,
 370                 .proc_handler   = proc_dointvec,
 371         },
 372 #ifdef CONFIG_SCHEDSTATS
 373         {
 374                 .procname       = "sched_schedstats",
 375                 .data           = NULL,
 376                 .maxlen         = sizeof(unsigned int),
 377                 .mode           = 0644,
 378                 .proc_handler   = sysctl_schedstats,
 379                 .extra1         = &zero,
 380                 .extra2         = &one,
 381         },
 382 #endif /* CONFIG_SCHEDSTATS */
 383 #endif /* CONFIG_SMP */
 384 #ifdef CONFIG_NUMA_BALANCING
 385         {
 386                 .procname       = "numa_balancing_scan_delay_ms",
 387                 .data           = &sysctl_numa_balancing_scan_delay,
 388                 .maxlen         = sizeof(unsigned int),
 389                 .mode           = 0644,
 390                 .proc_handler   = proc_dointvec,
 391         },
 392         {
 393                 .procname       = "numa_balancing_scan_period_min_ms",
 394                 .data           = &sysctl_numa_balancing_scan_period_min,
 395                 .maxlen         = sizeof(unsigned int),
 396                 .mode           = 0644,
 397                 .proc_handler   = proc_dointvec,
 398         },
 399         {
 400                 .procname       = "numa_balancing_scan_period_max_ms",
 401                 .data           = &sysctl_numa_balancing_scan_period_max,
 402                 .maxlen         = sizeof(unsigned int),
 403                 .mode           = 0644,
 404                 .proc_handler   = proc_dointvec,
 405         },
 406         {
 407                 .procname       = "numa_balancing_scan_size_mb",
 408                 .data           = &sysctl_numa_balancing_scan_size,
 409                 .maxlen         = sizeof(unsigned int),
 410                 .mode           = 0644,
 411                 .proc_handler   = proc_dointvec_minmax,
 412                 .extra1         = &one,
 413         },
 414         {
 415                 .procname       = "numa_balancing",
 416                 .data           = NULL, /* filled in by handler */
 417                 .maxlen         = sizeof(unsigned int),
 418                 .mode           = 0644,
 419                 .proc_handler   = sysctl_numa_balancing,
 420                 .extra1         = &zero,
 421                 .extra2         = &one,
 422         },
 423 #endif /* CONFIG_NUMA_BALANCING */
 424 #endif /* CONFIG_SCHED_DEBUG */
 425         {
 426                 .procname       = "sched_rt_period_us",
 427                 .data           = &sysctl_sched_rt_period,
 428                 .maxlen         = sizeof(unsigned int),
 429                 .mode           = 0644,
 430                 .proc_handler   = sched_rt_handler,
 431         },
 432         {
 433                 .procname       = "sched_rt_runtime_us",
 434                 .data           = &sysctl_sched_rt_runtime,
 435                 .maxlen         = sizeof(int),
 436                 .mode           = 0644,
 437                 .proc_handler   = sched_rt_handler,
 438         },
 439         {
 440                 .procname       = "sched_rr_timeslice_ms",
 441                 .data           = &sysctl_sched_rr_timeslice,
 442                 .maxlen         = sizeof(int),
 443                 .mode           = 0644,
 444                 .proc_handler   = sched_rr_handler,
 445         },
 446 #ifdef CONFIG_SCHED_AUTOGROUP
 447         {
 448                 .procname       = "sched_autogroup_enabled",
 449                 .data           = &sysctl_sched_autogroup_enabled,
 450                 .maxlen         = sizeof(unsigned int),
 451                 .mode           = 0644,
 452                 .proc_handler   = proc_dointvec_minmax,
 453                 .extra1         = &zero,
 454                 .extra2         = &one,
 455         },
 456 #endif
 457 #ifdef CONFIG_CFS_BANDWIDTH
 458         {
 459                 .procname       = "sched_cfs_bandwidth_slice_us",
 460                 .data           = &sysctl_sched_cfs_bandwidth_slice,
 461                 .maxlen         = sizeof(unsigned int),
 462                 .mode           = 0644,
 463                 .proc_handler   = proc_dointvec_minmax,
 464                 .extra1         = &one,
 465         },
 466 #endif
 467 #ifdef CONFIG_PROVE_LOCKING
 468         {
 469                 .procname       = "prove_locking",
 470                 .data           = &prove_locking,
 471                 .maxlen         = sizeof(int),
 472                 .mode           = 0644,
 473                 .proc_handler   = proc_dointvec,
 474         },
 475 #endif
 476 #ifdef CONFIG_LOCK_STAT
 477         {
 478                 .procname       = "lock_stat",
 479                 .data           = &lock_stat,
 480                 .maxlen         = sizeof(int),
 481                 .mode           = 0644,
 482                 .proc_handler   = proc_dointvec,
 483         },
 484 #endif
 485         {
 486                 .procname       = "panic",
 487                 .data           = &panic_timeout,
 488                 .maxlen         = sizeof(int),
 489                 .mode           = 0644,
 490                 .proc_handler   = proc_dointvec,
 491         },
 492 #ifdef CONFIG_COREDUMP
 493         {
 494                 .procname       = "core_uses_pid",
 495                 .data           = &core_uses_pid,
 496                 .maxlen         = sizeof(int),
 497                 .mode           = 0644,
 498                 .proc_handler   = proc_dointvec,
 499         },
 500         {
 501                 .procname       = "core_pattern",
 502                 .data           = core_pattern,
 503                 .maxlen         = CORENAME_MAX_SIZE,
 504                 .mode           = 0644,
 505                 .proc_handler   = proc_dostring_coredump,
 506         },
 507         {
 508                 .procname       = "core_pipe_limit",
 509                 .data           = &core_pipe_limit,
 510                 .maxlen         = sizeof(unsigned int),
 511                 .mode           = 0644,
 512                 .proc_handler   = proc_dointvec,
 513         },
 514 #endif
 515 #ifdef CONFIG_PROC_SYSCTL
 516         {
 517                 .procname       = "tainted",
 518                 .maxlen         = sizeof(long),
 519                 .mode           = 0644,
 520                 .proc_handler   = proc_taint,
 521         },
 522         {
 523                 .procname       = "sysctl_writes_strict",
 524                 .data           = &sysctl_writes_strict,
 525                 .maxlen         = sizeof(int),
 526                 .mode           = 0644,
 527                 .proc_handler   = proc_dointvec_minmax,
 528                 .extra1         = &neg_one,
 529                 .extra2         = &one,
 530         },
 531 #endif
 532 #ifdef CONFIG_LATENCYTOP
 533         {
 534                 .procname       = "latencytop",
 535                 .data           = &latencytop_enabled,
 536                 .maxlen         = sizeof(int),
 537                 .mode           = 0644,
 538                 .proc_handler   = sysctl_latencytop,
 539         },
 540 #endif
 541 #ifdef CONFIG_BLK_DEV_INITRD
 542         {
 543                 .procname       = "real-root-dev",
 544                 .data           = &real_root_dev,
 545                 .maxlen         = sizeof(int),
 546                 .mode           = 0644,
 547                 .proc_handler   = proc_dointvec,
 548         },
 549 #endif
 550         {
 551                 .procname       = "print-fatal-signals",
 552                 .data           = &print_fatal_signals,
 553                 .maxlen         = sizeof(int),
 554                 .mode           = 0644,
 555                 .proc_handler   = proc_dointvec,
 556         },
 557 #ifdef CONFIG_SPARC
 558         {
 559                 .procname       = "reboot-cmd",
 560                 .data           = reboot_command,
 561                 .maxlen         = 256,
 562                 .mode           = 0644,
 563                 .proc_handler   = proc_dostring,
 564         },
 565         {
 566                 .procname       = "stop-a",
 567                 .data           = &stop_a_enabled,
 568                 .maxlen         = sizeof (int),
 569                 .mode           = 0644,
 570                 .proc_handler   = proc_dointvec,
 571         },
 572         {
 573                 .procname       = "scons-poweroff",
 574                 .data           = &scons_pwroff,
 575                 .maxlen         = sizeof (int),
 576                 .mode           = 0644,
 577                 .proc_handler   = proc_dointvec,
 578         },
 579 #endif
 580 #ifdef CONFIG_SPARC64
 581         {
 582                 .procname       = "tsb-ratio",
 583                 .data           = &sysctl_tsb_ratio,
 584                 .maxlen         = sizeof (int),
 585                 .mode           = 0644,
 586                 .proc_handler   = proc_dointvec,
 587         },
 588 #endif
 589 #ifdef __hppa__
 590         {
 591                 .procname       = "soft-power",
 592                 .data           = &pwrsw_enabled,
 593                 .maxlen         = sizeof (int),
 594                 .mode           = 0644,
 595                 .proc_handler   = proc_dointvec,
 596         },
 597 #endif
 598 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
 599         {
 600                 .procname       = "unaligned-trap",
 601                 .data           = &unaligned_enabled,
 602                 .maxlen         = sizeof (int),
 603                 .mode           = 0644,
 604                 .proc_handler   = proc_dointvec,
 605         },
 606 #endif
 607         {
 608                 .procname       = "ctrl-alt-del",
 609                 .data           = &C_A_D,
 610                 .maxlen         = sizeof(int),
 611                 .mode           = 0644,
 612                 .proc_handler   = proc_dointvec,
 613         },
 614 #ifdef CONFIG_FUNCTION_TRACER
 615         {
 616                 .procname       = "ftrace_enabled",
 617                 .data           = &ftrace_enabled,
 618                 .maxlen         = sizeof(int),
 619                 .mode           = 0644,
 620                 .proc_handler   = ftrace_enable_sysctl,
 621         },
 622 #endif
 623 #ifdef CONFIG_STACK_TRACER
 624         {
 625                 .procname       = "stack_tracer_enabled",
 626                 .data           = &stack_tracer_enabled,
 627                 .maxlen         = sizeof(int),
 628                 .mode           = 0644,
 629                 .proc_handler   = stack_trace_sysctl,
 630         },
 631 #endif
 632 #ifdef CONFIG_TRACING
 633         {
 634                 .procname       = "ftrace_dump_on_oops",
 635                 .data           = &ftrace_dump_on_oops,
 636                 .maxlen         = sizeof(int),
 637                 .mode           = 0644,
 638                 .proc_handler   = proc_dointvec,
 639         },
 640         {
 641                 .procname       = "traceoff_on_warning",
 642                 .data           = &__disable_trace_on_warning,
 643                 .maxlen         = sizeof(__disable_trace_on_warning),
 644                 .mode           = 0644,
 645                 .proc_handler   = proc_dointvec,
 646         },
 647         {
 648                 .procname       = "tracepoint_printk",
 649                 .data           = &tracepoint_printk,
 650                 .maxlen         = sizeof(tracepoint_printk),
 651                 .mode           = 0644,
 652                 .proc_handler   = tracepoint_printk_sysctl,
 653         },
 654 #endif
 655 #ifdef CONFIG_KEXEC_CORE
 656         {
 657                 .procname       = "kexec_load_disabled",
 658                 .data           = &kexec_load_disabled,
 659                 .maxlen         = sizeof(int),
 660                 .mode           = 0644,
 661                 /* only handle a transition from default "0" to "1" */
 662                 .proc_handler   = proc_dointvec_minmax,
 663                 .extra1         = &one,
 664                 .extra2         = &one,
 665         },
 666 #endif
 667 #ifdef CONFIG_MODULES
 668         {
 669                 .procname       = "modprobe",
 670                 .data           = &modprobe_path,
 671                 .maxlen         = KMOD_PATH_LEN,
 672                 .mode           = 0644,
 673                 .proc_handler   = proc_dostring,
 674         },
 675         {
 676                 .procname       = "modules_disabled",
 677                 .data           = &modules_disabled,
 678                 .maxlen         = sizeof(int),
 679                 .mode           = 0644,
 680                 /* only handle a transition from default "0" to "1" */
 681                 .proc_handler   = proc_dointvec_minmax,
 682                 .extra1         = &one,
 683                 .extra2         = &one,
 684         },
 685 #endif
 686 #ifdef CONFIG_UEVENT_HELPER
 687         {
 688                 .procname       = "hotplug",
 689                 .data           = &uevent_helper,
 690                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 691                 .mode           = 0644,
 692                 .proc_handler   = proc_dostring,
 693         },
 694 #endif
 695 #ifdef CONFIG_CHR_DEV_SG
 696         {
 697                 .procname       = "sg-big-buff",
 698                 .data           = &sg_big_buff,
 699                 .maxlen         = sizeof (int),
 700                 .mode           = 0444,
 701                 .proc_handler   = proc_dointvec,
 702         },
 703 #endif
 704 #ifdef CONFIG_BSD_PROCESS_ACCT
 705         {
 706                 .procname       = "acct",
 707                 .data           = &acct_parm,
 708                 .maxlen         = 3*sizeof(int),
 709                 .mode           = 0644,
 710                 .proc_handler   = proc_dointvec,
 711         },
 712 #endif
 713 #ifdef CONFIG_MAGIC_SYSRQ
 714         {
 715                 .procname       = "sysrq",
 716                 .data           = &__sysrq_enabled,
 717                 .maxlen         = sizeof (int),
 718                 .mode           = 0644,
 719                 .proc_handler   = sysrq_sysctl_handler,
 720         },
 721 #endif
 722 #ifdef CONFIG_PROC_SYSCTL
 723         {
 724                 .procname       = "cad_pid",
 725                 .data           = NULL,
 726                 .maxlen         = sizeof (int),
 727                 .mode           = 0600,
 728                 .proc_handler   = proc_do_cad_pid,
 729         },
 730 #endif
 731         {
 732                 .procname       = "threads-max",
 733                 .data           = NULL,
 734                 .maxlen         = sizeof(int),
 735                 .mode           = 0644,
 736                 .proc_handler   = sysctl_max_threads,
 737         },
 738         {
 739                 .procname       = "random",
 740                 .mode           = 0555,
 741                 .child          = random_table,
 742         },
 743         {
 744                 .procname       = "usermodehelper",
 745                 .mode           = 0555,
 746                 .child          = usermodehelper_table,
 747         },
 748         {
 749                 .procname       = "overflowuid",
 750                 .data           = &overflowuid,
 751                 .maxlen         = sizeof(int),
 752                 .mode           = 0644,
 753                 .proc_handler   = proc_dointvec_minmax,
 754                 .extra1         = &minolduid,
 755                 .extra2         = &maxolduid,
 756         },
 757         {
 758                 .procname       = "overflowgid",
 759                 .data           = &overflowgid,
 760                 .maxlen         = sizeof(int),
 761                 .mode           = 0644,
 762                 .proc_handler   = proc_dointvec_minmax,
 763                 .extra1         = &minolduid,
 764                 .extra2         = &maxolduid,
 765         },
 766 #ifdef CONFIG_S390
 767 #ifdef CONFIG_MATHEMU
 768         {
 769                 .procname       = "ieee_emulation_warnings",
 770                 .data           = &sysctl_ieee_emulation_warnings,
 771                 .maxlen         = sizeof(int),
 772                 .mode           = 0644,
 773                 .proc_handler   = proc_dointvec,
 774         },
 775 #endif
 776         {
 777                 .procname       = "userprocess_debug",
 778                 .data           = &show_unhandled_signals,
 779                 .maxlen         = sizeof(int),
 780                 .mode           = 0644,
 781                 .proc_handler   = proc_dointvec,
 782         },
 783 #endif
 784         {
 785                 .procname       = "pid_max",
 786                 .data           = &pid_max,
 787                 .maxlen         = sizeof (int),
 788                 .mode           = 0644,
 789                 .proc_handler   = proc_dointvec_minmax,
 790                 .extra1         = &pid_max_min,
 791                 .extra2         = &pid_max_max,
 792         },
 793         {
 794                 .procname       = "panic_on_oops",
 795                 .data           = &panic_on_oops,
 796                 .maxlen         = sizeof(int),
 797                 .mode           = 0644,
 798                 .proc_handler   = proc_dointvec,
 799         },
 800 #if defined CONFIG_PRINTK
 801         {
 802                 .procname       = "printk",
 803                 .data           = &console_loglevel,
 804                 .maxlen         = 4*sizeof(int),
 805                 .mode           = 0644,
 806                 .proc_handler   = proc_dointvec,
 807         },
 808         {
 809                 .procname       = "printk_ratelimit",
 810                 .data           = &printk_ratelimit_state.interval,
 811                 .maxlen         = sizeof(int),
 812                 .mode           = 0644,
 813                 .proc_handler   = proc_dointvec_jiffies,
 814         },
 815         {
 816                 .procname       = "printk_ratelimit_burst",
 817                 .data           = &printk_ratelimit_state.burst,
 818                 .maxlen         = sizeof(int),
 819                 .mode           = 0644,
 820                 .proc_handler   = proc_dointvec,
 821         },
 822         {
 823                 .procname       = "printk_delay",
 824                 .data           = &printk_delay_msec,
 825                 .maxlen         = sizeof(int),
 826                 .mode           = 0644,
 827                 .proc_handler   = proc_dointvec_minmax,
 828                 .extra1         = &zero,
 829                 .extra2         = &ten_thousand,
 830         },
 831         {
 832                 .procname       = "printk_devkmsg",
 833                 .data           = devkmsg_log_str,
 834                 .maxlen         = DEVKMSG_STR_MAX_SIZE,
 835                 .mode           = 0644,
 836                 .proc_handler   = devkmsg_sysctl_set_loglvl,
 837         },
 838         {
 839                 .procname       = "dmesg_restrict",
 840                 .data           = &dmesg_restrict,
 841                 .maxlen         = sizeof(int),
 842                 .mode           = 0644,
 843                 .proc_handler   = proc_dointvec_minmax_sysadmin,
 844                 .extra1         = &zero,
 845                 .extra2         = &one,
 846         },
 847         {
 848                 .procname       = "kptr_restrict",
 849                 .data           = &kptr_restrict,
 850                 .maxlen         = sizeof(int),
 851                 .mode           = 0644,
 852                 .proc_handler   = proc_dointvec_minmax_sysadmin,
 853                 .extra1         = &zero,
 854                 .extra2         = &two,
 855         },
 856 #endif
 857         {
 858                 .procname       = "ngroups_max",
 859                 .data           = &ngroups_max,
 860                 .maxlen         = sizeof (int),
 861                 .mode           = 0444,
 862                 .proc_handler   = proc_dointvec,
 863         },
 864         {
 865                 .procname       = "cap_last_cap",
 866                 .data           = (void *)&cap_last_cap,
 867                 .maxlen         = sizeof(int),
 868                 .mode           = 0444,
 869                 .proc_handler   = proc_dointvec,
 870         },
 871 #if defined(CONFIG_LOCKUP_DETECTOR)
 872         {
 873                 .procname       = "watchdog",
 874                 .data           = &watchdog_user_enabled,
 875                 .maxlen         = sizeof (int),
 876                 .mode           = 0644,
 877                 .proc_handler   = proc_watchdog,
 878                 .extra1         = &zero,
 879                 .extra2         = &one,
 880         },
 881         {
 882                 .procname       = "watchdog_thresh",
 883                 .data           = &watchdog_thresh,
 884                 .maxlen         = sizeof(int),
 885                 .mode           = 0644,
 886                 .proc_handler   = proc_watchdog_thresh,
 887                 .extra1         = &zero,
 888                 .extra2         = &sixty,
 889         },
 890         {
 891                 .procname       = "nmi_watchdog",
 892                 .data           = &nmi_watchdog_enabled,
 893                 .maxlen         = sizeof (int),
 894                 .mode           = 0644,
 895                 .proc_handler   = proc_nmi_watchdog,
 896                 .extra1         = &zero,
 897 #if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)
 898                 .extra2         = &one,
 899 #else
 900                 .extra2         = &zero,
 901 #endif
 902         },
 903         {
 904                 .procname       = "watchdog_cpumask",
 905                 .data           = &watchdog_cpumask_bits,
 906                 .maxlen         = NR_CPUS,
 907                 .mode           = 0644,
 908                 .proc_handler   = proc_watchdog_cpumask,
 909         },
 910 #ifdef CONFIG_SOFTLOCKUP_DETECTOR
 911         {
 912                 .procname       = "soft_watchdog",
 913                 .data           = &soft_watchdog_enabled,
 914                 .maxlen         = sizeof (int),
 915                 .mode           = 0644,
 916                 .proc_handler   = proc_soft_watchdog,
 917                 .extra1         = &zero,
 918                 .extra2         = &one,
 919         },
 920         {
 921                 .procname       = "softlockup_panic",
 922                 .data           = &softlockup_panic,
 923                 .maxlen         = sizeof(int),
 924                 .mode           = 0644,
 925                 .proc_handler   = proc_dointvec_minmax,
 926                 .extra1         = &zero,
 927                 .extra2         = &one,
 928         },
 929 #ifdef CONFIG_SMP
 930         {
 931                 .procname       = "softlockup_all_cpu_backtrace",
 932                 .data           = &sysctl_softlockup_all_cpu_backtrace,
 933                 .maxlen         = sizeof(int),
 934                 .mode           = 0644,
 935                 .proc_handler   = proc_dointvec_minmax,
 936                 .extra1         = &zero,
 937                 .extra2         = &one,
 938         },
 939 #endif /* CONFIG_SMP */
 940 #endif
 941 #ifdef CONFIG_HARDLOCKUP_DETECTOR
 942         {
 943                 .procname       = "hardlockup_panic",
 944                 .data           = &hardlockup_panic,
 945                 .maxlen         = sizeof(int),
 946                 .mode           = 0644,
 947                 .proc_handler   = proc_dointvec_minmax,
 948                 .extra1         = &zero,
 949                 .extra2         = &one,
 950         },
 951 #ifdef CONFIG_SMP
 952         {
 953                 .procname       = "hardlockup_all_cpu_backtrace",
 954                 .data           = &sysctl_hardlockup_all_cpu_backtrace,
 955                 .maxlen         = sizeof(int),
 956                 .mode           = 0644,
 957                 .proc_handler   = proc_dointvec_minmax,
 958                 .extra1         = &zero,
 959                 .extra2         = &one,
 960         },
 961 #endif /* CONFIG_SMP */
 962 #endif
 963 #endif
 964
 965 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 966         {
 967                 .procname       = "unknown_nmi_panic",
 968                 .data           = &unknown_nmi_panic,
 969                 .maxlen         = sizeof (int),
 970                 .mode           = 0644,
 971                 .proc_handler   = proc_dointvec,
 972         },
 973 #endif
 974 #if defined(CONFIG_X86)
 975         {
 976                 .procname       = "panic_on_unrecovered_nmi",
 977                 .data           = &panic_on_unrecovered_nmi,
 978                 .maxlen         = sizeof(int),
 979                 .mode           = 0644,
 980                 .proc_handler   = proc_dointvec,
 981         },
 982         {
 983                 .procname       = "panic_on_io_nmi",
 984                 .data           = &panic_on_io_nmi,
 985                 .maxlen         = sizeof(int),
 986                 .mode           = 0644,
 987                 .proc_handler   = proc_dointvec,
 988         },
 989 #ifdef CONFIG_DEBUG_STACKOVERFLOW
 990         {
 991                 .procname       = "panic_on_stackoverflow",
 992                 .data           = &sysctl_panic_on_stackoverflow,
 993                 .maxlen         = sizeof(int),
 994                 .mode           = 0644,
 995                 .proc_handler   = proc_dointvec,
 996         },
 997 #endif
 998         {
 999                 .procname       = "bootloader_type",
1000                 .data           = &bootloader_type,
1001                 .maxlen         = sizeof (int),
1002                 .mode           = 0444,
1003                 .proc_handler   = proc_dointvec,
1004         },
1005         {
1006                 .procname       = "bootloader_version",
1007                 .data           = &bootloader_version,
1008                 .maxlen         = sizeof (int),
1009                 .mode           = 0444,
1010                 .proc_handler   = proc_dointvec,
1011         },
1012         {
1013                 .procname       = "io_delay_type",
1014                 .data           = &io_delay_type,
1015                 .maxlen         = sizeof(int),
1016                 .mode           = 0644,
1017                 .proc_handler   = proc_dointvec,
1018         },
1019 #endif
1020 #if defined(CONFIG_MMU)
1021         {
1022                 .procname       = "randomize_va_space",
1023                 .data           = &randomize_va_space,
1024                 .maxlen         = sizeof(int),
1025                 .mode           = 0644,
1026                 .proc_handler   = proc_dointvec,
1027         },
1028 #endif
1029 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1030         {
1031                 .procname       = "spin_retry",
1032                 .data           = &spin_retry,
1033                 .maxlen         = sizeof (int),
1034                 .mode           = 0644,
1035                 .proc_handler   = proc_dointvec,
1036         },
1037 #endif
1038 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1039         {
1040                 .procname       = "acpi_video_flags",
1041                 .data           = &acpi_realmode_flags,
1042                 .maxlen         = sizeof (unsigned long),
1043                 .mode           = 0644,
1044                 .proc_handler   = proc_doulongvec_minmax,
1045         },
1046 #endif
1047 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1048         {
1049                 .procname       = "ignore-unaligned-usertrap",
1050                 .data           = &no_unaligned_warning,
1051                 .maxlen         = sizeof (int),
1052                 .mode           = 0644,
1053                 .proc_handler   = proc_dointvec,
1054         },
1055 #endif
1056 #ifdef CONFIG_IA64
1057         {
1058                 .procname       = "unaligned-dump-stack",
1059                 .data           = &unaligned_dump_stack,
1060                 .maxlen         = sizeof (int),
1061                 .mode           = 0644,
1062                 .proc_handler   = proc_dointvec,
1063         },
1064 #endif
1065 #ifdef CONFIG_DETECT_HUNG_TASK
1066         {
1067                 .procname       = "hung_task_panic",
1068                 .data           = &sysctl_hung_task_panic,
1069                 .maxlen         = sizeof(int),
1070                 .mode           = 0644,
1071                 .proc_handler   = proc_dointvec_minmax,
1072                 .extra1         = &zero,
1073                 .extra2         = &one,
1074         },
1075         {
1076                 .procname       = "hung_task_check_count",
1077                 .data           = &sysctl_hung_task_check_count,
1078                 .maxlen         = sizeof(int),
1079                 .mode           = 0644,
1080                 .proc_handler   = proc_dointvec_minmax,
1081                 .extra1         = &zero,
1082         },
1083         {
1084                 .procname       = "hung_task_timeout_secs",
1085                 .data           = &sysctl_hung_task_timeout_secs,
1086                 .maxlen         = sizeof(unsigned long),
1087                 .mode           = 0644,
1088                 .proc_handler   = proc_dohung_task_timeout_secs,
1089                 .extra2         = &hung_task_timeout_max,
1090         },
1091         {
1092                 .procname       = "hung_task_warnings",
1093                 .data           = &sysctl_hung_task_warnings,
1094                 .maxlen         = sizeof(int),
1095                 .mode           = 0644,
1096                 .proc_handler   = proc_dointvec_minmax,
1097                 .extra1         = &neg_one,
1098         },
1099 #endif
1100 #ifdef CONFIG_RT_MUTEXES
1101         {
1102                 .procname       = "max_lock_depth",
1103                 .data           = &max_lock_depth,
1104                 .maxlen         = sizeof(int),
1105                 .mode           = 0644,
1106                 .proc_handler   = proc_dointvec,
1107         },
1108 #endif
1109         {
1110                 .procname       = "poweroff_cmd",
1111                 .data           = &poweroff_cmd,
1112                 .maxlen         = POWEROFF_CMD_PATH_LEN,
1113                 .mode           = 0644,
1114                 .proc_handler   = proc_dostring,
1115         },
1116 #ifdef CONFIG_KEYS
1117         {
1118                 .procname       = "keys",
1119                 .mode           = 0555,
1120                 .child          = key_sysctls,
1121         },
1122 #endif
1123 #ifdef CONFIG_PERF_EVENTS
1124         /*
1125          * User-space scripts rely on the existence of this file
1126          * as a feature check for perf_events being enabled.
1127          *
1128          * So it's an ABI, do not remove!
1129          */
1130         {
1131                 .procname       = "perf_event_paranoid",
1132                 .data           = &sysctl_perf_event_paranoid,
1133                 .maxlen         = sizeof(sysctl_perf_event_paranoid),
1134                 .mode           = 0644,
1135                 .proc_handler   = proc_dointvec,
1136         },
1137         {
1138                 .procname       = "perf_event_mlock_kb",
1139                 .data           = &sysctl_perf_event_mlock,
1140                 .maxlen         = sizeof(sysctl_perf_event_mlock),
1141                 .mode           = 0644,
1142                 .proc_handler   = proc_dointvec,
1143         },
1144         {
1145                 .procname       = "perf_event_max_sample_rate",
1146                 .data           = &sysctl_perf_event_sample_rate,
1147                 .maxlen         = sizeof(sysctl_perf_event_sample_rate),
1148                 .mode           = 0644,
1149                 .proc_handler   = perf_proc_update_handler,
1150                 .extra1         = &one,
1151         },
1152         {
1153                 .procname       = "perf_cpu_time_max_percent",
1154                 .data           = &sysctl_perf_cpu_time_max_percent,
1155                 .maxlen         = sizeof(sysctl_perf_cpu_time_max_percent),
1156                 .mode           = 0644,
1157                 .proc_handler   = perf_cpu_time_max_percent_handler,
1158                 .extra1         = &zero,
1159                 .extra2         = &one_hundred,
1160         },
1161         {
1162                 .procname       = "perf_event_max_stack",
1163                 .data           = &sysctl_perf_event_max_stack,
1164                 .maxlen         = sizeof(sysctl_perf_event_max_stack),
1165                 .mode           = 0644,
1166                 .proc_handler   = perf_event_max_stack_handler,
1167                 .extra1         = &zero,
1168                 .extra2         = &six_hundred_forty_kb,
1169         },
1170         {
1171                 .procname       = "perf_event_max_contexts_per_stack",
1172                 .data           = &sysctl_perf_event_max_contexts_per_stack,
1173                 .maxlen         = sizeof(sysctl_perf_event_max_contexts_per_stack),
1174                 .mode           = 0644,
1175                 .proc_handler   = perf_event_max_stack_handler,
1176                 .extra1         = &zero,
1177                 .extra2         = &one_thousand,
1178         },
1179 #endif
1180 #ifdef CONFIG_KMEMCHECK
1181         {
1182                 .procname       = "kmemcheck",
1183                 .data           = &kmemcheck_enabled,
1184                 .maxlen         = sizeof(int),
1185                 .mode           = 0644,
1186                 .proc_handler   = proc_dointvec,
1187         },
1188 #endif
1189         {
1190                 .procname       = "panic_on_warn",
1191                 .data           = &panic_on_warn,
1192                 .maxlen         = sizeof(int),
1193                 .mode           = 0644,
1194                 .proc_handler   = proc_dointvec_minmax,
1195                 .extra1         = &zero,
1196                 .extra2         = &one,
1197         },
1198 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1199         {
1200                 .procname       = "timer_migration",
1201                 .data           = &sysctl_timer_migration,
1202                 .maxlen         = sizeof(unsigned int),
1203                 .mode           = 0644,
1204                 .proc_handler   = timer_migration_handler,
1205                 .extra1         = &zero,
1206                 .extra2         = &one,
1207         },
1208 #endif
1209 #ifdef CONFIG_BPF_SYSCALL
1210         {
1211                 .procname       = "unprivileged_bpf_disabled",
1212                 .data           = &sysctl_unprivileged_bpf_disabled,
1213                 .maxlen         = sizeof(sysctl_unprivileged_bpf_disabled),
1214                 .mode           = 0644,
1215                 /* only handle a transition from default "0" to "1" */
1216                 .proc_handler   = proc_dointvec_minmax,
1217                 .extra1         = &one,
1218                 .extra2         = &one,
1219         },
1220 #endif
1221 #if defined(CONFIG_TREE_RCU) || defined(CONFIG_PREEMPT_RCU)
1222         {
1223                 .procname       = "panic_on_rcu_stall",
1224                 .data           = &sysctl_panic_on_rcu_stall,
1225                 .maxlen         = sizeof(sysctl_panic_on_rcu_stall),
1226                 .mode           = 0644,
1227                 .proc_handler   = proc_dointvec_minmax,
1228                 .extra1         = &zero,
1229                 .extra2         = &one,
1230         },
1231 #endif
1232         { }
1233 };
1234
1235 static struct ctl_table vm_table[] = {
1236         {
1237                 .procname       = "overcommit_memory",
1238                 .data           = &sysctl_overcommit_memory,
1239                 .maxlen         = sizeof(sysctl_overcommit_memory),
1240                 .mode           = 0644,
1241                 .proc_handler   = proc_dointvec_minmax,
1242                 .extra1         = &zero,
1243                 .extra2         = &two,
1244         },
1245         {
1246                 .procname       = "panic_on_oom",
1247                 .data           = &sysctl_panic_on_oom,
1248                 .maxlen         = sizeof(sysctl_panic_on_oom),
1249                 .mode           = 0644,
1250                 .proc_handler   = proc_dointvec_minmax,
1251                 .extra1         = &zero,
1252                 .extra2         = &two,
1253         },
1254         {
1255                 .procname       = "oom_kill_allocating_task",
1256                 .data           = &sysctl_oom_kill_allocating_task,
1257                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
1258                 .mode           = 0644,
1259                 .proc_handler   = proc_dointvec,
1260         },
1261         {
1262                 .procname       = "oom_dump_tasks",
1263                 .data           = &sysctl_oom_dump_tasks,
1264                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
1265                 .mode           = 0644,
1266                 .proc_handler   = proc_dointvec,
1267         },
1268         {
1269                 .procname       = "overcommit_ratio",
1270                 .data           = &sysctl_overcommit_ratio,
1271                 .maxlen         = sizeof(sysctl_overcommit_ratio),
1272                 .mode           = 0644,
1273                 .proc_handler   = overcommit_ratio_handler,
1274         },
1275         {
1276                 .procname       = "overcommit_kbytes",
1277                 .data           = &sysctl_overcommit_kbytes,
1278                 .maxlen         = sizeof(sysctl_overcommit_kbytes),
1279                 .mode           = 0644,
1280                 .proc_handler   = overcommit_kbytes_handler,
1281         },
1282         {
1283                 .procname       = "page-cluster",
1284                 .data           = &page_cluster,
1285                 .maxlen         = sizeof(int),
1286                 .mode           = 0644,
1287                 .proc_handler   = proc_dointvec_minmax,
1288                 .extra1         = &zero,
1289         },
1290         {
1291                 .procname       = "dirty_background_ratio",
1292                 .data           = &dirty_background_ratio,
1293                 .maxlen         = sizeof(dirty_background_ratio),
1294                 .mode           = 0644,
1295                 .proc_handler   = dirty_background_ratio_handler,
1296                 .extra1         = &zero,
1297                 .extra2         = &one_hundred,
1298         },
1299         {
1300                 .procname       = "dirty_background_bytes",
1301                 .data           = &dirty_background_bytes,
1302                 .maxlen         = sizeof(dirty_background_bytes),
1303                 .mode           = 0644,
1304                 .proc_handler   = dirty_background_bytes_handler,
1305                 .extra1         = &one_ul,
1306         },
1307         {
1308                 .procname       = "dirty_ratio",
1309                 .data           = &vm_dirty_ratio,
1310                 .maxlen         = sizeof(vm_dirty_ratio),
1311                 .mode           = 0644,
1312                 .proc_handler   = dirty_ratio_handler,
1313                 .extra1         = &zero,
1314                 .extra2         = &one_hundred,
1315         },
1316         {
1317                 .procname       = "dirty_bytes",
1318                 .data           = &vm_dirty_bytes,
1319                 .maxlen         = sizeof(vm_dirty_bytes),
1320                 .mode           = 0644,
1321                 .proc_handler   = dirty_bytes_handler,
1322                 .extra1         = &dirty_bytes_min,
1323         },
1324         {
1325                 .procname       = "dirty_writeback_centisecs",
1326                 .data           = &dirty_writeback_interval,
1327                 .maxlen         = sizeof(dirty_writeback_interval),
1328                 .mode           = 0644,
1329                 .proc_handler   = dirty_writeback_centisecs_handler,
1330         },
1331         {
1332                 .procname       = "dirty_expire_centisecs",
1333                 .data           = &dirty_expire_interval,
1334                 .maxlen         = sizeof(dirty_expire_interval),
1335                 .mode           = 0644,
1336                 .proc_handler   = proc_dointvec_minmax,
1337                 .extra1         = &zero,
1338         },
1339         {
1340                 .procname       = "dirtytime_expire_seconds",
1341                 .data           = &dirtytime_expire_interval,
1342                 .maxlen         = sizeof(dirty_expire_interval),
1343                 .mode           = 0644,
1344                 .proc_handler   = dirtytime_interval_handler,
1345                 .extra1         = &zero,
1346         },
1347         {
1348                 .procname       = "nr_pdflush_threads",
1349                 .mode           = 0444 /* read-only */,
1350                 .proc_handler   = pdflush_proc_obsolete,
1351         },
1352         {
1353                 .procname       = "swappiness",
1354                 .data           = &vm_swappiness,
1355                 .maxlen         = sizeof(vm_swappiness),
1356                 .mode           = 0644,
1357                 .proc_handler   = proc_dointvec_minmax,
1358                 .extra1         = &zero,
1359                 .extra2         = &one_hundred,
1360         },
1361 #ifdef CONFIG_HUGETLB_PAGE
1362         {
1363                 .procname       = "nr_hugepages",
1364                 .data           = NULL,
1365                 .maxlen         = sizeof(unsigned long),
1366                 .mode           = 0644,
1367                 .proc_handler   = hugetlb_sysctl_handler,
1368         },
1369 #ifdef CONFIG_NUMA
1370         {
1371                 .procname       = "nr_hugepages_mempolicy",
1372                 .data           = NULL,
1373                 .maxlen         = sizeof(unsigned long),
1374                 .mode           = 0644,
1375                 .proc_handler   = &hugetlb_mempolicy_sysctl_handler,
1376         },
1377 #endif
1378          {
1379                 .procname       = "hugetlb_shm_group",
1380                 .data           = &sysctl_hugetlb_shm_group,
1381                 .maxlen         = sizeof(gid_t),
1382                 .mode           = 0644,
1383                 .proc_handler   = proc_dointvec,
1384          },
1385          {
1386                 .procname       = "hugepages_treat_as_movable",
1387                 .data           = &hugepages_treat_as_movable,
1388                 .maxlen         = sizeof(int),
1389                 .mode           = 0644,
1390                 .proc_handler   = proc_dointvec,
1391         },
1392         {
1393                 .procname       = "nr_overcommit_hugepages",
1394                 .data           = NULL,
1395                 .maxlen         = sizeof(unsigned long),
1396                 .mode           = 0644,
1397                 .proc_handler   = hugetlb_overcommit_handler,
1398         },
1399 #endif
1400         {
1401                 .procname       = "lowmem_reserve_ratio",
1402                 .data           = &sysctl_lowmem_reserve_ratio,
1403                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1404                 .mode           = 0644,
1405                 .proc_handler   = lowmem_reserve_ratio_sysctl_handler,
1406         },
1407         {
1408                 .procname       = "drop_caches",
1409                 .data           = &sysctl_drop_caches,
1410                 .maxlen         = sizeof(int),
1411                 .mode           = 0644,
1412                 .proc_handler   = drop_caches_sysctl_handler,
1413                 .extra1         = &one,
1414                 .extra2         = &four,
1415         },
1416 #ifdef CONFIG_COMPACTION
1417         {
1418                 .procname       = "compact_memory",
1419                 .data           = &sysctl_compact_memory,
1420                 .maxlen         = sizeof(int),
1421                 .mode           = 0200,
1422                 .proc_handler   = sysctl_compaction_handler,
1423         },
1424         {
1425                 .procname       = "extfrag_threshold",
1426                 .data           = &sysctl_extfrag_threshold,
1427                 .maxlen         = sizeof(int),
1428                 .mode           = 0644,
1429                 .proc_handler   = sysctl_extfrag_handler,
1430                 .extra1         = &min_extfrag_threshold,
1431                 .extra2         = &max_extfrag_threshold,
1432         },
1433         {
1434                 .procname       = "compact_unevictable_allowed",
1435                 .data           = &sysctl_compact_unevictable_allowed,
1436                 .maxlen         = sizeof(int),
1437                 .mode           = 0644,
1438                 .proc_handler   = proc_dointvec,
1439                 .extra1         = &zero,
1440                 .extra2         = &one,
1441         },
1442
1443 #endif /* CONFIG_COMPACTION */
1444         {
1445                 .procname       = "min_free_kbytes",
1446                 .data           = &min_free_kbytes,
1447                 .maxlen         = sizeof(min_free_kbytes),
1448                 .mode           = 0644,
1449                 .proc_handler   = min_free_kbytes_sysctl_handler,
1450                 .extra1         = &zero,
1451         },
1452         {
1453                 .procname       = "watermark_scale_factor",
1454                 .data           = &watermark_scale_factor,
1455                 .maxlen         = sizeof(watermark_scale_factor),
1456                 .mode           = 0644,
1457                 .proc_handler   = watermark_scale_factor_sysctl_handler,
1458                 .extra1         = &one,
1459                 .extra2         = &one_thousand,
1460         },
1461         {
1462                 .procname       = "percpu_pagelist_fraction",
1463                 .data           = &percpu_pagelist_fraction,
1464                 .maxlen         = sizeof(percpu_pagelist_fraction),
1465                 .mode           = 0644,
1466                 .proc_handler   = percpu_pagelist_fraction_sysctl_handler,
1467                 .extra1         = &zero,
1468         },
1469 #ifdef CONFIG_MMU
1470         {
1471                 .procname       = "max_map_count",
1472                 .data           = &sysctl_max_map_count,
1473                 .maxlen         = sizeof(sysctl_max_map_count),
1474                 .mode           = 0644,
1475                 .proc_handler   = proc_dointvec_minmax,
1476                 .extra1         = &zero,
1477         },
1478 #else
1479         {
1480                 .procname       = "nr_trim_pages",
1481                 .data           = &sysctl_nr_trim_pages,
1482                 .maxlen         = sizeof(sysctl_nr_trim_pages),
1483                 .mode           = 0644,
1484                 .proc_handler   = proc_dointvec_minmax,
1485                 .extra1         = &zero,
1486         },
1487 #endif
1488         {
1489                 .procname       = "laptop_mode",
1490                 .data           = &laptop_mode,
1491                 .maxlen         = sizeof(laptop_mode),
1492                 .mode           = 0644,
1493                 .proc_handler   = proc_dointvec_jiffies,
1494         },
1495         {
1496                 .procname       = "block_dump",
1497                 .data           = &block_dump,
1498                 .maxlen         = sizeof(block_dump),
1499                 .mode           = 0644,
1500                 .proc_handler   = proc_dointvec,
1501                 .extra1         = &zero,
1502         },
1503         {
1504                 .procname       = "vfs_cache_pressure",
1505                 .data           = &sysctl_vfs_cache_pressure,
1506                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1507                 .mode           = 0644,
1508                 .proc_handler   = proc_dointvec,
1509                 .extra1         = &zero,
1510         },
1511 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1512         {
1513                 .procname       = "legacy_va_layout",
1514                 .data           = &sysctl_legacy_va_layout,
1515                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1516                 .mode           = 0644,
1517                 .proc_handler   = proc_dointvec,
1518                 .extra1         = &zero,
1519         },
1520 #endif
1521 #ifdef CONFIG_NUMA
1522         {
1523                 .procname       = "zone_reclaim_mode",
1524                 .data           = &node_reclaim_mode,
1525                 .maxlen         = sizeof(node_reclaim_mode),
1526                 .mode           = 0644,
1527                 .proc_handler   = proc_dointvec,
1528                 .extra1         = &zero,
1529         },
1530         {
1531                 .procname       = "min_unmapped_ratio",
1532                 .data           = &sysctl_min_unmapped_ratio,
1533                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1534                 .mode           = 0644,
1535                 .proc_handler   = sysctl_min_unmapped_ratio_sysctl_handler,
1536                 .extra1         = &zero,
1537                 .extra2         = &one_hundred,
1538         },
1539         {
1540                 .procname       = "min_slab_ratio",
1541                 .data           = &sysctl_min_slab_ratio,
1542                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1543                 .mode           = 0644,
1544                 .proc_handler   = sysctl_min_slab_ratio_sysctl_handler,
1545                 .extra1         = &zero,
1546                 .extra2         = &one_hundred,
1547         },
1548 #endif
1549 #ifdef CONFIG_SMP
1550         {
1551                 .procname       = "stat_interval",
1552                 .data           = &sysctl_stat_interval,
1553                 .maxlen         = sizeof(sysctl_stat_interval),
1554                 .mode           = 0644,
1555                 .proc_handler   = proc_dointvec_jiffies,
1556         },
1557         {
1558                 .procname       = "stat_refresh",
1559                 .data           = NULL,
1560                 .maxlen         = 0,
1561                 .mode           = 0600,
1562                 .proc_handler   = vmstat_refresh,
1563         },
1564 #endif
1565 #ifdef CONFIG_MMU
1566         {
1567                 .procname       = "mmap_min_addr",
1568                 .data           = &dac_mmap_min_addr,
1569                 .maxlen         = sizeof(unsigned long),
1570                 .mode           = 0644,
1571                 .proc_handler   = mmap_min_addr_handler,
1572         },
1573 #endif
1574 #ifdef CONFIG_NUMA
1575         {
1576                 .procname       = "numa_zonelist_order",
1577                 .data           = &numa_zonelist_order,
1578                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1579                 .mode           = 0644,
1580                 .proc_handler   = numa_zonelist_order_handler,
1581         },
1582 #endif
1583 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1584    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1585         {
1586                 .procname       = "vdso_enabled",
1587 #ifdef CONFIG_X86_32
1588                 .data           = &vdso32_enabled,
1589                 .maxlen         = sizeof(vdso32_enabled),
1590 #else
1591                 .data           = &vdso_enabled,
1592                 .maxlen         = sizeof(vdso_enabled),
1593 #endif
1594                 .mode           = 0644,
1595                 .proc_handler   = proc_dointvec,
1596                 .extra1         = &zero,
1597         },
1598 #endif
1599 #ifdef CONFIG_HIGHMEM
1600         {
1601                 .procname       = "highmem_is_dirtyable",
1602                 .data           = &vm_highmem_is_dirtyable,
1603                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1604                 .mode           = 0644,
1605                 .proc_handler   = proc_dointvec_minmax,
1606                 .extra1         = &zero,
1607                 .extra2         = &one,
1608         },
1609 #endif
1610 #ifdef CONFIG_MEMORY_FAILURE
1611         {
1612                 .procname       = "memory_failure_early_kill",
1613                 .data           = &sysctl_memory_failure_early_kill,
1614                 .maxlen         = sizeof(sysctl_memory_failure_early_kill),
1615                 .mode           = 0644,
1616                 .proc_handler   = proc_dointvec_minmax,
1617                 .extra1         = &zero,
1618                 .extra2         = &one,
1619         },
1620         {
1621                 .procname       = "memory_failure_recovery",
1622                 .data           = &sysctl_memory_failure_recovery,
1623                 .maxlen         = sizeof(sysctl_memory_failure_recovery),
1624                 .mode           = 0644,
1625                 .proc_handler   = proc_dointvec_minmax,
1626                 .extra1         = &zero,
1627                 .extra2         = &one,
1628         },
1629 #endif
1630         {
1631                 .procname       = "user_reserve_kbytes",
1632                 .data           = &sysctl_user_reserve_kbytes,
1633                 .maxlen         = sizeof(sysctl_user_reserve_kbytes),
1634                 .mode           = 0644,
1635                 .proc_handler   = proc_doulongvec_minmax,
1636         },
1637         {
1638                 .procname       = "admin_reserve_kbytes",
1639                 .data           = &sysctl_admin_reserve_kbytes,
1640                 .maxlen         = sizeof(sysctl_admin_reserve_kbytes),
1641                 .mode           = 0644,
1642                 .proc_handler   = proc_doulongvec_minmax,
1643         },
1644 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
1645         {
1646                 .procname       = "mmap_rnd_bits",
1647                 .data           = &mmap_rnd_bits,
1648                 .maxlen         = sizeof(mmap_rnd_bits),
1649                 .mode           = 0600,
1650                 .proc_handler   = proc_dointvec_minmax,
1651                 .extra1         = (void *)&mmap_rnd_bits_min,
1652                 .extra2         = (void *)&mmap_rnd_bits_max,
1653         },
1654 #endif
1655 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
1656         {
1657                 .procname       = "mmap_rnd_compat_bits",
1658                 .data           = &mmap_rnd_compat_bits,
1659                 .maxlen         = sizeof(mmap_rnd_compat_bits),
1660                 .mode           = 0600,
1661                 .proc_handler   = proc_dointvec_minmax,
1662                 .extra1         = (void *)&mmap_rnd_compat_bits_min,
1663                 .extra2         = (void *)&mmap_rnd_compat_bits_max,
1664         },
1665 #endif
1666         { }
1667 };
1668
1669 static struct ctl_table fs_table[] = {
1670         {
1671                 .procname       = "inode-nr",
1672                 .data           = &inodes_stat,
1673                 .maxlen         = 2*sizeof(long),
1674                 .mode           = 0444,
1675                 .proc_handler   = proc_nr_inodes,
1676         },
1677         {
1678                 .procname       = "inode-state",
1679                 .data           = &inodes_stat,
1680                 .maxlen         = 7*sizeof(long),
1681                 .mode           = 0444,
1682                 .proc_handler   = proc_nr_inodes,
1683         },
1684         {
1685                 .procname       = "file-nr",
1686                 .data           = &files_stat,
1687                 .maxlen         = sizeof(files_stat),
1688                 .mode           = 0444,
1689                 .proc_handler   = proc_nr_files,
1690         },
1691         {
1692                 .procname       = "file-max",
1693                 .data           = &files_stat.max_files,
1694                 .maxlen         = sizeof(files_stat.max_files),
1695                 .mode           = 0644,
1696                 .proc_handler   = proc_doulongvec_minmax,
1697         },
1698         {
1699                 .procname       = "nr_open",
1700                 .data           = &sysctl_nr_open,
1701                 .maxlen         = sizeof(unsigned int),
1702                 .mode           = 0644,
1703                 .proc_handler   = proc_dointvec_minmax,
1704                 .extra1         = &sysctl_nr_open_min,
1705                 .extra2         = &sysctl_nr_open_max,
1706         },
1707         {
1708                 .procname       = "dentry-state",
1709                 .data           = &dentry_stat,
1710                 .maxlen         = 6*sizeof(long),
1711                 .mode           = 0444,
1712                 .proc_handler   = proc_nr_dentry,
1713         },
1714         {
1715                 .procname       = "overflowuid",
1716                 .data           = &fs_overflowuid,
1717                 .maxlen         = sizeof(int),
1718                 .mode           = 0644,
1719                 .proc_handler   = proc_dointvec_minmax,
1720                 .extra1         = &minolduid,
1721                 .extra2         = &maxolduid,
1722         },
1723         {
1724                 .procname       = "overflowgid",
1725                 .data           = &fs_overflowgid,
1726                 .maxlen         = sizeof(int),
1727                 .mode           = 0644,
1728                 .proc_handler   = proc_dointvec_minmax,
1729                 .extra1         = &minolduid,
1730                 .extra2         = &maxolduid,
1731         },
1732 #ifdef CONFIG_FILE_LOCKING
1733         {
1734                 .procname       = "leases-enable",
1735                 .data           = &leases_enable,
1736                 .maxlen         = sizeof(int),
1737                 .mode           = 0644,
1738                 .proc_handler   = proc_dointvec,
1739         },
1740 #endif
1741 #ifdef CONFIG_DNOTIFY
1742         {
1743                 .procname       = "dir-notify-enable",
1744                 .data           = &dir_notify_enable,
1745                 .maxlen         = sizeof(int),
1746                 .mode           = 0644,
1747                 .proc_handler   = proc_dointvec,
1748         },
1749 #endif
1750 #ifdef CONFIG_MMU
1751 #ifdef CONFIG_FILE_LOCKING
1752         {
1753                 .procname       = "lease-break-time",
1754                 .data           = &lease_break_time,
1755                 .maxlen         = sizeof(int),
1756                 .mode           = 0644,
1757                 .proc_handler   = proc_dointvec,
1758         },
1759 #endif
1760 #ifdef CONFIG_AIO
1761         {
1762                 .procname       = "aio-nr",
1763                 .data           = &aio_nr,
1764                 .maxlen         = sizeof(aio_nr),
1765                 .mode           = 0444,
1766                 .proc_handler   = proc_doulongvec_minmax,
1767         },
1768         {
1769                 .procname       = "aio-max-nr",
1770                 .data           = &aio_max_nr,
1771                 .maxlen         = sizeof(aio_max_nr),
1772                 .mode           = 0644,
1773                 .proc_handler   = proc_doulongvec_minmax,
1774         },
1775 #endif /* CONFIG_AIO */
1776 #ifdef CONFIG_INOTIFY_USER
1777         {
1778                 .procname       = "inotify",
1779                 .mode           = 0555,
1780                 .child          = inotify_table,
1781         },
1782 #endif
1783 #ifdef CONFIG_EPOLL
1784         {
1785                 .procname       = "epoll",
1786                 .mode           = 0555,
1787                 .child          = epoll_table,
1788         },
1789 #endif
1790 #endif
1791         {
1792                 .procname       = "protected_symlinks",
1793                 .data           = &sysctl_protected_symlinks,
1794                 .maxlen         = sizeof(int),
1795                 .mode           = 0600,
1796                 .proc_handler   = proc_dointvec_minmax,
1797                 .extra1         = &zero,
1798                 .extra2         = &one,
1799         },
1800         {
1801                 .procname       = "protected_hardlinks",
1802                 .data           = &sysctl_protected_hardlinks,
1803                 .maxlen         = sizeof(int),
1804                 .mode           = 0600,
1805                 .proc_handler   = proc_dointvec_minmax,
1806                 .extra1         = &zero,
1807                 .extra2         = &one,
1808         },
1809         {
1810                 .procname       = "suid_dumpable",
1811                 .data           = &suid_dumpable,
1812                 .maxlen         = sizeof(int),
1813                 .mode           = 0644,
1814                 .proc_handler   = proc_dointvec_minmax_coredump,
1815                 .extra1         = &zero,
1816                 .extra2         = &two,
1817         },
1818 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1819         {
1820                 .procname       = "binfmt_misc",
1821                 .mode           = 0555,
1822                 .child          = sysctl_mount_point,
1823         },
1824 #endif
1825         {
1826                 .procname       = "pipe-max-size",
1827                 .data           = &pipe_max_size,
1828                 .maxlen         = sizeof(int),
1829                 .mode           = 0644,
1830                 .proc_handler   = &pipe_proc_fn,
1831                 .extra1         = &pipe_min_size,
1832         },
1833         {
1834                 .procname       = "pipe-user-pages-hard",
1835                 .data           = &pipe_user_pages_hard,
1836                 .maxlen         = sizeof(pipe_user_pages_hard),
1837                 .mode           = 0644,
1838                 .proc_handler   = proc_doulongvec_minmax,
1839         },
1840         {
1841                 .procname       = "pipe-user-pages-soft",
1842                 .data           = &pipe_user_pages_soft,
1843                 .maxlen         = sizeof(pipe_user_pages_soft),
1844                 .mode           = 0644,
1845                 .proc_handler   = proc_doulongvec_minmax,
1846         },
1847         {
1848                 .procname       = "mount-max",
1849                 .data           = &sysctl_mount_max,
1850                 .maxlen         = sizeof(unsigned int),
1851                 .mode           = 0644,
1852                 .proc_handler   = proc_dointvec_minmax,
1853                 .extra1         = &one,
1854         },
1855         { }
1856 };
1857
1858 static struct ctl_table debug_table[] = {
1859 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1860         {
1861                 .procname       = "exception-trace",
1862                 .data           = &show_unhandled_signals,
1863                 .maxlen         = sizeof(int),
1864                 .mode           = 0644,
1865                 .proc_handler   = proc_dointvec
1866         },
1867 #endif
1868 #if defined(CONFIG_OPTPROBES)
1869         {
1870                 .procname       = "kprobes-optimization",
1871                 .data           = &sysctl_kprobes_optimization,
1872                 .maxlen         = sizeof(int),
1873                 .mode           = 0644,
1874                 .proc_handler   = proc_kprobes_optimization_handler,
1875                 .extra1         = &zero,
1876                 .extra2         = &one,
1877         },
1878 #endif
1879         { }
1880 };
1881
1882 static struct ctl_table dev_table[] = {
1883         { }
1884 };
1885
1886 int __init sysctl_init(void)
1887 {
1888         struct ctl_table_header *hdr;
1889
1890         hdr = register_sysctl_table(sysctl_base_table);
1891         kmemleak_not_leak(hdr);
1892         return 0;
1893 }
1894
1895 #endif /* CONFIG_SYSCTL */
1896
1897 /*
1898  * /proc/sys support
1899  */
1900
1901 #ifdef CONFIG_PROC_SYSCTL
1902
1903 static int _proc_do_string(char *data, int maxlen, int write,
1904                            char __user *buffer,
1905                            size_t *lenp, loff_t *ppos)
1906 {
1907         size_t len;
1908         char __user *p;
1909         char c;
1910
1911         if (!data || !maxlen || !*lenp) {
1912                 *lenp = 0;
1913                 return 0;
1914         }
1915
1916         if (write) {
1917                 if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
1918                         /* Only continue writes not past the end of buffer. */
1919                         len = strlen(data);
1920                         if (len > maxlen - 1)
1921                                 len = maxlen - 1;
1922
1923                         if (*ppos > len)
1924                                 return 0;
1925                         len = *ppos;
1926                 } else {
1927                         /* Start writing from beginning of buffer. */
1928                         len = 0;
1929                 }
1930
1931                 *ppos += *lenp;
1932                 p = buffer;
1933                 while ((p - buffer) < *lenp && len < maxlen - 1) {
1934                         if (get_user(c, p++))
1935                                 return -EFAULT;
1936                         if (c == 0 || c == '\n')
1937                                 break;
1938                         data[len++] = c;
1939                 }
1940                 data[len] = 0;
1941         } else {
1942                 len = strlen(data);
1943                 if (len > maxlen)
1944                         len = maxlen;
1945
1946                 if (*ppos > len) {
1947                         *lenp = 0;
1948                         return 0;
1949                 }
1950
1951                 data += *ppos;
1952                 len  -= *ppos;
1953
1954                 if (len > *lenp)
1955                         len = *lenp;
1956                 if (len)
1957                         if (copy_to_user(buffer, data, len))
1958                                 return -EFAULT;
1959                 if (len < *lenp) {
1960                         if (put_user('\n', buffer + len))
1961                                 return -EFAULT;
1962                         len++;
1963                 }
1964                 *lenp = len;
1965                 *ppos += len;
1966         }
1967         return 0;
1968 }
1969
1970 static void warn_sysctl_write(struct ctl_table *table)
1971 {
1972         pr_warn_once("%s wrote to %s when file position was not 0!\n"
1973                 "This will not be supported in the future. To silence this\n"
1974                 "warning, set kernel.sysctl_writes_strict = -1\n",
1975                 current->comm, table->procname);
1976 }
1977
1978 /**
1979  * proc_first_pos_non_zero_ignore - check if firs position is allowed
1980  * @ppos: file position
1981  * @table: the sysctl table
1982  *
1983  * Returns true if the first position is non-zero and the sysctl_writes_strict
1984  * mode indicates this is not allowed for numeric input types. String proc
1985  * hadlers can ignore the return value.
1986  */
1987 static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
1988                                            struct ctl_table *table)
1989 {
1990         if (!*ppos)
1991                 return false;
1992
1993         switch (sysctl_writes_strict) {
1994         case SYSCTL_WRITES_STRICT:
1995                 return true;
1996         case SYSCTL_WRITES_WARN:
1997                 warn_sysctl_write(table);
1998                 return false;
1999         default:
2000                 return false;
2001         }
2002 }
2003
2004 /**
2005  * proc_dostring - read a string sysctl
2006  * @table: the sysctl table
2007  * @write: %TRUE if this is a write to the sysctl file
2008  * @buffer: the user buffer
2009  * @lenp: the size of the user buffer
2010  * @ppos: file position
2011  *
2012  * Reads/writes a string from/to the user buffer. If the kernel
2013  * buffer provided is not large enough to hold the string, the
2014  * string is truncated. The copied string is %NULL-terminated.
2015  * If the string is being read by the user process, it is copied
2016  * and a newline '\n' is added. It is truncated if the buffer is
2017  * not large enough.
2018  *
2019  * Returns 0 on success.
2020  */
2021 int proc_dostring(struct ctl_table *table, int write,
2022                   void __user *buffer, size_t *lenp, loff_t *ppos)
2023 {
2024         if (write)
2025                 proc_first_pos_non_zero_ignore(ppos, table);
2026
2027         return _proc_do_string((char *)(table->data), table->maxlen, write,
2028                                (char __user *)buffer, lenp, ppos);
2029 }
2030
2031 static size_t proc_skip_spaces(char **buf)
2032 {
2033         size_t ret;
2034         char *tmp = skip_spaces(*buf);
2035         ret = tmp - *buf;
2036         *buf = tmp;
2037         return ret;
2038 }
2039
2040 static void proc_skip_char(char **buf, size_t *size, const char v)
2041 {
2042         while (*size) {
2043                 if (**buf != v)
2044                         break;
2045                 (*size)--;
2046                 (*buf)++;
2047         }
2048 }
2049
2050 #define TMPBUFLEN 22
2051 /**
2052  * proc_get_long - reads an ASCII formatted integer from a user buffer
2053  *
2054  * @buf: a kernel buffer
2055  * @size: size of the kernel buffer
2056  * @val: this is where the number will be stored
2057  * @neg: set to %TRUE if number is negative
2058  * @perm_tr: a vector which contains the allowed trailers
2059  * @perm_tr_len: size of the perm_tr vector
2060  * @tr: pointer to store the trailer character
2061  *
2062  * In case of success %0 is returned and @buf and @size are updated with
2063  * the amount of bytes read. If @tr is non-NULL and a trailing
2064  * character exists (size is non-zero after returning from this
2065  * function), @tr is updated with the trailing character.
2066  */
2067 static int proc_get_long(char **buf, size_t *size,
2068                           unsigned long *val, bool *neg,
2069                           const char *perm_tr, unsigned perm_tr_len, char *tr)
2070 {
2071         int len;
2072         char *p, tmp[TMPBUFLEN];
2073
2074         if (!*size)
2075                 return -EINVAL;
2076
2077         len = *size;
2078         if (len > TMPBUFLEN - 1)
2079                 len = TMPBUFLEN - 1;
2080
2081         memcpy(tmp, *buf, len);
2082
2083         tmp[len] = 0;
2084         p = tmp;
2085         if (*p == '-' && *size > 1) {
2086                 *neg = true;
2087                 p++;
2088         } else
2089                 *neg = false;
2090         if (!isdigit(*p))
2091                 return -EINVAL;
2092
2093         *val = simple_strtoul(p, &p, 0);
2094
2095         len = p - tmp;
2096
2097         /* We don't know if the next char is whitespace thus we may accept
2098          * invalid integers (e.g. 1234...a) or two integers instead of one
2099          * (e.g. 123...1). So lets not allow such large numbers. */
2100         if (len == TMPBUFLEN - 1)
2101                 return -EINVAL;
2102
2103         if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2104                 return -EINVAL;
2105
2106         if (tr && (len < *size))
2107                 *tr = *p;
2108
2109         *buf += len;
2110         *size -= len;
2111
2112         return 0;
2113 }
2114
2115 /**
2116  * proc_put_long - converts an integer to a decimal ASCII formatted string
2117  *
2118  * @buf: the user buffer
2119  * @size: the size of the user buffer
2120  * @val: the integer to be converted
2121  * @neg: sign of the number, %TRUE for negative
2122  *
2123  * In case of success %0 is returned and @buf and @size are updated with
2124  * the amount of bytes written.
2125  */
2126 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2127                           bool neg)
2128 {
2129         int len;
2130         char tmp[TMPBUFLEN], *p = tmp;
2131
2132         sprintf(p, "%s%lu", neg ? "-" : "", val);
2133         len = strlen(tmp);
2134         if (len > *size)
2135                 len = *size;
2136         if (copy_to_user(*buf, tmp, len))
2137                 return -EFAULT;
2138         *size -= len;
2139         *buf += len;
2140         return 0;
2141 }
2142 #undef TMPBUFLEN
2143
2144 static int proc_put_char(void __user **buf, size_t *size, char c)
2145 {
2146         if (*size) {
2147                 char __user **buffer = (char __user **)buf;
2148                 if (put_user(c, *buffer))
2149                         return -EFAULT;
2150                 (*size)--, (*buffer)++;
2151                 *buf = *buffer;
2152         }
2153         return 0;
2154 }
2155
2156 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2157                                  int *valp,
2158                                  int write, void *data)
2159 {
2160         if (write) {
2161                 if (*negp) {
2162                         if (*lvalp > (unsigned long) INT_MAX + 1)
2163                                 return -EINVAL;
2164                         *valp = -*lvalp;
2165                 } else {
2166                         if (*lvalp > (unsigned long) INT_MAX)
2167                                 return -EINVAL;
2168                         *valp = *lvalp;
2169                 }
2170         } else {
2171                 int val = *valp;
2172                 if (val < 0) {
2173                         *negp = true;
2174                         *lvalp = -(unsigned long)val;
2175                 } else {
2176                         *negp = false;
2177                         *lvalp = (unsigned long)val;
2178                 }
2179         }
2180         return 0;
2181 }
2182
2183 static int do_proc_douintvec_conv(unsigned long *lvalp,
2184                                   unsigned int *valp,
2185                                   int write, void *data)
2186 {
2187         if (write) {
2188                 if (*lvalp > UINT_MAX)
2189                         return -EINVAL;
2190                 if (*lvalp > UINT_MAX)
2191                         return -EINVAL;
2192                 *valp = *lvalp;
2193         } else {
2194                 unsigned int val = *valp;
2195                 *lvalp = (unsigned long)val;
2196         }
2197         return 0;
2198 }
2199
2200 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2201
2202 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2203                   int write, void __user *buffer,
2204                   size_t *lenp, loff_t *ppos,
2205                   int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2206                               int write, void *data),
2207                   void *data)
2208 {
2209         int *i, vleft, first = 1, err = 0;
2210         size_t left;
2211         char *kbuf = NULL, *p;
2212
2213         if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2214                 *lenp = 0;
2215                 return 0;
2216         }
2217
2218         i = (int *) tbl_data;
2219         vleft = table->maxlen / sizeof(*i);
2220         left = *lenp;
2221
2222         if (!conv)
2223                 conv = do_proc_dointvec_conv;
2224
2225         if (write) {
2226                 if (proc_first_pos_non_zero_ignore(ppos, table))
2227                         goto out;
2228
2229                 if (left > PAGE_SIZE - 1)
2230                         left = PAGE_SIZE - 1;
2231                 p = kbuf = memdup_user_nul(buffer, left);
2232                 if (IS_ERR(kbuf))
2233                         return PTR_ERR(kbuf);
2234         }
2235
2236         for (; left && vleft--; i++, first=0) {
2237                 unsigned long lval;
2238                 bool neg;
2239
2240                 if (write) {
2241                         left -= proc_skip_spaces(&p);
2242
2243                         if (!left)
2244                                 break;
2245                         err = proc_get_long(&p, &left, &lval, &neg,
2246                                              proc_wspace_sep,
2247                                              sizeof(proc_wspace_sep), NULL);
2248                         if (err)
2249                                 break;
2250                         if (conv(&neg, &lval, i, 1, data)) {
2251                                 err = -EINVAL;
2252                                 break;
2253                         }
2254                 } else {
2255                         if (conv(&neg, &lval, i, 0, data)) {
2256                                 err = -EINVAL;
2257                                 break;
2258                         }
2259                         if (!first)
2260                                 err = proc_put_char(&buffer, &left, '\t');
2261                         if (err)
2262                                 break;
2263                         err = proc_put_long(&buffer, &left, lval, neg);
2264                         if (err)
2265                                 break;
2266                 }
2267         }
2268
2269         if (!write && !first && left && !err)
2270                 err = proc_put_char(&buffer, &left, '\n');
2271         if (write && !err && left)
2272                 left -= proc_skip_spaces(&p);
2273         if (write) {
2274                 kfree(kbuf);
2275                 if (first)
2276                         return err ? : -EINVAL;
2277         }
2278         *lenp -= left;
2279 out:
2280         *ppos += *lenp;
2281         return err;
2282 }
2283
2284 static int do_proc_dointvec(struct ctl_table *table, int write,
2285                   void __user *buffer, size_t *lenp, loff_t *ppos,
2286                   int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2287                               int write, void *data),
2288                   void *data)
2289 {
2290         return __do_proc_dointvec(table->data, table, write,
2291                         buffer, lenp, ppos, conv, data);
2292 }
2293
2294 static int do_proc_douintvec_w(unsigned int *tbl_data,
2295                                struct ctl_table *table,
2296                                void __user *buffer,
2297                                size_t *lenp, loff_t *ppos,
2298                                int (*conv)(unsigned long *lvalp,
2299                                            unsigned int *valp,
2300                                            int write, void *data),
2301                                void *data)
2302 {
2303         unsigned long lval;
2304         int err = 0;
2305         size_t left;
2306         bool neg;
2307         char *kbuf = NULL, *p;
2308
2309         left = *lenp;
2310
2311         if (proc_first_pos_non_zero_ignore(ppos, table))
2312                 goto bail_early;
2313
2314         if (left > PAGE_SIZE - 1)
2315                 left = PAGE_SIZE - 1;
2316
2317         p = kbuf = memdup_user_nul(buffer, left);
2318         if (IS_ERR(kbuf))
2319                 return -EINVAL;
2320
2321         left -= proc_skip_spaces(&p);
2322         if (!left) {
2323                 err = -EINVAL;
2324                 goto out_free;
2325         }
2326
2327         err = proc_get_long(&p, &left, &lval, &neg,
2328                              proc_wspace_sep,
2329                              sizeof(proc_wspace_sep), NULL);
2330         if (err || neg) {
2331                 err = -EINVAL;
2332                 goto out_free;
2333         }
2334
2335         if (conv(&lval, tbl_data, 1, data)) {
2336                 err = -EINVAL;
2337                 goto out_free;
2338         }
2339
2340         if (!err && left)
2341                 left -= proc_skip_spaces(&p);
2342
2343 out_free:
2344         kfree(kbuf);
2345         if (err)
2346                 return -EINVAL;
2347
2348         return 0;
2349
2350         /* This is in keeping with old __do_proc_dointvec() */
2351 bail_early:
2352         *ppos += *lenp;
2353         return err;
2354 }
2355
2356 static int do_proc_douintvec_r(unsigned int *tbl_data, void __user *buffer,
2357                                size_t *lenp, loff_t *ppos,
2358                                int (*conv)(unsigned long *lvalp,
2359                                            unsigned int *valp,
2360                                            int write, void *data),
2361                                void *data)
2362 {
2363         unsigned long lval;
2364         int err = 0;
2365         size_t left;
2366
2367         left = *lenp;
2368
2369         if (conv(&lval, tbl_data, 0, data)) {
2370                 err = -EINVAL;
2371                 goto out;
2372         }
2373
2374         err = proc_put_long(&buffer, &left, lval, false);
2375         if (err || !left)
2376                 goto out;
2377
2378         err = proc_put_char(&buffer, &left, '\n');
2379
2380 out:
2381         *lenp -= left;
2382         *ppos += *lenp;
2383
2384         return err;
2385 }
2386
2387 static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
2388                                int write, void __user *buffer,
2389                                size_t *lenp, loff_t *ppos,
2390                                int (*conv)(unsigned long *lvalp,
2391                                            unsigned int *valp,
2392                                            int write, void *data),
2393                                void *data)
2394 {
2395         unsigned int *i, vleft;
2396
2397         if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2398                 *lenp = 0;
2399                 return 0;
2400         }
2401
2402         i = (unsigned int *) tbl_data;
2403         vleft = table->maxlen / sizeof(*i);
2404
2405         /*
2406          * Arrays are not supported, keep this simple. *Do not* add
2407          * support for them.
2408          */
2409         if (vleft != 1) {
2410                 *lenp = 0;
2411                 return -EINVAL;
2412         }
2413
2414         if (!conv)
2415                 conv = do_proc_douintvec_conv;
2416
2417         if (write)
2418                 return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
2419                                            conv, data);
2420         return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
2421 }
2422
2423 static int do_proc_douintvec(struct ctl_table *table, int write,
2424                              void __user *buffer, size_t *lenp, loff_t *ppos,
2425                              int (*conv)(unsigned long *lvalp,
2426                                          unsigned int *valp,
2427                                          int write, void *data),
2428                              void *data)
2429 {
2430         return __do_proc_douintvec(table->data, table, write,
2431                                    buffer, lenp, ppos, conv, data);
2432 }
2433
2434 /**
2435  * proc_dointvec - read a vector of integers
2436  * @table: the sysctl table
2437  * @write: %TRUE if this is a write to the sysctl file
2438  * @buffer: the user buffer
2439  * @lenp: the size of the user buffer
2440  * @ppos: file position
2441  *
2442  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2443  * values from/to the user buffer, treated as an ASCII string.
2444  *
2445  * Returns 0 on success.
2446  */
2447 int proc_dointvec(struct ctl_table *table, int write,
2448                      void __user *buffer, size_t *lenp, loff_t *ppos)
2449 {
2450         return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
2451 }
2452
2453 /**
2454  * proc_douintvec - read a vector of unsigned integers
2455  * @table: the sysctl table
2456  * @write: %TRUE if this is a write to the sysctl file
2457  * @buffer: the user buffer
2458  * @lenp: the size of the user buffer
2459  * @ppos: file position
2460  *
2461  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2462  * values from/to the user buffer, treated as an ASCII string.
2463  *
2464  * Returns 0 on success.
2465  */
2466 int proc_douintvec(struct ctl_table *table, int write,
2467                      void __user *buffer, size_t *lenp, loff_t *ppos)
2468 {
2469         return do_proc_douintvec(table, write, buffer, lenp, ppos,
2470                                  do_proc_douintvec_conv, NULL);
2471 }
2472
2473 /*
2474  * Taint values can only be increased
2475  * This means we can safely use a temporary.
2476  */
2477 static int proc_taint(struct ctl_table *table, int write,
2478                                void __user *buffer, size_t *lenp, loff_t *ppos)
2479 {
2480         struct ctl_table t;
2481         unsigned long tmptaint = get_taint();
2482         int err;
2483
2484         if (write && !capable(CAP_SYS_ADMIN))
2485                 return -EPERM;
2486
2487         t = *table;
2488         t.data = &tmptaint;
2489         err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2490         if (err < 0)
2491                 return err;
2492
2493         if (write) {
2494                 /*
2495                  * Poor man's atomic or. Not worth adding a primitive
2496                  * to everyone's atomic.h for this
2497                  */
2498                 int i;
2499                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2500                         if ((tmptaint >> i) & 1)
2501                                 add_taint(i, LOCKDEP_STILL_OK);
2502                 }
2503         }
2504
2505         return err;
2506 }
2507
2508 #ifdef CONFIG_PRINTK
2509 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2510                                 void __user *buffer, size_t *lenp, loff_t *ppos)
2511 {
2512         if (write && !capable(CAP_SYS_ADMIN))
2513                 return -EPERM;
2514
2515         return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2516 }
2517 #endif
2518
2519 struct do_proc_dointvec_minmax_conv_param {
2520         int *min;
2521         int *max;
2522 };
2523
2524 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2525                                         int *valp,
2526                                         int write, void *data)
2527 {
2528         struct do_proc_dointvec_minmax_conv_param *param = data;
2529         if (write) {
2530                 int val = *negp ? -*lvalp : *lvalp;
2531                 if ((param->min && *param->min > val) ||
2532                     (param->max && *param->max < val))
2533                         return -EINVAL;
2534                 *valp = val;
2535         } else {
2536                 int val = *valp;
2537                 if (val < 0) {
2538                         *negp = true;
2539                         *lvalp = -(unsigned long)val;
2540                 } else {
2541                         *negp = false;
2542                         *lvalp = (unsigned long)val;
2543                 }
2544         }
2545         return 0;
2546 }
2547
2548 /**
2549  * proc_dointvec_minmax - read a vector of integers with min/max values
2550  * @table: the sysctl table
2551  * @write: %TRUE if this is a write to the sysctl file
2552  * @buffer: the user buffer
2553  * @lenp: the size of the user buffer
2554  * @ppos: file position
2555  *
2556  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2557  * values from/to the user buffer, treated as an ASCII string.
2558  *
2559  * This routine will ensure the values are within the range specified by
2560  * table->extra1 (min) and table->extra2 (max).
2561  *
2562  * Returns 0 on success.
2563  */
2564 int proc_dointvec_minmax(struct ctl_table *table, int write,
2565                   void __user *buffer, size_t *lenp, loff_t *ppos)
2566 {
2567         struct do_proc_dointvec_minmax_conv_param param = {
2568                 .min = (int *) table->extra1,
2569                 .max = (int *) table->extra2,
2570         };
2571         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2572                                 do_proc_dointvec_minmax_conv, &param);
2573 }
2574
2575 struct do_proc_douintvec_minmax_conv_param {
2576         unsigned int *min;
2577         unsigned int *max;
2578 };
2579
2580 static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
2581                                          unsigned int *valp,
2582                                          int write, void *data)
2583 {
2584         struct do_proc_douintvec_minmax_conv_param *param = data;
2585
2586         if (write) {
2587                 unsigned int val = *lvalp;
2588
2589                 if ((param->min && *param->min > val) ||
2590                     (param->max && *param->max < val))
2591                         return -ERANGE;
2592
2593                 if (*lvalp > UINT_MAX)
2594                         return -EINVAL;
2595                 *valp = val;
2596         } else {
2597                 unsigned int val = *valp;
2598                 *lvalp = (unsigned long) val;
2599         }
2600
2601         return 0;
2602 }
2603
2604 /**
2605  * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
2606  * @table: the sysctl table
2607  * @write: %TRUE if this is a write to the sysctl file
2608  * @buffer: the user buffer
2609  * @lenp: the size of the user buffer
2610  * @ppos: file position
2611  *
2612  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2613  * values from/to the user buffer, treated as an ASCII string. Negative
2614  * strings are not allowed.
2615  *
2616  * This routine will ensure the values are within the range specified by
2617  * table->extra1 (min) and table->extra2 (max). There is a final sanity
2618  * check for UINT_MAX to avoid having to support wrap around uses from
2619  * userspace.
2620  *
2621  * Returns 0 on success.
2622  */
2623 int proc_douintvec_minmax(struct ctl_table *table, int write,
2624                           void __user *buffer, size_t *lenp, loff_t *ppos)
2625 {
2626         struct do_proc_douintvec_minmax_conv_param param = {
2627                 .min = (unsigned int *) table->extra1,
2628                 .max = (unsigned int *) table->extra2,
2629         };
2630         return do_proc_douintvec(table, write, buffer, lenp, ppos,
2631                                  do_proc_douintvec_minmax_conv, &param);
2632 }
2633
2634 static void validate_coredump_safety(void)
2635 {
2636 #ifdef CONFIG_COREDUMP
2637         if (suid_dumpable == SUID_DUMP_ROOT &&
2638             core_pattern[0] != '/' && core_pattern[0] != '|') {
2639                 printk(KERN_WARNING
2640 "Unsafe core_pattern used with fs.suid_dumpable=2.\n"
2641 "Pipe handler or fully qualified core dump path required.\n"
2642 "Set kernel.core_pattern before fs.suid_dumpable.\n"
2643                 );
2644         }
2645 #endif
2646 }
2647
2648 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2649                 void __user *buffer, size_t *lenp, loff_t *ppos)
2650 {
2651         int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2652         if (!error)
2653                 validate_coredump_safety();
2654         return error;
2655 }
2656
2657 #ifdef CONFIG_COREDUMP
2658 static int proc_dostring_coredump(struct ctl_table *table, int write,
2659                   void __user *buffer, size_t *lenp, loff_t *ppos)
2660 {
2661         int error = proc_dostring(table, write, buffer, lenp, ppos);
2662         if (!error)
2663                 validate_coredump_safety();
2664         return error;
2665 }
2666 #endif
2667
2668 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2669                                      void __user *buffer,
2670                                      size_t *lenp, loff_t *ppos,
2671                                      unsigned long convmul,
2672                                      unsigned long convdiv)
2673 {
2674         unsigned long *i, *min, *max;
2675         int vleft, first = 1, err = 0;
2676         size_t left;
2677         char *kbuf = NULL, *p;
2678
2679         if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2680                 *lenp = 0;
2681                 return 0;
2682         }
2683
2684         i = (unsigned long *) data;
2685         min = (unsigned long *) table->extra1;
2686         max = (unsigned long *) table->extra2;
2687         vleft = table->maxlen / sizeof(unsigned long);
2688         left = *lenp;
2689
2690         if (write) {
2691                 if (proc_first_pos_non_zero_ignore(ppos, table))
2692                         goto out;
2693
2694                 if (left > PAGE_SIZE - 1)
2695                         left = PAGE_SIZE - 1;
2696                 p = kbuf = memdup_user_nul(buffer, left);
2697                 if (IS_ERR(kbuf))
2698                         return PTR_ERR(kbuf);
2699         }
2700
2701         for (; left && vleft--; i++, first = 0) {
2702                 unsigned long val;
2703
2704                 if (write) {
2705                         bool neg;
2706
2707                         left -= proc_skip_spaces(&p);
2708
2709                         err = proc_get_long(&p, &left, &val, &neg,
2710                                              proc_wspace_sep,
2711                                              sizeof(proc_wspace_sep), NULL);
2712                         if (err)
2713                                 break;
2714                         if (neg)
2715                                 continue;
2716                         val = convmul * val / convdiv;
2717                         if ((min && val < *min) || (max && val > *max))
2718                                 continue;
2719                         *i = val;
2720                 } else {
2721                         val = convdiv * (*i) / convmul;
2722                         if (!first) {
2723                                 err = proc_put_char(&buffer, &left, '\t');
2724                                 if (err)
2725                                         break;
2726                         }
2727                         err = proc_put_long(&buffer, &left, val, false);
2728                         if (err)
2729                                 break;
2730                 }
2731         }
2732
2733         if (!write && !first && left && !err)
2734                 err = proc_put_char(&buffer, &left, '\n');
2735         if (write && !err)
2736                 left -= proc_skip_spaces(&p);
2737         if (write) {
2738                 kfree(kbuf);
2739                 if (first)
2740                         return err ? : -EINVAL;
2741         }
2742         *lenp -= left;
2743 out:
2744         *ppos += *lenp;
2745         return err;
2746 }
2747
2748 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2749                                      void __user *buffer,
2750                                      size_t *lenp, loff_t *ppos,
2751                                      unsigned long convmul,
2752                                      unsigned long convdiv)
2753 {
2754         return __do_proc_doulongvec_minmax(table->data, table, write,
2755                         buffer, lenp, ppos, convmul, convdiv);
2756 }
2757
2758 /**
2759  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2760  * @table: the sysctl table
2761  * @write: %TRUE if this is a write to the sysctl file
2762  * @buffer: the user buffer
2763  * @lenp: the size of the user buffer
2764  * @ppos: file position
2765  *
2766  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2767  * values from/to the user buffer, treated as an ASCII string.
2768  *
2769  * This routine will ensure the values are within the range specified by
2770  * table->extra1 (min) and table->extra2 (max).
2771  *
2772  * Returns 0 on success.
2773  */
2774 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2775                            void __user *buffer, size_t *lenp, loff_t *ppos)
2776 {
2777     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2778 }
2779
2780 /**
2781  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2782  * @table: the sysctl table
2783  * @write: %TRUE if this is a write to the sysctl file
2784  * @buffer: the user buffer
2785  * @lenp: the size of the user buffer
2786  * @ppos: file position
2787  *
2788  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2789  * values from/to the user buffer, treated as an ASCII string. The values
2790  * are treated as milliseconds, and converted to jiffies when they are stored.
2791  *
2792  * This routine will ensure the values are within the range specified by
2793  * table->extra1 (min) and table->extra2 (max).
2794  *
2795  * Returns 0 on success.
2796  */
2797 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2798                                       void __user *buffer,
2799                                       size_t *lenp, loff_t *ppos)
2800 {
2801     return do_proc_doulongvec_minmax(table, write, buffer,
2802                                      lenp, ppos, HZ, 1000l);
2803 }
2804
2805
2806 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2807                                          int *valp,
2808                                          int write, void *data)
2809 {
2810         if (write) {
2811                 if (*lvalp > INT_MAX / HZ)
2812                         return 1;
2813                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2814         } else {
2815                 int val = *valp;
2816                 unsigned long lval;
2817                 if (val < 0) {
2818                         *negp = true;
2819                         lval = -(unsigned long)val;
2820                 } else {
2821                         *negp = false;
2822                         lval = (unsigned long)val;
2823                 }
2824                 *lvalp = lval / HZ;
2825         }
2826         return 0;
2827 }
2828
2829 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2830                                                 int *valp,
2831                                                 int write, void *data)
2832 {
2833         if (write) {
2834                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2835                         return 1;
2836                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2837         } else {
2838                 int val = *valp;
2839                 unsigned long lval;
2840                 if (val < 0) {
2841                         *negp = true;
2842                         lval = -(unsigned long)val;
2843                 } else {
2844                         *negp = false;
2845                         lval = (unsigned long)val;
2846                 }
2847                 *lvalp = jiffies_to_clock_t(lval);
2848         }
2849         return 0;
2850 }
2851
2852 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2853                                             int *valp,
2854                                             int write, void *data)
2855 {
2856         if (write) {
2857                 unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2858
2859                 if (jif > INT_MAX)
2860                         return 1;
2861                 *valp = (int)jif;
2862         } else {
2863                 int val = *valp;
2864                 unsigned long lval;
2865                 if (val < 0) {
2866                         *negp = true;
2867                         lval = -(unsigned long)val;
2868                 } else {
2869                         *negp = false;
2870                         lval = (unsigned long)val;
2871                 }
2872                 *lvalp = jiffies_to_msecs(lval);
2873         }
2874         return 0;
2875 }
2876
2877 /**
2878  * proc_dointvec_jiffies - read a vector of integers as seconds
2879  * @table: the sysctl table
2880  * @write: %TRUE if this is a write to the sysctl file
2881  * @buffer: the user buffer
2882  * @lenp: the size of the user buffer
2883  * @ppos: file position
2884  *
2885  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2886  * values from/to the user buffer, treated as an ASCII string.
2887  * The values read are assumed to be in seconds, and are converted into
2888  * jiffies.
2889  *
2890  * Returns 0 on success.
2891  */
2892 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2893                           void __user *buffer, size_t *lenp, loff_t *ppos)
2894 {
2895     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2896                             do_proc_dointvec_jiffies_conv,NULL);
2897 }
2898
2899 /**
2900  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2901  * @table: the sysctl table
2902  * @write: %TRUE if this is a write to the sysctl file
2903  * @buffer: the user buffer
2904  * @lenp: the size of the user buffer
2905  * @ppos: pointer to the file position
2906  *
2907  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2908  * values from/to the user buffer, treated as an ASCII string.
2909  * The values read are assumed to be in 1/USER_HZ seconds, and
2910  * are converted into jiffies.
2911  *
2912  * Returns 0 on success.
2913  */
2914 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2915                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2916 {
2917     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2918                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2919 }
2920
2921 /**
2922  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2923  * @table: the sysctl table
2924  * @write: %TRUE if this is a write to the sysctl file
2925  * @buffer: the user buffer
2926  * @lenp: the size of the user buffer
2927  * @ppos: file position
2928  * @ppos: the current position in the file
2929  *
2930  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2931  * values from/to the user buffer, treated as an ASCII string.
2932  * The values read are assumed to be in 1/1000 seconds, and
2933  * are converted into jiffies.
2934  *
2935  * Returns 0 on success.
2936  */
2937 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2938                              void __user *buffer, size_t *lenp, loff_t *ppos)
2939 {
2940         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2941                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2942 }
2943
2944 static int proc_do_cad_pid(struct ctl_table *table, int write,
2945                            void __user *buffer, size_t *lenp, loff_t *ppos)
2946 {
2947         struct pid *new_pid;
2948         pid_t tmp;
2949         int r;
2950
2951         tmp = pid_vnr(cad_pid);
2952
2953         r = __do_proc_dointvec(&tmp, table, write, buffer,
2954                                lenp, ppos, NULL, NULL);
2955         if (r || !write)
2956                 return r;
2957
2958         new_pid = find_get_pid(tmp);
2959         if (!new_pid)
2960                 return -ESRCH;
2961
2962         put_pid(xchg(&cad_pid, new_pid));
2963         return 0;
2964 }
2965
2966 /**
2967  * proc_do_large_bitmap - read/write from/to a large bitmap
2968  * @table: the sysctl table
2969  * @write: %TRUE if this is a write to the sysctl file
2970  * @buffer: the user buffer
2971  * @lenp: the size of the user buffer
2972  * @ppos: file position
2973  *
2974  * The bitmap is stored at table->data and the bitmap length (in bits)
2975  * in table->maxlen.
2976  *
2977  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2978  * large bitmaps may be represented in a compact manner. Writing into
2979  * the file will clear the bitmap then update it with the given input.
2980  *
2981  * Returns 0 on success.
2982  */
2983 int proc_do_large_bitmap(struct ctl_table *table, int write,
2984                          void __user *buffer, size_t *lenp, loff_t *ppos)
2985 {
2986         int err = 0;
2987         bool first = 1;
2988         size_t left = *lenp;
2989         unsigned long bitmap_len = table->maxlen;
2990         unsigned long *bitmap = *(unsigned long **) table->data;
2991         unsigned long *tmp_bitmap = NULL;
2992         char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2993
2994         if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
2995                 *lenp = 0;
2996                 return 0;
2997         }
2998
2999         if (write) {
3000                 char *kbuf, *p;
3001
3002                 if (left > PAGE_SIZE - 1)
3003                         left = PAGE_SIZE - 1;
3004
3005                 p = kbuf = memdup_user_nul(buffer, left);
3006                 if (IS_ERR(kbuf))
3007                         return PTR_ERR(kbuf);
3008
3009                 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
3010                                      GFP_KERNEL);
3011                 if (!tmp_bitmap) {
3012                         kfree(kbuf);
3013                         return -ENOMEM;
3014                 }
3015                 proc_skip_char(&p, &left, '\n');
3016                 while (!err && left) {
3017                         unsigned long val_a, val_b;
3018                         bool neg;
3019
3020                         err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
3021                                              sizeof(tr_a), &c);
3022                         if (err)
3023                                 break;
3024                         if (val_a >= bitmap_len || neg) {
3025                                 err = -EINVAL;
3026                                 break;
3027                         }
3028
3029                         val_b = val_a;
3030                         if (left) {
3031                                 p++;
3032                                 left--;
3033                         }
3034
3035                         if (c == '-') {
3036                                 err = proc_get_long(&p, &left, &val_b,
3037                                                      &neg, tr_b, sizeof(tr_b),
3038                                                      &c);
3039                                 if (err)
3040                                         break;
3041                                 if (val_b >= bitmap_len || neg ||
3042                                     val_a > val_b) {
3043                                         err = -EINVAL;
3044                                         break;
3045                                 }
3046                                 if (left) {
3047                                         p++;
3048                                         left--;
3049                                 }
3050                         }
3051
3052                         bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
3053                         first = 0;
3054                         proc_skip_char(&p, &left, '\n');
3055                 }
3056                 kfree(kbuf);
3057         } else {
3058                 unsigned long bit_a, bit_b = 0;
3059
3060                 while (left) {
3061                         bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
3062                         if (bit_a >= bitmap_len)
3063                                 break;
3064                         bit_b = find_next_zero_bit(bitmap, bitmap_len,
3065                                                    bit_a + 1) - 1;
3066
3067                         if (!first) {
3068                                 err = proc_put_char(&buffer, &left, ',');
3069                                 if (err)
3070                                         break;
3071                         }
3072                         err = proc_put_long(&buffer, &left, bit_a, false);
3073                         if (err)
3074                                 break;
3075                         if (bit_a != bit_b) {
3076                                 err = proc_put_char(&buffer, &left, '-');
3077                                 if (err)
3078                                         break;
3079                                 err = proc_put_long(&buffer, &left, bit_b, false);
3080                                 if (err)
3081                                         break;
3082                         }
3083
3084                         first = 0; bit_b++;
3085                 }
3086                 if (!err)
3087                         err = proc_put_char(&buffer, &left, '\n');
3088         }
3089
3090         if (!err) {
3091                 if (write) {
3092                         if (*ppos)
3093                                 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
3094                         else
3095                                 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
3096                 }
3097                 kfree(tmp_bitmap);
3098                 *lenp -= left;
3099                 *ppos += *lenp;
3100                 return 0;
3101         } else {
3102                 kfree(tmp_bitmap);
3103                 return err;
3104         }
3105 }
3106
3107 #else /* CONFIG_PROC_SYSCTL */
3108
3109 int proc_dostring(struct ctl_table *table, int write,
3110                   void __user *buffer, size_t *lenp, loff_t *ppos)
3111 {
3112         return -ENOSYS;
3113 }
3114
3115 int proc_dointvec(struct ctl_table *table, int write,
3116                   void __user *buffer, size_t *lenp, loff_t *ppos)
3117 {
3118         return -ENOSYS;
3119 }
3120
3121 int proc_douintvec(struct ctl_table *table, int write,
3122                   void __user *buffer, size_t *lenp, loff_t *ppos)
3123 {
3124         return -ENOSYS;
3125 }
3126
3127 int proc_dointvec_minmax(struct ctl_table *table, int write,
3128                     void __user *buffer, size_t *lenp, loff_t *ppos)
3129 {
3130         return -ENOSYS;
3131 }
3132
3133 int proc_douintvec_minmax(struct ctl_table *table, int write,
3134                           void __user *buffer, size_t *lenp, loff_t *ppos)
3135 {
3136         return -ENOSYS;
3137 }
3138
3139 int proc_dointvec_jiffies(struct ctl_table *table, int write,
3140                     void __user *buffer, size_t *lenp, loff_t *ppos)
3141 {
3142         return -ENOSYS;
3143 }
3144
3145 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
3146                     void __user *buffer, size_t *lenp, loff_t *ppos)
3147 {
3148         return -ENOSYS;
3149 }
3150
3151 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
3152                              void __user *buffer, size_t *lenp, loff_t *ppos)
3153 {
3154         return -ENOSYS;
3155 }
3156
3157 int proc_doulongvec_minmax(struct ctl_table *table, int write,
3158                     void __user *buffer, size_t *lenp, loff_t *ppos)
3159 {
3160         return -ENOSYS;
3161 }
3162
3163 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
3164                                       void __user *buffer,
3165                                       size_t *lenp, loff_t *ppos)
3166 {
3167     return -ENOSYS;
3168 }
3169
3170
3171 #endif /* CONFIG_PROC_SYSCTL */
3172
3173 /*
3174  * No sense putting this after each symbol definition, twice,
3175  * exception granted :-)
3176  */
3177 EXPORT_SYMBOL(proc_dointvec);
3178 EXPORT_SYMBOL(proc_douintvec);
3179 EXPORT_SYMBOL(proc_dointvec_jiffies);
3180 EXPORT_SYMBOL(proc_dointvec_minmax);
3181 EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
3182 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3183 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3184 EXPORT_SYMBOL(proc_dostring);
3185 EXPORT_SYMBOL(proc_doulongvec_minmax);
3186 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);