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