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