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/kmemleak.h>
  34 #include <linux/fs.h>
  35 #include <linux/init.h>
  36 #include <linux/kernel.h>
  37 #include <linux/kobject.h>
  38 #include <linux/net.h>
  39 #include <linux/sysrq.h>
  40 #include <linux/highuid.h>
  41 #include <linux/writeback.h>
  42 #include <linux/ratelimit.h>
  43 #include <linux/compaction.h>
  44 #include <linux/hugetlb.h>
  45 #include <linux/initrd.h>
  46 #include <linux/key.h>
  47 #include <linux/times.h>
  48 #include <linux/limits.h>
  49 #include <linux/dcache.h>
  50 #include <linux/dnotify.h>
  51 #include <linux/syscalls.h>
  52 #include <linux/vmstat.h>
  53 #include <linux/nfs_fs.h>
  54 #include <linux/acpi.h>
  55 #include <linux/reboot.h>
  56 #include <linux/ftrace.h>
  57 #include <linux/perf_event.h>
  58 #include <linux/kprobes.h>
  59 #include <linux/pipe_fs_i.h>
  60 #include <linux/oom.h>
  61 #include <linux/kmod.h>
  62 #include <linux/capability.h>
  63 #include <linux/binfmts.h>
  64 #include <linux/sched/sysctl.h>
  65 #include <linux/sched/coredump.h>
  66 #include <linux/kexec.h>
  67 #include <linux/bpf.h>
  68 #include <linux/mount.h>
  69 #include <linux/pipe_fs_i.h>
  70
  71 #include <linux/uaccess.h>
  72 #include <asm/processor.h>
  73
  74 #ifdef CONFIG_X86
  75 #include <asm/nmi.h>
  76 #include <asm/stacktrace.h>
  77 #include <asm/io.h>
  78 #endif
  79 #ifdef CONFIG_SPARC
  80 #include <asm/setup.h>
  81 #endif
  82 #ifdef CONFIG_BSD_PROCESS_ACCT
  83 #include <linux/acct.h>
  84 #endif
  85 #ifdef CONFIG_RT_MUTEXES
  86 #include <linux/rtmutex.h>
  87 #endif
  88 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
  89 #include <linux/lockdep.h>
  90 #endif
  91 #ifdef CONFIG_CHR_DEV_SG
  92 #include <scsi/sg.h>
  93 #endif
  94
  95 #ifdef CONFIG_LOCKUP_DETECTOR
  96 #include <linux/nmi.h>
  97 #endif
  98
  99 #if defined(CONFIG_SYSCTL)
 100
 101 /* External variables not in a header file. */
 102 extern int suid_dumpable;
 103 #ifdef CONFIG_COREDUMP
 104 extern int core_uses_pid;
 105 extern char core_pattern[];
 106 extern unsigned int core_pipe_limit;
 107 #endif
 108 extern int pid_max;
 109 extern int pid_max_min, pid_max_max;
 110 extern int percpu_pagelist_fraction;
 111 extern int latencytop_enabled;
 112 extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
 113 #ifndef CONFIG_MMU
 114 extern int sysctl_nr_trim_pages;
 115 #endif
 116
 117 /* Constants used for minimum and  maximum */
 118 #ifdef CONFIG_LOCKUP_DETECTOR
 119 static int sixty = 60;
 120 #endif
 121
 122 static int __maybe_unused neg_one = -1;
 123
 124 static int zero;
 125 static int __maybe_unused one = 1;
 126 static int __maybe_unused two = 2;
 127 static int __maybe_unused four = 4;
 128 static unsigned long one_ul = 1;
 129 static int one_hundred = 100;
 130 static int one_thousand = 1000;
 131 #ifdef CONFIG_PRINTK
 132 static int ten_thousand = 10000;
 133 #endif
 134 #ifdef CONFIG_PERF_EVENTS
 135 static int six_hundred_forty_kb = 640 * 1024;
 136 #endif
 137
 138 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
 139 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
 140
 141 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
 142 static int maxolduid = 65535;
 143 static int minolduid;
 144
 145 static int ngroups_max = NGROUPS_MAX;
 146 static const int cap_last_cap = CAP_LAST_CAP;
 147
 148 /*this is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs */
 149 #ifdef CONFIG_DETECT_HUNG_TASK
 150 static unsigned long hung_task_timeout_max = (LONG_MAX/HZ);
 151 #endif
 152
 153 #ifdef CONFIG_INOTIFY_USER
 154 #include <linux/inotify.h>
 155 #endif
 156 #ifdef CONFIG_SPARC
 157 #endif
 158
 159 #ifdef __hppa__
 160 extern int pwrsw_enabled;
 161 #endif
 162
 163 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
 164 extern int unaligned_enabled;
 165 #endif
 166
 167 #ifdef CONFIG_IA64
 168 extern int unaligned_dump_stack;
 169 #endif
 170
 171 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
 172 extern int no_unaligned_warning;
 173 #endif
 174
 175 #ifdef CONFIG_PROC_SYSCTL
 176
 177 /**
 178  * enum sysctl_writes_mode - supported sysctl write modes
 179  *
 180  * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
 181  *      to be written, and multiple writes on the same sysctl file descriptor
 182  *      will rewrite the sysctl value, regardless of file position. No warning
 183  *      is issued when the initial position is not 0.
 184  * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
 185  *      not 0.
 186  * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
 187  *      file position 0 and the value must be fully contained in the buffer
 188  *      sent to the write syscall. If dealing with strings respect the file
 189  *      position, but restrict this to the max length of the buffer, anything
 190  *      passed the max lenght will be ignored. Multiple writes will append
 191  *      to the buffer.
 192  *
 193  * These write modes control how current file position affects the behavior of
 194  * updating sysctl values through the proc interface on each write.
 195  */
 196 enum sysctl_writes_mode {
 197         SYSCTL_WRITES_LEGACY            = -1,
 198         SYSCTL_WRITES_WARN              = 0,
 199         SYSCTL_WRITES_STRICT            = 1,
 200 };
 201
 202 static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
 203
 204 static int proc_do_cad_pid(struct ctl_table *table, int write,
 205                   void __user *buffer, size_t *lenp, loff_t *ppos);
 206 static int proc_taint(struct ctl_table *table, int write,
 207                                void __user *buffer, size_t *lenp, loff_t *ppos);
 208 #endif
 209
 210 #ifdef CONFIG_PRINTK
 211 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
 212                                 void __user *buffer, size_t *lenp, loff_t *ppos);
 213 #endif
 214
 215 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
 216                 void __user *buffer, size_t *lenp, loff_t *ppos);
 217 #ifdef CONFIG_COREDUMP
 218 static int proc_dostring_coredump(struct ctl_table *table, int write,
 219                 void __user *buffer, size_t *lenp, loff_t *ppos);
 220 #endif
 221
 222 #ifdef CONFIG_MAGIC_SYSRQ
 223 /* Note: sysrq code uses it's own private copy */
 224 static int __sysrq_enabled = CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE;
 225
 226 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
 227                                 void __user *buffer, size_t *lenp,
 228                                 loff_t *ppos)
 229 {
 230         int error;
 231
 232         error = proc_dointvec(table, write, buffer, lenp, ppos);
 233         if (error)
 234                 return error;
 235
 236         if (write)
 237                 sysrq_toggle_support(__sysrq_enabled);
 238
 239         return 0;
 240 }
 241
 242 #endif
 243
 244 static struct ctl_table kern_table[];
 245 static struct ctl_table vm_table[];
 246 static struct ctl_table fs_table[];
 247 static struct ctl_table debug_table[];
 248 static struct ctl_table dev_table[];
 249 extern struct ctl_table random_table[];
 250 #ifdef CONFIG_EPOLL
 251 extern struct ctl_table epoll_table[];
 252 #endif
 253
 254 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 255 int sysctl_legacy_va_layout;
 256 #endif
 257
 258 /* The default sysctl tables: */
 259
 260 static struct ctl_table sysctl_base_table[] = {
 261         {
 262                 .procname       = "kernel",
 263                 .mode           = 0555,
 264                 .child          = kern_table,
 265         },
 266         {
 267                 .procname       = "vm",
 268                 .mode           = 0555,
 269                 .child          = vm_table,
 270         },
 271         {
 272                 .procname       = "fs",
 273                 .mode           = 0555,
 274                 .child          = fs_table,
 275         },
 276         {
 277                 .procname       = "debug",
 278                 .mode           = 0555,
 279                 .child          = debug_table,
 280         },
 281         {
 282                 .procname       = "dev",
 283                 .mode           = 0555,
 284                 .child          = dev_table,
 285         },
 286         { }
 287 };
 288
 289 #ifdef CONFIG_SCHED_DEBUG
 290 static int min_sched_granularity_ns = 100000;           /* 100 usecs */
 291 static int max_sched_granularity_ns = NSEC_PER_SEC;     /* 1 second */
 292 static int min_wakeup_granularity_ns;                   /* 0 usecs */
 293 static int max_wakeup_granularity_ns = NSEC_PER_SEC;    /* 1 second */
 294 #ifdef CONFIG_SMP
 295 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
 296 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
 297 #endif /* CONFIG_SMP */
 298 #endif /* CONFIG_SCHED_DEBUG */
 299
 300 #ifdef CONFIG_COMPACTION
 301 static int min_extfrag_threshold;
 302 static int max_extfrag_threshold = 1000;
 303 #endif
 304
 305 static struct ctl_table kern_table[] = {
 306         {
 307                 .procname       = "sched_child_runs_first",
 308                 .data           = &sysctl_sched_child_runs_first,
 309                 .maxlen         = sizeof(unsigned int),
 310                 .mode           = 0644,
 311                 .proc_handler   = proc_dointvec,
 312         },
 313 #ifdef CONFIG_SCHED_DEBUG
 314         {
 315                 .procname       = "sched_min_granularity_ns",
 316                 .data           = &sysctl_sched_min_granularity,
 317                 .maxlen         = sizeof(unsigned int),
 318                 .mode           = 0644,
 319                 .proc_handler   = sched_proc_update_handler,
 320                 .extra1         = &min_sched_granularity_ns,
 321                 .extra2         = &max_sched_granularity_ns,
 322         },
 323         {
 324                 .procname       = "sched_latency_ns",
 325                 .data           = &sysctl_sched_latency,
 326                 .maxlen         = sizeof(unsigned int),
 327                 .mode           = 0644,
 328                 .proc_handler   = sched_proc_update_handler,
 329                 .extra1         = &min_sched_granularity_ns,
 330                 .extra2         = &max_sched_granularity_ns,
 331         },
 332         {
 333                 .procname       = "sched_wakeup_granularity_ns",
 334                 .data           = &sysctl_sched_wakeup_granularity,
 335                 .maxlen         = sizeof(unsigned int),
 336                 .mode           = 0644,
 337                 .proc_handler   = sched_proc_update_handler,
 338                 .extra1         = &min_wakeup_granularity_ns,
 339                 .extra2         = &max_wakeup_granularity_ns,
 340         },
 341 #ifdef CONFIG_SMP
 342         {
 343                 .procname       = "sched_tunable_scaling",
 344                 .data           = &sysctl_sched_tunable_scaling,
 345                 .maxlen         = sizeof(enum sched_tunable_scaling),
 346                 .mode           = 0644,
 347                 .proc_handler   = sched_proc_update_handler,
 348                 .extra1         = &min_sched_tunable_scaling,
 349                 .extra2         = &max_sched_tunable_scaling,
 350         },
 351         {
 352                 .procname       = "sched_migration_cost_ns",
 353                 .data           = &sysctl_sched_migration_cost,
 354                 .maxlen         = sizeof(unsigned int),
 355                 .mode           = 0644,
 356                 .proc_handler   = proc_dointvec,
 357         },
 358         {
 359                 .procname       = "sched_nr_migrate",
 360                 .data           = &sysctl_sched_nr_migrate,
 361                 .maxlen         = sizeof(unsigned int),
 362                 .mode           = 0644,
 363                 .proc_handler   = proc_dointvec,
 364         },
 365         {
 366                 .procname       = "sched_time_avg_ms",
 367                 .data           = &sysctl_sched_time_avg,
 368                 .maxlen         = sizeof(unsigned int),
 369                 .mode           = 0644,
 370                 .proc_handler   = proc_dointvec_minmax,
 371                 .extra1         = &one,
 372         },
 373 #ifdef CONFIG_SCHEDSTATS
 374         {
 375                 .procname       = "sched_schedstats",
 376                 .data           = NULL,
 377                 .maxlen         = sizeof(unsigned int),
 378                 .mode           = 0644,
 379                 .proc_handler   = sysctl_schedstats,
 380                 .extra1         = &zero,
 381                 .extra2         = &one,
 382         },
 383 #endif /* CONFIG_SCHEDSTATS */
 384 #endif /* CONFIG_SMP */
 385 #ifdef CONFIG_NUMA_BALANCING
 386         {
 387                 .procname       = "numa_balancing_scan_delay_ms",
 388                 .data           = &sysctl_numa_balancing_scan_delay,
 389                 .maxlen         = sizeof(unsigned int),
 390                 .mode           = 0644,
 391                 .proc_handler   = proc_dointvec,
 392         },
 393         {
 394                 .procname       = "numa_balancing_scan_period_min_ms",
 395                 .data           = &sysctl_numa_balancing_scan_period_min,
 396                 .maxlen         = sizeof(unsigned int),
 397                 .mode           = 0644,
 398                 .proc_handler   = proc_dointvec,
 399         },
 400         {
 401                 .procname       = "numa_balancing_scan_period_max_ms",
 402                 .data           = &sysctl_numa_balancing_scan_period_max,
 403                 .maxlen         = sizeof(unsigned int),
 404                 .mode           = 0644,
 405                 .proc_handler   = proc_dointvec,
 406         },
 407         {
 408                 .procname       = "numa_balancing_scan_size_mb",
 409                 .data           = &sysctl_numa_balancing_scan_size,
 410                 .maxlen         = sizeof(unsigned int),
 411                 .mode           = 0644,
 412                 .proc_handler   = proc_dointvec_minmax,
 413                 .extra1         = &one,
 414         },
 415         {
 416                 .procname       = "numa_balancing",
 417                 .data           = NULL, /* filled in by handler */
 418                 .maxlen         = sizeof(unsigned int),
 419                 .mode           = 0644,
 420                 .proc_handler   = sysctl_numa_balancing,
 421                 .extra1         = &zero,
 422                 .extra2         = &one,
 423         },
 424 #endif /* CONFIG_NUMA_BALANCING */
 425 #endif /* CONFIG_SCHED_DEBUG */
 426         {
 427                 .procname       = "sched_rt_period_us",
 428                 .data           = &sysctl_sched_rt_period,
 429                 .maxlen         = sizeof(unsigned int),
 430                 .mode           = 0644,
 431                 .proc_handler   = sched_rt_handler,
 432         },
 433         {
 434                 .procname       = "sched_rt_runtime_us",
 435                 .data           = &sysctl_sched_rt_runtime,
 436                 .maxlen         = sizeof(int),
 437                 .mode           = 0644,
 438                 .proc_handler   = sched_rt_handler,
 439         },
 440         {
 441                 .procname       = "sched_rr_timeslice_ms",
 442                 .data           = &sysctl_sched_rr_timeslice,
 443                 .maxlen         = sizeof(int),
 444                 .mode           = 0644,
 445                 .proc_handler   = sched_rr_handler,
 446         },
 447 #ifdef CONFIG_SCHED_AUTOGROUP
 448         {
 449                 .procname       = "sched_autogroup_enabled",
 450                 .data           = &sysctl_sched_autogroup_enabled,
 451                 .maxlen         = sizeof(unsigned int),
 452                 .mode           = 0644,
 453                 .proc_handler   = proc_dointvec_minmax,
 454                 .extra1         = &zero,
 455                 .extra2         = &one,
 456         },
 457 #endif
 458 #ifdef CONFIG_CFS_BANDWIDTH
 459         {
 460                 .procname       = "sched_cfs_bandwidth_slice_us",
 461                 .data           = &sysctl_sched_cfs_bandwidth_slice,
 462                 .maxlen         = sizeof(unsigned int),
 463                 .mode           = 0644,
 464                 .proc_handler   = proc_dointvec_minmax,
 465                 .extra1         = &one,
 466         },
 467 #endif
 468 #ifdef CONFIG_PROVE_LOCKING
 469         {
 470                 .procname       = "prove_locking",
 471                 .data           = &prove_locking,
 472                 .maxlen         = sizeof(int),
 473                 .mode           = 0644,
 474                 .proc_handler   = proc_dointvec,
 475         },
 476 #endif
 477 #ifdef CONFIG_LOCK_STAT
 478         {
 479                 .procname       = "lock_stat",
 480                 .data           = &lock_stat,
 481                 .maxlen         = sizeof(int),
 482                 .mode           = 0644,
 483                 .proc_handler   = proc_dointvec,
 484         },
 485 #endif
 486         {
 487                 .procname       = "panic",
 488                 .data           = &panic_timeout,
 489                 .maxlen         = sizeof(int),
 490                 .mode           = 0644,
 491                 .proc_handler   = proc_dointvec,
 492         },
 493 #ifdef CONFIG_COREDUMP
 494         {
 495                 .procname       = "core_uses_pid",
 496                 .data           = &core_uses_pid,
 497                 .maxlen         = sizeof(int),
 498                 .mode           = 0644,
 499                 .proc_handler   = proc_dointvec,
 500         },
 501         {
 502                 .procname       = "core_pattern",
 503                 .data           = core_pattern,
 504                 .maxlen         = CORENAME_MAX_SIZE,
 505                 .mode           = 0644,
 506                 .proc_handler   = proc_dostring_coredump,
 507         },
 508         {
 509                 .procname       = "core_pipe_limit",
 510                 .data           = &core_pipe_limit,
 511                 .maxlen         = sizeof(unsigned int),
 512                 .mode           = 0644,
 513                 .proc_handler   = proc_dointvec,
 514         },
 515 #endif
 516 #ifdef CONFIG_PROC_SYSCTL
 517         {
 518                 .procname       = "tainted",
 519                 .maxlen         = sizeof(long),
 520                 .mode           = 0644,
 521                 .proc_handler   = proc_taint,
 522         },
 523         {
 524                 .procname       = "sysctl_writes_strict",
 525                 .data           = &sysctl_writes_strict,
 526                 .maxlen         = sizeof(int),
 527                 .mode           = 0644,
 528                 .proc_handler   = proc_dointvec_minmax,
 529                 .extra1         = &neg_one,
 530                 .extra2         = &one,
 531         },
 532 #endif
 533 #ifdef CONFIG_LATENCYTOP
 534         {
 535                 .procname       = "latencytop",
 536                 .data           = &latencytop_enabled,
 537                 .maxlen         = sizeof(int),
 538                 .mode           = 0644,
 539                 .proc_handler   = sysctl_latencytop,
 540         },
 541 #endif
 542 #ifdef CONFIG_BLK_DEV_INITRD
 543         {
 544                 .procname       = "real-root-dev",
 545                 .data           = &real_root_dev,
 546                 .maxlen         = sizeof(int),
 547                 .mode           = 0644,
 548                 .proc_handler   = proc_dointvec,
 549         },
 550 #endif
 551         {
 552                 .procname       = "print-fatal-signals",
 553                 .data           = &print_fatal_signals,
 554                 .maxlen         = sizeof(int),
 555                 .mode           = 0644,
 556                 .proc_handler   = proc_dointvec,
 557         },
 558 #ifdef CONFIG_SPARC
 559         {
 560                 .procname       = "reboot-cmd",
 561                 .data           = reboot_command,
 562                 .maxlen         = 256,
 563                 .mode           = 0644,
 564                 .proc_handler   = proc_dostring,
 565         },
 566         {
 567                 .procname       = "stop-a",
 568                 .data           = &stop_a_enabled,
 569                 .maxlen         = sizeof (int),
 570                 .mode           = 0644,
 571                 .proc_handler   = proc_dointvec,
 572         },
 573         {
 574                 .procname       = "scons-poweroff",
 575                 .data           = &scons_pwroff,
 576                 .maxlen         = sizeof (int),
 577                 .mode           = 0644,
 578                 .proc_handler   = proc_dointvec,
 579         },
 580 #endif
 581 #ifdef CONFIG_SPARC64
 582         {
 583                 .procname       = "tsb-ratio",
 584                 .data           = &sysctl_tsb_ratio,
 585                 .maxlen         = sizeof (int),
 586                 .mode           = 0644,
 587                 .proc_handler   = proc_dointvec,
 588         },
 589 #endif
 590 #ifdef __hppa__
 591         {
 592                 .procname       = "soft-power",
 593                 .data           = &pwrsw_enabled,
 594                 .maxlen         = sizeof (int),
 595                 .mode           = 0644,
 596                 .proc_handler   = proc_dointvec,
 597         },
 598 #endif
 599 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
 600         {
 601                 .procname       = "unaligned-trap",
 602                 .data           = &unaligned_enabled,
 603                 .maxlen         = sizeof (int),
 604                 .mode           = 0644,
 605                 .proc_handler   = proc_dointvec,
 606         },
 607 #endif
 608         {
 609                 .procname       = "ctrl-alt-del",
 610                 .data           = &C_A_D,
 611                 .maxlen         = sizeof(int),
 612                 .mode           = 0644,
 613                 .proc_handler   = proc_dointvec,
 614         },
 615 #ifdef CONFIG_FUNCTION_TRACER
 616         {
 617                 .procname       = "ftrace_enabled",
 618                 .data           = &ftrace_enabled,
 619                 .maxlen         = sizeof(int),
 620                 .mode           = 0644,
 621                 .proc_handler   = ftrace_enable_sysctl,
 622         },
 623 #endif
 624 #ifdef CONFIG_STACK_TRACER
 625         {
 626                 .procname       = "stack_tracer_enabled",
 627                 .data           = &stack_tracer_enabled,
 628                 .maxlen         = sizeof(int),
 629                 .mode           = 0644,
 630                 .proc_handler   = stack_trace_sysctl,
 631         },
 632 #endif
 633 #ifdef CONFIG_TRACING
 634         {
 635                 .procname       = "ftrace_dump_on_oops",
 636                 .data           = &ftrace_dump_on_oops,
 637                 .maxlen         = sizeof(int),
 638                 .mode           = 0644,
 639                 .proc_handler   = proc_dointvec,
 640         },
 641         {
 642                 .procname       = "traceoff_on_warning",
 643                 .data           = &__disable_trace_on_warning,
 644                 .maxlen         = sizeof(__disable_trace_on_warning),
 645                 .mode           = 0644,
 646                 .proc_handler   = proc_dointvec,
 647         },
 648         {
 649                 .procname       = "tracepoint_printk",
 650                 .data           = &tracepoint_printk,
 651                 .maxlen         = sizeof(tracepoint_printk),
 652                 .mode           = 0644,
 653                 .proc_handler   = tracepoint_printk_sysctl,
 654         },
 655 #endif
 656 #ifdef CONFIG_KEXEC_CORE
 657         {
 658                 .procname       = "kexec_load_disabled",
 659                 .data           = &kexec_load_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_MODULES
 669         {
 670                 .procname       = "modprobe",
 671                 .data           = &modprobe_path,
 672                 .maxlen         = KMOD_PATH_LEN,
 673                 .mode           = 0644,
 674                 .proc_handler   = proc_dostring,
 675         },
 676         {
 677                 .procname       = "modules_disabled",
 678                 .data           = &modules_disabled,
 679                 .maxlen         = sizeof(int),
 680                 .mode           = 0644,
 681                 /* only handle a transition from default "0" to "1" */
 682                 .proc_handler   = proc_dointvec_minmax,
 683                 .extra1         = &one,
 684                 .extra2         = &one,
 685         },
 686 #endif
 687 #ifdef CONFIG_UEVENT_HELPER
 688         {
 689                 .procname       = "hotplug",
 690                 .data           = &uevent_helper,
 691                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 692                 .mode           = 0644,
 693                 .proc_handler   = proc_dostring,
 694         },
 695 #endif
 696 #ifdef CONFIG_CHR_DEV_SG
 697         {
 698                 .procname       = "sg-big-buff",
 699                 .data           = &sg_big_buff,
 700                 .maxlen         = sizeof (int),
 701                 .mode           = 0444,
 702                 .proc_handler   = proc_dointvec,
 703         },
 704 #endif
 705 #ifdef CONFIG_BSD_PROCESS_ACCT
 706         {
 707                 .procname       = "acct",
 708                 .data           = &acct_parm,
 709                 .maxlen         = 3*sizeof(int),
 710                 .mode           = 0644,
 711                 .proc_handler   = proc_dointvec,
 712         },
 713 #endif
 714 #ifdef CONFIG_MAGIC_SYSRQ
 715         {
 716                 .procname       = "sysrq",
 717                 .data           = &__sysrq_enabled,
 718                 .maxlen         = sizeof (int),
 719                 .mode           = 0644,
 720                 .proc_handler   = sysrq_sysctl_handler,
 721         },
 722 #endif
 723 #ifdef CONFIG_PROC_SYSCTL
 724         {
 725                 .procname       = "cad_pid",
 726                 .data           = NULL,
 727                 .maxlen         = sizeof (int),
 728                 .mode           = 0600,
 729                 .proc_handler   = proc_do_cad_pid,
 730         },
 731 #endif
 732         {
 733                 .procname       = "threads-max",
 734                 .data           = NULL,
 735                 .maxlen         = sizeof(int),
 736                 .mode           = 0644,
 737                 .proc_handler   = sysctl_max_threads,
 738         },
 739         {
 740                 .procname       = "random",
 741                 .mode           = 0555,
 742                 .child          = random_table,
 743         },
 744         {
 745                 .procname       = "usermodehelper",
 746                 .mode           = 0555,
 747                 .child          = usermodehelper_table,
 748         },
 749         {
 750                 .procname       = "overflowuid",
 751                 .data           = &overflowuid,
 752                 .maxlen         = sizeof(int),
 753                 .mode           = 0644,
 754                 .proc_handler   = proc_dointvec_minmax,
 755                 .extra1         = &minolduid,
 756                 .extra2         = &maxolduid,
 757         },
 758         {
 759                 .procname       = "overflowgid",
 760                 .data           = &overflowgid,
 761                 .maxlen         = sizeof(int),
 762                 .mode           = 0644,
 763                 .proc_handler   = proc_dointvec_minmax,
 764                 .extra1         = &minolduid,
 765                 .extra2         = &maxolduid,
 766         },
 767 #ifdef CONFIG_S390
 768 #ifdef CONFIG_MATHEMU
 769         {
 770                 .procname       = "ieee_emulation_warnings",
 771                 .data           = &sysctl_ieee_emulation_warnings,
 772                 .maxlen         = sizeof(int),
 773                 .mode           = 0644,
 774                 .proc_handler   = proc_dointvec,
 775         },
 776 #endif
 777         {
 778                 .procname       = "userprocess_debug",
 779                 .data           = &show_unhandled_signals,
 780                 .maxlen         = sizeof(int),
 781                 .mode           = 0644,
 782                 .proc_handler   = proc_dointvec,
 783         },
 784 #endif
 785         {
 786                 .procname       = "pid_max",
 787                 .data           = &pid_max,
 788                 .maxlen         = sizeof (int),
 789                 .mode           = 0644,
 790                 .proc_handler   = proc_dointvec_minmax,
 791                 .extra1         = &pid_max_min,
 792                 .extra2         = &pid_max_max,
 793         },
 794         {
 795                 .procname       = "panic_on_oops",
 796                 .data           = &panic_on_oops,
 797                 .maxlen         = sizeof(int),
 798                 .mode           = 0644,
 799                 .proc_handler   = proc_dointvec,
 800         },
 801 #if defined CONFIG_PRINTK
 802         {
 803                 .procname       = "printk",
 804                 .data           = &console_loglevel,
 805                 .maxlen         = 4*sizeof(int),
 806                 .mode           = 0644,
 807                 .proc_handler   = proc_dointvec,
 808         },
 809         {
 810                 .procname       = "printk_ratelimit",
 811                 .data           = &printk_ratelimit_state.interval,
 812                 .maxlen         = sizeof(int),
 813                 .mode           = 0644,
 814                 .proc_handler   = proc_dointvec_jiffies,
 815         },
 816         {
 817                 .procname       = "printk_ratelimit_burst",
 818                 .data           = &printk_ratelimit_state.burst,
 819                 .maxlen         = sizeof(int),
 820                 .mode           = 0644,
 821                 .proc_handler   = proc_dointvec,
 822         },
 823         {
 824                 .procname       = "printk_delay",
 825                 .data           = &printk_delay_msec,
 826                 .maxlen         = sizeof(int),
 827                 .mode           = 0644,
 828                 .proc_handler   = proc_dointvec_minmax,
 829                 .extra1         = &zero,
 830                 .extra2         = &ten_thousand,
 831         },
 832         {
 833                 .procname       = "printk_devkmsg",
 834                 .data           = devkmsg_log_str,
 835                 .maxlen         = DEVKMSG_STR_MAX_SIZE,
 836                 .mode           = 0644,
 837                 .proc_handler   = devkmsg_sysctl_set_loglvl,
 838         },
 839         {
 840                 .procname       = "dmesg_restrict",
 841                 .data           = &dmesg_restrict,
 842                 .maxlen         = sizeof(int),
 843                 .mode           = 0644,
 844                 .proc_handler   = proc_dointvec_minmax_sysadmin,
 845                 .extra1         = &zero,
 846                 .extra2         = &one,
 847         },
 848         {
 849                 .procname       = "kptr_restrict",
 850                 .data           = &kptr_restrict,
 851                 .maxlen         = sizeof(int),
 852                 .mode           = 0644,
 853                 .proc_handler   = proc_dointvec_minmax_sysadmin,
 854                 .extra1         = &zero,
 855                 .extra2         = &two,
 856         },
 857 #endif
 858         {
 859                 .procname       = "ngroups_max",
 860                 .data           = &ngroups_max,
 861                 .maxlen         = sizeof (int),
 862                 .mode           = 0444,
 863                 .proc_handler   = proc_dointvec,
 864         },
 865         {
 866                 .procname       = "cap_last_cap",
 867                 .data           = (void *)&cap_last_cap,
 868                 .maxlen         = sizeof(int),
 869                 .mode           = 0444,
 870                 .proc_handler   = proc_dointvec,
 871         },
 872 #if defined(CONFIG_LOCKUP_DETECTOR)
 873         {
 874                 .procname       = "watchdog",
 875                 .data           = &watchdog_user_enabled,
 876                 .maxlen         = sizeof(int),
 877                 .mode           = 0644,
 878                 .proc_handler   = proc_watchdog,
 879                 .extra1         = &zero,
 880                 .extra2         = &one,
 881         },
 882         {
 883                 .procname       = "watchdog_thresh",
 884                 .data           = &watchdog_thresh,
 885                 .maxlen         = sizeof(int),
 886                 .mode           = 0644,
 887                 .proc_handler   = proc_watchdog_thresh,
 888                 .extra1         = &zero,
 889                 .extra2         = &sixty,
 890         },
 891         {
 892                 .procname       = "nmi_watchdog",
 893                 .data           = &nmi_watchdog_user_enabled,
 894                 .maxlen         = sizeof(int),
 895                 .mode           = NMI_WATCHDOG_SYSCTL_PERM,
 896                 .proc_handler   = proc_nmi_watchdog,
 897                 .extra1         = &zero,
 898                 .extra2         = &one,
 899         },
 900         {
 901                 .procname       = "watchdog_cpumask",
 902                 .data           = &watchdog_cpumask_bits,
 903                 .maxlen         = NR_CPUS,
 904                 .mode           = 0644,
 905                 .proc_handler   = proc_watchdog_cpumask,
 906         },
 907 #ifdef CONFIG_SOFTLOCKUP_DETECTOR
 908         {
 909                 .procname       = "soft_watchdog",
 910                 .data           = &soft_watchdog_user_enabled,
 911                 .maxlen         = sizeof(int),
 912                 .mode           = 0644,
 913                 .proc_handler   = proc_soft_watchdog,
 914                 .extra1         = &zero,
 915                 .extra2         = &one,
 916         },
 917         {
 918                 .procname       = "softlockup_panic",
 919                 .data           = &softlockup_panic,
 920                 .maxlen         = sizeof(int),
 921                 .mode           = 0644,
 922                 .proc_handler   = proc_dointvec_minmax,
 923                 .extra1         = &zero,
 924                 .extra2         = &one,
 925         },
 926 #ifdef CONFIG_SMP
 927         {
 928                 .procname       = "softlockup_all_cpu_backtrace",
 929                 .data           = &sysctl_softlockup_all_cpu_backtrace,
 930                 .maxlen         = sizeof(int),
 931                 .mode           = 0644,
 932                 .proc_handler   = proc_dointvec_minmax,
 933                 .extra1         = &zero,
 934                 .extra2         = &one,
 935         },
 936 #endif /* CONFIG_SMP */
 937 #endif
 938 #ifdef CONFIG_HARDLOCKUP_DETECTOR
 939         {
 940                 .procname       = "hardlockup_panic",
 941                 .data           = &hardlockup_panic,
 942                 .maxlen         = sizeof(int),
 943                 .mode           = 0644,
 944                 .proc_handler   = proc_dointvec_minmax,
 945                 .extra1         = &zero,
 946                 .extra2         = &one,
 947         },
 948 #ifdef CONFIG_SMP
 949         {
 950                 .procname       = "hardlockup_all_cpu_backtrace",
 951                 .data           = &sysctl_hardlockup_all_cpu_backtrace,
 952                 .maxlen         = sizeof(int),
 953                 .mode           = 0644,
 954                 .proc_handler   = proc_dointvec_minmax,
 955                 .extra1         = &zero,
 956                 .extra2         = &one,
 957         },
 958 #endif /* CONFIG_SMP */
 959 #endif
 960 #endif
 961
 962 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 963         {
 964                 .procname       = "unknown_nmi_panic",
 965                 .data           = &unknown_nmi_panic,
 966                 .maxlen         = sizeof (int),
 967                 .mode           = 0644,
 968                 .proc_handler   = proc_dointvec,
 969         },
 970 #endif
 971 #if defined(CONFIG_X86)
 972         {
 973                 .procname       = "panic_on_unrecovered_nmi",
 974                 .data           = &panic_on_unrecovered_nmi,
 975                 .maxlen         = sizeof(int),
 976                 .mode           = 0644,
 977                 .proc_handler   = proc_dointvec,
 978         },
 979         {
 980                 .procname       = "panic_on_io_nmi",
 981                 .data           = &panic_on_io_nmi,
 982                 .maxlen         = sizeof(int),
 983                 .mode           = 0644,
 984                 .proc_handler   = proc_dointvec,
 985         },
 986 #ifdef CONFIG_DEBUG_STACKOVERFLOW
 987         {
 988                 .procname       = "panic_on_stackoverflow",
 989                 .data           = &sysctl_panic_on_stackoverflow,
 990                 .maxlen         = sizeof(int),
 991                 .mode           = 0644,
 992                 .proc_handler   = proc_dointvec,
 993         },
 994 #endif
 995         {
 996                 .procname       = "bootloader_type",
 997                 .data           = &bootloader_type,
 998                 .maxlen         = sizeof (int),
 999                 .mode           = 0444,
1000                 .proc_handler   = proc_dointvec,
1001         },
1002         {
1003                 .procname       = "bootloader_version",
1004                 .data           = &bootloader_version,
1005                 .maxlen         = sizeof (int),
1006                 .mode           = 0444,
1007                 .proc_handler   = proc_dointvec,
1008         },
1009         {
1010                 .procname       = "io_delay_type",
1011                 .data           = &io_delay_type,
1012                 .maxlen         = sizeof(int),
1013                 .mode           = 0644,
1014                 .proc_handler   = proc_dointvec,
1015         },
1016 #endif
1017 #if defined(CONFIG_MMU)
1018         {
1019                 .procname       = "randomize_va_space",
1020                 .data           = &randomize_va_space,
1021                 .maxlen         = sizeof(int),
1022                 .mode           = 0644,
1023                 .proc_handler   = proc_dointvec,
1024         },
1025 #endif
1026 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1027         {
1028                 .procname       = "spin_retry",
1029                 .data           = &spin_retry,
1030                 .maxlen         = sizeof (int),
1031                 .mode           = 0644,
1032                 .proc_handler   = proc_dointvec,
1033         },
1034 #endif
1035 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1036         {
1037                 .procname       = "acpi_video_flags",
1038                 .data           = &acpi_realmode_flags,
1039                 .maxlen         = sizeof (unsigned long),
1040                 .mode           = 0644,
1041                 .proc_handler   = proc_doulongvec_minmax,
1042         },
1043 #endif
1044 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1045         {
1046                 .procname       = "ignore-unaligned-usertrap",
1047                 .data           = &no_unaligned_warning,
1048                 .maxlen         = sizeof (int),
1049                 .mode           = 0644,
1050                 .proc_handler   = proc_dointvec,
1051         },
1052 #endif
1053 #ifdef CONFIG_IA64
1054         {
1055                 .procname       = "unaligned-dump-stack",
1056                 .data           = &unaligned_dump_stack,
1057                 .maxlen         = sizeof (int),
1058                 .mode           = 0644,
1059                 .proc_handler   = proc_dointvec,
1060         },
1061 #endif
1062 #ifdef CONFIG_DETECT_HUNG_TASK
1063         {
1064                 .procname       = "hung_task_panic",
1065                 .data           = &sysctl_hung_task_panic,
1066                 .maxlen         = sizeof(int),
1067                 .mode           = 0644,
1068                 .proc_handler   = proc_dointvec_minmax,
1069                 .extra1         = &zero,
1070                 .extra2         = &one,
1071         },
1072         {
1073                 .procname       = "hung_task_check_count",
1074                 .data           = &sysctl_hung_task_check_count,
1075                 .maxlen         = sizeof(int),
1076                 .mode           = 0644,
1077                 .proc_handler   = proc_dointvec_minmax,
1078                 .extra1         = &zero,
1079         },
1080         {
1081                 .procname       = "hung_task_timeout_secs",
1082                 .data           = &sysctl_hung_task_timeout_secs,
1083                 .maxlen         = sizeof(unsigned long),
1084                 .mode           = 0644,
1085                 .proc_handler   = proc_dohung_task_timeout_secs,
1086                 .extra2         = &hung_task_timeout_max,
1087         },
1088         {
1089                 .procname       = "hung_task_warnings",
1090                 .data           = &sysctl_hung_task_warnings,
1091                 .maxlen         = sizeof(int),
1092                 .mode           = 0644,
1093                 .proc_handler   = proc_dointvec_minmax,
1094                 .extra1         = &neg_one,
1095         },
1096 #endif
1097 #ifdef CONFIG_RT_MUTEXES
1098         {
1099                 .procname       = "max_lock_depth",
1100                 .data           = &max_lock_depth,
1101                 .maxlen         = sizeof(int),
1102                 .mode           = 0644,
1103                 .proc_handler   = proc_dointvec,
1104         },
1105 #endif
1106         {
1107                 .procname       = "poweroff_cmd",
1108                 .data           = &poweroff_cmd,
1109                 .maxlen         = POWEROFF_CMD_PATH_LEN,
1110                 .mode           = 0644,
1111                 .proc_handler   = proc_dostring,
1112         },
1113 #ifdef CONFIG_KEYS
1114         {
1115                 .procname       = "keys",
1116                 .mode           = 0555,
1117                 .child          = key_sysctls,
1118         },
1119 #endif
1120 #ifdef CONFIG_PERF_EVENTS
1121         /*
1122          * User-space scripts rely on the existence of this file
1123          * as a feature check for perf_events being enabled.
1124          *
1125          * So it's an ABI, do not remove!
1126          */
1127         {
1128                 .procname       = "perf_event_paranoid",
1129                 .data           = &sysctl_perf_event_paranoid,
1130                 .maxlen         = sizeof(sysctl_perf_event_paranoid),
1131                 .mode           = 0644,
1132                 .proc_handler   = proc_dointvec,
1133         },
1134         {
1135                 .procname       = "perf_event_mlock_kb",
1136                 .data           = &sysctl_perf_event_mlock,
1137                 .maxlen         = sizeof(sysctl_perf_event_mlock),
1138                 .mode           = 0644,
1139                 .proc_handler   = proc_dointvec,
1140         },
1141         {
1142                 .procname       = "perf_event_max_sample_rate",
1143                 .data           = &sysctl_perf_event_sample_rate,
1144                 .maxlen         = sizeof(sysctl_perf_event_sample_rate),
1145                 .mode           = 0644,
1146                 .proc_handler   = perf_proc_update_handler,
1147                 .extra1         = &one,
1148         },
1149         {
1150                 .procname       = "perf_cpu_time_max_percent",
1151                 .data           = &sysctl_perf_cpu_time_max_percent,
1152                 .maxlen         = sizeof(sysctl_perf_cpu_time_max_percent),
1153                 .mode           = 0644,
1154                 .proc_handler   = perf_cpu_time_max_percent_handler,
1155                 .extra1         = &zero,
1156                 .extra2         = &one_hundred,
1157         },
1158         {
1159                 .procname       = "perf_event_max_stack",
1160                 .data           = &sysctl_perf_event_max_stack,
1161                 .maxlen         = sizeof(sysctl_perf_event_max_stack),
1162                 .mode           = 0644,
1163                 .proc_handler   = perf_event_max_stack_handler,
1164                 .extra1         = &zero,
1165                 .extra2         = &six_hundred_forty_kb,
1166         },
1167         {
1168                 .procname       = "perf_event_max_contexts_per_stack",
1169                 .data           = &sysctl_perf_event_max_contexts_per_stack,
1170                 .maxlen         = sizeof(sysctl_perf_event_max_contexts_per_stack),
1171                 .mode           = 0644,
1172                 .proc_handler   = perf_event_max_stack_handler,
1173                 .extra1         = &zero,
1174                 .extra2         = &one_thousand,
1175         },
1176 #endif
1177         {
1178                 .procname       = "panic_on_warn",
1179                 .data           = &panic_on_warn,
1180                 .maxlen         = sizeof(int),
1181                 .mode           = 0644,
1182                 .proc_handler   = proc_dointvec_minmax,
1183                 .extra1         = &zero,
1184                 .extra2         = &one,
1185         },
1186 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1187         {
1188                 .procname       = "timer_migration",
1189                 .data           = &sysctl_timer_migration,
1190                 .maxlen         = sizeof(unsigned int),
1191                 .mode           = 0644,
1192                 .proc_handler   = timer_migration_handler,
1193                 .extra1         = &zero,
1194                 .extra2         = &one,
1195         },
1196 #endif
1197 #ifdef CONFIG_BPF_SYSCALL
1198         {
1199                 .procname       = "unprivileged_bpf_disabled",
1200                 .data           = &sysctl_unprivileged_bpf_disabled,
1201                 .maxlen         = sizeof(sysctl_unprivileged_bpf_disabled),
1202                 .mode           = 0644,
1203                 /* only handle a transition from default "0" to "1" */
1204                 .proc_handler   = proc_dointvec_minmax,
1205                 .extra1         = &one,
1206                 .extra2         = &one,
1207         },
1208 #endif
1209 #if defined(CONFIG_TREE_RCU) || defined(CONFIG_PREEMPT_RCU)
1210         {
1211                 .procname       = "panic_on_rcu_stall",
1212                 .data           = &sysctl_panic_on_rcu_stall,
1213                 .maxlen         = sizeof(sysctl_panic_on_rcu_stall),
1214                 .mode           = 0644,
1215                 .proc_handler   = proc_dointvec_minmax,
1216                 .extra1         = &zero,
1217                 .extra2         = &one,
1218         },
1219 #endif
1220         { }
1221 };
1222
1223 static struct ctl_table vm_table[] = {
1224         {
1225                 .procname       = "overcommit_memory",
1226                 .data           = &sysctl_overcommit_memory,
1227                 .maxlen         = sizeof(sysctl_overcommit_memory),
1228                 .mode           = 0644,
1229                 .proc_handler   = proc_dointvec_minmax,
1230                 .extra1         = &zero,
1231                 .extra2         = &two,
1232         },
1233         {
1234                 .procname       = "panic_on_oom",
1235                 .data           = &sysctl_panic_on_oom,
1236                 .maxlen         = sizeof(sysctl_panic_on_oom),
1237                 .mode           = 0644,
1238                 .proc_handler   = proc_dointvec_minmax,
1239                 .extra1         = &zero,
1240                 .extra2         = &two,
1241         },
1242         {
1243                 .procname       = "oom_kill_allocating_task",
1244                 .data           = &sysctl_oom_kill_allocating_task,
1245                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
1246                 .mode           = 0644,
1247                 .proc_handler   = proc_dointvec,
1248         },
1249         {
1250                 .procname       = "oom_dump_tasks",
1251                 .data           = &sysctl_oom_dump_tasks,
1252                 .maxlen         = sizeof(sysctl_oom_dump_tasks),
1253                 .mode           = 0644,
1254                 .proc_handler   = proc_dointvec,
1255         },
1256         {
1257                 .procname       = "overcommit_ratio",
1258                 .data           = &sysctl_overcommit_ratio,
1259                 .maxlen         = sizeof(sysctl_overcommit_ratio),
1260                 .mode           = 0644,
1261                 .proc_handler   = overcommit_ratio_handler,
1262         },
1263         {
1264                 .procname       = "overcommit_kbytes",
1265                 .data           = &sysctl_overcommit_kbytes,
1266                 .maxlen         = sizeof(sysctl_overcommit_kbytes),
1267                 .mode           = 0644,
1268                 .proc_handler   = overcommit_kbytes_handler,
1269         },
1270         {
1271                 .procname       = "page-cluster",
1272                 .data           = &page_cluster,
1273                 .maxlen         = sizeof(int),
1274                 .mode           = 0644,
1275                 .proc_handler   = proc_dointvec_minmax,
1276                 .extra1         = &zero,
1277         },
1278         {
1279                 .procname       = "dirty_background_ratio",
1280                 .data           = &dirty_background_ratio,
1281                 .maxlen         = sizeof(dirty_background_ratio),
1282                 .mode           = 0644,
1283                 .proc_handler   = dirty_background_ratio_handler,
1284                 .extra1         = &zero,
1285                 .extra2         = &one_hundred,
1286         },
1287         {
1288                 .procname       = "dirty_background_bytes",
1289                 .data           = &dirty_background_bytes,
1290                 .maxlen         = sizeof(dirty_background_bytes),
1291                 .mode           = 0644,
1292                 .proc_handler   = dirty_background_bytes_handler,
1293                 .extra1         = &one_ul,
1294         },
1295         {
1296                 .procname       = "dirty_ratio",
1297                 .data           = &vm_dirty_ratio,
1298                 .maxlen         = sizeof(vm_dirty_ratio),
1299                 .mode           = 0644,
1300                 .proc_handler   = dirty_ratio_handler,
1301                 .extra1         = &zero,
1302                 .extra2         = &one_hundred,
1303         },
1304         {
1305                 .procname       = "dirty_bytes",
1306                 .data           = &vm_dirty_bytes,
1307                 .maxlen         = sizeof(vm_dirty_bytes),
1308                 .mode           = 0644,
1309                 .proc_handler   = dirty_bytes_handler,
1310                 .extra1         = &dirty_bytes_min,
1311         },
1312         {
1313                 .procname       = "dirty_writeback_centisecs",
1314                 .data           = &dirty_writeback_interval,
1315                 .maxlen         = sizeof(dirty_writeback_interval),
1316                 .mode           = 0644,
1317                 .proc_handler   = dirty_writeback_centisecs_handler,
1318         },
1319         {
1320                 .procname       = "dirty_expire_centisecs",
1321                 .data           = &dirty_expire_interval,
1322                 .maxlen         = sizeof(dirty_expire_interval),
1323                 .mode           = 0644,
1324                 .proc_handler   = proc_dointvec_minmax,
1325                 .extra1         = &zero,
1326         },
1327         {
1328                 .procname       = "dirtytime_expire_seconds",
1329                 .data           = &dirtytime_expire_interval,
1330                 .maxlen         = sizeof(dirty_expire_interval),
1331                 .mode           = 0644,
1332                 .proc_handler   = dirtytime_interval_handler,
1333                 .extra1         = &zero,
1334         },
1335         {
1336                 .procname       = "swappiness",
1337                 .data           = &vm_swappiness,
1338                 .maxlen         = sizeof(vm_swappiness),
1339                 .mode           = 0644,
1340                 .proc_handler   = proc_dointvec_minmax,
1341                 .extra1         = &zero,
1342                 .extra2         = &one_hundred,
1343         },
1344 #ifdef CONFIG_HUGETLB_PAGE
1345         {
1346                 .procname       = "nr_hugepages",
1347                 .data           = NULL,
1348                 .maxlen         = sizeof(unsigned long),
1349                 .mode           = 0644,
1350                 .proc_handler   = hugetlb_sysctl_handler,
1351         },
1352 #ifdef CONFIG_NUMA
1353         {
1354                 .procname       = "nr_hugepages_mempolicy",
1355                 .data           = NULL,
1356                 .maxlen         = sizeof(unsigned long),
1357                 .mode           = 0644,
1358                 .proc_handler   = &hugetlb_mempolicy_sysctl_handler,
1359         },
1360         {
1361                 .procname               = "numa_stat",
1362                 .data                   = &sysctl_vm_numa_stat,
1363                 .maxlen                 = sizeof(int),
1364                 .mode                   = 0644,
1365                 .proc_handler   = sysctl_vm_numa_stat_handler,
1366                 .extra1                 = &zero,
1367                 .extra2                 = &one,
1368         },
1369 #endif
1370          {
1371                 .procname       = "hugetlb_shm_group",
1372                 .data           = &sysctl_hugetlb_shm_group,
1373                 .maxlen         = sizeof(gid_t),
1374                 .mode           = 0644,
1375                 .proc_handler   = proc_dointvec,
1376          },
1377         {
1378                 .procname       = "nr_overcommit_hugepages",
1379                 .data           = NULL,
1380                 .maxlen         = sizeof(unsigned long),
1381                 .mode           = 0644,
1382                 .proc_handler   = hugetlb_overcommit_handler,
1383         },
1384 #endif
1385         {
1386                 .procname       = "lowmem_reserve_ratio",
1387                 .data           = &sysctl_lowmem_reserve_ratio,
1388                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
1389                 .mode           = 0644,
1390                 .proc_handler   = lowmem_reserve_ratio_sysctl_handler,
1391         },
1392         {
1393                 .procname       = "drop_caches",
1394                 .data           = &sysctl_drop_caches,
1395                 .maxlen         = sizeof(int),
1396                 .mode           = 0644,
1397                 .proc_handler   = drop_caches_sysctl_handler,
1398                 .extra1         = &one,
1399                 .extra2         = &four,
1400         },
1401 #ifdef CONFIG_COMPACTION
1402         {
1403                 .procname       = "compact_memory",
1404                 .data           = &sysctl_compact_memory,
1405                 .maxlen         = sizeof(int),
1406                 .mode           = 0200,
1407                 .proc_handler   = sysctl_compaction_handler,
1408         },
1409         {
1410                 .procname       = "extfrag_threshold",
1411                 .data           = &sysctl_extfrag_threshold,
1412                 .maxlen         = sizeof(int),
1413                 .mode           = 0644,
1414                 .proc_handler   = sysctl_extfrag_handler,
1415                 .extra1         = &min_extfrag_threshold,
1416                 .extra2         = &max_extfrag_threshold,
1417         },
1418         {
1419                 .procname       = "compact_unevictable_allowed",
1420                 .data           = &sysctl_compact_unevictable_allowed,
1421                 .maxlen         = sizeof(int),
1422                 .mode           = 0644,
1423                 .proc_handler   = proc_dointvec,
1424                 .extra1         = &zero,
1425                 .extra2         = &one,
1426         },
1427
1428 #endif /* CONFIG_COMPACTION */
1429         {
1430                 .procname       = "min_free_kbytes",
1431                 .data           = &min_free_kbytes,
1432                 .maxlen         = sizeof(min_free_kbytes),
1433                 .mode           = 0644,
1434                 .proc_handler   = min_free_kbytes_sysctl_handler,
1435                 .extra1         = &zero,
1436         },
1437         {
1438                 .procname       = "watermark_scale_factor",
1439                 .data           = &watermark_scale_factor,
1440                 .maxlen         = sizeof(watermark_scale_factor),
1441                 .mode           = 0644,
1442                 .proc_handler   = watermark_scale_factor_sysctl_handler,
1443                 .extra1         = &one,
1444                 .extra2         = &one_thousand,
1445         },
1446         {
1447                 .procname       = "percpu_pagelist_fraction",
1448                 .data           = &percpu_pagelist_fraction,
1449                 .maxlen         = sizeof(percpu_pagelist_fraction),
1450                 .mode           = 0644,
1451                 .proc_handler   = percpu_pagelist_fraction_sysctl_handler,
1452                 .extra1         = &zero,
1453         },
1454 #ifdef CONFIG_MMU
1455         {
1456                 .procname       = "max_map_count",
1457                 .data           = &sysctl_max_map_count,
1458                 .maxlen         = sizeof(sysctl_max_map_count),
1459                 .mode           = 0644,
1460                 .proc_handler   = proc_dointvec_minmax,
1461                 .extra1         = &zero,
1462         },
1463 #else
1464         {
1465                 .procname       = "nr_trim_pages",
1466                 .data           = &sysctl_nr_trim_pages,
1467                 .maxlen         = sizeof(sysctl_nr_trim_pages),
1468                 .mode           = 0644,
1469                 .proc_handler   = proc_dointvec_minmax,
1470                 .extra1         = &zero,
1471         },
1472 #endif
1473         {
1474                 .procname       = "laptop_mode",
1475                 .data           = &laptop_mode,
1476                 .maxlen         = sizeof(laptop_mode),
1477                 .mode           = 0644,
1478                 .proc_handler   = proc_dointvec_jiffies,
1479         },
1480         {
1481                 .procname       = "block_dump",
1482                 .data           = &block_dump,
1483                 .maxlen         = sizeof(block_dump),
1484                 .mode           = 0644,
1485                 .proc_handler   = proc_dointvec,
1486                 .extra1         = &zero,
1487         },
1488         {
1489                 .procname       = "vfs_cache_pressure",
1490                 .data           = &sysctl_vfs_cache_pressure,
1491                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
1492                 .mode           = 0644,
1493                 .proc_handler   = proc_dointvec,
1494                 .extra1         = &zero,
1495         },
1496 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1497         {
1498                 .procname       = "legacy_va_layout",
1499                 .data           = &sysctl_legacy_va_layout,
1500                 .maxlen         = sizeof(sysctl_legacy_va_layout),
1501                 .mode           = 0644,
1502                 .proc_handler   = proc_dointvec,
1503                 .extra1         = &zero,
1504         },
1505 #endif
1506 #ifdef CONFIG_NUMA
1507         {
1508                 .procname       = "zone_reclaim_mode",
1509                 .data           = &node_reclaim_mode,
1510                 .maxlen         = sizeof(node_reclaim_mode),
1511                 .mode           = 0644,
1512                 .proc_handler   = proc_dointvec,
1513                 .extra1         = &zero,
1514         },
1515         {
1516                 .procname       = "min_unmapped_ratio",
1517                 .data           = &sysctl_min_unmapped_ratio,
1518                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1519                 .mode           = 0644,
1520                 .proc_handler   = sysctl_min_unmapped_ratio_sysctl_handler,
1521                 .extra1         = &zero,
1522                 .extra2         = &one_hundred,
1523         },
1524         {
1525                 .procname       = "min_slab_ratio",
1526                 .data           = &sysctl_min_slab_ratio,
1527                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1528                 .mode           = 0644,
1529                 .proc_handler   = sysctl_min_slab_ratio_sysctl_handler,
1530                 .extra1         = &zero,
1531                 .extra2         = &one_hundred,
1532         },
1533 #endif
1534 #ifdef CONFIG_SMP
1535         {
1536                 .procname       = "stat_interval",
1537                 .data           = &sysctl_stat_interval,
1538                 .maxlen         = sizeof(sysctl_stat_interval),
1539                 .mode           = 0644,
1540                 .proc_handler   = proc_dointvec_jiffies,
1541         },
1542         {
1543                 .procname       = "stat_refresh",
1544                 .data           = NULL,
1545                 .maxlen         = 0,
1546                 .mode           = 0600,
1547                 .proc_handler   = vmstat_refresh,
1548         },
1549 #endif
1550 #ifdef CONFIG_MMU
1551         {
1552                 .procname       = "mmap_min_addr",
1553                 .data           = &dac_mmap_min_addr,
1554                 .maxlen         = sizeof(unsigned long),
1555                 .mode           = 0644,
1556                 .proc_handler   = mmap_min_addr_handler,
1557         },
1558 #endif
1559 #ifdef CONFIG_NUMA
1560         {
1561                 .procname       = "numa_zonelist_order",
1562                 .data           = &numa_zonelist_order,
1563                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1564                 .mode           = 0644,
1565                 .proc_handler   = numa_zonelist_order_handler,
1566         },
1567 #endif
1568 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1569    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1570         {
1571                 .procname       = "vdso_enabled",
1572 #ifdef CONFIG_X86_32
1573                 .data           = &vdso32_enabled,
1574                 .maxlen         = sizeof(vdso32_enabled),
1575 #else
1576                 .data           = &vdso_enabled,
1577                 .maxlen         = sizeof(vdso_enabled),
1578 #endif
1579                 .mode           = 0644,
1580                 .proc_handler   = proc_dointvec,
1581                 .extra1         = &zero,
1582         },
1583 #endif
1584 #ifdef CONFIG_HIGHMEM
1585         {
1586                 .procname       = "highmem_is_dirtyable",
1587                 .data           = &vm_highmem_is_dirtyable,
1588                 .maxlen         = sizeof(vm_highmem_is_dirtyable),
1589                 .mode           = 0644,
1590                 .proc_handler   = proc_dointvec_minmax,
1591                 .extra1         = &zero,
1592                 .extra2         = &one,
1593         },
1594 #endif
1595 #ifdef CONFIG_MEMORY_FAILURE
1596         {
1597                 .procname       = "memory_failure_early_kill",
1598                 .data           = &sysctl_memory_failure_early_kill,
1599                 .maxlen         = sizeof(sysctl_memory_failure_early_kill),
1600                 .mode           = 0644,
1601                 .proc_handler   = proc_dointvec_minmax,
1602                 .extra1         = &zero,
1603                 .extra2         = &one,
1604         },
1605         {
1606                 .procname       = "memory_failure_recovery",
1607                 .data           = &sysctl_memory_failure_recovery,
1608                 .maxlen         = sizeof(sysctl_memory_failure_recovery),
1609                 .mode           = 0644,
1610                 .proc_handler   = proc_dointvec_minmax,
1611                 .extra1         = &zero,
1612                 .extra2         = &one,
1613         },
1614 #endif
1615         {
1616                 .procname       = "user_reserve_kbytes",
1617                 .data           = &sysctl_user_reserve_kbytes,
1618                 .maxlen         = sizeof(sysctl_user_reserve_kbytes),
1619                 .mode           = 0644,
1620                 .proc_handler   = proc_doulongvec_minmax,
1621         },
1622         {
1623                 .procname       = "admin_reserve_kbytes",
1624                 .data           = &sysctl_admin_reserve_kbytes,
1625                 .maxlen         = sizeof(sysctl_admin_reserve_kbytes),
1626                 .mode           = 0644,
1627                 .proc_handler   = proc_doulongvec_minmax,
1628         },
1629 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
1630         {
1631                 .procname       = "mmap_rnd_bits",
1632                 .data           = &mmap_rnd_bits,
1633                 .maxlen         = sizeof(mmap_rnd_bits),
1634                 .mode           = 0600,
1635                 .proc_handler   = proc_dointvec_minmax,
1636                 .extra1         = (void *)&mmap_rnd_bits_min,
1637                 .extra2         = (void *)&mmap_rnd_bits_max,
1638         },
1639 #endif
1640 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
1641         {
1642                 .procname       = "mmap_rnd_compat_bits",
1643                 .data           = &mmap_rnd_compat_bits,
1644                 .maxlen         = sizeof(mmap_rnd_compat_bits),
1645                 .mode           = 0600,
1646                 .proc_handler   = proc_dointvec_minmax,
1647                 .extra1         = (void *)&mmap_rnd_compat_bits_min,
1648                 .extra2         = (void *)&mmap_rnd_compat_bits_max,
1649         },
1650 #endif
1651         { }
1652 };
1653
1654 static struct ctl_table fs_table[] = {
1655         {
1656                 .procname       = "inode-nr",
1657                 .data           = &inodes_stat,
1658                 .maxlen         = 2*sizeof(long),
1659                 .mode           = 0444,
1660                 .proc_handler   = proc_nr_inodes,
1661         },
1662         {
1663                 .procname       = "inode-state",
1664                 .data           = &inodes_stat,
1665                 .maxlen         = 7*sizeof(long),
1666                 .mode           = 0444,
1667                 .proc_handler   = proc_nr_inodes,
1668         },
1669         {
1670                 .procname       = "file-nr",
1671                 .data           = &files_stat,
1672                 .maxlen         = sizeof(files_stat),
1673                 .mode           = 0444,
1674                 .proc_handler   = proc_nr_files,
1675         },
1676         {
1677                 .procname       = "file-max",
1678                 .data           = &files_stat.max_files,
1679                 .maxlen         = sizeof(files_stat.max_files),
1680                 .mode           = 0644,
1681                 .proc_handler   = proc_doulongvec_minmax,
1682         },
1683         {
1684                 .procname       = "nr_open",
1685                 .data           = &sysctl_nr_open,
1686                 .maxlen         = sizeof(unsigned int),
1687                 .mode           = 0644,
1688                 .proc_handler   = proc_dointvec_minmax,
1689                 .extra1         = &sysctl_nr_open_min,
1690                 .extra2         = &sysctl_nr_open_max,
1691         },
1692         {
1693                 .procname       = "dentry-state",
1694                 .data           = &dentry_stat,
1695                 .maxlen         = 6*sizeof(long),
1696                 .mode           = 0444,
1697                 .proc_handler   = proc_nr_dentry,
1698         },
1699         {
1700                 .procname       = "overflowuid",
1701                 .data           = &fs_overflowuid,
1702                 .maxlen         = sizeof(int),
1703                 .mode           = 0644,
1704                 .proc_handler   = proc_dointvec_minmax,
1705                 .extra1         = &minolduid,
1706                 .extra2         = &maxolduid,
1707         },
1708         {
1709                 .procname       = "overflowgid",
1710                 .data           = &fs_overflowgid,
1711                 .maxlen         = sizeof(int),
1712                 .mode           = 0644,
1713                 .proc_handler   = proc_dointvec_minmax,
1714                 .extra1         = &minolduid,
1715                 .extra2         = &maxolduid,
1716         },
1717 #ifdef CONFIG_FILE_LOCKING
1718         {
1719                 .procname       = "leases-enable",
1720                 .data           = &leases_enable,
1721                 .maxlen         = sizeof(int),
1722                 .mode           = 0644,
1723                 .proc_handler   = proc_dointvec,
1724         },
1725 #endif
1726 #ifdef CONFIG_DNOTIFY
1727         {
1728                 .procname       = "dir-notify-enable",
1729                 .data           = &dir_notify_enable,
1730                 .maxlen         = sizeof(int),
1731                 .mode           = 0644,
1732                 .proc_handler   = proc_dointvec,
1733         },
1734 #endif
1735 #ifdef CONFIG_MMU
1736 #ifdef CONFIG_FILE_LOCKING
1737         {
1738                 .procname       = "lease-break-time",
1739                 .data           = &lease_break_time,
1740                 .maxlen         = sizeof(int),
1741                 .mode           = 0644,
1742                 .proc_handler   = proc_dointvec,
1743         },
1744 #endif
1745 #ifdef CONFIG_AIO
1746         {
1747                 .procname       = "aio-nr",
1748                 .data           = &aio_nr,
1749                 .maxlen         = sizeof(aio_nr),
1750                 .mode           = 0444,
1751                 .proc_handler   = proc_doulongvec_minmax,
1752         },
1753         {
1754                 .procname       = "aio-max-nr",
1755                 .data           = &aio_max_nr,
1756                 .maxlen         = sizeof(aio_max_nr),
1757                 .mode           = 0644,
1758                 .proc_handler   = proc_doulongvec_minmax,
1759         },
1760 #endif /* CONFIG_AIO */
1761 #ifdef CONFIG_INOTIFY_USER
1762         {
1763                 .procname       = "inotify",
1764                 .mode           = 0555,
1765                 .child          = inotify_table,
1766         },
1767 #endif
1768 #ifdef CONFIG_EPOLL
1769         {
1770                 .procname       = "epoll",
1771                 .mode           = 0555,
1772                 .child          = epoll_table,
1773         },
1774 #endif
1775 #endif
1776         {
1777                 .procname       = "protected_symlinks",
1778                 .data           = &sysctl_protected_symlinks,
1779                 .maxlen         = sizeof(int),
1780                 .mode           = 0600,
1781                 .proc_handler   = proc_dointvec_minmax,
1782                 .extra1         = &zero,
1783                 .extra2         = &one,
1784         },
1785         {
1786                 .procname       = "protected_hardlinks",
1787                 .data           = &sysctl_protected_hardlinks,
1788                 .maxlen         = sizeof(int),
1789                 .mode           = 0600,
1790                 .proc_handler   = proc_dointvec_minmax,
1791                 .extra1         = &zero,
1792                 .extra2         = &one,
1793         },
1794         {
1795                 .procname       = "suid_dumpable",
1796                 .data           = &suid_dumpable,
1797                 .maxlen         = sizeof(int),
1798                 .mode           = 0644,
1799                 .proc_handler   = proc_dointvec_minmax_coredump,
1800                 .extra1         = &zero,
1801                 .extra2         = &two,
1802         },
1803 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1804         {
1805                 .procname       = "binfmt_misc",
1806                 .mode           = 0555,
1807                 .child          = sysctl_mount_point,
1808         },
1809 #endif
1810         {
1811                 .procname       = "pipe-max-size",
1812                 .data           = &pipe_max_size,
1813                 .maxlen         = sizeof(pipe_max_size),
1814                 .mode           = 0644,
1815                 .proc_handler   = &pipe_proc_fn,
1816                 .extra1         = &pipe_min_size,
1817         },
1818         {
1819                 .procname       = "pipe-user-pages-hard",
1820                 .data           = &pipe_user_pages_hard,
1821                 .maxlen         = sizeof(pipe_user_pages_hard),
1822                 .mode           = 0644,
1823                 .proc_handler   = proc_doulongvec_minmax,
1824         },
1825         {
1826                 .procname       = "pipe-user-pages-soft",
1827                 .data           = &pipe_user_pages_soft,
1828                 .maxlen         = sizeof(pipe_user_pages_soft),
1829                 .mode           = 0644,
1830                 .proc_handler   = proc_doulongvec_minmax,
1831         },
1832         {
1833                 .procname       = "mount-max",
1834                 .data           = &sysctl_mount_max,
1835                 .maxlen         = sizeof(unsigned int),
1836                 .mode           = 0644,
1837                 .proc_handler   = proc_dointvec_minmax,
1838                 .extra1         = &one,
1839         },
1840         { }
1841 };
1842
1843 static struct ctl_table debug_table[] = {
1844 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1845         {
1846                 .procname       = "exception-trace",
1847                 .data           = &show_unhandled_signals,
1848                 .maxlen         = sizeof(int),
1849                 .mode           = 0644,
1850                 .proc_handler   = proc_dointvec
1851         },
1852 #endif
1853 #if defined(CONFIG_OPTPROBES)
1854         {
1855                 .procname       = "kprobes-optimization",
1856                 .data           = &sysctl_kprobes_optimization,
1857                 .maxlen         = sizeof(int),
1858                 .mode           = 0644,
1859                 .proc_handler   = proc_kprobes_optimization_handler,
1860                 .extra1         = &zero,
1861                 .extra2         = &one,
1862         },
1863 #endif
1864         { }
1865 };
1866
1867 static struct ctl_table dev_table[] = {
1868         { }
1869 };
1870
1871 int __init sysctl_init(void)
1872 {
1873         struct ctl_table_header *hdr;
1874
1875         hdr = register_sysctl_table(sysctl_base_table);
1876         kmemleak_not_leak(hdr);
1877         return 0;
1878 }
1879
1880 #endif /* CONFIG_SYSCTL */
1881
1882 /*
1883  * /proc/sys support
1884  */
1885
1886 #ifdef CONFIG_PROC_SYSCTL
1887
1888 static int _proc_do_string(char *data, int maxlen, int write,
1889                            char __user *buffer,
1890                            size_t *lenp, loff_t *ppos)
1891 {
1892         size_t len;
1893         char __user *p;
1894         char c;
1895
1896         if (!data || !maxlen || !*lenp) {
1897                 *lenp = 0;
1898                 return 0;
1899         }
1900
1901         if (write) {
1902                 if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
1903                         /* Only continue writes not past the end of buffer. */
1904                         len = strlen(data);
1905                         if (len > maxlen - 1)
1906                                 len = maxlen - 1;
1907
1908                         if (*ppos > len)
1909                                 return 0;
1910                         len = *ppos;
1911                 } else {
1912                         /* Start writing from beginning of buffer. */
1913                         len = 0;
1914                 }
1915
1916                 *ppos += *lenp;
1917                 p = buffer;
1918                 while ((p - buffer) < *lenp && len < maxlen - 1) {
1919                         if (get_user(c, p++))
1920                                 return -EFAULT;
1921                         if (c == 0 || c == '\n')
1922                                 break;
1923                         data[len++] = c;
1924                 }
1925                 data[len] = 0;
1926         } else {
1927                 len = strlen(data);
1928                 if (len > maxlen)
1929                         len = maxlen;
1930
1931                 if (*ppos > len) {
1932                         *lenp = 0;
1933                         return 0;
1934                 }
1935
1936                 data += *ppos;
1937                 len  -= *ppos;
1938
1939                 if (len > *lenp)
1940                         len = *lenp;
1941                 if (len)
1942                         if (copy_to_user(buffer, data, len))
1943                                 return -EFAULT;
1944                 if (len < *lenp) {
1945                         if (put_user('\n', buffer + len))
1946                                 return -EFAULT;
1947                         len++;
1948                 }
1949                 *lenp = len;
1950                 *ppos += len;
1951         }
1952         return 0;
1953 }
1954
1955 static void warn_sysctl_write(struct ctl_table *table)
1956 {
1957         pr_warn_once("%s wrote to %s when file position was not 0!\n"
1958                 "This will not be supported in the future. To silence this\n"
1959                 "warning, set kernel.sysctl_writes_strict = -1\n",
1960                 current->comm, table->procname);
1961 }
1962
1963 /**
1964  * proc_first_pos_non_zero_ignore - check if firs position is allowed
1965  * @ppos: file position
1966  * @table: the sysctl table
1967  *
1968  * Returns true if the first position is non-zero and the sysctl_writes_strict
1969  * mode indicates this is not allowed for numeric input types. String proc
1970  * hadlers can ignore the return value.
1971  */
1972 static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
1973                                            struct ctl_table *table)
1974 {
1975         if (!*ppos)
1976                 return false;
1977
1978         switch (sysctl_writes_strict) {
1979         case SYSCTL_WRITES_STRICT:
1980                 return true;
1981         case SYSCTL_WRITES_WARN:
1982                 warn_sysctl_write(table);
1983                 return false;
1984         default:
1985                 return false;
1986         }
1987 }
1988
1989 /**
1990  * proc_dostring - read a string sysctl
1991  * @table: the sysctl table
1992  * @write: %TRUE if this is a write to the sysctl file
1993  * @buffer: the user buffer
1994  * @lenp: the size of the user buffer
1995  * @ppos: file position
1996  *
1997  * Reads/writes a string from/to the user buffer. If the kernel
1998  * buffer provided is not large enough to hold the string, the
1999  * string is truncated. The copied string is %NULL-terminated.
2000  * If the string is being read by the user process, it is copied
2001  * and a newline '\n' is added. It is truncated if the buffer is
2002  * not large enough.
2003  *
2004  * Returns 0 on success.
2005  */
2006 int proc_dostring(struct ctl_table *table, int write,
2007                   void __user *buffer, size_t *lenp, loff_t *ppos)
2008 {
2009         if (write)
2010                 proc_first_pos_non_zero_ignore(ppos, table);
2011
2012         return _proc_do_string((char *)(table->data), table->maxlen, write,
2013                                (char __user *)buffer, lenp, ppos);
2014 }
2015
2016 static size_t proc_skip_spaces(char **buf)
2017 {
2018         size_t ret;
2019         char *tmp = skip_spaces(*buf);
2020         ret = tmp - *buf;
2021         *buf = tmp;
2022         return ret;
2023 }
2024
2025 static void proc_skip_char(char **buf, size_t *size, const char v)
2026 {
2027         while (*size) {
2028                 if (**buf != v)
2029                         break;
2030                 (*size)--;
2031                 (*buf)++;
2032         }
2033 }
2034
2035 #define TMPBUFLEN 22
2036 /**
2037  * proc_get_long - reads an ASCII formatted integer from a user buffer
2038  *
2039  * @buf: a kernel buffer
2040  * @size: size of the kernel buffer
2041  * @val: this is where the number will be stored
2042  * @neg: set to %TRUE if number is negative
2043  * @perm_tr: a vector which contains the allowed trailers
2044  * @perm_tr_len: size of the perm_tr vector
2045  * @tr: pointer to store the trailer character
2046  *
2047  * In case of success %0 is returned and @buf and @size are updated with
2048  * the amount of bytes read. If @tr is non-NULL and a trailing
2049  * character exists (size is non-zero after returning from this
2050  * function), @tr is updated with the trailing character.
2051  */
2052 static int proc_get_long(char **buf, size_t *size,
2053                           unsigned long *val, bool *neg,
2054                           const char *perm_tr, unsigned perm_tr_len, char *tr)
2055 {
2056         int len;
2057         char *p, tmp[TMPBUFLEN];
2058
2059         if (!*size)
2060                 return -EINVAL;
2061
2062         len = *size;
2063         if (len > TMPBUFLEN - 1)
2064                 len = TMPBUFLEN - 1;
2065
2066         memcpy(tmp, *buf, len);
2067
2068         tmp[len] = 0;
2069         p = tmp;
2070         if (*p == '-' && *size > 1) {
2071                 *neg = true;
2072                 p++;
2073         } else
2074                 *neg = false;
2075         if (!isdigit(*p))
2076                 return -EINVAL;
2077
2078         *val = simple_strtoul(p, &p, 0);
2079
2080         len = p - tmp;
2081
2082         /* We don't know if the next char is whitespace thus we may accept
2083          * invalid integers (e.g. 1234...a) or two integers instead of one
2084          * (e.g. 123...1). So lets not allow such large numbers. */
2085         if (len == TMPBUFLEN - 1)
2086                 return -EINVAL;
2087
2088         if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2089                 return -EINVAL;
2090
2091         if (tr && (len < *size))
2092                 *tr = *p;
2093
2094         *buf += len;
2095         *size -= len;
2096
2097         return 0;
2098 }
2099
2100 /**
2101  * proc_put_long - converts an integer to a decimal ASCII formatted string
2102  *
2103  * @buf: the user buffer
2104  * @size: the size of the user buffer
2105  * @val: the integer to be converted
2106  * @neg: sign of the number, %TRUE for negative
2107  *
2108  * In case of success %0 is returned and @buf and @size are updated with
2109  * the amount of bytes written.
2110  */
2111 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2112                           bool neg)
2113 {
2114         int len;
2115         char tmp[TMPBUFLEN], *p = tmp;
2116
2117         sprintf(p, "%s%lu", neg ? "-" : "", val);
2118         len = strlen(tmp);
2119         if (len > *size)
2120                 len = *size;
2121         if (copy_to_user(*buf, tmp, len))
2122                 return -EFAULT;
2123         *size -= len;
2124         *buf += len;
2125         return 0;
2126 }
2127 #undef TMPBUFLEN
2128
2129 static int proc_put_char(void __user **buf, size_t *size, char c)
2130 {
2131         if (*size) {
2132                 char __user **buffer = (char __user **)buf;
2133                 if (put_user(c, *buffer))
2134                         return -EFAULT;
2135                 (*size)--, (*buffer)++;
2136                 *buf = *buffer;
2137         }
2138         return 0;
2139 }
2140
2141 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2142                                  int *valp,
2143                                  int write, void *data)
2144 {
2145         if (write) {
2146                 if (*negp) {
2147                         if (*lvalp > (unsigned long) INT_MAX + 1)
2148                                 return -EINVAL;
2149                         *valp = -*lvalp;
2150                 } else {
2151                         if (*lvalp > (unsigned long) INT_MAX)
2152                                 return -EINVAL;
2153                         *valp = *lvalp;
2154                 }
2155         } else {
2156                 int val = *valp;
2157                 if (val < 0) {
2158                         *negp = true;
2159                         *lvalp = -(unsigned long)val;
2160                 } else {
2161                         *negp = false;
2162                         *lvalp = (unsigned long)val;
2163                 }
2164         }
2165         return 0;
2166 }
2167
2168 static int do_proc_douintvec_conv(unsigned long *lvalp,
2169                                   unsigned int *valp,
2170                                   int write, void *data)
2171 {
2172         if (write) {
2173                 if (*lvalp > UINT_MAX)
2174                         return -EINVAL;
2175                 *valp = *lvalp;
2176         } else {
2177                 unsigned int val = *valp;
2178                 *lvalp = (unsigned long)val;
2179         }
2180         return 0;
2181 }
2182
2183 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2184
2185 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2186                   int write, void __user *buffer,
2187                   size_t *lenp, loff_t *ppos,
2188                   int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2189                               int write, void *data),
2190                   void *data)
2191 {
2192         int *i, vleft, first = 1, err = 0;
2193         size_t left;
2194         char *kbuf = NULL, *p;
2195
2196         if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2197                 *lenp = 0;
2198                 return 0;
2199         }
2200
2201         i = (int *) tbl_data;
2202         vleft = table->maxlen / sizeof(*i);
2203         left = *lenp;
2204
2205         if (!conv)
2206                 conv = do_proc_dointvec_conv;
2207
2208         if (write) {
2209                 if (proc_first_pos_non_zero_ignore(ppos, table))
2210                         goto out;
2211
2212                 if (left > PAGE_SIZE - 1)
2213                         left = PAGE_SIZE - 1;
2214                 p = kbuf = memdup_user_nul(buffer, left);
2215                 if (IS_ERR(kbuf))
2216                         return PTR_ERR(kbuf);
2217         }
2218
2219         for (; left && vleft--; i++, first=0) {
2220                 unsigned long lval;
2221                 bool neg;
2222
2223                 if (write) {
2224                         left -= proc_skip_spaces(&p);
2225
2226                         if (!left)
2227                                 break;
2228                         err = proc_get_long(&p, &left, &lval, &neg,
2229                                              proc_wspace_sep,
2230                                              sizeof(proc_wspace_sep), NULL);
2231                         if (err)
2232                                 break;
2233                         if (conv(&neg, &lval, i, 1, data)) {
2234                                 err = -EINVAL;
2235                                 break;
2236                         }
2237                 } else {
2238                         if (conv(&neg, &lval, i, 0, data)) {
2239                                 err = -EINVAL;
2240                                 break;
2241                         }
2242                         if (!first)
2243                                 err = proc_put_char(&buffer, &left, '\t');
2244                         if (err)
2245                                 break;
2246                         err = proc_put_long(&buffer, &left, lval, neg);
2247                         if (err)
2248                                 break;
2249                 }
2250         }
2251
2252         if (!write && !first && left && !err)
2253                 err = proc_put_char(&buffer, &left, '\n');
2254         if (write && !err && left)
2255                 left -= proc_skip_spaces(&p);
2256         if (write) {
2257                 kfree(kbuf);
2258                 if (first)
2259                         return err ? : -EINVAL;
2260         }
2261         *lenp -= left;
2262 out:
2263         *ppos += *lenp;
2264         return err;
2265 }
2266
2267 static int do_proc_dointvec(struct ctl_table *table, int write,
2268                   void __user *buffer, size_t *lenp, loff_t *ppos,
2269                   int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2270                               int write, void *data),
2271                   void *data)
2272 {
2273         return __do_proc_dointvec(table->data, table, write,
2274                         buffer, lenp, ppos, conv, data);
2275 }
2276
2277 static int do_proc_douintvec_w(unsigned int *tbl_data,
2278                                struct ctl_table *table,
2279                                void __user *buffer,
2280                                size_t *lenp, loff_t *ppos,
2281                                int (*conv)(unsigned long *lvalp,
2282                                            unsigned int *valp,
2283                                            int write, void *data),
2284                                void *data)
2285 {
2286         unsigned long lval;
2287         int err = 0;
2288         size_t left;
2289         bool neg;
2290         char *kbuf = NULL, *p;
2291
2292         left = *lenp;
2293
2294         if (proc_first_pos_non_zero_ignore(ppos, table))
2295                 goto bail_early;
2296
2297         if (left > PAGE_SIZE - 1)
2298                 left = PAGE_SIZE - 1;
2299
2300         p = kbuf = memdup_user_nul(buffer, left);
2301         if (IS_ERR(kbuf))
2302                 return -EINVAL;
2303
2304         left -= proc_skip_spaces(&p);
2305         if (!left) {
2306                 err = -EINVAL;
2307                 goto out_free;
2308         }
2309
2310         err = proc_get_long(&p, &left, &lval, &neg,
2311                              proc_wspace_sep,
2312                              sizeof(proc_wspace_sep), NULL);
2313         if (err || neg) {
2314                 err = -EINVAL;
2315                 goto out_free;
2316         }
2317
2318         if (conv(&lval, tbl_data, 1, data)) {
2319                 err = -EINVAL;
2320                 goto out_free;
2321         }
2322
2323         if (!err && left)
2324                 left -= proc_skip_spaces(&p);
2325
2326 out_free:
2327         kfree(kbuf);
2328         if (err)
2329                 return -EINVAL;
2330
2331         return 0;
2332
2333         /* This is in keeping with old __do_proc_dointvec() */
2334 bail_early:
2335         *ppos += *lenp;
2336         return err;
2337 }
2338
2339 static int do_proc_douintvec_r(unsigned int *tbl_data, void __user *buffer,
2340                                size_t *lenp, loff_t *ppos,
2341                                int (*conv)(unsigned long *lvalp,
2342                                            unsigned int *valp,
2343                                            int write, void *data),
2344                                void *data)
2345 {
2346         unsigned long lval;
2347         int err = 0;
2348         size_t left;
2349
2350         left = *lenp;
2351
2352         if (conv(&lval, tbl_data, 0, data)) {
2353                 err = -EINVAL;
2354                 goto out;
2355         }
2356
2357         err = proc_put_long(&buffer, &left, lval, false);
2358         if (err || !left)
2359                 goto out;
2360
2361         err = proc_put_char(&buffer, &left, '\n');
2362
2363 out:
2364         *lenp -= left;
2365         *ppos += *lenp;
2366
2367         return err;
2368 }
2369
2370 static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
2371                                int write, void __user *buffer,
2372                                size_t *lenp, loff_t *ppos,
2373                                int (*conv)(unsigned long *lvalp,
2374                                            unsigned int *valp,
2375                                            int write, void *data),
2376                                void *data)
2377 {
2378         unsigned int *i, vleft;
2379
2380         if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2381                 *lenp = 0;
2382                 return 0;
2383         }
2384
2385         i = (unsigned int *) tbl_data;
2386         vleft = table->maxlen / sizeof(*i);
2387
2388         /*
2389          * Arrays are not supported, keep this simple. *Do not* add
2390          * support for them.
2391          */
2392         if (vleft != 1) {
2393                 *lenp = 0;
2394                 return -EINVAL;
2395         }
2396
2397         if (!conv)
2398                 conv = do_proc_douintvec_conv;
2399
2400         if (write)
2401                 return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
2402                                            conv, data);
2403         return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
2404 }
2405
2406 static int do_proc_douintvec(struct ctl_table *table, int write,
2407                              void __user *buffer, size_t *lenp, loff_t *ppos,
2408                              int (*conv)(unsigned long *lvalp,
2409                                          unsigned int *valp,
2410                                          int write, void *data),
2411                              void *data)
2412 {
2413         return __do_proc_douintvec(table->data, table, write,
2414                                    buffer, lenp, ppos, conv, data);
2415 }
2416
2417 /**
2418  * proc_dointvec - read a vector of integers
2419  * @table: the sysctl table
2420  * @write: %TRUE if this is a write to the sysctl file
2421  * @buffer: the user buffer
2422  * @lenp: the size of the user buffer
2423  * @ppos: file position
2424  *
2425  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2426  * values from/to the user buffer, treated as an ASCII string.
2427  *
2428  * Returns 0 on success.
2429  */
2430 int proc_dointvec(struct ctl_table *table, int write,
2431                      void __user *buffer, size_t *lenp, loff_t *ppos)
2432 {
2433         return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
2434 }
2435
2436 /**
2437  * proc_douintvec - read a vector of unsigned integers
2438  * @table: the sysctl table
2439  * @write: %TRUE if this is a write to the sysctl file
2440  * @buffer: the user buffer
2441  * @lenp: the size of the user buffer
2442  * @ppos: file position
2443  *
2444  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2445  * values from/to the user buffer, treated as an ASCII string.
2446  *
2447  * Returns 0 on success.
2448  */
2449 int proc_douintvec(struct ctl_table *table, int write,
2450                      void __user *buffer, size_t *lenp, loff_t *ppos)
2451 {
2452         return do_proc_douintvec(table, write, buffer, lenp, ppos,
2453                                  do_proc_douintvec_conv, NULL);
2454 }
2455
2456 /*
2457  * Taint values can only be increased
2458  * This means we can safely use a temporary.
2459  */
2460 static int proc_taint(struct ctl_table *table, int write,
2461                                void __user *buffer, size_t *lenp, loff_t *ppos)
2462 {
2463         struct ctl_table t;
2464         unsigned long tmptaint = get_taint();
2465         int err;
2466
2467         if (write && !capable(CAP_SYS_ADMIN))
2468                 return -EPERM;
2469
2470         t = *table;
2471         t.data = &tmptaint;
2472         err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2473         if (err < 0)
2474                 return err;
2475
2476         if (write) {
2477                 /*
2478                  * Poor man's atomic or. Not worth adding a primitive
2479                  * to everyone's atomic.h for this
2480                  */
2481                 int i;
2482                 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2483                         if ((tmptaint >> i) & 1)
2484                                 add_taint(i, LOCKDEP_STILL_OK);
2485                 }
2486         }
2487
2488         return err;
2489 }
2490
2491 #ifdef CONFIG_PRINTK
2492 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2493                                 void __user *buffer, size_t *lenp, loff_t *ppos)
2494 {
2495         if (write && !capable(CAP_SYS_ADMIN))
2496                 return -EPERM;
2497
2498         return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2499 }
2500 #endif
2501
2502 struct do_proc_dointvec_minmax_conv_param {
2503         int *min;
2504         int *max;
2505 };
2506
2507 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2508                                         int *valp,
2509                                         int write, void *data)
2510 {
2511         struct do_proc_dointvec_minmax_conv_param *param = data;
2512         if (write) {
2513                 int val = *negp ? -*lvalp : *lvalp;
2514                 if ((param->min && *param->min > val) ||
2515                     (param->max && *param->max < val))
2516                         return -EINVAL;
2517                 *valp = val;
2518         } else {
2519                 int val = *valp;
2520                 if (val < 0) {
2521                         *negp = true;
2522                         *lvalp = -(unsigned long)val;
2523                 } else {
2524                         *negp = false;
2525                         *lvalp = (unsigned long)val;
2526                 }
2527         }
2528         return 0;
2529 }
2530
2531 /**
2532  * proc_dointvec_minmax - read a vector of integers with min/max values
2533  * @table: the sysctl table
2534  * @write: %TRUE if this is a write to the sysctl file
2535  * @buffer: the user buffer
2536  * @lenp: the size of the user buffer
2537  * @ppos: file position
2538  *
2539  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2540  * values from/to the user buffer, treated as an ASCII string.
2541  *
2542  * This routine will ensure the values are within the range specified by
2543  * table->extra1 (min) and table->extra2 (max).
2544  *
2545  * Returns 0 on success.
2546  */
2547 int proc_dointvec_minmax(struct ctl_table *table, int write,
2548                   void __user *buffer, size_t *lenp, loff_t *ppos)
2549 {
2550         struct do_proc_dointvec_minmax_conv_param param = {
2551                 .min = (int *) table->extra1,
2552                 .max = (int *) table->extra2,
2553         };
2554         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2555                                 do_proc_dointvec_minmax_conv, &param);
2556 }
2557
2558 struct do_proc_douintvec_minmax_conv_param {
2559         unsigned int *min;
2560         unsigned int *max;
2561 };
2562
2563 static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
2564                                          unsigned int *valp,
2565                                          int write, void *data)
2566 {
2567         struct do_proc_douintvec_minmax_conv_param *param = data;
2568
2569         if (write) {
2570                 unsigned int val = *lvalp;
2571
2572                 if (*lvalp > UINT_MAX)
2573                         return -EINVAL;
2574
2575                 if ((param->min && *param->min > val) ||
2576                     (param->max && *param->max < val))
2577                         return -ERANGE;
2578
2579                 *valp = val;
2580         } else {
2581                 unsigned int val = *valp;
2582                 *lvalp = (unsigned long) val;
2583         }
2584
2585         return 0;
2586 }
2587
2588 /**
2589  * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
2590  * @table: the sysctl table
2591  * @write: %TRUE if this is a write to the sysctl file
2592  * @buffer: the user buffer
2593  * @lenp: the size of the user buffer
2594  * @ppos: file position
2595  *
2596  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2597  * values from/to the user buffer, treated as an ASCII string. Negative
2598  * strings are not allowed.
2599  *
2600  * This routine will ensure the values are within the range specified by
2601  * table->extra1 (min) and table->extra2 (max). There is a final sanity
2602  * check for UINT_MAX to avoid having to support wrap around uses from
2603  * userspace.
2604  *
2605  * Returns 0 on success.
2606  */
2607 int proc_douintvec_minmax(struct ctl_table *table, int write,
2608                           void __user *buffer, size_t *lenp, loff_t *ppos)
2609 {
2610         struct do_proc_douintvec_minmax_conv_param param = {
2611                 .min = (unsigned int *) table->extra1,
2612                 .max = (unsigned int *) table->extra2,
2613         };
2614         return do_proc_douintvec(table, write, buffer, lenp, ppos,
2615                                  do_proc_douintvec_minmax_conv, &param);
2616 }
2617
2618 struct do_proc_dopipe_max_size_conv_param {
2619         unsigned int *min;
2620 };
2621
2622 static int do_proc_dopipe_max_size_conv(unsigned long *lvalp,
2623                                         unsigned int *valp,
2624                                         int write, void *data)
2625 {
2626         struct do_proc_dopipe_max_size_conv_param *param = data;
2627
2628         if (write) {
2629                 unsigned int val;
2630
2631                 if (*lvalp > UINT_MAX)
2632                         return -EINVAL;
2633
2634                 val = round_pipe_size(*lvalp);
2635                 if (val == 0)
2636                         return -EINVAL;
2637
2638                 if (param->min && *param->min > val)
2639                         return -ERANGE;
2640
2641                 *valp = val;
2642         } else {
2643                 unsigned int val = *valp;
2644                 *lvalp = (unsigned long) val;
2645         }
2646
2647         return 0;
2648 }
2649
2650 int proc_dopipe_max_size(struct ctl_table *table, int write,
2651                          void __user *buffer, size_t *lenp, loff_t *ppos)
2652 {
2653         struct do_proc_dopipe_max_size_conv_param param = {
2654                 .min = (unsigned int *) table->extra1,
2655         };
2656         return do_proc_douintvec(table, write, buffer, lenp, ppos,
2657                                  do_proc_dopipe_max_size_conv, &param);
2658 }
2659
2660 static void validate_coredump_safety(void)
2661 {
2662 #ifdef CONFIG_COREDUMP
2663         if (suid_dumpable == SUID_DUMP_ROOT &&
2664             core_pattern[0] != '/' && core_pattern[0] != '|') {
2665                 printk(KERN_WARNING
2666 "Unsafe core_pattern used with fs.suid_dumpable=2.\n"
2667 "Pipe handler or fully qualified core dump path required.\n"
2668 "Set kernel.core_pattern before fs.suid_dumpable.\n"
2669                 );
2670         }
2671 #endif
2672 }
2673
2674 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2675                 void __user *buffer, size_t *lenp, loff_t *ppos)
2676 {
2677         int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2678         if (!error)
2679                 validate_coredump_safety();
2680         return error;
2681 }
2682
2683 #ifdef CONFIG_COREDUMP
2684 static int proc_dostring_coredump(struct ctl_table *table, int write,
2685                   void __user *buffer, size_t *lenp, loff_t *ppos)
2686 {
2687         int error = proc_dostring(table, write, buffer, lenp, ppos);
2688         if (!error)
2689                 validate_coredump_safety();
2690         return error;
2691 }
2692 #endif
2693
2694 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2695                                      void __user *buffer,
2696                                      size_t *lenp, loff_t *ppos,
2697                                      unsigned long convmul,
2698                                      unsigned long convdiv)
2699 {
2700         unsigned long *i, *min, *max;
2701         int vleft, first = 1, err = 0;
2702         size_t left;
2703         char *kbuf = NULL, *p;
2704
2705         if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2706                 *lenp = 0;
2707                 return 0;
2708         }
2709
2710         i = (unsigned long *) data;
2711         min = (unsigned long *) table->extra1;
2712         max = (unsigned long *) table->extra2;
2713         vleft = table->maxlen / sizeof(unsigned long);
2714         left = *lenp;
2715
2716         if (write) {
2717                 if (proc_first_pos_non_zero_ignore(ppos, table))
2718                         goto out;
2719
2720                 if (left > PAGE_SIZE - 1)
2721                         left = PAGE_SIZE - 1;
2722                 p = kbuf = memdup_user_nul(buffer, left);
2723                 if (IS_ERR(kbuf))
2724                         return PTR_ERR(kbuf);
2725         }
2726
2727         for (; left && vleft--; i++, first = 0) {
2728                 unsigned long val;
2729
2730                 if (write) {
2731                         bool neg;
2732
2733                         left -= proc_skip_spaces(&p);
2734
2735                         err = proc_get_long(&p, &left, &val, &neg,
2736                                              proc_wspace_sep,
2737                                              sizeof(proc_wspace_sep), NULL);
2738                         if (err)
2739                                 break;
2740                         if (neg)
2741                                 continue;
2742                         val = convmul * val / convdiv;
2743                         if ((min && val < *min) || (max && val > *max))
2744                                 continue;
2745                         *i = val;
2746                 } else {
2747                         val = convdiv * (*i) / convmul;
2748                         if (!first) {
2749                                 err = proc_put_char(&buffer, &left, '\t');
2750                                 if (err)
2751                                         break;
2752                         }
2753                         err = proc_put_long(&buffer, &left, val, false);
2754                         if (err)
2755                                 break;
2756                 }
2757         }
2758
2759         if (!write && !first && left && !err)
2760                 err = proc_put_char(&buffer, &left, '\n');
2761         if (write && !err)
2762                 left -= proc_skip_spaces(&p);
2763         if (write) {
2764                 kfree(kbuf);
2765                 if (first)
2766                         return err ? : -EINVAL;
2767         }
2768         *lenp -= left;
2769 out:
2770         *ppos += *lenp;
2771         return err;
2772 }
2773
2774 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2775                                      void __user *buffer,
2776                                      size_t *lenp, loff_t *ppos,
2777                                      unsigned long convmul,
2778                                      unsigned long convdiv)
2779 {
2780         return __do_proc_doulongvec_minmax(table->data, table, write,
2781                         buffer, lenp, ppos, convmul, convdiv);
2782 }
2783
2784 /**
2785  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2786  * @table: the sysctl table
2787  * @write: %TRUE if this is a write to the sysctl file
2788  * @buffer: the user buffer
2789  * @lenp: the size of the user buffer
2790  * @ppos: file position
2791  *
2792  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2793  * values from/to the user buffer, treated as an ASCII string.
2794  *
2795  * This routine will ensure the values are within the range specified by
2796  * table->extra1 (min) and table->extra2 (max).
2797  *
2798  * Returns 0 on success.
2799  */
2800 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2801                            void __user *buffer, size_t *lenp, loff_t *ppos)
2802 {
2803     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2804 }
2805
2806 /**
2807  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2808  * @table: the sysctl table
2809  * @write: %TRUE if this is a write to the sysctl file
2810  * @buffer: the user buffer
2811  * @lenp: the size of the user buffer
2812  * @ppos: file position
2813  *
2814  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2815  * values from/to the user buffer, treated as an ASCII string. The values
2816  * are treated as milliseconds, and converted to jiffies when they are stored.
2817  *
2818  * This routine will ensure the values are within the range specified by
2819  * table->extra1 (min) and table->extra2 (max).
2820  *
2821  * Returns 0 on success.
2822  */
2823 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2824                                       void __user *buffer,
2825                                       size_t *lenp, loff_t *ppos)
2826 {
2827     return do_proc_doulongvec_minmax(table, write, buffer,
2828                                      lenp, ppos, HZ, 1000l);
2829 }
2830
2831
2832 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2833                                          int *valp,
2834                                          int write, void *data)
2835 {
2836         if (write) {
2837                 if (*lvalp > INT_MAX / HZ)
2838                         return 1;
2839                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2840         } else {
2841                 int val = *valp;
2842                 unsigned long lval;
2843                 if (val < 0) {
2844                         *negp = true;
2845                         lval = -(unsigned long)val;
2846                 } else {
2847                         *negp = false;
2848                         lval = (unsigned long)val;
2849                 }
2850                 *lvalp = lval / HZ;
2851         }
2852         return 0;
2853 }
2854
2855 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2856                                                 int *valp,
2857                                                 int write, void *data)
2858 {
2859         if (write) {
2860                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2861                         return 1;
2862                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2863         } else {
2864                 int val = *valp;
2865                 unsigned long lval;
2866                 if (val < 0) {
2867                         *negp = true;
2868                         lval = -(unsigned long)val;
2869                 } else {
2870                         *negp = false;
2871                         lval = (unsigned long)val;
2872                 }
2873                 *lvalp = jiffies_to_clock_t(lval);
2874         }
2875         return 0;
2876 }
2877
2878 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2879                                             int *valp,
2880                                             int write, void *data)
2881 {
2882         if (write) {
2883                 unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2884
2885                 if (jif > INT_MAX)
2886                         return 1;
2887                 *valp = (int)jif;
2888         } else {
2889                 int val = *valp;
2890                 unsigned long lval;
2891                 if (val < 0) {
2892                         *negp = true;
2893                         lval = -(unsigned long)val;
2894                 } else {
2895                         *negp = false;
2896                         lval = (unsigned long)val;
2897                 }
2898                 *lvalp = jiffies_to_msecs(lval);
2899         }
2900         return 0;
2901 }
2902
2903 /**
2904  * proc_dointvec_jiffies - read a vector of integers as seconds
2905  * @table: the sysctl table
2906  * @write: %TRUE if this is a write to the sysctl file
2907  * @buffer: the user buffer
2908  * @lenp: the size of the user buffer
2909  * @ppos: file position
2910  *
2911  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2912  * values from/to the user buffer, treated as an ASCII string.
2913  * The values read are assumed to be in seconds, and are converted into
2914  * jiffies.
2915  *
2916  * Returns 0 on success.
2917  */
2918 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2919                           void __user *buffer, size_t *lenp, loff_t *ppos)
2920 {
2921     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2922                             do_proc_dointvec_jiffies_conv,NULL);
2923 }
2924
2925 /**
2926  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2927  * @table: the sysctl table
2928  * @write: %TRUE if this is a write to the sysctl file
2929  * @buffer: the user buffer
2930  * @lenp: the size of the user buffer
2931  * @ppos: pointer to the file position
2932  *
2933  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2934  * values from/to the user buffer, treated as an ASCII string.
2935  * The values read are assumed to be in 1/USER_HZ seconds, and
2936  * are converted into jiffies.
2937  *
2938  * Returns 0 on success.
2939  */
2940 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2941                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2942 {
2943     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2944                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2945 }
2946
2947 /**
2948  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2949  * @table: the sysctl table
2950  * @write: %TRUE if this is a write to the sysctl file
2951  * @buffer: the user buffer
2952  * @lenp: the size of the user buffer
2953  * @ppos: file position
2954  * @ppos: the current position in the file
2955  *
2956  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2957  * values from/to the user buffer, treated as an ASCII string.
2958  * The values read are assumed to be in 1/1000 seconds, and
2959  * are converted into jiffies.
2960  *
2961  * Returns 0 on success.
2962  */
2963 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2964                              void __user *buffer, size_t *lenp, loff_t *ppos)
2965 {
2966         return do_proc_dointvec(table, write, buffer, lenp, ppos,
2967                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2968 }
2969
2970 static int proc_do_cad_pid(struct ctl_table *table, int write,
2971                            void __user *buffer, size_t *lenp, loff_t *ppos)
2972 {
2973         struct pid *new_pid;
2974         pid_t tmp;
2975         int r;
2976
2977         tmp = pid_vnr(cad_pid);
2978
2979         r = __do_proc_dointvec(&tmp, table, write, buffer,
2980                                lenp, ppos, NULL, NULL);
2981         if (r || !write)
2982                 return r;
2983
2984         new_pid = find_get_pid(tmp);
2985         if (!new_pid)
2986                 return -ESRCH;
2987
2988         put_pid(xchg(&cad_pid, new_pid));
2989         return 0;
2990 }
2991
2992 /**
2993  * proc_do_large_bitmap - read/write from/to a large bitmap
2994  * @table: the sysctl table
2995  * @write: %TRUE if this is a write to the sysctl file
2996  * @buffer: the user buffer
2997  * @lenp: the size of the user buffer
2998  * @ppos: file position
2999  *
3000  * The bitmap is stored at table->data and the bitmap length (in bits)
3001  * in table->maxlen.
3002  *
3003  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
3004  * large bitmaps may be represented in a compact manner. Writing into
3005  * the file will clear the bitmap then update it with the given input.
3006  *
3007  * Returns 0 on success.
3008  */
3009 int proc_do_large_bitmap(struct ctl_table *table, int write,
3010                          void __user *buffer, size_t *lenp, loff_t *ppos)
3011 {
3012         int err = 0;
3013         bool first = 1;
3014         size_t left = *lenp;
3015         unsigned long bitmap_len = table->maxlen;
3016         unsigned long *bitmap = *(unsigned long **) table->data;
3017         unsigned long *tmp_bitmap = NULL;
3018         char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
3019
3020         if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
3021                 *lenp = 0;
3022                 return 0;
3023         }
3024
3025         if (write) {
3026                 char *kbuf, *p;
3027
3028                 if (left > PAGE_SIZE - 1)
3029                         left = PAGE_SIZE - 1;
3030
3031                 p = kbuf = memdup_user_nul(buffer, left);
3032                 if (IS_ERR(kbuf))
3033                         return PTR_ERR(kbuf);
3034
3035                 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
3036                                      GFP_KERNEL);
3037                 if (!tmp_bitmap) {
3038                         kfree(kbuf);
3039                         return -ENOMEM;
3040                 }
3041                 proc_skip_char(&p, &left, '\n');
3042                 while (!err && left) {
3043                         unsigned long val_a, val_b;
3044                         bool neg;
3045
3046                         err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
3047                                              sizeof(tr_a), &c);
3048                         if (err)
3049                                 break;
3050                         if (val_a >= bitmap_len || neg) {
3051                                 err = -EINVAL;
3052                                 break;
3053                         }
3054
3055                         val_b = val_a;
3056                         if (left) {
3057                                 p++;
3058                                 left--;
3059                         }
3060
3061                         if (c == '-') {
3062                                 err = proc_get_long(&p, &left, &val_b,
3063                                                      &neg, tr_b, sizeof(tr_b),
3064                                                      &c);
3065                                 if (err)
3066                                         break;
3067                                 if (val_b >= bitmap_len || neg ||
3068                                     val_a > val_b) {
3069                                         err = -EINVAL;
3070                                         break;
3071                                 }
3072                                 if (left) {
3073                                         p++;
3074                                         left--;
3075                                 }
3076                         }
3077
3078                         bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
3079                         first = 0;
3080                         proc_skip_char(&p, &left, '\n');
3081                 }
3082                 kfree(kbuf);
3083         } else {
3084                 unsigned long bit_a, bit_b = 0;
3085
3086                 while (left) {
3087                         bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
3088                         if (bit_a >= bitmap_len)
3089                                 break;
3090                         bit_b = find_next_zero_bit(bitmap, bitmap_len,
3091                                                    bit_a + 1) - 1;
3092
3093                         if (!first) {
3094                                 err = proc_put_char(&buffer, &left, ',');
3095                                 if (err)
3096                                         break;
3097                         }
3098                         err = proc_put_long(&buffer, &left, bit_a, false);
3099                         if (err)
3100                                 break;
3101                         if (bit_a != bit_b) {
3102                                 err = proc_put_char(&buffer, &left, '-');
3103                                 if (err)
3104                                         break;
3105                                 err = proc_put_long(&buffer, &left, bit_b, false);
3106                                 if (err)
3107                                         break;
3108                         }
3109
3110                         first = 0; bit_b++;
3111                 }
3112                 if (!err)
3113                         err = proc_put_char(&buffer, &left, '\n');
3114         }
3115
3116         if (!err) {
3117                 if (write) {
3118                         if (*ppos)
3119                                 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
3120                         else
3121                                 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
3122                 }
3123                 *lenp -= left;
3124                 *ppos += *lenp;
3125         }
3126
3127         kfree(tmp_bitmap);
3128         return err;
3129 }
3130
3131 #else /* CONFIG_PROC_SYSCTL */
3132
3133 int proc_dostring(struct ctl_table *table, int write,
3134                   void __user *buffer, size_t *lenp, loff_t *ppos)
3135 {
3136         return -ENOSYS;
3137 }
3138
3139 int proc_dointvec(struct ctl_table *table, int write,
3140                   void __user *buffer, size_t *lenp, loff_t *ppos)
3141 {
3142         return -ENOSYS;
3143 }
3144
3145 int proc_douintvec(struct ctl_table *table, int write,
3146                   void __user *buffer, size_t *lenp, loff_t *ppos)
3147 {
3148         return -ENOSYS;
3149 }
3150
3151 int proc_dointvec_minmax(struct ctl_table *table, int write,
3152                     void __user *buffer, size_t *lenp, loff_t *ppos)
3153 {
3154         return -ENOSYS;
3155 }
3156
3157 int proc_douintvec_minmax(struct ctl_table *table, int write,
3158                           void __user *buffer, size_t *lenp, loff_t *ppos)
3159 {
3160         return -ENOSYS;
3161 }
3162
3163 int proc_dopipe_max_size(struct ctl_table *table, int write,
3164                          void __user *buffer, size_t *lenp, loff_t *ppos)
3165 {
3166         return -ENOSYS;
3167 }
3168
3169 int proc_dointvec_jiffies(struct ctl_table *table, int write,
3170                     void __user *buffer, size_t *lenp, loff_t *ppos)
3171 {
3172         return -ENOSYS;
3173 }
3174
3175 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
3176                     void __user *buffer, size_t *lenp, loff_t *ppos)
3177 {
3178         return -ENOSYS;
3179 }
3180
3181 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
3182                              void __user *buffer, size_t *lenp, loff_t *ppos)
3183 {
3184         return -ENOSYS;
3185 }
3186
3187 int proc_doulongvec_minmax(struct ctl_table *table, int write,
3188                     void __user *buffer, size_t *lenp, loff_t *ppos)
3189 {
3190         return -ENOSYS;
3191 }
3192
3193 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
3194                                       void __user *buffer,
3195                                       size_t *lenp, loff_t *ppos)
3196 {
3197     return -ENOSYS;
3198 }
3199
3200
3201 #endif /* CONFIG_PROC_SYSCTL */
3202
3203 /*
3204  * No sense putting this after each symbol definition, twice,
3205  * exception granted :-)
3206  */
3207 EXPORT_SYMBOL(proc_dointvec);
3208 EXPORT_SYMBOL(proc_douintvec);
3209 EXPORT_SYMBOL(proc_dointvec_jiffies);
3210 EXPORT_SYMBOL(proc_dointvec_minmax);
3211 EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
3212 EXPORT_SYMBOL_GPL(proc_dopipe_max_size);
3213 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3214 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3215 EXPORT_SYMBOL(proc_dostring);
3216 EXPORT_SYMBOL(proc_doulongvec_minmax);
3217 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);