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   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/mm.h>
  23 #include <linux/swap.h>
  24 #include <linux/slab.h>
  25 #include <linux/sysctl.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/capability.h>
  28 #include <linux/ctype.h>
  29 #include <linux/utsname.h>
  30 #include <linux/capability.h>
  31 #include <linux/smp_lock.h>
  32 #include <linux/init.h>
  33 #include <linux/kernel.h>
  34 #include <linux/kobject.h>
  35 #include <linux/net.h>
  36 #include <linux/sysrq.h>
  37 #include <linux/highuid.h>
  38 #include <linux/writeback.h>
  39 #include <linux/hugetlb.h>
  40 #include <linux/security.h>
  41 #include <linux/initrd.h>
  42 #include <linux/times.h>
  43 #include <linux/limits.h>
  44 #include <linux/dcache.h>
  45 #include <linux/syscalls.h>
  46 #include <linux/nfs_fs.h>
  47 #include <linux/acpi.h>
  48
  49 #include <asm/uaccess.h>
  50 #include <asm/processor.h>
  51
  52 extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
  53                      void __user *buffer, size_t *lenp, loff_t *ppos);
  54
  55 #ifdef CONFIG_X86
  56 #include <asm/nmi.h>
  57 #endif
  58
  59 #if defined(CONFIG_SYSCTL)
  60
  61 /* External variables not in a header file. */
  62 extern int C_A_D;
  63 extern int sysctl_overcommit_memory;
  64 extern int sysctl_overcommit_ratio;
  65 extern int sysctl_panic_on_oom;
  66 extern int max_threads;
  67 extern int sysrq_enabled;
  68 extern int core_uses_pid;
  69 extern int suid_dumpable;
  70 extern char core_pattern[];
  71 extern int cad_pid;
  72 extern int pid_max;
  73 extern int min_free_kbytes;
  74 extern int printk_ratelimit_jiffies;
  75 extern int printk_ratelimit_burst;
  76 extern int pid_max_min, pid_max_max;
  77 extern int sysctl_drop_caches;
  78 extern int percpu_pagelist_fraction;
  79 extern int compat_log;
  80
  81 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  82 static int maxolduid = 65535;
  83 static int minolduid;
  84 static int min_percpu_pagelist_fract = 8;
  85
  86 static int ngroups_max = NGROUPS_MAX;
  87
  88 #ifdef CONFIG_KMOD
  89 extern char modprobe_path[];
  90 #endif
  91 #ifdef CONFIG_CHR_DEV_SG
  92 extern int sg_big_buff;
  93 #endif
  94 #ifdef CONFIG_SYSVIPC
  95 extern size_t shm_ctlmax;
  96 extern size_t shm_ctlall;
  97 extern int shm_ctlmni;
  98 extern int msg_ctlmax;
  99 extern int msg_ctlmnb;
 100 extern int msg_ctlmni;
 101 extern int sem_ctls[];
 102 #endif
 103
 104 #ifdef __sparc__
 105 extern char reboot_command [];
 106 extern int stop_a_enabled;
 107 extern int scons_pwroff;
 108 #endif
 109
 110 #ifdef __hppa__
 111 extern int pwrsw_enabled;
 112 extern int unaligned_enabled;
 113 #endif
 114
 115 #ifdef CONFIG_S390
 116 #ifdef CONFIG_MATHEMU
 117 extern int sysctl_ieee_emulation_warnings;
 118 #endif
 119 extern int sysctl_userprocess_debug;
 120 extern int spin_retry;
 121 #endif
 122
 123 extern int sysctl_hz_timer;
 124
 125 #ifdef CONFIG_BSD_PROCESS_ACCT
 126 extern int acct_parm[];
 127 #endif
 128
 129 #ifdef CONFIG_IA64
 130 extern int no_unaligned_warning;
 131 #endif
 132
 133 #ifdef CONFIG_RT_MUTEXES
 134 extern int max_lock_depth;
 135 #endif
 136
 137 #ifdef CONFIG_SYSCTL_SYSCALL
 138 static int parse_table(int __user *, int, void __user *, size_t __user *,
 139                 void __user *, size_t, ctl_table *, void **);
 140 #endif
 141
 142 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
 143                   void __user *buffer, size_t *lenp, loff_t *ppos);
 144
 145 static ctl_table root_table[];
 146 static struct ctl_table_header root_table_header =
 147         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 148
 149 static ctl_table kern_table[];
 150 static ctl_table vm_table[];
 151 static ctl_table fs_table[];
 152 static ctl_table debug_table[];
 153 static ctl_table dev_table[];
 154 extern ctl_table random_table[];
 155 #ifdef CONFIG_UNIX98_PTYS
 156 extern ctl_table pty_table[];
 157 #endif
 158 #ifdef CONFIG_INOTIFY_USER
 159 extern ctl_table inotify_table[];
 160 #endif
 161
 162 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 163 int sysctl_legacy_va_layout;
 164 #endif
 165
 166 /* /proc declarations: */
 167
 168 #ifdef CONFIG_PROC_SYSCTL
 169
 170 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 171 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 172 static int proc_opensys(struct inode *, struct file *);
 173
 174 struct file_operations proc_sys_file_operations = {
 175         .open           = proc_opensys,
 176         .read           = proc_readsys,
 177         .write          = proc_writesys,
 178 };
 179
 180 extern struct proc_dir_entry *proc_sys_root;
 181
 182 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
 183 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 184 #endif
 185
 186 /* The default sysctl tables: */
 187
 188 static ctl_table root_table[] = {
 189         {
 190                 .ctl_name       = CTL_KERN,
 191                 .procname       = "kernel",
 192                 .mode           = 0555,
 193                 .child          = kern_table,
 194         },
 195         {
 196                 .ctl_name       = CTL_VM,
 197                 .procname       = "vm",
 198                 .mode           = 0555,
 199                 .child          = vm_table,
 200         },
 201 #ifdef CONFIG_NET
 202         {
 203                 .ctl_name       = CTL_NET,
 204                 .procname       = "net",
 205                 .mode           = 0555,
 206                 .child          = net_table,
 207         },
 208 #endif
 209         {
 210                 .ctl_name       = CTL_FS,
 211                 .procname       = "fs",
 212                 .mode           = 0555,
 213                 .child          = fs_table,
 214         },
 215         {
 216                 .ctl_name       = CTL_DEBUG,
 217                 .procname       = "debug",
 218                 .mode           = 0555,
 219                 .child          = debug_table,
 220         },
 221         {
 222                 .ctl_name       = CTL_DEV,
 223                 .procname       = "dev",
 224                 .mode           = 0555,
 225                 .child          = dev_table,
 226         },
 227
 228         { .ctl_name = 0 }
 229 };
 230
 231 static ctl_table kern_table[] = {
 232         {
 233                 .ctl_name       = KERN_OSTYPE,
 234                 .procname       = "ostype",
 235                 .data           = system_utsname.sysname,
 236                 .maxlen         = sizeof(system_utsname.sysname),
 237                 .mode           = 0444,
 238                 .proc_handler   = &proc_doutsstring,
 239                 .strategy       = &sysctl_string,
 240         },
 241         {
 242                 .ctl_name       = KERN_OSRELEASE,
 243                 .procname       = "osrelease",
 244                 .data           = system_utsname.release,
 245                 .maxlen         = sizeof(system_utsname.release),
 246                 .mode           = 0444,
 247                 .proc_handler   = &proc_doutsstring,
 248                 .strategy       = &sysctl_string,
 249         },
 250         {
 251                 .ctl_name       = KERN_VERSION,
 252                 .procname       = "version",
 253                 .data           = system_utsname.version,
 254                 .maxlen         = sizeof(system_utsname.version),
 255                 .mode           = 0444,
 256                 .proc_handler   = &proc_doutsstring,
 257                 .strategy       = &sysctl_string,
 258         },
 259         {
 260                 .ctl_name       = KERN_NODENAME,
 261                 .procname       = "hostname",
 262                 .data           = system_utsname.nodename,
 263                 .maxlen         = sizeof(system_utsname.nodename),
 264                 .mode           = 0644,
 265                 .proc_handler   = &proc_doutsstring,
 266                 .strategy       = &sysctl_string,
 267         },
 268         {
 269                 .ctl_name       = KERN_DOMAINNAME,
 270                 .procname       = "domainname",
 271                 .data           = system_utsname.domainname,
 272                 .maxlen         = sizeof(system_utsname.domainname),
 273                 .mode           = 0644,
 274                 .proc_handler   = &proc_doutsstring,
 275                 .strategy       = &sysctl_string,
 276         },
 277         {
 278                 .ctl_name       = KERN_PANIC,
 279                 .procname       = "panic",
 280                 .data           = &panic_timeout,
 281                 .maxlen         = sizeof(int),
 282                 .mode           = 0644,
 283                 .proc_handler   = &proc_dointvec,
 284         },
 285         {
 286                 .ctl_name       = KERN_CORE_USES_PID,
 287                 .procname       = "core_uses_pid",
 288                 .data           = &core_uses_pid,
 289                 .maxlen         = sizeof(int),
 290                 .mode           = 0644,
 291                 .proc_handler   = &proc_dointvec,
 292         },
 293         {
 294                 .ctl_name       = KERN_CORE_PATTERN,
 295                 .procname       = "core_pattern",
 296                 .data           = core_pattern,
 297                 .maxlen         = 128,
 298                 .mode           = 0644,
 299                 .proc_handler   = &proc_dostring,
 300                 .strategy       = &sysctl_string,
 301         },
 302         {
 303                 .ctl_name       = KERN_TAINTED,
 304                 .procname       = "tainted",
 305                 .data           = &tainted,
 306                 .maxlen         = sizeof(int),
 307                 .mode           = 0444,
 308                 .proc_handler   = &proc_dointvec,
 309         },
 310         {
 311                 .ctl_name       = KERN_CAP_BSET,
 312                 .procname       = "cap-bound",
 313                 .data           = &cap_bset,
 314                 .maxlen         = sizeof(kernel_cap_t),
 315                 .mode           = 0600,
 316                 .proc_handler   = &proc_dointvec_bset,
 317         },
 318 #ifdef CONFIG_BLK_DEV_INITRD
 319         {
 320                 .ctl_name       = KERN_REALROOTDEV,
 321                 .procname       = "real-root-dev",
 322                 .data           = &real_root_dev,
 323                 .maxlen         = sizeof(int),
 324                 .mode           = 0644,
 325                 .proc_handler   = &proc_dointvec,
 326         },
 327 #endif
 328 #ifdef __sparc__
 329         {
 330                 .ctl_name       = KERN_SPARC_REBOOT,
 331                 .procname       = "reboot-cmd",
 332                 .data           = reboot_command,
 333                 .maxlen         = 256,
 334                 .mode           = 0644,
 335                 .proc_handler   = &proc_dostring,
 336                 .strategy       = &sysctl_string,
 337         },
 338         {
 339                 .ctl_name       = KERN_SPARC_STOP_A,
 340                 .procname       = "stop-a",
 341                 .data           = &stop_a_enabled,
 342                 .maxlen         = sizeof (int),
 343                 .mode           = 0644,
 344                 .proc_handler   = &proc_dointvec,
 345         },
 346         {
 347                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 348                 .procname       = "scons-poweroff",
 349                 .data           = &scons_pwroff,
 350                 .maxlen         = sizeof (int),
 351                 .mode           = 0644,
 352                 .proc_handler   = &proc_dointvec,
 353         },
 354 #endif
 355 #ifdef __hppa__
 356         {
 357                 .ctl_name       = KERN_HPPA_PWRSW,
 358                 .procname       = "soft-power",
 359                 .data           = &pwrsw_enabled,
 360                 .maxlen         = sizeof (int),
 361                 .mode           = 0644,
 362                 .proc_handler   = &proc_dointvec,
 363         },
 364         {
 365                 .ctl_name       = KERN_HPPA_UNALIGNED,
 366                 .procname       = "unaligned-trap",
 367                 .data           = &unaligned_enabled,
 368                 .maxlen         = sizeof (int),
 369                 .mode           = 0644,
 370                 .proc_handler   = &proc_dointvec,
 371         },
 372 #endif
 373         {
 374                 .ctl_name       = KERN_CTLALTDEL,
 375                 .procname       = "ctrl-alt-del",
 376                 .data           = &C_A_D,
 377                 .maxlen         = sizeof(int),
 378                 .mode           = 0644,
 379                 .proc_handler   = &proc_dointvec,
 380         },
 381         {
 382                 .ctl_name       = KERN_PRINTK,
 383                 .procname       = "printk",
 384                 .data           = &console_loglevel,
 385                 .maxlen         = 4*sizeof(int),
 386                 .mode           = 0644,
 387                 .proc_handler   = &proc_dointvec,
 388         },
 389 #ifdef CONFIG_KMOD
 390         {
 391                 .ctl_name       = KERN_MODPROBE,
 392                 .procname       = "modprobe",
 393                 .data           = &modprobe_path,
 394                 .maxlen         = KMOD_PATH_LEN,
 395                 .mode           = 0644,
 396                 .proc_handler   = &proc_dostring,
 397                 .strategy       = &sysctl_string,
 398         },
 399 #endif
 400 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 401         {
 402                 .ctl_name       = KERN_HOTPLUG,
 403                 .procname       = "hotplug",
 404                 .data           = &uevent_helper,
 405                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 406                 .mode           = 0644,
 407                 .proc_handler   = &proc_dostring,
 408                 .strategy       = &sysctl_string,
 409         },
 410 #endif
 411 #ifdef CONFIG_CHR_DEV_SG
 412         {
 413                 .ctl_name       = KERN_SG_BIG_BUFF,
 414                 .procname       = "sg-big-buff",
 415                 .data           = &sg_big_buff,
 416                 .maxlen         = sizeof (int),
 417                 .mode           = 0444,
 418                 .proc_handler   = &proc_dointvec,
 419         },
 420 #endif
 421 #ifdef CONFIG_BSD_PROCESS_ACCT
 422         {
 423                 .ctl_name       = KERN_ACCT,
 424                 .procname       = "acct",
 425                 .data           = &acct_parm,
 426                 .maxlen         = 3*sizeof(int),
 427                 .mode           = 0644,
 428                 .proc_handler   = &proc_dointvec,
 429         },
 430 #endif
 431 #ifdef CONFIG_SYSVIPC
 432         {
 433                 .ctl_name       = KERN_SHMMAX,
 434                 .procname       = "shmmax",
 435                 .data           = &shm_ctlmax,
 436                 .maxlen         = sizeof (size_t),
 437                 .mode           = 0644,
 438                 .proc_handler   = &proc_doulongvec_minmax,
 439         },
 440         {
 441                 .ctl_name       = KERN_SHMALL,
 442                 .procname       = "shmall",
 443                 .data           = &shm_ctlall,
 444                 .maxlen         = sizeof (size_t),
 445                 .mode           = 0644,
 446                 .proc_handler   = &proc_doulongvec_minmax,
 447         },
 448         {
 449                 .ctl_name       = KERN_SHMMNI,
 450                 .procname       = "shmmni",
 451                 .data           = &shm_ctlmni,
 452                 .maxlen         = sizeof (int),
 453                 .mode           = 0644,
 454                 .proc_handler   = &proc_dointvec,
 455         },
 456         {
 457                 .ctl_name       = KERN_MSGMAX,
 458                 .procname       = "msgmax",
 459                 .data           = &msg_ctlmax,
 460                 .maxlen         = sizeof (int),
 461                 .mode           = 0644,
 462                 .proc_handler   = &proc_dointvec,
 463         },
 464         {
 465                 .ctl_name       = KERN_MSGMNI,
 466                 .procname       = "msgmni",
 467                 .data           = &msg_ctlmni,
 468                 .maxlen         = sizeof (int),
 469                 .mode           = 0644,
 470                 .proc_handler   = &proc_dointvec,
 471         },
 472         {
 473                 .ctl_name       = KERN_MSGMNB,
 474                 .procname       =  "msgmnb",
 475                 .data           = &msg_ctlmnb,
 476                 .maxlen         = sizeof (int),
 477                 .mode           = 0644,
 478                 .proc_handler   = &proc_dointvec,
 479         },
 480         {
 481                 .ctl_name       = KERN_SEM,
 482                 .procname       = "sem",
 483                 .data           = &sem_ctls,
 484                 .maxlen         = 4*sizeof (int),
 485                 .mode           = 0644,
 486                 .proc_handler   = &proc_dointvec,
 487         },
 488 #endif
 489 #ifdef CONFIG_MAGIC_SYSRQ
 490         {
 491                 .ctl_name       = KERN_SYSRQ,
 492                 .procname       = "sysrq",
 493                 .data           = &sysrq_enabled,
 494                 .maxlen         = sizeof (int),
 495                 .mode           = 0644,
 496                 .proc_handler   = &proc_dointvec,
 497         },
 498 #endif
 499         {
 500                 .ctl_name       = KERN_CADPID,
 501                 .procname       = "cad_pid",
 502                 .data           = &cad_pid,
 503                 .maxlen         = sizeof (int),
 504                 .mode           = 0600,
 505                 .proc_handler   = &proc_dointvec,
 506         },
 507         {
 508                 .ctl_name       = KERN_MAX_THREADS,
 509                 .procname       = "threads-max",
 510                 .data           = &max_threads,
 511                 .maxlen         = sizeof(int),
 512                 .mode           = 0644,
 513                 .proc_handler   = &proc_dointvec,
 514         },
 515         {
 516                 .ctl_name       = KERN_RANDOM,
 517                 .procname       = "random",
 518                 .mode           = 0555,
 519                 .child          = random_table,
 520         },
 521 #ifdef CONFIG_UNIX98_PTYS
 522         {
 523                 .ctl_name       = KERN_PTY,
 524                 .procname       = "pty",
 525                 .mode           = 0555,
 526                 .child          = pty_table,
 527         },
 528 #endif
 529         {
 530                 .ctl_name       = KERN_OVERFLOWUID,
 531                 .procname       = "overflowuid",
 532                 .data           = &overflowuid,
 533                 .maxlen         = sizeof(int),
 534                 .mode           = 0644,
 535                 .proc_handler   = &proc_dointvec_minmax,
 536                 .strategy       = &sysctl_intvec,
 537                 .extra1         = &minolduid,
 538                 .extra2         = &maxolduid,
 539         },
 540         {
 541                 .ctl_name       = KERN_OVERFLOWGID,
 542                 .procname       = "overflowgid",
 543                 .data           = &overflowgid,
 544                 .maxlen         = sizeof(int),
 545                 .mode           = 0644,
 546                 .proc_handler   = &proc_dointvec_minmax,
 547                 .strategy       = &sysctl_intvec,
 548                 .extra1         = &minolduid,
 549                 .extra2         = &maxolduid,
 550         },
 551 #ifdef CONFIG_S390
 552 #ifdef CONFIG_MATHEMU
 553         {
 554                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 555                 .procname       = "ieee_emulation_warnings",
 556                 .data           = &sysctl_ieee_emulation_warnings,
 557                 .maxlen         = sizeof(int),
 558                 .mode           = 0644,
 559                 .proc_handler   = &proc_dointvec,
 560         },
 561 #endif
 562 #ifdef CONFIG_NO_IDLE_HZ
 563         {
 564                 .ctl_name       = KERN_HZ_TIMER,
 565                 .procname       = "hz_timer",
 566                 .data           = &sysctl_hz_timer,
 567                 .maxlen         = sizeof(int),
 568                 .mode           = 0644,
 569                 .proc_handler   = &proc_dointvec,
 570         },
 571 #endif
 572         {
 573                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 574                 .procname       = "userprocess_debug",
 575                 .data           = &sysctl_userprocess_debug,
 576                 .maxlen         = sizeof(int),
 577                 .mode           = 0644,
 578                 .proc_handler   = &proc_dointvec,
 579         },
 580 #endif
 581         {
 582                 .ctl_name       = KERN_PIDMAX,
 583                 .procname       = "pid_max",
 584                 .data           = &pid_max,
 585                 .maxlen         = sizeof (int),
 586                 .mode           = 0644,
 587                 .proc_handler   = &proc_dointvec_minmax,
 588                 .strategy       = sysctl_intvec,
 589                 .extra1         = &pid_max_min,
 590                 .extra2         = &pid_max_max,
 591         },
 592         {
 593                 .ctl_name       = KERN_PANIC_ON_OOPS,
 594                 .procname       = "panic_on_oops",
 595                 .data           = &panic_on_oops,
 596                 .maxlen         = sizeof(int),
 597                 .mode           = 0644,
 598                 .proc_handler   = &proc_dointvec,
 599         },
 600         {
 601                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 602                 .procname       = "printk_ratelimit",
 603                 .data           = &printk_ratelimit_jiffies,
 604                 .maxlen         = sizeof(int),
 605                 .mode           = 0644,
 606                 .proc_handler   = &proc_dointvec_jiffies,
 607                 .strategy       = &sysctl_jiffies,
 608         },
 609         {
 610                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 611                 .procname       = "printk_ratelimit_burst",
 612                 .data           = &printk_ratelimit_burst,
 613                 .maxlen         = sizeof(int),
 614                 .mode           = 0644,
 615                 .proc_handler   = &proc_dointvec,
 616         },
 617         {
 618                 .ctl_name       = KERN_NGROUPS_MAX,
 619                 .procname       = "ngroups_max",
 620                 .data           = &ngroups_max,
 621                 .maxlen         = sizeof (int),
 622                 .mode           = 0444,
 623                 .proc_handler   = &proc_dointvec,
 624         },
 625 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 626         {
 627                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 628                 .procname       = "unknown_nmi_panic",
 629                 .data           = &unknown_nmi_panic,
 630                 .maxlen         = sizeof (int),
 631                 .mode           = 0644,
 632                 .proc_handler   = &proc_dointvec,
 633         },
 634         {
 635                 .ctl_name       = KERN_NMI_WATCHDOG,
 636                 .procname       = "nmi_watchdog",
 637                 .data           = &nmi_watchdog_enabled,
 638                 .maxlen         = sizeof (int),
 639                 .mode           = 0644,
 640                 .proc_handler   = &proc_nmi_enabled,
 641         },
 642 #endif
 643 #if defined(CONFIG_X86)
 644         {
 645                 .ctl_name       = KERN_PANIC_ON_NMI,
 646                 .procname       = "panic_on_unrecovered_nmi",
 647                 .data           = &panic_on_unrecovered_nmi,
 648                 .maxlen         = sizeof(int),
 649                 .mode           = 0644,
 650                 .proc_handler   = &proc_dointvec,
 651         },
 652         {
 653                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 654                 .procname       = "bootloader_type",
 655                 .data           = &bootloader_type,
 656                 .maxlen         = sizeof (int),
 657                 .mode           = 0444,
 658                 .proc_handler   = &proc_dointvec,
 659         },
 660 #endif
 661 #if defined(CONFIG_MMU)
 662         {
 663                 .ctl_name       = KERN_RANDOMIZE,
 664                 .procname       = "randomize_va_space",
 665                 .data           = &randomize_va_space,
 666                 .maxlen         = sizeof(int),
 667                 .mode           = 0644,
 668                 .proc_handler   = &proc_dointvec,
 669         },
 670 #endif
 671 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 672         {
 673                 .ctl_name       = KERN_SPIN_RETRY,
 674                 .procname       = "spin_retry",
 675                 .data           = &spin_retry,
 676                 .maxlen         = sizeof (int),
 677                 .mode           = 0644,
 678                 .proc_handler   = &proc_dointvec,
 679         },
 680 #endif
 681 #ifdef CONFIG_ACPI_SLEEP
 682         {
 683                 .ctl_name       = KERN_ACPI_VIDEO_FLAGS,
 684                 .procname       = "acpi_video_flags",
 685                 .data           = &acpi_video_flags,
 686                 .maxlen         = sizeof (unsigned long),
 687                 .mode           = 0644,
 688                 .proc_handler   = &proc_doulongvec_minmax,
 689         },
 690 #endif
 691 #ifdef CONFIG_IA64
 692         {
 693                 .ctl_name       = KERN_IA64_UNALIGNED,
 694                 .procname       = "ignore-unaligned-usertrap",
 695                 .data           = &no_unaligned_warning,
 696                 .maxlen         = sizeof (int),
 697                 .mode           = 0644,
 698                 .proc_handler   = &proc_dointvec,
 699         },
 700 #endif
 701 #ifdef CONFIG_COMPAT
 702         {
 703                 .ctl_name       = KERN_COMPAT_LOG,
 704                 .procname       = "compat-log",
 705                 .data           = &compat_log,
 706                 .maxlen         = sizeof (int),
 707                 .mode           = 0644,
 708                 .proc_handler   = &proc_dointvec,
 709         },
 710 #endif
 711 #ifdef CONFIG_RT_MUTEXES
 712         {
 713                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 714                 .procname       = "max_lock_depth",
 715                 .data           = &max_lock_depth,
 716                 .maxlen         = sizeof(int),
 717                 .mode           = 0644,
 718                 .proc_handler   = &proc_dointvec,
 719         },
 720 #endif
 721
 722         { .ctl_name = 0 }
 723 };
 724
 725 /* Constants for minimum and maximum testing in vm_table.
 726    We use these as one-element integer vectors. */
 727 static int zero;
 728 static int one_hundred = 100;
 729
 730
 731 static ctl_table vm_table[] = {
 732         {
 733                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 734                 .procname       = "overcommit_memory",
 735                 .data           = &sysctl_overcommit_memory,
 736                 .maxlen         = sizeof(sysctl_overcommit_memory),
 737                 .mode           = 0644,
 738                 .proc_handler   = &proc_dointvec,
 739         },
 740         {
 741                 .ctl_name       = VM_PANIC_ON_OOM,
 742                 .procname       = "panic_on_oom",
 743                 .data           = &sysctl_panic_on_oom,
 744                 .maxlen         = sizeof(sysctl_panic_on_oom),
 745                 .mode           = 0644,
 746                 .proc_handler   = &proc_dointvec,
 747         },
 748         {
 749                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 750                 .procname       = "overcommit_ratio",
 751                 .data           = &sysctl_overcommit_ratio,
 752                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 753                 .mode           = 0644,
 754                 .proc_handler   = &proc_dointvec,
 755         },
 756         {
 757                 .ctl_name       = VM_PAGE_CLUSTER,
 758                 .procname       = "page-cluster",
 759                 .data           = &page_cluster,
 760                 .maxlen         = sizeof(int),
 761                 .mode           = 0644,
 762                 .proc_handler   = &proc_dointvec,
 763         },
 764         {
 765                 .ctl_name       = VM_DIRTY_BACKGROUND,
 766                 .procname       = "dirty_background_ratio",
 767                 .data           = &dirty_background_ratio,
 768                 .maxlen         = sizeof(dirty_background_ratio),
 769                 .mode           = 0644,
 770                 .proc_handler   = &proc_dointvec_minmax,
 771                 .strategy       = &sysctl_intvec,
 772                 .extra1         = &zero,
 773                 .extra2         = &one_hundred,
 774         },
 775         {
 776                 .ctl_name       = VM_DIRTY_RATIO,
 777                 .procname       = "dirty_ratio",
 778                 .data           = &vm_dirty_ratio,
 779                 .maxlen         = sizeof(vm_dirty_ratio),
 780                 .mode           = 0644,
 781                 .proc_handler   = &proc_dointvec_minmax,
 782                 .strategy       = &sysctl_intvec,
 783                 .extra1         = &zero,
 784                 .extra2         = &one_hundred,
 785         },
 786         {
 787                 .ctl_name       = VM_DIRTY_WB_CS,
 788                 .procname       = "dirty_writeback_centisecs",
 789                 .data           = &dirty_writeback_interval,
 790                 .maxlen         = sizeof(dirty_writeback_interval),
 791                 .mode           = 0644,
 792                 .proc_handler   = &dirty_writeback_centisecs_handler,
 793         },
 794         {
 795                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 796                 .procname       = "dirty_expire_centisecs",
 797                 .data           = &dirty_expire_interval,
 798                 .maxlen         = sizeof(dirty_expire_interval),
 799                 .mode           = 0644,
 800                 .proc_handler   = &proc_dointvec_userhz_jiffies,
 801         },
 802         {
 803                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 804                 .procname       = "nr_pdflush_threads",
 805                 .data           = &nr_pdflush_threads,
 806                 .maxlen         = sizeof nr_pdflush_threads,
 807                 .mode           = 0444 /* read-only*/,
 808                 .proc_handler   = &proc_dointvec,
 809         },
 810         {
 811                 .ctl_name       = VM_SWAPPINESS,
 812                 .procname       = "swappiness",
 813                 .data           = &vm_swappiness,
 814                 .maxlen         = sizeof(vm_swappiness),
 815                 .mode           = 0644,
 816                 .proc_handler   = &proc_dointvec_minmax,
 817                 .strategy       = &sysctl_intvec,
 818                 .extra1         = &zero,
 819                 .extra2         = &one_hundred,
 820         },
 821 #ifdef CONFIG_HUGETLB_PAGE
 822          {
 823                 .ctl_name       = VM_HUGETLB_PAGES,
 824                 .procname       = "nr_hugepages",
 825                 .data           = &max_huge_pages,
 826                 .maxlen         = sizeof(unsigned long),
 827                 .mode           = 0644,
 828                 .proc_handler   = &hugetlb_sysctl_handler,
 829                 .extra1         = (void *)&hugetlb_zero,
 830                 .extra2         = (void *)&hugetlb_infinity,
 831          },
 832          {
 833                 .ctl_name       = VM_HUGETLB_GROUP,
 834                 .procname       = "hugetlb_shm_group",
 835                 .data           = &sysctl_hugetlb_shm_group,
 836                 .maxlen         = sizeof(gid_t),
 837                 .mode           = 0644,
 838                 .proc_handler   = &proc_dointvec,
 839          },
 840 #endif
 841         {
 842                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 843                 .procname       = "lowmem_reserve_ratio",
 844                 .data           = &sysctl_lowmem_reserve_ratio,
 845                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 846                 .mode           = 0644,
 847                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 848                 .strategy       = &sysctl_intvec,
 849         },
 850         {
 851                 .ctl_name       = VM_DROP_PAGECACHE,
 852                 .procname       = "drop_caches",
 853                 .data           = &sysctl_drop_caches,
 854                 .maxlen         = sizeof(int),
 855                 .mode           = 0644,
 856                 .proc_handler   = drop_caches_sysctl_handler,
 857                 .strategy       = &sysctl_intvec,
 858         },
 859         {
 860                 .ctl_name       = VM_MIN_FREE_KBYTES,
 861                 .procname       = "min_free_kbytes",
 862                 .data           = &min_free_kbytes,
 863                 .maxlen         = sizeof(min_free_kbytes),
 864                 .mode           = 0644,
 865                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 866                 .strategy       = &sysctl_intvec,
 867                 .extra1         = &zero,
 868         },
 869         {
 870                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
 871                 .procname       = "percpu_pagelist_fraction",
 872                 .data           = &percpu_pagelist_fraction,
 873                 .maxlen         = sizeof(percpu_pagelist_fraction),
 874                 .mode           = 0644,
 875                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
 876                 .strategy       = &sysctl_intvec,
 877                 .extra1         = &min_percpu_pagelist_fract,
 878         },
 879 #ifdef CONFIG_MMU
 880         {
 881                 .ctl_name       = VM_MAX_MAP_COUNT,
 882                 .procname       = "max_map_count",
 883                 .data           = &sysctl_max_map_count,
 884                 .maxlen         = sizeof(sysctl_max_map_count),
 885                 .mode           = 0644,
 886                 .proc_handler   = &proc_dointvec
 887         },
 888 #endif
 889         {
 890                 .ctl_name       = VM_LAPTOP_MODE,
 891                 .procname       = "laptop_mode",
 892                 .data           = &laptop_mode,
 893                 .maxlen         = sizeof(laptop_mode),
 894                 .mode           = 0644,
 895                 .proc_handler   = &proc_dointvec_jiffies,
 896                 .strategy       = &sysctl_jiffies,
 897         },
 898         {
 899                 .ctl_name       = VM_BLOCK_DUMP,
 900                 .procname       = "block_dump",
 901                 .data           = &block_dump,
 902                 .maxlen         = sizeof(block_dump),
 903                 .mode           = 0644,
 904                 .proc_handler   = &proc_dointvec,
 905                 .strategy       = &sysctl_intvec,
 906                 .extra1         = &zero,
 907         },
 908         {
 909                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 910                 .procname       = "vfs_cache_pressure",
 911                 .data           = &sysctl_vfs_cache_pressure,
 912                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 913                 .mode           = 0644,
 914                 .proc_handler   = &proc_dointvec,
 915                 .strategy       = &sysctl_intvec,
 916                 .extra1         = &zero,
 917         },
 918 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 919         {
 920                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 921                 .procname       = "legacy_va_layout",
 922                 .data           = &sysctl_legacy_va_layout,
 923                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 924                 .mode           = 0644,
 925                 .proc_handler   = &proc_dointvec,
 926                 .strategy       = &sysctl_intvec,
 927                 .extra1         = &zero,
 928         },
 929 #endif
 930 #ifdef CONFIG_SWAP
 931         {
 932                 .ctl_name       = VM_SWAP_TOKEN_TIMEOUT,
 933                 .procname       = "swap_token_timeout",
 934                 .data           = &swap_token_default_timeout,
 935                 .maxlen         = sizeof(swap_token_default_timeout),
 936                 .mode           = 0644,
 937                 .proc_handler   = &proc_dointvec_jiffies,
 938                 .strategy       = &sysctl_jiffies,
 939         },
 940 #endif
 941 #ifdef CONFIG_NUMA
 942         {
 943                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
 944                 .procname       = "zone_reclaim_mode",
 945                 .data           = &zone_reclaim_mode,
 946                 .maxlen         = sizeof(zone_reclaim_mode),
 947                 .mode           = 0644,
 948                 .proc_handler   = &proc_dointvec,
 949                 .strategy       = &sysctl_intvec,
 950                 .extra1         = &zero,
 951         },
 952         {
 953                 .ctl_name       = VM_MIN_UNMAPPED,
 954                 .procname       = "min_unmapped_ratio",
 955                 .data           = &sysctl_min_unmapped_ratio,
 956                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
 957                 .mode           = 0644,
 958                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
 959                 .strategy       = &sysctl_intvec,
 960                 .extra1         = &zero,
 961                 .extra2         = &one_hundred,
 962         },
 963         {
 964                 .ctl_name       = VM_MIN_SLAB,
 965                 .procname       = "min_slab_ratio",
 966                 .data           = &sysctl_min_slab_ratio,
 967                 .maxlen         = sizeof(sysctl_min_slab_ratio),
 968                 .mode           = 0644,
 969                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
 970                 .strategy       = &sysctl_intvec,
 971                 .extra1         = &zero,
 972                 .extra2         = &one_hundred,
 973         },
 974 #endif
 975 #ifdef CONFIG_X86_32
 976         {
 977                 .ctl_name       = VM_VDSO_ENABLED,
 978                 .procname       = "vdso_enabled",
 979                 .data           = &vdso_enabled,
 980                 .maxlen         = sizeof(vdso_enabled),
 981                 .mode           = 0644,
 982                 .proc_handler   = &proc_dointvec,
 983                 .strategy       = &sysctl_intvec,
 984                 .extra1         = &zero,
 985         },
 986 #endif
 987         { .ctl_name = 0 }
 988 };
 989
 990 static ctl_table fs_table[] = {
 991         {
 992                 .ctl_name       = FS_NRINODE,
 993                 .procname       = "inode-nr",
 994                 .data           = &inodes_stat,
 995                 .maxlen         = 2*sizeof(int),
 996                 .mode           = 0444,
 997                 .proc_handler   = &proc_dointvec,
 998         },
 999         {
1000                 .ctl_name       = FS_STATINODE,
1001                 .procname       = "inode-state",
1002                 .data           = &inodes_stat,
1003                 .maxlen         = 7*sizeof(int),
1004                 .mode           = 0444,
1005                 .proc_handler   = &proc_dointvec,
1006         },
1007         {
1008                 .ctl_name       = FS_NRFILE,
1009                 .procname       = "file-nr",
1010                 .data           = &files_stat,
1011                 .maxlen         = 3*sizeof(int),
1012                 .mode           = 0444,
1013                 .proc_handler   = &proc_nr_files,
1014         },
1015         {
1016                 .ctl_name       = FS_MAXFILE,
1017                 .procname       = "file-max",
1018                 .data           = &files_stat.max_files,
1019                 .maxlen         = sizeof(int),
1020                 .mode           = 0644,
1021                 .proc_handler   = &proc_dointvec,
1022         },
1023         {
1024                 .ctl_name       = FS_DENTRY,
1025                 .procname       = "dentry-state",
1026                 .data           = &dentry_stat,
1027                 .maxlen         = 6*sizeof(int),
1028                 .mode           = 0444,
1029                 .proc_handler   = &proc_dointvec,
1030         },
1031         {
1032                 .ctl_name       = FS_OVERFLOWUID,
1033                 .procname       = "overflowuid",
1034                 .data           = &fs_overflowuid,
1035                 .maxlen         = sizeof(int),
1036                 .mode           = 0644,
1037                 .proc_handler   = &proc_dointvec_minmax,
1038                 .strategy       = &sysctl_intvec,
1039                 .extra1         = &minolduid,
1040                 .extra2         = &maxolduid,
1041         },
1042         {
1043                 .ctl_name       = FS_OVERFLOWGID,
1044                 .procname       = "overflowgid",
1045                 .data           = &fs_overflowgid,
1046                 .maxlen         = sizeof(int),
1047                 .mode           = 0644,
1048                 .proc_handler   = &proc_dointvec_minmax,
1049                 .strategy       = &sysctl_intvec,
1050                 .extra1         = &minolduid,
1051                 .extra2         = &maxolduid,
1052         },
1053         {
1054                 .ctl_name       = FS_LEASES,
1055                 .procname       = "leases-enable",
1056                 .data           = &leases_enable,
1057                 .maxlen         = sizeof(int),
1058                 .mode           = 0644,
1059                 .proc_handler   = &proc_dointvec,
1060         },
1061 #ifdef CONFIG_DNOTIFY
1062         {
1063                 .ctl_name       = FS_DIR_NOTIFY,
1064                 .procname       = "dir-notify-enable",
1065                 .data           = &dir_notify_enable,
1066                 .maxlen         = sizeof(int),
1067                 .mode           = 0644,
1068                 .proc_handler   = &proc_dointvec,
1069         },
1070 #endif
1071 #ifdef CONFIG_MMU
1072         {
1073                 .ctl_name       = FS_LEASE_TIME,
1074                 .procname       = "lease-break-time",
1075                 .data           = &lease_break_time,
1076                 .maxlen         = sizeof(int),
1077                 .mode           = 0644,
1078                 .proc_handler   = &proc_dointvec,
1079         },
1080         {
1081                 .ctl_name       = FS_AIO_NR,
1082                 .procname       = "aio-nr",
1083                 .data           = &aio_nr,
1084                 .maxlen         = sizeof(aio_nr),
1085                 .mode           = 0444,
1086                 .proc_handler   = &proc_doulongvec_minmax,
1087         },
1088         {
1089                 .ctl_name       = FS_AIO_MAX_NR,
1090                 .procname       = "aio-max-nr",
1091                 .data           = &aio_max_nr,
1092                 .maxlen         = sizeof(aio_max_nr),
1093                 .mode           = 0644,
1094                 .proc_handler   = &proc_doulongvec_minmax,
1095         },
1096 #ifdef CONFIG_INOTIFY_USER
1097         {
1098                 .ctl_name       = FS_INOTIFY,
1099                 .procname       = "inotify",
1100                 .mode           = 0555,
1101                 .child          = inotify_table,
1102         },
1103 #endif
1104 #endif
1105         {
1106                 .ctl_name       = KERN_SETUID_DUMPABLE,
1107                 .procname       = "suid_dumpable",
1108                 .data           = &suid_dumpable,
1109                 .maxlen         = sizeof(int),
1110                 .mode           = 0644,
1111                 .proc_handler   = &proc_dointvec,
1112         },
1113         { .ctl_name = 0 }
1114 };
1115
1116 static ctl_table debug_table[] = {
1117         { .ctl_name = 0 }
1118 };
1119
1120 static ctl_table dev_table[] = {
1121         { .ctl_name = 0 }
1122 };
1123
1124 extern void init_irq_proc (void);
1125
1126 static DEFINE_SPINLOCK(sysctl_lock);
1127
1128 /* called under sysctl_lock */
1129 static int use_table(struct ctl_table_header *p)
1130 {
1131         if (unlikely(p->unregistering))
1132                 return 0;
1133         p->used++;
1134         return 1;
1135 }
1136
1137 /* called under sysctl_lock */
1138 static void unuse_table(struct ctl_table_header *p)
1139 {
1140         if (!--p->used)
1141                 if (unlikely(p->unregistering))
1142                         complete(p->unregistering);
1143 }
1144
1145 /* called under sysctl_lock, will reacquire if has to wait */
1146 static void start_unregistering(struct ctl_table_header *p)
1147 {
1148         /*
1149          * if p->used is 0, nobody will ever touch that entry again;
1150          * we'll eliminate all paths to it before dropping sysctl_lock
1151          */
1152         if (unlikely(p->used)) {
1153                 struct completion wait;
1154                 init_completion(&wait);
1155                 p->unregistering = &wait;
1156                 spin_unlock(&sysctl_lock);
1157                 wait_for_completion(&wait);
1158                 spin_lock(&sysctl_lock);
1159         }
1160         /*
1161          * do not remove from the list until nobody holds it; walking the
1162          * list in do_sysctl() relies on that.
1163          */
1164         list_del_init(&p->ctl_entry);
1165 }
1166
1167 void __init sysctl_init(void)
1168 {
1169 #ifdef CONFIG_PROC_SYSCTL
1170         register_proc_table(root_table, proc_sys_root, &root_table_header);
1171         init_irq_proc();
1172 #endif
1173 }
1174
1175 #ifdef CONFIG_SYSCTL_SYSCALL
1176 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1177                void __user *newval, size_t newlen)
1178 {
1179         struct list_head *tmp;
1180         int error = -ENOTDIR;
1181
1182         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1183                 return -ENOTDIR;
1184         if (oldval) {
1185                 int old_len;
1186                 if (!oldlenp || get_user(old_len, oldlenp))
1187                         return -EFAULT;
1188         }
1189         spin_lock(&sysctl_lock);
1190         tmp = &root_table_header.ctl_entry;
1191         do {
1192                 struct ctl_table_header *head =
1193                         list_entry(tmp, struct ctl_table_header, ctl_entry);
1194                 void *context = NULL;
1195
1196                 if (!use_table(head))
1197                         continue;
1198
1199                 spin_unlock(&sysctl_lock);
1200
1201                 error = parse_table(name, nlen, oldval, oldlenp,
1202                                         newval, newlen, head->ctl_table,
1203                                         &context);
1204                 kfree(context);
1205
1206                 spin_lock(&sysctl_lock);
1207                 unuse_table(head);
1208                 if (error != -ENOTDIR)
1209                         break;
1210         } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1211         spin_unlock(&sysctl_lock);
1212         return error;
1213 }
1214
1215 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1216 {
1217         struct __sysctl_args tmp;
1218         int error;
1219
1220         if (copy_from_user(&tmp, args, sizeof(tmp)))
1221                 return -EFAULT;
1222
1223         lock_kernel();
1224         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1225                           tmp.newval, tmp.newlen);
1226         unlock_kernel();
1227         return error;
1228 }
1229 #endif /* CONFIG_SYSCTL_SYSCALL */
1230
1231 /*
1232  * ctl_perm does NOT grant the superuser all rights automatically, because
1233  * some sysctl variables are readonly even to root.
1234  */
1235
1236 static int test_perm(int mode, int op)
1237 {
1238         if (!current->euid)
1239                 mode >>= 6;
1240         else if (in_egroup_p(0))
1241                 mode >>= 3;
1242         if ((mode & op & 0007) == op)
1243                 return 0;
1244         return -EACCES;
1245 }
1246
1247 static inline int ctl_perm(ctl_table *table, int op)
1248 {
1249         int error;
1250         error = security_sysctl(table, op);
1251         if (error)
1252                 return error;
1253         return test_perm(table->mode, op);
1254 }
1255
1256 #ifdef CONFIG_SYSCTL_SYSCALL
1257 static int parse_table(int __user *name, int nlen,
1258                        void __user *oldval, size_t __user *oldlenp,
1259                        void __user *newval, size_t newlen,
1260                        ctl_table *table, void **context)
1261 {
1262         int n;
1263 repeat:
1264         if (!nlen)
1265                 return -ENOTDIR;
1266         if (get_user(n, name))
1267                 return -EFAULT;
1268         for ( ; table->ctl_name; table++) {
1269                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1270                         int error;
1271                         if (table->child) {
1272                                 if (ctl_perm(table, 001))
1273                                         return -EPERM;
1274                                 if (table->strategy) {
1275                                         error = table->strategy(
1276                                                 table, name, nlen,
1277                                                 oldval, oldlenp,
1278                                                 newval, newlen, context);
1279                                         if (error)
1280                                                 return error;
1281                                 }
1282                                 name++;
1283                                 nlen--;
1284                                 table = table->child;
1285                                 goto repeat;
1286                         }
1287                         error = do_sysctl_strategy(table, name, nlen,
1288                                                    oldval, oldlenp,
1289                                                    newval, newlen, context);
1290                         return error;
1291                 }
1292         }
1293         return -ENOTDIR;
1294 }
1295
1296 /* Perform the actual read/write of a sysctl table entry. */
1297 int do_sysctl_strategy (ctl_table *table,
1298                         int __user *name, int nlen,
1299                         void __user *oldval, size_t __user *oldlenp,
1300                         void __user *newval, size_t newlen, void **context)
1301 {
1302         int op = 0, rc;
1303         size_t len;
1304
1305         if (oldval)
1306                 op |= 004;
1307         if (newval)
1308                 op |= 002;
1309         if (ctl_perm(table, op))
1310                 return -EPERM;
1311
1312         if (table->strategy) {
1313                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1314                                      newval, newlen, context);
1315                 if (rc < 0)
1316                         return rc;
1317                 if (rc > 0)
1318                         return 0;
1319         }
1320
1321         /* If there is no strategy routine, or if the strategy returns
1322          * zero, proceed with automatic r/w */
1323         if (table->data && table->maxlen) {
1324                 if (oldval && oldlenp) {
1325                         if (get_user(len, oldlenp))
1326                                 return -EFAULT;
1327                         if (len) {
1328                                 if (len > table->maxlen)
1329                                         len = table->maxlen;
1330                                 if(copy_to_user(oldval, table->data, len))
1331                                         return -EFAULT;
1332                                 if(put_user(len, oldlenp))
1333                                         return -EFAULT;
1334                         }
1335                 }
1336                 if (newval && newlen) {
1337                         len = newlen;
1338                         if (len > table->maxlen)
1339                                 len = table->maxlen;
1340                         if(copy_from_user(table->data, newval, len))
1341                                 return -EFAULT;
1342                 }
1343         }
1344         return 0;
1345 }
1346 #endif /* CONFIG_SYSCTL_SYSCALL */
1347
1348 /**
1349  * register_sysctl_table - register a sysctl hierarchy
1350  * @table: the top-level table structure
1351  * @insert_at_head: whether the entry should be inserted in front or at the end
1352  *
1353  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1354  * array. An entry with a ctl_name of 0 terminates the table.
1355  *
1356  * The members of the &ctl_table structure are used as follows:
1357  *
1358  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1359  *            must be unique within that level of sysctl
1360  *
1361  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1362  *            enter a sysctl file
1363  *
1364  * data - a pointer to data for use by proc_handler
1365  *
1366  * maxlen - the maximum size in bytes of the data
1367  *
1368  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1369  *
1370  * child - a pointer to the child sysctl table if this entry is a directory, or
1371  *         %NULL.
1372  *
1373  * proc_handler - the text handler routine (described below)
1374  *
1375  * strategy - the strategy routine (described below)
1376  *
1377  * de - for internal use by the sysctl routines
1378  *
1379  * extra1, extra2 - extra pointers usable by the proc handler routines
1380  *
1381  * Leaf nodes in the sysctl tree will be represented by a single file
1382  * under /proc; non-leaf nodes will be represented by directories.
1383  *
1384  * sysctl(2) can automatically manage read and write requests through
1385  * the sysctl table.  The data and maxlen fields of the ctl_table
1386  * struct enable minimal validation of the values being written to be
1387  * performed, and the mode field allows minimal authentication.
1388  *
1389  * More sophisticated management can be enabled by the provision of a
1390  * strategy routine with the table entry.  This will be called before
1391  * any automatic read or write of the data is performed.
1392  *
1393  * The strategy routine may return
1394  *
1395  * < 0 - Error occurred (error is passed to user process)
1396  *
1397  * 0   - OK - proceed with automatic read or write.
1398  *
1399  * > 0 - OK - read or write has been done by the strategy routine, so
1400  *       return immediately.
1401  *
1402  * There must be a proc_handler routine for any terminal nodes
1403  * mirrored under /proc/sys (non-terminals are handled by a built-in
1404  * directory handler).  Several default handlers are available to
1405  * cover common cases -
1406  *
1407  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1408  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1409  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1410  *
1411  * It is the handler's job to read the input buffer from user memory
1412  * and process it. The handler should return 0 on success.
1413  *
1414  * This routine returns %NULL on a failure to register, and a pointer
1415  * to the table header on success.
1416  */
1417 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1418                                                int insert_at_head)
1419 {
1420         struct ctl_table_header *tmp;
1421         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1422         if (!tmp)
1423                 return NULL;
1424         tmp->ctl_table = table;
1425         INIT_LIST_HEAD(&tmp->ctl_entry);
1426         tmp->used = 0;
1427         tmp->unregistering = NULL;
1428         spin_lock(&sysctl_lock);
1429         if (insert_at_head)
1430                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1431         else
1432                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1433         spin_unlock(&sysctl_lock);
1434 #ifdef CONFIG_PROC_SYSCTL
1435         register_proc_table(table, proc_sys_root, tmp);
1436 #endif
1437         return tmp;
1438 }
1439
1440 /**
1441  * unregister_sysctl_table - unregister a sysctl table hierarchy
1442  * @header: the header returned from register_sysctl_table
1443  *
1444  * Unregisters the sysctl table and all children. proc entries may not
1445  * actually be removed until they are no longer used by anyone.
1446  */
1447 void unregister_sysctl_table(struct ctl_table_header * header)
1448 {
1449         might_sleep();
1450         spin_lock(&sysctl_lock);
1451         start_unregistering(header);
1452 #ifdef CONFIG_PROC_SYSCTL
1453         unregister_proc_table(header->ctl_table, proc_sys_root);
1454 #endif
1455         spin_unlock(&sysctl_lock);
1456         kfree(header);
1457 }
1458
1459 #else /* !CONFIG_SYSCTL */
1460 struct ctl_table_header * register_sysctl_table(ctl_table * table,
1461                                                 int insert_at_head)
1462 {
1463         return NULL;
1464 }
1465
1466 void unregister_sysctl_table(struct ctl_table_header * table)
1467 {
1468 }
1469
1470 #endif /* CONFIG_SYSCTL */
1471
1472 /*
1473  * /proc/sys support
1474  */
1475
1476 #ifdef CONFIG_PROC_SYSCTL
1477
1478 /* Scan the sysctl entries in table and add them all into /proc */
1479 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1480 {
1481         struct proc_dir_entry *de;
1482         int len;
1483         mode_t mode;
1484
1485         for (; table->ctl_name; table++) {
1486                 /* Can't do anything without a proc name. */
1487                 if (!table->procname)
1488                         continue;
1489                 /* Maybe we can't do anything with it... */
1490                 if (!table->proc_handler && !table->child) {
1491                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1492                                 table->procname);
1493                         continue;
1494                 }
1495
1496                 len = strlen(table->procname);
1497                 mode = table->mode;
1498
1499                 de = NULL;
1500                 if (table->proc_handler)
1501                         mode |= S_IFREG;
1502                 else {
1503                         mode |= S_IFDIR;
1504                         for (de = root->subdir; de; de = de->next) {
1505                                 if (proc_match(len, table->procname, de))
1506                                         break;
1507                         }
1508                         /* If the subdir exists already, de is non-NULL */
1509                 }
1510
1511                 if (!de) {
1512                         de = create_proc_entry(table->procname, mode, root);
1513                         if (!de)
1514                                 continue;
1515                         de->set = set;
1516                         de->data = (void *) table;
1517                         if (table->proc_handler)
1518                                 de->proc_fops = &proc_sys_file_operations;
1519                 }
1520                 table->de = de;
1521                 if (de->mode & S_IFDIR)
1522                         register_proc_table(table->child, de, set);
1523         }
1524 }
1525
1526 /*
1527  * Unregister a /proc sysctl table and any subdirectories.
1528  */
1529 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1530 {
1531         struct proc_dir_entry *de;
1532         for (; table->ctl_name; table++) {
1533                 if (!(de = table->de))
1534                         continue;
1535                 if (de->mode & S_IFDIR) {
1536                         if (!table->child) {
1537                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1538                                 continue;
1539                         }
1540                         unregister_proc_table(table->child, de);
1541
1542                         /* Don't unregister directories which still have entries.. */
1543                         if (de->subdir)
1544                                 continue;
1545                 }
1546
1547                 /*
1548                  * In any case, mark the entry as goner; we'll keep it
1549                  * around if it's busy, but we'll know to do nothing with
1550                  * its fields.  We are under sysctl_lock here.
1551                  */
1552                 de->data = NULL;
1553
1554                 /* Don't unregister proc entries that are still being used.. */
1555                 if (atomic_read(&de->count))
1556                         continue;
1557
1558                 table->de = NULL;
1559                 remove_proc_entry(table->procname, root);
1560         }
1561 }
1562
1563 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1564                           size_t count, loff_t *ppos)
1565 {
1566         int op;
1567         struct proc_dir_entry *de = PDE(file->f_dentry->d_inode);
1568         struct ctl_table *table;
1569         size_t res;
1570         ssize_t error = -ENOTDIR;
1571
1572         spin_lock(&sysctl_lock);
1573         if (de && de->data && use_table(de->set)) {
1574                 /*
1575                  * at that point we know that sysctl was not unregistered
1576                  * and won't be until we finish
1577                  */
1578                 spin_unlock(&sysctl_lock);
1579                 table = (struct ctl_table *) de->data;
1580                 if (!table || !table->proc_handler)
1581                         goto out;
1582                 error = -EPERM;
1583                 op = (write ? 002 : 004);
1584                 if (ctl_perm(table, op))
1585                         goto out;
1586
1587                 /* careful: calling conventions are nasty here */
1588                 res = count;
1589                 error = (*table->proc_handler)(table, write, file,
1590                                                 buf, &res, ppos);
1591                 if (!error)
1592                         error = res;
1593         out:
1594                 spin_lock(&sysctl_lock);
1595                 unuse_table(de->set);
1596         }
1597         spin_unlock(&sysctl_lock);
1598         return error;
1599 }
1600
1601 static int proc_opensys(struct inode *inode, struct file *file)
1602 {
1603         if (file->f_mode & FMODE_WRITE) {
1604                 /*
1605                  * sysctl entries that are not writable,
1606                  * are _NOT_ writable, capabilities or not.
1607                  */
1608                 if (!(inode->i_mode & S_IWUSR))
1609                         return -EPERM;
1610         }
1611
1612         return 0;
1613 }
1614
1615 static ssize_t proc_readsys(struct file * file, char __user * buf,
1616                             size_t count, loff_t *ppos)
1617 {
1618         return do_rw_proc(0, file, buf, count, ppos);
1619 }
1620
1621 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1622                              size_t count, loff_t *ppos)
1623 {
1624         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1625 }
1626
1627 int _proc_do_string(void* data, int maxlen, int write, struct file *filp,
1628                     void __user *buffer, size_t *lenp, loff_t *ppos)
1629 {
1630         size_t len;
1631         char __user *p;
1632         char c;
1633
1634         if (!data || !maxlen || !*lenp ||
1635             (*ppos && !write)) {
1636                 *lenp = 0;
1637                 return 0;
1638         }
1639
1640         if (write) {
1641                 len = 0;
1642                 p = buffer;
1643                 while (len < *lenp) {
1644                         if (get_user(c, p++))
1645                                 return -EFAULT;
1646                         if (c == 0 || c == '\n')
1647                                 break;
1648                         len++;
1649                 }
1650                 if (len >= maxlen)
1651                         len = maxlen-1;
1652                 if(copy_from_user(data, buffer, len))
1653                         return -EFAULT;
1654                 ((char *) data)[len] = 0;
1655                 *ppos += *lenp;
1656         } else {
1657                 len = strlen(data);
1658                 if (len > maxlen)
1659                         len = maxlen;
1660                 if (len > *lenp)
1661                         len = *lenp;
1662                 if (len)
1663                         if(copy_to_user(buffer, data, len))
1664                                 return -EFAULT;
1665                 if (len < *lenp) {
1666                         if(put_user('\n', ((char __user *) buffer) + len))
1667                                 return -EFAULT;
1668                         len++;
1669                 }
1670                 *lenp = len;
1671                 *ppos += len;
1672         }
1673         return 0;
1674 }
1675
1676 /**
1677  * proc_dostring - read a string sysctl
1678  * @table: the sysctl table
1679  * @write: %TRUE if this is a write to the sysctl file
1680  * @filp: the file structure
1681  * @buffer: the user buffer
1682  * @lenp: the size of the user buffer
1683  * @ppos: file position
1684  *
1685  * Reads/writes a string from/to the user buffer. If the kernel
1686  * buffer provided is not large enough to hold the string, the
1687  * string is truncated. The copied string is %NULL-terminated.
1688  * If the string is being read by the user process, it is copied
1689  * and a newline '\n' is added. It is truncated if the buffer is
1690  * not large enough.
1691  *
1692  * Returns 0 on success.
1693  */
1694 int proc_dostring(ctl_table *table, int write, struct file *filp,
1695                   void __user *buffer, size_t *lenp, loff_t *ppos)
1696 {
1697         return _proc_do_string(table->data, table->maxlen, write, filp,
1698                                buffer, lenp, ppos);
1699 }
1700
1701 /*
1702  *      Special case of dostring for the UTS structure. This has locks
1703  *      to observe. Should this be in kernel/sys.c ????
1704  */
1705
1706 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1707                   void __user *buffer, size_t *lenp, loff_t *ppos)
1708 {
1709         int r;
1710
1711         if (!write) {
1712                 down_read(&uts_sem);
1713                 r=proc_dostring(table,0,filp,buffer,lenp, ppos);
1714                 up_read(&uts_sem);
1715         } else {
1716                 down_write(&uts_sem);
1717                 r=proc_dostring(table,1,filp,buffer,lenp, ppos);
1718                 up_write(&uts_sem);
1719         }
1720         return r;
1721 }
1722
1723 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1724                                  int *valp,
1725                                  int write, void *data)
1726 {
1727         if (write) {
1728                 *valp = *negp ? -*lvalp : *lvalp;
1729         } else {
1730                 int val = *valp;
1731                 if (val < 0) {
1732                         *negp = -1;
1733                         *lvalp = (unsigned long)-val;
1734                 } else {
1735                         *negp = 0;
1736                         *lvalp = (unsigned long)val;
1737                 }
1738         }
1739         return 0;
1740 }
1741
1742 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1743                   void __user *buffer, size_t *lenp, loff_t *ppos,
1744                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1745                               int write, void *data),
1746                   void *data)
1747 {
1748 #define TMPBUFLEN 21
1749         int *i, vleft, first=1, neg, val;
1750         unsigned long lval;
1751         size_t left, len;
1752
1753         char buf[TMPBUFLEN], *p;
1754         char __user *s = buffer;
1755
1756         if (!table->data || !table->maxlen || !*lenp ||
1757             (*ppos && !write)) {
1758                 *lenp = 0;
1759                 return 0;
1760         }
1761
1762         i = (int *) table->data;
1763         vleft = table->maxlen / sizeof(*i);
1764         left = *lenp;
1765
1766         if (!conv)
1767                 conv = do_proc_dointvec_conv;
1768
1769         for (; left && vleft--; i++, first=0) {
1770                 if (write) {
1771                         while (left) {
1772                                 char c;
1773                                 if (get_user(c, s))
1774                                         return -EFAULT;
1775                                 if (!isspace(c))
1776                                         break;
1777                                 left--;
1778                                 s++;
1779                         }
1780                         if (!left)
1781                                 break;
1782                         neg = 0;
1783                         len = left;
1784                         if (len > sizeof(buf) - 1)
1785                                 len = sizeof(buf) - 1;
1786                         if (copy_from_user(buf, s, len))
1787                                 return -EFAULT;
1788                         buf[len] = 0;
1789                         p = buf;
1790                         if (*p == '-' && left > 1) {
1791                                 neg = 1;
1792                                 left--, p++;
1793                         }
1794                         if (*p < '0' || *p > '9')
1795                                 break;
1796
1797                         lval = simple_strtoul(p, &p, 0);
1798
1799                         len = p-buf;
1800                         if ((len < left) && *p && !isspace(*p))
1801                                 break;
1802                         if (neg)
1803                                 val = -val;
1804                         s += len;
1805                         left -= len;
1806
1807                         if (conv(&neg, &lval, i, 1, data))
1808                                 break;
1809                 } else {
1810                         p = buf;
1811                         if (!first)
1812                                 *p++ = '\t';
1813
1814                         if (conv(&neg, &lval, i, 0, data))
1815                                 break;
1816
1817                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1818                         len = strlen(buf);
1819                         if (len > left)
1820                                 len = left;
1821                         if(copy_to_user(s, buf, len))
1822                                 return -EFAULT;
1823                         left -= len;
1824                         s += len;
1825                 }
1826         }
1827
1828         if (!write && !first && left) {
1829                 if(put_user('\n', s))
1830                         return -EFAULT;
1831                 left--, s++;
1832         }
1833         if (write) {
1834                 while (left) {
1835                         char c;
1836                         if (get_user(c, s++))
1837                                 return -EFAULT;
1838                         if (!isspace(c))
1839                                 break;
1840                         left--;
1841                 }
1842         }
1843         if (write && first)
1844                 return -EINVAL;
1845         *lenp -= left;
1846         *ppos += *lenp;
1847         return 0;
1848 #undef TMPBUFLEN
1849 }
1850
1851 /**
1852  * proc_dointvec - read a vector of integers
1853  * @table: the sysctl table
1854  * @write: %TRUE if this is a write to the sysctl file
1855  * @filp: the file structure
1856  * @buffer: the user buffer
1857  * @lenp: the size of the user buffer
1858  * @ppos: file position
1859  *
1860  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1861  * values from/to the user buffer, treated as an ASCII string.
1862  *
1863  * Returns 0 on success.
1864  */
1865 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1866                      void __user *buffer, size_t *lenp, loff_t *ppos)
1867 {
1868     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1869                             NULL,NULL);
1870 }
1871
1872 #define OP_SET  0
1873 #define OP_AND  1
1874 #define OP_OR   2
1875 #define OP_MAX  3
1876 #define OP_MIN  4
1877
1878 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1879                                       int *valp,
1880                                       int write, void *data)
1881 {
1882         int op = *(int *)data;
1883         if (write) {
1884                 int val = *negp ? -*lvalp : *lvalp;
1885                 switch(op) {
1886                 case OP_SET:    *valp = val; break;
1887                 case OP_AND:    *valp &= val; break;
1888                 case OP_OR:     *valp |= val; break;
1889                 case OP_MAX:    if(*valp < val)
1890                                         *valp = val;
1891                                 break;
1892                 case OP_MIN:    if(*valp > val)
1893                                 *valp = val;
1894                                 break;
1895                 }
1896         } else {
1897                 int val = *valp;
1898                 if (val < 0) {
1899                         *negp = -1;
1900                         *lvalp = (unsigned long)-val;
1901                 } else {
1902                         *negp = 0;
1903                         *lvalp = (unsigned long)val;
1904                 }
1905         }
1906         return 0;
1907 }
1908
1909 /*
1910  *      init may raise the set.
1911  */
1912
1913 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1914                         void __user *buffer, size_t *lenp, loff_t *ppos)
1915 {
1916         int op;
1917
1918         if (!capable(CAP_SYS_MODULE)) {
1919                 return -EPERM;
1920         }
1921
1922         op = is_init(current) ? OP_SET : OP_AND;
1923         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1924                                 do_proc_dointvec_bset_conv,&op);
1925 }
1926
1927 struct do_proc_dointvec_minmax_conv_param {
1928         int *min;
1929         int *max;
1930 };
1931
1932 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1933                                         int *valp,
1934                                         int write, void *data)
1935 {
1936         struct do_proc_dointvec_minmax_conv_param *param = data;
1937         if (write) {
1938                 int val = *negp ? -*lvalp : *lvalp;
1939                 if ((param->min && *param->min > val) ||
1940                     (param->max && *param->max < val))
1941                         return -EINVAL;
1942                 *valp = val;
1943         } else {
1944                 int val = *valp;
1945                 if (val < 0) {
1946                         *negp = -1;
1947                         *lvalp = (unsigned long)-val;
1948                 } else {
1949                         *negp = 0;
1950                         *lvalp = (unsigned long)val;
1951                 }
1952         }
1953         return 0;
1954 }
1955
1956 /**
1957  * proc_dointvec_minmax - read a vector of integers with min/max values
1958  * @table: the sysctl table
1959  * @write: %TRUE if this is a write to the sysctl file
1960  * @filp: the file structure
1961  * @buffer: the user buffer
1962  * @lenp: the size of the user buffer
1963  * @ppos: file position
1964  *
1965  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1966  * values from/to the user buffer, treated as an ASCII string.
1967  *
1968  * This routine will ensure the values are within the range specified by
1969  * table->extra1 (min) and table->extra2 (max).
1970  *
1971  * Returns 0 on success.
1972  */
1973 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1974                   void __user *buffer, size_t *lenp, loff_t *ppos)
1975 {
1976         struct do_proc_dointvec_minmax_conv_param param = {
1977                 .min = (int *) table->extra1,
1978                 .max = (int *) table->extra2,
1979         };
1980         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1981                                 do_proc_dointvec_minmax_conv, &param);
1982 }
1983
1984 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1985                                      struct file *filp,
1986                                      void __user *buffer,
1987                                      size_t *lenp, loff_t *ppos,
1988                                      unsigned long convmul,
1989                                      unsigned long convdiv)
1990 {
1991 #define TMPBUFLEN 21
1992         unsigned long *i, *min, *max, val;
1993         int vleft, first=1, neg;
1994         size_t len, left;
1995         char buf[TMPBUFLEN], *p;
1996         char __user *s = buffer;
1997
1998         if (!table->data || !table->maxlen || !*lenp ||
1999             (*ppos && !write)) {
2000                 *lenp = 0;
2001                 return 0;
2002         }
2003
2004         i = (unsigned long *) table->data;
2005         min = (unsigned long *) table->extra1;
2006         max = (unsigned long *) table->extra2;
2007         vleft = table->maxlen / sizeof(unsigned long);
2008         left = *lenp;
2009
2010         for (; left && vleft--; i++, min++, max++, first=0) {
2011                 if (write) {
2012                         while (left) {
2013                                 char c;
2014                                 if (get_user(c, s))
2015                                         return -EFAULT;
2016                                 if (!isspace(c))
2017                                         break;
2018                                 left--;
2019                                 s++;
2020                         }
2021                         if (!left)
2022                                 break;
2023                         neg = 0;
2024                         len = left;
2025                         if (len > TMPBUFLEN-1)
2026                                 len = TMPBUFLEN-1;
2027                         if (copy_from_user(buf, s, len))
2028                                 return -EFAULT;
2029                         buf[len] = 0;
2030                         p = buf;
2031                         if (*p == '-' && left > 1) {
2032                                 neg = 1;
2033                                 left--, p++;
2034                         }
2035                         if (*p < '0' || *p > '9')
2036                                 break;
2037                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2038                         len = p-buf;
2039                         if ((len < left) && *p && !isspace(*p))
2040                                 break;
2041                         if (neg)
2042                                 val = -val;
2043                         s += len;
2044                         left -= len;
2045
2046                         if(neg)
2047                                 continue;
2048                         if ((min && val < *min) || (max && val > *max))
2049                                 continue;
2050                         *i = val;
2051                 } else {
2052                         p = buf;
2053                         if (!first)
2054                                 *p++ = '\t';
2055                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2056                         len = strlen(buf);
2057                         if (len > left)
2058                                 len = left;
2059                         if(copy_to_user(s, buf, len))
2060                                 return -EFAULT;
2061                         left -= len;
2062                         s += len;
2063                 }
2064         }
2065
2066         if (!write && !first && left) {
2067                 if(put_user('\n', s))
2068                         return -EFAULT;
2069                 left--, s++;
2070         }
2071         if (write) {
2072                 while (left) {
2073                         char c;
2074                         if (get_user(c, s++))
2075                                 return -EFAULT;
2076                         if (!isspace(c))
2077                                 break;
2078                         left--;
2079                 }
2080         }
2081         if (write && first)
2082                 return -EINVAL;
2083         *lenp -= left;
2084         *ppos += *lenp;
2085         return 0;
2086 #undef TMPBUFLEN
2087 }
2088
2089 /**
2090  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2091  * @table: the sysctl table
2092  * @write: %TRUE if this is a write to the sysctl file
2093  * @filp: the file structure
2094  * @buffer: the user buffer
2095  * @lenp: the size of the user buffer
2096  * @ppos: file position
2097  *
2098  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2099  * values from/to the user buffer, treated as an ASCII string.
2100  *
2101  * This routine will ensure the values are within the range specified by
2102  * table->extra1 (min) and table->extra2 (max).
2103  *
2104  * Returns 0 on success.
2105  */
2106 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2107                            void __user *buffer, size_t *lenp, loff_t *ppos)
2108 {
2109     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2110 }
2111
2112 /**
2113  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2114  * @table: the sysctl table
2115  * @write: %TRUE if this is a write to the sysctl file
2116  * @filp: the file structure
2117  * @buffer: the user buffer
2118  * @lenp: the size of the user buffer
2119  * @ppos: file position
2120  *
2121  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2122  * values from/to the user buffer, treated as an ASCII string. The values
2123  * are treated as milliseconds, and converted to jiffies when they are stored.
2124  *
2125  * This routine will ensure the values are within the range specified by
2126  * table->extra1 (min) and table->extra2 (max).
2127  *
2128  * Returns 0 on success.
2129  */
2130 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2131                                       struct file *filp,
2132                                       void __user *buffer,
2133                                       size_t *lenp, loff_t *ppos)
2134 {
2135     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2136                                      lenp, ppos, HZ, 1000l);
2137 }
2138
2139
2140 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2141                                          int *valp,
2142                                          int write, void *data)
2143 {
2144         if (write) {
2145                 if (*lvalp > LONG_MAX / HZ)
2146                         return 1;
2147                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2148         } else {
2149                 int val = *valp;
2150                 unsigned long lval;
2151                 if (val < 0) {
2152                         *negp = -1;
2153                         lval = (unsigned long)-val;
2154                 } else {
2155                         *negp = 0;
2156                         lval = (unsigned long)val;
2157                 }
2158                 *lvalp = lval / HZ;
2159         }
2160         return 0;
2161 }
2162
2163 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2164                                                 int *valp,
2165                                                 int write, void *data)
2166 {
2167         if (write) {
2168                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2169                         return 1;
2170                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2171         } else {
2172                 int val = *valp;
2173                 unsigned long lval;
2174                 if (val < 0) {
2175                         *negp = -1;
2176                         lval = (unsigned long)-val;
2177                 } else {
2178                         *negp = 0;
2179                         lval = (unsigned long)val;
2180                 }
2181                 *lvalp = jiffies_to_clock_t(lval);
2182         }
2183         return 0;
2184 }
2185
2186 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2187                                             int *valp,
2188                                             int write, void *data)
2189 {
2190         if (write) {
2191                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2192         } else {
2193                 int val = *valp;
2194                 unsigned long lval;
2195                 if (val < 0) {
2196                         *negp = -1;
2197                         lval = (unsigned long)-val;
2198                 } else {
2199                         *negp = 0;
2200                         lval = (unsigned long)val;
2201                 }
2202                 *lvalp = jiffies_to_msecs(lval);
2203         }
2204         return 0;
2205 }
2206
2207 /**
2208  * proc_dointvec_jiffies - read a vector of integers as seconds
2209  * @table: the sysctl table
2210  * @write: %TRUE if this is a write to the sysctl file
2211  * @filp: the file structure
2212  * @buffer: the user buffer
2213  * @lenp: the size of the user buffer
2214  * @ppos: file position
2215  *
2216  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2217  * values from/to the user buffer, treated as an ASCII string.
2218  * The values read are assumed to be in seconds, and are converted into
2219  * jiffies.
2220  *
2221  * Returns 0 on success.
2222  */
2223 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2224                           void __user *buffer, size_t *lenp, loff_t *ppos)
2225 {
2226     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2227                             do_proc_dointvec_jiffies_conv,NULL);
2228 }
2229
2230 /**
2231  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2232  * @table: the sysctl table
2233  * @write: %TRUE if this is a write to the sysctl file
2234  * @filp: the file structure
2235  * @buffer: the user buffer
2236  * @lenp: the size of the user buffer
2237  * @ppos: pointer to the file position
2238  *
2239  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2240  * values from/to the user buffer, treated as an ASCII string.
2241  * The values read are assumed to be in 1/USER_HZ seconds, and
2242  * are converted into jiffies.
2243  *
2244  * Returns 0 on success.
2245  */
2246 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2247                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2248 {
2249     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2250                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2251 }
2252
2253 /**
2254  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2255  * @table: the sysctl table
2256  * @write: %TRUE if this is a write to the sysctl file
2257  * @filp: the file structure
2258  * @buffer: the user buffer
2259  * @lenp: the size of the user buffer
2260  * @ppos: file position
2261  * @ppos: the current position in the file
2262  *
2263  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2264  * values from/to the user buffer, treated as an ASCII string.
2265  * The values read are assumed to be in 1/1000 seconds, and
2266  * are converted into jiffies.
2267  *
2268  * Returns 0 on success.
2269  */
2270 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2271                              void __user *buffer, size_t *lenp, loff_t *ppos)
2272 {
2273         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2274                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2275 }
2276
2277 #else /* CONFIG_PROC_FS */
2278
2279 int proc_dostring(ctl_table *table, int write, struct file *filp,
2280                   void __user *buffer, size_t *lenp, loff_t *ppos)
2281 {
2282         return -ENOSYS;
2283 }
2284
2285 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
2286                             void __user *buffer, size_t *lenp, loff_t *ppos)
2287 {
2288         return -ENOSYS;
2289 }
2290
2291 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2292                   void __user *buffer, size_t *lenp, loff_t *ppos)
2293 {
2294         return -ENOSYS;
2295 }
2296
2297 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2298                         void __user *buffer, size_t *lenp, loff_t *ppos)
2299 {
2300         return -ENOSYS;
2301 }
2302
2303 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2304                     void __user *buffer, size_t *lenp, loff_t *ppos)
2305 {
2306         return -ENOSYS;
2307 }
2308
2309 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2310                     void __user *buffer, size_t *lenp, loff_t *ppos)
2311 {
2312         return -ENOSYS;
2313 }
2314
2315 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2316                     void __user *buffer, size_t *lenp, loff_t *ppos)
2317 {
2318         return -ENOSYS;
2319 }
2320
2321 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2322                              void __user *buffer, size_t *lenp, loff_t *ppos)
2323 {
2324         return -ENOSYS;
2325 }
2326
2327 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2328                     void __user *buffer, size_t *lenp, loff_t *ppos)
2329 {
2330         return -ENOSYS;
2331 }
2332
2333 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2334                                       struct file *filp,
2335                                       void __user *buffer,
2336                                       size_t *lenp, loff_t *ppos)
2337 {
2338     return -ENOSYS;
2339 }
2340
2341
2342 #endif /* CONFIG_PROC_FS */
2343
2344
2345 #ifdef CONFIG_SYSCTL_SYSCALL
2346 /*
2347  * General sysctl support routines
2348  */
2349
2350 /* The generic string strategy routine: */
2351 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2352                   void __user *oldval, size_t __user *oldlenp,
2353                   void __user *newval, size_t newlen, void **context)
2354 {
2355         if (!table->data || !table->maxlen)
2356                 return -ENOTDIR;
2357
2358         if (oldval && oldlenp) {
2359                 size_t bufsize;
2360                 if (get_user(bufsize, oldlenp))
2361                         return -EFAULT;
2362                 if (bufsize) {
2363                         size_t len = strlen(table->data), copied;
2364
2365                         /* This shouldn't trigger for a well-formed sysctl */
2366                         if (len > table->maxlen)
2367                                 len = table->maxlen;
2368
2369                         /* Copy up to a max of bufsize-1 bytes of the string */
2370                         copied = (len >= bufsize) ? bufsize - 1 : len;
2371
2372                         if (copy_to_user(oldval, table->data, copied) ||
2373                             put_user(0, (char __user *)(oldval + copied)))
2374                                 return -EFAULT;
2375                         if (put_user(len, oldlenp))
2376                                 return -EFAULT;
2377                 }
2378         }
2379         if (newval && newlen) {
2380                 size_t len = newlen;
2381                 if (len > table->maxlen)
2382                         len = table->maxlen;
2383                 if(copy_from_user(table->data, newval, len))
2384                         return -EFAULT;
2385                 if (len == table->maxlen)
2386                         len--;
2387                 ((char *) table->data)[len] = 0;
2388         }
2389         return 1;
2390 }
2391
2392 /*
2393  * This function makes sure that all of the integers in the vector
2394  * are between the minimum and maximum values given in the arrays
2395  * table->extra1 and table->extra2, respectively.
2396  */
2397 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2398                 void __user *oldval, size_t __user *oldlenp,
2399                 void __user *newval, size_t newlen, void **context)
2400 {
2401
2402         if (newval && newlen) {
2403                 int __user *vec = (int __user *) newval;
2404                 int *min = (int *) table->extra1;
2405                 int *max = (int *) table->extra2;
2406                 size_t length;
2407                 int i;
2408
2409                 if (newlen % sizeof(int) != 0)
2410                         return -EINVAL;
2411
2412                 if (!table->extra1 && !table->extra2)
2413                         return 0;
2414
2415                 if (newlen > table->maxlen)
2416                         newlen = table->maxlen;
2417                 length = newlen / sizeof(int);
2418
2419                 for (i = 0; i < length; i++) {
2420                         int value;
2421                         if (get_user(value, vec + i))
2422                                 return -EFAULT;
2423                         if (min && value < min[i])
2424                                 return -EINVAL;
2425                         if (max && value > max[i])
2426                                 return -EINVAL;
2427                 }
2428         }
2429         return 0;
2430 }
2431
2432 /* Strategy function to convert jiffies to seconds */
2433 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2434                 void __user *oldval, size_t __user *oldlenp,
2435                 void __user *newval, size_t newlen, void **context)
2436 {
2437         if (oldval) {
2438                 size_t olen;
2439                 if (oldlenp) {
2440                         if (get_user(olen, oldlenp))
2441                                 return -EFAULT;
2442                         if (olen!=sizeof(int))
2443                                 return -EINVAL;
2444                 }
2445                 if (put_user(*(int *)(table->data)/HZ, (int __user *)oldval) ||
2446                     (oldlenp && put_user(sizeof(int),oldlenp)))
2447                         return -EFAULT;
2448         }
2449         if (newval && newlen) {
2450                 int new;
2451                 if (newlen != sizeof(int))
2452                         return -EINVAL;
2453                 if (get_user(new, (int __user *)newval))
2454                         return -EFAULT;
2455                 *(int *)(table->data) = new*HZ;
2456         }
2457         return 1;
2458 }
2459
2460 /* Strategy function to convert jiffies to seconds */
2461 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2462                 void __user *oldval, size_t __user *oldlenp,
2463                 void __user *newval, size_t newlen, void **context)
2464 {
2465         if (oldval) {
2466                 size_t olen;
2467                 if (oldlenp) {
2468                         if (get_user(olen, oldlenp))
2469                                 return -EFAULT;
2470                         if (olen!=sizeof(int))
2471                                 return -EINVAL;
2472                 }
2473                 if (put_user(jiffies_to_msecs(*(int *)(table->data)), (int __user *)oldval) ||
2474                     (oldlenp && put_user(sizeof(int),oldlenp)))
2475                         return -EFAULT;
2476         }
2477         if (newval && newlen) {
2478                 int new;
2479                 if (newlen != sizeof(int))
2480                         return -EINVAL;
2481                 if (get_user(new, (int __user *)newval))
2482                         return -EFAULT;
2483                 *(int *)(table->data) = msecs_to_jiffies(new);
2484         }
2485         return 1;
2486 }
2487
2488 #else /* CONFIG_SYSCTL_SYSCALL */
2489
2490
2491 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2492 {
2493         static int msg_count;
2494
2495         if (msg_count < 5) {
2496                 msg_count++;
2497                 printk(KERN_INFO
2498                         "warning: process `%s' used the removed sysctl "
2499                         "system call\n", current->comm);
2500         }
2501         return -ENOSYS;
2502 }
2503
2504 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2505                   void __user *oldval, size_t __user *oldlenp,
2506                   void __user *newval, size_t newlen, void **context)
2507 {
2508         return -ENOSYS;
2509 }
2510
2511 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2512                 void __user *oldval, size_t __user *oldlenp,
2513                 void __user *newval, size_t newlen, void **context)
2514 {
2515         return -ENOSYS;
2516 }
2517
2518 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2519                 void __user *oldval, size_t __user *oldlenp,
2520                 void __user *newval, size_t newlen, void **context)
2521 {
2522         return -ENOSYS;
2523 }
2524
2525 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2526                 void __user *oldval, size_t __user *oldlenp,
2527                 void __user *newval, size_t newlen, void **context)
2528 {
2529         return -ENOSYS;
2530 }
2531
2532 #endif /* CONFIG_SYSCTL_SYSCALL */
2533
2534 /*
2535  * No sense putting this after each symbol definition, twice,
2536  * exception granted :-)
2537  */
2538 EXPORT_SYMBOL(proc_dointvec);
2539 EXPORT_SYMBOL(proc_dointvec_jiffies);
2540 EXPORT_SYMBOL(proc_dointvec_minmax);
2541 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2542 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2543 EXPORT_SYMBOL(proc_dostring);
2544 EXPORT_SYMBOL(proc_doulongvec_minmax);
2545 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2546 EXPORT_SYMBOL(register_sysctl_table);
2547 EXPORT_SYMBOL(sysctl_intvec);
2548 EXPORT_SYMBOL(sysctl_jiffies);
2549 EXPORT_SYMBOL(sysctl_ms_jiffies);
2550 EXPORT_SYMBOL(sysctl_string);
2551 EXPORT_SYMBOL(unregister_sysctl_table);