kernel/sysctl.c

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/config.h>
  22 #include <linux/module.h>
  23 #include <linux/mm.h>
  24 #include <linux/swap.h>
  25 #include <linux/slab.h>
  26 #include <linux/sysctl.h>
  27 #include <linux/proc_fs.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/sysrq.h>
  35 #include <linux/highuid.h>
  36 #include <linux/writeback.h>
  37 #include <linux/hugetlb.h>
  38 #include <linux/security.h>
  39 #include <linux/initrd.h>
  40 #include <linux/times.h>
  41 #include <linux/limits.h>
  42 #include <asm/uaccess.h>
  43
  44 #ifdef CONFIG_ROOT_NFS
  45 #include <linux/nfs_fs.h>
  46 #endif
  47
  48 #if defined(CONFIG_SYSCTL)
  49
  50 /* External variables not in a header file. */
  51 extern int panic_timeout;
  52 extern int C_A_D;
  53 extern int sysctl_overcommit_memory;
  54 extern int sysctl_overcommit_ratio;
  55 extern int max_threads;
  56 extern atomic_t nr_queued_signals;
  57 extern int max_queued_signals;
  58 extern int sysrq_enabled;
  59 extern int core_uses_pid;
  60 extern char core_pattern[];
  61 extern int cad_pid;
  62 extern int pid_max;
  63 extern int sysctl_lower_zone_protection;
  64 extern int min_free_kbytes;
  65 extern int printk_ratelimit_jiffies;
  66 extern int printk_ratelimit_burst;
  67
  68 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  69 static int maxolduid = 65535;
  70 static int minolduid;
  71
  72 static int ngroups_max = NGROUPS_MAX;
  73
  74 #ifdef CONFIG_KMOD
  75 extern char modprobe_path[];
  76 #endif
  77 #ifdef CONFIG_HOTPLUG
  78 extern char hotplug_path[];
  79 #endif
  80 #ifdef CONFIG_CHR_DEV_SG
  81 extern int sg_big_buff;
  82 #endif
  83 #ifdef CONFIG_SYSVIPC
  84 extern size_t shm_ctlmax;
  85 extern size_t shm_ctlall;
  86 extern int shm_ctlmni;
  87 extern int msg_ctlmax;
  88 extern int msg_ctlmnb;
  89 extern int msg_ctlmni;
  90 extern int sem_ctls[];
  91 #endif
  92
  93 #ifdef __sparc__
  94 extern char reboot_command [];
  95 extern int stop_a_enabled;
  96 extern int scons_pwroff;
  97 #endif
  98
  99 #ifdef __hppa__
 100 extern int pwrsw_enabled;
 101 extern int unaligned_enabled;
 102 #endif
 103
 104 #ifdef CONFIG_ARCH_S390
 105 #ifdef CONFIG_MATHEMU
 106 extern int sysctl_ieee_emulation_warnings;
 107 #endif
 108 extern int sysctl_userprocess_debug;
 109 #endif
 110
 111 extern int sysctl_hz_timer;
 112
 113 #if defined(CONFIG_PPC32) && defined(CONFIG_6xx)
 114 extern unsigned long powersave_nap;
 115 int proc_dol2crvec(ctl_table *table, int write, struct file *filp,
 116                   void *buffer, size_t *lenp);
 117 #endif
 118
 119 #ifdef CONFIG_BSD_PROCESS_ACCT
 120 extern int acct_parm[];
 121 #endif
 122
 123 static int parse_table(int __user *, int, void __user *, size_t __user *, void __user *, size_t,
 124                        ctl_table *, void **);
 125 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
 126                   void __user *buffer, size_t *lenp);
 127
 128 static ctl_table root_table[];
 129 static struct ctl_table_header root_table_header =
 130         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 131
 132 static ctl_table kern_table[];
 133 static ctl_table vm_table[];
 134 #ifdef CONFIG_NET
 135 extern ctl_table net_table[];
 136 #endif
 137 static ctl_table proc_table[];
 138 static ctl_table fs_table[];
 139 static ctl_table debug_table[];
 140 static ctl_table dev_table[];
 141 extern ctl_table random_table[];
 142 #ifdef CONFIG_UNIX98_PTYS
 143 extern ctl_table pty_table[];
 144 #endif
 145
 146 /* /proc declarations: */
 147
 148 #ifdef CONFIG_PROC_FS
 149
 150 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 151 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 152 static int proc_opensys(struct inode *, struct file *);
 153
 154 struct file_operations proc_sys_file_operations = {
 155         .open           = proc_opensys,
 156         .read           = proc_readsys,
 157         .write          = proc_writesys,
 158 };
 159
 160 extern struct proc_dir_entry *proc_sys_root;
 161
 162 static void register_proc_table(ctl_table *, struct proc_dir_entry *);
 163 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 164 #endif
 165
 166 /* The default sysctl tables: */
 167
 168 static ctl_table root_table[] = {
 169         {
 170                 .ctl_name       = CTL_KERN,
 171                 .procname       = "kernel",
 172                 .mode           = 0555,
 173                 .child          = kern_table,
 174         },
 175         {
 176                 .ctl_name       = CTL_VM,
 177                 .procname       = "vm",
 178                 .mode           = 0555,
 179                 .child          = vm_table,
 180         },
 181 #ifdef CONFIG_NET
 182         {
 183                 .ctl_name       = CTL_NET,
 184                 .procname       = "net",
 185                 .mode           = 0555,
 186                 .child          = net_table,
 187         },
 188 #endif
 189         {
 190                 .ctl_name       = CTL_PROC,
 191                 .procname       = "proc",
 192                 .mode           = 0555,
 193                 .child          = proc_table,
 194         },
 195         {
 196                 .ctl_name       = CTL_FS,
 197                 .procname       = "fs",
 198                 .mode           = 0555,
 199                 .child          = fs_table,
 200         },
 201         {
 202                 .ctl_name       = CTL_DEBUG,
 203                 .procname       = "debug",
 204                 .mode           = 0555,
 205                 .child          = debug_table,
 206         },
 207         {
 208                 .ctl_name       = CTL_DEV,
 209                 .procname       = "dev",
 210                 .mode           = 0555,
 211                 .child          = dev_table,
 212         },
 213         { .ctl_name = 0 }
 214 };
 215
 216 static ctl_table kern_table[] = {
 217         {
 218                 .ctl_name       = KERN_OSTYPE,
 219                 .procname       = "ostype",
 220                 .data           = system_utsname.sysname,
 221                 .maxlen         = 64,
 222                 .mode           = 0444,
 223                 .proc_handler   = &proc_doutsstring,
 224                 .strategy       = &sysctl_string,
 225         },
 226         {
 227                 .ctl_name       = KERN_OSRELEASE,
 228                 .procname       = "osrelease",
 229                 .data           = system_utsname.release,
 230                 .maxlen         = 64,
 231                 .mode           = 0444,
 232                 .proc_handler   = &proc_doutsstring,
 233                 .strategy       = &sysctl_string,
 234         },
 235         {
 236                 .ctl_name       = KERN_VERSION,
 237                 .procname       = "version",
 238                 .data           = system_utsname.version,
 239                 .maxlen         = 64,
 240                 .mode           = 0444,
 241                 .proc_handler   = &proc_doutsstring,
 242                 .strategy       = &sysctl_string,
 243         },
 244         {
 245                 .ctl_name       = KERN_NODENAME,
 246                 .procname       = "hostname",
 247                 .data           = system_utsname.nodename,
 248                 .maxlen         = 64,
 249                 .mode           = 0644,
 250                 .proc_handler   = &proc_doutsstring,
 251                 .strategy       = &sysctl_string,
 252         },
 253         {
 254                 .ctl_name       = KERN_DOMAINNAME,
 255                 .procname       = "domainname",
 256                 .data           = system_utsname.domainname,
 257                 .maxlen         = 64,
 258                 .mode           = 0644,
 259                 .proc_handler   = &proc_doutsstring,
 260                 .strategy       = &sysctl_string,
 261         },
 262         {
 263                 .ctl_name       = KERN_PANIC,
 264                 .procname       = "panic",
 265                 .data           = &panic_timeout,
 266                 .maxlen         = sizeof(int),
 267                 .mode           = 0644,
 268                 .proc_handler   = &proc_dointvec,
 269         },
 270         {
 271                 .ctl_name       = KERN_CORE_USES_PID,
 272                 .procname       = "core_uses_pid",
 273                 .data           = &core_uses_pid,
 274                 .maxlen         = sizeof(int),
 275                 .mode           = 0644,
 276                 .proc_handler   = &proc_dointvec,
 277         },
 278         {
 279                 .ctl_name       = KERN_CORE_PATTERN,
 280                 .procname       = "core_pattern",
 281                 .data           = core_pattern,
 282                 .maxlen         = 64,
 283                 .mode           = 0644,
 284                 .proc_handler   = &proc_dostring,
 285                 .strategy       = &sysctl_string,
 286         },
 287         {
 288                 .ctl_name       = KERN_TAINTED,
 289                 .procname       = "tainted",
 290                 .data           = &tainted,
 291                 .maxlen         = sizeof(int),
 292                 .mode           = 0644,
 293                 .proc_handler   = &proc_dointvec,
 294         },
 295         {
 296                 .ctl_name       = KERN_CAP_BSET,
 297                 .procname       = "cap-bound",
 298                 .data           = &cap_bset,
 299                 .maxlen         = sizeof(kernel_cap_t),
 300                 .mode           = 0600,
 301                 .proc_handler   = &proc_dointvec_bset,
 302         },
 303 #ifdef CONFIG_BLK_DEV_INITRD
 304         {
 305                 .ctl_name       = KERN_REALROOTDEV,
 306                 .procname       = "real-root-dev",
 307                 .data           = &real_root_dev,
 308                 .maxlen         = sizeof(int),
 309                 .mode           = 0644,
 310                 .proc_handler   = &proc_dointvec,
 311         },
 312 #endif
 313 #ifdef __sparc__
 314         {
 315                 .ctl_name       = KERN_SPARC_REBOOT,
 316                 .procname       = "reboot-cmd",
 317                 .data           = reboot_command,
 318                 .maxlen         = 256,
 319                 .mode           = 0644,
 320                 .proc_handler   = &proc_dostring,
 321                 .strategy       = &sysctl_string,
 322         },
 323         {
 324                 .ctl_name       = KERN_SPARC_STOP_A,
 325                 .procname       = "stop-a",
 326                 .data           = &stop_a_enabled,
 327                 .maxlen         = sizeof (int),
 328                 .mode           = 0644,
 329                 .proc_handler   = &proc_dointvec,
 330         },
 331         {
 332                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 333                 .procname       = "scons-poweroff",
 334                 .data           = &scons_pwroff,
 335                 .maxlen         = sizeof (int),
 336                 .mode           = 0644,
 337                 .proc_handler   = &proc_dointvec,
 338         },
 339 #endif
 340 #ifdef __hppa__
 341         {
 342                 .ctl_name       = KERN_HPPA_PWRSW,
 343                 .procname       = "soft-power",
 344                 .data           = &pwrsw_enabled,
 345                 .maxlen         = sizeof (int),
 346                 .mode           = 0644,
 347                 .proc_handler   = &proc_dointvec,
 348         },
 349         {
 350                 .ctl_name       = KERN_HPPA_UNALIGNED,
 351                 .procname       = "unaligned-trap",
 352                 .data           = &unaligned_enabled,
 353                 .maxlen         = sizeof (int),
 354                 .mode           = 0644,
 355                 .proc_handler   = &proc_dointvec,
 356         },
 357 #endif
 358 #if defined(CONFIG_PPC32) && defined(CONFIG_6xx)
 359         {
 360                 .ctl_name       = KERN_PPC_POWERSAVE_NAP,
 361                 .procname       = "powersave-nap",
 362                 .data           = &powersave_nap,
 363                 .maxlen         = sizeof(int),
 364                 .mode           = 0644,
 365                 .proc_handler   = &proc_dointvec,
 366         },
 367         {
 368                 .ctl_name       = KERN_PPC_L2CR,
 369                 .procname       = "l2cr",
 370                 .mode           = 0644,
 371                 .proc_handler   = &proc_dol2crvec,
 372         },
 373 #endif
 374         {
 375                 .ctl_name       = KERN_CTLALTDEL,
 376                 .procname       = "ctrl-alt-del",
 377                 .data           = &C_A_D,
 378                 .maxlen         = sizeof(int),
 379                 .mode           = 0644,
 380                 .proc_handler   = &proc_dointvec,
 381         },
 382         {
 383                 .ctl_name       = KERN_PRINTK,
 384                 .procname       = "printk",
 385                 .data           = &console_loglevel,
 386                 .maxlen         = 4*sizeof(int),
 387                 .mode           = 0644,
 388                 .proc_handler   = &proc_dointvec,
 389         },
 390 #ifdef CONFIG_KMOD
 391         {
 392                 .ctl_name       = KERN_MODPROBE,
 393                 .procname       = "modprobe",
 394                 .data           = &modprobe_path,
 395                 .maxlen         = 256,
 396                 .mode           = 0644,
 397                 .proc_handler   = &proc_dostring,
 398                 .strategy       = &sysctl_string,
 399         },
 400 #endif
 401 #ifdef CONFIG_HOTPLUG
 402         {
 403                 .ctl_name       = KERN_HOTPLUG,
 404                 .procname       = "hotplug",
 405                 .data           = &hotplug_path,
 406                 .maxlen         = 256,
 407                 .mode           = 0644,
 408                 .proc_handler   = &proc_dostring,
 409                 .strategy       = &sysctl_string,
 410         },
 411 #endif
 412 #ifdef CONFIG_CHR_DEV_SG
 413         {
 414                 .ctl_name       = KERN_SG_BIG_BUFF,
 415                 .procname       = "sg-big-buff",
 416                 .data           = &sg_big_buff,
 417                 .maxlen         = sizeof (int),
 418                 .mode           = 0444,
 419                 .proc_handler   = &proc_dointvec,
 420         },
 421 #endif
 422 #ifdef CONFIG_BSD_PROCESS_ACCT
 423         {
 424                 .ctl_name       = KERN_ACCT,
 425                 .procname       = "acct",
 426                 .data           = &acct_parm,
 427                 .maxlen         = 3*sizeof(int),
 428                 .mode           = 0644,
 429                 .proc_handler   = &proc_dointvec,
 430         },
 431 #endif
 432         {
 433                 .ctl_name       = KERN_RTSIGNR,
 434                 .procname       = "rtsig-nr",
 435                 .data           = &nr_queued_signals,
 436                 .maxlen         = sizeof(int),
 437                 .mode           = 0444,
 438                 .proc_handler   = &proc_dointvec,
 439         },
 440         {
 441                 .ctl_name       = KERN_RTSIGMAX,
 442                 .procname       = "rtsig-max",
 443                 .data           = &max_queued_signals,
 444                 .maxlen         = sizeof(int),
 445                 .mode           = 0644,
 446                 .proc_handler   = &proc_dointvec,
 447         },
 448 #ifdef CONFIG_SYSVIPC
 449         {
 450                 .ctl_name       = KERN_SHMMAX,
 451                 .procname       = "shmmax",
 452                 .data           = &shm_ctlmax,
 453                 .maxlen         = sizeof (size_t),
 454                 .mode           = 0644,
 455                 .proc_handler   = &proc_doulongvec_minmax,
 456         },
 457         {
 458                 .ctl_name       = KERN_SHMALL,
 459                 .procname       = "shmall",
 460                 .data           = &shm_ctlall,
 461                 .maxlen         = sizeof (size_t),
 462                 .mode           = 0644,
 463                 .proc_handler   = &proc_doulongvec_minmax,
 464         },
 465         {
 466                 .ctl_name       = KERN_SHMMNI,
 467                 .procname       = "shmmni",
 468                 .data           = &shm_ctlmni,
 469                 .maxlen         = sizeof (int),
 470                 .mode           = 0644,
 471                 .proc_handler   = &proc_dointvec,
 472         },
 473         {
 474                 .ctl_name       = KERN_MSGMAX,
 475                 .procname       = "msgmax",
 476                 .data           = &msg_ctlmax,
 477                 .maxlen         = sizeof (int),
 478                 .mode           = 0644,
 479                 .proc_handler   = &proc_dointvec,
 480         },
 481         {
 482                 .ctl_name       = KERN_MSGMNI,
 483                 .procname       = "msgmni",
 484                 .data           = &msg_ctlmni,
 485                 .maxlen         = sizeof (int),
 486                 .mode           = 0644,
 487                 .proc_handler   = &proc_dointvec,
 488         },
 489         {
 490                 .ctl_name       = KERN_MSGMNB,
 491                 .procname       =  "msgmnb",
 492                 .data           = &msg_ctlmnb,
 493                 .maxlen         = sizeof (int),
 494                 .mode           = 0644,
 495                 .proc_handler   = &proc_dointvec,
 496         },
 497         {
 498                 .ctl_name       = KERN_SEM,
 499                 .procname       = "sem",
 500                 .data           = &sem_ctls,
 501                 .maxlen         = 4*sizeof (int),
 502                 .mode           = 0644,
 503                 .proc_handler   = &proc_dointvec,
 504         },
 505 #endif
 506 #ifdef CONFIG_MAGIC_SYSRQ
 507         {
 508                 .ctl_name       = KERN_SYSRQ,
 509                 .procname       = "sysrq",
 510                 .data           = &sysrq_enabled,
 511                 .maxlen         = sizeof (int),
 512                 .mode           = 0644,
 513                 .proc_handler   = &proc_dointvec,
 514         },
 515 #endif
 516         {
 517                 .ctl_name       = KERN_CADPID,
 518                 .procname       = "cad_pid",
 519                 .data           = &cad_pid,
 520                 .maxlen         = sizeof (int),
 521                 .mode           = 0600,
 522                 .proc_handler   = &proc_dointvec,
 523         },
 524         {
 525                 .ctl_name       = KERN_MAX_THREADS,
 526                 .procname       = "threads-max",
 527                 .data           = &max_threads,
 528                 .maxlen         = sizeof(int),
 529                 .mode           = 0644,
 530                 .proc_handler   = &proc_dointvec,
 531         },
 532         {
 533                 .ctl_name       = KERN_RANDOM,
 534                 .procname       = "random",
 535                 .mode           = 0555,
 536                 .child          = random_table,
 537         },
 538 #ifdef CONFIG_UNIX98_PTYS
 539         {
 540                 .ctl_name       = KERN_PTY,
 541                 .procname       = "pty",
 542                 .mode           = 0555,
 543                 .child          = pty_table,
 544         },
 545 #endif
 546         {
 547                 .ctl_name       = KERN_OVERFLOWUID,
 548                 .procname       = "overflowuid",
 549                 .data           = &overflowuid,
 550                 .maxlen         = sizeof(int),
 551                 .mode           = 0644,
 552                 .proc_handler   = &proc_dointvec_minmax,
 553                 .strategy       = &sysctl_intvec,
 554                 .extra1         = &minolduid,
 555                 .extra2         = &maxolduid,
 556         },
 557         {
 558                 .ctl_name       = KERN_OVERFLOWGID,
 559                 .procname       = "overflowgid",
 560                 .data           = &overflowgid,
 561                 .maxlen         = sizeof(int),
 562                 .mode           = 0644,
 563                 .proc_handler   = &proc_dointvec_minmax,
 564                 .strategy       = &sysctl_intvec,
 565                 .extra1         = &minolduid,
 566                 .extra2         = &maxolduid,
 567         },
 568 #ifdef CONFIG_ARCH_S390
 569 #ifdef CONFIG_MATHEMU
 570         {
 571                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 572                 .procname       = "ieee_emulation_warnings",
 573                 .data           = &sysctl_ieee_emulation_warnings,
 574                 .maxlen         = sizeof(int),
 575                 .mode           = 0644,
 576                 .proc_handler   = &proc_dointvec,
 577         },
 578 #endif
 579 #ifdef CONFIG_NO_IDLE_HZ
 580         {
 581                 .ctl_name       = KERN_HZ_TIMER,
 582                 .procname       = "hz_timer",
 583                 .data           = &sysctl_hz_timer,
 584                 .maxlen         = sizeof(int),
 585                 .mode           = 0644,
 586                 .proc_handler   = &proc_dointvec,
 587         },
 588 #endif
 589         {
 590                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 591                 .procname       = "userprocess_debug",
 592                 .data           = &sysctl_userprocess_debug,
 593                 .maxlen         = sizeof(int),
 594                 .mode           = 0644,
 595                 .proc_handler   = &proc_dointvec,
 596         },
 597 #endif
 598         {
 599                 .ctl_name       = KERN_PIDMAX,
 600                 .procname       = "pid_max",
 601                 .data           = &pid_max,
 602                 .maxlen         = sizeof (int),
 603                 .mode           = 0644,
 604                 .proc_handler   = &proc_dointvec,
 605         },
 606         {
 607                 .ctl_name       = KERN_PANIC_ON_OOPS,
 608                 .procname       = "panic_on_oops",
 609                 .data           = &panic_on_oops,
 610                 .maxlen         = sizeof(int),
 611                 .mode           = 0644,
 612                 .proc_handler   = &proc_dointvec,
 613         },
 614         {
 615                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 616                 .procname       = "printk_ratelimit",
 617                 .data           = &printk_ratelimit_jiffies,
 618                 .maxlen         = sizeof(int),
 619                 .mode           = 0644,
 620                 .proc_handler   = &proc_dointvec_jiffies,
 621                 .strategy       = &sysctl_jiffies,
 622         },
 623         {
 624                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 625                 .procname       = "printk_ratelimit_burst",
 626                 .data           = &printk_ratelimit_burst,
 627                 .maxlen         = sizeof(int),
 628                 .mode           = 0644,
 629                 .proc_handler   = &proc_dointvec,
 630         },
 631         {
 632                 .ctl_name       = KERN_NGROUPS_MAX,
 633                 .procname       = "ngroups_max",
 634                 .data           = &ngroups_max,
 635                 .maxlen         = sizeof (int),
 636                 .mode           = 0444,
 637                 .proc_handler   = &proc_dointvec,
 638         },
 639         { .ctl_name = 0 }
 640 };
 641
 642 /* Constants for minimum and maximum testing in vm_table.
 643    We use these as one-element integer vectors. */
 644 static int zero;
 645 static int one_hundred = 100;
 646
 647
 648 static ctl_table vm_table[] = {
 649         {
 650                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 651                 .procname       = "overcommit_memory",
 652                 .data           = &sysctl_overcommit_memory,
 653                 .maxlen         = sizeof(sysctl_overcommit_memory),
 654                 .mode           = 0644,
 655                 .proc_handler   = &proc_dointvec,
 656         },
 657         {
 658                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 659                 .procname       = "overcommit_ratio",
 660                 .data           = &sysctl_overcommit_ratio,
 661                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 662                 .mode           = 0644,
 663                 .proc_handler   = &proc_dointvec,
 664         },
 665         {
 666                 .ctl_name       = VM_PAGE_CLUSTER,
 667                 .procname       = "page-cluster",
 668                 .data           = &page_cluster,
 669                 .maxlen         = sizeof(int),
 670                 .mode           = 0644,
 671                 .proc_handler   = &proc_dointvec,
 672         },
 673         {
 674                 .ctl_name       = VM_DIRTY_BACKGROUND,
 675                 .procname       = "dirty_background_ratio",
 676                 .data           = &dirty_background_ratio,
 677                 .maxlen         = sizeof(dirty_background_ratio),
 678                 .mode           = 0644,
 679                 .proc_handler   = &proc_dointvec_minmax,
 680                 .strategy       = &sysctl_intvec,
 681                 .extra1         = &zero,
 682                 .extra2         = &one_hundred,
 683         },
 684         {
 685                 .ctl_name       = VM_DIRTY_RATIO,
 686                 .procname       = "dirty_ratio",
 687                 .data           = &vm_dirty_ratio,
 688                 .maxlen         = sizeof(vm_dirty_ratio),
 689                 .mode           = 0644,
 690                 .proc_handler   = &proc_dointvec_minmax,
 691                 .strategy       = &sysctl_intvec,
 692                 .extra1         = &zero,
 693                 .extra2         = &one_hundred,
 694         },
 695         {
 696                 .ctl_name       = VM_DIRTY_WB_CS,
 697                 .procname       = "dirty_writeback_centisecs",
 698                 .data           = &dirty_writeback_centisecs,
 699                 .maxlen         = sizeof(dirty_writeback_centisecs),
 700                 .mode           = 0644,
 701                 .proc_handler   = &dirty_writeback_centisecs_handler,
 702         },
 703         {
 704                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 705                 .procname       = "dirty_expire_centisecs",
 706                 .data           = &dirty_expire_centisecs,
 707                 .maxlen         = sizeof(dirty_expire_centisecs),
 708                 .mode           = 0644,
 709                 .proc_handler   = &proc_dointvec,
 710         },
 711         {
 712                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 713                 .procname       = "nr_pdflush_threads",
 714                 .data           = &nr_pdflush_threads,
 715                 .maxlen         = sizeof nr_pdflush_threads,
 716                 .mode           = 0444 /* read-only*/,
 717                 .proc_handler   = &proc_dointvec,
 718         },
 719         {
 720                 .ctl_name       = VM_SWAPPINESS,
 721                 .procname       = "swappiness",
 722                 .data           = &vm_swappiness,
 723                 .maxlen         = sizeof(vm_swappiness),
 724                 .mode           = 0644,
 725                 .proc_handler   = &proc_dointvec_minmax,
 726                 .strategy       = &sysctl_intvec,
 727                 .extra1         = &zero,
 728                 .extra2         = &one_hundred,
 729         },
 730 #ifdef CONFIG_HUGETLB_PAGE
 731          {
 732                 .ctl_name       = VM_HUGETLB_PAGES,
 733                 .procname       = "nr_hugepages",
 734                 .data           = &max_huge_pages,
 735                 .maxlen         = sizeof(unsigned long),
 736                 .mode           = 0644,
 737                 .proc_handler   = &hugetlb_sysctl_handler,
 738                 .extra1         = (void *)&hugetlb_zero,
 739                 .extra2         = (void *)&hugetlb_infinity,
 740          },
 741 #endif
 742         {
 743                 .ctl_name       = VM_LOWER_ZONE_PROTECTION,
 744                 .procname       = "lower_zone_protection",
 745                 .data           = &sysctl_lower_zone_protection,
 746                 .maxlen         = sizeof(sysctl_lower_zone_protection),
 747                 .mode           = 0644,
 748                 .proc_handler   = &lower_zone_protection_sysctl_handler,
 749                 .strategy       = &sysctl_intvec,
 750                 .extra1         = &zero,
 751         },
 752         {
 753                 .ctl_name       = VM_MIN_FREE_KBYTES,
 754                 .procname       = "min_free_kbytes",
 755                 .data           = &min_free_kbytes,
 756                 .maxlen         = sizeof(min_free_kbytes),
 757                 .mode           = 0644,
 758                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 759                 .strategy       = &sysctl_intvec,
 760                 .extra1         = &zero,
 761         },
 762         {
 763                 .ctl_name       = VM_MAX_MAP_COUNT,
 764                 .procname       = "max_map_count",
 765                 .data           = &sysctl_max_map_count,
 766                 .maxlen         = sizeof(sysctl_max_map_count),
 767                 .mode           = 0644,
 768                 .proc_handler   = &proc_dointvec
 769         },
 770         {
 771                 .ctl_name       = VM_LAPTOP_MODE,
 772                 .procname       = "laptop_mode",
 773                 .data           = &laptop_mode,
 774                 .maxlen         = sizeof(laptop_mode),
 775                 .mode           = 0644,
 776                 .proc_handler   = &proc_dointvec,
 777                 .strategy       = &sysctl_intvec,
 778                 .extra1         = &zero,
 779         },
 780         {
 781                 .ctl_name       = VM_BLOCK_DUMP,
 782                 .procname       = "block_dump",
 783                 .data           = &block_dump,
 784                 .maxlen         = sizeof(block_dump),
 785                 .mode           = 0644,
 786                 .proc_handler   = &proc_dointvec,
 787                 .strategy       = &sysctl_intvec,
 788                 .extra1         = &zero,
 789         },
 790         { .ctl_name = 0 }
 791 };
 792
 793 static ctl_table proc_table[] = {
 794         { .ctl_name = 0 }
 795 };
 796
 797 static ctl_table fs_table[] = {
 798         {
 799                 .ctl_name       = FS_NRINODE,
 800                 .procname       = "inode-nr",
 801                 .data           = &inodes_stat,
 802                 .maxlen         = 2*sizeof(int),
 803                 .mode           = 0444,
 804                 .proc_handler   = &proc_dointvec,
 805         },
 806         {
 807                 .ctl_name       = FS_STATINODE,
 808                 .procname       = "inode-state",
 809                 .data           = &inodes_stat,
 810                 .maxlen         = 7*sizeof(int),
 811                 .mode           = 0444,
 812                 .proc_handler   = &proc_dointvec,
 813         },
 814         {
 815                 .ctl_name       = FS_NRFILE,
 816                 .procname       = "file-nr",
 817                 .data           = &files_stat,
 818                 .maxlen         = 3*sizeof(int),
 819                 .mode           = 0444,
 820                 .proc_handler   = &proc_dointvec,
 821         },
 822         {
 823                 .ctl_name       = FS_MAXFILE,
 824                 .procname       = "file-max",
 825                 .data           = &files_stat.max_files,
 826                 .maxlen         = sizeof(int),
 827                 .mode           = 0644,
 828                 .proc_handler   = &proc_dointvec,
 829         },
 830         {
 831                 .ctl_name       = FS_DENTRY,
 832                 .procname       = "dentry-state",
 833                 .data           = &dentry_stat,
 834                 .maxlen         = 6*sizeof(int),
 835                 .mode           = 0444,
 836                 .proc_handler   = &proc_dointvec,
 837         },
 838         {
 839                 .ctl_name       = FS_OVERFLOWUID,
 840                 .procname       = "overflowuid",
 841                 .data           = &fs_overflowuid,
 842                 .maxlen         = sizeof(int),
 843                 .mode           = 0644,
 844                 .proc_handler   = &proc_dointvec_minmax,
 845                 .strategy       = &sysctl_intvec,
 846                 .extra1         = &minolduid,
 847                 .extra2         = &maxolduid,
 848         },
 849         {
 850                 .ctl_name       = FS_OVERFLOWGID,
 851                 .procname       = "overflowgid",
 852                 .data           = &fs_overflowgid,
 853                 .maxlen         = sizeof(int),
 854                 .mode           = 0644,
 855                 .proc_handler   = &proc_dointvec_minmax,
 856                 .strategy       = &sysctl_intvec,
 857                 .extra1         = &minolduid,
 858                 .extra2         = &maxolduid,
 859         },
 860         {
 861                 .ctl_name       = FS_LEASES,
 862                 .procname       = "leases-enable",
 863                 .data           = &leases_enable,
 864                 .maxlen         = sizeof(int),
 865                 .mode           = 0644,
 866                 .proc_handler   = &proc_dointvec,
 867         },
 868         {
 869                 .ctl_name       = FS_DIR_NOTIFY,
 870                 .procname       = "dir-notify-enable",
 871                 .data           = &dir_notify_enable,
 872                 .maxlen         = sizeof(int),
 873                 .mode           = 0644,
 874                 .proc_handler   = &proc_dointvec,
 875         },
 876         {
 877                 .ctl_name       = FS_LEASE_TIME,
 878                 .procname       = "lease-break-time",
 879                 .data           = &lease_break_time,
 880                 .maxlen         = sizeof(int),
 881                 .mode           = 0644,
 882                 .proc_handler   = &proc_dointvec,
 883         },
 884         {
 885                 .ctl_name       = FS_AIO_NR,
 886                 .procname       = "aio-nr",
 887                 .data           = &aio_nr,
 888                 .maxlen         = sizeof(aio_nr),
 889                 .mode           = 0444,
 890                 .proc_handler   = &proc_dointvec,
 891         },
 892         {
 893                 .ctl_name       = FS_AIO_MAX_NR,
 894                 .procname       = "aio-max-nr",
 895                 .data           = &aio_max_nr,
 896                 .maxlen         = sizeof(aio_max_nr),
 897                 .mode           = 0644,
 898                 .proc_handler   = &proc_dointvec,
 899         },
 900         { .ctl_name = 0 }
 901 };
 902
 903 static ctl_table debug_table[] = {
 904         { .ctl_name = 0 }
 905 };
 906
 907 static ctl_table dev_table[] = {
 908         { .ctl_name = 0 }
 909 };
 910
 911 extern void init_irq_proc (void);
 912
 913 void __init sysctl_init(void)
 914 {
 915 #ifdef CONFIG_PROC_FS
 916         register_proc_table(root_table, proc_sys_root);
 917         init_irq_proc();
 918 #endif
 919 }
 920
 921 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
 922                void __user *newval, size_t newlen)
 923 {
 924         struct list_head *tmp;
 925
 926         if (nlen <= 0 || nlen >= CTL_MAXNAME)
 927                 return -ENOTDIR;
 928         if (oldval) {
 929                 int old_len;
 930                 if (!oldlenp || get_user(old_len, oldlenp))
 931                         return -EFAULT;
 932         }
 933         tmp = &root_table_header.ctl_entry;
 934         do {
 935                 struct ctl_table_header *head =
 936                         list_entry(tmp, struct ctl_table_header, ctl_entry);
 937                 void *context = NULL;
 938                 int error = parse_table(name, nlen, oldval, oldlenp,
 939                                         newval, newlen, head->ctl_table,
 940                                         &context);
 941                 if (context)
 942                         kfree(context);
 943                 if (error != -ENOTDIR)
 944                         return error;
 945                 tmp = tmp->next;
 946         } while (tmp != &root_table_header.ctl_entry);
 947         return -ENOTDIR;
 948 }
 949
 950 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
 951 {
 952         struct __sysctl_args tmp;
 953         int error;
 954
 955         if (copy_from_user(&tmp, args, sizeof(tmp)))
 956                 return -EFAULT;
 957
 958         lock_kernel();
 959         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
 960                           tmp.newval, tmp.newlen);
 961         unlock_kernel();
 962         return error;
 963 }
 964
 965 /*
 966  * ctl_perm does NOT grant the superuser all rights automatically, because
 967  * some sysctl variables are readonly even to root.
 968  */
 969
 970 static int test_perm(int mode, int op)
 971 {
 972         if (!current->euid)
 973                 mode >>= 6;
 974         else if (in_egroup_p(0))
 975                 mode >>= 3;
 976         if ((mode & op & 0007) == op)
 977                 return 0;
 978         return -EACCES;
 979 }
 980
 981 static inline int ctl_perm(ctl_table *table, int op)
 982 {
 983         int error;
 984         error = security_sysctl(table, op);
 985         if (error)
 986                 return error;
 987         return test_perm(table->mode, op);
 988 }
 989
 990 static int parse_table(int __user *name, int nlen,
 991                        void __user *oldval, size_t __user *oldlenp,
 992                        void __user *newval, size_t newlen,
 993                        ctl_table *table, void **context)
 994 {
 995         int n;
 996 repeat:
 997         if (!nlen)
 998                 return -ENOTDIR;
 999         if (get_user(n, name))
1000                 return -EFAULT;
1001         for ( ; table->ctl_name; table++) {
1002                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1003                         int error;
1004                         if (table->child) {
1005                                 if (ctl_perm(table, 001))
1006                                         return -EPERM;
1007                                 if (table->strategy) {
1008                                         error = table->strategy(
1009                                                 table, name, nlen,
1010                                                 oldval, oldlenp,
1011                                                 newval, newlen, context);
1012                                         if (error)
1013                                                 return error;
1014                                 }
1015                                 name++;
1016                                 nlen--;
1017                                 table = table->child;
1018                                 goto repeat;
1019                         }
1020                         error = do_sysctl_strategy(table, name, nlen,
1021                                                    oldval, oldlenp,
1022                                                    newval, newlen, context);
1023                         return error;
1024                 }
1025         }
1026         return -ENOTDIR;
1027 }
1028
1029 /* Perform the actual read/write of a sysctl table entry. */
1030 int do_sysctl_strategy (ctl_table *table,
1031                         int __user *name, int nlen,
1032                         void __user *oldval, size_t __user *oldlenp,
1033                         void __user *newval, size_t newlen, void **context)
1034 {
1035         int op = 0, rc;
1036         size_t len;
1037
1038         if (oldval)
1039                 op |= 004;
1040         if (newval)
1041                 op |= 002;
1042         if (ctl_perm(table, op))
1043                 return -EPERM;
1044
1045         if (table->strategy) {
1046                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1047                                      newval, newlen, context);
1048                 if (rc < 0)
1049                         return rc;
1050                 if (rc > 0)
1051                         return 0;
1052         }
1053
1054         /* If there is no strategy routine, or if the strategy returns
1055          * zero, proceed with automatic r/w */
1056         if (table->data && table->maxlen) {
1057                 if (oldval && oldlenp) {
1058                         if (get_user(len, oldlenp))
1059                                 return -EFAULT;
1060                         if (len) {
1061                                 if (len > table->maxlen)
1062                                         len = table->maxlen;
1063                                 if(copy_to_user(oldval, table->data, len))
1064                                         return -EFAULT;
1065                                 if(put_user(len, oldlenp))
1066                                         return -EFAULT;
1067                         }
1068                 }
1069                 if (newval && newlen) {
1070                         len = newlen;
1071                         if (len > table->maxlen)
1072                                 len = table->maxlen;
1073                         if(copy_from_user(table->data, newval, len))
1074                                 return -EFAULT;
1075                 }
1076         }
1077         return 0;
1078 }
1079
1080 /**
1081  * register_sysctl_table - register a sysctl hierarchy
1082  * @table: the top-level table structure
1083  * @insert_at_head: whether the entry should be inserted in front or at the end
1084  *
1085  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1086  * array. An entry with a ctl_name of 0 terminates the table.
1087  *
1088  * The members of the &ctl_table structure are used as follows:
1089  *
1090  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1091  *            must be unique within that level of sysctl
1092  *
1093  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1094  *            enter a sysctl file
1095  *
1096  * data - a pointer to data for use by proc_handler
1097  *
1098  * maxlen - the maximum size in bytes of the data
1099  *
1100  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1101  *
1102  * child - a pointer to the child sysctl table if this entry is a directory, or
1103  *         %NULL.
1104  *
1105  * proc_handler - the text handler routine (described below)
1106  *
1107  * strategy - the strategy routine (described below)
1108  *
1109  * de - for internal use by the sysctl routines
1110  *
1111  * extra1, extra2 - extra pointers usable by the proc handler routines
1112  *
1113  * Leaf nodes in the sysctl tree will be represented by a single file
1114  * under /proc; non-leaf nodes will be represented by directories.
1115  *
1116  * sysctl(2) can automatically manage read and write requests through
1117  * the sysctl table.  The data and maxlen fields of the ctl_table
1118  * struct enable minimal validation of the values being written to be
1119  * performed, and the mode field allows minimal authentication.
1120  *
1121  * More sophisticated management can be enabled by the provision of a
1122  * strategy routine with the table entry.  This will be called before
1123  * any automatic read or write of the data is performed.
1124  *
1125  * The strategy routine may return
1126  *
1127  * < 0 - Error occurred (error is passed to user process)
1128  *
1129  * 0   - OK - proceed with automatic read or write.
1130  *
1131  * > 0 - OK - read or write has been done by the strategy routine, so
1132  *       return immediately.
1133  *
1134  * There must be a proc_handler routine for any terminal nodes
1135  * mirrored under /proc/sys (non-terminals are handled by a built-in
1136  * directory handler).  Several default handlers are available to
1137  * cover common cases -
1138  *
1139  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1140  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1141  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1142  *
1143  * It is the handler's job to read the input buffer from user memory
1144  * and process it. The handler should return 0 on success.
1145  *
1146  * This routine returns %NULL on a failure to register, and a pointer
1147  * to the table header on success.
1148  */
1149 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1150                                                int insert_at_head)
1151 {
1152         struct ctl_table_header *tmp;
1153         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1154         if (!tmp)
1155                 return NULL;
1156         tmp->ctl_table = table;
1157         INIT_LIST_HEAD(&tmp->ctl_entry);
1158         if (insert_at_head)
1159                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1160         else
1161                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1162 #ifdef CONFIG_PROC_FS
1163         register_proc_table(table, proc_sys_root);
1164 #endif
1165         return tmp;
1166 }
1167
1168 /**
1169  * unregister_sysctl_table - unregister a sysctl table hierarchy
1170  * @header: the header returned from register_sysctl_table
1171  *
1172  * Unregisters the sysctl table and all children. proc entries may not
1173  * actually be removed until they are no longer used by anyone.
1174  */
1175 void unregister_sysctl_table(struct ctl_table_header * header)
1176 {
1177         list_del(&header->ctl_entry);
1178 #ifdef CONFIG_PROC_FS
1179         unregister_proc_table(header->ctl_table, proc_sys_root);
1180 #endif
1181         kfree(header);
1182 }
1183
1184 /*
1185  * /proc/sys support
1186  */
1187
1188 #ifdef CONFIG_PROC_FS
1189
1190 /* Scan the sysctl entries in table and add them all into /proc */
1191 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root)
1192 {
1193         struct proc_dir_entry *de;
1194         int len;
1195         mode_t mode;
1196
1197         for (; table->ctl_name; table++) {
1198                 /* Can't do anything without a proc name. */
1199                 if (!table->procname)
1200                         continue;
1201                 /* Maybe we can't do anything with it... */
1202                 if (!table->proc_handler && !table->child) {
1203                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1204                                 table->procname);
1205                         continue;
1206                 }
1207
1208                 len = strlen(table->procname);
1209                 mode = table->mode;
1210
1211                 de = NULL;
1212                 if (table->proc_handler)
1213                         mode |= S_IFREG;
1214                 else {
1215                         mode |= S_IFDIR;
1216                         for (de = root->subdir; de; de = de->next) {
1217                                 if (proc_match(len, table->procname, de))
1218                                         break;
1219                         }
1220                         /* If the subdir exists already, de is non-NULL */
1221                 }
1222
1223                 if (!de) {
1224                         de = create_proc_entry(table->procname, mode, root);
1225                         if (!de)
1226                                 continue;
1227                         de->data = (void *) table;
1228                         if (table->proc_handler)
1229                                 de->proc_fops = &proc_sys_file_operations;
1230                 }
1231                 table->de = de;
1232                 if (de->mode & S_IFDIR)
1233                         register_proc_table(table->child, de);
1234         }
1235 }
1236
1237 /*
1238  * Unregister a /proc sysctl table and any subdirectories.
1239  */
1240 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1241 {
1242         struct proc_dir_entry *de;
1243         for (; table->ctl_name; table++) {
1244                 if (!(de = table->de))
1245                         continue;
1246                 if (de->mode & S_IFDIR) {
1247                         if (!table->child) {
1248                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1249                                 continue;
1250                         }
1251                         unregister_proc_table(table->child, de);
1252
1253                         /* Don't unregister directories which still have entries.. */
1254                         if (de->subdir)
1255                                 continue;
1256                 }
1257
1258                 /* Don't unregister proc entries that are still being used.. */
1259                 if (atomic_read(&de->count))
1260                         continue;
1261
1262                 table->de = NULL;
1263                 remove_proc_entry(table->procname, root);
1264         }
1265 }
1266
1267 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1268                           size_t count, loff_t *ppos)
1269 {
1270         int op;
1271         struct proc_dir_entry *de;
1272         struct ctl_table *table;
1273         size_t res;
1274         ssize_t error;
1275
1276         de = PDE(file->f_dentry->d_inode);
1277         if (!de || !de->data)
1278                 return -ENOTDIR;
1279         table = (struct ctl_table *) de->data;
1280         if (!table || !table->proc_handler)
1281                 return -ENOTDIR;
1282         op = (write ? 002 : 004);
1283         if (ctl_perm(table, op))
1284                 return -EPERM;
1285
1286         res = count;
1287
1288         /*
1289          * FIXME: we need to pass on ppos to the handler.
1290          */
1291
1292         error = (*table->proc_handler) (table, write, file, buf, &res);
1293         if (error)
1294                 return error;
1295         return res;
1296 }
1297
1298 static int proc_opensys(struct inode *inode, struct file *file)
1299 {
1300         if (file->f_mode & FMODE_WRITE) {
1301                 /*
1302                  * sysctl entries that are not writable,
1303                  * are _NOT_ writable, capabilities or not.
1304                  */
1305                 if (!(inode->i_mode & S_IWUSR))
1306                         return -EPERM;
1307         }
1308
1309         return 0;
1310 }
1311
1312 static ssize_t proc_readsys(struct file * file, char __user * buf,
1313                             size_t count, loff_t *ppos)
1314 {
1315         return do_rw_proc(0, file, buf, count, ppos);
1316 }
1317
1318 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1319                              size_t count, loff_t *ppos)
1320 {
1321         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1322 }
1323
1324 /**
1325  * proc_dostring - read a string sysctl
1326  * @table: the sysctl table
1327  * @write: %TRUE if this is a write to the sysctl file
1328  * @filp: the file structure
1329  * @buffer: the user buffer
1330  * @lenp: the size of the user buffer
1331  *
1332  * Reads/writes a string from/to the user buffer. If the kernel
1333  * buffer provided is not large enough to hold the string, the
1334  * string is truncated. The copied string is %NULL-terminated.
1335  * If the string is being read by the user process, it is copied
1336  * and a newline '\n' is added. It is truncated if the buffer is
1337  * not large enough.
1338  *
1339  * Returns 0 on success.
1340  */
1341 int proc_dostring(ctl_table *table, int write, struct file *filp,
1342                   void __user *buffer, size_t *lenp)
1343 {
1344         size_t len;
1345         char __user *p;
1346         char c;
1347
1348         if (!table->data || !table->maxlen || !*lenp ||
1349             (filp->f_pos && !write)) {
1350                 *lenp = 0;
1351                 return 0;
1352         }
1353
1354         if (write) {
1355                 len = 0;
1356                 p = buffer;
1357                 while (len < *lenp) {
1358                         if (get_user(c, p++))
1359                                 return -EFAULT;
1360                         if (c == 0 || c == '\n')
1361                                 break;
1362                         len++;
1363                 }
1364                 if (len >= table->maxlen)
1365                         len = table->maxlen-1;
1366                 if(copy_from_user(table->data, buffer, len))
1367                         return -EFAULT;
1368                 ((char *) table->data)[len] = 0;
1369                 filp->f_pos += *lenp;
1370         } else {
1371                 len = strlen(table->data);
1372                 if (len > table->maxlen)
1373                         len = table->maxlen;
1374                 if (len > *lenp)
1375                         len = *lenp;
1376                 if (len)
1377                         if(copy_to_user(buffer, table->data, len))
1378                                 return -EFAULT;
1379                 if (len < *lenp) {
1380                         if(put_user('\n', ((char *) buffer) + len))
1381                                 return -EFAULT;
1382                         len++;
1383                 }
1384                 *lenp = len;
1385                 filp->f_pos += len;
1386         }
1387         return 0;
1388 }
1389
1390 /*
1391  *      Special case of dostring for the UTS structure. This has locks
1392  *      to observe. Should this be in kernel/sys.c ????
1393  */
1394
1395 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1396                   void __user *buffer, size_t *lenp)
1397 {
1398         int r;
1399
1400         if (!write) {
1401                 down_read(&uts_sem);
1402                 r=proc_dostring(table,0,filp,buffer,lenp);
1403                 up_read(&uts_sem);
1404         } else {
1405                 down_write(&uts_sem);
1406                 r=proc_dostring(table,1,filp,buffer,lenp);
1407                 up_write(&uts_sem);
1408         }
1409         return r;
1410 }
1411
1412 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1413                                  int *valp,
1414                                  int write, void *data)
1415 {
1416         if (write) {
1417                 *valp = *negp ? -*lvalp : *lvalp;
1418         } else {
1419                 int val = *valp;
1420                 if (val < 0) {
1421                         *negp = -1;
1422                         *lvalp = (unsigned long)-val;
1423                 } else {
1424                         *negp = 0;
1425                         *lvalp = (unsigned long)val;
1426                 }
1427         }
1428         return 0;
1429 }
1430
1431 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1432                   void __user *buffer, size_t *lenp,
1433                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1434                               int write, void *data),
1435                   void *data)
1436 {
1437 #define TMPBUFLEN 20
1438         int *i, vleft, first=1, neg, val;
1439         unsigned long lval;
1440         size_t left, len;
1441
1442         char buf[TMPBUFLEN], *p;
1443
1444         if (!table->data || !table->maxlen || !*lenp ||
1445             (filp->f_pos && !write)) {
1446                 *lenp = 0;
1447                 return 0;
1448         }
1449
1450         i = (int *) table->data;
1451         vleft = table->maxlen / sizeof(*i);
1452         left = *lenp;
1453
1454         if (!conv)
1455                 conv = do_proc_dointvec_conv;
1456
1457         for (; left && vleft--; i++, first=0) {
1458                 if (write) {
1459                         while (left) {
1460                                 char c;
1461                                 if (get_user(c,(char __user *) buffer))
1462                                         return -EFAULT;
1463                                 if (!isspace(c))
1464                                         break;
1465                                 left--;
1466                                 buffer++;
1467                         }
1468                         if (!left)
1469                                 break;
1470                         neg = 0;
1471                         len = left;
1472                         if (len > sizeof(buf) - 1)
1473                                 len = sizeof(buf) - 1;
1474                         if(copy_from_user(buf, buffer, len))
1475                                 return -EFAULT;
1476                         buf[len] = 0;
1477                         p = buf;
1478                         if (*p == '-' && left > 1) {
1479                                 neg = 1;
1480                                 left--, p++;
1481                         }
1482                         if (*p < '0' || *p > '9')
1483                                 break;
1484
1485                         lval = simple_strtoul(p, &p, 0);
1486
1487                         len = p-buf;
1488                         if ((len < left) && *p && !isspace(*p))
1489                                 break;
1490                         if (neg)
1491                                 val = -val;
1492                         buffer += len;
1493                         left -= len;
1494
1495                         if (conv(&neg, &lval, i, 1, data))
1496                                 break;
1497                 } else {
1498                         p = buf;
1499                         if (!first)
1500                                 *p++ = '\t';
1501
1502                         if (conv(&neg, &lval, i, 0, data))
1503                                 break;
1504
1505                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1506                         len = strlen(buf);
1507                         if (len > left)
1508                                 len = left;
1509                         if(copy_to_user(buffer, buf, len))
1510                                 return -EFAULT;
1511                         left -= len;
1512                         buffer += len;
1513                 }
1514         }
1515
1516         if (!write && !first && left) {
1517                 if(put_user('\n', (char *) buffer))
1518                         return -EFAULT;
1519                 left--, buffer++;
1520         }
1521         if (write) {
1522                 p = (char *) buffer;
1523                 while (left) {
1524                         char c;
1525                         if (get_user(c, p++))
1526                                 return -EFAULT;
1527                         if (!isspace(c))
1528                                 break;
1529                         left--;
1530                 }
1531         }
1532         if (write && first)
1533                 return -EINVAL;
1534         *lenp -= left;
1535         filp->f_pos += *lenp;
1536         return 0;
1537 #undef TMPBUFLEN
1538 }
1539
1540 /**
1541  * proc_dointvec - read a vector of integers
1542  * @table: the sysctl table
1543  * @write: %TRUE if this is a write to the sysctl file
1544  * @filp: the file structure
1545  * @buffer: the user buffer
1546  * @lenp: the size of the user buffer
1547  *
1548  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1549  * values from/to the user buffer, treated as an ASCII string.
1550  *
1551  * Returns 0 on success.
1552  */
1553 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1554                      void __user *buffer, size_t *lenp)
1555 {
1556     return do_proc_dointvec(table,write,filp,buffer,lenp,
1557                             NULL,NULL);
1558 }
1559
1560 #define OP_SET  0
1561 #define OP_AND  1
1562 #define OP_OR   2
1563 #define OP_MAX  3
1564 #define OP_MIN  4
1565
1566 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1567                                       int *valp,
1568                                       int write, void *data)
1569 {
1570         int op = *(int *)data;
1571         if (write) {
1572                 int val = *negp ? -*lvalp : *lvalp;
1573                 switch(op) {
1574                 case OP_SET:    *valp = val; break;
1575                 case OP_AND:    *valp &= val; break;
1576                 case OP_OR:     *valp |= val; break;
1577                 case OP_MAX:    if(*valp < val)
1578                                         *valp = val;
1579                                 break;
1580                 case OP_MIN:    if(*valp > val)
1581                                 *valp = val;
1582                                 break;
1583                 }
1584         } else {
1585                 int val = *valp;
1586                 if (val < 0) {
1587                         *negp = -1;
1588                         *lvalp = (unsigned long)-val;
1589                 } else {
1590                         *negp = 0;
1591                         *lvalp = (unsigned long)val;
1592                 }
1593         }
1594         return 0;
1595 }
1596
1597 /*
1598  *      init may raise the set.
1599  */
1600
1601 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1602                         void __user *buffer, size_t *lenp)
1603 {
1604         int op;
1605
1606         if (!capable(CAP_SYS_MODULE)) {
1607                 return -EPERM;
1608         }
1609
1610         op = (current->pid == 1) ? OP_SET : OP_AND;
1611         return do_proc_dointvec(table,write,filp,buffer,lenp,
1612                                 do_proc_dointvec_bset_conv,&op);
1613 }
1614
1615 struct do_proc_dointvec_minmax_conv_param {
1616         int *min;
1617         int *max;
1618 };
1619
1620 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1621                                         int *valp,
1622                                         int write, void *data)
1623 {
1624         struct do_proc_dointvec_minmax_conv_param *param = data;
1625         if (write) {
1626                 int val = *negp ? -*lvalp : *lvalp;
1627                 if ((param->min && *param->min > val) ||
1628                     (param->max && *param->max < val))
1629                         return -EINVAL;
1630                 *valp = val;
1631         } else {
1632                 int val = *valp;
1633                 if (val < 0) {
1634                         *negp = -1;
1635                         *lvalp = (unsigned long)-val;
1636                 } else {
1637                         *negp = 0;
1638                         *lvalp = (unsigned long)val;
1639                 }
1640         }
1641         return 0;
1642 }
1643
1644 /**
1645  * proc_dointvec_minmax - read a vector of integers with min/max values
1646  * @table: the sysctl table
1647  * @write: %TRUE if this is a write to the sysctl file
1648  * @filp: the file structure
1649  * @buffer: the user buffer
1650  * @lenp: the size of the user buffer
1651  *
1652  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1653  * values from/to the user buffer, treated as an ASCII string.
1654  *
1655  * This routine will ensure the values are within the range specified by
1656  * table->extra1 (min) and table->extra2 (max).
1657  *
1658  * Returns 0 on success.
1659  */
1660 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1661                   void __user *buffer, size_t *lenp)
1662 {
1663         struct do_proc_dointvec_minmax_conv_param param = {
1664                 .min = (int *) table->extra1,
1665                 .max = (int *) table->extra2,
1666         };
1667         return do_proc_dointvec(table, write, filp, buffer, lenp,
1668                                 do_proc_dointvec_minmax_conv, &param);
1669 }
1670
1671 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1672                                      struct file *filp,
1673                                      void __user *buffer, size_t *lenp,
1674                                      unsigned long convmul,
1675                                      unsigned long convdiv)
1676 {
1677 #define TMPBUFLEN 20
1678         unsigned long *i, *min, *max, val;
1679         int vleft, first=1, neg;
1680         size_t len, left;
1681         char buf[TMPBUFLEN], *p;
1682
1683         if (!table->data || !table->maxlen || !*lenp ||
1684             (filp->f_pos && !write)) {
1685                 *lenp = 0;
1686                 return 0;
1687         }
1688
1689         i = (unsigned long *) table->data;
1690         min = (unsigned long *) table->extra1;
1691         max = (unsigned long *) table->extra2;
1692         vleft = table->maxlen / sizeof(unsigned long);
1693         left = *lenp;
1694
1695         for (; left && vleft--; i++, min++, max++, first=0) {
1696                 if (write) {
1697                         while (left) {
1698                                 char c;
1699                                 if (get_user(c, (char __user *) buffer))
1700                                         return -EFAULT;
1701                                 if (!isspace(c))
1702                                         break;
1703                                 left--;
1704                                 buffer++;
1705                         }
1706                         if (!left)
1707                                 break;
1708                         neg = 0;
1709                         len = left;
1710                         if (len > TMPBUFLEN-1)
1711                                 len = TMPBUFLEN-1;
1712                         if (copy_from_user(buf, buffer, len))
1713                                 return -EFAULT;
1714                         buf[len] = 0;
1715                         p = buf;
1716                         if (*p == '-' && left > 1) {
1717                                 neg = 1;
1718                                 left--, p++;
1719                         }
1720                         if (*p < '0' || *p > '9')
1721                                 break;
1722                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1723                         len = p-buf;
1724                         if ((len < left) && *p && !isspace(*p))
1725                                 break;
1726                         if (neg)
1727                                 val = -val;
1728                         buffer += len;
1729                         left -= len;
1730
1731                         if(neg)
1732                                 continue;
1733                         if ((min && val < *min) || (max && val > *max))
1734                                 continue;
1735                         *i = val;
1736                 } else {
1737                         p = buf;
1738                         if (!first)
1739                                 *p++ = '\t';
1740                         sprintf(p, "%lu", convdiv * (*i) / convmul);
1741                         len = strlen(buf);
1742                         if (len > left)
1743                                 len = left;
1744                         if(copy_to_user(buffer, buf, len))
1745                                 return -EFAULT;
1746                         left -= len;
1747                         buffer += len;
1748                 }
1749         }
1750
1751         if (!write && !first && left) {
1752                 if(put_user('\n', (char *) buffer))
1753                         return -EFAULT;
1754                 left--, buffer++;
1755         }
1756         if (write) {
1757                 p = (char *) buffer;
1758                 while (left) {
1759                         char c;
1760                         if (get_user(c, p++))
1761                                 return -EFAULT;
1762                         if (!isspace(c))
1763                                 break;
1764                         left--;
1765                 }
1766         }
1767         if (write && first)
1768                 return -EINVAL;
1769         *lenp -= left;
1770         filp->f_pos += *lenp;
1771         return 0;
1772 #undef TMPBUFLEN
1773 }
1774
1775 /**
1776  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1777  * @table: the sysctl table
1778  * @write: %TRUE if this is a write to the sysctl file
1779  * @filp: the file structure
1780  * @buffer: the user buffer
1781  * @lenp: the size of the user buffer
1782  *
1783  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1784  * values from/to the user buffer, treated as an ASCII string.
1785  *
1786  * This routine will ensure the values are within the range specified by
1787  * table->extra1 (min) and table->extra2 (max).
1788  *
1789  * Returns 0 on success.
1790  */
1791 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1792                            void __user *buffer, size_t *lenp)
1793 {
1794     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, 1l, 1l);
1795 }
1796
1797 /**
1798  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1799  * @table: the sysctl table
1800  * @write: %TRUE if this is a write to the sysctl file
1801  * @filp: the file structure
1802  * @buffer: the user buffer
1803  * @lenp: the size of the user buffer
1804  *
1805  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1806  * values from/to the user buffer, treated as an ASCII string. The values
1807  * are treated as milliseconds, and converted to jiffies when they are stored.
1808  *
1809  * This routine will ensure the values are within the range specified by
1810  * table->extra1 (min) and table->extra2 (max).
1811  *
1812  * Returns 0 on success.
1813  */
1814 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1815                                       struct file *filp,
1816                                       void __user *buffer, size_t *lenp)
1817 {
1818     return do_proc_doulongvec_minmax(table, write, filp, buffer,
1819                                      lenp, HZ, 1000l);
1820 }
1821
1822
1823 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
1824                                          int *valp,
1825                                          int write, void *data)
1826 {
1827         if (write) {
1828                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1829         } else {
1830                 int val = *valp;
1831                 unsigned long lval;
1832                 if (val < 0) {
1833                         *negp = -1;
1834                         lval = (unsigned long)-val;
1835                 } else {
1836                         *negp = 0;
1837                         lval = (unsigned long)val;
1838                 }
1839                 *lvalp = lval / HZ;
1840         }
1841         return 0;
1842 }
1843
1844 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
1845                                                 int *valp,
1846                                                 int write, void *data)
1847 {
1848         if (write) {
1849                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
1850         } else {
1851                 int val = *valp;
1852                 unsigned long lval;
1853                 if (val < 0) {
1854                         *negp = -1;
1855                         lval = (unsigned long)-val;
1856                 } else {
1857                         *negp = 0;
1858                         lval = (unsigned long)val;
1859                 }
1860                 *lvalp = jiffies_to_clock_t(lval);
1861         }
1862         return 0;
1863 }
1864
1865 /**
1866  * proc_dointvec_jiffies - read a vector of integers as seconds
1867  * @table: the sysctl table
1868  * @write: %TRUE if this is a write to the sysctl file
1869  * @filp: the file structure
1870  * @buffer: the user buffer
1871  * @lenp: the size of the user buffer
1872  *
1873  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1874  * values from/to the user buffer, treated as an ASCII string.
1875  * The values read are assumed to be in seconds, and are converted into
1876  * jiffies.
1877  *
1878  * Returns 0 on success.
1879  */
1880 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
1881                           void __user *buffer, size_t *lenp)
1882 {
1883     return do_proc_dointvec(table,write,filp,buffer,lenp,
1884                             do_proc_dointvec_jiffies_conv,NULL);
1885 }
1886
1887 /**
1888  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
1889  * @table: the sysctl table
1890  * @write: %TRUE if this is a write to the sysctl file
1891  * @filp: the file structure
1892  * @buffer: the user buffer
1893  * @lenp: the size of the user buffer
1894  *
1895  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1896  * values from/to the user buffer, treated as an ASCII string.
1897  * The values read are assumed to be in 1/USER_HZ seconds, and
1898  * are converted into jiffies.
1899  *
1900  * Returns 0 on success.
1901  */
1902 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
1903                                  void __user *buffer, size_t *lenp)
1904 {
1905     return do_proc_dointvec(table,write,filp,buffer,lenp,
1906                             do_proc_dointvec_userhz_jiffies_conv,NULL);
1907 }
1908
1909 #else /* CONFIG_PROC_FS */
1910
1911 int proc_dostring(ctl_table *table, int write, struct file *filp,
1912                   void *buffer, size_t *lenp)
1913 {
1914         return -ENOSYS;
1915 }
1916
1917 static int proc_doutsstring(ctl_table *table, int write, struct file *filp,
1918                             void *buffer, size_t *lenp)
1919 {
1920         return -ENOSYS;
1921 }
1922
1923 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1924                   void *buffer, size_t *lenp)
1925 {
1926         return -ENOSYS;
1927 }
1928
1929 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1930                         void *buffer, size_t *lenp)
1931 {
1932         return -ENOSYS;
1933 }
1934
1935 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1936                     void *buffer, size_t *lenp)
1937 {
1938         return -ENOSYS;
1939 }
1940
1941 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
1942                     void *buffer, size_t *lenp)
1943 {
1944         return -ENOSYS;
1945 }
1946
1947 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
1948                     void *buffer, size_t *lenp)
1949 {
1950         return -ENOSYS;
1951 }
1952
1953 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1954                     void *buffer, size_t *lenp)
1955 {
1956         return -ENOSYS;
1957 }
1958
1959 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1960                                       struct file *filp,
1961                                       void *buffer, size_t *lenp)
1962 {
1963     return -ENOSYS;
1964 }
1965
1966
1967 #endif /* CONFIG_PROC_FS */
1968
1969
1970 /*
1971  * General sysctl support routines
1972  */
1973
1974 /* The generic string strategy routine: */
1975 int sysctl_string(ctl_table *table, int __user *name, int nlen,
1976                   void __user *oldval, size_t __user *oldlenp,
1977                   void __user *newval, size_t newlen, void **context)
1978 {
1979         size_t l, len;
1980
1981         if (!table->data || !table->maxlen)
1982                 return -ENOTDIR;
1983
1984         if (oldval && oldlenp) {
1985                 if (get_user(len, oldlenp))
1986                         return -EFAULT;
1987                 if (len) {
1988                         l = strlen(table->data);
1989                         if (len > l) len = l;
1990                         if (len >= table->maxlen)
1991                                 len = table->maxlen;
1992                         if(copy_to_user(oldval, table->data, len))
1993                                 return -EFAULT;
1994                         if(put_user(0, ((char *) oldval) + len))
1995                                 return -EFAULT;
1996                         if(put_user(len, oldlenp))
1997                                 return -EFAULT;
1998                 }
1999         }
2000         if (newval && newlen) {
2001                 len = newlen;
2002                 if (len > table->maxlen)
2003                         len = table->maxlen;
2004                 if(copy_from_user(table->data, newval, len))
2005                         return -EFAULT;
2006                 if (len == table->maxlen)
2007                         len--;
2008                 ((char *) table->data)[len] = 0;
2009         }
2010         return 0;
2011 }
2012
2013 /*
2014  * This function makes sure that all of the integers in the vector
2015  * are between the minimum and maximum values given in the arrays
2016  * table->extra1 and table->extra2, respectively.
2017  */
2018 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2019                 void __user *oldval, size_t __user *oldlenp,
2020                 void __user *newval, size_t newlen, void **context)
2021 {
2022         int i, *vec, *min, *max;
2023         size_t length;
2024
2025         if (newval && newlen) {
2026                 if (newlen % sizeof(int) != 0)
2027                         return -EINVAL;
2028
2029                 if (!table->extra1 && !table->extra2)
2030                         return 0;
2031
2032                 if (newlen > table->maxlen)
2033                         newlen = table->maxlen;
2034                 length = newlen / sizeof(int);
2035
2036                 vec = (int *) newval;
2037                 min = (int *) table->extra1;
2038                 max = (int *) table->extra2;
2039
2040                 for (i = 0; i < length; i++) {
2041                         int value;
2042                         if (get_user(value, vec + i))
2043                                 return -EFAULT;
2044                         if (min && value < min[i])
2045                                 return -EINVAL;
2046                         if (max && value > max[i])
2047                                 return -EINVAL;
2048                 }
2049         }
2050         return 0;
2051 }
2052
2053 /* Strategy function to convert jiffies to seconds */
2054 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2055                 void __user *oldval, size_t __user *oldlenp,
2056                 void __user *newval, size_t newlen, void **context)
2057 {
2058         if (oldval) {
2059                 size_t olen;
2060                 if (oldlenp) {
2061                         if (get_user(olen, oldlenp))
2062                                 return -EFAULT;
2063                         if (olen!=sizeof(int))
2064                                 return -EINVAL;
2065                 }
2066                 if (put_user(*(int *)(table->data) / HZ, (int *)oldval) ||
2067                     (oldlenp && put_user(sizeof(int),oldlenp)))
2068                         return -EFAULT;
2069         }
2070         if (newval && newlen) {
2071                 int new;
2072                 if (newlen != sizeof(int))
2073                         return -EINVAL;
2074                 if (get_user(new, (int *)newval))
2075                         return -EFAULT;
2076                 *(int *)(table->data) = new*HZ;
2077         }
2078         return 1;
2079 }
2080
2081
2082 #else /* CONFIG_SYSCTL */
2083
2084
2085 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2086 {
2087         return -ENOSYS;
2088 }
2089
2090 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2091                   void __user *oldval, size_t __user *oldlenp,
2092                   void __user *newval, size_t newlen, void **context)
2093 {
2094         return -ENOSYS;
2095 }
2096
2097 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2098                 void __user *oldval, size_t __user *oldlenp,
2099                 void __user *newval, size_t newlen, void **context)
2100 {
2101         return -ENOSYS;
2102 }
2103
2104 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2105                 void __user *oldval, size_t __user *oldlenp,
2106                 void __user *newval, size_t newlen, void **context)
2107 {
2108         return -ENOSYS;
2109 }
2110
2111 int proc_dostring(ctl_table *table, int write, struct file *filp,
2112                   void __user *buffer, size_t *lenp)
2113 {
2114         return -ENOSYS;
2115 }
2116
2117 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2118                   void __user *buffer, size_t *lenp)
2119 {
2120         return -ENOSYS;
2121 }
2122
2123 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2124                         void __user *buffer, size_t *lenp)
2125 {
2126         return -ENOSYS;
2127 }
2128
2129 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2130                     void __user *buffer, size_t *lenp)
2131 {
2132         return -ENOSYS;
2133 }
2134
2135 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2136                           void *buffer, size_t *lenp)
2137 {
2138         return -ENOSYS;
2139 }
2140
2141 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2142                           void *buffer, size_t *lenp)
2143 {
2144         return -ENOSYS;
2145 }
2146
2147 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2148                     void __user *buffer, size_t *lenp)
2149 {
2150         return -ENOSYS;
2151 }
2152
2153 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2154                                       struct file *filp,
2155                                       void __user *buffer, size_t *lenp)
2156 {
2157     return -ENOSYS;
2158 }
2159
2160 struct ctl_table_header * register_sysctl_table(ctl_table * table,
2161                                                 int insert_at_head)
2162 {
2163         return 0;
2164 }
2165
2166 void unregister_sysctl_table(struct ctl_table_header * table)
2167 {
2168 }
2169
2170 #endif /* CONFIG_SYSCTL */
2171
2172 /*
2173  * No sense putting this after each symbol definition, twice,
2174  * exception granted :-)
2175  */
2176 EXPORT_SYMBOL(proc_dointvec);
2177 EXPORT_SYMBOL(proc_dointvec_jiffies);
2178 EXPORT_SYMBOL(proc_dointvec_minmax);
2179 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2180 EXPORT_SYMBOL(proc_dostring);
2181 EXPORT_SYMBOL(proc_doulongvec_minmax);
2182 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2183 EXPORT_SYMBOL(register_sysctl_table);
2184 EXPORT_SYMBOL(sysctl_intvec);
2185 EXPORT_SYMBOL(sysctl_jiffies);
2186 EXPORT_SYMBOL(sysctl_string);
2187 EXPORT_SYMBOL(unregister_sysctl_table);