kernel/sysctl.c

   1 /*
   2  * sysctl.c: General linux system control interface
   3  *
   4  * Begun 24 March 1995, Stephen Tweedie
   5  * Added /proc support, Dec 1995
   6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
   7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
   8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
   9  * Dynamic registration fixes, Stephen Tweedie.
  10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
  11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
  12  *  Horn.
  13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
  14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
  15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
  16  *  Wendling.
  17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
  18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/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 #include <asm/stacktrace.h>
  58 #endif
  59
  60 #if defined(CONFIG_SYSCTL)
  61
  62 /* External variables not in a header file. */
  63 extern int C_A_D;
  64 extern int sysctl_overcommit_memory;
  65 extern int sysctl_overcommit_ratio;
  66 extern int sysctl_panic_on_oom;
  67 extern int max_threads;
  68 extern int core_uses_pid;
  69 extern int suid_dumpable;
  70 extern char core_pattern[];
  71 extern int pid_max;
  72 extern int min_free_kbytes;
  73 extern int printk_ratelimit_jiffies;
  74 extern int printk_ratelimit_burst;
  75 extern int pid_max_min, pid_max_max;
  76 extern int sysctl_drop_caches;
  77 extern int percpu_pagelist_fraction;
  78 extern int compat_log;
  79
  80 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
  81 static int maxolduid = 65535;
  82 static int minolduid;
  83 static int min_percpu_pagelist_fract = 8;
  84
  85 static int ngroups_max = NGROUPS_MAX;
  86
  87 #ifdef CONFIG_KMOD
  88 extern char modprobe_path[];
  89 #endif
  90 #ifdef CONFIG_CHR_DEV_SG
  91 extern int sg_big_buff;
  92 #endif
  93 #ifdef CONFIG_SYSVIPC
  94 static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
  95                 void __user *buffer, size_t *lenp, loff_t *ppos);
  96 static int proc_ipc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
  97                 void __user *buffer, size_t *lenp, loff_t *ppos);
  98 #endif
  99
 100 #ifdef __sparc__
 101 extern char reboot_command [];
 102 extern int stop_a_enabled;
 103 extern int scons_pwroff;
 104 #endif
 105
 106 #ifdef __hppa__
 107 extern int pwrsw_enabled;
 108 extern int unaligned_enabled;
 109 #endif
 110
 111 #ifdef CONFIG_S390
 112 #ifdef CONFIG_MATHEMU
 113 extern int sysctl_ieee_emulation_warnings;
 114 #endif
 115 extern int sysctl_userprocess_debug;
 116 extern int spin_retry;
 117 #endif
 118
 119 extern int sysctl_hz_timer;
 120
 121 #ifdef CONFIG_BSD_PROCESS_ACCT
 122 extern int acct_parm[];
 123 #endif
 124
 125 #ifdef CONFIG_IA64
 126 extern int no_unaligned_warning;
 127 #endif
 128
 129 #ifdef CONFIG_RT_MUTEXES
 130 extern int max_lock_depth;
 131 #endif
 132
 133 #ifdef CONFIG_SYSCTL_SYSCALL
 134 static int parse_table(int __user *, int, void __user *, size_t __user *,
 135                 void __user *, size_t, ctl_table *);
 136 #endif
 137
 138 static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
 139                   void __user *buffer, size_t *lenp, loff_t *ppos);
 140
 141 static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen,
 142                   void __user *oldval, size_t __user *oldlenp,
 143                   void __user *newval, size_t newlen);
 144
 145 #ifdef CONFIG_SYSVIPC
 146 static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
 147                   void __user *oldval, size_t __user *oldlenp,
 148                   void __user *newval, size_t newlen);
 149 #endif
 150
 151 #ifdef CONFIG_PROC_SYSCTL
 152 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
 153                   void __user *buffer, size_t *lenp, loff_t *ppos);
 154 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
 155                                void __user *buffer, size_t *lenp, loff_t *ppos);
 156 #endif
 157
 158 static ctl_table root_table[];
 159 static struct ctl_table_header root_table_header =
 160         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
 161
 162 static ctl_table kern_table[];
 163 static ctl_table vm_table[];
 164 static ctl_table fs_table[];
 165 static ctl_table debug_table[];
 166 static ctl_table dev_table[];
 167 extern ctl_table random_table[];
 168 #ifdef CONFIG_UNIX98_PTYS
 169 extern ctl_table pty_table[];
 170 #endif
 171 #ifdef CONFIG_INOTIFY_USER
 172 extern ctl_table inotify_table[];
 173 #endif
 174
 175 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 176 int sysctl_legacy_va_layout;
 177 #endif
 178
 179
 180 static void *get_uts(ctl_table *table, int write)
 181 {
 182         char *which = table->data;
 183 #ifdef CONFIG_UTS_NS
 184         struct uts_namespace *uts_ns = current->nsproxy->uts_ns;
 185         which = (which - (char *)&init_uts_ns) + (char *)uts_ns;
 186 #endif
 187         if (!write)
 188                 down_read(&uts_sem);
 189         else
 190                 down_write(&uts_sem);
 191         return which;
 192 }
 193
 194 static void put_uts(ctl_table *table, int write, void *which)
 195 {
 196         if (!write)
 197                 up_read(&uts_sem);
 198         else
 199                 up_write(&uts_sem);
 200 }
 201
 202 #ifdef CONFIG_SYSVIPC
 203 static void *get_ipc(ctl_table *table, int write)
 204 {
 205         char *which = table->data;
 206         struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
 207         which = (which - (char *)&init_ipc_ns) + (char *)ipc_ns;
 208         return which;
 209 }
 210 #else
 211 #define get_ipc(T,W) ((T)->data)
 212 #endif
 213
 214 /* /proc declarations: */
 215
 216 #ifdef CONFIG_PROC_SYSCTL
 217
 218 static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
 219 static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
 220 static int proc_opensys(struct inode *, struct file *);
 221
 222 const struct file_operations proc_sys_file_operations = {
 223         .open           = proc_opensys,
 224         .read           = proc_readsys,
 225         .write          = proc_writesys,
 226 };
 227
 228 extern struct proc_dir_entry *proc_sys_root;
 229
 230 static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
 231 static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
 232 #endif
 233
 234 /* The default sysctl tables: */
 235
 236 static ctl_table root_table[] = {
 237         {
 238                 .ctl_name       = CTL_KERN,
 239                 .procname       = "kernel",
 240                 .mode           = 0555,
 241                 .child          = kern_table,
 242         },
 243         {
 244                 .ctl_name       = CTL_VM,
 245                 .procname       = "vm",
 246                 .mode           = 0555,
 247                 .child          = vm_table,
 248         },
 249 #ifdef CONFIG_NET
 250         {
 251                 .ctl_name       = CTL_NET,
 252                 .procname       = "net",
 253                 .mode           = 0555,
 254                 .child          = net_table,
 255         },
 256 #endif
 257         {
 258                 .ctl_name       = CTL_FS,
 259                 .procname       = "fs",
 260                 .mode           = 0555,
 261                 .child          = fs_table,
 262         },
 263         {
 264                 .ctl_name       = CTL_DEBUG,
 265                 .procname       = "debug",
 266                 .mode           = 0555,
 267                 .child          = debug_table,
 268         },
 269         {
 270                 .ctl_name       = CTL_DEV,
 271                 .procname       = "dev",
 272                 .mode           = 0555,
 273                 .child          = dev_table,
 274         },
 275
 276         { .ctl_name = 0 }
 277 };
 278
 279 static ctl_table kern_table[] = {
 280         {
 281                 .ctl_name       = KERN_OSTYPE,
 282                 .procname       = "ostype",
 283                 .data           = init_uts_ns.name.sysname,
 284                 .maxlen         = sizeof(init_uts_ns.name.sysname),
 285                 .mode           = 0444,
 286                 .proc_handler   = &proc_do_uts_string,
 287                 .strategy       = &sysctl_uts_string,
 288         },
 289         {
 290                 .ctl_name       = KERN_OSRELEASE,
 291                 .procname       = "osrelease",
 292                 .data           = init_uts_ns.name.release,
 293                 .maxlen         = sizeof(init_uts_ns.name.release),
 294                 .mode           = 0444,
 295                 .proc_handler   = &proc_do_uts_string,
 296                 .strategy       = &sysctl_uts_string,
 297         },
 298         {
 299                 .ctl_name       = KERN_VERSION,
 300                 .procname       = "version",
 301                 .data           = init_uts_ns.name.version,
 302                 .maxlen         = sizeof(init_uts_ns.name.version),
 303                 .mode           = 0444,
 304                 .proc_handler   = &proc_do_uts_string,
 305                 .strategy       = &sysctl_uts_string,
 306         },
 307         {
 308                 .ctl_name       = KERN_NODENAME,
 309                 .procname       = "hostname",
 310                 .data           = init_uts_ns.name.nodename,
 311                 .maxlen         = sizeof(init_uts_ns.name.nodename),
 312                 .mode           = 0644,
 313                 .proc_handler   = &proc_do_uts_string,
 314                 .strategy       = &sysctl_uts_string,
 315         },
 316         {
 317                 .ctl_name       = KERN_DOMAINNAME,
 318                 .procname       = "domainname",
 319                 .data           = init_uts_ns.name.domainname,
 320                 .maxlen         = sizeof(init_uts_ns.name.domainname),
 321                 .mode           = 0644,
 322                 .proc_handler   = &proc_do_uts_string,
 323                 .strategy       = &sysctl_uts_string,
 324         },
 325         {
 326                 .ctl_name       = KERN_PANIC,
 327                 .procname       = "panic",
 328                 .data           = &panic_timeout,
 329                 .maxlen         = sizeof(int),
 330                 .mode           = 0644,
 331                 .proc_handler   = &proc_dointvec,
 332         },
 333         {
 334                 .ctl_name       = KERN_CORE_USES_PID,
 335                 .procname       = "core_uses_pid",
 336                 .data           = &core_uses_pid,
 337                 .maxlen         = sizeof(int),
 338                 .mode           = 0644,
 339                 .proc_handler   = &proc_dointvec,
 340         },
 341         {
 342                 .ctl_name       = KERN_CORE_PATTERN,
 343                 .procname       = "core_pattern",
 344                 .data           = core_pattern,
 345                 .maxlen         = 128,
 346                 .mode           = 0644,
 347                 .proc_handler   = &proc_dostring,
 348                 .strategy       = &sysctl_string,
 349         },
 350 #ifdef CONFIG_PROC_SYSCTL
 351         {
 352                 .ctl_name       = KERN_TAINTED,
 353                 .procname       = "tainted",
 354                 .data           = &tainted,
 355                 .maxlen         = sizeof(int),
 356                 .mode           = 0644,
 357                 .proc_handler   = &proc_dointvec_taint,
 358         },
 359 #endif
 360         {
 361                 .ctl_name       = KERN_CAP_BSET,
 362                 .procname       = "cap-bound",
 363                 .data           = &cap_bset,
 364                 .maxlen         = sizeof(kernel_cap_t),
 365                 .mode           = 0600,
 366                 .proc_handler   = &proc_dointvec_bset,
 367         },
 368 #ifdef CONFIG_BLK_DEV_INITRD
 369         {
 370                 .ctl_name       = KERN_REALROOTDEV,
 371                 .procname       = "real-root-dev",
 372                 .data           = &real_root_dev,
 373                 .maxlen         = sizeof(int),
 374                 .mode           = 0644,
 375                 .proc_handler   = &proc_dointvec,
 376         },
 377 #endif
 378 #ifdef __sparc__
 379         {
 380                 .ctl_name       = KERN_SPARC_REBOOT,
 381                 .procname       = "reboot-cmd",
 382                 .data           = reboot_command,
 383                 .maxlen         = 256,
 384                 .mode           = 0644,
 385                 .proc_handler   = &proc_dostring,
 386                 .strategy       = &sysctl_string,
 387         },
 388         {
 389                 .ctl_name       = KERN_SPARC_STOP_A,
 390                 .procname       = "stop-a",
 391                 .data           = &stop_a_enabled,
 392                 .maxlen         = sizeof (int),
 393                 .mode           = 0644,
 394                 .proc_handler   = &proc_dointvec,
 395         },
 396         {
 397                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
 398                 .procname       = "scons-poweroff",
 399                 .data           = &scons_pwroff,
 400                 .maxlen         = sizeof (int),
 401                 .mode           = 0644,
 402                 .proc_handler   = &proc_dointvec,
 403         },
 404 #endif
 405 #ifdef __hppa__
 406         {
 407                 .ctl_name       = KERN_HPPA_PWRSW,
 408                 .procname       = "soft-power",
 409                 .data           = &pwrsw_enabled,
 410                 .maxlen         = sizeof (int),
 411                 .mode           = 0644,
 412                 .proc_handler   = &proc_dointvec,
 413         },
 414         {
 415                 .ctl_name       = KERN_HPPA_UNALIGNED,
 416                 .procname       = "unaligned-trap",
 417                 .data           = &unaligned_enabled,
 418                 .maxlen         = sizeof (int),
 419                 .mode           = 0644,
 420                 .proc_handler   = &proc_dointvec,
 421         },
 422 #endif
 423         {
 424                 .ctl_name       = KERN_CTLALTDEL,
 425                 .procname       = "ctrl-alt-del",
 426                 .data           = &C_A_D,
 427                 .maxlen         = sizeof(int),
 428                 .mode           = 0644,
 429                 .proc_handler   = &proc_dointvec,
 430         },
 431         {
 432                 .ctl_name       = KERN_PRINTK,
 433                 .procname       = "printk",
 434                 .data           = &console_loglevel,
 435                 .maxlen         = 4*sizeof(int),
 436                 .mode           = 0644,
 437                 .proc_handler   = &proc_dointvec,
 438         },
 439 #ifdef CONFIG_KMOD
 440         {
 441                 .ctl_name       = KERN_MODPROBE,
 442                 .procname       = "modprobe",
 443                 .data           = &modprobe_path,
 444                 .maxlen         = KMOD_PATH_LEN,
 445                 .mode           = 0644,
 446                 .proc_handler   = &proc_dostring,
 447                 .strategy       = &sysctl_string,
 448         },
 449 #endif
 450 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
 451         {
 452                 .ctl_name       = KERN_HOTPLUG,
 453                 .procname       = "hotplug",
 454                 .data           = &uevent_helper,
 455                 .maxlen         = UEVENT_HELPER_PATH_LEN,
 456                 .mode           = 0644,
 457                 .proc_handler   = &proc_dostring,
 458                 .strategy       = &sysctl_string,
 459         },
 460 #endif
 461 #ifdef CONFIG_CHR_DEV_SG
 462         {
 463                 .ctl_name       = KERN_SG_BIG_BUFF,
 464                 .procname       = "sg-big-buff",
 465                 .data           = &sg_big_buff,
 466                 .maxlen         = sizeof (int),
 467                 .mode           = 0444,
 468                 .proc_handler   = &proc_dointvec,
 469         },
 470 #endif
 471 #ifdef CONFIG_BSD_PROCESS_ACCT
 472         {
 473                 .ctl_name       = KERN_ACCT,
 474                 .procname       = "acct",
 475                 .data           = &acct_parm,
 476                 .maxlen         = 3*sizeof(int),
 477                 .mode           = 0644,
 478                 .proc_handler   = &proc_dointvec,
 479         },
 480 #endif
 481 #ifdef CONFIG_SYSVIPC
 482         {
 483                 .ctl_name       = KERN_SHMMAX,
 484                 .procname       = "shmmax",
 485                 .data           = &init_ipc_ns.shm_ctlmax,
 486                 .maxlen         = sizeof (init_ipc_ns.shm_ctlmax),
 487                 .mode           = 0644,
 488                 .proc_handler   = &proc_ipc_doulongvec_minmax,
 489                 .strategy       = sysctl_ipc_data,
 490         },
 491         {
 492                 .ctl_name       = KERN_SHMALL,
 493                 .procname       = "shmall",
 494                 .data           = &init_ipc_ns.shm_ctlall,
 495                 .maxlen         = sizeof (init_ipc_ns.shm_ctlall),
 496                 .mode           = 0644,
 497                 .proc_handler   = &proc_ipc_doulongvec_minmax,
 498                 .strategy       = sysctl_ipc_data,
 499         },
 500         {
 501                 .ctl_name       = KERN_SHMMNI,
 502                 .procname       = "shmmni",
 503                 .data           = &init_ipc_ns.shm_ctlmni,
 504                 .maxlen         = sizeof (init_ipc_ns.shm_ctlmni),
 505                 .mode           = 0644,
 506                 .proc_handler   = &proc_ipc_dointvec,
 507                 .strategy       = sysctl_ipc_data,
 508         },
 509         {
 510                 .ctl_name       = KERN_MSGMAX,
 511                 .procname       = "msgmax",
 512                 .data           = &init_ipc_ns.msg_ctlmax,
 513                 .maxlen         = sizeof (init_ipc_ns.msg_ctlmax),
 514                 .mode           = 0644,
 515                 .proc_handler   = &proc_ipc_dointvec,
 516                 .strategy       = sysctl_ipc_data,
 517         },
 518         {
 519                 .ctl_name       = KERN_MSGMNI,
 520                 .procname       = "msgmni",
 521                 .data           = &init_ipc_ns.msg_ctlmni,
 522                 .maxlen         = sizeof (init_ipc_ns.msg_ctlmni),
 523                 .mode           = 0644,
 524                 .proc_handler   = &proc_ipc_dointvec,
 525                 .strategy       = sysctl_ipc_data,
 526         },
 527         {
 528                 .ctl_name       = KERN_MSGMNB,
 529                 .procname       =  "msgmnb",
 530                 .data           = &init_ipc_ns.msg_ctlmnb,
 531                 .maxlen         = sizeof (init_ipc_ns.msg_ctlmnb),
 532                 .mode           = 0644,
 533                 .proc_handler   = &proc_ipc_dointvec,
 534                 .strategy       = sysctl_ipc_data,
 535         },
 536         {
 537                 .ctl_name       = KERN_SEM,
 538                 .procname       = "sem",
 539                 .data           = &init_ipc_ns.sem_ctls,
 540                 .maxlen         = 4*sizeof (int),
 541                 .mode           = 0644,
 542                 .proc_handler   = &proc_ipc_dointvec,
 543                 .strategy       = sysctl_ipc_data,
 544         },
 545 #endif
 546 #ifdef CONFIG_MAGIC_SYSRQ
 547         {
 548                 .ctl_name       = KERN_SYSRQ,
 549                 .procname       = "sysrq",
 550                 .data           = &__sysrq_enabled,
 551                 .maxlen         = sizeof (int),
 552                 .mode           = 0644,
 553                 .proc_handler   = &proc_dointvec,
 554         },
 555 #endif
 556 #ifdef CONFIG_PROC_SYSCTL
 557         {
 558                 .ctl_name       = KERN_CADPID,
 559                 .procname       = "cad_pid",
 560                 .data           = NULL,
 561                 .maxlen         = sizeof (int),
 562                 .mode           = 0600,
 563                 .proc_handler   = &proc_do_cad_pid,
 564         },
 565 #endif
 566         {
 567                 .ctl_name       = KERN_MAX_THREADS,
 568                 .procname       = "threads-max",
 569                 .data           = &max_threads,
 570                 .maxlen         = sizeof(int),
 571                 .mode           = 0644,
 572                 .proc_handler   = &proc_dointvec,
 573         },
 574         {
 575                 .ctl_name       = KERN_RANDOM,
 576                 .procname       = "random",
 577                 .mode           = 0555,
 578                 .child          = random_table,
 579         },
 580 #ifdef CONFIG_UNIX98_PTYS
 581         {
 582                 .ctl_name       = KERN_PTY,
 583                 .procname       = "pty",
 584                 .mode           = 0555,
 585                 .child          = pty_table,
 586         },
 587 #endif
 588         {
 589                 .ctl_name       = KERN_OVERFLOWUID,
 590                 .procname       = "overflowuid",
 591                 .data           = &overflowuid,
 592                 .maxlen         = sizeof(int),
 593                 .mode           = 0644,
 594                 .proc_handler   = &proc_dointvec_minmax,
 595                 .strategy       = &sysctl_intvec,
 596                 .extra1         = &minolduid,
 597                 .extra2         = &maxolduid,
 598         },
 599         {
 600                 .ctl_name       = KERN_OVERFLOWGID,
 601                 .procname       = "overflowgid",
 602                 .data           = &overflowgid,
 603                 .maxlen         = sizeof(int),
 604                 .mode           = 0644,
 605                 .proc_handler   = &proc_dointvec_minmax,
 606                 .strategy       = &sysctl_intvec,
 607                 .extra1         = &minolduid,
 608                 .extra2         = &maxolduid,
 609         },
 610 #ifdef CONFIG_S390
 611 #ifdef CONFIG_MATHEMU
 612         {
 613                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
 614                 .procname       = "ieee_emulation_warnings",
 615                 .data           = &sysctl_ieee_emulation_warnings,
 616                 .maxlen         = sizeof(int),
 617                 .mode           = 0644,
 618                 .proc_handler   = &proc_dointvec,
 619         },
 620 #endif
 621 #ifdef CONFIG_NO_IDLE_HZ
 622         {
 623                 .ctl_name       = KERN_HZ_TIMER,
 624                 .procname       = "hz_timer",
 625                 .data           = &sysctl_hz_timer,
 626                 .maxlen         = sizeof(int),
 627                 .mode           = 0644,
 628                 .proc_handler   = &proc_dointvec,
 629         },
 630 #endif
 631         {
 632                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
 633                 .procname       = "userprocess_debug",
 634                 .data           = &sysctl_userprocess_debug,
 635                 .maxlen         = sizeof(int),
 636                 .mode           = 0644,
 637                 .proc_handler   = &proc_dointvec,
 638         },
 639 #endif
 640         {
 641                 .ctl_name       = KERN_PIDMAX,
 642                 .procname       = "pid_max",
 643                 .data           = &pid_max,
 644                 .maxlen         = sizeof (int),
 645                 .mode           = 0644,
 646                 .proc_handler   = &proc_dointvec_minmax,
 647                 .strategy       = sysctl_intvec,
 648                 .extra1         = &pid_max_min,
 649                 .extra2         = &pid_max_max,
 650         },
 651         {
 652                 .ctl_name       = KERN_PANIC_ON_OOPS,
 653                 .procname       = "panic_on_oops",
 654                 .data           = &panic_on_oops,
 655                 .maxlen         = sizeof(int),
 656                 .mode           = 0644,
 657                 .proc_handler   = &proc_dointvec,
 658         },
 659         {
 660                 .ctl_name       = KERN_PRINTK_RATELIMIT,
 661                 .procname       = "printk_ratelimit",
 662                 .data           = &printk_ratelimit_jiffies,
 663                 .maxlen         = sizeof(int),
 664                 .mode           = 0644,
 665                 .proc_handler   = &proc_dointvec_jiffies,
 666                 .strategy       = &sysctl_jiffies,
 667         },
 668         {
 669                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
 670                 .procname       = "printk_ratelimit_burst",
 671                 .data           = &printk_ratelimit_burst,
 672                 .maxlen         = sizeof(int),
 673                 .mode           = 0644,
 674                 .proc_handler   = &proc_dointvec,
 675         },
 676         {
 677                 .ctl_name       = KERN_NGROUPS_MAX,
 678                 .procname       = "ngroups_max",
 679                 .data           = &ngroups_max,
 680                 .maxlen         = sizeof (int),
 681                 .mode           = 0444,
 682                 .proc_handler   = &proc_dointvec,
 683         },
 684 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
 685         {
 686                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
 687                 .procname       = "unknown_nmi_panic",
 688                 .data           = &unknown_nmi_panic,
 689                 .maxlen         = sizeof (int),
 690                 .mode           = 0644,
 691                 .proc_handler   = &proc_dointvec,
 692         },
 693         {
 694                 .ctl_name       = KERN_NMI_WATCHDOG,
 695                 .procname       = "nmi_watchdog",
 696                 .data           = &nmi_watchdog_enabled,
 697                 .maxlen         = sizeof (int),
 698                 .mode           = 0644,
 699                 .proc_handler   = &proc_nmi_enabled,
 700         },
 701 #endif
 702 #if defined(CONFIG_X86)
 703         {
 704                 .ctl_name       = KERN_PANIC_ON_NMI,
 705                 .procname       = "panic_on_unrecovered_nmi",
 706                 .data           = &panic_on_unrecovered_nmi,
 707                 .maxlen         = sizeof(int),
 708                 .mode           = 0644,
 709                 .proc_handler   = &proc_dointvec,
 710         },
 711         {
 712                 .ctl_name       = KERN_BOOTLOADER_TYPE,
 713                 .procname       = "bootloader_type",
 714                 .data           = &bootloader_type,
 715                 .maxlen         = sizeof (int),
 716                 .mode           = 0444,
 717                 .proc_handler   = &proc_dointvec,
 718         },
 719         {
 720                 .ctl_name       = CTL_UNNUMBERED,
 721                 .procname       = "kstack_depth_to_print",
 722                 .data           = &kstack_depth_to_print,
 723                 .maxlen         = sizeof(int),
 724                 .mode           = 0644,
 725                 .proc_handler   = &proc_dointvec,
 726         },
 727 #endif
 728 #if defined(CONFIG_MMU)
 729         {
 730                 .ctl_name       = KERN_RANDOMIZE,
 731                 .procname       = "randomize_va_space",
 732                 .data           = &randomize_va_space,
 733                 .maxlen         = sizeof(int),
 734                 .mode           = 0644,
 735                 .proc_handler   = &proc_dointvec,
 736         },
 737 #endif
 738 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
 739         {
 740                 .ctl_name       = KERN_SPIN_RETRY,
 741                 .procname       = "spin_retry",
 742                 .data           = &spin_retry,
 743                 .maxlen         = sizeof (int),
 744                 .mode           = 0644,
 745                 .proc_handler   = &proc_dointvec,
 746         },
 747 #endif
 748 #ifdef CONFIG_ACPI_SLEEP
 749         {
 750                 .ctl_name       = KERN_ACPI_VIDEO_FLAGS,
 751                 .procname       = "acpi_video_flags",
 752                 .data           = &acpi_video_flags,
 753                 .maxlen         = sizeof (unsigned long),
 754                 .mode           = 0644,
 755                 .proc_handler   = &proc_doulongvec_minmax,
 756         },
 757 #endif
 758 #ifdef CONFIG_IA64
 759         {
 760                 .ctl_name       = KERN_IA64_UNALIGNED,
 761                 .procname       = "ignore-unaligned-usertrap",
 762                 .data           = &no_unaligned_warning,
 763                 .maxlen         = sizeof (int),
 764                 .mode           = 0644,
 765                 .proc_handler   = &proc_dointvec,
 766         },
 767 #endif
 768 #ifdef CONFIG_COMPAT
 769         {
 770                 .ctl_name       = KERN_COMPAT_LOG,
 771                 .procname       = "compat-log",
 772                 .data           = &compat_log,
 773                 .maxlen         = sizeof (int),
 774                 .mode           = 0644,
 775                 .proc_handler   = &proc_dointvec,
 776         },
 777 #endif
 778 #ifdef CONFIG_RT_MUTEXES
 779         {
 780                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
 781                 .procname       = "max_lock_depth",
 782                 .data           = &max_lock_depth,
 783                 .maxlen         = sizeof(int),
 784                 .mode           = 0644,
 785                 .proc_handler   = &proc_dointvec,
 786         },
 787 #endif
 788
 789         { .ctl_name = 0 }
 790 };
 791
 792 /* Constants for minimum and maximum testing in vm_table.
 793    We use these as one-element integer vectors. */
 794 static int zero;
 795 static int one_hundred = 100;
 796
 797
 798 static ctl_table vm_table[] = {
 799         {
 800                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
 801                 .procname       = "overcommit_memory",
 802                 .data           = &sysctl_overcommit_memory,
 803                 .maxlen         = sizeof(sysctl_overcommit_memory),
 804                 .mode           = 0644,
 805                 .proc_handler   = &proc_dointvec,
 806         },
 807         {
 808                 .ctl_name       = VM_PANIC_ON_OOM,
 809                 .procname       = "panic_on_oom",
 810                 .data           = &sysctl_panic_on_oom,
 811                 .maxlen         = sizeof(sysctl_panic_on_oom),
 812                 .mode           = 0644,
 813                 .proc_handler   = &proc_dointvec,
 814         },
 815         {
 816                 .ctl_name       = VM_OVERCOMMIT_RATIO,
 817                 .procname       = "overcommit_ratio",
 818                 .data           = &sysctl_overcommit_ratio,
 819                 .maxlen         = sizeof(sysctl_overcommit_ratio),
 820                 .mode           = 0644,
 821                 .proc_handler   = &proc_dointvec,
 822         },
 823         {
 824                 .ctl_name       = VM_PAGE_CLUSTER,
 825                 .procname       = "page-cluster",
 826                 .data           = &page_cluster,
 827                 .maxlen         = sizeof(int),
 828                 .mode           = 0644,
 829                 .proc_handler   = &proc_dointvec,
 830         },
 831         {
 832                 .ctl_name       = VM_DIRTY_BACKGROUND,
 833                 .procname       = "dirty_background_ratio",
 834                 .data           = &dirty_background_ratio,
 835                 .maxlen         = sizeof(dirty_background_ratio),
 836                 .mode           = 0644,
 837                 .proc_handler   = &proc_dointvec_minmax,
 838                 .strategy       = &sysctl_intvec,
 839                 .extra1         = &zero,
 840                 .extra2         = &one_hundred,
 841         },
 842         {
 843                 .ctl_name       = VM_DIRTY_RATIO,
 844                 .procname       = "dirty_ratio",
 845                 .data           = &vm_dirty_ratio,
 846                 .maxlen         = sizeof(vm_dirty_ratio),
 847                 .mode           = 0644,
 848                 .proc_handler   = &proc_dointvec_minmax,
 849                 .strategy       = &sysctl_intvec,
 850                 .extra1         = &zero,
 851                 .extra2         = &one_hundred,
 852         },
 853         {
 854                 .ctl_name       = VM_DIRTY_WB_CS,
 855                 .procname       = "dirty_writeback_centisecs",
 856                 .data           = &dirty_writeback_interval,
 857                 .maxlen         = sizeof(dirty_writeback_interval),
 858                 .mode           = 0644,
 859                 .proc_handler   = &dirty_writeback_centisecs_handler,
 860         },
 861         {
 862                 .ctl_name       = VM_DIRTY_EXPIRE_CS,
 863                 .procname       = "dirty_expire_centisecs",
 864                 .data           = &dirty_expire_interval,
 865                 .maxlen         = sizeof(dirty_expire_interval),
 866                 .mode           = 0644,
 867                 .proc_handler   = &proc_dointvec_userhz_jiffies,
 868         },
 869         {
 870                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
 871                 .procname       = "nr_pdflush_threads",
 872                 .data           = &nr_pdflush_threads,
 873                 .maxlen         = sizeof nr_pdflush_threads,
 874                 .mode           = 0444 /* read-only*/,
 875                 .proc_handler   = &proc_dointvec,
 876         },
 877         {
 878                 .ctl_name       = VM_SWAPPINESS,
 879                 .procname       = "swappiness",
 880                 .data           = &vm_swappiness,
 881                 .maxlen         = sizeof(vm_swappiness),
 882                 .mode           = 0644,
 883                 .proc_handler   = &proc_dointvec_minmax,
 884                 .strategy       = &sysctl_intvec,
 885                 .extra1         = &zero,
 886                 .extra2         = &one_hundred,
 887         },
 888 #ifdef CONFIG_HUGETLB_PAGE
 889          {
 890                 .ctl_name       = VM_HUGETLB_PAGES,
 891                 .procname       = "nr_hugepages",
 892                 .data           = &max_huge_pages,
 893                 .maxlen         = sizeof(unsigned long),
 894                 .mode           = 0644,
 895                 .proc_handler   = &hugetlb_sysctl_handler,
 896                 .extra1         = (void *)&hugetlb_zero,
 897                 .extra2         = (void *)&hugetlb_infinity,
 898          },
 899          {
 900                 .ctl_name       = VM_HUGETLB_GROUP,
 901                 .procname       = "hugetlb_shm_group",
 902                 .data           = &sysctl_hugetlb_shm_group,
 903                 .maxlen         = sizeof(gid_t),
 904                 .mode           = 0644,
 905                 .proc_handler   = &proc_dointvec,
 906          },
 907 #endif
 908         {
 909                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
 910                 .procname       = "lowmem_reserve_ratio",
 911                 .data           = &sysctl_lowmem_reserve_ratio,
 912                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
 913                 .mode           = 0644,
 914                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
 915                 .strategy       = &sysctl_intvec,
 916         },
 917         {
 918                 .ctl_name       = VM_DROP_PAGECACHE,
 919                 .procname       = "drop_caches",
 920                 .data           = &sysctl_drop_caches,
 921                 .maxlen         = sizeof(int),
 922                 .mode           = 0644,
 923                 .proc_handler   = drop_caches_sysctl_handler,
 924                 .strategy       = &sysctl_intvec,
 925         },
 926         {
 927                 .ctl_name       = VM_MIN_FREE_KBYTES,
 928                 .procname       = "min_free_kbytes",
 929                 .data           = &min_free_kbytes,
 930                 .maxlen         = sizeof(min_free_kbytes),
 931                 .mode           = 0644,
 932                 .proc_handler   = &min_free_kbytes_sysctl_handler,
 933                 .strategy       = &sysctl_intvec,
 934                 .extra1         = &zero,
 935         },
 936         {
 937                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
 938                 .procname       = "percpu_pagelist_fraction",
 939                 .data           = &percpu_pagelist_fraction,
 940                 .maxlen         = sizeof(percpu_pagelist_fraction),
 941                 .mode           = 0644,
 942                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
 943                 .strategy       = &sysctl_intvec,
 944                 .extra1         = &min_percpu_pagelist_fract,
 945         },
 946 #ifdef CONFIG_MMU
 947         {
 948                 .ctl_name       = VM_MAX_MAP_COUNT,
 949                 .procname       = "max_map_count",
 950                 .data           = &sysctl_max_map_count,
 951                 .maxlen         = sizeof(sysctl_max_map_count),
 952                 .mode           = 0644,
 953                 .proc_handler   = &proc_dointvec
 954         },
 955 #endif
 956         {
 957                 .ctl_name       = VM_LAPTOP_MODE,
 958                 .procname       = "laptop_mode",
 959                 .data           = &laptop_mode,
 960                 .maxlen         = sizeof(laptop_mode),
 961                 .mode           = 0644,
 962                 .proc_handler   = &proc_dointvec_jiffies,
 963                 .strategy       = &sysctl_jiffies,
 964         },
 965         {
 966                 .ctl_name       = VM_BLOCK_DUMP,
 967                 .procname       = "block_dump",
 968                 .data           = &block_dump,
 969                 .maxlen         = sizeof(block_dump),
 970                 .mode           = 0644,
 971                 .proc_handler   = &proc_dointvec,
 972                 .strategy       = &sysctl_intvec,
 973                 .extra1         = &zero,
 974         },
 975         {
 976                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
 977                 .procname       = "vfs_cache_pressure",
 978                 .data           = &sysctl_vfs_cache_pressure,
 979                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
 980                 .mode           = 0644,
 981                 .proc_handler   = &proc_dointvec,
 982                 .strategy       = &sysctl_intvec,
 983                 .extra1         = &zero,
 984         },
 985 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
 986         {
 987                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
 988                 .procname       = "legacy_va_layout",
 989                 .data           = &sysctl_legacy_va_layout,
 990                 .maxlen         = sizeof(sysctl_legacy_va_layout),
 991                 .mode           = 0644,
 992                 .proc_handler   = &proc_dointvec,
 993                 .strategy       = &sysctl_intvec,
 994                 .extra1         = &zero,
 995         },
 996 #endif
 997 #ifdef CONFIG_NUMA
 998         {
 999                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
1000                 .procname       = "zone_reclaim_mode",
1001                 .data           = &zone_reclaim_mode,
1002                 .maxlen         = sizeof(zone_reclaim_mode),
1003                 .mode           = 0644,
1004                 .proc_handler   = &proc_dointvec,
1005                 .strategy       = &sysctl_intvec,
1006                 .extra1         = &zero,
1007         },
1008         {
1009                 .ctl_name       = VM_MIN_UNMAPPED,
1010                 .procname       = "min_unmapped_ratio",
1011                 .data           = &sysctl_min_unmapped_ratio,
1012                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1013                 .mode           = 0644,
1014                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1015                 .strategy       = &sysctl_intvec,
1016                 .extra1         = &zero,
1017                 .extra2         = &one_hundred,
1018         },
1019         {
1020                 .ctl_name       = VM_MIN_SLAB,
1021                 .procname       = "min_slab_ratio",
1022                 .data           = &sysctl_min_slab_ratio,
1023                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1024                 .mode           = 0644,
1025                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1026                 .strategy       = &sysctl_intvec,
1027                 .extra1         = &zero,
1028                 .extra2         = &one_hundred,
1029         },
1030 #endif
1031 #ifdef CONFIG_X86_32
1032         {
1033                 .ctl_name       = VM_VDSO_ENABLED,
1034                 .procname       = "vdso_enabled",
1035                 .data           = &vdso_enabled,
1036                 .maxlen         = sizeof(vdso_enabled),
1037                 .mode           = 0644,
1038                 .proc_handler   = &proc_dointvec,
1039                 .strategy       = &sysctl_intvec,
1040                 .extra1         = &zero,
1041         },
1042 #endif
1043         { .ctl_name = 0 }
1044 };
1045
1046 static ctl_table fs_table[] = {
1047         {
1048                 .ctl_name       = FS_NRINODE,
1049                 .procname       = "inode-nr",
1050                 .data           = &inodes_stat,
1051                 .maxlen         = 2*sizeof(int),
1052                 .mode           = 0444,
1053                 .proc_handler   = &proc_dointvec,
1054         },
1055         {
1056                 .ctl_name       = FS_STATINODE,
1057                 .procname       = "inode-state",
1058                 .data           = &inodes_stat,
1059                 .maxlen         = 7*sizeof(int),
1060                 .mode           = 0444,
1061                 .proc_handler   = &proc_dointvec,
1062         },
1063         {
1064                 .ctl_name       = FS_NRFILE,
1065                 .procname       = "file-nr",
1066                 .data           = &files_stat,
1067                 .maxlen         = 3*sizeof(int),
1068                 .mode           = 0444,
1069                 .proc_handler   = &proc_nr_files,
1070         },
1071         {
1072                 .ctl_name       = FS_MAXFILE,
1073                 .procname       = "file-max",
1074                 .data           = &files_stat.max_files,
1075                 .maxlen         = sizeof(int),
1076                 .mode           = 0644,
1077                 .proc_handler   = &proc_dointvec,
1078         },
1079         {
1080                 .ctl_name       = FS_DENTRY,
1081                 .procname       = "dentry-state",
1082                 .data           = &dentry_stat,
1083                 .maxlen         = 6*sizeof(int),
1084                 .mode           = 0444,
1085                 .proc_handler   = &proc_dointvec,
1086         },
1087         {
1088                 .ctl_name       = FS_OVERFLOWUID,
1089                 .procname       = "overflowuid",
1090                 .data           = &fs_overflowuid,
1091                 .maxlen         = sizeof(int),
1092                 .mode           = 0644,
1093                 .proc_handler   = &proc_dointvec_minmax,
1094                 .strategy       = &sysctl_intvec,
1095                 .extra1         = &minolduid,
1096                 .extra2         = &maxolduid,
1097         },
1098         {
1099                 .ctl_name       = FS_OVERFLOWGID,
1100                 .procname       = "overflowgid",
1101                 .data           = &fs_overflowgid,
1102                 .maxlen         = sizeof(int),
1103                 .mode           = 0644,
1104                 .proc_handler   = &proc_dointvec_minmax,
1105                 .strategy       = &sysctl_intvec,
1106                 .extra1         = &minolduid,
1107                 .extra2         = &maxolduid,
1108         },
1109         {
1110                 .ctl_name       = FS_LEASES,
1111                 .procname       = "leases-enable",
1112                 .data           = &leases_enable,
1113                 .maxlen         = sizeof(int),
1114                 .mode           = 0644,
1115                 .proc_handler   = &proc_dointvec,
1116         },
1117 #ifdef CONFIG_DNOTIFY
1118         {
1119                 .ctl_name       = FS_DIR_NOTIFY,
1120                 .procname       = "dir-notify-enable",
1121                 .data           = &dir_notify_enable,
1122                 .maxlen         = sizeof(int),
1123                 .mode           = 0644,
1124                 .proc_handler   = &proc_dointvec,
1125         },
1126 #endif
1127 #ifdef CONFIG_MMU
1128         {
1129                 .ctl_name       = FS_LEASE_TIME,
1130                 .procname       = "lease-break-time",
1131                 .data           = &lease_break_time,
1132                 .maxlen         = sizeof(int),
1133                 .mode           = 0644,
1134                 .proc_handler   = &proc_dointvec,
1135         },
1136         {
1137                 .ctl_name       = FS_AIO_NR,
1138                 .procname       = "aio-nr",
1139                 .data           = &aio_nr,
1140                 .maxlen         = sizeof(aio_nr),
1141                 .mode           = 0444,
1142                 .proc_handler   = &proc_doulongvec_minmax,
1143         },
1144         {
1145                 .ctl_name       = FS_AIO_MAX_NR,
1146                 .procname       = "aio-max-nr",
1147                 .data           = &aio_max_nr,
1148                 .maxlen         = sizeof(aio_max_nr),
1149                 .mode           = 0644,
1150                 .proc_handler   = &proc_doulongvec_minmax,
1151         },
1152 #ifdef CONFIG_INOTIFY_USER
1153         {
1154                 .ctl_name       = FS_INOTIFY,
1155                 .procname       = "inotify",
1156                 .mode           = 0555,
1157                 .child          = inotify_table,
1158         },
1159 #endif
1160 #endif
1161         {
1162                 .ctl_name       = KERN_SETUID_DUMPABLE,
1163                 .procname       = "suid_dumpable",
1164                 .data           = &suid_dumpable,
1165                 .maxlen         = sizeof(int),
1166                 .mode           = 0644,
1167                 .proc_handler   = &proc_dointvec,
1168         },
1169         { .ctl_name = 0 }
1170 };
1171
1172 static ctl_table debug_table[] = {
1173         { .ctl_name = 0 }
1174 };
1175
1176 static ctl_table dev_table[] = {
1177         { .ctl_name = 0 }
1178 };
1179
1180 extern void init_irq_proc (void);
1181
1182 static DEFINE_SPINLOCK(sysctl_lock);
1183
1184 /* called under sysctl_lock */
1185 static int use_table(struct ctl_table_header *p)
1186 {
1187         if (unlikely(p->unregistering))
1188                 return 0;
1189         p->used++;
1190         return 1;
1191 }
1192
1193 /* called under sysctl_lock */
1194 static void unuse_table(struct ctl_table_header *p)
1195 {
1196         if (!--p->used)
1197                 if (unlikely(p->unregistering))
1198                         complete(p->unregistering);
1199 }
1200
1201 /* called under sysctl_lock, will reacquire if has to wait */
1202 static void start_unregistering(struct ctl_table_header *p)
1203 {
1204         /*
1205          * if p->used is 0, nobody will ever touch that entry again;
1206          * we'll eliminate all paths to it before dropping sysctl_lock
1207          */
1208         if (unlikely(p->used)) {
1209                 struct completion wait;
1210                 init_completion(&wait);
1211                 p->unregistering = &wait;
1212                 spin_unlock(&sysctl_lock);
1213                 wait_for_completion(&wait);
1214                 spin_lock(&sysctl_lock);
1215         }
1216         /*
1217          * do not remove from the list until nobody holds it; walking the
1218          * list in do_sysctl() relies on that.
1219          */
1220         list_del_init(&p->ctl_entry);
1221 }
1222
1223 void __init sysctl_init(void)
1224 {
1225 #ifdef CONFIG_PROC_SYSCTL
1226         register_proc_table(root_table, proc_sys_root, &root_table_header);
1227         init_irq_proc();
1228 #endif
1229 }
1230
1231 #ifdef CONFIG_SYSCTL_SYSCALL
1232 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1233                void __user *newval, size_t newlen)
1234 {
1235         struct list_head *tmp;
1236         int error = -ENOTDIR;
1237
1238         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1239                 return -ENOTDIR;
1240         if (oldval) {
1241                 int old_len;
1242                 if (!oldlenp || get_user(old_len, oldlenp))
1243                         return -EFAULT;
1244         }
1245         spin_lock(&sysctl_lock);
1246         tmp = &root_table_header.ctl_entry;
1247         do {
1248                 struct ctl_table_header *head =
1249                         list_entry(tmp, struct ctl_table_header, ctl_entry);
1250
1251                 if (!use_table(head))
1252                         continue;
1253
1254                 spin_unlock(&sysctl_lock);
1255
1256                 error = parse_table(name, nlen, oldval, oldlenp,
1257                                         newval, newlen, head->ctl_table);
1258
1259                 spin_lock(&sysctl_lock);
1260                 unuse_table(head);
1261                 if (error != -ENOTDIR)
1262                         break;
1263         } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1264         spin_unlock(&sysctl_lock);
1265         return error;
1266 }
1267
1268 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1269 {
1270         struct __sysctl_args tmp;
1271         int error;
1272
1273         if (copy_from_user(&tmp, args, sizeof(tmp)))
1274                 return -EFAULT;
1275
1276         lock_kernel();
1277         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1278                           tmp.newval, tmp.newlen);
1279         unlock_kernel();
1280         return error;
1281 }
1282 #endif /* CONFIG_SYSCTL_SYSCALL */
1283
1284 /*
1285  * ctl_perm does NOT grant the superuser all rights automatically, because
1286  * some sysctl variables are readonly even to root.
1287  */
1288
1289 static int test_perm(int mode, int op)
1290 {
1291         if (!current->euid)
1292                 mode >>= 6;
1293         else if (in_egroup_p(0))
1294                 mode >>= 3;
1295         if ((mode & op & 0007) == op)
1296                 return 0;
1297         return -EACCES;
1298 }
1299
1300 static inline int ctl_perm(ctl_table *table, int op)
1301 {
1302         int error;
1303         error = security_sysctl(table, op);
1304         if (error)
1305                 return error;
1306         return test_perm(table->mode, op);
1307 }
1308
1309 #ifdef CONFIG_SYSCTL_SYSCALL
1310 static int parse_table(int __user *name, int nlen,
1311                        void __user *oldval, size_t __user *oldlenp,
1312                        void __user *newval, size_t newlen,
1313                        ctl_table *table)
1314 {
1315         int n;
1316 repeat:
1317         if (!nlen)
1318                 return -ENOTDIR;
1319         if (get_user(n, name))
1320                 return -EFAULT;
1321         for ( ; table->ctl_name || table->procname; table++) {
1322                 if (!table->ctl_name)
1323                         continue;
1324                 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1325                         int error;
1326                         if (table->child) {
1327                                 if (ctl_perm(table, 001))
1328                                         return -EPERM;
1329                                 if (table->strategy) {
1330                                         error = table->strategy(
1331                                                 table, name, nlen,
1332                                                 oldval, oldlenp,
1333                                                 newval, newlen);
1334                                         if (error)
1335                                                 return error;
1336                                 }
1337                                 name++;
1338                                 nlen--;
1339                                 table = table->child;
1340                                 goto repeat;
1341                         }
1342                         error = do_sysctl_strategy(table, name, nlen,
1343                                                    oldval, oldlenp,
1344                                                    newval, newlen);
1345                         return error;
1346                 }
1347         }
1348         return -ENOTDIR;
1349 }
1350
1351 /* Perform the actual read/write of a sysctl table entry. */
1352 int do_sysctl_strategy (ctl_table *table,
1353                         int __user *name, int nlen,
1354                         void __user *oldval, size_t __user *oldlenp,
1355                         void __user *newval, size_t newlen)
1356 {
1357         int op = 0, rc;
1358         size_t len;
1359
1360         if (oldval)
1361                 op |= 004;
1362         if (newval)
1363                 op |= 002;
1364         if (ctl_perm(table, op))
1365                 return -EPERM;
1366
1367         if (table->strategy) {
1368                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1369                                      newval, newlen);
1370                 if (rc < 0)
1371                         return rc;
1372                 if (rc > 0)
1373                         return 0;
1374         }
1375
1376         /* If there is no strategy routine, or if the strategy returns
1377          * zero, proceed with automatic r/w */
1378         if (table->data && table->maxlen) {
1379                 if (oldval && oldlenp) {
1380                         if (get_user(len, oldlenp))
1381                                 return -EFAULT;
1382                         if (len) {
1383                                 if (len > table->maxlen)
1384                                         len = table->maxlen;
1385                                 if(copy_to_user(oldval, table->data, len))
1386                                         return -EFAULT;
1387                                 if(put_user(len, oldlenp))
1388                                         return -EFAULT;
1389                         }
1390                 }
1391                 if (newval && newlen) {
1392                         len = newlen;
1393                         if (len > table->maxlen)
1394                                 len = table->maxlen;
1395                         if(copy_from_user(table->data, newval, len))
1396                                 return -EFAULT;
1397                 }
1398         }
1399         return 0;
1400 }
1401 #endif /* CONFIG_SYSCTL_SYSCALL */
1402
1403 /**
1404  * register_sysctl_table - register a sysctl hierarchy
1405  * @table: the top-level table structure
1406  * @insert_at_head: whether the entry should be inserted in front or at the end
1407  *
1408  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1409  * array. An entry with a ctl_name of 0 terminates the table.
1410  *
1411  * The members of the &ctl_table structure are used as follows:
1412  *
1413  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1414  *            must be unique within that level of sysctl
1415  *
1416  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1417  *            enter a sysctl file
1418  *
1419  * data - a pointer to data for use by proc_handler
1420  *
1421  * maxlen - the maximum size in bytes of the data
1422  *
1423  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1424  *
1425  * child - a pointer to the child sysctl table if this entry is a directory, or
1426  *         %NULL.
1427  *
1428  * proc_handler - the text handler routine (described below)
1429  *
1430  * strategy - the strategy routine (described below)
1431  *
1432  * de - for internal use by the sysctl routines
1433  *
1434  * extra1, extra2 - extra pointers usable by the proc handler routines
1435  *
1436  * Leaf nodes in the sysctl tree will be represented by a single file
1437  * under /proc; non-leaf nodes will be represented by directories.
1438  *
1439  * sysctl(2) can automatically manage read and write requests through
1440  * the sysctl table.  The data and maxlen fields of the ctl_table
1441  * struct enable minimal validation of the values being written to be
1442  * performed, and the mode field allows minimal authentication.
1443  *
1444  * More sophisticated management can be enabled by the provision of a
1445  * strategy routine with the table entry.  This will be called before
1446  * any automatic read or write of the data is performed.
1447  *
1448  * The strategy routine may return
1449  *
1450  * < 0 - Error occurred (error is passed to user process)
1451  *
1452  * 0   - OK - proceed with automatic read or write.
1453  *
1454  * > 0 - OK - read or write has been done by the strategy routine, so
1455  *       return immediately.
1456  *
1457  * There must be a proc_handler routine for any terminal nodes
1458  * mirrored under /proc/sys (non-terminals are handled by a built-in
1459  * directory handler).  Several default handlers are available to
1460  * cover common cases -
1461  *
1462  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1463  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1464  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1465  *
1466  * It is the handler's job to read the input buffer from user memory
1467  * and process it. The handler should return 0 on success.
1468  *
1469  * This routine returns %NULL on a failure to register, and a pointer
1470  * to the table header on success.
1471  */
1472 struct ctl_table_header *register_sysctl_table(ctl_table * table,
1473                                                int insert_at_head)
1474 {
1475         struct ctl_table_header *tmp;
1476         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1477         if (!tmp)
1478                 return NULL;
1479         tmp->ctl_table = table;
1480         INIT_LIST_HEAD(&tmp->ctl_entry);
1481         tmp->used = 0;
1482         tmp->unregistering = NULL;
1483         spin_lock(&sysctl_lock);
1484         if (insert_at_head)
1485                 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1486         else
1487                 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1488         spin_unlock(&sysctl_lock);
1489 #ifdef CONFIG_PROC_SYSCTL
1490         register_proc_table(table, proc_sys_root, tmp);
1491 #endif
1492         return tmp;
1493 }
1494
1495 /**
1496  * unregister_sysctl_table - unregister a sysctl table hierarchy
1497  * @header: the header returned from register_sysctl_table
1498  *
1499  * Unregisters the sysctl table and all children. proc entries may not
1500  * actually be removed until they are no longer used by anyone.
1501  */
1502 void unregister_sysctl_table(struct ctl_table_header * header)
1503 {
1504         might_sleep();
1505         spin_lock(&sysctl_lock);
1506         start_unregistering(header);
1507 #ifdef CONFIG_PROC_SYSCTL
1508         unregister_proc_table(header->ctl_table, proc_sys_root);
1509 #endif
1510         spin_unlock(&sysctl_lock);
1511         kfree(header);
1512 }
1513
1514 #else /* !CONFIG_SYSCTL */
1515 struct ctl_table_header * register_sysctl_table(ctl_table * table,
1516                                                 int insert_at_head)
1517 {
1518         return NULL;
1519 }
1520
1521 void unregister_sysctl_table(struct ctl_table_header * table)
1522 {
1523 }
1524
1525 #endif /* CONFIG_SYSCTL */
1526
1527 /*
1528  * /proc/sys support
1529  */
1530
1531 #ifdef CONFIG_PROC_SYSCTL
1532
1533 /* Scan the sysctl entries in table and add them all into /proc */
1534 static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1535 {
1536         struct proc_dir_entry *de;
1537         int len;
1538         mode_t mode;
1539
1540         for (; table->ctl_name || table->procname; table++) {
1541                 /* Can't do anything without a proc name. */
1542                 if (!table->procname)
1543                         continue;
1544                 /* Maybe we can't do anything with it... */
1545                 if (!table->proc_handler && !table->child) {
1546                         printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1547                                 table->procname);
1548                         continue;
1549                 }
1550
1551                 len = strlen(table->procname);
1552                 mode = table->mode;
1553
1554                 de = NULL;
1555                 if (table->proc_handler)
1556                         mode |= S_IFREG;
1557                 else {
1558                         mode |= S_IFDIR;
1559                         for (de = root->subdir; de; de = de->next) {
1560                                 if (proc_match(len, table->procname, de))
1561                                         break;
1562                         }
1563                         /* If the subdir exists already, de is non-NULL */
1564                 }
1565
1566                 if (!de) {
1567                         de = create_proc_entry(table->procname, mode, root);
1568                         if (!de)
1569                                 continue;
1570                         de->set = set;
1571                         de->data = (void *) table;
1572                         if (table->proc_handler)
1573                                 de->proc_fops = &proc_sys_file_operations;
1574                 }
1575                 table->de = de;
1576                 if (de->mode & S_IFDIR)
1577                         register_proc_table(table->child, de, set);
1578         }
1579 }
1580
1581 /*
1582  * Unregister a /proc sysctl table and any subdirectories.
1583  */
1584 static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1585 {
1586         struct proc_dir_entry *de;
1587         for (; table->ctl_name || table->procname; table++) {
1588                 if (!(de = table->de))
1589                         continue;
1590                 if (de->mode & S_IFDIR) {
1591                         if (!table->child) {
1592                                 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1593                                 continue;
1594                         }
1595                         unregister_proc_table(table->child, de);
1596
1597                         /* Don't unregister directories which still have entries.. */
1598                         if (de->subdir)
1599                                 continue;
1600                 }
1601
1602                 /*
1603                  * In any case, mark the entry as goner; we'll keep it
1604                  * around if it's busy, but we'll know to do nothing with
1605                  * its fields.  We are under sysctl_lock here.
1606                  */
1607                 de->data = NULL;
1608
1609                 /* Don't unregister proc entries that are still being used.. */
1610                 if (atomic_read(&de->count))
1611                         continue;
1612
1613                 table->de = NULL;
1614                 remove_proc_entry(table->procname, root);
1615         }
1616 }
1617
1618 static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1619                           size_t count, loff_t *ppos)
1620 {
1621         int op;
1622         struct proc_dir_entry *de = PDE(file->f_path.dentry->d_inode);
1623         struct ctl_table *table;
1624         size_t res;
1625         ssize_t error = -ENOTDIR;
1626
1627         spin_lock(&sysctl_lock);
1628         if (de && de->data && use_table(de->set)) {
1629                 /*
1630                  * at that point we know that sysctl was not unregistered
1631                  * and won't be until we finish
1632                  */
1633                 spin_unlock(&sysctl_lock);
1634                 table = (struct ctl_table *) de->data;
1635                 if (!table || !table->proc_handler)
1636                         goto out;
1637                 error = -EPERM;
1638                 op = (write ? 002 : 004);
1639                 if (ctl_perm(table, op))
1640                         goto out;
1641
1642                 /* careful: calling conventions are nasty here */
1643                 res = count;
1644                 error = (*table->proc_handler)(table, write, file,
1645                                                 buf, &res, ppos);
1646                 if (!error)
1647                         error = res;
1648         out:
1649                 spin_lock(&sysctl_lock);
1650                 unuse_table(de->set);
1651         }
1652         spin_unlock(&sysctl_lock);
1653         return error;
1654 }
1655
1656 static int proc_opensys(struct inode *inode, struct file *file)
1657 {
1658         if (file->f_mode & FMODE_WRITE) {
1659                 /*
1660                  * sysctl entries that are not writable,
1661                  * are _NOT_ writable, capabilities or not.
1662                  */
1663                 if (!(inode->i_mode & S_IWUSR))
1664                         return -EPERM;
1665         }
1666
1667         return 0;
1668 }
1669
1670 static ssize_t proc_readsys(struct file * file, char __user * buf,
1671                             size_t count, loff_t *ppos)
1672 {
1673         return do_rw_proc(0, file, buf, count, ppos);
1674 }
1675
1676 static ssize_t proc_writesys(struct file * file, const char __user * buf,
1677                              size_t count, loff_t *ppos)
1678 {
1679         return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1680 }
1681
1682 static int _proc_do_string(void* data, int maxlen, int write,
1683                            struct file *filp, void __user *buffer,
1684                            size_t *lenp, loff_t *ppos)
1685 {
1686         size_t len;
1687         char __user *p;
1688         char c;
1689
1690         if (!data || !maxlen || !*lenp) {
1691                 *lenp = 0;
1692                 return 0;
1693         }
1694
1695         if (write) {
1696                 len = 0;
1697                 p = buffer;
1698                 while (len < *lenp) {
1699                         if (get_user(c, p++))
1700                                 return -EFAULT;
1701                         if (c == 0 || c == '\n')
1702                                 break;
1703                         len++;
1704                 }
1705                 if (len >= maxlen)
1706                         len = maxlen-1;
1707                 if(copy_from_user(data, buffer, len))
1708                         return -EFAULT;
1709                 ((char *) data)[len] = 0;
1710                 *ppos += *lenp;
1711         } else {
1712                 len = strlen(data);
1713                 if (len > maxlen)
1714                         len = maxlen;
1715
1716                 if (*ppos > len) {
1717                         *lenp = 0;
1718                         return 0;
1719                 }
1720
1721                 data += *ppos;
1722                 len  -= *ppos;
1723
1724                 if (len > *lenp)
1725                         len = *lenp;
1726                 if (len)
1727                         if(copy_to_user(buffer, data, len))
1728                                 return -EFAULT;
1729                 if (len < *lenp) {
1730                         if(put_user('\n', ((char __user *) buffer) + len))
1731                                 return -EFAULT;
1732                         len++;
1733                 }
1734                 *lenp = len;
1735                 *ppos += len;
1736         }
1737         return 0;
1738 }
1739
1740 /**
1741  * proc_dostring - read a string sysctl
1742  * @table: the sysctl table
1743  * @write: %TRUE if this is a write to the sysctl file
1744  * @filp: the file structure
1745  * @buffer: the user buffer
1746  * @lenp: the size of the user buffer
1747  * @ppos: file position
1748  *
1749  * Reads/writes a string from/to the user buffer. If the kernel
1750  * buffer provided is not large enough to hold the string, the
1751  * string is truncated. The copied string is %NULL-terminated.
1752  * If the string is being read by the user process, it is copied
1753  * and a newline '\n' is added. It is truncated if the buffer is
1754  * not large enough.
1755  *
1756  * Returns 0 on success.
1757  */
1758 int proc_dostring(ctl_table *table, int write, struct file *filp,
1759                   void __user *buffer, size_t *lenp, loff_t *ppos)
1760 {
1761         return _proc_do_string(table->data, table->maxlen, write, filp,
1762                                buffer, lenp, ppos);
1763 }
1764
1765 /*
1766  *      Special case of dostring for the UTS structure. This has locks
1767  *      to observe. Should this be in kernel/sys.c ????
1768  */
1769
1770 static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
1771                   void __user *buffer, size_t *lenp, loff_t *ppos)
1772 {
1773         int r;
1774         void *which;
1775         which = get_uts(table, write);
1776         r = _proc_do_string(which, table->maxlen,write,filp,buffer,lenp, ppos);
1777         put_uts(table, write, which);
1778         return r;
1779 }
1780
1781 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1782                                  int *valp,
1783                                  int write, void *data)
1784 {
1785         if (write) {
1786                 *valp = *negp ? -*lvalp : *lvalp;
1787         } else {
1788                 int val = *valp;
1789                 if (val < 0) {
1790                         *negp = -1;
1791                         *lvalp = (unsigned long)-val;
1792                 } else {
1793                         *negp = 0;
1794                         *lvalp = (unsigned long)val;
1795                 }
1796         }
1797         return 0;
1798 }
1799
1800 static int __do_proc_dointvec(void *tbl_data, ctl_table *table,
1801                   int write, struct file *filp, void __user *buffer,
1802                   size_t *lenp, loff_t *ppos,
1803                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1804                               int write, void *data),
1805                   void *data)
1806 {
1807 #define TMPBUFLEN 21
1808         int *i, vleft, first=1, neg, val;
1809         unsigned long lval;
1810         size_t left, len;
1811
1812         char buf[TMPBUFLEN], *p;
1813         char __user *s = buffer;
1814
1815         if (!tbl_data || !table->maxlen || !*lenp ||
1816             (*ppos && !write)) {
1817                 *lenp = 0;
1818                 return 0;
1819         }
1820
1821         i = (int *) tbl_data;
1822         vleft = table->maxlen / sizeof(*i);
1823         left = *lenp;
1824
1825         if (!conv)
1826                 conv = do_proc_dointvec_conv;
1827
1828         for (; left && vleft--; i++, first=0) {
1829                 if (write) {
1830                         while (left) {
1831                                 char c;
1832                                 if (get_user(c, s))
1833                                         return -EFAULT;
1834                                 if (!isspace(c))
1835                                         break;
1836                                 left--;
1837                                 s++;
1838                         }
1839                         if (!left)
1840                                 break;
1841                         neg = 0;
1842                         len = left;
1843                         if (len > sizeof(buf) - 1)
1844                                 len = sizeof(buf) - 1;
1845                         if (copy_from_user(buf, s, len))
1846                                 return -EFAULT;
1847                         buf[len] = 0;
1848                         p = buf;
1849                         if (*p == '-' && left > 1) {
1850                                 neg = 1;
1851                                 p++;
1852                         }
1853                         if (*p < '0' || *p > '9')
1854                                 break;
1855
1856                         lval = simple_strtoul(p, &p, 0);
1857
1858                         len = p-buf;
1859                         if ((len < left) && *p && !isspace(*p))
1860                                 break;
1861                         if (neg)
1862                                 val = -val;
1863                         s += len;
1864                         left -= len;
1865
1866                         if (conv(&neg, &lval, i, 1, data))
1867                                 break;
1868                 } else {
1869                         p = buf;
1870                         if (!first)
1871                                 *p++ = '\t';
1872
1873                         if (conv(&neg, &lval, i, 0, data))
1874                                 break;
1875
1876                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1877                         len = strlen(buf);
1878                         if (len > left)
1879                                 len = left;
1880                         if(copy_to_user(s, buf, len))
1881                                 return -EFAULT;
1882                         left -= len;
1883                         s += len;
1884                 }
1885         }
1886
1887         if (!write && !first && left) {
1888                 if(put_user('\n', s))
1889                         return -EFAULT;
1890                 left--, s++;
1891         }
1892         if (write) {
1893                 while (left) {
1894                         char c;
1895                         if (get_user(c, s++))
1896                                 return -EFAULT;
1897                         if (!isspace(c))
1898                                 break;
1899                         left--;
1900                 }
1901         }
1902         if (write && first)
1903                 return -EINVAL;
1904         *lenp -= left;
1905         *ppos += *lenp;
1906         return 0;
1907 #undef TMPBUFLEN
1908 }
1909
1910 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1911                   void __user *buffer, size_t *lenp, loff_t *ppos,
1912                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1913                               int write, void *data),
1914                   void *data)
1915 {
1916         return __do_proc_dointvec(table->data, table, write, filp,
1917                         buffer, lenp, ppos, conv, data);
1918 }
1919
1920 /**
1921  * proc_dointvec - read a vector of integers
1922  * @table: the sysctl table
1923  * @write: %TRUE if this is a write to the sysctl file
1924  * @filp: the file structure
1925  * @buffer: the user buffer
1926  * @lenp: the size of the user buffer
1927  * @ppos: file position
1928  *
1929  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1930  * values from/to the user buffer, treated as an ASCII string.
1931  *
1932  * Returns 0 on success.
1933  */
1934 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1935                      void __user *buffer, size_t *lenp, loff_t *ppos)
1936 {
1937     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1938                             NULL,NULL);
1939 }
1940
1941 #define OP_SET  0
1942 #define OP_AND  1
1943 #define OP_OR   2
1944
1945 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1946                                       int *valp,
1947                                       int write, void *data)
1948 {
1949         int op = *(int *)data;
1950         if (write) {
1951                 int val = *negp ? -*lvalp : *lvalp;
1952                 switch(op) {
1953                 case OP_SET:    *valp = val; break;
1954                 case OP_AND:    *valp &= val; break;
1955                 case OP_OR:     *valp |= val; break;
1956                 }
1957         } else {
1958                 int val = *valp;
1959                 if (val < 0) {
1960                         *negp = -1;
1961                         *lvalp = (unsigned long)-val;
1962                 } else {
1963                         *negp = 0;
1964                         *lvalp = (unsigned long)val;
1965                 }
1966         }
1967         return 0;
1968 }
1969
1970 /*
1971  *      init may raise the set.
1972  */
1973
1974 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1975                         void __user *buffer, size_t *lenp, loff_t *ppos)
1976 {
1977         int op;
1978
1979         if (write && !capable(CAP_SYS_MODULE)) {
1980                 return -EPERM;
1981         }
1982
1983         op = is_init(current) ? OP_SET : OP_AND;
1984         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1985                                 do_proc_dointvec_bset_conv,&op);
1986 }
1987
1988 /*
1989  *      Taint values can only be increased
1990  */
1991 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
1992                                void __user *buffer, size_t *lenp, loff_t *ppos)
1993 {
1994         int op;
1995
1996         if (!capable(CAP_SYS_ADMIN))
1997                 return -EPERM;
1998
1999         op = OP_OR;
2000         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2001                                 do_proc_dointvec_bset_conv,&op);
2002 }
2003
2004 struct do_proc_dointvec_minmax_conv_param {
2005         int *min;
2006         int *max;
2007 };
2008
2009 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2010                                         int *valp,
2011                                         int write, void *data)
2012 {
2013         struct do_proc_dointvec_minmax_conv_param *param = data;
2014         if (write) {
2015                 int val = *negp ? -*lvalp : *lvalp;
2016                 if ((param->min && *param->min > val) ||
2017                     (param->max && *param->max < val))
2018                         return -EINVAL;
2019                 *valp = val;
2020         } else {
2021                 int val = *valp;
2022                 if (val < 0) {
2023                         *negp = -1;
2024                         *lvalp = (unsigned long)-val;
2025                 } else {
2026                         *negp = 0;
2027                         *lvalp = (unsigned long)val;
2028                 }
2029         }
2030         return 0;
2031 }
2032
2033 /**
2034  * proc_dointvec_minmax - read a vector of integers with min/max values
2035  * @table: the sysctl table
2036  * @write: %TRUE if this is a write to the sysctl file
2037  * @filp: the file structure
2038  * @buffer: the user buffer
2039  * @lenp: the size of the user buffer
2040  * @ppos: file position
2041  *
2042  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2043  * values from/to the user buffer, treated as an ASCII string.
2044  *
2045  * This routine will ensure the values are within the range specified by
2046  * table->extra1 (min) and table->extra2 (max).
2047  *
2048  * Returns 0 on success.
2049  */
2050 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2051                   void __user *buffer, size_t *lenp, loff_t *ppos)
2052 {
2053         struct do_proc_dointvec_minmax_conv_param param = {
2054                 .min = (int *) table->extra1,
2055                 .max = (int *) table->extra2,
2056         };
2057         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2058                                 do_proc_dointvec_minmax_conv, &param);
2059 }
2060
2061 static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
2062                                      struct file *filp,
2063                                      void __user *buffer,
2064                                      size_t *lenp, loff_t *ppos,
2065                                      unsigned long convmul,
2066                                      unsigned long convdiv)
2067 {
2068 #define TMPBUFLEN 21
2069         unsigned long *i, *min, *max, val;
2070         int vleft, first=1, neg;
2071         size_t len, left;
2072         char buf[TMPBUFLEN], *p;
2073         char __user *s = buffer;
2074
2075         if (!data || !table->maxlen || !*lenp ||
2076             (*ppos && !write)) {
2077                 *lenp = 0;
2078                 return 0;
2079         }
2080
2081         i = (unsigned long *) data;
2082         min = (unsigned long *) table->extra1;
2083         max = (unsigned long *) table->extra2;
2084         vleft = table->maxlen / sizeof(unsigned long);
2085         left = *lenp;
2086
2087         for (; left && vleft--; i++, min++, max++, first=0) {
2088                 if (write) {
2089                         while (left) {
2090                                 char c;
2091                                 if (get_user(c, s))
2092                                         return -EFAULT;
2093                                 if (!isspace(c))
2094                                         break;
2095                                 left--;
2096                                 s++;
2097                         }
2098                         if (!left)
2099                                 break;
2100                         neg = 0;
2101                         len = left;
2102                         if (len > TMPBUFLEN-1)
2103                                 len = TMPBUFLEN-1;
2104                         if (copy_from_user(buf, s, len))
2105                                 return -EFAULT;
2106                         buf[len] = 0;
2107                         p = buf;
2108                         if (*p == '-' && left > 1) {
2109                                 neg = 1;
2110                                 p++;
2111                         }
2112                         if (*p < '0' || *p > '9')
2113                                 break;
2114                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2115                         len = p-buf;
2116                         if ((len < left) && *p && !isspace(*p))
2117                                 break;
2118                         if (neg)
2119                                 val = -val;
2120                         s += len;
2121                         left -= len;
2122
2123                         if(neg)
2124                                 continue;
2125                         if ((min && val < *min) || (max && val > *max))
2126                                 continue;
2127                         *i = val;
2128                 } else {
2129                         p = buf;
2130                         if (!first)
2131                                 *p++ = '\t';
2132                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2133                         len = strlen(buf);
2134                         if (len > left)
2135                                 len = left;
2136                         if(copy_to_user(s, buf, len))
2137                                 return -EFAULT;
2138                         left -= len;
2139                         s += len;
2140                 }
2141         }
2142
2143         if (!write && !first && left) {
2144                 if(put_user('\n', s))
2145                         return -EFAULT;
2146                 left--, s++;
2147         }
2148         if (write) {
2149                 while (left) {
2150                         char c;
2151                         if (get_user(c, s++))
2152                                 return -EFAULT;
2153                         if (!isspace(c))
2154                                 break;
2155                         left--;
2156                 }
2157         }
2158         if (write && first)
2159                 return -EINVAL;
2160         *lenp -= left;
2161         *ppos += *lenp;
2162         return 0;
2163 #undef TMPBUFLEN
2164 }
2165
2166 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
2167                                      struct file *filp,
2168                                      void __user *buffer,
2169                                      size_t *lenp, loff_t *ppos,
2170                                      unsigned long convmul,
2171                                      unsigned long convdiv)
2172 {
2173         return __do_proc_doulongvec_minmax(table->data, table, write,
2174                         filp, buffer, lenp, ppos, convmul, convdiv);
2175 }
2176
2177 /**
2178  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2179  * @table: the sysctl table
2180  * @write: %TRUE if this is a write to the sysctl file
2181  * @filp: the file structure
2182  * @buffer: the user buffer
2183  * @lenp: the size of the user buffer
2184  * @ppos: file position
2185  *
2186  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2187  * values from/to the user buffer, treated as an ASCII string.
2188  *
2189  * This routine will ensure the values are within the range specified by
2190  * table->extra1 (min) and table->extra2 (max).
2191  *
2192  * Returns 0 on success.
2193  */
2194 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2195                            void __user *buffer, size_t *lenp, loff_t *ppos)
2196 {
2197     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2198 }
2199
2200 /**
2201  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2202  * @table: the sysctl table
2203  * @write: %TRUE if this is a write to the sysctl file
2204  * @filp: the file structure
2205  * @buffer: the user buffer
2206  * @lenp: the size of the user buffer
2207  * @ppos: file position
2208  *
2209  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2210  * values from/to the user buffer, treated as an ASCII string. The values
2211  * are treated as milliseconds, and converted to jiffies when they are stored.
2212  *
2213  * This routine will ensure the values are within the range specified by
2214  * table->extra1 (min) and table->extra2 (max).
2215  *
2216  * Returns 0 on success.
2217  */
2218 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2219                                       struct file *filp,
2220                                       void __user *buffer,
2221                                       size_t *lenp, loff_t *ppos)
2222 {
2223     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2224                                      lenp, ppos, HZ, 1000l);
2225 }
2226
2227
2228 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2229                                          int *valp,
2230                                          int write, void *data)
2231 {
2232         if (write) {
2233                 if (*lvalp > LONG_MAX / HZ)
2234                         return 1;
2235                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2236         } else {
2237                 int val = *valp;
2238                 unsigned long lval;
2239                 if (val < 0) {
2240                         *negp = -1;
2241                         lval = (unsigned long)-val;
2242                 } else {
2243                         *negp = 0;
2244                         lval = (unsigned long)val;
2245                 }
2246                 *lvalp = lval / HZ;
2247         }
2248         return 0;
2249 }
2250
2251 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2252                                                 int *valp,
2253                                                 int write, void *data)
2254 {
2255         if (write) {
2256                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2257                         return 1;
2258                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2259         } else {
2260                 int val = *valp;
2261                 unsigned long lval;
2262                 if (val < 0) {
2263                         *negp = -1;
2264                         lval = (unsigned long)-val;
2265                 } else {
2266                         *negp = 0;
2267                         lval = (unsigned long)val;
2268                 }
2269                 *lvalp = jiffies_to_clock_t(lval);
2270         }
2271         return 0;
2272 }
2273
2274 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2275                                             int *valp,
2276                                             int write, void *data)
2277 {
2278         if (write) {
2279                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2280         } else {
2281                 int val = *valp;
2282                 unsigned long lval;
2283                 if (val < 0) {
2284                         *negp = -1;
2285                         lval = (unsigned long)-val;
2286                 } else {
2287                         *negp = 0;
2288                         lval = (unsigned long)val;
2289                 }
2290                 *lvalp = jiffies_to_msecs(lval);
2291         }
2292         return 0;
2293 }
2294
2295 /**
2296  * proc_dointvec_jiffies - read a vector of integers as seconds
2297  * @table: the sysctl table
2298  * @write: %TRUE if this is a write to the sysctl file
2299  * @filp: the file structure
2300  * @buffer: the user buffer
2301  * @lenp: the size of the user buffer
2302  * @ppos: file position
2303  *
2304  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2305  * values from/to the user buffer, treated as an ASCII string.
2306  * The values read are assumed to be in seconds, and are converted into
2307  * jiffies.
2308  *
2309  * Returns 0 on success.
2310  */
2311 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2312                           void __user *buffer, size_t *lenp, loff_t *ppos)
2313 {
2314     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2315                             do_proc_dointvec_jiffies_conv,NULL);
2316 }
2317
2318 /**
2319  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2320  * @table: the sysctl table
2321  * @write: %TRUE if this is a write to the sysctl file
2322  * @filp: the file structure
2323  * @buffer: the user buffer
2324  * @lenp: the size of the user buffer
2325  * @ppos: pointer to the file position
2326  *
2327  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2328  * values from/to the user buffer, treated as an ASCII string.
2329  * The values read are assumed to be in 1/USER_HZ seconds, and
2330  * are converted into jiffies.
2331  *
2332  * Returns 0 on success.
2333  */
2334 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2335                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2336 {
2337     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2338                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2339 }
2340
2341 /**
2342  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2343  * @table: the sysctl table
2344  * @write: %TRUE if this is a write to the sysctl file
2345  * @filp: the file structure
2346  * @buffer: the user buffer
2347  * @lenp: the size of the user buffer
2348  * @ppos: file position
2349  * @ppos: the current position in the file
2350  *
2351  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2352  * values from/to the user buffer, treated as an ASCII string.
2353  * The values read are assumed to be in 1/1000 seconds, and
2354  * are converted into jiffies.
2355  *
2356  * Returns 0 on success.
2357  */
2358 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2359                              void __user *buffer, size_t *lenp, loff_t *ppos)
2360 {
2361         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2362                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2363 }
2364
2365 #ifdef CONFIG_SYSVIPC
2366 static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
2367         void __user *buffer, size_t *lenp, loff_t *ppos)
2368 {
2369         void *which;
2370         which = get_ipc(table, write);
2371         return __do_proc_dointvec(which, table, write, filp, buffer,
2372                         lenp, ppos, NULL, NULL);
2373 }
2374
2375 static int proc_ipc_doulongvec_minmax(ctl_table *table, int write,
2376         struct file *filp, void __user *buffer, size_t *lenp, loff_t *ppos)
2377 {
2378         void *which;
2379         which = get_ipc(table, write);
2380         return __do_proc_doulongvec_minmax(which, table, write, filp, buffer,
2381                         lenp, ppos, 1l, 1l);
2382 }
2383
2384 #endif
2385
2386 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
2387                            void __user *buffer, size_t *lenp, loff_t *ppos)
2388 {
2389         struct pid *new_pid;
2390         pid_t tmp;
2391         int r;
2392
2393         tmp = pid_nr(cad_pid);
2394
2395         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2396                                lenp, ppos, NULL, NULL);
2397         if (r || !write)
2398                 return r;
2399
2400         new_pid = find_get_pid(tmp);
2401         if (!new_pid)
2402                 return -ESRCH;
2403
2404         put_pid(xchg(&cad_pid, new_pid));
2405         return 0;
2406 }
2407
2408 #else /* CONFIG_PROC_FS */
2409
2410 int proc_dostring(ctl_table *table, int write, struct file *filp,
2411                   void __user *buffer, size_t *lenp, loff_t *ppos)
2412 {
2413         return -ENOSYS;
2414 }
2415
2416 static int proc_do_uts_string(ctl_table *table, int write, struct file *filp,
2417                 void __user *buffer, size_t *lenp, loff_t *ppos)
2418 {
2419         return -ENOSYS;
2420 }
2421
2422 #ifdef CONFIG_SYSVIPC
2423 static int proc_do_ipc_string(ctl_table *table, int write, struct file *filp,
2424                 void __user *buffer, size_t *lenp, loff_t *ppos)
2425 {
2426         return -ENOSYS;
2427 }
2428 static int proc_ipc_dointvec(ctl_table *table, int write, struct file *filp,
2429                 void __user *buffer, size_t *lenp, loff_t *ppos)
2430 {
2431         return -ENOSYS;
2432 }
2433 static int proc_ipc_doulongvec_minmax(ctl_table *table, int write,
2434                 struct file *filp, void __user *buffer,
2435                 size_t *lenp, loff_t *ppos)
2436 {
2437         return -ENOSYS;
2438 }
2439 #endif
2440
2441 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2442                   void __user *buffer, size_t *lenp, loff_t *ppos)
2443 {
2444         return -ENOSYS;
2445 }
2446
2447 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2448                         void __user *buffer, size_t *lenp, loff_t *ppos)
2449 {
2450         return -ENOSYS;
2451 }
2452
2453 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2454                     void __user *buffer, size_t *lenp, loff_t *ppos)
2455 {
2456         return -ENOSYS;
2457 }
2458
2459 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2460                     void __user *buffer, size_t *lenp, loff_t *ppos)
2461 {
2462         return -ENOSYS;
2463 }
2464
2465 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2466                     void __user *buffer, size_t *lenp, loff_t *ppos)
2467 {
2468         return -ENOSYS;
2469 }
2470
2471 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2472                              void __user *buffer, size_t *lenp, loff_t *ppos)
2473 {
2474         return -ENOSYS;
2475 }
2476
2477 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2478                     void __user *buffer, size_t *lenp, loff_t *ppos)
2479 {
2480         return -ENOSYS;
2481 }
2482
2483 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2484                                       struct file *filp,
2485                                       void __user *buffer,
2486                                       size_t *lenp, loff_t *ppos)
2487 {
2488     return -ENOSYS;
2489 }
2490
2491
2492 #endif /* CONFIG_PROC_FS */
2493
2494
2495 #ifdef CONFIG_SYSCTL_SYSCALL
2496 /*
2497  * General sysctl support routines
2498  */
2499
2500 /* The generic string strategy routine: */
2501 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2502                   void __user *oldval, size_t __user *oldlenp,
2503                   void __user *newval, size_t newlen)
2504 {
2505         if (!table->data || !table->maxlen)
2506                 return -ENOTDIR;
2507
2508         if (oldval && oldlenp) {
2509                 size_t bufsize;
2510                 if (get_user(bufsize, oldlenp))
2511                         return -EFAULT;
2512                 if (bufsize) {
2513                         size_t len = strlen(table->data), copied;
2514
2515                         /* This shouldn't trigger for a well-formed sysctl */
2516                         if (len > table->maxlen)
2517                                 len = table->maxlen;
2518
2519                         /* Copy up to a max of bufsize-1 bytes of the string */
2520                         copied = (len >= bufsize) ? bufsize - 1 : len;
2521
2522                         if (copy_to_user(oldval, table->data, copied) ||
2523                             put_user(0, (char __user *)(oldval + copied)))
2524                                 return -EFAULT;
2525                         if (put_user(len, oldlenp))
2526                                 return -EFAULT;
2527                 }
2528         }
2529         if (newval && newlen) {
2530                 size_t len = newlen;
2531                 if (len > table->maxlen)
2532                         len = table->maxlen;
2533                 if(copy_from_user(table->data, newval, len))
2534                         return -EFAULT;
2535                 if (len == table->maxlen)
2536                         len--;
2537                 ((char *) table->data)[len] = 0;
2538         }
2539         return 1;
2540 }
2541
2542 /*
2543  * This function makes sure that all of the integers in the vector
2544  * are between the minimum and maximum values given in the arrays
2545  * table->extra1 and table->extra2, respectively.
2546  */
2547 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2548                 void __user *oldval, size_t __user *oldlenp,
2549                 void __user *newval, size_t newlen)
2550 {
2551
2552         if (newval && newlen) {
2553                 int __user *vec = (int __user *) newval;
2554                 int *min = (int *) table->extra1;
2555                 int *max = (int *) table->extra2;
2556                 size_t length;
2557                 int i;
2558
2559                 if (newlen % sizeof(int) != 0)
2560                         return -EINVAL;
2561
2562                 if (!table->extra1 && !table->extra2)
2563                         return 0;
2564
2565                 if (newlen > table->maxlen)
2566                         newlen = table->maxlen;
2567                 length = newlen / sizeof(int);
2568
2569                 for (i = 0; i < length; i++) {
2570                         int value;
2571                         if (get_user(value, vec + i))
2572                                 return -EFAULT;
2573                         if (min && value < min[i])
2574                                 return -EINVAL;
2575                         if (max && value > max[i])
2576                                 return -EINVAL;
2577                 }
2578         }
2579         return 0;
2580 }
2581
2582 /* Strategy function to convert jiffies to seconds */
2583 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2584                 void __user *oldval, size_t __user *oldlenp,
2585                 void __user *newval, size_t newlen)
2586 {
2587         if (oldval && oldlenp) {
2588                 size_t olen;
2589
2590                 if (get_user(olen, oldlenp))
2591                         return -EFAULT;
2592                 if (olen) {
2593                         int val;
2594
2595                         if (olen < sizeof(int))
2596                                 return -EINVAL;
2597
2598                         val = *(int *)(table->data) / HZ;
2599                         if (put_user(val, (int __user *)oldval))
2600                                 return -EFAULT;
2601                         if (put_user(sizeof(int), oldlenp))
2602                                 return -EFAULT;
2603                 }
2604         }
2605         if (newval && newlen) {
2606                 int new;
2607                 if (newlen != sizeof(int))
2608                         return -EINVAL;
2609                 if (get_user(new, (int __user *)newval))
2610                         return -EFAULT;
2611                 *(int *)(table->data) = new*HZ;
2612         }
2613         return 1;
2614 }
2615
2616 /* Strategy function to convert jiffies to seconds */
2617 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2618                 void __user *oldval, size_t __user *oldlenp,
2619                 void __user *newval, size_t newlen)
2620 {
2621         if (oldval && oldlenp) {
2622                 size_t olen;
2623
2624                 if (get_user(olen, oldlenp))
2625                         return -EFAULT;
2626                 if (olen) {
2627                         int val;
2628
2629                         if (olen < sizeof(int))
2630                                 return -EINVAL;
2631
2632                         val = jiffies_to_msecs(*(int *)(table->data));
2633                         if (put_user(val, (int __user *)oldval))
2634                                 return -EFAULT;
2635                         if (put_user(sizeof(int), oldlenp))
2636                                 return -EFAULT;
2637                 }
2638         }
2639         if (newval && newlen) {
2640                 int new;
2641                 if (newlen != sizeof(int))
2642                         return -EINVAL;
2643                 if (get_user(new, (int __user *)newval))
2644                         return -EFAULT;
2645                 *(int *)(table->data) = msecs_to_jiffies(new);
2646         }
2647         return 1;
2648 }
2649
2650
2651 /* The generic string strategy routine: */
2652 static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen,
2653                   void __user *oldval, size_t __user *oldlenp,
2654                   void __user *newval, size_t newlen)
2655 {
2656         struct ctl_table uts_table;
2657         int r, write;
2658         write = newval && newlen;
2659         memcpy(&uts_table, table, sizeof(uts_table));
2660         uts_table.data = get_uts(table, write);
2661         r = sysctl_string(&uts_table, name, nlen,
2662                 oldval, oldlenp, newval, newlen);
2663         put_uts(table, write, uts_table.data);
2664         return r;
2665 }
2666
2667 #ifdef CONFIG_SYSVIPC
2668 /* The generic sysctl ipc data routine. */
2669 static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
2670                 void __user *oldval, size_t __user *oldlenp,
2671                 void __user *newval, size_t newlen)
2672 {
2673         size_t len;
2674         void *data;
2675
2676         /* Get out of I don't have a variable */
2677         if (!table->data || !table->maxlen)
2678                 return -ENOTDIR;
2679
2680         data = get_ipc(table, 1);
2681         if (!data)
2682                 return -ENOTDIR;
2683
2684         if (oldval && oldlenp) {
2685                 if (get_user(len, oldlenp))
2686                         return -EFAULT;
2687                 if (len) {
2688                         if (len > table->maxlen)
2689                                 len = table->maxlen;
2690                         if (copy_to_user(oldval, data, len))
2691                                 return -EFAULT;
2692                         if (put_user(len, oldlenp))
2693                                 return -EFAULT;
2694                 }
2695         }
2696
2697         if (newval && newlen) {
2698                 if (newlen > table->maxlen)
2699                         newlen = table->maxlen;
2700
2701                 if (copy_from_user(data, newval, newlen))
2702                         return -EFAULT;
2703         }
2704         return 1;
2705 }
2706 #endif
2707
2708 #else /* CONFIG_SYSCTL_SYSCALL */
2709
2710
2711 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2712 {
2713         static int msg_count;
2714         struct __sysctl_args tmp;
2715         int name[CTL_MAXNAME];
2716         int i;
2717
2718         /* Read in the sysctl name for better debug message logging */
2719         if (copy_from_user(&tmp, args, sizeof(tmp)))
2720                 return -EFAULT;
2721         if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
2722                 return -ENOTDIR;
2723         for (i = 0; i < tmp.nlen; i++)
2724                 if (get_user(name[i], tmp.name + i))
2725                         return -EFAULT;
2726
2727         /* Ignore accesses to kernel.version */
2728         if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2729                 goto out;
2730
2731         if (msg_count < 5) {
2732                 msg_count++;
2733                 printk(KERN_INFO
2734                         "warning: process `%s' used the removed sysctl "
2735                         "system call with ", current->comm);
2736                 for (i = 0; i < tmp.nlen; i++)
2737                         printk("%d.", name[i]);
2738                 printk("\n");
2739         }
2740 out:
2741         return -ENOSYS;
2742 }
2743
2744 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2745                   void __user *oldval, size_t __user *oldlenp,
2746                   void __user *newval, size_t newlen)
2747 {
2748         return -ENOSYS;
2749 }
2750
2751 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2752                 void __user *oldval, size_t __user *oldlenp,
2753                 void __user *newval, size_t newlen)
2754 {
2755         return -ENOSYS;
2756 }
2757
2758 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2759                 void __user *oldval, size_t __user *oldlenp,
2760                 void __user *newval, size_t newlen)
2761 {
2762         return -ENOSYS;
2763 }
2764
2765 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2766                 void __user *oldval, size_t __user *oldlenp,
2767                 void __user *newval, size_t newlen)
2768 {
2769         return -ENOSYS;
2770 }
2771
2772 static int sysctl_uts_string(ctl_table *table, int __user *name, int nlen,
2773                   void __user *oldval, size_t __user *oldlenp,
2774                   void __user *newval, size_t newlen)
2775 {
2776         return -ENOSYS;
2777 }
2778 #ifdef CONFIG_SYSVIPC
2779 static int sysctl_ipc_data(ctl_table *table, int __user *name, int nlen,
2780                 void __user *oldval, size_t __user *oldlenp,
2781                 void __user *newval, size_t newlen)
2782 {
2783         return -ENOSYS;
2784 }
2785 #endif
2786 #endif /* CONFIG_SYSCTL_SYSCALL */
2787
2788 /*
2789  * No sense putting this after each symbol definition, twice,
2790  * exception granted :-)
2791  */
2792 EXPORT_SYMBOL(proc_dointvec);
2793 EXPORT_SYMBOL(proc_dointvec_jiffies);
2794 EXPORT_SYMBOL(proc_dointvec_minmax);
2795 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2796 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2797 EXPORT_SYMBOL(proc_dostring);
2798 EXPORT_SYMBOL(proc_doulongvec_minmax);
2799 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2800 EXPORT_SYMBOL(register_sysctl_table);
2801 EXPORT_SYMBOL(sysctl_intvec);
2802 EXPORT_SYMBOL(sysctl_jiffies);
2803 EXPORT_SYMBOL(sysctl_ms_jiffies);
2804 EXPORT_SYMBOL(sysctl_string);
2805 EXPORT_SYMBOL(unregister_sysctl_table);