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, ¶m); 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); 2806