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/security.h> 28 #include <linux/ctype.h> 29 #include <linux/utsname.h> 30 #include <linux/smp_lock.h> 31 #include <linux/fs.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 #include <linux/reboot.h> 49 50 #include <asm/uaccess.h> 51 #include <asm/processor.h> 52 53 #ifdef CONFIG_X86 54 #include <asm/nmi.h> 55 #include <asm/stacktrace.h> 56 #endif 57 58 static int deprecated_sysctl_warning(struct __sysctl_args *args); 59 60 #if defined(CONFIG_SYSCTL) 61 62 /* External variables not in a header file. */ 63 extern int C_A_D; 64 extern int print_fatal_signals; 65 extern int sysctl_overcommit_memory; 66 extern int sysctl_overcommit_ratio; 67 extern int sysctl_panic_on_oom; 68 extern int sysctl_oom_kill_allocating_task; 69 extern int max_threads; 70 extern int core_uses_pid; 71 extern int suid_dumpable; 72 extern char core_pattern[]; 73 extern int pid_max; 74 extern int min_free_kbytes; 75 extern int printk_ratelimit_jiffies; 76 extern int printk_ratelimit_burst; 77 extern int pid_max_min, pid_max_max; 78 extern int sysctl_drop_caches; 79 extern int percpu_pagelist_fraction; 80 extern int compat_log; 81 extern int maps_protect; 82 extern int sysctl_stat_interval; 83 extern int audit_argv_kb; 84 extern int latencytop_enabled; 85 86 /* Constants used for minimum and maximum */ 87 #ifdef CONFIG_DETECT_SOFTLOCKUP 88 static int one = 1; 89 static int sixty = 60; 90 #endif 91 92 #ifdef CONFIG_MMU 93 static int two = 2; 94 #endif 95 96 static int zero; 97 static int one_hundred = 100; 98 99 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */ 100 static int maxolduid = 65535; 101 static int minolduid; 102 static int min_percpu_pagelist_fract = 8; 103 104 static int ngroups_max = NGROUPS_MAX; 105 106 #ifdef CONFIG_KMOD 107 extern char modprobe_path[]; 108 #endif 109 #ifdef CONFIG_CHR_DEV_SG 110 extern int sg_big_buff; 111 #endif 112 113 #ifdef __sparc__ 114 extern char reboot_command []; 115 extern int stop_a_enabled; 116 extern int scons_pwroff; 117 #endif 118 119 #ifdef __hppa__ 120 extern int pwrsw_enabled; 121 extern int unaligned_enabled; 122 #endif 123 124 #ifdef CONFIG_S390 125 #ifdef CONFIG_MATHEMU 126 extern int sysctl_ieee_emulation_warnings; 127 #endif 128 extern int sysctl_userprocess_debug; 129 extern int spin_retry; 130 #endif 131 132 extern int sysctl_hz_timer; 133 134 #ifdef CONFIG_BSD_PROCESS_ACCT 135 extern int acct_parm[]; 136 #endif 137 138 #ifdef CONFIG_IA64 139 extern int no_unaligned_warning; 140 #endif 141 142 #ifdef CONFIG_RT_MUTEXES 143 extern int max_lock_depth; 144 #endif 145 146 #ifdef CONFIG_SYSCTL_SYSCALL 147 static int parse_table(int __user *, int, void __user *, size_t __user *, 148 void __user *, size_t, struct ctl_table *); 149 #endif 150 151 152 #ifdef CONFIG_PROC_SYSCTL 153 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp, 154 void __user *buffer, size_t *lenp, loff_t *ppos); 155 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp, 156 void __user *buffer, size_t *lenp, loff_t *ppos); 157 #endif 158 159 static struct ctl_table root_table[]; 160 static struct ctl_table_header root_table_header = 161 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) }; 162 163 static struct ctl_table kern_table[]; 164 static struct ctl_table vm_table[]; 165 static struct ctl_table fs_table[]; 166 static struct ctl_table debug_table[]; 167 static struct ctl_table dev_table[]; 168 extern struct ctl_table random_table[]; 169 #ifdef CONFIG_INOTIFY_USER 170 extern struct ctl_table inotify_table[]; 171 #endif 172 173 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 174 int sysctl_legacy_va_layout; 175 #endif 176 177 extern int prove_locking; 178 extern int lock_stat; 179 180 /* The default sysctl tables: */ 181 182 static struct ctl_table root_table[] = { 183 { 184 .ctl_name = CTL_KERN, 185 .procname = "kernel", 186 .mode = 0555, 187 .child = kern_table, 188 }, 189 { 190 .ctl_name = CTL_VM, 191 .procname = "vm", 192 .mode = 0555, 193 .child = vm_table, 194 }, 195 #ifdef CONFIG_NET 196 { 197 .ctl_name = CTL_NET, 198 .procname = "net", 199 .mode = 0555, 200 .child = net_table, 201 }, 202 #endif 203 { 204 .ctl_name = CTL_FS, 205 .procname = "fs", 206 .mode = 0555, 207 .child = fs_table, 208 }, 209 { 210 .ctl_name = CTL_DEBUG, 211 .procname = "debug", 212 .mode = 0555, 213 .child = debug_table, 214 }, 215 { 216 .ctl_name = CTL_DEV, 217 .procname = "dev", 218 .mode = 0555, 219 .child = dev_table, 220 }, 221 /* 222 * NOTE: do not add new entries to this table unless you have read 223 * Documentation/sysctl/ctl_unnumbered.txt 224 */ 225 { .ctl_name = 0 } 226 }; 227 228 #ifdef CONFIG_SCHED_DEBUG 229 static int min_sched_granularity_ns = 100000; /* 100 usecs */ 230 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */ 231 static int min_wakeup_granularity_ns; /* 0 usecs */ 232 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */ 233 #endif 234 235 static struct ctl_table kern_table[] = { 236 #ifdef CONFIG_SCHED_DEBUG 237 { 238 .ctl_name = CTL_UNNUMBERED, 239 .procname = "sched_min_granularity_ns", 240 .data = &sysctl_sched_min_granularity, 241 .maxlen = sizeof(unsigned int), 242 .mode = 0644, 243 .proc_handler = &sched_nr_latency_handler, 244 .strategy = &sysctl_intvec, 245 .extra1 = &min_sched_granularity_ns, 246 .extra2 = &max_sched_granularity_ns, 247 }, 248 { 249 .ctl_name = CTL_UNNUMBERED, 250 .procname = "sched_latency_ns", 251 .data = &sysctl_sched_latency, 252 .maxlen = sizeof(unsigned int), 253 .mode = 0644, 254 .proc_handler = &sched_nr_latency_handler, 255 .strategy = &sysctl_intvec, 256 .extra1 = &min_sched_granularity_ns, 257 .extra2 = &max_sched_granularity_ns, 258 }, 259 { 260 .ctl_name = CTL_UNNUMBERED, 261 .procname = "sched_wakeup_granularity_ns", 262 .data = &sysctl_sched_wakeup_granularity, 263 .maxlen = sizeof(unsigned int), 264 .mode = 0644, 265 .proc_handler = &proc_dointvec_minmax, 266 .strategy = &sysctl_intvec, 267 .extra1 = &min_wakeup_granularity_ns, 268 .extra2 = &max_wakeup_granularity_ns, 269 }, 270 { 271 .ctl_name = CTL_UNNUMBERED, 272 .procname = "sched_batch_wakeup_granularity_ns", 273 .data = &sysctl_sched_batch_wakeup_granularity, 274 .maxlen = sizeof(unsigned int), 275 .mode = 0644, 276 .proc_handler = &proc_dointvec_minmax, 277 .strategy = &sysctl_intvec, 278 .extra1 = &min_wakeup_granularity_ns, 279 .extra2 = &max_wakeup_granularity_ns, 280 }, 281 { 282 .ctl_name = CTL_UNNUMBERED, 283 .procname = "sched_child_runs_first", 284 .data = &sysctl_sched_child_runs_first, 285 .maxlen = sizeof(unsigned int), 286 .mode = 0644, 287 .proc_handler = &proc_dointvec, 288 }, 289 { 290 .ctl_name = CTL_UNNUMBERED, 291 .procname = "sched_features", 292 .data = &sysctl_sched_features, 293 .maxlen = sizeof(unsigned int), 294 .mode = 0644, 295 .proc_handler = &proc_dointvec, 296 }, 297 { 298 .ctl_name = CTL_UNNUMBERED, 299 .procname = "sched_migration_cost", 300 .data = &sysctl_sched_migration_cost, 301 .maxlen = sizeof(unsigned int), 302 .mode = 0644, 303 .proc_handler = &proc_dointvec, 304 }, 305 { 306 .ctl_name = CTL_UNNUMBERED, 307 .procname = "sched_nr_migrate", 308 .data = &sysctl_sched_nr_migrate, 309 .maxlen = sizeof(unsigned int), 310 .mode = 0644, 311 .proc_handler = &proc_dointvec, 312 }, 313 { 314 .ctl_name = CTL_UNNUMBERED, 315 .procname = "sched_rt_period_ms", 316 .data = &sysctl_sched_rt_period, 317 .maxlen = sizeof(unsigned int), 318 .mode = 0644, 319 .proc_handler = &proc_dointvec, 320 }, 321 { 322 .ctl_name = CTL_UNNUMBERED, 323 .procname = "sched_rt_ratio", 324 .data = &sysctl_sched_rt_ratio, 325 .maxlen = sizeof(unsigned int), 326 .mode = 0644, 327 .proc_handler = &proc_dointvec, 328 }, 329 #if defined(CONFIG_FAIR_GROUP_SCHED) && defined(CONFIG_SMP) 330 { 331 .ctl_name = CTL_UNNUMBERED, 332 .procname = "sched_min_bal_int_shares", 333 .data = &sysctl_sched_min_bal_int_shares, 334 .maxlen = sizeof(unsigned int), 335 .mode = 0644, 336 .proc_handler = &proc_dointvec, 337 }, 338 { 339 .ctl_name = CTL_UNNUMBERED, 340 .procname = "sched_max_bal_int_shares", 341 .data = &sysctl_sched_max_bal_int_shares, 342 .maxlen = sizeof(unsigned int), 343 .mode = 0644, 344 .proc_handler = &proc_dointvec, 345 }, 346 #endif 347 #endif 348 { 349 .ctl_name = CTL_UNNUMBERED, 350 .procname = "sched_compat_yield", 351 .data = &sysctl_sched_compat_yield, 352 .maxlen = sizeof(unsigned int), 353 .mode = 0644, 354 .proc_handler = &proc_dointvec, 355 }, 356 #ifdef CONFIG_PROVE_LOCKING 357 { 358 .ctl_name = CTL_UNNUMBERED, 359 .procname = "prove_locking", 360 .data = &prove_locking, 361 .maxlen = sizeof(int), 362 .mode = 0644, 363 .proc_handler = &proc_dointvec, 364 }, 365 #endif 366 #ifdef CONFIG_LOCK_STAT 367 { 368 .ctl_name = CTL_UNNUMBERED, 369 .procname = "lock_stat", 370 .data = &lock_stat, 371 .maxlen = sizeof(int), 372 .mode = 0644, 373 .proc_handler = &proc_dointvec, 374 }, 375 #endif 376 { 377 .ctl_name = KERN_PANIC, 378 .procname = "panic", 379 .data = &panic_timeout, 380 .maxlen = sizeof(int), 381 .mode = 0644, 382 .proc_handler = &proc_dointvec, 383 }, 384 { 385 .ctl_name = KERN_CORE_USES_PID, 386 .procname = "core_uses_pid", 387 .data = &core_uses_pid, 388 .maxlen = sizeof(int), 389 .mode = 0644, 390 .proc_handler = &proc_dointvec, 391 }, 392 #ifdef CONFIG_AUDITSYSCALL 393 { 394 .ctl_name = CTL_UNNUMBERED, 395 .procname = "audit_argv_kb", 396 .data = &audit_argv_kb, 397 .maxlen = sizeof(int), 398 .mode = 0644, 399 .proc_handler = &proc_dointvec, 400 }, 401 #endif 402 { 403 .ctl_name = KERN_CORE_PATTERN, 404 .procname = "core_pattern", 405 .data = core_pattern, 406 .maxlen = CORENAME_MAX_SIZE, 407 .mode = 0644, 408 .proc_handler = &proc_dostring, 409 .strategy = &sysctl_string, 410 }, 411 #ifdef CONFIG_PROC_SYSCTL 412 { 413 .procname = "tainted", 414 .data = &tainted, 415 .maxlen = sizeof(int), 416 .mode = 0644, 417 .proc_handler = &proc_dointvec_taint, 418 }, 419 #endif 420 #ifdef CONFIG_LATENCYTOP 421 { 422 .procname = "latencytop", 423 .data = &latencytop_enabled, 424 .maxlen = sizeof(int), 425 .mode = 0644, 426 .proc_handler = &proc_dointvec, 427 }, 428 #endif 429 #ifdef CONFIG_SECURITY_CAPABILITIES 430 { 431 .procname = "cap-bound", 432 .data = &cap_bset, 433 .maxlen = sizeof(kernel_cap_t), 434 .mode = 0600, 435 .proc_handler = &proc_dointvec_bset, 436 }, 437 #endif /* def CONFIG_SECURITY_CAPABILITIES */ 438 #ifdef CONFIG_BLK_DEV_INITRD 439 { 440 .ctl_name = KERN_REALROOTDEV, 441 .procname = "real-root-dev", 442 .data = &real_root_dev, 443 .maxlen = sizeof(int), 444 .mode = 0644, 445 .proc_handler = &proc_dointvec, 446 }, 447 #endif 448 { 449 .ctl_name = CTL_UNNUMBERED, 450 .procname = "print-fatal-signals", 451 .data = &print_fatal_signals, 452 .maxlen = sizeof(int), 453 .mode = 0644, 454 .proc_handler = &proc_dointvec, 455 }, 456 #ifdef __sparc__ 457 { 458 .ctl_name = KERN_SPARC_REBOOT, 459 .procname = "reboot-cmd", 460 .data = reboot_command, 461 .maxlen = 256, 462 .mode = 0644, 463 .proc_handler = &proc_dostring, 464 .strategy = &sysctl_string, 465 }, 466 { 467 .ctl_name = KERN_SPARC_STOP_A, 468 .procname = "stop-a", 469 .data = &stop_a_enabled, 470 .maxlen = sizeof (int), 471 .mode = 0644, 472 .proc_handler = &proc_dointvec, 473 }, 474 { 475 .ctl_name = KERN_SPARC_SCONS_PWROFF, 476 .procname = "scons-poweroff", 477 .data = &scons_pwroff, 478 .maxlen = sizeof (int), 479 .mode = 0644, 480 .proc_handler = &proc_dointvec, 481 }, 482 #endif 483 #ifdef __hppa__ 484 { 485 .ctl_name = KERN_HPPA_PWRSW, 486 .procname = "soft-power", 487 .data = &pwrsw_enabled, 488 .maxlen = sizeof (int), 489 .mode = 0644, 490 .proc_handler = &proc_dointvec, 491 }, 492 { 493 .ctl_name = KERN_HPPA_UNALIGNED, 494 .procname = "unaligned-trap", 495 .data = &unaligned_enabled, 496 .maxlen = sizeof (int), 497 .mode = 0644, 498 .proc_handler = &proc_dointvec, 499 }, 500 #endif 501 { 502 .ctl_name = KERN_CTLALTDEL, 503 .procname = "ctrl-alt-del", 504 .data = &C_A_D, 505 .maxlen = sizeof(int), 506 .mode = 0644, 507 .proc_handler = &proc_dointvec, 508 }, 509 { 510 .ctl_name = KERN_PRINTK, 511 .procname = "printk", 512 .data = &console_loglevel, 513 .maxlen = 4*sizeof(int), 514 .mode = 0644, 515 .proc_handler = &proc_dointvec, 516 }, 517 #ifdef CONFIG_KMOD 518 { 519 .ctl_name = KERN_MODPROBE, 520 .procname = "modprobe", 521 .data = &modprobe_path, 522 .maxlen = KMOD_PATH_LEN, 523 .mode = 0644, 524 .proc_handler = &proc_dostring, 525 .strategy = &sysctl_string, 526 }, 527 #endif 528 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET) 529 { 530 .ctl_name = KERN_HOTPLUG, 531 .procname = "hotplug", 532 .data = &uevent_helper, 533 .maxlen = UEVENT_HELPER_PATH_LEN, 534 .mode = 0644, 535 .proc_handler = &proc_dostring, 536 .strategy = &sysctl_string, 537 }, 538 #endif 539 #ifdef CONFIG_CHR_DEV_SG 540 { 541 .ctl_name = KERN_SG_BIG_BUFF, 542 .procname = "sg-big-buff", 543 .data = &sg_big_buff, 544 .maxlen = sizeof (int), 545 .mode = 0444, 546 .proc_handler = &proc_dointvec, 547 }, 548 #endif 549 #ifdef CONFIG_BSD_PROCESS_ACCT 550 { 551 .ctl_name = KERN_ACCT, 552 .procname = "acct", 553 .data = &acct_parm, 554 .maxlen = 3*sizeof(int), 555 .mode = 0644, 556 .proc_handler = &proc_dointvec, 557 }, 558 #endif 559 #ifdef CONFIG_MAGIC_SYSRQ 560 { 561 .ctl_name = KERN_SYSRQ, 562 .procname = "sysrq", 563 .data = &__sysrq_enabled, 564 .maxlen = sizeof (int), 565 .mode = 0644, 566 .proc_handler = &proc_dointvec, 567 }, 568 #endif 569 #ifdef CONFIG_PROC_SYSCTL 570 { 571 .procname = "cad_pid", 572 .data = NULL, 573 .maxlen = sizeof (int), 574 .mode = 0600, 575 .proc_handler = &proc_do_cad_pid, 576 }, 577 #endif 578 { 579 .ctl_name = KERN_MAX_THREADS, 580 .procname = "threads-max", 581 .data = &max_threads, 582 .maxlen = sizeof(int), 583 .mode = 0644, 584 .proc_handler = &proc_dointvec, 585 }, 586 { 587 .ctl_name = KERN_RANDOM, 588 .procname = "random", 589 .mode = 0555, 590 .child = random_table, 591 }, 592 { 593 .ctl_name = KERN_OVERFLOWUID, 594 .procname = "overflowuid", 595 .data = &overflowuid, 596 .maxlen = sizeof(int), 597 .mode = 0644, 598 .proc_handler = &proc_dointvec_minmax, 599 .strategy = &sysctl_intvec, 600 .extra1 = &minolduid, 601 .extra2 = &maxolduid, 602 }, 603 { 604 .ctl_name = KERN_OVERFLOWGID, 605 .procname = "overflowgid", 606 .data = &overflowgid, 607 .maxlen = sizeof(int), 608 .mode = 0644, 609 .proc_handler = &proc_dointvec_minmax, 610 .strategy = &sysctl_intvec, 611 .extra1 = &minolduid, 612 .extra2 = &maxolduid, 613 }, 614 #ifdef CONFIG_S390 615 #ifdef CONFIG_MATHEMU 616 { 617 .ctl_name = KERN_IEEE_EMULATION_WARNINGS, 618 .procname = "ieee_emulation_warnings", 619 .data = &sysctl_ieee_emulation_warnings, 620 .maxlen = sizeof(int), 621 .mode = 0644, 622 .proc_handler = &proc_dointvec, 623 }, 624 #endif 625 #ifdef CONFIG_NO_IDLE_HZ 626 { 627 .ctl_name = KERN_HZ_TIMER, 628 .procname = "hz_timer", 629 .data = &sysctl_hz_timer, 630 .maxlen = sizeof(int), 631 .mode = 0644, 632 .proc_handler = &proc_dointvec, 633 }, 634 #endif 635 { 636 .ctl_name = KERN_S390_USER_DEBUG_LOGGING, 637 .procname = "userprocess_debug", 638 .data = &sysctl_userprocess_debug, 639 .maxlen = sizeof(int), 640 .mode = 0644, 641 .proc_handler = &proc_dointvec, 642 }, 643 #endif 644 { 645 .ctl_name = KERN_PIDMAX, 646 .procname = "pid_max", 647 .data = &pid_max, 648 .maxlen = sizeof (int), 649 .mode = 0644, 650 .proc_handler = &proc_dointvec_minmax, 651 .strategy = sysctl_intvec, 652 .extra1 = &pid_max_min, 653 .extra2 = &pid_max_max, 654 }, 655 { 656 .ctl_name = KERN_PANIC_ON_OOPS, 657 .procname = "panic_on_oops", 658 .data = &panic_on_oops, 659 .maxlen = sizeof(int), 660 .mode = 0644, 661 .proc_handler = &proc_dointvec, 662 }, 663 { 664 .ctl_name = KERN_PRINTK_RATELIMIT, 665 .procname = "printk_ratelimit", 666 .data = &printk_ratelimit_jiffies, 667 .maxlen = sizeof(int), 668 .mode = 0644, 669 .proc_handler = &proc_dointvec_jiffies, 670 .strategy = &sysctl_jiffies, 671 }, 672 { 673 .ctl_name = KERN_PRINTK_RATELIMIT_BURST, 674 .procname = "printk_ratelimit_burst", 675 .data = &printk_ratelimit_burst, 676 .maxlen = sizeof(int), 677 .mode = 0644, 678 .proc_handler = &proc_dointvec, 679 }, 680 { 681 .ctl_name = KERN_NGROUPS_MAX, 682 .procname = "ngroups_max", 683 .data = &ngroups_max, 684 .maxlen = sizeof (int), 685 .mode = 0444, 686 .proc_handler = &proc_dointvec, 687 }, 688 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) 689 { 690 .ctl_name = KERN_UNKNOWN_NMI_PANIC, 691 .procname = "unknown_nmi_panic", 692 .data = &unknown_nmi_panic, 693 .maxlen = sizeof (int), 694 .mode = 0644, 695 .proc_handler = &proc_dointvec, 696 }, 697 { 698 .procname = "nmi_watchdog", 699 .data = &nmi_watchdog_enabled, 700 .maxlen = sizeof (int), 701 .mode = 0644, 702 .proc_handler = &proc_nmi_enabled, 703 }, 704 #endif 705 #if defined(CONFIG_X86) 706 { 707 .ctl_name = KERN_PANIC_ON_NMI, 708 .procname = "panic_on_unrecovered_nmi", 709 .data = &panic_on_unrecovered_nmi, 710 .maxlen = sizeof(int), 711 .mode = 0644, 712 .proc_handler = &proc_dointvec, 713 }, 714 { 715 .ctl_name = KERN_BOOTLOADER_TYPE, 716 .procname = "bootloader_type", 717 .data = &bootloader_type, 718 .maxlen = sizeof (int), 719 .mode = 0444, 720 .proc_handler = &proc_dointvec, 721 }, 722 { 723 .ctl_name = CTL_UNNUMBERED, 724 .procname = "kstack_depth_to_print", 725 .data = &kstack_depth_to_print, 726 .maxlen = sizeof(int), 727 .mode = 0644, 728 .proc_handler = &proc_dointvec, 729 }, 730 #endif 731 #if defined(CONFIG_MMU) 732 { 733 .ctl_name = KERN_RANDOMIZE, 734 .procname = "randomize_va_space", 735 .data = &randomize_va_space, 736 .maxlen = sizeof(int), 737 .mode = 0644, 738 .proc_handler = &proc_dointvec, 739 }, 740 #endif 741 #if defined(CONFIG_S390) && defined(CONFIG_SMP) 742 { 743 .ctl_name = KERN_SPIN_RETRY, 744 .procname = "spin_retry", 745 .data = &spin_retry, 746 .maxlen = sizeof (int), 747 .mode = 0644, 748 .proc_handler = &proc_dointvec, 749 }, 750 #endif 751 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86) 752 { 753 .procname = "acpi_video_flags", 754 .data = &acpi_realmode_flags, 755 .maxlen = sizeof (unsigned long), 756 .mode = 0644, 757 .proc_handler = &proc_doulongvec_minmax, 758 }, 759 #endif 760 #ifdef CONFIG_IA64 761 { 762 .ctl_name = KERN_IA64_UNALIGNED, 763 .procname = "ignore-unaligned-usertrap", 764 .data = &no_unaligned_warning, 765 .maxlen = sizeof (int), 766 .mode = 0644, 767 .proc_handler = &proc_dointvec, 768 }, 769 #endif 770 #ifdef CONFIG_DETECT_SOFTLOCKUP 771 { 772 .ctl_name = CTL_UNNUMBERED, 773 .procname = "softlockup_thresh", 774 .data = &softlockup_thresh, 775 .maxlen = sizeof(unsigned long), 776 .mode = 0644, 777 .proc_handler = &proc_doulongvec_minmax, 778 .strategy = &sysctl_intvec, 779 .extra1 = &one, 780 .extra2 = &sixty, 781 }, 782 { 783 .ctl_name = CTL_UNNUMBERED, 784 .procname = "hung_task_check_count", 785 .data = &sysctl_hung_task_check_count, 786 .maxlen = sizeof(unsigned long), 787 .mode = 0644, 788 .proc_handler = &proc_doulongvec_minmax, 789 .strategy = &sysctl_intvec, 790 }, 791 { 792 .ctl_name = CTL_UNNUMBERED, 793 .procname = "hung_task_timeout_secs", 794 .data = &sysctl_hung_task_timeout_secs, 795 .maxlen = sizeof(unsigned long), 796 .mode = 0644, 797 .proc_handler = &proc_doulongvec_minmax, 798 .strategy = &sysctl_intvec, 799 }, 800 { 801 .ctl_name = CTL_UNNUMBERED, 802 .procname = "hung_task_warnings", 803 .data = &sysctl_hung_task_warnings, 804 .maxlen = sizeof(unsigned long), 805 .mode = 0644, 806 .proc_handler = &proc_doulongvec_minmax, 807 .strategy = &sysctl_intvec, 808 }, 809 #endif 810 #ifdef CONFIG_COMPAT 811 { 812 .ctl_name = KERN_COMPAT_LOG, 813 .procname = "compat-log", 814 .data = &compat_log, 815 .maxlen = sizeof (int), 816 .mode = 0644, 817 .proc_handler = &proc_dointvec, 818 }, 819 #endif 820 #ifdef CONFIG_RT_MUTEXES 821 { 822 .ctl_name = KERN_MAX_LOCK_DEPTH, 823 .procname = "max_lock_depth", 824 .data = &max_lock_depth, 825 .maxlen = sizeof(int), 826 .mode = 0644, 827 .proc_handler = &proc_dointvec, 828 }, 829 #endif 830 #ifdef CONFIG_PROC_FS 831 { 832 .ctl_name = CTL_UNNUMBERED, 833 .procname = "maps_protect", 834 .data = &maps_protect, 835 .maxlen = sizeof(int), 836 .mode = 0644, 837 .proc_handler = &proc_dointvec, 838 }, 839 #endif 840 { 841 .ctl_name = CTL_UNNUMBERED, 842 .procname = "poweroff_cmd", 843 .data = &poweroff_cmd, 844 .maxlen = POWEROFF_CMD_PATH_LEN, 845 .mode = 0644, 846 .proc_handler = &proc_dostring, 847 .strategy = &sysctl_string, 848 }, 849 /* 850 * NOTE: do not add new entries to this table unless you have read 851 * Documentation/sysctl/ctl_unnumbered.txt 852 */ 853 { .ctl_name = 0 } 854 }; 855 856 static struct ctl_table vm_table[] = { 857 { 858 .ctl_name = VM_OVERCOMMIT_MEMORY, 859 .procname = "overcommit_memory", 860 .data = &sysctl_overcommit_memory, 861 .maxlen = sizeof(sysctl_overcommit_memory), 862 .mode = 0644, 863 .proc_handler = &proc_dointvec, 864 }, 865 { 866 .ctl_name = VM_PANIC_ON_OOM, 867 .procname = "panic_on_oom", 868 .data = &sysctl_panic_on_oom, 869 .maxlen = sizeof(sysctl_panic_on_oom), 870 .mode = 0644, 871 .proc_handler = &proc_dointvec, 872 }, 873 { 874 .ctl_name = CTL_UNNUMBERED, 875 .procname = "oom_kill_allocating_task", 876 .data = &sysctl_oom_kill_allocating_task, 877 .maxlen = sizeof(sysctl_oom_kill_allocating_task), 878 .mode = 0644, 879 .proc_handler = &proc_dointvec, 880 }, 881 { 882 .ctl_name = VM_OVERCOMMIT_RATIO, 883 .procname = "overcommit_ratio", 884 .data = &sysctl_overcommit_ratio, 885 .maxlen = sizeof(sysctl_overcommit_ratio), 886 .mode = 0644, 887 .proc_handler = &proc_dointvec, 888 }, 889 { 890 .ctl_name = VM_PAGE_CLUSTER, 891 .procname = "page-cluster", 892 .data = &page_cluster, 893 .maxlen = sizeof(int), 894 .mode = 0644, 895 .proc_handler = &proc_dointvec, 896 }, 897 { 898 .ctl_name = VM_DIRTY_BACKGROUND, 899 .procname = "dirty_background_ratio", 900 .data = &dirty_background_ratio, 901 .maxlen = sizeof(dirty_background_ratio), 902 .mode = 0644, 903 .proc_handler = &proc_dointvec_minmax, 904 .strategy = &sysctl_intvec, 905 .extra1 = &zero, 906 .extra2 = &one_hundred, 907 }, 908 { 909 .ctl_name = VM_DIRTY_RATIO, 910 .procname = "dirty_ratio", 911 .data = &vm_dirty_ratio, 912 .maxlen = sizeof(vm_dirty_ratio), 913 .mode = 0644, 914 .proc_handler = &dirty_ratio_handler, 915 .strategy = &sysctl_intvec, 916 .extra1 = &zero, 917 .extra2 = &one_hundred, 918 }, 919 { 920 .procname = "dirty_writeback_centisecs", 921 .data = &dirty_writeback_interval, 922 .maxlen = sizeof(dirty_writeback_interval), 923 .mode = 0644, 924 .proc_handler = &dirty_writeback_centisecs_handler, 925 }, 926 { 927 .procname = "dirty_expire_centisecs", 928 .data = &dirty_expire_interval, 929 .maxlen = sizeof(dirty_expire_interval), 930 .mode = 0644, 931 .proc_handler = &proc_dointvec_userhz_jiffies, 932 }, 933 { 934 .ctl_name = VM_NR_PDFLUSH_THREADS, 935 .procname = "nr_pdflush_threads", 936 .data = &nr_pdflush_threads, 937 .maxlen = sizeof nr_pdflush_threads, 938 .mode = 0444 /* read-only*/, 939 .proc_handler = &proc_dointvec, 940 }, 941 { 942 .ctl_name = VM_SWAPPINESS, 943 .procname = "swappiness", 944 .data = &vm_swappiness, 945 .maxlen = sizeof(vm_swappiness), 946 .mode = 0644, 947 .proc_handler = &proc_dointvec_minmax, 948 .strategy = &sysctl_intvec, 949 .extra1 = &zero, 950 .extra2 = &one_hundred, 951 }, 952 #ifdef CONFIG_HUGETLB_PAGE 953 { 954 .procname = "nr_hugepages", 955 .data = &max_huge_pages, 956 .maxlen = sizeof(unsigned long), 957 .mode = 0644, 958 .proc_handler = &hugetlb_sysctl_handler, 959 .extra1 = (void *)&hugetlb_zero, 960 .extra2 = (void *)&hugetlb_infinity, 961 }, 962 { 963 .ctl_name = VM_HUGETLB_GROUP, 964 .procname = "hugetlb_shm_group", 965 .data = &sysctl_hugetlb_shm_group, 966 .maxlen = sizeof(gid_t), 967 .mode = 0644, 968 .proc_handler = &proc_dointvec, 969 }, 970 { 971 .ctl_name = CTL_UNNUMBERED, 972 .procname = "hugepages_treat_as_movable", 973 .data = &hugepages_treat_as_movable, 974 .maxlen = sizeof(int), 975 .mode = 0644, 976 .proc_handler = &hugetlb_treat_movable_handler, 977 }, 978 { 979 .ctl_name = CTL_UNNUMBERED, 980 .procname = "nr_overcommit_hugepages", 981 .data = &nr_overcommit_huge_pages, 982 .maxlen = sizeof(nr_overcommit_huge_pages), 983 .mode = 0644, 984 .proc_handler = &proc_doulongvec_minmax, 985 }, 986 #endif 987 { 988 .ctl_name = VM_LOWMEM_RESERVE_RATIO, 989 .procname = "lowmem_reserve_ratio", 990 .data = &sysctl_lowmem_reserve_ratio, 991 .maxlen = sizeof(sysctl_lowmem_reserve_ratio), 992 .mode = 0644, 993 .proc_handler = &lowmem_reserve_ratio_sysctl_handler, 994 .strategy = &sysctl_intvec, 995 }, 996 { 997 .ctl_name = VM_DROP_PAGECACHE, 998 .procname = "drop_caches", 999 .data = &sysctl_drop_caches, 1000 .maxlen = sizeof(int), 1001 .mode = 0644, 1002 .proc_handler = drop_caches_sysctl_handler, 1003 .strategy = &sysctl_intvec, 1004 }, 1005 { 1006 .ctl_name = VM_MIN_FREE_KBYTES, 1007 .procname = "min_free_kbytes", 1008 .data = &min_free_kbytes, 1009 .maxlen = sizeof(min_free_kbytes), 1010 .mode = 0644, 1011 .proc_handler = &min_free_kbytes_sysctl_handler, 1012 .strategy = &sysctl_intvec, 1013 .extra1 = &zero, 1014 }, 1015 { 1016 .ctl_name = VM_PERCPU_PAGELIST_FRACTION, 1017 .procname = "percpu_pagelist_fraction", 1018 .data = &percpu_pagelist_fraction, 1019 .maxlen = sizeof(percpu_pagelist_fraction), 1020 .mode = 0644, 1021 .proc_handler = &percpu_pagelist_fraction_sysctl_handler, 1022 .strategy = &sysctl_intvec, 1023 .extra1 = &min_percpu_pagelist_fract, 1024 }, 1025 #ifdef CONFIG_MMU 1026 { 1027 .ctl_name = VM_MAX_MAP_COUNT, 1028 .procname = "max_map_count", 1029 .data = &sysctl_max_map_count, 1030 .maxlen = sizeof(sysctl_max_map_count), 1031 .mode = 0644, 1032 .proc_handler = &proc_dointvec 1033 }, 1034 #endif 1035 { 1036 .ctl_name = VM_LAPTOP_MODE, 1037 .procname = "laptop_mode", 1038 .data = &laptop_mode, 1039 .maxlen = sizeof(laptop_mode), 1040 .mode = 0644, 1041 .proc_handler = &proc_dointvec_jiffies, 1042 .strategy = &sysctl_jiffies, 1043 }, 1044 { 1045 .ctl_name = VM_BLOCK_DUMP, 1046 .procname = "block_dump", 1047 .data = &block_dump, 1048 .maxlen = sizeof(block_dump), 1049 .mode = 0644, 1050 .proc_handler = &proc_dointvec, 1051 .strategy = &sysctl_intvec, 1052 .extra1 = &zero, 1053 }, 1054 { 1055 .ctl_name = VM_VFS_CACHE_PRESSURE, 1056 .procname = "vfs_cache_pressure", 1057 .data = &sysctl_vfs_cache_pressure, 1058 .maxlen = sizeof(sysctl_vfs_cache_pressure), 1059 .mode = 0644, 1060 .proc_handler = &proc_dointvec, 1061 .strategy = &sysctl_intvec, 1062 .extra1 = &zero, 1063 }, 1064 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 1065 { 1066 .ctl_name = VM_LEGACY_VA_LAYOUT, 1067 .procname = "legacy_va_layout", 1068 .data = &sysctl_legacy_va_layout, 1069 .maxlen = sizeof(sysctl_legacy_va_layout), 1070 .mode = 0644, 1071 .proc_handler = &proc_dointvec, 1072 .strategy = &sysctl_intvec, 1073 .extra1 = &zero, 1074 }, 1075 #endif 1076 #ifdef CONFIG_NUMA 1077 { 1078 .ctl_name = VM_ZONE_RECLAIM_MODE, 1079 .procname = "zone_reclaim_mode", 1080 .data = &zone_reclaim_mode, 1081 .maxlen = sizeof(zone_reclaim_mode), 1082 .mode = 0644, 1083 .proc_handler = &proc_dointvec, 1084 .strategy = &sysctl_intvec, 1085 .extra1 = &zero, 1086 }, 1087 { 1088 .ctl_name = VM_MIN_UNMAPPED, 1089 .procname = "min_unmapped_ratio", 1090 .data = &sysctl_min_unmapped_ratio, 1091 .maxlen = sizeof(sysctl_min_unmapped_ratio), 1092 .mode = 0644, 1093 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler, 1094 .strategy = &sysctl_intvec, 1095 .extra1 = &zero, 1096 .extra2 = &one_hundred, 1097 }, 1098 { 1099 .ctl_name = VM_MIN_SLAB, 1100 .procname = "min_slab_ratio", 1101 .data = &sysctl_min_slab_ratio, 1102 .maxlen = sizeof(sysctl_min_slab_ratio), 1103 .mode = 0644, 1104 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler, 1105 .strategy = &sysctl_intvec, 1106 .extra1 = &zero, 1107 .extra2 = &one_hundred, 1108 }, 1109 #endif 1110 #ifdef CONFIG_SMP 1111 { 1112 .ctl_name = CTL_UNNUMBERED, 1113 .procname = "stat_interval", 1114 .data = &sysctl_stat_interval, 1115 .maxlen = sizeof(sysctl_stat_interval), 1116 .mode = 0644, 1117 .proc_handler = &proc_dointvec_jiffies, 1118 .strategy = &sysctl_jiffies, 1119 }, 1120 #endif 1121 #ifdef CONFIG_SECURITY 1122 { 1123 .ctl_name = CTL_UNNUMBERED, 1124 .procname = "mmap_min_addr", 1125 .data = &mmap_min_addr, 1126 .maxlen = sizeof(unsigned long), 1127 .mode = 0644, 1128 .proc_handler = &proc_doulongvec_minmax, 1129 }, 1130 #endif 1131 #ifdef CONFIG_NUMA 1132 { 1133 .ctl_name = CTL_UNNUMBERED, 1134 .procname = "numa_zonelist_order", 1135 .data = &numa_zonelist_order, 1136 .maxlen = NUMA_ZONELIST_ORDER_LEN, 1137 .mode = 0644, 1138 .proc_handler = &numa_zonelist_order_handler, 1139 .strategy = &sysctl_string, 1140 }, 1141 #endif 1142 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \ 1143 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL)) 1144 { 1145 .ctl_name = VM_VDSO_ENABLED, 1146 .procname = "vdso_enabled", 1147 .data = &vdso_enabled, 1148 .maxlen = sizeof(vdso_enabled), 1149 .mode = 0644, 1150 .proc_handler = &proc_dointvec, 1151 .strategy = &sysctl_intvec, 1152 .extra1 = &zero, 1153 }, 1154 #endif 1155 /* 1156 * NOTE: do not add new entries to this table unless you have read 1157 * Documentation/sysctl/ctl_unnumbered.txt 1158 */ 1159 { .ctl_name = 0 } 1160 }; 1161 1162 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) 1163 static struct ctl_table binfmt_misc_table[] = { 1164 { .ctl_name = 0 } 1165 }; 1166 #endif 1167 1168 static struct ctl_table fs_table[] = { 1169 { 1170 .ctl_name = FS_NRINODE, 1171 .procname = "inode-nr", 1172 .data = &inodes_stat, 1173 .maxlen = 2*sizeof(int), 1174 .mode = 0444, 1175 .proc_handler = &proc_dointvec, 1176 }, 1177 { 1178 .ctl_name = FS_STATINODE, 1179 .procname = "inode-state", 1180 .data = &inodes_stat, 1181 .maxlen = 7*sizeof(int), 1182 .mode = 0444, 1183 .proc_handler = &proc_dointvec, 1184 }, 1185 { 1186 .procname = "file-nr", 1187 .data = &files_stat, 1188 .maxlen = 3*sizeof(int), 1189 .mode = 0444, 1190 .proc_handler = &proc_nr_files, 1191 }, 1192 { 1193 .ctl_name = FS_MAXFILE, 1194 .procname = "file-max", 1195 .data = &files_stat.max_files, 1196 .maxlen = sizeof(int), 1197 .mode = 0644, 1198 .proc_handler = &proc_dointvec, 1199 }, 1200 { 1201 .ctl_name = FS_DENTRY, 1202 .procname = "dentry-state", 1203 .data = &dentry_stat, 1204 .maxlen = 6*sizeof(int), 1205 .mode = 0444, 1206 .proc_handler = &proc_dointvec, 1207 }, 1208 { 1209 .ctl_name = FS_OVERFLOWUID, 1210 .procname = "overflowuid", 1211 .data = &fs_overflowuid, 1212 .maxlen = sizeof(int), 1213 .mode = 0644, 1214 .proc_handler = &proc_dointvec_minmax, 1215 .strategy = &sysctl_intvec, 1216 .extra1 = &minolduid, 1217 .extra2 = &maxolduid, 1218 }, 1219 { 1220 .ctl_name = FS_OVERFLOWGID, 1221 .procname = "overflowgid", 1222 .data = &fs_overflowgid, 1223 .maxlen = sizeof(int), 1224 .mode = 0644, 1225 .proc_handler = &proc_dointvec_minmax, 1226 .strategy = &sysctl_intvec, 1227 .extra1 = &minolduid, 1228 .extra2 = &maxolduid, 1229 }, 1230 { 1231 .ctl_name = FS_LEASES, 1232 .procname = "leases-enable", 1233 .data = &leases_enable, 1234 .maxlen = sizeof(int), 1235 .mode = 0644, 1236 .proc_handler = &proc_dointvec, 1237 }, 1238 #ifdef CONFIG_DNOTIFY 1239 { 1240 .ctl_name = FS_DIR_NOTIFY, 1241 .procname = "dir-notify-enable", 1242 .data = &dir_notify_enable, 1243 .maxlen = sizeof(int), 1244 .mode = 0644, 1245 .proc_handler = &proc_dointvec, 1246 }, 1247 #endif 1248 #ifdef CONFIG_MMU 1249 { 1250 .ctl_name = FS_LEASE_TIME, 1251 .procname = "lease-break-time", 1252 .data = &lease_break_time, 1253 .maxlen = sizeof(int), 1254 .mode = 0644, 1255 .proc_handler = &proc_dointvec_minmax, 1256 .strategy = &sysctl_intvec, 1257 .extra1 = &zero, 1258 .extra2 = &two, 1259 }, 1260 { 1261 .procname = "aio-nr", 1262 .data = &aio_nr, 1263 .maxlen = sizeof(aio_nr), 1264 .mode = 0444, 1265 .proc_handler = &proc_doulongvec_minmax, 1266 }, 1267 { 1268 .procname = "aio-max-nr", 1269 .data = &aio_max_nr, 1270 .maxlen = sizeof(aio_max_nr), 1271 .mode = 0644, 1272 .proc_handler = &proc_doulongvec_minmax, 1273 }, 1274 #ifdef CONFIG_INOTIFY_USER 1275 { 1276 .ctl_name = FS_INOTIFY, 1277 .procname = "inotify", 1278 .mode = 0555, 1279 .child = inotify_table, 1280 }, 1281 #endif 1282 #endif 1283 { 1284 .ctl_name = KERN_SETUID_DUMPABLE, 1285 .procname = "suid_dumpable", 1286 .data = &suid_dumpable, 1287 .maxlen = sizeof(int), 1288 .mode = 0644, 1289 .proc_handler = &proc_dointvec, 1290 }, 1291 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) 1292 { 1293 .ctl_name = CTL_UNNUMBERED, 1294 .procname = "binfmt_misc", 1295 .mode = 0555, 1296 .child = binfmt_misc_table, 1297 }, 1298 #endif 1299 /* 1300 * NOTE: do not add new entries to this table unless you have read 1301 * Documentation/sysctl/ctl_unnumbered.txt 1302 */ 1303 { .ctl_name = 0 } 1304 }; 1305 1306 static struct ctl_table debug_table[] = { 1307 #if defined(CONFIG_X86) || defined(CONFIG_PPC) 1308 { 1309 .ctl_name = CTL_UNNUMBERED, 1310 .procname = "exception-trace", 1311 .data = &show_unhandled_signals, 1312 .maxlen = sizeof(int), 1313 .mode = 0644, 1314 .proc_handler = proc_dointvec 1315 }, 1316 #endif 1317 { .ctl_name = 0 } 1318 }; 1319 1320 static struct ctl_table dev_table[] = { 1321 { .ctl_name = 0 } 1322 }; 1323 1324 static DEFINE_SPINLOCK(sysctl_lock); 1325 1326 /* called under sysctl_lock */ 1327 static int use_table(struct ctl_table_header *p) 1328 { 1329 if (unlikely(p->unregistering)) 1330 return 0; 1331 p->used++; 1332 return 1; 1333 } 1334 1335 /* called under sysctl_lock */ 1336 static void unuse_table(struct ctl_table_header *p) 1337 { 1338 if (!--p->used) 1339 if (unlikely(p->unregistering)) 1340 complete(p->unregistering); 1341 } 1342 1343 /* called under sysctl_lock, will reacquire if has to wait */ 1344 static void start_unregistering(struct ctl_table_header *p) 1345 { 1346 /* 1347 * if p->used is 0, nobody will ever touch that entry again; 1348 * we'll eliminate all paths to it before dropping sysctl_lock 1349 */ 1350 if (unlikely(p->used)) { 1351 struct completion wait; 1352 init_completion(&wait); 1353 p->unregistering = &wait; 1354 spin_unlock(&sysctl_lock); 1355 wait_for_completion(&wait); 1356 spin_lock(&sysctl_lock); 1357 } 1358 /* 1359 * do not remove from the list until nobody holds it; walking the 1360 * list in do_sysctl() relies on that. 1361 */ 1362 list_del_init(&p->ctl_entry); 1363 } 1364 1365 void sysctl_head_finish(struct ctl_table_header *head) 1366 { 1367 if (!head) 1368 return; 1369 spin_lock(&sysctl_lock); 1370 unuse_table(head); 1371 spin_unlock(&sysctl_lock); 1372 } 1373 1374 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev) 1375 { 1376 struct ctl_table_header *head; 1377 struct list_head *tmp; 1378 spin_lock(&sysctl_lock); 1379 if (prev) { 1380 tmp = &prev->ctl_entry; 1381 unuse_table(prev); 1382 goto next; 1383 } 1384 tmp = &root_table_header.ctl_entry; 1385 for (;;) { 1386 head = list_entry(tmp, struct ctl_table_header, ctl_entry); 1387 1388 if (!use_table(head)) 1389 goto next; 1390 spin_unlock(&sysctl_lock); 1391 return head; 1392 next: 1393 tmp = tmp->next; 1394 if (tmp == &root_table_header.ctl_entry) 1395 break; 1396 } 1397 spin_unlock(&sysctl_lock); 1398 return NULL; 1399 } 1400 1401 #ifdef CONFIG_SYSCTL_SYSCALL 1402 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, 1403 void __user *newval, size_t newlen) 1404 { 1405 struct ctl_table_header *head; 1406 int error = -ENOTDIR; 1407 1408 if (nlen <= 0 || nlen >= CTL_MAXNAME) 1409 return -ENOTDIR; 1410 if (oldval) { 1411 int old_len; 1412 if (!oldlenp || get_user(old_len, oldlenp)) 1413 return -EFAULT; 1414 } 1415 1416 for (head = sysctl_head_next(NULL); head; 1417 head = sysctl_head_next(head)) { 1418 error = parse_table(name, nlen, oldval, oldlenp, 1419 newval, newlen, head->ctl_table); 1420 if (error != -ENOTDIR) { 1421 sysctl_head_finish(head); 1422 break; 1423 } 1424 } 1425 return error; 1426 } 1427 1428 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 1429 { 1430 struct __sysctl_args tmp; 1431 int error; 1432 1433 if (copy_from_user(&tmp, args, sizeof(tmp))) 1434 return -EFAULT; 1435 1436 error = deprecated_sysctl_warning(&tmp); 1437 if (error) 1438 goto out; 1439 1440 lock_kernel(); 1441 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp, 1442 tmp.newval, tmp.newlen); 1443 unlock_kernel(); 1444 out: 1445 return error; 1446 } 1447 #endif /* CONFIG_SYSCTL_SYSCALL */ 1448 1449 /* 1450 * sysctl_perm does NOT grant the superuser all rights automatically, because 1451 * some sysctl variables are readonly even to root. 1452 */ 1453 1454 static int test_perm(int mode, int op) 1455 { 1456 if (!current->euid) 1457 mode >>= 6; 1458 else if (in_egroup_p(0)) 1459 mode >>= 3; 1460 if ((mode & op & 0007) == op) 1461 return 0; 1462 return -EACCES; 1463 } 1464 1465 int sysctl_perm(struct ctl_table *table, int op) 1466 { 1467 int error; 1468 error = security_sysctl(table, op); 1469 if (error) 1470 return error; 1471 return test_perm(table->mode, op); 1472 } 1473 1474 #ifdef CONFIG_SYSCTL_SYSCALL 1475 static int parse_table(int __user *name, int nlen, 1476 void __user *oldval, size_t __user *oldlenp, 1477 void __user *newval, size_t newlen, 1478 struct ctl_table *table) 1479 { 1480 int n; 1481 repeat: 1482 if (!nlen) 1483 return -ENOTDIR; 1484 if (get_user(n, name)) 1485 return -EFAULT; 1486 for ( ; table->ctl_name || table->procname; table++) { 1487 if (!table->ctl_name) 1488 continue; 1489 if (n == table->ctl_name) { 1490 int error; 1491 if (table->child) { 1492 if (sysctl_perm(table, 001)) 1493 return -EPERM; 1494 name++; 1495 nlen--; 1496 table = table->child; 1497 goto repeat; 1498 } 1499 error = do_sysctl_strategy(table, name, nlen, 1500 oldval, oldlenp, 1501 newval, newlen); 1502 return error; 1503 } 1504 } 1505 return -ENOTDIR; 1506 } 1507 1508 /* Perform the actual read/write of a sysctl table entry. */ 1509 int do_sysctl_strategy (struct ctl_table *table, 1510 int __user *name, int nlen, 1511 void __user *oldval, size_t __user *oldlenp, 1512 void __user *newval, size_t newlen) 1513 { 1514 int op = 0, rc; 1515 1516 if (oldval) 1517 op |= 004; 1518 if (newval) 1519 op |= 002; 1520 if (sysctl_perm(table, op)) 1521 return -EPERM; 1522 1523 if (table->strategy) { 1524 rc = table->strategy(table, name, nlen, oldval, oldlenp, 1525 newval, newlen); 1526 if (rc < 0) 1527 return rc; 1528 if (rc > 0) 1529 return 0; 1530 } 1531 1532 /* If there is no strategy routine, or if the strategy returns 1533 * zero, proceed with automatic r/w */ 1534 if (table->data && table->maxlen) { 1535 rc = sysctl_data(table, name, nlen, oldval, oldlenp, 1536 newval, newlen); 1537 if (rc < 0) 1538 return rc; 1539 } 1540 return 0; 1541 } 1542 #endif /* CONFIG_SYSCTL_SYSCALL */ 1543 1544 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table) 1545 { 1546 for (; table->ctl_name || table->procname; table++) { 1547 table->parent = parent; 1548 if (table->child) 1549 sysctl_set_parent(table, table->child); 1550 } 1551 } 1552 1553 static __init int sysctl_init(void) 1554 { 1555 int err; 1556 sysctl_set_parent(NULL, root_table); 1557 err = sysctl_check_table(root_table); 1558 return 0; 1559 } 1560 1561 core_initcall(sysctl_init); 1562 1563 /** 1564 * register_sysctl_table - register a sysctl hierarchy 1565 * @table: the top-level table structure 1566 * 1567 * Register a sysctl table hierarchy. @table should be a filled in ctl_table 1568 * array. An entry with a ctl_name of 0 terminates the table. 1569 * 1570 * The members of the &struct ctl_table structure are used as follows: 1571 * 1572 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number 1573 * must be unique within that level of sysctl 1574 * 1575 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not 1576 * enter a sysctl file 1577 * 1578 * data - a pointer to data for use by proc_handler 1579 * 1580 * maxlen - the maximum size in bytes of the data 1581 * 1582 * mode - the file permissions for the /proc/sys file, and for sysctl(2) 1583 * 1584 * child - a pointer to the child sysctl table if this entry is a directory, or 1585 * %NULL. 1586 * 1587 * proc_handler - the text handler routine (described below) 1588 * 1589 * strategy - the strategy routine (described below) 1590 * 1591 * de - for internal use by the sysctl routines 1592 * 1593 * extra1, extra2 - extra pointers usable by the proc handler routines 1594 * 1595 * Leaf nodes in the sysctl tree will be represented by a single file 1596 * under /proc; non-leaf nodes will be represented by directories. 1597 * 1598 * sysctl(2) can automatically manage read and write requests through 1599 * the sysctl table. The data and maxlen fields of the ctl_table 1600 * struct enable minimal validation of the values being written to be 1601 * performed, and the mode field allows minimal authentication. 1602 * 1603 * More sophisticated management can be enabled by the provision of a 1604 * strategy routine with the table entry. This will be called before 1605 * any automatic read or write of the data is performed. 1606 * 1607 * The strategy routine may return 1608 * 1609 * < 0 - Error occurred (error is passed to user process) 1610 * 1611 * 0 - OK - proceed with automatic read or write. 1612 * 1613 * > 0 - OK - read or write has been done by the strategy routine, so 1614 * return immediately. 1615 * 1616 * There must be a proc_handler routine for any terminal nodes 1617 * mirrored under /proc/sys (non-terminals are handled by a built-in 1618 * directory handler). Several default handlers are available to 1619 * cover common cases - 1620 * 1621 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(), 1622 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 1623 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax() 1624 * 1625 * It is the handler's job to read the input buffer from user memory 1626 * and process it. The handler should return 0 on success. 1627 * 1628 * This routine returns %NULL on a failure to register, and a pointer 1629 * to the table header on success. 1630 */ 1631 struct ctl_table_header *register_sysctl_table(struct ctl_table * table) 1632 { 1633 struct ctl_table_header *tmp; 1634 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL); 1635 if (!tmp) 1636 return NULL; 1637 tmp->ctl_table = table; 1638 INIT_LIST_HEAD(&tmp->ctl_entry); 1639 tmp->used = 0; 1640 tmp->unregistering = NULL; 1641 sysctl_set_parent(NULL, table); 1642 if (sysctl_check_table(tmp->ctl_table)) { 1643 kfree(tmp); 1644 return NULL; 1645 } 1646 spin_lock(&sysctl_lock); 1647 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry); 1648 spin_unlock(&sysctl_lock); 1649 return tmp; 1650 } 1651 1652 /** 1653 * unregister_sysctl_table - unregister a sysctl table hierarchy 1654 * @header: the header returned from register_sysctl_table 1655 * 1656 * Unregisters the sysctl table and all children. proc entries may not 1657 * actually be removed until they are no longer used by anyone. 1658 */ 1659 void unregister_sysctl_table(struct ctl_table_header * header) 1660 { 1661 might_sleep(); 1662 1663 if (header == NULL) 1664 return; 1665 1666 spin_lock(&sysctl_lock); 1667 start_unregistering(header); 1668 spin_unlock(&sysctl_lock); 1669 kfree(header); 1670 } 1671 1672 #else /* !CONFIG_SYSCTL */ 1673 struct ctl_table_header *register_sysctl_table(struct ctl_table * table) 1674 { 1675 return NULL; 1676 } 1677 1678 void unregister_sysctl_table(struct ctl_table_header * table) 1679 { 1680 } 1681 1682 #endif /* CONFIG_SYSCTL */ 1683 1684 /* 1685 * /proc/sys support 1686 */ 1687 1688 #ifdef CONFIG_PROC_SYSCTL 1689 1690 static int _proc_do_string(void* data, int maxlen, int write, 1691 struct file *filp, void __user *buffer, 1692 size_t *lenp, loff_t *ppos) 1693 { 1694 size_t len; 1695 char __user *p; 1696 char c; 1697 1698 if (!data || !maxlen || !*lenp) { 1699 *lenp = 0; 1700 return 0; 1701 } 1702 1703 if (write) { 1704 len = 0; 1705 p = buffer; 1706 while (len < *lenp) { 1707 if (get_user(c, p++)) 1708 return -EFAULT; 1709 if (c == 0 || c == '\n') 1710 break; 1711 len++; 1712 } 1713 if (len >= maxlen) 1714 len = maxlen-1; 1715 if(copy_from_user(data, buffer, len)) 1716 return -EFAULT; 1717 ((char *) data)[len] = 0; 1718 *ppos += *lenp; 1719 } else { 1720 len = strlen(data); 1721 if (len > maxlen) 1722 len = maxlen; 1723 1724 if (*ppos > len) { 1725 *lenp = 0; 1726 return 0; 1727 } 1728 1729 data += *ppos; 1730 len -= *ppos; 1731 1732 if (len > *lenp) 1733 len = *lenp; 1734 if (len) 1735 if(copy_to_user(buffer, data, len)) 1736 return -EFAULT; 1737 if (len < *lenp) { 1738 if(put_user('\n', ((char __user *) buffer) + len)) 1739 return -EFAULT; 1740 len++; 1741 } 1742 *lenp = len; 1743 *ppos += len; 1744 } 1745 return 0; 1746 } 1747 1748 /** 1749 * proc_dostring - read a string sysctl 1750 * @table: the sysctl table 1751 * @write: %TRUE if this is a write to the sysctl file 1752 * @filp: the file structure 1753 * @buffer: the user buffer 1754 * @lenp: the size of the user buffer 1755 * @ppos: file position 1756 * 1757 * Reads/writes a string from/to the user buffer. If the kernel 1758 * buffer provided is not large enough to hold the string, the 1759 * string is truncated. The copied string is %NULL-terminated. 1760 * If the string is being read by the user process, it is copied 1761 * and a newline '\n' is added. It is truncated if the buffer is 1762 * not large enough. 1763 * 1764 * Returns 0 on success. 1765 */ 1766 int proc_dostring(struct ctl_table *table, int write, struct file *filp, 1767 void __user *buffer, size_t *lenp, loff_t *ppos) 1768 { 1769 return _proc_do_string(table->data, table->maxlen, write, filp, 1770 buffer, lenp, ppos); 1771 } 1772 1773 1774 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp, 1775 int *valp, 1776 int write, void *data) 1777 { 1778 if (write) { 1779 *valp = *negp ? -*lvalp : *lvalp; 1780 } else { 1781 int val = *valp; 1782 if (val < 0) { 1783 *negp = -1; 1784 *lvalp = (unsigned long)-val; 1785 } else { 1786 *negp = 0; 1787 *lvalp = (unsigned long)val; 1788 } 1789 } 1790 return 0; 1791 } 1792 1793 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table, 1794 int write, struct file *filp, void __user *buffer, 1795 size_t *lenp, loff_t *ppos, 1796 int (*conv)(int *negp, unsigned long *lvalp, int *valp, 1797 int write, void *data), 1798 void *data) 1799 { 1800 #define TMPBUFLEN 21 1801 int *i, vleft, first=1, neg, val; 1802 unsigned long lval; 1803 size_t left, len; 1804 1805 char buf[TMPBUFLEN], *p; 1806 char __user *s = buffer; 1807 1808 if (!tbl_data || !table->maxlen || !*lenp || 1809 (*ppos && !write)) { 1810 *lenp = 0; 1811 return 0; 1812 } 1813 1814 i = (int *) tbl_data; 1815 vleft = table->maxlen / sizeof(*i); 1816 left = *lenp; 1817 1818 if (!conv) 1819 conv = do_proc_dointvec_conv; 1820 1821 for (; left && vleft--; i++, first=0) { 1822 if (write) { 1823 while (left) { 1824 char c; 1825 if (get_user(c, s)) 1826 return -EFAULT; 1827 if (!isspace(c)) 1828 break; 1829 left--; 1830 s++; 1831 } 1832 if (!left) 1833 break; 1834 neg = 0; 1835 len = left; 1836 if (len > sizeof(buf) - 1) 1837 len = sizeof(buf) - 1; 1838 if (copy_from_user(buf, s, len)) 1839 return -EFAULT; 1840 buf[len] = 0; 1841 p = buf; 1842 if (*p == '-' && left > 1) { 1843 neg = 1; 1844 p++; 1845 } 1846 if (*p < '0' || *p > '9') 1847 break; 1848 1849 lval = simple_strtoul(p, &p, 0); 1850 1851 len = p-buf; 1852 if ((len < left) && *p && !isspace(*p)) 1853 break; 1854 if (neg) 1855 val = -val; 1856 s += len; 1857 left -= len; 1858 1859 if (conv(&neg, &lval, i, 1, data)) 1860 break; 1861 } else { 1862 p = buf; 1863 if (!first) 1864 *p++ = '\t'; 1865 1866 if (conv(&neg, &lval, i, 0, data)) 1867 break; 1868 1869 sprintf(p, "%s%lu", neg ? "-" : "", lval); 1870 len = strlen(buf); 1871 if (len > left) 1872 len = left; 1873 if(copy_to_user(s, buf, len)) 1874 return -EFAULT; 1875 left -= len; 1876 s += len; 1877 } 1878 } 1879 1880 if (!write && !first && left) { 1881 if(put_user('\n', s)) 1882 return -EFAULT; 1883 left--, s++; 1884 } 1885 if (write) { 1886 while (left) { 1887 char c; 1888 if (get_user(c, s++)) 1889 return -EFAULT; 1890 if (!isspace(c)) 1891 break; 1892 left--; 1893 } 1894 } 1895 if (write && first) 1896 return -EINVAL; 1897 *lenp -= left; 1898 *ppos += *lenp; 1899 return 0; 1900 #undef TMPBUFLEN 1901 } 1902 1903 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp, 1904 void __user *buffer, size_t *lenp, loff_t *ppos, 1905 int (*conv)(int *negp, unsigned long *lvalp, int *valp, 1906 int write, void *data), 1907 void *data) 1908 { 1909 return __do_proc_dointvec(table->data, table, write, filp, 1910 buffer, lenp, ppos, conv, data); 1911 } 1912 1913 /** 1914 * proc_dointvec - read a vector of integers 1915 * @table: the sysctl table 1916 * @write: %TRUE if this is a write to the sysctl file 1917 * @filp: the file structure 1918 * @buffer: the user buffer 1919 * @lenp: the size of the user buffer 1920 * @ppos: file position 1921 * 1922 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 1923 * values from/to the user buffer, treated as an ASCII string. 1924 * 1925 * Returns 0 on success. 1926 */ 1927 int proc_dointvec(struct ctl_table *table, int write, struct file *filp, 1928 void __user *buffer, size_t *lenp, loff_t *ppos) 1929 { 1930 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1931 NULL,NULL); 1932 } 1933 1934 #define OP_SET 0 1935 #define OP_AND 1 1936 #define OP_OR 2 1937 1938 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp, 1939 int *valp, 1940 int write, void *data) 1941 { 1942 int op = *(int *)data; 1943 if (write) { 1944 int val = *negp ? -*lvalp : *lvalp; 1945 switch(op) { 1946 case OP_SET: *valp = val; break; 1947 case OP_AND: *valp &= val; break; 1948 case OP_OR: *valp |= val; break; 1949 } 1950 } else { 1951 int val = *valp; 1952 if (val < 0) { 1953 *negp = -1; 1954 *lvalp = (unsigned long)-val; 1955 } else { 1956 *negp = 0; 1957 *lvalp = (unsigned long)val; 1958 } 1959 } 1960 return 0; 1961 } 1962 1963 #ifdef CONFIG_SECURITY_CAPABILITIES 1964 /* 1965 * init may raise the set. 1966 */ 1967 1968 int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp, 1969 void __user *buffer, size_t *lenp, loff_t *ppos) 1970 { 1971 int op; 1972 1973 if (write && !capable(CAP_SYS_MODULE)) { 1974 return -EPERM; 1975 } 1976 1977 op = is_global_init(current) ? OP_SET : OP_AND; 1978 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1979 do_proc_dointvec_bset_conv,&op); 1980 } 1981 #endif /* def CONFIG_SECURITY_CAPABILITIES */ 1982 1983 /* 1984 * Taint values can only be increased 1985 */ 1986 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp, 1987 void __user *buffer, size_t *lenp, loff_t *ppos) 1988 { 1989 int op; 1990 1991 if (write && !capable(CAP_SYS_ADMIN)) 1992 return -EPERM; 1993 1994 op = OP_OR; 1995 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1996 do_proc_dointvec_bset_conv,&op); 1997 } 1998 1999 struct do_proc_dointvec_minmax_conv_param { 2000 int *min; 2001 int *max; 2002 }; 2003 2004 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 2005 int *valp, 2006 int write, void *data) 2007 { 2008 struct do_proc_dointvec_minmax_conv_param *param = data; 2009 if (write) { 2010 int val = *negp ? -*lvalp : *lvalp; 2011 if ((param->min && *param->min > val) || 2012 (param->max && *param->max < val)) 2013 return -EINVAL; 2014 *valp = val; 2015 } else { 2016 int val = *valp; 2017 if (val < 0) { 2018 *negp = -1; 2019 *lvalp = (unsigned long)-val; 2020 } else { 2021 *negp = 0; 2022 *lvalp = (unsigned long)val; 2023 } 2024 } 2025 return 0; 2026 } 2027 2028 /** 2029 * proc_dointvec_minmax - read a vector of integers with min/max values 2030 * @table: the sysctl table 2031 * @write: %TRUE if this is a write to the sysctl file 2032 * @filp: the file structure 2033 * @buffer: the user buffer 2034 * @lenp: the size of the user buffer 2035 * @ppos: file position 2036 * 2037 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2038 * values from/to the user buffer, treated as an ASCII string. 2039 * 2040 * This routine will ensure the values are within the range specified by 2041 * table->extra1 (min) and table->extra2 (max). 2042 * 2043 * Returns 0 on success. 2044 */ 2045 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp, 2046 void __user *buffer, size_t *lenp, loff_t *ppos) 2047 { 2048 struct do_proc_dointvec_minmax_conv_param param = { 2049 .min = (int *) table->extra1, 2050 .max = (int *) table->extra2, 2051 }; 2052 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 2053 do_proc_dointvec_minmax_conv, ¶m); 2054 } 2055 2056 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write, 2057 struct file *filp, 2058 void __user *buffer, 2059 size_t *lenp, loff_t *ppos, 2060 unsigned long convmul, 2061 unsigned long convdiv) 2062 { 2063 #define TMPBUFLEN 21 2064 unsigned long *i, *min, *max, val; 2065 int vleft, first=1, neg; 2066 size_t len, left; 2067 char buf[TMPBUFLEN], *p; 2068 char __user *s = buffer; 2069 2070 if (!data || !table->maxlen || !*lenp || 2071 (*ppos && !write)) { 2072 *lenp = 0; 2073 return 0; 2074 } 2075 2076 i = (unsigned long *) data; 2077 min = (unsigned long *) table->extra1; 2078 max = (unsigned long *) table->extra2; 2079 vleft = table->maxlen / sizeof(unsigned long); 2080 left = *lenp; 2081 2082 for (; left && vleft--; i++, min++, max++, first=0) { 2083 if (write) { 2084 while (left) { 2085 char c; 2086 if (get_user(c, s)) 2087 return -EFAULT; 2088 if (!isspace(c)) 2089 break; 2090 left--; 2091 s++; 2092 } 2093 if (!left) 2094 break; 2095 neg = 0; 2096 len = left; 2097 if (len > TMPBUFLEN-1) 2098 len = TMPBUFLEN-1; 2099 if (copy_from_user(buf, s, len)) 2100 return -EFAULT; 2101 buf[len] = 0; 2102 p = buf; 2103 if (*p == '-' && left > 1) { 2104 neg = 1; 2105 p++; 2106 } 2107 if (*p < '0' || *p > '9') 2108 break; 2109 val = simple_strtoul(p, &p, 0) * convmul / convdiv ; 2110 len = p-buf; 2111 if ((len < left) && *p && !isspace(*p)) 2112 break; 2113 if (neg) 2114 val = -val; 2115 s += len; 2116 left -= len; 2117 2118 if(neg) 2119 continue; 2120 if ((min && val < *min) || (max && val > *max)) 2121 continue; 2122 *i = val; 2123 } else { 2124 p = buf; 2125 if (!first) 2126 *p++ = '\t'; 2127 sprintf(p, "%lu", convdiv * (*i) / convmul); 2128 len = strlen(buf); 2129 if (len > left) 2130 len = left; 2131 if(copy_to_user(s, buf, len)) 2132 return -EFAULT; 2133 left -= len; 2134 s += len; 2135 } 2136 } 2137 2138 if (!write && !first && left) { 2139 if(put_user('\n', s)) 2140 return -EFAULT; 2141 left--, s++; 2142 } 2143 if (write) { 2144 while (left) { 2145 char c; 2146 if (get_user(c, s++)) 2147 return -EFAULT; 2148 if (!isspace(c)) 2149 break; 2150 left--; 2151 } 2152 } 2153 if (write && first) 2154 return -EINVAL; 2155 *lenp -= left; 2156 *ppos += *lenp; 2157 return 0; 2158 #undef TMPBUFLEN 2159 } 2160 2161 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write, 2162 struct file *filp, 2163 void __user *buffer, 2164 size_t *lenp, loff_t *ppos, 2165 unsigned long convmul, 2166 unsigned long convdiv) 2167 { 2168 return __do_proc_doulongvec_minmax(table->data, table, write, 2169 filp, buffer, lenp, ppos, convmul, convdiv); 2170 } 2171 2172 /** 2173 * proc_doulongvec_minmax - read a vector of long integers with min/max values 2174 * @table: the sysctl table 2175 * @write: %TRUE if this is a write to the sysctl file 2176 * @filp: the file structure 2177 * @buffer: the user buffer 2178 * @lenp: the size of the user buffer 2179 * @ppos: file position 2180 * 2181 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 2182 * values from/to the user buffer, treated as an ASCII string. 2183 * 2184 * This routine will ensure the values are within the range specified by 2185 * table->extra1 (min) and table->extra2 (max). 2186 * 2187 * Returns 0 on success. 2188 */ 2189 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp, 2190 void __user *buffer, size_t *lenp, loff_t *ppos) 2191 { 2192 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l); 2193 } 2194 2195 /** 2196 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values 2197 * @table: the sysctl table 2198 * @write: %TRUE if this is a write to the sysctl file 2199 * @filp: the file structure 2200 * @buffer: the user buffer 2201 * @lenp: the size of the user buffer 2202 * @ppos: file position 2203 * 2204 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 2205 * values from/to the user buffer, treated as an ASCII string. The values 2206 * are treated as milliseconds, and converted to jiffies when they are stored. 2207 * 2208 * This routine will ensure the values are within the range specified by 2209 * table->extra1 (min) and table->extra2 (max). 2210 * 2211 * Returns 0 on success. 2212 */ 2213 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write, 2214 struct file *filp, 2215 void __user *buffer, 2216 size_t *lenp, loff_t *ppos) 2217 { 2218 return do_proc_doulongvec_minmax(table, write, filp, buffer, 2219 lenp, ppos, HZ, 1000l); 2220 } 2221 2222 2223 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp, 2224 int *valp, 2225 int write, void *data) 2226 { 2227 if (write) { 2228 if (*lvalp > LONG_MAX / HZ) 2229 return 1; 2230 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ); 2231 } else { 2232 int val = *valp; 2233 unsigned long lval; 2234 if (val < 0) { 2235 *negp = -1; 2236 lval = (unsigned long)-val; 2237 } else { 2238 *negp = 0; 2239 lval = (unsigned long)val; 2240 } 2241 *lvalp = lval / HZ; 2242 } 2243 return 0; 2244 } 2245 2246 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp, 2247 int *valp, 2248 int write, void *data) 2249 { 2250 if (write) { 2251 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ) 2252 return 1; 2253 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp); 2254 } else { 2255 int val = *valp; 2256 unsigned long lval; 2257 if (val < 0) { 2258 *negp = -1; 2259 lval = (unsigned long)-val; 2260 } else { 2261 *negp = 0; 2262 lval = (unsigned long)val; 2263 } 2264 *lvalp = jiffies_to_clock_t(lval); 2265 } 2266 return 0; 2267 } 2268 2269 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp, 2270 int *valp, 2271 int write, void *data) 2272 { 2273 if (write) { 2274 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp); 2275 } else { 2276 int val = *valp; 2277 unsigned long lval; 2278 if (val < 0) { 2279 *negp = -1; 2280 lval = (unsigned long)-val; 2281 } else { 2282 *negp = 0; 2283 lval = (unsigned long)val; 2284 } 2285 *lvalp = jiffies_to_msecs(lval); 2286 } 2287 return 0; 2288 } 2289 2290 /** 2291 * proc_dointvec_jiffies - read a vector of integers as seconds 2292 * @table: the sysctl table 2293 * @write: %TRUE if this is a write to the sysctl file 2294 * @filp: the file structure 2295 * @buffer: the user buffer 2296 * @lenp: the size of the user buffer 2297 * @ppos: file position 2298 * 2299 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2300 * values from/to the user buffer, treated as an ASCII string. 2301 * The values read are assumed to be in seconds, and are converted into 2302 * jiffies. 2303 * 2304 * Returns 0 on success. 2305 */ 2306 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp, 2307 void __user *buffer, size_t *lenp, loff_t *ppos) 2308 { 2309 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2310 do_proc_dointvec_jiffies_conv,NULL); 2311 } 2312 2313 /** 2314 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds 2315 * @table: the sysctl table 2316 * @write: %TRUE if this is a write to the sysctl file 2317 * @filp: the file structure 2318 * @buffer: the user buffer 2319 * @lenp: the size of the user buffer 2320 * @ppos: pointer to the file position 2321 * 2322 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2323 * values from/to the user buffer, treated as an ASCII string. 2324 * The values read are assumed to be in 1/USER_HZ seconds, and 2325 * are converted into jiffies. 2326 * 2327 * Returns 0 on success. 2328 */ 2329 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp, 2330 void __user *buffer, size_t *lenp, loff_t *ppos) 2331 { 2332 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2333 do_proc_dointvec_userhz_jiffies_conv,NULL); 2334 } 2335 2336 /** 2337 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds 2338 * @table: the sysctl table 2339 * @write: %TRUE if this is a write to the sysctl file 2340 * @filp: the file structure 2341 * @buffer: the user buffer 2342 * @lenp: the size of the user buffer 2343 * @ppos: file position 2344 * @ppos: the current position in the file 2345 * 2346 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2347 * values from/to the user buffer, treated as an ASCII string. 2348 * The values read are assumed to be in 1/1000 seconds, and 2349 * are converted into jiffies. 2350 * 2351 * Returns 0 on success. 2352 */ 2353 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp, 2354 void __user *buffer, size_t *lenp, loff_t *ppos) 2355 { 2356 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 2357 do_proc_dointvec_ms_jiffies_conv, NULL); 2358 } 2359 2360 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp, 2361 void __user *buffer, size_t *lenp, loff_t *ppos) 2362 { 2363 struct pid *new_pid; 2364 pid_t tmp; 2365 int r; 2366 2367 tmp = pid_nr_ns(cad_pid, current->nsproxy->pid_ns); 2368 2369 r = __do_proc_dointvec(&tmp, table, write, filp, buffer, 2370 lenp, ppos, NULL, NULL); 2371 if (r || !write) 2372 return r; 2373 2374 new_pid = find_get_pid(tmp); 2375 if (!new_pid) 2376 return -ESRCH; 2377 2378 put_pid(xchg(&cad_pid, new_pid)); 2379 return 0; 2380 } 2381 2382 #else /* CONFIG_PROC_FS */ 2383 2384 int proc_dostring(struct ctl_table *table, int write, struct file *filp, 2385 void __user *buffer, size_t *lenp, loff_t *ppos) 2386 { 2387 return -ENOSYS; 2388 } 2389 2390 int proc_dointvec(struct ctl_table *table, int write, struct file *filp, 2391 void __user *buffer, size_t *lenp, loff_t *ppos) 2392 { 2393 return -ENOSYS; 2394 } 2395 2396 int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp, 2397 void __user *buffer, size_t *lenp, loff_t *ppos) 2398 { 2399 return -ENOSYS; 2400 } 2401 2402 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp, 2403 void __user *buffer, size_t *lenp, loff_t *ppos) 2404 { 2405 return -ENOSYS; 2406 } 2407 2408 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp, 2409 void __user *buffer, size_t *lenp, loff_t *ppos) 2410 { 2411 return -ENOSYS; 2412 } 2413 2414 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp, 2415 void __user *buffer, size_t *lenp, loff_t *ppos) 2416 { 2417 return -ENOSYS; 2418 } 2419 2420 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp, 2421 void __user *buffer, size_t *lenp, loff_t *ppos) 2422 { 2423 return -ENOSYS; 2424 } 2425 2426 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp, 2427 void __user *buffer, size_t *lenp, loff_t *ppos) 2428 { 2429 return -ENOSYS; 2430 } 2431 2432 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write, 2433 struct file *filp, 2434 void __user *buffer, 2435 size_t *lenp, loff_t *ppos) 2436 { 2437 return -ENOSYS; 2438 } 2439 2440 2441 #endif /* CONFIG_PROC_FS */ 2442 2443 2444 #ifdef CONFIG_SYSCTL_SYSCALL 2445 /* 2446 * General sysctl support routines 2447 */ 2448 2449 /* The generic sysctl data routine (used if no strategy routine supplied) */ 2450 int sysctl_data(struct ctl_table *table, int __user *name, int nlen, 2451 void __user *oldval, size_t __user *oldlenp, 2452 void __user *newval, size_t newlen) 2453 { 2454 size_t len; 2455 2456 /* Get out of I don't have a variable */ 2457 if (!table->data || !table->maxlen) 2458 return -ENOTDIR; 2459 2460 if (oldval && oldlenp) { 2461 if (get_user(len, oldlenp)) 2462 return -EFAULT; 2463 if (len) { 2464 if (len > table->maxlen) 2465 len = table->maxlen; 2466 if (copy_to_user(oldval, table->data, len)) 2467 return -EFAULT; 2468 if (put_user(len, oldlenp)) 2469 return -EFAULT; 2470 } 2471 } 2472 2473 if (newval && newlen) { 2474 if (newlen > table->maxlen) 2475 newlen = table->maxlen; 2476 2477 if (copy_from_user(table->data, newval, newlen)) 2478 return -EFAULT; 2479 } 2480 return 1; 2481 } 2482 2483 /* The generic string strategy routine: */ 2484 int sysctl_string(struct ctl_table *table, int __user *name, int nlen, 2485 void __user *oldval, size_t __user *oldlenp, 2486 void __user *newval, size_t newlen) 2487 { 2488 if (!table->data || !table->maxlen) 2489 return -ENOTDIR; 2490 2491 if (oldval && oldlenp) { 2492 size_t bufsize; 2493 if (get_user(bufsize, oldlenp)) 2494 return -EFAULT; 2495 if (bufsize) { 2496 size_t len = strlen(table->data), copied; 2497 2498 /* This shouldn't trigger for a well-formed sysctl */ 2499 if (len > table->maxlen) 2500 len = table->maxlen; 2501 2502 /* Copy up to a max of bufsize-1 bytes of the string */ 2503 copied = (len >= bufsize) ? bufsize - 1 : len; 2504 2505 if (copy_to_user(oldval, table->data, copied) || 2506 put_user(0, (char __user *)(oldval + copied))) 2507 return -EFAULT; 2508 if (put_user(len, oldlenp)) 2509 return -EFAULT; 2510 } 2511 } 2512 if (newval && newlen) { 2513 size_t len = newlen; 2514 if (len > table->maxlen) 2515 len = table->maxlen; 2516 if(copy_from_user(table->data, newval, len)) 2517 return -EFAULT; 2518 if (len == table->maxlen) 2519 len--; 2520 ((char *) table->data)[len] = 0; 2521 } 2522 return 1; 2523 } 2524 2525 /* 2526 * This function makes sure that all of the integers in the vector 2527 * are between the minimum and maximum values given in the arrays 2528 * table->extra1 and table->extra2, respectively. 2529 */ 2530 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen, 2531 void __user *oldval, size_t __user *oldlenp, 2532 void __user *newval, size_t newlen) 2533 { 2534 2535 if (newval && newlen) { 2536 int __user *vec = (int __user *) newval; 2537 int *min = (int *) table->extra1; 2538 int *max = (int *) table->extra2; 2539 size_t length; 2540 int i; 2541 2542 if (newlen % sizeof(int) != 0) 2543 return -EINVAL; 2544 2545 if (!table->extra1 && !table->extra2) 2546 return 0; 2547 2548 if (newlen > table->maxlen) 2549 newlen = table->maxlen; 2550 length = newlen / sizeof(int); 2551 2552 for (i = 0; i < length; i++) { 2553 int value; 2554 if (get_user(value, vec + i)) 2555 return -EFAULT; 2556 if (min && value < min[i]) 2557 return -EINVAL; 2558 if (max && value > max[i]) 2559 return -EINVAL; 2560 } 2561 } 2562 return 0; 2563 } 2564 2565 /* Strategy function to convert jiffies to seconds */ 2566 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen, 2567 void __user *oldval, size_t __user *oldlenp, 2568 void __user *newval, size_t newlen) 2569 { 2570 if (oldval && oldlenp) { 2571 size_t olen; 2572 2573 if (get_user(olen, oldlenp)) 2574 return -EFAULT; 2575 if (olen) { 2576 int val; 2577 2578 if (olen < sizeof(int)) 2579 return -EINVAL; 2580 2581 val = *(int *)(table->data) / HZ; 2582 if (put_user(val, (int __user *)oldval)) 2583 return -EFAULT; 2584 if (put_user(sizeof(int), oldlenp)) 2585 return -EFAULT; 2586 } 2587 } 2588 if (newval && newlen) { 2589 int new; 2590 if (newlen != sizeof(int)) 2591 return -EINVAL; 2592 if (get_user(new, (int __user *)newval)) 2593 return -EFAULT; 2594 *(int *)(table->data) = new*HZ; 2595 } 2596 return 1; 2597 } 2598 2599 /* Strategy function to convert jiffies to seconds */ 2600 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen, 2601 void __user *oldval, size_t __user *oldlenp, 2602 void __user *newval, size_t newlen) 2603 { 2604 if (oldval && oldlenp) { 2605 size_t olen; 2606 2607 if (get_user(olen, oldlenp)) 2608 return -EFAULT; 2609 if (olen) { 2610 int val; 2611 2612 if (olen < sizeof(int)) 2613 return -EINVAL; 2614 2615 val = jiffies_to_msecs(*(int *)(table->data)); 2616 if (put_user(val, (int __user *)oldval)) 2617 return -EFAULT; 2618 if (put_user(sizeof(int), oldlenp)) 2619 return -EFAULT; 2620 } 2621 } 2622 if (newval && newlen) { 2623 int new; 2624 if (newlen != sizeof(int)) 2625 return -EINVAL; 2626 if (get_user(new, (int __user *)newval)) 2627 return -EFAULT; 2628 *(int *)(table->data) = msecs_to_jiffies(new); 2629 } 2630 return 1; 2631 } 2632 2633 2634 2635 #else /* CONFIG_SYSCTL_SYSCALL */ 2636 2637 2638 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 2639 { 2640 struct __sysctl_args tmp; 2641 int error; 2642 2643 if (copy_from_user(&tmp, args, sizeof(tmp))) 2644 return -EFAULT; 2645 2646 error = deprecated_sysctl_warning(&tmp); 2647 2648 /* If no error reading the parameters then just -ENOSYS ... */ 2649 if (!error) 2650 error = -ENOSYS; 2651 2652 return error; 2653 } 2654 2655 int sysctl_data(struct ctl_table *table, int __user *name, int nlen, 2656 void __user *oldval, size_t __user *oldlenp, 2657 void __user *newval, size_t newlen) 2658 { 2659 return -ENOSYS; 2660 } 2661 2662 int sysctl_string(struct ctl_table *table, int __user *name, int nlen, 2663 void __user *oldval, size_t __user *oldlenp, 2664 void __user *newval, size_t newlen) 2665 { 2666 return -ENOSYS; 2667 } 2668 2669 int sysctl_intvec(struct 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 return -ENOSYS; 2674 } 2675 2676 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen, 2677 void __user *oldval, size_t __user *oldlenp, 2678 void __user *newval, size_t newlen) 2679 { 2680 return -ENOSYS; 2681 } 2682 2683 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen, 2684 void __user *oldval, size_t __user *oldlenp, 2685 void __user *newval, size_t newlen) 2686 { 2687 return -ENOSYS; 2688 } 2689 2690 #endif /* CONFIG_SYSCTL_SYSCALL */ 2691 2692 static int deprecated_sysctl_warning(struct __sysctl_args *args) 2693 { 2694 static int msg_count; 2695 int name[CTL_MAXNAME]; 2696 int i; 2697 2698 /* Check args->nlen. */ 2699 if (args->nlen < 0 || args->nlen > CTL_MAXNAME) 2700 return -ENOTDIR; 2701 2702 /* Read in the sysctl name for better debug message logging */ 2703 for (i = 0; i < args->nlen; i++) 2704 if (get_user(name[i], args->name + i)) 2705 return -EFAULT; 2706 2707 /* Ignore accesses to kernel.version */ 2708 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION)) 2709 return 0; 2710 2711 if (msg_count < 5) { 2712 msg_count++; 2713 printk(KERN_INFO 2714 "warning: process `%s' used the deprecated sysctl " 2715 "system call with ", current->comm); 2716 for (i = 0; i < args->nlen; i++) 2717 printk("%d.", name[i]); 2718 printk("\n"); 2719 } 2720 return 0; 2721 } 2722 2723 /* 2724 * No sense putting this after each symbol definition, twice, 2725 * exception granted :-) 2726 */ 2727 EXPORT_SYMBOL(proc_dointvec); 2728 EXPORT_SYMBOL(proc_dointvec_jiffies); 2729 EXPORT_SYMBOL(proc_dointvec_minmax); 2730 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies); 2731 EXPORT_SYMBOL(proc_dointvec_ms_jiffies); 2732 EXPORT_SYMBOL(proc_dostring); 2733 EXPORT_SYMBOL(proc_doulongvec_minmax); 2734 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax); 2735 EXPORT_SYMBOL(register_sysctl_table); 2736 EXPORT_SYMBOL(sysctl_intvec); 2737 EXPORT_SYMBOL(sysctl_jiffies); 2738 EXPORT_SYMBOL(sysctl_ms_jiffies); 2739 EXPORT_SYMBOL(sysctl_string); 2740 EXPORT_SYMBOL(sysctl_data); 2741 EXPORT_SYMBOL(unregister_sysctl_table); 2742