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/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 #if defined(CONFIG_SYSCTL) 59 60 /* External variables not in a header file. */ 61 extern int C_A_D; 62 extern int print_fatal_signals; 63 extern int sysctl_overcommit_memory; 64 extern int sysctl_overcommit_ratio; 65 extern int sysctl_panic_on_oom; 66 extern int max_threads; 67 extern int core_uses_pid; 68 extern int suid_dumpable; 69 extern char core_pattern[]; 70 extern int pid_max; 71 extern int min_free_kbytes; 72 extern int printk_ratelimit_jiffies; 73 extern int printk_ratelimit_burst; 74 extern int pid_max_min, pid_max_max; 75 extern int sysctl_drop_caches; 76 extern int percpu_pagelist_fraction; 77 extern int compat_log; 78 extern int maps_protect; 79 extern int sysctl_stat_interval; 80 extern int audit_argv_kb; 81 82 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */ 83 static int maxolduid = 65535; 84 static int minolduid; 85 static int min_percpu_pagelist_fract = 8; 86 87 static int ngroups_max = NGROUPS_MAX; 88 89 #ifdef CONFIG_KMOD 90 extern char modprobe_path[]; 91 #endif 92 #ifdef CONFIG_CHR_DEV_SG 93 extern int sg_big_buff; 94 #endif 95 96 #ifdef __sparc__ 97 extern char reboot_command []; 98 extern int stop_a_enabled; 99 extern int scons_pwroff; 100 #endif 101 102 #ifdef __hppa__ 103 extern int pwrsw_enabled; 104 extern int unaligned_enabled; 105 #endif 106 107 #ifdef CONFIG_S390 108 #ifdef CONFIG_MATHEMU 109 extern int sysctl_ieee_emulation_warnings; 110 #endif 111 extern int sysctl_userprocess_debug; 112 extern int spin_retry; 113 #endif 114 115 extern int sysctl_hz_timer; 116 117 #ifdef CONFIG_BSD_PROCESS_ACCT 118 extern int acct_parm[]; 119 #endif 120 121 #ifdef CONFIG_IA64 122 extern int no_unaligned_warning; 123 #endif 124 125 #ifdef CONFIG_RT_MUTEXES 126 extern int max_lock_depth; 127 #endif 128 129 #ifdef CONFIG_SYSCTL_SYSCALL 130 static int parse_table(int __user *, int, void __user *, size_t __user *, 131 void __user *, size_t, ctl_table *); 132 #endif 133 134 135 #ifdef CONFIG_PROC_SYSCTL 136 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp, 137 void __user *buffer, size_t *lenp, loff_t *ppos); 138 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp, 139 void __user *buffer, size_t *lenp, loff_t *ppos); 140 #endif 141 142 static ctl_table root_table[]; 143 static struct ctl_table_header root_table_header = 144 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) }; 145 146 static ctl_table kern_table[]; 147 static ctl_table vm_table[]; 148 static ctl_table fs_table[]; 149 static ctl_table debug_table[]; 150 static ctl_table dev_table[]; 151 extern ctl_table random_table[]; 152 #ifdef CONFIG_UNIX98_PTYS 153 extern ctl_table pty_table[]; 154 #endif 155 #ifdef CONFIG_INOTIFY_USER 156 extern ctl_table inotify_table[]; 157 #endif 158 159 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 160 int sysctl_legacy_va_layout; 161 #endif 162 163 extern int prove_locking; 164 extern int lock_stat; 165 166 /* The default sysctl tables: */ 167 168 static ctl_table root_table[] = { 169 { 170 .ctl_name = CTL_KERN, 171 .procname = "kernel", 172 .mode = 0555, 173 .child = kern_table, 174 }, 175 { 176 .ctl_name = CTL_VM, 177 .procname = "vm", 178 .mode = 0555, 179 .child = vm_table, 180 }, 181 #ifdef CONFIG_NET 182 { 183 .ctl_name = CTL_NET, 184 .procname = "net", 185 .mode = 0555, 186 .child = net_table, 187 }, 188 #endif 189 { 190 .ctl_name = CTL_FS, 191 .procname = "fs", 192 .mode = 0555, 193 .child = fs_table, 194 }, 195 { 196 .ctl_name = CTL_DEBUG, 197 .procname = "debug", 198 .mode = 0555, 199 .child = debug_table, 200 }, 201 { 202 .ctl_name = CTL_DEV, 203 .procname = "dev", 204 .mode = 0555, 205 .child = dev_table, 206 }, 207 /* 208 * NOTE: do not add new entries to this table unless you have read 209 * Documentation/sysctl/ctl_unnumbered.txt 210 */ 211 { .ctl_name = 0 } 212 }; 213 214 #ifdef CONFIG_SCHED_DEBUG 215 static unsigned long min_sched_granularity_ns = 100000; /* 100 usecs */ 216 static unsigned long max_sched_granularity_ns = 1000000000; /* 1 second */ 217 static unsigned long min_wakeup_granularity_ns; /* 0 usecs */ 218 static unsigned long max_wakeup_granularity_ns = 1000000000; /* 1 second */ 219 #endif 220 221 static ctl_table kern_table[] = { 222 #ifdef CONFIG_SCHED_DEBUG 223 { 224 .ctl_name = CTL_UNNUMBERED, 225 .procname = "sched_nr_latency", 226 .data = &sysctl_sched_nr_latency, 227 .maxlen = sizeof(unsigned int), 228 .mode = 0644, 229 .proc_handler = &proc_dointvec, 230 }, 231 { 232 .ctl_name = CTL_UNNUMBERED, 233 .procname = "sched_latency_ns", 234 .data = &sysctl_sched_latency, 235 .maxlen = sizeof(unsigned int), 236 .mode = 0644, 237 .proc_handler = &proc_dointvec_minmax, 238 .strategy = &sysctl_intvec, 239 .extra1 = &min_sched_granularity_ns, 240 .extra2 = &max_sched_granularity_ns, 241 }, 242 { 243 .ctl_name = CTL_UNNUMBERED, 244 .procname = "sched_wakeup_granularity_ns", 245 .data = &sysctl_sched_wakeup_granularity, 246 .maxlen = sizeof(unsigned int), 247 .mode = 0644, 248 .proc_handler = &proc_dointvec_minmax, 249 .strategy = &sysctl_intvec, 250 .extra1 = &min_wakeup_granularity_ns, 251 .extra2 = &max_wakeup_granularity_ns, 252 }, 253 { 254 .ctl_name = CTL_UNNUMBERED, 255 .procname = "sched_batch_wakeup_granularity_ns", 256 .data = &sysctl_sched_batch_wakeup_granularity, 257 .maxlen = sizeof(unsigned int), 258 .mode = 0644, 259 .proc_handler = &proc_dointvec_minmax, 260 .strategy = &sysctl_intvec, 261 .extra1 = &min_wakeup_granularity_ns, 262 .extra2 = &max_wakeup_granularity_ns, 263 }, 264 { 265 .ctl_name = CTL_UNNUMBERED, 266 .procname = "sched_child_runs_first", 267 .data = &sysctl_sched_child_runs_first, 268 .maxlen = sizeof(unsigned int), 269 .mode = 0644, 270 .proc_handler = &proc_dointvec, 271 }, 272 { 273 .ctl_name = CTL_UNNUMBERED, 274 .procname = "sched_features", 275 .data = &sysctl_sched_features, 276 .maxlen = sizeof(unsigned int), 277 .mode = 0644, 278 .proc_handler = &proc_dointvec, 279 }, 280 { 281 .ctl_name = CTL_UNNUMBERED, 282 .procname = "sched_migration_cost", 283 .data = &sysctl_sched_migration_cost, 284 .maxlen = sizeof(unsigned int), 285 .mode = 0644, 286 .proc_handler = &proc_dointvec, 287 }, 288 #endif 289 { 290 .ctl_name = CTL_UNNUMBERED, 291 .procname = "sched_compat_yield", 292 .data = &sysctl_sched_compat_yield, 293 .maxlen = sizeof(unsigned int), 294 .mode = 0644, 295 .proc_handler = &proc_dointvec, 296 }, 297 #ifdef CONFIG_PROVE_LOCKING 298 { 299 .ctl_name = CTL_UNNUMBERED, 300 .procname = "prove_locking", 301 .data = &prove_locking, 302 .maxlen = sizeof(int), 303 .mode = 0644, 304 .proc_handler = &proc_dointvec, 305 }, 306 #endif 307 #ifdef CONFIG_LOCK_STAT 308 { 309 .ctl_name = CTL_UNNUMBERED, 310 .procname = "lock_stat", 311 .data = &lock_stat, 312 .maxlen = sizeof(int), 313 .mode = 0644, 314 .proc_handler = &proc_dointvec, 315 }, 316 #endif 317 { 318 .ctl_name = KERN_PANIC, 319 .procname = "panic", 320 .data = &panic_timeout, 321 .maxlen = sizeof(int), 322 .mode = 0644, 323 .proc_handler = &proc_dointvec, 324 }, 325 { 326 .ctl_name = KERN_CORE_USES_PID, 327 .procname = "core_uses_pid", 328 .data = &core_uses_pid, 329 .maxlen = sizeof(int), 330 .mode = 0644, 331 .proc_handler = &proc_dointvec, 332 }, 333 #ifdef CONFIG_AUDITSYSCALL 334 { 335 .ctl_name = CTL_UNNUMBERED, 336 .procname = "audit_argv_kb", 337 .data = &audit_argv_kb, 338 .maxlen = sizeof(int), 339 .mode = 0644, 340 .proc_handler = &proc_dointvec, 341 }, 342 #endif 343 { 344 .ctl_name = KERN_CORE_PATTERN, 345 .procname = "core_pattern", 346 .data = core_pattern, 347 .maxlen = CORENAME_MAX_SIZE, 348 .mode = 0644, 349 .proc_handler = &proc_dostring, 350 .strategy = &sysctl_string, 351 }, 352 #ifdef CONFIG_PROC_SYSCTL 353 { 354 .ctl_name = KERN_TAINTED, 355 .procname = "tainted", 356 .data = &tainted, 357 .maxlen = sizeof(int), 358 .mode = 0644, 359 .proc_handler = &proc_dointvec_taint, 360 }, 361 #endif 362 { 363 .ctl_name = KERN_CAP_BSET, 364 .procname = "cap-bound", 365 .data = &cap_bset, 366 .maxlen = sizeof(kernel_cap_t), 367 .mode = 0600, 368 .proc_handler = &proc_dointvec_bset, 369 }, 370 #ifdef CONFIG_BLK_DEV_INITRD 371 { 372 .ctl_name = KERN_REALROOTDEV, 373 .procname = "real-root-dev", 374 .data = &real_root_dev, 375 .maxlen = sizeof(int), 376 .mode = 0644, 377 .proc_handler = &proc_dointvec, 378 }, 379 #endif 380 { 381 .ctl_name = CTL_UNNUMBERED, 382 .procname = "print-fatal-signals", 383 .data = &print_fatal_signals, 384 .maxlen = sizeof(int), 385 .mode = 0644, 386 .proc_handler = &proc_dointvec, 387 }, 388 #ifdef __sparc__ 389 { 390 .ctl_name = KERN_SPARC_REBOOT, 391 .procname = "reboot-cmd", 392 .data = reboot_command, 393 .maxlen = 256, 394 .mode = 0644, 395 .proc_handler = &proc_dostring, 396 .strategy = &sysctl_string, 397 }, 398 { 399 .ctl_name = KERN_SPARC_STOP_A, 400 .procname = "stop-a", 401 .data = &stop_a_enabled, 402 .maxlen = sizeof (int), 403 .mode = 0644, 404 .proc_handler = &proc_dointvec, 405 }, 406 { 407 .ctl_name = KERN_SPARC_SCONS_PWROFF, 408 .procname = "scons-poweroff", 409 .data = &scons_pwroff, 410 .maxlen = sizeof (int), 411 .mode = 0644, 412 .proc_handler = &proc_dointvec, 413 }, 414 #endif 415 #ifdef __hppa__ 416 { 417 .ctl_name = KERN_HPPA_PWRSW, 418 .procname = "soft-power", 419 .data = &pwrsw_enabled, 420 .maxlen = sizeof (int), 421 .mode = 0644, 422 .proc_handler = &proc_dointvec, 423 }, 424 { 425 .ctl_name = KERN_HPPA_UNALIGNED, 426 .procname = "unaligned-trap", 427 .data = &unaligned_enabled, 428 .maxlen = sizeof (int), 429 .mode = 0644, 430 .proc_handler = &proc_dointvec, 431 }, 432 #endif 433 { 434 .ctl_name = KERN_CTLALTDEL, 435 .procname = "ctrl-alt-del", 436 .data = &C_A_D, 437 .maxlen = sizeof(int), 438 .mode = 0644, 439 .proc_handler = &proc_dointvec, 440 }, 441 { 442 .ctl_name = KERN_PRINTK, 443 .procname = "printk", 444 .data = &console_loglevel, 445 .maxlen = 4*sizeof(int), 446 .mode = 0644, 447 .proc_handler = &proc_dointvec, 448 }, 449 #ifdef CONFIG_KMOD 450 { 451 .ctl_name = KERN_MODPROBE, 452 .procname = "modprobe", 453 .data = &modprobe_path, 454 .maxlen = KMOD_PATH_LEN, 455 .mode = 0644, 456 .proc_handler = &proc_dostring, 457 .strategy = &sysctl_string, 458 }, 459 #endif 460 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET) 461 { 462 .ctl_name = KERN_HOTPLUG, 463 .procname = "hotplug", 464 .data = &uevent_helper, 465 .maxlen = UEVENT_HELPER_PATH_LEN, 466 .mode = 0644, 467 .proc_handler = &proc_dostring, 468 .strategy = &sysctl_string, 469 }, 470 #endif 471 #ifdef CONFIG_CHR_DEV_SG 472 { 473 .ctl_name = KERN_SG_BIG_BUFF, 474 .procname = "sg-big-buff", 475 .data = &sg_big_buff, 476 .maxlen = sizeof (int), 477 .mode = 0444, 478 .proc_handler = &proc_dointvec, 479 }, 480 #endif 481 #ifdef CONFIG_BSD_PROCESS_ACCT 482 { 483 .ctl_name = KERN_ACCT, 484 .procname = "acct", 485 .data = &acct_parm, 486 .maxlen = 3*sizeof(int), 487 .mode = 0644, 488 .proc_handler = &proc_dointvec, 489 }, 490 #endif 491 #ifdef CONFIG_MAGIC_SYSRQ 492 { 493 .ctl_name = KERN_SYSRQ, 494 .procname = "sysrq", 495 .data = &__sysrq_enabled, 496 .maxlen = sizeof (int), 497 .mode = 0644, 498 .proc_handler = &proc_dointvec, 499 }, 500 #endif 501 #ifdef CONFIG_PROC_SYSCTL 502 { 503 .ctl_name = KERN_CADPID, 504 .procname = "cad_pid", 505 .data = NULL, 506 .maxlen = sizeof (int), 507 .mode = 0600, 508 .proc_handler = &proc_do_cad_pid, 509 }, 510 #endif 511 { 512 .ctl_name = KERN_MAX_THREADS, 513 .procname = "threads-max", 514 .data = &max_threads, 515 .maxlen = sizeof(int), 516 .mode = 0644, 517 .proc_handler = &proc_dointvec, 518 }, 519 { 520 .ctl_name = KERN_RANDOM, 521 .procname = "random", 522 .mode = 0555, 523 .child = random_table, 524 }, 525 #ifdef CONFIG_UNIX98_PTYS 526 { 527 .ctl_name = KERN_PTY, 528 .procname = "pty", 529 .mode = 0555, 530 .child = pty_table, 531 }, 532 #endif 533 { 534 .ctl_name = KERN_OVERFLOWUID, 535 .procname = "overflowuid", 536 .data = &overflowuid, 537 .maxlen = sizeof(int), 538 .mode = 0644, 539 .proc_handler = &proc_dointvec_minmax, 540 .strategy = &sysctl_intvec, 541 .extra1 = &minolduid, 542 .extra2 = &maxolduid, 543 }, 544 { 545 .ctl_name = KERN_OVERFLOWGID, 546 .procname = "overflowgid", 547 .data = &overflowgid, 548 .maxlen = sizeof(int), 549 .mode = 0644, 550 .proc_handler = &proc_dointvec_minmax, 551 .strategy = &sysctl_intvec, 552 .extra1 = &minolduid, 553 .extra2 = &maxolduid, 554 }, 555 #ifdef CONFIG_S390 556 #ifdef CONFIG_MATHEMU 557 { 558 .ctl_name = KERN_IEEE_EMULATION_WARNINGS, 559 .procname = "ieee_emulation_warnings", 560 .data = &sysctl_ieee_emulation_warnings, 561 .maxlen = sizeof(int), 562 .mode = 0644, 563 .proc_handler = &proc_dointvec, 564 }, 565 #endif 566 #ifdef CONFIG_NO_IDLE_HZ 567 { 568 .ctl_name = KERN_HZ_TIMER, 569 .procname = "hz_timer", 570 .data = &sysctl_hz_timer, 571 .maxlen = sizeof(int), 572 .mode = 0644, 573 .proc_handler = &proc_dointvec, 574 }, 575 #endif 576 { 577 .ctl_name = KERN_S390_USER_DEBUG_LOGGING, 578 .procname = "userprocess_debug", 579 .data = &sysctl_userprocess_debug, 580 .maxlen = sizeof(int), 581 .mode = 0644, 582 .proc_handler = &proc_dointvec, 583 }, 584 #endif 585 { 586 .ctl_name = KERN_PIDMAX, 587 .procname = "pid_max", 588 .data = &pid_max, 589 .maxlen = sizeof (int), 590 .mode = 0644, 591 .proc_handler = &proc_dointvec_minmax, 592 .strategy = sysctl_intvec, 593 .extra1 = &pid_max_min, 594 .extra2 = &pid_max_max, 595 }, 596 { 597 .ctl_name = KERN_PANIC_ON_OOPS, 598 .procname = "panic_on_oops", 599 .data = &panic_on_oops, 600 .maxlen = sizeof(int), 601 .mode = 0644, 602 .proc_handler = &proc_dointvec, 603 }, 604 { 605 .ctl_name = KERN_PRINTK_RATELIMIT, 606 .procname = "printk_ratelimit", 607 .data = &printk_ratelimit_jiffies, 608 .maxlen = sizeof(int), 609 .mode = 0644, 610 .proc_handler = &proc_dointvec_jiffies, 611 .strategy = &sysctl_jiffies, 612 }, 613 { 614 .ctl_name = KERN_PRINTK_RATELIMIT_BURST, 615 .procname = "printk_ratelimit_burst", 616 .data = &printk_ratelimit_burst, 617 .maxlen = sizeof(int), 618 .mode = 0644, 619 .proc_handler = &proc_dointvec, 620 }, 621 { 622 .ctl_name = KERN_NGROUPS_MAX, 623 .procname = "ngroups_max", 624 .data = &ngroups_max, 625 .maxlen = sizeof (int), 626 .mode = 0444, 627 .proc_handler = &proc_dointvec, 628 }, 629 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) 630 { 631 .ctl_name = KERN_UNKNOWN_NMI_PANIC, 632 .procname = "unknown_nmi_panic", 633 .data = &unknown_nmi_panic, 634 .maxlen = sizeof (int), 635 .mode = 0644, 636 .proc_handler = &proc_dointvec, 637 }, 638 { 639 .ctl_name = KERN_NMI_WATCHDOG, 640 .procname = "nmi_watchdog", 641 .data = &nmi_watchdog_enabled, 642 .maxlen = sizeof (int), 643 .mode = 0644, 644 .proc_handler = &proc_nmi_enabled, 645 }, 646 #endif 647 #if defined(CONFIG_X86) 648 { 649 .ctl_name = KERN_PANIC_ON_NMI, 650 .procname = "panic_on_unrecovered_nmi", 651 .data = &panic_on_unrecovered_nmi, 652 .maxlen = sizeof(int), 653 .mode = 0644, 654 .proc_handler = &proc_dointvec, 655 }, 656 { 657 .ctl_name = KERN_BOOTLOADER_TYPE, 658 .procname = "bootloader_type", 659 .data = &bootloader_type, 660 .maxlen = sizeof (int), 661 .mode = 0444, 662 .proc_handler = &proc_dointvec, 663 }, 664 { 665 .ctl_name = CTL_UNNUMBERED, 666 .procname = "kstack_depth_to_print", 667 .data = &kstack_depth_to_print, 668 .maxlen = sizeof(int), 669 .mode = 0644, 670 .proc_handler = &proc_dointvec, 671 }, 672 #endif 673 #if defined(CONFIG_MMU) 674 { 675 .ctl_name = KERN_RANDOMIZE, 676 .procname = "randomize_va_space", 677 .data = &randomize_va_space, 678 .maxlen = sizeof(int), 679 .mode = 0644, 680 .proc_handler = &proc_dointvec, 681 }, 682 #endif 683 #if defined(CONFIG_S390) && defined(CONFIG_SMP) 684 { 685 .ctl_name = KERN_SPIN_RETRY, 686 .procname = "spin_retry", 687 .data = &spin_retry, 688 .maxlen = sizeof (int), 689 .mode = 0644, 690 .proc_handler = &proc_dointvec, 691 }, 692 #endif 693 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86) 694 { 695 .ctl_name = KERN_ACPI_VIDEO_FLAGS, 696 .procname = "acpi_video_flags", 697 .data = &acpi_realmode_flags, 698 .maxlen = sizeof (unsigned long), 699 .mode = 0644, 700 .proc_handler = &proc_doulongvec_minmax, 701 }, 702 #endif 703 #ifdef CONFIG_IA64 704 { 705 .ctl_name = KERN_IA64_UNALIGNED, 706 .procname = "ignore-unaligned-usertrap", 707 .data = &no_unaligned_warning, 708 .maxlen = sizeof (int), 709 .mode = 0644, 710 .proc_handler = &proc_dointvec, 711 }, 712 #endif 713 #ifdef CONFIG_COMPAT 714 { 715 .ctl_name = KERN_COMPAT_LOG, 716 .procname = "compat-log", 717 .data = &compat_log, 718 .maxlen = sizeof (int), 719 .mode = 0644, 720 .proc_handler = &proc_dointvec, 721 }, 722 #endif 723 #ifdef CONFIG_RT_MUTEXES 724 { 725 .ctl_name = KERN_MAX_LOCK_DEPTH, 726 .procname = "max_lock_depth", 727 .data = &max_lock_depth, 728 .maxlen = sizeof(int), 729 .mode = 0644, 730 .proc_handler = &proc_dointvec, 731 }, 732 #endif 733 #ifdef CONFIG_PROC_FS 734 { 735 .ctl_name = CTL_UNNUMBERED, 736 .procname = "maps_protect", 737 .data = &maps_protect, 738 .maxlen = sizeof(int), 739 .mode = 0644, 740 .proc_handler = &proc_dointvec, 741 }, 742 #endif 743 { 744 .ctl_name = CTL_UNNUMBERED, 745 .procname = "poweroff_cmd", 746 .data = &poweroff_cmd, 747 .maxlen = POWEROFF_CMD_PATH_LEN, 748 .mode = 0644, 749 .proc_handler = &proc_dostring, 750 .strategy = &sysctl_string, 751 }, 752 /* 753 * NOTE: do not add new entries to this table unless you have read 754 * Documentation/sysctl/ctl_unnumbered.txt 755 */ 756 { .ctl_name = 0 } 757 }; 758 759 /* Constants for minimum and maximum testing in vm_table. 760 We use these as one-element integer vectors. */ 761 static int zero; 762 static int two = 2; 763 static int one_hundred = 100; 764 765 766 static ctl_table vm_table[] = { 767 { 768 .ctl_name = VM_OVERCOMMIT_MEMORY, 769 .procname = "overcommit_memory", 770 .data = &sysctl_overcommit_memory, 771 .maxlen = sizeof(sysctl_overcommit_memory), 772 .mode = 0644, 773 .proc_handler = &proc_dointvec, 774 }, 775 { 776 .ctl_name = VM_PANIC_ON_OOM, 777 .procname = "panic_on_oom", 778 .data = &sysctl_panic_on_oom, 779 .maxlen = sizeof(sysctl_panic_on_oom), 780 .mode = 0644, 781 .proc_handler = &proc_dointvec, 782 }, 783 { 784 .ctl_name = VM_OVERCOMMIT_RATIO, 785 .procname = "overcommit_ratio", 786 .data = &sysctl_overcommit_ratio, 787 .maxlen = sizeof(sysctl_overcommit_ratio), 788 .mode = 0644, 789 .proc_handler = &proc_dointvec, 790 }, 791 { 792 .ctl_name = VM_PAGE_CLUSTER, 793 .procname = "page-cluster", 794 .data = &page_cluster, 795 .maxlen = sizeof(int), 796 .mode = 0644, 797 .proc_handler = &proc_dointvec, 798 }, 799 { 800 .ctl_name = VM_DIRTY_BACKGROUND, 801 .procname = "dirty_background_ratio", 802 .data = &dirty_background_ratio, 803 .maxlen = sizeof(dirty_background_ratio), 804 .mode = 0644, 805 .proc_handler = &proc_dointvec_minmax, 806 .strategy = &sysctl_intvec, 807 .extra1 = &zero, 808 .extra2 = &one_hundred, 809 }, 810 { 811 .ctl_name = VM_DIRTY_RATIO, 812 .procname = "dirty_ratio", 813 .data = &vm_dirty_ratio, 814 .maxlen = sizeof(vm_dirty_ratio), 815 .mode = 0644, 816 .proc_handler = &proc_dointvec_minmax, 817 .strategy = &sysctl_intvec, 818 .extra1 = &zero, 819 .extra2 = &one_hundred, 820 }, 821 { 822 .ctl_name = VM_DIRTY_WB_CS, 823 .procname = "dirty_writeback_centisecs", 824 .data = &dirty_writeback_interval, 825 .maxlen = sizeof(dirty_writeback_interval), 826 .mode = 0644, 827 .proc_handler = &dirty_writeback_centisecs_handler, 828 }, 829 { 830 .ctl_name = VM_DIRTY_EXPIRE_CS, 831 .procname = "dirty_expire_centisecs", 832 .data = &dirty_expire_interval, 833 .maxlen = sizeof(dirty_expire_interval), 834 .mode = 0644, 835 .proc_handler = &proc_dointvec_userhz_jiffies, 836 }, 837 { 838 .ctl_name = VM_NR_PDFLUSH_THREADS, 839 .procname = "nr_pdflush_threads", 840 .data = &nr_pdflush_threads, 841 .maxlen = sizeof nr_pdflush_threads, 842 .mode = 0444 /* read-only*/, 843 .proc_handler = &proc_dointvec, 844 }, 845 { 846 .ctl_name = VM_SWAPPINESS, 847 .procname = "swappiness", 848 .data = &vm_swappiness, 849 .maxlen = sizeof(vm_swappiness), 850 .mode = 0644, 851 .proc_handler = &proc_dointvec_minmax, 852 .strategy = &sysctl_intvec, 853 .extra1 = &zero, 854 .extra2 = &one_hundred, 855 }, 856 #ifdef CONFIG_HUGETLB_PAGE 857 { 858 .ctl_name = VM_HUGETLB_PAGES, 859 .procname = "nr_hugepages", 860 .data = &max_huge_pages, 861 .maxlen = sizeof(unsigned long), 862 .mode = 0644, 863 .proc_handler = &hugetlb_sysctl_handler, 864 .extra1 = (void *)&hugetlb_zero, 865 .extra2 = (void *)&hugetlb_infinity, 866 }, 867 { 868 .ctl_name = VM_HUGETLB_GROUP, 869 .procname = "hugetlb_shm_group", 870 .data = &sysctl_hugetlb_shm_group, 871 .maxlen = sizeof(gid_t), 872 .mode = 0644, 873 .proc_handler = &proc_dointvec, 874 }, 875 { 876 .ctl_name = CTL_UNNUMBERED, 877 .procname = "hugepages_treat_as_movable", 878 .data = &hugepages_treat_as_movable, 879 .maxlen = sizeof(int), 880 .mode = 0644, 881 .proc_handler = &hugetlb_treat_movable_handler, 882 }, 883 { 884 .ctl_name = CTL_UNNUMBERED, 885 .procname = "hugetlb_dynamic_pool", 886 .data = &hugetlb_dynamic_pool, 887 .maxlen = sizeof(hugetlb_dynamic_pool), 888 .mode = 0644, 889 .proc_handler = &proc_dointvec, 890 }, 891 #endif 892 { 893 .ctl_name = VM_LOWMEM_RESERVE_RATIO, 894 .procname = "lowmem_reserve_ratio", 895 .data = &sysctl_lowmem_reserve_ratio, 896 .maxlen = sizeof(sysctl_lowmem_reserve_ratio), 897 .mode = 0644, 898 .proc_handler = &lowmem_reserve_ratio_sysctl_handler, 899 .strategy = &sysctl_intvec, 900 }, 901 { 902 .ctl_name = VM_DROP_PAGECACHE, 903 .procname = "drop_caches", 904 .data = &sysctl_drop_caches, 905 .maxlen = sizeof(int), 906 .mode = 0644, 907 .proc_handler = drop_caches_sysctl_handler, 908 .strategy = &sysctl_intvec, 909 }, 910 { 911 .ctl_name = VM_MIN_FREE_KBYTES, 912 .procname = "min_free_kbytes", 913 .data = &min_free_kbytes, 914 .maxlen = sizeof(min_free_kbytes), 915 .mode = 0644, 916 .proc_handler = &min_free_kbytes_sysctl_handler, 917 .strategy = &sysctl_intvec, 918 .extra1 = &zero, 919 }, 920 { 921 .ctl_name = VM_PERCPU_PAGELIST_FRACTION, 922 .procname = "percpu_pagelist_fraction", 923 .data = &percpu_pagelist_fraction, 924 .maxlen = sizeof(percpu_pagelist_fraction), 925 .mode = 0644, 926 .proc_handler = &percpu_pagelist_fraction_sysctl_handler, 927 .strategy = &sysctl_intvec, 928 .extra1 = &min_percpu_pagelist_fract, 929 }, 930 #ifdef CONFIG_MMU 931 { 932 .ctl_name = VM_MAX_MAP_COUNT, 933 .procname = "max_map_count", 934 .data = &sysctl_max_map_count, 935 .maxlen = sizeof(sysctl_max_map_count), 936 .mode = 0644, 937 .proc_handler = &proc_dointvec 938 }, 939 #endif 940 { 941 .ctl_name = VM_LAPTOP_MODE, 942 .procname = "laptop_mode", 943 .data = &laptop_mode, 944 .maxlen = sizeof(laptop_mode), 945 .mode = 0644, 946 .proc_handler = &proc_dointvec_jiffies, 947 .strategy = &sysctl_jiffies, 948 }, 949 { 950 .ctl_name = VM_BLOCK_DUMP, 951 .procname = "block_dump", 952 .data = &block_dump, 953 .maxlen = sizeof(block_dump), 954 .mode = 0644, 955 .proc_handler = &proc_dointvec, 956 .strategy = &sysctl_intvec, 957 .extra1 = &zero, 958 }, 959 { 960 .ctl_name = VM_VFS_CACHE_PRESSURE, 961 .procname = "vfs_cache_pressure", 962 .data = &sysctl_vfs_cache_pressure, 963 .maxlen = sizeof(sysctl_vfs_cache_pressure), 964 .mode = 0644, 965 .proc_handler = &proc_dointvec, 966 .strategy = &sysctl_intvec, 967 .extra1 = &zero, 968 }, 969 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 970 { 971 .ctl_name = VM_LEGACY_VA_LAYOUT, 972 .procname = "legacy_va_layout", 973 .data = &sysctl_legacy_va_layout, 974 .maxlen = sizeof(sysctl_legacy_va_layout), 975 .mode = 0644, 976 .proc_handler = &proc_dointvec, 977 .strategy = &sysctl_intvec, 978 .extra1 = &zero, 979 }, 980 #endif 981 #ifdef CONFIG_NUMA 982 { 983 .ctl_name = VM_ZONE_RECLAIM_MODE, 984 .procname = "zone_reclaim_mode", 985 .data = &zone_reclaim_mode, 986 .maxlen = sizeof(zone_reclaim_mode), 987 .mode = 0644, 988 .proc_handler = &proc_dointvec, 989 .strategy = &sysctl_intvec, 990 .extra1 = &zero, 991 }, 992 { 993 .ctl_name = VM_MIN_UNMAPPED, 994 .procname = "min_unmapped_ratio", 995 .data = &sysctl_min_unmapped_ratio, 996 .maxlen = sizeof(sysctl_min_unmapped_ratio), 997 .mode = 0644, 998 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler, 999 .strategy = &sysctl_intvec, 1000 .extra1 = &zero, 1001 .extra2 = &one_hundred, 1002 }, 1003 { 1004 .ctl_name = VM_MIN_SLAB, 1005 .procname = "min_slab_ratio", 1006 .data = &sysctl_min_slab_ratio, 1007 .maxlen = sizeof(sysctl_min_slab_ratio), 1008 .mode = 0644, 1009 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler, 1010 .strategy = &sysctl_intvec, 1011 .extra1 = &zero, 1012 .extra2 = &one_hundred, 1013 }, 1014 #endif 1015 #ifdef CONFIG_SMP 1016 { 1017 .ctl_name = CTL_UNNUMBERED, 1018 .procname = "stat_interval", 1019 .data = &sysctl_stat_interval, 1020 .maxlen = sizeof(sysctl_stat_interval), 1021 .mode = 0644, 1022 .proc_handler = &proc_dointvec_jiffies, 1023 .strategy = &sysctl_jiffies, 1024 }, 1025 #endif 1026 #ifdef CONFIG_SECURITY 1027 { 1028 .ctl_name = CTL_UNNUMBERED, 1029 .procname = "mmap_min_addr", 1030 .data = &mmap_min_addr, 1031 .maxlen = sizeof(unsigned long), 1032 .mode = 0644, 1033 .proc_handler = &proc_doulongvec_minmax, 1034 }, 1035 #endif 1036 #ifdef CONFIG_NUMA 1037 { 1038 .ctl_name = CTL_UNNUMBERED, 1039 .procname = "numa_zonelist_order", 1040 .data = &numa_zonelist_order, 1041 .maxlen = NUMA_ZONELIST_ORDER_LEN, 1042 .mode = 0644, 1043 .proc_handler = &numa_zonelist_order_handler, 1044 .strategy = &sysctl_string, 1045 }, 1046 #endif 1047 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \ 1048 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL)) 1049 { 1050 .ctl_name = VM_VDSO_ENABLED, 1051 .procname = "vdso_enabled", 1052 .data = &vdso_enabled, 1053 .maxlen = sizeof(vdso_enabled), 1054 .mode = 0644, 1055 .proc_handler = &proc_dointvec, 1056 .strategy = &sysctl_intvec, 1057 .extra1 = &zero, 1058 }, 1059 #endif 1060 /* 1061 * NOTE: do not add new entries to this table unless you have read 1062 * Documentation/sysctl/ctl_unnumbered.txt 1063 */ 1064 { .ctl_name = 0 } 1065 }; 1066 1067 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) 1068 static ctl_table binfmt_misc_table[] = { 1069 { .ctl_name = 0 } 1070 }; 1071 #endif 1072 1073 static ctl_table fs_table[] = { 1074 { 1075 .ctl_name = FS_NRINODE, 1076 .procname = "inode-nr", 1077 .data = &inodes_stat, 1078 .maxlen = 2*sizeof(int), 1079 .mode = 0444, 1080 .proc_handler = &proc_dointvec, 1081 }, 1082 { 1083 .ctl_name = FS_STATINODE, 1084 .procname = "inode-state", 1085 .data = &inodes_stat, 1086 .maxlen = 7*sizeof(int), 1087 .mode = 0444, 1088 .proc_handler = &proc_dointvec, 1089 }, 1090 { 1091 .ctl_name = FS_NRFILE, 1092 .procname = "file-nr", 1093 .data = &files_stat, 1094 .maxlen = 3*sizeof(int), 1095 .mode = 0444, 1096 .proc_handler = &proc_nr_files, 1097 }, 1098 { 1099 .ctl_name = FS_MAXFILE, 1100 .procname = "file-max", 1101 .data = &files_stat.max_files, 1102 .maxlen = sizeof(int), 1103 .mode = 0644, 1104 .proc_handler = &proc_dointvec, 1105 }, 1106 { 1107 .ctl_name = FS_DENTRY, 1108 .procname = "dentry-state", 1109 .data = &dentry_stat, 1110 .maxlen = 6*sizeof(int), 1111 .mode = 0444, 1112 .proc_handler = &proc_dointvec, 1113 }, 1114 { 1115 .ctl_name = FS_OVERFLOWUID, 1116 .procname = "overflowuid", 1117 .data = &fs_overflowuid, 1118 .maxlen = sizeof(int), 1119 .mode = 0644, 1120 .proc_handler = &proc_dointvec_minmax, 1121 .strategy = &sysctl_intvec, 1122 .extra1 = &minolduid, 1123 .extra2 = &maxolduid, 1124 }, 1125 { 1126 .ctl_name = FS_OVERFLOWGID, 1127 .procname = "overflowgid", 1128 .data = &fs_overflowgid, 1129 .maxlen = sizeof(int), 1130 .mode = 0644, 1131 .proc_handler = &proc_dointvec_minmax, 1132 .strategy = &sysctl_intvec, 1133 .extra1 = &minolduid, 1134 .extra2 = &maxolduid, 1135 }, 1136 { 1137 .ctl_name = FS_LEASES, 1138 .procname = "leases-enable", 1139 .data = &leases_enable, 1140 .maxlen = sizeof(int), 1141 .mode = 0644, 1142 .proc_handler = &proc_dointvec, 1143 }, 1144 #ifdef CONFIG_DNOTIFY 1145 { 1146 .ctl_name = FS_DIR_NOTIFY, 1147 .procname = "dir-notify-enable", 1148 .data = &dir_notify_enable, 1149 .maxlen = sizeof(int), 1150 .mode = 0644, 1151 .proc_handler = &proc_dointvec, 1152 }, 1153 #endif 1154 #ifdef CONFIG_MMU 1155 { 1156 .ctl_name = FS_LEASE_TIME, 1157 .procname = "lease-break-time", 1158 .data = &lease_break_time, 1159 .maxlen = sizeof(int), 1160 .mode = 0644, 1161 .proc_handler = &proc_dointvec_minmax, 1162 .strategy = &sysctl_intvec, 1163 .extra1 = &zero, 1164 .extra2 = &two, 1165 }, 1166 { 1167 .ctl_name = FS_AIO_NR, 1168 .procname = "aio-nr", 1169 .data = &aio_nr, 1170 .maxlen = sizeof(aio_nr), 1171 .mode = 0444, 1172 .proc_handler = &proc_doulongvec_minmax, 1173 }, 1174 { 1175 .ctl_name = FS_AIO_MAX_NR, 1176 .procname = "aio-max-nr", 1177 .data = &aio_max_nr, 1178 .maxlen = sizeof(aio_max_nr), 1179 .mode = 0644, 1180 .proc_handler = &proc_doulongvec_minmax, 1181 }, 1182 #ifdef CONFIG_INOTIFY_USER 1183 { 1184 .ctl_name = FS_INOTIFY, 1185 .procname = "inotify", 1186 .mode = 0555, 1187 .child = inotify_table, 1188 }, 1189 #endif 1190 #endif 1191 { 1192 .ctl_name = KERN_SETUID_DUMPABLE, 1193 .procname = "suid_dumpable", 1194 .data = &suid_dumpable, 1195 .maxlen = sizeof(int), 1196 .mode = 0644, 1197 .proc_handler = &proc_dointvec, 1198 }, 1199 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) 1200 { 1201 .ctl_name = CTL_UNNUMBERED, 1202 .procname = "binfmt_misc", 1203 .mode = 0555, 1204 .child = binfmt_misc_table, 1205 }, 1206 #endif 1207 /* 1208 * NOTE: do not add new entries to this table unless you have read 1209 * Documentation/sysctl/ctl_unnumbered.txt 1210 */ 1211 { .ctl_name = 0 } 1212 }; 1213 1214 static ctl_table debug_table[] = { 1215 #if defined(CONFIG_X86) || defined(CONFIG_PPC) 1216 { 1217 .ctl_name = CTL_UNNUMBERED, 1218 .procname = "exception-trace", 1219 .data = &show_unhandled_signals, 1220 .maxlen = sizeof(int), 1221 .mode = 0644, 1222 .proc_handler = proc_dointvec 1223 }, 1224 #endif 1225 { .ctl_name = 0 } 1226 }; 1227 1228 static ctl_table dev_table[] = { 1229 { .ctl_name = 0 } 1230 }; 1231 1232 static DEFINE_SPINLOCK(sysctl_lock); 1233 1234 /* called under sysctl_lock */ 1235 static int use_table(struct ctl_table_header *p) 1236 { 1237 if (unlikely(p->unregistering)) 1238 return 0; 1239 p->used++; 1240 return 1; 1241 } 1242 1243 /* called under sysctl_lock */ 1244 static void unuse_table(struct ctl_table_header *p) 1245 { 1246 if (!--p->used) 1247 if (unlikely(p->unregistering)) 1248 complete(p->unregistering); 1249 } 1250 1251 /* called under sysctl_lock, will reacquire if has to wait */ 1252 static void start_unregistering(struct ctl_table_header *p) 1253 { 1254 /* 1255 * if p->used is 0, nobody will ever touch that entry again; 1256 * we'll eliminate all paths to it before dropping sysctl_lock 1257 */ 1258 if (unlikely(p->used)) { 1259 struct completion wait; 1260 init_completion(&wait); 1261 p->unregistering = &wait; 1262 spin_unlock(&sysctl_lock); 1263 wait_for_completion(&wait); 1264 spin_lock(&sysctl_lock); 1265 } 1266 /* 1267 * do not remove from the list until nobody holds it; walking the 1268 * list in do_sysctl() relies on that. 1269 */ 1270 list_del_init(&p->ctl_entry); 1271 } 1272 1273 void sysctl_head_finish(struct ctl_table_header *head) 1274 { 1275 if (!head) 1276 return; 1277 spin_lock(&sysctl_lock); 1278 unuse_table(head); 1279 spin_unlock(&sysctl_lock); 1280 } 1281 1282 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev) 1283 { 1284 struct ctl_table_header *head; 1285 struct list_head *tmp; 1286 spin_lock(&sysctl_lock); 1287 if (prev) { 1288 tmp = &prev->ctl_entry; 1289 unuse_table(prev); 1290 goto next; 1291 } 1292 tmp = &root_table_header.ctl_entry; 1293 for (;;) { 1294 head = list_entry(tmp, struct ctl_table_header, ctl_entry); 1295 1296 if (!use_table(head)) 1297 goto next; 1298 spin_unlock(&sysctl_lock); 1299 return head; 1300 next: 1301 tmp = tmp->next; 1302 if (tmp == &root_table_header.ctl_entry) 1303 break; 1304 } 1305 spin_unlock(&sysctl_lock); 1306 return NULL; 1307 } 1308 1309 #ifdef CONFIG_SYSCTL_SYSCALL 1310 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, 1311 void __user *newval, size_t newlen) 1312 { 1313 struct ctl_table_header *head; 1314 int error = -ENOTDIR; 1315 1316 if (nlen <= 0 || nlen >= CTL_MAXNAME) 1317 return -ENOTDIR; 1318 if (oldval) { 1319 int old_len; 1320 if (!oldlenp || get_user(old_len, oldlenp)) 1321 return -EFAULT; 1322 } 1323 1324 for (head = sysctl_head_next(NULL); head; 1325 head = sysctl_head_next(head)) { 1326 error = parse_table(name, nlen, oldval, oldlenp, 1327 newval, newlen, head->ctl_table); 1328 if (error != -ENOTDIR) { 1329 sysctl_head_finish(head); 1330 break; 1331 } 1332 } 1333 return error; 1334 } 1335 1336 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 1337 { 1338 struct __sysctl_args tmp; 1339 int error; 1340 1341 if (copy_from_user(&tmp, args, sizeof(tmp))) 1342 return -EFAULT; 1343 1344 lock_kernel(); 1345 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp, 1346 tmp.newval, tmp.newlen); 1347 unlock_kernel(); 1348 return error; 1349 } 1350 #endif /* CONFIG_SYSCTL_SYSCALL */ 1351 1352 /* 1353 * sysctl_perm does NOT grant the superuser all rights automatically, because 1354 * some sysctl variables are readonly even to root. 1355 */ 1356 1357 static int test_perm(int mode, int op) 1358 { 1359 if (!current->euid) 1360 mode >>= 6; 1361 else if (in_egroup_p(0)) 1362 mode >>= 3; 1363 if ((mode & op & 0007) == op) 1364 return 0; 1365 return -EACCES; 1366 } 1367 1368 int sysctl_perm(ctl_table *table, int op) 1369 { 1370 int error; 1371 error = security_sysctl(table, op); 1372 if (error) 1373 return error; 1374 return test_perm(table->mode, op); 1375 } 1376 1377 #ifdef CONFIG_SYSCTL_SYSCALL 1378 static int parse_table(int __user *name, int nlen, 1379 void __user *oldval, size_t __user *oldlenp, 1380 void __user *newval, size_t newlen, 1381 ctl_table *table) 1382 { 1383 int n; 1384 repeat: 1385 if (!nlen) 1386 return -ENOTDIR; 1387 if (get_user(n, name)) 1388 return -EFAULT; 1389 for ( ; table->ctl_name || table->procname; table++) { 1390 if (!table->ctl_name) 1391 continue; 1392 if (n == table->ctl_name) { 1393 int error; 1394 if (table->child) { 1395 if (sysctl_perm(table, 001)) 1396 return -EPERM; 1397 name++; 1398 nlen--; 1399 table = table->child; 1400 goto repeat; 1401 } 1402 error = do_sysctl_strategy(table, name, nlen, 1403 oldval, oldlenp, 1404 newval, newlen); 1405 return error; 1406 } 1407 } 1408 return -ENOTDIR; 1409 } 1410 1411 /* Perform the actual read/write of a sysctl table entry. */ 1412 int do_sysctl_strategy (ctl_table *table, 1413 int __user *name, int nlen, 1414 void __user *oldval, size_t __user *oldlenp, 1415 void __user *newval, size_t newlen) 1416 { 1417 int op = 0, rc; 1418 size_t len; 1419 1420 if (oldval) 1421 op |= 004; 1422 if (newval) 1423 op |= 002; 1424 if (sysctl_perm(table, op)) 1425 return -EPERM; 1426 1427 if (table->strategy) { 1428 rc = table->strategy(table, name, nlen, oldval, oldlenp, 1429 newval, newlen); 1430 if (rc < 0) 1431 return rc; 1432 if (rc > 0) 1433 return 0; 1434 } 1435 1436 /* If there is no strategy routine, or if the strategy returns 1437 * zero, proceed with automatic r/w */ 1438 if (table->data && table->maxlen) { 1439 if (oldval && oldlenp) { 1440 if (get_user(len, oldlenp)) 1441 return -EFAULT; 1442 if (len) { 1443 if (len > table->maxlen) 1444 len = table->maxlen; 1445 if(copy_to_user(oldval, table->data, len)) 1446 return -EFAULT; 1447 if(put_user(len, oldlenp)) 1448 return -EFAULT; 1449 } 1450 } 1451 if (newval && newlen) { 1452 len = newlen; 1453 if (len > table->maxlen) 1454 len = table->maxlen; 1455 if(copy_from_user(table->data, newval, len)) 1456 return -EFAULT; 1457 } 1458 } 1459 return 0; 1460 } 1461 #endif /* CONFIG_SYSCTL_SYSCALL */ 1462 1463 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table) 1464 { 1465 for (; table->ctl_name || table->procname; table++) { 1466 table->parent = parent; 1467 if (table->child) 1468 sysctl_set_parent(table, table->child); 1469 } 1470 } 1471 1472 static __init int sysctl_init(void) 1473 { 1474 sysctl_set_parent(NULL, root_table); 1475 return 0; 1476 } 1477 1478 core_initcall(sysctl_init); 1479 1480 /** 1481 * register_sysctl_table - register a sysctl hierarchy 1482 * @table: the top-level table structure 1483 * 1484 * Register a sysctl table hierarchy. @table should be a filled in ctl_table 1485 * array. An entry with a ctl_name of 0 terminates the table. 1486 * 1487 * The members of the &ctl_table structure are used as follows: 1488 * 1489 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number 1490 * must be unique within that level of sysctl 1491 * 1492 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not 1493 * enter a sysctl file 1494 * 1495 * data - a pointer to data for use by proc_handler 1496 * 1497 * maxlen - the maximum size in bytes of the data 1498 * 1499 * mode - the file permissions for the /proc/sys file, and for sysctl(2) 1500 * 1501 * child - a pointer to the child sysctl table if this entry is a directory, or 1502 * %NULL. 1503 * 1504 * proc_handler - the text handler routine (described below) 1505 * 1506 * strategy - the strategy routine (described below) 1507 * 1508 * de - for internal use by the sysctl routines 1509 * 1510 * extra1, extra2 - extra pointers usable by the proc handler routines 1511 * 1512 * Leaf nodes in the sysctl tree will be represented by a single file 1513 * under /proc; non-leaf nodes will be represented by directories. 1514 * 1515 * sysctl(2) can automatically manage read and write requests through 1516 * the sysctl table. The data and maxlen fields of the ctl_table 1517 * struct enable minimal validation of the values being written to be 1518 * performed, and the mode field allows minimal authentication. 1519 * 1520 * More sophisticated management can be enabled by the provision of a 1521 * strategy routine with the table entry. This will be called before 1522 * any automatic read or write of the data is performed. 1523 * 1524 * The strategy routine may return 1525 * 1526 * < 0 - Error occurred (error is passed to user process) 1527 * 1528 * 0 - OK - proceed with automatic read or write. 1529 * 1530 * > 0 - OK - read or write has been done by the strategy routine, so 1531 * return immediately. 1532 * 1533 * There must be a proc_handler routine for any terminal nodes 1534 * mirrored under /proc/sys (non-terminals are handled by a built-in 1535 * directory handler). Several default handlers are available to 1536 * cover common cases - 1537 * 1538 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(), 1539 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 1540 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax() 1541 * 1542 * It is the handler's job to read the input buffer from user memory 1543 * and process it. The handler should return 0 on success. 1544 * 1545 * This routine returns %NULL on a failure to register, and a pointer 1546 * to the table header on success. 1547 */ 1548 struct ctl_table_header *register_sysctl_table(ctl_table * table) 1549 { 1550 struct ctl_table_header *tmp; 1551 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL); 1552 if (!tmp) 1553 return NULL; 1554 tmp->ctl_table = table; 1555 INIT_LIST_HEAD(&tmp->ctl_entry); 1556 tmp->used = 0; 1557 tmp->unregistering = NULL; 1558 sysctl_set_parent(NULL, table); 1559 spin_lock(&sysctl_lock); 1560 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry); 1561 spin_unlock(&sysctl_lock); 1562 return tmp; 1563 } 1564 1565 /** 1566 * unregister_sysctl_table - unregister a sysctl table hierarchy 1567 * @header: the header returned from register_sysctl_table 1568 * 1569 * Unregisters the sysctl table and all children. proc entries may not 1570 * actually be removed until they are no longer used by anyone. 1571 */ 1572 void unregister_sysctl_table(struct ctl_table_header * header) 1573 { 1574 might_sleep(); 1575 spin_lock(&sysctl_lock); 1576 start_unregistering(header); 1577 spin_unlock(&sysctl_lock); 1578 kfree(header); 1579 } 1580 1581 #else /* !CONFIG_SYSCTL */ 1582 struct ctl_table_header *register_sysctl_table(ctl_table * table) 1583 { 1584 return NULL; 1585 } 1586 1587 void unregister_sysctl_table(struct ctl_table_header * table) 1588 { 1589 } 1590 1591 #endif /* CONFIG_SYSCTL */ 1592 1593 /* 1594 * /proc/sys support 1595 */ 1596 1597 #ifdef CONFIG_PROC_SYSCTL 1598 1599 static int _proc_do_string(void* data, int maxlen, int write, 1600 struct file *filp, void __user *buffer, 1601 size_t *lenp, loff_t *ppos) 1602 { 1603 size_t len; 1604 char __user *p; 1605 char c; 1606 1607 if (!data || !maxlen || !*lenp) { 1608 *lenp = 0; 1609 return 0; 1610 } 1611 1612 if (write) { 1613 len = 0; 1614 p = buffer; 1615 while (len < *lenp) { 1616 if (get_user(c, p++)) 1617 return -EFAULT; 1618 if (c == 0 || c == '\n') 1619 break; 1620 len++; 1621 } 1622 if (len >= maxlen) 1623 len = maxlen-1; 1624 if(copy_from_user(data, buffer, len)) 1625 return -EFAULT; 1626 ((char *) data)[len] = 0; 1627 *ppos += *lenp; 1628 } else { 1629 len = strlen(data); 1630 if (len > maxlen) 1631 len = maxlen; 1632 1633 if (*ppos > len) { 1634 *lenp = 0; 1635 return 0; 1636 } 1637 1638 data += *ppos; 1639 len -= *ppos; 1640 1641 if (len > *lenp) 1642 len = *lenp; 1643 if (len) 1644 if(copy_to_user(buffer, data, len)) 1645 return -EFAULT; 1646 if (len < *lenp) { 1647 if(put_user('\n', ((char __user *) buffer) + len)) 1648 return -EFAULT; 1649 len++; 1650 } 1651 *lenp = len; 1652 *ppos += len; 1653 } 1654 return 0; 1655 } 1656 1657 /** 1658 * proc_dostring - read a string sysctl 1659 * @table: the sysctl table 1660 * @write: %TRUE if this is a write to the sysctl file 1661 * @filp: the file structure 1662 * @buffer: the user buffer 1663 * @lenp: the size of the user buffer 1664 * @ppos: file position 1665 * 1666 * Reads/writes a string from/to the user buffer. If the kernel 1667 * buffer provided is not large enough to hold the string, the 1668 * string is truncated. The copied string is %NULL-terminated. 1669 * If the string is being read by the user process, it is copied 1670 * and a newline '\n' is added. It is truncated if the buffer is 1671 * not large enough. 1672 * 1673 * Returns 0 on success. 1674 */ 1675 int proc_dostring(ctl_table *table, int write, struct file *filp, 1676 void __user *buffer, size_t *lenp, loff_t *ppos) 1677 { 1678 return _proc_do_string(table->data, table->maxlen, write, filp, 1679 buffer, lenp, ppos); 1680 } 1681 1682 1683 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp, 1684 int *valp, 1685 int write, void *data) 1686 { 1687 if (write) { 1688 *valp = *negp ? -*lvalp : *lvalp; 1689 } else { 1690 int val = *valp; 1691 if (val < 0) { 1692 *negp = -1; 1693 *lvalp = (unsigned long)-val; 1694 } else { 1695 *negp = 0; 1696 *lvalp = (unsigned long)val; 1697 } 1698 } 1699 return 0; 1700 } 1701 1702 static int __do_proc_dointvec(void *tbl_data, ctl_table *table, 1703 int write, struct file *filp, void __user *buffer, 1704 size_t *lenp, loff_t *ppos, 1705 int (*conv)(int *negp, unsigned long *lvalp, int *valp, 1706 int write, void *data), 1707 void *data) 1708 { 1709 #define TMPBUFLEN 21 1710 int *i, vleft, first=1, neg, val; 1711 unsigned long lval; 1712 size_t left, len; 1713 1714 char buf[TMPBUFLEN], *p; 1715 char __user *s = buffer; 1716 1717 if (!tbl_data || !table->maxlen || !*lenp || 1718 (*ppos && !write)) { 1719 *lenp = 0; 1720 return 0; 1721 } 1722 1723 i = (int *) tbl_data; 1724 vleft = table->maxlen / sizeof(*i); 1725 left = *lenp; 1726 1727 if (!conv) 1728 conv = do_proc_dointvec_conv; 1729 1730 for (; left && vleft--; i++, first=0) { 1731 if (write) { 1732 while (left) { 1733 char c; 1734 if (get_user(c, s)) 1735 return -EFAULT; 1736 if (!isspace(c)) 1737 break; 1738 left--; 1739 s++; 1740 } 1741 if (!left) 1742 break; 1743 neg = 0; 1744 len = left; 1745 if (len > sizeof(buf) - 1) 1746 len = sizeof(buf) - 1; 1747 if (copy_from_user(buf, s, len)) 1748 return -EFAULT; 1749 buf[len] = 0; 1750 p = buf; 1751 if (*p == '-' && left > 1) { 1752 neg = 1; 1753 p++; 1754 } 1755 if (*p < '0' || *p > '9') 1756 break; 1757 1758 lval = simple_strtoul(p, &p, 0); 1759 1760 len = p-buf; 1761 if ((len < left) && *p && !isspace(*p)) 1762 break; 1763 if (neg) 1764 val = -val; 1765 s += len; 1766 left -= len; 1767 1768 if (conv(&neg, &lval, i, 1, data)) 1769 break; 1770 } else { 1771 p = buf; 1772 if (!first) 1773 *p++ = '\t'; 1774 1775 if (conv(&neg, &lval, i, 0, data)) 1776 break; 1777 1778 sprintf(p, "%s%lu", neg ? "-" : "", lval); 1779 len = strlen(buf); 1780 if (len > left) 1781 len = left; 1782 if(copy_to_user(s, buf, len)) 1783 return -EFAULT; 1784 left -= len; 1785 s += len; 1786 } 1787 } 1788 1789 if (!write && !first && left) { 1790 if(put_user('\n', s)) 1791 return -EFAULT; 1792 left--, s++; 1793 } 1794 if (write) { 1795 while (left) { 1796 char c; 1797 if (get_user(c, s++)) 1798 return -EFAULT; 1799 if (!isspace(c)) 1800 break; 1801 left--; 1802 } 1803 } 1804 if (write && first) 1805 return -EINVAL; 1806 *lenp -= left; 1807 *ppos += *lenp; 1808 return 0; 1809 #undef TMPBUFLEN 1810 } 1811 1812 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp, 1813 void __user *buffer, size_t *lenp, loff_t *ppos, 1814 int (*conv)(int *negp, unsigned long *lvalp, int *valp, 1815 int write, void *data), 1816 void *data) 1817 { 1818 return __do_proc_dointvec(table->data, table, write, filp, 1819 buffer, lenp, ppos, conv, data); 1820 } 1821 1822 /** 1823 * proc_dointvec - read a vector of integers 1824 * @table: the sysctl table 1825 * @write: %TRUE if this is a write to the sysctl file 1826 * @filp: the file structure 1827 * @buffer: the user buffer 1828 * @lenp: the size of the user buffer 1829 * @ppos: file position 1830 * 1831 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 1832 * values from/to the user buffer, treated as an ASCII string. 1833 * 1834 * Returns 0 on success. 1835 */ 1836 int proc_dointvec(ctl_table *table, int write, struct file *filp, 1837 void __user *buffer, size_t *lenp, loff_t *ppos) 1838 { 1839 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1840 NULL,NULL); 1841 } 1842 1843 #define OP_SET 0 1844 #define OP_AND 1 1845 #define OP_OR 2 1846 1847 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp, 1848 int *valp, 1849 int write, void *data) 1850 { 1851 int op = *(int *)data; 1852 if (write) { 1853 int val = *negp ? -*lvalp : *lvalp; 1854 switch(op) { 1855 case OP_SET: *valp = val; break; 1856 case OP_AND: *valp &= val; break; 1857 case OP_OR: *valp |= val; break; 1858 } 1859 } else { 1860 int val = *valp; 1861 if (val < 0) { 1862 *negp = -1; 1863 *lvalp = (unsigned long)-val; 1864 } else { 1865 *negp = 0; 1866 *lvalp = (unsigned long)val; 1867 } 1868 } 1869 return 0; 1870 } 1871 1872 /* 1873 * init may raise the set. 1874 */ 1875 1876 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 1877 void __user *buffer, size_t *lenp, loff_t *ppos) 1878 { 1879 int op; 1880 1881 if (write && !capable(CAP_SYS_MODULE)) { 1882 return -EPERM; 1883 } 1884 1885 op = is_init(current) ? OP_SET : OP_AND; 1886 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1887 do_proc_dointvec_bset_conv,&op); 1888 } 1889 1890 /* 1891 * Taint values can only be increased 1892 */ 1893 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp, 1894 void __user *buffer, size_t *lenp, loff_t *ppos) 1895 { 1896 int op; 1897 1898 if (write && !capable(CAP_SYS_ADMIN)) 1899 return -EPERM; 1900 1901 op = OP_OR; 1902 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1903 do_proc_dointvec_bset_conv,&op); 1904 } 1905 1906 struct do_proc_dointvec_minmax_conv_param { 1907 int *min; 1908 int *max; 1909 }; 1910 1911 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 1912 int *valp, 1913 int write, void *data) 1914 { 1915 struct do_proc_dointvec_minmax_conv_param *param = data; 1916 if (write) { 1917 int val = *negp ? -*lvalp : *lvalp; 1918 if ((param->min && *param->min > val) || 1919 (param->max && *param->max < val)) 1920 return -EINVAL; 1921 *valp = val; 1922 } else { 1923 int val = *valp; 1924 if (val < 0) { 1925 *negp = -1; 1926 *lvalp = (unsigned long)-val; 1927 } else { 1928 *negp = 0; 1929 *lvalp = (unsigned long)val; 1930 } 1931 } 1932 return 0; 1933 } 1934 1935 /** 1936 * proc_dointvec_minmax - read a vector of integers with min/max values 1937 * @table: the sysctl table 1938 * @write: %TRUE if this is a write to the sysctl file 1939 * @filp: the file structure 1940 * @buffer: the user buffer 1941 * @lenp: the size of the user buffer 1942 * @ppos: file position 1943 * 1944 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 1945 * values from/to the user buffer, treated as an ASCII string. 1946 * 1947 * This routine will ensure the values are within the range specified by 1948 * table->extra1 (min) and table->extra2 (max). 1949 * 1950 * Returns 0 on success. 1951 */ 1952 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 1953 void __user *buffer, size_t *lenp, loff_t *ppos) 1954 { 1955 struct do_proc_dointvec_minmax_conv_param param = { 1956 .min = (int *) table->extra1, 1957 .max = (int *) table->extra2, 1958 }; 1959 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 1960 do_proc_dointvec_minmax_conv, ¶m); 1961 } 1962 1963 static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write, 1964 struct file *filp, 1965 void __user *buffer, 1966 size_t *lenp, loff_t *ppos, 1967 unsigned long convmul, 1968 unsigned long convdiv) 1969 { 1970 #define TMPBUFLEN 21 1971 unsigned long *i, *min, *max, val; 1972 int vleft, first=1, neg; 1973 size_t len, left; 1974 char buf[TMPBUFLEN], *p; 1975 char __user *s = buffer; 1976 1977 if (!data || !table->maxlen || !*lenp || 1978 (*ppos && !write)) { 1979 *lenp = 0; 1980 return 0; 1981 } 1982 1983 i = (unsigned long *) data; 1984 min = (unsigned long *) table->extra1; 1985 max = (unsigned long *) table->extra2; 1986 vleft = table->maxlen / sizeof(unsigned long); 1987 left = *lenp; 1988 1989 for (; left && vleft--; i++, min++, max++, first=0) { 1990 if (write) { 1991 while (left) { 1992 char c; 1993 if (get_user(c, s)) 1994 return -EFAULT; 1995 if (!isspace(c)) 1996 break; 1997 left--; 1998 s++; 1999 } 2000 if (!left) 2001 break; 2002 neg = 0; 2003 len = left; 2004 if (len > TMPBUFLEN-1) 2005 len = TMPBUFLEN-1; 2006 if (copy_from_user(buf, s, len)) 2007 return -EFAULT; 2008 buf[len] = 0; 2009 p = buf; 2010 if (*p == '-' && left > 1) { 2011 neg = 1; 2012 p++; 2013 } 2014 if (*p < '0' || *p > '9') 2015 break; 2016 val = simple_strtoul(p, &p, 0) * convmul / convdiv ; 2017 len = p-buf; 2018 if ((len < left) && *p && !isspace(*p)) 2019 break; 2020 if (neg) 2021 val = -val; 2022 s += len; 2023 left -= len; 2024 2025 if(neg) 2026 continue; 2027 if ((min && val < *min) || (max && val > *max)) 2028 continue; 2029 *i = val; 2030 } else { 2031 p = buf; 2032 if (!first) 2033 *p++ = '\t'; 2034 sprintf(p, "%lu", convdiv * (*i) / convmul); 2035 len = strlen(buf); 2036 if (len > left) 2037 len = left; 2038 if(copy_to_user(s, buf, len)) 2039 return -EFAULT; 2040 left -= len; 2041 s += len; 2042 } 2043 } 2044 2045 if (!write && !first && left) { 2046 if(put_user('\n', s)) 2047 return -EFAULT; 2048 left--, s++; 2049 } 2050 if (write) { 2051 while (left) { 2052 char c; 2053 if (get_user(c, s++)) 2054 return -EFAULT; 2055 if (!isspace(c)) 2056 break; 2057 left--; 2058 } 2059 } 2060 if (write && first) 2061 return -EINVAL; 2062 *lenp -= left; 2063 *ppos += *lenp; 2064 return 0; 2065 #undef TMPBUFLEN 2066 } 2067 2068 static int do_proc_doulongvec_minmax(ctl_table *table, int write, 2069 struct file *filp, 2070 void __user *buffer, 2071 size_t *lenp, loff_t *ppos, 2072 unsigned long convmul, 2073 unsigned long convdiv) 2074 { 2075 return __do_proc_doulongvec_minmax(table->data, table, write, 2076 filp, buffer, lenp, ppos, convmul, convdiv); 2077 } 2078 2079 /** 2080 * proc_doulongvec_minmax - read a vector of long integers with min/max values 2081 * @table: the sysctl table 2082 * @write: %TRUE if this is a write to the sysctl file 2083 * @filp: the file structure 2084 * @buffer: the user buffer 2085 * @lenp: the size of the user buffer 2086 * @ppos: file position 2087 * 2088 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 2089 * values from/to the user buffer, treated as an ASCII string. 2090 * 2091 * This routine will ensure the values are within the range specified by 2092 * table->extra1 (min) and table->extra2 (max). 2093 * 2094 * Returns 0 on success. 2095 */ 2096 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 2097 void __user *buffer, size_t *lenp, loff_t *ppos) 2098 { 2099 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l); 2100 } 2101 2102 /** 2103 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values 2104 * @table: the sysctl table 2105 * @write: %TRUE if this is a write to the sysctl file 2106 * @filp: the file structure 2107 * @buffer: the user buffer 2108 * @lenp: the size of the user buffer 2109 * @ppos: file position 2110 * 2111 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 2112 * values from/to the user buffer, treated as an ASCII string. The values 2113 * are treated as milliseconds, and converted to jiffies when they are stored. 2114 * 2115 * This routine will ensure the values are within the range specified by 2116 * table->extra1 (min) and table->extra2 (max). 2117 * 2118 * Returns 0 on success. 2119 */ 2120 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 2121 struct file *filp, 2122 void __user *buffer, 2123 size_t *lenp, loff_t *ppos) 2124 { 2125 return do_proc_doulongvec_minmax(table, write, filp, buffer, 2126 lenp, ppos, HZ, 1000l); 2127 } 2128 2129 2130 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp, 2131 int *valp, 2132 int write, void *data) 2133 { 2134 if (write) { 2135 if (*lvalp > LONG_MAX / HZ) 2136 return 1; 2137 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ); 2138 } else { 2139 int val = *valp; 2140 unsigned long lval; 2141 if (val < 0) { 2142 *negp = -1; 2143 lval = (unsigned long)-val; 2144 } else { 2145 *negp = 0; 2146 lval = (unsigned long)val; 2147 } 2148 *lvalp = lval / HZ; 2149 } 2150 return 0; 2151 } 2152 2153 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp, 2154 int *valp, 2155 int write, void *data) 2156 { 2157 if (write) { 2158 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ) 2159 return 1; 2160 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp); 2161 } else { 2162 int val = *valp; 2163 unsigned long lval; 2164 if (val < 0) { 2165 *negp = -1; 2166 lval = (unsigned long)-val; 2167 } else { 2168 *negp = 0; 2169 lval = (unsigned long)val; 2170 } 2171 *lvalp = jiffies_to_clock_t(lval); 2172 } 2173 return 0; 2174 } 2175 2176 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp, 2177 int *valp, 2178 int write, void *data) 2179 { 2180 if (write) { 2181 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp); 2182 } else { 2183 int val = *valp; 2184 unsigned long lval; 2185 if (val < 0) { 2186 *negp = -1; 2187 lval = (unsigned long)-val; 2188 } else { 2189 *negp = 0; 2190 lval = (unsigned long)val; 2191 } 2192 *lvalp = jiffies_to_msecs(lval); 2193 } 2194 return 0; 2195 } 2196 2197 /** 2198 * proc_dointvec_jiffies - read a vector of integers as seconds 2199 * @table: the sysctl table 2200 * @write: %TRUE if this is a write to the sysctl file 2201 * @filp: the file structure 2202 * @buffer: the user buffer 2203 * @lenp: the size of the user buffer 2204 * @ppos: file position 2205 * 2206 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2207 * values from/to the user buffer, treated as an ASCII string. 2208 * The values read are assumed to be in seconds, and are converted into 2209 * jiffies. 2210 * 2211 * Returns 0 on success. 2212 */ 2213 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2214 void __user *buffer, size_t *lenp, loff_t *ppos) 2215 { 2216 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2217 do_proc_dointvec_jiffies_conv,NULL); 2218 } 2219 2220 /** 2221 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds 2222 * @table: the sysctl table 2223 * @write: %TRUE if this is a write to the sysctl file 2224 * @filp: the file structure 2225 * @buffer: the user buffer 2226 * @lenp: the size of the user buffer 2227 * @ppos: pointer to the file position 2228 * 2229 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2230 * values from/to the user buffer, treated as an ASCII string. 2231 * The values read are assumed to be in 1/USER_HZ seconds, and 2232 * are converted into jiffies. 2233 * 2234 * Returns 0 on success. 2235 */ 2236 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2237 void __user *buffer, size_t *lenp, loff_t *ppos) 2238 { 2239 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2240 do_proc_dointvec_userhz_jiffies_conv,NULL); 2241 } 2242 2243 /** 2244 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds 2245 * @table: the sysctl table 2246 * @write: %TRUE if this is a write to the sysctl file 2247 * @filp: the file structure 2248 * @buffer: the user buffer 2249 * @lenp: the size of the user buffer 2250 * @ppos: file position 2251 * @ppos: the current position in the file 2252 * 2253 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2254 * values from/to the user buffer, treated as an ASCII string. 2255 * The values read are assumed to be in 1/1000 seconds, and 2256 * are converted into jiffies. 2257 * 2258 * Returns 0 on success. 2259 */ 2260 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2261 void __user *buffer, size_t *lenp, loff_t *ppos) 2262 { 2263 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 2264 do_proc_dointvec_ms_jiffies_conv, NULL); 2265 } 2266 2267 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp, 2268 void __user *buffer, size_t *lenp, loff_t *ppos) 2269 { 2270 struct pid *new_pid; 2271 pid_t tmp; 2272 int r; 2273 2274 tmp = pid_nr(cad_pid); 2275 2276 r = __do_proc_dointvec(&tmp, table, write, filp, buffer, 2277 lenp, ppos, NULL, NULL); 2278 if (r || !write) 2279 return r; 2280 2281 new_pid = find_get_pid(tmp); 2282 if (!new_pid) 2283 return -ESRCH; 2284 2285 put_pid(xchg(&cad_pid, new_pid)); 2286 return 0; 2287 } 2288 2289 #else /* CONFIG_PROC_FS */ 2290 2291 int proc_dostring(ctl_table *table, int write, struct file *filp, 2292 void __user *buffer, size_t *lenp, loff_t *ppos) 2293 { 2294 return -ENOSYS; 2295 } 2296 2297 int proc_dointvec(ctl_table *table, int write, struct file *filp, 2298 void __user *buffer, size_t *lenp, loff_t *ppos) 2299 { 2300 return -ENOSYS; 2301 } 2302 2303 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 2304 void __user *buffer, size_t *lenp, loff_t *ppos) 2305 { 2306 return -ENOSYS; 2307 } 2308 2309 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 2310 void __user *buffer, size_t *lenp, loff_t *ppos) 2311 { 2312 return -ENOSYS; 2313 } 2314 2315 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2316 void __user *buffer, size_t *lenp, loff_t *ppos) 2317 { 2318 return -ENOSYS; 2319 } 2320 2321 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2322 void __user *buffer, size_t *lenp, loff_t *ppos) 2323 { 2324 return -ENOSYS; 2325 } 2326 2327 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2328 void __user *buffer, size_t *lenp, loff_t *ppos) 2329 { 2330 return -ENOSYS; 2331 } 2332 2333 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 2334 void __user *buffer, size_t *lenp, loff_t *ppos) 2335 { 2336 return -ENOSYS; 2337 } 2338 2339 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 2340 struct file *filp, 2341 void __user *buffer, 2342 size_t *lenp, loff_t *ppos) 2343 { 2344 return -ENOSYS; 2345 } 2346 2347 2348 #endif /* CONFIG_PROC_FS */ 2349 2350 2351 #ifdef CONFIG_SYSCTL_SYSCALL 2352 /* 2353 * General sysctl support routines 2354 */ 2355 2356 /* The generic string strategy routine: */ 2357 int sysctl_string(ctl_table *table, int __user *name, int nlen, 2358 void __user *oldval, size_t __user *oldlenp, 2359 void __user *newval, size_t newlen) 2360 { 2361 if (!table->data || !table->maxlen) 2362 return -ENOTDIR; 2363 2364 if (oldval && oldlenp) { 2365 size_t bufsize; 2366 if (get_user(bufsize, oldlenp)) 2367 return -EFAULT; 2368 if (bufsize) { 2369 size_t len = strlen(table->data), copied; 2370 2371 /* This shouldn't trigger for a well-formed sysctl */ 2372 if (len > table->maxlen) 2373 len = table->maxlen; 2374 2375 /* Copy up to a max of bufsize-1 bytes of the string */ 2376 copied = (len >= bufsize) ? bufsize - 1 : len; 2377 2378 if (copy_to_user(oldval, table->data, copied) || 2379 put_user(0, (char __user *)(oldval + copied))) 2380 return -EFAULT; 2381 if (put_user(len, oldlenp)) 2382 return -EFAULT; 2383 } 2384 } 2385 if (newval && newlen) { 2386 size_t len = newlen; 2387 if (len > table->maxlen) 2388 len = table->maxlen; 2389 if(copy_from_user(table->data, newval, len)) 2390 return -EFAULT; 2391 if (len == table->maxlen) 2392 len--; 2393 ((char *) table->data)[len] = 0; 2394 } 2395 return 1; 2396 } 2397 2398 /* 2399 * This function makes sure that all of the integers in the vector 2400 * are between the minimum and maximum values given in the arrays 2401 * table->extra1 and table->extra2, respectively. 2402 */ 2403 int sysctl_intvec(ctl_table *table, int __user *name, int nlen, 2404 void __user *oldval, size_t __user *oldlenp, 2405 void __user *newval, size_t newlen) 2406 { 2407 2408 if (newval && newlen) { 2409 int __user *vec = (int __user *) newval; 2410 int *min = (int *) table->extra1; 2411 int *max = (int *) table->extra2; 2412 size_t length; 2413 int i; 2414 2415 if (newlen % sizeof(int) != 0) 2416 return -EINVAL; 2417 2418 if (!table->extra1 && !table->extra2) 2419 return 0; 2420 2421 if (newlen > table->maxlen) 2422 newlen = table->maxlen; 2423 length = newlen / sizeof(int); 2424 2425 for (i = 0; i < length; i++) { 2426 int value; 2427 if (get_user(value, vec + i)) 2428 return -EFAULT; 2429 if (min && value < min[i]) 2430 return -EINVAL; 2431 if (max && value > max[i]) 2432 return -EINVAL; 2433 } 2434 } 2435 return 0; 2436 } 2437 2438 /* Strategy function to convert jiffies to seconds */ 2439 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen, 2440 void __user *oldval, size_t __user *oldlenp, 2441 void __user *newval, size_t newlen) 2442 { 2443 if (oldval && oldlenp) { 2444 size_t olen; 2445 2446 if (get_user(olen, oldlenp)) 2447 return -EFAULT; 2448 if (olen) { 2449 int val; 2450 2451 if (olen < sizeof(int)) 2452 return -EINVAL; 2453 2454 val = *(int *)(table->data) / HZ; 2455 if (put_user(val, (int __user *)oldval)) 2456 return -EFAULT; 2457 if (put_user(sizeof(int), oldlenp)) 2458 return -EFAULT; 2459 } 2460 } 2461 if (newval && newlen) { 2462 int new; 2463 if (newlen != sizeof(int)) 2464 return -EINVAL; 2465 if (get_user(new, (int __user *)newval)) 2466 return -EFAULT; 2467 *(int *)(table->data) = new*HZ; 2468 } 2469 return 1; 2470 } 2471 2472 /* Strategy function to convert jiffies to seconds */ 2473 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, 2474 void __user *oldval, size_t __user *oldlenp, 2475 void __user *newval, size_t newlen) 2476 { 2477 if (oldval && oldlenp) { 2478 size_t olen; 2479 2480 if (get_user(olen, oldlenp)) 2481 return -EFAULT; 2482 if (olen) { 2483 int val; 2484 2485 if (olen < sizeof(int)) 2486 return -EINVAL; 2487 2488 val = jiffies_to_msecs(*(int *)(table->data)); 2489 if (put_user(val, (int __user *)oldval)) 2490 return -EFAULT; 2491 if (put_user(sizeof(int), oldlenp)) 2492 return -EFAULT; 2493 } 2494 } 2495 if (newval && newlen) { 2496 int new; 2497 if (newlen != sizeof(int)) 2498 return -EINVAL; 2499 if (get_user(new, (int __user *)newval)) 2500 return -EFAULT; 2501 *(int *)(table->data) = msecs_to_jiffies(new); 2502 } 2503 return 1; 2504 } 2505 2506 2507 2508 #else /* CONFIG_SYSCTL_SYSCALL */ 2509 2510 2511 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 2512 { 2513 static int msg_count; 2514 struct __sysctl_args tmp; 2515 int name[CTL_MAXNAME]; 2516 int i; 2517 2518 /* Read in the sysctl name for better debug message logging */ 2519 if (copy_from_user(&tmp, args, sizeof(tmp))) 2520 return -EFAULT; 2521 if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME) 2522 return -ENOTDIR; 2523 for (i = 0; i < tmp.nlen; i++) 2524 if (get_user(name[i], tmp.name + i)) 2525 return -EFAULT; 2526 2527 /* Ignore accesses to kernel.version */ 2528 if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION)) 2529 goto out; 2530 2531 if (msg_count < 5) { 2532 msg_count++; 2533 printk(KERN_INFO 2534 "warning: process `%s' used the removed sysctl " 2535 "system call with ", current->comm); 2536 for (i = 0; i < tmp.nlen; i++) 2537 printk("%d.", name[i]); 2538 printk("\n"); 2539 } 2540 out: 2541 return -ENOSYS; 2542 } 2543 2544 int sysctl_string(ctl_table *table, int __user *name, int nlen, 2545 void __user *oldval, size_t __user *oldlenp, 2546 void __user *newval, size_t newlen) 2547 { 2548 return -ENOSYS; 2549 } 2550 2551 int sysctl_intvec(ctl_table *table, int __user *name, int nlen, 2552 void __user *oldval, size_t __user *oldlenp, 2553 void __user *newval, size_t newlen) 2554 { 2555 return -ENOSYS; 2556 } 2557 2558 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen, 2559 void __user *oldval, size_t __user *oldlenp, 2560 void __user *newval, size_t newlen) 2561 { 2562 return -ENOSYS; 2563 } 2564 2565 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, 2566 void __user *oldval, size_t __user *oldlenp, 2567 void __user *newval, size_t newlen) 2568 { 2569 return -ENOSYS; 2570 } 2571 2572 #endif /* CONFIG_SYSCTL_SYSCALL */ 2573 2574 /* 2575 * No sense putting this after each symbol definition, twice, 2576 * exception granted :-) 2577 */ 2578 EXPORT_SYMBOL(proc_dointvec); 2579 EXPORT_SYMBOL(proc_dointvec_jiffies); 2580 EXPORT_SYMBOL(proc_dointvec_minmax); 2581 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies); 2582 EXPORT_SYMBOL(proc_dointvec_ms_jiffies); 2583 EXPORT_SYMBOL(proc_dostring); 2584 EXPORT_SYMBOL(proc_doulongvec_minmax); 2585 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax); 2586 EXPORT_SYMBOL(register_sysctl_table); 2587 EXPORT_SYMBOL(sysctl_intvec); 2588 EXPORT_SYMBOL(sysctl_jiffies); 2589 EXPORT_SYMBOL(sysctl_ms_jiffies); 2590 EXPORT_SYMBOL(sysctl_string); 2591 EXPORT_SYMBOL(unregister_sysctl_table); 2592