1 /* 2 * sysctl.c: General linux system control interface 3 * 4 * Begun 24 March 1995, Stephen Tweedie 5 * Added /proc support, Dec 1995 6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas. 7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver. 8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver. 9 * Dynamic registration fixes, Stephen Tweedie. 10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn. 11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris 12 * Horn. 13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer. 14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer. 15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill 16 * Wendling. 17 * The list_for_each() macro wasn't appropriate for the sysctl loop. 18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling 19 */ 20 21 #include <linux/module.h> 22 #include <linux/mm.h> 23 #include <linux/swap.h> 24 #include <linux/slab.h> 25 #include <linux/sysctl.h> 26 #include <linux/proc_fs.h> 27 #include <linux/capability.h> 28 #include <linux/ctype.h> 29 #include <linux/utsname.h> 30 #include <linux/capability.h> 31 #include <linux/smp_lock.h> 32 #include <linux/fs.h> 33 #include <linux/init.h> 34 #include <linux/kernel.h> 35 #include <linux/kobject.h> 36 #include <linux/net.h> 37 #include <linux/sysrq.h> 38 #include <linux/highuid.h> 39 #include <linux/writeback.h> 40 #include <linux/hugetlb.h> 41 #include <linux/security.h> 42 #include <linux/initrd.h> 43 #include <linux/times.h> 44 #include <linux/limits.h> 45 #include <linux/dcache.h> 46 #include <linux/syscalls.h> 47 #include <linux/nfs_fs.h> 48 #include <linux/acpi.h> 49 #include <linux/reboot.h> 50 51 #include <asm/uaccess.h> 52 #include <asm/processor.h> 53 54 #ifdef CONFIG_X86 55 #include <asm/nmi.h> 56 #include <asm/stacktrace.h> 57 #endif 58 59 #if defined(CONFIG_SYSCTL) 60 61 /* External variables not in a header file. */ 62 extern int C_A_D; 63 extern int print_fatal_signals; 64 extern int sysctl_overcommit_memory; 65 extern int sysctl_overcommit_ratio; 66 extern int sysctl_panic_on_oom; 67 extern int max_threads; 68 extern int core_uses_pid; 69 extern int suid_dumpable; 70 extern char core_pattern[]; 71 extern int pid_max; 72 extern int min_free_kbytes; 73 extern int printk_ratelimit_jiffies; 74 extern int printk_ratelimit_burst; 75 extern int pid_max_min, pid_max_max; 76 extern int sysctl_drop_caches; 77 extern int percpu_pagelist_fraction; 78 extern int compat_log; 79 extern int maps_protect; 80 extern int sysctl_stat_interval; 81 extern int audit_argv_kb; 82 83 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */ 84 static int maxolduid = 65535; 85 static int minolduid; 86 static int min_percpu_pagelist_fract = 8; 87 88 static int ngroups_max = NGROUPS_MAX; 89 90 #ifdef CONFIG_KMOD 91 extern char modprobe_path[]; 92 #endif 93 #ifdef CONFIG_CHR_DEV_SG 94 extern int sg_big_buff; 95 #endif 96 97 #ifdef __sparc__ 98 extern char reboot_command []; 99 extern int stop_a_enabled; 100 extern int scons_pwroff; 101 #endif 102 103 #ifdef __hppa__ 104 extern int pwrsw_enabled; 105 extern int unaligned_enabled; 106 #endif 107 108 #ifdef CONFIG_S390 109 #ifdef CONFIG_MATHEMU 110 extern int sysctl_ieee_emulation_warnings; 111 #endif 112 extern int sysctl_userprocess_debug; 113 extern int spin_retry; 114 #endif 115 116 extern int sysctl_hz_timer; 117 118 #ifdef CONFIG_BSD_PROCESS_ACCT 119 extern int acct_parm[]; 120 #endif 121 122 #ifdef CONFIG_IA64 123 extern int no_unaligned_warning; 124 #endif 125 126 #ifdef CONFIG_RT_MUTEXES 127 extern int max_lock_depth; 128 #endif 129 130 #ifdef CONFIG_SYSCTL_SYSCALL 131 static int parse_table(int __user *, int, void __user *, size_t __user *, 132 void __user *, size_t, ctl_table *); 133 #endif 134 135 136 #ifdef CONFIG_PROC_SYSCTL 137 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp, 138 void __user *buffer, size_t *lenp, loff_t *ppos); 139 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp, 140 void __user *buffer, size_t *lenp, loff_t *ppos); 141 #endif 142 143 static ctl_table root_table[]; 144 static struct ctl_table_header root_table_header = 145 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) }; 146 147 static ctl_table kern_table[]; 148 static ctl_table vm_table[]; 149 static ctl_table fs_table[]; 150 static ctl_table debug_table[]; 151 static ctl_table dev_table[]; 152 extern ctl_table random_table[]; 153 #ifdef CONFIG_UNIX98_PTYS 154 extern ctl_table pty_table[]; 155 #endif 156 #ifdef CONFIG_INOTIFY_USER 157 extern ctl_table inotify_table[]; 158 #endif 159 160 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 161 int sysctl_legacy_va_layout; 162 #endif 163 164 extern int prove_locking; 165 extern int lock_stat; 166 167 /* The default sysctl tables: */ 168 169 static ctl_table root_table[] = { 170 { 171 .ctl_name = CTL_KERN, 172 .procname = "kernel", 173 .mode = 0555, 174 .child = kern_table, 175 }, 176 { 177 .ctl_name = CTL_VM, 178 .procname = "vm", 179 .mode = 0555, 180 .child = vm_table, 181 }, 182 #ifdef CONFIG_NET 183 { 184 .ctl_name = CTL_NET, 185 .procname = "net", 186 .mode = 0555, 187 .child = net_table, 188 }, 189 #endif 190 { 191 .ctl_name = CTL_FS, 192 .procname = "fs", 193 .mode = 0555, 194 .child = fs_table, 195 }, 196 { 197 .ctl_name = CTL_DEBUG, 198 .procname = "debug", 199 .mode = 0555, 200 .child = debug_table, 201 }, 202 { 203 .ctl_name = CTL_DEV, 204 .procname = "dev", 205 .mode = 0555, 206 .child = dev_table, 207 }, 208 /* 209 * NOTE: do not add new entries to this table unless you have read 210 * Documentation/sysctl/ctl_unnumbered.txt 211 */ 212 { .ctl_name = 0 } 213 }; 214 215 #ifdef CONFIG_SCHED_DEBUG 216 static unsigned long min_sched_granularity_ns = 100000; /* 100 usecs */ 217 static unsigned long max_sched_granularity_ns = 1000000000; /* 1 second */ 218 static unsigned long min_wakeup_granularity_ns; /* 0 usecs */ 219 static unsigned long max_wakeup_granularity_ns = 1000000000; /* 1 second */ 220 #endif 221 222 static ctl_table kern_table[] = { 223 #ifdef CONFIG_SCHED_DEBUG 224 { 225 .ctl_name = CTL_UNNUMBERED, 226 .procname = "sched_granularity_ns", 227 .data = &sysctl_sched_granularity, 228 .maxlen = sizeof(unsigned int), 229 .mode = 0644, 230 .proc_handler = &proc_dointvec_minmax, 231 .strategy = &sysctl_intvec, 232 .extra1 = &min_sched_granularity_ns, 233 .extra2 = &max_sched_granularity_ns, 234 }, 235 { 236 .ctl_name = CTL_UNNUMBERED, 237 .procname = "sched_wakeup_granularity_ns", 238 .data = &sysctl_sched_wakeup_granularity, 239 .maxlen = sizeof(unsigned int), 240 .mode = 0644, 241 .proc_handler = &proc_dointvec_minmax, 242 .strategy = &sysctl_intvec, 243 .extra1 = &min_wakeup_granularity_ns, 244 .extra2 = &max_wakeup_granularity_ns, 245 }, 246 { 247 .ctl_name = CTL_UNNUMBERED, 248 .procname = "sched_batch_wakeup_granularity_ns", 249 .data = &sysctl_sched_batch_wakeup_granularity, 250 .maxlen = sizeof(unsigned int), 251 .mode = 0644, 252 .proc_handler = &proc_dointvec_minmax, 253 .strategy = &sysctl_intvec, 254 .extra1 = &min_wakeup_granularity_ns, 255 .extra2 = &max_wakeup_granularity_ns, 256 }, 257 { 258 .ctl_name = CTL_UNNUMBERED, 259 .procname = "sched_stat_granularity_ns", 260 .data = &sysctl_sched_stat_granularity, 261 .maxlen = sizeof(unsigned int), 262 .mode = 0644, 263 .proc_handler = &proc_dointvec_minmax, 264 .strategy = &sysctl_intvec, 265 .extra1 = &min_wakeup_granularity_ns, 266 .extra2 = &max_wakeup_granularity_ns, 267 }, 268 { 269 .ctl_name = CTL_UNNUMBERED, 270 .procname = "sched_runtime_limit_ns", 271 .data = &sysctl_sched_runtime_limit, 272 .maxlen = sizeof(unsigned int), 273 .mode = 0644, 274 .proc_handler = &proc_dointvec_minmax, 275 .strategy = &sysctl_intvec, 276 .extra1 = &min_sched_granularity_ns, 277 .extra2 = &max_sched_granularity_ns, 278 }, 279 { 280 .ctl_name = CTL_UNNUMBERED, 281 .procname = "sched_child_runs_first", 282 .data = &sysctl_sched_child_runs_first, 283 .maxlen = sizeof(unsigned int), 284 .mode = 0644, 285 .proc_handler = &proc_dointvec, 286 }, 287 #ifdef CONFIG_PROVE_LOCKING 288 { 289 .ctl_name = CTL_UNNUMBERED, 290 .procname = "prove_locking", 291 .data = &prove_locking, 292 .maxlen = sizeof(int), 293 .mode = 0644, 294 .proc_handler = &proc_dointvec, 295 }, 296 #endif 297 #ifdef CONFIG_LOCK_STAT 298 { 299 .ctl_name = CTL_UNNUMBERED, 300 .procname = "lock_stat", 301 .data = &lock_stat, 302 .maxlen = sizeof(int), 303 .mode = 0644, 304 .proc_handler = &proc_dointvec, 305 }, 306 #endif 307 { 308 .ctl_name = CTL_UNNUMBERED, 309 .procname = "sched_features", 310 .data = &sysctl_sched_features, 311 .maxlen = sizeof(unsigned int), 312 .mode = 0644, 313 .proc_handler = &proc_dointvec, 314 }, 315 #endif 316 { 317 .ctl_name = KERN_PANIC, 318 .procname = "panic", 319 .data = &panic_timeout, 320 .maxlen = sizeof(int), 321 .mode = 0644, 322 .proc_handler = &proc_dointvec, 323 }, 324 { 325 .ctl_name = KERN_CORE_USES_PID, 326 .procname = "core_uses_pid", 327 .data = &core_uses_pid, 328 .maxlen = sizeof(int), 329 .mode = 0644, 330 .proc_handler = &proc_dointvec, 331 }, 332 #ifdef CONFIG_AUDITSYSCALL 333 { 334 .ctl_name = CTL_UNNUMBERED, 335 .procname = "audit_argv_kb", 336 .data = &audit_argv_kb, 337 .maxlen = sizeof(int), 338 .mode = 0644, 339 .proc_handler = &proc_dointvec, 340 }, 341 #endif 342 { 343 .ctl_name = KERN_CORE_PATTERN, 344 .procname = "core_pattern", 345 .data = core_pattern, 346 .maxlen = CORENAME_MAX_SIZE, 347 .mode = 0644, 348 .proc_handler = &proc_dostring, 349 .strategy = &sysctl_string, 350 }, 351 #ifdef CONFIG_PROC_SYSCTL 352 { 353 .ctl_name = KERN_TAINTED, 354 .procname = "tainted", 355 .data = &tainted, 356 .maxlen = sizeof(int), 357 .mode = 0644, 358 .proc_handler = &proc_dointvec_taint, 359 }, 360 #endif 361 { 362 .ctl_name = KERN_CAP_BSET, 363 .procname = "cap-bound", 364 .data = &cap_bset, 365 .maxlen = sizeof(kernel_cap_t), 366 .mode = 0600, 367 .proc_handler = &proc_dointvec_bset, 368 }, 369 #ifdef CONFIG_BLK_DEV_INITRD 370 { 371 .ctl_name = KERN_REALROOTDEV, 372 .procname = "real-root-dev", 373 .data = &real_root_dev, 374 .maxlen = sizeof(int), 375 .mode = 0644, 376 .proc_handler = &proc_dointvec, 377 }, 378 #endif 379 { 380 .ctl_name = CTL_UNNUMBERED, 381 .procname = "print-fatal-signals", 382 .data = &print_fatal_signals, 383 .maxlen = sizeof(int), 384 .mode = 0644, 385 .proc_handler = &proc_dointvec, 386 }, 387 #ifdef __sparc__ 388 { 389 .ctl_name = KERN_SPARC_REBOOT, 390 .procname = "reboot-cmd", 391 .data = reboot_command, 392 .maxlen = 256, 393 .mode = 0644, 394 .proc_handler = &proc_dostring, 395 .strategy = &sysctl_string, 396 }, 397 { 398 .ctl_name = KERN_SPARC_STOP_A, 399 .procname = "stop-a", 400 .data = &stop_a_enabled, 401 .maxlen = sizeof (int), 402 .mode = 0644, 403 .proc_handler = &proc_dointvec, 404 }, 405 { 406 .ctl_name = KERN_SPARC_SCONS_PWROFF, 407 .procname = "scons-poweroff", 408 .data = &scons_pwroff, 409 .maxlen = sizeof (int), 410 .mode = 0644, 411 .proc_handler = &proc_dointvec, 412 }, 413 #endif 414 #ifdef __hppa__ 415 { 416 .ctl_name = KERN_HPPA_PWRSW, 417 .procname = "soft-power", 418 .data = &pwrsw_enabled, 419 .maxlen = sizeof (int), 420 .mode = 0644, 421 .proc_handler = &proc_dointvec, 422 }, 423 { 424 .ctl_name = KERN_HPPA_UNALIGNED, 425 .procname = "unaligned-trap", 426 .data = &unaligned_enabled, 427 .maxlen = sizeof (int), 428 .mode = 0644, 429 .proc_handler = &proc_dointvec, 430 }, 431 #endif 432 { 433 .ctl_name = KERN_CTLALTDEL, 434 .procname = "ctrl-alt-del", 435 .data = &C_A_D, 436 .maxlen = sizeof(int), 437 .mode = 0644, 438 .proc_handler = &proc_dointvec, 439 }, 440 { 441 .ctl_name = KERN_PRINTK, 442 .procname = "printk", 443 .data = &console_loglevel, 444 .maxlen = 4*sizeof(int), 445 .mode = 0644, 446 .proc_handler = &proc_dointvec, 447 }, 448 #ifdef CONFIG_KMOD 449 { 450 .ctl_name = KERN_MODPROBE, 451 .procname = "modprobe", 452 .data = &modprobe_path, 453 .maxlen = KMOD_PATH_LEN, 454 .mode = 0644, 455 .proc_handler = &proc_dostring, 456 .strategy = &sysctl_string, 457 }, 458 #endif 459 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET) 460 { 461 .ctl_name = KERN_HOTPLUG, 462 .procname = "hotplug", 463 .data = &uevent_helper, 464 .maxlen = UEVENT_HELPER_PATH_LEN, 465 .mode = 0644, 466 .proc_handler = &proc_dostring, 467 .strategy = &sysctl_string, 468 }, 469 #endif 470 #ifdef CONFIG_CHR_DEV_SG 471 { 472 .ctl_name = KERN_SG_BIG_BUFF, 473 .procname = "sg-big-buff", 474 .data = &sg_big_buff, 475 .maxlen = sizeof (int), 476 .mode = 0444, 477 .proc_handler = &proc_dointvec, 478 }, 479 #endif 480 #ifdef CONFIG_BSD_PROCESS_ACCT 481 { 482 .ctl_name = KERN_ACCT, 483 .procname = "acct", 484 .data = &acct_parm, 485 .maxlen = 3*sizeof(int), 486 .mode = 0644, 487 .proc_handler = &proc_dointvec, 488 }, 489 #endif 490 #ifdef CONFIG_MAGIC_SYSRQ 491 { 492 .ctl_name = KERN_SYSRQ, 493 .procname = "sysrq", 494 .data = &__sysrq_enabled, 495 .maxlen = sizeof (int), 496 .mode = 0644, 497 .proc_handler = &proc_dointvec, 498 }, 499 #endif 500 #ifdef CONFIG_PROC_SYSCTL 501 { 502 .ctl_name = KERN_CADPID, 503 .procname = "cad_pid", 504 .data = NULL, 505 .maxlen = sizeof (int), 506 .mode = 0600, 507 .proc_handler = &proc_do_cad_pid, 508 }, 509 #endif 510 { 511 .ctl_name = KERN_MAX_THREADS, 512 .procname = "threads-max", 513 .data = &max_threads, 514 .maxlen = sizeof(int), 515 .mode = 0644, 516 .proc_handler = &proc_dointvec, 517 }, 518 { 519 .ctl_name = KERN_RANDOM, 520 .procname = "random", 521 .mode = 0555, 522 .child = random_table, 523 }, 524 #ifdef CONFIG_UNIX98_PTYS 525 { 526 .ctl_name = KERN_PTY, 527 .procname = "pty", 528 .mode = 0555, 529 .child = pty_table, 530 }, 531 #endif 532 { 533 .ctl_name = KERN_OVERFLOWUID, 534 .procname = "overflowuid", 535 .data = &overflowuid, 536 .maxlen = sizeof(int), 537 .mode = 0644, 538 .proc_handler = &proc_dointvec_minmax, 539 .strategy = &sysctl_intvec, 540 .extra1 = &minolduid, 541 .extra2 = &maxolduid, 542 }, 543 { 544 .ctl_name = KERN_OVERFLOWGID, 545 .procname = "overflowgid", 546 .data = &overflowgid, 547 .maxlen = sizeof(int), 548 .mode = 0644, 549 .proc_handler = &proc_dointvec_minmax, 550 .strategy = &sysctl_intvec, 551 .extra1 = &minolduid, 552 .extra2 = &maxolduid, 553 }, 554 #ifdef CONFIG_S390 555 #ifdef CONFIG_MATHEMU 556 { 557 .ctl_name = KERN_IEEE_EMULATION_WARNINGS, 558 .procname = "ieee_emulation_warnings", 559 .data = &sysctl_ieee_emulation_warnings, 560 .maxlen = sizeof(int), 561 .mode = 0644, 562 .proc_handler = &proc_dointvec, 563 }, 564 #endif 565 #ifdef CONFIG_NO_IDLE_HZ 566 { 567 .ctl_name = KERN_HZ_TIMER, 568 .procname = "hz_timer", 569 .data = &sysctl_hz_timer, 570 .maxlen = sizeof(int), 571 .mode = 0644, 572 .proc_handler = &proc_dointvec, 573 }, 574 #endif 575 { 576 .ctl_name = KERN_S390_USER_DEBUG_LOGGING, 577 .procname = "userprocess_debug", 578 .data = &sysctl_userprocess_debug, 579 .maxlen = sizeof(int), 580 .mode = 0644, 581 .proc_handler = &proc_dointvec, 582 }, 583 #endif 584 { 585 .ctl_name = KERN_PIDMAX, 586 .procname = "pid_max", 587 .data = &pid_max, 588 .maxlen = sizeof (int), 589 .mode = 0644, 590 .proc_handler = &proc_dointvec_minmax, 591 .strategy = sysctl_intvec, 592 .extra1 = &pid_max_min, 593 .extra2 = &pid_max_max, 594 }, 595 { 596 .ctl_name = KERN_PANIC_ON_OOPS, 597 .procname = "panic_on_oops", 598 .data = &panic_on_oops, 599 .maxlen = sizeof(int), 600 .mode = 0644, 601 .proc_handler = &proc_dointvec, 602 }, 603 { 604 .ctl_name = KERN_PRINTK_RATELIMIT, 605 .procname = "printk_ratelimit", 606 .data = &printk_ratelimit_jiffies, 607 .maxlen = sizeof(int), 608 .mode = 0644, 609 .proc_handler = &proc_dointvec_jiffies, 610 .strategy = &sysctl_jiffies, 611 }, 612 { 613 .ctl_name = KERN_PRINTK_RATELIMIT_BURST, 614 .procname = "printk_ratelimit_burst", 615 .data = &printk_ratelimit_burst, 616 .maxlen = sizeof(int), 617 .mode = 0644, 618 .proc_handler = &proc_dointvec, 619 }, 620 { 621 .ctl_name = KERN_NGROUPS_MAX, 622 .procname = "ngroups_max", 623 .data = &ngroups_max, 624 .maxlen = sizeof (int), 625 .mode = 0444, 626 .proc_handler = &proc_dointvec, 627 }, 628 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) 629 { 630 .ctl_name = KERN_UNKNOWN_NMI_PANIC, 631 .procname = "unknown_nmi_panic", 632 .data = &unknown_nmi_panic, 633 .maxlen = sizeof (int), 634 .mode = 0644, 635 .proc_handler = &proc_dointvec, 636 }, 637 { 638 .ctl_name = KERN_NMI_WATCHDOG, 639 .procname = "nmi_watchdog", 640 .data = &nmi_watchdog_enabled, 641 .maxlen = sizeof (int), 642 .mode = 0644, 643 .proc_handler = &proc_nmi_enabled, 644 }, 645 #endif 646 #if defined(CONFIG_X86) 647 { 648 .ctl_name = KERN_PANIC_ON_NMI, 649 .procname = "panic_on_unrecovered_nmi", 650 .data = &panic_on_unrecovered_nmi, 651 .maxlen = sizeof(int), 652 .mode = 0644, 653 .proc_handler = &proc_dointvec, 654 }, 655 { 656 .ctl_name = KERN_BOOTLOADER_TYPE, 657 .procname = "bootloader_type", 658 .data = &bootloader_type, 659 .maxlen = sizeof (int), 660 .mode = 0444, 661 .proc_handler = &proc_dointvec, 662 }, 663 { 664 .ctl_name = CTL_UNNUMBERED, 665 .procname = "kstack_depth_to_print", 666 .data = &kstack_depth_to_print, 667 .maxlen = sizeof(int), 668 .mode = 0644, 669 .proc_handler = &proc_dointvec, 670 }, 671 #endif 672 #if defined(CONFIG_MMU) 673 { 674 .ctl_name = KERN_RANDOMIZE, 675 .procname = "randomize_va_space", 676 .data = &randomize_va_space, 677 .maxlen = sizeof(int), 678 .mode = 0644, 679 .proc_handler = &proc_dointvec, 680 }, 681 #endif 682 #if defined(CONFIG_S390) && defined(CONFIG_SMP) 683 { 684 .ctl_name = KERN_SPIN_RETRY, 685 .procname = "spin_retry", 686 .data = &spin_retry, 687 .maxlen = sizeof (int), 688 .mode = 0644, 689 .proc_handler = &proc_dointvec, 690 }, 691 #endif 692 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86) 693 { 694 .ctl_name = KERN_ACPI_VIDEO_FLAGS, 695 .procname = "acpi_video_flags", 696 .data = &acpi_realmode_flags, 697 .maxlen = sizeof (unsigned long), 698 .mode = 0644, 699 .proc_handler = &proc_doulongvec_minmax, 700 }, 701 #endif 702 #ifdef CONFIG_IA64 703 { 704 .ctl_name = KERN_IA64_UNALIGNED, 705 .procname = "ignore-unaligned-usertrap", 706 .data = &no_unaligned_warning, 707 .maxlen = sizeof (int), 708 .mode = 0644, 709 .proc_handler = &proc_dointvec, 710 }, 711 #endif 712 #ifdef CONFIG_COMPAT 713 { 714 .ctl_name = KERN_COMPAT_LOG, 715 .procname = "compat-log", 716 .data = &compat_log, 717 .maxlen = sizeof (int), 718 .mode = 0644, 719 .proc_handler = &proc_dointvec, 720 }, 721 #endif 722 #ifdef CONFIG_RT_MUTEXES 723 { 724 .ctl_name = KERN_MAX_LOCK_DEPTH, 725 .procname = "max_lock_depth", 726 .data = &max_lock_depth, 727 .maxlen = sizeof(int), 728 .mode = 0644, 729 .proc_handler = &proc_dointvec, 730 }, 731 #endif 732 #ifdef CONFIG_PROC_FS 733 { 734 .ctl_name = CTL_UNNUMBERED, 735 .procname = "maps_protect", 736 .data = &maps_protect, 737 .maxlen = sizeof(int), 738 .mode = 0644, 739 .proc_handler = &proc_dointvec, 740 }, 741 #endif 742 { 743 .ctl_name = CTL_UNNUMBERED, 744 .procname = "poweroff_cmd", 745 .data = &poweroff_cmd, 746 .maxlen = POWEROFF_CMD_PATH_LEN, 747 .mode = 0644, 748 .proc_handler = &proc_dostring, 749 .strategy = &sysctl_string, 750 }, 751 /* 752 * NOTE: do not add new entries to this table unless you have read 753 * Documentation/sysctl/ctl_unnumbered.txt 754 */ 755 { .ctl_name = 0 } 756 }; 757 758 /* Constants for minimum and maximum testing in vm_table. 759 We use these as one-element integer vectors. */ 760 static int zero; 761 static int two = 2; 762 static int one_hundred = 100; 763 764 765 static ctl_table vm_table[] = { 766 { 767 .ctl_name = VM_OVERCOMMIT_MEMORY, 768 .procname = "overcommit_memory", 769 .data = &sysctl_overcommit_memory, 770 .maxlen = sizeof(sysctl_overcommit_memory), 771 .mode = 0644, 772 .proc_handler = &proc_dointvec, 773 }, 774 { 775 .ctl_name = VM_PANIC_ON_OOM, 776 .procname = "panic_on_oom", 777 .data = &sysctl_panic_on_oom, 778 .maxlen = sizeof(sysctl_panic_on_oom), 779 .mode = 0644, 780 .proc_handler = &proc_dointvec, 781 }, 782 { 783 .ctl_name = VM_OVERCOMMIT_RATIO, 784 .procname = "overcommit_ratio", 785 .data = &sysctl_overcommit_ratio, 786 .maxlen = sizeof(sysctl_overcommit_ratio), 787 .mode = 0644, 788 .proc_handler = &proc_dointvec, 789 }, 790 { 791 .ctl_name = VM_PAGE_CLUSTER, 792 .procname = "page-cluster", 793 .data = &page_cluster, 794 .maxlen = sizeof(int), 795 .mode = 0644, 796 .proc_handler = &proc_dointvec, 797 }, 798 { 799 .ctl_name = VM_DIRTY_BACKGROUND, 800 .procname = "dirty_background_ratio", 801 .data = &dirty_background_ratio, 802 .maxlen = sizeof(dirty_background_ratio), 803 .mode = 0644, 804 .proc_handler = &proc_dointvec_minmax, 805 .strategy = &sysctl_intvec, 806 .extra1 = &zero, 807 .extra2 = &one_hundred, 808 }, 809 { 810 .ctl_name = VM_DIRTY_RATIO, 811 .procname = "dirty_ratio", 812 .data = &vm_dirty_ratio, 813 .maxlen = sizeof(vm_dirty_ratio), 814 .mode = 0644, 815 .proc_handler = &proc_dointvec_minmax, 816 .strategy = &sysctl_intvec, 817 .extra1 = &zero, 818 .extra2 = &one_hundred, 819 }, 820 { 821 .ctl_name = VM_DIRTY_WB_CS, 822 .procname = "dirty_writeback_centisecs", 823 .data = &dirty_writeback_interval, 824 .maxlen = sizeof(dirty_writeback_interval), 825 .mode = 0644, 826 .proc_handler = &dirty_writeback_centisecs_handler, 827 }, 828 { 829 .ctl_name = VM_DIRTY_EXPIRE_CS, 830 .procname = "dirty_expire_centisecs", 831 .data = &dirty_expire_interval, 832 .maxlen = sizeof(dirty_expire_interval), 833 .mode = 0644, 834 .proc_handler = &proc_dointvec_userhz_jiffies, 835 }, 836 { 837 .ctl_name = VM_NR_PDFLUSH_THREADS, 838 .procname = "nr_pdflush_threads", 839 .data = &nr_pdflush_threads, 840 .maxlen = sizeof nr_pdflush_threads, 841 .mode = 0444 /* read-only*/, 842 .proc_handler = &proc_dointvec, 843 }, 844 { 845 .ctl_name = VM_SWAPPINESS, 846 .procname = "swappiness", 847 .data = &vm_swappiness, 848 .maxlen = sizeof(vm_swappiness), 849 .mode = 0644, 850 .proc_handler = &proc_dointvec_minmax, 851 .strategy = &sysctl_intvec, 852 .extra1 = &zero, 853 .extra2 = &one_hundred, 854 }, 855 #ifdef CONFIG_HUGETLB_PAGE 856 { 857 .ctl_name = VM_HUGETLB_PAGES, 858 .procname = "nr_hugepages", 859 .data = &max_huge_pages, 860 .maxlen = sizeof(unsigned long), 861 .mode = 0644, 862 .proc_handler = &hugetlb_sysctl_handler, 863 .extra1 = (void *)&hugetlb_zero, 864 .extra2 = (void *)&hugetlb_infinity, 865 }, 866 { 867 .ctl_name = VM_HUGETLB_GROUP, 868 .procname = "hugetlb_shm_group", 869 .data = &sysctl_hugetlb_shm_group, 870 .maxlen = sizeof(gid_t), 871 .mode = 0644, 872 .proc_handler = &proc_dointvec, 873 }, 874 { 875 .ctl_name = CTL_UNNUMBERED, 876 .procname = "hugepages_treat_as_movable", 877 .data = &hugepages_treat_as_movable, 878 .maxlen = sizeof(int), 879 .mode = 0644, 880 .proc_handler = &hugetlb_treat_movable_handler, 881 }, 882 #endif 883 { 884 .ctl_name = VM_LOWMEM_RESERVE_RATIO, 885 .procname = "lowmem_reserve_ratio", 886 .data = &sysctl_lowmem_reserve_ratio, 887 .maxlen = sizeof(sysctl_lowmem_reserve_ratio), 888 .mode = 0644, 889 .proc_handler = &lowmem_reserve_ratio_sysctl_handler, 890 .strategy = &sysctl_intvec, 891 }, 892 { 893 .ctl_name = VM_DROP_PAGECACHE, 894 .procname = "drop_caches", 895 .data = &sysctl_drop_caches, 896 .maxlen = sizeof(int), 897 .mode = 0644, 898 .proc_handler = drop_caches_sysctl_handler, 899 .strategy = &sysctl_intvec, 900 }, 901 { 902 .ctl_name = VM_MIN_FREE_KBYTES, 903 .procname = "min_free_kbytes", 904 .data = &min_free_kbytes, 905 .maxlen = sizeof(min_free_kbytes), 906 .mode = 0644, 907 .proc_handler = &min_free_kbytes_sysctl_handler, 908 .strategy = &sysctl_intvec, 909 .extra1 = &zero, 910 }, 911 { 912 .ctl_name = VM_PERCPU_PAGELIST_FRACTION, 913 .procname = "percpu_pagelist_fraction", 914 .data = &percpu_pagelist_fraction, 915 .maxlen = sizeof(percpu_pagelist_fraction), 916 .mode = 0644, 917 .proc_handler = &percpu_pagelist_fraction_sysctl_handler, 918 .strategy = &sysctl_intvec, 919 .extra1 = &min_percpu_pagelist_fract, 920 }, 921 #ifdef CONFIG_MMU 922 { 923 .ctl_name = VM_MAX_MAP_COUNT, 924 .procname = "max_map_count", 925 .data = &sysctl_max_map_count, 926 .maxlen = sizeof(sysctl_max_map_count), 927 .mode = 0644, 928 .proc_handler = &proc_dointvec 929 }, 930 #endif 931 { 932 .ctl_name = VM_LAPTOP_MODE, 933 .procname = "laptop_mode", 934 .data = &laptop_mode, 935 .maxlen = sizeof(laptop_mode), 936 .mode = 0644, 937 .proc_handler = &proc_dointvec_jiffies, 938 .strategy = &sysctl_jiffies, 939 }, 940 { 941 .ctl_name = VM_BLOCK_DUMP, 942 .procname = "block_dump", 943 .data = &block_dump, 944 .maxlen = sizeof(block_dump), 945 .mode = 0644, 946 .proc_handler = &proc_dointvec, 947 .strategy = &sysctl_intvec, 948 .extra1 = &zero, 949 }, 950 { 951 .ctl_name = VM_VFS_CACHE_PRESSURE, 952 .procname = "vfs_cache_pressure", 953 .data = &sysctl_vfs_cache_pressure, 954 .maxlen = sizeof(sysctl_vfs_cache_pressure), 955 .mode = 0644, 956 .proc_handler = &proc_dointvec, 957 .strategy = &sysctl_intvec, 958 .extra1 = &zero, 959 }, 960 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT 961 { 962 .ctl_name = VM_LEGACY_VA_LAYOUT, 963 .procname = "legacy_va_layout", 964 .data = &sysctl_legacy_va_layout, 965 .maxlen = sizeof(sysctl_legacy_va_layout), 966 .mode = 0644, 967 .proc_handler = &proc_dointvec, 968 .strategy = &sysctl_intvec, 969 .extra1 = &zero, 970 }, 971 #endif 972 #ifdef CONFIG_NUMA 973 { 974 .ctl_name = VM_ZONE_RECLAIM_MODE, 975 .procname = "zone_reclaim_mode", 976 .data = &zone_reclaim_mode, 977 .maxlen = sizeof(zone_reclaim_mode), 978 .mode = 0644, 979 .proc_handler = &proc_dointvec, 980 .strategy = &sysctl_intvec, 981 .extra1 = &zero, 982 }, 983 { 984 .ctl_name = VM_MIN_UNMAPPED, 985 .procname = "min_unmapped_ratio", 986 .data = &sysctl_min_unmapped_ratio, 987 .maxlen = sizeof(sysctl_min_unmapped_ratio), 988 .mode = 0644, 989 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler, 990 .strategy = &sysctl_intvec, 991 .extra1 = &zero, 992 .extra2 = &one_hundred, 993 }, 994 { 995 .ctl_name = VM_MIN_SLAB, 996 .procname = "min_slab_ratio", 997 .data = &sysctl_min_slab_ratio, 998 .maxlen = sizeof(sysctl_min_slab_ratio), 999 .mode = 0644, 1000 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler, 1001 .strategy = &sysctl_intvec, 1002 .extra1 = &zero, 1003 .extra2 = &one_hundred, 1004 }, 1005 #endif 1006 #ifdef CONFIG_SMP 1007 { 1008 .ctl_name = CTL_UNNUMBERED, 1009 .procname = "stat_interval", 1010 .data = &sysctl_stat_interval, 1011 .maxlen = sizeof(sysctl_stat_interval), 1012 .mode = 0644, 1013 .proc_handler = &proc_dointvec_jiffies, 1014 .strategy = &sysctl_jiffies, 1015 }, 1016 #endif 1017 #ifdef CONFIG_SECURITY 1018 { 1019 .ctl_name = CTL_UNNUMBERED, 1020 .procname = "mmap_min_addr", 1021 .data = &mmap_min_addr, 1022 .maxlen = sizeof(unsigned long), 1023 .mode = 0644, 1024 .proc_handler = &proc_doulongvec_minmax, 1025 }, 1026 #ifdef CONFIG_NUMA 1027 { 1028 .ctl_name = CTL_UNNUMBERED, 1029 .procname = "numa_zonelist_order", 1030 .data = &numa_zonelist_order, 1031 .maxlen = NUMA_ZONELIST_ORDER_LEN, 1032 .mode = 0644, 1033 .proc_handler = &numa_zonelist_order_handler, 1034 .strategy = &sysctl_string, 1035 }, 1036 #endif 1037 #endif 1038 #if defined(CONFIG_X86_32) || \ 1039 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL)) 1040 { 1041 .ctl_name = VM_VDSO_ENABLED, 1042 .procname = "vdso_enabled", 1043 .data = &vdso_enabled, 1044 .maxlen = sizeof(vdso_enabled), 1045 .mode = 0644, 1046 .proc_handler = &proc_dointvec, 1047 .strategy = &sysctl_intvec, 1048 .extra1 = &zero, 1049 }, 1050 #endif 1051 /* 1052 * NOTE: do not add new entries to this table unless you have read 1053 * Documentation/sysctl/ctl_unnumbered.txt 1054 */ 1055 { .ctl_name = 0 } 1056 }; 1057 1058 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) 1059 static ctl_table binfmt_misc_table[] = { 1060 { .ctl_name = 0 } 1061 }; 1062 #endif 1063 1064 static ctl_table fs_table[] = { 1065 { 1066 .ctl_name = FS_NRINODE, 1067 .procname = "inode-nr", 1068 .data = &inodes_stat, 1069 .maxlen = 2*sizeof(int), 1070 .mode = 0444, 1071 .proc_handler = &proc_dointvec, 1072 }, 1073 { 1074 .ctl_name = FS_STATINODE, 1075 .procname = "inode-state", 1076 .data = &inodes_stat, 1077 .maxlen = 7*sizeof(int), 1078 .mode = 0444, 1079 .proc_handler = &proc_dointvec, 1080 }, 1081 { 1082 .ctl_name = FS_NRFILE, 1083 .procname = "file-nr", 1084 .data = &files_stat, 1085 .maxlen = 3*sizeof(int), 1086 .mode = 0444, 1087 .proc_handler = &proc_nr_files, 1088 }, 1089 { 1090 .ctl_name = FS_MAXFILE, 1091 .procname = "file-max", 1092 .data = &files_stat.max_files, 1093 .maxlen = sizeof(int), 1094 .mode = 0644, 1095 .proc_handler = &proc_dointvec, 1096 }, 1097 { 1098 .ctl_name = FS_DENTRY, 1099 .procname = "dentry-state", 1100 .data = &dentry_stat, 1101 .maxlen = 6*sizeof(int), 1102 .mode = 0444, 1103 .proc_handler = &proc_dointvec, 1104 }, 1105 { 1106 .ctl_name = FS_OVERFLOWUID, 1107 .procname = "overflowuid", 1108 .data = &fs_overflowuid, 1109 .maxlen = sizeof(int), 1110 .mode = 0644, 1111 .proc_handler = &proc_dointvec_minmax, 1112 .strategy = &sysctl_intvec, 1113 .extra1 = &minolduid, 1114 .extra2 = &maxolduid, 1115 }, 1116 { 1117 .ctl_name = FS_OVERFLOWGID, 1118 .procname = "overflowgid", 1119 .data = &fs_overflowgid, 1120 .maxlen = sizeof(int), 1121 .mode = 0644, 1122 .proc_handler = &proc_dointvec_minmax, 1123 .strategy = &sysctl_intvec, 1124 .extra1 = &minolduid, 1125 .extra2 = &maxolduid, 1126 }, 1127 { 1128 .ctl_name = FS_LEASES, 1129 .procname = "leases-enable", 1130 .data = &leases_enable, 1131 .maxlen = sizeof(int), 1132 .mode = 0644, 1133 .proc_handler = &proc_dointvec, 1134 }, 1135 #ifdef CONFIG_DNOTIFY 1136 { 1137 .ctl_name = FS_DIR_NOTIFY, 1138 .procname = "dir-notify-enable", 1139 .data = &dir_notify_enable, 1140 .maxlen = sizeof(int), 1141 .mode = 0644, 1142 .proc_handler = &proc_dointvec, 1143 }, 1144 #endif 1145 #ifdef CONFIG_MMU 1146 { 1147 .ctl_name = FS_LEASE_TIME, 1148 .procname = "lease-break-time", 1149 .data = &lease_break_time, 1150 .maxlen = sizeof(int), 1151 .mode = 0644, 1152 .proc_handler = &proc_dointvec_minmax, 1153 .strategy = &sysctl_intvec, 1154 .extra1 = &zero, 1155 .extra2 = &two, 1156 }, 1157 { 1158 .ctl_name = FS_AIO_NR, 1159 .procname = "aio-nr", 1160 .data = &aio_nr, 1161 .maxlen = sizeof(aio_nr), 1162 .mode = 0444, 1163 .proc_handler = &proc_doulongvec_minmax, 1164 }, 1165 { 1166 .ctl_name = FS_AIO_MAX_NR, 1167 .procname = "aio-max-nr", 1168 .data = &aio_max_nr, 1169 .maxlen = sizeof(aio_max_nr), 1170 .mode = 0644, 1171 .proc_handler = &proc_doulongvec_minmax, 1172 }, 1173 #ifdef CONFIG_INOTIFY_USER 1174 { 1175 .ctl_name = FS_INOTIFY, 1176 .procname = "inotify", 1177 .mode = 0555, 1178 .child = inotify_table, 1179 }, 1180 #endif 1181 #endif 1182 { 1183 .ctl_name = KERN_SETUID_DUMPABLE, 1184 .procname = "suid_dumpable", 1185 .data = &suid_dumpable, 1186 .maxlen = sizeof(int), 1187 .mode = 0644, 1188 .proc_handler = &proc_dointvec, 1189 }, 1190 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE) 1191 { 1192 .ctl_name = CTL_UNNUMBERED, 1193 .procname = "binfmt_misc", 1194 .mode = 0555, 1195 .child = binfmt_misc_table, 1196 }, 1197 #endif 1198 /* 1199 * NOTE: do not add new entries to this table unless you have read 1200 * Documentation/sysctl/ctl_unnumbered.txt 1201 */ 1202 { .ctl_name = 0 } 1203 }; 1204 1205 static ctl_table debug_table[] = { 1206 #ifdef CONFIG_X86 1207 { 1208 .ctl_name = CTL_UNNUMBERED, 1209 .procname = "exception-trace", 1210 .data = &show_unhandled_signals, 1211 .maxlen = sizeof(int), 1212 .mode = 0644, 1213 .proc_handler = proc_dointvec 1214 }, 1215 #endif 1216 { .ctl_name = 0 } 1217 }; 1218 1219 static ctl_table dev_table[] = { 1220 { .ctl_name = 0 } 1221 }; 1222 1223 static DEFINE_SPINLOCK(sysctl_lock); 1224 1225 /* called under sysctl_lock */ 1226 static int use_table(struct ctl_table_header *p) 1227 { 1228 if (unlikely(p->unregistering)) 1229 return 0; 1230 p->used++; 1231 return 1; 1232 } 1233 1234 /* called under sysctl_lock */ 1235 static void unuse_table(struct ctl_table_header *p) 1236 { 1237 if (!--p->used) 1238 if (unlikely(p->unregistering)) 1239 complete(p->unregistering); 1240 } 1241 1242 /* called under sysctl_lock, will reacquire if has to wait */ 1243 static void start_unregistering(struct ctl_table_header *p) 1244 { 1245 /* 1246 * if p->used is 0, nobody will ever touch that entry again; 1247 * we'll eliminate all paths to it before dropping sysctl_lock 1248 */ 1249 if (unlikely(p->used)) { 1250 struct completion wait; 1251 init_completion(&wait); 1252 p->unregistering = &wait; 1253 spin_unlock(&sysctl_lock); 1254 wait_for_completion(&wait); 1255 spin_lock(&sysctl_lock); 1256 } 1257 /* 1258 * do not remove from the list until nobody holds it; walking the 1259 * list in do_sysctl() relies on that. 1260 */ 1261 list_del_init(&p->ctl_entry); 1262 } 1263 1264 void sysctl_head_finish(struct ctl_table_header *head) 1265 { 1266 if (!head) 1267 return; 1268 spin_lock(&sysctl_lock); 1269 unuse_table(head); 1270 spin_unlock(&sysctl_lock); 1271 } 1272 1273 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev) 1274 { 1275 struct ctl_table_header *head; 1276 struct list_head *tmp; 1277 spin_lock(&sysctl_lock); 1278 if (prev) { 1279 tmp = &prev->ctl_entry; 1280 unuse_table(prev); 1281 goto next; 1282 } 1283 tmp = &root_table_header.ctl_entry; 1284 for (;;) { 1285 head = list_entry(tmp, struct ctl_table_header, ctl_entry); 1286 1287 if (!use_table(head)) 1288 goto next; 1289 spin_unlock(&sysctl_lock); 1290 return head; 1291 next: 1292 tmp = tmp->next; 1293 if (tmp == &root_table_header.ctl_entry) 1294 break; 1295 } 1296 spin_unlock(&sysctl_lock); 1297 return NULL; 1298 } 1299 1300 #ifdef CONFIG_SYSCTL_SYSCALL 1301 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp, 1302 void __user *newval, size_t newlen) 1303 { 1304 struct ctl_table_header *head; 1305 int error = -ENOTDIR; 1306 1307 if (nlen <= 0 || nlen >= CTL_MAXNAME) 1308 return -ENOTDIR; 1309 if (oldval) { 1310 int old_len; 1311 if (!oldlenp || get_user(old_len, oldlenp)) 1312 return -EFAULT; 1313 } 1314 1315 for (head = sysctl_head_next(NULL); head; 1316 head = sysctl_head_next(head)) { 1317 error = parse_table(name, nlen, oldval, oldlenp, 1318 newval, newlen, head->ctl_table); 1319 if (error != -ENOTDIR) { 1320 sysctl_head_finish(head); 1321 break; 1322 } 1323 } 1324 return error; 1325 } 1326 1327 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 1328 { 1329 struct __sysctl_args tmp; 1330 int error; 1331 1332 if (copy_from_user(&tmp, args, sizeof(tmp))) 1333 return -EFAULT; 1334 1335 lock_kernel(); 1336 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp, 1337 tmp.newval, tmp.newlen); 1338 unlock_kernel(); 1339 return error; 1340 } 1341 #endif /* CONFIG_SYSCTL_SYSCALL */ 1342 1343 /* 1344 * sysctl_perm does NOT grant the superuser all rights automatically, because 1345 * some sysctl variables are readonly even to root. 1346 */ 1347 1348 static int test_perm(int mode, int op) 1349 { 1350 if (!current->euid) 1351 mode >>= 6; 1352 else if (in_egroup_p(0)) 1353 mode >>= 3; 1354 if ((mode & op & 0007) == op) 1355 return 0; 1356 return -EACCES; 1357 } 1358 1359 int sysctl_perm(ctl_table *table, int op) 1360 { 1361 int error; 1362 error = security_sysctl(table, op); 1363 if (error) 1364 return error; 1365 return test_perm(table->mode, op); 1366 } 1367 1368 #ifdef CONFIG_SYSCTL_SYSCALL 1369 static int parse_table(int __user *name, int nlen, 1370 void __user *oldval, size_t __user *oldlenp, 1371 void __user *newval, size_t newlen, 1372 ctl_table *table) 1373 { 1374 int n; 1375 repeat: 1376 if (!nlen) 1377 return -ENOTDIR; 1378 if (get_user(n, name)) 1379 return -EFAULT; 1380 for ( ; table->ctl_name || table->procname; table++) { 1381 if (!table->ctl_name) 1382 continue; 1383 if (n == table->ctl_name) { 1384 int error; 1385 if (table->child) { 1386 if (sysctl_perm(table, 001)) 1387 return -EPERM; 1388 name++; 1389 nlen--; 1390 table = table->child; 1391 goto repeat; 1392 } 1393 error = do_sysctl_strategy(table, name, nlen, 1394 oldval, oldlenp, 1395 newval, newlen); 1396 return error; 1397 } 1398 } 1399 return -ENOTDIR; 1400 } 1401 1402 /* Perform the actual read/write of a sysctl table entry. */ 1403 int do_sysctl_strategy (ctl_table *table, 1404 int __user *name, int nlen, 1405 void __user *oldval, size_t __user *oldlenp, 1406 void __user *newval, size_t newlen) 1407 { 1408 int op = 0, rc; 1409 size_t len; 1410 1411 if (oldval) 1412 op |= 004; 1413 if (newval) 1414 op |= 002; 1415 if (sysctl_perm(table, op)) 1416 return -EPERM; 1417 1418 if (table->strategy) { 1419 rc = table->strategy(table, name, nlen, oldval, oldlenp, 1420 newval, newlen); 1421 if (rc < 0) 1422 return rc; 1423 if (rc > 0) 1424 return 0; 1425 } 1426 1427 /* If there is no strategy routine, or if the strategy returns 1428 * zero, proceed with automatic r/w */ 1429 if (table->data && table->maxlen) { 1430 if (oldval && oldlenp) { 1431 if (get_user(len, oldlenp)) 1432 return -EFAULT; 1433 if (len) { 1434 if (len > table->maxlen) 1435 len = table->maxlen; 1436 if(copy_to_user(oldval, table->data, len)) 1437 return -EFAULT; 1438 if(put_user(len, oldlenp)) 1439 return -EFAULT; 1440 } 1441 } 1442 if (newval && newlen) { 1443 len = newlen; 1444 if (len > table->maxlen) 1445 len = table->maxlen; 1446 if(copy_from_user(table->data, newval, len)) 1447 return -EFAULT; 1448 } 1449 } 1450 return 0; 1451 } 1452 #endif /* CONFIG_SYSCTL_SYSCALL */ 1453 1454 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table) 1455 { 1456 for (; table->ctl_name || table->procname; table++) { 1457 table->parent = parent; 1458 if (table->child) 1459 sysctl_set_parent(table, table->child); 1460 } 1461 } 1462 1463 static __init int sysctl_init(void) 1464 { 1465 sysctl_set_parent(NULL, root_table); 1466 return 0; 1467 } 1468 1469 core_initcall(sysctl_init); 1470 1471 /** 1472 * register_sysctl_table - register a sysctl hierarchy 1473 * @table: the top-level table structure 1474 * 1475 * Register a sysctl table hierarchy. @table should be a filled in ctl_table 1476 * array. An entry with a ctl_name of 0 terminates the table. 1477 * 1478 * The members of the &ctl_table structure are used as follows: 1479 * 1480 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number 1481 * must be unique within that level of sysctl 1482 * 1483 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not 1484 * enter a sysctl file 1485 * 1486 * data - a pointer to data for use by proc_handler 1487 * 1488 * maxlen - the maximum size in bytes of the data 1489 * 1490 * mode - the file permissions for the /proc/sys file, and for sysctl(2) 1491 * 1492 * child - a pointer to the child sysctl table if this entry is a directory, or 1493 * %NULL. 1494 * 1495 * proc_handler - the text handler routine (described below) 1496 * 1497 * strategy - the strategy routine (described below) 1498 * 1499 * de - for internal use by the sysctl routines 1500 * 1501 * extra1, extra2 - extra pointers usable by the proc handler routines 1502 * 1503 * Leaf nodes in the sysctl tree will be represented by a single file 1504 * under /proc; non-leaf nodes will be represented by directories. 1505 * 1506 * sysctl(2) can automatically manage read and write requests through 1507 * the sysctl table. The data and maxlen fields of the ctl_table 1508 * struct enable minimal validation of the values being written to be 1509 * performed, and the mode field allows minimal authentication. 1510 * 1511 * More sophisticated management can be enabled by the provision of a 1512 * strategy routine with the table entry. This will be called before 1513 * any automatic read or write of the data is performed. 1514 * 1515 * The strategy routine may return 1516 * 1517 * < 0 - Error occurred (error is passed to user process) 1518 * 1519 * 0 - OK - proceed with automatic read or write. 1520 * 1521 * > 0 - OK - read or write has been done by the strategy routine, so 1522 * return immediately. 1523 * 1524 * There must be a proc_handler routine for any terminal nodes 1525 * mirrored under /proc/sys (non-terminals are handled by a built-in 1526 * directory handler). Several default handlers are available to 1527 * cover common cases - 1528 * 1529 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(), 1530 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 1531 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax() 1532 * 1533 * It is the handler's job to read the input buffer from user memory 1534 * and process it. The handler should return 0 on success. 1535 * 1536 * This routine returns %NULL on a failure to register, and a pointer 1537 * to the table header on success. 1538 */ 1539 struct ctl_table_header *register_sysctl_table(ctl_table * table) 1540 { 1541 struct ctl_table_header *tmp; 1542 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL); 1543 if (!tmp) 1544 return NULL; 1545 tmp->ctl_table = table; 1546 INIT_LIST_HEAD(&tmp->ctl_entry); 1547 tmp->used = 0; 1548 tmp->unregistering = NULL; 1549 sysctl_set_parent(NULL, table); 1550 spin_lock(&sysctl_lock); 1551 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry); 1552 spin_unlock(&sysctl_lock); 1553 return tmp; 1554 } 1555 1556 /** 1557 * unregister_sysctl_table - unregister a sysctl table hierarchy 1558 * @header: the header returned from register_sysctl_table 1559 * 1560 * Unregisters the sysctl table and all children. proc entries may not 1561 * actually be removed until they are no longer used by anyone. 1562 */ 1563 void unregister_sysctl_table(struct ctl_table_header * header) 1564 { 1565 might_sleep(); 1566 spin_lock(&sysctl_lock); 1567 start_unregistering(header); 1568 spin_unlock(&sysctl_lock); 1569 kfree(header); 1570 } 1571 1572 #else /* !CONFIG_SYSCTL */ 1573 struct ctl_table_header *register_sysctl_table(ctl_table * table) 1574 { 1575 return NULL; 1576 } 1577 1578 void unregister_sysctl_table(struct ctl_table_header * table) 1579 { 1580 } 1581 1582 #endif /* CONFIG_SYSCTL */ 1583 1584 /* 1585 * /proc/sys support 1586 */ 1587 1588 #ifdef CONFIG_PROC_SYSCTL 1589 1590 static int _proc_do_string(void* data, int maxlen, int write, 1591 struct file *filp, void __user *buffer, 1592 size_t *lenp, loff_t *ppos) 1593 { 1594 size_t len; 1595 char __user *p; 1596 char c; 1597 1598 if (!data || !maxlen || !*lenp) { 1599 *lenp = 0; 1600 return 0; 1601 } 1602 1603 if (write) { 1604 len = 0; 1605 p = buffer; 1606 while (len < *lenp) { 1607 if (get_user(c, p++)) 1608 return -EFAULT; 1609 if (c == 0 || c == '\n') 1610 break; 1611 len++; 1612 } 1613 if (len >= maxlen) 1614 len = maxlen-1; 1615 if(copy_from_user(data, buffer, len)) 1616 return -EFAULT; 1617 ((char *) data)[len] = 0; 1618 *ppos += *lenp; 1619 } else { 1620 len = strlen(data); 1621 if (len > maxlen) 1622 len = maxlen; 1623 1624 if (*ppos > len) { 1625 *lenp = 0; 1626 return 0; 1627 } 1628 1629 data += *ppos; 1630 len -= *ppos; 1631 1632 if (len > *lenp) 1633 len = *lenp; 1634 if (len) 1635 if(copy_to_user(buffer, data, len)) 1636 return -EFAULT; 1637 if (len < *lenp) { 1638 if(put_user('\n', ((char __user *) buffer) + len)) 1639 return -EFAULT; 1640 len++; 1641 } 1642 *lenp = len; 1643 *ppos += len; 1644 } 1645 return 0; 1646 } 1647 1648 /** 1649 * proc_dostring - read a string sysctl 1650 * @table: the sysctl table 1651 * @write: %TRUE if this is a write to the sysctl file 1652 * @filp: the file structure 1653 * @buffer: the user buffer 1654 * @lenp: the size of the user buffer 1655 * @ppos: file position 1656 * 1657 * Reads/writes a string from/to the user buffer. If the kernel 1658 * buffer provided is not large enough to hold the string, the 1659 * string is truncated. The copied string is %NULL-terminated. 1660 * If the string is being read by the user process, it is copied 1661 * and a newline '\n' is added. It is truncated if the buffer is 1662 * not large enough. 1663 * 1664 * Returns 0 on success. 1665 */ 1666 int proc_dostring(ctl_table *table, int write, struct file *filp, 1667 void __user *buffer, size_t *lenp, loff_t *ppos) 1668 { 1669 return _proc_do_string(table->data, table->maxlen, write, filp, 1670 buffer, lenp, ppos); 1671 } 1672 1673 1674 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp, 1675 int *valp, 1676 int write, void *data) 1677 { 1678 if (write) { 1679 *valp = *negp ? -*lvalp : *lvalp; 1680 } else { 1681 int val = *valp; 1682 if (val < 0) { 1683 *negp = -1; 1684 *lvalp = (unsigned long)-val; 1685 } else { 1686 *negp = 0; 1687 *lvalp = (unsigned long)val; 1688 } 1689 } 1690 return 0; 1691 } 1692 1693 static int __do_proc_dointvec(void *tbl_data, ctl_table *table, 1694 int write, struct file *filp, void __user *buffer, 1695 size_t *lenp, loff_t *ppos, 1696 int (*conv)(int *negp, unsigned long *lvalp, int *valp, 1697 int write, void *data), 1698 void *data) 1699 { 1700 #define TMPBUFLEN 21 1701 int *i, vleft, first=1, neg, val; 1702 unsigned long lval; 1703 size_t left, len; 1704 1705 char buf[TMPBUFLEN], *p; 1706 char __user *s = buffer; 1707 1708 if (!tbl_data || !table->maxlen || !*lenp || 1709 (*ppos && !write)) { 1710 *lenp = 0; 1711 return 0; 1712 } 1713 1714 i = (int *) tbl_data; 1715 vleft = table->maxlen / sizeof(*i); 1716 left = *lenp; 1717 1718 if (!conv) 1719 conv = do_proc_dointvec_conv; 1720 1721 for (; left && vleft--; i++, first=0) { 1722 if (write) { 1723 while (left) { 1724 char c; 1725 if (get_user(c, s)) 1726 return -EFAULT; 1727 if (!isspace(c)) 1728 break; 1729 left--; 1730 s++; 1731 } 1732 if (!left) 1733 break; 1734 neg = 0; 1735 len = left; 1736 if (len > sizeof(buf) - 1) 1737 len = sizeof(buf) - 1; 1738 if (copy_from_user(buf, s, len)) 1739 return -EFAULT; 1740 buf[len] = 0; 1741 p = buf; 1742 if (*p == '-' && left > 1) { 1743 neg = 1; 1744 p++; 1745 } 1746 if (*p < '0' || *p > '9') 1747 break; 1748 1749 lval = simple_strtoul(p, &p, 0); 1750 1751 len = p-buf; 1752 if ((len < left) && *p && !isspace(*p)) 1753 break; 1754 if (neg) 1755 val = -val; 1756 s += len; 1757 left -= len; 1758 1759 if (conv(&neg, &lval, i, 1, data)) 1760 break; 1761 } else { 1762 p = buf; 1763 if (!first) 1764 *p++ = '\t'; 1765 1766 if (conv(&neg, &lval, i, 0, data)) 1767 break; 1768 1769 sprintf(p, "%s%lu", neg ? "-" : "", lval); 1770 len = strlen(buf); 1771 if (len > left) 1772 len = left; 1773 if(copy_to_user(s, buf, len)) 1774 return -EFAULT; 1775 left -= len; 1776 s += len; 1777 } 1778 } 1779 1780 if (!write && !first && left) { 1781 if(put_user('\n', s)) 1782 return -EFAULT; 1783 left--, s++; 1784 } 1785 if (write) { 1786 while (left) { 1787 char c; 1788 if (get_user(c, s++)) 1789 return -EFAULT; 1790 if (!isspace(c)) 1791 break; 1792 left--; 1793 } 1794 } 1795 if (write && first) 1796 return -EINVAL; 1797 *lenp -= left; 1798 *ppos += *lenp; 1799 return 0; 1800 #undef TMPBUFLEN 1801 } 1802 1803 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp, 1804 void __user *buffer, size_t *lenp, loff_t *ppos, 1805 int (*conv)(int *negp, unsigned long *lvalp, int *valp, 1806 int write, void *data), 1807 void *data) 1808 { 1809 return __do_proc_dointvec(table->data, table, write, filp, 1810 buffer, lenp, ppos, conv, data); 1811 } 1812 1813 /** 1814 * proc_dointvec - read a vector of integers 1815 * @table: the sysctl table 1816 * @write: %TRUE if this is a write to the sysctl file 1817 * @filp: the file structure 1818 * @buffer: the user buffer 1819 * @lenp: the size of the user buffer 1820 * @ppos: file position 1821 * 1822 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 1823 * values from/to the user buffer, treated as an ASCII string. 1824 * 1825 * Returns 0 on success. 1826 */ 1827 int proc_dointvec(ctl_table *table, int write, struct file *filp, 1828 void __user *buffer, size_t *lenp, loff_t *ppos) 1829 { 1830 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1831 NULL,NULL); 1832 } 1833 1834 #define OP_SET 0 1835 #define OP_AND 1 1836 #define OP_OR 2 1837 1838 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp, 1839 int *valp, 1840 int write, void *data) 1841 { 1842 int op = *(int *)data; 1843 if (write) { 1844 int val = *negp ? -*lvalp : *lvalp; 1845 switch(op) { 1846 case OP_SET: *valp = val; break; 1847 case OP_AND: *valp &= val; break; 1848 case OP_OR: *valp |= val; break; 1849 } 1850 } else { 1851 int val = *valp; 1852 if (val < 0) { 1853 *negp = -1; 1854 *lvalp = (unsigned long)-val; 1855 } else { 1856 *negp = 0; 1857 *lvalp = (unsigned long)val; 1858 } 1859 } 1860 return 0; 1861 } 1862 1863 /* 1864 * init may raise the set. 1865 */ 1866 1867 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 1868 void __user *buffer, size_t *lenp, loff_t *ppos) 1869 { 1870 int op; 1871 1872 if (write && !capable(CAP_SYS_MODULE)) { 1873 return -EPERM; 1874 } 1875 1876 op = is_init(current) ? OP_SET : OP_AND; 1877 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1878 do_proc_dointvec_bset_conv,&op); 1879 } 1880 1881 /* 1882 * Taint values can only be increased 1883 */ 1884 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp, 1885 void __user *buffer, size_t *lenp, loff_t *ppos) 1886 { 1887 int op; 1888 1889 if (write && !capable(CAP_SYS_ADMIN)) 1890 return -EPERM; 1891 1892 op = OP_OR; 1893 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 1894 do_proc_dointvec_bset_conv,&op); 1895 } 1896 1897 struct do_proc_dointvec_minmax_conv_param { 1898 int *min; 1899 int *max; 1900 }; 1901 1902 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 1903 int *valp, 1904 int write, void *data) 1905 { 1906 struct do_proc_dointvec_minmax_conv_param *param = data; 1907 if (write) { 1908 int val = *negp ? -*lvalp : *lvalp; 1909 if ((param->min && *param->min > val) || 1910 (param->max && *param->max < val)) 1911 return -EINVAL; 1912 *valp = val; 1913 } else { 1914 int val = *valp; 1915 if (val < 0) { 1916 *negp = -1; 1917 *lvalp = (unsigned long)-val; 1918 } else { 1919 *negp = 0; 1920 *lvalp = (unsigned long)val; 1921 } 1922 } 1923 return 0; 1924 } 1925 1926 /** 1927 * proc_dointvec_minmax - read a vector of integers with min/max values 1928 * @table: the sysctl table 1929 * @write: %TRUE if this is a write to the sysctl file 1930 * @filp: the file structure 1931 * @buffer: the user buffer 1932 * @lenp: the size of the user buffer 1933 * @ppos: file position 1934 * 1935 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 1936 * values from/to the user buffer, treated as an ASCII string. 1937 * 1938 * This routine will ensure the values are within the range specified by 1939 * table->extra1 (min) and table->extra2 (max). 1940 * 1941 * Returns 0 on success. 1942 */ 1943 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 1944 void __user *buffer, size_t *lenp, loff_t *ppos) 1945 { 1946 struct do_proc_dointvec_minmax_conv_param param = { 1947 .min = (int *) table->extra1, 1948 .max = (int *) table->extra2, 1949 }; 1950 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 1951 do_proc_dointvec_minmax_conv, ¶m); 1952 } 1953 1954 static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write, 1955 struct file *filp, 1956 void __user *buffer, 1957 size_t *lenp, loff_t *ppos, 1958 unsigned long convmul, 1959 unsigned long convdiv) 1960 { 1961 #define TMPBUFLEN 21 1962 unsigned long *i, *min, *max, val; 1963 int vleft, first=1, neg; 1964 size_t len, left; 1965 char buf[TMPBUFLEN], *p; 1966 char __user *s = buffer; 1967 1968 if (!data || !table->maxlen || !*lenp || 1969 (*ppos && !write)) { 1970 *lenp = 0; 1971 return 0; 1972 } 1973 1974 i = (unsigned long *) data; 1975 min = (unsigned long *) table->extra1; 1976 max = (unsigned long *) table->extra2; 1977 vleft = table->maxlen / sizeof(unsigned long); 1978 left = *lenp; 1979 1980 for (; left && vleft--; i++, min++, max++, first=0) { 1981 if (write) { 1982 while (left) { 1983 char c; 1984 if (get_user(c, s)) 1985 return -EFAULT; 1986 if (!isspace(c)) 1987 break; 1988 left--; 1989 s++; 1990 } 1991 if (!left) 1992 break; 1993 neg = 0; 1994 len = left; 1995 if (len > TMPBUFLEN-1) 1996 len = TMPBUFLEN-1; 1997 if (copy_from_user(buf, s, len)) 1998 return -EFAULT; 1999 buf[len] = 0; 2000 p = buf; 2001 if (*p == '-' && left > 1) { 2002 neg = 1; 2003 p++; 2004 } 2005 if (*p < '0' || *p > '9') 2006 break; 2007 val = simple_strtoul(p, &p, 0) * convmul / convdiv ; 2008 len = p-buf; 2009 if ((len < left) && *p && !isspace(*p)) 2010 break; 2011 if (neg) 2012 val = -val; 2013 s += len; 2014 left -= len; 2015 2016 if(neg) 2017 continue; 2018 if ((min && val < *min) || (max && val > *max)) 2019 continue; 2020 *i = val; 2021 } else { 2022 p = buf; 2023 if (!first) 2024 *p++ = '\t'; 2025 sprintf(p, "%lu", convdiv * (*i) / convmul); 2026 len = strlen(buf); 2027 if (len > left) 2028 len = left; 2029 if(copy_to_user(s, buf, len)) 2030 return -EFAULT; 2031 left -= len; 2032 s += len; 2033 } 2034 } 2035 2036 if (!write && !first && left) { 2037 if(put_user('\n', s)) 2038 return -EFAULT; 2039 left--, s++; 2040 } 2041 if (write) { 2042 while (left) { 2043 char c; 2044 if (get_user(c, s++)) 2045 return -EFAULT; 2046 if (!isspace(c)) 2047 break; 2048 left--; 2049 } 2050 } 2051 if (write && first) 2052 return -EINVAL; 2053 *lenp -= left; 2054 *ppos += *lenp; 2055 return 0; 2056 #undef TMPBUFLEN 2057 } 2058 2059 static int do_proc_doulongvec_minmax(ctl_table *table, int write, 2060 struct file *filp, 2061 void __user *buffer, 2062 size_t *lenp, loff_t *ppos, 2063 unsigned long convmul, 2064 unsigned long convdiv) 2065 { 2066 return __do_proc_doulongvec_minmax(table->data, table, write, 2067 filp, buffer, lenp, ppos, convmul, convdiv); 2068 } 2069 2070 /** 2071 * proc_doulongvec_minmax - read a vector of long integers with min/max values 2072 * @table: the sysctl table 2073 * @write: %TRUE if this is a write to the sysctl file 2074 * @filp: the file structure 2075 * @buffer: the user buffer 2076 * @lenp: the size of the user buffer 2077 * @ppos: file position 2078 * 2079 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 2080 * values from/to the user buffer, treated as an ASCII string. 2081 * 2082 * This routine will ensure the values are within the range specified by 2083 * table->extra1 (min) and table->extra2 (max). 2084 * 2085 * Returns 0 on success. 2086 */ 2087 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 2088 void __user *buffer, size_t *lenp, loff_t *ppos) 2089 { 2090 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l); 2091 } 2092 2093 /** 2094 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values 2095 * @table: the sysctl table 2096 * @write: %TRUE if this is a write to the sysctl file 2097 * @filp: the file structure 2098 * @buffer: the user buffer 2099 * @lenp: the size of the user buffer 2100 * @ppos: file position 2101 * 2102 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long 2103 * values from/to the user buffer, treated as an ASCII string. The values 2104 * are treated as milliseconds, and converted to jiffies when they are stored. 2105 * 2106 * This routine will ensure the values are within the range specified by 2107 * table->extra1 (min) and table->extra2 (max). 2108 * 2109 * Returns 0 on success. 2110 */ 2111 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 2112 struct file *filp, 2113 void __user *buffer, 2114 size_t *lenp, loff_t *ppos) 2115 { 2116 return do_proc_doulongvec_minmax(table, write, filp, buffer, 2117 lenp, ppos, HZ, 1000l); 2118 } 2119 2120 2121 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp, 2122 int *valp, 2123 int write, void *data) 2124 { 2125 if (write) { 2126 if (*lvalp > LONG_MAX / HZ) 2127 return 1; 2128 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ); 2129 } else { 2130 int val = *valp; 2131 unsigned long lval; 2132 if (val < 0) { 2133 *negp = -1; 2134 lval = (unsigned long)-val; 2135 } else { 2136 *negp = 0; 2137 lval = (unsigned long)val; 2138 } 2139 *lvalp = lval / HZ; 2140 } 2141 return 0; 2142 } 2143 2144 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp, 2145 int *valp, 2146 int write, void *data) 2147 { 2148 if (write) { 2149 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ) 2150 return 1; 2151 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp); 2152 } else { 2153 int val = *valp; 2154 unsigned long lval; 2155 if (val < 0) { 2156 *negp = -1; 2157 lval = (unsigned long)-val; 2158 } else { 2159 *negp = 0; 2160 lval = (unsigned long)val; 2161 } 2162 *lvalp = jiffies_to_clock_t(lval); 2163 } 2164 return 0; 2165 } 2166 2167 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp, 2168 int *valp, 2169 int write, void *data) 2170 { 2171 if (write) { 2172 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp); 2173 } else { 2174 int val = *valp; 2175 unsigned long lval; 2176 if (val < 0) { 2177 *negp = -1; 2178 lval = (unsigned long)-val; 2179 } else { 2180 *negp = 0; 2181 lval = (unsigned long)val; 2182 } 2183 *lvalp = jiffies_to_msecs(lval); 2184 } 2185 return 0; 2186 } 2187 2188 /** 2189 * proc_dointvec_jiffies - read a vector of integers as seconds 2190 * @table: the sysctl table 2191 * @write: %TRUE if this is a write to the sysctl file 2192 * @filp: the file structure 2193 * @buffer: the user buffer 2194 * @lenp: the size of the user buffer 2195 * @ppos: file position 2196 * 2197 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2198 * values from/to the user buffer, treated as an ASCII string. 2199 * The values read are assumed to be in seconds, and are converted into 2200 * jiffies. 2201 * 2202 * Returns 0 on success. 2203 */ 2204 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2205 void __user *buffer, size_t *lenp, loff_t *ppos) 2206 { 2207 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2208 do_proc_dointvec_jiffies_conv,NULL); 2209 } 2210 2211 /** 2212 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds 2213 * @table: the sysctl table 2214 * @write: %TRUE if this is a write to the sysctl file 2215 * @filp: the file structure 2216 * @buffer: the user buffer 2217 * @lenp: the size of the user buffer 2218 * @ppos: pointer to the file position 2219 * 2220 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2221 * values from/to the user buffer, treated as an ASCII string. 2222 * The values read are assumed to be in 1/USER_HZ seconds, and 2223 * are converted into jiffies. 2224 * 2225 * Returns 0 on success. 2226 */ 2227 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2228 void __user *buffer, size_t *lenp, loff_t *ppos) 2229 { 2230 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos, 2231 do_proc_dointvec_userhz_jiffies_conv,NULL); 2232 } 2233 2234 /** 2235 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds 2236 * @table: the sysctl table 2237 * @write: %TRUE if this is a write to the sysctl file 2238 * @filp: the file structure 2239 * @buffer: the user buffer 2240 * @lenp: the size of the user buffer 2241 * @ppos: file position 2242 * @ppos: the current position in the file 2243 * 2244 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer 2245 * values from/to the user buffer, treated as an ASCII string. 2246 * The values read are assumed to be in 1/1000 seconds, and 2247 * are converted into jiffies. 2248 * 2249 * Returns 0 on success. 2250 */ 2251 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2252 void __user *buffer, size_t *lenp, loff_t *ppos) 2253 { 2254 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos, 2255 do_proc_dointvec_ms_jiffies_conv, NULL); 2256 } 2257 2258 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp, 2259 void __user *buffer, size_t *lenp, loff_t *ppos) 2260 { 2261 struct pid *new_pid; 2262 pid_t tmp; 2263 int r; 2264 2265 tmp = pid_nr(cad_pid); 2266 2267 r = __do_proc_dointvec(&tmp, table, write, filp, buffer, 2268 lenp, ppos, NULL, NULL); 2269 if (r || !write) 2270 return r; 2271 2272 new_pid = find_get_pid(tmp); 2273 if (!new_pid) 2274 return -ESRCH; 2275 2276 put_pid(xchg(&cad_pid, new_pid)); 2277 return 0; 2278 } 2279 2280 #else /* CONFIG_PROC_FS */ 2281 2282 int proc_dostring(ctl_table *table, int write, struct file *filp, 2283 void __user *buffer, size_t *lenp, loff_t *ppos) 2284 { 2285 return -ENOSYS; 2286 } 2287 2288 int proc_dointvec(ctl_table *table, int write, struct file *filp, 2289 void __user *buffer, size_t *lenp, loff_t *ppos) 2290 { 2291 return -ENOSYS; 2292 } 2293 2294 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp, 2295 void __user *buffer, size_t *lenp, loff_t *ppos) 2296 { 2297 return -ENOSYS; 2298 } 2299 2300 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp, 2301 void __user *buffer, size_t *lenp, loff_t *ppos) 2302 { 2303 return -ENOSYS; 2304 } 2305 2306 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp, 2307 void __user *buffer, size_t *lenp, loff_t *ppos) 2308 { 2309 return -ENOSYS; 2310 } 2311 2312 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp, 2313 void __user *buffer, size_t *lenp, loff_t *ppos) 2314 { 2315 return -ENOSYS; 2316 } 2317 2318 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp, 2319 void __user *buffer, size_t *lenp, loff_t *ppos) 2320 { 2321 return -ENOSYS; 2322 } 2323 2324 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp, 2325 void __user *buffer, size_t *lenp, loff_t *ppos) 2326 { 2327 return -ENOSYS; 2328 } 2329 2330 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write, 2331 struct file *filp, 2332 void __user *buffer, 2333 size_t *lenp, loff_t *ppos) 2334 { 2335 return -ENOSYS; 2336 } 2337 2338 2339 #endif /* CONFIG_PROC_FS */ 2340 2341 2342 #ifdef CONFIG_SYSCTL_SYSCALL 2343 /* 2344 * General sysctl support routines 2345 */ 2346 2347 /* The generic string strategy routine: */ 2348 int sysctl_string(ctl_table *table, int __user *name, int nlen, 2349 void __user *oldval, size_t __user *oldlenp, 2350 void __user *newval, size_t newlen) 2351 { 2352 if (!table->data || !table->maxlen) 2353 return -ENOTDIR; 2354 2355 if (oldval && oldlenp) { 2356 size_t bufsize; 2357 if (get_user(bufsize, oldlenp)) 2358 return -EFAULT; 2359 if (bufsize) { 2360 size_t len = strlen(table->data), copied; 2361 2362 /* This shouldn't trigger for a well-formed sysctl */ 2363 if (len > table->maxlen) 2364 len = table->maxlen; 2365 2366 /* Copy up to a max of bufsize-1 bytes of the string */ 2367 copied = (len >= bufsize) ? bufsize - 1 : len; 2368 2369 if (copy_to_user(oldval, table->data, copied) || 2370 put_user(0, (char __user *)(oldval + copied))) 2371 return -EFAULT; 2372 if (put_user(len, oldlenp)) 2373 return -EFAULT; 2374 } 2375 } 2376 if (newval && newlen) { 2377 size_t len = newlen; 2378 if (len > table->maxlen) 2379 len = table->maxlen; 2380 if(copy_from_user(table->data, newval, len)) 2381 return -EFAULT; 2382 if (len == table->maxlen) 2383 len--; 2384 ((char *) table->data)[len] = 0; 2385 } 2386 return 1; 2387 } 2388 2389 /* 2390 * This function makes sure that all of the integers in the vector 2391 * are between the minimum and maximum values given in the arrays 2392 * table->extra1 and table->extra2, respectively. 2393 */ 2394 int sysctl_intvec(ctl_table *table, int __user *name, int nlen, 2395 void __user *oldval, size_t __user *oldlenp, 2396 void __user *newval, size_t newlen) 2397 { 2398 2399 if (newval && newlen) { 2400 int __user *vec = (int __user *) newval; 2401 int *min = (int *) table->extra1; 2402 int *max = (int *) table->extra2; 2403 size_t length; 2404 int i; 2405 2406 if (newlen % sizeof(int) != 0) 2407 return -EINVAL; 2408 2409 if (!table->extra1 && !table->extra2) 2410 return 0; 2411 2412 if (newlen > table->maxlen) 2413 newlen = table->maxlen; 2414 length = newlen / sizeof(int); 2415 2416 for (i = 0; i < length; i++) { 2417 int value; 2418 if (get_user(value, vec + i)) 2419 return -EFAULT; 2420 if (min && value < min[i]) 2421 return -EINVAL; 2422 if (max && value > max[i]) 2423 return -EINVAL; 2424 } 2425 } 2426 return 0; 2427 } 2428 2429 /* Strategy function to convert jiffies to seconds */ 2430 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen, 2431 void __user *oldval, size_t __user *oldlenp, 2432 void __user *newval, size_t newlen) 2433 { 2434 if (oldval && oldlenp) { 2435 size_t olen; 2436 2437 if (get_user(olen, oldlenp)) 2438 return -EFAULT; 2439 if (olen) { 2440 int val; 2441 2442 if (olen < sizeof(int)) 2443 return -EINVAL; 2444 2445 val = *(int *)(table->data) / HZ; 2446 if (put_user(val, (int __user *)oldval)) 2447 return -EFAULT; 2448 if (put_user(sizeof(int), oldlenp)) 2449 return -EFAULT; 2450 } 2451 } 2452 if (newval && newlen) { 2453 int new; 2454 if (newlen != sizeof(int)) 2455 return -EINVAL; 2456 if (get_user(new, (int __user *)newval)) 2457 return -EFAULT; 2458 *(int *)(table->data) = new*HZ; 2459 } 2460 return 1; 2461 } 2462 2463 /* Strategy function to convert jiffies to seconds */ 2464 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, 2465 void __user *oldval, size_t __user *oldlenp, 2466 void __user *newval, size_t newlen) 2467 { 2468 if (oldval && oldlenp) { 2469 size_t olen; 2470 2471 if (get_user(olen, oldlenp)) 2472 return -EFAULT; 2473 if (olen) { 2474 int val; 2475 2476 if (olen < sizeof(int)) 2477 return -EINVAL; 2478 2479 val = jiffies_to_msecs(*(int *)(table->data)); 2480 if (put_user(val, (int __user *)oldval)) 2481 return -EFAULT; 2482 if (put_user(sizeof(int), oldlenp)) 2483 return -EFAULT; 2484 } 2485 } 2486 if (newval && newlen) { 2487 int new; 2488 if (newlen != sizeof(int)) 2489 return -EINVAL; 2490 if (get_user(new, (int __user *)newval)) 2491 return -EFAULT; 2492 *(int *)(table->data) = msecs_to_jiffies(new); 2493 } 2494 return 1; 2495 } 2496 2497 2498 2499 #else /* CONFIG_SYSCTL_SYSCALL */ 2500 2501 2502 asmlinkage long sys_sysctl(struct __sysctl_args __user *args) 2503 { 2504 static int msg_count; 2505 struct __sysctl_args tmp; 2506 int name[CTL_MAXNAME]; 2507 int i; 2508 2509 /* Read in the sysctl name for better debug message logging */ 2510 if (copy_from_user(&tmp, args, sizeof(tmp))) 2511 return -EFAULT; 2512 if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME) 2513 return -ENOTDIR; 2514 for (i = 0; i < tmp.nlen; i++) 2515 if (get_user(name[i], tmp.name + i)) 2516 return -EFAULT; 2517 2518 /* Ignore accesses to kernel.version */ 2519 if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION)) 2520 goto out; 2521 2522 if (msg_count < 5) { 2523 msg_count++; 2524 printk(KERN_INFO 2525 "warning: process `%s' used the removed sysctl " 2526 "system call with ", current->comm); 2527 for (i = 0; i < tmp.nlen; i++) 2528 printk("%d.", name[i]); 2529 printk("\n"); 2530 } 2531 out: 2532 return -ENOSYS; 2533 } 2534 2535 int sysctl_string(ctl_table *table, int __user *name, int nlen, 2536 void __user *oldval, size_t __user *oldlenp, 2537 void __user *newval, size_t newlen) 2538 { 2539 return -ENOSYS; 2540 } 2541 2542 int sysctl_intvec(ctl_table *table, int __user *name, int nlen, 2543 void __user *oldval, size_t __user *oldlenp, 2544 void __user *newval, size_t newlen) 2545 { 2546 return -ENOSYS; 2547 } 2548 2549 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen, 2550 void __user *oldval, size_t __user *oldlenp, 2551 void __user *newval, size_t newlen) 2552 { 2553 return -ENOSYS; 2554 } 2555 2556 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen, 2557 void __user *oldval, size_t __user *oldlenp, 2558 void __user *newval, size_t newlen) 2559 { 2560 return -ENOSYS; 2561 } 2562 2563 #endif /* CONFIG_SYSCTL_SYSCALL */ 2564 2565 /* 2566 * No sense putting this after each symbol definition, twice, 2567 * exception granted :-) 2568 */ 2569 EXPORT_SYMBOL(proc_dointvec); 2570 EXPORT_SYMBOL(proc_dointvec_jiffies); 2571 EXPORT_SYMBOL(proc_dointvec_minmax); 2572 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies); 2573 EXPORT_SYMBOL(proc_dointvec_ms_jiffies); 2574 EXPORT_SYMBOL(proc_dostring); 2575 EXPORT_SYMBOL(proc_doulongvec_minmax); 2576 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax); 2577 EXPORT_SYMBOL(register_sysctl_table); 2578 EXPORT_SYMBOL(sysctl_intvec); 2579 EXPORT_SYMBOL(sysctl_jiffies); 2580 EXPORT_SYMBOL(sysctl_ms_jiffies); 2581 EXPORT_SYMBOL(sysctl_string); 2582 EXPORT_SYMBOL(unregister_sysctl_table); 2583