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