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vmstat: use our own timer events
[linux-2.6-block.git] / kernel / sysctl.c
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1da177e4
LT		 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
1da177e4
LT		 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>
c59ede7b 27#include <linux/capability.h>
1da177e4
LT		 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>
0296b228 34#include <linux/kobject.h>
20380731 35#include <linux/net.h>
1da177e4
LT		 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>
c255d844
PM		 46#include <linux/nfs_fs.h>
47#include <linux/acpi.h>
1da177e4
LT		 48
49#include <asm/uaccess.h>
50#include <asm/processor.h>
51
529bf6be
DS		 52extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
53 void __user *buffer, size_t *lenp, loff_t *ppos);
54
29cbc78b
AK		 55#ifdef CONFIG_X86
56#include <asm/nmi.h>
0741f4d2 57#include <asm/stacktrace.h>
29cbc78b
AK		 58#endif
59
1da177e4
LT		 60#if defined(CONFIG_SYSCTL)
61
62/* External variables not in a header file. */
63extern int C_A_D;
64extern int sysctl_overcommit_memory;
65extern int sysctl_overcommit_ratio;
fadd8fbd 66extern int sysctl_panic_on_oom;
1da177e4 67extern int max_threads;
1da177e4 68extern int core_uses_pid;
d6e71144 69extern int suid_dumpable;
1da177e4 70extern char core_pattern[];
1da177e4
LT		 71extern int pid_max;
72extern int min_free_kbytes;
73extern int printk_ratelimit_jiffies;
74extern int printk_ratelimit_burst;
75extern int pid_max_min, pid_max_max;
9d0243bc 76extern int sysctl_drop_caches;
8ad4b1fb 77extern int percpu_pagelist_fraction;
bebfa101 78extern int compat_log;
5096add8 79extern int maps_protect;
1da177e4 80
1da177e4
LT		 81/* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
82static int maxolduid = 65535;
83static int minolduid;
8ad4b1fb 84static int min_percpu_pagelist_fract = 8;
1da177e4
LT		 85
86static int ngroups_max = NGROUPS_MAX;
87
88#ifdef CONFIG_KMOD
89extern char modprobe_path[];
90#endif
1da177e4
LT		 91#ifdef CONFIG_CHR_DEV_SG
92extern int sg_big_buff;
93#endif
1da177e4
LT		 94
95#ifdef __sparc__
96extern char reboot_command [];
97extern int stop_a_enabled;
98extern int scons_pwroff;
99#endif
100
101#ifdef __hppa__
102extern int pwrsw_enabled;
103extern int unaligned_enabled;
104#endif
105
347a8dc3 106#ifdef CONFIG_S390
1da177e4
LT		 107#ifdef CONFIG_MATHEMU
108extern int sysctl_ieee_emulation_warnings;
109#endif
110extern int sysctl_userprocess_debug;
951f22d5 111extern int spin_retry;
1da177e4
LT		 112#endif
113
114extern int sysctl_hz_timer;
115
116#ifdef CONFIG_BSD_PROCESS_ACCT
117extern int acct_parm[];
118#endif
119
d2b176ed
JS		 120#ifdef CONFIG_IA64
121extern int no_unaligned_warning;
122#endif
123
23f78d4a
IM		 124#ifdef CONFIG_RT_MUTEXES
125extern int max_lock_depth;
126#endif
127
b89a8171
EB		 128#ifdef CONFIG_SYSCTL_SYSCALL
129static int parse_table(int __user *, int, void __user *, size_t __user *,
1f29bcd7 130 void __user *, size_t, ctl_table *);
b89a8171
EB		 131#endif
132
6b49a257 133
d6f8ff73 134#ifdef CONFIG_PROC_SYSCTL
9ec52099
CLG		 135static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
136 void __user *buffer, size_t *lenp, loff_t *ppos);
34f5a398
TT		 137static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
138 void __user *buffer, size_t *lenp, loff_t *ppos);
d6f8ff73 139#endif
9ec52099 140
1da177e4
LT		 141static ctl_table root_table[];
142static struct ctl_table_header root_table_header =
143 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
144
145static ctl_table kern_table[];
146static ctl_table vm_table[];
1da177e4
LT		 147static ctl_table fs_table[];
148static ctl_table debug_table[];
149static ctl_table dev_table[];
150extern ctl_table random_table[];
151#ifdef CONFIG_UNIX98_PTYS
152extern ctl_table pty_table[];
153#endif
2d9048e2 154#ifdef CONFIG_INOTIFY_USER
0399cb08
RL		 155extern ctl_table inotify_table[];
156#endif
1da177e4
LT		 157
158#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
159int sysctl_legacy_va_layout;
160#endif
161
9bc9a6bd 162
1da177e4
LT		 163/* The default sysctl tables: */
164
165static ctl_table root_table[] = {
166 {
167 .ctl_name = CTL_KERN,
168 .procname = "kernel",
169 .mode = 0555,
170 .child = kern_table,
171 },
172 {
173 .ctl_name = CTL_VM,
174 .procname = "vm",
175 .mode = 0555,
176 .child = vm_table,
177 },
178#ifdef CONFIG_NET
179 {
180 .ctl_name = CTL_NET,
181 .procname = "net",
182 .mode = 0555,
183 .child = net_table,
184 },
185#endif
1da177e4
LT		 186 {
187 .ctl_name = CTL_FS,
188 .procname = "fs",
189 .mode = 0555,
190 .child = fs_table,
191 },
192 {
193 .ctl_name = CTL_DEBUG,
194 .procname = "debug",
195 .mode = 0555,
196 .child = debug_table,
197 },
198 {
199 .ctl_name = CTL_DEV,
200 .procname = "dev",
201 .mode = 0555,
202 .child = dev_table,
203 },
0eeca283 204
1da177e4
LT		 205 { .ctl_name = 0 }
206};
207
208static ctl_table kern_table[] = {
1da177e4
LT		 209 {
210 .ctl_name = KERN_PANIC,
211 .procname = "panic",
212 .data = &panic_timeout,
213 .maxlen = sizeof(int),
214 .mode = 0644,
215 .proc_handler = &proc_dointvec,
216 },
217 {
218 .ctl_name = KERN_CORE_USES_PID,
219 .procname = "core_uses_pid",
220 .data = &core_uses_pid,
221 .maxlen = sizeof(int),
222 .mode = 0644,
223 .proc_handler = &proc_dointvec,
224 },
225 {
226 .ctl_name = KERN_CORE_PATTERN,
227 .procname = "core_pattern",
228 .data = core_pattern,
d025c9db 229 .maxlen = 128,
1da177e4
LT		 230 .mode = 0644,
231 .proc_handler = &proc_dostring,
232 .strategy = &sysctl_string,
233 },
34f5a398 234#ifdef CONFIG_PROC_SYSCTL
1da177e4
LT		 235 {
236 .ctl_name = KERN_TAINTED,
237 .procname = "tainted",
238 .data = &tainted,
239 .maxlen = sizeof(int),
34f5a398
TT		 240 .mode = 0644,
241 .proc_handler = &proc_dointvec_taint,
1da177e4 242 },
34f5a398 243#endif
1da177e4
LT		 244 {
245 .ctl_name = KERN_CAP_BSET,
246 .procname = "cap-bound",
247 .data = &cap_bset,
248 .maxlen = sizeof(kernel_cap_t),
249 .mode = 0600,
250 .proc_handler = &proc_dointvec_bset,
251 },
252#ifdef CONFIG_BLK_DEV_INITRD
253 {
254 .ctl_name = KERN_REALROOTDEV,
255 .procname = "real-root-dev",
256 .data = &real_root_dev,
257 .maxlen = sizeof(int),
258 .mode = 0644,
259 .proc_handler = &proc_dointvec,
260 },
261#endif
262#ifdef __sparc__
263 {
264 .ctl_name = KERN_SPARC_REBOOT,
265 .procname = "reboot-cmd",
266 .data = reboot_command,
267 .maxlen = 256,
268 .mode = 0644,
269 .proc_handler = &proc_dostring,
270 .strategy = &sysctl_string,
271 },
272 {
273 .ctl_name = KERN_SPARC_STOP_A,
274 .procname = "stop-a",
275 .data = &stop_a_enabled,
276 .maxlen = sizeof (int),
277 .mode = 0644,
278 .proc_handler = &proc_dointvec,
279 },
280 {
281 .ctl_name = KERN_SPARC_SCONS_PWROFF,
282 .procname = "scons-poweroff",
283 .data = &scons_pwroff,
284 .maxlen = sizeof (int),
285 .mode = 0644,
286 .proc_handler = &proc_dointvec,
287 },
288#endif
289#ifdef __hppa__
290 {
291 .ctl_name = KERN_HPPA_PWRSW,
292 .procname = "soft-power",
293 .data = &pwrsw_enabled,
294 .maxlen = sizeof (int),
295 .mode = 0644,
296 .proc_handler = &proc_dointvec,
297 },
298 {
299 .ctl_name = KERN_HPPA_UNALIGNED,
300 .procname = "unaligned-trap",
301 .data = &unaligned_enabled,
302 .maxlen = sizeof (int),
303 .mode = 0644,
304 .proc_handler = &proc_dointvec,
305 },
306#endif
307 {
308 .ctl_name = KERN_CTLALTDEL,
309 .procname = "ctrl-alt-del",
310 .data = &C_A_D,
311 .maxlen = sizeof(int),
312 .mode = 0644,
313 .proc_handler = &proc_dointvec,
314 },
315 {
316 .ctl_name = KERN_PRINTK,
317 .procname = "printk",
318 .data = &console_loglevel,
319 .maxlen = 4*sizeof(int),
320 .mode = 0644,
321 .proc_handler = &proc_dointvec,
322 },
323#ifdef CONFIG_KMOD
324 {
325 .ctl_name = KERN_MODPROBE,
326 .procname = "modprobe",
327 .data = &modprobe_path,
328 .maxlen = KMOD_PATH_LEN,
329 .mode = 0644,
330 .proc_handler = &proc_dostring,
331 .strategy = &sysctl_string,
332 },
333#endif
57ae2508 334#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
1da177e4
LT		 335 {
336 .ctl_name = KERN_HOTPLUG,
337 .procname = "hotplug",
312c004d
KS		 338 .data = &uevent_helper,
339 .maxlen = UEVENT_HELPER_PATH_LEN,
1da177e4
LT		 340 .mode = 0644,
341 .proc_handler = &proc_dostring,
342 .strategy = &sysctl_string,
343 },
344#endif
345#ifdef CONFIG_CHR_DEV_SG
346 {
347 .ctl_name = KERN_SG_BIG_BUFF,
348 .procname = "sg-big-buff",
349 .data = &sg_big_buff,
350 .maxlen = sizeof (int),
351 .mode = 0444,
352 .proc_handler = &proc_dointvec,
353 },
354#endif
355#ifdef CONFIG_BSD_PROCESS_ACCT
356 {
357 .ctl_name = KERN_ACCT,
358 .procname = "acct",
359 .data = &acct_parm,
360 .maxlen = 3*sizeof(int),
361 .mode = 0644,
362 .proc_handler = &proc_dointvec,
363 },
364#endif
1da177e4
LT		 365#ifdef CONFIG_MAGIC_SYSRQ
366 {
367 .ctl_name = KERN_SYSRQ,
368 .procname = "sysrq",
5d6f647f 369 .data = &__sysrq_enabled,
1da177e4
LT		 370 .maxlen = sizeof (int),
371 .mode = 0644,
372 .proc_handler = &proc_dointvec,
373 },
374#endif
d6f8ff73 375#ifdef CONFIG_PROC_SYSCTL
1da177e4
LT		 376 {
377 .ctl_name = KERN_CADPID,
378 .procname = "cad_pid",
9ec52099 379 .data = NULL,
1da177e4
LT		 380 .maxlen = sizeof (int),
381 .mode = 0600,
9ec52099 382 .proc_handler = &proc_do_cad_pid,
1da177e4 383 },
d6f8ff73 384#endif
1da177e4
LT		 385 {
386 .ctl_name = KERN_MAX_THREADS,
387 .procname = "threads-max",
388 .data = &max_threads,
389 .maxlen = sizeof(int),
390 .mode = 0644,
391 .proc_handler = &proc_dointvec,
392 },
393 {
394 .ctl_name = KERN_RANDOM,
395 .procname = "random",
396 .mode = 0555,
397 .child = random_table,
398 },
399#ifdef CONFIG_UNIX98_PTYS
400 {
401 .ctl_name = KERN_PTY,
402 .procname = "pty",
403 .mode = 0555,
404 .child = pty_table,
405 },
406#endif
407 {
408 .ctl_name = KERN_OVERFLOWUID,
409 .procname = "overflowuid",
410 .data = &overflowuid,
411 .maxlen = sizeof(int),
412 .mode = 0644,
413 .proc_handler = &proc_dointvec_minmax,
414 .strategy = &sysctl_intvec,
415 .extra1 = &minolduid,
416 .extra2 = &maxolduid,
417 },
418 {
419 .ctl_name = KERN_OVERFLOWGID,
420 .procname = "overflowgid",
421 .data = &overflowgid,
422 .maxlen = sizeof(int),
423 .mode = 0644,
424 .proc_handler = &proc_dointvec_minmax,
425 .strategy = &sysctl_intvec,
426 .extra1 = &minolduid,
427 .extra2 = &maxolduid,
428 },
347a8dc3 429#ifdef CONFIG_S390
1da177e4
LT		 430#ifdef CONFIG_MATHEMU
431 {
432 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
433 .procname = "ieee_emulation_warnings",
434 .data = &sysctl_ieee_emulation_warnings,
435 .maxlen = sizeof(int),
436 .mode = 0644,
437 .proc_handler = &proc_dointvec,
438 },
439#endif
440#ifdef CONFIG_NO_IDLE_HZ
441 {
442 .ctl_name = KERN_HZ_TIMER,
443 .procname = "hz_timer",
444 .data = &sysctl_hz_timer,
445 .maxlen = sizeof(int),
446 .mode = 0644,
447 .proc_handler = &proc_dointvec,
448 },
449#endif
450 {
451 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
452 .procname = "userprocess_debug",
453 .data = &sysctl_userprocess_debug,
454 .maxlen = sizeof(int),
455 .mode = 0644,
456 .proc_handler = &proc_dointvec,
457 },
458#endif
459 {
460 .ctl_name = KERN_PIDMAX,
461 .procname = "pid_max",
462 .data = &pid_max,
463 .maxlen = sizeof (int),
464 .mode = 0644,
465 .proc_handler = &proc_dointvec_minmax,
466 .strategy = sysctl_intvec,
467 .extra1 = &pid_max_min,
468 .extra2 = &pid_max_max,
469 },
470 {
471 .ctl_name = KERN_PANIC_ON_OOPS,
472 .procname = "panic_on_oops",
473 .data = &panic_on_oops,
474 .maxlen = sizeof(int),
475 .mode = 0644,
476 .proc_handler = &proc_dointvec,
477 },
478 {
479 .ctl_name = KERN_PRINTK_RATELIMIT,
480 .procname = "printk_ratelimit",
481 .data = &printk_ratelimit_jiffies,
482 .maxlen = sizeof(int),
483 .mode = 0644,
484 .proc_handler = &proc_dointvec_jiffies,
485 .strategy = &sysctl_jiffies,
486 },
487 {
488 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
489 .procname = "printk_ratelimit_burst",
490 .data = &printk_ratelimit_burst,
491 .maxlen = sizeof(int),
492 .mode = 0644,
493 .proc_handler = &proc_dointvec,
494 },
495 {
496 .ctl_name = KERN_NGROUPS_MAX,
497 .procname = "ngroups_max",
498 .data = &ngroups_max,
499 .maxlen = sizeof (int),
500 .mode = 0444,
501 .proc_handler = &proc_dointvec,
502 },
503#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
504 {
505 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
506 .procname = "unknown_nmi_panic",
507 .data = &unknown_nmi_panic,
508 .maxlen = sizeof (int),
509 .mode = 0644,
2fbe7b25 510 .proc_handler = &proc_dointvec,
1da177e4 511 },
407984f1
DZ		 512 {
513 .ctl_name = KERN_NMI_WATCHDOG,
514 .procname = "nmi_watchdog",
515 .data = &nmi_watchdog_enabled,
516 .maxlen = sizeof (int),
517 .mode = 0644,
518 .proc_handler = &proc_nmi_enabled,
1da177e4
LT		 519 },
520#endif
521#if defined(CONFIG_X86)
8da5adda
DZ		 522 {
523 .ctl_name = KERN_PANIC_ON_NMI,
524 .procname = "panic_on_unrecovered_nmi",
525 .data = &panic_on_unrecovered_nmi,
526 .maxlen = sizeof(int),
527 .mode = 0644,
528 .proc_handler = &proc_dointvec,
529 },
1da177e4
LT		 530 {
531 .ctl_name = KERN_BOOTLOADER_TYPE,
532 .procname = "bootloader_type",
533 .data = &bootloader_type,
534 .maxlen = sizeof (int),
535 .mode = 0444,
536 .proc_handler = &proc_dointvec,
537 },
0741f4d2
CE		 538 {
539 .ctl_name = CTL_UNNUMBERED,
540 .procname = "kstack_depth_to_print",
541 .data = &kstack_depth_to_print,
542 .maxlen = sizeof(int),
543 .mode = 0644,
544 .proc_handler = &proc_dointvec,
545 },
1da177e4 546#endif
7a9166e3 547#if defined(CONFIG_MMU)
1da177e4
LT		 548 {
549 .ctl_name = KERN_RANDOMIZE,
550 .procname = "randomize_va_space",
551 .data = &randomize_va_space,
552 .maxlen = sizeof(int),
553 .mode = 0644,
554 .proc_handler = &proc_dointvec,
555 },
7a9166e3 556#endif
0152fb37 557#if defined(CONFIG_S390) && defined(CONFIG_SMP)
951f22d5
MS		 558 {
559 .ctl_name = KERN_SPIN_RETRY,
560 .procname = "spin_retry",
561 .data = &spin_retry,
562 .maxlen = sizeof (int),
563 .mode = 0644,
564 .proc_handler = &proc_dointvec,
565 },
c255d844
PM		 566#endif
567#ifdef CONFIG_ACPI_SLEEP
568 {
569 .ctl_name = KERN_ACPI_VIDEO_FLAGS,
570 .procname = "acpi_video_flags",
571 .data = &acpi_video_flags,
572 .maxlen = sizeof (unsigned long),
573 .mode = 0644,
7f99f06f 574 .proc_handler = &proc_doulongvec_minmax,
c255d844 575 },
d2b176ed
JS		 576#endif
577#ifdef CONFIG_IA64
578 {
579 .ctl_name = KERN_IA64_UNALIGNED,
580 .procname = "ignore-unaligned-usertrap",
581 .data = &no_unaligned_warning,
582 .maxlen = sizeof (int),
583 .mode = 0644,
584 .proc_handler = &proc_dointvec,
585 },
bebfa101
AK		 586#endif
587#ifdef CONFIG_COMPAT
588 {
589 .ctl_name = KERN_COMPAT_LOG,
590 .procname = "compat-log",
591 .data = &compat_log,
592 .maxlen = sizeof (int),
593 .mode = 0644,
594 .proc_handler = &proc_dointvec,
595 },
951f22d5 596#endif
23f78d4a
IM		 597#ifdef CONFIG_RT_MUTEXES
598 {
599 .ctl_name = KERN_MAX_LOCK_DEPTH,
600 .procname = "max_lock_depth",
601 .data = &max_lock_depth,
602 .maxlen = sizeof(int),
603 .mode = 0644,
604 .proc_handler = &proc_dointvec,
605 },
606#endif
5096add8
KC		 607#ifdef CONFIG_PROC_FS
608 {
609 .ctl_name = CTL_UNNUMBERED,
610 .procname = "maps_protect",
611 .data = &maps_protect,
612 .maxlen = sizeof(int),
613 .mode = 0644,
614 .proc_handler = &proc_dointvec,
615 },
616#endif
23f78d4a 617
1da177e4
LT		 618 { .ctl_name = 0 }
619};
620
621/* Constants for minimum and maximum testing in vm_table.
622 We use these as one-element integer vectors. */
623static int zero;
624static int one_hundred = 100;
625
626
627static ctl_table vm_table[] = {
628 {
629 .ctl_name = VM_OVERCOMMIT_MEMORY,
630 .procname = "overcommit_memory",
631 .data = &sysctl_overcommit_memory,
632 .maxlen = sizeof(sysctl_overcommit_memory),
633 .mode = 0644,
634 .proc_handler = &proc_dointvec,
635 },
fadd8fbd
KH		 636 {
637 .ctl_name = VM_PANIC_ON_OOM,
638 .procname = "panic_on_oom",
639 .data = &sysctl_panic_on_oom,
640 .maxlen = sizeof(sysctl_panic_on_oom),
641 .mode = 0644,
642 .proc_handler = &proc_dointvec,
643 },
1da177e4
LT		 644 {
645 .ctl_name = VM_OVERCOMMIT_RATIO,
646 .procname = "overcommit_ratio",
647 .data = &sysctl_overcommit_ratio,
648 .maxlen = sizeof(sysctl_overcommit_ratio),
649 .mode = 0644,
650 .proc_handler = &proc_dointvec,
651 },
652 {
653 .ctl_name = VM_PAGE_CLUSTER,
654 .procname = "page-cluster",
655 .data = &page_cluster,
656 .maxlen = sizeof(int),
657 .mode = 0644,
658 .proc_handler = &proc_dointvec,
659 },
660 {
661 .ctl_name = VM_DIRTY_BACKGROUND,
662 .procname = "dirty_background_ratio",
663 .data = &dirty_background_ratio,
664 .maxlen = sizeof(dirty_background_ratio),
665 .mode = 0644,
666 .proc_handler = &proc_dointvec_minmax,
667 .strategy = &sysctl_intvec,
668 .extra1 = &zero,
669 .extra2 = &one_hundred,
670 },
671 {
672 .ctl_name = VM_DIRTY_RATIO,
673 .procname = "dirty_ratio",
674 .data = &vm_dirty_ratio,
675 .maxlen = sizeof(vm_dirty_ratio),
676 .mode = 0644,
677 .proc_handler = &proc_dointvec_minmax,
678 .strategy = &sysctl_intvec,
679 .extra1 = &zero,
680 .extra2 = &one_hundred,
681 },
682 {
683 .ctl_name = VM_DIRTY_WB_CS,
684 .procname = "dirty_writeback_centisecs",
f6ef9438
BS		 685 .data = &dirty_writeback_interval,
686 .maxlen = sizeof(dirty_writeback_interval),
1da177e4
LT		 687 .mode = 0644,
688 .proc_handler = &dirty_writeback_centisecs_handler,
689 },
690 {
691 .ctl_name = VM_DIRTY_EXPIRE_CS,
692 .procname = "dirty_expire_centisecs",
f6ef9438
BS		 693 .data = &dirty_expire_interval,
694 .maxlen = sizeof(dirty_expire_interval),
1da177e4 695 .mode = 0644,
f6ef9438 696 .proc_handler = &proc_dointvec_userhz_jiffies,
1da177e4
LT		 697 },
698 {
699 .ctl_name = VM_NR_PDFLUSH_THREADS,
700 .procname = "nr_pdflush_threads",
701 .data = &nr_pdflush_threads,
702 .maxlen = sizeof nr_pdflush_threads,
703 .mode = 0444 /* read-only*/,
704 .proc_handler = &proc_dointvec,
705 },
706 {
707 .ctl_name = VM_SWAPPINESS,
708 .procname = "swappiness",
709 .data = &vm_swappiness,
710 .maxlen = sizeof(vm_swappiness),
711 .mode = 0644,
712 .proc_handler = &proc_dointvec_minmax,
713 .strategy = &sysctl_intvec,
714 .extra1 = &zero,
715 .extra2 = &one_hundred,
716 },
717#ifdef CONFIG_HUGETLB_PAGE
718 {
719 .ctl_name = VM_HUGETLB_PAGES,
720 .procname = "nr_hugepages",
721 .data = &max_huge_pages,
722 .maxlen = sizeof(unsigned long),
723 .mode = 0644,
724 .proc_handler = &hugetlb_sysctl_handler,
725 .extra1 = (void *)&hugetlb_zero,
726 .extra2 = (void *)&hugetlb_infinity,
727 },
728 {
729 .ctl_name = VM_HUGETLB_GROUP,
730 .procname = "hugetlb_shm_group",
731 .data = &sysctl_hugetlb_shm_group,
732 .maxlen = sizeof(gid_t),
733 .mode = 0644,
734 .proc_handler = &proc_dointvec,
735 },
736#endif
737 {
738 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
739 .procname = "lowmem_reserve_ratio",
740 .data = &sysctl_lowmem_reserve_ratio,
741 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
742 .mode = 0644,
743 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
744 .strategy = &sysctl_intvec,
745 },
9d0243bc
AM		 746 {
747 .ctl_name = VM_DROP_PAGECACHE,
748 .procname = "drop_caches",
749 .data = &sysctl_drop_caches,
750 .maxlen = sizeof(int),
751 .mode = 0644,
752 .proc_handler = drop_caches_sysctl_handler,
753 .strategy = &sysctl_intvec,
754 },
1da177e4
LT		 755 {
756 .ctl_name = VM_MIN_FREE_KBYTES,
757 .procname = "min_free_kbytes",
758 .data = &min_free_kbytes,
759 .maxlen = sizeof(min_free_kbytes),
760 .mode = 0644,
761 .proc_handler = &min_free_kbytes_sysctl_handler,
762 .strategy = &sysctl_intvec,
763 .extra1 = &zero,
764 },
8ad4b1fb
RS		 765 {
766 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
767 .procname = "percpu_pagelist_fraction",
768 .data = &percpu_pagelist_fraction,
769 .maxlen = sizeof(percpu_pagelist_fraction),
770 .mode = 0644,
771 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
772 .strategy = &sysctl_intvec,
773 .extra1 = &min_percpu_pagelist_fract,
774 },
1da177e4
LT		 775#ifdef CONFIG_MMU
776 {
777 .ctl_name = VM_MAX_MAP_COUNT,
778 .procname = "max_map_count",
779 .data = &sysctl_max_map_count,
780 .maxlen = sizeof(sysctl_max_map_count),
781 .mode = 0644,
782 .proc_handler = &proc_dointvec
783 },
784#endif
785 {
786 .ctl_name = VM_LAPTOP_MODE,
787 .procname = "laptop_mode",
788 .data = &laptop_mode,
789 .maxlen = sizeof(laptop_mode),
790 .mode = 0644,
ed5b43f1
BS		 791 .proc_handler = &proc_dointvec_jiffies,
792 .strategy = &sysctl_jiffies,
1da177e4
LT		 793 },
794 {
795 .ctl_name = VM_BLOCK_DUMP,
796 .procname = "block_dump",
797 .data = &block_dump,
798 .maxlen = sizeof(block_dump),
799 .mode = 0644,
800 .proc_handler = &proc_dointvec,
801 .strategy = &sysctl_intvec,
802 .extra1 = &zero,
803 },
804 {
805 .ctl_name = VM_VFS_CACHE_PRESSURE,
806 .procname = "vfs_cache_pressure",
807 .data = &sysctl_vfs_cache_pressure,
808 .maxlen = sizeof(sysctl_vfs_cache_pressure),
809 .mode = 0644,
810 .proc_handler = &proc_dointvec,
811 .strategy = &sysctl_intvec,
812 .extra1 = &zero,
813 },
814#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
815 {
816 .ctl_name = VM_LEGACY_VA_LAYOUT,
817 .procname = "legacy_va_layout",
818 .data = &sysctl_legacy_va_layout,
819 .maxlen = sizeof(sysctl_legacy_va_layout),
820 .mode = 0644,
821 .proc_handler = &proc_dointvec,
822 .strategy = &sysctl_intvec,
823 .extra1 = &zero,
824 },
825#endif
1743660b
CL		 826#ifdef CONFIG_NUMA
827 {
828 .ctl_name = VM_ZONE_RECLAIM_MODE,
829 .procname = "zone_reclaim_mode",
830 .data = &zone_reclaim_mode,
831 .maxlen = sizeof(zone_reclaim_mode),
832 .mode = 0644,
833 .proc_handler = &proc_dointvec,
c84db23c
CL		 834 .strategy = &sysctl_intvec,
835 .extra1 = &zero,
1743660b 836 },
9614634f
CL		 837 {
838 .ctl_name = VM_MIN_UNMAPPED,
839 .procname = "min_unmapped_ratio",
840 .data = &sysctl_min_unmapped_ratio,
841 .maxlen = sizeof(sysctl_min_unmapped_ratio),
842 .mode = 0644,
843 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
844 .strategy = &sysctl_intvec,
845 .extra1 = &zero,
846 .extra2 = &one_hundred,
847 },
0ff38490
CL		 848 {
849 .ctl_name = VM_MIN_SLAB,
850 .procname = "min_slab_ratio",
851 .data = &sysctl_min_slab_ratio,
852 .maxlen = sizeof(sysctl_min_slab_ratio),
853 .mode = 0644,
854 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
855 .strategy = &sysctl_intvec,
856 .extra1 = &zero,
857 .extra2 = &one_hundred,
858 },
e6e5494c 859#endif
5c36e657
PM		 860#if defined(CONFIG_X86_32) || \
861 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
e6e5494c
IM		 862 {
863 .ctl_name = VM_VDSO_ENABLED,
864 .procname = "vdso_enabled",
865 .data = &vdso_enabled,
866 .maxlen = sizeof(vdso_enabled),
867 .mode = 0644,
868 .proc_handler = &proc_dointvec,
869 .strategy = &sysctl_intvec,
870 .extra1 = &zero,
871 },
1da177e4
LT		 872#endif
873 { .ctl_name = 0 }
874};
875
2abc26fc
EB		 876#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
877static ctl_table binfmt_misc_table[] = {
878 { .ctl_name = 0 }
879};
880#endif
881
1da177e4
LT		 882static ctl_table fs_table[] = {
883 {
884 .ctl_name = FS_NRINODE,
885 .procname = "inode-nr",
886 .data = &inodes_stat,
887 .maxlen = 2*sizeof(int),
888 .mode = 0444,
889 .proc_handler = &proc_dointvec,
890 },
891 {
892 .ctl_name = FS_STATINODE,
893 .procname = "inode-state",
894 .data = &inodes_stat,
895 .maxlen = 7*sizeof(int),
896 .mode = 0444,
897 .proc_handler = &proc_dointvec,
898 },
899 {
900 .ctl_name = FS_NRFILE,
901 .procname = "file-nr",
902 .data = &files_stat,
903 .maxlen = 3*sizeof(int),
904 .mode = 0444,
529bf6be 905 .proc_handler = &proc_nr_files,
1da177e4
LT		 906 },
907 {
908 .ctl_name = FS_MAXFILE,
909 .procname = "file-max",
910 .data = &files_stat.max_files,
911 .maxlen = sizeof(int),
912 .mode = 0644,
913 .proc_handler = &proc_dointvec,
914 },
915 {
916 .ctl_name = FS_DENTRY,
917 .procname = "dentry-state",
918 .data = &dentry_stat,
919 .maxlen = 6*sizeof(int),
920 .mode = 0444,
921 .proc_handler = &proc_dointvec,
922 },
923 {
924 .ctl_name = FS_OVERFLOWUID,
925 .procname = "overflowuid",
926 .data = &fs_overflowuid,
927 .maxlen = sizeof(int),
928 .mode = 0644,
929 .proc_handler = &proc_dointvec_minmax,
930 .strategy = &sysctl_intvec,
931 .extra1 = &minolduid,
932 .extra2 = &maxolduid,
933 },
934 {
935 .ctl_name = FS_OVERFLOWGID,
936 .procname = "overflowgid",
937 .data = &fs_overflowgid,
938 .maxlen = sizeof(int),
939 .mode = 0644,
940 .proc_handler = &proc_dointvec_minmax,
941 .strategy = &sysctl_intvec,
942 .extra1 = &minolduid,
943 .extra2 = &maxolduid,
944 },
945 {
946 .ctl_name = FS_LEASES,
947 .procname = "leases-enable",
948 .data = &leases_enable,
949 .maxlen = sizeof(int),
950 .mode = 0644,
951 .proc_handler = &proc_dointvec,
952 },
953#ifdef CONFIG_DNOTIFY
954 {
955 .ctl_name = FS_DIR_NOTIFY,
956 .procname = "dir-notify-enable",
957 .data = &dir_notify_enable,
958 .maxlen = sizeof(int),
959 .mode = 0644,
960 .proc_handler = &proc_dointvec,
961 },
962#endif
963#ifdef CONFIG_MMU
964 {
965 .ctl_name = FS_LEASE_TIME,
966 .procname = "lease-break-time",
967 .data = &lease_break_time,
968 .maxlen = sizeof(int),
969 .mode = 0644,
970 .proc_handler = &proc_dointvec,
971 },
972 {
973 .ctl_name = FS_AIO_NR,
974 .procname = "aio-nr",
975 .data = &aio_nr,
976 .maxlen = sizeof(aio_nr),
977 .mode = 0444,
d55b5fda 978 .proc_handler = &proc_doulongvec_minmax,
1da177e4
LT		 979 },
980 {
981 .ctl_name = FS_AIO_MAX_NR,
982 .procname = "aio-max-nr",
983 .data = &aio_max_nr,
984 .maxlen = sizeof(aio_max_nr),
985 .mode = 0644,
d55b5fda 986 .proc_handler = &proc_doulongvec_minmax,
1da177e4 987 },
2d9048e2 988#ifdef CONFIG_INOTIFY_USER
0399cb08
RL		 989 {
990 .ctl_name = FS_INOTIFY,
991 .procname = "inotify",
992 .mode = 0555,
993 .child = inotify_table,
994 },
995#endif
1da177e4 996#endif
d6e71144
AC		 997 {
998 .ctl_name = KERN_SETUID_DUMPABLE,
999 .procname = "suid_dumpable",
1000 .data = &suid_dumpable,
1001 .maxlen = sizeof(int),
1002 .mode = 0644,
1003 .proc_handler = &proc_dointvec,
1004 },
2abc26fc
EB		 1005#if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1006 {
1007 .ctl_name = CTL_UNNUMBERED,
1008 .procname = "binfmt_misc",
1009 .mode = 0555,
1010 .child = binfmt_misc_table,
1011 },
1012#endif
1da177e4
LT		 1013 { .ctl_name = 0 }
1014};
1015
1016static ctl_table debug_table[] = {
1017 { .ctl_name = 0 }
1018};
1019
1020static ctl_table dev_table[] = {
1021 { .ctl_name = 0 }
0eeca283 1022};
1da177e4 1023
330d57fb
AV		 1024static DEFINE_SPINLOCK(sysctl_lock);
1025
1026/* called under sysctl_lock */
1027static int use_table(struct ctl_table_header *p)
1028{
1029 if (unlikely(p->unregistering))
1030 return 0;
1031 p->used++;
1032 return 1;
1033}
1034
1035/* called under sysctl_lock */
1036static void unuse_table(struct ctl_table_header *p)
1037{
1038 if (!--p->used)
1039 if (unlikely(p->unregistering))
1040 complete(p->unregistering);
1041}
1042
1043/* called under sysctl_lock, will reacquire if has to wait */
1044static void start_unregistering(struct ctl_table_header *p)
1045{
1046 /*
1047 * if p->used is 0, nobody will ever touch that entry again;
1048 * we'll eliminate all paths to it before dropping sysctl_lock
1049 */
1050 if (unlikely(p->used)) {
1051 struct completion wait;
1052 init_completion(&wait);
1053 p->unregistering = &wait;
1054 spin_unlock(&sysctl_lock);
1055 wait_for_completion(&wait);
1056 spin_lock(&sysctl_lock);
1057 }
1058 /*
1059 * do not remove from the list until nobody holds it; walking the
1060 * list in do_sysctl() relies on that.
1061 */
1062 list_del_init(&p->ctl_entry);
1063}
1064
805b5d5e
EB		 1065void sysctl_head_finish(struct ctl_table_header *head)
1066{
1067 if (!head)
1068 return;
1069 spin_lock(&sysctl_lock);
1070 unuse_table(head);
1071 spin_unlock(&sysctl_lock);
1072}
1073
1074struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1075{
1076 struct ctl_table_header *head;
1077 struct list_head *tmp;
1078 spin_lock(&sysctl_lock);
1079 if (prev) {
1080 tmp = &prev->ctl_entry;
1081 unuse_table(prev);
1082 goto next;
1083 }
1084 tmp = &root_table_header.ctl_entry;
1085 for (;;) {
1086 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1087
1088 if (!use_table(head))
1089 goto next;
1090 spin_unlock(&sysctl_lock);
1091 return head;
1092 next:
1093 tmp = tmp->next;
1094 if (tmp == &root_table_header.ctl_entry)
1095 break;
1096 }
1097 spin_unlock(&sysctl_lock);
1098 return NULL;
1099}
1100
b89a8171 1101#ifdef CONFIG_SYSCTL_SYSCALL
1da177e4
LT		 1102int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1103 void __user *newval, size_t newlen)
1104{
805b5d5e 1105 struct ctl_table_header *head;
330d57fb 1106 int error = -ENOTDIR;
1da177e4
LT		 1107
1108 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1109 return -ENOTDIR;
1110 if (oldval) {
1111 int old_len;
1112 if (!oldlenp || get_user(old_len, oldlenp))
1113 return -EFAULT;
1114 }
330d57fb 1115
805b5d5e
EB		 1116 for (head = sysctl_head_next(NULL); head;
1117 head = sysctl_head_next(head)) {
330d57fb 1118 error = parse_table(name, nlen, oldval, oldlenp,
1f29bcd7 1119 newval, newlen, head->ctl_table);
805b5d5e
EB		 1120 if (error != -ENOTDIR) {
1121 sysctl_head_finish(head);
330d57fb 1122 break;
805b5d5e
EB		 1123 }
1124 }
330d57fb 1125 return error;
1da177e4
LT		 1126}
1127
1128asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1129{
1130 struct __sysctl_args tmp;
1131 int error;
1132
1133 if (copy_from_user(&tmp, args, sizeof(tmp)))
1134 return -EFAULT;
1135
1136 lock_kernel();
1137 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1138 tmp.newval, tmp.newlen);
1139 unlock_kernel();
1140 return error;
1141}
b89a8171 1142#endif /* CONFIG_SYSCTL_SYSCALL */
1da177e4
LT		 1143
1144/*
1ff007eb 1145 * sysctl_perm does NOT grant the superuser all rights automatically, because
1da177e4
LT		 1146 * some sysctl variables are readonly even to root.
1147 */
1148
1149static int test_perm(int mode, int op)
1150{
1151 if (!current->euid)
1152 mode >>= 6;
1153 else if (in_egroup_p(0))
1154 mode >>= 3;
1155 if ((mode & op & 0007) == op)
1156 return 0;
1157 return -EACCES;
1158}
1159
1ff007eb 1160int sysctl_perm(ctl_table *table, int op)
1da177e4
LT		 1161{
1162 int error;
1163 error = security_sysctl(table, op);
1164 if (error)
1165 return error;
1166 return test_perm(table->mode, op);
1167}
1168
b89a8171 1169#ifdef CONFIG_SYSCTL_SYSCALL
1da177e4
LT		 1170static int parse_table(int __user *name, int nlen,
1171 void __user *oldval, size_t __user *oldlenp,
1172 void __user *newval, size_t newlen,
1f29bcd7 1173 ctl_table *table)
1da177e4
LT		 1174{
1175 int n;
1176repeat:
1177 if (!nlen)
1178 return -ENOTDIR;
1179 if (get_user(n, name))
1180 return -EFAULT;
d99f160a
EB		 1181 for ( ; table->ctl_name || table->procname; table++) {
1182 if (!table->ctl_name)
1183 continue;
6703ddfc 1184 if (n == table->ctl_name) {
1da177e4
LT		 1185 int error;
1186 if (table->child) {
1ff007eb 1187 if (sysctl_perm(table, 001))
1da177e4 1188 return -EPERM;
1da177e4
LT		 1189 name++;
1190 nlen--;
1191 table = table->child;
1192 goto repeat;
1193 }
1194 error = do_sysctl_strategy(table, name, nlen,
1195 oldval, oldlenp,
1f29bcd7 1196 newval, newlen);
1da177e4
LT		 1197 return error;
1198 }
1199 }
1200 return -ENOTDIR;
1201}
1202
1203/* Perform the actual read/write of a sysctl table entry. */
1204int do_sysctl_strategy (ctl_table *table,
1205 int __user *name, int nlen,
1206 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 1207 void __user *newval, size_t newlen)
1da177e4
LT		 1208{
1209 int op = 0, rc;
1210 size_t len;
1211
1212 if (oldval)
1213 op |= 004;
1214 if (newval)
1215 op |= 002;
1ff007eb 1216 if (sysctl_perm(table, op))
1da177e4
LT		 1217 return -EPERM;
1218
1219 if (table->strategy) {
1220 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1f29bcd7 1221 newval, newlen);
1da177e4
LT		 1222 if (rc < 0)
1223 return rc;
1224 if (rc > 0)
1225 return 0;
1226 }
1227
1228 /* If there is no strategy routine, or if the strategy returns
1229 * zero, proceed with automatic r/w */
1230 if (table->data && table->maxlen) {
1231 if (oldval && oldlenp) {
1232 if (get_user(len, oldlenp))
1233 return -EFAULT;
1234 if (len) {
1235 if (len > table->maxlen)
1236 len = table->maxlen;
1237 if(copy_to_user(oldval, table->data, len))
1238 return -EFAULT;
1239 if(put_user(len, oldlenp))
1240 return -EFAULT;
1241 }
1242 }
1243 if (newval && newlen) {
1244 len = newlen;
1245 if (len > table->maxlen)
1246 len = table->maxlen;
1247 if(copy_from_user(table->data, newval, len))
1248 return -EFAULT;
1249 }
1250 }
1251 return 0;
1252}
b89a8171 1253#endif /* CONFIG_SYSCTL_SYSCALL */
1da177e4 1254
d912b0cc
EB		 1255static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1256{
1257 for (; table->ctl_name || table->procname; table++) {
1258 table->parent = parent;
1259 if (table->child)
1260 sysctl_set_parent(table, table->child);
1261 }
1262}
1263
1264static __init int sysctl_init(void)
1265{
1266 sysctl_set_parent(NULL, root_table);
1267 return 0;
1268}
1269
1270core_initcall(sysctl_init);
1271
1da177e4
LT		 1272/**
1273 * register_sysctl_table - register a sysctl hierarchy
1274 * @table: the top-level table structure
1da177e4
LT		 1275 *
1276 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1277 * array. An entry with a ctl_name of 0 terminates the table.
1278 *
1279 * The members of the &ctl_table structure are used as follows:
1280 *
1281 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1282 * must be unique within that level of sysctl
1283 *
1284 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1285 * enter a sysctl file
1286 *
1287 * data - a pointer to data for use by proc_handler
1288 *
1289 * maxlen - the maximum size in bytes of the data
1290 *
1291 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1292 *
1293 * child - a pointer to the child sysctl table if this entry is a directory, or
1294 * %NULL.
1295 *
1296 * proc_handler - the text handler routine (described below)
1297 *
1298 * strategy - the strategy routine (described below)
1299 *
1300 * de - for internal use by the sysctl routines
1301 *
1302 * extra1, extra2 - extra pointers usable by the proc handler routines
1303 *
1304 * Leaf nodes in the sysctl tree will be represented by a single file
1305 * under /proc; non-leaf nodes will be represented by directories.
1306 *
1307 * sysctl(2) can automatically manage read and write requests through
1308 * the sysctl table. The data and maxlen fields of the ctl_table
1309 * struct enable minimal validation of the values being written to be
1310 * performed, and the mode field allows minimal authentication.
1311 *
1312 * More sophisticated management can be enabled by the provision of a
1313 * strategy routine with the table entry. This will be called before
1314 * any automatic read or write of the data is performed.
1315 *
1316 * The strategy routine may return
1317 *
1318 * < 0 - Error occurred (error is passed to user process)
1319 *
1320 * 0 - OK - proceed with automatic read or write.
1321 *
1322 * > 0 - OK - read or write has been done by the strategy routine, so
1323 * return immediately.
1324 *
1325 * There must be a proc_handler routine for any terminal nodes
1326 * mirrored under /proc/sys (non-terminals are handled by a built-in
1327 * directory handler). Several default handlers are available to
1328 * cover common cases -
1329 *
1330 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1331 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1332 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1333 *
1334 * It is the handler's job to read the input buffer from user memory
1335 * and process it. The handler should return 0 on success.
1336 *
1337 * This routine returns %NULL on a failure to register, and a pointer
1338 * to the table header on success.
1339 */
0b4d4147 1340struct ctl_table_header *register_sysctl_table(ctl_table * table)
1da177e4
LT		 1341{
1342 struct ctl_table_header *tmp;
1343 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1344 if (!tmp)
1345 return NULL;
1346 tmp->ctl_table = table;
1347 INIT_LIST_HEAD(&tmp->ctl_entry);
330d57fb
AV		 1348 tmp->used = 0;
1349 tmp->unregistering = NULL;
d912b0cc 1350 sysctl_set_parent(NULL, table);
330d57fb 1351 spin_lock(&sysctl_lock);
0b4d4147 1352 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
330d57fb 1353 spin_unlock(&sysctl_lock);
1da177e4
LT		 1354 return tmp;
1355}
1356
1357/**
1358 * unregister_sysctl_table - unregister a sysctl table hierarchy
1359 * @header: the header returned from register_sysctl_table
1360 *
1361 * Unregisters the sysctl table and all children. proc entries may not
1362 * actually be removed until they are no longer used by anyone.
1363 */
1364void unregister_sysctl_table(struct ctl_table_header * header)
1365{
330d57fb
AV		 1366 might_sleep();
1367 spin_lock(&sysctl_lock);
1368 start_unregistering(header);
330d57fb 1369 spin_unlock(&sysctl_lock);
1da177e4
LT		 1370 kfree(header);
1371}
1372
b89a8171 1373#else /* !CONFIG_SYSCTL */
93a6fefe 1374struct ctl_table_header *register_sysctl_table(ctl_table * table)
b89a8171
EB		 1375{
1376 return NULL;
1377}
1378
1379void unregister_sysctl_table(struct ctl_table_header * table)
1380{
1381}
1382
1383#endif /* CONFIG_SYSCTL */
1384
1da177e4
LT		 1385/*
1386 * /proc/sys support
1387 */
1388
b89a8171 1389#ifdef CONFIG_PROC_SYSCTL
1da177e4 1390
b1ba4ddd
AB		 1391static int _proc_do_string(void* data, int maxlen, int write,
1392 struct file *filp, void __user *buffer,
1393 size_t *lenp, loff_t *ppos)
1da177e4
LT		 1394{
1395 size_t len;
1396 char __user *p;
1397 char c;
8d060877
ON		 1398
1399 if (!data || !maxlen || !*lenp) {
1da177e4
LT		 1400 *lenp = 0;
1401 return 0;
1402 }
8d060877 1403
1da177e4
LT		 1404 if (write) {
1405 len = 0;
1406 p = buffer;
1407 while (len < *lenp) {
1408 if (get_user(c, p++))
1409 return -EFAULT;
1410 if (c == 0 || c == '\n')
1411 break;
1412 len++;
1413 }
f5dd3d6f
SV		 1414 if (len >= maxlen)
1415 len = maxlen-1;
1416 if(copy_from_user(data, buffer, len))
1da177e4 1417 return -EFAULT;
f5dd3d6f 1418 ((char *) data)[len] = 0;
1da177e4
LT		 1419 *ppos += *lenp;
1420 } else {
f5dd3d6f
SV		 1421 len = strlen(data);
1422 if (len > maxlen)
1423 len = maxlen;
8d060877
ON		 1424
1425 if (*ppos > len) {
1426 *lenp = 0;
1427 return 0;
1428 }
1429
1430 data += *ppos;
1431 len -= *ppos;
1432
1da177e4
LT		 1433 if (len > *lenp)
1434 len = *lenp;
1435 if (len)
f5dd3d6f 1436 if(copy_to_user(buffer, data, len))
1da177e4
LT		 1437 return -EFAULT;
1438 if (len < *lenp) {
1439 if(put_user('\n', ((char __user *) buffer) + len))
1440 return -EFAULT;
1441 len++;
1442 }
1443 *lenp = len;
1444 *ppos += len;
1445 }
1446 return 0;
1447}
1448
f5dd3d6f
SV		 1449/**
1450 * proc_dostring - read a string sysctl
1451 * @table: the sysctl table
1452 * @write: %TRUE if this is a write to the sysctl file
1453 * @filp: the file structure
1454 * @buffer: the user buffer
1455 * @lenp: the size of the user buffer
1456 * @ppos: file position
1457 *
1458 * Reads/writes a string from/to the user buffer. If the kernel
1459 * buffer provided is not large enough to hold the string, the
1460 * string is truncated. The copied string is %NULL-terminated.
1461 * If the string is being read by the user process, it is copied
1462 * and a newline '\n' is added. It is truncated if the buffer is
1463 * not large enough.
1464 *
1465 * Returns 0 on success.
1466 */
1467int proc_dostring(ctl_table *table, int write, struct file *filp,
1468 void __user *buffer, size_t *lenp, loff_t *ppos)
1469{
1470 return _proc_do_string(table->data, table->maxlen, write, filp,
1471 buffer, lenp, ppos);
1472}
1473
1da177e4
LT		 1474
1475static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1476 int *valp,
1477 int write, void *data)
1478{
1479 if (write) {
1480 *valp = *negp ? -*lvalp : *lvalp;
1481 } else {
1482 int val = *valp;
1483 if (val < 0) {
1484 *negp = -1;
1485 *lvalp = (unsigned long)-val;
1486 } else {
1487 *negp = 0;
1488 *lvalp = (unsigned long)val;
1489 }
1490 }
1491 return 0;
1492}
1493
fcfbd547
KK		 1494static int __do_proc_dointvec(void *tbl_data, ctl_table *table,
1495 int write, struct file *filp, void __user *buffer,
1496 size_t *lenp, loff_t *ppos,
1da177e4
LT		 1497 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1498 int write, void *data),
1499 void *data)
1500{
1501#define TMPBUFLEN 21
1502 int *i, vleft, first=1, neg, val;
1503 unsigned long lval;
1504 size_t left, len;
1505
1506 char buf[TMPBUFLEN], *p;
1507 char __user *s = buffer;
1508
fcfbd547 1509 if (!tbl_data || !table->maxlen || !*lenp ||
1da177e4
LT		 1510 (*ppos && !write)) {
1511 *lenp = 0;
1512 return 0;
1513 }
1514
fcfbd547 1515 i = (int *) tbl_data;
1da177e4
LT		 1516 vleft = table->maxlen / sizeof(*i);
1517 left = *lenp;
1518
1519 if (!conv)
1520 conv = do_proc_dointvec_conv;
1521
1522 for (; left && vleft--; i++, first=0) {
1523 if (write) {
1524 while (left) {
1525 char c;
1526 if (get_user(c, s))
1527 return -EFAULT;
1528 if (!isspace(c))
1529 break;
1530 left--;
1531 s++;
1532 }
1533 if (!left)
1534 break;
1535 neg = 0;
1536 len = left;
1537 if (len > sizeof(buf) - 1)
1538 len = sizeof(buf) - 1;
1539 if (copy_from_user(buf, s, len))
1540 return -EFAULT;
1541 buf[len] = 0;
1542 p = buf;
1543 if (*p == '-' && left > 1) {
1544 neg = 1;
bd9b0bac 1545 p++;
1da177e4
LT		 1546 }
1547 if (*p < '0' || *p > '9')
1548 break;
1549
1550 lval = simple_strtoul(p, &p, 0);
1551
1552 len = p-buf;
1553 if ((len < left) && *p && !isspace(*p))
1554 break;
1555 if (neg)
1556 val = -val;
1557 s += len;
1558 left -= len;
1559
1560 if (conv(&neg, &lval, i, 1, data))
1561 break;
1562 } else {
1563 p = buf;
1564 if (!first)
1565 *p++ = '\t';
1566
1567 if (conv(&neg, &lval, i, 0, data))
1568 break;
1569
1570 sprintf(p, "%s%lu", neg ? "-" : "", lval);
1571 len = strlen(buf);
1572 if (len > left)
1573 len = left;
1574 if(copy_to_user(s, buf, len))
1575 return -EFAULT;
1576 left -= len;
1577 s += len;
1578 }
1579 }
1580
1581 if (!write && !first && left) {
1582 if(put_user('\n', s))
1583 return -EFAULT;
1584 left--, s++;
1585 }
1586 if (write) {
1587 while (left) {
1588 char c;
1589 if (get_user(c, s++))
1590 return -EFAULT;
1591 if (!isspace(c))
1592 break;
1593 left--;
1594 }
1595 }
1596 if (write && first)
1597 return -EINVAL;
1598 *lenp -= left;
1599 *ppos += *lenp;
1600 return 0;
1601#undef TMPBUFLEN
1602}
1603
fcfbd547
KK		 1604static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1605 void __user *buffer, size_t *lenp, loff_t *ppos,
1606 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1607 int write, void *data),
1608 void *data)
1609{
1610 return __do_proc_dointvec(table->data, table, write, filp,
1611 buffer, lenp, ppos, conv, data);
1612}
1613
1da177e4
LT		 1614/**
1615 * proc_dointvec - read a vector of integers
1616 * @table: the sysctl table
1617 * @write: %TRUE if this is a write to the sysctl file
1618 * @filp: the file structure
1619 * @buffer: the user buffer
1620 * @lenp: the size of the user buffer
1621 * @ppos: file position
1622 *
1623 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1624 * values from/to the user buffer, treated as an ASCII string.
1625 *
1626 * Returns 0 on success.
1627 */
1628int proc_dointvec(ctl_table *table, int write, struct file *filp,
1629 void __user *buffer, size_t *lenp, loff_t *ppos)
1630{
1631 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1632 NULL,NULL);
1633}
1634
1635#define OP_SET 0
1636#define OP_AND 1
34f5a398 1637#define OP_OR 2
1da177e4
LT		 1638
1639static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1640 int *valp,
1641 int write, void *data)
1642{
1643 int op = *(int *)data;
1644 if (write) {
1645 int val = *negp ? -*lvalp : *lvalp;
1646 switch(op) {
1647 case OP_SET: *valp = val; break;
1648 case OP_AND: *valp &= val; break;
34f5a398 1649 case OP_OR: *valp |= val; break;
1da177e4
LT		 1650 }
1651 } else {
1652 int val = *valp;
1653 if (val < 0) {
1654 *negp = -1;
1655 *lvalp = (unsigned long)-val;
1656 } else {
1657 *negp = 0;
1658 *lvalp = (unsigned long)val;
1659 }
1660 }
1661 return 0;
1662}
1663
1664/*
1665 * init may raise the set.
1666 */
1667
1668int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1669 void __user *buffer, size_t *lenp, loff_t *ppos)
1670{
1671 int op;
1672
6ff1b442 1673 if (write && !capable(CAP_SYS_MODULE)) {
1da177e4
LT		 1674 return -EPERM;
1675 }
1676
f400e198 1677 op = is_init(current) ? OP_SET : OP_AND;
1da177e4
LT		 1678 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1679 do_proc_dointvec_bset_conv,&op);
1680}
1681
34f5a398
TT		 1682/*
1683 * Taint values can only be increased
1684 */
1685static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
1686 void __user *buffer, size_t *lenp, loff_t *ppos)
1687{
1688 int op;
1689
91fcd412 1690 if (write && !capable(CAP_SYS_ADMIN))
34f5a398
TT		 1691 return -EPERM;
1692
1693 op = OP_OR;
1694 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1695 do_proc_dointvec_bset_conv,&op);
1696}
1697
1da177e4
LT		 1698struct do_proc_dointvec_minmax_conv_param {
1699 int *min;
1700 int *max;
1701};
1702
1703static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1704 int *valp,
1705 int write, void *data)
1706{
1707 struct do_proc_dointvec_minmax_conv_param *param = data;
1708 if (write) {
1709 int val = *negp ? -*lvalp : *lvalp;
1710 if ((param->min && *param->min > val) ||
1711 (param->max && *param->max < val))
1712 return -EINVAL;
1713 *valp = val;
1714 } else {
1715 int val = *valp;
1716 if (val < 0) {
1717 *negp = -1;
1718 *lvalp = (unsigned long)-val;
1719 } else {
1720 *negp = 0;
1721 *lvalp = (unsigned long)val;
1722 }
1723 }
1724 return 0;
1725}
1726
1727/**
1728 * proc_dointvec_minmax - read a vector of integers with min/max values
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 * This routine will ensure the values are within the range specified by
1740 * table->extra1 (min) and table->extra2 (max).
1741 *
1742 * Returns 0 on success.
1743 */
1744int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1745 void __user *buffer, size_t *lenp, loff_t *ppos)
1746{
1747 struct do_proc_dointvec_minmax_conv_param param = {
1748 .min = (int *) table->extra1,
1749 .max = (int *) table->extra2,
1750 };
1751 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1752 do_proc_dointvec_minmax_conv, &param);
1753}
1754
fcfbd547 1755static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
1da177e4
LT		 1756 struct file *filp,
1757 void __user *buffer,
1758 size_t *lenp, loff_t *ppos,
1759 unsigned long convmul,
1760 unsigned long convdiv)
1761{
1762#define TMPBUFLEN 21
1763 unsigned long *i, *min, *max, val;
1764 int vleft, first=1, neg;
1765 size_t len, left;
1766 char buf[TMPBUFLEN], *p;
1767 char __user *s = buffer;
1768
fcfbd547 1769 if (!data || !table->maxlen || !*lenp ||
1da177e4
LT		 1770 (*ppos && !write)) {
1771 *lenp = 0;
1772 return 0;
1773 }
1774
fcfbd547 1775 i = (unsigned long *) data;
1da177e4
LT		 1776 min = (unsigned long *) table->extra1;
1777 max = (unsigned long *) table->extra2;
1778 vleft = table->maxlen / sizeof(unsigned long);
1779 left = *lenp;
1780
1781 for (; left && vleft--; i++, min++, max++, first=0) {
1782 if (write) {
1783 while (left) {
1784 char c;
1785 if (get_user(c, s))
1786 return -EFAULT;
1787 if (!isspace(c))
1788 break;
1789 left--;
1790 s++;
1791 }
1792 if (!left)
1793 break;
1794 neg = 0;
1795 len = left;
1796 if (len > TMPBUFLEN-1)
1797 len = TMPBUFLEN-1;
1798 if (copy_from_user(buf, s, len))
1799 return -EFAULT;
1800 buf[len] = 0;
1801 p = buf;
1802 if (*p == '-' && left > 1) {
1803 neg = 1;
bd9b0bac 1804 p++;
1da177e4
LT		 1805 }
1806 if (*p < '0' || *p > '9')
1807 break;
1808 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1809 len = p-buf;
1810 if ((len < left) && *p && !isspace(*p))
1811 break;
1812 if (neg)
1813 val = -val;
1814 s += len;
1815 left -= len;
1816
1817 if(neg)
1818 continue;
1819 if ((min && val < *min) || (max && val > *max))
1820 continue;
1821 *i = val;
1822 } else {
1823 p = buf;
1824 if (!first)
1825 *p++ = '\t';
1826 sprintf(p, "%lu", convdiv * (*i) / convmul);
1827 len = strlen(buf);
1828 if (len > left)
1829 len = left;
1830 if(copy_to_user(s, buf, len))
1831 return -EFAULT;
1832 left -= len;
1833 s += len;
1834 }
1835 }
1836
1837 if (!write && !first && left) {
1838 if(put_user('\n', s))
1839 return -EFAULT;
1840 left--, s++;
1841 }
1842 if (write) {
1843 while (left) {
1844 char c;
1845 if (get_user(c, s++))
1846 return -EFAULT;
1847 if (!isspace(c))
1848 break;
1849 left--;
1850 }
1851 }
1852 if (write && first)
1853 return -EINVAL;
1854 *lenp -= left;
1855 *ppos += *lenp;
1856 return 0;
1857#undef TMPBUFLEN
1858}
1859
fcfbd547
KK		 1860static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1861 struct file *filp,
1862 void __user *buffer,
1863 size_t *lenp, loff_t *ppos,
1864 unsigned long convmul,
1865 unsigned long convdiv)
1866{
1867 return __do_proc_doulongvec_minmax(table->data, table, write,
1868 filp, buffer, lenp, ppos, convmul, convdiv);
1869}
1870
1da177e4
LT		 1871/**
1872 * proc_doulongvec_minmax - read a vector of long integers with min/max values
1873 * @table: the sysctl table
1874 * @write: %TRUE if this is a write to the sysctl file
1875 * @filp: the file structure
1876 * @buffer: the user buffer
1877 * @lenp: the size of the user buffer
1878 * @ppos: file position
1879 *
1880 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1881 * values from/to the user buffer, treated as an ASCII string.
1882 *
1883 * This routine will ensure the values are within the range specified by
1884 * table->extra1 (min) and table->extra2 (max).
1885 *
1886 * Returns 0 on success.
1887 */
1888int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1889 void __user *buffer, size_t *lenp, loff_t *ppos)
1890{
1891 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
1892}
1893
1894/**
1895 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1896 * @table: the sysctl table
1897 * @write: %TRUE if this is a write to the sysctl file
1898 * @filp: the file structure
1899 * @buffer: the user buffer
1900 * @lenp: the size of the user buffer
1901 * @ppos: file position
1902 *
1903 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1904 * values from/to the user buffer, treated as an ASCII string. The values
1905 * are treated as milliseconds, and converted to jiffies when they are stored.
1906 *
1907 * This routine will ensure the values are within the range specified by
1908 * table->extra1 (min) and table->extra2 (max).
1909 *
1910 * Returns 0 on success.
1911 */
1912int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
1913 struct file *filp,
1914 void __user *buffer,
1915 size_t *lenp, loff_t *ppos)
1916{
1917 return do_proc_doulongvec_minmax(table, write, filp, buffer,
1918 lenp, ppos, HZ, 1000l);
1919}
1920
1921
1922static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
1923 int *valp,
1924 int write, void *data)
1925{
1926 if (write) {
cba9f33d
BS		 1927 if (*lvalp > LONG_MAX / HZ)
1928 return 1;
1da177e4
LT		 1929 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1930 } else {
1931 int val = *valp;
1932 unsigned long lval;
1933 if (val < 0) {
1934 *negp = -1;
1935 lval = (unsigned long)-val;
1936 } else {
1937 *negp = 0;
1938 lval = (unsigned long)val;
1939 }
1940 *lvalp = lval / HZ;
1941 }
1942 return 0;
1943}
1944
1945static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
1946 int *valp,
1947 int write, void *data)
1948{
1949 if (write) {
cba9f33d
BS		 1950 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
1951 return 1;
1da177e4
LT		 1952 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
1953 } else {
1954 int val = *valp;
1955 unsigned long lval;
1956 if (val < 0) {
1957 *negp = -1;
1958 lval = (unsigned long)-val;
1959 } else {
1960 *negp = 0;
1961 lval = (unsigned long)val;
1962 }
1963 *lvalp = jiffies_to_clock_t(lval);
1964 }
1965 return 0;
1966}
1967
1968static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
1969 int *valp,
1970 int write, void *data)
1971{
1972 if (write) {
1973 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
1974 } else {
1975 int val = *valp;
1976 unsigned long lval;
1977 if (val < 0) {
1978 *negp = -1;
1979 lval = (unsigned long)-val;
1980 } else {
1981 *negp = 0;
1982 lval = (unsigned long)val;
1983 }
1984 *lvalp = jiffies_to_msecs(lval);
1985 }
1986 return 0;
1987}
1988
1989/**
1990 * proc_dointvec_jiffies - read a vector of integers as seconds
1991 * @table: the sysctl table
1992 * @write: %TRUE if this is a write to the sysctl file
1993 * @filp: the file structure
1994 * @buffer: the user buffer
1995 * @lenp: the size of the user buffer
1996 * @ppos: file position
1997 *
1998 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1999 * values from/to the user buffer, treated as an ASCII string.
2000 * The values read are assumed to be in seconds, and are converted into
2001 * jiffies.
2002 *
2003 * Returns 0 on success.
2004 */
2005int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2006 void __user *buffer, size_t *lenp, loff_t *ppos)
2007{
2008 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2009 do_proc_dointvec_jiffies_conv,NULL);
2010}
2011
2012/**
2013 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2014 * @table: the sysctl table
2015 * @write: %TRUE if this is a write to the sysctl file
2016 * @filp: the file structure
2017 * @buffer: the user buffer
2018 * @lenp: the size of the user buffer
1e5d5331 2019 * @ppos: pointer to the file position
1da177e4
LT		 2020 *
2021 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2022 * values from/to the user buffer, treated as an ASCII string.
2023 * The values read are assumed to be in 1/USER_HZ seconds, and
2024 * are converted into jiffies.
2025 *
2026 * Returns 0 on success.
2027 */
2028int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2029 void __user *buffer, size_t *lenp, loff_t *ppos)
2030{
2031 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2032 do_proc_dointvec_userhz_jiffies_conv,NULL);
2033}
2034
2035/**
2036 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2037 * @table: the sysctl table
2038 * @write: %TRUE if this is a write to the sysctl file
2039 * @filp: the file structure
2040 * @buffer: the user buffer
2041 * @lenp: the size of the user buffer
67be2dd1
MW		 2042 * @ppos: file position
2043 * @ppos: the current position in the file
1da177e4
LT		 2044 *
2045 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2046 * values from/to the user buffer, treated as an ASCII string.
2047 * The values read are assumed to be in 1/1000 seconds, and
2048 * are converted into jiffies.
2049 *
2050 * Returns 0 on success.
2051 */
2052int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2053 void __user *buffer, size_t *lenp, loff_t *ppos)
2054{
2055 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2056 do_proc_dointvec_ms_jiffies_conv, NULL);
2057}
2058
9ec52099
CLG		 2059static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
2060 void __user *buffer, size_t *lenp, loff_t *ppos)
2061{
2062 struct pid *new_pid;
2063 pid_t tmp;
2064 int r;
2065
2066 tmp = pid_nr(cad_pid);
2067
2068 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2069 lenp, ppos, NULL, NULL);
2070 if (r || !write)
2071 return r;
2072
2073 new_pid = find_get_pid(tmp);
2074 if (!new_pid)
2075 return -ESRCH;
2076
2077 put_pid(xchg(&cad_pid, new_pid));
2078 return 0;
2079}
2080
1da177e4
LT		 2081#else /* CONFIG_PROC_FS */
2082
2083int proc_dostring(ctl_table *table, int write, struct file *filp,
2084 void __user *buffer, size_t *lenp, loff_t *ppos)
2085{
2086 return -ENOSYS;
2087}
2088
1da177e4
LT		 2089int proc_dointvec(ctl_table *table, int write, struct file *filp,
2090 void __user *buffer, size_t *lenp, loff_t *ppos)
2091{
2092 return -ENOSYS;
2093}
2094
2095int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2096 void __user *buffer, size_t *lenp, loff_t *ppos)
2097{
2098 return -ENOSYS;
2099}
2100
2101int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2102 void __user *buffer, size_t *lenp, loff_t *ppos)
2103{
2104 return -ENOSYS;
2105}
2106
2107int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2108 void __user *buffer, size_t *lenp, loff_t *ppos)
2109{
2110 return -ENOSYS;
2111}
2112
2113int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2114 void __user *buffer, size_t *lenp, loff_t *ppos)
2115{
2116 return -ENOSYS;
2117}
2118
2119int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2120 void __user *buffer, size_t *lenp, loff_t *ppos)
2121{
2122 return -ENOSYS;
2123}
2124
2125int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2126 void __user *buffer, size_t *lenp, loff_t *ppos)
2127{
2128 return -ENOSYS;
2129}
2130
2131int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2132 struct file *filp,
2133 void __user *buffer,
2134 size_t *lenp, loff_t *ppos)
2135{
2136 return -ENOSYS;
2137}
2138
2139
2140#endif /* CONFIG_PROC_FS */
2141
2142
b89a8171 2143#ifdef CONFIG_SYSCTL_SYSCALL
1da177e4
LT		 2144/*
2145 * General sysctl support routines
2146 */
2147
2148/* The generic string strategy routine: */
2149int sysctl_string(ctl_table *table, int __user *name, int nlen,
2150 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2151 void __user *newval, size_t newlen)
1da177e4 2152{
1da177e4
LT		 2153 if (!table->data || !table->maxlen)
2154 return -ENOTDIR;
2155
2156 if (oldval && oldlenp) {
de9e007d
LT		 2157 size_t bufsize;
2158 if (get_user(bufsize, oldlenp))
1da177e4 2159 return -EFAULT;
de9e007d
LT		 2160 if (bufsize) {
2161 size_t len = strlen(table->data), copied;
2162
2163 /* This shouldn't trigger for a well-formed sysctl */
2164 if (len > table->maxlen)
1da177e4 2165 len = table->maxlen;
de9e007d
LT		 2166
2167 /* Copy up to a max of bufsize-1 bytes of the string */
2168 copied = (len >= bufsize) ? bufsize - 1 : len;
2169
2170 if (copy_to_user(oldval, table->data, copied) ||
2171 put_user(0, (char __user *)(oldval + copied)))
1da177e4 2172 return -EFAULT;
de9e007d 2173 if (put_user(len, oldlenp))
1da177e4
LT		 2174 return -EFAULT;
2175 }
2176 }
2177 if (newval && newlen) {
de9e007d 2178 size_t len = newlen;
1da177e4
LT		 2179 if (len > table->maxlen)
2180 len = table->maxlen;
2181 if(copy_from_user(table->data, newval, len))
2182 return -EFAULT;
2183 if (len == table->maxlen)
2184 len--;
2185 ((char *) table->data)[len] = 0;
2186 }
82c9df82 2187 return 1;
1da177e4
LT		 2188}
2189
2190/*
2191 * This function makes sure that all of the integers in the vector
2192 * are between the minimum and maximum values given in the arrays
2193 * table->extra1 and table->extra2, respectively.
2194 */
2195int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2196 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2197 void __user *newval, size_t newlen)
1da177e4
LT		 2198{
2199
2200 if (newval && newlen) {
2201 int __user *vec = (int __user *) newval;
2202 int *min = (int *) table->extra1;
2203 int *max = (int *) table->extra2;
2204 size_t length;
2205 int i;
2206
2207 if (newlen % sizeof(int) != 0)
2208 return -EINVAL;
2209
2210 if (!table->extra1 && !table->extra2)
2211 return 0;
2212
2213 if (newlen > table->maxlen)
2214 newlen = table->maxlen;
2215 length = newlen / sizeof(int);
2216
2217 for (i = 0; i < length; i++) {
2218 int value;
2219 if (get_user(value, vec + i))
2220 return -EFAULT;
2221 if (min && value < min[i])
2222 return -EINVAL;
2223 if (max && value > max[i])
2224 return -EINVAL;
2225 }
2226 }
2227 return 0;
2228}
2229
2230/* Strategy function to convert jiffies to seconds */
2231int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2232 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2233 void __user *newval, size_t newlen)
1da177e4 2234{
3ee75ac3 2235 if (oldval && oldlenp) {
1da177e4 2236 size_t olen;
3ee75ac3
AD		 2237
2238 if (get_user(olen, oldlenp))
2239 return -EFAULT;
2240 if (olen) {
2241 int val;
2242
2243 if (olen < sizeof(int))
2244 return -EINVAL;
2245
2246 val = *(int *)(table->data) / HZ;
2247 if (put_user(val, (int __user *)oldval))
2248 return -EFAULT;
2249 if (put_user(sizeof(int), oldlenp))
1da177e4 2250 return -EFAULT;
1da177e4 2251 }
1da177e4
LT		 2252 }
2253 if (newval && newlen) {
2254 int new;
2255 if (newlen != sizeof(int))
2256 return -EINVAL;
2257 if (get_user(new, (int __user *)newval))
2258 return -EFAULT;
2259 *(int *)(table->data) = new*HZ;
2260 }
2261 return 1;
2262}
2263
2264/* Strategy function to convert jiffies to seconds */
2265int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2266 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2267 void __user *newval, size_t newlen)
1da177e4 2268{
3ee75ac3 2269 if (oldval && oldlenp) {
1da177e4 2270 size_t olen;
3ee75ac3
AD		 2271
2272 if (get_user(olen, oldlenp))
2273 return -EFAULT;
2274 if (olen) {
2275 int val;
2276
2277 if (olen < sizeof(int))
2278 return -EINVAL;
2279
2280 val = jiffies_to_msecs(*(int *)(table->data));
2281 if (put_user(val, (int __user *)oldval))
2282 return -EFAULT;
2283 if (put_user(sizeof(int), oldlenp))
1da177e4 2284 return -EFAULT;
1da177e4 2285 }
1da177e4
LT		 2286 }
2287 if (newval && newlen) {
2288 int new;
2289 if (newlen != sizeof(int))
2290 return -EINVAL;
2291 if (get_user(new, (int __user *)newval))
2292 return -EFAULT;
2293 *(int *)(table->data) = msecs_to_jiffies(new);
2294 }
2295 return 1;
2296}
2297
c4b8b769 2298
c4b8b769 2299
b89a8171 2300#else /* CONFIG_SYSCTL_SYSCALL */
1da177e4
LT		 2301
2302
2303asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2304{
b89a8171 2305 static int msg_count;
0e009be8
EB		 2306 struct __sysctl_args tmp;
2307 int name[CTL_MAXNAME];
2308 int i;
2309
2310 /* Read in the sysctl name for better debug message logging */
2311 if (copy_from_user(&tmp, args, sizeof(tmp)))
2312 return -EFAULT;
2313 if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
2314 return -ENOTDIR;
2315 for (i = 0; i < tmp.nlen; i++)
2316 if (get_user(name[i], tmp.name + i))
2317 return -EFAULT;
2318
2319 /* Ignore accesses to kernel.version */
2320 if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2321 goto out;
b89a8171
EB		 2322
2323 if (msg_count < 5) {
2324 msg_count++;
2325 printk(KERN_INFO
2326 "warning: process `%s' used the removed sysctl "
0e009be8
EB		 2327 "system call with ", current->comm);
2328 for (i = 0; i < tmp.nlen; i++)
2329 printk("%d.", name[i]);
2330 printk("\n");
b89a8171 2331 }
0e009be8 2332out:
1da177e4
LT		 2333 return -ENOSYS;
2334}
2335
2336int sysctl_string(ctl_table *table, int __user *name, int nlen,
2337 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2338 void __user *newval, size_t newlen)
1da177e4
LT		 2339{
2340 return -ENOSYS;
2341}
2342
2343int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2344 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2345 void __user *newval, size_t newlen)
1da177e4
LT		 2346{
2347 return -ENOSYS;
2348}
2349
2350int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2351 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2352 void __user *newval, size_t newlen)
1da177e4
LT		 2353{
2354 return -ENOSYS;
2355}
2356
2357int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2358 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2359 void __user *newval, size_t newlen)
1da177e4
LT		 2360{
2361 return -ENOSYS;
2362}
2363
b89a8171 2364#endif /* CONFIG_SYSCTL_SYSCALL */
1da177e4
LT		 2365
2366/*
2367 * No sense putting this after each symbol definition, twice,
2368 * exception granted :-)
2369 */
2370EXPORT_SYMBOL(proc_dointvec);
2371EXPORT_SYMBOL(proc_dointvec_jiffies);
2372EXPORT_SYMBOL(proc_dointvec_minmax);
2373EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2374EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2375EXPORT_SYMBOL(proc_dostring);
2376EXPORT_SYMBOL(proc_doulongvec_minmax);
2377EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2378EXPORT_SYMBOL(register_sysctl_table);
2379EXPORT_SYMBOL(sysctl_intvec);
2380EXPORT_SYMBOL(sysctl_jiffies);
2381EXPORT_SYMBOL(sysctl_ms_jiffies);
2382EXPORT_SYMBOL(sysctl_string);
2383EXPORT_SYMBOL(unregister_sysctl_table);
Linux 6.x block layer and io_uring tree(s)