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[PATCH] sysctl: move SYSV IPC sysctls to their own file
[mirror_ubuntu-zesty-kernel.git] / kernel / sysctl.c
CommitLineData
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;
1da177e4 79
1da177e4
LT
80/* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
81static int maxolduid = 65535;
82static int minolduid;
8ad4b1fb 83static int min_percpu_pagelist_fract = 8;
1da177e4
LT
84
85static int ngroups_max = NGROUPS_MAX;
86
87#ifdef CONFIG_KMOD
88extern char modprobe_path[];
89#endif
1da177e4
LT
90#ifdef CONFIG_CHR_DEV_SG
91extern int sg_big_buff;
92#endif
1da177e4
LT
93
94#ifdef __sparc__
95extern char reboot_command [];
96extern int stop_a_enabled;
97extern int scons_pwroff;
98#endif
99
100#ifdef __hppa__
101extern int pwrsw_enabled;
102extern int unaligned_enabled;
103#endif
104
347a8dc3 105#ifdef CONFIG_S390
1da177e4
LT
106#ifdef CONFIG_MATHEMU
107extern int sysctl_ieee_emulation_warnings;
108#endif
109extern int sysctl_userprocess_debug;
951f22d5 110extern int spin_retry;
1da177e4
LT
111#endif
112
113extern int sysctl_hz_timer;
114
115#ifdef CONFIG_BSD_PROCESS_ACCT
116extern int acct_parm[];
117#endif
118
d2b176ed
JS
119#ifdef CONFIG_IA64
120extern int no_unaligned_warning;
121#endif
122
23f78d4a
IM
123#ifdef CONFIG_RT_MUTEXES
124extern int max_lock_depth;
125#endif
126
b89a8171
EB
127#ifdef CONFIG_SYSCTL_SYSCALL
128static int parse_table(int __user *, int, void __user *, size_t __user *,
1f29bcd7 129 void __user *, size_t, ctl_table *);
b89a8171
EB
130#endif
131
6b49a257 132
d6f8ff73 133#ifdef CONFIG_PROC_SYSCTL
9ec52099
CLG
134static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
135 void __user *buffer, size_t *lenp, loff_t *ppos);
34f5a398
TT
136static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
137 void __user *buffer, size_t *lenp, loff_t *ppos);
d6f8ff73 138#endif
9ec52099 139
1da177e4
LT
140static ctl_table root_table[];
141static struct ctl_table_header root_table_header =
142 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
143
144static ctl_table kern_table[];
145static ctl_table vm_table[];
1da177e4
LT
146static ctl_table fs_table[];
147static ctl_table debug_table[];
148static ctl_table dev_table[];
149extern ctl_table random_table[];
150#ifdef CONFIG_UNIX98_PTYS
151extern ctl_table pty_table[];
152#endif
2d9048e2 153#ifdef CONFIG_INOTIFY_USER
0399cb08
RL
154extern ctl_table inotify_table[];
155#endif
1da177e4
LT
156
157#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
158int sysctl_legacy_va_layout;
159#endif
160
9bc9a6bd 161
1da177e4
LT
162/* /proc declarations: */
163
b89a8171 164#ifdef CONFIG_PROC_SYSCTL
1da177e4
LT
165
166static ssize_t proc_readsys(struct file *, char __user *, size_t, loff_t *);
167static ssize_t proc_writesys(struct file *, const char __user *, size_t, loff_t *);
168static int proc_opensys(struct inode *, struct file *);
169
15ad7cdc 170const struct file_operations proc_sys_file_operations = {
1da177e4
LT
171 .open = proc_opensys,
172 .read = proc_readsys,
173 .write = proc_writesys,
174};
175
176extern struct proc_dir_entry *proc_sys_root;
177
330d57fb 178static void register_proc_table(ctl_table *, struct proc_dir_entry *, void *);
1da177e4
LT
179static void unregister_proc_table(ctl_table *, struct proc_dir_entry *);
180#endif
181
182/* The default sysctl tables: */
183
184static ctl_table root_table[] = {
185 {
186 .ctl_name = CTL_KERN,
187 .procname = "kernel",
188 .mode = 0555,
189 .child = kern_table,
190 },
191 {
192 .ctl_name = CTL_VM,
193 .procname = "vm",
194 .mode = 0555,
195 .child = vm_table,
196 },
197#ifdef CONFIG_NET
198 {
199 .ctl_name = CTL_NET,
200 .procname = "net",
201 .mode = 0555,
202 .child = net_table,
203 },
204#endif
1da177e4
LT
205 {
206 .ctl_name = CTL_FS,
207 .procname = "fs",
208 .mode = 0555,
209 .child = fs_table,
210 },
211 {
212 .ctl_name = CTL_DEBUG,
213 .procname = "debug",
214 .mode = 0555,
215 .child = debug_table,
216 },
217 {
218 .ctl_name = CTL_DEV,
219 .procname = "dev",
220 .mode = 0555,
221 .child = dev_table,
222 },
0eeca283 223
1da177e4
LT
224 { .ctl_name = 0 }
225};
226
227static ctl_table kern_table[] = {
1da177e4
LT
228 {
229 .ctl_name = KERN_PANIC,
230 .procname = "panic",
231 .data = &panic_timeout,
232 .maxlen = sizeof(int),
233 .mode = 0644,
234 .proc_handler = &proc_dointvec,
235 },
236 {
237 .ctl_name = KERN_CORE_USES_PID,
238 .procname = "core_uses_pid",
239 .data = &core_uses_pid,
240 .maxlen = sizeof(int),
241 .mode = 0644,
242 .proc_handler = &proc_dointvec,
243 },
244 {
245 .ctl_name = KERN_CORE_PATTERN,
246 .procname = "core_pattern",
247 .data = core_pattern,
d025c9db 248 .maxlen = 128,
1da177e4
LT
249 .mode = 0644,
250 .proc_handler = &proc_dostring,
251 .strategy = &sysctl_string,
252 },
34f5a398 253#ifdef CONFIG_PROC_SYSCTL
1da177e4
LT
254 {
255 .ctl_name = KERN_TAINTED,
256 .procname = "tainted",
257 .data = &tainted,
258 .maxlen = sizeof(int),
34f5a398
TT
259 .mode = 0644,
260 .proc_handler = &proc_dointvec_taint,
1da177e4 261 },
34f5a398 262#endif
1da177e4
LT
263 {
264 .ctl_name = KERN_CAP_BSET,
265 .procname = "cap-bound",
266 .data = &cap_bset,
267 .maxlen = sizeof(kernel_cap_t),
268 .mode = 0600,
269 .proc_handler = &proc_dointvec_bset,
270 },
271#ifdef CONFIG_BLK_DEV_INITRD
272 {
273 .ctl_name = KERN_REALROOTDEV,
274 .procname = "real-root-dev",
275 .data = &real_root_dev,
276 .maxlen = sizeof(int),
277 .mode = 0644,
278 .proc_handler = &proc_dointvec,
279 },
280#endif
281#ifdef __sparc__
282 {
283 .ctl_name = KERN_SPARC_REBOOT,
284 .procname = "reboot-cmd",
285 .data = reboot_command,
286 .maxlen = 256,
287 .mode = 0644,
288 .proc_handler = &proc_dostring,
289 .strategy = &sysctl_string,
290 },
291 {
292 .ctl_name = KERN_SPARC_STOP_A,
293 .procname = "stop-a",
294 .data = &stop_a_enabled,
295 .maxlen = sizeof (int),
296 .mode = 0644,
297 .proc_handler = &proc_dointvec,
298 },
299 {
300 .ctl_name = KERN_SPARC_SCONS_PWROFF,
301 .procname = "scons-poweroff",
302 .data = &scons_pwroff,
303 .maxlen = sizeof (int),
304 .mode = 0644,
305 .proc_handler = &proc_dointvec,
306 },
307#endif
308#ifdef __hppa__
309 {
310 .ctl_name = KERN_HPPA_PWRSW,
311 .procname = "soft-power",
312 .data = &pwrsw_enabled,
313 .maxlen = sizeof (int),
314 .mode = 0644,
315 .proc_handler = &proc_dointvec,
316 },
317 {
318 .ctl_name = KERN_HPPA_UNALIGNED,
319 .procname = "unaligned-trap",
320 .data = &unaligned_enabled,
321 .maxlen = sizeof (int),
322 .mode = 0644,
323 .proc_handler = &proc_dointvec,
324 },
325#endif
326 {
327 .ctl_name = KERN_CTLALTDEL,
328 .procname = "ctrl-alt-del",
329 .data = &C_A_D,
330 .maxlen = sizeof(int),
331 .mode = 0644,
332 .proc_handler = &proc_dointvec,
333 },
334 {
335 .ctl_name = KERN_PRINTK,
336 .procname = "printk",
337 .data = &console_loglevel,
338 .maxlen = 4*sizeof(int),
339 .mode = 0644,
340 .proc_handler = &proc_dointvec,
341 },
342#ifdef CONFIG_KMOD
343 {
344 .ctl_name = KERN_MODPROBE,
345 .procname = "modprobe",
346 .data = &modprobe_path,
347 .maxlen = KMOD_PATH_LEN,
348 .mode = 0644,
349 .proc_handler = &proc_dostring,
350 .strategy = &sysctl_string,
351 },
352#endif
57ae2508 353#if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
1da177e4
LT
354 {
355 .ctl_name = KERN_HOTPLUG,
356 .procname = "hotplug",
312c004d
KS
357 .data = &uevent_helper,
358 .maxlen = UEVENT_HELPER_PATH_LEN,
1da177e4
LT
359 .mode = 0644,
360 .proc_handler = &proc_dostring,
361 .strategy = &sysctl_string,
362 },
363#endif
364#ifdef CONFIG_CHR_DEV_SG
365 {
366 .ctl_name = KERN_SG_BIG_BUFF,
367 .procname = "sg-big-buff",
368 .data = &sg_big_buff,
369 .maxlen = sizeof (int),
370 .mode = 0444,
371 .proc_handler = &proc_dointvec,
372 },
373#endif
374#ifdef CONFIG_BSD_PROCESS_ACCT
375 {
376 .ctl_name = KERN_ACCT,
377 .procname = "acct",
378 .data = &acct_parm,
379 .maxlen = 3*sizeof(int),
380 .mode = 0644,
381 .proc_handler = &proc_dointvec,
382 },
383#endif
1da177e4
LT
384#ifdef CONFIG_MAGIC_SYSRQ
385 {
386 .ctl_name = KERN_SYSRQ,
387 .procname = "sysrq",
5d6f647f 388 .data = &__sysrq_enabled,
1da177e4
LT
389 .maxlen = sizeof (int),
390 .mode = 0644,
391 .proc_handler = &proc_dointvec,
392 },
393#endif
d6f8ff73 394#ifdef CONFIG_PROC_SYSCTL
1da177e4
LT
395 {
396 .ctl_name = KERN_CADPID,
397 .procname = "cad_pid",
9ec52099 398 .data = NULL,
1da177e4
LT
399 .maxlen = sizeof (int),
400 .mode = 0600,
9ec52099 401 .proc_handler = &proc_do_cad_pid,
1da177e4 402 },
d6f8ff73 403#endif
1da177e4
LT
404 {
405 .ctl_name = KERN_MAX_THREADS,
406 .procname = "threads-max",
407 .data = &max_threads,
408 .maxlen = sizeof(int),
409 .mode = 0644,
410 .proc_handler = &proc_dointvec,
411 },
412 {
413 .ctl_name = KERN_RANDOM,
414 .procname = "random",
415 .mode = 0555,
416 .child = random_table,
417 },
418#ifdef CONFIG_UNIX98_PTYS
419 {
420 .ctl_name = KERN_PTY,
421 .procname = "pty",
422 .mode = 0555,
423 .child = pty_table,
424 },
425#endif
426 {
427 .ctl_name = KERN_OVERFLOWUID,
428 .procname = "overflowuid",
429 .data = &overflowuid,
430 .maxlen = sizeof(int),
431 .mode = 0644,
432 .proc_handler = &proc_dointvec_minmax,
433 .strategy = &sysctl_intvec,
434 .extra1 = &minolduid,
435 .extra2 = &maxolduid,
436 },
437 {
438 .ctl_name = KERN_OVERFLOWGID,
439 .procname = "overflowgid",
440 .data = &overflowgid,
441 .maxlen = sizeof(int),
442 .mode = 0644,
443 .proc_handler = &proc_dointvec_minmax,
444 .strategy = &sysctl_intvec,
445 .extra1 = &minolduid,
446 .extra2 = &maxolduid,
447 },
347a8dc3 448#ifdef CONFIG_S390
1da177e4
LT
449#ifdef CONFIG_MATHEMU
450 {
451 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
452 .procname = "ieee_emulation_warnings",
453 .data = &sysctl_ieee_emulation_warnings,
454 .maxlen = sizeof(int),
455 .mode = 0644,
456 .proc_handler = &proc_dointvec,
457 },
458#endif
459#ifdef CONFIG_NO_IDLE_HZ
460 {
461 .ctl_name = KERN_HZ_TIMER,
462 .procname = "hz_timer",
463 .data = &sysctl_hz_timer,
464 .maxlen = sizeof(int),
465 .mode = 0644,
466 .proc_handler = &proc_dointvec,
467 },
468#endif
469 {
470 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
471 .procname = "userprocess_debug",
472 .data = &sysctl_userprocess_debug,
473 .maxlen = sizeof(int),
474 .mode = 0644,
475 .proc_handler = &proc_dointvec,
476 },
477#endif
478 {
479 .ctl_name = KERN_PIDMAX,
480 .procname = "pid_max",
481 .data = &pid_max,
482 .maxlen = sizeof (int),
483 .mode = 0644,
484 .proc_handler = &proc_dointvec_minmax,
485 .strategy = sysctl_intvec,
486 .extra1 = &pid_max_min,
487 .extra2 = &pid_max_max,
488 },
489 {
490 .ctl_name = KERN_PANIC_ON_OOPS,
491 .procname = "panic_on_oops",
492 .data = &panic_on_oops,
493 .maxlen = sizeof(int),
494 .mode = 0644,
495 .proc_handler = &proc_dointvec,
496 },
497 {
498 .ctl_name = KERN_PRINTK_RATELIMIT,
499 .procname = "printk_ratelimit",
500 .data = &printk_ratelimit_jiffies,
501 .maxlen = sizeof(int),
502 .mode = 0644,
503 .proc_handler = &proc_dointvec_jiffies,
504 .strategy = &sysctl_jiffies,
505 },
506 {
507 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
508 .procname = "printk_ratelimit_burst",
509 .data = &printk_ratelimit_burst,
510 .maxlen = sizeof(int),
511 .mode = 0644,
512 .proc_handler = &proc_dointvec,
513 },
514 {
515 .ctl_name = KERN_NGROUPS_MAX,
516 .procname = "ngroups_max",
517 .data = &ngroups_max,
518 .maxlen = sizeof (int),
519 .mode = 0444,
520 .proc_handler = &proc_dointvec,
521 },
522#if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
523 {
524 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
525 .procname = "unknown_nmi_panic",
526 .data = &unknown_nmi_panic,
527 .maxlen = sizeof (int),
528 .mode = 0644,
2fbe7b25 529 .proc_handler = &proc_dointvec,
1da177e4 530 },
407984f1
DZ
531 {
532 .ctl_name = KERN_NMI_WATCHDOG,
533 .procname = "nmi_watchdog",
534 .data = &nmi_watchdog_enabled,
535 .maxlen = sizeof (int),
536 .mode = 0644,
537 .proc_handler = &proc_nmi_enabled,
1da177e4
LT
538 },
539#endif
540#if defined(CONFIG_X86)
8da5adda
DZ
541 {
542 .ctl_name = KERN_PANIC_ON_NMI,
543 .procname = "panic_on_unrecovered_nmi",
544 .data = &panic_on_unrecovered_nmi,
545 .maxlen = sizeof(int),
546 .mode = 0644,
547 .proc_handler = &proc_dointvec,
548 },
1da177e4
LT
549 {
550 .ctl_name = KERN_BOOTLOADER_TYPE,
551 .procname = "bootloader_type",
552 .data = &bootloader_type,
553 .maxlen = sizeof (int),
554 .mode = 0444,
555 .proc_handler = &proc_dointvec,
556 },
0741f4d2
CE
557 {
558 .ctl_name = CTL_UNNUMBERED,
559 .procname = "kstack_depth_to_print",
560 .data = &kstack_depth_to_print,
561 .maxlen = sizeof(int),
562 .mode = 0644,
563 .proc_handler = &proc_dointvec,
564 },
1da177e4 565#endif
7a9166e3 566#if defined(CONFIG_MMU)
1da177e4
LT
567 {
568 .ctl_name = KERN_RANDOMIZE,
569 .procname = "randomize_va_space",
570 .data = &randomize_va_space,
571 .maxlen = sizeof(int),
572 .mode = 0644,
573 .proc_handler = &proc_dointvec,
574 },
7a9166e3 575#endif
0152fb37 576#if defined(CONFIG_S390) && defined(CONFIG_SMP)
951f22d5
MS
577 {
578 .ctl_name = KERN_SPIN_RETRY,
579 .procname = "spin_retry",
580 .data = &spin_retry,
581 .maxlen = sizeof (int),
582 .mode = 0644,
583 .proc_handler = &proc_dointvec,
584 },
c255d844
PM
585#endif
586#ifdef CONFIG_ACPI_SLEEP
587 {
588 .ctl_name = KERN_ACPI_VIDEO_FLAGS,
589 .procname = "acpi_video_flags",
590 .data = &acpi_video_flags,
591 .maxlen = sizeof (unsigned long),
592 .mode = 0644,
7f99f06f 593 .proc_handler = &proc_doulongvec_minmax,
c255d844 594 },
d2b176ed
JS
595#endif
596#ifdef CONFIG_IA64
597 {
598 .ctl_name = KERN_IA64_UNALIGNED,
599 .procname = "ignore-unaligned-usertrap",
600 .data = &no_unaligned_warning,
601 .maxlen = sizeof (int),
602 .mode = 0644,
603 .proc_handler = &proc_dointvec,
604 },
bebfa101
AK
605#endif
606#ifdef CONFIG_COMPAT
607 {
608 .ctl_name = KERN_COMPAT_LOG,
609 .procname = "compat-log",
610 .data = &compat_log,
611 .maxlen = sizeof (int),
612 .mode = 0644,
613 .proc_handler = &proc_dointvec,
614 },
951f22d5 615#endif
23f78d4a
IM
616#ifdef CONFIG_RT_MUTEXES
617 {
618 .ctl_name = KERN_MAX_LOCK_DEPTH,
619 .procname = "max_lock_depth",
620 .data = &max_lock_depth,
621 .maxlen = sizeof(int),
622 .mode = 0644,
623 .proc_handler = &proc_dointvec,
624 },
625#endif
626
1da177e4
LT
627 { .ctl_name = 0 }
628};
629
630/* Constants for minimum and maximum testing in vm_table.
631 We use these as one-element integer vectors. */
632static int zero;
633static int one_hundred = 100;
634
635
636static ctl_table vm_table[] = {
637 {
638 .ctl_name = VM_OVERCOMMIT_MEMORY,
639 .procname = "overcommit_memory",
640 .data = &sysctl_overcommit_memory,
641 .maxlen = sizeof(sysctl_overcommit_memory),
642 .mode = 0644,
643 .proc_handler = &proc_dointvec,
644 },
fadd8fbd
KH
645 {
646 .ctl_name = VM_PANIC_ON_OOM,
647 .procname = "panic_on_oom",
648 .data = &sysctl_panic_on_oom,
649 .maxlen = sizeof(sysctl_panic_on_oom),
650 .mode = 0644,
651 .proc_handler = &proc_dointvec,
652 },
1da177e4
LT
653 {
654 .ctl_name = VM_OVERCOMMIT_RATIO,
655 .procname = "overcommit_ratio",
656 .data = &sysctl_overcommit_ratio,
657 .maxlen = sizeof(sysctl_overcommit_ratio),
658 .mode = 0644,
659 .proc_handler = &proc_dointvec,
660 },
661 {
662 .ctl_name = VM_PAGE_CLUSTER,
663 .procname = "page-cluster",
664 .data = &page_cluster,
665 .maxlen = sizeof(int),
666 .mode = 0644,
667 .proc_handler = &proc_dointvec,
668 },
669 {
670 .ctl_name = VM_DIRTY_BACKGROUND,
671 .procname = "dirty_background_ratio",
672 .data = &dirty_background_ratio,
673 .maxlen = sizeof(dirty_background_ratio),
674 .mode = 0644,
675 .proc_handler = &proc_dointvec_minmax,
676 .strategy = &sysctl_intvec,
677 .extra1 = &zero,
678 .extra2 = &one_hundred,
679 },
680 {
681 .ctl_name = VM_DIRTY_RATIO,
682 .procname = "dirty_ratio",
683 .data = &vm_dirty_ratio,
684 .maxlen = sizeof(vm_dirty_ratio),
685 .mode = 0644,
686 .proc_handler = &proc_dointvec_minmax,
687 .strategy = &sysctl_intvec,
688 .extra1 = &zero,
689 .extra2 = &one_hundred,
690 },
691 {
692 .ctl_name = VM_DIRTY_WB_CS,
693 .procname = "dirty_writeback_centisecs",
f6ef9438
BS
694 .data = &dirty_writeback_interval,
695 .maxlen = sizeof(dirty_writeback_interval),
1da177e4
LT
696 .mode = 0644,
697 .proc_handler = &dirty_writeback_centisecs_handler,
698 },
699 {
700 .ctl_name = VM_DIRTY_EXPIRE_CS,
701 .procname = "dirty_expire_centisecs",
f6ef9438
BS
702 .data = &dirty_expire_interval,
703 .maxlen = sizeof(dirty_expire_interval),
1da177e4 704 .mode = 0644,
f6ef9438 705 .proc_handler = &proc_dointvec_userhz_jiffies,
1da177e4
LT
706 },
707 {
708 .ctl_name = VM_NR_PDFLUSH_THREADS,
709 .procname = "nr_pdflush_threads",
710 .data = &nr_pdflush_threads,
711 .maxlen = sizeof nr_pdflush_threads,
712 .mode = 0444 /* read-only*/,
713 .proc_handler = &proc_dointvec,
714 },
715 {
716 .ctl_name = VM_SWAPPINESS,
717 .procname = "swappiness",
718 .data = &vm_swappiness,
719 .maxlen = sizeof(vm_swappiness),
720 .mode = 0644,
721 .proc_handler = &proc_dointvec_minmax,
722 .strategy = &sysctl_intvec,
723 .extra1 = &zero,
724 .extra2 = &one_hundred,
725 },
726#ifdef CONFIG_HUGETLB_PAGE
727 {
728 .ctl_name = VM_HUGETLB_PAGES,
729 .procname = "nr_hugepages",
730 .data = &max_huge_pages,
731 .maxlen = sizeof(unsigned long),
732 .mode = 0644,
733 .proc_handler = &hugetlb_sysctl_handler,
734 .extra1 = (void *)&hugetlb_zero,
735 .extra2 = (void *)&hugetlb_infinity,
736 },
737 {
738 .ctl_name = VM_HUGETLB_GROUP,
739 .procname = "hugetlb_shm_group",
740 .data = &sysctl_hugetlb_shm_group,
741 .maxlen = sizeof(gid_t),
742 .mode = 0644,
743 .proc_handler = &proc_dointvec,
744 },
745#endif
746 {
747 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
748 .procname = "lowmem_reserve_ratio",
749 .data = &sysctl_lowmem_reserve_ratio,
750 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
751 .mode = 0644,
752 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
753 .strategy = &sysctl_intvec,
754 },
9d0243bc
AM
755 {
756 .ctl_name = VM_DROP_PAGECACHE,
757 .procname = "drop_caches",
758 .data = &sysctl_drop_caches,
759 .maxlen = sizeof(int),
760 .mode = 0644,
761 .proc_handler = drop_caches_sysctl_handler,
762 .strategy = &sysctl_intvec,
763 },
1da177e4
LT
764 {
765 .ctl_name = VM_MIN_FREE_KBYTES,
766 .procname = "min_free_kbytes",
767 .data = &min_free_kbytes,
768 .maxlen = sizeof(min_free_kbytes),
769 .mode = 0644,
770 .proc_handler = &min_free_kbytes_sysctl_handler,
771 .strategy = &sysctl_intvec,
772 .extra1 = &zero,
773 },
8ad4b1fb
RS
774 {
775 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
776 .procname = "percpu_pagelist_fraction",
777 .data = &percpu_pagelist_fraction,
778 .maxlen = sizeof(percpu_pagelist_fraction),
779 .mode = 0644,
780 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
781 .strategy = &sysctl_intvec,
782 .extra1 = &min_percpu_pagelist_fract,
783 },
1da177e4
LT
784#ifdef CONFIG_MMU
785 {
786 .ctl_name = VM_MAX_MAP_COUNT,
787 .procname = "max_map_count",
788 .data = &sysctl_max_map_count,
789 .maxlen = sizeof(sysctl_max_map_count),
790 .mode = 0644,
791 .proc_handler = &proc_dointvec
792 },
793#endif
794 {
795 .ctl_name = VM_LAPTOP_MODE,
796 .procname = "laptop_mode",
797 .data = &laptop_mode,
798 .maxlen = sizeof(laptop_mode),
799 .mode = 0644,
ed5b43f1
BS
800 .proc_handler = &proc_dointvec_jiffies,
801 .strategy = &sysctl_jiffies,
1da177e4
LT
802 },
803 {
804 .ctl_name = VM_BLOCK_DUMP,
805 .procname = "block_dump",
806 .data = &block_dump,
807 .maxlen = sizeof(block_dump),
808 .mode = 0644,
809 .proc_handler = &proc_dointvec,
810 .strategy = &sysctl_intvec,
811 .extra1 = &zero,
812 },
813 {
814 .ctl_name = VM_VFS_CACHE_PRESSURE,
815 .procname = "vfs_cache_pressure",
816 .data = &sysctl_vfs_cache_pressure,
817 .maxlen = sizeof(sysctl_vfs_cache_pressure),
818 .mode = 0644,
819 .proc_handler = &proc_dointvec,
820 .strategy = &sysctl_intvec,
821 .extra1 = &zero,
822 },
823#ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
824 {
825 .ctl_name = VM_LEGACY_VA_LAYOUT,
826 .procname = "legacy_va_layout",
827 .data = &sysctl_legacy_va_layout,
828 .maxlen = sizeof(sysctl_legacy_va_layout),
829 .mode = 0644,
830 .proc_handler = &proc_dointvec,
831 .strategy = &sysctl_intvec,
832 .extra1 = &zero,
833 },
834#endif
1743660b
CL
835#ifdef CONFIG_NUMA
836 {
837 .ctl_name = VM_ZONE_RECLAIM_MODE,
838 .procname = "zone_reclaim_mode",
839 .data = &zone_reclaim_mode,
840 .maxlen = sizeof(zone_reclaim_mode),
841 .mode = 0644,
842 .proc_handler = &proc_dointvec,
c84db23c
CL
843 .strategy = &sysctl_intvec,
844 .extra1 = &zero,
1743660b 845 },
9614634f
CL
846 {
847 .ctl_name = VM_MIN_UNMAPPED,
848 .procname = "min_unmapped_ratio",
849 .data = &sysctl_min_unmapped_ratio,
850 .maxlen = sizeof(sysctl_min_unmapped_ratio),
851 .mode = 0644,
852 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
853 .strategy = &sysctl_intvec,
854 .extra1 = &zero,
855 .extra2 = &one_hundred,
856 },
0ff38490
CL
857 {
858 .ctl_name = VM_MIN_SLAB,
859 .procname = "min_slab_ratio",
860 .data = &sysctl_min_slab_ratio,
861 .maxlen = sizeof(sysctl_min_slab_ratio),
862 .mode = 0644,
863 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
864 .strategy = &sysctl_intvec,
865 .extra1 = &zero,
866 .extra2 = &one_hundred,
867 },
e6e5494c
IM
868#endif
869#ifdef CONFIG_X86_32
870 {
871 .ctl_name = VM_VDSO_ENABLED,
872 .procname = "vdso_enabled",
873 .data = &vdso_enabled,
874 .maxlen = sizeof(vdso_enabled),
875 .mode = 0644,
876 .proc_handler = &proc_dointvec,
877 .strategy = &sysctl_intvec,
878 .extra1 = &zero,
879 },
1da177e4
LT
880#endif
881 { .ctl_name = 0 }
882};
883
1da177e4
LT
884static ctl_table fs_table[] = {
885 {
886 .ctl_name = FS_NRINODE,
887 .procname = "inode-nr",
888 .data = &inodes_stat,
889 .maxlen = 2*sizeof(int),
890 .mode = 0444,
891 .proc_handler = &proc_dointvec,
892 },
893 {
894 .ctl_name = FS_STATINODE,
895 .procname = "inode-state",
896 .data = &inodes_stat,
897 .maxlen = 7*sizeof(int),
898 .mode = 0444,
899 .proc_handler = &proc_dointvec,
900 },
901 {
902 .ctl_name = FS_NRFILE,
903 .procname = "file-nr",
904 .data = &files_stat,
905 .maxlen = 3*sizeof(int),
906 .mode = 0444,
529bf6be 907 .proc_handler = &proc_nr_files,
1da177e4
LT
908 },
909 {
910 .ctl_name = FS_MAXFILE,
911 .procname = "file-max",
912 .data = &files_stat.max_files,
913 .maxlen = sizeof(int),
914 .mode = 0644,
915 .proc_handler = &proc_dointvec,
916 },
917 {
918 .ctl_name = FS_DENTRY,
919 .procname = "dentry-state",
920 .data = &dentry_stat,
921 .maxlen = 6*sizeof(int),
922 .mode = 0444,
923 .proc_handler = &proc_dointvec,
924 },
925 {
926 .ctl_name = FS_OVERFLOWUID,
927 .procname = "overflowuid",
928 .data = &fs_overflowuid,
929 .maxlen = sizeof(int),
930 .mode = 0644,
931 .proc_handler = &proc_dointvec_minmax,
932 .strategy = &sysctl_intvec,
933 .extra1 = &minolduid,
934 .extra2 = &maxolduid,
935 },
936 {
937 .ctl_name = FS_OVERFLOWGID,
938 .procname = "overflowgid",
939 .data = &fs_overflowgid,
940 .maxlen = sizeof(int),
941 .mode = 0644,
942 .proc_handler = &proc_dointvec_minmax,
943 .strategy = &sysctl_intvec,
944 .extra1 = &minolduid,
945 .extra2 = &maxolduid,
946 },
947 {
948 .ctl_name = FS_LEASES,
949 .procname = "leases-enable",
950 .data = &leases_enable,
951 .maxlen = sizeof(int),
952 .mode = 0644,
953 .proc_handler = &proc_dointvec,
954 },
955#ifdef CONFIG_DNOTIFY
956 {
957 .ctl_name = FS_DIR_NOTIFY,
958 .procname = "dir-notify-enable",
959 .data = &dir_notify_enable,
960 .maxlen = sizeof(int),
961 .mode = 0644,
962 .proc_handler = &proc_dointvec,
963 },
964#endif
965#ifdef CONFIG_MMU
966 {
967 .ctl_name = FS_LEASE_TIME,
968 .procname = "lease-break-time",
969 .data = &lease_break_time,
970 .maxlen = sizeof(int),
971 .mode = 0644,
972 .proc_handler = &proc_dointvec,
973 },
974 {
975 .ctl_name = FS_AIO_NR,
976 .procname = "aio-nr",
977 .data = &aio_nr,
978 .maxlen = sizeof(aio_nr),
979 .mode = 0444,
d55b5fda 980 .proc_handler = &proc_doulongvec_minmax,
1da177e4
LT
981 },
982 {
983 .ctl_name = FS_AIO_MAX_NR,
984 .procname = "aio-max-nr",
985 .data = &aio_max_nr,
986 .maxlen = sizeof(aio_max_nr),
987 .mode = 0644,
d55b5fda 988 .proc_handler = &proc_doulongvec_minmax,
1da177e4 989 },
2d9048e2 990#ifdef CONFIG_INOTIFY_USER
0399cb08
RL
991 {
992 .ctl_name = FS_INOTIFY,
993 .procname = "inotify",
994 .mode = 0555,
995 .child = inotify_table,
996 },
997#endif
1da177e4 998#endif
d6e71144
AC
999 {
1000 .ctl_name = KERN_SETUID_DUMPABLE,
1001 .procname = "suid_dumpable",
1002 .data = &suid_dumpable,
1003 .maxlen = sizeof(int),
1004 .mode = 0644,
1005 .proc_handler = &proc_dointvec,
1006 },
1da177e4
LT
1007 { .ctl_name = 0 }
1008};
1009
1010static ctl_table debug_table[] = {
1011 { .ctl_name = 0 }
1012};
1013
1014static ctl_table dev_table[] = {
1015 { .ctl_name = 0 }
0eeca283 1016};
1da177e4 1017
330d57fb
AV
1018static DEFINE_SPINLOCK(sysctl_lock);
1019
1020/* called under sysctl_lock */
1021static int use_table(struct ctl_table_header *p)
1022{
1023 if (unlikely(p->unregistering))
1024 return 0;
1025 p->used++;
1026 return 1;
1027}
1028
1029/* called under sysctl_lock */
1030static void unuse_table(struct ctl_table_header *p)
1031{
1032 if (!--p->used)
1033 if (unlikely(p->unregistering))
1034 complete(p->unregistering);
1035}
1036
1037/* called under sysctl_lock, will reacquire if has to wait */
1038static void start_unregistering(struct ctl_table_header *p)
1039{
1040 /*
1041 * if p->used is 0, nobody will ever touch that entry again;
1042 * we'll eliminate all paths to it before dropping sysctl_lock
1043 */
1044 if (unlikely(p->used)) {
1045 struct completion wait;
1046 init_completion(&wait);
1047 p->unregistering = &wait;
1048 spin_unlock(&sysctl_lock);
1049 wait_for_completion(&wait);
1050 spin_lock(&sysctl_lock);
1051 }
1052 /*
1053 * do not remove from the list until nobody holds it; walking the
1054 * list in do_sysctl() relies on that.
1055 */
1056 list_del_init(&p->ctl_entry);
1057}
1058
1da177e4
LT
1059void __init sysctl_init(void)
1060{
b89a8171 1061#ifdef CONFIG_PROC_SYSCTL
330d57fb 1062 register_proc_table(root_table, proc_sys_root, &root_table_header);
1da177e4
LT
1063#endif
1064}
1065
b89a8171 1066#ifdef CONFIG_SYSCTL_SYSCALL
1da177e4
LT
1067int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1068 void __user *newval, size_t newlen)
1069{
1070 struct list_head *tmp;
330d57fb 1071 int error = -ENOTDIR;
1da177e4
LT
1072
1073 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1074 return -ENOTDIR;
1075 if (oldval) {
1076 int old_len;
1077 if (!oldlenp || get_user(old_len, oldlenp))
1078 return -EFAULT;
1079 }
330d57fb 1080 spin_lock(&sysctl_lock);
1da177e4
LT
1081 tmp = &root_table_header.ctl_entry;
1082 do {
1083 struct ctl_table_header *head =
1084 list_entry(tmp, struct ctl_table_header, ctl_entry);
330d57fb
AV
1085
1086 if (!use_table(head))
1087 continue;
1088
1089 spin_unlock(&sysctl_lock);
1090
1091 error = parse_table(name, nlen, oldval, oldlenp,
1f29bcd7 1092 newval, newlen, head->ctl_table);
330d57fb
AV
1093
1094 spin_lock(&sysctl_lock);
1095 unuse_table(head);
1da177e4 1096 if (error != -ENOTDIR)
330d57fb
AV
1097 break;
1098 } while ((tmp = tmp->next) != &root_table_header.ctl_entry);
1099 spin_unlock(&sysctl_lock);
1100 return error;
1da177e4
LT
1101}
1102
1103asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1104{
1105 struct __sysctl_args tmp;
1106 int error;
1107
1108 if (copy_from_user(&tmp, args, sizeof(tmp)))
1109 return -EFAULT;
1110
1111 lock_kernel();
1112 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1113 tmp.newval, tmp.newlen);
1114 unlock_kernel();
1115 return error;
1116}
b89a8171 1117#endif /* CONFIG_SYSCTL_SYSCALL */
1da177e4
LT
1118
1119/*
1120 * ctl_perm does NOT grant the superuser all rights automatically, because
1121 * some sysctl variables are readonly even to root.
1122 */
1123
1124static int test_perm(int mode, int op)
1125{
1126 if (!current->euid)
1127 mode >>= 6;
1128 else if (in_egroup_p(0))
1129 mode >>= 3;
1130 if ((mode & op & 0007) == op)
1131 return 0;
1132 return -EACCES;
1133}
1134
1135static inline int ctl_perm(ctl_table *table, int op)
1136{
1137 int error;
1138 error = security_sysctl(table, op);
1139 if (error)
1140 return error;
1141 return test_perm(table->mode, op);
1142}
1143
b89a8171 1144#ifdef CONFIG_SYSCTL_SYSCALL
1da177e4
LT
1145static int parse_table(int __user *name, int nlen,
1146 void __user *oldval, size_t __user *oldlenp,
1147 void __user *newval, size_t newlen,
1f29bcd7 1148 ctl_table *table)
1da177e4
LT
1149{
1150 int n;
1151repeat:
1152 if (!nlen)
1153 return -ENOTDIR;
1154 if (get_user(n, name))
1155 return -EFAULT;
d99f160a
EB
1156 for ( ; table->ctl_name || table->procname; table++) {
1157 if (!table->ctl_name)
1158 continue;
1da177e4
LT
1159 if (n == table->ctl_name || table->ctl_name == CTL_ANY) {
1160 int error;
1161 if (table->child) {
1162 if (ctl_perm(table, 001))
1163 return -EPERM;
1164 if (table->strategy) {
1165 error = table->strategy(
1166 table, name, nlen,
1167 oldval, oldlenp,
1f29bcd7 1168 newval, newlen);
1da177e4
LT
1169 if (error)
1170 return error;
1171 }
1172 name++;
1173 nlen--;
1174 table = table->child;
1175 goto repeat;
1176 }
1177 error = do_sysctl_strategy(table, name, nlen,
1178 oldval, oldlenp,
1f29bcd7 1179 newval, newlen);
1da177e4
LT
1180 return error;
1181 }
1182 }
1183 return -ENOTDIR;
1184}
1185
1186/* Perform the actual read/write of a sysctl table entry. */
1187int do_sysctl_strategy (ctl_table *table,
1188 int __user *name, int nlen,
1189 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 1190 void __user *newval, size_t newlen)
1da177e4
LT
1191{
1192 int op = 0, rc;
1193 size_t len;
1194
1195 if (oldval)
1196 op |= 004;
1197 if (newval)
1198 op |= 002;
1199 if (ctl_perm(table, op))
1200 return -EPERM;
1201
1202 if (table->strategy) {
1203 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1f29bcd7 1204 newval, newlen);
1da177e4
LT
1205 if (rc < 0)
1206 return rc;
1207 if (rc > 0)
1208 return 0;
1209 }
1210
1211 /* If there is no strategy routine, or if the strategy returns
1212 * zero, proceed with automatic r/w */
1213 if (table->data && table->maxlen) {
1214 if (oldval && oldlenp) {
1215 if (get_user(len, oldlenp))
1216 return -EFAULT;
1217 if (len) {
1218 if (len > table->maxlen)
1219 len = table->maxlen;
1220 if(copy_to_user(oldval, table->data, len))
1221 return -EFAULT;
1222 if(put_user(len, oldlenp))
1223 return -EFAULT;
1224 }
1225 }
1226 if (newval && newlen) {
1227 len = newlen;
1228 if (len > table->maxlen)
1229 len = table->maxlen;
1230 if(copy_from_user(table->data, newval, len))
1231 return -EFAULT;
1232 }
1233 }
1234 return 0;
1235}
b89a8171 1236#endif /* CONFIG_SYSCTL_SYSCALL */
1da177e4
LT
1237
1238/**
1239 * register_sysctl_table - register a sysctl hierarchy
1240 * @table: the top-level table structure
1241 * @insert_at_head: whether the entry should be inserted in front or at the end
1242 *
1243 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1244 * array. An entry with a ctl_name of 0 terminates the table.
1245 *
1246 * The members of the &ctl_table structure are used as follows:
1247 *
1248 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1249 * must be unique within that level of sysctl
1250 *
1251 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1252 * enter a sysctl file
1253 *
1254 * data - a pointer to data for use by proc_handler
1255 *
1256 * maxlen - the maximum size in bytes of the data
1257 *
1258 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1259 *
1260 * child - a pointer to the child sysctl table if this entry is a directory, or
1261 * %NULL.
1262 *
1263 * proc_handler - the text handler routine (described below)
1264 *
1265 * strategy - the strategy routine (described below)
1266 *
1267 * de - for internal use by the sysctl routines
1268 *
1269 * extra1, extra2 - extra pointers usable by the proc handler routines
1270 *
1271 * Leaf nodes in the sysctl tree will be represented by a single file
1272 * under /proc; non-leaf nodes will be represented by directories.
1273 *
1274 * sysctl(2) can automatically manage read and write requests through
1275 * the sysctl table. The data and maxlen fields of the ctl_table
1276 * struct enable minimal validation of the values being written to be
1277 * performed, and the mode field allows minimal authentication.
1278 *
1279 * More sophisticated management can be enabled by the provision of a
1280 * strategy routine with the table entry. This will be called before
1281 * any automatic read or write of the data is performed.
1282 *
1283 * The strategy routine may return
1284 *
1285 * < 0 - Error occurred (error is passed to user process)
1286 *
1287 * 0 - OK - proceed with automatic read or write.
1288 *
1289 * > 0 - OK - read or write has been done by the strategy routine, so
1290 * return immediately.
1291 *
1292 * There must be a proc_handler routine for any terminal nodes
1293 * mirrored under /proc/sys (non-terminals are handled by a built-in
1294 * directory handler). Several default handlers are available to
1295 * cover common cases -
1296 *
1297 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1298 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1299 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1300 *
1301 * It is the handler's job to read the input buffer from user memory
1302 * and process it. The handler should return 0 on success.
1303 *
1304 * This routine returns %NULL on a failure to register, and a pointer
1305 * to the table header on success.
1306 */
1307struct ctl_table_header *register_sysctl_table(ctl_table * table,
1308 int insert_at_head)
1309{
1310 struct ctl_table_header *tmp;
1311 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1312 if (!tmp)
1313 return NULL;
1314 tmp->ctl_table = table;
1315 INIT_LIST_HEAD(&tmp->ctl_entry);
330d57fb
AV
1316 tmp->used = 0;
1317 tmp->unregistering = NULL;
1318 spin_lock(&sysctl_lock);
1da177e4
LT
1319 if (insert_at_head)
1320 list_add(&tmp->ctl_entry, &root_table_header.ctl_entry);
1321 else
1322 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
330d57fb 1323 spin_unlock(&sysctl_lock);
b89a8171 1324#ifdef CONFIG_PROC_SYSCTL
330d57fb 1325 register_proc_table(table, proc_sys_root, tmp);
1da177e4
LT
1326#endif
1327 return tmp;
1328}
1329
1330/**
1331 * unregister_sysctl_table - unregister a sysctl table hierarchy
1332 * @header: the header returned from register_sysctl_table
1333 *
1334 * Unregisters the sysctl table and all children. proc entries may not
1335 * actually be removed until they are no longer used by anyone.
1336 */
1337void unregister_sysctl_table(struct ctl_table_header * header)
1338{
330d57fb
AV
1339 might_sleep();
1340 spin_lock(&sysctl_lock);
1341 start_unregistering(header);
b89a8171 1342#ifdef CONFIG_PROC_SYSCTL
1da177e4
LT
1343 unregister_proc_table(header->ctl_table, proc_sys_root);
1344#endif
330d57fb 1345 spin_unlock(&sysctl_lock);
1da177e4
LT
1346 kfree(header);
1347}
1348
b89a8171
EB
1349#else /* !CONFIG_SYSCTL */
1350struct ctl_table_header * register_sysctl_table(ctl_table * table,
1351 int insert_at_head)
1352{
1353 return NULL;
1354}
1355
1356void unregister_sysctl_table(struct ctl_table_header * table)
1357{
1358}
1359
1360#endif /* CONFIG_SYSCTL */
1361
1da177e4
LT
1362/*
1363 * /proc/sys support
1364 */
1365
b89a8171 1366#ifdef CONFIG_PROC_SYSCTL
1da177e4
LT
1367
1368/* Scan the sysctl entries in table and add them all into /proc */
330d57fb 1369static void register_proc_table(ctl_table * table, struct proc_dir_entry *root, void *set)
1da177e4
LT
1370{
1371 struct proc_dir_entry *de;
1372 int len;
1373 mode_t mode;
1374
d99f160a 1375 for (; table->ctl_name || table->procname; table++) {
1da177e4
LT
1376 /* Can't do anything without a proc name. */
1377 if (!table->procname)
1378 continue;
1379 /* Maybe we can't do anything with it... */
1380 if (!table->proc_handler && !table->child) {
1381 printk(KERN_WARNING "SYSCTL: Can't register %s\n",
1382 table->procname);
1383 continue;
1384 }
1385
1386 len = strlen(table->procname);
1387 mode = table->mode;
1388
1389 de = NULL;
1390 if (table->proc_handler)
1391 mode |= S_IFREG;
1392 else {
1393 mode |= S_IFDIR;
1394 for (de = root->subdir; de; de = de->next) {
1395 if (proc_match(len, table->procname, de))
1396 break;
1397 }
1398 /* If the subdir exists already, de is non-NULL */
1399 }
1400
1401 if (!de) {
1402 de = create_proc_entry(table->procname, mode, root);
1403 if (!de)
1404 continue;
330d57fb 1405 de->set = set;
1da177e4
LT
1406 de->data = (void *) table;
1407 if (table->proc_handler)
1408 de->proc_fops = &proc_sys_file_operations;
1409 }
1410 table->de = de;
1411 if (de->mode & S_IFDIR)
330d57fb 1412 register_proc_table(table->child, de, set);
1da177e4
LT
1413 }
1414}
1415
1416/*
1417 * Unregister a /proc sysctl table and any subdirectories.
1418 */
1419static void unregister_proc_table(ctl_table * table, struct proc_dir_entry *root)
1420{
1421 struct proc_dir_entry *de;
d99f160a 1422 for (; table->ctl_name || table->procname; table++) {
1da177e4
LT
1423 if (!(de = table->de))
1424 continue;
1425 if (de->mode & S_IFDIR) {
1426 if (!table->child) {
1427 printk (KERN_ALERT "Help - malformed sysctl tree on free\n");
1428 continue;
1429 }
1430 unregister_proc_table(table->child, de);
1431
1432 /* Don't unregister directories which still have entries.. */
1433 if (de->subdir)
1434 continue;
1435 }
1436
330d57fb
AV
1437 /*
1438 * In any case, mark the entry as goner; we'll keep it
1439 * around if it's busy, but we'll know to do nothing with
1440 * its fields. We are under sysctl_lock here.
1441 */
1442 de->data = NULL;
1443
1da177e4
LT
1444 /* Don't unregister proc entries that are still being used.. */
1445 if (atomic_read(&de->count))
1446 continue;
1447
1448 table->de = NULL;
1449 remove_proc_entry(table->procname, root);
1450 }
1451}
1452
1453static ssize_t do_rw_proc(int write, struct file * file, char __user * buf,
1454 size_t count, loff_t *ppos)
1455{
1456 int op;
f3a43f3f 1457 struct proc_dir_entry *de = PDE(file->f_path.dentry->d_inode);
1da177e4
LT
1458 struct ctl_table *table;
1459 size_t res;
330d57fb 1460 ssize_t error = -ENOTDIR;
1da177e4 1461
330d57fb
AV
1462 spin_lock(&sysctl_lock);
1463 if (de && de->data && use_table(de->set)) {
1464 /*
1465 * at that point we know that sysctl was not unregistered
1466 * and won't be until we finish
1467 */
1468 spin_unlock(&sysctl_lock);
1469 table = (struct ctl_table *) de->data;
1470 if (!table || !table->proc_handler)
1471 goto out;
1472 error = -EPERM;
1473 op = (write ? 002 : 004);
1474 if (ctl_perm(table, op))
1475 goto out;
1476
1477 /* careful: calling conventions are nasty here */
1478 res = count;
1479 error = (*table->proc_handler)(table, write, file,
1480 buf, &res, ppos);
1481 if (!error)
1482 error = res;
1483 out:
1484 spin_lock(&sysctl_lock);
1485 unuse_table(de->set);
1486 }
1487 spin_unlock(&sysctl_lock);
1488 return error;
1da177e4
LT
1489}
1490
1491static int proc_opensys(struct inode *inode, struct file *file)
1492{
1493 if (file->f_mode & FMODE_WRITE) {
1494 /*
1495 * sysctl entries that are not writable,
1496 * are _NOT_ writable, capabilities or not.
1497 */
1498 if (!(inode->i_mode & S_IWUSR))
1499 return -EPERM;
1500 }
1501
1502 return 0;
1503}
1504
1505static ssize_t proc_readsys(struct file * file, char __user * buf,
1506 size_t count, loff_t *ppos)
1507{
1508 return do_rw_proc(0, file, buf, count, ppos);
1509}
1510
1511static ssize_t proc_writesys(struct file * file, const char __user * buf,
1512 size_t count, loff_t *ppos)
1513{
1514 return do_rw_proc(1, file, (char __user *) buf, count, ppos);
1515}
1516
b1ba4ddd
AB
1517static int _proc_do_string(void* data, int maxlen, int write,
1518 struct file *filp, void __user *buffer,
1519 size_t *lenp, loff_t *ppos)
1da177e4
LT
1520{
1521 size_t len;
1522 char __user *p;
1523 char c;
8d060877
ON
1524
1525 if (!data || !maxlen || !*lenp) {
1da177e4
LT
1526 *lenp = 0;
1527 return 0;
1528 }
8d060877 1529
1da177e4
LT
1530 if (write) {
1531 len = 0;
1532 p = buffer;
1533 while (len < *lenp) {
1534 if (get_user(c, p++))
1535 return -EFAULT;
1536 if (c == 0 || c == '\n')
1537 break;
1538 len++;
1539 }
f5dd3d6f
SV
1540 if (len >= maxlen)
1541 len = maxlen-1;
1542 if(copy_from_user(data, buffer, len))
1da177e4 1543 return -EFAULT;
f5dd3d6f 1544 ((char *) data)[len] = 0;
1da177e4
LT
1545 *ppos += *lenp;
1546 } else {
f5dd3d6f
SV
1547 len = strlen(data);
1548 if (len > maxlen)
1549 len = maxlen;
8d060877
ON
1550
1551 if (*ppos > len) {
1552 *lenp = 0;
1553 return 0;
1554 }
1555
1556 data += *ppos;
1557 len -= *ppos;
1558
1da177e4
LT
1559 if (len > *lenp)
1560 len = *lenp;
1561 if (len)
f5dd3d6f 1562 if(copy_to_user(buffer, data, len))
1da177e4
LT
1563 return -EFAULT;
1564 if (len < *lenp) {
1565 if(put_user('\n', ((char __user *) buffer) + len))
1566 return -EFAULT;
1567 len++;
1568 }
1569 *lenp = len;
1570 *ppos += len;
1571 }
1572 return 0;
1573}
1574
f5dd3d6f
SV
1575/**
1576 * proc_dostring - read a string sysctl
1577 * @table: the sysctl table
1578 * @write: %TRUE if this is a write to the sysctl file
1579 * @filp: the file structure
1580 * @buffer: the user buffer
1581 * @lenp: the size of the user buffer
1582 * @ppos: file position
1583 *
1584 * Reads/writes a string from/to the user buffer. If the kernel
1585 * buffer provided is not large enough to hold the string, the
1586 * string is truncated. The copied string is %NULL-terminated.
1587 * If the string is being read by the user process, it is copied
1588 * and a newline '\n' is added. It is truncated if the buffer is
1589 * not large enough.
1590 *
1591 * Returns 0 on success.
1592 */
1593int proc_dostring(ctl_table *table, int write, struct file *filp,
1594 void __user *buffer, size_t *lenp, loff_t *ppos)
1595{
1596 return _proc_do_string(table->data, table->maxlen, write, filp,
1597 buffer, lenp, ppos);
1598}
1599
1da177e4
LT
1600
1601static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1602 int *valp,
1603 int write, void *data)
1604{
1605 if (write) {
1606 *valp = *negp ? -*lvalp : *lvalp;
1607 } else {
1608 int val = *valp;
1609 if (val < 0) {
1610 *negp = -1;
1611 *lvalp = (unsigned long)-val;
1612 } else {
1613 *negp = 0;
1614 *lvalp = (unsigned long)val;
1615 }
1616 }
1617 return 0;
1618}
1619
fcfbd547
KK
1620static int __do_proc_dointvec(void *tbl_data, ctl_table *table,
1621 int write, struct file *filp, void __user *buffer,
1622 size_t *lenp, loff_t *ppos,
1da177e4
LT
1623 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1624 int write, void *data),
1625 void *data)
1626{
1627#define TMPBUFLEN 21
1628 int *i, vleft, first=1, neg, val;
1629 unsigned long lval;
1630 size_t left, len;
1631
1632 char buf[TMPBUFLEN], *p;
1633 char __user *s = buffer;
1634
fcfbd547 1635 if (!tbl_data || !table->maxlen || !*lenp ||
1da177e4
LT
1636 (*ppos && !write)) {
1637 *lenp = 0;
1638 return 0;
1639 }
1640
fcfbd547 1641 i = (int *) tbl_data;
1da177e4
LT
1642 vleft = table->maxlen / sizeof(*i);
1643 left = *lenp;
1644
1645 if (!conv)
1646 conv = do_proc_dointvec_conv;
1647
1648 for (; left && vleft--; i++, first=0) {
1649 if (write) {
1650 while (left) {
1651 char c;
1652 if (get_user(c, s))
1653 return -EFAULT;
1654 if (!isspace(c))
1655 break;
1656 left--;
1657 s++;
1658 }
1659 if (!left)
1660 break;
1661 neg = 0;
1662 len = left;
1663 if (len > sizeof(buf) - 1)
1664 len = sizeof(buf) - 1;
1665 if (copy_from_user(buf, s, len))
1666 return -EFAULT;
1667 buf[len] = 0;
1668 p = buf;
1669 if (*p == '-' && left > 1) {
1670 neg = 1;
bd9b0bac 1671 p++;
1da177e4
LT
1672 }
1673 if (*p < '0' || *p > '9')
1674 break;
1675
1676 lval = simple_strtoul(p, &p, 0);
1677
1678 len = p-buf;
1679 if ((len < left) && *p && !isspace(*p))
1680 break;
1681 if (neg)
1682 val = -val;
1683 s += len;
1684 left -= len;
1685
1686 if (conv(&neg, &lval, i, 1, data))
1687 break;
1688 } else {
1689 p = buf;
1690 if (!first)
1691 *p++ = '\t';
1692
1693 if (conv(&neg, &lval, i, 0, data))
1694 break;
1695
1696 sprintf(p, "%s%lu", neg ? "-" : "", lval);
1697 len = strlen(buf);
1698 if (len > left)
1699 len = left;
1700 if(copy_to_user(s, buf, len))
1701 return -EFAULT;
1702 left -= len;
1703 s += len;
1704 }
1705 }
1706
1707 if (!write && !first && left) {
1708 if(put_user('\n', s))
1709 return -EFAULT;
1710 left--, s++;
1711 }
1712 if (write) {
1713 while (left) {
1714 char c;
1715 if (get_user(c, s++))
1716 return -EFAULT;
1717 if (!isspace(c))
1718 break;
1719 left--;
1720 }
1721 }
1722 if (write && first)
1723 return -EINVAL;
1724 *lenp -= left;
1725 *ppos += *lenp;
1726 return 0;
1727#undef TMPBUFLEN
1728}
1729
fcfbd547
KK
1730static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1731 void __user *buffer, size_t *lenp, loff_t *ppos,
1732 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1733 int write, void *data),
1734 void *data)
1735{
1736 return __do_proc_dointvec(table->data, table, write, filp,
1737 buffer, lenp, ppos, conv, data);
1738}
1739
1da177e4
LT
1740/**
1741 * proc_dointvec - read a vector of integers
1742 * @table: the sysctl table
1743 * @write: %TRUE if this is a write to the sysctl file
1744 * @filp: the file structure
1745 * @buffer: the user buffer
1746 * @lenp: the size of the user buffer
1747 * @ppos: file position
1748 *
1749 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1750 * values from/to the user buffer, treated as an ASCII string.
1751 *
1752 * Returns 0 on success.
1753 */
1754int proc_dointvec(ctl_table *table, int write, struct file *filp,
1755 void __user *buffer, size_t *lenp, loff_t *ppos)
1756{
1757 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1758 NULL,NULL);
1759}
1760
1761#define OP_SET 0
1762#define OP_AND 1
34f5a398 1763#define OP_OR 2
1da177e4
LT
1764
1765static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1766 int *valp,
1767 int write, void *data)
1768{
1769 int op = *(int *)data;
1770 if (write) {
1771 int val = *negp ? -*lvalp : *lvalp;
1772 switch(op) {
1773 case OP_SET: *valp = val; break;
1774 case OP_AND: *valp &= val; break;
34f5a398 1775 case OP_OR: *valp |= val; break;
1da177e4
LT
1776 }
1777 } else {
1778 int val = *valp;
1779 if (val < 0) {
1780 *negp = -1;
1781 *lvalp = (unsigned long)-val;
1782 } else {
1783 *negp = 0;
1784 *lvalp = (unsigned long)val;
1785 }
1786 }
1787 return 0;
1788}
1789
1790/*
1791 * init may raise the set.
1792 */
1793
1794int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1795 void __user *buffer, size_t *lenp, loff_t *ppos)
1796{
1797 int op;
1798
6ff1b442 1799 if (write && !capable(CAP_SYS_MODULE)) {
1da177e4
LT
1800 return -EPERM;
1801 }
1802
f400e198 1803 op = is_init(current) ? OP_SET : OP_AND;
1da177e4
LT
1804 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1805 do_proc_dointvec_bset_conv,&op);
1806}
1807
34f5a398
TT
1808/*
1809 * Taint values can only be increased
1810 */
1811static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
1812 void __user *buffer, size_t *lenp, loff_t *ppos)
1813{
1814 int op;
1815
1816 if (!capable(CAP_SYS_ADMIN))
1817 return -EPERM;
1818
1819 op = OP_OR;
1820 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1821 do_proc_dointvec_bset_conv,&op);
1822}
1823
1da177e4
LT
1824struct do_proc_dointvec_minmax_conv_param {
1825 int *min;
1826 int *max;
1827};
1828
1829static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1830 int *valp,
1831 int write, void *data)
1832{
1833 struct do_proc_dointvec_minmax_conv_param *param = data;
1834 if (write) {
1835 int val = *negp ? -*lvalp : *lvalp;
1836 if ((param->min && *param->min > val) ||
1837 (param->max && *param->max < val))
1838 return -EINVAL;
1839 *valp = val;
1840 } else {
1841 int val = *valp;
1842 if (val < 0) {
1843 *negp = -1;
1844 *lvalp = (unsigned long)-val;
1845 } else {
1846 *negp = 0;
1847 *lvalp = (unsigned long)val;
1848 }
1849 }
1850 return 0;
1851}
1852
1853/**
1854 * proc_dointvec_minmax - read a vector of integers with min/max values
1855 * @table: the sysctl table
1856 * @write: %TRUE if this is a write to the sysctl file
1857 * @filp: the file structure
1858 * @buffer: the user buffer
1859 * @lenp: the size of the user buffer
1860 * @ppos: file position
1861 *
1862 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1863 * values from/to the user buffer, treated as an ASCII string.
1864 *
1865 * This routine will ensure the values are within the range specified by
1866 * table->extra1 (min) and table->extra2 (max).
1867 *
1868 * Returns 0 on success.
1869 */
1870int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1871 void __user *buffer, size_t *lenp, loff_t *ppos)
1872{
1873 struct do_proc_dointvec_minmax_conv_param param = {
1874 .min = (int *) table->extra1,
1875 .max = (int *) table->extra2,
1876 };
1877 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1878 do_proc_dointvec_minmax_conv, &param);
1879}
1880
fcfbd547 1881static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
1da177e4
LT
1882 struct file *filp,
1883 void __user *buffer,
1884 size_t *lenp, loff_t *ppos,
1885 unsigned long convmul,
1886 unsigned long convdiv)
1887{
1888#define TMPBUFLEN 21
1889 unsigned long *i, *min, *max, val;
1890 int vleft, first=1, neg;
1891 size_t len, left;
1892 char buf[TMPBUFLEN], *p;
1893 char __user *s = buffer;
1894
fcfbd547 1895 if (!data || !table->maxlen || !*lenp ||
1da177e4
LT
1896 (*ppos && !write)) {
1897 *lenp = 0;
1898 return 0;
1899 }
1900
fcfbd547 1901 i = (unsigned long *) data;
1da177e4
LT
1902 min = (unsigned long *) table->extra1;
1903 max = (unsigned long *) table->extra2;
1904 vleft = table->maxlen / sizeof(unsigned long);
1905 left = *lenp;
1906
1907 for (; left && vleft--; i++, min++, max++, first=0) {
1908 if (write) {
1909 while (left) {
1910 char c;
1911 if (get_user(c, s))
1912 return -EFAULT;
1913 if (!isspace(c))
1914 break;
1915 left--;
1916 s++;
1917 }
1918 if (!left)
1919 break;
1920 neg = 0;
1921 len = left;
1922 if (len > TMPBUFLEN-1)
1923 len = TMPBUFLEN-1;
1924 if (copy_from_user(buf, s, len))
1925 return -EFAULT;
1926 buf[len] = 0;
1927 p = buf;
1928 if (*p == '-' && left > 1) {
1929 neg = 1;
bd9b0bac 1930 p++;
1da177e4
LT
1931 }
1932 if (*p < '0' || *p > '9')
1933 break;
1934 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1935 len = p-buf;
1936 if ((len < left) && *p && !isspace(*p))
1937 break;
1938 if (neg)
1939 val = -val;
1940 s += len;
1941 left -= len;
1942
1943 if(neg)
1944 continue;
1945 if ((min && val < *min) || (max && val > *max))
1946 continue;
1947 *i = val;
1948 } else {
1949 p = buf;
1950 if (!first)
1951 *p++ = '\t';
1952 sprintf(p, "%lu", convdiv * (*i) / convmul);
1953 len = strlen(buf);
1954 if (len > left)
1955 len = left;
1956 if(copy_to_user(s, buf, len))
1957 return -EFAULT;
1958 left -= len;
1959 s += len;
1960 }
1961 }
1962
1963 if (!write && !first && left) {
1964 if(put_user('\n', s))
1965 return -EFAULT;
1966 left--, s++;
1967 }
1968 if (write) {
1969 while (left) {
1970 char c;
1971 if (get_user(c, s++))
1972 return -EFAULT;
1973 if (!isspace(c))
1974 break;
1975 left--;
1976 }
1977 }
1978 if (write && first)
1979 return -EINVAL;
1980 *lenp -= left;
1981 *ppos += *lenp;
1982 return 0;
1983#undef TMPBUFLEN
1984}
1985
fcfbd547
KK
1986static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1987 struct file *filp,
1988 void __user *buffer,
1989 size_t *lenp, loff_t *ppos,
1990 unsigned long convmul,
1991 unsigned long convdiv)
1992{
1993 return __do_proc_doulongvec_minmax(table->data, table, write,
1994 filp, buffer, lenp, ppos, convmul, convdiv);
1995}
1996
1da177e4
LT
1997/**
1998 * proc_doulongvec_minmax - read a vector of long integers with min/max values
1999 * @table: the sysctl table
2000 * @write: %TRUE if this is a write to the sysctl file
2001 * @filp: the file structure
2002 * @buffer: the user buffer
2003 * @lenp: the size of the user buffer
2004 * @ppos: file position
2005 *
2006 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2007 * values from/to the user buffer, treated as an ASCII string.
2008 *
2009 * This routine will ensure the values are within the range specified by
2010 * table->extra1 (min) and table->extra2 (max).
2011 *
2012 * Returns 0 on success.
2013 */
2014int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2015 void __user *buffer, size_t *lenp, loff_t *ppos)
2016{
2017 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2018}
2019
2020/**
2021 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2022 * @table: the sysctl table
2023 * @write: %TRUE if this is a write to the sysctl file
2024 * @filp: the file structure
2025 * @buffer: the user buffer
2026 * @lenp: the size of the user buffer
2027 * @ppos: file position
2028 *
2029 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2030 * values from/to the user buffer, treated as an ASCII string. The values
2031 * are treated as milliseconds, and converted to jiffies when they are stored.
2032 *
2033 * This routine will ensure the values are within the range specified by
2034 * table->extra1 (min) and table->extra2 (max).
2035 *
2036 * Returns 0 on success.
2037 */
2038int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2039 struct file *filp,
2040 void __user *buffer,
2041 size_t *lenp, loff_t *ppos)
2042{
2043 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2044 lenp, ppos, HZ, 1000l);
2045}
2046
2047
2048static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2049 int *valp,
2050 int write, void *data)
2051{
2052 if (write) {
cba9f33d
BS
2053 if (*lvalp > LONG_MAX / HZ)
2054 return 1;
1da177e4
LT
2055 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2056 } else {
2057 int val = *valp;
2058 unsigned long lval;
2059 if (val < 0) {
2060 *negp = -1;
2061 lval = (unsigned long)-val;
2062 } else {
2063 *negp = 0;
2064 lval = (unsigned long)val;
2065 }
2066 *lvalp = lval / HZ;
2067 }
2068 return 0;
2069}
2070
2071static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2072 int *valp,
2073 int write, void *data)
2074{
2075 if (write) {
cba9f33d
BS
2076 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2077 return 1;
1da177e4
LT
2078 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2079 } else {
2080 int val = *valp;
2081 unsigned long lval;
2082 if (val < 0) {
2083 *negp = -1;
2084 lval = (unsigned long)-val;
2085 } else {
2086 *negp = 0;
2087 lval = (unsigned long)val;
2088 }
2089 *lvalp = jiffies_to_clock_t(lval);
2090 }
2091 return 0;
2092}
2093
2094static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2095 int *valp,
2096 int write, void *data)
2097{
2098 if (write) {
2099 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2100 } else {
2101 int val = *valp;
2102 unsigned long lval;
2103 if (val < 0) {
2104 *negp = -1;
2105 lval = (unsigned long)-val;
2106 } else {
2107 *negp = 0;
2108 lval = (unsigned long)val;
2109 }
2110 *lvalp = jiffies_to_msecs(lval);
2111 }
2112 return 0;
2113}
2114
2115/**
2116 * proc_dointvec_jiffies - read a vector of integers as seconds
2117 * @table: the sysctl table
2118 * @write: %TRUE if this is a write to the sysctl file
2119 * @filp: the file structure
2120 * @buffer: the user buffer
2121 * @lenp: the size of the user buffer
2122 * @ppos: file position
2123 *
2124 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2125 * values from/to the user buffer, treated as an ASCII string.
2126 * The values read are assumed to be in seconds, and are converted into
2127 * jiffies.
2128 *
2129 * Returns 0 on success.
2130 */
2131int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2132 void __user *buffer, size_t *lenp, loff_t *ppos)
2133{
2134 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2135 do_proc_dointvec_jiffies_conv,NULL);
2136}
2137
2138/**
2139 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2140 * @table: the sysctl table
2141 * @write: %TRUE if this is a write to the sysctl file
2142 * @filp: the file structure
2143 * @buffer: the user buffer
2144 * @lenp: the size of the user buffer
1e5d5331 2145 * @ppos: pointer to the file position
1da177e4
LT
2146 *
2147 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2148 * values from/to the user buffer, treated as an ASCII string.
2149 * The values read are assumed to be in 1/USER_HZ seconds, and
2150 * are converted into jiffies.
2151 *
2152 * Returns 0 on success.
2153 */
2154int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2155 void __user *buffer, size_t *lenp, loff_t *ppos)
2156{
2157 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2158 do_proc_dointvec_userhz_jiffies_conv,NULL);
2159}
2160
2161/**
2162 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2163 * @table: the sysctl table
2164 * @write: %TRUE if this is a write to the sysctl file
2165 * @filp: the file structure
2166 * @buffer: the user buffer
2167 * @lenp: the size of the user buffer
67be2dd1
MW
2168 * @ppos: file position
2169 * @ppos: the current position in the file
1da177e4
LT
2170 *
2171 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2172 * values from/to the user buffer, treated as an ASCII string.
2173 * The values read are assumed to be in 1/1000 seconds, and
2174 * are converted into jiffies.
2175 *
2176 * Returns 0 on success.
2177 */
2178int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2179 void __user *buffer, size_t *lenp, loff_t *ppos)
2180{
2181 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2182 do_proc_dointvec_ms_jiffies_conv, NULL);
2183}
2184
9ec52099
CLG
2185static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
2186 void __user *buffer, size_t *lenp, loff_t *ppos)
2187{
2188 struct pid *new_pid;
2189 pid_t tmp;
2190 int r;
2191
2192 tmp = pid_nr(cad_pid);
2193
2194 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2195 lenp, ppos, NULL, NULL);
2196 if (r || !write)
2197 return r;
2198
2199 new_pid = find_get_pid(tmp);
2200 if (!new_pid)
2201 return -ESRCH;
2202
2203 put_pid(xchg(&cad_pid, new_pid));
2204 return 0;
2205}
2206
1da177e4
LT
2207#else /* CONFIG_PROC_FS */
2208
2209int proc_dostring(ctl_table *table, int write, struct file *filp,
2210 void __user *buffer, size_t *lenp, loff_t *ppos)
2211{
2212 return -ENOSYS;
2213}
2214
1da177e4
LT
2215int proc_dointvec(ctl_table *table, int write, struct file *filp,
2216 void __user *buffer, size_t *lenp, loff_t *ppos)
2217{
2218 return -ENOSYS;
2219}
2220
2221int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2222 void __user *buffer, size_t *lenp, loff_t *ppos)
2223{
2224 return -ENOSYS;
2225}
2226
2227int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2228 void __user *buffer, size_t *lenp, loff_t *ppos)
2229{
2230 return -ENOSYS;
2231}
2232
2233int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2234 void __user *buffer, size_t *lenp, loff_t *ppos)
2235{
2236 return -ENOSYS;
2237}
2238
2239int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2240 void __user *buffer, size_t *lenp, loff_t *ppos)
2241{
2242 return -ENOSYS;
2243}
2244
2245int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2246 void __user *buffer, size_t *lenp, loff_t *ppos)
2247{
2248 return -ENOSYS;
2249}
2250
2251int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2252 void __user *buffer, size_t *lenp, loff_t *ppos)
2253{
2254 return -ENOSYS;
2255}
2256
2257int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2258 struct file *filp,
2259 void __user *buffer,
2260 size_t *lenp, loff_t *ppos)
2261{
2262 return -ENOSYS;
2263}
2264
2265
2266#endif /* CONFIG_PROC_FS */
2267
2268
b89a8171 2269#ifdef CONFIG_SYSCTL_SYSCALL
1da177e4
LT
2270/*
2271 * General sysctl support routines
2272 */
2273
2274/* The generic string strategy routine: */
2275int sysctl_string(ctl_table *table, int __user *name, int nlen,
2276 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2277 void __user *newval, size_t newlen)
1da177e4 2278{
1da177e4
LT
2279 if (!table->data || !table->maxlen)
2280 return -ENOTDIR;
2281
2282 if (oldval && oldlenp) {
de9e007d
LT
2283 size_t bufsize;
2284 if (get_user(bufsize, oldlenp))
1da177e4 2285 return -EFAULT;
de9e007d
LT
2286 if (bufsize) {
2287 size_t len = strlen(table->data), copied;
2288
2289 /* This shouldn't trigger for a well-formed sysctl */
2290 if (len > table->maxlen)
1da177e4 2291 len = table->maxlen;
de9e007d
LT
2292
2293 /* Copy up to a max of bufsize-1 bytes of the string */
2294 copied = (len >= bufsize) ? bufsize - 1 : len;
2295
2296 if (copy_to_user(oldval, table->data, copied) ||
2297 put_user(0, (char __user *)(oldval + copied)))
1da177e4 2298 return -EFAULT;
de9e007d 2299 if (put_user(len, oldlenp))
1da177e4
LT
2300 return -EFAULT;
2301 }
2302 }
2303 if (newval && newlen) {
de9e007d 2304 size_t len = newlen;
1da177e4
LT
2305 if (len > table->maxlen)
2306 len = table->maxlen;
2307 if(copy_from_user(table->data, newval, len))
2308 return -EFAULT;
2309 if (len == table->maxlen)
2310 len--;
2311 ((char *) table->data)[len] = 0;
2312 }
82c9df82 2313 return 1;
1da177e4
LT
2314}
2315
2316/*
2317 * This function makes sure that all of the integers in the vector
2318 * are between the minimum and maximum values given in the arrays
2319 * table->extra1 and table->extra2, respectively.
2320 */
2321int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2322 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2323 void __user *newval, size_t newlen)
1da177e4
LT
2324{
2325
2326 if (newval && newlen) {
2327 int __user *vec = (int __user *) newval;
2328 int *min = (int *) table->extra1;
2329 int *max = (int *) table->extra2;
2330 size_t length;
2331 int i;
2332
2333 if (newlen % sizeof(int) != 0)
2334 return -EINVAL;
2335
2336 if (!table->extra1 && !table->extra2)
2337 return 0;
2338
2339 if (newlen > table->maxlen)
2340 newlen = table->maxlen;
2341 length = newlen / sizeof(int);
2342
2343 for (i = 0; i < length; i++) {
2344 int value;
2345 if (get_user(value, vec + i))
2346 return -EFAULT;
2347 if (min && value < min[i])
2348 return -EINVAL;
2349 if (max && value > max[i])
2350 return -EINVAL;
2351 }
2352 }
2353 return 0;
2354}
2355
2356/* Strategy function to convert jiffies to seconds */
2357int sysctl_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 2360{
3ee75ac3 2361 if (oldval && oldlenp) {
1da177e4 2362 size_t olen;
3ee75ac3
AD
2363
2364 if (get_user(olen, oldlenp))
2365 return -EFAULT;
2366 if (olen) {
2367 int val;
2368
2369 if (olen < sizeof(int))
2370 return -EINVAL;
2371
2372 val = *(int *)(table->data) / HZ;
2373 if (put_user(val, (int __user *)oldval))
2374 return -EFAULT;
2375 if (put_user(sizeof(int), oldlenp))
1da177e4 2376 return -EFAULT;
1da177e4 2377 }
1da177e4
LT
2378 }
2379 if (newval && newlen) {
2380 int new;
2381 if (newlen != sizeof(int))
2382 return -EINVAL;
2383 if (get_user(new, (int __user *)newval))
2384 return -EFAULT;
2385 *(int *)(table->data) = new*HZ;
2386 }
2387 return 1;
2388}
2389
2390/* Strategy function to convert jiffies to seconds */
2391int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2392 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2393 void __user *newval, size_t newlen)
1da177e4 2394{
3ee75ac3 2395 if (oldval && oldlenp) {
1da177e4 2396 size_t olen;
3ee75ac3
AD
2397
2398 if (get_user(olen, oldlenp))
2399 return -EFAULT;
2400 if (olen) {
2401 int val;
2402
2403 if (olen < sizeof(int))
2404 return -EINVAL;
2405
2406 val = jiffies_to_msecs(*(int *)(table->data));
2407 if (put_user(val, (int __user *)oldval))
2408 return -EFAULT;
2409 if (put_user(sizeof(int), oldlenp))
1da177e4 2410 return -EFAULT;
1da177e4 2411 }
1da177e4
LT
2412 }
2413 if (newval && newlen) {
2414 int new;
2415 if (newlen != sizeof(int))
2416 return -EINVAL;
2417 if (get_user(new, (int __user *)newval))
2418 return -EFAULT;
2419 *(int *)(table->data) = msecs_to_jiffies(new);
2420 }
2421 return 1;
2422}
2423
c4b8b769 2424
c4b8b769 2425
b89a8171 2426#else /* CONFIG_SYSCTL_SYSCALL */
1da177e4
LT
2427
2428
2429asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2430{
b89a8171 2431 static int msg_count;
0e009be8
EB
2432 struct __sysctl_args tmp;
2433 int name[CTL_MAXNAME];
2434 int i;
2435
2436 /* Read in the sysctl name for better debug message logging */
2437 if (copy_from_user(&tmp, args, sizeof(tmp)))
2438 return -EFAULT;
2439 if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
2440 return -ENOTDIR;
2441 for (i = 0; i < tmp.nlen; i++)
2442 if (get_user(name[i], tmp.name + i))
2443 return -EFAULT;
2444
2445 /* Ignore accesses to kernel.version */
2446 if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2447 goto out;
b89a8171
EB
2448
2449 if (msg_count < 5) {
2450 msg_count++;
2451 printk(KERN_INFO
2452 "warning: process `%s' used the removed sysctl "
0e009be8
EB
2453 "system call with ", current->comm);
2454 for (i = 0; i < tmp.nlen; i++)
2455 printk("%d.", name[i]);
2456 printk("\n");
b89a8171 2457 }
0e009be8 2458out:
1da177e4
LT
2459 return -ENOSYS;
2460}
2461
2462int sysctl_string(ctl_table *table, int __user *name, int nlen,
2463 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2464 void __user *newval, size_t newlen)
1da177e4
LT
2465{
2466 return -ENOSYS;
2467}
2468
2469int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2470 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2471 void __user *newval, size_t newlen)
1da177e4
LT
2472{
2473 return -ENOSYS;
2474}
2475
2476int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2477 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2478 void __user *newval, size_t newlen)
1da177e4
LT
2479{
2480 return -ENOSYS;
2481}
2482
2483int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2484 void __user *oldval, size_t __user *oldlenp,
1f29bcd7 2485 void __user *newval, size_t newlen)
1da177e4
LT
2486{
2487 return -ENOSYS;
2488}
2489
b89a8171 2490#endif /* CONFIG_SYSCTL_SYSCALL */
1da177e4
LT
2491
2492/*
2493 * No sense putting this after each symbol definition, twice,
2494 * exception granted :-)
2495 */
2496EXPORT_SYMBOL(proc_dointvec);
2497EXPORT_SYMBOL(proc_dointvec_jiffies);
2498EXPORT_SYMBOL(proc_dointvec_minmax);
2499EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2500EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2501EXPORT_SYMBOL(proc_dostring);
2502EXPORT_SYMBOL(proc_doulongvec_minmax);
2503EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2504EXPORT_SYMBOL(register_sysctl_table);
2505EXPORT_SYMBOL(sysctl_intvec);
2506EXPORT_SYMBOL(sysctl_jiffies);
2507EXPORT_SYMBOL(sysctl_ms_jiffies);
2508EXPORT_SYMBOL(sysctl_string);
2509EXPORT_SYMBOL(unregister_sysctl_table);