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[NET]: Allow group ownership of TUN/TAP devices.
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / kernel / sysctl.c
blob51f5dac42a00c9f56943a44b7d1865f604d84bde
1 /*
2 * sysctl.c: General linux system control interface
3 *
4 * Begun 24 March 1995, Stephen Tweedie
5 * Added /proc support, Dec 1995
6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9 * Dynamic registration fixes, Stephen Tweedie.
10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
12 * Horn.
13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
16 * Wendling.
17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
19 */
20
21 #include <linux/module.h>
22 #include <linux/mm.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/capability.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/capability.h>
31 #include <linux/smp_lock.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/security.h>
41 #include <linux/initrd.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/nfs_fs.h>
47 #include <linux/acpi.h>
48
49 #include <asm/uaccess.h>
50 #include <asm/processor.h>
51
52 extern int proc_nr_files(ctl_table *table, int write, struct file *filp,
53 void __user *buffer, size_t *lenp, loff_t *ppos);
54
55 #ifdef CONFIG_X86
56 #include <asm/nmi.h>
57 #include <asm/stacktrace.h>
58 #endif
59
60 #if defined(CONFIG_SYSCTL)
61
62 /* External variables not in a header file. */
63 extern int C_A_D;
64 extern int sysctl_overcommit_memory;
65 extern int sysctl_overcommit_ratio;
66 extern int sysctl_panic_on_oom;
67 extern int max_threads;
68 extern int core_uses_pid;
69 extern int suid_dumpable;
70 extern char core_pattern[];
71 extern int pid_max;
72 extern int min_free_kbytes;
73 extern int printk_ratelimit_jiffies;
74 extern int printk_ratelimit_burst;
75 extern int pid_max_min, pid_max_max;
76 extern int sysctl_drop_caches;
77 extern int percpu_pagelist_fraction;
78 extern int compat_log;
79 extern int maps_protect;
80 extern int sysctl_stat_interval;
81
82 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
83 static int maxolduid = 65535;
84 static int minolduid;
85 static int min_percpu_pagelist_fract = 8;
86
87 static int ngroups_max = NGROUPS_MAX;
88
89 #ifdef CONFIG_KMOD
90 extern char modprobe_path[];
91 #endif
92 #ifdef CONFIG_CHR_DEV_SG
93 extern int sg_big_buff;
94 #endif
95
96 #ifdef __sparc__
97 extern char reboot_command [];
98 extern int stop_a_enabled;
99 extern int scons_pwroff;
100 #endif
101
102 #ifdef __hppa__
103 extern int pwrsw_enabled;
104 extern int unaligned_enabled;
105 #endif
106
107 #ifdef CONFIG_S390
108 #ifdef CONFIG_MATHEMU
109 extern int sysctl_ieee_emulation_warnings;
110 #endif
111 extern int sysctl_userprocess_debug;
112 extern int spin_retry;
113 #endif
114
115 extern int sysctl_hz_timer;
116
117 #ifdef CONFIG_BSD_PROCESS_ACCT
118 extern int acct_parm[];
119 #endif
120
121 #ifdef CONFIG_IA64
122 extern int no_unaligned_warning;
123 #endif
124
125 #ifdef CONFIG_RT_MUTEXES
126 extern int max_lock_depth;
127 #endif
128
129 #ifdef CONFIG_SYSCTL_SYSCALL
130 static int parse_table(int __user *, int, void __user *, size_t __user *,
131 void __user *, size_t, ctl_table *);
132 #endif
133
134
135 #ifdef CONFIG_PROC_SYSCTL
136 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
137 void __user *buffer, size_t *lenp, loff_t *ppos);
138 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
139 void __user *buffer, size_t *lenp, loff_t *ppos);
140 #endif
141
142 static ctl_table root_table[];
143 static struct ctl_table_header root_table_header =
144 { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
145
146 static ctl_table kern_table[];
147 static ctl_table vm_table[];
148 static ctl_table fs_table[];
149 static ctl_table debug_table[];
150 static ctl_table dev_table[];
151 extern ctl_table random_table[];
152 #ifdef CONFIG_UNIX98_PTYS
153 extern ctl_table pty_table[];
154 #endif
155 #ifdef CONFIG_INOTIFY_USER
156 extern ctl_table inotify_table[];
157 #endif
158
159 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
160 int sysctl_legacy_va_layout;
161 #endif
162
163
164 /* The default sysctl tables: */
165
166 static ctl_table root_table[] = {
167 {
168 .ctl_name = CTL_KERN,
169 .procname = "kernel",
170 .mode = 0555,
171 .child = kern_table,
172 },
173 {
174 .ctl_name = CTL_VM,
175 .procname = "vm",
176 .mode = 0555,
177 .child = vm_table,
178 },
179 #ifdef CONFIG_NET
180 {
181 .ctl_name = CTL_NET,
182 .procname = "net",
183 .mode = 0555,
184 .child = net_table,
185 },
186 #endif
187 {
188 .ctl_name = CTL_FS,
189 .procname = "fs",
190 .mode = 0555,
191 .child = fs_table,
192 },
193 {
194 .ctl_name = CTL_DEBUG,
195 .procname = "debug",
196 .mode = 0555,
197 .child = debug_table,
198 },
199 {
200 .ctl_name = CTL_DEV,
201 .procname = "dev",
202 .mode = 0555,
203 .child = dev_table,
204 },
205
206 { .ctl_name = 0 }
207 };
208
209 #ifdef CONFIG_SCHED_DEBUG
210 static unsigned long min_sched_granularity_ns = 100000; /* 100 usecs */
211 static unsigned long max_sched_granularity_ns = 1000000000; /* 1 second */
212 static unsigned long min_wakeup_granularity_ns; /* 0 usecs */
213 static unsigned long max_wakeup_granularity_ns = 1000000000; /* 1 second */
214 #endif
215
216 static ctl_table kern_table[] = {
217 #ifdef CONFIG_SCHED_DEBUG
218 {
219 .ctl_name = CTL_UNNUMBERED,
220 .procname = "sched_granularity_ns",
221 .data = &sysctl_sched_granularity,
222 .maxlen = sizeof(unsigned int),
223 .mode = 0644,
224 .proc_handler = &proc_dointvec_minmax,
225 .strategy = &sysctl_intvec,
226 .extra1 = &min_sched_granularity_ns,
227 .extra2 = &max_sched_granularity_ns,
228 },
229 {
230 .ctl_name = CTL_UNNUMBERED,
231 .procname = "sched_wakeup_granularity_ns",
232 .data = &sysctl_sched_wakeup_granularity,
233 .maxlen = sizeof(unsigned int),
234 .mode = 0644,
235 .proc_handler = &proc_dointvec_minmax,
236 .strategy = &sysctl_intvec,
237 .extra1 = &min_wakeup_granularity_ns,
238 .extra2 = &max_wakeup_granularity_ns,
239 },
240 {
241 .ctl_name = CTL_UNNUMBERED,
242 .procname = "sched_batch_wakeup_granularity_ns",
243 .data = &sysctl_sched_batch_wakeup_granularity,
244 .maxlen = sizeof(unsigned int),
245 .mode = 0644,
246 .proc_handler = &proc_dointvec_minmax,
247 .strategy = &sysctl_intvec,
248 .extra1 = &min_wakeup_granularity_ns,
249 .extra2 = &max_wakeup_granularity_ns,
250 },
251 {
252 .ctl_name = CTL_UNNUMBERED,
253 .procname = "sched_stat_granularity_ns",
254 .data = &sysctl_sched_stat_granularity,
255 .maxlen = sizeof(unsigned int),
256 .mode = 0644,
257 .proc_handler = &proc_dointvec_minmax,
258 .strategy = &sysctl_intvec,
259 .extra1 = &min_wakeup_granularity_ns,
260 .extra2 = &max_wakeup_granularity_ns,
261 },
262 {
263 .ctl_name = CTL_UNNUMBERED,
264 .procname = "sched_runtime_limit_ns",
265 .data = &sysctl_sched_runtime_limit,
266 .maxlen = sizeof(unsigned int),
267 .mode = 0644,
268 .proc_handler = &proc_dointvec_minmax,
269 .strategy = &sysctl_intvec,
270 .extra1 = &min_sched_granularity_ns,
271 .extra2 = &max_sched_granularity_ns,
272 },
273 {
274 .ctl_name = CTL_UNNUMBERED,
275 .procname = "sched_child_runs_first",
276 .data = &sysctl_sched_child_runs_first,
277 .maxlen = sizeof(unsigned int),
278 .mode = 0644,
279 .proc_handler = &proc_dointvec,
280 },
281 {
282 .ctl_name = CTL_UNNUMBERED,
283 .procname = "sched_features",
284 .data = &sysctl_sched_features,
285 .maxlen = sizeof(unsigned int),
286 .mode = 0644,
287 .proc_handler = &proc_dointvec,
288 },
289 #endif
290 {
291 .ctl_name = KERN_PANIC,
292 .procname = "panic",
293 .data = &panic_timeout,
294 .maxlen = sizeof(int),
295 .mode = 0644,
296 .proc_handler = &proc_dointvec,
297 },
298 {
299 .ctl_name = KERN_CORE_USES_PID,
300 .procname = "core_uses_pid",
301 .data = &core_uses_pid,
302 .maxlen = sizeof(int),
303 .mode = 0644,
304 .proc_handler = &proc_dointvec,
305 },
306 {
307 .ctl_name = KERN_CORE_PATTERN,
308 .procname = "core_pattern",
309 .data = core_pattern,
310 .maxlen = CORENAME_MAX_SIZE,
311 .mode = 0644,
312 .proc_handler = &proc_dostring,
313 .strategy = &sysctl_string,
314 },
315 #ifdef CONFIG_PROC_SYSCTL
316 {
317 .ctl_name = KERN_TAINTED,
318 .procname = "tainted",
319 .data = &tainted,
320 .maxlen = sizeof(int),
321 .mode = 0644,
322 .proc_handler = &proc_dointvec_taint,
323 },
324 #endif
325 {
326 .ctl_name = KERN_CAP_BSET,
327 .procname = "cap-bound",
328 .data = &cap_bset,
329 .maxlen = sizeof(kernel_cap_t),
330 .mode = 0600,
331 .proc_handler = &proc_dointvec_bset,
332 },
333 #ifdef CONFIG_BLK_DEV_INITRD
334 {
335 .ctl_name = KERN_REALROOTDEV,
336 .procname = "real-root-dev",
337 .data = &real_root_dev,
338 .maxlen = sizeof(int),
339 .mode = 0644,
340 .proc_handler = &proc_dointvec,
341 },
342 #endif
343 #ifdef __sparc__
344 {
345 .ctl_name = KERN_SPARC_REBOOT,
346 .procname = "reboot-cmd",
347 .data = reboot_command,
348 .maxlen = 256,
349 .mode = 0644,
350 .proc_handler = &proc_dostring,
351 .strategy = &sysctl_string,
352 },
353 {
354 .ctl_name = KERN_SPARC_STOP_A,
355 .procname = "stop-a",
356 .data = &stop_a_enabled,
357 .maxlen = sizeof (int),
358 .mode = 0644,
359 .proc_handler = &proc_dointvec,
360 },
361 {
362 .ctl_name = KERN_SPARC_SCONS_PWROFF,
363 .procname = "scons-poweroff",
364 .data = &scons_pwroff,
365 .maxlen = sizeof (int),
366 .mode = 0644,
367 .proc_handler = &proc_dointvec,
368 },
369 #endif
370 #ifdef __hppa__
371 {
372 .ctl_name = KERN_HPPA_PWRSW,
373 .procname = "soft-power",
374 .data = &pwrsw_enabled,
375 .maxlen = sizeof (int),
376 .mode = 0644,
377 .proc_handler = &proc_dointvec,
378 },
379 {
380 .ctl_name = KERN_HPPA_UNALIGNED,
381 .procname = "unaligned-trap",
382 .data = &unaligned_enabled,
383 .maxlen = sizeof (int),
384 .mode = 0644,
385 .proc_handler = &proc_dointvec,
386 },
387 #endif
388 {
389 .ctl_name = KERN_CTLALTDEL,
390 .procname = "ctrl-alt-del",
391 .data = &C_A_D,
392 .maxlen = sizeof(int),
393 .mode = 0644,
394 .proc_handler = &proc_dointvec,
395 },
396 {
397 .ctl_name = KERN_PRINTK,
398 .procname = "printk",
399 .data = &console_loglevel,
400 .maxlen = 4*sizeof(int),
401 .mode = 0644,
402 .proc_handler = &proc_dointvec,
403 },
404 #ifdef CONFIG_KMOD
405 {
406 .ctl_name = KERN_MODPROBE,
407 .procname = "modprobe",
408 .data = &modprobe_path,
409 .maxlen = KMOD_PATH_LEN,
410 .mode = 0644,
411 .proc_handler = &proc_dostring,
412 .strategy = &sysctl_string,
413 },
414 #endif
415 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
416 {
417 .ctl_name = KERN_HOTPLUG,
418 .procname = "hotplug",
419 .data = &uevent_helper,
420 .maxlen = UEVENT_HELPER_PATH_LEN,
421 .mode = 0644,
422 .proc_handler = &proc_dostring,
423 .strategy = &sysctl_string,
424 },
425 #endif
426 #ifdef CONFIG_CHR_DEV_SG
427 {
428 .ctl_name = KERN_SG_BIG_BUFF,
429 .procname = "sg-big-buff",
430 .data = &sg_big_buff,
431 .maxlen = sizeof (int),
432 .mode = 0444,
433 .proc_handler = &proc_dointvec,
434 },
435 #endif
436 #ifdef CONFIG_BSD_PROCESS_ACCT
437 {
438 .ctl_name = KERN_ACCT,
439 .procname = "acct",
440 .data = &acct_parm,
441 .maxlen = 3*sizeof(int),
442 .mode = 0644,
443 .proc_handler = &proc_dointvec,
444 },
445 #endif
446 #ifdef CONFIG_MAGIC_SYSRQ
447 {
448 .ctl_name = KERN_SYSRQ,
449 .procname = "sysrq",
450 .data = &__sysrq_enabled,
451 .maxlen = sizeof (int),
452 .mode = 0644,
453 .proc_handler = &proc_dointvec,
454 },
455 #endif
456 #ifdef CONFIG_PROC_SYSCTL
457 {
458 .ctl_name = KERN_CADPID,
459 .procname = "cad_pid",
460 .data = NULL,
461 .maxlen = sizeof (int),
462 .mode = 0600,
463 .proc_handler = &proc_do_cad_pid,
464 },
465 #endif
466 {
467 .ctl_name = KERN_MAX_THREADS,
468 .procname = "threads-max",
469 .data = &max_threads,
470 .maxlen = sizeof(int),
471 .mode = 0644,
472 .proc_handler = &proc_dointvec,
473 },
474 {
475 .ctl_name = KERN_RANDOM,
476 .procname = "random",
477 .mode = 0555,
478 .child = random_table,
479 },
480 #ifdef CONFIG_UNIX98_PTYS
481 {
482 .ctl_name = KERN_PTY,
483 .procname = "pty",
484 .mode = 0555,
485 .child = pty_table,
486 },
487 #endif
488 {
489 .ctl_name = KERN_OVERFLOWUID,
490 .procname = "overflowuid",
491 .data = &overflowuid,
492 .maxlen = sizeof(int),
493 .mode = 0644,
494 .proc_handler = &proc_dointvec_minmax,
495 .strategy = &sysctl_intvec,
496 .extra1 = &minolduid,
497 .extra2 = &maxolduid,
498 },
499 {
500 .ctl_name = KERN_OVERFLOWGID,
501 .procname = "overflowgid",
502 .data = &overflowgid,
503 .maxlen = sizeof(int),
504 .mode = 0644,
505 .proc_handler = &proc_dointvec_minmax,
506 .strategy = &sysctl_intvec,
507 .extra1 = &minolduid,
508 .extra2 = &maxolduid,
509 },
510 #ifdef CONFIG_S390
511 #ifdef CONFIG_MATHEMU
512 {
513 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
514 .procname = "ieee_emulation_warnings",
515 .data = &sysctl_ieee_emulation_warnings,
516 .maxlen = sizeof(int),
517 .mode = 0644,
518 .proc_handler = &proc_dointvec,
519 },
520 #endif
521 #ifdef CONFIG_NO_IDLE_HZ
522 {
523 .ctl_name = KERN_HZ_TIMER,
524 .procname = "hz_timer",
525 .data = &sysctl_hz_timer,
526 .maxlen = sizeof(int),
527 .mode = 0644,
528 .proc_handler = &proc_dointvec,
529 },
530 #endif
531 {
532 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
533 .procname = "userprocess_debug",
534 .data = &sysctl_userprocess_debug,
535 .maxlen = sizeof(int),
536 .mode = 0644,
537 .proc_handler = &proc_dointvec,
538 },
539 #endif
540 {
541 .ctl_name = KERN_PIDMAX,
542 .procname = "pid_max",
543 .data = &pid_max,
544 .maxlen = sizeof (int),
545 .mode = 0644,
546 .proc_handler = &proc_dointvec_minmax,
547 .strategy = sysctl_intvec,
548 .extra1 = &pid_max_min,
549 .extra2 = &pid_max_max,
550 },
551 {
552 .ctl_name = KERN_PANIC_ON_OOPS,
553 .procname = "panic_on_oops",
554 .data = &panic_on_oops,
555 .maxlen = sizeof(int),
556 .mode = 0644,
557 .proc_handler = &proc_dointvec,
558 },
559 {
560 .ctl_name = KERN_PRINTK_RATELIMIT,
561 .procname = "printk_ratelimit",
562 .data = &printk_ratelimit_jiffies,
563 .maxlen = sizeof(int),
564 .mode = 0644,
565 .proc_handler = &proc_dointvec_jiffies,
566 .strategy = &sysctl_jiffies,
567 },
568 {
569 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
570 .procname = "printk_ratelimit_burst",
571 .data = &printk_ratelimit_burst,
572 .maxlen = sizeof(int),
573 .mode = 0644,
574 .proc_handler = &proc_dointvec,
575 },
576 {
577 .ctl_name = KERN_NGROUPS_MAX,
578 .procname = "ngroups_max",
579 .data = &ngroups_max,
580 .maxlen = sizeof (int),
581 .mode = 0444,
582 .proc_handler = &proc_dointvec,
583 },
584 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
585 {
586 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
587 .procname = "unknown_nmi_panic",
588 .data = &unknown_nmi_panic,
589 .maxlen = sizeof (int),
590 .mode = 0644,
591 .proc_handler = &proc_dointvec,
592 },
593 {
594 .ctl_name = KERN_NMI_WATCHDOG,
595 .procname = "nmi_watchdog",
596 .data = &nmi_watchdog_enabled,
597 .maxlen = sizeof (int),
598 .mode = 0644,
599 .proc_handler = &proc_nmi_enabled,
600 },
601 #endif
602 #if defined(CONFIG_X86)
603 {
604 .ctl_name = KERN_PANIC_ON_NMI,
605 .procname = "panic_on_unrecovered_nmi",
606 .data = &panic_on_unrecovered_nmi,
607 .maxlen = sizeof(int),
608 .mode = 0644,
609 .proc_handler = &proc_dointvec,
610 },
611 {
612 .ctl_name = KERN_BOOTLOADER_TYPE,
613 .procname = "bootloader_type",
614 .data = &bootloader_type,
615 .maxlen = sizeof (int),
616 .mode = 0444,
617 .proc_handler = &proc_dointvec,
618 },
619 {
620 .ctl_name = CTL_UNNUMBERED,
621 .procname = "kstack_depth_to_print",
622 .data = &kstack_depth_to_print,
623 .maxlen = sizeof(int),
624 .mode = 0644,
625 .proc_handler = &proc_dointvec,
626 },
627 #endif
628 #if defined(CONFIG_MMU)
629 {
630 .ctl_name = KERN_RANDOMIZE,
631 .procname = "randomize_va_space",
632 .data = &randomize_va_space,
633 .maxlen = sizeof(int),
634 .mode = 0644,
635 .proc_handler = &proc_dointvec,
636 },
637 #endif
638 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
639 {
640 .ctl_name = KERN_SPIN_RETRY,
641 .procname = "spin_retry",
642 .data = &spin_retry,
643 .maxlen = sizeof (int),
644 .mode = 0644,
645 .proc_handler = &proc_dointvec,
646 },
647 #endif
648 #ifdef CONFIG_ACPI_SLEEP
649 {
650 .ctl_name = KERN_ACPI_VIDEO_FLAGS,
651 .procname = "acpi_video_flags",
652 .data = &acpi_video_flags,
653 .maxlen = sizeof (unsigned long),
654 .mode = 0644,
655 .proc_handler = &proc_doulongvec_minmax,
656 },
657 #endif
658 #ifdef CONFIG_IA64
659 {
660 .ctl_name = KERN_IA64_UNALIGNED,
661 .procname = "ignore-unaligned-usertrap",
662 .data = &no_unaligned_warning,
663 .maxlen = sizeof (int),
664 .mode = 0644,
665 .proc_handler = &proc_dointvec,
666 },
667 #endif
668 #ifdef CONFIG_COMPAT
669 {
670 .ctl_name = KERN_COMPAT_LOG,
671 .procname = "compat-log",
672 .data = &compat_log,
673 .maxlen = sizeof (int),
674 .mode = 0644,
675 .proc_handler = &proc_dointvec,
676 },
677 #endif
678 #ifdef CONFIG_RT_MUTEXES
679 {
680 .ctl_name = KERN_MAX_LOCK_DEPTH,
681 .procname = "max_lock_depth",
682 .data = &max_lock_depth,
683 .maxlen = sizeof(int),
684 .mode = 0644,
685 .proc_handler = &proc_dointvec,
686 },
687 #endif
688 #ifdef CONFIG_PROC_FS
689 {
690 .ctl_name = CTL_UNNUMBERED,
691 .procname = "maps_protect",
692 .data = &maps_protect,
693 .maxlen = sizeof(int),
694 .mode = 0644,
695 .proc_handler = &proc_dointvec,
696 },
697 #endif
698
699 { .ctl_name = 0 }
700 };
701
702 /* Constants for minimum and maximum testing in vm_table.
703 We use these as one-element integer vectors. */
704 static int zero;
705 static int one_hundred = 100;
706
707
708 static ctl_table vm_table[] = {
709 {
710 .ctl_name = VM_OVERCOMMIT_MEMORY,
711 .procname = "overcommit_memory",
712 .data = &sysctl_overcommit_memory,
713 .maxlen = sizeof(sysctl_overcommit_memory),
714 .mode = 0644,
715 .proc_handler = &proc_dointvec,
716 },
717 {
718 .ctl_name = VM_PANIC_ON_OOM,
719 .procname = "panic_on_oom",
720 .data = &sysctl_panic_on_oom,
721 .maxlen = sizeof(sysctl_panic_on_oom),
722 .mode = 0644,
723 .proc_handler = &proc_dointvec,
724 },
725 {
726 .ctl_name = VM_OVERCOMMIT_RATIO,
727 .procname = "overcommit_ratio",
728 .data = &sysctl_overcommit_ratio,
729 .maxlen = sizeof(sysctl_overcommit_ratio),
730 .mode = 0644,
731 .proc_handler = &proc_dointvec,
732 },
733 {
734 .ctl_name = VM_PAGE_CLUSTER,
735 .procname = "page-cluster",
736 .data = &page_cluster,
737 .maxlen = sizeof(int),
738 .mode = 0644,
739 .proc_handler = &proc_dointvec,
740 },
741 {
742 .ctl_name = VM_DIRTY_BACKGROUND,
743 .procname = "dirty_background_ratio",
744 .data = &dirty_background_ratio,
745 .maxlen = sizeof(dirty_background_ratio),
746 .mode = 0644,
747 .proc_handler = &proc_dointvec_minmax,
748 .strategy = &sysctl_intvec,
749 .extra1 = &zero,
750 .extra2 = &one_hundred,
751 },
752 {
753 .ctl_name = VM_DIRTY_RATIO,
754 .procname = "dirty_ratio",
755 .data = &vm_dirty_ratio,
756 .maxlen = sizeof(vm_dirty_ratio),
757 .mode = 0644,
758 .proc_handler = &proc_dointvec_minmax,
759 .strategy = &sysctl_intvec,
760 .extra1 = &zero,
761 .extra2 = &one_hundred,
762 },
763 {
764 .ctl_name = VM_DIRTY_WB_CS,
765 .procname = "dirty_writeback_centisecs",
766 .data = &dirty_writeback_interval,
767 .maxlen = sizeof(dirty_writeback_interval),
768 .mode = 0644,
769 .proc_handler = &dirty_writeback_centisecs_handler,
770 },
771 {
772 .ctl_name = VM_DIRTY_EXPIRE_CS,
773 .procname = "dirty_expire_centisecs",
774 .data = &dirty_expire_interval,
775 .maxlen = sizeof(dirty_expire_interval),
776 .mode = 0644,
777 .proc_handler = &proc_dointvec_userhz_jiffies,
778 },
779 {
780 .ctl_name = VM_NR_PDFLUSH_THREADS,
781 .procname = "nr_pdflush_threads",
782 .data = &nr_pdflush_threads,
783 .maxlen = sizeof nr_pdflush_threads,
784 .mode = 0444 /* read-only*/,
785 .proc_handler = &proc_dointvec,
786 },
787 {
788 .ctl_name = VM_SWAPPINESS,
789 .procname = "swappiness",
790 .data = &vm_swappiness,
791 .maxlen = sizeof(vm_swappiness),
792 .mode = 0644,
793 .proc_handler = &proc_dointvec_minmax,
794 .strategy = &sysctl_intvec,
795 .extra1 = &zero,
796 .extra2 = &one_hundred,
797 },
798 #ifdef CONFIG_HUGETLB_PAGE
799 {
800 .ctl_name = VM_HUGETLB_PAGES,
801 .procname = "nr_hugepages",
802 .data = &max_huge_pages,
803 .maxlen = sizeof(unsigned long),
804 .mode = 0644,
805 .proc_handler = &hugetlb_sysctl_handler,
806 .extra1 = (void *)&hugetlb_zero,
807 .extra2 = (void *)&hugetlb_infinity,
808 },
809 {
810 .ctl_name = VM_HUGETLB_GROUP,
811 .procname = "hugetlb_shm_group",
812 .data = &sysctl_hugetlb_shm_group,
813 .maxlen = sizeof(gid_t),
814 .mode = 0644,
815 .proc_handler = &proc_dointvec,
816 },
817 #endif
818 {
819 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
820 .procname = "lowmem_reserve_ratio",
821 .data = &sysctl_lowmem_reserve_ratio,
822 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
823 .mode = 0644,
824 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
825 .strategy = &sysctl_intvec,
826 },
827 {
828 .ctl_name = VM_DROP_PAGECACHE,
829 .procname = "drop_caches",
830 .data = &sysctl_drop_caches,
831 .maxlen = sizeof(int),
832 .mode = 0644,
833 .proc_handler = drop_caches_sysctl_handler,
834 .strategy = &sysctl_intvec,
835 },
836 {
837 .ctl_name = VM_MIN_FREE_KBYTES,
838 .procname = "min_free_kbytes",
839 .data = &min_free_kbytes,
840 .maxlen = sizeof(min_free_kbytes),
841 .mode = 0644,
842 .proc_handler = &min_free_kbytes_sysctl_handler,
843 .strategy = &sysctl_intvec,
844 .extra1 = &zero,
845 },
846 {
847 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
848 .procname = "percpu_pagelist_fraction",
849 .data = &percpu_pagelist_fraction,
850 .maxlen = sizeof(percpu_pagelist_fraction),
851 .mode = 0644,
852 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
853 .strategy = &sysctl_intvec,
854 .extra1 = &min_percpu_pagelist_fract,
855 },
856 #ifdef CONFIG_MMU
857 {
858 .ctl_name = VM_MAX_MAP_COUNT,
859 .procname = "max_map_count",
860 .data = &sysctl_max_map_count,
861 .maxlen = sizeof(sysctl_max_map_count),
862 .mode = 0644,
863 .proc_handler = &proc_dointvec
864 },
865 #endif
866 {
867 .ctl_name = VM_LAPTOP_MODE,
868 .procname = "laptop_mode",
869 .data = &laptop_mode,
870 .maxlen = sizeof(laptop_mode),
871 .mode = 0644,
872 .proc_handler = &proc_dointvec_jiffies,
873 .strategy = &sysctl_jiffies,
874 },
875 {
876 .ctl_name = VM_BLOCK_DUMP,
877 .procname = "block_dump",
878 .data = &block_dump,
879 .maxlen = sizeof(block_dump),
880 .mode = 0644,
881 .proc_handler = &proc_dointvec,
882 .strategy = &sysctl_intvec,
883 .extra1 = &zero,
884 },
885 {
886 .ctl_name = VM_VFS_CACHE_PRESSURE,
887 .procname = "vfs_cache_pressure",
888 .data = &sysctl_vfs_cache_pressure,
889 .maxlen = sizeof(sysctl_vfs_cache_pressure),
890 .mode = 0644,
891 .proc_handler = &proc_dointvec,
892 .strategy = &sysctl_intvec,
893 .extra1 = &zero,
894 },
895 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
896 {
897 .ctl_name = VM_LEGACY_VA_LAYOUT,
898 .procname = "legacy_va_layout",
899 .data = &sysctl_legacy_va_layout,
900 .maxlen = sizeof(sysctl_legacy_va_layout),
901 .mode = 0644,
902 .proc_handler = &proc_dointvec,
903 .strategy = &sysctl_intvec,
904 .extra1 = &zero,
905 },
906 #endif
907 #ifdef CONFIG_NUMA
908 {
909 .ctl_name = VM_ZONE_RECLAIM_MODE,
910 .procname = "zone_reclaim_mode",
911 .data = &zone_reclaim_mode,
912 .maxlen = sizeof(zone_reclaim_mode),
913 .mode = 0644,
914 .proc_handler = &proc_dointvec,
915 .strategy = &sysctl_intvec,
916 .extra1 = &zero,
917 },
918 {
919 .ctl_name = VM_MIN_UNMAPPED,
920 .procname = "min_unmapped_ratio",
921 .data = &sysctl_min_unmapped_ratio,
922 .maxlen = sizeof(sysctl_min_unmapped_ratio),
923 .mode = 0644,
924 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
925 .strategy = &sysctl_intvec,
926 .extra1 = &zero,
927 .extra2 = &one_hundred,
928 },
929 {
930 .ctl_name = VM_MIN_SLAB,
931 .procname = "min_slab_ratio",
932 .data = &sysctl_min_slab_ratio,
933 .maxlen = sizeof(sysctl_min_slab_ratio),
934 .mode = 0644,
935 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
936 .strategy = &sysctl_intvec,
937 .extra1 = &zero,
938 .extra2 = &one_hundred,
939 },
940 #endif
941 #ifdef CONFIG_SMP
942 {
943 .ctl_name = CTL_UNNUMBERED,
944 .procname = "stat_interval",
945 .data = &sysctl_stat_interval,
946 .maxlen = sizeof(sysctl_stat_interval),
947 .mode = 0644,
948 .proc_handler = &proc_dointvec_jiffies,
949 .strategy = &sysctl_jiffies,
950 },
951 #endif
952 #if defined(CONFIG_X86_32) || \
953 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
954 {
955 .ctl_name = VM_VDSO_ENABLED,
956 .procname = "vdso_enabled",
957 .data = &vdso_enabled,
958 .maxlen = sizeof(vdso_enabled),
959 .mode = 0644,
960 .proc_handler = &proc_dointvec,
961 .strategy = &sysctl_intvec,
962 .extra1 = &zero,
963 },
964 #endif
965 { .ctl_name = 0 }
966 };
967
968 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
969 static ctl_table binfmt_misc_table[] = {
970 { .ctl_name = 0 }
971 };
972 #endif
973
974 static ctl_table fs_table[] = {
975 {
976 .ctl_name = FS_NRINODE,
977 .procname = "inode-nr",
978 .data = &inodes_stat,
979 .maxlen = 2*sizeof(int),
980 .mode = 0444,
981 .proc_handler = &proc_dointvec,
982 },
983 {
984 .ctl_name = FS_STATINODE,
985 .procname = "inode-state",
986 .data = &inodes_stat,
987 .maxlen = 7*sizeof(int),
988 .mode = 0444,
989 .proc_handler = &proc_dointvec,
990 },
991 {
992 .ctl_name = FS_NRFILE,
993 .procname = "file-nr",
994 .data = &files_stat,
995 .maxlen = 3*sizeof(int),
996 .mode = 0444,
997 .proc_handler = &proc_nr_files,
998 },
999 {
1000 .ctl_name = FS_MAXFILE,
1001 .procname = "file-max",
1002 .data = &files_stat.max_files,
1003 .maxlen = sizeof(int),
1004 .mode = 0644,
1005 .proc_handler = &proc_dointvec,
1006 },
1007 {
1008 .ctl_name = FS_DENTRY,
1009 .procname = "dentry-state",
1010 .data = &dentry_stat,
1011 .maxlen = 6*sizeof(int),
1012 .mode = 0444,
1013 .proc_handler = &proc_dointvec,
1014 },
1015 {
1016 .ctl_name = FS_OVERFLOWUID,
1017 .procname = "overflowuid",
1018 .data = &fs_overflowuid,
1019 .maxlen = sizeof(int),
1020 .mode = 0644,
1021 .proc_handler = &proc_dointvec_minmax,
1022 .strategy = &sysctl_intvec,
1023 .extra1 = &minolduid,
1024 .extra2 = &maxolduid,
1025 },
1026 {
1027 .ctl_name = FS_OVERFLOWGID,
1028 .procname = "overflowgid",
1029 .data = &fs_overflowgid,
1030 .maxlen = sizeof(int),
1031 .mode = 0644,
1032 .proc_handler = &proc_dointvec_minmax,
1033 .strategy = &sysctl_intvec,
1034 .extra1 = &minolduid,
1035 .extra2 = &maxolduid,
1036 },
1037 {
1038 .ctl_name = FS_LEASES,
1039 .procname = "leases-enable",
1040 .data = &leases_enable,
1041 .maxlen = sizeof(int),
1042 .mode = 0644,
1043 .proc_handler = &proc_dointvec,
1044 },
1045 #ifdef CONFIG_DNOTIFY
1046 {
1047 .ctl_name = FS_DIR_NOTIFY,
1048 .procname = "dir-notify-enable",
1049 .data = &dir_notify_enable,
1050 .maxlen = sizeof(int),
1051 .mode = 0644,
1052 .proc_handler = &proc_dointvec,
1053 },
1054 #endif
1055 #ifdef CONFIG_MMU
1056 {
1057 .ctl_name = FS_LEASE_TIME,
1058 .procname = "lease-break-time",
1059 .data = &lease_break_time,
1060 .maxlen = sizeof(int),
1061 .mode = 0644,
1062 .proc_handler = &proc_dointvec,
1063 },
1064 {
1065 .ctl_name = FS_AIO_NR,
1066 .procname = "aio-nr",
1067 .data = &aio_nr,
1068 .maxlen = sizeof(aio_nr),
1069 .mode = 0444,
1070 .proc_handler = &proc_doulongvec_minmax,
1071 },
1072 {
1073 .ctl_name = FS_AIO_MAX_NR,
1074 .procname = "aio-max-nr",
1075 .data = &aio_max_nr,
1076 .maxlen = sizeof(aio_max_nr),
1077 .mode = 0644,
1078 .proc_handler = &proc_doulongvec_minmax,
1079 },
1080 #ifdef CONFIG_INOTIFY_USER
1081 {
1082 .ctl_name = FS_INOTIFY,
1083 .procname = "inotify",
1084 .mode = 0555,
1085 .child = inotify_table,
1086 },
1087 #endif
1088 #endif
1089 {
1090 .ctl_name = KERN_SETUID_DUMPABLE,
1091 .procname = "suid_dumpable",
1092 .data = &suid_dumpable,
1093 .maxlen = sizeof(int),
1094 .mode = 0644,
1095 .proc_handler = &proc_dointvec,
1096 },
1097 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1098 {
1099 .ctl_name = CTL_UNNUMBERED,
1100 .procname = "binfmt_misc",
1101 .mode = 0555,
1102 .child = binfmt_misc_table,
1103 },
1104 #endif
1105 { .ctl_name = 0 }
1106 };
1107
1108 static ctl_table debug_table[] = {
1109 { .ctl_name = 0 }
1110 };
1111
1112 static ctl_table dev_table[] = {
1113 { .ctl_name = 0 }
1114 };
1115
1116 static DEFINE_SPINLOCK(sysctl_lock);
1117
1118 /* called under sysctl_lock */
1119 static int use_table(struct ctl_table_header *p)
1120 {
1121 if (unlikely(p->unregistering))
1122 return 0;
1123 p->used++;
1124 return 1;
1125 }
1126
1127 /* called under sysctl_lock */
1128 static void unuse_table(struct ctl_table_header *p)
1129 {
1130 if (!--p->used)
1131 if (unlikely(p->unregistering))
1132 complete(p->unregistering);
1133 }
1134
1135 /* called under sysctl_lock, will reacquire if has to wait */
1136 static void start_unregistering(struct ctl_table_header *p)
1137 {
1138 /*
1139 * if p->used is 0, nobody will ever touch that entry again;
1140 * we'll eliminate all paths to it before dropping sysctl_lock
1141 */
1142 if (unlikely(p->used)) {
1143 struct completion wait;
1144 init_completion(&wait);
1145 p->unregistering = &wait;
1146 spin_unlock(&sysctl_lock);
1147 wait_for_completion(&wait);
1148 spin_lock(&sysctl_lock);
1149 }
1150 /*
1151 * do not remove from the list until nobody holds it; walking the
1152 * list in do_sysctl() relies on that.
1153 */
1154 list_del_init(&p->ctl_entry);
1155 }
1156
1157 void sysctl_head_finish(struct ctl_table_header *head)
1158 {
1159 if (!head)
1160 return;
1161 spin_lock(&sysctl_lock);
1162 unuse_table(head);
1163 spin_unlock(&sysctl_lock);
1164 }
1165
1166 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1167 {
1168 struct ctl_table_header *head;
1169 struct list_head *tmp;
1170 spin_lock(&sysctl_lock);
1171 if (prev) {
1172 tmp = &prev->ctl_entry;
1173 unuse_table(prev);
1174 goto next;
1175 }
1176 tmp = &root_table_header.ctl_entry;
1177 for (;;) {
1178 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1179
1180 if (!use_table(head))
1181 goto next;
1182 spin_unlock(&sysctl_lock);
1183 return head;
1184 next:
1185 tmp = tmp->next;
1186 if (tmp == &root_table_header.ctl_entry)
1187 break;
1188 }
1189 spin_unlock(&sysctl_lock);
1190 return NULL;
1191 }
1192
1193 #ifdef CONFIG_SYSCTL_SYSCALL
1194 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1195 void __user *newval, size_t newlen)
1196 {
1197 struct ctl_table_header *head;
1198 int error = -ENOTDIR;
1199
1200 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1201 return -ENOTDIR;
1202 if (oldval) {
1203 int old_len;
1204 if (!oldlenp || get_user(old_len, oldlenp))
1205 return -EFAULT;
1206 }
1207
1208 for (head = sysctl_head_next(NULL); head;
1209 head = sysctl_head_next(head)) {
1210 error = parse_table(name, nlen, oldval, oldlenp,
1211 newval, newlen, head->ctl_table);
1212 if (error != -ENOTDIR) {
1213 sysctl_head_finish(head);
1214 break;
1215 }
1216 }
1217 return error;
1218 }
1219
1220 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1221 {
1222 struct __sysctl_args tmp;
1223 int error;
1224
1225 if (copy_from_user(&tmp, args, sizeof(tmp)))
1226 return -EFAULT;
1227
1228 lock_kernel();
1229 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1230 tmp.newval, tmp.newlen);
1231 unlock_kernel();
1232 return error;
1233 }
1234 #endif /* CONFIG_SYSCTL_SYSCALL */
1235
1236 /*
1237 * sysctl_perm does NOT grant the superuser all rights automatically, because
1238 * some sysctl variables are readonly even to root.
1239 */
1240
1241 static int test_perm(int mode, int op)
1242 {
1243 if (!current->euid)
1244 mode >>= 6;
1245 else if (in_egroup_p(0))
1246 mode >>= 3;
1247 if ((mode & op & 0007) == op)
1248 return 0;
1249 return -EACCES;
1250 }
1251
1252 int sysctl_perm(ctl_table *table, int op)
1253 {
1254 int error;
1255 error = security_sysctl(table, op);
1256 if (error)
1257 return error;
1258 return test_perm(table->mode, op);
1259 }
1260
1261 #ifdef CONFIG_SYSCTL_SYSCALL
1262 static int parse_table(int __user *name, int nlen,
1263 void __user *oldval, size_t __user *oldlenp,
1264 void __user *newval, size_t newlen,
1265 ctl_table *table)
1266 {
1267 int n;
1268 repeat:
1269 if (!nlen)
1270 return -ENOTDIR;
1271 if (get_user(n, name))
1272 return -EFAULT;
1273 for ( ; table->ctl_name || table->procname; table++) {
1274 if (!table->ctl_name)
1275 continue;
1276 if (n == table->ctl_name) {
1277 int error;
1278 if (table->child) {
1279 if (sysctl_perm(table, 001))
1280 return -EPERM;
1281 name++;
1282 nlen--;
1283 table = table->child;
1284 goto repeat;
1285 }
1286 error = do_sysctl_strategy(table, name, nlen,
1287 oldval, oldlenp,
1288 newval, newlen);
1289 return error;
1290 }
1291 }
1292 return -ENOTDIR;
1293 }
1294
1295 /* Perform the actual read/write of a sysctl table entry. */
1296 int do_sysctl_strategy (ctl_table *table,
1297 int __user *name, int nlen,
1298 void __user *oldval, size_t __user *oldlenp,
1299 void __user *newval, size_t newlen)
1300 {
1301 int op = 0, rc;
1302 size_t len;
1303
1304 if (oldval)
1305 op |= 004;
1306 if (newval)
1307 op |= 002;
1308 if (sysctl_perm(table, op))
1309 return -EPERM;
1310
1311 if (table->strategy) {
1312 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1313 newval, newlen);
1314 if (rc < 0)
1315 return rc;
1316 if (rc > 0)
1317 return 0;
1318 }
1319
1320 /* If there is no strategy routine, or if the strategy returns
1321 * zero, proceed with automatic r/w */
1322 if (table->data && table->maxlen) {
1323 if (oldval && oldlenp) {
1324 if (get_user(len, oldlenp))
1325 return -EFAULT;
1326 if (len) {
1327 if (len > table->maxlen)
1328 len = table->maxlen;
1329 if(copy_to_user(oldval, table->data, len))
1330 return -EFAULT;
1331 if(put_user(len, oldlenp))
1332 return -EFAULT;
1333 }
1334 }
1335 if (newval && newlen) {
1336 len = newlen;
1337 if (len > table->maxlen)
1338 len = table->maxlen;
1339 if(copy_from_user(table->data, newval, len))
1340 return -EFAULT;
1341 }
1342 }
1343 return 0;
1344 }
1345 #endif /* CONFIG_SYSCTL_SYSCALL */
1346
1347 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1348 {
1349 for (; table->ctl_name || table->procname; table++) {
1350 table->parent = parent;
1351 if (table->child)
1352 sysctl_set_parent(table, table->child);
1353 }
1354 }
1355
1356 static __init int sysctl_init(void)
1357 {
1358 sysctl_set_parent(NULL, root_table);
1359 return 0;
1360 }
1361
1362 core_initcall(sysctl_init);
1363
1364 /**
1365 * register_sysctl_table - register a sysctl hierarchy
1366 * @table: the top-level table structure
1367 *
1368 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1369 * array. An entry with a ctl_name of 0 terminates the table.
1370 *
1371 * The members of the &ctl_table structure are used as follows:
1372 *
1373 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1374 * must be unique within that level of sysctl
1375 *
1376 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1377 * enter a sysctl file
1378 *
1379 * data - a pointer to data for use by proc_handler
1380 *
1381 * maxlen - the maximum size in bytes of the data
1382 *
1383 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1384 *
1385 * child - a pointer to the child sysctl table if this entry is a directory, or
1386 * %NULL.
1387 *
1388 * proc_handler - the text handler routine (described below)
1389 *
1390 * strategy - the strategy routine (described below)
1391 *
1392 * de - for internal use by the sysctl routines
1393 *
1394 * extra1, extra2 - extra pointers usable by the proc handler routines
1395 *
1396 * Leaf nodes in the sysctl tree will be represented by a single file
1397 * under /proc; non-leaf nodes will be represented by directories.
1398 *
1399 * sysctl(2) can automatically manage read and write requests through
1400 * the sysctl table. The data and maxlen fields of the ctl_table
1401 * struct enable minimal validation of the values being written to be
1402 * performed, and the mode field allows minimal authentication.
1403 *
1404 * More sophisticated management can be enabled by the provision of a
1405 * strategy routine with the table entry. This will be called before
1406 * any automatic read or write of the data is performed.
1407 *
1408 * The strategy routine may return
1409 *
1410 * < 0 - Error occurred (error is passed to user process)
1411 *
1412 * 0 - OK - proceed with automatic read or write.
1413 *
1414 * > 0 - OK - read or write has been done by the strategy routine, so
1415 * return immediately.
1416 *
1417 * There must be a proc_handler routine for any terminal nodes
1418 * mirrored under /proc/sys (non-terminals are handled by a built-in
1419 * directory handler). Several default handlers are available to
1420 * cover common cases -
1421 *
1422 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1423 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1424 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1425 *
1426 * It is the handler's job to read the input buffer from user memory
1427 * and process it. The handler should return 0 on success.
1428 *
1429 * This routine returns %NULL on a failure to register, and a pointer
1430 * to the table header on success.
1431 */
1432 struct ctl_table_header *register_sysctl_table(ctl_table * table)
1433 {
1434 struct ctl_table_header *tmp;
1435 tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1436 if (!tmp)
1437 return NULL;
1438 tmp->ctl_table = table;
1439 INIT_LIST_HEAD(&tmp->ctl_entry);
1440 tmp->used = 0;
1441 tmp->unregistering = NULL;
1442 sysctl_set_parent(NULL, table);
1443 spin_lock(&sysctl_lock);
1444 list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1445 spin_unlock(&sysctl_lock);
1446 return tmp;
1447 }
1448
1449 /**
1450 * unregister_sysctl_table - unregister a sysctl table hierarchy
1451 * @header: the header returned from register_sysctl_table
1452 *
1453 * Unregisters the sysctl table and all children. proc entries may not
1454 * actually be removed until they are no longer used by anyone.
1455 */
1456 void unregister_sysctl_table(struct ctl_table_header * header)
1457 {
1458 might_sleep();
1459 spin_lock(&sysctl_lock);
1460 start_unregistering(header);
1461 spin_unlock(&sysctl_lock);
1462 kfree(header);
1463 }
1464
1465 #else /* !CONFIG_SYSCTL */
1466 struct ctl_table_header *register_sysctl_table(ctl_table * table)
1467 {
1468 return NULL;
1469 }
1470
1471 void unregister_sysctl_table(struct ctl_table_header * table)
1472 {
1473 }
1474
1475 #endif /* CONFIG_SYSCTL */
1476
1477 /*
1478 * /proc/sys support
1479 */
1480
1481 #ifdef CONFIG_PROC_SYSCTL
1482
1483 static int _proc_do_string(void* data, int maxlen, int write,
1484 struct file *filp, void __user *buffer,
1485 size_t *lenp, loff_t *ppos)
1486 {
1487 size_t len;
1488 char __user *p;
1489 char c;
1490
1491 if (!data || !maxlen || !*lenp) {
1492 *lenp = 0;
1493 return 0;
1494 }
1495
1496 if (write) {
1497 len = 0;
1498 p = buffer;
1499 while (len < *lenp) {
1500 if (get_user(c, p++))
1501 return -EFAULT;
1502 if (c == 0 || c == '\n')
1503 break;
1504 len++;
1505 }
1506 if (len >= maxlen)
1507 len = maxlen-1;
1508 if(copy_from_user(data, buffer, len))
1509 return -EFAULT;
1510 ((char *) data)[len] = 0;
1511 *ppos += *lenp;
1512 } else {
1513 len = strlen(data);
1514 if (len > maxlen)
1515 len = maxlen;
1516
1517 if (*ppos > len) {
1518 *lenp = 0;
1519 return 0;
1520 }
1521
1522 data += *ppos;
1523 len -= *ppos;
1524
1525 if (len > *lenp)
1526 len = *lenp;
1527 if (len)
1528 if(copy_to_user(buffer, data, len))
1529 return -EFAULT;
1530 if (len < *lenp) {
1531 if(put_user('\n', ((char __user *) buffer) + len))
1532 return -EFAULT;
1533 len++;
1534 }
1535 *lenp = len;
1536 *ppos += len;
1537 }
1538 return 0;
1539 }
1540
1541 /**
1542 * proc_dostring - read a string sysctl
1543 * @table: the sysctl table
1544 * @write: %TRUE if this is a write to the sysctl file
1545 * @filp: the file structure
1546 * @buffer: the user buffer
1547 * @lenp: the size of the user buffer
1548 * @ppos: file position
1549 *
1550 * Reads/writes a string from/to the user buffer. If the kernel
1551 * buffer provided is not large enough to hold the string, the
1552 * string is truncated. The copied string is %NULL-terminated.
1553 * If the string is being read by the user process, it is copied
1554 * and a newline '\n' is added. It is truncated if the buffer is
1555 * not large enough.
1556 *
1557 * Returns 0 on success.
1558 */
1559 int proc_dostring(ctl_table *table, int write, struct file *filp,
1560 void __user *buffer, size_t *lenp, loff_t *ppos)
1561 {
1562 return _proc_do_string(table->data, table->maxlen, write, filp,
1563 buffer, lenp, ppos);
1564 }
1565
1566
1567 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1568 int *valp,
1569 int write, void *data)
1570 {
1571 if (write) {
1572 *valp = *negp ? -*lvalp : *lvalp;
1573 } else {
1574 int val = *valp;
1575 if (val < 0) {
1576 *negp = -1;
1577 *lvalp = (unsigned long)-val;
1578 } else {
1579 *negp = 0;
1580 *lvalp = (unsigned long)val;
1581 }
1582 }
1583 return 0;
1584 }
1585
1586 static int __do_proc_dointvec(void *tbl_data, ctl_table *table,
1587 int write, struct file *filp, void __user *buffer,
1588 size_t *lenp, loff_t *ppos,
1589 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1590 int write, void *data),
1591 void *data)
1592 {
1593 #define TMPBUFLEN 21
1594 int *i, vleft, first=1, neg, val;
1595 unsigned long lval;
1596 size_t left, len;
1597
1598 char buf[TMPBUFLEN], *p;
1599 char __user *s = buffer;
1600
1601 if (!tbl_data || !table->maxlen || !*lenp ||
1602 (*ppos && !write)) {
1603 *lenp = 0;
1604 return 0;
1605 }
1606
1607 i = (int *) tbl_data;
1608 vleft = table->maxlen / sizeof(*i);
1609 left = *lenp;
1610
1611 if (!conv)
1612 conv = do_proc_dointvec_conv;
1613
1614 for (; left && vleft--; i++, first=0) {
1615 if (write) {
1616 while (left) {
1617 char c;
1618 if (get_user(c, s))
1619 return -EFAULT;
1620 if (!isspace(c))
1621 break;
1622 left--;
1623 s++;
1624 }
1625 if (!left)
1626 break;
1627 neg = 0;
1628 len = left;
1629 if (len > sizeof(buf) - 1)
1630 len = sizeof(buf) - 1;
1631 if (copy_from_user(buf, s, len))
1632 return -EFAULT;
1633 buf[len] = 0;
1634 p = buf;
1635 if (*p == '-' && left > 1) {
1636 neg = 1;
1637 p++;
1638 }
1639 if (*p < '0' || *p > '9')
1640 break;
1641
1642 lval = simple_strtoul(p, &p, 0);
1643
1644 len = p-buf;
1645 if ((len < left) && *p && !isspace(*p))
1646 break;
1647 if (neg)
1648 val = -val;
1649 s += len;
1650 left -= len;
1651
1652 if (conv(&neg, &lval, i, 1, data))
1653 break;
1654 } else {
1655 p = buf;
1656 if (!first)
1657 *p++ = '\t';
1658
1659 if (conv(&neg, &lval, i, 0, data))
1660 break;
1661
1662 sprintf(p, "%s%lu", neg ? "-" : "", lval);
1663 len = strlen(buf);
1664 if (len > left)
1665 len = left;
1666 if(copy_to_user(s, buf, len))
1667 return -EFAULT;
1668 left -= len;
1669 s += len;
1670 }
1671 }
1672
1673 if (!write && !first && left) {
1674 if(put_user('\n', s))
1675 return -EFAULT;
1676 left--, s++;
1677 }
1678 if (write) {
1679 while (left) {
1680 char c;
1681 if (get_user(c, s++))
1682 return -EFAULT;
1683 if (!isspace(c))
1684 break;
1685 left--;
1686 }
1687 }
1688 if (write && first)
1689 return -EINVAL;
1690 *lenp -= left;
1691 *ppos += *lenp;
1692 return 0;
1693 #undef TMPBUFLEN
1694 }
1695
1696 static int do_proc_dointvec(ctl_table *table, int write, struct file *filp,
1697 void __user *buffer, size_t *lenp, loff_t *ppos,
1698 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1699 int write, void *data),
1700 void *data)
1701 {
1702 return __do_proc_dointvec(table->data, table, write, filp,
1703 buffer, lenp, ppos, conv, data);
1704 }
1705
1706 /**
1707 * proc_dointvec - read a vector of integers
1708 * @table: the sysctl table
1709 * @write: %TRUE if this is a write to the sysctl file
1710 * @filp: the file structure
1711 * @buffer: the user buffer
1712 * @lenp: the size of the user buffer
1713 * @ppos: file position
1714 *
1715 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1716 * values from/to the user buffer, treated as an ASCII string.
1717 *
1718 * Returns 0 on success.
1719 */
1720 int proc_dointvec(ctl_table *table, int write, struct file *filp,
1721 void __user *buffer, size_t *lenp, loff_t *ppos)
1722 {
1723 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1724 NULL,NULL);
1725 }
1726
1727 #define OP_SET 0
1728 #define OP_AND 1
1729 #define OP_OR 2
1730
1731 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1732 int *valp,
1733 int write, void *data)
1734 {
1735 int op = *(int *)data;
1736 if (write) {
1737 int val = *negp ? -*lvalp : *lvalp;
1738 switch(op) {
1739 case OP_SET: *valp = val; break;
1740 case OP_AND: *valp &= val; break;
1741 case OP_OR: *valp |= val; break;
1742 }
1743 } else {
1744 int val = *valp;
1745 if (val < 0) {
1746 *negp = -1;
1747 *lvalp = (unsigned long)-val;
1748 } else {
1749 *negp = 0;
1750 *lvalp = (unsigned long)val;
1751 }
1752 }
1753 return 0;
1754 }
1755
1756 /*
1757 * init may raise the set.
1758 */
1759
1760 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
1761 void __user *buffer, size_t *lenp, loff_t *ppos)
1762 {
1763 int op;
1764
1765 if (write && !capable(CAP_SYS_MODULE)) {
1766 return -EPERM;
1767 }
1768
1769 op = is_init(current) ? OP_SET : OP_AND;
1770 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1771 do_proc_dointvec_bset_conv,&op);
1772 }
1773
1774 /*
1775 * Taint values can only be increased
1776 */
1777 static int proc_dointvec_taint(ctl_table *table, int write, struct file *filp,
1778 void __user *buffer, size_t *lenp, loff_t *ppos)
1779 {
1780 int op;
1781
1782 if (write && !capable(CAP_SYS_ADMIN))
1783 return -EPERM;
1784
1785 op = OP_OR;
1786 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1787 do_proc_dointvec_bset_conv,&op);
1788 }
1789
1790 struct do_proc_dointvec_minmax_conv_param {
1791 int *min;
1792 int *max;
1793 };
1794
1795 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
1796 int *valp,
1797 int write, void *data)
1798 {
1799 struct do_proc_dointvec_minmax_conv_param *param = data;
1800 if (write) {
1801 int val = *negp ? -*lvalp : *lvalp;
1802 if ((param->min && *param->min > val) ||
1803 (param->max && *param->max < val))
1804 return -EINVAL;
1805 *valp = val;
1806 } else {
1807 int val = *valp;
1808 if (val < 0) {
1809 *negp = -1;
1810 *lvalp = (unsigned long)-val;
1811 } else {
1812 *negp = 0;
1813 *lvalp = (unsigned long)val;
1814 }
1815 }
1816 return 0;
1817 }
1818
1819 /**
1820 * proc_dointvec_minmax - read a vector of integers with min/max values
1821 * @table: the sysctl table
1822 * @write: %TRUE if this is a write to the sysctl file
1823 * @filp: the file structure
1824 * @buffer: the user buffer
1825 * @lenp: the size of the user buffer
1826 * @ppos: file position
1827 *
1828 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1829 * values from/to the user buffer, treated as an ASCII string.
1830 *
1831 * This routine will ensure the values are within the range specified by
1832 * table->extra1 (min) and table->extra2 (max).
1833 *
1834 * Returns 0 on success.
1835 */
1836 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
1837 void __user *buffer, size_t *lenp, loff_t *ppos)
1838 {
1839 struct do_proc_dointvec_minmax_conv_param param = {
1840 .min = (int *) table->extra1,
1841 .max = (int *) table->extra2,
1842 };
1843 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1844 do_proc_dointvec_minmax_conv, &param);
1845 }
1846
1847 static int __do_proc_doulongvec_minmax(void *data, ctl_table *table, int write,
1848 struct file *filp,
1849 void __user *buffer,
1850 size_t *lenp, loff_t *ppos,
1851 unsigned long convmul,
1852 unsigned long convdiv)
1853 {
1854 #define TMPBUFLEN 21
1855 unsigned long *i, *min, *max, val;
1856 int vleft, first=1, neg;
1857 size_t len, left;
1858 char buf[TMPBUFLEN], *p;
1859 char __user *s = buffer;
1860
1861 if (!data || !table->maxlen || !*lenp ||
1862 (*ppos && !write)) {
1863 *lenp = 0;
1864 return 0;
1865 }
1866
1867 i = (unsigned long *) data;
1868 min = (unsigned long *) table->extra1;
1869 max = (unsigned long *) table->extra2;
1870 vleft = table->maxlen / sizeof(unsigned long);
1871 left = *lenp;
1872
1873 for (; left && vleft--; i++, min++, max++, first=0) {
1874 if (write) {
1875 while (left) {
1876 char c;
1877 if (get_user(c, s))
1878 return -EFAULT;
1879 if (!isspace(c))
1880 break;
1881 left--;
1882 s++;
1883 }
1884 if (!left)
1885 break;
1886 neg = 0;
1887 len = left;
1888 if (len > TMPBUFLEN-1)
1889 len = TMPBUFLEN-1;
1890 if (copy_from_user(buf, s, len))
1891 return -EFAULT;
1892 buf[len] = 0;
1893 p = buf;
1894 if (*p == '-' && left > 1) {
1895 neg = 1;
1896 p++;
1897 }
1898 if (*p < '0' || *p > '9')
1899 break;
1900 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
1901 len = p-buf;
1902 if ((len < left) && *p && !isspace(*p))
1903 break;
1904 if (neg)
1905 val = -val;
1906 s += len;
1907 left -= len;
1908
1909 if(neg)
1910 continue;
1911 if ((min && val < *min) || (max && val > *max))
1912 continue;
1913 *i = val;
1914 } else {
1915 p = buf;
1916 if (!first)
1917 *p++ = '\t';
1918 sprintf(p, "%lu", convdiv * (*i) / convmul);
1919 len = strlen(buf);
1920 if (len > left)
1921 len = left;
1922 if(copy_to_user(s, buf, len))
1923 return -EFAULT;
1924 left -= len;
1925 s += len;
1926 }
1927 }
1928
1929 if (!write && !first && left) {
1930 if(put_user('\n', s))
1931 return -EFAULT;
1932 left--, s++;
1933 }
1934 if (write) {
1935 while (left) {
1936 char c;
1937 if (get_user(c, s++))
1938 return -EFAULT;
1939 if (!isspace(c))
1940 break;
1941 left--;
1942 }
1943 }
1944 if (write && first)
1945 return -EINVAL;
1946 *lenp -= left;
1947 *ppos += *lenp;
1948 return 0;
1949 #undef TMPBUFLEN
1950 }
1951
1952 static int do_proc_doulongvec_minmax(ctl_table *table, int write,
1953 struct file *filp,
1954 void __user *buffer,
1955 size_t *lenp, loff_t *ppos,
1956 unsigned long convmul,
1957 unsigned long convdiv)
1958 {
1959 return __do_proc_doulongvec_minmax(table->data, table, write,
1960 filp, buffer, lenp, ppos, convmul, convdiv);
1961 }
1962
1963 /**
1964 * proc_doulongvec_minmax - read a vector of long integers with min/max values
1965 * @table: the sysctl table
1966 * @write: %TRUE if this is a write to the sysctl file
1967 * @filp: the file structure
1968 * @buffer: the user buffer
1969 * @lenp: the size of the user buffer
1970 * @ppos: file position
1971 *
1972 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1973 * values from/to the user buffer, treated as an ASCII string.
1974 *
1975 * This routine will ensure the values are within the range specified by
1976 * table->extra1 (min) and table->extra2 (max).
1977 *
1978 * Returns 0 on success.
1979 */
1980 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
1981 void __user *buffer, size_t *lenp, loff_t *ppos)
1982 {
1983 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
1984 }
1985
1986 /**
1987 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1988 * @table: the sysctl table
1989 * @write: %TRUE if this is a write to the sysctl file
1990 * @filp: the file structure
1991 * @buffer: the user buffer
1992 * @lenp: the size of the user buffer
1993 * @ppos: file position
1994 *
1995 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1996 * values from/to the user buffer, treated as an ASCII string. The values
1997 * are treated as milliseconds, and converted to jiffies when they are stored.
1998 *
1999 * This routine will ensure the values are within the range specified by
2000 * table->extra1 (min) and table->extra2 (max).
2001 *
2002 * Returns 0 on success.
2003 */
2004 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2005 struct file *filp,
2006 void __user *buffer,
2007 size_t *lenp, loff_t *ppos)
2008 {
2009 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2010 lenp, ppos, HZ, 1000l);
2011 }
2012
2013
2014 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2015 int *valp,
2016 int write, void *data)
2017 {
2018 if (write) {
2019 if (*lvalp > LONG_MAX / HZ)
2020 return 1;
2021 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2022 } else {
2023 int val = *valp;
2024 unsigned long lval;
2025 if (val < 0) {
2026 *negp = -1;
2027 lval = (unsigned long)-val;
2028 } else {
2029 *negp = 0;
2030 lval = (unsigned long)val;
2031 }
2032 *lvalp = lval / HZ;
2033 }
2034 return 0;
2035 }
2036
2037 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2038 int *valp,
2039 int write, void *data)
2040 {
2041 if (write) {
2042 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2043 return 1;
2044 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2045 } else {
2046 int val = *valp;
2047 unsigned long lval;
2048 if (val < 0) {
2049 *negp = -1;
2050 lval = (unsigned long)-val;
2051 } else {
2052 *negp = 0;
2053 lval = (unsigned long)val;
2054 }
2055 *lvalp = jiffies_to_clock_t(lval);
2056 }
2057 return 0;
2058 }
2059
2060 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2061 int *valp,
2062 int write, void *data)
2063 {
2064 if (write) {
2065 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2066 } else {
2067 int val = *valp;
2068 unsigned long lval;
2069 if (val < 0) {
2070 *negp = -1;
2071 lval = (unsigned long)-val;
2072 } else {
2073 *negp = 0;
2074 lval = (unsigned long)val;
2075 }
2076 *lvalp = jiffies_to_msecs(lval);
2077 }
2078 return 0;
2079 }
2080
2081 /**
2082 * proc_dointvec_jiffies - read a vector of integers as seconds
2083 * @table: the sysctl table
2084 * @write: %TRUE if this is a write to the sysctl file
2085 * @filp: the file structure
2086 * @buffer: the user buffer
2087 * @lenp: the size of the user buffer
2088 * @ppos: file position
2089 *
2090 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2091 * values from/to the user buffer, treated as an ASCII string.
2092 * The values read are assumed to be in seconds, and are converted into
2093 * jiffies.
2094 *
2095 * Returns 0 on success.
2096 */
2097 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2098 void __user *buffer, size_t *lenp, loff_t *ppos)
2099 {
2100 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2101 do_proc_dointvec_jiffies_conv,NULL);
2102 }
2103
2104 /**
2105 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2106 * @table: the sysctl table
2107 * @write: %TRUE if this is a write to the sysctl file
2108 * @filp: the file structure
2109 * @buffer: the user buffer
2110 * @lenp: the size of the user buffer
2111 * @ppos: pointer to the file position
2112 *
2113 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2114 * values from/to the user buffer, treated as an ASCII string.
2115 * The values read are assumed to be in 1/USER_HZ seconds, and
2116 * are converted into jiffies.
2117 *
2118 * Returns 0 on success.
2119 */
2120 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2121 void __user *buffer, size_t *lenp, loff_t *ppos)
2122 {
2123 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2124 do_proc_dointvec_userhz_jiffies_conv,NULL);
2125 }
2126
2127 /**
2128 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2129 * @table: the sysctl table
2130 * @write: %TRUE if this is a write to the sysctl file
2131 * @filp: the file structure
2132 * @buffer: the user buffer
2133 * @lenp: the size of the user buffer
2134 * @ppos: file position
2135 * @ppos: the current position in the file
2136 *
2137 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2138 * values from/to the user buffer, treated as an ASCII string.
2139 * The values read are assumed to be in 1/1000 seconds, and
2140 * are converted into jiffies.
2141 *
2142 * Returns 0 on success.
2143 */
2144 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2145 void __user *buffer, size_t *lenp, loff_t *ppos)
2146 {
2147 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2148 do_proc_dointvec_ms_jiffies_conv, NULL);
2149 }
2150
2151 static int proc_do_cad_pid(ctl_table *table, int write, struct file *filp,
2152 void __user *buffer, size_t *lenp, loff_t *ppos)
2153 {
2154 struct pid *new_pid;
2155 pid_t tmp;
2156 int r;
2157
2158 tmp = pid_nr(cad_pid);
2159
2160 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2161 lenp, ppos, NULL, NULL);
2162 if (r || !write)
2163 return r;
2164
2165 new_pid = find_get_pid(tmp);
2166 if (!new_pid)
2167 return -ESRCH;
2168
2169 put_pid(xchg(&cad_pid, new_pid));
2170 return 0;
2171 }
2172
2173 #else /* CONFIG_PROC_FS */
2174
2175 int proc_dostring(ctl_table *table, int write, struct file *filp,
2176 void __user *buffer, size_t *lenp, loff_t *ppos)
2177 {
2178 return -ENOSYS;
2179 }
2180
2181 int proc_dointvec(ctl_table *table, int write, struct file *filp,
2182 void __user *buffer, size_t *lenp, loff_t *ppos)
2183 {
2184 return -ENOSYS;
2185 }
2186
2187 int proc_dointvec_bset(ctl_table *table, int write, struct file *filp,
2188 void __user *buffer, size_t *lenp, loff_t *ppos)
2189 {
2190 return -ENOSYS;
2191 }
2192
2193 int proc_dointvec_minmax(ctl_table *table, int write, struct file *filp,
2194 void __user *buffer, size_t *lenp, loff_t *ppos)
2195 {
2196 return -ENOSYS;
2197 }
2198
2199 int proc_dointvec_jiffies(ctl_table *table, int write, struct file *filp,
2200 void __user *buffer, size_t *lenp, loff_t *ppos)
2201 {
2202 return -ENOSYS;
2203 }
2204
2205 int proc_dointvec_userhz_jiffies(ctl_table *table, int write, struct file *filp,
2206 void __user *buffer, size_t *lenp, loff_t *ppos)
2207 {
2208 return -ENOSYS;
2209 }
2210
2211 int proc_dointvec_ms_jiffies(ctl_table *table, int write, struct file *filp,
2212 void __user *buffer, size_t *lenp, loff_t *ppos)
2213 {
2214 return -ENOSYS;
2215 }
2216
2217 int proc_doulongvec_minmax(ctl_table *table, int write, struct file *filp,
2218 void __user *buffer, size_t *lenp, loff_t *ppos)
2219 {
2220 return -ENOSYS;
2221 }
2222
2223 int proc_doulongvec_ms_jiffies_minmax(ctl_table *table, int write,
2224 struct file *filp,
2225 void __user *buffer,
2226 size_t *lenp, loff_t *ppos)
2227 {
2228 return -ENOSYS;
2229 }
2230
2231
2232 #endif /* CONFIG_PROC_FS */
2233
2234
2235 #ifdef CONFIG_SYSCTL_SYSCALL
2236 /*
2237 * General sysctl support routines
2238 */
2239
2240 /* The generic string strategy routine: */
2241 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2242 void __user *oldval, size_t __user *oldlenp,
2243 void __user *newval, size_t newlen)
2244 {
2245 if (!table->data || !table->maxlen)
2246 return -ENOTDIR;
2247
2248 if (oldval && oldlenp) {
2249 size_t bufsize;
2250 if (get_user(bufsize, oldlenp))
2251 return -EFAULT;
2252 if (bufsize) {
2253 size_t len = strlen(table->data), copied;
2254
2255 /* This shouldn't trigger for a well-formed sysctl */
2256 if (len > table->maxlen)
2257 len = table->maxlen;
2258
2259 /* Copy up to a max of bufsize-1 bytes of the string */
2260 copied = (len >= bufsize) ? bufsize - 1 : len;
2261
2262 if (copy_to_user(oldval, table->data, copied) ||
2263 put_user(0, (char __user *)(oldval + copied)))
2264 return -EFAULT;
2265 if (put_user(len, oldlenp))
2266 return -EFAULT;
2267 }
2268 }
2269 if (newval && newlen) {
2270 size_t len = newlen;
2271 if (len > table->maxlen)
2272 len = table->maxlen;
2273 if(copy_from_user(table->data, newval, len))
2274 return -EFAULT;
2275 if (len == table->maxlen)
2276 len--;
2277 ((char *) table->data)[len] = 0;
2278 }
2279 return 1;
2280 }
2281
2282 /*
2283 * This function makes sure that all of the integers in the vector
2284 * are between the minimum and maximum values given in the arrays
2285 * table->extra1 and table->extra2, respectively.
2286 */
2287 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2288 void __user *oldval, size_t __user *oldlenp,
2289 void __user *newval, size_t newlen)
2290 {
2291
2292 if (newval && newlen) {
2293 int __user *vec = (int __user *) newval;
2294 int *min = (int *) table->extra1;
2295 int *max = (int *) table->extra2;
2296 size_t length;
2297 int i;
2298
2299 if (newlen % sizeof(int) != 0)
2300 return -EINVAL;
2301
2302 if (!table->extra1 && !table->extra2)
2303 return 0;
2304
2305 if (newlen > table->maxlen)
2306 newlen = table->maxlen;
2307 length = newlen / sizeof(int);
2308
2309 for (i = 0; i < length; i++) {
2310 int value;
2311 if (get_user(value, vec + i))
2312 return -EFAULT;
2313 if (min && value < min[i])
2314 return -EINVAL;
2315 if (max && value > max[i])
2316 return -EINVAL;
2317 }
2318 }
2319 return 0;
2320 }
2321
2322 /* Strategy function to convert jiffies to seconds */
2323 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2324 void __user *oldval, size_t __user *oldlenp,
2325 void __user *newval, size_t newlen)
2326 {
2327 if (oldval && oldlenp) {
2328 size_t olen;
2329
2330 if (get_user(olen, oldlenp))
2331 return -EFAULT;
2332 if (olen) {
2333 int val;
2334
2335 if (olen < sizeof(int))
2336 return -EINVAL;
2337
2338 val = *(int *)(table->data) / HZ;
2339 if (put_user(val, (int __user *)oldval))
2340 return -EFAULT;
2341 if (put_user(sizeof(int), oldlenp))
2342 return -EFAULT;
2343 }
2344 }
2345 if (newval && newlen) {
2346 int new;
2347 if (newlen != sizeof(int))
2348 return -EINVAL;
2349 if (get_user(new, (int __user *)newval))
2350 return -EFAULT;
2351 *(int *)(table->data) = new*HZ;
2352 }
2353 return 1;
2354 }
2355
2356 /* Strategy function to convert jiffies to seconds */
2357 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2358 void __user *oldval, size_t __user *oldlenp,
2359 void __user *newval, size_t newlen)
2360 {
2361 if (oldval && oldlenp) {
2362 size_t olen;
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 = jiffies_to_msecs(*(int *)(table->data));
2373 if (put_user(val, (int __user *)oldval))
2374 return -EFAULT;
2375 if (put_user(sizeof(int), oldlenp))
2376 return -EFAULT;
2377 }
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) = msecs_to_jiffies(new);
2386 }
2387 return 1;
2388 }
2389
2390
2391
2392 #else /* CONFIG_SYSCTL_SYSCALL */
2393
2394
2395 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2396 {
2397 static int msg_count;
2398 struct __sysctl_args tmp;
2399 int name[CTL_MAXNAME];
2400 int i;
2401
2402 /* Read in the sysctl name for better debug message logging */
2403 if (copy_from_user(&tmp, args, sizeof(tmp)))
2404 return -EFAULT;
2405 if (tmp.nlen <= 0 || tmp.nlen >= CTL_MAXNAME)
2406 return -ENOTDIR;
2407 for (i = 0; i < tmp.nlen; i++)
2408 if (get_user(name[i], tmp.name + i))
2409 return -EFAULT;
2410
2411 /* Ignore accesses to kernel.version */
2412 if ((tmp.nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2413 goto out;
2414
2415 if (msg_count < 5) {
2416 msg_count++;
2417 printk(KERN_INFO
2418 "warning: process `%s' used the removed sysctl "
2419 "system call with ", current->comm);
2420 for (i = 0; i < tmp.nlen; i++)
2421 printk("%d.", name[i]);
2422 printk("\n");
2423 }
2424 out:
2425 return -ENOSYS;
2426 }
2427
2428 int sysctl_string(ctl_table *table, int __user *name, int nlen,
2429 void __user *oldval, size_t __user *oldlenp,
2430 void __user *newval, size_t newlen)
2431 {
2432 return -ENOSYS;
2433 }
2434
2435 int sysctl_intvec(ctl_table *table, int __user *name, int nlen,
2436 void __user *oldval, size_t __user *oldlenp,
2437 void __user *newval, size_t newlen)
2438 {
2439 return -ENOSYS;
2440 }
2441
2442 int sysctl_jiffies(ctl_table *table, int __user *name, int nlen,
2443 void __user *oldval, size_t __user *oldlenp,
2444 void __user *newval, size_t newlen)
2445 {
2446 return -ENOSYS;
2447 }
2448
2449 int sysctl_ms_jiffies(ctl_table *table, int __user *name, int nlen,
2450 void __user *oldval, size_t __user *oldlenp,
2451 void __user *newval, size_t newlen)
2452 {
2453 return -ENOSYS;
2454 }
2455
2456 #endif /* CONFIG_SYSCTL_SYSCALL */
2457
2458 /*
2459 * No sense putting this after each symbol definition, twice,
2460 * exception granted :-)
2461 */
2462 EXPORT_SYMBOL(proc_dointvec);
2463 EXPORT_SYMBOL(proc_dointvec_jiffies);
2464 EXPORT_SYMBOL(proc_dointvec_minmax);
2465 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2466 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2467 EXPORT_SYMBOL(proc_dostring);
2468 EXPORT_SYMBOL(proc_doulongvec_minmax);
2469 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2470 EXPORT_SYMBOL(register_sysctl_table);
2471 EXPORT_SYMBOL(sysctl_intvec);
2472 EXPORT_SYMBOL(sysctl_jiffies);
2473 EXPORT_SYMBOL(sysctl_ms_jiffies);
2474 EXPORT_SYMBOL(sysctl_string);
2475 EXPORT_SYMBOL(unregister_sysctl_table);
Linux 2.6 ibm-acpi/thinkpad-acpi driver git tree