Merge branch 'x86/rdrand' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
[wandboard.git] / kernel / sysctl.c
blobf487f257e05e4f1dc8836ded96ca36556b048706
1 /*
2 * sysctl.c: General linux system control interface
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
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/signal.h>
27 #include <linux/printk.h>
28 #include <linux/proc_fs.h>
29 #include <linux/security.h>
30 #include <linux/ctype.h>
31 #include <linux/kmemcheck.h>
32 #include <linux/fs.h>
33 #include <linux/init.h>
34 #include <linux/kernel.h>
35 #include <linux/kobject.h>
36 #include <linux/net.h>
37 #include <linux/sysrq.h>
38 #include <linux/highuid.h>
39 #include <linux/writeback.h>
40 #include <linux/ratelimit.h>
41 #include <linux/compaction.h>
42 #include <linux/hugetlb.h>
43 #include <linux/initrd.h>
44 #include <linux/key.h>
45 #include <linux/times.h>
46 #include <linux/limits.h>
47 #include <linux/dcache.h>
48 #include <linux/dnotify.h>
49 #include <linux/syscalls.h>
50 #include <linux/vmstat.h>
51 #include <linux/nfs_fs.h>
52 #include <linux/acpi.h>
53 #include <linux/reboot.h>
54 #include <linux/ftrace.h>
55 #include <linux/perf_event.h>
56 #include <linux/kprobes.h>
57 #include <linux/pipe_fs_i.h>
58 #include <linux/oom.h>
59 #include <linux/kmod.h>
60 #include <linux/capability.h>
62 #include <asm/uaccess.h>
63 #include <asm/processor.h>
65 #ifdef CONFIG_X86
66 #include <asm/nmi.h>
67 #include <asm/stacktrace.h>
68 #include <asm/io.h>
69 #endif
70 #ifdef CONFIG_BSD_PROCESS_ACCT
71 #include <linux/acct.h>
72 #endif
73 #ifdef CONFIG_RT_MUTEXES
74 #include <linux/rtmutex.h>
75 #endif
76 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
77 #include <linux/lockdep.h>
78 #endif
79 #ifdef CONFIG_CHR_DEV_SG
80 #include <scsi/sg.h>
81 #endif
83 #ifdef CONFIG_LOCKUP_DETECTOR
84 #include <linux/nmi.h>
85 #endif
88 #if defined(CONFIG_SYSCTL)
90 /* External variables not in a header file. */
91 extern int sysctl_overcommit_memory;
92 extern int sysctl_overcommit_ratio;
93 extern int max_threads;
94 extern int core_uses_pid;
95 extern int suid_dumpable;
96 extern char core_pattern[];
97 extern unsigned int core_pipe_limit;
98 extern int pid_max;
99 extern int min_free_kbytes;
100 extern int pid_max_min, pid_max_max;
101 extern int sysctl_drop_caches;
102 extern int percpu_pagelist_fraction;
103 extern int compat_log;
104 extern int latencytop_enabled;
105 extern int sysctl_nr_open_min, sysctl_nr_open_max;
106 #ifndef CONFIG_MMU
107 extern int sysctl_nr_trim_pages;
108 #endif
109 #ifdef CONFIG_BLOCK
110 extern int blk_iopoll_enabled;
111 #endif
113 /* Constants used for minimum and maximum */
114 #ifdef CONFIG_LOCKUP_DETECTOR
115 static int sixty = 60;
116 static int neg_one = -1;
117 #endif
119 static int zero;
120 static int __maybe_unused one = 1;
121 static int __maybe_unused two = 2;
122 static int __maybe_unused three = 3;
123 static unsigned long one_ul = 1;
124 static int one_hundred = 100;
125 #ifdef CONFIG_PRINTK
126 static int ten_thousand = 10000;
127 #endif
129 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
130 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
132 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
133 static int maxolduid = 65535;
134 static int minolduid;
135 static int min_percpu_pagelist_fract = 8;
137 static int ngroups_max = NGROUPS_MAX;
138 static const int cap_last_cap = CAP_LAST_CAP;
140 #ifdef CONFIG_INOTIFY_USER
141 #include <linux/inotify.h>
142 #endif
143 #ifdef CONFIG_SPARC
144 #include <asm/system.h>
145 #endif
147 #ifdef CONFIG_SPARC64
148 extern int sysctl_tsb_ratio;
149 #endif
151 #ifdef __hppa__
152 extern int pwrsw_enabled;
153 extern int unaligned_enabled;
154 #endif
156 #ifdef CONFIG_IA64
157 extern int no_unaligned_warning;
158 extern int unaligned_dump_stack;
159 #endif
161 #ifdef CONFIG_PROC_SYSCTL
162 static int proc_do_cad_pid(struct ctl_table *table, int write,
163 void __user *buffer, size_t *lenp, loff_t *ppos);
164 static int proc_taint(struct ctl_table *table, int write,
165 void __user *buffer, size_t *lenp, loff_t *ppos);
166 #endif
168 #ifdef CONFIG_PRINTK
169 static int proc_dmesg_restrict(struct ctl_table *table, int write,
170 void __user *buffer, size_t *lenp, loff_t *ppos);
171 #endif
173 #ifdef CONFIG_MAGIC_SYSRQ
174 /* Note: sysrq code uses it's own private copy */
175 static int __sysrq_enabled = SYSRQ_DEFAULT_ENABLE;
177 static int sysrq_sysctl_handler(ctl_table *table, int write,
178 void __user *buffer, size_t *lenp,
179 loff_t *ppos)
181 int error;
183 error = proc_dointvec(table, write, buffer, lenp, ppos);
184 if (error)
185 return error;
187 if (write)
188 sysrq_toggle_support(__sysrq_enabled);
190 return 0;
193 #endif
195 static struct ctl_table root_table[];
196 static struct ctl_table_root sysctl_table_root;
197 static struct ctl_table_header root_table_header = {
198 {{.count = 1,
199 .ctl_table = root_table,
200 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),}},
201 .root = &sysctl_table_root,
202 .set = &sysctl_table_root.default_set,
204 static struct ctl_table_root sysctl_table_root = {
205 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
206 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
209 static struct ctl_table kern_table[];
210 static struct ctl_table vm_table[];
211 static struct ctl_table fs_table[];
212 static struct ctl_table debug_table[];
213 static struct ctl_table dev_table[];
214 extern struct ctl_table random_table[];
215 #ifdef CONFIG_EPOLL
216 extern struct ctl_table epoll_table[];
217 #endif
219 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
220 int sysctl_legacy_va_layout;
221 #endif
223 /* The default sysctl tables: */
225 static struct ctl_table root_table[] = {
227 .procname = "kernel",
228 .mode = 0555,
229 .child = kern_table,
232 .procname = "vm",
233 .mode = 0555,
234 .child = vm_table,
237 .procname = "fs",
238 .mode = 0555,
239 .child = fs_table,
242 .procname = "debug",
243 .mode = 0555,
244 .child = debug_table,
247 .procname = "dev",
248 .mode = 0555,
249 .child = dev_table,
254 #ifdef CONFIG_SCHED_DEBUG
255 static int min_sched_granularity_ns = 100000; /* 100 usecs */
256 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
257 static int min_wakeup_granularity_ns; /* 0 usecs */
258 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
259 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
260 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
261 #endif
263 #ifdef CONFIG_COMPACTION
264 static int min_extfrag_threshold;
265 static int max_extfrag_threshold = 1000;
266 #endif
268 static struct ctl_table kern_table[] = {
270 .procname = "sched_child_runs_first",
271 .data = &sysctl_sched_child_runs_first,
272 .maxlen = sizeof(unsigned int),
273 .mode = 0644,
274 .proc_handler = proc_dointvec,
276 #ifdef CONFIG_SCHED_DEBUG
278 .procname = "sched_min_granularity_ns",
279 .data = &sysctl_sched_min_granularity,
280 .maxlen = sizeof(unsigned int),
281 .mode = 0644,
282 .proc_handler = sched_proc_update_handler,
283 .extra1 = &min_sched_granularity_ns,
284 .extra2 = &max_sched_granularity_ns,
287 .procname = "sched_latency_ns",
288 .data = &sysctl_sched_latency,
289 .maxlen = sizeof(unsigned int),
290 .mode = 0644,
291 .proc_handler = sched_proc_update_handler,
292 .extra1 = &min_sched_granularity_ns,
293 .extra2 = &max_sched_granularity_ns,
296 .procname = "sched_wakeup_granularity_ns",
297 .data = &sysctl_sched_wakeup_granularity,
298 .maxlen = sizeof(unsigned int),
299 .mode = 0644,
300 .proc_handler = sched_proc_update_handler,
301 .extra1 = &min_wakeup_granularity_ns,
302 .extra2 = &max_wakeup_granularity_ns,
305 .procname = "sched_tunable_scaling",
306 .data = &sysctl_sched_tunable_scaling,
307 .maxlen = sizeof(enum sched_tunable_scaling),
308 .mode = 0644,
309 .proc_handler = sched_proc_update_handler,
310 .extra1 = &min_sched_tunable_scaling,
311 .extra2 = &max_sched_tunable_scaling,
314 .procname = "sched_migration_cost",
315 .data = &sysctl_sched_migration_cost,
316 .maxlen = sizeof(unsigned int),
317 .mode = 0644,
318 .proc_handler = proc_dointvec,
321 .procname = "sched_nr_migrate",
322 .data = &sysctl_sched_nr_migrate,
323 .maxlen = sizeof(unsigned int),
324 .mode = 0644,
325 .proc_handler = proc_dointvec,
328 .procname = "sched_time_avg",
329 .data = &sysctl_sched_time_avg,
330 .maxlen = sizeof(unsigned int),
331 .mode = 0644,
332 .proc_handler = proc_dointvec,
335 .procname = "sched_shares_window",
336 .data = &sysctl_sched_shares_window,
337 .maxlen = sizeof(unsigned int),
338 .mode = 0644,
339 .proc_handler = proc_dointvec,
342 .procname = "timer_migration",
343 .data = &sysctl_timer_migration,
344 .maxlen = sizeof(unsigned int),
345 .mode = 0644,
346 .proc_handler = proc_dointvec_minmax,
347 .extra1 = &zero,
348 .extra2 = &one,
350 #endif
352 .procname = "sched_rt_period_us",
353 .data = &sysctl_sched_rt_period,
354 .maxlen = sizeof(unsigned int),
355 .mode = 0644,
356 .proc_handler = sched_rt_handler,
359 .procname = "sched_rt_runtime_us",
360 .data = &sysctl_sched_rt_runtime,
361 .maxlen = sizeof(int),
362 .mode = 0644,
363 .proc_handler = sched_rt_handler,
365 #ifdef CONFIG_SCHED_AUTOGROUP
367 .procname = "sched_autogroup_enabled",
368 .data = &sysctl_sched_autogroup_enabled,
369 .maxlen = sizeof(unsigned int),
370 .mode = 0644,
371 .proc_handler = proc_dointvec_minmax,
372 .extra1 = &zero,
373 .extra2 = &one,
375 #endif
376 #ifdef CONFIG_CFS_BANDWIDTH
378 .procname = "sched_cfs_bandwidth_slice_us",
379 .data = &sysctl_sched_cfs_bandwidth_slice,
380 .maxlen = sizeof(unsigned int),
381 .mode = 0644,
382 .proc_handler = proc_dointvec_minmax,
383 .extra1 = &one,
385 #endif
386 #ifdef CONFIG_PROVE_LOCKING
388 .procname = "prove_locking",
389 .data = &prove_locking,
390 .maxlen = sizeof(int),
391 .mode = 0644,
392 .proc_handler = proc_dointvec,
394 #endif
395 #ifdef CONFIG_LOCK_STAT
397 .procname = "lock_stat",
398 .data = &lock_stat,
399 .maxlen = sizeof(int),
400 .mode = 0644,
401 .proc_handler = proc_dointvec,
403 #endif
405 .procname = "panic",
406 .data = &panic_timeout,
407 .maxlen = sizeof(int),
408 .mode = 0644,
409 .proc_handler = proc_dointvec,
412 .procname = "core_uses_pid",
413 .data = &core_uses_pid,
414 .maxlen = sizeof(int),
415 .mode = 0644,
416 .proc_handler = proc_dointvec,
419 .procname = "core_pattern",
420 .data = core_pattern,
421 .maxlen = CORENAME_MAX_SIZE,
422 .mode = 0644,
423 .proc_handler = proc_dostring,
426 .procname = "core_pipe_limit",
427 .data = &core_pipe_limit,
428 .maxlen = sizeof(unsigned int),
429 .mode = 0644,
430 .proc_handler = proc_dointvec,
432 #ifdef CONFIG_PROC_SYSCTL
434 .procname = "tainted",
435 .maxlen = sizeof(long),
436 .mode = 0644,
437 .proc_handler = proc_taint,
439 #endif
440 #ifdef CONFIG_LATENCYTOP
442 .procname = "latencytop",
443 .data = &latencytop_enabled,
444 .maxlen = sizeof(int),
445 .mode = 0644,
446 .proc_handler = proc_dointvec,
448 #endif
449 #ifdef CONFIG_BLK_DEV_INITRD
451 .procname = "real-root-dev",
452 .data = &real_root_dev,
453 .maxlen = sizeof(int),
454 .mode = 0644,
455 .proc_handler = proc_dointvec,
457 #endif
459 .procname = "print-fatal-signals",
460 .data = &print_fatal_signals,
461 .maxlen = sizeof(int),
462 .mode = 0644,
463 .proc_handler = proc_dointvec,
465 #ifdef CONFIG_SPARC
467 .procname = "reboot-cmd",
468 .data = reboot_command,
469 .maxlen = 256,
470 .mode = 0644,
471 .proc_handler = proc_dostring,
474 .procname = "stop-a",
475 .data = &stop_a_enabled,
476 .maxlen = sizeof (int),
477 .mode = 0644,
478 .proc_handler = proc_dointvec,
481 .procname = "scons-poweroff",
482 .data = &scons_pwroff,
483 .maxlen = sizeof (int),
484 .mode = 0644,
485 .proc_handler = proc_dointvec,
487 #endif
488 #ifdef CONFIG_SPARC64
490 .procname = "tsb-ratio",
491 .data = &sysctl_tsb_ratio,
492 .maxlen = sizeof (int),
493 .mode = 0644,
494 .proc_handler = proc_dointvec,
496 #endif
497 #ifdef __hppa__
499 .procname = "soft-power",
500 .data = &pwrsw_enabled,
501 .maxlen = sizeof (int),
502 .mode = 0644,
503 .proc_handler = proc_dointvec,
506 .procname = "unaligned-trap",
507 .data = &unaligned_enabled,
508 .maxlen = sizeof (int),
509 .mode = 0644,
510 .proc_handler = proc_dointvec,
512 #endif
514 .procname = "ctrl-alt-del",
515 .data = &C_A_D,
516 .maxlen = sizeof(int),
517 .mode = 0644,
518 .proc_handler = proc_dointvec,
520 #ifdef CONFIG_FUNCTION_TRACER
522 .procname = "ftrace_enabled",
523 .data = &ftrace_enabled,
524 .maxlen = sizeof(int),
525 .mode = 0644,
526 .proc_handler = ftrace_enable_sysctl,
528 #endif
529 #ifdef CONFIG_STACK_TRACER
531 .procname = "stack_tracer_enabled",
532 .data = &stack_tracer_enabled,
533 .maxlen = sizeof(int),
534 .mode = 0644,
535 .proc_handler = stack_trace_sysctl,
537 #endif
538 #ifdef CONFIG_TRACING
540 .procname = "ftrace_dump_on_oops",
541 .data = &ftrace_dump_on_oops,
542 .maxlen = sizeof(int),
543 .mode = 0644,
544 .proc_handler = proc_dointvec,
546 #endif
547 #ifdef CONFIG_MODULES
549 .procname = "modprobe",
550 .data = &modprobe_path,
551 .maxlen = KMOD_PATH_LEN,
552 .mode = 0644,
553 .proc_handler = proc_dostring,
556 .procname = "modules_disabled",
557 .data = &modules_disabled,
558 .maxlen = sizeof(int),
559 .mode = 0644,
560 /* only handle a transition from default "0" to "1" */
561 .proc_handler = proc_dointvec_minmax,
562 .extra1 = &one,
563 .extra2 = &one,
565 #endif
566 #ifdef CONFIG_HOTPLUG
568 .procname = "hotplug",
569 .data = &uevent_helper,
570 .maxlen = UEVENT_HELPER_PATH_LEN,
571 .mode = 0644,
572 .proc_handler = proc_dostring,
574 #endif
575 #ifdef CONFIG_CHR_DEV_SG
577 .procname = "sg-big-buff",
578 .data = &sg_big_buff,
579 .maxlen = sizeof (int),
580 .mode = 0444,
581 .proc_handler = proc_dointvec,
583 #endif
584 #ifdef CONFIG_BSD_PROCESS_ACCT
586 .procname = "acct",
587 .data = &acct_parm,
588 .maxlen = 3*sizeof(int),
589 .mode = 0644,
590 .proc_handler = proc_dointvec,
592 #endif
593 #ifdef CONFIG_MAGIC_SYSRQ
595 .procname = "sysrq",
596 .data = &__sysrq_enabled,
597 .maxlen = sizeof (int),
598 .mode = 0644,
599 .proc_handler = sysrq_sysctl_handler,
601 #endif
602 #ifdef CONFIG_PROC_SYSCTL
604 .procname = "cad_pid",
605 .data = NULL,
606 .maxlen = sizeof (int),
607 .mode = 0600,
608 .proc_handler = proc_do_cad_pid,
610 #endif
612 .procname = "threads-max",
613 .data = &max_threads,
614 .maxlen = sizeof(int),
615 .mode = 0644,
616 .proc_handler = proc_dointvec,
619 .procname = "random",
620 .mode = 0555,
621 .child = random_table,
624 .procname = "usermodehelper",
625 .mode = 0555,
626 .child = usermodehelper_table,
629 .procname = "overflowuid",
630 .data = &overflowuid,
631 .maxlen = sizeof(int),
632 .mode = 0644,
633 .proc_handler = proc_dointvec_minmax,
634 .extra1 = &minolduid,
635 .extra2 = &maxolduid,
638 .procname = "overflowgid",
639 .data = &overflowgid,
640 .maxlen = sizeof(int),
641 .mode = 0644,
642 .proc_handler = proc_dointvec_minmax,
643 .extra1 = &minolduid,
644 .extra2 = &maxolduid,
646 #ifdef CONFIG_S390
647 #ifdef CONFIG_MATHEMU
649 .procname = "ieee_emulation_warnings",
650 .data = &sysctl_ieee_emulation_warnings,
651 .maxlen = sizeof(int),
652 .mode = 0644,
653 .proc_handler = proc_dointvec,
655 #endif
657 .procname = "userprocess_debug",
658 .data = &show_unhandled_signals,
659 .maxlen = sizeof(int),
660 .mode = 0644,
661 .proc_handler = proc_dointvec,
663 #endif
665 .procname = "pid_max",
666 .data = &pid_max,
667 .maxlen = sizeof (int),
668 .mode = 0644,
669 .proc_handler = proc_dointvec_minmax,
670 .extra1 = &pid_max_min,
671 .extra2 = &pid_max_max,
674 .procname = "panic_on_oops",
675 .data = &panic_on_oops,
676 .maxlen = sizeof(int),
677 .mode = 0644,
678 .proc_handler = proc_dointvec,
680 #if defined CONFIG_PRINTK
682 .procname = "printk",
683 .data = &console_loglevel,
684 .maxlen = 4*sizeof(int),
685 .mode = 0644,
686 .proc_handler = proc_dointvec,
689 .procname = "printk_ratelimit",
690 .data = &printk_ratelimit_state.interval,
691 .maxlen = sizeof(int),
692 .mode = 0644,
693 .proc_handler = proc_dointvec_jiffies,
696 .procname = "printk_ratelimit_burst",
697 .data = &printk_ratelimit_state.burst,
698 .maxlen = sizeof(int),
699 .mode = 0644,
700 .proc_handler = proc_dointvec,
703 .procname = "printk_delay",
704 .data = &printk_delay_msec,
705 .maxlen = sizeof(int),
706 .mode = 0644,
707 .proc_handler = proc_dointvec_minmax,
708 .extra1 = &zero,
709 .extra2 = &ten_thousand,
712 .procname = "dmesg_restrict",
713 .data = &dmesg_restrict,
714 .maxlen = sizeof(int),
715 .mode = 0644,
716 .proc_handler = proc_dointvec_minmax,
717 .extra1 = &zero,
718 .extra2 = &one,
721 .procname = "kptr_restrict",
722 .data = &kptr_restrict,
723 .maxlen = sizeof(int),
724 .mode = 0644,
725 .proc_handler = proc_dmesg_restrict,
726 .extra1 = &zero,
727 .extra2 = &two,
729 #endif
731 .procname = "ngroups_max",
732 .data = &ngroups_max,
733 .maxlen = sizeof (int),
734 .mode = 0444,
735 .proc_handler = proc_dointvec,
738 .procname = "cap_last_cap",
739 .data = (void *)&cap_last_cap,
740 .maxlen = sizeof(int),
741 .mode = 0444,
742 .proc_handler = proc_dointvec,
744 #if defined(CONFIG_LOCKUP_DETECTOR)
746 .procname = "watchdog",
747 .data = &watchdog_enabled,
748 .maxlen = sizeof (int),
749 .mode = 0644,
750 .proc_handler = proc_dowatchdog,
751 .extra1 = &zero,
752 .extra2 = &one,
755 .procname = "watchdog_thresh",
756 .data = &watchdog_thresh,
757 .maxlen = sizeof(int),
758 .mode = 0644,
759 .proc_handler = proc_dowatchdog,
760 .extra1 = &neg_one,
761 .extra2 = &sixty,
764 .procname = "softlockup_panic",
765 .data = &softlockup_panic,
766 .maxlen = sizeof(int),
767 .mode = 0644,
768 .proc_handler = proc_dointvec_minmax,
769 .extra1 = &zero,
770 .extra2 = &one,
773 .procname = "nmi_watchdog",
774 .data = &watchdog_enabled,
775 .maxlen = sizeof (int),
776 .mode = 0644,
777 .proc_handler = proc_dowatchdog,
778 .extra1 = &zero,
779 .extra2 = &one,
781 #endif
782 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
784 .procname = "unknown_nmi_panic",
785 .data = &unknown_nmi_panic,
786 .maxlen = sizeof (int),
787 .mode = 0644,
788 .proc_handler = proc_dointvec,
790 #endif
791 #if defined(CONFIG_X86)
793 .procname = "panic_on_unrecovered_nmi",
794 .data = &panic_on_unrecovered_nmi,
795 .maxlen = sizeof(int),
796 .mode = 0644,
797 .proc_handler = proc_dointvec,
800 .procname = "panic_on_io_nmi",
801 .data = &panic_on_io_nmi,
802 .maxlen = sizeof(int),
803 .mode = 0644,
804 .proc_handler = proc_dointvec,
806 #ifdef CONFIG_DEBUG_STACKOVERFLOW
808 .procname = "panic_on_stackoverflow",
809 .data = &sysctl_panic_on_stackoverflow,
810 .maxlen = sizeof(int),
811 .mode = 0644,
812 .proc_handler = proc_dointvec,
814 #endif
816 .procname = "bootloader_type",
817 .data = &bootloader_type,
818 .maxlen = sizeof (int),
819 .mode = 0444,
820 .proc_handler = proc_dointvec,
823 .procname = "bootloader_version",
824 .data = &bootloader_version,
825 .maxlen = sizeof (int),
826 .mode = 0444,
827 .proc_handler = proc_dointvec,
830 .procname = "kstack_depth_to_print",
831 .data = &kstack_depth_to_print,
832 .maxlen = sizeof(int),
833 .mode = 0644,
834 .proc_handler = proc_dointvec,
837 .procname = "io_delay_type",
838 .data = &io_delay_type,
839 .maxlen = sizeof(int),
840 .mode = 0644,
841 .proc_handler = proc_dointvec,
843 #endif
844 #if defined(CONFIG_MMU)
846 .procname = "randomize_va_space",
847 .data = &randomize_va_space,
848 .maxlen = sizeof(int),
849 .mode = 0644,
850 .proc_handler = proc_dointvec,
852 #endif
853 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
855 .procname = "spin_retry",
856 .data = &spin_retry,
857 .maxlen = sizeof (int),
858 .mode = 0644,
859 .proc_handler = proc_dointvec,
861 #endif
862 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
864 .procname = "acpi_video_flags",
865 .data = &acpi_realmode_flags,
866 .maxlen = sizeof (unsigned long),
867 .mode = 0644,
868 .proc_handler = proc_doulongvec_minmax,
870 #endif
871 #ifdef CONFIG_IA64
873 .procname = "ignore-unaligned-usertrap",
874 .data = &no_unaligned_warning,
875 .maxlen = sizeof (int),
876 .mode = 0644,
877 .proc_handler = proc_dointvec,
880 .procname = "unaligned-dump-stack",
881 .data = &unaligned_dump_stack,
882 .maxlen = sizeof (int),
883 .mode = 0644,
884 .proc_handler = proc_dointvec,
886 #endif
887 #ifdef CONFIG_DETECT_HUNG_TASK
889 .procname = "hung_task_panic",
890 .data = &sysctl_hung_task_panic,
891 .maxlen = sizeof(int),
892 .mode = 0644,
893 .proc_handler = proc_dointvec_minmax,
894 .extra1 = &zero,
895 .extra2 = &one,
898 .procname = "hung_task_check_count",
899 .data = &sysctl_hung_task_check_count,
900 .maxlen = sizeof(unsigned long),
901 .mode = 0644,
902 .proc_handler = proc_doulongvec_minmax,
905 .procname = "hung_task_timeout_secs",
906 .data = &sysctl_hung_task_timeout_secs,
907 .maxlen = sizeof(unsigned long),
908 .mode = 0644,
909 .proc_handler = proc_dohung_task_timeout_secs,
912 .procname = "hung_task_warnings",
913 .data = &sysctl_hung_task_warnings,
914 .maxlen = sizeof(unsigned long),
915 .mode = 0644,
916 .proc_handler = proc_doulongvec_minmax,
918 #endif
919 #ifdef CONFIG_COMPAT
921 .procname = "compat-log",
922 .data = &compat_log,
923 .maxlen = sizeof (int),
924 .mode = 0644,
925 .proc_handler = proc_dointvec,
927 #endif
928 #ifdef CONFIG_RT_MUTEXES
930 .procname = "max_lock_depth",
931 .data = &max_lock_depth,
932 .maxlen = sizeof(int),
933 .mode = 0644,
934 .proc_handler = proc_dointvec,
936 #endif
938 .procname = "poweroff_cmd",
939 .data = &poweroff_cmd,
940 .maxlen = POWEROFF_CMD_PATH_LEN,
941 .mode = 0644,
942 .proc_handler = proc_dostring,
944 #ifdef CONFIG_KEYS
946 .procname = "keys",
947 .mode = 0555,
948 .child = key_sysctls,
950 #endif
951 #ifdef CONFIG_RCU_TORTURE_TEST
953 .procname = "rcutorture_runnable",
954 .data = &rcutorture_runnable,
955 .maxlen = sizeof(int),
956 .mode = 0644,
957 .proc_handler = proc_dointvec,
959 #endif
960 #ifdef CONFIG_PERF_EVENTS
962 * User-space scripts rely on the existence of this file
963 * as a feature check for perf_events being enabled.
965 * So it's an ABI, do not remove!
968 .procname = "perf_event_paranoid",
969 .data = &sysctl_perf_event_paranoid,
970 .maxlen = sizeof(sysctl_perf_event_paranoid),
971 .mode = 0644,
972 .proc_handler = proc_dointvec,
975 .procname = "perf_event_mlock_kb",
976 .data = &sysctl_perf_event_mlock,
977 .maxlen = sizeof(sysctl_perf_event_mlock),
978 .mode = 0644,
979 .proc_handler = proc_dointvec,
982 .procname = "perf_event_max_sample_rate",
983 .data = &sysctl_perf_event_sample_rate,
984 .maxlen = sizeof(sysctl_perf_event_sample_rate),
985 .mode = 0644,
986 .proc_handler = perf_proc_update_handler,
988 #endif
989 #ifdef CONFIG_KMEMCHECK
991 .procname = "kmemcheck",
992 .data = &kmemcheck_enabled,
993 .maxlen = sizeof(int),
994 .mode = 0644,
995 .proc_handler = proc_dointvec,
997 #endif
998 #ifdef CONFIG_BLOCK
1000 .procname = "blk_iopoll",
1001 .data = &blk_iopoll_enabled,
1002 .maxlen = sizeof(int),
1003 .mode = 0644,
1004 .proc_handler = proc_dointvec,
1006 #endif
1010 static struct ctl_table vm_table[] = {
1012 .procname = "overcommit_memory",
1013 .data = &sysctl_overcommit_memory,
1014 .maxlen = sizeof(sysctl_overcommit_memory),
1015 .mode = 0644,
1016 .proc_handler = proc_dointvec_minmax,
1017 .extra1 = &zero,
1018 .extra2 = &two,
1021 .procname = "panic_on_oom",
1022 .data = &sysctl_panic_on_oom,
1023 .maxlen = sizeof(sysctl_panic_on_oom),
1024 .mode = 0644,
1025 .proc_handler = proc_dointvec_minmax,
1026 .extra1 = &zero,
1027 .extra2 = &two,
1030 .procname = "oom_kill_allocating_task",
1031 .data = &sysctl_oom_kill_allocating_task,
1032 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1033 .mode = 0644,
1034 .proc_handler = proc_dointvec,
1037 .procname = "oom_dump_tasks",
1038 .data = &sysctl_oom_dump_tasks,
1039 .maxlen = sizeof(sysctl_oom_dump_tasks),
1040 .mode = 0644,
1041 .proc_handler = proc_dointvec,
1044 .procname = "overcommit_ratio",
1045 .data = &sysctl_overcommit_ratio,
1046 .maxlen = sizeof(sysctl_overcommit_ratio),
1047 .mode = 0644,
1048 .proc_handler = proc_dointvec,
1051 .procname = "page-cluster",
1052 .data = &page_cluster,
1053 .maxlen = sizeof(int),
1054 .mode = 0644,
1055 .proc_handler = proc_dointvec_minmax,
1056 .extra1 = &zero,
1059 .procname = "dirty_background_ratio",
1060 .data = &dirty_background_ratio,
1061 .maxlen = sizeof(dirty_background_ratio),
1062 .mode = 0644,
1063 .proc_handler = dirty_background_ratio_handler,
1064 .extra1 = &zero,
1065 .extra2 = &one_hundred,
1068 .procname = "dirty_background_bytes",
1069 .data = &dirty_background_bytes,
1070 .maxlen = sizeof(dirty_background_bytes),
1071 .mode = 0644,
1072 .proc_handler = dirty_background_bytes_handler,
1073 .extra1 = &one_ul,
1076 .procname = "dirty_ratio",
1077 .data = &vm_dirty_ratio,
1078 .maxlen = sizeof(vm_dirty_ratio),
1079 .mode = 0644,
1080 .proc_handler = dirty_ratio_handler,
1081 .extra1 = &zero,
1082 .extra2 = &one_hundred,
1085 .procname = "dirty_bytes",
1086 .data = &vm_dirty_bytes,
1087 .maxlen = sizeof(vm_dirty_bytes),
1088 .mode = 0644,
1089 .proc_handler = dirty_bytes_handler,
1090 .extra1 = &dirty_bytes_min,
1093 .procname = "dirty_writeback_centisecs",
1094 .data = &dirty_writeback_interval,
1095 .maxlen = sizeof(dirty_writeback_interval),
1096 .mode = 0644,
1097 .proc_handler = dirty_writeback_centisecs_handler,
1100 .procname = "dirty_expire_centisecs",
1101 .data = &dirty_expire_interval,
1102 .maxlen = sizeof(dirty_expire_interval),
1103 .mode = 0644,
1104 .proc_handler = proc_dointvec_minmax,
1105 .extra1 = &zero,
1108 .procname = "nr_pdflush_threads",
1109 .data = &nr_pdflush_threads,
1110 .maxlen = sizeof nr_pdflush_threads,
1111 .mode = 0444 /* read-only*/,
1112 .proc_handler = proc_dointvec,
1115 .procname = "swappiness",
1116 .data = &vm_swappiness,
1117 .maxlen = sizeof(vm_swappiness),
1118 .mode = 0644,
1119 .proc_handler = proc_dointvec_minmax,
1120 .extra1 = &zero,
1121 .extra2 = &one_hundred,
1123 #ifdef CONFIG_HUGETLB_PAGE
1125 .procname = "nr_hugepages",
1126 .data = NULL,
1127 .maxlen = sizeof(unsigned long),
1128 .mode = 0644,
1129 .proc_handler = hugetlb_sysctl_handler,
1130 .extra1 = (void *)&hugetlb_zero,
1131 .extra2 = (void *)&hugetlb_infinity,
1133 #ifdef CONFIG_NUMA
1135 .procname = "nr_hugepages_mempolicy",
1136 .data = NULL,
1137 .maxlen = sizeof(unsigned long),
1138 .mode = 0644,
1139 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1140 .extra1 = (void *)&hugetlb_zero,
1141 .extra2 = (void *)&hugetlb_infinity,
1143 #endif
1145 .procname = "hugetlb_shm_group",
1146 .data = &sysctl_hugetlb_shm_group,
1147 .maxlen = sizeof(gid_t),
1148 .mode = 0644,
1149 .proc_handler = proc_dointvec,
1152 .procname = "hugepages_treat_as_movable",
1153 .data = &hugepages_treat_as_movable,
1154 .maxlen = sizeof(int),
1155 .mode = 0644,
1156 .proc_handler = hugetlb_treat_movable_handler,
1159 .procname = "nr_overcommit_hugepages",
1160 .data = NULL,
1161 .maxlen = sizeof(unsigned long),
1162 .mode = 0644,
1163 .proc_handler = hugetlb_overcommit_handler,
1164 .extra1 = (void *)&hugetlb_zero,
1165 .extra2 = (void *)&hugetlb_infinity,
1167 #endif
1169 .procname = "lowmem_reserve_ratio",
1170 .data = &sysctl_lowmem_reserve_ratio,
1171 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1172 .mode = 0644,
1173 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1176 .procname = "drop_caches",
1177 .data = &sysctl_drop_caches,
1178 .maxlen = sizeof(int),
1179 .mode = 0644,
1180 .proc_handler = drop_caches_sysctl_handler,
1181 .extra1 = &one,
1182 .extra2 = &three,
1184 #ifdef CONFIG_COMPACTION
1186 .procname = "compact_memory",
1187 .data = &sysctl_compact_memory,
1188 .maxlen = sizeof(int),
1189 .mode = 0200,
1190 .proc_handler = sysctl_compaction_handler,
1193 .procname = "extfrag_threshold",
1194 .data = &sysctl_extfrag_threshold,
1195 .maxlen = sizeof(int),
1196 .mode = 0644,
1197 .proc_handler = sysctl_extfrag_handler,
1198 .extra1 = &min_extfrag_threshold,
1199 .extra2 = &max_extfrag_threshold,
1202 #endif /* CONFIG_COMPACTION */
1204 .procname = "min_free_kbytes",
1205 .data = &min_free_kbytes,
1206 .maxlen = sizeof(min_free_kbytes),
1207 .mode = 0644,
1208 .proc_handler = min_free_kbytes_sysctl_handler,
1209 .extra1 = &zero,
1212 .procname = "percpu_pagelist_fraction",
1213 .data = &percpu_pagelist_fraction,
1214 .maxlen = sizeof(percpu_pagelist_fraction),
1215 .mode = 0644,
1216 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1217 .extra1 = &min_percpu_pagelist_fract,
1219 #ifdef CONFIG_MMU
1221 .procname = "max_map_count",
1222 .data = &sysctl_max_map_count,
1223 .maxlen = sizeof(sysctl_max_map_count),
1224 .mode = 0644,
1225 .proc_handler = proc_dointvec_minmax,
1226 .extra1 = &zero,
1228 #else
1230 .procname = "nr_trim_pages",
1231 .data = &sysctl_nr_trim_pages,
1232 .maxlen = sizeof(sysctl_nr_trim_pages),
1233 .mode = 0644,
1234 .proc_handler = proc_dointvec_minmax,
1235 .extra1 = &zero,
1237 #endif
1239 .procname = "laptop_mode",
1240 .data = &laptop_mode,
1241 .maxlen = sizeof(laptop_mode),
1242 .mode = 0644,
1243 .proc_handler = proc_dointvec_jiffies,
1246 .procname = "block_dump",
1247 .data = &block_dump,
1248 .maxlen = sizeof(block_dump),
1249 .mode = 0644,
1250 .proc_handler = proc_dointvec,
1251 .extra1 = &zero,
1254 .procname = "vfs_cache_pressure",
1255 .data = &sysctl_vfs_cache_pressure,
1256 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1257 .mode = 0644,
1258 .proc_handler = proc_dointvec,
1259 .extra1 = &zero,
1261 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1263 .procname = "legacy_va_layout",
1264 .data = &sysctl_legacy_va_layout,
1265 .maxlen = sizeof(sysctl_legacy_va_layout),
1266 .mode = 0644,
1267 .proc_handler = proc_dointvec,
1268 .extra1 = &zero,
1270 #endif
1271 #ifdef CONFIG_NUMA
1273 .procname = "zone_reclaim_mode",
1274 .data = &zone_reclaim_mode,
1275 .maxlen = sizeof(zone_reclaim_mode),
1276 .mode = 0644,
1277 .proc_handler = proc_dointvec,
1278 .extra1 = &zero,
1281 .procname = "min_unmapped_ratio",
1282 .data = &sysctl_min_unmapped_ratio,
1283 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1284 .mode = 0644,
1285 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1286 .extra1 = &zero,
1287 .extra2 = &one_hundred,
1290 .procname = "min_slab_ratio",
1291 .data = &sysctl_min_slab_ratio,
1292 .maxlen = sizeof(sysctl_min_slab_ratio),
1293 .mode = 0644,
1294 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1295 .extra1 = &zero,
1296 .extra2 = &one_hundred,
1298 #endif
1299 #ifdef CONFIG_SMP
1301 .procname = "stat_interval",
1302 .data = &sysctl_stat_interval,
1303 .maxlen = sizeof(sysctl_stat_interval),
1304 .mode = 0644,
1305 .proc_handler = proc_dointvec_jiffies,
1307 #endif
1308 #ifdef CONFIG_MMU
1310 .procname = "mmap_min_addr",
1311 .data = &dac_mmap_min_addr,
1312 .maxlen = sizeof(unsigned long),
1313 .mode = 0644,
1314 .proc_handler = mmap_min_addr_handler,
1316 #endif
1317 #ifdef CONFIG_NUMA
1319 .procname = "numa_zonelist_order",
1320 .data = &numa_zonelist_order,
1321 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1322 .mode = 0644,
1323 .proc_handler = numa_zonelist_order_handler,
1325 #endif
1326 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1327 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1329 .procname = "vdso_enabled",
1330 .data = &vdso_enabled,
1331 .maxlen = sizeof(vdso_enabled),
1332 .mode = 0644,
1333 .proc_handler = proc_dointvec,
1334 .extra1 = &zero,
1336 #endif
1337 #ifdef CONFIG_HIGHMEM
1339 .procname = "highmem_is_dirtyable",
1340 .data = &vm_highmem_is_dirtyable,
1341 .maxlen = sizeof(vm_highmem_is_dirtyable),
1342 .mode = 0644,
1343 .proc_handler = proc_dointvec_minmax,
1344 .extra1 = &zero,
1345 .extra2 = &one,
1347 #endif
1349 .procname = "scan_unevictable_pages",
1350 .data = &scan_unevictable_pages,
1351 .maxlen = sizeof(scan_unevictable_pages),
1352 .mode = 0644,
1353 .proc_handler = scan_unevictable_handler,
1355 #ifdef CONFIG_MEMORY_FAILURE
1357 .procname = "memory_failure_early_kill",
1358 .data = &sysctl_memory_failure_early_kill,
1359 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1360 .mode = 0644,
1361 .proc_handler = proc_dointvec_minmax,
1362 .extra1 = &zero,
1363 .extra2 = &one,
1366 .procname = "memory_failure_recovery",
1367 .data = &sysctl_memory_failure_recovery,
1368 .maxlen = sizeof(sysctl_memory_failure_recovery),
1369 .mode = 0644,
1370 .proc_handler = proc_dointvec_minmax,
1371 .extra1 = &zero,
1372 .extra2 = &one,
1374 #endif
1378 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1379 static struct ctl_table binfmt_misc_table[] = {
1382 #endif
1384 static struct ctl_table fs_table[] = {
1386 .procname = "inode-nr",
1387 .data = &inodes_stat,
1388 .maxlen = 2*sizeof(int),
1389 .mode = 0444,
1390 .proc_handler = proc_nr_inodes,
1393 .procname = "inode-state",
1394 .data = &inodes_stat,
1395 .maxlen = 7*sizeof(int),
1396 .mode = 0444,
1397 .proc_handler = proc_nr_inodes,
1400 .procname = "file-nr",
1401 .data = &files_stat,
1402 .maxlen = sizeof(files_stat),
1403 .mode = 0444,
1404 .proc_handler = proc_nr_files,
1407 .procname = "file-max",
1408 .data = &files_stat.max_files,
1409 .maxlen = sizeof(files_stat.max_files),
1410 .mode = 0644,
1411 .proc_handler = proc_doulongvec_minmax,
1414 .procname = "nr_open",
1415 .data = &sysctl_nr_open,
1416 .maxlen = sizeof(int),
1417 .mode = 0644,
1418 .proc_handler = proc_dointvec_minmax,
1419 .extra1 = &sysctl_nr_open_min,
1420 .extra2 = &sysctl_nr_open_max,
1423 .procname = "dentry-state",
1424 .data = &dentry_stat,
1425 .maxlen = 6*sizeof(int),
1426 .mode = 0444,
1427 .proc_handler = proc_nr_dentry,
1430 .procname = "overflowuid",
1431 .data = &fs_overflowuid,
1432 .maxlen = sizeof(int),
1433 .mode = 0644,
1434 .proc_handler = proc_dointvec_minmax,
1435 .extra1 = &minolduid,
1436 .extra2 = &maxolduid,
1439 .procname = "overflowgid",
1440 .data = &fs_overflowgid,
1441 .maxlen = sizeof(int),
1442 .mode = 0644,
1443 .proc_handler = proc_dointvec_minmax,
1444 .extra1 = &minolduid,
1445 .extra2 = &maxolduid,
1447 #ifdef CONFIG_FILE_LOCKING
1449 .procname = "leases-enable",
1450 .data = &leases_enable,
1451 .maxlen = sizeof(int),
1452 .mode = 0644,
1453 .proc_handler = proc_dointvec,
1455 #endif
1456 #ifdef CONFIG_DNOTIFY
1458 .procname = "dir-notify-enable",
1459 .data = &dir_notify_enable,
1460 .maxlen = sizeof(int),
1461 .mode = 0644,
1462 .proc_handler = proc_dointvec,
1464 #endif
1465 #ifdef CONFIG_MMU
1466 #ifdef CONFIG_FILE_LOCKING
1468 .procname = "lease-break-time",
1469 .data = &lease_break_time,
1470 .maxlen = sizeof(int),
1471 .mode = 0644,
1472 .proc_handler = proc_dointvec,
1474 #endif
1475 #ifdef CONFIG_AIO
1477 .procname = "aio-nr",
1478 .data = &aio_nr,
1479 .maxlen = sizeof(aio_nr),
1480 .mode = 0444,
1481 .proc_handler = proc_doulongvec_minmax,
1484 .procname = "aio-max-nr",
1485 .data = &aio_max_nr,
1486 .maxlen = sizeof(aio_max_nr),
1487 .mode = 0644,
1488 .proc_handler = proc_doulongvec_minmax,
1490 #endif /* CONFIG_AIO */
1491 #ifdef CONFIG_INOTIFY_USER
1493 .procname = "inotify",
1494 .mode = 0555,
1495 .child = inotify_table,
1497 #endif
1498 #ifdef CONFIG_EPOLL
1500 .procname = "epoll",
1501 .mode = 0555,
1502 .child = epoll_table,
1504 #endif
1505 #endif
1507 .procname = "suid_dumpable",
1508 .data = &suid_dumpable,
1509 .maxlen = sizeof(int),
1510 .mode = 0644,
1511 .proc_handler = proc_dointvec_minmax,
1512 .extra1 = &zero,
1513 .extra2 = &two,
1515 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1517 .procname = "binfmt_misc",
1518 .mode = 0555,
1519 .child = binfmt_misc_table,
1521 #endif
1523 .procname = "pipe-max-size",
1524 .data = &pipe_max_size,
1525 .maxlen = sizeof(int),
1526 .mode = 0644,
1527 .proc_handler = &pipe_proc_fn,
1528 .extra1 = &pipe_min_size,
1533 static struct ctl_table debug_table[] = {
1534 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
1535 defined(CONFIG_S390) || defined(CONFIG_TILE)
1537 .procname = "exception-trace",
1538 .data = &show_unhandled_signals,
1539 .maxlen = sizeof(int),
1540 .mode = 0644,
1541 .proc_handler = proc_dointvec
1543 #endif
1544 #if defined(CONFIG_OPTPROBES)
1546 .procname = "kprobes-optimization",
1547 .data = &sysctl_kprobes_optimization,
1548 .maxlen = sizeof(int),
1549 .mode = 0644,
1550 .proc_handler = proc_kprobes_optimization_handler,
1551 .extra1 = &zero,
1552 .extra2 = &one,
1554 #endif
1558 static struct ctl_table dev_table[] = {
1562 static DEFINE_SPINLOCK(sysctl_lock);
1564 /* called under sysctl_lock */
1565 static int use_table(struct ctl_table_header *p)
1567 if (unlikely(p->unregistering))
1568 return 0;
1569 p->used++;
1570 return 1;
1573 /* called under sysctl_lock */
1574 static void unuse_table(struct ctl_table_header *p)
1576 if (!--p->used)
1577 if (unlikely(p->unregistering))
1578 complete(p->unregistering);
1581 /* called under sysctl_lock, will reacquire if has to wait */
1582 static void start_unregistering(struct ctl_table_header *p)
1585 * if p->used is 0, nobody will ever touch that entry again;
1586 * we'll eliminate all paths to it before dropping sysctl_lock
1588 if (unlikely(p->used)) {
1589 struct completion wait;
1590 init_completion(&wait);
1591 p->unregistering = &wait;
1592 spin_unlock(&sysctl_lock);
1593 wait_for_completion(&wait);
1594 spin_lock(&sysctl_lock);
1595 } else {
1596 /* anything non-NULL; we'll never dereference it */
1597 p->unregistering = ERR_PTR(-EINVAL);
1600 * do not remove from the list until nobody holds it; walking the
1601 * list in do_sysctl() relies on that.
1603 list_del_init(&p->ctl_entry);
1606 void sysctl_head_get(struct ctl_table_header *head)
1608 spin_lock(&sysctl_lock);
1609 head->count++;
1610 spin_unlock(&sysctl_lock);
1613 void sysctl_head_put(struct ctl_table_header *head)
1615 spin_lock(&sysctl_lock);
1616 if (!--head->count)
1617 kfree_rcu(head, rcu);
1618 spin_unlock(&sysctl_lock);
1621 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1623 if (!head)
1624 BUG();
1625 spin_lock(&sysctl_lock);
1626 if (!use_table(head))
1627 head = ERR_PTR(-ENOENT);
1628 spin_unlock(&sysctl_lock);
1629 return head;
1632 void sysctl_head_finish(struct ctl_table_header *head)
1634 if (!head)
1635 return;
1636 spin_lock(&sysctl_lock);
1637 unuse_table(head);
1638 spin_unlock(&sysctl_lock);
1641 static struct ctl_table_set *
1642 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1644 struct ctl_table_set *set = &root->default_set;
1645 if (root->lookup)
1646 set = root->lookup(root, namespaces);
1647 return set;
1650 static struct list_head *
1651 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1653 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1654 return &set->list;
1657 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1658 struct ctl_table_header *prev)
1660 struct ctl_table_root *root;
1661 struct list_head *header_list;
1662 struct ctl_table_header *head;
1663 struct list_head *tmp;
1665 spin_lock(&sysctl_lock);
1666 if (prev) {
1667 head = prev;
1668 tmp = &prev->ctl_entry;
1669 unuse_table(prev);
1670 goto next;
1672 tmp = &root_table_header.ctl_entry;
1673 for (;;) {
1674 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1676 if (!use_table(head))
1677 goto next;
1678 spin_unlock(&sysctl_lock);
1679 return head;
1680 next:
1681 root = head->root;
1682 tmp = tmp->next;
1683 header_list = lookup_header_list(root, namespaces);
1684 if (tmp != header_list)
1685 continue;
1687 do {
1688 root = list_entry(root->root_list.next,
1689 struct ctl_table_root, root_list);
1690 if (root == &sysctl_table_root)
1691 goto out;
1692 header_list = lookup_header_list(root, namespaces);
1693 } while (list_empty(header_list));
1694 tmp = header_list->next;
1696 out:
1697 spin_unlock(&sysctl_lock);
1698 return NULL;
1701 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1703 return __sysctl_head_next(current->nsproxy, prev);
1706 void register_sysctl_root(struct ctl_table_root *root)
1708 spin_lock(&sysctl_lock);
1709 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1710 spin_unlock(&sysctl_lock);
1714 * sysctl_perm does NOT grant the superuser all rights automatically, because
1715 * some sysctl variables are readonly even to root.
1718 static int test_perm(int mode, int op)
1720 if (!current_euid())
1721 mode >>= 6;
1722 else if (in_egroup_p(0))
1723 mode >>= 3;
1724 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1725 return 0;
1726 return -EACCES;
1729 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1731 int mode;
1733 if (root->permissions)
1734 mode = root->permissions(root, current->nsproxy, table);
1735 else
1736 mode = table->mode;
1738 return test_perm(mode, op);
1741 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1743 for (; table->procname; table++) {
1744 table->parent = parent;
1745 if (table->child)
1746 sysctl_set_parent(table, table->child);
1750 static __init int sysctl_init(void)
1752 sysctl_set_parent(NULL, root_table);
1753 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1754 sysctl_check_table(current->nsproxy, root_table);
1755 #endif
1756 return 0;
1759 core_initcall(sysctl_init);
1761 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1762 struct ctl_table *table)
1764 struct ctl_table *p;
1765 const char *s = branch->procname;
1767 /* branch should have named subdirectory as its first element */
1768 if (!s || !branch->child)
1769 return NULL;
1771 /* ... and nothing else */
1772 if (branch[1].procname)
1773 return NULL;
1775 /* table should contain subdirectory with the same name */
1776 for (p = table; p->procname; p++) {
1777 if (!p->child)
1778 continue;
1779 if (p->procname && strcmp(p->procname, s) == 0)
1780 return p;
1782 return NULL;
1785 /* see if attaching q to p would be an improvement */
1786 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1788 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1789 struct ctl_table *next;
1790 int is_better = 0;
1791 int not_in_parent = !p->attached_by;
1793 while ((next = is_branch_in(by, to)) != NULL) {
1794 if (by == q->attached_by)
1795 is_better = 1;
1796 if (to == p->attached_by)
1797 not_in_parent = 1;
1798 by = by->child;
1799 to = next->child;
1802 if (is_better && not_in_parent) {
1803 q->attached_by = by;
1804 q->attached_to = to;
1805 q->parent = p;
1810 * __register_sysctl_paths - register a sysctl hierarchy
1811 * @root: List of sysctl headers to register on
1812 * @namespaces: Data to compute which lists of sysctl entries are visible
1813 * @path: The path to the directory the sysctl table is in.
1814 * @table: the top-level table structure
1816 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1817 * array. A completely 0 filled entry terminates the table.
1819 * The members of the &struct ctl_table structure are used as follows:
1821 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1822 * enter a sysctl file
1824 * data - a pointer to data for use by proc_handler
1826 * maxlen - the maximum size in bytes of the data
1828 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1830 * child - a pointer to the child sysctl table if this entry is a directory, or
1831 * %NULL.
1833 * proc_handler - the text handler routine (described below)
1835 * de - for internal use by the sysctl routines
1837 * extra1, extra2 - extra pointers usable by the proc handler routines
1839 * Leaf nodes in the sysctl tree will be represented by a single file
1840 * under /proc; non-leaf nodes will be represented by directories.
1842 * sysctl(2) can automatically manage read and write requests through
1843 * the sysctl table. The data and maxlen fields of the ctl_table
1844 * struct enable minimal validation of the values being written to be
1845 * performed, and the mode field allows minimal authentication.
1847 * There must be a proc_handler routine for any terminal nodes
1848 * mirrored under /proc/sys (non-terminals are handled by a built-in
1849 * directory handler). Several default handlers are available to
1850 * cover common cases -
1852 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1853 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1854 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1856 * It is the handler's job to read the input buffer from user memory
1857 * and process it. The handler should return 0 on success.
1859 * This routine returns %NULL on a failure to register, and a pointer
1860 * to the table header on success.
1862 struct ctl_table_header *__register_sysctl_paths(
1863 struct ctl_table_root *root,
1864 struct nsproxy *namespaces,
1865 const struct ctl_path *path, struct ctl_table *table)
1867 struct ctl_table_header *header;
1868 struct ctl_table *new, **prevp;
1869 unsigned int n, npath;
1870 struct ctl_table_set *set;
1872 /* Count the path components */
1873 for (npath = 0; path[npath].procname; ++npath)
1877 * For each path component, allocate a 2-element ctl_table array.
1878 * The first array element will be filled with the sysctl entry
1879 * for this, the second will be the sentinel (procname == 0).
1881 * We allocate everything in one go so that we don't have to
1882 * worry about freeing additional memory in unregister_sysctl_table.
1884 header = kzalloc(sizeof(struct ctl_table_header) +
1885 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1886 if (!header)
1887 return NULL;
1889 new = (struct ctl_table *) (header + 1);
1891 /* Now connect the dots */
1892 prevp = &header->ctl_table;
1893 for (n = 0; n < npath; ++n, ++path) {
1894 /* Copy the procname */
1895 new->procname = path->procname;
1896 new->mode = 0555;
1898 *prevp = new;
1899 prevp = &new->child;
1901 new += 2;
1903 *prevp = table;
1904 header->ctl_table_arg = table;
1906 INIT_LIST_HEAD(&header->ctl_entry);
1907 header->used = 0;
1908 header->unregistering = NULL;
1909 header->root = root;
1910 sysctl_set_parent(NULL, header->ctl_table);
1911 header->count = 1;
1912 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1913 if (sysctl_check_table(namespaces, header->ctl_table)) {
1914 kfree(header);
1915 return NULL;
1917 #endif
1918 spin_lock(&sysctl_lock);
1919 header->set = lookup_header_set(root, namespaces);
1920 header->attached_by = header->ctl_table;
1921 header->attached_to = root_table;
1922 header->parent = &root_table_header;
1923 for (set = header->set; set; set = set->parent) {
1924 struct ctl_table_header *p;
1925 list_for_each_entry(p, &set->list, ctl_entry) {
1926 if (p->unregistering)
1927 continue;
1928 try_attach(p, header);
1931 header->parent->count++;
1932 list_add_tail(&header->ctl_entry, &header->set->list);
1933 spin_unlock(&sysctl_lock);
1935 return header;
1939 * register_sysctl_table_path - register a sysctl table hierarchy
1940 * @path: The path to the directory the sysctl table is in.
1941 * @table: the top-level table structure
1943 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1944 * array. A completely 0 filled entry terminates the table.
1946 * See __register_sysctl_paths for more details.
1948 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1949 struct ctl_table *table)
1951 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1952 path, table);
1956 * register_sysctl_table - register a sysctl table hierarchy
1957 * @table: the top-level table structure
1959 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1960 * array. A completely 0 filled entry terminates the table.
1962 * See register_sysctl_paths for more details.
1964 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1966 static const struct ctl_path null_path[] = { {} };
1968 return register_sysctl_paths(null_path, table);
1972 * unregister_sysctl_table - unregister a sysctl table hierarchy
1973 * @header: the header returned from register_sysctl_table
1975 * Unregisters the sysctl table and all children. proc entries may not
1976 * actually be removed until they are no longer used by anyone.
1978 void unregister_sysctl_table(struct ctl_table_header * header)
1980 might_sleep();
1982 if (header == NULL)
1983 return;
1985 spin_lock(&sysctl_lock);
1986 start_unregistering(header);
1987 if (!--header->parent->count) {
1988 WARN_ON(1);
1989 kfree_rcu(header->parent, rcu);
1991 if (!--header->count)
1992 kfree_rcu(header, rcu);
1993 spin_unlock(&sysctl_lock);
1996 int sysctl_is_seen(struct ctl_table_header *p)
1998 struct ctl_table_set *set = p->set;
1999 int res;
2000 spin_lock(&sysctl_lock);
2001 if (p->unregistering)
2002 res = 0;
2003 else if (!set->is_seen)
2004 res = 1;
2005 else
2006 res = set->is_seen(set);
2007 spin_unlock(&sysctl_lock);
2008 return res;
2011 void setup_sysctl_set(struct ctl_table_set *p,
2012 struct ctl_table_set *parent,
2013 int (*is_seen)(struct ctl_table_set *))
2015 INIT_LIST_HEAD(&p->list);
2016 p->parent = parent ? parent : &sysctl_table_root.default_set;
2017 p->is_seen = is_seen;
2020 #else /* !CONFIG_SYSCTL */
2021 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2023 return NULL;
2026 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2027 struct ctl_table *table)
2029 return NULL;
2032 void unregister_sysctl_table(struct ctl_table_header * table)
2036 void setup_sysctl_set(struct ctl_table_set *p,
2037 struct ctl_table_set *parent,
2038 int (*is_seen)(struct ctl_table_set *))
2042 void sysctl_head_put(struct ctl_table_header *head)
2046 #endif /* CONFIG_SYSCTL */
2049 * /proc/sys support
2052 #ifdef CONFIG_PROC_SYSCTL
2054 static int _proc_do_string(void* data, int maxlen, int write,
2055 void __user *buffer,
2056 size_t *lenp, loff_t *ppos)
2058 size_t len;
2059 char __user *p;
2060 char c;
2062 if (!data || !maxlen || !*lenp) {
2063 *lenp = 0;
2064 return 0;
2067 if (write) {
2068 len = 0;
2069 p = buffer;
2070 while (len < *lenp) {
2071 if (get_user(c, p++))
2072 return -EFAULT;
2073 if (c == 0 || c == '\n')
2074 break;
2075 len++;
2077 if (len >= maxlen)
2078 len = maxlen-1;
2079 if(copy_from_user(data, buffer, len))
2080 return -EFAULT;
2081 ((char *) data)[len] = 0;
2082 *ppos += *lenp;
2083 } else {
2084 len = strlen(data);
2085 if (len > maxlen)
2086 len = maxlen;
2088 if (*ppos > len) {
2089 *lenp = 0;
2090 return 0;
2093 data += *ppos;
2094 len -= *ppos;
2096 if (len > *lenp)
2097 len = *lenp;
2098 if (len)
2099 if(copy_to_user(buffer, data, len))
2100 return -EFAULT;
2101 if (len < *lenp) {
2102 if(put_user('\n', ((char __user *) buffer) + len))
2103 return -EFAULT;
2104 len++;
2106 *lenp = len;
2107 *ppos += len;
2109 return 0;
2113 * proc_dostring - read a string sysctl
2114 * @table: the sysctl table
2115 * @write: %TRUE if this is a write to the sysctl file
2116 * @buffer: the user buffer
2117 * @lenp: the size of the user buffer
2118 * @ppos: file position
2120 * Reads/writes a string from/to the user buffer. If the kernel
2121 * buffer provided is not large enough to hold the string, the
2122 * string is truncated. The copied string is %NULL-terminated.
2123 * If the string is being read by the user process, it is copied
2124 * and a newline '\n' is added. It is truncated if the buffer is
2125 * not large enough.
2127 * Returns 0 on success.
2129 int proc_dostring(struct ctl_table *table, int write,
2130 void __user *buffer, size_t *lenp, loff_t *ppos)
2132 return _proc_do_string(table->data, table->maxlen, write,
2133 buffer, lenp, ppos);
2136 static size_t proc_skip_spaces(char **buf)
2138 size_t ret;
2139 char *tmp = skip_spaces(*buf);
2140 ret = tmp - *buf;
2141 *buf = tmp;
2142 return ret;
2145 static void proc_skip_char(char **buf, size_t *size, const char v)
2147 while (*size) {
2148 if (**buf != v)
2149 break;
2150 (*size)--;
2151 (*buf)++;
2155 #define TMPBUFLEN 22
2157 * proc_get_long - reads an ASCII formatted integer from a user buffer
2159 * @buf: a kernel buffer
2160 * @size: size of the kernel buffer
2161 * @val: this is where the number will be stored
2162 * @neg: set to %TRUE if number is negative
2163 * @perm_tr: a vector which contains the allowed trailers
2164 * @perm_tr_len: size of the perm_tr vector
2165 * @tr: pointer to store the trailer character
2167 * In case of success %0 is returned and @buf and @size are updated with
2168 * the amount of bytes read. If @tr is non-NULL and a trailing
2169 * character exists (size is non-zero after returning from this
2170 * function), @tr is updated with the trailing character.
2172 static int proc_get_long(char **buf, size_t *size,
2173 unsigned long *val, bool *neg,
2174 const char *perm_tr, unsigned perm_tr_len, char *tr)
2176 int len;
2177 char *p, tmp[TMPBUFLEN];
2179 if (!*size)
2180 return -EINVAL;
2182 len = *size;
2183 if (len > TMPBUFLEN - 1)
2184 len = TMPBUFLEN - 1;
2186 memcpy(tmp, *buf, len);
2188 tmp[len] = 0;
2189 p = tmp;
2190 if (*p == '-' && *size > 1) {
2191 *neg = true;
2192 p++;
2193 } else
2194 *neg = false;
2195 if (!isdigit(*p))
2196 return -EINVAL;
2198 *val = simple_strtoul(p, &p, 0);
2200 len = p - tmp;
2202 /* We don't know if the next char is whitespace thus we may accept
2203 * invalid integers (e.g. 1234...a) or two integers instead of one
2204 * (e.g. 123...1). So lets not allow such large numbers. */
2205 if (len == TMPBUFLEN - 1)
2206 return -EINVAL;
2208 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2209 return -EINVAL;
2211 if (tr && (len < *size))
2212 *tr = *p;
2214 *buf += len;
2215 *size -= len;
2217 return 0;
2221 * proc_put_long - converts an integer to a decimal ASCII formatted string
2223 * @buf: the user buffer
2224 * @size: the size of the user buffer
2225 * @val: the integer to be converted
2226 * @neg: sign of the number, %TRUE for negative
2228 * In case of success %0 is returned and @buf and @size are updated with
2229 * the amount of bytes written.
2231 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2232 bool neg)
2234 int len;
2235 char tmp[TMPBUFLEN], *p = tmp;
2237 sprintf(p, "%s%lu", neg ? "-" : "", val);
2238 len = strlen(tmp);
2239 if (len > *size)
2240 len = *size;
2241 if (copy_to_user(*buf, tmp, len))
2242 return -EFAULT;
2243 *size -= len;
2244 *buf += len;
2245 return 0;
2247 #undef TMPBUFLEN
2249 static int proc_put_char(void __user **buf, size_t *size, char c)
2251 if (*size) {
2252 char __user **buffer = (char __user **)buf;
2253 if (put_user(c, *buffer))
2254 return -EFAULT;
2255 (*size)--, (*buffer)++;
2256 *buf = *buffer;
2258 return 0;
2261 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2262 int *valp,
2263 int write, void *data)
2265 if (write) {
2266 *valp = *negp ? -*lvalp : *lvalp;
2267 } else {
2268 int val = *valp;
2269 if (val < 0) {
2270 *negp = true;
2271 *lvalp = (unsigned long)-val;
2272 } else {
2273 *negp = false;
2274 *lvalp = (unsigned long)val;
2277 return 0;
2280 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2282 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2283 int write, void __user *buffer,
2284 size_t *lenp, loff_t *ppos,
2285 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2286 int write, void *data),
2287 void *data)
2289 int *i, vleft, first = 1, err = 0;
2290 unsigned long page = 0;
2291 size_t left;
2292 char *kbuf;
2294 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2295 *lenp = 0;
2296 return 0;
2299 i = (int *) tbl_data;
2300 vleft = table->maxlen / sizeof(*i);
2301 left = *lenp;
2303 if (!conv)
2304 conv = do_proc_dointvec_conv;
2306 if (write) {
2307 if (left > PAGE_SIZE - 1)
2308 left = PAGE_SIZE - 1;
2309 page = __get_free_page(GFP_TEMPORARY);
2310 kbuf = (char *) page;
2311 if (!kbuf)
2312 return -ENOMEM;
2313 if (copy_from_user(kbuf, buffer, left)) {
2314 err = -EFAULT;
2315 goto free;
2317 kbuf[left] = 0;
2320 for (; left && vleft--; i++, first=0) {
2321 unsigned long lval;
2322 bool neg;
2324 if (write) {
2325 left -= proc_skip_spaces(&kbuf);
2327 if (!left)
2328 break;
2329 err = proc_get_long(&kbuf, &left, &lval, &neg,
2330 proc_wspace_sep,
2331 sizeof(proc_wspace_sep), NULL);
2332 if (err)
2333 break;
2334 if (conv(&neg, &lval, i, 1, data)) {
2335 err = -EINVAL;
2336 break;
2338 } else {
2339 if (conv(&neg, &lval, i, 0, data)) {
2340 err = -EINVAL;
2341 break;
2343 if (!first)
2344 err = proc_put_char(&buffer, &left, '\t');
2345 if (err)
2346 break;
2347 err = proc_put_long(&buffer, &left, lval, neg);
2348 if (err)
2349 break;
2353 if (!write && !first && left && !err)
2354 err = proc_put_char(&buffer, &left, '\n');
2355 if (write && !err && left)
2356 left -= proc_skip_spaces(&kbuf);
2357 free:
2358 if (write) {
2359 free_page(page);
2360 if (first)
2361 return err ? : -EINVAL;
2363 *lenp -= left;
2364 *ppos += *lenp;
2365 return err;
2368 static int do_proc_dointvec(struct ctl_table *table, int write,
2369 void __user *buffer, size_t *lenp, loff_t *ppos,
2370 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2371 int write, void *data),
2372 void *data)
2374 return __do_proc_dointvec(table->data, table, write,
2375 buffer, lenp, ppos, conv, data);
2379 * proc_dointvec - read a vector of integers
2380 * @table: the sysctl table
2381 * @write: %TRUE if this is a write to the sysctl file
2382 * @buffer: the user buffer
2383 * @lenp: the size of the user buffer
2384 * @ppos: file position
2386 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2387 * values from/to the user buffer, treated as an ASCII string.
2389 * Returns 0 on success.
2391 int proc_dointvec(struct ctl_table *table, int write,
2392 void __user *buffer, size_t *lenp, loff_t *ppos)
2394 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2395 NULL,NULL);
2399 * Taint values can only be increased
2400 * This means we can safely use a temporary.
2402 static int proc_taint(struct ctl_table *table, int write,
2403 void __user *buffer, size_t *lenp, loff_t *ppos)
2405 struct ctl_table t;
2406 unsigned long tmptaint = get_taint();
2407 int err;
2409 if (write && !capable(CAP_SYS_ADMIN))
2410 return -EPERM;
2412 t = *table;
2413 t.data = &tmptaint;
2414 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2415 if (err < 0)
2416 return err;
2418 if (write) {
2420 * Poor man's atomic or. Not worth adding a primitive
2421 * to everyone's atomic.h for this
2423 int i;
2424 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2425 if ((tmptaint >> i) & 1)
2426 add_taint(i);
2430 return err;
2433 #ifdef CONFIG_PRINTK
2434 static int proc_dmesg_restrict(struct ctl_table *table, int write,
2435 void __user *buffer, size_t *lenp, loff_t *ppos)
2437 if (write && !capable(CAP_SYS_ADMIN))
2438 return -EPERM;
2440 return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2442 #endif
2444 struct do_proc_dointvec_minmax_conv_param {
2445 int *min;
2446 int *max;
2449 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2450 int *valp,
2451 int write, void *data)
2453 struct do_proc_dointvec_minmax_conv_param *param = data;
2454 if (write) {
2455 int val = *negp ? -*lvalp : *lvalp;
2456 if ((param->min && *param->min > val) ||
2457 (param->max && *param->max < val))
2458 return -EINVAL;
2459 *valp = val;
2460 } else {
2461 int val = *valp;
2462 if (val < 0) {
2463 *negp = true;
2464 *lvalp = (unsigned long)-val;
2465 } else {
2466 *negp = false;
2467 *lvalp = (unsigned long)val;
2470 return 0;
2474 * proc_dointvec_minmax - read a vector of integers with min/max values
2475 * @table: the sysctl table
2476 * @write: %TRUE if this is a write to the sysctl file
2477 * @buffer: the user buffer
2478 * @lenp: the size of the user buffer
2479 * @ppos: file position
2481 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2482 * values from/to the user buffer, treated as an ASCII string.
2484 * This routine will ensure the values are within the range specified by
2485 * table->extra1 (min) and table->extra2 (max).
2487 * Returns 0 on success.
2489 int proc_dointvec_minmax(struct ctl_table *table, int write,
2490 void __user *buffer, size_t *lenp, loff_t *ppos)
2492 struct do_proc_dointvec_minmax_conv_param param = {
2493 .min = (int *) table->extra1,
2494 .max = (int *) table->extra2,
2496 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2497 do_proc_dointvec_minmax_conv, &param);
2500 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2501 void __user *buffer,
2502 size_t *lenp, loff_t *ppos,
2503 unsigned long convmul,
2504 unsigned long convdiv)
2506 unsigned long *i, *min, *max;
2507 int vleft, first = 1, err = 0;
2508 unsigned long page = 0;
2509 size_t left;
2510 char *kbuf;
2512 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2513 *lenp = 0;
2514 return 0;
2517 i = (unsigned long *) data;
2518 min = (unsigned long *) table->extra1;
2519 max = (unsigned long *) table->extra2;
2520 vleft = table->maxlen / sizeof(unsigned long);
2521 left = *lenp;
2523 if (write) {
2524 if (left > PAGE_SIZE - 1)
2525 left = PAGE_SIZE - 1;
2526 page = __get_free_page(GFP_TEMPORARY);
2527 kbuf = (char *) page;
2528 if (!kbuf)
2529 return -ENOMEM;
2530 if (copy_from_user(kbuf, buffer, left)) {
2531 err = -EFAULT;
2532 goto free;
2534 kbuf[left] = 0;
2537 for (; left && vleft--; i++, first = 0) {
2538 unsigned long val;
2540 if (write) {
2541 bool neg;
2543 left -= proc_skip_spaces(&kbuf);
2545 err = proc_get_long(&kbuf, &left, &val, &neg,
2546 proc_wspace_sep,
2547 sizeof(proc_wspace_sep), NULL);
2548 if (err)
2549 break;
2550 if (neg)
2551 continue;
2552 if ((min && val < *min) || (max && val > *max))
2553 continue;
2554 *i = val;
2555 } else {
2556 val = convdiv * (*i) / convmul;
2557 if (!first)
2558 err = proc_put_char(&buffer, &left, '\t');
2559 err = proc_put_long(&buffer, &left, val, false);
2560 if (err)
2561 break;
2565 if (!write && !first && left && !err)
2566 err = proc_put_char(&buffer, &left, '\n');
2567 if (write && !err)
2568 left -= proc_skip_spaces(&kbuf);
2569 free:
2570 if (write) {
2571 free_page(page);
2572 if (first)
2573 return err ? : -EINVAL;
2575 *lenp -= left;
2576 *ppos += *lenp;
2577 return err;
2580 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2581 void __user *buffer,
2582 size_t *lenp, loff_t *ppos,
2583 unsigned long convmul,
2584 unsigned long convdiv)
2586 return __do_proc_doulongvec_minmax(table->data, table, write,
2587 buffer, lenp, ppos, convmul, convdiv);
2591 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2592 * @table: the sysctl table
2593 * @write: %TRUE if this is a write to the sysctl file
2594 * @buffer: the user buffer
2595 * @lenp: the size of the user buffer
2596 * @ppos: file position
2598 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2599 * values from/to the user buffer, treated as an ASCII string.
2601 * This routine will ensure the values are within the range specified by
2602 * table->extra1 (min) and table->extra2 (max).
2604 * Returns 0 on success.
2606 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2607 void __user *buffer, size_t *lenp, loff_t *ppos)
2609 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2613 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2614 * @table: the sysctl table
2615 * @write: %TRUE if this is a write to the sysctl file
2616 * @buffer: the user buffer
2617 * @lenp: the size of the user buffer
2618 * @ppos: file position
2620 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2621 * values from/to the user buffer, treated as an ASCII string. The values
2622 * are treated as milliseconds, and converted to jiffies when they are stored.
2624 * This routine will ensure the values are within the range specified by
2625 * table->extra1 (min) and table->extra2 (max).
2627 * Returns 0 on success.
2629 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2630 void __user *buffer,
2631 size_t *lenp, loff_t *ppos)
2633 return do_proc_doulongvec_minmax(table, write, buffer,
2634 lenp, ppos, HZ, 1000l);
2638 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2639 int *valp,
2640 int write, void *data)
2642 if (write) {
2643 if (*lvalp > LONG_MAX / HZ)
2644 return 1;
2645 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2646 } else {
2647 int val = *valp;
2648 unsigned long lval;
2649 if (val < 0) {
2650 *negp = true;
2651 lval = (unsigned long)-val;
2652 } else {
2653 *negp = false;
2654 lval = (unsigned long)val;
2656 *lvalp = lval / HZ;
2658 return 0;
2661 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2662 int *valp,
2663 int write, void *data)
2665 if (write) {
2666 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2667 return 1;
2668 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2669 } else {
2670 int val = *valp;
2671 unsigned long lval;
2672 if (val < 0) {
2673 *negp = true;
2674 lval = (unsigned long)-val;
2675 } else {
2676 *negp = false;
2677 lval = (unsigned long)val;
2679 *lvalp = jiffies_to_clock_t(lval);
2681 return 0;
2684 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2685 int *valp,
2686 int write, void *data)
2688 if (write) {
2689 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2690 } else {
2691 int val = *valp;
2692 unsigned long lval;
2693 if (val < 0) {
2694 *negp = true;
2695 lval = (unsigned long)-val;
2696 } else {
2697 *negp = false;
2698 lval = (unsigned long)val;
2700 *lvalp = jiffies_to_msecs(lval);
2702 return 0;
2706 * proc_dointvec_jiffies - read a vector of integers as seconds
2707 * @table: the sysctl table
2708 * @write: %TRUE if this is a write to the sysctl file
2709 * @buffer: the user buffer
2710 * @lenp: the size of the user buffer
2711 * @ppos: file position
2713 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2714 * values from/to the user buffer, treated as an ASCII string.
2715 * The values read are assumed to be in seconds, and are converted into
2716 * jiffies.
2718 * Returns 0 on success.
2720 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2721 void __user *buffer, size_t *lenp, loff_t *ppos)
2723 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2724 do_proc_dointvec_jiffies_conv,NULL);
2728 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2729 * @table: the sysctl table
2730 * @write: %TRUE if this is a write to the sysctl file
2731 * @buffer: the user buffer
2732 * @lenp: the size of the user buffer
2733 * @ppos: pointer to the file position
2735 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2736 * values from/to the user buffer, treated as an ASCII string.
2737 * The values read are assumed to be in 1/USER_HZ seconds, and
2738 * are converted into jiffies.
2740 * Returns 0 on success.
2742 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2743 void __user *buffer, size_t *lenp, loff_t *ppos)
2745 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2746 do_proc_dointvec_userhz_jiffies_conv,NULL);
2750 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2751 * @table: the sysctl table
2752 * @write: %TRUE if this is a write to the sysctl file
2753 * @buffer: the user buffer
2754 * @lenp: the size of the user buffer
2755 * @ppos: file position
2756 * @ppos: the current position in the file
2758 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2759 * values from/to the user buffer, treated as an ASCII string.
2760 * The values read are assumed to be in 1/1000 seconds, and
2761 * are converted into jiffies.
2763 * Returns 0 on success.
2765 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2766 void __user *buffer, size_t *lenp, loff_t *ppos)
2768 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2769 do_proc_dointvec_ms_jiffies_conv, NULL);
2772 static int proc_do_cad_pid(struct ctl_table *table, int write,
2773 void __user *buffer, size_t *lenp, loff_t *ppos)
2775 struct pid *new_pid;
2776 pid_t tmp;
2777 int r;
2779 tmp = pid_vnr(cad_pid);
2781 r = __do_proc_dointvec(&tmp, table, write, buffer,
2782 lenp, ppos, NULL, NULL);
2783 if (r || !write)
2784 return r;
2786 new_pid = find_get_pid(tmp);
2787 if (!new_pid)
2788 return -ESRCH;
2790 put_pid(xchg(&cad_pid, new_pid));
2791 return 0;
2795 * proc_do_large_bitmap - read/write from/to a large bitmap
2796 * @table: the sysctl table
2797 * @write: %TRUE if this is a write to the sysctl file
2798 * @buffer: the user buffer
2799 * @lenp: the size of the user buffer
2800 * @ppos: file position
2802 * The bitmap is stored at table->data and the bitmap length (in bits)
2803 * in table->maxlen.
2805 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2806 * large bitmaps may be represented in a compact manner. Writing into
2807 * the file will clear the bitmap then update it with the given input.
2809 * Returns 0 on success.
2811 int proc_do_large_bitmap(struct ctl_table *table, int write,
2812 void __user *buffer, size_t *lenp, loff_t *ppos)
2814 int err = 0;
2815 bool first = 1;
2816 size_t left = *lenp;
2817 unsigned long bitmap_len = table->maxlen;
2818 unsigned long *bitmap = (unsigned long *) table->data;
2819 unsigned long *tmp_bitmap = NULL;
2820 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2822 if (!bitmap_len || !left || (*ppos && !write)) {
2823 *lenp = 0;
2824 return 0;
2827 if (write) {
2828 unsigned long page = 0;
2829 char *kbuf;
2831 if (left > PAGE_SIZE - 1)
2832 left = PAGE_SIZE - 1;
2834 page = __get_free_page(GFP_TEMPORARY);
2835 kbuf = (char *) page;
2836 if (!kbuf)
2837 return -ENOMEM;
2838 if (copy_from_user(kbuf, buffer, left)) {
2839 free_page(page);
2840 return -EFAULT;
2842 kbuf[left] = 0;
2844 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2845 GFP_KERNEL);
2846 if (!tmp_bitmap) {
2847 free_page(page);
2848 return -ENOMEM;
2850 proc_skip_char(&kbuf, &left, '\n');
2851 while (!err && left) {
2852 unsigned long val_a, val_b;
2853 bool neg;
2855 err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2856 sizeof(tr_a), &c);
2857 if (err)
2858 break;
2859 if (val_a >= bitmap_len || neg) {
2860 err = -EINVAL;
2861 break;
2864 val_b = val_a;
2865 if (left) {
2866 kbuf++;
2867 left--;
2870 if (c == '-') {
2871 err = proc_get_long(&kbuf, &left, &val_b,
2872 &neg, tr_b, sizeof(tr_b),
2873 &c);
2874 if (err)
2875 break;
2876 if (val_b >= bitmap_len || neg ||
2877 val_a > val_b) {
2878 err = -EINVAL;
2879 break;
2881 if (left) {
2882 kbuf++;
2883 left--;
2887 while (val_a <= val_b)
2888 set_bit(val_a++, tmp_bitmap);
2890 first = 0;
2891 proc_skip_char(&kbuf, &left, '\n');
2893 free_page(page);
2894 } else {
2895 unsigned long bit_a, bit_b = 0;
2897 while (left) {
2898 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2899 if (bit_a >= bitmap_len)
2900 break;
2901 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2902 bit_a + 1) - 1;
2904 if (!first) {
2905 err = proc_put_char(&buffer, &left, ',');
2906 if (err)
2907 break;
2909 err = proc_put_long(&buffer, &left, bit_a, false);
2910 if (err)
2911 break;
2912 if (bit_a != bit_b) {
2913 err = proc_put_char(&buffer, &left, '-');
2914 if (err)
2915 break;
2916 err = proc_put_long(&buffer, &left, bit_b, false);
2917 if (err)
2918 break;
2921 first = 0; bit_b++;
2923 if (!err)
2924 err = proc_put_char(&buffer, &left, '\n');
2927 if (!err) {
2928 if (write) {
2929 if (*ppos)
2930 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2931 else
2932 memcpy(bitmap, tmp_bitmap,
2933 BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
2935 kfree(tmp_bitmap);
2936 *lenp -= left;
2937 *ppos += *lenp;
2938 return 0;
2939 } else {
2940 kfree(tmp_bitmap);
2941 return err;
2945 #else /* CONFIG_PROC_SYSCTL */
2947 int proc_dostring(struct ctl_table *table, int write,
2948 void __user *buffer, size_t *lenp, loff_t *ppos)
2950 return -ENOSYS;
2953 int proc_dointvec(struct ctl_table *table, int write,
2954 void __user *buffer, size_t *lenp, loff_t *ppos)
2956 return -ENOSYS;
2959 int proc_dointvec_minmax(struct ctl_table *table, int write,
2960 void __user *buffer, size_t *lenp, loff_t *ppos)
2962 return -ENOSYS;
2965 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2966 void __user *buffer, size_t *lenp, loff_t *ppos)
2968 return -ENOSYS;
2971 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2972 void __user *buffer, size_t *lenp, loff_t *ppos)
2974 return -ENOSYS;
2977 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2978 void __user *buffer, size_t *lenp, loff_t *ppos)
2980 return -ENOSYS;
2983 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2984 void __user *buffer, size_t *lenp, loff_t *ppos)
2986 return -ENOSYS;
2989 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2990 void __user *buffer,
2991 size_t *lenp, loff_t *ppos)
2993 return -ENOSYS;
2997 #endif /* CONFIG_PROC_SYSCTL */
3000 * No sense putting this after each symbol definition, twice,
3001 * exception granted :-)
3003 EXPORT_SYMBOL(proc_dointvec);
3004 EXPORT_SYMBOL(proc_dointvec_jiffies);
3005 EXPORT_SYMBOL(proc_dointvec_minmax);
3006 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3007 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3008 EXPORT_SYMBOL(proc_dostring);
3009 EXPORT_SYMBOL(proc_doulongvec_minmax);
3010 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3011 EXPORT_SYMBOL(register_sysctl_table);
3012 EXPORT_SYMBOL(register_sysctl_paths);
3013 EXPORT_SYMBOL(unregister_sysctl_table);