NFSv4.1: Fix a request leak on the back channel
[linux/fpc-iii.git] / kernel / sysctl.c
blobea7ec7f197c48484deb2b61fa2288a3eacfb7760
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_dointvec_minmax_sysadmin(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_sysadmin,
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_dointvec_minmax_sysadmin,
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,
807 .procname = "bootloader_type",
808 .data = &bootloader_type,
809 .maxlen = sizeof (int),
810 .mode = 0444,
811 .proc_handler = proc_dointvec,
814 .procname = "bootloader_version",
815 .data = &bootloader_version,
816 .maxlen = sizeof (int),
817 .mode = 0444,
818 .proc_handler = proc_dointvec,
821 .procname = "kstack_depth_to_print",
822 .data = &kstack_depth_to_print,
823 .maxlen = sizeof(int),
824 .mode = 0644,
825 .proc_handler = proc_dointvec,
828 .procname = "io_delay_type",
829 .data = &io_delay_type,
830 .maxlen = sizeof(int),
831 .mode = 0644,
832 .proc_handler = proc_dointvec,
834 #endif
835 #if defined(CONFIG_MMU)
837 .procname = "randomize_va_space",
838 .data = &randomize_va_space,
839 .maxlen = sizeof(int),
840 .mode = 0644,
841 .proc_handler = proc_dointvec,
843 #endif
844 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
846 .procname = "spin_retry",
847 .data = &spin_retry,
848 .maxlen = sizeof (int),
849 .mode = 0644,
850 .proc_handler = proc_dointvec,
852 #endif
853 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
855 .procname = "acpi_video_flags",
856 .data = &acpi_realmode_flags,
857 .maxlen = sizeof (unsigned long),
858 .mode = 0644,
859 .proc_handler = proc_doulongvec_minmax,
861 #endif
862 #ifdef CONFIG_IA64
864 .procname = "ignore-unaligned-usertrap",
865 .data = &no_unaligned_warning,
866 .maxlen = sizeof (int),
867 .mode = 0644,
868 .proc_handler = proc_dointvec,
871 .procname = "unaligned-dump-stack",
872 .data = &unaligned_dump_stack,
873 .maxlen = sizeof (int),
874 .mode = 0644,
875 .proc_handler = proc_dointvec,
877 #endif
878 #ifdef CONFIG_DETECT_HUNG_TASK
880 .procname = "hung_task_panic",
881 .data = &sysctl_hung_task_panic,
882 .maxlen = sizeof(int),
883 .mode = 0644,
884 .proc_handler = proc_dointvec_minmax,
885 .extra1 = &zero,
886 .extra2 = &one,
889 .procname = "hung_task_check_count",
890 .data = &sysctl_hung_task_check_count,
891 .maxlen = sizeof(unsigned long),
892 .mode = 0644,
893 .proc_handler = proc_doulongvec_minmax,
896 .procname = "hung_task_timeout_secs",
897 .data = &sysctl_hung_task_timeout_secs,
898 .maxlen = sizeof(unsigned long),
899 .mode = 0644,
900 .proc_handler = proc_dohung_task_timeout_secs,
903 .procname = "hung_task_warnings",
904 .data = &sysctl_hung_task_warnings,
905 .maxlen = sizeof(unsigned long),
906 .mode = 0644,
907 .proc_handler = proc_doulongvec_minmax,
909 #endif
910 #ifdef CONFIG_COMPAT
912 .procname = "compat-log",
913 .data = &compat_log,
914 .maxlen = sizeof (int),
915 .mode = 0644,
916 .proc_handler = proc_dointvec,
918 #endif
919 #ifdef CONFIG_RT_MUTEXES
921 .procname = "max_lock_depth",
922 .data = &max_lock_depth,
923 .maxlen = sizeof(int),
924 .mode = 0644,
925 .proc_handler = proc_dointvec,
927 #endif
929 .procname = "poweroff_cmd",
930 .data = &poweroff_cmd,
931 .maxlen = POWEROFF_CMD_PATH_LEN,
932 .mode = 0644,
933 .proc_handler = proc_dostring,
935 #ifdef CONFIG_KEYS
937 .procname = "keys",
938 .mode = 0555,
939 .child = key_sysctls,
941 #endif
942 #ifdef CONFIG_RCU_TORTURE_TEST
944 .procname = "rcutorture_runnable",
945 .data = &rcutorture_runnable,
946 .maxlen = sizeof(int),
947 .mode = 0644,
948 .proc_handler = proc_dointvec,
950 #endif
951 #ifdef CONFIG_PERF_EVENTS
953 * User-space scripts rely on the existence of this file
954 * as a feature check for perf_events being enabled.
956 * So it's an ABI, do not remove!
959 .procname = "perf_event_paranoid",
960 .data = &sysctl_perf_event_paranoid,
961 .maxlen = sizeof(sysctl_perf_event_paranoid),
962 .mode = 0644,
963 .proc_handler = proc_dointvec,
966 .procname = "perf_event_mlock_kb",
967 .data = &sysctl_perf_event_mlock,
968 .maxlen = sizeof(sysctl_perf_event_mlock),
969 .mode = 0644,
970 .proc_handler = proc_dointvec,
973 .procname = "perf_event_max_sample_rate",
974 .data = &sysctl_perf_event_sample_rate,
975 .maxlen = sizeof(sysctl_perf_event_sample_rate),
976 .mode = 0644,
977 .proc_handler = perf_proc_update_handler,
979 #endif
980 #ifdef CONFIG_KMEMCHECK
982 .procname = "kmemcheck",
983 .data = &kmemcheck_enabled,
984 .maxlen = sizeof(int),
985 .mode = 0644,
986 .proc_handler = proc_dointvec,
988 #endif
989 #ifdef CONFIG_BLOCK
991 .procname = "blk_iopoll",
992 .data = &blk_iopoll_enabled,
993 .maxlen = sizeof(int),
994 .mode = 0644,
995 .proc_handler = proc_dointvec,
997 #endif
1001 static struct ctl_table vm_table[] = {
1003 .procname = "overcommit_memory",
1004 .data = &sysctl_overcommit_memory,
1005 .maxlen = sizeof(sysctl_overcommit_memory),
1006 .mode = 0644,
1007 .proc_handler = proc_dointvec_minmax,
1008 .extra1 = &zero,
1009 .extra2 = &two,
1012 .procname = "panic_on_oom",
1013 .data = &sysctl_panic_on_oom,
1014 .maxlen = sizeof(sysctl_panic_on_oom),
1015 .mode = 0644,
1016 .proc_handler = proc_dointvec_minmax,
1017 .extra1 = &zero,
1018 .extra2 = &two,
1021 .procname = "oom_kill_allocating_task",
1022 .data = &sysctl_oom_kill_allocating_task,
1023 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1024 .mode = 0644,
1025 .proc_handler = proc_dointvec,
1028 .procname = "oom_dump_tasks",
1029 .data = &sysctl_oom_dump_tasks,
1030 .maxlen = sizeof(sysctl_oom_dump_tasks),
1031 .mode = 0644,
1032 .proc_handler = proc_dointvec,
1035 .procname = "overcommit_ratio",
1036 .data = &sysctl_overcommit_ratio,
1037 .maxlen = sizeof(sysctl_overcommit_ratio),
1038 .mode = 0644,
1039 .proc_handler = proc_dointvec,
1042 .procname = "page-cluster",
1043 .data = &page_cluster,
1044 .maxlen = sizeof(int),
1045 .mode = 0644,
1046 .proc_handler = proc_dointvec_minmax,
1047 .extra1 = &zero,
1050 .procname = "dirty_background_ratio",
1051 .data = &dirty_background_ratio,
1052 .maxlen = sizeof(dirty_background_ratio),
1053 .mode = 0644,
1054 .proc_handler = dirty_background_ratio_handler,
1055 .extra1 = &zero,
1056 .extra2 = &one_hundred,
1059 .procname = "dirty_background_bytes",
1060 .data = &dirty_background_bytes,
1061 .maxlen = sizeof(dirty_background_bytes),
1062 .mode = 0644,
1063 .proc_handler = dirty_background_bytes_handler,
1064 .extra1 = &one_ul,
1067 .procname = "dirty_ratio",
1068 .data = &vm_dirty_ratio,
1069 .maxlen = sizeof(vm_dirty_ratio),
1070 .mode = 0644,
1071 .proc_handler = dirty_ratio_handler,
1072 .extra1 = &zero,
1073 .extra2 = &one_hundred,
1076 .procname = "dirty_bytes",
1077 .data = &vm_dirty_bytes,
1078 .maxlen = sizeof(vm_dirty_bytes),
1079 .mode = 0644,
1080 .proc_handler = dirty_bytes_handler,
1081 .extra1 = &dirty_bytes_min,
1084 .procname = "dirty_writeback_centisecs",
1085 .data = &dirty_writeback_interval,
1086 .maxlen = sizeof(dirty_writeback_interval),
1087 .mode = 0644,
1088 .proc_handler = dirty_writeback_centisecs_handler,
1091 .procname = "dirty_expire_centisecs",
1092 .data = &dirty_expire_interval,
1093 .maxlen = sizeof(dirty_expire_interval),
1094 .mode = 0644,
1095 .proc_handler = proc_dointvec_minmax,
1096 .extra1 = &zero,
1099 .procname = "nr_pdflush_threads",
1100 .data = &nr_pdflush_threads,
1101 .maxlen = sizeof nr_pdflush_threads,
1102 .mode = 0444 /* read-only*/,
1103 .proc_handler = proc_dointvec,
1106 .procname = "swappiness",
1107 .data = &vm_swappiness,
1108 .maxlen = sizeof(vm_swappiness),
1109 .mode = 0644,
1110 .proc_handler = proc_dointvec_minmax,
1111 .extra1 = &zero,
1112 .extra2 = &one_hundred,
1114 #ifdef CONFIG_HUGETLB_PAGE
1116 .procname = "nr_hugepages",
1117 .data = NULL,
1118 .maxlen = sizeof(unsigned long),
1119 .mode = 0644,
1120 .proc_handler = hugetlb_sysctl_handler,
1121 .extra1 = (void *)&hugetlb_zero,
1122 .extra2 = (void *)&hugetlb_infinity,
1124 #ifdef CONFIG_NUMA
1126 .procname = "nr_hugepages_mempolicy",
1127 .data = NULL,
1128 .maxlen = sizeof(unsigned long),
1129 .mode = 0644,
1130 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1131 .extra1 = (void *)&hugetlb_zero,
1132 .extra2 = (void *)&hugetlb_infinity,
1134 #endif
1136 .procname = "hugetlb_shm_group",
1137 .data = &sysctl_hugetlb_shm_group,
1138 .maxlen = sizeof(gid_t),
1139 .mode = 0644,
1140 .proc_handler = proc_dointvec,
1143 .procname = "hugepages_treat_as_movable",
1144 .data = &hugepages_treat_as_movable,
1145 .maxlen = sizeof(int),
1146 .mode = 0644,
1147 .proc_handler = hugetlb_treat_movable_handler,
1150 .procname = "nr_overcommit_hugepages",
1151 .data = NULL,
1152 .maxlen = sizeof(unsigned long),
1153 .mode = 0644,
1154 .proc_handler = hugetlb_overcommit_handler,
1155 .extra1 = (void *)&hugetlb_zero,
1156 .extra2 = (void *)&hugetlb_infinity,
1158 #endif
1160 .procname = "lowmem_reserve_ratio",
1161 .data = &sysctl_lowmem_reserve_ratio,
1162 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1163 .mode = 0644,
1164 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1167 .procname = "drop_caches",
1168 .data = &sysctl_drop_caches,
1169 .maxlen = sizeof(int),
1170 .mode = 0644,
1171 .proc_handler = drop_caches_sysctl_handler,
1172 .extra1 = &one,
1173 .extra2 = &three,
1175 #ifdef CONFIG_COMPACTION
1177 .procname = "compact_memory",
1178 .data = &sysctl_compact_memory,
1179 .maxlen = sizeof(int),
1180 .mode = 0200,
1181 .proc_handler = sysctl_compaction_handler,
1184 .procname = "extfrag_threshold",
1185 .data = &sysctl_extfrag_threshold,
1186 .maxlen = sizeof(int),
1187 .mode = 0644,
1188 .proc_handler = sysctl_extfrag_handler,
1189 .extra1 = &min_extfrag_threshold,
1190 .extra2 = &max_extfrag_threshold,
1193 #endif /* CONFIG_COMPACTION */
1195 .procname = "min_free_kbytes",
1196 .data = &min_free_kbytes,
1197 .maxlen = sizeof(min_free_kbytes),
1198 .mode = 0644,
1199 .proc_handler = min_free_kbytes_sysctl_handler,
1200 .extra1 = &zero,
1203 .procname = "percpu_pagelist_fraction",
1204 .data = &percpu_pagelist_fraction,
1205 .maxlen = sizeof(percpu_pagelist_fraction),
1206 .mode = 0644,
1207 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1208 .extra1 = &min_percpu_pagelist_fract,
1210 #ifdef CONFIG_MMU
1212 .procname = "max_map_count",
1213 .data = &sysctl_max_map_count,
1214 .maxlen = sizeof(sysctl_max_map_count),
1215 .mode = 0644,
1216 .proc_handler = proc_dointvec_minmax,
1217 .extra1 = &zero,
1219 #else
1221 .procname = "nr_trim_pages",
1222 .data = &sysctl_nr_trim_pages,
1223 .maxlen = sizeof(sysctl_nr_trim_pages),
1224 .mode = 0644,
1225 .proc_handler = proc_dointvec_minmax,
1226 .extra1 = &zero,
1228 #endif
1230 .procname = "laptop_mode",
1231 .data = &laptop_mode,
1232 .maxlen = sizeof(laptop_mode),
1233 .mode = 0644,
1234 .proc_handler = proc_dointvec_jiffies,
1237 .procname = "block_dump",
1238 .data = &block_dump,
1239 .maxlen = sizeof(block_dump),
1240 .mode = 0644,
1241 .proc_handler = proc_dointvec,
1242 .extra1 = &zero,
1245 .procname = "vfs_cache_pressure",
1246 .data = &sysctl_vfs_cache_pressure,
1247 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1248 .mode = 0644,
1249 .proc_handler = proc_dointvec,
1250 .extra1 = &zero,
1252 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1254 .procname = "legacy_va_layout",
1255 .data = &sysctl_legacy_va_layout,
1256 .maxlen = sizeof(sysctl_legacy_va_layout),
1257 .mode = 0644,
1258 .proc_handler = proc_dointvec,
1259 .extra1 = &zero,
1261 #endif
1262 #ifdef CONFIG_NUMA
1264 .procname = "zone_reclaim_mode",
1265 .data = &zone_reclaim_mode,
1266 .maxlen = sizeof(zone_reclaim_mode),
1267 .mode = 0644,
1268 .proc_handler = proc_dointvec,
1269 .extra1 = &zero,
1272 .procname = "min_unmapped_ratio",
1273 .data = &sysctl_min_unmapped_ratio,
1274 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1275 .mode = 0644,
1276 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1277 .extra1 = &zero,
1278 .extra2 = &one_hundred,
1281 .procname = "min_slab_ratio",
1282 .data = &sysctl_min_slab_ratio,
1283 .maxlen = sizeof(sysctl_min_slab_ratio),
1284 .mode = 0644,
1285 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1286 .extra1 = &zero,
1287 .extra2 = &one_hundred,
1289 #endif
1290 #ifdef CONFIG_SMP
1292 .procname = "stat_interval",
1293 .data = &sysctl_stat_interval,
1294 .maxlen = sizeof(sysctl_stat_interval),
1295 .mode = 0644,
1296 .proc_handler = proc_dointvec_jiffies,
1298 #endif
1299 #ifdef CONFIG_MMU
1301 .procname = "mmap_min_addr",
1302 .data = &dac_mmap_min_addr,
1303 .maxlen = sizeof(unsigned long),
1304 .mode = 0644,
1305 .proc_handler = mmap_min_addr_handler,
1307 #endif
1308 #ifdef CONFIG_NUMA
1310 .procname = "numa_zonelist_order",
1311 .data = &numa_zonelist_order,
1312 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1313 .mode = 0644,
1314 .proc_handler = numa_zonelist_order_handler,
1316 #endif
1317 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1318 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1320 .procname = "vdso_enabled",
1321 .data = &vdso_enabled,
1322 .maxlen = sizeof(vdso_enabled),
1323 .mode = 0644,
1324 .proc_handler = proc_dointvec,
1325 .extra1 = &zero,
1327 #endif
1328 #ifdef CONFIG_HIGHMEM
1330 .procname = "highmem_is_dirtyable",
1331 .data = &vm_highmem_is_dirtyable,
1332 .maxlen = sizeof(vm_highmem_is_dirtyable),
1333 .mode = 0644,
1334 .proc_handler = proc_dointvec_minmax,
1335 .extra1 = &zero,
1336 .extra2 = &one,
1338 #endif
1340 .procname = "scan_unevictable_pages",
1341 .data = &scan_unevictable_pages,
1342 .maxlen = sizeof(scan_unevictable_pages),
1343 .mode = 0644,
1344 .proc_handler = scan_unevictable_handler,
1346 #ifdef CONFIG_MEMORY_FAILURE
1348 .procname = "memory_failure_early_kill",
1349 .data = &sysctl_memory_failure_early_kill,
1350 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1351 .mode = 0644,
1352 .proc_handler = proc_dointvec_minmax,
1353 .extra1 = &zero,
1354 .extra2 = &one,
1357 .procname = "memory_failure_recovery",
1358 .data = &sysctl_memory_failure_recovery,
1359 .maxlen = sizeof(sysctl_memory_failure_recovery),
1360 .mode = 0644,
1361 .proc_handler = proc_dointvec_minmax,
1362 .extra1 = &zero,
1363 .extra2 = &one,
1365 #endif
1369 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1370 static struct ctl_table binfmt_misc_table[] = {
1373 #endif
1375 static struct ctl_table fs_table[] = {
1377 .procname = "inode-nr",
1378 .data = &inodes_stat,
1379 .maxlen = 2*sizeof(int),
1380 .mode = 0444,
1381 .proc_handler = proc_nr_inodes,
1384 .procname = "inode-state",
1385 .data = &inodes_stat,
1386 .maxlen = 7*sizeof(int),
1387 .mode = 0444,
1388 .proc_handler = proc_nr_inodes,
1391 .procname = "file-nr",
1392 .data = &files_stat,
1393 .maxlen = sizeof(files_stat),
1394 .mode = 0444,
1395 .proc_handler = proc_nr_files,
1398 .procname = "file-max",
1399 .data = &files_stat.max_files,
1400 .maxlen = sizeof(files_stat.max_files),
1401 .mode = 0644,
1402 .proc_handler = proc_doulongvec_minmax,
1405 .procname = "nr_open",
1406 .data = &sysctl_nr_open,
1407 .maxlen = sizeof(int),
1408 .mode = 0644,
1409 .proc_handler = proc_dointvec_minmax,
1410 .extra1 = &sysctl_nr_open_min,
1411 .extra2 = &sysctl_nr_open_max,
1414 .procname = "dentry-state",
1415 .data = &dentry_stat,
1416 .maxlen = 6*sizeof(int),
1417 .mode = 0444,
1418 .proc_handler = proc_nr_dentry,
1421 .procname = "overflowuid",
1422 .data = &fs_overflowuid,
1423 .maxlen = sizeof(int),
1424 .mode = 0644,
1425 .proc_handler = proc_dointvec_minmax,
1426 .extra1 = &minolduid,
1427 .extra2 = &maxolduid,
1430 .procname = "overflowgid",
1431 .data = &fs_overflowgid,
1432 .maxlen = sizeof(int),
1433 .mode = 0644,
1434 .proc_handler = proc_dointvec_minmax,
1435 .extra1 = &minolduid,
1436 .extra2 = &maxolduid,
1438 #ifdef CONFIG_FILE_LOCKING
1440 .procname = "leases-enable",
1441 .data = &leases_enable,
1442 .maxlen = sizeof(int),
1443 .mode = 0644,
1444 .proc_handler = proc_dointvec,
1446 #endif
1447 #ifdef CONFIG_DNOTIFY
1449 .procname = "dir-notify-enable",
1450 .data = &dir_notify_enable,
1451 .maxlen = sizeof(int),
1452 .mode = 0644,
1453 .proc_handler = proc_dointvec,
1455 #endif
1456 #ifdef CONFIG_MMU
1457 #ifdef CONFIG_FILE_LOCKING
1459 .procname = "lease-break-time",
1460 .data = &lease_break_time,
1461 .maxlen = sizeof(int),
1462 .mode = 0644,
1463 .proc_handler = proc_dointvec,
1465 #endif
1466 #ifdef CONFIG_AIO
1468 .procname = "aio-nr",
1469 .data = &aio_nr,
1470 .maxlen = sizeof(aio_nr),
1471 .mode = 0444,
1472 .proc_handler = proc_doulongvec_minmax,
1475 .procname = "aio-max-nr",
1476 .data = &aio_max_nr,
1477 .maxlen = sizeof(aio_max_nr),
1478 .mode = 0644,
1479 .proc_handler = proc_doulongvec_minmax,
1481 #endif /* CONFIG_AIO */
1482 #ifdef CONFIG_INOTIFY_USER
1484 .procname = "inotify",
1485 .mode = 0555,
1486 .child = inotify_table,
1488 #endif
1489 #ifdef CONFIG_EPOLL
1491 .procname = "epoll",
1492 .mode = 0555,
1493 .child = epoll_table,
1495 #endif
1496 #endif
1498 .procname = "suid_dumpable",
1499 .data = &suid_dumpable,
1500 .maxlen = sizeof(int),
1501 .mode = 0644,
1502 .proc_handler = proc_dointvec_minmax,
1503 .extra1 = &zero,
1504 .extra2 = &two,
1506 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1508 .procname = "binfmt_misc",
1509 .mode = 0555,
1510 .child = binfmt_misc_table,
1512 #endif
1514 .procname = "pipe-max-size",
1515 .data = &pipe_max_size,
1516 .maxlen = sizeof(int),
1517 .mode = 0644,
1518 .proc_handler = &pipe_proc_fn,
1519 .extra1 = &pipe_min_size,
1524 static struct ctl_table debug_table[] = {
1525 #if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_SPARC) || \
1526 defined(CONFIG_S390) || defined(CONFIG_TILE)
1528 .procname = "exception-trace",
1529 .data = &show_unhandled_signals,
1530 .maxlen = sizeof(int),
1531 .mode = 0644,
1532 .proc_handler = proc_dointvec
1534 #endif
1535 #if defined(CONFIG_OPTPROBES)
1537 .procname = "kprobes-optimization",
1538 .data = &sysctl_kprobes_optimization,
1539 .maxlen = sizeof(int),
1540 .mode = 0644,
1541 .proc_handler = proc_kprobes_optimization_handler,
1542 .extra1 = &zero,
1543 .extra2 = &one,
1545 #endif
1549 static struct ctl_table dev_table[] = {
1553 static DEFINE_SPINLOCK(sysctl_lock);
1555 /* called under sysctl_lock */
1556 static int use_table(struct ctl_table_header *p)
1558 if (unlikely(p->unregistering))
1559 return 0;
1560 p->used++;
1561 return 1;
1564 /* called under sysctl_lock */
1565 static void unuse_table(struct ctl_table_header *p)
1567 if (!--p->used)
1568 if (unlikely(p->unregistering))
1569 complete(p->unregistering);
1572 /* called under sysctl_lock, will reacquire if has to wait */
1573 static void start_unregistering(struct ctl_table_header *p)
1576 * if p->used is 0, nobody will ever touch that entry again;
1577 * we'll eliminate all paths to it before dropping sysctl_lock
1579 if (unlikely(p->used)) {
1580 struct completion wait;
1581 init_completion(&wait);
1582 p->unregistering = &wait;
1583 spin_unlock(&sysctl_lock);
1584 wait_for_completion(&wait);
1585 spin_lock(&sysctl_lock);
1586 } else {
1587 /* anything non-NULL; we'll never dereference it */
1588 p->unregistering = ERR_PTR(-EINVAL);
1591 * do not remove from the list until nobody holds it; walking the
1592 * list in do_sysctl() relies on that.
1594 list_del_init(&p->ctl_entry);
1597 void sysctl_head_get(struct ctl_table_header *head)
1599 spin_lock(&sysctl_lock);
1600 head->count++;
1601 spin_unlock(&sysctl_lock);
1604 void sysctl_head_put(struct ctl_table_header *head)
1606 spin_lock(&sysctl_lock);
1607 if (!--head->count)
1608 kfree_rcu(head, rcu);
1609 spin_unlock(&sysctl_lock);
1612 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1614 if (!head)
1615 BUG();
1616 spin_lock(&sysctl_lock);
1617 if (!use_table(head))
1618 head = ERR_PTR(-ENOENT);
1619 spin_unlock(&sysctl_lock);
1620 return head;
1623 void sysctl_head_finish(struct ctl_table_header *head)
1625 if (!head)
1626 return;
1627 spin_lock(&sysctl_lock);
1628 unuse_table(head);
1629 spin_unlock(&sysctl_lock);
1632 static struct ctl_table_set *
1633 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1635 struct ctl_table_set *set = &root->default_set;
1636 if (root->lookup)
1637 set = root->lookup(root, namespaces);
1638 return set;
1641 static struct list_head *
1642 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1644 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1645 return &set->list;
1648 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1649 struct ctl_table_header *prev)
1651 struct ctl_table_root *root;
1652 struct list_head *header_list;
1653 struct ctl_table_header *head;
1654 struct list_head *tmp;
1656 spin_lock(&sysctl_lock);
1657 if (prev) {
1658 head = prev;
1659 tmp = &prev->ctl_entry;
1660 unuse_table(prev);
1661 goto next;
1663 tmp = &root_table_header.ctl_entry;
1664 for (;;) {
1665 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1667 if (!use_table(head))
1668 goto next;
1669 spin_unlock(&sysctl_lock);
1670 return head;
1671 next:
1672 root = head->root;
1673 tmp = tmp->next;
1674 header_list = lookup_header_list(root, namespaces);
1675 if (tmp != header_list)
1676 continue;
1678 do {
1679 root = list_entry(root->root_list.next,
1680 struct ctl_table_root, root_list);
1681 if (root == &sysctl_table_root)
1682 goto out;
1683 header_list = lookup_header_list(root, namespaces);
1684 } while (list_empty(header_list));
1685 tmp = header_list->next;
1687 out:
1688 spin_unlock(&sysctl_lock);
1689 return NULL;
1692 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1694 return __sysctl_head_next(current->nsproxy, prev);
1697 void register_sysctl_root(struct ctl_table_root *root)
1699 spin_lock(&sysctl_lock);
1700 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1701 spin_unlock(&sysctl_lock);
1705 * sysctl_perm does NOT grant the superuser all rights automatically, because
1706 * some sysctl variables are readonly even to root.
1709 static int test_perm(int mode, int op)
1711 if (!current_euid())
1712 mode >>= 6;
1713 else if (in_egroup_p(0))
1714 mode >>= 3;
1715 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1716 return 0;
1717 return -EACCES;
1720 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1722 int mode;
1724 if (root->permissions)
1725 mode = root->permissions(root, current->nsproxy, table);
1726 else
1727 mode = table->mode;
1729 return test_perm(mode, op);
1732 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1734 for (; table->procname; table++) {
1735 table->parent = parent;
1736 if (table->child)
1737 sysctl_set_parent(table, table->child);
1741 static __init int sysctl_init(void)
1743 sysctl_set_parent(NULL, root_table);
1744 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1745 sysctl_check_table(current->nsproxy, root_table);
1746 #endif
1747 return 0;
1750 core_initcall(sysctl_init);
1752 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1753 struct ctl_table *table)
1755 struct ctl_table *p;
1756 const char *s = branch->procname;
1758 /* branch should have named subdirectory as its first element */
1759 if (!s || !branch->child)
1760 return NULL;
1762 /* ... and nothing else */
1763 if (branch[1].procname)
1764 return NULL;
1766 /* table should contain subdirectory with the same name */
1767 for (p = table; p->procname; p++) {
1768 if (!p->child)
1769 continue;
1770 if (p->procname && strcmp(p->procname, s) == 0)
1771 return p;
1773 return NULL;
1776 /* see if attaching q to p would be an improvement */
1777 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1779 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1780 struct ctl_table *next;
1781 int is_better = 0;
1782 int not_in_parent = !p->attached_by;
1784 while ((next = is_branch_in(by, to)) != NULL) {
1785 if (by == q->attached_by)
1786 is_better = 1;
1787 if (to == p->attached_by)
1788 not_in_parent = 1;
1789 by = by->child;
1790 to = next->child;
1793 if (is_better && not_in_parent) {
1794 q->attached_by = by;
1795 q->attached_to = to;
1796 q->parent = p;
1801 * __register_sysctl_paths - register a sysctl hierarchy
1802 * @root: List of sysctl headers to register on
1803 * @namespaces: Data to compute which lists of sysctl entries are visible
1804 * @path: The path to the directory the sysctl table is in.
1805 * @table: the top-level table structure
1807 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1808 * array. A completely 0 filled entry terminates the table.
1810 * The members of the &struct ctl_table structure are used as follows:
1812 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1813 * enter a sysctl file
1815 * data - a pointer to data for use by proc_handler
1817 * maxlen - the maximum size in bytes of the data
1819 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1821 * child - a pointer to the child sysctl table if this entry is a directory, or
1822 * %NULL.
1824 * proc_handler - the text handler routine (described below)
1826 * de - for internal use by the sysctl routines
1828 * extra1, extra2 - extra pointers usable by the proc handler routines
1830 * Leaf nodes in the sysctl tree will be represented by a single file
1831 * under /proc; non-leaf nodes will be represented by directories.
1833 * sysctl(2) can automatically manage read and write requests through
1834 * the sysctl table. The data and maxlen fields of the ctl_table
1835 * struct enable minimal validation of the values being written to be
1836 * performed, and the mode field allows minimal authentication.
1838 * There must be a proc_handler routine for any terminal nodes
1839 * mirrored under /proc/sys (non-terminals are handled by a built-in
1840 * directory handler). Several default handlers are available to
1841 * cover common cases -
1843 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1844 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1845 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1847 * It is the handler's job to read the input buffer from user memory
1848 * and process it. The handler should return 0 on success.
1850 * This routine returns %NULL on a failure to register, and a pointer
1851 * to the table header on success.
1853 struct ctl_table_header *__register_sysctl_paths(
1854 struct ctl_table_root *root,
1855 struct nsproxy *namespaces,
1856 const struct ctl_path *path, struct ctl_table *table)
1858 struct ctl_table_header *header;
1859 struct ctl_table *new, **prevp;
1860 unsigned int n, npath;
1861 struct ctl_table_set *set;
1863 /* Count the path components */
1864 for (npath = 0; path[npath].procname; ++npath)
1868 * For each path component, allocate a 2-element ctl_table array.
1869 * The first array element will be filled with the sysctl entry
1870 * for this, the second will be the sentinel (procname == 0).
1872 * We allocate everything in one go so that we don't have to
1873 * worry about freeing additional memory in unregister_sysctl_table.
1875 header = kzalloc(sizeof(struct ctl_table_header) +
1876 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1877 if (!header)
1878 return NULL;
1880 new = (struct ctl_table *) (header + 1);
1882 /* Now connect the dots */
1883 prevp = &header->ctl_table;
1884 for (n = 0; n < npath; ++n, ++path) {
1885 /* Copy the procname */
1886 new->procname = path->procname;
1887 new->mode = 0555;
1889 *prevp = new;
1890 prevp = &new->child;
1892 new += 2;
1894 *prevp = table;
1895 header->ctl_table_arg = table;
1897 INIT_LIST_HEAD(&header->ctl_entry);
1898 header->used = 0;
1899 header->unregistering = NULL;
1900 header->root = root;
1901 sysctl_set_parent(NULL, header->ctl_table);
1902 header->count = 1;
1903 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1904 if (sysctl_check_table(namespaces, header->ctl_table)) {
1905 kfree(header);
1906 return NULL;
1908 #endif
1909 spin_lock(&sysctl_lock);
1910 header->set = lookup_header_set(root, namespaces);
1911 header->attached_by = header->ctl_table;
1912 header->attached_to = root_table;
1913 header->parent = &root_table_header;
1914 for (set = header->set; set; set = set->parent) {
1915 struct ctl_table_header *p;
1916 list_for_each_entry(p, &set->list, ctl_entry) {
1917 if (p->unregistering)
1918 continue;
1919 try_attach(p, header);
1922 header->parent->count++;
1923 list_add_tail(&header->ctl_entry, &header->set->list);
1924 spin_unlock(&sysctl_lock);
1926 return header;
1930 * register_sysctl_table_path - register a sysctl table hierarchy
1931 * @path: The path to the directory the sysctl table is in.
1932 * @table: the top-level table structure
1934 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1935 * array. A completely 0 filled entry terminates the table.
1937 * See __register_sysctl_paths for more details.
1939 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1940 struct ctl_table *table)
1942 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1943 path, table);
1947 * register_sysctl_table - register a sysctl table hierarchy
1948 * @table: the top-level table structure
1950 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1951 * array. A completely 0 filled entry terminates the table.
1953 * See register_sysctl_paths for more details.
1955 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
1957 static const struct ctl_path null_path[] = { {} };
1959 return register_sysctl_paths(null_path, table);
1963 * unregister_sysctl_table - unregister a sysctl table hierarchy
1964 * @header: the header returned from register_sysctl_table
1966 * Unregisters the sysctl table and all children. proc entries may not
1967 * actually be removed until they are no longer used by anyone.
1969 void unregister_sysctl_table(struct ctl_table_header * header)
1971 might_sleep();
1973 if (header == NULL)
1974 return;
1976 spin_lock(&sysctl_lock);
1977 start_unregistering(header);
1978 if (!--header->parent->count) {
1979 WARN_ON(1);
1980 kfree_rcu(header->parent, rcu);
1982 if (!--header->count)
1983 kfree_rcu(header, rcu);
1984 spin_unlock(&sysctl_lock);
1987 int sysctl_is_seen(struct ctl_table_header *p)
1989 struct ctl_table_set *set = p->set;
1990 int res;
1991 spin_lock(&sysctl_lock);
1992 if (p->unregistering)
1993 res = 0;
1994 else if (!set->is_seen)
1995 res = 1;
1996 else
1997 res = set->is_seen(set);
1998 spin_unlock(&sysctl_lock);
1999 return res;
2002 void setup_sysctl_set(struct ctl_table_set *p,
2003 struct ctl_table_set *parent,
2004 int (*is_seen)(struct ctl_table_set *))
2006 INIT_LIST_HEAD(&p->list);
2007 p->parent = parent ? parent : &sysctl_table_root.default_set;
2008 p->is_seen = is_seen;
2011 #else /* !CONFIG_SYSCTL */
2012 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2014 return NULL;
2017 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2018 struct ctl_table *table)
2020 return NULL;
2023 void unregister_sysctl_table(struct ctl_table_header * table)
2027 void setup_sysctl_set(struct ctl_table_set *p,
2028 struct ctl_table_set *parent,
2029 int (*is_seen)(struct ctl_table_set *))
2033 void sysctl_head_put(struct ctl_table_header *head)
2037 #endif /* CONFIG_SYSCTL */
2040 * /proc/sys support
2043 #ifdef CONFIG_PROC_SYSCTL
2045 static int _proc_do_string(void* data, int maxlen, int write,
2046 void __user *buffer,
2047 size_t *lenp, loff_t *ppos)
2049 size_t len;
2050 char __user *p;
2051 char c;
2053 if (!data || !maxlen || !*lenp) {
2054 *lenp = 0;
2055 return 0;
2058 if (write) {
2059 len = 0;
2060 p = buffer;
2061 while (len < *lenp) {
2062 if (get_user(c, p++))
2063 return -EFAULT;
2064 if (c == 0 || c == '\n')
2065 break;
2066 len++;
2068 if (len >= maxlen)
2069 len = maxlen-1;
2070 if(copy_from_user(data, buffer, len))
2071 return -EFAULT;
2072 ((char *) data)[len] = 0;
2073 *ppos += *lenp;
2074 } else {
2075 len = strlen(data);
2076 if (len > maxlen)
2077 len = maxlen;
2079 if (*ppos > len) {
2080 *lenp = 0;
2081 return 0;
2084 data += *ppos;
2085 len -= *ppos;
2087 if (len > *lenp)
2088 len = *lenp;
2089 if (len)
2090 if(copy_to_user(buffer, data, len))
2091 return -EFAULT;
2092 if (len < *lenp) {
2093 if(put_user('\n', ((char __user *) buffer) + len))
2094 return -EFAULT;
2095 len++;
2097 *lenp = len;
2098 *ppos += len;
2100 return 0;
2104 * proc_dostring - read a string sysctl
2105 * @table: the sysctl table
2106 * @write: %TRUE if this is a write to the sysctl file
2107 * @buffer: the user buffer
2108 * @lenp: the size of the user buffer
2109 * @ppos: file position
2111 * Reads/writes a string from/to the user buffer. If the kernel
2112 * buffer provided is not large enough to hold the string, the
2113 * string is truncated. The copied string is %NULL-terminated.
2114 * If the string is being read by the user process, it is copied
2115 * and a newline '\n' is added. It is truncated if the buffer is
2116 * not large enough.
2118 * Returns 0 on success.
2120 int proc_dostring(struct ctl_table *table, int write,
2121 void __user *buffer, size_t *lenp, loff_t *ppos)
2123 return _proc_do_string(table->data, table->maxlen, write,
2124 buffer, lenp, ppos);
2127 static size_t proc_skip_spaces(char **buf)
2129 size_t ret;
2130 char *tmp = skip_spaces(*buf);
2131 ret = tmp - *buf;
2132 *buf = tmp;
2133 return ret;
2136 static void proc_skip_char(char **buf, size_t *size, const char v)
2138 while (*size) {
2139 if (**buf != v)
2140 break;
2141 (*size)--;
2142 (*buf)++;
2146 #define TMPBUFLEN 22
2148 * proc_get_long - reads an ASCII formatted integer from a user buffer
2150 * @buf: a kernel buffer
2151 * @size: size of the kernel buffer
2152 * @val: this is where the number will be stored
2153 * @neg: set to %TRUE if number is negative
2154 * @perm_tr: a vector which contains the allowed trailers
2155 * @perm_tr_len: size of the perm_tr vector
2156 * @tr: pointer to store the trailer character
2158 * In case of success %0 is returned and @buf and @size are updated with
2159 * the amount of bytes read. If @tr is non-NULL and a trailing
2160 * character exists (size is non-zero after returning from this
2161 * function), @tr is updated with the trailing character.
2163 static int proc_get_long(char **buf, size_t *size,
2164 unsigned long *val, bool *neg,
2165 const char *perm_tr, unsigned perm_tr_len, char *tr)
2167 int len;
2168 char *p, tmp[TMPBUFLEN];
2170 if (!*size)
2171 return -EINVAL;
2173 len = *size;
2174 if (len > TMPBUFLEN - 1)
2175 len = TMPBUFLEN - 1;
2177 memcpy(tmp, *buf, len);
2179 tmp[len] = 0;
2180 p = tmp;
2181 if (*p == '-' && *size > 1) {
2182 *neg = true;
2183 p++;
2184 } else
2185 *neg = false;
2186 if (!isdigit(*p))
2187 return -EINVAL;
2189 *val = simple_strtoul(p, &p, 0);
2191 len = p - tmp;
2193 /* We don't know if the next char is whitespace thus we may accept
2194 * invalid integers (e.g. 1234...a) or two integers instead of one
2195 * (e.g. 123...1). So lets not allow such large numbers. */
2196 if (len == TMPBUFLEN - 1)
2197 return -EINVAL;
2199 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2200 return -EINVAL;
2202 if (tr && (len < *size))
2203 *tr = *p;
2205 *buf += len;
2206 *size -= len;
2208 return 0;
2212 * proc_put_long - converts an integer to a decimal ASCII formatted string
2214 * @buf: the user buffer
2215 * @size: the size of the user buffer
2216 * @val: the integer to be converted
2217 * @neg: sign of the number, %TRUE for negative
2219 * In case of success %0 is returned and @buf and @size are updated with
2220 * the amount of bytes written.
2222 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2223 bool neg)
2225 int len;
2226 char tmp[TMPBUFLEN], *p = tmp;
2228 sprintf(p, "%s%lu", neg ? "-" : "", val);
2229 len = strlen(tmp);
2230 if (len > *size)
2231 len = *size;
2232 if (copy_to_user(*buf, tmp, len))
2233 return -EFAULT;
2234 *size -= len;
2235 *buf += len;
2236 return 0;
2238 #undef TMPBUFLEN
2240 static int proc_put_char(void __user **buf, size_t *size, char c)
2242 if (*size) {
2243 char __user **buffer = (char __user **)buf;
2244 if (put_user(c, *buffer))
2245 return -EFAULT;
2246 (*size)--, (*buffer)++;
2247 *buf = *buffer;
2249 return 0;
2252 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2253 int *valp,
2254 int write, void *data)
2256 if (write) {
2257 *valp = *negp ? -*lvalp : *lvalp;
2258 } else {
2259 int val = *valp;
2260 if (val < 0) {
2261 *negp = true;
2262 *lvalp = (unsigned long)-val;
2263 } else {
2264 *negp = false;
2265 *lvalp = (unsigned long)val;
2268 return 0;
2271 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2273 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2274 int write, void __user *buffer,
2275 size_t *lenp, loff_t *ppos,
2276 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2277 int write, void *data),
2278 void *data)
2280 int *i, vleft, first = 1, err = 0;
2281 unsigned long page = 0;
2282 size_t left;
2283 char *kbuf;
2285 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2286 *lenp = 0;
2287 return 0;
2290 i = (int *) tbl_data;
2291 vleft = table->maxlen / sizeof(*i);
2292 left = *lenp;
2294 if (!conv)
2295 conv = do_proc_dointvec_conv;
2297 if (write) {
2298 if (left > PAGE_SIZE - 1)
2299 left = PAGE_SIZE - 1;
2300 page = __get_free_page(GFP_TEMPORARY);
2301 kbuf = (char *) page;
2302 if (!kbuf)
2303 return -ENOMEM;
2304 if (copy_from_user(kbuf, buffer, left)) {
2305 err = -EFAULT;
2306 goto free;
2308 kbuf[left] = 0;
2311 for (; left && vleft--; i++, first=0) {
2312 unsigned long lval;
2313 bool neg;
2315 if (write) {
2316 left -= proc_skip_spaces(&kbuf);
2318 if (!left)
2319 break;
2320 err = proc_get_long(&kbuf, &left, &lval, &neg,
2321 proc_wspace_sep,
2322 sizeof(proc_wspace_sep), NULL);
2323 if (err)
2324 break;
2325 if (conv(&neg, &lval, i, 1, data)) {
2326 err = -EINVAL;
2327 break;
2329 } else {
2330 if (conv(&neg, &lval, i, 0, data)) {
2331 err = -EINVAL;
2332 break;
2334 if (!first)
2335 err = proc_put_char(&buffer, &left, '\t');
2336 if (err)
2337 break;
2338 err = proc_put_long(&buffer, &left, lval, neg);
2339 if (err)
2340 break;
2344 if (!write && !first && left && !err)
2345 err = proc_put_char(&buffer, &left, '\n');
2346 if (write && !err && left)
2347 left -= proc_skip_spaces(&kbuf);
2348 free:
2349 if (write) {
2350 free_page(page);
2351 if (first)
2352 return err ? : -EINVAL;
2354 *lenp -= left;
2355 *ppos += *lenp;
2356 return err;
2359 static int do_proc_dointvec(struct ctl_table *table, int write,
2360 void __user *buffer, size_t *lenp, loff_t *ppos,
2361 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2362 int write, void *data),
2363 void *data)
2365 return __do_proc_dointvec(table->data, table, write,
2366 buffer, lenp, ppos, conv, data);
2370 * proc_dointvec - read a vector of integers
2371 * @table: the sysctl table
2372 * @write: %TRUE if this is a write to the sysctl file
2373 * @buffer: the user buffer
2374 * @lenp: the size of the user buffer
2375 * @ppos: file position
2377 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2378 * values from/to the user buffer, treated as an ASCII string.
2380 * Returns 0 on success.
2382 int proc_dointvec(struct ctl_table *table, int write,
2383 void __user *buffer, size_t *lenp, loff_t *ppos)
2385 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2386 NULL,NULL);
2390 * Taint values can only be increased
2391 * This means we can safely use a temporary.
2393 static int proc_taint(struct ctl_table *table, int write,
2394 void __user *buffer, size_t *lenp, loff_t *ppos)
2396 struct ctl_table t;
2397 unsigned long tmptaint = get_taint();
2398 int err;
2400 if (write && !capable(CAP_SYS_ADMIN))
2401 return -EPERM;
2403 t = *table;
2404 t.data = &tmptaint;
2405 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2406 if (err < 0)
2407 return err;
2409 if (write) {
2411 * Poor man's atomic or. Not worth adding a primitive
2412 * to everyone's atomic.h for this
2414 int i;
2415 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2416 if ((tmptaint >> i) & 1)
2417 add_taint(i);
2421 return err;
2424 #ifdef CONFIG_PRINTK
2425 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2426 void __user *buffer, size_t *lenp, loff_t *ppos)
2428 if (write && !capable(CAP_SYS_ADMIN))
2429 return -EPERM;
2431 return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2433 #endif
2435 struct do_proc_dointvec_minmax_conv_param {
2436 int *min;
2437 int *max;
2440 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2441 int *valp,
2442 int write, void *data)
2444 struct do_proc_dointvec_minmax_conv_param *param = data;
2445 if (write) {
2446 int val = *negp ? -*lvalp : *lvalp;
2447 if ((param->min && *param->min > val) ||
2448 (param->max && *param->max < val))
2449 return -EINVAL;
2450 *valp = val;
2451 } else {
2452 int val = *valp;
2453 if (val < 0) {
2454 *negp = true;
2455 *lvalp = (unsigned long)-val;
2456 } else {
2457 *negp = false;
2458 *lvalp = (unsigned long)val;
2461 return 0;
2465 * proc_dointvec_minmax - read a vector of integers with min/max values
2466 * @table: the sysctl table
2467 * @write: %TRUE if this is a write to the sysctl file
2468 * @buffer: the user buffer
2469 * @lenp: the size of the user buffer
2470 * @ppos: file position
2472 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2473 * values from/to the user buffer, treated as an ASCII string.
2475 * This routine will ensure the values are within the range specified by
2476 * table->extra1 (min) and table->extra2 (max).
2478 * Returns 0 on success.
2480 int proc_dointvec_minmax(struct ctl_table *table, int write,
2481 void __user *buffer, size_t *lenp, loff_t *ppos)
2483 struct do_proc_dointvec_minmax_conv_param param = {
2484 .min = (int *) table->extra1,
2485 .max = (int *) table->extra2,
2487 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2488 do_proc_dointvec_minmax_conv, &param);
2491 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2492 void __user *buffer,
2493 size_t *lenp, loff_t *ppos,
2494 unsigned long convmul,
2495 unsigned long convdiv)
2497 unsigned long *i, *min, *max;
2498 int vleft, first = 1, err = 0;
2499 unsigned long page = 0;
2500 size_t left;
2501 char *kbuf;
2503 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2504 *lenp = 0;
2505 return 0;
2508 i = (unsigned long *) data;
2509 min = (unsigned long *) table->extra1;
2510 max = (unsigned long *) table->extra2;
2511 vleft = table->maxlen / sizeof(unsigned long);
2512 left = *lenp;
2514 if (write) {
2515 if (left > PAGE_SIZE - 1)
2516 left = PAGE_SIZE - 1;
2517 page = __get_free_page(GFP_TEMPORARY);
2518 kbuf = (char *) page;
2519 if (!kbuf)
2520 return -ENOMEM;
2521 if (copy_from_user(kbuf, buffer, left)) {
2522 err = -EFAULT;
2523 goto free;
2525 kbuf[left] = 0;
2528 for (; left && vleft--; i++, first = 0) {
2529 unsigned long val;
2531 if (write) {
2532 bool neg;
2534 left -= proc_skip_spaces(&kbuf);
2536 err = proc_get_long(&kbuf, &left, &val, &neg,
2537 proc_wspace_sep,
2538 sizeof(proc_wspace_sep), NULL);
2539 if (err)
2540 break;
2541 if (neg)
2542 continue;
2543 if ((min && val < *min) || (max && val > *max))
2544 continue;
2545 *i = val;
2546 } else {
2547 val = convdiv * (*i) / convmul;
2548 if (!first)
2549 err = proc_put_char(&buffer, &left, '\t');
2550 err = proc_put_long(&buffer, &left, val, false);
2551 if (err)
2552 break;
2556 if (!write && !first && left && !err)
2557 err = proc_put_char(&buffer, &left, '\n');
2558 if (write && !err)
2559 left -= proc_skip_spaces(&kbuf);
2560 free:
2561 if (write) {
2562 free_page(page);
2563 if (first)
2564 return err ? : -EINVAL;
2566 *lenp -= left;
2567 *ppos += *lenp;
2568 return err;
2571 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2572 void __user *buffer,
2573 size_t *lenp, loff_t *ppos,
2574 unsigned long convmul,
2575 unsigned long convdiv)
2577 return __do_proc_doulongvec_minmax(table->data, table, write,
2578 buffer, lenp, ppos, convmul, convdiv);
2582 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2583 * @table: the sysctl table
2584 * @write: %TRUE if this is a write to the sysctl file
2585 * @buffer: the user buffer
2586 * @lenp: the size of the user buffer
2587 * @ppos: file position
2589 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2590 * values from/to the user buffer, treated as an ASCII string.
2592 * This routine will ensure the values are within the range specified by
2593 * table->extra1 (min) and table->extra2 (max).
2595 * Returns 0 on success.
2597 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2598 void __user *buffer, size_t *lenp, loff_t *ppos)
2600 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2604 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2605 * @table: the sysctl table
2606 * @write: %TRUE if this is a write to the sysctl file
2607 * @buffer: the user buffer
2608 * @lenp: the size of the user buffer
2609 * @ppos: file position
2611 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2612 * values from/to the user buffer, treated as an ASCII string. The values
2613 * are treated as milliseconds, and converted to jiffies when they are stored.
2615 * This routine will ensure the values are within the range specified by
2616 * table->extra1 (min) and table->extra2 (max).
2618 * Returns 0 on success.
2620 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2621 void __user *buffer,
2622 size_t *lenp, loff_t *ppos)
2624 return do_proc_doulongvec_minmax(table, write, buffer,
2625 lenp, ppos, HZ, 1000l);
2629 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2630 int *valp,
2631 int write, void *data)
2633 if (write) {
2634 if (*lvalp > LONG_MAX / HZ)
2635 return 1;
2636 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2637 } else {
2638 int val = *valp;
2639 unsigned long lval;
2640 if (val < 0) {
2641 *negp = true;
2642 lval = (unsigned long)-val;
2643 } else {
2644 *negp = false;
2645 lval = (unsigned long)val;
2647 *lvalp = lval / HZ;
2649 return 0;
2652 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2653 int *valp,
2654 int write, void *data)
2656 if (write) {
2657 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2658 return 1;
2659 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2660 } else {
2661 int val = *valp;
2662 unsigned long lval;
2663 if (val < 0) {
2664 *negp = true;
2665 lval = (unsigned long)-val;
2666 } else {
2667 *negp = false;
2668 lval = (unsigned long)val;
2670 *lvalp = jiffies_to_clock_t(lval);
2672 return 0;
2675 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2676 int *valp,
2677 int write, void *data)
2679 if (write) {
2680 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2681 } else {
2682 int val = *valp;
2683 unsigned long lval;
2684 if (val < 0) {
2685 *negp = true;
2686 lval = (unsigned long)-val;
2687 } else {
2688 *negp = false;
2689 lval = (unsigned long)val;
2691 *lvalp = jiffies_to_msecs(lval);
2693 return 0;
2697 * proc_dointvec_jiffies - read a vector of integers as seconds
2698 * @table: the sysctl table
2699 * @write: %TRUE if this is a write to the sysctl file
2700 * @buffer: the user buffer
2701 * @lenp: the size of the user buffer
2702 * @ppos: file position
2704 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2705 * values from/to the user buffer, treated as an ASCII string.
2706 * The values read are assumed to be in seconds, and are converted into
2707 * jiffies.
2709 * Returns 0 on success.
2711 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2712 void __user *buffer, size_t *lenp, loff_t *ppos)
2714 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2715 do_proc_dointvec_jiffies_conv,NULL);
2719 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2720 * @table: the sysctl table
2721 * @write: %TRUE if this is a write to the sysctl file
2722 * @buffer: the user buffer
2723 * @lenp: the size of the user buffer
2724 * @ppos: pointer to the file position
2726 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2727 * values from/to the user buffer, treated as an ASCII string.
2728 * The values read are assumed to be in 1/USER_HZ seconds, and
2729 * are converted into jiffies.
2731 * Returns 0 on success.
2733 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2734 void __user *buffer, size_t *lenp, loff_t *ppos)
2736 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2737 do_proc_dointvec_userhz_jiffies_conv,NULL);
2741 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2742 * @table: the sysctl table
2743 * @write: %TRUE if this is a write to the sysctl file
2744 * @buffer: the user buffer
2745 * @lenp: the size of the user buffer
2746 * @ppos: file position
2747 * @ppos: the current position in the file
2749 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2750 * values from/to the user buffer, treated as an ASCII string.
2751 * The values read are assumed to be in 1/1000 seconds, and
2752 * are converted into jiffies.
2754 * Returns 0 on success.
2756 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2757 void __user *buffer, size_t *lenp, loff_t *ppos)
2759 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2760 do_proc_dointvec_ms_jiffies_conv, NULL);
2763 static int proc_do_cad_pid(struct ctl_table *table, int write,
2764 void __user *buffer, size_t *lenp, loff_t *ppos)
2766 struct pid *new_pid;
2767 pid_t tmp;
2768 int r;
2770 tmp = pid_vnr(cad_pid);
2772 r = __do_proc_dointvec(&tmp, table, write, buffer,
2773 lenp, ppos, NULL, NULL);
2774 if (r || !write)
2775 return r;
2777 new_pid = find_get_pid(tmp);
2778 if (!new_pid)
2779 return -ESRCH;
2781 put_pid(xchg(&cad_pid, new_pid));
2782 return 0;
2786 * proc_do_large_bitmap - read/write from/to a large bitmap
2787 * @table: the sysctl table
2788 * @write: %TRUE if this is a write to the sysctl file
2789 * @buffer: the user buffer
2790 * @lenp: the size of the user buffer
2791 * @ppos: file position
2793 * The bitmap is stored at table->data and the bitmap length (in bits)
2794 * in table->maxlen.
2796 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2797 * large bitmaps may be represented in a compact manner. Writing into
2798 * the file will clear the bitmap then update it with the given input.
2800 * Returns 0 on success.
2802 int proc_do_large_bitmap(struct ctl_table *table, int write,
2803 void __user *buffer, size_t *lenp, loff_t *ppos)
2805 int err = 0;
2806 bool first = 1;
2807 size_t left = *lenp;
2808 unsigned long bitmap_len = table->maxlen;
2809 unsigned long *bitmap = (unsigned long *) table->data;
2810 unsigned long *tmp_bitmap = NULL;
2811 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2813 if (!bitmap_len || !left || (*ppos && !write)) {
2814 *lenp = 0;
2815 return 0;
2818 if (write) {
2819 unsigned long page = 0;
2820 char *kbuf;
2822 if (left > PAGE_SIZE - 1)
2823 left = PAGE_SIZE - 1;
2825 page = __get_free_page(GFP_TEMPORARY);
2826 kbuf = (char *) page;
2827 if (!kbuf)
2828 return -ENOMEM;
2829 if (copy_from_user(kbuf, buffer, left)) {
2830 free_page(page);
2831 return -EFAULT;
2833 kbuf[left] = 0;
2835 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2836 GFP_KERNEL);
2837 if (!tmp_bitmap) {
2838 free_page(page);
2839 return -ENOMEM;
2841 proc_skip_char(&kbuf, &left, '\n');
2842 while (!err && left) {
2843 unsigned long val_a, val_b;
2844 bool neg;
2846 err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2847 sizeof(tr_a), &c);
2848 if (err)
2849 break;
2850 if (val_a >= bitmap_len || neg) {
2851 err = -EINVAL;
2852 break;
2855 val_b = val_a;
2856 if (left) {
2857 kbuf++;
2858 left--;
2861 if (c == '-') {
2862 err = proc_get_long(&kbuf, &left, &val_b,
2863 &neg, tr_b, sizeof(tr_b),
2864 &c);
2865 if (err)
2866 break;
2867 if (val_b >= bitmap_len || neg ||
2868 val_a > val_b) {
2869 err = -EINVAL;
2870 break;
2872 if (left) {
2873 kbuf++;
2874 left--;
2878 while (val_a <= val_b)
2879 set_bit(val_a++, tmp_bitmap);
2881 first = 0;
2882 proc_skip_char(&kbuf, &left, '\n');
2884 free_page(page);
2885 } else {
2886 unsigned long bit_a, bit_b = 0;
2888 while (left) {
2889 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2890 if (bit_a >= bitmap_len)
2891 break;
2892 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2893 bit_a + 1) - 1;
2895 if (!first) {
2896 err = proc_put_char(&buffer, &left, ',');
2897 if (err)
2898 break;
2900 err = proc_put_long(&buffer, &left, bit_a, false);
2901 if (err)
2902 break;
2903 if (bit_a != bit_b) {
2904 err = proc_put_char(&buffer, &left, '-');
2905 if (err)
2906 break;
2907 err = proc_put_long(&buffer, &left, bit_b, false);
2908 if (err)
2909 break;
2912 first = 0; bit_b++;
2914 if (!err)
2915 err = proc_put_char(&buffer, &left, '\n');
2918 if (!err) {
2919 if (write) {
2920 if (*ppos)
2921 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2922 else
2923 memcpy(bitmap, tmp_bitmap,
2924 BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long));
2926 kfree(tmp_bitmap);
2927 *lenp -= left;
2928 *ppos += *lenp;
2929 return 0;
2930 } else {
2931 kfree(tmp_bitmap);
2932 return err;
2936 #else /* CONFIG_PROC_SYSCTL */
2938 int proc_dostring(struct ctl_table *table, int write,
2939 void __user *buffer, size_t *lenp, loff_t *ppos)
2941 return -ENOSYS;
2944 int proc_dointvec(struct ctl_table *table, int write,
2945 void __user *buffer, size_t *lenp, loff_t *ppos)
2947 return -ENOSYS;
2950 int proc_dointvec_minmax(struct ctl_table *table, int write,
2951 void __user *buffer, size_t *lenp, loff_t *ppos)
2953 return -ENOSYS;
2956 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2957 void __user *buffer, size_t *lenp, loff_t *ppos)
2959 return -ENOSYS;
2962 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2963 void __user *buffer, size_t *lenp, loff_t *ppos)
2965 return -ENOSYS;
2968 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2969 void __user *buffer, size_t *lenp, loff_t *ppos)
2971 return -ENOSYS;
2974 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2975 void __user *buffer, size_t *lenp, loff_t *ppos)
2977 return -ENOSYS;
2980 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2981 void __user *buffer,
2982 size_t *lenp, loff_t *ppos)
2984 return -ENOSYS;
2988 #endif /* CONFIG_PROC_SYSCTL */
2991 * No sense putting this after each symbol definition, twice,
2992 * exception granted :-)
2994 EXPORT_SYMBOL(proc_dointvec);
2995 EXPORT_SYMBOL(proc_dointvec_jiffies);
2996 EXPORT_SYMBOL(proc_dointvec_minmax);
2997 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2998 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2999 EXPORT_SYMBOL(proc_dostring);
3000 EXPORT_SYMBOL(proc_doulongvec_minmax);
3001 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3002 EXPORT_SYMBOL(register_sysctl_table);
3003 EXPORT_SYMBOL(register_sysctl_paths);
3004 EXPORT_SYMBOL(unregister_sysctl_table);