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
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
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>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/security.h>
28 #include <linux/ctype.h>
29 #include <linux/kmemcheck.h>
30 #include <linux/smp_lock.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/initrd.h>
41 #include <linux/key.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/vmstat.h>
47 #include <linux/nfs_fs.h>
48 #include <linux/acpi.h>
49 #include <linux/reboot.h>
50 #include <linux/ftrace.h>
51 #include <linux/slow-work.h>
52 #include <linux/perf_event.h>
54 #include <asm/uaccess.h>
55 #include <asm/processor.h>
59 #include <asm/stacktrace.h>
63 static int deprecated_sysctl_warning(struct __sysctl_args *args);
65 #if defined(CONFIG_SYSCTL)
67 /* External variables not in a header file. */
69 extern int print_fatal_signals;
70 extern int sysctl_overcommit_memory;
71 extern int sysctl_overcommit_ratio;
72 extern int sysctl_panic_on_oom;
73 extern int sysctl_oom_kill_allocating_task;
74 extern int sysctl_oom_dump_tasks;
75 extern int max_threads;
76 extern int core_uses_pid;
77 extern int suid_dumpable;
78 extern char core_pattern[];
79 extern unsigned int core_pipe_limit;
81 extern int min_free_kbytes;
82 extern int pid_max_min, pid_max_max;
83 extern int sysctl_drop_caches;
84 extern int percpu_pagelist_fraction;
85 extern int compat_log;
86 extern int latencytop_enabled;
87 extern int sysctl_nr_open_min, sysctl_nr_open_max;
89 extern int sysctl_nr_trim_pages;
91 #ifdef CONFIG_RCU_TORTURE_TEST
92 extern int rcutorture_runnable;
93 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
95 extern int blk_iopoll_enabled;
98 /* Constants used for minimum and maximum */
99 #ifdef CONFIG_DETECT_SOFTLOCKUP
100 static int sixty = 60;
101 static int neg_one = -1;
105 static int __maybe_unused one = 1;
106 static int __maybe_unused two = 2;
107 static unsigned long one_ul = 1;
108 static int one_hundred = 100;
110 static int ten_thousand = 10000;
113 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
114 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
116 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
117 static int maxolduid = 65535;
118 static int minolduid;
119 static int min_percpu_pagelist_fract = 8;
121 static int ngroups_max = NGROUPS_MAX;
123 #ifdef CONFIG_MODULES
124 extern char modprobe_path[];
125 extern int modules_disabled;
127 #ifdef CONFIG_CHR_DEV_SG
128 extern int sg_big_buff;
132 #include <asm/system.h>
135 #ifdef CONFIG_SPARC64
136 extern int sysctl_tsb_ratio;
140 extern int pwrsw_enabled;
141 extern int unaligned_enabled;
145 #ifdef CONFIG_MATHEMU
146 extern int sysctl_ieee_emulation_warnings;
148 extern int sysctl_userprocess_debug;
149 extern int spin_retry;
152 #ifdef CONFIG_BSD_PROCESS_ACCT
153 extern int acct_parm[];
157 extern int no_unaligned_warning;
158 extern int unaligned_dump_stack;
161 #ifdef CONFIG_RT_MUTEXES
162 extern int max_lock_depth;
165 #ifdef CONFIG_PROC_SYSCTL
166 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
167 void __user *buffer, size_t *lenp, loff_t *ppos);
168 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
169 void __user *buffer, size_t *lenp, loff_t *ppos);
172 static struct ctl_table root_table[];
173 static struct ctl_table_root sysctl_table_root;
174 static struct ctl_table_header root_table_header = {
176 .ctl_table = root_table,
177 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
178 .root = &sysctl_table_root,
179 .set = &sysctl_table_root.default_set,
181 static struct ctl_table_root sysctl_table_root = {
182 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
183 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
186 static struct ctl_table kern_table[];
187 static struct ctl_table vm_table[];
188 static struct ctl_table fs_table[];
189 static struct ctl_table debug_table[];
190 static struct ctl_table dev_table[];
191 extern struct ctl_table random_table[];
192 #ifdef CONFIG_INOTIFY_USER
193 extern struct ctl_table inotify_table[];
196 extern struct ctl_table epoll_table[];
199 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
200 int sysctl_legacy_va_layout;
203 extern int prove_locking;
204 extern int lock_stat;
206 /* The default sysctl tables: */
208 static struct ctl_table root_table[] = {
210 .ctl_name = CTL_KERN,
211 .procname = "kernel",
228 .ctl_name = CTL_DEBUG,
231 .child = debug_table,
240 * NOTE: do not add new entries to this table unless you have read
241 * Documentation/sysctl/ctl_unnumbered.txt
246 #ifdef CONFIG_SCHED_DEBUG
247 static int min_sched_granularity_ns = 100000; /* 100 usecs */
248 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
249 static int min_wakeup_granularity_ns; /* 0 usecs */
250 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
253 static struct ctl_table kern_table[] = {
255 .ctl_name = CTL_UNNUMBERED,
256 .procname = "sched_child_runs_first",
257 .data = &sysctl_sched_child_runs_first,
258 .maxlen = sizeof(unsigned int),
260 .proc_handler = &proc_dointvec,
262 #ifdef CONFIG_SCHED_DEBUG
264 .ctl_name = CTL_UNNUMBERED,
265 .procname = "sched_min_granularity_ns",
266 .data = &sysctl_sched_min_granularity,
267 .maxlen = sizeof(unsigned int),
269 .proc_handler = &sched_nr_latency_handler,
270 .strategy = &sysctl_intvec,
271 .extra1 = &min_sched_granularity_ns,
272 .extra2 = &max_sched_granularity_ns,
275 .ctl_name = CTL_UNNUMBERED,
276 .procname = "sched_latency_ns",
277 .data = &sysctl_sched_latency,
278 .maxlen = sizeof(unsigned int),
280 .proc_handler = &sched_nr_latency_handler,
281 .strategy = &sysctl_intvec,
282 .extra1 = &min_sched_granularity_ns,
283 .extra2 = &max_sched_granularity_ns,
286 .ctl_name = CTL_UNNUMBERED,
287 .procname = "sched_wakeup_granularity_ns",
288 .data = &sysctl_sched_wakeup_granularity,
289 .maxlen = sizeof(unsigned int),
291 .proc_handler = &proc_dointvec_minmax,
292 .strategy = &sysctl_intvec,
293 .extra1 = &min_wakeup_granularity_ns,
294 .extra2 = &max_wakeup_granularity_ns,
297 .ctl_name = CTL_UNNUMBERED,
298 .procname = "sched_shares_ratelimit",
299 .data = &sysctl_sched_shares_ratelimit,
300 .maxlen = sizeof(unsigned int),
302 .proc_handler = &proc_dointvec,
305 .ctl_name = CTL_UNNUMBERED,
306 .procname = "sched_shares_thresh",
307 .data = &sysctl_sched_shares_thresh,
308 .maxlen = sizeof(unsigned int),
310 .proc_handler = &proc_dointvec_minmax,
311 .strategy = &sysctl_intvec,
315 .ctl_name = CTL_UNNUMBERED,
316 .procname = "sched_features",
317 .data = &sysctl_sched_features,
318 .maxlen = sizeof(unsigned int),
320 .proc_handler = &proc_dointvec,
323 .ctl_name = CTL_UNNUMBERED,
324 .procname = "sched_migration_cost",
325 .data = &sysctl_sched_migration_cost,
326 .maxlen = sizeof(unsigned int),
328 .proc_handler = &proc_dointvec,
331 .ctl_name = CTL_UNNUMBERED,
332 .procname = "sched_nr_migrate",
333 .data = &sysctl_sched_nr_migrate,
334 .maxlen = sizeof(unsigned int),
336 .proc_handler = &proc_dointvec,
339 .ctl_name = CTL_UNNUMBERED,
340 .procname = "sched_time_avg",
341 .data = &sysctl_sched_time_avg,
342 .maxlen = sizeof(unsigned int),
344 .proc_handler = &proc_dointvec,
347 .ctl_name = CTL_UNNUMBERED,
348 .procname = "timer_migration",
349 .data = &sysctl_timer_migration,
350 .maxlen = sizeof(unsigned int),
352 .proc_handler = &proc_dointvec_minmax,
353 .strategy = &sysctl_intvec,
359 .ctl_name = CTL_UNNUMBERED,
360 .procname = "sched_rt_period_us",
361 .data = &sysctl_sched_rt_period,
362 .maxlen = sizeof(unsigned int),
364 .proc_handler = &sched_rt_handler,
367 .ctl_name = CTL_UNNUMBERED,
368 .procname = "sched_rt_runtime_us",
369 .data = &sysctl_sched_rt_runtime,
370 .maxlen = sizeof(int),
372 .proc_handler = &sched_rt_handler,
375 .ctl_name = CTL_UNNUMBERED,
376 .procname = "sched_compat_yield",
377 .data = &sysctl_sched_compat_yield,
378 .maxlen = sizeof(unsigned int),
380 .proc_handler = &proc_dointvec,
382 #ifdef CONFIG_PROVE_LOCKING
384 .ctl_name = CTL_UNNUMBERED,
385 .procname = "prove_locking",
386 .data = &prove_locking,
387 .maxlen = sizeof(int),
389 .proc_handler = &proc_dointvec,
392 #ifdef CONFIG_LOCK_STAT
394 .ctl_name = CTL_UNNUMBERED,
395 .procname = "lock_stat",
397 .maxlen = sizeof(int),
399 .proc_handler = &proc_dointvec,
403 .ctl_name = KERN_PANIC,
405 .data = &panic_timeout,
406 .maxlen = sizeof(int),
408 .proc_handler = &proc_dointvec,
411 .ctl_name = KERN_CORE_USES_PID,
412 .procname = "core_uses_pid",
413 .data = &core_uses_pid,
414 .maxlen = sizeof(int),
416 .proc_handler = &proc_dointvec,
419 .ctl_name = KERN_CORE_PATTERN,
420 .procname = "core_pattern",
421 .data = core_pattern,
422 .maxlen = CORENAME_MAX_SIZE,
424 .proc_handler = &proc_dostring,
425 .strategy = &sysctl_string,
428 .ctl_name = CTL_UNNUMBERED,
429 .procname = "core_pipe_limit",
430 .data = &core_pipe_limit,
431 .maxlen = sizeof(unsigned int),
433 .proc_handler = &proc_dointvec,
435 #ifdef CONFIG_PROC_SYSCTL
437 .procname = "tainted",
438 .maxlen = sizeof(long),
440 .proc_handler = &proc_taint,
443 #ifdef CONFIG_LATENCYTOP
445 .procname = "latencytop",
446 .data = &latencytop_enabled,
447 .maxlen = sizeof(int),
449 .proc_handler = &proc_dointvec,
452 #ifdef CONFIG_BLK_DEV_INITRD
454 .ctl_name = KERN_REALROOTDEV,
455 .procname = "real-root-dev",
456 .data = &real_root_dev,
457 .maxlen = sizeof(int),
459 .proc_handler = &proc_dointvec,
463 .ctl_name = CTL_UNNUMBERED,
464 .procname = "print-fatal-signals",
465 .data = &print_fatal_signals,
466 .maxlen = sizeof(int),
468 .proc_handler = &proc_dointvec,
472 .ctl_name = KERN_SPARC_REBOOT,
473 .procname = "reboot-cmd",
474 .data = reboot_command,
477 .proc_handler = &proc_dostring,
478 .strategy = &sysctl_string,
481 .ctl_name = KERN_SPARC_STOP_A,
482 .procname = "stop-a",
483 .data = &stop_a_enabled,
484 .maxlen = sizeof (int),
486 .proc_handler = &proc_dointvec,
489 .ctl_name = KERN_SPARC_SCONS_PWROFF,
490 .procname = "scons-poweroff",
491 .data = &scons_pwroff,
492 .maxlen = sizeof (int),
494 .proc_handler = &proc_dointvec,
497 #ifdef CONFIG_SPARC64
499 .ctl_name = CTL_UNNUMBERED,
500 .procname = "tsb-ratio",
501 .data = &sysctl_tsb_ratio,
502 .maxlen = sizeof (int),
504 .proc_handler = &proc_dointvec,
509 .ctl_name = KERN_HPPA_PWRSW,
510 .procname = "soft-power",
511 .data = &pwrsw_enabled,
512 .maxlen = sizeof (int),
514 .proc_handler = &proc_dointvec,
517 .ctl_name = KERN_HPPA_UNALIGNED,
518 .procname = "unaligned-trap",
519 .data = &unaligned_enabled,
520 .maxlen = sizeof (int),
522 .proc_handler = &proc_dointvec,
526 .ctl_name = KERN_CTLALTDEL,
527 .procname = "ctrl-alt-del",
529 .maxlen = sizeof(int),
531 .proc_handler = &proc_dointvec,
533 #ifdef CONFIG_FUNCTION_TRACER
535 .ctl_name = CTL_UNNUMBERED,
536 .procname = "ftrace_enabled",
537 .data = &ftrace_enabled,
538 .maxlen = sizeof(int),
540 .proc_handler = &ftrace_enable_sysctl,
543 #ifdef CONFIG_STACK_TRACER
545 .ctl_name = CTL_UNNUMBERED,
546 .procname = "stack_tracer_enabled",
547 .data = &stack_tracer_enabled,
548 .maxlen = sizeof(int),
550 .proc_handler = &stack_trace_sysctl,
553 #ifdef CONFIG_TRACING
555 .ctl_name = CTL_UNNUMBERED,
556 .procname = "ftrace_dump_on_oops",
557 .data = &ftrace_dump_on_oops,
558 .maxlen = sizeof(int),
560 .proc_handler = &proc_dointvec,
563 #ifdef CONFIG_MODULES
565 .ctl_name = KERN_MODPROBE,
566 .procname = "modprobe",
567 .data = &modprobe_path,
568 .maxlen = KMOD_PATH_LEN,
570 .proc_handler = &proc_dostring,
571 .strategy = &sysctl_string,
574 .ctl_name = CTL_UNNUMBERED,
575 .procname = "modules_disabled",
576 .data = &modules_disabled,
577 .maxlen = sizeof(int),
579 /* only handle a transition from default "0" to "1" */
580 .proc_handler = &proc_dointvec_minmax,
585 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
587 .ctl_name = KERN_HOTPLUG,
588 .procname = "hotplug",
589 .data = &uevent_helper,
590 .maxlen = UEVENT_HELPER_PATH_LEN,
592 .proc_handler = &proc_dostring,
593 .strategy = &sysctl_string,
596 #ifdef CONFIG_CHR_DEV_SG
598 .ctl_name = KERN_SG_BIG_BUFF,
599 .procname = "sg-big-buff",
600 .data = &sg_big_buff,
601 .maxlen = sizeof (int),
603 .proc_handler = &proc_dointvec,
606 #ifdef CONFIG_BSD_PROCESS_ACCT
608 .ctl_name = KERN_ACCT,
611 .maxlen = 3*sizeof(int),
613 .proc_handler = &proc_dointvec,
616 #ifdef CONFIG_MAGIC_SYSRQ
618 .ctl_name = KERN_SYSRQ,
620 .data = &__sysrq_enabled,
621 .maxlen = sizeof (int),
623 .proc_handler = &proc_dointvec,
626 #ifdef CONFIG_PROC_SYSCTL
628 .procname = "cad_pid",
630 .maxlen = sizeof (int),
632 .proc_handler = &proc_do_cad_pid,
636 .ctl_name = KERN_MAX_THREADS,
637 .procname = "threads-max",
638 .data = &max_threads,
639 .maxlen = sizeof(int),
641 .proc_handler = &proc_dointvec,
644 .ctl_name = KERN_RANDOM,
645 .procname = "random",
647 .child = random_table,
650 .ctl_name = KERN_OVERFLOWUID,
651 .procname = "overflowuid",
652 .data = &overflowuid,
653 .maxlen = sizeof(int),
655 .proc_handler = &proc_dointvec_minmax,
656 .strategy = &sysctl_intvec,
657 .extra1 = &minolduid,
658 .extra2 = &maxolduid,
661 .ctl_name = KERN_OVERFLOWGID,
662 .procname = "overflowgid",
663 .data = &overflowgid,
664 .maxlen = sizeof(int),
666 .proc_handler = &proc_dointvec_minmax,
667 .strategy = &sysctl_intvec,
668 .extra1 = &minolduid,
669 .extra2 = &maxolduid,
672 #ifdef CONFIG_MATHEMU
674 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
675 .procname = "ieee_emulation_warnings",
676 .data = &sysctl_ieee_emulation_warnings,
677 .maxlen = sizeof(int),
679 .proc_handler = &proc_dointvec,
683 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
684 .procname = "userprocess_debug",
685 .data = &sysctl_userprocess_debug,
686 .maxlen = sizeof(int),
688 .proc_handler = &proc_dointvec,
692 .ctl_name = KERN_PIDMAX,
693 .procname = "pid_max",
695 .maxlen = sizeof (int),
697 .proc_handler = &proc_dointvec_minmax,
698 .strategy = sysctl_intvec,
699 .extra1 = &pid_max_min,
700 .extra2 = &pid_max_max,
703 .ctl_name = KERN_PANIC_ON_OOPS,
704 .procname = "panic_on_oops",
705 .data = &panic_on_oops,
706 .maxlen = sizeof(int),
708 .proc_handler = &proc_dointvec,
710 #if defined CONFIG_PRINTK
712 .ctl_name = KERN_PRINTK,
713 .procname = "printk",
714 .data = &console_loglevel,
715 .maxlen = 4*sizeof(int),
717 .proc_handler = &proc_dointvec,
720 .ctl_name = KERN_PRINTK_RATELIMIT,
721 .procname = "printk_ratelimit",
722 .data = &printk_ratelimit_state.interval,
723 .maxlen = sizeof(int),
725 .proc_handler = &proc_dointvec_jiffies,
726 .strategy = &sysctl_jiffies,
729 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
730 .procname = "printk_ratelimit_burst",
731 .data = &printk_ratelimit_state.burst,
732 .maxlen = sizeof(int),
734 .proc_handler = &proc_dointvec,
737 .ctl_name = CTL_UNNUMBERED,
738 .procname = "printk_delay",
739 .data = &printk_delay_msec,
740 .maxlen = sizeof(int),
742 .proc_handler = &proc_dointvec_minmax,
743 .strategy = &sysctl_intvec,
745 .extra2 = &ten_thousand,
749 .ctl_name = KERN_NGROUPS_MAX,
750 .procname = "ngroups_max",
751 .data = &ngroups_max,
752 .maxlen = sizeof (int),
754 .proc_handler = &proc_dointvec,
756 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
758 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
759 .procname = "unknown_nmi_panic",
760 .data = &unknown_nmi_panic,
761 .maxlen = sizeof (int),
763 .proc_handler = &proc_dointvec,
766 .procname = "nmi_watchdog",
767 .data = &nmi_watchdog_enabled,
768 .maxlen = sizeof (int),
770 .proc_handler = &proc_nmi_enabled,
773 #if defined(CONFIG_X86)
775 .ctl_name = KERN_PANIC_ON_NMI,
776 .procname = "panic_on_unrecovered_nmi",
777 .data = &panic_on_unrecovered_nmi,
778 .maxlen = sizeof(int),
780 .proc_handler = &proc_dointvec,
783 .ctl_name = CTL_UNNUMBERED,
784 .procname = "panic_on_io_nmi",
785 .data = &panic_on_io_nmi,
786 .maxlen = sizeof(int),
788 .proc_handler = &proc_dointvec,
791 .ctl_name = KERN_BOOTLOADER_TYPE,
792 .procname = "bootloader_type",
793 .data = &bootloader_type,
794 .maxlen = sizeof (int),
796 .proc_handler = &proc_dointvec,
799 .ctl_name = CTL_UNNUMBERED,
800 .procname = "bootloader_version",
801 .data = &bootloader_version,
802 .maxlen = sizeof (int),
804 .proc_handler = &proc_dointvec,
807 .ctl_name = CTL_UNNUMBERED,
808 .procname = "kstack_depth_to_print",
809 .data = &kstack_depth_to_print,
810 .maxlen = sizeof(int),
812 .proc_handler = &proc_dointvec,
815 .ctl_name = CTL_UNNUMBERED,
816 .procname = "io_delay_type",
817 .data = &io_delay_type,
818 .maxlen = sizeof(int),
820 .proc_handler = &proc_dointvec,
823 #if defined(CONFIG_MMU)
825 .ctl_name = KERN_RANDOMIZE,
826 .procname = "randomize_va_space",
827 .data = &randomize_va_space,
828 .maxlen = sizeof(int),
830 .proc_handler = &proc_dointvec,
833 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
835 .ctl_name = KERN_SPIN_RETRY,
836 .procname = "spin_retry",
838 .maxlen = sizeof (int),
840 .proc_handler = &proc_dointvec,
843 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
845 .procname = "acpi_video_flags",
846 .data = &acpi_realmode_flags,
847 .maxlen = sizeof (unsigned long),
849 .proc_handler = &proc_doulongvec_minmax,
854 .ctl_name = KERN_IA64_UNALIGNED,
855 .procname = "ignore-unaligned-usertrap",
856 .data = &no_unaligned_warning,
857 .maxlen = sizeof (int),
859 .proc_handler = &proc_dointvec,
862 .ctl_name = CTL_UNNUMBERED,
863 .procname = "unaligned-dump-stack",
864 .data = &unaligned_dump_stack,
865 .maxlen = sizeof (int),
867 .proc_handler = &proc_dointvec,
870 #ifdef CONFIG_DETECT_SOFTLOCKUP
872 .ctl_name = CTL_UNNUMBERED,
873 .procname = "softlockup_panic",
874 .data = &softlockup_panic,
875 .maxlen = sizeof(int),
877 .proc_handler = &proc_dointvec_minmax,
878 .strategy = &sysctl_intvec,
883 .ctl_name = CTL_UNNUMBERED,
884 .procname = "softlockup_thresh",
885 .data = &softlockup_thresh,
886 .maxlen = sizeof(int),
888 .proc_handler = &proc_dosoftlockup_thresh,
889 .strategy = &sysctl_intvec,
894 #ifdef CONFIG_DETECT_HUNG_TASK
896 .ctl_name = CTL_UNNUMBERED,
897 .procname = "hung_task_panic",
898 .data = &sysctl_hung_task_panic,
899 .maxlen = sizeof(int),
901 .proc_handler = &proc_dointvec_minmax,
902 .strategy = &sysctl_intvec,
907 .ctl_name = CTL_UNNUMBERED,
908 .procname = "hung_task_check_count",
909 .data = &sysctl_hung_task_check_count,
910 .maxlen = sizeof(unsigned long),
912 .proc_handler = &proc_doulongvec_minmax,
913 .strategy = &sysctl_intvec,
916 .ctl_name = CTL_UNNUMBERED,
917 .procname = "hung_task_timeout_secs",
918 .data = &sysctl_hung_task_timeout_secs,
919 .maxlen = sizeof(unsigned long),
921 .proc_handler = &proc_dohung_task_timeout_secs,
922 .strategy = &sysctl_intvec,
925 .ctl_name = CTL_UNNUMBERED,
926 .procname = "hung_task_warnings",
927 .data = &sysctl_hung_task_warnings,
928 .maxlen = sizeof(unsigned long),
930 .proc_handler = &proc_doulongvec_minmax,
931 .strategy = &sysctl_intvec,
936 .ctl_name = KERN_COMPAT_LOG,
937 .procname = "compat-log",
939 .maxlen = sizeof (int),
941 .proc_handler = &proc_dointvec,
944 #ifdef CONFIG_RT_MUTEXES
946 .ctl_name = KERN_MAX_LOCK_DEPTH,
947 .procname = "max_lock_depth",
948 .data = &max_lock_depth,
949 .maxlen = sizeof(int),
951 .proc_handler = &proc_dointvec,
955 .ctl_name = CTL_UNNUMBERED,
956 .procname = "poweroff_cmd",
957 .data = &poweroff_cmd,
958 .maxlen = POWEROFF_CMD_PATH_LEN,
960 .proc_handler = &proc_dostring,
961 .strategy = &sysctl_string,
965 .ctl_name = CTL_UNNUMBERED,
968 .child = key_sysctls,
971 #ifdef CONFIG_RCU_TORTURE_TEST
973 .ctl_name = CTL_UNNUMBERED,
974 .procname = "rcutorture_runnable",
975 .data = &rcutorture_runnable,
976 .maxlen = sizeof(int),
978 .proc_handler = &proc_dointvec,
981 #ifdef CONFIG_SLOW_WORK
983 .ctl_name = CTL_UNNUMBERED,
984 .procname = "slow-work",
986 .child = slow_work_sysctls,
989 #ifdef CONFIG_PERF_EVENTS
991 .ctl_name = CTL_UNNUMBERED,
992 .procname = "perf_event_paranoid",
993 .data = &sysctl_perf_event_paranoid,
994 .maxlen = sizeof(sysctl_perf_event_paranoid),
996 .proc_handler = &proc_dointvec,
999 .ctl_name = CTL_UNNUMBERED,
1000 .procname = "perf_event_mlock_kb",
1001 .data = &sysctl_perf_event_mlock,
1002 .maxlen = sizeof(sysctl_perf_event_mlock),
1004 .proc_handler = &proc_dointvec,
1007 .ctl_name = CTL_UNNUMBERED,
1008 .procname = "perf_event_max_sample_rate",
1009 .data = &sysctl_perf_event_sample_rate,
1010 .maxlen = sizeof(sysctl_perf_event_sample_rate),
1012 .proc_handler = &proc_dointvec,
1015 #ifdef CONFIG_KMEMCHECK
1017 .ctl_name = CTL_UNNUMBERED,
1018 .procname = "kmemcheck",
1019 .data = &kmemcheck_enabled,
1020 .maxlen = sizeof(int),
1022 .proc_handler = &proc_dointvec,
1027 .ctl_name = CTL_UNNUMBERED,
1028 .procname = "blk_iopoll",
1029 .data = &blk_iopoll_enabled,
1030 .maxlen = sizeof(int),
1032 .proc_handler = &proc_dointvec,
1036 * NOTE: do not add new entries to this table unless you have read
1037 * Documentation/sysctl/ctl_unnumbered.txt
1042 static struct ctl_table vm_table[] = {
1044 .ctl_name = VM_OVERCOMMIT_MEMORY,
1045 .procname = "overcommit_memory",
1046 .data = &sysctl_overcommit_memory,
1047 .maxlen = sizeof(sysctl_overcommit_memory),
1049 .proc_handler = &proc_dointvec,
1052 .ctl_name = VM_PANIC_ON_OOM,
1053 .procname = "panic_on_oom",
1054 .data = &sysctl_panic_on_oom,
1055 .maxlen = sizeof(sysctl_panic_on_oom),
1057 .proc_handler = &proc_dointvec,
1060 .ctl_name = CTL_UNNUMBERED,
1061 .procname = "oom_kill_allocating_task",
1062 .data = &sysctl_oom_kill_allocating_task,
1063 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1065 .proc_handler = &proc_dointvec,
1068 .ctl_name = CTL_UNNUMBERED,
1069 .procname = "oom_dump_tasks",
1070 .data = &sysctl_oom_dump_tasks,
1071 .maxlen = sizeof(sysctl_oom_dump_tasks),
1073 .proc_handler = &proc_dointvec,
1076 .ctl_name = VM_OVERCOMMIT_RATIO,
1077 .procname = "overcommit_ratio",
1078 .data = &sysctl_overcommit_ratio,
1079 .maxlen = sizeof(sysctl_overcommit_ratio),
1081 .proc_handler = &proc_dointvec,
1084 .ctl_name = VM_PAGE_CLUSTER,
1085 .procname = "page-cluster",
1086 .data = &page_cluster,
1087 .maxlen = sizeof(int),
1089 .proc_handler = &proc_dointvec,
1092 .ctl_name = VM_DIRTY_BACKGROUND,
1093 .procname = "dirty_background_ratio",
1094 .data = &dirty_background_ratio,
1095 .maxlen = sizeof(dirty_background_ratio),
1097 .proc_handler = &dirty_background_ratio_handler,
1098 .strategy = &sysctl_intvec,
1100 .extra2 = &one_hundred,
1103 .ctl_name = CTL_UNNUMBERED,
1104 .procname = "dirty_background_bytes",
1105 .data = &dirty_background_bytes,
1106 .maxlen = sizeof(dirty_background_bytes),
1108 .proc_handler = &dirty_background_bytes_handler,
1109 .strategy = &sysctl_intvec,
1113 .ctl_name = VM_DIRTY_RATIO,
1114 .procname = "dirty_ratio",
1115 .data = &vm_dirty_ratio,
1116 .maxlen = sizeof(vm_dirty_ratio),
1118 .proc_handler = &dirty_ratio_handler,
1119 .strategy = &sysctl_intvec,
1121 .extra2 = &one_hundred,
1124 .ctl_name = CTL_UNNUMBERED,
1125 .procname = "dirty_bytes",
1126 .data = &vm_dirty_bytes,
1127 .maxlen = sizeof(vm_dirty_bytes),
1129 .proc_handler = &dirty_bytes_handler,
1130 .strategy = &sysctl_intvec,
1131 .extra1 = &dirty_bytes_min,
1134 .procname = "dirty_writeback_centisecs",
1135 .data = &dirty_writeback_interval,
1136 .maxlen = sizeof(dirty_writeback_interval),
1138 .proc_handler = &dirty_writeback_centisecs_handler,
1141 .procname = "dirty_expire_centisecs",
1142 .data = &dirty_expire_interval,
1143 .maxlen = sizeof(dirty_expire_interval),
1145 .proc_handler = &proc_dointvec,
1148 .ctl_name = VM_NR_PDFLUSH_THREADS,
1149 .procname = "nr_pdflush_threads",
1150 .data = &nr_pdflush_threads,
1151 .maxlen = sizeof nr_pdflush_threads,
1152 .mode = 0444 /* read-only*/,
1153 .proc_handler = &proc_dointvec,
1156 .ctl_name = VM_SWAPPINESS,
1157 .procname = "swappiness",
1158 .data = &vm_swappiness,
1159 .maxlen = sizeof(vm_swappiness),
1161 .proc_handler = &proc_dointvec_minmax,
1162 .strategy = &sysctl_intvec,
1164 .extra2 = &one_hundred,
1166 #ifdef CONFIG_HUGETLB_PAGE
1168 .procname = "nr_hugepages",
1170 .maxlen = sizeof(unsigned long),
1172 .proc_handler = &hugetlb_sysctl_handler,
1173 .extra1 = (void *)&hugetlb_zero,
1174 .extra2 = (void *)&hugetlb_infinity,
1177 .ctl_name = VM_HUGETLB_GROUP,
1178 .procname = "hugetlb_shm_group",
1179 .data = &sysctl_hugetlb_shm_group,
1180 .maxlen = sizeof(gid_t),
1182 .proc_handler = &proc_dointvec,
1185 .ctl_name = CTL_UNNUMBERED,
1186 .procname = "hugepages_treat_as_movable",
1187 .data = &hugepages_treat_as_movable,
1188 .maxlen = sizeof(int),
1190 .proc_handler = &hugetlb_treat_movable_handler,
1193 .ctl_name = CTL_UNNUMBERED,
1194 .procname = "nr_overcommit_hugepages",
1196 .maxlen = sizeof(unsigned long),
1198 .proc_handler = &hugetlb_overcommit_handler,
1199 .extra1 = (void *)&hugetlb_zero,
1200 .extra2 = (void *)&hugetlb_infinity,
1204 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
1205 .procname = "lowmem_reserve_ratio",
1206 .data = &sysctl_lowmem_reserve_ratio,
1207 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1209 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
1210 .strategy = &sysctl_intvec,
1213 .ctl_name = VM_DROP_PAGECACHE,
1214 .procname = "drop_caches",
1215 .data = &sysctl_drop_caches,
1216 .maxlen = sizeof(int),
1218 .proc_handler = drop_caches_sysctl_handler,
1219 .strategy = &sysctl_intvec,
1222 .ctl_name = VM_MIN_FREE_KBYTES,
1223 .procname = "min_free_kbytes",
1224 .data = &min_free_kbytes,
1225 .maxlen = sizeof(min_free_kbytes),
1227 .proc_handler = &min_free_kbytes_sysctl_handler,
1228 .strategy = &sysctl_intvec,
1232 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
1233 .procname = "percpu_pagelist_fraction",
1234 .data = &percpu_pagelist_fraction,
1235 .maxlen = sizeof(percpu_pagelist_fraction),
1237 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
1238 .strategy = &sysctl_intvec,
1239 .extra1 = &min_percpu_pagelist_fract,
1243 .ctl_name = VM_MAX_MAP_COUNT,
1244 .procname = "max_map_count",
1245 .data = &sysctl_max_map_count,
1246 .maxlen = sizeof(sysctl_max_map_count),
1248 .proc_handler = &proc_dointvec
1252 .ctl_name = CTL_UNNUMBERED,
1253 .procname = "nr_trim_pages",
1254 .data = &sysctl_nr_trim_pages,
1255 .maxlen = sizeof(sysctl_nr_trim_pages),
1257 .proc_handler = &proc_dointvec_minmax,
1258 .strategy = &sysctl_intvec,
1263 .ctl_name = VM_LAPTOP_MODE,
1264 .procname = "laptop_mode",
1265 .data = &laptop_mode,
1266 .maxlen = sizeof(laptop_mode),
1268 .proc_handler = &proc_dointvec_jiffies,
1269 .strategy = &sysctl_jiffies,
1272 .ctl_name = VM_BLOCK_DUMP,
1273 .procname = "block_dump",
1274 .data = &block_dump,
1275 .maxlen = sizeof(block_dump),
1277 .proc_handler = &proc_dointvec,
1278 .strategy = &sysctl_intvec,
1282 .ctl_name = VM_VFS_CACHE_PRESSURE,
1283 .procname = "vfs_cache_pressure",
1284 .data = &sysctl_vfs_cache_pressure,
1285 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1287 .proc_handler = &proc_dointvec,
1288 .strategy = &sysctl_intvec,
1291 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1293 .ctl_name = VM_LEGACY_VA_LAYOUT,
1294 .procname = "legacy_va_layout",
1295 .data = &sysctl_legacy_va_layout,
1296 .maxlen = sizeof(sysctl_legacy_va_layout),
1298 .proc_handler = &proc_dointvec,
1299 .strategy = &sysctl_intvec,
1305 .ctl_name = VM_ZONE_RECLAIM_MODE,
1306 .procname = "zone_reclaim_mode",
1307 .data = &zone_reclaim_mode,
1308 .maxlen = sizeof(zone_reclaim_mode),
1310 .proc_handler = &proc_dointvec,
1311 .strategy = &sysctl_intvec,
1315 .ctl_name = VM_MIN_UNMAPPED,
1316 .procname = "min_unmapped_ratio",
1317 .data = &sysctl_min_unmapped_ratio,
1318 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1320 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1321 .strategy = &sysctl_intvec,
1323 .extra2 = &one_hundred,
1326 .ctl_name = VM_MIN_SLAB,
1327 .procname = "min_slab_ratio",
1328 .data = &sysctl_min_slab_ratio,
1329 .maxlen = sizeof(sysctl_min_slab_ratio),
1331 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1332 .strategy = &sysctl_intvec,
1334 .extra2 = &one_hundred,
1339 .ctl_name = CTL_UNNUMBERED,
1340 .procname = "stat_interval",
1341 .data = &sysctl_stat_interval,
1342 .maxlen = sizeof(sysctl_stat_interval),
1344 .proc_handler = &proc_dointvec_jiffies,
1345 .strategy = &sysctl_jiffies,
1349 .ctl_name = CTL_UNNUMBERED,
1350 .procname = "mmap_min_addr",
1351 .data = &dac_mmap_min_addr,
1352 .maxlen = sizeof(unsigned long),
1354 .proc_handler = &mmap_min_addr_handler,
1358 .ctl_name = CTL_UNNUMBERED,
1359 .procname = "numa_zonelist_order",
1360 .data = &numa_zonelist_order,
1361 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1363 .proc_handler = &numa_zonelist_order_handler,
1364 .strategy = &sysctl_string,
1367 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1368 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1370 .ctl_name = VM_VDSO_ENABLED,
1371 .procname = "vdso_enabled",
1372 .data = &vdso_enabled,
1373 .maxlen = sizeof(vdso_enabled),
1375 .proc_handler = &proc_dointvec,
1376 .strategy = &sysctl_intvec,
1380 #ifdef CONFIG_HIGHMEM
1382 .ctl_name = CTL_UNNUMBERED,
1383 .procname = "highmem_is_dirtyable",
1384 .data = &vm_highmem_is_dirtyable,
1385 .maxlen = sizeof(vm_highmem_is_dirtyable),
1387 .proc_handler = &proc_dointvec_minmax,
1388 .strategy = &sysctl_intvec,
1394 .ctl_name = CTL_UNNUMBERED,
1395 .procname = "scan_unevictable_pages",
1396 .data = &scan_unevictable_pages,
1397 .maxlen = sizeof(scan_unevictable_pages),
1399 .proc_handler = &scan_unevictable_handler,
1402 * NOTE: do not add new entries to this table unless you have read
1403 * Documentation/sysctl/ctl_unnumbered.txt
1408 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1409 static struct ctl_table binfmt_misc_table[] = {
1414 static struct ctl_table fs_table[] = {
1416 .ctl_name = FS_NRINODE,
1417 .procname = "inode-nr",
1418 .data = &inodes_stat,
1419 .maxlen = 2*sizeof(int),
1421 .proc_handler = &proc_dointvec,
1424 .ctl_name = FS_STATINODE,
1425 .procname = "inode-state",
1426 .data = &inodes_stat,
1427 .maxlen = 7*sizeof(int),
1429 .proc_handler = &proc_dointvec,
1432 .procname = "file-nr",
1433 .data = &files_stat,
1434 .maxlen = 3*sizeof(int),
1436 .proc_handler = &proc_nr_files,
1439 .ctl_name = FS_MAXFILE,
1440 .procname = "file-max",
1441 .data = &files_stat.max_files,
1442 .maxlen = sizeof(int),
1444 .proc_handler = &proc_dointvec,
1447 .ctl_name = CTL_UNNUMBERED,
1448 .procname = "nr_open",
1449 .data = &sysctl_nr_open,
1450 .maxlen = sizeof(int),
1452 .proc_handler = &proc_dointvec_minmax,
1453 .extra1 = &sysctl_nr_open_min,
1454 .extra2 = &sysctl_nr_open_max,
1457 .ctl_name = FS_DENTRY,
1458 .procname = "dentry-state",
1459 .data = &dentry_stat,
1460 .maxlen = 6*sizeof(int),
1462 .proc_handler = &proc_dointvec,
1465 .ctl_name = FS_OVERFLOWUID,
1466 .procname = "overflowuid",
1467 .data = &fs_overflowuid,
1468 .maxlen = sizeof(int),
1470 .proc_handler = &proc_dointvec_minmax,
1471 .strategy = &sysctl_intvec,
1472 .extra1 = &minolduid,
1473 .extra2 = &maxolduid,
1476 .ctl_name = FS_OVERFLOWGID,
1477 .procname = "overflowgid",
1478 .data = &fs_overflowgid,
1479 .maxlen = sizeof(int),
1481 .proc_handler = &proc_dointvec_minmax,
1482 .strategy = &sysctl_intvec,
1483 .extra1 = &minolduid,
1484 .extra2 = &maxolduid,
1486 #ifdef CONFIG_FILE_LOCKING
1488 .ctl_name = FS_LEASES,
1489 .procname = "leases-enable",
1490 .data = &leases_enable,
1491 .maxlen = sizeof(int),
1493 .proc_handler = &proc_dointvec,
1496 #ifdef CONFIG_DNOTIFY
1498 .ctl_name = FS_DIR_NOTIFY,
1499 .procname = "dir-notify-enable",
1500 .data = &dir_notify_enable,
1501 .maxlen = sizeof(int),
1503 .proc_handler = &proc_dointvec,
1507 #ifdef CONFIG_FILE_LOCKING
1509 .ctl_name = FS_LEASE_TIME,
1510 .procname = "lease-break-time",
1511 .data = &lease_break_time,
1512 .maxlen = sizeof(int),
1514 .proc_handler = &proc_dointvec,
1519 .procname = "aio-nr",
1521 .maxlen = sizeof(aio_nr),
1523 .proc_handler = &proc_doulongvec_minmax,
1526 .procname = "aio-max-nr",
1527 .data = &aio_max_nr,
1528 .maxlen = sizeof(aio_max_nr),
1530 .proc_handler = &proc_doulongvec_minmax,
1532 #endif /* CONFIG_AIO */
1533 #ifdef CONFIG_INOTIFY_USER
1535 .ctl_name = FS_INOTIFY,
1536 .procname = "inotify",
1538 .child = inotify_table,
1543 .procname = "epoll",
1545 .child = epoll_table,
1550 .ctl_name = KERN_SETUID_DUMPABLE,
1551 .procname = "suid_dumpable",
1552 .data = &suid_dumpable,
1553 .maxlen = sizeof(int),
1555 .proc_handler = &proc_dointvec_minmax,
1556 .strategy = &sysctl_intvec,
1560 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1562 .ctl_name = CTL_UNNUMBERED,
1563 .procname = "binfmt_misc",
1565 .child = binfmt_misc_table,
1569 * NOTE: do not add new entries to this table unless you have read
1570 * Documentation/sysctl/ctl_unnumbered.txt
1575 static struct ctl_table debug_table[] = {
1576 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1578 .ctl_name = CTL_UNNUMBERED,
1579 .procname = "exception-trace",
1580 .data = &show_unhandled_signals,
1581 .maxlen = sizeof(int),
1583 .proc_handler = proc_dointvec
1589 static struct ctl_table dev_table[] = {
1593 static DEFINE_SPINLOCK(sysctl_lock);
1595 /* called under sysctl_lock */
1596 static int use_table(struct ctl_table_header *p)
1598 if (unlikely(p->unregistering))
1604 /* called under sysctl_lock */
1605 static void unuse_table(struct ctl_table_header *p)
1608 if (unlikely(p->unregistering))
1609 complete(p->unregistering);
1612 /* called under sysctl_lock, will reacquire if has to wait */
1613 static void start_unregistering(struct ctl_table_header *p)
1616 * if p->used is 0, nobody will ever touch that entry again;
1617 * we'll eliminate all paths to it before dropping sysctl_lock
1619 if (unlikely(p->used)) {
1620 struct completion wait;
1621 init_completion(&wait);
1622 p->unregistering = &wait;
1623 spin_unlock(&sysctl_lock);
1624 wait_for_completion(&wait);
1625 spin_lock(&sysctl_lock);
1627 /* anything non-NULL; we'll never dereference it */
1628 p->unregistering = ERR_PTR(-EINVAL);
1631 * do not remove from the list until nobody holds it; walking the
1632 * list in do_sysctl() relies on that.
1634 list_del_init(&p->ctl_entry);
1637 void sysctl_head_get(struct ctl_table_header *head)
1639 spin_lock(&sysctl_lock);
1641 spin_unlock(&sysctl_lock);
1644 void sysctl_head_put(struct ctl_table_header *head)
1646 spin_lock(&sysctl_lock);
1649 spin_unlock(&sysctl_lock);
1652 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1656 spin_lock(&sysctl_lock);
1657 if (!use_table(head))
1658 head = ERR_PTR(-ENOENT);
1659 spin_unlock(&sysctl_lock);
1663 void sysctl_head_finish(struct ctl_table_header *head)
1667 spin_lock(&sysctl_lock);
1669 spin_unlock(&sysctl_lock);
1672 static struct ctl_table_set *
1673 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1675 struct ctl_table_set *set = &root->default_set;
1677 set = root->lookup(root, namespaces);
1681 static struct list_head *
1682 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1684 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1688 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1689 struct ctl_table_header *prev)
1691 struct ctl_table_root *root;
1692 struct list_head *header_list;
1693 struct ctl_table_header *head;
1694 struct list_head *tmp;
1696 spin_lock(&sysctl_lock);
1699 tmp = &prev->ctl_entry;
1703 tmp = &root_table_header.ctl_entry;
1705 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1707 if (!use_table(head))
1709 spin_unlock(&sysctl_lock);
1714 header_list = lookup_header_list(root, namespaces);
1715 if (tmp != header_list)
1719 root = list_entry(root->root_list.next,
1720 struct ctl_table_root, root_list);
1721 if (root == &sysctl_table_root)
1723 header_list = lookup_header_list(root, namespaces);
1724 } while (list_empty(header_list));
1725 tmp = header_list->next;
1728 spin_unlock(&sysctl_lock);
1732 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1734 return __sysctl_head_next(current->nsproxy, prev);
1737 void register_sysctl_root(struct ctl_table_root *root)
1739 spin_lock(&sysctl_lock);
1740 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1741 spin_unlock(&sysctl_lock);
1744 #ifdef CONFIG_SYSCTL_SYSCALL
1745 /* Perform the actual read/write of a sysctl table entry. */
1746 static int do_sysctl_strategy(struct ctl_table_root *root,
1747 struct ctl_table *table,
1748 void __user *oldval, size_t __user *oldlenp,
1749 void __user *newval, size_t newlen)
1757 if (sysctl_perm(root, table, op))
1760 if (table->strategy) {
1761 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1768 /* If there is no strategy routine, or if the strategy returns
1769 * zero, proceed with automatic r/w */
1770 if (table->data && table->maxlen) {
1771 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1778 static int parse_table(int __user *name, int nlen,
1779 void __user *oldval, size_t __user *oldlenp,
1780 void __user *newval, size_t newlen,
1781 struct ctl_table_root *root,
1782 struct ctl_table *table)
1788 if (get_user(n, name))
1790 for ( ; table->ctl_name || table->procname; table++) {
1791 if (!table->ctl_name)
1793 if (n == table->ctl_name) {
1796 if (sysctl_perm(root, table, MAY_EXEC))
1800 table = table->child;
1803 error = do_sysctl_strategy(root, table,
1812 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1813 void __user *newval, size_t newlen)
1815 struct ctl_table_header *head;
1816 int error = -ENOTDIR;
1818 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1822 if (!oldlenp || get_user(old_len, oldlenp))
1826 for (head = sysctl_head_next(NULL); head;
1827 head = sysctl_head_next(head)) {
1828 error = parse_table(name, nlen, oldval, oldlenp,
1830 head->root, head->ctl_table);
1831 if (error != -ENOTDIR) {
1832 sysctl_head_finish(head);
1839 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1841 struct __sysctl_args tmp;
1844 if (copy_from_user(&tmp, args, sizeof(tmp)))
1847 error = deprecated_sysctl_warning(&tmp);
1852 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1853 tmp.newval, tmp.newlen);
1858 #endif /* CONFIG_SYSCTL_SYSCALL */
1861 * sysctl_perm does NOT grant the superuser all rights automatically, because
1862 * some sysctl variables are readonly even to root.
1865 static int test_perm(int mode, int op)
1867 if (!current_euid())
1869 else if (in_egroup_p(0))
1871 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1876 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1881 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1885 if (root->permissions)
1886 mode = root->permissions(root, current->nsproxy, table);
1890 return test_perm(mode, op);
1893 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1895 for (; table->ctl_name || table->procname; table++) {
1896 table->parent = parent;
1898 sysctl_set_parent(table, table->child);
1902 static __init int sysctl_init(void)
1904 sysctl_set_parent(NULL, root_table);
1905 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1908 err = sysctl_check_table(current->nsproxy, root_table);
1914 core_initcall(sysctl_init);
1916 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1917 struct ctl_table *table)
1919 struct ctl_table *p;
1920 const char *s = branch->procname;
1922 /* branch should have named subdirectory as its first element */
1923 if (!s || !branch->child)
1926 /* ... and nothing else */
1927 if (branch[1].procname || branch[1].ctl_name)
1930 /* table should contain subdirectory with the same name */
1931 for (p = table; p->procname || p->ctl_name; p++) {
1934 if (p->procname && strcmp(p->procname, s) == 0)
1940 /* see if attaching q to p would be an improvement */
1941 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1943 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1944 struct ctl_table *next;
1946 int not_in_parent = !p->attached_by;
1948 while ((next = is_branch_in(by, to)) != NULL) {
1949 if (by == q->attached_by)
1951 if (to == p->attached_by)
1957 if (is_better && not_in_parent) {
1958 q->attached_by = by;
1959 q->attached_to = to;
1965 * __register_sysctl_paths - register a sysctl hierarchy
1966 * @root: List of sysctl headers to register on
1967 * @namespaces: Data to compute which lists of sysctl entries are visible
1968 * @path: The path to the directory the sysctl table is in.
1969 * @table: the top-level table structure
1971 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1972 * array. A completely 0 filled entry terminates the table.
1974 * The members of the &struct ctl_table structure are used as follows:
1976 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1977 * must be unique within that level of sysctl
1979 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1980 * enter a sysctl file
1982 * data - a pointer to data for use by proc_handler
1984 * maxlen - the maximum size in bytes of the data
1986 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1988 * child - a pointer to the child sysctl table if this entry is a directory, or
1991 * proc_handler - the text handler routine (described below)
1993 * strategy - the strategy routine (described below)
1995 * de - for internal use by the sysctl routines
1997 * extra1, extra2 - extra pointers usable by the proc handler routines
1999 * Leaf nodes in the sysctl tree will be represented by a single file
2000 * under /proc; non-leaf nodes will be represented by directories.
2002 * sysctl(2) can automatically manage read and write requests through
2003 * the sysctl table. The data and maxlen fields of the ctl_table
2004 * struct enable minimal validation of the values being written to be
2005 * performed, and the mode field allows minimal authentication.
2007 * More sophisticated management can be enabled by the provision of a
2008 * strategy routine with the table entry. This will be called before
2009 * any automatic read or write of the data is performed.
2011 * The strategy routine may return
2013 * < 0 - Error occurred (error is passed to user process)
2015 * 0 - OK - proceed with automatic read or write.
2017 * > 0 - OK - read or write has been done by the strategy routine, so
2018 * return immediately.
2020 * There must be a proc_handler routine for any terminal nodes
2021 * mirrored under /proc/sys (non-terminals are handled by a built-in
2022 * directory handler). Several default handlers are available to
2023 * cover common cases -
2025 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
2026 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
2027 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
2029 * It is the handler's job to read the input buffer from user memory
2030 * and process it. The handler should return 0 on success.
2032 * This routine returns %NULL on a failure to register, and a pointer
2033 * to the table header on success.
2035 struct ctl_table_header *__register_sysctl_paths(
2036 struct ctl_table_root *root,
2037 struct nsproxy *namespaces,
2038 const struct ctl_path *path, struct ctl_table *table)
2040 struct ctl_table_header *header;
2041 struct ctl_table *new, **prevp;
2042 unsigned int n, npath;
2043 struct ctl_table_set *set;
2045 /* Count the path components */
2046 for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
2050 * For each path component, allocate a 2-element ctl_table array.
2051 * The first array element will be filled with the sysctl entry
2052 * for this, the second will be the sentinel (ctl_name == 0).
2054 * We allocate everything in one go so that we don't have to
2055 * worry about freeing additional memory in unregister_sysctl_table.
2057 header = kzalloc(sizeof(struct ctl_table_header) +
2058 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
2062 new = (struct ctl_table *) (header + 1);
2064 /* Now connect the dots */
2065 prevp = &header->ctl_table;
2066 for (n = 0; n < npath; ++n, ++path) {
2067 /* Copy the procname */
2068 new->procname = path->procname;
2069 new->ctl_name = path->ctl_name;
2073 prevp = &new->child;
2078 header->ctl_table_arg = table;
2080 INIT_LIST_HEAD(&header->ctl_entry);
2082 header->unregistering = NULL;
2083 header->root = root;
2084 sysctl_set_parent(NULL, header->ctl_table);
2086 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2087 if (sysctl_check_table(namespaces, header->ctl_table)) {
2092 spin_lock(&sysctl_lock);
2093 header->set = lookup_header_set(root, namespaces);
2094 header->attached_by = header->ctl_table;
2095 header->attached_to = root_table;
2096 header->parent = &root_table_header;
2097 for (set = header->set; set; set = set->parent) {
2098 struct ctl_table_header *p;
2099 list_for_each_entry(p, &set->list, ctl_entry) {
2100 if (p->unregistering)
2102 try_attach(p, header);
2105 header->parent->count++;
2106 list_add_tail(&header->ctl_entry, &header->set->list);
2107 spin_unlock(&sysctl_lock);
2113 * register_sysctl_table_path - register a sysctl table hierarchy
2114 * @path: The path to the directory the sysctl table is in.
2115 * @table: the top-level table structure
2117 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2118 * array. A completely 0 filled entry terminates the table.
2120 * See __register_sysctl_paths for more details.
2122 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2123 struct ctl_table *table)
2125 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2130 * register_sysctl_table - register a sysctl table hierarchy
2131 * @table: the top-level table structure
2133 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2134 * array. A completely 0 filled entry terminates the table.
2136 * See register_sysctl_paths for more details.
2138 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2140 static const struct ctl_path null_path[] = { {} };
2142 return register_sysctl_paths(null_path, table);
2146 * unregister_sysctl_table - unregister a sysctl table hierarchy
2147 * @header: the header returned from register_sysctl_table
2149 * Unregisters the sysctl table and all children. proc entries may not
2150 * actually be removed until they are no longer used by anyone.
2152 void unregister_sysctl_table(struct ctl_table_header * header)
2159 spin_lock(&sysctl_lock);
2160 start_unregistering(header);
2161 if (!--header->parent->count) {
2163 kfree(header->parent);
2165 if (!--header->count)
2167 spin_unlock(&sysctl_lock);
2170 int sysctl_is_seen(struct ctl_table_header *p)
2172 struct ctl_table_set *set = p->set;
2174 spin_lock(&sysctl_lock);
2175 if (p->unregistering)
2177 else if (!set->is_seen)
2180 res = set->is_seen(set);
2181 spin_unlock(&sysctl_lock);
2185 void setup_sysctl_set(struct ctl_table_set *p,
2186 struct ctl_table_set *parent,
2187 int (*is_seen)(struct ctl_table_set *))
2189 INIT_LIST_HEAD(&p->list);
2190 p->parent = parent ? parent : &sysctl_table_root.default_set;
2191 p->is_seen = is_seen;
2194 #else /* !CONFIG_SYSCTL */
2195 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2200 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2201 struct ctl_table *table)
2206 void unregister_sysctl_table(struct ctl_table_header * table)
2210 void setup_sysctl_set(struct ctl_table_set *p,
2211 struct ctl_table_set *parent,
2212 int (*is_seen)(struct ctl_table_set *))
2216 void sysctl_head_put(struct ctl_table_header *head)
2220 #endif /* CONFIG_SYSCTL */
2226 #ifdef CONFIG_PROC_SYSCTL
2228 static int _proc_do_string(void* data, int maxlen, int write,
2229 struct file *filp, void __user *buffer,
2230 size_t *lenp, loff_t *ppos)
2236 if (!data || !maxlen || !*lenp) {
2244 while (len < *lenp) {
2245 if (get_user(c, p++))
2247 if (c == 0 || c == '\n')
2253 if(copy_from_user(data, buffer, len))
2255 ((char *) data)[len] = 0;
2273 if(copy_to_user(buffer, data, len))
2276 if(put_user('\n', ((char __user *) buffer) + len))
2287 * proc_dostring - read a string sysctl
2288 * @table: the sysctl table
2289 * @write: %TRUE if this is a write to the sysctl file
2290 * @filp: the file structure
2291 * @buffer: the user buffer
2292 * @lenp: the size of the user buffer
2293 * @ppos: file position
2295 * Reads/writes a string from/to the user buffer. If the kernel
2296 * buffer provided is not large enough to hold the string, the
2297 * string is truncated. The copied string is %NULL-terminated.
2298 * If the string is being read by the user process, it is copied
2299 * and a newline '\n' is added. It is truncated if the buffer is
2302 * Returns 0 on success.
2304 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2305 void __user *buffer, size_t *lenp, loff_t *ppos)
2307 return _proc_do_string(table->data, table->maxlen, write, filp,
2308 buffer, lenp, ppos);
2312 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2314 int write, void *data)
2317 *valp = *negp ? -*lvalp : *lvalp;
2322 *lvalp = (unsigned long)-val;
2325 *lvalp = (unsigned long)val;
2331 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2332 int write, struct file *filp, void __user *buffer,
2333 size_t *lenp, loff_t *ppos,
2334 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2335 int write, void *data),
2338 #define TMPBUFLEN 21
2339 int *i, vleft, first = 1, neg;
2343 char buf[TMPBUFLEN], *p;
2344 char __user *s = buffer;
2346 if (!tbl_data || !table->maxlen || !*lenp ||
2347 (*ppos && !write)) {
2352 i = (int *) tbl_data;
2353 vleft = table->maxlen / sizeof(*i);
2357 conv = do_proc_dointvec_conv;
2359 for (; left && vleft--; i++, first=0) {
2374 if (len > sizeof(buf) - 1)
2375 len = sizeof(buf) - 1;
2376 if (copy_from_user(buf, s, len))
2380 if (*p == '-' && left > 1) {
2384 if (*p < '0' || *p > '9')
2387 lval = simple_strtoul(p, &p, 0);
2390 if ((len < left) && *p && !isspace(*p))
2395 if (conv(&neg, &lval, i, 1, data))
2402 if (conv(&neg, &lval, i, 0, data))
2405 sprintf(p, "%s%lu", neg ? "-" : "", lval);
2409 if(copy_to_user(s, buf, len))
2416 if (!write && !first && left) {
2417 if(put_user('\n', s))
2424 if (get_user(c, s++))
2439 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2440 void __user *buffer, size_t *lenp, loff_t *ppos,
2441 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2442 int write, void *data),
2445 return __do_proc_dointvec(table->data, table, write, filp,
2446 buffer, lenp, ppos, conv, data);
2450 * proc_dointvec - read a vector of integers
2451 * @table: the sysctl table
2452 * @write: %TRUE if this is a write to the sysctl file
2453 * @filp: the file structure
2454 * @buffer: the user buffer
2455 * @lenp: the size of the user buffer
2456 * @ppos: file position
2458 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2459 * values from/to the user buffer, treated as an ASCII string.
2461 * Returns 0 on success.
2463 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2464 void __user *buffer, size_t *lenp, loff_t *ppos)
2466 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2471 * Taint values can only be increased
2472 * This means we can safely use a temporary.
2474 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2475 void __user *buffer, size_t *lenp, loff_t *ppos)
2478 unsigned long tmptaint = get_taint();
2481 if (write && !capable(CAP_SYS_ADMIN))
2486 err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2492 * Poor man's atomic or. Not worth adding a primitive
2493 * to everyone's atomic.h for this
2496 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2497 if ((tmptaint >> i) & 1)
2505 struct do_proc_dointvec_minmax_conv_param {
2510 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2512 int write, void *data)
2514 struct do_proc_dointvec_minmax_conv_param *param = data;
2516 int val = *negp ? -*lvalp : *lvalp;
2517 if ((param->min && *param->min > val) ||
2518 (param->max && *param->max < val))
2525 *lvalp = (unsigned long)-val;
2528 *lvalp = (unsigned long)val;
2535 * proc_dointvec_minmax - read a vector of integers with min/max values
2536 * @table: the sysctl table
2537 * @write: %TRUE if this is a write to the sysctl file
2538 * @filp: the file structure
2539 * @buffer: the user buffer
2540 * @lenp: the size of the user buffer
2541 * @ppos: file position
2543 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2544 * values from/to the user buffer, treated as an ASCII string.
2546 * This routine will ensure the values are within the range specified by
2547 * table->extra1 (min) and table->extra2 (max).
2549 * Returns 0 on success.
2551 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2552 void __user *buffer, size_t *lenp, loff_t *ppos)
2554 struct do_proc_dointvec_minmax_conv_param param = {
2555 .min = (int *) table->extra1,
2556 .max = (int *) table->extra2,
2558 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2559 do_proc_dointvec_minmax_conv, ¶m);
2562 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2564 void __user *buffer,
2565 size_t *lenp, loff_t *ppos,
2566 unsigned long convmul,
2567 unsigned long convdiv)
2569 #define TMPBUFLEN 21
2570 unsigned long *i, *min, *max, val;
2571 int vleft, first=1, neg;
2573 char buf[TMPBUFLEN], *p;
2574 char __user *s = buffer;
2576 if (!data || !table->maxlen || !*lenp ||
2577 (*ppos && !write)) {
2582 i = (unsigned long *) data;
2583 min = (unsigned long *) table->extra1;
2584 max = (unsigned long *) table->extra2;
2585 vleft = table->maxlen / sizeof(unsigned long);
2588 for (; left && vleft--; i++, min++, max++, first=0) {
2603 if (len > TMPBUFLEN-1)
2605 if (copy_from_user(buf, s, len))
2609 if (*p == '-' && left > 1) {
2613 if (*p < '0' || *p > '9')
2615 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2617 if ((len < left) && *p && !isspace(*p))
2626 if ((min && val < *min) || (max && val > *max))
2633 sprintf(p, "%lu", convdiv * (*i) / convmul);
2637 if(copy_to_user(s, buf, len))
2644 if (!write && !first && left) {
2645 if(put_user('\n', s))
2652 if (get_user(c, s++))
2667 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2669 void __user *buffer,
2670 size_t *lenp, loff_t *ppos,
2671 unsigned long convmul,
2672 unsigned long convdiv)
2674 return __do_proc_doulongvec_minmax(table->data, table, write,
2675 filp, buffer, lenp, ppos, convmul, convdiv);
2679 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2680 * @table: the sysctl table
2681 * @write: %TRUE if this is a write to the sysctl file
2682 * @filp: the file structure
2683 * @buffer: the user buffer
2684 * @lenp: the size of the user buffer
2685 * @ppos: file position
2687 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2688 * values from/to the user buffer, treated as an ASCII string.
2690 * This routine will ensure the values are within the range specified by
2691 * table->extra1 (min) and table->extra2 (max).
2693 * Returns 0 on success.
2695 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2696 void __user *buffer, size_t *lenp, loff_t *ppos)
2698 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2702 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2703 * @table: the sysctl table
2704 * @write: %TRUE if this is a write to the sysctl file
2705 * @filp: the file structure
2706 * @buffer: the user buffer
2707 * @lenp: the size of the user buffer
2708 * @ppos: file position
2710 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2711 * values from/to the user buffer, treated as an ASCII string. The values
2712 * are treated as milliseconds, and converted to jiffies when they are stored.
2714 * This routine will ensure the values are within the range specified by
2715 * table->extra1 (min) and table->extra2 (max).
2717 * Returns 0 on success.
2719 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2721 void __user *buffer,
2722 size_t *lenp, loff_t *ppos)
2724 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2725 lenp, ppos, HZ, 1000l);
2729 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2731 int write, void *data)
2734 if (*lvalp > LONG_MAX / HZ)
2736 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2742 lval = (unsigned long)-val;
2745 lval = (unsigned long)val;
2752 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2754 int write, void *data)
2757 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2759 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2765 lval = (unsigned long)-val;
2768 lval = (unsigned long)val;
2770 *lvalp = jiffies_to_clock_t(lval);
2775 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2777 int write, void *data)
2780 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2786 lval = (unsigned long)-val;
2789 lval = (unsigned long)val;
2791 *lvalp = jiffies_to_msecs(lval);
2797 * proc_dointvec_jiffies - read a vector of integers as seconds
2798 * @table: the sysctl table
2799 * @write: %TRUE if this is a write to the sysctl file
2800 * @filp: the file structure
2801 * @buffer: the user buffer
2802 * @lenp: the size of the user buffer
2803 * @ppos: file position
2805 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2806 * values from/to the user buffer, treated as an ASCII string.
2807 * The values read are assumed to be in seconds, and are converted into
2810 * Returns 0 on success.
2812 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2813 void __user *buffer, size_t *lenp, loff_t *ppos)
2815 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2816 do_proc_dointvec_jiffies_conv,NULL);
2820 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2821 * @table: the sysctl table
2822 * @write: %TRUE if this is a write to the sysctl file
2823 * @filp: the file structure
2824 * @buffer: the user buffer
2825 * @lenp: the size of the user buffer
2826 * @ppos: pointer to the file position
2828 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2829 * values from/to the user buffer, treated as an ASCII string.
2830 * The values read are assumed to be in 1/USER_HZ seconds, and
2831 * are converted into jiffies.
2833 * Returns 0 on success.
2835 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2836 void __user *buffer, size_t *lenp, loff_t *ppos)
2838 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2839 do_proc_dointvec_userhz_jiffies_conv,NULL);
2843 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2844 * @table: the sysctl table
2845 * @write: %TRUE if this is a write to the sysctl file
2846 * @filp: the file structure
2847 * @buffer: the user buffer
2848 * @lenp: the size of the user buffer
2849 * @ppos: file position
2850 * @ppos: the current position in the file
2852 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2853 * values from/to the user buffer, treated as an ASCII string.
2854 * The values read are assumed to be in 1/1000 seconds, and
2855 * are converted into jiffies.
2857 * Returns 0 on success.
2859 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2860 void __user *buffer, size_t *lenp, loff_t *ppos)
2862 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2863 do_proc_dointvec_ms_jiffies_conv, NULL);
2866 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2867 void __user *buffer, size_t *lenp, loff_t *ppos)
2869 struct pid *new_pid;
2873 tmp = pid_vnr(cad_pid);
2875 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2876 lenp, ppos, NULL, NULL);
2880 new_pid = find_get_pid(tmp);
2884 put_pid(xchg(&cad_pid, new_pid));
2888 #else /* CONFIG_PROC_FS */
2890 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2891 void __user *buffer, size_t *lenp, loff_t *ppos)
2896 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2897 void __user *buffer, size_t *lenp, loff_t *ppos)
2902 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2903 void __user *buffer, size_t *lenp, loff_t *ppos)
2908 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2909 void __user *buffer, size_t *lenp, loff_t *ppos)
2914 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2915 void __user *buffer, size_t *lenp, loff_t *ppos)
2920 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2921 void __user *buffer, size_t *lenp, loff_t *ppos)
2926 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2927 void __user *buffer, size_t *lenp, loff_t *ppos)
2932 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2934 void __user *buffer,
2935 size_t *lenp, loff_t *ppos)
2941 #endif /* CONFIG_PROC_FS */
2944 #ifdef CONFIG_SYSCTL_SYSCALL
2946 * General sysctl support routines
2949 /* The generic sysctl data routine (used if no strategy routine supplied) */
2950 int sysctl_data(struct ctl_table *table,
2951 void __user *oldval, size_t __user *oldlenp,
2952 void __user *newval, size_t newlen)
2956 /* Get out of I don't have a variable */
2957 if (!table->data || !table->maxlen)
2960 if (oldval && oldlenp) {
2961 if (get_user(len, oldlenp))
2964 if (len > table->maxlen)
2965 len = table->maxlen;
2966 if (copy_to_user(oldval, table->data, len))
2968 if (put_user(len, oldlenp))
2973 if (newval && newlen) {
2974 if (newlen > table->maxlen)
2975 newlen = table->maxlen;
2977 if (copy_from_user(table->data, newval, newlen))
2983 /* The generic string strategy routine: */
2984 int sysctl_string(struct ctl_table *table,
2985 void __user *oldval, size_t __user *oldlenp,
2986 void __user *newval, size_t newlen)
2988 if (!table->data || !table->maxlen)
2991 if (oldval && oldlenp) {
2993 if (get_user(bufsize, oldlenp))
2996 size_t len = strlen(table->data), copied;
2998 /* This shouldn't trigger for a well-formed sysctl */
2999 if (len > table->maxlen)
3000 len = table->maxlen;
3002 /* Copy up to a max of bufsize-1 bytes of the string */
3003 copied = (len >= bufsize) ? bufsize - 1 : len;
3005 if (copy_to_user(oldval, table->data, copied) ||
3006 put_user(0, (char __user *)(oldval + copied)))
3008 if (put_user(len, oldlenp))
3012 if (newval && newlen) {
3013 size_t len = newlen;
3014 if (len > table->maxlen)
3015 len = table->maxlen;
3016 if(copy_from_user(table->data, newval, len))
3018 if (len == table->maxlen)
3020 ((char *) table->data)[len] = 0;
3026 * This function makes sure that all of the integers in the vector
3027 * are between the minimum and maximum values given in the arrays
3028 * table->extra1 and table->extra2, respectively.
3030 int sysctl_intvec(struct ctl_table *table,
3031 void __user *oldval, size_t __user *oldlenp,
3032 void __user *newval, size_t newlen)
3035 if (newval && newlen) {
3036 int __user *vec = (int __user *) newval;
3037 int *min = (int *) table->extra1;
3038 int *max = (int *) table->extra2;
3042 if (newlen % sizeof(int) != 0)
3045 if (!table->extra1 && !table->extra2)
3048 if (newlen > table->maxlen)
3049 newlen = table->maxlen;
3050 length = newlen / sizeof(int);
3052 for (i = 0; i < length; i++) {
3054 if (get_user(value, vec + i))
3056 if (min && value < min[i])
3058 if (max && value > max[i])
3065 /* Strategy function to convert jiffies to seconds */
3066 int sysctl_jiffies(struct ctl_table *table,
3067 void __user *oldval, size_t __user *oldlenp,
3068 void __user *newval, size_t newlen)
3070 if (oldval && oldlenp) {
3073 if (get_user(olen, oldlenp))
3078 if (olen < sizeof(int))
3081 val = *(int *)(table->data) / HZ;
3082 if (put_user(val, (int __user *)oldval))
3084 if (put_user(sizeof(int), oldlenp))
3088 if (newval && newlen) {
3090 if (newlen != sizeof(int))
3092 if (get_user(new, (int __user *)newval))
3094 *(int *)(table->data) = new*HZ;
3099 /* Strategy function to convert jiffies to seconds */
3100 int sysctl_ms_jiffies(struct ctl_table *table,
3101 void __user *oldval, size_t __user *oldlenp,
3102 void __user *newval, size_t newlen)
3104 if (oldval && oldlenp) {
3107 if (get_user(olen, oldlenp))
3112 if (olen < sizeof(int))
3115 val = jiffies_to_msecs(*(int *)(table->data));
3116 if (put_user(val, (int __user *)oldval))
3118 if (put_user(sizeof(int), oldlenp))
3122 if (newval && newlen) {
3124 if (newlen != sizeof(int))
3126 if (get_user(new, (int __user *)newval))
3128 *(int *)(table->data) = msecs_to_jiffies(new);
3135 #else /* CONFIG_SYSCTL_SYSCALL */
3138 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3140 struct __sysctl_args tmp;
3143 if (copy_from_user(&tmp, args, sizeof(tmp)))
3146 error = deprecated_sysctl_warning(&tmp);
3148 /* If no error reading the parameters then just -ENOSYS ... */
3155 int sysctl_data(struct ctl_table *table,
3156 void __user *oldval, size_t __user *oldlenp,
3157 void __user *newval, size_t newlen)
3162 int sysctl_string(struct ctl_table *table,
3163 void __user *oldval, size_t __user *oldlenp,
3164 void __user *newval, size_t newlen)
3169 int sysctl_intvec(struct ctl_table *table,
3170 void __user *oldval, size_t __user *oldlenp,
3171 void __user *newval, size_t newlen)
3176 int sysctl_jiffies(struct ctl_table *table,
3177 void __user *oldval, size_t __user *oldlenp,
3178 void __user *newval, size_t newlen)
3183 int sysctl_ms_jiffies(struct ctl_table *table,
3184 void __user *oldval, size_t __user *oldlenp,
3185 void __user *newval, size_t newlen)
3190 #endif /* CONFIG_SYSCTL_SYSCALL */
3192 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3194 static int msg_count;
3195 int name[CTL_MAXNAME];
3198 /* Check args->nlen. */
3199 if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3202 /* Read in the sysctl name for better debug message logging */
3203 for (i = 0; i < args->nlen; i++)
3204 if (get_user(name[i], args->name + i))
3207 /* Ignore accesses to kernel.version */
3208 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3211 if (msg_count < 5) {
3214 "warning: process `%s' used the deprecated sysctl "
3215 "system call with ", current->comm);
3216 for (i = 0; i < args->nlen; i++)
3217 printk("%d.", name[i]);
3224 * No sense putting this after each symbol definition, twice,
3225 * exception granted :-)
3227 EXPORT_SYMBOL(proc_dointvec);
3228 EXPORT_SYMBOL(proc_dointvec_jiffies);
3229 EXPORT_SYMBOL(proc_dointvec_minmax);
3230 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3231 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3232 EXPORT_SYMBOL(proc_dostring);
3233 EXPORT_SYMBOL(proc_doulongvec_minmax);
3234 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3235 EXPORT_SYMBOL(register_sysctl_table);
3236 EXPORT_SYMBOL(register_sysctl_paths);
3237 EXPORT_SYMBOL(sysctl_intvec);
3238 EXPORT_SYMBOL(sysctl_jiffies);
3239 EXPORT_SYMBOL(sysctl_ms_jiffies);
3240 EXPORT_SYMBOL(sysctl_string);
3241 EXPORT_SYMBOL(sysctl_data);
3242 EXPORT_SYMBOL(unregister_sysctl_table);