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/utsname.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_counter.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[];
80 extern int min_free_kbytes;
81 extern int pid_max_min, pid_max_max;
82 extern int sysctl_drop_caches;
83 extern int percpu_pagelist_fraction;
84 extern int compat_log;
85 extern int latencytop_enabled;
86 extern int sysctl_nr_open_min, sysctl_nr_open_max;
88 extern int sysctl_nr_trim_pages;
90 #ifdef CONFIG_RCU_TORTURE_TEST
91 extern int rcutorture_runnable;
92 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
94 /* Constants used for minimum and maximum */
95 #ifdef CONFIG_DETECT_SOFTLOCKUP
96 static int sixty = 60;
97 static int neg_one = -1;
101 static int __maybe_unused one = 1;
102 static int __maybe_unused two = 2;
103 static unsigned long one_ul = 1;
104 static int one_hundred = 100;
105 static int one_thousand = 1000;
107 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
108 static int maxolduid = 65535;
109 static int minolduid;
110 static int min_percpu_pagelist_fract = 8;
112 static int ngroups_max = NGROUPS_MAX;
114 #ifdef CONFIG_MODULES
115 extern char modprobe_path[];
117 #ifdef CONFIG_CHR_DEV_SG
118 extern int sg_big_buff;
122 #include <asm/system.h>
125 #ifdef CONFIG_SPARC64
126 extern int sysctl_tsb_ratio;
130 extern int pwrsw_enabled;
131 extern int unaligned_enabled;
135 #ifdef CONFIG_MATHEMU
136 extern int sysctl_ieee_emulation_warnings;
138 extern int sysctl_userprocess_debug;
139 extern int spin_retry;
142 #ifdef CONFIG_BSD_PROCESS_ACCT
143 extern int acct_parm[];
147 extern int no_unaligned_warning;
148 extern int unaligned_dump_stack;
151 #ifdef CONFIG_RT_MUTEXES
152 extern int max_lock_depth;
155 #ifdef CONFIG_PROC_SYSCTL
156 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
157 void __user *buffer, size_t *lenp, loff_t *ppos);
158 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
159 void __user *buffer, size_t *lenp, loff_t *ppos);
162 static struct ctl_table root_table[];
163 static struct ctl_table_root sysctl_table_root;
164 static struct ctl_table_header root_table_header = {
166 .ctl_table = root_table,
167 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
168 .root = &sysctl_table_root,
169 .set = &sysctl_table_root.default_set,
171 static struct ctl_table_root sysctl_table_root = {
172 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
173 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
176 static struct ctl_table kern_table[];
177 static struct ctl_table vm_table[];
178 static struct ctl_table fs_table[];
179 static struct ctl_table debug_table[];
180 static struct ctl_table dev_table[];
181 extern struct ctl_table random_table[];
182 #ifdef CONFIG_INOTIFY_USER
183 extern struct ctl_table inotify_table[];
186 extern struct ctl_table epoll_table[];
189 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
190 int sysctl_legacy_va_layout;
193 extern int prove_locking;
194 extern int lock_stat;
196 /* The default sysctl tables: */
198 static struct ctl_table root_table[] = {
200 .ctl_name = CTL_KERN,
201 .procname = "kernel",
218 .ctl_name = CTL_DEBUG,
221 .child = debug_table,
230 * NOTE: do not add new entries to this table unless you have read
231 * Documentation/sysctl/ctl_unnumbered.txt
236 #ifdef CONFIG_SCHED_DEBUG
237 static int min_sched_granularity_ns = 100000; /* 100 usecs */
238 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
239 static int min_wakeup_granularity_ns; /* 0 usecs */
240 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
243 static struct ctl_table kern_table[] = {
244 #ifdef CONFIG_SCHED_DEBUG
246 .ctl_name = CTL_UNNUMBERED,
247 .procname = "sched_min_granularity_ns",
248 .data = &sysctl_sched_min_granularity,
249 .maxlen = sizeof(unsigned int),
251 .proc_handler = &sched_nr_latency_handler,
252 .strategy = &sysctl_intvec,
253 .extra1 = &min_sched_granularity_ns,
254 .extra2 = &max_sched_granularity_ns,
257 .ctl_name = CTL_UNNUMBERED,
258 .procname = "sched_latency_ns",
259 .data = &sysctl_sched_latency,
260 .maxlen = sizeof(unsigned int),
262 .proc_handler = &sched_nr_latency_handler,
263 .strategy = &sysctl_intvec,
264 .extra1 = &min_sched_granularity_ns,
265 .extra2 = &max_sched_granularity_ns,
268 .ctl_name = CTL_UNNUMBERED,
269 .procname = "sched_wakeup_granularity_ns",
270 .data = &sysctl_sched_wakeup_granularity,
271 .maxlen = sizeof(unsigned int),
273 .proc_handler = &proc_dointvec_minmax,
274 .strategy = &sysctl_intvec,
275 .extra1 = &min_wakeup_granularity_ns,
276 .extra2 = &max_wakeup_granularity_ns,
279 .ctl_name = CTL_UNNUMBERED,
280 .procname = "sched_shares_ratelimit",
281 .data = &sysctl_sched_shares_ratelimit,
282 .maxlen = sizeof(unsigned int),
284 .proc_handler = &proc_dointvec,
287 .ctl_name = CTL_UNNUMBERED,
288 .procname = "sched_shares_thresh",
289 .data = &sysctl_sched_shares_thresh,
290 .maxlen = sizeof(unsigned int),
292 .proc_handler = &proc_dointvec_minmax,
293 .strategy = &sysctl_intvec,
297 .ctl_name = CTL_UNNUMBERED,
298 .procname = "sched_child_runs_first",
299 .data = &sysctl_sched_child_runs_first,
300 .maxlen = sizeof(unsigned int),
302 .proc_handler = &proc_dointvec,
305 .ctl_name = CTL_UNNUMBERED,
306 .procname = "sched_features",
307 .data = &sysctl_sched_features,
308 .maxlen = sizeof(unsigned int),
310 .proc_handler = &proc_dointvec,
313 .ctl_name = CTL_UNNUMBERED,
314 .procname = "sched_migration_cost",
315 .data = &sysctl_sched_migration_cost,
316 .maxlen = sizeof(unsigned int),
318 .proc_handler = &proc_dointvec,
321 .ctl_name = CTL_UNNUMBERED,
322 .procname = "sched_nr_migrate",
323 .data = &sysctl_sched_nr_migrate,
324 .maxlen = sizeof(unsigned int),
326 .proc_handler = &proc_dointvec,
330 .ctl_name = CTL_UNNUMBERED,
331 .procname = "sched_rt_period_us",
332 .data = &sysctl_sched_rt_period,
333 .maxlen = sizeof(unsigned int),
335 .proc_handler = &sched_rt_handler,
338 .ctl_name = CTL_UNNUMBERED,
339 .procname = "sched_rt_runtime_us",
340 .data = &sysctl_sched_rt_runtime,
341 .maxlen = sizeof(int),
343 .proc_handler = &sched_rt_handler,
346 .ctl_name = CTL_UNNUMBERED,
347 .procname = "sched_compat_yield",
348 .data = &sysctl_sched_compat_yield,
349 .maxlen = sizeof(unsigned int),
351 .proc_handler = &proc_dointvec,
353 #ifdef CONFIG_PROVE_LOCKING
355 .ctl_name = CTL_UNNUMBERED,
356 .procname = "prove_locking",
357 .data = &prove_locking,
358 .maxlen = sizeof(int),
360 .proc_handler = &proc_dointvec,
363 #ifdef CONFIG_LOCK_STAT
365 .ctl_name = CTL_UNNUMBERED,
366 .procname = "lock_stat",
368 .maxlen = sizeof(int),
370 .proc_handler = &proc_dointvec,
374 .ctl_name = KERN_PANIC,
376 .data = &panic_timeout,
377 .maxlen = sizeof(int),
379 .proc_handler = &proc_dointvec,
382 .ctl_name = KERN_CORE_USES_PID,
383 .procname = "core_uses_pid",
384 .data = &core_uses_pid,
385 .maxlen = sizeof(int),
387 .proc_handler = &proc_dointvec,
390 .ctl_name = KERN_CORE_PATTERN,
391 .procname = "core_pattern",
392 .data = core_pattern,
393 .maxlen = CORENAME_MAX_SIZE,
395 .proc_handler = &proc_dostring,
396 .strategy = &sysctl_string,
398 #ifdef CONFIG_PROC_SYSCTL
400 .procname = "tainted",
401 .maxlen = sizeof(long),
403 .proc_handler = &proc_taint,
406 #ifdef CONFIG_LATENCYTOP
408 .procname = "latencytop",
409 .data = &latencytop_enabled,
410 .maxlen = sizeof(int),
412 .proc_handler = &proc_dointvec,
415 #ifdef CONFIG_BLK_DEV_INITRD
417 .ctl_name = KERN_REALROOTDEV,
418 .procname = "real-root-dev",
419 .data = &real_root_dev,
420 .maxlen = sizeof(int),
422 .proc_handler = &proc_dointvec,
426 .ctl_name = CTL_UNNUMBERED,
427 .procname = "print-fatal-signals",
428 .data = &print_fatal_signals,
429 .maxlen = sizeof(int),
431 .proc_handler = &proc_dointvec,
435 .ctl_name = KERN_SPARC_REBOOT,
436 .procname = "reboot-cmd",
437 .data = reboot_command,
440 .proc_handler = &proc_dostring,
441 .strategy = &sysctl_string,
444 .ctl_name = KERN_SPARC_STOP_A,
445 .procname = "stop-a",
446 .data = &stop_a_enabled,
447 .maxlen = sizeof (int),
449 .proc_handler = &proc_dointvec,
452 .ctl_name = KERN_SPARC_SCONS_PWROFF,
453 .procname = "scons-poweroff",
454 .data = &scons_pwroff,
455 .maxlen = sizeof (int),
457 .proc_handler = &proc_dointvec,
460 #ifdef CONFIG_SPARC64
462 .ctl_name = CTL_UNNUMBERED,
463 .procname = "tsb-ratio",
464 .data = &sysctl_tsb_ratio,
465 .maxlen = sizeof (int),
467 .proc_handler = &proc_dointvec,
472 .ctl_name = KERN_HPPA_PWRSW,
473 .procname = "soft-power",
474 .data = &pwrsw_enabled,
475 .maxlen = sizeof (int),
477 .proc_handler = &proc_dointvec,
480 .ctl_name = KERN_HPPA_UNALIGNED,
481 .procname = "unaligned-trap",
482 .data = &unaligned_enabled,
483 .maxlen = sizeof (int),
485 .proc_handler = &proc_dointvec,
489 .ctl_name = KERN_CTLALTDEL,
490 .procname = "ctrl-alt-del",
492 .maxlen = sizeof(int),
494 .proc_handler = &proc_dointvec,
496 #ifdef CONFIG_FUNCTION_TRACER
498 .ctl_name = CTL_UNNUMBERED,
499 .procname = "ftrace_enabled",
500 .data = &ftrace_enabled,
501 .maxlen = sizeof(int),
503 .proc_handler = &ftrace_enable_sysctl,
506 #ifdef CONFIG_STACK_TRACER
508 .ctl_name = CTL_UNNUMBERED,
509 .procname = "stack_tracer_enabled",
510 .data = &stack_tracer_enabled,
511 .maxlen = sizeof(int),
513 .proc_handler = &stack_trace_sysctl,
516 #ifdef CONFIG_TRACING
518 .ctl_name = CTL_UNNUMBERED,
519 .procname = "ftrace_dump_on_oops",
520 .data = &ftrace_dump_on_oops,
521 .maxlen = sizeof(int),
523 .proc_handler = &proc_dointvec,
526 #ifdef CONFIG_MODULES
528 .ctl_name = KERN_MODPROBE,
529 .procname = "modprobe",
530 .data = &modprobe_path,
531 .maxlen = KMOD_PATH_LEN,
533 .proc_handler = &proc_dostring,
534 .strategy = &sysctl_string,
537 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
539 .ctl_name = KERN_HOTPLUG,
540 .procname = "hotplug",
541 .data = &uevent_helper,
542 .maxlen = UEVENT_HELPER_PATH_LEN,
544 .proc_handler = &proc_dostring,
545 .strategy = &sysctl_string,
548 #ifdef CONFIG_CHR_DEV_SG
550 .ctl_name = KERN_SG_BIG_BUFF,
551 .procname = "sg-big-buff",
552 .data = &sg_big_buff,
553 .maxlen = sizeof (int),
555 .proc_handler = &proc_dointvec,
558 #ifdef CONFIG_BSD_PROCESS_ACCT
560 .ctl_name = KERN_ACCT,
563 .maxlen = 3*sizeof(int),
565 .proc_handler = &proc_dointvec,
568 #ifdef CONFIG_MAGIC_SYSRQ
570 .ctl_name = KERN_SYSRQ,
572 .data = &__sysrq_enabled,
573 .maxlen = sizeof (int),
575 .proc_handler = &proc_dointvec,
578 #ifdef CONFIG_PROC_SYSCTL
580 .procname = "cad_pid",
582 .maxlen = sizeof (int),
584 .proc_handler = &proc_do_cad_pid,
588 .ctl_name = KERN_MAX_THREADS,
589 .procname = "threads-max",
590 .data = &max_threads,
591 .maxlen = sizeof(int),
593 .proc_handler = &proc_dointvec,
596 .ctl_name = KERN_RANDOM,
597 .procname = "random",
599 .child = random_table,
602 .ctl_name = KERN_OVERFLOWUID,
603 .procname = "overflowuid",
604 .data = &overflowuid,
605 .maxlen = sizeof(int),
607 .proc_handler = &proc_dointvec_minmax,
608 .strategy = &sysctl_intvec,
609 .extra1 = &minolduid,
610 .extra2 = &maxolduid,
613 .ctl_name = KERN_OVERFLOWGID,
614 .procname = "overflowgid",
615 .data = &overflowgid,
616 .maxlen = sizeof(int),
618 .proc_handler = &proc_dointvec_minmax,
619 .strategy = &sysctl_intvec,
620 .extra1 = &minolduid,
621 .extra2 = &maxolduid,
624 #ifdef CONFIG_MATHEMU
626 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
627 .procname = "ieee_emulation_warnings",
628 .data = &sysctl_ieee_emulation_warnings,
629 .maxlen = sizeof(int),
631 .proc_handler = &proc_dointvec,
635 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
636 .procname = "userprocess_debug",
637 .data = &sysctl_userprocess_debug,
638 .maxlen = sizeof(int),
640 .proc_handler = &proc_dointvec,
644 .ctl_name = KERN_PIDMAX,
645 .procname = "pid_max",
647 .maxlen = sizeof (int),
649 .proc_handler = &proc_dointvec_minmax,
650 .strategy = sysctl_intvec,
651 .extra1 = &pid_max_min,
652 .extra2 = &pid_max_max,
655 .ctl_name = KERN_PANIC_ON_OOPS,
656 .procname = "panic_on_oops",
657 .data = &panic_on_oops,
658 .maxlen = sizeof(int),
660 .proc_handler = &proc_dointvec,
662 #if defined CONFIG_PRINTK
664 .ctl_name = KERN_PRINTK,
665 .procname = "printk",
666 .data = &console_loglevel,
667 .maxlen = 4*sizeof(int),
669 .proc_handler = &proc_dointvec,
672 .ctl_name = KERN_PRINTK_RATELIMIT,
673 .procname = "printk_ratelimit",
674 .data = &printk_ratelimit_state.interval,
675 .maxlen = sizeof(int),
677 .proc_handler = &proc_dointvec_jiffies,
678 .strategy = &sysctl_jiffies,
681 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
682 .procname = "printk_ratelimit_burst",
683 .data = &printk_ratelimit_state.burst,
684 .maxlen = sizeof(int),
686 .proc_handler = &proc_dointvec,
690 .ctl_name = KERN_NGROUPS_MAX,
691 .procname = "ngroups_max",
692 .data = &ngroups_max,
693 .maxlen = sizeof (int),
695 .proc_handler = &proc_dointvec,
697 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
699 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
700 .procname = "unknown_nmi_panic",
701 .data = &unknown_nmi_panic,
702 .maxlen = sizeof (int),
704 .proc_handler = &proc_dointvec,
707 .procname = "nmi_watchdog",
708 .data = &nmi_watchdog_enabled,
709 .maxlen = sizeof (int),
711 .proc_handler = &proc_nmi_enabled,
714 #if defined(CONFIG_X86)
716 .ctl_name = KERN_PANIC_ON_NMI,
717 .procname = "panic_on_unrecovered_nmi",
718 .data = &panic_on_unrecovered_nmi,
719 .maxlen = sizeof(int),
721 .proc_handler = &proc_dointvec,
724 .ctl_name = KERN_BOOTLOADER_TYPE,
725 .procname = "bootloader_type",
726 .data = &bootloader_type,
727 .maxlen = sizeof (int),
729 .proc_handler = &proc_dointvec,
732 .ctl_name = CTL_UNNUMBERED,
733 .procname = "kstack_depth_to_print",
734 .data = &kstack_depth_to_print,
735 .maxlen = sizeof(int),
737 .proc_handler = &proc_dointvec,
740 .ctl_name = CTL_UNNUMBERED,
741 .procname = "io_delay_type",
742 .data = &io_delay_type,
743 .maxlen = sizeof(int),
745 .proc_handler = &proc_dointvec,
748 #if defined(CONFIG_MMU)
750 .ctl_name = KERN_RANDOMIZE,
751 .procname = "randomize_va_space",
752 .data = &randomize_va_space,
753 .maxlen = sizeof(int),
755 .proc_handler = &proc_dointvec,
758 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
760 .ctl_name = KERN_SPIN_RETRY,
761 .procname = "spin_retry",
763 .maxlen = sizeof (int),
765 .proc_handler = &proc_dointvec,
768 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
770 .procname = "acpi_video_flags",
771 .data = &acpi_realmode_flags,
772 .maxlen = sizeof (unsigned long),
774 .proc_handler = &proc_doulongvec_minmax,
779 .ctl_name = KERN_IA64_UNALIGNED,
780 .procname = "ignore-unaligned-usertrap",
781 .data = &no_unaligned_warning,
782 .maxlen = sizeof (int),
784 .proc_handler = &proc_dointvec,
787 .ctl_name = CTL_UNNUMBERED,
788 .procname = "unaligned-dump-stack",
789 .data = &unaligned_dump_stack,
790 .maxlen = sizeof (int),
792 .proc_handler = &proc_dointvec,
795 #ifdef CONFIG_DETECT_SOFTLOCKUP
797 .ctl_name = CTL_UNNUMBERED,
798 .procname = "softlockup_panic",
799 .data = &softlockup_panic,
800 .maxlen = sizeof(int),
802 .proc_handler = &proc_dointvec_minmax,
803 .strategy = &sysctl_intvec,
808 .ctl_name = CTL_UNNUMBERED,
809 .procname = "softlockup_thresh",
810 .data = &softlockup_thresh,
811 .maxlen = sizeof(int),
813 .proc_handler = &proc_dosoftlockup_thresh,
814 .strategy = &sysctl_intvec,
819 #ifdef CONFIG_DETECT_HUNG_TASK
821 .ctl_name = CTL_UNNUMBERED,
822 .procname = "hung_task_panic",
823 .data = &sysctl_hung_task_panic,
824 .maxlen = sizeof(int),
826 .proc_handler = &proc_dointvec_minmax,
827 .strategy = &sysctl_intvec,
832 .ctl_name = CTL_UNNUMBERED,
833 .procname = "hung_task_check_count",
834 .data = &sysctl_hung_task_check_count,
835 .maxlen = sizeof(unsigned long),
837 .proc_handler = &proc_doulongvec_minmax,
838 .strategy = &sysctl_intvec,
841 .ctl_name = CTL_UNNUMBERED,
842 .procname = "hung_task_timeout_secs",
843 .data = &sysctl_hung_task_timeout_secs,
844 .maxlen = sizeof(unsigned long),
846 .proc_handler = &proc_dohung_task_timeout_secs,
847 .strategy = &sysctl_intvec,
850 .ctl_name = CTL_UNNUMBERED,
851 .procname = "hung_task_warnings",
852 .data = &sysctl_hung_task_warnings,
853 .maxlen = sizeof(unsigned long),
855 .proc_handler = &proc_doulongvec_minmax,
856 .strategy = &sysctl_intvec,
861 .ctl_name = KERN_COMPAT_LOG,
862 .procname = "compat-log",
864 .maxlen = sizeof (int),
866 .proc_handler = &proc_dointvec,
869 #ifdef CONFIG_RT_MUTEXES
871 .ctl_name = KERN_MAX_LOCK_DEPTH,
872 .procname = "max_lock_depth",
873 .data = &max_lock_depth,
874 .maxlen = sizeof(int),
876 .proc_handler = &proc_dointvec,
880 .ctl_name = CTL_UNNUMBERED,
881 .procname = "poweroff_cmd",
882 .data = &poweroff_cmd,
883 .maxlen = POWEROFF_CMD_PATH_LEN,
885 .proc_handler = &proc_dostring,
886 .strategy = &sysctl_string,
890 .ctl_name = CTL_UNNUMBERED,
893 .child = key_sysctls,
896 #ifdef CONFIG_RCU_TORTURE_TEST
898 .ctl_name = CTL_UNNUMBERED,
899 .procname = "rcutorture_runnable",
900 .data = &rcutorture_runnable,
901 .maxlen = sizeof(int),
903 .proc_handler = &proc_dointvec,
906 #ifdef CONFIG_SLOW_WORK
908 .ctl_name = CTL_UNNUMBERED,
909 .procname = "slow-work",
911 .child = slow_work_sysctls,
914 #ifdef CONFIG_PERF_COUNTERS
916 .ctl_name = CTL_UNNUMBERED,
917 .procname = "perf_counter_privileged",
918 .data = &sysctl_perf_counter_priv,
919 .maxlen = sizeof(sysctl_perf_counter_priv),
921 .proc_handler = &proc_dointvec,
924 .ctl_name = CTL_UNNUMBERED,
925 .procname = "perf_counter_mlock_kb",
926 .data = &sysctl_perf_counter_mlock,
927 .maxlen = sizeof(sysctl_perf_counter_mlock),
929 .proc_handler = &proc_dointvec,
933 * NOTE: do not add new entries to this table unless you have read
934 * Documentation/sysctl/ctl_unnumbered.txt
939 static struct ctl_table vm_table[] = {
941 .ctl_name = VM_OVERCOMMIT_MEMORY,
942 .procname = "overcommit_memory",
943 .data = &sysctl_overcommit_memory,
944 .maxlen = sizeof(sysctl_overcommit_memory),
946 .proc_handler = &proc_dointvec,
949 .ctl_name = VM_PANIC_ON_OOM,
950 .procname = "panic_on_oom",
951 .data = &sysctl_panic_on_oom,
952 .maxlen = sizeof(sysctl_panic_on_oom),
954 .proc_handler = &proc_dointvec,
957 .ctl_name = CTL_UNNUMBERED,
958 .procname = "oom_kill_allocating_task",
959 .data = &sysctl_oom_kill_allocating_task,
960 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
962 .proc_handler = &proc_dointvec,
965 .ctl_name = CTL_UNNUMBERED,
966 .procname = "oom_dump_tasks",
967 .data = &sysctl_oom_dump_tasks,
968 .maxlen = sizeof(sysctl_oom_dump_tasks),
970 .proc_handler = &proc_dointvec,
973 .ctl_name = VM_OVERCOMMIT_RATIO,
974 .procname = "overcommit_ratio",
975 .data = &sysctl_overcommit_ratio,
976 .maxlen = sizeof(sysctl_overcommit_ratio),
978 .proc_handler = &proc_dointvec,
981 .ctl_name = VM_PAGE_CLUSTER,
982 .procname = "page-cluster",
983 .data = &page_cluster,
984 .maxlen = sizeof(int),
986 .proc_handler = &proc_dointvec,
989 .ctl_name = VM_DIRTY_BACKGROUND,
990 .procname = "dirty_background_ratio",
991 .data = &dirty_background_ratio,
992 .maxlen = sizeof(dirty_background_ratio),
994 .proc_handler = &dirty_background_ratio_handler,
995 .strategy = &sysctl_intvec,
997 .extra2 = &one_hundred,
1000 .ctl_name = CTL_UNNUMBERED,
1001 .procname = "dirty_background_bytes",
1002 .data = &dirty_background_bytes,
1003 .maxlen = sizeof(dirty_background_bytes),
1005 .proc_handler = &dirty_background_bytes_handler,
1006 .strategy = &sysctl_intvec,
1010 .ctl_name = VM_DIRTY_RATIO,
1011 .procname = "dirty_ratio",
1012 .data = &vm_dirty_ratio,
1013 .maxlen = sizeof(vm_dirty_ratio),
1015 .proc_handler = &dirty_ratio_handler,
1016 .strategy = &sysctl_intvec,
1018 .extra2 = &one_hundred,
1021 .ctl_name = CTL_UNNUMBERED,
1022 .procname = "dirty_bytes",
1023 .data = &vm_dirty_bytes,
1024 .maxlen = sizeof(vm_dirty_bytes),
1026 .proc_handler = &dirty_bytes_handler,
1027 .strategy = &sysctl_intvec,
1031 .procname = "dirty_writeback_centisecs",
1032 .data = &dirty_writeback_interval,
1033 .maxlen = sizeof(dirty_writeback_interval),
1035 .proc_handler = &dirty_writeback_centisecs_handler,
1038 .procname = "dirty_expire_centisecs",
1039 .data = &dirty_expire_interval,
1040 .maxlen = sizeof(dirty_expire_interval),
1042 .proc_handler = &proc_dointvec,
1045 .ctl_name = VM_NR_PDFLUSH_THREADS,
1046 .procname = "nr_pdflush_threads",
1047 .data = &nr_pdflush_threads,
1048 .maxlen = sizeof nr_pdflush_threads,
1049 .mode = 0444 /* read-only*/,
1050 .proc_handler = &proc_dointvec,
1053 .ctl_name = CTL_UNNUMBERED,
1054 .procname = "nr_pdflush_threads_min",
1055 .data = &nr_pdflush_threads_min,
1056 .maxlen = sizeof nr_pdflush_threads_min,
1057 .mode = 0644 /* read-write */,
1058 .proc_handler = &proc_dointvec_minmax,
1059 .strategy = &sysctl_intvec,
1061 .extra2 = &nr_pdflush_threads_max,
1064 .ctl_name = CTL_UNNUMBERED,
1065 .procname = "nr_pdflush_threads_max",
1066 .data = &nr_pdflush_threads_max,
1067 .maxlen = sizeof nr_pdflush_threads_max,
1068 .mode = 0644 /* read-write */,
1069 .proc_handler = &proc_dointvec_minmax,
1070 .strategy = &sysctl_intvec,
1071 .extra1 = &nr_pdflush_threads_min,
1072 .extra2 = &one_thousand,
1075 .ctl_name = VM_SWAPPINESS,
1076 .procname = "swappiness",
1077 .data = &vm_swappiness,
1078 .maxlen = sizeof(vm_swappiness),
1080 .proc_handler = &proc_dointvec_minmax,
1081 .strategy = &sysctl_intvec,
1083 .extra2 = &one_hundred,
1085 #ifdef CONFIG_HUGETLB_PAGE
1087 .procname = "nr_hugepages",
1089 .maxlen = sizeof(unsigned long),
1091 .proc_handler = &hugetlb_sysctl_handler,
1092 .extra1 = (void *)&hugetlb_zero,
1093 .extra2 = (void *)&hugetlb_infinity,
1096 .ctl_name = VM_HUGETLB_GROUP,
1097 .procname = "hugetlb_shm_group",
1098 .data = &sysctl_hugetlb_shm_group,
1099 .maxlen = sizeof(gid_t),
1101 .proc_handler = &proc_dointvec,
1104 .ctl_name = CTL_UNNUMBERED,
1105 .procname = "hugepages_treat_as_movable",
1106 .data = &hugepages_treat_as_movable,
1107 .maxlen = sizeof(int),
1109 .proc_handler = &hugetlb_treat_movable_handler,
1112 .ctl_name = CTL_UNNUMBERED,
1113 .procname = "nr_overcommit_hugepages",
1115 .maxlen = sizeof(unsigned long),
1117 .proc_handler = &hugetlb_overcommit_handler,
1118 .extra1 = (void *)&hugetlb_zero,
1119 .extra2 = (void *)&hugetlb_infinity,
1123 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
1124 .procname = "lowmem_reserve_ratio",
1125 .data = &sysctl_lowmem_reserve_ratio,
1126 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1128 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
1129 .strategy = &sysctl_intvec,
1132 .ctl_name = VM_DROP_PAGECACHE,
1133 .procname = "drop_caches",
1134 .data = &sysctl_drop_caches,
1135 .maxlen = sizeof(int),
1137 .proc_handler = drop_caches_sysctl_handler,
1138 .strategy = &sysctl_intvec,
1141 .ctl_name = VM_MIN_FREE_KBYTES,
1142 .procname = "min_free_kbytes",
1143 .data = &min_free_kbytes,
1144 .maxlen = sizeof(min_free_kbytes),
1146 .proc_handler = &min_free_kbytes_sysctl_handler,
1147 .strategy = &sysctl_intvec,
1151 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
1152 .procname = "percpu_pagelist_fraction",
1153 .data = &percpu_pagelist_fraction,
1154 .maxlen = sizeof(percpu_pagelist_fraction),
1156 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
1157 .strategy = &sysctl_intvec,
1158 .extra1 = &min_percpu_pagelist_fract,
1162 .ctl_name = VM_MAX_MAP_COUNT,
1163 .procname = "max_map_count",
1164 .data = &sysctl_max_map_count,
1165 .maxlen = sizeof(sysctl_max_map_count),
1167 .proc_handler = &proc_dointvec
1171 .ctl_name = CTL_UNNUMBERED,
1172 .procname = "nr_trim_pages",
1173 .data = &sysctl_nr_trim_pages,
1174 .maxlen = sizeof(sysctl_nr_trim_pages),
1176 .proc_handler = &proc_dointvec_minmax,
1177 .strategy = &sysctl_intvec,
1182 .ctl_name = VM_LAPTOP_MODE,
1183 .procname = "laptop_mode",
1184 .data = &laptop_mode,
1185 .maxlen = sizeof(laptop_mode),
1187 .proc_handler = &proc_dointvec_jiffies,
1188 .strategy = &sysctl_jiffies,
1191 .ctl_name = VM_BLOCK_DUMP,
1192 .procname = "block_dump",
1193 .data = &block_dump,
1194 .maxlen = sizeof(block_dump),
1196 .proc_handler = &proc_dointvec,
1197 .strategy = &sysctl_intvec,
1201 .ctl_name = VM_VFS_CACHE_PRESSURE,
1202 .procname = "vfs_cache_pressure",
1203 .data = &sysctl_vfs_cache_pressure,
1204 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1206 .proc_handler = &proc_dointvec,
1207 .strategy = &sysctl_intvec,
1210 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1212 .ctl_name = VM_LEGACY_VA_LAYOUT,
1213 .procname = "legacy_va_layout",
1214 .data = &sysctl_legacy_va_layout,
1215 .maxlen = sizeof(sysctl_legacy_va_layout),
1217 .proc_handler = &proc_dointvec,
1218 .strategy = &sysctl_intvec,
1224 .ctl_name = VM_ZONE_RECLAIM_MODE,
1225 .procname = "zone_reclaim_mode",
1226 .data = &zone_reclaim_mode,
1227 .maxlen = sizeof(zone_reclaim_mode),
1229 .proc_handler = &proc_dointvec,
1230 .strategy = &sysctl_intvec,
1234 .ctl_name = VM_MIN_UNMAPPED,
1235 .procname = "min_unmapped_ratio",
1236 .data = &sysctl_min_unmapped_ratio,
1237 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1239 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1240 .strategy = &sysctl_intvec,
1242 .extra2 = &one_hundred,
1245 .ctl_name = VM_MIN_SLAB,
1246 .procname = "min_slab_ratio",
1247 .data = &sysctl_min_slab_ratio,
1248 .maxlen = sizeof(sysctl_min_slab_ratio),
1250 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1251 .strategy = &sysctl_intvec,
1253 .extra2 = &one_hundred,
1258 .ctl_name = CTL_UNNUMBERED,
1259 .procname = "stat_interval",
1260 .data = &sysctl_stat_interval,
1261 .maxlen = sizeof(sysctl_stat_interval),
1263 .proc_handler = &proc_dointvec_jiffies,
1264 .strategy = &sysctl_jiffies,
1267 #ifdef CONFIG_SECURITY
1269 .ctl_name = CTL_UNNUMBERED,
1270 .procname = "mmap_min_addr",
1271 .data = &mmap_min_addr,
1272 .maxlen = sizeof(unsigned long),
1274 .proc_handler = &proc_doulongvec_minmax,
1279 .ctl_name = CTL_UNNUMBERED,
1280 .procname = "numa_zonelist_order",
1281 .data = &numa_zonelist_order,
1282 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1284 .proc_handler = &numa_zonelist_order_handler,
1285 .strategy = &sysctl_string,
1288 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1289 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1291 .ctl_name = VM_VDSO_ENABLED,
1292 .procname = "vdso_enabled",
1293 .data = &vdso_enabled,
1294 .maxlen = sizeof(vdso_enabled),
1296 .proc_handler = &proc_dointvec,
1297 .strategy = &sysctl_intvec,
1301 #ifdef CONFIG_HIGHMEM
1303 .ctl_name = CTL_UNNUMBERED,
1304 .procname = "highmem_is_dirtyable",
1305 .data = &vm_highmem_is_dirtyable,
1306 .maxlen = sizeof(vm_highmem_is_dirtyable),
1308 .proc_handler = &proc_dointvec_minmax,
1309 .strategy = &sysctl_intvec,
1314 #ifdef CONFIG_UNEVICTABLE_LRU
1316 .ctl_name = CTL_UNNUMBERED,
1317 .procname = "scan_unevictable_pages",
1318 .data = &scan_unevictable_pages,
1319 .maxlen = sizeof(scan_unevictable_pages),
1321 .proc_handler = &scan_unevictable_handler,
1325 * NOTE: do not add new entries to this table unless you have read
1326 * Documentation/sysctl/ctl_unnumbered.txt
1331 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1332 static struct ctl_table binfmt_misc_table[] = {
1337 static struct ctl_table fs_table[] = {
1339 .ctl_name = FS_NRINODE,
1340 .procname = "inode-nr",
1341 .data = &inodes_stat,
1342 .maxlen = 2*sizeof(int),
1344 .proc_handler = &proc_dointvec,
1347 .ctl_name = FS_STATINODE,
1348 .procname = "inode-state",
1349 .data = &inodes_stat,
1350 .maxlen = 7*sizeof(int),
1352 .proc_handler = &proc_dointvec,
1355 .procname = "file-nr",
1356 .data = &files_stat,
1357 .maxlen = 3*sizeof(int),
1359 .proc_handler = &proc_nr_files,
1362 .ctl_name = FS_MAXFILE,
1363 .procname = "file-max",
1364 .data = &files_stat.max_files,
1365 .maxlen = sizeof(int),
1367 .proc_handler = &proc_dointvec,
1370 .ctl_name = CTL_UNNUMBERED,
1371 .procname = "nr_open",
1372 .data = &sysctl_nr_open,
1373 .maxlen = sizeof(int),
1375 .proc_handler = &proc_dointvec_minmax,
1376 .extra1 = &sysctl_nr_open_min,
1377 .extra2 = &sysctl_nr_open_max,
1380 .ctl_name = FS_DENTRY,
1381 .procname = "dentry-state",
1382 .data = &dentry_stat,
1383 .maxlen = 6*sizeof(int),
1385 .proc_handler = &proc_dointvec,
1388 .ctl_name = FS_OVERFLOWUID,
1389 .procname = "overflowuid",
1390 .data = &fs_overflowuid,
1391 .maxlen = sizeof(int),
1393 .proc_handler = &proc_dointvec_minmax,
1394 .strategy = &sysctl_intvec,
1395 .extra1 = &minolduid,
1396 .extra2 = &maxolduid,
1399 .ctl_name = FS_OVERFLOWGID,
1400 .procname = "overflowgid",
1401 .data = &fs_overflowgid,
1402 .maxlen = sizeof(int),
1404 .proc_handler = &proc_dointvec_minmax,
1405 .strategy = &sysctl_intvec,
1406 .extra1 = &minolduid,
1407 .extra2 = &maxolduid,
1409 #ifdef CONFIG_FILE_LOCKING
1411 .ctl_name = FS_LEASES,
1412 .procname = "leases-enable",
1413 .data = &leases_enable,
1414 .maxlen = sizeof(int),
1416 .proc_handler = &proc_dointvec,
1419 #ifdef CONFIG_DNOTIFY
1421 .ctl_name = FS_DIR_NOTIFY,
1422 .procname = "dir-notify-enable",
1423 .data = &dir_notify_enable,
1424 .maxlen = sizeof(int),
1426 .proc_handler = &proc_dointvec,
1430 #ifdef CONFIG_FILE_LOCKING
1432 .ctl_name = FS_LEASE_TIME,
1433 .procname = "lease-break-time",
1434 .data = &lease_break_time,
1435 .maxlen = sizeof(int),
1437 .proc_handler = &proc_dointvec,
1442 .procname = "aio-nr",
1444 .maxlen = sizeof(aio_nr),
1446 .proc_handler = &proc_doulongvec_minmax,
1449 .procname = "aio-max-nr",
1450 .data = &aio_max_nr,
1451 .maxlen = sizeof(aio_max_nr),
1453 .proc_handler = &proc_doulongvec_minmax,
1455 #endif /* CONFIG_AIO */
1456 #ifdef CONFIG_INOTIFY_USER
1458 .ctl_name = FS_INOTIFY,
1459 .procname = "inotify",
1461 .child = inotify_table,
1466 .procname = "epoll",
1468 .child = epoll_table,
1473 .ctl_name = KERN_SETUID_DUMPABLE,
1474 .procname = "suid_dumpable",
1475 .data = &suid_dumpable,
1476 .maxlen = sizeof(int),
1478 .proc_handler = &proc_dointvec_minmax,
1479 .strategy = &sysctl_intvec,
1483 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1485 .ctl_name = CTL_UNNUMBERED,
1486 .procname = "binfmt_misc",
1488 .child = binfmt_misc_table,
1492 * NOTE: do not add new entries to this table unless you have read
1493 * Documentation/sysctl/ctl_unnumbered.txt
1498 static struct ctl_table debug_table[] = {
1499 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1501 .ctl_name = CTL_UNNUMBERED,
1502 .procname = "exception-trace",
1503 .data = &show_unhandled_signals,
1504 .maxlen = sizeof(int),
1506 .proc_handler = proc_dointvec
1512 static struct ctl_table dev_table[] = {
1516 static DEFINE_SPINLOCK(sysctl_lock);
1518 /* called under sysctl_lock */
1519 static int use_table(struct ctl_table_header *p)
1521 if (unlikely(p->unregistering))
1527 /* called under sysctl_lock */
1528 static void unuse_table(struct ctl_table_header *p)
1531 if (unlikely(p->unregistering))
1532 complete(p->unregistering);
1535 /* called under sysctl_lock, will reacquire if has to wait */
1536 static void start_unregistering(struct ctl_table_header *p)
1539 * if p->used is 0, nobody will ever touch that entry again;
1540 * we'll eliminate all paths to it before dropping sysctl_lock
1542 if (unlikely(p->used)) {
1543 struct completion wait;
1544 init_completion(&wait);
1545 p->unregistering = &wait;
1546 spin_unlock(&sysctl_lock);
1547 wait_for_completion(&wait);
1548 spin_lock(&sysctl_lock);
1550 /* anything non-NULL; we'll never dereference it */
1551 p->unregistering = ERR_PTR(-EINVAL);
1554 * do not remove from the list until nobody holds it; walking the
1555 * list in do_sysctl() relies on that.
1557 list_del_init(&p->ctl_entry);
1560 void sysctl_head_get(struct ctl_table_header *head)
1562 spin_lock(&sysctl_lock);
1564 spin_unlock(&sysctl_lock);
1567 void sysctl_head_put(struct ctl_table_header *head)
1569 spin_lock(&sysctl_lock);
1572 spin_unlock(&sysctl_lock);
1575 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1579 spin_lock(&sysctl_lock);
1580 if (!use_table(head))
1581 head = ERR_PTR(-ENOENT);
1582 spin_unlock(&sysctl_lock);
1586 void sysctl_head_finish(struct ctl_table_header *head)
1590 spin_lock(&sysctl_lock);
1592 spin_unlock(&sysctl_lock);
1595 static struct ctl_table_set *
1596 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1598 struct ctl_table_set *set = &root->default_set;
1600 set = root->lookup(root, namespaces);
1604 static struct list_head *
1605 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1607 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1611 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1612 struct ctl_table_header *prev)
1614 struct ctl_table_root *root;
1615 struct list_head *header_list;
1616 struct ctl_table_header *head;
1617 struct list_head *tmp;
1619 spin_lock(&sysctl_lock);
1622 tmp = &prev->ctl_entry;
1626 tmp = &root_table_header.ctl_entry;
1628 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1630 if (!use_table(head))
1632 spin_unlock(&sysctl_lock);
1637 header_list = lookup_header_list(root, namespaces);
1638 if (tmp != header_list)
1642 root = list_entry(root->root_list.next,
1643 struct ctl_table_root, root_list);
1644 if (root == &sysctl_table_root)
1646 header_list = lookup_header_list(root, namespaces);
1647 } while (list_empty(header_list));
1648 tmp = header_list->next;
1651 spin_unlock(&sysctl_lock);
1655 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1657 return __sysctl_head_next(current->nsproxy, prev);
1660 void register_sysctl_root(struct ctl_table_root *root)
1662 spin_lock(&sysctl_lock);
1663 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1664 spin_unlock(&sysctl_lock);
1667 #ifdef CONFIG_SYSCTL_SYSCALL
1668 /* Perform the actual read/write of a sysctl table entry. */
1669 static int do_sysctl_strategy(struct ctl_table_root *root,
1670 struct ctl_table *table,
1671 void __user *oldval, size_t __user *oldlenp,
1672 void __user *newval, size_t newlen)
1680 if (sysctl_perm(root, table, op))
1683 if (table->strategy) {
1684 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1691 /* If there is no strategy routine, or if the strategy returns
1692 * zero, proceed with automatic r/w */
1693 if (table->data && table->maxlen) {
1694 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1701 static int parse_table(int __user *name, int nlen,
1702 void __user *oldval, size_t __user *oldlenp,
1703 void __user *newval, size_t newlen,
1704 struct ctl_table_root *root,
1705 struct ctl_table *table)
1711 if (get_user(n, name))
1713 for ( ; table->ctl_name || table->procname; table++) {
1714 if (!table->ctl_name)
1716 if (n == table->ctl_name) {
1719 if (sysctl_perm(root, table, MAY_EXEC))
1723 table = table->child;
1726 error = do_sysctl_strategy(root, table,
1735 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1736 void __user *newval, size_t newlen)
1738 struct ctl_table_header *head;
1739 int error = -ENOTDIR;
1741 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1745 if (!oldlenp || get_user(old_len, oldlenp))
1749 for (head = sysctl_head_next(NULL); head;
1750 head = sysctl_head_next(head)) {
1751 error = parse_table(name, nlen, oldval, oldlenp,
1753 head->root, head->ctl_table);
1754 if (error != -ENOTDIR) {
1755 sysctl_head_finish(head);
1762 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1764 struct __sysctl_args tmp;
1767 if (copy_from_user(&tmp, args, sizeof(tmp)))
1770 error = deprecated_sysctl_warning(&tmp);
1775 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1776 tmp.newval, tmp.newlen);
1781 #endif /* CONFIG_SYSCTL_SYSCALL */
1784 * sysctl_perm does NOT grant the superuser all rights automatically, because
1785 * some sysctl variables are readonly even to root.
1788 static int test_perm(int mode, int op)
1790 if (!current_euid())
1792 else if (in_egroup_p(0))
1794 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1799 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1804 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1808 if (root->permissions)
1809 mode = root->permissions(root, current->nsproxy, table);
1813 return test_perm(mode, op);
1816 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1818 for (; table->ctl_name || table->procname; table++) {
1819 table->parent = parent;
1821 sysctl_set_parent(table, table->child);
1825 static __init int sysctl_init(void)
1827 sysctl_set_parent(NULL, root_table);
1828 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1831 err = sysctl_check_table(current->nsproxy, root_table);
1837 core_initcall(sysctl_init);
1839 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1840 struct ctl_table *table)
1842 struct ctl_table *p;
1843 const char *s = branch->procname;
1845 /* branch should have named subdirectory as its first element */
1846 if (!s || !branch->child)
1849 /* ... and nothing else */
1850 if (branch[1].procname || branch[1].ctl_name)
1853 /* table should contain subdirectory with the same name */
1854 for (p = table; p->procname || p->ctl_name; p++) {
1857 if (p->procname && strcmp(p->procname, s) == 0)
1863 /* see if attaching q to p would be an improvement */
1864 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1866 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1867 struct ctl_table *next;
1869 int not_in_parent = !p->attached_by;
1871 while ((next = is_branch_in(by, to)) != NULL) {
1872 if (by == q->attached_by)
1874 if (to == p->attached_by)
1880 if (is_better && not_in_parent) {
1881 q->attached_by = by;
1882 q->attached_to = to;
1888 * __register_sysctl_paths - register a sysctl hierarchy
1889 * @root: List of sysctl headers to register on
1890 * @namespaces: Data to compute which lists of sysctl entries are visible
1891 * @path: The path to the directory the sysctl table is in.
1892 * @table: the top-level table structure
1894 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1895 * array. A completely 0 filled entry terminates the table.
1897 * The members of the &struct ctl_table structure are used as follows:
1899 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1900 * must be unique within that level of sysctl
1902 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1903 * enter a sysctl file
1905 * data - a pointer to data for use by proc_handler
1907 * maxlen - the maximum size in bytes of the data
1909 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1911 * child - a pointer to the child sysctl table if this entry is a directory, or
1914 * proc_handler - the text handler routine (described below)
1916 * strategy - the strategy routine (described below)
1918 * de - for internal use by the sysctl routines
1920 * extra1, extra2 - extra pointers usable by the proc handler routines
1922 * Leaf nodes in the sysctl tree will be represented by a single file
1923 * under /proc; non-leaf nodes will be represented by directories.
1925 * sysctl(2) can automatically manage read and write requests through
1926 * the sysctl table. The data and maxlen fields of the ctl_table
1927 * struct enable minimal validation of the values being written to be
1928 * performed, and the mode field allows minimal authentication.
1930 * More sophisticated management can be enabled by the provision of a
1931 * strategy routine with the table entry. This will be called before
1932 * any automatic read or write of the data is performed.
1934 * The strategy routine may return
1936 * < 0 - Error occurred (error is passed to user process)
1938 * 0 - OK - proceed with automatic read or write.
1940 * > 0 - OK - read or write has been done by the strategy routine, so
1941 * return immediately.
1943 * There must be a proc_handler routine for any terminal nodes
1944 * mirrored under /proc/sys (non-terminals are handled by a built-in
1945 * directory handler). Several default handlers are available to
1946 * cover common cases -
1948 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1949 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1950 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1952 * It is the handler's job to read the input buffer from user memory
1953 * and process it. The handler should return 0 on success.
1955 * This routine returns %NULL on a failure to register, and a pointer
1956 * to the table header on success.
1958 struct ctl_table_header *__register_sysctl_paths(
1959 struct ctl_table_root *root,
1960 struct nsproxy *namespaces,
1961 const struct ctl_path *path, struct ctl_table *table)
1963 struct ctl_table_header *header;
1964 struct ctl_table *new, **prevp;
1965 unsigned int n, npath;
1966 struct ctl_table_set *set;
1968 /* Count the path components */
1969 for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
1973 * For each path component, allocate a 2-element ctl_table array.
1974 * The first array element will be filled with the sysctl entry
1975 * for this, the second will be the sentinel (ctl_name == 0).
1977 * We allocate everything in one go so that we don't have to
1978 * worry about freeing additional memory in unregister_sysctl_table.
1980 header = kzalloc(sizeof(struct ctl_table_header) +
1981 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1985 new = (struct ctl_table *) (header + 1);
1987 /* Now connect the dots */
1988 prevp = &header->ctl_table;
1989 for (n = 0; n < npath; ++n, ++path) {
1990 /* Copy the procname */
1991 new->procname = path->procname;
1992 new->ctl_name = path->ctl_name;
1996 prevp = &new->child;
2001 header->ctl_table_arg = table;
2003 INIT_LIST_HEAD(&header->ctl_entry);
2005 header->unregistering = NULL;
2006 header->root = root;
2007 sysctl_set_parent(NULL, header->ctl_table);
2009 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2010 if (sysctl_check_table(namespaces, header->ctl_table)) {
2015 spin_lock(&sysctl_lock);
2016 header->set = lookup_header_set(root, namespaces);
2017 header->attached_by = header->ctl_table;
2018 header->attached_to = root_table;
2019 header->parent = &root_table_header;
2020 for (set = header->set; set; set = set->parent) {
2021 struct ctl_table_header *p;
2022 list_for_each_entry(p, &set->list, ctl_entry) {
2023 if (p->unregistering)
2025 try_attach(p, header);
2028 header->parent->count++;
2029 list_add_tail(&header->ctl_entry, &header->set->list);
2030 spin_unlock(&sysctl_lock);
2036 * register_sysctl_table_path - register a sysctl table hierarchy
2037 * @path: The path to the directory the sysctl table is in.
2038 * @table: the top-level table structure
2040 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2041 * array. A completely 0 filled entry terminates the table.
2043 * See __register_sysctl_paths for more details.
2045 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2046 struct ctl_table *table)
2048 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2053 * register_sysctl_table - register a sysctl table hierarchy
2054 * @table: the top-level table structure
2056 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2057 * array. A completely 0 filled entry terminates the table.
2059 * See register_sysctl_paths for more details.
2061 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2063 static const struct ctl_path null_path[] = { {} };
2065 return register_sysctl_paths(null_path, table);
2069 * unregister_sysctl_table - unregister a sysctl table hierarchy
2070 * @header: the header returned from register_sysctl_table
2072 * Unregisters the sysctl table and all children. proc entries may not
2073 * actually be removed until they are no longer used by anyone.
2075 void unregister_sysctl_table(struct ctl_table_header * header)
2082 spin_lock(&sysctl_lock);
2083 start_unregistering(header);
2084 if (!--header->parent->count) {
2086 kfree(header->parent);
2088 if (!--header->count)
2090 spin_unlock(&sysctl_lock);
2093 int sysctl_is_seen(struct ctl_table_header *p)
2095 struct ctl_table_set *set = p->set;
2097 spin_lock(&sysctl_lock);
2098 if (p->unregistering)
2100 else if (!set->is_seen)
2103 res = set->is_seen(set);
2104 spin_unlock(&sysctl_lock);
2108 void setup_sysctl_set(struct ctl_table_set *p,
2109 struct ctl_table_set *parent,
2110 int (*is_seen)(struct ctl_table_set *))
2112 INIT_LIST_HEAD(&p->list);
2113 p->parent = parent ? parent : &sysctl_table_root.default_set;
2114 p->is_seen = is_seen;
2117 #else /* !CONFIG_SYSCTL */
2118 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2123 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2124 struct ctl_table *table)
2129 void unregister_sysctl_table(struct ctl_table_header * table)
2133 void setup_sysctl_set(struct ctl_table_set *p,
2134 struct ctl_table_set *parent,
2135 int (*is_seen)(struct ctl_table_set *))
2139 void sysctl_head_put(struct ctl_table_header *head)
2143 #endif /* CONFIG_SYSCTL */
2149 #ifdef CONFIG_PROC_SYSCTL
2151 static int _proc_do_string(void* data, int maxlen, int write,
2152 struct file *filp, void __user *buffer,
2153 size_t *lenp, loff_t *ppos)
2159 if (!data || !maxlen || !*lenp) {
2167 while (len < *lenp) {
2168 if (get_user(c, p++))
2170 if (c == 0 || c == '\n')
2176 if(copy_from_user(data, buffer, len))
2178 ((char *) data)[len] = 0;
2196 if(copy_to_user(buffer, data, len))
2199 if(put_user('\n', ((char __user *) buffer) + len))
2210 * proc_dostring - read a string sysctl
2211 * @table: the sysctl table
2212 * @write: %TRUE if this is a write to the sysctl file
2213 * @filp: the file structure
2214 * @buffer: the user buffer
2215 * @lenp: the size of the user buffer
2216 * @ppos: file position
2218 * Reads/writes a string from/to the user buffer. If the kernel
2219 * buffer provided is not large enough to hold the string, the
2220 * string is truncated. The copied string is %NULL-terminated.
2221 * If the string is being read by the user process, it is copied
2222 * and a newline '\n' is added. It is truncated if the buffer is
2225 * Returns 0 on success.
2227 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2228 void __user *buffer, size_t *lenp, loff_t *ppos)
2230 return _proc_do_string(table->data, table->maxlen, write, filp,
2231 buffer, lenp, ppos);
2235 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2237 int write, void *data)
2240 *valp = *negp ? -*lvalp : *lvalp;
2245 *lvalp = (unsigned long)-val;
2248 *lvalp = (unsigned long)val;
2254 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2255 int write, struct file *filp, void __user *buffer,
2256 size_t *lenp, loff_t *ppos,
2257 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2258 int write, void *data),
2261 #define TMPBUFLEN 21
2262 int *i, vleft, first=1, neg, val;
2266 char buf[TMPBUFLEN], *p;
2267 char __user *s = buffer;
2269 if (!tbl_data || !table->maxlen || !*lenp ||
2270 (*ppos && !write)) {
2275 i = (int *) tbl_data;
2276 vleft = table->maxlen / sizeof(*i);
2280 conv = do_proc_dointvec_conv;
2282 for (; left && vleft--; i++, first=0) {
2297 if (len > sizeof(buf) - 1)
2298 len = sizeof(buf) - 1;
2299 if (copy_from_user(buf, s, len))
2303 if (*p == '-' && left > 1) {
2307 if (*p < '0' || *p > '9')
2310 lval = simple_strtoul(p, &p, 0);
2313 if ((len < left) && *p && !isspace(*p))
2320 if (conv(&neg, &lval, i, 1, data))
2327 if (conv(&neg, &lval, i, 0, data))
2330 sprintf(p, "%s%lu", neg ? "-" : "", lval);
2334 if(copy_to_user(s, buf, len))
2341 if (!write && !first && left) {
2342 if(put_user('\n', s))
2349 if (get_user(c, s++))
2364 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2365 void __user *buffer, size_t *lenp, loff_t *ppos,
2366 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2367 int write, void *data),
2370 return __do_proc_dointvec(table->data, table, write, filp,
2371 buffer, lenp, ppos, conv, data);
2375 * proc_dointvec - read a vector of integers
2376 * @table: the sysctl table
2377 * @write: %TRUE if this is a write to the sysctl file
2378 * @filp: the file structure
2379 * @buffer: the user buffer
2380 * @lenp: the size of the user buffer
2381 * @ppos: file position
2383 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2384 * values from/to the user buffer, treated as an ASCII string.
2386 * Returns 0 on success.
2388 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2389 void __user *buffer, size_t *lenp, loff_t *ppos)
2391 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2396 * Taint values can only be increased
2397 * This means we can safely use a temporary.
2399 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2400 void __user *buffer, size_t *lenp, loff_t *ppos)
2403 unsigned long tmptaint = get_taint();
2406 if (write && !capable(CAP_SYS_ADMIN))
2411 err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2417 * Poor man's atomic or. Not worth adding a primitive
2418 * to everyone's atomic.h for this
2421 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2422 if ((tmptaint >> i) & 1)
2430 struct do_proc_dointvec_minmax_conv_param {
2435 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2437 int write, void *data)
2439 struct do_proc_dointvec_minmax_conv_param *param = data;
2441 int val = *negp ? -*lvalp : *lvalp;
2442 if ((param->min && *param->min > val) ||
2443 (param->max && *param->max < val))
2450 *lvalp = (unsigned long)-val;
2453 *lvalp = (unsigned long)val;
2460 * proc_dointvec_minmax - read a vector of integers with min/max values
2461 * @table: the sysctl table
2462 * @write: %TRUE if this is a write to the sysctl file
2463 * @filp: the file structure
2464 * @buffer: the user buffer
2465 * @lenp: the size of the user buffer
2466 * @ppos: file position
2468 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2469 * values from/to the user buffer, treated as an ASCII string.
2471 * This routine will ensure the values are within the range specified by
2472 * table->extra1 (min) and table->extra2 (max).
2474 * Returns 0 on success.
2476 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2477 void __user *buffer, size_t *lenp, loff_t *ppos)
2479 struct do_proc_dointvec_minmax_conv_param param = {
2480 .min = (int *) table->extra1,
2481 .max = (int *) table->extra2,
2483 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2484 do_proc_dointvec_minmax_conv, ¶m);
2487 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2489 void __user *buffer,
2490 size_t *lenp, loff_t *ppos,
2491 unsigned long convmul,
2492 unsigned long convdiv)
2494 #define TMPBUFLEN 21
2495 unsigned long *i, *min, *max, val;
2496 int vleft, first=1, neg;
2498 char buf[TMPBUFLEN], *p;
2499 char __user *s = buffer;
2501 if (!data || !table->maxlen || !*lenp ||
2502 (*ppos && !write)) {
2507 i = (unsigned long *) data;
2508 min = (unsigned long *) table->extra1;
2509 max = (unsigned long *) table->extra2;
2510 vleft = table->maxlen / sizeof(unsigned long);
2513 for (; left && vleft--; i++, min++, max++, first=0) {
2528 if (len > TMPBUFLEN-1)
2530 if (copy_from_user(buf, s, len))
2534 if (*p == '-' && left > 1) {
2538 if (*p < '0' || *p > '9')
2540 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2542 if ((len < left) && *p && !isspace(*p))
2551 if ((min && val < *min) || (max && val > *max))
2558 sprintf(p, "%lu", convdiv * (*i) / convmul);
2562 if(copy_to_user(s, buf, len))
2569 if (!write && !first && left) {
2570 if(put_user('\n', s))
2577 if (get_user(c, s++))
2592 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2594 void __user *buffer,
2595 size_t *lenp, loff_t *ppos,
2596 unsigned long convmul,
2597 unsigned long convdiv)
2599 return __do_proc_doulongvec_minmax(table->data, table, write,
2600 filp, buffer, lenp, ppos, convmul, convdiv);
2604 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2605 * @table: the sysctl table
2606 * @write: %TRUE if this is a write to the sysctl file
2607 * @filp: the file structure
2608 * @buffer: the user buffer
2609 * @lenp: the size of the user buffer
2610 * @ppos: file position
2612 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2613 * values from/to the user buffer, treated as an ASCII string.
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_minmax(struct ctl_table *table, int write, struct file *filp,
2621 void __user *buffer, size_t *lenp, loff_t *ppos)
2623 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2627 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2628 * @table: the sysctl table
2629 * @write: %TRUE if this is a write to the sysctl file
2630 * @filp: the file structure
2631 * @buffer: the user buffer
2632 * @lenp: the size of the user buffer
2633 * @ppos: file position
2635 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2636 * values from/to the user buffer, treated as an ASCII string. The values
2637 * are treated as milliseconds, and converted to jiffies when they are stored.
2639 * This routine will ensure the values are within the range specified by
2640 * table->extra1 (min) and table->extra2 (max).
2642 * Returns 0 on success.
2644 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2646 void __user *buffer,
2647 size_t *lenp, loff_t *ppos)
2649 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2650 lenp, ppos, HZ, 1000l);
2654 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2656 int write, void *data)
2659 if (*lvalp > LONG_MAX / HZ)
2661 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2667 lval = (unsigned long)-val;
2670 lval = (unsigned long)val;
2677 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2679 int write, void *data)
2682 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2684 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2690 lval = (unsigned long)-val;
2693 lval = (unsigned long)val;
2695 *lvalp = jiffies_to_clock_t(lval);
2700 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2702 int write, void *data)
2705 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2711 lval = (unsigned long)-val;
2714 lval = (unsigned long)val;
2716 *lvalp = jiffies_to_msecs(lval);
2722 * proc_dointvec_jiffies - read a vector of integers as seconds
2723 * @table: the sysctl table
2724 * @write: %TRUE if this is a write to the sysctl file
2725 * @filp: the file structure
2726 * @buffer: the user buffer
2727 * @lenp: the size of the user buffer
2728 * @ppos: file position
2730 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2731 * values from/to the user buffer, treated as an ASCII string.
2732 * The values read are assumed to be in seconds, and are converted into
2735 * Returns 0 on success.
2737 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2738 void __user *buffer, size_t *lenp, loff_t *ppos)
2740 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2741 do_proc_dointvec_jiffies_conv,NULL);
2745 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2746 * @table: the sysctl table
2747 * @write: %TRUE if this is a write to the sysctl file
2748 * @filp: the file structure
2749 * @buffer: the user buffer
2750 * @lenp: the size of the user buffer
2751 * @ppos: pointer to the file position
2753 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2754 * values from/to the user buffer, treated as an ASCII string.
2755 * The values read are assumed to be in 1/USER_HZ seconds, and
2756 * are converted into jiffies.
2758 * Returns 0 on success.
2760 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2761 void __user *buffer, size_t *lenp, loff_t *ppos)
2763 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2764 do_proc_dointvec_userhz_jiffies_conv,NULL);
2768 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2769 * @table: the sysctl table
2770 * @write: %TRUE if this is a write to the sysctl file
2771 * @filp: the file structure
2772 * @buffer: the user buffer
2773 * @lenp: the size of the user buffer
2774 * @ppos: file position
2775 * @ppos: the current position in the file
2777 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2778 * values from/to the user buffer, treated as an ASCII string.
2779 * The values read are assumed to be in 1/1000 seconds, and
2780 * are converted into jiffies.
2782 * Returns 0 on success.
2784 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2785 void __user *buffer, size_t *lenp, loff_t *ppos)
2787 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2788 do_proc_dointvec_ms_jiffies_conv, NULL);
2791 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2792 void __user *buffer, size_t *lenp, loff_t *ppos)
2794 struct pid *new_pid;
2798 tmp = pid_vnr(cad_pid);
2800 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2801 lenp, ppos, NULL, NULL);
2805 new_pid = find_get_pid(tmp);
2809 put_pid(xchg(&cad_pid, new_pid));
2813 #else /* CONFIG_PROC_FS */
2815 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2816 void __user *buffer, size_t *lenp, loff_t *ppos)
2821 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2822 void __user *buffer, size_t *lenp, loff_t *ppos)
2827 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2828 void __user *buffer, size_t *lenp, loff_t *ppos)
2833 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2834 void __user *buffer, size_t *lenp, loff_t *ppos)
2839 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2840 void __user *buffer, size_t *lenp, loff_t *ppos)
2845 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2846 void __user *buffer, size_t *lenp, loff_t *ppos)
2851 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2852 void __user *buffer, size_t *lenp, loff_t *ppos)
2857 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2859 void __user *buffer,
2860 size_t *lenp, loff_t *ppos)
2866 #endif /* CONFIG_PROC_FS */
2869 #ifdef CONFIG_SYSCTL_SYSCALL
2871 * General sysctl support routines
2874 /* The generic sysctl data routine (used if no strategy routine supplied) */
2875 int sysctl_data(struct ctl_table *table,
2876 void __user *oldval, size_t __user *oldlenp,
2877 void __user *newval, size_t newlen)
2881 /* Get out of I don't have a variable */
2882 if (!table->data || !table->maxlen)
2885 if (oldval && oldlenp) {
2886 if (get_user(len, oldlenp))
2889 if (len > table->maxlen)
2890 len = table->maxlen;
2891 if (copy_to_user(oldval, table->data, len))
2893 if (put_user(len, oldlenp))
2898 if (newval && newlen) {
2899 if (newlen > table->maxlen)
2900 newlen = table->maxlen;
2902 if (copy_from_user(table->data, newval, newlen))
2908 /* The generic string strategy routine: */
2909 int sysctl_string(struct ctl_table *table,
2910 void __user *oldval, size_t __user *oldlenp,
2911 void __user *newval, size_t newlen)
2913 if (!table->data || !table->maxlen)
2916 if (oldval && oldlenp) {
2918 if (get_user(bufsize, oldlenp))
2921 size_t len = strlen(table->data), copied;
2923 /* This shouldn't trigger for a well-formed sysctl */
2924 if (len > table->maxlen)
2925 len = table->maxlen;
2927 /* Copy up to a max of bufsize-1 bytes of the string */
2928 copied = (len >= bufsize) ? bufsize - 1 : len;
2930 if (copy_to_user(oldval, table->data, copied) ||
2931 put_user(0, (char __user *)(oldval + copied)))
2933 if (put_user(len, oldlenp))
2937 if (newval && newlen) {
2938 size_t len = newlen;
2939 if (len > table->maxlen)
2940 len = table->maxlen;
2941 if(copy_from_user(table->data, newval, len))
2943 if (len == table->maxlen)
2945 ((char *) table->data)[len] = 0;
2951 * This function makes sure that all of the integers in the vector
2952 * are between the minimum and maximum values given in the arrays
2953 * table->extra1 and table->extra2, respectively.
2955 int sysctl_intvec(struct ctl_table *table,
2956 void __user *oldval, size_t __user *oldlenp,
2957 void __user *newval, size_t newlen)
2960 if (newval && newlen) {
2961 int __user *vec = (int __user *) newval;
2962 int *min = (int *) table->extra1;
2963 int *max = (int *) table->extra2;
2967 if (newlen % sizeof(int) != 0)
2970 if (!table->extra1 && !table->extra2)
2973 if (newlen > table->maxlen)
2974 newlen = table->maxlen;
2975 length = newlen / sizeof(int);
2977 for (i = 0; i < length; i++) {
2979 if (get_user(value, vec + i))
2981 if (min && value < min[i])
2983 if (max && value > max[i])
2990 /* Strategy function to convert jiffies to seconds */
2991 int sysctl_jiffies(struct ctl_table *table,
2992 void __user *oldval, size_t __user *oldlenp,
2993 void __user *newval, size_t newlen)
2995 if (oldval && oldlenp) {
2998 if (get_user(olen, oldlenp))
3003 if (olen < sizeof(int))
3006 val = *(int *)(table->data) / HZ;
3007 if (put_user(val, (int __user *)oldval))
3009 if (put_user(sizeof(int), oldlenp))
3013 if (newval && newlen) {
3015 if (newlen != sizeof(int))
3017 if (get_user(new, (int __user *)newval))
3019 *(int *)(table->data) = new*HZ;
3024 /* Strategy function to convert jiffies to seconds */
3025 int sysctl_ms_jiffies(struct ctl_table *table,
3026 void __user *oldval, size_t __user *oldlenp,
3027 void __user *newval, size_t newlen)
3029 if (oldval && oldlenp) {
3032 if (get_user(olen, oldlenp))
3037 if (olen < sizeof(int))
3040 val = jiffies_to_msecs(*(int *)(table->data));
3041 if (put_user(val, (int __user *)oldval))
3043 if (put_user(sizeof(int), oldlenp))
3047 if (newval && newlen) {
3049 if (newlen != sizeof(int))
3051 if (get_user(new, (int __user *)newval))
3053 *(int *)(table->data) = msecs_to_jiffies(new);
3060 #else /* CONFIG_SYSCTL_SYSCALL */
3063 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3065 struct __sysctl_args tmp;
3068 if (copy_from_user(&tmp, args, sizeof(tmp)))
3071 error = deprecated_sysctl_warning(&tmp);
3073 /* If no error reading the parameters then just -ENOSYS ... */
3080 int sysctl_data(struct ctl_table *table,
3081 void __user *oldval, size_t __user *oldlenp,
3082 void __user *newval, size_t newlen)
3087 int sysctl_string(struct ctl_table *table,
3088 void __user *oldval, size_t __user *oldlenp,
3089 void __user *newval, size_t newlen)
3094 int sysctl_intvec(struct ctl_table *table,
3095 void __user *oldval, size_t __user *oldlenp,
3096 void __user *newval, size_t newlen)
3101 int sysctl_jiffies(struct ctl_table *table,
3102 void __user *oldval, size_t __user *oldlenp,
3103 void __user *newval, size_t newlen)
3108 int sysctl_ms_jiffies(struct ctl_table *table,
3109 void __user *oldval, size_t __user *oldlenp,
3110 void __user *newval, size_t newlen)
3115 #endif /* CONFIG_SYSCTL_SYSCALL */
3117 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3119 static int msg_count;
3120 int name[CTL_MAXNAME];
3123 /* Check args->nlen. */
3124 if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3127 /* Read in the sysctl name for better debug message logging */
3128 for (i = 0; i < args->nlen; i++)
3129 if (get_user(name[i], args->name + i))
3132 /* Ignore accesses to kernel.version */
3133 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3136 if (msg_count < 5) {
3139 "warning: process `%s' used the deprecated sysctl "
3140 "system call with ", current->comm);
3141 for (i = 0; i < args->nlen; i++)
3142 printk("%d.", name[i]);
3149 * No sense putting this after each symbol definition, twice,
3150 * exception granted :-)
3152 EXPORT_SYMBOL(proc_dointvec);
3153 EXPORT_SYMBOL(proc_dointvec_jiffies);
3154 EXPORT_SYMBOL(proc_dointvec_minmax);
3155 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3156 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3157 EXPORT_SYMBOL(proc_dostring);
3158 EXPORT_SYMBOL(proc_doulongvec_minmax);
3159 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3160 EXPORT_SYMBOL(register_sysctl_table);
3161 EXPORT_SYMBOL(register_sysctl_paths);
3162 EXPORT_SYMBOL(sysctl_intvec);
3163 EXPORT_SYMBOL(sysctl_jiffies);
3164 EXPORT_SYMBOL(sysctl_ms_jiffies);
3165 EXPORT_SYMBOL(sysctl_string);
3166 EXPORT_SYMBOL(sysctl_data);
3167 EXPORT_SYMBOL(unregister_sysctl_table);