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/kmemcheck.h>
31 #include <linux/smp_lock.h>
33 #include <linux/init.h>
34 #include <linux/kernel.h>
35 #include <linux/kobject.h>
36 #include <linux/net.h>
37 #include <linux/sysrq.h>
38 #include <linux/highuid.h>
39 #include <linux/writeback.h>
40 #include <linux/hugetlb.h>
41 #include <linux/initrd.h>
42 #include <linux/key.h>
43 #include <linux/times.h>
44 #include <linux/limits.h>
45 #include <linux/dcache.h>
46 #include <linux/syscalls.h>
47 #include <linux/vmstat.h>
48 #include <linux/nfs_fs.h>
49 #include <linux/acpi.h>
50 #include <linux/reboot.h>
51 #include <linux/ftrace.h>
52 #include <linux/slow-work.h>
53 #include <linux/perf_counter.h>
55 #include <asm/uaccess.h>
56 #include <asm/processor.h>
60 #include <asm/stacktrace.h>
64 static int deprecated_sysctl_warning(struct __sysctl_args *args);
66 #if defined(CONFIG_SYSCTL)
68 /* External variables not in a header file. */
70 extern int print_fatal_signals;
71 extern int sysctl_overcommit_memory;
72 extern int sysctl_overcommit_ratio;
73 extern int sysctl_panic_on_oom;
74 extern int sysctl_oom_kill_allocating_task;
75 extern int sysctl_oom_dump_tasks;
76 extern int max_threads;
77 extern int core_uses_pid;
78 extern int suid_dumpable;
79 extern char core_pattern[];
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 /* Constants used for minimum and maximum */
96 #ifdef CONFIG_DETECT_SOFTLOCKUP
97 static int sixty = 60;
98 static int neg_one = -1;
102 static int __maybe_unused one = 1;
103 static int __maybe_unused two = 2;
104 static unsigned long one_ul = 1;
105 static int one_hundred = 100;
107 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
108 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
110 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
111 static int maxolduid = 65535;
112 static int minolduid;
113 static int min_percpu_pagelist_fract = 8;
115 static int ngroups_max = NGROUPS_MAX;
117 #ifdef CONFIG_MODULES
118 extern char modprobe_path[];
119 extern int modules_disabled;
121 #ifdef CONFIG_CHR_DEV_SG
122 extern int sg_big_buff;
126 #include <asm/system.h>
129 #ifdef CONFIG_SPARC64
130 extern int sysctl_tsb_ratio;
134 extern int pwrsw_enabled;
135 extern int unaligned_enabled;
139 #ifdef CONFIG_MATHEMU
140 extern int sysctl_ieee_emulation_warnings;
142 extern int sysctl_userprocess_debug;
143 extern int spin_retry;
146 #ifdef CONFIG_BSD_PROCESS_ACCT
147 extern int acct_parm[];
151 extern int no_unaligned_warning;
152 extern int unaligned_dump_stack;
155 #ifdef CONFIG_RT_MUTEXES
156 extern int max_lock_depth;
159 #ifdef CONFIG_PROC_SYSCTL
160 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
161 void __user *buffer, size_t *lenp, loff_t *ppos);
162 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
163 void __user *buffer, size_t *lenp, loff_t *ppos);
166 static struct ctl_table root_table[];
167 static struct ctl_table_root sysctl_table_root;
168 static struct ctl_table_header root_table_header = {
170 .ctl_table = root_table,
171 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
172 .root = &sysctl_table_root,
173 .set = &sysctl_table_root.default_set,
175 static struct ctl_table_root sysctl_table_root = {
176 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
177 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
180 static struct ctl_table kern_table[];
181 static struct ctl_table vm_table[];
182 static struct ctl_table fs_table[];
183 static struct ctl_table debug_table[];
184 static struct ctl_table dev_table[];
185 extern struct ctl_table random_table[];
186 #ifdef CONFIG_INOTIFY_USER
187 extern struct ctl_table inotify_table[];
190 extern struct ctl_table epoll_table[];
193 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
194 int sysctl_legacy_va_layout;
197 extern int prove_locking;
198 extern int lock_stat;
200 /* The default sysctl tables: */
202 static struct ctl_table root_table[] = {
204 .ctl_name = CTL_KERN,
205 .procname = "kernel",
222 .ctl_name = CTL_DEBUG,
225 .child = debug_table,
234 * NOTE: do not add new entries to this table unless you have read
235 * Documentation/sysctl/ctl_unnumbered.txt
240 #ifdef CONFIG_SCHED_DEBUG
241 static int min_sched_granularity_ns = 100000; /* 100 usecs */
242 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
243 static int min_wakeup_granularity_ns; /* 0 usecs */
244 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
247 static struct ctl_table kern_table[] = {
248 #ifdef CONFIG_SCHED_DEBUG
250 .ctl_name = CTL_UNNUMBERED,
251 .procname = "sched_min_granularity_ns",
252 .data = &sysctl_sched_min_granularity,
253 .maxlen = sizeof(unsigned int),
255 .proc_handler = &sched_nr_latency_handler,
256 .strategy = &sysctl_intvec,
257 .extra1 = &min_sched_granularity_ns,
258 .extra2 = &max_sched_granularity_ns,
261 .ctl_name = CTL_UNNUMBERED,
262 .procname = "sched_latency_ns",
263 .data = &sysctl_sched_latency,
264 .maxlen = sizeof(unsigned int),
266 .proc_handler = &sched_nr_latency_handler,
267 .strategy = &sysctl_intvec,
268 .extra1 = &min_sched_granularity_ns,
269 .extra2 = &max_sched_granularity_ns,
272 .ctl_name = CTL_UNNUMBERED,
273 .procname = "sched_wakeup_granularity_ns",
274 .data = &sysctl_sched_wakeup_granularity,
275 .maxlen = sizeof(unsigned int),
277 .proc_handler = &proc_dointvec_minmax,
278 .strategy = &sysctl_intvec,
279 .extra1 = &min_wakeup_granularity_ns,
280 .extra2 = &max_wakeup_granularity_ns,
283 .ctl_name = CTL_UNNUMBERED,
284 .procname = "sched_shares_ratelimit",
285 .data = &sysctl_sched_shares_ratelimit,
286 .maxlen = sizeof(unsigned int),
288 .proc_handler = &proc_dointvec,
291 .ctl_name = CTL_UNNUMBERED,
292 .procname = "sched_shares_thresh",
293 .data = &sysctl_sched_shares_thresh,
294 .maxlen = sizeof(unsigned int),
296 .proc_handler = &proc_dointvec_minmax,
297 .strategy = &sysctl_intvec,
301 .ctl_name = CTL_UNNUMBERED,
302 .procname = "sched_child_runs_first",
303 .data = &sysctl_sched_child_runs_first,
304 .maxlen = sizeof(unsigned int),
306 .proc_handler = &proc_dointvec,
309 .ctl_name = CTL_UNNUMBERED,
310 .procname = "sched_features",
311 .data = &sysctl_sched_features,
312 .maxlen = sizeof(unsigned int),
314 .proc_handler = &proc_dointvec,
317 .ctl_name = CTL_UNNUMBERED,
318 .procname = "sched_migration_cost",
319 .data = &sysctl_sched_migration_cost,
320 .maxlen = sizeof(unsigned int),
322 .proc_handler = &proc_dointvec,
325 .ctl_name = CTL_UNNUMBERED,
326 .procname = "sched_nr_migrate",
327 .data = &sysctl_sched_nr_migrate,
328 .maxlen = sizeof(unsigned int),
330 .proc_handler = &proc_dointvec,
333 .ctl_name = CTL_UNNUMBERED,
334 .procname = "timer_migration",
335 .data = &sysctl_timer_migration,
336 .maxlen = sizeof(unsigned int),
338 .proc_handler = &proc_dointvec,
342 .ctl_name = CTL_UNNUMBERED,
343 .procname = "sched_rt_period_us",
344 .data = &sysctl_sched_rt_period,
345 .maxlen = sizeof(unsigned int),
347 .proc_handler = &sched_rt_handler,
350 .ctl_name = CTL_UNNUMBERED,
351 .procname = "sched_rt_runtime_us",
352 .data = &sysctl_sched_rt_runtime,
353 .maxlen = sizeof(int),
355 .proc_handler = &sched_rt_handler,
358 .ctl_name = CTL_UNNUMBERED,
359 .procname = "sched_compat_yield",
360 .data = &sysctl_sched_compat_yield,
361 .maxlen = sizeof(unsigned int),
363 .proc_handler = &proc_dointvec,
365 #ifdef CONFIG_PROVE_LOCKING
367 .ctl_name = CTL_UNNUMBERED,
368 .procname = "prove_locking",
369 .data = &prove_locking,
370 .maxlen = sizeof(int),
372 .proc_handler = &proc_dointvec,
375 #ifdef CONFIG_LOCK_STAT
377 .ctl_name = CTL_UNNUMBERED,
378 .procname = "lock_stat",
380 .maxlen = sizeof(int),
382 .proc_handler = &proc_dointvec,
386 .ctl_name = KERN_PANIC,
388 .data = &panic_timeout,
389 .maxlen = sizeof(int),
391 .proc_handler = &proc_dointvec,
394 .ctl_name = KERN_CORE_USES_PID,
395 .procname = "core_uses_pid",
396 .data = &core_uses_pid,
397 .maxlen = sizeof(int),
399 .proc_handler = &proc_dointvec,
402 .ctl_name = KERN_CORE_PATTERN,
403 .procname = "core_pattern",
404 .data = core_pattern,
405 .maxlen = CORENAME_MAX_SIZE,
407 .proc_handler = &proc_dostring,
408 .strategy = &sysctl_string,
410 #ifdef CONFIG_PROC_SYSCTL
412 .procname = "tainted",
413 .maxlen = sizeof(long),
415 .proc_handler = &proc_taint,
418 #ifdef CONFIG_LATENCYTOP
420 .procname = "latencytop",
421 .data = &latencytop_enabled,
422 .maxlen = sizeof(int),
424 .proc_handler = &proc_dointvec,
427 #ifdef CONFIG_BLK_DEV_INITRD
429 .ctl_name = KERN_REALROOTDEV,
430 .procname = "real-root-dev",
431 .data = &real_root_dev,
432 .maxlen = sizeof(int),
434 .proc_handler = &proc_dointvec,
438 .ctl_name = CTL_UNNUMBERED,
439 .procname = "print-fatal-signals",
440 .data = &print_fatal_signals,
441 .maxlen = sizeof(int),
443 .proc_handler = &proc_dointvec,
447 .ctl_name = KERN_SPARC_REBOOT,
448 .procname = "reboot-cmd",
449 .data = reboot_command,
452 .proc_handler = &proc_dostring,
453 .strategy = &sysctl_string,
456 .ctl_name = KERN_SPARC_STOP_A,
457 .procname = "stop-a",
458 .data = &stop_a_enabled,
459 .maxlen = sizeof (int),
461 .proc_handler = &proc_dointvec,
464 .ctl_name = KERN_SPARC_SCONS_PWROFF,
465 .procname = "scons-poweroff",
466 .data = &scons_pwroff,
467 .maxlen = sizeof (int),
469 .proc_handler = &proc_dointvec,
472 #ifdef CONFIG_SPARC64
474 .ctl_name = CTL_UNNUMBERED,
475 .procname = "tsb-ratio",
476 .data = &sysctl_tsb_ratio,
477 .maxlen = sizeof (int),
479 .proc_handler = &proc_dointvec,
484 .ctl_name = KERN_HPPA_PWRSW,
485 .procname = "soft-power",
486 .data = &pwrsw_enabled,
487 .maxlen = sizeof (int),
489 .proc_handler = &proc_dointvec,
492 .ctl_name = KERN_HPPA_UNALIGNED,
493 .procname = "unaligned-trap",
494 .data = &unaligned_enabled,
495 .maxlen = sizeof (int),
497 .proc_handler = &proc_dointvec,
501 .ctl_name = KERN_CTLALTDEL,
502 .procname = "ctrl-alt-del",
504 .maxlen = sizeof(int),
506 .proc_handler = &proc_dointvec,
508 #ifdef CONFIG_FUNCTION_TRACER
510 .ctl_name = CTL_UNNUMBERED,
511 .procname = "ftrace_enabled",
512 .data = &ftrace_enabled,
513 .maxlen = sizeof(int),
515 .proc_handler = &ftrace_enable_sysctl,
518 #ifdef CONFIG_STACK_TRACER
520 .ctl_name = CTL_UNNUMBERED,
521 .procname = "stack_tracer_enabled",
522 .data = &stack_tracer_enabled,
523 .maxlen = sizeof(int),
525 .proc_handler = &stack_trace_sysctl,
528 #ifdef CONFIG_TRACING
530 .ctl_name = CTL_UNNUMBERED,
531 .procname = "ftrace_dump_on_oops",
532 .data = &ftrace_dump_on_oops,
533 .maxlen = sizeof(int),
535 .proc_handler = &proc_dointvec,
538 #ifdef CONFIG_MODULES
540 .ctl_name = KERN_MODPROBE,
541 .procname = "modprobe",
542 .data = &modprobe_path,
543 .maxlen = KMOD_PATH_LEN,
545 .proc_handler = &proc_dostring,
546 .strategy = &sysctl_string,
549 .ctl_name = CTL_UNNUMBERED,
550 .procname = "modules_disabled",
551 .data = &modules_disabled,
552 .maxlen = sizeof(int),
554 /* only handle a transition from default "0" to "1" */
555 .proc_handler = &proc_dointvec_minmax,
560 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
562 .ctl_name = KERN_HOTPLUG,
563 .procname = "hotplug",
564 .data = &uevent_helper,
565 .maxlen = UEVENT_HELPER_PATH_LEN,
567 .proc_handler = &proc_dostring,
568 .strategy = &sysctl_string,
571 #ifdef CONFIG_CHR_DEV_SG
573 .ctl_name = KERN_SG_BIG_BUFF,
574 .procname = "sg-big-buff",
575 .data = &sg_big_buff,
576 .maxlen = sizeof (int),
578 .proc_handler = &proc_dointvec,
581 #ifdef CONFIG_BSD_PROCESS_ACCT
583 .ctl_name = KERN_ACCT,
586 .maxlen = 3*sizeof(int),
588 .proc_handler = &proc_dointvec,
591 #ifdef CONFIG_MAGIC_SYSRQ
593 .ctl_name = KERN_SYSRQ,
595 .data = &__sysrq_enabled,
596 .maxlen = sizeof (int),
598 .proc_handler = &proc_dointvec,
601 #ifdef CONFIG_PROC_SYSCTL
603 .procname = "cad_pid",
605 .maxlen = sizeof (int),
607 .proc_handler = &proc_do_cad_pid,
611 .ctl_name = KERN_MAX_THREADS,
612 .procname = "threads-max",
613 .data = &max_threads,
614 .maxlen = sizeof(int),
616 .proc_handler = &proc_dointvec,
619 .ctl_name = KERN_RANDOM,
620 .procname = "random",
622 .child = random_table,
625 .ctl_name = KERN_OVERFLOWUID,
626 .procname = "overflowuid",
627 .data = &overflowuid,
628 .maxlen = sizeof(int),
630 .proc_handler = &proc_dointvec_minmax,
631 .strategy = &sysctl_intvec,
632 .extra1 = &minolduid,
633 .extra2 = &maxolduid,
636 .ctl_name = KERN_OVERFLOWGID,
637 .procname = "overflowgid",
638 .data = &overflowgid,
639 .maxlen = sizeof(int),
641 .proc_handler = &proc_dointvec_minmax,
642 .strategy = &sysctl_intvec,
643 .extra1 = &minolduid,
644 .extra2 = &maxolduid,
647 #ifdef CONFIG_MATHEMU
649 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
650 .procname = "ieee_emulation_warnings",
651 .data = &sysctl_ieee_emulation_warnings,
652 .maxlen = sizeof(int),
654 .proc_handler = &proc_dointvec,
658 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
659 .procname = "userprocess_debug",
660 .data = &sysctl_userprocess_debug,
661 .maxlen = sizeof(int),
663 .proc_handler = &proc_dointvec,
667 .ctl_name = KERN_PIDMAX,
668 .procname = "pid_max",
670 .maxlen = sizeof (int),
672 .proc_handler = &proc_dointvec_minmax,
673 .strategy = sysctl_intvec,
674 .extra1 = &pid_max_min,
675 .extra2 = &pid_max_max,
678 .ctl_name = KERN_PANIC_ON_OOPS,
679 .procname = "panic_on_oops",
680 .data = &panic_on_oops,
681 .maxlen = sizeof(int),
683 .proc_handler = &proc_dointvec,
685 #if defined CONFIG_PRINTK
687 .ctl_name = KERN_PRINTK,
688 .procname = "printk",
689 .data = &console_loglevel,
690 .maxlen = 4*sizeof(int),
692 .proc_handler = &proc_dointvec,
695 .ctl_name = KERN_PRINTK_RATELIMIT,
696 .procname = "printk_ratelimit",
697 .data = &printk_ratelimit_state.interval,
698 .maxlen = sizeof(int),
700 .proc_handler = &proc_dointvec_jiffies,
701 .strategy = &sysctl_jiffies,
704 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
705 .procname = "printk_ratelimit_burst",
706 .data = &printk_ratelimit_state.burst,
707 .maxlen = sizeof(int),
709 .proc_handler = &proc_dointvec,
713 .ctl_name = KERN_NGROUPS_MAX,
714 .procname = "ngroups_max",
715 .data = &ngroups_max,
716 .maxlen = sizeof (int),
718 .proc_handler = &proc_dointvec,
720 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
722 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
723 .procname = "unknown_nmi_panic",
724 .data = &unknown_nmi_panic,
725 .maxlen = sizeof (int),
727 .proc_handler = &proc_dointvec,
730 .procname = "nmi_watchdog",
731 .data = &nmi_watchdog_enabled,
732 .maxlen = sizeof (int),
734 .proc_handler = &proc_nmi_enabled,
737 #if defined(CONFIG_X86)
739 .ctl_name = KERN_PANIC_ON_NMI,
740 .procname = "panic_on_unrecovered_nmi",
741 .data = &panic_on_unrecovered_nmi,
742 .maxlen = sizeof(int),
744 .proc_handler = &proc_dointvec,
747 .ctl_name = KERN_BOOTLOADER_TYPE,
748 .procname = "bootloader_type",
749 .data = &bootloader_type,
750 .maxlen = sizeof (int),
752 .proc_handler = &proc_dointvec,
755 .ctl_name = CTL_UNNUMBERED,
756 .procname = "bootloader_version",
757 .data = &bootloader_version,
758 .maxlen = sizeof (int),
760 .proc_handler = &proc_dointvec,
763 .ctl_name = CTL_UNNUMBERED,
764 .procname = "kstack_depth_to_print",
765 .data = &kstack_depth_to_print,
766 .maxlen = sizeof(int),
768 .proc_handler = &proc_dointvec,
771 .ctl_name = CTL_UNNUMBERED,
772 .procname = "io_delay_type",
773 .data = &io_delay_type,
774 .maxlen = sizeof(int),
776 .proc_handler = &proc_dointvec,
779 #if defined(CONFIG_MMU)
781 .ctl_name = KERN_RANDOMIZE,
782 .procname = "randomize_va_space",
783 .data = &randomize_va_space,
784 .maxlen = sizeof(int),
786 .proc_handler = &proc_dointvec,
789 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
791 .ctl_name = KERN_SPIN_RETRY,
792 .procname = "spin_retry",
794 .maxlen = sizeof (int),
796 .proc_handler = &proc_dointvec,
799 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
801 .procname = "acpi_video_flags",
802 .data = &acpi_realmode_flags,
803 .maxlen = sizeof (unsigned long),
805 .proc_handler = &proc_doulongvec_minmax,
810 .ctl_name = KERN_IA64_UNALIGNED,
811 .procname = "ignore-unaligned-usertrap",
812 .data = &no_unaligned_warning,
813 .maxlen = sizeof (int),
815 .proc_handler = &proc_dointvec,
818 .ctl_name = CTL_UNNUMBERED,
819 .procname = "unaligned-dump-stack",
820 .data = &unaligned_dump_stack,
821 .maxlen = sizeof (int),
823 .proc_handler = &proc_dointvec,
826 #ifdef CONFIG_DETECT_SOFTLOCKUP
828 .ctl_name = CTL_UNNUMBERED,
829 .procname = "softlockup_panic",
830 .data = &softlockup_panic,
831 .maxlen = sizeof(int),
833 .proc_handler = &proc_dointvec_minmax,
834 .strategy = &sysctl_intvec,
839 .ctl_name = CTL_UNNUMBERED,
840 .procname = "softlockup_thresh",
841 .data = &softlockup_thresh,
842 .maxlen = sizeof(int),
844 .proc_handler = &proc_dosoftlockup_thresh,
845 .strategy = &sysctl_intvec,
850 #ifdef CONFIG_DETECT_HUNG_TASK
852 .ctl_name = CTL_UNNUMBERED,
853 .procname = "hung_task_panic",
854 .data = &sysctl_hung_task_panic,
855 .maxlen = sizeof(int),
857 .proc_handler = &proc_dointvec_minmax,
858 .strategy = &sysctl_intvec,
863 .ctl_name = CTL_UNNUMBERED,
864 .procname = "hung_task_check_count",
865 .data = &sysctl_hung_task_check_count,
866 .maxlen = sizeof(unsigned long),
868 .proc_handler = &proc_doulongvec_minmax,
869 .strategy = &sysctl_intvec,
872 .ctl_name = CTL_UNNUMBERED,
873 .procname = "hung_task_timeout_secs",
874 .data = &sysctl_hung_task_timeout_secs,
875 .maxlen = sizeof(unsigned long),
877 .proc_handler = &proc_dohung_task_timeout_secs,
878 .strategy = &sysctl_intvec,
881 .ctl_name = CTL_UNNUMBERED,
882 .procname = "hung_task_warnings",
883 .data = &sysctl_hung_task_warnings,
884 .maxlen = sizeof(unsigned long),
886 .proc_handler = &proc_doulongvec_minmax,
887 .strategy = &sysctl_intvec,
892 .ctl_name = KERN_COMPAT_LOG,
893 .procname = "compat-log",
895 .maxlen = sizeof (int),
897 .proc_handler = &proc_dointvec,
900 #ifdef CONFIG_RT_MUTEXES
902 .ctl_name = KERN_MAX_LOCK_DEPTH,
903 .procname = "max_lock_depth",
904 .data = &max_lock_depth,
905 .maxlen = sizeof(int),
907 .proc_handler = &proc_dointvec,
911 .ctl_name = CTL_UNNUMBERED,
912 .procname = "poweroff_cmd",
913 .data = &poweroff_cmd,
914 .maxlen = POWEROFF_CMD_PATH_LEN,
916 .proc_handler = &proc_dostring,
917 .strategy = &sysctl_string,
921 .ctl_name = CTL_UNNUMBERED,
924 .child = key_sysctls,
927 #ifdef CONFIG_RCU_TORTURE_TEST
929 .ctl_name = CTL_UNNUMBERED,
930 .procname = "rcutorture_runnable",
931 .data = &rcutorture_runnable,
932 .maxlen = sizeof(int),
934 .proc_handler = &proc_dointvec,
937 #ifdef CONFIG_SLOW_WORK
939 .ctl_name = CTL_UNNUMBERED,
940 .procname = "slow-work",
942 .child = slow_work_sysctls,
945 #ifdef CONFIG_PERF_COUNTERS
947 .ctl_name = CTL_UNNUMBERED,
948 .procname = "perf_counter_paranoid",
949 .data = &sysctl_perf_counter_paranoid,
950 .maxlen = sizeof(sysctl_perf_counter_paranoid),
952 .proc_handler = &proc_dointvec,
955 .ctl_name = CTL_UNNUMBERED,
956 .procname = "perf_counter_mlock_kb",
957 .data = &sysctl_perf_counter_mlock,
958 .maxlen = sizeof(sysctl_perf_counter_mlock),
960 .proc_handler = &proc_dointvec,
963 .ctl_name = CTL_UNNUMBERED,
964 .procname = "perf_counter_max_sample_rate",
965 .data = &sysctl_perf_counter_sample_rate,
966 .maxlen = sizeof(sysctl_perf_counter_sample_rate),
968 .proc_handler = &proc_dointvec,
971 #ifdef CONFIG_KMEMCHECK
973 .ctl_name = CTL_UNNUMBERED,
974 .procname = "kmemcheck",
975 .data = &kmemcheck_enabled,
976 .maxlen = sizeof(int),
978 .proc_handler = &proc_dointvec,
983 * NOTE: do not add new entries to this table unless you have read
984 * Documentation/sysctl/ctl_unnumbered.txt
989 static struct ctl_table vm_table[] = {
991 .ctl_name = VM_OVERCOMMIT_MEMORY,
992 .procname = "overcommit_memory",
993 .data = &sysctl_overcommit_memory,
994 .maxlen = sizeof(sysctl_overcommit_memory),
996 .proc_handler = &proc_dointvec,
999 .ctl_name = VM_PANIC_ON_OOM,
1000 .procname = "panic_on_oom",
1001 .data = &sysctl_panic_on_oom,
1002 .maxlen = sizeof(sysctl_panic_on_oom),
1004 .proc_handler = &proc_dointvec,
1007 .ctl_name = CTL_UNNUMBERED,
1008 .procname = "oom_kill_allocating_task",
1009 .data = &sysctl_oom_kill_allocating_task,
1010 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1012 .proc_handler = &proc_dointvec,
1015 .ctl_name = CTL_UNNUMBERED,
1016 .procname = "oom_dump_tasks",
1017 .data = &sysctl_oom_dump_tasks,
1018 .maxlen = sizeof(sysctl_oom_dump_tasks),
1020 .proc_handler = &proc_dointvec,
1023 .ctl_name = VM_OVERCOMMIT_RATIO,
1024 .procname = "overcommit_ratio",
1025 .data = &sysctl_overcommit_ratio,
1026 .maxlen = sizeof(sysctl_overcommit_ratio),
1028 .proc_handler = &proc_dointvec,
1031 .ctl_name = VM_PAGE_CLUSTER,
1032 .procname = "page-cluster",
1033 .data = &page_cluster,
1034 .maxlen = sizeof(int),
1036 .proc_handler = &proc_dointvec,
1039 .ctl_name = VM_DIRTY_BACKGROUND,
1040 .procname = "dirty_background_ratio",
1041 .data = &dirty_background_ratio,
1042 .maxlen = sizeof(dirty_background_ratio),
1044 .proc_handler = &dirty_background_ratio_handler,
1045 .strategy = &sysctl_intvec,
1047 .extra2 = &one_hundred,
1050 .ctl_name = CTL_UNNUMBERED,
1051 .procname = "dirty_background_bytes",
1052 .data = &dirty_background_bytes,
1053 .maxlen = sizeof(dirty_background_bytes),
1055 .proc_handler = &dirty_background_bytes_handler,
1056 .strategy = &sysctl_intvec,
1060 .ctl_name = VM_DIRTY_RATIO,
1061 .procname = "dirty_ratio",
1062 .data = &vm_dirty_ratio,
1063 .maxlen = sizeof(vm_dirty_ratio),
1065 .proc_handler = &dirty_ratio_handler,
1066 .strategy = &sysctl_intvec,
1068 .extra2 = &one_hundred,
1071 .ctl_name = CTL_UNNUMBERED,
1072 .procname = "dirty_bytes",
1073 .data = &vm_dirty_bytes,
1074 .maxlen = sizeof(vm_dirty_bytes),
1076 .proc_handler = &dirty_bytes_handler,
1077 .strategy = &sysctl_intvec,
1078 .extra1 = &dirty_bytes_min,
1081 .procname = "dirty_writeback_centisecs",
1082 .data = &dirty_writeback_interval,
1083 .maxlen = sizeof(dirty_writeback_interval),
1085 .proc_handler = &dirty_writeback_centisecs_handler,
1088 .procname = "dirty_expire_centisecs",
1089 .data = &dirty_expire_interval,
1090 .maxlen = sizeof(dirty_expire_interval),
1092 .proc_handler = &proc_dointvec,
1095 .ctl_name = VM_NR_PDFLUSH_THREADS,
1096 .procname = "nr_pdflush_threads",
1097 .data = &nr_pdflush_threads,
1098 .maxlen = sizeof nr_pdflush_threads,
1099 .mode = 0444 /* read-only*/,
1100 .proc_handler = &proc_dointvec,
1103 .ctl_name = VM_SWAPPINESS,
1104 .procname = "swappiness",
1105 .data = &vm_swappiness,
1106 .maxlen = sizeof(vm_swappiness),
1108 .proc_handler = &proc_dointvec_minmax,
1109 .strategy = &sysctl_intvec,
1111 .extra2 = &one_hundred,
1113 #ifdef CONFIG_HUGETLB_PAGE
1115 .procname = "nr_hugepages",
1117 .maxlen = sizeof(unsigned long),
1119 .proc_handler = &hugetlb_sysctl_handler,
1120 .extra1 = (void *)&hugetlb_zero,
1121 .extra2 = (void *)&hugetlb_infinity,
1124 .ctl_name = VM_HUGETLB_GROUP,
1125 .procname = "hugetlb_shm_group",
1126 .data = &sysctl_hugetlb_shm_group,
1127 .maxlen = sizeof(gid_t),
1129 .proc_handler = &proc_dointvec,
1132 .ctl_name = CTL_UNNUMBERED,
1133 .procname = "hugepages_treat_as_movable",
1134 .data = &hugepages_treat_as_movable,
1135 .maxlen = sizeof(int),
1137 .proc_handler = &hugetlb_treat_movable_handler,
1140 .ctl_name = CTL_UNNUMBERED,
1141 .procname = "nr_overcommit_hugepages",
1143 .maxlen = sizeof(unsigned long),
1145 .proc_handler = &hugetlb_overcommit_handler,
1146 .extra1 = (void *)&hugetlb_zero,
1147 .extra2 = (void *)&hugetlb_infinity,
1151 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
1152 .procname = "lowmem_reserve_ratio",
1153 .data = &sysctl_lowmem_reserve_ratio,
1154 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1156 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
1157 .strategy = &sysctl_intvec,
1160 .ctl_name = VM_DROP_PAGECACHE,
1161 .procname = "drop_caches",
1162 .data = &sysctl_drop_caches,
1163 .maxlen = sizeof(int),
1165 .proc_handler = drop_caches_sysctl_handler,
1166 .strategy = &sysctl_intvec,
1169 .ctl_name = VM_MIN_FREE_KBYTES,
1170 .procname = "min_free_kbytes",
1171 .data = &min_free_kbytes,
1172 .maxlen = sizeof(min_free_kbytes),
1174 .proc_handler = &min_free_kbytes_sysctl_handler,
1175 .strategy = &sysctl_intvec,
1179 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
1180 .procname = "percpu_pagelist_fraction",
1181 .data = &percpu_pagelist_fraction,
1182 .maxlen = sizeof(percpu_pagelist_fraction),
1184 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
1185 .strategy = &sysctl_intvec,
1186 .extra1 = &min_percpu_pagelist_fract,
1190 .ctl_name = VM_MAX_MAP_COUNT,
1191 .procname = "max_map_count",
1192 .data = &sysctl_max_map_count,
1193 .maxlen = sizeof(sysctl_max_map_count),
1195 .proc_handler = &proc_dointvec
1199 .ctl_name = CTL_UNNUMBERED,
1200 .procname = "nr_trim_pages",
1201 .data = &sysctl_nr_trim_pages,
1202 .maxlen = sizeof(sysctl_nr_trim_pages),
1204 .proc_handler = &proc_dointvec_minmax,
1205 .strategy = &sysctl_intvec,
1210 .ctl_name = VM_LAPTOP_MODE,
1211 .procname = "laptop_mode",
1212 .data = &laptop_mode,
1213 .maxlen = sizeof(laptop_mode),
1215 .proc_handler = &proc_dointvec_jiffies,
1216 .strategy = &sysctl_jiffies,
1219 .ctl_name = VM_BLOCK_DUMP,
1220 .procname = "block_dump",
1221 .data = &block_dump,
1222 .maxlen = sizeof(block_dump),
1224 .proc_handler = &proc_dointvec,
1225 .strategy = &sysctl_intvec,
1229 .ctl_name = VM_VFS_CACHE_PRESSURE,
1230 .procname = "vfs_cache_pressure",
1231 .data = &sysctl_vfs_cache_pressure,
1232 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1234 .proc_handler = &proc_dointvec,
1235 .strategy = &sysctl_intvec,
1238 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1240 .ctl_name = VM_LEGACY_VA_LAYOUT,
1241 .procname = "legacy_va_layout",
1242 .data = &sysctl_legacy_va_layout,
1243 .maxlen = sizeof(sysctl_legacy_va_layout),
1245 .proc_handler = &proc_dointvec,
1246 .strategy = &sysctl_intvec,
1252 .ctl_name = VM_ZONE_RECLAIM_MODE,
1253 .procname = "zone_reclaim_mode",
1254 .data = &zone_reclaim_mode,
1255 .maxlen = sizeof(zone_reclaim_mode),
1257 .proc_handler = &proc_dointvec,
1258 .strategy = &sysctl_intvec,
1262 .ctl_name = VM_MIN_UNMAPPED,
1263 .procname = "min_unmapped_ratio",
1264 .data = &sysctl_min_unmapped_ratio,
1265 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1267 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1268 .strategy = &sysctl_intvec,
1270 .extra2 = &one_hundred,
1273 .ctl_name = VM_MIN_SLAB,
1274 .procname = "min_slab_ratio",
1275 .data = &sysctl_min_slab_ratio,
1276 .maxlen = sizeof(sysctl_min_slab_ratio),
1278 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1279 .strategy = &sysctl_intvec,
1281 .extra2 = &one_hundred,
1286 .ctl_name = CTL_UNNUMBERED,
1287 .procname = "stat_interval",
1288 .data = &sysctl_stat_interval,
1289 .maxlen = sizeof(sysctl_stat_interval),
1291 .proc_handler = &proc_dointvec_jiffies,
1292 .strategy = &sysctl_jiffies,
1296 .ctl_name = CTL_UNNUMBERED,
1297 .procname = "mmap_min_addr",
1298 .data = &mmap_min_addr,
1299 .maxlen = sizeof(unsigned long),
1301 .proc_handler = &proc_doulongvec_minmax,
1305 .ctl_name = CTL_UNNUMBERED,
1306 .procname = "numa_zonelist_order",
1307 .data = &numa_zonelist_order,
1308 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1310 .proc_handler = &numa_zonelist_order_handler,
1311 .strategy = &sysctl_string,
1314 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1315 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1317 .ctl_name = VM_VDSO_ENABLED,
1318 .procname = "vdso_enabled",
1319 .data = &vdso_enabled,
1320 .maxlen = sizeof(vdso_enabled),
1322 .proc_handler = &proc_dointvec,
1323 .strategy = &sysctl_intvec,
1327 #ifdef CONFIG_HIGHMEM
1329 .ctl_name = CTL_UNNUMBERED,
1330 .procname = "highmem_is_dirtyable",
1331 .data = &vm_highmem_is_dirtyable,
1332 .maxlen = sizeof(vm_highmem_is_dirtyable),
1334 .proc_handler = &proc_dointvec_minmax,
1335 .strategy = &sysctl_intvec,
1340 #ifdef CONFIG_UNEVICTABLE_LRU
1342 .ctl_name = CTL_UNNUMBERED,
1343 .procname = "scan_unevictable_pages",
1344 .data = &scan_unevictable_pages,
1345 .maxlen = sizeof(scan_unevictable_pages),
1347 .proc_handler = &scan_unevictable_handler,
1351 * NOTE: do not add new entries to this table unless you have read
1352 * Documentation/sysctl/ctl_unnumbered.txt
1357 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1358 static struct ctl_table binfmt_misc_table[] = {
1363 static struct ctl_table fs_table[] = {
1365 .ctl_name = FS_NRINODE,
1366 .procname = "inode-nr",
1367 .data = &inodes_stat,
1368 .maxlen = 2*sizeof(int),
1370 .proc_handler = &proc_dointvec,
1373 .ctl_name = FS_STATINODE,
1374 .procname = "inode-state",
1375 .data = &inodes_stat,
1376 .maxlen = 7*sizeof(int),
1378 .proc_handler = &proc_dointvec,
1381 .procname = "file-nr",
1382 .data = &files_stat,
1383 .maxlen = 3*sizeof(int),
1385 .proc_handler = &proc_nr_files,
1388 .ctl_name = FS_MAXFILE,
1389 .procname = "file-max",
1390 .data = &files_stat.max_files,
1391 .maxlen = sizeof(int),
1393 .proc_handler = &proc_dointvec,
1396 .ctl_name = CTL_UNNUMBERED,
1397 .procname = "nr_open",
1398 .data = &sysctl_nr_open,
1399 .maxlen = sizeof(int),
1401 .proc_handler = &proc_dointvec_minmax,
1402 .extra1 = &sysctl_nr_open_min,
1403 .extra2 = &sysctl_nr_open_max,
1406 .ctl_name = FS_DENTRY,
1407 .procname = "dentry-state",
1408 .data = &dentry_stat,
1409 .maxlen = 6*sizeof(int),
1411 .proc_handler = &proc_dointvec,
1414 .ctl_name = FS_OVERFLOWUID,
1415 .procname = "overflowuid",
1416 .data = &fs_overflowuid,
1417 .maxlen = sizeof(int),
1419 .proc_handler = &proc_dointvec_minmax,
1420 .strategy = &sysctl_intvec,
1421 .extra1 = &minolduid,
1422 .extra2 = &maxolduid,
1425 .ctl_name = FS_OVERFLOWGID,
1426 .procname = "overflowgid",
1427 .data = &fs_overflowgid,
1428 .maxlen = sizeof(int),
1430 .proc_handler = &proc_dointvec_minmax,
1431 .strategy = &sysctl_intvec,
1432 .extra1 = &minolduid,
1433 .extra2 = &maxolduid,
1435 #ifdef CONFIG_FILE_LOCKING
1437 .ctl_name = FS_LEASES,
1438 .procname = "leases-enable",
1439 .data = &leases_enable,
1440 .maxlen = sizeof(int),
1442 .proc_handler = &proc_dointvec,
1445 #ifdef CONFIG_DNOTIFY
1447 .ctl_name = FS_DIR_NOTIFY,
1448 .procname = "dir-notify-enable",
1449 .data = &dir_notify_enable,
1450 .maxlen = sizeof(int),
1452 .proc_handler = &proc_dointvec,
1456 #ifdef CONFIG_FILE_LOCKING
1458 .ctl_name = FS_LEASE_TIME,
1459 .procname = "lease-break-time",
1460 .data = &lease_break_time,
1461 .maxlen = sizeof(int),
1463 .proc_handler = &proc_dointvec,
1468 .procname = "aio-nr",
1470 .maxlen = sizeof(aio_nr),
1472 .proc_handler = &proc_doulongvec_minmax,
1475 .procname = "aio-max-nr",
1476 .data = &aio_max_nr,
1477 .maxlen = sizeof(aio_max_nr),
1479 .proc_handler = &proc_doulongvec_minmax,
1481 #endif /* CONFIG_AIO */
1482 #ifdef CONFIG_INOTIFY_USER
1484 .ctl_name = FS_INOTIFY,
1485 .procname = "inotify",
1487 .child = inotify_table,
1492 .procname = "epoll",
1494 .child = epoll_table,
1499 .ctl_name = KERN_SETUID_DUMPABLE,
1500 .procname = "suid_dumpable",
1501 .data = &suid_dumpable,
1502 .maxlen = sizeof(int),
1504 .proc_handler = &proc_dointvec_minmax,
1505 .strategy = &sysctl_intvec,
1509 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1511 .ctl_name = CTL_UNNUMBERED,
1512 .procname = "binfmt_misc",
1514 .child = binfmt_misc_table,
1518 * NOTE: do not add new entries to this table unless you have read
1519 * Documentation/sysctl/ctl_unnumbered.txt
1524 static struct ctl_table debug_table[] = {
1525 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1527 .ctl_name = CTL_UNNUMBERED,
1528 .procname = "exception-trace",
1529 .data = &show_unhandled_signals,
1530 .maxlen = sizeof(int),
1532 .proc_handler = proc_dointvec
1538 static struct ctl_table dev_table[] = {
1542 static DEFINE_SPINLOCK(sysctl_lock);
1544 /* called under sysctl_lock */
1545 static int use_table(struct ctl_table_header *p)
1547 if (unlikely(p->unregistering))
1553 /* called under sysctl_lock */
1554 static void unuse_table(struct ctl_table_header *p)
1557 if (unlikely(p->unregistering))
1558 complete(p->unregistering);
1561 /* called under sysctl_lock, will reacquire if has to wait */
1562 static void start_unregistering(struct ctl_table_header *p)
1565 * if p->used is 0, nobody will ever touch that entry again;
1566 * we'll eliminate all paths to it before dropping sysctl_lock
1568 if (unlikely(p->used)) {
1569 struct completion wait;
1570 init_completion(&wait);
1571 p->unregistering = &wait;
1572 spin_unlock(&sysctl_lock);
1573 wait_for_completion(&wait);
1574 spin_lock(&sysctl_lock);
1576 /* anything non-NULL; we'll never dereference it */
1577 p->unregistering = ERR_PTR(-EINVAL);
1580 * do not remove from the list until nobody holds it; walking the
1581 * list in do_sysctl() relies on that.
1583 list_del_init(&p->ctl_entry);
1586 void sysctl_head_get(struct ctl_table_header *head)
1588 spin_lock(&sysctl_lock);
1590 spin_unlock(&sysctl_lock);
1593 void sysctl_head_put(struct ctl_table_header *head)
1595 spin_lock(&sysctl_lock);
1598 spin_unlock(&sysctl_lock);
1601 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1605 spin_lock(&sysctl_lock);
1606 if (!use_table(head))
1607 head = ERR_PTR(-ENOENT);
1608 spin_unlock(&sysctl_lock);
1612 void sysctl_head_finish(struct ctl_table_header *head)
1616 spin_lock(&sysctl_lock);
1618 spin_unlock(&sysctl_lock);
1621 static struct ctl_table_set *
1622 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1624 struct ctl_table_set *set = &root->default_set;
1626 set = root->lookup(root, namespaces);
1630 static struct list_head *
1631 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1633 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1637 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1638 struct ctl_table_header *prev)
1640 struct ctl_table_root *root;
1641 struct list_head *header_list;
1642 struct ctl_table_header *head;
1643 struct list_head *tmp;
1645 spin_lock(&sysctl_lock);
1648 tmp = &prev->ctl_entry;
1652 tmp = &root_table_header.ctl_entry;
1654 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1656 if (!use_table(head))
1658 spin_unlock(&sysctl_lock);
1663 header_list = lookup_header_list(root, namespaces);
1664 if (tmp != header_list)
1668 root = list_entry(root->root_list.next,
1669 struct ctl_table_root, root_list);
1670 if (root == &sysctl_table_root)
1672 header_list = lookup_header_list(root, namespaces);
1673 } while (list_empty(header_list));
1674 tmp = header_list->next;
1677 spin_unlock(&sysctl_lock);
1681 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1683 return __sysctl_head_next(current->nsproxy, prev);
1686 void register_sysctl_root(struct ctl_table_root *root)
1688 spin_lock(&sysctl_lock);
1689 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1690 spin_unlock(&sysctl_lock);
1693 #ifdef CONFIG_SYSCTL_SYSCALL
1694 /* Perform the actual read/write of a sysctl table entry. */
1695 static int do_sysctl_strategy(struct ctl_table_root *root,
1696 struct ctl_table *table,
1697 void __user *oldval, size_t __user *oldlenp,
1698 void __user *newval, size_t newlen)
1706 if (sysctl_perm(root, table, op))
1709 if (table->strategy) {
1710 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1717 /* If there is no strategy routine, or if the strategy returns
1718 * zero, proceed with automatic r/w */
1719 if (table->data && table->maxlen) {
1720 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1727 static int parse_table(int __user *name, int nlen,
1728 void __user *oldval, size_t __user *oldlenp,
1729 void __user *newval, size_t newlen,
1730 struct ctl_table_root *root,
1731 struct ctl_table *table)
1737 if (get_user(n, name))
1739 for ( ; table->ctl_name || table->procname; table++) {
1740 if (!table->ctl_name)
1742 if (n == table->ctl_name) {
1745 if (sysctl_perm(root, table, MAY_EXEC))
1749 table = table->child;
1752 error = do_sysctl_strategy(root, table,
1761 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1762 void __user *newval, size_t newlen)
1764 struct ctl_table_header *head;
1765 int error = -ENOTDIR;
1767 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1771 if (!oldlenp || get_user(old_len, oldlenp))
1775 for (head = sysctl_head_next(NULL); head;
1776 head = sysctl_head_next(head)) {
1777 error = parse_table(name, nlen, oldval, oldlenp,
1779 head->root, head->ctl_table);
1780 if (error != -ENOTDIR) {
1781 sysctl_head_finish(head);
1788 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1790 struct __sysctl_args tmp;
1793 if (copy_from_user(&tmp, args, sizeof(tmp)))
1796 error = deprecated_sysctl_warning(&tmp);
1801 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1802 tmp.newval, tmp.newlen);
1807 #endif /* CONFIG_SYSCTL_SYSCALL */
1810 * sysctl_perm does NOT grant the superuser all rights automatically, because
1811 * some sysctl variables are readonly even to root.
1814 static int test_perm(int mode, int op)
1816 if (!current_euid())
1818 else if (in_egroup_p(0))
1820 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1825 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1830 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1834 if (root->permissions)
1835 mode = root->permissions(root, current->nsproxy, table);
1839 return test_perm(mode, op);
1842 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1844 for (; table->ctl_name || table->procname; table++) {
1845 table->parent = parent;
1847 sysctl_set_parent(table, table->child);
1851 static __init int sysctl_init(void)
1853 sysctl_set_parent(NULL, root_table);
1854 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1857 err = sysctl_check_table(current->nsproxy, root_table);
1863 core_initcall(sysctl_init);
1865 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1866 struct ctl_table *table)
1868 struct ctl_table *p;
1869 const char *s = branch->procname;
1871 /* branch should have named subdirectory as its first element */
1872 if (!s || !branch->child)
1875 /* ... and nothing else */
1876 if (branch[1].procname || branch[1].ctl_name)
1879 /* table should contain subdirectory with the same name */
1880 for (p = table; p->procname || p->ctl_name; p++) {
1883 if (p->procname && strcmp(p->procname, s) == 0)
1889 /* see if attaching q to p would be an improvement */
1890 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1892 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1893 struct ctl_table *next;
1895 int not_in_parent = !p->attached_by;
1897 while ((next = is_branch_in(by, to)) != NULL) {
1898 if (by == q->attached_by)
1900 if (to == p->attached_by)
1906 if (is_better && not_in_parent) {
1907 q->attached_by = by;
1908 q->attached_to = to;
1914 * __register_sysctl_paths - register a sysctl hierarchy
1915 * @root: List of sysctl headers to register on
1916 * @namespaces: Data to compute which lists of sysctl entries are visible
1917 * @path: The path to the directory the sysctl table is in.
1918 * @table: the top-level table structure
1920 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1921 * array. A completely 0 filled entry terminates the table.
1923 * The members of the &struct ctl_table structure are used as follows:
1925 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1926 * must be unique within that level of sysctl
1928 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1929 * enter a sysctl file
1931 * data - a pointer to data for use by proc_handler
1933 * maxlen - the maximum size in bytes of the data
1935 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1937 * child - a pointer to the child sysctl table if this entry is a directory, or
1940 * proc_handler - the text handler routine (described below)
1942 * strategy - the strategy routine (described below)
1944 * de - for internal use by the sysctl routines
1946 * extra1, extra2 - extra pointers usable by the proc handler routines
1948 * Leaf nodes in the sysctl tree will be represented by a single file
1949 * under /proc; non-leaf nodes will be represented by directories.
1951 * sysctl(2) can automatically manage read and write requests through
1952 * the sysctl table. The data and maxlen fields of the ctl_table
1953 * struct enable minimal validation of the values being written to be
1954 * performed, and the mode field allows minimal authentication.
1956 * More sophisticated management can be enabled by the provision of a
1957 * strategy routine with the table entry. This will be called before
1958 * any automatic read or write of the data is performed.
1960 * The strategy routine may return
1962 * < 0 - Error occurred (error is passed to user process)
1964 * 0 - OK - proceed with automatic read or write.
1966 * > 0 - OK - read or write has been done by the strategy routine, so
1967 * return immediately.
1969 * There must be a proc_handler routine for any terminal nodes
1970 * mirrored under /proc/sys (non-terminals are handled by a built-in
1971 * directory handler). Several default handlers are available to
1972 * cover common cases -
1974 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1975 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1976 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1978 * It is the handler's job to read the input buffer from user memory
1979 * and process it. The handler should return 0 on success.
1981 * This routine returns %NULL on a failure to register, and a pointer
1982 * to the table header on success.
1984 struct ctl_table_header *__register_sysctl_paths(
1985 struct ctl_table_root *root,
1986 struct nsproxy *namespaces,
1987 const struct ctl_path *path, struct ctl_table *table)
1989 struct ctl_table_header *header;
1990 struct ctl_table *new, **prevp;
1991 unsigned int n, npath;
1992 struct ctl_table_set *set;
1994 /* Count the path components */
1995 for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
1999 * For each path component, allocate a 2-element ctl_table array.
2000 * The first array element will be filled with the sysctl entry
2001 * for this, the second will be the sentinel (ctl_name == 0).
2003 * We allocate everything in one go so that we don't have to
2004 * worry about freeing additional memory in unregister_sysctl_table.
2006 header = kzalloc(sizeof(struct ctl_table_header) +
2007 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
2011 new = (struct ctl_table *) (header + 1);
2013 /* Now connect the dots */
2014 prevp = &header->ctl_table;
2015 for (n = 0; n < npath; ++n, ++path) {
2016 /* Copy the procname */
2017 new->procname = path->procname;
2018 new->ctl_name = path->ctl_name;
2022 prevp = &new->child;
2027 header->ctl_table_arg = table;
2029 INIT_LIST_HEAD(&header->ctl_entry);
2031 header->unregistering = NULL;
2032 header->root = root;
2033 sysctl_set_parent(NULL, header->ctl_table);
2035 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2036 if (sysctl_check_table(namespaces, header->ctl_table)) {
2041 spin_lock(&sysctl_lock);
2042 header->set = lookup_header_set(root, namespaces);
2043 header->attached_by = header->ctl_table;
2044 header->attached_to = root_table;
2045 header->parent = &root_table_header;
2046 for (set = header->set; set; set = set->parent) {
2047 struct ctl_table_header *p;
2048 list_for_each_entry(p, &set->list, ctl_entry) {
2049 if (p->unregistering)
2051 try_attach(p, header);
2054 header->parent->count++;
2055 list_add_tail(&header->ctl_entry, &header->set->list);
2056 spin_unlock(&sysctl_lock);
2062 * register_sysctl_table_path - register a sysctl table hierarchy
2063 * @path: The path to the directory the sysctl table is in.
2064 * @table: the top-level table structure
2066 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2067 * array. A completely 0 filled entry terminates the table.
2069 * See __register_sysctl_paths for more details.
2071 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2072 struct ctl_table *table)
2074 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2079 * register_sysctl_table - register a sysctl table hierarchy
2080 * @table: the top-level table structure
2082 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2083 * array. A completely 0 filled entry terminates the table.
2085 * See register_sysctl_paths for more details.
2087 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2089 static const struct ctl_path null_path[] = { {} };
2091 return register_sysctl_paths(null_path, table);
2095 * unregister_sysctl_table - unregister a sysctl table hierarchy
2096 * @header: the header returned from register_sysctl_table
2098 * Unregisters the sysctl table and all children. proc entries may not
2099 * actually be removed until they are no longer used by anyone.
2101 void unregister_sysctl_table(struct ctl_table_header * header)
2108 spin_lock(&sysctl_lock);
2109 start_unregistering(header);
2110 if (!--header->parent->count) {
2112 kfree(header->parent);
2114 if (!--header->count)
2116 spin_unlock(&sysctl_lock);
2119 int sysctl_is_seen(struct ctl_table_header *p)
2121 struct ctl_table_set *set = p->set;
2123 spin_lock(&sysctl_lock);
2124 if (p->unregistering)
2126 else if (!set->is_seen)
2129 res = set->is_seen(set);
2130 spin_unlock(&sysctl_lock);
2134 void setup_sysctl_set(struct ctl_table_set *p,
2135 struct ctl_table_set *parent,
2136 int (*is_seen)(struct ctl_table_set *))
2138 INIT_LIST_HEAD(&p->list);
2139 p->parent = parent ? parent : &sysctl_table_root.default_set;
2140 p->is_seen = is_seen;
2143 #else /* !CONFIG_SYSCTL */
2144 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2149 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2150 struct ctl_table *table)
2155 void unregister_sysctl_table(struct ctl_table_header * table)
2159 void setup_sysctl_set(struct ctl_table_set *p,
2160 struct ctl_table_set *parent,
2161 int (*is_seen)(struct ctl_table_set *))
2165 void sysctl_head_put(struct ctl_table_header *head)
2169 #endif /* CONFIG_SYSCTL */
2175 #ifdef CONFIG_PROC_SYSCTL
2177 static int _proc_do_string(void* data, int maxlen, int write,
2178 struct file *filp, void __user *buffer,
2179 size_t *lenp, loff_t *ppos)
2185 if (!data || !maxlen || !*lenp) {
2193 while (len < *lenp) {
2194 if (get_user(c, p++))
2196 if (c == 0 || c == '\n')
2202 if(copy_from_user(data, buffer, len))
2204 ((char *) data)[len] = 0;
2222 if(copy_to_user(buffer, data, len))
2225 if(put_user('\n', ((char __user *) buffer) + len))
2236 * proc_dostring - read a string sysctl
2237 * @table: the sysctl table
2238 * @write: %TRUE if this is a write to the sysctl file
2239 * @filp: the file structure
2240 * @buffer: the user buffer
2241 * @lenp: the size of the user buffer
2242 * @ppos: file position
2244 * Reads/writes a string from/to the user buffer. If the kernel
2245 * buffer provided is not large enough to hold the string, the
2246 * string is truncated. The copied string is %NULL-terminated.
2247 * If the string is being read by the user process, it is copied
2248 * and a newline '\n' is added. It is truncated if the buffer is
2251 * Returns 0 on success.
2253 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2254 void __user *buffer, size_t *lenp, loff_t *ppos)
2256 return _proc_do_string(table->data, table->maxlen, write, filp,
2257 buffer, lenp, ppos);
2261 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2263 int write, void *data)
2266 *valp = *negp ? -*lvalp : *lvalp;
2271 *lvalp = (unsigned long)-val;
2274 *lvalp = (unsigned long)val;
2280 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2281 int write, struct file *filp, void __user *buffer,
2282 size_t *lenp, loff_t *ppos,
2283 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2284 int write, void *data),
2287 #define TMPBUFLEN 21
2288 int *i, vleft, first=1, neg, val;
2292 char buf[TMPBUFLEN], *p;
2293 char __user *s = buffer;
2295 if (!tbl_data || !table->maxlen || !*lenp ||
2296 (*ppos && !write)) {
2301 i = (int *) tbl_data;
2302 vleft = table->maxlen / sizeof(*i);
2306 conv = do_proc_dointvec_conv;
2308 for (; left && vleft--; i++, first=0) {
2323 if (len > sizeof(buf) - 1)
2324 len = sizeof(buf) - 1;
2325 if (copy_from_user(buf, s, len))
2329 if (*p == '-' && left > 1) {
2333 if (*p < '0' || *p > '9')
2336 lval = simple_strtoul(p, &p, 0);
2339 if ((len < left) && *p && !isspace(*p))
2346 if (conv(&neg, &lval, i, 1, data))
2353 if (conv(&neg, &lval, i, 0, data))
2356 sprintf(p, "%s%lu", neg ? "-" : "", lval);
2360 if(copy_to_user(s, buf, len))
2367 if (!write && !first && left) {
2368 if(put_user('\n', s))
2375 if (get_user(c, s++))
2390 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2391 void __user *buffer, size_t *lenp, loff_t *ppos,
2392 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2393 int write, void *data),
2396 return __do_proc_dointvec(table->data, table, write, filp,
2397 buffer, lenp, ppos, conv, data);
2401 * proc_dointvec - read a vector of integers
2402 * @table: the sysctl table
2403 * @write: %TRUE if this is a write to the sysctl file
2404 * @filp: the file structure
2405 * @buffer: the user buffer
2406 * @lenp: the size of the user buffer
2407 * @ppos: file position
2409 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2410 * values from/to the user buffer, treated as an ASCII string.
2412 * Returns 0 on success.
2414 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2415 void __user *buffer, size_t *lenp, loff_t *ppos)
2417 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2422 * Taint values can only be increased
2423 * This means we can safely use a temporary.
2425 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2426 void __user *buffer, size_t *lenp, loff_t *ppos)
2429 unsigned long tmptaint = get_taint();
2432 if (write && !capable(CAP_SYS_ADMIN))
2437 err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2443 * Poor man's atomic or. Not worth adding a primitive
2444 * to everyone's atomic.h for this
2447 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2448 if ((tmptaint >> i) & 1)
2456 struct do_proc_dointvec_minmax_conv_param {
2461 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2463 int write, void *data)
2465 struct do_proc_dointvec_minmax_conv_param *param = data;
2467 int val = *negp ? -*lvalp : *lvalp;
2468 if ((param->min && *param->min > val) ||
2469 (param->max && *param->max < val))
2476 *lvalp = (unsigned long)-val;
2479 *lvalp = (unsigned long)val;
2486 * proc_dointvec_minmax - read a vector of integers with min/max values
2487 * @table: the sysctl table
2488 * @write: %TRUE if this is a write to the sysctl file
2489 * @filp: the file structure
2490 * @buffer: the user buffer
2491 * @lenp: the size of the user buffer
2492 * @ppos: file position
2494 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2495 * values from/to the user buffer, treated as an ASCII string.
2497 * This routine will ensure the values are within the range specified by
2498 * table->extra1 (min) and table->extra2 (max).
2500 * Returns 0 on success.
2502 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2503 void __user *buffer, size_t *lenp, loff_t *ppos)
2505 struct do_proc_dointvec_minmax_conv_param param = {
2506 .min = (int *) table->extra1,
2507 .max = (int *) table->extra2,
2509 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2510 do_proc_dointvec_minmax_conv, ¶m);
2513 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2515 void __user *buffer,
2516 size_t *lenp, loff_t *ppos,
2517 unsigned long convmul,
2518 unsigned long convdiv)
2520 #define TMPBUFLEN 21
2521 unsigned long *i, *min, *max, val;
2522 int vleft, first=1, neg;
2524 char buf[TMPBUFLEN], *p;
2525 char __user *s = buffer;
2527 if (!data || !table->maxlen || !*lenp ||
2528 (*ppos && !write)) {
2533 i = (unsigned long *) data;
2534 min = (unsigned long *) table->extra1;
2535 max = (unsigned long *) table->extra2;
2536 vleft = table->maxlen / sizeof(unsigned long);
2539 for (; left && vleft--; i++, min++, max++, first=0) {
2554 if (len > TMPBUFLEN-1)
2556 if (copy_from_user(buf, s, len))
2560 if (*p == '-' && left > 1) {
2564 if (*p < '0' || *p > '9')
2566 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2568 if ((len < left) && *p && !isspace(*p))
2577 if ((min && val < *min) || (max && val > *max))
2584 sprintf(p, "%lu", convdiv * (*i) / convmul);
2588 if(copy_to_user(s, buf, len))
2595 if (!write && !first && left) {
2596 if(put_user('\n', s))
2603 if (get_user(c, s++))
2618 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2620 void __user *buffer,
2621 size_t *lenp, loff_t *ppos,
2622 unsigned long convmul,
2623 unsigned long convdiv)
2625 return __do_proc_doulongvec_minmax(table->data, table, write,
2626 filp, buffer, lenp, ppos, convmul, convdiv);
2630 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2631 * @table: the sysctl table
2632 * @write: %TRUE if this is a write to the sysctl file
2633 * @filp: the file structure
2634 * @buffer: the user buffer
2635 * @lenp: the size of the user buffer
2636 * @ppos: file position
2638 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2639 * values from/to the user buffer, treated as an ASCII string.
2641 * This routine will ensure the values are within the range specified by
2642 * table->extra1 (min) and table->extra2 (max).
2644 * Returns 0 on success.
2646 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2647 void __user *buffer, size_t *lenp, loff_t *ppos)
2649 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2653 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2654 * @table: the sysctl table
2655 * @write: %TRUE if this is a write to the sysctl file
2656 * @filp: the file structure
2657 * @buffer: the user buffer
2658 * @lenp: the size of the user buffer
2659 * @ppos: file position
2661 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2662 * values from/to the user buffer, treated as an ASCII string. The values
2663 * are treated as milliseconds, and converted to jiffies when they are stored.
2665 * This routine will ensure the values are within the range specified by
2666 * table->extra1 (min) and table->extra2 (max).
2668 * Returns 0 on success.
2670 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2672 void __user *buffer,
2673 size_t *lenp, loff_t *ppos)
2675 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2676 lenp, ppos, HZ, 1000l);
2680 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2682 int write, void *data)
2685 if (*lvalp > LONG_MAX / HZ)
2687 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2693 lval = (unsigned long)-val;
2696 lval = (unsigned long)val;
2703 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2705 int write, void *data)
2708 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2710 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2716 lval = (unsigned long)-val;
2719 lval = (unsigned long)val;
2721 *lvalp = jiffies_to_clock_t(lval);
2726 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2728 int write, void *data)
2731 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2737 lval = (unsigned long)-val;
2740 lval = (unsigned long)val;
2742 *lvalp = jiffies_to_msecs(lval);
2748 * proc_dointvec_jiffies - read a vector of integers as seconds
2749 * @table: the sysctl table
2750 * @write: %TRUE if this is a write to the sysctl file
2751 * @filp: the file structure
2752 * @buffer: the user buffer
2753 * @lenp: the size of the user buffer
2754 * @ppos: file position
2756 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2757 * values from/to the user buffer, treated as an ASCII string.
2758 * The values read are assumed to be in seconds, and are converted into
2761 * Returns 0 on success.
2763 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2764 void __user *buffer, size_t *lenp, loff_t *ppos)
2766 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2767 do_proc_dointvec_jiffies_conv,NULL);
2771 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2772 * @table: the sysctl table
2773 * @write: %TRUE if this is a write to the sysctl file
2774 * @filp: the file structure
2775 * @buffer: the user buffer
2776 * @lenp: the size of the user buffer
2777 * @ppos: pointer to the file position
2779 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2780 * values from/to the user buffer, treated as an ASCII string.
2781 * The values read are assumed to be in 1/USER_HZ seconds, and
2782 * are converted into jiffies.
2784 * Returns 0 on success.
2786 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2787 void __user *buffer, size_t *lenp, loff_t *ppos)
2789 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2790 do_proc_dointvec_userhz_jiffies_conv,NULL);
2794 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2795 * @table: the sysctl table
2796 * @write: %TRUE if this is a write to the sysctl file
2797 * @filp: the file structure
2798 * @buffer: the user buffer
2799 * @lenp: the size of the user buffer
2800 * @ppos: file position
2801 * @ppos: the current position in the file
2803 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2804 * values from/to the user buffer, treated as an ASCII string.
2805 * The values read are assumed to be in 1/1000 seconds, and
2806 * are converted into jiffies.
2808 * Returns 0 on success.
2810 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2811 void __user *buffer, size_t *lenp, loff_t *ppos)
2813 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2814 do_proc_dointvec_ms_jiffies_conv, NULL);
2817 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2818 void __user *buffer, size_t *lenp, loff_t *ppos)
2820 struct pid *new_pid;
2824 tmp = pid_vnr(cad_pid);
2826 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2827 lenp, ppos, NULL, NULL);
2831 new_pid = find_get_pid(tmp);
2835 put_pid(xchg(&cad_pid, new_pid));
2839 #else /* CONFIG_PROC_FS */
2841 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2842 void __user *buffer, size_t *lenp, loff_t *ppos)
2847 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2848 void __user *buffer, size_t *lenp, loff_t *ppos)
2853 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2854 void __user *buffer, size_t *lenp, loff_t *ppos)
2859 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2860 void __user *buffer, size_t *lenp, loff_t *ppos)
2865 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2866 void __user *buffer, size_t *lenp, loff_t *ppos)
2871 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2872 void __user *buffer, size_t *lenp, loff_t *ppos)
2877 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2878 void __user *buffer, size_t *lenp, loff_t *ppos)
2883 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2885 void __user *buffer,
2886 size_t *lenp, loff_t *ppos)
2892 #endif /* CONFIG_PROC_FS */
2895 #ifdef CONFIG_SYSCTL_SYSCALL
2897 * General sysctl support routines
2900 /* The generic sysctl data routine (used if no strategy routine supplied) */
2901 int sysctl_data(struct ctl_table *table,
2902 void __user *oldval, size_t __user *oldlenp,
2903 void __user *newval, size_t newlen)
2907 /* Get out of I don't have a variable */
2908 if (!table->data || !table->maxlen)
2911 if (oldval && oldlenp) {
2912 if (get_user(len, oldlenp))
2915 if (len > table->maxlen)
2916 len = table->maxlen;
2917 if (copy_to_user(oldval, table->data, len))
2919 if (put_user(len, oldlenp))
2924 if (newval && newlen) {
2925 if (newlen > table->maxlen)
2926 newlen = table->maxlen;
2928 if (copy_from_user(table->data, newval, newlen))
2934 /* The generic string strategy routine: */
2935 int sysctl_string(struct ctl_table *table,
2936 void __user *oldval, size_t __user *oldlenp,
2937 void __user *newval, size_t newlen)
2939 if (!table->data || !table->maxlen)
2942 if (oldval && oldlenp) {
2944 if (get_user(bufsize, oldlenp))
2947 size_t len = strlen(table->data), copied;
2949 /* This shouldn't trigger for a well-formed sysctl */
2950 if (len > table->maxlen)
2951 len = table->maxlen;
2953 /* Copy up to a max of bufsize-1 bytes of the string */
2954 copied = (len >= bufsize) ? bufsize - 1 : len;
2956 if (copy_to_user(oldval, table->data, copied) ||
2957 put_user(0, (char __user *)(oldval + copied)))
2959 if (put_user(len, oldlenp))
2963 if (newval && newlen) {
2964 size_t len = newlen;
2965 if (len > table->maxlen)
2966 len = table->maxlen;
2967 if(copy_from_user(table->data, newval, len))
2969 if (len == table->maxlen)
2971 ((char *) table->data)[len] = 0;
2977 * This function makes sure that all of the integers in the vector
2978 * are between the minimum and maximum values given in the arrays
2979 * table->extra1 and table->extra2, respectively.
2981 int sysctl_intvec(struct ctl_table *table,
2982 void __user *oldval, size_t __user *oldlenp,
2983 void __user *newval, size_t newlen)
2986 if (newval && newlen) {
2987 int __user *vec = (int __user *) newval;
2988 int *min = (int *) table->extra1;
2989 int *max = (int *) table->extra2;
2993 if (newlen % sizeof(int) != 0)
2996 if (!table->extra1 && !table->extra2)
2999 if (newlen > table->maxlen)
3000 newlen = table->maxlen;
3001 length = newlen / sizeof(int);
3003 for (i = 0; i < length; i++) {
3005 if (get_user(value, vec + i))
3007 if (min && value < min[i])
3009 if (max && value > max[i])
3016 /* Strategy function to convert jiffies to seconds */
3017 int sysctl_jiffies(struct ctl_table *table,
3018 void __user *oldval, size_t __user *oldlenp,
3019 void __user *newval, size_t newlen)
3021 if (oldval && oldlenp) {
3024 if (get_user(olen, oldlenp))
3029 if (olen < sizeof(int))
3032 val = *(int *)(table->data) / HZ;
3033 if (put_user(val, (int __user *)oldval))
3035 if (put_user(sizeof(int), oldlenp))
3039 if (newval && newlen) {
3041 if (newlen != sizeof(int))
3043 if (get_user(new, (int __user *)newval))
3045 *(int *)(table->data) = new*HZ;
3050 /* Strategy function to convert jiffies to seconds */
3051 int sysctl_ms_jiffies(struct ctl_table *table,
3052 void __user *oldval, size_t __user *oldlenp,
3053 void __user *newval, size_t newlen)
3055 if (oldval && oldlenp) {
3058 if (get_user(olen, oldlenp))
3063 if (olen < sizeof(int))
3066 val = jiffies_to_msecs(*(int *)(table->data));
3067 if (put_user(val, (int __user *)oldval))
3069 if (put_user(sizeof(int), oldlenp))
3073 if (newval && newlen) {
3075 if (newlen != sizeof(int))
3077 if (get_user(new, (int __user *)newval))
3079 *(int *)(table->data) = msecs_to_jiffies(new);
3086 #else /* CONFIG_SYSCTL_SYSCALL */
3089 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3091 struct __sysctl_args tmp;
3094 if (copy_from_user(&tmp, args, sizeof(tmp)))
3097 error = deprecated_sysctl_warning(&tmp);
3099 /* If no error reading the parameters then just -ENOSYS ... */
3106 int sysctl_data(struct ctl_table *table,
3107 void __user *oldval, size_t __user *oldlenp,
3108 void __user *newval, size_t newlen)
3113 int sysctl_string(struct ctl_table *table,
3114 void __user *oldval, size_t __user *oldlenp,
3115 void __user *newval, size_t newlen)
3120 int sysctl_intvec(struct ctl_table *table,
3121 void __user *oldval, size_t __user *oldlenp,
3122 void __user *newval, size_t newlen)
3127 int sysctl_jiffies(struct ctl_table *table,
3128 void __user *oldval, size_t __user *oldlenp,
3129 void __user *newval, size_t newlen)
3134 int sysctl_ms_jiffies(struct ctl_table *table,
3135 void __user *oldval, size_t __user *oldlenp,
3136 void __user *newval, size_t newlen)
3141 #endif /* CONFIG_SYSCTL_SYSCALL */
3143 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3145 static int msg_count;
3146 int name[CTL_MAXNAME];
3149 /* Check args->nlen. */
3150 if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3153 /* Read in the sysctl name for better debug message logging */
3154 for (i = 0; i < args->nlen; i++)
3155 if (get_user(name[i], args->name + i))
3158 /* Ignore accesses to kernel.version */
3159 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3162 if (msg_count < 5) {
3165 "warning: process `%s' used the deprecated sysctl "
3166 "system call with ", current->comm);
3167 for (i = 0; i < args->nlen; i++)
3168 printk("%d.", name[i]);
3175 * No sense putting this after each symbol definition, twice,
3176 * exception granted :-)
3178 EXPORT_SYMBOL(proc_dointvec);
3179 EXPORT_SYMBOL(proc_dointvec_jiffies);
3180 EXPORT_SYMBOL(proc_dointvec_minmax);
3181 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3182 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3183 EXPORT_SYMBOL(proc_dostring);
3184 EXPORT_SYMBOL(proc_doulongvec_minmax);
3185 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3186 EXPORT_SYMBOL(register_sysctl_table);
3187 EXPORT_SYMBOL(register_sysctl_paths);
3188 EXPORT_SYMBOL(sysctl_intvec);
3189 EXPORT_SYMBOL(sysctl_jiffies);
3190 EXPORT_SYMBOL(sysctl_ms_jiffies);
3191 EXPORT_SYMBOL(sysctl_string);
3192 EXPORT_SYMBOL(sysctl_data);
3193 EXPORT_SYMBOL(unregister_sysctl_table);