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/security.h>
53 #include <linux/slow-work.h>
54 #include <linux/perf_counter.h>
56 #include <asm/uaccess.h>
57 #include <asm/processor.h>
61 #include <asm/stacktrace.h>
65 static int deprecated_sysctl_warning(struct __sysctl_args *args);
67 #if defined(CONFIG_SYSCTL)
69 /* External variables not in a header file. */
71 extern int print_fatal_signals;
72 extern int sysctl_overcommit_memory;
73 extern int sysctl_overcommit_ratio;
74 extern int sysctl_panic_on_oom;
75 extern int sysctl_oom_kill_allocating_task;
76 extern int sysctl_oom_dump_tasks;
77 extern int max_threads;
78 extern int core_uses_pid;
79 extern int suid_dumpable;
80 extern char core_pattern[];
82 extern int min_free_kbytes;
83 extern int pid_max_min, pid_max_max;
84 extern int sysctl_drop_caches;
85 extern int percpu_pagelist_fraction;
86 extern int compat_log;
87 extern int latencytop_enabled;
88 extern int sysctl_nr_open_min, sysctl_nr_open_max;
90 extern int sysctl_nr_trim_pages;
92 #ifdef CONFIG_RCU_TORTURE_TEST
93 extern int rcutorture_runnable;
94 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
96 /* Constants used for minimum and maximum */
97 #ifdef CONFIG_DETECT_SOFTLOCKUP
98 static int sixty = 60;
99 static int neg_one = -1;
103 static int __maybe_unused one = 1;
104 static int __maybe_unused two = 2;
105 static unsigned long one_ul = 1;
106 static int one_hundred = 100;
108 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
109 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
111 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
112 static int maxolduid = 65535;
113 static int minolduid;
114 static int min_percpu_pagelist_fract = 8;
116 static int ngroups_max = NGROUPS_MAX;
118 #ifdef CONFIG_MODULES
119 extern char modprobe_path[];
120 extern int modules_disabled;
122 #ifdef CONFIG_CHR_DEV_SG
123 extern int sg_big_buff;
127 #include <asm/system.h>
130 #ifdef CONFIG_SPARC64
131 extern int sysctl_tsb_ratio;
135 extern int pwrsw_enabled;
136 extern int unaligned_enabled;
140 #ifdef CONFIG_MATHEMU
141 extern int sysctl_ieee_emulation_warnings;
143 extern int sysctl_userprocess_debug;
144 extern int spin_retry;
147 #ifdef CONFIG_BSD_PROCESS_ACCT
148 extern int acct_parm[];
152 extern int no_unaligned_warning;
153 extern int unaligned_dump_stack;
156 #ifdef CONFIG_RT_MUTEXES
157 extern int max_lock_depth;
160 #ifdef CONFIG_PROC_SYSCTL
161 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
162 void __user *buffer, size_t *lenp, loff_t *ppos);
163 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
164 void __user *buffer, size_t *lenp, loff_t *ppos);
167 static struct ctl_table root_table[];
168 static struct ctl_table_root sysctl_table_root;
169 static struct ctl_table_header root_table_header = {
171 .ctl_table = root_table,
172 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
173 .root = &sysctl_table_root,
174 .set = &sysctl_table_root.default_set,
176 static struct ctl_table_root sysctl_table_root = {
177 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
178 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
181 static struct ctl_table kern_table[];
182 static struct ctl_table vm_table[];
183 static struct ctl_table fs_table[];
184 static struct ctl_table debug_table[];
185 static struct ctl_table dev_table[];
186 extern struct ctl_table random_table[];
187 #ifdef CONFIG_INOTIFY_USER
188 extern struct ctl_table inotify_table[];
191 extern struct ctl_table epoll_table[];
194 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
195 int sysctl_legacy_va_layout;
198 extern int prove_locking;
199 extern int lock_stat;
201 /* The default sysctl tables: */
203 static struct ctl_table root_table[] = {
205 .ctl_name = CTL_KERN,
206 .procname = "kernel",
223 .ctl_name = CTL_DEBUG,
226 .child = debug_table,
235 * NOTE: do not add new entries to this table unless you have read
236 * Documentation/sysctl/ctl_unnumbered.txt
241 #ifdef CONFIG_SCHED_DEBUG
242 static int min_sched_granularity_ns = 100000; /* 100 usecs */
243 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
244 static int min_wakeup_granularity_ns; /* 0 usecs */
245 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
248 static struct ctl_table kern_table[] = {
250 .ctl_name = CTL_UNNUMBERED,
251 .procname = "sched_child_runs_first",
252 .data = &sysctl_sched_child_runs_first,
253 .maxlen = sizeof(unsigned int),
255 .proc_handler = &proc_dointvec,
257 #ifdef CONFIG_SCHED_DEBUG
259 .ctl_name = CTL_UNNUMBERED,
260 .procname = "sched_min_granularity_ns",
261 .data = &sysctl_sched_min_granularity,
262 .maxlen = sizeof(unsigned int),
264 .proc_handler = &sched_nr_latency_handler,
265 .strategy = &sysctl_intvec,
266 .extra1 = &min_sched_granularity_ns,
267 .extra2 = &max_sched_granularity_ns,
270 .ctl_name = CTL_UNNUMBERED,
271 .procname = "sched_latency_ns",
272 .data = &sysctl_sched_latency,
273 .maxlen = sizeof(unsigned int),
275 .proc_handler = &sched_nr_latency_handler,
276 .strategy = &sysctl_intvec,
277 .extra1 = &min_sched_granularity_ns,
278 .extra2 = &max_sched_granularity_ns,
281 .ctl_name = CTL_UNNUMBERED,
282 .procname = "sched_wakeup_granularity_ns",
283 .data = &sysctl_sched_wakeup_granularity,
284 .maxlen = sizeof(unsigned int),
286 .proc_handler = &proc_dointvec_minmax,
287 .strategy = &sysctl_intvec,
288 .extra1 = &min_wakeup_granularity_ns,
289 .extra2 = &max_wakeup_granularity_ns,
292 .ctl_name = CTL_UNNUMBERED,
293 .procname = "sched_shares_ratelimit",
294 .data = &sysctl_sched_shares_ratelimit,
295 .maxlen = sizeof(unsigned int),
297 .proc_handler = &proc_dointvec,
300 .ctl_name = CTL_UNNUMBERED,
301 .procname = "sched_shares_thresh",
302 .data = &sysctl_sched_shares_thresh,
303 .maxlen = sizeof(unsigned int),
305 .proc_handler = &proc_dointvec_minmax,
306 .strategy = &sysctl_intvec,
310 .ctl_name = CTL_UNNUMBERED,
311 .procname = "sched_features",
312 .data = &sysctl_sched_features,
313 .maxlen = sizeof(unsigned int),
315 .proc_handler = &proc_dointvec,
318 .ctl_name = CTL_UNNUMBERED,
319 .procname = "sched_migration_cost",
320 .data = &sysctl_sched_migration_cost,
321 .maxlen = sizeof(unsigned int),
323 .proc_handler = &proc_dointvec,
326 .ctl_name = CTL_UNNUMBERED,
327 .procname = "sched_nr_migrate",
328 .data = &sysctl_sched_nr_migrate,
329 .maxlen = sizeof(unsigned int),
331 .proc_handler = &proc_dointvec,
334 .ctl_name = CTL_UNNUMBERED,
335 .procname = "sched_time_avg",
336 .data = &sysctl_sched_time_avg,
337 .maxlen = sizeof(unsigned int),
339 .proc_handler = &proc_dointvec,
342 .ctl_name = CTL_UNNUMBERED,
343 .procname = "timer_migration",
344 .data = &sysctl_timer_migration,
345 .maxlen = sizeof(unsigned int),
347 .proc_handler = &proc_dointvec_minmax,
348 .strategy = &sysctl_intvec,
354 .ctl_name = CTL_UNNUMBERED,
355 .procname = "sched_rt_period_us",
356 .data = &sysctl_sched_rt_period,
357 .maxlen = sizeof(unsigned int),
359 .proc_handler = &sched_rt_handler,
362 .ctl_name = CTL_UNNUMBERED,
363 .procname = "sched_rt_runtime_us",
364 .data = &sysctl_sched_rt_runtime,
365 .maxlen = sizeof(int),
367 .proc_handler = &sched_rt_handler,
370 .ctl_name = CTL_UNNUMBERED,
371 .procname = "sched_compat_yield",
372 .data = &sysctl_sched_compat_yield,
373 .maxlen = sizeof(unsigned int),
375 .proc_handler = &proc_dointvec,
377 #ifdef CONFIG_PROVE_LOCKING
379 .ctl_name = CTL_UNNUMBERED,
380 .procname = "prove_locking",
381 .data = &prove_locking,
382 .maxlen = sizeof(int),
384 .proc_handler = &proc_dointvec,
387 #ifdef CONFIG_LOCK_STAT
389 .ctl_name = CTL_UNNUMBERED,
390 .procname = "lock_stat",
392 .maxlen = sizeof(int),
394 .proc_handler = &proc_dointvec,
398 .ctl_name = KERN_PANIC,
400 .data = &panic_timeout,
401 .maxlen = sizeof(int),
403 .proc_handler = &proc_dointvec,
406 .ctl_name = KERN_CORE_USES_PID,
407 .procname = "core_uses_pid",
408 .data = &core_uses_pid,
409 .maxlen = sizeof(int),
411 .proc_handler = &proc_dointvec,
414 .ctl_name = KERN_CORE_PATTERN,
415 .procname = "core_pattern",
416 .data = core_pattern,
417 .maxlen = CORENAME_MAX_SIZE,
419 .proc_handler = &proc_dostring,
420 .strategy = &sysctl_string,
422 #ifdef CONFIG_PROC_SYSCTL
424 .procname = "tainted",
425 .maxlen = sizeof(long),
427 .proc_handler = &proc_taint,
430 #ifdef CONFIG_LATENCYTOP
432 .procname = "latencytop",
433 .data = &latencytop_enabled,
434 .maxlen = sizeof(int),
436 .proc_handler = &proc_dointvec,
439 #ifdef CONFIG_BLK_DEV_INITRD
441 .ctl_name = KERN_REALROOTDEV,
442 .procname = "real-root-dev",
443 .data = &real_root_dev,
444 .maxlen = sizeof(int),
446 .proc_handler = &proc_dointvec,
450 .ctl_name = CTL_UNNUMBERED,
451 .procname = "print-fatal-signals",
452 .data = &print_fatal_signals,
453 .maxlen = sizeof(int),
455 .proc_handler = &proc_dointvec,
459 .ctl_name = KERN_SPARC_REBOOT,
460 .procname = "reboot-cmd",
461 .data = reboot_command,
464 .proc_handler = &proc_dostring,
465 .strategy = &sysctl_string,
468 .ctl_name = KERN_SPARC_STOP_A,
469 .procname = "stop-a",
470 .data = &stop_a_enabled,
471 .maxlen = sizeof (int),
473 .proc_handler = &proc_dointvec,
476 .ctl_name = KERN_SPARC_SCONS_PWROFF,
477 .procname = "scons-poweroff",
478 .data = &scons_pwroff,
479 .maxlen = sizeof (int),
481 .proc_handler = &proc_dointvec,
484 #ifdef CONFIG_SPARC64
486 .ctl_name = CTL_UNNUMBERED,
487 .procname = "tsb-ratio",
488 .data = &sysctl_tsb_ratio,
489 .maxlen = sizeof (int),
491 .proc_handler = &proc_dointvec,
496 .ctl_name = KERN_HPPA_PWRSW,
497 .procname = "soft-power",
498 .data = &pwrsw_enabled,
499 .maxlen = sizeof (int),
501 .proc_handler = &proc_dointvec,
504 .ctl_name = KERN_HPPA_UNALIGNED,
505 .procname = "unaligned-trap",
506 .data = &unaligned_enabled,
507 .maxlen = sizeof (int),
509 .proc_handler = &proc_dointvec,
513 .ctl_name = KERN_CTLALTDEL,
514 .procname = "ctrl-alt-del",
516 .maxlen = sizeof(int),
518 .proc_handler = &proc_dointvec,
520 #ifdef CONFIG_FUNCTION_TRACER
522 .ctl_name = CTL_UNNUMBERED,
523 .procname = "ftrace_enabled",
524 .data = &ftrace_enabled,
525 .maxlen = sizeof(int),
527 .proc_handler = &ftrace_enable_sysctl,
530 #ifdef CONFIG_STACK_TRACER
532 .ctl_name = CTL_UNNUMBERED,
533 .procname = "stack_tracer_enabled",
534 .data = &stack_tracer_enabled,
535 .maxlen = sizeof(int),
537 .proc_handler = &stack_trace_sysctl,
540 #ifdef CONFIG_TRACING
542 .ctl_name = CTL_UNNUMBERED,
543 .procname = "ftrace_dump_on_oops",
544 .data = &ftrace_dump_on_oops,
545 .maxlen = sizeof(int),
547 .proc_handler = &proc_dointvec,
550 #ifdef CONFIG_MODULES
552 .ctl_name = KERN_MODPROBE,
553 .procname = "modprobe",
554 .data = &modprobe_path,
555 .maxlen = KMOD_PATH_LEN,
557 .proc_handler = &proc_dostring,
558 .strategy = &sysctl_string,
561 .ctl_name = CTL_UNNUMBERED,
562 .procname = "modules_disabled",
563 .data = &modules_disabled,
564 .maxlen = sizeof(int),
566 /* only handle a transition from default "0" to "1" */
567 .proc_handler = &proc_dointvec_minmax,
572 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
574 .ctl_name = KERN_HOTPLUG,
575 .procname = "hotplug",
576 .data = &uevent_helper,
577 .maxlen = UEVENT_HELPER_PATH_LEN,
579 .proc_handler = &proc_dostring,
580 .strategy = &sysctl_string,
583 #ifdef CONFIG_CHR_DEV_SG
585 .ctl_name = KERN_SG_BIG_BUFF,
586 .procname = "sg-big-buff",
587 .data = &sg_big_buff,
588 .maxlen = sizeof (int),
590 .proc_handler = &proc_dointvec,
593 #ifdef CONFIG_BSD_PROCESS_ACCT
595 .ctl_name = KERN_ACCT,
598 .maxlen = 3*sizeof(int),
600 .proc_handler = &proc_dointvec,
603 #ifdef CONFIG_MAGIC_SYSRQ
605 .ctl_name = KERN_SYSRQ,
607 .data = &__sysrq_enabled,
608 .maxlen = sizeof (int),
610 .proc_handler = &proc_dointvec,
613 #ifdef CONFIG_PROC_SYSCTL
615 .procname = "cad_pid",
617 .maxlen = sizeof (int),
619 .proc_handler = &proc_do_cad_pid,
623 .ctl_name = KERN_MAX_THREADS,
624 .procname = "threads-max",
625 .data = &max_threads,
626 .maxlen = sizeof(int),
628 .proc_handler = &proc_dointvec,
631 .ctl_name = KERN_RANDOM,
632 .procname = "random",
634 .child = random_table,
637 .ctl_name = KERN_OVERFLOWUID,
638 .procname = "overflowuid",
639 .data = &overflowuid,
640 .maxlen = sizeof(int),
642 .proc_handler = &proc_dointvec_minmax,
643 .strategy = &sysctl_intvec,
644 .extra1 = &minolduid,
645 .extra2 = &maxolduid,
648 .ctl_name = KERN_OVERFLOWGID,
649 .procname = "overflowgid",
650 .data = &overflowgid,
651 .maxlen = sizeof(int),
653 .proc_handler = &proc_dointvec_minmax,
654 .strategy = &sysctl_intvec,
655 .extra1 = &minolduid,
656 .extra2 = &maxolduid,
659 #ifdef CONFIG_MATHEMU
661 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
662 .procname = "ieee_emulation_warnings",
663 .data = &sysctl_ieee_emulation_warnings,
664 .maxlen = sizeof(int),
666 .proc_handler = &proc_dointvec,
670 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
671 .procname = "userprocess_debug",
672 .data = &sysctl_userprocess_debug,
673 .maxlen = sizeof(int),
675 .proc_handler = &proc_dointvec,
679 .ctl_name = KERN_PIDMAX,
680 .procname = "pid_max",
682 .maxlen = sizeof (int),
684 .proc_handler = &proc_dointvec_minmax,
685 .strategy = sysctl_intvec,
686 .extra1 = &pid_max_min,
687 .extra2 = &pid_max_max,
690 .ctl_name = KERN_PANIC_ON_OOPS,
691 .procname = "panic_on_oops",
692 .data = &panic_on_oops,
693 .maxlen = sizeof(int),
695 .proc_handler = &proc_dointvec,
697 #if defined CONFIG_PRINTK
699 .ctl_name = KERN_PRINTK,
700 .procname = "printk",
701 .data = &console_loglevel,
702 .maxlen = 4*sizeof(int),
704 .proc_handler = &proc_dointvec,
707 .ctl_name = KERN_PRINTK_RATELIMIT,
708 .procname = "printk_ratelimit",
709 .data = &printk_ratelimit_state.interval,
710 .maxlen = sizeof(int),
712 .proc_handler = &proc_dointvec_jiffies,
713 .strategy = &sysctl_jiffies,
716 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
717 .procname = "printk_ratelimit_burst",
718 .data = &printk_ratelimit_state.burst,
719 .maxlen = sizeof(int),
721 .proc_handler = &proc_dointvec,
725 .ctl_name = KERN_NGROUPS_MAX,
726 .procname = "ngroups_max",
727 .data = &ngroups_max,
728 .maxlen = sizeof (int),
730 .proc_handler = &proc_dointvec,
732 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
734 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
735 .procname = "unknown_nmi_panic",
736 .data = &unknown_nmi_panic,
737 .maxlen = sizeof (int),
739 .proc_handler = &proc_dointvec,
742 .procname = "nmi_watchdog",
743 .data = &nmi_watchdog_enabled,
744 .maxlen = sizeof (int),
746 .proc_handler = &proc_nmi_enabled,
749 #if defined(CONFIG_X86)
751 .ctl_name = KERN_PANIC_ON_NMI,
752 .procname = "panic_on_unrecovered_nmi",
753 .data = &panic_on_unrecovered_nmi,
754 .maxlen = sizeof(int),
756 .proc_handler = &proc_dointvec,
759 .ctl_name = CTL_UNNUMBERED,
760 .procname = "panic_on_io_nmi",
761 .data = &panic_on_io_nmi,
762 .maxlen = sizeof(int),
764 .proc_handler = &proc_dointvec,
767 .ctl_name = KERN_BOOTLOADER_TYPE,
768 .procname = "bootloader_type",
769 .data = &bootloader_type,
770 .maxlen = sizeof (int),
772 .proc_handler = &proc_dointvec,
775 .ctl_name = CTL_UNNUMBERED,
776 .procname = "bootloader_version",
777 .data = &bootloader_version,
778 .maxlen = sizeof (int),
780 .proc_handler = &proc_dointvec,
783 .ctl_name = CTL_UNNUMBERED,
784 .procname = "kstack_depth_to_print",
785 .data = &kstack_depth_to_print,
786 .maxlen = sizeof(int),
788 .proc_handler = &proc_dointvec,
791 .ctl_name = CTL_UNNUMBERED,
792 .procname = "io_delay_type",
793 .data = &io_delay_type,
794 .maxlen = sizeof(int),
796 .proc_handler = &proc_dointvec,
799 #if defined(CONFIG_MMU)
801 .ctl_name = KERN_RANDOMIZE,
802 .procname = "randomize_va_space",
803 .data = &randomize_va_space,
804 .maxlen = sizeof(int),
806 .proc_handler = &proc_dointvec,
809 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
811 .ctl_name = KERN_SPIN_RETRY,
812 .procname = "spin_retry",
814 .maxlen = sizeof (int),
816 .proc_handler = &proc_dointvec,
819 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
821 .procname = "acpi_video_flags",
822 .data = &acpi_realmode_flags,
823 .maxlen = sizeof (unsigned long),
825 .proc_handler = &proc_doulongvec_minmax,
830 .ctl_name = KERN_IA64_UNALIGNED,
831 .procname = "ignore-unaligned-usertrap",
832 .data = &no_unaligned_warning,
833 .maxlen = sizeof (int),
835 .proc_handler = &proc_dointvec,
838 .ctl_name = CTL_UNNUMBERED,
839 .procname = "unaligned-dump-stack",
840 .data = &unaligned_dump_stack,
841 .maxlen = sizeof (int),
843 .proc_handler = &proc_dointvec,
846 #ifdef CONFIG_DETECT_SOFTLOCKUP
848 .ctl_name = CTL_UNNUMBERED,
849 .procname = "softlockup_panic",
850 .data = &softlockup_panic,
851 .maxlen = sizeof(int),
853 .proc_handler = &proc_dointvec_minmax,
854 .strategy = &sysctl_intvec,
859 .ctl_name = CTL_UNNUMBERED,
860 .procname = "softlockup_thresh",
861 .data = &softlockup_thresh,
862 .maxlen = sizeof(int),
864 .proc_handler = &proc_dosoftlockup_thresh,
865 .strategy = &sysctl_intvec,
870 #ifdef CONFIG_DETECT_HUNG_TASK
872 .ctl_name = CTL_UNNUMBERED,
873 .procname = "hung_task_panic",
874 .data = &sysctl_hung_task_panic,
875 .maxlen = sizeof(int),
877 .proc_handler = &proc_dointvec_minmax,
878 .strategy = &sysctl_intvec,
883 .ctl_name = CTL_UNNUMBERED,
884 .procname = "hung_task_check_count",
885 .data = &sysctl_hung_task_check_count,
886 .maxlen = sizeof(unsigned long),
888 .proc_handler = &proc_doulongvec_minmax,
889 .strategy = &sysctl_intvec,
892 .ctl_name = CTL_UNNUMBERED,
893 .procname = "hung_task_timeout_secs",
894 .data = &sysctl_hung_task_timeout_secs,
895 .maxlen = sizeof(unsigned long),
897 .proc_handler = &proc_dohung_task_timeout_secs,
898 .strategy = &sysctl_intvec,
901 .ctl_name = CTL_UNNUMBERED,
902 .procname = "hung_task_warnings",
903 .data = &sysctl_hung_task_warnings,
904 .maxlen = sizeof(unsigned long),
906 .proc_handler = &proc_doulongvec_minmax,
907 .strategy = &sysctl_intvec,
912 .ctl_name = KERN_COMPAT_LOG,
913 .procname = "compat-log",
915 .maxlen = sizeof (int),
917 .proc_handler = &proc_dointvec,
920 #ifdef CONFIG_RT_MUTEXES
922 .ctl_name = KERN_MAX_LOCK_DEPTH,
923 .procname = "max_lock_depth",
924 .data = &max_lock_depth,
925 .maxlen = sizeof(int),
927 .proc_handler = &proc_dointvec,
931 .ctl_name = CTL_UNNUMBERED,
932 .procname = "poweroff_cmd",
933 .data = &poweroff_cmd,
934 .maxlen = POWEROFF_CMD_PATH_LEN,
936 .proc_handler = &proc_dostring,
937 .strategy = &sysctl_string,
941 .ctl_name = CTL_UNNUMBERED,
944 .child = key_sysctls,
947 #ifdef CONFIG_RCU_TORTURE_TEST
949 .ctl_name = CTL_UNNUMBERED,
950 .procname = "rcutorture_runnable",
951 .data = &rcutorture_runnable,
952 .maxlen = sizeof(int),
954 .proc_handler = &proc_dointvec,
957 #ifdef CONFIG_SLOW_WORK
959 .ctl_name = CTL_UNNUMBERED,
960 .procname = "slow-work",
962 .child = slow_work_sysctls,
965 #ifdef CONFIG_PERF_COUNTERS
967 .ctl_name = CTL_UNNUMBERED,
968 .procname = "perf_counter_paranoid",
969 .data = &sysctl_perf_counter_paranoid,
970 .maxlen = sizeof(sysctl_perf_counter_paranoid),
972 .proc_handler = &proc_dointvec,
975 .ctl_name = CTL_UNNUMBERED,
976 .procname = "perf_counter_mlock_kb",
977 .data = &sysctl_perf_counter_mlock,
978 .maxlen = sizeof(sysctl_perf_counter_mlock),
980 .proc_handler = &proc_dointvec,
983 .ctl_name = CTL_UNNUMBERED,
984 .procname = "perf_counter_max_sample_rate",
985 .data = &sysctl_perf_counter_sample_rate,
986 .maxlen = sizeof(sysctl_perf_counter_sample_rate),
988 .proc_handler = &proc_dointvec,
991 #ifdef CONFIG_KMEMCHECK
993 .ctl_name = CTL_UNNUMBERED,
994 .procname = "kmemcheck",
995 .data = &kmemcheck_enabled,
996 .maxlen = sizeof(int),
998 .proc_handler = &proc_dointvec,
1003 * NOTE: do not add new entries to this table unless you have read
1004 * Documentation/sysctl/ctl_unnumbered.txt
1009 static struct ctl_table vm_table[] = {
1011 .ctl_name = VM_OVERCOMMIT_MEMORY,
1012 .procname = "overcommit_memory",
1013 .data = &sysctl_overcommit_memory,
1014 .maxlen = sizeof(sysctl_overcommit_memory),
1016 .proc_handler = &proc_dointvec,
1019 .ctl_name = VM_PANIC_ON_OOM,
1020 .procname = "panic_on_oom",
1021 .data = &sysctl_panic_on_oom,
1022 .maxlen = sizeof(sysctl_panic_on_oom),
1024 .proc_handler = &proc_dointvec,
1027 .ctl_name = CTL_UNNUMBERED,
1028 .procname = "oom_kill_allocating_task",
1029 .data = &sysctl_oom_kill_allocating_task,
1030 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1032 .proc_handler = &proc_dointvec,
1035 .ctl_name = CTL_UNNUMBERED,
1036 .procname = "oom_dump_tasks",
1037 .data = &sysctl_oom_dump_tasks,
1038 .maxlen = sizeof(sysctl_oom_dump_tasks),
1040 .proc_handler = &proc_dointvec,
1043 .ctl_name = VM_OVERCOMMIT_RATIO,
1044 .procname = "overcommit_ratio",
1045 .data = &sysctl_overcommit_ratio,
1046 .maxlen = sizeof(sysctl_overcommit_ratio),
1048 .proc_handler = &proc_dointvec,
1051 .ctl_name = VM_PAGE_CLUSTER,
1052 .procname = "page-cluster",
1053 .data = &page_cluster,
1054 .maxlen = sizeof(int),
1056 .proc_handler = &proc_dointvec,
1059 .ctl_name = VM_DIRTY_BACKGROUND,
1060 .procname = "dirty_background_ratio",
1061 .data = &dirty_background_ratio,
1062 .maxlen = sizeof(dirty_background_ratio),
1064 .proc_handler = &dirty_background_ratio_handler,
1065 .strategy = &sysctl_intvec,
1067 .extra2 = &one_hundred,
1070 .ctl_name = CTL_UNNUMBERED,
1071 .procname = "dirty_background_bytes",
1072 .data = &dirty_background_bytes,
1073 .maxlen = sizeof(dirty_background_bytes),
1075 .proc_handler = &dirty_background_bytes_handler,
1076 .strategy = &sysctl_intvec,
1080 .ctl_name = VM_DIRTY_RATIO,
1081 .procname = "dirty_ratio",
1082 .data = &vm_dirty_ratio,
1083 .maxlen = sizeof(vm_dirty_ratio),
1085 .proc_handler = &dirty_ratio_handler,
1086 .strategy = &sysctl_intvec,
1088 .extra2 = &one_hundred,
1091 .ctl_name = CTL_UNNUMBERED,
1092 .procname = "dirty_bytes",
1093 .data = &vm_dirty_bytes,
1094 .maxlen = sizeof(vm_dirty_bytes),
1096 .proc_handler = &dirty_bytes_handler,
1097 .strategy = &sysctl_intvec,
1098 .extra1 = &dirty_bytes_min,
1101 .procname = "dirty_writeback_centisecs",
1102 .data = &dirty_writeback_interval,
1103 .maxlen = sizeof(dirty_writeback_interval),
1105 .proc_handler = &dirty_writeback_centisecs_handler,
1108 .procname = "dirty_expire_centisecs",
1109 .data = &dirty_expire_interval,
1110 .maxlen = sizeof(dirty_expire_interval),
1112 .proc_handler = &proc_dointvec,
1115 .ctl_name = VM_NR_PDFLUSH_THREADS,
1116 .procname = "nr_pdflush_threads",
1117 .data = &nr_pdflush_threads,
1118 .maxlen = sizeof nr_pdflush_threads,
1119 .mode = 0444 /* read-only*/,
1120 .proc_handler = &proc_dointvec,
1123 .ctl_name = VM_SWAPPINESS,
1124 .procname = "swappiness",
1125 .data = &vm_swappiness,
1126 .maxlen = sizeof(vm_swappiness),
1128 .proc_handler = &proc_dointvec_minmax,
1129 .strategy = &sysctl_intvec,
1131 .extra2 = &one_hundred,
1133 #ifdef CONFIG_HUGETLB_PAGE
1135 .procname = "nr_hugepages",
1137 .maxlen = sizeof(unsigned long),
1139 .proc_handler = &hugetlb_sysctl_handler,
1140 .extra1 = (void *)&hugetlb_zero,
1141 .extra2 = (void *)&hugetlb_infinity,
1144 .ctl_name = VM_HUGETLB_GROUP,
1145 .procname = "hugetlb_shm_group",
1146 .data = &sysctl_hugetlb_shm_group,
1147 .maxlen = sizeof(gid_t),
1149 .proc_handler = &proc_dointvec,
1152 .ctl_name = CTL_UNNUMBERED,
1153 .procname = "hugepages_treat_as_movable",
1154 .data = &hugepages_treat_as_movable,
1155 .maxlen = sizeof(int),
1157 .proc_handler = &hugetlb_treat_movable_handler,
1160 .ctl_name = CTL_UNNUMBERED,
1161 .procname = "nr_overcommit_hugepages",
1163 .maxlen = sizeof(unsigned long),
1165 .proc_handler = &hugetlb_overcommit_handler,
1166 .extra1 = (void *)&hugetlb_zero,
1167 .extra2 = (void *)&hugetlb_infinity,
1171 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
1172 .procname = "lowmem_reserve_ratio",
1173 .data = &sysctl_lowmem_reserve_ratio,
1174 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1176 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
1177 .strategy = &sysctl_intvec,
1180 .ctl_name = VM_DROP_PAGECACHE,
1181 .procname = "drop_caches",
1182 .data = &sysctl_drop_caches,
1183 .maxlen = sizeof(int),
1185 .proc_handler = drop_caches_sysctl_handler,
1186 .strategy = &sysctl_intvec,
1189 .ctl_name = VM_MIN_FREE_KBYTES,
1190 .procname = "min_free_kbytes",
1191 .data = &min_free_kbytes,
1192 .maxlen = sizeof(min_free_kbytes),
1194 .proc_handler = &min_free_kbytes_sysctl_handler,
1195 .strategy = &sysctl_intvec,
1199 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
1200 .procname = "percpu_pagelist_fraction",
1201 .data = &percpu_pagelist_fraction,
1202 .maxlen = sizeof(percpu_pagelist_fraction),
1204 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
1205 .strategy = &sysctl_intvec,
1206 .extra1 = &min_percpu_pagelist_fract,
1210 .ctl_name = VM_MAX_MAP_COUNT,
1211 .procname = "max_map_count",
1212 .data = &sysctl_max_map_count,
1213 .maxlen = sizeof(sysctl_max_map_count),
1215 .proc_handler = &proc_dointvec
1219 .ctl_name = CTL_UNNUMBERED,
1220 .procname = "nr_trim_pages",
1221 .data = &sysctl_nr_trim_pages,
1222 .maxlen = sizeof(sysctl_nr_trim_pages),
1224 .proc_handler = &proc_dointvec_minmax,
1225 .strategy = &sysctl_intvec,
1230 .ctl_name = VM_LAPTOP_MODE,
1231 .procname = "laptop_mode",
1232 .data = &laptop_mode,
1233 .maxlen = sizeof(laptop_mode),
1235 .proc_handler = &proc_dointvec_jiffies,
1236 .strategy = &sysctl_jiffies,
1239 .ctl_name = VM_BLOCK_DUMP,
1240 .procname = "block_dump",
1241 .data = &block_dump,
1242 .maxlen = sizeof(block_dump),
1244 .proc_handler = &proc_dointvec,
1245 .strategy = &sysctl_intvec,
1249 .ctl_name = VM_VFS_CACHE_PRESSURE,
1250 .procname = "vfs_cache_pressure",
1251 .data = &sysctl_vfs_cache_pressure,
1252 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1254 .proc_handler = &proc_dointvec,
1255 .strategy = &sysctl_intvec,
1258 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1260 .ctl_name = VM_LEGACY_VA_LAYOUT,
1261 .procname = "legacy_va_layout",
1262 .data = &sysctl_legacy_va_layout,
1263 .maxlen = sizeof(sysctl_legacy_va_layout),
1265 .proc_handler = &proc_dointvec,
1266 .strategy = &sysctl_intvec,
1272 .ctl_name = VM_ZONE_RECLAIM_MODE,
1273 .procname = "zone_reclaim_mode",
1274 .data = &zone_reclaim_mode,
1275 .maxlen = sizeof(zone_reclaim_mode),
1277 .proc_handler = &proc_dointvec,
1278 .strategy = &sysctl_intvec,
1282 .ctl_name = VM_MIN_UNMAPPED,
1283 .procname = "min_unmapped_ratio",
1284 .data = &sysctl_min_unmapped_ratio,
1285 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1287 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1288 .strategy = &sysctl_intvec,
1290 .extra2 = &one_hundred,
1293 .ctl_name = VM_MIN_SLAB,
1294 .procname = "min_slab_ratio",
1295 .data = &sysctl_min_slab_ratio,
1296 .maxlen = sizeof(sysctl_min_slab_ratio),
1298 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1299 .strategy = &sysctl_intvec,
1301 .extra2 = &one_hundred,
1306 .ctl_name = CTL_UNNUMBERED,
1307 .procname = "stat_interval",
1308 .data = &sysctl_stat_interval,
1309 .maxlen = sizeof(sysctl_stat_interval),
1311 .proc_handler = &proc_dointvec_jiffies,
1312 .strategy = &sysctl_jiffies,
1316 .ctl_name = CTL_UNNUMBERED,
1317 .procname = "mmap_min_addr",
1318 .data = &dac_mmap_min_addr,
1319 .maxlen = sizeof(unsigned long),
1321 .proc_handler = &mmap_min_addr_handler,
1325 .ctl_name = CTL_UNNUMBERED,
1326 .procname = "numa_zonelist_order",
1327 .data = &numa_zonelist_order,
1328 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1330 .proc_handler = &numa_zonelist_order_handler,
1331 .strategy = &sysctl_string,
1334 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1335 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1337 .ctl_name = VM_VDSO_ENABLED,
1338 .procname = "vdso_enabled",
1339 .data = &vdso_enabled,
1340 .maxlen = sizeof(vdso_enabled),
1342 .proc_handler = &proc_dointvec,
1343 .strategy = &sysctl_intvec,
1347 #ifdef CONFIG_HIGHMEM
1349 .ctl_name = CTL_UNNUMBERED,
1350 .procname = "highmem_is_dirtyable",
1351 .data = &vm_highmem_is_dirtyable,
1352 .maxlen = sizeof(vm_highmem_is_dirtyable),
1354 .proc_handler = &proc_dointvec_minmax,
1355 .strategy = &sysctl_intvec,
1361 .ctl_name = CTL_UNNUMBERED,
1362 .procname = "scan_unevictable_pages",
1363 .data = &scan_unevictable_pages,
1364 .maxlen = sizeof(scan_unevictable_pages),
1366 .proc_handler = &scan_unevictable_handler,
1369 * NOTE: do not add new entries to this table unless you have read
1370 * Documentation/sysctl/ctl_unnumbered.txt
1375 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1376 static struct ctl_table binfmt_misc_table[] = {
1381 static struct ctl_table fs_table[] = {
1383 .ctl_name = FS_NRINODE,
1384 .procname = "inode-nr",
1385 .data = &inodes_stat,
1386 .maxlen = 2*sizeof(int),
1388 .proc_handler = &proc_dointvec,
1391 .ctl_name = FS_STATINODE,
1392 .procname = "inode-state",
1393 .data = &inodes_stat,
1394 .maxlen = 7*sizeof(int),
1396 .proc_handler = &proc_dointvec,
1399 .procname = "file-nr",
1400 .data = &files_stat,
1401 .maxlen = 3*sizeof(int),
1403 .proc_handler = &proc_nr_files,
1406 .ctl_name = FS_MAXFILE,
1407 .procname = "file-max",
1408 .data = &files_stat.max_files,
1409 .maxlen = sizeof(int),
1411 .proc_handler = &proc_dointvec,
1414 .ctl_name = CTL_UNNUMBERED,
1415 .procname = "nr_open",
1416 .data = &sysctl_nr_open,
1417 .maxlen = sizeof(int),
1419 .proc_handler = &proc_dointvec_minmax,
1420 .extra1 = &sysctl_nr_open_min,
1421 .extra2 = &sysctl_nr_open_max,
1424 .ctl_name = FS_DENTRY,
1425 .procname = "dentry-state",
1426 .data = &dentry_stat,
1427 .maxlen = 6*sizeof(int),
1429 .proc_handler = &proc_dointvec,
1432 .ctl_name = FS_OVERFLOWUID,
1433 .procname = "overflowuid",
1434 .data = &fs_overflowuid,
1435 .maxlen = sizeof(int),
1437 .proc_handler = &proc_dointvec_minmax,
1438 .strategy = &sysctl_intvec,
1439 .extra1 = &minolduid,
1440 .extra2 = &maxolduid,
1443 .ctl_name = FS_OVERFLOWGID,
1444 .procname = "overflowgid",
1445 .data = &fs_overflowgid,
1446 .maxlen = sizeof(int),
1448 .proc_handler = &proc_dointvec_minmax,
1449 .strategy = &sysctl_intvec,
1450 .extra1 = &minolduid,
1451 .extra2 = &maxolduid,
1453 #ifdef CONFIG_FILE_LOCKING
1455 .ctl_name = FS_LEASES,
1456 .procname = "leases-enable",
1457 .data = &leases_enable,
1458 .maxlen = sizeof(int),
1460 .proc_handler = &proc_dointvec,
1463 #ifdef CONFIG_DNOTIFY
1465 .ctl_name = FS_DIR_NOTIFY,
1466 .procname = "dir-notify-enable",
1467 .data = &dir_notify_enable,
1468 .maxlen = sizeof(int),
1470 .proc_handler = &proc_dointvec,
1474 #ifdef CONFIG_FILE_LOCKING
1476 .ctl_name = FS_LEASE_TIME,
1477 .procname = "lease-break-time",
1478 .data = &lease_break_time,
1479 .maxlen = sizeof(int),
1481 .proc_handler = &proc_dointvec,
1486 .procname = "aio-nr",
1488 .maxlen = sizeof(aio_nr),
1490 .proc_handler = &proc_doulongvec_minmax,
1493 .procname = "aio-max-nr",
1494 .data = &aio_max_nr,
1495 .maxlen = sizeof(aio_max_nr),
1497 .proc_handler = &proc_doulongvec_minmax,
1499 #endif /* CONFIG_AIO */
1500 #ifdef CONFIG_INOTIFY_USER
1502 .ctl_name = FS_INOTIFY,
1503 .procname = "inotify",
1505 .child = inotify_table,
1510 .procname = "epoll",
1512 .child = epoll_table,
1517 .ctl_name = KERN_SETUID_DUMPABLE,
1518 .procname = "suid_dumpable",
1519 .data = &suid_dumpable,
1520 .maxlen = sizeof(int),
1522 .proc_handler = &proc_dointvec_minmax,
1523 .strategy = &sysctl_intvec,
1527 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1529 .ctl_name = CTL_UNNUMBERED,
1530 .procname = "binfmt_misc",
1532 .child = binfmt_misc_table,
1536 * NOTE: do not add new entries to this table unless you have read
1537 * Documentation/sysctl/ctl_unnumbered.txt
1542 static struct ctl_table debug_table[] = {
1543 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1545 .ctl_name = CTL_UNNUMBERED,
1546 .procname = "exception-trace",
1547 .data = &show_unhandled_signals,
1548 .maxlen = sizeof(int),
1550 .proc_handler = proc_dointvec
1556 static struct ctl_table dev_table[] = {
1560 static DEFINE_SPINLOCK(sysctl_lock);
1562 /* called under sysctl_lock */
1563 static int use_table(struct ctl_table_header *p)
1565 if (unlikely(p->unregistering))
1571 /* called under sysctl_lock */
1572 static void unuse_table(struct ctl_table_header *p)
1575 if (unlikely(p->unregistering))
1576 complete(p->unregistering);
1579 /* called under sysctl_lock, will reacquire if has to wait */
1580 static void start_unregistering(struct ctl_table_header *p)
1583 * if p->used is 0, nobody will ever touch that entry again;
1584 * we'll eliminate all paths to it before dropping sysctl_lock
1586 if (unlikely(p->used)) {
1587 struct completion wait;
1588 init_completion(&wait);
1589 p->unregistering = &wait;
1590 spin_unlock(&sysctl_lock);
1591 wait_for_completion(&wait);
1592 spin_lock(&sysctl_lock);
1594 /* anything non-NULL; we'll never dereference it */
1595 p->unregistering = ERR_PTR(-EINVAL);
1598 * do not remove from the list until nobody holds it; walking the
1599 * list in do_sysctl() relies on that.
1601 list_del_init(&p->ctl_entry);
1604 void sysctl_head_get(struct ctl_table_header *head)
1606 spin_lock(&sysctl_lock);
1608 spin_unlock(&sysctl_lock);
1611 void sysctl_head_put(struct ctl_table_header *head)
1613 spin_lock(&sysctl_lock);
1616 spin_unlock(&sysctl_lock);
1619 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1623 spin_lock(&sysctl_lock);
1624 if (!use_table(head))
1625 head = ERR_PTR(-ENOENT);
1626 spin_unlock(&sysctl_lock);
1630 void sysctl_head_finish(struct ctl_table_header *head)
1634 spin_lock(&sysctl_lock);
1636 spin_unlock(&sysctl_lock);
1639 static struct ctl_table_set *
1640 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1642 struct ctl_table_set *set = &root->default_set;
1644 set = root->lookup(root, namespaces);
1648 static struct list_head *
1649 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1651 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1655 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1656 struct ctl_table_header *prev)
1658 struct ctl_table_root *root;
1659 struct list_head *header_list;
1660 struct ctl_table_header *head;
1661 struct list_head *tmp;
1663 spin_lock(&sysctl_lock);
1666 tmp = &prev->ctl_entry;
1670 tmp = &root_table_header.ctl_entry;
1672 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1674 if (!use_table(head))
1676 spin_unlock(&sysctl_lock);
1681 header_list = lookup_header_list(root, namespaces);
1682 if (tmp != header_list)
1686 root = list_entry(root->root_list.next,
1687 struct ctl_table_root, root_list);
1688 if (root == &sysctl_table_root)
1690 header_list = lookup_header_list(root, namespaces);
1691 } while (list_empty(header_list));
1692 tmp = header_list->next;
1695 spin_unlock(&sysctl_lock);
1699 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1701 return __sysctl_head_next(current->nsproxy, prev);
1704 void register_sysctl_root(struct ctl_table_root *root)
1706 spin_lock(&sysctl_lock);
1707 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1708 spin_unlock(&sysctl_lock);
1711 #ifdef CONFIG_SYSCTL_SYSCALL
1712 /* Perform the actual read/write of a sysctl table entry. */
1713 static int do_sysctl_strategy(struct ctl_table_root *root,
1714 struct ctl_table *table,
1715 void __user *oldval, size_t __user *oldlenp,
1716 void __user *newval, size_t newlen)
1724 if (sysctl_perm(root, table, op))
1727 if (table->strategy) {
1728 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1735 /* If there is no strategy routine, or if the strategy returns
1736 * zero, proceed with automatic r/w */
1737 if (table->data && table->maxlen) {
1738 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1745 static int parse_table(int __user *name, int nlen,
1746 void __user *oldval, size_t __user *oldlenp,
1747 void __user *newval, size_t newlen,
1748 struct ctl_table_root *root,
1749 struct ctl_table *table)
1755 if (get_user(n, name))
1757 for ( ; table->ctl_name || table->procname; table++) {
1758 if (!table->ctl_name)
1760 if (n == table->ctl_name) {
1763 if (sysctl_perm(root, table, MAY_EXEC))
1767 table = table->child;
1770 error = do_sysctl_strategy(root, table,
1779 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1780 void __user *newval, size_t newlen)
1782 struct ctl_table_header *head;
1783 int error = -ENOTDIR;
1785 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1789 if (!oldlenp || get_user(old_len, oldlenp))
1793 for (head = sysctl_head_next(NULL); head;
1794 head = sysctl_head_next(head)) {
1795 error = parse_table(name, nlen, oldval, oldlenp,
1797 head->root, head->ctl_table);
1798 if (error != -ENOTDIR) {
1799 sysctl_head_finish(head);
1806 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1808 struct __sysctl_args tmp;
1811 if (copy_from_user(&tmp, args, sizeof(tmp)))
1814 error = deprecated_sysctl_warning(&tmp);
1819 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1820 tmp.newval, tmp.newlen);
1825 #endif /* CONFIG_SYSCTL_SYSCALL */
1828 * sysctl_perm does NOT grant the superuser all rights automatically, because
1829 * some sysctl variables are readonly even to root.
1832 static int test_perm(int mode, int op)
1834 if (!current_euid())
1836 else if (in_egroup_p(0))
1838 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1843 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1848 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1852 if (root->permissions)
1853 mode = root->permissions(root, current->nsproxy, table);
1857 return test_perm(mode, op);
1860 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1862 for (; table->ctl_name || table->procname; table++) {
1863 table->parent = parent;
1865 sysctl_set_parent(table, table->child);
1869 static __init int sysctl_init(void)
1871 sysctl_set_parent(NULL, root_table);
1872 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1875 err = sysctl_check_table(current->nsproxy, root_table);
1881 core_initcall(sysctl_init);
1883 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1884 struct ctl_table *table)
1886 struct ctl_table *p;
1887 const char *s = branch->procname;
1889 /* branch should have named subdirectory as its first element */
1890 if (!s || !branch->child)
1893 /* ... and nothing else */
1894 if (branch[1].procname || branch[1].ctl_name)
1897 /* table should contain subdirectory with the same name */
1898 for (p = table; p->procname || p->ctl_name; p++) {
1901 if (p->procname && strcmp(p->procname, s) == 0)
1907 /* see if attaching q to p would be an improvement */
1908 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1910 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1911 struct ctl_table *next;
1913 int not_in_parent = !p->attached_by;
1915 while ((next = is_branch_in(by, to)) != NULL) {
1916 if (by == q->attached_by)
1918 if (to == p->attached_by)
1924 if (is_better && not_in_parent) {
1925 q->attached_by = by;
1926 q->attached_to = to;
1932 * __register_sysctl_paths - register a sysctl hierarchy
1933 * @root: List of sysctl headers to register on
1934 * @namespaces: Data to compute which lists of sysctl entries are visible
1935 * @path: The path to the directory the sysctl table is in.
1936 * @table: the top-level table structure
1938 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1939 * array. A completely 0 filled entry terminates the table.
1941 * The members of the &struct ctl_table structure are used as follows:
1943 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1944 * must be unique within that level of sysctl
1946 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1947 * enter a sysctl file
1949 * data - a pointer to data for use by proc_handler
1951 * maxlen - the maximum size in bytes of the data
1953 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1955 * child - a pointer to the child sysctl table if this entry is a directory, or
1958 * proc_handler - the text handler routine (described below)
1960 * strategy - the strategy routine (described below)
1962 * de - for internal use by the sysctl routines
1964 * extra1, extra2 - extra pointers usable by the proc handler routines
1966 * Leaf nodes in the sysctl tree will be represented by a single file
1967 * under /proc; non-leaf nodes will be represented by directories.
1969 * sysctl(2) can automatically manage read and write requests through
1970 * the sysctl table. The data and maxlen fields of the ctl_table
1971 * struct enable minimal validation of the values being written to be
1972 * performed, and the mode field allows minimal authentication.
1974 * More sophisticated management can be enabled by the provision of a
1975 * strategy routine with the table entry. This will be called before
1976 * any automatic read or write of the data is performed.
1978 * The strategy routine may return
1980 * < 0 - Error occurred (error is passed to user process)
1982 * 0 - OK - proceed with automatic read or write.
1984 * > 0 - OK - read or write has been done by the strategy routine, so
1985 * return immediately.
1987 * There must be a proc_handler routine for any terminal nodes
1988 * mirrored under /proc/sys (non-terminals are handled by a built-in
1989 * directory handler). Several default handlers are available to
1990 * cover common cases -
1992 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1993 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1994 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1996 * It is the handler's job to read the input buffer from user memory
1997 * and process it. The handler should return 0 on success.
1999 * This routine returns %NULL on a failure to register, and a pointer
2000 * to the table header on success.
2002 struct ctl_table_header *__register_sysctl_paths(
2003 struct ctl_table_root *root,
2004 struct nsproxy *namespaces,
2005 const struct ctl_path *path, struct ctl_table *table)
2007 struct ctl_table_header *header;
2008 struct ctl_table *new, **prevp;
2009 unsigned int n, npath;
2010 struct ctl_table_set *set;
2012 /* Count the path components */
2013 for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
2017 * For each path component, allocate a 2-element ctl_table array.
2018 * The first array element will be filled with the sysctl entry
2019 * for this, the second will be the sentinel (ctl_name == 0).
2021 * We allocate everything in one go so that we don't have to
2022 * worry about freeing additional memory in unregister_sysctl_table.
2024 header = kzalloc(sizeof(struct ctl_table_header) +
2025 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
2029 new = (struct ctl_table *) (header + 1);
2031 /* Now connect the dots */
2032 prevp = &header->ctl_table;
2033 for (n = 0; n < npath; ++n, ++path) {
2034 /* Copy the procname */
2035 new->procname = path->procname;
2036 new->ctl_name = path->ctl_name;
2040 prevp = &new->child;
2045 header->ctl_table_arg = table;
2047 INIT_LIST_HEAD(&header->ctl_entry);
2049 header->unregistering = NULL;
2050 header->root = root;
2051 sysctl_set_parent(NULL, header->ctl_table);
2053 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
2054 if (sysctl_check_table(namespaces, header->ctl_table)) {
2059 spin_lock(&sysctl_lock);
2060 header->set = lookup_header_set(root, namespaces);
2061 header->attached_by = header->ctl_table;
2062 header->attached_to = root_table;
2063 header->parent = &root_table_header;
2064 for (set = header->set; set; set = set->parent) {
2065 struct ctl_table_header *p;
2066 list_for_each_entry(p, &set->list, ctl_entry) {
2067 if (p->unregistering)
2069 try_attach(p, header);
2072 header->parent->count++;
2073 list_add_tail(&header->ctl_entry, &header->set->list);
2074 spin_unlock(&sysctl_lock);
2080 * register_sysctl_table_path - register a sysctl table hierarchy
2081 * @path: The path to the directory the sysctl table is in.
2082 * @table: the top-level table structure
2084 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2085 * array. A completely 0 filled entry terminates the table.
2087 * See __register_sysctl_paths for more details.
2089 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2090 struct ctl_table *table)
2092 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
2097 * register_sysctl_table - register a sysctl table hierarchy
2098 * @table: the top-level table structure
2100 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
2101 * array. A completely 0 filled entry terminates the table.
2103 * See register_sysctl_paths for more details.
2105 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2107 static const struct ctl_path null_path[] = { {} };
2109 return register_sysctl_paths(null_path, table);
2113 * unregister_sysctl_table - unregister a sysctl table hierarchy
2114 * @header: the header returned from register_sysctl_table
2116 * Unregisters the sysctl table and all children. proc entries may not
2117 * actually be removed until they are no longer used by anyone.
2119 void unregister_sysctl_table(struct ctl_table_header * header)
2126 spin_lock(&sysctl_lock);
2127 start_unregistering(header);
2128 if (!--header->parent->count) {
2130 kfree(header->parent);
2132 if (!--header->count)
2134 spin_unlock(&sysctl_lock);
2137 int sysctl_is_seen(struct ctl_table_header *p)
2139 struct ctl_table_set *set = p->set;
2141 spin_lock(&sysctl_lock);
2142 if (p->unregistering)
2144 else if (!set->is_seen)
2147 res = set->is_seen(set);
2148 spin_unlock(&sysctl_lock);
2152 void setup_sysctl_set(struct ctl_table_set *p,
2153 struct ctl_table_set *parent,
2154 int (*is_seen)(struct ctl_table_set *))
2156 INIT_LIST_HEAD(&p->list);
2157 p->parent = parent ? parent : &sysctl_table_root.default_set;
2158 p->is_seen = is_seen;
2161 #else /* !CONFIG_SYSCTL */
2162 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2167 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2168 struct ctl_table *table)
2173 void unregister_sysctl_table(struct ctl_table_header * table)
2177 void setup_sysctl_set(struct ctl_table_set *p,
2178 struct ctl_table_set *parent,
2179 int (*is_seen)(struct ctl_table_set *))
2183 void sysctl_head_put(struct ctl_table_header *head)
2187 #endif /* CONFIG_SYSCTL */
2193 #ifdef CONFIG_PROC_SYSCTL
2195 static int _proc_do_string(void* data, int maxlen, int write,
2196 struct file *filp, void __user *buffer,
2197 size_t *lenp, loff_t *ppos)
2203 if (!data || !maxlen || !*lenp) {
2211 while (len < *lenp) {
2212 if (get_user(c, p++))
2214 if (c == 0 || c == '\n')
2220 if(copy_from_user(data, buffer, len))
2222 ((char *) data)[len] = 0;
2240 if(copy_to_user(buffer, data, len))
2243 if(put_user('\n', ((char __user *) buffer) + len))
2254 * proc_dostring - read a string sysctl
2255 * @table: the sysctl table
2256 * @write: %TRUE if this is a write to the sysctl file
2257 * @filp: the file structure
2258 * @buffer: the user buffer
2259 * @lenp: the size of the user buffer
2260 * @ppos: file position
2262 * Reads/writes a string from/to the user buffer. If the kernel
2263 * buffer provided is not large enough to hold the string, the
2264 * string is truncated. The copied string is %NULL-terminated.
2265 * If the string is being read by the user process, it is copied
2266 * and a newline '\n' is added. It is truncated if the buffer is
2269 * Returns 0 on success.
2271 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2272 void __user *buffer, size_t *lenp, loff_t *ppos)
2274 return _proc_do_string(table->data, table->maxlen, write, filp,
2275 buffer, lenp, ppos);
2279 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2281 int write, void *data)
2284 *valp = *negp ? -*lvalp : *lvalp;
2289 *lvalp = (unsigned long)-val;
2292 *lvalp = (unsigned long)val;
2298 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2299 int write, struct file *filp, void __user *buffer,
2300 size_t *lenp, loff_t *ppos,
2301 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2302 int write, void *data),
2305 #define TMPBUFLEN 21
2306 int *i, vleft, first = 1, neg;
2310 char buf[TMPBUFLEN], *p;
2311 char __user *s = buffer;
2313 if (!tbl_data || !table->maxlen || !*lenp ||
2314 (*ppos && !write)) {
2319 i = (int *) tbl_data;
2320 vleft = table->maxlen / sizeof(*i);
2324 conv = do_proc_dointvec_conv;
2326 for (; left && vleft--; i++, first=0) {
2341 if (len > sizeof(buf) - 1)
2342 len = sizeof(buf) - 1;
2343 if (copy_from_user(buf, s, len))
2347 if (*p == '-' && left > 1) {
2351 if (*p < '0' || *p > '9')
2354 lval = simple_strtoul(p, &p, 0);
2357 if ((len < left) && *p && !isspace(*p))
2362 if (conv(&neg, &lval, i, 1, data))
2369 if (conv(&neg, &lval, i, 0, data))
2372 sprintf(p, "%s%lu", neg ? "-" : "", lval);
2376 if(copy_to_user(s, buf, len))
2383 if (!write && !first && left) {
2384 if(put_user('\n', s))
2391 if (get_user(c, s++))
2406 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2407 void __user *buffer, size_t *lenp, loff_t *ppos,
2408 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2409 int write, void *data),
2412 return __do_proc_dointvec(table->data, table, write, filp,
2413 buffer, lenp, ppos, conv, data);
2417 * proc_dointvec - read a vector of integers
2418 * @table: the sysctl table
2419 * @write: %TRUE if this is a write to the sysctl file
2420 * @filp: the file structure
2421 * @buffer: the user buffer
2422 * @lenp: the size of the user buffer
2423 * @ppos: file position
2425 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2426 * values from/to the user buffer, treated as an ASCII string.
2428 * Returns 0 on success.
2430 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2431 void __user *buffer, size_t *lenp, loff_t *ppos)
2433 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2438 * Taint values can only be increased
2439 * This means we can safely use a temporary.
2441 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2442 void __user *buffer, size_t *lenp, loff_t *ppos)
2445 unsigned long tmptaint = get_taint();
2448 if (write && !capable(CAP_SYS_ADMIN))
2453 err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2459 * Poor man's atomic or. Not worth adding a primitive
2460 * to everyone's atomic.h for this
2463 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2464 if ((tmptaint >> i) & 1)
2472 struct do_proc_dointvec_minmax_conv_param {
2477 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2479 int write, void *data)
2481 struct do_proc_dointvec_minmax_conv_param *param = data;
2483 int val = *negp ? -*lvalp : *lvalp;
2484 if ((param->min && *param->min > val) ||
2485 (param->max && *param->max < val))
2492 *lvalp = (unsigned long)-val;
2495 *lvalp = (unsigned long)val;
2502 * proc_dointvec_minmax - read a vector of integers with min/max values
2503 * @table: the sysctl table
2504 * @write: %TRUE if this is a write to the sysctl file
2505 * @filp: the file structure
2506 * @buffer: the user buffer
2507 * @lenp: the size of the user buffer
2508 * @ppos: file position
2510 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2511 * values from/to the user buffer, treated as an ASCII string.
2513 * This routine will ensure the values are within the range specified by
2514 * table->extra1 (min) and table->extra2 (max).
2516 * Returns 0 on success.
2518 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2519 void __user *buffer, size_t *lenp, loff_t *ppos)
2521 struct do_proc_dointvec_minmax_conv_param param = {
2522 .min = (int *) table->extra1,
2523 .max = (int *) table->extra2,
2525 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2526 do_proc_dointvec_minmax_conv, ¶m);
2529 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2531 void __user *buffer,
2532 size_t *lenp, loff_t *ppos,
2533 unsigned long convmul,
2534 unsigned long convdiv)
2536 #define TMPBUFLEN 21
2537 unsigned long *i, *min, *max, val;
2538 int vleft, first=1, neg;
2540 char buf[TMPBUFLEN], *p;
2541 char __user *s = buffer;
2543 if (!data || !table->maxlen || !*lenp ||
2544 (*ppos && !write)) {
2549 i = (unsigned long *) data;
2550 min = (unsigned long *) table->extra1;
2551 max = (unsigned long *) table->extra2;
2552 vleft = table->maxlen / sizeof(unsigned long);
2555 for (; left && vleft--; i++, min++, max++, first=0) {
2570 if (len > TMPBUFLEN-1)
2572 if (copy_from_user(buf, s, len))
2576 if (*p == '-' && left > 1) {
2580 if (*p < '0' || *p > '9')
2582 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2584 if ((len < left) && *p && !isspace(*p))
2593 if ((min && val < *min) || (max && val > *max))
2600 sprintf(p, "%lu", convdiv * (*i) / convmul);
2604 if(copy_to_user(s, buf, len))
2611 if (!write && !first && left) {
2612 if(put_user('\n', s))
2619 if (get_user(c, s++))
2634 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2636 void __user *buffer,
2637 size_t *lenp, loff_t *ppos,
2638 unsigned long convmul,
2639 unsigned long convdiv)
2641 return __do_proc_doulongvec_minmax(table->data, table, write,
2642 filp, buffer, lenp, ppos, convmul, convdiv);
2646 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2647 * @table: the sysctl table
2648 * @write: %TRUE if this is a write to the sysctl file
2649 * @filp: the file structure
2650 * @buffer: the user buffer
2651 * @lenp: the size of the user buffer
2652 * @ppos: file position
2654 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2655 * values from/to the user buffer, treated as an ASCII string.
2657 * This routine will ensure the values are within the range specified by
2658 * table->extra1 (min) and table->extra2 (max).
2660 * Returns 0 on success.
2662 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2663 void __user *buffer, size_t *lenp, loff_t *ppos)
2665 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2669 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2670 * @table: the sysctl table
2671 * @write: %TRUE if this is a write to the sysctl file
2672 * @filp: the file structure
2673 * @buffer: the user buffer
2674 * @lenp: the size of the user buffer
2675 * @ppos: file position
2677 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2678 * values from/to the user buffer, treated as an ASCII string. The values
2679 * are treated as milliseconds, and converted to jiffies when they are stored.
2681 * This routine will ensure the values are within the range specified by
2682 * table->extra1 (min) and table->extra2 (max).
2684 * Returns 0 on success.
2686 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2688 void __user *buffer,
2689 size_t *lenp, loff_t *ppos)
2691 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2692 lenp, ppos, HZ, 1000l);
2696 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2698 int write, void *data)
2701 if (*lvalp > LONG_MAX / HZ)
2703 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2709 lval = (unsigned long)-val;
2712 lval = (unsigned long)val;
2719 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2721 int write, void *data)
2724 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2726 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2732 lval = (unsigned long)-val;
2735 lval = (unsigned long)val;
2737 *lvalp = jiffies_to_clock_t(lval);
2742 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2744 int write, void *data)
2747 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2753 lval = (unsigned long)-val;
2756 lval = (unsigned long)val;
2758 *lvalp = jiffies_to_msecs(lval);
2764 * proc_dointvec_jiffies - read a vector of integers as seconds
2765 * @table: the sysctl table
2766 * @write: %TRUE if this is a write to the sysctl file
2767 * @filp: the file structure
2768 * @buffer: the user buffer
2769 * @lenp: the size of the user buffer
2770 * @ppos: file position
2772 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2773 * values from/to the user buffer, treated as an ASCII string.
2774 * The values read are assumed to be in seconds, and are converted into
2777 * Returns 0 on success.
2779 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2780 void __user *buffer, size_t *lenp, loff_t *ppos)
2782 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2783 do_proc_dointvec_jiffies_conv,NULL);
2787 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2788 * @table: the sysctl table
2789 * @write: %TRUE if this is a write to the sysctl file
2790 * @filp: the file structure
2791 * @buffer: the user buffer
2792 * @lenp: the size of the user buffer
2793 * @ppos: pointer to the file position
2795 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2796 * values from/to the user buffer, treated as an ASCII string.
2797 * The values read are assumed to be in 1/USER_HZ seconds, and
2798 * are converted into jiffies.
2800 * Returns 0 on success.
2802 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2803 void __user *buffer, size_t *lenp, loff_t *ppos)
2805 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2806 do_proc_dointvec_userhz_jiffies_conv,NULL);
2810 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2811 * @table: the sysctl table
2812 * @write: %TRUE if this is a write to the sysctl file
2813 * @filp: the file structure
2814 * @buffer: the user buffer
2815 * @lenp: the size of the user buffer
2816 * @ppos: file position
2817 * @ppos: the current position in the file
2819 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2820 * values from/to the user buffer, treated as an ASCII string.
2821 * The values read are assumed to be in 1/1000 seconds, and
2822 * are converted into jiffies.
2824 * Returns 0 on success.
2826 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2827 void __user *buffer, size_t *lenp, loff_t *ppos)
2829 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2830 do_proc_dointvec_ms_jiffies_conv, NULL);
2833 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2834 void __user *buffer, size_t *lenp, loff_t *ppos)
2836 struct pid *new_pid;
2840 tmp = pid_vnr(cad_pid);
2842 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2843 lenp, ppos, NULL, NULL);
2847 new_pid = find_get_pid(tmp);
2851 put_pid(xchg(&cad_pid, new_pid));
2855 #else /* CONFIG_PROC_FS */
2857 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2858 void __user *buffer, size_t *lenp, loff_t *ppos)
2863 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2864 void __user *buffer, size_t *lenp, loff_t *ppos)
2869 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2870 void __user *buffer, size_t *lenp, loff_t *ppos)
2875 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2876 void __user *buffer, size_t *lenp, loff_t *ppos)
2881 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2882 void __user *buffer, size_t *lenp, loff_t *ppos)
2887 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2888 void __user *buffer, size_t *lenp, loff_t *ppos)
2893 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2894 void __user *buffer, size_t *lenp, loff_t *ppos)
2899 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2901 void __user *buffer,
2902 size_t *lenp, loff_t *ppos)
2908 #endif /* CONFIG_PROC_FS */
2911 #ifdef CONFIG_SYSCTL_SYSCALL
2913 * General sysctl support routines
2916 /* The generic sysctl data routine (used if no strategy routine supplied) */
2917 int sysctl_data(struct ctl_table *table,
2918 void __user *oldval, size_t __user *oldlenp,
2919 void __user *newval, size_t newlen)
2923 /* Get out of I don't have a variable */
2924 if (!table->data || !table->maxlen)
2927 if (oldval && oldlenp) {
2928 if (get_user(len, oldlenp))
2931 if (len > table->maxlen)
2932 len = table->maxlen;
2933 if (copy_to_user(oldval, table->data, len))
2935 if (put_user(len, oldlenp))
2940 if (newval && newlen) {
2941 if (newlen > table->maxlen)
2942 newlen = table->maxlen;
2944 if (copy_from_user(table->data, newval, newlen))
2950 /* The generic string strategy routine: */
2951 int sysctl_string(struct ctl_table *table,
2952 void __user *oldval, size_t __user *oldlenp,
2953 void __user *newval, size_t newlen)
2955 if (!table->data || !table->maxlen)
2958 if (oldval && oldlenp) {
2960 if (get_user(bufsize, oldlenp))
2963 size_t len = strlen(table->data), copied;
2965 /* This shouldn't trigger for a well-formed sysctl */
2966 if (len > table->maxlen)
2967 len = table->maxlen;
2969 /* Copy up to a max of bufsize-1 bytes of the string */
2970 copied = (len >= bufsize) ? bufsize - 1 : len;
2972 if (copy_to_user(oldval, table->data, copied) ||
2973 put_user(0, (char __user *)(oldval + copied)))
2975 if (put_user(len, oldlenp))
2979 if (newval && newlen) {
2980 size_t len = newlen;
2981 if (len > table->maxlen)
2982 len = table->maxlen;
2983 if(copy_from_user(table->data, newval, len))
2985 if (len == table->maxlen)
2987 ((char *) table->data)[len] = 0;
2993 * This function makes sure that all of the integers in the vector
2994 * are between the minimum and maximum values given in the arrays
2995 * table->extra1 and table->extra2, respectively.
2997 int sysctl_intvec(struct ctl_table *table,
2998 void __user *oldval, size_t __user *oldlenp,
2999 void __user *newval, size_t newlen)
3002 if (newval && newlen) {
3003 int __user *vec = (int __user *) newval;
3004 int *min = (int *) table->extra1;
3005 int *max = (int *) table->extra2;
3009 if (newlen % sizeof(int) != 0)
3012 if (!table->extra1 && !table->extra2)
3015 if (newlen > table->maxlen)
3016 newlen = table->maxlen;
3017 length = newlen / sizeof(int);
3019 for (i = 0; i < length; i++) {
3021 if (get_user(value, vec + i))
3023 if (min && value < min[i])
3025 if (max && value > max[i])
3032 /* Strategy function to convert jiffies to seconds */
3033 int sysctl_jiffies(struct ctl_table *table,
3034 void __user *oldval, size_t __user *oldlenp,
3035 void __user *newval, size_t newlen)
3037 if (oldval && oldlenp) {
3040 if (get_user(olen, oldlenp))
3045 if (olen < sizeof(int))
3048 val = *(int *)(table->data) / HZ;
3049 if (put_user(val, (int __user *)oldval))
3051 if (put_user(sizeof(int), oldlenp))
3055 if (newval && newlen) {
3057 if (newlen != sizeof(int))
3059 if (get_user(new, (int __user *)newval))
3061 *(int *)(table->data) = new*HZ;
3066 /* Strategy function to convert jiffies to seconds */
3067 int sysctl_ms_jiffies(struct ctl_table *table,
3068 void __user *oldval, size_t __user *oldlenp,
3069 void __user *newval, size_t newlen)
3071 if (oldval && oldlenp) {
3074 if (get_user(olen, oldlenp))
3079 if (olen < sizeof(int))
3082 val = jiffies_to_msecs(*(int *)(table->data));
3083 if (put_user(val, (int __user *)oldval))
3085 if (put_user(sizeof(int), oldlenp))
3089 if (newval && newlen) {
3091 if (newlen != sizeof(int))
3093 if (get_user(new, (int __user *)newval))
3095 *(int *)(table->data) = msecs_to_jiffies(new);
3102 #else /* CONFIG_SYSCTL_SYSCALL */
3105 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3107 struct __sysctl_args tmp;
3110 if (copy_from_user(&tmp, args, sizeof(tmp)))
3113 error = deprecated_sysctl_warning(&tmp);
3115 /* If no error reading the parameters then just -ENOSYS ... */
3122 int sysctl_data(struct ctl_table *table,
3123 void __user *oldval, size_t __user *oldlenp,
3124 void __user *newval, size_t newlen)
3129 int sysctl_string(struct ctl_table *table,
3130 void __user *oldval, size_t __user *oldlenp,
3131 void __user *newval, size_t newlen)
3136 int sysctl_intvec(struct ctl_table *table,
3137 void __user *oldval, size_t __user *oldlenp,
3138 void __user *newval, size_t newlen)
3143 int sysctl_jiffies(struct ctl_table *table,
3144 void __user *oldval, size_t __user *oldlenp,
3145 void __user *newval, size_t newlen)
3150 int sysctl_ms_jiffies(struct ctl_table *table,
3151 void __user *oldval, size_t __user *oldlenp,
3152 void __user *newval, size_t newlen)
3157 #endif /* CONFIG_SYSCTL_SYSCALL */
3159 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3161 static int msg_count;
3162 int name[CTL_MAXNAME];
3165 /* Check args->nlen. */
3166 if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3169 /* Read in the sysctl name for better debug message logging */
3170 for (i = 0; i < args->nlen; i++)
3171 if (get_user(name[i], args->name + i))
3174 /* Ignore accesses to kernel.version */
3175 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3178 if (msg_count < 5) {
3181 "warning: process `%s' used the deprecated sysctl "
3182 "system call with ", current->comm);
3183 for (i = 0; i < args->nlen; i++)
3184 printk("%d.", name[i]);
3191 * No sense putting this after each symbol definition, twice,
3192 * exception granted :-)
3194 EXPORT_SYMBOL(proc_dointvec);
3195 EXPORT_SYMBOL(proc_dointvec_jiffies);
3196 EXPORT_SYMBOL(proc_dointvec_minmax);
3197 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3198 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3199 EXPORT_SYMBOL(proc_dostring);
3200 EXPORT_SYMBOL(proc_doulongvec_minmax);
3201 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3202 EXPORT_SYMBOL(register_sysctl_table);
3203 EXPORT_SYMBOL(register_sysctl_paths);
3204 EXPORT_SYMBOL(sysctl_intvec);
3205 EXPORT_SYMBOL(sysctl_jiffies);
3206 EXPORT_SYMBOL(sysctl_ms_jiffies);
3207 EXPORT_SYMBOL(sysctl_string);
3208 EXPORT_SYMBOL(sysctl_data);
3209 EXPORT_SYMBOL(unregister_sysctl_table);