2 * sysctl.c: General linux system control interface
4 * Begun 24 March 1995, Stephen Tweedie
5 * Added /proc support, Dec 1995
6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9 * Dynamic registration fixes, Stephen Tweedie.
10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
21 #include <linux/module.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/security.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/smp_lock.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/initrd.h>
41 #include <linux/key.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/vmstat.h>
47 #include <linux/nfs_fs.h>
48 #include <linux/acpi.h>
49 #include <linux/reboot.h>
50 #include <linux/ftrace.h>
52 #include <asm/uaccess.h>
53 #include <asm/processor.h>
57 #include <asm/stacktrace.h>
61 static int deprecated_sysctl_warning(struct __sysctl_args *args);
63 #if defined(CONFIG_SYSCTL)
65 /* External variables not in a header file. */
67 extern int print_fatal_signals;
68 extern int sysctl_overcommit_memory;
69 extern int sysctl_overcommit_ratio;
70 extern int sysctl_panic_on_oom;
71 extern int sysctl_oom_kill_allocating_task;
72 extern int sysctl_oom_dump_tasks;
73 extern int max_threads;
74 extern int core_uses_pid;
75 extern int suid_dumpable;
76 extern char core_pattern[];
78 extern int min_free_kbytes;
79 extern int pid_max_min, pid_max_max;
80 extern int sysctl_drop_caches;
81 extern int percpu_pagelist_fraction;
82 extern int compat_log;
83 extern int latencytop_enabled;
84 extern int sysctl_nr_open_min, sysctl_nr_open_max;
86 extern int sysctl_nr_trim_pages;
88 #ifdef CONFIG_RCU_TORTURE_TEST
89 extern int rcutorture_runnable;
90 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
92 /* Constants used for minimum and maximum */
93 #ifdef CONFIG_DETECT_SOFTLOCKUP
94 static int sixty = 60;
95 static int neg_one = -1;
98 #if defined(CONFIG_MMU) && defined(CONFIG_FILE_LOCKING)
104 static unsigned long one_ul = 1;
105 static int one_hundred = 100;
107 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
108 static int maxolduid = 65535;
109 static int minolduid;
110 static int min_percpu_pagelist_fract = 8;
112 static int ngroups_max = NGROUPS_MAX;
114 #ifdef CONFIG_MODULES
115 extern char modprobe_path[];
117 #ifdef CONFIG_CHR_DEV_SG
118 extern int sg_big_buff;
122 #include <asm/system.h>
125 #ifdef CONFIG_SPARC64
126 extern int sysctl_tsb_ratio;
130 extern int pwrsw_enabled;
131 extern int unaligned_enabled;
135 #ifdef CONFIG_MATHEMU
136 extern int sysctl_ieee_emulation_warnings;
138 extern int sysctl_userprocess_debug;
139 extern int spin_retry;
142 #ifdef CONFIG_BSD_PROCESS_ACCT
143 extern int acct_parm[];
147 extern int no_unaligned_warning;
148 extern int unaligned_dump_stack;
151 #ifdef CONFIG_RT_MUTEXES
152 extern int max_lock_depth;
155 #ifdef CONFIG_PROC_SYSCTL
156 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
157 void __user *buffer, size_t *lenp, loff_t *ppos);
158 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
159 void __user *buffer, size_t *lenp, loff_t *ppos);
162 static struct ctl_table root_table[];
163 static struct ctl_table_root sysctl_table_root;
164 static struct ctl_table_header root_table_header = {
166 .ctl_table = root_table,
167 .ctl_entry = LIST_HEAD_INIT(sysctl_table_root.default_set.list),
168 .root = &sysctl_table_root,
169 .set = &sysctl_table_root.default_set,
171 static struct ctl_table_root sysctl_table_root = {
172 .root_list = LIST_HEAD_INIT(sysctl_table_root.root_list),
173 .default_set.list = LIST_HEAD_INIT(root_table_header.ctl_entry),
176 static struct ctl_table kern_table[];
177 static struct ctl_table vm_table[];
178 static struct ctl_table fs_table[];
179 static struct ctl_table debug_table[];
180 static struct ctl_table dev_table[];
181 extern struct ctl_table random_table[];
182 #ifdef CONFIG_INOTIFY_USER
183 extern struct ctl_table inotify_table[];
186 extern struct ctl_table epoll_table[];
189 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
190 int sysctl_legacy_va_layout;
193 extern int prove_locking;
194 extern int lock_stat;
196 /* The default sysctl tables: */
198 static struct ctl_table root_table[] = {
200 .ctl_name = CTL_KERN,
201 .procname = "kernel",
218 .ctl_name = CTL_DEBUG,
221 .child = debug_table,
230 * NOTE: do not add new entries to this table unless you have read
231 * Documentation/sysctl/ctl_unnumbered.txt
236 #ifdef CONFIG_SCHED_DEBUG
237 static int min_sched_granularity_ns = 100000; /* 100 usecs */
238 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
239 static int min_wakeup_granularity_ns; /* 0 usecs */
240 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
243 static struct ctl_table kern_table[] = {
244 #ifdef CONFIG_SCHED_DEBUG
246 .ctl_name = CTL_UNNUMBERED,
247 .procname = "sched_min_granularity_ns",
248 .data = &sysctl_sched_min_granularity,
249 .maxlen = sizeof(unsigned int),
251 .proc_handler = &sched_nr_latency_handler,
252 .strategy = &sysctl_intvec,
253 .extra1 = &min_sched_granularity_ns,
254 .extra2 = &max_sched_granularity_ns,
257 .ctl_name = CTL_UNNUMBERED,
258 .procname = "sched_latency_ns",
259 .data = &sysctl_sched_latency,
260 .maxlen = sizeof(unsigned int),
262 .proc_handler = &sched_nr_latency_handler,
263 .strategy = &sysctl_intvec,
264 .extra1 = &min_sched_granularity_ns,
265 .extra2 = &max_sched_granularity_ns,
268 .ctl_name = CTL_UNNUMBERED,
269 .procname = "sched_wakeup_granularity_ns",
270 .data = &sysctl_sched_wakeup_granularity,
271 .maxlen = sizeof(unsigned int),
273 .proc_handler = &proc_dointvec_minmax,
274 .strategy = &sysctl_intvec,
275 .extra1 = &min_wakeup_granularity_ns,
276 .extra2 = &max_wakeup_granularity_ns,
279 .ctl_name = CTL_UNNUMBERED,
280 .procname = "sched_shares_ratelimit",
281 .data = &sysctl_sched_shares_ratelimit,
282 .maxlen = sizeof(unsigned int),
284 .proc_handler = &proc_dointvec,
287 .ctl_name = CTL_UNNUMBERED,
288 .procname = "sched_shares_thresh",
289 .data = &sysctl_sched_shares_thresh,
290 .maxlen = sizeof(unsigned int),
292 .proc_handler = &proc_dointvec_minmax,
293 .strategy = &sysctl_intvec,
297 .ctl_name = CTL_UNNUMBERED,
298 .procname = "sched_child_runs_first",
299 .data = &sysctl_sched_child_runs_first,
300 .maxlen = sizeof(unsigned int),
302 .proc_handler = &proc_dointvec,
305 .ctl_name = CTL_UNNUMBERED,
306 .procname = "sched_features",
307 .data = &sysctl_sched_features,
308 .maxlen = sizeof(unsigned int),
310 .proc_handler = &proc_dointvec,
313 .ctl_name = CTL_UNNUMBERED,
314 .procname = "sched_migration_cost",
315 .data = &sysctl_sched_migration_cost,
316 .maxlen = sizeof(unsigned int),
318 .proc_handler = &proc_dointvec,
321 .ctl_name = CTL_UNNUMBERED,
322 .procname = "sched_nr_migrate",
323 .data = &sysctl_sched_nr_migrate,
324 .maxlen = sizeof(unsigned int),
326 .proc_handler = &proc_dointvec,
330 .ctl_name = CTL_UNNUMBERED,
331 .procname = "sched_rt_period_us",
332 .data = &sysctl_sched_rt_period,
333 .maxlen = sizeof(unsigned int),
335 .proc_handler = &sched_rt_handler,
338 .ctl_name = CTL_UNNUMBERED,
339 .procname = "sched_rt_runtime_us",
340 .data = &sysctl_sched_rt_runtime,
341 .maxlen = sizeof(int),
343 .proc_handler = &sched_rt_handler,
346 .ctl_name = CTL_UNNUMBERED,
347 .procname = "sched_compat_yield",
348 .data = &sysctl_sched_compat_yield,
349 .maxlen = sizeof(unsigned int),
351 .proc_handler = &proc_dointvec,
353 #ifdef CONFIG_PROVE_LOCKING
355 .ctl_name = CTL_UNNUMBERED,
356 .procname = "prove_locking",
357 .data = &prove_locking,
358 .maxlen = sizeof(int),
360 .proc_handler = &proc_dointvec,
363 #ifdef CONFIG_LOCK_STAT
365 .ctl_name = CTL_UNNUMBERED,
366 .procname = "lock_stat",
368 .maxlen = sizeof(int),
370 .proc_handler = &proc_dointvec,
374 .ctl_name = KERN_PANIC,
376 .data = &panic_timeout,
377 .maxlen = sizeof(int),
379 .proc_handler = &proc_dointvec,
382 .ctl_name = KERN_CORE_USES_PID,
383 .procname = "core_uses_pid",
384 .data = &core_uses_pid,
385 .maxlen = sizeof(int),
387 .proc_handler = &proc_dointvec,
390 .ctl_name = KERN_CORE_PATTERN,
391 .procname = "core_pattern",
392 .data = core_pattern,
393 .maxlen = CORENAME_MAX_SIZE,
395 .proc_handler = &proc_dostring,
396 .strategy = &sysctl_string,
398 #ifdef CONFIG_PROC_SYSCTL
400 .procname = "tainted",
401 .maxlen = sizeof(long),
403 .proc_handler = &proc_taint,
406 #ifdef CONFIG_LATENCYTOP
408 .procname = "latencytop",
409 .data = &latencytop_enabled,
410 .maxlen = sizeof(int),
412 .proc_handler = &proc_dointvec,
415 #ifdef CONFIG_BLK_DEV_INITRD
417 .ctl_name = KERN_REALROOTDEV,
418 .procname = "real-root-dev",
419 .data = &real_root_dev,
420 .maxlen = sizeof(int),
422 .proc_handler = &proc_dointvec,
426 .ctl_name = CTL_UNNUMBERED,
427 .procname = "print-fatal-signals",
428 .data = &print_fatal_signals,
429 .maxlen = sizeof(int),
431 .proc_handler = &proc_dointvec,
435 .ctl_name = KERN_SPARC_REBOOT,
436 .procname = "reboot-cmd",
437 .data = reboot_command,
440 .proc_handler = &proc_dostring,
441 .strategy = &sysctl_string,
444 .ctl_name = KERN_SPARC_STOP_A,
445 .procname = "stop-a",
446 .data = &stop_a_enabled,
447 .maxlen = sizeof (int),
449 .proc_handler = &proc_dointvec,
452 .ctl_name = KERN_SPARC_SCONS_PWROFF,
453 .procname = "scons-poweroff",
454 .data = &scons_pwroff,
455 .maxlen = sizeof (int),
457 .proc_handler = &proc_dointvec,
460 #ifdef CONFIG_SPARC64
462 .ctl_name = CTL_UNNUMBERED,
463 .procname = "tsb-ratio",
464 .data = &sysctl_tsb_ratio,
465 .maxlen = sizeof (int),
467 .proc_handler = &proc_dointvec,
472 .ctl_name = KERN_HPPA_PWRSW,
473 .procname = "soft-power",
474 .data = &pwrsw_enabled,
475 .maxlen = sizeof (int),
477 .proc_handler = &proc_dointvec,
480 .ctl_name = KERN_HPPA_UNALIGNED,
481 .procname = "unaligned-trap",
482 .data = &unaligned_enabled,
483 .maxlen = sizeof (int),
485 .proc_handler = &proc_dointvec,
489 .ctl_name = KERN_CTLALTDEL,
490 .procname = "ctrl-alt-del",
492 .maxlen = sizeof(int),
494 .proc_handler = &proc_dointvec,
496 #ifdef CONFIG_FUNCTION_TRACER
498 .ctl_name = CTL_UNNUMBERED,
499 .procname = "ftrace_enabled",
500 .data = &ftrace_enabled,
501 .maxlen = sizeof(int),
503 .proc_handler = &ftrace_enable_sysctl,
506 #ifdef CONFIG_STACK_TRACER
508 .ctl_name = CTL_UNNUMBERED,
509 .procname = "stack_tracer_enabled",
510 .data = &stack_tracer_enabled,
511 .maxlen = sizeof(int),
513 .proc_handler = &stack_trace_sysctl,
516 #ifdef CONFIG_TRACING
518 .ctl_name = CTL_UNNUMBERED,
519 .procname = "ftrace_dump_on_oops",
520 .data = &ftrace_dump_on_oops,
521 .maxlen = sizeof(int),
523 .proc_handler = &proc_dointvec,
526 #ifdef CONFIG_MODULES
528 .ctl_name = KERN_MODPROBE,
529 .procname = "modprobe",
530 .data = &modprobe_path,
531 .maxlen = KMOD_PATH_LEN,
533 .proc_handler = &proc_dostring,
534 .strategy = &sysctl_string,
537 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
539 .ctl_name = KERN_HOTPLUG,
540 .procname = "hotplug",
541 .data = &uevent_helper,
542 .maxlen = UEVENT_HELPER_PATH_LEN,
544 .proc_handler = &proc_dostring,
545 .strategy = &sysctl_string,
548 #ifdef CONFIG_CHR_DEV_SG
550 .ctl_name = KERN_SG_BIG_BUFF,
551 .procname = "sg-big-buff",
552 .data = &sg_big_buff,
553 .maxlen = sizeof (int),
555 .proc_handler = &proc_dointvec,
558 #ifdef CONFIG_BSD_PROCESS_ACCT
560 .ctl_name = KERN_ACCT,
563 .maxlen = 3*sizeof(int),
565 .proc_handler = &proc_dointvec,
568 #ifdef CONFIG_MAGIC_SYSRQ
570 .ctl_name = KERN_SYSRQ,
572 .data = &__sysrq_enabled,
573 .maxlen = sizeof (int),
575 .proc_handler = &proc_dointvec,
578 #ifdef CONFIG_PROC_SYSCTL
580 .procname = "cad_pid",
582 .maxlen = sizeof (int),
584 .proc_handler = &proc_do_cad_pid,
588 .ctl_name = KERN_MAX_THREADS,
589 .procname = "threads-max",
590 .data = &max_threads,
591 .maxlen = sizeof(int),
593 .proc_handler = &proc_dointvec,
596 .ctl_name = KERN_RANDOM,
597 .procname = "random",
599 .child = random_table,
602 .ctl_name = KERN_OVERFLOWUID,
603 .procname = "overflowuid",
604 .data = &overflowuid,
605 .maxlen = sizeof(int),
607 .proc_handler = &proc_dointvec_minmax,
608 .strategy = &sysctl_intvec,
609 .extra1 = &minolduid,
610 .extra2 = &maxolduid,
613 .ctl_name = KERN_OVERFLOWGID,
614 .procname = "overflowgid",
615 .data = &overflowgid,
616 .maxlen = sizeof(int),
618 .proc_handler = &proc_dointvec_minmax,
619 .strategy = &sysctl_intvec,
620 .extra1 = &minolduid,
621 .extra2 = &maxolduid,
624 #ifdef CONFIG_MATHEMU
626 .ctl_name = KERN_IEEE_EMULATION_WARNINGS,
627 .procname = "ieee_emulation_warnings",
628 .data = &sysctl_ieee_emulation_warnings,
629 .maxlen = sizeof(int),
631 .proc_handler = &proc_dointvec,
635 .ctl_name = KERN_S390_USER_DEBUG_LOGGING,
636 .procname = "userprocess_debug",
637 .data = &sysctl_userprocess_debug,
638 .maxlen = sizeof(int),
640 .proc_handler = &proc_dointvec,
644 .ctl_name = KERN_PIDMAX,
645 .procname = "pid_max",
647 .maxlen = sizeof (int),
649 .proc_handler = &proc_dointvec_minmax,
650 .strategy = sysctl_intvec,
651 .extra1 = &pid_max_min,
652 .extra2 = &pid_max_max,
655 .ctl_name = KERN_PANIC_ON_OOPS,
656 .procname = "panic_on_oops",
657 .data = &panic_on_oops,
658 .maxlen = sizeof(int),
660 .proc_handler = &proc_dointvec,
662 #if defined CONFIG_PRINTK
664 .ctl_name = KERN_PRINTK,
665 .procname = "printk",
666 .data = &console_loglevel,
667 .maxlen = 4*sizeof(int),
669 .proc_handler = &proc_dointvec,
672 .ctl_name = KERN_PRINTK_RATELIMIT,
673 .procname = "printk_ratelimit",
674 .data = &printk_ratelimit_state.interval,
675 .maxlen = sizeof(int),
677 .proc_handler = &proc_dointvec_jiffies,
678 .strategy = &sysctl_jiffies,
681 .ctl_name = KERN_PRINTK_RATELIMIT_BURST,
682 .procname = "printk_ratelimit_burst",
683 .data = &printk_ratelimit_state.burst,
684 .maxlen = sizeof(int),
686 .proc_handler = &proc_dointvec,
690 .ctl_name = KERN_NGROUPS_MAX,
691 .procname = "ngroups_max",
692 .data = &ngroups_max,
693 .maxlen = sizeof (int),
695 .proc_handler = &proc_dointvec,
697 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
699 .ctl_name = KERN_UNKNOWN_NMI_PANIC,
700 .procname = "unknown_nmi_panic",
701 .data = &unknown_nmi_panic,
702 .maxlen = sizeof (int),
704 .proc_handler = &proc_dointvec,
707 .procname = "nmi_watchdog",
708 .data = &nmi_watchdog_enabled,
709 .maxlen = sizeof (int),
711 .proc_handler = &proc_nmi_enabled,
714 #if defined(CONFIG_X86)
716 .ctl_name = KERN_PANIC_ON_NMI,
717 .procname = "panic_on_unrecovered_nmi",
718 .data = &panic_on_unrecovered_nmi,
719 .maxlen = sizeof(int),
721 .proc_handler = &proc_dointvec,
724 .ctl_name = KERN_BOOTLOADER_TYPE,
725 .procname = "bootloader_type",
726 .data = &bootloader_type,
727 .maxlen = sizeof (int),
729 .proc_handler = &proc_dointvec,
732 .ctl_name = CTL_UNNUMBERED,
733 .procname = "kstack_depth_to_print",
734 .data = &kstack_depth_to_print,
735 .maxlen = sizeof(int),
737 .proc_handler = &proc_dointvec,
740 .ctl_name = CTL_UNNUMBERED,
741 .procname = "io_delay_type",
742 .data = &io_delay_type,
743 .maxlen = sizeof(int),
745 .proc_handler = &proc_dointvec,
748 #if defined(CONFIG_MMU)
750 .ctl_name = KERN_RANDOMIZE,
751 .procname = "randomize_va_space",
752 .data = &randomize_va_space,
753 .maxlen = sizeof(int),
755 .proc_handler = &proc_dointvec,
758 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
760 .ctl_name = KERN_SPIN_RETRY,
761 .procname = "spin_retry",
763 .maxlen = sizeof (int),
765 .proc_handler = &proc_dointvec,
768 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
770 .procname = "acpi_video_flags",
771 .data = &acpi_realmode_flags,
772 .maxlen = sizeof (unsigned long),
774 .proc_handler = &proc_doulongvec_minmax,
779 .ctl_name = KERN_IA64_UNALIGNED,
780 .procname = "ignore-unaligned-usertrap",
781 .data = &no_unaligned_warning,
782 .maxlen = sizeof (int),
784 .proc_handler = &proc_dointvec,
787 .ctl_name = CTL_UNNUMBERED,
788 .procname = "unaligned-dump-stack",
789 .data = &unaligned_dump_stack,
790 .maxlen = sizeof (int),
792 .proc_handler = &proc_dointvec,
795 #ifdef CONFIG_DETECT_SOFTLOCKUP
797 .ctl_name = CTL_UNNUMBERED,
798 .procname = "softlockup_panic",
799 .data = &softlockup_panic,
800 .maxlen = sizeof(int),
802 .proc_handler = &proc_dointvec_minmax,
803 .strategy = &sysctl_intvec,
808 .ctl_name = CTL_UNNUMBERED,
809 .procname = "softlockup_thresh",
810 .data = &softlockup_thresh,
811 .maxlen = sizeof(int),
813 .proc_handler = &proc_dosoftlockup_thresh,
814 .strategy = &sysctl_intvec,
819 .ctl_name = CTL_UNNUMBERED,
820 .procname = "hung_task_check_count",
821 .data = &sysctl_hung_task_check_count,
822 .maxlen = sizeof(unsigned long),
824 .proc_handler = &proc_doulongvec_minmax,
825 .strategy = &sysctl_intvec,
828 .ctl_name = CTL_UNNUMBERED,
829 .procname = "hung_task_timeout_secs",
830 .data = &sysctl_hung_task_timeout_secs,
831 .maxlen = sizeof(unsigned long),
833 .proc_handler = &proc_doulongvec_minmax,
834 .strategy = &sysctl_intvec,
837 .ctl_name = CTL_UNNUMBERED,
838 .procname = "hung_task_warnings",
839 .data = &sysctl_hung_task_warnings,
840 .maxlen = sizeof(unsigned long),
842 .proc_handler = &proc_doulongvec_minmax,
843 .strategy = &sysctl_intvec,
848 .ctl_name = KERN_COMPAT_LOG,
849 .procname = "compat-log",
851 .maxlen = sizeof (int),
853 .proc_handler = &proc_dointvec,
856 #ifdef CONFIG_RT_MUTEXES
858 .ctl_name = KERN_MAX_LOCK_DEPTH,
859 .procname = "max_lock_depth",
860 .data = &max_lock_depth,
861 .maxlen = sizeof(int),
863 .proc_handler = &proc_dointvec,
867 .ctl_name = CTL_UNNUMBERED,
868 .procname = "poweroff_cmd",
869 .data = &poweroff_cmd,
870 .maxlen = POWEROFF_CMD_PATH_LEN,
872 .proc_handler = &proc_dostring,
873 .strategy = &sysctl_string,
877 .ctl_name = CTL_UNNUMBERED,
880 .child = key_sysctls,
883 #ifdef CONFIG_RCU_TORTURE_TEST
885 .ctl_name = CTL_UNNUMBERED,
886 .procname = "rcutorture_runnable",
887 .data = &rcutorture_runnable,
888 .maxlen = sizeof(int),
890 .proc_handler = &proc_dointvec,
893 #ifdef CONFIG_UNEVICTABLE_LRU
895 .ctl_name = CTL_UNNUMBERED,
896 .procname = "scan_unevictable_pages",
897 .data = &scan_unevictable_pages,
898 .maxlen = sizeof(scan_unevictable_pages),
900 .proc_handler = &scan_unevictable_handler,
904 * NOTE: do not add new entries to this table unless you have read
905 * Documentation/sysctl/ctl_unnumbered.txt
910 static struct ctl_table vm_table[] = {
912 .ctl_name = VM_OVERCOMMIT_MEMORY,
913 .procname = "overcommit_memory",
914 .data = &sysctl_overcommit_memory,
915 .maxlen = sizeof(sysctl_overcommit_memory),
917 .proc_handler = &proc_dointvec,
920 .ctl_name = VM_PANIC_ON_OOM,
921 .procname = "panic_on_oom",
922 .data = &sysctl_panic_on_oom,
923 .maxlen = sizeof(sysctl_panic_on_oom),
925 .proc_handler = &proc_dointvec,
928 .ctl_name = CTL_UNNUMBERED,
929 .procname = "oom_kill_allocating_task",
930 .data = &sysctl_oom_kill_allocating_task,
931 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
933 .proc_handler = &proc_dointvec,
936 .ctl_name = CTL_UNNUMBERED,
937 .procname = "oom_dump_tasks",
938 .data = &sysctl_oom_dump_tasks,
939 .maxlen = sizeof(sysctl_oom_dump_tasks),
941 .proc_handler = &proc_dointvec,
944 .ctl_name = VM_OVERCOMMIT_RATIO,
945 .procname = "overcommit_ratio",
946 .data = &sysctl_overcommit_ratio,
947 .maxlen = sizeof(sysctl_overcommit_ratio),
949 .proc_handler = &proc_dointvec,
952 .ctl_name = VM_PAGE_CLUSTER,
953 .procname = "page-cluster",
954 .data = &page_cluster,
955 .maxlen = sizeof(int),
957 .proc_handler = &proc_dointvec,
960 .ctl_name = VM_DIRTY_BACKGROUND,
961 .procname = "dirty_background_ratio",
962 .data = &dirty_background_ratio,
963 .maxlen = sizeof(dirty_background_ratio),
965 .proc_handler = &dirty_background_ratio_handler,
966 .strategy = &sysctl_intvec,
968 .extra2 = &one_hundred,
971 .ctl_name = CTL_UNNUMBERED,
972 .procname = "dirty_background_bytes",
973 .data = &dirty_background_bytes,
974 .maxlen = sizeof(dirty_background_bytes),
976 .proc_handler = &dirty_background_bytes_handler,
977 .strategy = &sysctl_intvec,
981 .ctl_name = VM_DIRTY_RATIO,
982 .procname = "dirty_ratio",
983 .data = &vm_dirty_ratio,
984 .maxlen = sizeof(vm_dirty_ratio),
986 .proc_handler = &dirty_ratio_handler,
987 .strategy = &sysctl_intvec,
989 .extra2 = &one_hundred,
992 .ctl_name = CTL_UNNUMBERED,
993 .procname = "dirty_bytes",
994 .data = &vm_dirty_bytes,
995 .maxlen = sizeof(vm_dirty_bytes),
997 .proc_handler = &dirty_bytes_handler,
998 .strategy = &sysctl_intvec,
1002 .procname = "dirty_writeback_centisecs",
1003 .data = &dirty_writeback_interval,
1004 .maxlen = sizeof(dirty_writeback_interval),
1006 .proc_handler = &dirty_writeback_centisecs_handler,
1009 .procname = "dirty_expire_centisecs",
1010 .data = &dirty_expire_interval,
1011 .maxlen = sizeof(dirty_expire_interval),
1013 .proc_handler = &proc_dointvec_userhz_jiffies,
1016 .ctl_name = VM_NR_PDFLUSH_THREADS,
1017 .procname = "nr_pdflush_threads",
1018 .data = &nr_pdflush_threads,
1019 .maxlen = sizeof nr_pdflush_threads,
1020 .mode = 0444 /* read-only*/,
1021 .proc_handler = &proc_dointvec,
1024 .ctl_name = VM_SWAPPINESS,
1025 .procname = "swappiness",
1026 .data = &vm_swappiness,
1027 .maxlen = sizeof(vm_swappiness),
1029 .proc_handler = &proc_dointvec_minmax,
1030 .strategy = &sysctl_intvec,
1032 .extra2 = &one_hundred,
1034 #ifdef CONFIG_HUGETLB_PAGE
1036 .procname = "nr_hugepages",
1038 .maxlen = sizeof(unsigned long),
1040 .proc_handler = &hugetlb_sysctl_handler,
1041 .extra1 = (void *)&hugetlb_zero,
1042 .extra2 = (void *)&hugetlb_infinity,
1045 .ctl_name = VM_HUGETLB_GROUP,
1046 .procname = "hugetlb_shm_group",
1047 .data = &sysctl_hugetlb_shm_group,
1048 .maxlen = sizeof(gid_t),
1050 .proc_handler = &proc_dointvec,
1053 .ctl_name = CTL_UNNUMBERED,
1054 .procname = "hugepages_treat_as_movable",
1055 .data = &hugepages_treat_as_movable,
1056 .maxlen = sizeof(int),
1058 .proc_handler = &hugetlb_treat_movable_handler,
1061 .ctl_name = CTL_UNNUMBERED,
1062 .procname = "nr_overcommit_hugepages",
1064 .maxlen = sizeof(unsigned long),
1066 .proc_handler = &hugetlb_overcommit_handler,
1067 .extra1 = (void *)&hugetlb_zero,
1068 .extra2 = (void *)&hugetlb_infinity,
1072 .ctl_name = VM_LOWMEM_RESERVE_RATIO,
1073 .procname = "lowmem_reserve_ratio",
1074 .data = &sysctl_lowmem_reserve_ratio,
1075 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1077 .proc_handler = &lowmem_reserve_ratio_sysctl_handler,
1078 .strategy = &sysctl_intvec,
1081 .ctl_name = VM_DROP_PAGECACHE,
1082 .procname = "drop_caches",
1083 .data = &sysctl_drop_caches,
1084 .maxlen = sizeof(int),
1086 .proc_handler = drop_caches_sysctl_handler,
1087 .strategy = &sysctl_intvec,
1090 .ctl_name = VM_MIN_FREE_KBYTES,
1091 .procname = "min_free_kbytes",
1092 .data = &min_free_kbytes,
1093 .maxlen = sizeof(min_free_kbytes),
1095 .proc_handler = &min_free_kbytes_sysctl_handler,
1096 .strategy = &sysctl_intvec,
1100 .ctl_name = VM_PERCPU_PAGELIST_FRACTION,
1101 .procname = "percpu_pagelist_fraction",
1102 .data = &percpu_pagelist_fraction,
1103 .maxlen = sizeof(percpu_pagelist_fraction),
1105 .proc_handler = &percpu_pagelist_fraction_sysctl_handler,
1106 .strategy = &sysctl_intvec,
1107 .extra1 = &min_percpu_pagelist_fract,
1111 .ctl_name = VM_MAX_MAP_COUNT,
1112 .procname = "max_map_count",
1113 .data = &sysctl_max_map_count,
1114 .maxlen = sizeof(sysctl_max_map_count),
1116 .proc_handler = &proc_dointvec
1120 .ctl_name = CTL_UNNUMBERED,
1121 .procname = "nr_trim_pages",
1122 .data = &sysctl_nr_trim_pages,
1123 .maxlen = sizeof(sysctl_nr_trim_pages),
1125 .proc_handler = &proc_dointvec_minmax,
1126 .strategy = &sysctl_intvec,
1131 .ctl_name = VM_LAPTOP_MODE,
1132 .procname = "laptop_mode",
1133 .data = &laptop_mode,
1134 .maxlen = sizeof(laptop_mode),
1136 .proc_handler = &proc_dointvec_jiffies,
1137 .strategy = &sysctl_jiffies,
1140 .ctl_name = VM_BLOCK_DUMP,
1141 .procname = "block_dump",
1142 .data = &block_dump,
1143 .maxlen = sizeof(block_dump),
1145 .proc_handler = &proc_dointvec,
1146 .strategy = &sysctl_intvec,
1150 .ctl_name = VM_VFS_CACHE_PRESSURE,
1151 .procname = "vfs_cache_pressure",
1152 .data = &sysctl_vfs_cache_pressure,
1153 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1155 .proc_handler = &proc_dointvec,
1156 .strategy = &sysctl_intvec,
1159 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1161 .ctl_name = VM_LEGACY_VA_LAYOUT,
1162 .procname = "legacy_va_layout",
1163 .data = &sysctl_legacy_va_layout,
1164 .maxlen = sizeof(sysctl_legacy_va_layout),
1166 .proc_handler = &proc_dointvec,
1167 .strategy = &sysctl_intvec,
1173 .ctl_name = VM_ZONE_RECLAIM_MODE,
1174 .procname = "zone_reclaim_mode",
1175 .data = &zone_reclaim_mode,
1176 .maxlen = sizeof(zone_reclaim_mode),
1178 .proc_handler = &proc_dointvec,
1179 .strategy = &sysctl_intvec,
1183 .ctl_name = VM_MIN_UNMAPPED,
1184 .procname = "min_unmapped_ratio",
1185 .data = &sysctl_min_unmapped_ratio,
1186 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1188 .proc_handler = &sysctl_min_unmapped_ratio_sysctl_handler,
1189 .strategy = &sysctl_intvec,
1191 .extra2 = &one_hundred,
1194 .ctl_name = VM_MIN_SLAB,
1195 .procname = "min_slab_ratio",
1196 .data = &sysctl_min_slab_ratio,
1197 .maxlen = sizeof(sysctl_min_slab_ratio),
1199 .proc_handler = &sysctl_min_slab_ratio_sysctl_handler,
1200 .strategy = &sysctl_intvec,
1202 .extra2 = &one_hundred,
1207 .ctl_name = CTL_UNNUMBERED,
1208 .procname = "stat_interval",
1209 .data = &sysctl_stat_interval,
1210 .maxlen = sizeof(sysctl_stat_interval),
1212 .proc_handler = &proc_dointvec_jiffies,
1213 .strategy = &sysctl_jiffies,
1216 #ifdef CONFIG_SECURITY
1218 .ctl_name = CTL_UNNUMBERED,
1219 .procname = "mmap_min_addr",
1220 .data = &mmap_min_addr,
1221 .maxlen = sizeof(unsigned long),
1223 .proc_handler = &proc_doulongvec_minmax,
1228 .ctl_name = CTL_UNNUMBERED,
1229 .procname = "numa_zonelist_order",
1230 .data = &numa_zonelist_order,
1231 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1233 .proc_handler = &numa_zonelist_order_handler,
1234 .strategy = &sysctl_string,
1237 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1238 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1240 .ctl_name = VM_VDSO_ENABLED,
1241 .procname = "vdso_enabled",
1242 .data = &vdso_enabled,
1243 .maxlen = sizeof(vdso_enabled),
1245 .proc_handler = &proc_dointvec,
1246 .strategy = &sysctl_intvec,
1250 #ifdef CONFIG_HIGHMEM
1252 .ctl_name = CTL_UNNUMBERED,
1253 .procname = "highmem_is_dirtyable",
1254 .data = &vm_highmem_is_dirtyable,
1255 .maxlen = sizeof(vm_highmem_is_dirtyable),
1257 .proc_handler = &proc_dointvec_minmax,
1258 .strategy = &sysctl_intvec,
1264 * NOTE: do not add new entries to this table unless you have read
1265 * Documentation/sysctl/ctl_unnumbered.txt
1270 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1271 static struct ctl_table binfmt_misc_table[] = {
1276 static struct ctl_table fs_table[] = {
1278 .ctl_name = FS_NRINODE,
1279 .procname = "inode-nr",
1280 .data = &inodes_stat,
1281 .maxlen = 2*sizeof(int),
1283 .proc_handler = &proc_dointvec,
1286 .ctl_name = FS_STATINODE,
1287 .procname = "inode-state",
1288 .data = &inodes_stat,
1289 .maxlen = 7*sizeof(int),
1291 .proc_handler = &proc_dointvec,
1294 .procname = "file-nr",
1295 .data = &files_stat,
1296 .maxlen = 3*sizeof(int),
1298 .proc_handler = &proc_nr_files,
1301 .ctl_name = FS_MAXFILE,
1302 .procname = "file-max",
1303 .data = &files_stat.max_files,
1304 .maxlen = sizeof(int),
1306 .proc_handler = &proc_dointvec,
1309 .ctl_name = CTL_UNNUMBERED,
1310 .procname = "nr_open",
1311 .data = &sysctl_nr_open,
1312 .maxlen = sizeof(int),
1314 .proc_handler = &proc_dointvec_minmax,
1315 .extra1 = &sysctl_nr_open_min,
1316 .extra2 = &sysctl_nr_open_max,
1319 .ctl_name = FS_DENTRY,
1320 .procname = "dentry-state",
1321 .data = &dentry_stat,
1322 .maxlen = 6*sizeof(int),
1324 .proc_handler = &proc_dointvec,
1327 .ctl_name = FS_OVERFLOWUID,
1328 .procname = "overflowuid",
1329 .data = &fs_overflowuid,
1330 .maxlen = sizeof(int),
1332 .proc_handler = &proc_dointvec_minmax,
1333 .strategy = &sysctl_intvec,
1334 .extra1 = &minolduid,
1335 .extra2 = &maxolduid,
1338 .ctl_name = FS_OVERFLOWGID,
1339 .procname = "overflowgid",
1340 .data = &fs_overflowgid,
1341 .maxlen = sizeof(int),
1343 .proc_handler = &proc_dointvec_minmax,
1344 .strategy = &sysctl_intvec,
1345 .extra1 = &minolduid,
1346 .extra2 = &maxolduid,
1348 #ifdef CONFIG_FILE_LOCKING
1350 .ctl_name = FS_LEASES,
1351 .procname = "leases-enable",
1352 .data = &leases_enable,
1353 .maxlen = sizeof(int),
1355 .proc_handler = &proc_dointvec,
1358 #ifdef CONFIG_DNOTIFY
1360 .ctl_name = FS_DIR_NOTIFY,
1361 .procname = "dir-notify-enable",
1362 .data = &dir_notify_enable,
1363 .maxlen = sizeof(int),
1365 .proc_handler = &proc_dointvec,
1369 #ifdef CONFIG_FILE_LOCKING
1371 .ctl_name = FS_LEASE_TIME,
1372 .procname = "lease-break-time",
1373 .data = &lease_break_time,
1374 .maxlen = sizeof(int),
1376 .proc_handler = &proc_dointvec_minmax,
1377 .strategy = &sysctl_intvec,
1384 .procname = "aio-nr",
1386 .maxlen = sizeof(aio_nr),
1388 .proc_handler = &proc_doulongvec_minmax,
1391 .procname = "aio-max-nr",
1392 .data = &aio_max_nr,
1393 .maxlen = sizeof(aio_max_nr),
1395 .proc_handler = &proc_doulongvec_minmax,
1397 #endif /* CONFIG_AIO */
1398 #ifdef CONFIG_INOTIFY_USER
1400 .ctl_name = FS_INOTIFY,
1401 .procname = "inotify",
1403 .child = inotify_table,
1408 .procname = "epoll",
1410 .child = epoll_table,
1415 .ctl_name = KERN_SETUID_DUMPABLE,
1416 .procname = "suid_dumpable",
1417 .data = &suid_dumpable,
1418 .maxlen = sizeof(int),
1420 .proc_handler = &proc_dointvec,
1422 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1424 .ctl_name = CTL_UNNUMBERED,
1425 .procname = "binfmt_misc",
1427 .child = binfmt_misc_table,
1431 * NOTE: do not add new entries to this table unless you have read
1432 * Documentation/sysctl/ctl_unnumbered.txt
1437 static struct ctl_table debug_table[] = {
1438 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1440 .ctl_name = CTL_UNNUMBERED,
1441 .procname = "exception-trace",
1442 .data = &show_unhandled_signals,
1443 .maxlen = sizeof(int),
1445 .proc_handler = proc_dointvec
1451 static struct ctl_table dev_table[] = {
1455 static DEFINE_SPINLOCK(sysctl_lock);
1457 /* called under sysctl_lock */
1458 static int use_table(struct ctl_table_header *p)
1460 if (unlikely(p->unregistering))
1466 /* called under sysctl_lock */
1467 static void unuse_table(struct ctl_table_header *p)
1470 if (unlikely(p->unregistering))
1471 complete(p->unregistering);
1474 /* called under sysctl_lock, will reacquire if has to wait */
1475 static void start_unregistering(struct ctl_table_header *p)
1478 * if p->used is 0, nobody will ever touch that entry again;
1479 * we'll eliminate all paths to it before dropping sysctl_lock
1481 if (unlikely(p->used)) {
1482 struct completion wait;
1483 init_completion(&wait);
1484 p->unregistering = &wait;
1485 spin_unlock(&sysctl_lock);
1486 wait_for_completion(&wait);
1487 spin_lock(&sysctl_lock);
1489 /* anything non-NULL; we'll never dereference it */
1490 p->unregistering = ERR_PTR(-EINVAL);
1493 * do not remove from the list until nobody holds it; walking the
1494 * list in do_sysctl() relies on that.
1496 list_del_init(&p->ctl_entry);
1499 void sysctl_head_get(struct ctl_table_header *head)
1501 spin_lock(&sysctl_lock);
1503 spin_unlock(&sysctl_lock);
1506 void sysctl_head_put(struct ctl_table_header *head)
1508 spin_lock(&sysctl_lock);
1511 spin_unlock(&sysctl_lock);
1514 struct ctl_table_header *sysctl_head_grab(struct ctl_table_header *head)
1518 spin_lock(&sysctl_lock);
1519 if (!use_table(head))
1520 head = ERR_PTR(-ENOENT);
1521 spin_unlock(&sysctl_lock);
1525 void sysctl_head_finish(struct ctl_table_header *head)
1529 spin_lock(&sysctl_lock);
1531 spin_unlock(&sysctl_lock);
1534 static struct ctl_table_set *
1535 lookup_header_set(struct ctl_table_root *root, struct nsproxy *namespaces)
1537 struct ctl_table_set *set = &root->default_set;
1539 set = root->lookup(root, namespaces);
1543 static struct list_head *
1544 lookup_header_list(struct ctl_table_root *root, struct nsproxy *namespaces)
1546 struct ctl_table_set *set = lookup_header_set(root, namespaces);
1550 struct ctl_table_header *__sysctl_head_next(struct nsproxy *namespaces,
1551 struct ctl_table_header *prev)
1553 struct ctl_table_root *root;
1554 struct list_head *header_list;
1555 struct ctl_table_header *head;
1556 struct list_head *tmp;
1558 spin_lock(&sysctl_lock);
1561 tmp = &prev->ctl_entry;
1565 tmp = &root_table_header.ctl_entry;
1567 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1569 if (!use_table(head))
1571 spin_unlock(&sysctl_lock);
1576 header_list = lookup_header_list(root, namespaces);
1577 if (tmp != header_list)
1581 root = list_entry(root->root_list.next,
1582 struct ctl_table_root, root_list);
1583 if (root == &sysctl_table_root)
1585 header_list = lookup_header_list(root, namespaces);
1586 } while (list_empty(header_list));
1587 tmp = header_list->next;
1590 spin_unlock(&sysctl_lock);
1594 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1596 return __sysctl_head_next(current->nsproxy, prev);
1599 void register_sysctl_root(struct ctl_table_root *root)
1601 spin_lock(&sysctl_lock);
1602 list_add_tail(&root->root_list, &sysctl_table_root.root_list);
1603 spin_unlock(&sysctl_lock);
1606 #ifdef CONFIG_SYSCTL_SYSCALL
1607 /* Perform the actual read/write of a sysctl table entry. */
1608 static int do_sysctl_strategy(struct ctl_table_root *root,
1609 struct ctl_table *table,
1610 void __user *oldval, size_t __user *oldlenp,
1611 void __user *newval, size_t newlen)
1619 if (sysctl_perm(root, table, op))
1622 if (table->strategy) {
1623 rc = table->strategy(table, oldval, oldlenp, newval, newlen);
1630 /* If there is no strategy routine, or if the strategy returns
1631 * zero, proceed with automatic r/w */
1632 if (table->data && table->maxlen) {
1633 rc = sysctl_data(table, oldval, oldlenp, newval, newlen);
1640 static int parse_table(int __user *name, int nlen,
1641 void __user *oldval, size_t __user *oldlenp,
1642 void __user *newval, size_t newlen,
1643 struct ctl_table_root *root,
1644 struct ctl_table *table)
1650 if (get_user(n, name))
1652 for ( ; table->ctl_name || table->procname; table++) {
1653 if (!table->ctl_name)
1655 if (n == table->ctl_name) {
1658 if (sysctl_perm(root, table, MAY_EXEC))
1662 table = table->child;
1665 error = do_sysctl_strategy(root, table,
1674 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1675 void __user *newval, size_t newlen)
1677 struct ctl_table_header *head;
1678 int error = -ENOTDIR;
1680 if (nlen <= 0 || nlen >= CTL_MAXNAME)
1684 if (!oldlenp || get_user(old_len, oldlenp))
1688 for (head = sysctl_head_next(NULL); head;
1689 head = sysctl_head_next(head)) {
1690 error = parse_table(name, nlen, oldval, oldlenp,
1692 head->root, head->ctl_table);
1693 if (error != -ENOTDIR) {
1694 sysctl_head_finish(head);
1701 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
1703 struct __sysctl_args tmp;
1706 if (copy_from_user(&tmp, args, sizeof(tmp)))
1709 error = deprecated_sysctl_warning(&tmp);
1714 error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1715 tmp.newval, tmp.newlen);
1720 #endif /* CONFIG_SYSCTL_SYSCALL */
1723 * sysctl_perm does NOT grant the superuser all rights automatically, because
1724 * some sysctl variables are readonly even to root.
1727 static int test_perm(int mode, int op)
1729 if (!current_euid())
1731 else if (in_egroup_p(0))
1733 if ((op & ~mode & (MAY_READ|MAY_WRITE|MAY_EXEC)) == 0)
1738 int sysctl_perm(struct ctl_table_root *root, struct ctl_table *table, int op)
1743 error = security_sysctl(table, op & (MAY_READ | MAY_WRITE | MAY_EXEC));
1747 if (root->permissions)
1748 mode = root->permissions(root, current->nsproxy, table);
1752 return test_perm(mode, op);
1755 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1757 for (; table->ctl_name || table->procname; table++) {
1758 table->parent = parent;
1760 sysctl_set_parent(table, table->child);
1764 static __init int sysctl_init(void)
1766 sysctl_set_parent(NULL, root_table);
1767 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1770 err = sysctl_check_table(current->nsproxy, root_table);
1776 core_initcall(sysctl_init);
1778 static struct ctl_table *is_branch_in(struct ctl_table *branch,
1779 struct ctl_table *table)
1781 struct ctl_table *p;
1782 const char *s = branch->procname;
1784 /* branch should have named subdirectory as its first element */
1785 if (!s || !branch->child)
1788 /* ... and nothing else */
1789 if (branch[1].procname || branch[1].ctl_name)
1792 /* table should contain subdirectory with the same name */
1793 for (p = table; p->procname || p->ctl_name; p++) {
1796 if (p->procname && strcmp(p->procname, s) == 0)
1802 /* see if attaching q to p would be an improvement */
1803 static void try_attach(struct ctl_table_header *p, struct ctl_table_header *q)
1805 struct ctl_table *to = p->ctl_table, *by = q->ctl_table;
1806 struct ctl_table *next;
1808 int not_in_parent = !p->attached_by;
1810 while ((next = is_branch_in(by, to)) != NULL) {
1811 if (by == q->attached_by)
1813 if (to == p->attached_by)
1819 if (is_better && not_in_parent) {
1820 q->attached_by = by;
1821 q->attached_to = to;
1827 * __register_sysctl_paths - register a sysctl hierarchy
1828 * @root: List of sysctl headers to register on
1829 * @namespaces: Data to compute which lists of sysctl entries are visible
1830 * @path: The path to the directory the sysctl table is in.
1831 * @table: the top-level table structure
1833 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1834 * array. A completely 0 filled entry terminates the table.
1836 * The members of the &struct ctl_table structure are used as follows:
1838 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1839 * must be unique within that level of sysctl
1841 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1842 * enter a sysctl file
1844 * data - a pointer to data for use by proc_handler
1846 * maxlen - the maximum size in bytes of the data
1848 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1850 * child - a pointer to the child sysctl table if this entry is a directory, or
1853 * proc_handler - the text handler routine (described below)
1855 * strategy - the strategy routine (described below)
1857 * de - for internal use by the sysctl routines
1859 * extra1, extra2 - extra pointers usable by the proc handler routines
1861 * Leaf nodes in the sysctl tree will be represented by a single file
1862 * under /proc; non-leaf nodes will be represented by directories.
1864 * sysctl(2) can automatically manage read and write requests through
1865 * the sysctl table. The data and maxlen fields of the ctl_table
1866 * struct enable minimal validation of the values being written to be
1867 * performed, and the mode field allows minimal authentication.
1869 * More sophisticated management can be enabled by the provision of a
1870 * strategy routine with the table entry. This will be called before
1871 * any automatic read or write of the data is performed.
1873 * The strategy routine may return
1875 * < 0 - Error occurred (error is passed to user process)
1877 * 0 - OK - proceed with automatic read or write.
1879 * > 0 - OK - read or write has been done by the strategy routine, so
1880 * return immediately.
1882 * There must be a proc_handler routine for any terminal nodes
1883 * mirrored under /proc/sys (non-terminals are handled by a built-in
1884 * directory handler). Several default handlers are available to
1885 * cover common cases -
1887 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1888 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1889 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1891 * It is the handler's job to read the input buffer from user memory
1892 * and process it. The handler should return 0 on success.
1894 * This routine returns %NULL on a failure to register, and a pointer
1895 * to the table header on success.
1897 struct ctl_table_header *__register_sysctl_paths(
1898 struct ctl_table_root *root,
1899 struct nsproxy *namespaces,
1900 const struct ctl_path *path, struct ctl_table *table)
1902 struct ctl_table_header *header;
1903 struct ctl_table *new, **prevp;
1904 unsigned int n, npath;
1905 struct ctl_table_set *set;
1907 /* Count the path components */
1908 for (npath = 0; path[npath].ctl_name || path[npath].procname; ++npath)
1912 * For each path component, allocate a 2-element ctl_table array.
1913 * The first array element will be filled with the sysctl entry
1914 * for this, the second will be the sentinel (ctl_name == 0).
1916 * We allocate everything in one go so that we don't have to
1917 * worry about freeing additional memory in unregister_sysctl_table.
1919 header = kzalloc(sizeof(struct ctl_table_header) +
1920 (2 * npath * sizeof(struct ctl_table)), GFP_KERNEL);
1924 new = (struct ctl_table *) (header + 1);
1926 /* Now connect the dots */
1927 prevp = &header->ctl_table;
1928 for (n = 0; n < npath; ++n, ++path) {
1929 /* Copy the procname */
1930 new->procname = path->procname;
1931 new->ctl_name = path->ctl_name;
1935 prevp = &new->child;
1940 header->ctl_table_arg = table;
1942 INIT_LIST_HEAD(&header->ctl_entry);
1944 header->unregistering = NULL;
1945 header->root = root;
1946 sysctl_set_parent(NULL, header->ctl_table);
1948 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1949 if (sysctl_check_table(namespaces, header->ctl_table)) {
1954 spin_lock(&sysctl_lock);
1955 header->set = lookup_header_set(root, namespaces);
1956 header->attached_by = header->ctl_table;
1957 header->attached_to = root_table;
1958 header->parent = &root_table_header;
1959 for (set = header->set; set; set = set->parent) {
1960 struct ctl_table_header *p;
1961 list_for_each_entry(p, &set->list, ctl_entry) {
1962 if (p->unregistering)
1964 try_attach(p, header);
1967 header->parent->count++;
1968 list_add_tail(&header->ctl_entry, &header->set->list);
1969 spin_unlock(&sysctl_lock);
1975 * register_sysctl_table_path - register a sysctl table hierarchy
1976 * @path: The path to the directory the sysctl table is in.
1977 * @table: the top-level table structure
1979 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1980 * array. A completely 0 filled entry terminates the table.
1982 * See __register_sysctl_paths for more details.
1984 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
1985 struct ctl_table *table)
1987 return __register_sysctl_paths(&sysctl_table_root, current->nsproxy,
1992 * register_sysctl_table - register a sysctl table hierarchy
1993 * @table: the top-level table structure
1995 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1996 * array. A completely 0 filled entry terminates the table.
1998 * See register_sysctl_paths for more details.
2000 struct ctl_table_header *register_sysctl_table(struct ctl_table *table)
2002 static const struct ctl_path null_path[] = { {} };
2004 return register_sysctl_paths(null_path, table);
2008 * unregister_sysctl_table - unregister a sysctl table hierarchy
2009 * @header: the header returned from register_sysctl_table
2011 * Unregisters the sysctl table and all children. proc entries may not
2012 * actually be removed until they are no longer used by anyone.
2014 void unregister_sysctl_table(struct ctl_table_header * header)
2021 spin_lock(&sysctl_lock);
2022 start_unregistering(header);
2023 if (!--header->parent->count) {
2025 kfree(header->parent);
2027 if (!--header->count)
2029 spin_unlock(&sysctl_lock);
2032 int sysctl_is_seen(struct ctl_table_header *p)
2034 struct ctl_table_set *set = p->set;
2036 spin_lock(&sysctl_lock);
2037 if (p->unregistering)
2039 else if (!set->is_seen)
2042 res = set->is_seen(set);
2043 spin_unlock(&sysctl_lock);
2047 void setup_sysctl_set(struct ctl_table_set *p,
2048 struct ctl_table_set *parent,
2049 int (*is_seen)(struct ctl_table_set *))
2051 INIT_LIST_HEAD(&p->list);
2052 p->parent = parent ? parent : &sysctl_table_root.default_set;
2053 p->is_seen = is_seen;
2056 #else /* !CONFIG_SYSCTL */
2057 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
2062 struct ctl_table_header *register_sysctl_paths(const struct ctl_path *path,
2063 struct ctl_table *table)
2068 void unregister_sysctl_table(struct ctl_table_header * table)
2072 void setup_sysctl_set(struct ctl_table_set *p,
2073 struct ctl_table_set *parent,
2074 int (*is_seen)(struct ctl_table_set *))
2078 void sysctl_head_put(struct ctl_table_header *head)
2082 #endif /* CONFIG_SYSCTL */
2088 #ifdef CONFIG_PROC_SYSCTL
2090 static int _proc_do_string(void* data, int maxlen, int write,
2091 struct file *filp, void __user *buffer,
2092 size_t *lenp, loff_t *ppos)
2098 if (!data || !maxlen || !*lenp) {
2106 while (len < *lenp) {
2107 if (get_user(c, p++))
2109 if (c == 0 || c == '\n')
2115 if(copy_from_user(data, buffer, len))
2117 ((char *) data)[len] = 0;
2135 if(copy_to_user(buffer, data, len))
2138 if(put_user('\n', ((char __user *) buffer) + len))
2149 * proc_dostring - read a string sysctl
2150 * @table: the sysctl table
2151 * @write: %TRUE if this is a write to the sysctl file
2152 * @filp: the file structure
2153 * @buffer: the user buffer
2154 * @lenp: the size of the user buffer
2155 * @ppos: file position
2157 * Reads/writes a string from/to the user buffer. If the kernel
2158 * buffer provided is not large enough to hold the string, the
2159 * string is truncated. The copied string is %NULL-terminated.
2160 * If the string is being read by the user process, it is copied
2161 * and a newline '\n' is added. It is truncated if the buffer is
2164 * Returns 0 on success.
2166 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2167 void __user *buffer, size_t *lenp, loff_t *ppos)
2169 return _proc_do_string(table->data, table->maxlen, write, filp,
2170 buffer, lenp, ppos);
2174 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
2176 int write, void *data)
2179 *valp = *negp ? -*lvalp : *lvalp;
2184 *lvalp = (unsigned long)-val;
2187 *lvalp = (unsigned long)val;
2193 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2194 int write, struct file *filp, void __user *buffer,
2195 size_t *lenp, loff_t *ppos,
2196 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2197 int write, void *data),
2200 #define TMPBUFLEN 21
2201 int *i, vleft, first=1, neg, val;
2205 char buf[TMPBUFLEN], *p;
2206 char __user *s = buffer;
2208 if (!tbl_data || !table->maxlen || !*lenp ||
2209 (*ppos && !write)) {
2214 i = (int *) tbl_data;
2215 vleft = table->maxlen / sizeof(*i);
2219 conv = do_proc_dointvec_conv;
2221 for (; left && vleft--; i++, first=0) {
2236 if (len > sizeof(buf) - 1)
2237 len = sizeof(buf) - 1;
2238 if (copy_from_user(buf, s, len))
2242 if (*p == '-' && left > 1) {
2246 if (*p < '0' || *p > '9')
2249 lval = simple_strtoul(p, &p, 0);
2252 if ((len < left) && *p && !isspace(*p))
2259 if (conv(&neg, &lval, i, 1, data))
2266 if (conv(&neg, &lval, i, 0, data))
2269 sprintf(p, "%s%lu", neg ? "-" : "", lval);
2273 if(copy_to_user(s, buf, len))
2280 if (!write && !first && left) {
2281 if(put_user('\n', s))
2288 if (get_user(c, s++))
2303 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2304 void __user *buffer, size_t *lenp, loff_t *ppos,
2305 int (*conv)(int *negp, unsigned long *lvalp, int *valp,
2306 int write, void *data),
2309 return __do_proc_dointvec(table->data, table, write, filp,
2310 buffer, lenp, ppos, conv, data);
2314 * proc_dointvec - read a vector of integers
2315 * @table: the sysctl table
2316 * @write: %TRUE if this is a write to the sysctl file
2317 * @filp: the file structure
2318 * @buffer: the user buffer
2319 * @lenp: the size of the user buffer
2320 * @ppos: file position
2322 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2323 * values from/to the user buffer, treated as an ASCII string.
2325 * Returns 0 on success.
2327 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2328 void __user *buffer, size_t *lenp, loff_t *ppos)
2330 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2335 * Taint values can only be increased
2336 * This means we can safely use a temporary.
2338 static int proc_taint(struct ctl_table *table, int write, struct file *filp,
2339 void __user *buffer, size_t *lenp, loff_t *ppos)
2342 unsigned long tmptaint = get_taint();
2345 if (write && !capable(CAP_SYS_ADMIN))
2350 err = proc_doulongvec_minmax(&t, write, filp, buffer, lenp, ppos);
2356 * Poor man's atomic or. Not worth adding a primitive
2357 * to everyone's atomic.h for this
2360 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2361 if ((tmptaint >> i) & 1)
2369 struct do_proc_dointvec_minmax_conv_param {
2374 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp,
2376 int write, void *data)
2378 struct do_proc_dointvec_minmax_conv_param *param = data;
2380 int val = *negp ? -*lvalp : *lvalp;
2381 if ((param->min && *param->min > val) ||
2382 (param->max && *param->max < val))
2389 *lvalp = (unsigned long)-val;
2392 *lvalp = (unsigned long)val;
2399 * proc_dointvec_minmax - read a vector of integers with min/max values
2400 * @table: the sysctl table
2401 * @write: %TRUE if this is a write to the sysctl file
2402 * @filp: the file structure
2403 * @buffer: the user buffer
2404 * @lenp: the size of the user buffer
2405 * @ppos: file position
2407 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2408 * values from/to the user buffer, treated as an ASCII string.
2410 * This routine will ensure the values are within the range specified by
2411 * table->extra1 (min) and table->extra2 (max).
2413 * Returns 0 on success.
2415 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2416 void __user *buffer, size_t *lenp, loff_t *ppos)
2418 struct do_proc_dointvec_minmax_conv_param param = {
2419 .min = (int *) table->extra1,
2420 .max = (int *) table->extra2,
2422 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2423 do_proc_dointvec_minmax_conv, ¶m);
2426 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2428 void __user *buffer,
2429 size_t *lenp, loff_t *ppos,
2430 unsigned long convmul,
2431 unsigned long convdiv)
2433 #define TMPBUFLEN 21
2434 unsigned long *i, *min, *max, val;
2435 int vleft, first=1, neg;
2437 char buf[TMPBUFLEN], *p;
2438 char __user *s = buffer;
2440 if (!data || !table->maxlen || !*lenp ||
2441 (*ppos && !write)) {
2446 i = (unsigned long *) data;
2447 min = (unsigned long *) table->extra1;
2448 max = (unsigned long *) table->extra2;
2449 vleft = table->maxlen / sizeof(unsigned long);
2452 for (; left && vleft--; i++, min++, max++, first=0) {
2467 if (len > TMPBUFLEN-1)
2469 if (copy_from_user(buf, s, len))
2473 if (*p == '-' && left > 1) {
2477 if (*p < '0' || *p > '9')
2479 val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2481 if ((len < left) && *p && !isspace(*p))
2490 if ((min && val < *min) || (max && val > *max))
2497 sprintf(p, "%lu", convdiv * (*i) / convmul);
2501 if(copy_to_user(s, buf, len))
2508 if (!write && !first && left) {
2509 if(put_user('\n', s))
2516 if (get_user(c, s++))
2531 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2533 void __user *buffer,
2534 size_t *lenp, loff_t *ppos,
2535 unsigned long convmul,
2536 unsigned long convdiv)
2538 return __do_proc_doulongvec_minmax(table->data, table, write,
2539 filp, buffer, lenp, ppos, convmul, convdiv);
2543 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2544 * @table: the sysctl table
2545 * @write: %TRUE if this is a write to the sysctl file
2546 * @filp: the file structure
2547 * @buffer: the user buffer
2548 * @lenp: the size of the user buffer
2549 * @ppos: file position
2551 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2552 * values from/to the user buffer, treated as an ASCII string.
2554 * This routine will ensure the values are within the range specified by
2555 * table->extra1 (min) and table->extra2 (max).
2557 * Returns 0 on success.
2559 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2560 void __user *buffer, size_t *lenp, loff_t *ppos)
2562 return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2566 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2567 * @table: the sysctl table
2568 * @write: %TRUE if this is a write to the sysctl file
2569 * @filp: the file structure
2570 * @buffer: the user buffer
2571 * @lenp: the size of the user buffer
2572 * @ppos: file position
2574 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2575 * values from/to the user buffer, treated as an ASCII string. The values
2576 * are treated as milliseconds, and converted to jiffies when they are stored.
2578 * This routine will ensure the values are within the range specified by
2579 * table->extra1 (min) and table->extra2 (max).
2581 * Returns 0 on success.
2583 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2585 void __user *buffer,
2586 size_t *lenp, loff_t *ppos)
2588 return do_proc_doulongvec_minmax(table, write, filp, buffer,
2589 lenp, ppos, HZ, 1000l);
2593 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2595 int write, void *data)
2598 if (*lvalp > LONG_MAX / HZ)
2600 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2606 lval = (unsigned long)-val;
2609 lval = (unsigned long)val;
2616 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2618 int write, void *data)
2621 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2623 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2629 lval = (unsigned long)-val;
2632 lval = (unsigned long)val;
2634 *lvalp = jiffies_to_clock_t(lval);
2639 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2641 int write, void *data)
2644 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2650 lval = (unsigned long)-val;
2653 lval = (unsigned long)val;
2655 *lvalp = jiffies_to_msecs(lval);
2661 * proc_dointvec_jiffies - read a vector of integers as seconds
2662 * @table: the sysctl table
2663 * @write: %TRUE if this is a write to the sysctl file
2664 * @filp: the file structure
2665 * @buffer: the user buffer
2666 * @lenp: the size of the user buffer
2667 * @ppos: file position
2669 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2670 * values from/to the user buffer, treated as an ASCII string.
2671 * The values read are assumed to be in seconds, and are converted into
2674 * Returns 0 on success.
2676 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2677 void __user *buffer, size_t *lenp, loff_t *ppos)
2679 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2680 do_proc_dointvec_jiffies_conv,NULL);
2684 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2685 * @table: the sysctl table
2686 * @write: %TRUE if this is a write to the sysctl file
2687 * @filp: the file structure
2688 * @buffer: the user buffer
2689 * @lenp: the size of the user buffer
2690 * @ppos: pointer to the file position
2692 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2693 * values from/to the user buffer, treated as an ASCII string.
2694 * The values read are assumed to be in 1/USER_HZ seconds, and
2695 * are converted into jiffies.
2697 * Returns 0 on success.
2699 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2700 void __user *buffer, size_t *lenp, loff_t *ppos)
2702 return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2703 do_proc_dointvec_userhz_jiffies_conv,NULL);
2707 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2708 * @table: the sysctl table
2709 * @write: %TRUE if this is a write to the sysctl file
2710 * @filp: the file structure
2711 * @buffer: the user buffer
2712 * @lenp: the size of the user buffer
2713 * @ppos: file position
2714 * @ppos: the current position in the file
2716 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2717 * values from/to the user buffer, treated as an ASCII string.
2718 * The values read are assumed to be in 1/1000 seconds, and
2719 * are converted into jiffies.
2721 * Returns 0 on success.
2723 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2724 void __user *buffer, size_t *lenp, loff_t *ppos)
2726 return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2727 do_proc_dointvec_ms_jiffies_conv, NULL);
2730 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2731 void __user *buffer, size_t *lenp, loff_t *ppos)
2733 struct pid *new_pid;
2737 tmp = pid_vnr(cad_pid);
2739 r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2740 lenp, ppos, NULL, NULL);
2744 new_pid = find_get_pid(tmp);
2748 put_pid(xchg(&cad_pid, new_pid));
2752 #else /* CONFIG_PROC_FS */
2754 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2755 void __user *buffer, size_t *lenp, loff_t *ppos)
2760 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2761 void __user *buffer, size_t *lenp, loff_t *ppos)
2766 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2767 void __user *buffer, size_t *lenp, loff_t *ppos)
2772 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2773 void __user *buffer, size_t *lenp, loff_t *ppos)
2778 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2779 void __user *buffer, size_t *lenp, loff_t *ppos)
2784 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2785 void __user *buffer, size_t *lenp, loff_t *ppos)
2790 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2791 void __user *buffer, size_t *lenp, loff_t *ppos)
2796 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2798 void __user *buffer,
2799 size_t *lenp, loff_t *ppos)
2805 #endif /* CONFIG_PROC_FS */
2808 #ifdef CONFIG_SYSCTL_SYSCALL
2810 * General sysctl support routines
2813 /* The generic sysctl data routine (used if no strategy routine supplied) */
2814 int sysctl_data(struct ctl_table *table,
2815 void __user *oldval, size_t __user *oldlenp,
2816 void __user *newval, size_t newlen)
2820 /* Get out of I don't have a variable */
2821 if (!table->data || !table->maxlen)
2824 if (oldval && oldlenp) {
2825 if (get_user(len, oldlenp))
2828 if (len > table->maxlen)
2829 len = table->maxlen;
2830 if (copy_to_user(oldval, table->data, len))
2832 if (put_user(len, oldlenp))
2837 if (newval && newlen) {
2838 if (newlen > table->maxlen)
2839 newlen = table->maxlen;
2841 if (copy_from_user(table->data, newval, newlen))
2847 /* The generic string strategy routine: */
2848 int sysctl_string(struct ctl_table *table,
2849 void __user *oldval, size_t __user *oldlenp,
2850 void __user *newval, size_t newlen)
2852 if (!table->data || !table->maxlen)
2855 if (oldval && oldlenp) {
2857 if (get_user(bufsize, oldlenp))
2860 size_t len = strlen(table->data), copied;
2862 /* This shouldn't trigger for a well-formed sysctl */
2863 if (len > table->maxlen)
2864 len = table->maxlen;
2866 /* Copy up to a max of bufsize-1 bytes of the string */
2867 copied = (len >= bufsize) ? bufsize - 1 : len;
2869 if (copy_to_user(oldval, table->data, copied) ||
2870 put_user(0, (char __user *)(oldval + copied)))
2872 if (put_user(len, oldlenp))
2876 if (newval && newlen) {
2877 size_t len = newlen;
2878 if (len > table->maxlen)
2879 len = table->maxlen;
2880 if(copy_from_user(table->data, newval, len))
2882 if (len == table->maxlen)
2884 ((char *) table->data)[len] = 0;
2890 * This function makes sure that all of the integers in the vector
2891 * are between the minimum and maximum values given in the arrays
2892 * table->extra1 and table->extra2, respectively.
2894 int sysctl_intvec(struct ctl_table *table,
2895 void __user *oldval, size_t __user *oldlenp,
2896 void __user *newval, size_t newlen)
2899 if (newval && newlen) {
2900 int __user *vec = (int __user *) newval;
2901 int *min = (int *) table->extra1;
2902 int *max = (int *) table->extra2;
2906 if (newlen % sizeof(int) != 0)
2909 if (!table->extra1 && !table->extra2)
2912 if (newlen > table->maxlen)
2913 newlen = table->maxlen;
2914 length = newlen / sizeof(int);
2916 for (i = 0; i < length; i++) {
2918 if (get_user(value, vec + i))
2920 if (min && value < min[i])
2922 if (max && value > max[i])
2929 /* Strategy function to convert jiffies to seconds */
2930 int sysctl_jiffies(struct ctl_table *table,
2931 void __user *oldval, size_t __user *oldlenp,
2932 void __user *newval, size_t newlen)
2934 if (oldval && oldlenp) {
2937 if (get_user(olen, oldlenp))
2942 if (olen < sizeof(int))
2945 val = *(int *)(table->data) / HZ;
2946 if (put_user(val, (int __user *)oldval))
2948 if (put_user(sizeof(int), oldlenp))
2952 if (newval && newlen) {
2954 if (newlen != sizeof(int))
2956 if (get_user(new, (int __user *)newval))
2958 *(int *)(table->data) = new*HZ;
2963 /* Strategy function to convert jiffies to seconds */
2964 int sysctl_ms_jiffies(struct ctl_table *table,
2965 void __user *oldval, size_t __user *oldlenp,
2966 void __user *newval, size_t newlen)
2968 if (oldval && oldlenp) {
2971 if (get_user(olen, oldlenp))
2976 if (olen < sizeof(int))
2979 val = jiffies_to_msecs(*(int *)(table->data));
2980 if (put_user(val, (int __user *)oldval))
2982 if (put_user(sizeof(int), oldlenp))
2986 if (newval && newlen) {
2988 if (newlen != sizeof(int))
2990 if (get_user(new, (int __user *)newval))
2992 *(int *)(table->data) = msecs_to_jiffies(new);
2999 #else /* CONFIG_SYSCTL_SYSCALL */
3002 SYSCALL_DEFINE1(sysctl, struct __sysctl_args __user *, args)
3004 struct __sysctl_args tmp;
3007 if (copy_from_user(&tmp, args, sizeof(tmp)))
3010 error = deprecated_sysctl_warning(&tmp);
3012 /* If no error reading the parameters then just -ENOSYS ... */
3019 int sysctl_data(struct ctl_table *table,
3020 void __user *oldval, size_t __user *oldlenp,
3021 void __user *newval, size_t newlen)
3026 int sysctl_string(struct ctl_table *table,
3027 void __user *oldval, size_t __user *oldlenp,
3028 void __user *newval, size_t newlen)
3033 int sysctl_intvec(struct ctl_table *table,
3034 void __user *oldval, size_t __user *oldlenp,
3035 void __user *newval, size_t newlen)
3040 int sysctl_jiffies(struct ctl_table *table,
3041 void __user *oldval, size_t __user *oldlenp,
3042 void __user *newval, size_t newlen)
3047 int sysctl_ms_jiffies(struct ctl_table *table,
3048 void __user *oldval, size_t __user *oldlenp,
3049 void __user *newval, size_t newlen)
3054 #endif /* CONFIG_SYSCTL_SYSCALL */
3056 static int deprecated_sysctl_warning(struct __sysctl_args *args)
3058 static int msg_count;
3059 int name[CTL_MAXNAME];
3062 /* Check args->nlen. */
3063 if (args->nlen < 0 || args->nlen > CTL_MAXNAME)
3066 /* Read in the sysctl name for better debug message logging */
3067 for (i = 0; i < args->nlen; i++)
3068 if (get_user(name[i], args->name + i))
3071 /* Ignore accesses to kernel.version */
3072 if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
3075 if (msg_count < 5) {
3078 "warning: process `%s' used the deprecated sysctl "
3079 "system call with ", current->comm);
3080 for (i = 0; i < args->nlen; i++)
3081 printk("%d.", name[i]);
3088 * No sense putting this after each symbol definition, twice,
3089 * exception granted :-)
3091 EXPORT_SYMBOL(proc_dointvec);
3092 EXPORT_SYMBOL(proc_dointvec_jiffies);
3093 EXPORT_SYMBOL(proc_dointvec_minmax);
3094 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3095 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3096 EXPORT_SYMBOL(proc_dostring);
3097 EXPORT_SYMBOL(proc_doulongvec_minmax);
3098 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3099 EXPORT_SYMBOL(register_sysctl_table);
3100 EXPORT_SYMBOL(register_sysctl_paths);
3101 EXPORT_SYMBOL(sysctl_intvec);
3102 EXPORT_SYMBOL(sysctl_jiffies);
3103 EXPORT_SYMBOL(sysctl_ms_jiffies);
3104 EXPORT_SYMBOL(sysctl_string);
3105 EXPORT_SYMBOL(sysctl_data);
3106 EXPORT_SYMBOL(unregister_sysctl_table);