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/security.h>
41 #include <linux/initrd.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/nfs_fs.h>
47 #include <linux/acpi.h>
48 #include <linux/reboot.h>
50 #include <asm/uaccess.h>
51 #include <asm/processor.h>
55 #include <asm/stacktrace.h>
58 static int deprecated_sysctl_warning(struct __sysctl_args
*args
);
60 #if defined(CONFIG_SYSCTL)
62 /* External variables not in a header file. */
64 extern int print_fatal_signals
;
65 extern int sysctl_overcommit_memory
;
66 extern int sysctl_overcommit_ratio
;
67 extern int sysctl_panic_on_oom
;
68 extern int sysctl_oom_kill_allocating_task
;
69 extern int max_threads
;
70 extern int core_uses_pid
;
71 extern int suid_dumpable
;
72 extern char core_pattern
[];
74 extern int min_free_kbytes
;
75 extern int printk_ratelimit_jiffies
;
76 extern int printk_ratelimit_burst
;
77 extern int pid_max_min
, pid_max_max
;
78 extern int sysctl_drop_caches
;
79 extern int percpu_pagelist_fraction
;
80 extern int compat_log
;
81 extern int maps_protect
;
82 extern int sysctl_stat_interval
;
83 extern int audit_argv_kb
;
85 /* Constants used for minimum and maximum */
86 #ifdef CONFIG_DETECT_SOFTLOCKUP
88 static int sixty
= 60;
96 static int one_hundred
= 100;
98 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
99 static int maxolduid
= 65535;
100 static int minolduid
;
101 static int min_percpu_pagelist_fract
= 8;
103 static int ngroups_max
= NGROUPS_MAX
;
106 extern char modprobe_path
[];
108 #ifdef CONFIG_CHR_DEV_SG
109 extern int sg_big_buff
;
113 extern char reboot_command
[];
114 extern int stop_a_enabled
;
115 extern int scons_pwroff
;
119 extern int pwrsw_enabled
;
120 extern int unaligned_enabled
;
124 #ifdef CONFIG_MATHEMU
125 extern int sysctl_ieee_emulation_warnings
;
127 extern int sysctl_userprocess_debug
;
128 extern int spin_retry
;
131 extern int sysctl_hz_timer
;
133 #ifdef CONFIG_BSD_PROCESS_ACCT
134 extern int acct_parm
[];
138 extern int no_unaligned_warning
;
141 #ifdef CONFIG_RT_MUTEXES
142 extern int max_lock_depth
;
145 #ifdef CONFIG_SYSCTL_SYSCALL
146 static int parse_table(int __user
*, int, void __user
*, size_t __user
*,
147 void __user
*, size_t, struct ctl_table
*);
151 #ifdef CONFIG_PROC_SYSCTL
152 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
153 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
154 static int proc_dointvec_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
155 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
158 static struct ctl_table root_table
[];
159 static struct ctl_table_header root_table_header
=
160 { root_table
, LIST_HEAD_INIT(root_table_header
.ctl_entry
) };
162 static struct ctl_table kern_table
[];
163 static struct ctl_table vm_table
[];
164 static struct ctl_table fs_table
[];
165 static struct ctl_table debug_table
[];
166 static struct ctl_table dev_table
[];
167 extern struct ctl_table random_table
[];
168 #ifdef CONFIG_INOTIFY_USER
169 extern struct ctl_table inotify_table
[];
172 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
173 int sysctl_legacy_va_layout
;
176 extern int prove_locking
;
177 extern int lock_stat
;
179 /* The default sysctl tables: */
181 static struct ctl_table root_table
[] = {
183 .ctl_name
= CTL_KERN
,
184 .procname
= "kernel",
209 .ctl_name
= CTL_DEBUG
,
212 .child
= debug_table
,
221 * NOTE: do not add new entries to this table unless you have read
222 * Documentation/sysctl/ctl_unnumbered.txt
227 #ifdef CONFIG_SCHED_DEBUG
228 static unsigned long min_sched_granularity_ns
= 100000; /* 100 usecs */
229 static unsigned long max_sched_granularity_ns
= 1000000000; /* 1 second */
230 static unsigned long min_wakeup_granularity_ns
; /* 0 usecs */
231 static unsigned long max_wakeup_granularity_ns
= 1000000000; /* 1 second */
234 static struct ctl_table kern_table
[] = {
235 #ifdef CONFIG_SCHED_DEBUG
237 .ctl_name
= CTL_UNNUMBERED
,
238 .procname
= "sched_nr_latency",
239 .data
= &sysctl_sched_nr_latency
,
240 .maxlen
= sizeof(unsigned int),
242 .proc_handler
= &proc_dointvec
,
245 .ctl_name
= CTL_UNNUMBERED
,
246 .procname
= "sched_latency_ns",
247 .data
= &sysctl_sched_latency
,
248 .maxlen
= sizeof(unsigned int),
250 .proc_handler
= &proc_dointvec_minmax
,
251 .strategy
= &sysctl_intvec
,
252 .extra1
= &min_sched_granularity_ns
,
253 .extra2
= &max_sched_granularity_ns
,
256 .ctl_name
= CTL_UNNUMBERED
,
257 .procname
= "sched_wakeup_granularity_ns",
258 .data
= &sysctl_sched_wakeup_granularity
,
259 .maxlen
= sizeof(unsigned int),
261 .proc_handler
= &proc_dointvec_minmax
,
262 .strategy
= &sysctl_intvec
,
263 .extra1
= &min_wakeup_granularity_ns
,
264 .extra2
= &max_wakeup_granularity_ns
,
267 .ctl_name
= CTL_UNNUMBERED
,
268 .procname
= "sched_batch_wakeup_granularity_ns",
269 .data
= &sysctl_sched_batch_wakeup_granularity
,
270 .maxlen
= sizeof(unsigned int),
272 .proc_handler
= &proc_dointvec_minmax
,
273 .strategy
= &sysctl_intvec
,
274 .extra1
= &min_wakeup_granularity_ns
,
275 .extra2
= &max_wakeup_granularity_ns
,
278 .ctl_name
= CTL_UNNUMBERED
,
279 .procname
= "sched_child_runs_first",
280 .data
= &sysctl_sched_child_runs_first
,
281 .maxlen
= sizeof(unsigned int),
283 .proc_handler
= &proc_dointvec
,
286 .ctl_name
= CTL_UNNUMBERED
,
287 .procname
= "sched_features",
288 .data
= &sysctl_sched_features
,
289 .maxlen
= sizeof(unsigned int),
291 .proc_handler
= &proc_dointvec
,
294 .ctl_name
= CTL_UNNUMBERED
,
295 .procname
= "sched_migration_cost",
296 .data
= &sysctl_sched_migration_cost
,
297 .maxlen
= sizeof(unsigned int),
299 .proc_handler
= &proc_dointvec
,
303 .ctl_name
= CTL_UNNUMBERED
,
304 .procname
= "sched_compat_yield",
305 .data
= &sysctl_sched_compat_yield
,
306 .maxlen
= sizeof(unsigned int),
308 .proc_handler
= &proc_dointvec
,
310 #ifdef CONFIG_PROVE_LOCKING
312 .ctl_name
= CTL_UNNUMBERED
,
313 .procname
= "prove_locking",
314 .data
= &prove_locking
,
315 .maxlen
= sizeof(int),
317 .proc_handler
= &proc_dointvec
,
320 #ifdef CONFIG_LOCK_STAT
322 .ctl_name
= CTL_UNNUMBERED
,
323 .procname
= "lock_stat",
325 .maxlen
= sizeof(int),
327 .proc_handler
= &proc_dointvec
,
331 .ctl_name
= KERN_PANIC
,
333 .data
= &panic_timeout
,
334 .maxlen
= sizeof(int),
336 .proc_handler
= &proc_dointvec
,
339 .ctl_name
= KERN_CORE_USES_PID
,
340 .procname
= "core_uses_pid",
341 .data
= &core_uses_pid
,
342 .maxlen
= sizeof(int),
344 .proc_handler
= &proc_dointvec
,
346 #ifdef CONFIG_AUDITSYSCALL
348 .ctl_name
= CTL_UNNUMBERED
,
349 .procname
= "audit_argv_kb",
350 .data
= &audit_argv_kb
,
351 .maxlen
= sizeof(int),
353 .proc_handler
= &proc_dointvec
,
357 .ctl_name
= KERN_CORE_PATTERN
,
358 .procname
= "core_pattern",
359 .data
= core_pattern
,
360 .maxlen
= CORENAME_MAX_SIZE
,
362 .proc_handler
= &proc_dostring
,
363 .strategy
= &sysctl_string
,
365 #ifdef CONFIG_PROC_SYSCTL
367 .procname
= "tainted",
369 .maxlen
= sizeof(int),
371 .proc_handler
= &proc_dointvec_taint
,
374 #ifdef CONFIG_SECURITY_CAPABILITIES
376 .procname
= "cap-bound",
378 .maxlen
= sizeof(kernel_cap_t
),
380 .proc_handler
= &proc_dointvec_bset
,
382 #endif /* def CONFIG_SECURITY_CAPABILITIES */
383 #ifdef CONFIG_BLK_DEV_INITRD
385 .ctl_name
= KERN_REALROOTDEV
,
386 .procname
= "real-root-dev",
387 .data
= &real_root_dev
,
388 .maxlen
= sizeof(int),
390 .proc_handler
= &proc_dointvec
,
394 .ctl_name
= CTL_UNNUMBERED
,
395 .procname
= "print-fatal-signals",
396 .data
= &print_fatal_signals
,
397 .maxlen
= sizeof(int),
399 .proc_handler
= &proc_dointvec
,
403 .ctl_name
= KERN_SPARC_REBOOT
,
404 .procname
= "reboot-cmd",
405 .data
= reboot_command
,
408 .proc_handler
= &proc_dostring
,
409 .strategy
= &sysctl_string
,
412 .ctl_name
= KERN_SPARC_STOP_A
,
413 .procname
= "stop-a",
414 .data
= &stop_a_enabled
,
415 .maxlen
= sizeof (int),
417 .proc_handler
= &proc_dointvec
,
420 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
421 .procname
= "scons-poweroff",
422 .data
= &scons_pwroff
,
423 .maxlen
= sizeof (int),
425 .proc_handler
= &proc_dointvec
,
430 .ctl_name
= KERN_HPPA_PWRSW
,
431 .procname
= "soft-power",
432 .data
= &pwrsw_enabled
,
433 .maxlen
= sizeof (int),
435 .proc_handler
= &proc_dointvec
,
438 .ctl_name
= KERN_HPPA_UNALIGNED
,
439 .procname
= "unaligned-trap",
440 .data
= &unaligned_enabled
,
441 .maxlen
= sizeof (int),
443 .proc_handler
= &proc_dointvec
,
447 .ctl_name
= KERN_CTLALTDEL
,
448 .procname
= "ctrl-alt-del",
450 .maxlen
= sizeof(int),
452 .proc_handler
= &proc_dointvec
,
455 .ctl_name
= KERN_PRINTK
,
456 .procname
= "printk",
457 .data
= &console_loglevel
,
458 .maxlen
= 4*sizeof(int),
460 .proc_handler
= &proc_dointvec
,
464 .ctl_name
= KERN_MODPROBE
,
465 .procname
= "modprobe",
466 .data
= &modprobe_path
,
467 .maxlen
= KMOD_PATH_LEN
,
469 .proc_handler
= &proc_dostring
,
470 .strategy
= &sysctl_string
,
473 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
475 .ctl_name
= KERN_HOTPLUG
,
476 .procname
= "hotplug",
477 .data
= &uevent_helper
,
478 .maxlen
= UEVENT_HELPER_PATH_LEN
,
480 .proc_handler
= &proc_dostring
,
481 .strategy
= &sysctl_string
,
484 #ifdef CONFIG_CHR_DEV_SG
486 .ctl_name
= KERN_SG_BIG_BUFF
,
487 .procname
= "sg-big-buff",
488 .data
= &sg_big_buff
,
489 .maxlen
= sizeof (int),
491 .proc_handler
= &proc_dointvec
,
494 #ifdef CONFIG_BSD_PROCESS_ACCT
496 .ctl_name
= KERN_ACCT
,
499 .maxlen
= 3*sizeof(int),
501 .proc_handler
= &proc_dointvec
,
504 #ifdef CONFIG_MAGIC_SYSRQ
506 .ctl_name
= KERN_SYSRQ
,
508 .data
= &__sysrq_enabled
,
509 .maxlen
= sizeof (int),
511 .proc_handler
= &proc_dointvec
,
514 #ifdef CONFIG_PROC_SYSCTL
516 .procname
= "cad_pid",
518 .maxlen
= sizeof (int),
520 .proc_handler
= &proc_do_cad_pid
,
524 .ctl_name
= KERN_MAX_THREADS
,
525 .procname
= "threads-max",
526 .data
= &max_threads
,
527 .maxlen
= sizeof(int),
529 .proc_handler
= &proc_dointvec
,
532 .ctl_name
= KERN_RANDOM
,
533 .procname
= "random",
535 .child
= random_table
,
538 .ctl_name
= KERN_OVERFLOWUID
,
539 .procname
= "overflowuid",
540 .data
= &overflowuid
,
541 .maxlen
= sizeof(int),
543 .proc_handler
= &proc_dointvec_minmax
,
544 .strategy
= &sysctl_intvec
,
545 .extra1
= &minolduid
,
546 .extra2
= &maxolduid
,
549 .ctl_name
= KERN_OVERFLOWGID
,
550 .procname
= "overflowgid",
551 .data
= &overflowgid
,
552 .maxlen
= sizeof(int),
554 .proc_handler
= &proc_dointvec_minmax
,
555 .strategy
= &sysctl_intvec
,
556 .extra1
= &minolduid
,
557 .extra2
= &maxolduid
,
560 #ifdef CONFIG_MATHEMU
562 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
563 .procname
= "ieee_emulation_warnings",
564 .data
= &sysctl_ieee_emulation_warnings
,
565 .maxlen
= sizeof(int),
567 .proc_handler
= &proc_dointvec
,
570 #ifdef CONFIG_NO_IDLE_HZ
572 .ctl_name
= KERN_HZ_TIMER
,
573 .procname
= "hz_timer",
574 .data
= &sysctl_hz_timer
,
575 .maxlen
= sizeof(int),
577 .proc_handler
= &proc_dointvec
,
581 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
582 .procname
= "userprocess_debug",
583 .data
= &sysctl_userprocess_debug
,
584 .maxlen
= sizeof(int),
586 .proc_handler
= &proc_dointvec
,
590 .ctl_name
= KERN_PIDMAX
,
591 .procname
= "pid_max",
593 .maxlen
= sizeof (int),
595 .proc_handler
= &proc_dointvec_minmax
,
596 .strategy
= sysctl_intvec
,
597 .extra1
= &pid_max_min
,
598 .extra2
= &pid_max_max
,
601 .ctl_name
= KERN_PANIC_ON_OOPS
,
602 .procname
= "panic_on_oops",
603 .data
= &panic_on_oops
,
604 .maxlen
= sizeof(int),
606 .proc_handler
= &proc_dointvec
,
609 .ctl_name
= KERN_PRINTK_RATELIMIT
,
610 .procname
= "printk_ratelimit",
611 .data
= &printk_ratelimit_jiffies
,
612 .maxlen
= sizeof(int),
614 .proc_handler
= &proc_dointvec_jiffies
,
615 .strategy
= &sysctl_jiffies
,
618 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
619 .procname
= "printk_ratelimit_burst",
620 .data
= &printk_ratelimit_burst
,
621 .maxlen
= sizeof(int),
623 .proc_handler
= &proc_dointvec
,
626 .ctl_name
= KERN_NGROUPS_MAX
,
627 .procname
= "ngroups_max",
628 .data
= &ngroups_max
,
629 .maxlen
= sizeof (int),
631 .proc_handler
= &proc_dointvec
,
633 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
635 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
636 .procname
= "unknown_nmi_panic",
637 .data
= &unknown_nmi_panic
,
638 .maxlen
= sizeof (int),
640 .proc_handler
= &proc_dointvec
,
643 .procname
= "nmi_watchdog",
644 .data
= &nmi_watchdog_enabled
,
645 .maxlen
= sizeof (int),
647 .proc_handler
= &proc_nmi_enabled
,
650 #if defined(CONFIG_X86)
652 .ctl_name
= KERN_PANIC_ON_NMI
,
653 .procname
= "panic_on_unrecovered_nmi",
654 .data
= &panic_on_unrecovered_nmi
,
655 .maxlen
= sizeof(int),
657 .proc_handler
= &proc_dointvec
,
660 .ctl_name
= KERN_BOOTLOADER_TYPE
,
661 .procname
= "bootloader_type",
662 .data
= &bootloader_type
,
663 .maxlen
= sizeof (int),
665 .proc_handler
= &proc_dointvec
,
668 .ctl_name
= CTL_UNNUMBERED
,
669 .procname
= "kstack_depth_to_print",
670 .data
= &kstack_depth_to_print
,
671 .maxlen
= sizeof(int),
673 .proc_handler
= &proc_dointvec
,
676 #if defined(CONFIG_MMU)
678 .ctl_name
= KERN_RANDOMIZE
,
679 .procname
= "randomize_va_space",
680 .data
= &randomize_va_space
,
681 .maxlen
= sizeof(int),
683 .proc_handler
= &proc_dointvec
,
686 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
688 .ctl_name
= KERN_SPIN_RETRY
,
689 .procname
= "spin_retry",
691 .maxlen
= sizeof (int),
693 .proc_handler
= &proc_dointvec
,
696 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
698 .procname
= "acpi_video_flags",
699 .data
= &acpi_realmode_flags
,
700 .maxlen
= sizeof (unsigned long),
702 .proc_handler
= &proc_doulongvec_minmax
,
707 .ctl_name
= KERN_IA64_UNALIGNED
,
708 .procname
= "ignore-unaligned-usertrap",
709 .data
= &no_unaligned_warning
,
710 .maxlen
= sizeof (int),
712 .proc_handler
= &proc_dointvec
,
715 #ifdef CONFIG_DETECT_SOFTLOCKUP
717 .ctl_name
= CTL_UNNUMBERED
,
718 .procname
= "softlockup_thresh",
719 .data
= &softlockup_thresh
,
720 .maxlen
= sizeof(int),
722 .proc_handler
= &proc_dointvec_minmax
,
723 .strategy
= &sysctl_intvec
,
730 .ctl_name
= KERN_COMPAT_LOG
,
731 .procname
= "compat-log",
733 .maxlen
= sizeof (int),
735 .proc_handler
= &proc_dointvec
,
738 #ifdef CONFIG_RT_MUTEXES
740 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
741 .procname
= "max_lock_depth",
742 .data
= &max_lock_depth
,
743 .maxlen
= sizeof(int),
745 .proc_handler
= &proc_dointvec
,
748 #ifdef CONFIG_PROC_FS
750 .ctl_name
= CTL_UNNUMBERED
,
751 .procname
= "maps_protect",
752 .data
= &maps_protect
,
753 .maxlen
= sizeof(int),
755 .proc_handler
= &proc_dointvec
,
759 .ctl_name
= CTL_UNNUMBERED
,
760 .procname
= "poweroff_cmd",
761 .data
= &poweroff_cmd
,
762 .maxlen
= POWEROFF_CMD_PATH_LEN
,
764 .proc_handler
= &proc_dostring
,
765 .strategy
= &sysctl_string
,
768 * NOTE: do not add new entries to this table unless you have read
769 * Documentation/sysctl/ctl_unnumbered.txt
774 static struct ctl_table vm_table
[] = {
776 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
777 .procname
= "overcommit_memory",
778 .data
= &sysctl_overcommit_memory
,
779 .maxlen
= sizeof(sysctl_overcommit_memory
),
781 .proc_handler
= &proc_dointvec
,
784 .ctl_name
= VM_PANIC_ON_OOM
,
785 .procname
= "panic_on_oom",
786 .data
= &sysctl_panic_on_oom
,
787 .maxlen
= sizeof(sysctl_panic_on_oom
),
789 .proc_handler
= &proc_dointvec
,
792 .ctl_name
= CTL_UNNUMBERED
,
793 .procname
= "oom_kill_allocating_task",
794 .data
= &sysctl_oom_kill_allocating_task
,
795 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
797 .proc_handler
= &proc_dointvec
,
800 .ctl_name
= VM_OVERCOMMIT_RATIO
,
801 .procname
= "overcommit_ratio",
802 .data
= &sysctl_overcommit_ratio
,
803 .maxlen
= sizeof(sysctl_overcommit_ratio
),
805 .proc_handler
= &proc_dointvec
,
808 .ctl_name
= VM_PAGE_CLUSTER
,
809 .procname
= "page-cluster",
810 .data
= &page_cluster
,
811 .maxlen
= sizeof(int),
813 .proc_handler
= &proc_dointvec
,
816 .ctl_name
= VM_DIRTY_BACKGROUND
,
817 .procname
= "dirty_background_ratio",
818 .data
= &dirty_background_ratio
,
819 .maxlen
= sizeof(dirty_background_ratio
),
821 .proc_handler
= &proc_dointvec_minmax
,
822 .strategy
= &sysctl_intvec
,
824 .extra2
= &one_hundred
,
827 .ctl_name
= VM_DIRTY_RATIO
,
828 .procname
= "dirty_ratio",
829 .data
= &vm_dirty_ratio
,
830 .maxlen
= sizeof(vm_dirty_ratio
),
832 .proc_handler
= &dirty_ratio_handler
,
833 .strategy
= &sysctl_intvec
,
835 .extra2
= &one_hundred
,
838 .procname
= "dirty_writeback_centisecs",
839 .data
= &dirty_writeback_interval
,
840 .maxlen
= sizeof(dirty_writeback_interval
),
842 .proc_handler
= &dirty_writeback_centisecs_handler
,
845 .procname
= "dirty_expire_centisecs",
846 .data
= &dirty_expire_interval
,
847 .maxlen
= sizeof(dirty_expire_interval
),
849 .proc_handler
= &proc_dointvec_userhz_jiffies
,
852 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
853 .procname
= "nr_pdflush_threads",
854 .data
= &nr_pdflush_threads
,
855 .maxlen
= sizeof nr_pdflush_threads
,
856 .mode
= 0444 /* read-only*/,
857 .proc_handler
= &proc_dointvec
,
860 .ctl_name
= VM_SWAPPINESS
,
861 .procname
= "swappiness",
862 .data
= &vm_swappiness
,
863 .maxlen
= sizeof(vm_swappiness
),
865 .proc_handler
= &proc_dointvec_minmax
,
866 .strategy
= &sysctl_intvec
,
868 .extra2
= &one_hundred
,
870 #ifdef CONFIG_HUGETLB_PAGE
872 .procname
= "nr_hugepages",
873 .data
= &max_huge_pages
,
874 .maxlen
= sizeof(unsigned long),
876 .proc_handler
= &hugetlb_sysctl_handler
,
877 .extra1
= (void *)&hugetlb_zero
,
878 .extra2
= (void *)&hugetlb_infinity
,
881 .ctl_name
= VM_HUGETLB_GROUP
,
882 .procname
= "hugetlb_shm_group",
883 .data
= &sysctl_hugetlb_shm_group
,
884 .maxlen
= sizeof(gid_t
),
886 .proc_handler
= &proc_dointvec
,
889 .ctl_name
= CTL_UNNUMBERED
,
890 .procname
= "hugepages_treat_as_movable",
891 .data
= &hugepages_treat_as_movable
,
892 .maxlen
= sizeof(int),
894 .proc_handler
= &hugetlb_treat_movable_handler
,
897 .ctl_name
= CTL_UNNUMBERED
,
898 .procname
= "hugetlb_dynamic_pool",
899 .data
= &hugetlb_dynamic_pool
,
900 .maxlen
= sizeof(hugetlb_dynamic_pool
),
902 .proc_handler
= &proc_dointvec
,
906 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
907 .procname
= "lowmem_reserve_ratio",
908 .data
= &sysctl_lowmem_reserve_ratio
,
909 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
911 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
912 .strategy
= &sysctl_intvec
,
915 .ctl_name
= VM_DROP_PAGECACHE
,
916 .procname
= "drop_caches",
917 .data
= &sysctl_drop_caches
,
918 .maxlen
= sizeof(int),
920 .proc_handler
= drop_caches_sysctl_handler
,
921 .strategy
= &sysctl_intvec
,
924 .ctl_name
= VM_MIN_FREE_KBYTES
,
925 .procname
= "min_free_kbytes",
926 .data
= &min_free_kbytes
,
927 .maxlen
= sizeof(min_free_kbytes
),
929 .proc_handler
= &min_free_kbytes_sysctl_handler
,
930 .strategy
= &sysctl_intvec
,
934 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
935 .procname
= "percpu_pagelist_fraction",
936 .data
= &percpu_pagelist_fraction
,
937 .maxlen
= sizeof(percpu_pagelist_fraction
),
939 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
940 .strategy
= &sysctl_intvec
,
941 .extra1
= &min_percpu_pagelist_fract
,
945 .ctl_name
= VM_MAX_MAP_COUNT
,
946 .procname
= "max_map_count",
947 .data
= &sysctl_max_map_count
,
948 .maxlen
= sizeof(sysctl_max_map_count
),
950 .proc_handler
= &proc_dointvec
954 .ctl_name
= VM_LAPTOP_MODE
,
955 .procname
= "laptop_mode",
956 .data
= &laptop_mode
,
957 .maxlen
= sizeof(laptop_mode
),
959 .proc_handler
= &proc_dointvec_jiffies
,
960 .strategy
= &sysctl_jiffies
,
963 .ctl_name
= VM_BLOCK_DUMP
,
964 .procname
= "block_dump",
966 .maxlen
= sizeof(block_dump
),
968 .proc_handler
= &proc_dointvec
,
969 .strategy
= &sysctl_intvec
,
973 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
974 .procname
= "vfs_cache_pressure",
975 .data
= &sysctl_vfs_cache_pressure
,
976 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
978 .proc_handler
= &proc_dointvec
,
979 .strategy
= &sysctl_intvec
,
982 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
984 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
985 .procname
= "legacy_va_layout",
986 .data
= &sysctl_legacy_va_layout
,
987 .maxlen
= sizeof(sysctl_legacy_va_layout
),
989 .proc_handler
= &proc_dointvec
,
990 .strategy
= &sysctl_intvec
,
996 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
997 .procname
= "zone_reclaim_mode",
998 .data
= &zone_reclaim_mode
,
999 .maxlen
= sizeof(zone_reclaim_mode
),
1001 .proc_handler
= &proc_dointvec
,
1002 .strategy
= &sysctl_intvec
,
1006 .ctl_name
= VM_MIN_UNMAPPED
,
1007 .procname
= "min_unmapped_ratio",
1008 .data
= &sysctl_min_unmapped_ratio
,
1009 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1011 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
1012 .strategy
= &sysctl_intvec
,
1014 .extra2
= &one_hundred
,
1017 .ctl_name
= VM_MIN_SLAB
,
1018 .procname
= "min_slab_ratio",
1019 .data
= &sysctl_min_slab_ratio
,
1020 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1022 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1023 .strategy
= &sysctl_intvec
,
1025 .extra2
= &one_hundred
,
1030 .ctl_name
= CTL_UNNUMBERED
,
1031 .procname
= "stat_interval",
1032 .data
= &sysctl_stat_interval
,
1033 .maxlen
= sizeof(sysctl_stat_interval
),
1035 .proc_handler
= &proc_dointvec_jiffies
,
1036 .strategy
= &sysctl_jiffies
,
1039 #ifdef CONFIG_SECURITY
1041 .ctl_name
= CTL_UNNUMBERED
,
1042 .procname
= "mmap_min_addr",
1043 .data
= &mmap_min_addr
,
1044 .maxlen
= sizeof(unsigned long),
1046 .proc_handler
= &proc_doulongvec_minmax
,
1051 .ctl_name
= CTL_UNNUMBERED
,
1052 .procname
= "numa_zonelist_order",
1053 .data
= &numa_zonelist_order
,
1054 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1056 .proc_handler
= &numa_zonelist_order_handler
,
1057 .strategy
= &sysctl_string
,
1060 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1061 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1063 .ctl_name
= VM_VDSO_ENABLED
,
1064 .procname
= "vdso_enabled",
1065 .data
= &vdso_enabled
,
1066 .maxlen
= sizeof(vdso_enabled
),
1068 .proc_handler
= &proc_dointvec
,
1069 .strategy
= &sysctl_intvec
,
1074 * NOTE: do not add new entries to this table unless you have read
1075 * Documentation/sysctl/ctl_unnumbered.txt
1080 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1081 static struct ctl_table binfmt_misc_table
[] = {
1086 static struct ctl_table fs_table
[] = {
1088 .ctl_name
= FS_NRINODE
,
1089 .procname
= "inode-nr",
1090 .data
= &inodes_stat
,
1091 .maxlen
= 2*sizeof(int),
1093 .proc_handler
= &proc_dointvec
,
1096 .ctl_name
= FS_STATINODE
,
1097 .procname
= "inode-state",
1098 .data
= &inodes_stat
,
1099 .maxlen
= 7*sizeof(int),
1101 .proc_handler
= &proc_dointvec
,
1104 .procname
= "file-nr",
1105 .data
= &files_stat
,
1106 .maxlen
= 3*sizeof(int),
1108 .proc_handler
= &proc_nr_files
,
1111 .ctl_name
= FS_MAXFILE
,
1112 .procname
= "file-max",
1113 .data
= &files_stat
.max_files
,
1114 .maxlen
= sizeof(int),
1116 .proc_handler
= &proc_dointvec
,
1119 .ctl_name
= FS_DENTRY
,
1120 .procname
= "dentry-state",
1121 .data
= &dentry_stat
,
1122 .maxlen
= 6*sizeof(int),
1124 .proc_handler
= &proc_dointvec
,
1127 .ctl_name
= FS_OVERFLOWUID
,
1128 .procname
= "overflowuid",
1129 .data
= &fs_overflowuid
,
1130 .maxlen
= sizeof(int),
1132 .proc_handler
= &proc_dointvec_minmax
,
1133 .strategy
= &sysctl_intvec
,
1134 .extra1
= &minolduid
,
1135 .extra2
= &maxolduid
,
1138 .ctl_name
= FS_OVERFLOWGID
,
1139 .procname
= "overflowgid",
1140 .data
= &fs_overflowgid
,
1141 .maxlen
= sizeof(int),
1143 .proc_handler
= &proc_dointvec_minmax
,
1144 .strategy
= &sysctl_intvec
,
1145 .extra1
= &minolduid
,
1146 .extra2
= &maxolduid
,
1149 .ctl_name
= FS_LEASES
,
1150 .procname
= "leases-enable",
1151 .data
= &leases_enable
,
1152 .maxlen
= sizeof(int),
1154 .proc_handler
= &proc_dointvec
,
1156 #ifdef CONFIG_DNOTIFY
1158 .ctl_name
= FS_DIR_NOTIFY
,
1159 .procname
= "dir-notify-enable",
1160 .data
= &dir_notify_enable
,
1161 .maxlen
= sizeof(int),
1163 .proc_handler
= &proc_dointvec
,
1168 .ctl_name
= FS_LEASE_TIME
,
1169 .procname
= "lease-break-time",
1170 .data
= &lease_break_time
,
1171 .maxlen
= sizeof(int),
1173 .proc_handler
= &proc_dointvec_minmax
,
1174 .strategy
= &sysctl_intvec
,
1179 .procname
= "aio-nr",
1181 .maxlen
= sizeof(aio_nr
),
1183 .proc_handler
= &proc_doulongvec_minmax
,
1186 .procname
= "aio-max-nr",
1187 .data
= &aio_max_nr
,
1188 .maxlen
= sizeof(aio_max_nr
),
1190 .proc_handler
= &proc_doulongvec_minmax
,
1192 #ifdef CONFIG_INOTIFY_USER
1194 .ctl_name
= FS_INOTIFY
,
1195 .procname
= "inotify",
1197 .child
= inotify_table
,
1202 .ctl_name
= KERN_SETUID_DUMPABLE
,
1203 .procname
= "suid_dumpable",
1204 .data
= &suid_dumpable
,
1205 .maxlen
= sizeof(int),
1207 .proc_handler
= &proc_dointvec
,
1209 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1211 .ctl_name
= CTL_UNNUMBERED
,
1212 .procname
= "binfmt_misc",
1214 .child
= binfmt_misc_table
,
1218 * NOTE: do not add new entries to this table unless you have read
1219 * Documentation/sysctl/ctl_unnumbered.txt
1224 static struct ctl_table debug_table
[] = {
1225 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1227 .ctl_name
= CTL_UNNUMBERED
,
1228 .procname
= "exception-trace",
1229 .data
= &show_unhandled_signals
,
1230 .maxlen
= sizeof(int),
1232 .proc_handler
= proc_dointvec
1238 static struct ctl_table dev_table
[] = {
1242 static DEFINE_SPINLOCK(sysctl_lock
);
1244 /* called under sysctl_lock */
1245 static int use_table(struct ctl_table_header
*p
)
1247 if (unlikely(p
->unregistering
))
1253 /* called under sysctl_lock */
1254 static void unuse_table(struct ctl_table_header
*p
)
1257 if (unlikely(p
->unregistering
))
1258 complete(p
->unregistering
);
1261 /* called under sysctl_lock, will reacquire if has to wait */
1262 static void start_unregistering(struct ctl_table_header
*p
)
1265 * if p->used is 0, nobody will ever touch that entry again;
1266 * we'll eliminate all paths to it before dropping sysctl_lock
1268 if (unlikely(p
->used
)) {
1269 struct completion wait
;
1270 init_completion(&wait
);
1271 p
->unregistering
= &wait
;
1272 spin_unlock(&sysctl_lock
);
1273 wait_for_completion(&wait
);
1274 spin_lock(&sysctl_lock
);
1277 * do not remove from the list until nobody holds it; walking the
1278 * list in do_sysctl() relies on that.
1280 list_del_init(&p
->ctl_entry
);
1283 void sysctl_head_finish(struct ctl_table_header
*head
)
1287 spin_lock(&sysctl_lock
);
1289 spin_unlock(&sysctl_lock
);
1292 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1294 struct ctl_table_header
*head
;
1295 struct list_head
*tmp
;
1296 spin_lock(&sysctl_lock
);
1298 tmp
= &prev
->ctl_entry
;
1302 tmp
= &root_table_header
.ctl_entry
;
1304 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1306 if (!use_table(head
))
1308 spin_unlock(&sysctl_lock
);
1312 if (tmp
== &root_table_header
.ctl_entry
)
1315 spin_unlock(&sysctl_lock
);
1319 #ifdef CONFIG_SYSCTL_SYSCALL
1320 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1321 void __user
*newval
, size_t newlen
)
1323 struct ctl_table_header
*head
;
1324 int error
= -ENOTDIR
;
1326 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1330 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1334 for (head
= sysctl_head_next(NULL
); head
;
1335 head
= sysctl_head_next(head
)) {
1336 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1337 newval
, newlen
, head
->ctl_table
);
1338 if (error
!= -ENOTDIR
) {
1339 sysctl_head_finish(head
);
1346 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1348 struct __sysctl_args tmp
;
1351 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1354 error
= deprecated_sysctl_warning(&tmp
);
1359 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1360 tmp
.newval
, tmp
.newlen
);
1365 #endif /* CONFIG_SYSCTL_SYSCALL */
1368 * sysctl_perm does NOT grant the superuser all rights automatically, because
1369 * some sysctl variables are readonly even to root.
1372 static int test_perm(int mode
, int op
)
1376 else if (in_egroup_p(0))
1378 if ((mode
& op
& 0007) == op
)
1383 int sysctl_perm(struct ctl_table
*table
, int op
)
1386 error
= security_sysctl(table
, op
);
1389 return test_perm(table
->mode
, op
);
1392 #ifdef CONFIG_SYSCTL_SYSCALL
1393 static int parse_table(int __user
*name
, int nlen
,
1394 void __user
*oldval
, size_t __user
*oldlenp
,
1395 void __user
*newval
, size_t newlen
,
1396 struct ctl_table
*table
)
1402 if (get_user(n
, name
))
1404 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1405 if (!table
->ctl_name
)
1407 if (n
== table
->ctl_name
) {
1410 if (sysctl_perm(table
, 001))
1414 table
= table
->child
;
1417 error
= do_sysctl_strategy(table
, name
, nlen
,
1426 /* Perform the actual read/write of a sysctl table entry. */
1427 int do_sysctl_strategy (struct ctl_table
*table
,
1428 int __user
*name
, int nlen
,
1429 void __user
*oldval
, size_t __user
*oldlenp
,
1430 void __user
*newval
, size_t newlen
)
1438 if (sysctl_perm(table
, op
))
1441 if (table
->strategy
) {
1442 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1450 /* If there is no strategy routine, or if the strategy returns
1451 * zero, proceed with automatic r/w */
1452 if (table
->data
&& table
->maxlen
) {
1453 rc
= sysctl_data(table
, name
, nlen
, oldval
, oldlenp
,
1460 #endif /* CONFIG_SYSCTL_SYSCALL */
1462 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1464 for (; table
->ctl_name
|| table
->procname
; table
++) {
1465 table
->parent
= parent
;
1467 sysctl_set_parent(table
, table
->child
);
1471 static __init
int sysctl_init(void)
1474 sysctl_set_parent(NULL
, root_table
);
1475 err
= sysctl_check_table(root_table
);
1479 core_initcall(sysctl_init
);
1482 * register_sysctl_table - register a sysctl hierarchy
1483 * @table: the top-level table structure
1485 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1486 * array. An entry with a ctl_name of 0 terminates the table.
1488 * The members of the &struct ctl_table structure are used as follows:
1490 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1491 * must be unique within that level of sysctl
1493 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1494 * enter a sysctl file
1496 * data - a pointer to data for use by proc_handler
1498 * maxlen - the maximum size in bytes of the data
1500 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1502 * child - a pointer to the child sysctl table if this entry is a directory, or
1505 * proc_handler - the text handler routine (described below)
1507 * strategy - the strategy routine (described below)
1509 * de - for internal use by the sysctl routines
1511 * extra1, extra2 - extra pointers usable by the proc handler routines
1513 * Leaf nodes in the sysctl tree will be represented by a single file
1514 * under /proc; non-leaf nodes will be represented by directories.
1516 * sysctl(2) can automatically manage read and write requests through
1517 * the sysctl table. The data and maxlen fields of the ctl_table
1518 * struct enable minimal validation of the values being written to be
1519 * performed, and the mode field allows minimal authentication.
1521 * More sophisticated management can be enabled by the provision of a
1522 * strategy routine with the table entry. This will be called before
1523 * any automatic read or write of the data is performed.
1525 * The strategy routine may return
1527 * < 0 - Error occurred (error is passed to user process)
1529 * 0 - OK - proceed with automatic read or write.
1531 * > 0 - OK - read or write has been done by the strategy routine, so
1532 * return immediately.
1534 * There must be a proc_handler routine for any terminal nodes
1535 * mirrored under /proc/sys (non-terminals are handled by a built-in
1536 * directory handler). Several default handlers are available to
1537 * cover common cases -
1539 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1540 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1541 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1543 * It is the handler's job to read the input buffer from user memory
1544 * and process it. The handler should return 0 on success.
1546 * This routine returns %NULL on a failure to register, and a pointer
1547 * to the table header on success.
1549 struct ctl_table_header
*register_sysctl_table(struct ctl_table
* table
)
1551 struct ctl_table_header
*tmp
;
1552 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1555 tmp
->ctl_table
= table
;
1556 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1558 tmp
->unregistering
= NULL
;
1559 sysctl_set_parent(NULL
, table
);
1560 if (sysctl_check_table(tmp
->ctl_table
)) {
1564 spin_lock(&sysctl_lock
);
1565 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1566 spin_unlock(&sysctl_lock
);
1571 * unregister_sysctl_table - unregister a sysctl table hierarchy
1572 * @header: the header returned from register_sysctl_table
1574 * Unregisters the sysctl table and all children. proc entries may not
1575 * actually be removed until they are no longer used by anyone.
1577 void unregister_sysctl_table(struct ctl_table_header
* header
)
1580 spin_lock(&sysctl_lock
);
1581 start_unregistering(header
);
1582 spin_unlock(&sysctl_lock
);
1586 #else /* !CONFIG_SYSCTL */
1587 struct ctl_table_header
*register_sysctl_table(struct ctl_table
* table
)
1592 void unregister_sysctl_table(struct ctl_table_header
* table
)
1596 #endif /* CONFIG_SYSCTL */
1602 #ifdef CONFIG_PROC_SYSCTL
1604 static int _proc_do_string(void* data
, int maxlen
, int write
,
1605 struct file
*filp
, void __user
*buffer
,
1606 size_t *lenp
, loff_t
*ppos
)
1612 if (!data
|| !maxlen
|| !*lenp
) {
1620 while (len
< *lenp
) {
1621 if (get_user(c
, p
++))
1623 if (c
== 0 || c
== '\n')
1629 if(copy_from_user(data
, buffer
, len
))
1631 ((char *) data
)[len
] = 0;
1649 if(copy_to_user(buffer
, data
, len
))
1652 if(put_user('\n', ((char __user
*) buffer
) + len
))
1663 * proc_dostring - read a string sysctl
1664 * @table: the sysctl table
1665 * @write: %TRUE if this is a write to the sysctl file
1666 * @filp: the file structure
1667 * @buffer: the user buffer
1668 * @lenp: the size of the user buffer
1669 * @ppos: file position
1671 * Reads/writes a string from/to the user buffer. If the kernel
1672 * buffer provided is not large enough to hold the string, the
1673 * string is truncated. The copied string is %NULL-terminated.
1674 * If the string is being read by the user process, it is copied
1675 * and a newline '\n' is added. It is truncated if the buffer is
1678 * Returns 0 on success.
1680 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
1681 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1683 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1684 buffer
, lenp
, ppos
);
1688 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1690 int write
, void *data
)
1693 *valp
= *negp
? -*lvalp
: *lvalp
;
1698 *lvalp
= (unsigned long)-val
;
1701 *lvalp
= (unsigned long)val
;
1707 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
1708 int write
, struct file
*filp
, void __user
*buffer
,
1709 size_t *lenp
, loff_t
*ppos
,
1710 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1711 int write
, void *data
),
1714 #define TMPBUFLEN 21
1715 int *i
, vleft
, first
=1, neg
, val
;
1719 char buf
[TMPBUFLEN
], *p
;
1720 char __user
*s
= buffer
;
1722 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1723 (*ppos
&& !write
)) {
1728 i
= (int *) tbl_data
;
1729 vleft
= table
->maxlen
/ sizeof(*i
);
1733 conv
= do_proc_dointvec_conv
;
1735 for (; left
&& vleft
--; i
++, first
=0) {
1750 if (len
> sizeof(buf
) - 1)
1751 len
= sizeof(buf
) - 1;
1752 if (copy_from_user(buf
, s
, len
))
1756 if (*p
== '-' && left
> 1) {
1760 if (*p
< '0' || *p
> '9')
1763 lval
= simple_strtoul(p
, &p
, 0);
1766 if ((len
< left
) && *p
&& !isspace(*p
))
1773 if (conv(&neg
, &lval
, i
, 1, data
))
1780 if (conv(&neg
, &lval
, i
, 0, data
))
1783 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1787 if(copy_to_user(s
, buf
, len
))
1794 if (!write
&& !first
&& left
) {
1795 if(put_user('\n', s
))
1802 if (get_user(c
, s
++))
1817 static int do_proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
1818 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1819 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1820 int write
, void *data
),
1823 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
1824 buffer
, lenp
, ppos
, conv
, data
);
1828 * proc_dointvec - read a vector of integers
1829 * @table: the sysctl table
1830 * @write: %TRUE if this is a write to the sysctl file
1831 * @filp: the file structure
1832 * @buffer: the user buffer
1833 * @lenp: the size of the user buffer
1834 * @ppos: file position
1836 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1837 * values from/to the user buffer, treated as an ASCII string.
1839 * Returns 0 on success.
1841 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
1842 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1844 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1852 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
1854 int write
, void *data
)
1856 int op
= *(int *)data
;
1858 int val
= *negp
? -*lvalp
: *lvalp
;
1860 case OP_SET
: *valp
= val
; break;
1861 case OP_AND
: *valp
&= val
; break;
1862 case OP_OR
: *valp
|= val
; break;
1868 *lvalp
= (unsigned long)-val
;
1871 *lvalp
= (unsigned long)val
;
1877 #ifdef CONFIG_SECURITY_CAPABILITIES
1879 * init may raise the set.
1882 int proc_dointvec_bset(struct ctl_table
*table
, int write
, struct file
*filp
,
1883 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1887 if (write
&& !capable(CAP_SYS_MODULE
)) {
1891 op
= is_global_init(current
) ? OP_SET
: OP_AND
;
1892 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1893 do_proc_dointvec_bset_conv
,&op
);
1895 #endif /* def CONFIG_SECURITY_CAPABILITIES */
1898 * Taint values can only be increased
1900 static int proc_dointvec_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
1901 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1905 if (write
&& !capable(CAP_SYS_ADMIN
))
1909 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1910 do_proc_dointvec_bset_conv
,&op
);
1913 struct do_proc_dointvec_minmax_conv_param
{
1918 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1920 int write
, void *data
)
1922 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1924 int val
= *negp
? -*lvalp
: *lvalp
;
1925 if ((param
->min
&& *param
->min
> val
) ||
1926 (param
->max
&& *param
->max
< val
))
1933 *lvalp
= (unsigned long)-val
;
1936 *lvalp
= (unsigned long)val
;
1943 * proc_dointvec_minmax - read a vector of integers with min/max values
1944 * @table: the sysctl table
1945 * @write: %TRUE if this is a write to the sysctl file
1946 * @filp: the file structure
1947 * @buffer: the user buffer
1948 * @lenp: the size of the user buffer
1949 * @ppos: file position
1951 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1952 * values from/to the user buffer, treated as an ASCII string.
1954 * This routine will ensure the values are within the range specified by
1955 * table->extra1 (min) and table->extra2 (max).
1957 * Returns 0 on success.
1959 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
1960 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1962 struct do_proc_dointvec_minmax_conv_param param
= {
1963 .min
= (int *) table
->extra1
,
1964 .max
= (int *) table
->extra2
,
1966 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1967 do_proc_dointvec_minmax_conv
, ¶m
);
1970 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
1972 void __user
*buffer
,
1973 size_t *lenp
, loff_t
*ppos
,
1974 unsigned long convmul
,
1975 unsigned long convdiv
)
1977 #define TMPBUFLEN 21
1978 unsigned long *i
, *min
, *max
, val
;
1979 int vleft
, first
=1, neg
;
1981 char buf
[TMPBUFLEN
], *p
;
1982 char __user
*s
= buffer
;
1984 if (!data
|| !table
->maxlen
|| !*lenp
||
1985 (*ppos
&& !write
)) {
1990 i
= (unsigned long *) data
;
1991 min
= (unsigned long *) table
->extra1
;
1992 max
= (unsigned long *) table
->extra2
;
1993 vleft
= table
->maxlen
/ sizeof(unsigned long);
1996 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
2011 if (len
> TMPBUFLEN
-1)
2013 if (copy_from_user(buf
, s
, len
))
2017 if (*p
== '-' && left
> 1) {
2021 if (*p
< '0' || *p
> '9')
2023 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2025 if ((len
< left
) && *p
&& !isspace(*p
))
2034 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2041 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2045 if(copy_to_user(s
, buf
, len
))
2052 if (!write
&& !first
&& left
) {
2053 if(put_user('\n', s
))
2060 if (get_user(c
, s
++))
2075 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2077 void __user
*buffer
,
2078 size_t *lenp
, loff_t
*ppos
,
2079 unsigned long convmul
,
2080 unsigned long convdiv
)
2082 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2083 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2087 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2088 * @table: the sysctl table
2089 * @write: %TRUE if this is a write to the sysctl file
2090 * @filp: the file structure
2091 * @buffer: the user buffer
2092 * @lenp: the size of the user buffer
2093 * @ppos: file position
2095 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2096 * values from/to the user buffer, treated as an ASCII string.
2098 * This routine will ensure the values are within the range specified by
2099 * table->extra1 (min) and table->extra2 (max).
2101 * Returns 0 on success.
2103 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2104 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2106 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2110 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2111 * @table: the sysctl table
2112 * @write: %TRUE if this is a write to the sysctl file
2113 * @filp: the file structure
2114 * @buffer: the user buffer
2115 * @lenp: the size of the user buffer
2116 * @ppos: file position
2118 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2119 * values from/to the user buffer, treated as an ASCII string. The values
2120 * are treated as milliseconds, and converted to jiffies when they are stored.
2122 * This routine will ensure the values are within the range specified by
2123 * table->extra1 (min) and table->extra2 (max).
2125 * Returns 0 on success.
2127 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2129 void __user
*buffer
,
2130 size_t *lenp
, loff_t
*ppos
)
2132 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2133 lenp
, ppos
, HZ
, 1000l);
2137 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2139 int write
, void *data
)
2142 if (*lvalp
> LONG_MAX
/ HZ
)
2144 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2150 lval
= (unsigned long)-val
;
2153 lval
= (unsigned long)val
;
2160 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2162 int write
, void *data
)
2165 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2167 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2173 lval
= (unsigned long)-val
;
2176 lval
= (unsigned long)val
;
2178 *lvalp
= jiffies_to_clock_t(lval
);
2183 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2185 int write
, void *data
)
2188 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2194 lval
= (unsigned long)-val
;
2197 lval
= (unsigned long)val
;
2199 *lvalp
= jiffies_to_msecs(lval
);
2205 * proc_dointvec_jiffies - read a vector of integers as seconds
2206 * @table: the sysctl table
2207 * @write: %TRUE if this is a write to the sysctl file
2208 * @filp: the file structure
2209 * @buffer: the user buffer
2210 * @lenp: the size of the user buffer
2211 * @ppos: file position
2213 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2214 * values from/to the user buffer, treated as an ASCII string.
2215 * The values read are assumed to be in seconds, and are converted into
2218 * Returns 0 on success.
2220 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2221 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2223 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2224 do_proc_dointvec_jiffies_conv
,NULL
);
2228 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2229 * @table: the sysctl table
2230 * @write: %TRUE if this is a write to the sysctl file
2231 * @filp: the file structure
2232 * @buffer: the user buffer
2233 * @lenp: the size of the user buffer
2234 * @ppos: pointer to the file position
2236 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2237 * values from/to the user buffer, treated as an ASCII string.
2238 * The values read are assumed to be in 1/USER_HZ seconds, and
2239 * are converted into jiffies.
2241 * Returns 0 on success.
2243 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2244 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2246 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2247 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2251 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2252 * @table: the sysctl table
2253 * @write: %TRUE if this is a write to the sysctl file
2254 * @filp: the file structure
2255 * @buffer: the user buffer
2256 * @lenp: the size of the user buffer
2257 * @ppos: file position
2258 * @ppos: the current position in the file
2260 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2261 * values from/to the user buffer, treated as an ASCII string.
2262 * The values read are assumed to be in 1/1000 seconds, and
2263 * are converted into jiffies.
2265 * Returns 0 on success.
2267 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2268 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2270 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2271 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2274 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
2275 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2277 struct pid
*new_pid
;
2281 tmp
= pid_nr_ns(cad_pid
, current
->nsproxy
->pid_ns
);
2283 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2284 lenp
, ppos
, NULL
, NULL
);
2288 new_pid
= find_get_pid(tmp
);
2292 put_pid(xchg(&cad_pid
, new_pid
));
2296 #else /* CONFIG_PROC_FS */
2298 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2299 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2304 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2305 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2310 int proc_dointvec_bset(struct ctl_table
*table
, int write
, struct file
*filp
,
2311 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2316 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2317 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2322 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2323 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2328 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2329 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2334 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2335 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2340 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2341 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2346 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2348 void __user
*buffer
,
2349 size_t *lenp
, loff_t
*ppos
)
2355 #endif /* CONFIG_PROC_FS */
2358 #ifdef CONFIG_SYSCTL_SYSCALL
2360 * General sysctl support routines
2363 /* The generic sysctl data routine (used if no strategy routine supplied) */
2364 int sysctl_data(struct ctl_table
*table
, int __user
*name
, int nlen
,
2365 void __user
*oldval
, size_t __user
*oldlenp
,
2366 void __user
*newval
, size_t newlen
)
2370 /* Get out of I don't have a variable */
2371 if (!table
->data
|| !table
->maxlen
)
2374 if (oldval
&& oldlenp
) {
2375 if (get_user(len
, oldlenp
))
2378 if (len
> table
->maxlen
)
2379 len
= table
->maxlen
;
2380 if (copy_to_user(oldval
, table
->data
, len
))
2382 if (put_user(len
, oldlenp
))
2387 if (newval
&& newlen
) {
2388 if (newlen
> table
->maxlen
)
2389 newlen
= table
->maxlen
;
2391 if (copy_from_user(table
->data
, newval
, newlen
))
2397 /* The generic string strategy routine: */
2398 int sysctl_string(struct ctl_table
*table
, int __user
*name
, int nlen
,
2399 void __user
*oldval
, size_t __user
*oldlenp
,
2400 void __user
*newval
, size_t newlen
)
2402 if (!table
->data
|| !table
->maxlen
)
2405 if (oldval
&& oldlenp
) {
2407 if (get_user(bufsize
, oldlenp
))
2410 size_t len
= strlen(table
->data
), copied
;
2412 /* This shouldn't trigger for a well-formed sysctl */
2413 if (len
> table
->maxlen
)
2414 len
= table
->maxlen
;
2416 /* Copy up to a max of bufsize-1 bytes of the string */
2417 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2419 if (copy_to_user(oldval
, table
->data
, copied
) ||
2420 put_user(0, (char __user
*)(oldval
+ copied
)))
2422 if (put_user(len
, oldlenp
))
2426 if (newval
&& newlen
) {
2427 size_t len
= newlen
;
2428 if (len
> table
->maxlen
)
2429 len
= table
->maxlen
;
2430 if(copy_from_user(table
->data
, newval
, len
))
2432 if (len
== table
->maxlen
)
2434 ((char *) table
->data
)[len
] = 0;
2440 * This function makes sure that all of the integers in the vector
2441 * are between the minimum and maximum values given in the arrays
2442 * table->extra1 and table->extra2, respectively.
2444 int sysctl_intvec(struct ctl_table
*table
, int __user
*name
, int nlen
,
2445 void __user
*oldval
, size_t __user
*oldlenp
,
2446 void __user
*newval
, size_t newlen
)
2449 if (newval
&& newlen
) {
2450 int __user
*vec
= (int __user
*) newval
;
2451 int *min
= (int *) table
->extra1
;
2452 int *max
= (int *) table
->extra2
;
2456 if (newlen
% sizeof(int) != 0)
2459 if (!table
->extra1
&& !table
->extra2
)
2462 if (newlen
> table
->maxlen
)
2463 newlen
= table
->maxlen
;
2464 length
= newlen
/ sizeof(int);
2466 for (i
= 0; i
< length
; i
++) {
2468 if (get_user(value
, vec
+ i
))
2470 if (min
&& value
< min
[i
])
2472 if (max
&& value
> max
[i
])
2479 /* Strategy function to convert jiffies to seconds */
2480 int sysctl_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2481 void __user
*oldval
, size_t __user
*oldlenp
,
2482 void __user
*newval
, size_t newlen
)
2484 if (oldval
&& oldlenp
) {
2487 if (get_user(olen
, oldlenp
))
2492 if (olen
< sizeof(int))
2495 val
= *(int *)(table
->data
) / HZ
;
2496 if (put_user(val
, (int __user
*)oldval
))
2498 if (put_user(sizeof(int), oldlenp
))
2502 if (newval
&& newlen
) {
2504 if (newlen
!= sizeof(int))
2506 if (get_user(new, (int __user
*)newval
))
2508 *(int *)(table
->data
) = new*HZ
;
2513 /* Strategy function to convert jiffies to seconds */
2514 int sysctl_ms_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2515 void __user
*oldval
, size_t __user
*oldlenp
,
2516 void __user
*newval
, size_t newlen
)
2518 if (oldval
&& oldlenp
) {
2521 if (get_user(olen
, oldlenp
))
2526 if (olen
< sizeof(int))
2529 val
= jiffies_to_msecs(*(int *)(table
->data
));
2530 if (put_user(val
, (int __user
*)oldval
))
2532 if (put_user(sizeof(int), oldlenp
))
2536 if (newval
&& newlen
) {
2538 if (newlen
!= sizeof(int))
2540 if (get_user(new, (int __user
*)newval
))
2542 *(int *)(table
->data
) = msecs_to_jiffies(new);
2549 #else /* CONFIG_SYSCTL_SYSCALL */
2552 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2554 struct __sysctl_args tmp
;
2557 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2560 error
= deprecated_sysctl_warning(&tmp
);
2562 /* If no error reading the parameters then just -ENOSYS ... */
2569 int sysctl_data(struct ctl_table
*table
, int __user
*name
, int nlen
,
2570 void __user
*oldval
, size_t __user
*oldlenp
,
2571 void __user
*newval
, size_t newlen
)
2576 int sysctl_string(struct ctl_table
*table
, int __user
*name
, int nlen
,
2577 void __user
*oldval
, size_t __user
*oldlenp
,
2578 void __user
*newval
, size_t newlen
)
2583 int sysctl_intvec(struct ctl_table
*table
, int __user
*name
, int nlen
,
2584 void __user
*oldval
, size_t __user
*oldlenp
,
2585 void __user
*newval
, size_t newlen
)
2590 int sysctl_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2591 void __user
*oldval
, size_t __user
*oldlenp
,
2592 void __user
*newval
, size_t newlen
)
2597 int sysctl_ms_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2598 void __user
*oldval
, size_t __user
*oldlenp
,
2599 void __user
*newval
, size_t newlen
)
2604 #endif /* CONFIG_SYSCTL_SYSCALL */
2606 static int deprecated_sysctl_warning(struct __sysctl_args
*args
)
2608 static int msg_count
;
2609 int name
[CTL_MAXNAME
];
2612 /* Read in the sysctl name for better debug message logging */
2613 for (i
= 0; i
< args
->nlen
; i
++)
2614 if (get_user(name
[i
], args
->name
+ i
))
2617 /* Ignore accesses to kernel.version */
2618 if ((args
->nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2621 if (msg_count
< 5) {
2624 "warning: process `%s' used the deprecated sysctl "
2625 "system call with ", current
->comm
);
2626 for (i
= 0; i
< args
->nlen
; i
++)
2627 printk("%d.", name
[i
]);
2634 * No sense putting this after each symbol definition, twice,
2635 * exception granted :-)
2637 EXPORT_SYMBOL(proc_dointvec
);
2638 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2639 EXPORT_SYMBOL(proc_dointvec_minmax
);
2640 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2641 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2642 EXPORT_SYMBOL(proc_dostring
);
2643 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2644 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2645 EXPORT_SYMBOL(register_sysctl_table
);
2646 EXPORT_SYMBOL(sysctl_intvec
);
2647 EXPORT_SYMBOL(sysctl_jiffies
);
2648 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2649 EXPORT_SYMBOL(sysctl_string
);
2650 EXPORT_SYMBOL(sysctl_data
);
2651 EXPORT_SYMBOL(unregister_sysctl_table
);