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/nfs_fs.h>
47 #include <linux/acpi.h>
48 #include <linux/reboot.h>
49 #include <linux/ftrace.h>
51 #include <asm/uaccess.h>
52 #include <asm/processor.h>
56 #include <asm/stacktrace.h>
60 static int deprecated_sysctl_warning(struct __sysctl_args
*args
);
62 #if defined(CONFIG_SYSCTL)
64 /* External variables not in a header file. */
66 extern int print_fatal_signals
;
67 extern int sysctl_overcommit_memory
;
68 extern int sysctl_overcommit_ratio
;
69 extern int sysctl_panic_on_oom
;
70 extern int sysctl_oom_kill_allocating_task
;
71 extern int sysctl_oom_dump_tasks
;
72 extern int max_threads
;
73 extern int core_uses_pid
;
74 extern int suid_dumpable
;
75 extern char core_pattern
[];
77 extern int min_free_kbytes
;
78 extern int pid_max_min
, pid_max_max
;
79 extern int sysctl_drop_caches
;
80 extern int percpu_pagelist_fraction
;
81 extern int compat_log
;
82 extern int maps_protect
;
83 extern int sysctl_stat_interval
;
84 extern int latencytop_enabled
;
85 extern int sysctl_nr_open_min
, sysctl_nr_open_max
;
87 /* Constants used for minimum and maximum */
88 #if defined(CONFIG_DETECT_SOFTLOCKUP) || defined(CONFIG_HIGHMEM)
92 #ifdef CONFIG_DETECT_SOFTLOCKUP
93 static int sixty
= 60;
101 static int one_hundred
= 100;
103 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
104 static int maxolduid
= 65535;
105 static int minolduid
;
106 static int min_percpu_pagelist_fract
= 8;
108 static int ngroups_max
= NGROUPS_MAX
;
111 extern char modprobe_path
[];
113 #ifdef CONFIG_CHR_DEV_SG
114 extern int sg_big_buff
;
118 extern char reboot_command
[];
119 extern int stop_a_enabled
;
120 extern int scons_pwroff
;
124 extern int pwrsw_enabled
;
125 extern int unaligned_enabled
;
129 #ifdef CONFIG_MATHEMU
130 extern int sysctl_ieee_emulation_warnings
;
132 extern int sysctl_userprocess_debug
;
133 extern int spin_retry
;
136 extern int sysctl_hz_timer
;
138 #ifdef CONFIG_BSD_PROCESS_ACCT
139 extern int acct_parm
[];
143 extern int no_unaligned_warning
;
146 #ifdef CONFIG_RT_MUTEXES
147 extern int max_lock_depth
;
150 #ifdef CONFIG_PROC_SYSCTL
151 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
152 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
153 static int proc_dointvec_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
154 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
157 static struct ctl_table root_table
[];
158 static struct ctl_table_root sysctl_table_root
;
159 static struct ctl_table_header root_table_header
= {
160 .ctl_table
= root_table
,
161 .ctl_entry
= LIST_HEAD_INIT(sysctl_table_root
.header_list
),
162 .root
= &sysctl_table_root
,
164 static struct ctl_table_root sysctl_table_root
= {
165 .root_list
= LIST_HEAD_INIT(sysctl_table_root
.root_list
),
166 .header_list
= LIST_HEAD_INIT(root_table_header
.ctl_entry
),
169 static struct ctl_table kern_table
[];
170 static struct ctl_table vm_table
[];
171 static struct ctl_table fs_table
[];
172 static struct ctl_table debug_table
[];
173 static struct ctl_table dev_table
[];
174 extern struct ctl_table random_table
[];
175 #ifdef CONFIG_INOTIFY_USER
176 extern struct ctl_table inotify_table
[];
179 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
180 int sysctl_legacy_va_layout
;
183 extern int prove_locking
;
184 extern int lock_stat
;
186 /* The default sysctl tables: */
188 static struct ctl_table root_table
[] = {
190 .ctl_name
= CTL_KERN
,
191 .procname
= "kernel",
208 .ctl_name
= CTL_DEBUG
,
211 .child
= debug_table
,
220 * NOTE: do not add new entries to this table unless you have read
221 * Documentation/sysctl/ctl_unnumbered.txt
226 #ifdef CONFIG_SCHED_DEBUG
227 static int min_sched_granularity_ns
= 100000; /* 100 usecs */
228 static int max_sched_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
229 static int min_wakeup_granularity_ns
; /* 0 usecs */
230 static int max_wakeup_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
233 static struct ctl_table kern_table
[] = {
234 #ifdef CONFIG_SCHED_DEBUG
236 .ctl_name
= CTL_UNNUMBERED
,
237 .procname
= "sched_min_granularity_ns",
238 .data
= &sysctl_sched_min_granularity
,
239 .maxlen
= sizeof(unsigned int),
241 .proc_handler
= &sched_nr_latency_handler
,
242 .strategy
= &sysctl_intvec
,
243 .extra1
= &min_sched_granularity_ns
,
244 .extra2
= &max_sched_granularity_ns
,
247 .ctl_name
= CTL_UNNUMBERED
,
248 .procname
= "sched_latency_ns",
249 .data
= &sysctl_sched_latency
,
250 .maxlen
= sizeof(unsigned int),
252 .proc_handler
= &sched_nr_latency_handler
,
253 .strategy
= &sysctl_intvec
,
254 .extra1
= &min_sched_granularity_ns
,
255 .extra2
= &max_sched_granularity_ns
,
258 .ctl_name
= CTL_UNNUMBERED
,
259 .procname
= "sched_wakeup_granularity_ns",
260 .data
= &sysctl_sched_wakeup_granularity
,
261 .maxlen
= sizeof(unsigned int),
263 .proc_handler
= &proc_dointvec_minmax
,
264 .strategy
= &sysctl_intvec
,
265 .extra1
= &min_wakeup_granularity_ns
,
266 .extra2
= &max_wakeup_granularity_ns
,
269 .ctl_name
= CTL_UNNUMBERED
,
270 .procname
= "sched_child_runs_first",
271 .data
= &sysctl_sched_child_runs_first
,
272 .maxlen
= sizeof(unsigned int),
274 .proc_handler
= &proc_dointvec
,
277 .ctl_name
= CTL_UNNUMBERED
,
278 .procname
= "sched_features",
279 .data
= &sysctl_sched_features
,
280 .maxlen
= sizeof(unsigned int),
282 .proc_handler
= &proc_dointvec
,
285 .ctl_name
= CTL_UNNUMBERED
,
286 .procname
= "sched_migration_cost",
287 .data
= &sysctl_sched_migration_cost
,
288 .maxlen
= sizeof(unsigned int),
290 .proc_handler
= &proc_dointvec
,
293 .ctl_name
= CTL_UNNUMBERED
,
294 .procname
= "sched_nr_migrate",
295 .data
= &sysctl_sched_nr_migrate
,
296 .maxlen
= sizeof(unsigned int),
298 .proc_handler
= &proc_dointvec
,
302 .ctl_name
= CTL_UNNUMBERED
,
303 .procname
= "sched_rt_period_us",
304 .data
= &sysctl_sched_rt_period
,
305 .maxlen
= sizeof(unsigned int),
307 .proc_handler
= &sched_rt_handler
,
310 .ctl_name
= CTL_UNNUMBERED
,
311 .procname
= "sched_rt_runtime_us",
312 .data
= &sysctl_sched_rt_runtime
,
313 .maxlen
= sizeof(int),
315 .proc_handler
= &sched_rt_handler
,
318 .ctl_name
= CTL_UNNUMBERED
,
319 .procname
= "sched_compat_yield",
320 .data
= &sysctl_sched_compat_yield
,
321 .maxlen
= sizeof(unsigned int),
323 .proc_handler
= &proc_dointvec
,
325 #ifdef CONFIG_PROVE_LOCKING
327 .ctl_name
= CTL_UNNUMBERED
,
328 .procname
= "prove_locking",
329 .data
= &prove_locking
,
330 .maxlen
= sizeof(int),
332 .proc_handler
= &proc_dointvec
,
335 #ifdef CONFIG_LOCK_STAT
337 .ctl_name
= CTL_UNNUMBERED
,
338 .procname
= "lock_stat",
340 .maxlen
= sizeof(int),
342 .proc_handler
= &proc_dointvec
,
346 .ctl_name
= KERN_PANIC
,
348 .data
= &panic_timeout
,
349 .maxlen
= sizeof(int),
351 .proc_handler
= &proc_dointvec
,
354 .ctl_name
= KERN_CORE_USES_PID
,
355 .procname
= "core_uses_pid",
356 .data
= &core_uses_pid
,
357 .maxlen
= sizeof(int),
359 .proc_handler
= &proc_dointvec
,
362 .ctl_name
= KERN_CORE_PATTERN
,
363 .procname
= "core_pattern",
364 .data
= core_pattern
,
365 .maxlen
= CORENAME_MAX_SIZE
,
367 .proc_handler
= &proc_dostring
,
368 .strategy
= &sysctl_string
,
370 #ifdef CONFIG_PROC_SYSCTL
372 .procname
= "tainted",
374 .maxlen
= sizeof(int),
376 .proc_handler
= &proc_dointvec_taint
,
379 #ifdef CONFIG_LATENCYTOP
381 .procname
= "latencytop",
382 .data
= &latencytop_enabled
,
383 .maxlen
= sizeof(int),
385 .proc_handler
= &proc_dointvec
,
388 #ifdef CONFIG_BLK_DEV_INITRD
390 .ctl_name
= KERN_REALROOTDEV
,
391 .procname
= "real-root-dev",
392 .data
= &real_root_dev
,
393 .maxlen
= sizeof(int),
395 .proc_handler
= &proc_dointvec
,
399 .ctl_name
= CTL_UNNUMBERED
,
400 .procname
= "print-fatal-signals",
401 .data
= &print_fatal_signals
,
402 .maxlen
= sizeof(int),
404 .proc_handler
= &proc_dointvec
,
408 .ctl_name
= KERN_SPARC_REBOOT
,
409 .procname
= "reboot-cmd",
410 .data
= reboot_command
,
413 .proc_handler
= &proc_dostring
,
414 .strategy
= &sysctl_string
,
417 .ctl_name
= KERN_SPARC_STOP_A
,
418 .procname
= "stop-a",
419 .data
= &stop_a_enabled
,
420 .maxlen
= sizeof (int),
422 .proc_handler
= &proc_dointvec
,
425 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
426 .procname
= "scons-poweroff",
427 .data
= &scons_pwroff
,
428 .maxlen
= sizeof (int),
430 .proc_handler
= &proc_dointvec
,
435 .ctl_name
= KERN_HPPA_PWRSW
,
436 .procname
= "soft-power",
437 .data
= &pwrsw_enabled
,
438 .maxlen
= sizeof (int),
440 .proc_handler
= &proc_dointvec
,
443 .ctl_name
= KERN_HPPA_UNALIGNED
,
444 .procname
= "unaligned-trap",
445 .data
= &unaligned_enabled
,
446 .maxlen
= sizeof (int),
448 .proc_handler
= &proc_dointvec
,
452 .ctl_name
= KERN_CTLALTDEL
,
453 .procname
= "ctrl-alt-del",
455 .maxlen
= sizeof(int),
457 .proc_handler
= &proc_dointvec
,
461 .ctl_name
= CTL_UNNUMBERED
,
462 .procname
= "ftrace_enabled",
463 .data
= &ftrace_enabled
,
464 .maxlen
= sizeof(int),
466 .proc_handler
= &ftrace_enable_sysctl
,
471 .ctl_name
= KERN_MODPROBE
,
472 .procname
= "modprobe",
473 .data
= &modprobe_path
,
474 .maxlen
= KMOD_PATH_LEN
,
476 .proc_handler
= &proc_dostring
,
477 .strategy
= &sysctl_string
,
480 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
482 .ctl_name
= KERN_HOTPLUG
,
483 .procname
= "hotplug",
484 .data
= &uevent_helper
,
485 .maxlen
= UEVENT_HELPER_PATH_LEN
,
487 .proc_handler
= &proc_dostring
,
488 .strategy
= &sysctl_string
,
491 #ifdef CONFIG_CHR_DEV_SG
493 .ctl_name
= KERN_SG_BIG_BUFF
,
494 .procname
= "sg-big-buff",
495 .data
= &sg_big_buff
,
496 .maxlen
= sizeof (int),
498 .proc_handler
= &proc_dointvec
,
501 #ifdef CONFIG_BSD_PROCESS_ACCT
503 .ctl_name
= KERN_ACCT
,
506 .maxlen
= 3*sizeof(int),
508 .proc_handler
= &proc_dointvec
,
511 #ifdef CONFIG_MAGIC_SYSRQ
513 .ctl_name
= KERN_SYSRQ
,
515 .data
= &__sysrq_enabled
,
516 .maxlen
= sizeof (int),
518 .proc_handler
= &proc_dointvec
,
521 #ifdef CONFIG_PROC_SYSCTL
523 .procname
= "cad_pid",
525 .maxlen
= sizeof (int),
527 .proc_handler
= &proc_do_cad_pid
,
531 .ctl_name
= KERN_MAX_THREADS
,
532 .procname
= "threads-max",
533 .data
= &max_threads
,
534 .maxlen
= sizeof(int),
536 .proc_handler
= &proc_dointvec
,
539 .ctl_name
= KERN_RANDOM
,
540 .procname
= "random",
542 .child
= random_table
,
545 .ctl_name
= KERN_OVERFLOWUID
,
546 .procname
= "overflowuid",
547 .data
= &overflowuid
,
548 .maxlen
= sizeof(int),
550 .proc_handler
= &proc_dointvec_minmax
,
551 .strategy
= &sysctl_intvec
,
552 .extra1
= &minolduid
,
553 .extra2
= &maxolduid
,
556 .ctl_name
= KERN_OVERFLOWGID
,
557 .procname
= "overflowgid",
558 .data
= &overflowgid
,
559 .maxlen
= sizeof(int),
561 .proc_handler
= &proc_dointvec_minmax
,
562 .strategy
= &sysctl_intvec
,
563 .extra1
= &minolduid
,
564 .extra2
= &maxolduid
,
567 #ifdef CONFIG_MATHEMU
569 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
570 .procname
= "ieee_emulation_warnings",
571 .data
= &sysctl_ieee_emulation_warnings
,
572 .maxlen
= sizeof(int),
574 .proc_handler
= &proc_dointvec
,
577 #ifdef CONFIG_NO_IDLE_HZ
579 .ctl_name
= KERN_HZ_TIMER
,
580 .procname
= "hz_timer",
581 .data
= &sysctl_hz_timer
,
582 .maxlen
= sizeof(int),
584 .proc_handler
= &proc_dointvec
,
588 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
589 .procname
= "userprocess_debug",
590 .data
= &sysctl_userprocess_debug
,
591 .maxlen
= sizeof(int),
593 .proc_handler
= &proc_dointvec
,
597 .ctl_name
= KERN_PIDMAX
,
598 .procname
= "pid_max",
600 .maxlen
= sizeof (int),
602 .proc_handler
= &proc_dointvec_minmax
,
603 .strategy
= sysctl_intvec
,
604 .extra1
= &pid_max_min
,
605 .extra2
= &pid_max_max
,
608 .ctl_name
= KERN_PANIC_ON_OOPS
,
609 .procname
= "panic_on_oops",
610 .data
= &panic_on_oops
,
611 .maxlen
= sizeof(int),
613 .proc_handler
= &proc_dointvec
,
615 #if defined CONFIG_PRINTK
617 .ctl_name
= KERN_PRINTK
,
618 .procname
= "printk",
619 .data
= &console_loglevel
,
620 .maxlen
= 4*sizeof(int),
622 .proc_handler
= &proc_dointvec
,
625 .ctl_name
= KERN_PRINTK_RATELIMIT
,
626 .procname
= "printk_ratelimit",
627 .data
= &printk_ratelimit_jiffies
,
628 .maxlen
= sizeof(int),
630 .proc_handler
= &proc_dointvec_jiffies
,
631 .strategy
= &sysctl_jiffies
,
634 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
635 .procname
= "printk_ratelimit_burst",
636 .data
= &printk_ratelimit_burst
,
637 .maxlen
= sizeof(int),
639 .proc_handler
= &proc_dointvec
,
643 .ctl_name
= KERN_NGROUPS_MAX
,
644 .procname
= "ngroups_max",
645 .data
= &ngroups_max
,
646 .maxlen
= sizeof (int),
648 .proc_handler
= &proc_dointvec
,
650 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
652 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
653 .procname
= "unknown_nmi_panic",
654 .data
= &unknown_nmi_panic
,
655 .maxlen
= sizeof (int),
657 .proc_handler
= &proc_dointvec
,
660 .procname
= "nmi_watchdog",
661 .data
= &nmi_watchdog_enabled
,
662 .maxlen
= sizeof (int),
664 .proc_handler
= &proc_nmi_enabled
,
667 #if defined(CONFIG_X86)
669 .ctl_name
= KERN_PANIC_ON_NMI
,
670 .procname
= "panic_on_unrecovered_nmi",
671 .data
= &panic_on_unrecovered_nmi
,
672 .maxlen
= sizeof(int),
674 .proc_handler
= &proc_dointvec
,
677 .ctl_name
= KERN_BOOTLOADER_TYPE
,
678 .procname
= "bootloader_type",
679 .data
= &bootloader_type
,
680 .maxlen
= sizeof (int),
682 .proc_handler
= &proc_dointvec
,
685 .ctl_name
= CTL_UNNUMBERED
,
686 .procname
= "kstack_depth_to_print",
687 .data
= &kstack_depth_to_print
,
688 .maxlen
= sizeof(int),
690 .proc_handler
= &proc_dointvec
,
693 .ctl_name
= CTL_UNNUMBERED
,
694 .procname
= "io_delay_type",
695 .data
= &io_delay_type
,
696 .maxlen
= sizeof(int),
698 .proc_handler
= &proc_dointvec
,
701 #if defined(CONFIG_MMU)
703 .ctl_name
= KERN_RANDOMIZE
,
704 .procname
= "randomize_va_space",
705 .data
= &randomize_va_space
,
706 .maxlen
= sizeof(int),
708 .proc_handler
= &proc_dointvec
,
711 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
713 .ctl_name
= KERN_SPIN_RETRY
,
714 .procname
= "spin_retry",
716 .maxlen
= sizeof (int),
718 .proc_handler
= &proc_dointvec
,
721 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
723 .procname
= "acpi_video_flags",
724 .data
= &acpi_realmode_flags
,
725 .maxlen
= sizeof (unsigned long),
727 .proc_handler
= &proc_doulongvec_minmax
,
732 .ctl_name
= KERN_IA64_UNALIGNED
,
733 .procname
= "ignore-unaligned-usertrap",
734 .data
= &no_unaligned_warning
,
735 .maxlen
= sizeof (int),
737 .proc_handler
= &proc_dointvec
,
740 #ifdef CONFIG_DETECT_SOFTLOCKUP
742 .ctl_name
= CTL_UNNUMBERED
,
743 .procname
= "softlockup_thresh",
744 .data
= &softlockup_thresh
,
745 .maxlen
= sizeof(unsigned long),
747 .proc_handler
= &proc_doulongvec_minmax
,
748 .strategy
= &sysctl_intvec
,
753 .ctl_name
= CTL_UNNUMBERED
,
754 .procname
= "hung_task_check_count",
755 .data
= &sysctl_hung_task_check_count
,
756 .maxlen
= sizeof(unsigned long),
758 .proc_handler
= &proc_doulongvec_minmax
,
759 .strategy
= &sysctl_intvec
,
762 .ctl_name
= CTL_UNNUMBERED
,
763 .procname
= "hung_task_timeout_secs",
764 .data
= &sysctl_hung_task_timeout_secs
,
765 .maxlen
= sizeof(unsigned long),
767 .proc_handler
= &proc_doulongvec_minmax
,
768 .strategy
= &sysctl_intvec
,
771 .ctl_name
= CTL_UNNUMBERED
,
772 .procname
= "hung_task_warnings",
773 .data
= &sysctl_hung_task_warnings
,
774 .maxlen
= sizeof(unsigned long),
776 .proc_handler
= &proc_doulongvec_minmax
,
777 .strategy
= &sysctl_intvec
,
782 .ctl_name
= KERN_COMPAT_LOG
,
783 .procname
= "compat-log",
785 .maxlen
= sizeof (int),
787 .proc_handler
= &proc_dointvec
,
790 #ifdef CONFIG_RT_MUTEXES
792 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
793 .procname
= "max_lock_depth",
794 .data
= &max_lock_depth
,
795 .maxlen
= sizeof(int),
797 .proc_handler
= &proc_dointvec
,
800 #ifdef CONFIG_PROC_FS
802 .ctl_name
= CTL_UNNUMBERED
,
803 .procname
= "maps_protect",
804 .data
= &maps_protect
,
805 .maxlen
= sizeof(int),
807 .proc_handler
= &proc_dointvec
,
811 .ctl_name
= CTL_UNNUMBERED
,
812 .procname
= "poweroff_cmd",
813 .data
= &poweroff_cmd
,
814 .maxlen
= POWEROFF_CMD_PATH_LEN
,
816 .proc_handler
= &proc_dostring
,
817 .strategy
= &sysctl_string
,
821 .ctl_name
= CTL_UNNUMBERED
,
824 .child
= key_sysctls
,
828 * NOTE: do not add new entries to this table unless you have read
829 * Documentation/sysctl/ctl_unnumbered.txt
834 static struct ctl_table vm_table
[] = {
836 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
837 .procname
= "overcommit_memory",
838 .data
= &sysctl_overcommit_memory
,
839 .maxlen
= sizeof(sysctl_overcommit_memory
),
841 .proc_handler
= &proc_dointvec
,
844 .ctl_name
= VM_PANIC_ON_OOM
,
845 .procname
= "panic_on_oom",
846 .data
= &sysctl_panic_on_oom
,
847 .maxlen
= sizeof(sysctl_panic_on_oom
),
849 .proc_handler
= &proc_dointvec
,
852 .ctl_name
= CTL_UNNUMBERED
,
853 .procname
= "oom_kill_allocating_task",
854 .data
= &sysctl_oom_kill_allocating_task
,
855 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
857 .proc_handler
= &proc_dointvec
,
860 .ctl_name
= CTL_UNNUMBERED
,
861 .procname
= "oom_dump_tasks",
862 .data
= &sysctl_oom_dump_tasks
,
863 .maxlen
= sizeof(sysctl_oom_dump_tasks
),
865 .proc_handler
= &proc_dointvec
,
868 .ctl_name
= VM_OVERCOMMIT_RATIO
,
869 .procname
= "overcommit_ratio",
870 .data
= &sysctl_overcommit_ratio
,
871 .maxlen
= sizeof(sysctl_overcommit_ratio
),
873 .proc_handler
= &proc_dointvec
,
876 .ctl_name
= VM_PAGE_CLUSTER
,
877 .procname
= "page-cluster",
878 .data
= &page_cluster
,
879 .maxlen
= sizeof(int),
881 .proc_handler
= &proc_dointvec
,
884 .ctl_name
= VM_DIRTY_BACKGROUND
,
885 .procname
= "dirty_background_ratio",
886 .data
= &dirty_background_ratio
,
887 .maxlen
= sizeof(dirty_background_ratio
),
889 .proc_handler
= &proc_dointvec_minmax
,
890 .strategy
= &sysctl_intvec
,
892 .extra2
= &one_hundred
,
895 .ctl_name
= VM_DIRTY_RATIO
,
896 .procname
= "dirty_ratio",
897 .data
= &vm_dirty_ratio
,
898 .maxlen
= sizeof(vm_dirty_ratio
),
900 .proc_handler
= &dirty_ratio_handler
,
901 .strategy
= &sysctl_intvec
,
903 .extra2
= &one_hundred
,
906 .procname
= "dirty_writeback_centisecs",
907 .data
= &dirty_writeback_interval
,
908 .maxlen
= sizeof(dirty_writeback_interval
),
910 .proc_handler
= &dirty_writeback_centisecs_handler
,
913 .procname
= "dirty_expire_centisecs",
914 .data
= &dirty_expire_interval
,
915 .maxlen
= sizeof(dirty_expire_interval
),
917 .proc_handler
= &proc_dointvec_userhz_jiffies
,
920 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
921 .procname
= "nr_pdflush_threads",
922 .data
= &nr_pdflush_threads
,
923 .maxlen
= sizeof nr_pdflush_threads
,
924 .mode
= 0444 /* read-only*/,
925 .proc_handler
= &proc_dointvec
,
928 .ctl_name
= VM_SWAPPINESS
,
929 .procname
= "swappiness",
930 .data
= &vm_swappiness
,
931 .maxlen
= sizeof(vm_swappiness
),
933 .proc_handler
= &proc_dointvec_minmax
,
934 .strategy
= &sysctl_intvec
,
936 .extra2
= &one_hundred
,
938 #ifdef CONFIG_HUGETLB_PAGE
940 .procname
= "nr_hugepages",
941 .data
= &max_huge_pages
,
942 .maxlen
= sizeof(unsigned long),
944 .proc_handler
= &hugetlb_sysctl_handler
,
945 .extra1
= (void *)&hugetlb_zero
,
946 .extra2
= (void *)&hugetlb_infinity
,
949 .ctl_name
= VM_HUGETLB_GROUP
,
950 .procname
= "hugetlb_shm_group",
951 .data
= &sysctl_hugetlb_shm_group
,
952 .maxlen
= sizeof(gid_t
),
954 .proc_handler
= &proc_dointvec
,
957 .ctl_name
= CTL_UNNUMBERED
,
958 .procname
= "hugepages_treat_as_movable",
959 .data
= &hugepages_treat_as_movable
,
960 .maxlen
= sizeof(int),
962 .proc_handler
= &hugetlb_treat_movable_handler
,
965 .ctl_name
= CTL_UNNUMBERED
,
966 .procname
= "nr_overcommit_hugepages",
967 .data
= &sysctl_overcommit_huge_pages
,
968 .maxlen
= sizeof(sysctl_overcommit_huge_pages
),
970 .proc_handler
= &hugetlb_overcommit_handler
,
974 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
975 .procname
= "lowmem_reserve_ratio",
976 .data
= &sysctl_lowmem_reserve_ratio
,
977 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
979 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
980 .strategy
= &sysctl_intvec
,
983 .ctl_name
= VM_DROP_PAGECACHE
,
984 .procname
= "drop_caches",
985 .data
= &sysctl_drop_caches
,
986 .maxlen
= sizeof(int),
988 .proc_handler
= drop_caches_sysctl_handler
,
989 .strategy
= &sysctl_intvec
,
992 .ctl_name
= VM_MIN_FREE_KBYTES
,
993 .procname
= "min_free_kbytes",
994 .data
= &min_free_kbytes
,
995 .maxlen
= sizeof(min_free_kbytes
),
997 .proc_handler
= &min_free_kbytes_sysctl_handler
,
998 .strategy
= &sysctl_intvec
,
1002 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
1003 .procname
= "percpu_pagelist_fraction",
1004 .data
= &percpu_pagelist_fraction
,
1005 .maxlen
= sizeof(percpu_pagelist_fraction
),
1007 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
1008 .strategy
= &sysctl_intvec
,
1009 .extra1
= &min_percpu_pagelist_fract
,
1013 .ctl_name
= VM_MAX_MAP_COUNT
,
1014 .procname
= "max_map_count",
1015 .data
= &sysctl_max_map_count
,
1016 .maxlen
= sizeof(sysctl_max_map_count
),
1018 .proc_handler
= &proc_dointvec
1022 .ctl_name
= VM_LAPTOP_MODE
,
1023 .procname
= "laptop_mode",
1024 .data
= &laptop_mode
,
1025 .maxlen
= sizeof(laptop_mode
),
1027 .proc_handler
= &proc_dointvec_jiffies
,
1028 .strategy
= &sysctl_jiffies
,
1031 .ctl_name
= VM_BLOCK_DUMP
,
1032 .procname
= "block_dump",
1033 .data
= &block_dump
,
1034 .maxlen
= sizeof(block_dump
),
1036 .proc_handler
= &proc_dointvec
,
1037 .strategy
= &sysctl_intvec
,
1041 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
1042 .procname
= "vfs_cache_pressure",
1043 .data
= &sysctl_vfs_cache_pressure
,
1044 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
1046 .proc_handler
= &proc_dointvec
,
1047 .strategy
= &sysctl_intvec
,
1050 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1052 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
1053 .procname
= "legacy_va_layout",
1054 .data
= &sysctl_legacy_va_layout
,
1055 .maxlen
= sizeof(sysctl_legacy_va_layout
),
1057 .proc_handler
= &proc_dointvec
,
1058 .strategy
= &sysctl_intvec
,
1064 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
1065 .procname
= "zone_reclaim_mode",
1066 .data
= &zone_reclaim_mode
,
1067 .maxlen
= sizeof(zone_reclaim_mode
),
1069 .proc_handler
= &proc_dointvec
,
1070 .strategy
= &sysctl_intvec
,
1074 .ctl_name
= VM_MIN_UNMAPPED
,
1075 .procname
= "min_unmapped_ratio",
1076 .data
= &sysctl_min_unmapped_ratio
,
1077 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1079 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
1080 .strategy
= &sysctl_intvec
,
1082 .extra2
= &one_hundred
,
1085 .ctl_name
= VM_MIN_SLAB
,
1086 .procname
= "min_slab_ratio",
1087 .data
= &sysctl_min_slab_ratio
,
1088 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1090 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1091 .strategy
= &sysctl_intvec
,
1093 .extra2
= &one_hundred
,
1098 .ctl_name
= CTL_UNNUMBERED
,
1099 .procname
= "stat_interval",
1100 .data
= &sysctl_stat_interval
,
1101 .maxlen
= sizeof(sysctl_stat_interval
),
1103 .proc_handler
= &proc_dointvec_jiffies
,
1104 .strategy
= &sysctl_jiffies
,
1107 #ifdef CONFIG_SECURITY
1109 .ctl_name
= CTL_UNNUMBERED
,
1110 .procname
= "mmap_min_addr",
1111 .data
= &mmap_min_addr
,
1112 .maxlen
= sizeof(unsigned long),
1114 .proc_handler
= &proc_doulongvec_minmax
,
1119 .ctl_name
= CTL_UNNUMBERED
,
1120 .procname
= "numa_zonelist_order",
1121 .data
= &numa_zonelist_order
,
1122 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1124 .proc_handler
= &numa_zonelist_order_handler
,
1125 .strategy
= &sysctl_string
,
1128 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1129 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1131 .ctl_name
= VM_VDSO_ENABLED
,
1132 .procname
= "vdso_enabled",
1133 .data
= &vdso_enabled
,
1134 .maxlen
= sizeof(vdso_enabled
),
1136 .proc_handler
= &proc_dointvec
,
1137 .strategy
= &sysctl_intvec
,
1141 #ifdef CONFIG_HIGHMEM
1143 .ctl_name
= CTL_UNNUMBERED
,
1144 .procname
= "highmem_is_dirtyable",
1145 .data
= &vm_highmem_is_dirtyable
,
1146 .maxlen
= sizeof(vm_highmem_is_dirtyable
),
1148 .proc_handler
= &proc_dointvec_minmax
,
1149 .strategy
= &sysctl_intvec
,
1155 * NOTE: do not add new entries to this table unless you have read
1156 * Documentation/sysctl/ctl_unnumbered.txt
1161 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1162 static struct ctl_table binfmt_misc_table
[] = {
1167 static struct ctl_table fs_table
[] = {
1169 .ctl_name
= FS_NRINODE
,
1170 .procname
= "inode-nr",
1171 .data
= &inodes_stat
,
1172 .maxlen
= 2*sizeof(int),
1174 .proc_handler
= &proc_dointvec
,
1177 .ctl_name
= FS_STATINODE
,
1178 .procname
= "inode-state",
1179 .data
= &inodes_stat
,
1180 .maxlen
= 7*sizeof(int),
1182 .proc_handler
= &proc_dointvec
,
1185 .procname
= "file-nr",
1186 .data
= &files_stat
,
1187 .maxlen
= 3*sizeof(int),
1189 .proc_handler
= &proc_nr_files
,
1192 .ctl_name
= FS_MAXFILE
,
1193 .procname
= "file-max",
1194 .data
= &files_stat
.max_files
,
1195 .maxlen
= sizeof(int),
1197 .proc_handler
= &proc_dointvec
,
1200 .ctl_name
= CTL_UNNUMBERED
,
1201 .procname
= "nr_open",
1202 .data
= &sysctl_nr_open
,
1203 .maxlen
= sizeof(int),
1205 .proc_handler
= &proc_dointvec_minmax
,
1206 .extra1
= &sysctl_nr_open_min
,
1207 .extra2
= &sysctl_nr_open_max
,
1210 .ctl_name
= FS_DENTRY
,
1211 .procname
= "dentry-state",
1212 .data
= &dentry_stat
,
1213 .maxlen
= 6*sizeof(int),
1215 .proc_handler
= &proc_dointvec
,
1218 .ctl_name
= FS_OVERFLOWUID
,
1219 .procname
= "overflowuid",
1220 .data
= &fs_overflowuid
,
1221 .maxlen
= sizeof(int),
1223 .proc_handler
= &proc_dointvec_minmax
,
1224 .strategy
= &sysctl_intvec
,
1225 .extra1
= &minolduid
,
1226 .extra2
= &maxolduid
,
1229 .ctl_name
= FS_OVERFLOWGID
,
1230 .procname
= "overflowgid",
1231 .data
= &fs_overflowgid
,
1232 .maxlen
= sizeof(int),
1234 .proc_handler
= &proc_dointvec_minmax
,
1235 .strategy
= &sysctl_intvec
,
1236 .extra1
= &minolduid
,
1237 .extra2
= &maxolduid
,
1240 .ctl_name
= FS_LEASES
,
1241 .procname
= "leases-enable",
1242 .data
= &leases_enable
,
1243 .maxlen
= sizeof(int),
1245 .proc_handler
= &proc_dointvec
,
1247 #ifdef CONFIG_DNOTIFY
1249 .ctl_name
= FS_DIR_NOTIFY
,
1250 .procname
= "dir-notify-enable",
1251 .data
= &dir_notify_enable
,
1252 .maxlen
= sizeof(int),
1254 .proc_handler
= &proc_dointvec
,
1259 .ctl_name
= FS_LEASE_TIME
,
1260 .procname
= "lease-break-time",
1261 .data
= &lease_break_time
,
1262 .maxlen
= sizeof(int),
1264 .proc_handler
= &proc_dointvec_minmax
,
1265 .strategy
= &sysctl_intvec
,
1270 .procname
= "aio-nr",
1272 .maxlen
= sizeof(aio_nr
),
1274 .proc_handler
= &proc_doulongvec_minmax
,
1277 .procname
= "aio-max-nr",
1278 .data
= &aio_max_nr
,
1279 .maxlen
= sizeof(aio_max_nr
),
1281 .proc_handler
= &proc_doulongvec_minmax
,
1283 #ifdef CONFIG_INOTIFY_USER
1285 .ctl_name
= FS_INOTIFY
,
1286 .procname
= "inotify",
1288 .child
= inotify_table
,
1293 .ctl_name
= KERN_SETUID_DUMPABLE
,
1294 .procname
= "suid_dumpable",
1295 .data
= &suid_dumpable
,
1296 .maxlen
= sizeof(int),
1298 .proc_handler
= &proc_dointvec
,
1300 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1302 .ctl_name
= CTL_UNNUMBERED
,
1303 .procname
= "binfmt_misc",
1305 .child
= binfmt_misc_table
,
1309 * NOTE: do not add new entries to this table unless you have read
1310 * Documentation/sysctl/ctl_unnumbered.txt
1315 static struct ctl_table debug_table
[] = {
1316 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1318 .ctl_name
= CTL_UNNUMBERED
,
1319 .procname
= "exception-trace",
1320 .data
= &show_unhandled_signals
,
1321 .maxlen
= sizeof(int),
1323 .proc_handler
= proc_dointvec
1329 static struct ctl_table dev_table
[] = {
1333 static DEFINE_SPINLOCK(sysctl_lock
);
1335 /* called under sysctl_lock */
1336 static int use_table(struct ctl_table_header
*p
)
1338 if (unlikely(p
->unregistering
))
1344 /* called under sysctl_lock */
1345 static void unuse_table(struct ctl_table_header
*p
)
1348 if (unlikely(p
->unregistering
))
1349 complete(p
->unregistering
);
1352 /* called under sysctl_lock, will reacquire if has to wait */
1353 static void start_unregistering(struct ctl_table_header
*p
)
1356 * if p->used is 0, nobody will ever touch that entry again;
1357 * we'll eliminate all paths to it before dropping sysctl_lock
1359 if (unlikely(p
->used
)) {
1360 struct completion wait
;
1361 init_completion(&wait
);
1362 p
->unregistering
= &wait
;
1363 spin_unlock(&sysctl_lock
);
1364 wait_for_completion(&wait
);
1365 spin_lock(&sysctl_lock
);
1368 * do not remove from the list until nobody holds it; walking the
1369 * list in do_sysctl() relies on that.
1371 list_del_init(&p
->ctl_entry
);
1374 void sysctl_head_finish(struct ctl_table_header
*head
)
1378 spin_lock(&sysctl_lock
);
1380 spin_unlock(&sysctl_lock
);
1383 static struct list_head
*
1384 lookup_header_list(struct ctl_table_root
*root
, struct nsproxy
*namespaces
)
1386 struct list_head
*header_list
;
1387 header_list
= &root
->header_list
;
1389 header_list
= root
->lookup(root
, namespaces
);
1393 struct ctl_table_header
*__sysctl_head_next(struct nsproxy
*namespaces
,
1394 struct ctl_table_header
*prev
)
1396 struct ctl_table_root
*root
;
1397 struct list_head
*header_list
;
1398 struct ctl_table_header
*head
;
1399 struct list_head
*tmp
;
1401 spin_lock(&sysctl_lock
);
1404 tmp
= &prev
->ctl_entry
;
1408 tmp
= &root_table_header
.ctl_entry
;
1410 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1412 if (!use_table(head
))
1414 spin_unlock(&sysctl_lock
);
1419 header_list
= lookup_header_list(root
, namespaces
);
1420 if (tmp
!= header_list
)
1424 root
= list_entry(root
->root_list
.next
,
1425 struct ctl_table_root
, root_list
);
1426 if (root
== &sysctl_table_root
)
1428 header_list
= lookup_header_list(root
, namespaces
);
1429 } while (list_empty(header_list
));
1430 tmp
= header_list
->next
;
1433 spin_unlock(&sysctl_lock
);
1437 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1439 return __sysctl_head_next(current
->nsproxy
, prev
);
1442 void register_sysctl_root(struct ctl_table_root
*root
)
1444 spin_lock(&sysctl_lock
);
1445 list_add_tail(&root
->root_list
, &sysctl_table_root
.root_list
);
1446 spin_unlock(&sysctl_lock
);
1449 #ifdef CONFIG_SYSCTL_SYSCALL
1450 /* Perform the actual read/write of a sysctl table entry. */
1451 static int do_sysctl_strategy(struct ctl_table_root
*root
,
1452 struct ctl_table
*table
,
1453 int __user
*name
, int nlen
,
1454 void __user
*oldval
, size_t __user
*oldlenp
,
1455 void __user
*newval
, size_t newlen
)
1463 if (sysctl_perm(root
, table
, op
))
1466 if (table
->strategy
) {
1467 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1475 /* If there is no strategy routine, or if the strategy returns
1476 * zero, proceed with automatic r/w */
1477 if (table
->data
&& table
->maxlen
) {
1478 rc
= sysctl_data(table
, name
, nlen
, oldval
, oldlenp
,
1486 static int parse_table(int __user
*name
, int nlen
,
1487 void __user
*oldval
, size_t __user
*oldlenp
,
1488 void __user
*newval
, size_t newlen
,
1489 struct ctl_table_root
*root
,
1490 struct ctl_table
*table
)
1496 if (get_user(n
, name
))
1498 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1499 if (!table
->ctl_name
)
1501 if (n
== table
->ctl_name
) {
1504 if (sysctl_perm(root
, table
, 001))
1508 table
= table
->child
;
1511 error
= do_sysctl_strategy(root
, table
, name
, nlen
,
1520 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1521 void __user
*newval
, size_t newlen
)
1523 struct ctl_table_header
*head
;
1524 int error
= -ENOTDIR
;
1526 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1530 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1534 for (head
= sysctl_head_next(NULL
); head
;
1535 head
= sysctl_head_next(head
)) {
1536 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1538 head
->root
, head
->ctl_table
);
1539 if (error
!= -ENOTDIR
) {
1540 sysctl_head_finish(head
);
1547 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1549 struct __sysctl_args tmp
;
1552 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1555 error
= deprecated_sysctl_warning(&tmp
);
1560 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1561 tmp
.newval
, tmp
.newlen
);
1566 #endif /* CONFIG_SYSCTL_SYSCALL */
1569 * sysctl_perm does NOT grant the superuser all rights automatically, because
1570 * some sysctl variables are readonly even to root.
1573 static int test_perm(int mode
, int op
)
1577 else if (in_egroup_p(0))
1579 if ((mode
& op
& 0007) == op
)
1584 int sysctl_perm(struct ctl_table_root
*root
, struct ctl_table
*table
, int op
)
1589 error
= security_sysctl(table
, op
);
1593 if (root
->permissions
)
1594 mode
= root
->permissions(root
, current
->nsproxy
, table
);
1598 return test_perm(mode
, op
);
1601 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1603 for (; table
->ctl_name
|| table
->procname
; table
++) {
1604 table
->parent
= parent
;
1606 sysctl_set_parent(table
, table
->child
);
1610 static __init
int sysctl_init(void)
1612 sysctl_set_parent(NULL
, root_table
);
1613 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1616 err
= sysctl_check_table(current
->nsproxy
, root_table
);
1622 core_initcall(sysctl_init
);
1625 * __register_sysctl_paths - register a sysctl hierarchy
1626 * @root: List of sysctl headers to register on
1627 * @namespaces: Data to compute which lists of sysctl entries are visible
1628 * @path: The path to the directory the sysctl table is in.
1629 * @table: the top-level table structure
1631 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1632 * array. A completely 0 filled entry terminates the table.
1634 * The members of the &struct ctl_table structure are used as follows:
1636 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1637 * must be unique within that level of sysctl
1639 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1640 * enter a sysctl file
1642 * data - a pointer to data for use by proc_handler
1644 * maxlen - the maximum size in bytes of the data
1646 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1648 * child - a pointer to the child sysctl table if this entry is a directory, or
1651 * proc_handler - the text handler routine (described below)
1653 * strategy - the strategy routine (described below)
1655 * de - for internal use by the sysctl routines
1657 * extra1, extra2 - extra pointers usable by the proc handler routines
1659 * Leaf nodes in the sysctl tree will be represented by a single file
1660 * under /proc; non-leaf nodes will be represented by directories.
1662 * sysctl(2) can automatically manage read and write requests through
1663 * the sysctl table. The data and maxlen fields of the ctl_table
1664 * struct enable minimal validation of the values being written to be
1665 * performed, and the mode field allows minimal authentication.
1667 * More sophisticated management can be enabled by the provision of a
1668 * strategy routine with the table entry. This will be called before
1669 * any automatic read or write of the data is performed.
1671 * The strategy routine may return
1673 * < 0 - Error occurred (error is passed to user process)
1675 * 0 - OK - proceed with automatic read or write.
1677 * > 0 - OK - read or write has been done by the strategy routine, so
1678 * return immediately.
1680 * There must be a proc_handler routine for any terminal nodes
1681 * mirrored under /proc/sys (non-terminals are handled by a built-in
1682 * directory handler). Several default handlers are available to
1683 * cover common cases -
1685 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1686 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1687 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1689 * It is the handler's job to read the input buffer from user memory
1690 * and process it. The handler should return 0 on success.
1692 * This routine returns %NULL on a failure to register, and a pointer
1693 * to the table header on success.
1695 struct ctl_table_header
*__register_sysctl_paths(
1696 struct ctl_table_root
*root
,
1697 struct nsproxy
*namespaces
,
1698 const struct ctl_path
*path
, struct ctl_table
*table
)
1700 struct list_head
*header_list
;
1701 struct ctl_table_header
*header
;
1702 struct ctl_table
*new, **prevp
;
1703 unsigned int n
, npath
;
1705 /* Count the path components */
1706 for (npath
= 0; path
[npath
].ctl_name
|| path
[npath
].procname
; ++npath
)
1710 * For each path component, allocate a 2-element ctl_table array.
1711 * The first array element will be filled with the sysctl entry
1712 * for this, the second will be the sentinel (ctl_name == 0).
1714 * We allocate everything in one go so that we don't have to
1715 * worry about freeing additional memory in unregister_sysctl_table.
1717 header
= kzalloc(sizeof(struct ctl_table_header
) +
1718 (2 * npath
* sizeof(struct ctl_table
)), GFP_KERNEL
);
1722 new = (struct ctl_table
*) (header
+ 1);
1724 /* Now connect the dots */
1725 prevp
= &header
->ctl_table
;
1726 for (n
= 0; n
< npath
; ++n
, ++path
) {
1727 /* Copy the procname */
1728 new->procname
= path
->procname
;
1729 new->ctl_name
= path
->ctl_name
;
1733 prevp
= &new->child
;
1738 header
->ctl_table_arg
= table
;
1740 INIT_LIST_HEAD(&header
->ctl_entry
);
1742 header
->unregistering
= NULL
;
1743 header
->root
= root
;
1744 sysctl_set_parent(NULL
, header
->ctl_table
);
1745 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1746 if (sysctl_check_table(namespaces
, header
->ctl_table
)) {
1751 spin_lock(&sysctl_lock
);
1752 header_list
= lookup_header_list(root
, namespaces
);
1753 list_add_tail(&header
->ctl_entry
, header_list
);
1754 spin_unlock(&sysctl_lock
);
1760 * register_sysctl_table_path - register a sysctl table hierarchy
1761 * @path: The path to the directory the sysctl table is in.
1762 * @table: the top-level table structure
1764 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1765 * array. A completely 0 filled entry terminates the table.
1767 * See __register_sysctl_paths for more details.
1769 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
1770 struct ctl_table
*table
)
1772 return __register_sysctl_paths(&sysctl_table_root
, current
->nsproxy
,
1777 * register_sysctl_table - register a sysctl table hierarchy
1778 * @table: the top-level table structure
1780 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1781 * array. A completely 0 filled entry terminates the table.
1783 * See register_sysctl_paths for more details.
1785 struct ctl_table_header
*register_sysctl_table(struct ctl_table
*table
)
1787 static const struct ctl_path null_path
[] = { {} };
1789 return register_sysctl_paths(null_path
, table
);
1793 * unregister_sysctl_table - unregister a sysctl table hierarchy
1794 * @header: the header returned from register_sysctl_table
1796 * Unregisters the sysctl table and all children. proc entries may not
1797 * actually be removed until they are no longer used by anyone.
1799 void unregister_sysctl_table(struct ctl_table_header
* header
)
1806 spin_lock(&sysctl_lock
);
1807 start_unregistering(header
);
1808 spin_unlock(&sysctl_lock
);
1812 #else /* !CONFIG_SYSCTL */
1813 struct ctl_table_header
*register_sysctl_table(struct ctl_table
* table
)
1818 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
1819 struct ctl_table
*table
)
1824 void unregister_sysctl_table(struct ctl_table_header
* table
)
1828 #endif /* CONFIG_SYSCTL */
1834 #ifdef CONFIG_PROC_SYSCTL
1836 static int _proc_do_string(void* data
, int maxlen
, int write
,
1837 struct file
*filp
, void __user
*buffer
,
1838 size_t *lenp
, loff_t
*ppos
)
1844 if (!data
|| !maxlen
|| !*lenp
) {
1852 while (len
< *lenp
) {
1853 if (get_user(c
, p
++))
1855 if (c
== 0 || c
== '\n')
1861 if(copy_from_user(data
, buffer
, len
))
1863 ((char *) data
)[len
] = 0;
1881 if(copy_to_user(buffer
, data
, len
))
1884 if(put_user('\n', ((char __user
*) buffer
) + len
))
1895 * proc_dostring - read a string sysctl
1896 * @table: the sysctl table
1897 * @write: %TRUE if this is a write to the sysctl file
1898 * @filp: the file structure
1899 * @buffer: the user buffer
1900 * @lenp: the size of the user buffer
1901 * @ppos: file position
1903 * Reads/writes a string from/to the user buffer. If the kernel
1904 * buffer provided is not large enough to hold the string, the
1905 * string is truncated. The copied string is %NULL-terminated.
1906 * If the string is being read by the user process, it is copied
1907 * and a newline '\n' is added. It is truncated if the buffer is
1910 * Returns 0 on success.
1912 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
1913 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1915 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1916 buffer
, lenp
, ppos
);
1920 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1922 int write
, void *data
)
1925 *valp
= *negp
? -*lvalp
: *lvalp
;
1930 *lvalp
= (unsigned long)-val
;
1933 *lvalp
= (unsigned long)val
;
1939 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
1940 int write
, struct file
*filp
, void __user
*buffer
,
1941 size_t *lenp
, loff_t
*ppos
,
1942 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1943 int write
, void *data
),
1946 #define TMPBUFLEN 21
1947 int *i
, vleft
, first
=1, neg
, val
;
1951 char buf
[TMPBUFLEN
], *p
;
1952 char __user
*s
= buffer
;
1954 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1955 (*ppos
&& !write
)) {
1960 i
= (int *) tbl_data
;
1961 vleft
= table
->maxlen
/ sizeof(*i
);
1965 conv
= do_proc_dointvec_conv
;
1967 for (; left
&& vleft
--; i
++, first
=0) {
1982 if (len
> sizeof(buf
) - 1)
1983 len
= sizeof(buf
) - 1;
1984 if (copy_from_user(buf
, s
, len
))
1988 if (*p
== '-' && left
> 1) {
1992 if (*p
< '0' || *p
> '9')
1995 lval
= simple_strtoul(p
, &p
, 0);
1998 if ((len
< left
) && *p
&& !isspace(*p
))
2005 if (conv(&neg
, &lval
, i
, 1, data
))
2012 if (conv(&neg
, &lval
, i
, 0, data
))
2015 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
2019 if(copy_to_user(s
, buf
, len
))
2026 if (!write
&& !first
&& left
) {
2027 if(put_user('\n', s
))
2034 if (get_user(c
, s
++))
2049 static int do_proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2050 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
2051 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
2052 int write
, void *data
),
2055 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
2056 buffer
, lenp
, ppos
, conv
, data
);
2060 * proc_dointvec - read a vector of integers
2061 * @table: the sysctl table
2062 * @write: %TRUE if this is a write to the sysctl file
2063 * @filp: the file structure
2064 * @buffer: the user buffer
2065 * @lenp: the size of the user buffer
2066 * @ppos: file position
2068 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2069 * values from/to the user buffer, treated as an ASCII string.
2071 * Returns 0 on success.
2073 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2074 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2076 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2084 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
2086 int write
, void *data
)
2088 int op
= *(int *)data
;
2090 int val
= *negp
? -*lvalp
: *lvalp
;
2092 case OP_SET
: *valp
= val
; break;
2093 case OP_AND
: *valp
&= val
; break;
2094 case OP_OR
: *valp
|= val
; break;
2100 *lvalp
= (unsigned long)-val
;
2103 *lvalp
= (unsigned long)val
;
2110 * Taint values can only be increased
2112 static int proc_dointvec_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
2113 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2117 if (write
&& !capable(CAP_SYS_ADMIN
))
2121 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2122 do_proc_dointvec_bset_conv
,&op
);
2125 struct do_proc_dointvec_minmax_conv_param
{
2130 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
2132 int write
, void *data
)
2134 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
2136 int val
= *negp
? -*lvalp
: *lvalp
;
2137 if ((param
->min
&& *param
->min
> val
) ||
2138 (param
->max
&& *param
->max
< val
))
2145 *lvalp
= (unsigned long)-val
;
2148 *lvalp
= (unsigned long)val
;
2155 * proc_dointvec_minmax - read a vector of integers with min/max values
2156 * @table: the sysctl table
2157 * @write: %TRUE if this is a write to the sysctl file
2158 * @filp: the file structure
2159 * @buffer: the user buffer
2160 * @lenp: the size of the user buffer
2161 * @ppos: file position
2163 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2164 * values from/to the user buffer, treated as an ASCII string.
2166 * This routine will ensure the values are within the range specified by
2167 * table->extra1 (min) and table->extra2 (max).
2169 * Returns 0 on success.
2171 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2172 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2174 struct do_proc_dointvec_minmax_conv_param param
= {
2175 .min
= (int *) table
->extra1
,
2176 .max
= (int *) table
->extra2
,
2178 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2179 do_proc_dointvec_minmax_conv
, ¶m
);
2182 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
2184 void __user
*buffer
,
2185 size_t *lenp
, loff_t
*ppos
,
2186 unsigned long convmul
,
2187 unsigned long convdiv
)
2189 #define TMPBUFLEN 21
2190 unsigned long *i
, *min
, *max
, val
;
2191 int vleft
, first
=1, neg
;
2193 char buf
[TMPBUFLEN
], *p
;
2194 char __user
*s
= buffer
;
2196 if (!data
|| !table
->maxlen
|| !*lenp
||
2197 (*ppos
&& !write
)) {
2202 i
= (unsigned long *) data
;
2203 min
= (unsigned long *) table
->extra1
;
2204 max
= (unsigned long *) table
->extra2
;
2205 vleft
= table
->maxlen
/ sizeof(unsigned long);
2208 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
2223 if (len
> TMPBUFLEN
-1)
2225 if (copy_from_user(buf
, s
, len
))
2229 if (*p
== '-' && left
> 1) {
2233 if (*p
< '0' || *p
> '9')
2235 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2237 if ((len
< left
) && *p
&& !isspace(*p
))
2246 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2253 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2257 if(copy_to_user(s
, buf
, len
))
2264 if (!write
&& !first
&& left
) {
2265 if(put_user('\n', s
))
2272 if (get_user(c
, s
++))
2287 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2289 void __user
*buffer
,
2290 size_t *lenp
, loff_t
*ppos
,
2291 unsigned long convmul
,
2292 unsigned long convdiv
)
2294 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2295 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2299 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2300 * @table: the sysctl table
2301 * @write: %TRUE if this is a write to the sysctl file
2302 * @filp: the file structure
2303 * @buffer: the user buffer
2304 * @lenp: the size of the user buffer
2305 * @ppos: file position
2307 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2308 * values from/to the user buffer, treated as an ASCII string.
2310 * This routine will ensure the values are within the range specified by
2311 * table->extra1 (min) and table->extra2 (max).
2313 * Returns 0 on success.
2315 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2316 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2318 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2322 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2323 * @table: the sysctl table
2324 * @write: %TRUE if this is a write to the sysctl file
2325 * @filp: the file structure
2326 * @buffer: the user buffer
2327 * @lenp: the size of the user buffer
2328 * @ppos: file position
2330 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2331 * values from/to the user buffer, treated as an ASCII string. The values
2332 * are treated as milliseconds, and converted to jiffies when they are stored.
2334 * This routine will ensure the values are within the range specified by
2335 * table->extra1 (min) and table->extra2 (max).
2337 * Returns 0 on success.
2339 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2341 void __user
*buffer
,
2342 size_t *lenp
, loff_t
*ppos
)
2344 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2345 lenp
, ppos
, HZ
, 1000l);
2349 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2351 int write
, void *data
)
2354 if (*lvalp
> LONG_MAX
/ HZ
)
2356 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2362 lval
= (unsigned long)-val
;
2365 lval
= (unsigned long)val
;
2372 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2374 int write
, void *data
)
2377 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2379 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2385 lval
= (unsigned long)-val
;
2388 lval
= (unsigned long)val
;
2390 *lvalp
= jiffies_to_clock_t(lval
);
2395 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2397 int write
, void *data
)
2400 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2406 lval
= (unsigned long)-val
;
2409 lval
= (unsigned long)val
;
2411 *lvalp
= jiffies_to_msecs(lval
);
2417 * proc_dointvec_jiffies - read a vector of integers as seconds
2418 * @table: the sysctl table
2419 * @write: %TRUE if this is a write to the sysctl file
2420 * @filp: the file structure
2421 * @buffer: the user buffer
2422 * @lenp: the size of the user buffer
2423 * @ppos: file position
2425 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2426 * values from/to the user buffer, treated as an ASCII string.
2427 * The values read are assumed to be in seconds, and are converted into
2430 * Returns 0 on success.
2432 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2433 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2435 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2436 do_proc_dointvec_jiffies_conv
,NULL
);
2440 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2441 * @table: the sysctl table
2442 * @write: %TRUE if this is a write to the sysctl file
2443 * @filp: the file structure
2444 * @buffer: the user buffer
2445 * @lenp: the size of the user buffer
2446 * @ppos: pointer to the file position
2448 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2449 * values from/to the user buffer, treated as an ASCII string.
2450 * The values read are assumed to be in 1/USER_HZ seconds, and
2451 * are converted into jiffies.
2453 * Returns 0 on success.
2455 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2456 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2458 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2459 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2463 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2464 * @table: the sysctl table
2465 * @write: %TRUE if this is a write to the sysctl file
2466 * @filp: the file structure
2467 * @buffer: the user buffer
2468 * @lenp: the size of the user buffer
2469 * @ppos: file position
2470 * @ppos: the current position in the file
2472 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2473 * values from/to the user buffer, treated as an ASCII string.
2474 * The values read are assumed to be in 1/1000 seconds, and
2475 * are converted into jiffies.
2477 * Returns 0 on success.
2479 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2480 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2482 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2483 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2486 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
2487 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2489 struct pid
*new_pid
;
2493 tmp
= pid_vnr(cad_pid
);
2495 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2496 lenp
, ppos
, NULL
, NULL
);
2500 new_pid
= find_get_pid(tmp
);
2504 put_pid(xchg(&cad_pid
, new_pid
));
2508 #else /* CONFIG_PROC_FS */
2510 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2511 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2516 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2517 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2522 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2523 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2528 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2529 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2534 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2535 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2540 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2541 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2546 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2547 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2552 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2554 void __user
*buffer
,
2555 size_t *lenp
, loff_t
*ppos
)
2561 #endif /* CONFIG_PROC_FS */
2564 #ifdef CONFIG_SYSCTL_SYSCALL
2566 * General sysctl support routines
2569 /* The generic sysctl data routine (used if no strategy routine supplied) */
2570 int sysctl_data(struct ctl_table
*table
, int __user
*name
, int nlen
,
2571 void __user
*oldval
, size_t __user
*oldlenp
,
2572 void __user
*newval
, size_t newlen
)
2576 /* Get out of I don't have a variable */
2577 if (!table
->data
|| !table
->maxlen
)
2580 if (oldval
&& oldlenp
) {
2581 if (get_user(len
, oldlenp
))
2584 if (len
> table
->maxlen
)
2585 len
= table
->maxlen
;
2586 if (copy_to_user(oldval
, table
->data
, len
))
2588 if (put_user(len
, oldlenp
))
2593 if (newval
&& newlen
) {
2594 if (newlen
> table
->maxlen
)
2595 newlen
= table
->maxlen
;
2597 if (copy_from_user(table
->data
, newval
, newlen
))
2603 /* The generic string strategy routine: */
2604 int sysctl_string(struct ctl_table
*table
, int __user
*name
, int nlen
,
2605 void __user
*oldval
, size_t __user
*oldlenp
,
2606 void __user
*newval
, size_t newlen
)
2608 if (!table
->data
|| !table
->maxlen
)
2611 if (oldval
&& oldlenp
) {
2613 if (get_user(bufsize
, oldlenp
))
2616 size_t len
= strlen(table
->data
), copied
;
2618 /* This shouldn't trigger for a well-formed sysctl */
2619 if (len
> table
->maxlen
)
2620 len
= table
->maxlen
;
2622 /* Copy up to a max of bufsize-1 bytes of the string */
2623 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2625 if (copy_to_user(oldval
, table
->data
, copied
) ||
2626 put_user(0, (char __user
*)(oldval
+ copied
)))
2628 if (put_user(len
, oldlenp
))
2632 if (newval
&& newlen
) {
2633 size_t len
= newlen
;
2634 if (len
> table
->maxlen
)
2635 len
= table
->maxlen
;
2636 if(copy_from_user(table
->data
, newval
, len
))
2638 if (len
== table
->maxlen
)
2640 ((char *) table
->data
)[len
] = 0;
2646 * This function makes sure that all of the integers in the vector
2647 * are between the minimum and maximum values given in the arrays
2648 * table->extra1 and table->extra2, respectively.
2650 int sysctl_intvec(struct ctl_table
*table
, int __user
*name
, int nlen
,
2651 void __user
*oldval
, size_t __user
*oldlenp
,
2652 void __user
*newval
, size_t newlen
)
2655 if (newval
&& newlen
) {
2656 int __user
*vec
= (int __user
*) newval
;
2657 int *min
= (int *) table
->extra1
;
2658 int *max
= (int *) table
->extra2
;
2662 if (newlen
% sizeof(int) != 0)
2665 if (!table
->extra1
&& !table
->extra2
)
2668 if (newlen
> table
->maxlen
)
2669 newlen
= table
->maxlen
;
2670 length
= newlen
/ sizeof(int);
2672 for (i
= 0; i
< length
; i
++) {
2674 if (get_user(value
, vec
+ i
))
2676 if (min
&& value
< min
[i
])
2678 if (max
&& value
> max
[i
])
2685 /* Strategy function to convert jiffies to seconds */
2686 int sysctl_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2687 void __user
*oldval
, size_t __user
*oldlenp
,
2688 void __user
*newval
, size_t newlen
)
2690 if (oldval
&& oldlenp
) {
2693 if (get_user(olen
, oldlenp
))
2698 if (olen
< sizeof(int))
2701 val
= *(int *)(table
->data
) / HZ
;
2702 if (put_user(val
, (int __user
*)oldval
))
2704 if (put_user(sizeof(int), oldlenp
))
2708 if (newval
&& newlen
) {
2710 if (newlen
!= sizeof(int))
2712 if (get_user(new, (int __user
*)newval
))
2714 *(int *)(table
->data
) = new*HZ
;
2719 /* Strategy function to convert jiffies to seconds */
2720 int sysctl_ms_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2721 void __user
*oldval
, size_t __user
*oldlenp
,
2722 void __user
*newval
, size_t newlen
)
2724 if (oldval
&& oldlenp
) {
2727 if (get_user(olen
, oldlenp
))
2732 if (olen
< sizeof(int))
2735 val
= jiffies_to_msecs(*(int *)(table
->data
));
2736 if (put_user(val
, (int __user
*)oldval
))
2738 if (put_user(sizeof(int), oldlenp
))
2742 if (newval
&& newlen
) {
2744 if (newlen
!= sizeof(int))
2746 if (get_user(new, (int __user
*)newval
))
2748 *(int *)(table
->data
) = msecs_to_jiffies(new);
2755 #else /* CONFIG_SYSCTL_SYSCALL */
2758 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2760 struct __sysctl_args tmp
;
2763 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2766 error
= deprecated_sysctl_warning(&tmp
);
2768 /* If no error reading the parameters then just -ENOSYS ... */
2775 int sysctl_data(struct ctl_table
*table
, int __user
*name
, int nlen
,
2776 void __user
*oldval
, size_t __user
*oldlenp
,
2777 void __user
*newval
, size_t newlen
)
2782 int sysctl_string(struct ctl_table
*table
, int __user
*name
, int nlen
,
2783 void __user
*oldval
, size_t __user
*oldlenp
,
2784 void __user
*newval
, size_t newlen
)
2789 int sysctl_intvec(struct ctl_table
*table
, int __user
*name
, int nlen
,
2790 void __user
*oldval
, size_t __user
*oldlenp
,
2791 void __user
*newval
, size_t newlen
)
2796 int sysctl_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2797 void __user
*oldval
, size_t __user
*oldlenp
,
2798 void __user
*newval
, size_t newlen
)
2803 int sysctl_ms_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2804 void __user
*oldval
, size_t __user
*oldlenp
,
2805 void __user
*newval
, size_t newlen
)
2810 #endif /* CONFIG_SYSCTL_SYSCALL */
2812 static int deprecated_sysctl_warning(struct __sysctl_args
*args
)
2814 static int msg_count
;
2815 int name
[CTL_MAXNAME
];
2818 /* Check args->nlen. */
2819 if (args
->nlen
< 0 || args
->nlen
> CTL_MAXNAME
)
2822 /* Read in the sysctl name for better debug message logging */
2823 for (i
= 0; i
< args
->nlen
; i
++)
2824 if (get_user(name
[i
], args
->name
+ i
))
2827 /* Ignore accesses to kernel.version */
2828 if ((args
->nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2831 if (msg_count
< 5) {
2834 "warning: process `%s' used the deprecated sysctl "
2835 "system call with ", current
->comm
);
2836 for (i
= 0; i
< args
->nlen
; i
++)
2837 printk("%d.", name
[i
]);
2844 * No sense putting this after each symbol definition, twice,
2845 * exception granted :-)
2847 EXPORT_SYMBOL(proc_dointvec
);
2848 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2849 EXPORT_SYMBOL(proc_dointvec_minmax
);
2850 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2851 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2852 EXPORT_SYMBOL(proc_dostring
);
2853 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2854 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2855 EXPORT_SYMBOL(register_sysctl_table
);
2856 EXPORT_SYMBOL(register_sysctl_paths
);
2857 EXPORT_SYMBOL(sysctl_intvec
);
2858 EXPORT_SYMBOL(sysctl_jiffies
);
2859 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2860 EXPORT_SYMBOL(sysctl_string
);
2861 EXPORT_SYMBOL(sysctl_data
);
2862 EXPORT_SYMBOL(unregister_sysctl_table
);