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>
59 static int deprecated_sysctl_warning(struct __sysctl_args
*args
);
61 #if defined(CONFIG_SYSCTL)
63 /* External variables not in a header file. */
65 extern int print_fatal_signals
;
66 extern int sysctl_overcommit_memory
;
67 extern int sysctl_overcommit_ratio
;
68 extern int sysctl_panic_on_oom
;
69 extern int sysctl_oom_kill_allocating_task
;
70 extern int max_threads
;
71 extern int core_uses_pid
;
72 extern int suid_dumpable
;
73 extern char core_pattern
[];
75 extern int min_free_kbytes
;
76 extern int printk_ratelimit_jiffies
;
77 extern int printk_ratelimit_burst
;
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
;
86 /* Constants used for minimum and maximum */
87 #if defined(CONFIG_DETECT_SOFTLOCKUP) || defined(CONFIG_HIGHMEM)
91 #ifdef CONFIG_DETECT_SOFTLOCKUP
92 static int sixty
= 60;
100 static int one_hundred
= 100;
102 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
103 static int maxolduid
= 65535;
104 static int minolduid
;
105 static int min_percpu_pagelist_fract
= 8;
107 static int ngroups_max
= NGROUPS_MAX
;
110 extern char modprobe_path
[];
112 #ifdef CONFIG_CHR_DEV_SG
113 extern int sg_big_buff
;
117 extern char reboot_command
[];
118 extern int stop_a_enabled
;
119 extern int scons_pwroff
;
123 extern int pwrsw_enabled
;
124 extern int unaligned_enabled
;
128 #ifdef CONFIG_MATHEMU
129 extern int sysctl_ieee_emulation_warnings
;
131 extern int sysctl_userprocess_debug
;
132 extern int spin_retry
;
135 extern int sysctl_hz_timer
;
137 #ifdef CONFIG_BSD_PROCESS_ACCT
138 extern int acct_parm
[];
142 extern int no_unaligned_warning
;
145 #ifdef CONFIG_RT_MUTEXES
146 extern int max_lock_depth
;
149 #ifdef CONFIG_SYSCTL_SYSCALL
150 static int parse_table(int __user
*, int, void __user
*, size_t __user
*,
151 void __user
*, size_t, struct ctl_table
*);
155 #ifdef CONFIG_PROC_SYSCTL
156 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
157 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
158 static int proc_dointvec_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
159 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
162 static struct ctl_table root_table
[];
163 static struct ctl_table_root sysctl_table_root
;
164 static struct ctl_table_header root_table_header
= {
165 .ctl_table
= root_table
,
166 .ctl_entry
= LIST_HEAD_INIT(sysctl_table_root
.header_list
),
167 .root
= &sysctl_table_root
,
169 static struct ctl_table_root sysctl_table_root
= {
170 .root_list
= LIST_HEAD_INIT(sysctl_table_root
.root_list
),
171 .header_list
= LIST_HEAD_INIT(root_table_header
.ctl_entry
),
174 static struct ctl_table kern_table
[];
175 static struct ctl_table vm_table
[];
176 static struct ctl_table fs_table
[];
177 static struct ctl_table debug_table
[];
178 static struct ctl_table dev_table
[];
179 extern struct ctl_table random_table
[];
180 #ifdef CONFIG_INOTIFY_USER
181 extern struct ctl_table inotify_table
[];
184 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
185 int sysctl_legacy_va_layout
;
188 extern int prove_locking
;
189 extern int lock_stat
;
191 /* The default sysctl tables: */
193 static struct ctl_table root_table
[] = {
195 .ctl_name
= CTL_KERN
,
196 .procname
= "kernel",
213 .ctl_name
= CTL_DEBUG
,
216 .child
= debug_table
,
225 * NOTE: do not add new entries to this table unless you have read
226 * Documentation/sysctl/ctl_unnumbered.txt
231 #ifdef CONFIG_SCHED_DEBUG
232 static int min_sched_granularity_ns
= 100000; /* 100 usecs */
233 static int max_sched_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
234 static int min_wakeup_granularity_ns
; /* 0 usecs */
235 static int max_wakeup_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
238 static struct ctl_table kern_table
[] = {
239 #ifdef CONFIG_SCHED_DEBUG
241 .ctl_name
= CTL_UNNUMBERED
,
242 .procname
= "sched_min_granularity_ns",
243 .data
= &sysctl_sched_min_granularity
,
244 .maxlen
= sizeof(unsigned int),
246 .proc_handler
= &sched_nr_latency_handler
,
247 .strategy
= &sysctl_intvec
,
248 .extra1
= &min_sched_granularity_ns
,
249 .extra2
= &max_sched_granularity_ns
,
252 .ctl_name
= CTL_UNNUMBERED
,
253 .procname
= "sched_latency_ns",
254 .data
= &sysctl_sched_latency
,
255 .maxlen
= sizeof(unsigned int),
257 .proc_handler
= &sched_nr_latency_handler
,
258 .strategy
= &sysctl_intvec
,
259 .extra1
= &min_sched_granularity_ns
,
260 .extra2
= &max_sched_granularity_ns
,
263 .ctl_name
= CTL_UNNUMBERED
,
264 .procname
= "sched_wakeup_granularity_ns",
265 .data
= &sysctl_sched_wakeup_granularity
,
266 .maxlen
= sizeof(unsigned int),
268 .proc_handler
= &proc_dointvec_minmax
,
269 .strategy
= &sysctl_intvec
,
270 .extra1
= &min_wakeup_granularity_ns
,
271 .extra2
= &max_wakeup_granularity_ns
,
274 .ctl_name
= CTL_UNNUMBERED
,
275 .procname
= "sched_batch_wakeup_granularity_ns",
276 .data
= &sysctl_sched_batch_wakeup_granularity
,
277 .maxlen
= sizeof(unsigned int),
279 .proc_handler
= &proc_dointvec_minmax
,
280 .strategy
= &sysctl_intvec
,
281 .extra1
= &min_wakeup_granularity_ns
,
282 .extra2
= &max_wakeup_granularity_ns
,
285 .ctl_name
= CTL_UNNUMBERED
,
286 .procname
= "sched_child_runs_first",
287 .data
= &sysctl_sched_child_runs_first
,
288 .maxlen
= sizeof(unsigned int),
290 .proc_handler
= &proc_dointvec
,
293 .ctl_name
= CTL_UNNUMBERED
,
294 .procname
= "sched_features",
295 .data
= &sysctl_sched_features
,
296 .maxlen
= sizeof(unsigned int),
298 .proc_handler
= &proc_dointvec
,
301 .ctl_name
= CTL_UNNUMBERED
,
302 .procname
= "sched_migration_cost",
303 .data
= &sysctl_sched_migration_cost
,
304 .maxlen
= sizeof(unsigned int),
306 .proc_handler
= &proc_dointvec
,
309 .ctl_name
= CTL_UNNUMBERED
,
310 .procname
= "sched_nr_migrate",
311 .data
= &sysctl_sched_nr_migrate
,
312 .maxlen
= sizeof(unsigned int),
314 .proc_handler
= &proc_dointvec
,
317 .ctl_name
= CTL_UNNUMBERED
,
318 .procname
= "sched_rt_period_ms",
319 .data
= &sysctl_sched_rt_period
,
320 .maxlen
= sizeof(unsigned int),
322 .proc_handler
= &proc_dointvec
,
325 .ctl_name
= CTL_UNNUMBERED
,
326 .procname
= "sched_rt_ratio",
327 .data
= &sysctl_sched_rt_ratio
,
328 .maxlen
= sizeof(unsigned int),
330 .proc_handler
= &proc_dointvec
,
332 #if defined(CONFIG_FAIR_GROUP_SCHED) && defined(CONFIG_SMP)
334 .ctl_name
= CTL_UNNUMBERED
,
335 .procname
= "sched_min_bal_int_shares",
336 .data
= &sysctl_sched_min_bal_int_shares
,
337 .maxlen
= sizeof(unsigned int),
339 .proc_handler
= &proc_dointvec
,
342 .ctl_name
= CTL_UNNUMBERED
,
343 .procname
= "sched_max_bal_int_shares",
344 .data
= &sysctl_sched_max_bal_int_shares
,
345 .maxlen
= sizeof(unsigned int),
347 .proc_handler
= &proc_dointvec
,
352 .ctl_name
= CTL_UNNUMBERED
,
353 .procname
= "sched_compat_yield",
354 .data
= &sysctl_sched_compat_yield
,
355 .maxlen
= sizeof(unsigned int),
357 .proc_handler
= &proc_dointvec
,
359 #ifdef CONFIG_PROVE_LOCKING
361 .ctl_name
= CTL_UNNUMBERED
,
362 .procname
= "prove_locking",
363 .data
= &prove_locking
,
364 .maxlen
= sizeof(int),
366 .proc_handler
= &proc_dointvec
,
369 #ifdef CONFIG_LOCK_STAT
371 .ctl_name
= CTL_UNNUMBERED
,
372 .procname
= "lock_stat",
374 .maxlen
= sizeof(int),
376 .proc_handler
= &proc_dointvec
,
380 .ctl_name
= KERN_PANIC
,
382 .data
= &panic_timeout
,
383 .maxlen
= sizeof(int),
385 .proc_handler
= &proc_dointvec
,
388 .ctl_name
= KERN_CORE_USES_PID
,
389 .procname
= "core_uses_pid",
390 .data
= &core_uses_pid
,
391 .maxlen
= sizeof(int),
393 .proc_handler
= &proc_dointvec
,
396 .ctl_name
= KERN_CORE_PATTERN
,
397 .procname
= "core_pattern",
398 .data
= core_pattern
,
399 .maxlen
= CORENAME_MAX_SIZE
,
401 .proc_handler
= &proc_dostring
,
402 .strategy
= &sysctl_string
,
404 #ifdef CONFIG_PROC_SYSCTL
406 .procname
= "tainted",
408 .maxlen
= sizeof(int),
410 .proc_handler
= &proc_dointvec_taint
,
413 #ifdef CONFIG_LATENCYTOP
415 .procname
= "latencytop",
416 .data
= &latencytop_enabled
,
417 .maxlen
= sizeof(int),
419 .proc_handler
= &proc_dointvec
,
422 #ifdef CONFIG_BLK_DEV_INITRD
424 .ctl_name
= KERN_REALROOTDEV
,
425 .procname
= "real-root-dev",
426 .data
= &real_root_dev
,
427 .maxlen
= sizeof(int),
429 .proc_handler
= &proc_dointvec
,
433 .ctl_name
= CTL_UNNUMBERED
,
434 .procname
= "print-fatal-signals",
435 .data
= &print_fatal_signals
,
436 .maxlen
= sizeof(int),
438 .proc_handler
= &proc_dointvec
,
442 .ctl_name
= KERN_SPARC_REBOOT
,
443 .procname
= "reboot-cmd",
444 .data
= reboot_command
,
447 .proc_handler
= &proc_dostring
,
448 .strategy
= &sysctl_string
,
451 .ctl_name
= KERN_SPARC_STOP_A
,
452 .procname
= "stop-a",
453 .data
= &stop_a_enabled
,
454 .maxlen
= sizeof (int),
456 .proc_handler
= &proc_dointvec
,
459 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
460 .procname
= "scons-poweroff",
461 .data
= &scons_pwroff
,
462 .maxlen
= sizeof (int),
464 .proc_handler
= &proc_dointvec
,
469 .ctl_name
= KERN_HPPA_PWRSW
,
470 .procname
= "soft-power",
471 .data
= &pwrsw_enabled
,
472 .maxlen
= sizeof (int),
474 .proc_handler
= &proc_dointvec
,
477 .ctl_name
= KERN_HPPA_UNALIGNED
,
478 .procname
= "unaligned-trap",
479 .data
= &unaligned_enabled
,
480 .maxlen
= sizeof (int),
482 .proc_handler
= &proc_dointvec
,
486 .ctl_name
= KERN_CTLALTDEL
,
487 .procname
= "ctrl-alt-del",
489 .maxlen
= sizeof(int),
491 .proc_handler
= &proc_dointvec
,
494 .ctl_name
= KERN_PRINTK
,
495 .procname
= "printk",
496 .data
= &console_loglevel
,
497 .maxlen
= 4*sizeof(int),
499 .proc_handler
= &proc_dointvec
,
503 .ctl_name
= KERN_MODPROBE
,
504 .procname
= "modprobe",
505 .data
= &modprobe_path
,
506 .maxlen
= KMOD_PATH_LEN
,
508 .proc_handler
= &proc_dostring
,
509 .strategy
= &sysctl_string
,
512 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
514 .ctl_name
= KERN_HOTPLUG
,
515 .procname
= "hotplug",
516 .data
= &uevent_helper
,
517 .maxlen
= UEVENT_HELPER_PATH_LEN
,
519 .proc_handler
= &proc_dostring
,
520 .strategy
= &sysctl_string
,
523 #ifdef CONFIG_CHR_DEV_SG
525 .ctl_name
= KERN_SG_BIG_BUFF
,
526 .procname
= "sg-big-buff",
527 .data
= &sg_big_buff
,
528 .maxlen
= sizeof (int),
530 .proc_handler
= &proc_dointvec
,
533 #ifdef CONFIG_BSD_PROCESS_ACCT
535 .ctl_name
= KERN_ACCT
,
538 .maxlen
= 3*sizeof(int),
540 .proc_handler
= &proc_dointvec
,
543 #ifdef CONFIG_MAGIC_SYSRQ
545 .ctl_name
= KERN_SYSRQ
,
547 .data
= &__sysrq_enabled
,
548 .maxlen
= sizeof (int),
550 .proc_handler
= &proc_dointvec
,
553 #ifdef CONFIG_PROC_SYSCTL
555 .procname
= "cad_pid",
557 .maxlen
= sizeof (int),
559 .proc_handler
= &proc_do_cad_pid
,
563 .ctl_name
= KERN_MAX_THREADS
,
564 .procname
= "threads-max",
565 .data
= &max_threads
,
566 .maxlen
= sizeof(int),
568 .proc_handler
= &proc_dointvec
,
571 .ctl_name
= KERN_RANDOM
,
572 .procname
= "random",
574 .child
= random_table
,
577 .ctl_name
= KERN_OVERFLOWUID
,
578 .procname
= "overflowuid",
579 .data
= &overflowuid
,
580 .maxlen
= sizeof(int),
582 .proc_handler
= &proc_dointvec_minmax
,
583 .strategy
= &sysctl_intvec
,
584 .extra1
= &minolduid
,
585 .extra2
= &maxolduid
,
588 .ctl_name
= KERN_OVERFLOWGID
,
589 .procname
= "overflowgid",
590 .data
= &overflowgid
,
591 .maxlen
= sizeof(int),
593 .proc_handler
= &proc_dointvec_minmax
,
594 .strategy
= &sysctl_intvec
,
595 .extra1
= &minolduid
,
596 .extra2
= &maxolduid
,
599 #ifdef CONFIG_MATHEMU
601 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
602 .procname
= "ieee_emulation_warnings",
603 .data
= &sysctl_ieee_emulation_warnings
,
604 .maxlen
= sizeof(int),
606 .proc_handler
= &proc_dointvec
,
609 #ifdef CONFIG_NO_IDLE_HZ
611 .ctl_name
= KERN_HZ_TIMER
,
612 .procname
= "hz_timer",
613 .data
= &sysctl_hz_timer
,
614 .maxlen
= sizeof(int),
616 .proc_handler
= &proc_dointvec
,
620 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
621 .procname
= "userprocess_debug",
622 .data
= &sysctl_userprocess_debug
,
623 .maxlen
= sizeof(int),
625 .proc_handler
= &proc_dointvec
,
629 .ctl_name
= KERN_PIDMAX
,
630 .procname
= "pid_max",
632 .maxlen
= sizeof (int),
634 .proc_handler
= &proc_dointvec_minmax
,
635 .strategy
= sysctl_intvec
,
636 .extra1
= &pid_max_min
,
637 .extra2
= &pid_max_max
,
640 .ctl_name
= KERN_PANIC_ON_OOPS
,
641 .procname
= "panic_on_oops",
642 .data
= &panic_on_oops
,
643 .maxlen
= sizeof(int),
645 .proc_handler
= &proc_dointvec
,
648 .ctl_name
= KERN_PRINTK_RATELIMIT
,
649 .procname
= "printk_ratelimit",
650 .data
= &printk_ratelimit_jiffies
,
651 .maxlen
= sizeof(int),
653 .proc_handler
= &proc_dointvec_jiffies
,
654 .strategy
= &sysctl_jiffies
,
657 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
658 .procname
= "printk_ratelimit_burst",
659 .data
= &printk_ratelimit_burst
,
660 .maxlen
= sizeof(int),
662 .proc_handler
= &proc_dointvec
,
665 .ctl_name
= KERN_NGROUPS_MAX
,
666 .procname
= "ngroups_max",
667 .data
= &ngroups_max
,
668 .maxlen
= sizeof (int),
670 .proc_handler
= &proc_dointvec
,
672 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
674 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
675 .procname
= "unknown_nmi_panic",
676 .data
= &unknown_nmi_panic
,
677 .maxlen
= sizeof (int),
679 .proc_handler
= &proc_dointvec
,
682 .procname
= "nmi_watchdog",
683 .data
= &nmi_watchdog_enabled
,
684 .maxlen
= sizeof (int),
686 .proc_handler
= &proc_nmi_enabled
,
689 #if defined(CONFIG_X86)
691 .ctl_name
= KERN_PANIC_ON_NMI
,
692 .procname
= "panic_on_unrecovered_nmi",
693 .data
= &panic_on_unrecovered_nmi
,
694 .maxlen
= sizeof(int),
696 .proc_handler
= &proc_dointvec
,
699 .ctl_name
= KERN_BOOTLOADER_TYPE
,
700 .procname
= "bootloader_type",
701 .data
= &bootloader_type
,
702 .maxlen
= sizeof (int),
704 .proc_handler
= &proc_dointvec
,
707 .ctl_name
= CTL_UNNUMBERED
,
708 .procname
= "kstack_depth_to_print",
709 .data
= &kstack_depth_to_print
,
710 .maxlen
= sizeof(int),
712 .proc_handler
= &proc_dointvec
,
715 .ctl_name
= CTL_UNNUMBERED
,
716 .procname
= "io_delay_type",
717 .data
= &io_delay_type
,
718 .maxlen
= sizeof(int),
720 .proc_handler
= &proc_dointvec
,
723 #if defined(CONFIG_MMU)
725 .ctl_name
= KERN_RANDOMIZE
,
726 .procname
= "randomize_va_space",
727 .data
= &randomize_va_space
,
728 .maxlen
= sizeof(int),
730 .proc_handler
= &proc_dointvec
,
733 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
735 .ctl_name
= KERN_SPIN_RETRY
,
736 .procname
= "spin_retry",
738 .maxlen
= sizeof (int),
740 .proc_handler
= &proc_dointvec
,
743 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
745 .procname
= "acpi_video_flags",
746 .data
= &acpi_realmode_flags
,
747 .maxlen
= sizeof (unsigned long),
749 .proc_handler
= &proc_doulongvec_minmax
,
754 .ctl_name
= KERN_IA64_UNALIGNED
,
755 .procname
= "ignore-unaligned-usertrap",
756 .data
= &no_unaligned_warning
,
757 .maxlen
= sizeof (int),
759 .proc_handler
= &proc_dointvec
,
762 #ifdef CONFIG_DETECT_SOFTLOCKUP
764 .ctl_name
= CTL_UNNUMBERED
,
765 .procname
= "softlockup_thresh",
766 .data
= &softlockup_thresh
,
767 .maxlen
= sizeof(unsigned long),
769 .proc_handler
= &proc_doulongvec_minmax
,
770 .strategy
= &sysctl_intvec
,
775 .ctl_name
= CTL_UNNUMBERED
,
776 .procname
= "hung_task_check_count",
777 .data
= &sysctl_hung_task_check_count
,
778 .maxlen
= sizeof(unsigned long),
780 .proc_handler
= &proc_doulongvec_minmax
,
781 .strategy
= &sysctl_intvec
,
784 .ctl_name
= CTL_UNNUMBERED
,
785 .procname
= "hung_task_timeout_secs",
786 .data
= &sysctl_hung_task_timeout_secs
,
787 .maxlen
= sizeof(unsigned long),
789 .proc_handler
= &proc_doulongvec_minmax
,
790 .strategy
= &sysctl_intvec
,
793 .ctl_name
= CTL_UNNUMBERED
,
794 .procname
= "hung_task_warnings",
795 .data
= &sysctl_hung_task_warnings
,
796 .maxlen
= sizeof(unsigned long),
798 .proc_handler
= &proc_doulongvec_minmax
,
799 .strategy
= &sysctl_intvec
,
804 .ctl_name
= KERN_COMPAT_LOG
,
805 .procname
= "compat-log",
807 .maxlen
= sizeof (int),
809 .proc_handler
= &proc_dointvec
,
812 #ifdef CONFIG_RT_MUTEXES
814 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
815 .procname
= "max_lock_depth",
816 .data
= &max_lock_depth
,
817 .maxlen
= sizeof(int),
819 .proc_handler
= &proc_dointvec
,
822 #ifdef CONFIG_PROC_FS
824 .ctl_name
= CTL_UNNUMBERED
,
825 .procname
= "maps_protect",
826 .data
= &maps_protect
,
827 .maxlen
= sizeof(int),
829 .proc_handler
= &proc_dointvec
,
833 .ctl_name
= CTL_UNNUMBERED
,
834 .procname
= "poweroff_cmd",
835 .data
= &poweroff_cmd
,
836 .maxlen
= POWEROFF_CMD_PATH_LEN
,
838 .proc_handler
= &proc_dostring
,
839 .strategy
= &sysctl_string
,
842 * NOTE: do not add new entries to this table unless you have read
843 * Documentation/sysctl/ctl_unnumbered.txt
848 static struct ctl_table vm_table
[] = {
850 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
851 .procname
= "overcommit_memory",
852 .data
= &sysctl_overcommit_memory
,
853 .maxlen
= sizeof(sysctl_overcommit_memory
),
855 .proc_handler
= &proc_dointvec
,
858 .ctl_name
= VM_PANIC_ON_OOM
,
859 .procname
= "panic_on_oom",
860 .data
= &sysctl_panic_on_oom
,
861 .maxlen
= sizeof(sysctl_panic_on_oom
),
863 .proc_handler
= &proc_dointvec
,
866 .ctl_name
= CTL_UNNUMBERED
,
867 .procname
= "oom_kill_allocating_task",
868 .data
= &sysctl_oom_kill_allocating_task
,
869 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
871 .proc_handler
= &proc_dointvec
,
874 .ctl_name
= VM_OVERCOMMIT_RATIO
,
875 .procname
= "overcommit_ratio",
876 .data
= &sysctl_overcommit_ratio
,
877 .maxlen
= sizeof(sysctl_overcommit_ratio
),
879 .proc_handler
= &proc_dointvec
,
882 .ctl_name
= VM_PAGE_CLUSTER
,
883 .procname
= "page-cluster",
884 .data
= &page_cluster
,
885 .maxlen
= sizeof(int),
887 .proc_handler
= &proc_dointvec
,
890 .ctl_name
= VM_DIRTY_BACKGROUND
,
891 .procname
= "dirty_background_ratio",
892 .data
= &dirty_background_ratio
,
893 .maxlen
= sizeof(dirty_background_ratio
),
895 .proc_handler
= &proc_dointvec_minmax
,
896 .strategy
= &sysctl_intvec
,
898 .extra2
= &one_hundred
,
901 .ctl_name
= VM_DIRTY_RATIO
,
902 .procname
= "dirty_ratio",
903 .data
= &vm_dirty_ratio
,
904 .maxlen
= sizeof(vm_dirty_ratio
),
906 .proc_handler
= &dirty_ratio_handler
,
907 .strategy
= &sysctl_intvec
,
909 .extra2
= &one_hundred
,
912 .procname
= "dirty_writeback_centisecs",
913 .data
= &dirty_writeback_interval
,
914 .maxlen
= sizeof(dirty_writeback_interval
),
916 .proc_handler
= &dirty_writeback_centisecs_handler
,
919 .procname
= "dirty_expire_centisecs",
920 .data
= &dirty_expire_interval
,
921 .maxlen
= sizeof(dirty_expire_interval
),
923 .proc_handler
= &proc_dointvec_userhz_jiffies
,
926 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
927 .procname
= "nr_pdflush_threads",
928 .data
= &nr_pdflush_threads
,
929 .maxlen
= sizeof nr_pdflush_threads
,
930 .mode
= 0444 /* read-only*/,
931 .proc_handler
= &proc_dointvec
,
934 .ctl_name
= VM_SWAPPINESS
,
935 .procname
= "swappiness",
936 .data
= &vm_swappiness
,
937 .maxlen
= sizeof(vm_swappiness
),
939 .proc_handler
= &proc_dointvec_minmax
,
940 .strategy
= &sysctl_intvec
,
942 .extra2
= &one_hundred
,
944 #ifdef CONFIG_HUGETLB_PAGE
946 .procname
= "nr_hugepages",
947 .data
= &max_huge_pages
,
948 .maxlen
= sizeof(unsigned long),
950 .proc_handler
= &hugetlb_sysctl_handler
,
951 .extra1
= (void *)&hugetlb_zero
,
952 .extra2
= (void *)&hugetlb_infinity
,
955 .ctl_name
= VM_HUGETLB_GROUP
,
956 .procname
= "hugetlb_shm_group",
957 .data
= &sysctl_hugetlb_shm_group
,
958 .maxlen
= sizeof(gid_t
),
960 .proc_handler
= &proc_dointvec
,
963 .ctl_name
= CTL_UNNUMBERED
,
964 .procname
= "hugepages_treat_as_movable",
965 .data
= &hugepages_treat_as_movable
,
966 .maxlen
= sizeof(int),
968 .proc_handler
= &hugetlb_treat_movable_handler
,
971 .ctl_name
= CTL_UNNUMBERED
,
972 .procname
= "nr_overcommit_hugepages",
973 .data
= &nr_overcommit_huge_pages
,
974 .maxlen
= sizeof(nr_overcommit_huge_pages
),
976 .proc_handler
= &proc_doulongvec_minmax
,
980 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
981 .procname
= "lowmem_reserve_ratio",
982 .data
= &sysctl_lowmem_reserve_ratio
,
983 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
985 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
986 .strategy
= &sysctl_intvec
,
989 .ctl_name
= VM_DROP_PAGECACHE
,
990 .procname
= "drop_caches",
991 .data
= &sysctl_drop_caches
,
992 .maxlen
= sizeof(int),
994 .proc_handler
= drop_caches_sysctl_handler
,
995 .strategy
= &sysctl_intvec
,
998 .ctl_name
= VM_MIN_FREE_KBYTES
,
999 .procname
= "min_free_kbytes",
1000 .data
= &min_free_kbytes
,
1001 .maxlen
= sizeof(min_free_kbytes
),
1003 .proc_handler
= &min_free_kbytes_sysctl_handler
,
1004 .strategy
= &sysctl_intvec
,
1008 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
1009 .procname
= "percpu_pagelist_fraction",
1010 .data
= &percpu_pagelist_fraction
,
1011 .maxlen
= sizeof(percpu_pagelist_fraction
),
1013 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
1014 .strategy
= &sysctl_intvec
,
1015 .extra1
= &min_percpu_pagelist_fract
,
1019 .ctl_name
= VM_MAX_MAP_COUNT
,
1020 .procname
= "max_map_count",
1021 .data
= &sysctl_max_map_count
,
1022 .maxlen
= sizeof(sysctl_max_map_count
),
1024 .proc_handler
= &proc_dointvec
1028 .ctl_name
= VM_LAPTOP_MODE
,
1029 .procname
= "laptop_mode",
1030 .data
= &laptop_mode
,
1031 .maxlen
= sizeof(laptop_mode
),
1033 .proc_handler
= &proc_dointvec_jiffies
,
1034 .strategy
= &sysctl_jiffies
,
1037 .ctl_name
= VM_BLOCK_DUMP
,
1038 .procname
= "block_dump",
1039 .data
= &block_dump
,
1040 .maxlen
= sizeof(block_dump
),
1042 .proc_handler
= &proc_dointvec
,
1043 .strategy
= &sysctl_intvec
,
1047 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
1048 .procname
= "vfs_cache_pressure",
1049 .data
= &sysctl_vfs_cache_pressure
,
1050 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
1052 .proc_handler
= &proc_dointvec
,
1053 .strategy
= &sysctl_intvec
,
1056 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1058 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
1059 .procname
= "legacy_va_layout",
1060 .data
= &sysctl_legacy_va_layout
,
1061 .maxlen
= sizeof(sysctl_legacy_va_layout
),
1063 .proc_handler
= &proc_dointvec
,
1064 .strategy
= &sysctl_intvec
,
1070 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
1071 .procname
= "zone_reclaim_mode",
1072 .data
= &zone_reclaim_mode
,
1073 .maxlen
= sizeof(zone_reclaim_mode
),
1075 .proc_handler
= &proc_dointvec
,
1076 .strategy
= &sysctl_intvec
,
1080 .ctl_name
= VM_MIN_UNMAPPED
,
1081 .procname
= "min_unmapped_ratio",
1082 .data
= &sysctl_min_unmapped_ratio
,
1083 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1085 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
1086 .strategy
= &sysctl_intvec
,
1088 .extra2
= &one_hundred
,
1091 .ctl_name
= VM_MIN_SLAB
,
1092 .procname
= "min_slab_ratio",
1093 .data
= &sysctl_min_slab_ratio
,
1094 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1096 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1097 .strategy
= &sysctl_intvec
,
1099 .extra2
= &one_hundred
,
1104 .ctl_name
= CTL_UNNUMBERED
,
1105 .procname
= "stat_interval",
1106 .data
= &sysctl_stat_interval
,
1107 .maxlen
= sizeof(sysctl_stat_interval
),
1109 .proc_handler
= &proc_dointvec_jiffies
,
1110 .strategy
= &sysctl_jiffies
,
1113 #ifdef CONFIG_SECURITY
1115 .ctl_name
= CTL_UNNUMBERED
,
1116 .procname
= "mmap_min_addr",
1117 .data
= &mmap_min_addr
,
1118 .maxlen
= sizeof(unsigned long),
1120 .proc_handler
= &proc_doulongvec_minmax
,
1125 .ctl_name
= CTL_UNNUMBERED
,
1126 .procname
= "numa_zonelist_order",
1127 .data
= &numa_zonelist_order
,
1128 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1130 .proc_handler
= &numa_zonelist_order_handler
,
1131 .strategy
= &sysctl_string
,
1134 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1135 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1137 .ctl_name
= VM_VDSO_ENABLED
,
1138 .procname
= "vdso_enabled",
1139 .data
= &vdso_enabled
,
1140 .maxlen
= sizeof(vdso_enabled
),
1142 .proc_handler
= &proc_dointvec
,
1143 .strategy
= &sysctl_intvec
,
1147 #ifdef CONFIG_HIGHMEM
1149 .ctl_name
= CTL_UNNUMBERED
,
1150 .procname
= "highmem_is_dirtyable",
1151 .data
= &vm_highmem_is_dirtyable
,
1152 .maxlen
= sizeof(vm_highmem_is_dirtyable
),
1154 .proc_handler
= &proc_dointvec_minmax
,
1155 .strategy
= &sysctl_intvec
,
1161 * NOTE: do not add new entries to this table unless you have read
1162 * Documentation/sysctl/ctl_unnumbered.txt
1167 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1168 static struct ctl_table binfmt_misc_table
[] = {
1173 static struct ctl_table fs_table
[] = {
1175 .ctl_name
= FS_NRINODE
,
1176 .procname
= "inode-nr",
1177 .data
= &inodes_stat
,
1178 .maxlen
= 2*sizeof(int),
1180 .proc_handler
= &proc_dointvec
,
1183 .ctl_name
= FS_STATINODE
,
1184 .procname
= "inode-state",
1185 .data
= &inodes_stat
,
1186 .maxlen
= 7*sizeof(int),
1188 .proc_handler
= &proc_dointvec
,
1191 .procname
= "file-nr",
1192 .data
= &files_stat
,
1193 .maxlen
= 3*sizeof(int),
1195 .proc_handler
= &proc_nr_files
,
1198 .ctl_name
= FS_MAXFILE
,
1199 .procname
= "file-max",
1200 .data
= &files_stat
.max_files
,
1201 .maxlen
= sizeof(int),
1203 .proc_handler
= &proc_dointvec
,
1206 .ctl_name
= CTL_UNNUMBERED
,
1207 .procname
= "nr_open",
1208 .data
= &sysctl_nr_open
,
1209 .maxlen
= sizeof(int),
1211 .proc_handler
= &proc_dointvec
,
1214 .ctl_name
= FS_DENTRY
,
1215 .procname
= "dentry-state",
1216 .data
= &dentry_stat
,
1217 .maxlen
= 6*sizeof(int),
1219 .proc_handler
= &proc_dointvec
,
1222 .ctl_name
= FS_OVERFLOWUID
,
1223 .procname
= "overflowuid",
1224 .data
= &fs_overflowuid
,
1225 .maxlen
= sizeof(int),
1227 .proc_handler
= &proc_dointvec_minmax
,
1228 .strategy
= &sysctl_intvec
,
1229 .extra1
= &minolduid
,
1230 .extra2
= &maxolduid
,
1233 .ctl_name
= FS_OVERFLOWGID
,
1234 .procname
= "overflowgid",
1235 .data
= &fs_overflowgid
,
1236 .maxlen
= sizeof(int),
1238 .proc_handler
= &proc_dointvec_minmax
,
1239 .strategy
= &sysctl_intvec
,
1240 .extra1
= &minolduid
,
1241 .extra2
= &maxolduid
,
1244 .ctl_name
= FS_LEASES
,
1245 .procname
= "leases-enable",
1246 .data
= &leases_enable
,
1247 .maxlen
= sizeof(int),
1249 .proc_handler
= &proc_dointvec
,
1251 #ifdef CONFIG_DNOTIFY
1253 .ctl_name
= FS_DIR_NOTIFY
,
1254 .procname
= "dir-notify-enable",
1255 .data
= &dir_notify_enable
,
1256 .maxlen
= sizeof(int),
1258 .proc_handler
= &proc_dointvec
,
1263 .ctl_name
= FS_LEASE_TIME
,
1264 .procname
= "lease-break-time",
1265 .data
= &lease_break_time
,
1266 .maxlen
= sizeof(int),
1268 .proc_handler
= &proc_dointvec_minmax
,
1269 .strategy
= &sysctl_intvec
,
1274 .procname
= "aio-nr",
1276 .maxlen
= sizeof(aio_nr
),
1278 .proc_handler
= &proc_doulongvec_minmax
,
1281 .procname
= "aio-max-nr",
1282 .data
= &aio_max_nr
,
1283 .maxlen
= sizeof(aio_max_nr
),
1285 .proc_handler
= &proc_doulongvec_minmax
,
1287 #ifdef CONFIG_INOTIFY_USER
1289 .ctl_name
= FS_INOTIFY
,
1290 .procname
= "inotify",
1292 .child
= inotify_table
,
1297 .ctl_name
= KERN_SETUID_DUMPABLE
,
1298 .procname
= "suid_dumpable",
1299 .data
= &suid_dumpable
,
1300 .maxlen
= sizeof(int),
1302 .proc_handler
= &proc_dointvec
,
1304 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1306 .ctl_name
= CTL_UNNUMBERED
,
1307 .procname
= "binfmt_misc",
1309 .child
= binfmt_misc_table
,
1313 * NOTE: do not add new entries to this table unless you have read
1314 * Documentation/sysctl/ctl_unnumbered.txt
1319 static struct ctl_table debug_table
[] = {
1320 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1322 .ctl_name
= CTL_UNNUMBERED
,
1323 .procname
= "exception-trace",
1324 .data
= &show_unhandled_signals
,
1325 .maxlen
= sizeof(int),
1327 .proc_handler
= proc_dointvec
1333 static struct ctl_table dev_table
[] = {
1337 static DEFINE_SPINLOCK(sysctl_lock
);
1339 /* called under sysctl_lock */
1340 static int use_table(struct ctl_table_header
*p
)
1342 if (unlikely(p
->unregistering
))
1348 /* called under sysctl_lock */
1349 static void unuse_table(struct ctl_table_header
*p
)
1352 if (unlikely(p
->unregistering
))
1353 complete(p
->unregistering
);
1356 /* called under sysctl_lock, will reacquire if has to wait */
1357 static void start_unregistering(struct ctl_table_header
*p
)
1360 * if p->used is 0, nobody will ever touch that entry again;
1361 * we'll eliminate all paths to it before dropping sysctl_lock
1363 if (unlikely(p
->used
)) {
1364 struct completion wait
;
1365 init_completion(&wait
);
1366 p
->unregistering
= &wait
;
1367 spin_unlock(&sysctl_lock
);
1368 wait_for_completion(&wait
);
1369 spin_lock(&sysctl_lock
);
1372 * do not remove from the list until nobody holds it; walking the
1373 * list in do_sysctl() relies on that.
1375 list_del_init(&p
->ctl_entry
);
1378 void sysctl_head_finish(struct ctl_table_header
*head
)
1382 spin_lock(&sysctl_lock
);
1384 spin_unlock(&sysctl_lock
);
1387 static struct list_head
*
1388 lookup_header_list(struct ctl_table_root
*root
, struct nsproxy
*namespaces
)
1390 struct list_head
*header_list
;
1391 header_list
= &root
->header_list
;
1393 header_list
= root
->lookup(root
, namespaces
);
1397 struct ctl_table_header
*__sysctl_head_next(struct nsproxy
*namespaces
,
1398 struct ctl_table_header
*prev
)
1400 struct ctl_table_root
*root
;
1401 struct list_head
*header_list
;
1402 struct ctl_table_header
*head
;
1403 struct list_head
*tmp
;
1405 spin_lock(&sysctl_lock
);
1408 tmp
= &prev
->ctl_entry
;
1412 tmp
= &root_table_header
.ctl_entry
;
1414 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1416 if (!use_table(head
))
1418 spin_unlock(&sysctl_lock
);
1423 header_list
= lookup_header_list(root
, namespaces
);
1424 if (tmp
!= header_list
)
1428 root
= list_entry(root
->root_list
.next
,
1429 struct ctl_table_root
, root_list
);
1430 if (root
== &sysctl_table_root
)
1432 header_list
= lookup_header_list(root
, namespaces
);
1433 } while (list_empty(header_list
));
1434 tmp
= header_list
->next
;
1437 spin_unlock(&sysctl_lock
);
1441 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1443 return __sysctl_head_next(current
->nsproxy
, prev
);
1446 void register_sysctl_root(struct ctl_table_root
*root
)
1448 spin_lock(&sysctl_lock
);
1449 list_add_tail(&root
->root_list
, &sysctl_table_root
.root_list
);
1450 spin_unlock(&sysctl_lock
);
1453 #ifdef CONFIG_SYSCTL_SYSCALL
1454 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1455 void __user
*newval
, size_t newlen
)
1457 struct ctl_table_header
*head
;
1458 int error
= -ENOTDIR
;
1460 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1464 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1468 for (head
= sysctl_head_next(NULL
); head
;
1469 head
= sysctl_head_next(head
)) {
1470 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1471 newval
, newlen
, head
->ctl_table
);
1472 if (error
!= -ENOTDIR
) {
1473 sysctl_head_finish(head
);
1480 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1482 struct __sysctl_args tmp
;
1485 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1488 error
= deprecated_sysctl_warning(&tmp
);
1493 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1494 tmp
.newval
, tmp
.newlen
);
1499 #endif /* CONFIG_SYSCTL_SYSCALL */
1502 * sysctl_perm does NOT grant the superuser all rights automatically, because
1503 * some sysctl variables are readonly even to root.
1506 static int test_perm(int mode
, int op
)
1510 else if (in_egroup_p(0))
1512 if ((mode
& op
& 0007) == op
)
1517 int sysctl_perm(struct ctl_table
*table
, int op
)
1520 error
= security_sysctl(table
, op
);
1523 return test_perm(table
->mode
, op
);
1526 #ifdef CONFIG_SYSCTL_SYSCALL
1527 static int parse_table(int __user
*name
, int nlen
,
1528 void __user
*oldval
, size_t __user
*oldlenp
,
1529 void __user
*newval
, size_t newlen
,
1530 struct ctl_table
*table
)
1536 if (get_user(n
, name
))
1538 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1539 if (!table
->ctl_name
)
1541 if (n
== table
->ctl_name
) {
1544 if (sysctl_perm(table
, 001))
1548 table
= table
->child
;
1551 error
= do_sysctl_strategy(table
, name
, nlen
,
1560 /* Perform the actual read/write of a sysctl table entry. */
1561 int do_sysctl_strategy (struct ctl_table
*table
,
1562 int __user
*name
, int nlen
,
1563 void __user
*oldval
, size_t __user
*oldlenp
,
1564 void __user
*newval
, size_t newlen
)
1572 if (sysctl_perm(table
, op
))
1575 if (table
->strategy
) {
1576 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1584 /* If there is no strategy routine, or if the strategy returns
1585 * zero, proceed with automatic r/w */
1586 if (table
->data
&& table
->maxlen
) {
1587 rc
= sysctl_data(table
, name
, nlen
, oldval
, oldlenp
,
1594 #endif /* CONFIG_SYSCTL_SYSCALL */
1596 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1598 for (; table
->ctl_name
|| table
->procname
; table
++) {
1599 table
->parent
= parent
;
1601 sysctl_set_parent(table
, table
->child
);
1605 static __init
int sysctl_init(void)
1608 sysctl_set_parent(NULL
, root_table
);
1609 err
= sysctl_check_table(current
->nsproxy
, root_table
);
1613 core_initcall(sysctl_init
);
1616 * __register_sysctl_paths - register a sysctl hierarchy
1617 * @root: List of sysctl headers to register on
1618 * @namespaces: Data to compute which lists of sysctl entries are visible
1619 * @path: The path to the directory the sysctl table is in.
1620 * @table: the top-level table structure
1622 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1623 * array. A completely 0 filled entry terminates the table.
1625 * The members of the &struct ctl_table structure are used as follows:
1627 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1628 * must be unique within that level of sysctl
1630 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1631 * enter a sysctl file
1633 * data - a pointer to data for use by proc_handler
1635 * maxlen - the maximum size in bytes of the data
1637 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1639 * child - a pointer to the child sysctl table if this entry is a directory, or
1642 * proc_handler - the text handler routine (described below)
1644 * strategy - the strategy routine (described below)
1646 * de - for internal use by the sysctl routines
1648 * extra1, extra2 - extra pointers usable by the proc handler routines
1650 * Leaf nodes in the sysctl tree will be represented by a single file
1651 * under /proc; non-leaf nodes will be represented by directories.
1653 * sysctl(2) can automatically manage read and write requests through
1654 * the sysctl table. The data and maxlen fields of the ctl_table
1655 * struct enable minimal validation of the values being written to be
1656 * performed, and the mode field allows minimal authentication.
1658 * More sophisticated management can be enabled by the provision of a
1659 * strategy routine with the table entry. This will be called before
1660 * any automatic read or write of the data is performed.
1662 * The strategy routine may return
1664 * < 0 - Error occurred (error is passed to user process)
1666 * 0 - OK - proceed with automatic read or write.
1668 * > 0 - OK - read or write has been done by the strategy routine, so
1669 * return immediately.
1671 * There must be a proc_handler routine for any terminal nodes
1672 * mirrored under /proc/sys (non-terminals are handled by a built-in
1673 * directory handler). Several default handlers are available to
1674 * cover common cases -
1676 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1677 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1678 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1680 * It is the handler's job to read the input buffer from user memory
1681 * and process it. The handler should return 0 on success.
1683 * This routine returns %NULL on a failure to register, and a pointer
1684 * to the table header on success.
1686 struct ctl_table_header
*__register_sysctl_paths(
1687 struct ctl_table_root
*root
,
1688 struct nsproxy
*namespaces
,
1689 const struct ctl_path
*path
, struct ctl_table
*table
)
1691 struct list_head
*header_list
;
1692 struct ctl_table_header
*header
;
1693 struct ctl_table
*new, **prevp
;
1694 unsigned int n
, npath
;
1696 /* Count the path components */
1697 for (npath
= 0; path
[npath
].ctl_name
|| path
[npath
].procname
; ++npath
)
1701 * For each path component, allocate a 2-element ctl_table array.
1702 * The first array element will be filled with the sysctl entry
1703 * for this, the second will be the sentinel (ctl_name == 0).
1705 * We allocate everything in one go so that we don't have to
1706 * worry about freeing additional memory in unregister_sysctl_table.
1708 header
= kzalloc(sizeof(struct ctl_table_header
) +
1709 (2 * npath
* sizeof(struct ctl_table
)), GFP_KERNEL
);
1713 new = (struct ctl_table
*) (header
+ 1);
1715 /* Now connect the dots */
1716 prevp
= &header
->ctl_table
;
1717 for (n
= 0; n
< npath
; ++n
, ++path
) {
1718 /* Copy the procname */
1719 new->procname
= path
->procname
;
1720 new->ctl_name
= path
->ctl_name
;
1724 prevp
= &new->child
;
1729 header
->ctl_table_arg
= table
;
1731 INIT_LIST_HEAD(&header
->ctl_entry
);
1733 header
->unregistering
= NULL
;
1734 header
->root
= root
;
1735 sysctl_set_parent(NULL
, header
->ctl_table
);
1736 if (sysctl_check_table(namespaces
, header
->ctl_table
)) {
1740 spin_lock(&sysctl_lock
);
1741 header_list
= lookup_header_list(root
, namespaces
);
1742 list_add_tail(&header
->ctl_entry
, header_list
);
1743 spin_unlock(&sysctl_lock
);
1749 * register_sysctl_table_path - register a sysctl table hierarchy
1750 * @path: The path to the directory the sysctl table is in.
1751 * @table: the top-level table structure
1753 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1754 * array. A completely 0 filled entry terminates the table.
1756 * See __register_sysctl_paths for more details.
1758 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
1759 struct ctl_table
*table
)
1761 return __register_sysctl_paths(&sysctl_table_root
, current
->nsproxy
,
1766 * register_sysctl_table - register a sysctl table hierarchy
1767 * @table: the top-level table structure
1769 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1770 * array. A completely 0 filled entry terminates the table.
1772 * See register_sysctl_paths for more details.
1774 struct ctl_table_header
*register_sysctl_table(struct ctl_table
*table
)
1776 static const struct ctl_path null_path
[] = { {} };
1778 return register_sysctl_paths(null_path
, table
);
1782 * unregister_sysctl_table - unregister a sysctl table hierarchy
1783 * @header: the header returned from register_sysctl_table
1785 * Unregisters the sysctl table and all children. proc entries may not
1786 * actually be removed until they are no longer used by anyone.
1788 void unregister_sysctl_table(struct ctl_table_header
* header
)
1795 spin_lock(&sysctl_lock
);
1796 start_unregistering(header
);
1797 spin_unlock(&sysctl_lock
);
1801 #else /* !CONFIG_SYSCTL */
1802 struct ctl_table_header
*register_sysctl_table(struct ctl_table
* table
)
1807 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
1808 struct ctl_table
*table
)
1813 void unregister_sysctl_table(struct ctl_table_header
* table
)
1817 #endif /* CONFIG_SYSCTL */
1823 #ifdef CONFIG_PROC_SYSCTL
1825 static int _proc_do_string(void* data
, int maxlen
, int write
,
1826 struct file
*filp
, void __user
*buffer
,
1827 size_t *lenp
, loff_t
*ppos
)
1833 if (!data
|| !maxlen
|| !*lenp
) {
1841 while (len
< *lenp
) {
1842 if (get_user(c
, p
++))
1844 if (c
== 0 || c
== '\n')
1850 if(copy_from_user(data
, buffer
, len
))
1852 ((char *) data
)[len
] = 0;
1870 if(copy_to_user(buffer
, data
, len
))
1873 if(put_user('\n', ((char __user
*) buffer
) + len
))
1884 * proc_dostring - read a string sysctl
1885 * @table: the sysctl table
1886 * @write: %TRUE if this is a write to the sysctl file
1887 * @filp: the file structure
1888 * @buffer: the user buffer
1889 * @lenp: the size of the user buffer
1890 * @ppos: file position
1892 * Reads/writes a string from/to the user buffer. If the kernel
1893 * buffer provided is not large enough to hold the string, the
1894 * string is truncated. The copied string is %NULL-terminated.
1895 * If the string is being read by the user process, it is copied
1896 * and a newline '\n' is added. It is truncated if the buffer is
1899 * Returns 0 on success.
1901 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
1902 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1904 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1905 buffer
, lenp
, ppos
);
1909 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1911 int write
, void *data
)
1914 *valp
= *negp
? -*lvalp
: *lvalp
;
1919 *lvalp
= (unsigned long)-val
;
1922 *lvalp
= (unsigned long)val
;
1928 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
1929 int write
, struct file
*filp
, void __user
*buffer
,
1930 size_t *lenp
, loff_t
*ppos
,
1931 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1932 int write
, void *data
),
1935 #define TMPBUFLEN 21
1936 int *i
, vleft
, first
=1, neg
, val
;
1940 char buf
[TMPBUFLEN
], *p
;
1941 char __user
*s
= buffer
;
1943 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1944 (*ppos
&& !write
)) {
1949 i
= (int *) tbl_data
;
1950 vleft
= table
->maxlen
/ sizeof(*i
);
1954 conv
= do_proc_dointvec_conv
;
1956 for (; left
&& vleft
--; i
++, first
=0) {
1971 if (len
> sizeof(buf
) - 1)
1972 len
= sizeof(buf
) - 1;
1973 if (copy_from_user(buf
, s
, len
))
1977 if (*p
== '-' && left
> 1) {
1981 if (*p
< '0' || *p
> '9')
1984 lval
= simple_strtoul(p
, &p
, 0);
1987 if ((len
< left
) && *p
&& !isspace(*p
))
1994 if (conv(&neg
, &lval
, i
, 1, data
))
2001 if (conv(&neg
, &lval
, i
, 0, data
))
2004 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
2008 if(copy_to_user(s
, buf
, len
))
2015 if (!write
&& !first
&& left
) {
2016 if(put_user('\n', s
))
2023 if (get_user(c
, s
++))
2038 static int do_proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2039 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
2040 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
2041 int write
, void *data
),
2044 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
2045 buffer
, lenp
, ppos
, conv
, data
);
2049 * proc_dointvec - read a vector of integers
2050 * @table: the sysctl table
2051 * @write: %TRUE if this is a write to the sysctl file
2052 * @filp: the file structure
2053 * @buffer: the user buffer
2054 * @lenp: the size of the user buffer
2055 * @ppos: file position
2057 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2058 * values from/to the user buffer, treated as an ASCII string.
2060 * Returns 0 on success.
2062 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2063 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2065 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2073 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
2075 int write
, void *data
)
2077 int op
= *(int *)data
;
2079 int val
= *negp
? -*lvalp
: *lvalp
;
2081 case OP_SET
: *valp
= val
; break;
2082 case OP_AND
: *valp
&= val
; break;
2083 case OP_OR
: *valp
|= val
; break;
2089 *lvalp
= (unsigned long)-val
;
2092 *lvalp
= (unsigned long)val
;
2099 * Taint values can only be increased
2101 static int proc_dointvec_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
2102 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2106 if (write
&& !capable(CAP_SYS_ADMIN
))
2110 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2111 do_proc_dointvec_bset_conv
,&op
);
2114 struct do_proc_dointvec_minmax_conv_param
{
2119 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
2121 int write
, void *data
)
2123 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
2125 int val
= *negp
? -*lvalp
: *lvalp
;
2126 if ((param
->min
&& *param
->min
> val
) ||
2127 (param
->max
&& *param
->max
< val
))
2134 *lvalp
= (unsigned long)-val
;
2137 *lvalp
= (unsigned long)val
;
2144 * proc_dointvec_minmax - read a vector of integers with min/max values
2145 * @table: the sysctl table
2146 * @write: %TRUE if this is a write to the sysctl file
2147 * @filp: the file structure
2148 * @buffer: the user buffer
2149 * @lenp: the size of the user buffer
2150 * @ppos: file position
2152 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2153 * values from/to the user buffer, treated as an ASCII string.
2155 * This routine will ensure the values are within the range specified by
2156 * table->extra1 (min) and table->extra2 (max).
2158 * Returns 0 on success.
2160 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2161 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2163 struct do_proc_dointvec_minmax_conv_param param
= {
2164 .min
= (int *) table
->extra1
,
2165 .max
= (int *) table
->extra2
,
2167 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2168 do_proc_dointvec_minmax_conv
, ¶m
);
2171 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
2173 void __user
*buffer
,
2174 size_t *lenp
, loff_t
*ppos
,
2175 unsigned long convmul
,
2176 unsigned long convdiv
)
2178 #define TMPBUFLEN 21
2179 unsigned long *i
, *min
, *max
, val
;
2180 int vleft
, first
=1, neg
;
2182 char buf
[TMPBUFLEN
], *p
;
2183 char __user
*s
= buffer
;
2185 if (!data
|| !table
->maxlen
|| !*lenp
||
2186 (*ppos
&& !write
)) {
2191 i
= (unsigned long *) data
;
2192 min
= (unsigned long *) table
->extra1
;
2193 max
= (unsigned long *) table
->extra2
;
2194 vleft
= table
->maxlen
/ sizeof(unsigned long);
2197 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
2212 if (len
> TMPBUFLEN
-1)
2214 if (copy_from_user(buf
, s
, len
))
2218 if (*p
== '-' && left
> 1) {
2222 if (*p
< '0' || *p
> '9')
2224 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2226 if ((len
< left
) && *p
&& !isspace(*p
))
2235 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2242 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2246 if(copy_to_user(s
, buf
, len
))
2253 if (!write
&& !first
&& left
) {
2254 if(put_user('\n', s
))
2261 if (get_user(c
, s
++))
2276 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2278 void __user
*buffer
,
2279 size_t *lenp
, loff_t
*ppos
,
2280 unsigned long convmul
,
2281 unsigned long convdiv
)
2283 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2284 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2288 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2289 * @table: the sysctl table
2290 * @write: %TRUE if this is a write to the sysctl file
2291 * @filp: the file structure
2292 * @buffer: the user buffer
2293 * @lenp: the size of the user buffer
2294 * @ppos: file position
2296 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2297 * values from/to the user buffer, treated as an ASCII string.
2299 * This routine will ensure the values are within the range specified by
2300 * table->extra1 (min) and table->extra2 (max).
2302 * Returns 0 on success.
2304 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2305 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2307 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2311 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2312 * @table: the sysctl table
2313 * @write: %TRUE if this is a write to the sysctl file
2314 * @filp: the file structure
2315 * @buffer: the user buffer
2316 * @lenp: the size of the user buffer
2317 * @ppos: file position
2319 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2320 * values from/to the user buffer, treated as an ASCII string. The values
2321 * are treated as milliseconds, and converted to jiffies when they are stored.
2323 * This routine will ensure the values are within the range specified by
2324 * table->extra1 (min) and table->extra2 (max).
2326 * Returns 0 on success.
2328 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2330 void __user
*buffer
,
2331 size_t *lenp
, loff_t
*ppos
)
2333 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2334 lenp
, ppos
, HZ
, 1000l);
2338 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2340 int write
, void *data
)
2343 if (*lvalp
> LONG_MAX
/ HZ
)
2345 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2351 lval
= (unsigned long)-val
;
2354 lval
= (unsigned long)val
;
2361 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2363 int write
, void *data
)
2366 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2368 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2374 lval
= (unsigned long)-val
;
2377 lval
= (unsigned long)val
;
2379 *lvalp
= jiffies_to_clock_t(lval
);
2384 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2386 int write
, void *data
)
2389 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2395 lval
= (unsigned long)-val
;
2398 lval
= (unsigned long)val
;
2400 *lvalp
= jiffies_to_msecs(lval
);
2406 * proc_dointvec_jiffies - read a vector of integers as seconds
2407 * @table: the sysctl table
2408 * @write: %TRUE if this is a write to the sysctl file
2409 * @filp: the file structure
2410 * @buffer: the user buffer
2411 * @lenp: the size of the user buffer
2412 * @ppos: file position
2414 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2415 * values from/to the user buffer, treated as an ASCII string.
2416 * The values read are assumed to be in seconds, and are converted into
2419 * Returns 0 on success.
2421 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2422 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2424 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2425 do_proc_dointvec_jiffies_conv
,NULL
);
2429 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2430 * @table: the sysctl table
2431 * @write: %TRUE if this is a write to the sysctl file
2432 * @filp: the file structure
2433 * @buffer: the user buffer
2434 * @lenp: the size of the user buffer
2435 * @ppos: pointer to the file position
2437 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2438 * values from/to the user buffer, treated as an ASCII string.
2439 * The values read are assumed to be in 1/USER_HZ seconds, and
2440 * are converted into jiffies.
2442 * Returns 0 on success.
2444 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2445 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2447 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2448 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2452 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2453 * @table: the sysctl table
2454 * @write: %TRUE if this is a write to the sysctl file
2455 * @filp: the file structure
2456 * @buffer: the user buffer
2457 * @lenp: the size of the user buffer
2458 * @ppos: file position
2459 * @ppos: the current position in the file
2461 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2462 * values from/to the user buffer, treated as an ASCII string.
2463 * The values read are assumed to be in 1/1000 seconds, and
2464 * are converted into jiffies.
2466 * Returns 0 on success.
2468 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2469 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2471 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2472 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2475 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
2476 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2478 struct pid
*new_pid
;
2482 tmp
= pid_nr_ns(cad_pid
, current
->nsproxy
->pid_ns
);
2484 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2485 lenp
, ppos
, NULL
, NULL
);
2489 new_pid
= find_get_pid(tmp
);
2493 put_pid(xchg(&cad_pid
, new_pid
));
2497 #else /* CONFIG_PROC_FS */
2499 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2500 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2505 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2506 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2511 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2512 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2517 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2518 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2523 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2524 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2529 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2530 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2535 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2536 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2541 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2543 void __user
*buffer
,
2544 size_t *lenp
, loff_t
*ppos
)
2550 #endif /* CONFIG_PROC_FS */
2553 #ifdef CONFIG_SYSCTL_SYSCALL
2555 * General sysctl support routines
2558 /* The generic sysctl data routine (used if no strategy routine supplied) */
2559 int sysctl_data(struct ctl_table
*table
, int __user
*name
, int nlen
,
2560 void __user
*oldval
, size_t __user
*oldlenp
,
2561 void __user
*newval
, size_t newlen
)
2565 /* Get out of I don't have a variable */
2566 if (!table
->data
|| !table
->maxlen
)
2569 if (oldval
&& oldlenp
) {
2570 if (get_user(len
, oldlenp
))
2573 if (len
> table
->maxlen
)
2574 len
= table
->maxlen
;
2575 if (copy_to_user(oldval
, table
->data
, len
))
2577 if (put_user(len
, oldlenp
))
2582 if (newval
&& newlen
) {
2583 if (newlen
> table
->maxlen
)
2584 newlen
= table
->maxlen
;
2586 if (copy_from_user(table
->data
, newval
, newlen
))
2592 /* The generic string strategy routine: */
2593 int sysctl_string(struct ctl_table
*table
, int __user
*name
, int nlen
,
2594 void __user
*oldval
, size_t __user
*oldlenp
,
2595 void __user
*newval
, size_t newlen
)
2597 if (!table
->data
|| !table
->maxlen
)
2600 if (oldval
&& oldlenp
) {
2602 if (get_user(bufsize
, oldlenp
))
2605 size_t len
= strlen(table
->data
), copied
;
2607 /* This shouldn't trigger for a well-formed sysctl */
2608 if (len
> table
->maxlen
)
2609 len
= table
->maxlen
;
2611 /* Copy up to a max of bufsize-1 bytes of the string */
2612 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2614 if (copy_to_user(oldval
, table
->data
, copied
) ||
2615 put_user(0, (char __user
*)(oldval
+ copied
)))
2617 if (put_user(len
, oldlenp
))
2621 if (newval
&& newlen
) {
2622 size_t len
= newlen
;
2623 if (len
> table
->maxlen
)
2624 len
= table
->maxlen
;
2625 if(copy_from_user(table
->data
, newval
, len
))
2627 if (len
== table
->maxlen
)
2629 ((char *) table
->data
)[len
] = 0;
2635 * This function makes sure that all of the integers in the vector
2636 * are between the minimum and maximum values given in the arrays
2637 * table->extra1 and table->extra2, respectively.
2639 int sysctl_intvec(struct ctl_table
*table
, int __user
*name
, int nlen
,
2640 void __user
*oldval
, size_t __user
*oldlenp
,
2641 void __user
*newval
, size_t newlen
)
2644 if (newval
&& newlen
) {
2645 int __user
*vec
= (int __user
*) newval
;
2646 int *min
= (int *) table
->extra1
;
2647 int *max
= (int *) table
->extra2
;
2651 if (newlen
% sizeof(int) != 0)
2654 if (!table
->extra1
&& !table
->extra2
)
2657 if (newlen
> table
->maxlen
)
2658 newlen
= table
->maxlen
;
2659 length
= newlen
/ sizeof(int);
2661 for (i
= 0; i
< length
; i
++) {
2663 if (get_user(value
, vec
+ i
))
2665 if (min
&& value
< min
[i
])
2667 if (max
&& value
> max
[i
])
2674 /* Strategy function to convert jiffies to seconds */
2675 int sysctl_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2676 void __user
*oldval
, size_t __user
*oldlenp
,
2677 void __user
*newval
, size_t newlen
)
2679 if (oldval
&& oldlenp
) {
2682 if (get_user(olen
, oldlenp
))
2687 if (olen
< sizeof(int))
2690 val
= *(int *)(table
->data
) / HZ
;
2691 if (put_user(val
, (int __user
*)oldval
))
2693 if (put_user(sizeof(int), oldlenp
))
2697 if (newval
&& newlen
) {
2699 if (newlen
!= sizeof(int))
2701 if (get_user(new, (int __user
*)newval
))
2703 *(int *)(table
->data
) = new*HZ
;
2708 /* Strategy function to convert jiffies to seconds */
2709 int sysctl_ms_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2710 void __user
*oldval
, size_t __user
*oldlenp
,
2711 void __user
*newval
, size_t newlen
)
2713 if (oldval
&& oldlenp
) {
2716 if (get_user(olen
, oldlenp
))
2721 if (olen
< sizeof(int))
2724 val
= jiffies_to_msecs(*(int *)(table
->data
));
2725 if (put_user(val
, (int __user
*)oldval
))
2727 if (put_user(sizeof(int), oldlenp
))
2731 if (newval
&& newlen
) {
2733 if (newlen
!= sizeof(int))
2735 if (get_user(new, (int __user
*)newval
))
2737 *(int *)(table
->data
) = msecs_to_jiffies(new);
2744 #else /* CONFIG_SYSCTL_SYSCALL */
2747 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2749 struct __sysctl_args tmp
;
2752 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2755 error
= deprecated_sysctl_warning(&tmp
);
2757 /* If no error reading the parameters then just -ENOSYS ... */
2764 int sysctl_data(struct ctl_table
*table
, int __user
*name
, int nlen
,
2765 void __user
*oldval
, size_t __user
*oldlenp
,
2766 void __user
*newval
, size_t newlen
)
2771 int sysctl_string(struct ctl_table
*table
, int __user
*name
, int nlen
,
2772 void __user
*oldval
, size_t __user
*oldlenp
,
2773 void __user
*newval
, size_t newlen
)
2778 int sysctl_intvec(struct ctl_table
*table
, int __user
*name
, int nlen
,
2779 void __user
*oldval
, size_t __user
*oldlenp
,
2780 void __user
*newval
, size_t newlen
)
2785 int sysctl_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2786 void __user
*oldval
, size_t __user
*oldlenp
,
2787 void __user
*newval
, size_t newlen
)
2792 int sysctl_ms_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2793 void __user
*oldval
, size_t __user
*oldlenp
,
2794 void __user
*newval
, size_t newlen
)
2799 #endif /* CONFIG_SYSCTL_SYSCALL */
2801 static int deprecated_sysctl_warning(struct __sysctl_args
*args
)
2803 static int msg_count
;
2804 int name
[CTL_MAXNAME
];
2807 /* Check args->nlen. */
2808 if (args
->nlen
< 0 || args
->nlen
> CTL_MAXNAME
)
2811 /* Read in the sysctl name for better debug message logging */
2812 for (i
= 0; i
< args
->nlen
; i
++)
2813 if (get_user(name
[i
], args
->name
+ i
))
2816 /* Ignore accesses to kernel.version */
2817 if ((args
->nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2820 if (msg_count
< 5) {
2823 "warning: process `%s' used the deprecated sysctl "
2824 "system call with ", current
->comm
);
2825 for (i
= 0; i
< args
->nlen
; i
++)
2826 printk("%d.", name
[i
]);
2833 * No sense putting this after each symbol definition, twice,
2834 * exception granted :-)
2836 EXPORT_SYMBOL(proc_dointvec
);
2837 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2838 EXPORT_SYMBOL(proc_dointvec_minmax
);
2839 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2840 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2841 EXPORT_SYMBOL(proc_dostring
);
2842 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2843 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2844 EXPORT_SYMBOL(register_sysctl_table
);
2845 EXPORT_SYMBOL(register_sysctl_paths
);
2846 EXPORT_SYMBOL(sysctl_intvec
);
2847 EXPORT_SYMBOL(sysctl_jiffies
);
2848 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2849 EXPORT_SYMBOL(sysctl_string
);
2850 EXPORT_SYMBOL(sysctl_data
);
2851 EXPORT_SYMBOL(unregister_sysctl_table
);