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
;
86 #ifdef CONFIG_RCU_TORTURE_TEST
87 extern int rcutorture_runnable
;
88 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
90 /* Constants used for minimum and maximum */
91 #if defined(CONFIG_DETECT_SOFTLOCKUP) || defined(CONFIG_HIGHMEM)
95 #ifdef CONFIG_DETECT_SOFTLOCKUP
96 static int sixty
= 60;
104 static int one_hundred
= 100;
106 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
107 static int maxolduid
= 65535;
108 static int minolduid
;
109 static int min_percpu_pagelist_fract
= 8;
111 static int ngroups_max
= NGROUPS_MAX
;
113 #ifdef CONFIG_MODULES
114 extern char modprobe_path
[];
116 #ifdef CONFIG_CHR_DEV_SG
117 extern int sg_big_buff
;
121 extern char reboot_command
[];
122 extern int stop_a_enabled
;
123 extern int scons_pwroff
;
127 extern int pwrsw_enabled
;
128 extern int unaligned_enabled
;
132 #ifdef CONFIG_MATHEMU
133 extern int sysctl_ieee_emulation_warnings
;
135 extern int sysctl_userprocess_debug
;
136 extern int spin_retry
;
139 #ifdef CONFIG_BSD_PROCESS_ACCT
140 extern int acct_parm
[];
144 extern int no_unaligned_warning
;
147 #ifdef CONFIG_RT_MUTEXES
148 extern int max_lock_depth
;
151 #ifdef CONFIG_PROC_SYSCTL
152 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
153 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
154 static int proc_dointvec_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
155 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
158 static struct ctl_table root_table
[];
159 static struct ctl_table_root sysctl_table_root
;
160 static struct ctl_table_header root_table_header
= {
161 .ctl_table
= root_table
,
162 .ctl_entry
= LIST_HEAD_INIT(sysctl_table_root
.header_list
),
163 .root
= &sysctl_table_root
,
165 static struct ctl_table_root sysctl_table_root
= {
166 .root_list
= LIST_HEAD_INIT(sysctl_table_root
.root_list
),
167 .header_list
= LIST_HEAD_INIT(root_table_header
.ctl_entry
),
170 static struct ctl_table kern_table
[];
171 static struct ctl_table vm_table
[];
172 static struct ctl_table fs_table
[];
173 static struct ctl_table debug_table
[];
174 static struct ctl_table dev_table
[];
175 extern struct ctl_table random_table
[];
176 #ifdef CONFIG_INOTIFY_USER
177 extern struct ctl_table inotify_table
[];
180 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
181 int sysctl_legacy_va_layout
;
184 extern int prove_locking
;
185 extern int lock_stat
;
187 /* The default sysctl tables: */
189 static struct ctl_table root_table
[] = {
191 .ctl_name
= CTL_KERN
,
192 .procname
= "kernel",
209 .ctl_name
= CTL_DEBUG
,
212 .child
= debug_table
,
221 * NOTE: do not add new entries to this table unless you have read
222 * Documentation/sysctl/ctl_unnumbered.txt
227 #ifdef CONFIG_SCHED_DEBUG
228 static int min_sched_granularity_ns
= 100000; /* 100 usecs */
229 static int max_sched_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
230 static int min_wakeup_granularity_ns
; /* 0 usecs */
231 static int max_wakeup_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
234 static struct ctl_table kern_table
[] = {
235 #ifdef CONFIG_SCHED_DEBUG
237 .ctl_name
= CTL_UNNUMBERED
,
238 .procname
= "sched_min_granularity_ns",
239 .data
= &sysctl_sched_min_granularity
,
240 .maxlen
= sizeof(unsigned int),
242 .proc_handler
= &sched_nr_latency_handler
,
243 .strategy
= &sysctl_intvec
,
244 .extra1
= &min_sched_granularity_ns
,
245 .extra2
= &max_sched_granularity_ns
,
248 .ctl_name
= CTL_UNNUMBERED
,
249 .procname
= "sched_latency_ns",
250 .data
= &sysctl_sched_latency
,
251 .maxlen
= sizeof(unsigned int),
253 .proc_handler
= &sched_nr_latency_handler
,
254 .strategy
= &sysctl_intvec
,
255 .extra1
= &min_sched_granularity_ns
,
256 .extra2
= &max_sched_granularity_ns
,
259 .ctl_name
= CTL_UNNUMBERED
,
260 .procname
= "sched_wakeup_granularity_ns",
261 .data
= &sysctl_sched_wakeup_granularity
,
262 .maxlen
= sizeof(unsigned int),
264 .proc_handler
= &proc_dointvec_minmax
,
265 .strategy
= &sysctl_intvec
,
266 .extra1
= &min_wakeup_granularity_ns
,
267 .extra2
= &max_wakeup_granularity_ns
,
270 .ctl_name
= CTL_UNNUMBERED
,
271 .procname
= "sched_shares_ratelimit",
272 .data
= &sysctl_sched_shares_ratelimit
,
273 .maxlen
= sizeof(unsigned int),
275 .proc_handler
= &proc_dointvec
,
278 .ctl_name
= CTL_UNNUMBERED
,
279 .procname
= "sched_child_runs_first",
280 .data
= &sysctl_sched_child_runs_first
,
281 .maxlen
= sizeof(unsigned int),
283 .proc_handler
= &proc_dointvec
,
286 .ctl_name
= CTL_UNNUMBERED
,
287 .procname
= "sched_features",
288 .data
= &sysctl_sched_features
,
289 .maxlen
= sizeof(unsigned int),
291 .proc_handler
= &proc_dointvec
,
294 .ctl_name
= CTL_UNNUMBERED
,
295 .procname
= "sched_migration_cost",
296 .data
= &sysctl_sched_migration_cost
,
297 .maxlen
= sizeof(unsigned int),
299 .proc_handler
= &proc_dointvec
,
302 .ctl_name
= CTL_UNNUMBERED
,
303 .procname
= "sched_nr_migrate",
304 .data
= &sysctl_sched_nr_migrate
,
305 .maxlen
= sizeof(unsigned int),
307 .proc_handler
= &proc_dointvec
,
311 .ctl_name
= CTL_UNNUMBERED
,
312 .procname
= "sched_rt_period_us",
313 .data
= &sysctl_sched_rt_period
,
314 .maxlen
= sizeof(unsigned int),
316 .proc_handler
= &sched_rt_handler
,
319 .ctl_name
= CTL_UNNUMBERED
,
320 .procname
= "sched_rt_runtime_us",
321 .data
= &sysctl_sched_rt_runtime
,
322 .maxlen
= sizeof(int),
324 .proc_handler
= &sched_rt_handler
,
327 .ctl_name
= CTL_UNNUMBERED
,
328 .procname
= "sched_compat_yield",
329 .data
= &sysctl_sched_compat_yield
,
330 .maxlen
= sizeof(unsigned int),
332 .proc_handler
= &proc_dointvec
,
334 #ifdef CONFIG_PROVE_LOCKING
336 .ctl_name
= CTL_UNNUMBERED
,
337 .procname
= "prove_locking",
338 .data
= &prove_locking
,
339 .maxlen
= sizeof(int),
341 .proc_handler
= &proc_dointvec
,
344 #ifdef CONFIG_LOCK_STAT
346 .ctl_name
= CTL_UNNUMBERED
,
347 .procname
= "lock_stat",
349 .maxlen
= sizeof(int),
351 .proc_handler
= &proc_dointvec
,
355 .ctl_name
= KERN_PANIC
,
357 .data
= &panic_timeout
,
358 .maxlen
= sizeof(int),
360 .proc_handler
= &proc_dointvec
,
363 .ctl_name
= KERN_CORE_USES_PID
,
364 .procname
= "core_uses_pid",
365 .data
= &core_uses_pid
,
366 .maxlen
= sizeof(int),
368 .proc_handler
= &proc_dointvec
,
371 .ctl_name
= KERN_CORE_PATTERN
,
372 .procname
= "core_pattern",
373 .data
= core_pattern
,
374 .maxlen
= CORENAME_MAX_SIZE
,
376 .proc_handler
= &proc_dostring
,
377 .strategy
= &sysctl_string
,
379 #ifdef CONFIG_PROC_SYSCTL
381 .procname
= "tainted",
383 .maxlen
= sizeof(int),
385 .proc_handler
= &proc_dointvec_taint
,
388 #ifdef CONFIG_LATENCYTOP
390 .procname
= "latencytop",
391 .data
= &latencytop_enabled
,
392 .maxlen
= sizeof(int),
394 .proc_handler
= &proc_dointvec
,
397 #ifdef CONFIG_BLK_DEV_INITRD
399 .ctl_name
= KERN_REALROOTDEV
,
400 .procname
= "real-root-dev",
401 .data
= &real_root_dev
,
402 .maxlen
= sizeof(int),
404 .proc_handler
= &proc_dointvec
,
408 .ctl_name
= CTL_UNNUMBERED
,
409 .procname
= "print-fatal-signals",
410 .data
= &print_fatal_signals
,
411 .maxlen
= sizeof(int),
413 .proc_handler
= &proc_dointvec
,
417 .ctl_name
= KERN_SPARC_REBOOT
,
418 .procname
= "reboot-cmd",
419 .data
= reboot_command
,
422 .proc_handler
= &proc_dostring
,
423 .strategy
= &sysctl_string
,
426 .ctl_name
= KERN_SPARC_STOP_A
,
427 .procname
= "stop-a",
428 .data
= &stop_a_enabled
,
429 .maxlen
= sizeof (int),
431 .proc_handler
= &proc_dointvec
,
434 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
435 .procname
= "scons-poweroff",
436 .data
= &scons_pwroff
,
437 .maxlen
= sizeof (int),
439 .proc_handler
= &proc_dointvec
,
444 .ctl_name
= KERN_HPPA_PWRSW
,
445 .procname
= "soft-power",
446 .data
= &pwrsw_enabled
,
447 .maxlen
= sizeof (int),
449 .proc_handler
= &proc_dointvec
,
452 .ctl_name
= KERN_HPPA_UNALIGNED
,
453 .procname
= "unaligned-trap",
454 .data
= &unaligned_enabled
,
455 .maxlen
= sizeof (int),
457 .proc_handler
= &proc_dointvec
,
461 .ctl_name
= KERN_CTLALTDEL
,
462 .procname
= "ctrl-alt-del",
464 .maxlen
= sizeof(int),
466 .proc_handler
= &proc_dointvec
,
470 .ctl_name
= CTL_UNNUMBERED
,
471 .procname
= "ftrace_enabled",
472 .data
= &ftrace_enabled
,
473 .maxlen
= sizeof(int),
475 .proc_handler
= &ftrace_enable_sysctl
,
478 #ifdef CONFIG_MODULES
480 .ctl_name
= KERN_MODPROBE
,
481 .procname
= "modprobe",
482 .data
= &modprobe_path
,
483 .maxlen
= KMOD_PATH_LEN
,
485 .proc_handler
= &proc_dostring
,
486 .strategy
= &sysctl_string
,
489 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
491 .ctl_name
= KERN_HOTPLUG
,
492 .procname
= "hotplug",
493 .data
= &uevent_helper
,
494 .maxlen
= UEVENT_HELPER_PATH_LEN
,
496 .proc_handler
= &proc_dostring
,
497 .strategy
= &sysctl_string
,
500 #ifdef CONFIG_CHR_DEV_SG
502 .ctl_name
= KERN_SG_BIG_BUFF
,
503 .procname
= "sg-big-buff",
504 .data
= &sg_big_buff
,
505 .maxlen
= sizeof (int),
507 .proc_handler
= &proc_dointvec
,
510 #ifdef CONFIG_BSD_PROCESS_ACCT
512 .ctl_name
= KERN_ACCT
,
515 .maxlen
= 3*sizeof(int),
517 .proc_handler
= &proc_dointvec
,
520 #ifdef CONFIG_MAGIC_SYSRQ
522 .ctl_name
= KERN_SYSRQ
,
524 .data
= &__sysrq_enabled
,
525 .maxlen
= sizeof (int),
527 .proc_handler
= &proc_dointvec
,
530 #ifdef CONFIG_PROC_SYSCTL
532 .procname
= "cad_pid",
534 .maxlen
= sizeof (int),
536 .proc_handler
= &proc_do_cad_pid
,
540 .ctl_name
= KERN_MAX_THREADS
,
541 .procname
= "threads-max",
542 .data
= &max_threads
,
543 .maxlen
= sizeof(int),
545 .proc_handler
= &proc_dointvec
,
548 .ctl_name
= KERN_RANDOM
,
549 .procname
= "random",
551 .child
= random_table
,
554 .ctl_name
= KERN_OVERFLOWUID
,
555 .procname
= "overflowuid",
556 .data
= &overflowuid
,
557 .maxlen
= sizeof(int),
559 .proc_handler
= &proc_dointvec_minmax
,
560 .strategy
= &sysctl_intvec
,
561 .extra1
= &minolduid
,
562 .extra2
= &maxolduid
,
565 .ctl_name
= KERN_OVERFLOWGID
,
566 .procname
= "overflowgid",
567 .data
= &overflowgid
,
568 .maxlen
= sizeof(int),
570 .proc_handler
= &proc_dointvec_minmax
,
571 .strategy
= &sysctl_intvec
,
572 .extra1
= &minolduid
,
573 .extra2
= &maxolduid
,
576 #ifdef CONFIG_MATHEMU
578 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
579 .procname
= "ieee_emulation_warnings",
580 .data
= &sysctl_ieee_emulation_warnings
,
581 .maxlen
= sizeof(int),
583 .proc_handler
= &proc_dointvec
,
587 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
588 .procname
= "userprocess_debug",
589 .data
= &sysctl_userprocess_debug
,
590 .maxlen
= sizeof(int),
592 .proc_handler
= &proc_dointvec
,
596 .ctl_name
= KERN_PIDMAX
,
597 .procname
= "pid_max",
599 .maxlen
= sizeof (int),
601 .proc_handler
= &proc_dointvec_minmax
,
602 .strategy
= sysctl_intvec
,
603 .extra1
= &pid_max_min
,
604 .extra2
= &pid_max_max
,
607 .ctl_name
= KERN_PANIC_ON_OOPS
,
608 .procname
= "panic_on_oops",
609 .data
= &panic_on_oops
,
610 .maxlen
= sizeof(int),
612 .proc_handler
= &proc_dointvec
,
614 #if defined CONFIG_PRINTK
616 .ctl_name
= KERN_PRINTK
,
617 .procname
= "printk",
618 .data
= &console_loglevel
,
619 .maxlen
= 4*sizeof(int),
621 .proc_handler
= &proc_dointvec
,
624 .ctl_name
= KERN_PRINTK_RATELIMIT
,
625 .procname
= "printk_ratelimit",
626 .data
= &printk_ratelimit_jiffies
,
627 .maxlen
= sizeof(int),
629 .proc_handler
= &proc_dointvec_jiffies
,
630 .strategy
= &sysctl_jiffies
,
633 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
634 .procname
= "printk_ratelimit_burst",
635 .data
= &printk_ratelimit_burst
,
636 .maxlen
= sizeof(int),
638 .proc_handler
= &proc_dointvec
,
642 .ctl_name
= KERN_NGROUPS_MAX
,
643 .procname
= "ngroups_max",
644 .data
= &ngroups_max
,
645 .maxlen
= sizeof (int),
647 .proc_handler
= &proc_dointvec
,
649 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
651 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
652 .procname
= "unknown_nmi_panic",
653 .data
= &unknown_nmi_panic
,
654 .maxlen
= sizeof (int),
656 .proc_handler
= &proc_dointvec
,
659 .procname
= "nmi_watchdog",
660 .data
= &nmi_watchdog_enabled
,
661 .maxlen
= sizeof (int),
663 .proc_handler
= &proc_nmi_enabled
,
666 #if defined(CONFIG_X86)
668 .ctl_name
= KERN_PANIC_ON_NMI
,
669 .procname
= "panic_on_unrecovered_nmi",
670 .data
= &panic_on_unrecovered_nmi
,
671 .maxlen
= sizeof(int),
673 .proc_handler
= &proc_dointvec
,
676 .ctl_name
= KERN_BOOTLOADER_TYPE
,
677 .procname
= "bootloader_type",
678 .data
= &bootloader_type
,
679 .maxlen
= sizeof (int),
681 .proc_handler
= &proc_dointvec
,
684 .ctl_name
= CTL_UNNUMBERED
,
685 .procname
= "kstack_depth_to_print",
686 .data
= &kstack_depth_to_print
,
687 .maxlen
= sizeof(int),
689 .proc_handler
= &proc_dointvec
,
692 .ctl_name
= CTL_UNNUMBERED
,
693 .procname
= "io_delay_type",
694 .data
= &io_delay_type
,
695 .maxlen
= sizeof(int),
697 .proc_handler
= &proc_dointvec
,
700 #if defined(CONFIG_MMU)
702 .ctl_name
= KERN_RANDOMIZE
,
703 .procname
= "randomize_va_space",
704 .data
= &randomize_va_space
,
705 .maxlen
= sizeof(int),
707 .proc_handler
= &proc_dointvec
,
710 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
712 .ctl_name
= KERN_SPIN_RETRY
,
713 .procname
= "spin_retry",
715 .maxlen
= sizeof (int),
717 .proc_handler
= &proc_dointvec
,
720 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
722 .procname
= "acpi_video_flags",
723 .data
= &acpi_realmode_flags
,
724 .maxlen
= sizeof (unsigned long),
726 .proc_handler
= &proc_doulongvec_minmax
,
731 .ctl_name
= KERN_IA64_UNALIGNED
,
732 .procname
= "ignore-unaligned-usertrap",
733 .data
= &no_unaligned_warning
,
734 .maxlen
= sizeof (int),
736 .proc_handler
= &proc_dointvec
,
739 #ifdef CONFIG_DETECT_SOFTLOCKUP
741 .ctl_name
= CTL_UNNUMBERED
,
742 .procname
= "softlockup_thresh",
743 .data
= &softlockup_thresh
,
744 .maxlen
= sizeof(unsigned long),
746 .proc_handler
= &proc_doulongvec_minmax
,
747 .strategy
= &sysctl_intvec
,
752 .ctl_name
= CTL_UNNUMBERED
,
753 .procname
= "hung_task_check_count",
754 .data
= &sysctl_hung_task_check_count
,
755 .maxlen
= sizeof(unsigned long),
757 .proc_handler
= &proc_doulongvec_minmax
,
758 .strategy
= &sysctl_intvec
,
761 .ctl_name
= CTL_UNNUMBERED
,
762 .procname
= "hung_task_timeout_secs",
763 .data
= &sysctl_hung_task_timeout_secs
,
764 .maxlen
= sizeof(unsigned long),
766 .proc_handler
= &proc_doulongvec_minmax
,
767 .strategy
= &sysctl_intvec
,
770 .ctl_name
= CTL_UNNUMBERED
,
771 .procname
= "hung_task_warnings",
772 .data
= &sysctl_hung_task_warnings
,
773 .maxlen
= sizeof(unsigned long),
775 .proc_handler
= &proc_doulongvec_minmax
,
776 .strategy
= &sysctl_intvec
,
781 .ctl_name
= KERN_COMPAT_LOG
,
782 .procname
= "compat-log",
784 .maxlen
= sizeof (int),
786 .proc_handler
= &proc_dointvec
,
789 #ifdef CONFIG_RT_MUTEXES
791 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
792 .procname
= "max_lock_depth",
793 .data
= &max_lock_depth
,
794 .maxlen
= sizeof(int),
796 .proc_handler
= &proc_dointvec
,
799 #ifdef CONFIG_PROC_FS
801 .ctl_name
= CTL_UNNUMBERED
,
802 .procname
= "maps_protect",
803 .data
= &maps_protect
,
804 .maxlen
= sizeof(int),
806 .proc_handler
= &proc_dointvec
,
810 .ctl_name
= CTL_UNNUMBERED
,
811 .procname
= "poweroff_cmd",
812 .data
= &poweroff_cmd
,
813 .maxlen
= POWEROFF_CMD_PATH_LEN
,
815 .proc_handler
= &proc_dostring
,
816 .strategy
= &sysctl_string
,
820 .ctl_name
= CTL_UNNUMBERED
,
823 .child
= key_sysctls
,
826 #ifdef CONFIG_RCU_TORTURE_TEST
828 .ctl_name
= CTL_UNNUMBERED
,
829 .procname
= "rcutorture_runnable",
830 .data
= &rcutorture_runnable
,
831 .maxlen
= sizeof(int),
833 .proc_handler
= &proc_dointvec
,
837 * NOTE: do not add new entries to this table unless you have read
838 * Documentation/sysctl/ctl_unnumbered.txt
843 static struct ctl_table vm_table
[] = {
845 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
846 .procname
= "overcommit_memory",
847 .data
= &sysctl_overcommit_memory
,
848 .maxlen
= sizeof(sysctl_overcommit_memory
),
850 .proc_handler
= &proc_dointvec
,
853 .ctl_name
= VM_PANIC_ON_OOM
,
854 .procname
= "panic_on_oom",
855 .data
= &sysctl_panic_on_oom
,
856 .maxlen
= sizeof(sysctl_panic_on_oom
),
858 .proc_handler
= &proc_dointvec
,
861 .ctl_name
= CTL_UNNUMBERED
,
862 .procname
= "oom_kill_allocating_task",
863 .data
= &sysctl_oom_kill_allocating_task
,
864 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
866 .proc_handler
= &proc_dointvec
,
869 .ctl_name
= CTL_UNNUMBERED
,
870 .procname
= "oom_dump_tasks",
871 .data
= &sysctl_oom_dump_tasks
,
872 .maxlen
= sizeof(sysctl_oom_dump_tasks
),
874 .proc_handler
= &proc_dointvec
,
877 .ctl_name
= VM_OVERCOMMIT_RATIO
,
878 .procname
= "overcommit_ratio",
879 .data
= &sysctl_overcommit_ratio
,
880 .maxlen
= sizeof(sysctl_overcommit_ratio
),
882 .proc_handler
= &proc_dointvec
,
885 .ctl_name
= VM_PAGE_CLUSTER
,
886 .procname
= "page-cluster",
887 .data
= &page_cluster
,
888 .maxlen
= sizeof(int),
890 .proc_handler
= &proc_dointvec
,
893 .ctl_name
= VM_DIRTY_BACKGROUND
,
894 .procname
= "dirty_background_ratio",
895 .data
= &dirty_background_ratio
,
896 .maxlen
= sizeof(dirty_background_ratio
),
898 .proc_handler
= &proc_dointvec_minmax
,
899 .strategy
= &sysctl_intvec
,
901 .extra2
= &one_hundred
,
904 .ctl_name
= VM_DIRTY_RATIO
,
905 .procname
= "dirty_ratio",
906 .data
= &vm_dirty_ratio
,
907 .maxlen
= sizeof(vm_dirty_ratio
),
909 .proc_handler
= &dirty_ratio_handler
,
910 .strategy
= &sysctl_intvec
,
912 .extra2
= &one_hundred
,
915 .procname
= "dirty_writeback_centisecs",
916 .data
= &dirty_writeback_interval
,
917 .maxlen
= sizeof(dirty_writeback_interval
),
919 .proc_handler
= &dirty_writeback_centisecs_handler
,
922 .procname
= "dirty_expire_centisecs",
923 .data
= &dirty_expire_interval
,
924 .maxlen
= sizeof(dirty_expire_interval
),
926 .proc_handler
= &proc_dointvec_userhz_jiffies
,
929 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
930 .procname
= "nr_pdflush_threads",
931 .data
= &nr_pdflush_threads
,
932 .maxlen
= sizeof nr_pdflush_threads
,
933 .mode
= 0444 /* read-only*/,
934 .proc_handler
= &proc_dointvec
,
937 .ctl_name
= VM_SWAPPINESS
,
938 .procname
= "swappiness",
939 .data
= &vm_swappiness
,
940 .maxlen
= sizeof(vm_swappiness
),
942 .proc_handler
= &proc_dointvec_minmax
,
943 .strategy
= &sysctl_intvec
,
945 .extra2
= &one_hundred
,
947 #ifdef CONFIG_HUGETLB_PAGE
949 .procname
= "nr_hugepages",
950 .data
= &max_huge_pages
,
951 .maxlen
= sizeof(unsigned long),
953 .proc_handler
= &hugetlb_sysctl_handler
,
954 .extra1
= (void *)&hugetlb_zero
,
955 .extra2
= (void *)&hugetlb_infinity
,
958 .ctl_name
= VM_HUGETLB_GROUP
,
959 .procname
= "hugetlb_shm_group",
960 .data
= &sysctl_hugetlb_shm_group
,
961 .maxlen
= sizeof(gid_t
),
963 .proc_handler
= &proc_dointvec
,
966 .ctl_name
= CTL_UNNUMBERED
,
967 .procname
= "hugepages_treat_as_movable",
968 .data
= &hugepages_treat_as_movable
,
969 .maxlen
= sizeof(int),
971 .proc_handler
= &hugetlb_treat_movable_handler
,
974 .ctl_name
= CTL_UNNUMBERED
,
975 .procname
= "nr_overcommit_hugepages",
976 .data
= &sysctl_overcommit_huge_pages
,
977 .maxlen
= sizeof(sysctl_overcommit_huge_pages
),
979 .proc_handler
= &hugetlb_overcommit_handler
,
983 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
984 .procname
= "lowmem_reserve_ratio",
985 .data
= &sysctl_lowmem_reserve_ratio
,
986 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
988 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
989 .strategy
= &sysctl_intvec
,
992 .ctl_name
= VM_DROP_PAGECACHE
,
993 .procname
= "drop_caches",
994 .data
= &sysctl_drop_caches
,
995 .maxlen
= sizeof(int),
997 .proc_handler
= drop_caches_sysctl_handler
,
998 .strategy
= &sysctl_intvec
,
1001 .ctl_name
= VM_MIN_FREE_KBYTES
,
1002 .procname
= "min_free_kbytes",
1003 .data
= &min_free_kbytes
,
1004 .maxlen
= sizeof(min_free_kbytes
),
1006 .proc_handler
= &min_free_kbytes_sysctl_handler
,
1007 .strategy
= &sysctl_intvec
,
1011 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
1012 .procname
= "percpu_pagelist_fraction",
1013 .data
= &percpu_pagelist_fraction
,
1014 .maxlen
= sizeof(percpu_pagelist_fraction
),
1016 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
1017 .strategy
= &sysctl_intvec
,
1018 .extra1
= &min_percpu_pagelist_fract
,
1022 .ctl_name
= VM_MAX_MAP_COUNT
,
1023 .procname
= "max_map_count",
1024 .data
= &sysctl_max_map_count
,
1025 .maxlen
= sizeof(sysctl_max_map_count
),
1027 .proc_handler
= &proc_dointvec
1031 .ctl_name
= VM_LAPTOP_MODE
,
1032 .procname
= "laptop_mode",
1033 .data
= &laptop_mode
,
1034 .maxlen
= sizeof(laptop_mode
),
1036 .proc_handler
= &proc_dointvec_jiffies
,
1037 .strategy
= &sysctl_jiffies
,
1040 .ctl_name
= VM_BLOCK_DUMP
,
1041 .procname
= "block_dump",
1042 .data
= &block_dump
,
1043 .maxlen
= sizeof(block_dump
),
1045 .proc_handler
= &proc_dointvec
,
1046 .strategy
= &sysctl_intvec
,
1050 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
1051 .procname
= "vfs_cache_pressure",
1052 .data
= &sysctl_vfs_cache_pressure
,
1053 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
1055 .proc_handler
= &proc_dointvec
,
1056 .strategy
= &sysctl_intvec
,
1059 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1061 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
1062 .procname
= "legacy_va_layout",
1063 .data
= &sysctl_legacy_va_layout
,
1064 .maxlen
= sizeof(sysctl_legacy_va_layout
),
1066 .proc_handler
= &proc_dointvec
,
1067 .strategy
= &sysctl_intvec
,
1073 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
1074 .procname
= "zone_reclaim_mode",
1075 .data
= &zone_reclaim_mode
,
1076 .maxlen
= sizeof(zone_reclaim_mode
),
1078 .proc_handler
= &proc_dointvec
,
1079 .strategy
= &sysctl_intvec
,
1083 .ctl_name
= VM_MIN_UNMAPPED
,
1084 .procname
= "min_unmapped_ratio",
1085 .data
= &sysctl_min_unmapped_ratio
,
1086 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1088 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
1089 .strategy
= &sysctl_intvec
,
1091 .extra2
= &one_hundred
,
1094 .ctl_name
= VM_MIN_SLAB
,
1095 .procname
= "min_slab_ratio",
1096 .data
= &sysctl_min_slab_ratio
,
1097 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1099 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1100 .strategy
= &sysctl_intvec
,
1102 .extra2
= &one_hundred
,
1107 .ctl_name
= CTL_UNNUMBERED
,
1108 .procname
= "stat_interval",
1109 .data
= &sysctl_stat_interval
,
1110 .maxlen
= sizeof(sysctl_stat_interval
),
1112 .proc_handler
= &proc_dointvec_jiffies
,
1113 .strategy
= &sysctl_jiffies
,
1116 #ifdef CONFIG_SECURITY
1118 .ctl_name
= CTL_UNNUMBERED
,
1119 .procname
= "mmap_min_addr",
1120 .data
= &mmap_min_addr
,
1121 .maxlen
= sizeof(unsigned long),
1123 .proc_handler
= &proc_doulongvec_minmax
,
1128 .ctl_name
= CTL_UNNUMBERED
,
1129 .procname
= "numa_zonelist_order",
1130 .data
= &numa_zonelist_order
,
1131 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1133 .proc_handler
= &numa_zonelist_order_handler
,
1134 .strategy
= &sysctl_string
,
1137 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1138 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1140 .ctl_name
= VM_VDSO_ENABLED
,
1141 .procname
= "vdso_enabled",
1142 .data
= &vdso_enabled
,
1143 .maxlen
= sizeof(vdso_enabled
),
1145 .proc_handler
= &proc_dointvec
,
1146 .strategy
= &sysctl_intvec
,
1150 #ifdef CONFIG_HIGHMEM
1152 .ctl_name
= CTL_UNNUMBERED
,
1153 .procname
= "highmem_is_dirtyable",
1154 .data
= &vm_highmem_is_dirtyable
,
1155 .maxlen
= sizeof(vm_highmem_is_dirtyable
),
1157 .proc_handler
= &proc_dointvec_minmax
,
1158 .strategy
= &sysctl_intvec
,
1164 * NOTE: do not add new entries to this table unless you have read
1165 * Documentation/sysctl/ctl_unnumbered.txt
1170 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1171 static struct ctl_table binfmt_misc_table
[] = {
1176 static struct ctl_table fs_table
[] = {
1178 .ctl_name
= FS_NRINODE
,
1179 .procname
= "inode-nr",
1180 .data
= &inodes_stat
,
1181 .maxlen
= 2*sizeof(int),
1183 .proc_handler
= &proc_dointvec
,
1186 .ctl_name
= FS_STATINODE
,
1187 .procname
= "inode-state",
1188 .data
= &inodes_stat
,
1189 .maxlen
= 7*sizeof(int),
1191 .proc_handler
= &proc_dointvec
,
1194 .procname
= "file-nr",
1195 .data
= &files_stat
,
1196 .maxlen
= 3*sizeof(int),
1198 .proc_handler
= &proc_nr_files
,
1201 .ctl_name
= FS_MAXFILE
,
1202 .procname
= "file-max",
1203 .data
= &files_stat
.max_files
,
1204 .maxlen
= sizeof(int),
1206 .proc_handler
= &proc_dointvec
,
1209 .ctl_name
= CTL_UNNUMBERED
,
1210 .procname
= "nr_open",
1211 .data
= &sysctl_nr_open
,
1212 .maxlen
= sizeof(int),
1214 .proc_handler
= &proc_dointvec_minmax
,
1215 .extra1
= &sysctl_nr_open_min
,
1216 .extra2
= &sysctl_nr_open_max
,
1219 .ctl_name
= FS_DENTRY
,
1220 .procname
= "dentry-state",
1221 .data
= &dentry_stat
,
1222 .maxlen
= 6*sizeof(int),
1224 .proc_handler
= &proc_dointvec
,
1227 .ctl_name
= FS_OVERFLOWUID
,
1228 .procname
= "overflowuid",
1229 .data
= &fs_overflowuid
,
1230 .maxlen
= sizeof(int),
1232 .proc_handler
= &proc_dointvec_minmax
,
1233 .strategy
= &sysctl_intvec
,
1234 .extra1
= &minolduid
,
1235 .extra2
= &maxolduid
,
1238 .ctl_name
= FS_OVERFLOWGID
,
1239 .procname
= "overflowgid",
1240 .data
= &fs_overflowgid
,
1241 .maxlen
= sizeof(int),
1243 .proc_handler
= &proc_dointvec_minmax
,
1244 .strategy
= &sysctl_intvec
,
1245 .extra1
= &minolduid
,
1246 .extra2
= &maxolduid
,
1249 .ctl_name
= FS_LEASES
,
1250 .procname
= "leases-enable",
1251 .data
= &leases_enable
,
1252 .maxlen
= sizeof(int),
1254 .proc_handler
= &proc_dointvec
,
1256 #ifdef CONFIG_DNOTIFY
1258 .ctl_name
= FS_DIR_NOTIFY
,
1259 .procname
= "dir-notify-enable",
1260 .data
= &dir_notify_enable
,
1261 .maxlen
= sizeof(int),
1263 .proc_handler
= &proc_dointvec
,
1268 .ctl_name
= FS_LEASE_TIME
,
1269 .procname
= "lease-break-time",
1270 .data
= &lease_break_time
,
1271 .maxlen
= sizeof(int),
1273 .proc_handler
= &proc_dointvec_minmax
,
1274 .strategy
= &sysctl_intvec
,
1279 .procname
= "aio-nr",
1281 .maxlen
= sizeof(aio_nr
),
1283 .proc_handler
= &proc_doulongvec_minmax
,
1286 .procname
= "aio-max-nr",
1287 .data
= &aio_max_nr
,
1288 .maxlen
= sizeof(aio_max_nr
),
1290 .proc_handler
= &proc_doulongvec_minmax
,
1292 #ifdef CONFIG_INOTIFY_USER
1294 .ctl_name
= FS_INOTIFY
,
1295 .procname
= "inotify",
1297 .child
= inotify_table
,
1302 .ctl_name
= KERN_SETUID_DUMPABLE
,
1303 .procname
= "suid_dumpable",
1304 .data
= &suid_dumpable
,
1305 .maxlen
= sizeof(int),
1307 .proc_handler
= &proc_dointvec
,
1309 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1311 .ctl_name
= CTL_UNNUMBERED
,
1312 .procname
= "binfmt_misc",
1314 .child
= binfmt_misc_table
,
1318 * NOTE: do not add new entries to this table unless you have read
1319 * Documentation/sysctl/ctl_unnumbered.txt
1324 static struct ctl_table debug_table
[] = {
1325 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1327 .ctl_name
= CTL_UNNUMBERED
,
1328 .procname
= "exception-trace",
1329 .data
= &show_unhandled_signals
,
1330 .maxlen
= sizeof(int),
1332 .proc_handler
= proc_dointvec
1338 static struct ctl_table dev_table
[] = {
1342 static DEFINE_SPINLOCK(sysctl_lock
);
1344 /* called under sysctl_lock */
1345 static int use_table(struct ctl_table_header
*p
)
1347 if (unlikely(p
->unregistering
))
1353 /* called under sysctl_lock */
1354 static void unuse_table(struct ctl_table_header
*p
)
1357 if (unlikely(p
->unregistering
))
1358 complete(p
->unregistering
);
1361 /* called under sysctl_lock, will reacquire if has to wait */
1362 static void start_unregistering(struct ctl_table_header
*p
)
1365 * if p->used is 0, nobody will ever touch that entry again;
1366 * we'll eliminate all paths to it before dropping sysctl_lock
1368 if (unlikely(p
->used
)) {
1369 struct completion wait
;
1370 init_completion(&wait
);
1371 p
->unregistering
= &wait
;
1372 spin_unlock(&sysctl_lock
);
1373 wait_for_completion(&wait
);
1374 spin_lock(&sysctl_lock
);
1377 * do not remove from the list until nobody holds it; walking the
1378 * list in do_sysctl() relies on that.
1380 list_del_init(&p
->ctl_entry
);
1383 void sysctl_head_finish(struct ctl_table_header
*head
)
1387 spin_lock(&sysctl_lock
);
1389 spin_unlock(&sysctl_lock
);
1392 static struct list_head
*
1393 lookup_header_list(struct ctl_table_root
*root
, struct nsproxy
*namespaces
)
1395 struct list_head
*header_list
;
1396 header_list
= &root
->header_list
;
1398 header_list
= root
->lookup(root
, namespaces
);
1402 struct ctl_table_header
*__sysctl_head_next(struct nsproxy
*namespaces
,
1403 struct ctl_table_header
*prev
)
1405 struct ctl_table_root
*root
;
1406 struct list_head
*header_list
;
1407 struct ctl_table_header
*head
;
1408 struct list_head
*tmp
;
1410 spin_lock(&sysctl_lock
);
1413 tmp
= &prev
->ctl_entry
;
1417 tmp
= &root_table_header
.ctl_entry
;
1419 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1421 if (!use_table(head
))
1423 spin_unlock(&sysctl_lock
);
1428 header_list
= lookup_header_list(root
, namespaces
);
1429 if (tmp
!= header_list
)
1433 root
= list_entry(root
->root_list
.next
,
1434 struct ctl_table_root
, root_list
);
1435 if (root
== &sysctl_table_root
)
1437 header_list
= lookup_header_list(root
, namespaces
);
1438 } while (list_empty(header_list
));
1439 tmp
= header_list
->next
;
1442 spin_unlock(&sysctl_lock
);
1446 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1448 return __sysctl_head_next(current
->nsproxy
, prev
);
1451 void register_sysctl_root(struct ctl_table_root
*root
)
1453 spin_lock(&sysctl_lock
);
1454 list_add_tail(&root
->root_list
, &sysctl_table_root
.root_list
);
1455 spin_unlock(&sysctl_lock
);
1458 #ifdef CONFIG_SYSCTL_SYSCALL
1459 /* Perform the actual read/write of a sysctl table entry. */
1460 static int do_sysctl_strategy(struct ctl_table_root
*root
,
1461 struct ctl_table
*table
,
1462 int __user
*name
, int nlen
,
1463 void __user
*oldval
, size_t __user
*oldlenp
,
1464 void __user
*newval
, size_t newlen
)
1472 if (sysctl_perm(root
, table
, op
))
1475 if (table
->strategy
) {
1476 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1484 /* If there is no strategy routine, or if the strategy returns
1485 * zero, proceed with automatic r/w */
1486 if (table
->data
&& table
->maxlen
) {
1487 rc
= sysctl_data(table
, name
, nlen
, oldval
, oldlenp
,
1495 static int parse_table(int __user
*name
, int nlen
,
1496 void __user
*oldval
, size_t __user
*oldlenp
,
1497 void __user
*newval
, size_t newlen
,
1498 struct ctl_table_root
*root
,
1499 struct ctl_table
*table
)
1505 if (get_user(n
, name
))
1507 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1508 if (!table
->ctl_name
)
1510 if (n
== table
->ctl_name
) {
1513 if (sysctl_perm(root
, table
, 001))
1517 table
= table
->child
;
1520 error
= do_sysctl_strategy(root
, table
, name
, nlen
,
1529 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1530 void __user
*newval
, size_t newlen
)
1532 struct ctl_table_header
*head
;
1533 int error
= -ENOTDIR
;
1535 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1539 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1543 for (head
= sysctl_head_next(NULL
); head
;
1544 head
= sysctl_head_next(head
)) {
1545 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1547 head
->root
, head
->ctl_table
);
1548 if (error
!= -ENOTDIR
) {
1549 sysctl_head_finish(head
);
1556 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1558 struct __sysctl_args tmp
;
1561 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1564 error
= deprecated_sysctl_warning(&tmp
);
1569 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1570 tmp
.newval
, tmp
.newlen
);
1575 #endif /* CONFIG_SYSCTL_SYSCALL */
1578 * sysctl_perm does NOT grant the superuser all rights automatically, because
1579 * some sysctl variables are readonly even to root.
1582 static int test_perm(int mode
, int op
)
1586 else if (in_egroup_p(0))
1588 if ((mode
& op
& 0007) == op
)
1593 int sysctl_perm(struct ctl_table_root
*root
, struct ctl_table
*table
, int op
)
1598 error
= security_sysctl(table
, op
);
1602 if (root
->permissions
)
1603 mode
= root
->permissions(root
, current
->nsproxy
, table
);
1607 return test_perm(mode
, op
);
1610 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1612 for (; table
->ctl_name
|| table
->procname
; table
++) {
1613 table
->parent
= parent
;
1615 sysctl_set_parent(table
, table
->child
);
1619 static __init
int sysctl_init(void)
1621 sysctl_set_parent(NULL
, root_table
);
1622 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1625 err
= sysctl_check_table(current
->nsproxy
, root_table
);
1631 core_initcall(sysctl_init
);
1634 * __register_sysctl_paths - register a sysctl hierarchy
1635 * @root: List of sysctl headers to register on
1636 * @namespaces: Data to compute which lists of sysctl entries are visible
1637 * @path: The path to the directory the sysctl table is in.
1638 * @table: the top-level table structure
1640 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1641 * array. A completely 0 filled entry terminates the table.
1643 * The members of the &struct ctl_table structure are used as follows:
1645 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1646 * must be unique within that level of sysctl
1648 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1649 * enter a sysctl file
1651 * data - a pointer to data for use by proc_handler
1653 * maxlen - the maximum size in bytes of the data
1655 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1657 * child - a pointer to the child sysctl table if this entry is a directory, or
1660 * proc_handler - the text handler routine (described below)
1662 * strategy - the strategy routine (described below)
1664 * de - for internal use by the sysctl routines
1666 * extra1, extra2 - extra pointers usable by the proc handler routines
1668 * Leaf nodes in the sysctl tree will be represented by a single file
1669 * under /proc; non-leaf nodes will be represented by directories.
1671 * sysctl(2) can automatically manage read and write requests through
1672 * the sysctl table. The data and maxlen fields of the ctl_table
1673 * struct enable minimal validation of the values being written to be
1674 * performed, and the mode field allows minimal authentication.
1676 * More sophisticated management can be enabled by the provision of a
1677 * strategy routine with the table entry. This will be called before
1678 * any automatic read or write of the data is performed.
1680 * The strategy routine may return
1682 * < 0 - Error occurred (error is passed to user process)
1684 * 0 - OK - proceed with automatic read or write.
1686 * > 0 - OK - read or write has been done by the strategy routine, so
1687 * return immediately.
1689 * There must be a proc_handler routine for any terminal nodes
1690 * mirrored under /proc/sys (non-terminals are handled by a built-in
1691 * directory handler). Several default handlers are available to
1692 * cover common cases -
1694 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1695 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1696 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1698 * It is the handler's job to read the input buffer from user memory
1699 * and process it. The handler should return 0 on success.
1701 * This routine returns %NULL on a failure to register, and a pointer
1702 * to the table header on success.
1704 struct ctl_table_header
*__register_sysctl_paths(
1705 struct ctl_table_root
*root
,
1706 struct nsproxy
*namespaces
,
1707 const struct ctl_path
*path
, struct ctl_table
*table
)
1709 struct list_head
*header_list
;
1710 struct ctl_table_header
*header
;
1711 struct ctl_table
*new, **prevp
;
1712 unsigned int n
, npath
;
1714 /* Count the path components */
1715 for (npath
= 0; path
[npath
].ctl_name
|| path
[npath
].procname
; ++npath
)
1719 * For each path component, allocate a 2-element ctl_table array.
1720 * The first array element will be filled with the sysctl entry
1721 * for this, the second will be the sentinel (ctl_name == 0).
1723 * We allocate everything in one go so that we don't have to
1724 * worry about freeing additional memory in unregister_sysctl_table.
1726 header
= kzalloc(sizeof(struct ctl_table_header
) +
1727 (2 * npath
* sizeof(struct ctl_table
)), GFP_KERNEL
);
1731 new = (struct ctl_table
*) (header
+ 1);
1733 /* Now connect the dots */
1734 prevp
= &header
->ctl_table
;
1735 for (n
= 0; n
< npath
; ++n
, ++path
) {
1736 /* Copy the procname */
1737 new->procname
= path
->procname
;
1738 new->ctl_name
= path
->ctl_name
;
1742 prevp
= &new->child
;
1747 header
->ctl_table_arg
= table
;
1749 INIT_LIST_HEAD(&header
->ctl_entry
);
1751 header
->unregistering
= NULL
;
1752 header
->root
= root
;
1753 sysctl_set_parent(NULL
, header
->ctl_table
);
1754 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1755 if (sysctl_check_table(namespaces
, header
->ctl_table
)) {
1760 spin_lock(&sysctl_lock
);
1761 header_list
= lookup_header_list(root
, namespaces
);
1762 list_add_tail(&header
->ctl_entry
, header_list
);
1763 spin_unlock(&sysctl_lock
);
1769 * register_sysctl_table_path - register a sysctl table hierarchy
1770 * @path: The path to the directory the sysctl table is in.
1771 * @table: the top-level table structure
1773 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1774 * array. A completely 0 filled entry terminates the table.
1776 * See __register_sysctl_paths for more details.
1778 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
1779 struct ctl_table
*table
)
1781 return __register_sysctl_paths(&sysctl_table_root
, current
->nsproxy
,
1786 * register_sysctl_table - register a sysctl table hierarchy
1787 * @table: the top-level table structure
1789 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1790 * array. A completely 0 filled entry terminates the table.
1792 * See register_sysctl_paths for more details.
1794 struct ctl_table_header
*register_sysctl_table(struct ctl_table
*table
)
1796 static const struct ctl_path null_path
[] = { {} };
1798 return register_sysctl_paths(null_path
, table
);
1802 * unregister_sysctl_table - unregister a sysctl table hierarchy
1803 * @header: the header returned from register_sysctl_table
1805 * Unregisters the sysctl table and all children. proc entries may not
1806 * actually be removed until they are no longer used by anyone.
1808 void unregister_sysctl_table(struct ctl_table_header
* header
)
1815 spin_lock(&sysctl_lock
);
1816 start_unregistering(header
);
1817 spin_unlock(&sysctl_lock
);
1821 #else /* !CONFIG_SYSCTL */
1822 struct ctl_table_header
*register_sysctl_table(struct ctl_table
* table
)
1827 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
1828 struct ctl_table
*table
)
1833 void unregister_sysctl_table(struct ctl_table_header
* table
)
1837 #endif /* CONFIG_SYSCTL */
1843 #ifdef CONFIG_PROC_SYSCTL
1845 static int _proc_do_string(void* data
, int maxlen
, int write
,
1846 struct file
*filp
, void __user
*buffer
,
1847 size_t *lenp
, loff_t
*ppos
)
1853 if (!data
|| !maxlen
|| !*lenp
) {
1861 while (len
< *lenp
) {
1862 if (get_user(c
, p
++))
1864 if (c
== 0 || c
== '\n')
1870 if(copy_from_user(data
, buffer
, len
))
1872 ((char *) data
)[len
] = 0;
1890 if(copy_to_user(buffer
, data
, len
))
1893 if(put_user('\n', ((char __user
*) buffer
) + len
))
1904 * proc_dostring - read a string sysctl
1905 * @table: the sysctl table
1906 * @write: %TRUE if this is a write to the sysctl file
1907 * @filp: the file structure
1908 * @buffer: the user buffer
1909 * @lenp: the size of the user buffer
1910 * @ppos: file position
1912 * Reads/writes a string from/to the user buffer. If the kernel
1913 * buffer provided is not large enough to hold the string, the
1914 * string is truncated. The copied string is %NULL-terminated.
1915 * If the string is being read by the user process, it is copied
1916 * and a newline '\n' is added. It is truncated if the buffer is
1919 * Returns 0 on success.
1921 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
1922 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1924 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1925 buffer
, lenp
, ppos
);
1929 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1931 int write
, void *data
)
1934 *valp
= *negp
? -*lvalp
: *lvalp
;
1939 *lvalp
= (unsigned long)-val
;
1942 *lvalp
= (unsigned long)val
;
1948 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
1949 int write
, struct file
*filp
, void __user
*buffer
,
1950 size_t *lenp
, loff_t
*ppos
,
1951 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1952 int write
, void *data
),
1955 #define TMPBUFLEN 21
1956 int *i
, vleft
, first
=1, neg
, val
;
1960 char buf
[TMPBUFLEN
], *p
;
1961 char __user
*s
= buffer
;
1963 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1964 (*ppos
&& !write
)) {
1969 i
= (int *) tbl_data
;
1970 vleft
= table
->maxlen
/ sizeof(*i
);
1974 conv
= do_proc_dointvec_conv
;
1976 for (; left
&& vleft
--; i
++, first
=0) {
1991 if (len
> sizeof(buf
) - 1)
1992 len
= sizeof(buf
) - 1;
1993 if (copy_from_user(buf
, s
, len
))
1997 if (*p
== '-' && left
> 1) {
2001 if (*p
< '0' || *p
> '9')
2004 lval
= simple_strtoul(p
, &p
, 0);
2007 if ((len
< left
) && *p
&& !isspace(*p
))
2014 if (conv(&neg
, &lval
, i
, 1, data
))
2021 if (conv(&neg
, &lval
, i
, 0, data
))
2024 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
2028 if(copy_to_user(s
, buf
, len
))
2035 if (!write
&& !first
&& left
) {
2036 if(put_user('\n', s
))
2043 if (get_user(c
, s
++))
2058 static int do_proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2059 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
2060 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
2061 int write
, void *data
),
2064 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
2065 buffer
, lenp
, ppos
, conv
, data
);
2069 * proc_dointvec - read a vector of integers
2070 * @table: the sysctl table
2071 * @write: %TRUE if this is a write to the sysctl file
2072 * @filp: the file structure
2073 * @buffer: the user buffer
2074 * @lenp: the size of the user buffer
2075 * @ppos: file position
2077 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2078 * values from/to the user buffer, treated as an ASCII string.
2080 * Returns 0 on success.
2082 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2083 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2085 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2093 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
2095 int write
, void *data
)
2097 int op
= *(int *)data
;
2099 int val
= *negp
? -*lvalp
: *lvalp
;
2101 case OP_SET
: *valp
= val
; break;
2102 case OP_AND
: *valp
&= val
; break;
2103 case OP_OR
: *valp
|= val
; break;
2109 *lvalp
= (unsigned long)-val
;
2112 *lvalp
= (unsigned long)val
;
2119 * Taint values can only be increased
2121 static int proc_dointvec_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
2122 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2126 if (write
&& !capable(CAP_SYS_ADMIN
))
2130 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2131 do_proc_dointvec_bset_conv
,&op
);
2134 struct do_proc_dointvec_minmax_conv_param
{
2139 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
2141 int write
, void *data
)
2143 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
2145 int val
= *negp
? -*lvalp
: *lvalp
;
2146 if ((param
->min
&& *param
->min
> val
) ||
2147 (param
->max
&& *param
->max
< val
))
2154 *lvalp
= (unsigned long)-val
;
2157 *lvalp
= (unsigned long)val
;
2164 * proc_dointvec_minmax - read a vector of integers with min/max values
2165 * @table: the sysctl table
2166 * @write: %TRUE if this is a write to the sysctl file
2167 * @filp: the file structure
2168 * @buffer: the user buffer
2169 * @lenp: the size of the user buffer
2170 * @ppos: file position
2172 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2173 * values from/to the user buffer, treated as an ASCII string.
2175 * This routine will ensure the values are within the range specified by
2176 * table->extra1 (min) and table->extra2 (max).
2178 * Returns 0 on success.
2180 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2181 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2183 struct do_proc_dointvec_minmax_conv_param param
= {
2184 .min
= (int *) table
->extra1
,
2185 .max
= (int *) table
->extra2
,
2187 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2188 do_proc_dointvec_minmax_conv
, ¶m
);
2191 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
2193 void __user
*buffer
,
2194 size_t *lenp
, loff_t
*ppos
,
2195 unsigned long convmul
,
2196 unsigned long convdiv
)
2198 #define TMPBUFLEN 21
2199 unsigned long *i
, *min
, *max
, val
;
2200 int vleft
, first
=1, neg
;
2202 char buf
[TMPBUFLEN
], *p
;
2203 char __user
*s
= buffer
;
2205 if (!data
|| !table
->maxlen
|| !*lenp
||
2206 (*ppos
&& !write
)) {
2211 i
= (unsigned long *) data
;
2212 min
= (unsigned long *) table
->extra1
;
2213 max
= (unsigned long *) table
->extra2
;
2214 vleft
= table
->maxlen
/ sizeof(unsigned long);
2217 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
2232 if (len
> TMPBUFLEN
-1)
2234 if (copy_from_user(buf
, s
, len
))
2238 if (*p
== '-' && left
> 1) {
2242 if (*p
< '0' || *p
> '9')
2244 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2246 if ((len
< left
) && *p
&& !isspace(*p
))
2255 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2262 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2266 if(copy_to_user(s
, buf
, len
))
2273 if (!write
&& !first
&& left
) {
2274 if(put_user('\n', s
))
2281 if (get_user(c
, s
++))
2296 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2298 void __user
*buffer
,
2299 size_t *lenp
, loff_t
*ppos
,
2300 unsigned long convmul
,
2301 unsigned long convdiv
)
2303 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2304 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2308 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2309 * @table: the sysctl table
2310 * @write: %TRUE if this is a write to the sysctl file
2311 * @filp: the file structure
2312 * @buffer: the user buffer
2313 * @lenp: the size of the user buffer
2314 * @ppos: file position
2316 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2317 * values from/to the user buffer, treated as an ASCII string.
2319 * This routine will ensure the values are within the range specified by
2320 * table->extra1 (min) and table->extra2 (max).
2322 * Returns 0 on success.
2324 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2325 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2327 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2331 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2332 * @table: the sysctl table
2333 * @write: %TRUE if this is a write to the sysctl file
2334 * @filp: the file structure
2335 * @buffer: the user buffer
2336 * @lenp: the size of the user buffer
2337 * @ppos: file position
2339 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2340 * values from/to the user buffer, treated as an ASCII string. The values
2341 * are treated as milliseconds, and converted to jiffies when they are stored.
2343 * This routine will ensure the values are within the range specified by
2344 * table->extra1 (min) and table->extra2 (max).
2346 * Returns 0 on success.
2348 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2350 void __user
*buffer
,
2351 size_t *lenp
, loff_t
*ppos
)
2353 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2354 lenp
, ppos
, HZ
, 1000l);
2358 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2360 int write
, void *data
)
2363 if (*lvalp
> LONG_MAX
/ HZ
)
2365 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2371 lval
= (unsigned long)-val
;
2374 lval
= (unsigned long)val
;
2381 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2383 int write
, void *data
)
2386 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2388 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2394 lval
= (unsigned long)-val
;
2397 lval
= (unsigned long)val
;
2399 *lvalp
= jiffies_to_clock_t(lval
);
2404 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2406 int write
, void *data
)
2409 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2415 lval
= (unsigned long)-val
;
2418 lval
= (unsigned long)val
;
2420 *lvalp
= jiffies_to_msecs(lval
);
2426 * proc_dointvec_jiffies - read a vector of integers as seconds
2427 * @table: the sysctl table
2428 * @write: %TRUE if this is a write to the sysctl file
2429 * @filp: the file structure
2430 * @buffer: the user buffer
2431 * @lenp: the size of the user buffer
2432 * @ppos: file position
2434 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2435 * values from/to the user buffer, treated as an ASCII string.
2436 * The values read are assumed to be in seconds, and are converted into
2439 * Returns 0 on success.
2441 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2442 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2444 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2445 do_proc_dointvec_jiffies_conv
,NULL
);
2449 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2450 * @table: the sysctl table
2451 * @write: %TRUE if this is a write to the sysctl file
2452 * @filp: the file structure
2453 * @buffer: the user buffer
2454 * @lenp: the size of the user buffer
2455 * @ppos: pointer to the file position
2457 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2458 * values from/to the user buffer, treated as an ASCII string.
2459 * The values read are assumed to be in 1/USER_HZ seconds, and
2460 * are converted into jiffies.
2462 * Returns 0 on success.
2464 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2465 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2467 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2468 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2472 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2473 * @table: the sysctl table
2474 * @write: %TRUE if this is a write to the sysctl file
2475 * @filp: the file structure
2476 * @buffer: the user buffer
2477 * @lenp: the size of the user buffer
2478 * @ppos: file position
2479 * @ppos: the current position in the file
2481 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2482 * values from/to the user buffer, treated as an ASCII string.
2483 * The values read are assumed to be in 1/1000 seconds, and
2484 * are converted into jiffies.
2486 * Returns 0 on success.
2488 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2489 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2491 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2492 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2495 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
2496 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2498 struct pid
*new_pid
;
2502 tmp
= pid_vnr(cad_pid
);
2504 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2505 lenp
, ppos
, NULL
, NULL
);
2509 new_pid
= find_get_pid(tmp
);
2513 put_pid(xchg(&cad_pid
, new_pid
));
2517 #else /* CONFIG_PROC_FS */
2519 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2520 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2525 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2526 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2531 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2532 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2537 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2538 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2543 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2544 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2549 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2550 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2555 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2556 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2561 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2563 void __user
*buffer
,
2564 size_t *lenp
, loff_t
*ppos
)
2570 #endif /* CONFIG_PROC_FS */
2573 #ifdef CONFIG_SYSCTL_SYSCALL
2575 * General sysctl support routines
2578 /* The generic sysctl data routine (used if no strategy routine supplied) */
2579 int sysctl_data(struct ctl_table
*table
, int __user
*name
, int nlen
,
2580 void __user
*oldval
, size_t __user
*oldlenp
,
2581 void __user
*newval
, size_t newlen
)
2585 /* Get out of I don't have a variable */
2586 if (!table
->data
|| !table
->maxlen
)
2589 if (oldval
&& oldlenp
) {
2590 if (get_user(len
, oldlenp
))
2593 if (len
> table
->maxlen
)
2594 len
= table
->maxlen
;
2595 if (copy_to_user(oldval
, table
->data
, len
))
2597 if (put_user(len
, oldlenp
))
2602 if (newval
&& newlen
) {
2603 if (newlen
> table
->maxlen
)
2604 newlen
= table
->maxlen
;
2606 if (copy_from_user(table
->data
, newval
, newlen
))
2612 /* The generic string strategy routine: */
2613 int sysctl_string(struct ctl_table
*table
, int __user
*name
, int nlen
,
2614 void __user
*oldval
, size_t __user
*oldlenp
,
2615 void __user
*newval
, size_t newlen
)
2617 if (!table
->data
|| !table
->maxlen
)
2620 if (oldval
&& oldlenp
) {
2622 if (get_user(bufsize
, oldlenp
))
2625 size_t len
= strlen(table
->data
), copied
;
2627 /* This shouldn't trigger for a well-formed sysctl */
2628 if (len
> table
->maxlen
)
2629 len
= table
->maxlen
;
2631 /* Copy up to a max of bufsize-1 bytes of the string */
2632 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2634 if (copy_to_user(oldval
, table
->data
, copied
) ||
2635 put_user(0, (char __user
*)(oldval
+ copied
)))
2637 if (put_user(len
, oldlenp
))
2641 if (newval
&& newlen
) {
2642 size_t len
= newlen
;
2643 if (len
> table
->maxlen
)
2644 len
= table
->maxlen
;
2645 if(copy_from_user(table
->data
, newval
, len
))
2647 if (len
== table
->maxlen
)
2649 ((char *) table
->data
)[len
] = 0;
2655 * This function makes sure that all of the integers in the vector
2656 * are between the minimum and maximum values given in the arrays
2657 * table->extra1 and table->extra2, respectively.
2659 int sysctl_intvec(struct ctl_table
*table
, int __user
*name
, int nlen
,
2660 void __user
*oldval
, size_t __user
*oldlenp
,
2661 void __user
*newval
, size_t newlen
)
2664 if (newval
&& newlen
) {
2665 int __user
*vec
= (int __user
*) newval
;
2666 int *min
= (int *) table
->extra1
;
2667 int *max
= (int *) table
->extra2
;
2671 if (newlen
% sizeof(int) != 0)
2674 if (!table
->extra1
&& !table
->extra2
)
2677 if (newlen
> table
->maxlen
)
2678 newlen
= table
->maxlen
;
2679 length
= newlen
/ sizeof(int);
2681 for (i
= 0; i
< length
; i
++) {
2683 if (get_user(value
, vec
+ i
))
2685 if (min
&& value
< min
[i
])
2687 if (max
&& value
> max
[i
])
2694 /* Strategy function to convert jiffies to seconds */
2695 int sysctl_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2696 void __user
*oldval
, size_t __user
*oldlenp
,
2697 void __user
*newval
, size_t newlen
)
2699 if (oldval
&& oldlenp
) {
2702 if (get_user(olen
, oldlenp
))
2707 if (olen
< sizeof(int))
2710 val
= *(int *)(table
->data
) / HZ
;
2711 if (put_user(val
, (int __user
*)oldval
))
2713 if (put_user(sizeof(int), oldlenp
))
2717 if (newval
&& newlen
) {
2719 if (newlen
!= sizeof(int))
2721 if (get_user(new, (int __user
*)newval
))
2723 *(int *)(table
->data
) = new*HZ
;
2728 /* Strategy function to convert jiffies to seconds */
2729 int sysctl_ms_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2730 void __user
*oldval
, size_t __user
*oldlenp
,
2731 void __user
*newval
, size_t newlen
)
2733 if (oldval
&& oldlenp
) {
2736 if (get_user(olen
, oldlenp
))
2741 if (olen
< sizeof(int))
2744 val
= jiffies_to_msecs(*(int *)(table
->data
));
2745 if (put_user(val
, (int __user
*)oldval
))
2747 if (put_user(sizeof(int), oldlenp
))
2751 if (newval
&& newlen
) {
2753 if (newlen
!= sizeof(int))
2755 if (get_user(new, (int __user
*)newval
))
2757 *(int *)(table
->data
) = msecs_to_jiffies(new);
2764 #else /* CONFIG_SYSCTL_SYSCALL */
2767 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2769 struct __sysctl_args tmp
;
2772 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2775 error
= deprecated_sysctl_warning(&tmp
);
2777 /* If no error reading the parameters then just -ENOSYS ... */
2784 int sysctl_data(struct ctl_table
*table
, int __user
*name
, int nlen
,
2785 void __user
*oldval
, size_t __user
*oldlenp
,
2786 void __user
*newval
, size_t newlen
)
2791 int sysctl_string(struct ctl_table
*table
, int __user
*name
, int nlen
,
2792 void __user
*oldval
, size_t __user
*oldlenp
,
2793 void __user
*newval
, size_t newlen
)
2798 int sysctl_intvec(struct ctl_table
*table
, int __user
*name
, int nlen
,
2799 void __user
*oldval
, size_t __user
*oldlenp
,
2800 void __user
*newval
, size_t newlen
)
2805 int sysctl_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2806 void __user
*oldval
, size_t __user
*oldlenp
,
2807 void __user
*newval
, size_t newlen
)
2812 int sysctl_ms_jiffies(struct ctl_table
*table
, int __user
*name
, int nlen
,
2813 void __user
*oldval
, size_t __user
*oldlenp
,
2814 void __user
*newval
, size_t newlen
)
2819 #endif /* CONFIG_SYSCTL_SYSCALL */
2821 static int deprecated_sysctl_warning(struct __sysctl_args
*args
)
2823 static int msg_count
;
2824 int name
[CTL_MAXNAME
];
2827 /* Check args->nlen. */
2828 if (args
->nlen
< 0 || args
->nlen
> CTL_MAXNAME
)
2831 /* Read in the sysctl name for better debug message logging */
2832 for (i
= 0; i
< args
->nlen
; i
++)
2833 if (get_user(name
[i
], args
->name
+ i
))
2836 /* Ignore accesses to kernel.version */
2837 if ((args
->nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2840 if (msg_count
< 5) {
2843 "warning: process `%s' used the deprecated sysctl "
2844 "system call with ", current
->comm
);
2845 for (i
= 0; i
< args
->nlen
; i
++)
2846 printk("%d.", name
[i
]);
2853 * No sense putting this after each symbol definition, twice,
2854 * exception granted :-)
2856 EXPORT_SYMBOL(proc_dointvec
);
2857 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2858 EXPORT_SYMBOL(proc_dointvec_minmax
);
2859 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2860 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2861 EXPORT_SYMBOL(proc_dostring
);
2862 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2863 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2864 EXPORT_SYMBOL(register_sysctl_table
);
2865 EXPORT_SYMBOL(register_sysctl_paths
);
2866 EXPORT_SYMBOL(sysctl_intvec
);
2867 EXPORT_SYMBOL(sysctl_jiffies
);
2868 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2869 EXPORT_SYMBOL(sysctl_string
);
2870 EXPORT_SYMBOL(sysctl_data
);
2871 EXPORT_SYMBOL(unregister_sysctl_table
);