2 * sysctl.c: General linux system control interface
4 * Begun 24 March 1995, Stephen Tweedie
5 * Added /proc support, Dec 1995
6 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9 * Dynamic registration fixes, Stephen Tweedie.
10 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
13 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
17 * The list_for_each() macro wasn't appropriate for the sysctl loop.
18 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
21 #include <linux/module.h>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/security.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/smp_lock.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/initrd.h>
41 #include <linux/key.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/vmstat.h>
47 #include <linux/nfs_fs.h>
48 #include <linux/acpi.h>
49 #include <linux/reboot.h>
50 #include <linux/ftrace.h>
52 #include <asm/uaccess.h>
53 #include <asm/processor.h>
57 #include <asm/stacktrace.h>
61 static int deprecated_sysctl_warning(struct __sysctl_args
*args
);
63 #if defined(CONFIG_SYSCTL)
65 /* External variables not in a header file. */
67 extern int print_fatal_signals
;
68 extern int sysctl_overcommit_memory
;
69 extern int sysctl_overcommit_ratio
;
70 extern int sysctl_panic_on_oom
;
71 extern int sysctl_oom_kill_allocating_task
;
72 extern int sysctl_oom_dump_tasks
;
73 extern int max_threads
;
74 extern int core_uses_pid
;
75 extern int suid_dumpable
;
76 extern char core_pattern
[];
78 extern int min_free_kbytes
;
79 extern int pid_max_min
, pid_max_max
;
80 extern int sysctl_drop_caches
;
81 extern int percpu_pagelist_fraction
;
82 extern int compat_log
;
83 extern int latencytop_enabled
;
84 extern int sysctl_nr_open_min
, sysctl_nr_open_max
;
85 #ifdef CONFIG_RCU_TORTURE_TEST
86 extern int rcutorture_runnable
;
87 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
89 /* Constants used for minimum and maximum */
90 #ifdef CONFIG_DETECT_SOFTLOCKUP
91 static int sixty
= 60;
92 static int neg_one
= -1;
95 #if defined(CONFIG_MMU) && defined(CONFIG_FILE_LOCKING)
101 static int one_hundred
= 100;
103 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
104 static int maxolduid
= 65535;
105 static int minolduid
;
106 static int min_percpu_pagelist_fract
= 8;
108 static int ngroups_max
= NGROUPS_MAX
;
110 #ifdef CONFIG_MODULES
111 extern char modprobe_path
[];
113 #ifdef CONFIG_CHR_DEV_SG
114 extern int sg_big_buff
;
118 #include <asm/system.h>
121 #ifdef CONFIG_SPARC64
122 extern int sysctl_tsb_ratio
;
126 extern int pwrsw_enabled
;
127 extern int unaligned_enabled
;
131 #ifdef CONFIG_MATHEMU
132 extern int sysctl_ieee_emulation_warnings
;
134 extern int sysctl_userprocess_debug
;
135 extern int spin_retry
;
138 #ifdef CONFIG_BSD_PROCESS_ACCT
139 extern int acct_parm
[];
143 extern int no_unaligned_warning
;
146 #ifdef CONFIG_RT_MUTEXES
147 extern int max_lock_depth
;
150 #ifdef CONFIG_PROC_SYSCTL
151 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
152 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
153 static int proc_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
154 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
157 static struct ctl_table root_table
[];
158 static struct ctl_table_root sysctl_table_root
;
159 static struct ctl_table_header root_table_header
= {
161 .ctl_table
= root_table
,
162 .ctl_entry
= LIST_HEAD_INIT(sysctl_table_root
.default_set
.list
),
163 .root
= &sysctl_table_root
,
164 .set
= &sysctl_table_root
.default_set
,
166 static struct ctl_table_root sysctl_table_root
= {
167 .root_list
= LIST_HEAD_INIT(sysctl_table_root
.root_list
),
168 .default_set
.list
= LIST_HEAD_INIT(root_table_header
.ctl_entry
),
171 static struct ctl_table kern_table
[];
172 static struct ctl_table vm_table
[];
173 static struct ctl_table fs_table
[];
174 static struct ctl_table debug_table
[];
175 static struct ctl_table dev_table
[];
176 extern struct ctl_table random_table
[];
177 #ifdef CONFIG_INOTIFY_USER
178 extern struct ctl_table inotify_table
[];
181 extern struct ctl_table epoll_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_shares_ratelimit",
276 .data
= &sysctl_sched_shares_ratelimit
,
277 .maxlen
= sizeof(unsigned int),
279 .proc_handler
= &proc_dointvec
,
282 .ctl_name
= CTL_UNNUMBERED
,
283 .procname
= "sched_shares_thresh",
284 .data
= &sysctl_sched_shares_thresh
,
285 .maxlen
= sizeof(unsigned int),
287 .proc_handler
= &proc_dointvec_minmax
,
288 .strategy
= &sysctl_intvec
,
292 .ctl_name
= CTL_UNNUMBERED
,
293 .procname
= "sched_child_runs_first",
294 .data
= &sysctl_sched_child_runs_first
,
295 .maxlen
= sizeof(unsigned int),
297 .proc_handler
= &proc_dointvec
,
300 .ctl_name
= CTL_UNNUMBERED
,
301 .procname
= "sched_features",
302 .data
= &sysctl_sched_features
,
303 .maxlen
= sizeof(unsigned int),
305 .proc_handler
= &proc_dointvec
,
308 .ctl_name
= CTL_UNNUMBERED
,
309 .procname
= "sched_migration_cost",
310 .data
= &sysctl_sched_migration_cost
,
311 .maxlen
= sizeof(unsigned int),
313 .proc_handler
= &proc_dointvec
,
316 .ctl_name
= CTL_UNNUMBERED
,
317 .procname
= "sched_nr_migrate",
318 .data
= &sysctl_sched_nr_migrate
,
319 .maxlen
= sizeof(unsigned int),
321 .proc_handler
= &proc_dointvec
,
325 .ctl_name
= CTL_UNNUMBERED
,
326 .procname
= "sched_rt_period_us",
327 .data
= &sysctl_sched_rt_period
,
328 .maxlen
= sizeof(unsigned int),
330 .proc_handler
= &sched_rt_handler
,
333 .ctl_name
= CTL_UNNUMBERED
,
334 .procname
= "sched_rt_runtime_us",
335 .data
= &sysctl_sched_rt_runtime
,
336 .maxlen
= sizeof(int),
338 .proc_handler
= &sched_rt_handler
,
341 .ctl_name
= CTL_UNNUMBERED
,
342 .procname
= "sched_compat_yield",
343 .data
= &sysctl_sched_compat_yield
,
344 .maxlen
= sizeof(unsigned int),
346 .proc_handler
= &proc_dointvec
,
348 #ifdef CONFIG_PROVE_LOCKING
350 .ctl_name
= CTL_UNNUMBERED
,
351 .procname
= "prove_locking",
352 .data
= &prove_locking
,
353 .maxlen
= sizeof(int),
355 .proc_handler
= &proc_dointvec
,
358 #ifdef CONFIG_LOCK_STAT
360 .ctl_name
= CTL_UNNUMBERED
,
361 .procname
= "lock_stat",
363 .maxlen
= sizeof(int),
365 .proc_handler
= &proc_dointvec
,
369 .ctl_name
= KERN_PANIC
,
371 .data
= &panic_timeout
,
372 .maxlen
= sizeof(int),
374 .proc_handler
= &proc_dointvec
,
377 .ctl_name
= KERN_CORE_USES_PID
,
378 .procname
= "core_uses_pid",
379 .data
= &core_uses_pid
,
380 .maxlen
= sizeof(int),
382 .proc_handler
= &proc_dointvec
,
385 .ctl_name
= KERN_CORE_PATTERN
,
386 .procname
= "core_pattern",
387 .data
= core_pattern
,
388 .maxlen
= CORENAME_MAX_SIZE
,
390 .proc_handler
= &proc_dostring
,
391 .strategy
= &sysctl_string
,
393 #ifdef CONFIG_PROC_SYSCTL
395 .procname
= "tainted",
396 .maxlen
= sizeof(long),
398 .proc_handler
= &proc_taint
,
401 #ifdef CONFIG_LATENCYTOP
403 .procname
= "latencytop",
404 .data
= &latencytop_enabled
,
405 .maxlen
= sizeof(int),
407 .proc_handler
= &proc_dointvec
,
410 #ifdef CONFIG_BLK_DEV_INITRD
412 .ctl_name
= KERN_REALROOTDEV
,
413 .procname
= "real-root-dev",
414 .data
= &real_root_dev
,
415 .maxlen
= sizeof(int),
417 .proc_handler
= &proc_dointvec
,
421 .ctl_name
= CTL_UNNUMBERED
,
422 .procname
= "print-fatal-signals",
423 .data
= &print_fatal_signals
,
424 .maxlen
= sizeof(int),
426 .proc_handler
= &proc_dointvec
,
430 .ctl_name
= KERN_SPARC_REBOOT
,
431 .procname
= "reboot-cmd",
432 .data
= reboot_command
,
435 .proc_handler
= &proc_dostring
,
436 .strategy
= &sysctl_string
,
439 .ctl_name
= KERN_SPARC_STOP_A
,
440 .procname
= "stop-a",
441 .data
= &stop_a_enabled
,
442 .maxlen
= sizeof (int),
444 .proc_handler
= &proc_dointvec
,
447 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
448 .procname
= "scons-poweroff",
449 .data
= &scons_pwroff
,
450 .maxlen
= sizeof (int),
452 .proc_handler
= &proc_dointvec
,
455 #ifdef CONFIG_SPARC64
457 .ctl_name
= CTL_UNNUMBERED
,
458 .procname
= "tsb-ratio",
459 .data
= &sysctl_tsb_ratio
,
460 .maxlen
= sizeof (int),
462 .proc_handler
= &proc_dointvec
,
467 .ctl_name
= KERN_HPPA_PWRSW
,
468 .procname
= "soft-power",
469 .data
= &pwrsw_enabled
,
470 .maxlen
= sizeof (int),
472 .proc_handler
= &proc_dointvec
,
475 .ctl_name
= KERN_HPPA_UNALIGNED
,
476 .procname
= "unaligned-trap",
477 .data
= &unaligned_enabled
,
478 .maxlen
= sizeof (int),
480 .proc_handler
= &proc_dointvec
,
484 .ctl_name
= KERN_CTLALTDEL
,
485 .procname
= "ctrl-alt-del",
487 .maxlen
= sizeof(int),
489 .proc_handler
= &proc_dointvec
,
491 #ifdef CONFIG_FUNCTION_TRACER
493 .ctl_name
= CTL_UNNUMBERED
,
494 .procname
= "ftrace_enabled",
495 .data
= &ftrace_enabled
,
496 .maxlen
= sizeof(int),
498 .proc_handler
= &ftrace_enable_sysctl
,
501 #ifdef CONFIG_STACK_TRACER
503 .ctl_name
= CTL_UNNUMBERED
,
504 .procname
= "stack_tracer_enabled",
505 .data
= &stack_tracer_enabled
,
506 .maxlen
= sizeof(int),
508 .proc_handler
= &stack_trace_sysctl
,
511 #ifdef CONFIG_TRACING
513 .ctl_name
= CTL_UNNUMBERED
,
514 .procname
= "ftrace_dump_on_oops",
515 .data
= &ftrace_dump_on_oops
,
516 .maxlen
= sizeof(int),
518 .proc_handler
= &proc_dointvec
,
521 #ifdef CONFIG_MODULES
523 .ctl_name
= KERN_MODPROBE
,
524 .procname
= "modprobe",
525 .data
= &modprobe_path
,
526 .maxlen
= KMOD_PATH_LEN
,
528 .proc_handler
= &proc_dostring
,
529 .strategy
= &sysctl_string
,
532 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
534 .ctl_name
= KERN_HOTPLUG
,
535 .procname
= "hotplug",
536 .data
= &uevent_helper
,
537 .maxlen
= UEVENT_HELPER_PATH_LEN
,
539 .proc_handler
= &proc_dostring
,
540 .strategy
= &sysctl_string
,
543 #ifdef CONFIG_CHR_DEV_SG
545 .ctl_name
= KERN_SG_BIG_BUFF
,
546 .procname
= "sg-big-buff",
547 .data
= &sg_big_buff
,
548 .maxlen
= sizeof (int),
550 .proc_handler
= &proc_dointvec
,
553 #ifdef CONFIG_BSD_PROCESS_ACCT
555 .ctl_name
= KERN_ACCT
,
558 .maxlen
= 3*sizeof(int),
560 .proc_handler
= &proc_dointvec
,
563 #ifdef CONFIG_MAGIC_SYSRQ
565 .ctl_name
= KERN_SYSRQ
,
567 .data
= &__sysrq_enabled
,
568 .maxlen
= sizeof (int),
570 .proc_handler
= &proc_dointvec
,
573 #ifdef CONFIG_PROC_SYSCTL
575 .procname
= "cad_pid",
577 .maxlen
= sizeof (int),
579 .proc_handler
= &proc_do_cad_pid
,
583 .ctl_name
= KERN_MAX_THREADS
,
584 .procname
= "threads-max",
585 .data
= &max_threads
,
586 .maxlen
= sizeof(int),
588 .proc_handler
= &proc_dointvec
,
591 .ctl_name
= KERN_RANDOM
,
592 .procname
= "random",
594 .child
= random_table
,
597 .ctl_name
= KERN_OVERFLOWUID
,
598 .procname
= "overflowuid",
599 .data
= &overflowuid
,
600 .maxlen
= sizeof(int),
602 .proc_handler
= &proc_dointvec_minmax
,
603 .strategy
= &sysctl_intvec
,
604 .extra1
= &minolduid
,
605 .extra2
= &maxolduid
,
608 .ctl_name
= KERN_OVERFLOWGID
,
609 .procname
= "overflowgid",
610 .data
= &overflowgid
,
611 .maxlen
= sizeof(int),
613 .proc_handler
= &proc_dointvec_minmax
,
614 .strategy
= &sysctl_intvec
,
615 .extra1
= &minolduid
,
616 .extra2
= &maxolduid
,
619 #ifdef CONFIG_MATHEMU
621 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
622 .procname
= "ieee_emulation_warnings",
623 .data
= &sysctl_ieee_emulation_warnings
,
624 .maxlen
= sizeof(int),
626 .proc_handler
= &proc_dointvec
,
630 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
631 .procname
= "userprocess_debug",
632 .data
= &sysctl_userprocess_debug
,
633 .maxlen
= sizeof(int),
635 .proc_handler
= &proc_dointvec
,
639 .ctl_name
= KERN_PIDMAX
,
640 .procname
= "pid_max",
642 .maxlen
= sizeof (int),
644 .proc_handler
= &proc_dointvec_minmax
,
645 .strategy
= sysctl_intvec
,
646 .extra1
= &pid_max_min
,
647 .extra2
= &pid_max_max
,
650 .ctl_name
= KERN_PANIC_ON_OOPS
,
651 .procname
= "panic_on_oops",
652 .data
= &panic_on_oops
,
653 .maxlen
= sizeof(int),
655 .proc_handler
= &proc_dointvec
,
657 #if defined CONFIG_PRINTK
659 .ctl_name
= KERN_PRINTK
,
660 .procname
= "printk",
661 .data
= &console_loglevel
,
662 .maxlen
= 4*sizeof(int),
664 .proc_handler
= &proc_dointvec
,
667 .ctl_name
= KERN_PRINTK_RATELIMIT
,
668 .procname
= "printk_ratelimit",
669 .data
= &printk_ratelimit_state
.interval
,
670 .maxlen
= sizeof(int),
672 .proc_handler
= &proc_dointvec_jiffies
,
673 .strategy
= &sysctl_jiffies
,
676 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
677 .procname
= "printk_ratelimit_burst",
678 .data
= &printk_ratelimit_state
.burst
,
679 .maxlen
= sizeof(int),
681 .proc_handler
= &proc_dointvec
,
685 .ctl_name
= KERN_NGROUPS_MAX
,
686 .procname
= "ngroups_max",
687 .data
= &ngroups_max
,
688 .maxlen
= sizeof (int),
690 .proc_handler
= &proc_dointvec
,
692 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
694 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
695 .procname
= "unknown_nmi_panic",
696 .data
= &unknown_nmi_panic
,
697 .maxlen
= sizeof (int),
699 .proc_handler
= &proc_dointvec
,
702 .procname
= "nmi_watchdog",
703 .data
= &nmi_watchdog_enabled
,
704 .maxlen
= sizeof (int),
706 .proc_handler
= &proc_nmi_enabled
,
709 #if defined(CONFIG_X86)
711 .ctl_name
= KERN_PANIC_ON_NMI
,
712 .procname
= "panic_on_unrecovered_nmi",
713 .data
= &panic_on_unrecovered_nmi
,
714 .maxlen
= sizeof(int),
716 .proc_handler
= &proc_dointvec
,
719 .ctl_name
= KERN_BOOTLOADER_TYPE
,
720 .procname
= "bootloader_type",
721 .data
= &bootloader_type
,
722 .maxlen
= sizeof (int),
724 .proc_handler
= &proc_dointvec
,
727 .ctl_name
= CTL_UNNUMBERED
,
728 .procname
= "kstack_depth_to_print",
729 .data
= &kstack_depth_to_print
,
730 .maxlen
= sizeof(int),
732 .proc_handler
= &proc_dointvec
,
735 .ctl_name
= CTL_UNNUMBERED
,
736 .procname
= "io_delay_type",
737 .data
= &io_delay_type
,
738 .maxlen
= sizeof(int),
740 .proc_handler
= &proc_dointvec
,
743 #if defined(CONFIG_MMU)
745 .ctl_name
= KERN_RANDOMIZE
,
746 .procname
= "randomize_va_space",
747 .data
= &randomize_va_space
,
748 .maxlen
= sizeof(int),
750 .proc_handler
= &proc_dointvec
,
753 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
755 .ctl_name
= KERN_SPIN_RETRY
,
756 .procname
= "spin_retry",
758 .maxlen
= sizeof (int),
760 .proc_handler
= &proc_dointvec
,
763 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
765 .procname
= "acpi_video_flags",
766 .data
= &acpi_realmode_flags
,
767 .maxlen
= sizeof (unsigned long),
769 .proc_handler
= &proc_doulongvec_minmax
,
774 .ctl_name
= KERN_IA64_UNALIGNED
,
775 .procname
= "ignore-unaligned-usertrap",
776 .data
= &no_unaligned_warning
,
777 .maxlen
= sizeof (int),
779 .proc_handler
= &proc_dointvec
,
782 #ifdef CONFIG_DETECT_SOFTLOCKUP
784 .ctl_name
= CTL_UNNUMBERED
,
785 .procname
= "softlockup_panic",
786 .data
= &softlockup_panic
,
787 .maxlen
= sizeof(int),
789 .proc_handler
= &proc_dointvec_minmax
,
790 .strategy
= &sysctl_intvec
,
795 .ctl_name
= CTL_UNNUMBERED
,
796 .procname
= "softlockup_thresh",
797 .data
= &softlockup_thresh
,
798 .maxlen
= sizeof(int),
800 .proc_handler
= &proc_dointvec_minmax
,
801 .strategy
= &sysctl_intvec
,
806 .ctl_name
= CTL_UNNUMBERED
,
807 .procname
= "hung_task_check_count",
808 .data
= &sysctl_hung_task_check_count
,
809 .maxlen
= sizeof(unsigned long),
811 .proc_handler
= &proc_doulongvec_minmax
,
812 .strategy
= &sysctl_intvec
,
815 .ctl_name
= CTL_UNNUMBERED
,
816 .procname
= "hung_task_timeout_secs",
817 .data
= &sysctl_hung_task_timeout_secs
,
818 .maxlen
= sizeof(unsigned long),
820 .proc_handler
= &proc_doulongvec_minmax
,
821 .strategy
= &sysctl_intvec
,
824 .ctl_name
= CTL_UNNUMBERED
,
825 .procname
= "hung_task_warnings",
826 .data
= &sysctl_hung_task_warnings
,
827 .maxlen
= sizeof(unsigned long),
829 .proc_handler
= &proc_doulongvec_minmax
,
830 .strategy
= &sysctl_intvec
,
835 .ctl_name
= KERN_COMPAT_LOG
,
836 .procname
= "compat-log",
838 .maxlen
= sizeof (int),
840 .proc_handler
= &proc_dointvec
,
843 #ifdef CONFIG_RT_MUTEXES
845 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
846 .procname
= "max_lock_depth",
847 .data
= &max_lock_depth
,
848 .maxlen
= sizeof(int),
850 .proc_handler
= &proc_dointvec
,
854 .ctl_name
= CTL_UNNUMBERED
,
855 .procname
= "poweroff_cmd",
856 .data
= &poweroff_cmd
,
857 .maxlen
= POWEROFF_CMD_PATH_LEN
,
859 .proc_handler
= &proc_dostring
,
860 .strategy
= &sysctl_string
,
864 .ctl_name
= CTL_UNNUMBERED
,
867 .child
= key_sysctls
,
870 #ifdef CONFIG_RCU_TORTURE_TEST
872 .ctl_name
= CTL_UNNUMBERED
,
873 .procname
= "rcutorture_runnable",
874 .data
= &rcutorture_runnable
,
875 .maxlen
= sizeof(int),
877 .proc_handler
= &proc_dointvec
,
880 #ifdef CONFIG_UNEVICTABLE_LRU
882 .ctl_name
= CTL_UNNUMBERED
,
883 .procname
= "scan_unevictable_pages",
884 .data
= &scan_unevictable_pages
,
885 .maxlen
= sizeof(scan_unevictable_pages
),
887 .proc_handler
= &scan_unevictable_handler
,
891 * NOTE: do not add new entries to this table unless you have read
892 * Documentation/sysctl/ctl_unnumbered.txt
897 static struct ctl_table vm_table
[] = {
899 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
900 .procname
= "overcommit_memory",
901 .data
= &sysctl_overcommit_memory
,
902 .maxlen
= sizeof(sysctl_overcommit_memory
),
904 .proc_handler
= &proc_dointvec
,
907 .ctl_name
= VM_PANIC_ON_OOM
,
908 .procname
= "panic_on_oom",
909 .data
= &sysctl_panic_on_oom
,
910 .maxlen
= sizeof(sysctl_panic_on_oom
),
912 .proc_handler
= &proc_dointvec
,
915 .ctl_name
= CTL_UNNUMBERED
,
916 .procname
= "oom_kill_allocating_task",
917 .data
= &sysctl_oom_kill_allocating_task
,
918 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
920 .proc_handler
= &proc_dointvec
,
923 .ctl_name
= CTL_UNNUMBERED
,
924 .procname
= "oom_dump_tasks",
925 .data
= &sysctl_oom_dump_tasks
,
926 .maxlen
= sizeof(sysctl_oom_dump_tasks
),
928 .proc_handler
= &proc_dointvec
,
931 .ctl_name
= VM_OVERCOMMIT_RATIO
,
932 .procname
= "overcommit_ratio",
933 .data
= &sysctl_overcommit_ratio
,
934 .maxlen
= sizeof(sysctl_overcommit_ratio
),
936 .proc_handler
= &proc_dointvec
,
939 .ctl_name
= VM_PAGE_CLUSTER
,
940 .procname
= "page-cluster",
941 .data
= &page_cluster
,
942 .maxlen
= sizeof(int),
944 .proc_handler
= &proc_dointvec
,
947 .ctl_name
= VM_DIRTY_BACKGROUND
,
948 .procname
= "dirty_background_ratio",
949 .data
= &dirty_background_ratio
,
950 .maxlen
= sizeof(dirty_background_ratio
),
952 .proc_handler
= &dirty_background_ratio_handler
,
953 .strategy
= &sysctl_intvec
,
955 .extra2
= &one_hundred
,
958 .ctl_name
= CTL_UNNUMBERED
,
959 .procname
= "dirty_background_bytes",
960 .data
= &dirty_background_bytes
,
961 .maxlen
= sizeof(dirty_background_bytes
),
963 .proc_handler
= &dirty_background_bytes_handler
,
964 .strategy
= &sysctl_intvec
,
968 .ctl_name
= VM_DIRTY_RATIO
,
969 .procname
= "dirty_ratio",
970 .data
= &vm_dirty_ratio
,
971 .maxlen
= sizeof(vm_dirty_ratio
),
973 .proc_handler
= &dirty_ratio_handler
,
974 .strategy
= &sysctl_intvec
,
976 .extra2
= &one_hundred
,
979 .ctl_name
= CTL_UNNUMBERED
,
980 .procname
= "dirty_bytes",
981 .data
= &vm_dirty_bytes
,
982 .maxlen
= sizeof(vm_dirty_bytes
),
984 .proc_handler
= &dirty_bytes_handler
,
985 .strategy
= &sysctl_intvec
,
989 .procname
= "dirty_writeback_centisecs",
990 .data
= &dirty_writeback_interval
,
991 .maxlen
= sizeof(dirty_writeback_interval
),
993 .proc_handler
= &dirty_writeback_centisecs_handler
,
996 .procname
= "dirty_expire_centisecs",
997 .data
= &dirty_expire_interval
,
998 .maxlen
= sizeof(dirty_expire_interval
),
1000 .proc_handler
= &proc_dointvec_userhz_jiffies
,
1003 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
1004 .procname
= "nr_pdflush_threads",
1005 .data
= &nr_pdflush_threads
,
1006 .maxlen
= sizeof nr_pdflush_threads
,
1007 .mode
= 0444 /* read-only*/,
1008 .proc_handler
= &proc_dointvec
,
1011 .ctl_name
= VM_SWAPPINESS
,
1012 .procname
= "swappiness",
1013 .data
= &vm_swappiness
,
1014 .maxlen
= sizeof(vm_swappiness
),
1016 .proc_handler
= &proc_dointvec_minmax
,
1017 .strategy
= &sysctl_intvec
,
1019 .extra2
= &one_hundred
,
1021 #ifdef CONFIG_HUGETLB_PAGE
1023 .procname
= "nr_hugepages",
1025 .maxlen
= sizeof(unsigned long),
1027 .proc_handler
= &hugetlb_sysctl_handler
,
1028 .extra1
= (void *)&hugetlb_zero
,
1029 .extra2
= (void *)&hugetlb_infinity
,
1032 .ctl_name
= VM_HUGETLB_GROUP
,
1033 .procname
= "hugetlb_shm_group",
1034 .data
= &sysctl_hugetlb_shm_group
,
1035 .maxlen
= sizeof(gid_t
),
1037 .proc_handler
= &proc_dointvec
,
1040 .ctl_name
= CTL_UNNUMBERED
,
1041 .procname
= "hugepages_treat_as_movable",
1042 .data
= &hugepages_treat_as_movable
,
1043 .maxlen
= sizeof(int),
1045 .proc_handler
= &hugetlb_treat_movable_handler
,
1048 .ctl_name
= CTL_UNNUMBERED
,
1049 .procname
= "nr_overcommit_hugepages",
1051 .maxlen
= sizeof(unsigned long),
1053 .proc_handler
= &hugetlb_overcommit_handler
,
1054 .extra1
= (void *)&hugetlb_zero
,
1055 .extra2
= (void *)&hugetlb_infinity
,
1059 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
1060 .procname
= "lowmem_reserve_ratio",
1061 .data
= &sysctl_lowmem_reserve_ratio
,
1062 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
1064 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
1065 .strategy
= &sysctl_intvec
,
1068 .ctl_name
= VM_DROP_PAGECACHE
,
1069 .procname
= "drop_caches",
1070 .data
= &sysctl_drop_caches
,
1071 .maxlen
= sizeof(int),
1073 .proc_handler
= drop_caches_sysctl_handler
,
1074 .strategy
= &sysctl_intvec
,
1077 .ctl_name
= VM_MIN_FREE_KBYTES
,
1078 .procname
= "min_free_kbytes",
1079 .data
= &min_free_kbytes
,
1080 .maxlen
= sizeof(min_free_kbytes
),
1082 .proc_handler
= &min_free_kbytes_sysctl_handler
,
1083 .strategy
= &sysctl_intvec
,
1087 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
1088 .procname
= "percpu_pagelist_fraction",
1089 .data
= &percpu_pagelist_fraction
,
1090 .maxlen
= sizeof(percpu_pagelist_fraction
),
1092 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
1093 .strategy
= &sysctl_intvec
,
1094 .extra1
= &min_percpu_pagelist_fract
,
1098 .ctl_name
= VM_MAX_MAP_COUNT
,
1099 .procname
= "max_map_count",
1100 .data
= &sysctl_max_map_count
,
1101 .maxlen
= sizeof(sysctl_max_map_count
),
1103 .proc_handler
= &proc_dointvec
1107 .ctl_name
= VM_LAPTOP_MODE
,
1108 .procname
= "laptop_mode",
1109 .data
= &laptop_mode
,
1110 .maxlen
= sizeof(laptop_mode
),
1112 .proc_handler
= &proc_dointvec_jiffies
,
1113 .strategy
= &sysctl_jiffies
,
1116 .ctl_name
= VM_BLOCK_DUMP
,
1117 .procname
= "block_dump",
1118 .data
= &block_dump
,
1119 .maxlen
= sizeof(block_dump
),
1121 .proc_handler
= &proc_dointvec
,
1122 .strategy
= &sysctl_intvec
,
1126 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
1127 .procname
= "vfs_cache_pressure",
1128 .data
= &sysctl_vfs_cache_pressure
,
1129 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
1131 .proc_handler
= &proc_dointvec
,
1132 .strategy
= &sysctl_intvec
,
1135 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1137 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
1138 .procname
= "legacy_va_layout",
1139 .data
= &sysctl_legacy_va_layout
,
1140 .maxlen
= sizeof(sysctl_legacy_va_layout
),
1142 .proc_handler
= &proc_dointvec
,
1143 .strategy
= &sysctl_intvec
,
1149 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
1150 .procname
= "zone_reclaim_mode",
1151 .data
= &zone_reclaim_mode
,
1152 .maxlen
= sizeof(zone_reclaim_mode
),
1154 .proc_handler
= &proc_dointvec
,
1155 .strategy
= &sysctl_intvec
,
1159 .ctl_name
= VM_MIN_UNMAPPED
,
1160 .procname
= "min_unmapped_ratio",
1161 .data
= &sysctl_min_unmapped_ratio
,
1162 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1164 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
1165 .strategy
= &sysctl_intvec
,
1167 .extra2
= &one_hundred
,
1170 .ctl_name
= VM_MIN_SLAB
,
1171 .procname
= "min_slab_ratio",
1172 .data
= &sysctl_min_slab_ratio
,
1173 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1175 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1176 .strategy
= &sysctl_intvec
,
1178 .extra2
= &one_hundred
,
1183 .ctl_name
= CTL_UNNUMBERED
,
1184 .procname
= "stat_interval",
1185 .data
= &sysctl_stat_interval
,
1186 .maxlen
= sizeof(sysctl_stat_interval
),
1188 .proc_handler
= &proc_dointvec_jiffies
,
1189 .strategy
= &sysctl_jiffies
,
1192 #ifdef CONFIG_SECURITY
1194 .ctl_name
= CTL_UNNUMBERED
,
1195 .procname
= "mmap_min_addr",
1196 .data
= &mmap_min_addr
,
1197 .maxlen
= sizeof(unsigned long),
1199 .proc_handler
= &proc_doulongvec_minmax
,
1204 .ctl_name
= CTL_UNNUMBERED
,
1205 .procname
= "numa_zonelist_order",
1206 .data
= &numa_zonelist_order
,
1207 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1209 .proc_handler
= &numa_zonelist_order_handler
,
1210 .strategy
= &sysctl_string
,
1213 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1214 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1216 .ctl_name
= VM_VDSO_ENABLED
,
1217 .procname
= "vdso_enabled",
1218 .data
= &vdso_enabled
,
1219 .maxlen
= sizeof(vdso_enabled
),
1221 .proc_handler
= &proc_dointvec
,
1222 .strategy
= &sysctl_intvec
,
1226 #ifdef CONFIG_HIGHMEM
1228 .ctl_name
= CTL_UNNUMBERED
,
1229 .procname
= "highmem_is_dirtyable",
1230 .data
= &vm_highmem_is_dirtyable
,
1231 .maxlen
= sizeof(vm_highmem_is_dirtyable
),
1233 .proc_handler
= &proc_dointvec_minmax
,
1234 .strategy
= &sysctl_intvec
,
1240 * NOTE: do not add new entries to this table unless you have read
1241 * Documentation/sysctl/ctl_unnumbered.txt
1246 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1247 static struct ctl_table binfmt_misc_table
[] = {
1252 static struct ctl_table fs_table
[] = {
1254 .ctl_name
= FS_NRINODE
,
1255 .procname
= "inode-nr",
1256 .data
= &inodes_stat
,
1257 .maxlen
= 2*sizeof(int),
1259 .proc_handler
= &proc_dointvec
,
1262 .ctl_name
= FS_STATINODE
,
1263 .procname
= "inode-state",
1264 .data
= &inodes_stat
,
1265 .maxlen
= 7*sizeof(int),
1267 .proc_handler
= &proc_dointvec
,
1270 .procname
= "file-nr",
1271 .data
= &files_stat
,
1272 .maxlen
= 3*sizeof(int),
1274 .proc_handler
= &proc_nr_files
,
1277 .ctl_name
= FS_MAXFILE
,
1278 .procname
= "file-max",
1279 .data
= &files_stat
.max_files
,
1280 .maxlen
= sizeof(int),
1282 .proc_handler
= &proc_dointvec
,
1285 .ctl_name
= CTL_UNNUMBERED
,
1286 .procname
= "nr_open",
1287 .data
= &sysctl_nr_open
,
1288 .maxlen
= sizeof(int),
1290 .proc_handler
= &proc_dointvec_minmax
,
1291 .extra1
= &sysctl_nr_open_min
,
1292 .extra2
= &sysctl_nr_open_max
,
1295 .ctl_name
= FS_DENTRY
,
1296 .procname
= "dentry-state",
1297 .data
= &dentry_stat
,
1298 .maxlen
= 6*sizeof(int),
1300 .proc_handler
= &proc_dointvec
,
1303 .ctl_name
= FS_OVERFLOWUID
,
1304 .procname
= "overflowuid",
1305 .data
= &fs_overflowuid
,
1306 .maxlen
= sizeof(int),
1308 .proc_handler
= &proc_dointvec_minmax
,
1309 .strategy
= &sysctl_intvec
,
1310 .extra1
= &minolduid
,
1311 .extra2
= &maxolduid
,
1314 .ctl_name
= FS_OVERFLOWGID
,
1315 .procname
= "overflowgid",
1316 .data
= &fs_overflowgid
,
1317 .maxlen
= sizeof(int),
1319 .proc_handler
= &proc_dointvec_minmax
,
1320 .strategy
= &sysctl_intvec
,
1321 .extra1
= &minolduid
,
1322 .extra2
= &maxolduid
,
1324 #ifdef CONFIG_FILE_LOCKING
1326 .ctl_name
= FS_LEASES
,
1327 .procname
= "leases-enable",
1328 .data
= &leases_enable
,
1329 .maxlen
= sizeof(int),
1331 .proc_handler
= &proc_dointvec
,
1334 #ifdef CONFIG_DNOTIFY
1336 .ctl_name
= FS_DIR_NOTIFY
,
1337 .procname
= "dir-notify-enable",
1338 .data
= &dir_notify_enable
,
1339 .maxlen
= sizeof(int),
1341 .proc_handler
= &proc_dointvec
,
1345 #ifdef CONFIG_FILE_LOCKING
1347 .ctl_name
= FS_LEASE_TIME
,
1348 .procname
= "lease-break-time",
1349 .data
= &lease_break_time
,
1350 .maxlen
= sizeof(int),
1352 .proc_handler
= &proc_dointvec_minmax
,
1353 .strategy
= &sysctl_intvec
,
1360 .procname
= "aio-nr",
1362 .maxlen
= sizeof(aio_nr
),
1364 .proc_handler
= &proc_doulongvec_minmax
,
1367 .procname
= "aio-max-nr",
1368 .data
= &aio_max_nr
,
1369 .maxlen
= sizeof(aio_max_nr
),
1371 .proc_handler
= &proc_doulongvec_minmax
,
1373 #endif /* CONFIG_AIO */
1374 #ifdef CONFIG_INOTIFY_USER
1376 .ctl_name
= FS_INOTIFY
,
1377 .procname
= "inotify",
1379 .child
= inotify_table
,
1384 .procname
= "epoll",
1386 .child
= epoll_table
,
1391 .ctl_name
= KERN_SETUID_DUMPABLE
,
1392 .procname
= "suid_dumpable",
1393 .data
= &suid_dumpable
,
1394 .maxlen
= sizeof(int),
1396 .proc_handler
= &proc_dointvec
,
1398 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1400 .ctl_name
= CTL_UNNUMBERED
,
1401 .procname
= "binfmt_misc",
1403 .child
= binfmt_misc_table
,
1407 * NOTE: do not add new entries to this table unless you have read
1408 * Documentation/sysctl/ctl_unnumbered.txt
1413 static struct ctl_table debug_table
[] = {
1414 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1416 .ctl_name
= CTL_UNNUMBERED
,
1417 .procname
= "exception-trace",
1418 .data
= &show_unhandled_signals
,
1419 .maxlen
= sizeof(int),
1421 .proc_handler
= proc_dointvec
1427 static struct ctl_table dev_table
[] = {
1431 static DEFINE_SPINLOCK(sysctl_lock
);
1433 /* called under sysctl_lock */
1434 static int use_table(struct ctl_table_header
*p
)
1436 if (unlikely(p
->unregistering
))
1442 /* called under sysctl_lock */
1443 static void unuse_table(struct ctl_table_header
*p
)
1446 if (unlikely(p
->unregistering
))
1447 complete(p
->unregistering
);
1450 /* called under sysctl_lock, will reacquire if has to wait */
1451 static void start_unregistering(struct ctl_table_header
*p
)
1454 * if p->used is 0, nobody will ever touch that entry again;
1455 * we'll eliminate all paths to it before dropping sysctl_lock
1457 if (unlikely(p
->used
)) {
1458 struct completion wait
;
1459 init_completion(&wait
);
1460 p
->unregistering
= &wait
;
1461 spin_unlock(&sysctl_lock
);
1462 wait_for_completion(&wait
);
1463 spin_lock(&sysctl_lock
);
1465 /* anything non-NULL; we'll never dereference it */
1466 p
->unregistering
= ERR_PTR(-EINVAL
);
1469 * do not remove from the list until nobody holds it; walking the
1470 * list in do_sysctl() relies on that.
1472 list_del_init(&p
->ctl_entry
);
1475 void sysctl_head_get(struct ctl_table_header
*head
)
1477 spin_lock(&sysctl_lock
);
1479 spin_unlock(&sysctl_lock
);
1482 void sysctl_head_put(struct ctl_table_header
*head
)
1484 spin_lock(&sysctl_lock
);
1487 spin_unlock(&sysctl_lock
);
1490 struct ctl_table_header
*sysctl_head_grab(struct ctl_table_header
*head
)
1494 spin_lock(&sysctl_lock
);
1495 if (!use_table(head
))
1496 head
= ERR_PTR(-ENOENT
);
1497 spin_unlock(&sysctl_lock
);
1501 void sysctl_head_finish(struct ctl_table_header
*head
)
1505 spin_lock(&sysctl_lock
);
1507 spin_unlock(&sysctl_lock
);
1510 static struct ctl_table_set
*
1511 lookup_header_set(struct ctl_table_root
*root
, struct nsproxy
*namespaces
)
1513 struct ctl_table_set
*set
= &root
->default_set
;
1515 set
= root
->lookup(root
, namespaces
);
1519 static struct list_head
*
1520 lookup_header_list(struct ctl_table_root
*root
, struct nsproxy
*namespaces
)
1522 struct ctl_table_set
*set
= lookup_header_set(root
, namespaces
);
1526 struct ctl_table_header
*__sysctl_head_next(struct nsproxy
*namespaces
,
1527 struct ctl_table_header
*prev
)
1529 struct ctl_table_root
*root
;
1530 struct list_head
*header_list
;
1531 struct ctl_table_header
*head
;
1532 struct list_head
*tmp
;
1534 spin_lock(&sysctl_lock
);
1537 tmp
= &prev
->ctl_entry
;
1541 tmp
= &root_table_header
.ctl_entry
;
1543 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1545 if (!use_table(head
))
1547 spin_unlock(&sysctl_lock
);
1552 header_list
= lookup_header_list(root
, namespaces
);
1553 if (tmp
!= header_list
)
1557 root
= list_entry(root
->root_list
.next
,
1558 struct ctl_table_root
, root_list
);
1559 if (root
== &sysctl_table_root
)
1561 header_list
= lookup_header_list(root
, namespaces
);
1562 } while (list_empty(header_list
));
1563 tmp
= header_list
->next
;
1566 spin_unlock(&sysctl_lock
);
1570 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1572 return __sysctl_head_next(current
->nsproxy
, prev
);
1575 void register_sysctl_root(struct ctl_table_root
*root
)
1577 spin_lock(&sysctl_lock
);
1578 list_add_tail(&root
->root_list
, &sysctl_table_root
.root_list
);
1579 spin_unlock(&sysctl_lock
);
1582 #ifdef CONFIG_SYSCTL_SYSCALL
1583 /* Perform the actual read/write of a sysctl table entry. */
1584 static int do_sysctl_strategy(struct ctl_table_root
*root
,
1585 struct ctl_table
*table
,
1586 void __user
*oldval
, size_t __user
*oldlenp
,
1587 void __user
*newval
, size_t newlen
)
1595 if (sysctl_perm(root
, table
, op
))
1598 if (table
->strategy
) {
1599 rc
= table
->strategy(table
, oldval
, oldlenp
, newval
, newlen
);
1606 /* If there is no strategy routine, or if the strategy returns
1607 * zero, proceed with automatic r/w */
1608 if (table
->data
&& table
->maxlen
) {
1609 rc
= sysctl_data(table
, oldval
, oldlenp
, newval
, newlen
);
1616 static int parse_table(int __user
*name
, int nlen
,
1617 void __user
*oldval
, size_t __user
*oldlenp
,
1618 void __user
*newval
, size_t newlen
,
1619 struct ctl_table_root
*root
,
1620 struct ctl_table
*table
)
1626 if (get_user(n
, name
))
1628 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1629 if (!table
->ctl_name
)
1631 if (n
== table
->ctl_name
) {
1634 if (sysctl_perm(root
, table
, MAY_EXEC
))
1638 table
= table
->child
;
1641 error
= do_sysctl_strategy(root
, table
,
1650 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1651 void __user
*newval
, size_t newlen
)
1653 struct ctl_table_header
*head
;
1654 int error
= -ENOTDIR
;
1656 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1660 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1664 for (head
= sysctl_head_next(NULL
); head
;
1665 head
= sysctl_head_next(head
)) {
1666 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1668 head
->root
, head
->ctl_table
);
1669 if (error
!= -ENOTDIR
) {
1670 sysctl_head_finish(head
);
1677 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1679 struct __sysctl_args tmp
;
1682 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1685 error
= deprecated_sysctl_warning(&tmp
);
1690 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1691 tmp
.newval
, tmp
.newlen
);
1696 #endif /* CONFIG_SYSCTL_SYSCALL */
1699 * sysctl_perm does NOT grant the superuser all rights automatically, because
1700 * some sysctl variables are readonly even to root.
1703 static int test_perm(int mode
, int op
)
1705 if (!current_euid())
1707 else if (in_egroup_p(0))
1709 if ((op
& ~mode
& (MAY_READ
|MAY_WRITE
|MAY_EXEC
)) == 0)
1714 int sysctl_perm(struct ctl_table_root
*root
, struct ctl_table
*table
, int op
)
1719 error
= security_sysctl(table
, op
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
));
1723 if (root
->permissions
)
1724 mode
= root
->permissions(root
, current
->nsproxy
, table
);
1728 return test_perm(mode
, op
);
1731 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1733 for (; table
->ctl_name
|| table
->procname
; table
++) {
1734 table
->parent
= parent
;
1736 sysctl_set_parent(table
, table
->child
);
1740 static __init
int sysctl_init(void)
1742 sysctl_set_parent(NULL
, root_table
);
1743 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1746 err
= sysctl_check_table(current
->nsproxy
, root_table
);
1752 core_initcall(sysctl_init
);
1754 static struct ctl_table
*is_branch_in(struct ctl_table
*branch
,
1755 struct ctl_table
*table
)
1757 struct ctl_table
*p
;
1758 const char *s
= branch
->procname
;
1760 /* branch should have named subdirectory as its first element */
1761 if (!s
|| !branch
->child
)
1764 /* ... and nothing else */
1765 if (branch
[1].procname
|| branch
[1].ctl_name
)
1768 /* table should contain subdirectory with the same name */
1769 for (p
= table
; p
->procname
|| p
->ctl_name
; p
++) {
1772 if (p
->procname
&& strcmp(p
->procname
, s
) == 0)
1778 /* see if attaching q to p would be an improvement */
1779 static void try_attach(struct ctl_table_header
*p
, struct ctl_table_header
*q
)
1781 struct ctl_table
*to
= p
->ctl_table
, *by
= q
->ctl_table
;
1782 struct ctl_table
*next
;
1784 int not_in_parent
= !p
->attached_by
;
1786 while ((next
= is_branch_in(by
, to
)) != NULL
) {
1787 if (by
== q
->attached_by
)
1789 if (to
== p
->attached_by
)
1795 if (is_better
&& not_in_parent
) {
1796 q
->attached_by
= by
;
1797 q
->attached_to
= to
;
1803 * __register_sysctl_paths - register a sysctl hierarchy
1804 * @root: List of sysctl headers to register on
1805 * @namespaces: Data to compute which lists of sysctl entries are visible
1806 * @path: The path to the directory the sysctl table is in.
1807 * @table: the top-level table structure
1809 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1810 * array. A completely 0 filled entry terminates the table.
1812 * The members of the &struct ctl_table structure are used as follows:
1814 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1815 * must be unique within that level of sysctl
1817 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1818 * enter a sysctl file
1820 * data - a pointer to data for use by proc_handler
1822 * maxlen - the maximum size in bytes of the data
1824 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1826 * child - a pointer to the child sysctl table if this entry is a directory, or
1829 * proc_handler - the text handler routine (described below)
1831 * strategy - the strategy routine (described below)
1833 * de - for internal use by the sysctl routines
1835 * extra1, extra2 - extra pointers usable by the proc handler routines
1837 * Leaf nodes in the sysctl tree will be represented by a single file
1838 * under /proc; non-leaf nodes will be represented by directories.
1840 * sysctl(2) can automatically manage read and write requests through
1841 * the sysctl table. The data and maxlen fields of the ctl_table
1842 * struct enable minimal validation of the values being written to be
1843 * performed, and the mode field allows minimal authentication.
1845 * More sophisticated management can be enabled by the provision of a
1846 * strategy routine with the table entry. This will be called before
1847 * any automatic read or write of the data is performed.
1849 * The strategy routine may return
1851 * < 0 - Error occurred (error is passed to user process)
1853 * 0 - OK - proceed with automatic read or write.
1855 * > 0 - OK - read or write has been done by the strategy routine, so
1856 * return immediately.
1858 * There must be a proc_handler routine for any terminal nodes
1859 * mirrored under /proc/sys (non-terminals are handled by a built-in
1860 * directory handler). Several default handlers are available to
1861 * cover common cases -
1863 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1864 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1865 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1867 * It is the handler's job to read the input buffer from user memory
1868 * and process it. The handler should return 0 on success.
1870 * This routine returns %NULL on a failure to register, and a pointer
1871 * to the table header on success.
1873 struct ctl_table_header
*__register_sysctl_paths(
1874 struct ctl_table_root
*root
,
1875 struct nsproxy
*namespaces
,
1876 const struct ctl_path
*path
, struct ctl_table
*table
)
1878 struct ctl_table_header
*header
;
1879 struct ctl_table
*new, **prevp
;
1880 unsigned int n
, npath
;
1881 struct ctl_table_set
*set
;
1883 /* Count the path components */
1884 for (npath
= 0; path
[npath
].ctl_name
|| path
[npath
].procname
; ++npath
)
1888 * For each path component, allocate a 2-element ctl_table array.
1889 * The first array element will be filled with the sysctl entry
1890 * for this, the second will be the sentinel (ctl_name == 0).
1892 * We allocate everything in one go so that we don't have to
1893 * worry about freeing additional memory in unregister_sysctl_table.
1895 header
= kzalloc(sizeof(struct ctl_table_header
) +
1896 (2 * npath
* sizeof(struct ctl_table
)), GFP_KERNEL
);
1900 new = (struct ctl_table
*) (header
+ 1);
1902 /* Now connect the dots */
1903 prevp
= &header
->ctl_table
;
1904 for (n
= 0; n
< npath
; ++n
, ++path
) {
1905 /* Copy the procname */
1906 new->procname
= path
->procname
;
1907 new->ctl_name
= path
->ctl_name
;
1911 prevp
= &new->child
;
1916 header
->ctl_table_arg
= table
;
1918 INIT_LIST_HEAD(&header
->ctl_entry
);
1920 header
->unregistering
= NULL
;
1921 header
->root
= root
;
1922 sysctl_set_parent(NULL
, header
->ctl_table
);
1924 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1925 if (sysctl_check_table(namespaces
, header
->ctl_table
)) {
1930 spin_lock(&sysctl_lock
);
1931 header
->set
= lookup_header_set(root
, namespaces
);
1932 header
->attached_by
= header
->ctl_table
;
1933 header
->attached_to
= root_table
;
1934 header
->parent
= &root_table_header
;
1935 for (set
= header
->set
; set
; set
= set
->parent
) {
1936 struct ctl_table_header
*p
;
1937 list_for_each_entry(p
, &set
->list
, ctl_entry
) {
1938 if (p
->unregistering
)
1940 try_attach(p
, header
);
1943 header
->parent
->count
++;
1944 list_add_tail(&header
->ctl_entry
, &header
->set
->list
);
1945 spin_unlock(&sysctl_lock
);
1951 * register_sysctl_table_path - register a sysctl table hierarchy
1952 * @path: The path to the directory the sysctl table is in.
1953 * @table: the top-level table structure
1955 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1956 * array. A completely 0 filled entry terminates the table.
1958 * See __register_sysctl_paths for more details.
1960 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
1961 struct ctl_table
*table
)
1963 return __register_sysctl_paths(&sysctl_table_root
, current
->nsproxy
,
1968 * register_sysctl_table - register a sysctl table hierarchy
1969 * @table: the top-level table structure
1971 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1972 * array. A completely 0 filled entry terminates the table.
1974 * See register_sysctl_paths for more details.
1976 struct ctl_table_header
*register_sysctl_table(struct ctl_table
*table
)
1978 static const struct ctl_path null_path
[] = { {} };
1980 return register_sysctl_paths(null_path
, table
);
1984 * unregister_sysctl_table - unregister a sysctl table hierarchy
1985 * @header: the header returned from register_sysctl_table
1987 * Unregisters the sysctl table and all children. proc entries may not
1988 * actually be removed until they are no longer used by anyone.
1990 void unregister_sysctl_table(struct ctl_table_header
* header
)
1997 spin_lock(&sysctl_lock
);
1998 start_unregistering(header
);
1999 if (!--header
->parent
->count
) {
2001 kfree(header
->parent
);
2003 if (!--header
->count
)
2005 spin_unlock(&sysctl_lock
);
2008 int sysctl_is_seen(struct ctl_table_header
*p
)
2010 struct ctl_table_set
*set
= p
->set
;
2012 spin_lock(&sysctl_lock
);
2013 if (p
->unregistering
)
2015 else if (!set
->is_seen
)
2018 res
= set
->is_seen(set
);
2019 spin_unlock(&sysctl_lock
);
2023 void setup_sysctl_set(struct ctl_table_set
*p
,
2024 struct ctl_table_set
*parent
,
2025 int (*is_seen
)(struct ctl_table_set
*))
2027 INIT_LIST_HEAD(&p
->list
);
2028 p
->parent
= parent
? parent
: &sysctl_table_root
.default_set
;
2029 p
->is_seen
= is_seen
;
2032 #else /* !CONFIG_SYSCTL */
2033 struct ctl_table_header
*register_sysctl_table(struct ctl_table
* table
)
2038 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
2039 struct ctl_table
*table
)
2044 void unregister_sysctl_table(struct ctl_table_header
* table
)
2048 void setup_sysctl_set(struct ctl_table_set
*p
,
2049 struct ctl_table_set
*parent
,
2050 int (*is_seen
)(struct ctl_table_set
*))
2054 void sysctl_head_put(struct ctl_table_header
*head
)
2058 #endif /* CONFIG_SYSCTL */
2064 #ifdef CONFIG_PROC_SYSCTL
2066 static int _proc_do_string(void* data
, int maxlen
, int write
,
2067 struct file
*filp
, void __user
*buffer
,
2068 size_t *lenp
, loff_t
*ppos
)
2074 if (!data
|| !maxlen
|| !*lenp
) {
2082 while (len
< *lenp
) {
2083 if (get_user(c
, p
++))
2085 if (c
== 0 || c
== '\n')
2091 if(copy_from_user(data
, buffer
, len
))
2093 ((char *) data
)[len
] = 0;
2111 if(copy_to_user(buffer
, data
, len
))
2114 if(put_user('\n', ((char __user
*) buffer
) + len
))
2125 * proc_dostring - read a string sysctl
2126 * @table: the sysctl table
2127 * @write: %TRUE if this is a write to the sysctl file
2128 * @filp: the file structure
2129 * @buffer: the user buffer
2130 * @lenp: the size of the user buffer
2131 * @ppos: file position
2133 * Reads/writes a string from/to the user buffer. If the kernel
2134 * buffer provided is not large enough to hold the string, the
2135 * string is truncated. The copied string is %NULL-terminated.
2136 * If the string is being read by the user process, it is copied
2137 * and a newline '\n' is added. It is truncated if the buffer is
2140 * Returns 0 on success.
2142 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2143 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2145 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
2146 buffer
, lenp
, ppos
);
2150 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
2152 int write
, void *data
)
2155 *valp
= *negp
? -*lvalp
: *lvalp
;
2160 *lvalp
= (unsigned long)-val
;
2163 *lvalp
= (unsigned long)val
;
2169 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
2170 int write
, struct file
*filp
, void __user
*buffer
,
2171 size_t *lenp
, loff_t
*ppos
,
2172 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
2173 int write
, void *data
),
2176 #define TMPBUFLEN 21
2177 int *i
, vleft
, first
=1, neg
, val
;
2181 char buf
[TMPBUFLEN
], *p
;
2182 char __user
*s
= buffer
;
2184 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
2185 (*ppos
&& !write
)) {
2190 i
= (int *) tbl_data
;
2191 vleft
= table
->maxlen
/ sizeof(*i
);
2195 conv
= do_proc_dointvec_conv
;
2197 for (; left
&& vleft
--; i
++, first
=0) {
2212 if (len
> sizeof(buf
) - 1)
2213 len
= sizeof(buf
) - 1;
2214 if (copy_from_user(buf
, s
, len
))
2218 if (*p
== '-' && left
> 1) {
2222 if (*p
< '0' || *p
> '9')
2225 lval
= simple_strtoul(p
, &p
, 0);
2228 if ((len
< left
) && *p
&& !isspace(*p
))
2235 if (conv(&neg
, &lval
, i
, 1, data
))
2242 if (conv(&neg
, &lval
, i
, 0, data
))
2245 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
2249 if(copy_to_user(s
, buf
, len
))
2256 if (!write
&& !first
&& left
) {
2257 if(put_user('\n', s
))
2264 if (get_user(c
, s
++))
2279 static int do_proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2280 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
2281 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
2282 int write
, void *data
),
2285 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
2286 buffer
, lenp
, ppos
, conv
, data
);
2290 * proc_dointvec - read a vector of integers
2291 * @table: the sysctl table
2292 * @write: %TRUE if this is a write to the sysctl file
2293 * @filp: the file structure
2294 * @buffer: the user buffer
2295 * @lenp: the size of the user buffer
2296 * @ppos: file position
2298 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2299 * values from/to the user buffer, treated as an ASCII string.
2301 * Returns 0 on success.
2303 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2304 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2306 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2311 * Taint values can only be increased
2312 * This means we can safely use a temporary.
2314 static int proc_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
2315 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2318 unsigned long tmptaint
= get_taint();
2321 if (write
&& !capable(CAP_SYS_ADMIN
))
2326 err
= proc_doulongvec_minmax(&t
, write
, filp
, buffer
, lenp
, ppos
);
2332 * Poor man's atomic or. Not worth adding a primitive
2333 * to everyone's atomic.h for this
2336 for (i
= 0; i
< BITS_PER_LONG
&& tmptaint
>> i
; i
++) {
2337 if ((tmptaint
>> i
) & 1)
2345 struct do_proc_dointvec_minmax_conv_param
{
2350 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
2352 int write
, void *data
)
2354 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
2356 int val
= *negp
? -*lvalp
: *lvalp
;
2357 if ((param
->min
&& *param
->min
> val
) ||
2358 (param
->max
&& *param
->max
< val
))
2365 *lvalp
= (unsigned long)-val
;
2368 *lvalp
= (unsigned long)val
;
2375 * proc_dointvec_minmax - read a vector of integers with min/max values
2376 * @table: the sysctl table
2377 * @write: %TRUE if this is a write to the sysctl file
2378 * @filp: the file structure
2379 * @buffer: the user buffer
2380 * @lenp: the size of the user buffer
2381 * @ppos: file position
2383 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2384 * values from/to the user buffer, treated as an ASCII string.
2386 * This routine will ensure the values are within the range specified by
2387 * table->extra1 (min) and table->extra2 (max).
2389 * Returns 0 on success.
2391 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2392 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2394 struct do_proc_dointvec_minmax_conv_param param
= {
2395 .min
= (int *) table
->extra1
,
2396 .max
= (int *) table
->extra2
,
2398 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2399 do_proc_dointvec_minmax_conv
, ¶m
);
2402 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
2404 void __user
*buffer
,
2405 size_t *lenp
, loff_t
*ppos
,
2406 unsigned long convmul
,
2407 unsigned long convdiv
)
2409 #define TMPBUFLEN 21
2410 unsigned long *i
, *min
, *max
, val
;
2411 int vleft
, first
=1, neg
;
2413 char buf
[TMPBUFLEN
], *p
;
2414 char __user
*s
= buffer
;
2416 if (!data
|| !table
->maxlen
|| !*lenp
||
2417 (*ppos
&& !write
)) {
2422 i
= (unsigned long *) data
;
2423 min
= (unsigned long *) table
->extra1
;
2424 max
= (unsigned long *) table
->extra2
;
2425 vleft
= table
->maxlen
/ sizeof(unsigned long);
2428 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
2443 if (len
> TMPBUFLEN
-1)
2445 if (copy_from_user(buf
, s
, len
))
2449 if (*p
== '-' && left
> 1) {
2453 if (*p
< '0' || *p
> '9')
2455 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2457 if ((len
< left
) && *p
&& !isspace(*p
))
2466 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2473 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2477 if(copy_to_user(s
, buf
, len
))
2484 if (!write
&& !first
&& left
) {
2485 if(put_user('\n', s
))
2492 if (get_user(c
, s
++))
2507 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2509 void __user
*buffer
,
2510 size_t *lenp
, loff_t
*ppos
,
2511 unsigned long convmul
,
2512 unsigned long convdiv
)
2514 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2515 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2519 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2520 * @table: the sysctl table
2521 * @write: %TRUE if this is a write to the sysctl file
2522 * @filp: the file structure
2523 * @buffer: the user buffer
2524 * @lenp: the size of the user buffer
2525 * @ppos: file position
2527 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2528 * values from/to the user buffer, treated as an ASCII string.
2530 * This routine will ensure the values are within the range specified by
2531 * table->extra1 (min) and table->extra2 (max).
2533 * Returns 0 on success.
2535 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2536 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2538 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2542 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2543 * @table: the sysctl table
2544 * @write: %TRUE if this is a write to the sysctl file
2545 * @filp: the file structure
2546 * @buffer: the user buffer
2547 * @lenp: the size of the user buffer
2548 * @ppos: file position
2550 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2551 * values from/to the user buffer, treated as an ASCII string. The values
2552 * are treated as milliseconds, and converted to jiffies when they are stored.
2554 * This routine will ensure the values are within the range specified by
2555 * table->extra1 (min) and table->extra2 (max).
2557 * Returns 0 on success.
2559 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2561 void __user
*buffer
,
2562 size_t *lenp
, loff_t
*ppos
)
2564 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2565 lenp
, ppos
, HZ
, 1000l);
2569 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2571 int write
, void *data
)
2574 if (*lvalp
> LONG_MAX
/ HZ
)
2576 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2582 lval
= (unsigned long)-val
;
2585 lval
= (unsigned long)val
;
2592 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2594 int write
, void *data
)
2597 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2599 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2605 lval
= (unsigned long)-val
;
2608 lval
= (unsigned long)val
;
2610 *lvalp
= jiffies_to_clock_t(lval
);
2615 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2617 int write
, void *data
)
2620 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2626 lval
= (unsigned long)-val
;
2629 lval
= (unsigned long)val
;
2631 *lvalp
= jiffies_to_msecs(lval
);
2637 * proc_dointvec_jiffies - read a vector of integers as seconds
2638 * @table: the sysctl table
2639 * @write: %TRUE if this is a write to the sysctl file
2640 * @filp: the file structure
2641 * @buffer: the user buffer
2642 * @lenp: the size of the user buffer
2643 * @ppos: file position
2645 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2646 * values from/to the user buffer, treated as an ASCII string.
2647 * The values read are assumed to be in seconds, and are converted into
2650 * Returns 0 on success.
2652 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2653 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2655 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2656 do_proc_dointvec_jiffies_conv
,NULL
);
2660 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2661 * @table: the sysctl table
2662 * @write: %TRUE if this is a write to the sysctl file
2663 * @filp: the file structure
2664 * @buffer: the user buffer
2665 * @lenp: the size of the user buffer
2666 * @ppos: pointer to the file position
2668 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2669 * values from/to the user buffer, treated as an ASCII string.
2670 * The values read are assumed to be in 1/USER_HZ seconds, and
2671 * are converted into jiffies.
2673 * Returns 0 on success.
2675 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2676 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2678 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2679 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2683 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2684 * @table: the sysctl table
2685 * @write: %TRUE if this is a write to the sysctl file
2686 * @filp: the file structure
2687 * @buffer: the user buffer
2688 * @lenp: the size of the user buffer
2689 * @ppos: file position
2690 * @ppos: the current position in the file
2692 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2693 * values from/to the user buffer, treated as an ASCII string.
2694 * The values read are assumed to be in 1/1000 seconds, and
2695 * are converted into jiffies.
2697 * Returns 0 on success.
2699 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2700 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2702 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2703 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2706 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
2707 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2709 struct pid
*new_pid
;
2713 tmp
= pid_vnr(cad_pid
);
2715 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2716 lenp
, ppos
, NULL
, NULL
);
2720 new_pid
= find_get_pid(tmp
);
2724 put_pid(xchg(&cad_pid
, new_pid
));
2728 #else /* CONFIG_PROC_FS */
2730 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2731 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2736 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2737 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2742 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2743 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2748 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2749 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2754 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2755 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2760 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2761 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2766 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2767 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2772 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2774 void __user
*buffer
,
2775 size_t *lenp
, loff_t
*ppos
)
2781 #endif /* CONFIG_PROC_FS */
2784 #ifdef CONFIG_SYSCTL_SYSCALL
2786 * General sysctl support routines
2789 /* The generic sysctl data routine (used if no strategy routine supplied) */
2790 int sysctl_data(struct ctl_table
*table
,
2791 void __user
*oldval
, size_t __user
*oldlenp
,
2792 void __user
*newval
, size_t newlen
)
2796 /* Get out of I don't have a variable */
2797 if (!table
->data
|| !table
->maxlen
)
2800 if (oldval
&& oldlenp
) {
2801 if (get_user(len
, oldlenp
))
2804 if (len
> table
->maxlen
)
2805 len
= table
->maxlen
;
2806 if (copy_to_user(oldval
, table
->data
, len
))
2808 if (put_user(len
, oldlenp
))
2813 if (newval
&& newlen
) {
2814 if (newlen
> table
->maxlen
)
2815 newlen
= table
->maxlen
;
2817 if (copy_from_user(table
->data
, newval
, newlen
))
2823 /* The generic string strategy routine: */
2824 int sysctl_string(struct ctl_table
*table
,
2825 void __user
*oldval
, size_t __user
*oldlenp
,
2826 void __user
*newval
, size_t newlen
)
2828 if (!table
->data
|| !table
->maxlen
)
2831 if (oldval
&& oldlenp
) {
2833 if (get_user(bufsize
, oldlenp
))
2836 size_t len
= strlen(table
->data
), copied
;
2838 /* This shouldn't trigger for a well-formed sysctl */
2839 if (len
> table
->maxlen
)
2840 len
= table
->maxlen
;
2842 /* Copy up to a max of bufsize-1 bytes of the string */
2843 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2845 if (copy_to_user(oldval
, table
->data
, copied
) ||
2846 put_user(0, (char __user
*)(oldval
+ copied
)))
2848 if (put_user(len
, oldlenp
))
2852 if (newval
&& newlen
) {
2853 size_t len
= newlen
;
2854 if (len
> table
->maxlen
)
2855 len
= table
->maxlen
;
2856 if(copy_from_user(table
->data
, newval
, len
))
2858 if (len
== table
->maxlen
)
2860 ((char *) table
->data
)[len
] = 0;
2866 * This function makes sure that all of the integers in the vector
2867 * are between the minimum and maximum values given in the arrays
2868 * table->extra1 and table->extra2, respectively.
2870 int sysctl_intvec(struct ctl_table
*table
,
2871 void __user
*oldval
, size_t __user
*oldlenp
,
2872 void __user
*newval
, size_t newlen
)
2875 if (newval
&& newlen
) {
2876 int __user
*vec
= (int __user
*) newval
;
2877 int *min
= (int *) table
->extra1
;
2878 int *max
= (int *) table
->extra2
;
2882 if (newlen
% sizeof(int) != 0)
2885 if (!table
->extra1
&& !table
->extra2
)
2888 if (newlen
> table
->maxlen
)
2889 newlen
= table
->maxlen
;
2890 length
= newlen
/ sizeof(int);
2892 for (i
= 0; i
< length
; i
++) {
2894 if (get_user(value
, vec
+ i
))
2896 if (min
&& value
< min
[i
])
2898 if (max
&& value
> max
[i
])
2905 /* Strategy function to convert jiffies to seconds */
2906 int sysctl_jiffies(struct ctl_table
*table
,
2907 void __user
*oldval
, size_t __user
*oldlenp
,
2908 void __user
*newval
, size_t newlen
)
2910 if (oldval
&& oldlenp
) {
2913 if (get_user(olen
, oldlenp
))
2918 if (olen
< sizeof(int))
2921 val
= *(int *)(table
->data
) / HZ
;
2922 if (put_user(val
, (int __user
*)oldval
))
2924 if (put_user(sizeof(int), oldlenp
))
2928 if (newval
&& newlen
) {
2930 if (newlen
!= sizeof(int))
2932 if (get_user(new, (int __user
*)newval
))
2934 *(int *)(table
->data
) = new*HZ
;
2939 /* Strategy function to convert jiffies to seconds */
2940 int sysctl_ms_jiffies(struct ctl_table
*table
,
2941 void __user
*oldval
, size_t __user
*oldlenp
,
2942 void __user
*newval
, size_t newlen
)
2944 if (oldval
&& oldlenp
) {
2947 if (get_user(olen
, oldlenp
))
2952 if (olen
< sizeof(int))
2955 val
= jiffies_to_msecs(*(int *)(table
->data
));
2956 if (put_user(val
, (int __user
*)oldval
))
2958 if (put_user(sizeof(int), oldlenp
))
2962 if (newval
&& newlen
) {
2964 if (newlen
!= sizeof(int))
2966 if (get_user(new, (int __user
*)newval
))
2968 *(int *)(table
->data
) = msecs_to_jiffies(new);
2975 #else /* CONFIG_SYSCTL_SYSCALL */
2978 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2980 struct __sysctl_args tmp
;
2983 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2986 error
= deprecated_sysctl_warning(&tmp
);
2988 /* If no error reading the parameters then just -ENOSYS ... */
2995 int sysctl_data(struct ctl_table
*table
,
2996 void __user
*oldval
, size_t __user
*oldlenp
,
2997 void __user
*newval
, size_t newlen
)
3002 int sysctl_string(struct ctl_table
*table
,
3003 void __user
*oldval
, size_t __user
*oldlenp
,
3004 void __user
*newval
, size_t newlen
)
3009 int sysctl_intvec(struct ctl_table
*table
,
3010 void __user
*oldval
, size_t __user
*oldlenp
,
3011 void __user
*newval
, size_t newlen
)
3016 int sysctl_jiffies(struct ctl_table
*table
,
3017 void __user
*oldval
, size_t __user
*oldlenp
,
3018 void __user
*newval
, size_t newlen
)
3023 int sysctl_ms_jiffies(struct ctl_table
*table
,
3024 void __user
*oldval
, size_t __user
*oldlenp
,
3025 void __user
*newval
, size_t newlen
)
3030 #endif /* CONFIG_SYSCTL_SYSCALL */
3032 static int deprecated_sysctl_warning(struct __sysctl_args
*args
)
3034 static int msg_count
;
3035 int name
[CTL_MAXNAME
];
3038 /* Check args->nlen. */
3039 if (args
->nlen
< 0 || args
->nlen
> CTL_MAXNAME
)
3042 /* Read in the sysctl name for better debug message logging */
3043 for (i
= 0; i
< args
->nlen
; i
++)
3044 if (get_user(name
[i
], args
->name
+ i
))
3047 /* Ignore accesses to kernel.version */
3048 if ((args
->nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
3051 if (msg_count
< 5) {
3054 "warning: process `%s' used the deprecated sysctl "
3055 "system call with ", current
->comm
);
3056 for (i
= 0; i
< args
->nlen
; i
++)
3057 printk("%d.", name
[i
]);
3064 * No sense putting this after each symbol definition, twice,
3065 * exception granted :-)
3067 EXPORT_SYMBOL(proc_dointvec
);
3068 EXPORT_SYMBOL(proc_dointvec_jiffies
);
3069 EXPORT_SYMBOL(proc_dointvec_minmax
);
3070 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
3071 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
3072 EXPORT_SYMBOL(proc_dostring
);
3073 EXPORT_SYMBOL(proc_doulongvec_minmax
);
3074 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
3075 EXPORT_SYMBOL(register_sysctl_table
);
3076 EXPORT_SYMBOL(register_sysctl_paths
);
3077 EXPORT_SYMBOL(sysctl_intvec
);
3078 EXPORT_SYMBOL(sysctl_jiffies
);
3079 EXPORT_SYMBOL(sysctl_ms_jiffies
);
3080 EXPORT_SYMBOL(sysctl_string
);
3081 EXPORT_SYMBOL(sysctl_data
);
3082 EXPORT_SYMBOL(unregister_sysctl_table
);