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
;
86 extern int sysctl_nr_trim_pages
;
88 #ifdef CONFIG_RCU_TORTURE_TEST
89 extern int rcutorture_runnable
;
90 #endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
92 /* Constants used for minimum and maximum */
93 #ifdef CONFIG_DETECT_SOFTLOCKUP
94 static int sixty
= 60;
95 static int neg_one
= -1;
98 #if defined(CONFIG_MMU) && defined(CONFIG_FILE_LOCKING)
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 #include <asm/system.h>
124 #ifdef CONFIG_SPARC64
125 extern int sysctl_tsb_ratio
;
129 extern int pwrsw_enabled
;
130 extern int unaligned_enabled
;
134 #ifdef CONFIG_MATHEMU
135 extern int sysctl_ieee_emulation_warnings
;
137 extern int sysctl_userprocess_debug
;
138 extern int spin_retry
;
141 #ifdef CONFIG_BSD_PROCESS_ACCT
142 extern int acct_parm
[];
146 extern int no_unaligned_warning
;
147 extern int unaligned_dump_stack
;
150 #ifdef CONFIG_RT_MUTEXES
151 extern int max_lock_depth
;
154 #ifdef CONFIG_PROC_SYSCTL
155 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
156 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
157 static int proc_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
158 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
161 static struct ctl_table root_table
[];
162 static struct ctl_table_root sysctl_table_root
;
163 static struct ctl_table_header root_table_header
= {
165 .ctl_table
= root_table
,
166 .ctl_entry
= LIST_HEAD_INIT(sysctl_table_root
.default_set
.list
),
167 .root
= &sysctl_table_root
,
168 .set
= &sysctl_table_root
.default_set
,
170 static struct ctl_table_root sysctl_table_root
= {
171 .root_list
= LIST_HEAD_INIT(sysctl_table_root
.root_list
),
172 .default_set
.list
= LIST_HEAD_INIT(root_table_header
.ctl_entry
),
175 static struct ctl_table kern_table
[];
176 static struct ctl_table vm_table
[];
177 static struct ctl_table fs_table
[];
178 static struct ctl_table debug_table
[];
179 static struct ctl_table dev_table
[];
180 extern struct ctl_table random_table
[];
181 #ifdef CONFIG_INOTIFY_USER
182 extern struct ctl_table inotify_table
[];
185 extern struct ctl_table epoll_table
[];
188 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
189 int sysctl_legacy_va_layout
;
192 extern int prove_locking
;
193 extern int lock_stat
;
195 /* The default sysctl tables: */
197 static struct ctl_table root_table
[] = {
199 .ctl_name
= CTL_KERN
,
200 .procname
= "kernel",
217 .ctl_name
= CTL_DEBUG
,
220 .child
= debug_table
,
229 * NOTE: do not add new entries to this table unless you have read
230 * Documentation/sysctl/ctl_unnumbered.txt
235 #ifdef CONFIG_SCHED_DEBUG
236 static int min_sched_granularity_ns
= 100000; /* 100 usecs */
237 static int max_sched_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
238 static int min_wakeup_granularity_ns
; /* 0 usecs */
239 static int max_wakeup_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
242 static struct ctl_table kern_table
[] = {
243 #ifdef CONFIG_SCHED_DEBUG
245 .ctl_name
= CTL_UNNUMBERED
,
246 .procname
= "sched_min_granularity_ns",
247 .data
= &sysctl_sched_min_granularity
,
248 .maxlen
= sizeof(unsigned int),
250 .proc_handler
= &sched_nr_latency_handler
,
251 .strategy
= &sysctl_intvec
,
252 .extra1
= &min_sched_granularity_ns
,
253 .extra2
= &max_sched_granularity_ns
,
256 .ctl_name
= CTL_UNNUMBERED
,
257 .procname
= "sched_latency_ns",
258 .data
= &sysctl_sched_latency
,
259 .maxlen
= sizeof(unsigned int),
261 .proc_handler
= &sched_nr_latency_handler
,
262 .strategy
= &sysctl_intvec
,
263 .extra1
= &min_sched_granularity_ns
,
264 .extra2
= &max_sched_granularity_ns
,
267 .ctl_name
= CTL_UNNUMBERED
,
268 .procname
= "sched_wakeup_granularity_ns",
269 .data
= &sysctl_sched_wakeup_granularity
,
270 .maxlen
= sizeof(unsigned int),
272 .proc_handler
= &proc_dointvec_minmax
,
273 .strategy
= &sysctl_intvec
,
274 .extra1
= &min_wakeup_granularity_ns
,
275 .extra2
= &max_wakeup_granularity_ns
,
278 .ctl_name
= CTL_UNNUMBERED
,
279 .procname
= "sched_shares_ratelimit",
280 .data
= &sysctl_sched_shares_ratelimit
,
281 .maxlen
= sizeof(unsigned int),
283 .proc_handler
= &proc_dointvec
,
286 .ctl_name
= CTL_UNNUMBERED
,
287 .procname
= "sched_shares_thresh",
288 .data
= &sysctl_sched_shares_thresh
,
289 .maxlen
= sizeof(unsigned int),
291 .proc_handler
= &proc_dointvec_minmax
,
292 .strategy
= &sysctl_intvec
,
296 .ctl_name
= CTL_UNNUMBERED
,
297 .procname
= "sched_child_runs_first",
298 .data
= &sysctl_sched_child_runs_first
,
299 .maxlen
= sizeof(unsigned int),
301 .proc_handler
= &proc_dointvec
,
304 .ctl_name
= CTL_UNNUMBERED
,
305 .procname
= "sched_features",
306 .data
= &sysctl_sched_features
,
307 .maxlen
= sizeof(unsigned int),
309 .proc_handler
= &proc_dointvec
,
312 .ctl_name
= CTL_UNNUMBERED
,
313 .procname
= "sched_migration_cost",
314 .data
= &sysctl_sched_migration_cost
,
315 .maxlen
= sizeof(unsigned int),
317 .proc_handler
= &proc_dointvec
,
320 .ctl_name
= CTL_UNNUMBERED
,
321 .procname
= "sched_nr_migrate",
322 .data
= &sysctl_sched_nr_migrate
,
323 .maxlen
= sizeof(unsigned int),
325 .proc_handler
= &proc_dointvec
,
329 .ctl_name
= CTL_UNNUMBERED
,
330 .procname
= "sched_rt_period_us",
331 .data
= &sysctl_sched_rt_period
,
332 .maxlen
= sizeof(unsigned int),
334 .proc_handler
= &sched_rt_handler
,
337 .ctl_name
= CTL_UNNUMBERED
,
338 .procname
= "sched_rt_runtime_us",
339 .data
= &sysctl_sched_rt_runtime
,
340 .maxlen
= sizeof(int),
342 .proc_handler
= &sched_rt_handler
,
345 .ctl_name
= CTL_UNNUMBERED
,
346 .procname
= "sched_compat_yield",
347 .data
= &sysctl_sched_compat_yield
,
348 .maxlen
= sizeof(unsigned int),
350 .proc_handler
= &proc_dointvec
,
352 #ifdef CONFIG_PROVE_LOCKING
354 .ctl_name
= CTL_UNNUMBERED
,
355 .procname
= "prove_locking",
356 .data
= &prove_locking
,
357 .maxlen
= sizeof(int),
359 .proc_handler
= &proc_dointvec
,
362 #ifdef CONFIG_LOCK_STAT
364 .ctl_name
= CTL_UNNUMBERED
,
365 .procname
= "lock_stat",
367 .maxlen
= sizeof(int),
369 .proc_handler
= &proc_dointvec
,
373 .ctl_name
= KERN_PANIC
,
375 .data
= &panic_timeout
,
376 .maxlen
= sizeof(int),
378 .proc_handler
= &proc_dointvec
,
381 .ctl_name
= KERN_CORE_USES_PID
,
382 .procname
= "core_uses_pid",
383 .data
= &core_uses_pid
,
384 .maxlen
= sizeof(int),
386 .proc_handler
= &proc_dointvec
,
389 .ctl_name
= KERN_CORE_PATTERN
,
390 .procname
= "core_pattern",
391 .data
= core_pattern
,
392 .maxlen
= CORENAME_MAX_SIZE
,
394 .proc_handler
= &proc_dostring
,
395 .strategy
= &sysctl_string
,
397 #ifdef CONFIG_PROC_SYSCTL
399 .procname
= "tainted",
400 .maxlen
= sizeof(long),
402 .proc_handler
= &proc_taint
,
405 #ifdef CONFIG_LATENCYTOP
407 .procname
= "latencytop",
408 .data
= &latencytop_enabled
,
409 .maxlen
= sizeof(int),
411 .proc_handler
= &proc_dointvec
,
414 #ifdef CONFIG_BLK_DEV_INITRD
416 .ctl_name
= KERN_REALROOTDEV
,
417 .procname
= "real-root-dev",
418 .data
= &real_root_dev
,
419 .maxlen
= sizeof(int),
421 .proc_handler
= &proc_dointvec
,
425 .ctl_name
= CTL_UNNUMBERED
,
426 .procname
= "print-fatal-signals",
427 .data
= &print_fatal_signals
,
428 .maxlen
= sizeof(int),
430 .proc_handler
= &proc_dointvec
,
434 .ctl_name
= KERN_SPARC_REBOOT
,
435 .procname
= "reboot-cmd",
436 .data
= reboot_command
,
439 .proc_handler
= &proc_dostring
,
440 .strategy
= &sysctl_string
,
443 .ctl_name
= KERN_SPARC_STOP_A
,
444 .procname
= "stop-a",
445 .data
= &stop_a_enabled
,
446 .maxlen
= sizeof (int),
448 .proc_handler
= &proc_dointvec
,
451 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
452 .procname
= "scons-poweroff",
453 .data
= &scons_pwroff
,
454 .maxlen
= sizeof (int),
456 .proc_handler
= &proc_dointvec
,
459 #ifdef CONFIG_SPARC64
461 .ctl_name
= CTL_UNNUMBERED
,
462 .procname
= "tsb-ratio",
463 .data
= &sysctl_tsb_ratio
,
464 .maxlen
= sizeof (int),
466 .proc_handler
= &proc_dointvec
,
471 .ctl_name
= KERN_HPPA_PWRSW
,
472 .procname
= "soft-power",
473 .data
= &pwrsw_enabled
,
474 .maxlen
= sizeof (int),
476 .proc_handler
= &proc_dointvec
,
479 .ctl_name
= KERN_HPPA_UNALIGNED
,
480 .procname
= "unaligned-trap",
481 .data
= &unaligned_enabled
,
482 .maxlen
= sizeof (int),
484 .proc_handler
= &proc_dointvec
,
488 .ctl_name
= KERN_CTLALTDEL
,
489 .procname
= "ctrl-alt-del",
491 .maxlen
= sizeof(int),
493 .proc_handler
= &proc_dointvec
,
495 #ifdef CONFIG_FUNCTION_TRACER
497 .ctl_name
= CTL_UNNUMBERED
,
498 .procname
= "ftrace_enabled",
499 .data
= &ftrace_enabled
,
500 .maxlen
= sizeof(int),
502 .proc_handler
= &ftrace_enable_sysctl
,
505 #ifdef CONFIG_STACK_TRACER
507 .ctl_name
= CTL_UNNUMBERED
,
508 .procname
= "stack_tracer_enabled",
509 .data
= &stack_tracer_enabled
,
510 .maxlen
= sizeof(int),
512 .proc_handler
= &stack_trace_sysctl
,
515 #ifdef CONFIG_TRACING
517 .ctl_name
= CTL_UNNUMBERED
,
518 .procname
= "ftrace_dump_on_oops",
519 .data
= &ftrace_dump_on_oops
,
520 .maxlen
= sizeof(int),
522 .proc_handler
= &proc_dointvec
,
525 #ifdef CONFIG_MODULES
527 .ctl_name
= KERN_MODPROBE
,
528 .procname
= "modprobe",
529 .data
= &modprobe_path
,
530 .maxlen
= KMOD_PATH_LEN
,
532 .proc_handler
= &proc_dostring
,
533 .strategy
= &sysctl_string
,
536 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
538 .ctl_name
= KERN_HOTPLUG
,
539 .procname
= "hotplug",
540 .data
= &uevent_helper
,
541 .maxlen
= UEVENT_HELPER_PATH_LEN
,
543 .proc_handler
= &proc_dostring
,
544 .strategy
= &sysctl_string
,
547 #ifdef CONFIG_CHR_DEV_SG
549 .ctl_name
= KERN_SG_BIG_BUFF
,
550 .procname
= "sg-big-buff",
551 .data
= &sg_big_buff
,
552 .maxlen
= sizeof (int),
554 .proc_handler
= &proc_dointvec
,
557 #ifdef CONFIG_BSD_PROCESS_ACCT
559 .ctl_name
= KERN_ACCT
,
562 .maxlen
= 3*sizeof(int),
564 .proc_handler
= &proc_dointvec
,
567 #ifdef CONFIG_MAGIC_SYSRQ
569 .ctl_name
= KERN_SYSRQ
,
571 .data
= &__sysrq_enabled
,
572 .maxlen
= sizeof (int),
574 .proc_handler
= &proc_dointvec
,
577 #ifdef CONFIG_PROC_SYSCTL
579 .procname
= "cad_pid",
581 .maxlen
= sizeof (int),
583 .proc_handler
= &proc_do_cad_pid
,
587 .ctl_name
= KERN_MAX_THREADS
,
588 .procname
= "threads-max",
589 .data
= &max_threads
,
590 .maxlen
= sizeof(int),
592 .proc_handler
= &proc_dointvec
,
595 .ctl_name
= KERN_RANDOM
,
596 .procname
= "random",
598 .child
= random_table
,
601 .ctl_name
= KERN_OVERFLOWUID
,
602 .procname
= "overflowuid",
603 .data
= &overflowuid
,
604 .maxlen
= sizeof(int),
606 .proc_handler
= &proc_dointvec_minmax
,
607 .strategy
= &sysctl_intvec
,
608 .extra1
= &minolduid
,
609 .extra2
= &maxolduid
,
612 .ctl_name
= KERN_OVERFLOWGID
,
613 .procname
= "overflowgid",
614 .data
= &overflowgid
,
615 .maxlen
= sizeof(int),
617 .proc_handler
= &proc_dointvec_minmax
,
618 .strategy
= &sysctl_intvec
,
619 .extra1
= &minolduid
,
620 .extra2
= &maxolduid
,
623 #ifdef CONFIG_MATHEMU
625 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
626 .procname
= "ieee_emulation_warnings",
627 .data
= &sysctl_ieee_emulation_warnings
,
628 .maxlen
= sizeof(int),
630 .proc_handler
= &proc_dointvec
,
634 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
635 .procname
= "userprocess_debug",
636 .data
= &sysctl_userprocess_debug
,
637 .maxlen
= sizeof(int),
639 .proc_handler
= &proc_dointvec
,
643 .ctl_name
= KERN_PIDMAX
,
644 .procname
= "pid_max",
646 .maxlen
= sizeof (int),
648 .proc_handler
= &proc_dointvec_minmax
,
649 .strategy
= sysctl_intvec
,
650 .extra1
= &pid_max_min
,
651 .extra2
= &pid_max_max
,
654 .ctl_name
= KERN_PANIC_ON_OOPS
,
655 .procname
= "panic_on_oops",
656 .data
= &panic_on_oops
,
657 .maxlen
= sizeof(int),
659 .proc_handler
= &proc_dointvec
,
661 #if defined CONFIG_PRINTK
663 .ctl_name
= KERN_PRINTK
,
664 .procname
= "printk",
665 .data
= &console_loglevel
,
666 .maxlen
= 4*sizeof(int),
668 .proc_handler
= &proc_dointvec
,
671 .ctl_name
= KERN_PRINTK_RATELIMIT
,
672 .procname
= "printk_ratelimit",
673 .data
= &printk_ratelimit_state
.interval
,
674 .maxlen
= sizeof(int),
676 .proc_handler
= &proc_dointvec_jiffies
,
677 .strategy
= &sysctl_jiffies
,
680 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
681 .procname
= "printk_ratelimit_burst",
682 .data
= &printk_ratelimit_state
.burst
,
683 .maxlen
= sizeof(int),
685 .proc_handler
= &proc_dointvec
,
689 .ctl_name
= KERN_NGROUPS_MAX
,
690 .procname
= "ngroups_max",
691 .data
= &ngroups_max
,
692 .maxlen
= sizeof (int),
694 .proc_handler
= &proc_dointvec
,
696 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
698 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
699 .procname
= "unknown_nmi_panic",
700 .data
= &unknown_nmi_panic
,
701 .maxlen
= sizeof (int),
703 .proc_handler
= &proc_dointvec
,
706 .procname
= "nmi_watchdog",
707 .data
= &nmi_watchdog_enabled
,
708 .maxlen
= sizeof (int),
710 .proc_handler
= &proc_nmi_enabled
,
713 #if defined(CONFIG_X86)
715 .ctl_name
= KERN_PANIC_ON_NMI
,
716 .procname
= "panic_on_unrecovered_nmi",
717 .data
= &panic_on_unrecovered_nmi
,
718 .maxlen
= sizeof(int),
720 .proc_handler
= &proc_dointvec
,
723 .ctl_name
= KERN_BOOTLOADER_TYPE
,
724 .procname
= "bootloader_type",
725 .data
= &bootloader_type
,
726 .maxlen
= sizeof (int),
728 .proc_handler
= &proc_dointvec
,
731 .ctl_name
= CTL_UNNUMBERED
,
732 .procname
= "kstack_depth_to_print",
733 .data
= &kstack_depth_to_print
,
734 .maxlen
= sizeof(int),
736 .proc_handler
= &proc_dointvec
,
739 .ctl_name
= CTL_UNNUMBERED
,
740 .procname
= "io_delay_type",
741 .data
= &io_delay_type
,
742 .maxlen
= sizeof(int),
744 .proc_handler
= &proc_dointvec
,
747 #if defined(CONFIG_MMU)
749 .ctl_name
= KERN_RANDOMIZE
,
750 .procname
= "randomize_va_space",
751 .data
= &randomize_va_space
,
752 .maxlen
= sizeof(int),
754 .proc_handler
= &proc_dointvec
,
757 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
759 .ctl_name
= KERN_SPIN_RETRY
,
760 .procname
= "spin_retry",
762 .maxlen
= sizeof (int),
764 .proc_handler
= &proc_dointvec
,
767 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
769 .procname
= "acpi_video_flags",
770 .data
= &acpi_realmode_flags
,
771 .maxlen
= sizeof (unsigned long),
773 .proc_handler
= &proc_doulongvec_minmax
,
778 .ctl_name
= KERN_IA64_UNALIGNED
,
779 .procname
= "ignore-unaligned-usertrap",
780 .data
= &no_unaligned_warning
,
781 .maxlen
= sizeof (int),
783 .proc_handler
= &proc_dointvec
,
786 .ctl_name
= CTL_UNNUMBERED
,
787 .procname
= "unaligned-dump-stack",
788 .data
= &unaligned_dump_stack
,
789 .maxlen
= sizeof (int),
791 .proc_handler
= &proc_dointvec
,
794 #ifdef CONFIG_DETECT_SOFTLOCKUP
796 .ctl_name
= CTL_UNNUMBERED
,
797 .procname
= "softlockup_panic",
798 .data
= &softlockup_panic
,
799 .maxlen
= sizeof(int),
801 .proc_handler
= &proc_dointvec_minmax
,
802 .strategy
= &sysctl_intvec
,
807 .ctl_name
= CTL_UNNUMBERED
,
808 .procname
= "softlockup_thresh",
809 .data
= &softlockup_thresh
,
810 .maxlen
= sizeof(int),
812 .proc_handler
= &proc_dointvec_minmax
,
813 .strategy
= &sysctl_intvec
,
818 .ctl_name
= CTL_UNNUMBERED
,
819 .procname
= "hung_task_check_count",
820 .data
= &sysctl_hung_task_check_count
,
821 .maxlen
= sizeof(unsigned long),
823 .proc_handler
= &proc_doulongvec_minmax
,
824 .strategy
= &sysctl_intvec
,
827 .ctl_name
= CTL_UNNUMBERED
,
828 .procname
= "hung_task_timeout_secs",
829 .data
= &sysctl_hung_task_timeout_secs
,
830 .maxlen
= sizeof(unsigned long),
832 .proc_handler
= &proc_doulongvec_minmax
,
833 .strategy
= &sysctl_intvec
,
836 .ctl_name
= CTL_UNNUMBERED
,
837 .procname
= "hung_task_warnings",
838 .data
= &sysctl_hung_task_warnings
,
839 .maxlen
= sizeof(unsigned long),
841 .proc_handler
= &proc_doulongvec_minmax
,
842 .strategy
= &sysctl_intvec
,
847 .ctl_name
= KERN_COMPAT_LOG
,
848 .procname
= "compat-log",
850 .maxlen
= sizeof (int),
852 .proc_handler
= &proc_dointvec
,
855 #ifdef CONFIG_RT_MUTEXES
857 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
858 .procname
= "max_lock_depth",
859 .data
= &max_lock_depth
,
860 .maxlen
= sizeof(int),
862 .proc_handler
= &proc_dointvec
,
866 .ctl_name
= CTL_UNNUMBERED
,
867 .procname
= "poweroff_cmd",
868 .data
= &poweroff_cmd
,
869 .maxlen
= POWEROFF_CMD_PATH_LEN
,
871 .proc_handler
= &proc_dostring
,
872 .strategy
= &sysctl_string
,
876 .ctl_name
= CTL_UNNUMBERED
,
879 .child
= key_sysctls
,
882 #ifdef CONFIG_RCU_TORTURE_TEST
884 .ctl_name
= CTL_UNNUMBERED
,
885 .procname
= "rcutorture_runnable",
886 .data
= &rcutorture_runnable
,
887 .maxlen
= sizeof(int),
889 .proc_handler
= &proc_dointvec
,
892 #ifdef CONFIG_UNEVICTABLE_LRU
894 .ctl_name
= CTL_UNNUMBERED
,
895 .procname
= "scan_unevictable_pages",
896 .data
= &scan_unevictable_pages
,
897 .maxlen
= sizeof(scan_unevictable_pages
),
899 .proc_handler
= &scan_unevictable_handler
,
903 * NOTE: do not add new entries to this table unless you have read
904 * Documentation/sysctl/ctl_unnumbered.txt
909 static struct ctl_table vm_table
[] = {
911 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
912 .procname
= "overcommit_memory",
913 .data
= &sysctl_overcommit_memory
,
914 .maxlen
= sizeof(sysctl_overcommit_memory
),
916 .proc_handler
= &proc_dointvec
,
919 .ctl_name
= VM_PANIC_ON_OOM
,
920 .procname
= "panic_on_oom",
921 .data
= &sysctl_panic_on_oom
,
922 .maxlen
= sizeof(sysctl_panic_on_oom
),
924 .proc_handler
= &proc_dointvec
,
927 .ctl_name
= CTL_UNNUMBERED
,
928 .procname
= "oom_kill_allocating_task",
929 .data
= &sysctl_oom_kill_allocating_task
,
930 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
932 .proc_handler
= &proc_dointvec
,
935 .ctl_name
= CTL_UNNUMBERED
,
936 .procname
= "oom_dump_tasks",
937 .data
= &sysctl_oom_dump_tasks
,
938 .maxlen
= sizeof(sysctl_oom_dump_tasks
),
940 .proc_handler
= &proc_dointvec
,
943 .ctl_name
= VM_OVERCOMMIT_RATIO
,
944 .procname
= "overcommit_ratio",
945 .data
= &sysctl_overcommit_ratio
,
946 .maxlen
= sizeof(sysctl_overcommit_ratio
),
948 .proc_handler
= &proc_dointvec
,
951 .ctl_name
= VM_PAGE_CLUSTER
,
952 .procname
= "page-cluster",
953 .data
= &page_cluster
,
954 .maxlen
= sizeof(int),
956 .proc_handler
= &proc_dointvec
,
959 .ctl_name
= VM_DIRTY_BACKGROUND
,
960 .procname
= "dirty_background_ratio",
961 .data
= &dirty_background_ratio
,
962 .maxlen
= sizeof(dirty_background_ratio
),
964 .proc_handler
= &dirty_background_ratio_handler
,
965 .strategy
= &sysctl_intvec
,
967 .extra2
= &one_hundred
,
970 .ctl_name
= CTL_UNNUMBERED
,
971 .procname
= "dirty_background_bytes",
972 .data
= &dirty_background_bytes
,
973 .maxlen
= sizeof(dirty_background_bytes
),
975 .proc_handler
= &dirty_background_bytes_handler
,
976 .strategy
= &sysctl_intvec
,
980 .ctl_name
= VM_DIRTY_RATIO
,
981 .procname
= "dirty_ratio",
982 .data
= &vm_dirty_ratio
,
983 .maxlen
= sizeof(vm_dirty_ratio
),
985 .proc_handler
= &dirty_ratio_handler
,
986 .strategy
= &sysctl_intvec
,
988 .extra2
= &one_hundred
,
991 .ctl_name
= CTL_UNNUMBERED
,
992 .procname
= "dirty_bytes",
993 .data
= &vm_dirty_bytes
,
994 .maxlen
= sizeof(vm_dirty_bytes
),
996 .proc_handler
= &dirty_bytes_handler
,
997 .strategy
= &sysctl_intvec
,
1001 .procname
= "dirty_writeback_centisecs",
1002 .data
= &dirty_writeback_interval
,
1003 .maxlen
= sizeof(dirty_writeback_interval
),
1005 .proc_handler
= &dirty_writeback_centisecs_handler
,
1008 .procname
= "dirty_expire_centisecs",
1009 .data
= &dirty_expire_interval
,
1010 .maxlen
= sizeof(dirty_expire_interval
),
1012 .proc_handler
= &proc_dointvec_userhz_jiffies
,
1015 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
1016 .procname
= "nr_pdflush_threads",
1017 .data
= &nr_pdflush_threads
,
1018 .maxlen
= sizeof nr_pdflush_threads
,
1019 .mode
= 0444 /* read-only*/,
1020 .proc_handler
= &proc_dointvec
,
1023 .ctl_name
= VM_SWAPPINESS
,
1024 .procname
= "swappiness",
1025 .data
= &vm_swappiness
,
1026 .maxlen
= sizeof(vm_swappiness
),
1028 .proc_handler
= &proc_dointvec_minmax
,
1029 .strategy
= &sysctl_intvec
,
1031 .extra2
= &one_hundred
,
1033 #ifdef CONFIG_HUGETLB_PAGE
1035 .procname
= "nr_hugepages",
1037 .maxlen
= sizeof(unsigned long),
1039 .proc_handler
= &hugetlb_sysctl_handler
,
1040 .extra1
= (void *)&hugetlb_zero
,
1041 .extra2
= (void *)&hugetlb_infinity
,
1044 .ctl_name
= VM_HUGETLB_GROUP
,
1045 .procname
= "hugetlb_shm_group",
1046 .data
= &sysctl_hugetlb_shm_group
,
1047 .maxlen
= sizeof(gid_t
),
1049 .proc_handler
= &proc_dointvec
,
1052 .ctl_name
= CTL_UNNUMBERED
,
1053 .procname
= "hugepages_treat_as_movable",
1054 .data
= &hugepages_treat_as_movable
,
1055 .maxlen
= sizeof(int),
1057 .proc_handler
= &hugetlb_treat_movable_handler
,
1060 .ctl_name
= CTL_UNNUMBERED
,
1061 .procname
= "nr_overcommit_hugepages",
1063 .maxlen
= sizeof(unsigned long),
1065 .proc_handler
= &hugetlb_overcommit_handler
,
1066 .extra1
= (void *)&hugetlb_zero
,
1067 .extra2
= (void *)&hugetlb_infinity
,
1071 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
1072 .procname
= "lowmem_reserve_ratio",
1073 .data
= &sysctl_lowmem_reserve_ratio
,
1074 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
1076 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
1077 .strategy
= &sysctl_intvec
,
1080 .ctl_name
= VM_DROP_PAGECACHE
,
1081 .procname
= "drop_caches",
1082 .data
= &sysctl_drop_caches
,
1083 .maxlen
= sizeof(int),
1085 .proc_handler
= drop_caches_sysctl_handler
,
1086 .strategy
= &sysctl_intvec
,
1089 .ctl_name
= VM_MIN_FREE_KBYTES
,
1090 .procname
= "min_free_kbytes",
1091 .data
= &min_free_kbytes
,
1092 .maxlen
= sizeof(min_free_kbytes
),
1094 .proc_handler
= &min_free_kbytes_sysctl_handler
,
1095 .strategy
= &sysctl_intvec
,
1099 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
1100 .procname
= "percpu_pagelist_fraction",
1101 .data
= &percpu_pagelist_fraction
,
1102 .maxlen
= sizeof(percpu_pagelist_fraction
),
1104 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
1105 .strategy
= &sysctl_intvec
,
1106 .extra1
= &min_percpu_pagelist_fract
,
1110 .ctl_name
= VM_MAX_MAP_COUNT
,
1111 .procname
= "max_map_count",
1112 .data
= &sysctl_max_map_count
,
1113 .maxlen
= sizeof(sysctl_max_map_count
),
1115 .proc_handler
= &proc_dointvec
1119 .ctl_name
= CTL_UNNUMBERED
,
1120 .procname
= "nr_trim_pages",
1121 .data
= &sysctl_nr_trim_pages
,
1122 .maxlen
= sizeof(sysctl_nr_trim_pages
),
1124 .proc_handler
= &proc_dointvec_minmax
,
1125 .strategy
= &sysctl_intvec
,
1130 .ctl_name
= VM_LAPTOP_MODE
,
1131 .procname
= "laptop_mode",
1132 .data
= &laptop_mode
,
1133 .maxlen
= sizeof(laptop_mode
),
1135 .proc_handler
= &proc_dointvec_jiffies
,
1136 .strategy
= &sysctl_jiffies
,
1139 .ctl_name
= VM_BLOCK_DUMP
,
1140 .procname
= "block_dump",
1141 .data
= &block_dump
,
1142 .maxlen
= sizeof(block_dump
),
1144 .proc_handler
= &proc_dointvec
,
1145 .strategy
= &sysctl_intvec
,
1149 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
1150 .procname
= "vfs_cache_pressure",
1151 .data
= &sysctl_vfs_cache_pressure
,
1152 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
1154 .proc_handler
= &proc_dointvec
,
1155 .strategy
= &sysctl_intvec
,
1158 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1160 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
1161 .procname
= "legacy_va_layout",
1162 .data
= &sysctl_legacy_va_layout
,
1163 .maxlen
= sizeof(sysctl_legacy_va_layout
),
1165 .proc_handler
= &proc_dointvec
,
1166 .strategy
= &sysctl_intvec
,
1172 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
1173 .procname
= "zone_reclaim_mode",
1174 .data
= &zone_reclaim_mode
,
1175 .maxlen
= sizeof(zone_reclaim_mode
),
1177 .proc_handler
= &proc_dointvec
,
1178 .strategy
= &sysctl_intvec
,
1182 .ctl_name
= VM_MIN_UNMAPPED
,
1183 .procname
= "min_unmapped_ratio",
1184 .data
= &sysctl_min_unmapped_ratio
,
1185 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1187 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
1188 .strategy
= &sysctl_intvec
,
1190 .extra2
= &one_hundred
,
1193 .ctl_name
= VM_MIN_SLAB
,
1194 .procname
= "min_slab_ratio",
1195 .data
= &sysctl_min_slab_ratio
,
1196 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1198 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1199 .strategy
= &sysctl_intvec
,
1201 .extra2
= &one_hundred
,
1206 .ctl_name
= CTL_UNNUMBERED
,
1207 .procname
= "stat_interval",
1208 .data
= &sysctl_stat_interval
,
1209 .maxlen
= sizeof(sysctl_stat_interval
),
1211 .proc_handler
= &proc_dointvec_jiffies
,
1212 .strategy
= &sysctl_jiffies
,
1215 #ifdef CONFIG_SECURITY
1217 .ctl_name
= CTL_UNNUMBERED
,
1218 .procname
= "mmap_min_addr",
1219 .data
= &mmap_min_addr
,
1220 .maxlen
= sizeof(unsigned long),
1222 .proc_handler
= &proc_doulongvec_minmax
,
1227 .ctl_name
= CTL_UNNUMBERED
,
1228 .procname
= "numa_zonelist_order",
1229 .data
= &numa_zonelist_order
,
1230 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1232 .proc_handler
= &numa_zonelist_order_handler
,
1233 .strategy
= &sysctl_string
,
1236 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1237 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1239 .ctl_name
= VM_VDSO_ENABLED
,
1240 .procname
= "vdso_enabled",
1241 .data
= &vdso_enabled
,
1242 .maxlen
= sizeof(vdso_enabled
),
1244 .proc_handler
= &proc_dointvec
,
1245 .strategy
= &sysctl_intvec
,
1249 #ifdef CONFIG_HIGHMEM
1251 .ctl_name
= CTL_UNNUMBERED
,
1252 .procname
= "highmem_is_dirtyable",
1253 .data
= &vm_highmem_is_dirtyable
,
1254 .maxlen
= sizeof(vm_highmem_is_dirtyable
),
1256 .proc_handler
= &proc_dointvec_minmax
,
1257 .strategy
= &sysctl_intvec
,
1263 * NOTE: do not add new entries to this table unless you have read
1264 * Documentation/sysctl/ctl_unnumbered.txt
1269 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1270 static struct ctl_table binfmt_misc_table
[] = {
1275 static struct ctl_table fs_table
[] = {
1277 .ctl_name
= FS_NRINODE
,
1278 .procname
= "inode-nr",
1279 .data
= &inodes_stat
,
1280 .maxlen
= 2*sizeof(int),
1282 .proc_handler
= &proc_dointvec
,
1285 .ctl_name
= FS_STATINODE
,
1286 .procname
= "inode-state",
1287 .data
= &inodes_stat
,
1288 .maxlen
= 7*sizeof(int),
1290 .proc_handler
= &proc_dointvec
,
1293 .procname
= "file-nr",
1294 .data
= &files_stat
,
1295 .maxlen
= 3*sizeof(int),
1297 .proc_handler
= &proc_nr_files
,
1300 .ctl_name
= FS_MAXFILE
,
1301 .procname
= "file-max",
1302 .data
= &files_stat
.max_files
,
1303 .maxlen
= sizeof(int),
1305 .proc_handler
= &proc_dointvec
,
1308 .ctl_name
= CTL_UNNUMBERED
,
1309 .procname
= "nr_open",
1310 .data
= &sysctl_nr_open
,
1311 .maxlen
= sizeof(int),
1313 .proc_handler
= &proc_dointvec_minmax
,
1314 .extra1
= &sysctl_nr_open_min
,
1315 .extra2
= &sysctl_nr_open_max
,
1318 .ctl_name
= FS_DENTRY
,
1319 .procname
= "dentry-state",
1320 .data
= &dentry_stat
,
1321 .maxlen
= 6*sizeof(int),
1323 .proc_handler
= &proc_dointvec
,
1326 .ctl_name
= FS_OVERFLOWUID
,
1327 .procname
= "overflowuid",
1328 .data
= &fs_overflowuid
,
1329 .maxlen
= sizeof(int),
1331 .proc_handler
= &proc_dointvec_minmax
,
1332 .strategy
= &sysctl_intvec
,
1333 .extra1
= &minolduid
,
1334 .extra2
= &maxolduid
,
1337 .ctl_name
= FS_OVERFLOWGID
,
1338 .procname
= "overflowgid",
1339 .data
= &fs_overflowgid
,
1340 .maxlen
= sizeof(int),
1342 .proc_handler
= &proc_dointvec_minmax
,
1343 .strategy
= &sysctl_intvec
,
1344 .extra1
= &minolduid
,
1345 .extra2
= &maxolduid
,
1347 #ifdef CONFIG_FILE_LOCKING
1349 .ctl_name
= FS_LEASES
,
1350 .procname
= "leases-enable",
1351 .data
= &leases_enable
,
1352 .maxlen
= sizeof(int),
1354 .proc_handler
= &proc_dointvec
,
1357 #ifdef CONFIG_DNOTIFY
1359 .ctl_name
= FS_DIR_NOTIFY
,
1360 .procname
= "dir-notify-enable",
1361 .data
= &dir_notify_enable
,
1362 .maxlen
= sizeof(int),
1364 .proc_handler
= &proc_dointvec
,
1368 #ifdef CONFIG_FILE_LOCKING
1370 .ctl_name
= FS_LEASE_TIME
,
1371 .procname
= "lease-break-time",
1372 .data
= &lease_break_time
,
1373 .maxlen
= sizeof(int),
1375 .proc_handler
= &proc_dointvec_minmax
,
1376 .strategy
= &sysctl_intvec
,
1383 .procname
= "aio-nr",
1385 .maxlen
= sizeof(aio_nr
),
1387 .proc_handler
= &proc_doulongvec_minmax
,
1390 .procname
= "aio-max-nr",
1391 .data
= &aio_max_nr
,
1392 .maxlen
= sizeof(aio_max_nr
),
1394 .proc_handler
= &proc_doulongvec_minmax
,
1396 #endif /* CONFIG_AIO */
1397 #ifdef CONFIG_INOTIFY_USER
1399 .ctl_name
= FS_INOTIFY
,
1400 .procname
= "inotify",
1402 .child
= inotify_table
,
1407 .procname
= "epoll",
1409 .child
= epoll_table
,
1414 .ctl_name
= KERN_SETUID_DUMPABLE
,
1415 .procname
= "suid_dumpable",
1416 .data
= &suid_dumpable
,
1417 .maxlen
= sizeof(int),
1419 .proc_handler
= &proc_dointvec
,
1421 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1423 .ctl_name
= CTL_UNNUMBERED
,
1424 .procname
= "binfmt_misc",
1426 .child
= binfmt_misc_table
,
1430 * NOTE: do not add new entries to this table unless you have read
1431 * Documentation/sysctl/ctl_unnumbered.txt
1436 static struct ctl_table debug_table
[] = {
1437 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1439 .ctl_name
= CTL_UNNUMBERED
,
1440 .procname
= "exception-trace",
1441 .data
= &show_unhandled_signals
,
1442 .maxlen
= sizeof(int),
1444 .proc_handler
= proc_dointvec
1450 static struct ctl_table dev_table
[] = {
1454 static DEFINE_SPINLOCK(sysctl_lock
);
1456 /* called under sysctl_lock */
1457 static int use_table(struct ctl_table_header
*p
)
1459 if (unlikely(p
->unregistering
))
1465 /* called under sysctl_lock */
1466 static void unuse_table(struct ctl_table_header
*p
)
1469 if (unlikely(p
->unregistering
))
1470 complete(p
->unregistering
);
1473 /* called under sysctl_lock, will reacquire if has to wait */
1474 static void start_unregistering(struct ctl_table_header
*p
)
1477 * if p->used is 0, nobody will ever touch that entry again;
1478 * we'll eliminate all paths to it before dropping sysctl_lock
1480 if (unlikely(p
->used
)) {
1481 struct completion wait
;
1482 init_completion(&wait
);
1483 p
->unregistering
= &wait
;
1484 spin_unlock(&sysctl_lock
);
1485 wait_for_completion(&wait
);
1486 spin_lock(&sysctl_lock
);
1488 /* anything non-NULL; we'll never dereference it */
1489 p
->unregistering
= ERR_PTR(-EINVAL
);
1492 * do not remove from the list until nobody holds it; walking the
1493 * list in do_sysctl() relies on that.
1495 list_del_init(&p
->ctl_entry
);
1498 void sysctl_head_get(struct ctl_table_header
*head
)
1500 spin_lock(&sysctl_lock
);
1502 spin_unlock(&sysctl_lock
);
1505 void sysctl_head_put(struct ctl_table_header
*head
)
1507 spin_lock(&sysctl_lock
);
1510 spin_unlock(&sysctl_lock
);
1513 struct ctl_table_header
*sysctl_head_grab(struct ctl_table_header
*head
)
1517 spin_lock(&sysctl_lock
);
1518 if (!use_table(head
))
1519 head
= ERR_PTR(-ENOENT
);
1520 spin_unlock(&sysctl_lock
);
1524 void sysctl_head_finish(struct ctl_table_header
*head
)
1528 spin_lock(&sysctl_lock
);
1530 spin_unlock(&sysctl_lock
);
1533 static struct ctl_table_set
*
1534 lookup_header_set(struct ctl_table_root
*root
, struct nsproxy
*namespaces
)
1536 struct ctl_table_set
*set
= &root
->default_set
;
1538 set
= root
->lookup(root
, namespaces
);
1542 static struct list_head
*
1543 lookup_header_list(struct ctl_table_root
*root
, struct nsproxy
*namespaces
)
1545 struct ctl_table_set
*set
= lookup_header_set(root
, namespaces
);
1549 struct ctl_table_header
*__sysctl_head_next(struct nsproxy
*namespaces
,
1550 struct ctl_table_header
*prev
)
1552 struct ctl_table_root
*root
;
1553 struct list_head
*header_list
;
1554 struct ctl_table_header
*head
;
1555 struct list_head
*tmp
;
1557 spin_lock(&sysctl_lock
);
1560 tmp
= &prev
->ctl_entry
;
1564 tmp
= &root_table_header
.ctl_entry
;
1566 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1568 if (!use_table(head
))
1570 spin_unlock(&sysctl_lock
);
1575 header_list
= lookup_header_list(root
, namespaces
);
1576 if (tmp
!= header_list
)
1580 root
= list_entry(root
->root_list
.next
,
1581 struct ctl_table_root
, root_list
);
1582 if (root
== &sysctl_table_root
)
1584 header_list
= lookup_header_list(root
, namespaces
);
1585 } while (list_empty(header_list
));
1586 tmp
= header_list
->next
;
1589 spin_unlock(&sysctl_lock
);
1593 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1595 return __sysctl_head_next(current
->nsproxy
, prev
);
1598 void register_sysctl_root(struct ctl_table_root
*root
)
1600 spin_lock(&sysctl_lock
);
1601 list_add_tail(&root
->root_list
, &sysctl_table_root
.root_list
);
1602 spin_unlock(&sysctl_lock
);
1605 #ifdef CONFIG_SYSCTL_SYSCALL
1606 /* Perform the actual read/write of a sysctl table entry. */
1607 static int do_sysctl_strategy(struct ctl_table_root
*root
,
1608 struct ctl_table
*table
,
1609 void __user
*oldval
, size_t __user
*oldlenp
,
1610 void __user
*newval
, size_t newlen
)
1618 if (sysctl_perm(root
, table
, op
))
1621 if (table
->strategy
) {
1622 rc
= table
->strategy(table
, oldval
, oldlenp
, newval
, newlen
);
1629 /* If there is no strategy routine, or if the strategy returns
1630 * zero, proceed with automatic r/w */
1631 if (table
->data
&& table
->maxlen
) {
1632 rc
= sysctl_data(table
, oldval
, oldlenp
, newval
, newlen
);
1639 static int parse_table(int __user
*name
, int nlen
,
1640 void __user
*oldval
, size_t __user
*oldlenp
,
1641 void __user
*newval
, size_t newlen
,
1642 struct ctl_table_root
*root
,
1643 struct ctl_table
*table
)
1649 if (get_user(n
, name
))
1651 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1652 if (!table
->ctl_name
)
1654 if (n
== table
->ctl_name
) {
1657 if (sysctl_perm(root
, table
, MAY_EXEC
))
1661 table
= table
->child
;
1664 error
= do_sysctl_strategy(root
, table
,
1673 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1674 void __user
*newval
, size_t newlen
)
1676 struct ctl_table_header
*head
;
1677 int error
= -ENOTDIR
;
1679 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1683 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1687 for (head
= sysctl_head_next(NULL
); head
;
1688 head
= sysctl_head_next(head
)) {
1689 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1691 head
->root
, head
->ctl_table
);
1692 if (error
!= -ENOTDIR
) {
1693 sysctl_head_finish(head
);
1700 SYSCALL_DEFINE1(sysctl
, struct __sysctl_args __user
*, args
)
1702 struct __sysctl_args tmp
;
1705 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1708 error
= deprecated_sysctl_warning(&tmp
);
1713 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1714 tmp
.newval
, tmp
.newlen
);
1719 #endif /* CONFIG_SYSCTL_SYSCALL */
1722 * sysctl_perm does NOT grant the superuser all rights automatically, because
1723 * some sysctl variables are readonly even to root.
1726 static int test_perm(int mode
, int op
)
1728 if (!current_euid())
1730 else if (in_egroup_p(0))
1732 if ((op
& ~mode
& (MAY_READ
|MAY_WRITE
|MAY_EXEC
)) == 0)
1737 int sysctl_perm(struct ctl_table_root
*root
, struct ctl_table
*table
, int op
)
1742 error
= security_sysctl(table
, op
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
));
1746 if (root
->permissions
)
1747 mode
= root
->permissions(root
, current
->nsproxy
, table
);
1751 return test_perm(mode
, op
);
1754 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1756 for (; table
->ctl_name
|| table
->procname
; table
++) {
1757 table
->parent
= parent
;
1759 sysctl_set_parent(table
, table
->child
);
1763 static __init
int sysctl_init(void)
1765 sysctl_set_parent(NULL
, root_table
);
1766 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1769 err
= sysctl_check_table(current
->nsproxy
, root_table
);
1775 core_initcall(sysctl_init
);
1777 static struct ctl_table
*is_branch_in(struct ctl_table
*branch
,
1778 struct ctl_table
*table
)
1780 struct ctl_table
*p
;
1781 const char *s
= branch
->procname
;
1783 /* branch should have named subdirectory as its first element */
1784 if (!s
|| !branch
->child
)
1787 /* ... and nothing else */
1788 if (branch
[1].procname
|| branch
[1].ctl_name
)
1791 /* table should contain subdirectory with the same name */
1792 for (p
= table
; p
->procname
|| p
->ctl_name
; p
++) {
1795 if (p
->procname
&& strcmp(p
->procname
, s
) == 0)
1801 /* see if attaching q to p would be an improvement */
1802 static void try_attach(struct ctl_table_header
*p
, struct ctl_table_header
*q
)
1804 struct ctl_table
*to
= p
->ctl_table
, *by
= q
->ctl_table
;
1805 struct ctl_table
*next
;
1807 int not_in_parent
= !p
->attached_by
;
1809 while ((next
= is_branch_in(by
, to
)) != NULL
) {
1810 if (by
== q
->attached_by
)
1812 if (to
== p
->attached_by
)
1818 if (is_better
&& not_in_parent
) {
1819 q
->attached_by
= by
;
1820 q
->attached_to
= to
;
1826 * __register_sysctl_paths - register a sysctl hierarchy
1827 * @root: List of sysctl headers to register on
1828 * @namespaces: Data to compute which lists of sysctl entries are visible
1829 * @path: The path to the directory the sysctl table is in.
1830 * @table: the top-level table structure
1832 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1833 * array. A completely 0 filled entry terminates the table.
1835 * The members of the &struct ctl_table structure are used as follows:
1837 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1838 * must be unique within that level of sysctl
1840 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1841 * enter a sysctl file
1843 * data - a pointer to data for use by proc_handler
1845 * maxlen - the maximum size in bytes of the data
1847 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1849 * child - a pointer to the child sysctl table if this entry is a directory, or
1852 * proc_handler - the text handler routine (described below)
1854 * strategy - the strategy routine (described below)
1856 * de - for internal use by the sysctl routines
1858 * extra1, extra2 - extra pointers usable by the proc handler routines
1860 * Leaf nodes in the sysctl tree will be represented by a single file
1861 * under /proc; non-leaf nodes will be represented by directories.
1863 * sysctl(2) can automatically manage read and write requests through
1864 * the sysctl table. The data and maxlen fields of the ctl_table
1865 * struct enable minimal validation of the values being written to be
1866 * performed, and the mode field allows minimal authentication.
1868 * More sophisticated management can be enabled by the provision of a
1869 * strategy routine with the table entry. This will be called before
1870 * any automatic read or write of the data is performed.
1872 * The strategy routine may return
1874 * < 0 - Error occurred (error is passed to user process)
1876 * 0 - OK - proceed with automatic read or write.
1878 * > 0 - OK - read or write has been done by the strategy routine, so
1879 * return immediately.
1881 * There must be a proc_handler routine for any terminal nodes
1882 * mirrored under /proc/sys (non-terminals are handled by a built-in
1883 * directory handler). Several default handlers are available to
1884 * cover common cases -
1886 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1887 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1888 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1890 * It is the handler's job to read the input buffer from user memory
1891 * and process it. The handler should return 0 on success.
1893 * This routine returns %NULL on a failure to register, and a pointer
1894 * to the table header on success.
1896 struct ctl_table_header
*__register_sysctl_paths(
1897 struct ctl_table_root
*root
,
1898 struct nsproxy
*namespaces
,
1899 const struct ctl_path
*path
, struct ctl_table
*table
)
1901 struct ctl_table_header
*header
;
1902 struct ctl_table
*new, **prevp
;
1903 unsigned int n
, npath
;
1904 struct ctl_table_set
*set
;
1906 /* Count the path components */
1907 for (npath
= 0; path
[npath
].ctl_name
|| path
[npath
].procname
; ++npath
)
1911 * For each path component, allocate a 2-element ctl_table array.
1912 * The first array element will be filled with the sysctl entry
1913 * for this, the second will be the sentinel (ctl_name == 0).
1915 * We allocate everything in one go so that we don't have to
1916 * worry about freeing additional memory in unregister_sysctl_table.
1918 header
= kzalloc(sizeof(struct ctl_table_header
) +
1919 (2 * npath
* sizeof(struct ctl_table
)), GFP_KERNEL
);
1923 new = (struct ctl_table
*) (header
+ 1);
1925 /* Now connect the dots */
1926 prevp
= &header
->ctl_table
;
1927 for (n
= 0; n
< npath
; ++n
, ++path
) {
1928 /* Copy the procname */
1929 new->procname
= path
->procname
;
1930 new->ctl_name
= path
->ctl_name
;
1934 prevp
= &new->child
;
1939 header
->ctl_table_arg
= table
;
1941 INIT_LIST_HEAD(&header
->ctl_entry
);
1943 header
->unregistering
= NULL
;
1944 header
->root
= root
;
1945 sysctl_set_parent(NULL
, header
->ctl_table
);
1947 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1948 if (sysctl_check_table(namespaces
, header
->ctl_table
)) {
1953 spin_lock(&sysctl_lock
);
1954 header
->set
= lookup_header_set(root
, namespaces
);
1955 header
->attached_by
= header
->ctl_table
;
1956 header
->attached_to
= root_table
;
1957 header
->parent
= &root_table_header
;
1958 for (set
= header
->set
; set
; set
= set
->parent
) {
1959 struct ctl_table_header
*p
;
1960 list_for_each_entry(p
, &set
->list
, ctl_entry
) {
1961 if (p
->unregistering
)
1963 try_attach(p
, header
);
1966 header
->parent
->count
++;
1967 list_add_tail(&header
->ctl_entry
, &header
->set
->list
);
1968 spin_unlock(&sysctl_lock
);
1974 * register_sysctl_table_path - register a sysctl table hierarchy
1975 * @path: The path to the directory the sysctl table is in.
1976 * @table: the top-level table structure
1978 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1979 * array. A completely 0 filled entry terminates the table.
1981 * See __register_sysctl_paths for more details.
1983 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
1984 struct ctl_table
*table
)
1986 return __register_sysctl_paths(&sysctl_table_root
, current
->nsproxy
,
1991 * register_sysctl_table - register a sysctl table hierarchy
1992 * @table: the top-level table structure
1994 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1995 * array. A completely 0 filled entry terminates the table.
1997 * See register_sysctl_paths for more details.
1999 struct ctl_table_header
*register_sysctl_table(struct ctl_table
*table
)
2001 static const struct ctl_path null_path
[] = { {} };
2003 return register_sysctl_paths(null_path
, table
);
2007 * unregister_sysctl_table - unregister a sysctl table hierarchy
2008 * @header: the header returned from register_sysctl_table
2010 * Unregisters the sysctl table and all children. proc entries may not
2011 * actually be removed until they are no longer used by anyone.
2013 void unregister_sysctl_table(struct ctl_table_header
* header
)
2020 spin_lock(&sysctl_lock
);
2021 start_unregistering(header
);
2022 if (!--header
->parent
->count
) {
2024 kfree(header
->parent
);
2026 if (!--header
->count
)
2028 spin_unlock(&sysctl_lock
);
2031 int sysctl_is_seen(struct ctl_table_header
*p
)
2033 struct ctl_table_set
*set
= p
->set
;
2035 spin_lock(&sysctl_lock
);
2036 if (p
->unregistering
)
2038 else if (!set
->is_seen
)
2041 res
= set
->is_seen(set
);
2042 spin_unlock(&sysctl_lock
);
2046 void setup_sysctl_set(struct ctl_table_set
*p
,
2047 struct ctl_table_set
*parent
,
2048 int (*is_seen
)(struct ctl_table_set
*))
2050 INIT_LIST_HEAD(&p
->list
);
2051 p
->parent
= parent
? parent
: &sysctl_table_root
.default_set
;
2052 p
->is_seen
= is_seen
;
2055 #else /* !CONFIG_SYSCTL */
2056 struct ctl_table_header
*register_sysctl_table(struct ctl_table
* table
)
2061 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
2062 struct ctl_table
*table
)
2067 void unregister_sysctl_table(struct ctl_table_header
* table
)
2071 void setup_sysctl_set(struct ctl_table_set
*p
,
2072 struct ctl_table_set
*parent
,
2073 int (*is_seen
)(struct ctl_table_set
*))
2077 void sysctl_head_put(struct ctl_table_header
*head
)
2081 #endif /* CONFIG_SYSCTL */
2087 #ifdef CONFIG_PROC_SYSCTL
2089 static int _proc_do_string(void* data
, int maxlen
, int write
,
2090 struct file
*filp
, void __user
*buffer
,
2091 size_t *lenp
, loff_t
*ppos
)
2097 if (!data
|| !maxlen
|| !*lenp
) {
2105 while (len
< *lenp
) {
2106 if (get_user(c
, p
++))
2108 if (c
== 0 || c
== '\n')
2114 if(copy_from_user(data
, buffer
, len
))
2116 ((char *) data
)[len
] = 0;
2134 if(copy_to_user(buffer
, data
, len
))
2137 if(put_user('\n', ((char __user
*) buffer
) + len
))
2148 * proc_dostring - read a string sysctl
2149 * @table: the sysctl table
2150 * @write: %TRUE if this is a write to the sysctl file
2151 * @filp: the file structure
2152 * @buffer: the user buffer
2153 * @lenp: the size of the user buffer
2154 * @ppos: file position
2156 * Reads/writes a string from/to the user buffer. If the kernel
2157 * buffer provided is not large enough to hold the string, the
2158 * string is truncated. The copied string is %NULL-terminated.
2159 * If the string is being read by the user process, it is copied
2160 * and a newline '\n' is added. It is truncated if the buffer is
2163 * Returns 0 on success.
2165 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2166 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2168 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
2169 buffer
, lenp
, ppos
);
2173 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
2175 int write
, void *data
)
2178 *valp
= *negp
? -*lvalp
: *lvalp
;
2183 *lvalp
= (unsigned long)-val
;
2186 *lvalp
= (unsigned long)val
;
2192 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
2193 int write
, struct file
*filp
, void __user
*buffer
,
2194 size_t *lenp
, loff_t
*ppos
,
2195 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
2196 int write
, void *data
),
2199 #define TMPBUFLEN 21
2200 int *i
, vleft
, first
=1, neg
, val
;
2204 char buf
[TMPBUFLEN
], *p
;
2205 char __user
*s
= buffer
;
2207 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
2208 (*ppos
&& !write
)) {
2213 i
= (int *) tbl_data
;
2214 vleft
= table
->maxlen
/ sizeof(*i
);
2218 conv
= do_proc_dointvec_conv
;
2220 for (; left
&& vleft
--; i
++, first
=0) {
2235 if (len
> sizeof(buf
) - 1)
2236 len
= sizeof(buf
) - 1;
2237 if (copy_from_user(buf
, s
, len
))
2241 if (*p
== '-' && left
> 1) {
2245 if (*p
< '0' || *p
> '9')
2248 lval
= simple_strtoul(p
, &p
, 0);
2251 if ((len
< left
) && *p
&& !isspace(*p
))
2258 if (conv(&neg
, &lval
, i
, 1, data
))
2265 if (conv(&neg
, &lval
, i
, 0, data
))
2268 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
2272 if(copy_to_user(s
, buf
, len
))
2279 if (!write
&& !first
&& left
) {
2280 if(put_user('\n', s
))
2287 if (get_user(c
, s
++))
2302 static int do_proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2303 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
2304 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
2305 int write
, void *data
),
2308 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
2309 buffer
, lenp
, ppos
, conv
, data
);
2313 * proc_dointvec - read a vector of integers
2314 * @table: the sysctl table
2315 * @write: %TRUE if this is a write to the sysctl file
2316 * @filp: the file structure
2317 * @buffer: the user buffer
2318 * @lenp: the size of the user buffer
2319 * @ppos: file position
2321 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2322 * values from/to the user buffer, treated as an ASCII string.
2324 * Returns 0 on success.
2326 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2327 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2329 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2334 * Taint values can only be increased
2335 * This means we can safely use a temporary.
2337 static int proc_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
2338 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2341 unsigned long tmptaint
= get_taint();
2344 if (write
&& !capable(CAP_SYS_ADMIN
))
2349 err
= proc_doulongvec_minmax(&t
, write
, filp
, buffer
, lenp
, ppos
);
2355 * Poor man's atomic or. Not worth adding a primitive
2356 * to everyone's atomic.h for this
2359 for (i
= 0; i
< BITS_PER_LONG
&& tmptaint
>> i
; i
++) {
2360 if ((tmptaint
>> i
) & 1)
2368 struct do_proc_dointvec_minmax_conv_param
{
2373 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
2375 int write
, void *data
)
2377 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
2379 int val
= *negp
? -*lvalp
: *lvalp
;
2380 if ((param
->min
&& *param
->min
> val
) ||
2381 (param
->max
&& *param
->max
< val
))
2388 *lvalp
= (unsigned long)-val
;
2391 *lvalp
= (unsigned long)val
;
2398 * proc_dointvec_minmax - read a vector of integers with min/max values
2399 * @table: the sysctl table
2400 * @write: %TRUE if this is a write to the sysctl file
2401 * @filp: the file structure
2402 * @buffer: the user buffer
2403 * @lenp: the size of the user buffer
2404 * @ppos: file position
2406 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2407 * values from/to the user buffer, treated as an ASCII string.
2409 * This routine will ensure the values are within the range specified by
2410 * table->extra1 (min) and table->extra2 (max).
2412 * Returns 0 on success.
2414 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2415 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2417 struct do_proc_dointvec_minmax_conv_param param
= {
2418 .min
= (int *) table
->extra1
,
2419 .max
= (int *) table
->extra2
,
2421 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2422 do_proc_dointvec_minmax_conv
, ¶m
);
2425 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
2427 void __user
*buffer
,
2428 size_t *lenp
, loff_t
*ppos
,
2429 unsigned long convmul
,
2430 unsigned long convdiv
)
2432 #define TMPBUFLEN 21
2433 unsigned long *i
, *min
, *max
, val
;
2434 int vleft
, first
=1, neg
;
2436 char buf
[TMPBUFLEN
], *p
;
2437 char __user
*s
= buffer
;
2439 if (!data
|| !table
->maxlen
|| !*lenp
||
2440 (*ppos
&& !write
)) {
2445 i
= (unsigned long *) data
;
2446 min
= (unsigned long *) table
->extra1
;
2447 max
= (unsigned long *) table
->extra2
;
2448 vleft
= table
->maxlen
/ sizeof(unsigned long);
2451 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
2466 if (len
> TMPBUFLEN
-1)
2468 if (copy_from_user(buf
, s
, len
))
2472 if (*p
== '-' && left
> 1) {
2476 if (*p
< '0' || *p
> '9')
2478 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2480 if ((len
< left
) && *p
&& !isspace(*p
))
2489 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2496 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2500 if(copy_to_user(s
, buf
, len
))
2507 if (!write
&& !first
&& left
) {
2508 if(put_user('\n', s
))
2515 if (get_user(c
, s
++))
2530 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2532 void __user
*buffer
,
2533 size_t *lenp
, loff_t
*ppos
,
2534 unsigned long convmul
,
2535 unsigned long convdiv
)
2537 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2538 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2542 * proc_doulongvec_minmax - read a vector of long integers 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.
2553 * This routine will ensure the values are within the range specified by
2554 * table->extra1 (min) and table->extra2 (max).
2556 * Returns 0 on success.
2558 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2559 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2561 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2565 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2566 * @table: the sysctl table
2567 * @write: %TRUE if this is a write to the sysctl file
2568 * @filp: the file structure
2569 * @buffer: the user buffer
2570 * @lenp: the size of the user buffer
2571 * @ppos: file position
2573 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2574 * values from/to the user buffer, treated as an ASCII string. The values
2575 * are treated as milliseconds, and converted to jiffies when they are stored.
2577 * This routine will ensure the values are within the range specified by
2578 * table->extra1 (min) and table->extra2 (max).
2580 * Returns 0 on success.
2582 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2584 void __user
*buffer
,
2585 size_t *lenp
, loff_t
*ppos
)
2587 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2588 lenp
, ppos
, HZ
, 1000l);
2592 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2594 int write
, void *data
)
2597 if (*lvalp
> LONG_MAX
/ HZ
)
2599 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2605 lval
= (unsigned long)-val
;
2608 lval
= (unsigned long)val
;
2615 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2617 int write
, void *data
)
2620 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2622 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2628 lval
= (unsigned long)-val
;
2631 lval
= (unsigned long)val
;
2633 *lvalp
= jiffies_to_clock_t(lval
);
2638 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2640 int write
, void *data
)
2643 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2649 lval
= (unsigned long)-val
;
2652 lval
= (unsigned long)val
;
2654 *lvalp
= jiffies_to_msecs(lval
);
2660 * proc_dointvec_jiffies - read a vector of integers as 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: 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 seconds, and are converted into
2673 * Returns 0 on success.
2675 int proc_dointvec_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_jiffies_conv
,NULL
);
2683 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
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: pointer to the file position
2691 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2692 * values from/to the user buffer, treated as an ASCII string.
2693 * The values read are assumed to be in 1/USER_HZ seconds, and
2694 * are converted into jiffies.
2696 * Returns 0 on success.
2698 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2699 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2701 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2702 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2706 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2707 * @table: the sysctl table
2708 * @write: %TRUE if this is a write to the sysctl file
2709 * @filp: the file structure
2710 * @buffer: the user buffer
2711 * @lenp: the size of the user buffer
2712 * @ppos: file position
2713 * @ppos: the current position in the file
2715 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2716 * values from/to the user buffer, treated as an ASCII string.
2717 * The values read are assumed to be in 1/1000 seconds, and
2718 * are converted into jiffies.
2720 * Returns 0 on success.
2722 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2723 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2725 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2726 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2729 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
2730 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2732 struct pid
*new_pid
;
2736 tmp
= pid_vnr(cad_pid
);
2738 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2739 lenp
, ppos
, NULL
, NULL
);
2743 new_pid
= find_get_pid(tmp
);
2747 put_pid(xchg(&cad_pid
, new_pid
));
2751 #else /* CONFIG_PROC_FS */
2753 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2754 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2759 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2760 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2765 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2766 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2771 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2772 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2777 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2778 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2783 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2784 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2789 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2790 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2795 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2797 void __user
*buffer
,
2798 size_t *lenp
, loff_t
*ppos
)
2804 #endif /* CONFIG_PROC_FS */
2807 #ifdef CONFIG_SYSCTL_SYSCALL
2809 * General sysctl support routines
2812 /* The generic sysctl data routine (used if no strategy routine supplied) */
2813 int sysctl_data(struct ctl_table
*table
,
2814 void __user
*oldval
, size_t __user
*oldlenp
,
2815 void __user
*newval
, size_t newlen
)
2819 /* Get out of I don't have a variable */
2820 if (!table
->data
|| !table
->maxlen
)
2823 if (oldval
&& oldlenp
) {
2824 if (get_user(len
, oldlenp
))
2827 if (len
> table
->maxlen
)
2828 len
= table
->maxlen
;
2829 if (copy_to_user(oldval
, table
->data
, len
))
2831 if (put_user(len
, oldlenp
))
2836 if (newval
&& newlen
) {
2837 if (newlen
> table
->maxlen
)
2838 newlen
= table
->maxlen
;
2840 if (copy_from_user(table
->data
, newval
, newlen
))
2846 /* The generic string strategy routine: */
2847 int sysctl_string(struct ctl_table
*table
,
2848 void __user
*oldval
, size_t __user
*oldlenp
,
2849 void __user
*newval
, size_t newlen
)
2851 if (!table
->data
|| !table
->maxlen
)
2854 if (oldval
&& oldlenp
) {
2856 if (get_user(bufsize
, oldlenp
))
2859 size_t len
= strlen(table
->data
), copied
;
2861 /* This shouldn't trigger for a well-formed sysctl */
2862 if (len
> table
->maxlen
)
2863 len
= table
->maxlen
;
2865 /* Copy up to a max of bufsize-1 bytes of the string */
2866 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2868 if (copy_to_user(oldval
, table
->data
, copied
) ||
2869 put_user(0, (char __user
*)(oldval
+ copied
)))
2871 if (put_user(len
, oldlenp
))
2875 if (newval
&& newlen
) {
2876 size_t len
= newlen
;
2877 if (len
> table
->maxlen
)
2878 len
= table
->maxlen
;
2879 if(copy_from_user(table
->data
, newval
, len
))
2881 if (len
== table
->maxlen
)
2883 ((char *) table
->data
)[len
] = 0;
2889 * This function makes sure that all of the integers in the vector
2890 * are between the minimum and maximum values given in the arrays
2891 * table->extra1 and table->extra2, respectively.
2893 int sysctl_intvec(struct ctl_table
*table
,
2894 void __user
*oldval
, size_t __user
*oldlenp
,
2895 void __user
*newval
, size_t newlen
)
2898 if (newval
&& newlen
) {
2899 int __user
*vec
= (int __user
*) newval
;
2900 int *min
= (int *) table
->extra1
;
2901 int *max
= (int *) table
->extra2
;
2905 if (newlen
% sizeof(int) != 0)
2908 if (!table
->extra1
&& !table
->extra2
)
2911 if (newlen
> table
->maxlen
)
2912 newlen
= table
->maxlen
;
2913 length
= newlen
/ sizeof(int);
2915 for (i
= 0; i
< length
; i
++) {
2917 if (get_user(value
, vec
+ i
))
2919 if (min
&& value
< min
[i
])
2921 if (max
&& value
> max
[i
])
2928 /* Strategy function to convert jiffies to seconds */
2929 int sysctl_jiffies(struct ctl_table
*table
,
2930 void __user
*oldval
, size_t __user
*oldlenp
,
2931 void __user
*newval
, size_t newlen
)
2933 if (oldval
&& oldlenp
) {
2936 if (get_user(olen
, oldlenp
))
2941 if (olen
< sizeof(int))
2944 val
= *(int *)(table
->data
) / HZ
;
2945 if (put_user(val
, (int __user
*)oldval
))
2947 if (put_user(sizeof(int), oldlenp
))
2951 if (newval
&& newlen
) {
2953 if (newlen
!= sizeof(int))
2955 if (get_user(new, (int __user
*)newval
))
2957 *(int *)(table
->data
) = new*HZ
;
2962 /* Strategy function to convert jiffies to seconds */
2963 int sysctl_ms_jiffies(struct ctl_table
*table
,
2964 void __user
*oldval
, size_t __user
*oldlenp
,
2965 void __user
*newval
, size_t newlen
)
2967 if (oldval
&& oldlenp
) {
2970 if (get_user(olen
, oldlenp
))
2975 if (olen
< sizeof(int))
2978 val
= jiffies_to_msecs(*(int *)(table
->data
));
2979 if (put_user(val
, (int __user
*)oldval
))
2981 if (put_user(sizeof(int), oldlenp
))
2985 if (newval
&& newlen
) {
2987 if (newlen
!= sizeof(int))
2989 if (get_user(new, (int __user
*)newval
))
2991 *(int *)(table
->data
) = msecs_to_jiffies(new);
2998 #else /* CONFIG_SYSCTL_SYSCALL */
3001 SYSCALL_DEFINE1(sysctl
, struct __sysctl_args __user
*, args
)
3003 struct __sysctl_args tmp
;
3006 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
3009 error
= deprecated_sysctl_warning(&tmp
);
3011 /* If no error reading the parameters then just -ENOSYS ... */
3018 int sysctl_data(struct ctl_table
*table
,
3019 void __user
*oldval
, size_t __user
*oldlenp
,
3020 void __user
*newval
, size_t newlen
)
3025 int sysctl_string(struct ctl_table
*table
,
3026 void __user
*oldval
, size_t __user
*oldlenp
,
3027 void __user
*newval
, size_t newlen
)
3032 int sysctl_intvec(struct ctl_table
*table
,
3033 void __user
*oldval
, size_t __user
*oldlenp
,
3034 void __user
*newval
, size_t newlen
)
3039 int sysctl_jiffies(struct ctl_table
*table
,
3040 void __user
*oldval
, size_t __user
*oldlenp
,
3041 void __user
*newval
, size_t newlen
)
3046 int sysctl_ms_jiffies(struct ctl_table
*table
,
3047 void __user
*oldval
, size_t __user
*oldlenp
,
3048 void __user
*newval
, size_t newlen
)
3053 #endif /* CONFIG_SYSCTL_SYSCALL */
3055 static int deprecated_sysctl_warning(struct __sysctl_args
*args
)
3057 static int msg_count
;
3058 int name
[CTL_MAXNAME
];
3061 /* Check args->nlen. */
3062 if (args
->nlen
< 0 || args
->nlen
> CTL_MAXNAME
)
3065 /* Read in the sysctl name for better debug message logging */
3066 for (i
= 0; i
< args
->nlen
; i
++)
3067 if (get_user(name
[i
], args
->name
+ i
))
3070 /* Ignore accesses to kernel.version */
3071 if ((args
->nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
3074 if (msg_count
< 5) {
3077 "warning: process `%s' used the deprecated sysctl "
3078 "system call with ", current
->comm
);
3079 for (i
= 0; i
< args
->nlen
; i
++)
3080 printk("%d.", name
[i
]);
3087 * No sense putting this after each symbol definition, twice,
3088 * exception granted :-)
3090 EXPORT_SYMBOL(proc_dointvec
);
3091 EXPORT_SYMBOL(proc_dointvec_jiffies
);
3092 EXPORT_SYMBOL(proc_dointvec_minmax
);
3093 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
3094 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
3095 EXPORT_SYMBOL(proc_dostring
);
3096 EXPORT_SYMBOL(proc_doulongvec_minmax
);
3097 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
3098 EXPORT_SYMBOL(register_sysctl_table
);
3099 EXPORT_SYMBOL(register_sysctl_paths
);
3100 EXPORT_SYMBOL(sysctl_intvec
);
3101 EXPORT_SYMBOL(sysctl_jiffies
);
3102 EXPORT_SYMBOL(sysctl_ms_jiffies
);
3103 EXPORT_SYMBOL(sysctl_string
);
3104 EXPORT_SYMBOL(sysctl_data
);
3105 EXPORT_SYMBOL(unregister_sysctl_table
);