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 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_DETECT_SOFTLOCKUP)
94 #ifdef CONFIG_DETECT_SOFTLOCKUP
95 static int sixty
= 60;
96 static int neg_one
= -1;
99 #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
;
149 #ifdef CONFIG_RT_MUTEXES
150 extern int max_lock_depth
;
153 #ifdef CONFIG_PROC_SYSCTL
154 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
155 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
156 static int proc_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
157 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
160 static struct ctl_table root_table
[];
161 static struct ctl_table_root sysctl_table_root
;
162 static struct ctl_table_header root_table_header
= {
164 .ctl_table
= root_table
,
165 .ctl_entry
= LIST_HEAD_INIT(sysctl_table_root
.default_set
.list
),
166 .root
= &sysctl_table_root
,
167 .set
= &sysctl_table_root
.default_set
,
169 static struct ctl_table_root sysctl_table_root
= {
170 .root_list
= LIST_HEAD_INIT(sysctl_table_root
.root_list
),
171 .default_set
.list
= LIST_HEAD_INIT(root_table_header
.ctl_entry
),
174 static struct ctl_table kern_table
[];
175 static struct ctl_table vm_table
[];
176 static struct ctl_table fs_table
[];
177 static struct ctl_table debug_table
[];
178 static struct ctl_table dev_table
[];
179 extern struct ctl_table random_table
[];
180 #ifdef CONFIG_INOTIFY_USER
181 extern struct ctl_table inotify_table
[];
184 extern struct ctl_table epoll_table
[];
187 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
188 int sysctl_legacy_va_layout
;
191 extern int prove_locking
;
192 extern int lock_stat
;
194 /* The default sysctl tables: */
196 static struct ctl_table root_table
[] = {
198 .ctl_name
= CTL_KERN
,
199 .procname
= "kernel",
216 .ctl_name
= CTL_DEBUG
,
219 .child
= debug_table
,
228 * NOTE: do not add new entries to this table unless you have read
229 * Documentation/sysctl/ctl_unnumbered.txt
234 #ifdef CONFIG_SCHED_DEBUG
235 static int min_sched_granularity_ns
= 100000; /* 100 usecs */
236 static int max_sched_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
237 static int min_wakeup_granularity_ns
; /* 0 usecs */
238 static int max_wakeup_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
241 static struct ctl_table kern_table
[] = {
242 #ifdef CONFIG_SCHED_DEBUG
244 .ctl_name
= CTL_UNNUMBERED
,
245 .procname
= "sched_min_granularity_ns",
246 .data
= &sysctl_sched_min_granularity
,
247 .maxlen
= sizeof(unsigned int),
249 .proc_handler
= &sched_nr_latency_handler
,
250 .strategy
= &sysctl_intvec
,
251 .extra1
= &min_sched_granularity_ns
,
252 .extra2
= &max_sched_granularity_ns
,
255 .ctl_name
= CTL_UNNUMBERED
,
256 .procname
= "sched_latency_ns",
257 .data
= &sysctl_sched_latency
,
258 .maxlen
= sizeof(unsigned int),
260 .proc_handler
= &sched_nr_latency_handler
,
261 .strategy
= &sysctl_intvec
,
262 .extra1
= &min_sched_granularity_ns
,
263 .extra2
= &max_sched_granularity_ns
,
266 .ctl_name
= CTL_UNNUMBERED
,
267 .procname
= "sched_wakeup_granularity_ns",
268 .data
= &sysctl_sched_wakeup_granularity
,
269 .maxlen
= sizeof(unsigned int),
271 .proc_handler
= &proc_dointvec_minmax
,
272 .strategy
= &sysctl_intvec
,
273 .extra1
= &min_wakeup_granularity_ns
,
274 .extra2
= &max_wakeup_granularity_ns
,
277 .ctl_name
= CTL_UNNUMBERED
,
278 .procname
= "sched_shares_ratelimit",
279 .data
= &sysctl_sched_shares_ratelimit
,
280 .maxlen
= sizeof(unsigned int),
282 .proc_handler
= &proc_dointvec
,
285 .ctl_name
= CTL_UNNUMBERED
,
286 .procname
= "sched_shares_thresh",
287 .data
= &sysctl_sched_shares_thresh
,
288 .maxlen
= sizeof(unsigned int),
290 .proc_handler
= &proc_dointvec_minmax
,
291 .strategy
= &sysctl_intvec
,
295 .ctl_name
= CTL_UNNUMBERED
,
296 .procname
= "sched_child_runs_first",
297 .data
= &sysctl_sched_child_runs_first
,
298 .maxlen
= sizeof(unsigned int),
300 .proc_handler
= &proc_dointvec
,
303 .ctl_name
= CTL_UNNUMBERED
,
304 .procname
= "sched_features",
305 .data
= &sysctl_sched_features
,
306 .maxlen
= sizeof(unsigned int),
308 .proc_handler
= &proc_dointvec
,
311 .ctl_name
= CTL_UNNUMBERED
,
312 .procname
= "sched_migration_cost",
313 .data
= &sysctl_sched_migration_cost
,
314 .maxlen
= sizeof(unsigned int),
316 .proc_handler
= &proc_dointvec
,
319 .ctl_name
= CTL_UNNUMBERED
,
320 .procname
= "sched_nr_migrate",
321 .data
= &sysctl_sched_nr_migrate
,
322 .maxlen
= sizeof(unsigned int),
324 .proc_handler
= &proc_dointvec
,
328 .ctl_name
= CTL_UNNUMBERED
,
329 .procname
= "sched_rt_period_us",
330 .data
= &sysctl_sched_rt_period
,
331 .maxlen
= sizeof(unsigned int),
333 .proc_handler
= &sched_rt_handler
,
336 .ctl_name
= CTL_UNNUMBERED
,
337 .procname
= "sched_rt_runtime_us",
338 .data
= &sysctl_sched_rt_runtime
,
339 .maxlen
= sizeof(int),
341 .proc_handler
= &sched_rt_handler
,
344 .ctl_name
= CTL_UNNUMBERED
,
345 .procname
= "sched_compat_yield",
346 .data
= &sysctl_sched_compat_yield
,
347 .maxlen
= sizeof(unsigned int),
349 .proc_handler
= &proc_dointvec
,
351 #ifdef CONFIG_PROVE_LOCKING
353 .ctl_name
= CTL_UNNUMBERED
,
354 .procname
= "prove_locking",
355 .data
= &prove_locking
,
356 .maxlen
= sizeof(int),
358 .proc_handler
= &proc_dointvec
,
361 #ifdef CONFIG_LOCK_STAT
363 .ctl_name
= CTL_UNNUMBERED
,
364 .procname
= "lock_stat",
366 .maxlen
= sizeof(int),
368 .proc_handler
= &proc_dointvec
,
372 .ctl_name
= KERN_PANIC
,
374 .data
= &panic_timeout
,
375 .maxlen
= sizeof(int),
377 .proc_handler
= &proc_dointvec
,
380 .ctl_name
= KERN_CORE_USES_PID
,
381 .procname
= "core_uses_pid",
382 .data
= &core_uses_pid
,
383 .maxlen
= sizeof(int),
385 .proc_handler
= &proc_dointvec
,
388 .ctl_name
= KERN_CORE_PATTERN
,
389 .procname
= "core_pattern",
390 .data
= core_pattern
,
391 .maxlen
= CORENAME_MAX_SIZE
,
393 .proc_handler
= &proc_dostring
,
394 .strategy
= &sysctl_string
,
396 #ifdef CONFIG_PROC_SYSCTL
398 .procname
= "tainted",
399 .maxlen
= sizeof(long),
401 .proc_handler
= &proc_taint
,
404 #ifdef CONFIG_LATENCYTOP
406 .procname
= "latencytop",
407 .data
= &latencytop_enabled
,
408 .maxlen
= sizeof(int),
410 .proc_handler
= &proc_dointvec
,
413 #ifdef CONFIG_BLK_DEV_INITRD
415 .ctl_name
= KERN_REALROOTDEV
,
416 .procname
= "real-root-dev",
417 .data
= &real_root_dev
,
418 .maxlen
= sizeof(int),
420 .proc_handler
= &proc_dointvec
,
424 .ctl_name
= CTL_UNNUMBERED
,
425 .procname
= "print-fatal-signals",
426 .data
= &print_fatal_signals
,
427 .maxlen
= sizeof(int),
429 .proc_handler
= &proc_dointvec
,
433 .ctl_name
= KERN_SPARC_REBOOT
,
434 .procname
= "reboot-cmd",
435 .data
= reboot_command
,
438 .proc_handler
= &proc_dostring
,
439 .strategy
= &sysctl_string
,
442 .ctl_name
= KERN_SPARC_STOP_A
,
443 .procname
= "stop-a",
444 .data
= &stop_a_enabled
,
445 .maxlen
= sizeof (int),
447 .proc_handler
= &proc_dointvec
,
450 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
451 .procname
= "scons-poweroff",
452 .data
= &scons_pwroff
,
453 .maxlen
= sizeof (int),
455 .proc_handler
= &proc_dointvec
,
458 #ifdef CONFIG_SPARC64
460 .ctl_name
= CTL_UNNUMBERED
,
461 .procname
= "tsb-ratio",
462 .data
= &sysctl_tsb_ratio
,
463 .maxlen
= sizeof (int),
465 .proc_handler
= &proc_dointvec
,
470 .ctl_name
= KERN_HPPA_PWRSW
,
471 .procname
= "soft-power",
472 .data
= &pwrsw_enabled
,
473 .maxlen
= sizeof (int),
475 .proc_handler
= &proc_dointvec
,
478 .ctl_name
= KERN_HPPA_UNALIGNED
,
479 .procname
= "unaligned-trap",
480 .data
= &unaligned_enabled
,
481 .maxlen
= sizeof (int),
483 .proc_handler
= &proc_dointvec
,
487 .ctl_name
= KERN_CTLALTDEL
,
488 .procname
= "ctrl-alt-del",
490 .maxlen
= sizeof(int),
492 .proc_handler
= &proc_dointvec
,
494 #ifdef CONFIG_FUNCTION_TRACER
496 .ctl_name
= CTL_UNNUMBERED
,
497 .procname
= "ftrace_enabled",
498 .data
= &ftrace_enabled
,
499 .maxlen
= sizeof(int),
501 .proc_handler
= &ftrace_enable_sysctl
,
504 #ifdef CONFIG_STACK_TRACER
506 .ctl_name
= CTL_UNNUMBERED
,
507 .procname
= "stack_tracer_enabled",
508 .data
= &stack_tracer_enabled
,
509 .maxlen
= sizeof(int),
511 .proc_handler
= &stack_trace_sysctl
,
514 #ifdef CONFIG_TRACING
516 .ctl_name
= CTL_UNNUMBERED
,
517 .procname
= "ftrace_dump_on_oops",
518 .data
= &ftrace_dump_on_oops
,
519 .maxlen
= sizeof(int),
521 .proc_handler
= &proc_dointvec
,
524 #ifdef CONFIG_MODULES
526 .ctl_name
= KERN_MODPROBE
,
527 .procname
= "modprobe",
528 .data
= &modprobe_path
,
529 .maxlen
= KMOD_PATH_LEN
,
531 .proc_handler
= &proc_dostring
,
532 .strategy
= &sysctl_string
,
535 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
537 .ctl_name
= KERN_HOTPLUG
,
538 .procname
= "hotplug",
539 .data
= &uevent_helper
,
540 .maxlen
= UEVENT_HELPER_PATH_LEN
,
542 .proc_handler
= &proc_dostring
,
543 .strategy
= &sysctl_string
,
546 #ifdef CONFIG_CHR_DEV_SG
548 .ctl_name
= KERN_SG_BIG_BUFF
,
549 .procname
= "sg-big-buff",
550 .data
= &sg_big_buff
,
551 .maxlen
= sizeof (int),
553 .proc_handler
= &proc_dointvec
,
556 #ifdef CONFIG_BSD_PROCESS_ACCT
558 .ctl_name
= KERN_ACCT
,
561 .maxlen
= 3*sizeof(int),
563 .proc_handler
= &proc_dointvec
,
566 #ifdef CONFIG_MAGIC_SYSRQ
568 .ctl_name
= KERN_SYSRQ
,
570 .data
= &__sysrq_enabled
,
571 .maxlen
= sizeof (int),
573 .proc_handler
= &proc_dointvec
,
576 #ifdef CONFIG_PROC_SYSCTL
578 .procname
= "cad_pid",
580 .maxlen
= sizeof (int),
582 .proc_handler
= &proc_do_cad_pid
,
586 .ctl_name
= KERN_MAX_THREADS
,
587 .procname
= "threads-max",
588 .data
= &max_threads
,
589 .maxlen
= sizeof(int),
591 .proc_handler
= &proc_dointvec
,
594 .ctl_name
= KERN_RANDOM
,
595 .procname
= "random",
597 .child
= random_table
,
600 .ctl_name
= KERN_OVERFLOWUID
,
601 .procname
= "overflowuid",
602 .data
= &overflowuid
,
603 .maxlen
= sizeof(int),
605 .proc_handler
= &proc_dointvec_minmax
,
606 .strategy
= &sysctl_intvec
,
607 .extra1
= &minolduid
,
608 .extra2
= &maxolduid
,
611 .ctl_name
= KERN_OVERFLOWGID
,
612 .procname
= "overflowgid",
613 .data
= &overflowgid
,
614 .maxlen
= sizeof(int),
616 .proc_handler
= &proc_dointvec_minmax
,
617 .strategy
= &sysctl_intvec
,
618 .extra1
= &minolduid
,
619 .extra2
= &maxolduid
,
622 #ifdef CONFIG_MATHEMU
624 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
625 .procname
= "ieee_emulation_warnings",
626 .data
= &sysctl_ieee_emulation_warnings
,
627 .maxlen
= sizeof(int),
629 .proc_handler
= &proc_dointvec
,
633 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
634 .procname
= "userprocess_debug",
635 .data
= &sysctl_userprocess_debug
,
636 .maxlen
= sizeof(int),
638 .proc_handler
= &proc_dointvec
,
642 .ctl_name
= KERN_PIDMAX
,
643 .procname
= "pid_max",
645 .maxlen
= sizeof (int),
647 .proc_handler
= &proc_dointvec_minmax
,
648 .strategy
= sysctl_intvec
,
649 .extra1
= &pid_max_min
,
650 .extra2
= &pid_max_max
,
653 .ctl_name
= KERN_PANIC_ON_OOPS
,
654 .procname
= "panic_on_oops",
655 .data
= &panic_on_oops
,
656 .maxlen
= sizeof(int),
658 .proc_handler
= &proc_dointvec
,
660 #if defined CONFIG_PRINTK
662 .ctl_name
= KERN_PRINTK
,
663 .procname
= "printk",
664 .data
= &console_loglevel
,
665 .maxlen
= 4*sizeof(int),
667 .proc_handler
= &proc_dointvec
,
670 .ctl_name
= KERN_PRINTK_RATELIMIT
,
671 .procname
= "printk_ratelimit",
672 .data
= &printk_ratelimit_state
.interval
,
673 .maxlen
= sizeof(int),
675 .proc_handler
= &proc_dointvec_jiffies
,
676 .strategy
= &sysctl_jiffies
,
679 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
680 .procname
= "printk_ratelimit_burst",
681 .data
= &printk_ratelimit_state
.burst
,
682 .maxlen
= sizeof(int),
684 .proc_handler
= &proc_dointvec
,
688 .ctl_name
= KERN_NGROUPS_MAX
,
689 .procname
= "ngroups_max",
690 .data
= &ngroups_max
,
691 .maxlen
= sizeof (int),
693 .proc_handler
= &proc_dointvec
,
695 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
697 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
698 .procname
= "unknown_nmi_panic",
699 .data
= &unknown_nmi_panic
,
700 .maxlen
= sizeof (int),
702 .proc_handler
= &proc_dointvec
,
705 .procname
= "nmi_watchdog",
706 .data
= &nmi_watchdog_enabled
,
707 .maxlen
= sizeof (int),
709 .proc_handler
= &proc_nmi_enabled
,
712 #if defined(CONFIG_X86)
714 .ctl_name
= KERN_PANIC_ON_NMI
,
715 .procname
= "panic_on_unrecovered_nmi",
716 .data
= &panic_on_unrecovered_nmi
,
717 .maxlen
= sizeof(int),
719 .proc_handler
= &proc_dointvec
,
722 .ctl_name
= KERN_BOOTLOADER_TYPE
,
723 .procname
= "bootloader_type",
724 .data
= &bootloader_type
,
725 .maxlen
= sizeof (int),
727 .proc_handler
= &proc_dointvec
,
730 .ctl_name
= CTL_UNNUMBERED
,
731 .procname
= "kstack_depth_to_print",
732 .data
= &kstack_depth_to_print
,
733 .maxlen
= sizeof(int),
735 .proc_handler
= &proc_dointvec
,
738 .ctl_name
= CTL_UNNUMBERED
,
739 .procname
= "io_delay_type",
740 .data
= &io_delay_type
,
741 .maxlen
= sizeof(int),
743 .proc_handler
= &proc_dointvec
,
746 #if defined(CONFIG_MMU)
748 .ctl_name
= KERN_RANDOMIZE
,
749 .procname
= "randomize_va_space",
750 .data
= &randomize_va_space
,
751 .maxlen
= sizeof(int),
753 .proc_handler
= &proc_dointvec
,
756 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
758 .ctl_name
= KERN_SPIN_RETRY
,
759 .procname
= "spin_retry",
761 .maxlen
= sizeof (int),
763 .proc_handler
= &proc_dointvec
,
766 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
768 .procname
= "acpi_video_flags",
769 .data
= &acpi_realmode_flags
,
770 .maxlen
= sizeof (unsigned long),
772 .proc_handler
= &proc_doulongvec_minmax
,
777 .ctl_name
= KERN_IA64_UNALIGNED
,
778 .procname
= "ignore-unaligned-usertrap",
779 .data
= &no_unaligned_warning
,
780 .maxlen
= sizeof (int),
782 .proc_handler
= &proc_dointvec
,
785 #ifdef CONFIG_DETECT_SOFTLOCKUP
787 .ctl_name
= CTL_UNNUMBERED
,
788 .procname
= "softlockup_panic",
789 .data
= &softlockup_panic
,
790 .maxlen
= sizeof(int),
792 .proc_handler
= &proc_dointvec_minmax
,
793 .strategy
= &sysctl_intvec
,
798 .ctl_name
= CTL_UNNUMBERED
,
799 .procname
= "softlockup_thresh",
800 .data
= &softlockup_thresh
,
801 .maxlen
= sizeof(int),
803 .proc_handler
= &proc_dointvec_minmax
,
804 .strategy
= &sysctl_intvec
,
809 .ctl_name
= CTL_UNNUMBERED
,
810 .procname
= "hung_task_check_count",
811 .data
= &sysctl_hung_task_check_count
,
812 .maxlen
= sizeof(unsigned long),
814 .proc_handler
= &proc_doulongvec_minmax
,
815 .strategy
= &sysctl_intvec
,
818 .ctl_name
= CTL_UNNUMBERED
,
819 .procname
= "hung_task_timeout_secs",
820 .data
= &sysctl_hung_task_timeout_secs
,
821 .maxlen
= sizeof(unsigned long),
823 .proc_handler
= &proc_doulongvec_minmax
,
824 .strategy
= &sysctl_intvec
,
827 .ctl_name
= CTL_UNNUMBERED
,
828 .procname
= "hung_task_warnings",
829 .data
= &sysctl_hung_task_warnings
,
830 .maxlen
= sizeof(unsigned long),
832 .proc_handler
= &proc_doulongvec_minmax
,
833 .strategy
= &sysctl_intvec
,
838 .ctl_name
= KERN_COMPAT_LOG
,
839 .procname
= "compat-log",
841 .maxlen
= sizeof (int),
843 .proc_handler
= &proc_dointvec
,
846 #ifdef CONFIG_RT_MUTEXES
848 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
849 .procname
= "max_lock_depth",
850 .data
= &max_lock_depth
,
851 .maxlen
= sizeof(int),
853 .proc_handler
= &proc_dointvec
,
857 .ctl_name
= CTL_UNNUMBERED
,
858 .procname
= "poweroff_cmd",
859 .data
= &poweroff_cmd
,
860 .maxlen
= POWEROFF_CMD_PATH_LEN
,
862 .proc_handler
= &proc_dostring
,
863 .strategy
= &sysctl_string
,
867 .ctl_name
= CTL_UNNUMBERED
,
870 .child
= key_sysctls
,
873 #ifdef CONFIG_RCU_TORTURE_TEST
875 .ctl_name
= CTL_UNNUMBERED
,
876 .procname
= "rcutorture_runnable",
877 .data
= &rcutorture_runnable
,
878 .maxlen
= sizeof(int),
880 .proc_handler
= &proc_dointvec
,
883 #ifdef CONFIG_UNEVICTABLE_LRU
885 .ctl_name
= CTL_UNNUMBERED
,
886 .procname
= "scan_unevictable_pages",
887 .data
= &scan_unevictable_pages
,
888 .maxlen
= sizeof(scan_unevictable_pages
),
890 .proc_handler
= &scan_unevictable_handler
,
894 * NOTE: do not add new entries to this table unless you have read
895 * Documentation/sysctl/ctl_unnumbered.txt
900 static struct ctl_table vm_table
[] = {
902 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
903 .procname
= "overcommit_memory",
904 .data
= &sysctl_overcommit_memory
,
905 .maxlen
= sizeof(sysctl_overcommit_memory
),
907 .proc_handler
= &proc_dointvec
,
910 .ctl_name
= VM_PANIC_ON_OOM
,
911 .procname
= "panic_on_oom",
912 .data
= &sysctl_panic_on_oom
,
913 .maxlen
= sizeof(sysctl_panic_on_oom
),
915 .proc_handler
= &proc_dointvec
,
918 .ctl_name
= CTL_UNNUMBERED
,
919 .procname
= "oom_kill_allocating_task",
920 .data
= &sysctl_oom_kill_allocating_task
,
921 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
923 .proc_handler
= &proc_dointvec
,
926 .ctl_name
= CTL_UNNUMBERED
,
927 .procname
= "oom_dump_tasks",
928 .data
= &sysctl_oom_dump_tasks
,
929 .maxlen
= sizeof(sysctl_oom_dump_tasks
),
931 .proc_handler
= &proc_dointvec
,
934 .ctl_name
= VM_OVERCOMMIT_RATIO
,
935 .procname
= "overcommit_ratio",
936 .data
= &sysctl_overcommit_ratio
,
937 .maxlen
= sizeof(sysctl_overcommit_ratio
),
939 .proc_handler
= &proc_dointvec
,
942 .ctl_name
= VM_PAGE_CLUSTER
,
943 .procname
= "page-cluster",
944 .data
= &page_cluster
,
945 .maxlen
= sizeof(int),
947 .proc_handler
= &proc_dointvec
,
950 .ctl_name
= VM_DIRTY_BACKGROUND
,
951 .procname
= "dirty_background_ratio",
952 .data
= &dirty_background_ratio
,
953 .maxlen
= sizeof(dirty_background_ratio
),
955 .proc_handler
= &proc_dointvec_minmax
,
956 .strategy
= &sysctl_intvec
,
958 .extra2
= &one_hundred
,
961 .ctl_name
= VM_DIRTY_RATIO
,
962 .procname
= "dirty_ratio",
963 .data
= &vm_dirty_ratio
,
964 .maxlen
= sizeof(vm_dirty_ratio
),
966 .proc_handler
= &dirty_ratio_handler
,
967 .strategy
= &sysctl_intvec
,
969 .extra2
= &one_hundred
,
972 .procname
= "dirty_writeback_centisecs",
973 .data
= &dirty_writeback_interval
,
974 .maxlen
= sizeof(dirty_writeback_interval
),
976 .proc_handler
= &dirty_writeback_centisecs_handler
,
979 .procname
= "dirty_expire_centisecs",
980 .data
= &dirty_expire_interval
,
981 .maxlen
= sizeof(dirty_expire_interval
),
983 .proc_handler
= &proc_dointvec_userhz_jiffies
,
986 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
987 .procname
= "nr_pdflush_threads",
988 .data
= &nr_pdflush_threads
,
989 .maxlen
= sizeof nr_pdflush_threads
,
990 .mode
= 0444 /* read-only*/,
991 .proc_handler
= &proc_dointvec
,
994 .ctl_name
= VM_SWAPPINESS
,
995 .procname
= "swappiness",
996 .data
= &vm_swappiness
,
997 .maxlen
= sizeof(vm_swappiness
),
999 .proc_handler
= &proc_dointvec_minmax
,
1000 .strategy
= &sysctl_intvec
,
1002 .extra2
= &one_hundred
,
1004 #ifdef CONFIG_HUGETLB_PAGE
1006 .procname
= "nr_hugepages",
1008 .maxlen
= sizeof(unsigned long),
1010 .proc_handler
= &hugetlb_sysctl_handler
,
1011 .extra1
= (void *)&hugetlb_zero
,
1012 .extra2
= (void *)&hugetlb_infinity
,
1015 .ctl_name
= VM_HUGETLB_GROUP
,
1016 .procname
= "hugetlb_shm_group",
1017 .data
= &sysctl_hugetlb_shm_group
,
1018 .maxlen
= sizeof(gid_t
),
1020 .proc_handler
= &proc_dointvec
,
1023 .ctl_name
= CTL_UNNUMBERED
,
1024 .procname
= "hugepages_treat_as_movable",
1025 .data
= &hugepages_treat_as_movable
,
1026 .maxlen
= sizeof(int),
1028 .proc_handler
= &hugetlb_treat_movable_handler
,
1031 .ctl_name
= CTL_UNNUMBERED
,
1032 .procname
= "nr_overcommit_hugepages",
1034 .maxlen
= sizeof(unsigned long),
1036 .proc_handler
= &hugetlb_overcommit_handler
,
1037 .extra1
= (void *)&hugetlb_zero
,
1038 .extra2
= (void *)&hugetlb_infinity
,
1042 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
1043 .procname
= "lowmem_reserve_ratio",
1044 .data
= &sysctl_lowmem_reserve_ratio
,
1045 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
1047 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
1048 .strategy
= &sysctl_intvec
,
1051 .ctl_name
= VM_DROP_PAGECACHE
,
1052 .procname
= "drop_caches",
1053 .data
= &sysctl_drop_caches
,
1054 .maxlen
= sizeof(int),
1056 .proc_handler
= drop_caches_sysctl_handler
,
1057 .strategy
= &sysctl_intvec
,
1060 .ctl_name
= VM_MIN_FREE_KBYTES
,
1061 .procname
= "min_free_kbytes",
1062 .data
= &min_free_kbytes
,
1063 .maxlen
= sizeof(min_free_kbytes
),
1065 .proc_handler
= &min_free_kbytes_sysctl_handler
,
1066 .strategy
= &sysctl_intvec
,
1070 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
1071 .procname
= "percpu_pagelist_fraction",
1072 .data
= &percpu_pagelist_fraction
,
1073 .maxlen
= sizeof(percpu_pagelist_fraction
),
1075 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
1076 .strategy
= &sysctl_intvec
,
1077 .extra1
= &min_percpu_pagelist_fract
,
1081 .ctl_name
= VM_MAX_MAP_COUNT
,
1082 .procname
= "max_map_count",
1083 .data
= &sysctl_max_map_count
,
1084 .maxlen
= sizeof(sysctl_max_map_count
),
1086 .proc_handler
= &proc_dointvec
1090 .ctl_name
= VM_LAPTOP_MODE
,
1091 .procname
= "laptop_mode",
1092 .data
= &laptop_mode
,
1093 .maxlen
= sizeof(laptop_mode
),
1095 .proc_handler
= &proc_dointvec_jiffies
,
1096 .strategy
= &sysctl_jiffies
,
1099 .ctl_name
= VM_BLOCK_DUMP
,
1100 .procname
= "block_dump",
1101 .data
= &block_dump
,
1102 .maxlen
= sizeof(block_dump
),
1104 .proc_handler
= &proc_dointvec
,
1105 .strategy
= &sysctl_intvec
,
1109 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
1110 .procname
= "vfs_cache_pressure",
1111 .data
= &sysctl_vfs_cache_pressure
,
1112 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
1114 .proc_handler
= &proc_dointvec
,
1115 .strategy
= &sysctl_intvec
,
1118 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1120 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
1121 .procname
= "legacy_va_layout",
1122 .data
= &sysctl_legacy_va_layout
,
1123 .maxlen
= sizeof(sysctl_legacy_va_layout
),
1125 .proc_handler
= &proc_dointvec
,
1126 .strategy
= &sysctl_intvec
,
1132 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
1133 .procname
= "zone_reclaim_mode",
1134 .data
= &zone_reclaim_mode
,
1135 .maxlen
= sizeof(zone_reclaim_mode
),
1137 .proc_handler
= &proc_dointvec
,
1138 .strategy
= &sysctl_intvec
,
1142 .ctl_name
= VM_MIN_UNMAPPED
,
1143 .procname
= "min_unmapped_ratio",
1144 .data
= &sysctl_min_unmapped_ratio
,
1145 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1147 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
1148 .strategy
= &sysctl_intvec
,
1150 .extra2
= &one_hundred
,
1153 .ctl_name
= VM_MIN_SLAB
,
1154 .procname
= "min_slab_ratio",
1155 .data
= &sysctl_min_slab_ratio
,
1156 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1158 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
1159 .strategy
= &sysctl_intvec
,
1161 .extra2
= &one_hundred
,
1166 .ctl_name
= CTL_UNNUMBERED
,
1167 .procname
= "stat_interval",
1168 .data
= &sysctl_stat_interval
,
1169 .maxlen
= sizeof(sysctl_stat_interval
),
1171 .proc_handler
= &proc_dointvec_jiffies
,
1172 .strategy
= &sysctl_jiffies
,
1175 #ifdef CONFIG_SECURITY
1177 .ctl_name
= CTL_UNNUMBERED
,
1178 .procname
= "mmap_min_addr",
1179 .data
= &mmap_min_addr
,
1180 .maxlen
= sizeof(unsigned long),
1182 .proc_handler
= &proc_doulongvec_minmax
,
1187 .ctl_name
= CTL_UNNUMBERED
,
1188 .procname
= "numa_zonelist_order",
1189 .data
= &numa_zonelist_order
,
1190 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1192 .proc_handler
= &numa_zonelist_order_handler
,
1193 .strategy
= &sysctl_string
,
1196 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1197 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1199 .ctl_name
= VM_VDSO_ENABLED
,
1200 .procname
= "vdso_enabled",
1201 .data
= &vdso_enabled
,
1202 .maxlen
= sizeof(vdso_enabled
),
1204 .proc_handler
= &proc_dointvec
,
1205 .strategy
= &sysctl_intvec
,
1209 #ifdef CONFIG_HIGHMEM
1211 .ctl_name
= CTL_UNNUMBERED
,
1212 .procname
= "highmem_is_dirtyable",
1213 .data
= &vm_highmem_is_dirtyable
,
1214 .maxlen
= sizeof(vm_highmem_is_dirtyable
),
1216 .proc_handler
= &proc_dointvec_minmax
,
1217 .strategy
= &sysctl_intvec
,
1223 * NOTE: do not add new entries to this table unless you have read
1224 * Documentation/sysctl/ctl_unnumbered.txt
1229 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1230 static struct ctl_table binfmt_misc_table
[] = {
1235 static struct ctl_table fs_table
[] = {
1237 .ctl_name
= FS_NRINODE
,
1238 .procname
= "inode-nr",
1239 .data
= &inodes_stat
,
1240 .maxlen
= 2*sizeof(int),
1242 .proc_handler
= &proc_dointvec
,
1245 .ctl_name
= FS_STATINODE
,
1246 .procname
= "inode-state",
1247 .data
= &inodes_stat
,
1248 .maxlen
= 7*sizeof(int),
1250 .proc_handler
= &proc_dointvec
,
1253 .procname
= "file-nr",
1254 .data
= &files_stat
,
1255 .maxlen
= 3*sizeof(int),
1257 .proc_handler
= &proc_nr_files
,
1260 .ctl_name
= FS_MAXFILE
,
1261 .procname
= "file-max",
1262 .data
= &files_stat
.max_files
,
1263 .maxlen
= sizeof(int),
1265 .proc_handler
= &proc_dointvec
,
1268 .ctl_name
= CTL_UNNUMBERED
,
1269 .procname
= "nr_open",
1270 .data
= &sysctl_nr_open
,
1271 .maxlen
= sizeof(int),
1273 .proc_handler
= &proc_dointvec_minmax
,
1274 .extra1
= &sysctl_nr_open_min
,
1275 .extra2
= &sysctl_nr_open_max
,
1278 .ctl_name
= FS_DENTRY
,
1279 .procname
= "dentry-state",
1280 .data
= &dentry_stat
,
1281 .maxlen
= 6*sizeof(int),
1283 .proc_handler
= &proc_dointvec
,
1286 .ctl_name
= FS_OVERFLOWUID
,
1287 .procname
= "overflowuid",
1288 .data
= &fs_overflowuid
,
1289 .maxlen
= sizeof(int),
1291 .proc_handler
= &proc_dointvec_minmax
,
1292 .strategy
= &sysctl_intvec
,
1293 .extra1
= &minolduid
,
1294 .extra2
= &maxolduid
,
1297 .ctl_name
= FS_OVERFLOWGID
,
1298 .procname
= "overflowgid",
1299 .data
= &fs_overflowgid
,
1300 .maxlen
= sizeof(int),
1302 .proc_handler
= &proc_dointvec_minmax
,
1303 .strategy
= &sysctl_intvec
,
1304 .extra1
= &minolduid
,
1305 .extra2
= &maxolduid
,
1307 #ifdef CONFIG_FILE_LOCKING
1309 .ctl_name
= FS_LEASES
,
1310 .procname
= "leases-enable",
1311 .data
= &leases_enable
,
1312 .maxlen
= sizeof(int),
1314 .proc_handler
= &proc_dointvec
,
1317 #ifdef CONFIG_DNOTIFY
1319 .ctl_name
= FS_DIR_NOTIFY
,
1320 .procname
= "dir-notify-enable",
1321 .data
= &dir_notify_enable
,
1322 .maxlen
= sizeof(int),
1324 .proc_handler
= &proc_dointvec
,
1328 #ifdef CONFIG_FILE_LOCKING
1330 .ctl_name
= FS_LEASE_TIME
,
1331 .procname
= "lease-break-time",
1332 .data
= &lease_break_time
,
1333 .maxlen
= sizeof(int),
1335 .proc_handler
= &proc_dointvec_minmax
,
1336 .strategy
= &sysctl_intvec
,
1343 .procname
= "aio-nr",
1345 .maxlen
= sizeof(aio_nr
),
1347 .proc_handler
= &proc_doulongvec_minmax
,
1350 .procname
= "aio-max-nr",
1351 .data
= &aio_max_nr
,
1352 .maxlen
= sizeof(aio_max_nr
),
1354 .proc_handler
= &proc_doulongvec_minmax
,
1356 #endif /* CONFIG_AIO */
1357 #ifdef CONFIG_INOTIFY_USER
1359 .ctl_name
= FS_INOTIFY
,
1360 .procname
= "inotify",
1362 .child
= inotify_table
,
1367 .procname
= "epoll",
1369 .child
= epoll_table
,
1374 .ctl_name
= KERN_SETUID_DUMPABLE
,
1375 .procname
= "suid_dumpable",
1376 .data
= &suid_dumpable
,
1377 .maxlen
= sizeof(int),
1379 .proc_handler
= &proc_dointvec
,
1381 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1383 .ctl_name
= CTL_UNNUMBERED
,
1384 .procname
= "binfmt_misc",
1386 .child
= binfmt_misc_table
,
1390 * NOTE: do not add new entries to this table unless you have read
1391 * Documentation/sysctl/ctl_unnumbered.txt
1396 static struct ctl_table debug_table
[] = {
1397 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1399 .ctl_name
= CTL_UNNUMBERED
,
1400 .procname
= "exception-trace",
1401 .data
= &show_unhandled_signals
,
1402 .maxlen
= sizeof(int),
1404 .proc_handler
= proc_dointvec
1410 static struct ctl_table dev_table
[] = {
1414 static DEFINE_SPINLOCK(sysctl_lock
);
1416 /* called under sysctl_lock */
1417 static int use_table(struct ctl_table_header
*p
)
1419 if (unlikely(p
->unregistering
))
1425 /* called under sysctl_lock */
1426 static void unuse_table(struct ctl_table_header
*p
)
1429 if (unlikely(p
->unregistering
))
1430 complete(p
->unregistering
);
1433 /* called under sysctl_lock, will reacquire if has to wait */
1434 static void start_unregistering(struct ctl_table_header
*p
)
1437 * if p->used is 0, nobody will ever touch that entry again;
1438 * we'll eliminate all paths to it before dropping sysctl_lock
1440 if (unlikely(p
->used
)) {
1441 struct completion wait
;
1442 init_completion(&wait
);
1443 p
->unregistering
= &wait
;
1444 spin_unlock(&sysctl_lock
);
1445 wait_for_completion(&wait
);
1446 spin_lock(&sysctl_lock
);
1448 /* anything non-NULL; we'll never dereference it */
1449 p
->unregistering
= ERR_PTR(-EINVAL
);
1452 * do not remove from the list until nobody holds it; walking the
1453 * list in do_sysctl() relies on that.
1455 list_del_init(&p
->ctl_entry
);
1458 void sysctl_head_get(struct ctl_table_header
*head
)
1460 spin_lock(&sysctl_lock
);
1462 spin_unlock(&sysctl_lock
);
1465 void sysctl_head_put(struct ctl_table_header
*head
)
1467 spin_lock(&sysctl_lock
);
1470 spin_unlock(&sysctl_lock
);
1473 struct ctl_table_header
*sysctl_head_grab(struct ctl_table_header
*head
)
1477 spin_lock(&sysctl_lock
);
1478 if (!use_table(head
))
1479 head
= ERR_PTR(-ENOENT
);
1480 spin_unlock(&sysctl_lock
);
1484 void sysctl_head_finish(struct ctl_table_header
*head
)
1488 spin_lock(&sysctl_lock
);
1490 spin_unlock(&sysctl_lock
);
1493 static struct ctl_table_set
*
1494 lookup_header_set(struct ctl_table_root
*root
, struct nsproxy
*namespaces
)
1496 struct ctl_table_set
*set
= &root
->default_set
;
1498 set
= root
->lookup(root
, namespaces
);
1502 static struct list_head
*
1503 lookup_header_list(struct ctl_table_root
*root
, struct nsproxy
*namespaces
)
1505 struct ctl_table_set
*set
= lookup_header_set(root
, namespaces
);
1509 struct ctl_table_header
*__sysctl_head_next(struct nsproxy
*namespaces
,
1510 struct ctl_table_header
*prev
)
1512 struct ctl_table_root
*root
;
1513 struct list_head
*header_list
;
1514 struct ctl_table_header
*head
;
1515 struct list_head
*tmp
;
1517 spin_lock(&sysctl_lock
);
1520 tmp
= &prev
->ctl_entry
;
1524 tmp
= &root_table_header
.ctl_entry
;
1526 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1528 if (!use_table(head
))
1530 spin_unlock(&sysctl_lock
);
1535 header_list
= lookup_header_list(root
, namespaces
);
1536 if (tmp
!= header_list
)
1540 root
= list_entry(root
->root_list
.next
,
1541 struct ctl_table_root
, root_list
);
1542 if (root
== &sysctl_table_root
)
1544 header_list
= lookup_header_list(root
, namespaces
);
1545 } while (list_empty(header_list
));
1546 tmp
= header_list
->next
;
1549 spin_unlock(&sysctl_lock
);
1553 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1555 return __sysctl_head_next(current
->nsproxy
, prev
);
1558 void register_sysctl_root(struct ctl_table_root
*root
)
1560 spin_lock(&sysctl_lock
);
1561 list_add_tail(&root
->root_list
, &sysctl_table_root
.root_list
);
1562 spin_unlock(&sysctl_lock
);
1565 #ifdef CONFIG_SYSCTL_SYSCALL
1566 /* Perform the actual read/write of a sysctl table entry. */
1567 static int do_sysctl_strategy(struct ctl_table_root
*root
,
1568 struct ctl_table
*table
,
1569 void __user
*oldval
, size_t __user
*oldlenp
,
1570 void __user
*newval
, size_t newlen
)
1578 if (sysctl_perm(root
, table
, op
))
1581 if (table
->strategy
) {
1582 rc
= table
->strategy(table
, oldval
, oldlenp
, newval
, newlen
);
1589 /* If there is no strategy routine, or if the strategy returns
1590 * zero, proceed with automatic r/w */
1591 if (table
->data
&& table
->maxlen
) {
1592 rc
= sysctl_data(table
, oldval
, oldlenp
, newval
, newlen
);
1599 static int parse_table(int __user
*name
, int nlen
,
1600 void __user
*oldval
, size_t __user
*oldlenp
,
1601 void __user
*newval
, size_t newlen
,
1602 struct ctl_table_root
*root
,
1603 struct ctl_table
*table
)
1609 if (get_user(n
, name
))
1611 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1612 if (!table
->ctl_name
)
1614 if (n
== table
->ctl_name
) {
1617 if (sysctl_perm(root
, table
, MAY_EXEC
))
1621 table
= table
->child
;
1624 error
= do_sysctl_strategy(root
, table
,
1633 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1634 void __user
*newval
, size_t newlen
)
1636 struct ctl_table_header
*head
;
1637 int error
= -ENOTDIR
;
1639 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1643 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1647 for (head
= sysctl_head_next(NULL
); head
;
1648 head
= sysctl_head_next(head
)) {
1649 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1651 head
->root
, head
->ctl_table
);
1652 if (error
!= -ENOTDIR
) {
1653 sysctl_head_finish(head
);
1660 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1662 struct __sysctl_args tmp
;
1665 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1668 error
= deprecated_sysctl_warning(&tmp
);
1673 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1674 tmp
.newval
, tmp
.newlen
);
1679 #endif /* CONFIG_SYSCTL_SYSCALL */
1682 * sysctl_perm does NOT grant the superuser all rights automatically, because
1683 * some sysctl variables are readonly even to root.
1686 static int test_perm(int mode
, int op
)
1688 if (!current_euid())
1690 else if (in_egroup_p(0))
1692 if ((op
& ~mode
& (MAY_READ
|MAY_WRITE
|MAY_EXEC
)) == 0)
1697 int sysctl_perm(struct ctl_table_root
*root
, struct ctl_table
*table
, int op
)
1702 error
= security_sysctl(table
, op
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
));
1706 if (root
->permissions
)
1707 mode
= root
->permissions(root
, current
->nsproxy
, table
);
1711 return test_perm(mode
, op
);
1714 static void sysctl_set_parent(struct ctl_table
*parent
, struct ctl_table
*table
)
1716 for (; table
->ctl_name
|| table
->procname
; table
++) {
1717 table
->parent
= parent
;
1719 sysctl_set_parent(table
, table
->child
);
1723 static __init
int sysctl_init(void)
1725 sysctl_set_parent(NULL
, root_table
);
1726 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1729 err
= sysctl_check_table(current
->nsproxy
, root_table
);
1735 core_initcall(sysctl_init
);
1737 static struct ctl_table
*is_branch_in(struct ctl_table
*branch
,
1738 struct ctl_table
*table
)
1740 struct ctl_table
*p
;
1741 const char *s
= branch
->procname
;
1743 /* branch should have named subdirectory as its first element */
1744 if (!s
|| !branch
->child
)
1747 /* ... and nothing else */
1748 if (branch
[1].procname
|| branch
[1].ctl_name
)
1751 /* table should contain subdirectory with the same name */
1752 for (p
= table
; p
->procname
|| p
->ctl_name
; p
++) {
1755 if (p
->procname
&& strcmp(p
->procname
, s
) == 0)
1761 /* see if attaching q to p would be an improvement */
1762 static void try_attach(struct ctl_table_header
*p
, struct ctl_table_header
*q
)
1764 struct ctl_table
*to
= p
->ctl_table
, *by
= q
->ctl_table
;
1765 struct ctl_table
*next
;
1767 int not_in_parent
= !p
->attached_by
;
1769 while ((next
= is_branch_in(by
, to
)) != NULL
) {
1770 if (by
== q
->attached_by
)
1772 if (to
== p
->attached_by
)
1778 if (is_better
&& not_in_parent
) {
1779 q
->attached_by
= by
;
1780 q
->attached_to
= to
;
1786 * __register_sysctl_paths - register a sysctl hierarchy
1787 * @root: List of sysctl headers to register on
1788 * @namespaces: Data to compute which lists of sysctl entries are visible
1789 * @path: The path to the directory the sysctl table is in.
1790 * @table: the top-level table structure
1792 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1793 * array. A completely 0 filled entry terminates the table.
1795 * The members of the &struct ctl_table structure are used as follows:
1797 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1798 * must be unique within that level of sysctl
1800 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1801 * enter a sysctl file
1803 * data - a pointer to data for use by proc_handler
1805 * maxlen - the maximum size in bytes of the data
1807 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1809 * child - a pointer to the child sysctl table if this entry is a directory, or
1812 * proc_handler - the text handler routine (described below)
1814 * strategy - the strategy routine (described below)
1816 * de - for internal use by the sysctl routines
1818 * extra1, extra2 - extra pointers usable by the proc handler routines
1820 * Leaf nodes in the sysctl tree will be represented by a single file
1821 * under /proc; non-leaf nodes will be represented by directories.
1823 * sysctl(2) can automatically manage read and write requests through
1824 * the sysctl table. The data and maxlen fields of the ctl_table
1825 * struct enable minimal validation of the values being written to be
1826 * performed, and the mode field allows minimal authentication.
1828 * More sophisticated management can be enabled by the provision of a
1829 * strategy routine with the table entry. This will be called before
1830 * any automatic read or write of the data is performed.
1832 * The strategy routine may return
1834 * < 0 - Error occurred (error is passed to user process)
1836 * 0 - OK - proceed with automatic read or write.
1838 * > 0 - OK - read or write has been done by the strategy routine, so
1839 * return immediately.
1841 * There must be a proc_handler routine for any terminal nodes
1842 * mirrored under /proc/sys (non-terminals are handled by a built-in
1843 * directory handler). Several default handlers are available to
1844 * cover common cases -
1846 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1847 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1848 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1850 * It is the handler's job to read the input buffer from user memory
1851 * and process it. The handler should return 0 on success.
1853 * This routine returns %NULL on a failure to register, and a pointer
1854 * to the table header on success.
1856 struct ctl_table_header
*__register_sysctl_paths(
1857 struct ctl_table_root
*root
,
1858 struct nsproxy
*namespaces
,
1859 const struct ctl_path
*path
, struct ctl_table
*table
)
1861 struct ctl_table_header
*header
;
1862 struct ctl_table
*new, **prevp
;
1863 unsigned int n
, npath
;
1864 struct ctl_table_set
*set
;
1866 /* Count the path components */
1867 for (npath
= 0; path
[npath
].ctl_name
|| path
[npath
].procname
; ++npath
)
1871 * For each path component, allocate a 2-element ctl_table array.
1872 * The first array element will be filled with the sysctl entry
1873 * for this, the second will be the sentinel (ctl_name == 0).
1875 * We allocate everything in one go so that we don't have to
1876 * worry about freeing additional memory in unregister_sysctl_table.
1878 header
= kzalloc(sizeof(struct ctl_table_header
) +
1879 (2 * npath
* sizeof(struct ctl_table
)), GFP_KERNEL
);
1883 new = (struct ctl_table
*) (header
+ 1);
1885 /* Now connect the dots */
1886 prevp
= &header
->ctl_table
;
1887 for (n
= 0; n
< npath
; ++n
, ++path
) {
1888 /* Copy the procname */
1889 new->procname
= path
->procname
;
1890 new->ctl_name
= path
->ctl_name
;
1894 prevp
= &new->child
;
1899 header
->ctl_table_arg
= table
;
1901 INIT_LIST_HEAD(&header
->ctl_entry
);
1903 header
->unregistering
= NULL
;
1904 header
->root
= root
;
1905 sysctl_set_parent(NULL
, header
->ctl_table
);
1907 #ifdef CONFIG_SYSCTL_SYSCALL_CHECK
1908 if (sysctl_check_table(namespaces
, header
->ctl_table
)) {
1913 spin_lock(&sysctl_lock
);
1914 header
->set
= lookup_header_set(root
, namespaces
);
1915 header
->attached_by
= header
->ctl_table
;
1916 header
->attached_to
= root_table
;
1917 header
->parent
= &root_table_header
;
1918 for (set
= header
->set
; set
; set
= set
->parent
) {
1919 struct ctl_table_header
*p
;
1920 list_for_each_entry(p
, &set
->list
, ctl_entry
) {
1921 if (p
->unregistering
)
1923 try_attach(p
, header
);
1926 header
->parent
->count
++;
1927 list_add_tail(&header
->ctl_entry
, &header
->set
->list
);
1928 spin_unlock(&sysctl_lock
);
1934 * register_sysctl_table_path - register a sysctl table hierarchy
1935 * @path: The path to the directory the sysctl table is in.
1936 * @table: the top-level table structure
1938 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1939 * array. A completely 0 filled entry terminates the table.
1941 * See __register_sysctl_paths for more details.
1943 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
1944 struct ctl_table
*table
)
1946 return __register_sysctl_paths(&sysctl_table_root
, current
->nsproxy
,
1951 * register_sysctl_table - register a sysctl table hierarchy
1952 * @table: the top-level table structure
1954 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1955 * array. A completely 0 filled entry terminates the table.
1957 * See register_sysctl_paths for more details.
1959 struct ctl_table_header
*register_sysctl_table(struct ctl_table
*table
)
1961 static const struct ctl_path null_path
[] = { {} };
1963 return register_sysctl_paths(null_path
, table
);
1967 * unregister_sysctl_table - unregister a sysctl table hierarchy
1968 * @header: the header returned from register_sysctl_table
1970 * Unregisters the sysctl table and all children. proc entries may not
1971 * actually be removed until they are no longer used by anyone.
1973 void unregister_sysctl_table(struct ctl_table_header
* header
)
1980 spin_lock(&sysctl_lock
);
1981 start_unregistering(header
);
1982 if (!--header
->parent
->count
) {
1984 kfree(header
->parent
);
1986 if (!--header
->count
)
1988 spin_unlock(&sysctl_lock
);
1991 int sysctl_is_seen(struct ctl_table_header
*p
)
1993 struct ctl_table_set
*set
= p
->set
;
1995 spin_lock(&sysctl_lock
);
1996 if (p
->unregistering
)
1998 else if (!set
->is_seen
)
2001 res
= set
->is_seen(set
);
2002 spin_unlock(&sysctl_lock
);
2006 void setup_sysctl_set(struct ctl_table_set
*p
,
2007 struct ctl_table_set
*parent
,
2008 int (*is_seen
)(struct ctl_table_set
*))
2010 INIT_LIST_HEAD(&p
->list
);
2011 p
->parent
= parent
? parent
: &sysctl_table_root
.default_set
;
2012 p
->is_seen
= is_seen
;
2015 #else /* !CONFIG_SYSCTL */
2016 struct ctl_table_header
*register_sysctl_table(struct ctl_table
* table
)
2021 struct ctl_table_header
*register_sysctl_paths(const struct ctl_path
*path
,
2022 struct ctl_table
*table
)
2027 void unregister_sysctl_table(struct ctl_table_header
* table
)
2031 void setup_sysctl_set(struct ctl_table_set
*p
,
2032 struct ctl_table_set
*parent
,
2033 int (*is_seen
)(struct ctl_table_set
*))
2037 void sysctl_head_put(struct ctl_table_header
*head
)
2041 #endif /* CONFIG_SYSCTL */
2047 #ifdef CONFIG_PROC_SYSCTL
2049 static int _proc_do_string(void* data
, int maxlen
, int write
,
2050 struct file
*filp
, void __user
*buffer
,
2051 size_t *lenp
, loff_t
*ppos
)
2057 if (!data
|| !maxlen
|| !*lenp
) {
2065 while (len
< *lenp
) {
2066 if (get_user(c
, p
++))
2068 if (c
== 0 || c
== '\n')
2074 if(copy_from_user(data
, buffer
, len
))
2076 ((char *) data
)[len
] = 0;
2094 if(copy_to_user(buffer
, data
, len
))
2097 if(put_user('\n', ((char __user
*) buffer
) + len
))
2108 * proc_dostring - read a string sysctl
2109 * @table: the sysctl table
2110 * @write: %TRUE if this is a write to the sysctl file
2111 * @filp: the file structure
2112 * @buffer: the user buffer
2113 * @lenp: the size of the user buffer
2114 * @ppos: file position
2116 * Reads/writes a string from/to the user buffer. If the kernel
2117 * buffer provided is not large enough to hold the string, the
2118 * string is truncated. The copied string is %NULL-terminated.
2119 * If the string is being read by the user process, it is copied
2120 * and a newline '\n' is added. It is truncated if the buffer is
2123 * Returns 0 on success.
2125 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2126 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2128 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
2129 buffer
, lenp
, ppos
);
2133 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
2135 int write
, void *data
)
2138 *valp
= *negp
? -*lvalp
: *lvalp
;
2143 *lvalp
= (unsigned long)-val
;
2146 *lvalp
= (unsigned long)val
;
2152 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
2153 int write
, struct file
*filp
, void __user
*buffer
,
2154 size_t *lenp
, loff_t
*ppos
,
2155 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
2156 int write
, void *data
),
2159 #define TMPBUFLEN 21
2160 int *i
, vleft
, first
=1, neg
, val
;
2164 char buf
[TMPBUFLEN
], *p
;
2165 char __user
*s
= buffer
;
2167 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
2168 (*ppos
&& !write
)) {
2173 i
= (int *) tbl_data
;
2174 vleft
= table
->maxlen
/ sizeof(*i
);
2178 conv
= do_proc_dointvec_conv
;
2180 for (; left
&& vleft
--; i
++, first
=0) {
2195 if (len
> sizeof(buf
) - 1)
2196 len
= sizeof(buf
) - 1;
2197 if (copy_from_user(buf
, s
, len
))
2201 if (*p
== '-' && left
> 1) {
2205 if (*p
< '0' || *p
> '9')
2208 lval
= simple_strtoul(p
, &p
, 0);
2211 if ((len
< left
) && *p
&& !isspace(*p
))
2218 if (conv(&neg
, &lval
, i
, 1, data
))
2225 if (conv(&neg
, &lval
, i
, 0, data
))
2228 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
2232 if(copy_to_user(s
, buf
, len
))
2239 if (!write
&& !first
&& left
) {
2240 if(put_user('\n', s
))
2247 if (get_user(c
, s
++))
2262 static int do_proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2263 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
2264 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
2265 int write
, void *data
),
2268 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
2269 buffer
, lenp
, ppos
, conv
, data
);
2273 * proc_dointvec - read a vector of integers
2274 * @table: the sysctl table
2275 * @write: %TRUE if this is a write to the sysctl file
2276 * @filp: the file structure
2277 * @buffer: the user buffer
2278 * @lenp: the size of the user buffer
2279 * @ppos: file position
2281 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2282 * values from/to the user buffer, treated as an ASCII string.
2284 * Returns 0 on success.
2286 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2287 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2289 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2294 * Taint values can only be increased
2295 * This means we can safely use a temporary.
2297 static int proc_taint(struct ctl_table
*table
, int write
, struct file
*filp
,
2298 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2301 unsigned long tmptaint
= get_taint();
2304 if (write
&& !capable(CAP_SYS_ADMIN
))
2309 err
= proc_doulongvec_minmax(&t
, write
, filp
, buffer
, lenp
, ppos
);
2315 * Poor man's atomic or. Not worth adding a primitive
2316 * to everyone's atomic.h for this
2319 for (i
= 0; i
< BITS_PER_LONG
&& tmptaint
>> i
; i
++) {
2320 if ((tmptaint
>> i
) & 1)
2328 struct do_proc_dointvec_minmax_conv_param
{
2333 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
2335 int write
, void *data
)
2337 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
2339 int val
= *negp
? -*lvalp
: *lvalp
;
2340 if ((param
->min
&& *param
->min
> val
) ||
2341 (param
->max
&& *param
->max
< val
))
2348 *lvalp
= (unsigned long)-val
;
2351 *lvalp
= (unsigned long)val
;
2358 * proc_dointvec_minmax - read a vector of integers with min/max values
2359 * @table: the sysctl table
2360 * @write: %TRUE if this is a write to the sysctl file
2361 * @filp: the file structure
2362 * @buffer: the user buffer
2363 * @lenp: the size of the user buffer
2364 * @ppos: file position
2366 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2367 * values from/to the user buffer, treated as an ASCII string.
2369 * This routine will ensure the values are within the range specified by
2370 * table->extra1 (min) and table->extra2 (max).
2372 * Returns 0 on success.
2374 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2375 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2377 struct do_proc_dointvec_minmax_conv_param param
= {
2378 .min
= (int *) table
->extra1
,
2379 .max
= (int *) table
->extra2
,
2381 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2382 do_proc_dointvec_minmax_conv
, ¶m
);
2385 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
2387 void __user
*buffer
,
2388 size_t *lenp
, loff_t
*ppos
,
2389 unsigned long convmul
,
2390 unsigned long convdiv
)
2392 #define TMPBUFLEN 21
2393 unsigned long *i
, *min
, *max
, val
;
2394 int vleft
, first
=1, neg
;
2396 char buf
[TMPBUFLEN
], *p
;
2397 char __user
*s
= buffer
;
2399 if (!data
|| !table
->maxlen
|| !*lenp
||
2400 (*ppos
&& !write
)) {
2405 i
= (unsigned long *) data
;
2406 min
= (unsigned long *) table
->extra1
;
2407 max
= (unsigned long *) table
->extra2
;
2408 vleft
= table
->maxlen
/ sizeof(unsigned long);
2411 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
2426 if (len
> TMPBUFLEN
-1)
2428 if (copy_from_user(buf
, s
, len
))
2432 if (*p
== '-' && left
> 1) {
2436 if (*p
< '0' || *p
> '9')
2438 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
2440 if ((len
< left
) && *p
&& !isspace(*p
))
2449 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2456 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
2460 if(copy_to_user(s
, buf
, len
))
2467 if (!write
&& !first
&& left
) {
2468 if(put_user('\n', s
))
2475 if (get_user(c
, s
++))
2490 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2492 void __user
*buffer
,
2493 size_t *lenp
, loff_t
*ppos
,
2494 unsigned long convmul
,
2495 unsigned long convdiv
)
2497 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2498 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2502 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2503 * @table: the sysctl table
2504 * @write: %TRUE if this is a write to the sysctl file
2505 * @filp: the file structure
2506 * @buffer: the user buffer
2507 * @lenp: the size of the user buffer
2508 * @ppos: file position
2510 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2511 * values from/to the user buffer, treated as an ASCII string.
2513 * This routine will ensure the values are within the range specified by
2514 * table->extra1 (min) and table->extra2 (max).
2516 * Returns 0 on success.
2518 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2519 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2521 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2525 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2526 * @table: the sysctl table
2527 * @write: %TRUE if this is a write to the sysctl file
2528 * @filp: the file structure
2529 * @buffer: the user buffer
2530 * @lenp: the size of the user buffer
2531 * @ppos: file position
2533 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2534 * values from/to the user buffer, treated as an ASCII string. The values
2535 * are treated as milliseconds, and converted to jiffies when they are stored.
2537 * This routine will ensure the values are within the range specified by
2538 * table->extra1 (min) and table->extra2 (max).
2540 * Returns 0 on success.
2542 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2544 void __user
*buffer
,
2545 size_t *lenp
, loff_t
*ppos
)
2547 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2548 lenp
, ppos
, HZ
, 1000l);
2552 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2554 int write
, void *data
)
2557 if (*lvalp
> LONG_MAX
/ HZ
)
2559 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2565 lval
= (unsigned long)-val
;
2568 lval
= (unsigned long)val
;
2575 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2577 int write
, void *data
)
2580 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2582 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2588 lval
= (unsigned long)-val
;
2591 lval
= (unsigned long)val
;
2593 *lvalp
= jiffies_to_clock_t(lval
);
2598 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2600 int write
, void *data
)
2603 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2609 lval
= (unsigned long)-val
;
2612 lval
= (unsigned long)val
;
2614 *lvalp
= jiffies_to_msecs(lval
);
2620 * proc_dointvec_jiffies - read a vector of integers as seconds
2621 * @table: the sysctl table
2622 * @write: %TRUE if this is a write to the sysctl file
2623 * @filp: the file structure
2624 * @buffer: the user buffer
2625 * @lenp: the size of the user buffer
2626 * @ppos: file position
2628 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2629 * values from/to the user buffer, treated as an ASCII string.
2630 * The values read are assumed to be in seconds, and are converted into
2633 * Returns 0 on success.
2635 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2636 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2638 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2639 do_proc_dointvec_jiffies_conv
,NULL
);
2643 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2644 * @table: the sysctl table
2645 * @write: %TRUE if this is a write to the sysctl file
2646 * @filp: the file structure
2647 * @buffer: the user buffer
2648 * @lenp: the size of the user buffer
2649 * @ppos: pointer to the file position
2651 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2652 * values from/to the user buffer, treated as an ASCII string.
2653 * The values read are assumed to be in 1/USER_HZ seconds, and
2654 * are converted into jiffies.
2656 * Returns 0 on success.
2658 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2659 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2661 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2662 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2666 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2667 * @table: the sysctl table
2668 * @write: %TRUE if this is a write to the sysctl file
2669 * @filp: the file structure
2670 * @buffer: the user buffer
2671 * @lenp: the size of the user buffer
2672 * @ppos: file position
2673 * @ppos: the current position in the file
2675 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2676 * values from/to the user buffer, treated as an ASCII string.
2677 * The values read are assumed to be in 1/1000 seconds, and
2678 * are converted into jiffies.
2680 * Returns 0 on success.
2682 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2683 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2685 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2686 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2689 static int proc_do_cad_pid(struct ctl_table
*table
, int write
, struct file
*filp
,
2690 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2692 struct pid
*new_pid
;
2696 tmp
= pid_vnr(cad_pid
);
2698 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2699 lenp
, ppos
, NULL
, NULL
);
2703 new_pid
= find_get_pid(tmp
);
2707 put_pid(xchg(&cad_pid
, new_pid
));
2711 #else /* CONFIG_PROC_FS */
2713 int proc_dostring(struct ctl_table
*table
, int write
, struct file
*filp
,
2714 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2719 int proc_dointvec(struct ctl_table
*table
, int write
, struct file
*filp
,
2720 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2725 int proc_dointvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2726 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2731 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2732 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2737 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2738 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2743 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
, struct file
*filp
,
2744 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2749 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
, struct file
*filp
,
2750 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2755 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2757 void __user
*buffer
,
2758 size_t *lenp
, loff_t
*ppos
)
2764 #endif /* CONFIG_PROC_FS */
2767 #ifdef CONFIG_SYSCTL_SYSCALL
2769 * General sysctl support routines
2772 /* The generic sysctl data routine (used if no strategy routine supplied) */
2773 int sysctl_data(struct ctl_table
*table
,
2774 void __user
*oldval
, size_t __user
*oldlenp
,
2775 void __user
*newval
, size_t newlen
)
2779 /* Get out of I don't have a variable */
2780 if (!table
->data
|| !table
->maxlen
)
2783 if (oldval
&& oldlenp
) {
2784 if (get_user(len
, oldlenp
))
2787 if (len
> table
->maxlen
)
2788 len
= table
->maxlen
;
2789 if (copy_to_user(oldval
, table
->data
, len
))
2791 if (put_user(len
, oldlenp
))
2796 if (newval
&& newlen
) {
2797 if (newlen
> table
->maxlen
)
2798 newlen
= table
->maxlen
;
2800 if (copy_from_user(table
->data
, newval
, newlen
))
2806 /* The generic string strategy routine: */
2807 int sysctl_string(struct ctl_table
*table
,
2808 void __user
*oldval
, size_t __user
*oldlenp
,
2809 void __user
*newval
, size_t newlen
)
2811 if (!table
->data
|| !table
->maxlen
)
2814 if (oldval
&& oldlenp
) {
2816 if (get_user(bufsize
, oldlenp
))
2819 size_t len
= strlen(table
->data
), copied
;
2821 /* This shouldn't trigger for a well-formed sysctl */
2822 if (len
> table
->maxlen
)
2823 len
= table
->maxlen
;
2825 /* Copy up to a max of bufsize-1 bytes of the string */
2826 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2828 if (copy_to_user(oldval
, table
->data
, copied
) ||
2829 put_user(0, (char __user
*)(oldval
+ copied
)))
2831 if (put_user(len
, oldlenp
))
2835 if (newval
&& newlen
) {
2836 size_t len
= newlen
;
2837 if (len
> table
->maxlen
)
2838 len
= table
->maxlen
;
2839 if(copy_from_user(table
->data
, newval
, len
))
2841 if (len
== table
->maxlen
)
2843 ((char *) table
->data
)[len
] = 0;
2849 * This function makes sure that all of the integers in the vector
2850 * are between the minimum and maximum values given in the arrays
2851 * table->extra1 and table->extra2, respectively.
2853 int sysctl_intvec(struct ctl_table
*table
,
2854 void __user
*oldval
, size_t __user
*oldlenp
,
2855 void __user
*newval
, size_t newlen
)
2858 if (newval
&& newlen
) {
2859 int __user
*vec
= (int __user
*) newval
;
2860 int *min
= (int *) table
->extra1
;
2861 int *max
= (int *) table
->extra2
;
2865 if (newlen
% sizeof(int) != 0)
2868 if (!table
->extra1
&& !table
->extra2
)
2871 if (newlen
> table
->maxlen
)
2872 newlen
= table
->maxlen
;
2873 length
= newlen
/ sizeof(int);
2875 for (i
= 0; i
< length
; i
++) {
2877 if (get_user(value
, vec
+ i
))
2879 if (min
&& value
< min
[i
])
2881 if (max
&& value
> max
[i
])
2888 /* Strategy function to convert jiffies to seconds */
2889 int sysctl_jiffies(struct ctl_table
*table
,
2890 void __user
*oldval
, size_t __user
*oldlenp
,
2891 void __user
*newval
, size_t newlen
)
2893 if (oldval
&& oldlenp
) {
2896 if (get_user(olen
, oldlenp
))
2901 if (olen
< sizeof(int))
2904 val
= *(int *)(table
->data
) / HZ
;
2905 if (put_user(val
, (int __user
*)oldval
))
2907 if (put_user(sizeof(int), oldlenp
))
2911 if (newval
&& newlen
) {
2913 if (newlen
!= sizeof(int))
2915 if (get_user(new, (int __user
*)newval
))
2917 *(int *)(table
->data
) = new*HZ
;
2922 /* Strategy function to convert jiffies to seconds */
2923 int sysctl_ms_jiffies(struct ctl_table
*table
,
2924 void __user
*oldval
, size_t __user
*oldlenp
,
2925 void __user
*newval
, size_t newlen
)
2927 if (oldval
&& oldlenp
) {
2930 if (get_user(olen
, oldlenp
))
2935 if (olen
< sizeof(int))
2938 val
= jiffies_to_msecs(*(int *)(table
->data
));
2939 if (put_user(val
, (int __user
*)oldval
))
2941 if (put_user(sizeof(int), oldlenp
))
2945 if (newval
&& newlen
) {
2947 if (newlen
!= sizeof(int))
2949 if (get_user(new, (int __user
*)newval
))
2951 *(int *)(table
->data
) = msecs_to_jiffies(new);
2958 #else /* CONFIG_SYSCTL_SYSCALL */
2961 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2963 struct __sysctl_args tmp
;
2966 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2969 error
= deprecated_sysctl_warning(&tmp
);
2971 /* If no error reading the parameters then just -ENOSYS ... */
2978 int sysctl_data(struct ctl_table
*table
,
2979 void __user
*oldval
, size_t __user
*oldlenp
,
2980 void __user
*newval
, size_t newlen
)
2985 int sysctl_string(struct ctl_table
*table
,
2986 void __user
*oldval
, size_t __user
*oldlenp
,
2987 void __user
*newval
, size_t newlen
)
2992 int sysctl_intvec(struct ctl_table
*table
,
2993 void __user
*oldval
, size_t __user
*oldlenp
,
2994 void __user
*newval
, size_t newlen
)
2999 int sysctl_jiffies(struct ctl_table
*table
,
3000 void __user
*oldval
, size_t __user
*oldlenp
,
3001 void __user
*newval
, size_t newlen
)
3006 int sysctl_ms_jiffies(struct ctl_table
*table
,
3007 void __user
*oldval
, size_t __user
*oldlenp
,
3008 void __user
*newval
, size_t newlen
)
3013 #endif /* CONFIG_SYSCTL_SYSCALL */
3015 static int deprecated_sysctl_warning(struct __sysctl_args
*args
)
3017 static int msg_count
;
3018 int name
[CTL_MAXNAME
];
3021 /* Check args->nlen. */
3022 if (args
->nlen
< 0 || args
->nlen
> CTL_MAXNAME
)
3025 /* Read in the sysctl name for better debug message logging */
3026 for (i
= 0; i
< args
->nlen
; i
++)
3027 if (get_user(name
[i
], args
->name
+ i
))
3030 /* Ignore accesses to kernel.version */
3031 if ((args
->nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
3034 if (msg_count
< 5) {
3037 "warning: process `%s' used the deprecated sysctl "
3038 "system call with ", current
->comm
);
3039 for (i
= 0; i
< args
->nlen
; i
++)
3040 printk("%d.", name
[i
]);
3047 * No sense putting this after each symbol definition, twice,
3048 * exception granted :-)
3050 EXPORT_SYMBOL(proc_dointvec
);
3051 EXPORT_SYMBOL(proc_dointvec_jiffies
);
3052 EXPORT_SYMBOL(proc_dointvec_minmax
);
3053 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
3054 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
3055 EXPORT_SYMBOL(proc_dostring
);
3056 EXPORT_SYMBOL(proc_doulongvec_minmax
);
3057 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
3058 EXPORT_SYMBOL(register_sysctl_table
);
3059 EXPORT_SYMBOL(register_sysctl_paths
);
3060 EXPORT_SYMBOL(sysctl_intvec
);
3061 EXPORT_SYMBOL(sysctl_jiffies
);
3062 EXPORT_SYMBOL(sysctl_ms_jiffies
);
3063 EXPORT_SYMBOL(sysctl_string
);
3064 EXPORT_SYMBOL(sysctl_data
);
3065 EXPORT_SYMBOL(unregister_sysctl_table
);