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/bitmap.h>
27 #include <linux/signal.h>
28 #include <linux/printk.h>
29 #include <linux/proc_fs.h>
30 #include <linux/security.h>
31 #include <linux/ctype.h>
32 #include <linux/kmemcheck.h>
33 #include <linux/kmemleak.h>
35 #include <linux/init.h>
36 #include <linux/kernel.h>
37 #include <linux/kobject.h>
38 #include <linux/net.h>
39 #include <linux/sysrq.h>
40 #include <linux/highuid.h>
41 #include <linux/writeback.h>
42 #include <linux/ratelimit.h>
43 #include <linux/compaction.h>
44 #include <linux/hugetlb.h>
45 #include <linux/initrd.h>
46 #include <linux/key.h>
47 #include <linux/times.h>
48 #include <linux/limits.h>
49 #include <linux/dcache.h>
50 #include <linux/dnotify.h>
51 #include <linux/syscalls.h>
52 #include <linux/vmstat.h>
53 #include <linux/nfs_fs.h>
54 #include <linux/acpi.h>
55 #include <linux/reboot.h>
56 #include <linux/ftrace.h>
57 #include <linux/perf_event.h>
58 #include <linux/kprobes.h>
59 #include <linux/pipe_fs_i.h>
60 #include <linux/oom.h>
61 #include <linux/kmod.h>
62 #include <linux/capability.h>
63 #include <linux/binfmts.h>
64 #include <linux/sched/sysctl.h>
65 #include <linux/kexec.h>
67 #include <asm/uaccess.h>
68 #include <asm/processor.h>
72 #include <asm/stacktrace.h>
76 #include <asm/setup.h>
78 #ifdef CONFIG_BSD_PROCESS_ACCT
79 #include <linux/acct.h>
81 #ifdef CONFIG_RT_MUTEXES
82 #include <linux/rtmutex.h>
84 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
85 #include <linux/lockdep.h>
87 #ifdef CONFIG_CHR_DEV_SG
91 #ifdef CONFIG_LOCKUP_DETECTOR
92 #include <linux/nmi.h>
96 #if defined(CONFIG_SYSCTL)
98 /* External variables not in a header file. */
99 extern int max_threads
;
100 extern int suid_dumpable
;
101 #ifdef CONFIG_COREDUMP
102 extern int core_uses_pid
;
103 extern char core_pattern
[];
104 extern unsigned int core_pipe_limit
;
107 extern int pid_max_min
, pid_max_max
;
108 extern int percpu_pagelist_fraction
;
109 extern int compat_log
;
110 extern int latencytop_enabled
;
111 extern int sysctl_nr_open_min
, sysctl_nr_open_max
;
113 extern int sysctl_nr_trim_pages
;
116 /* Constants used for minimum and maximum */
117 #ifdef CONFIG_LOCKUP_DETECTOR
118 static int sixty
= 60;
121 static int __maybe_unused neg_one
= -1;
124 static int __maybe_unused one
= 1;
125 static int __maybe_unused two
= 2;
126 static int __maybe_unused four
= 4;
127 static unsigned long one_ul
= 1;
128 static int one_hundred
= 100;
130 static int ten_thousand
= 10000;
133 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
134 static unsigned long dirty_bytes_min
= 2 * PAGE_SIZE
;
136 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
137 static int maxolduid
= 65535;
138 static int minolduid
;
140 static int ngroups_max
= NGROUPS_MAX
;
141 static const int cap_last_cap
= CAP_LAST_CAP
;
143 /*this is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs */
144 #ifdef CONFIG_DETECT_HUNG_TASK
145 static unsigned long hung_task_timeout_max
= (LONG_MAX
/HZ
);
148 #ifdef CONFIG_INOTIFY_USER
149 #include <linux/inotify.h>
155 extern int pwrsw_enabled
;
158 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
159 extern int unaligned_enabled
;
163 extern int unaligned_dump_stack
;
166 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
167 extern int no_unaligned_warning
;
170 #ifdef CONFIG_PROC_SYSCTL
172 #define SYSCTL_WRITES_LEGACY -1
173 #define SYSCTL_WRITES_WARN 0
174 #define SYSCTL_WRITES_STRICT 1
176 static int sysctl_writes_strict
= SYSCTL_WRITES_WARN
;
178 static int proc_do_cad_pid(struct ctl_table
*table
, int write
,
179 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
180 static int proc_taint(struct ctl_table
*table
, int write
,
181 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
185 static int proc_dointvec_minmax_sysadmin(struct ctl_table
*table
, int write
,
186 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
189 static int proc_dointvec_minmax_coredump(struct ctl_table
*table
, int write
,
190 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
191 #ifdef CONFIG_COREDUMP
192 static int proc_dostring_coredump(struct ctl_table
*table
, int write
,
193 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
196 #ifdef CONFIG_MAGIC_SYSRQ
197 /* Note: sysrq code uses it's own private copy */
198 static int __sysrq_enabled
= CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE
;
200 static int sysrq_sysctl_handler(struct ctl_table
*table
, int write
,
201 void __user
*buffer
, size_t *lenp
,
206 error
= proc_dointvec(table
, write
, buffer
, lenp
, ppos
);
211 sysrq_toggle_support(__sysrq_enabled
);
218 static struct ctl_table kern_table
[];
219 static struct ctl_table vm_table
[];
220 static struct ctl_table fs_table
[];
221 static struct ctl_table debug_table
[];
222 static struct ctl_table dev_table
[];
223 extern struct ctl_table random_table
[];
225 extern struct ctl_table epoll_table
[];
228 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
229 int sysctl_legacy_va_layout
;
232 /* The default sysctl tables: */
234 static struct ctl_table sysctl_base_table
[] = {
236 .procname
= "kernel",
253 .child
= debug_table
,
263 #ifdef CONFIG_SCHED_DEBUG
264 static int min_sched_granularity_ns
= 100000; /* 100 usecs */
265 static int max_sched_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
266 static int min_wakeup_granularity_ns
; /* 0 usecs */
267 static int max_wakeup_granularity_ns
= NSEC_PER_SEC
; /* 1 second */
269 static int min_sched_tunable_scaling
= SCHED_TUNABLESCALING_NONE
;
270 static int max_sched_tunable_scaling
= SCHED_TUNABLESCALING_END
-1;
271 #endif /* CONFIG_SMP */
272 #endif /* CONFIG_SCHED_DEBUG */
274 #ifdef CONFIG_COMPACTION
275 static int min_extfrag_threshold
;
276 static int max_extfrag_threshold
= 1000;
279 static struct ctl_table kern_table
[] = {
281 .procname
= "sched_child_runs_first",
282 .data
= &sysctl_sched_child_runs_first
,
283 .maxlen
= sizeof(unsigned int),
285 .proc_handler
= proc_dointvec
,
287 #ifdef CONFIG_SCHED_DEBUG
289 .procname
= "sched_min_granularity_ns",
290 .data
= &sysctl_sched_min_granularity
,
291 .maxlen
= sizeof(unsigned int),
293 .proc_handler
= sched_proc_update_handler
,
294 .extra1
= &min_sched_granularity_ns
,
295 .extra2
= &max_sched_granularity_ns
,
298 .procname
= "sched_latency_ns",
299 .data
= &sysctl_sched_latency
,
300 .maxlen
= sizeof(unsigned int),
302 .proc_handler
= sched_proc_update_handler
,
303 .extra1
= &min_sched_granularity_ns
,
304 .extra2
= &max_sched_granularity_ns
,
307 .procname
= "sched_wakeup_granularity_ns",
308 .data
= &sysctl_sched_wakeup_granularity
,
309 .maxlen
= sizeof(unsigned int),
311 .proc_handler
= sched_proc_update_handler
,
312 .extra1
= &min_wakeup_granularity_ns
,
313 .extra2
= &max_wakeup_granularity_ns
,
317 .procname
= "sched_tunable_scaling",
318 .data
= &sysctl_sched_tunable_scaling
,
319 .maxlen
= sizeof(enum sched_tunable_scaling
),
321 .proc_handler
= sched_proc_update_handler
,
322 .extra1
= &min_sched_tunable_scaling
,
323 .extra2
= &max_sched_tunable_scaling
,
326 .procname
= "sched_migration_cost_ns",
327 .data
= &sysctl_sched_migration_cost
,
328 .maxlen
= sizeof(unsigned int),
330 .proc_handler
= proc_dointvec
,
333 .procname
= "sched_nr_migrate",
334 .data
= &sysctl_sched_nr_migrate
,
335 .maxlen
= sizeof(unsigned int),
337 .proc_handler
= proc_dointvec
,
340 .procname
= "sched_time_avg_ms",
341 .data
= &sysctl_sched_time_avg
,
342 .maxlen
= sizeof(unsigned int),
344 .proc_handler
= proc_dointvec
,
347 .procname
= "sched_shares_window_ns",
348 .data
= &sysctl_sched_shares_window
,
349 .maxlen
= sizeof(unsigned int),
351 .proc_handler
= proc_dointvec
,
354 .procname
= "timer_migration",
355 .data
= &sysctl_timer_migration
,
356 .maxlen
= sizeof(unsigned int),
358 .proc_handler
= proc_dointvec_minmax
,
362 #endif /* CONFIG_SMP */
363 #ifdef CONFIG_NUMA_BALANCING
365 .procname
= "numa_balancing_scan_delay_ms",
366 .data
= &sysctl_numa_balancing_scan_delay
,
367 .maxlen
= sizeof(unsigned int),
369 .proc_handler
= proc_dointvec
,
372 .procname
= "numa_balancing_scan_period_min_ms",
373 .data
= &sysctl_numa_balancing_scan_period_min
,
374 .maxlen
= sizeof(unsigned int),
376 .proc_handler
= proc_dointvec
,
379 .procname
= "numa_balancing_scan_period_max_ms",
380 .data
= &sysctl_numa_balancing_scan_period_max
,
381 .maxlen
= sizeof(unsigned int),
383 .proc_handler
= proc_dointvec
,
386 .procname
= "numa_balancing_scan_size_mb",
387 .data
= &sysctl_numa_balancing_scan_size
,
388 .maxlen
= sizeof(unsigned int),
390 .proc_handler
= proc_dointvec_minmax
,
394 .procname
= "numa_balancing",
395 .data
= NULL
, /* filled in by handler */
396 .maxlen
= sizeof(unsigned int),
398 .proc_handler
= sysctl_numa_balancing
,
402 #endif /* CONFIG_NUMA_BALANCING */
403 #endif /* CONFIG_SCHED_DEBUG */
405 .procname
= "sched_rt_period_us",
406 .data
= &sysctl_sched_rt_period
,
407 .maxlen
= sizeof(unsigned int),
409 .proc_handler
= sched_rt_handler
,
412 .procname
= "sched_rt_runtime_us",
413 .data
= &sysctl_sched_rt_runtime
,
414 .maxlen
= sizeof(int),
416 .proc_handler
= sched_rt_handler
,
419 .procname
= "sched_rr_timeslice_ms",
420 .data
= &sched_rr_timeslice
,
421 .maxlen
= sizeof(int),
423 .proc_handler
= sched_rr_handler
,
425 #ifdef CONFIG_SCHED_AUTOGROUP
427 .procname
= "sched_autogroup_enabled",
428 .data
= &sysctl_sched_autogroup_enabled
,
429 .maxlen
= sizeof(unsigned int),
431 .proc_handler
= proc_dointvec_minmax
,
436 #ifdef CONFIG_CFS_BANDWIDTH
438 .procname
= "sched_cfs_bandwidth_slice_us",
439 .data
= &sysctl_sched_cfs_bandwidth_slice
,
440 .maxlen
= sizeof(unsigned int),
442 .proc_handler
= proc_dointvec_minmax
,
446 #ifdef CONFIG_PROVE_LOCKING
448 .procname
= "prove_locking",
449 .data
= &prove_locking
,
450 .maxlen
= sizeof(int),
452 .proc_handler
= proc_dointvec
,
455 #ifdef CONFIG_LOCK_STAT
457 .procname
= "lock_stat",
459 .maxlen
= sizeof(int),
461 .proc_handler
= proc_dointvec
,
466 .data
= &panic_timeout
,
467 .maxlen
= sizeof(int),
469 .proc_handler
= proc_dointvec
,
471 #ifdef CONFIG_COREDUMP
473 .procname
= "core_uses_pid",
474 .data
= &core_uses_pid
,
475 .maxlen
= sizeof(int),
477 .proc_handler
= proc_dointvec
,
480 .procname
= "core_pattern",
481 .data
= core_pattern
,
482 .maxlen
= CORENAME_MAX_SIZE
,
484 .proc_handler
= proc_dostring_coredump
,
487 .procname
= "core_pipe_limit",
488 .data
= &core_pipe_limit
,
489 .maxlen
= sizeof(unsigned int),
491 .proc_handler
= proc_dointvec
,
494 #ifdef CONFIG_PROC_SYSCTL
496 .procname
= "tainted",
497 .maxlen
= sizeof(long),
499 .proc_handler
= proc_taint
,
502 .procname
= "sysctl_writes_strict",
503 .data
= &sysctl_writes_strict
,
504 .maxlen
= sizeof(int),
506 .proc_handler
= proc_dointvec_minmax
,
511 #ifdef CONFIG_LATENCYTOP
513 .procname
= "latencytop",
514 .data
= &latencytop_enabled
,
515 .maxlen
= sizeof(int),
517 .proc_handler
= proc_dointvec
,
520 #ifdef CONFIG_BLK_DEV_INITRD
522 .procname
= "real-root-dev",
523 .data
= &real_root_dev
,
524 .maxlen
= sizeof(int),
526 .proc_handler
= proc_dointvec
,
530 .procname
= "print-fatal-signals",
531 .data
= &print_fatal_signals
,
532 .maxlen
= sizeof(int),
534 .proc_handler
= proc_dointvec
,
538 .procname
= "reboot-cmd",
539 .data
= reboot_command
,
542 .proc_handler
= proc_dostring
,
545 .procname
= "stop-a",
546 .data
= &stop_a_enabled
,
547 .maxlen
= sizeof (int),
549 .proc_handler
= proc_dointvec
,
552 .procname
= "scons-poweroff",
553 .data
= &scons_pwroff
,
554 .maxlen
= sizeof (int),
556 .proc_handler
= proc_dointvec
,
559 #ifdef CONFIG_SPARC64
561 .procname
= "tsb-ratio",
562 .data
= &sysctl_tsb_ratio
,
563 .maxlen
= sizeof (int),
565 .proc_handler
= proc_dointvec
,
570 .procname
= "soft-power",
571 .data
= &pwrsw_enabled
,
572 .maxlen
= sizeof (int),
574 .proc_handler
= proc_dointvec
,
577 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
579 .procname
= "unaligned-trap",
580 .data
= &unaligned_enabled
,
581 .maxlen
= sizeof (int),
583 .proc_handler
= proc_dointvec
,
587 .procname
= "ctrl-alt-del",
589 .maxlen
= sizeof(int),
591 .proc_handler
= proc_dointvec
,
593 #ifdef CONFIG_FUNCTION_TRACER
595 .procname
= "ftrace_enabled",
596 .data
= &ftrace_enabled
,
597 .maxlen
= sizeof(int),
599 .proc_handler
= ftrace_enable_sysctl
,
602 #ifdef CONFIG_STACK_TRACER
604 .procname
= "stack_tracer_enabled",
605 .data
= &stack_tracer_enabled
,
606 .maxlen
= sizeof(int),
608 .proc_handler
= stack_trace_sysctl
,
611 #ifdef CONFIG_TRACING
613 .procname
= "ftrace_dump_on_oops",
614 .data
= &ftrace_dump_on_oops
,
615 .maxlen
= sizeof(int),
617 .proc_handler
= proc_dointvec
,
620 .procname
= "traceoff_on_warning",
621 .data
= &__disable_trace_on_warning
,
622 .maxlen
= sizeof(__disable_trace_on_warning
),
624 .proc_handler
= proc_dointvec
,
629 .procname
= "kexec_load_disabled",
630 .data
= &kexec_load_disabled
,
631 .maxlen
= sizeof(int),
633 /* only handle a transition from default "0" to "1" */
634 .proc_handler
= proc_dointvec_minmax
,
639 #ifdef CONFIG_MODULES
641 .procname
= "modprobe",
642 .data
= &modprobe_path
,
643 .maxlen
= KMOD_PATH_LEN
,
645 .proc_handler
= proc_dostring
,
648 .procname
= "modules_disabled",
649 .data
= &modules_disabled
,
650 .maxlen
= sizeof(int),
652 /* only handle a transition from default "0" to "1" */
653 .proc_handler
= proc_dointvec_minmax
,
658 #ifdef CONFIG_UEVENT_HELPER
660 .procname
= "hotplug",
661 .data
= &uevent_helper
,
662 .maxlen
= UEVENT_HELPER_PATH_LEN
,
664 .proc_handler
= proc_dostring
,
667 #ifdef CONFIG_CHR_DEV_SG
669 .procname
= "sg-big-buff",
670 .data
= &sg_big_buff
,
671 .maxlen
= sizeof (int),
673 .proc_handler
= proc_dointvec
,
676 #ifdef CONFIG_BSD_PROCESS_ACCT
680 .maxlen
= 3*sizeof(int),
682 .proc_handler
= proc_dointvec
,
685 #ifdef CONFIG_MAGIC_SYSRQ
688 .data
= &__sysrq_enabled
,
689 .maxlen
= sizeof (int),
691 .proc_handler
= sysrq_sysctl_handler
,
694 #ifdef CONFIG_PROC_SYSCTL
696 .procname
= "cad_pid",
698 .maxlen
= sizeof (int),
700 .proc_handler
= proc_do_cad_pid
,
704 .procname
= "threads-max",
705 .data
= &max_threads
,
706 .maxlen
= sizeof(int),
708 .proc_handler
= proc_dointvec
,
711 .procname
= "random",
713 .child
= random_table
,
716 .procname
= "usermodehelper",
718 .child
= usermodehelper_table
,
721 .procname
= "overflowuid",
722 .data
= &overflowuid
,
723 .maxlen
= sizeof(int),
725 .proc_handler
= proc_dointvec_minmax
,
726 .extra1
= &minolduid
,
727 .extra2
= &maxolduid
,
730 .procname
= "overflowgid",
731 .data
= &overflowgid
,
732 .maxlen
= sizeof(int),
734 .proc_handler
= proc_dointvec_minmax
,
735 .extra1
= &minolduid
,
736 .extra2
= &maxolduid
,
739 #ifdef CONFIG_MATHEMU
741 .procname
= "ieee_emulation_warnings",
742 .data
= &sysctl_ieee_emulation_warnings
,
743 .maxlen
= sizeof(int),
745 .proc_handler
= proc_dointvec
,
749 .procname
= "userprocess_debug",
750 .data
= &show_unhandled_signals
,
751 .maxlen
= sizeof(int),
753 .proc_handler
= proc_dointvec
,
757 .procname
= "pid_max",
759 .maxlen
= sizeof (int),
761 .proc_handler
= proc_dointvec_minmax
,
762 .extra1
= &pid_max_min
,
763 .extra2
= &pid_max_max
,
766 .procname
= "panic_on_oops",
767 .data
= &panic_on_oops
,
768 .maxlen
= sizeof(int),
770 .proc_handler
= proc_dointvec
,
772 #if defined CONFIG_PRINTK
774 .procname
= "printk",
775 .data
= &console_loglevel
,
776 .maxlen
= 4*sizeof(int),
778 .proc_handler
= proc_dointvec
,
781 .procname
= "printk_ratelimit",
782 .data
= &printk_ratelimit_state
.interval
,
783 .maxlen
= sizeof(int),
785 .proc_handler
= proc_dointvec_jiffies
,
788 .procname
= "printk_ratelimit_burst",
789 .data
= &printk_ratelimit_state
.burst
,
790 .maxlen
= sizeof(int),
792 .proc_handler
= proc_dointvec
,
795 .procname
= "printk_delay",
796 .data
= &printk_delay_msec
,
797 .maxlen
= sizeof(int),
799 .proc_handler
= proc_dointvec_minmax
,
801 .extra2
= &ten_thousand
,
804 .procname
= "dmesg_restrict",
805 .data
= &dmesg_restrict
,
806 .maxlen
= sizeof(int),
808 .proc_handler
= proc_dointvec_minmax_sysadmin
,
813 .procname
= "kptr_restrict",
814 .data
= &kptr_restrict
,
815 .maxlen
= sizeof(int),
817 .proc_handler
= proc_dointvec_minmax_sysadmin
,
823 .procname
= "ngroups_max",
824 .data
= &ngroups_max
,
825 .maxlen
= sizeof (int),
827 .proc_handler
= proc_dointvec
,
830 .procname
= "cap_last_cap",
831 .data
= (void *)&cap_last_cap
,
832 .maxlen
= sizeof(int),
834 .proc_handler
= proc_dointvec
,
836 #if defined(CONFIG_LOCKUP_DETECTOR)
838 .procname
= "watchdog",
839 .data
= &watchdog_user_enabled
,
840 .maxlen
= sizeof (int),
842 .proc_handler
= proc_dowatchdog
,
847 .procname
= "watchdog_thresh",
848 .data
= &watchdog_thresh
,
849 .maxlen
= sizeof(int),
851 .proc_handler
= proc_dowatchdog
,
856 .procname
= "softlockup_panic",
857 .data
= &softlockup_panic
,
858 .maxlen
= sizeof(int),
860 .proc_handler
= proc_dointvec_minmax
,
866 .procname
= "softlockup_all_cpu_backtrace",
867 .data
= &sysctl_softlockup_all_cpu_backtrace
,
868 .maxlen
= sizeof(int),
870 .proc_handler
= proc_dointvec_minmax
,
874 #endif /* CONFIG_SMP */
876 .procname
= "nmi_watchdog",
877 .data
= &watchdog_user_enabled
,
878 .maxlen
= sizeof (int),
880 .proc_handler
= proc_dowatchdog
,
885 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
887 .procname
= "unknown_nmi_panic",
888 .data
= &unknown_nmi_panic
,
889 .maxlen
= sizeof (int),
891 .proc_handler
= proc_dointvec
,
894 #if defined(CONFIG_X86)
896 .procname
= "panic_on_unrecovered_nmi",
897 .data
= &panic_on_unrecovered_nmi
,
898 .maxlen
= sizeof(int),
900 .proc_handler
= proc_dointvec
,
903 .procname
= "panic_on_io_nmi",
904 .data
= &panic_on_io_nmi
,
905 .maxlen
= sizeof(int),
907 .proc_handler
= proc_dointvec
,
909 #ifdef CONFIG_DEBUG_STACKOVERFLOW
911 .procname
= "panic_on_stackoverflow",
912 .data
= &sysctl_panic_on_stackoverflow
,
913 .maxlen
= sizeof(int),
915 .proc_handler
= proc_dointvec
,
919 .procname
= "bootloader_type",
920 .data
= &bootloader_type
,
921 .maxlen
= sizeof (int),
923 .proc_handler
= proc_dointvec
,
926 .procname
= "bootloader_version",
927 .data
= &bootloader_version
,
928 .maxlen
= sizeof (int),
930 .proc_handler
= proc_dointvec
,
933 .procname
= "kstack_depth_to_print",
934 .data
= &kstack_depth_to_print
,
935 .maxlen
= sizeof(int),
937 .proc_handler
= proc_dointvec
,
940 .procname
= "io_delay_type",
941 .data
= &io_delay_type
,
942 .maxlen
= sizeof(int),
944 .proc_handler
= proc_dointvec
,
947 #if defined(CONFIG_MMU)
949 .procname
= "randomize_va_space",
950 .data
= &randomize_va_space
,
951 .maxlen
= sizeof(int),
953 .proc_handler
= proc_dointvec
,
956 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
958 .procname
= "spin_retry",
960 .maxlen
= sizeof (int),
962 .proc_handler
= proc_dointvec
,
965 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
967 .procname
= "acpi_video_flags",
968 .data
= &acpi_realmode_flags
,
969 .maxlen
= sizeof (unsigned long),
971 .proc_handler
= proc_doulongvec_minmax
,
974 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
976 .procname
= "ignore-unaligned-usertrap",
977 .data
= &no_unaligned_warning
,
978 .maxlen
= sizeof (int),
980 .proc_handler
= proc_dointvec
,
985 .procname
= "unaligned-dump-stack",
986 .data
= &unaligned_dump_stack
,
987 .maxlen
= sizeof (int),
989 .proc_handler
= proc_dointvec
,
992 #ifdef CONFIG_DETECT_HUNG_TASK
994 .procname
= "hung_task_panic",
995 .data
= &sysctl_hung_task_panic
,
996 .maxlen
= sizeof(int),
998 .proc_handler
= proc_dointvec_minmax
,
1003 .procname
= "hung_task_check_count",
1004 .data
= &sysctl_hung_task_check_count
,
1005 .maxlen
= sizeof(int),
1007 .proc_handler
= proc_dointvec_minmax
,
1011 .procname
= "hung_task_timeout_secs",
1012 .data
= &sysctl_hung_task_timeout_secs
,
1013 .maxlen
= sizeof(unsigned long),
1015 .proc_handler
= proc_dohung_task_timeout_secs
,
1016 .extra2
= &hung_task_timeout_max
,
1019 .procname
= "hung_task_warnings",
1020 .data
= &sysctl_hung_task_warnings
,
1021 .maxlen
= sizeof(int),
1023 .proc_handler
= proc_dointvec_minmax
,
1027 #ifdef CONFIG_COMPAT
1029 .procname
= "compat-log",
1030 .data
= &compat_log
,
1031 .maxlen
= sizeof (int),
1033 .proc_handler
= proc_dointvec
,
1036 #ifdef CONFIG_RT_MUTEXES
1038 .procname
= "max_lock_depth",
1039 .data
= &max_lock_depth
,
1040 .maxlen
= sizeof(int),
1042 .proc_handler
= proc_dointvec
,
1046 .procname
= "poweroff_cmd",
1047 .data
= &poweroff_cmd
,
1048 .maxlen
= POWEROFF_CMD_PATH_LEN
,
1050 .proc_handler
= proc_dostring
,
1056 .child
= key_sysctls
,
1059 #ifdef CONFIG_PERF_EVENTS
1061 * User-space scripts rely on the existence of this file
1062 * as a feature check for perf_events being enabled.
1064 * So it's an ABI, do not remove!
1067 .procname
= "perf_event_paranoid",
1068 .data
= &sysctl_perf_event_paranoid
,
1069 .maxlen
= sizeof(sysctl_perf_event_paranoid
),
1071 .proc_handler
= proc_dointvec
,
1074 .procname
= "perf_event_mlock_kb",
1075 .data
= &sysctl_perf_event_mlock
,
1076 .maxlen
= sizeof(sysctl_perf_event_mlock
),
1078 .proc_handler
= proc_dointvec
,
1081 .procname
= "perf_event_max_sample_rate",
1082 .data
= &sysctl_perf_event_sample_rate
,
1083 .maxlen
= sizeof(sysctl_perf_event_sample_rate
),
1085 .proc_handler
= perf_proc_update_handler
,
1089 .procname
= "perf_cpu_time_max_percent",
1090 .data
= &sysctl_perf_cpu_time_max_percent
,
1091 .maxlen
= sizeof(sysctl_perf_cpu_time_max_percent
),
1093 .proc_handler
= perf_cpu_time_max_percent_handler
,
1095 .extra2
= &one_hundred
,
1098 #ifdef CONFIG_KMEMCHECK
1100 .procname
= "kmemcheck",
1101 .data
= &kmemcheck_enabled
,
1102 .maxlen
= sizeof(int),
1104 .proc_handler
= proc_dointvec
,
1108 .procname
= "panic_on_warn",
1109 .data
= &panic_on_warn
,
1110 .maxlen
= sizeof(int),
1112 .proc_handler
= proc_dointvec_minmax
,
1119 static struct ctl_table vm_table
[] = {
1121 .procname
= "overcommit_memory",
1122 .data
= &sysctl_overcommit_memory
,
1123 .maxlen
= sizeof(sysctl_overcommit_memory
),
1125 .proc_handler
= proc_dointvec_minmax
,
1130 .procname
= "panic_on_oom",
1131 .data
= &sysctl_panic_on_oom
,
1132 .maxlen
= sizeof(sysctl_panic_on_oom
),
1134 .proc_handler
= proc_dointvec_minmax
,
1139 .procname
= "oom_kill_allocating_task",
1140 .data
= &sysctl_oom_kill_allocating_task
,
1141 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
1143 .proc_handler
= proc_dointvec
,
1146 .procname
= "oom_dump_tasks",
1147 .data
= &sysctl_oom_dump_tasks
,
1148 .maxlen
= sizeof(sysctl_oom_dump_tasks
),
1150 .proc_handler
= proc_dointvec
,
1153 .procname
= "overcommit_ratio",
1154 .data
= &sysctl_overcommit_ratio
,
1155 .maxlen
= sizeof(sysctl_overcommit_ratio
),
1157 .proc_handler
= overcommit_ratio_handler
,
1160 .procname
= "overcommit_kbytes",
1161 .data
= &sysctl_overcommit_kbytes
,
1162 .maxlen
= sizeof(sysctl_overcommit_kbytes
),
1164 .proc_handler
= overcommit_kbytes_handler
,
1167 .procname
= "page-cluster",
1168 .data
= &page_cluster
,
1169 .maxlen
= sizeof(int),
1171 .proc_handler
= proc_dointvec_minmax
,
1175 .procname
= "dirty_background_ratio",
1176 .data
= &dirty_background_ratio
,
1177 .maxlen
= sizeof(dirty_background_ratio
),
1179 .proc_handler
= dirty_background_ratio_handler
,
1181 .extra2
= &one_hundred
,
1184 .procname
= "dirty_background_bytes",
1185 .data
= &dirty_background_bytes
,
1186 .maxlen
= sizeof(dirty_background_bytes
),
1188 .proc_handler
= dirty_background_bytes_handler
,
1192 .procname
= "dirty_ratio",
1193 .data
= &vm_dirty_ratio
,
1194 .maxlen
= sizeof(vm_dirty_ratio
),
1196 .proc_handler
= dirty_ratio_handler
,
1198 .extra2
= &one_hundred
,
1201 .procname
= "dirty_bytes",
1202 .data
= &vm_dirty_bytes
,
1203 .maxlen
= sizeof(vm_dirty_bytes
),
1205 .proc_handler
= dirty_bytes_handler
,
1206 .extra1
= &dirty_bytes_min
,
1209 .procname
= "dirty_writeback_centisecs",
1210 .data
= &dirty_writeback_interval
,
1211 .maxlen
= sizeof(dirty_writeback_interval
),
1213 .proc_handler
= dirty_writeback_centisecs_handler
,
1216 .procname
= "dirty_expire_centisecs",
1217 .data
= &dirty_expire_interval
,
1218 .maxlen
= sizeof(dirty_expire_interval
),
1220 .proc_handler
= proc_dointvec_minmax
,
1224 .procname
= "nr_pdflush_threads",
1225 .mode
= 0444 /* read-only */,
1226 .proc_handler
= pdflush_proc_obsolete
,
1229 .procname
= "swappiness",
1230 .data
= &vm_swappiness
,
1231 .maxlen
= sizeof(vm_swappiness
),
1233 .proc_handler
= proc_dointvec_minmax
,
1235 .extra2
= &one_hundred
,
1237 #ifdef CONFIG_HUGETLB_PAGE
1239 .procname
= "nr_hugepages",
1241 .maxlen
= sizeof(unsigned long),
1243 .proc_handler
= hugetlb_sysctl_handler
,
1248 .procname
= "nr_hugepages_mempolicy",
1250 .maxlen
= sizeof(unsigned long),
1252 .proc_handler
= &hugetlb_mempolicy_sysctl_handler
,
1257 .procname
= "hugetlb_shm_group",
1258 .data
= &sysctl_hugetlb_shm_group
,
1259 .maxlen
= sizeof(gid_t
),
1261 .proc_handler
= proc_dointvec
,
1264 .procname
= "hugepages_treat_as_movable",
1265 .data
= &hugepages_treat_as_movable
,
1266 .maxlen
= sizeof(int),
1268 .proc_handler
= proc_dointvec
,
1271 .procname
= "nr_overcommit_hugepages",
1273 .maxlen
= sizeof(unsigned long),
1275 .proc_handler
= hugetlb_overcommit_handler
,
1280 .procname
= "lowmem_reserve_ratio",
1281 .data
= &sysctl_lowmem_reserve_ratio
,
1282 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
1284 .proc_handler
= lowmem_reserve_ratio_sysctl_handler
,
1287 .procname
= "drop_caches",
1288 .data
= &sysctl_drop_caches
,
1289 .maxlen
= sizeof(int),
1291 .proc_handler
= drop_caches_sysctl_handler
,
1295 #ifdef CONFIG_COMPACTION
1297 .procname
= "compact_memory",
1298 .data
= &sysctl_compact_memory
,
1299 .maxlen
= sizeof(int),
1301 .proc_handler
= sysctl_compaction_handler
,
1304 .procname
= "extfrag_threshold",
1305 .data
= &sysctl_extfrag_threshold
,
1306 .maxlen
= sizeof(int),
1308 .proc_handler
= sysctl_extfrag_handler
,
1309 .extra1
= &min_extfrag_threshold
,
1310 .extra2
= &max_extfrag_threshold
,
1313 #endif /* CONFIG_COMPACTION */
1315 .procname
= "min_free_kbytes",
1316 .data
= &min_free_kbytes
,
1317 .maxlen
= sizeof(min_free_kbytes
),
1319 .proc_handler
= min_free_kbytes_sysctl_handler
,
1323 .procname
= "percpu_pagelist_fraction",
1324 .data
= &percpu_pagelist_fraction
,
1325 .maxlen
= sizeof(percpu_pagelist_fraction
),
1327 .proc_handler
= percpu_pagelist_fraction_sysctl_handler
,
1332 .procname
= "max_map_count",
1333 .data
= &sysctl_max_map_count
,
1334 .maxlen
= sizeof(sysctl_max_map_count
),
1336 .proc_handler
= proc_dointvec_minmax
,
1341 .procname
= "nr_trim_pages",
1342 .data
= &sysctl_nr_trim_pages
,
1343 .maxlen
= sizeof(sysctl_nr_trim_pages
),
1345 .proc_handler
= proc_dointvec_minmax
,
1350 .procname
= "laptop_mode",
1351 .data
= &laptop_mode
,
1352 .maxlen
= sizeof(laptop_mode
),
1354 .proc_handler
= proc_dointvec_jiffies
,
1357 .procname
= "block_dump",
1358 .data
= &block_dump
,
1359 .maxlen
= sizeof(block_dump
),
1361 .proc_handler
= proc_dointvec
,
1365 .procname
= "vfs_cache_pressure",
1366 .data
= &sysctl_vfs_cache_pressure
,
1367 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
1369 .proc_handler
= proc_dointvec
,
1372 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1374 .procname
= "legacy_va_layout",
1375 .data
= &sysctl_legacy_va_layout
,
1376 .maxlen
= sizeof(sysctl_legacy_va_layout
),
1378 .proc_handler
= proc_dointvec
,
1384 .procname
= "zone_reclaim_mode",
1385 .data
= &zone_reclaim_mode
,
1386 .maxlen
= sizeof(zone_reclaim_mode
),
1388 .proc_handler
= proc_dointvec
,
1392 .procname
= "min_unmapped_ratio",
1393 .data
= &sysctl_min_unmapped_ratio
,
1394 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1396 .proc_handler
= sysctl_min_unmapped_ratio_sysctl_handler
,
1398 .extra2
= &one_hundred
,
1401 .procname
= "min_slab_ratio",
1402 .data
= &sysctl_min_slab_ratio
,
1403 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1405 .proc_handler
= sysctl_min_slab_ratio_sysctl_handler
,
1407 .extra2
= &one_hundred
,
1412 .procname
= "stat_interval",
1413 .data
= &sysctl_stat_interval
,
1414 .maxlen
= sizeof(sysctl_stat_interval
),
1416 .proc_handler
= proc_dointvec_jiffies
,
1421 .procname
= "mmap_min_addr",
1422 .data
= &dac_mmap_min_addr
,
1423 .maxlen
= sizeof(unsigned long),
1425 .proc_handler
= mmap_min_addr_handler
,
1430 .procname
= "numa_zonelist_order",
1431 .data
= &numa_zonelist_order
,
1432 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1434 .proc_handler
= numa_zonelist_order_handler
,
1437 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1438 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1440 .procname
= "vdso_enabled",
1441 #ifdef CONFIG_X86_32
1442 .data
= &vdso32_enabled
,
1443 .maxlen
= sizeof(vdso32_enabled
),
1445 .data
= &vdso_enabled
,
1446 .maxlen
= sizeof(vdso_enabled
),
1449 .proc_handler
= proc_dointvec
,
1453 #ifdef CONFIG_HIGHMEM
1455 .procname
= "highmem_is_dirtyable",
1456 .data
= &vm_highmem_is_dirtyable
,
1457 .maxlen
= sizeof(vm_highmem_is_dirtyable
),
1459 .proc_handler
= proc_dointvec_minmax
,
1464 #ifdef CONFIG_MEMORY_FAILURE
1466 .procname
= "memory_failure_early_kill",
1467 .data
= &sysctl_memory_failure_early_kill
,
1468 .maxlen
= sizeof(sysctl_memory_failure_early_kill
),
1470 .proc_handler
= proc_dointvec_minmax
,
1475 .procname
= "memory_failure_recovery",
1476 .data
= &sysctl_memory_failure_recovery
,
1477 .maxlen
= sizeof(sysctl_memory_failure_recovery
),
1479 .proc_handler
= proc_dointvec_minmax
,
1485 .procname
= "user_reserve_kbytes",
1486 .data
= &sysctl_user_reserve_kbytes
,
1487 .maxlen
= sizeof(sysctl_user_reserve_kbytes
),
1489 .proc_handler
= proc_doulongvec_minmax
,
1492 .procname
= "admin_reserve_kbytes",
1493 .data
= &sysctl_admin_reserve_kbytes
,
1494 .maxlen
= sizeof(sysctl_admin_reserve_kbytes
),
1496 .proc_handler
= proc_doulongvec_minmax
,
1501 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1502 static struct ctl_table binfmt_misc_table
[] = {
1507 static struct ctl_table fs_table
[] = {
1509 .procname
= "inode-nr",
1510 .data
= &inodes_stat
,
1511 .maxlen
= 2*sizeof(long),
1513 .proc_handler
= proc_nr_inodes
,
1516 .procname
= "inode-state",
1517 .data
= &inodes_stat
,
1518 .maxlen
= 7*sizeof(long),
1520 .proc_handler
= proc_nr_inodes
,
1523 .procname
= "file-nr",
1524 .data
= &files_stat
,
1525 .maxlen
= sizeof(files_stat
),
1527 .proc_handler
= proc_nr_files
,
1530 .procname
= "file-max",
1531 .data
= &files_stat
.max_files
,
1532 .maxlen
= sizeof(files_stat
.max_files
),
1534 .proc_handler
= proc_doulongvec_minmax
,
1537 .procname
= "nr_open",
1538 .data
= &sysctl_nr_open
,
1539 .maxlen
= sizeof(int),
1541 .proc_handler
= proc_dointvec_minmax
,
1542 .extra1
= &sysctl_nr_open_min
,
1543 .extra2
= &sysctl_nr_open_max
,
1546 .procname
= "dentry-state",
1547 .data
= &dentry_stat
,
1548 .maxlen
= 6*sizeof(long),
1550 .proc_handler
= proc_nr_dentry
,
1553 .procname
= "overflowuid",
1554 .data
= &fs_overflowuid
,
1555 .maxlen
= sizeof(int),
1557 .proc_handler
= proc_dointvec_minmax
,
1558 .extra1
= &minolduid
,
1559 .extra2
= &maxolduid
,
1562 .procname
= "overflowgid",
1563 .data
= &fs_overflowgid
,
1564 .maxlen
= sizeof(int),
1566 .proc_handler
= proc_dointvec_minmax
,
1567 .extra1
= &minolduid
,
1568 .extra2
= &maxolduid
,
1570 #ifdef CONFIG_FILE_LOCKING
1572 .procname
= "leases-enable",
1573 .data
= &leases_enable
,
1574 .maxlen
= sizeof(int),
1576 .proc_handler
= proc_dointvec
,
1579 #ifdef CONFIG_DNOTIFY
1581 .procname
= "dir-notify-enable",
1582 .data
= &dir_notify_enable
,
1583 .maxlen
= sizeof(int),
1585 .proc_handler
= proc_dointvec
,
1589 #ifdef CONFIG_FILE_LOCKING
1591 .procname
= "lease-break-time",
1592 .data
= &lease_break_time
,
1593 .maxlen
= sizeof(int),
1595 .proc_handler
= proc_dointvec
,
1600 .procname
= "aio-nr",
1602 .maxlen
= sizeof(aio_nr
),
1604 .proc_handler
= proc_doulongvec_minmax
,
1607 .procname
= "aio-max-nr",
1608 .data
= &aio_max_nr
,
1609 .maxlen
= sizeof(aio_max_nr
),
1611 .proc_handler
= proc_doulongvec_minmax
,
1613 #endif /* CONFIG_AIO */
1614 #ifdef CONFIG_INOTIFY_USER
1616 .procname
= "inotify",
1618 .child
= inotify_table
,
1623 .procname
= "epoll",
1625 .child
= epoll_table
,
1630 .procname
= "protected_symlinks",
1631 .data
= &sysctl_protected_symlinks
,
1632 .maxlen
= sizeof(int),
1634 .proc_handler
= proc_dointvec_minmax
,
1639 .procname
= "protected_hardlinks",
1640 .data
= &sysctl_protected_hardlinks
,
1641 .maxlen
= sizeof(int),
1643 .proc_handler
= proc_dointvec_minmax
,
1648 .procname
= "suid_dumpable",
1649 .data
= &suid_dumpable
,
1650 .maxlen
= sizeof(int),
1652 .proc_handler
= proc_dointvec_minmax_coredump
,
1656 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1658 .procname
= "binfmt_misc",
1660 .child
= binfmt_misc_table
,
1664 .procname
= "pipe-max-size",
1665 .data
= &pipe_max_size
,
1666 .maxlen
= sizeof(int),
1668 .proc_handler
= &pipe_proc_fn
,
1669 .extra1
= &pipe_min_size
,
1674 static struct ctl_table debug_table
[] = {
1675 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1677 .procname
= "exception-trace",
1678 .data
= &show_unhandled_signals
,
1679 .maxlen
= sizeof(int),
1681 .proc_handler
= proc_dointvec
1684 #if defined(CONFIG_OPTPROBES)
1686 .procname
= "kprobes-optimization",
1687 .data
= &sysctl_kprobes_optimization
,
1688 .maxlen
= sizeof(int),
1690 .proc_handler
= proc_kprobes_optimization_handler
,
1698 static struct ctl_table dev_table
[] = {
1702 int __init
sysctl_init(void)
1704 struct ctl_table_header
*hdr
;
1706 hdr
= register_sysctl_table(sysctl_base_table
);
1707 kmemleak_not_leak(hdr
);
1711 #endif /* CONFIG_SYSCTL */
1717 #ifdef CONFIG_PROC_SYSCTL
1719 static int _proc_do_string(char *data
, int maxlen
, int write
,
1720 char __user
*buffer
,
1721 size_t *lenp
, loff_t
*ppos
)
1727 if (!data
|| !maxlen
|| !*lenp
) {
1733 if (sysctl_writes_strict
== SYSCTL_WRITES_STRICT
) {
1734 /* Only continue writes not past the end of buffer. */
1736 if (len
> maxlen
- 1)
1743 /* Start writing from beginning of buffer. */
1749 while ((p
- buffer
) < *lenp
&& len
< maxlen
- 1) {
1750 if (get_user(c
, p
++))
1752 if (c
== 0 || c
== '\n')
1773 if (copy_to_user(buffer
, data
, len
))
1776 if (put_user('\n', buffer
+ len
))
1786 static void warn_sysctl_write(struct ctl_table
*table
)
1788 pr_warn_once("%s wrote to %s when file position was not 0!\n"
1789 "This will not be supported in the future. To silence this\n"
1790 "warning, set kernel.sysctl_writes_strict = -1\n",
1791 current
->comm
, table
->procname
);
1795 * proc_dostring - read a string sysctl
1796 * @table: the sysctl table
1797 * @write: %TRUE if this is a write to the sysctl file
1798 * @buffer: the user buffer
1799 * @lenp: the size of the user buffer
1800 * @ppos: file position
1802 * Reads/writes a string from/to the user buffer. If the kernel
1803 * buffer provided is not large enough to hold the string, the
1804 * string is truncated. The copied string is %NULL-terminated.
1805 * If the string is being read by the user process, it is copied
1806 * and a newline '\n' is added. It is truncated if the buffer is
1809 * Returns 0 on success.
1811 int proc_dostring(struct ctl_table
*table
, int write
,
1812 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1814 if (write
&& *ppos
&& sysctl_writes_strict
== SYSCTL_WRITES_WARN
)
1815 warn_sysctl_write(table
);
1817 return _proc_do_string((char *)(table
->data
), table
->maxlen
, write
,
1818 (char __user
*)buffer
, lenp
, ppos
);
1821 static size_t proc_skip_spaces(char **buf
)
1824 char *tmp
= skip_spaces(*buf
);
1830 static void proc_skip_char(char **buf
, size_t *size
, const char v
)
1840 #define TMPBUFLEN 22
1842 * proc_get_long - reads an ASCII formatted integer from a user buffer
1844 * @buf: a kernel buffer
1845 * @size: size of the kernel buffer
1846 * @val: this is where the number will be stored
1847 * @neg: set to %TRUE if number is negative
1848 * @perm_tr: a vector which contains the allowed trailers
1849 * @perm_tr_len: size of the perm_tr vector
1850 * @tr: pointer to store the trailer character
1852 * In case of success %0 is returned and @buf and @size are updated with
1853 * the amount of bytes read. If @tr is non-NULL and a trailing
1854 * character exists (size is non-zero after returning from this
1855 * function), @tr is updated with the trailing character.
1857 static int proc_get_long(char **buf
, size_t *size
,
1858 unsigned long *val
, bool *neg
,
1859 const char *perm_tr
, unsigned perm_tr_len
, char *tr
)
1862 char *p
, tmp
[TMPBUFLEN
];
1868 if (len
> TMPBUFLEN
- 1)
1869 len
= TMPBUFLEN
- 1;
1871 memcpy(tmp
, *buf
, len
);
1875 if (*p
== '-' && *size
> 1) {
1883 *val
= simple_strtoul(p
, &p
, 0);
1887 /* We don't know if the next char is whitespace thus we may accept
1888 * invalid integers (e.g. 1234...a) or two integers instead of one
1889 * (e.g. 123...1). So lets not allow such large numbers. */
1890 if (len
== TMPBUFLEN
- 1)
1893 if (len
< *size
&& perm_tr_len
&& !memchr(perm_tr
, *p
, perm_tr_len
))
1896 if (tr
&& (len
< *size
))
1906 * proc_put_long - converts an integer to a decimal ASCII formatted string
1908 * @buf: the user buffer
1909 * @size: the size of the user buffer
1910 * @val: the integer to be converted
1911 * @neg: sign of the number, %TRUE for negative
1913 * In case of success %0 is returned and @buf and @size are updated with
1914 * the amount of bytes written.
1916 static int proc_put_long(void __user
**buf
, size_t *size
, unsigned long val
,
1920 char tmp
[TMPBUFLEN
], *p
= tmp
;
1922 sprintf(p
, "%s%lu", neg
? "-" : "", val
);
1926 if (copy_to_user(*buf
, tmp
, len
))
1934 static int proc_put_char(void __user
**buf
, size_t *size
, char c
)
1937 char __user
**buffer
= (char __user
**)buf
;
1938 if (put_user(c
, *buffer
))
1940 (*size
)--, (*buffer
)++;
1946 static int do_proc_dointvec_conv(bool *negp
, unsigned long *lvalp
,
1948 int write
, void *data
)
1951 *valp
= *negp
? -*lvalp
: *lvalp
;
1956 *lvalp
= (unsigned long)-val
;
1959 *lvalp
= (unsigned long)val
;
1965 static const char proc_wspace_sep
[] = { ' ', '\t', '\n' };
1967 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
1968 int write
, void __user
*buffer
,
1969 size_t *lenp
, loff_t
*ppos
,
1970 int (*conv
)(bool *negp
, unsigned long *lvalp
, int *valp
,
1971 int write
, void *data
),
1974 int *i
, vleft
, first
= 1, err
= 0;
1975 unsigned long page
= 0;
1979 if (!tbl_data
|| !table
->maxlen
|| !*lenp
|| (*ppos
&& !write
)) {
1984 i
= (int *) tbl_data
;
1985 vleft
= table
->maxlen
/ sizeof(*i
);
1989 conv
= do_proc_dointvec_conv
;
1993 switch (sysctl_writes_strict
) {
1994 case SYSCTL_WRITES_STRICT
:
1996 case SYSCTL_WRITES_WARN
:
1997 warn_sysctl_write(table
);
2004 if (left
> PAGE_SIZE
- 1)
2005 left
= PAGE_SIZE
- 1;
2006 page
= __get_free_page(GFP_TEMPORARY
);
2007 kbuf
= (char *) page
;
2010 if (copy_from_user(kbuf
, buffer
, left
)) {
2017 for (; left
&& vleft
--; i
++, first
=0) {
2022 left
-= proc_skip_spaces(&kbuf
);
2026 err
= proc_get_long(&kbuf
, &left
, &lval
, &neg
,
2028 sizeof(proc_wspace_sep
), NULL
);
2031 if (conv(&neg
, &lval
, i
, 1, data
)) {
2036 if (conv(&neg
, &lval
, i
, 0, data
)) {
2041 err
= proc_put_char(&buffer
, &left
, '\t');
2044 err
= proc_put_long(&buffer
, &left
, lval
, neg
);
2050 if (!write
&& !first
&& left
&& !err
)
2051 err
= proc_put_char(&buffer
, &left
, '\n');
2052 if (write
&& !err
&& left
)
2053 left
-= proc_skip_spaces(&kbuf
);
2058 return err
? : -EINVAL
;
2066 static int do_proc_dointvec(struct ctl_table
*table
, int write
,
2067 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
2068 int (*conv
)(bool *negp
, unsigned long *lvalp
, int *valp
,
2069 int write
, void *data
),
2072 return __do_proc_dointvec(table
->data
, table
, write
,
2073 buffer
, lenp
, ppos
, conv
, data
);
2077 * proc_dointvec - read a vector of integers
2078 * @table: the sysctl table
2079 * @write: %TRUE if this is a write to the sysctl file
2080 * @buffer: the user buffer
2081 * @lenp: the size of the user buffer
2082 * @ppos: file position
2084 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2085 * values from/to the user buffer, treated as an ASCII string.
2087 * Returns 0 on success.
2089 int proc_dointvec(struct ctl_table
*table
, int write
,
2090 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2092 return do_proc_dointvec(table
,write
,buffer
,lenp
,ppos
,
2097 * Taint values can only be increased
2098 * This means we can safely use a temporary.
2100 static int proc_taint(struct ctl_table
*table
, int write
,
2101 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2104 unsigned long tmptaint
= get_taint();
2107 if (write
&& !capable(CAP_SYS_ADMIN
))
2112 err
= proc_doulongvec_minmax(&t
, write
, buffer
, lenp
, ppos
);
2118 * Poor man's atomic or. Not worth adding a primitive
2119 * to everyone's atomic.h for this
2122 for (i
= 0; i
< BITS_PER_LONG
&& tmptaint
>> i
; i
++) {
2123 if ((tmptaint
>> i
) & 1)
2124 add_taint(i
, LOCKDEP_STILL_OK
);
2131 #ifdef CONFIG_PRINTK
2132 static int proc_dointvec_minmax_sysadmin(struct ctl_table
*table
, int write
,
2133 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2135 if (write
&& !capable(CAP_SYS_ADMIN
))
2138 return proc_dointvec_minmax(table
, write
, buffer
, lenp
, ppos
);
2142 struct do_proc_dointvec_minmax_conv_param
{
2147 static int do_proc_dointvec_minmax_conv(bool *negp
, unsigned long *lvalp
,
2149 int write
, void *data
)
2151 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
2153 int val
= *negp
? -*lvalp
: *lvalp
;
2154 if ((param
->min
&& *param
->min
> val
) ||
2155 (param
->max
&& *param
->max
< val
))
2162 *lvalp
= (unsigned long)-val
;
2165 *lvalp
= (unsigned long)val
;
2172 * proc_dointvec_minmax - read a vector of integers with min/max values
2173 * @table: the sysctl table
2174 * @write: %TRUE if this is a write to the sysctl file
2175 * @buffer: the user buffer
2176 * @lenp: the size of the user buffer
2177 * @ppos: file position
2179 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2180 * values from/to the user buffer, treated as an ASCII string.
2182 * This routine will ensure the values are within the range specified by
2183 * table->extra1 (min) and table->extra2 (max).
2185 * Returns 0 on success.
2187 int proc_dointvec_minmax(struct ctl_table
*table
, int write
,
2188 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2190 struct do_proc_dointvec_minmax_conv_param param
= {
2191 .min
= (int *) table
->extra1
,
2192 .max
= (int *) table
->extra2
,
2194 return do_proc_dointvec(table
, write
, buffer
, lenp
, ppos
,
2195 do_proc_dointvec_minmax_conv
, ¶m
);
2198 static void validate_coredump_safety(void)
2200 #ifdef CONFIG_COREDUMP
2201 if (suid_dumpable
== SUID_DUMP_ROOT
&&
2202 core_pattern
[0] != '/' && core_pattern
[0] != '|') {
2203 printk(KERN_WARNING
"Unsafe core_pattern used with "\
2204 "suid_dumpable=2. Pipe handler or fully qualified "\
2205 "core dump path required.\n");
2210 static int proc_dointvec_minmax_coredump(struct ctl_table
*table
, int write
,
2211 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2213 int error
= proc_dointvec_minmax(table
, write
, buffer
, lenp
, ppos
);
2215 validate_coredump_safety();
2219 #ifdef CONFIG_COREDUMP
2220 static int proc_dostring_coredump(struct ctl_table
*table
, int write
,
2221 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2223 int error
= proc_dostring(table
, write
, buffer
, lenp
, ppos
);
2225 validate_coredump_safety();
2230 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
2231 void __user
*buffer
,
2232 size_t *lenp
, loff_t
*ppos
,
2233 unsigned long convmul
,
2234 unsigned long convdiv
)
2236 unsigned long *i
, *min
, *max
;
2237 int vleft
, first
= 1, err
= 0;
2238 unsigned long page
= 0;
2242 if (!data
|| !table
->maxlen
|| !*lenp
|| (*ppos
&& !write
)) {
2247 i
= (unsigned long *) data
;
2248 min
= (unsigned long *) table
->extra1
;
2249 max
= (unsigned long *) table
->extra2
;
2250 vleft
= table
->maxlen
/ sizeof(unsigned long);
2255 switch (sysctl_writes_strict
) {
2256 case SYSCTL_WRITES_STRICT
:
2258 case SYSCTL_WRITES_WARN
:
2259 warn_sysctl_write(table
);
2266 if (left
> PAGE_SIZE
- 1)
2267 left
= PAGE_SIZE
- 1;
2268 page
= __get_free_page(GFP_TEMPORARY
);
2269 kbuf
= (char *) page
;
2272 if (copy_from_user(kbuf
, buffer
, left
)) {
2279 for (; left
&& vleft
--; i
++, first
= 0) {
2285 left
-= proc_skip_spaces(&kbuf
);
2287 err
= proc_get_long(&kbuf
, &left
, &val
, &neg
,
2289 sizeof(proc_wspace_sep
), NULL
);
2294 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2298 val
= convdiv
* (*i
) / convmul
;
2300 err
= proc_put_char(&buffer
, &left
, '\t');
2304 err
= proc_put_long(&buffer
, &left
, val
, false);
2310 if (!write
&& !first
&& left
&& !err
)
2311 err
= proc_put_char(&buffer
, &left
, '\n');
2313 left
-= proc_skip_spaces(&kbuf
);
2318 return err
? : -EINVAL
;
2326 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2327 void __user
*buffer
,
2328 size_t *lenp
, loff_t
*ppos
,
2329 unsigned long convmul
,
2330 unsigned long convdiv
)
2332 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2333 buffer
, lenp
, ppos
, convmul
, convdiv
);
2337 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2338 * @table: the sysctl table
2339 * @write: %TRUE if this is a write to the sysctl file
2340 * @buffer: the user buffer
2341 * @lenp: the size of the user buffer
2342 * @ppos: file position
2344 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2345 * values from/to the user buffer, treated as an ASCII string.
2347 * This routine will ensure the values are within the range specified by
2348 * table->extra1 (min) and table->extra2 (max).
2350 * Returns 0 on success.
2352 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2353 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2355 return do_proc_doulongvec_minmax(table
, write
, buffer
, lenp
, ppos
, 1l, 1l);
2359 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2360 * @table: the sysctl table
2361 * @write: %TRUE if this is a write to the sysctl file
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 long) unsigned long
2367 * values from/to the user buffer, treated as an ASCII string. The values
2368 * are treated as milliseconds, and converted to jiffies when they are stored.
2370 * This routine will ensure the values are within the range specified by
2371 * table->extra1 (min) and table->extra2 (max).
2373 * Returns 0 on success.
2375 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2376 void __user
*buffer
,
2377 size_t *lenp
, loff_t
*ppos
)
2379 return do_proc_doulongvec_minmax(table
, write
, buffer
,
2380 lenp
, ppos
, HZ
, 1000l);
2384 static int do_proc_dointvec_jiffies_conv(bool *negp
, unsigned long *lvalp
,
2386 int write
, void *data
)
2389 if (*lvalp
> LONG_MAX
/ HZ
)
2391 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2397 lval
= (unsigned long)-val
;
2400 lval
= (unsigned long)val
;
2407 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp
, unsigned long *lvalp
,
2409 int write
, void *data
)
2412 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2414 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2420 lval
= (unsigned long)-val
;
2423 lval
= (unsigned long)val
;
2425 *lvalp
= jiffies_to_clock_t(lval
);
2430 static int do_proc_dointvec_ms_jiffies_conv(bool *negp
, unsigned long *lvalp
,
2432 int write
, void *data
)
2435 unsigned long jif
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2445 lval
= (unsigned long)-val
;
2448 lval
= (unsigned long)val
;
2450 *lvalp
= jiffies_to_msecs(lval
);
2456 * proc_dointvec_jiffies - read a vector of integers as seconds
2457 * @table: the sysctl table
2458 * @write: %TRUE if this is a write to the sysctl file
2459 * @buffer: the user buffer
2460 * @lenp: the size of the user buffer
2461 * @ppos: file position
2463 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2464 * values from/to the user buffer, treated as an ASCII string.
2465 * The values read are assumed to be in seconds, and are converted into
2468 * Returns 0 on success.
2470 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
,
2471 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2473 return do_proc_dointvec(table
,write
,buffer
,lenp
,ppos
,
2474 do_proc_dointvec_jiffies_conv
,NULL
);
2478 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2479 * @table: the sysctl table
2480 * @write: %TRUE if this is a write to the sysctl file
2481 * @buffer: the user buffer
2482 * @lenp: the size of the user buffer
2483 * @ppos: pointer to the file position
2485 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2486 * values from/to the user buffer, treated as an ASCII string.
2487 * The values read are assumed to be in 1/USER_HZ seconds, and
2488 * are converted into jiffies.
2490 * Returns 0 on success.
2492 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
,
2493 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2495 return do_proc_dointvec(table
,write
,buffer
,lenp
,ppos
,
2496 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2500 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2501 * @table: the sysctl table
2502 * @write: %TRUE if this is a write to the sysctl file
2503 * @buffer: the user buffer
2504 * @lenp: the size of the user buffer
2505 * @ppos: file position
2506 * @ppos: the current position in the file
2508 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2509 * values from/to the user buffer, treated as an ASCII string.
2510 * The values read are assumed to be in 1/1000 seconds, and
2511 * are converted into jiffies.
2513 * Returns 0 on success.
2515 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
,
2516 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2518 return do_proc_dointvec(table
, write
, buffer
, lenp
, ppos
,
2519 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2522 static int proc_do_cad_pid(struct ctl_table
*table
, int write
,
2523 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2525 struct pid
*new_pid
;
2529 tmp
= pid_vnr(cad_pid
);
2531 r
= __do_proc_dointvec(&tmp
, table
, write
, buffer
,
2532 lenp
, ppos
, NULL
, NULL
);
2536 new_pid
= find_get_pid(tmp
);
2540 put_pid(xchg(&cad_pid
, new_pid
));
2545 * proc_do_large_bitmap - read/write from/to a large bitmap
2546 * @table: the sysctl table
2547 * @write: %TRUE if this is a write to the sysctl file
2548 * @buffer: the user buffer
2549 * @lenp: the size of the user buffer
2550 * @ppos: file position
2552 * The bitmap is stored at table->data and the bitmap length (in bits)
2555 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2556 * large bitmaps may be represented in a compact manner. Writing into
2557 * the file will clear the bitmap then update it with the given input.
2559 * Returns 0 on success.
2561 int proc_do_large_bitmap(struct ctl_table
*table
, int write
,
2562 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2566 size_t left
= *lenp
;
2567 unsigned long bitmap_len
= table
->maxlen
;
2568 unsigned long *bitmap
= *(unsigned long **) table
->data
;
2569 unsigned long *tmp_bitmap
= NULL
;
2570 char tr_a
[] = { '-', ',', '\n' }, tr_b
[] = { ',', '\n', 0 }, c
;
2572 if (!bitmap
|| !bitmap_len
|| !left
|| (*ppos
&& !write
)) {
2578 unsigned long page
= 0;
2581 if (left
> PAGE_SIZE
- 1)
2582 left
= PAGE_SIZE
- 1;
2584 page
= __get_free_page(GFP_TEMPORARY
);
2585 kbuf
= (char *) page
;
2588 if (copy_from_user(kbuf
, buffer
, left
)) {
2594 tmp_bitmap
= kzalloc(BITS_TO_LONGS(bitmap_len
) * sizeof(unsigned long),
2600 proc_skip_char(&kbuf
, &left
, '\n');
2601 while (!err
&& left
) {
2602 unsigned long val_a
, val_b
;
2605 err
= proc_get_long(&kbuf
, &left
, &val_a
, &neg
, tr_a
,
2609 if (val_a
>= bitmap_len
|| neg
) {
2621 err
= proc_get_long(&kbuf
, &left
, &val_b
,
2622 &neg
, tr_b
, sizeof(tr_b
),
2626 if (val_b
>= bitmap_len
|| neg
||
2637 bitmap_set(tmp_bitmap
, val_a
, val_b
- val_a
+ 1);
2639 proc_skip_char(&kbuf
, &left
, '\n');
2643 unsigned long bit_a
, bit_b
= 0;
2646 bit_a
= find_next_bit(bitmap
, bitmap_len
, bit_b
);
2647 if (bit_a
>= bitmap_len
)
2649 bit_b
= find_next_zero_bit(bitmap
, bitmap_len
,
2653 err
= proc_put_char(&buffer
, &left
, ',');
2657 err
= proc_put_long(&buffer
, &left
, bit_a
, false);
2660 if (bit_a
!= bit_b
) {
2661 err
= proc_put_char(&buffer
, &left
, '-');
2664 err
= proc_put_long(&buffer
, &left
, bit_b
, false);
2672 err
= proc_put_char(&buffer
, &left
, '\n');
2678 bitmap_or(bitmap
, bitmap
, tmp_bitmap
, bitmap_len
);
2680 bitmap_copy(bitmap
, tmp_bitmap
, bitmap_len
);
2692 #else /* CONFIG_PROC_SYSCTL */
2694 int proc_dostring(struct ctl_table
*table
, int write
,
2695 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2700 int proc_dointvec(struct ctl_table
*table
, int write
,
2701 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2706 int proc_dointvec_minmax(struct ctl_table
*table
, int write
,
2707 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2712 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
,
2713 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2718 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
,
2719 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2724 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
,
2725 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2730 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2731 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2736 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2737 void __user
*buffer
,
2738 size_t *lenp
, loff_t
*ppos
)
2744 #endif /* CONFIG_PROC_SYSCTL */
2747 * No sense putting this after each symbol definition, twice,
2748 * exception granted :-)
2750 EXPORT_SYMBOL(proc_dointvec
);
2751 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2752 EXPORT_SYMBOL(proc_dointvec_minmax
);
2753 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2754 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2755 EXPORT_SYMBOL(proc_dostring
);
2756 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2757 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);