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
,
1110 static struct ctl_table vm_table
[] = {
1112 .procname
= "overcommit_memory",
1113 .data
= &sysctl_overcommit_memory
,
1114 .maxlen
= sizeof(sysctl_overcommit_memory
),
1116 .proc_handler
= proc_dointvec_minmax
,
1121 .procname
= "panic_on_oom",
1122 .data
= &sysctl_panic_on_oom
,
1123 .maxlen
= sizeof(sysctl_panic_on_oom
),
1125 .proc_handler
= proc_dointvec_minmax
,
1130 .procname
= "oom_kill_allocating_task",
1131 .data
= &sysctl_oom_kill_allocating_task
,
1132 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
1134 .proc_handler
= proc_dointvec
,
1137 .procname
= "oom_dump_tasks",
1138 .data
= &sysctl_oom_dump_tasks
,
1139 .maxlen
= sizeof(sysctl_oom_dump_tasks
),
1141 .proc_handler
= proc_dointvec
,
1144 .procname
= "overcommit_ratio",
1145 .data
= &sysctl_overcommit_ratio
,
1146 .maxlen
= sizeof(sysctl_overcommit_ratio
),
1148 .proc_handler
= overcommit_ratio_handler
,
1151 .procname
= "overcommit_kbytes",
1152 .data
= &sysctl_overcommit_kbytes
,
1153 .maxlen
= sizeof(sysctl_overcommit_kbytes
),
1155 .proc_handler
= overcommit_kbytes_handler
,
1158 .procname
= "page-cluster",
1159 .data
= &page_cluster
,
1160 .maxlen
= sizeof(int),
1162 .proc_handler
= proc_dointvec_minmax
,
1166 .procname
= "dirty_background_ratio",
1167 .data
= &dirty_background_ratio
,
1168 .maxlen
= sizeof(dirty_background_ratio
),
1170 .proc_handler
= dirty_background_ratio_handler
,
1172 .extra2
= &one_hundred
,
1175 .procname
= "dirty_background_bytes",
1176 .data
= &dirty_background_bytes
,
1177 .maxlen
= sizeof(dirty_background_bytes
),
1179 .proc_handler
= dirty_background_bytes_handler
,
1183 .procname
= "dirty_ratio",
1184 .data
= &vm_dirty_ratio
,
1185 .maxlen
= sizeof(vm_dirty_ratio
),
1187 .proc_handler
= dirty_ratio_handler
,
1189 .extra2
= &one_hundred
,
1192 .procname
= "dirty_bytes",
1193 .data
= &vm_dirty_bytes
,
1194 .maxlen
= sizeof(vm_dirty_bytes
),
1196 .proc_handler
= dirty_bytes_handler
,
1197 .extra1
= &dirty_bytes_min
,
1200 .procname
= "dirty_writeback_centisecs",
1201 .data
= &dirty_writeback_interval
,
1202 .maxlen
= sizeof(dirty_writeback_interval
),
1204 .proc_handler
= dirty_writeback_centisecs_handler
,
1207 .procname
= "dirty_expire_centisecs",
1208 .data
= &dirty_expire_interval
,
1209 .maxlen
= sizeof(dirty_expire_interval
),
1211 .proc_handler
= proc_dointvec_minmax
,
1215 .procname
= "nr_pdflush_threads",
1216 .mode
= 0444 /* read-only */,
1217 .proc_handler
= pdflush_proc_obsolete
,
1220 .procname
= "swappiness",
1221 .data
= &vm_swappiness
,
1222 .maxlen
= sizeof(vm_swappiness
),
1224 .proc_handler
= proc_dointvec_minmax
,
1226 .extra2
= &one_hundred
,
1228 #ifdef CONFIG_HUGETLB_PAGE
1230 .procname
= "nr_hugepages",
1232 .maxlen
= sizeof(unsigned long),
1234 .proc_handler
= hugetlb_sysctl_handler
,
1239 .procname
= "nr_hugepages_mempolicy",
1241 .maxlen
= sizeof(unsigned long),
1243 .proc_handler
= &hugetlb_mempolicy_sysctl_handler
,
1248 .procname
= "hugetlb_shm_group",
1249 .data
= &sysctl_hugetlb_shm_group
,
1250 .maxlen
= sizeof(gid_t
),
1252 .proc_handler
= proc_dointvec
,
1255 .procname
= "hugepages_treat_as_movable",
1256 .data
= &hugepages_treat_as_movable
,
1257 .maxlen
= sizeof(int),
1259 .proc_handler
= proc_dointvec
,
1262 .procname
= "nr_overcommit_hugepages",
1264 .maxlen
= sizeof(unsigned long),
1266 .proc_handler
= hugetlb_overcommit_handler
,
1271 .procname
= "lowmem_reserve_ratio",
1272 .data
= &sysctl_lowmem_reserve_ratio
,
1273 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
1275 .proc_handler
= lowmem_reserve_ratio_sysctl_handler
,
1278 .procname
= "drop_caches",
1279 .data
= &sysctl_drop_caches
,
1280 .maxlen
= sizeof(int),
1282 .proc_handler
= drop_caches_sysctl_handler
,
1286 #ifdef CONFIG_COMPACTION
1288 .procname
= "compact_memory",
1289 .data
= &sysctl_compact_memory
,
1290 .maxlen
= sizeof(int),
1292 .proc_handler
= sysctl_compaction_handler
,
1295 .procname
= "extfrag_threshold",
1296 .data
= &sysctl_extfrag_threshold
,
1297 .maxlen
= sizeof(int),
1299 .proc_handler
= sysctl_extfrag_handler
,
1300 .extra1
= &min_extfrag_threshold
,
1301 .extra2
= &max_extfrag_threshold
,
1304 #endif /* CONFIG_COMPACTION */
1306 .procname
= "min_free_kbytes",
1307 .data
= &min_free_kbytes
,
1308 .maxlen
= sizeof(min_free_kbytes
),
1310 .proc_handler
= min_free_kbytes_sysctl_handler
,
1314 .procname
= "percpu_pagelist_fraction",
1315 .data
= &percpu_pagelist_fraction
,
1316 .maxlen
= sizeof(percpu_pagelist_fraction
),
1318 .proc_handler
= percpu_pagelist_fraction_sysctl_handler
,
1323 .procname
= "max_map_count",
1324 .data
= &sysctl_max_map_count
,
1325 .maxlen
= sizeof(sysctl_max_map_count
),
1327 .proc_handler
= proc_dointvec_minmax
,
1332 .procname
= "nr_trim_pages",
1333 .data
= &sysctl_nr_trim_pages
,
1334 .maxlen
= sizeof(sysctl_nr_trim_pages
),
1336 .proc_handler
= proc_dointvec_minmax
,
1341 .procname
= "laptop_mode",
1342 .data
= &laptop_mode
,
1343 .maxlen
= sizeof(laptop_mode
),
1345 .proc_handler
= proc_dointvec_jiffies
,
1348 .procname
= "block_dump",
1349 .data
= &block_dump
,
1350 .maxlen
= sizeof(block_dump
),
1352 .proc_handler
= proc_dointvec
,
1356 .procname
= "vfs_cache_pressure",
1357 .data
= &sysctl_vfs_cache_pressure
,
1358 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
1360 .proc_handler
= proc_dointvec
,
1363 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1365 .procname
= "legacy_va_layout",
1366 .data
= &sysctl_legacy_va_layout
,
1367 .maxlen
= sizeof(sysctl_legacy_va_layout
),
1369 .proc_handler
= proc_dointvec
,
1375 .procname
= "zone_reclaim_mode",
1376 .data
= &zone_reclaim_mode
,
1377 .maxlen
= sizeof(zone_reclaim_mode
),
1379 .proc_handler
= proc_dointvec
,
1383 .procname
= "min_unmapped_ratio",
1384 .data
= &sysctl_min_unmapped_ratio
,
1385 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1387 .proc_handler
= sysctl_min_unmapped_ratio_sysctl_handler
,
1389 .extra2
= &one_hundred
,
1392 .procname
= "min_slab_ratio",
1393 .data
= &sysctl_min_slab_ratio
,
1394 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1396 .proc_handler
= sysctl_min_slab_ratio_sysctl_handler
,
1398 .extra2
= &one_hundred
,
1403 .procname
= "stat_interval",
1404 .data
= &sysctl_stat_interval
,
1405 .maxlen
= sizeof(sysctl_stat_interval
),
1407 .proc_handler
= proc_dointvec_jiffies
,
1412 .procname
= "mmap_min_addr",
1413 .data
= &dac_mmap_min_addr
,
1414 .maxlen
= sizeof(unsigned long),
1416 .proc_handler
= mmap_min_addr_handler
,
1421 .procname
= "numa_zonelist_order",
1422 .data
= &numa_zonelist_order
,
1423 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1425 .proc_handler
= numa_zonelist_order_handler
,
1428 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1429 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1431 .procname
= "vdso_enabled",
1432 #ifdef CONFIG_X86_32
1433 .data
= &vdso32_enabled
,
1434 .maxlen
= sizeof(vdso32_enabled
),
1436 .data
= &vdso_enabled
,
1437 .maxlen
= sizeof(vdso_enabled
),
1440 .proc_handler
= proc_dointvec
,
1444 #ifdef CONFIG_HIGHMEM
1446 .procname
= "highmem_is_dirtyable",
1447 .data
= &vm_highmem_is_dirtyable
,
1448 .maxlen
= sizeof(vm_highmem_is_dirtyable
),
1450 .proc_handler
= proc_dointvec_minmax
,
1455 #ifdef CONFIG_MEMORY_FAILURE
1457 .procname
= "memory_failure_early_kill",
1458 .data
= &sysctl_memory_failure_early_kill
,
1459 .maxlen
= sizeof(sysctl_memory_failure_early_kill
),
1461 .proc_handler
= proc_dointvec_minmax
,
1466 .procname
= "memory_failure_recovery",
1467 .data
= &sysctl_memory_failure_recovery
,
1468 .maxlen
= sizeof(sysctl_memory_failure_recovery
),
1470 .proc_handler
= proc_dointvec_minmax
,
1476 .procname
= "user_reserve_kbytes",
1477 .data
= &sysctl_user_reserve_kbytes
,
1478 .maxlen
= sizeof(sysctl_user_reserve_kbytes
),
1480 .proc_handler
= proc_doulongvec_minmax
,
1483 .procname
= "admin_reserve_kbytes",
1484 .data
= &sysctl_admin_reserve_kbytes
,
1485 .maxlen
= sizeof(sysctl_admin_reserve_kbytes
),
1487 .proc_handler
= proc_doulongvec_minmax
,
1492 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1493 static struct ctl_table binfmt_misc_table
[] = {
1498 static struct ctl_table fs_table
[] = {
1500 .procname
= "inode-nr",
1501 .data
= &inodes_stat
,
1502 .maxlen
= 2*sizeof(long),
1504 .proc_handler
= proc_nr_inodes
,
1507 .procname
= "inode-state",
1508 .data
= &inodes_stat
,
1509 .maxlen
= 7*sizeof(long),
1511 .proc_handler
= proc_nr_inodes
,
1514 .procname
= "file-nr",
1515 .data
= &files_stat
,
1516 .maxlen
= sizeof(files_stat
),
1518 .proc_handler
= proc_nr_files
,
1521 .procname
= "file-max",
1522 .data
= &files_stat
.max_files
,
1523 .maxlen
= sizeof(files_stat
.max_files
),
1525 .proc_handler
= proc_doulongvec_minmax
,
1528 .procname
= "nr_open",
1529 .data
= &sysctl_nr_open
,
1530 .maxlen
= sizeof(int),
1532 .proc_handler
= proc_dointvec_minmax
,
1533 .extra1
= &sysctl_nr_open_min
,
1534 .extra2
= &sysctl_nr_open_max
,
1537 .procname
= "dentry-state",
1538 .data
= &dentry_stat
,
1539 .maxlen
= 6*sizeof(long),
1541 .proc_handler
= proc_nr_dentry
,
1544 .procname
= "overflowuid",
1545 .data
= &fs_overflowuid
,
1546 .maxlen
= sizeof(int),
1548 .proc_handler
= proc_dointvec_minmax
,
1549 .extra1
= &minolduid
,
1550 .extra2
= &maxolduid
,
1553 .procname
= "overflowgid",
1554 .data
= &fs_overflowgid
,
1555 .maxlen
= sizeof(int),
1557 .proc_handler
= proc_dointvec_minmax
,
1558 .extra1
= &minolduid
,
1559 .extra2
= &maxolduid
,
1561 #ifdef CONFIG_FILE_LOCKING
1563 .procname
= "leases-enable",
1564 .data
= &leases_enable
,
1565 .maxlen
= sizeof(int),
1567 .proc_handler
= proc_dointvec
,
1570 #ifdef CONFIG_DNOTIFY
1572 .procname
= "dir-notify-enable",
1573 .data
= &dir_notify_enable
,
1574 .maxlen
= sizeof(int),
1576 .proc_handler
= proc_dointvec
,
1580 #ifdef CONFIG_FILE_LOCKING
1582 .procname
= "lease-break-time",
1583 .data
= &lease_break_time
,
1584 .maxlen
= sizeof(int),
1586 .proc_handler
= proc_dointvec
,
1591 .procname
= "aio-nr",
1593 .maxlen
= sizeof(aio_nr
),
1595 .proc_handler
= proc_doulongvec_minmax
,
1598 .procname
= "aio-max-nr",
1599 .data
= &aio_max_nr
,
1600 .maxlen
= sizeof(aio_max_nr
),
1602 .proc_handler
= proc_doulongvec_minmax
,
1604 #endif /* CONFIG_AIO */
1605 #ifdef CONFIG_INOTIFY_USER
1607 .procname
= "inotify",
1609 .child
= inotify_table
,
1614 .procname
= "epoll",
1616 .child
= epoll_table
,
1621 .procname
= "protected_symlinks",
1622 .data
= &sysctl_protected_symlinks
,
1623 .maxlen
= sizeof(int),
1625 .proc_handler
= proc_dointvec_minmax
,
1630 .procname
= "protected_hardlinks",
1631 .data
= &sysctl_protected_hardlinks
,
1632 .maxlen
= sizeof(int),
1634 .proc_handler
= proc_dointvec_minmax
,
1639 .procname
= "suid_dumpable",
1640 .data
= &suid_dumpable
,
1641 .maxlen
= sizeof(int),
1643 .proc_handler
= proc_dointvec_minmax_coredump
,
1647 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1649 .procname
= "binfmt_misc",
1651 .child
= binfmt_misc_table
,
1655 .procname
= "pipe-max-size",
1656 .data
= &pipe_max_size
,
1657 .maxlen
= sizeof(int),
1659 .proc_handler
= &pipe_proc_fn
,
1660 .extra1
= &pipe_min_size
,
1665 static struct ctl_table debug_table
[] = {
1666 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1668 .procname
= "exception-trace",
1669 .data
= &show_unhandled_signals
,
1670 .maxlen
= sizeof(int),
1672 .proc_handler
= proc_dointvec
1675 #if defined(CONFIG_OPTPROBES)
1677 .procname
= "kprobes-optimization",
1678 .data
= &sysctl_kprobes_optimization
,
1679 .maxlen
= sizeof(int),
1681 .proc_handler
= proc_kprobes_optimization_handler
,
1689 static struct ctl_table dev_table
[] = {
1693 int __init
sysctl_init(void)
1695 struct ctl_table_header
*hdr
;
1697 hdr
= register_sysctl_table(sysctl_base_table
);
1698 kmemleak_not_leak(hdr
);
1702 #endif /* CONFIG_SYSCTL */
1708 #ifdef CONFIG_PROC_SYSCTL
1710 static int _proc_do_string(char *data
, int maxlen
, int write
,
1711 char __user
*buffer
,
1712 size_t *lenp
, loff_t
*ppos
)
1718 if (!data
|| !maxlen
|| !*lenp
) {
1724 if (sysctl_writes_strict
== SYSCTL_WRITES_STRICT
) {
1725 /* Only continue writes not past the end of buffer. */
1727 if (len
> maxlen
- 1)
1734 /* Start writing from beginning of buffer. */
1740 while ((p
- buffer
) < *lenp
&& len
< maxlen
- 1) {
1741 if (get_user(c
, p
++))
1743 if (c
== 0 || c
== '\n')
1764 if (copy_to_user(buffer
, data
, len
))
1767 if (put_user('\n', buffer
+ len
))
1777 static void warn_sysctl_write(struct ctl_table
*table
)
1779 pr_warn_once("%s wrote to %s when file position was not 0!\n"
1780 "This will not be supported in the future. To silence this\n"
1781 "warning, set kernel.sysctl_writes_strict = -1\n",
1782 current
->comm
, table
->procname
);
1786 * proc_dostring - read a string sysctl
1787 * @table: the sysctl table
1788 * @write: %TRUE if this is a write to the sysctl file
1789 * @buffer: the user buffer
1790 * @lenp: the size of the user buffer
1791 * @ppos: file position
1793 * Reads/writes a string from/to the user buffer. If the kernel
1794 * buffer provided is not large enough to hold the string, the
1795 * string is truncated. The copied string is %NULL-terminated.
1796 * If the string is being read by the user process, it is copied
1797 * and a newline '\n' is added. It is truncated if the buffer is
1800 * Returns 0 on success.
1802 int proc_dostring(struct ctl_table
*table
, int write
,
1803 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1805 if (write
&& *ppos
&& sysctl_writes_strict
== SYSCTL_WRITES_WARN
)
1806 warn_sysctl_write(table
);
1808 return _proc_do_string((char *)(table
->data
), table
->maxlen
, write
,
1809 (char __user
*)buffer
, lenp
, ppos
);
1812 static size_t proc_skip_spaces(char **buf
)
1815 char *tmp
= skip_spaces(*buf
);
1821 static void proc_skip_char(char **buf
, size_t *size
, const char v
)
1831 #define TMPBUFLEN 22
1833 * proc_get_long - reads an ASCII formatted integer from a user buffer
1835 * @buf: a kernel buffer
1836 * @size: size of the kernel buffer
1837 * @val: this is where the number will be stored
1838 * @neg: set to %TRUE if number is negative
1839 * @perm_tr: a vector which contains the allowed trailers
1840 * @perm_tr_len: size of the perm_tr vector
1841 * @tr: pointer to store the trailer character
1843 * In case of success %0 is returned and @buf and @size are updated with
1844 * the amount of bytes read. If @tr is non-NULL and a trailing
1845 * character exists (size is non-zero after returning from this
1846 * function), @tr is updated with the trailing character.
1848 static int proc_get_long(char **buf
, size_t *size
,
1849 unsigned long *val
, bool *neg
,
1850 const char *perm_tr
, unsigned perm_tr_len
, char *tr
)
1853 char *p
, tmp
[TMPBUFLEN
];
1859 if (len
> TMPBUFLEN
- 1)
1860 len
= TMPBUFLEN
- 1;
1862 memcpy(tmp
, *buf
, len
);
1866 if (*p
== '-' && *size
> 1) {
1874 *val
= simple_strtoul(p
, &p
, 0);
1878 /* We don't know if the next char is whitespace thus we may accept
1879 * invalid integers (e.g. 1234...a) or two integers instead of one
1880 * (e.g. 123...1). So lets not allow such large numbers. */
1881 if (len
== TMPBUFLEN
- 1)
1884 if (len
< *size
&& perm_tr_len
&& !memchr(perm_tr
, *p
, perm_tr_len
))
1887 if (tr
&& (len
< *size
))
1897 * proc_put_long - converts an integer to a decimal ASCII formatted string
1899 * @buf: the user buffer
1900 * @size: the size of the user buffer
1901 * @val: the integer to be converted
1902 * @neg: sign of the number, %TRUE for negative
1904 * In case of success %0 is returned and @buf and @size are updated with
1905 * the amount of bytes written.
1907 static int proc_put_long(void __user
**buf
, size_t *size
, unsigned long val
,
1911 char tmp
[TMPBUFLEN
], *p
= tmp
;
1913 sprintf(p
, "%s%lu", neg
? "-" : "", val
);
1917 if (copy_to_user(*buf
, tmp
, len
))
1925 static int proc_put_char(void __user
**buf
, size_t *size
, char c
)
1928 char __user
**buffer
= (char __user
**)buf
;
1929 if (put_user(c
, *buffer
))
1931 (*size
)--, (*buffer
)++;
1937 static int do_proc_dointvec_conv(bool *negp
, unsigned long *lvalp
,
1939 int write
, void *data
)
1942 *valp
= *negp
? -*lvalp
: *lvalp
;
1947 *lvalp
= (unsigned long)-val
;
1950 *lvalp
= (unsigned long)val
;
1956 static const char proc_wspace_sep
[] = { ' ', '\t', '\n' };
1958 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
1959 int write
, void __user
*buffer
,
1960 size_t *lenp
, loff_t
*ppos
,
1961 int (*conv
)(bool *negp
, unsigned long *lvalp
, int *valp
,
1962 int write
, void *data
),
1965 int *i
, vleft
, first
= 1, err
= 0;
1966 unsigned long page
= 0;
1970 if (!tbl_data
|| !table
->maxlen
|| !*lenp
|| (*ppos
&& !write
)) {
1975 i
= (int *) tbl_data
;
1976 vleft
= table
->maxlen
/ sizeof(*i
);
1980 conv
= do_proc_dointvec_conv
;
1984 switch (sysctl_writes_strict
) {
1985 case SYSCTL_WRITES_STRICT
:
1987 case SYSCTL_WRITES_WARN
:
1988 warn_sysctl_write(table
);
1995 if (left
> PAGE_SIZE
- 1)
1996 left
= PAGE_SIZE
- 1;
1997 page
= __get_free_page(GFP_TEMPORARY
);
1998 kbuf
= (char *) page
;
2001 if (copy_from_user(kbuf
, buffer
, left
)) {
2008 for (; left
&& vleft
--; i
++, first
=0) {
2013 left
-= proc_skip_spaces(&kbuf
);
2017 err
= proc_get_long(&kbuf
, &left
, &lval
, &neg
,
2019 sizeof(proc_wspace_sep
), NULL
);
2022 if (conv(&neg
, &lval
, i
, 1, data
)) {
2027 if (conv(&neg
, &lval
, i
, 0, data
)) {
2032 err
= proc_put_char(&buffer
, &left
, '\t');
2035 err
= proc_put_long(&buffer
, &left
, lval
, neg
);
2041 if (!write
&& !first
&& left
&& !err
)
2042 err
= proc_put_char(&buffer
, &left
, '\n');
2043 if (write
&& !err
&& left
)
2044 left
-= proc_skip_spaces(&kbuf
);
2049 return err
? : -EINVAL
;
2057 static int do_proc_dointvec(struct ctl_table
*table
, int write
,
2058 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
2059 int (*conv
)(bool *negp
, unsigned long *lvalp
, int *valp
,
2060 int write
, void *data
),
2063 return __do_proc_dointvec(table
->data
, table
, write
,
2064 buffer
, lenp
, ppos
, conv
, data
);
2068 * proc_dointvec - read a vector of integers
2069 * @table: the sysctl table
2070 * @write: %TRUE if this is a write to the sysctl file
2071 * @buffer: the user buffer
2072 * @lenp: the size of the user buffer
2073 * @ppos: file position
2075 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2076 * values from/to the user buffer, treated as an ASCII string.
2078 * Returns 0 on success.
2080 int proc_dointvec(struct ctl_table
*table
, int write
,
2081 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2083 return do_proc_dointvec(table
,write
,buffer
,lenp
,ppos
,
2088 * Taint values can only be increased
2089 * This means we can safely use a temporary.
2091 static int proc_taint(struct ctl_table
*table
, int write
,
2092 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2095 unsigned long tmptaint
= get_taint();
2098 if (write
&& !capable(CAP_SYS_ADMIN
))
2103 err
= proc_doulongvec_minmax(&t
, write
, buffer
, lenp
, ppos
);
2109 * Poor man's atomic or. Not worth adding a primitive
2110 * to everyone's atomic.h for this
2113 for (i
= 0; i
< BITS_PER_LONG
&& tmptaint
>> i
; i
++) {
2114 if ((tmptaint
>> i
) & 1)
2115 add_taint(i
, LOCKDEP_STILL_OK
);
2122 #ifdef CONFIG_PRINTK
2123 static int proc_dointvec_minmax_sysadmin(struct ctl_table
*table
, int write
,
2124 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2126 if (write
&& !capable(CAP_SYS_ADMIN
))
2129 return proc_dointvec_minmax(table
, write
, buffer
, lenp
, ppos
);
2133 struct do_proc_dointvec_minmax_conv_param
{
2138 static int do_proc_dointvec_minmax_conv(bool *negp
, unsigned long *lvalp
,
2140 int write
, void *data
)
2142 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
2144 int val
= *negp
? -*lvalp
: *lvalp
;
2145 if ((param
->min
&& *param
->min
> val
) ||
2146 (param
->max
&& *param
->max
< val
))
2153 *lvalp
= (unsigned long)-val
;
2156 *lvalp
= (unsigned long)val
;
2163 * proc_dointvec_minmax - read a vector of integers with min/max values
2164 * @table: the sysctl table
2165 * @write: %TRUE if this is a write to the sysctl file
2166 * @buffer: the user buffer
2167 * @lenp: the size of the user buffer
2168 * @ppos: file position
2170 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2171 * values from/to the user buffer, treated as an ASCII string.
2173 * This routine will ensure the values are within the range specified by
2174 * table->extra1 (min) and table->extra2 (max).
2176 * Returns 0 on success.
2178 int proc_dointvec_minmax(struct ctl_table
*table
, int write
,
2179 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2181 struct do_proc_dointvec_minmax_conv_param param
= {
2182 .min
= (int *) table
->extra1
,
2183 .max
= (int *) table
->extra2
,
2185 return do_proc_dointvec(table
, write
, buffer
, lenp
, ppos
,
2186 do_proc_dointvec_minmax_conv
, ¶m
);
2189 static void validate_coredump_safety(void)
2191 #ifdef CONFIG_COREDUMP
2192 if (suid_dumpable
== SUID_DUMP_ROOT
&&
2193 core_pattern
[0] != '/' && core_pattern
[0] != '|') {
2194 printk(KERN_WARNING
"Unsafe core_pattern used with "\
2195 "suid_dumpable=2. Pipe handler or fully qualified "\
2196 "core dump path required.\n");
2201 static int proc_dointvec_minmax_coredump(struct ctl_table
*table
, int write
,
2202 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2204 int error
= proc_dointvec_minmax(table
, write
, buffer
, lenp
, ppos
);
2206 validate_coredump_safety();
2210 #ifdef CONFIG_COREDUMP
2211 static int proc_dostring_coredump(struct ctl_table
*table
, int write
,
2212 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2214 int error
= proc_dostring(table
, write
, buffer
, lenp
, ppos
);
2216 validate_coredump_safety();
2221 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
2222 void __user
*buffer
,
2223 size_t *lenp
, loff_t
*ppos
,
2224 unsigned long convmul
,
2225 unsigned long convdiv
)
2227 unsigned long *i
, *min
, *max
;
2228 int vleft
, first
= 1, err
= 0;
2229 unsigned long page
= 0;
2233 if (!data
|| !table
->maxlen
|| !*lenp
|| (*ppos
&& !write
)) {
2238 i
= (unsigned long *) data
;
2239 min
= (unsigned long *) table
->extra1
;
2240 max
= (unsigned long *) table
->extra2
;
2241 vleft
= table
->maxlen
/ sizeof(unsigned long);
2246 switch (sysctl_writes_strict
) {
2247 case SYSCTL_WRITES_STRICT
:
2249 case SYSCTL_WRITES_WARN
:
2250 warn_sysctl_write(table
);
2257 if (left
> PAGE_SIZE
- 1)
2258 left
= PAGE_SIZE
- 1;
2259 page
= __get_free_page(GFP_TEMPORARY
);
2260 kbuf
= (char *) page
;
2263 if (copy_from_user(kbuf
, buffer
, left
)) {
2270 for (; left
&& vleft
--; i
++, first
= 0) {
2276 left
-= proc_skip_spaces(&kbuf
);
2278 err
= proc_get_long(&kbuf
, &left
, &val
, &neg
,
2280 sizeof(proc_wspace_sep
), NULL
);
2285 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2289 val
= convdiv
* (*i
) / convmul
;
2291 err
= proc_put_char(&buffer
, &left
, '\t');
2295 err
= proc_put_long(&buffer
, &left
, val
, false);
2301 if (!write
&& !first
&& left
&& !err
)
2302 err
= proc_put_char(&buffer
, &left
, '\n');
2304 left
-= proc_skip_spaces(&kbuf
);
2309 return err
? : -EINVAL
;
2317 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2318 void __user
*buffer
,
2319 size_t *lenp
, loff_t
*ppos
,
2320 unsigned long convmul
,
2321 unsigned long convdiv
)
2323 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2324 buffer
, lenp
, ppos
, convmul
, convdiv
);
2328 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2329 * @table: the sysctl table
2330 * @write: %TRUE if this is a write to the sysctl file
2331 * @buffer: the user buffer
2332 * @lenp: the size of the user buffer
2333 * @ppos: file position
2335 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2336 * values from/to the user buffer, treated as an ASCII string.
2338 * This routine will ensure the values are within the range specified by
2339 * table->extra1 (min) and table->extra2 (max).
2341 * Returns 0 on success.
2343 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2344 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2346 return do_proc_doulongvec_minmax(table
, write
, buffer
, lenp
, ppos
, 1l, 1l);
2350 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2351 * @table: the sysctl table
2352 * @write: %TRUE if this is a write to the sysctl file
2353 * @buffer: the user buffer
2354 * @lenp: the size of the user buffer
2355 * @ppos: file position
2357 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2358 * values from/to the user buffer, treated as an ASCII string. The values
2359 * are treated as milliseconds, and converted to jiffies when they are stored.
2361 * This routine will ensure the values are within the range specified by
2362 * table->extra1 (min) and table->extra2 (max).
2364 * Returns 0 on success.
2366 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2367 void __user
*buffer
,
2368 size_t *lenp
, loff_t
*ppos
)
2370 return do_proc_doulongvec_minmax(table
, write
, buffer
,
2371 lenp
, ppos
, HZ
, 1000l);
2375 static int do_proc_dointvec_jiffies_conv(bool *negp
, unsigned long *lvalp
,
2377 int write
, void *data
)
2380 if (*lvalp
> LONG_MAX
/ HZ
)
2382 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2388 lval
= (unsigned long)-val
;
2391 lval
= (unsigned long)val
;
2398 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp
, unsigned long *lvalp
,
2400 int write
, void *data
)
2403 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2405 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2411 lval
= (unsigned long)-val
;
2414 lval
= (unsigned long)val
;
2416 *lvalp
= jiffies_to_clock_t(lval
);
2421 static int do_proc_dointvec_ms_jiffies_conv(bool *negp
, unsigned long *lvalp
,
2423 int write
, void *data
)
2426 unsigned long jif
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2436 lval
= (unsigned long)-val
;
2439 lval
= (unsigned long)val
;
2441 *lvalp
= jiffies_to_msecs(lval
);
2447 * proc_dointvec_jiffies - read a vector of integers as seconds
2448 * @table: the sysctl table
2449 * @write: %TRUE if this is a write to the sysctl file
2450 * @buffer: the user buffer
2451 * @lenp: the size of the user buffer
2452 * @ppos: file position
2454 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2455 * values from/to the user buffer, treated as an ASCII string.
2456 * The values read are assumed to be in seconds, and are converted into
2459 * Returns 0 on success.
2461 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
,
2462 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2464 return do_proc_dointvec(table
,write
,buffer
,lenp
,ppos
,
2465 do_proc_dointvec_jiffies_conv
,NULL
);
2469 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2470 * @table: the sysctl table
2471 * @write: %TRUE if this is a write to the sysctl file
2472 * @buffer: the user buffer
2473 * @lenp: the size of the user buffer
2474 * @ppos: pointer to the file position
2476 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2477 * values from/to the user buffer, treated as an ASCII string.
2478 * The values read are assumed to be in 1/USER_HZ seconds, and
2479 * are converted into jiffies.
2481 * Returns 0 on success.
2483 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
,
2484 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2486 return do_proc_dointvec(table
,write
,buffer
,lenp
,ppos
,
2487 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2491 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2492 * @table: the sysctl table
2493 * @write: %TRUE if this is a write to the sysctl file
2494 * @buffer: the user buffer
2495 * @lenp: the size of the user buffer
2496 * @ppos: file position
2497 * @ppos: the current position in the file
2499 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2500 * values from/to the user buffer, treated as an ASCII string.
2501 * The values read are assumed to be in 1/1000 seconds, and
2502 * are converted into jiffies.
2504 * Returns 0 on success.
2506 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
,
2507 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2509 return do_proc_dointvec(table
, write
, buffer
, lenp
, ppos
,
2510 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2513 static int proc_do_cad_pid(struct ctl_table
*table
, int write
,
2514 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2516 struct pid
*new_pid
;
2520 tmp
= pid_vnr(cad_pid
);
2522 r
= __do_proc_dointvec(&tmp
, table
, write
, buffer
,
2523 lenp
, ppos
, NULL
, NULL
);
2527 new_pid
= find_get_pid(tmp
);
2531 put_pid(xchg(&cad_pid
, new_pid
));
2536 * proc_do_large_bitmap - read/write from/to a large bitmap
2537 * @table: the sysctl table
2538 * @write: %TRUE if this is a write to the sysctl file
2539 * @buffer: the user buffer
2540 * @lenp: the size of the user buffer
2541 * @ppos: file position
2543 * The bitmap is stored at table->data and the bitmap length (in bits)
2546 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2547 * large bitmaps may be represented in a compact manner. Writing into
2548 * the file will clear the bitmap then update it with the given input.
2550 * Returns 0 on success.
2552 int proc_do_large_bitmap(struct ctl_table
*table
, int write
,
2553 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2557 size_t left
= *lenp
;
2558 unsigned long bitmap_len
= table
->maxlen
;
2559 unsigned long *bitmap
= *(unsigned long **) table
->data
;
2560 unsigned long *tmp_bitmap
= NULL
;
2561 char tr_a
[] = { '-', ',', '\n' }, tr_b
[] = { ',', '\n', 0 }, c
;
2563 if (!bitmap
|| !bitmap_len
|| !left
|| (*ppos
&& !write
)) {
2569 unsigned long page
= 0;
2572 if (left
> PAGE_SIZE
- 1)
2573 left
= PAGE_SIZE
- 1;
2575 page
= __get_free_page(GFP_TEMPORARY
);
2576 kbuf
= (char *) page
;
2579 if (copy_from_user(kbuf
, buffer
, left
)) {
2585 tmp_bitmap
= kzalloc(BITS_TO_LONGS(bitmap_len
) * sizeof(unsigned long),
2591 proc_skip_char(&kbuf
, &left
, '\n');
2592 while (!err
&& left
) {
2593 unsigned long val_a
, val_b
;
2596 err
= proc_get_long(&kbuf
, &left
, &val_a
, &neg
, tr_a
,
2600 if (val_a
>= bitmap_len
|| neg
) {
2612 err
= proc_get_long(&kbuf
, &left
, &val_b
,
2613 &neg
, tr_b
, sizeof(tr_b
),
2617 if (val_b
>= bitmap_len
|| neg
||
2628 bitmap_set(tmp_bitmap
, val_a
, val_b
- val_a
+ 1);
2630 proc_skip_char(&kbuf
, &left
, '\n');
2634 unsigned long bit_a
, bit_b
= 0;
2637 bit_a
= find_next_bit(bitmap
, bitmap_len
, bit_b
);
2638 if (bit_a
>= bitmap_len
)
2640 bit_b
= find_next_zero_bit(bitmap
, bitmap_len
,
2644 err
= proc_put_char(&buffer
, &left
, ',');
2648 err
= proc_put_long(&buffer
, &left
, bit_a
, false);
2651 if (bit_a
!= bit_b
) {
2652 err
= proc_put_char(&buffer
, &left
, '-');
2655 err
= proc_put_long(&buffer
, &left
, bit_b
, false);
2663 err
= proc_put_char(&buffer
, &left
, '\n');
2669 bitmap_or(bitmap
, bitmap
, tmp_bitmap
, bitmap_len
);
2671 bitmap_copy(bitmap
, tmp_bitmap
, bitmap_len
);
2683 #else /* CONFIG_PROC_SYSCTL */
2685 int proc_dostring(struct ctl_table
*table
, int write
,
2686 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2691 int proc_dointvec(struct ctl_table
*table
, int write
,
2692 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2697 int proc_dointvec_minmax(struct ctl_table
*table
, int write
,
2698 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2703 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
,
2704 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2709 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
,
2710 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2715 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
,
2716 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2721 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2722 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2727 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2728 void __user
*buffer
,
2729 size_t *lenp
, loff_t
*ppos
)
2735 #endif /* CONFIG_PROC_SYSCTL */
2738 * No sense putting this after each symbol definition, twice,
2739 * exception granted :-)
2741 EXPORT_SYMBOL(proc_dointvec
);
2742 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2743 EXPORT_SYMBOL(proc_dointvec_minmax
);
2744 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2745 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2746 EXPORT_SYMBOL(proc_dostring
);
2747 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2748 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);