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
,
393 .procname
= "numa_balancing",
394 .data
= NULL
, /* filled in by handler */
395 .maxlen
= sizeof(unsigned int),
397 .proc_handler
= sysctl_numa_balancing
,
401 #endif /* CONFIG_NUMA_BALANCING */
402 #endif /* CONFIG_SCHED_DEBUG */
404 .procname
= "sched_rt_period_us",
405 .data
= &sysctl_sched_rt_period
,
406 .maxlen
= sizeof(unsigned int),
408 .proc_handler
= sched_rt_handler
,
411 .procname
= "sched_rt_runtime_us",
412 .data
= &sysctl_sched_rt_runtime
,
413 .maxlen
= sizeof(int),
415 .proc_handler
= sched_rt_handler
,
418 .procname
= "sched_rr_timeslice_ms",
419 .data
= &sched_rr_timeslice
,
420 .maxlen
= sizeof(int),
422 .proc_handler
= sched_rr_handler
,
424 #ifdef CONFIG_SCHED_AUTOGROUP
426 .procname
= "sched_autogroup_enabled",
427 .data
= &sysctl_sched_autogroup_enabled
,
428 .maxlen
= sizeof(unsigned int),
430 .proc_handler
= proc_dointvec_minmax
,
435 #ifdef CONFIG_CFS_BANDWIDTH
437 .procname
= "sched_cfs_bandwidth_slice_us",
438 .data
= &sysctl_sched_cfs_bandwidth_slice
,
439 .maxlen
= sizeof(unsigned int),
441 .proc_handler
= proc_dointvec_minmax
,
445 #ifdef CONFIG_PROVE_LOCKING
447 .procname
= "prove_locking",
448 .data
= &prove_locking
,
449 .maxlen
= sizeof(int),
451 .proc_handler
= proc_dointvec
,
454 #ifdef CONFIG_LOCK_STAT
456 .procname
= "lock_stat",
458 .maxlen
= sizeof(int),
460 .proc_handler
= proc_dointvec
,
465 .data
= &panic_timeout
,
466 .maxlen
= sizeof(int),
468 .proc_handler
= proc_dointvec
,
470 #ifdef CONFIG_COREDUMP
472 .procname
= "core_uses_pid",
473 .data
= &core_uses_pid
,
474 .maxlen
= sizeof(int),
476 .proc_handler
= proc_dointvec
,
479 .procname
= "core_pattern",
480 .data
= core_pattern
,
481 .maxlen
= CORENAME_MAX_SIZE
,
483 .proc_handler
= proc_dostring_coredump
,
486 .procname
= "core_pipe_limit",
487 .data
= &core_pipe_limit
,
488 .maxlen
= sizeof(unsigned int),
490 .proc_handler
= proc_dointvec
,
493 #ifdef CONFIG_PROC_SYSCTL
495 .procname
= "tainted",
496 .maxlen
= sizeof(long),
498 .proc_handler
= proc_taint
,
501 .procname
= "sysctl_writes_strict",
502 .data
= &sysctl_writes_strict
,
503 .maxlen
= sizeof(int),
505 .proc_handler
= proc_dointvec_minmax
,
510 #ifdef CONFIG_LATENCYTOP
512 .procname
= "latencytop",
513 .data
= &latencytop_enabled
,
514 .maxlen
= sizeof(int),
516 .proc_handler
= proc_dointvec
,
519 #ifdef CONFIG_BLK_DEV_INITRD
521 .procname
= "real-root-dev",
522 .data
= &real_root_dev
,
523 .maxlen
= sizeof(int),
525 .proc_handler
= proc_dointvec
,
529 .procname
= "print-fatal-signals",
530 .data
= &print_fatal_signals
,
531 .maxlen
= sizeof(int),
533 .proc_handler
= proc_dointvec
,
537 .procname
= "reboot-cmd",
538 .data
= reboot_command
,
541 .proc_handler
= proc_dostring
,
544 .procname
= "stop-a",
545 .data
= &stop_a_enabled
,
546 .maxlen
= sizeof (int),
548 .proc_handler
= proc_dointvec
,
551 .procname
= "scons-poweroff",
552 .data
= &scons_pwroff
,
553 .maxlen
= sizeof (int),
555 .proc_handler
= proc_dointvec
,
558 #ifdef CONFIG_SPARC64
560 .procname
= "tsb-ratio",
561 .data
= &sysctl_tsb_ratio
,
562 .maxlen
= sizeof (int),
564 .proc_handler
= proc_dointvec
,
569 .procname
= "soft-power",
570 .data
= &pwrsw_enabled
,
571 .maxlen
= sizeof (int),
573 .proc_handler
= proc_dointvec
,
576 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
578 .procname
= "unaligned-trap",
579 .data
= &unaligned_enabled
,
580 .maxlen
= sizeof (int),
582 .proc_handler
= proc_dointvec
,
586 .procname
= "ctrl-alt-del",
588 .maxlen
= sizeof(int),
590 .proc_handler
= proc_dointvec
,
592 #ifdef CONFIG_FUNCTION_TRACER
594 .procname
= "ftrace_enabled",
595 .data
= &ftrace_enabled
,
596 .maxlen
= sizeof(int),
598 .proc_handler
= ftrace_enable_sysctl
,
601 #ifdef CONFIG_STACK_TRACER
603 .procname
= "stack_tracer_enabled",
604 .data
= &stack_tracer_enabled
,
605 .maxlen
= sizeof(int),
607 .proc_handler
= stack_trace_sysctl
,
610 #ifdef CONFIG_TRACING
612 .procname
= "ftrace_dump_on_oops",
613 .data
= &ftrace_dump_on_oops
,
614 .maxlen
= sizeof(int),
616 .proc_handler
= proc_dointvec
,
619 .procname
= "traceoff_on_warning",
620 .data
= &__disable_trace_on_warning
,
621 .maxlen
= sizeof(__disable_trace_on_warning
),
623 .proc_handler
= proc_dointvec
,
628 .procname
= "kexec_load_disabled",
629 .data
= &kexec_load_disabled
,
630 .maxlen
= sizeof(int),
632 /* only handle a transition from default "0" to "1" */
633 .proc_handler
= proc_dointvec_minmax
,
638 #ifdef CONFIG_MODULES
640 .procname
= "modprobe",
641 .data
= &modprobe_path
,
642 .maxlen
= KMOD_PATH_LEN
,
644 .proc_handler
= proc_dostring
,
647 .procname
= "modules_disabled",
648 .data
= &modules_disabled
,
649 .maxlen
= sizeof(int),
651 /* only handle a transition from default "0" to "1" */
652 .proc_handler
= proc_dointvec_minmax
,
657 #ifdef CONFIG_UEVENT_HELPER
659 .procname
= "hotplug",
660 .data
= &uevent_helper
,
661 .maxlen
= UEVENT_HELPER_PATH_LEN
,
663 .proc_handler
= proc_dostring
,
666 #ifdef CONFIG_CHR_DEV_SG
668 .procname
= "sg-big-buff",
669 .data
= &sg_big_buff
,
670 .maxlen
= sizeof (int),
672 .proc_handler
= proc_dointvec
,
675 #ifdef CONFIG_BSD_PROCESS_ACCT
679 .maxlen
= 3*sizeof(int),
681 .proc_handler
= proc_dointvec
,
684 #ifdef CONFIG_MAGIC_SYSRQ
687 .data
= &__sysrq_enabled
,
688 .maxlen
= sizeof (int),
690 .proc_handler
= sysrq_sysctl_handler
,
693 #ifdef CONFIG_PROC_SYSCTL
695 .procname
= "cad_pid",
697 .maxlen
= sizeof (int),
699 .proc_handler
= proc_do_cad_pid
,
703 .procname
= "threads-max",
704 .data
= &max_threads
,
705 .maxlen
= sizeof(int),
707 .proc_handler
= proc_dointvec
,
710 .procname
= "random",
712 .child
= random_table
,
715 .procname
= "usermodehelper",
717 .child
= usermodehelper_table
,
720 .procname
= "overflowuid",
721 .data
= &overflowuid
,
722 .maxlen
= sizeof(int),
724 .proc_handler
= proc_dointvec_minmax
,
725 .extra1
= &minolduid
,
726 .extra2
= &maxolduid
,
729 .procname
= "overflowgid",
730 .data
= &overflowgid
,
731 .maxlen
= sizeof(int),
733 .proc_handler
= proc_dointvec_minmax
,
734 .extra1
= &minolduid
,
735 .extra2
= &maxolduid
,
738 #ifdef CONFIG_MATHEMU
740 .procname
= "ieee_emulation_warnings",
741 .data
= &sysctl_ieee_emulation_warnings
,
742 .maxlen
= sizeof(int),
744 .proc_handler
= proc_dointvec
,
748 .procname
= "userprocess_debug",
749 .data
= &show_unhandled_signals
,
750 .maxlen
= sizeof(int),
752 .proc_handler
= proc_dointvec
,
756 .procname
= "pid_max",
758 .maxlen
= sizeof (int),
760 .proc_handler
= proc_dointvec_minmax
,
761 .extra1
= &pid_max_min
,
762 .extra2
= &pid_max_max
,
765 .procname
= "panic_on_oops",
766 .data
= &panic_on_oops
,
767 .maxlen
= sizeof(int),
769 .proc_handler
= proc_dointvec
,
771 #if defined CONFIG_PRINTK
773 .procname
= "printk",
774 .data
= &console_loglevel
,
775 .maxlen
= 4*sizeof(int),
777 .proc_handler
= proc_dointvec
,
780 .procname
= "printk_ratelimit",
781 .data
= &printk_ratelimit_state
.interval
,
782 .maxlen
= sizeof(int),
784 .proc_handler
= proc_dointvec_jiffies
,
787 .procname
= "printk_ratelimit_burst",
788 .data
= &printk_ratelimit_state
.burst
,
789 .maxlen
= sizeof(int),
791 .proc_handler
= proc_dointvec
,
794 .procname
= "printk_delay",
795 .data
= &printk_delay_msec
,
796 .maxlen
= sizeof(int),
798 .proc_handler
= proc_dointvec_minmax
,
800 .extra2
= &ten_thousand
,
803 .procname
= "dmesg_restrict",
804 .data
= &dmesg_restrict
,
805 .maxlen
= sizeof(int),
807 .proc_handler
= proc_dointvec_minmax_sysadmin
,
812 .procname
= "kptr_restrict",
813 .data
= &kptr_restrict
,
814 .maxlen
= sizeof(int),
816 .proc_handler
= proc_dointvec_minmax_sysadmin
,
822 .procname
= "ngroups_max",
823 .data
= &ngroups_max
,
824 .maxlen
= sizeof (int),
826 .proc_handler
= proc_dointvec
,
829 .procname
= "cap_last_cap",
830 .data
= (void *)&cap_last_cap
,
831 .maxlen
= sizeof(int),
833 .proc_handler
= proc_dointvec
,
835 #if defined(CONFIG_LOCKUP_DETECTOR)
837 .procname
= "watchdog",
838 .data
= &watchdog_user_enabled
,
839 .maxlen
= sizeof (int),
841 .proc_handler
= proc_dowatchdog
,
846 .procname
= "watchdog_thresh",
847 .data
= &watchdog_thresh
,
848 .maxlen
= sizeof(int),
850 .proc_handler
= proc_dowatchdog
,
855 .procname
= "softlockup_panic",
856 .data
= &softlockup_panic
,
857 .maxlen
= sizeof(int),
859 .proc_handler
= proc_dointvec_minmax
,
865 .procname
= "softlockup_all_cpu_backtrace",
866 .data
= &sysctl_softlockup_all_cpu_backtrace
,
867 .maxlen
= sizeof(int),
869 .proc_handler
= proc_dointvec_minmax
,
873 #endif /* CONFIG_SMP */
875 .procname
= "nmi_watchdog",
876 .data
= &watchdog_user_enabled
,
877 .maxlen
= sizeof (int),
879 .proc_handler
= proc_dowatchdog
,
884 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
886 .procname
= "unknown_nmi_panic",
887 .data
= &unknown_nmi_panic
,
888 .maxlen
= sizeof (int),
890 .proc_handler
= proc_dointvec
,
893 #if defined(CONFIG_X86)
895 .procname
= "panic_on_unrecovered_nmi",
896 .data
= &panic_on_unrecovered_nmi
,
897 .maxlen
= sizeof(int),
899 .proc_handler
= proc_dointvec
,
902 .procname
= "panic_on_io_nmi",
903 .data
= &panic_on_io_nmi
,
904 .maxlen
= sizeof(int),
906 .proc_handler
= proc_dointvec
,
908 #ifdef CONFIG_DEBUG_STACKOVERFLOW
910 .procname
= "panic_on_stackoverflow",
911 .data
= &sysctl_panic_on_stackoverflow
,
912 .maxlen
= sizeof(int),
914 .proc_handler
= proc_dointvec
,
918 .procname
= "bootloader_type",
919 .data
= &bootloader_type
,
920 .maxlen
= sizeof (int),
922 .proc_handler
= proc_dointvec
,
925 .procname
= "bootloader_version",
926 .data
= &bootloader_version
,
927 .maxlen
= sizeof (int),
929 .proc_handler
= proc_dointvec
,
932 .procname
= "kstack_depth_to_print",
933 .data
= &kstack_depth_to_print
,
934 .maxlen
= sizeof(int),
936 .proc_handler
= proc_dointvec
,
939 .procname
= "io_delay_type",
940 .data
= &io_delay_type
,
941 .maxlen
= sizeof(int),
943 .proc_handler
= proc_dointvec
,
946 #if defined(CONFIG_MMU)
948 .procname
= "randomize_va_space",
949 .data
= &randomize_va_space
,
950 .maxlen
= sizeof(int),
952 .proc_handler
= proc_dointvec
,
955 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
957 .procname
= "spin_retry",
959 .maxlen
= sizeof (int),
961 .proc_handler
= proc_dointvec
,
964 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
966 .procname
= "acpi_video_flags",
967 .data
= &acpi_realmode_flags
,
968 .maxlen
= sizeof (unsigned long),
970 .proc_handler
= proc_doulongvec_minmax
,
973 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
975 .procname
= "ignore-unaligned-usertrap",
976 .data
= &no_unaligned_warning
,
977 .maxlen
= sizeof (int),
979 .proc_handler
= proc_dointvec
,
984 .procname
= "unaligned-dump-stack",
985 .data
= &unaligned_dump_stack
,
986 .maxlen
= sizeof (int),
988 .proc_handler
= proc_dointvec
,
991 #ifdef CONFIG_DETECT_HUNG_TASK
993 .procname
= "hung_task_panic",
994 .data
= &sysctl_hung_task_panic
,
995 .maxlen
= sizeof(int),
997 .proc_handler
= proc_dointvec_minmax
,
1002 .procname
= "hung_task_check_count",
1003 .data
= &sysctl_hung_task_check_count
,
1004 .maxlen
= sizeof(int),
1006 .proc_handler
= proc_dointvec_minmax
,
1010 .procname
= "hung_task_timeout_secs",
1011 .data
= &sysctl_hung_task_timeout_secs
,
1012 .maxlen
= sizeof(unsigned long),
1014 .proc_handler
= proc_dohung_task_timeout_secs
,
1015 .extra2
= &hung_task_timeout_max
,
1018 .procname
= "hung_task_warnings",
1019 .data
= &sysctl_hung_task_warnings
,
1020 .maxlen
= sizeof(int),
1022 .proc_handler
= proc_dointvec_minmax
,
1026 #ifdef CONFIG_COMPAT
1028 .procname
= "compat-log",
1029 .data
= &compat_log
,
1030 .maxlen
= sizeof (int),
1032 .proc_handler
= proc_dointvec
,
1035 #ifdef CONFIG_RT_MUTEXES
1037 .procname
= "max_lock_depth",
1038 .data
= &max_lock_depth
,
1039 .maxlen
= sizeof(int),
1041 .proc_handler
= proc_dointvec
,
1045 .procname
= "poweroff_cmd",
1046 .data
= &poweroff_cmd
,
1047 .maxlen
= POWEROFF_CMD_PATH_LEN
,
1049 .proc_handler
= proc_dostring
,
1055 .child
= key_sysctls
,
1058 #ifdef CONFIG_RCU_TORTURE_TEST
1060 .procname
= "rcutorture_runnable",
1061 .data
= &rcutorture_runnable
,
1062 .maxlen
= sizeof(int),
1064 .proc_handler
= proc_dointvec
,
1067 #ifdef CONFIG_PERF_EVENTS
1069 * User-space scripts rely on the existence of this file
1070 * as a feature check for perf_events being enabled.
1072 * So it's an ABI, do not remove!
1075 .procname
= "perf_event_paranoid",
1076 .data
= &sysctl_perf_event_paranoid
,
1077 .maxlen
= sizeof(sysctl_perf_event_paranoid
),
1079 .proc_handler
= proc_dointvec
,
1082 .procname
= "perf_event_mlock_kb",
1083 .data
= &sysctl_perf_event_mlock
,
1084 .maxlen
= sizeof(sysctl_perf_event_mlock
),
1086 .proc_handler
= proc_dointvec
,
1089 .procname
= "perf_event_max_sample_rate",
1090 .data
= &sysctl_perf_event_sample_rate
,
1091 .maxlen
= sizeof(sysctl_perf_event_sample_rate
),
1093 .proc_handler
= perf_proc_update_handler
,
1097 .procname
= "perf_cpu_time_max_percent",
1098 .data
= &sysctl_perf_cpu_time_max_percent
,
1099 .maxlen
= sizeof(sysctl_perf_cpu_time_max_percent
),
1101 .proc_handler
= perf_cpu_time_max_percent_handler
,
1103 .extra2
= &one_hundred
,
1106 #ifdef CONFIG_KMEMCHECK
1108 .procname
= "kmemcheck",
1109 .data
= &kmemcheck_enabled
,
1110 .maxlen
= sizeof(int),
1112 .proc_handler
= proc_dointvec
,
1118 static struct ctl_table vm_table
[] = {
1120 .procname
= "overcommit_memory",
1121 .data
= &sysctl_overcommit_memory
,
1122 .maxlen
= sizeof(sysctl_overcommit_memory
),
1124 .proc_handler
= proc_dointvec_minmax
,
1129 .procname
= "panic_on_oom",
1130 .data
= &sysctl_panic_on_oom
,
1131 .maxlen
= sizeof(sysctl_panic_on_oom
),
1133 .proc_handler
= proc_dointvec_minmax
,
1138 .procname
= "oom_kill_allocating_task",
1139 .data
= &sysctl_oom_kill_allocating_task
,
1140 .maxlen
= sizeof(sysctl_oom_kill_allocating_task
),
1142 .proc_handler
= proc_dointvec
,
1145 .procname
= "oom_dump_tasks",
1146 .data
= &sysctl_oom_dump_tasks
,
1147 .maxlen
= sizeof(sysctl_oom_dump_tasks
),
1149 .proc_handler
= proc_dointvec
,
1152 .procname
= "overcommit_ratio",
1153 .data
= &sysctl_overcommit_ratio
,
1154 .maxlen
= sizeof(sysctl_overcommit_ratio
),
1156 .proc_handler
= overcommit_ratio_handler
,
1159 .procname
= "overcommit_kbytes",
1160 .data
= &sysctl_overcommit_kbytes
,
1161 .maxlen
= sizeof(sysctl_overcommit_kbytes
),
1163 .proc_handler
= overcommit_kbytes_handler
,
1166 .procname
= "page-cluster",
1167 .data
= &page_cluster
,
1168 .maxlen
= sizeof(int),
1170 .proc_handler
= proc_dointvec_minmax
,
1174 .procname
= "dirty_background_ratio",
1175 .data
= &dirty_background_ratio
,
1176 .maxlen
= sizeof(dirty_background_ratio
),
1178 .proc_handler
= dirty_background_ratio_handler
,
1180 .extra2
= &one_hundred
,
1183 .procname
= "dirty_background_bytes",
1184 .data
= &dirty_background_bytes
,
1185 .maxlen
= sizeof(dirty_background_bytes
),
1187 .proc_handler
= dirty_background_bytes_handler
,
1191 .procname
= "dirty_ratio",
1192 .data
= &vm_dirty_ratio
,
1193 .maxlen
= sizeof(vm_dirty_ratio
),
1195 .proc_handler
= dirty_ratio_handler
,
1197 .extra2
= &one_hundred
,
1200 .procname
= "dirty_bytes",
1201 .data
= &vm_dirty_bytes
,
1202 .maxlen
= sizeof(vm_dirty_bytes
),
1204 .proc_handler
= dirty_bytes_handler
,
1205 .extra1
= &dirty_bytes_min
,
1208 .procname
= "dirty_writeback_centisecs",
1209 .data
= &dirty_writeback_interval
,
1210 .maxlen
= sizeof(dirty_writeback_interval
),
1212 .proc_handler
= dirty_writeback_centisecs_handler
,
1215 .procname
= "dirty_expire_centisecs",
1216 .data
= &dirty_expire_interval
,
1217 .maxlen
= sizeof(dirty_expire_interval
),
1219 .proc_handler
= proc_dointvec_minmax
,
1223 .procname
= "nr_pdflush_threads",
1224 .mode
= 0444 /* read-only */,
1225 .proc_handler
= pdflush_proc_obsolete
,
1228 .procname
= "swappiness",
1229 .data
= &vm_swappiness
,
1230 .maxlen
= sizeof(vm_swappiness
),
1232 .proc_handler
= proc_dointvec_minmax
,
1234 .extra2
= &one_hundred
,
1236 #ifdef CONFIG_HUGETLB_PAGE
1238 .procname
= "nr_hugepages",
1240 .maxlen
= sizeof(unsigned long),
1242 .proc_handler
= hugetlb_sysctl_handler
,
1243 .extra1
= (void *)&hugetlb_zero
,
1244 .extra2
= (void *)&hugetlb_infinity
,
1248 .procname
= "nr_hugepages_mempolicy",
1250 .maxlen
= sizeof(unsigned long),
1252 .proc_handler
= &hugetlb_mempolicy_sysctl_handler
,
1253 .extra1
= (void *)&hugetlb_zero
,
1254 .extra2
= (void *)&hugetlb_infinity
,
1258 .procname
= "hugetlb_shm_group",
1259 .data
= &sysctl_hugetlb_shm_group
,
1260 .maxlen
= sizeof(gid_t
),
1262 .proc_handler
= proc_dointvec
,
1265 .procname
= "hugepages_treat_as_movable",
1266 .data
= &hugepages_treat_as_movable
,
1267 .maxlen
= sizeof(int),
1269 .proc_handler
= proc_dointvec
,
1272 .procname
= "nr_overcommit_hugepages",
1274 .maxlen
= sizeof(unsigned long),
1276 .proc_handler
= hugetlb_overcommit_handler
,
1277 .extra1
= (void *)&hugetlb_zero
,
1278 .extra2
= (void *)&hugetlb_infinity
,
1282 .procname
= "lowmem_reserve_ratio",
1283 .data
= &sysctl_lowmem_reserve_ratio
,
1284 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
1286 .proc_handler
= lowmem_reserve_ratio_sysctl_handler
,
1289 .procname
= "drop_caches",
1290 .data
= &sysctl_drop_caches
,
1291 .maxlen
= sizeof(int),
1293 .proc_handler
= drop_caches_sysctl_handler
,
1297 #ifdef CONFIG_COMPACTION
1299 .procname
= "compact_memory",
1300 .data
= &sysctl_compact_memory
,
1301 .maxlen
= sizeof(int),
1303 .proc_handler
= sysctl_compaction_handler
,
1306 .procname
= "extfrag_threshold",
1307 .data
= &sysctl_extfrag_threshold
,
1308 .maxlen
= sizeof(int),
1310 .proc_handler
= sysctl_extfrag_handler
,
1311 .extra1
= &min_extfrag_threshold
,
1312 .extra2
= &max_extfrag_threshold
,
1315 #endif /* CONFIG_COMPACTION */
1317 .procname
= "min_free_kbytes",
1318 .data
= &min_free_kbytes
,
1319 .maxlen
= sizeof(min_free_kbytes
),
1321 .proc_handler
= min_free_kbytes_sysctl_handler
,
1325 .procname
= "percpu_pagelist_fraction",
1326 .data
= &percpu_pagelist_fraction
,
1327 .maxlen
= sizeof(percpu_pagelist_fraction
),
1329 .proc_handler
= percpu_pagelist_fraction_sysctl_handler
,
1334 .procname
= "max_map_count",
1335 .data
= &sysctl_max_map_count
,
1336 .maxlen
= sizeof(sysctl_max_map_count
),
1338 .proc_handler
= proc_dointvec_minmax
,
1343 .procname
= "nr_trim_pages",
1344 .data
= &sysctl_nr_trim_pages
,
1345 .maxlen
= sizeof(sysctl_nr_trim_pages
),
1347 .proc_handler
= proc_dointvec_minmax
,
1352 .procname
= "laptop_mode",
1353 .data
= &laptop_mode
,
1354 .maxlen
= sizeof(laptop_mode
),
1356 .proc_handler
= proc_dointvec_jiffies
,
1359 .procname
= "block_dump",
1360 .data
= &block_dump
,
1361 .maxlen
= sizeof(block_dump
),
1363 .proc_handler
= proc_dointvec
,
1367 .procname
= "vfs_cache_pressure",
1368 .data
= &sysctl_vfs_cache_pressure
,
1369 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
1371 .proc_handler
= proc_dointvec
,
1374 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1376 .procname
= "legacy_va_layout",
1377 .data
= &sysctl_legacy_va_layout
,
1378 .maxlen
= sizeof(sysctl_legacy_va_layout
),
1380 .proc_handler
= proc_dointvec
,
1386 .procname
= "zone_reclaim_mode",
1387 .data
= &zone_reclaim_mode
,
1388 .maxlen
= sizeof(zone_reclaim_mode
),
1390 .proc_handler
= proc_dointvec
,
1394 .procname
= "min_unmapped_ratio",
1395 .data
= &sysctl_min_unmapped_ratio
,
1396 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
1398 .proc_handler
= sysctl_min_unmapped_ratio_sysctl_handler
,
1400 .extra2
= &one_hundred
,
1403 .procname
= "min_slab_ratio",
1404 .data
= &sysctl_min_slab_ratio
,
1405 .maxlen
= sizeof(sysctl_min_slab_ratio
),
1407 .proc_handler
= sysctl_min_slab_ratio_sysctl_handler
,
1409 .extra2
= &one_hundred
,
1414 .procname
= "stat_interval",
1415 .data
= &sysctl_stat_interval
,
1416 .maxlen
= sizeof(sysctl_stat_interval
),
1418 .proc_handler
= proc_dointvec_jiffies
,
1423 .procname
= "mmap_min_addr",
1424 .data
= &dac_mmap_min_addr
,
1425 .maxlen
= sizeof(unsigned long),
1427 .proc_handler
= mmap_min_addr_handler
,
1432 .procname
= "numa_zonelist_order",
1433 .data
= &numa_zonelist_order
,
1434 .maxlen
= NUMA_ZONELIST_ORDER_LEN
,
1436 .proc_handler
= numa_zonelist_order_handler
,
1439 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1440 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1442 .procname
= "vdso_enabled",
1443 #ifdef CONFIG_X86_32
1444 .data
= &vdso32_enabled
,
1445 .maxlen
= sizeof(vdso32_enabled
),
1447 .data
= &vdso_enabled
,
1448 .maxlen
= sizeof(vdso_enabled
),
1451 .proc_handler
= proc_dointvec
,
1455 #ifdef CONFIG_HIGHMEM
1457 .procname
= "highmem_is_dirtyable",
1458 .data
= &vm_highmem_is_dirtyable
,
1459 .maxlen
= sizeof(vm_highmem_is_dirtyable
),
1461 .proc_handler
= proc_dointvec_minmax
,
1467 .procname
= "scan_unevictable_pages",
1468 .data
= &scan_unevictable_pages
,
1469 .maxlen
= sizeof(scan_unevictable_pages
),
1471 .proc_handler
= scan_unevictable_handler
,
1473 #ifdef CONFIG_MEMORY_FAILURE
1475 .procname
= "memory_failure_early_kill",
1476 .data
= &sysctl_memory_failure_early_kill
,
1477 .maxlen
= sizeof(sysctl_memory_failure_early_kill
),
1479 .proc_handler
= proc_dointvec_minmax
,
1484 .procname
= "memory_failure_recovery",
1485 .data
= &sysctl_memory_failure_recovery
,
1486 .maxlen
= sizeof(sysctl_memory_failure_recovery
),
1488 .proc_handler
= proc_dointvec_minmax
,
1494 .procname
= "user_reserve_kbytes",
1495 .data
= &sysctl_user_reserve_kbytes
,
1496 .maxlen
= sizeof(sysctl_user_reserve_kbytes
),
1498 .proc_handler
= proc_doulongvec_minmax
,
1501 .procname
= "admin_reserve_kbytes",
1502 .data
= &sysctl_admin_reserve_kbytes
,
1503 .maxlen
= sizeof(sysctl_admin_reserve_kbytes
),
1505 .proc_handler
= proc_doulongvec_minmax
,
1510 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1511 static struct ctl_table binfmt_misc_table
[] = {
1516 static struct ctl_table fs_table
[] = {
1518 .procname
= "inode-nr",
1519 .data
= &inodes_stat
,
1520 .maxlen
= 2*sizeof(long),
1522 .proc_handler
= proc_nr_inodes
,
1525 .procname
= "inode-state",
1526 .data
= &inodes_stat
,
1527 .maxlen
= 7*sizeof(long),
1529 .proc_handler
= proc_nr_inodes
,
1532 .procname
= "file-nr",
1533 .data
= &files_stat
,
1534 .maxlen
= sizeof(files_stat
),
1536 .proc_handler
= proc_nr_files
,
1539 .procname
= "file-max",
1540 .data
= &files_stat
.max_files
,
1541 .maxlen
= sizeof(files_stat
.max_files
),
1543 .proc_handler
= proc_doulongvec_minmax
,
1546 .procname
= "nr_open",
1547 .data
= &sysctl_nr_open
,
1548 .maxlen
= sizeof(int),
1550 .proc_handler
= proc_dointvec_minmax
,
1551 .extra1
= &sysctl_nr_open_min
,
1552 .extra2
= &sysctl_nr_open_max
,
1555 .procname
= "dentry-state",
1556 .data
= &dentry_stat
,
1557 .maxlen
= 6*sizeof(long),
1559 .proc_handler
= proc_nr_dentry
,
1562 .procname
= "overflowuid",
1563 .data
= &fs_overflowuid
,
1564 .maxlen
= sizeof(int),
1566 .proc_handler
= proc_dointvec_minmax
,
1567 .extra1
= &minolduid
,
1568 .extra2
= &maxolduid
,
1571 .procname
= "overflowgid",
1572 .data
= &fs_overflowgid
,
1573 .maxlen
= sizeof(int),
1575 .proc_handler
= proc_dointvec_minmax
,
1576 .extra1
= &minolduid
,
1577 .extra2
= &maxolduid
,
1579 #ifdef CONFIG_FILE_LOCKING
1581 .procname
= "leases-enable",
1582 .data
= &leases_enable
,
1583 .maxlen
= sizeof(int),
1585 .proc_handler
= proc_dointvec
,
1588 #ifdef CONFIG_DNOTIFY
1590 .procname
= "dir-notify-enable",
1591 .data
= &dir_notify_enable
,
1592 .maxlen
= sizeof(int),
1594 .proc_handler
= proc_dointvec
,
1598 #ifdef CONFIG_FILE_LOCKING
1600 .procname
= "lease-break-time",
1601 .data
= &lease_break_time
,
1602 .maxlen
= sizeof(int),
1604 .proc_handler
= proc_dointvec
,
1609 .procname
= "aio-nr",
1611 .maxlen
= sizeof(aio_nr
),
1613 .proc_handler
= proc_doulongvec_minmax
,
1616 .procname
= "aio-max-nr",
1617 .data
= &aio_max_nr
,
1618 .maxlen
= sizeof(aio_max_nr
),
1620 .proc_handler
= proc_doulongvec_minmax
,
1622 #endif /* CONFIG_AIO */
1623 #ifdef CONFIG_INOTIFY_USER
1625 .procname
= "inotify",
1627 .child
= inotify_table
,
1632 .procname
= "epoll",
1634 .child
= epoll_table
,
1639 .procname
= "protected_symlinks",
1640 .data
= &sysctl_protected_symlinks
,
1641 .maxlen
= sizeof(int),
1643 .proc_handler
= proc_dointvec_minmax
,
1648 .procname
= "protected_hardlinks",
1649 .data
= &sysctl_protected_hardlinks
,
1650 .maxlen
= sizeof(int),
1652 .proc_handler
= proc_dointvec_minmax
,
1657 .procname
= "suid_dumpable",
1658 .data
= &suid_dumpable
,
1659 .maxlen
= sizeof(int),
1661 .proc_handler
= proc_dointvec_minmax_coredump
,
1665 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1667 .procname
= "binfmt_misc",
1669 .child
= binfmt_misc_table
,
1673 .procname
= "pipe-max-size",
1674 .data
= &pipe_max_size
,
1675 .maxlen
= sizeof(int),
1677 .proc_handler
= &pipe_proc_fn
,
1678 .extra1
= &pipe_min_size
,
1683 static struct ctl_table debug_table
[] = {
1684 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1686 .procname
= "exception-trace",
1687 .data
= &show_unhandled_signals
,
1688 .maxlen
= sizeof(int),
1690 .proc_handler
= proc_dointvec
1693 #if defined(CONFIG_OPTPROBES)
1695 .procname
= "kprobes-optimization",
1696 .data
= &sysctl_kprobes_optimization
,
1697 .maxlen
= sizeof(int),
1699 .proc_handler
= proc_kprobes_optimization_handler
,
1707 static struct ctl_table dev_table
[] = {
1711 int __init
sysctl_init(void)
1713 struct ctl_table_header
*hdr
;
1715 hdr
= register_sysctl_table(sysctl_base_table
);
1716 kmemleak_not_leak(hdr
);
1720 #endif /* CONFIG_SYSCTL */
1726 #ifdef CONFIG_PROC_SYSCTL
1728 static int _proc_do_string(char *data
, int maxlen
, int write
,
1729 char __user
*buffer
,
1730 size_t *lenp
, loff_t
*ppos
)
1736 if (!data
|| !maxlen
|| !*lenp
) {
1742 if (sysctl_writes_strict
== SYSCTL_WRITES_STRICT
) {
1743 /* Only continue writes not past the end of buffer. */
1745 if (len
> maxlen
- 1)
1752 /* Start writing from beginning of buffer. */
1758 while ((p
- buffer
) < *lenp
&& len
< maxlen
- 1) {
1759 if (get_user(c
, p
++))
1761 if (c
== 0 || c
== '\n')
1782 if (copy_to_user(buffer
, data
, len
))
1785 if (put_user('\n', buffer
+ len
))
1795 static void warn_sysctl_write(struct ctl_table
*table
)
1797 pr_warn_once("%s wrote to %s when file position was not 0!\n"
1798 "This will not be supported in the future. To silence this\n"
1799 "warning, set kernel.sysctl_writes_strict = -1\n",
1800 current
->comm
, table
->procname
);
1804 * proc_dostring - read a string sysctl
1805 * @table: the sysctl table
1806 * @write: %TRUE if this is a write to the sysctl file
1807 * @buffer: the user buffer
1808 * @lenp: the size of the user buffer
1809 * @ppos: file position
1811 * Reads/writes a string from/to the user buffer. If the kernel
1812 * buffer provided is not large enough to hold the string, the
1813 * string is truncated. The copied string is %NULL-terminated.
1814 * If the string is being read by the user process, it is copied
1815 * and a newline '\n' is added. It is truncated if the buffer is
1818 * Returns 0 on success.
1820 int proc_dostring(struct ctl_table
*table
, int write
,
1821 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1823 if (write
&& *ppos
&& sysctl_writes_strict
== SYSCTL_WRITES_WARN
)
1824 warn_sysctl_write(table
);
1826 return _proc_do_string((char *)(table
->data
), table
->maxlen
, write
,
1827 (char __user
*)buffer
, lenp
, ppos
);
1830 static size_t proc_skip_spaces(char **buf
)
1833 char *tmp
= skip_spaces(*buf
);
1839 static void proc_skip_char(char **buf
, size_t *size
, const char v
)
1849 #define TMPBUFLEN 22
1851 * proc_get_long - reads an ASCII formatted integer from a user buffer
1853 * @buf: a kernel buffer
1854 * @size: size of the kernel buffer
1855 * @val: this is where the number will be stored
1856 * @neg: set to %TRUE if number is negative
1857 * @perm_tr: a vector which contains the allowed trailers
1858 * @perm_tr_len: size of the perm_tr vector
1859 * @tr: pointer to store the trailer character
1861 * In case of success %0 is returned and @buf and @size are updated with
1862 * the amount of bytes read. If @tr is non-NULL and a trailing
1863 * character exists (size is non-zero after returning from this
1864 * function), @tr is updated with the trailing character.
1866 static int proc_get_long(char **buf
, size_t *size
,
1867 unsigned long *val
, bool *neg
,
1868 const char *perm_tr
, unsigned perm_tr_len
, char *tr
)
1871 char *p
, tmp
[TMPBUFLEN
];
1877 if (len
> TMPBUFLEN
- 1)
1878 len
= TMPBUFLEN
- 1;
1880 memcpy(tmp
, *buf
, len
);
1884 if (*p
== '-' && *size
> 1) {
1892 *val
= simple_strtoul(p
, &p
, 0);
1896 /* We don't know if the next char is whitespace thus we may accept
1897 * invalid integers (e.g. 1234...a) or two integers instead of one
1898 * (e.g. 123...1). So lets not allow such large numbers. */
1899 if (len
== TMPBUFLEN
- 1)
1902 if (len
< *size
&& perm_tr_len
&& !memchr(perm_tr
, *p
, perm_tr_len
))
1905 if (tr
&& (len
< *size
))
1915 * proc_put_long - converts an integer to a decimal ASCII formatted string
1917 * @buf: the user buffer
1918 * @size: the size of the user buffer
1919 * @val: the integer to be converted
1920 * @neg: sign of the number, %TRUE for negative
1922 * In case of success %0 is returned and @buf and @size are updated with
1923 * the amount of bytes written.
1925 static int proc_put_long(void __user
**buf
, size_t *size
, unsigned long val
,
1929 char tmp
[TMPBUFLEN
], *p
= tmp
;
1931 sprintf(p
, "%s%lu", neg
? "-" : "", val
);
1935 if (copy_to_user(*buf
, tmp
, len
))
1943 static int proc_put_char(void __user
**buf
, size_t *size
, char c
)
1946 char __user
**buffer
= (char __user
**)buf
;
1947 if (put_user(c
, *buffer
))
1949 (*size
)--, (*buffer
)++;
1955 static int do_proc_dointvec_conv(bool *negp
, unsigned long *lvalp
,
1957 int write
, void *data
)
1960 *valp
= *negp
? -*lvalp
: *lvalp
;
1965 *lvalp
= (unsigned long)-val
;
1968 *lvalp
= (unsigned long)val
;
1974 static const char proc_wspace_sep
[] = { ' ', '\t', '\n' };
1976 static int __do_proc_dointvec(void *tbl_data
, struct ctl_table
*table
,
1977 int write
, void __user
*buffer
,
1978 size_t *lenp
, loff_t
*ppos
,
1979 int (*conv
)(bool *negp
, unsigned long *lvalp
, int *valp
,
1980 int write
, void *data
),
1983 int *i
, vleft
, first
= 1, err
= 0;
1984 unsigned long page
= 0;
1988 if (!tbl_data
|| !table
->maxlen
|| !*lenp
|| (*ppos
&& !write
)) {
1993 i
= (int *) tbl_data
;
1994 vleft
= table
->maxlen
/ sizeof(*i
);
1998 conv
= do_proc_dointvec_conv
;
2002 switch (sysctl_writes_strict
) {
2003 case SYSCTL_WRITES_STRICT
:
2005 case SYSCTL_WRITES_WARN
:
2006 warn_sysctl_write(table
);
2013 if (left
> PAGE_SIZE
- 1)
2014 left
= PAGE_SIZE
- 1;
2015 page
= __get_free_page(GFP_TEMPORARY
);
2016 kbuf
= (char *) page
;
2019 if (copy_from_user(kbuf
, buffer
, left
)) {
2026 for (; left
&& vleft
--; i
++, first
=0) {
2031 left
-= proc_skip_spaces(&kbuf
);
2035 err
= proc_get_long(&kbuf
, &left
, &lval
, &neg
,
2037 sizeof(proc_wspace_sep
), NULL
);
2040 if (conv(&neg
, &lval
, i
, 1, data
)) {
2045 if (conv(&neg
, &lval
, i
, 0, data
)) {
2050 err
= proc_put_char(&buffer
, &left
, '\t');
2053 err
= proc_put_long(&buffer
, &left
, lval
, neg
);
2059 if (!write
&& !first
&& left
&& !err
)
2060 err
= proc_put_char(&buffer
, &left
, '\n');
2061 if (write
&& !err
&& left
)
2062 left
-= proc_skip_spaces(&kbuf
);
2067 return err
? : -EINVAL
;
2075 static int do_proc_dointvec(struct ctl_table
*table
, int write
,
2076 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
2077 int (*conv
)(bool *negp
, unsigned long *lvalp
, int *valp
,
2078 int write
, void *data
),
2081 return __do_proc_dointvec(table
->data
, table
, write
,
2082 buffer
, lenp
, ppos
, conv
, data
);
2086 * proc_dointvec - read a vector of integers
2087 * @table: the sysctl table
2088 * @write: %TRUE if this is a write to the sysctl file
2089 * @buffer: the user buffer
2090 * @lenp: the size of the user buffer
2091 * @ppos: file position
2093 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2094 * values from/to the user buffer, treated as an ASCII string.
2096 * Returns 0 on success.
2098 int proc_dointvec(struct ctl_table
*table
, int write
,
2099 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2101 return do_proc_dointvec(table
,write
,buffer
,lenp
,ppos
,
2106 * Taint values can only be increased
2107 * This means we can safely use a temporary.
2109 static int proc_taint(struct ctl_table
*table
, int write
,
2110 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2113 unsigned long tmptaint
= get_taint();
2116 if (write
&& !capable(CAP_SYS_ADMIN
))
2121 err
= proc_doulongvec_minmax(&t
, write
, buffer
, lenp
, ppos
);
2127 * Poor man's atomic or. Not worth adding a primitive
2128 * to everyone's atomic.h for this
2131 for (i
= 0; i
< BITS_PER_LONG
&& tmptaint
>> i
; i
++) {
2132 if ((tmptaint
>> i
) & 1)
2133 add_taint(i
, LOCKDEP_STILL_OK
);
2140 #ifdef CONFIG_PRINTK
2141 static int proc_dointvec_minmax_sysadmin(struct ctl_table
*table
, int write
,
2142 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2144 if (write
&& !capable(CAP_SYS_ADMIN
))
2147 return proc_dointvec_minmax(table
, write
, buffer
, lenp
, ppos
);
2151 struct do_proc_dointvec_minmax_conv_param
{
2156 static int do_proc_dointvec_minmax_conv(bool *negp
, unsigned long *lvalp
,
2158 int write
, void *data
)
2160 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
2162 int val
= *negp
? -*lvalp
: *lvalp
;
2163 if ((param
->min
&& *param
->min
> val
) ||
2164 (param
->max
&& *param
->max
< val
))
2171 *lvalp
= (unsigned long)-val
;
2174 *lvalp
= (unsigned long)val
;
2181 * proc_dointvec_minmax - read a vector of integers with min/max values
2182 * @table: the sysctl table
2183 * @write: %TRUE if this is a write to the sysctl file
2184 * @buffer: the user buffer
2185 * @lenp: the size of the user buffer
2186 * @ppos: file position
2188 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2189 * values from/to the user buffer, treated as an ASCII string.
2191 * This routine will ensure the values are within the range specified by
2192 * table->extra1 (min) and table->extra2 (max).
2194 * Returns 0 on success.
2196 int proc_dointvec_minmax(struct ctl_table
*table
, int write
,
2197 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2199 struct do_proc_dointvec_minmax_conv_param param
= {
2200 .min
= (int *) table
->extra1
,
2201 .max
= (int *) table
->extra2
,
2203 return do_proc_dointvec(table
, write
, buffer
, lenp
, ppos
,
2204 do_proc_dointvec_minmax_conv
, ¶m
);
2207 static void validate_coredump_safety(void)
2209 #ifdef CONFIG_COREDUMP
2210 if (suid_dumpable
== SUID_DUMP_ROOT
&&
2211 core_pattern
[0] != '/' && core_pattern
[0] != '|') {
2212 printk(KERN_WARNING
"Unsafe core_pattern used with "\
2213 "suid_dumpable=2. Pipe handler or fully qualified "\
2214 "core dump path required.\n");
2219 static int proc_dointvec_minmax_coredump(struct ctl_table
*table
, int write
,
2220 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2222 int error
= proc_dointvec_minmax(table
, write
, buffer
, lenp
, ppos
);
2224 validate_coredump_safety();
2228 #ifdef CONFIG_COREDUMP
2229 static int proc_dostring_coredump(struct ctl_table
*table
, int write
,
2230 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2232 int error
= proc_dostring(table
, write
, buffer
, lenp
, ppos
);
2234 validate_coredump_safety();
2239 static int __do_proc_doulongvec_minmax(void *data
, struct ctl_table
*table
, int write
,
2240 void __user
*buffer
,
2241 size_t *lenp
, loff_t
*ppos
,
2242 unsigned long convmul
,
2243 unsigned long convdiv
)
2245 unsigned long *i
, *min
, *max
;
2246 int vleft
, first
= 1, err
= 0;
2247 unsigned long page
= 0;
2251 if (!data
|| !table
->maxlen
|| !*lenp
|| (*ppos
&& !write
)) {
2256 i
= (unsigned long *) data
;
2257 min
= (unsigned long *) table
->extra1
;
2258 max
= (unsigned long *) table
->extra2
;
2259 vleft
= table
->maxlen
/ sizeof(unsigned long);
2264 switch (sysctl_writes_strict
) {
2265 case SYSCTL_WRITES_STRICT
:
2267 case SYSCTL_WRITES_WARN
:
2268 warn_sysctl_write(table
);
2275 if (left
> PAGE_SIZE
- 1)
2276 left
= PAGE_SIZE
- 1;
2277 page
= __get_free_page(GFP_TEMPORARY
);
2278 kbuf
= (char *) page
;
2281 if (copy_from_user(kbuf
, buffer
, left
)) {
2288 for (; left
&& vleft
--; i
++, first
= 0) {
2294 left
-= proc_skip_spaces(&kbuf
);
2296 err
= proc_get_long(&kbuf
, &left
, &val
, &neg
,
2298 sizeof(proc_wspace_sep
), NULL
);
2303 if ((min
&& val
< *min
) || (max
&& val
> *max
))
2307 val
= convdiv
* (*i
) / convmul
;
2309 err
= proc_put_char(&buffer
, &left
, '\t');
2313 err
= proc_put_long(&buffer
, &left
, val
, false);
2319 if (!write
&& !first
&& left
&& !err
)
2320 err
= proc_put_char(&buffer
, &left
, '\n');
2322 left
-= proc_skip_spaces(&kbuf
);
2327 return err
? : -EINVAL
;
2335 static int do_proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2336 void __user
*buffer
,
2337 size_t *lenp
, loff_t
*ppos
,
2338 unsigned long convmul
,
2339 unsigned long convdiv
)
2341 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2342 buffer
, lenp
, ppos
, convmul
, convdiv
);
2346 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2347 * @table: the sysctl table
2348 * @write: %TRUE if this is a write to the sysctl file
2349 * @buffer: the user buffer
2350 * @lenp: the size of the user buffer
2351 * @ppos: file position
2353 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2354 * values from/to the user buffer, treated as an ASCII string.
2356 * This routine will ensure the values are within the range specified by
2357 * table->extra1 (min) and table->extra2 (max).
2359 * Returns 0 on success.
2361 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2362 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2364 return do_proc_doulongvec_minmax(table
, write
, buffer
, lenp
, ppos
, 1l, 1l);
2368 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2369 * @table: the sysctl table
2370 * @write: %TRUE if this is a write to the sysctl file
2371 * @buffer: the user buffer
2372 * @lenp: the size of the user buffer
2373 * @ppos: file position
2375 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2376 * values from/to the user buffer, treated as an ASCII string. The values
2377 * are treated as milliseconds, and converted to jiffies when they are stored.
2379 * This routine will ensure the values are within the range specified by
2380 * table->extra1 (min) and table->extra2 (max).
2382 * Returns 0 on success.
2384 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2385 void __user
*buffer
,
2386 size_t *lenp
, loff_t
*ppos
)
2388 return do_proc_doulongvec_minmax(table
, write
, buffer
,
2389 lenp
, ppos
, HZ
, 1000l);
2393 static int do_proc_dointvec_jiffies_conv(bool *negp
, unsigned long *lvalp
,
2395 int write
, void *data
)
2398 if (*lvalp
> LONG_MAX
/ HZ
)
2400 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2406 lval
= (unsigned long)-val
;
2409 lval
= (unsigned long)val
;
2416 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp
, unsigned long *lvalp
,
2418 int write
, void *data
)
2421 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2423 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2429 lval
= (unsigned long)-val
;
2432 lval
= (unsigned long)val
;
2434 *lvalp
= jiffies_to_clock_t(lval
);
2439 static int do_proc_dointvec_ms_jiffies_conv(bool *negp
, unsigned long *lvalp
,
2441 int write
, void *data
)
2444 unsigned long jif
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2454 lval
= (unsigned long)-val
;
2457 lval
= (unsigned long)val
;
2459 *lvalp
= jiffies_to_msecs(lval
);
2465 * proc_dointvec_jiffies - read a vector of integers as seconds
2466 * @table: the sysctl table
2467 * @write: %TRUE if this is a write to the sysctl file
2468 * @buffer: the user buffer
2469 * @lenp: the size of the user buffer
2470 * @ppos: file position
2472 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2473 * values from/to the user buffer, treated as an ASCII string.
2474 * The values read are assumed to be in seconds, and are converted into
2477 * Returns 0 on success.
2479 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
,
2480 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2482 return do_proc_dointvec(table
,write
,buffer
,lenp
,ppos
,
2483 do_proc_dointvec_jiffies_conv
,NULL
);
2487 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2488 * @table: the sysctl table
2489 * @write: %TRUE if this is a write to the sysctl file
2490 * @buffer: the user buffer
2491 * @lenp: the size of the user buffer
2492 * @ppos: pointer to the file position
2494 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2495 * values from/to the user buffer, treated as an ASCII string.
2496 * The values read are assumed to be in 1/USER_HZ seconds, and
2497 * are converted into jiffies.
2499 * Returns 0 on success.
2501 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
,
2502 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2504 return do_proc_dointvec(table
,write
,buffer
,lenp
,ppos
,
2505 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2509 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2510 * @table: the sysctl table
2511 * @write: %TRUE if this is a write to the sysctl file
2512 * @buffer: the user buffer
2513 * @lenp: the size of the user buffer
2514 * @ppos: file position
2515 * @ppos: the current position in the file
2517 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2518 * values from/to the user buffer, treated as an ASCII string.
2519 * The values read are assumed to be in 1/1000 seconds, and
2520 * are converted into jiffies.
2522 * Returns 0 on success.
2524 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
,
2525 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2527 return do_proc_dointvec(table
, write
, buffer
, lenp
, ppos
,
2528 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2531 static int proc_do_cad_pid(struct ctl_table
*table
, int write
,
2532 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2534 struct pid
*new_pid
;
2538 tmp
= pid_vnr(cad_pid
);
2540 r
= __do_proc_dointvec(&tmp
, table
, write
, buffer
,
2541 lenp
, ppos
, NULL
, NULL
);
2545 new_pid
= find_get_pid(tmp
);
2549 put_pid(xchg(&cad_pid
, new_pid
));
2554 * proc_do_large_bitmap - read/write from/to a large bitmap
2555 * @table: the sysctl table
2556 * @write: %TRUE if this is a write to the sysctl file
2557 * @buffer: the user buffer
2558 * @lenp: the size of the user buffer
2559 * @ppos: file position
2561 * The bitmap is stored at table->data and the bitmap length (in bits)
2564 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2565 * large bitmaps may be represented in a compact manner. Writing into
2566 * the file will clear the bitmap then update it with the given input.
2568 * Returns 0 on success.
2570 int proc_do_large_bitmap(struct ctl_table
*table
, int write
,
2571 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2575 size_t left
= *lenp
;
2576 unsigned long bitmap_len
= table
->maxlen
;
2577 unsigned long *bitmap
= *(unsigned long **) table
->data
;
2578 unsigned long *tmp_bitmap
= NULL
;
2579 char tr_a
[] = { '-', ',', '\n' }, tr_b
[] = { ',', '\n', 0 }, c
;
2581 if (!bitmap
|| !bitmap_len
|| !left
|| (*ppos
&& !write
)) {
2587 unsigned long page
= 0;
2590 if (left
> PAGE_SIZE
- 1)
2591 left
= PAGE_SIZE
- 1;
2593 page
= __get_free_page(GFP_TEMPORARY
);
2594 kbuf
= (char *) page
;
2597 if (copy_from_user(kbuf
, buffer
, left
)) {
2603 tmp_bitmap
= kzalloc(BITS_TO_LONGS(bitmap_len
) * sizeof(unsigned long),
2609 proc_skip_char(&kbuf
, &left
, '\n');
2610 while (!err
&& left
) {
2611 unsigned long val_a
, val_b
;
2614 err
= proc_get_long(&kbuf
, &left
, &val_a
, &neg
, tr_a
,
2618 if (val_a
>= bitmap_len
|| neg
) {
2630 err
= proc_get_long(&kbuf
, &left
, &val_b
,
2631 &neg
, tr_b
, sizeof(tr_b
),
2635 if (val_b
>= bitmap_len
|| neg
||
2646 bitmap_set(tmp_bitmap
, val_a
, val_b
- val_a
+ 1);
2648 proc_skip_char(&kbuf
, &left
, '\n');
2652 unsigned long bit_a
, bit_b
= 0;
2655 bit_a
= find_next_bit(bitmap
, bitmap_len
, bit_b
);
2656 if (bit_a
>= bitmap_len
)
2658 bit_b
= find_next_zero_bit(bitmap
, bitmap_len
,
2662 err
= proc_put_char(&buffer
, &left
, ',');
2666 err
= proc_put_long(&buffer
, &left
, bit_a
, false);
2669 if (bit_a
!= bit_b
) {
2670 err
= proc_put_char(&buffer
, &left
, '-');
2673 err
= proc_put_long(&buffer
, &left
, bit_b
, false);
2681 err
= proc_put_char(&buffer
, &left
, '\n');
2687 bitmap_or(bitmap
, bitmap
, tmp_bitmap
, bitmap_len
);
2689 bitmap_copy(bitmap
, tmp_bitmap
, bitmap_len
);
2701 #else /* CONFIG_PROC_SYSCTL */
2703 int proc_dostring(struct ctl_table
*table
, int write
,
2704 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2709 int proc_dointvec(struct ctl_table
*table
, int write
,
2710 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2715 int proc_dointvec_minmax(struct ctl_table
*table
, int write
,
2716 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2721 int proc_dointvec_jiffies(struct ctl_table
*table
, int write
,
2722 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2727 int proc_dointvec_userhz_jiffies(struct ctl_table
*table
, int write
,
2728 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2733 int proc_dointvec_ms_jiffies(struct ctl_table
*table
, int write
,
2734 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2739 int proc_doulongvec_minmax(struct ctl_table
*table
, int write
,
2740 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2745 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table
*table
, int write
,
2746 void __user
*buffer
,
2747 size_t *lenp
, loff_t
*ppos
)
2753 #endif /* CONFIG_PROC_SYSCTL */
2756 * No sense putting this after each symbol definition, twice,
2757 * exception granted :-)
2759 EXPORT_SYMBOL(proc_dointvec
);
2760 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2761 EXPORT_SYMBOL(proc_dointvec_minmax
);
2762 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2763 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2764 EXPORT_SYMBOL(proc_dostring
);
2765 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2766 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);