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>
66 #include <asm/uaccess.h>
67 #include <asm/processor.h>
71 #include <asm/stacktrace.h>
75 #include <asm/setup.h>
77 #ifdef CONFIG_BSD_PROCESS_ACCT
78 #include <linux/acct.h>
80 #ifdef CONFIG_RT_MUTEXES
81 #include <linux/rtmutex.h>
83 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
84 #include <linux/lockdep.h>
86 #ifdef CONFIG_CHR_DEV_SG
90 #ifdef CONFIG_LOCKUP_DETECTOR
91 #include <linux/nmi.h>
95 #if defined(CONFIG_SYSCTL)
97 /* External variables not in a header file. */
98 extern int sysctl_overcommit_memory;
99 extern int sysctl_overcommit_ratio;
100 extern int max_threads;
101 extern int suid_dumpable;
102 #ifdef CONFIG_COREDUMP
103 extern int core_uses_pid;
104 extern char core_pattern[];
105 extern unsigned int core_pipe_limit;
108 extern int extra_free_kbytes;
109 extern int min_free_order_shift;
110 extern int pid_max_min, pid_max_max;
111 extern int percpu_pagelist_fraction;
112 extern int compat_log;
113 extern int latencytop_enabled;
114 extern int sysctl_nr_open_min, sysctl_nr_open_max;
116 extern int sysctl_nr_trim_pages;
119 extern int blk_iopoll_enabled;
122 /* Constants used for minimum and maximum */
123 #ifdef CONFIG_LOCKUP_DETECTOR
124 static int sixty = 60;
125 static int neg_one = -1;
129 static int __maybe_unused one = 1;
130 static int __maybe_unused two = 2;
131 static int __maybe_unused three = 3;
132 static unsigned long one_ul = 1;
133 static int one_hundred = 100;
135 static int ten_thousand = 10000;
138 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
139 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
141 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
142 static int maxolduid = 65535;
143 static int minolduid;
144 static int min_percpu_pagelist_fract = 8;
146 static int ngroups_max = NGROUPS_MAX;
147 static const int cap_last_cap = CAP_LAST_CAP;
149 #ifdef CONFIG_INOTIFY_USER
150 #include <linux/inotify.h>
155 #ifdef CONFIG_SPARC64
156 extern int sysctl_tsb_ratio;
160 extern int pwrsw_enabled;
163 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
164 extern int unaligned_enabled;
168 extern int unaligned_dump_stack;
171 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
172 extern int no_unaligned_warning;
175 #ifdef CONFIG_PROC_SYSCTL
176 static int proc_do_cad_pid(struct ctl_table *table, int write,
177 void __user *buffer, size_t *lenp, loff_t *ppos);
178 static int proc_taint(struct ctl_table *table, int write,
179 void __user *buffer, size_t *lenp, loff_t *ppos);
183 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
184 void __user *buffer, size_t *lenp, loff_t *ppos);
187 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
188 void __user *buffer, size_t *lenp, loff_t *ppos);
189 #ifdef CONFIG_COREDUMP
190 static int proc_dostring_coredump(struct ctl_table *table, int write,
191 void __user *buffer, size_t *lenp, loff_t *ppos);
194 #ifdef CONFIG_MAGIC_SYSRQ
195 /* Note: sysrq code uses it's own private copy */
196 static int __sysrq_enabled = SYSRQ_DEFAULT_ENABLE;
198 static int sysrq_sysctl_handler(ctl_table *table, int write,
199 void __user *buffer, size_t *lenp,
204 error = proc_dointvec(table, write, buffer, lenp, ppos);
209 sysrq_toggle_support(__sysrq_enabled);
216 static struct ctl_table kern_table[];
217 static struct ctl_table vm_table[];
218 static struct ctl_table fs_table[];
219 static struct ctl_table debug_table[];
220 static struct ctl_table dev_table[];
221 extern struct ctl_table random_table[];
223 extern struct ctl_table epoll_table[];
226 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
227 int sysctl_legacy_va_layout;
230 /* The default sysctl tables: */
232 static struct ctl_table sysctl_base_table[] = {
234 .procname = "kernel",
251 .child = debug_table,
261 #ifdef CONFIG_SCHED_DEBUG
262 static int min_sched_granularity_ns = 100000; /* 100 usecs */
263 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
264 static int min_wakeup_granularity_ns; /* 0 usecs */
265 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
267 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
268 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
269 #endif /* CONFIG_SMP */
270 #endif /* CONFIG_SCHED_DEBUG */
272 #ifdef CONFIG_COMPACTION
273 static int min_extfrag_threshold;
274 static int max_extfrag_threshold = 1000;
277 static struct ctl_table kern_table[] = {
279 .procname = "sched_child_runs_first",
280 .data = &sysctl_sched_child_runs_first,
281 .maxlen = sizeof(unsigned int),
283 .proc_handler = proc_dointvec,
285 #ifdef CONFIG_SCHED_DEBUG
287 .procname = "sched_min_granularity_ns",
288 .data = &sysctl_sched_min_granularity,
289 .maxlen = sizeof(unsigned int),
291 .proc_handler = sched_proc_update_handler,
292 .extra1 = &min_sched_granularity_ns,
293 .extra2 = &max_sched_granularity_ns,
296 .procname = "sched_latency_ns",
297 .data = &sysctl_sched_latency,
298 .maxlen = sizeof(unsigned int),
300 .proc_handler = sched_proc_update_handler,
301 .extra1 = &min_sched_granularity_ns,
302 .extra2 = &max_sched_granularity_ns,
305 .procname = "sched_wakeup_granularity_ns",
306 .data = &sysctl_sched_wakeup_granularity,
307 .maxlen = sizeof(unsigned int),
309 .proc_handler = sched_proc_update_handler,
310 .extra1 = &min_wakeup_granularity_ns,
311 .extra2 = &max_wakeup_granularity_ns,
315 .procname = "sched_tunable_scaling",
316 .data = &sysctl_sched_tunable_scaling,
317 .maxlen = sizeof(enum sched_tunable_scaling),
319 .proc_handler = sched_proc_update_handler,
320 .extra1 = &min_sched_tunable_scaling,
321 .extra2 = &max_sched_tunable_scaling,
324 .procname = "sched_migration_cost_ns",
325 .data = &sysctl_sched_migration_cost,
326 .maxlen = sizeof(unsigned int),
328 .proc_handler = proc_dointvec,
331 .procname = "sched_nr_migrate",
332 .data = &sysctl_sched_nr_migrate,
333 .maxlen = sizeof(unsigned int),
335 .proc_handler = proc_dointvec,
338 .procname = "sched_time_avg_ms",
339 .data = &sysctl_sched_time_avg,
340 .maxlen = sizeof(unsigned int),
342 .proc_handler = proc_dointvec,
345 .procname = "sched_shares_window_ns",
346 .data = &sysctl_sched_shares_window,
347 .maxlen = sizeof(unsigned int),
349 .proc_handler = proc_dointvec,
352 .procname = "timer_migration",
353 .data = &sysctl_timer_migration,
354 .maxlen = sizeof(unsigned int),
356 .proc_handler = proc_dointvec_minmax,
360 #endif /* CONFIG_SMP */
361 #ifdef CONFIG_NUMA_BALANCING
363 .procname = "numa_balancing_scan_delay_ms",
364 .data = &sysctl_numa_balancing_scan_delay,
365 .maxlen = sizeof(unsigned int),
367 .proc_handler = proc_dointvec,
370 .procname = "numa_balancing_scan_period_min_ms",
371 .data = &sysctl_numa_balancing_scan_period_min,
372 .maxlen = sizeof(unsigned int),
374 .proc_handler = proc_dointvec,
377 .procname = "numa_balancing_scan_period_reset",
378 .data = &sysctl_numa_balancing_scan_period_reset,
379 .maxlen = sizeof(unsigned int),
381 .proc_handler = proc_dointvec,
384 .procname = "numa_balancing_scan_period_max_ms",
385 .data = &sysctl_numa_balancing_scan_period_max,
386 .maxlen = sizeof(unsigned int),
388 .proc_handler = proc_dointvec,
391 .procname = "numa_balancing_scan_size_mb",
392 .data = &sysctl_numa_balancing_scan_size,
393 .maxlen = sizeof(unsigned int),
395 .proc_handler = proc_dointvec,
397 #endif /* CONFIG_NUMA_BALANCING */
398 #endif /* CONFIG_SCHED_DEBUG */
400 .procname = "sched_rt_period_us",
401 .data = &sysctl_sched_rt_period,
402 .maxlen = sizeof(unsigned int),
404 .proc_handler = sched_rt_handler,
407 .procname = "sched_rt_runtime_us",
408 .data = &sysctl_sched_rt_runtime,
409 .maxlen = sizeof(int),
411 .proc_handler = sched_rt_handler,
414 .procname = "sched_rr_timeslice_ms",
415 .data = &sched_rr_timeslice,
416 .maxlen = sizeof(int),
418 .proc_handler = sched_rr_handler,
420 #ifdef CONFIG_SCHED_AUTOGROUP
422 .procname = "sched_autogroup_enabled",
423 .data = &sysctl_sched_autogroup_enabled,
424 .maxlen = sizeof(unsigned int),
426 .proc_handler = proc_dointvec_minmax,
431 #ifdef CONFIG_CFS_BANDWIDTH
433 .procname = "sched_cfs_bandwidth_slice_us",
434 .data = &sysctl_sched_cfs_bandwidth_slice,
435 .maxlen = sizeof(unsigned int),
437 .proc_handler = proc_dointvec_minmax,
441 #ifdef CONFIG_PROVE_LOCKING
443 .procname = "prove_locking",
444 .data = &prove_locking,
445 .maxlen = sizeof(int),
447 .proc_handler = proc_dointvec,
450 #ifdef CONFIG_LOCK_STAT
452 .procname = "lock_stat",
454 .maxlen = sizeof(int),
456 .proc_handler = proc_dointvec,
461 .data = &panic_timeout,
462 .maxlen = sizeof(int),
464 .proc_handler = proc_dointvec,
466 #ifdef CONFIG_COREDUMP
468 .procname = "core_uses_pid",
469 .data = &core_uses_pid,
470 .maxlen = sizeof(int),
472 .proc_handler = proc_dointvec,
475 .procname = "core_pattern",
476 .data = core_pattern,
477 .maxlen = CORENAME_MAX_SIZE,
479 .proc_handler = proc_dostring_coredump,
482 .procname = "core_pipe_limit",
483 .data = &core_pipe_limit,
484 .maxlen = sizeof(unsigned int),
486 .proc_handler = proc_dointvec,
489 #ifdef CONFIG_PROC_SYSCTL
491 .procname = "tainted",
492 .maxlen = sizeof(long),
494 .proc_handler = proc_taint,
497 #ifdef CONFIG_LATENCYTOP
499 .procname = "latencytop",
500 .data = &latencytop_enabled,
501 .maxlen = sizeof(int),
503 .proc_handler = proc_dointvec,
506 #ifdef CONFIG_BLK_DEV_INITRD
508 .procname = "real-root-dev",
509 .data = &real_root_dev,
510 .maxlen = sizeof(int),
512 .proc_handler = proc_dointvec,
516 .procname = "print-fatal-signals",
517 .data = &print_fatal_signals,
518 .maxlen = sizeof(int),
520 .proc_handler = proc_dointvec,
524 .procname = "reboot-cmd",
525 .data = reboot_command,
528 .proc_handler = proc_dostring,
531 .procname = "stop-a",
532 .data = &stop_a_enabled,
533 .maxlen = sizeof (int),
535 .proc_handler = proc_dointvec,
538 .procname = "scons-poweroff",
539 .data = &scons_pwroff,
540 .maxlen = sizeof (int),
542 .proc_handler = proc_dointvec,
545 #ifdef CONFIG_SPARC64
547 .procname = "tsb-ratio",
548 .data = &sysctl_tsb_ratio,
549 .maxlen = sizeof (int),
551 .proc_handler = proc_dointvec,
556 .procname = "soft-power",
557 .data = &pwrsw_enabled,
558 .maxlen = sizeof (int),
560 .proc_handler = proc_dointvec,
563 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
565 .procname = "unaligned-trap",
566 .data = &unaligned_enabled,
567 .maxlen = sizeof (int),
569 .proc_handler = proc_dointvec,
573 .procname = "ctrl-alt-del",
575 .maxlen = sizeof(int),
577 .proc_handler = proc_dointvec,
579 #ifdef CONFIG_FUNCTION_TRACER
581 .procname = "ftrace_enabled",
582 .data = &ftrace_enabled,
583 .maxlen = sizeof(int),
585 .proc_handler = ftrace_enable_sysctl,
588 #ifdef CONFIG_STACK_TRACER
590 .procname = "stack_tracer_enabled",
591 .data = &stack_tracer_enabled,
592 .maxlen = sizeof(int),
594 .proc_handler = stack_trace_sysctl,
597 #ifdef CONFIG_TRACING
599 .procname = "ftrace_dump_on_oops",
600 .data = &ftrace_dump_on_oops,
601 .maxlen = sizeof(int),
603 .proc_handler = proc_dointvec,
606 #ifdef CONFIG_MODULES
608 .procname = "modprobe",
609 .data = &modprobe_path,
610 .maxlen = KMOD_PATH_LEN,
612 .proc_handler = proc_dostring,
615 .procname = "modules_disabled",
616 .data = &modules_disabled,
617 .maxlen = sizeof(int),
619 /* only handle a transition from default "0" to "1" */
620 .proc_handler = proc_dointvec_minmax,
627 .procname = "hotplug",
628 .data = &uevent_helper,
629 .maxlen = UEVENT_HELPER_PATH_LEN,
631 .proc_handler = proc_dostring,
634 #ifdef CONFIG_CHR_DEV_SG
636 .procname = "sg-big-buff",
637 .data = &sg_big_buff,
638 .maxlen = sizeof (int),
640 .proc_handler = proc_dointvec,
643 #ifdef CONFIG_BSD_PROCESS_ACCT
647 .maxlen = 3*sizeof(int),
649 .proc_handler = proc_dointvec,
652 #ifdef CONFIG_MAGIC_SYSRQ
655 .data = &__sysrq_enabled,
656 .maxlen = sizeof (int),
658 .proc_handler = sysrq_sysctl_handler,
661 #ifdef CONFIG_PROC_SYSCTL
663 .procname = "cad_pid",
665 .maxlen = sizeof (int),
667 .proc_handler = proc_do_cad_pid,
671 .procname = "threads-max",
672 .data = &max_threads,
673 .maxlen = sizeof(int),
675 .proc_handler = proc_dointvec,
678 .procname = "random",
680 .child = random_table,
683 .procname = "usermodehelper",
685 .child = usermodehelper_table,
688 .procname = "overflowuid",
689 .data = &overflowuid,
690 .maxlen = sizeof(int),
692 .proc_handler = proc_dointvec_minmax,
693 .extra1 = &minolduid,
694 .extra2 = &maxolduid,
697 .procname = "overflowgid",
698 .data = &overflowgid,
699 .maxlen = sizeof(int),
701 .proc_handler = proc_dointvec_minmax,
702 .extra1 = &minolduid,
703 .extra2 = &maxolduid,
706 #ifdef CONFIG_MATHEMU
708 .procname = "ieee_emulation_warnings",
709 .data = &sysctl_ieee_emulation_warnings,
710 .maxlen = sizeof(int),
712 .proc_handler = proc_dointvec,
716 .procname = "userprocess_debug",
717 .data = &show_unhandled_signals,
718 .maxlen = sizeof(int),
720 .proc_handler = proc_dointvec,
724 .procname = "pid_max",
726 .maxlen = sizeof (int),
728 .proc_handler = proc_dointvec_minmax,
729 .extra1 = &pid_max_min,
730 .extra2 = &pid_max_max,
733 .procname = "panic_on_oops",
734 .data = &panic_on_oops,
735 .maxlen = sizeof(int),
737 .proc_handler = proc_dointvec,
739 #if defined CONFIG_PRINTK
741 .procname = "printk",
742 .data = &console_loglevel,
743 .maxlen = 4*sizeof(int),
745 .proc_handler = proc_dointvec,
748 .procname = "printk_ratelimit",
749 .data = &printk_ratelimit_state.interval,
750 .maxlen = sizeof(int),
752 .proc_handler = proc_dointvec_jiffies,
755 .procname = "printk_ratelimit_burst",
756 .data = &printk_ratelimit_state.burst,
757 .maxlen = sizeof(int),
759 .proc_handler = proc_dointvec,
762 .procname = "printk_delay",
763 .data = &printk_delay_msec,
764 .maxlen = sizeof(int),
766 .proc_handler = proc_dointvec_minmax,
768 .extra2 = &ten_thousand,
771 .procname = "dmesg_restrict",
772 .data = &dmesg_restrict,
773 .maxlen = sizeof(int),
775 .proc_handler = proc_dointvec_minmax_sysadmin,
780 .procname = "kptr_restrict",
781 .data = &kptr_restrict,
782 .maxlen = sizeof(int),
784 .proc_handler = proc_dointvec_minmax_sysadmin,
790 .procname = "ngroups_max",
791 .data = &ngroups_max,
792 .maxlen = sizeof (int),
794 .proc_handler = proc_dointvec,
797 .procname = "cap_last_cap",
798 .data = (void *)&cap_last_cap,
799 .maxlen = sizeof(int),
801 .proc_handler = proc_dointvec,
803 #if defined(CONFIG_LOCKUP_DETECTOR)
805 .procname = "watchdog",
806 .data = &watchdog_enabled,
807 .maxlen = sizeof (int),
809 .proc_handler = proc_dowatchdog,
814 .procname = "watchdog_thresh",
815 .data = &watchdog_thresh,
816 .maxlen = sizeof(int),
818 .proc_handler = proc_dowatchdog,
823 .procname = "softlockup_panic",
824 .data = &softlockup_panic,
825 .maxlen = sizeof(int),
827 .proc_handler = proc_dointvec_minmax,
832 .procname = "nmi_watchdog",
833 .data = &watchdog_enabled,
834 .maxlen = sizeof (int),
836 .proc_handler = proc_dowatchdog,
841 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
843 .procname = "unknown_nmi_panic",
844 .data = &unknown_nmi_panic,
845 .maxlen = sizeof (int),
847 .proc_handler = proc_dointvec,
850 #if defined(CONFIG_X86)
852 .procname = "panic_on_unrecovered_nmi",
853 .data = &panic_on_unrecovered_nmi,
854 .maxlen = sizeof(int),
856 .proc_handler = proc_dointvec,
859 .procname = "panic_on_io_nmi",
860 .data = &panic_on_io_nmi,
861 .maxlen = sizeof(int),
863 .proc_handler = proc_dointvec,
865 #ifdef CONFIG_DEBUG_STACKOVERFLOW
867 .procname = "panic_on_stackoverflow",
868 .data = &sysctl_panic_on_stackoverflow,
869 .maxlen = sizeof(int),
871 .proc_handler = proc_dointvec,
875 .procname = "bootloader_type",
876 .data = &bootloader_type,
877 .maxlen = sizeof (int),
879 .proc_handler = proc_dointvec,
882 .procname = "bootloader_version",
883 .data = &bootloader_version,
884 .maxlen = sizeof (int),
886 .proc_handler = proc_dointvec,
889 .procname = "kstack_depth_to_print",
890 .data = &kstack_depth_to_print,
891 .maxlen = sizeof(int),
893 .proc_handler = proc_dointvec,
896 .procname = "io_delay_type",
897 .data = &io_delay_type,
898 .maxlen = sizeof(int),
900 .proc_handler = proc_dointvec,
903 #if defined(CONFIG_MMU)
905 .procname = "randomize_va_space",
906 .data = &randomize_va_space,
907 .maxlen = sizeof(int),
909 .proc_handler = proc_dointvec,
912 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
914 .procname = "spin_retry",
916 .maxlen = sizeof (int),
918 .proc_handler = proc_dointvec,
921 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
923 .procname = "acpi_video_flags",
924 .data = &acpi_realmode_flags,
925 .maxlen = sizeof (unsigned long),
927 .proc_handler = proc_doulongvec_minmax,
930 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
932 .procname = "ignore-unaligned-usertrap",
933 .data = &no_unaligned_warning,
934 .maxlen = sizeof (int),
936 .proc_handler = proc_dointvec,
941 .procname = "unaligned-dump-stack",
942 .data = &unaligned_dump_stack,
943 .maxlen = sizeof (int),
945 .proc_handler = proc_dointvec,
948 #ifdef CONFIG_DETECT_HUNG_TASK
950 .procname = "hung_task_panic",
951 .data = &sysctl_hung_task_panic,
952 .maxlen = sizeof(int),
954 .proc_handler = proc_dointvec_minmax,
959 .procname = "hung_task_check_count",
960 .data = &sysctl_hung_task_check_count,
961 .maxlen = sizeof(unsigned long),
963 .proc_handler = proc_doulongvec_minmax,
966 .procname = "hung_task_timeout_secs",
967 .data = &sysctl_hung_task_timeout_secs,
968 .maxlen = sizeof(unsigned long),
970 .proc_handler = proc_dohung_task_timeout_secs,
973 .procname = "hung_task_warnings",
974 .data = &sysctl_hung_task_warnings,
975 .maxlen = sizeof(unsigned long),
977 .proc_handler = proc_doulongvec_minmax,
982 .procname = "compat-log",
984 .maxlen = sizeof (int),
986 .proc_handler = proc_dointvec,
989 #ifdef CONFIG_RT_MUTEXES
991 .procname = "max_lock_depth",
992 .data = &max_lock_depth,
993 .maxlen = sizeof(int),
995 .proc_handler = proc_dointvec,
999 .procname = "poweroff_cmd",
1000 .data = &poweroff_cmd,
1001 .maxlen = POWEROFF_CMD_PATH_LEN,
1003 .proc_handler = proc_dostring,
1009 .child = key_sysctls,
1012 #ifdef CONFIG_RCU_TORTURE_TEST
1014 .procname = "rcutorture_runnable",
1015 .data = &rcutorture_runnable,
1016 .maxlen = sizeof(int),
1018 .proc_handler = proc_dointvec,
1021 #ifdef CONFIG_PERF_EVENTS
1023 * User-space scripts rely on the existence of this file
1024 * as a feature check for perf_events being enabled.
1026 * So it's an ABI, do not remove!
1029 .procname = "perf_event_paranoid",
1030 .data = &sysctl_perf_event_paranoid,
1031 .maxlen = sizeof(sysctl_perf_event_paranoid),
1033 .proc_handler = proc_dointvec,
1036 .procname = "perf_event_mlock_kb",
1037 .data = &sysctl_perf_event_mlock,
1038 .maxlen = sizeof(sysctl_perf_event_mlock),
1040 .proc_handler = proc_dointvec,
1043 .procname = "perf_event_max_sample_rate",
1044 .data = &sysctl_perf_event_sample_rate,
1045 .maxlen = sizeof(sysctl_perf_event_sample_rate),
1047 .proc_handler = perf_proc_update_handler,
1050 #ifdef CONFIG_KMEMCHECK
1052 .procname = "kmemcheck",
1053 .data = &kmemcheck_enabled,
1054 .maxlen = sizeof(int),
1056 .proc_handler = proc_dointvec,
1061 .procname = "blk_iopoll",
1062 .data = &blk_iopoll_enabled,
1063 .maxlen = sizeof(int),
1065 .proc_handler = proc_dointvec,
1071 static struct ctl_table vm_table[] = {
1073 .procname = "overcommit_memory",
1074 .data = &sysctl_overcommit_memory,
1075 .maxlen = sizeof(sysctl_overcommit_memory),
1077 .proc_handler = proc_dointvec_minmax,
1082 .procname = "panic_on_oom",
1083 .data = &sysctl_panic_on_oom,
1084 .maxlen = sizeof(sysctl_panic_on_oom),
1086 .proc_handler = proc_dointvec_minmax,
1091 .procname = "oom_kill_allocating_task",
1092 .data = &sysctl_oom_kill_allocating_task,
1093 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1095 .proc_handler = proc_dointvec,
1098 .procname = "oom_dump_tasks",
1099 .data = &sysctl_oom_dump_tasks,
1100 .maxlen = sizeof(sysctl_oom_dump_tasks),
1102 .proc_handler = proc_dointvec,
1105 .procname = "overcommit_ratio",
1106 .data = &sysctl_overcommit_ratio,
1107 .maxlen = sizeof(sysctl_overcommit_ratio),
1109 .proc_handler = proc_dointvec,
1112 .procname = "page-cluster",
1113 .data = &page_cluster,
1114 .maxlen = sizeof(int),
1116 .proc_handler = proc_dointvec_minmax,
1120 .procname = "dirty_background_ratio",
1121 .data = &dirty_background_ratio,
1122 .maxlen = sizeof(dirty_background_ratio),
1124 .proc_handler = dirty_background_ratio_handler,
1126 .extra2 = &one_hundred,
1129 .procname = "dirty_background_bytes",
1130 .data = &dirty_background_bytes,
1131 .maxlen = sizeof(dirty_background_bytes),
1133 .proc_handler = dirty_background_bytes_handler,
1137 .procname = "dirty_ratio",
1138 .data = &vm_dirty_ratio,
1139 .maxlen = sizeof(vm_dirty_ratio),
1141 .proc_handler = dirty_ratio_handler,
1143 .extra2 = &one_hundred,
1146 .procname = "dirty_bytes",
1147 .data = &vm_dirty_bytes,
1148 .maxlen = sizeof(vm_dirty_bytes),
1150 .proc_handler = dirty_bytes_handler,
1151 .extra1 = &dirty_bytes_min,
1154 .procname = "dirty_writeback_centisecs",
1155 .data = &dirty_writeback_interval,
1156 .maxlen = sizeof(dirty_writeback_interval),
1158 .proc_handler = dirty_writeback_centisecs_handler,
1161 .procname = "dirty_expire_centisecs",
1162 .data = &dirty_expire_interval,
1163 .maxlen = sizeof(dirty_expire_interval),
1165 .proc_handler = proc_dointvec_minmax,
1169 .procname = "nr_pdflush_threads",
1170 .mode = 0444 /* read-only */,
1171 .proc_handler = pdflush_proc_obsolete,
1174 .procname = "swappiness",
1175 .data = &vm_swappiness,
1176 .maxlen = sizeof(vm_swappiness),
1178 .proc_handler = proc_dointvec_minmax,
1180 .extra2 = &one_hundred,
1182 #ifdef CONFIG_HUGETLB_PAGE
1184 .procname = "nr_hugepages",
1186 .maxlen = sizeof(unsigned long),
1188 .proc_handler = hugetlb_sysctl_handler,
1189 .extra1 = (void *)&hugetlb_zero,
1190 .extra2 = (void *)&hugetlb_infinity,
1194 .procname = "nr_hugepages_mempolicy",
1196 .maxlen = sizeof(unsigned long),
1198 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1199 .extra1 = (void *)&hugetlb_zero,
1200 .extra2 = (void *)&hugetlb_infinity,
1204 .procname = "hugetlb_shm_group",
1205 .data = &sysctl_hugetlb_shm_group,
1206 .maxlen = sizeof(gid_t),
1208 .proc_handler = proc_dointvec,
1211 .procname = "hugepages_treat_as_movable",
1212 .data = &hugepages_treat_as_movable,
1213 .maxlen = sizeof(int),
1215 .proc_handler = hugetlb_treat_movable_handler,
1218 .procname = "nr_overcommit_hugepages",
1220 .maxlen = sizeof(unsigned long),
1222 .proc_handler = hugetlb_overcommit_handler,
1223 .extra1 = (void *)&hugetlb_zero,
1224 .extra2 = (void *)&hugetlb_infinity,
1228 .procname = "lowmem_reserve_ratio",
1229 .data = &sysctl_lowmem_reserve_ratio,
1230 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1232 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1235 .procname = "drop_caches",
1236 .data = &sysctl_drop_caches,
1237 .maxlen = sizeof(int),
1239 .proc_handler = drop_caches_sysctl_handler,
1243 #ifdef CONFIG_COMPACTION
1245 .procname = "compact_memory",
1246 .data = &sysctl_compact_memory,
1247 .maxlen = sizeof(int),
1249 .proc_handler = sysctl_compaction_handler,
1252 .procname = "extfrag_threshold",
1253 .data = &sysctl_extfrag_threshold,
1254 .maxlen = sizeof(int),
1256 .proc_handler = sysctl_extfrag_handler,
1257 .extra1 = &min_extfrag_threshold,
1258 .extra2 = &max_extfrag_threshold,
1261 #endif /* CONFIG_COMPACTION */
1263 .procname = "min_free_kbytes",
1264 .data = &min_free_kbytes,
1265 .maxlen = sizeof(min_free_kbytes),
1267 .proc_handler = min_free_kbytes_sysctl_handler,
1271 .procname = "extra_free_kbytes",
1272 .data = &extra_free_kbytes,
1273 .maxlen = sizeof(extra_free_kbytes),
1275 .proc_handler = min_free_kbytes_sysctl_handler,
1279 .procname = "min_free_order_shift",
1280 .data = &min_free_order_shift,
1281 .maxlen = sizeof(min_free_order_shift),
1283 .proc_handler = &proc_dointvec
1286 .procname = "percpu_pagelist_fraction",
1287 .data = &percpu_pagelist_fraction,
1288 .maxlen = sizeof(percpu_pagelist_fraction),
1290 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1291 .extra1 = &min_percpu_pagelist_fract,
1295 .procname = "max_map_count",
1296 .data = &sysctl_max_map_count,
1297 .maxlen = sizeof(sysctl_max_map_count),
1299 .proc_handler = proc_dointvec_minmax,
1304 .procname = "nr_trim_pages",
1305 .data = &sysctl_nr_trim_pages,
1306 .maxlen = sizeof(sysctl_nr_trim_pages),
1308 .proc_handler = proc_dointvec_minmax,
1313 .procname = "laptop_mode",
1314 .data = &laptop_mode,
1315 .maxlen = sizeof(laptop_mode),
1317 .proc_handler = proc_dointvec_jiffies,
1320 .procname = "block_dump",
1321 .data = &block_dump,
1322 .maxlen = sizeof(block_dump),
1324 .proc_handler = proc_dointvec,
1328 .procname = "vfs_cache_pressure",
1329 .data = &sysctl_vfs_cache_pressure,
1330 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1332 .proc_handler = proc_dointvec,
1335 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1337 .procname = "legacy_va_layout",
1338 .data = &sysctl_legacy_va_layout,
1339 .maxlen = sizeof(sysctl_legacy_va_layout),
1341 .proc_handler = proc_dointvec,
1347 .procname = "zone_reclaim_mode",
1348 .data = &zone_reclaim_mode,
1349 .maxlen = sizeof(zone_reclaim_mode),
1351 .proc_handler = proc_dointvec,
1355 .procname = "min_unmapped_ratio",
1356 .data = &sysctl_min_unmapped_ratio,
1357 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1359 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1361 .extra2 = &one_hundred,
1364 .procname = "min_slab_ratio",
1365 .data = &sysctl_min_slab_ratio,
1366 .maxlen = sizeof(sysctl_min_slab_ratio),
1368 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1370 .extra2 = &one_hundred,
1375 .procname = "stat_interval",
1376 .data = &sysctl_stat_interval,
1377 .maxlen = sizeof(sysctl_stat_interval),
1379 .proc_handler = proc_dointvec_jiffies,
1384 .procname = "mmap_min_addr",
1385 .data = &dac_mmap_min_addr,
1386 .maxlen = sizeof(unsigned long),
1388 .proc_handler = mmap_min_addr_handler,
1393 .procname = "numa_zonelist_order",
1394 .data = &numa_zonelist_order,
1395 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1397 .proc_handler = numa_zonelist_order_handler,
1400 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1401 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1403 .procname = "vdso_enabled",
1404 .data = &vdso_enabled,
1405 .maxlen = sizeof(vdso_enabled),
1407 .proc_handler = proc_dointvec,
1411 #ifdef CONFIG_HIGHMEM
1413 .procname = "highmem_is_dirtyable",
1414 .data = &vm_highmem_is_dirtyable,
1415 .maxlen = sizeof(vm_highmem_is_dirtyable),
1417 .proc_handler = proc_dointvec_minmax,
1423 .procname = "scan_unevictable_pages",
1424 .data = &scan_unevictable_pages,
1425 .maxlen = sizeof(scan_unevictable_pages),
1427 .proc_handler = scan_unevictable_handler,
1429 #ifdef CONFIG_MEMORY_FAILURE
1431 .procname = "memory_failure_early_kill",
1432 .data = &sysctl_memory_failure_early_kill,
1433 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1435 .proc_handler = proc_dointvec_minmax,
1440 .procname = "memory_failure_recovery",
1441 .data = &sysctl_memory_failure_recovery,
1442 .maxlen = sizeof(sysctl_memory_failure_recovery),
1444 .proc_handler = proc_dointvec_minmax,
1450 .procname = "user_reserve_kbytes",
1451 .data = &sysctl_user_reserve_kbytes,
1452 .maxlen = sizeof(sysctl_user_reserve_kbytes),
1454 .proc_handler = proc_doulongvec_minmax,
1457 .procname = "admin_reserve_kbytes",
1458 .data = &sysctl_admin_reserve_kbytes,
1459 .maxlen = sizeof(sysctl_admin_reserve_kbytes),
1461 .proc_handler = proc_doulongvec_minmax,
1466 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1467 static struct ctl_table binfmt_misc_table[] = {
1472 static struct ctl_table fs_table[] = {
1474 .procname = "inode-nr",
1475 .data = &inodes_stat,
1476 .maxlen = 2*sizeof(int),
1478 .proc_handler = proc_nr_inodes,
1481 .procname = "inode-state",
1482 .data = &inodes_stat,
1483 .maxlen = 7*sizeof(int),
1485 .proc_handler = proc_nr_inodes,
1488 .procname = "file-nr",
1489 .data = &files_stat,
1490 .maxlen = sizeof(files_stat),
1492 .proc_handler = proc_nr_files,
1495 .procname = "file-max",
1496 .data = &files_stat.max_files,
1497 .maxlen = sizeof(files_stat.max_files),
1499 .proc_handler = proc_doulongvec_minmax,
1502 .procname = "nr_open",
1503 .data = &sysctl_nr_open,
1504 .maxlen = sizeof(int),
1506 .proc_handler = proc_dointvec_minmax,
1507 .extra1 = &sysctl_nr_open_min,
1508 .extra2 = &sysctl_nr_open_max,
1511 .procname = "dentry-state",
1512 .data = &dentry_stat,
1513 .maxlen = 6*sizeof(int),
1515 .proc_handler = proc_nr_dentry,
1518 .procname = "overflowuid",
1519 .data = &fs_overflowuid,
1520 .maxlen = sizeof(int),
1522 .proc_handler = proc_dointvec_minmax,
1523 .extra1 = &minolduid,
1524 .extra2 = &maxolduid,
1527 .procname = "overflowgid",
1528 .data = &fs_overflowgid,
1529 .maxlen = sizeof(int),
1531 .proc_handler = proc_dointvec_minmax,
1532 .extra1 = &minolduid,
1533 .extra2 = &maxolduid,
1535 #ifdef CONFIG_FILE_LOCKING
1537 .procname = "leases-enable",
1538 .data = &leases_enable,
1539 .maxlen = sizeof(int),
1541 .proc_handler = proc_dointvec,
1544 #ifdef CONFIG_DNOTIFY
1546 .procname = "dir-notify-enable",
1547 .data = &dir_notify_enable,
1548 .maxlen = sizeof(int),
1550 .proc_handler = proc_dointvec,
1554 #ifdef CONFIG_FILE_LOCKING
1556 .procname = "lease-break-time",
1557 .data = &lease_break_time,
1558 .maxlen = sizeof(int),
1560 .proc_handler = proc_dointvec,
1565 .procname = "aio-nr",
1567 .maxlen = sizeof(aio_nr),
1569 .proc_handler = proc_doulongvec_minmax,
1572 .procname = "aio-max-nr",
1573 .data = &aio_max_nr,
1574 .maxlen = sizeof(aio_max_nr),
1576 .proc_handler = proc_doulongvec_minmax,
1578 #endif /* CONFIG_AIO */
1579 #ifdef CONFIG_INOTIFY_USER
1581 .procname = "inotify",
1583 .child = inotify_table,
1588 .procname = "epoll",
1590 .child = epoll_table,
1595 .procname = "protected_symlinks",
1596 .data = &sysctl_protected_symlinks,
1597 .maxlen = sizeof(int),
1599 .proc_handler = proc_dointvec_minmax,
1604 .procname = "protected_hardlinks",
1605 .data = &sysctl_protected_hardlinks,
1606 .maxlen = sizeof(int),
1608 .proc_handler = proc_dointvec_minmax,
1613 .procname = "suid_dumpable",
1614 .data = &suid_dumpable,
1615 .maxlen = sizeof(int),
1617 .proc_handler = proc_dointvec_minmax_coredump,
1621 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1623 .procname = "binfmt_misc",
1625 .child = binfmt_misc_table,
1629 .procname = "pipe-max-size",
1630 .data = &pipe_max_size,
1631 .maxlen = sizeof(int),
1633 .proc_handler = &pipe_proc_fn,
1634 .extra1 = &pipe_min_size,
1639 static struct ctl_table debug_table[] = {
1640 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1642 .procname = "exception-trace",
1643 .data = &show_unhandled_signals,
1644 .maxlen = sizeof(int),
1646 .proc_handler = proc_dointvec
1649 #if defined(CONFIG_OPTPROBES)
1651 .procname = "kprobes-optimization",
1652 .data = &sysctl_kprobes_optimization,
1653 .maxlen = sizeof(int),
1655 .proc_handler = proc_kprobes_optimization_handler,
1663 static struct ctl_table dev_table[] = {
1667 int __init sysctl_init(void)
1669 struct ctl_table_header *hdr;
1671 hdr = register_sysctl_table(sysctl_base_table);
1672 kmemleak_not_leak(hdr);
1676 #endif /* CONFIG_SYSCTL */
1682 #ifdef CONFIG_PROC_SYSCTL
1684 static int _proc_do_string(void* data, int maxlen, int write,
1685 void __user *buffer,
1686 size_t *lenp, loff_t *ppos)
1692 if (!data || !maxlen || !*lenp) {
1700 while (len < *lenp) {
1701 if (get_user(c, p++))
1703 if (c == 0 || c == '\n')
1709 if(copy_from_user(data, buffer, len))
1711 ((char *) data)[len] = 0;
1729 if(copy_to_user(buffer, data, len))
1732 if(put_user('\n', ((char __user *) buffer) + len))
1743 * proc_dostring - read a string sysctl
1744 * @table: the sysctl table
1745 * @write: %TRUE if this is a write to the sysctl file
1746 * @buffer: the user buffer
1747 * @lenp: the size of the user buffer
1748 * @ppos: file position
1750 * Reads/writes a string from/to the user buffer. If the kernel
1751 * buffer provided is not large enough to hold the string, the
1752 * string is truncated. The copied string is %NULL-terminated.
1753 * If the string is being read by the user process, it is copied
1754 * and a newline '\n' is added. It is truncated if the buffer is
1757 * Returns 0 on success.
1759 int proc_dostring(struct ctl_table *table, int write,
1760 void __user *buffer, size_t *lenp, loff_t *ppos)
1762 return _proc_do_string(table->data, table->maxlen, write,
1763 buffer, lenp, ppos);
1766 static size_t proc_skip_spaces(char **buf)
1769 char *tmp = skip_spaces(*buf);
1775 static void proc_skip_char(char **buf, size_t *size, const char v)
1785 #define TMPBUFLEN 22
1787 * proc_get_long - reads an ASCII formatted integer from a user buffer
1789 * @buf: a kernel buffer
1790 * @size: size of the kernel buffer
1791 * @val: this is where the number will be stored
1792 * @neg: set to %TRUE if number is negative
1793 * @perm_tr: a vector which contains the allowed trailers
1794 * @perm_tr_len: size of the perm_tr vector
1795 * @tr: pointer to store the trailer character
1797 * In case of success %0 is returned and @buf and @size are updated with
1798 * the amount of bytes read. If @tr is non-NULL and a trailing
1799 * character exists (size is non-zero after returning from this
1800 * function), @tr is updated with the trailing character.
1802 static int proc_get_long(char **buf, size_t *size,
1803 unsigned long *val, bool *neg,
1804 const char *perm_tr, unsigned perm_tr_len, char *tr)
1807 char *p, tmp[TMPBUFLEN];
1813 if (len > TMPBUFLEN - 1)
1814 len = TMPBUFLEN - 1;
1816 memcpy(tmp, *buf, len);
1820 if (*p == '-' && *size > 1) {
1828 *val = simple_strtoul(p, &p, 0);
1832 /* We don't know if the next char is whitespace thus we may accept
1833 * invalid integers (e.g. 1234...a) or two integers instead of one
1834 * (e.g. 123...1). So lets not allow such large numbers. */
1835 if (len == TMPBUFLEN - 1)
1838 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
1841 if (tr && (len < *size))
1851 * proc_put_long - converts an integer to a decimal ASCII formatted string
1853 * @buf: the user buffer
1854 * @size: the size of the user buffer
1855 * @val: the integer to be converted
1856 * @neg: sign of the number, %TRUE for negative
1858 * In case of success %0 is returned and @buf and @size are updated with
1859 * the amount of bytes written.
1861 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
1865 char tmp[TMPBUFLEN], *p = tmp;
1867 sprintf(p, "%s%lu", neg ? "-" : "", val);
1871 if (copy_to_user(*buf, tmp, len))
1879 static int proc_put_char(void __user **buf, size_t *size, char c)
1882 char __user **buffer = (char __user **)buf;
1883 if (put_user(c, *buffer))
1885 (*size)--, (*buffer)++;
1891 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
1893 int write, void *data)
1896 *valp = *negp ? -*lvalp : *lvalp;
1901 *lvalp = (unsigned long)-val;
1904 *lvalp = (unsigned long)val;
1910 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
1912 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
1913 int write, void __user *buffer,
1914 size_t *lenp, loff_t *ppos,
1915 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
1916 int write, void *data),
1919 int *i, vleft, first = 1, err = 0;
1920 unsigned long page = 0;
1924 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
1929 i = (int *) tbl_data;
1930 vleft = table->maxlen / sizeof(*i);
1934 conv = do_proc_dointvec_conv;
1937 if (left > PAGE_SIZE - 1)
1938 left = PAGE_SIZE - 1;
1939 page = __get_free_page(GFP_TEMPORARY);
1940 kbuf = (char *) page;
1943 if (copy_from_user(kbuf, buffer, left)) {
1950 for (; left && vleft--; i++, first=0) {
1955 left -= proc_skip_spaces(&kbuf);
1959 err = proc_get_long(&kbuf, &left, &lval, &neg,
1961 sizeof(proc_wspace_sep), NULL);
1964 if (conv(&neg, &lval, i, 1, data)) {
1969 if (conv(&neg, &lval, i, 0, data)) {
1974 err = proc_put_char(&buffer, &left, '\t');
1977 err = proc_put_long(&buffer, &left, lval, neg);
1983 if (!write && !first && left && !err)
1984 err = proc_put_char(&buffer, &left, '\n');
1985 if (write && !err && left)
1986 left -= proc_skip_spaces(&kbuf);
1991 return err ? : -EINVAL;
1998 static int do_proc_dointvec(struct ctl_table *table, int write,
1999 void __user *buffer, size_t *lenp, loff_t *ppos,
2000 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2001 int write, void *data),
2004 return __do_proc_dointvec(table->data, table, write,
2005 buffer, lenp, ppos, conv, data);
2009 * proc_dointvec - read a vector of integers
2010 * @table: the sysctl table
2011 * @write: %TRUE if this is a write to the sysctl file
2012 * @buffer: the user buffer
2013 * @lenp: the size of the user buffer
2014 * @ppos: file position
2016 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2017 * values from/to the user buffer, treated as an ASCII string.
2019 * Returns 0 on success.
2021 int proc_dointvec(struct ctl_table *table, int write,
2022 void __user *buffer, size_t *lenp, loff_t *ppos)
2024 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2029 * Taint values can only be increased
2030 * This means we can safely use a temporary.
2032 static int proc_taint(struct ctl_table *table, int write,
2033 void __user *buffer, size_t *lenp, loff_t *ppos)
2036 unsigned long tmptaint = get_taint();
2039 if (write && !capable(CAP_SYS_ADMIN))
2044 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2050 * Poor man's atomic or. Not worth adding a primitive
2051 * to everyone's atomic.h for this
2054 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2055 if ((tmptaint >> i) & 1)
2056 add_taint(i, LOCKDEP_STILL_OK);
2063 #ifdef CONFIG_PRINTK
2064 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2065 void __user *buffer, size_t *lenp, loff_t *ppos)
2067 if (write && !capable(CAP_SYS_ADMIN))
2070 return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2074 struct do_proc_dointvec_minmax_conv_param {
2079 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2081 int write, void *data)
2083 struct do_proc_dointvec_minmax_conv_param *param = data;
2085 int val = *negp ? -*lvalp : *lvalp;
2086 if ((param->min && *param->min > val) ||
2087 (param->max && *param->max < val))
2094 *lvalp = (unsigned long)-val;
2097 *lvalp = (unsigned long)val;
2104 * proc_dointvec_minmax - read a vector of integers with min/max values
2105 * @table: the sysctl table
2106 * @write: %TRUE if this is a write to the sysctl file
2107 * @buffer: the user buffer
2108 * @lenp: the size of the user buffer
2109 * @ppos: file position
2111 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2112 * values from/to the user buffer, treated as an ASCII string.
2114 * This routine will ensure the values are within the range specified by
2115 * table->extra1 (min) and table->extra2 (max).
2117 * Returns 0 on success.
2119 int proc_dointvec_minmax(struct ctl_table *table, int write,
2120 void __user *buffer, size_t *lenp, loff_t *ppos)
2122 struct do_proc_dointvec_minmax_conv_param param = {
2123 .min = (int *) table->extra1,
2124 .max = (int *) table->extra2,
2126 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2127 do_proc_dointvec_minmax_conv, ¶m);
2130 static void validate_coredump_safety(void)
2132 #ifdef CONFIG_COREDUMP
2133 if (suid_dumpable == SUID_DUMP_ROOT &&
2134 core_pattern[0] != '/' && core_pattern[0] != '|') {
2135 printk(KERN_WARNING "Unsafe core_pattern used with "\
2136 "suid_dumpable=2. Pipe handler or fully qualified "\
2137 "core dump path required.\n");
2142 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2143 void __user *buffer, size_t *lenp, loff_t *ppos)
2145 int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2147 validate_coredump_safety();
2151 #ifdef CONFIG_COREDUMP
2152 static int proc_dostring_coredump(struct ctl_table *table, int write,
2153 void __user *buffer, size_t *lenp, loff_t *ppos)
2155 int error = proc_dostring(table, write, buffer, lenp, ppos);
2157 validate_coredump_safety();
2162 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2163 void __user *buffer,
2164 size_t *lenp, loff_t *ppos,
2165 unsigned long convmul,
2166 unsigned long convdiv)
2168 unsigned long *i, *min, *max;
2169 int vleft, first = 1, err = 0;
2170 unsigned long page = 0;
2174 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2179 i = (unsigned long *) data;
2180 min = (unsigned long *) table->extra1;
2181 max = (unsigned long *) table->extra2;
2182 vleft = table->maxlen / sizeof(unsigned long);
2186 if (left > PAGE_SIZE - 1)
2187 left = PAGE_SIZE - 1;
2188 page = __get_free_page(GFP_TEMPORARY);
2189 kbuf = (char *) page;
2192 if (copy_from_user(kbuf, buffer, left)) {
2199 for (; left && vleft--; i++, first = 0) {
2205 left -= proc_skip_spaces(&kbuf);
2207 err = proc_get_long(&kbuf, &left, &val, &neg,
2209 sizeof(proc_wspace_sep), NULL);
2214 if ((min && val < *min) || (max && val > *max))
2218 val = convdiv * (*i) / convmul;
2220 err = proc_put_char(&buffer, &left, '\t');
2221 err = proc_put_long(&buffer, &left, val, false);
2227 if (!write && !first && left && !err)
2228 err = proc_put_char(&buffer, &left, '\n');
2230 left -= proc_skip_spaces(&kbuf);
2235 return err ? : -EINVAL;
2242 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2243 void __user *buffer,
2244 size_t *lenp, loff_t *ppos,
2245 unsigned long convmul,
2246 unsigned long convdiv)
2248 return __do_proc_doulongvec_minmax(table->data, table, write,
2249 buffer, lenp, ppos, convmul, convdiv);
2253 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2254 * @table: the sysctl table
2255 * @write: %TRUE if this is a write to the sysctl file
2256 * @buffer: the user buffer
2257 * @lenp: the size of the user buffer
2258 * @ppos: file position
2260 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2261 * values from/to the user buffer, treated as an ASCII string.
2263 * This routine will ensure the values are within the range specified by
2264 * table->extra1 (min) and table->extra2 (max).
2266 * Returns 0 on success.
2268 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2269 void __user *buffer, size_t *lenp, loff_t *ppos)
2271 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2275 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2276 * @table: the sysctl table
2277 * @write: %TRUE if this is a write to the sysctl file
2278 * @buffer: the user buffer
2279 * @lenp: the size of the user buffer
2280 * @ppos: file position
2282 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2283 * values from/to the user buffer, treated as an ASCII string. The values
2284 * are treated as milliseconds, and converted to jiffies when they are stored.
2286 * This routine will ensure the values are within the range specified by
2287 * table->extra1 (min) and table->extra2 (max).
2289 * Returns 0 on success.
2291 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2292 void __user *buffer,
2293 size_t *lenp, loff_t *ppos)
2295 return do_proc_doulongvec_minmax(table, write, buffer,
2296 lenp, ppos, HZ, 1000l);
2300 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2302 int write, void *data)
2305 if (*lvalp > LONG_MAX / HZ)
2307 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2313 lval = (unsigned long)-val;
2316 lval = (unsigned long)val;
2323 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2325 int write, void *data)
2328 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2330 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2336 lval = (unsigned long)-val;
2339 lval = (unsigned long)val;
2341 *lvalp = jiffies_to_clock_t(lval);
2346 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2348 int write, void *data)
2351 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2357 lval = (unsigned long)-val;
2360 lval = (unsigned long)val;
2362 *lvalp = jiffies_to_msecs(lval);
2368 * proc_dointvec_jiffies - read a vector of integers as seconds
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 int) integer
2376 * values from/to the user buffer, treated as an ASCII string.
2377 * The values read are assumed to be in seconds, and are converted into
2380 * Returns 0 on success.
2382 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2383 void __user *buffer, size_t *lenp, loff_t *ppos)
2385 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2386 do_proc_dointvec_jiffies_conv,NULL);
2390 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2391 * @table: the sysctl table
2392 * @write: %TRUE if this is a write to the sysctl file
2393 * @buffer: the user buffer
2394 * @lenp: the size of the user buffer
2395 * @ppos: pointer to the file position
2397 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2398 * values from/to the user buffer, treated as an ASCII string.
2399 * The values read are assumed to be in 1/USER_HZ seconds, and
2400 * are converted into jiffies.
2402 * Returns 0 on success.
2404 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2405 void __user *buffer, size_t *lenp, loff_t *ppos)
2407 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2408 do_proc_dointvec_userhz_jiffies_conv,NULL);
2412 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2413 * @table: the sysctl table
2414 * @write: %TRUE if this is a write to the sysctl file
2415 * @buffer: the user buffer
2416 * @lenp: the size of the user buffer
2417 * @ppos: file position
2418 * @ppos: the current position in the file
2420 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2421 * values from/to the user buffer, treated as an ASCII string.
2422 * The values read are assumed to be in 1/1000 seconds, and
2423 * are converted into jiffies.
2425 * Returns 0 on success.
2427 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2428 void __user *buffer, size_t *lenp, loff_t *ppos)
2430 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2431 do_proc_dointvec_ms_jiffies_conv, NULL);
2434 static int proc_do_cad_pid(struct ctl_table *table, int write,
2435 void __user *buffer, size_t *lenp, loff_t *ppos)
2437 struct pid *new_pid;
2441 tmp = pid_vnr(cad_pid);
2443 r = __do_proc_dointvec(&tmp, table, write, buffer,
2444 lenp, ppos, NULL, NULL);
2448 new_pid = find_get_pid(tmp);
2452 put_pid(xchg(&cad_pid, new_pid));
2457 * proc_do_large_bitmap - read/write from/to a large bitmap
2458 * @table: the sysctl table
2459 * @write: %TRUE if this is a write to the sysctl file
2460 * @buffer: the user buffer
2461 * @lenp: the size of the user buffer
2462 * @ppos: file position
2464 * The bitmap is stored at table->data and the bitmap length (in bits)
2467 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2468 * large bitmaps may be represented in a compact manner. Writing into
2469 * the file will clear the bitmap then update it with the given input.
2471 * Returns 0 on success.
2473 int proc_do_large_bitmap(struct ctl_table *table, int write,
2474 void __user *buffer, size_t *lenp, loff_t *ppos)
2478 size_t left = *lenp;
2479 unsigned long bitmap_len = table->maxlen;
2480 unsigned long *bitmap = (unsigned long *) table->data;
2481 unsigned long *tmp_bitmap = NULL;
2482 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2484 if (!bitmap_len || !left || (*ppos && !write)) {
2490 unsigned long page = 0;
2493 if (left > PAGE_SIZE - 1)
2494 left = PAGE_SIZE - 1;
2496 page = __get_free_page(GFP_TEMPORARY);
2497 kbuf = (char *) page;
2500 if (copy_from_user(kbuf, buffer, left)) {
2506 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2512 proc_skip_char(&kbuf, &left, '\n');
2513 while (!err && left) {
2514 unsigned long val_a, val_b;
2517 err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2521 if (val_a >= bitmap_len || neg) {
2533 err = proc_get_long(&kbuf, &left, &val_b,
2534 &neg, tr_b, sizeof(tr_b),
2538 if (val_b >= bitmap_len || neg ||
2549 bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
2551 proc_skip_char(&kbuf, &left, '\n');
2555 unsigned long bit_a, bit_b = 0;
2558 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2559 if (bit_a >= bitmap_len)
2561 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2565 err = proc_put_char(&buffer, &left, ',');
2569 err = proc_put_long(&buffer, &left, bit_a, false);
2572 if (bit_a != bit_b) {
2573 err = proc_put_char(&buffer, &left, '-');
2576 err = proc_put_long(&buffer, &left, bit_b, false);
2584 err = proc_put_char(&buffer, &left, '\n');
2590 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2592 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
2604 #else /* CONFIG_PROC_SYSCTL */
2606 int proc_dostring(struct ctl_table *table, int write,
2607 void __user *buffer, size_t *lenp, loff_t *ppos)
2612 int proc_dointvec(struct ctl_table *table, int write,
2613 void __user *buffer, size_t *lenp, loff_t *ppos)
2618 int proc_dointvec_minmax(struct ctl_table *table, int write,
2619 void __user *buffer, size_t *lenp, loff_t *ppos)
2624 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2625 void __user *buffer, size_t *lenp, loff_t *ppos)
2630 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2631 void __user *buffer, size_t *lenp, loff_t *ppos)
2636 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2637 void __user *buffer, size_t *lenp, loff_t *ppos)
2642 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2643 void __user *buffer, size_t *lenp, loff_t *ppos)
2648 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2649 void __user *buffer,
2650 size_t *lenp, loff_t *ppos)
2656 #endif /* CONFIG_PROC_SYSCTL */
2659 * No sense putting this after each symbol definition, twice,
2660 * exception granted :-)
2662 EXPORT_SYMBOL(proc_dointvec);
2663 EXPORT_SYMBOL(proc_dointvec_jiffies);
2664 EXPORT_SYMBOL(proc_dointvec_minmax);
2665 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2666 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2667 EXPORT_SYMBOL(proc_dostring);
2668 EXPORT_SYMBOL(proc_doulongvec_minmax);
2669 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);