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>
22 #include <linux/aio.h>
24 #include <linux/swap.h>
25 #include <linux/slab.h>
26 #include <linux/sysctl.h>
27 #include <linux/bitmap.h>
28 #include <linux/signal.h>
29 #include <linux/printk.h>
30 #include <linux/proc_fs.h>
31 #include <linux/security.h>
32 #include <linux/ctype.h>
33 #include <linux/kmemcheck.h>
34 #include <linux/kmemleak.h>
36 #include <linux/init.h>
37 #include <linux/kernel.h>
38 #include <linux/kobject.h>
39 #include <linux/net.h>
40 #include <linux/sysrq.h>
41 #include <linux/highuid.h>
42 #include <linux/writeback.h>
43 #include <linux/ratelimit.h>
44 #include <linux/compaction.h>
45 #include <linux/hugetlb.h>
46 #include <linux/initrd.h>
47 #include <linux/key.h>
48 #include <linux/times.h>
49 #include <linux/limits.h>
50 #include <linux/dcache.h>
51 #include <linux/dnotify.h>
52 #include <linux/syscalls.h>
53 #include <linux/vmstat.h>
54 #include <linux/nfs_fs.h>
55 #include <linux/acpi.h>
56 #include <linux/reboot.h>
57 #include <linux/ftrace.h>
58 #include <linux/perf_event.h>
59 #include <linux/kprobes.h>
60 #include <linux/pipe_fs_i.h>
61 #include <linux/oom.h>
62 #include <linux/kmod.h>
63 #include <linux/capability.h>
64 #include <linux/binfmts.h>
65 #include <linux/sched/sysctl.h>
66 #include <linux/kexec.h>
67 #include <linux/bpf.h>
69 #include <asm/uaccess.h>
70 #include <asm/processor.h>
74 #include <asm/stacktrace.h>
78 #include <asm/setup.h>
80 #ifdef CONFIG_BSD_PROCESS_ACCT
81 #include <linux/acct.h>
83 #ifdef CONFIG_RT_MUTEXES
84 #include <linux/rtmutex.h>
86 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
87 #include <linux/lockdep.h>
89 #ifdef CONFIG_CHR_DEV_SG
93 #ifdef CONFIG_LOCKUP_DETECTOR
94 #include <linux/nmi.h>
97 #if defined(CONFIG_SYSCTL)
99 /* External variables not in a header file. */
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,
353 #endif /* CONFIG_SMP */
354 #ifdef CONFIG_NUMA_BALANCING
356 .procname = "numa_balancing_scan_delay_ms",
357 .data = &sysctl_numa_balancing_scan_delay,
358 .maxlen = sizeof(unsigned int),
360 .proc_handler = proc_dointvec,
363 .procname = "numa_balancing_scan_period_min_ms",
364 .data = &sysctl_numa_balancing_scan_period_min,
365 .maxlen = sizeof(unsigned int),
367 .proc_handler = proc_dointvec,
370 .procname = "numa_balancing_scan_period_max_ms",
371 .data = &sysctl_numa_balancing_scan_period_max,
372 .maxlen = sizeof(unsigned int),
374 .proc_handler = proc_dointvec,
377 .procname = "numa_balancing_scan_size_mb",
378 .data = &sysctl_numa_balancing_scan_size,
379 .maxlen = sizeof(unsigned int),
381 .proc_handler = proc_dointvec_minmax,
385 .procname = "numa_balancing",
386 .data = NULL, /* filled in by handler */
387 .maxlen = sizeof(unsigned int),
389 .proc_handler = sysctl_numa_balancing,
393 #endif /* CONFIG_NUMA_BALANCING */
394 #endif /* CONFIG_SCHED_DEBUG */
396 .procname = "sched_rt_period_us",
397 .data = &sysctl_sched_rt_period,
398 .maxlen = sizeof(unsigned int),
400 .proc_handler = sched_rt_handler,
403 .procname = "sched_rt_runtime_us",
404 .data = &sysctl_sched_rt_runtime,
405 .maxlen = sizeof(int),
407 .proc_handler = sched_rt_handler,
410 .procname = "sched_rr_timeslice_ms",
411 .data = &sched_rr_timeslice,
412 .maxlen = sizeof(int),
414 .proc_handler = sched_rr_handler,
416 #ifdef CONFIG_SCHED_AUTOGROUP
418 .procname = "sched_autogroup_enabled",
419 .data = &sysctl_sched_autogroup_enabled,
420 .maxlen = sizeof(unsigned int),
422 .proc_handler = proc_dointvec_minmax,
427 #ifdef CONFIG_CFS_BANDWIDTH
429 .procname = "sched_cfs_bandwidth_slice_us",
430 .data = &sysctl_sched_cfs_bandwidth_slice,
431 .maxlen = sizeof(unsigned int),
433 .proc_handler = proc_dointvec_minmax,
437 #ifdef CONFIG_SCHED_TUNE
439 .procname = "sched_cfs_boost",
440 .data = &sysctl_sched_cfs_boost,
441 .maxlen = sizeof(sysctl_sched_cfs_boost),
442 #ifdef CONFIG_CGROUP_SCHEDTUNE
447 .proc_handler = &sysctl_sched_cfs_boost_handler,
449 .extra2 = &one_hundred,
452 #ifdef CONFIG_PROVE_LOCKING
454 .procname = "prove_locking",
455 .data = &prove_locking,
456 .maxlen = sizeof(int),
458 .proc_handler = proc_dointvec,
461 #ifdef CONFIG_LOCK_STAT
463 .procname = "lock_stat",
465 .maxlen = sizeof(int),
467 .proc_handler = proc_dointvec,
472 .data = &panic_timeout,
473 .maxlen = sizeof(int),
475 .proc_handler = proc_dointvec,
477 #ifdef CONFIG_COREDUMP
479 .procname = "core_uses_pid",
480 .data = &core_uses_pid,
481 .maxlen = sizeof(int),
483 .proc_handler = proc_dointvec,
486 .procname = "core_pattern",
487 .data = core_pattern,
488 .maxlen = CORENAME_MAX_SIZE,
490 .proc_handler = proc_dostring_coredump,
493 .procname = "core_pipe_limit",
494 .data = &core_pipe_limit,
495 .maxlen = sizeof(unsigned int),
497 .proc_handler = proc_dointvec,
500 #ifdef CONFIG_PROC_SYSCTL
502 .procname = "tainted",
503 .maxlen = sizeof(long),
505 .proc_handler = proc_taint,
508 .procname = "sysctl_writes_strict",
509 .data = &sysctl_writes_strict,
510 .maxlen = sizeof(int),
512 .proc_handler = proc_dointvec_minmax,
517 #ifdef CONFIG_LATENCYTOP
519 .procname = "latencytop",
520 .data = &latencytop_enabled,
521 .maxlen = sizeof(int),
523 .proc_handler = proc_dointvec,
526 #ifdef CONFIG_BLK_DEV_INITRD
528 .procname = "real-root-dev",
529 .data = &real_root_dev,
530 .maxlen = sizeof(int),
532 .proc_handler = proc_dointvec,
536 .procname = "print-fatal-signals",
537 .data = &print_fatal_signals,
538 .maxlen = sizeof(int),
540 .proc_handler = proc_dointvec,
544 .procname = "reboot-cmd",
545 .data = reboot_command,
548 .proc_handler = proc_dostring,
551 .procname = "stop-a",
552 .data = &stop_a_enabled,
553 .maxlen = sizeof (int),
555 .proc_handler = proc_dointvec,
558 .procname = "scons-poweroff",
559 .data = &scons_pwroff,
560 .maxlen = sizeof (int),
562 .proc_handler = proc_dointvec,
565 #ifdef CONFIG_SPARC64
567 .procname = "tsb-ratio",
568 .data = &sysctl_tsb_ratio,
569 .maxlen = sizeof (int),
571 .proc_handler = proc_dointvec,
576 .procname = "soft-power",
577 .data = &pwrsw_enabled,
578 .maxlen = sizeof (int),
580 .proc_handler = proc_dointvec,
583 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
585 .procname = "unaligned-trap",
586 .data = &unaligned_enabled,
587 .maxlen = sizeof (int),
589 .proc_handler = proc_dointvec,
593 .procname = "ctrl-alt-del",
595 .maxlen = sizeof(int),
597 .proc_handler = proc_dointvec,
599 #ifdef CONFIG_FUNCTION_TRACER
601 .procname = "ftrace_enabled",
602 .data = &ftrace_enabled,
603 .maxlen = sizeof(int),
605 .proc_handler = ftrace_enable_sysctl,
608 #ifdef CONFIG_STACK_TRACER
610 .procname = "stack_tracer_enabled",
611 .data = &stack_tracer_enabled,
612 .maxlen = sizeof(int),
614 .proc_handler = stack_trace_sysctl,
617 #ifdef CONFIG_TRACING
619 .procname = "ftrace_dump_on_oops",
620 .data = &ftrace_dump_on_oops,
621 .maxlen = sizeof(int),
623 .proc_handler = proc_dointvec,
626 .procname = "traceoff_on_warning",
627 .data = &__disable_trace_on_warning,
628 .maxlen = sizeof(__disable_trace_on_warning),
630 .proc_handler = proc_dointvec,
633 .procname = "tracepoint_printk",
634 .data = &tracepoint_printk,
635 .maxlen = sizeof(tracepoint_printk),
637 .proc_handler = proc_dointvec,
640 #ifdef CONFIG_KEXEC_CORE
642 .procname = "kexec_load_disabled",
643 .data = &kexec_load_disabled,
644 .maxlen = sizeof(int),
646 /* only handle a transition from default "0" to "1" */
647 .proc_handler = proc_dointvec_minmax,
652 #ifdef CONFIG_MODULES
654 .procname = "modprobe",
655 .data = &modprobe_path,
656 .maxlen = KMOD_PATH_LEN,
658 .proc_handler = proc_dostring,
661 .procname = "modules_disabled",
662 .data = &modules_disabled,
663 .maxlen = sizeof(int),
665 /* only handle a transition from default "0" to "1" */
666 .proc_handler = proc_dointvec_minmax,
671 #ifdef CONFIG_UEVENT_HELPER
673 .procname = "hotplug",
674 .data = &uevent_helper,
675 .maxlen = UEVENT_HELPER_PATH_LEN,
677 .proc_handler = proc_dostring,
680 #ifdef CONFIG_CHR_DEV_SG
682 .procname = "sg-big-buff",
683 .data = &sg_big_buff,
684 .maxlen = sizeof (int),
686 .proc_handler = proc_dointvec,
689 #ifdef CONFIG_BSD_PROCESS_ACCT
693 .maxlen = 3*sizeof(int),
695 .proc_handler = proc_dointvec,
698 #ifdef CONFIG_MAGIC_SYSRQ
701 .data = &__sysrq_enabled,
702 .maxlen = sizeof (int),
704 .proc_handler = sysrq_sysctl_handler,
707 #ifdef CONFIG_PROC_SYSCTL
709 .procname = "cad_pid",
711 .maxlen = sizeof (int),
713 .proc_handler = proc_do_cad_pid,
717 .procname = "threads-max",
719 .maxlen = sizeof(int),
721 .proc_handler = sysctl_max_threads,
724 .procname = "random",
726 .child = random_table,
729 .procname = "usermodehelper",
731 .child = usermodehelper_table,
734 .procname = "overflowuid",
735 .data = &overflowuid,
736 .maxlen = sizeof(int),
738 .proc_handler = proc_dointvec_minmax,
739 .extra1 = &minolduid,
740 .extra2 = &maxolduid,
743 .procname = "overflowgid",
744 .data = &overflowgid,
745 .maxlen = sizeof(int),
747 .proc_handler = proc_dointvec_minmax,
748 .extra1 = &minolduid,
749 .extra2 = &maxolduid,
752 #ifdef CONFIG_MATHEMU
754 .procname = "ieee_emulation_warnings",
755 .data = &sysctl_ieee_emulation_warnings,
756 .maxlen = sizeof(int),
758 .proc_handler = proc_dointvec,
762 .procname = "userprocess_debug",
763 .data = &show_unhandled_signals,
764 .maxlen = sizeof(int),
766 .proc_handler = proc_dointvec,
770 .procname = "pid_max",
772 .maxlen = sizeof (int),
774 .proc_handler = proc_dointvec_minmax,
775 .extra1 = &pid_max_min,
776 .extra2 = &pid_max_max,
779 .procname = "panic_on_oops",
780 .data = &panic_on_oops,
781 .maxlen = sizeof(int),
783 .proc_handler = proc_dointvec,
785 #if defined CONFIG_PRINTK
787 .procname = "printk",
788 .data = &console_loglevel,
789 .maxlen = 4*sizeof(int),
791 .proc_handler = proc_dointvec,
794 .procname = "printk_ratelimit",
795 .data = &printk_ratelimit_state.interval,
796 .maxlen = sizeof(int),
798 .proc_handler = proc_dointvec_jiffies,
801 .procname = "printk_ratelimit_burst",
802 .data = &printk_ratelimit_state.burst,
803 .maxlen = sizeof(int),
805 .proc_handler = proc_dointvec,
808 .procname = "printk_delay",
809 .data = &printk_delay_msec,
810 .maxlen = sizeof(int),
812 .proc_handler = proc_dointvec_minmax,
814 .extra2 = &ten_thousand,
817 .procname = "dmesg_restrict",
818 .data = &dmesg_restrict,
819 .maxlen = sizeof(int),
821 .proc_handler = proc_dointvec_minmax_sysadmin,
826 .procname = "kptr_restrict",
827 .data = &kptr_restrict,
828 .maxlen = sizeof(int),
830 .proc_handler = proc_dointvec_minmax_sysadmin,
836 .procname = "ngroups_max",
837 .data = &ngroups_max,
838 .maxlen = sizeof (int),
840 .proc_handler = proc_dointvec,
843 .procname = "cap_last_cap",
844 .data = (void *)&cap_last_cap,
845 .maxlen = sizeof(int),
847 .proc_handler = proc_dointvec,
849 #if defined(CONFIG_LOCKUP_DETECTOR)
851 .procname = "watchdog",
852 .data = &watchdog_user_enabled,
853 .maxlen = sizeof (int),
855 .proc_handler = proc_watchdog,
860 .procname = "watchdog_thresh",
861 .data = &watchdog_thresh,
862 .maxlen = sizeof(int),
864 .proc_handler = proc_watchdog_thresh,
869 .procname = "nmi_watchdog",
870 .data = &nmi_watchdog_enabled,
871 .maxlen = sizeof (int),
873 .proc_handler = proc_nmi_watchdog,
875 #if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)
882 .procname = "soft_watchdog",
883 .data = &soft_watchdog_enabled,
884 .maxlen = sizeof (int),
886 .proc_handler = proc_soft_watchdog,
891 .procname = "watchdog_cpumask",
892 .data = &watchdog_cpumask_bits,
895 .proc_handler = proc_watchdog_cpumask,
898 .procname = "softlockup_panic",
899 .data = &softlockup_panic,
900 .maxlen = sizeof(int),
902 .proc_handler = proc_dointvec_minmax,
906 #ifdef CONFIG_HARDLOCKUP_DETECTOR
908 .procname = "hardlockup_panic",
909 .data = &hardlockup_panic,
910 .maxlen = sizeof(int),
912 .proc_handler = proc_dointvec_minmax,
919 .procname = "softlockup_all_cpu_backtrace",
920 .data = &sysctl_softlockup_all_cpu_backtrace,
921 .maxlen = sizeof(int),
923 .proc_handler = proc_dointvec_minmax,
928 .procname = "hardlockup_all_cpu_backtrace",
929 .data = &sysctl_hardlockup_all_cpu_backtrace,
930 .maxlen = sizeof(int),
932 .proc_handler = proc_dointvec_minmax,
936 #endif /* CONFIG_SMP */
938 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
940 .procname = "unknown_nmi_panic",
941 .data = &unknown_nmi_panic,
942 .maxlen = sizeof (int),
944 .proc_handler = proc_dointvec,
947 #if defined(CONFIG_X86)
949 .procname = "panic_on_unrecovered_nmi",
950 .data = &panic_on_unrecovered_nmi,
951 .maxlen = sizeof(int),
953 .proc_handler = proc_dointvec,
956 .procname = "panic_on_io_nmi",
957 .data = &panic_on_io_nmi,
958 .maxlen = sizeof(int),
960 .proc_handler = proc_dointvec,
962 #ifdef CONFIG_DEBUG_STACKOVERFLOW
964 .procname = "panic_on_stackoverflow",
965 .data = &sysctl_panic_on_stackoverflow,
966 .maxlen = sizeof(int),
968 .proc_handler = proc_dointvec,
972 .procname = "bootloader_type",
973 .data = &bootloader_type,
974 .maxlen = sizeof (int),
976 .proc_handler = proc_dointvec,
979 .procname = "bootloader_version",
980 .data = &bootloader_version,
981 .maxlen = sizeof (int),
983 .proc_handler = proc_dointvec,
986 .procname = "kstack_depth_to_print",
987 .data = &kstack_depth_to_print,
988 .maxlen = sizeof(int),
990 .proc_handler = proc_dointvec,
993 .procname = "io_delay_type",
994 .data = &io_delay_type,
995 .maxlen = sizeof(int),
997 .proc_handler = proc_dointvec,
1000 #if defined(CONFIG_MMU)
1002 .procname = "randomize_va_space",
1003 .data = &randomize_va_space,
1004 .maxlen = sizeof(int),
1006 .proc_handler = proc_dointvec,
1009 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1011 .procname = "spin_retry",
1012 .data = &spin_retry,
1013 .maxlen = sizeof (int),
1015 .proc_handler = proc_dointvec,
1018 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1020 .procname = "acpi_video_flags",
1021 .data = &acpi_realmode_flags,
1022 .maxlen = sizeof (unsigned long),
1024 .proc_handler = proc_doulongvec_minmax,
1027 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1029 .procname = "ignore-unaligned-usertrap",
1030 .data = &no_unaligned_warning,
1031 .maxlen = sizeof (int),
1033 .proc_handler = proc_dointvec,
1038 .procname = "unaligned-dump-stack",
1039 .data = &unaligned_dump_stack,
1040 .maxlen = sizeof (int),
1042 .proc_handler = proc_dointvec,
1045 #ifdef CONFIG_DETECT_HUNG_TASK
1047 .procname = "hung_task_panic",
1048 .data = &sysctl_hung_task_panic,
1049 .maxlen = sizeof(int),
1051 .proc_handler = proc_dointvec_minmax,
1056 .procname = "hung_task_check_count",
1057 .data = &sysctl_hung_task_check_count,
1058 .maxlen = sizeof(int),
1060 .proc_handler = proc_dointvec_minmax,
1064 .procname = "hung_task_timeout_secs",
1065 .data = &sysctl_hung_task_timeout_secs,
1066 .maxlen = sizeof(unsigned long),
1068 .proc_handler = proc_dohung_task_timeout_secs,
1069 .extra2 = &hung_task_timeout_max,
1072 .procname = "hung_task_warnings",
1073 .data = &sysctl_hung_task_warnings,
1074 .maxlen = sizeof(int),
1076 .proc_handler = proc_dointvec_minmax,
1080 #ifdef CONFIG_COMPAT
1082 .procname = "compat-log",
1083 .data = &compat_log,
1084 .maxlen = sizeof (int),
1086 .proc_handler = proc_dointvec,
1089 #ifdef CONFIG_RT_MUTEXES
1091 .procname = "max_lock_depth",
1092 .data = &max_lock_depth,
1093 .maxlen = sizeof(int),
1095 .proc_handler = proc_dointvec,
1099 .procname = "poweroff_cmd",
1100 .data = &poweroff_cmd,
1101 .maxlen = POWEROFF_CMD_PATH_LEN,
1103 .proc_handler = proc_dostring,
1109 .child = key_sysctls,
1112 #ifdef CONFIG_PERF_EVENTS
1114 * User-space scripts rely on the existence of this file
1115 * as a feature check for perf_events being enabled.
1117 * So it's an ABI, do not remove!
1120 .procname = "perf_event_paranoid",
1121 .data = &sysctl_perf_event_paranoid,
1122 .maxlen = sizeof(sysctl_perf_event_paranoid),
1124 .proc_handler = proc_dointvec,
1127 .procname = "perf_event_mlock_kb",
1128 .data = &sysctl_perf_event_mlock,
1129 .maxlen = sizeof(sysctl_perf_event_mlock),
1131 .proc_handler = proc_dointvec,
1134 .procname = "perf_event_max_sample_rate",
1135 .data = &sysctl_perf_event_sample_rate,
1136 .maxlen = sizeof(sysctl_perf_event_sample_rate),
1138 .proc_handler = perf_proc_update_handler,
1142 .procname = "perf_cpu_time_max_percent",
1143 .data = &sysctl_perf_cpu_time_max_percent,
1144 .maxlen = sizeof(sysctl_perf_cpu_time_max_percent),
1146 .proc_handler = perf_cpu_time_max_percent_handler,
1148 .extra2 = &one_hundred,
1151 #ifdef CONFIG_KMEMCHECK
1153 .procname = "kmemcheck",
1154 .data = &kmemcheck_enabled,
1155 .maxlen = sizeof(int),
1157 .proc_handler = proc_dointvec,
1161 .procname = "panic_on_warn",
1162 .data = &panic_on_warn,
1163 .maxlen = sizeof(int),
1165 .proc_handler = proc_dointvec_minmax,
1169 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1171 .procname = "timer_migration",
1172 .data = &sysctl_timer_migration,
1173 .maxlen = sizeof(unsigned int),
1175 .proc_handler = timer_migration_handler,
1178 #ifdef CONFIG_BPF_SYSCALL
1180 .procname = "unprivileged_bpf_disabled",
1181 .data = &sysctl_unprivileged_bpf_disabled,
1182 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled),
1184 /* only handle a transition from default "0" to "1" */
1185 .proc_handler = proc_dointvec_minmax,
1193 static struct ctl_table vm_table[] = {
1195 .procname = "overcommit_memory",
1196 .data = &sysctl_overcommit_memory,
1197 .maxlen = sizeof(sysctl_overcommit_memory),
1199 .proc_handler = proc_dointvec_minmax,
1204 .procname = "panic_on_oom",
1205 .data = &sysctl_panic_on_oom,
1206 .maxlen = sizeof(sysctl_panic_on_oom),
1208 .proc_handler = proc_dointvec_minmax,
1213 .procname = "oom_kill_allocating_task",
1214 .data = &sysctl_oom_kill_allocating_task,
1215 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1217 .proc_handler = proc_dointvec,
1220 .procname = "oom_dump_tasks",
1221 .data = &sysctl_oom_dump_tasks,
1222 .maxlen = sizeof(sysctl_oom_dump_tasks),
1224 .proc_handler = proc_dointvec,
1227 .procname = "overcommit_ratio",
1228 .data = &sysctl_overcommit_ratio,
1229 .maxlen = sizeof(sysctl_overcommit_ratio),
1231 .proc_handler = overcommit_ratio_handler,
1234 .procname = "overcommit_kbytes",
1235 .data = &sysctl_overcommit_kbytes,
1236 .maxlen = sizeof(sysctl_overcommit_kbytes),
1238 .proc_handler = overcommit_kbytes_handler,
1241 .procname = "page-cluster",
1242 .data = &page_cluster,
1243 .maxlen = sizeof(int),
1245 .proc_handler = proc_dointvec_minmax,
1249 .procname = "dirty_background_ratio",
1250 .data = &dirty_background_ratio,
1251 .maxlen = sizeof(dirty_background_ratio),
1253 .proc_handler = dirty_background_ratio_handler,
1255 .extra2 = &one_hundred,
1258 .procname = "dirty_background_bytes",
1259 .data = &dirty_background_bytes,
1260 .maxlen = sizeof(dirty_background_bytes),
1262 .proc_handler = dirty_background_bytes_handler,
1266 .procname = "dirty_ratio",
1267 .data = &vm_dirty_ratio,
1268 .maxlen = sizeof(vm_dirty_ratio),
1270 .proc_handler = dirty_ratio_handler,
1272 .extra2 = &one_hundred,
1275 .procname = "dirty_bytes",
1276 .data = &vm_dirty_bytes,
1277 .maxlen = sizeof(vm_dirty_bytes),
1279 .proc_handler = dirty_bytes_handler,
1280 .extra1 = &dirty_bytes_min,
1283 .procname = "dirty_writeback_centisecs",
1284 .data = &dirty_writeback_interval,
1285 .maxlen = sizeof(dirty_writeback_interval),
1287 .proc_handler = dirty_writeback_centisecs_handler,
1290 .procname = "dirty_expire_centisecs",
1291 .data = &dirty_expire_interval,
1292 .maxlen = sizeof(dirty_expire_interval),
1294 .proc_handler = proc_dointvec_minmax,
1298 .procname = "dirtytime_expire_seconds",
1299 .data = &dirtytime_expire_interval,
1300 .maxlen = sizeof(dirty_expire_interval),
1302 .proc_handler = dirtytime_interval_handler,
1306 .procname = "nr_pdflush_threads",
1307 .mode = 0444 /* read-only */,
1308 .proc_handler = pdflush_proc_obsolete,
1311 .procname = "swappiness",
1312 .data = &vm_swappiness,
1313 .maxlen = sizeof(vm_swappiness),
1315 .proc_handler = proc_dointvec_minmax,
1317 .extra2 = &one_hundred,
1319 #ifdef CONFIG_HUGETLB_PAGE
1321 .procname = "nr_hugepages",
1323 .maxlen = sizeof(unsigned long),
1325 .proc_handler = hugetlb_sysctl_handler,
1329 .procname = "nr_hugepages_mempolicy",
1331 .maxlen = sizeof(unsigned long),
1333 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1337 .procname = "hugetlb_shm_group",
1338 .data = &sysctl_hugetlb_shm_group,
1339 .maxlen = sizeof(gid_t),
1341 .proc_handler = proc_dointvec,
1344 .procname = "hugepages_treat_as_movable",
1345 .data = &hugepages_treat_as_movable,
1346 .maxlen = sizeof(int),
1348 .proc_handler = proc_dointvec,
1351 .procname = "nr_overcommit_hugepages",
1353 .maxlen = sizeof(unsigned long),
1355 .proc_handler = hugetlb_overcommit_handler,
1359 .procname = "lowmem_reserve_ratio",
1360 .data = &sysctl_lowmem_reserve_ratio,
1361 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1363 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1366 .procname = "drop_caches",
1367 .data = &sysctl_drop_caches,
1368 .maxlen = sizeof(int),
1370 .proc_handler = drop_caches_sysctl_handler,
1374 #ifdef CONFIG_COMPACTION
1376 .procname = "compact_memory",
1377 .data = &sysctl_compact_memory,
1378 .maxlen = sizeof(int),
1380 .proc_handler = sysctl_compaction_handler,
1383 .procname = "extfrag_threshold",
1384 .data = &sysctl_extfrag_threshold,
1385 .maxlen = sizeof(int),
1387 .proc_handler = sysctl_extfrag_handler,
1388 .extra1 = &min_extfrag_threshold,
1389 .extra2 = &max_extfrag_threshold,
1392 .procname = "compact_unevictable_allowed",
1393 .data = &sysctl_compact_unevictable_allowed,
1394 .maxlen = sizeof(int),
1396 .proc_handler = proc_dointvec,
1401 #endif /* CONFIG_COMPACTION */
1403 .procname = "min_free_kbytes",
1404 .data = &min_free_kbytes,
1405 .maxlen = sizeof(min_free_kbytes),
1407 .proc_handler = min_free_kbytes_sysctl_handler,
1411 .procname = "percpu_pagelist_fraction",
1412 .data = &percpu_pagelist_fraction,
1413 .maxlen = sizeof(percpu_pagelist_fraction),
1415 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1420 .procname = "max_map_count",
1421 .data = &sysctl_max_map_count,
1422 .maxlen = sizeof(sysctl_max_map_count),
1424 .proc_handler = proc_dointvec_minmax,
1429 .procname = "nr_trim_pages",
1430 .data = &sysctl_nr_trim_pages,
1431 .maxlen = sizeof(sysctl_nr_trim_pages),
1433 .proc_handler = proc_dointvec_minmax,
1438 .procname = "laptop_mode",
1439 .data = &laptop_mode,
1440 .maxlen = sizeof(laptop_mode),
1442 .proc_handler = proc_dointvec_jiffies,
1445 .procname = "block_dump",
1446 .data = &block_dump,
1447 .maxlen = sizeof(block_dump),
1449 .proc_handler = proc_dointvec,
1453 .procname = "vfs_cache_pressure",
1454 .data = &sysctl_vfs_cache_pressure,
1455 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1457 .proc_handler = proc_dointvec,
1460 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1462 .procname = "legacy_va_layout",
1463 .data = &sysctl_legacy_va_layout,
1464 .maxlen = sizeof(sysctl_legacy_va_layout),
1466 .proc_handler = proc_dointvec,
1472 .procname = "zone_reclaim_mode",
1473 .data = &zone_reclaim_mode,
1474 .maxlen = sizeof(zone_reclaim_mode),
1476 .proc_handler = proc_dointvec,
1480 .procname = "min_unmapped_ratio",
1481 .data = &sysctl_min_unmapped_ratio,
1482 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1484 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1486 .extra2 = &one_hundred,
1489 .procname = "min_slab_ratio",
1490 .data = &sysctl_min_slab_ratio,
1491 .maxlen = sizeof(sysctl_min_slab_ratio),
1493 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1495 .extra2 = &one_hundred,
1500 .procname = "stat_interval",
1501 .data = &sysctl_stat_interval,
1502 .maxlen = sizeof(sysctl_stat_interval),
1504 .proc_handler = proc_dointvec_jiffies,
1509 .procname = "mmap_min_addr",
1510 .data = &dac_mmap_min_addr,
1511 .maxlen = sizeof(unsigned long),
1513 .proc_handler = mmap_min_addr_handler,
1518 .procname = "numa_zonelist_order",
1519 .data = &numa_zonelist_order,
1520 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1522 .proc_handler = numa_zonelist_order_handler,
1525 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1526 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1528 .procname = "vdso_enabled",
1529 #ifdef CONFIG_X86_32
1530 .data = &vdso32_enabled,
1531 .maxlen = sizeof(vdso32_enabled),
1533 .data = &vdso_enabled,
1534 .maxlen = sizeof(vdso_enabled),
1537 .proc_handler = proc_dointvec,
1541 #ifdef CONFIG_HIGHMEM
1543 .procname = "highmem_is_dirtyable",
1544 .data = &vm_highmem_is_dirtyable,
1545 .maxlen = sizeof(vm_highmem_is_dirtyable),
1547 .proc_handler = proc_dointvec_minmax,
1552 #ifdef CONFIG_MEMORY_FAILURE
1554 .procname = "memory_failure_early_kill",
1555 .data = &sysctl_memory_failure_early_kill,
1556 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1558 .proc_handler = proc_dointvec_minmax,
1563 .procname = "memory_failure_recovery",
1564 .data = &sysctl_memory_failure_recovery,
1565 .maxlen = sizeof(sysctl_memory_failure_recovery),
1567 .proc_handler = proc_dointvec_minmax,
1573 .procname = "user_reserve_kbytes",
1574 .data = &sysctl_user_reserve_kbytes,
1575 .maxlen = sizeof(sysctl_user_reserve_kbytes),
1577 .proc_handler = proc_doulongvec_minmax,
1580 .procname = "admin_reserve_kbytes",
1581 .data = &sysctl_admin_reserve_kbytes,
1582 .maxlen = sizeof(sysctl_admin_reserve_kbytes),
1584 .proc_handler = proc_doulongvec_minmax,
1589 static struct ctl_table fs_table[] = {
1591 .procname = "inode-nr",
1592 .data = &inodes_stat,
1593 .maxlen = 2*sizeof(long),
1595 .proc_handler = proc_nr_inodes,
1598 .procname = "inode-state",
1599 .data = &inodes_stat,
1600 .maxlen = 7*sizeof(long),
1602 .proc_handler = proc_nr_inodes,
1605 .procname = "file-nr",
1606 .data = &files_stat,
1607 .maxlen = sizeof(files_stat),
1609 .proc_handler = proc_nr_files,
1612 .procname = "file-max",
1613 .data = &files_stat.max_files,
1614 .maxlen = sizeof(files_stat.max_files),
1616 .proc_handler = proc_doulongvec_minmax,
1619 .procname = "nr_open",
1620 .data = &sysctl_nr_open,
1621 .maxlen = sizeof(int),
1623 .proc_handler = proc_dointvec_minmax,
1624 .extra1 = &sysctl_nr_open_min,
1625 .extra2 = &sysctl_nr_open_max,
1628 .procname = "dentry-state",
1629 .data = &dentry_stat,
1630 .maxlen = 6*sizeof(long),
1632 .proc_handler = proc_nr_dentry,
1635 .procname = "overflowuid",
1636 .data = &fs_overflowuid,
1637 .maxlen = sizeof(int),
1639 .proc_handler = proc_dointvec_minmax,
1640 .extra1 = &minolduid,
1641 .extra2 = &maxolduid,
1644 .procname = "overflowgid",
1645 .data = &fs_overflowgid,
1646 .maxlen = sizeof(int),
1648 .proc_handler = proc_dointvec_minmax,
1649 .extra1 = &minolduid,
1650 .extra2 = &maxolduid,
1652 #ifdef CONFIG_FILE_LOCKING
1654 .procname = "leases-enable",
1655 .data = &leases_enable,
1656 .maxlen = sizeof(int),
1658 .proc_handler = proc_dointvec,
1661 #ifdef CONFIG_DNOTIFY
1663 .procname = "dir-notify-enable",
1664 .data = &dir_notify_enable,
1665 .maxlen = sizeof(int),
1667 .proc_handler = proc_dointvec,
1671 #ifdef CONFIG_FILE_LOCKING
1673 .procname = "lease-break-time",
1674 .data = &lease_break_time,
1675 .maxlen = sizeof(int),
1677 .proc_handler = proc_dointvec,
1682 .procname = "aio-nr",
1684 .maxlen = sizeof(aio_nr),
1686 .proc_handler = proc_doulongvec_minmax,
1689 .procname = "aio-max-nr",
1690 .data = &aio_max_nr,
1691 .maxlen = sizeof(aio_max_nr),
1693 .proc_handler = proc_doulongvec_minmax,
1695 #endif /* CONFIG_AIO */
1696 #ifdef CONFIG_INOTIFY_USER
1698 .procname = "inotify",
1700 .child = inotify_table,
1705 .procname = "epoll",
1707 .child = epoll_table,
1712 .procname = "protected_symlinks",
1713 .data = &sysctl_protected_symlinks,
1714 .maxlen = sizeof(int),
1716 .proc_handler = proc_dointvec_minmax,
1721 .procname = "protected_hardlinks",
1722 .data = &sysctl_protected_hardlinks,
1723 .maxlen = sizeof(int),
1725 .proc_handler = proc_dointvec_minmax,
1730 .procname = "suid_dumpable",
1731 .data = &suid_dumpable,
1732 .maxlen = sizeof(int),
1734 .proc_handler = proc_dointvec_minmax_coredump,
1738 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1740 .procname = "binfmt_misc",
1742 .child = sysctl_mount_point,
1746 .procname = "pipe-max-size",
1747 .data = &pipe_max_size,
1748 .maxlen = sizeof(int),
1750 .proc_handler = &pipe_proc_fn,
1751 .extra1 = &pipe_min_size,
1756 static struct ctl_table debug_table[] = {
1757 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1759 .procname = "exception-trace",
1760 .data = &show_unhandled_signals,
1761 .maxlen = sizeof(int),
1763 .proc_handler = proc_dointvec
1766 #if defined(CONFIG_OPTPROBES)
1768 .procname = "kprobes-optimization",
1769 .data = &sysctl_kprobes_optimization,
1770 .maxlen = sizeof(int),
1772 .proc_handler = proc_kprobes_optimization_handler,
1780 static struct ctl_table dev_table[] = {
1784 int __init sysctl_init(void)
1786 struct ctl_table_header *hdr;
1788 hdr = register_sysctl_table(sysctl_base_table);
1789 kmemleak_not_leak(hdr);
1793 #endif /* CONFIG_SYSCTL */
1799 #ifdef CONFIG_PROC_SYSCTL
1801 static int _proc_do_string(char *data, int maxlen, int write,
1802 char __user *buffer,
1803 size_t *lenp, loff_t *ppos)
1809 if (!data || !maxlen || !*lenp) {
1815 if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
1816 /* Only continue writes not past the end of buffer. */
1818 if (len > maxlen - 1)
1825 /* Start writing from beginning of buffer. */
1831 while ((p - buffer) < *lenp && len < maxlen - 1) {
1832 if (get_user(c, p++))
1834 if (c == 0 || c == '\n')
1855 if (copy_to_user(buffer, data, len))
1858 if (put_user('\n', buffer + len))
1868 static void warn_sysctl_write(struct ctl_table *table)
1870 pr_warn_once("%s wrote to %s when file position was not 0!\n"
1871 "This will not be supported in the future. To silence this\n"
1872 "warning, set kernel.sysctl_writes_strict = -1\n",
1873 current->comm, table->procname);
1877 * proc_dostring - read a string sysctl
1878 * @table: the sysctl table
1879 * @write: %TRUE if this is a write to the sysctl file
1880 * @buffer: the user buffer
1881 * @lenp: the size of the user buffer
1882 * @ppos: file position
1884 * Reads/writes a string from/to the user buffer. If the kernel
1885 * buffer provided is not large enough to hold the string, the
1886 * string is truncated. The copied string is %NULL-terminated.
1887 * If the string is being read by the user process, it is copied
1888 * and a newline '\n' is added. It is truncated if the buffer is
1891 * Returns 0 on success.
1893 int proc_dostring(struct ctl_table *table, int write,
1894 void __user *buffer, size_t *lenp, loff_t *ppos)
1896 if (write && *ppos && sysctl_writes_strict == SYSCTL_WRITES_WARN)
1897 warn_sysctl_write(table);
1899 return _proc_do_string((char *)(table->data), table->maxlen, write,
1900 (char __user *)buffer, lenp, ppos);
1903 static size_t proc_skip_spaces(char **buf)
1906 char *tmp = skip_spaces(*buf);
1912 static void proc_skip_char(char **buf, size_t *size, const char v)
1922 #define TMPBUFLEN 22
1924 * proc_get_long - reads an ASCII formatted integer from a user buffer
1926 * @buf: a kernel buffer
1927 * @size: size of the kernel buffer
1928 * @val: this is where the number will be stored
1929 * @neg: set to %TRUE if number is negative
1930 * @perm_tr: a vector which contains the allowed trailers
1931 * @perm_tr_len: size of the perm_tr vector
1932 * @tr: pointer to store the trailer character
1934 * In case of success %0 is returned and @buf and @size are updated with
1935 * the amount of bytes read. If @tr is non-NULL and a trailing
1936 * character exists (size is non-zero after returning from this
1937 * function), @tr is updated with the trailing character.
1939 static int proc_get_long(char **buf, size_t *size,
1940 unsigned long *val, bool *neg,
1941 const char *perm_tr, unsigned perm_tr_len, char *tr)
1944 char *p, tmp[TMPBUFLEN];
1950 if (len > TMPBUFLEN - 1)
1951 len = TMPBUFLEN - 1;
1953 memcpy(tmp, *buf, len);
1957 if (*p == '-' && *size > 1) {
1965 *val = simple_strtoul(p, &p, 0);
1969 /* We don't know if the next char is whitespace thus we may accept
1970 * invalid integers (e.g. 1234...a) or two integers instead of one
1971 * (e.g. 123...1). So lets not allow such large numbers. */
1972 if (len == TMPBUFLEN - 1)
1975 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
1978 if (tr && (len < *size))
1988 * proc_put_long - converts an integer to a decimal ASCII formatted string
1990 * @buf: the user buffer
1991 * @size: the size of the user buffer
1992 * @val: the integer to be converted
1993 * @neg: sign of the number, %TRUE for negative
1995 * In case of success %0 is returned and @buf and @size are updated with
1996 * the amount of bytes written.
1998 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2002 char tmp[TMPBUFLEN], *p = tmp;
2004 sprintf(p, "%s%lu", neg ? "-" : "", val);
2008 if (copy_to_user(*buf, tmp, len))
2016 static int proc_put_char(void __user **buf, size_t *size, char c)
2019 char __user **buffer = (char __user **)buf;
2020 if (put_user(c, *buffer))
2022 (*size)--, (*buffer)++;
2028 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2030 int write, void *data)
2034 if (*lvalp > (unsigned long) INT_MAX + 1)
2038 if (*lvalp > (unsigned long) INT_MAX)
2046 *lvalp = -(unsigned long)val;
2049 *lvalp = (unsigned long)val;
2055 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2057 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2058 int write, void __user *buffer,
2059 size_t *lenp, loff_t *ppos,
2060 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2061 int write, void *data),
2064 int *i, vleft, first = 1, err = 0;
2065 unsigned long page = 0;
2069 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2074 i = (int *) tbl_data;
2075 vleft = table->maxlen / sizeof(*i);
2079 conv = do_proc_dointvec_conv;
2083 switch (sysctl_writes_strict) {
2084 case SYSCTL_WRITES_STRICT:
2086 case SYSCTL_WRITES_WARN:
2087 warn_sysctl_write(table);
2094 if (left > PAGE_SIZE - 1)
2095 left = PAGE_SIZE - 1;
2096 page = __get_free_page(GFP_TEMPORARY);
2097 kbuf = (char *) page;
2100 if (copy_from_user(kbuf, buffer, left)) {
2107 for (; left && vleft--; i++, first=0) {
2112 left -= proc_skip_spaces(&kbuf);
2116 err = proc_get_long(&kbuf, &left, &lval, &neg,
2118 sizeof(proc_wspace_sep), NULL);
2121 if (conv(&neg, &lval, i, 1, data)) {
2126 if (conv(&neg, &lval, i, 0, data)) {
2131 err = proc_put_char(&buffer, &left, '\t');
2134 err = proc_put_long(&buffer, &left, lval, neg);
2140 if (!write && !first && left && !err)
2141 err = proc_put_char(&buffer, &left, '\n');
2142 if (write && !err && left)
2143 left -= proc_skip_spaces(&kbuf);
2148 return err ? : -EINVAL;
2156 static int do_proc_dointvec(struct ctl_table *table, int write,
2157 void __user *buffer, size_t *lenp, loff_t *ppos,
2158 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2159 int write, void *data),
2162 return __do_proc_dointvec(table->data, table, write,
2163 buffer, lenp, ppos, conv, data);
2167 * proc_dointvec - read a vector of integers
2168 * @table: the sysctl table
2169 * @write: %TRUE if this is a write to the sysctl file
2170 * @buffer: the user buffer
2171 * @lenp: the size of the user buffer
2172 * @ppos: file position
2174 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2175 * values from/to the user buffer, treated as an ASCII string.
2177 * Returns 0 on success.
2179 int proc_dointvec(struct ctl_table *table, int write,
2180 void __user *buffer, size_t *lenp, loff_t *ppos)
2182 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2187 * Taint values can only be increased
2188 * This means we can safely use a temporary.
2190 static int proc_taint(struct ctl_table *table, int write,
2191 void __user *buffer, size_t *lenp, loff_t *ppos)
2194 unsigned long tmptaint = get_taint();
2197 if (write && !capable(CAP_SYS_ADMIN))
2202 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2208 * Poor man's atomic or. Not worth adding a primitive
2209 * to everyone's atomic.h for this
2212 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2213 if ((tmptaint >> i) & 1)
2214 add_taint(i, LOCKDEP_STILL_OK);
2221 #ifdef CONFIG_PRINTK
2222 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2223 void __user *buffer, size_t *lenp, loff_t *ppos)
2225 if (write && !capable(CAP_SYS_ADMIN))
2228 return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2232 struct do_proc_dointvec_minmax_conv_param {
2237 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2239 int write, void *data)
2241 struct do_proc_dointvec_minmax_conv_param *param = data;
2243 int val = *negp ? -*lvalp : *lvalp;
2244 if ((param->min && *param->min > val) ||
2245 (param->max && *param->max < val))
2252 *lvalp = -(unsigned long)val;
2255 *lvalp = (unsigned long)val;
2262 * proc_dointvec_minmax - read a vector of integers with min/max values
2263 * @table: the sysctl table
2264 * @write: %TRUE if this is a write to the sysctl file
2265 * @buffer: the user buffer
2266 * @lenp: the size of the user buffer
2267 * @ppos: file position
2269 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2270 * values from/to the user buffer, treated as an ASCII string.
2272 * This routine will ensure the values are within the range specified by
2273 * table->extra1 (min) and table->extra2 (max).
2275 * Returns 0 on success.
2277 int proc_dointvec_minmax(struct ctl_table *table, int write,
2278 void __user *buffer, size_t *lenp, loff_t *ppos)
2280 struct do_proc_dointvec_minmax_conv_param param = {
2281 .min = (int *) table->extra1,
2282 .max = (int *) table->extra2,
2284 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2285 do_proc_dointvec_minmax_conv, ¶m);
2288 static void validate_coredump_safety(void)
2290 #ifdef CONFIG_COREDUMP
2291 if (suid_dumpable == SUID_DUMP_ROOT &&
2292 core_pattern[0] != '/' && core_pattern[0] != '|') {
2293 printk(KERN_WARNING "Unsafe core_pattern used with "\
2294 "suid_dumpable=2. Pipe handler or fully qualified "\
2295 "core dump path required.\n");
2300 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2301 void __user *buffer, size_t *lenp, loff_t *ppos)
2303 int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2305 validate_coredump_safety();
2309 #ifdef CONFIG_COREDUMP
2310 static int proc_dostring_coredump(struct ctl_table *table, int write,
2311 void __user *buffer, size_t *lenp, loff_t *ppos)
2313 int error = proc_dostring(table, write, buffer, lenp, ppos);
2315 validate_coredump_safety();
2320 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2321 void __user *buffer,
2322 size_t *lenp, loff_t *ppos,
2323 unsigned long convmul,
2324 unsigned long convdiv)
2326 unsigned long *i, *min, *max;
2327 int vleft, first = 1, err = 0;
2328 unsigned long page = 0;
2332 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2337 i = (unsigned long *) data;
2338 min = (unsigned long *) table->extra1;
2339 max = (unsigned long *) table->extra2;
2340 vleft = table->maxlen / sizeof(unsigned long);
2345 switch (sysctl_writes_strict) {
2346 case SYSCTL_WRITES_STRICT:
2348 case SYSCTL_WRITES_WARN:
2349 warn_sysctl_write(table);
2356 if (left > PAGE_SIZE - 1)
2357 left = PAGE_SIZE - 1;
2358 page = __get_free_page(GFP_TEMPORARY);
2359 kbuf = (char *) page;
2362 if (copy_from_user(kbuf, buffer, left)) {
2369 for (; left && vleft--; i++, first = 0) {
2375 left -= proc_skip_spaces(&kbuf);
2377 err = proc_get_long(&kbuf, &left, &val, &neg,
2379 sizeof(proc_wspace_sep), NULL);
2384 if ((min && val < *min) || (max && val > *max))
2388 val = convdiv * (*i) / convmul;
2390 err = proc_put_char(&buffer, &left, '\t');
2394 err = proc_put_long(&buffer, &left, val, false);
2400 if (!write && !first && left && !err)
2401 err = proc_put_char(&buffer, &left, '\n');
2403 left -= proc_skip_spaces(&kbuf);
2408 return err ? : -EINVAL;
2416 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2417 void __user *buffer,
2418 size_t *lenp, loff_t *ppos,
2419 unsigned long convmul,
2420 unsigned long convdiv)
2422 return __do_proc_doulongvec_minmax(table->data, table, write,
2423 buffer, lenp, ppos, convmul, convdiv);
2427 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2428 * @table: the sysctl table
2429 * @write: %TRUE if this is a write to the sysctl file
2430 * @buffer: the user buffer
2431 * @lenp: the size of the user buffer
2432 * @ppos: file position
2434 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2435 * values from/to the user buffer, treated as an ASCII string.
2437 * This routine will ensure the values are within the range specified by
2438 * table->extra1 (min) and table->extra2 (max).
2440 * Returns 0 on success.
2442 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2443 void __user *buffer, size_t *lenp, loff_t *ppos)
2445 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2449 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2450 * @table: the sysctl table
2451 * @write: %TRUE if this is a write to the sysctl file
2452 * @buffer: the user buffer
2453 * @lenp: the size of the user buffer
2454 * @ppos: file position
2456 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2457 * values from/to the user buffer, treated as an ASCII string. The values
2458 * are treated as milliseconds, and converted to jiffies when they are stored.
2460 * This routine will ensure the values are within the range specified by
2461 * table->extra1 (min) and table->extra2 (max).
2463 * Returns 0 on success.
2465 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2466 void __user *buffer,
2467 size_t *lenp, loff_t *ppos)
2469 return do_proc_doulongvec_minmax(table, write, buffer,
2470 lenp, ppos, HZ, 1000l);
2474 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2476 int write, void *data)
2479 if (*lvalp > LONG_MAX / HZ)
2481 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2487 lval = -(unsigned long)val;
2490 lval = (unsigned long)val;
2497 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2499 int write, void *data)
2502 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2504 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2510 lval = -(unsigned long)val;
2513 lval = (unsigned long)val;
2515 *lvalp = jiffies_to_clock_t(lval);
2520 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2522 int write, void *data)
2525 unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2535 lval = -(unsigned long)val;
2538 lval = (unsigned long)val;
2540 *lvalp = jiffies_to_msecs(lval);
2546 * proc_dointvec_jiffies - read a vector of integers as seconds
2547 * @table: the sysctl table
2548 * @write: %TRUE if this is a write to the sysctl file
2549 * @buffer: the user buffer
2550 * @lenp: the size of the user buffer
2551 * @ppos: file position
2553 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2554 * values from/to the user buffer, treated as an ASCII string.
2555 * The values read are assumed to be in seconds, and are converted into
2558 * Returns 0 on success.
2560 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2561 void __user *buffer, size_t *lenp, loff_t *ppos)
2563 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2564 do_proc_dointvec_jiffies_conv,NULL);
2568 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2569 * @table: the sysctl table
2570 * @write: %TRUE if this is a write to the sysctl file
2571 * @buffer: the user buffer
2572 * @lenp: the size of the user buffer
2573 * @ppos: pointer to the file position
2575 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2576 * values from/to the user buffer, treated as an ASCII string.
2577 * The values read are assumed to be in 1/USER_HZ seconds, and
2578 * are converted into jiffies.
2580 * Returns 0 on success.
2582 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2583 void __user *buffer, size_t *lenp, loff_t *ppos)
2585 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2586 do_proc_dointvec_userhz_jiffies_conv,NULL);
2590 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2591 * @table: the sysctl table
2592 * @write: %TRUE if this is a write to the sysctl file
2593 * @buffer: the user buffer
2594 * @lenp: the size of the user buffer
2595 * @ppos: file position
2596 * @ppos: the current position in the file
2598 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2599 * values from/to the user buffer, treated as an ASCII string.
2600 * The values read are assumed to be in 1/1000 seconds, and
2601 * are converted into jiffies.
2603 * Returns 0 on success.
2605 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2606 void __user *buffer, size_t *lenp, loff_t *ppos)
2608 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2609 do_proc_dointvec_ms_jiffies_conv, NULL);
2612 static int proc_do_cad_pid(struct ctl_table *table, int write,
2613 void __user *buffer, size_t *lenp, loff_t *ppos)
2615 struct pid *new_pid;
2619 tmp = pid_vnr(cad_pid);
2621 r = __do_proc_dointvec(&tmp, table, write, buffer,
2622 lenp, ppos, NULL, NULL);
2626 new_pid = find_get_pid(tmp);
2630 put_pid(xchg(&cad_pid, new_pid));
2635 * proc_do_large_bitmap - read/write from/to a large bitmap
2636 * @table: the sysctl table
2637 * @write: %TRUE if this is a write to the sysctl file
2638 * @buffer: the user buffer
2639 * @lenp: the size of the user buffer
2640 * @ppos: file position
2642 * The bitmap is stored at table->data and the bitmap length (in bits)
2645 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2646 * large bitmaps may be represented in a compact manner. Writing into
2647 * the file will clear the bitmap then update it with the given input.
2649 * Returns 0 on success.
2651 int proc_do_large_bitmap(struct ctl_table *table, int write,
2652 void __user *buffer, size_t *lenp, loff_t *ppos)
2656 size_t left = *lenp;
2657 unsigned long bitmap_len = table->maxlen;
2658 unsigned long *bitmap = *(unsigned long **) table->data;
2659 unsigned long *tmp_bitmap = NULL;
2660 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2662 if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
2668 unsigned long page = 0;
2671 if (left > PAGE_SIZE - 1)
2672 left = PAGE_SIZE - 1;
2674 page = __get_free_page(GFP_TEMPORARY);
2675 kbuf = (char *) page;
2678 if (copy_from_user(kbuf, buffer, left)) {
2684 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2690 proc_skip_char(&kbuf, &left, '\n');
2691 while (!err && left) {
2692 unsigned long val_a, val_b;
2695 err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2699 if (val_a >= bitmap_len || neg) {
2711 err = proc_get_long(&kbuf, &left, &val_b,
2712 &neg, tr_b, sizeof(tr_b),
2716 if (val_b >= bitmap_len || neg ||
2727 bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
2729 proc_skip_char(&kbuf, &left, '\n');
2733 unsigned long bit_a, bit_b = 0;
2736 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2737 if (bit_a >= bitmap_len)
2739 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2743 err = proc_put_char(&buffer, &left, ',');
2747 err = proc_put_long(&buffer, &left, bit_a, false);
2750 if (bit_a != bit_b) {
2751 err = proc_put_char(&buffer, &left, '-');
2754 err = proc_put_long(&buffer, &left, bit_b, false);
2762 err = proc_put_char(&buffer, &left, '\n');
2768 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2770 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
2782 #else /* CONFIG_PROC_SYSCTL */
2784 int proc_dostring(struct ctl_table *table, int write,
2785 void __user *buffer, size_t *lenp, loff_t *ppos)
2790 int proc_dointvec(struct ctl_table *table, int write,
2791 void __user *buffer, size_t *lenp, loff_t *ppos)
2796 int proc_dointvec_minmax(struct ctl_table *table, int write,
2797 void __user *buffer, size_t *lenp, loff_t *ppos)
2802 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2803 void __user *buffer, size_t *lenp, loff_t *ppos)
2808 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2809 void __user *buffer, size_t *lenp, loff_t *ppos)
2814 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2815 void __user *buffer, size_t *lenp, loff_t *ppos)
2820 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2821 void __user *buffer, size_t *lenp, loff_t *ppos)
2826 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2827 void __user *buffer,
2828 size_t *lenp, loff_t *ppos)
2834 #endif /* CONFIG_PROC_SYSCTL */
2837 * No sense putting this after each symbol definition, twice,
2838 * exception granted :-)
2840 EXPORT_SYMBOL(proc_dointvec);
2841 EXPORT_SYMBOL(proc_dointvec_jiffies);
2842 EXPORT_SYMBOL(proc_dointvec_minmax);
2843 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2844 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2845 EXPORT_SYMBOL(proc_dostring);
2846 EXPORT_SYMBOL(proc_doulongvec_minmax);
2847 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);