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_STRICT;
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 #ifdef CONFIG_SCHEDSTATS
355 .procname = "sched_schedstats",
357 .maxlen = sizeof(unsigned int),
359 .proc_handler = sysctl_schedstats,
363 #endif /* CONFIG_SCHEDSTATS */
364 #endif /* CONFIG_SMP */
365 #ifdef CONFIG_NUMA_BALANCING
367 .procname = "numa_balancing_scan_delay_ms",
368 .data = &sysctl_numa_balancing_scan_delay,
369 .maxlen = sizeof(unsigned int),
371 .proc_handler = proc_dointvec,
374 .procname = "numa_balancing_scan_period_min_ms",
375 .data = &sysctl_numa_balancing_scan_period_min,
376 .maxlen = sizeof(unsigned int),
378 .proc_handler = proc_dointvec,
381 .procname = "numa_balancing_scan_period_max_ms",
382 .data = &sysctl_numa_balancing_scan_period_max,
383 .maxlen = sizeof(unsigned int),
385 .proc_handler = proc_dointvec,
388 .procname = "numa_balancing_scan_size_mb",
389 .data = &sysctl_numa_balancing_scan_size,
390 .maxlen = sizeof(unsigned int),
392 .proc_handler = proc_dointvec_minmax,
396 .procname = "numa_balancing",
397 .data = NULL, /* filled in by handler */
398 .maxlen = sizeof(unsigned int),
400 .proc_handler = sysctl_numa_balancing,
404 #endif /* CONFIG_NUMA_BALANCING */
405 #endif /* CONFIG_SCHED_DEBUG */
407 .procname = "sched_rt_period_us",
408 .data = &sysctl_sched_rt_period,
409 .maxlen = sizeof(unsigned int),
411 .proc_handler = sched_rt_handler,
414 .procname = "sched_rt_runtime_us",
415 .data = &sysctl_sched_rt_runtime,
416 .maxlen = sizeof(int),
418 .proc_handler = sched_rt_handler,
421 .procname = "sched_rr_timeslice_ms",
422 .data = &sched_rr_timeslice,
423 .maxlen = sizeof(int),
425 .proc_handler = sched_rr_handler,
427 #ifdef CONFIG_SCHED_AUTOGROUP
429 .procname = "sched_autogroup_enabled",
430 .data = &sysctl_sched_autogroup_enabled,
431 .maxlen = sizeof(unsigned int),
433 .proc_handler = proc_dointvec_minmax,
438 #ifdef CONFIG_CFS_BANDWIDTH
440 .procname = "sched_cfs_bandwidth_slice_us",
441 .data = &sysctl_sched_cfs_bandwidth_slice,
442 .maxlen = sizeof(unsigned int),
444 .proc_handler = proc_dointvec_minmax,
448 #ifdef CONFIG_PROVE_LOCKING
450 .procname = "prove_locking",
451 .data = &prove_locking,
452 .maxlen = sizeof(int),
454 .proc_handler = proc_dointvec,
457 #ifdef CONFIG_LOCK_STAT
459 .procname = "lock_stat",
461 .maxlen = sizeof(int),
463 .proc_handler = proc_dointvec,
468 .data = &panic_timeout,
469 .maxlen = sizeof(int),
471 .proc_handler = proc_dointvec,
473 #ifdef CONFIG_COREDUMP
475 .procname = "core_uses_pid",
476 .data = &core_uses_pid,
477 .maxlen = sizeof(int),
479 .proc_handler = proc_dointvec,
482 .procname = "core_pattern",
483 .data = core_pattern,
484 .maxlen = CORENAME_MAX_SIZE,
486 .proc_handler = proc_dostring_coredump,
489 .procname = "core_pipe_limit",
490 .data = &core_pipe_limit,
491 .maxlen = sizeof(unsigned int),
493 .proc_handler = proc_dointvec,
496 #ifdef CONFIG_PROC_SYSCTL
498 .procname = "tainted",
499 .maxlen = sizeof(long),
501 .proc_handler = proc_taint,
504 .procname = "sysctl_writes_strict",
505 .data = &sysctl_writes_strict,
506 .maxlen = sizeof(int),
508 .proc_handler = proc_dointvec_minmax,
513 #ifdef CONFIG_LATENCYTOP
515 .procname = "latencytop",
516 .data = &latencytop_enabled,
517 .maxlen = sizeof(int),
519 .proc_handler = sysctl_latencytop,
522 #ifdef CONFIG_BLK_DEV_INITRD
524 .procname = "real-root-dev",
525 .data = &real_root_dev,
526 .maxlen = sizeof(int),
528 .proc_handler = proc_dointvec,
532 .procname = "print-fatal-signals",
533 .data = &print_fatal_signals,
534 .maxlen = sizeof(int),
536 .proc_handler = proc_dointvec,
540 .procname = "reboot-cmd",
541 .data = reboot_command,
544 .proc_handler = proc_dostring,
547 .procname = "stop-a",
548 .data = &stop_a_enabled,
549 .maxlen = sizeof (int),
551 .proc_handler = proc_dointvec,
554 .procname = "scons-poweroff",
555 .data = &scons_pwroff,
556 .maxlen = sizeof (int),
558 .proc_handler = proc_dointvec,
561 #ifdef CONFIG_SPARC64
563 .procname = "tsb-ratio",
564 .data = &sysctl_tsb_ratio,
565 .maxlen = sizeof (int),
567 .proc_handler = proc_dointvec,
572 .procname = "soft-power",
573 .data = &pwrsw_enabled,
574 .maxlen = sizeof (int),
576 .proc_handler = proc_dointvec,
579 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
581 .procname = "unaligned-trap",
582 .data = &unaligned_enabled,
583 .maxlen = sizeof (int),
585 .proc_handler = proc_dointvec,
589 .procname = "ctrl-alt-del",
591 .maxlen = sizeof(int),
593 .proc_handler = proc_dointvec,
595 #ifdef CONFIG_FUNCTION_TRACER
597 .procname = "ftrace_enabled",
598 .data = &ftrace_enabled,
599 .maxlen = sizeof(int),
601 .proc_handler = ftrace_enable_sysctl,
604 #ifdef CONFIG_STACK_TRACER
606 .procname = "stack_tracer_enabled",
607 .data = &stack_tracer_enabled,
608 .maxlen = sizeof(int),
610 .proc_handler = stack_trace_sysctl,
613 #ifdef CONFIG_TRACING
615 .procname = "ftrace_dump_on_oops",
616 .data = &ftrace_dump_on_oops,
617 .maxlen = sizeof(int),
619 .proc_handler = proc_dointvec,
622 .procname = "traceoff_on_warning",
623 .data = &__disable_trace_on_warning,
624 .maxlen = sizeof(__disable_trace_on_warning),
626 .proc_handler = proc_dointvec,
629 .procname = "tracepoint_printk",
630 .data = &tracepoint_printk,
631 .maxlen = sizeof(tracepoint_printk),
633 .proc_handler = proc_dointvec,
636 #ifdef CONFIG_KEXEC_CORE
638 .procname = "kexec_load_disabled",
639 .data = &kexec_load_disabled,
640 .maxlen = sizeof(int),
642 /* only handle a transition from default "0" to "1" */
643 .proc_handler = proc_dointvec_minmax,
648 #ifdef CONFIG_MODULES
650 .procname = "modprobe",
651 .data = &modprobe_path,
652 .maxlen = KMOD_PATH_LEN,
654 .proc_handler = proc_dostring,
657 .procname = "modules_disabled",
658 .data = &modules_disabled,
659 .maxlen = sizeof(int),
661 /* only handle a transition from default "0" to "1" */
662 .proc_handler = proc_dointvec_minmax,
667 #ifdef CONFIG_UEVENT_HELPER
669 .procname = "hotplug",
670 .data = &uevent_helper,
671 .maxlen = UEVENT_HELPER_PATH_LEN,
673 .proc_handler = proc_dostring,
676 #ifdef CONFIG_CHR_DEV_SG
678 .procname = "sg-big-buff",
679 .data = &sg_big_buff,
680 .maxlen = sizeof (int),
682 .proc_handler = proc_dointvec,
685 #ifdef CONFIG_BSD_PROCESS_ACCT
689 .maxlen = 3*sizeof(int),
691 .proc_handler = proc_dointvec,
694 #ifdef CONFIG_MAGIC_SYSRQ
697 .data = &__sysrq_enabled,
698 .maxlen = sizeof (int),
700 .proc_handler = sysrq_sysctl_handler,
703 #ifdef CONFIG_PROC_SYSCTL
705 .procname = "cad_pid",
707 .maxlen = sizeof (int),
709 .proc_handler = proc_do_cad_pid,
713 .procname = "threads-max",
715 .maxlen = sizeof(int),
717 .proc_handler = sysctl_max_threads,
720 .procname = "random",
722 .child = random_table,
725 .procname = "usermodehelper",
727 .child = usermodehelper_table,
730 .procname = "overflowuid",
731 .data = &overflowuid,
732 .maxlen = sizeof(int),
734 .proc_handler = proc_dointvec_minmax,
735 .extra1 = &minolduid,
736 .extra2 = &maxolduid,
739 .procname = "overflowgid",
740 .data = &overflowgid,
741 .maxlen = sizeof(int),
743 .proc_handler = proc_dointvec_minmax,
744 .extra1 = &minolduid,
745 .extra2 = &maxolduid,
748 #ifdef CONFIG_MATHEMU
750 .procname = "ieee_emulation_warnings",
751 .data = &sysctl_ieee_emulation_warnings,
752 .maxlen = sizeof(int),
754 .proc_handler = proc_dointvec,
758 .procname = "userprocess_debug",
759 .data = &show_unhandled_signals,
760 .maxlen = sizeof(int),
762 .proc_handler = proc_dointvec,
766 .procname = "pid_max",
768 .maxlen = sizeof (int),
770 .proc_handler = proc_dointvec_minmax,
771 .extra1 = &pid_max_min,
772 .extra2 = &pid_max_max,
775 .procname = "panic_on_oops",
776 .data = &panic_on_oops,
777 .maxlen = sizeof(int),
779 .proc_handler = proc_dointvec,
781 #if defined CONFIG_PRINTK
783 .procname = "printk",
784 .data = &console_loglevel,
785 .maxlen = 4*sizeof(int),
787 .proc_handler = proc_dointvec,
790 .procname = "printk_ratelimit",
791 .data = &printk_ratelimit_state.interval,
792 .maxlen = sizeof(int),
794 .proc_handler = proc_dointvec_jiffies,
797 .procname = "printk_ratelimit_burst",
798 .data = &printk_ratelimit_state.burst,
799 .maxlen = sizeof(int),
801 .proc_handler = proc_dointvec,
804 .procname = "printk_delay",
805 .data = &printk_delay_msec,
806 .maxlen = sizeof(int),
808 .proc_handler = proc_dointvec_minmax,
810 .extra2 = &ten_thousand,
813 .procname = "dmesg_restrict",
814 .data = &dmesg_restrict,
815 .maxlen = sizeof(int),
817 .proc_handler = proc_dointvec_minmax_sysadmin,
822 .procname = "kptr_restrict",
823 .data = &kptr_restrict,
824 .maxlen = sizeof(int),
826 .proc_handler = proc_dointvec_minmax_sysadmin,
832 .procname = "ngroups_max",
833 .data = &ngroups_max,
834 .maxlen = sizeof (int),
836 .proc_handler = proc_dointvec,
839 .procname = "cap_last_cap",
840 .data = (void *)&cap_last_cap,
841 .maxlen = sizeof(int),
843 .proc_handler = proc_dointvec,
845 #if defined(CONFIG_LOCKUP_DETECTOR)
847 .procname = "watchdog",
848 .data = &watchdog_user_enabled,
849 .maxlen = sizeof (int),
851 .proc_handler = proc_watchdog,
856 .procname = "watchdog_thresh",
857 .data = &watchdog_thresh,
858 .maxlen = sizeof(int),
860 .proc_handler = proc_watchdog_thresh,
865 .procname = "nmi_watchdog",
866 .data = &nmi_watchdog_enabled,
867 .maxlen = sizeof (int),
869 .proc_handler = proc_nmi_watchdog,
871 #if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)
878 .procname = "soft_watchdog",
879 .data = &soft_watchdog_enabled,
880 .maxlen = sizeof (int),
882 .proc_handler = proc_soft_watchdog,
887 .procname = "watchdog_cpumask",
888 .data = &watchdog_cpumask_bits,
891 .proc_handler = proc_watchdog_cpumask,
894 .procname = "softlockup_panic",
895 .data = &softlockup_panic,
896 .maxlen = sizeof(int),
898 .proc_handler = proc_dointvec_minmax,
902 #ifdef CONFIG_HARDLOCKUP_DETECTOR
904 .procname = "hardlockup_panic",
905 .data = &hardlockup_panic,
906 .maxlen = sizeof(int),
908 .proc_handler = proc_dointvec_minmax,
915 .procname = "softlockup_all_cpu_backtrace",
916 .data = &sysctl_softlockup_all_cpu_backtrace,
917 .maxlen = sizeof(int),
919 .proc_handler = proc_dointvec_minmax,
924 .procname = "hardlockup_all_cpu_backtrace",
925 .data = &sysctl_hardlockup_all_cpu_backtrace,
926 .maxlen = sizeof(int),
928 .proc_handler = proc_dointvec_minmax,
932 #endif /* CONFIG_SMP */
934 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
936 .procname = "unknown_nmi_panic",
937 .data = &unknown_nmi_panic,
938 .maxlen = sizeof (int),
940 .proc_handler = proc_dointvec,
943 #if defined(CONFIG_X86)
945 .procname = "panic_on_unrecovered_nmi",
946 .data = &panic_on_unrecovered_nmi,
947 .maxlen = sizeof(int),
949 .proc_handler = proc_dointvec,
952 .procname = "panic_on_io_nmi",
953 .data = &panic_on_io_nmi,
954 .maxlen = sizeof(int),
956 .proc_handler = proc_dointvec,
958 #ifdef CONFIG_DEBUG_STACKOVERFLOW
960 .procname = "panic_on_stackoverflow",
961 .data = &sysctl_panic_on_stackoverflow,
962 .maxlen = sizeof(int),
964 .proc_handler = proc_dointvec,
968 .procname = "bootloader_type",
969 .data = &bootloader_type,
970 .maxlen = sizeof (int),
972 .proc_handler = proc_dointvec,
975 .procname = "bootloader_version",
976 .data = &bootloader_version,
977 .maxlen = sizeof (int),
979 .proc_handler = proc_dointvec,
982 .procname = "kstack_depth_to_print",
983 .data = &kstack_depth_to_print,
984 .maxlen = sizeof(int),
986 .proc_handler = proc_dointvec,
989 .procname = "io_delay_type",
990 .data = &io_delay_type,
991 .maxlen = sizeof(int),
993 .proc_handler = proc_dointvec,
996 #if defined(CONFIG_MMU)
998 .procname = "randomize_va_space",
999 .data = &randomize_va_space,
1000 .maxlen = sizeof(int),
1002 .proc_handler = proc_dointvec,
1005 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1007 .procname = "spin_retry",
1008 .data = &spin_retry,
1009 .maxlen = sizeof (int),
1011 .proc_handler = proc_dointvec,
1014 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1016 .procname = "acpi_video_flags",
1017 .data = &acpi_realmode_flags,
1018 .maxlen = sizeof (unsigned long),
1020 .proc_handler = proc_doulongvec_minmax,
1023 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1025 .procname = "ignore-unaligned-usertrap",
1026 .data = &no_unaligned_warning,
1027 .maxlen = sizeof (int),
1029 .proc_handler = proc_dointvec,
1034 .procname = "unaligned-dump-stack",
1035 .data = &unaligned_dump_stack,
1036 .maxlen = sizeof (int),
1038 .proc_handler = proc_dointvec,
1041 #ifdef CONFIG_DETECT_HUNG_TASK
1043 .procname = "hung_task_panic",
1044 .data = &sysctl_hung_task_panic,
1045 .maxlen = sizeof(int),
1047 .proc_handler = proc_dointvec_minmax,
1052 .procname = "hung_task_check_count",
1053 .data = &sysctl_hung_task_check_count,
1054 .maxlen = sizeof(int),
1056 .proc_handler = proc_dointvec_minmax,
1060 .procname = "hung_task_timeout_secs",
1061 .data = &sysctl_hung_task_timeout_secs,
1062 .maxlen = sizeof(unsigned long),
1064 .proc_handler = proc_dohung_task_timeout_secs,
1065 .extra2 = &hung_task_timeout_max,
1068 .procname = "hung_task_warnings",
1069 .data = &sysctl_hung_task_warnings,
1070 .maxlen = sizeof(int),
1072 .proc_handler = proc_dointvec_minmax,
1076 #ifdef CONFIG_COMPAT
1078 .procname = "compat-log",
1079 .data = &compat_log,
1080 .maxlen = sizeof (int),
1082 .proc_handler = proc_dointvec,
1085 #ifdef CONFIG_RT_MUTEXES
1087 .procname = "max_lock_depth",
1088 .data = &max_lock_depth,
1089 .maxlen = sizeof(int),
1091 .proc_handler = proc_dointvec,
1095 .procname = "poweroff_cmd",
1096 .data = &poweroff_cmd,
1097 .maxlen = POWEROFF_CMD_PATH_LEN,
1099 .proc_handler = proc_dostring,
1105 .child = key_sysctls,
1108 #ifdef CONFIG_PERF_EVENTS
1110 * User-space scripts rely on the existence of this file
1111 * as a feature check for perf_events being enabled.
1113 * So it's an ABI, do not remove!
1116 .procname = "perf_event_paranoid",
1117 .data = &sysctl_perf_event_paranoid,
1118 .maxlen = sizeof(sysctl_perf_event_paranoid),
1120 .proc_handler = proc_dointvec,
1123 .procname = "perf_event_mlock_kb",
1124 .data = &sysctl_perf_event_mlock,
1125 .maxlen = sizeof(sysctl_perf_event_mlock),
1127 .proc_handler = proc_dointvec,
1130 .procname = "perf_event_max_sample_rate",
1131 .data = &sysctl_perf_event_sample_rate,
1132 .maxlen = sizeof(sysctl_perf_event_sample_rate),
1134 .proc_handler = perf_proc_update_handler,
1138 .procname = "perf_cpu_time_max_percent",
1139 .data = &sysctl_perf_cpu_time_max_percent,
1140 .maxlen = sizeof(sysctl_perf_cpu_time_max_percent),
1142 .proc_handler = perf_cpu_time_max_percent_handler,
1144 .extra2 = &one_hundred,
1147 #ifdef CONFIG_KMEMCHECK
1149 .procname = "kmemcheck",
1150 .data = &kmemcheck_enabled,
1151 .maxlen = sizeof(int),
1153 .proc_handler = proc_dointvec,
1157 .procname = "panic_on_warn",
1158 .data = &panic_on_warn,
1159 .maxlen = sizeof(int),
1161 .proc_handler = proc_dointvec_minmax,
1165 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1167 .procname = "timer_migration",
1168 .data = &sysctl_timer_migration,
1169 .maxlen = sizeof(unsigned int),
1171 .proc_handler = timer_migration_handler,
1174 #ifdef CONFIG_BPF_SYSCALL
1176 .procname = "unprivileged_bpf_disabled",
1177 .data = &sysctl_unprivileged_bpf_disabled,
1178 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled),
1180 /* only handle a transition from default "0" to "1" */
1181 .proc_handler = proc_dointvec_minmax,
1189 static struct ctl_table vm_table[] = {
1191 .procname = "overcommit_memory",
1192 .data = &sysctl_overcommit_memory,
1193 .maxlen = sizeof(sysctl_overcommit_memory),
1195 .proc_handler = proc_dointvec_minmax,
1200 .procname = "panic_on_oom",
1201 .data = &sysctl_panic_on_oom,
1202 .maxlen = sizeof(sysctl_panic_on_oom),
1204 .proc_handler = proc_dointvec_minmax,
1209 .procname = "oom_kill_allocating_task",
1210 .data = &sysctl_oom_kill_allocating_task,
1211 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1213 .proc_handler = proc_dointvec,
1216 .procname = "oom_dump_tasks",
1217 .data = &sysctl_oom_dump_tasks,
1218 .maxlen = sizeof(sysctl_oom_dump_tasks),
1220 .proc_handler = proc_dointvec,
1223 .procname = "overcommit_ratio",
1224 .data = &sysctl_overcommit_ratio,
1225 .maxlen = sizeof(sysctl_overcommit_ratio),
1227 .proc_handler = overcommit_ratio_handler,
1230 .procname = "overcommit_kbytes",
1231 .data = &sysctl_overcommit_kbytes,
1232 .maxlen = sizeof(sysctl_overcommit_kbytes),
1234 .proc_handler = overcommit_kbytes_handler,
1237 .procname = "page-cluster",
1238 .data = &page_cluster,
1239 .maxlen = sizeof(int),
1241 .proc_handler = proc_dointvec_minmax,
1245 .procname = "dirty_background_ratio",
1246 .data = &dirty_background_ratio,
1247 .maxlen = sizeof(dirty_background_ratio),
1249 .proc_handler = dirty_background_ratio_handler,
1251 .extra2 = &one_hundred,
1254 .procname = "dirty_background_bytes",
1255 .data = &dirty_background_bytes,
1256 .maxlen = sizeof(dirty_background_bytes),
1258 .proc_handler = dirty_background_bytes_handler,
1262 .procname = "dirty_ratio",
1263 .data = &vm_dirty_ratio,
1264 .maxlen = sizeof(vm_dirty_ratio),
1266 .proc_handler = dirty_ratio_handler,
1268 .extra2 = &one_hundred,
1271 .procname = "dirty_bytes",
1272 .data = &vm_dirty_bytes,
1273 .maxlen = sizeof(vm_dirty_bytes),
1275 .proc_handler = dirty_bytes_handler,
1276 .extra1 = &dirty_bytes_min,
1279 .procname = "dirty_writeback_centisecs",
1280 .data = &dirty_writeback_interval,
1281 .maxlen = sizeof(dirty_writeback_interval),
1283 .proc_handler = dirty_writeback_centisecs_handler,
1286 .procname = "dirty_expire_centisecs",
1287 .data = &dirty_expire_interval,
1288 .maxlen = sizeof(dirty_expire_interval),
1290 .proc_handler = proc_dointvec_minmax,
1294 .procname = "dirtytime_expire_seconds",
1295 .data = &dirtytime_expire_interval,
1296 .maxlen = sizeof(dirty_expire_interval),
1298 .proc_handler = dirtytime_interval_handler,
1302 .procname = "nr_pdflush_threads",
1303 .mode = 0444 /* read-only */,
1304 .proc_handler = pdflush_proc_obsolete,
1307 .procname = "swappiness",
1308 .data = &vm_swappiness,
1309 .maxlen = sizeof(vm_swappiness),
1311 .proc_handler = proc_dointvec_minmax,
1313 .extra2 = &one_hundred,
1315 #ifdef CONFIG_HUGETLB_PAGE
1317 .procname = "nr_hugepages",
1319 .maxlen = sizeof(unsigned long),
1321 .proc_handler = hugetlb_sysctl_handler,
1325 .procname = "nr_hugepages_mempolicy",
1327 .maxlen = sizeof(unsigned long),
1329 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1333 .procname = "hugetlb_shm_group",
1334 .data = &sysctl_hugetlb_shm_group,
1335 .maxlen = sizeof(gid_t),
1337 .proc_handler = proc_dointvec,
1340 .procname = "hugepages_treat_as_movable",
1341 .data = &hugepages_treat_as_movable,
1342 .maxlen = sizeof(int),
1344 .proc_handler = proc_dointvec,
1347 .procname = "nr_overcommit_hugepages",
1349 .maxlen = sizeof(unsigned long),
1351 .proc_handler = hugetlb_overcommit_handler,
1355 .procname = "lowmem_reserve_ratio",
1356 .data = &sysctl_lowmem_reserve_ratio,
1357 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1359 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1362 .procname = "drop_caches",
1363 .data = &sysctl_drop_caches,
1364 .maxlen = sizeof(int),
1366 .proc_handler = drop_caches_sysctl_handler,
1370 #ifdef CONFIG_COMPACTION
1372 .procname = "compact_memory",
1373 .data = &sysctl_compact_memory,
1374 .maxlen = sizeof(int),
1376 .proc_handler = sysctl_compaction_handler,
1379 .procname = "extfrag_threshold",
1380 .data = &sysctl_extfrag_threshold,
1381 .maxlen = sizeof(int),
1383 .proc_handler = sysctl_extfrag_handler,
1384 .extra1 = &min_extfrag_threshold,
1385 .extra2 = &max_extfrag_threshold,
1388 .procname = "compact_unevictable_allowed",
1389 .data = &sysctl_compact_unevictable_allowed,
1390 .maxlen = sizeof(int),
1392 .proc_handler = proc_dointvec,
1397 #endif /* CONFIG_COMPACTION */
1399 .procname = "min_free_kbytes",
1400 .data = &min_free_kbytes,
1401 .maxlen = sizeof(min_free_kbytes),
1403 .proc_handler = min_free_kbytes_sysctl_handler,
1407 .procname = "percpu_pagelist_fraction",
1408 .data = &percpu_pagelist_fraction,
1409 .maxlen = sizeof(percpu_pagelist_fraction),
1411 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1416 .procname = "max_map_count",
1417 .data = &sysctl_max_map_count,
1418 .maxlen = sizeof(sysctl_max_map_count),
1420 .proc_handler = proc_dointvec_minmax,
1425 .procname = "nr_trim_pages",
1426 .data = &sysctl_nr_trim_pages,
1427 .maxlen = sizeof(sysctl_nr_trim_pages),
1429 .proc_handler = proc_dointvec_minmax,
1434 .procname = "laptop_mode",
1435 .data = &laptop_mode,
1436 .maxlen = sizeof(laptop_mode),
1438 .proc_handler = proc_dointvec_jiffies,
1441 .procname = "block_dump",
1442 .data = &block_dump,
1443 .maxlen = sizeof(block_dump),
1445 .proc_handler = proc_dointvec,
1449 .procname = "vfs_cache_pressure",
1450 .data = &sysctl_vfs_cache_pressure,
1451 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1453 .proc_handler = proc_dointvec,
1456 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1458 .procname = "legacy_va_layout",
1459 .data = &sysctl_legacy_va_layout,
1460 .maxlen = sizeof(sysctl_legacy_va_layout),
1462 .proc_handler = proc_dointvec,
1468 .procname = "zone_reclaim_mode",
1469 .data = &zone_reclaim_mode,
1470 .maxlen = sizeof(zone_reclaim_mode),
1472 .proc_handler = proc_dointvec,
1476 .procname = "min_unmapped_ratio",
1477 .data = &sysctl_min_unmapped_ratio,
1478 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1480 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1482 .extra2 = &one_hundred,
1485 .procname = "min_slab_ratio",
1486 .data = &sysctl_min_slab_ratio,
1487 .maxlen = sizeof(sysctl_min_slab_ratio),
1489 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1491 .extra2 = &one_hundred,
1496 .procname = "stat_interval",
1497 .data = &sysctl_stat_interval,
1498 .maxlen = sizeof(sysctl_stat_interval),
1500 .proc_handler = proc_dointvec_jiffies,
1505 .procname = "mmap_min_addr",
1506 .data = &dac_mmap_min_addr,
1507 .maxlen = sizeof(unsigned long),
1509 .proc_handler = mmap_min_addr_handler,
1514 .procname = "numa_zonelist_order",
1515 .data = &numa_zonelist_order,
1516 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1518 .proc_handler = numa_zonelist_order_handler,
1521 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1522 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1524 .procname = "vdso_enabled",
1525 #ifdef CONFIG_X86_32
1526 .data = &vdso32_enabled,
1527 .maxlen = sizeof(vdso32_enabled),
1529 .data = &vdso_enabled,
1530 .maxlen = sizeof(vdso_enabled),
1533 .proc_handler = proc_dointvec,
1537 #ifdef CONFIG_HIGHMEM
1539 .procname = "highmem_is_dirtyable",
1540 .data = &vm_highmem_is_dirtyable,
1541 .maxlen = sizeof(vm_highmem_is_dirtyable),
1543 .proc_handler = proc_dointvec_minmax,
1548 #ifdef CONFIG_MEMORY_FAILURE
1550 .procname = "memory_failure_early_kill",
1551 .data = &sysctl_memory_failure_early_kill,
1552 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1554 .proc_handler = proc_dointvec_minmax,
1559 .procname = "memory_failure_recovery",
1560 .data = &sysctl_memory_failure_recovery,
1561 .maxlen = sizeof(sysctl_memory_failure_recovery),
1563 .proc_handler = proc_dointvec_minmax,
1569 .procname = "user_reserve_kbytes",
1570 .data = &sysctl_user_reserve_kbytes,
1571 .maxlen = sizeof(sysctl_user_reserve_kbytes),
1573 .proc_handler = proc_doulongvec_minmax,
1576 .procname = "admin_reserve_kbytes",
1577 .data = &sysctl_admin_reserve_kbytes,
1578 .maxlen = sizeof(sysctl_admin_reserve_kbytes),
1580 .proc_handler = proc_doulongvec_minmax,
1582 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
1584 .procname = "mmap_rnd_bits",
1585 .data = &mmap_rnd_bits,
1586 .maxlen = sizeof(mmap_rnd_bits),
1588 .proc_handler = proc_dointvec_minmax,
1589 .extra1 = (void *)&mmap_rnd_bits_min,
1590 .extra2 = (void *)&mmap_rnd_bits_max,
1593 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
1595 .procname = "mmap_rnd_compat_bits",
1596 .data = &mmap_rnd_compat_bits,
1597 .maxlen = sizeof(mmap_rnd_compat_bits),
1599 .proc_handler = proc_dointvec_minmax,
1600 .extra1 = (void *)&mmap_rnd_compat_bits_min,
1601 .extra2 = (void *)&mmap_rnd_compat_bits_max,
1607 static struct ctl_table fs_table[] = {
1609 .procname = "inode-nr",
1610 .data = &inodes_stat,
1611 .maxlen = 2*sizeof(long),
1613 .proc_handler = proc_nr_inodes,
1616 .procname = "inode-state",
1617 .data = &inodes_stat,
1618 .maxlen = 7*sizeof(long),
1620 .proc_handler = proc_nr_inodes,
1623 .procname = "file-nr",
1624 .data = &files_stat,
1625 .maxlen = sizeof(files_stat),
1627 .proc_handler = proc_nr_files,
1630 .procname = "file-max",
1631 .data = &files_stat.max_files,
1632 .maxlen = sizeof(files_stat.max_files),
1634 .proc_handler = proc_doulongvec_minmax,
1637 .procname = "nr_open",
1638 .data = &sysctl_nr_open,
1639 .maxlen = sizeof(int),
1641 .proc_handler = proc_dointvec_minmax,
1642 .extra1 = &sysctl_nr_open_min,
1643 .extra2 = &sysctl_nr_open_max,
1646 .procname = "dentry-state",
1647 .data = &dentry_stat,
1648 .maxlen = 6*sizeof(long),
1650 .proc_handler = proc_nr_dentry,
1653 .procname = "overflowuid",
1654 .data = &fs_overflowuid,
1655 .maxlen = sizeof(int),
1657 .proc_handler = proc_dointvec_minmax,
1658 .extra1 = &minolduid,
1659 .extra2 = &maxolduid,
1662 .procname = "overflowgid",
1663 .data = &fs_overflowgid,
1664 .maxlen = sizeof(int),
1666 .proc_handler = proc_dointvec_minmax,
1667 .extra1 = &minolduid,
1668 .extra2 = &maxolduid,
1670 #ifdef CONFIG_FILE_LOCKING
1672 .procname = "leases-enable",
1673 .data = &leases_enable,
1674 .maxlen = sizeof(int),
1676 .proc_handler = proc_dointvec,
1679 #ifdef CONFIG_DNOTIFY
1681 .procname = "dir-notify-enable",
1682 .data = &dir_notify_enable,
1683 .maxlen = sizeof(int),
1685 .proc_handler = proc_dointvec,
1689 #ifdef CONFIG_FILE_LOCKING
1691 .procname = "lease-break-time",
1692 .data = &lease_break_time,
1693 .maxlen = sizeof(int),
1695 .proc_handler = proc_dointvec,
1700 .procname = "aio-nr",
1702 .maxlen = sizeof(aio_nr),
1704 .proc_handler = proc_doulongvec_minmax,
1707 .procname = "aio-max-nr",
1708 .data = &aio_max_nr,
1709 .maxlen = sizeof(aio_max_nr),
1711 .proc_handler = proc_doulongvec_minmax,
1713 #endif /* CONFIG_AIO */
1714 #ifdef CONFIG_INOTIFY_USER
1716 .procname = "inotify",
1718 .child = inotify_table,
1723 .procname = "epoll",
1725 .child = epoll_table,
1730 .procname = "protected_symlinks",
1731 .data = &sysctl_protected_symlinks,
1732 .maxlen = sizeof(int),
1734 .proc_handler = proc_dointvec_minmax,
1739 .procname = "protected_hardlinks",
1740 .data = &sysctl_protected_hardlinks,
1741 .maxlen = sizeof(int),
1743 .proc_handler = proc_dointvec_minmax,
1748 .procname = "suid_dumpable",
1749 .data = &suid_dumpable,
1750 .maxlen = sizeof(int),
1752 .proc_handler = proc_dointvec_minmax_coredump,
1756 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1758 .procname = "binfmt_misc",
1760 .child = sysctl_mount_point,
1764 .procname = "pipe-max-size",
1765 .data = &pipe_max_size,
1766 .maxlen = sizeof(int),
1768 .proc_handler = &pipe_proc_fn,
1769 .extra1 = &pipe_min_size,
1772 .procname = "pipe-user-pages-hard",
1773 .data = &pipe_user_pages_hard,
1774 .maxlen = sizeof(pipe_user_pages_hard),
1776 .proc_handler = proc_doulongvec_minmax,
1779 .procname = "pipe-user-pages-soft",
1780 .data = &pipe_user_pages_soft,
1781 .maxlen = sizeof(pipe_user_pages_soft),
1783 .proc_handler = proc_doulongvec_minmax,
1788 static struct ctl_table debug_table[] = {
1789 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1791 .procname = "exception-trace",
1792 .data = &show_unhandled_signals,
1793 .maxlen = sizeof(int),
1795 .proc_handler = proc_dointvec
1798 #if defined(CONFIG_OPTPROBES)
1800 .procname = "kprobes-optimization",
1801 .data = &sysctl_kprobes_optimization,
1802 .maxlen = sizeof(int),
1804 .proc_handler = proc_kprobes_optimization_handler,
1812 static struct ctl_table dev_table[] = {
1816 int __init sysctl_init(void)
1818 struct ctl_table_header *hdr;
1820 hdr = register_sysctl_table(sysctl_base_table);
1821 kmemleak_not_leak(hdr);
1825 #endif /* CONFIG_SYSCTL */
1831 #ifdef CONFIG_PROC_SYSCTL
1833 static int _proc_do_string(char *data, int maxlen, int write,
1834 char __user *buffer,
1835 size_t *lenp, loff_t *ppos)
1841 if (!data || !maxlen || !*lenp) {
1847 if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
1848 /* Only continue writes not past the end of buffer. */
1850 if (len > maxlen - 1)
1857 /* Start writing from beginning of buffer. */
1863 while ((p - buffer) < *lenp && len < maxlen - 1) {
1864 if (get_user(c, p++))
1866 if (c == 0 || c == '\n')
1887 if (copy_to_user(buffer, data, len))
1890 if (put_user('\n', buffer + len))
1900 static void warn_sysctl_write(struct ctl_table *table)
1902 pr_warn_once("%s wrote to %s when file position was not 0!\n"
1903 "This will not be supported in the future. To silence this\n"
1904 "warning, set kernel.sysctl_writes_strict = -1\n",
1905 current->comm, table->procname);
1909 * proc_dostring - read a string sysctl
1910 * @table: the sysctl table
1911 * @write: %TRUE if this is a write to the sysctl file
1912 * @buffer: the user buffer
1913 * @lenp: the size of the user buffer
1914 * @ppos: file position
1916 * Reads/writes a string from/to the user buffer. If the kernel
1917 * buffer provided is not large enough to hold the string, the
1918 * string is truncated. The copied string is %NULL-terminated.
1919 * If the string is being read by the user process, it is copied
1920 * and a newline '\n' is added. It is truncated if the buffer is
1923 * Returns 0 on success.
1925 int proc_dostring(struct ctl_table *table, int write,
1926 void __user *buffer, size_t *lenp, loff_t *ppos)
1928 if (write && *ppos && sysctl_writes_strict == SYSCTL_WRITES_WARN)
1929 warn_sysctl_write(table);
1931 return _proc_do_string((char *)(table->data), table->maxlen, write,
1932 (char __user *)buffer, lenp, ppos);
1935 static size_t proc_skip_spaces(char **buf)
1938 char *tmp = skip_spaces(*buf);
1944 static void proc_skip_char(char **buf, size_t *size, const char v)
1954 #define TMPBUFLEN 22
1956 * proc_get_long - reads an ASCII formatted integer from a user buffer
1958 * @buf: a kernel buffer
1959 * @size: size of the kernel buffer
1960 * @val: this is where the number will be stored
1961 * @neg: set to %TRUE if number is negative
1962 * @perm_tr: a vector which contains the allowed trailers
1963 * @perm_tr_len: size of the perm_tr vector
1964 * @tr: pointer to store the trailer character
1966 * In case of success %0 is returned and @buf and @size are updated with
1967 * the amount of bytes read. If @tr is non-NULL and a trailing
1968 * character exists (size is non-zero after returning from this
1969 * function), @tr is updated with the trailing character.
1971 static int proc_get_long(char **buf, size_t *size,
1972 unsigned long *val, bool *neg,
1973 const char *perm_tr, unsigned perm_tr_len, char *tr)
1976 char *p, tmp[TMPBUFLEN];
1982 if (len > TMPBUFLEN - 1)
1983 len = TMPBUFLEN - 1;
1985 memcpy(tmp, *buf, len);
1989 if (*p == '-' && *size > 1) {
1997 *val = simple_strtoul(p, &p, 0);
2001 /* We don't know if the next char is whitespace thus we may accept
2002 * invalid integers (e.g. 1234...a) or two integers instead of one
2003 * (e.g. 123...1). So lets not allow such large numbers. */
2004 if (len == TMPBUFLEN - 1)
2007 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2010 if (tr && (len < *size))
2020 * proc_put_long - converts an integer to a decimal ASCII formatted string
2022 * @buf: the user buffer
2023 * @size: the size of the user buffer
2024 * @val: the integer to be converted
2025 * @neg: sign of the number, %TRUE for negative
2027 * In case of success %0 is returned and @buf and @size are updated with
2028 * the amount of bytes written.
2030 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2034 char tmp[TMPBUFLEN], *p = tmp;
2036 sprintf(p, "%s%lu", neg ? "-" : "", val);
2040 if (copy_to_user(*buf, tmp, len))
2048 static int proc_put_char(void __user **buf, size_t *size, char c)
2051 char __user **buffer = (char __user **)buf;
2052 if (put_user(c, *buffer))
2054 (*size)--, (*buffer)++;
2060 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2062 int write, void *data)
2066 if (*lvalp > (unsigned long) INT_MAX + 1)
2070 if (*lvalp > (unsigned long) INT_MAX)
2078 *lvalp = -(unsigned long)val;
2081 *lvalp = (unsigned long)val;
2087 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2089 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2090 int write, void __user *buffer,
2091 size_t *lenp, loff_t *ppos,
2092 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2093 int write, void *data),
2096 int *i, vleft, first = 1, err = 0;
2098 char *kbuf = NULL, *p;
2100 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2105 i = (int *) tbl_data;
2106 vleft = table->maxlen / sizeof(*i);
2110 conv = do_proc_dointvec_conv;
2114 switch (sysctl_writes_strict) {
2115 case SYSCTL_WRITES_STRICT:
2117 case SYSCTL_WRITES_WARN:
2118 warn_sysctl_write(table);
2125 if (left > PAGE_SIZE - 1)
2126 left = PAGE_SIZE - 1;
2127 p = kbuf = memdup_user_nul(buffer, left);
2129 return PTR_ERR(kbuf);
2132 for (; left && vleft--; i++, first=0) {
2137 left -= proc_skip_spaces(&p);
2141 err = proc_get_long(&p, &left, &lval, &neg,
2143 sizeof(proc_wspace_sep), NULL);
2146 if (conv(&neg, &lval, i, 1, data)) {
2151 if (conv(&neg, &lval, i, 0, data)) {
2156 err = proc_put_char(&buffer, &left, '\t');
2159 err = proc_put_long(&buffer, &left, lval, neg);
2165 if (!write && !first && left && !err)
2166 err = proc_put_char(&buffer, &left, '\n');
2167 if (write && !err && left)
2168 left -= proc_skip_spaces(&p);
2172 return err ? : -EINVAL;
2180 static int do_proc_dointvec(struct ctl_table *table, int write,
2181 void __user *buffer, size_t *lenp, loff_t *ppos,
2182 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2183 int write, void *data),
2186 return __do_proc_dointvec(table->data, table, write,
2187 buffer, lenp, ppos, conv, data);
2191 * proc_dointvec - read a vector of integers
2192 * @table: the sysctl table
2193 * @write: %TRUE if this is a write to the sysctl file
2194 * @buffer: the user buffer
2195 * @lenp: the size of the user buffer
2196 * @ppos: file position
2198 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2199 * values from/to the user buffer, treated as an ASCII string.
2201 * Returns 0 on success.
2203 int proc_dointvec(struct ctl_table *table, int write,
2204 void __user *buffer, size_t *lenp, loff_t *ppos)
2206 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2211 * Taint values can only be increased
2212 * This means we can safely use a temporary.
2214 static int proc_taint(struct ctl_table *table, int write,
2215 void __user *buffer, size_t *lenp, loff_t *ppos)
2218 unsigned long tmptaint = get_taint();
2221 if (write && !capable(CAP_SYS_ADMIN))
2226 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2232 * Poor man's atomic or. Not worth adding a primitive
2233 * to everyone's atomic.h for this
2236 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2237 if ((tmptaint >> i) & 1)
2238 add_taint(i, LOCKDEP_STILL_OK);
2245 #ifdef CONFIG_PRINTK
2246 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2247 void __user *buffer, size_t *lenp, loff_t *ppos)
2249 if (write && !capable(CAP_SYS_ADMIN))
2252 return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2256 struct do_proc_dointvec_minmax_conv_param {
2261 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2263 int write, void *data)
2265 struct do_proc_dointvec_minmax_conv_param *param = data;
2267 int val = *negp ? -*lvalp : *lvalp;
2268 if ((param->min && *param->min > val) ||
2269 (param->max && *param->max < val))
2276 *lvalp = -(unsigned long)val;
2279 *lvalp = (unsigned long)val;
2286 * proc_dointvec_minmax - read a vector of integers with min/max values
2287 * @table: the sysctl table
2288 * @write: %TRUE if this is a write to the sysctl file
2289 * @buffer: the user buffer
2290 * @lenp: the size of the user buffer
2291 * @ppos: file position
2293 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2294 * values from/to the user buffer, treated as an ASCII string.
2296 * This routine will ensure the values are within the range specified by
2297 * table->extra1 (min) and table->extra2 (max).
2299 * Returns 0 on success.
2301 int proc_dointvec_minmax(struct ctl_table *table, int write,
2302 void __user *buffer, size_t *lenp, loff_t *ppos)
2304 struct do_proc_dointvec_minmax_conv_param param = {
2305 .min = (int *) table->extra1,
2306 .max = (int *) table->extra2,
2308 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2309 do_proc_dointvec_minmax_conv, ¶m);
2312 static void validate_coredump_safety(void)
2314 #ifdef CONFIG_COREDUMP
2315 if (suid_dumpable == SUID_DUMP_ROOT &&
2316 core_pattern[0] != '/' && core_pattern[0] != '|') {
2317 printk(KERN_WARNING "Unsafe core_pattern used with "\
2318 "suid_dumpable=2. Pipe handler or fully qualified "\
2319 "core dump path required.\n");
2324 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2325 void __user *buffer, size_t *lenp, loff_t *ppos)
2327 int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2329 validate_coredump_safety();
2333 #ifdef CONFIG_COREDUMP
2334 static int proc_dostring_coredump(struct ctl_table *table, int write,
2335 void __user *buffer, size_t *lenp, loff_t *ppos)
2337 int error = proc_dostring(table, write, buffer, lenp, ppos);
2339 validate_coredump_safety();
2344 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2345 void __user *buffer,
2346 size_t *lenp, loff_t *ppos,
2347 unsigned long convmul,
2348 unsigned long convdiv)
2350 unsigned long *i, *min, *max;
2351 int vleft, first = 1, err = 0;
2353 char *kbuf = NULL, *p;
2355 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2360 i = (unsigned long *) data;
2361 min = (unsigned long *) table->extra1;
2362 max = (unsigned long *) table->extra2;
2363 vleft = table->maxlen / sizeof(unsigned long);
2368 switch (sysctl_writes_strict) {
2369 case SYSCTL_WRITES_STRICT:
2371 case SYSCTL_WRITES_WARN:
2372 warn_sysctl_write(table);
2379 if (left > PAGE_SIZE - 1)
2380 left = PAGE_SIZE - 1;
2381 p = kbuf = memdup_user_nul(buffer, left);
2383 return PTR_ERR(kbuf);
2386 for (; left && vleft--; i++, first = 0) {
2392 left -= proc_skip_spaces(&p);
2394 err = proc_get_long(&p, &left, &val, &neg,
2396 sizeof(proc_wspace_sep), NULL);
2401 if ((min && val < *min) || (max && val > *max))
2405 val = convdiv * (*i) / convmul;
2407 err = proc_put_char(&buffer, &left, '\t');
2411 err = proc_put_long(&buffer, &left, val, false);
2417 if (!write && !first && left && !err)
2418 err = proc_put_char(&buffer, &left, '\n');
2420 left -= proc_skip_spaces(&p);
2424 return err ? : -EINVAL;
2432 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2433 void __user *buffer,
2434 size_t *lenp, loff_t *ppos,
2435 unsigned long convmul,
2436 unsigned long convdiv)
2438 return __do_proc_doulongvec_minmax(table->data, table, write,
2439 buffer, lenp, ppos, convmul, convdiv);
2443 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2444 * @table: the sysctl table
2445 * @write: %TRUE if this is a write to the sysctl file
2446 * @buffer: the user buffer
2447 * @lenp: the size of the user buffer
2448 * @ppos: file position
2450 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2451 * values from/to the user buffer, treated as an ASCII string.
2453 * This routine will ensure the values are within the range specified by
2454 * table->extra1 (min) and table->extra2 (max).
2456 * Returns 0 on success.
2458 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2459 void __user *buffer, size_t *lenp, loff_t *ppos)
2461 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2465 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2466 * @table: the sysctl table
2467 * @write: %TRUE if this is a write to the sysctl file
2468 * @buffer: the user buffer
2469 * @lenp: the size of the user buffer
2470 * @ppos: file position
2472 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2473 * values from/to the user buffer, treated as an ASCII string. The values
2474 * are treated as milliseconds, and converted to jiffies when they are stored.
2476 * This routine will ensure the values are within the range specified by
2477 * table->extra1 (min) and table->extra2 (max).
2479 * Returns 0 on success.
2481 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2482 void __user *buffer,
2483 size_t *lenp, loff_t *ppos)
2485 return do_proc_doulongvec_minmax(table, write, buffer,
2486 lenp, ppos, HZ, 1000l);
2490 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2492 int write, void *data)
2495 if (*lvalp > LONG_MAX / HZ)
2497 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2503 lval = -(unsigned long)val;
2506 lval = (unsigned long)val;
2513 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2515 int write, void *data)
2518 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2520 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2526 lval = -(unsigned long)val;
2529 lval = (unsigned long)val;
2531 *lvalp = jiffies_to_clock_t(lval);
2536 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2538 int write, void *data)
2541 unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2551 lval = -(unsigned long)val;
2554 lval = (unsigned long)val;
2556 *lvalp = jiffies_to_msecs(lval);
2562 * proc_dointvec_jiffies - read a vector of integers as seconds
2563 * @table: the sysctl table
2564 * @write: %TRUE if this is a write to the sysctl file
2565 * @buffer: the user buffer
2566 * @lenp: the size of the user buffer
2567 * @ppos: file position
2569 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2570 * values from/to the user buffer, treated as an ASCII string.
2571 * The values read are assumed to be in seconds, and are converted into
2574 * Returns 0 on success.
2576 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2577 void __user *buffer, size_t *lenp, loff_t *ppos)
2579 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2580 do_proc_dointvec_jiffies_conv,NULL);
2584 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2585 * @table: the sysctl table
2586 * @write: %TRUE if this is a write to the sysctl file
2587 * @buffer: the user buffer
2588 * @lenp: the size of the user buffer
2589 * @ppos: pointer to the file position
2591 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2592 * values from/to the user buffer, treated as an ASCII string.
2593 * The values read are assumed to be in 1/USER_HZ seconds, and
2594 * are converted into jiffies.
2596 * Returns 0 on success.
2598 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2599 void __user *buffer, size_t *lenp, loff_t *ppos)
2601 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2602 do_proc_dointvec_userhz_jiffies_conv,NULL);
2606 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2607 * @table: the sysctl table
2608 * @write: %TRUE if this is a write to the sysctl file
2609 * @buffer: the user buffer
2610 * @lenp: the size of the user buffer
2611 * @ppos: file position
2612 * @ppos: the current position in the file
2614 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2615 * values from/to the user buffer, treated as an ASCII string.
2616 * The values read are assumed to be in 1/1000 seconds, and
2617 * are converted into jiffies.
2619 * Returns 0 on success.
2621 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2622 void __user *buffer, size_t *lenp, loff_t *ppos)
2624 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2625 do_proc_dointvec_ms_jiffies_conv, NULL);
2628 static int proc_do_cad_pid(struct ctl_table *table, int write,
2629 void __user *buffer, size_t *lenp, loff_t *ppos)
2631 struct pid *new_pid;
2635 tmp = pid_vnr(cad_pid);
2637 r = __do_proc_dointvec(&tmp, table, write, buffer,
2638 lenp, ppos, NULL, NULL);
2642 new_pid = find_get_pid(tmp);
2646 put_pid(xchg(&cad_pid, new_pid));
2651 * proc_do_large_bitmap - read/write from/to a large bitmap
2652 * @table: the sysctl table
2653 * @write: %TRUE if this is a write to the sysctl file
2654 * @buffer: the user buffer
2655 * @lenp: the size of the user buffer
2656 * @ppos: file position
2658 * The bitmap is stored at table->data and the bitmap length (in bits)
2661 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2662 * large bitmaps may be represented in a compact manner. Writing into
2663 * the file will clear the bitmap then update it with the given input.
2665 * Returns 0 on success.
2667 int proc_do_large_bitmap(struct ctl_table *table, int write,
2668 void __user *buffer, size_t *lenp, loff_t *ppos)
2672 size_t left = *lenp;
2673 unsigned long bitmap_len = table->maxlen;
2674 unsigned long *bitmap = *(unsigned long **) table->data;
2675 unsigned long *tmp_bitmap = NULL;
2676 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2678 if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
2686 if (left > PAGE_SIZE - 1)
2687 left = PAGE_SIZE - 1;
2689 p = kbuf = memdup_user_nul(buffer, left);
2691 return PTR_ERR(kbuf);
2693 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2699 proc_skip_char(&p, &left, '\n');
2700 while (!err && left) {
2701 unsigned long val_a, val_b;
2704 err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
2708 if (val_a >= bitmap_len || neg) {
2720 err = proc_get_long(&p, &left, &val_b,
2721 &neg, tr_b, sizeof(tr_b),
2725 if (val_b >= bitmap_len || neg ||
2736 bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
2738 proc_skip_char(&p, &left, '\n');
2742 unsigned long bit_a, bit_b = 0;
2745 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2746 if (bit_a >= bitmap_len)
2748 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2752 err = proc_put_char(&buffer, &left, ',');
2756 err = proc_put_long(&buffer, &left, bit_a, false);
2759 if (bit_a != bit_b) {
2760 err = proc_put_char(&buffer, &left, '-');
2763 err = proc_put_long(&buffer, &left, bit_b, false);
2771 err = proc_put_char(&buffer, &left, '\n');
2777 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2779 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
2791 #else /* CONFIG_PROC_SYSCTL */
2793 int proc_dostring(struct ctl_table *table, int write,
2794 void __user *buffer, size_t *lenp, loff_t *ppos)
2799 int proc_dointvec(struct ctl_table *table, int write,
2800 void __user *buffer, size_t *lenp, loff_t *ppos)
2805 int proc_dointvec_minmax(struct ctl_table *table, int write,
2806 void __user *buffer, size_t *lenp, loff_t *ppos)
2811 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2812 void __user *buffer, size_t *lenp, loff_t *ppos)
2817 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2818 void __user *buffer, size_t *lenp, loff_t *ppos)
2823 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2824 void __user *buffer, size_t *lenp, loff_t *ppos)
2829 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2830 void __user *buffer, size_t *lenp, loff_t *ppos)
2835 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2836 void __user *buffer,
2837 size_t *lenp, loff_t *ppos)
2843 #endif /* CONFIG_PROC_SYSCTL */
2846 * No sense putting this after each symbol definition, twice,
2847 * exception granted :-)
2849 EXPORT_SYMBOL(proc_dointvec);
2850 EXPORT_SYMBOL(proc_dointvec_jiffies);
2851 EXPORT_SYMBOL(proc_dointvec_minmax);
2852 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2853 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2854 EXPORT_SYMBOL(proc_dostring);
2855 EXPORT_SYMBOL(proc_doulongvec_minmax);
2856 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);