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 extra_free_kbytes;
108 extern int pid_max_min, pid_max_max;
109 extern int percpu_pagelist_fraction;
110 extern int compat_log;
111 extern int latencytop_enabled;
112 extern int sysctl_nr_open_min, sysctl_nr_open_max;
114 extern int sysctl_nr_trim_pages;
117 /* Constants used for minimum and maximum */
118 #ifdef CONFIG_LOCKUP_DETECTOR
119 static int sixty = 60;
122 static int __maybe_unused neg_one = -1;
125 static int __maybe_unused one = 1;
126 static int __maybe_unused two = 2;
127 static int __maybe_unused four = 4;
128 static unsigned long one_ul = 1;
129 static int one_hundred = 100;
131 static int ten_thousand = 10000;
134 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
135 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
137 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
138 static int maxolduid = 65535;
139 static int minolduid;
141 static int ngroups_max = NGROUPS_MAX;
142 static const int cap_last_cap = CAP_LAST_CAP;
144 /*this is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs */
145 #ifdef CONFIG_DETECT_HUNG_TASK
146 static unsigned long hung_task_timeout_max = (LONG_MAX/HZ);
149 #ifdef CONFIG_INOTIFY_USER
150 #include <linux/inotify.h>
156 extern int pwrsw_enabled;
159 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
160 extern int unaligned_enabled;
164 extern int unaligned_dump_stack;
167 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
168 extern int no_unaligned_warning;
171 #ifdef CONFIG_PROC_SYSCTL
173 #define SYSCTL_WRITES_LEGACY -1
174 #define SYSCTL_WRITES_WARN 0
175 #define SYSCTL_WRITES_STRICT 1
177 static int sysctl_writes_strict = SYSCTL_WRITES_WARN;
179 static int proc_do_cad_pid(struct ctl_table *table, int write,
180 void __user *buffer, size_t *lenp, loff_t *ppos);
181 static int proc_taint(struct ctl_table *table, int write,
182 void __user *buffer, size_t *lenp, loff_t *ppos);
186 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
187 void __user *buffer, size_t *lenp, loff_t *ppos);
190 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
191 void __user *buffer, size_t *lenp, loff_t *ppos);
192 #ifdef CONFIG_COREDUMP
193 static int proc_dostring_coredump(struct ctl_table *table, int write,
194 void __user *buffer, size_t *lenp, loff_t *ppos);
197 #ifdef CONFIG_MAGIC_SYSRQ
198 /* Note: sysrq code uses it's own private copy */
199 static int __sysrq_enabled = CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE;
201 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
202 void __user *buffer, size_t *lenp,
207 error = proc_dointvec(table, write, buffer, lenp, ppos);
212 sysrq_toggle_support(__sysrq_enabled);
219 static struct ctl_table kern_table[];
220 static struct ctl_table vm_table[];
221 static struct ctl_table fs_table[];
222 static struct ctl_table debug_table[];
223 static struct ctl_table dev_table[];
224 extern struct ctl_table random_table[];
226 extern struct ctl_table epoll_table[];
229 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
230 int sysctl_legacy_va_layout;
233 /* The default sysctl tables: */
235 static struct ctl_table sysctl_base_table[] = {
237 .procname = "kernel",
254 .child = debug_table,
264 #ifdef CONFIG_SCHED_DEBUG
265 static int min_sched_granularity_ns = 100000; /* 100 usecs */
266 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
267 static int min_wakeup_granularity_ns; /* 0 usecs */
268 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
270 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
271 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
272 #endif /* CONFIG_SMP */
273 #endif /* CONFIG_SCHED_DEBUG */
275 #ifdef CONFIG_COMPACTION
276 static int min_extfrag_threshold;
277 static int max_extfrag_threshold = 1000;
280 static struct ctl_table kern_table[] = {
282 .procname = "sched_child_runs_first",
283 .data = &sysctl_sched_child_runs_first,
284 .maxlen = sizeof(unsigned int),
286 .proc_handler = proc_dointvec,
288 #ifdef CONFIG_SCHED_DEBUG
290 .procname = "sched_min_granularity_ns",
291 .data = &sysctl_sched_min_granularity,
292 .maxlen = sizeof(unsigned int),
294 .proc_handler = sched_proc_update_handler,
295 .extra1 = &min_sched_granularity_ns,
296 .extra2 = &max_sched_granularity_ns,
299 .procname = "sched_latency_ns",
300 .data = &sysctl_sched_latency,
301 .maxlen = sizeof(unsigned int),
303 .proc_handler = sched_proc_update_handler,
304 .extra1 = &min_sched_granularity_ns,
305 .extra2 = &max_sched_granularity_ns,
308 .procname = "sched_wakeup_granularity_ns",
309 .data = &sysctl_sched_wakeup_granularity,
310 .maxlen = sizeof(unsigned int),
312 .proc_handler = sched_proc_update_handler,
313 .extra1 = &min_wakeup_granularity_ns,
314 .extra2 = &max_wakeup_granularity_ns,
318 .procname = "sched_tunable_scaling",
319 .data = &sysctl_sched_tunable_scaling,
320 .maxlen = sizeof(enum sched_tunable_scaling),
322 .proc_handler = sched_proc_update_handler,
323 .extra1 = &min_sched_tunable_scaling,
324 .extra2 = &max_sched_tunable_scaling,
327 .procname = "sched_migration_cost_ns",
328 .data = &sysctl_sched_migration_cost,
329 .maxlen = sizeof(unsigned int),
331 .proc_handler = proc_dointvec,
334 .procname = "sched_nr_migrate",
335 .data = &sysctl_sched_nr_migrate,
336 .maxlen = sizeof(unsigned int),
338 .proc_handler = proc_dointvec,
341 .procname = "sched_time_avg_ms",
342 .data = &sysctl_sched_time_avg,
343 .maxlen = sizeof(unsigned int),
345 .proc_handler = proc_dointvec,
348 .procname = "sched_shares_window_ns",
349 .data = &sysctl_sched_shares_window,
350 .maxlen = sizeof(unsigned int),
352 .proc_handler = proc_dointvec,
354 #endif /* CONFIG_SMP */
355 #ifdef CONFIG_NUMA_BALANCING
357 .procname = "numa_balancing_scan_delay_ms",
358 .data = &sysctl_numa_balancing_scan_delay,
359 .maxlen = sizeof(unsigned int),
361 .proc_handler = proc_dointvec,
364 .procname = "numa_balancing_scan_period_min_ms",
365 .data = &sysctl_numa_balancing_scan_period_min,
366 .maxlen = sizeof(unsigned int),
368 .proc_handler = proc_dointvec,
371 .procname = "numa_balancing_scan_period_max_ms",
372 .data = &sysctl_numa_balancing_scan_period_max,
373 .maxlen = sizeof(unsigned int),
375 .proc_handler = proc_dointvec,
378 .procname = "numa_balancing_scan_size_mb",
379 .data = &sysctl_numa_balancing_scan_size,
380 .maxlen = sizeof(unsigned int),
382 .proc_handler = proc_dointvec_minmax,
386 .procname = "numa_balancing",
387 .data = NULL, /* filled in by handler */
388 .maxlen = sizeof(unsigned int),
390 .proc_handler = sysctl_numa_balancing,
394 #endif /* CONFIG_NUMA_BALANCING */
395 #endif /* CONFIG_SCHED_DEBUG */
397 .procname = "sched_rt_period_us",
398 .data = &sysctl_sched_rt_period,
399 .maxlen = sizeof(unsigned int),
401 .proc_handler = sched_rt_handler,
404 .procname = "sched_rt_runtime_us",
405 .data = &sysctl_sched_rt_runtime,
406 .maxlen = sizeof(int),
408 .proc_handler = sched_rt_handler,
411 .procname = "sched_rr_timeslice_ms",
412 .data = &sched_rr_timeslice,
413 .maxlen = sizeof(int),
415 .proc_handler = sched_rr_handler,
417 #ifdef CONFIG_SCHED_AUTOGROUP
419 .procname = "sched_autogroup_enabled",
420 .data = &sysctl_sched_autogroup_enabled,
421 .maxlen = sizeof(unsigned int),
423 .proc_handler = proc_dointvec_minmax,
428 #ifdef CONFIG_CFS_BANDWIDTH
430 .procname = "sched_cfs_bandwidth_slice_us",
431 .data = &sysctl_sched_cfs_bandwidth_slice,
432 .maxlen = sizeof(unsigned int),
434 .proc_handler = proc_dointvec_minmax,
438 #ifdef CONFIG_PROVE_LOCKING
440 .procname = "prove_locking",
441 .data = &prove_locking,
442 .maxlen = sizeof(int),
444 .proc_handler = proc_dointvec,
447 #ifdef CONFIG_LOCK_STAT
449 .procname = "lock_stat",
451 .maxlen = sizeof(int),
453 .proc_handler = proc_dointvec,
458 .data = &panic_timeout,
459 .maxlen = sizeof(int),
461 .proc_handler = proc_dointvec,
463 #ifdef CONFIG_COREDUMP
465 .procname = "core_uses_pid",
466 .data = &core_uses_pid,
467 .maxlen = sizeof(int),
469 .proc_handler = proc_dointvec,
472 .procname = "core_pattern",
473 .data = core_pattern,
474 .maxlen = CORENAME_MAX_SIZE,
476 .proc_handler = proc_dostring_coredump,
479 .procname = "core_pipe_limit",
480 .data = &core_pipe_limit,
481 .maxlen = sizeof(unsigned int),
483 .proc_handler = proc_dointvec,
486 #ifdef CONFIG_PROC_SYSCTL
488 .procname = "tainted",
489 .maxlen = sizeof(long),
491 .proc_handler = proc_taint,
494 .procname = "sysctl_writes_strict",
495 .data = &sysctl_writes_strict,
496 .maxlen = sizeof(int),
498 .proc_handler = proc_dointvec_minmax,
503 #ifdef CONFIG_LATENCYTOP
505 .procname = "latencytop",
506 .data = &latencytop_enabled,
507 .maxlen = sizeof(int),
509 .proc_handler = proc_dointvec,
512 #ifdef CONFIG_BLK_DEV_INITRD
514 .procname = "real-root-dev",
515 .data = &real_root_dev,
516 .maxlen = sizeof(int),
518 .proc_handler = proc_dointvec,
522 .procname = "print-fatal-signals",
523 .data = &print_fatal_signals,
524 .maxlen = sizeof(int),
526 .proc_handler = proc_dointvec,
530 .procname = "reboot-cmd",
531 .data = reboot_command,
534 .proc_handler = proc_dostring,
537 .procname = "stop-a",
538 .data = &stop_a_enabled,
539 .maxlen = sizeof (int),
541 .proc_handler = proc_dointvec,
544 .procname = "scons-poweroff",
545 .data = &scons_pwroff,
546 .maxlen = sizeof (int),
548 .proc_handler = proc_dointvec,
551 #ifdef CONFIG_SPARC64
553 .procname = "tsb-ratio",
554 .data = &sysctl_tsb_ratio,
555 .maxlen = sizeof (int),
557 .proc_handler = proc_dointvec,
562 .procname = "soft-power",
563 .data = &pwrsw_enabled,
564 .maxlen = sizeof (int),
566 .proc_handler = proc_dointvec,
569 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
571 .procname = "unaligned-trap",
572 .data = &unaligned_enabled,
573 .maxlen = sizeof (int),
575 .proc_handler = proc_dointvec,
579 .procname = "ctrl-alt-del",
581 .maxlen = sizeof(int),
583 .proc_handler = proc_dointvec,
585 #ifdef CONFIG_FUNCTION_TRACER
587 .procname = "ftrace_enabled",
588 .data = &ftrace_enabled,
589 .maxlen = sizeof(int),
591 .proc_handler = ftrace_enable_sysctl,
594 #ifdef CONFIG_STACK_TRACER
596 .procname = "stack_tracer_enabled",
597 .data = &stack_tracer_enabled,
598 .maxlen = sizeof(int),
600 .proc_handler = stack_trace_sysctl,
603 #ifdef CONFIG_TRACING
605 .procname = "ftrace_dump_on_oops",
606 .data = &ftrace_dump_on_oops,
607 .maxlen = sizeof(int),
609 .proc_handler = proc_dointvec,
612 .procname = "traceoff_on_warning",
613 .data = &__disable_trace_on_warning,
614 .maxlen = sizeof(__disable_trace_on_warning),
616 .proc_handler = proc_dointvec,
619 .procname = "tracepoint_printk",
620 .data = &tracepoint_printk,
621 .maxlen = sizeof(tracepoint_printk),
623 .proc_handler = proc_dointvec,
626 #ifdef CONFIG_KEXEC_CORE
628 .procname = "kexec_load_disabled",
629 .data = &kexec_load_disabled,
630 .maxlen = sizeof(int),
632 /* only handle a transition from default "0" to "1" */
633 .proc_handler = proc_dointvec_minmax,
638 #ifdef CONFIG_MODULES
640 .procname = "modprobe",
641 .data = &modprobe_path,
642 .maxlen = KMOD_PATH_LEN,
644 .proc_handler = proc_dostring,
647 .procname = "modules_disabled",
648 .data = &modules_disabled,
649 .maxlen = sizeof(int),
651 /* only handle a transition from default "0" to "1" */
652 .proc_handler = proc_dointvec_minmax,
657 #ifdef CONFIG_UEVENT_HELPER
659 .procname = "hotplug",
660 .data = &uevent_helper,
661 .maxlen = UEVENT_HELPER_PATH_LEN,
663 .proc_handler = proc_dostring,
666 #ifdef CONFIG_CHR_DEV_SG
668 .procname = "sg-big-buff",
669 .data = &sg_big_buff,
670 .maxlen = sizeof (int),
672 .proc_handler = proc_dointvec,
675 #ifdef CONFIG_BSD_PROCESS_ACCT
679 .maxlen = 3*sizeof(int),
681 .proc_handler = proc_dointvec,
684 #ifdef CONFIG_MAGIC_SYSRQ
687 .data = &__sysrq_enabled,
688 .maxlen = sizeof (int),
690 .proc_handler = sysrq_sysctl_handler,
693 #ifdef CONFIG_PROC_SYSCTL
695 .procname = "cad_pid",
697 .maxlen = sizeof (int),
699 .proc_handler = proc_do_cad_pid,
703 .procname = "threads-max",
705 .maxlen = sizeof(int),
707 .proc_handler = sysctl_max_threads,
710 .procname = "random",
712 .child = random_table,
715 .procname = "usermodehelper",
717 .child = usermodehelper_table,
720 .procname = "overflowuid",
721 .data = &overflowuid,
722 .maxlen = sizeof(int),
724 .proc_handler = proc_dointvec_minmax,
725 .extra1 = &minolduid,
726 .extra2 = &maxolduid,
729 .procname = "overflowgid",
730 .data = &overflowgid,
731 .maxlen = sizeof(int),
733 .proc_handler = proc_dointvec_minmax,
734 .extra1 = &minolduid,
735 .extra2 = &maxolduid,
738 #ifdef CONFIG_MATHEMU
740 .procname = "ieee_emulation_warnings",
741 .data = &sysctl_ieee_emulation_warnings,
742 .maxlen = sizeof(int),
744 .proc_handler = proc_dointvec,
748 .procname = "userprocess_debug",
749 .data = &show_unhandled_signals,
750 .maxlen = sizeof(int),
752 .proc_handler = proc_dointvec,
756 .procname = "pid_max",
758 .maxlen = sizeof (int),
760 .proc_handler = proc_dointvec_minmax,
761 .extra1 = &pid_max_min,
762 .extra2 = &pid_max_max,
765 .procname = "panic_on_oops",
766 .data = &panic_on_oops,
767 .maxlen = sizeof(int),
769 .proc_handler = proc_dointvec,
771 #if defined CONFIG_PRINTK
773 .procname = "printk",
774 .data = &console_loglevel,
775 .maxlen = 4*sizeof(int),
777 .proc_handler = proc_dointvec,
780 .procname = "printk_ratelimit",
781 .data = &printk_ratelimit_state.interval,
782 .maxlen = sizeof(int),
784 .proc_handler = proc_dointvec_jiffies,
787 .procname = "printk_ratelimit_burst",
788 .data = &printk_ratelimit_state.burst,
789 .maxlen = sizeof(int),
791 .proc_handler = proc_dointvec,
794 .procname = "printk_delay",
795 .data = &printk_delay_msec,
796 .maxlen = sizeof(int),
798 .proc_handler = proc_dointvec_minmax,
800 .extra2 = &ten_thousand,
803 .procname = "dmesg_restrict",
804 .data = &dmesg_restrict,
805 .maxlen = sizeof(int),
807 .proc_handler = proc_dointvec_minmax_sysadmin,
812 .procname = "kptr_restrict",
813 .data = &kptr_restrict,
814 .maxlen = sizeof(int),
816 .proc_handler = proc_dointvec_minmax_sysadmin,
822 .procname = "ngroups_max",
823 .data = &ngroups_max,
824 .maxlen = sizeof (int),
826 .proc_handler = proc_dointvec,
829 .procname = "cap_last_cap",
830 .data = (void *)&cap_last_cap,
831 .maxlen = sizeof(int),
833 .proc_handler = proc_dointvec,
835 #if defined(CONFIG_LOCKUP_DETECTOR)
837 .procname = "watchdog",
838 .data = &watchdog_user_enabled,
839 .maxlen = sizeof (int),
841 .proc_handler = proc_watchdog,
846 .procname = "watchdog_thresh",
847 .data = &watchdog_thresh,
848 .maxlen = sizeof(int),
850 .proc_handler = proc_watchdog_thresh,
855 .procname = "nmi_watchdog",
856 .data = &nmi_watchdog_enabled,
857 .maxlen = sizeof (int),
859 .proc_handler = proc_nmi_watchdog,
861 #if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)
868 .procname = "soft_watchdog",
869 .data = &soft_watchdog_enabled,
870 .maxlen = sizeof (int),
872 .proc_handler = proc_soft_watchdog,
877 .procname = "watchdog_cpumask",
878 .data = &watchdog_cpumask_bits,
881 .proc_handler = proc_watchdog_cpumask,
884 .procname = "softlockup_panic",
885 .data = &softlockup_panic,
886 .maxlen = sizeof(int),
888 .proc_handler = proc_dointvec_minmax,
892 #ifdef CONFIG_HARDLOCKUP_DETECTOR
894 .procname = "hardlockup_panic",
895 .data = &hardlockup_panic,
896 .maxlen = sizeof(int),
898 .proc_handler = proc_dointvec_minmax,
905 .procname = "softlockup_all_cpu_backtrace",
906 .data = &sysctl_softlockup_all_cpu_backtrace,
907 .maxlen = sizeof(int),
909 .proc_handler = proc_dointvec_minmax,
914 .procname = "hardlockup_all_cpu_backtrace",
915 .data = &sysctl_hardlockup_all_cpu_backtrace,
916 .maxlen = sizeof(int),
918 .proc_handler = proc_dointvec_minmax,
922 #endif /* CONFIG_SMP */
924 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
926 .procname = "unknown_nmi_panic",
927 .data = &unknown_nmi_panic,
928 .maxlen = sizeof (int),
930 .proc_handler = proc_dointvec,
933 #if defined(CONFIG_X86)
935 .procname = "panic_on_unrecovered_nmi",
936 .data = &panic_on_unrecovered_nmi,
937 .maxlen = sizeof(int),
939 .proc_handler = proc_dointvec,
942 .procname = "panic_on_io_nmi",
943 .data = &panic_on_io_nmi,
944 .maxlen = sizeof(int),
946 .proc_handler = proc_dointvec,
948 #ifdef CONFIG_DEBUG_STACKOVERFLOW
950 .procname = "panic_on_stackoverflow",
951 .data = &sysctl_panic_on_stackoverflow,
952 .maxlen = sizeof(int),
954 .proc_handler = proc_dointvec,
958 .procname = "bootloader_type",
959 .data = &bootloader_type,
960 .maxlen = sizeof (int),
962 .proc_handler = proc_dointvec,
965 .procname = "bootloader_version",
966 .data = &bootloader_version,
967 .maxlen = sizeof (int),
969 .proc_handler = proc_dointvec,
972 .procname = "kstack_depth_to_print",
973 .data = &kstack_depth_to_print,
974 .maxlen = sizeof(int),
976 .proc_handler = proc_dointvec,
979 .procname = "io_delay_type",
980 .data = &io_delay_type,
981 .maxlen = sizeof(int),
983 .proc_handler = proc_dointvec,
986 #if defined(CONFIG_MMU)
988 .procname = "randomize_va_space",
989 .data = &randomize_va_space,
990 .maxlen = sizeof(int),
992 .proc_handler = proc_dointvec,
995 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
997 .procname = "spin_retry",
999 .maxlen = sizeof (int),
1001 .proc_handler = proc_dointvec,
1004 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1006 .procname = "acpi_video_flags",
1007 .data = &acpi_realmode_flags,
1008 .maxlen = sizeof (unsigned long),
1010 .proc_handler = proc_doulongvec_minmax,
1013 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1015 .procname = "ignore-unaligned-usertrap",
1016 .data = &no_unaligned_warning,
1017 .maxlen = sizeof (int),
1019 .proc_handler = proc_dointvec,
1024 .procname = "unaligned-dump-stack",
1025 .data = &unaligned_dump_stack,
1026 .maxlen = sizeof (int),
1028 .proc_handler = proc_dointvec,
1031 #ifdef CONFIG_DETECT_HUNG_TASK
1033 .procname = "hung_task_panic",
1034 .data = &sysctl_hung_task_panic,
1035 .maxlen = sizeof(int),
1037 .proc_handler = proc_dointvec_minmax,
1042 .procname = "hung_task_check_count",
1043 .data = &sysctl_hung_task_check_count,
1044 .maxlen = sizeof(int),
1046 .proc_handler = proc_dointvec_minmax,
1050 .procname = "hung_task_timeout_secs",
1051 .data = &sysctl_hung_task_timeout_secs,
1052 .maxlen = sizeof(unsigned long),
1054 .proc_handler = proc_dohung_task_timeout_secs,
1055 .extra2 = &hung_task_timeout_max,
1058 .procname = "hung_task_warnings",
1059 .data = &sysctl_hung_task_warnings,
1060 .maxlen = sizeof(int),
1062 .proc_handler = proc_dointvec_minmax,
1066 #ifdef CONFIG_COMPAT
1068 .procname = "compat-log",
1069 .data = &compat_log,
1070 .maxlen = sizeof (int),
1072 .proc_handler = proc_dointvec,
1075 #ifdef CONFIG_RT_MUTEXES
1077 .procname = "max_lock_depth",
1078 .data = &max_lock_depth,
1079 .maxlen = sizeof(int),
1081 .proc_handler = proc_dointvec,
1085 .procname = "poweroff_cmd",
1086 .data = &poweroff_cmd,
1087 .maxlen = POWEROFF_CMD_PATH_LEN,
1089 .proc_handler = proc_dostring,
1095 .child = key_sysctls,
1098 #ifdef CONFIG_PERF_EVENTS
1100 * User-space scripts rely on the existence of this file
1101 * as a feature check for perf_events being enabled.
1103 * So it's an ABI, do not remove!
1106 .procname = "perf_event_paranoid",
1107 .data = &sysctl_perf_event_paranoid,
1108 .maxlen = sizeof(sysctl_perf_event_paranoid),
1110 .proc_handler = proc_dointvec,
1113 .procname = "perf_event_mlock_kb",
1114 .data = &sysctl_perf_event_mlock,
1115 .maxlen = sizeof(sysctl_perf_event_mlock),
1117 .proc_handler = proc_dointvec,
1120 .procname = "perf_event_max_sample_rate",
1121 .data = &sysctl_perf_event_sample_rate,
1122 .maxlen = sizeof(sysctl_perf_event_sample_rate),
1124 .proc_handler = perf_proc_update_handler,
1128 .procname = "perf_cpu_time_max_percent",
1129 .data = &sysctl_perf_cpu_time_max_percent,
1130 .maxlen = sizeof(sysctl_perf_cpu_time_max_percent),
1132 .proc_handler = perf_cpu_time_max_percent_handler,
1134 .extra2 = &one_hundred,
1137 #ifdef CONFIG_KMEMCHECK
1139 .procname = "kmemcheck",
1140 .data = &kmemcheck_enabled,
1141 .maxlen = sizeof(int),
1143 .proc_handler = proc_dointvec,
1147 .procname = "panic_on_warn",
1148 .data = &panic_on_warn,
1149 .maxlen = sizeof(int),
1151 .proc_handler = proc_dointvec_minmax,
1155 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1157 .procname = "timer_migration",
1158 .data = &sysctl_timer_migration,
1159 .maxlen = sizeof(unsigned int),
1161 .proc_handler = timer_migration_handler,
1164 #ifdef CONFIG_BPF_SYSCALL
1166 .procname = "unprivileged_bpf_disabled",
1167 .data = &sysctl_unprivileged_bpf_disabled,
1168 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled),
1170 /* only handle a transition from default "0" to "1" */
1171 .proc_handler = proc_dointvec_minmax,
1179 static struct ctl_table vm_table[] = {
1181 .procname = "overcommit_memory",
1182 .data = &sysctl_overcommit_memory,
1183 .maxlen = sizeof(sysctl_overcommit_memory),
1185 .proc_handler = proc_dointvec_minmax,
1190 .procname = "panic_on_oom",
1191 .data = &sysctl_panic_on_oom,
1192 .maxlen = sizeof(sysctl_panic_on_oom),
1194 .proc_handler = proc_dointvec_minmax,
1199 .procname = "oom_kill_allocating_task",
1200 .data = &sysctl_oom_kill_allocating_task,
1201 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1203 .proc_handler = proc_dointvec,
1206 .procname = "oom_dump_tasks",
1207 .data = &sysctl_oom_dump_tasks,
1208 .maxlen = sizeof(sysctl_oom_dump_tasks),
1210 .proc_handler = proc_dointvec,
1213 .procname = "overcommit_ratio",
1214 .data = &sysctl_overcommit_ratio,
1215 .maxlen = sizeof(sysctl_overcommit_ratio),
1217 .proc_handler = overcommit_ratio_handler,
1220 .procname = "overcommit_kbytes",
1221 .data = &sysctl_overcommit_kbytes,
1222 .maxlen = sizeof(sysctl_overcommit_kbytes),
1224 .proc_handler = overcommit_kbytes_handler,
1227 .procname = "page-cluster",
1228 .data = &page_cluster,
1229 .maxlen = sizeof(int),
1231 .proc_handler = proc_dointvec_minmax,
1235 .procname = "dirty_background_ratio",
1236 .data = &dirty_background_ratio,
1237 .maxlen = sizeof(dirty_background_ratio),
1239 .proc_handler = dirty_background_ratio_handler,
1241 .extra2 = &one_hundred,
1244 .procname = "dirty_background_bytes",
1245 .data = &dirty_background_bytes,
1246 .maxlen = sizeof(dirty_background_bytes),
1248 .proc_handler = dirty_background_bytes_handler,
1252 .procname = "dirty_ratio",
1253 .data = &vm_dirty_ratio,
1254 .maxlen = sizeof(vm_dirty_ratio),
1256 .proc_handler = dirty_ratio_handler,
1258 .extra2 = &one_hundred,
1261 .procname = "dirty_bytes",
1262 .data = &vm_dirty_bytes,
1263 .maxlen = sizeof(vm_dirty_bytes),
1265 .proc_handler = dirty_bytes_handler,
1266 .extra1 = &dirty_bytes_min,
1269 .procname = "dirty_writeback_centisecs",
1270 .data = &dirty_writeback_interval,
1271 .maxlen = sizeof(dirty_writeback_interval),
1273 .proc_handler = dirty_writeback_centisecs_handler,
1276 .procname = "dirty_expire_centisecs",
1277 .data = &dirty_expire_interval,
1278 .maxlen = sizeof(dirty_expire_interval),
1280 .proc_handler = proc_dointvec_minmax,
1284 .procname = "dirtytime_expire_seconds",
1285 .data = &dirtytime_expire_interval,
1286 .maxlen = sizeof(dirty_expire_interval),
1288 .proc_handler = dirtytime_interval_handler,
1292 .procname = "nr_pdflush_threads",
1293 .mode = 0444 /* read-only */,
1294 .proc_handler = pdflush_proc_obsolete,
1297 .procname = "swappiness",
1298 .data = &vm_swappiness,
1299 .maxlen = sizeof(vm_swappiness),
1301 .proc_handler = proc_dointvec_minmax,
1303 .extra2 = &one_hundred,
1305 #ifdef CONFIG_HUGETLB_PAGE
1307 .procname = "nr_hugepages",
1309 .maxlen = sizeof(unsigned long),
1311 .proc_handler = hugetlb_sysctl_handler,
1315 .procname = "nr_hugepages_mempolicy",
1317 .maxlen = sizeof(unsigned long),
1319 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1323 .procname = "hugetlb_shm_group",
1324 .data = &sysctl_hugetlb_shm_group,
1325 .maxlen = sizeof(gid_t),
1327 .proc_handler = proc_dointvec,
1330 .procname = "hugepages_treat_as_movable",
1331 .data = &hugepages_treat_as_movable,
1332 .maxlen = sizeof(int),
1334 .proc_handler = proc_dointvec,
1337 .procname = "nr_overcommit_hugepages",
1339 .maxlen = sizeof(unsigned long),
1341 .proc_handler = hugetlb_overcommit_handler,
1345 .procname = "lowmem_reserve_ratio",
1346 .data = &sysctl_lowmem_reserve_ratio,
1347 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1349 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1352 .procname = "drop_caches",
1353 .data = &sysctl_drop_caches,
1354 .maxlen = sizeof(int),
1356 .proc_handler = drop_caches_sysctl_handler,
1360 #ifdef CONFIG_COMPACTION
1362 .procname = "compact_memory",
1363 .data = &sysctl_compact_memory,
1364 .maxlen = sizeof(int),
1366 .proc_handler = sysctl_compaction_handler,
1369 .procname = "extfrag_threshold",
1370 .data = &sysctl_extfrag_threshold,
1371 .maxlen = sizeof(int),
1373 .proc_handler = sysctl_extfrag_handler,
1374 .extra1 = &min_extfrag_threshold,
1375 .extra2 = &max_extfrag_threshold,
1378 .procname = "compact_unevictable_allowed",
1379 .data = &sysctl_compact_unevictable_allowed,
1380 .maxlen = sizeof(int),
1382 .proc_handler = proc_dointvec,
1387 #endif /* CONFIG_COMPACTION */
1389 .procname = "min_free_kbytes",
1390 .data = &min_free_kbytes,
1391 .maxlen = sizeof(min_free_kbytes),
1393 .proc_handler = min_free_kbytes_sysctl_handler,
1397 .procname = "extra_free_kbytes",
1398 .data = &extra_free_kbytes,
1399 .maxlen = sizeof(extra_free_kbytes),
1401 .proc_handler = min_free_kbytes_sysctl_handler,
1405 .procname = "percpu_pagelist_fraction",
1406 .data = &percpu_pagelist_fraction,
1407 .maxlen = sizeof(percpu_pagelist_fraction),
1409 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1414 .procname = "max_map_count",
1415 .data = &sysctl_max_map_count,
1416 .maxlen = sizeof(sysctl_max_map_count),
1418 .proc_handler = proc_dointvec_minmax,
1423 .procname = "nr_trim_pages",
1424 .data = &sysctl_nr_trim_pages,
1425 .maxlen = sizeof(sysctl_nr_trim_pages),
1427 .proc_handler = proc_dointvec_minmax,
1432 .procname = "laptop_mode",
1433 .data = &laptop_mode,
1434 .maxlen = sizeof(laptop_mode),
1436 .proc_handler = proc_dointvec_jiffies,
1439 .procname = "block_dump",
1440 .data = &block_dump,
1441 .maxlen = sizeof(block_dump),
1443 .proc_handler = proc_dointvec,
1447 .procname = "vfs_cache_pressure",
1448 .data = &sysctl_vfs_cache_pressure,
1449 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1451 .proc_handler = proc_dointvec,
1454 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1456 .procname = "legacy_va_layout",
1457 .data = &sysctl_legacy_va_layout,
1458 .maxlen = sizeof(sysctl_legacy_va_layout),
1460 .proc_handler = proc_dointvec,
1466 .procname = "zone_reclaim_mode",
1467 .data = &zone_reclaim_mode,
1468 .maxlen = sizeof(zone_reclaim_mode),
1470 .proc_handler = proc_dointvec,
1474 .procname = "min_unmapped_ratio",
1475 .data = &sysctl_min_unmapped_ratio,
1476 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1478 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1480 .extra2 = &one_hundred,
1483 .procname = "min_slab_ratio",
1484 .data = &sysctl_min_slab_ratio,
1485 .maxlen = sizeof(sysctl_min_slab_ratio),
1487 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1489 .extra2 = &one_hundred,
1494 .procname = "stat_interval",
1495 .data = &sysctl_stat_interval,
1496 .maxlen = sizeof(sysctl_stat_interval),
1498 .proc_handler = proc_dointvec_jiffies,
1503 .procname = "mmap_min_addr",
1504 .data = &dac_mmap_min_addr,
1505 .maxlen = sizeof(unsigned long),
1507 .proc_handler = mmap_min_addr_handler,
1512 .procname = "numa_zonelist_order",
1513 .data = &numa_zonelist_order,
1514 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1516 .proc_handler = numa_zonelist_order_handler,
1519 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1520 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1522 .procname = "vdso_enabled",
1523 #ifdef CONFIG_X86_32
1524 .data = &vdso32_enabled,
1525 .maxlen = sizeof(vdso32_enabled),
1527 .data = &vdso_enabled,
1528 .maxlen = sizeof(vdso_enabled),
1531 .proc_handler = proc_dointvec,
1535 #ifdef CONFIG_HIGHMEM
1537 .procname = "highmem_is_dirtyable",
1538 .data = &vm_highmem_is_dirtyable,
1539 .maxlen = sizeof(vm_highmem_is_dirtyable),
1541 .proc_handler = proc_dointvec_minmax,
1546 #ifdef CONFIG_MEMORY_FAILURE
1548 .procname = "memory_failure_early_kill",
1549 .data = &sysctl_memory_failure_early_kill,
1550 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1552 .proc_handler = proc_dointvec_minmax,
1557 .procname = "memory_failure_recovery",
1558 .data = &sysctl_memory_failure_recovery,
1559 .maxlen = sizeof(sysctl_memory_failure_recovery),
1561 .proc_handler = proc_dointvec_minmax,
1567 .procname = "user_reserve_kbytes",
1568 .data = &sysctl_user_reserve_kbytes,
1569 .maxlen = sizeof(sysctl_user_reserve_kbytes),
1571 .proc_handler = proc_doulongvec_minmax,
1574 .procname = "admin_reserve_kbytes",
1575 .data = &sysctl_admin_reserve_kbytes,
1576 .maxlen = sizeof(sysctl_admin_reserve_kbytes),
1578 .proc_handler = proc_doulongvec_minmax,
1580 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
1582 .procname = "mmap_rnd_bits",
1583 .data = &mmap_rnd_bits,
1584 .maxlen = sizeof(mmap_rnd_bits),
1586 .proc_handler = proc_dointvec_minmax,
1587 .extra1 = (void *)&mmap_rnd_bits_min,
1588 .extra2 = (void *)&mmap_rnd_bits_max,
1591 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
1593 .procname = "mmap_rnd_compat_bits",
1594 .data = &mmap_rnd_compat_bits,
1595 .maxlen = sizeof(mmap_rnd_compat_bits),
1597 .proc_handler = proc_dointvec_minmax,
1598 .extra1 = (void *)&mmap_rnd_compat_bits_min,
1599 .extra2 = (void *)&mmap_rnd_compat_bits_max,
1605 static struct ctl_table fs_table[] = {
1607 .procname = "inode-nr",
1608 .data = &inodes_stat,
1609 .maxlen = 2*sizeof(long),
1611 .proc_handler = proc_nr_inodes,
1614 .procname = "inode-state",
1615 .data = &inodes_stat,
1616 .maxlen = 7*sizeof(long),
1618 .proc_handler = proc_nr_inodes,
1621 .procname = "file-nr",
1622 .data = &files_stat,
1623 .maxlen = sizeof(files_stat),
1625 .proc_handler = proc_nr_files,
1628 .procname = "file-max",
1629 .data = &files_stat.max_files,
1630 .maxlen = sizeof(files_stat.max_files),
1632 .proc_handler = proc_doulongvec_minmax,
1635 .procname = "nr_open",
1636 .data = &sysctl_nr_open,
1637 .maxlen = sizeof(int),
1639 .proc_handler = proc_dointvec_minmax,
1640 .extra1 = &sysctl_nr_open_min,
1641 .extra2 = &sysctl_nr_open_max,
1644 .procname = "dentry-state",
1645 .data = &dentry_stat,
1646 .maxlen = 6*sizeof(long),
1648 .proc_handler = proc_nr_dentry,
1651 .procname = "overflowuid",
1652 .data = &fs_overflowuid,
1653 .maxlen = sizeof(int),
1655 .proc_handler = proc_dointvec_minmax,
1656 .extra1 = &minolduid,
1657 .extra2 = &maxolduid,
1660 .procname = "overflowgid",
1661 .data = &fs_overflowgid,
1662 .maxlen = sizeof(int),
1664 .proc_handler = proc_dointvec_minmax,
1665 .extra1 = &minolduid,
1666 .extra2 = &maxolduid,
1668 #ifdef CONFIG_FILE_LOCKING
1670 .procname = "leases-enable",
1671 .data = &leases_enable,
1672 .maxlen = sizeof(int),
1674 .proc_handler = proc_dointvec,
1677 #ifdef CONFIG_DNOTIFY
1679 .procname = "dir-notify-enable",
1680 .data = &dir_notify_enable,
1681 .maxlen = sizeof(int),
1683 .proc_handler = proc_dointvec,
1687 #ifdef CONFIG_FILE_LOCKING
1689 .procname = "lease-break-time",
1690 .data = &lease_break_time,
1691 .maxlen = sizeof(int),
1693 .proc_handler = proc_dointvec,
1698 .procname = "aio-nr",
1700 .maxlen = sizeof(aio_nr),
1702 .proc_handler = proc_doulongvec_minmax,
1705 .procname = "aio-max-nr",
1706 .data = &aio_max_nr,
1707 .maxlen = sizeof(aio_max_nr),
1709 .proc_handler = proc_doulongvec_minmax,
1711 #endif /* CONFIG_AIO */
1712 #ifdef CONFIG_INOTIFY_USER
1714 .procname = "inotify",
1716 .child = inotify_table,
1721 .procname = "epoll",
1723 .child = epoll_table,
1728 .procname = "protected_symlinks",
1729 .data = &sysctl_protected_symlinks,
1730 .maxlen = sizeof(int),
1732 .proc_handler = proc_dointvec_minmax,
1737 .procname = "protected_hardlinks",
1738 .data = &sysctl_protected_hardlinks,
1739 .maxlen = sizeof(int),
1741 .proc_handler = proc_dointvec_minmax,
1746 .procname = "suid_dumpable",
1747 .data = &suid_dumpable,
1748 .maxlen = sizeof(int),
1750 .proc_handler = proc_dointvec_minmax_coredump,
1754 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1756 .procname = "binfmt_misc",
1758 .child = sysctl_mount_point,
1762 .procname = "pipe-max-size",
1763 .data = &pipe_max_size,
1764 .maxlen = sizeof(int),
1766 .proc_handler = &pipe_proc_fn,
1767 .extra1 = &pipe_min_size,
1772 static struct ctl_table debug_table[] = {
1773 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1775 .procname = "exception-trace",
1776 .data = &show_unhandled_signals,
1777 .maxlen = sizeof(int),
1779 .proc_handler = proc_dointvec
1782 #if defined(CONFIG_OPTPROBES)
1784 .procname = "kprobes-optimization",
1785 .data = &sysctl_kprobes_optimization,
1786 .maxlen = sizeof(int),
1788 .proc_handler = proc_kprobes_optimization_handler,
1796 static struct ctl_table dev_table[] = {
1800 int __init sysctl_init(void)
1802 struct ctl_table_header *hdr;
1804 hdr = register_sysctl_table(sysctl_base_table);
1805 kmemleak_not_leak(hdr);
1809 #endif /* CONFIG_SYSCTL */
1815 #ifdef CONFIG_PROC_SYSCTL
1817 static int _proc_do_string(char *data, int maxlen, int write,
1818 char __user *buffer,
1819 size_t *lenp, loff_t *ppos)
1825 if (!data || !maxlen || !*lenp) {
1831 if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
1832 /* Only continue writes not past the end of buffer. */
1834 if (len > maxlen - 1)
1841 /* Start writing from beginning of buffer. */
1847 while ((p - buffer) < *lenp && len < maxlen - 1) {
1848 if (get_user(c, p++))
1850 if (c == 0 || c == '\n')
1871 if (copy_to_user(buffer, data, len))
1874 if (put_user('\n', buffer + len))
1884 static void warn_sysctl_write(struct ctl_table *table)
1886 pr_warn_once("%s wrote to %s when file position was not 0!\n"
1887 "This will not be supported in the future. To silence this\n"
1888 "warning, set kernel.sysctl_writes_strict = -1\n",
1889 current->comm, table->procname);
1893 * proc_dostring - read a string sysctl
1894 * @table: the sysctl table
1895 * @write: %TRUE if this is a write to the sysctl file
1896 * @buffer: the user buffer
1897 * @lenp: the size of the user buffer
1898 * @ppos: file position
1900 * Reads/writes a string from/to the user buffer. If the kernel
1901 * buffer provided is not large enough to hold the string, the
1902 * string is truncated. The copied string is %NULL-terminated.
1903 * If the string is being read by the user process, it is copied
1904 * and a newline '\n' is added. It is truncated if the buffer is
1907 * Returns 0 on success.
1909 int proc_dostring(struct ctl_table *table, int write,
1910 void __user *buffer, size_t *lenp, loff_t *ppos)
1912 if (write && *ppos && sysctl_writes_strict == SYSCTL_WRITES_WARN)
1913 warn_sysctl_write(table);
1915 return _proc_do_string((char *)(table->data), table->maxlen, write,
1916 (char __user *)buffer, lenp, ppos);
1919 static size_t proc_skip_spaces(char **buf)
1922 char *tmp = skip_spaces(*buf);
1928 static void proc_skip_char(char **buf, size_t *size, const char v)
1938 #define TMPBUFLEN 22
1940 * proc_get_long - reads an ASCII formatted integer from a user buffer
1942 * @buf: a kernel buffer
1943 * @size: size of the kernel buffer
1944 * @val: this is where the number will be stored
1945 * @neg: set to %TRUE if number is negative
1946 * @perm_tr: a vector which contains the allowed trailers
1947 * @perm_tr_len: size of the perm_tr vector
1948 * @tr: pointer to store the trailer character
1950 * In case of success %0 is returned and @buf and @size are updated with
1951 * the amount of bytes read. If @tr is non-NULL and a trailing
1952 * character exists (size is non-zero after returning from this
1953 * function), @tr is updated with the trailing character.
1955 static int proc_get_long(char **buf, size_t *size,
1956 unsigned long *val, bool *neg,
1957 const char *perm_tr, unsigned perm_tr_len, char *tr)
1960 char *p, tmp[TMPBUFLEN];
1966 if (len > TMPBUFLEN - 1)
1967 len = TMPBUFLEN - 1;
1969 memcpy(tmp, *buf, len);
1973 if (*p == '-' && *size > 1) {
1981 *val = simple_strtoul(p, &p, 0);
1985 /* We don't know if the next char is whitespace thus we may accept
1986 * invalid integers (e.g. 1234...a) or two integers instead of one
1987 * (e.g. 123...1). So lets not allow such large numbers. */
1988 if (len == TMPBUFLEN - 1)
1991 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
1994 if (tr && (len < *size))
2004 * proc_put_long - converts an integer to a decimal ASCII formatted string
2006 * @buf: the user buffer
2007 * @size: the size of the user buffer
2008 * @val: the integer to be converted
2009 * @neg: sign of the number, %TRUE for negative
2011 * In case of success %0 is returned and @buf and @size are updated with
2012 * the amount of bytes written.
2014 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2018 char tmp[TMPBUFLEN], *p = tmp;
2020 sprintf(p, "%s%lu", neg ? "-" : "", val);
2024 if (copy_to_user(*buf, tmp, len))
2032 static int proc_put_char(void __user **buf, size_t *size, char c)
2035 char __user **buffer = (char __user **)buf;
2036 if (put_user(c, *buffer))
2038 (*size)--, (*buffer)++;
2044 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2046 int write, void *data)
2050 if (*lvalp > (unsigned long) INT_MAX + 1)
2054 if (*lvalp > (unsigned long) INT_MAX)
2062 *lvalp = -(unsigned long)val;
2065 *lvalp = (unsigned long)val;
2071 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2073 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2074 int write, void __user *buffer,
2075 size_t *lenp, loff_t *ppos,
2076 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2077 int write, void *data),
2080 int *i, vleft, first = 1, err = 0;
2081 unsigned long page = 0;
2085 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2090 i = (int *) tbl_data;
2091 vleft = table->maxlen / sizeof(*i);
2095 conv = do_proc_dointvec_conv;
2099 switch (sysctl_writes_strict) {
2100 case SYSCTL_WRITES_STRICT:
2102 case SYSCTL_WRITES_WARN:
2103 warn_sysctl_write(table);
2110 if (left > PAGE_SIZE - 1)
2111 left = PAGE_SIZE - 1;
2112 page = __get_free_page(GFP_TEMPORARY);
2113 kbuf = (char *) page;
2116 if (copy_from_user(kbuf, buffer, left)) {
2123 for (; left && vleft--; i++, first=0) {
2128 left -= proc_skip_spaces(&kbuf);
2132 err = proc_get_long(&kbuf, &left, &lval, &neg,
2134 sizeof(proc_wspace_sep), NULL);
2137 if (conv(&neg, &lval, i, 1, data)) {
2142 if (conv(&neg, &lval, i, 0, data)) {
2147 err = proc_put_char(&buffer, &left, '\t');
2150 err = proc_put_long(&buffer, &left, lval, neg);
2156 if (!write && !first && left && !err)
2157 err = proc_put_char(&buffer, &left, '\n');
2158 if (write && !err && left)
2159 left -= proc_skip_spaces(&kbuf);
2164 return err ? : -EINVAL;
2172 static int do_proc_dointvec(struct ctl_table *table, int write,
2173 void __user *buffer, size_t *lenp, loff_t *ppos,
2174 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2175 int write, void *data),
2178 return __do_proc_dointvec(table->data, table, write,
2179 buffer, lenp, ppos, conv, data);
2183 * proc_dointvec - read a vector of integers
2184 * @table: the sysctl table
2185 * @write: %TRUE if this is a write to the sysctl file
2186 * @buffer: the user buffer
2187 * @lenp: the size of the user buffer
2188 * @ppos: file position
2190 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2191 * values from/to the user buffer, treated as an ASCII string.
2193 * Returns 0 on success.
2195 int proc_dointvec(struct ctl_table *table, int write,
2196 void __user *buffer, size_t *lenp, loff_t *ppos)
2198 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2203 * Taint values can only be increased
2204 * This means we can safely use a temporary.
2206 static int proc_taint(struct ctl_table *table, int write,
2207 void __user *buffer, size_t *lenp, loff_t *ppos)
2210 unsigned long tmptaint = get_taint();
2213 if (write && !capable(CAP_SYS_ADMIN))
2218 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2224 * Poor man's atomic or. Not worth adding a primitive
2225 * to everyone's atomic.h for this
2228 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2229 if ((tmptaint >> i) & 1)
2230 add_taint(i, LOCKDEP_STILL_OK);
2237 #ifdef CONFIG_PRINTK
2238 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2239 void __user *buffer, size_t *lenp, loff_t *ppos)
2241 if (write && !capable(CAP_SYS_ADMIN))
2244 return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2248 struct do_proc_dointvec_minmax_conv_param {
2253 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2255 int write, void *data)
2257 struct do_proc_dointvec_minmax_conv_param *param = data;
2259 int val = *negp ? -*lvalp : *lvalp;
2260 if ((param->min && *param->min > val) ||
2261 (param->max && *param->max < val))
2268 *lvalp = -(unsigned long)val;
2271 *lvalp = (unsigned long)val;
2278 * proc_dointvec_minmax - read a vector of integers with min/max values
2279 * @table: the sysctl table
2280 * @write: %TRUE if this is a write to the sysctl file
2281 * @buffer: the user buffer
2282 * @lenp: the size of the user buffer
2283 * @ppos: file position
2285 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2286 * values from/to the user buffer, treated as an ASCII string.
2288 * This routine will ensure the values are within the range specified by
2289 * table->extra1 (min) and table->extra2 (max).
2291 * Returns 0 on success.
2293 int proc_dointvec_minmax(struct ctl_table *table, int write,
2294 void __user *buffer, size_t *lenp, loff_t *ppos)
2296 struct do_proc_dointvec_minmax_conv_param param = {
2297 .min = (int *) table->extra1,
2298 .max = (int *) table->extra2,
2300 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2301 do_proc_dointvec_minmax_conv, ¶m);
2304 static void validate_coredump_safety(void)
2306 #ifdef CONFIG_COREDUMP
2307 if (suid_dumpable == SUID_DUMP_ROOT &&
2308 core_pattern[0] != '/' && core_pattern[0] != '|') {
2309 printk(KERN_WARNING "Unsafe core_pattern used with "\
2310 "suid_dumpable=2. Pipe handler or fully qualified "\
2311 "core dump path required.\n");
2316 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2317 void __user *buffer, size_t *lenp, loff_t *ppos)
2319 int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2321 validate_coredump_safety();
2325 #ifdef CONFIG_COREDUMP
2326 static int proc_dostring_coredump(struct ctl_table *table, int write,
2327 void __user *buffer, size_t *lenp, loff_t *ppos)
2329 int error = proc_dostring(table, write, buffer, lenp, ppos);
2331 validate_coredump_safety();
2336 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2337 void __user *buffer,
2338 size_t *lenp, loff_t *ppos,
2339 unsigned long convmul,
2340 unsigned long convdiv)
2342 unsigned long *i, *min, *max;
2343 int vleft, first = 1, err = 0;
2344 unsigned long page = 0;
2348 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2353 i = (unsigned long *) data;
2354 min = (unsigned long *) table->extra1;
2355 max = (unsigned long *) table->extra2;
2356 vleft = table->maxlen / sizeof(unsigned long);
2361 switch (sysctl_writes_strict) {
2362 case SYSCTL_WRITES_STRICT:
2364 case SYSCTL_WRITES_WARN:
2365 warn_sysctl_write(table);
2372 if (left > PAGE_SIZE - 1)
2373 left = PAGE_SIZE - 1;
2374 page = __get_free_page(GFP_TEMPORARY);
2375 kbuf = (char *) page;
2378 if (copy_from_user(kbuf, buffer, left)) {
2385 for (; left && vleft--; i++, first = 0) {
2391 left -= proc_skip_spaces(&kbuf);
2393 err = proc_get_long(&kbuf, &left, &val, &neg,
2395 sizeof(proc_wspace_sep), NULL);
2400 if ((min && val < *min) || (max && val > *max))
2404 val = convdiv * (*i) / convmul;
2406 err = proc_put_char(&buffer, &left, '\t');
2410 err = proc_put_long(&buffer, &left, val, false);
2416 if (!write && !first && left && !err)
2417 err = proc_put_char(&buffer, &left, '\n');
2419 left -= proc_skip_spaces(&kbuf);
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)) {
2684 unsigned long page = 0;
2687 if (left > PAGE_SIZE - 1)
2688 left = PAGE_SIZE - 1;
2690 page = __get_free_page(GFP_TEMPORARY);
2691 kbuf = (char *) page;
2694 if (copy_from_user(kbuf, buffer, left)) {
2700 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2706 proc_skip_char(&kbuf, &left, '\n');
2707 while (!err && left) {
2708 unsigned long val_a, val_b;
2711 err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2715 if (val_a >= bitmap_len || neg) {
2727 err = proc_get_long(&kbuf, &left, &val_b,
2728 &neg, tr_b, sizeof(tr_b),
2732 if (val_b >= bitmap_len || neg ||
2743 bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
2745 proc_skip_char(&kbuf, &left, '\n');
2749 unsigned long bit_a, bit_b = 0;
2752 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2753 if (bit_a >= bitmap_len)
2755 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2759 err = proc_put_char(&buffer, &left, ',');
2763 err = proc_put_long(&buffer, &left, bit_a, false);
2766 if (bit_a != bit_b) {
2767 err = proc_put_char(&buffer, &left, '-');
2770 err = proc_put_long(&buffer, &left, bit_b, false);
2778 err = proc_put_char(&buffer, &left, '\n');
2784 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2786 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
2798 #else /* CONFIG_PROC_SYSCTL */
2800 int proc_dostring(struct ctl_table *table, int write,
2801 void __user *buffer, size_t *lenp, loff_t *ppos)
2806 int proc_dointvec(struct ctl_table *table, int write,
2807 void __user *buffer, size_t *lenp, loff_t *ppos)
2812 int proc_dointvec_minmax(struct ctl_table *table, int write,
2813 void __user *buffer, size_t *lenp, loff_t *ppos)
2818 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2819 void __user *buffer, size_t *lenp, loff_t *ppos)
2824 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2825 void __user *buffer, size_t *lenp, loff_t *ppos)
2830 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2831 void __user *buffer, size_t *lenp, loff_t *ppos)
2836 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2837 void __user *buffer, size_t *lenp, loff_t *ppos)
2842 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2843 void __user *buffer,
2844 size_t *lenp, loff_t *ppos)
2850 #endif /* CONFIG_PROC_SYSCTL */
2853 * No sense putting this after each symbol definition, twice,
2854 * exception granted :-)
2856 EXPORT_SYMBOL(proc_dointvec);
2857 EXPORT_SYMBOL(proc_dointvec_jiffies);
2858 EXPORT_SYMBOL(proc_dointvec_minmax);
2859 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2860 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2861 EXPORT_SYMBOL(proc_dostring);
2862 EXPORT_SYMBOL(proc_doulongvec_minmax);
2863 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);