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_SCHED_TUNE
440 .procname = "sched_cfs_boost",
441 .data = &sysctl_sched_cfs_boost,
442 .maxlen = sizeof(sysctl_sched_cfs_boost),
443 #ifdef CONFIG_CGROUP_SCHEDTUNE
448 .proc_handler = &sysctl_sched_cfs_boost_handler,
450 .extra2 = &one_hundred,
453 #ifdef CONFIG_PROVE_LOCKING
455 .procname = "prove_locking",
456 .data = &prove_locking,
457 .maxlen = sizeof(int),
459 .proc_handler = proc_dointvec,
462 #ifdef CONFIG_LOCK_STAT
464 .procname = "lock_stat",
466 .maxlen = sizeof(int),
468 .proc_handler = proc_dointvec,
473 .data = &panic_timeout,
474 .maxlen = sizeof(int),
476 .proc_handler = proc_dointvec,
478 #ifdef CONFIG_COREDUMP
480 .procname = "core_uses_pid",
481 .data = &core_uses_pid,
482 .maxlen = sizeof(int),
484 .proc_handler = proc_dointvec,
487 .procname = "core_pattern",
488 .data = core_pattern,
489 .maxlen = CORENAME_MAX_SIZE,
491 .proc_handler = proc_dostring_coredump,
494 .procname = "core_pipe_limit",
495 .data = &core_pipe_limit,
496 .maxlen = sizeof(unsigned int),
498 .proc_handler = proc_dointvec,
501 #ifdef CONFIG_PROC_SYSCTL
503 .procname = "tainted",
504 .maxlen = sizeof(long),
506 .proc_handler = proc_taint,
509 .procname = "sysctl_writes_strict",
510 .data = &sysctl_writes_strict,
511 .maxlen = sizeof(int),
513 .proc_handler = proc_dointvec_minmax,
518 #ifdef CONFIG_LATENCYTOP
520 .procname = "latencytop",
521 .data = &latencytop_enabled,
522 .maxlen = sizeof(int),
524 .proc_handler = proc_dointvec,
527 #ifdef CONFIG_BLK_DEV_INITRD
529 .procname = "real-root-dev",
530 .data = &real_root_dev,
531 .maxlen = sizeof(int),
533 .proc_handler = proc_dointvec,
537 .procname = "print-fatal-signals",
538 .data = &print_fatal_signals,
539 .maxlen = sizeof(int),
541 .proc_handler = proc_dointvec,
545 .procname = "reboot-cmd",
546 .data = reboot_command,
549 .proc_handler = proc_dostring,
552 .procname = "stop-a",
553 .data = &stop_a_enabled,
554 .maxlen = sizeof (int),
556 .proc_handler = proc_dointvec,
559 .procname = "scons-poweroff",
560 .data = &scons_pwroff,
561 .maxlen = sizeof (int),
563 .proc_handler = proc_dointvec,
566 #ifdef CONFIG_SPARC64
568 .procname = "tsb-ratio",
569 .data = &sysctl_tsb_ratio,
570 .maxlen = sizeof (int),
572 .proc_handler = proc_dointvec,
577 .procname = "soft-power",
578 .data = &pwrsw_enabled,
579 .maxlen = sizeof (int),
581 .proc_handler = proc_dointvec,
584 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
586 .procname = "unaligned-trap",
587 .data = &unaligned_enabled,
588 .maxlen = sizeof (int),
590 .proc_handler = proc_dointvec,
594 .procname = "ctrl-alt-del",
596 .maxlen = sizeof(int),
598 .proc_handler = proc_dointvec,
600 #ifdef CONFIG_FUNCTION_TRACER
602 .procname = "ftrace_enabled",
603 .data = &ftrace_enabled,
604 .maxlen = sizeof(int),
606 .proc_handler = ftrace_enable_sysctl,
609 #ifdef CONFIG_STACK_TRACER
611 .procname = "stack_tracer_enabled",
612 .data = &stack_tracer_enabled,
613 .maxlen = sizeof(int),
615 .proc_handler = stack_trace_sysctl,
618 #ifdef CONFIG_TRACING
620 .procname = "ftrace_dump_on_oops",
621 .data = &ftrace_dump_on_oops,
622 .maxlen = sizeof(int),
624 .proc_handler = proc_dointvec,
627 .procname = "traceoff_on_warning",
628 .data = &__disable_trace_on_warning,
629 .maxlen = sizeof(__disable_trace_on_warning),
631 .proc_handler = proc_dointvec,
634 .procname = "tracepoint_printk",
635 .data = &tracepoint_printk,
636 .maxlen = sizeof(tracepoint_printk),
638 .proc_handler = proc_dointvec,
641 #ifdef CONFIG_KEXEC_CORE
643 .procname = "kexec_load_disabled",
644 .data = &kexec_load_disabled,
645 .maxlen = sizeof(int),
647 /* only handle a transition from default "0" to "1" */
648 .proc_handler = proc_dointvec_minmax,
653 #ifdef CONFIG_MODULES
655 .procname = "modprobe",
656 .data = &modprobe_path,
657 .maxlen = KMOD_PATH_LEN,
659 .proc_handler = proc_dostring,
662 .procname = "modules_disabled",
663 .data = &modules_disabled,
664 .maxlen = sizeof(int),
666 /* only handle a transition from default "0" to "1" */
667 .proc_handler = proc_dointvec_minmax,
672 #ifdef CONFIG_UEVENT_HELPER
674 .procname = "hotplug",
675 .data = &uevent_helper,
676 .maxlen = UEVENT_HELPER_PATH_LEN,
678 .proc_handler = proc_dostring,
681 #ifdef CONFIG_CHR_DEV_SG
683 .procname = "sg-big-buff",
684 .data = &sg_big_buff,
685 .maxlen = sizeof (int),
687 .proc_handler = proc_dointvec,
690 #ifdef CONFIG_BSD_PROCESS_ACCT
694 .maxlen = 3*sizeof(int),
696 .proc_handler = proc_dointvec,
699 #ifdef CONFIG_MAGIC_SYSRQ
702 .data = &__sysrq_enabled,
703 .maxlen = sizeof (int),
705 .proc_handler = sysrq_sysctl_handler,
708 #ifdef CONFIG_PROC_SYSCTL
710 .procname = "cad_pid",
712 .maxlen = sizeof (int),
714 .proc_handler = proc_do_cad_pid,
718 .procname = "threads-max",
720 .maxlen = sizeof(int),
722 .proc_handler = sysctl_max_threads,
725 .procname = "random",
727 .child = random_table,
730 .procname = "usermodehelper",
732 .child = usermodehelper_table,
735 .procname = "overflowuid",
736 .data = &overflowuid,
737 .maxlen = sizeof(int),
739 .proc_handler = proc_dointvec_minmax,
740 .extra1 = &minolduid,
741 .extra2 = &maxolduid,
744 .procname = "overflowgid",
745 .data = &overflowgid,
746 .maxlen = sizeof(int),
748 .proc_handler = proc_dointvec_minmax,
749 .extra1 = &minolduid,
750 .extra2 = &maxolduid,
753 #ifdef CONFIG_MATHEMU
755 .procname = "ieee_emulation_warnings",
756 .data = &sysctl_ieee_emulation_warnings,
757 .maxlen = sizeof(int),
759 .proc_handler = proc_dointvec,
763 .procname = "userprocess_debug",
764 .data = &show_unhandled_signals,
765 .maxlen = sizeof(int),
767 .proc_handler = proc_dointvec,
771 .procname = "pid_max",
773 .maxlen = sizeof (int),
775 .proc_handler = proc_dointvec_minmax,
776 .extra1 = &pid_max_min,
777 .extra2 = &pid_max_max,
780 .procname = "panic_on_oops",
781 .data = &panic_on_oops,
782 .maxlen = sizeof(int),
784 .proc_handler = proc_dointvec,
786 #if defined CONFIG_PRINTK
788 .procname = "printk",
789 .data = &console_loglevel,
790 .maxlen = 4*sizeof(int),
792 .proc_handler = proc_dointvec,
795 .procname = "printk_ratelimit",
796 .data = &printk_ratelimit_state.interval,
797 .maxlen = sizeof(int),
799 .proc_handler = proc_dointvec_jiffies,
802 .procname = "printk_ratelimit_burst",
803 .data = &printk_ratelimit_state.burst,
804 .maxlen = sizeof(int),
806 .proc_handler = proc_dointvec,
809 .procname = "printk_delay",
810 .data = &printk_delay_msec,
811 .maxlen = sizeof(int),
813 .proc_handler = proc_dointvec_minmax,
815 .extra2 = &ten_thousand,
818 .procname = "dmesg_restrict",
819 .data = &dmesg_restrict,
820 .maxlen = sizeof(int),
822 .proc_handler = proc_dointvec_minmax_sysadmin,
827 .procname = "kptr_restrict",
828 .data = &kptr_restrict,
829 .maxlen = sizeof(int),
831 .proc_handler = proc_dointvec_minmax_sysadmin,
837 .procname = "ngroups_max",
838 .data = &ngroups_max,
839 .maxlen = sizeof (int),
841 .proc_handler = proc_dointvec,
844 .procname = "cap_last_cap",
845 .data = (void *)&cap_last_cap,
846 .maxlen = sizeof(int),
848 .proc_handler = proc_dointvec,
850 #if defined(CONFIG_LOCKUP_DETECTOR)
852 .procname = "watchdog",
853 .data = &watchdog_user_enabled,
854 .maxlen = sizeof (int),
856 .proc_handler = proc_watchdog,
861 .procname = "watchdog_thresh",
862 .data = &watchdog_thresh,
863 .maxlen = sizeof(int),
865 .proc_handler = proc_watchdog_thresh,
870 .procname = "nmi_watchdog",
871 .data = &nmi_watchdog_enabled,
872 .maxlen = sizeof (int),
874 .proc_handler = proc_nmi_watchdog,
876 #if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)
883 .procname = "soft_watchdog",
884 .data = &soft_watchdog_enabled,
885 .maxlen = sizeof (int),
887 .proc_handler = proc_soft_watchdog,
892 .procname = "watchdog_cpumask",
893 .data = &watchdog_cpumask_bits,
896 .proc_handler = proc_watchdog_cpumask,
899 .procname = "softlockup_panic",
900 .data = &softlockup_panic,
901 .maxlen = sizeof(int),
903 .proc_handler = proc_dointvec_minmax,
907 #ifdef CONFIG_HARDLOCKUP_DETECTOR
909 .procname = "hardlockup_panic",
910 .data = &hardlockup_panic,
911 .maxlen = sizeof(int),
913 .proc_handler = proc_dointvec_minmax,
920 .procname = "softlockup_all_cpu_backtrace",
921 .data = &sysctl_softlockup_all_cpu_backtrace,
922 .maxlen = sizeof(int),
924 .proc_handler = proc_dointvec_minmax,
929 .procname = "hardlockup_all_cpu_backtrace",
930 .data = &sysctl_hardlockup_all_cpu_backtrace,
931 .maxlen = sizeof(int),
933 .proc_handler = proc_dointvec_minmax,
937 #endif /* CONFIG_SMP */
939 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
941 .procname = "unknown_nmi_panic",
942 .data = &unknown_nmi_panic,
943 .maxlen = sizeof (int),
945 .proc_handler = proc_dointvec,
948 #if defined(CONFIG_X86)
950 .procname = "panic_on_unrecovered_nmi",
951 .data = &panic_on_unrecovered_nmi,
952 .maxlen = sizeof(int),
954 .proc_handler = proc_dointvec,
957 .procname = "panic_on_io_nmi",
958 .data = &panic_on_io_nmi,
959 .maxlen = sizeof(int),
961 .proc_handler = proc_dointvec,
963 #ifdef CONFIG_DEBUG_STACKOVERFLOW
965 .procname = "panic_on_stackoverflow",
966 .data = &sysctl_panic_on_stackoverflow,
967 .maxlen = sizeof(int),
969 .proc_handler = proc_dointvec,
973 .procname = "bootloader_type",
974 .data = &bootloader_type,
975 .maxlen = sizeof (int),
977 .proc_handler = proc_dointvec,
980 .procname = "bootloader_version",
981 .data = &bootloader_version,
982 .maxlen = sizeof (int),
984 .proc_handler = proc_dointvec,
987 .procname = "kstack_depth_to_print",
988 .data = &kstack_depth_to_print,
989 .maxlen = sizeof(int),
991 .proc_handler = proc_dointvec,
994 .procname = "io_delay_type",
995 .data = &io_delay_type,
996 .maxlen = sizeof(int),
998 .proc_handler = proc_dointvec,
1001 #if defined(CONFIG_MMU)
1003 .procname = "randomize_va_space",
1004 .data = &randomize_va_space,
1005 .maxlen = sizeof(int),
1007 .proc_handler = proc_dointvec,
1010 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1012 .procname = "spin_retry",
1013 .data = &spin_retry,
1014 .maxlen = sizeof (int),
1016 .proc_handler = proc_dointvec,
1019 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1021 .procname = "acpi_video_flags",
1022 .data = &acpi_realmode_flags,
1023 .maxlen = sizeof (unsigned long),
1025 .proc_handler = proc_doulongvec_minmax,
1028 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1030 .procname = "ignore-unaligned-usertrap",
1031 .data = &no_unaligned_warning,
1032 .maxlen = sizeof (int),
1034 .proc_handler = proc_dointvec,
1039 .procname = "unaligned-dump-stack",
1040 .data = &unaligned_dump_stack,
1041 .maxlen = sizeof (int),
1043 .proc_handler = proc_dointvec,
1046 #ifdef CONFIG_DETECT_HUNG_TASK
1048 .procname = "hung_task_panic",
1049 .data = &sysctl_hung_task_panic,
1050 .maxlen = sizeof(int),
1052 .proc_handler = proc_dointvec_minmax,
1057 .procname = "hung_task_check_count",
1058 .data = &sysctl_hung_task_check_count,
1059 .maxlen = sizeof(int),
1061 .proc_handler = proc_dointvec_minmax,
1065 .procname = "hung_task_timeout_secs",
1066 .data = &sysctl_hung_task_timeout_secs,
1067 .maxlen = sizeof(unsigned long),
1069 .proc_handler = proc_dohung_task_timeout_secs,
1070 .extra2 = &hung_task_timeout_max,
1073 .procname = "hung_task_warnings",
1074 .data = &sysctl_hung_task_warnings,
1075 .maxlen = sizeof(int),
1077 .proc_handler = proc_dointvec_minmax,
1081 #ifdef CONFIG_COMPAT
1083 .procname = "compat-log",
1084 .data = &compat_log,
1085 .maxlen = sizeof (int),
1087 .proc_handler = proc_dointvec,
1090 #ifdef CONFIG_RT_MUTEXES
1092 .procname = "max_lock_depth",
1093 .data = &max_lock_depth,
1094 .maxlen = sizeof(int),
1096 .proc_handler = proc_dointvec,
1100 .procname = "poweroff_cmd",
1101 .data = &poweroff_cmd,
1102 .maxlen = POWEROFF_CMD_PATH_LEN,
1104 .proc_handler = proc_dostring,
1110 .child = key_sysctls,
1113 #ifdef CONFIG_PERF_EVENTS
1115 * User-space scripts rely on the existence of this file
1116 * as a feature check for perf_events being enabled.
1118 * So it's an ABI, do not remove!
1121 .procname = "perf_event_paranoid",
1122 .data = &sysctl_perf_event_paranoid,
1123 .maxlen = sizeof(sysctl_perf_event_paranoid),
1125 .proc_handler = proc_dointvec,
1128 .procname = "perf_event_mlock_kb",
1129 .data = &sysctl_perf_event_mlock,
1130 .maxlen = sizeof(sysctl_perf_event_mlock),
1132 .proc_handler = proc_dointvec,
1135 .procname = "perf_event_max_sample_rate",
1136 .data = &sysctl_perf_event_sample_rate,
1137 .maxlen = sizeof(sysctl_perf_event_sample_rate),
1139 .proc_handler = perf_proc_update_handler,
1143 .procname = "perf_cpu_time_max_percent",
1144 .data = &sysctl_perf_cpu_time_max_percent,
1145 .maxlen = sizeof(sysctl_perf_cpu_time_max_percent),
1147 .proc_handler = perf_cpu_time_max_percent_handler,
1149 .extra2 = &one_hundred,
1152 #ifdef CONFIG_KMEMCHECK
1154 .procname = "kmemcheck",
1155 .data = &kmemcheck_enabled,
1156 .maxlen = sizeof(int),
1158 .proc_handler = proc_dointvec,
1162 .procname = "panic_on_warn",
1163 .data = &panic_on_warn,
1164 .maxlen = sizeof(int),
1166 .proc_handler = proc_dointvec_minmax,
1170 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1172 .procname = "timer_migration",
1173 .data = &sysctl_timer_migration,
1174 .maxlen = sizeof(unsigned int),
1176 .proc_handler = timer_migration_handler,
1179 #ifdef CONFIG_BPF_SYSCALL
1181 .procname = "unprivileged_bpf_disabled",
1182 .data = &sysctl_unprivileged_bpf_disabled,
1183 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled),
1185 /* only handle a transition from default "0" to "1" */
1186 .proc_handler = proc_dointvec_minmax,
1194 static struct ctl_table vm_table[] = {
1196 .procname = "overcommit_memory",
1197 .data = &sysctl_overcommit_memory,
1198 .maxlen = sizeof(sysctl_overcommit_memory),
1200 .proc_handler = proc_dointvec_minmax,
1205 .procname = "panic_on_oom",
1206 .data = &sysctl_panic_on_oom,
1207 .maxlen = sizeof(sysctl_panic_on_oom),
1209 .proc_handler = proc_dointvec_minmax,
1214 .procname = "oom_kill_allocating_task",
1215 .data = &sysctl_oom_kill_allocating_task,
1216 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1218 .proc_handler = proc_dointvec,
1221 .procname = "oom_dump_tasks",
1222 .data = &sysctl_oom_dump_tasks,
1223 .maxlen = sizeof(sysctl_oom_dump_tasks),
1225 .proc_handler = proc_dointvec,
1228 .procname = "overcommit_ratio",
1229 .data = &sysctl_overcommit_ratio,
1230 .maxlen = sizeof(sysctl_overcommit_ratio),
1232 .proc_handler = overcommit_ratio_handler,
1235 .procname = "overcommit_kbytes",
1236 .data = &sysctl_overcommit_kbytes,
1237 .maxlen = sizeof(sysctl_overcommit_kbytes),
1239 .proc_handler = overcommit_kbytes_handler,
1242 .procname = "page-cluster",
1243 .data = &page_cluster,
1244 .maxlen = sizeof(int),
1246 .proc_handler = proc_dointvec_minmax,
1250 .procname = "dirty_background_ratio",
1251 .data = &dirty_background_ratio,
1252 .maxlen = sizeof(dirty_background_ratio),
1254 .proc_handler = dirty_background_ratio_handler,
1256 .extra2 = &one_hundred,
1259 .procname = "dirty_background_bytes",
1260 .data = &dirty_background_bytes,
1261 .maxlen = sizeof(dirty_background_bytes),
1263 .proc_handler = dirty_background_bytes_handler,
1267 .procname = "dirty_ratio",
1268 .data = &vm_dirty_ratio,
1269 .maxlen = sizeof(vm_dirty_ratio),
1271 .proc_handler = dirty_ratio_handler,
1273 .extra2 = &one_hundred,
1276 .procname = "dirty_bytes",
1277 .data = &vm_dirty_bytes,
1278 .maxlen = sizeof(vm_dirty_bytes),
1280 .proc_handler = dirty_bytes_handler,
1281 .extra1 = &dirty_bytes_min,
1284 .procname = "dirty_writeback_centisecs",
1285 .data = &dirty_writeback_interval,
1286 .maxlen = sizeof(dirty_writeback_interval),
1288 .proc_handler = dirty_writeback_centisecs_handler,
1291 .procname = "dirty_expire_centisecs",
1292 .data = &dirty_expire_interval,
1293 .maxlen = sizeof(dirty_expire_interval),
1295 .proc_handler = proc_dointvec_minmax,
1299 .procname = "dirtytime_expire_seconds",
1300 .data = &dirtytime_expire_interval,
1301 .maxlen = sizeof(dirty_expire_interval),
1303 .proc_handler = dirtytime_interval_handler,
1307 .procname = "nr_pdflush_threads",
1308 .mode = 0444 /* read-only */,
1309 .proc_handler = pdflush_proc_obsolete,
1312 .procname = "swappiness",
1313 .data = &vm_swappiness,
1314 .maxlen = sizeof(vm_swappiness),
1316 .proc_handler = proc_dointvec_minmax,
1318 .extra2 = &one_hundred,
1320 #ifdef CONFIG_HUGETLB_PAGE
1322 .procname = "nr_hugepages",
1324 .maxlen = sizeof(unsigned long),
1326 .proc_handler = hugetlb_sysctl_handler,
1330 .procname = "nr_hugepages_mempolicy",
1332 .maxlen = sizeof(unsigned long),
1334 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1338 .procname = "hugetlb_shm_group",
1339 .data = &sysctl_hugetlb_shm_group,
1340 .maxlen = sizeof(gid_t),
1342 .proc_handler = proc_dointvec,
1345 .procname = "hugepages_treat_as_movable",
1346 .data = &hugepages_treat_as_movable,
1347 .maxlen = sizeof(int),
1349 .proc_handler = proc_dointvec,
1352 .procname = "nr_overcommit_hugepages",
1354 .maxlen = sizeof(unsigned long),
1356 .proc_handler = hugetlb_overcommit_handler,
1360 .procname = "lowmem_reserve_ratio",
1361 .data = &sysctl_lowmem_reserve_ratio,
1362 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1364 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1367 .procname = "drop_caches",
1368 .data = &sysctl_drop_caches,
1369 .maxlen = sizeof(int),
1371 .proc_handler = drop_caches_sysctl_handler,
1375 #ifdef CONFIG_COMPACTION
1377 .procname = "compact_memory",
1378 .data = &sysctl_compact_memory,
1379 .maxlen = sizeof(int),
1381 .proc_handler = sysctl_compaction_handler,
1384 .procname = "extfrag_threshold",
1385 .data = &sysctl_extfrag_threshold,
1386 .maxlen = sizeof(int),
1388 .proc_handler = sysctl_extfrag_handler,
1389 .extra1 = &min_extfrag_threshold,
1390 .extra2 = &max_extfrag_threshold,
1393 .procname = "compact_unevictable_allowed",
1394 .data = &sysctl_compact_unevictable_allowed,
1395 .maxlen = sizeof(int),
1397 .proc_handler = proc_dointvec,
1402 #endif /* CONFIG_COMPACTION */
1404 .procname = "min_free_kbytes",
1405 .data = &min_free_kbytes,
1406 .maxlen = sizeof(min_free_kbytes),
1408 .proc_handler = min_free_kbytes_sysctl_handler,
1412 .procname = "extra_free_kbytes",
1413 .data = &extra_free_kbytes,
1414 .maxlen = sizeof(extra_free_kbytes),
1416 .proc_handler = min_free_kbytes_sysctl_handler,
1420 .procname = "percpu_pagelist_fraction",
1421 .data = &percpu_pagelist_fraction,
1422 .maxlen = sizeof(percpu_pagelist_fraction),
1424 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1429 .procname = "max_map_count",
1430 .data = &sysctl_max_map_count,
1431 .maxlen = sizeof(sysctl_max_map_count),
1433 .proc_handler = proc_dointvec_minmax,
1438 .procname = "nr_trim_pages",
1439 .data = &sysctl_nr_trim_pages,
1440 .maxlen = sizeof(sysctl_nr_trim_pages),
1442 .proc_handler = proc_dointvec_minmax,
1447 .procname = "laptop_mode",
1448 .data = &laptop_mode,
1449 .maxlen = sizeof(laptop_mode),
1451 .proc_handler = proc_dointvec_jiffies,
1454 .procname = "block_dump",
1455 .data = &block_dump,
1456 .maxlen = sizeof(block_dump),
1458 .proc_handler = proc_dointvec,
1462 .procname = "vfs_cache_pressure",
1463 .data = &sysctl_vfs_cache_pressure,
1464 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1466 .proc_handler = proc_dointvec,
1469 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1471 .procname = "legacy_va_layout",
1472 .data = &sysctl_legacy_va_layout,
1473 .maxlen = sizeof(sysctl_legacy_va_layout),
1475 .proc_handler = proc_dointvec,
1481 .procname = "zone_reclaim_mode",
1482 .data = &zone_reclaim_mode,
1483 .maxlen = sizeof(zone_reclaim_mode),
1485 .proc_handler = proc_dointvec,
1489 .procname = "min_unmapped_ratio",
1490 .data = &sysctl_min_unmapped_ratio,
1491 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1493 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1495 .extra2 = &one_hundred,
1498 .procname = "min_slab_ratio",
1499 .data = &sysctl_min_slab_ratio,
1500 .maxlen = sizeof(sysctl_min_slab_ratio),
1502 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1504 .extra2 = &one_hundred,
1509 .procname = "stat_interval",
1510 .data = &sysctl_stat_interval,
1511 .maxlen = sizeof(sysctl_stat_interval),
1513 .proc_handler = proc_dointvec_jiffies,
1518 .procname = "mmap_min_addr",
1519 .data = &dac_mmap_min_addr,
1520 .maxlen = sizeof(unsigned long),
1522 .proc_handler = mmap_min_addr_handler,
1527 .procname = "numa_zonelist_order",
1528 .data = &numa_zonelist_order,
1529 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1531 .proc_handler = numa_zonelist_order_handler,
1534 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1535 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1537 .procname = "vdso_enabled",
1538 #ifdef CONFIG_X86_32
1539 .data = &vdso32_enabled,
1540 .maxlen = sizeof(vdso32_enabled),
1542 .data = &vdso_enabled,
1543 .maxlen = sizeof(vdso_enabled),
1546 .proc_handler = proc_dointvec,
1550 #ifdef CONFIG_HIGHMEM
1552 .procname = "highmem_is_dirtyable",
1553 .data = &vm_highmem_is_dirtyable,
1554 .maxlen = sizeof(vm_highmem_is_dirtyable),
1556 .proc_handler = proc_dointvec_minmax,
1561 #ifdef CONFIG_MEMORY_FAILURE
1563 .procname = "memory_failure_early_kill",
1564 .data = &sysctl_memory_failure_early_kill,
1565 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1567 .proc_handler = proc_dointvec_minmax,
1572 .procname = "memory_failure_recovery",
1573 .data = &sysctl_memory_failure_recovery,
1574 .maxlen = sizeof(sysctl_memory_failure_recovery),
1576 .proc_handler = proc_dointvec_minmax,
1582 .procname = "user_reserve_kbytes",
1583 .data = &sysctl_user_reserve_kbytes,
1584 .maxlen = sizeof(sysctl_user_reserve_kbytes),
1586 .proc_handler = proc_doulongvec_minmax,
1589 .procname = "admin_reserve_kbytes",
1590 .data = &sysctl_admin_reserve_kbytes,
1591 .maxlen = sizeof(sysctl_admin_reserve_kbytes),
1593 .proc_handler = proc_doulongvec_minmax,
1595 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
1597 .procname = "mmap_rnd_bits",
1598 .data = &mmap_rnd_bits,
1599 .maxlen = sizeof(mmap_rnd_bits),
1601 .proc_handler = proc_dointvec_minmax,
1602 .extra1 = (void *)&mmap_rnd_bits_min,
1603 .extra2 = (void *)&mmap_rnd_bits_max,
1606 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
1608 .procname = "mmap_rnd_compat_bits",
1609 .data = &mmap_rnd_compat_bits,
1610 .maxlen = sizeof(mmap_rnd_compat_bits),
1612 .proc_handler = proc_dointvec_minmax,
1613 .extra1 = (void *)&mmap_rnd_compat_bits_min,
1614 .extra2 = (void *)&mmap_rnd_compat_bits_max,
1620 static struct ctl_table fs_table[] = {
1622 .procname = "inode-nr",
1623 .data = &inodes_stat,
1624 .maxlen = 2*sizeof(long),
1626 .proc_handler = proc_nr_inodes,
1629 .procname = "inode-state",
1630 .data = &inodes_stat,
1631 .maxlen = 7*sizeof(long),
1633 .proc_handler = proc_nr_inodes,
1636 .procname = "file-nr",
1637 .data = &files_stat,
1638 .maxlen = sizeof(files_stat),
1640 .proc_handler = proc_nr_files,
1643 .procname = "file-max",
1644 .data = &files_stat.max_files,
1645 .maxlen = sizeof(files_stat.max_files),
1647 .proc_handler = proc_doulongvec_minmax,
1650 .procname = "nr_open",
1651 .data = &sysctl_nr_open,
1652 .maxlen = sizeof(int),
1654 .proc_handler = proc_dointvec_minmax,
1655 .extra1 = &sysctl_nr_open_min,
1656 .extra2 = &sysctl_nr_open_max,
1659 .procname = "dentry-state",
1660 .data = &dentry_stat,
1661 .maxlen = 6*sizeof(long),
1663 .proc_handler = proc_nr_dentry,
1666 .procname = "overflowuid",
1667 .data = &fs_overflowuid,
1668 .maxlen = sizeof(int),
1670 .proc_handler = proc_dointvec_minmax,
1671 .extra1 = &minolduid,
1672 .extra2 = &maxolduid,
1675 .procname = "overflowgid",
1676 .data = &fs_overflowgid,
1677 .maxlen = sizeof(int),
1679 .proc_handler = proc_dointvec_minmax,
1680 .extra1 = &minolduid,
1681 .extra2 = &maxolduid,
1683 #ifdef CONFIG_FILE_LOCKING
1685 .procname = "leases-enable",
1686 .data = &leases_enable,
1687 .maxlen = sizeof(int),
1689 .proc_handler = proc_dointvec,
1692 #ifdef CONFIG_DNOTIFY
1694 .procname = "dir-notify-enable",
1695 .data = &dir_notify_enable,
1696 .maxlen = sizeof(int),
1698 .proc_handler = proc_dointvec,
1702 #ifdef CONFIG_FILE_LOCKING
1704 .procname = "lease-break-time",
1705 .data = &lease_break_time,
1706 .maxlen = sizeof(int),
1708 .proc_handler = proc_dointvec,
1713 .procname = "aio-nr",
1715 .maxlen = sizeof(aio_nr),
1717 .proc_handler = proc_doulongvec_minmax,
1720 .procname = "aio-max-nr",
1721 .data = &aio_max_nr,
1722 .maxlen = sizeof(aio_max_nr),
1724 .proc_handler = proc_doulongvec_minmax,
1726 #endif /* CONFIG_AIO */
1727 #ifdef CONFIG_INOTIFY_USER
1729 .procname = "inotify",
1731 .child = inotify_table,
1736 .procname = "epoll",
1738 .child = epoll_table,
1743 .procname = "protected_symlinks",
1744 .data = &sysctl_protected_symlinks,
1745 .maxlen = sizeof(int),
1747 .proc_handler = proc_dointvec_minmax,
1752 .procname = "protected_hardlinks",
1753 .data = &sysctl_protected_hardlinks,
1754 .maxlen = sizeof(int),
1756 .proc_handler = proc_dointvec_minmax,
1761 .procname = "suid_dumpable",
1762 .data = &suid_dumpable,
1763 .maxlen = sizeof(int),
1765 .proc_handler = proc_dointvec_minmax_coredump,
1769 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1771 .procname = "binfmt_misc",
1773 .child = sysctl_mount_point,
1777 .procname = "pipe-max-size",
1778 .data = &pipe_max_size,
1779 .maxlen = sizeof(int),
1781 .proc_handler = &pipe_proc_fn,
1782 .extra1 = &pipe_min_size,
1785 .procname = "pipe-user-pages-hard",
1786 .data = &pipe_user_pages_hard,
1787 .maxlen = sizeof(pipe_user_pages_hard),
1789 .proc_handler = proc_doulongvec_minmax,
1792 .procname = "pipe-user-pages-soft",
1793 .data = &pipe_user_pages_soft,
1794 .maxlen = sizeof(pipe_user_pages_soft),
1796 .proc_handler = proc_doulongvec_minmax,
1801 static struct ctl_table debug_table[] = {
1802 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1804 .procname = "exception-trace",
1805 .data = &show_unhandled_signals,
1806 .maxlen = sizeof(int),
1808 .proc_handler = proc_dointvec
1811 #if defined(CONFIG_OPTPROBES)
1813 .procname = "kprobes-optimization",
1814 .data = &sysctl_kprobes_optimization,
1815 .maxlen = sizeof(int),
1817 .proc_handler = proc_kprobes_optimization_handler,
1825 static struct ctl_table dev_table[] = {
1829 int __init sysctl_init(void)
1831 struct ctl_table_header *hdr;
1833 hdr = register_sysctl_table(sysctl_base_table);
1834 kmemleak_not_leak(hdr);
1838 #endif /* CONFIG_SYSCTL */
1844 #ifdef CONFIG_PROC_SYSCTL
1846 static int _proc_do_string(char *data, int maxlen, int write,
1847 char __user *buffer,
1848 size_t *lenp, loff_t *ppos)
1854 if (!data || !maxlen || !*lenp) {
1860 if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
1861 /* Only continue writes not past the end of buffer. */
1863 if (len > maxlen - 1)
1870 /* Start writing from beginning of buffer. */
1876 while ((p - buffer) < *lenp && len < maxlen - 1) {
1877 if (get_user(c, p++))
1879 if (c == 0 || c == '\n')
1900 if (copy_to_user(buffer, data, len))
1903 if (put_user('\n', buffer + len))
1913 static void warn_sysctl_write(struct ctl_table *table)
1915 pr_warn_once("%s wrote to %s when file position was not 0!\n"
1916 "This will not be supported in the future. To silence this\n"
1917 "warning, set kernel.sysctl_writes_strict = -1\n",
1918 current->comm, table->procname);
1922 * proc_dostring - read a string sysctl
1923 * @table: the sysctl table
1924 * @write: %TRUE if this is a write to the sysctl file
1925 * @buffer: the user buffer
1926 * @lenp: the size of the user buffer
1927 * @ppos: file position
1929 * Reads/writes a string from/to the user buffer. If the kernel
1930 * buffer provided is not large enough to hold the string, the
1931 * string is truncated. The copied string is %NULL-terminated.
1932 * If the string is being read by the user process, it is copied
1933 * and a newline '\n' is added. It is truncated if the buffer is
1936 * Returns 0 on success.
1938 int proc_dostring(struct ctl_table *table, int write,
1939 void __user *buffer, size_t *lenp, loff_t *ppos)
1941 if (write && *ppos && sysctl_writes_strict == SYSCTL_WRITES_WARN)
1942 warn_sysctl_write(table);
1944 return _proc_do_string((char *)(table->data), table->maxlen, write,
1945 (char __user *)buffer, lenp, ppos);
1948 static size_t proc_skip_spaces(char **buf)
1951 char *tmp = skip_spaces(*buf);
1957 static void proc_skip_char(char **buf, size_t *size, const char v)
1967 #define TMPBUFLEN 22
1969 * proc_get_long - reads an ASCII formatted integer from a user buffer
1971 * @buf: a kernel buffer
1972 * @size: size of the kernel buffer
1973 * @val: this is where the number will be stored
1974 * @neg: set to %TRUE if number is negative
1975 * @perm_tr: a vector which contains the allowed trailers
1976 * @perm_tr_len: size of the perm_tr vector
1977 * @tr: pointer to store the trailer character
1979 * In case of success %0 is returned and @buf and @size are updated with
1980 * the amount of bytes read. If @tr is non-NULL and a trailing
1981 * character exists (size is non-zero after returning from this
1982 * function), @tr is updated with the trailing character.
1984 static int proc_get_long(char **buf, size_t *size,
1985 unsigned long *val, bool *neg,
1986 const char *perm_tr, unsigned perm_tr_len, char *tr)
1989 char *p, tmp[TMPBUFLEN];
1995 if (len > TMPBUFLEN - 1)
1996 len = TMPBUFLEN - 1;
1998 memcpy(tmp, *buf, len);
2002 if (*p == '-' && *size > 1) {
2010 *val = simple_strtoul(p, &p, 0);
2014 /* We don't know if the next char is whitespace thus we may accept
2015 * invalid integers (e.g. 1234...a) or two integers instead of one
2016 * (e.g. 123...1). So lets not allow such large numbers. */
2017 if (len == TMPBUFLEN - 1)
2020 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2023 if (tr && (len < *size))
2033 * proc_put_long - converts an integer to a decimal ASCII formatted string
2035 * @buf: the user buffer
2036 * @size: the size of the user buffer
2037 * @val: the integer to be converted
2038 * @neg: sign of the number, %TRUE for negative
2040 * In case of success %0 is returned and @buf and @size are updated with
2041 * the amount of bytes written.
2043 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2047 char tmp[TMPBUFLEN], *p = tmp;
2049 sprintf(p, "%s%lu", neg ? "-" : "", val);
2053 if (copy_to_user(*buf, tmp, len))
2061 static int proc_put_char(void __user **buf, size_t *size, char c)
2064 char __user **buffer = (char __user **)buf;
2065 if (put_user(c, *buffer))
2067 (*size)--, (*buffer)++;
2073 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2075 int write, void *data)
2079 if (*lvalp > (unsigned long) INT_MAX + 1)
2083 if (*lvalp > (unsigned long) INT_MAX)
2091 *lvalp = -(unsigned long)val;
2094 *lvalp = (unsigned long)val;
2100 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2102 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2103 int write, void __user *buffer,
2104 size_t *lenp, loff_t *ppos,
2105 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2106 int write, void *data),
2109 int *i, vleft, first = 1, err = 0;
2110 unsigned long page = 0;
2114 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2119 i = (int *) tbl_data;
2120 vleft = table->maxlen / sizeof(*i);
2124 conv = do_proc_dointvec_conv;
2128 switch (sysctl_writes_strict) {
2129 case SYSCTL_WRITES_STRICT:
2131 case SYSCTL_WRITES_WARN:
2132 warn_sysctl_write(table);
2139 if (left > PAGE_SIZE - 1)
2140 left = PAGE_SIZE - 1;
2141 page = __get_free_page(GFP_TEMPORARY);
2142 kbuf = (char *) page;
2145 if (copy_from_user(kbuf, buffer, left)) {
2152 for (; left && vleft--; i++, first=0) {
2157 left -= proc_skip_spaces(&kbuf);
2161 err = proc_get_long(&kbuf, &left, &lval, &neg,
2163 sizeof(proc_wspace_sep), NULL);
2166 if (conv(&neg, &lval, i, 1, data)) {
2171 if (conv(&neg, &lval, i, 0, data)) {
2176 err = proc_put_char(&buffer, &left, '\t');
2179 err = proc_put_long(&buffer, &left, lval, neg);
2185 if (!write && !first && left && !err)
2186 err = proc_put_char(&buffer, &left, '\n');
2187 if (write && !err && left)
2188 left -= proc_skip_spaces(&kbuf);
2193 return err ? : -EINVAL;
2201 static int do_proc_dointvec(struct ctl_table *table, int write,
2202 void __user *buffer, size_t *lenp, loff_t *ppos,
2203 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2204 int write, void *data),
2207 return __do_proc_dointvec(table->data, table, write,
2208 buffer, lenp, ppos, conv, data);
2212 * proc_dointvec - read a vector of integers
2213 * @table: the sysctl table
2214 * @write: %TRUE if this is a write to the sysctl file
2215 * @buffer: the user buffer
2216 * @lenp: the size of the user buffer
2217 * @ppos: file position
2219 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2220 * values from/to the user buffer, treated as an ASCII string.
2222 * Returns 0 on success.
2224 int proc_dointvec(struct ctl_table *table, int write,
2225 void __user *buffer, size_t *lenp, loff_t *ppos)
2227 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2232 * Taint values can only be increased
2233 * This means we can safely use a temporary.
2235 static int proc_taint(struct ctl_table *table, int write,
2236 void __user *buffer, size_t *lenp, loff_t *ppos)
2239 unsigned long tmptaint = get_taint();
2242 if (write && !capable(CAP_SYS_ADMIN))
2247 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2253 * Poor man's atomic or. Not worth adding a primitive
2254 * to everyone's atomic.h for this
2257 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2258 if ((tmptaint >> i) & 1)
2259 add_taint(i, LOCKDEP_STILL_OK);
2266 #ifdef CONFIG_PRINTK
2267 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2268 void __user *buffer, size_t *lenp, loff_t *ppos)
2270 if (write && !capable(CAP_SYS_ADMIN))
2273 return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2277 struct do_proc_dointvec_minmax_conv_param {
2282 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2284 int write, void *data)
2286 struct do_proc_dointvec_minmax_conv_param *param = data;
2288 int val = *negp ? -*lvalp : *lvalp;
2289 if ((param->min && *param->min > val) ||
2290 (param->max && *param->max < val))
2297 *lvalp = -(unsigned long)val;
2300 *lvalp = (unsigned long)val;
2307 * proc_dointvec_minmax - read a vector of integers with min/max values
2308 * @table: the sysctl table
2309 * @write: %TRUE if this is a write to the sysctl file
2310 * @buffer: the user buffer
2311 * @lenp: the size of the user buffer
2312 * @ppos: file position
2314 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2315 * values from/to the user buffer, treated as an ASCII string.
2317 * This routine will ensure the values are within the range specified by
2318 * table->extra1 (min) and table->extra2 (max).
2320 * Returns 0 on success.
2322 int proc_dointvec_minmax(struct ctl_table *table, int write,
2323 void __user *buffer, size_t *lenp, loff_t *ppos)
2325 struct do_proc_dointvec_minmax_conv_param param = {
2326 .min = (int *) table->extra1,
2327 .max = (int *) table->extra2,
2329 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2330 do_proc_dointvec_minmax_conv, ¶m);
2333 static void validate_coredump_safety(void)
2335 #ifdef CONFIG_COREDUMP
2336 if (suid_dumpable == SUID_DUMP_ROOT &&
2337 core_pattern[0] != '/' && core_pattern[0] != '|') {
2338 printk(KERN_WARNING "Unsafe core_pattern used with "\
2339 "suid_dumpable=2. Pipe handler or fully qualified "\
2340 "core dump path required.\n");
2345 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2346 void __user *buffer, size_t *lenp, loff_t *ppos)
2348 int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2350 validate_coredump_safety();
2354 #ifdef CONFIG_COREDUMP
2355 static int proc_dostring_coredump(struct ctl_table *table, int write,
2356 void __user *buffer, size_t *lenp, loff_t *ppos)
2358 int error = proc_dostring(table, write, buffer, lenp, ppos);
2360 validate_coredump_safety();
2365 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2366 void __user *buffer,
2367 size_t *lenp, loff_t *ppos,
2368 unsigned long convmul,
2369 unsigned long convdiv)
2371 unsigned long *i, *min, *max;
2372 int vleft, first = 1, err = 0;
2373 unsigned long page = 0;
2377 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2382 i = (unsigned long *) data;
2383 min = (unsigned long *) table->extra1;
2384 max = (unsigned long *) table->extra2;
2385 vleft = table->maxlen / sizeof(unsigned long);
2390 switch (sysctl_writes_strict) {
2391 case SYSCTL_WRITES_STRICT:
2393 case SYSCTL_WRITES_WARN:
2394 warn_sysctl_write(table);
2401 if (left > PAGE_SIZE - 1)
2402 left = PAGE_SIZE - 1;
2403 page = __get_free_page(GFP_TEMPORARY);
2404 kbuf = (char *) page;
2407 if (copy_from_user(kbuf, buffer, left)) {
2414 for (; left && vleft--; i++, first = 0) {
2420 left -= proc_skip_spaces(&kbuf);
2422 err = proc_get_long(&kbuf, &left, &val, &neg,
2424 sizeof(proc_wspace_sep), NULL);
2429 if ((min && val < *min) || (max && val > *max))
2433 val = convdiv * (*i) / convmul;
2435 err = proc_put_char(&buffer, &left, '\t');
2439 err = proc_put_long(&buffer, &left, val, false);
2445 if (!write && !first && left && !err)
2446 err = proc_put_char(&buffer, &left, '\n');
2448 left -= proc_skip_spaces(&kbuf);
2453 return err ? : -EINVAL;
2461 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2462 void __user *buffer,
2463 size_t *lenp, loff_t *ppos,
2464 unsigned long convmul,
2465 unsigned long convdiv)
2467 return __do_proc_doulongvec_minmax(table->data, table, write,
2468 buffer, lenp, ppos, convmul, convdiv);
2472 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2473 * @table: the sysctl table
2474 * @write: %TRUE if this is a write to the sysctl file
2475 * @buffer: the user buffer
2476 * @lenp: the size of the user buffer
2477 * @ppos: file position
2479 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2480 * values from/to the user buffer, treated as an ASCII string.
2482 * This routine will ensure the values are within the range specified by
2483 * table->extra1 (min) and table->extra2 (max).
2485 * Returns 0 on success.
2487 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2488 void __user *buffer, size_t *lenp, loff_t *ppos)
2490 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2494 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2495 * @table: the sysctl table
2496 * @write: %TRUE if this is a write to the sysctl file
2497 * @buffer: the user buffer
2498 * @lenp: the size of the user buffer
2499 * @ppos: file position
2501 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2502 * values from/to the user buffer, treated as an ASCII string. The values
2503 * are treated as milliseconds, and converted to jiffies when they are stored.
2505 * This routine will ensure the values are within the range specified by
2506 * table->extra1 (min) and table->extra2 (max).
2508 * Returns 0 on success.
2510 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2511 void __user *buffer,
2512 size_t *lenp, loff_t *ppos)
2514 return do_proc_doulongvec_minmax(table, write, buffer,
2515 lenp, ppos, HZ, 1000l);
2519 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2521 int write, void *data)
2524 if (*lvalp > LONG_MAX / HZ)
2526 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2532 lval = -(unsigned long)val;
2535 lval = (unsigned long)val;
2542 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2544 int write, void *data)
2547 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2549 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2555 lval = -(unsigned long)val;
2558 lval = (unsigned long)val;
2560 *lvalp = jiffies_to_clock_t(lval);
2565 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2567 int write, void *data)
2570 unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2580 lval = -(unsigned long)val;
2583 lval = (unsigned long)val;
2585 *lvalp = jiffies_to_msecs(lval);
2591 * proc_dointvec_jiffies - read a vector of integers as seconds
2592 * @table: the sysctl table
2593 * @write: %TRUE if this is a write to the sysctl file
2594 * @buffer: the user buffer
2595 * @lenp: the size of the user buffer
2596 * @ppos: file position
2598 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2599 * values from/to the user buffer, treated as an ASCII string.
2600 * The values read are assumed to be in seconds, and are converted into
2603 * Returns 0 on success.
2605 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2606 void __user *buffer, size_t *lenp, loff_t *ppos)
2608 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2609 do_proc_dointvec_jiffies_conv,NULL);
2613 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2614 * @table: the sysctl table
2615 * @write: %TRUE if this is a write to the sysctl file
2616 * @buffer: the user buffer
2617 * @lenp: the size of the user buffer
2618 * @ppos: pointer to the file position
2620 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2621 * values from/to the user buffer, treated as an ASCII string.
2622 * The values read are assumed to be in 1/USER_HZ seconds, and
2623 * are converted into jiffies.
2625 * Returns 0 on success.
2627 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2628 void __user *buffer, size_t *lenp, loff_t *ppos)
2630 return do_proc_dointvec(table,write,buffer,lenp,ppos,
2631 do_proc_dointvec_userhz_jiffies_conv,NULL);
2635 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2636 * @table: the sysctl table
2637 * @write: %TRUE if this is a write to the sysctl file
2638 * @buffer: the user buffer
2639 * @lenp: the size of the user buffer
2640 * @ppos: file position
2641 * @ppos: the current position in the file
2643 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2644 * values from/to the user buffer, treated as an ASCII string.
2645 * The values read are assumed to be in 1/1000 seconds, and
2646 * are converted into jiffies.
2648 * Returns 0 on success.
2650 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2651 void __user *buffer, size_t *lenp, loff_t *ppos)
2653 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2654 do_proc_dointvec_ms_jiffies_conv, NULL);
2657 static int proc_do_cad_pid(struct ctl_table *table, int write,
2658 void __user *buffer, size_t *lenp, loff_t *ppos)
2660 struct pid *new_pid;
2664 tmp = pid_vnr(cad_pid);
2666 r = __do_proc_dointvec(&tmp, table, write, buffer,
2667 lenp, ppos, NULL, NULL);
2671 new_pid = find_get_pid(tmp);
2675 put_pid(xchg(&cad_pid, new_pid));
2680 * proc_do_large_bitmap - read/write from/to a large bitmap
2681 * @table: the sysctl table
2682 * @write: %TRUE if this is a write to the sysctl file
2683 * @buffer: the user buffer
2684 * @lenp: the size of the user buffer
2685 * @ppos: file position
2687 * The bitmap is stored at table->data and the bitmap length (in bits)
2690 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2691 * large bitmaps may be represented in a compact manner. Writing into
2692 * the file will clear the bitmap then update it with the given input.
2694 * Returns 0 on success.
2696 int proc_do_large_bitmap(struct ctl_table *table, int write,
2697 void __user *buffer, size_t *lenp, loff_t *ppos)
2701 size_t left = *lenp;
2702 unsigned long bitmap_len = table->maxlen;
2703 unsigned long *bitmap = *(unsigned long **) table->data;
2704 unsigned long *tmp_bitmap = NULL;
2705 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2707 if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
2713 unsigned long page = 0;
2716 if (left > PAGE_SIZE - 1)
2717 left = PAGE_SIZE - 1;
2719 page = __get_free_page(GFP_TEMPORARY);
2720 kbuf = (char *) page;
2723 if (copy_from_user(kbuf, buffer, left)) {
2729 tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2735 proc_skip_char(&kbuf, &left, '\n');
2736 while (!err && left) {
2737 unsigned long val_a, val_b;
2740 err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2744 if (val_a >= bitmap_len || neg) {
2756 err = proc_get_long(&kbuf, &left, &val_b,
2757 &neg, tr_b, sizeof(tr_b),
2761 if (val_b >= bitmap_len || neg ||
2772 bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
2774 proc_skip_char(&kbuf, &left, '\n');
2778 unsigned long bit_a, bit_b = 0;
2781 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2782 if (bit_a >= bitmap_len)
2784 bit_b = find_next_zero_bit(bitmap, bitmap_len,
2788 err = proc_put_char(&buffer, &left, ',');
2792 err = proc_put_long(&buffer, &left, bit_a, false);
2795 if (bit_a != bit_b) {
2796 err = proc_put_char(&buffer, &left, '-');
2799 err = proc_put_long(&buffer, &left, bit_b, false);
2807 err = proc_put_char(&buffer, &left, '\n');
2813 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2815 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
2827 #else /* CONFIG_PROC_SYSCTL */
2829 int proc_dostring(struct ctl_table *table, int write,
2830 void __user *buffer, size_t *lenp, loff_t *ppos)
2835 int proc_dointvec(struct ctl_table *table, int write,
2836 void __user *buffer, size_t *lenp, loff_t *ppos)
2841 int proc_dointvec_minmax(struct ctl_table *table, int write,
2842 void __user *buffer, size_t *lenp, loff_t *ppos)
2847 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2848 void __user *buffer, size_t *lenp, loff_t *ppos)
2853 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2854 void __user *buffer, size_t *lenp, loff_t *ppos)
2859 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2860 void __user *buffer, size_t *lenp, loff_t *ppos)
2865 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2866 void __user *buffer, size_t *lenp, loff_t *ppos)
2871 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2872 void __user *buffer,
2873 size_t *lenp, loff_t *ppos)
2879 #endif /* CONFIG_PROC_SYSCTL */
2882 * No sense putting this after each symbol definition, twice,
2883 * exception granted :-)
2885 EXPORT_SYMBOL(proc_dointvec);
2886 EXPORT_SYMBOL(proc_dointvec_jiffies);
2887 EXPORT_SYMBOL(proc_dointvec_minmax);
2888 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2889 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2890 EXPORT_SYMBOL(proc_dostring);
2891 EXPORT_SYMBOL(proc_doulongvec_minmax);
2892 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);