1 // SPDX-License-Identifier: GPL-2.0-only
3 * sysctl.c: General linux system control interface
5 * Begun 24 March 1995, Stephen Tweedie
6 * Added /proc support, Dec 1995
7 * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
8 * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
9 * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
10 * Dynamic registration fixes, Stephen Tweedie.
11 * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
12 * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
14 * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
15 * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
16 * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
18 * The list_for_each() macro wasn't appropriate for the sysctl loop.
19 * Removed it and replaced it with older style, 03/23/00, Bill Wendling
22 #include <linux/module.h>
23 #include <linux/aio.h>
25 #include <linux/swap.h>
26 #include <linux/slab.h>
27 #include <linux/sysctl.h>
28 #include <linux/bitmap.h>
29 #include <linux/signal.h>
30 #include <linux/printk.h>
31 #include <linux/proc_fs.h>
32 #include <linux/security.h>
33 #include <linux/ctype.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/sched/coredump.h>
67 #include <linux/kexec.h>
68 #include <linux/bpf.h>
69 #include <linux/mount.h>
70 #include <linux/userfaultfd_k.h>
72 #include "../lib/kstrtox.h"
74 #include <linux/uaccess.h>
75 #include <asm/processor.h>
79 #include <asm/stacktrace.h>
83 #include <asm/setup.h>
85 #ifdef CONFIG_BSD_PROCESS_ACCT
86 #include <linux/acct.h>
88 #ifdef CONFIG_RT_MUTEXES
89 #include <linux/rtmutex.h>
91 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
92 #include <linux/lockdep.h>
94 #ifdef CONFIG_CHR_DEV_SG
97 #ifdef CONFIG_STACKLEAK_RUNTIME_DISABLE
98 #include <linux/stackleak.h>
100 #ifdef CONFIG_LOCKUP_DETECTOR
101 #include <linux/nmi.h>
104 #if defined(CONFIG_SYSCTL)
106 /* External variables not in a header file. */
107 extern int suid_dumpable;
108 #ifdef CONFIG_COREDUMP
109 extern int core_uses_pid;
110 extern char core_pattern[];
111 extern unsigned int core_pipe_limit;
114 extern int pid_max_min, pid_max_max;
115 extern int percpu_pagelist_fraction;
116 extern int latencytop_enabled;
117 extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
119 extern int sysctl_nr_trim_pages;
122 /* Constants used for minimum and maximum */
123 #ifdef CONFIG_LOCKUP_DETECTOR
124 static int sixty = 60;
127 static int __maybe_unused neg_one = -1;
128 static int __maybe_unused two = 2;
129 static int __maybe_unused four = 4;
130 static unsigned long zero_ul;
131 static unsigned long one_ul = 1;
132 static unsigned long long_max = LONG_MAX;
133 static int one_hundred = 100;
134 static int one_thousand = 1000;
136 static int ten_thousand = 10000;
138 #ifdef CONFIG_PERF_EVENTS
139 static int six_hundred_forty_kb = 640 * 1024;
142 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
143 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
145 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
146 static int maxolduid = 65535;
147 static int minolduid;
149 static int ngroups_max = NGROUPS_MAX;
150 static const int cap_last_cap = CAP_LAST_CAP;
153 * This is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs
154 * and hung_task_check_interval_secs
156 #ifdef CONFIG_DETECT_HUNG_TASK
157 static unsigned long hung_task_timeout_max = (LONG_MAX/HZ);
160 #ifdef CONFIG_INOTIFY_USER
161 #include <linux/inotify.h>
167 extern int pwrsw_enabled;
170 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
171 extern int unaligned_enabled;
175 extern int unaligned_dump_stack;
178 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
179 extern int no_unaligned_warning;
182 #ifdef CONFIG_PROC_SYSCTL
185 * enum sysctl_writes_mode - supported sysctl write modes
187 * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
188 * to be written, and multiple writes on the same sysctl file descriptor
189 * will rewrite the sysctl value, regardless of file position. No warning
190 * is issued when the initial position is not 0.
191 * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
193 * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
194 * file position 0 and the value must be fully contained in the buffer
195 * sent to the write syscall. If dealing with strings respect the file
196 * position, but restrict this to the max length of the buffer, anything
197 * passed the max length will be ignored. Multiple writes will append
200 * These write modes control how current file position affects the behavior of
201 * updating sysctl values through the proc interface on each write.
203 enum sysctl_writes_mode {
204 SYSCTL_WRITES_LEGACY = -1,
205 SYSCTL_WRITES_WARN = 0,
206 SYSCTL_WRITES_STRICT = 1,
209 static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
211 static int proc_do_cad_pid(struct ctl_table *table, int write,
212 void __user *buffer, size_t *lenp, loff_t *ppos);
213 static int proc_taint(struct ctl_table *table, int write,
214 void __user *buffer, size_t *lenp, loff_t *ppos);
218 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
219 void __user *buffer, size_t *lenp, loff_t *ppos);
222 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
223 void __user *buffer, size_t *lenp, loff_t *ppos);
224 #ifdef CONFIG_COREDUMP
225 static int proc_dostring_coredump(struct ctl_table *table, int write,
226 void __user *buffer, size_t *lenp, loff_t *ppos);
228 static int proc_dopipe_max_size(struct ctl_table *table, int write,
229 void __user *buffer, size_t *lenp, loff_t *ppos);
231 #ifdef CONFIG_MAGIC_SYSRQ
232 /* Note: sysrq code uses its own private copy */
233 static int __sysrq_enabled = CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE;
235 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
236 void __user *buffer, size_t *lenp,
241 error = proc_dointvec(table, write, buffer, lenp, ppos);
246 sysrq_toggle_support(__sysrq_enabled);
253 static struct ctl_table kern_table[];
254 static struct ctl_table vm_table[];
255 static struct ctl_table fs_table[];
256 static struct ctl_table debug_table[];
257 static struct ctl_table dev_table[];
258 extern struct ctl_table random_table[];
260 extern struct ctl_table epoll_table[];
263 #ifdef CONFIG_FW_LOADER_USER_HELPER
264 extern struct ctl_table firmware_config_table[];
267 #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
268 defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
269 int sysctl_legacy_va_layout;
272 /* The default sysctl tables: */
274 static struct ctl_table sysctl_base_table[] = {
276 .procname = "kernel",
293 .child = debug_table,
303 #ifdef CONFIG_SCHED_DEBUG
304 static int min_sched_granularity_ns = 100000; /* 100 usecs */
305 static int max_sched_granularity_ns = NSEC_PER_SEC; /* 1 second */
306 static int min_wakeup_granularity_ns; /* 0 usecs */
307 static int max_wakeup_granularity_ns = NSEC_PER_SEC; /* 1 second */
309 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
310 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
311 #endif /* CONFIG_SMP */
312 #endif /* CONFIG_SCHED_DEBUG */
314 #ifdef CONFIG_COMPACTION
315 static int min_extfrag_threshold;
316 static int max_extfrag_threshold = 1000;
319 static struct ctl_table kern_table[] = {
321 .procname = "sched_child_runs_first",
322 .data = &sysctl_sched_child_runs_first,
323 .maxlen = sizeof(unsigned int),
325 .proc_handler = proc_dointvec,
327 #ifdef CONFIG_SCHED_DEBUG
329 .procname = "sched_min_granularity_ns",
330 .data = &sysctl_sched_min_granularity,
331 .maxlen = sizeof(unsigned int),
333 .proc_handler = sched_proc_update_handler,
334 .extra1 = &min_sched_granularity_ns,
335 .extra2 = &max_sched_granularity_ns,
338 .procname = "sched_latency_ns",
339 .data = &sysctl_sched_latency,
340 .maxlen = sizeof(unsigned int),
342 .proc_handler = sched_proc_update_handler,
343 .extra1 = &min_sched_granularity_ns,
344 .extra2 = &max_sched_granularity_ns,
347 .procname = "sched_wakeup_granularity_ns",
348 .data = &sysctl_sched_wakeup_granularity,
349 .maxlen = sizeof(unsigned int),
351 .proc_handler = sched_proc_update_handler,
352 .extra1 = &min_wakeup_granularity_ns,
353 .extra2 = &max_wakeup_granularity_ns,
357 .procname = "sched_tunable_scaling",
358 .data = &sysctl_sched_tunable_scaling,
359 .maxlen = sizeof(enum sched_tunable_scaling),
361 .proc_handler = sched_proc_update_handler,
362 .extra1 = &min_sched_tunable_scaling,
363 .extra2 = &max_sched_tunable_scaling,
366 .procname = "sched_migration_cost_ns",
367 .data = &sysctl_sched_migration_cost,
368 .maxlen = sizeof(unsigned int),
370 .proc_handler = proc_dointvec,
373 .procname = "sched_nr_migrate",
374 .data = &sysctl_sched_nr_migrate,
375 .maxlen = sizeof(unsigned int),
377 .proc_handler = proc_dointvec,
379 #ifdef CONFIG_SCHEDSTATS
381 .procname = "sched_schedstats",
383 .maxlen = sizeof(unsigned int),
385 .proc_handler = sysctl_schedstats,
386 .extra1 = SYSCTL_ZERO,
387 .extra2 = SYSCTL_ONE,
389 #endif /* CONFIG_SCHEDSTATS */
390 #endif /* CONFIG_SMP */
391 #ifdef CONFIG_NUMA_BALANCING
393 .procname = "numa_balancing_scan_delay_ms",
394 .data = &sysctl_numa_balancing_scan_delay,
395 .maxlen = sizeof(unsigned int),
397 .proc_handler = proc_dointvec,
400 .procname = "numa_balancing_scan_period_min_ms",
401 .data = &sysctl_numa_balancing_scan_period_min,
402 .maxlen = sizeof(unsigned int),
404 .proc_handler = proc_dointvec,
407 .procname = "numa_balancing_scan_period_max_ms",
408 .data = &sysctl_numa_balancing_scan_period_max,
409 .maxlen = sizeof(unsigned int),
411 .proc_handler = proc_dointvec,
414 .procname = "numa_balancing_scan_size_mb",
415 .data = &sysctl_numa_balancing_scan_size,
416 .maxlen = sizeof(unsigned int),
418 .proc_handler = proc_dointvec_minmax,
419 .extra1 = SYSCTL_ONE,
422 .procname = "numa_balancing",
423 .data = NULL, /* filled in by handler */
424 .maxlen = sizeof(unsigned int),
426 .proc_handler = sysctl_numa_balancing,
427 .extra1 = SYSCTL_ZERO,
428 .extra2 = SYSCTL_ONE,
430 #endif /* CONFIG_NUMA_BALANCING */
431 #endif /* CONFIG_SCHED_DEBUG */
433 .procname = "sched_rt_period_us",
434 .data = &sysctl_sched_rt_period,
435 .maxlen = sizeof(unsigned int),
437 .proc_handler = sched_rt_handler,
440 .procname = "sched_rt_runtime_us",
441 .data = &sysctl_sched_rt_runtime,
442 .maxlen = sizeof(int),
444 .proc_handler = sched_rt_handler,
447 .procname = "sched_rr_timeslice_ms",
448 .data = &sysctl_sched_rr_timeslice,
449 .maxlen = sizeof(int),
451 .proc_handler = sched_rr_handler,
453 #ifdef CONFIG_UCLAMP_TASK
455 .procname = "sched_util_clamp_min",
456 .data = &sysctl_sched_uclamp_util_min,
457 .maxlen = sizeof(unsigned int),
459 .proc_handler = sysctl_sched_uclamp_handler,
462 .procname = "sched_util_clamp_max",
463 .data = &sysctl_sched_uclamp_util_max,
464 .maxlen = sizeof(unsigned int),
466 .proc_handler = sysctl_sched_uclamp_handler,
469 #ifdef CONFIG_SCHED_AUTOGROUP
471 .procname = "sched_autogroup_enabled",
472 .data = &sysctl_sched_autogroup_enabled,
473 .maxlen = sizeof(unsigned int),
475 .proc_handler = proc_dointvec_minmax,
476 .extra1 = SYSCTL_ZERO,
477 .extra2 = SYSCTL_ONE,
480 #ifdef CONFIG_CFS_BANDWIDTH
482 .procname = "sched_cfs_bandwidth_slice_us",
483 .data = &sysctl_sched_cfs_bandwidth_slice,
484 .maxlen = sizeof(unsigned int),
486 .proc_handler = proc_dointvec_minmax,
487 .extra1 = SYSCTL_ONE,
490 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
492 .procname = "sched_energy_aware",
493 .data = &sysctl_sched_energy_aware,
494 .maxlen = sizeof(unsigned int),
496 .proc_handler = sched_energy_aware_handler,
497 .extra1 = SYSCTL_ZERO,
498 .extra2 = SYSCTL_ONE,
501 #ifdef CONFIG_PROVE_LOCKING
503 .procname = "prove_locking",
504 .data = &prove_locking,
505 .maxlen = sizeof(int),
507 .proc_handler = proc_dointvec,
510 #ifdef CONFIG_LOCK_STAT
512 .procname = "lock_stat",
514 .maxlen = sizeof(int),
516 .proc_handler = proc_dointvec,
521 .data = &panic_timeout,
522 .maxlen = sizeof(int),
524 .proc_handler = proc_dointvec,
526 #ifdef CONFIG_COREDUMP
528 .procname = "core_uses_pid",
529 .data = &core_uses_pid,
530 .maxlen = sizeof(int),
532 .proc_handler = proc_dointvec,
535 .procname = "core_pattern",
536 .data = core_pattern,
537 .maxlen = CORENAME_MAX_SIZE,
539 .proc_handler = proc_dostring_coredump,
542 .procname = "core_pipe_limit",
543 .data = &core_pipe_limit,
544 .maxlen = sizeof(unsigned int),
546 .proc_handler = proc_dointvec,
549 #ifdef CONFIG_PROC_SYSCTL
551 .procname = "tainted",
552 .maxlen = sizeof(long),
554 .proc_handler = proc_taint,
557 .procname = "sysctl_writes_strict",
558 .data = &sysctl_writes_strict,
559 .maxlen = sizeof(int),
561 .proc_handler = proc_dointvec_minmax,
563 .extra2 = SYSCTL_ONE,
566 #ifdef CONFIG_LATENCYTOP
568 .procname = "latencytop",
569 .data = &latencytop_enabled,
570 .maxlen = sizeof(int),
572 .proc_handler = sysctl_latencytop,
575 #ifdef CONFIG_BLK_DEV_INITRD
577 .procname = "real-root-dev",
578 .data = &real_root_dev,
579 .maxlen = sizeof(int),
581 .proc_handler = proc_dointvec,
585 .procname = "print-fatal-signals",
586 .data = &print_fatal_signals,
587 .maxlen = sizeof(int),
589 .proc_handler = proc_dointvec,
593 .procname = "reboot-cmd",
594 .data = reboot_command,
597 .proc_handler = proc_dostring,
600 .procname = "stop-a",
601 .data = &stop_a_enabled,
602 .maxlen = sizeof (int),
604 .proc_handler = proc_dointvec,
607 .procname = "scons-poweroff",
608 .data = &scons_pwroff,
609 .maxlen = sizeof (int),
611 .proc_handler = proc_dointvec,
614 #ifdef CONFIG_SPARC64
616 .procname = "tsb-ratio",
617 .data = &sysctl_tsb_ratio,
618 .maxlen = sizeof (int),
620 .proc_handler = proc_dointvec,
625 .procname = "soft-power",
626 .data = &pwrsw_enabled,
627 .maxlen = sizeof (int),
629 .proc_handler = proc_dointvec,
632 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
634 .procname = "unaligned-trap",
635 .data = &unaligned_enabled,
636 .maxlen = sizeof (int),
638 .proc_handler = proc_dointvec,
642 .procname = "ctrl-alt-del",
644 .maxlen = sizeof(int),
646 .proc_handler = proc_dointvec,
648 #ifdef CONFIG_FUNCTION_TRACER
650 .procname = "ftrace_enabled",
651 .data = &ftrace_enabled,
652 .maxlen = sizeof(int),
654 .proc_handler = ftrace_enable_sysctl,
657 #ifdef CONFIG_STACK_TRACER
659 .procname = "stack_tracer_enabled",
660 .data = &stack_tracer_enabled,
661 .maxlen = sizeof(int),
663 .proc_handler = stack_trace_sysctl,
666 #ifdef CONFIG_TRACING
668 .procname = "ftrace_dump_on_oops",
669 .data = &ftrace_dump_on_oops,
670 .maxlen = sizeof(int),
672 .proc_handler = proc_dointvec,
675 .procname = "traceoff_on_warning",
676 .data = &__disable_trace_on_warning,
677 .maxlen = sizeof(__disable_trace_on_warning),
679 .proc_handler = proc_dointvec,
682 .procname = "tracepoint_printk",
683 .data = &tracepoint_printk,
684 .maxlen = sizeof(tracepoint_printk),
686 .proc_handler = tracepoint_printk_sysctl,
689 #ifdef CONFIG_KEXEC_CORE
691 .procname = "kexec_load_disabled",
692 .data = &kexec_load_disabled,
693 .maxlen = sizeof(int),
695 /* only handle a transition from default "0" to "1" */
696 .proc_handler = proc_dointvec_minmax,
697 .extra1 = SYSCTL_ONE,
698 .extra2 = SYSCTL_ONE,
701 #ifdef CONFIG_MODULES
703 .procname = "modprobe",
704 .data = &modprobe_path,
705 .maxlen = KMOD_PATH_LEN,
707 .proc_handler = proc_dostring,
710 .procname = "modules_disabled",
711 .data = &modules_disabled,
712 .maxlen = sizeof(int),
714 /* only handle a transition from default "0" to "1" */
715 .proc_handler = proc_dointvec_minmax,
716 .extra1 = SYSCTL_ONE,
717 .extra2 = SYSCTL_ONE,
720 #ifdef CONFIG_UEVENT_HELPER
722 .procname = "hotplug",
723 .data = &uevent_helper,
724 .maxlen = UEVENT_HELPER_PATH_LEN,
726 .proc_handler = proc_dostring,
729 #ifdef CONFIG_CHR_DEV_SG
731 .procname = "sg-big-buff",
732 .data = &sg_big_buff,
733 .maxlen = sizeof (int),
735 .proc_handler = proc_dointvec,
738 #ifdef CONFIG_BSD_PROCESS_ACCT
742 .maxlen = 3*sizeof(int),
744 .proc_handler = proc_dointvec,
747 #ifdef CONFIG_MAGIC_SYSRQ
750 .data = &__sysrq_enabled,
751 .maxlen = sizeof (int),
753 .proc_handler = sysrq_sysctl_handler,
756 #ifdef CONFIG_PROC_SYSCTL
758 .procname = "cad_pid",
760 .maxlen = sizeof (int),
762 .proc_handler = proc_do_cad_pid,
766 .procname = "threads-max",
768 .maxlen = sizeof(int),
770 .proc_handler = sysctl_max_threads,
773 .procname = "random",
775 .child = random_table,
778 .procname = "usermodehelper",
780 .child = usermodehelper_table,
782 #ifdef CONFIG_FW_LOADER_USER_HELPER
784 .procname = "firmware_config",
786 .child = firmware_config_table,
790 .procname = "overflowuid",
791 .data = &overflowuid,
792 .maxlen = sizeof(int),
794 .proc_handler = proc_dointvec_minmax,
795 .extra1 = &minolduid,
796 .extra2 = &maxolduid,
799 .procname = "overflowgid",
800 .data = &overflowgid,
801 .maxlen = sizeof(int),
803 .proc_handler = proc_dointvec_minmax,
804 .extra1 = &minolduid,
805 .extra2 = &maxolduid,
808 #ifdef CONFIG_MATHEMU
810 .procname = "ieee_emulation_warnings",
811 .data = &sysctl_ieee_emulation_warnings,
812 .maxlen = sizeof(int),
814 .proc_handler = proc_dointvec,
818 .procname = "userprocess_debug",
819 .data = &show_unhandled_signals,
820 .maxlen = sizeof(int),
822 .proc_handler = proc_dointvec,
826 .procname = "pid_max",
828 .maxlen = sizeof (int),
830 .proc_handler = proc_dointvec_minmax,
831 .extra1 = &pid_max_min,
832 .extra2 = &pid_max_max,
835 .procname = "panic_on_oops",
836 .data = &panic_on_oops,
837 .maxlen = sizeof(int),
839 .proc_handler = proc_dointvec,
842 .procname = "panic_print",
843 .data = &panic_print,
844 .maxlen = sizeof(unsigned long),
846 .proc_handler = proc_doulongvec_minmax,
848 #if defined CONFIG_PRINTK
850 .procname = "printk",
851 .data = &console_loglevel,
852 .maxlen = 4*sizeof(int),
854 .proc_handler = proc_dointvec,
857 .procname = "printk_ratelimit",
858 .data = &printk_ratelimit_state.interval,
859 .maxlen = sizeof(int),
861 .proc_handler = proc_dointvec_jiffies,
864 .procname = "printk_ratelimit_burst",
865 .data = &printk_ratelimit_state.burst,
866 .maxlen = sizeof(int),
868 .proc_handler = proc_dointvec,
871 .procname = "printk_delay",
872 .data = &printk_delay_msec,
873 .maxlen = sizeof(int),
875 .proc_handler = proc_dointvec_minmax,
876 .extra1 = SYSCTL_ZERO,
877 .extra2 = &ten_thousand,
880 .procname = "printk_devkmsg",
881 .data = devkmsg_log_str,
882 .maxlen = DEVKMSG_STR_MAX_SIZE,
884 .proc_handler = devkmsg_sysctl_set_loglvl,
887 .procname = "dmesg_restrict",
888 .data = &dmesg_restrict,
889 .maxlen = sizeof(int),
891 .proc_handler = proc_dointvec_minmax_sysadmin,
892 .extra1 = SYSCTL_ZERO,
893 .extra2 = SYSCTL_ONE,
896 .procname = "kptr_restrict",
897 .data = &kptr_restrict,
898 .maxlen = sizeof(int),
900 .proc_handler = proc_dointvec_minmax_sysadmin,
901 .extra1 = SYSCTL_ZERO,
906 .procname = "ngroups_max",
907 .data = &ngroups_max,
908 .maxlen = sizeof (int),
910 .proc_handler = proc_dointvec,
913 .procname = "cap_last_cap",
914 .data = (void *)&cap_last_cap,
915 .maxlen = sizeof(int),
917 .proc_handler = proc_dointvec,
919 #if defined(CONFIG_LOCKUP_DETECTOR)
921 .procname = "watchdog",
922 .data = &watchdog_user_enabled,
923 .maxlen = sizeof(int),
925 .proc_handler = proc_watchdog,
926 .extra1 = SYSCTL_ZERO,
927 .extra2 = SYSCTL_ONE,
930 .procname = "watchdog_thresh",
931 .data = &watchdog_thresh,
932 .maxlen = sizeof(int),
934 .proc_handler = proc_watchdog_thresh,
935 .extra1 = SYSCTL_ZERO,
939 .procname = "nmi_watchdog",
940 .data = &nmi_watchdog_user_enabled,
941 .maxlen = sizeof(int),
942 .mode = NMI_WATCHDOG_SYSCTL_PERM,
943 .proc_handler = proc_nmi_watchdog,
944 .extra1 = SYSCTL_ZERO,
945 .extra2 = SYSCTL_ONE,
948 .procname = "watchdog_cpumask",
949 .data = &watchdog_cpumask_bits,
952 .proc_handler = proc_watchdog_cpumask,
954 #ifdef CONFIG_SOFTLOCKUP_DETECTOR
956 .procname = "soft_watchdog",
957 .data = &soft_watchdog_user_enabled,
958 .maxlen = sizeof(int),
960 .proc_handler = proc_soft_watchdog,
961 .extra1 = SYSCTL_ZERO,
962 .extra2 = SYSCTL_ONE,
965 .procname = "softlockup_panic",
966 .data = &softlockup_panic,
967 .maxlen = sizeof(int),
969 .proc_handler = proc_dointvec_minmax,
970 .extra1 = SYSCTL_ZERO,
971 .extra2 = SYSCTL_ONE,
975 .procname = "softlockup_all_cpu_backtrace",
976 .data = &sysctl_softlockup_all_cpu_backtrace,
977 .maxlen = sizeof(int),
979 .proc_handler = proc_dointvec_minmax,
980 .extra1 = SYSCTL_ZERO,
981 .extra2 = SYSCTL_ONE,
983 #endif /* CONFIG_SMP */
985 #ifdef CONFIG_HARDLOCKUP_DETECTOR
987 .procname = "hardlockup_panic",
988 .data = &hardlockup_panic,
989 .maxlen = sizeof(int),
991 .proc_handler = proc_dointvec_minmax,
992 .extra1 = SYSCTL_ZERO,
993 .extra2 = SYSCTL_ONE,
997 .procname = "hardlockup_all_cpu_backtrace",
998 .data = &sysctl_hardlockup_all_cpu_backtrace,
999 .maxlen = sizeof(int),
1001 .proc_handler = proc_dointvec_minmax,
1002 .extra1 = SYSCTL_ZERO,
1003 .extra2 = SYSCTL_ONE,
1005 #endif /* CONFIG_SMP */
1009 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
1011 .procname = "unknown_nmi_panic",
1012 .data = &unknown_nmi_panic,
1013 .maxlen = sizeof (int),
1015 .proc_handler = proc_dointvec,
1018 #if defined(CONFIG_X86)
1020 .procname = "panic_on_unrecovered_nmi",
1021 .data = &panic_on_unrecovered_nmi,
1022 .maxlen = sizeof(int),
1024 .proc_handler = proc_dointvec,
1027 .procname = "panic_on_io_nmi",
1028 .data = &panic_on_io_nmi,
1029 .maxlen = sizeof(int),
1031 .proc_handler = proc_dointvec,
1033 #ifdef CONFIG_DEBUG_STACKOVERFLOW
1035 .procname = "panic_on_stackoverflow",
1036 .data = &sysctl_panic_on_stackoverflow,
1037 .maxlen = sizeof(int),
1039 .proc_handler = proc_dointvec,
1043 .procname = "bootloader_type",
1044 .data = &bootloader_type,
1045 .maxlen = sizeof (int),
1047 .proc_handler = proc_dointvec,
1050 .procname = "bootloader_version",
1051 .data = &bootloader_version,
1052 .maxlen = sizeof (int),
1054 .proc_handler = proc_dointvec,
1057 .procname = "io_delay_type",
1058 .data = &io_delay_type,
1059 .maxlen = sizeof(int),
1061 .proc_handler = proc_dointvec,
1064 #if defined(CONFIG_MMU)
1066 .procname = "randomize_va_space",
1067 .data = &randomize_va_space,
1068 .maxlen = sizeof(int),
1070 .proc_handler = proc_dointvec,
1073 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1075 .procname = "spin_retry",
1076 .data = &spin_retry,
1077 .maxlen = sizeof (int),
1079 .proc_handler = proc_dointvec,
1082 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1084 .procname = "acpi_video_flags",
1085 .data = &acpi_realmode_flags,
1086 .maxlen = sizeof (unsigned long),
1088 .proc_handler = proc_doulongvec_minmax,
1091 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1093 .procname = "ignore-unaligned-usertrap",
1094 .data = &no_unaligned_warning,
1095 .maxlen = sizeof (int),
1097 .proc_handler = proc_dointvec,
1102 .procname = "unaligned-dump-stack",
1103 .data = &unaligned_dump_stack,
1104 .maxlen = sizeof (int),
1106 .proc_handler = proc_dointvec,
1109 #ifdef CONFIG_DETECT_HUNG_TASK
1111 .procname = "hung_task_panic",
1112 .data = &sysctl_hung_task_panic,
1113 .maxlen = sizeof(int),
1115 .proc_handler = proc_dointvec_minmax,
1116 .extra1 = SYSCTL_ZERO,
1117 .extra2 = SYSCTL_ONE,
1120 .procname = "hung_task_check_count",
1121 .data = &sysctl_hung_task_check_count,
1122 .maxlen = sizeof(int),
1124 .proc_handler = proc_dointvec_minmax,
1125 .extra1 = SYSCTL_ZERO,
1128 .procname = "hung_task_timeout_secs",
1129 .data = &sysctl_hung_task_timeout_secs,
1130 .maxlen = sizeof(unsigned long),
1132 .proc_handler = proc_dohung_task_timeout_secs,
1133 .extra2 = &hung_task_timeout_max,
1136 .procname = "hung_task_check_interval_secs",
1137 .data = &sysctl_hung_task_check_interval_secs,
1138 .maxlen = sizeof(unsigned long),
1140 .proc_handler = proc_dohung_task_timeout_secs,
1141 .extra2 = &hung_task_timeout_max,
1144 .procname = "hung_task_warnings",
1145 .data = &sysctl_hung_task_warnings,
1146 .maxlen = sizeof(int),
1148 .proc_handler = proc_dointvec_minmax,
1152 #ifdef CONFIG_RT_MUTEXES
1154 .procname = "max_lock_depth",
1155 .data = &max_lock_depth,
1156 .maxlen = sizeof(int),
1158 .proc_handler = proc_dointvec,
1162 .procname = "poweroff_cmd",
1163 .data = &poweroff_cmd,
1164 .maxlen = POWEROFF_CMD_PATH_LEN,
1166 .proc_handler = proc_dostring,
1172 .child = key_sysctls,
1175 #ifdef CONFIG_PERF_EVENTS
1177 * User-space scripts rely on the existence of this file
1178 * as a feature check for perf_events being enabled.
1180 * So it's an ABI, do not remove!
1183 .procname = "perf_event_paranoid",
1184 .data = &sysctl_perf_event_paranoid,
1185 .maxlen = sizeof(sysctl_perf_event_paranoid),
1187 .proc_handler = proc_dointvec,
1190 .procname = "perf_event_mlock_kb",
1191 .data = &sysctl_perf_event_mlock,
1192 .maxlen = sizeof(sysctl_perf_event_mlock),
1194 .proc_handler = proc_dointvec,
1197 .procname = "perf_event_max_sample_rate",
1198 .data = &sysctl_perf_event_sample_rate,
1199 .maxlen = sizeof(sysctl_perf_event_sample_rate),
1201 .proc_handler = perf_proc_update_handler,
1202 .extra1 = SYSCTL_ONE,
1205 .procname = "perf_cpu_time_max_percent",
1206 .data = &sysctl_perf_cpu_time_max_percent,
1207 .maxlen = sizeof(sysctl_perf_cpu_time_max_percent),
1209 .proc_handler = perf_cpu_time_max_percent_handler,
1210 .extra1 = SYSCTL_ZERO,
1211 .extra2 = &one_hundred,
1214 .procname = "perf_event_max_stack",
1215 .data = &sysctl_perf_event_max_stack,
1216 .maxlen = sizeof(sysctl_perf_event_max_stack),
1218 .proc_handler = perf_event_max_stack_handler,
1219 .extra1 = SYSCTL_ZERO,
1220 .extra2 = &six_hundred_forty_kb,
1223 .procname = "perf_event_max_contexts_per_stack",
1224 .data = &sysctl_perf_event_max_contexts_per_stack,
1225 .maxlen = sizeof(sysctl_perf_event_max_contexts_per_stack),
1227 .proc_handler = perf_event_max_stack_handler,
1228 .extra1 = SYSCTL_ZERO,
1229 .extra2 = &one_thousand,
1233 .procname = "panic_on_warn",
1234 .data = &panic_on_warn,
1235 .maxlen = sizeof(int),
1237 .proc_handler = proc_dointvec_minmax,
1238 .extra1 = SYSCTL_ZERO,
1239 .extra2 = SYSCTL_ONE,
1241 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1243 .procname = "timer_migration",
1244 .data = &sysctl_timer_migration,
1245 .maxlen = sizeof(unsigned int),
1247 .proc_handler = timer_migration_handler,
1248 .extra1 = SYSCTL_ZERO,
1249 .extra2 = SYSCTL_ONE,
1252 #ifdef CONFIG_BPF_SYSCALL
1254 .procname = "unprivileged_bpf_disabled",
1255 .data = &sysctl_unprivileged_bpf_disabled,
1256 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled),
1258 /* only handle a transition from default "0" to "1" */
1259 .proc_handler = proc_dointvec_minmax,
1260 .extra1 = SYSCTL_ONE,
1261 .extra2 = SYSCTL_ONE,
1264 .procname = "bpf_stats_enabled",
1265 .data = &bpf_stats_enabled_key.key,
1266 .maxlen = sizeof(bpf_stats_enabled_key),
1268 .proc_handler = proc_do_static_key,
1271 #if defined(CONFIG_TREE_RCU) || defined(CONFIG_PREEMPT_RCU)
1273 .procname = "panic_on_rcu_stall",
1274 .data = &sysctl_panic_on_rcu_stall,
1275 .maxlen = sizeof(sysctl_panic_on_rcu_stall),
1277 .proc_handler = proc_dointvec_minmax,
1278 .extra1 = SYSCTL_ZERO,
1279 .extra2 = SYSCTL_ONE,
1282 #ifdef CONFIG_STACKLEAK_RUNTIME_DISABLE
1284 .procname = "stack_erasing",
1286 .maxlen = sizeof(int),
1288 .proc_handler = stack_erasing_sysctl,
1289 .extra1 = SYSCTL_ZERO,
1290 .extra2 = SYSCTL_ONE,
1296 static struct ctl_table vm_table[] = {
1298 .procname = "overcommit_memory",
1299 .data = &sysctl_overcommit_memory,
1300 .maxlen = sizeof(sysctl_overcommit_memory),
1302 .proc_handler = proc_dointvec_minmax,
1303 .extra1 = SYSCTL_ZERO,
1307 .procname = "panic_on_oom",
1308 .data = &sysctl_panic_on_oom,
1309 .maxlen = sizeof(sysctl_panic_on_oom),
1311 .proc_handler = proc_dointvec_minmax,
1312 .extra1 = SYSCTL_ZERO,
1316 .procname = "oom_kill_allocating_task",
1317 .data = &sysctl_oom_kill_allocating_task,
1318 .maxlen = sizeof(sysctl_oom_kill_allocating_task),
1320 .proc_handler = proc_dointvec,
1323 .procname = "oom_dump_tasks",
1324 .data = &sysctl_oom_dump_tasks,
1325 .maxlen = sizeof(sysctl_oom_dump_tasks),
1327 .proc_handler = proc_dointvec,
1330 .procname = "overcommit_ratio",
1331 .data = &sysctl_overcommit_ratio,
1332 .maxlen = sizeof(sysctl_overcommit_ratio),
1334 .proc_handler = overcommit_ratio_handler,
1337 .procname = "overcommit_kbytes",
1338 .data = &sysctl_overcommit_kbytes,
1339 .maxlen = sizeof(sysctl_overcommit_kbytes),
1341 .proc_handler = overcommit_kbytes_handler,
1344 .procname = "page-cluster",
1345 .data = &page_cluster,
1346 .maxlen = sizeof(int),
1348 .proc_handler = proc_dointvec_minmax,
1349 .extra1 = SYSCTL_ZERO,
1352 .procname = "dirty_background_ratio",
1353 .data = &dirty_background_ratio,
1354 .maxlen = sizeof(dirty_background_ratio),
1356 .proc_handler = dirty_background_ratio_handler,
1357 .extra1 = SYSCTL_ZERO,
1358 .extra2 = &one_hundred,
1361 .procname = "dirty_background_bytes",
1362 .data = &dirty_background_bytes,
1363 .maxlen = sizeof(dirty_background_bytes),
1365 .proc_handler = dirty_background_bytes_handler,
1369 .procname = "dirty_ratio",
1370 .data = &vm_dirty_ratio,
1371 .maxlen = sizeof(vm_dirty_ratio),
1373 .proc_handler = dirty_ratio_handler,
1374 .extra1 = SYSCTL_ZERO,
1375 .extra2 = &one_hundred,
1378 .procname = "dirty_bytes",
1379 .data = &vm_dirty_bytes,
1380 .maxlen = sizeof(vm_dirty_bytes),
1382 .proc_handler = dirty_bytes_handler,
1383 .extra1 = &dirty_bytes_min,
1386 .procname = "dirty_writeback_centisecs",
1387 .data = &dirty_writeback_interval,
1388 .maxlen = sizeof(dirty_writeback_interval),
1390 .proc_handler = dirty_writeback_centisecs_handler,
1393 .procname = "dirty_expire_centisecs",
1394 .data = &dirty_expire_interval,
1395 .maxlen = sizeof(dirty_expire_interval),
1397 .proc_handler = proc_dointvec_minmax,
1398 .extra1 = SYSCTL_ZERO,
1401 .procname = "dirtytime_expire_seconds",
1402 .data = &dirtytime_expire_interval,
1403 .maxlen = sizeof(dirtytime_expire_interval),
1405 .proc_handler = dirtytime_interval_handler,
1406 .extra1 = SYSCTL_ZERO,
1409 .procname = "swappiness",
1410 .data = &vm_swappiness,
1411 .maxlen = sizeof(vm_swappiness),
1413 .proc_handler = proc_dointvec_minmax,
1414 .extra1 = SYSCTL_ZERO,
1415 .extra2 = &one_hundred,
1417 #ifdef CONFIG_HUGETLB_PAGE
1419 .procname = "nr_hugepages",
1421 .maxlen = sizeof(unsigned long),
1423 .proc_handler = hugetlb_sysctl_handler,
1427 .procname = "nr_hugepages_mempolicy",
1429 .maxlen = sizeof(unsigned long),
1431 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
1434 .procname = "numa_stat",
1435 .data = &sysctl_vm_numa_stat,
1436 .maxlen = sizeof(int),
1438 .proc_handler = sysctl_vm_numa_stat_handler,
1439 .extra1 = SYSCTL_ZERO,
1440 .extra2 = SYSCTL_ONE,
1444 .procname = "hugetlb_shm_group",
1445 .data = &sysctl_hugetlb_shm_group,
1446 .maxlen = sizeof(gid_t),
1448 .proc_handler = proc_dointvec,
1451 .procname = "nr_overcommit_hugepages",
1453 .maxlen = sizeof(unsigned long),
1455 .proc_handler = hugetlb_overcommit_handler,
1459 .procname = "lowmem_reserve_ratio",
1460 .data = &sysctl_lowmem_reserve_ratio,
1461 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
1463 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
1466 .procname = "drop_caches",
1467 .data = &sysctl_drop_caches,
1468 .maxlen = sizeof(int),
1470 .proc_handler = drop_caches_sysctl_handler,
1471 .extra1 = SYSCTL_ONE,
1474 #ifdef CONFIG_COMPACTION
1476 .procname = "compact_memory",
1477 .data = &sysctl_compact_memory,
1478 .maxlen = sizeof(int),
1480 .proc_handler = sysctl_compaction_handler,
1483 .procname = "extfrag_threshold",
1484 .data = &sysctl_extfrag_threshold,
1485 .maxlen = sizeof(int),
1487 .proc_handler = proc_dointvec_minmax,
1488 .extra1 = &min_extfrag_threshold,
1489 .extra2 = &max_extfrag_threshold,
1492 .procname = "compact_unevictable_allowed",
1493 .data = &sysctl_compact_unevictable_allowed,
1494 .maxlen = sizeof(int),
1496 .proc_handler = proc_dointvec,
1497 .extra1 = SYSCTL_ZERO,
1498 .extra2 = SYSCTL_ONE,
1501 #endif /* CONFIG_COMPACTION */
1503 .procname = "min_free_kbytes",
1504 .data = &min_free_kbytes,
1505 .maxlen = sizeof(min_free_kbytes),
1507 .proc_handler = min_free_kbytes_sysctl_handler,
1508 .extra1 = SYSCTL_ZERO,
1511 .procname = "watermark_boost_factor",
1512 .data = &watermark_boost_factor,
1513 .maxlen = sizeof(watermark_boost_factor),
1515 .proc_handler = watermark_boost_factor_sysctl_handler,
1516 .extra1 = SYSCTL_ZERO,
1519 .procname = "watermark_scale_factor",
1520 .data = &watermark_scale_factor,
1521 .maxlen = sizeof(watermark_scale_factor),
1523 .proc_handler = watermark_scale_factor_sysctl_handler,
1524 .extra1 = SYSCTL_ONE,
1525 .extra2 = &one_thousand,
1528 .procname = "percpu_pagelist_fraction",
1529 .data = &percpu_pagelist_fraction,
1530 .maxlen = sizeof(percpu_pagelist_fraction),
1532 .proc_handler = percpu_pagelist_fraction_sysctl_handler,
1533 .extra1 = SYSCTL_ZERO,
1537 .procname = "max_map_count",
1538 .data = &sysctl_max_map_count,
1539 .maxlen = sizeof(sysctl_max_map_count),
1541 .proc_handler = proc_dointvec_minmax,
1542 .extra1 = SYSCTL_ZERO,
1546 .procname = "nr_trim_pages",
1547 .data = &sysctl_nr_trim_pages,
1548 .maxlen = sizeof(sysctl_nr_trim_pages),
1550 .proc_handler = proc_dointvec_minmax,
1551 .extra1 = SYSCTL_ZERO,
1555 .procname = "laptop_mode",
1556 .data = &laptop_mode,
1557 .maxlen = sizeof(laptop_mode),
1559 .proc_handler = proc_dointvec_jiffies,
1562 .procname = "block_dump",
1563 .data = &block_dump,
1564 .maxlen = sizeof(block_dump),
1566 .proc_handler = proc_dointvec,
1567 .extra1 = SYSCTL_ZERO,
1570 .procname = "vfs_cache_pressure",
1571 .data = &sysctl_vfs_cache_pressure,
1572 .maxlen = sizeof(sysctl_vfs_cache_pressure),
1574 .proc_handler = proc_dointvec,
1575 .extra1 = SYSCTL_ZERO,
1577 #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
1578 defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
1580 .procname = "legacy_va_layout",
1581 .data = &sysctl_legacy_va_layout,
1582 .maxlen = sizeof(sysctl_legacy_va_layout),
1584 .proc_handler = proc_dointvec,
1585 .extra1 = SYSCTL_ZERO,
1590 .procname = "zone_reclaim_mode",
1591 .data = &node_reclaim_mode,
1592 .maxlen = sizeof(node_reclaim_mode),
1594 .proc_handler = proc_dointvec,
1595 .extra1 = SYSCTL_ZERO,
1598 .procname = "min_unmapped_ratio",
1599 .data = &sysctl_min_unmapped_ratio,
1600 .maxlen = sizeof(sysctl_min_unmapped_ratio),
1602 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
1603 .extra1 = SYSCTL_ZERO,
1604 .extra2 = &one_hundred,
1607 .procname = "min_slab_ratio",
1608 .data = &sysctl_min_slab_ratio,
1609 .maxlen = sizeof(sysctl_min_slab_ratio),
1611 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
1612 .extra1 = SYSCTL_ZERO,
1613 .extra2 = &one_hundred,
1618 .procname = "stat_interval",
1619 .data = &sysctl_stat_interval,
1620 .maxlen = sizeof(sysctl_stat_interval),
1622 .proc_handler = proc_dointvec_jiffies,
1625 .procname = "stat_refresh",
1629 .proc_handler = vmstat_refresh,
1634 .procname = "mmap_min_addr",
1635 .data = &dac_mmap_min_addr,
1636 .maxlen = sizeof(unsigned long),
1638 .proc_handler = mmap_min_addr_handler,
1643 .procname = "numa_zonelist_order",
1644 .data = &numa_zonelist_order,
1645 .maxlen = NUMA_ZONELIST_ORDER_LEN,
1647 .proc_handler = numa_zonelist_order_handler,
1650 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1651 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1653 .procname = "vdso_enabled",
1654 #ifdef CONFIG_X86_32
1655 .data = &vdso32_enabled,
1656 .maxlen = sizeof(vdso32_enabled),
1658 .data = &vdso_enabled,
1659 .maxlen = sizeof(vdso_enabled),
1662 .proc_handler = proc_dointvec,
1663 .extra1 = SYSCTL_ZERO,
1666 #ifdef CONFIG_HIGHMEM
1668 .procname = "highmem_is_dirtyable",
1669 .data = &vm_highmem_is_dirtyable,
1670 .maxlen = sizeof(vm_highmem_is_dirtyable),
1672 .proc_handler = proc_dointvec_minmax,
1673 .extra1 = SYSCTL_ZERO,
1674 .extra2 = SYSCTL_ONE,
1677 #ifdef CONFIG_MEMORY_FAILURE
1679 .procname = "memory_failure_early_kill",
1680 .data = &sysctl_memory_failure_early_kill,
1681 .maxlen = sizeof(sysctl_memory_failure_early_kill),
1683 .proc_handler = proc_dointvec_minmax,
1684 .extra1 = SYSCTL_ZERO,
1685 .extra2 = SYSCTL_ONE,
1688 .procname = "memory_failure_recovery",
1689 .data = &sysctl_memory_failure_recovery,
1690 .maxlen = sizeof(sysctl_memory_failure_recovery),
1692 .proc_handler = proc_dointvec_minmax,
1693 .extra1 = SYSCTL_ZERO,
1694 .extra2 = SYSCTL_ONE,
1698 .procname = "user_reserve_kbytes",
1699 .data = &sysctl_user_reserve_kbytes,
1700 .maxlen = sizeof(sysctl_user_reserve_kbytes),
1702 .proc_handler = proc_doulongvec_minmax,
1705 .procname = "admin_reserve_kbytes",
1706 .data = &sysctl_admin_reserve_kbytes,
1707 .maxlen = sizeof(sysctl_admin_reserve_kbytes),
1709 .proc_handler = proc_doulongvec_minmax,
1711 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
1713 .procname = "mmap_rnd_bits",
1714 .data = &mmap_rnd_bits,
1715 .maxlen = sizeof(mmap_rnd_bits),
1717 .proc_handler = proc_dointvec_minmax,
1718 .extra1 = (void *)&mmap_rnd_bits_min,
1719 .extra2 = (void *)&mmap_rnd_bits_max,
1722 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
1724 .procname = "mmap_rnd_compat_bits",
1725 .data = &mmap_rnd_compat_bits,
1726 .maxlen = sizeof(mmap_rnd_compat_bits),
1728 .proc_handler = proc_dointvec_minmax,
1729 .extra1 = (void *)&mmap_rnd_compat_bits_min,
1730 .extra2 = (void *)&mmap_rnd_compat_bits_max,
1733 #ifdef CONFIG_USERFAULTFD
1735 .procname = "unprivileged_userfaultfd",
1736 .data = &sysctl_unprivileged_userfaultfd,
1737 .maxlen = sizeof(sysctl_unprivileged_userfaultfd),
1739 .proc_handler = proc_dointvec_minmax,
1740 .extra1 = SYSCTL_ZERO,
1741 .extra2 = SYSCTL_ONE,
1747 static struct ctl_table fs_table[] = {
1749 .procname = "inode-nr",
1750 .data = &inodes_stat,
1751 .maxlen = 2*sizeof(long),
1753 .proc_handler = proc_nr_inodes,
1756 .procname = "inode-state",
1757 .data = &inodes_stat,
1758 .maxlen = 7*sizeof(long),
1760 .proc_handler = proc_nr_inodes,
1763 .procname = "file-nr",
1764 .data = &files_stat,
1765 .maxlen = sizeof(files_stat),
1767 .proc_handler = proc_nr_files,
1770 .procname = "file-max",
1771 .data = &files_stat.max_files,
1772 .maxlen = sizeof(files_stat.max_files),
1774 .proc_handler = proc_doulongvec_minmax,
1776 .extra2 = &long_max,
1779 .procname = "nr_open",
1780 .data = &sysctl_nr_open,
1781 .maxlen = sizeof(unsigned int),
1783 .proc_handler = proc_dointvec_minmax,
1784 .extra1 = &sysctl_nr_open_min,
1785 .extra2 = &sysctl_nr_open_max,
1788 .procname = "dentry-state",
1789 .data = &dentry_stat,
1790 .maxlen = 6*sizeof(long),
1792 .proc_handler = proc_nr_dentry,
1795 .procname = "overflowuid",
1796 .data = &fs_overflowuid,
1797 .maxlen = sizeof(int),
1799 .proc_handler = proc_dointvec_minmax,
1800 .extra1 = &minolduid,
1801 .extra2 = &maxolduid,
1804 .procname = "overflowgid",
1805 .data = &fs_overflowgid,
1806 .maxlen = sizeof(int),
1808 .proc_handler = proc_dointvec_minmax,
1809 .extra1 = &minolduid,
1810 .extra2 = &maxolduid,
1812 #ifdef CONFIG_FILE_LOCKING
1814 .procname = "leases-enable",
1815 .data = &leases_enable,
1816 .maxlen = sizeof(int),
1818 .proc_handler = proc_dointvec,
1821 #ifdef CONFIG_DNOTIFY
1823 .procname = "dir-notify-enable",
1824 .data = &dir_notify_enable,
1825 .maxlen = sizeof(int),
1827 .proc_handler = proc_dointvec,
1831 #ifdef CONFIG_FILE_LOCKING
1833 .procname = "lease-break-time",
1834 .data = &lease_break_time,
1835 .maxlen = sizeof(int),
1837 .proc_handler = proc_dointvec,
1842 .procname = "aio-nr",
1844 .maxlen = sizeof(aio_nr),
1846 .proc_handler = proc_doulongvec_minmax,
1849 .procname = "aio-max-nr",
1850 .data = &aio_max_nr,
1851 .maxlen = sizeof(aio_max_nr),
1853 .proc_handler = proc_doulongvec_minmax,
1855 #endif /* CONFIG_AIO */
1856 #ifdef CONFIG_INOTIFY_USER
1858 .procname = "inotify",
1860 .child = inotify_table,
1865 .procname = "epoll",
1867 .child = epoll_table,
1872 .procname = "protected_symlinks",
1873 .data = &sysctl_protected_symlinks,
1874 .maxlen = sizeof(int),
1876 .proc_handler = proc_dointvec_minmax,
1877 .extra1 = SYSCTL_ZERO,
1878 .extra2 = SYSCTL_ONE,
1881 .procname = "protected_hardlinks",
1882 .data = &sysctl_protected_hardlinks,
1883 .maxlen = sizeof(int),
1885 .proc_handler = proc_dointvec_minmax,
1886 .extra1 = SYSCTL_ZERO,
1887 .extra2 = SYSCTL_ONE,
1890 .procname = "protected_fifos",
1891 .data = &sysctl_protected_fifos,
1892 .maxlen = sizeof(int),
1894 .proc_handler = proc_dointvec_minmax,
1895 .extra1 = SYSCTL_ZERO,
1899 .procname = "protected_regular",
1900 .data = &sysctl_protected_regular,
1901 .maxlen = sizeof(int),
1903 .proc_handler = proc_dointvec_minmax,
1904 .extra1 = SYSCTL_ZERO,
1908 .procname = "suid_dumpable",
1909 .data = &suid_dumpable,
1910 .maxlen = sizeof(int),
1912 .proc_handler = proc_dointvec_minmax_coredump,
1913 .extra1 = SYSCTL_ZERO,
1916 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1918 .procname = "binfmt_misc",
1920 .child = sysctl_mount_point,
1924 .procname = "pipe-max-size",
1925 .data = &pipe_max_size,
1926 .maxlen = sizeof(pipe_max_size),
1928 .proc_handler = proc_dopipe_max_size,
1931 .procname = "pipe-user-pages-hard",
1932 .data = &pipe_user_pages_hard,
1933 .maxlen = sizeof(pipe_user_pages_hard),
1935 .proc_handler = proc_doulongvec_minmax,
1938 .procname = "pipe-user-pages-soft",
1939 .data = &pipe_user_pages_soft,
1940 .maxlen = sizeof(pipe_user_pages_soft),
1942 .proc_handler = proc_doulongvec_minmax,
1945 .procname = "mount-max",
1946 .data = &sysctl_mount_max,
1947 .maxlen = sizeof(unsigned int),
1949 .proc_handler = proc_dointvec_minmax,
1950 .extra1 = SYSCTL_ONE,
1955 static struct ctl_table debug_table[] = {
1956 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1958 .procname = "exception-trace",
1959 .data = &show_unhandled_signals,
1960 .maxlen = sizeof(int),
1962 .proc_handler = proc_dointvec
1965 #if defined(CONFIG_OPTPROBES)
1967 .procname = "kprobes-optimization",
1968 .data = &sysctl_kprobes_optimization,
1969 .maxlen = sizeof(int),
1971 .proc_handler = proc_kprobes_optimization_handler,
1972 .extra1 = SYSCTL_ZERO,
1973 .extra2 = SYSCTL_ONE,
1979 static struct ctl_table dev_table[] = {
1983 int __init sysctl_init(void)
1985 struct ctl_table_header *hdr;
1987 hdr = register_sysctl_table(sysctl_base_table);
1988 kmemleak_not_leak(hdr);
1992 #endif /* CONFIG_SYSCTL */
1998 #ifdef CONFIG_PROC_SYSCTL
2000 static int _proc_do_string(char *data, int maxlen, int write,
2001 char __user *buffer,
2002 size_t *lenp, loff_t *ppos)
2008 if (!data || !maxlen || !*lenp) {
2014 if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
2015 /* Only continue writes not past the end of buffer. */
2017 if (len > maxlen - 1)
2024 /* Start writing from beginning of buffer. */
2030 while ((p - buffer) < *lenp && len < maxlen - 1) {
2031 if (get_user(c, p++))
2033 if (c == 0 || c == '\n')
2054 if (copy_to_user(buffer, data, len))
2057 if (put_user('\n', buffer + len))
2067 static void warn_sysctl_write(struct ctl_table *table)
2069 pr_warn_once("%s wrote to %s when file position was not 0!\n"
2070 "This will not be supported in the future. To silence this\n"
2071 "warning, set kernel.sysctl_writes_strict = -1\n",
2072 current->comm, table->procname);
2076 * proc_first_pos_non_zero_ignore - check if first position is allowed
2077 * @ppos: file position
2078 * @table: the sysctl table
2080 * Returns true if the first position is non-zero and the sysctl_writes_strict
2081 * mode indicates this is not allowed for numeric input types. String proc
2082 * handlers can ignore the return value.
2084 static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
2085 struct ctl_table *table)
2090 switch (sysctl_writes_strict) {
2091 case SYSCTL_WRITES_STRICT:
2093 case SYSCTL_WRITES_WARN:
2094 warn_sysctl_write(table);
2102 * proc_dostring - read a string sysctl
2103 * @table: the sysctl table
2104 * @write: %TRUE if this is a write to the sysctl file
2105 * @buffer: the user buffer
2106 * @lenp: the size of the user buffer
2107 * @ppos: file position
2109 * Reads/writes a string from/to the user buffer. If the kernel
2110 * buffer provided is not large enough to hold the string, the
2111 * string is truncated. The copied string is %NULL-terminated.
2112 * If the string is being read by the user process, it is copied
2113 * and a newline '\n' is added. It is truncated if the buffer is
2116 * Returns 0 on success.
2118 int proc_dostring(struct ctl_table *table, int write,
2119 void __user *buffer, size_t *lenp, loff_t *ppos)
2122 proc_first_pos_non_zero_ignore(ppos, table);
2124 return _proc_do_string((char *)(table->data), table->maxlen, write,
2125 (char __user *)buffer, lenp, ppos);
2128 static size_t proc_skip_spaces(char **buf)
2131 char *tmp = skip_spaces(*buf);
2137 static void proc_skip_char(char **buf, size_t *size, const char v)
2148 * strtoul_lenient - parse an ASCII formatted integer from a buffer and only
2151 * @cp: kernel buffer containing the string to parse
2152 * @endp: pointer to store the trailing characters
2153 * @base: the base to use
2154 * @res: where the parsed integer will be stored
2156 * In case of success 0 is returned and @res will contain the parsed integer,
2157 * @endp will hold any trailing characters.
2158 * This function will fail the parse on overflow. If there wasn't an overflow
2159 * the function will defer the decision what characters count as invalid to the
2162 static int strtoul_lenient(const char *cp, char **endp, unsigned int base,
2165 unsigned long long result;
2168 cp = _parse_integer_fixup_radix(cp, &base);
2169 rv = _parse_integer(cp, base, &result);
2170 if ((rv & KSTRTOX_OVERFLOW) || (result != (unsigned long)result))
2178 *res = (unsigned long)result;
2182 #define TMPBUFLEN 22
2184 * proc_get_long - reads an ASCII formatted integer from a user buffer
2186 * @buf: a kernel buffer
2187 * @size: size of the kernel buffer
2188 * @val: this is where the number will be stored
2189 * @neg: set to %TRUE if number is negative
2190 * @perm_tr: a vector which contains the allowed trailers
2191 * @perm_tr_len: size of the perm_tr vector
2192 * @tr: pointer to store the trailer character
2194 * In case of success %0 is returned and @buf and @size are updated with
2195 * the amount of bytes read. If @tr is non-NULL and a trailing
2196 * character exists (size is non-zero after returning from this
2197 * function), @tr is updated with the trailing character.
2199 static int proc_get_long(char **buf, size_t *size,
2200 unsigned long *val, bool *neg,
2201 const char *perm_tr, unsigned perm_tr_len, char *tr)
2204 char *p, tmp[TMPBUFLEN];
2210 if (len > TMPBUFLEN - 1)
2211 len = TMPBUFLEN - 1;
2213 memcpy(tmp, *buf, len);
2217 if (*p == '-' && *size > 1) {
2225 if (strtoul_lenient(p, &p, 0, val))
2230 /* We don't know if the next char is whitespace thus we may accept
2231 * invalid integers (e.g. 1234...a) or two integers instead of one
2232 * (e.g. 123...1). So lets not allow such large numbers. */
2233 if (len == TMPBUFLEN - 1)
2236 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2239 if (tr && (len < *size))
2249 * proc_put_long - converts an integer to a decimal ASCII formatted string
2251 * @buf: the user buffer
2252 * @size: the size of the user buffer
2253 * @val: the integer to be converted
2254 * @neg: sign of the number, %TRUE for negative
2256 * In case of success %0 is returned and @buf and @size are updated with
2257 * the amount of bytes written.
2259 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2263 char tmp[TMPBUFLEN], *p = tmp;
2265 sprintf(p, "%s%lu", neg ? "-" : "", val);
2269 if (copy_to_user(*buf, tmp, len))
2277 static int proc_put_char(void __user **buf, size_t *size, char c)
2280 char __user **buffer = (char __user **)buf;
2281 if (put_user(c, *buffer))
2283 (*size)--, (*buffer)++;
2289 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2291 int write, void *data)
2295 if (*lvalp > (unsigned long) INT_MAX + 1)
2299 if (*lvalp > (unsigned long) INT_MAX)
2307 *lvalp = -(unsigned long)val;
2310 *lvalp = (unsigned long)val;
2316 static int do_proc_douintvec_conv(unsigned long *lvalp,
2318 int write, void *data)
2321 if (*lvalp > UINT_MAX)
2325 unsigned int val = *valp;
2326 *lvalp = (unsigned long)val;
2331 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2333 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2334 int write, void __user *buffer,
2335 size_t *lenp, loff_t *ppos,
2336 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2337 int write, void *data),
2340 int *i, vleft, first = 1, err = 0;
2342 char *kbuf = NULL, *p;
2344 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2349 i = (int *) tbl_data;
2350 vleft = table->maxlen / sizeof(*i);
2354 conv = do_proc_dointvec_conv;
2357 if (proc_first_pos_non_zero_ignore(ppos, table))
2360 if (left > PAGE_SIZE - 1)
2361 left = PAGE_SIZE - 1;
2362 p = kbuf = memdup_user_nul(buffer, left);
2364 return PTR_ERR(kbuf);
2367 for (; left && vleft--; i++, first=0) {
2372 left -= proc_skip_spaces(&p);
2376 err = proc_get_long(&p, &left, &lval, &neg,
2378 sizeof(proc_wspace_sep), NULL);
2381 if (conv(&neg, &lval, i, 1, data)) {
2386 if (conv(&neg, &lval, i, 0, data)) {
2391 err = proc_put_char(&buffer, &left, '\t');
2394 err = proc_put_long(&buffer, &left, lval, neg);
2400 if (!write && !first && left && !err)
2401 err = proc_put_char(&buffer, &left, '\n');
2402 if (write && !err && left)
2403 left -= proc_skip_spaces(&p);
2407 return err ? : -EINVAL;
2415 static int do_proc_dointvec(struct ctl_table *table, int write,
2416 void __user *buffer, size_t *lenp, loff_t *ppos,
2417 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2418 int write, void *data),
2421 return __do_proc_dointvec(table->data, table, write,
2422 buffer, lenp, ppos, conv, data);
2425 static int do_proc_douintvec_w(unsigned int *tbl_data,
2426 struct ctl_table *table,
2427 void __user *buffer,
2428 size_t *lenp, loff_t *ppos,
2429 int (*conv)(unsigned long *lvalp,
2431 int write, void *data),
2438 char *kbuf = NULL, *p;
2442 if (proc_first_pos_non_zero_ignore(ppos, table))
2445 if (left > PAGE_SIZE - 1)
2446 left = PAGE_SIZE - 1;
2448 p = kbuf = memdup_user_nul(buffer, left);
2452 left -= proc_skip_spaces(&p);
2458 err = proc_get_long(&p, &left, &lval, &neg,
2460 sizeof(proc_wspace_sep), NULL);
2466 if (conv(&lval, tbl_data, 1, data)) {
2472 left -= proc_skip_spaces(&p);
2481 /* This is in keeping with old __do_proc_dointvec() */
2487 static int do_proc_douintvec_r(unsigned int *tbl_data, void __user *buffer,
2488 size_t *lenp, loff_t *ppos,
2489 int (*conv)(unsigned long *lvalp,
2491 int write, void *data),
2500 if (conv(&lval, tbl_data, 0, data)) {
2505 err = proc_put_long(&buffer, &left, lval, false);
2509 err = proc_put_char(&buffer, &left, '\n');
2518 static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
2519 int write, void __user *buffer,
2520 size_t *lenp, loff_t *ppos,
2521 int (*conv)(unsigned long *lvalp,
2523 int write, void *data),
2526 unsigned int *i, vleft;
2528 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2533 i = (unsigned int *) tbl_data;
2534 vleft = table->maxlen / sizeof(*i);
2537 * Arrays are not supported, keep this simple. *Do not* add
2546 conv = do_proc_douintvec_conv;
2549 return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
2551 return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
2554 static int do_proc_douintvec(struct ctl_table *table, int write,
2555 void __user *buffer, size_t *lenp, loff_t *ppos,
2556 int (*conv)(unsigned long *lvalp,
2558 int write, void *data),
2561 return __do_proc_douintvec(table->data, table, write,
2562 buffer, lenp, ppos, conv, data);
2566 * proc_dointvec - read a vector of integers
2567 * @table: the sysctl table
2568 * @write: %TRUE if this is a write to the sysctl file
2569 * @buffer: the user buffer
2570 * @lenp: the size of the user buffer
2571 * @ppos: file position
2573 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2574 * values from/to the user buffer, treated as an ASCII string.
2576 * Returns 0 on success.
2578 int proc_dointvec(struct ctl_table *table, int write,
2579 void __user *buffer, size_t *lenp, loff_t *ppos)
2581 return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
2585 * proc_douintvec - read a vector of unsigned integers
2586 * @table: the sysctl table
2587 * @write: %TRUE if this is a write to the sysctl file
2588 * @buffer: the user buffer
2589 * @lenp: the size of the user buffer
2590 * @ppos: file position
2592 * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2593 * values from/to the user buffer, treated as an ASCII string.
2595 * Returns 0 on success.
2597 int proc_douintvec(struct ctl_table *table, int write,
2598 void __user *buffer, size_t *lenp, loff_t *ppos)
2600 return do_proc_douintvec(table, write, buffer, lenp, ppos,
2601 do_proc_douintvec_conv, NULL);
2605 * Taint values can only be increased
2606 * This means we can safely use a temporary.
2608 static int proc_taint(struct ctl_table *table, int write,
2609 void __user *buffer, size_t *lenp, loff_t *ppos)
2612 unsigned long tmptaint = get_taint();
2615 if (write && !capable(CAP_SYS_ADMIN))
2620 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2626 * Poor man's atomic or. Not worth adding a primitive
2627 * to everyone's atomic.h for this
2630 for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2631 if ((tmptaint >> i) & 1)
2632 add_taint(i, LOCKDEP_STILL_OK);
2639 #ifdef CONFIG_PRINTK
2640 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2641 void __user *buffer, size_t *lenp, loff_t *ppos)
2643 if (write && !capable(CAP_SYS_ADMIN))
2646 return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2651 * struct do_proc_dointvec_minmax_conv_param - proc_dointvec_minmax() range checking structure
2652 * @min: pointer to minimum allowable value
2653 * @max: pointer to maximum allowable value
2655 * The do_proc_dointvec_minmax_conv_param structure provides the
2656 * minimum and maximum values for doing range checking for those sysctl
2657 * parameters that use the proc_dointvec_minmax() handler.
2659 struct do_proc_dointvec_minmax_conv_param {
2664 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2666 int write, void *data)
2669 struct do_proc_dointvec_minmax_conv_param *param = data;
2671 * If writing, first do so via a temporary local int so we can
2672 * bounds-check it before touching *valp.
2674 int *ip = write ? &tmp : valp;
2676 ret = do_proc_dointvec_conv(negp, lvalp, ip, write, data);
2681 if ((param->min && *param->min > tmp) ||
2682 (param->max && *param->max < tmp))
2691 * proc_dointvec_minmax - read a vector of integers with min/max values
2692 * @table: the sysctl table
2693 * @write: %TRUE if this is a write to the sysctl file
2694 * @buffer: the user buffer
2695 * @lenp: the size of the user buffer
2696 * @ppos: file position
2698 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2699 * values from/to the user buffer, treated as an ASCII string.
2701 * This routine will ensure the values are within the range specified by
2702 * table->extra1 (min) and table->extra2 (max).
2704 * Returns 0 on success or -EINVAL on write when the range check fails.
2706 int proc_dointvec_minmax(struct ctl_table *table, int write,
2707 void __user *buffer, size_t *lenp, loff_t *ppos)
2709 struct do_proc_dointvec_minmax_conv_param param = {
2710 .min = (int *) table->extra1,
2711 .max = (int *) table->extra2,
2713 return do_proc_dointvec(table, write, buffer, lenp, ppos,
2714 do_proc_dointvec_minmax_conv, ¶m);
2718 * struct do_proc_douintvec_minmax_conv_param - proc_douintvec_minmax() range checking structure
2719 * @min: pointer to minimum allowable value
2720 * @max: pointer to maximum allowable value
2722 * The do_proc_douintvec_minmax_conv_param structure provides the
2723 * minimum and maximum values for doing range checking for those sysctl
2724 * parameters that use the proc_douintvec_minmax() handler.
2726 struct do_proc_douintvec_minmax_conv_param {
2731 static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
2733 int write, void *data)
2737 struct do_proc_douintvec_minmax_conv_param *param = data;
2738 /* write via temporary local uint for bounds-checking */
2739 unsigned int *up = write ? &tmp : valp;
2741 ret = do_proc_douintvec_conv(lvalp, up, write, data);
2746 if ((param->min && *param->min > tmp) ||
2747 (param->max && *param->max < tmp))
2757 * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
2758 * @table: the sysctl table
2759 * @write: %TRUE if this is a write to the sysctl file
2760 * @buffer: the user buffer
2761 * @lenp: the size of the user buffer
2762 * @ppos: file position
2764 * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2765 * values from/to the user buffer, treated as an ASCII string. Negative
2766 * strings are not allowed.
2768 * This routine will ensure the values are within the range specified by
2769 * table->extra1 (min) and table->extra2 (max). There is a final sanity
2770 * check for UINT_MAX to avoid having to support wrap around uses from
2773 * Returns 0 on success or -ERANGE on write when the range check fails.
2775 int proc_douintvec_minmax(struct ctl_table *table, int write,
2776 void __user *buffer, size_t *lenp, loff_t *ppos)
2778 struct do_proc_douintvec_minmax_conv_param param = {
2779 .min = (unsigned int *) table->extra1,
2780 .max = (unsigned int *) table->extra2,
2782 return do_proc_douintvec(table, write, buffer, lenp, ppos,
2783 do_proc_douintvec_minmax_conv, ¶m);
2786 static int do_proc_dopipe_max_size_conv(unsigned long *lvalp,
2788 int write, void *data)
2793 val = round_pipe_size(*lvalp);
2799 unsigned int val = *valp;
2800 *lvalp = (unsigned long) val;
2806 static int proc_dopipe_max_size(struct ctl_table *table, int write,
2807 void __user *buffer, size_t *lenp, loff_t *ppos)
2809 return do_proc_douintvec(table, write, buffer, lenp, ppos,
2810 do_proc_dopipe_max_size_conv, NULL);
2813 static void validate_coredump_safety(void)
2815 #ifdef CONFIG_COREDUMP
2816 if (suid_dumpable == SUID_DUMP_ROOT &&
2817 core_pattern[0] != '/' && core_pattern[0] != '|') {
2819 "Unsafe core_pattern used with fs.suid_dumpable=2.\n"
2820 "Pipe handler or fully qualified core dump path required.\n"
2821 "Set kernel.core_pattern before fs.suid_dumpable.\n"
2827 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2828 void __user *buffer, size_t *lenp, loff_t *ppos)
2830 int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2832 validate_coredump_safety();
2836 #ifdef CONFIG_COREDUMP
2837 static int proc_dostring_coredump(struct ctl_table *table, int write,
2838 void __user *buffer, size_t *lenp, loff_t *ppos)
2840 int error = proc_dostring(table, write, buffer, lenp, ppos);
2842 validate_coredump_safety();
2847 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2848 void __user *buffer,
2849 size_t *lenp, loff_t *ppos,
2850 unsigned long convmul,
2851 unsigned long convdiv)
2853 unsigned long *i, *min, *max;
2854 int vleft, first = 1, err = 0;
2856 char *kbuf = NULL, *p;
2858 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2863 i = (unsigned long *) data;
2864 min = (unsigned long *) table->extra1;
2865 max = (unsigned long *) table->extra2;
2866 vleft = table->maxlen / sizeof(unsigned long);
2870 if (proc_first_pos_non_zero_ignore(ppos, table))
2873 if (left > PAGE_SIZE - 1)
2874 left = PAGE_SIZE - 1;
2875 p = kbuf = memdup_user_nul(buffer, left);
2877 return PTR_ERR(kbuf);
2880 for (; left && vleft--; i++, first = 0) {
2886 left -= proc_skip_spaces(&p);
2890 err = proc_get_long(&p, &left, &val, &neg,
2892 sizeof(proc_wspace_sep), NULL);
2897 val = convmul * val / convdiv;
2898 if ((min && val < *min) || (max && val > *max)) {
2904 val = convdiv * (*i) / convmul;
2906 err = proc_put_char(&buffer, &left, '\t');
2910 err = proc_put_long(&buffer, &left, val, false);
2916 if (!write && !first && left && !err)
2917 err = proc_put_char(&buffer, &left, '\n');
2919 left -= proc_skip_spaces(&p);
2923 return err ? : -EINVAL;
2931 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2932 void __user *buffer,
2933 size_t *lenp, loff_t *ppos,
2934 unsigned long convmul,
2935 unsigned long convdiv)
2937 return __do_proc_doulongvec_minmax(table->data, table, write,
2938 buffer, lenp, ppos, convmul, convdiv);
2942 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2943 * @table: the sysctl table
2944 * @write: %TRUE if this is a write to the sysctl file
2945 * @buffer: the user buffer
2946 * @lenp: the size of the user buffer
2947 * @ppos: file position
2949 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2950 * values from/to the user buffer, treated as an ASCII string.
2952 * This routine will ensure the values are within the range specified by
2953 * table->extra1 (min) and table->extra2 (max).
2955 * Returns 0 on success.
2957 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2958 void __user *buffer, size_t *lenp, loff_t *ppos)
2960 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2964 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2965 * @table: the sysctl table
2966 * @write: %TRUE if this is a write to the sysctl file
2967 * @buffer: the user buffer
2968 * @lenp: the size of the user buffer
2969 * @ppos: file position
2971 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2972 * values from/to the user buffer, treated as an ASCII string. The values
2973 * are treated as milliseconds, and converted to jiffies when they are stored.
2975 * This routine will ensure the values are within the range specified by
2976 * table->extra1 (min) and table->extra2 (max).
2978 * Returns 0 on success.
2980 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2981 void __user *buffer,
2982 size_t *lenp, loff_t *ppos)
2984 return do_proc_doulongvec_minmax(table, write, buffer,
2985 lenp, ppos, HZ, 1000l);
2989 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2991 int write, void *data)
2994 if (*lvalp > INT_MAX / HZ)
2996 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
3002 lval = -(unsigned long)val;
3005 lval = (unsigned long)val;
3012 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
3014 int write, void *data)
3017 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
3019 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
3025 lval = -(unsigned long)val;
3028 lval = (unsigned long)val;
3030 *lvalp = jiffies_to_clock_t(lval);
3035 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
3037 int write, void *data)
3040 unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
3050 lval = -(unsigned long)val;
3053 lval = (unsigned long)val;
3055 *lvalp = jiffies_to_msecs(lval);
3061 * proc_dointvec_jiffies - read a vector of integers as seconds
3062 * @table: the sysctl table
3063 * @write: %TRUE if this is a write to the sysctl file
3064 * @buffer: the user buffer
3065 * @lenp: the size of the user buffer
3066 * @ppos: file position
3068 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
3069 * values from/to the user buffer, treated as an ASCII string.
3070 * The values read are assumed to be in seconds, and are converted into
3073 * Returns 0 on success.
3075 int proc_dointvec_jiffies(struct ctl_table *table, int write,
3076 void __user *buffer, size_t *lenp, loff_t *ppos)
3078 return do_proc_dointvec(table,write,buffer,lenp,ppos,
3079 do_proc_dointvec_jiffies_conv,NULL);
3083 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
3084 * @table: the sysctl table
3085 * @write: %TRUE if this is a write to the sysctl file
3086 * @buffer: the user buffer
3087 * @lenp: the size of the user buffer
3088 * @ppos: pointer to the file position
3090 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
3091 * values from/to the user buffer, treated as an ASCII string.
3092 * The values read are assumed to be in 1/USER_HZ seconds, and
3093 * are converted into jiffies.
3095 * Returns 0 on success.
3097 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
3098 void __user *buffer, size_t *lenp, loff_t *ppos)
3100 return do_proc_dointvec(table,write,buffer,lenp,ppos,
3101 do_proc_dointvec_userhz_jiffies_conv,NULL);
3105 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
3106 * @table: the sysctl table
3107 * @write: %TRUE if this is a write to the sysctl file
3108 * @buffer: the user buffer
3109 * @lenp: the size of the user buffer
3110 * @ppos: file position
3111 * @ppos: the current position in the file
3113 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
3114 * values from/to the user buffer, treated as an ASCII string.
3115 * The values read are assumed to be in 1/1000 seconds, and
3116 * are converted into jiffies.
3118 * Returns 0 on success.
3120 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
3121 void __user *buffer, size_t *lenp, loff_t *ppos)
3123 return do_proc_dointvec(table, write, buffer, lenp, ppos,
3124 do_proc_dointvec_ms_jiffies_conv, NULL);
3127 static int proc_do_cad_pid(struct ctl_table *table, int write,
3128 void __user *buffer, size_t *lenp, loff_t *ppos)
3130 struct pid *new_pid;
3134 tmp = pid_vnr(cad_pid);
3136 r = __do_proc_dointvec(&tmp, table, write, buffer,
3137 lenp, ppos, NULL, NULL);
3141 new_pid = find_get_pid(tmp);
3145 put_pid(xchg(&cad_pid, new_pid));
3150 * proc_do_large_bitmap - read/write from/to a large bitmap
3151 * @table: the sysctl table
3152 * @write: %TRUE if this is a write to the sysctl file
3153 * @buffer: the user buffer
3154 * @lenp: the size of the user buffer
3155 * @ppos: file position
3157 * The bitmap is stored at table->data and the bitmap length (in bits)
3160 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
3161 * large bitmaps may be represented in a compact manner. Writing into
3162 * the file will clear the bitmap then update it with the given input.
3164 * Returns 0 on success.
3166 int proc_do_large_bitmap(struct ctl_table *table, int write,
3167 void __user *buffer, size_t *lenp, loff_t *ppos)
3171 size_t left = *lenp;
3172 unsigned long bitmap_len = table->maxlen;
3173 unsigned long *bitmap = *(unsigned long **) table->data;
3174 unsigned long *tmp_bitmap = NULL;
3175 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
3177 if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
3186 if (left > PAGE_SIZE - 1) {
3187 left = PAGE_SIZE - 1;
3188 /* How much of the buffer we'll skip this pass */
3189 skipped = *lenp - left;
3192 p = kbuf = memdup_user_nul(buffer, left);
3194 return PTR_ERR(kbuf);
3196 tmp_bitmap = bitmap_zalloc(bitmap_len, GFP_KERNEL);
3201 proc_skip_char(&p, &left, '\n');
3202 while (!err && left) {
3203 unsigned long val_a, val_b;
3207 /* In case we stop parsing mid-number, we can reset */
3209 err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
3212 * If we consumed the entirety of a truncated buffer or
3213 * only one char is left (may be a "-"), then stop here,
3214 * reset, & come back for more.
3216 if ((left <= 1) && skipped) {
3223 if (val_a >= bitmap_len || neg) {
3235 err = proc_get_long(&p, &left, &val_b,
3236 &neg, tr_b, sizeof(tr_b),
3239 * If we consumed all of a truncated buffer or
3240 * then stop here, reset, & come back for more.
3242 if (!left && skipped) {
3249 if (val_b >= bitmap_len || neg ||
3260 bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
3262 proc_skip_char(&p, &left, '\n');
3267 unsigned long bit_a, bit_b = 0;
3270 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
3271 if (bit_a >= bitmap_len)
3273 bit_b = find_next_zero_bit(bitmap, bitmap_len,
3277 err = proc_put_char(&buffer, &left, ',');
3281 err = proc_put_long(&buffer, &left, bit_a, false);
3284 if (bit_a != bit_b) {
3285 err = proc_put_char(&buffer, &left, '-');
3288 err = proc_put_long(&buffer, &left, bit_b, false);
3296 err = proc_put_char(&buffer, &left, '\n');
3302 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
3304 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
3310 bitmap_free(tmp_bitmap);
3314 #else /* CONFIG_PROC_SYSCTL */
3316 int proc_dostring(struct ctl_table *table, int write,
3317 void __user *buffer, size_t *lenp, loff_t *ppos)
3322 int proc_dointvec(struct ctl_table *table, int write,
3323 void __user *buffer, size_t *lenp, loff_t *ppos)
3328 int proc_douintvec(struct ctl_table *table, int write,
3329 void __user *buffer, size_t *lenp, loff_t *ppos)
3334 int proc_dointvec_minmax(struct ctl_table *table, int write,
3335 void __user *buffer, size_t *lenp, loff_t *ppos)
3340 int proc_douintvec_minmax(struct ctl_table *table, int write,
3341 void __user *buffer, size_t *lenp, loff_t *ppos)
3346 int proc_dointvec_jiffies(struct ctl_table *table, int write,
3347 void __user *buffer, size_t *lenp, loff_t *ppos)
3352 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
3353 void __user *buffer, size_t *lenp, loff_t *ppos)
3358 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
3359 void __user *buffer, size_t *lenp, loff_t *ppos)
3364 int proc_doulongvec_minmax(struct ctl_table *table, int write,
3365 void __user *buffer, size_t *lenp, loff_t *ppos)
3370 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
3371 void __user *buffer,
3372 size_t *lenp, loff_t *ppos)
3377 int proc_do_large_bitmap(struct ctl_table *table, int write,
3378 void __user *buffer, size_t *lenp, loff_t *ppos)
3383 #endif /* CONFIG_PROC_SYSCTL */
3385 #if defined(CONFIG_SYSCTL)
3386 int proc_do_static_key(struct ctl_table *table, int write,
3387 void __user *buffer, size_t *lenp,
3390 struct static_key *key = (struct static_key *)table->data;
3391 static DEFINE_MUTEX(static_key_mutex);
3393 struct ctl_table tmp = {
3395 .maxlen = sizeof(val),
3396 .mode = table->mode,
3397 .extra1 = SYSCTL_ZERO,
3398 .extra2 = SYSCTL_ONE,
3401 if (write && !capable(CAP_SYS_ADMIN))
3404 mutex_lock(&static_key_mutex);
3405 val = static_key_enabled(key);
3406 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
3407 if (write && !ret) {
3409 static_key_enable(key);
3411 static_key_disable(key);
3413 mutex_unlock(&static_key_mutex);
3418 * No sense putting this after each symbol definition, twice,
3419 * exception granted :-)
3421 EXPORT_SYMBOL(proc_dointvec);
3422 EXPORT_SYMBOL(proc_douintvec);
3423 EXPORT_SYMBOL(proc_dointvec_jiffies);
3424 EXPORT_SYMBOL(proc_dointvec_minmax);
3425 EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
3426 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3427 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3428 EXPORT_SYMBOL(proc_dostring);
3429 EXPORT_SYMBOL(proc_doulongvec_minmax);
3430 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3431 EXPORT_SYMBOL(proc_do_large_bitmap);