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>
23 #include <linux/swap.h>
24 #include <linux/slab.h>
25 #include <linux/sysctl.h>
26 #include <linux/proc_fs.h>
27 #include <linux/capability.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/capability.h>
31 #include <linux/smp_lock.h>
32 #include <linux/init.h>
33 #include <linux/kernel.h>
34 #include <linux/kobject.h>
35 #include <linux/net.h>
36 #include <linux/sysrq.h>
37 #include <linux/highuid.h>
38 #include <linux/writeback.h>
39 #include <linux/hugetlb.h>
40 #include <linux/security.h>
41 #include <linux/initrd.h>
42 #include <linux/times.h>
43 #include <linux/limits.h>
44 #include <linux/dcache.h>
45 #include <linux/syscalls.h>
46 #include <linux/nfs_fs.h>
47 #include <linux/acpi.h>
49 #include <asm/uaccess.h>
50 #include <asm/processor.h>
52 extern int proc_nr_files(ctl_table
*table
, int write
, struct file
*filp
,
53 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
57 #include <asm/stacktrace.h>
60 #if defined(CONFIG_SYSCTL)
62 /* External variables not in a header file. */
64 extern int sysctl_overcommit_memory
;
65 extern int sysctl_overcommit_ratio
;
66 extern int sysctl_panic_on_oom
;
67 extern int max_threads
;
68 extern int core_uses_pid
;
69 extern int suid_dumpable
;
70 extern char core_pattern
[];
72 extern int min_free_kbytes
;
73 extern int printk_ratelimit_jiffies
;
74 extern int printk_ratelimit_burst
;
75 extern int pid_max_min
, pid_max_max
;
76 extern int sysctl_drop_caches
;
77 extern int percpu_pagelist_fraction
;
78 extern int compat_log
;
80 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
81 static int maxolduid
= 65535;
83 static int min_percpu_pagelist_fract
= 8;
85 static int ngroups_max
= NGROUPS_MAX
;
88 extern char modprobe_path
[];
90 #ifdef CONFIG_CHR_DEV_SG
91 extern int sg_big_buff
;
95 extern char reboot_command
[];
96 extern int stop_a_enabled
;
97 extern int scons_pwroff
;
101 extern int pwrsw_enabled
;
102 extern int unaligned_enabled
;
106 #ifdef CONFIG_MATHEMU
107 extern int sysctl_ieee_emulation_warnings
;
109 extern int sysctl_userprocess_debug
;
110 extern int spin_retry
;
113 extern int sysctl_hz_timer
;
115 #ifdef CONFIG_BSD_PROCESS_ACCT
116 extern int acct_parm
[];
120 extern int no_unaligned_warning
;
123 #ifdef CONFIG_RT_MUTEXES
124 extern int max_lock_depth
;
127 #ifdef CONFIG_SYSCTL_SYSCALL
128 static int parse_table(int __user
*, int, void __user
*, size_t __user
*,
129 void __user
*, size_t, ctl_table
*);
133 #ifdef CONFIG_PROC_SYSCTL
134 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
135 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
136 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
137 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
);
140 static ctl_table root_table
[];
141 static struct ctl_table_header root_table_header
=
142 { root_table
, LIST_HEAD_INIT(root_table_header
.ctl_entry
) };
144 static ctl_table kern_table
[];
145 static ctl_table vm_table
[];
146 static ctl_table fs_table
[];
147 static ctl_table debug_table
[];
148 static ctl_table dev_table
[];
149 extern ctl_table random_table
[];
150 #ifdef CONFIG_UNIX98_PTYS
151 extern ctl_table pty_table
[];
153 #ifdef CONFIG_INOTIFY_USER
154 extern ctl_table inotify_table
[];
157 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
158 int sysctl_legacy_va_layout
;
162 /* /proc declarations: */
164 #ifdef CONFIG_PROC_SYSCTL
166 static ssize_t
proc_readsys(struct file
*, char __user
*, size_t, loff_t
*);
167 static ssize_t
proc_writesys(struct file
*, const char __user
*, size_t, loff_t
*);
168 static int proc_opensys(struct inode
*, struct file
*);
170 const struct file_operations proc_sys_file_operations
= {
171 .open
= proc_opensys
,
172 .read
= proc_readsys
,
173 .write
= proc_writesys
,
176 extern struct proc_dir_entry
*proc_sys_root
;
178 static void register_proc_table(ctl_table
*, struct proc_dir_entry
*, void *);
179 static void unregister_proc_table(ctl_table
*, struct proc_dir_entry
*);
182 /* The default sysctl tables: */
184 static ctl_table root_table
[] = {
186 .ctl_name
= CTL_KERN
,
187 .procname
= "kernel",
212 .ctl_name
= CTL_DEBUG
,
215 .child
= debug_table
,
227 static ctl_table kern_table
[] = {
229 .ctl_name
= KERN_PANIC
,
231 .data
= &panic_timeout
,
232 .maxlen
= sizeof(int),
234 .proc_handler
= &proc_dointvec
,
237 .ctl_name
= KERN_CORE_USES_PID
,
238 .procname
= "core_uses_pid",
239 .data
= &core_uses_pid
,
240 .maxlen
= sizeof(int),
242 .proc_handler
= &proc_dointvec
,
245 .ctl_name
= KERN_CORE_PATTERN
,
246 .procname
= "core_pattern",
247 .data
= core_pattern
,
250 .proc_handler
= &proc_dostring
,
251 .strategy
= &sysctl_string
,
253 #ifdef CONFIG_PROC_SYSCTL
255 .ctl_name
= KERN_TAINTED
,
256 .procname
= "tainted",
258 .maxlen
= sizeof(int),
260 .proc_handler
= &proc_dointvec_taint
,
264 .ctl_name
= KERN_CAP_BSET
,
265 .procname
= "cap-bound",
267 .maxlen
= sizeof(kernel_cap_t
),
269 .proc_handler
= &proc_dointvec_bset
,
271 #ifdef CONFIG_BLK_DEV_INITRD
273 .ctl_name
= KERN_REALROOTDEV
,
274 .procname
= "real-root-dev",
275 .data
= &real_root_dev
,
276 .maxlen
= sizeof(int),
278 .proc_handler
= &proc_dointvec
,
283 .ctl_name
= KERN_SPARC_REBOOT
,
284 .procname
= "reboot-cmd",
285 .data
= reboot_command
,
288 .proc_handler
= &proc_dostring
,
289 .strategy
= &sysctl_string
,
292 .ctl_name
= KERN_SPARC_STOP_A
,
293 .procname
= "stop-a",
294 .data
= &stop_a_enabled
,
295 .maxlen
= sizeof (int),
297 .proc_handler
= &proc_dointvec
,
300 .ctl_name
= KERN_SPARC_SCONS_PWROFF
,
301 .procname
= "scons-poweroff",
302 .data
= &scons_pwroff
,
303 .maxlen
= sizeof (int),
305 .proc_handler
= &proc_dointvec
,
310 .ctl_name
= KERN_HPPA_PWRSW
,
311 .procname
= "soft-power",
312 .data
= &pwrsw_enabled
,
313 .maxlen
= sizeof (int),
315 .proc_handler
= &proc_dointvec
,
318 .ctl_name
= KERN_HPPA_UNALIGNED
,
319 .procname
= "unaligned-trap",
320 .data
= &unaligned_enabled
,
321 .maxlen
= sizeof (int),
323 .proc_handler
= &proc_dointvec
,
327 .ctl_name
= KERN_CTLALTDEL
,
328 .procname
= "ctrl-alt-del",
330 .maxlen
= sizeof(int),
332 .proc_handler
= &proc_dointvec
,
335 .ctl_name
= KERN_PRINTK
,
336 .procname
= "printk",
337 .data
= &console_loglevel
,
338 .maxlen
= 4*sizeof(int),
340 .proc_handler
= &proc_dointvec
,
344 .ctl_name
= KERN_MODPROBE
,
345 .procname
= "modprobe",
346 .data
= &modprobe_path
,
347 .maxlen
= KMOD_PATH_LEN
,
349 .proc_handler
= &proc_dostring
,
350 .strategy
= &sysctl_string
,
353 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
355 .ctl_name
= KERN_HOTPLUG
,
356 .procname
= "hotplug",
357 .data
= &uevent_helper
,
358 .maxlen
= UEVENT_HELPER_PATH_LEN
,
360 .proc_handler
= &proc_dostring
,
361 .strategy
= &sysctl_string
,
364 #ifdef CONFIG_CHR_DEV_SG
366 .ctl_name
= KERN_SG_BIG_BUFF
,
367 .procname
= "sg-big-buff",
368 .data
= &sg_big_buff
,
369 .maxlen
= sizeof (int),
371 .proc_handler
= &proc_dointvec
,
374 #ifdef CONFIG_BSD_PROCESS_ACCT
376 .ctl_name
= KERN_ACCT
,
379 .maxlen
= 3*sizeof(int),
381 .proc_handler
= &proc_dointvec
,
384 #ifdef CONFIG_MAGIC_SYSRQ
386 .ctl_name
= KERN_SYSRQ
,
388 .data
= &__sysrq_enabled
,
389 .maxlen
= sizeof (int),
391 .proc_handler
= &proc_dointvec
,
394 #ifdef CONFIG_PROC_SYSCTL
396 .ctl_name
= KERN_CADPID
,
397 .procname
= "cad_pid",
399 .maxlen
= sizeof (int),
401 .proc_handler
= &proc_do_cad_pid
,
405 .ctl_name
= KERN_MAX_THREADS
,
406 .procname
= "threads-max",
407 .data
= &max_threads
,
408 .maxlen
= sizeof(int),
410 .proc_handler
= &proc_dointvec
,
413 .ctl_name
= KERN_RANDOM
,
414 .procname
= "random",
416 .child
= random_table
,
418 #ifdef CONFIG_UNIX98_PTYS
420 .ctl_name
= KERN_PTY
,
427 .ctl_name
= KERN_OVERFLOWUID
,
428 .procname
= "overflowuid",
429 .data
= &overflowuid
,
430 .maxlen
= sizeof(int),
432 .proc_handler
= &proc_dointvec_minmax
,
433 .strategy
= &sysctl_intvec
,
434 .extra1
= &minolduid
,
435 .extra2
= &maxolduid
,
438 .ctl_name
= KERN_OVERFLOWGID
,
439 .procname
= "overflowgid",
440 .data
= &overflowgid
,
441 .maxlen
= sizeof(int),
443 .proc_handler
= &proc_dointvec_minmax
,
444 .strategy
= &sysctl_intvec
,
445 .extra1
= &minolduid
,
446 .extra2
= &maxolduid
,
449 #ifdef CONFIG_MATHEMU
451 .ctl_name
= KERN_IEEE_EMULATION_WARNINGS
,
452 .procname
= "ieee_emulation_warnings",
453 .data
= &sysctl_ieee_emulation_warnings
,
454 .maxlen
= sizeof(int),
456 .proc_handler
= &proc_dointvec
,
459 #ifdef CONFIG_NO_IDLE_HZ
461 .ctl_name
= KERN_HZ_TIMER
,
462 .procname
= "hz_timer",
463 .data
= &sysctl_hz_timer
,
464 .maxlen
= sizeof(int),
466 .proc_handler
= &proc_dointvec
,
470 .ctl_name
= KERN_S390_USER_DEBUG_LOGGING
,
471 .procname
= "userprocess_debug",
472 .data
= &sysctl_userprocess_debug
,
473 .maxlen
= sizeof(int),
475 .proc_handler
= &proc_dointvec
,
479 .ctl_name
= KERN_PIDMAX
,
480 .procname
= "pid_max",
482 .maxlen
= sizeof (int),
484 .proc_handler
= &proc_dointvec_minmax
,
485 .strategy
= sysctl_intvec
,
486 .extra1
= &pid_max_min
,
487 .extra2
= &pid_max_max
,
490 .ctl_name
= KERN_PANIC_ON_OOPS
,
491 .procname
= "panic_on_oops",
492 .data
= &panic_on_oops
,
493 .maxlen
= sizeof(int),
495 .proc_handler
= &proc_dointvec
,
498 .ctl_name
= KERN_PRINTK_RATELIMIT
,
499 .procname
= "printk_ratelimit",
500 .data
= &printk_ratelimit_jiffies
,
501 .maxlen
= sizeof(int),
503 .proc_handler
= &proc_dointvec_jiffies
,
504 .strategy
= &sysctl_jiffies
,
507 .ctl_name
= KERN_PRINTK_RATELIMIT_BURST
,
508 .procname
= "printk_ratelimit_burst",
509 .data
= &printk_ratelimit_burst
,
510 .maxlen
= sizeof(int),
512 .proc_handler
= &proc_dointvec
,
515 .ctl_name
= KERN_NGROUPS_MAX
,
516 .procname
= "ngroups_max",
517 .data
= &ngroups_max
,
518 .maxlen
= sizeof (int),
520 .proc_handler
= &proc_dointvec
,
522 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
524 .ctl_name
= KERN_UNKNOWN_NMI_PANIC
,
525 .procname
= "unknown_nmi_panic",
526 .data
= &unknown_nmi_panic
,
527 .maxlen
= sizeof (int),
529 .proc_handler
= &proc_dointvec
,
532 .ctl_name
= KERN_NMI_WATCHDOG
,
533 .procname
= "nmi_watchdog",
534 .data
= &nmi_watchdog_enabled
,
535 .maxlen
= sizeof (int),
537 .proc_handler
= &proc_nmi_enabled
,
540 #if defined(CONFIG_X86)
542 .ctl_name
= KERN_PANIC_ON_NMI
,
543 .procname
= "panic_on_unrecovered_nmi",
544 .data
= &panic_on_unrecovered_nmi
,
545 .maxlen
= sizeof(int),
547 .proc_handler
= &proc_dointvec
,
550 .ctl_name
= KERN_BOOTLOADER_TYPE
,
551 .procname
= "bootloader_type",
552 .data
= &bootloader_type
,
553 .maxlen
= sizeof (int),
555 .proc_handler
= &proc_dointvec
,
558 .ctl_name
= CTL_UNNUMBERED
,
559 .procname
= "kstack_depth_to_print",
560 .data
= &kstack_depth_to_print
,
561 .maxlen
= sizeof(int),
563 .proc_handler
= &proc_dointvec
,
566 #if defined(CONFIG_MMU)
568 .ctl_name
= KERN_RANDOMIZE
,
569 .procname
= "randomize_va_space",
570 .data
= &randomize_va_space
,
571 .maxlen
= sizeof(int),
573 .proc_handler
= &proc_dointvec
,
576 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
578 .ctl_name
= KERN_SPIN_RETRY
,
579 .procname
= "spin_retry",
581 .maxlen
= sizeof (int),
583 .proc_handler
= &proc_dointvec
,
586 #ifdef CONFIG_ACPI_SLEEP
588 .ctl_name
= KERN_ACPI_VIDEO_FLAGS
,
589 .procname
= "acpi_video_flags",
590 .data
= &acpi_video_flags
,
591 .maxlen
= sizeof (unsigned long),
593 .proc_handler
= &proc_doulongvec_minmax
,
598 .ctl_name
= KERN_IA64_UNALIGNED
,
599 .procname
= "ignore-unaligned-usertrap",
600 .data
= &no_unaligned_warning
,
601 .maxlen
= sizeof (int),
603 .proc_handler
= &proc_dointvec
,
608 .ctl_name
= KERN_COMPAT_LOG
,
609 .procname
= "compat-log",
611 .maxlen
= sizeof (int),
613 .proc_handler
= &proc_dointvec
,
616 #ifdef CONFIG_RT_MUTEXES
618 .ctl_name
= KERN_MAX_LOCK_DEPTH
,
619 .procname
= "max_lock_depth",
620 .data
= &max_lock_depth
,
621 .maxlen
= sizeof(int),
623 .proc_handler
= &proc_dointvec
,
630 /* Constants for minimum and maximum testing in vm_table.
631 We use these as one-element integer vectors. */
633 static int one_hundred
= 100;
636 static ctl_table vm_table
[] = {
638 .ctl_name
= VM_OVERCOMMIT_MEMORY
,
639 .procname
= "overcommit_memory",
640 .data
= &sysctl_overcommit_memory
,
641 .maxlen
= sizeof(sysctl_overcommit_memory
),
643 .proc_handler
= &proc_dointvec
,
646 .ctl_name
= VM_PANIC_ON_OOM
,
647 .procname
= "panic_on_oom",
648 .data
= &sysctl_panic_on_oom
,
649 .maxlen
= sizeof(sysctl_panic_on_oom
),
651 .proc_handler
= &proc_dointvec
,
654 .ctl_name
= VM_OVERCOMMIT_RATIO
,
655 .procname
= "overcommit_ratio",
656 .data
= &sysctl_overcommit_ratio
,
657 .maxlen
= sizeof(sysctl_overcommit_ratio
),
659 .proc_handler
= &proc_dointvec
,
662 .ctl_name
= VM_PAGE_CLUSTER
,
663 .procname
= "page-cluster",
664 .data
= &page_cluster
,
665 .maxlen
= sizeof(int),
667 .proc_handler
= &proc_dointvec
,
670 .ctl_name
= VM_DIRTY_BACKGROUND
,
671 .procname
= "dirty_background_ratio",
672 .data
= &dirty_background_ratio
,
673 .maxlen
= sizeof(dirty_background_ratio
),
675 .proc_handler
= &proc_dointvec_minmax
,
676 .strategy
= &sysctl_intvec
,
678 .extra2
= &one_hundred
,
681 .ctl_name
= VM_DIRTY_RATIO
,
682 .procname
= "dirty_ratio",
683 .data
= &vm_dirty_ratio
,
684 .maxlen
= sizeof(vm_dirty_ratio
),
686 .proc_handler
= &proc_dointvec_minmax
,
687 .strategy
= &sysctl_intvec
,
689 .extra2
= &one_hundred
,
692 .ctl_name
= VM_DIRTY_WB_CS
,
693 .procname
= "dirty_writeback_centisecs",
694 .data
= &dirty_writeback_interval
,
695 .maxlen
= sizeof(dirty_writeback_interval
),
697 .proc_handler
= &dirty_writeback_centisecs_handler
,
700 .ctl_name
= VM_DIRTY_EXPIRE_CS
,
701 .procname
= "dirty_expire_centisecs",
702 .data
= &dirty_expire_interval
,
703 .maxlen
= sizeof(dirty_expire_interval
),
705 .proc_handler
= &proc_dointvec_userhz_jiffies
,
708 .ctl_name
= VM_NR_PDFLUSH_THREADS
,
709 .procname
= "nr_pdflush_threads",
710 .data
= &nr_pdflush_threads
,
711 .maxlen
= sizeof nr_pdflush_threads
,
712 .mode
= 0444 /* read-only*/,
713 .proc_handler
= &proc_dointvec
,
716 .ctl_name
= VM_SWAPPINESS
,
717 .procname
= "swappiness",
718 .data
= &vm_swappiness
,
719 .maxlen
= sizeof(vm_swappiness
),
721 .proc_handler
= &proc_dointvec_minmax
,
722 .strategy
= &sysctl_intvec
,
724 .extra2
= &one_hundred
,
726 #ifdef CONFIG_HUGETLB_PAGE
728 .ctl_name
= VM_HUGETLB_PAGES
,
729 .procname
= "nr_hugepages",
730 .data
= &max_huge_pages
,
731 .maxlen
= sizeof(unsigned long),
733 .proc_handler
= &hugetlb_sysctl_handler
,
734 .extra1
= (void *)&hugetlb_zero
,
735 .extra2
= (void *)&hugetlb_infinity
,
738 .ctl_name
= VM_HUGETLB_GROUP
,
739 .procname
= "hugetlb_shm_group",
740 .data
= &sysctl_hugetlb_shm_group
,
741 .maxlen
= sizeof(gid_t
),
743 .proc_handler
= &proc_dointvec
,
747 .ctl_name
= VM_LOWMEM_RESERVE_RATIO
,
748 .procname
= "lowmem_reserve_ratio",
749 .data
= &sysctl_lowmem_reserve_ratio
,
750 .maxlen
= sizeof(sysctl_lowmem_reserve_ratio
),
752 .proc_handler
= &lowmem_reserve_ratio_sysctl_handler
,
753 .strategy
= &sysctl_intvec
,
756 .ctl_name
= VM_DROP_PAGECACHE
,
757 .procname
= "drop_caches",
758 .data
= &sysctl_drop_caches
,
759 .maxlen
= sizeof(int),
761 .proc_handler
= drop_caches_sysctl_handler
,
762 .strategy
= &sysctl_intvec
,
765 .ctl_name
= VM_MIN_FREE_KBYTES
,
766 .procname
= "min_free_kbytes",
767 .data
= &min_free_kbytes
,
768 .maxlen
= sizeof(min_free_kbytes
),
770 .proc_handler
= &min_free_kbytes_sysctl_handler
,
771 .strategy
= &sysctl_intvec
,
775 .ctl_name
= VM_PERCPU_PAGELIST_FRACTION
,
776 .procname
= "percpu_pagelist_fraction",
777 .data
= &percpu_pagelist_fraction
,
778 .maxlen
= sizeof(percpu_pagelist_fraction
),
780 .proc_handler
= &percpu_pagelist_fraction_sysctl_handler
,
781 .strategy
= &sysctl_intvec
,
782 .extra1
= &min_percpu_pagelist_fract
,
786 .ctl_name
= VM_MAX_MAP_COUNT
,
787 .procname
= "max_map_count",
788 .data
= &sysctl_max_map_count
,
789 .maxlen
= sizeof(sysctl_max_map_count
),
791 .proc_handler
= &proc_dointvec
795 .ctl_name
= VM_LAPTOP_MODE
,
796 .procname
= "laptop_mode",
797 .data
= &laptop_mode
,
798 .maxlen
= sizeof(laptop_mode
),
800 .proc_handler
= &proc_dointvec_jiffies
,
801 .strategy
= &sysctl_jiffies
,
804 .ctl_name
= VM_BLOCK_DUMP
,
805 .procname
= "block_dump",
807 .maxlen
= sizeof(block_dump
),
809 .proc_handler
= &proc_dointvec
,
810 .strategy
= &sysctl_intvec
,
814 .ctl_name
= VM_VFS_CACHE_PRESSURE
,
815 .procname
= "vfs_cache_pressure",
816 .data
= &sysctl_vfs_cache_pressure
,
817 .maxlen
= sizeof(sysctl_vfs_cache_pressure
),
819 .proc_handler
= &proc_dointvec
,
820 .strategy
= &sysctl_intvec
,
823 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
825 .ctl_name
= VM_LEGACY_VA_LAYOUT
,
826 .procname
= "legacy_va_layout",
827 .data
= &sysctl_legacy_va_layout
,
828 .maxlen
= sizeof(sysctl_legacy_va_layout
),
830 .proc_handler
= &proc_dointvec
,
831 .strategy
= &sysctl_intvec
,
837 .ctl_name
= VM_ZONE_RECLAIM_MODE
,
838 .procname
= "zone_reclaim_mode",
839 .data
= &zone_reclaim_mode
,
840 .maxlen
= sizeof(zone_reclaim_mode
),
842 .proc_handler
= &proc_dointvec
,
843 .strategy
= &sysctl_intvec
,
847 .ctl_name
= VM_MIN_UNMAPPED
,
848 .procname
= "min_unmapped_ratio",
849 .data
= &sysctl_min_unmapped_ratio
,
850 .maxlen
= sizeof(sysctl_min_unmapped_ratio
),
852 .proc_handler
= &sysctl_min_unmapped_ratio_sysctl_handler
,
853 .strategy
= &sysctl_intvec
,
855 .extra2
= &one_hundred
,
858 .ctl_name
= VM_MIN_SLAB
,
859 .procname
= "min_slab_ratio",
860 .data
= &sysctl_min_slab_ratio
,
861 .maxlen
= sizeof(sysctl_min_slab_ratio
),
863 .proc_handler
= &sysctl_min_slab_ratio_sysctl_handler
,
864 .strategy
= &sysctl_intvec
,
866 .extra2
= &one_hundred
,
871 .ctl_name
= VM_VDSO_ENABLED
,
872 .procname
= "vdso_enabled",
873 .data
= &vdso_enabled
,
874 .maxlen
= sizeof(vdso_enabled
),
876 .proc_handler
= &proc_dointvec
,
877 .strategy
= &sysctl_intvec
,
884 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
885 static ctl_table binfmt_misc_table
[] = {
890 static ctl_table fs_table
[] = {
892 .ctl_name
= FS_NRINODE
,
893 .procname
= "inode-nr",
894 .data
= &inodes_stat
,
895 .maxlen
= 2*sizeof(int),
897 .proc_handler
= &proc_dointvec
,
900 .ctl_name
= FS_STATINODE
,
901 .procname
= "inode-state",
902 .data
= &inodes_stat
,
903 .maxlen
= 7*sizeof(int),
905 .proc_handler
= &proc_dointvec
,
908 .ctl_name
= FS_NRFILE
,
909 .procname
= "file-nr",
911 .maxlen
= 3*sizeof(int),
913 .proc_handler
= &proc_nr_files
,
916 .ctl_name
= FS_MAXFILE
,
917 .procname
= "file-max",
918 .data
= &files_stat
.max_files
,
919 .maxlen
= sizeof(int),
921 .proc_handler
= &proc_dointvec
,
924 .ctl_name
= FS_DENTRY
,
925 .procname
= "dentry-state",
926 .data
= &dentry_stat
,
927 .maxlen
= 6*sizeof(int),
929 .proc_handler
= &proc_dointvec
,
932 .ctl_name
= FS_OVERFLOWUID
,
933 .procname
= "overflowuid",
934 .data
= &fs_overflowuid
,
935 .maxlen
= sizeof(int),
937 .proc_handler
= &proc_dointvec_minmax
,
938 .strategy
= &sysctl_intvec
,
939 .extra1
= &minolduid
,
940 .extra2
= &maxolduid
,
943 .ctl_name
= FS_OVERFLOWGID
,
944 .procname
= "overflowgid",
945 .data
= &fs_overflowgid
,
946 .maxlen
= sizeof(int),
948 .proc_handler
= &proc_dointvec_minmax
,
949 .strategy
= &sysctl_intvec
,
950 .extra1
= &minolduid
,
951 .extra2
= &maxolduid
,
954 .ctl_name
= FS_LEASES
,
955 .procname
= "leases-enable",
956 .data
= &leases_enable
,
957 .maxlen
= sizeof(int),
959 .proc_handler
= &proc_dointvec
,
961 #ifdef CONFIG_DNOTIFY
963 .ctl_name
= FS_DIR_NOTIFY
,
964 .procname
= "dir-notify-enable",
965 .data
= &dir_notify_enable
,
966 .maxlen
= sizeof(int),
968 .proc_handler
= &proc_dointvec
,
973 .ctl_name
= FS_LEASE_TIME
,
974 .procname
= "lease-break-time",
975 .data
= &lease_break_time
,
976 .maxlen
= sizeof(int),
978 .proc_handler
= &proc_dointvec
,
981 .ctl_name
= FS_AIO_NR
,
982 .procname
= "aio-nr",
984 .maxlen
= sizeof(aio_nr
),
986 .proc_handler
= &proc_doulongvec_minmax
,
989 .ctl_name
= FS_AIO_MAX_NR
,
990 .procname
= "aio-max-nr",
992 .maxlen
= sizeof(aio_max_nr
),
994 .proc_handler
= &proc_doulongvec_minmax
,
996 #ifdef CONFIG_INOTIFY_USER
998 .ctl_name
= FS_INOTIFY
,
999 .procname
= "inotify",
1001 .child
= inotify_table
,
1006 .ctl_name
= KERN_SETUID_DUMPABLE
,
1007 .procname
= "suid_dumpable",
1008 .data
= &suid_dumpable
,
1009 .maxlen
= sizeof(int),
1011 .proc_handler
= &proc_dointvec
,
1013 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1015 .ctl_name
= CTL_UNNUMBERED
,
1016 .procname
= "binfmt_misc",
1018 .child
= binfmt_misc_table
,
1024 static ctl_table debug_table
[] = {
1028 static ctl_table dev_table
[] = {
1032 static DEFINE_SPINLOCK(sysctl_lock
);
1034 /* called under sysctl_lock */
1035 static int use_table(struct ctl_table_header
*p
)
1037 if (unlikely(p
->unregistering
))
1043 /* called under sysctl_lock */
1044 static void unuse_table(struct ctl_table_header
*p
)
1047 if (unlikely(p
->unregistering
))
1048 complete(p
->unregistering
);
1051 /* called under sysctl_lock, will reacquire if has to wait */
1052 static void start_unregistering(struct ctl_table_header
*p
)
1055 * if p->used is 0, nobody will ever touch that entry again;
1056 * we'll eliminate all paths to it before dropping sysctl_lock
1058 if (unlikely(p
->used
)) {
1059 struct completion wait
;
1060 init_completion(&wait
);
1061 p
->unregistering
= &wait
;
1062 spin_unlock(&sysctl_lock
);
1063 wait_for_completion(&wait
);
1064 spin_lock(&sysctl_lock
);
1067 * do not remove from the list until nobody holds it; walking the
1068 * list in do_sysctl() relies on that.
1070 list_del_init(&p
->ctl_entry
);
1073 void sysctl_head_finish(struct ctl_table_header
*head
)
1077 spin_lock(&sysctl_lock
);
1079 spin_unlock(&sysctl_lock
);
1082 struct ctl_table_header
*sysctl_head_next(struct ctl_table_header
*prev
)
1084 struct ctl_table_header
*head
;
1085 struct list_head
*tmp
;
1086 spin_lock(&sysctl_lock
);
1088 tmp
= &prev
->ctl_entry
;
1092 tmp
= &root_table_header
.ctl_entry
;
1094 head
= list_entry(tmp
, struct ctl_table_header
, ctl_entry
);
1096 if (!use_table(head
))
1098 spin_unlock(&sysctl_lock
);
1102 if (tmp
== &root_table_header
.ctl_entry
)
1105 spin_unlock(&sysctl_lock
);
1109 void __init
sysctl_init(void)
1111 #ifdef CONFIG_PROC_SYSCTL
1112 register_proc_table(root_table
, proc_sys_root
, &root_table_header
);
1116 #ifdef CONFIG_SYSCTL_SYSCALL
1117 int do_sysctl(int __user
*name
, int nlen
, void __user
*oldval
, size_t __user
*oldlenp
,
1118 void __user
*newval
, size_t newlen
)
1120 struct ctl_table_header
*head
;
1121 int error
= -ENOTDIR
;
1123 if (nlen
<= 0 || nlen
>= CTL_MAXNAME
)
1127 if (!oldlenp
|| get_user(old_len
, oldlenp
))
1131 for (head
= sysctl_head_next(NULL
); head
;
1132 head
= sysctl_head_next(head
)) {
1133 error
= parse_table(name
, nlen
, oldval
, oldlenp
,
1134 newval
, newlen
, head
->ctl_table
);
1135 if (error
!= -ENOTDIR
) {
1136 sysctl_head_finish(head
);
1143 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
1145 struct __sysctl_args tmp
;
1148 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
1152 error
= do_sysctl(tmp
.name
, tmp
.nlen
, tmp
.oldval
, tmp
.oldlenp
,
1153 tmp
.newval
, tmp
.newlen
);
1157 #endif /* CONFIG_SYSCTL_SYSCALL */
1160 * ctl_perm does NOT grant the superuser all rights automatically, because
1161 * some sysctl variables are readonly even to root.
1164 static int test_perm(int mode
, int op
)
1168 else if (in_egroup_p(0))
1170 if ((mode
& op
& 0007) == op
)
1175 static inline int ctl_perm(ctl_table
*table
, int op
)
1178 error
= security_sysctl(table
, op
);
1181 return test_perm(table
->mode
, op
);
1184 #ifdef CONFIG_SYSCTL_SYSCALL
1185 static int parse_table(int __user
*name
, int nlen
,
1186 void __user
*oldval
, size_t __user
*oldlenp
,
1187 void __user
*newval
, size_t newlen
,
1194 if (get_user(n
, name
))
1196 for ( ; table
->ctl_name
|| table
->procname
; table
++) {
1197 if (!table
->ctl_name
)
1199 if (n
== table
->ctl_name
) {
1202 if (ctl_perm(table
, 001))
1206 table
= table
->child
;
1209 error
= do_sysctl_strategy(table
, name
, nlen
,
1218 /* Perform the actual read/write of a sysctl table entry. */
1219 int do_sysctl_strategy (ctl_table
*table
,
1220 int __user
*name
, int nlen
,
1221 void __user
*oldval
, size_t __user
*oldlenp
,
1222 void __user
*newval
, size_t newlen
)
1231 if (ctl_perm(table
, op
))
1234 if (table
->strategy
) {
1235 rc
= table
->strategy(table
, name
, nlen
, oldval
, oldlenp
,
1243 /* If there is no strategy routine, or if the strategy returns
1244 * zero, proceed with automatic r/w */
1245 if (table
->data
&& table
->maxlen
) {
1246 if (oldval
&& oldlenp
) {
1247 if (get_user(len
, oldlenp
))
1250 if (len
> table
->maxlen
)
1251 len
= table
->maxlen
;
1252 if(copy_to_user(oldval
, table
->data
, len
))
1254 if(put_user(len
, oldlenp
))
1258 if (newval
&& newlen
) {
1260 if (len
> table
->maxlen
)
1261 len
= table
->maxlen
;
1262 if(copy_from_user(table
->data
, newval
, len
))
1268 #endif /* CONFIG_SYSCTL_SYSCALL */
1271 * register_sysctl_table - register a sysctl hierarchy
1272 * @table: the top-level table structure
1274 * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1275 * array. An entry with a ctl_name of 0 terminates the table.
1277 * The members of the &ctl_table structure are used as follows:
1279 * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1280 * must be unique within that level of sysctl
1282 * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1283 * enter a sysctl file
1285 * data - a pointer to data for use by proc_handler
1287 * maxlen - the maximum size in bytes of the data
1289 * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1291 * child - a pointer to the child sysctl table if this entry is a directory, or
1294 * proc_handler - the text handler routine (described below)
1296 * strategy - the strategy routine (described below)
1298 * de - for internal use by the sysctl routines
1300 * extra1, extra2 - extra pointers usable by the proc handler routines
1302 * Leaf nodes in the sysctl tree will be represented by a single file
1303 * under /proc; non-leaf nodes will be represented by directories.
1305 * sysctl(2) can automatically manage read and write requests through
1306 * the sysctl table. The data and maxlen fields of the ctl_table
1307 * struct enable minimal validation of the values being written to be
1308 * performed, and the mode field allows minimal authentication.
1310 * More sophisticated management can be enabled by the provision of a
1311 * strategy routine with the table entry. This will be called before
1312 * any automatic read or write of the data is performed.
1314 * The strategy routine may return
1316 * < 0 - Error occurred (error is passed to user process)
1318 * 0 - OK - proceed with automatic read or write.
1320 * > 0 - OK - read or write has been done by the strategy routine, so
1321 * return immediately.
1323 * There must be a proc_handler routine for any terminal nodes
1324 * mirrored under /proc/sys (non-terminals are handled by a built-in
1325 * directory handler). Several default handlers are available to
1326 * cover common cases -
1328 * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1329 * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(),
1330 * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1332 * It is the handler's job to read the input buffer from user memory
1333 * and process it. The handler should return 0 on success.
1335 * This routine returns %NULL on a failure to register, and a pointer
1336 * to the table header on success.
1338 struct ctl_table_header
*register_sysctl_table(ctl_table
* table
)
1340 struct ctl_table_header
*tmp
;
1341 tmp
= kmalloc(sizeof(struct ctl_table_header
), GFP_KERNEL
);
1344 tmp
->ctl_table
= table
;
1345 INIT_LIST_HEAD(&tmp
->ctl_entry
);
1347 tmp
->unregistering
= NULL
;
1348 spin_lock(&sysctl_lock
);
1349 list_add_tail(&tmp
->ctl_entry
, &root_table_header
.ctl_entry
);
1350 spin_unlock(&sysctl_lock
);
1351 #ifdef CONFIG_PROC_SYSCTL
1352 register_proc_table(table
, proc_sys_root
, tmp
);
1358 * unregister_sysctl_table - unregister a sysctl table hierarchy
1359 * @header: the header returned from register_sysctl_table
1361 * Unregisters the sysctl table and all children. proc entries may not
1362 * actually be removed until they are no longer used by anyone.
1364 void unregister_sysctl_table(struct ctl_table_header
* header
)
1367 spin_lock(&sysctl_lock
);
1368 start_unregistering(header
);
1369 #ifdef CONFIG_PROC_SYSCTL
1370 unregister_proc_table(header
->ctl_table
, proc_sys_root
);
1372 spin_unlock(&sysctl_lock
);
1376 #else /* !CONFIG_SYSCTL */
1377 struct ctl_table_header
* register_sysctl_table(ctl_table
* table
,
1383 void unregister_sysctl_table(struct ctl_table_header
* table
)
1387 #endif /* CONFIG_SYSCTL */
1393 #ifdef CONFIG_PROC_SYSCTL
1395 /* Scan the sysctl entries in table and add them all into /proc */
1396 static void register_proc_table(ctl_table
* table
, struct proc_dir_entry
*root
, void *set
)
1398 struct proc_dir_entry
*de
;
1402 for (; table
->ctl_name
|| table
->procname
; table
++) {
1403 /* Can't do anything without a proc name. */
1404 if (!table
->procname
)
1406 /* Maybe we can't do anything with it... */
1407 if (!table
->proc_handler
&& !table
->child
) {
1408 printk(KERN_WARNING
"SYSCTL: Can't register %s\n",
1413 len
= strlen(table
->procname
);
1417 if (table
->proc_handler
)
1421 for (de
= root
->subdir
; de
; de
= de
->next
) {
1422 if (proc_match(len
, table
->procname
, de
))
1425 /* If the subdir exists already, de is non-NULL */
1429 de
= create_proc_entry(table
->procname
, mode
, root
);
1433 de
->data
= (void *) table
;
1434 if (table
->proc_handler
)
1435 de
->proc_fops
= &proc_sys_file_operations
;
1438 if (de
->mode
& S_IFDIR
)
1439 register_proc_table(table
->child
, de
, set
);
1444 * Unregister a /proc sysctl table and any subdirectories.
1446 static void unregister_proc_table(ctl_table
* table
, struct proc_dir_entry
*root
)
1448 struct proc_dir_entry
*de
;
1449 for (; table
->ctl_name
|| table
->procname
; table
++) {
1450 if (!(de
= table
->de
))
1452 if (de
->mode
& S_IFDIR
) {
1453 if (!table
->child
) {
1454 printk (KERN_ALERT
"Help - malformed sysctl tree on free\n");
1457 unregister_proc_table(table
->child
, de
);
1459 /* Don't unregister directories which still have entries.. */
1465 * In any case, mark the entry as goner; we'll keep it
1466 * around if it's busy, but we'll know to do nothing with
1467 * its fields. We are under sysctl_lock here.
1471 /* Don't unregister proc entries that are still being used.. */
1472 if (atomic_read(&de
->count
))
1476 remove_proc_entry(table
->procname
, root
);
1480 static ssize_t
do_rw_proc(int write
, struct file
* file
, char __user
* buf
,
1481 size_t count
, loff_t
*ppos
)
1484 struct proc_dir_entry
*de
= PDE(file
->f_path
.dentry
->d_inode
);
1485 struct ctl_table
*table
;
1487 ssize_t error
= -ENOTDIR
;
1489 spin_lock(&sysctl_lock
);
1490 if (de
&& de
->data
&& use_table(de
->set
)) {
1492 * at that point we know that sysctl was not unregistered
1493 * and won't be until we finish
1495 spin_unlock(&sysctl_lock
);
1496 table
= (struct ctl_table
*) de
->data
;
1497 if (!table
|| !table
->proc_handler
)
1500 op
= (write
? 002 : 004);
1501 if (ctl_perm(table
, op
))
1504 /* careful: calling conventions are nasty here */
1506 error
= (*table
->proc_handler
)(table
, write
, file
,
1511 spin_lock(&sysctl_lock
);
1512 unuse_table(de
->set
);
1514 spin_unlock(&sysctl_lock
);
1518 static int proc_opensys(struct inode
*inode
, struct file
*file
)
1520 if (file
->f_mode
& FMODE_WRITE
) {
1522 * sysctl entries that are not writable,
1523 * are _NOT_ writable, capabilities or not.
1525 if (!(inode
->i_mode
& S_IWUSR
))
1532 static ssize_t
proc_readsys(struct file
* file
, char __user
* buf
,
1533 size_t count
, loff_t
*ppos
)
1535 return do_rw_proc(0, file
, buf
, count
, ppos
);
1538 static ssize_t
proc_writesys(struct file
* file
, const char __user
* buf
,
1539 size_t count
, loff_t
*ppos
)
1541 return do_rw_proc(1, file
, (char __user
*) buf
, count
, ppos
);
1544 static int _proc_do_string(void* data
, int maxlen
, int write
,
1545 struct file
*filp
, void __user
*buffer
,
1546 size_t *lenp
, loff_t
*ppos
)
1552 if (!data
|| !maxlen
|| !*lenp
) {
1560 while (len
< *lenp
) {
1561 if (get_user(c
, p
++))
1563 if (c
== 0 || c
== '\n')
1569 if(copy_from_user(data
, buffer
, len
))
1571 ((char *) data
)[len
] = 0;
1589 if(copy_to_user(buffer
, data
, len
))
1592 if(put_user('\n', ((char __user
*) buffer
) + len
))
1603 * proc_dostring - read a string sysctl
1604 * @table: the sysctl table
1605 * @write: %TRUE if this is a write to the sysctl file
1606 * @filp: the file structure
1607 * @buffer: the user buffer
1608 * @lenp: the size of the user buffer
1609 * @ppos: file position
1611 * Reads/writes a string from/to the user buffer. If the kernel
1612 * buffer provided is not large enough to hold the string, the
1613 * string is truncated. The copied string is %NULL-terminated.
1614 * If the string is being read by the user process, it is copied
1615 * and a newline '\n' is added. It is truncated if the buffer is
1618 * Returns 0 on success.
1620 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
1621 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1623 return _proc_do_string(table
->data
, table
->maxlen
, write
, filp
,
1624 buffer
, lenp
, ppos
);
1628 static int do_proc_dointvec_conv(int *negp
, unsigned long *lvalp
,
1630 int write
, void *data
)
1633 *valp
= *negp
? -*lvalp
: *lvalp
;
1638 *lvalp
= (unsigned long)-val
;
1641 *lvalp
= (unsigned long)val
;
1647 static int __do_proc_dointvec(void *tbl_data
, ctl_table
*table
,
1648 int write
, struct file
*filp
, void __user
*buffer
,
1649 size_t *lenp
, loff_t
*ppos
,
1650 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1651 int write
, void *data
),
1654 #define TMPBUFLEN 21
1655 int *i
, vleft
, first
=1, neg
, val
;
1659 char buf
[TMPBUFLEN
], *p
;
1660 char __user
*s
= buffer
;
1662 if (!tbl_data
|| !table
->maxlen
|| !*lenp
||
1663 (*ppos
&& !write
)) {
1668 i
= (int *) tbl_data
;
1669 vleft
= table
->maxlen
/ sizeof(*i
);
1673 conv
= do_proc_dointvec_conv
;
1675 for (; left
&& vleft
--; i
++, first
=0) {
1690 if (len
> sizeof(buf
) - 1)
1691 len
= sizeof(buf
) - 1;
1692 if (copy_from_user(buf
, s
, len
))
1696 if (*p
== '-' && left
> 1) {
1700 if (*p
< '0' || *p
> '9')
1703 lval
= simple_strtoul(p
, &p
, 0);
1706 if ((len
< left
) && *p
&& !isspace(*p
))
1713 if (conv(&neg
, &lval
, i
, 1, data
))
1720 if (conv(&neg
, &lval
, i
, 0, data
))
1723 sprintf(p
, "%s%lu", neg
? "-" : "", lval
);
1727 if(copy_to_user(s
, buf
, len
))
1734 if (!write
&& !first
&& left
) {
1735 if(put_user('\n', s
))
1742 if (get_user(c
, s
++))
1757 static int do_proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1758 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
,
1759 int (*conv
)(int *negp
, unsigned long *lvalp
, int *valp
,
1760 int write
, void *data
),
1763 return __do_proc_dointvec(table
->data
, table
, write
, filp
,
1764 buffer
, lenp
, ppos
, conv
, data
);
1768 * proc_dointvec - read a vector of integers
1769 * @table: the sysctl table
1770 * @write: %TRUE if this is a write to the sysctl file
1771 * @filp: the file structure
1772 * @buffer: the user buffer
1773 * @lenp: the size of the user buffer
1774 * @ppos: file position
1776 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1777 * values from/to the user buffer, treated as an ASCII string.
1779 * Returns 0 on success.
1781 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
1782 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1784 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1792 static int do_proc_dointvec_bset_conv(int *negp
, unsigned long *lvalp
,
1794 int write
, void *data
)
1796 int op
= *(int *)data
;
1798 int val
= *negp
? -*lvalp
: *lvalp
;
1800 case OP_SET
: *valp
= val
; break;
1801 case OP_AND
: *valp
&= val
; break;
1802 case OP_OR
: *valp
|= val
; break;
1808 *lvalp
= (unsigned long)-val
;
1811 *lvalp
= (unsigned long)val
;
1818 * init may raise the set.
1821 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
1822 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1826 if (write
&& !capable(CAP_SYS_MODULE
)) {
1830 op
= is_init(current
) ? OP_SET
: OP_AND
;
1831 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1832 do_proc_dointvec_bset_conv
,&op
);
1836 * Taint values can only be increased
1838 static int proc_dointvec_taint(ctl_table
*table
, int write
, struct file
*filp
,
1839 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1843 if (!capable(CAP_SYS_ADMIN
))
1847 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
1848 do_proc_dointvec_bset_conv
,&op
);
1851 struct do_proc_dointvec_minmax_conv_param
{
1856 static int do_proc_dointvec_minmax_conv(int *negp
, unsigned long *lvalp
,
1858 int write
, void *data
)
1860 struct do_proc_dointvec_minmax_conv_param
*param
= data
;
1862 int val
= *negp
? -*lvalp
: *lvalp
;
1863 if ((param
->min
&& *param
->min
> val
) ||
1864 (param
->max
&& *param
->max
< val
))
1871 *lvalp
= (unsigned long)-val
;
1874 *lvalp
= (unsigned long)val
;
1881 * proc_dointvec_minmax - read a vector of integers with min/max values
1882 * @table: the sysctl table
1883 * @write: %TRUE if this is a write to the sysctl file
1884 * @filp: the file structure
1885 * @buffer: the user buffer
1886 * @lenp: the size of the user buffer
1887 * @ppos: file position
1889 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1890 * values from/to the user buffer, treated as an ASCII string.
1892 * This routine will ensure the values are within the range specified by
1893 * table->extra1 (min) and table->extra2 (max).
1895 * Returns 0 on success.
1897 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
1898 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
1900 struct do_proc_dointvec_minmax_conv_param param
= {
1901 .min
= (int *) table
->extra1
,
1902 .max
= (int *) table
->extra2
,
1904 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
1905 do_proc_dointvec_minmax_conv
, ¶m
);
1908 static int __do_proc_doulongvec_minmax(void *data
, ctl_table
*table
, int write
,
1910 void __user
*buffer
,
1911 size_t *lenp
, loff_t
*ppos
,
1912 unsigned long convmul
,
1913 unsigned long convdiv
)
1915 #define TMPBUFLEN 21
1916 unsigned long *i
, *min
, *max
, val
;
1917 int vleft
, first
=1, neg
;
1919 char buf
[TMPBUFLEN
], *p
;
1920 char __user
*s
= buffer
;
1922 if (!data
|| !table
->maxlen
|| !*lenp
||
1923 (*ppos
&& !write
)) {
1928 i
= (unsigned long *) data
;
1929 min
= (unsigned long *) table
->extra1
;
1930 max
= (unsigned long *) table
->extra2
;
1931 vleft
= table
->maxlen
/ sizeof(unsigned long);
1934 for (; left
&& vleft
--; i
++, min
++, max
++, first
=0) {
1949 if (len
> TMPBUFLEN
-1)
1951 if (copy_from_user(buf
, s
, len
))
1955 if (*p
== '-' && left
> 1) {
1959 if (*p
< '0' || *p
> '9')
1961 val
= simple_strtoul(p
, &p
, 0) * convmul
/ convdiv
;
1963 if ((len
< left
) && *p
&& !isspace(*p
))
1972 if ((min
&& val
< *min
) || (max
&& val
> *max
))
1979 sprintf(p
, "%lu", convdiv
* (*i
) / convmul
);
1983 if(copy_to_user(s
, buf
, len
))
1990 if (!write
&& !first
&& left
) {
1991 if(put_user('\n', s
))
1998 if (get_user(c
, s
++))
2013 static int do_proc_doulongvec_minmax(ctl_table
*table
, int write
,
2015 void __user
*buffer
,
2016 size_t *lenp
, loff_t
*ppos
,
2017 unsigned long convmul
,
2018 unsigned long convdiv
)
2020 return __do_proc_doulongvec_minmax(table
->data
, table
, write
,
2021 filp
, buffer
, lenp
, ppos
, convmul
, convdiv
);
2025 * proc_doulongvec_minmax - read a vector of long integers with min/max values
2026 * @table: the sysctl table
2027 * @write: %TRUE if this is a write to the sysctl file
2028 * @filp: the file structure
2029 * @buffer: the user buffer
2030 * @lenp: the size of the user buffer
2031 * @ppos: file position
2033 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2034 * values from/to the user buffer, treated as an ASCII string.
2036 * This routine will ensure the values are within the range specified by
2037 * table->extra1 (min) and table->extra2 (max).
2039 * Returns 0 on success.
2041 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2042 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2044 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
, lenp
, ppos
, 1l, 1l);
2048 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2049 * @table: the sysctl table
2050 * @write: %TRUE if this is a write to the sysctl file
2051 * @filp: the file structure
2052 * @buffer: the user buffer
2053 * @lenp: the size of the user buffer
2054 * @ppos: file position
2056 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2057 * values from/to the user buffer, treated as an ASCII string. The values
2058 * are treated as milliseconds, and converted to jiffies when they are stored.
2060 * This routine will ensure the values are within the range specified by
2061 * table->extra1 (min) and table->extra2 (max).
2063 * Returns 0 on success.
2065 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2067 void __user
*buffer
,
2068 size_t *lenp
, loff_t
*ppos
)
2070 return do_proc_doulongvec_minmax(table
, write
, filp
, buffer
,
2071 lenp
, ppos
, HZ
, 1000l);
2075 static int do_proc_dointvec_jiffies_conv(int *negp
, unsigned long *lvalp
,
2077 int write
, void *data
)
2080 if (*lvalp
> LONG_MAX
/ HZ
)
2082 *valp
= *negp
? -(*lvalp
*HZ
) : (*lvalp
*HZ
);
2088 lval
= (unsigned long)-val
;
2091 lval
= (unsigned long)val
;
2098 static int do_proc_dointvec_userhz_jiffies_conv(int *negp
, unsigned long *lvalp
,
2100 int write
, void *data
)
2103 if (USER_HZ
< HZ
&& *lvalp
> (LONG_MAX
/ HZ
) * USER_HZ
)
2105 *valp
= clock_t_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2111 lval
= (unsigned long)-val
;
2114 lval
= (unsigned long)val
;
2116 *lvalp
= jiffies_to_clock_t(lval
);
2121 static int do_proc_dointvec_ms_jiffies_conv(int *negp
, unsigned long *lvalp
,
2123 int write
, void *data
)
2126 *valp
= msecs_to_jiffies(*negp
? -*lvalp
: *lvalp
);
2132 lval
= (unsigned long)-val
;
2135 lval
= (unsigned long)val
;
2137 *lvalp
= jiffies_to_msecs(lval
);
2143 * proc_dointvec_jiffies - read a vector of integers as seconds
2144 * @table: the sysctl table
2145 * @write: %TRUE if this is a write to the sysctl file
2146 * @filp: the file structure
2147 * @buffer: the user buffer
2148 * @lenp: the size of the user buffer
2149 * @ppos: file position
2151 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2152 * values from/to the user buffer, treated as an ASCII string.
2153 * The values read are assumed to be in seconds, and are converted into
2156 * Returns 0 on success.
2158 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2159 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2161 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2162 do_proc_dointvec_jiffies_conv
,NULL
);
2166 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2167 * @table: the sysctl table
2168 * @write: %TRUE if this is a write to the sysctl file
2169 * @filp: the file structure
2170 * @buffer: the user buffer
2171 * @lenp: the size of the user buffer
2172 * @ppos: pointer to the file position
2174 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2175 * values from/to the user buffer, treated as an ASCII string.
2176 * The values read are assumed to be in 1/USER_HZ seconds, and
2177 * are converted into jiffies.
2179 * Returns 0 on success.
2181 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2182 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2184 return do_proc_dointvec(table
,write
,filp
,buffer
,lenp
,ppos
,
2185 do_proc_dointvec_userhz_jiffies_conv
,NULL
);
2189 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2190 * @table: the sysctl table
2191 * @write: %TRUE if this is a write to the sysctl file
2192 * @filp: the file structure
2193 * @buffer: the user buffer
2194 * @lenp: the size of the user buffer
2195 * @ppos: file position
2196 * @ppos: the current position in the file
2198 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2199 * values from/to the user buffer, treated as an ASCII string.
2200 * The values read are assumed to be in 1/1000 seconds, and
2201 * are converted into jiffies.
2203 * Returns 0 on success.
2205 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2206 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2208 return do_proc_dointvec(table
, write
, filp
, buffer
, lenp
, ppos
,
2209 do_proc_dointvec_ms_jiffies_conv
, NULL
);
2212 static int proc_do_cad_pid(ctl_table
*table
, int write
, struct file
*filp
,
2213 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2215 struct pid
*new_pid
;
2219 tmp
= pid_nr(cad_pid
);
2221 r
= __do_proc_dointvec(&tmp
, table
, write
, filp
, buffer
,
2222 lenp
, ppos
, NULL
, NULL
);
2226 new_pid
= find_get_pid(tmp
);
2230 put_pid(xchg(&cad_pid
, new_pid
));
2234 #else /* CONFIG_PROC_FS */
2236 int proc_dostring(ctl_table
*table
, int write
, struct file
*filp
,
2237 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2242 int proc_dointvec(ctl_table
*table
, int write
, struct file
*filp
,
2243 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2248 int proc_dointvec_bset(ctl_table
*table
, int write
, struct file
*filp
,
2249 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2254 int proc_dointvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2255 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2260 int proc_dointvec_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2261 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2266 int proc_dointvec_userhz_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2267 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2272 int proc_dointvec_ms_jiffies(ctl_table
*table
, int write
, struct file
*filp
,
2273 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2278 int proc_doulongvec_minmax(ctl_table
*table
, int write
, struct file
*filp
,
2279 void __user
*buffer
, size_t *lenp
, loff_t
*ppos
)
2284 int proc_doulongvec_ms_jiffies_minmax(ctl_table
*table
, int write
,
2286 void __user
*buffer
,
2287 size_t *lenp
, loff_t
*ppos
)
2293 #endif /* CONFIG_PROC_FS */
2296 #ifdef CONFIG_SYSCTL_SYSCALL
2298 * General sysctl support routines
2301 /* The generic string strategy routine: */
2302 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2303 void __user
*oldval
, size_t __user
*oldlenp
,
2304 void __user
*newval
, size_t newlen
)
2306 if (!table
->data
|| !table
->maxlen
)
2309 if (oldval
&& oldlenp
) {
2311 if (get_user(bufsize
, oldlenp
))
2314 size_t len
= strlen(table
->data
), copied
;
2316 /* This shouldn't trigger for a well-formed sysctl */
2317 if (len
> table
->maxlen
)
2318 len
= table
->maxlen
;
2320 /* Copy up to a max of bufsize-1 bytes of the string */
2321 copied
= (len
>= bufsize
) ? bufsize
- 1 : len
;
2323 if (copy_to_user(oldval
, table
->data
, copied
) ||
2324 put_user(0, (char __user
*)(oldval
+ copied
)))
2326 if (put_user(len
, oldlenp
))
2330 if (newval
&& newlen
) {
2331 size_t len
= newlen
;
2332 if (len
> table
->maxlen
)
2333 len
= table
->maxlen
;
2334 if(copy_from_user(table
->data
, newval
, len
))
2336 if (len
== table
->maxlen
)
2338 ((char *) table
->data
)[len
] = 0;
2344 * This function makes sure that all of the integers in the vector
2345 * are between the minimum and maximum values given in the arrays
2346 * table->extra1 and table->extra2, respectively.
2348 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2349 void __user
*oldval
, size_t __user
*oldlenp
,
2350 void __user
*newval
, size_t newlen
)
2353 if (newval
&& newlen
) {
2354 int __user
*vec
= (int __user
*) newval
;
2355 int *min
= (int *) table
->extra1
;
2356 int *max
= (int *) table
->extra2
;
2360 if (newlen
% sizeof(int) != 0)
2363 if (!table
->extra1
&& !table
->extra2
)
2366 if (newlen
> table
->maxlen
)
2367 newlen
= table
->maxlen
;
2368 length
= newlen
/ sizeof(int);
2370 for (i
= 0; i
< length
; i
++) {
2372 if (get_user(value
, vec
+ i
))
2374 if (min
&& value
< min
[i
])
2376 if (max
&& value
> max
[i
])
2383 /* Strategy function to convert jiffies to seconds */
2384 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2385 void __user
*oldval
, size_t __user
*oldlenp
,
2386 void __user
*newval
, size_t newlen
)
2388 if (oldval
&& oldlenp
) {
2391 if (get_user(olen
, oldlenp
))
2396 if (olen
< sizeof(int))
2399 val
= *(int *)(table
->data
) / HZ
;
2400 if (put_user(val
, (int __user
*)oldval
))
2402 if (put_user(sizeof(int), oldlenp
))
2406 if (newval
&& newlen
) {
2408 if (newlen
!= sizeof(int))
2410 if (get_user(new, (int __user
*)newval
))
2412 *(int *)(table
->data
) = new*HZ
;
2417 /* Strategy function to convert jiffies to seconds */
2418 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2419 void __user
*oldval
, size_t __user
*oldlenp
,
2420 void __user
*newval
, size_t newlen
)
2422 if (oldval
&& oldlenp
) {
2425 if (get_user(olen
, oldlenp
))
2430 if (olen
< sizeof(int))
2433 val
= jiffies_to_msecs(*(int *)(table
->data
));
2434 if (put_user(val
, (int __user
*)oldval
))
2436 if (put_user(sizeof(int), oldlenp
))
2440 if (newval
&& newlen
) {
2442 if (newlen
!= sizeof(int))
2444 if (get_user(new, (int __user
*)newval
))
2446 *(int *)(table
->data
) = msecs_to_jiffies(new);
2453 #else /* CONFIG_SYSCTL_SYSCALL */
2456 asmlinkage
long sys_sysctl(struct __sysctl_args __user
*args
)
2458 static int msg_count
;
2459 struct __sysctl_args tmp
;
2460 int name
[CTL_MAXNAME
];
2463 /* Read in the sysctl name for better debug message logging */
2464 if (copy_from_user(&tmp
, args
, sizeof(tmp
)))
2466 if (tmp
.nlen
<= 0 || tmp
.nlen
>= CTL_MAXNAME
)
2468 for (i
= 0; i
< tmp
.nlen
; i
++)
2469 if (get_user(name
[i
], tmp
.name
+ i
))
2472 /* Ignore accesses to kernel.version */
2473 if ((tmp
.nlen
== 2) && (name
[0] == CTL_KERN
) && (name
[1] == KERN_VERSION
))
2476 if (msg_count
< 5) {
2479 "warning: process `%s' used the removed sysctl "
2480 "system call with ", current
->comm
);
2481 for (i
= 0; i
< tmp
.nlen
; i
++)
2482 printk("%d.", name
[i
]);
2489 int sysctl_string(ctl_table
*table
, int __user
*name
, int nlen
,
2490 void __user
*oldval
, size_t __user
*oldlenp
,
2491 void __user
*newval
, size_t newlen
)
2496 int sysctl_intvec(ctl_table
*table
, int __user
*name
, int nlen
,
2497 void __user
*oldval
, size_t __user
*oldlenp
,
2498 void __user
*newval
, size_t newlen
)
2503 int sysctl_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2504 void __user
*oldval
, size_t __user
*oldlenp
,
2505 void __user
*newval
, size_t newlen
)
2510 int sysctl_ms_jiffies(ctl_table
*table
, int __user
*name
, int nlen
,
2511 void __user
*oldval
, size_t __user
*oldlenp
,
2512 void __user
*newval
, size_t newlen
)
2517 #endif /* CONFIG_SYSCTL_SYSCALL */
2520 * No sense putting this after each symbol definition, twice,
2521 * exception granted :-)
2523 EXPORT_SYMBOL(proc_dointvec
);
2524 EXPORT_SYMBOL(proc_dointvec_jiffies
);
2525 EXPORT_SYMBOL(proc_dointvec_minmax
);
2526 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies
);
2527 EXPORT_SYMBOL(proc_dointvec_ms_jiffies
);
2528 EXPORT_SYMBOL(proc_dostring
);
2529 EXPORT_SYMBOL(proc_doulongvec_minmax
);
2530 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax
);
2531 EXPORT_SYMBOL(register_sysctl_table
);
2532 EXPORT_SYMBOL(sysctl_intvec
);
2533 EXPORT_SYMBOL(sysctl_jiffies
);
2534 EXPORT_SYMBOL(sysctl_ms_jiffies
);
2535 EXPORT_SYMBOL(sysctl_string
);
2536 EXPORT_SYMBOL(unregister_sysctl_table
);