V3 file capabilities: alter behavior of cap_setpcap
[linux-2.6.git] / kernel / sysctl.c
1 /*
2  * sysctl.c: General linux system control interface
3  *
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
12  *  Horn.
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
16  *  Wendling.
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
19  */
20
21 #include <linux/module.h>
22 #include <linux/mm.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/security.h>
28 #include <linux/ctype.h>
29 #include <linux/utsname.h>
30 #include <linux/smp_lock.h>
31 #include <linux/fs.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>
48 #include <linux/reboot.h>
49
50 #include <asm/uaccess.h>
51 #include <asm/processor.h>
52
53 #ifdef CONFIG_X86
54 #include <asm/nmi.h>
55 #include <asm/stacktrace.h>
56 #endif
57
58 static int deprecated_sysctl_warning(struct __sysctl_args *args);
59
60 #if defined(CONFIG_SYSCTL)
61
62 /* External variables not in a header file. */
63 extern int C_A_D;
64 extern int print_fatal_signals;
65 extern int sysctl_overcommit_memory;
66 extern int sysctl_overcommit_ratio;
67 extern int sysctl_panic_on_oom;
68 extern int sysctl_oom_kill_allocating_task;
69 extern int max_threads;
70 extern int core_uses_pid;
71 extern int suid_dumpable;
72 extern char core_pattern[];
73 extern int pid_max;
74 extern int min_free_kbytes;
75 extern int printk_ratelimit_jiffies;
76 extern int printk_ratelimit_burst;
77 extern int pid_max_min, pid_max_max;
78 extern int sysctl_drop_caches;
79 extern int percpu_pagelist_fraction;
80 extern int compat_log;
81 extern int maps_protect;
82 extern int sysctl_stat_interval;
83 extern int audit_argv_kb;
84
85 /* Constants used for minimum and  maximum */
86 #ifdef CONFIG_DETECT_SOFTLOCKUP
87 static int one = 1;
88 static int sixty = 60;
89 #endif
90
91 #ifdef CONFIG_MMU
92 static int two = 2;
93 #endif
94
95 static int zero;
96 static int one_hundred = 100;
97
98 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
99 static int maxolduid = 65535;
100 static int minolduid;
101 static int min_percpu_pagelist_fract = 8;
102
103 static int ngroups_max = NGROUPS_MAX;
104
105 #ifdef CONFIG_KMOD
106 extern char modprobe_path[];
107 #endif
108 #ifdef CONFIG_CHR_DEV_SG
109 extern int sg_big_buff;
110 #endif
111
112 #ifdef __sparc__
113 extern char reboot_command [];
114 extern int stop_a_enabled;
115 extern int scons_pwroff;
116 #endif
117
118 #ifdef __hppa__
119 extern int pwrsw_enabled;
120 extern int unaligned_enabled;
121 #endif
122
123 #ifdef CONFIG_S390
124 #ifdef CONFIG_MATHEMU
125 extern int sysctl_ieee_emulation_warnings;
126 #endif
127 extern int sysctl_userprocess_debug;
128 extern int spin_retry;
129 #endif
130
131 extern int sysctl_hz_timer;
132
133 #ifdef CONFIG_BSD_PROCESS_ACCT
134 extern int acct_parm[];
135 #endif
136
137 #ifdef CONFIG_IA64
138 extern int no_unaligned_warning;
139 #endif
140
141 #ifdef CONFIG_RT_MUTEXES
142 extern int max_lock_depth;
143 #endif
144
145 #ifdef CONFIG_SYSCTL_SYSCALL
146 static int parse_table(int __user *, int, void __user *, size_t __user *,
147                 void __user *, size_t, struct ctl_table *);
148 #endif
149
150
151 #ifdef CONFIG_PROC_SYSCTL
152 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
153                   void __user *buffer, size_t *lenp, loff_t *ppos);
154 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
155                                void __user *buffer, size_t *lenp, loff_t *ppos);
156 #endif
157
158 static struct ctl_table root_table[];
159 static struct ctl_table_header root_table_header =
160         { root_table, LIST_HEAD_INIT(root_table_header.ctl_entry) };
161
162 static struct ctl_table kern_table[];
163 static struct ctl_table vm_table[];
164 static struct ctl_table fs_table[];
165 static struct ctl_table debug_table[];
166 static struct ctl_table dev_table[];
167 extern struct ctl_table random_table[];
168 #ifdef CONFIG_INOTIFY_USER
169 extern struct ctl_table inotify_table[];
170 #endif
171
172 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
173 int sysctl_legacy_va_layout;
174 #endif
175
176 extern int prove_locking;
177 extern int lock_stat;
178
179 /* The default sysctl tables: */
180
181 static struct ctl_table root_table[] = {
182         {
183                 .ctl_name       = CTL_KERN,
184                 .procname       = "kernel",
185                 .mode           = 0555,
186                 .child          = kern_table,
187         },
188         {
189                 .ctl_name       = CTL_VM,
190                 .procname       = "vm",
191                 .mode           = 0555,
192                 .child          = vm_table,
193         },
194 #ifdef CONFIG_NET
195         {
196                 .ctl_name       = CTL_NET,
197                 .procname       = "net",
198                 .mode           = 0555,
199                 .child          = net_table,
200         },
201 #endif
202         {
203                 .ctl_name       = CTL_FS,
204                 .procname       = "fs",
205                 .mode           = 0555,
206                 .child          = fs_table,
207         },
208         {
209                 .ctl_name       = CTL_DEBUG,
210                 .procname       = "debug",
211                 .mode           = 0555,
212                 .child          = debug_table,
213         },
214         {
215                 .ctl_name       = CTL_DEV,
216                 .procname       = "dev",
217                 .mode           = 0555,
218                 .child          = dev_table,
219         },
220 /*
221  * NOTE: do not add new entries to this table unless you have read
222  * Documentation/sysctl/ctl_unnumbered.txt
223  */
224         { .ctl_name = 0 }
225 };
226
227 #ifdef CONFIG_SCHED_DEBUG
228 static unsigned long min_sched_granularity_ns = 100000;         /* 100 usecs */
229 static unsigned long max_sched_granularity_ns = 1000000000;     /* 1 second */
230 static unsigned long min_wakeup_granularity_ns;                 /* 0 usecs */
231 static unsigned long max_wakeup_granularity_ns = 1000000000;    /* 1 second */
232 #endif
233
234 static struct ctl_table kern_table[] = {
235 #ifdef CONFIG_SCHED_DEBUG
236         {
237                 .ctl_name       = CTL_UNNUMBERED,
238                 .procname       = "sched_nr_latency",
239                 .data           = &sysctl_sched_nr_latency,
240                 .maxlen         = sizeof(unsigned int),
241                 .mode           = 0644,
242                 .proc_handler   = &proc_dointvec,
243         },
244         {
245                 .ctl_name       = CTL_UNNUMBERED,
246                 .procname       = "sched_latency_ns",
247                 .data           = &sysctl_sched_latency,
248                 .maxlen         = sizeof(unsigned int),
249                 .mode           = 0644,
250                 .proc_handler   = &proc_dointvec_minmax,
251                 .strategy       = &sysctl_intvec,
252                 .extra1         = &min_sched_granularity_ns,
253                 .extra2         = &max_sched_granularity_ns,
254         },
255         {
256                 .ctl_name       = CTL_UNNUMBERED,
257                 .procname       = "sched_wakeup_granularity_ns",
258                 .data           = &sysctl_sched_wakeup_granularity,
259                 .maxlen         = sizeof(unsigned int),
260                 .mode           = 0644,
261                 .proc_handler   = &proc_dointvec_minmax,
262                 .strategy       = &sysctl_intvec,
263                 .extra1         = &min_wakeup_granularity_ns,
264                 .extra2         = &max_wakeup_granularity_ns,
265         },
266         {
267                 .ctl_name       = CTL_UNNUMBERED,
268                 .procname       = "sched_batch_wakeup_granularity_ns",
269                 .data           = &sysctl_sched_batch_wakeup_granularity,
270                 .maxlen         = sizeof(unsigned int),
271                 .mode           = 0644,
272                 .proc_handler   = &proc_dointvec_minmax,
273                 .strategy       = &sysctl_intvec,
274                 .extra1         = &min_wakeup_granularity_ns,
275                 .extra2         = &max_wakeup_granularity_ns,
276         },
277         {
278                 .ctl_name       = CTL_UNNUMBERED,
279                 .procname       = "sched_child_runs_first",
280                 .data           = &sysctl_sched_child_runs_first,
281                 .maxlen         = sizeof(unsigned int),
282                 .mode           = 0644,
283                 .proc_handler   = &proc_dointvec,
284         },
285         {
286                 .ctl_name       = CTL_UNNUMBERED,
287                 .procname       = "sched_features",
288                 .data           = &sysctl_sched_features,
289                 .maxlen         = sizeof(unsigned int),
290                 .mode           = 0644,
291                 .proc_handler   = &proc_dointvec,
292         },
293         {
294                 .ctl_name       = CTL_UNNUMBERED,
295                 .procname       = "sched_migration_cost",
296                 .data           = &sysctl_sched_migration_cost,
297                 .maxlen         = sizeof(unsigned int),
298                 .mode           = 0644,
299                 .proc_handler   = &proc_dointvec,
300         },
301 #endif
302         {
303                 .ctl_name       = CTL_UNNUMBERED,
304                 .procname       = "sched_compat_yield",
305                 .data           = &sysctl_sched_compat_yield,
306                 .maxlen         = sizeof(unsigned int),
307                 .mode           = 0644,
308                 .proc_handler   = &proc_dointvec,
309         },
310 #ifdef CONFIG_PROVE_LOCKING
311         {
312                 .ctl_name       = CTL_UNNUMBERED,
313                 .procname       = "prove_locking",
314                 .data           = &prove_locking,
315                 .maxlen         = sizeof(int),
316                 .mode           = 0644,
317                 .proc_handler   = &proc_dointvec,
318         },
319 #endif
320 #ifdef CONFIG_LOCK_STAT
321         {
322                 .ctl_name       = CTL_UNNUMBERED,
323                 .procname       = "lock_stat",
324                 .data           = &lock_stat,
325                 .maxlen         = sizeof(int),
326                 .mode           = 0644,
327                 .proc_handler   = &proc_dointvec,
328         },
329 #endif
330         {
331                 .ctl_name       = KERN_PANIC,
332                 .procname       = "panic",
333                 .data           = &panic_timeout,
334                 .maxlen         = sizeof(int),
335                 .mode           = 0644,
336                 .proc_handler   = &proc_dointvec,
337         },
338         {
339                 .ctl_name       = KERN_CORE_USES_PID,
340                 .procname       = "core_uses_pid",
341                 .data           = &core_uses_pid,
342                 .maxlen         = sizeof(int),
343                 .mode           = 0644,
344                 .proc_handler   = &proc_dointvec,
345         },
346 #ifdef CONFIG_AUDITSYSCALL
347         {
348                 .ctl_name       = CTL_UNNUMBERED,
349                 .procname       = "audit_argv_kb",
350                 .data           = &audit_argv_kb,
351                 .maxlen         = sizeof(int),
352                 .mode           = 0644,
353                 .proc_handler   = &proc_dointvec,
354         },
355 #endif
356         {
357                 .ctl_name       = KERN_CORE_PATTERN,
358                 .procname       = "core_pattern",
359                 .data           = core_pattern,
360                 .maxlen         = CORENAME_MAX_SIZE,
361                 .mode           = 0644,
362                 .proc_handler   = &proc_dostring,
363                 .strategy       = &sysctl_string,
364         },
365 #ifdef CONFIG_PROC_SYSCTL
366         {
367                 .procname       = "tainted",
368                 .data           = &tainted,
369                 .maxlen         = sizeof(int),
370                 .mode           = 0644,
371                 .proc_handler   = &proc_dointvec_taint,
372         },
373 #endif
374 #ifdef CONFIG_SECURITY_CAPABILITIES
375         {
376                 .procname       = "cap-bound",
377                 .data           = &cap_bset,
378                 .maxlen         = sizeof(kernel_cap_t),
379                 .mode           = 0600,
380                 .proc_handler   = &proc_dointvec_bset,
381         },
382 #endif /* def CONFIG_SECURITY_CAPABILITIES */
383 #ifdef CONFIG_BLK_DEV_INITRD
384         {
385                 .ctl_name       = KERN_REALROOTDEV,
386                 .procname       = "real-root-dev",
387                 .data           = &real_root_dev,
388                 .maxlen         = sizeof(int),
389                 .mode           = 0644,
390                 .proc_handler   = &proc_dointvec,
391         },
392 #endif
393         {
394                 .ctl_name       = CTL_UNNUMBERED,
395                 .procname       = "print-fatal-signals",
396                 .data           = &print_fatal_signals,
397                 .maxlen         = sizeof(int),
398                 .mode           = 0644,
399                 .proc_handler   = &proc_dointvec,
400         },
401 #ifdef __sparc__
402         {
403                 .ctl_name       = KERN_SPARC_REBOOT,
404                 .procname       = "reboot-cmd",
405                 .data           = reboot_command,
406                 .maxlen         = 256,
407                 .mode           = 0644,
408                 .proc_handler   = &proc_dostring,
409                 .strategy       = &sysctl_string,
410         },
411         {
412                 .ctl_name       = KERN_SPARC_STOP_A,
413                 .procname       = "stop-a",
414                 .data           = &stop_a_enabled,
415                 .maxlen         = sizeof (int),
416                 .mode           = 0644,
417                 .proc_handler   = &proc_dointvec,
418         },
419         {
420                 .ctl_name       = KERN_SPARC_SCONS_PWROFF,
421                 .procname       = "scons-poweroff",
422                 .data           = &scons_pwroff,
423                 .maxlen         = sizeof (int),
424                 .mode           = 0644,
425                 .proc_handler   = &proc_dointvec,
426         },
427 #endif
428 #ifdef __hppa__
429         {
430                 .ctl_name       = KERN_HPPA_PWRSW,
431                 .procname       = "soft-power",
432                 .data           = &pwrsw_enabled,
433                 .maxlen         = sizeof (int),
434                 .mode           = 0644,
435                 .proc_handler   = &proc_dointvec,
436         },
437         {
438                 .ctl_name       = KERN_HPPA_UNALIGNED,
439                 .procname       = "unaligned-trap",
440                 .data           = &unaligned_enabled,
441                 .maxlen         = sizeof (int),
442                 .mode           = 0644,
443                 .proc_handler   = &proc_dointvec,
444         },
445 #endif
446         {
447                 .ctl_name       = KERN_CTLALTDEL,
448                 .procname       = "ctrl-alt-del",
449                 .data           = &C_A_D,
450                 .maxlen         = sizeof(int),
451                 .mode           = 0644,
452                 .proc_handler   = &proc_dointvec,
453         },
454         {
455                 .ctl_name       = KERN_PRINTK,
456                 .procname       = "printk",
457                 .data           = &console_loglevel,
458                 .maxlen         = 4*sizeof(int),
459                 .mode           = 0644,
460                 .proc_handler   = &proc_dointvec,
461         },
462 #ifdef CONFIG_KMOD
463         {
464                 .ctl_name       = KERN_MODPROBE,
465                 .procname       = "modprobe",
466                 .data           = &modprobe_path,
467                 .maxlen         = KMOD_PATH_LEN,
468                 .mode           = 0644,
469                 .proc_handler   = &proc_dostring,
470                 .strategy       = &sysctl_string,
471         },
472 #endif
473 #if defined(CONFIG_HOTPLUG) && defined(CONFIG_NET)
474         {
475                 .ctl_name       = KERN_HOTPLUG,
476                 .procname       = "hotplug",
477                 .data           = &uevent_helper,
478                 .maxlen         = UEVENT_HELPER_PATH_LEN,
479                 .mode           = 0644,
480                 .proc_handler   = &proc_dostring,
481                 .strategy       = &sysctl_string,
482         },
483 #endif
484 #ifdef CONFIG_CHR_DEV_SG
485         {
486                 .ctl_name       = KERN_SG_BIG_BUFF,
487                 .procname       = "sg-big-buff",
488                 .data           = &sg_big_buff,
489                 .maxlen         = sizeof (int),
490                 .mode           = 0444,
491                 .proc_handler   = &proc_dointvec,
492         },
493 #endif
494 #ifdef CONFIG_BSD_PROCESS_ACCT
495         {
496                 .ctl_name       = KERN_ACCT,
497                 .procname       = "acct",
498                 .data           = &acct_parm,
499                 .maxlen         = 3*sizeof(int),
500                 .mode           = 0644,
501                 .proc_handler   = &proc_dointvec,
502         },
503 #endif
504 #ifdef CONFIG_MAGIC_SYSRQ
505         {
506                 .ctl_name       = KERN_SYSRQ,
507                 .procname       = "sysrq",
508                 .data           = &__sysrq_enabled,
509                 .maxlen         = sizeof (int),
510                 .mode           = 0644,
511                 .proc_handler   = &proc_dointvec,
512         },
513 #endif
514 #ifdef CONFIG_PROC_SYSCTL
515         {
516                 .procname       = "cad_pid",
517                 .data           = NULL,
518                 .maxlen         = sizeof (int),
519                 .mode           = 0600,
520                 .proc_handler   = &proc_do_cad_pid,
521         },
522 #endif
523         {
524                 .ctl_name       = KERN_MAX_THREADS,
525                 .procname       = "threads-max",
526                 .data           = &max_threads,
527                 .maxlen         = sizeof(int),
528                 .mode           = 0644,
529                 .proc_handler   = &proc_dointvec,
530         },
531         {
532                 .ctl_name       = KERN_RANDOM,
533                 .procname       = "random",
534                 .mode           = 0555,
535                 .child          = random_table,
536         },
537         {
538                 .ctl_name       = KERN_OVERFLOWUID,
539                 .procname       = "overflowuid",
540                 .data           = &overflowuid,
541                 .maxlen         = sizeof(int),
542                 .mode           = 0644,
543                 .proc_handler   = &proc_dointvec_minmax,
544                 .strategy       = &sysctl_intvec,
545                 .extra1         = &minolduid,
546                 .extra2         = &maxolduid,
547         },
548         {
549                 .ctl_name       = KERN_OVERFLOWGID,
550                 .procname       = "overflowgid",
551                 .data           = &overflowgid,
552                 .maxlen         = sizeof(int),
553                 .mode           = 0644,
554                 .proc_handler   = &proc_dointvec_minmax,
555                 .strategy       = &sysctl_intvec,
556                 .extra1         = &minolduid,
557                 .extra2         = &maxolduid,
558         },
559 #ifdef CONFIG_S390
560 #ifdef CONFIG_MATHEMU
561         {
562                 .ctl_name       = KERN_IEEE_EMULATION_WARNINGS,
563                 .procname       = "ieee_emulation_warnings",
564                 .data           = &sysctl_ieee_emulation_warnings,
565                 .maxlen         = sizeof(int),
566                 .mode           = 0644,
567                 .proc_handler   = &proc_dointvec,
568         },
569 #endif
570 #ifdef CONFIG_NO_IDLE_HZ
571         {
572                 .ctl_name       = KERN_HZ_TIMER,
573                 .procname       = "hz_timer",
574                 .data           = &sysctl_hz_timer,
575                 .maxlen         = sizeof(int),
576                 .mode           = 0644,
577                 .proc_handler   = &proc_dointvec,
578         },
579 #endif
580         {
581                 .ctl_name       = KERN_S390_USER_DEBUG_LOGGING,
582                 .procname       = "userprocess_debug",
583                 .data           = &sysctl_userprocess_debug,
584                 .maxlen         = sizeof(int),
585                 .mode           = 0644,
586                 .proc_handler   = &proc_dointvec,
587         },
588 #endif
589         {
590                 .ctl_name       = KERN_PIDMAX,
591                 .procname       = "pid_max",
592                 .data           = &pid_max,
593                 .maxlen         = sizeof (int),
594                 .mode           = 0644,
595                 .proc_handler   = &proc_dointvec_minmax,
596                 .strategy       = sysctl_intvec,
597                 .extra1         = &pid_max_min,
598                 .extra2         = &pid_max_max,
599         },
600         {
601                 .ctl_name       = KERN_PANIC_ON_OOPS,
602                 .procname       = "panic_on_oops",
603                 .data           = &panic_on_oops,
604                 .maxlen         = sizeof(int),
605                 .mode           = 0644,
606                 .proc_handler   = &proc_dointvec,
607         },
608         {
609                 .ctl_name       = KERN_PRINTK_RATELIMIT,
610                 .procname       = "printk_ratelimit",
611                 .data           = &printk_ratelimit_jiffies,
612                 .maxlen         = sizeof(int),
613                 .mode           = 0644,
614                 .proc_handler   = &proc_dointvec_jiffies,
615                 .strategy       = &sysctl_jiffies,
616         },
617         {
618                 .ctl_name       = KERN_PRINTK_RATELIMIT_BURST,
619                 .procname       = "printk_ratelimit_burst",
620                 .data           = &printk_ratelimit_burst,
621                 .maxlen         = sizeof(int),
622                 .mode           = 0644,
623                 .proc_handler   = &proc_dointvec,
624         },
625         {
626                 .ctl_name       = KERN_NGROUPS_MAX,
627                 .procname       = "ngroups_max",
628                 .data           = &ngroups_max,
629                 .maxlen         = sizeof (int),
630                 .mode           = 0444,
631                 .proc_handler   = &proc_dointvec,
632         },
633 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
634         {
635                 .ctl_name       = KERN_UNKNOWN_NMI_PANIC,
636                 .procname       = "unknown_nmi_panic",
637                 .data           = &unknown_nmi_panic,
638                 .maxlen         = sizeof (int),
639                 .mode           = 0644,
640                 .proc_handler   = &proc_dointvec,
641         },
642         {
643                 .procname       = "nmi_watchdog",
644                 .data           = &nmi_watchdog_enabled,
645                 .maxlen         = sizeof (int),
646                 .mode           = 0644,
647                 .proc_handler   = &proc_nmi_enabled,
648         },
649 #endif
650 #if defined(CONFIG_X86)
651         {
652                 .ctl_name       = KERN_PANIC_ON_NMI,
653                 .procname       = "panic_on_unrecovered_nmi",
654                 .data           = &panic_on_unrecovered_nmi,
655                 .maxlen         = sizeof(int),
656                 .mode           = 0644,
657                 .proc_handler   = &proc_dointvec,
658         },
659         {
660                 .ctl_name       = KERN_BOOTLOADER_TYPE,
661                 .procname       = "bootloader_type",
662                 .data           = &bootloader_type,
663                 .maxlen         = sizeof (int),
664                 .mode           = 0444,
665                 .proc_handler   = &proc_dointvec,
666         },
667         {
668                 .ctl_name       = CTL_UNNUMBERED,
669                 .procname       = "kstack_depth_to_print",
670                 .data           = &kstack_depth_to_print,
671                 .maxlen         = sizeof(int),
672                 .mode           = 0644,
673                 .proc_handler   = &proc_dointvec,
674         },
675 #endif
676 #if defined(CONFIG_MMU)
677         {
678                 .ctl_name       = KERN_RANDOMIZE,
679                 .procname       = "randomize_va_space",
680                 .data           = &randomize_va_space,
681                 .maxlen         = sizeof(int),
682                 .mode           = 0644,
683                 .proc_handler   = &proc_dointvec,
684         },
685 #endif
686 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
687         {
688                 .ctl_name       = KERN_SPIN_RETRY,
689                 .procname       = "spin_retry",
690                 .data           = &spin_retry,
691                 .maxlen         = sizeof (int),
692                 .mode           = 0644,
693                 .proc_handler   = &proc_dointvec,
694         },
695 #endif
696 #if     defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
697         {
698                 .procname       = "acpi_video_flags",
699                 .data           = &acpi_realmode_flags,
700                 .maxlen         = sizeof (unsigned long),
701                 .mode           = 0644,
702                 .proc_handler   = &proc_doulongvec_minmax,
703         },
704 #endif
705 #ifdef CONFIG_IA64
706         {
707                 .ctl_name       = KERN_IA64_UNALIGNED,
708                 .procname       = "ignore-unaligned-usertrap",
709                 .data           = &no_unaligned_warning,
710                 .maxlen         = sizeof (int),
711                 .mode           = 0644,
712                 .proc_handler   = &proc_dointvec,
713         },
714 #endif
715 #ifdef CONFIG_DETECT_SOFTLOCKUP
716         {
717                 .ctl_name       = CTL_UNNUMBERED,
718                 .procname       = "softlockup_thresh",
719                 .data           = &softlockup_thresh,
720                 .maxlen         = sizeof(int),
721                 .mode           = 0644,
722                 .proc_handler   = &proc_dointvec_minmax,
723                 .strategy       = &sysctl_intvec,
724                 .extra1         = &one,
725                 .extra2         = &sixty,
726         },
727 #endif
728 #ifdef CONFIG_COMPAT
729         {
730                 .ctl_name       = KERN_COMPAT_LOG,
731                 .procname       = "compat-log",
732                 .data           = &compat_log,
733                 .maxlen         = sizeof (int),
734                 .mode           = 0644,
735                 .proc_handler   = &proc_dointvec,
736         },
737 #endif
738 #ifdef CONFIG_RT_MUTEXES
739         {
740                 .ctl_name       = KERN_MAX_LOCK_DEPTH,
741                 .procname       = "max_lock_depth",
742                 .data           = &max_lock_depth,
743                 .maxlen         = sizeof(int),
744                 .mode           = 0644,
745                 .proc_handler   = &proc_dointvec,
746         },
747 #endif
748 #ifdef CONFIG_PROC_FS
749         {
750                 .ctl_name       = CTL_UNNUMBERED,
751                 .procname       = "maps_protect",
752                 .data           = &maps_protect,
753                 .maxlen         = sizeof(int),
754                 .mode           = 0644,
755                 .proc_handler   = &proc_dointvec,
756         },
757 #endif
758         {
759                 .ctl_name       = CTL_UNNUMBERED,
760                 .procname       = "poweroff_cmd",
761                 .data           = &poweroff_cmd,
762                 .maxlen         = POWEROFF_CMD_PATH_LEN,
763                 .mode           = 0644,
764                 .proc_handler   = &proc_dostring,
765                 .strategy       = &sysctl_string,
766         },
767 /*
768  * NOTE: do not add new entries to this table unless you have read
769  * Documentation/sysctl/ctl_unnumbered.txt
770  */
771         { .ctl_name = 0 }
772 };
773
774 static struct ctl_table vm_table[] = {
775         {
776                 .ctl_name       = VM_OVERCOMMIT_MEMORY,
777                 .procname       = "overcommit_memory",
778                 .data           = &sysctl_overcommit_memory,
779                 .maxlen         = sizeof(sysctl_overcommit_memory),
780                 .mode           = 0644,
781                 .proc_handler   = &proc_dointvec,
782         },
783         {
784                 .ctl_name       = VM_PANIC_ON_OOM,
785                 .procname       = "panic_on_oom",
786                 .data           = &sysctl_panic_on_oom,
787                 .maxlen         = sizeof(sysctl_panic_on_oom),
788                 .mode           = 0644,
789                 .proc_handler   = &proc_dointvec,
790         },
791         {
792                 .ctl_name       = CTL_UNNUMBERED,
793                 .procname       = "oom_kill_allocating_task",
794                 .data           = &sysctl_oom_kill_allocating_task,
795                 .maxlen         = sizeof(sysctl_oom_kill_allocating_task),
796                 .mode           = 0644,
797                 .proc_handler   = &proc_dointvec,
798         },
799         {
800                 .ctl_name       = VM_OVERCOMMIT_RATIO,
801                 .procname       = "overcommit_ratio",
802                 .data           = &sysctl_overcommit_ratio,
803                 .maxlen         = sizeof(sysctl_overcommit_ratio),
804                 .mode           = 0644,
805                 .proc_handler   = &proc_dointvec,
806         },
807         {
808                 .ctl_name       = VM_PAGE_CLUSTER,
809                 .procname       = "page-cluster", 
810                 .data           = &page_cluster,
811                 .maxlen         = sizeof(int),
812                 .mode           = 0644,
813                 .proc_handler   = &proc_dointvec,
814         },
815         {
816                 .ctl_name       = VM_DIRTY_BACKGROUND,
817                 .procname       = "dirty_background_ratio",
818                 .data           = &dirty_background_ratio,
819                 .maxlen         = sizeof(dirty_background_ratio),
820                 .mode           = 0644,
821                 .proc_handler   = &proc_dointvec_minmax,
822                 .strategy       = &sysctl_intvec,
823                 .extra1         = &zero,
824                 .extra2         = &one_hundred,
825         },
826         {
827                 .ctl_name       = VM_DIRTY_RATIO,
828                 .procname       = "dirty_ratio",
829                 .data           = &vm_dirty_ratio,
830                 .maxlen         = sizeof(vm_dirty_ratio),
831                 .mode           = 0644,
832                 .proc_handler   = &dirty_ratio_handler,
833                 .strategy       = &sysctl_intvec,
834                 .extra1         = &zero,
835                 .extra2         = &one_hundred,
836         },
837         {
838                 .procname       = "dirty_writeback_centisecs",
839                 .data           = &dirty_writeback_interval,
840                 .maxlen         = sizeof(dirty_writeback_interval),
841                 .mode           = 0644,
842                 .proc_handler   = &dirty_writeback_centisecs_handler,
843         },
844         {
845                 .procname       = "dirty_expire_centisecs",
846                 .data           = &dirty_expire_interval,
847                 .maxlen         = sizeof(dirty_expire_interval),
848                 .mode           = 0644,
849                 .proc_handler   = &proc_dointvec_userhz_jiffies,
850         },
851         {
852                 .ctl_name       = VM_NR_PDFLUSH_THREADS,
853                 .procname       = "nr_pdflush_threads",
854                 .data           = &nr_pdflush_threads,
855                 .maxlen         = sizeof nr_pdflush_threads,
856                 .mode           = 0444 /* read-only*/,
857                 .proc_handler   = &proc_dointvec,
858         },
859         {
860                 .ctl_name       = VM_SWAPPINESS,
861                 .procname       = "swappiness",
862                 .data           = &vm_swappiness,
863                 .maxlen         = sizeof(vm_swappiness),
864                 .mode           = 0644,
865                 .proc_handler   = &proc_dointvec_minmax,
866                 .strategy       = &sysctl_intvec,
867                 .extra1         = &zero,
868                 .extra2         = &one_hundred,
869         },
870 #ifdef CONFIG_HUGETLB_PAGE
871          {
872                 .procname       = "nr_hugepages",
873                 .data           = &max_huge_pages,
874                 .maxlen         = sizeof(unsigned long),
875                 .mode           = 0644,
876                 .proc_handler   = &hugetlb_sysctl_handler,
877                 .extra1         = (void *)&hugetlb_zero,
878                 .extra2         = (void *)&hugetlb_infinity,
879          },
880          {
881                 .ctl_name       = VM_HUGETLB_GROUP,
882                 .procname       = "hugetlb_shm_group",
883                 .data           = &sysctl_hugetlb_shm_group,
884                 .maxlen         = sizeof(gid_t),
885                 .mode           = 0644,
886                 .proc_handler   = &proc_dointvec,
887          },
888          {
889                 .ctl_name       = CTL_UNNUMBERED,
890                 .procname       = "hugepages_treat_as_movable",
891                 .data           = &hugepages_treat_as_movable,
892                 .maxlen         = sizeof(int),
893                 .mode           = 0644,
894                 .proc_handler   = &hugetlb_treat_movable_handler,
895         },
896         {
897                 .ctl_name       = CTL_UNNUMBERED,
898                 .procname       = "hugetlb_dynamic_pool",
899                 .data           = &hugetlb_dynamic_pool,
900                 .maxlen         = sizeof(hugetlb_dynamic_pool),
901                 .mode           = 0644,
902                 .proc_handler   = &proc_dointvec,
903         },
904 #endif
905         {
906                 .ctl_name       = VM_LOWMEM_RESERVE_RATIO,
907                 .procname       = "lowmem_reserve_ratio",
908                 .data           = &sysctl_lowmem_reserve_ratio,
909                 .maxlen         = sizeof(sysctl_lowmem_reserve_ratio),
910                 .mode           = 0644,
911                 .proc_handler   = &lowmem_reserve_ratio_sysctl_handler,
912                 .strategy       = &sysctl_intvec,
913         },
914         {
915                 .ctl_name       = VM_DROP_PAGECACHE,
916                 .procname       = "drop_caches",
917                 .data           = &sysctl_drop_caches,
918                 .maxlen         = sizeof(int),
919                 .mode           = 0644,
920                 .proc_handler   = drop_caches_sysctl_handler,
921                 .strategy       = &sysctl_intvec,
922         },
923         {
924                 .ctl_name       = VM_MIN_FREE_KBYTES,
925                 .procname       = "min_free_kbytes",
926                 .data           = &min_free_kbytes,
927                 .maxlen         = sizeof(min_free_kbytes),
928                 .mode           = 0644,
929                 .proc_handler   = &min_free_kbytes_sysctl_handler,
930                 .strategy       = &sysctl_intvec,
931                 .extra1         = &zero,
932         },
933         {
934                 .ctl_name       = VM_PERCPU_PAGELIST_FRACTION,
935                 .procname       = "percpu_pagelist_fraction",
936                 .data           = &percpu_pagelist_fraction,
937                 .maxlen         = sizeof(percpu_pagelist_fraction),
938                 .mode           = 0644,
939                 .proc_handler   = &percpu_pagelist_fraction_sysctl_handler,
940                 .strategy       = &sysctl_intvec,
941                 .extra1         = &min_percpu_pagelist_fract,
942         },
943 #ifdef CONFIG_MMU
944         {
945                 .ctl_name       = VM_MAX_MAP_COUNT,
946                 .procname       = "max_map_count",
947                 .data           = &sysctl_max_map_count,
948                 .maxlen         = sizeof(sysctl_max_map_count),
949                 .mode           = 0644,
950                 .proc_handler   = &proc_dointvec
951         },
952 #endif
953         {
954                 .ctl_name       = VM_LAPTOP_MODE,
955                 .procname       = "laptop_mode",
956                 .data           = &laptop_mode,
957                 .maxlen         = sizeof(laptop_mode),
958                 .mode           = 0644,
959                 .proc_handler   = &proc_dointvec_jiffies,
960                 .strategy       = &sysctl_jiffies,
961         },
962         {
963                 .ctl_name       = VM_BLOCK_DUMP,
964                 .procname       = "block_dump",
965                 .data           = &block_dump,
966                 .maxlen         = sizeof(block_dump),
967                 .mode           = 0644,
968                 .proc_handler   = &proc_dointvec,
969                 .strategy       = &sysctl_intvec,
970                 .extra1         = &zero,
971         },
972         {
973                 .ctl_name       = VM_VFS_CACHE_PRESSURE,
974                 .procname       = "vfs_cache_pressure",
975                 .data           = &sysctl_vfs_cache_pressure,
976                 .maxlen         = sizeof(sysctl_vfs_cache_pressure),
977                 .mode           = 0644,
978                 .proc_handler   = &proc_dointvec,
979                 .strategy       = &sysctl_intvec,
980                 .extra1         = &zero,
981         },
982 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
983         {
984                 .ctl_name       = VM_LEGACY_VA_LAYOUT,
985                 .procname       = "legacy_va_layout",
986                 .data           = &sysctl_legacy_va_layout,
987                 .maxlen         = sizeof(sysctl_legacy_va_layout),
988                 .mode           = 0644,
989                 .proc_handler   = &proc_dointvec,
990                 .strategy       = &sysctl_intvec,
991                 .extra1         = &zero,
992         },
993 #endif
994 #ifdef CONFIG_NUMA
995         {
996                 .ctl_name       = VM_ZONE_RECLAIM_MODE,
997                 .procname       = "zone_reclaim_mode",
998                 .data           = &zone_reclaim_mode,
999                 .maxlen         = sizeof(zone_reclaim_mode),
1000                 .mode           = 0644,
1001                 .proc_handler   = &proc_dointvec,
1002                 .strategy       = &sysctl_intvec,
1003                 .extra1         = &zero,
1004         },
1005         {
1006                 .ctl_name       = VM_MIN_UNMAPPED,
1007                 .procname       = "min_unmapped_ratio",
1008                 .data           = &sysctl_min_unmapped_ratio,
1009                 .maxlen         = sizeof(sysctl_min_unmapped_ratio),
1010                 .mode           = 0644,
1011                 .proc_handler   = &sysctl_min_unmapped_ratio_sysctl_handler,
1012                 .strategy       = &sysctl_intvec,
1013                 .extra1         = &zero,
1014                 .extra2         = &one_hundred,
1015         },
1016         {
1017                 .ctl_name       = VM_MIN_SLAB,
1018                 .procname       = "min_slab_ratio",
1019                 .data           = &sysctl_min_slab_ratio,
1020                 .maxlen         = sizeof(sysctl_min_slab_ratio),
1021                 .mode           = 0644,
1022                 .proc_handler   = &sysctl_min_slab_ratio_sysctl_handler,
1023                 .strategy       = &sysctl_intvec,
1024                 .extra1         = &zero,
1025                 .extra2         = &one_hundred,
1026         },
1027 #endif
1028 #ifdef CONFIG_SMP
1029         {
1030                 .ctl_name       = CTL_UNNUMBERED,
1031                 .procname       = "stat_interval",
1032                 .data           = &sysctl_stat_interval,
1033                 .maxlen         = sizeof(sysctl_stat_interval),
1034                 .mode           = 0644,
1035                 .proc_handler   = &proc_dointvec_jiffies,
1036                 .strategy       = &sysctl_jiffies,
1037         },
1038 #endif
1039 #ifdef CONFIG_SECURITY
1040         {
1041                 .ctl_name       = CTL_UNNUMBERED,
1042                 .procname       = "mmap_min_addr",
1043                 .data           = &mmap_min_addr,
1044                 .maxlen         = sizeof(unsigned long),
1045                 .mode           = 0644,
1046                 .proc_handler   = &proc_doulongvec_minmax,
1047         },
1048 #endif
1049 #ifdef CONFIG_NUMA
1050         {
1051                 .ctl_name       = CTL_UNNUMBERED,
1052                 .procname       = "numa_zonelist_order",
1053                 .data           = &numa_zonelist_order,
1054                 .maxlen         = NUMA_ZONELIST_ORDER_LEN,
1055                 .mode           = 0644,
1056                 .proc_handler   = &numa_zonelist_order_handler,
1057                 .strategy       = &sysctl_string,
1058         },
1059 #endif
1060 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1061    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1062         {
1063                 .ctl_name       = VM_VDSO_ENABLED,
1064                 .procname       = "vdso_enabled",
1065                 .data           = &vdso_enabled,
1066                 .maxlen         = sizeof(vdso_enabled),
1067                 .mode           = 0644,
1068                 .proc_handler   = &proc_dointvec,
1069                 .strategy       = &sysctl_intvec,
1070                 .extra1         = &zero,
1071         },
1072 #endif
1073 /*
1074  * NOTE: do not add new entries to this table unless you have read
1075  * Documentation/sysctl/ctl_unnumbered.txt
1076  */
1077         { .ctl_name = 0 }
1078 };
1079
1080 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1081 static struct ctl_table binfmt_misc_table[] = {
1082         { .ctl_name = 0 }
1083 };
1084 #endif
1085
1086 static struct ctl_table fs_table[] = {
1087         {
1088                 .ctl_name       = FS_NRINODE,
1089                 .procname       = "inode-nr",
1090                 .data           = &inodes_stat,
1091                 .maxlen         = 2*sizeof(int),
1092                 .mode           = 0444,
1093                 .proc_handler   = &proc_dointvec,
1094         },
1095         {
1096                 .ctl_name       = FS_STATINODE,
1097                 .procname       = "inode-state",
1098                 .data           = &inodes_stat,
1099                 .maxlen         = 7*sizeof(int),
1100                 .mode           = 0444,
1101                 .proc_handler   = &proc_dointvec,
1102         },
1103         {
1104                 .procname       = "file-nr",
1105                 .data           = &files_stat,
1106                 .maxlen         = 3*sizeof(int),
1107                 .mode           = 0444,
1108                 .proc_handler   = &proc_nr_files,
1109         },
1110         {
1111                 .ctl_name       = FS_MAXFILE,
1112                 .procname       = "file-max",
1113                 .data           = &files_stat.max_files,
1114                 .maxlen         = sizeof(int),
1115                 .mode           = 0644,
1116                 .proc_handler   = &proc_dointvec,
1117         },
1118         {
1119                 .ctl_name       = FS_DENTRY,
1120                 .procname       = "dentry-state",
1121                 .data           = &dentry_stat,
1122                 .maxlen         = 6*sizeof(int),
1123                 .mode           = 0444,
1124                 .proc_handler   = &proc_dointvec,
1125         },
1126         {
1127                 .ctl_name       = FS_OVERFLOWUID,
1128                 .procname       = "overflowuid",
1129                 .data           = &fs_overflowuid,
1130                 .maxlen         = sizeof(int),
1131                 .mode           = 0644,
1132                 .proc_handler   = &proc_dointvec_minmax,
1133                 .strategy       = &sysctl_intvec,
1134                 .extra1         = &minolduid,
1135                 .extra2         = &maxolduid,
1136         },
1137         {
1138                 .ctl_name       = FS_OVERFLOWGID,
1139                 .procname       = "overflowgid",
1140                 .data           = &fs_overflowgid,
1141                 .maxlen         = sizeof(int),
1142                 .mode           = 0644,
1143                 .proc_handler   = &proc_dointvec_minmax,
1144                 .strategy       = &sysctl_intvec,
1145                 .extra1         = &minolduid,
1146                 .extra2         = &maxolduid,
1147         },
1148         {
1149                 .ctl_name       = FS_LEASES,
1150                 .procname       = "leases-enable",
1151                 .data           = &leases_enable,
1152                 .maxlen         = sizeof(int),
1153                 .mode           = 0644,
1154                 .proc_handler   = &proc_dointvec,
1155         },
1156 #ifdef CONFIG_DNOTIFY
1157         {
1158                 .ctl_name       = FS_DIR_NOTIFY,
1159                 .procname       = "dir-notify-enable",
1160                 .data           = &dir_notify_enable,
1161                 .maxlen         = sizeof(int),
1162                 .mode           = 0644,
1163                 .proc_handler   = &proc_dointvec,
1164         },
1165 #endif
1166 #ifdef CONFIG_MMU
1167         {
1168                 .ctl_name       = FS_LEASE_TIME,
1169                 .procname       = "lease-break-time",
1170                 .data           = &lease_break_time,
1171                 .maxlen         = sizeof(int),
1172                 .mode           = 0644,
1173                 .proc_handler   = &proc_dointvec_minmax,
1174                 .strategy       = &sysctl_intvec,
1175                 .extra1         = &zero,
1176                 .extra2         = &two,
1177         },
1178         {
1179                 .procname       = "aio-nr",
1180                 .data           = &aio_nr,
1181                 .maxlen         = sizeof(aio_nr),
1182                 .mode           = 0444,
1183                 .proc_handler   = &proc_doulongvec_minmax,
1184         },
1185         {
1186                 .procname       = "aio-max-nr",
1187                 .data           = &aio_max_nr,
1188                 .maxlen         = sizeof(aio_max_nr),
1189                 .mode           = 0644,
1190                 .proc_handler   = &proc_doulongvec_minmax,
1191         },
1192 #ifdef CONFIG_INOTIFY_USER
1193         {
1194                 .ctl_name       = FS_INOTIFY,
1195                 .procname       = "inotify",
1196                 .mode           = 0555,
1197                 .child          = inotify_table,
1198         },
1199 #endif  
1200 #endif
1201         {
1202                 .ctl_name       = KERN_SETUID_DUMPABLE,
1203                 .procname       = "suid_dumpable",
1204                 .data           = &suid_dumpable,
1205                 .maxlen         = sizeof(int),
1206                 .mode           = 0644,
1207                 .proc_handler   = &proc_dointvec,
1208         },
1209 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1210         {
1211                 .ctl_name       = CTL_UNNUMBERED,
1212                 .procname       = "binfmt_misc",
1213                 .mode           = 0555,
1214                 .child          = binfmt_misc_table,
1215         },
1216 #endif
1217 /*
1218  * NOTE: do not add new entries to this table unless you have read
1219  * Documentation/sysctl/ctl_unnumbered.txt
1220  */
1221         { .ctl_name = 0 }
1222 };
1223
1224 static struct ctl_table debug_table[] = {
1225 #if defined(CONFIG_X86) || defined(CONFIG_PPC)
1226         {
1227                 .ctl_name       = CTL_UNNUMBERED,
1228                 .procname       = "exception-trace",
1229                 .data           = &show_unhandled_signals,
1230                 .maxlen         = sizeof(int),
1231                 .mode           = 0644,
1232                 .proc_handler   = proc_dointvec
1233         },
1234 #endif
1235         { .ctl_name = 0 }
1236 };
1237
1238 static struct ctl_table dev_table[] = {
1239         { .ctl_name = 0 }
1240 };
1241
1242 static DEFINE_SPINLOCK(sysctl_lock);
1243
1244 /* called under sysctl_lock */
1245 static int use_table(struct ctl_table_header *p)
1246 {
1247         if (unlikely(p->unregistering))
1248                 return 0;
1249         p->used++;
1250         return 1;
1251 }
1252
1253 /* called under sysctl_lock */
1254 static void unuse_table(struct ctl_table_header *p)
1255 {
1256         if (!--p->used)
1257                 if (unlikely(p->unregistering))
1258                         complete(p->unregistering);
1259 }
1260
1261 /* called under sysctl_lock, will reacquire if has to wait */
1262 static void start_unregistering(struct ctl_table_header *p)
1263 {
1264         /*
1265          * if p->used is 0, nobody will ever touch that entry again;
1266          * we'll eliminate all paths to it before dropping sysctl_lock
1267          */
1268         if (unlikely(p->used)) {
1269                 struct completion wait;
1270                 init_completion(&wait);
1271                 p->unregistering = &wait;
1272                 spin_unlock(&sysctl_lock);
1273                 wait_for_completion(&wait);
1274                 spin_lock(&sysctl_lock);
1275         }
1276         /*
1277          * do not remove from the list until nobody holds it; walking the
1278          * list in do_sysctl() relies on that.
1279          */
1280         list_del_init(&p->ctl_entry);
1281 }
1282
1283 void sysctl_head_finish(struct ctl_table_header *head)
1284 {
1285         if (!head)
1286                 return;
1287         spin_lock(&sysctl_lock);
1288         unuse_table(head);
1289         spin_unlock(&sysctl_lock);
1290 }
1291
1292 struct ctl_table_header *sysctl_head_next(struct ctl_table_header *prev)
1293 {
1294         struct ctl_table_header *head;
1295         struct list_head *tmp;
1296         spin_lock(&sysctl_lock);
1297         if (prev) {
1298                 tmp = &prev->ctl_entry;
1299                 unuse_table(prev);
1300                 goto next;
1301         }
1302         tmp = &root_table_header.ctl_entry;
1303         for (;;) {
1304                 head = list_entry(tmp, struct ctl_table_header, ctl_entry);
1305
1306                 if (!use_table(head))
1307                         goto next;
1308                 spin_unlock(&sysctl_lock);
1309                 return head;
1310         next:
1311                 tmp = tmp->next;
1312                 if (tmp == &root_table_header.ctl_entry)
1313                         break;
1314         }
1315         spin_unlock(&sysctl_lock);
1316         return NULL;
1317 }
1318
1319 #ifdef CONFIG_SYSCTL_SYSCALL
1320 int do_sysctl(int __user *name, int nlen, void __user *oldval, size_t __user *oldlenp,
1321                void __user *newval, size_t newlen)
1322 {
1323         struct ctl_table_header *head;
1324         int error = -ENOTDIR;
1325
1326         if (nlen <= 0 || nlen >= CTL_MAXNAME)
1327                 return -ENOTDIR;
1328         if (oldval) {
1329                 int old_len;
1330                 if (!oldlenp || get_user(old_len, oldlenp))
1331                         return -EFAULT;
1332         }
1333
1334         for (head = sysctl_head_next(NULL); head;
1335                         head = sysctl_head_next(head)) {
1336                 error = parse_table(name, nlen, oldval, oldlenp, 
1337                                         newval, newlen, head->ctl_table);
1338                 if (error != -ENOTDIR) {
1339                         sysctl_head_finish(head);
1340                         break;
1341                 }
1342         }
1343         return error;
1344 }
1345
1346 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
1347 {
1348         struct __sysctl_args tmp;
1349         int error;
1350
1351         if (copy_from_user(&tmp, args, sizeof(tmp)))
1352                 return -EFAULT;
1353
1354         error = deprecated_sysctl_warning(&tmp);
1355         if (error)
1356                 goto out;
1357
1358         lock_kernel();
1359         error = do_sysctl(tmp.name, tmp.nlen, tmp.oldval, tmp.oldlenp,
1360                           tmp.newval, tmp.newlen);
1361         unlock_kernel();
1362 out:
1363         return error;
1364 }
1365 #endif /* CONFIG_SYSCTL_SYSCALL */
1366
1367 /*
1368  * sysctl_perm does NOT grant the superuser all rights automatically, because
1369  * some sysctl variables are readonly even to root.
1370  */
1371
1372 static int test_perm(int mode, int op)
1373 {
1374         if (!current->euid)
1375                 mode >>= 6;
1376         else if (in_egroup_p(0))
1377                 mode >>= 3;
1378         if ((mode & op & 0007) == op)
1379                 return 0;
1380         return -EACCES;
1381 }
1382
1383 int sysctl_perm(struct ctl_table *table, int op)
1384 {
1385         int error;
1386         error = security_sysctl(table, op);
1387         if (error)
1388                 return error;
1389         return test_perm(table->mode, op);
1390 }
1391
1392 #ifdef CONFIG_SYSCTL_SYSCALL
1393 static int parse_table(int __user *name, int nlen,
1394                        void __user *oldval, size_t __user *oldlenp,
1395                        void __user *newval, size_t newlen,
1396                        struct ctl_table *table)
1397 {
1398         int n;
1399 repeat:
1400         if (!nlen)
1401                 return -ENOTDIR;
1402         if (get_user(n, name))
1403                 return -EFAULT;
1404         for ( ; table->ctl_name || table->procname; table++) {
1405                 if (!table->ctl_name)
1406                         continue;
1407                 if (n == table->ctl_name) {
1408                         int error;
1409                         if (table->child) {
1410                                 if (sysctl_perm(table, 001))
1411                                         return -EPERM;
1412                                 name++;
1413                                 nlen--;
1414                                 table = table->child;
1415                                 goto repeat;
1416                         }
1417                         error = do_sysctl_strategy(table, name, nlen,
1418                                                    oldval, oldlenp,
1419                                                    newval, newlen);
1420                         return error;
1421                 }
1422         }
1423         return -ENOTDIR;
1424 }
1425
1426 /* Perform the actual read/write of a sysctl table entry. */
1427 int do_sysctl_strategy (struct ctl_table *table,
1428                         int __user *name, int nlen,
1429                         void __user *oldval, size_t __user *oldlenp,
1430                         void __user *newval, size_t newlen)
1431 {
1432         int op = 0, rc;
1433
1434         if (oldval)
1435                 op |= 004;
1436         if (newval) 
1437                 op |= 002;
1438         if (sysctl_perm(table, op))
1439                 return -EPERM;
1440
1441         if (table->strategy) {
1442                 rc = table->strategy(table, name, nlen, oldval, oldlenp,
1443                                      newval, newlen);
1444                 if (rc < 0)
1445                         return rc;
1446                 if (rc > 0)
1447                         return 0;
1448         }
1449
1450         /* If there is no strategy routine, or if the strategy returns
1451          * zero, proceed with automatic r/w */
1452         if (table->data && table->maxlen) {
1453                 rc = sysctl_data(table, name, nlen, oldval, oldlenp,
1454                                  newval, newlen);
1455                 if (rc < 0)
1456                         return rc;
1457         }
1458         return 0;
1459 }
1460 #endif /* CONFIG_SYSCTL_SYSCALL */
1461
1462 static void sysctl_set_parent(struct ctl_table *parent, struct ctl_table *table)
1463 {
1464         for (; table->ctl_name || table->procname; table++) {
1465                 table->parent = parent;
1466                 if (table->child)
1467                         sysctl_set_parent(table, table->child);
1468         }
1469 }
1470
1471 static __init int sysctl_init(void)
1472 {
1473         int err;
1474         sysctl_set_parent(NULL, root_table);
1475         err = sysctl_check_table(root_table);
1476         return 0;
1477 }
1478
1479 core_initcall(sysctl_init);
1480
1481 /**
1482  * register_sysctl_table - register a sysctl hierarchy
1483  * @table: the top-level table structure
1484  *
1485  * Register a sysctl table hierarchy. @table should be a filled in ctl_table
1486  * array. An entry with a ctl_name of 0 terminates the table. 
1487  *
1488  * The members of the &struct ctl_table structure are used as follows:
1489  *
1490  * ctl_name - This is the numeric sysctl value used by sysctl(2). The number
1491  *            must be unique within that level of sysctl
1492  *
1493  * procname - the name of the sysctl file under /proc/sys. Set to %NULL to not
1494  *            enter a sysctl file
1495  *
1496  * data - a pointer to data for use by proc_handler
1497  *
1498  * maxlen - the maximum size in bytes of the data
1499  *
1500  * mode - the file permissions for the /proc/sys file, and for sysctl(2)
1501  *
1502  * child - a pointer to the child sysctl table if this entry is a directory, or
1503  *         %NULL.
1504  *
1505  * proc_handler - the text handler routine (described below)
1506  *
1507  * strategy - the strategy routine (described below)
1508  *
1509  * de - for internal use by the sysctl routines
1510  *
1511  * extra1, extra2 - extra pointers usable by the proc handler routines
1512  *
1513  * Leaf nodes in the sysctl tree will be represented by a single file
1514  * under /proc; non-leaf nodes will be represented by directories.
1515  *
1516  * sysctl(2) can automatically manage read and write requests through
1517  * the sysctl table.  The data and maxlen fields of the ctl_table
1518  * struct enable minimal validation of the values being written to be
1519  * performed, and the mode field allows minimal authentication.
1520  *
1521  * More sophisticated management can be enabled by the provision of a
1522  * strategy routine with the table entry.  This will be called before
1523  * any automatic read or write of the data is performed.
1524  *
1525  * The strategy routine may return
1526  *
1527  * < 0 - Error occurred (error is passed to user process)
1528  *
1529  * 0   - OK - proceed with automatic read or write.
1530  *
1531  * > 0 - OK - read or write has been done by the strategy routine, so
1532  *       return immediately.
1533  *
1534  * There must be a proc_handler routine for any terminal nodes
1535  * mirrored under /proc/sys (non-terminals are handled by a built-in
1536  * directory handler).  Several default handlers are available to
1537  * cover common cases -
1538  *
1539  * proc_dostring(), proc_dointvec(), proc_dointvec_jiffies(),
1540  * proc_dointvec_userhz_jiffies(), proc_dointvec_minmax(), 
1541  * proc_doulongvec_ms_jiffies_minmax(), proc_doulongvec_minmax()
1542  *
1543  * It is the handler's job to read the input buffer from user memory
1544  * and process it. The handler should return 0 on success.
1545  *
1546  * This routine returns %NULL on a failure to register, and a pointer
1547  * to the table header on success.
1548  */
1549 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1550 {
1551         struct ctl_table_header *tmp;
1552         tmp = kmalloc(sizeof(struct ctl_table_header), GFP_KERNEL);
1553         if (!tmp)
1554                 return NULL;
1555         tmp->ctl_table = table;
1556         INIT_LIST_HEAD(&tmp->ctl_entry);
1557         tmp->used = 0;
1558         tmp->unregistering = NULL;
1559         sysctl_set_parent(NULL, table);
1560         if (sysctl_check_table(tmp->ctl_table)) {
1561                 kfree(tmp);
1562                 return NULL;
1563         }
1564         spin_lock(&sysctl_lock);
1565         list_add_tail(&tmp->ctl_entry, &root_table_header.ctl_entry);
1566         spin_unlock(&sysctl_lock);
1567         return tmp;
1568 }
1569
1570 /**
1571  * unregister_sysctl_table - unregister a sysctl table hierarchy
1572  * @header: the header returned from register_sysctl_table
1573  *
1574  * Unregisters the sysctl table and all children. proc entries may not
1575  * actually be removed until they are no longer used by anyone.
1576  */
1577 void unregister_sysctl_table(struct ctl_table_header * header)
1578 {
1579         might_sleep();
1580         spin_lock(&sysctl_lock);
1581         start_unregistering(header);
1582         spin_unlock(&sysctl_lock);
1583         kfree(header);
1584 }
1585
1586 #else /* !CONFIG_SYSCTL */
1587 struct ctl_table_header *register_sysctl_table(struct ctl_table * table)
1588 {
1589         return NULL;
1590 }
1591
1592 void unregister_sysctl_table(struct ctl_table_header * table)
1593 {
1594 }
1595
1596 #endif /* CONFIG_SYSCTL */
1597
1598 /*
1599  * /proc/sys support
1600  */
1601
1602 #ifdef CONFIG_PROC_SYSCTL
1603
1604 static int _proc_do_string(void* data, int maxlen, int write,
1605                            struct file *filp, void __user *buffer,
1606                            size_t *lenp, loff_t *ppos)
1607 {
1608         size_t len;
1609         char __user *p;
1610         char c;
1611
1612         if (!data || !maxlen || !*lenp) {
1613                 *lenp = 0;
1614                 return 0;
1615         }
1616
1617         if (write) {
1618                 len = 0;
1619                 p = buffer;
1620                 while (len < *lenp) {
1621                         if (get_user(c, p++))
1622                                 return -EFAULT;
1623                         if (c == 0 || c == '\n')
1624                                 break;
1625                         len++;
1626                 }
1627                 if (len >= maxlen)
1628                         len = maxlen-1;
1629                 if(copy_from_user(data, buffer, len))
1630                         return -EFAULT;
1631                 ((char *) data)[len] = 0;
1632                 *ppos += *lenp;
1633         } else {
1634                 len = strlen(data);
1635                 if (len > maxlen)
1636                         len = maxlen;
1637
1638                 if (*ppos > len) {
1639                         *lenp = 0;
1640                         return 0;
1641                 }
1642
1643                 data += *ppos;
1644                 len  -= *ppos;
1645
1646                 if (len > *lenp)
1647                         len = *lenp;
1648                 if (len)
1649                         if(copy_to_user(buffer, data, len))
1650                                 return -EFAULT;
1651                 if (len < *lenp) {
1652                         if(put_user('\n', ((char __user *) buffer) + len))
1653                                 return -EFAULT;
1654                         len++;
1655                 }
1656                 *lenp = len;
1657                 *ppos += len;
1658         }
1659         return 0;
1660 }
1661
1662 /**
1663  * proc_dostring - read a string sysctl
1664  * @table: the sysctl table
1665  * @write: %TRUE if this is a write to the sysctl file
1666  * @filp: the file structure
1667  * @buffer: the user buffer
1668  * @lenp: the size of the user buffer
1669  * @ppos: file position
1670  *
1671  * Reads/writes a string from/to the user buffer. If the kernel
1672  * buffer provided is not large enough to hold the string, the
1673  * string is truncated. The copied string is %NULL-terminated.
1674  * If the string is being read by the user process, it is copied
1675  * and a newline '\n' is added. It is truncated if the buffer is
1676  * not large enough.
1677  *
1678  * Returns 0 on success.
1679  */
1680 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
1681                   void __user *buffer, size_t *lenp, loff_t *ppos)
1682 {
1683         return _proc_do_string(table->data, table->maxlen, write, filp,
1684                                buffer, lenp, ppos);
1685 }
1686
1687
1688 static int do_proc_dointvec_conv(int *negp, unsigned long *lvalp,
1689                                  int *valp,
1690                                  int write, void *data)
1691 {
1692         if (write) {
1693                 *valp = *negp ? -*lvalp : *lvalp;
1694         } else {
1695                 int val = *valp;
1696                 if (val < 0) {
1697                         *negp = -1;
1698                         *lvalp = (unsigned long)-val;
1699                 } else {
1700                         *negp = 0;
1701                         *lvalp = (unsigned long)val;
1702                 }
1703         }
1704         return 0;
1705 }
1706
1707 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
1708                   int write, struct file *filp, void __user *buffer,
1709                   size_t *lenp, loff_t *ppos,
1710                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1711                               int write, void *data),
1712                   void *data)
1713 {
1714 #define TMPBUFLEN 21
1715         int *i, vleft, first=1, neg, val;
1716         unsigned long lval;
1717         size_t left, len;
1718         
1719         char buf[TMPBUFLEN], *p;
1720         char __user *s = buffer;
1721         
1722         if (!tbl_data || !table->maxlen || !*lenp ||
1723             (*ppos && !write)) {
1724                 *lenp = 0;
1725                 return 0;
1726         }
1727         
1728         i = (int *) tbl_data;
1729         vleft = table->maxlen / sizeof(*i);
1730         left = *lenp;
1731
1732         if (!conv)
1733                 conv = do_proc_dointvec_conv;
1734
1735         for (; left && vleft--; i++, first=0) {
1736                 if (write) {
1737                         while (left) {
1738                                 char c;
1739                                 if (get_user(c, s))
1740                                         return -EFAULT;
1741                                 if (!isspace(c))
1742                                         break;
1743                                 left--;
1744                                 s++;
1745                         }
1746                         if (!left)
1747                                 break;
1748                         neg = 0;
1749                         len = left;
1750                         if (len > sizeof(buf) - 1)
1751                                 len = sizeof(buf) - 1;
1752                         if (copy_from_user(buf, s, len))
1753                                 return -EFAULT;
1754                         buf[len] = 0;
1755                         p = buf;
1756                         if (*p == '-' && left > 1) {
1757                                 neg = 1;
1758                                 p++;
1759                         }
1760                         if (*p < '0' || *p > '9')
1761                                 break;
1762
1763                         lval = simple_strtoul(p, &p, 0);
1764
1765                         len = p-buf;
1766                         if ((len < left) && *p && !isspace(*p))
1767                                 break;
1768                         if (neg)
1769                                 val = -val;
1770                         s += len;
1771                         left -= len;
1772
1773                         if (conv(&neg, &lval, i, 1, data))
1774                                 break;
1775                 } else {
1776                         p = buf;
1777                         if (!first)
1778                                 *p++ = '\t';
1779         
1780                         if (conv(&neg, &lval, i, 0, data))
1781                                 break;
1782
1783                         sprintf(p, "%s%lu", neg ? "-" : "", lval);
1784                         len = strlen(buf);
1785                         if (len > left)
1786                                 len = left;
1787                         if(copy_to_user(s, buf, len))
1788                                 return -EFAULT;
1789                         left -= len;
1790                         s += len;
1791                 }
1792         }
1793
1794         if (!write && !first && left) {
1795                 if(put_user('\n', s))
1796                         return -EFAULT;
1797                 left--, s++;
1798         }
1799         if (write) {
1800                 while (left) {
1801                         char c;
1802                         if (get_user(c, s++))
1803                                 return -EFAULT;
1804                         if (!isspace(c))
1805                                 break;
1806                         left--;
1807                 }
1808         }
1809         if (write && first)
1810                 return -EINVAL;
1811         *lenp -= left;
1812         *ppos += *lenp;
1813         return 0;
1814 #undef TMPBUFLEN
1815 }
1816
1817 static int do_proc_dointvec(struct ctl_table *table, int write, struct file *filp,
1818                   void __user *buffer, size_t *lenp, loff_t *ppos,
1819                   int (*conv)(int *negp, unsigned long *lvalp, int *valp,
1820                               int write, void *data),
1821                   void *data)
1822 {
1823         return __do_proc_dointvec(table->data, table, write, filp,
1824                         buffer, lenp, ppos, conv, data);
1825 }
1826
1827 /**
1828  * proc_dointvec - read a vector of integers
1829  * @table: the sysctl table
1830  * @write: %TRUE if this is a write to the sysctl file
1831  * @filp: the file structure
1832  * @buffer: the user buffer
1833  * @lenp: the size of the user buffer
1834  * @ppos: file position
1835  *
1836  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1837  * values from/to the user buffer, treated as an ASCII string. 
1838  *
1839  * Returns 0 on success.
1840  */
1841 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
1842                      void __user *buffer, size_t *lenp, loff_t *ppos)
1843 {
1844     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1845                             NULL,NULL);
1846 }
1847
1848 #define OP_SET  0
1849 #define OP_AND  1
1850 #define OP_OR   2
1851
1852 static int do_proc_dointvec_bset_conv(int *negp, unsigned long *lvalp,
1853                                       int *valp,
1854                                       int write, void *data)
1855 {
1856         int op = *(int *)data;
1857         if (write) {
1858                 int val = *negp ? -*lvalp : *lvalp;
1859                 switch(op) {
1860                 case OP_SET:    *valp = val; break;
1861                 case OP_AND:    *valp &= val; break;
1862                 case OP_OR:     *valp |= val; break;
1863                 }
1864         } else {
1865                 int val = *valp;
1866                 if (val < 0) {
1867                         *negp = -1;
1868                         *lvalp = (unsigned long)-val;
1869                 } else {
1870                         *negp = 0;
1871                         *lvalp = (unsigned long)val;
1872                 }
1873         }
1874         return 0;
1875 }
1876
1877 #ifdef CONFIG_SECURITY_CAPABILITIES
1878 /*
1879  *      init may raise the set.
1880  */
1881
1882 int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp,
1883                         void __user *buffer, size_t *lenp, loff_t *ppos)
1884 {
1885         int op;
1886
1887         if (write && !capable(CAP_SYS_MODULE)) {
1888                 return -EPERM;
1889         }
1890
1891         op = is_init(current) ? OP_SET : OP_AND;
1892         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1893                                 do_proc_dointvec_bset_conv,&op);
1894 }
1895 #endif /* def CONFIG_SECURITY_CAPABILITIES */
1896
1897 /*
1898  *      Taint values can only be increased
1899  */
1900 static int proc_dointvec_taint(struct ctl_table *table, int write, struct file *filp,
1901                                void __user *buffer, size_t *lenp, loff_t *ppos)
1902 {
1903         int op;
1904
1905         if (write && !capable(CAP_SYS_ADMIN))
1906                 return -EPERM;
1907
1908         op = OP_OR;
1909         return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
1910                                 do_proc_dointvec_bset_conv,&op);
1911 }
1912
1913 struct do_proc_dointvec_minmax_conv_param {
1914         int *min;
1915         int *max;
1916 };
1917
1918 static int do_proc_dointvec_minmax_conv(int *negp, unsigned long *lvalp, 
1919                                         int *valp, 
1920                                         int write, void *data)
1921 {
1922         struct do_proc_dointvec_minmax_conv_param *param = data;
1923         if (write) {
1924                 int val = *negp ? -*lvalp : *lvalp;
1925                 if ((param->min && *param->min > val) ||
1926                     (param->max && *param->max < val))
1927                         return -EINVAL;
1928                 *valp = val;
1929         } else {
1930                 int val = *valp;
1931                 if (val < 0) {
1932                         *negp = -1;
1933                         *lvalp = (unsigned long)-val;
1934                 } else {
1935                         *negp = 0;
1936                         *lvalp = (unsigned long)val;
1937                 }
1938         }
1939         return 0;
1940 }
1941
1942 /**
1943  * proc_dointvec_minmax - read a vector of integers with min/max values
1944  * @table: the sysctl table
1945  * @write: %TRUE if this is a write to the sysctl file
1946  * @filp: the file structure
1947  * @buffer: the user buffer
1948  * @lenp: the size of the user buffer
1949  * @ppos: file position
1950  *
1951  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1952  * values from/to the user buffer, treated as an ASCII string.
1953  *
1954  * This routine will ensure the values are within the range specified by
1955  * table->extra1 (min) and table->extra2 (max).
1956  *
1957  * Returns 0 on success.
1958  */
1959 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
1960                   void __user *buffer, size_t *lenp, loff_t *ppos)
1961 {
1962         struct do_proc_dointvec_minmax_conv_param param = {
1963                 .min = (int *) table->extra1,
1964                 .max = (int *) table->extra2,
1965         };
1966         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
1967                                 do_proc_dointvec_minmax_conv, &param);
1968 }
1969
1970 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
1971                                      struct file *filp,
1972                                      void __user *buffer,
1973                                      size_t *lenp, loff_t *ppos,
1974                                      unsigned long convmul,
1975                                      unsigned long convdiv)
1976 {
1977 #define TMPBUFLEN 21
1978         unsigned long *i, *min, *max, val;
1979         int vleft, first=1, neg;
1980         size_t len, left;
1981         char buf[TMPBUFLEN], *p;
1982         char __user *s = buffer;
1983         
1984         if (!data || !table->maxlen || !*lenp ||
1985             (*ppos && !write)) {
1986                 *lenp = 0;
1987                 return 0;
1988         }
1989         
1990         i = (unsigned long *) data;
1991         min = (unsigned long *) table->extra1;
1992         max = (unsigned long *) table->extra2;
1993         vleft = table->maxlen / sizeof(unsigned long);
1994         left = *lenp;
1995         
1996         for (; left && vleft--; i++, min++, max++, first=0) {
1997                 if (write) {
1998                         while (left) {
1999                                 char c;
2000                                 if (get_user(c, s))
2001                                         return -EFAULT;
2002                                 if (!isspace(c))
2003                                         break;
2004                                 left--;
2005                                 s++;
2006                         }
2007                         if (!left)
2008                                 break;
2009                         neg = 0;
2010                         len = left;
2011                         if (len > TMPBUFLEN-1)
2012                                 len = TMPBUFLEN-1;
2013                         if (copy_from_user(buf, s, len))
2014                                 return -EFAULT;
2015                         buf[len] = 0;
2016                         p = buf;
2017                         if (*p == '-' && left > 1) {
2018                                 neg = 1;
2019                                 p++;
2020                         }
2021                         if (*p < '0' || *p > '9')
2022                                 break;
2023                         val = simple_strtoul(p, &p, 0) * convmul / convdiv ;
2024                         len = p-buf;
2025                         if ((len < left) && *p && !isspace(*p))
2026                                 break;
2027                         if (neg)
2028                                 val = -val;
2029                         s += len;
2030                         left -= len;
2031
2032                         if(neg)
2033                                 continue;
2034                         if ((min && val < *min) || (max && val > *max))
2035                                 continue;
2036                         *i = val;
2037                 } else {
2038                         p = buf;
2039                         if (!first)
2040                                 *p++ = '\t';
2041                         sprintf(p, "%lu", convdiv * (*i) / convmul);
2042                         len = strlen(buf);
2043                         if (len > left)
2044                                 len = left;
2045                         if(copy_to_user(s, buf, len))
2046                                 return -EFAULT;
2047                         left -= len;
2048                         s += len;
2049                 }
2050         }
2051
2052         if (!write && !first && left) {
2053                 if(put_user('\n', s))
2054                         return -EFAULT;
2055                 left--, s++;
2056         }
2057         if (write) {
2058                 while (left) {
2059                         char c;
2060                         if (get_user(c, s++))
2061                                 return -EFAULT;
2062                         if (!isspace(c))
2063                                 break;
2064                         left--;
2065                 }
2066         }
2067         if (write && first)
2068                 return -EINVAL;
2069         *lenp -= left;
2070         *ppos += *lenp;
2071         return 0;
2072 #undef TMPBUFLEN
2073 }
2074
2075 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2076                                      struct file *filp,
2077                                      void __user *buffer,
2078                                      size_t *lenp, loff_t *ppos,
2079                                      unsigned long convmul,
2080                                      unsigned long convdiv)
2081 {
2082         return __do_proc_doulongvec_minmax(table->data, table, write,
2083                         filp, buffer, lenp, ppos, convmul, convdiv);
2084 }
2085
2086 /**
2087  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2088  * @table: the sysctl table
2089  * @write: %TRUE if this is a write to the sysctl file
2090  * @filp: the file structure
2091  * @buffer: the user buffer
2092  * @lenp: the size of the user buffer
2093  * @ppos: file position
2094  *
2095  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2096  * values from/to the user buffer, treated as an ASCII string.
2097  *
2098  * This routine will ensure the values are within the range specified by
2099  * table->extra1 (min) and table->extra2 (max).
2100  *
2101  * Returns 0 on success.
2102  */
2103 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2104                            void __user *buffer, size_t *lenp, loff_t *ppos)
2105 {
2106     return do_proc_doulongvec_minmax(table, write, filp, buffer, lenp, ppos, 1l, 1l);
2107 }
2108
2109 /**
2110  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2111  * @table: the sysctl table
2112  * @write: %TRUE if this is a write to the sysctl file
2113  * @filp: the file structure
2114  * @buffer: the user buffer
2115  * @lenp: the size of the user buffer
2116  * @ppos: file position
2117  *
2118  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2119  * values from/to the user buffer, treated as an ASCII string. The values
2120  * are treated as milliseconds, and converted to jiffies when they are stored.
2121  *
2122  * This routine will ensure the values are within the range specified by
2123  * table->extra1 (min) and table->extra2 (max).
2124  *
2125  * Returns 0 on success.
2126  */
2127 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2128                                       struct file *filp,
2129                                       void __user *buffer,
2130                                       size_t *lenp, loff_t *ppos)
2131 {
2132     return do_proc_doulongvec_minmax(table, write, filp, buffer,
2133                                      lenp, ppos, HZ, 1000l);
2134 }
2135
2136
2137 static int do_proc_dointvec_jiffies_conv(int *negp, unsigned long *lvalp,
2138                                          int *valp,
2139                                          int write, void *data)
2140 {
2141         if (write) {
2142                 if (*lvalp > LONG_MAX / HZ)
2143                         return 1;
2144                 *valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2145         } else {
2146                 int val = *valp;
2147                 unsigned long lval;
2148                 if (val < 0) {
2149                         *negp = -1;
2150                         lval = (unsigned long)-val;
2151                 } else {
2152                         *negp = 0;
2153                         lval = (unsigned long)val;
2154                 }
2155                 *lvalp = lval / HZ;
2156         }
2157         return 0;
2158 }
2159
2160 static int do_proc_dointvec_userhz_jiffies_conv(int *negp, unsigned long *lvalp,
2161                                                 int *valp,
2162                                                 int write, void *data)
2163 {
2164         if (write) {
2165                 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2166                         return 1;
2167                 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2168         } else {
2169                 int val = *valp;
2170                 unsigned long lval;
2171                 if (val < 0) {
2172                         *negp = -1;
2173                         lval = (unsigned long)-val;
2174                 } else {
2175                         *negp = 0;
2176                         lval = (unsigned long)val;
2177                 }
2178                 *lvalp = jiffies_to_clock_t(lval);
2179         }
2180         return 0;
2181 }
2182
2183 static int do_proc_dointvec_ms_jiffies_conv(int *negp, unsigned long *lvalp,
2184                                             int *valp,
2185                                             int write, void *data)
2186 {
2187         if (write) {
2188                 *valp = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2189         } else {
2190                 int val = *valp;
2191                 unsigned long lval;
2192                 if (val < 0) {
2193                         *negp = -1;
2194                         lval = (unsigned long)-val;
2195                 } else {
2196                         *negp = 0;
2197                         lval = (unsigned long)val;
2198                 }
2199                 *lvalp = jiffies_to_msecs(lval);
2200         }
2201         return 0;
2202 }
2203
2204 /**
2205  * proc_dointvec_jiffies - read a vector of integers as seconds
2206  * @table: the sysctl table
2207  * @write: %TRUE if this is a write to the sysctl file
2208  * @filp: the file structure
2209  * @buffer: the user buffer
2210  * @lenp: the size of the user buffer
2211  * @ppos: file position
2212  *
2213  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2214  * values from/to the user buffer, treated as an ASCII string. 
2215  * The values read are assumed to be in seconds, and are converted into
2216  * jiffies.
2217  *
2218  * Returns 0 on success.
2219  */
2220 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2221                           void __user *buffer, size_t *lenp, loff_t *ppos)
2222 {
2223     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2224                             do_proc_dointvec_jiffies_conv,NULL);
2225 }
2226
2227 /**
2228  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2229  * @table: the sysctl table
2230  * @write: %TRUE if this is a write to the sysctl file
2231  * @filp: the file structure
2232  * @buffer: the user buffer
2233  * @lenp: the size of the user buffer
2234  * @ppos: pointer to the file position
2235  *
2236  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2237  * values from/to the user buffer, treated as an ASCII string. 
2238  * The values read are assumed to be in 1/USER_HZ seconds, and 
2239  * are converted into jiffies.
2240  *
2241  * Returns 0 on success.
2242  */
2243 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2244                                  void __user *buffer, size_t *lenp, loff_t *ppos)
2245 {
2246     return do_proc_dointvec(table,write,filp,buffer,lenp,ppos,
2247                             do_proc_dointvec_userhz_jiffies_conv,NULL);
2248 }
2249
2250 /**
2251  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2252  * @table: the sysctl table
2253  * @write: %TRUE if this is a write to the sysctl file
2254  * @filp: the file structure
2255  * @buffer: the user buffer
2256  * @lenp: the size of the user buffer
2257  * @ppos: file position
2258  * @ppos: the current position in the file
2259  *
2260  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2261  * values from/to the user buffer, treated as an ASCII string. 
2262  * The values read are assumed to be in 1/1000 seconds, and 
2263  * are converted into jiffies.
2264  *
2265  * Returns 0 on success.
2266  */
2267 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2268                              void __user *buffer, size_t *lenp, loff_t *ppos)
2269 {
2270         return do_proc_dointvec(table, write, filp, buffer, lenp, ppos,
2271                                 do_proc_dointvec_ms_jiffies_conv, NULL);
2272 }
2273
2274 static int proc_do_cad_pid(struct ctl_table *table, int write, struct file *filp,
2275                            void __user *buffer, size_t *lenp, loff_t *ppos)
2276 {
2277         struct pid *new_pid;
2278         pid_t tmp;
2279         int r;
2280
2281         tmp = pid_nr(cad_pid);
2282
2283         r = __do_proc_dointvec(&tmp, table, write, filp, buffer,
2284                                lenp, ppos, NULL, NULL);
2285         if (r || !write)
2286                 return r;
2287
2288         new_pid = find_get_pid(tmp);
2289         if (!new_pid)
2290                 return -ESRCH;
2291
2292         put_pid(xchg(&cad_pid, new_pid));
2293         return 0;
2294 }
2295
2296 #else /* CONFIG_PROC_FS */
2297
2298 int proc_dostring(struct ctl_table *table, int write, struct file *filp,
2299                   void __user *buffer, size_t *lenp, loff_t *ppos)
2300 {
2301         return -ENOSYS;
2302 }
2303
2304 int proc_dointvec(struct ctl_table *table, int write, struct file *filp,
2305                   void __user *buffer, size_t *lenp, loff_t *ppos)
2306 {
2307         return -ENOSYS;
2308 }
2309
2310 int proc_dointvec_bset(struct ctl_table *table, int write, struct file *filp,
2311                         void __user *buffer, size_t *lenp, loff_t *ppos)
2312 {
2313         return -ENOSYS;
2314 }
2315
2316 int proc_dointvec_minmax(struct ctl_table *table, int write, struct file *filp,
2317                     void __user *buffer, size_t *lenp, loff_t *ppos)
2318 {
2319         return -ENOSYS;
2320 }
2321
2322 int proc_dointvec_jiffies(struct ctl_table *table, int write, struct file *filp,
2323                     void __user *buffer, size_t *lenp, loff_t *ppos)
2324 {
2325         return -ENOSYS;
2326 }
2327
2328 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write, struct file *filp,
2329                     void __user *buffer, size_t *lenp, loff_t *ppos)
2330 {
2331         return -ENOSYS;
2332 }
2333
2334 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, struct file *filp,
2335                              void __user *buffer, size_t *lenp, loff_t *ppos)
2336 {
2337         return -ENOSYS;
2338 }
2339
2340 int proc_doulongvec_minmax(struct ctl_table *table, int write, struct file *filp,
2341                     void __user *buffer, size_t *lenp, loff_t *ppos)
2342 {
2343         return -ENOSYS;
2344 }
2345
2346 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2347                                       struct file *filp,
2348                                       void __user *buffer,
2349                                       size_t *lenp, loff_t *ppos)
2350 {
2351     return -ENOSYS;
2352 }
2353
2354
2355 #endif /* CONFIG_PROC_FS */
2356
2357
2358 #ifdef CONFIG_SYSCTL_SYSCALL
2359 /*
2360  * General sysctl support routines 
2361  */
2362
2363 /* The generic sysctl data routine (used if no strategy routine supplied) */
2364 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2365                 void __user *oldval, size_t __user *oldlenp,
2366                 void __user *newval, size_t newlen)
2367 {
2368         size_t len;
2369
2370         /* Get out of I don't have a variable */
2371         if (!table->data || !table->maxlen)
2372                 return -ENOTDIR;
2373
2374         if (oldval && oldlenp) {
2375                 if (get_user(len, oldlenp))
2376                         return -EFAULT;
2377                 if (len) {
2378                         if (len > table->maxlen)
2379                                 len = table->maxlen;
2380                         if (copy_to_user(oldval, table->data, len))
2381                                 return -EFAULT;
2382                         if (put_user(len, oldlenp))
2383                                 return -EFAULT;
2384                 }
2385         }
2386
2387         if (newval && newlen) {
2388                 if (newlen > table->maxlen)
2389                         newlen = table->maxlen;
2390
2391                 if (copy_from_user(table->data, newval, newlen))
2392                         return -EFAULT;
2393         }
2394         return 1;
2395 }
2396
2397 /* The generic string strategy routine: */
2398 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2399                   void __user *oldval, size_t __user *oldlenp,
2400                   void __user *newval, size_t newlen)
2401 {
2402         if (!table->data || !table->maxlen) 
2403                 return -ENOTDIR;
2404         
2405         if (oldval && oldlenp) {
2406                 size_t bufsize;
2407                 if (get_user(bufsize, oldlenp))
2408                         return -EFAULT;
2409                 if (bufsize) {
2410                         size_t len = strlen(table->data), copied;
2411
2412                         /* This shouldn't trigger for a well-formed sysctl */
2413                         if (len > table->maxlen)
2414                                 len = table->maxlen;
2415
2416                         /* Copy up to a max of bufsize-1 bytes of the string */
2417                         copied = (len >= bufsize) ? bufsize - 1 : len;
2418
2419                         if (copy_to_user(oldval, table->data, copied) ||
2420                             put_user(0, (char __user *)(oldval + copied)))
2421                                 return -EFAULT;
2422                         if (put_user(len, oldlenp))
2423                                 return -EFAULT;
2424                 }
2425         }
2426         if (newval && newlen) {
2427                 size_t len = newlen;
2428                 if (len > table->maxlen)
2429                         len = table->maxlen;
2430                 if(copy_from_user(table->data, newval, len))
2431                         return -EFAULT;
2432                 if (len == table->maxlen)
2433                         len--;
2434                 ((char *) table->data)[len] = 0;
2435         }
2436         return 1;
2437 }
2438
2439 /*
2440  * This function makes sure that all of the integers in the vector
2441  * are between the minimum and maximum values given in the arrays
2442  * table->extra1 and table->extra2, respectively.
2443  */
2444 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2445                 void __user *oldval, size_t __user *oldlenp,
2446                 void __user *newval, size_t newlen)
2447 {
2448
2449         if (newval && newlen) {
2450                 int __user *vec = (int __user *) newval;
2451                 int *min = (int *) table->extra1;
2452                 int *max = (int *) table->extra2;
2453                 size_t length;
2454                 int i;
2455
2456                 if (newlen % sizeof(int) != 0)
2457                         return -EINVAL;
2458
2459                 if (!table->extra1 && !table->extra2)
2460                         return 0;
2461
2462                 if (newlen > table->maxlen)
2463                         newlen = table->maxlen;
2464                 length = newlen / sizeof(int);
2465
2466                 for (i = 0; i < length; i++) {
2467                         int value;
2468                         if (get_user(value, vec + i))
2469                                 return -EFAULT;
2470                         if (min && value < min[i])
2471                                 return -EINVAL;
2472                         if (max && value > max[i])
2473                                 return -EINVAL;
2474                 }
2475         }
2476         return 0;
2477 }
2478
2479 /* Strategy function to convert jiffies to seconds */ 
2480 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2481                 void __user *oldval, size_t __user *oldlenp,
2482                 void __user *newval, size_t newlen)
2483 {
2484         if (oldval && oldlenp) {
2485                 size_t olen;
2486
2487                 if (get_user(olen, oldlenp))
2488                         return -EFAULT;
2489                 if (olen) {
2490                         int val;
2491
2492                         if (olen < sizeof(int))
2493                                 return -EINVAL;
2494
2495                         val = *(int *)(table->data) / HZ;
2496                         if (put_user(val, (int __user *)oldval))
2497                                 return -EFAULT;
2498                         if (put_user(sizeof(int), oldlenp))
2499                                 return -EFAULT;
2500                 }
2501         }
2502         if (newval && newlen) { 
2503                 int new;
2504                 if (newlen != sizeof(int))
2505                         return -EINVAL; 
2506                 if (get_user(new, (int __user *)newval))
2507                         return -EFAULT;
2508                 *(int *)(table->data) = new*HZ; 
2509         }
2510         return 1;
2511 }
2512
2513 /* Strategy function to convert jiffies to seconds */ 
2514 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2515                 void __user *oldval, size_t __user *oldlenp,
2516                 void __user *newval, size_t newlen)
2517 {
2518         if (oldval && oldlenp) {
2519                 size_t olen;
2520
2521                 if (get_user(olen, oldlenp))
2522                         return -EFAULT;
2523                 if (olen) {
2524                         int val;
2525
2526                         if (olen < sizeof(int))
2527                                 return -EINVAL;
2528
2529                         val = jiffies_to_msecs(*(int *)(table->data));
2530                         if (put_user(val, (int __user *)oldval))
2531                                 return -EFAULT;
2532                         if (put_user(sizeof(int), oldlenp))
2533                                 return -EFAULT;
2534                 }
2535         }
2536         if (newval && newlen) { 
2537                 int new;
2538                 if (newlen != sizeof(int))
2539                         return -EINVAL; 
2540                 if (get_user(new, (int __user *)newval))
2541                         return -EFAULT;
2542                 *(int *)(table->data) = msecs_to_jiffies(new);
2543         }
2544         return 1;
2545 }
2546
2547
2548
2549 #else /* CONFIG_SYSCTL_SYSCALL */
2550
2551
2552 asmlinkage long sys_sysctl(struct __sysctl_args __user *args)
2553 {
2554         struct __sysctl_args tmp;
2555         int error;
2556
2557         if (copy_from_user(&tmp, args, sizeof(tmp)))
2558                 return -EFAULT;
2559
2560         error = deprecated_sysctl_warning(&tmp);
2561
2562         /* If no error reading the parameters then just -ENOSYS ... */
2563         if (!error)
2564                 error = -ENOSYS;
2565
2566         return error;
2567 }
2568
2569 int sysctl_data(struct ctl_table *table, int __user *name, int nlen,
2570                   void __user *oldval, size_t __user *oldlenp,
2571                   void __user *newval, size_t newlen)
2572 {
2573         return -ENOSYS;
2574 }
2575
2576 int sysctl_string(struct ctl_table *table, int __user *name, int nlen,
2577                   void __user *oldval, size_t __user *oldlenp,
2578                   void __user *newval, size_t newlen)
2579 {
2580         return -ENOSYS;
2581 }
2582
2583 int sysctl_intvec(struct ctl_table *table, int __user *name, int nlen,
2584                 void __user *oldval, size_t __user *oldlenp,
2585                 void __user *newval, size_t newlen)
2586 {
2587         return -ENOSYS;
2588 }
2589
2590 int sysctl_jiffies(struct ctl_table *table, int __user *name, int nlen,
2591                 void __user *oldval, size_t __user *oldlenp,
2592                 void __user *newval, size_t newlen)
2593 {
2594         return -ENOSYS;
2595 }
2596
2597 int sysctl_ms_jiffies(struct ctl_table *table, int __user *name, int nlen,
2598                 void __user *oldval, size_t __user *oldlenp,
2599                 void __user *newval, size_t newlen)
2600 {
2601         return -ENOSYS;
2602 }
2603
2604 #endif /* CONFIG_SYSCTL_SYSCALL */
2605
2606 static int deprecated_sysctl_warning(struct __sysctl_args *args)
2607 {
2608         static int msg_count;
2609         int name[CTL_MAXNAME];
2610         int i;
2611
2612         /* Read in the sysctl name for better debug message logging */
2613         for (i = 0; i < args->nlen; i++)
2614                 if (get_user(name[i], args->name + i))
2615                         return -EFAULT;
2616
2617         /* Ignore accesses to kernel.version */
2618         if ((args->nlen == 2) && (name[0] == CTL_KERN) && (name[1] == KERN_VERSION))
2619                 return 0;
2620
2621         if (msg_count < 5) {
2622                 msg_count++;
2623                 printk(KERN_INFO
2624                         "warning: process `%s' used the deprecated sysctl "
2625                         "system call with ", current->comm);
2626                 for (i = 0; i < args->nlen; i++)
2627                         printk("%d.", name[i]);
2628                 printk("\n");
2629         }
2630         return 0;
2631 }
2632
2633 /*
2634  * No sense putting this after each symbol definition, twice,
2635  * exception granted :-)
2636  */
2637 EXPORT_SYMBOL(proc_dointvec);
2638 EXPORT_SYMBOL(proc_dointvec_jiffies);
2639 EXPORT_SYMBOL(proc_dointvec_minmax);
2640 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2641 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2642 EXPORT_SYMBOL(proc_dostring);
2643 EXPORT_SYMBOL(proc_doulongvec_minmax);
2644 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2645 EXPORT_SYMBOL(register_sysctl_table);
2646 EXPORT_SYMBOL(sysctl_intvec);
2647 EXPORT_SYMBOL(sysctl_jiffies);
2648 EXPORT_SYMBOL(sysctl_ms_jiffies);
2649 EXPORT_SYMBOL(sysctl_string);
2650 EXPORT_SYMBOL(sysctl_data);
2651 EXPORT_SYMBOL(unregister_sysctl_table);