xref: /linux-6.15/kernel/sysctl.c (revision bd727816)
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/bitmap.h>
27 #include <linux/signal.h>
28 #include <linux/printk.h>
29 #include <linux/proc_fs.h>
30 #include <linux/security.h>
31 #include <linux/ctype.h>
32 #include <linux/kmemcheck.h>
33 #include <linux/kmemleak.h>
34 #include <linux/fs.h>
35 #include <linux/init.h>
36 #include <linux/kernel.h>
37 #include <linux/kobject.h>
38 #include <linux/net.h>
39 #include <linux/sysrq.h>
40 #include <linux/highuid.h>
41 #include <linux/writeback.h>
42 #include <linux/ratelimit.h>
43 #include <linux/compaction.h>
44 #include <linux/hugetlb.h>
45 #include <linux/initrd.h>
46 #include <linux/key.h>
47 #include <linux/times.h>
48 #include <linux/limits.h>
49 #include <linux/dcache.h>
50 #include <linux/dnotify.h>
51 #include <linux/syscalls.h>
52 #include <linux/vmstat.h>
53 #include <linux/nfs_fs.h>
54 #include <linux/acpi.h>
55 #include <linux/reboot.h>
56 #include <linux/ftrace.h>
57 #include <linux/perf_event.h>
58 #include <linux/kprobes.h>
59 #include <linux/pipe_fs_i.h>
60 #include <linux/oom.h>
61 #include <linux/kmod.h>
62 #include <linux/capability.h>
63 #include <linux/binfmts.h>
64 #include <linux/sched/sysctl.h>
65 
66 #include <asm/uaccess.h>
67 #include <asm/processor.h>
68 
69 #ifdef CONFIG_X86
70 #include <asm/nmi.h>
71 #include <asm/stacktrace.h>
72 #include <asm/io.h>
73 #endif
74 #ifdef CONFIG_SPARC
75 #include <asm/setup.h>
76 #endif
77 #ifdef CONFIG_BSD_PROCESS_ACCT
78 #include <linux/acct.h>
79 #endif
80 #ifdef CONFIG_RT_MUTEXES
81 #include <linux/rtmutex.h>
82 #endif
83 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
84 #include <linux/lockdep.h>
85 #endif
86 #ifdef CONFIG_CHR_DEV_SG
87 #include <scsi/sg.h>
88 #endif
89 
90 #ifdef CONFIG_LOCKUP_DETECTOR
91 #include <linux/nmi.h>
92 #endif
93 
94 
95 #if defined(CONFIG_SYSCTL)
96 
97 /* External variables not in a header file. */
98 extern int max_threads;
99 extern int suid_dumpable;
100 #ifdef CONFIG_COREDUMP
101 extern int core_uses_pid;
102 extern char core_pattern[];
103 extern unsigned int core_pipe_limit;
104 #endif
105 extern int pid_max;
106 extern int pid_max_min, pid_max_max;
107 extern int percpu_pagelist_fraction;
108 extern int compat_log;
109 extern int latencytop_enabled;
110 extern int sysctl_nr_open_min, sysctl_nr_open_max;
111 #ifndef CONFIG_MMU
112 extern int sysctl_nr_trim_pages;
113 #endif
114 #ifdef CONFIG_BLOCK
115 extern int blk_iopoll_enabled;
116 #endif
117 
118 /* Constants used for minimum and  maximum */
119 #ifdef CONFIG_LOCKUP_DETECTOR
120 static int sixty = 60;
121 #endif
122 
123 static int zero;
124 static int __maybe_unused one = 1;
125 static int __maybe_unused two = 2;
126 static int __maybe_unused three = 3;
127 static unsigned long one_ul = 1;
128 static int one_hundred = 100;
129 #ifdef CONFIG_PRINTK
130 static int ten_thousand = 10000;
131 #endif
132 
133 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
134 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
135 
136 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
137 static int maxolduid = 65535;
138 static int minolduid;
139 static int min_percpu_pagelist_fract = 8;
140 
141 static int ngroups_max = NGROUPS_MAX;
142 static const int cap_last_cap = CAP_LAST_CAP;
143 
144 #ifdef CONFIG_INOTIFY_USER
145 #include <linux/inotify.h>
146 #endif
147 #ifdef CONFIG_SPARC
148 #endif
149 
150 #ifdef CONFIG_SPARC64
151 extern int sysctl_tsb_ratio;
152 #endif
153 
154 #ifdef __hppa__
155 extern int pwrsw_enabled;
156 #endif
157 
158 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
159 extern int unaligned_enabled;
160 #endif
161 
162 #ifdef CONFIG_IA64
163 extern int unaligned_dump_stack;
164 #endif
165 
166 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
167 extern int no_unaligned_warning;
168 #endif
169 
170 #ifdef CONFIG_PROC_SYSCTL
171 static int proc_do_cad_pid(struct ctl_table *table, int write,
172 		  void __user *buffer, size_t *lenp, loff_t *ppos);
173 static int proc_taint(struct ctl_table *table, int write,
174 			       void __user *buffer, size_t *lenp, loff_t *ppos);
175 #endif
176 
177 #ifdef CONFIG_PRINTK
178 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
179 				void __user *buffer, size_t *lenp, loff_t *ppos);
180 #endif
181 
182 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
183 		void __user *buffer, size_t *lenp, loff_t *ppos);
184 #ifdef CONFIG_COREDUMP
185 static int proc_dostring_coredump(struct ctl_table *table, int write,
186 		void __user *buffer, size_t *lenp, loff_t *ppos);
187 #endif
188 
189 #ifdef CONFIG_MAGIC_SYSRQ
190 /* Note: sysrq code uses it's own private copy */
191 static int __sysrq_enabled = CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE;
192 
193 static int sysrq_sysctl_handler(ctl_table *table, int write,
194 				void __user *buffer, size_t *lenp,
195 				loff_t *ppos)
196 {
197 	int error;
198 
199 	error = proc_dointvec(table, write, buffer, lenp, ppos);
200 	if (error)
201 		return error;
202 
203 	if (write)
204 		sysrq_toggle_support(__sysrq_enabled);
205 
206 	return 0;
207 }
208 
209 #endif
210 
211 static struct ctl_table kern_table[];
212 static struct ctl_table vm_table[];
213 static struct ctl_table fs_table[];
214 static struct ctl_table debug_table[];
215 static struct ctl_table dev_table[];
216 extern struct ctl_table random_table[];
217 #ifdef CONFIG_EPOLL
218 extern struct ctl_table epoll_table[];
219 #endif
220 
221 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
222 int sysctl_legacy_va_layout;
223 #endif
224 
225 /* The default sysctl tables: */
226 
227 static struct ctl_table sysctl_base_table[] = {
228 	{
229 		.procname	= "kernel",
230 		.mode		= 0555,
231 		.child		= kern_table,
232 	},
233 	{
234 		.procname	= "vm",
235 		.mode		= 0555,
236 		.child		= vm_table,
237 	},
238 	{
239 		.procname	= "fs",
240 		.mode		= 0555,
241 		.child		= fs_table,
242 	},
243 	{
244 		.procname	= "debug",
245 		.mode		= 0555,
246 		.child		= debug_table,
247 	},
248 	{
249 		.procname	= "dev",
250 		.mode		= 0555,
251 		.child		= dev_table,
252 	},
253 	{ }
254 };
255 
256 #ifdef CONFIG_SCHED_DEBUG
257 static int min_sched_granularity_ns = 100000;		/* 100 usecs */
258 static int max_sched_granularity_ns = NSEC_PER_SEC;	/* 1 second */
259 static int min_wakeup_granularity_ns;			/* 0 usecs */
260 static int max_wakeup_granularity_ns = NSEC_PER_SEC;	/* 1 second */
261 #ifdef CONFIG_SMP
262 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
263 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
264 #endif /* CONFIG_SMP */
265 #endif /* CONFIG_SCHED_DEBUG */
266 
267 #ifdef CONFIG_COMPACTION
268 static int min_extfrag_threshold;
269 static int max_extfrag_threshold = 1000;
270 #endif
271 
272 static struct ctl_table kern_table[] = {
273 	{
274 		.procname	= "sched_child_runs_first",
275 		.data		= &sysctl_sched_child_runs_first,
276 		.maxlen		= sizeof(unsigned int),
277 		.mode		= 0644,
278 		.proc_handler	= proc_dointvec,
279 	},
280 #ifdef CONFIG_SCHED_DEBUG
281 	{
282 		.procname	= "sched_min_granularity_ns",
283 		.data		= &sysctl_sched_min_granularity,
284 		.maxlen		= sizeof(unsigned int),
285 		.mode		= 0644,
286 		.proc_handler	= sched_proc_update_handler,
287 		.extra1		= &min_sched_granularity_ns,
288 		.extra2		= &max_sched_granularity_ns,
289 	},
290 	{
291 		.procname	= "sched_latency_ns",
292 		.data		= &sysctl_sched_latency,
293 		.maxlen		= sizeof(unsigned int),
294 		.mode		= 0644,
295 		.proc_handler	= sched_proc_update_handler,
296 		.extra1		= &min_sched_granularity_ns,
297 		.extra2		= &max_sched_granularity_ns,
298 	},
299 	{
300 		.procname	= "sched_wakeup_granularity_ns",
301 		.data		= &sysctl_sched_wakeup_granularity,
302 		.maxlen		= sizeof(unsigned int),
303 		.mode		= 0644,
304 		.proc_handler	= sched_proc_update_handler,
305 		.extra1		= &min_wakeup_granularity_ns,
306 		.extra2		= &max_wakeup_granularity_ns,
307 	},
308 #ifdef CONFIG_SMP
309 	{
310 		.procname	= "sched_tunable_scaling",
311 		.data		= &sysctl_sched_tunable_scaling,
312 		.maxlen		= sizeof(enum sched_tunable_scaling),
313 		.mode		= 0644,
314 		.proc_handler	= sched_proc_update_handler,
315 		.extra1		= &min_sched_tunable_scaling,
316 		.extra2		= &max_sched_tunable_scaling,
317 	},
318 	{
319 		.procname	= "sched_migration_cost_ns",
320 		.data		= &sysctl_sched_migration_cost,
321 		.maxlen		= sizeof(unsigned int),
322 		.mode		= 0644,
323 		.proc_handler	= proc_dointvec,
324 	},
325 	{
326 		.procname	= "sched_nr_migrate",
327 		.data		= &sysctl_sched_nr_migrate,
328 		.maxlen		= sizeof(unsigned int),
329 		.mode		= 0644,
330 		.proc_handler	= proc_dointvec,
331 	},
332 	{
333 		.procname	= "sched_time_avg_ms",
334 		.data		= &sysctl_sched_time_avg,
335 		.maxlen		= sizeof(unsigned int),
336 		.mode		= 0644,
337 		.proc_handler	= proc_dointvec,
338 	},
339 	{
340 		.procname	= "sched_shares_window_ns",
341 		.data		= &sysctl_sched_shares_window,
342 		.maxlen		= sizeof(unsigned int),
343 		.mode		= 0644,
344 		.proc_handler	= proc_dointvec,
345 	},
346 	{
347 		.procname	= "timer_migration",
348 		.data		= &sysctl_timer_migration,
349 		.maxlen		= sizeof(unsigned int),
350 		.mode		= 0644,
351 		.proc_handler	= proc_dointvec_minmax,
352 		.extra1		= &zero,
353 		.extra2		= &one,
354 	},
355 #endif /* CONFIG_SMP */
356 #ifdef CONFIG_NUMA_BALANCING
357 	{
358 		.procname	= "numa_balancing_scan_delay_ms",
359 		.data		= &sysctl_numa_balancing_scan_delay,
360 		.maxlen		= sizeof(unsigned int),
361 		.mode		= 0644,
362 		.proc_handler	= proc_dointvec,
363 	},
364 	{
365 		.procname	= "numa_balancing_scan_period_min_ms",
366 		.data		= &sysctl_numa_balancing_scan_period_min,
367 		.maxlen		= sizeof(unsigned int),
368 		.mode		= 0644,
369 		.proc_handler	= proc_dointvec,
370 	},
371 	{
372 		.procname	= "numa_balancing_scan_period_max_ms",
373 		.data		= &sysctl_numa_balancing_scan_period_max,
374 		.maxlen		= sizeof(unsigned int),
375 		.mode		= 0644,
376 		.proc_handler	= proc_dointvec,
377 	},
378 	{
379 		.procname	= "numa_balancing_scan_size_mb",
380 		.data		= &sysctl_numa_balancing_scan_size,
381 		.maxlen		= sizeof(unsigned int),
382 		.mode		= 0644,
383 		.proc_handler	= proc_dointvec,
384 	},
385 	{
386 		.procname       = "numa_balancing_migrate_deferred",
387 		.data           = &sysctl_numa_balancing_migrate_deferred,
388 		.maxlen         = sizeof(unsigned int),
389 		.mode           = 0644,
390 		.proc_handler   = proc_dointvec,
391 	},
392 	{
393 		.procname	= "numa_balancing",
394 		.data		= NULL, /* filled in by handler */
395 		.maxlen		= sizeof(unsigned int),
396 		.mode		= 0644,
397 		.proc_handler	= sysctl_numa_balancing,
398 		.extra1		= &zero,
399 		.extra2		= &one,
400 	},
401 #endif /* CONFIG_NUMA_BALANCING */
402 #endif /* CONFIG_SCHED_DEBUG */
403 	{
404 		.procname	= "sched_rt_period_us",
405 		.data		= &sysctl_sched_rt_period,
406 		.maxlen		= sizeof(unsigned int),
407 		.mode		= 0644,
408 		.proc_handler	= sched_rt_handler,
409 	},
410 	{
411 		.procname	= "sched_rt_runtime_us",
412 		.data		= &sysctl_sched_rt_runtime,
413 		.maxlen		= sizeof(int),
414 		.mode		= 0644,
415 		.proc_handler	= sched_rt_handler,
416 	},
417 	{
418 		.procname	= "sched_rr_timeslice_ms",
419 		.data		= &sched_rr_timeslice,
420 		.maxlen		= sizeof(int),
421 		.mode		= 0644,
422 		.proc_handler	= sched_rr_handler,
423 	},
424 #ifdef CONFIG_SCHED_AUTOGROUP
425 	{
426 		.procname	= "sched_autogroup_enabled",
427 		.data		= &sysctl_sched_autogroup_enabled,
428 		.maxlen		= sizeof(unsigned int),
429 		.mode		= 0644,
430 		.proc_handler	= proc_dointvec_minmax,
431 		.extra1		= &zero,
432 		.extra2		= &one,
433 	},
434 #endif
435 #ifdef CONFIG_CFS_BANDWIDTH
436 	{
437 		.procname	= "sched_cfs_bandwidth_slice_us",
438 		.data		= &sysctl_sched_cfs_bandwidth_slice,
439 		.maxlen		= sizeof(unsigned int),
440 		.mode		= 0644,
441 		.proc_handler	= proc_dointvec_minmax,
442 		.extra1		= &one,
443 	},
444 #endif
445 #ifdef CONFIG_PROVE_LOCKING
446 	{
447 		.procname	= "prove_locking",
448 		.data		= &prove_locking,
449 		.maxlen		= sizeof(int),
450 		.mode		= 0644,
451 		.proc_handler	= proc_dointvec,
452 	},
453 #endif
454 #ifdef CONFIG_LOCK_STAT
455 	{
456 		.procname	= "lock_stat",
457 		.data		= &lock_stat,
458 		.maxlen		= sizeof(int),
459 		.mode		= 0644,
460 		.proc_handler	= proc_dointvec,
461 	},
462 #endif
463 	{
464 		.procname	= "panic",
465 		.data		= &panic_timeout,
466 		.maxlen		= sizeof(int),
467 		.mode		= 0644,
468 		.proc_handler	= proc_dointvec,
469 	},
470 #ifdef CONFIG_COREDUMP
471 	{
472 		.procname	= "core_uses_pid",
473 		.data		= &core_uses_pid,
474 		.maxlen		= sizeof(int),
475 		.mode		= 0644,
476 		.proc_handler	= proc_dointvec,
477 	},
478 	{
479 		.procname	= "core_pattern",
480 		.data		= core_pattern,
481 		.maxlen		= CORENAME_MAX_SIZE,
482 		.mode		= 0644,
483 		.proc_handler	= proc_dostring_coredump,
484 	},
485 	{
486 		.procname	= "core_pipe_limit",
487 		.data		= &core_pipe_limit,
488 		.maxlen		= sizeof(unsigned int),
489 		.mode		= 0644,
490 		.proc_handler	= proc_dointvec,
491 	},
492 #endif
493 #ifdef CONFIG_PROC_SYSCTL
494 	{
495 		.procname	= "tainted",
496 		.maxlen 	= sizeof(long),
497 		.mode		= 0644,
498 		.proc_handler	= proc_taint,
499 	},
500 #endif
501 #ifdef CONFIG_LATENCYTOP
502 	{
503 		.procname	= "latencytop",
504 		.data		= &latencytop_enabled,
505 		.maxlen		= sizeof(int),
506 		.mode		= 0644,
507 		.proc_handler	= proc_dointvec,
508 	},
509 #endif
510 #ifdef CONFIG_BLK_DEV_INITRD
511 	{
512 		.procname	= "real-root-dev",
513 		.data		= &real_root_dev,
514 		.maxlen		= sizeof(int),
515 		.mode		= 0644,
516 		.proc_handler	= proc_dointvec,
517 	},
518 #endif
519 	{
520 		.procname	= "print-fatal-signals",
521 		.data		= &print_fatal_signals,
522 		.maxlen		= sizeof(int),
523 		.mode		= 0644,
524 		.proc_handler	= proc_dointvec,
525 	},
526 #ifdef CONFIG_SPARC
527 	{
528 		.procname	= "reboot-cmd",
529 		.data		= reboot_command,
530 		.maxlen		= 256,
531 		.mode		= 0644,
532 		.proc_handler	= proc_dostring,
533 	},
534 	{
535 		.procname	= "stop-a",
536 		.data		= &stop_a_enabled,
537 		.maxlen		= sizeof (int),
538 		.mode		= 0644,
539 		.proc_handler	= proc_dointvec,
540 	},
541 	{
542 		.procname	= "scons-poweroff",
543 		.data		= &scons_pwroff,
544 		.maxlen		= sizeof (int),
545 		.mode		= 0644,
546 		.proc_handler	= proc_dointvec,
547 	},
548 #endif
549 #ifdef CONFIG_SPARC64
550 	{
551 		.procname	= "tsb-ratio",
552 		.data		= &sysctl_tsb_ratio,
553 		.maxlen		= sizeof (int),
554 		.mode		= 0644,
555 		.proc_handler	= proc_dointvec,
556 	},
557 #endif
558 #ifdef __hppa__
559 	{
560 		.procname	= "soft-power",
561 		.data		= &pwrsw_enabled,
562 		.maxlen		= sizeof (int),
563 	 	.mode		= 0644,
564 		.proc_handler	= proc_dointvec,
565 	},
566 #endif
567 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
568 	{
569 		.procname	= "unaligned-trap",
570 		.data		= &unaligned_enabled,
571 		.maxlen		= sizeof (int),
572 		.mode		= 0644,
573 		.proc_handler	= proc_dointvec,
574 	},
575 #endif
576 	{
577 		.procname	= "ctrl-alt-del",
578 		.data		= &C_A_D,
579 		.maxlen		= sizeof(int),
580 		.mode		= 0644,
581 		.proc_handler	= proc_dointvec,
582 	},
583 #ifdef CONFIG_FUNCTION_TRACER
584 	{
585 		.procname	= "ftrace_enabled",
586 		.data		= &ftrace_enabled,
587 		.maxlen		= sizeof(int),
588 		.mode		= 0644,
589 		.proc_handler	= ftrace_enable_sysctl,
590 	},
591 #endif
592 #ifdef CONFIG_STACK_TRACER
593 	{
594 		.procname	= "stack_tracer_enabled",
595 		.data		= &stack_tracer_enabled,
596 		.maxlen		= sizeof(int),
597 		.mode		= 0644,
598 		.proc_handler	= stack_trace_sysctl,
599 	},
600 #endif
601 #ifdef CONFIG_TRACING
602 	{
603 		.procname	= "ftrace_dump_on_oops",
604 		.data		= &ftrace_dump_on_oops,
605 		.maxlen		= sizeof(int),
606 		.mode		= 0644,
607 		.proc_handler	= proc_dointvec,
608 	},
609 	{
610 		.procname	= "traceoff_on_warning",
611 		.data		= &__disable_trace_on_warning,
612 		.maxlen		= sizeof(__disable_trace_on_warning),
613 		.mode		= 0644,
614 		.proc_handler	= proc_dointvec,
615 	},
616 #endif
617 #ifdef CONFIG_MODULES
618 	{
619 		.procname	= "modprobe",
620 		.data		= &modprobe_path,
621 		.maxlen		= KMOD_PATH_LEN,
622 		.mode		= 0644,
623 		.proc_handler	= proc_dostring,
624 	},
625 	{
626 		.procname	= "modules_disabled",
627 		.data		= &modules_disabled,
628 		.maxlen		= sizeof(int),
629 		.mode		= 0644,
630 		/* only handle a transition from default "0" to "1" */
631 		.proc_handler	= proc_dointvec_minmax,
632 		.extra1		= &one,
633 		.extra2		= &one,
634 	},
635 #endif
636 
637 	{
638 		.procname	= "hotplug",
639 		.data		= &uevent_helper,
640 		.maxlen		= UEVENT_HELPER_PATH_LEN,
641 		.mode		= 0644,
642 		.proc_handler	= proc_dostring,
643 	},
644 
645 #ifdef CONFIG_CHR_DEV_SG
646 	{
647 		.procname	= "sg-big-buff",
648 		.data		= &sg_big_buff,
649 		.maxlen		= sizeof (int),
650 		.mode		= 0444,
651 		.proc_handler	= proc_dointvec,
652 	},
653 #endif
654 #ifdef CONFIG_BSD_PROCESS_ACCT
655 	{
656 		.procname	= "acct",
657 		.data		= &acct_parm,
658 		.maxlen		= 3*sizeof(int),
659 		.mode		= 0644,
660 		.proc_handler	= proc_dointvec,
661 	},
662 #endif
663 #ifdef CONFIG_MAGIC_SYSRQ
664 	{
665 		.procname	= "sysrq",
666 		.data		= &__sysrq_enabled,
667 		.maxlen		= sizeof (int),
668 		.mode		= 0644,
669 		.proc_handler	= sysrq_sysctl_handler,
670 	},
671 #endif
672 #ifdef CONFIG_PROC_SYSCTL
673 	{
674 		.procname	= "cad_pid",
675 		.data		= NULL,
676 		.maxlen		= sizeof (int),
677 		.mode		= 0600,
678 		.proc_handler	= proc_do_cad_pid,
679 	},
680 #endif
681 	{
682 		.procname	= "threads-max",
683 		.data		= &max_threads,
684 		.maxlen		= sizeof(int),
685 		.mode		= 0644,
686 		.proc_handler	= proc_dointvec,
687 	},
688 	{
689 		.procname	= "random",
690 		.mode		= 0555,
691 		.child		= random_table,
692 	},
693 	{
694 		.procname	= "usermodehelper",
695 		.mode		= 0555,
696 		.child		= usermodehelper_table,
697 	},
698 	{
699 		.procname	= "overflowuid",
700 		.data		= &overflowuid,
701 		.maxlen		= sizeof(int),
702 		.mode		= 0644,
703 		.proc_handler	= proc_dointvec_minmax,
704 		.extra1		= &minolduid,
705 		.extra2		= &maxolduid,
706 	},
707 	{
708 		.procname	= "overflowgid",
709 		.data		= &overflowgid,
710 		.maxlen		= sizeof(int),
711 		.mode		= 0644,
712 		.proc_handler	= proc_dointvec_minmax,
713 		.extra1		= &minolduid,
714 		.extra2		= &maxolduid,
715 	},
716 #ifdef CONFIG_S390
717 #ifdef CONFIG_MATHEMU
718 	{
719 		.procname	= "ieee_emulation_warnings",
720 		.data		= &sysctl_ieee_emulation_warnings,
721 		.maxlen		= sizeof(int),
722 		.mode		= 0644,
723 		.proc_handler	= proc_dointvec,
724 	},
725 #endif
726 	{
727 		.procname	= "userprocess_debug",
728 		.data		= &show_unhandled_signals,
729 		.maxlen		= sizeof(int),
730 		.mode		= 0644,
731 		.proc_handler	= proc_dointvec,
732 	},
733 #endif
734 	{
735 		.procname	= "pid_max",
736 		.data		= &pid_max,
737 		.maxlen		= sizeof (int),
738 		.mode		= 0644,
739 		.proc_handler	= proc_dointvec_minmax,
740 		.extra1		= &pid_max_min,
741 		.extra2		= &pid_max_max,
742 	},
743 	{
744 		.procname	= "panic_on_oops",
745 		.data		= &panic_on_oops,
746 		.maxlen		= sizeof(int),
747 		.mode		= 0644,
748 		.proc_handler	= proc_dointvec,
749 	},
750 #if defined CONFIG_PRINTK
751 	{
752 		.procname	= "printk",
753 		.data		= &console_loglevel,
754 		.maxlen		= 4*sizeof(int),
755 		.mode		= 0644,
756 		.proc_handler	= proc_dointvec,
757 	},
758 	{
759 		.procname	= "printk_ratelimit",
760 		.data		= &printk_ratelimit_state.interval,
761 		.maxlen		= sizeof(int),
762 		.mode		= 0644,
763 		.proc_handler	= proc_dointvec_jiffies,
764 	},
765 	{
766 		.procname	= "printk_ratelimit_burst",
767 		.data		= &printk_ratelimit_state.burst,
768 		.maxlen		= sizeof(int),
769 		.mode		= 0644,
770 		.proc_handler	= proc_dointvec,
771 	},
772 	{
773 		.procname	= "printk_delay",
774 		.data		= &printk_delay_msec,
775 		.maxlen		= sizeof(int),
776 		.mode		= 0644,
777 		.proc_handler	= proc_dointvec_minmax,
778 		.extra1		= &zero,
779 		.extra2		= &ten_thousand,
780 	},
781 	{
782 		.procname	= "dmesg_restrict",
783 		.data		= &dmesg_restrict,
784 		.maxlen		= sizeof(int),
785 		.mode		= 0644,
786 		.proc_handler	= proc_dointvec_minmax_sysadmin,
787 		.extra1		= &zero,
788 		.extra2		= &one,
789 	},
790 	{
791 		.procname	= "kptr_restrict",
792 		.data		= &kptr_restrict,
793 		.maxlen		= sizeof(int),
794 		.mode		= 0644,
795 		.proc_handler	= proc_dointvec_minmax_sysadmin,
796 		.extra1		= &zero,
797 		.extra2		= &two,
798 	},
799 #endif
800 	{
801 		.procname	= "ngroups_max",
802 		.data		= &ngroups_max,
803 		.maxlen		= sizeof (int),
804 		.mode		= 0444,
805 		.proc_handler	= proc_dointvec,
806 	},
807 	{
808 		.procname	= "cap_last_cap",
809 		.data		= (void *)&cap_last_cap,
810 		.maxlen		= sizeof(int),
811 		.mode		= 0444,
812 		.proc_handler	= proc_dointvec,
813 	},
814 #if defined(CONFIG_LOCKUP_DETECTOR)
815 	{
816 		.procname       = "watchdog",
817 		.data           = &watchdog_user_enabled,
818 		.maxlen         = sizeof (int),
819 		.mode           = 0644,
820 		.proc_handler   = proc_dowatchdog,
821 		.extra1		= &zero,
822 		.extra2		= &one,
823 	},
824 	{
825 		.procname	= "watchdog_thresh",
826 		.data		= &watchdog_thresh,
827 		.maxlen		= sizeof(int),
828 		.mode		= 0644,
829 		.proc_handler	= proc_dowatchdog,
830 		.extra1		= &zero,
831 		.extra2		= &sixty,
832 	},
833 	{
834 		.procname	= "softlockup_panic",
835 		.data		= &softlockup_panic,
836 		.maxlen		= sizeof(int),
837 		.mode		= 0644,
838 		.proc_handler	= proc_dointvec_minmax,
839 		.extra1		= &zero,
840 		.extra2		= &one,
841 	},
842 	{
843 		.procname       = "nmi_watchdog",
844 		.data           = &watchdog_user_enabled,
845 		.maxlen         = sizeof (int),
846 		.mode           = 0644,
847 		.proc_handler   = proc_dowatchdog,
848 		.extra1		= &zero,
849 		.extra2		= &one,
850 	},
851 #endif
852 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
853 	{
854 		.procname       = "unknown_nmi_panic",
855 		.data           = &unknown_nmi_panic,
856 		.maxlen         = sizeof (int),
857 		.mode           = 0644,
858 		.proc_handler   = proc_dointvec,
859 	},
860 #endif
861 #if defined(CONFIG_X86)
862 	{
863 		.procname	= "panic_on_unrecovered_nmi",
864 		.data		= &panic_on_unrecovered_nmi,
865 		.maxlen		= sizeof(int),
866 		.mode		= 0644,
867 		.proc_handler	= proc_dointvec,
868 	},
869 	{
870 		.procname	= "panic_on_io_nmi",
871 		.data		= &panic_on_io_nmi,
872 		.maxlen		= sizeof(int),
873 		.mode		= 0644,
874 		.proc_handler	= proc_dointvec,
875 	},
876 #ifdef CONFIG_DEBUG_STACKOVERFLOW
877 	{
878 		.procname	= "panic_on_stackoverflow",
879 		.data		= &sysctl_panic_on_stackoverflow,
880 		.maxlen		= sizeof(int),
881 		.mode		= 0644,
882 		.proc_handler	= proc_dointvec,
883 	},
884 #endif
885 	{
886 		.procname	= "bootloader_type",
887 		.data		= &bootloader_type,
888 		.maxlen		= sizeof (int),
889 		.mode		= 0444,
890 		.proc_handler	= proc_dointvec,
891 	},
892 	{
893 		.procname	= "bootloader_version",
894 		.data		= &bootloader_version,
895 		.maxlen		= sizeof (int),
896 		.mode		= 0444,
897 		.proc_handler	= proc_dointvec,
898 	},
899 	{
900 		.procname	= "kstack_depth_to_print",
901 		.data		= &kstack_depth_to_print,
902 		.maxlen		= sizeof(int),
903 		.mode		= 0644,
904 		.proc_handler	= proc_dointvec,
905 	},
906 	{
907 		.procname	= "io_delay_type",
908 		.data		= &io_delay_type,
909 		.maxlen		= sizeof(int),
910 		.mode		= 0644,
911 		.proc_handler	= proc_dointvec,
912 	},
913 #endif
914 #if defined(CONFIG_MMU)
915 	{
916 		.procname	= "randomize_va_space",
917 		.data		= &randomize_va_space,
918 		.maxlen		= sizeof(int),
919 		.mode		= 0644,
920 		.proc_handler	= proc_dointvec,
921 	},
922 #endif
923 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
924 	{
925 		.procname	= "spin_retry",
926 		.data		= &spin_retry,
927 		.maxlen		= sizeof (int),
928 		.mode		= 0644,
929 		.proc_handler	= proc_dointvec,
930 	},
931 #endif
932 #if	defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
933 	{
934 		.procname	= "acpi_video_flags",
935 		.data		= &acpi_realmode_flags,
936 		.maxlen		= sizeof (unsigned long),
937 		.mode		= 0644,
938 		.proc_handler	= proc_doulongvec_minmax,
939 	},
940 #endif
941 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
942 	{
943 		.procname	= "ignore-unaligned-usertrap",
944 		.data		= &no_unaligned_warning,
945 		.maxlen		= sizeof (int),
946 	 	.mode		= 0644,
947 		.proc_handler	= proc_dointvec,
948 	},
949 #endif
950 #ifdef CONFIG_IA64
951 	{
952 		.procname	= "unaligned-dump-stack",
953 		.data		= &unaligned_dump_stack,
954 		.maxlen		= sizeof (int),
955 		.mode		= 0644,
956 		.proc_handler	= proc_dointvec,
957 	},
958 #endif
959 #ifdef CONFIG_DETECT_HUNG_TASK
960 	{
961 		.procname	= "hung_task_panic",
962 		.data		= &sysctl_hung_task_panic,
963 		.maxlen		= sizeof(int),
964 		.mode		= 0644,
965 		.proc_handler	= proc_dointvec_minmax,
966 		.extra1		= &zero,
967 		.extra2		= &one,
968 	},
969 	{
970 		.procname	= "hung_task_check_count",
971 		.data		= &sysctl_hung_task_check_count,
972 		.maxlen		= sizeof(int),
973 		.mode		= 0644,
974 		.proc_handler	= proc_dointvec_minmax,
975 		.extra1		= &zero,
976 	},
977 	{
978 		.procname	= "hung_task_timeout_secs",
979 		.data		= &sysctl_hung_task_timeout_secs,
980 		.maxlen		= sizeof(unsigned long),
981 		.mode		= 0644,
982 		.proc_handler	= proc_dohung_task_timeout_secs,
983 	},
984 	{
985 		.procname	= "hung_task_warnings",
986 		.data		= &sysctl_hung_task_warnings,
987 		.maxlen		= sizeof(unsigned long),
988 		.mode		= 0644,
989 		.proc_handler	= proc_doulongvec_minmax,
990 	},
991 #endif
992 #ifdef CONFIG_COMPAT
993 	{
994 		.procname	= "compat-log",
995 		.data		= &compat_log,
996 		.maxlen		= sizeof (int),
997 	 	.mode		= 0644,
998 		.proc_handler	= proc_dointvec,
999 	},
1000 #endif
1001 #ifdef CONFIG_RT_MUTEXES
1002 	{
1003 		.procname	= "max_lock_depth",
1004 		.data		= &max_lock_depth,
1005 		.maxlen		= sizeof(int),
1006 		.mode		= 0644,
1007 		.proc_handler	= proc_dointvec,
1008 	},
1009 #endif
1010 	{
1011 		.procname	= "poweroff_cmd",
1012 		.data		= &poweroff_cmd,
1013 		.maxlen		= POWEROFF_CMD_PATH_LEN,
1014 		.mode		= 0644,
1015 		.proc_handler	= proc_dostring,
1016 	},
1017 #ifdef CONFIG_KEYS
1018 	{
1019 		.procname	= "keys",
1020 		.mode		= 0555,
1021 		.child		= key_sysctls,
1022 	},
1023 #endif
1024 #ifdef CONFIG_RCU_TORTURE_TEST
1025 	{
1026 		.procname       = "rcutorture_runnable",
1027 		.data           = &rcutorture_runnable,
1028 		.maxlen         = sizeof(int),
1029 		.mode           = 0644,
1030 		.proc_handler	= proc_dointvec,
1031 	},
1032 #endif
1033 #ifdef CONFIG_PERF_EVENTS
1034 	/*
1035 	 * User-space scripts rely on the existence of this file
1036 	 * as a feature check for perf_events being enabled.
1037 	 *
1038 	 * So it's an ABI, do not remove!
1039 	 */
1040 	{
1041 		.procname	= "perf_event_paranoid",
1042 		.data		= &sysctl_perf_event_paranoid,
1043 		.maxlen		= sizeof(sysctl_perf_event_paranoid),
1044 		.mode		= 0644,
1045 		.proc_handler	= proc_dointvec,
1046 	},
1047 	{
1048 		.procname	= "perf_event_mlock_kb",
1049 		.data		= &sysctl_perf_event_mlock,
1050 		.maxlen		= sizeof(sysctl_perf_event_mlock),
1051 		.mode		= 0644,
1052 		.proc_handler	= proc_dointvec,
1053 	},
1054 	{
1055 		.procname	= "perf_event_max_sample_rate",
1056 		.data		= &sysctl_perf_event_sample_rate,
1057 		.maxlen		= sizeof(sysctl_perf_event_sample_rate),
1058 		.mode		= 0644,
1059 		.proc_handler	= perf_proc_update_handler,
1060 		.extra1		= &one,
1061 	},
1062 	{
1063 		.procname	= "perf_cpu_time_max_percent",
1064 		.data		= &sysctl_perf_cpu_time_max_percent,
1065 		.maxlen		= sizeof(sysctl_perf_cpu_time_max_percent),
1066 		.mode		= 0644,
1067 		.proc_handler	= perf_cpu_time_max_percent_handler,
1068 		.extra1		= &zero,
1069 		.extra2		= &one_hundred,
1070 	},
1071 #endif
1072 #ifdef CONFIG_KMEMCHECK
1073 	{
1074 		.procname	= "kmemcheck",
1075 		.data		= &kmemcheck_enabled,
1076 		.maxlen		= sizeof(int),
1077 		.mode		= 0644,
1078 		.proc_handler	= proc_dointvec,
1079 	},
1080 #endif
1081 #ifdef CONFIG_BLOCK
1082 	{
1083 		.procname	= "blk_iopoll",
1084 		.data		= &blk_iopoll_enabled,
1085 		.maxlen		= sizeof(int),
1086 		.mode		= 0644,
1087 		.proc_handler	= proc_dointvec,
1088 	},
1089 #endif
1090 	{ }
1091 };
1092 
1093 static struct ctl_table vm_table[] = {
1094 	{
1095 		.procname	= "overcommit_memory",
1096 		.data		= &sysctl_overcommit_memory,
1097 		.maxlen		= sizeof(sysctl_overcommit_memory),
1098 		.mode		= 0644,
1099 		.proc_handler	= proc_dointvec_minmax,
1100 		.extra1		= &zero,
1101 		.extra2		= &two,
1102 	},
1103 	{
1104 		.procname	= "panic_on_oom",
1105 		.data		= &sysctl_panic_on_oom,
1106 		.maxlen		= sizeof(sysctl_panic_on_oom),
1107 		.mode		= 0644,
1108 		.proc_handler	= proc_dointvec_minmax,
1109 		.extra1		= &zero,
1110 		.extra2		= &two,
1111 	},
1112 	{
1113 		.procname	= "oom_kill_allocating_task",
1114 		.data		= &sysctl_oom_kill_allocating_task,
1115 		.maxlen		= sizeof(sysctl_oom_kill_allocating_task),
1116 		.mode		= 0644,
1117 		.proc_handler	= proc_dointvec,
1118 	},
1119 	{
1120 		.procname	= "oom_dump_tasks",
1121 		.data		= &sysctl_oom_dump_tasks,
1122 		.maxlen		= sizeof(sysctl_oom_dump_tasks),
1123 		.mode		= 0644,
1124 		.proc_handler	= proc_dointvec,
1125 	},
1126 	{
1127 		.procname	= "overcommit_ratio",
1128 		.data		= &sysctl_overcommit_ratio,
1129 		.maxlen		= sizeof(sysctl_overcommit_ratio),
1130 		.mode		= 0644,
1131 		.proc_handler	= overcommit_ratio_handler,
1132 	},
1133 	{
1134 		.procname	= "overcommit_kbytes",
1135 		.data		= &sysctl_overcommit_kbytes,
1136 		.maxlen		= sizeof(sysctl_overcommit_kbytes),
1137 		.mode		= 0644,
1138 		.proc_handler	= overcommit_kbytes_handler,
1139 	},
1140 	{
1141 		.procname	= "page-cluster",
1142 		.data		= &page_cluster,
1143 		.maxlen		= sizeof(int),
1144 		.mode		= 0644,
1145 		.proc_handler	= proc_dointvec_minmax,
1146 		.extra1		= &zero,
1147 	},
1148 	{
1149 		.procname	= "dirty_background_ratio",
1150 		.data		= &dirty_background_ratio,
1151 		.maxlen		= sizeof(dirty_background_ratio),
1152 		.mode		= 0644,
1153 		.proc_handler	= dirty_background_ratio_handler,
1154 		.extra1		= &zero,
1155 		.extra2		= &one_hundred,
1156 	},
1157 	{
1158 		.procname	= "dirty_background_bytes",
1159 		.data		= &dirty_background_bytes,
1160 		.maxlen		= sizeof(dirty_background_bytes),
1161 		.mode		= 0644,
1162 		.proc_handler	= dirty_background_bytes_handler,
1163 		.extra1		= &one_ul,
1164 	},
1165 	{
1166 		.procname	= "dirty_ratio",
1167 		.data		= &vm_dirty_ratio,
1168 		.maxlen		= sizeof(vm_dirty_ratio),
1169 		.mode		= 0644,
1170 		.proc_handler	= dirty_ratio_handler,
1171 		.extra1		= &zero,
1172 		.extra2		= &one_hundred,
1173 	},
1174 	{
1175 		.procname	= "dirty_bytes",
1176 		.data		= &vm_dirty_bytes,
1177 		.maxlen		= sizeof(vm_dirty_bytes),
1178 		.mode		= 0644,
1179 		.proc_handler	= dirty_bytes_handler,
1180 		.extra1		= &dirty_bytes_min,
1181 	},
1182 	{
1183 		.procname	= "dirty_writeback_centisecs",
1184 		.data		= &dirty_writeback_interval,
1185 		.maxlen		= sizeof(dirty_writeback_interval),
1186 		.mode		= 0644,
1187 		.proc_handler	= dirty_writeback_centisecs_handler,
1188 	},
1189 	{
1190 		.procname	= "dirty_expire_centisecs",
1191 		.data		= &dirty_expire_interval,
1192 		.maxlen		= sizeof(dirty_expire_interval),
1193 		.mode		= 0644,
1194 		.proc_handler	= proc_dointvec_minmax,
1195 		.extra1		= &zero,
1196 	},
1197 	{
1198 		.procname       = "nr_pdflush_threads",
1199 		.mode           = 0444 /* read-only */,
1200 		.proc_handler   = pdflush_proc_obsolete,
1201 	},
1202 	{
1203 		.procname	= "swappiness",
1204 		.data		= &vm_swappiness,
1205 		.maxlen		= sizeof(vm_swappiness),
1206 		.mode		= 0644,
1207 		.proc_handler	= proc_dointvec_minmax,
1208 		.extra1		= &zero,
1209 		.extra2		= &one_hundred,
1210 	},
1211 #ifdef CONFIG_HUGETLB_PAGE
1212 	{
1213 		.procname	= "nr_hugepages",
1214 		.data		= NULL,
1215 		.maxlen		= sizeof(unsigned long),
1216 		.mode		= 0644,
1217 		.proc_handler	= hugetlb_sysctl_handler,
1218 		.extra1		= (void *)&hugetlb_zero,
1219 		.extra2		= (void *)&hugetlb_infinity,
1220 	},
1221 #ifdef CONFIG_NUMA
1222 	{
1223 		.procname       = "nr_hugepages_mempolicy",
1224 		.data           = NULL,
1225 		.maxlen         = sizeof(unsigned long),
1226 		.mode           = 0644,
1227 		.proc_handler   = &hugetlb_mempolicy_sysctl_handler,
1228 		.extra1		= (void *)&hugetlb_zero,
1229 		.extra2		= (void *)&hugetlb_infinity,
1230 	},
1231 #endif
1232 	 {
1233 		.procname	= "hugetlb_shm_group",
1234 		.data		= &sysctl_hugetlb_shm_group,
1235 		.maxlen		= sizeof(gid_t),
1236 		.mode		= 0644,
1237 		.proc_handler	= proc_dointvec,
1238 	 },
1239 	 {
1240 		.procname	= "hugepages_treat_as_movable",
1241 		.data		= &hugepages_treat_as_movable,
1242 		.maxlen		= sizeof(int),
1243 		.mode		= 0644,
1244 		.proc_handler	= proc_dointvec,
1245 	},
1246 	{
1247 		.procname	= "nr_overcommit_hugepages",
1248 		.data		= NULL,
1249 		.maxlen		= sizeof(unsigned long),
1250 		.mode		= 0644,
1251 		.proc_handler	= hugetlb_overcommit_handler,
1252 		.extra1		= (void *)&hugetlb_zero,
1253 		.extra2		= (void *)&hugetlb_infinity,
1254 	},
1255 #endif
1256 	{
1257 		.procname	= "lowmem_reserve_ratio",
1258 		.data		= &sysctl_lowmem_reserve_ratio,
1259 		.maxlen		= sizeof(sysctl_lowmem_reserve_ratio),
1260 		.mode		= 0644,
1261 		.proc_handler	= lowmem_reserve_ratio_sysctl_handler,
1262 	},
1263 	{
1264 		.procname	= "drop_caches",
1265 		.data		= &sysctl_drop_caches,
1266 		.maxlen		= sizeof(int),
1267 		.mode		= 0644,
1268 		.proc_handler	= drop_caches_sysctl_handler,
1269 		.extra1		= &one,
1270 		.extra2		= &three,
1271 	},
1272 #ifdef CONFIG_COMPACTION
1273 	{
1274 		.procname	= "compact_memory",
1275 		.data		= &sysctl_compact_memory,
1276 		.maxlen		= sizeof(int),
1277 		.mode		= 0200,
1278 		.proc_handler	= sysctl_compaction_handler,
1279 	},
1280 	{
1281 		.procname	= "extfrag_threshold",
1282 		.data		= &sysctl_extfrag_threshold,
1283 		.maxlen		= sizeof(int),
1284 		.mode		= 0644,
1285 		.proc_handler	= sysctl_extfrag_handler,
1286 		.extra1		= &min_extfrag_threshold,
1287 		.extra2		= &max_extfrag_threshold,
1288 	},
1289 
1290 #endif /* CONFIG_COMPACTION */
1291 	{
1292 		.procname	= "min_free_kbytes",
1293 		.data		= &min_free_kbytes,
1294 		.maxlen		= sizeof(min_free_kbytes),
1295 		.mode		= 0644,
1296 		.proc_handler	= min_free_kbytes_sysctl_handler,
1297 		.extra1		= &zero,
1298 	},
1299 	{
1300 		.procname	= "percpu_pagelist_fraction",
1301 		.data		= &percpu_pagelist_fraction,
1302 		.maxlen		= sizeof(percpu_pagelist_fraction),
1303 		.mode		= 0644,
1304 		.proc_handler	= percpu_pagelist_fraction_sysctl_handler,
1305 		.extra1		= &min_percpu_pagelist_fract,
1306 	},
1307 #ifdef CONFIG_MMU
1308 	{
1309 		.procname	= "max_map_count",
1310 		.data		= &sysctl_max_map_count,
1311 		.maxlen		= sizeof(sysctl_max_map_count),
1312 		.mode		= 0644,
1313 		.proc_handler	= proc_dointvec_minmax,
1314 		.extra1		= &zero,
1315 	},
1316 #else
1317 	{
1318 		.procname	= "nr_trim_pages",
1319 		.data		= &sysctl_nr_trim_pages,
1320 		.maxlen		= sizeof(sysctl_nr_trim_pages),
1321 		.mode		= 0644,
1322 		.proc_handler	= proc_dointvec_minmax,
1323 		.extra1		= &zero,
1324 	},
1325 #endif
1326 	{
1327 		.procname	= "laptop_mode",
1328 		.data		= &laptop_mode,
1329 		.maxlen		= sizeof(laptop_mode),
1330 		.mode		= 0644,
1331 		.proc_handler	= proc_dointvec_jiffies,
1332 	},
1333 	{
1334 		.procname	= "block_dump",
1335 		.data		= &block_dump,
1336 		.maxlen		= sizeof(block_dump),
1337 		.mode		= 0644,
1338 		.proc_handler	= proc_dointvec,
1339 		.extra1		= &zero,
1340 	},
1341 	{
1342 		.procname	= "vfs_cache_pressure",
1343 		.data		= &sysctl_vfs_cache_pressure,
1344 		.maxlen		= sizeof(sysctl_vfs_cache_pressure),
1345 		.mode		= 0644,
1346 		.proc_handler	= proc_dointvec,
1347 		.extra1		= &zero,
1348 	},
1349 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1350 	{
1351 		.procname	= "legacy_va_layout",
1352 		.data		= &sysctl_legacy_va_layout,
1353 		.maxlen		= sizeof(sysctl_legacy_va_layout),
1354 		.mode		= 0644,
1355 		.proc_handler	= proc_dointvec,
1356 		.extra1		= &zero,
1357 	},
1358 #endif
1359 #ifdef CONFIG_NUMA
1360 	{
1361 		.procname	= "zone_reclaim_mode",
1362 		.data		= &zone_reclaim_mode,
1363 		.maxlen		= sizeof(zone_reclaim_mode),
1364 		.mode		= 0644,
1365 		.proc_handler	= proc_dointvec,
1366 		.extra1		= &zero,
1367 	},
1368 	{
1369 		.procname	= "min_unmapped_ratio",
1370 		.data		= &sysctl_min_unmapped_ratio,
1371 		.maxlen		= sizeof(sysctl_min_unmapped_ratio),
1372 		.mode		= 0644,
1373 		.proc_handler	= sysctl_min_unmapped_ratio_sysctl_handler,
1374 		.extra1		= &zero,
1375 		.extra2		= &one_hundred,
1376 	},
1377 	{
1378 		.procname	= "min_slab_ratio",
1379 		.data		= &sysctl_min_slab_ratio,
1380 		.maxlen		= sizeof(sysctl_min_slab_ratio),
1381 		.mode		= 0644,
1382 		.proc_handler	= sysctl_min_slab_ratio_sysctl_handler,
1383 		.extra1		= &zero,
1384 		.extra2		= &one_hundred,
1385 	},
1386 #endif
1387 #ifdef CONFIG_SMP
1388 	{
1389 		.procname	= "stat_interval",
1390 		.data		= &sysctl_stat_interval,
1391 		.maxlen		= sizeof(sysctl_stat_interval),
1392 		.mode		= 0644,
1393 		.proc_handler	= proc_dointvec_jiffies,
1394 	},
1395 #endif
1396 #ifdef CONFIG_MMU
1397 	{
1398 		.procname	= "mmap_min_addr",
1399 		.data		= &dac_mmap_min_addr,
1400 		.maxlen		= sizeof(unsigned long),
1401 		.mode		= 0644,
1402 		.proc_handler	= mmap_min_addr_handler,
1403 	},
1404 #endif
1405 #ifdef CONFIG_NUMA
1406 	{
1407 		.procname	= "numa_zonelist_order",
1408 		.data		= &numa_zonelist_order,
1409 		.maxlen		= NUMA_ZONELIST_ORDER_LEN,
1410 		.mode		= 0644,
1411 		.proc_handler	= numa_zonelist_order_handler,
1412 	},
1413 #endif
1414 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1415    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1416 	{
1417 		.procname	= "vdso_enabled",
1418 		.data		= &vdso_enabled,
1419 		.maxlen		= sizeof(vdso_enabled),
1420 		.mode		= 0644,
1421 		.proc_handler	= proc_dointvec,
1422 		.extra1		= &zero,
1423 	},
1424 #endif
1425 #ifdef CONFIG_HIGHMEM
1426 	{
1427 		.procname	= "highmem_is_dirtyable",
1428 		.data		= &vm_highmem_is_dirtyable,
1429 		.maxlen		= sizeof(vm_highmem_is_dirtyable),
1430 		.mode		= 0644,
1431 		.proc_handler	= proc_dointvec_minmax,
1432 		.extra1		= &zero,
1433 		.extra2		= &one,
1434 	},
1435 #endif
1436 	{
1437 		.procname	= "scan_unevictable_pages",
1438 		.data		= &scan_unevictable_pages,
1439 		.maxlen		= sizeof(scan_unevictable_pages),
1440 		.mode		= 0644,
1441 		.proc_handler	= scan_unevictable_handler,
1442 	},
1443 #ifdef CONFIG_MEMORY_FAILURE
1444 	{
1445 		.procname	= "memory_failure_early_kill",
1446 		.data		= &sysctl_memory_failure_early_kill,
1447 		.maxlen		= sizeof(sysctl_memory_failure_early_kill),
1448 		.mode		= 0644,
1449 		.proc_handler	= proc_dointvec_minmax,
1450 		.extra1		= &zero,
1451 		.extra2		= &one,
1452 	},
1453 	{
1454 		.procname	= "memory_failure_recovery",
1455 		.data		= &sysctl_memory_failure_recovery,
1456 		.maxlen		= sizeof(sysctl_memory_failure_recovery),
1457 		.mode		= 0644,
1458 		.proc_handler	= proc_dointvec_minmax,
1459 		.extra1		= &zero,
1460 		.extra2		= &one,
1461 	},
1462 #endif
1463 	{
1464 		.procname	= "user_reserve_kbytes",
1465 		.data		= &sysctl_user_reserve_kbytes,
1466 		.maxlen		= sizeof(sysctl_user_reserve_kbytes),
1467 		.mode		= 0644,
1468 		.proc_handler	= proc_doulongvec_minmax,
1469 	},
1470 	{
1471 		.procname	= "admin_reserve_kbytes",
1472 		.data		= &sysctl_admin_reserve_kbytes,
1473 		.maxlen		= sizeof(sysctl_admin_reserve_kbytes),
1474 		.mode		= 0644,
1475 		.proc_handler	= proc_doulongvec_minmax,
1476 	},
1477 	{ }
1478 };
1479 
1480 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1481 static struct ctl_table binfmt_misc_table[] = {
1482 	{ }
1483 };
1484 #endif
1485 
1486 static struct ctl_table fs_table[] = {
1487 	{
1488 		.procname	= "inode-nr",
1489 		.data		= &inodes_stat,
1490 		.maxlen		= 2*sizeof(long),
1491 		.mode		= 0444,
1492 		.proc_handler	= proc_nr_inodes,
1493 	},
1494 	{
1495 		.procname	= "inode-state",
1496 		.data		= &inodes_stat,
1497 		.maxlen		= 7*sizeof(long),
1498 		.mode		= 0444,
1499 		.proc_handler	= proc_nr_inodes,
1500 	},
1501 	{
1502 		.procname	= "file-nr",
1503 		.data		= &files_stat,
1504 		.maxlen		= sizeof(files_stat),
1505 		.mode		= 0444,
1506 		.proc_handler	= proc_nr_files,
1507 	},
1508 	{
1509 		.procname	= "file-max",
1510 		.data		= &files_stat.max_files,
1511 		.maxlen		= sizeof(files_stat.max_files),
1512 		.mode		= 0644,
1513 		.proc_handler	= proc_doulongvec_minmax,
1514 	},
1515 	{
1516 		.procname	= "nr_open",
1517 		.data		= &sysctl_nr_open,
1518 		.maxlen		= sizeof(int),
1519 		.mode		= 0644,
1520 		.proc_handler	= proc_dointvec_minmax,
1521 		.extra1		= &sysctl_nr_open_min,
1522 		.extra2		= &sysctl_nr_open_max,
1523 	},
1524 	{
1525 		.procname	= "dentry-state",
1526 		.data		= &dentry_stat,
1527 		.maxlen		= 6*sizeof(long),
1528 		.mode		= 0444,
1529 		.proc_handler	= proc_nr_dentry,
1530 	},
1531 	{
1532 		.procname	= "overflowuid",
1533 		.data		= &fs_overflowuid,
1534 		.maxlen		= sizeof(int),
1535 		.mode		= 0644,
1536 		.proc_handler	= proc_dointvec_minmax,
1537 		.extra1		= &minolduid,
1538 		.extra2		= &maxolduid,
1539 	},
1540 	{
1541 		.procname	= "overflowgid",
1542 		.data		= &fs_overflowgid,
1543 		.maxlen		= sizeof(int),
1544 		.mode		= 0644,
1545 		.proc_handler	= proc_dointvec_minmax,
1546 		.extra1		= &minolduid,
1547 		.extra2		= &maxolduid,
1548 	},
1549 #ifdef CONFIG_FILE_LOCKING
1550 	{
1551 		.procname	= "leases-enable",
1552 		.data		= &leases_enable,
1553 		.maxlen		= sizeof(int),
1554 		.mode		= 0644,
1555 		.proc_handler	= proc_dointvec,
1556 	},
1557 #endif
1558 #ifdef CONFIG_DNOTIFY
1559 	{
1560 		.procname	= "dir-notify-enable",
1561 		.data		= &dir_notify_enable,
1562 		.maxlen		= sizeof(int),
1563 		.mode		= 0644,
1564 		.proc_handler	= proc_dointvec,
1565 	},
1566 #endif
1567 #ifdef CONFIG_MMU
1568 #ifdef CONFIG_FILE_LOCKING
1569 	{
1570 		.procname	= "lease-break-time",
1571 		.data		= &lease_break_time,
1572 		.maxlen		= sizeof(int),
1573 		.mode		= 0644,
1574 		.proc_handler	= proc_dointvec,
1575 	},
1576 #endif
1577 #ifdef CONFIG_AIO
1578 	{
1579 		.procname	= "aio-nr",
1580 		.data		= &aio_nr,
1581 		.maxlen		= sizeof(aio_nr),
1582 		.mode		= 0444,
1583 		.proc_handler	= proc_doulongvec_minmax,
1584 	},
1585 	{
1586 		.procname	= "aio-max-nr",
1587 		.data		= &aio_max_nr,
1588 		.maxlen		= sizeof(aio_max_nr),
1589 		.mode		= 0644,
1590 		.proc_handler	= proc_doulongvec_minmax,
1591 	},
1592 #endif /* CONFIG_AIO */
1593 #ifdef CONFIG_INOTIFY_USER
1594 	{
1595 		.procname	= "inotify",
1596 		.mode		= 0555,
1597 		.child		= inotify_table,
1598 	},
1599 #endif
1600 #ifdef CONFIG_EPOLL
1601 	{
1602 		.procname	= "epoll",
1603 		.mode		= 0555,
1604 		.child		= epoll_table,
1605 	},
1606 #endif
1607 #endif
1608 	{
1609 		.procname	= "protected_symlinks",
1610 		.data		= &sysctl_protected_symlinks,
1611 		.maxlen		= sizeof(int),
1612 		.mode		= 0600,
1613 		.proc_handler	= proc_dointvec_minmax,
1614 		.extra1		= &zero,
1615 		.extra2		= &one,
1616 	},
1617 	{
1618 		.procname	= "protected_hardlinks",
1619 		.data		= &sysctl_protected_hardlinks,
1620 		.maxlen		= sizeof(int),
1621 		.mode		= 0600,
1622 		.proc_handler	= proc_dointvec_minmax,
1623 		.extra1		= &zero,
1624 		.extra2		= &one,
1625 	},
1626 	{
1627 		.procname	= "suid_dumpable",
1628 		.data		= &suid_dumpable,
1629 		.maxlen		= sizeof(int),
1630 		.mode		= 0644,
1631 		.proc_handler	= proc_dointvec_minmax_coredump,
1632 		.extra1		= &zero,
1633 		.extra2		= &two,
1634 	},
1635 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1636 	{
1637 		.procname	= "binfmt_misc",
1638 		.mode		= 0555,
1639 		.child		= binfmt_misc_table,
1640 	},
1641 #endif
1642 	{
1643 		.procname	= "pipe-max-size",
1644 		.data		= &pipe_max_size,
1645 		.maxlen		= sizeof(int),
1646 		.mode		= 0644,
1647 		.proc_handler	= &pipe_proc_fn,
1648 		.extra1		= &pipe_min_size,
1649 	},
1650 	{ }
1651 };
1652 
1653 static struct ctl_table debug_table[] = {
1654 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1655 	{
1656 		.procname	= "exception-trace",
1657 		.data		= &show_unhandled_signals,
1658 		.maxlen		= sizeof(int),
1659 		.mode		= 0644,
1660 		.proc_handler	= proc_dointvec
1661 	},
1662 #endif
1663 #if defined(CONFIG_OPTPROBES)
1664 	{
1665 		.procname	= "kprobes-optimization",
1666 		.data		= &sysctl_kprobes_optimization,
1667 		.maxlen		= sizeof(int),
1668 		.mode		= 0644,
1669 		.proc_handler	= proc_kprobes_optimization_handler,
1670 		.extra1		= &zero,
1671 		.extra2		= &one,
1672 	},
1673 #endif
1674 	{ }
1675 };
1676 
1677 static struct ctl_table dev_table[] = {
1678 	{ }
1679 };
1680 
1681 int __init sysctl_init(void)
1682 {
1683 	struct ctl_table_header *hdr;
1684 
1685 	hdr = register_sysctl_table(sysctl_base_table);
1686 	kmemleak_not_leak(hdr);
1687 	return 0;
1688 }
1689 
1690 #endif /* CONFIG_SYSCTL */
1691 
1692 /*
1693  * /proc/sys support
1694  */
1695 
1696 #ifdef CONFIG_PROC_SYSCTL
1697 
1698 static int _proc_do_string(void* data, int maxlen, int write,
1699 			   void __user *buffer,
1700 			   size_t *lenp, loff_t *ppos)
1701 {
1702 	size_t len;
1703 	char __user *p;
1704 	char c;
1705 
1706 	if (!data || !maxlen || !*lenp) {
1707 		*lenp = 0;
1708 		return 0;
1709 	}
1710 
1711 	if (write) {
1712 		len = 0;
1713 		p = buffer;
1714 		while (len < *lenp) {
1715 			if (get_user(c, p++))
1716 				return -EFAULT;
1717 			if (c == 0 || c == '\n')
1718 				break;
1719 			len++;
1720 		}
1721 		if (len >= maxlen)
1722 			len = maxlen-1;
1723 		if(copy_from_user(data, buffer, len))
1724 			return -EFAULT;
1725 		((char *) data)[len] = 0;
1726 		*ppos += *lenp;
1727 	} else {
1728 		len = strlen(data);
1729 		if (len > maxlen)
1730 			len = maxlen;
1731 
1732 		if (*ppos > len) {
1733 			*lenp = 0;
1734 			return 0;
1735 		}
1736 
1737 		data += *ppos;
1738 		len  -= *ppos;
1739 
1740 		if (len > *lenp)
1741 			len = *lenp;
1742 		if (len)
1743 			if(copy_to_user(buffer, data, len))
1744 				return -EFAULT;
1745 		if (len < *lenp) {
1746 			if(put_user('\n', ((char __user *) buffer) + len))
1747 				return -EFAULT;
1748 			len++;
1749 		}
1750 		*lenp = len;
1751 		*ppos += len;
1752 	}
1753 	return 0;
1754 }
1755 
1756 /**
1757  * proc_dostring - read a string sysctl
1758  * @table: the sysctl table
1759  * @write: %TRUE if this is a write to the sysctl file
1760  * @buffer: the user buffer
1761  * @lenp: the size of the user buffer
1762  * @ppos: file position
1763  *
1764  * Reads/writes a string from/to the user buffer. If the kernel
1765  * buffer provided is not large enough to hold the string, the
1766  * string is truncated. The copied string is %NULL-terminated.
1767  * If the string is being read by the user process, it is copied
1768  * and a newline '\n' is added. It is truncated if the buffer is
1769  * not large enough.
1770  *
1771  * Returns 0 on success.
1772  */
1773 int proc_dostring(struct ctl_table *table, int write,
1774 		  void __user *buffer, size_t *lenp, loff_t *ppos)
1775 {
1776 	return _proc_do_string(table->data, table->maxlen, write,
1777 			       buffer, lenp, ppos);
1778 }
1779 
1780 static size_t proc_skip_spaces(char **buf)
1781 {
1782 	size_t ret;
1783 	char *tmp = skip_spaces(*buf);
1784 	ret = tmp - *buf;
1785 	*buf = tmp;
1786 	return ret;
1787 }
1788 
1789 static void proc_skip_char(char **buf, size_t *size, const char v)
1790 {
1791 	while (*size) {
1792 		if (**buf != v)
1793 			break;
1794 		(*size)--;
1795 		(*buf)++;
1796 	}
1797 }
1798 
1799 #define TMPBUFLEN 22
1800 /**
1801  * proc_get_long - reads an ASCII formatted integer from a user buffer
1802  *
1803  * @buf: a kernel buffer
1804  * @size: size of the kernel buffer
1805  * @val: this is where the number will be stored
1806  * @neg: set to %TRUE if number is negative
1807  * @perm_tr: a vector which contains the allowed trailers
1808  * @perm_tr_len: size of the perm_tr vector
1809  * @tr: pointer to store the trailer character
1810  *
1811  * In case of success %0 is returned and @buf and @size are updated with
1812  * the amount of bytes read. If @tr is non-NULL and a trailing
1813  * character exists (size is non-zero after returning from this
1814  * function), @tr is updated with the trailing character.
1815  */
1816 static int proc_get_long(char **buf, size_t *size,
1817 			  unsigned long *val, bool *neg,
1818 			  const char *perm_tr, unsigned perm_tr_len, char *tr)
1819 {
1820 	int len;
1821 	char *p, tmp[TMPBUFLEN];
1822 
1823 	if (!*size)
1824 		return -EINVAL;
1825 
1826 	len = *size;
1827 	if (len > TMPBUFLEN - 1)
1828 		len = TMPBUFLEN - 1;
1829 
1830 	memcpy(tmp, *buf, len);
1831 
1832 	tmp[len] = 0;
1833 	p = tmp;
1834 	if (*p == '-' && *size > 1) {
1835 		*neg = true;
1836 		p++;
1837 	} else
1838 		*neg = false;
1839 	if (!isdigit(*p))
1840 		return -EINVAL;
1841 
1842 	*val = simple_strtoul(p, &p, 0);
1843 
1844 	len = p - tmp;
1845 
1846 	/* We don't know if the next char is whitespace thus we may accept
1847 	 * invalid integers (e.g. 1234...a) or two integers instead of one
1848 	 * (e.g. 123...1). So lets not allow such large numbers. */
1849 	if (len == TMPBUFLEN - 1)
1850 		return -EINVAL;
1851 
1852 	if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
1853 		return -EINVAL;
1854 
1855 	if (tr && (len < *size))
1856 		*tr = *p;
1857 
1858 	*buf += len;
1859 	*size -= len;
1860 
1861 	return 0;
1862 }
1863 
1864 /**
1865  * proc_put_long - converts an integer to a decimal ASCII formatted string
1866  *
1867  * @buf: the user buffer
1868  * @size: the size of the user buffer
1869  * @val: the integer to be converted
1870  * @neg: sign of the number, %TRUE for negative
1871  *
1872  * In case of success %0 is returned and @buf and @size are updated with
1873  * the amount of bytes written.
1874  */
1875 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
1876 			  bool neg)
1877 {
1878 	int len;
1879 	char tmp[TMPBUFLEN], *p = tmp;
1880 
1881 	sprintf(p, "%s%lu", neg ? "-" : "", val);
1882 	len = strlen(tmp);
1883 	if (len > *size)
1884 		len = *size;
1885 	if (copy_to_user(*buf, tmp, len))
1886 		return -EFAULT;
1887 	*size -= len;
1888 	*buf += len;
1889 	return 0;
1890 }
1891 #undef TMPBUFLEN
1892 
1893 static int proc_put_char(void __user **buf, size_t *size, char c)
1894 {
1895 	if (*size) {
1896 		char __user **buffer = (char __user **)buf;
1897 		if (put_user(c, *buffer))
1898 			return -EFAULT;
1899 		(*size)--, (*buffer)++;
1900 		*buf = *buffer;
1901 	}
1902 	return 0;
1903 }
1904 
1905 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
1906 				 int *valp,
1907 				 int write, void *data)
1908 {
1909 	if (write) {
1910 		*valp = *negp ? -*lvalp : *lvalp;
1911 	} else {
1912 		int val = *valp;
1913 		if (val < 0) {
1914 			*negp = true;
1915 			*lvalp = (unsigned long)-val;
1916 		} else {
1917 			*negp = false;
1918 			*lvalp = (unsigned long)val;
1919 		}
1920 	}
1921 	return 0;
1922 }
1923 
1924 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
1925 
1926 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
1927 		  int write, void __user *buffer,
1928 		  size_t *lenp, loff_t *ppos,
1929 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
1930 			      int write, void *data),
1931 		  void *data)
1932 {
1933 	int *i, vleft, first = 1, err = 0;
1934 	unsigned long page = 0;
1935 	size_t left;
1936 	char *kbuf;
1937 
1938 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
1939 		*lenp = 0;
1940 		return 0;
1941 	}
1942 
1943 	i = (int *) tbl_data;
1944 	vleft = table->maxlen / sizeof(*i);
1945 	left = *lenp;
1946 
1947 	if (!conv)
1948 		conv = do_proc_dointvec_conv;
1949 
1950 	if (write) {
1951 		if (left > PAGE_SIZE - 1)
1952 			left = PAGE_SIZE - 1;
1953 		page = __get_free_page(GFP_TEMPORARY);
1954 		kbuf = (char *) page;
1955 		if (!kbuf)
1956 			return -ENOMEM;
1957 		if (copy_from_user(kbuf, buffer, left)) {
1958 			err = -EFAULT;
1959 			goto free;
1960 		}
1961 		kbuf[left] = 0;
1962 	}
1963 
1964 	for (; left && vleft--; i++, first=0) {
1965 		unsigned long lval;
1966 		bool neg;
1967 
1968 		if (write) {
1969 			left -= proc_skip_spaces(&kbuf);
1970 
1971 			if (!left)
1972 				break;
1973 			err = proc_get_long(&kbuf, &left, &lval, &neg,
1974 					     proc_wspace_sep,
1975 					     sizeof(proc_wspace_sep), NULL);
1976 			if (err)
1977 				break;
1978 			if (conv(&neg, &lval, i, 1, data)) {
1979 				err = -EINVAL;
1980 				break;
1981 			}
1982 		} else {
1983 			if (conv(&neg, &lval, i, 0, data)) {
1984 				err = -EINVAL;
1985 				break;
1986 			}
1987 			if (!first)
1988 				err = proc_put_char(&buffer, &left, '\t');
1989 			if (err)
1990 				break;
1991 			err = proc_put_long(&buffer, &left, lval, neg);
1992 			if (err)
1993 				break;
1994 		}
1995 	}
1996 
1997 	if (!write && !first && left && !err)
1998 		err = proc_put_char(&buffer, &left, '\n');
1999 	if (write && !err && left)
2000 		left -= proc_skip_spaces(&kbuf);
2001 free:
2002 	if (write) {
2003 		free_page(page);
2004 		if (first)
2005 			return err ? : -EINVAL;
2006 	}
2007 	*lenp -= left;
2008 	*ppos += *lenp;
2009 	return err;
2010 }
2011 
2012 static int do_proc_dointvec(struct ctl_table *table, int write,
2013 		  void __user *buffer, size_t *lenp, loff_t *ppos,
2014 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2015 			      int write, void *data),
2016 		  void *data)
2017 {
2018 	return __do_proc_dointvec(table->data, table, write,
2019 			buffer, lenp, ppos, conv, data);
2020 }
2021 
2022 /**
2023  * proc_dointvec - read a vector of integers
2024  * @table: the sysctl table
2025  * @write: %TRUE if this is a write to the sysctl file
2026  * @buffer: the user buffer
2027  * @lenp: the size of the user buffer
2028  * @ppos: file position
2029  *
2030  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2031  * values from/to the user buffer, treated as an ASCII string.
2032  *
2033  * Returns 0 on success.
2034  */
2035 int proc_dointvec(struct ctl_table *table, int write,
2036 		     void __user *buffer, size_t *lenp, loff_t *ppos)
2037 {
2038     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2039 		    	    NULL,NULL);
2040 }
2041 
2042 /*
2043  * Taint values can only be increased
2044  * This means we can safely use a temporary.
2045  */
2046 static int proc_taint(struct ctl_table *table, int write,
2047 			       void __user *buffer, size_t *lenp, loff_t *ppos)
2048 {
2049 	struct ctl_table t;
2050 	unsigned long tmptaint = get_taint();
2051 	int err;
2052 
2053 	if (write && !capable(CAP_SYS_ADMIN))
2054 		return -EPERM;
2055 
2056 	t = *table;
2057 	t.data = &tmptaint;
2058 	err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2059 	if (err < 0)
2060 		return err;
2061 
2062 	if (write) {
2063 		/*
2064 		 * Poor man's atomic or. Not worth adding a primitive
2065 		 * to everyone's atomic.h for this
2066 		 */
2067 		int i;
2068 		for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2069 			if ((tmptaint >> i) & 1)
2070 				add_taint(i, LOCKDEP_STILL_OK);
2071 		}
2072 	}
2073 
2074 	return err;
2075 }
2076 
2077 #ifdef CONFIG_PRINTK
2078 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2079 				void __user *buffer, size_t *lenp, loff_t *ppos)
2080 {
2081 	if (write && !capable(CAP_SYS_ADMIN))
2082 		return -EPERM;
2083 
2084 	return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2085 }
2086 #endif
2087 
2088 struct do_proc_dointvec_minmax_conv_param {
2089 	int *min;
2090 	int *max;
2091 };
2092 
2093 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2094 					int *valp,
2095 					int write, void *data)
2096 {
2097 	struct do_proc_dointvec_minmax_conv_param *param = data;
2098 	if (write) {
2099 		int val = *negp ? -*lvalp : *lvalp;
2100 		if ((param->min && *param->min > val) ||
2101 		    (param->max && *param->max < val))
2102 			return -EINVAL;
2103 		*valp = val;
2104 	} else {
2105 		int val = *valp;
2106 		if (val < 0) {
2107 			*negp = true;
2108 			*lvalp = (unsigned long)-val;
2109 		} else {
2110 			*negp = false;
2111 			*lvalp = (unsigned long)val;
2112 		}
2113 	}
2114 	return 0;
2115 }
2116 
2117 /**
2118  * proc_dointvec_minmax - read a vector of integers with min/max values
2119  * @table: the sysctl table
2120  * @write: %TRUE if this is a write to the sysctl file
2121  * @buffer: the user buffer
2122  * @lenp: the size of the user buffer
2123  * @ppos: file position
2124  *
2125  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2126  * values from/to the user buffer, treated as an ASCII string.
2127  *
2128  * This routine will ensure the values are within the range specified by
2129  * table->extra1 (min) and table->extra2 (max).
2130  *
2131  * Returns 0 on success.
2132  */
2133 int proc_dointvec_minmax(struct ctl_table *table, int write,
2134 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2135 {
2136 	struct do_proc_dointvec_minmax_conv_param param = {
2137 		.min = (int *) table->extra1,
2138 		.max = (int *) table->extra2,
2139 	};
2140 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
2141 				do_proc_dointvec_minmax_conv, &param);
2142 }
2143 
2144 static void validate_coredump_safety(void)
2145 {
2146 #ifdef CONFIG_COREDUMP
2147 	if (suid_dumpable == SUID_DUMP_ROOT &&
2148 	    core_pattern[0] != '/' && core_pattern[0] != '|') {
2149 		printk(KERN_WARNING "Unsafe core_pattern used with "\
2150 			"suid_dumpable=2. Pipe handler or fully qualified "\
2151 			"core dump path required.\n");
2152 	}
2153 #endif
2154 }
2155 
2156 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2157 		void __user *buffer, size_t *lenp, loff_t *ppos)
2158 {
2159 	int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2160 	if (!error)
2161 		validate_coredump_safety();
2162 	return error;
2163 }
2164 
2165 #ifdef CONFIG_COREDUMP
2166 static int proc_dostring_coredump(struct ctl_table *table, int write,
2167 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2168 {
2169 	int error = proc_dostring(table, write, buffer, lenp, ppos);
2170 	if (!error)
2171 		validate_coredump_safety();
2172 	return error;
2173 }
2174 #endif
2175 
2176 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2177 				     void __user *buffer,
2178 				     size_t *lenp, loff_t *ppos,
2179 				     unsigned long convmul,
2180 				     unsigned long convdiv)
2181 {
2182 	unsigned long *i, *min, *max;
2183 	int vleft, first = 1, err = 0;
2184 	unsigned long page = 0;
2185 	size_t left;
2186 	char *kbuf;
2187 
2188 	if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2189 		*lenp = 0;
2190 		return 0;
2191 	}
2192 
2193 	i = (unsigned long *) data;
2194 	min = (unsigned long *) table->extra1;
2195 	max = (unsigned long *) table->extra2;
2196 	vleft = table->maxlen / sizeof(unsigned long);
2197 	left = *lenp;
2198 
2199 	if (write) {
2200 		if (left > PAGE_SIZE - 1)
2201 			left = PAGE_SIZE - 1;
2202 		page = __get_free_page(GFP_TEMPORARY);
2203 		kbuf = (char *) page;
2204 		if (!kbuf)
2205 			return -ENOMEM;
2206 		if (copy_from_user(kbuf, buffer, left)) {
2207 			err = -EFAULT;
2208 			goto free;
2209 		}
2210 		kbuf[left] = 0;
2211 	}
2212 
2213 	for (; left && vleft--; i++, first = 0) {
2214 		unsigned long val;
2215 
2216 		if (write) {
2217 			bool neg;
2218 
2219 			left -= proc_skip_spaces(&kbuf);
2220 
2221 			err = proc_get_long(&kbuf, &left, &val, &neg,
2222 					     proc_wspace_sep,
2223 					     sizeof(proc_wspace_sep), NULL);
2224 			if (err)
2225 				break;
2226 			if (neg)
2227 				continue;
2228 			if ((min && val < *min) || (max && val > *max))
2229 				continue;
2230 			*i = val;
2231 		} else {
2232 			val = convdiv * (*i) / convmul;
2233 			if (!first) {
2234 				err = proc_put_char(&buffer, &left, '\t');
2235 				if (err)
2236 					break;
2237 			}
2238 			err = proc_put_long(&buffer, &left, val, false);
2239 			if (err)
2240 				break;
2241 		}
2242 	}
2243 
2244 	if (!write && !first && left && !err)
2245 		err = proc_put_char(&buffer, &left, '\n');
2246 	if (write && !err)
2247 		left -= proc_skip_spaces(&kbuf);
2248 free:
2249 	if (write) {
2250 		free_page(page);
2251 		if (first)
2252 			return err ? : -EINVAL;
2253 	}
2254 	*lenp -= left;
2255 	*ppos += *lenp;
2256 	return err;
2257 }
2258 
2259 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2260 				     void __user *buffer,
2261 				     size_t *lenp, loff_t *ppos,
2262 				     unsigned long convmul,
2263 				     unsigned long convdiv)
2264 {
2265 	return __do_proc_doulongvec_minmax(table->data, table, write,
2266 			buffer, lenp, ppos, convmul, convdiv);
2267 }
2268 
2269 /**
2270  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2271  * @table: the sysctl table
2272  * @write: %TRUE if this is a write to the sysctl file
2273  * @buffer: the user buffer
2274  * @lenp: the size of the user buffer
2275  * @ppos: file position
2276  *
2277  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2278  * values from/to the user buffer, treated as an ASCII string.
2279  *
2280  * This routine will ensure the values are within the range specified by
2281  * table->extra1 (min) and table->extra2 (max).
2282  *
2283  * Returns 0 on success.
2284  */
2285 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2286 			   void __user *buffer, size_t *lenp, loff_t *ppos)
2287 {
2288     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2289 }
2290 
2291 /**
2292  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2293  * @table: the sysctl table
2294  * @write: %TRUE if this is a write to the sysctl file
2295  * @buffer: the user buffer
2296  * @lenp: the size of the user buffer
2297  * @ppos: file position
2298  *
2299  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2300  * values from/to the user buffer, treated as an ASCII string. The values
2301  * are treated as milliseconds, and converted to jiffies when they are stored.
2302  *
2303  * This routine will ensure the values are within the range specified by
2304  * table->extra1 (min) and table->extra2 (max).
2305  *
2306  * Returns 0 on success.
2307  */
2308 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2309 				      void __user *buffer,
2310 				      size_t *lenp, loff_t *ppos)
2311 {
2312     return do_proc_doulongvec_minmax(table, write, buffer,
2313 				     lenp, ppos, HZ, 1000l);
2314 }
2315 
2316 
2317 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2318 					 int *valp,
2319 					 int write, void *data)
2320 {
2321 	if (write) {
2322 		if (*lvalp > LONG_MAX / HZ)
2323 			return 1;
2324 		*valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2325 	} else {
2326 		int val = *valp;
2327 		unsigned long lval;
2328 		if (val < 0) {
2329 			*negp = true;
2330 			lval = (unsigned long)-val;
2331 		} else {
2332 			*negp = false;
2333 			lval = (unsigned long)val;
2334 		}
2335 		*lvalp = lval / HZ;
2336 	}
2337 	return 0;
2338 }
2339 
2340 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2341 						int *valp,
2342 						int write, void *data)
2343 {
2344 	if (write) {
2345 		if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2346 			return 1;
2347 		*valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2348 	} else {
2349 		int val = *valp;
2350 		unsigned long lval;
2351 		if (val < 0) {
2352 			*negp = true;
2353 			lval = (unsigned long)-val;
2354 		} else {
2355 			*negp = false;
2356 			lval = (unsigned long)val;
2357 		}
2358 		*lvalp = jiffies_to_clock_t(lval);
2359 	}
2360 	return 0;
2361 }
2362 
2363 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2364 					    int *valp,
2365 					    int write, void *data)
2366 {
2367 	if (write) {
2368 		unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2369 
2370 		if (jif > INT_MAX)
2371 			return 1;
2372 		*valp = (int)jif;
2373 	} else {
2374 		int val = *valp;
2375 		unsigned long lval;
2376 		if (val < 0) {
2377 			*negp = true;
2378 			lval = (unsigned long)-val;
2379 		} else {
2380 			*negp = false;
2381 			lval = (unsigned long)val;
2382 		}
2383 		*lvalp = jiffies_to_msecs(lval);
2384 	}
2385 	return 0;
2386 }
2387 
2388 /**
2389  * proc_dointvec_jiffies - read a vector of integers as seconds
2390  * @table: the sysctl table
2391  * @write: %TRUE if this is a write to the sysctl file
2392  * @buffer: the user buffer
2393  * @lenp: the size of the user buffer
2394  * @ppos: file position
2395  *
2396  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2397  * values from/to the user buffer, treated as an ASCII string.
2398  * The values read are assumed to be in seconds, and are converted into
2399  * jiffies.
2400  *
2401  * Returns 0 on success.
2402  */
2403 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2404 			  void __user *buffer, size_t *lenp, loff_t *ppos)
2405 {
2406     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2407 		    	    do_proc_dointvec_jiffies_conv,NULL);
2408 }
2409 
2410 /**
2411  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2412  * @table: the sysctl table
2413  * @write: %TRUE if this is a write to the sysctl file
2414  * @buffer: the user buffer
2415  * @lenp: the size of the user buffer
2416  * @ppos: pointer to the file position
2417  *
2418  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2419  * values from/to the user buffer, treated as an ASCII string.
2420  * The values read are assumed to be in 1/USER_HZ seconds, and
2421  * are converted into jiffies.
2422  *
2423  * Returns 0 on success.
2424  */
2425 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2426 				 void __user *buffer, size_t *lenp, loff_t *ppos)
2427 {
2428     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2429 		    	    do_proc_dointvec_userhz_jiffies_conv,NULL);
2430 }
2431 
2432 /**
2433  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2434  * @table: the sysctl table
2435  * @write: %TRUE if this is a write to the sysctl file
2436  * @buffer: the user buffer
2437  * @lenp: the size of the user buffer
2438  * @ppos: file position
2439  * @ppos: the current position in the file
2440  *
2441  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2442  * values from/to the user buffer, treated as an ASCII string.
2443  * The values read are assumed to be in 1/1000 seconds, and
2444  * are converted into jiffies.
2445  *
2446  * Returns 0 on success.
2447  */
2448 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2449 			     void __user *buffer, size_t *lenp, loff_t *ppos)
2450 {
2451 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
2452 				do_proc_dointvec_ms_jiffies_conv, NULL);
2453 }
2454 
2455 static int proc_do_cad_pid(struct ctl_table *table, int write,
2456 			   void __user *buffer, size_t *lenp, loff_t *ppos)
2457 {
2458 	struct pid *new_pid;
2459 	pid_t tmp;
2460 	int r;
2461 
2462 	tmp = pid_vnr(cad_pid);
2463 
2464 	r = __do_proc_dointvec(&tmp, table, write, buffer,
2465 			       lenp, ppos, NULL, NULL);
2466 	if (r || !write)
2467 		return r;
2468 
2469 	new_pid = find_get_pid(tmp);
2470 	if (!new_pid)
2471 		return -ESRCH;
2472 
2473 	put_pid(xchg(&cad_pid, new_pid));
2474 	return 0;
2475 }
2476 
2477 /**
2478  * proc_do_large_bitmap - read/write from/to a large bitmap
2479  * @table: the sysctl table
2480  * @write: %TRUE if this is a write to the sysctl file
2481  * @buffer: the user buffer
2482  * @lenp: the size of the user buffer
2483  * @ppos: file position
2484  *
2485  * The bitmap is stored at table->data and the bitmap length (in bits)
2486  * in table->maxlen.
2487  *
2488  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2489  * large bitmaps may be represented in a compact manner. Writing into
2490  * the file will clear the bitmap then update it with the given input.
2491  *
2492  * Returns 0 on success.
2493  */
2494 int proc_do_large_bitmap(struct ctl_table *table, int write,
2495 			 void __user *buffer, size_t *lenp, loff_t *ppos)
2496 {
2497 	int err = 0;
2498 	bool first = 1;
2499 	size_t left = *lenp;
2500 	unsigned long bitmap_len = table->maxlen;
2501 	unsigned long *bitmap = (unsigned long *) table->data;
2502 	unsigned long *tmp_bitmap = NULL;
2503 	char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2504 
2505 	if (!bitmap_len || !left || (*ppos && !write)) {
2506 		*lenp = 0;
2507 		return 0;
2508 	}
2509 
2510 	if (write) {
2511 		unsigned long page = 0;
2512 		char *kbuf;
2513 
2514 		if (left > PAGE_SIZE - 1)
2515 			left = PAGE_SIZE - 1;
2516 
2517 		page = __get_free_page(GFP_TEMPORARY);
2518 		kbuf = (char *) page;
2519 		if (!kbuf)
2520 			return -ENOMEM;
2521 		if (copy_from_user(kbuf, buffer, left)) {
2522 			free_page(page);
2523 			return -EFAULT;
2524                 }
2525 		kbuf[left] = 0;
2526 
2527 		tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
2528 				     GFP_KERNEL);
2529 		if (!tmp_bitmap) {
2530 			free_page(page);
2531 			return -ENOMEM;
2532 		}
2533 		proc_skip_char(&kbuf, &left, '\n');
2534 		while (!err && left) {
2535 			unsigned long val_a, val_b;
2536 			bool neg;
2537 
2538 			err = proc_get_long(&kbuf, &left, &val_a, &neg, tr_a,
2539 					     sizeof(tr_a), &c);
2540 			if (err)
2541 				break;
2542 			if (val_a >= bitmap_len || neg) {
2543 				err = -EINVAL;
2544 				break;
2545 			}
2546 
2547 			val_b = val_a;
2548 			if (left) {
2549 				kbuf++;
2550 				left--;
2551 			}
2552 
2553 			if (c == '-') {
2554 				err = proc_get_long(&kbuf, &left, &val_b,
2555 						     &neg, tr_b, sizeof(tr_b),
2556 						     &c);
2557 				if (err)
2558 					break;
2559 				if (val_b >= bitmap_len || neg ||
2560 				    val_a > val_b) {
2561 					err = -EINVAL;
2562 					break;
2563 				}
2564 				if (left) {
2565 					kbuf++;
2566 					left--;
2567 				}
2568 			}
2569 
2570 			bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
2571 			first = 0;
2572 			proc_skip_char(&kbuf, &left, '\n');
2573 		}
2574 		free_page(page);
2575 	} else {
2576 		unsigned long bit_a, bit_b = 0;
2577 
2578 		while (left) {
2579 			bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
2580 			if (bit_a >= bitmap_len)
2581 				break;
2582 			bit_b = find_next_zero_bit(bitmap, bitmap_len,
2583 						   bit_a + 1) - 1;
2584 
2585 			if (!first) {
2586 				err = proc_put_char(&buffer, &left, ',');
2587 				if (err)
2588 					break;
2589 			}
2590 			err = proc_put_long(&buffer, &left, bit_a, false);
2591 			if (err)
2592 				break;
2593 			if (bit_a != bit_b) {
2594 				err = proc_put_char(&buffer, &left, '-');
2595 				if (err)
2596 					break;
2597 				err = proc_put_long(&buffer, &left, bit_b, false);
2598 				if (err)
2599 					break;
2600 			}
2601 
2602 			first = 0; bit_b++;
2603 		}
2604 		if (!err)
2605 			err = proc_put_char(&buffer, &left, '\n');
2606 	}
2607 
2608 	if (!err) {
2609 		if (write) {
2610 			if (*ppos)
2611 				bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
2612 			else
2613 				bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
2614 		}
2615 		kfree(tmp_bitmap);
2616 		*lenp -= left;
2617 		*ppos += *lenp;
2618 		return 0;
2619 	} else {
2620 		kfree(tmp_bitmap);
2621 		return err;
2622 	}
2623 }
2624 
2625 #else /* CONFIG_PROC_SYSCTL */
2626 
2627 int proc_dostring(struct ctl_table *table, int write,
2628 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2629 {
2630 	return -ENOSYS;
2631 }
2632 
2633 int proc_dointvec(struct ctl_table *table, int write,
2634 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2635 {
2636 	return -ENOSYS;
2637 }
2638 
2639 int proc_dointvec_minmax(struct ctl_table *table, int write,
2640 		    void __user *buffer, size_t *lenp, loff_t *ppos)
2641 {
2642 	return -ENOSYS;
2643 }
2644 
2645 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2646 		    void __user *buffer, size_t *lenp, loff_t *ppos)
2647 {
2648 	return -ENOSYS;
2649 }
2650 
2651 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2652 		    void __user *buffer, size_t *lenp, loff_t *ppos)
2653 {
2654 	return -ENOSYS;
2655 }
2656 
2657 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2658 			     void __user *buffer, size_t *lenp, loff_t *ppos)
2659 {
2660 	return -ENOSYS;
2661 }
2662 
2663 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2664 		    void __user *buffer, size_t *lenp, loff_t *ppos)
2665 {
2666 	return -ENOSYS;
2667 }
2668 
2669 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2670 				      void __user *buffer,
2671 				      size_t *lenp, loff_t *ppos)
2672 {
2673     return -ENOSYS;
2674 }
2675 
2676 
2677 #endif /* CONFIG_PROC_SYSCTL */
2678 
2679 /*
2680  * No sense putting this after each symbol definition, twice,
2681  * exception granted :-)
2682  */
2683 EXPORT_SYMBOL(proc_dointvec);
2684 EXPORT_SYMBOL(proc_dointvec_jiffies);
2685 EXPORT_SYMBOL(proc_dointvec_minmax);
2686 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2687 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2688 EXPORT_SYMBOL(proc_dostring);
2689 EXPORT_SYMBOL(proc_doulongvec_minmax);
2690 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2691