xref: /linux-6.15/kernel/sysctl.c (revision 9263969a)
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/aio.h>
23 #include <linux/mm.h>
24 #include <linux/swap.h>
25 #include <linux/slab.h>
26 #include <linux/sysctl.h>
27 #include <linux/bitmap.h>
28 #include <linux/signal.h>
29 #include <linux/printk.h>
30 #include <linux/proc_fs.h>
31 #include <linux/security.h>
32 #include <linux/ctype.h>
33 #include <linux/kmemcheck.h>
34 #include <linux/kmemleak.h>
35 #include <linux/fs.h>
36 #include <linux/init.h>
37 #include <linux/kernel.h>
38 #include <linux/kobject.h>
39 #include <linux/net.h>
40 #include <linux/sysrq.h>
41 #include <linux/highuid.h>
42 #include <linux/writeback.h>
43 #include <linux/ratelimit.h>
44 #include <linux/compaction.h>
45 #include <linux/hugetlb.h>
46 #include <linux/initrd.h>
47 #include <linux/key.h>
48 #include <linux/times.h>
49 #include <linux/limits.h>
50 #include <linux/dcache.h>
51 #include <linux/dnotify.h>
52 #include <linux/syscalls.h>
53 #include <linux/vmstat.h>
54 #include <linux/nfs_fs.h>
55 #include <linux/acpi.h>
56 #include <linux/reboot.h>
57 #include <linux/ftrace.h>
58 #include <linux/perf_event.h>
59 #include <linux/kprobes.h>
60 #include <linux/pipe_fs_i.h>
61 #include <linux/oom.h>
62 #include <linux/kmod.h>
63 #include <linux/capability.h>
64 #include <linux/binfmts.h>
65 #include <linux/sched/sysctl.h>
66 #include <linux/sched/coredump.h>
67 #include <linux/kexec.h>
68 #include <linux/bpf.h>
69 #include <linux/mount.h>
70 
71 #include <linux/uaccess.h>
72 #include <asm/processor.h>
73 
74 #ifdef CONFIG_X86
75 #include <asm/nmi.h>
76 #include <asm/stacktrace.h>
77 #include <asm/io.h>
78 #endif
79 #ifdef CONFIG_SPARC
80 #include <asm/setup.h>
81 #endif
82 #ifdef CONFIG_BSD_PROCESS_ACCT
83 #include <linux/acct.h>
84 #endif
85 #ifdef CONFIG_RT_MUTEXES
86 #include <linux/rtmutex.h>
87 #endif
88 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
89 #include <linux/lockdep.h>
90 #endif
91 #ifdef CONFIG_CHR_DEV_SG
92 #include <scsi/sg.h>
93 #endif
94 
95 #ifdef CONFIG_LOCKUP_DETECTOR
96 #include <linux/nmi.h>
97 #endif
98 
99 #if defined(CONFIG_SYSCTL)
100 
101 /* External variables not in a header file. */
102 extern int suid_dumpable;
103 #ifdef CONFIG_COREDUMP
104 extern int core_uses_pid;
105 extern char core_pattern[];
106 extern unsigned int core_pipe_limit;
107 #endif
108 extern int pid_max;
109 extern int pid_max_min, pid_max_max;
110 extern int percpu_pagelist_fraction;
111 extern int latencytop_enabled;
112 extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
113 #ifndef CONFIG_MMU
114 extern int sysctl_nr_trim_pages;
115 #endif
116 
117 /* Constants used for minimum and  maximum */
118 #ifdef CONFIG_LOCKUP_DETECTOR
119 static int sixty = 60;
120 #endif
121 
122 static int __maybe_unused neg_one = -1;
123 
124 static int zero;
125 static int __maybe_unused one = 1;
126 static int __maybe_unused two = 2;
127 static int __maybe_unused four = 4;
128 static unsigned long one_ul = 1;
129 static int one_hundred = 100;
130 static int one_thousand = 1000;
131 #ifdef CONFIG_PRINTK
132 static int ten_thousand = 10000;
133 #endif
134 #ifdef CONFIG_PERF_EVENTS
135 static int six_hundred_forty_kb = 640 * 1024;
136 #endif
137 
138 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
139 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
140 
141 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
142 static int maxolduid = 65535;
143 static int minolduid;
144 
145 static int ngroups_max = NGROUPS_MAX;
146 static const int cap_last_cap = CAP_LAST_CAP;
147 
148 /*this is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs */
149 #ifdef CONFIG_DETECT_HUNG_TASK
150 static unsigned long hung_task_timeout_max = (LONG_MAX/HZ);
151 #endif
152 
153 #ifdef CONFIG_INOTIFY_USER
154 #include <linux/inotify.h>
155 #endif
156 #ifdef CONFIG_SPARC
157 #endif
158 
159 #ifdef __hppa__
160 extern int pwrsw_enabled;
161 #endif
162 
163 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
164 extern int unaligned_enabled;
165 #endif
166 
167 #ifdef CONFIG_IA64
168 extern int unaligned_dump_stack;
169 #endif
170 
171 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
172 extern int no_unaligned_warning;
173 #endif
174 
175 #ifdef CONFIG_PROC_SYSCTL
176 
177 /**
178  * enum sysctl_writes_mode - supported sysctl write modes
179  *
180  * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
181  * 	to be written, and multiple writes on the same sysctl file descriptor
182  * 	will rewrite the sysctl value, regardless of file position. No warning
183  * 	is issued when the initial position is not 0.
184  * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
185  * 	not 0.
186  * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
187  * 	file position 0 and the value must be fully contained in the buffer
188  * 	sent to the write syscall. If dealing with strings respect the file
189  * 	position, but restrict this to the max length of the buffer, anything
190  * 	passed the max lenght will be ignored. Multiple writes will append
191  * 	to the buffer.
192  *
193  * These write modes control how current file position affects the behavior of
194  * updating sysctl values through the proc interface on each write.
195  */
196 enum sysctl_writes_mode {
197 	SYSCTL_WRITES_LEGACY		= -1,
198 	SYSCTL_WRITES_WARN		= 0,
199 	SYSCTL_WRITES_STRICT		= 1,
200 };
201 
202 static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
203 
204 static int proc_do_cad_pid(struct ctl_table *table, int write,
205 		  void __user *buffer, size_t *lenp, loff_t *ppos);
206 static int proc_taint(struct ctl_table *table, int write,
207 			       void __user *buffer, size_t *lenp, loff_t *ppos);
208 #endif
209 
210 #ifdef CONFIG_PRINTK
211 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
212 				void __user *buffer, size_t *lenp, loff_t *ppos);
213 #endif
214 
215 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
216 		void __user *buffer, size_t *lenp, loff_t *ppos);
217 #ifdef CONFIG_COREDUMP
218 static int proc_dostring_coredump(struct ctl_table *table, int write,
219 		void __user *buffer, size_t *lenp, loff_t *ppos);
220 #endif
221 
222 #ifdef CONFIG_MAGIC_SYSRQ
223 /* Note: sysrq code uses it's own private copy */
224 static int __sysrq_enabled = CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE;
225 
226 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
227 				void __user *buffer, size_t *lenp,
228 				loff_t *ppos)
229 {
230 	int error;
231 
232 	error = proc_dointvec(table, write, buffer, lenp, ppos);
233 	if (error)
234 		return error;
235 
236 	if (write)
237 		sysrq_toggle_support(__sysrq_enabled);
238 
239 	return 0;
240 }
241 
242 #endif
243 
244 static struct ctl_table kern_table[];
245 static struct ctl_table vm_table[];
246 static struct ctl_table fs_table[];
247 static struct ctl_table debug_table[];
248 static struct ctl_table dev_table[];
249 extern struct ctl_table random_table[];
250 #ifdef CONFIG_EPOLL
251 extern struct ctl_table epoll_table[];
252 #endif
253 
254 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
255 int sysctl_legacy_va_layout;
256 #endif
257 
258 /* The default sysctl tables: */
259 
260 static struct ctl_table sysctl_base_table[] = {
261 	{
262 		.procname	= "kernel",
263 		.mode		= 0555,
264 		.child		= kern_table,
265 	},
266 	{
267 		.procname	= "vm",
268 		.mode		= 0555,
269 		.child		= vm_table,
270 	},
271 	{
272 		.procname	= "fs",
273 		.mode		= 0555,
274 		.child		= fs_table,
275 	},
276 	{
277 		.procname	= "debug",
278 		.mode		= 0555,
279 		.child		= debug_table,
280 	},
281 	{
282 		.procname	= "dev",
283 		.mode		= 0555,
284 		.child		= dev_table,
285 	},
286 	{ }
287 };
288 
289 #ifdef CONFIG_SCHED_DEBUG
290 static int min_sched_granularity_ns = 100000;		/* 100 usecs */
291 static int max_sched_granularity_ns = NSEC_PER_SEC;	/* 1 second */
292 static int min_wakeup_granularity_ns;			/* 0 usecs */
293 static int max_wakeup_granularity_ns = NSEC_PER_SEC;	/* 1 second */
294 #ifdef CONFIG_SMP
295 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
296 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
297 #endif /* CONFIG_SMP */
298 #endif /* CONFIG_SCHED_DEBUG */
299 
300 #ifdef CONFIG_COMPACTION
301 static int min_extfrag_threshold;
302 static int max_extfrag_threshold = 1000;
303 #endif
304 
305 static struct ctl_table kern_table[] = {
306 	{
307 		.procname	= "sched_child_runs_first",
308 		.data		= &sysctl_sched_child_runs_first,
309 		.maxlen		= sizeof(unsigned int),
310 		.mode		= 0644,
311 		.proc_handler	= proc_dointvec,
312 	},
313 #ifdef CONFIG_SCHED_DEBUG
314 	{
315 		.procname	= "sched_min_granularity_ns",
316 		.data		= &sysctl_sched_min_granularity,
317 		.maxlen		= sizeof(unsigned int),
318 		.mode		= 0644,
319 		.proc_handler	= sched_proc_update_handler,
320 		.extra1		= &min_sched_granularity_ns,
321 		.extra2		= &max_sched_granularity_ns,
322 	},
323 	{
324 		.procname	= "sched_latency_ns",
325 		.data		= &sysctl_sched_latency,
326 		.maxlen		= sizeof(unsigned int),
327 		.mode		= 0644,
328 		.proc_handler	= sched_proc_update_handler,
329 		.extra1		= &min_sched_granularity_ns,
330 		.extra2		= &max_sched_granularity_ns,
331 	},
332 	{
333 		.procname	= "sched_wakeup_granularity_ns",
334 		.data		= &sysctl_sched_wakeup_granularity,
335 		.maxlen		= sizeof(unsigned int),
336 		.mode		= 0644,
337 		.proc_handler	= sched_proc_update_handler,
338 		.extra1		= &min_wakeup_granularity_ns,
339 		.extra2		= &max_wakeup_granularity_ns,
340 	},
341 #ifdef CONFIG_SMP
342 	{
343 		.procname	= "sched_tunable_scaling",
344 		.data		= &sysctl_sched_tunable_scaling,
345 		.maxlen		= sizeof(enum sched_tunable_scaling),
346 		.mode		= 0644,
347 		.proc_handler	= sched_proc_update_handler,
348 		.extra1		= &min_sched_tunable_scaling,
349 		.extra2		= &max_sched_tunable_scaling,
350 	},
351 	{
352 		.procname	= "sched_migration_cost_ns",
353 		.data		= &sysctl_sched_migration_cost,
354 		.maxlen		= sizeof(unsigned int),
355 		.mode		= 0644,
356 		.proc_handler	= proc_dointvec,
357 	},
358 	{
359 		.procname	= "sched_nr_migrate",
360 		.data		= &sysctl_sched_nr_migrate,
361 		.maxlen		= sizeof(unsigned int),
362 		.mode		= 0644,
363 		.proc_handler	= proc_dointvec,
364 	},
365 	{
366 		.procname	= "sched_time_avg_ms",
367 		.data		= &sysctl_sched_time_avg,
368 		.maxlen		= sizeof(unsigned int),
369 		.mode		= 0644,
370 		.proc_handler	= proc_dointvec,
371 	},
372 #ifdef CONFIG_SCHEDSTATS
373 	{
374 		.procname	= "sched_schedstats",
375 		.data		= NULL,
376 		.maxlen		= sizeof(unsigned int),
377 		.mode		= 0644,
378 		.proc_handler	= sysctl_schedstats,
379 		.extra1		= &zero,
380 		.extra2		= &one,
381 	},
382 #endif /* CONFIG_SCHEDSTATS */
383 #endif /* CONFIG_SMP */
384 #ifdef CONFIG_NUMA_BALANCING
385 	{
386 		.procname	= "numa_balancing_scan_delay_ms",
387 		.data		= &sysctl_numa_balancing_scan_delay,
388 		.maxlen		= sizeof(unsigned int),
389 		.mode		= 0644,
390 		.proc_handler	= proc_dointvec,
391 	},
392 	{
393 		.procname	= "numa_balancing_scan_period_min_ms",
394 		.data		= &sysctl_numa_balancing_scan_period_min,
395 		.maxlen		= sizeof(unsigned int),
396 		.mode		= 0644,
397 		.proc_handler	= proc_dointvec,
398 	},
399 	{
400 		.procname	= "numa_balancing_scan_period_max_ms",
401 		.data		= &sysctl_numa_balancing_scan_period_max,
402 		.maxlen		= sizeof(unsigned int),
403 		.mode		= 0644,
404 		.proc_handler	= proc_dointvec,
405 	},
406 	{
407 		.procname	= "numa_balancing_scan_size_mb",
408 		.data		= &sysctl_numa_balancing_scan_size,
409 		.maxlen		= sizeof(unsigned int),
410 		.mode		= 0644,
411 		.proc_handler	= proc_dointvec_minmax,
412 		.extra1		= &one,
413 	},
414 	{
415 		.procname	= "numa_balancing",
416 		.data		= NULL, /* filled in by handler */
417 		.maxlen		= sizeof(unsigned int),
418 		.mode		= 0644,
419 		.proc_handler	= sysctl_numa_balancing,
420 		.extra1		= &zero,
421 		.extra2		= &one,
422 	},
423 #endif /* CONFIG_NUMA_BALANCING */
424 #endif /* CONFIG_SCHED_DEBUG */
425 	{
426 		.procname	= "sched_rt_period_us",
427 		.data		= &sysctl_sched_rt_period,
428 		.maxlen		= sizeof(unsigned int),
429 		.mode		= 0644,
430 		.proc_handler	= sched_rt_handler,
431 	},
432 	{
433 		.procname	= "sched_rt_runtime_us",
434 		.data		= &sysctl_sched_rt_runtime,
435 		.maxlen		= sizeof(int),
436 		.mode		= 0644,
437 		.proc_handler	= sched_rt_handler,
438 	},
439 	{
440 		.procname	= "sched_rr_timeslice_ms",
441 		.data		= &sysctl_sched_rr_timeslice,
442 		.maxlen		= sizeof(int),
443 		.mode		= 0644,
444 		.proc_handler	= sched_rr_handler,
445 	},
446 #ifdef CONFIG_SCHED_AUTOGROUP
447 	{
448 		.procname	= "sched_autogroup_enabled",
449 		.data		= &sysctl_sched_autogroup_enabled,
450 		.maxlen		= sizeof(unsigned int),
451 		.mode		= 0644,
452 		.proc_handler	= proc_dointvec_minmax,
453 		.extra1		= &zero,
454 		.extra2		= &one,
455 	},
456 #endif
457 #ifdef CONFIG_CFS_BANDWIDTH
458 	{
459 		.procname	= "sched_cfs_bandwidth_slice_us",
460 		.data		= &sysctl_sched_cfs_bandwidth_slice,
461 		.maxlen		= sizeof(unsigned int),
462 		.mode		= 0644,
463 		.proc_handler	= proc_dointvec_minmax,
464 		.extra1		= &one,
465 	},
466 #endif
467 #ifdef CONFIG_PROVE_LOCKING
468 	{
469 		.procname	= "prove_locking",
470 		.data		= &prove_locking,
471 		.maxlen		= sizeof(int),
472 		.mode		= 0644,
473 		.proc_handler	= proc_dointvec,
474 	},
475 #endif
476 #ifdef CONFIG_LOCK_STAT
477 	{
478 		.procname	= "lock_stat",
479 		.data		= &lock_stat,
480 		.maxlen		= sizeof(int),
481 		.mode		= 0644,
482 		.proc_handler	= proc_dointvec,
483 	},
484 #endif
485 	{
486 		.procname	= "panic",
487 		.data		= &panic_timeout,
488 		.maxlen		= sizeof(int),
489 		.mode		= 0644,
490 		.proc_handler	= proc_dointvec,
491 	},
492 #ifdef CONFIG_COREDUMP
493 	{
494 		.procname	= "core_uses_pid",
495 		.data		= &core_uses_pid,
496 		.maxlen		= sizeof(int),
497 		.mode		= 0644,
498 		.proc_handler	= proc_dointvec,
499 	},
500 	{
501 		.procname	= "core_pattern",
502 		.data		= core_pattern,
503 		.maxlen		= CORENAME_MAX_SIZE,
504 		.mode		= 0644,
505 		.proc_handler	= proc_dostring_coredump,
506 	},
507 	{
508 		.procname	= "core_pipe_limit",
509 		.data		= &core_pipe_limit,
510 		.maxlen		= sizeof(unsigned int),
511 		.mode		= 0644,
512 		.proc_handler	= proc_dointvec,
513 	},
514 #endif
515 #ifdef CONFIG_PROC_SYSCTL
516 	{
517 		.procname	= "tainted",
518 		.maxlen 	= sizeof(long),
519 		.mode		= 0644,
520 		.proc_handler	= proc_taint,
521 	},
522 	{
523 		.procname	= "sysctl_writes_strict",
524 		.data		= &sysctl_writes_strict,
525 		.maxlen		= sizeof(int),
526 		.mode		= 0644,
527 		.proc_handler	= proc_dointvec_minmax,
528 		.extra1		= &neg_one,
529 		.extra2		= &one,
530 	},
531 #endif
532 #ifdef CONFIG_LATENCYTOP
533 	{
534 		.procname	= "latencytop",
535 		.data		= &latencytop_enabled,
536 		.maxlen		= sizeof(int),
537 		.mode		= 0644,
538 		.proc_handler	= sysctl_latencytop,
539 	},
540 #endif
541 #ifdef CONFIG_BLK_DEV_INITRD
542 	{
543 		.procname	= "real-root-dev",
544 		.data		= &real_root_dev,
545 		.maxlen		= sizeof(int),
546 		.mode		= 0644,
547 		.proc_handler	= proc_dointvec,
548 	},
549 #endif
550 	{
551 		.procname	= "print-fatal-signals",
552 		.data		= &print_fatal_signals,
553 		.maxlen		= sizeof(int),
554 		.mode		= 0644,
555 		.proc_handler	= proc_dointvec,
556 	},
557 #ifdef CONFIG_SPARC
558 	{
559 		.procname	= "reboot-cmd",
560 		.data		= reboot_command,
561 		.maxlen		= 256,
562 		.mode		= 0644,
563 		.proc_handler	= proc_dostring,
564 	},
565 	{
566 		.procname	= "stop-a",
567 		.data		= &stop_a_enabled,
568 		.maxlen		= sizeof (int),
569 		.mode		= 0644,
570 		.proc_handler	= proc_dointvec,
571 	},
572 	{
573 		.procname	= "scons-poweroff",
574 		.data		= &scons_pwroff,
575 		.maxlen		= sizeof (int),
576 		.mode		= 0644,
577 		.proc_handler	= proc_dointvec,
578 	},
579 #endif
580 #ifdef CONFIG_SPARC64
581 	{
582 		.procname	= "tsb-ratio",
583 		.data		= &sysctl_tsb_ratio,
584 		.maxlen		= sizeof (int),
585 		.mode		= 0644,
586 		.proc_handler	= proc_dointvec,
587 	},
588 #endif
589 #ifdef __hppa__
590 	{
591 		.procname	= "soft-power",
592 		.data		= &pwrsw_enabled,
593 		.maxlen		= sizeof (int),
594 	 	.mode		= 0644,
595 		.proc_handler	= proc_dointvec,
596 	},
597 #endif
598 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
599 	{
600 		.procname	= "unaligned-trap",
601 		.data		= &unaligned_enabled,
602 		.maxlen		= sizeof (int),
603 		.mode		= 0644,
604 		.proc_handler	= proc_dointvec,
605 	},
606 #endif
607 	{
608 		.procname	= "ctrl-alt-del",
609 		.data		= &C_A_D,
610 		.maxlen		= sizeof(int),
611 		.mode		= 0644,
612 		.proc_handler	= proc_dointvec,
613 	},
614 #ifdef CONFIG_FUNCTION_TRACER
615 	{
616 		.procname	= "ftrace_enabled",
617 		.data		= &ftrace_enabled,
618 		.maxlen		= sizeof(int),
619 		.mode		= 0644,
620 		.proc_handler	= ftrace_enable_sysctl,
621 	},
622 #endif
623 #ifdef CONFIG_STACK_TRACER
624 	{
625 		.procname	= "stack_tracer_enabled",
626 		.data		= &stack_tracer_enabled,
627 		.maxlen		= sizeof(int),
628 		.mode		= 0644,
629 		.proc_handler	= stack_trace_sysctl,
630 	},
631 #endif
632 #ifdef CONFIG_TRACING
633 	{
634 		.procname	= "ftrace_dump_on_oops",
635 		.data		= &ftrace_dump_on_oops,
636 		.maxlen		= sizeof(int),
637 		.mode		= 0644,
638 		.proc_handler	= proc_dointvec,
639 	},
640 	{
641 		.procname	= "traceoff_on_warning",
642 		.data		= &__disable_trace_on_warning,
643 		.maxlen		= sizeof(__disable_trace_on_warning),
644 		.mode		= 0644,
645 		.proc_handler	= proc_dointvec,
646 	},
647 	{
648 		.procname	= "tracepoint_printk",
649 		.data		= &tracepoint_printk,
650 		.maxlen		= sizeof(tracepoint_printk),
651 		.mode		= 0644,
652 		.proc_handler	= tracepoint_printk_sysctl,
653 	},
654 #endif
655 #ifdef CONFIG_KEXEC_CORE
656 	{
657 		.procname	= "kexec_load_disabled",
658 		.data		= &kexec_load_disabled,
659 		.maxlen		= sizeof(int),
660 		.mode		= 0644,
661 		/* only handle a transition from default "0" to "1" */
662 		.proc_handler	= proc_dointvec_minmax,
663 		.extra1		= &one,
664 		.extra2		= &one,
665 	},
666 #endif
667 #ifdef CONFIG_MODULES
668 	{
669 		.procname	= "modprobe",
670 		.data		= &modprobe_path,
671 		.maxlen		= KMOD_PATH_LEN,
672 		.mode		= 0644,
673 		.proc_handler	= proc_dostring,
674 	},
675 	{
676 		.procname	= "modules_disabled",
677 		.data		= &modules_disabled,
678 		.maxlen		= sizeof(int),
679 		.mode		= 0644,
680 		/* only handle a transition from default "0" to "1" */
681 		.proc_handler	= proc_dointvec_minmax,
682 		.extra1		= &one,
683 		.extra2		= &one,
684 	},
685 #endif
686 #ifdef CONFIG_UEVENT_HELPER
687 	{
688 		.procname	= "hotplug",
689 		.data		= &uevent_helper,
690 		.maxlen		= UEVENT_HELPER_PATH_LEN,
691 		.mode		= 0644,
692 		.proc_handler	= proc_dostring,
693 	},
694 #endif
695 #ifdef CONFIG_CHR_DEV_SG
696 	{
697 		.procname	= "sg-big-buff",
698 		.data		= &sg_big_buff,
699 		.maxlen		= sizeof (int),
700 		.mode		= 0444,
701 		.proc_handler	= proc_dointvec,
702 	},
703 #endif
704 #ifdef CONFIG_BSD_PROCESS_ACCT
705 	{
706 		.procname	= "acct",
707 		.data		= &acct_parm,
708 		.maxlen		= 3*sizeof(int),
709 		.mode		= 0644,
710 		.proc_handler	= proc_dointvec,
711 	},
712 #endif
713 #ifdef CONFIG_MAGIC_SYSRQ
714 	{
715 		.procname	= "sysrq",
716 		.data		= &__sysrq_enabled,
717 		.maxlen		= sizeof (int),
718 		.mode		= 0644,
719 		.proc_handler	= sysrq_sysctl_handler,
720 	},
721 #endif
722 #ifdef CONFIG_PROC_SYSCTL
723 	{
724 		.procname	= "cad_pid",
725 		.data		= NULL,
726 		.maxlen		= sizeof (int),
727 		.mode		= 0600,
728 		.proc_handler	= proc_do_cad_pid,
729 	},
730 #endif
731 	{
732 		.procname	= "threads-max",
733 		.data		= NULL,
734 		.maxlen		= sizeof(int),
735 		.mode		= 0644,
736 		.proc_handler	= sysctl_max_threads,
737 	},
738 	{
739 		.procname	= "random",
740 		.mode		= 0555,
741 		.child		= random_table,
742 	},
743 	{
744 		.procname	= "usermodehelper",
745 		.mode		= 0555,
746 		.child		= usermodehelper_table,
747 	},
748 	{
749 		.procname	= "overflowuid",
750 		.data		= &overflowuid,
751 		.maxlen		= sizeof(int),
752 		.mode		= 0644,
753 		.proc_handler	= proc_dointvec_minmax,
754 		.extra1		= &minolduid,
755 		.extra2		= &maxolduid,
756 	},
757 	{
758 		.procname	= "overflowgid",
759 		.data		= &overflowgid,
760 		.maxlen		= sizeof(int),
761 		.mode		= 0644,
762 		.proc_handler	= proc_dointvec_minmax,
763 		.extra1		= &minolduid,
764 		.extra2		= &maxolduid,
765 	},
766 #ifdef CONFIG_S390
767 #ifdef CONFIG_MATHEMU
768 	{
769 		.procname	= "ieee_emulation_warnings",
770 		.data		= &sysctl_ieee_emulation_warnings,
771 		.maxlen		= sizeof(int),
772 		.mode		= 0644,
773 		.proc_handler	= proc_dointvec,
774 	},
775 #endif
776 	{
777 		.procname	= "userprocess_debug",
778 		.data		= &show_unhandled_signals,
779 		.maxlen		= sizeof(int),
780 		.mode		= 0644,
781 		.proc_handler	= proc_dointvec,
782 	},
783 #endif
784 	{
785 		.procname	= "pid_max",
786 		.data		= &pid_max,
787 		.maxlen		= sizeof (int),
788 		.mode		= 0644,
789 		.proc_handler	= proc_dointvec_minmax,
790 		.extra1		= &pid_max_min,
791 		.extra2		= &pid_max_max,
792 	},
793 	{
794 		.procname	= "panic_on_oops",
795 		.data		= &panic_on_oops,
796 		.maxlen		= sizeof(int),
797 		.mode		= 0644,
798 		.proc_handler	= proc_dointvec,
799 	},
800 #if defined CONFIG_PRINTK
801 	{
802 		.procname	= "printk",
803 		.data		= &console_loglevel,
804 		.maxlen		= 4*sizeof(int),
805 		.mode		= 0644,
806 		.proc_handler	= proc_dointvec,
807 	},
808 	{
809 		.procname	= "printk_ratelimit",
810 		.data		= &printk_ratelimit_state.interval,
811 		.maxlen		= sizeof(int),
812 		.mode		= 0644,
813 		.proc_handler	= proc_dointvec_jiffies,
814 	},
815 	{
816 		.procname	= "printk_ratelimit_burst",
817 		.data		= &printk_ratelimit_state.burst,
818 		.maxlen		= sizeof(int),
819 		.mode		= 0644,
820 		.proc_handler	= proc_dointvec,
821 	},
822 	{
823 		.procname	= "printk_delay",
824 		.data		= &printk_delay_msec,
825 		.maxlen		= sizeof(int),
826 		.mode		= 0644,
827 		.proc_handler	= proc_dointvec_minmax,
828 		.extra1		= &zero,
829 		.extra2		= &ten_thousand,
830 	},
831 	{
832 		.procname	= "printk_devkmsg",
833 		.data		= devkmsg_log_str,
834 		.maxlen		= DEVKMSG_STR_MAX_SIZE,
835 		.mode		= 0644,
836 		.proc_handler	= devkmsg_sysctl_set_loglvl,
837 	},
838 	{
839 		.procname	= "dmesg_restrict",
840 		.data		= &dmesg_restrict,
841 		.maxlen		= sizeof(int),
842 		.mode		= 0644,
843 		.proc_handler	= proc_dointvec_minmax_sysadmin,
844 		.extra1		= &zero,
845 		.extra2		= &one,
846 	},
847 	{
848 		.procname	= "kptr_restrict",
849 		.data		= &kptr_restrict,
850 		.maxlen		= sizeof(int),
851 		.mode		= 0644,
852 		.proc_handler	= proc_dointvec_minmax_sysadmin,
853 		.extra1		= &zero,
854 		.extra2		= &two,
855 	},
856 #endif
857 	{
858 		.procname	= "ngroups_max",
859 		.data		= &ngroups_max,
860 		.maxlen		= sizeof (int),
861 		.mode		= 0444,
862 		.proc_handler	= proc_dointvec,
863 	},
864 	{
865 		.procname	= "cap_last_cap",
866 		.data		= (void *)&cap_last_cap,
867 		.maxlen		= sizeof(int),
868 		.mode		= 0444,
869 		.proc_handler	= proc_dointvec,
870 	},
871 #if defined(CONFIG_LOCKUP_DETECTOR)
872 	{
873 		.procname       = "watchdog",
874 		.data           = &watchdog_user_enabled,
875 		.maxlen         = sizeof (int),
876 		.mode           = 0644,
877 		.proc_handler   = proc_watchdog,
878 		.extra1		= &zero,
879 		.extra2		= &one,
880 	},
881 	{
882 		.procname	= "watchdog_thresh",
883 		.data		= &watchdog_thresh,
884 		.maxlen		= sizeof(int),
885 		.mode		= 0644,
886 		.proc_handler	= proc_watchdog_thresh,
887 		.extra1		= &zero,
888 		.extra2		= &sixty,
889 	},
890 	{
891 		.procname       = "nmi_watchdog",
892 		.data           = &nmi_watchdog_enabled,
893 		.maxlen         = sizeof (int),
894 		.mode           = 0644,
895 		.proc_handler   = proc_nmi_watchdog,
896 		.extra1		= &zero,
897 #if defined(CONFIG_HAVE_NMI_WATCHDOG) || defined(CONFIG_HARDLOCKUP_DETECTOR)
898 		.extra2		= &one,
899 #else
900 		.extra2		= &zero,
901 #endif
902 	},
903 	{
904 		.procname       = "soft_watchdog",
905 		.data           = &soft_watchdog_enabled,
906 		.maxlen         = sizeof (int),
907 		.mode           = 0644,
908 		.proc_handler   = proc_soft_watchdog,
909 		.extra1		= &zero,
910 		.extra2		= &one,
911 	},
912 	{
913 		.procname	= "watchdog_cpumask",
914 		.data		= &watchdog_cpumask_bits,
915 		.maxlen		= NR_CPUS,
916 		.mode		= 0644,
917 		.proc_handler	= proc_watchdog_cpumask,
918 	},
919 	{
920 		.procname	= "softlockup_panic",
921 		.data		= &softlockup_panic,
922 		.maxlen		= sizeof(int),
923 		.mode		= 0644,
924 		.proc_handler	= proc_dointvec_minmax,
925 		.extra1		= &zero,
926 		.extra2		= &one,
927 	},
928 #ifdef CONFIG_HARDLOCKUP_DETECTOR
929 	{
930 		.procname	= "hardlockup_panic",
931 		.data		= &hardlockup_panic,
932 		.maxlen		= sizeof(int),
933 		.mode		= 0644,
934 		.proc_handler	= proc_dointvec_minmax,
935 		.extra1		= &zero,
936 		.extra2		= &one,
937 	},
938 #endif
939 #ifdef CONFIG_SMP
940 	{
941 		.procname	= "softlockup_all_cpu_backtrace",
942 		.data		= &sysctl_softlockup_all_cpu_backtrace,
943 		.maxlen		= sizeof(int),
944 		.mode		= 0644,
945 		.proc_handler	= proc_dointvec_minmax,
946 		.extra1		= &zero,
947 		.extra2		= &one,
948 	},
949 	{
950 		.procname	= "hardlockup_all_cpu_backtrace",
951 		.data		= &sysctl_hardlockup_all_cpu_backtrace,
952 		.maxlen		= sizeof(int),
953 		.mode		= 0644,
954 		.proc_handler	= proc_dointvec_minmax,
955 		.extra1		= &zero,
956 		.extra2		= &one,
957 	},
958 #endif /* CONFIG_SMP */
959 #endif
960 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
961 	{
962 		.procname       = "unknown_nmi_panic",
963 		.data           = &unknown_nmi_panic,
964 		.maxlen         = sizeof (int),
965 		.mode           = 0644,
966 		.proc_handler   = proc_dointvec,
967 	},
968 #endif
969 #if defined(CONFIG_X86)
970 	{
971 		.procname	= "panic_on_unrecovered_nmi",
972 		.data		= &panic_on_unrecovered_nmi,
973 		.maxlen		= sizeof(int),
974 		.mode		= 0644,
975 		.proc_handler	= proc_dointvec,
976 	},
977 	{
978 		.procname	= "panic_on_io_nmi",
979 		.data		= &panic_on_io_nmi,
980 		.maxlen		= sizeof(int),
981 		.mode		= 0644,
982 		.proc_handler	= proc_dointvec,
983 	},
984 #ifdef CONFIG_DEBUG_STACKOVERFLOW
985 	{
986 		.procname	= "panic_on_stackoverflow",
987 		.data		= &sysctl_panic_on_stackoverflow,
988 		.maxlen		= sizeof(int),
989 		.mode		= 0644,
990 		.proc_handler	= proc_dointvec,
991 	},
992 #endif
993 	{
994 		.procname	= "bootloader_type",
995 		.data		= &bootloader_type,
996 		.maxlen		= sizeof (int),
997 		.mode		= 0444,
998 		.proc_handler	= proc_dointvec,
999 	},
1000 	{
1001 		.procname	= "bootloader_version",
1002 		.data		= &bootloader_version,
1003 		.maxlen		= sizeof (int),
1004 		.mode		= 0444,
1005 		.proc_handler	= proc_dointvec,
1006 	},
1007 	{
1008 		.procname	= "io_delay_type",
1009 		.data		= &io_delay_type,
1010 		.maxlen		= sizeof(int),
1011 		.mode		= 0644,
1012 		.proc_handler	= proc_dointvec,
1013 	},
1014 #endif
1015 #if defined(CONFIG_MMU)
1016 	{
1017 		.procname	= "randomize_va_space",
1018 		.data		= &randomize_va_space,
1019 		.maxlen		= sizeof(int),
1020 		.mode		= 0644,
1021 		.proc_handler	= proc_dointvec,
1022 	},
1023 #endif
1024 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1025 	{
1026 		.procname	= "spin_retry",
1027 		.data		= &spin_retry,
1028 		.maxlen		= sizeof (int),
1029 		.mode		= 0644,
1030 		.proc_handler	= proc_dointvec,
1031 	},
1032 #endif
1033 #if	defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1034 	{
1035 		.procname	= "acpi_video_flags",
1036 		.data		= &acpi_realmode_flags,
1037 		.maxlen		= sizeof (unsigned long),
1038 		.mode		= 0644,
1039 		.proc_handler	= proc_doulongvec_minmax,
1040 	},
1041 #endif
1042 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1043 	{
1044 		.procname	= "ignore-unaligned-usertrap",
1045 		.data		= &no_unaligned_warning,
1046 		.maxlen		= sizeof (int),
1047 	 	.mode		= 0644,
1048 		.proc_handler	= proc_dointvec,
1049 	},
1050 #endif
1051 #ifdef CONFIG_IA64
1052 	{
1053 		.procname	= "unaligned-dump-stack",
1054 		.data		= &unaligned_dump_stack,
1055 		.maxlen		= sizeof (int),
1056 		.mode		= 0644,
1057 		.proc_handler	= proc_dointvec,
1058 	},
1059 #endif
1060 #ifdef CONFIG_DETECT_HUNG_TASK
1061 	{
1062 		.procname	= "hung_task_panic",
1063 		.data		= &sysctl_hung_task_panic,
1064 		.maxlen		= sizeof(int),
1065 		.mode		= 0644,
1066 		.proc_handler	= proc_dointvec_minmax,
1067 		.extra1		= &zero,
1068 		.extra2		= &one,
1069 	},
1070 	{
1071 		.procname	= "hung_task_check_count",
1072 		.data		= &sysctl_hung_task_check_count,
1073 		.maxlen		= sizeof(int),
1074 		.mode		= 0644,
1075 		.proc_handler	= proc_dointvec_minmax,
1076 		.extra1		= &zero,
1077 	},
1078 	{
1079 		.procname	= "hung_task_timeout_secs",
1080 		.data		= &sysctl_hung_task_timeout_secs,
1081 		.maxlen		= sizeof(unsigned long),
1082 		.mode		= 0644,
1083 		.proc_handler	= proc_dohung_task_timeout_secs,
1084 		.extra2		= &hung_task_timeout_max,
1085 	},
1086 	{
1087 		.procname	= "hung_task_warnings",
1088 		.data		= &sysctl_hung_task_warnings,
1089 		.maxlen		= sizeof(int),
1090 		.mode		= 0644,
1091 		.proc_handler	= proc_dointvec_minmax,
1092 		.extra1		= &neg_one,
1093 	},
1094 #endif
1095 #ifdef CONFIG_RT_MUTEXES
1096 	{
1097 		.procname	= "max_lock_depth",
1098 		.data		= &max_lock_depth,
1099 		.maxlen		= sizeof(int),
1100 		.mode		= 0644,
1101 		.proc_handler	= proc_dointvec,
1102 	},
1103 #endif
1104 	{
1105 		.procname	= "poweroff_cmd",
1106 		.data		= &poweroff_cmd,
1107 		.maxlen		= POWEROFF_CMD_PATH_LEN,
1108 		.mode		= 0644,
1109 		.proc_handler	= proc_dostring,
1110 	},
1111 #ifdef CONFIG_KEYS
1112 	{
1113 		.procname	= "keys",
1114 		.mode		= 0555,
1115 		.child		= key_sysctls,
1116 	},
1117 #endif
1118 #ifdef CONFIG_PERF_EVENTS
1119 	/*
1120 	 * User-space scripts rely on the existence of this file
1121 	 * as a feature check for perf_events being enabled.
1122 	 *
1123 	 * So it's an ABI, do not remove!
1124 	 */
1125 	{
1126 		.procname	= "perf_event_paranoid",
1127 		.data		= &sysctl_perf_event_paranoid,
1128 		.maxlen		= sizeof(sysctl_perf_event_paranoid),
1129 		.mode		= 0644,
1130 		.proc_handler	= proc_dointvec,
1131 	},
1132 	{
1133 		.procname	= "perf_event_mlock_kb",
1134 		.data		= &sysctl_perf_event_mlock,
1135 		.maxlen		= sizeof(sysctl_perf_event_mlock),
1136 		.mode		= 0644,
1137 		.proc_handler	= proc_dointvec,
1138 	},
1139 	{
1140 		.procname	= "perf_event_max_sample_rate",
1141 		.data		= &sysctl_perf_event_sample_rate,
1142 		.maxlen		= sizeof(sysctl_perf_event_sample_rate),
1143 		.mode		= 0644,
1144 		.proc_handler	= perf_proc_update_handler,
1145 		.extra1		= &one,
1146 	},
1147 	{
1148 		.procname	= "perf_cpu_time_max_percent",
1149 		.data		= &sysctl_perf_cpu_time_max_percent,
1150 		.maxlen		= sizeof(sysctl_perf_cpu_time_max_percent),
1151 		.mode		= 0644,
1152 		.proc_handler	= perf_cpu_time_max_percent_handler,
1153 		.extra1		= &zero,
1154 		.extra2		= &one_hundred,
1155 	},
1156 	{
1157 		.procname	= "perf_event_max_stack",
1158 		.data		= &sysctl_perf_event_max_stack,
1159 		.maxlen		= sizeof(sysctl_perf_event_max_stack),
1160 		.mode		= 0644,
1161 		.proc_handler	= perf_event_max_stack_handler,
1162 		.extra1		= &zero,
1163 		.extra2		= &six_hundred_forty_kb,
1164 	},
1165 	{
1166 		.procname	= "perf_event_max_contexts_per_stack",
1167 		.data		= &sysctl_perf_event_max_contexts_per_stack,
1168 		.maxlen		= sizeof(sysctl_perf_event_max_contexts_per_stack),
1169 		.mode		= 0644,
1170 		.proc_handler	= perf_event_max_stack_handler,
1171 		.extra1		= &zero,
1172 		.extra2		= &one_thousand,
1173 	},
1174 #endif
1175 #ifdef CONFIG_KMEMCHECK
1176 	{
1177 		.procname	= "kmemcheck",
1178 		.data		= &kmemcheck_enabled,
1179 		.maxlen		= sizeof(int),
1180 		.mode		= 0644,
1181 		.proc_handler	= proc_dointvec,
1182 	},
1183 #endif
1184 	{
1185 		.procname	= "panic_on_warn",
1186 		.data		= &panic_on_warn,
1187 		.maxlen		= sizeof(int),
1188 		.mode		= 0644,
1189 		.proc_handler	= proc_dointvec_minmax,
1190 		.extra1		= &zero,
1191 		.extra2		= &one,
1192 	},
1193 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1194 	{
1195 		.procname	= "timer_migration",
1196 		.data		= &sysctl_timer_migration,
1197 		.maxlen		= sizeof(unsigned int),
1198 		.mode		= 0644,
1199 		.proc_handler	= timer_migration_handler,
1200 		.extra1		= &zero,
1201 		.extra2		= &one,
1202 	},
1203 #endif
1204 #ifdef CONFIG_BPF_SYSCALL
1205 	{
1206 		.procname	= "unprivileged_bpf_disabled",
1207 		.data		= &sysctl_unprivileged_bpf_disabled,
1208 		.maxlen		= sizeof(sysctl_unprivileged_bpf_disabled),
1209 		.mode		= 0644,
1210 		/* only handle a transition from default "0" to "1" */
1211 		.proc_handler	= proc_dointvec_minmax,
1212 		.extra1		= &one,
1213 		.extra2		= &one,
1214 	},
1215 #endif
1216 #if defined(CONFIG_TREE_RCU) || defined(CONFIG_PREEMPT_RCU)
1217 	{
1218 		.procname	= "panic_on_rcu_stall",
1219 		.data		= &sysctl_panic_on_rcu_stall,
1220 		.maxlen		= sizeof(sysctl_panic_on_rcu_stall),
1221 		.mode		= 0644,
1222 		.proc_handler	= proc_dointvec_minmax,
1223 		.extra1		= &zero,
1224 		.extra2		= &one,
1225 	},
1226 #endif
1227 	{ }
1228 };
1229 
1230 static struct ctl_table vm_table[] = {
1231 	{
1232 		.procname	= "overcommit_memory",
1233 		.data		= &sysctl_overcommit_memory,
1234 		.maxlen		= sizeof(sysctl_overcommit_memory),
1235 		.mode		= 0644,
1236 		.proc_handler	= proc_dointvec_minmax,
1237 		.extra1		= &zero,
1238 		.extra2		= &two,
1239 	},
1240 	{
1241 		.procname	= "panic_on_oom",
1242 		.data		= &sysctl_panic_on_oom,
1243 		.maxlen		= sizeof(sysctl_panic_on_oom),
1244 		.mode		= 0644,
1245 		.proc_handler	= proc_dointvec_minmax,
1246 		.extra1		= &zero,
1247 		.extra2		= &two,
1248 	},
1249 	{
1250 		.procname	= "oom_kill_allocating_task",
1251 		.data		= &sysctl_oom_kill_allocating_task,
1252 		.maxlen		= sizeof(sysctl_oom_kill_allocating_task),
1253 		.mode		= 0644,
1254 		.proc_handler	= proc_dointvec,
1255 	},
1256 	{
1257 		.procname	= "oom_dump_tasks",
1258 		.data		= &sysctl_oom_dump_tasks,
1259 		.maxlen		= sizeof(sysctl_oom_dump_tasks),
1260 		.mode		= 0644,
1261 		.proc_handler	= proc_dointvec,
1262 	},
1263 	{
1264 		.procname	= "overcommit_ratio",
1265 		.data		= &sysctl_overcommit_ratio,
1266 		.maxlen		= sizeof(sysctl_overcommit_ratio),
1267 		.mode		= 0644,
1268 		.proc_handler	= overcommit_ratio_handler,
1269 	},
1270 	{
1271 		.procname	= "overcommit_kbytes",
1272 		.data		= &sysctl_overcommit_kbytes,
1273 		.maxlen		= sizeof(sysctl_overcommit_kbytes),
1274 		.mode		= 0644,
1275 		.proc_handler	= overcommit_kbytes_handler,
1276 	},
1277 	{
1278 		.procname	= "page-cluster",
1279 		.data		= &page_cluster,
1280 		.maxlen		= sizeof(int),
1281 		.mode		= 0644,
1282 		.proc_handler	= proc_dointvec_minmax,
1283 		.extra1		= &zero,
1284 	},
1285 	{
1286 		.procname	= "dirty_background_ratio",
1287 		.data		= &dirty_background_ratio,
1288 		.maxlen		= sizeof(dirty_background_ratio),
1289 		.mode		= 0644,
1290 		.proc_handler	= dirty_background_ratio_handler,
1291 		.extra1		= &zero,
1292 		.extra2		= &one_hundred,
1293 	},
1294 	{
1295 		.procname	= "dirty_background_bytes",
1296 		.data		= &dirty_background_bytes,
1297 		.maxlen		= sizeof(dirty_background_bytes),
1298 		.mode		= 0644,
1299 		.proc_handler	= dirty_background_bytes_handler,
1300 		.extra1		= &one_ul,
1301 	},
1302 	{
1303 		.procname	= "dirty_ratio",
1304 		.data		= &vm_dirty_ratio,
1305 		.maxlen		= sizeof(vm_dirty_ratio),
1306 		.mode		= 0644,
1307 		.proc_handler	= dirty_ratio_handler,
1308 		.extra1		= &zero,
1309 		.extra2		= &one_hundred,
1310 	},
1311 	{
1312 		.procname	= "dirty_bytes",
1313 		.data		= &vm_dirty_bytes,
1314 		.maxlen		= sizeof(vm_dirty_bytes),
1315 		.mode		= 0644,
1316 		.proc_handler	= dirty_bytes_handler,
1317 		.extra1		= &dirty_bytes_min,
1318 	},
1319 	{
1320 		.procname	= "dirty_writeback_centisecs",
1321 		.data		= &dirty_writeback_interval,
1322 		.maxlen		= sizeof(dirty_writeback_interval),
1323 		.mode		= 0644,
1324 		.proc_handler	= dirty_writeback_centisecs_handler,
1325 	},
1326 	{
1327 		.procname	= "dirty_expire_centisecs",
1328 		.data		= &dirty_expire_interval,
1329 		.maxlen		= sizeof(dirty_expire_interval),
1330 		.mode		= 0644,
1331 		.proc_handler	= proc_dointvec_minmax,
1332 		.extra1		= &zero,
1333 	},
1334 	{
1335 		.procname	= "dirtytime_expire_seconds",
1336 		.data		= &dirtytime_expire_interval,
1337 		.maxlen		= sizeof(dirty_expire_interval),
1338 		.mode		= 0644,
1339 		.proc_handler	= dirtytime_interval_handler,
1340 		.extra1		= &zero,
1341 	},
1342 	{
1343 		.procname       = "nr_pdflush_threads",
1344 		.mode           = 0444 /* read-only */,
1345 		.proc_handler   = pdflush_proc_obsolete,
1346 	},
1347 	{
1348 		.procname	= "swappiness",
1349 		.data		= &vm_swappiness,
1350 		.maxlen		= sizeof(vm_swappiness),
1351 		.mode		= 0644,
1352 		.proc_handler	= proc_dointvec_minmax,
1353 		.extra1		= &zero,
1354 		.extra2		= &one_hundred,
1355 	},
1356 #ifdef CONFIG_HUGETLB_PAGE
1357 	{
1358 		.procname	= "nr_hugepages",
1359 		.data		= NULL,
1360 		.maxlen		= sizeof(unsigned long),
1361 		.mode		= 0644,
1362 		.proc_handler	= hugetlb_sysctl_handler,
1363 	},
1364 #ifdef CONFIG_NUMA
1365 	{
1366 		.procname       = "nr_hugepages_mempolicy",
1367 		.data           = NULL,
1368 		.maxlen         = sizeof(unsigned long),
1369 		.mode           = 0644,
1370 		.proc_handler   = &hugetlb_mempolicy_sysctl_handler,
1371 	},
1372 #endif
1373 	 {
1374 		.procname	= "hugetlb_shm_group",
1375 		.data		= &sysctl_hugetlb_shm_group,
1376 		.maxlen		= sizeof(gid_t),
1377 		.mode		= 0644,
1378 		.proc_handler	= proc_dointvec,
1379 	 },
1380 	 {
1381 		.procname	= "hugepages_treat_as_movable",
1382 		.data		= &hugepages_treat_as_movable,
1383 		.maxlen		= sizeof(int),
1384 		.mode		= 0644,
1385 		.proc_handler	= proc_dointvec,
1386 	},
1387 	{
1388 		.procname	= "nr_overcommit_hugepages",
1389 		.data		= NULL,
1390 		.maxlen		= sizeof(unsigned long),
1391 		.mode		= 0644,
1392 		.proc_handler	= hugetlb_overcommit_handler,
1393 	},
1394 #endif
1395 	{
1396 		.procname	= "lowmem_reserve_ratio",
1397 		.data		= &sysctl_lowmem_reserve_ratio,
1398 		.maxlen		= sizeof(sysctl_lowmem_reserve_ratio),
1399 		.mode		= 0644,
1400 		.proc_handler	= lowmem_reserve_ratio_sysctl_handler,
1401 	},
1402 	{
1403 		.procname	= "drop_caches",
1404 		.data		= &sysctl_drop_caches,
1405 		.maxlen		= sizeof(int),
1406 		.mode		= 0644,
1407 		.proc_handler	= drop_caches_sysctl_handler,
1408 		.extra1		= &one,
1409 		.extra2		= &four,
1410 	},
1411 #ifdef CONFIG_COMPACTION
1412 	{
1413 		.procname	= "compact_memory",
1414 		.data		= &sysctl_compact_memory,
1415 		.maxlen		= sizeof(int),
1416 		.mode		= 0200,
1417 		.proc_handler	= sysctl_compaction_handler,
1418 	},
1419 	{
1420 		.procname	= "extfrag_threshold",
1421 		.data		= &sysctl_extfrag_threshold,
1422 		.maxlen		= sizeof(int),
1423 		.mode		= 0644,
1424 		.proc_handler	= sysctl_extfrag_handler,
1425 		.extra1		= &min_extfrag_threshold,
1426 		.extra2		= &max_extfrag_threshold,
1427 	},
1428 	{
1429 		.procname	= "compact_unevictable_allowed",
1430 		.data		= &sysctl_compact_unevictable_allowed,
1431 		.maxlen		= sizeof(int),
1432 		.mode		= 0644,
1433 		.proc_handler	= proc_dointvec,
1434 		.extra1		= &zero,
1435 		.extra2		= &one,
1436 	},
1437 
1438 #endif /* CONFIG_COMPACTION */
1439 	{
1440 		.procname	= "min_free_kbytes",
1441 		.data		= &min_free_kbytes,
1442 		.maxlen		= sizeof(min_free_kbytes),
1443 		.mode		= 0644,
1444 		.proc_handler	= min_free_kbytes_sysctl_handler,
1445 		.extra1		= &zero,
1446 	},
1447 	{
1448 		.procname	= "watermark_scale_factor",
1449 		.data		= &watermark_scale_factor,
1450 		.maxlen		= sizeof(watermark_scale_factor),
1451 		.mode		= 0644,
1452 		.proc_handler	= watermark_scale_factor_sysctl_handler,
1453 		.extra1		= &one,
1454 		.extra2		= &one_thousand,
1455 	},
1456 	{
1457 		.procname	= "percpu_pagelist_fraction",
1458 		.data		= &percpu_pagelist_fraction,
1459 		.maxlen		= sizeof(percpu_pagelist_fraction),
1460 		.mode		= 0644,
1461 		.proc_handler	= percpu_pagelist_fraction_sysctl_handler,
1462 		.extra1		= &zero,
1463 	},
1464 #ifdef CONFIG_MMU
1465 	{
1466 		.procname	= "max_map_count",
1467 		.data		= &sysctl_max_map_count,
1468 		.maxlen		= sizeof(sysctl_max_map_count),
1469 		.mode		= 0644,
1470 		.proc_handler	= proc_dointvec_minmax,
1471 		.extra1		= &zero,
1472 	},
1473 #else
1474 	{
1475 		.procname	= "nr_trim_pages",
1476 		.data		= &sysctl_nr_trim_pages,
1477 		.maxlen		= sizeof(sysctl_nr_trim_pages),
1478 		.mode		= 0644,
1479 		.proc_handler	= proc_dointvec_minmax,
1480 		.extra1		= &zero,
1481 	},
1482 #endif
1483 	{
1484 		.procname	= "laptop_mode",
1485 		.data		= &laptop_mode,
1486 		.maxlen		= sizeof(laptop_mode),
1487 		.mode		= 0644,
1488 		.proc_handler	= proc_dointvec_jiffies,
1489 	},
1490 	{
1491 		.procname	= "block_dump",
1492 		.data		= &block_dump,
1493 		.maxlen		= sizeof(block_dump),
1494 		.mode		= 0644,
1495 		.proc_handler	= proc_dointvec,
1496 		.extra1		= &zero,
1497 	},
1498 	{
1499 		.procname	= "vfs_cache_pressure",
1500 		.data		= &sysctl_vfs_cache_pressure,
1501 		.maxlen		= sizeof(sysctl_vfs_cache_pressure),
1502 		.mode		= 0644,
1503 		.proc_handler	= proc_dointvec,
1504 		.extra1		= &zero,
1505 	},
1506 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1507 	{
1508 		.procname	= "legacy_va_layout",
1509 		.data		= &sysctl_legacy_va_layout,
1510 		.maxlen		= sizeof(sysctl_legacy_va_layout),
1511 		.mode		= 0644,
1512 		.proc_handler	= proc_dointvec,
1513 		.extra1		= &zero,
1514 	},
1515 #endif
1516 #ifdef CONFIG_NUMA
1517 	{
1518 		.procname	= "zone_reclaim_mode",
1519 		.data		= &node_reclaim_mode,
1520 		.maxlen		= sizeof(node_reclaim_mode),
1521 		.mode		= 0644,
1522 		.proc_handler	= proc_dointvec,
1523 		.extra1		= &zero,
1524 	},
1525 	{
1526 		.procname	= "min_unmapped_ratio",
1527 		.data		= &sysctl_min_unmapped_ratio,
1528 		.maxlen		= sizeof(sysctl_min_unmapped_ratio),
1529 		.mode		= 0644,
1530 		.proc_handler	= sysctl_min_unmapped_ratio_sysctl_handler,
1531 		.extra1		= &zero,
1532 		.extra2		= &one_hundred,
1533 	},
1534 	{
1535 		.procname	= "min_slab_ratio",
1536 		.data		= &sysctl_min_slab_ratio,
1537 		.maxlen		= sizeof(sysctl_min_slab_ratio),
1538 		.mode		= 0644,
1539 		.proc_handler	= sysctl_min_slab_ratio_sysctl_handler,
1540 		.extra1		= &zero,
1541 		.extra2		= &one_hundred,
1542 	},
1543 #endif
1544 #ifdef CONFIG_SMP
1545 	{
1546 		.procname	= "stat_interval",
1547 		.data		= &sysctl_stat_interval,
1548 		.maxlen		= sizeof(sysctl_stat_interval),
1549 		.mode		= 0644,
1550 		.proc_handler	= proc_dointvec_jiffies,
1551 	},
1552 	{
1553 		.procname	= "stat_refresh",
1554 		.data		= NULL,
1555 		.maxlen		= 0,
1556 		.mode		= 0600,
1557 		.proc_handler	= vmstat_refresh,
1558 	},
1559 #endif
1560 #ifdef CONFIG_MMU
1561 	{
1562 		.procname	= "mmap_min_addr",
1563 		.data		= &dac_mmap_min_addr,
1564 		.maxlen		= sizeof(unsigned long),
1565 		.mode		= 0644,
1566 		.proc_handler	= mmap_min_addr_handler,
1567 	},
1568 #endif
1569 #ifdef CONFIG_NUMA
1570 	{
1571 		.procname	= "numa_zonelist_order",
1572 		.data		= &numa_zonelist_order,
1573 		.maxlen		= NUMA_ZONELIST_ORDER_LEN,
1574 		.mode		= 0644,
1575 		.proc_handler	= numa_zonelist_order_handler,
1576 	},
1577 #endif
1578 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1579    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1580 	{
1581 		.procname	= "vdso_enabled",
1582 #ifdef CONFIG_X86_32
1583 		.data		= &vdso32_enabled,
1584 		.maxlen		= sizeof(vdso32_enabled),
1585 #else
1586 		.data		= &vdso_enabled,
1587 		.maxlen		= sizeof(vdso_enabled),
1588 #endif
1589 		.mode		= 0644,
1590 		.proc_handler	= proc_dointvec,
1591 		.extra1		= &zero,
1592 	},
1593 #endif
1594 #ifdef CONFIG_HIGHMEM
1595 	{
1596 		.procname	= "highmem_is_dirtyable",
1597 		.data		= &vm_highmem_is_dirtyable,
1598 		.maxlen		= sizeof(vm_highmem_is_dirtyable),
1599 		.mode		= 0644,
1600 		.proc_handler	= proc_dointvec_minmax,
1601 		.extra1		= &zero,
1602 		.extra2		= &one,
1603 	},
1604 #endif
1605 #ifdef CONFIG_MEMORY_FAILURE
1606 	{
1607 		.procname	= "memory_failure_early_kill",
1608 		.data		= &sysctl_memory_failure_early_kill,
1609 		.maxlen		= sizeof(sysctl_memory_failure_early_kill),
1610 		.mode		= 0644,
1611 		.proc_handler	= proc_dointvec_minmax,
1612 		.extra1		= &zero,
1613 		.extra2		= &one,
1614 	},
1615 	{
1616 		.procname	= "memory_failure_recovery",
1617 		.data		= &sysctl_memory_failure_recovery,
1618 		.maxlen		= sizeof(sysctl_memory_failure_recovery),
1619 		.mode		= 0644,
1620 		.proc_handler	= proc_dointvec_minmax,
1621 		.extra1		= &zero,
1622 		.extra2		= &one,
1623 	},
1624 #endif
1625 	{
1626 		.procname	= "user_reserve_kbytes",
1627 		.data		= &sysctl_user_reserve_kbytes,
1628 		.maxlen		= sizeof(sysctl_user_reserve_kbytes),
1629 		.mode		= 0644,
1630 		.proc_handler	= proc_doulongvec_minmax,
1631 	},
1632 	{
1633 		.procname	= "admin_reserve_kbytes",
1634 		.data		= &sysctl_admin_reserve_kbytes,
1635 		.maxlen		= sizeof(sysctl_admin_reserve_kbytes),
1636 		.mode		= 0644,
1637 		.proc_handler	= proc_doulongvec_minmax,
1638 	},
1639 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
1640 	{
1641 		.procname	= "mmap_rnd_bits",
1642 		.data		= &mmap_rnd_bits,
1643 		.maxlen		= sizeof(mmap_rnd_bits),
1644 		.mode		= 0600,
1645 		.proc_handler	= proc_dointvec_minmax,
1646 		.extra1		= (void *)&mmap_rnd_bits_min,
1647 		.extra2		= (void *)&mmap_rnd_bits_max,
1648 	},
1649 #endif
1650 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
1651 	{
1652 		.procname	= "mmap_rnd_compat_bits",
1653 		.data		= &mmap_rnd_compat_bits,
1654 		.maxlen		= sizeof(mmap_rnd_compat_bits),
1655 		.mode		= 0600,
1656 		.proc_handler	= proc_dointvec_minmax,
1657 		.extra1		= (void *)&mmap_rnd_compat_bits_min,
1658 		.extra2		= (void *)&mmap_rnd_compat_bits_max,
1659 	},
1660 #endif
1661 	{ }
1662 };
1663 
1664 static struct ctl_table fs_table[] = {
1665 	{
1666 		.procname	= "inode-nr",
1667 		.data		= &inodes_stat,
1668 		.maxlen		= 2*sizeof(long),
1669 		.mode		= 0444,
1670 		.proc_handler	= proc_nr_inodes,
1671 	},
1672 	{
1673 		.procname	= "inode-state",
1674 		.data		= &inodes_stat,
1675 		.maxlen		= 7*sizeof(long),
1676 		.mode		= 0444,
1677 		.proc_handler	= proc_nr_inodes,
1678 	},
1679 	{
1680 		.procname	= "file-nr",
1681 		.data		= &files_stat,
1682 		.maxlen		= sizeof(files_stat),
1683 		.mode		= 0444,
1684 		.proc_handler	= proc_nr_files,
1685 	},
1686 	{
1687 		.procname	= "file-max",
1688 		.data		= &files_stat.max_files,
1689 		.maxlen		= sizeof(files_stat.max_files),
1690 		.mode		= 0644,
1691 		.proc_handler	= proc_doulongvec_minmax,
1692 	},
1693 	{
1694 		.procname	= "nr_open",
1695 		.data		= &sysctl_nr_open,
1696 		.maxlen		= sizeof(unsigned int),
1697 		.mode		= 0644,
1698 		.proc_handler	= proc_dointvec_minmax,
1699 		.extra1		= &sysctl_nr_open_min,
1700 		.extra2		= &sysctl_nr_open_max,
1701 	},
1702 	{
1703 		.procname	= "dentry-state",
1704 		.data		= &dentry_stat,
1705 		.maxlen		= 6*sizeof(long),
1706 		.mode		= 0444,
1707 		.proc_handler	= proc_nr_dentry,
1708 	},
1709 	{
1710 		.procname	= "overflowuid",
1711 		.data		= &fs_overflowuid,
1712 		.maxlen		= sizeof(int),
1713 		.mode		= 0644,
1714 		.proc_handler	= proc_dointvec_minmax,
1715 		.extra1		= &minolduid,
1716 		.extra2		= &maxolduid,
1717 	},
1718 	{
1719 		.procname	= "overflowgid",
1720 		.data		= &fs_overflowgid,
1721 		.maxlen		= sizeof(int),
1722 		.mode		= 0644,
1723 		.proc_handler	= proc_dointvec_minmax,
1724 		.extra1		= &minolduid,
1725 		.extra2		= &maxolduid,
1726 	},
1727 #ifdef CONFIG_FILE_LOCKING
1728 	{
1729 		.procname	= "leases-enable",
1730 		.data		= &leases_enable,
1731 		.maxlen		= sizeof(int),
1732 		.mode		= 0644,
1733 		.proc_handler	= proc_dointvec,
1734 	},
1735 #endif
1736 #ifdef CONFIG_DNOTIFY
1737 	{
1738 		.procname	= "dir-notify-enable",
1739 		.data		= &dir_notify_enable,
1740 		.maxlen		= sizeof(int),
1741 		.mode		= 0644,
1742 		.proc_handler	= proc_dointvec,
1743 	},
1744 #endif
1745 #ifdef CONFIG_MMU
1746 #ifdef CONFIG_FILE_LOCKING
1747 	{
1748 		.procname	= "lease-break-time",
1749 		.data		= &lease_break_time,
1750 		.maxlen		= sizeof(int),
1751 		.mode		= 0644,
1752 		.proc_handler	= proc_dointvec,
1753 	},
1754 #endif
1755 #ifdef CONFIG_AIO
1756 	{
1757 		.procname	= "aio-nr",
1758 		.data		= &aio_nr,
1759 		.maxlen		= sizeof(aio_nr),
1760 		.mode		= 0444,
1761 		.proc_handler	= proc_doulongvec_minmax,
1762 	},
1763 	{
1764 		.procname	= "aio-max-nr",
1765 		.data		= &aio_max_nr,
1766 		.maxlen		= sizeof(aio_max_nr),
1767 		.mode		= 0644,
1768 		.proc_handler	= proc_doulongvec_minmax,
1769 	},
1770 #endif /* CONFIG_AIO */
1771 #ifdef CONFIG_INOTIFY_USER
1772 	{
1773 		.procname	= "inotify",
1774 		.mode		= 0555,
1775 		.child		= inotify_table,
1776 	},
1777 #endif
1778 #ifdef CONFIG_EPOLL
1779 	{
1780 		.procname	= "epoll",
1781 		.mode		= 0555,
1782 		.child		= epoll_table,
1783 	},
1784 #endif
1785 #endif
1786 	{
1787 		.procname	= "protected_symlinks",
1788 		.data		= &sysctl_protected_symlinks,
1789 		.maxlen		= sizeof(int),
1790 		.mode		= 0600,
1791 		.proc_handler	= proc_dointvec_minmax,
1792 		.extra1		= &zero,
1793 		.extra2		= &one,
1794 	},
1795 	{
1796 		.procname	= "protected_hardlinks",
1797 		.data		= &sysctl_protected_hardlinks,
1798 		.maxlen		= sizeof(int),
1799 		.mode		= 0600,
1800 		.proc_handler	= proc_dointvec_minmax,
1801 		.extra1		= &zero,
1802 		.extra2		= &one,
1803 	},
1804 	{
1805 		.procname	= "suid_dumpable",
1806 		.data		= &suid_dumpable,
1807 		.maxlen		= sizeof(int),
1808 		.mode		= 0644,
1809 		.proc_handler	= proc_dointvec_minmax_coredump,
1810 		.extra1		= &zero,
1811 		.extra2		= &two,
1812 	},
1813 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1814 	{
1815 		.procname	= "binfmt_misc",
1816 		.mode		= 0555,
1817 		.child		= sysctl_mount_point,
1818 	},
1819 #endif
1820 	{
1821 		.procname	= "pipe-max-size",
1822 		.data		= &pipe_max_size,
1823 		.maxlen		= sizeof(int),
1824 		.mode		= 0644,
1825 		.proc_handler	= &pipe_proc_fn,
1826 		.extra1		= &pipe_min_size,
1827 	},
1828 	{
1829 		.procname	= "pipe-user-pages-hard",
1830 		.data		= &pipe_user_pages_hard,
1831 		.maxlen		= sizeof(pipe_user_pages_hard),
1832 		.mode		= 0644,
1833 		.proc_handler	= proc_doulongvec_minmax,
1834 	},
1835 	{
1836 		.procname	= "pipe-user-pages-soft",
1837 		.data		= &pipe_user_pages_soft,
1838 		.maxlen		= sizeof(pipe_user_pages_soft),
1839 		.mode		= 0644,
1840 		.proc_handler	= proc_doulongvec_minmax,
1841 	},
1842 	{
1843 		.procname	= "mount-max",
1844 		.data		= &sysctl_mount_max,
1845 		.maxlen		= sizeof(unsigned int),
1846 		.mode		= 0644,
1847 		.proc_handler	= proc_dointvec_minmax,
1848 		.extra1		= &one,
1849 	},
1850 	{ }
1851 };
1852 
1853 static struct ctl_table debug_table[] = {
1854 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1855 	{
1856 		.procname	= "exception-trace",
1857 		.data		= &show_unhandled_signals,
1858 		.maxlen		= sizeof(int),
1859 		.mode		= 0644,
1860 		.proc_handler	= proc_dointvec
1861 	},
1862 #endif
1863 #if defined(CONFIG_OPTPROBES)
1864 	{
1865 		.procname	= "kprobes-optimization",
1866 		.data		= &sysctl_kprobes_optimization,
1867 		.maxlen		= sizeof(int),
1868 		.mode		= 0644,
1869 		.proc_handler	= proc_kprobes_optimization_handler,
1870 		.extra1		= &zero,
1871 		.extra2		= &one,
1872 	},
1873 #endif
1874 	{ }
1875 };
1876 
1877 static struct ctl_table dev_table[] = {
1878 	{ }
1879 };
1880 
1881 int __init sysctl_init(void)
1882 {
1883 	struct ctl_table_header *hdr;
1884 
1885 	hdr = register_sysctl_table(sysctl_base_table);
1886 	kmemleak_not_leak(hdr);
1887 	return 0;
1888 }
1889 
1890 #endif /* CONFIG_SYSCTL */
1891 
1892 /*
1893  * /proc/sys support
1894  */
1895 
1896 #ifdef CONFIG_PROC_SYSCTL
1897 
1898 static int _proc_do_string(char *data, int maxlen, int write,
1899 			   char __user *buffer,
1900 			   size_t *lenp, loff_t *ppos)
1901 {
1902 	size_t len;
1903 	char __user *p;
1904 	char c;
1905 
1906 	if (!data || !maxlen || !*lenp) {
1907 		*lenp = 0;
1908 		return 0;
1909 	}
1910 
1911 	if (write) {
1912 		if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
1913 			/* Only continue writes not past the end of buffer. */
1914 			len = strlen(data);
1915 			if (len > maxlen - 1)
1916 				len = maxlen - 1;
1917 
1918 			if (*ppos > len)
1919 				return 0;
1920 			len = *ppos;
1921 		} else {
1922 			/* Start writing from beginning of buffer. */
1923 			len = 0;
1924 		}
1925 
1926 		*ppos += *lenp;
1927 		p = buffer;
1928 		while ((p - buffer) < *lenp && len < maxlen - 1) {
1929 			if (get_user(c, p++))
1930 				return -EFAULT;
1931 			if (c == 0 || c == '\n')
1932 				break;
1933 			data[len++] = c;
1934 		}
1935 		data[len] = 0;
1936 	} else {
1937 		len = strlen(data);
1938 		if (len > maxlen)
1939 			len = maxlen;
1940 
1941 		if (*ppos > len) {
1942 			*lenp = 0;
1943 			return 0;
1944 		}
1945 
1946 		data += *ppos;
1947 		len  -= *ppos;
1948 
1949 		if (len > *lenp)
1950 			len = *lenp;
1951 		if (len)
1952 			if (copy_to_user(buffer, data, len))
1953 				return -EFAULT;
1954 		if (len < *lenp) {
1955 			if (put_user('\n', buffer + len))
1956 				return -EFAULT;
1957 			len++;
1958 		}
1959 		*lenp = len;
1960 		*ppos += len;
1961 	}
1962 	return 0;
1963 }
1964 
1965 static void warn_sysctl_write(struct ctl_table *table)
1966 {
1967 	pr_warn_once("%s wrote to %s when file position was not 0!\n"
1968 		"This will not be supported in the future. To silence this\n"
1969 		"warning, set kernel.sysctl_writes_strict = -1\n",
1970 		current->comm, table->procname);
1971 }
1972 
1973 /**
1974  * proc_first_pos_non_zero_ignore - check if firs position is allowed
1975  * @ppos: file position
1976  * @table: the sysctl table
1977  *
1978  * Returns true if the first position is non-zero and the sysctl_writes_strict
1979  * mode indicates this is not allowed for numeric input types. String proc
1980  * hadlers can ignore the return value.
1981  */
1982 static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
1983 					   struct ctl_table *table)
1984 {
1985 	if (!*ppos)
1986 		return false;
1987 
1988 	switch (sysctl_writes_strict) {
1989 	case SYSCTL_WRITES_STRICT:
1990 		return true;
1991 	case SYSCTL_WRITES_WARN:
1992 		warn_sysctl_write(table);
1993 		return false;
1994 	default:
1995 		return false;
1996 	}
1997 }
1998 
1999 /**
2000  * proc_dostring - read a string sysctl
2001  * @table: the sysctl table
2002  * @write: %TRUE if this is a write to the sysctl file
2003  * @buffer: the user buffer
2004  * @lenp: the size of the user buffer
2005  * @ppos: file position
2006  *
2007  * Reads/writes a string from/to the user buffer. If the kernel
2008  * buffer provided is not large enough to hold the string, the
2009  * string is truncated. The copied string is %NULL-terminated.
2010  * If the string is being read by the user process, it is copied
2011  * and a newline '\n' is added. It is truncated if the buffer is
2012  * not large enough.
2013  *
2014  * Returns 0 on success.
2015  */
2016 int proc_dostring(struct ctl_table *table, int write,
2017 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2018 {
2019 	if (write)
2020 		proc_first_pos_non_zero_ignore(ppos, table);
2021 
2022 	return _proc_do_string((char *)(table->data), table->maxlen, write,
2023 			       (char __user *)buffer, lenp, ppos);
2024 }
2025 
2026 static size_t proc_skip_spaces(char **buf)
2027 {
2028 	size_t ret;
2029 	char *tmp = skip_spaces(*buf);
2030 	ret = tmp - *buf;
2031 	*buf = tmp;
2032 	return ret;
2033 }
2034 
2035 static void proc_skip_char(char **buf, size_t *size, const char v)
2036 {
2037 	while (*size) {
2038 		if (**buf != v)
2039 			break;
2040 		(*size)--;
2041 		(*buf)++;
2042 	}
2043 }
2044 
2045 #define TMPBUFLEN 22
2046 /**
2047  * proc_get_long - reads an ASCII formatted integer from a user buffer
2048  *
2049  * @buf: a kernel buffer
2050  * @size: size of the kernel buffer
2051  * @val: this is where the number will be stored
2052  * @neg: set to %TRUE if number is negative
2053  * @perm_tr: a vector which contains the allowed trailers
2054  * @perm_tr_len: size of the perm_tr vector
2055  * @tr: pointer to store the trailer character
2056  *
2057  * In case of success %0 is returned and @buf and @size are updated with
2058  * the amount of bytes read. If @tr is non-NULL and a trailing
2059  * character exists (size is non-zero after returning from this
2060  * function), @tr is updated with the trailing character.
2061  */
2062 static int proc_get_long(char **buf, size_t *size,
2063 			  unsigned long *val, bool *neg,
2064 			  const char *perm_tr, unsigned perm_tr_len, char *tr)
2065 {
2066 	int len;
2067 	char *p, tmp[TMPBUFLEN];
2068 
2069 	if (!*size)
2070 		return -EINVAL;
2071 
2072 	len = *size;
2073 	if (len > TMPBUFLEN - 1)
2074 		len = TMPBUFLEN - 1;
2075 
2076 	memcpy(tmp, *buf, len);
2077 
2078 	tmp[len] = 0;
2079 	p = tmp;
2080 	if (*p == '-' && *size > 1) {
2081 		*neg = true;
2082 		p++;
2083 	} else
2084 		*neg = false;
2085 	if (!isdigit(*p))
2086 		return -EINVAL;
2087 
2088 	*val = simple_strtoul(p, &p, 0);
2089 
2090 	len = p - tmp;
2091 
2092 	/* We don't know if the next char is whitespace thus we may accept
2093 	 * invalid integers (e.g. 1234...a) or two integers instead of one
2094 	 * (e.g. 123...1). So lets not allow such large numbers. */
2095 	if (len == TMPBUFLEN - 1)
2096 		return -EINVAL;
2097 
2098 	if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2099 		return -EINVAL;
2100 
2101 	if (tr && (len < *size))
2102 		*tr = *p;
2103 
2104 	*buf += len;
2105 	*size -= len;
2106 
2107 	return 0;
2108 }
2109 
2110 /**
2111  * proc_put_long - converts an integer to a decimal ASCII formatted string
2112  *
2113  * @buf: the user buffer
2114  * @size: the size of the user buffer
2115  * @val: the integer to be converted
2116  * @neg: sign of the number, %TRUE for negative
2117  *
2118  * In case of success %0 is returned and @buf and @size are updated with
2119  * the amount of bytes written.
2120  */
2121 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2122 			  bool neg)
2123 {
2124 	int len;
2125 	char tmp[TMPBUFLEN], *p = tmp;
2126 
2127 	sprintf(p, "%s%lu", neg ? "-" : "", val);
2128 	len = strlen(tmp);
2129 	if (len > *size)
2130 		len = *size;
2131 	if (copy_to_user(*buf, tmp, len))
2132 		return -EFAULT;
2133 	*size -= len;
2134 	*buf += len;
2135 	return 0;
2136 }
2137 #undef TMPBUFLEN
2138 
2139 static int proc_put_char(void __user **buf, size_t *size, char c)
2140 {
2141 	if (*size) {
2142 		char __user **buffer = (char __user **)buf;
2143 		if (put_user(c, *buffer))
2144 			return -EFAULT;
2145 		(*size)--, (*buffer)++;
2146 		*buf = *buffer;
2147 	}
2148 	return 0;
2149 }
2150 
2151 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2152 				 int *valp,
2153 				 int write, void *data)
2154 {
2155 	if (write) {
2156 		if (*negp) {
2157 			if (*lvalp > (unsigned long) INT_MAX + 1)
2158 				return -EINVAL;
2159 			*valp = -*lvalp;
2160 		} else {
2161 			if (*lvalp > (unsigned long) INT_MAX)
2162 				return -EINVAL;
2163 			*valp = *lvalp;
2164 		}
2165 	} else {
2166 		int val = *valp;
2167 		if (val < 0) {
2168 			*negp = true;
2169 			*lvalp = -(unsigned long)val;
2170 		} else {
2171 			*negp = false;
2172 			*lvalp = (unsigned long)val;
2173 		}
2174 	}
2175 	return 0;
2176 }
2177 
2178 static int do_proc_douintvec_conv(unsigned long *lvalp,
2179 				  unsigned int *valp,
2180 				  int write, void *data)
2181 {
2182 	if (write) {
2183 		if (*lvalp > UINT_MAX)
2184 			return -EINVAL;
2185 		if (*lvalp > UINT_MAX)
2186 			return -EINVAL;
2187 		*valp = *lvalp;
2188 	} else {
2189 		unsigned int val = *valp;
2190 		*lvalp = (unsigned long)val;
2191 	}
2192 	return 0;
2193 }
2194 
2195 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2196 
2197 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2198 		  int write, void __user *buffer,
2199 		  size_t *lenp, loff_t *ppos,
2200 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2201 			      int write, void *data),
2202 		  void *data)
2203 {
2204 	int *i, vleft, first = 1, err = 0;
2205 	size_t left;
2206 	char *kbuf = NULL, *p;
2207 
2208 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2209 		*lenp = 0;
2210 		return 0;
2211 	}
2212 
2213 	i = (int *) tbl_data;
2214 	vleft = table->maxlen / sizeof(*i);
2215 	left = *lenp;
2216 
2217 	if (!conv)
2218 		conv = do_proc_dointvec_conv;
2219 
2220 	if (write) {
2221 		if (proc_first_pos_non_zero_ignore(ppos, table))
2222 			goto out;
2223 
2224 		if (left > PAGE_SIZE - 1)
2225 			left = PAGE_SIZE - 1;
2226 		p = kbuf = memdup_user_nul(buffer, left);
2227 		if (IS_ERR(kbuf))
2228 			return PTR_ERR(kbuf);
2229 	}
2230 
2231 	for (; left && vleft--; i++, first=0) {
2232 		unsigned long lval;
2233 		bool neg;
2234 
2235 		if (write) {
2236 			left -= proc_skip_spaces(&p);
2237 
2238 			if (!left)
2239 				break;
2240 			err = proc_get_long(&p, &left, &lval, &neg,
2241 					     proc_wspace_sep,
2242 					     sizeof(proc_wspace_sep), NULL);
2243 			if (err)
2244 				break;
2245 			if (conv(&neg, &lval, i, 1, data)) {
2246 				err = -EINVAL;
2247 				break;
2248 			}
2249 		} else {
2250 			if (conv(&neg, &lval, i, 0, data)) {
2251 				err = -EINVAL;
2252 				break;
2253 			}
2254 			if (!first)
2255 				err = proc_put_char(&buffer, &left, '\t');
2256 			if (err)
2257 				break;
2258 			err = proc_put_long(&buffer, &left, lval, neg);
2259 			if (err)
2260 				break;
2261 		}
2262 	}
2263 
2264 	if (!write && !first && left && !err)
2265 		err = proc_put_char(&buffer, &left, '\n');
2266 	if (write && !err && left)
2267 		left -= proc_skip_spaces(&p);
2268 	if (write) {
2269 		kfree(kbuf);
2270 		if (first)
2271 			return err ? : -EINVAL;
2272 	}
2273 	*lenp -= left;
2274 out:
2275 	*ppos += *lenp;
2276 	return err;
2277 }
2278 
2279 static int do_proc_dointvec(struct ctl_table *table, int write,
2280 		  void __user *buffer, size_t *lenp, loff_t *ppos,
2281 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2282 			      int write, void *data),
2283 		  void *data)
2284 {
2285 	return __do_proc_dointvec(table->data, table, write,
2286 			buffer, lenp, ppos, conv, data);
2287 }
2288 
2289 static int do_proc_douintvec_w(unsigned int *tbl_data,
2290 			       struct ctl_table *table,
2291 			       void __user *buffer,
2292 			       size_t *lenp, loff_t *ppos,
2293 			       int (*conv)(unsigned long *lvalp,
2294 					   unsigned int *valp,
2295 					   int write, void *data),
2296 			       void *data)
2297 {
2298 	unsigned long lval;
2299 	int err = 0;
2300 	size_t left;
2301 	bool neg;
2302 	char *kbuf = NULL, *p;
2303 
2304 	left = *lenp;
2305 
2306 	if (proc_first_pos_non_zero_ignore(ppos, table))
2307 		goto bail_early;
2308 
2309 	if (left > PAGE_SIZE - 1)
2310 		left = PAGE_SIZE - 1;
2311 
2312 	p = kbuf = memdup_user_nul(buffer, left);
2313 	if (IS_ERR(kbuf))
2314 		return -EINVAL;
2315 
2316 	left -= proc_skip_spaces(&p);
2317 	if (!left) {
2318 		err = -EINVAL;
2319 		goto out_free;
2320 	}
2321 
2322 	err = proc_get_long(&p, &left, &lval, &neg,
2323 			     proc_wspace_sep,
2324 			     sizeof(proc_wspace_sep), NULL);
2325 	if (err || neg) {
2326 		err = -EINVAL;
2327 		goto out_free;
2328 	}
2329 
2330 	if (conv(&lval, tbl_data, 1, data)) {
2331 		err = -EINVAL;
2332 		goto out_free;
2333 	}
2334 
2335 	if (!err && left)
2336 		left -= proc_skip_spaces(&p);
2337 
2338 out_free:
2339 	kfree(kbuf);
2340 	if (err)
2341 		return -EINVAL;
2342 
2343 	return 0;
2344 
2345 	/* This is in keeping with old __do_proc_dointvec() */
2346 bail_early:
2347 	*ppos += *lenp;
2348 	return err;
2349 }
2350 
2351 static int do_proc_douintvec_r(unsigned int *tbl_data, void __user *buffer,
2352 			       size_t *lenp, loff_t *ppos,
2353 			       int (*conv)(unsigned long *lvalp,
2354 					   unsigned int *valp,
2355 					   int write, void *data),
2356 			       void *data)
2357 {
2358 	unsigned long lval;
2359 	int err = 0;
2360 	size_t left;
2361 
2362 	left = *lenp;
2363 
2364 	if (conv(&lval, tbl_data, 0, data)) {
2365 		err = -EINVAL;
2366 		goto out;
2367 	}
2368 
2369 	err = proc_put_long(&buffer, &left, lval, false);
2370 	if (err || !left)
2371 		goto out;
2372 
2373 	err = proc_put_char(&buffer, &left, '\n');
2374 
2375 out:
2376 	*lenp -= left;
2377 	*ppos += *lenp;
2378 
2379 	return err;
2380 }
2381 
2382 static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
2383 			       int write, void __user *buffer,
2384 			       size_t *lenp, loff_t *ppos,
2385 			       int (*conv)(unsigned long *lvalp,
2386 					   unsigned int *valp,
2387 					   int write, void *data),
2388 			       void *data)
2389 {
2390 	unsigned int *i, vleft;
2391 
2392 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2393 		*lenp = 0;
2394 		return 0;
2395 	}
2396 
2397 	i = (unsigned int *) tbl_data;
2398 	vleft = table->maxlen / sizeof(*i);
2399 
2400 	/*
2401 	 * Arrays are not supported, keep this simple. *Do not* add
2402 	 * support for them.
2403 	 */
2404 	if (vleft != 1) {
2405 		*lenp = 0;
2406 		return -EINVAL;
2407 	}
2408 
2409 	if (!conv)
2410 		conv = do_proc_douintvec_conv;
2411 
2412 	if (write)
2413 		return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
2414 					   conv, data);
2415 	return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
2416 }
2417 
2418 static int do_proc_douintvec(struct ctl_table *table, int write,
2419 			     void __user *buffer, size_t *lenp, loff_t *ppos,
2420 			     int (*conv)(unsigned long *lvalp,
2421 					 unsigned int *valp,
2422 					 int write, void *data),
2423 			     void *data)
2424 {
2425 	return __do_proc_douintvec(table->data, table, write,
2426 				   buffer, lenp, ppos, conv, data);
2427 }
2428 
2429 /**
2430  * proc_dointvec - read a vector of integers
2431  * @table: the sysctl table
2432  * @write: %TRUE if this is a write to the sysctl file
2433  * @buffer: the user buffer
2434  * @lenp: the size of the user buffer
2435  * @ppos: file position
2436  *
2437  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2438  * values from/to the user buffer, treated as an ASCII string.
2439  *
2440  * Returns 0 on success.
2441  */
2442 int proc_dointvec(struct ctl_table *table, int write,
2443 		     void __user *buffer, size_t *lenp, loff_t *ppos)
2444 {
2445 	return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
2446 }
2447 
2448 /**
2449  * proc_douintvec - read a vector of unsigned integers
2450  * @table: the sysctl table
2451  * @write: %TRUE if this is a write to the sysctl file
2452  * @buffer: the user buffer
2453  * @lenp: the size of the user buffer
2454  * @ppos: file position
2455  *
2456  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2457  * values from/to the user buffer, treated as an ASCII string.
2458  *
2459  * Returns 0 on success.
2460  */
2461 int proc_douintvec(struct ctl_table *table, int write,
2462 		     void __user *buffer, size_t *lenp, loff_t *ppos)
2463 {
2464 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
2465 				 do_proc_douintvec_conv, NULL);
2466 }
2467 
2468 /*
2469  * Taint values can only be increased
2470  * This means we can safely use a temporary.
2471  */
2472 static int proc_taint(struct ctl_table *table, int write,
2473 			       void __user *buffer, size_t *lenp, loff_t *ppos)
2474 {
2475 	struct ctl_table t;
2476 	unsigned long tmptaint = get_taint();
2477 	int err;
2478 
2479 	if (write && !capable(CAP_SYS_ADMIN))
2480 		return -EPERM;
2481 
2482 	t = *table;
2483 	t.data = &tmptaint;
2484 	err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2485 	if (err < 0)
2486 		return err;
2487 
2488 	if (write) {
2489 		/*
2490 		 * Poor man's atomic or. Not worth adding a primitive
2491 		 * to everyone's atomic.h for this
2492 		 */
2493 		int i;
2494 		for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2495 			if ((tmptaint >> i) & 1)
2496 				add_taint(i, LOCKDEP_STILL_OK);
2497 		}
2498 	}
2499 
2500 	return err;
2501 }
2502 
2503 #ifdef CONFIG_PRINTK
2504 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2505 				void __user *buffer, size_t *lenp, loff_t *ppos)
2506 {
2507 	if (write && !capable(CAP_SYS_ADMIN))
2508 		return -EPERM;
2509 
2510 	return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2511 }
2512 #endif
2513 
2514 struct do_proc_dointvec_minmax_conv_param {
2515 	int *min;
2516 	int *max;
2517 };
2518 
2519 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2520 					int *valp,
2521 					int write, void *data)
2522 {
2523 	struct do_proc_dointvec_minmax_conv_param *param = data;
2524 	if (write) {
2525 		int val = *negp ? -*lvalp : *lvalp;
2526 		if ((param->min && *param->min > val) ||
2527 		    (param->max && *param->max < val))
2528 			return -EINVAL;
2529 		*valp = val;
2530 	} else {
2531 		int val = *valp;
2532 		if (val < 0) {
2533 			*negp = true;
2534 			*lvalp = -(unsigned long)val;
2535 		} else {
2536 			*negp = false;
2537 			*lvalp = (unsigned long)val;
2538 		}
2539 	}
2540 	return 0;
2541 }
2542 
2543 /**
2544  * proc_dointvec_minmax - read a vector of integers with min/max values
2545  * @table: the sysctl table
2546  * @write: %TRUE if this is a write to the sysctl file
2547  * @buffer: the user buffer
2548  * @lenp: the size of the user buffer
2549  * @ppos: file position
2550  *
2551  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2552  * values from/to the user buffer, treated as an ASCII string.
2553  *
2554  * This routine will ensure the values are within the range specified by
2555  * table->extra1 (min) and table->extra2 (max).
2556  *
2557  * Returns 0 on success.
2558  */
2559 int proc_dointvec_minmax(struct ctl_table *table, int write,
2560 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2561 {
2562 	struct do_proc_dointvec_minmax_conv_param param = {
2563 		.min = (int *) table->extra1,
2564 		.max = (int *) table->extra2,
2565 	};
2566 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
2567 				do_proc_dointvec_minmax_conv, &param);
2568 }
2569 
2570 struct do_proc_douintvec_minmax_conv_param {
2571 	unsigned int *min;
2572 	unsigned int *max;
2573 };
2574 
2575 static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
2576 					 unsigned int *valp,
2577 					 int write, void *data)
2578 {
2579 	struct do_proc_douintvec_minmax_conv_param *param = data;
2580 
2581 	if (write) {
2582 		unsigned int val = *lvalp;
2583 
2584 		if ((param->min && *param->min > val) ||
2585 		    (param->max && *param->max < val))
2586 			return -ERANGE;
2587 
2588 		if (*lvalp > UINT_MAX)
2589 			return -EINVAL;
2590 		*valp = val;
2591 	} else {
2592 		unsigned int val = *valp;
2593 		*lvalp = (unsigned long) val;
2594 	}
2595 
2596 	return 0;
2597 }
2598 
2599 /**
2600  * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
2601  * @table: the sysctl table
2602  * @write: %TRUE if this is a write to the sysctl file
2603  * @buffer: the user buffer
2604  * @lenp: the size of the user buffer
2605  * @ppos: file position
2606  *
2607  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2608  * values from/to the user buffer, treated as an ASCII string. Negative
2609  * strings are not allowed.
2610  *
2611  * This routine will ensure the values are within the range specified by
2612  * table->extra1 (min) and table->extra2 (max). There is a final sanity
2613  * check for UINT_MAX to avoid having to support wrap around uses from
2614  * userspace.
2615  *
2616  * Returns 0 on success.
2617  */
2618 int proc_douintvec_minmax(struct ctl_table *table, int write,
2619 			  void __user *buffer, size_t *lenp, loff_t *ppos)
2620 {
2621 	struct do_proc_douintvec_minmax_conv_param param = {
2622 		.min = (unsigned int *) table->extra1,
2623 		.max = (unsigned int *) table->extra2,
2624 	};
2625 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
2626 				 do_proc_douintvec_minmax_conv, &param);
2627 }
2628 
2629 static void validate_coredump_safety(void)
2630 {
2631 #ifdef CONFIG_COREDUMP
2632 	if (suid_dumpable == SUID_DUMP_ROOT &&
2633 	    core_pattern[0] != '/' && core_pattern[0] != '|') {
2634 		printk(KERN_WARNING
2635 "Unsafe core_pattern used with fs.suid_dumpable=2.\n"
2636 "Pipe handler or fully qualified core dump path required.\n"
2637 "Set kernel.core_pattern before fs.suid_dumpable.\n"
2638 		);
2639 	}
2640 #endif
2641 }
2642 
2643 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2644 		void __user *buffer, size_t *lenp, loff_t *ppos)
2645 {
2646 	int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2647 	if (!error)
2648 		validate_coredump_safety();
2649 	return error;
2650 }
2651 
2652 #ifdef CONFIG_COREDUMP
2653 static int proc_dostring_coredump(struct ctl_table *table, int write,
2654 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2655 {
2656 	int error = proc_dostring(table, write, buffer, lenp, ppos);
2657 	if (!error)
2658 		validate_coredump_safety();
2659 	return error;
2660 }
2661 #endif
2662 
2663 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2664 				     void __user *buffer,
2665 				     size_t *lenp, loff_t *ppos,
2666 				     unsigned long convmul,
2667 				     unsigned long convdiv)
2668 {
2669 	unsigned long *i, *min, *max;
2670 	int vleft, first = 1, err = 0;
2671 	size_t left;
2672 	char *kbuf = NULL, *p;
2673 
2674 	if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2675 		*lenp = 0;
2676 		return 0;
2677 	}
2678 
2679 	i = (unsigned long *) data;
2680 	min = (unsigned long *) table->extra1;
2681 	max = (unsigned long *) table->extra2;
2682 	vleft = table->maxlen / sizeof(unsigned long);
2683 	left = *lenp;
2684 
2685 	if (write) {
2686 		if (proc_first_pos_non_zero_ignore(ppos, table))
2687 			goto out;
2688 
2689 		if (left > PAGE_SIZE - 1)
2690 			left = PAGE_SIZE - 1;
2691 		p = kbuf = memdup_user_nul(buffer, left);
2692 		if (IS_ERR(kbuf))
2693 			return PTR_ERR(kbuf);
2694 	}
2695 
2696 	for (; left && vleft--; i++, first = 0) {
2697 		unsigned long val;
2698 
2699 		if (write) {
2700 			bool neg;
2701 
2702 			left -= proc_skip_spaces(&p);
2703 
2704 			err = proc_get_long(&p, &left, &val, &neg,
2705 					     proc_wspace_sep,
2706 					     sizeof(proc_wspace_sep), NULL);
2707 			if (err)
2708 				break;
2709 			if (neg)
2710 				continue;
2711 			val = convmul * val / convdiv;
2712 			if ((min && val < *min) || (max && val > *max))
2713 				continue;
2714 			*i = val;
2715 		} else {
2716 			val = convdiv * (*i) / convmul;
2717 			if (!first) {
2718 				err = proc_put_char(&buffer, &left, '\t');
2719 				if (err)
2720 					break;
2721 			}
2722 			err = proc_put_long(&buffer, &left, val, false);
2723 			if (err)
2724 				break;
2725 		}
2726 	}
2727 
2728 	if (!write && !first && left && !err)
2729 		err = proc_put_char(&buffer, &left, '\n');
2730 	if (write && !err)
2731 		left -= proc_skip_spaces(&p);
2732 	if (write) {
2733 		kfree(kbuf);
2734 		if (first)
2735 			return err ? : -EINVAL;
2736 	}
2737 	*lenp -= left;
2738 out:
2739 	*ppos += *lenp;
2740 	return err;
2741 }
2742 
2743 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2744 				     void __user *buffer,
2745 				     size_t *lenp, loff_t *ppos,
2746 				     unsigned long convmul,
2747 				     unsigned long convdiv)
2748 {
2749 	return __do_proc_doulongvec_minmax(table->data, table, write,
2750 			buffer, lenp, ppos, convmul, convdiv);
2751 }
2752 
2753 /**
2754  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2755  * @table: the sysctl table
2756  * @write: %TRUE if this is a write to the sysctl file
2757  * @buffer: the user buffer
2758  * @lenp: the size of the user buffer
2759  * @ppos: file position
2760  *
2761  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2762  * values from/to the user buffer, treated as an ASCII string.
2763  *
2764  * This routine will ensure the values are within the range specified by
2765  * table->extra1 (min) and table->extra2 (max).
2766  *
2767  * Returns 0 on success.
2768  */
2769 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2770 			   void __user *buffer, size_t *lenp, loff_t *ppos)
2771 {
2772     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2773 }
2774 
2775 /**
2776  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2777  * @table: the sysctl table
2778  * @write: %TRUE if this is a write to the sysctl file
2779  * @buffer: the user buffer
2780  * @lenp: the size of the user buffer
2781  * @ppos: file position
2782  *
2783  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2784  * values from/to the user buffer, treated as an ASCII string. The values
2785  * are treated as milliseconds, and converted to jiffies when they are stored.
2786  *
2787  * This routine will ensure the values are within the range specified by
2788  * table->extra1 (min) and table->extra2 (max).
2789  *
2790  * Returns 0 on success.
2791  */
2792 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2793 				      void __user *buffer,
2794 				      size_t *lenp, loff_t *ppos)
2795 {
2796     return do_proc_doulongvec_minmax(table, write, buffer,
2797 				     lenp, ppos, HZ, 1000l);
2798 }
2799 
2800 
2801 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2802 					 int *valp,
2803 					 int write, void *data)
2804 {
2805 	if (write) {
2806 		if (*lvalp > INT_MAX / HZ)
2807 			return 1;
2808 		*valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2809 	} else {
2810 		int val = *valp;
2811 		unsigned long lval;
2812 		if (val < 0) {
2813 			*negp = true;
2814 			lval = -(unsigned long)val;
2815 		} else {
2816 			*negp = false;
2817 			lval = (unsigned long)val;
2818 		}
2819 		*lvalp = lval / HZ;
2820 	}
2821 	return 0;
2822 }
2823 
2824 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2825 						int *valp,
2826 						int write, void *data)
2827 {
2828 	if (write) {
2829 		if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2830 			return 1;
2831 		*valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2832 	} else {
2833 		int val = *valp;
2834 		unsigned long lval;
2835 		if (val < 0) {
2836 			*negp = true;
2837 			lval = -(unsigned long)val;
2838 		} else {
2839 			*negp = false;
2840 			lval = (unsigned long)val;
2841 		}
2842 		*lvalp = jiffies_to_clock_t(lval);
2843 	}
2844 	return 0;
2845 }
2846 
2847 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2848 					    int *valp,
2849 					    int write, void *data)
2850 {
2851 	if (write) {
2852 		unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2853 
2854 		if (jif > INT_MAX)
2855 			return 1;
2856 		*valp = (int)jif;
2857 	} else {
2858 		int val = *valp;
2859 		unsigned long lval;
2860 		if (val < 0) {
2861 			*negp = true;
2862 			lval = -(unsigned long)val;
2863 		} else {
2864 			*negp = false;
2865 			lval = (unsigned long)val;
2866 		}
2867 		*lvalp = jiffies_to_msecs(lval);
2868 	}
2869 	return 0;
2870 }
2871 
2872 /**
2873  * proc_dointvec_jiffies - read a vector of integers as seconds
2874  * @table: the sysctl table
2875  * @write: %TRUE if this is a write to the sysctl file
2876  * @buffer: the user buffer
2877  * @lenp: the size of the user buffer
2878  * @ppos: file position
2879  *
2880  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2881  * values from/to the user buffer, treated as an ASCII string.
2882  * The values read are assumed to be in seconds, and are converted into
2883  * jiffies.
2884  *
2885  * Returns 0 on success.
2886  */
2887 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2888 			  void __user *buffer, size_t *lenp, loff_t *ppos)
2889 {
2890     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2891 		    	    do_proc_dointvec_jiffies_conv,NULL);
2892 }
2893 
2894 /**
2895  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2896  * @table: the sysctl table
2897  * @write: %TRUE if this is a write to the sysctl file
2898  * @buffer: the user buffer
2899  * @lenp: the size of the user buffer
2900  * @ppos: pointer to the file position
2901  *
2902  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2903  * values from/to the user buffer, treated as an ASCII string.
2904  * The values read are assumed to be in 1/USER_HZ seconds, and
2905  * are converted into jiffies.
2906  *
2907  * Returns 0 on success.
2908  */
2909 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2910 				 void __user *buffer, size_t *lenp, loff_t *ppos)
2911 {
2912     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2913 		    	    do_proc_dointvec_userhz_jiffies_conv,NULL);
2914 }
2915 
2916 /**
2917  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2918  * @table: the sysctl table
2919  * @write: %TRUE if this is a write to the sysctl file
2920  * @buffer: the user buffer
2921  * @lenp: the size of the user buffer
2922  * @ppos: file position
2923  * @ppos: the current position in the file
2924  *
2925  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2926  * values from/to the user buffer, treated as an ASCII string.
2927  * The values read are assumed to be in 1/1000 seconds, and
2928  * are converted into jiffies.
2929  *
2930  * Returns 0 on success.
2931  */
2932 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2933 			     void __user *buffer, size_t *lenp, loff_t *ppos)
2934 {
2935 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
2936 				do_proc_dointvec_ms_jiffies_conv, NULL);
2937 }
2938 
2939 static int proc_do_cad_pid(struct ctl_table *table, int write,
2940 			   void __user *buffer, size_t *lenp, loff_t *ppos)
2941 {
2942 	struct pid *new_pid;
2943 	pid_t tmp;
2944 	int r;
2945 
2946 	tmp = pid_vnr(cad_pid);
2947 
2948 	r = __do_proc_dointvec(&tmp, table, write, buffer,
2949 			       lenp, ppos, NULL, NULL);
2950 	if (r || !write)
2951 		return r;
2952 
2953 	new_pid = find_get_pid(tmp);
2954 	if (!new_pid)
2955 		return -ESRCH;
2956 
2957 	put_pid(xchg(&cad_pid, new_pid));
2958 	return 0;
2959 }
2960 
2961 /**
2962  * proc_do_large_bitmap - read/write from/to a large bitmap
2963  * @table: the sysctl table
2964  * @write: %TRUE if this is a write to the sysctl file
2965  * @buffer: the user buffer
2966  * @lenp: the size of the user buffer
2967  * @ppos: file position
2968  *
2969  * The bitmap is stored at table->data and the bitmap length (in bits)
2970  * in table->maxlen.
2971  *
2972  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2973  * large bitmaps may be represented in a compact manner. Writing into
2974  * the file will clear the bitmap then update it with the given input.
2975  *
2976  * Returns 0 on success.
2977  */
2978 int proc_do_large_bitmap(struct ctl_table *table, int write,
2979 			 void __user *buffer, size_t *lenp, loff_t *ppos)
2980 {
2981 	int err = 0;
2982 	bool first = 1;
2983 	size_t left = *lenp;
2984 	unsigned long bitmap_len = table->maxlen;
2985 	unsigned long *bitmap = *(unsigned long **) table->data;
2986 	unsigned long *tmp_bitmap = NULL;
2987 	char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
2988 
2989 	if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
2990 		*lenp = 0;
2991 		return 0;
2992 	}
2993 
2994 	if (write) {
2995 		char *kbuf, *p;
2996 
2997 		if (left > PAGE_SIZE - 1)
2998 			left = PAGE_SIZE - 1;
2999 
3000 		p = kbuf = memdup_user_nul(buffer, left);
3001 		if (IS_ERR(kbuf))
3002 			return PTR_ERR(kbuf);
3003 
3004 		tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
3005 				     GFP_KERNEL);
3006 		if (!tmp_bitmap) {
3007 			kfree(kbuf);
3008 			return -ENOMEM;
3009 		}
3010 		proc_skip_char(&p, &left, '\n');
3011 		while (!err && left) {
3012 			unsigned long val_a, val_b;
3013 			bool neg;
3014 
3015 			err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
3016 					     sizeof(tr_a), &c);
3017 			if (err)
3018 				break;
3019 			if (val_a >= bitmap_len || neg) {
3020 				err = -EINVAL;
3021 				break;
3022 			}
3023 
3024 			val_b = val_a;
3025 			if (left) {
3026 				p++;
3027 				left--;
3028 			}
3029 
3030 			if (c == '-') {
3031 				err = proc_get_long(&p, &left, &val_b,
3032 						     &neg, tr_b, sizeof(tr_b),
3033 						     &c);
3034 				if (err)
3035 					break;
3036 				if (val_b >= bitmap_len || neg ||
3037 				    val_a > val_b) {
3038 					err = -EINVAL;
3039 					break;
3040 				}
3041 				if (left) {
3042 					p++;
3043 					left--;
3044 				}
3045 			}
3046 
3047 			bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
3048 			first = 0;
3049 			proc_skip_char(&p, &left, '\n');
3050 		}
3051 		kfree(kbuf);
3052 	} else {
3053 		unsigned long bit_a, bit_b = 0;
3054 
3055 		while (left) {
3056 			bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
3057 			if (bit_a >= bitmap_len)
3058 				break;
3059 			bit_b = find_next_zero_bit(bitmap, bitmap_len,
3060 						   bit_a + 1) - 1;
3061 
3062 			if (!first) {
3063 				err = proc_put_char(&buffer, &left, ',');
3064 				if (err)
3065 					break;
3066 			}
3067 			err = proc_put_long(&buffer, &left, bit_a, false);
3068 			if (err)
3069 				break;
3070 			if (bit_a != bit_b) {
3071 				err = proc_put_char(&buffer, &left, '-');
3072 				if (err)
3073 					break;
3074 				err = proc_put_long(&buffer, &left, bit_b, false);
3075 				if (err)
3076 					break;
3077 			}
3078 
3079 			first = 0; bit_b++;
3080 		}
3081 		if (!err)
3082 			err = proc_put_char(&buffer, &left, '\n');
3083 	}
3084 
3085 	if (!err) {
3086 		if (write) {
3087 			if (*ppos)
3088 				bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
3089 			else
3090 				bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
3091 		}
3092 		kfree(tmp_bitmap);
3093 		*lenp -= left;
3094 		*ppos += *lenp;
3095 		return 0;
3096 	} else {
3097 		kfree(tmp_bitmap);
3098 		return err;
3099 	}
3100 }
3101 
3102 #else /* CONFIG_PROC_SYSCTL */
3103 
3104 int proc_dostring(struct ctl_table *table, int write,
3105 		  void __user *buffer, size_t *lenp, loff_t *ppos)
3106 {
3107 	return -ENOSYS;
3108 }
3109 
3110 int proc_dointvec(struct ctl_table *table, int write,
3111 		  void __user *buffer, size_t *lenp, loff_t *ppos)
3112 {
3113 	return -ENOSYS;
3114 }
3115 
3116 int proc_douintvec(struct ctl_table *table, int write,
3117 		  void __user *buffer, size_t *lenp, loff_t *ppos)
3118 {
3119 	return -ENOSYS;
3120 }
3121 
3122 int proc_dointvec_minmax(struct ctl_table *table, int write,
3123 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3124 {
3125 	return -ENOSYS;
3126 }
3127 
3128 int proc_douintvec_minmax(struct ctl_table *table, int write,
3129 			  void __user *buffer, size_t *lenp, loff_t *ppos)
3130 {
3131 	return -ENOSYS;
3132 }
3133 
3134 int proc_dointvec_jiffies(struct ctl_table *table, int write,
3135 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3136 {
3137 	return -ENOSYS;
3138 }
3139 
3140 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
3141 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3142 {
3143 	return -ENOSYS;
3144 }
3145 
3146 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
3147 			     void __user *buffer, size_t *lenp, loff_t *ppos)
3148 {
3149 	return -ENOSYS;
3150 }
3151 
3152 int proc_doulongvec_minmax(struct ctl_table *table, int write,
3153 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3154 {
3155 	return -ENOSYS;
3156 }
3157 
3158 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
3159 				      void __user *buffer,
3160 				      size_t *lenp, loff_t *ppos)
3161 {
3162     return -ENOSYS;
3163 }
3164 
3165 
3166 #endif /* CONFIG_PROC_SYSCTL */
3167 
3168 /*
3169  * No sense putting this after each symbol definition, twice,
3170  * exception granted :-)
3171  */
3172 EXPORT_SYMBOL(proc_dointvec);
3173 EXPORT_SYMBOL(proc_douintvec);
3174 EXPORT_SYMBOL(proc_dointvec_jiffies);
3175 EXPORT_SYMBOL(proc_dointvec_minmax);
3176 EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
3177 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3178 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3179 EXPORT_SYMBOL(proc_dostring);
3180 EXPORT_SYMBOL(proc_doulongvec_minmax);
3181 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3182