xref: /linux/kernel/sysctl.c (revision c6ed444fd6fffaaf2e3857d926ed18bf3df81e8e)
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/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 #include <linux/sched/coredump.h>
66 #include <linux/kexec.h>
67 #include <linux/bpf.h>
68 #include <linux/mount.h>
69 #include <linux/pipe_fs_i.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 static int proc_dopipe_max_size(struct ctl_table *table, int write,
222 		void __user *buffer, size_t *lenp, loff_t *ppos);
223 
224 #ifdef CONFIG_MAGIC_SYSRQ
225 /* Note: sysrq code uses it's own private copy */
226 static int __sysrq_enabled = CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE;
227 
228 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
229 				void __user *buffer, size_t *lenp,
230 				loff_t *ppos)
231 {
232 	int error;
233 
234 	error = proc_dointvec(table, write, buffer, lenp, ppos);
235 	if (error)
236 		return error;
237 
238 	if (write)
239 		sysrq_toggle_support(__sysrq_enabled);
240 
241 	return 0;
242 }
243 
244 #endif
245 
246 static struct ctl_table kern_table[];
247 static struct ctl_table vm_table[];
248 static struct ctl_table fs_table[];
249 static struct ctl_table debug_table[];
250 static struct ctl_table dev_table[];
251 extern struct ctl_table random_table[];
252 #ifdef CONFIG_EPOLL
253 extern struct ctl_table epoll_table[];
254 #endif
255 
256 #ifdef CONFIG_FW_LOADER_USER_HELPER
257 extern struct ctl_table firmware_config_table[];
258 #endif
259 
260 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
261 int sysctl_legacy_va_layout;
262 #endif
263 
264 /* The default sysctl tables: */
265 
266 static struct ctl_table sysctl_base_table[] = {
267 	{
268 		.procname	= "kernel",
269 		.mode		= 0555,
270 		.child		= kern_table,
271 	},
272 	{
273 		.procname	= "vm",
274 		.mode		= 0555,
275 		.child		= vm_table,
276 	},
277 	{
278 		.procname	= "fs",
279 		.mode		= 0555,
280 		.child		= fs_table,
281 	},
282 	{
283 		.procname	= "debug",
284 		.mode		= 0555,
285 		.child		= debug_table,
286 	},
287 	{
288 		.procname	= "dev",
289 		.mode		= 0555,
290 		.child		= dev_table,
291 	},
292 	{ }
293 };
294 
295 #ifdef CONFIG_SCHED_DEBUG
296 static int min_sched_granularity_ns = 100000;		/* 100 usecs */
297 static int max_sched_granularity_ns = NSEC_PER_SEC;	/* 1 second */
298 static int min_wakeup_granularity_ns;			/* 0 usecs */
299 static int max_wakeup_granularity_ns = NSEC_PER_SEC;	/* 1 second */
300 #ifdef CONFIG_SMP
301 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
302 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
303 #endif /* CONFIG_SMP */
304 #endif /* CONFIG_SCHED_DEBUG */
305 
306 #ifdef CONFIG_COMPACTION
307 static int min_extfrag_threshold;
308 static int max_extfrag_threshold = 1000;
309 #endif
310 
311 static struct ctl_table kern_table[] = {
312 	{
313 		.procname	= "sched_child_runs_first",
314 		.data		= &sysctl_sched_child_runs_first,
315 		.maxlen		= sizeof(unsigned int),
316 		.mode		= 0644,
317 		.proc_handler	= proc_dointvec,
318 	},
319 #ifdef CONFIG_SCHED_DEBUG
320 	{
321 		.procname	= "sched_min_granularity_ns",
322 		.data		= &sysctl_sched_min_granularity,
323 		.maxlen		= sizeof(unsigned int),
324 		.mode		= 0644,
325 		.proc_handler	= sched_proc_update_handler,
326 		.extra1		= &min_sched_granularity_ns,
327 		.extra2		= &max_sched_granularity_ns,
328 	},
329 	{
330 		.procname	= "sched_latency_ns",
331 		.data		= &sysctl_sched_latency,
332 		.maxlen		= sizeof(unsigned int),
333 		.mode		= 0644,
334 		.proc_handler	= sched_proc_update_handler,
335 		.extra1		= &min_sched_granularity_ns,
336 		.extra2		= &max_sched_granularity_ns,
337 	},
338 	{
339 		.procname	= "sched_wakeup_granularity_ns",
340 		.data		= &sysctl_sched_wakeup_granularity,
341 		.maxlen		= sizeof(unsigned int),
342 		.mode		= 0644,
343 		.proc_handler	= sched_proc_update_handler,
344 		.extra1		= &min_wakeup_granularity_ns,
345 		.extra2		= &max_wakeup_granularity_ns,
346 	},
347 #ifdef CONFIG_SMP
348 	{
349 		.procname	= "sched_tunable_scaling",
350 		.data		= &sysctl_sched_tunable_scaling,
351 		.maxlen		= sizeof(enum sched_tunable_scaling),
352 		.mode		= 0644,
353 		.proc_handler	= sched_proc_update_handler,
354 		.extra1		= &min_sched_tunable_scaling,
355 		.extra2		= &max_sched_tunable_scaling,
356 	},
357 	{
358 		.procname	= "sched_migration_cost_ns",
359 		.data		= &sysctl_sched_migration_cost,
360 		.maxlen		= sizeof(unsigned int),
361 		.mode		= 0644,
362 		.proc_handler	= proc_dointvec,
363 	},
364 	{
365 		.procname	= "sched_nr_migrate",
366 		.data		= &sysctl_sched_nr_migrate,
367 		.maxlen		= sizeof(unsigned int),
368 		.mode		= 0644,
369 		.proc_handler	= proc_dointvec,
370 	},
371 #ifdef CONFIG_SCHEDSTATS
372 	{
373 		.procname	= "sched_schedstats",
374 		.data		= NULL,
375 		.maxlen		= sizeof(unsigned int),
376 		.mode		= 0644,
377 		.proc_handler	= sysctl_schedstats,
378 		.extra1		= &zero,
379 		.extra2		= &one,
380 	},
381 #endif /* CONFIG_SCHEDSTATS */
382 #endif /* CONFIG_SMP */
383 #ifdef CONFIG_NUMA_BALANCING
384 	{
385 		.procname	= "numa_balancing_scan_delay_ms",
386 		.data		= &sysctl_numa_balancing_scan_delay,
387 		.maxlen		= sizeof(unsigned int),
388 		.mode		= 0644,
389 		.proc_handler	= proc_dointvec,
390 	},
391 	{
392 		.procname	= "numa_balancing_scan_period_min_ms",
393 		.data		= &sysctl_numa_balancing_scan_period_min,
394 		.maxlen		= sizeof(unsigned int),
395 		.mode		= 0644,
396 		.proc_handler	= proc_dointvec,
397 	},
398 	{
399 		.procname	= "numa_balancing_scan_period_max_ms",
400 		.data		= &sysctl_numa_balancing_scan_period_max,
401 		.maxlen		= sizeof(unsigned int),
402 		.mode		= 0644,
403 		.proc_handler	= proc_dointvec,
404 	},
405 	{
406 		.procname	= "numa_balancing_scan_size_mb",
407 		.data		= &sysctl_numa_balancing_scan_size,
408 		.maxlen		= sizeof(unsigned int),
409 		.mode		= 0644,
410 		.proc_handler	= proc_dointvec_minmax,
411 		.extra1		= &one,
412 	},
413 	{
414 		.procname	= "numa_balancing",
415 		.data		= NULL, /* filled in by handler */
416 		.maxlen		= sizeof(unsigned int),
417 		.mode		= 0644,
418 		.proc_handler	= sysctl_numa_balancing,
419 		.extra1		= &zero,
420 		.extra2		= &one,
421 	},
422 #endif /* CONFIG_NUMA_BALANCING */
423 #endif /* CONFIG_SCHED_DEBUG */
424 	{
425 		.procname	= "sched_rt_period_us",
426 		.data		= &sysctl_sched_rt_period,
427 		.maxlen		= sizeof(unsigned int),
428 		.mode		= 0644,
429 		.proc_handler	= sched_rt_handler,
430 	},
431 	{
432 		.procname	= "sched_rt_runtime_us",
433 		.data		= &sysctl_sched_rt_runtime,
434 		.maxlen		= sizeof(int),
435 		.mode		= 0644,
436 		.proc_handler	= sched_rt_handler,
437 	},
438 	{
439 		.procname	= "sched_rr_timeslice_ms",
440 		.data		= &sysctl_sched_rr_timeslice,
441 		.maxlen		= sizeof(int),
442 		.mode		= 0644,
443 		.proc_handler	= sched_rr_handler,
444 	},
445 #ifdef CONFIG_SCHED_AUTOGROUP
446 	{
447 		.procname	= "sched_autogroup_enabled",
448 		.data		= &sysctl_sched_autogroup_enabled,
449 		.maxlen		= sizeof(unsigned int),
450 		.mode		= 0644,
451 		.proc_handler	= proc_dointvec_minmax,
452 		.extra1		= &zero,
453 		.extra2		= &one,
454 	},
455 #endif
456 #ifdef CONFIG_CFS_BANDWIDTH
457 	{
458 		.procname	= "sched_cfs_bandwidth_slice_us",
459 		.data		= &sysctl_sched_cfs_bandwidth_slice,
460 		.maxlen		= sizeof(unsigned int),
461 		.mode		= 0644,
462 		.proc_handler	= proc_dointvec_minmax,
463 		.extra1		= &one,
464 	},
465 #endif
466 #ifdef CONFIG_PROVE_LOCKING
467 	{
468 		.procname	= "prove_locking",
469 		.data		= &prove_locking,
470 		.maxlen		= sizeof(int),
471 		.mode		= 0644,
472 		.proc_handler	= proc_dointvec,
473 	},
474 #endif
475 #ifdef CONFIG_LOCK_STAT
476 	{
477 		.procname	= "lock_stat",
478 		.data		= &lock_stat,
479 		.maxlen		= sizeof(int),
480 		.mode		= 0644,
481 		.proc_handler	= proc_dointvec,
482 	},
483 #endif
484 	{
485 		.procname	= "panic",
486 		.data		= &panic_timeout,
487 		.maxlen		= sizeof(int),
488 		.mode		= 0644,
489 		.proc_handler	= proc_dointvec,
490 	},
491 #ifdef CONFIG_COREDUMP
492 	{
493 		.procname	= "core_uses_pid",
494 		.data		= &core_uses_pid,
495 		.maxlen		= sizeof(int),
496 		.mode		= 0644,
497 		.proc_handler	= proc_dointvec,
498 	},
499 	{
500 		.procname	= "core_pattern",
501 		.data		= core_pattern,
502 		.maxlen		= CORENAME_MAX_SIZE,
503 		.mode		= 0644,
504 		.proc_handler	= proc_dostring_coredump,
505 	},
506 	{
507 		.procname	= "core_pipe_limit",
508 		.data		= &core_pipe_limit,
509 		.maxlen		= sizeof(unsigned int),
510 		.mode		= 0644,
511 		.proc_handler	= proc_dointvec,
512 	},
513 #endif
514 #ifdef CONFIG_PROC_SYSCTL
515 	{
516 		.procname	= "tainted",
517 		.maxlen 	= sizeof(long),
518 		.mode		= 0644,
519 		.proc_handler	= proc_taint,
520 	},
521 	{
522 		.procname	= "sysctl_writes_strict",
523 		.data		= &sysctl_writes_strict,
524 		.maxlen		= sizeof(int),
525 		.mode		= 0644,
526 		.proc_handler	= proc_dointvec_minmax,
527 		.extra1		= &neg_one,
528 		.extra2		= &one,
529 	},
530 #endif
531 #ifdef CONFIG_LATENCYTOP
532 	{
533 		.procname	= "latencytop",
534 		.data		= &latencytop_enabled,
535 		.maxlen		= sizeof(int),
536 		.mode		= 0644,
537 		.proc_handler	= sysctl_latencytop,
538 	},
539 #endif
540 #ifdef CONFIG_BLK_DEV_INITRD
541 	{
542 		.procname	= "real-root-dev",
543 		.data		= &real_root_dev,
544 		.maxlen		= sizeof(int),
545 		.mode		= 0644,
546 		.proc_handler	= proc_dointvec,
547 	},
548 #endif
549 	{
550 		.procname	= "print-fatal-signals",
551 		.data		= &print_fatal_signals,
552 		.maxlen		= sizeof(int),
553 		.mode		= 0644,
554 		.proc_handler	= proc_dointvec,
555 	},
556 #ifdef CONFIG_SPARC
557 	{
558 		.procname	= "reboot-cmd",
559 		.data		= reboot_command,
560 		.maxlen		= 256,
561 		.mode		= 0644,
562 		.proc_handler	= proc_dostring,
563 	},
564 	{
565 		.procname	= "stop-a",
566 		.data		= &stop_a_enabled,
567 		.maxlen		= sizeof (int),
568 		.mode		= 0644,
569 		.proc_handler	= proc_dointvec,
570 	},
571 	{
572 		.procname	= "scons-poweroff",
573 		.data		= &scons_pwroff,
574 		.maxlen		= sizeof (int),
575 		.mode		= 0644,
576 		.proc_handler	= proc_dointvec,
577 	},
578 #endif
579 #ifdef CONFIG_SPARC64
580 	{
581 		.procname	= "tsb-ratio",
582 		.data		= &sysctl_tsb_ratio,
583 		.maxlen		= sizeof (int),
584 		.mode		= 0644,
585 		.proc_handler	= proc_dointvec,
586 	},
587 #endif
588 #ifdef __hppa__
589 	{
590 		.procname	= "soft-power",
591 		.data		= &pwrsw_enabled,
592 		.maxlen		= sizeof (int),
593 	 	.mode		= 0644,
594 		.proc_handler	= proc_dointvec,
595 	},
596 #endif
597 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
598 	{
599 		.procname	= "unaligned-trap",
600 		.data		= &unaligned_enabled,
601 		.maxlen		= sizeof (int),
602 		.mode		= 0644,
603 		.proc_handler	= proc_dointvec,
604 	},
605 #endif
606 	{
607 		.procname	= "ctrl-alt-del",
608 		.data		= &C_A_D,
609 		.maxlen		= sizeof(int),
610 		.mode		= 0644,
611 		.proc_handler	= proc_dointvec,
612 	},
613 #ifdef CONFIG_FUNCTION_TRACER
614 	{
615 		.procname	= "ftrace_enabled",
616 		.data		= &ftrace_enabled,
617 		.maxlen		= sizeof(int),
618 		.mode		= 0644,
619 		.proc_handler	= ftrace_enable_sysctl,
620 	},
621 #endif
622 #ifdef CONFIG_STACK_TRACER
623 	{
624 		.procname	= "stack_tracer_enabled",
625 		.data		= &stack_tracer_enabled,
626 		.maxlen		= sizeof(int),
627 		.mode		= 0644,
628 		.proc_handler	= stack_trace_sysctl,
629 	},
630 #endif
631 #ifdef CONFIG_TRACING
632 	{
633 		.procname	= "ftrace_dump_on_oops",
634 		.data		= &ftrace_dump_on_oops,
635 		.maxlen		= sizeof(int),
636 		.mode		= 0644,
637 		.proc_handler	= proc_dointvec,
638 	},
639 	{
640 		.procname	= "traceoff_on_warning",
641 		.data		= &__disable_trace_on_warning,
642 		.maxlen		= sizeof(__disable_trace_on_warning),
643 		.mode		= 0644,
644 		.proc_handler	= proc_dointvec,
645 	},
646 	{
647 		.procname	= "tracepoint_printk",
648 		.data		= &tracepoint_printk,
649 		.maxlen		= sizeof(tracepoint_printk),
650 		.mode		= 0644,
651 		.proc_handler	= tracepoint_printk_sysctl,
652 	},
653 #endif
654 #ifdef CONFIG_KEXEC_CORE
655 	{
656 		.procname	= "kexec_load_disabled",
657 		.data		= &kexec_load_disabled,
658 		.maxlen		= sizeof(int),
659 		.mode		= 0644,
660 		/* only handle a transition from default "0" to "1" */
661 		.proc_handler	= proc_dointvec_minmax,
662 		.extra1		= &one,
663 		.extra2		= &one,
664 	},
665 #endif
666 #ifdef CONFIG_MODULES
667 	{
668 		.procname	= "modprobe",
669 		.data		= &modprobe_path,
670 		.maxlen		= KMOD_PATH_LEN,
671 		.mode		= 0644,
672 		.proc_handler	= proc_dostring,
673 	},
674 	{
675 		.procname	= "modules_disabled",
676 		.data		= &modules_disabled,
677 		.maxlen		= sizeof(int),
678 		.mode		= 0644,
679 		/* only handle a transition from default "0" to "1" */
680 		.proc_handler	= proc_dointvec_minmax,
681 		.extra1		= &one,
682 		.extra2		= &one,
683 	},
684 #endif
685 #ifdef CONFIG_UEVENT_HELPER
686 	{
687 		.procname	= "hotplug",
688 		.data		= &uevent_helper,
689 		.maxlen		= UEVENT_HELPER_PATH_LEN,
690 		.mode		= 0644,
691 		.proc_handler	= proc_dostring,
692 	},
693 #endif
694 #ifdef CONFIG_CHR_DEV_SG
695 	{
696 		.procname	= "sg-big-buff",
697 		.data		= &sg_big_buff,
698 		.maxlen		= sizeof (int),
699 		.mode		= 0444,
700 		.proc_handler	= proc_dointvec,
701 	},
702 #endif
703 #ifdef CONFIG_BSD_PROCESS_ACCT
704 	{
705 		.procname	= "acct",
706 		.data		= &acct_parm,
707 		.maxlen		= 3*sizeof(int),
708 		.mode		= 0644,
709 		.proc_handler	= proc_dointvec,
710 	},
711 #endif
712 #ifdef CONFIG_MAGIC_SYSRQ
713 	{
714 		.procname	= "sysrq",
715 		.data		= &__sysrq_enabled,
716 		.maxlen		= sizeof (int),
717 		.mode		= 0644,
718 		.proc_handler	= sysrq_sysctl_handler,
719 	},
720 #endif
721 #ifdef CONFIG_PROC_SYSCTL
722 	{
723 		.procname	= "cad_pid",
724 		.data		= NULL,
725 		.maxlen		= sizeof (int),
726 		.mode		= 0600,
727 		.proc_handler	= proc_do_cad_pid,
728 	},
729 #endif
730 	{
731 		.procname	= "threads-max",
732 		.data		= NULL,
733 		.maxlen		= sizeof(int),
734 		.mode		= 0644,
735 		.proc_handler	= sysctl_max_threads,
736 	},
737 	{
738 		.procname	= "random",
739 		.mode		= 0555,
740 		.child		= random_table,
741 	},
742 	{
743 		.procname	= "usermodehelper",
744 		.mode		= 0555,
745 		.child		= usermodehelper_table,
746 	},
747 #ifdef CONFIG_FW_LOADER_USER_HELPER
748 	{
749 		.procname	= "firmware_config",
750 		.mode		= 0555,
751 		.child		= firmware_config_table,
752 	},
753 #endif
754 	{
755 		.procname	= "overflowuid",
756 		.data		= &overflowuid,
757 		.maxlen		= sizeof(int),
758 		.mode		= 0644,
759 		.proc_handler	= proc_dointvec_minmax,
760 		.extra1		= &minolduid,
761 		.extra2		= &maxolduid,
762 	},
763 	{
764 		.procname	= "overflowgid",
765 		.data		= &overflowgid,
766 		.maxlen		= sizeof(int),
767 		.mode		= 0644,
768 		.proc_handler	= proc_dointvec_minmax,
769 		.extra1		= &minolduid,
770 		.extra2		= &maxolduid,
771 	},
772 #ifdef CONFIG_S390
773 #ifdef CONFIG_MATHEMU
774 	{
775 		.procname	= "ieee_emulation_warnings",
776 		.data		= &sysctl_ieee_emulation_warnings,
777 		.maxlen		= sizeof(int),
778 		.mode		= 0644,
779 		.proc_handler	= proc_dointvec,
780 	},
781 #endif
782 	{
783 		.procname	= "userprocess_debug",
784 		.data		= &show_unhandled_signals,
785 		.maxlen		= sizeof(int),
786 		.mode		= 0644,
787 		.proc_handler	= proc_dointvec,
788 	},
789 #endif
790 	{
791 		.procname	= "pid_max",
792 		.data		= &pid_max,
793 		.maxlen		= sizeof (int),
794 		.mode		= 0644,
795 		.proc_handler	= proc_dointvec_minmax,
796 		.extra1		= &pid_max_min,
797 		.extra2		= &pid_max_max,
798 	},
799 	{
800 		.procname	= "panic_on_oops",
801 		.data		= &panic_on_oops,
802 		.maxlen		= sizeof(int),
803 		.mode		= 0644,
804 		.proc_handler	= proc_dointvec,
805 	},
806 #if defined CONFIG_PRINTK
807 	{
808 		.procname	= "printk",
809 		.data		= &console_loglevel,
810 		.maxlen		= 4*sizeof(int),
811 		.mode		= 0644,
812 		.proc_handler	= proc_dointvec,
813 	},
814 	{
815 		.procname	= "printk_ratelimit",
816 		.data		= &printk_ratelimit_state.interval,
817 		.maxlen		= sizeof(int),
818 		.mode		= 0644,
819 		.proc_handler	= proc_dointvec_jiffies,
820 	},
821 	{
822 		.procname	= "printk_ratelimit_burst",
823 		.data		= &printk_ratelimit_state.burst,
824 		.maxlen		= sizeof(int),
825 		.mode		= 0644,
826 		.proc_handler	= proc_dointvec,
827 	},
828 	{
829 		.procname	= "printk_delay",
830 		.data		= &printk_delay_msec,
831 		.maxlen		= sizeof(int),
832 		.mode		= 0644,
833 		.proc_handler	= proc_dointvec_minmax,
834 		.extra1		= &zero,
835 		.extra2		= &ten_thousand,
836 	},
837 	{
838 		.procname	= "printk_devkmsg",
839 		.data		= devkmsg_log_str,
840 		.maxlen		= DEVKMSG_STR_MAX_SIZE,
841 		.mode		= 0644,
842 		.proc_handler	= devkmsg_sysctl_set_loglvl,
843 	},
844 	{
845 		.procname	= "dmesg_restrict",
846 		.data		= &dmesg_restrict,
847 		.maxlen		= sizeof(int),
848 		.mode		= 0644,
849 		.proc_handler	= proc_dointvec_minmax_sysadmin,
850 		.extra1		= &zero,
851 		.extra2		= &one,
852 	},
853 	{
854 		.procname	= "kptr_restrict",
855 		.data		= &kptr_restrict,
856 		.maxlen		= sizeof(int),
857 		.mode		= 0644,
858 		.proc_handler	= proc_dointvec_minmax_sysadmin,
859 		.extra1		= &zero,
860 		.extra2		= &two,
861 	},
862 #endif
863 	{
864 		.procname	= "ngroups_max",
865 		.data		= &ngroups_max,
866 		.maxlen		= sizeof (int),
867 		.mode		= 0444,
868 		.proc_handler	= proc_dointvec,
869 	},
870 	{
871 		.procname	= "cap_last_cap",
872 		.data		= (void *)&cap_last_cap,
873 		.maxlen		= sizeof(int),
874 		.mode		= 0444,
875 		.proc_handler	= proc_dointvec,
876 	},
877 #if defined(CONFIG_LOCKUP_DETECTOR)
878 	{
879 		.procname       = "watchdog",
880 		.data		= &watchdog_user_enabled,
881 		.maxlen		= sizeof(int),
882 		.mode		= 0644,
883 		.proc_handler   = proc_watchdog,
884 		.extra1		= &zero,
885 		.extra2		= &one,
886 	},
887 	{
888 		.procname	= "watchdog_thresh",
889 		.data		= &watchdog_thresh,
890 		.maxlen		= sizeof(int),
891 		.mode		= 0644,
892 		.proc_handler	= proc_watchdog_thresh,
893 		.extra1		= &zero,
894 		.extra2		= &sixty,
895 	},
896 	{
897 		.procname       = "nmi_watchdog",
898 		.data		= &nmi_watchdog_user_enabled,
899 		.maxlen		= sizeof(int),
900 		.mode		= NMI_WATCHDOG_SYSCTL_PERM,
901 		.proc_handler   = proc_nmi_watchdog,
902 		.extra1		= &zero,
903 		.extra2		= &one,
904 	},
905 	{
906 		.procname	= "watchdog_cpumask",
907 		.data		= &watchdog_cpumask_bits,
908 		.maxlen		= NR_CPUS,
909 		.mode		= 0644,
910 		.proc_handler	= proc_watchdog_cpumask,
911 	},
912 #ifdef CONFIG_SOFTLOCKUP_DETECTOR
913 	{
914 		.procname       = "soft_watchdog",
915 		.data		= &soft_watchdog_user_enabled,
916 		.maxlen		= sizeof(int),
917 		.mode		= 0644,
918 		.proc_handler   = proc_soft_watchdog,
919 		.extra1		= &zero,
920 		.extra2		= &one,
921 	},
922 	{
923 		.procname	= "softlockup_panic",
924 		.data		= &softlockup_panic,
925 		.maxlen		= sizeof(int),
926 		.mode		= 0644,
927 		.proc_handler	= proc_dointvec_minmax,
928 		.extra1		= &zero,
929 		.extra2		= &one,
930 	},
931 #ifdef CONFIG_SMP
932 	{
933 		.procname	= "softlockup_all_cpu_backtrace",
934 		.data		= &sysctl_softlockup_all_cpu_backtrace,
935 		.maxlen		= sizeof(int),
936 		.mode		= 0644,
937 		.proc_handler	= proc_dointvec_minmax,
938 		.extra1		= &zero,
939 		.extra2		= &one,
940 	},
941 #endif /* CONFIG_SMP */
942 #endif
943 #ifdef CONFIG_HARDLOCKUP_DETECTOR
944 	{
945 		.procname	= "hardlockup_panic",
946 		.data		= &hardlockup_panic,
947 		.maxlen		= sizeof(int),
948 		.mode		= 0644,
949 		.proc_handler	= proc_dointvec_minmax,
950 		.extra1		= &zero,
951 		.extra2		= &one,
952 	},
953 #ifdef CONFIG_SMP
954 	{
955 		.procname	= "hardlockup_all_cpu_backtrace",
956 		.data		= &sysctl_hardlockup_all_cpu_backtrace,
957 		.maxlen		= sizeof(int),
958 		.mode		= 0644,
959 		.proc_handler	= proc_dointvec_minmax,
960 		.extra1		= &zero,
961 		.extra2		= &one,
962 	},
963 #endif /* CONFIG_SMP */
964 #endif
965 #endif
966 
967 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
968 	{
969 		.procname       = "unknown_nmi_panic",
970 		.data           = &unknown_nmi_panic,
971 		.maxlen         = sizeof (int),
972 		.mode           = 0644,
973 		.proc_handler   = proc_dointvec,
974 	},
975 #endif
976 #if defined(CONFIG_X86)
977 	{
978 		.procname	= "panic_on_unrecovered_nmi",
979 		.data		= &panic_on_unrecovered_nmi,
980 		.maxlen		= sizeof(int),
981 		.mode		= 0644,
982 		.proc_handler	= proc_dointvec,
983 	},
984 	{
985 		.procname	= "panic_on_io_nmi",
986 		.data		= &panic_on_io_nmi,
987 		.maxlen		= sizeof(int),
988 		.mode		= 0644,
989 		.proc_handler	= proc_dointvec,
990 	},
991 #ifdef CONFIG_DEBUG_STACKOVERFLOW
992 	{
993 		.procname	= "panic_on_stackoverflow",
994 		.data		= &sysctl_panic_on_stackoverflow,
995 		.maxlen		= sizeof(int),
996 		.mode		= 0644,
997 		.proc_handler	= proc_dointvec,
998 	},
999 #endif
1000 	{
1001 		.procname	= "bootloader_type",
1002 		.data		= &bootloader_type,
1003 		.maxlen		= sizeof (int),
1004 		.mode		= 0444,
1005 		.proc_handler	= proc_dointvec,
1006 	},
1007 	{
1008 		.procname	= "bootloader_version",
1009 		.data		= &bootloader_version,
1010 		.maxlen		= sizeof (int),
1011 		.mode		= 0444,
1012 		.proc_handler	= proc_dointvec,
1013 	},
1014 	{
1015 		.procname	= "io_delay_type",
1016 		.data		= &io_delay_type,
1017 		.maxlen		= sizeof(int),
1018 		.mode		= 0644,
1019 		.proc_handler	= proc_dointvec,
1020 	},
1021 #endif
1022 #if defined(CONFIG_MMU)
1023 	{
1024 		.procname	= "randomize_va_space",
1025 		.data		= &randomize_va_space,
1026 		.maxlen		= sizeof(int),
1027 		.mode		= 0644,
1028 		.proc_handler	= proc_dointvec,
1029 	},
1030 #endif
1031 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1032 	{
1033 		.procname	= "spin_retry",
1034 		.data		= &spin_retry,
1035 		.maxlen		= sizeof (int),
1036 		.mode		= 0644,
1037 		.proc_handler	= proc_dointvec,
1038 	},
1039 #endif
1040 #if	defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1041 	{
1042 		.procname	= "acpi_video_flags",
1043 		.data		= &acpi_realmode_flags,
1044 		.maxlen		= sizeof (unsigned long),
1045 		.mode		= 0644,
1046 		.proc_handler	= proc_doulongvec_minmax,
1047 	},
1048 #endif
1049 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1050 	{
1051 		.procname	= "ignore-unaligned-usertrap",
1052 		.data		= &no_unaligned_warning,
1053 		.maxlen		= sizeof (int),
1054 	 	.mode		= 0644,
1055 		.proc_handler	= proc_dointvec,
1056 	},
1057 #endif
1058 #ifdef CONFIG_IA64
1059 	{
1060 		.procname	= "unaligned-dump-stack",
1061 		.data		= &unaligned_dump_stack,
1062 		.maxlen		= sizeof (int),
1063 		.mode		= 0644,
1064 		.proc_handler	= proc_dointvec,
1065 	},
1066 #endif
1067 #ifdef CONFIG_DETECT_HUNG_TASK
1068 	{
1069 		.procname	= "hung_task_panic",
1070 		.data		= &sysctl_hung_task_panic,
1071 		.maxlen		= sizeof(int),
1072 		.mode		= 0644,
1073 		.proc_handler	= proc_dointvec_minmax,
1074 		.extra1		= &zero,
1075 		.extra2		= &one,
1076 	},
1077 	{
1078 		.procname	= "hung_task_check_count",
1079 		.data		= &sysctl_hung_task_check_count,
1080 		.maxlen		= sizeof(int),
1081 		.mode		= 0644,
1082 		.proc_handler	= proc_dointvec_minmax,
1083 		.extra1		= &zero,
1084 	},
1085 	{
1086 		.procname	= "hung_task_timeout_secs",
1087 		.data		= &sysctl_hung_task_timeout_secs,
1088 		.maxlen		= sizeof(unsigned long),
1089 		.mode		= 0644,
1090 		.proc_handler	= proc_dohung_task_timeout_secs,
1091 		.extra2		= &hung_task_timeout_max,
1092 	},
1093 	{
1094 		.procname	= "hung_task_warnings",
1095 		.data		= &sysctl_hung_task_warnings,
1096 		.maxlen		= sizeof(int),
1097 		.mode		= 0644,
1098 		.proc_handler	= proc_dointvec_minmax,
1099 		.extra1		= &neg_one,
1100 	},
1101 #endif
1102 #ifdef CONFIG_RT_MUTEXES
1103 	{
1104 		.procname	= "max_lock_depth",
1105 		.data		= &max_lock_depth,
1106 		.maxlen		= sizeof(int),
1107 		.mode		= 0644,
1108 		.proc_handler	= proc_dointvec,
1109 	},
1110 #endif
1111 	{
1112 		.procname	= "poweroff_cmd",
1113 		.data		= &poweroff_cmd,
1114 		.maxlen		= POWEROFF_CMD_PATH_LEN,
1115 		.mode		= 0644,
1116 		.proc_handler	= proc_dostring,
1117 	},
1118 #ifdef CONFIG_KEYS
1119 	{
1120 		.procname	= "keys",
1121 		.mode		= 0555,
1122 		.child		= key_sysctls,
1123 	},
1124 #endif
1125 #ifdef CONFIG_PERF_EVENTS
1126 	/*
1127 	 * User-space scripts rely on the existence of this file
1128 	 * as a feature check for perf_events being enabled.
1129 	 *
1130 	 * So it's an ABI, do not remove!
1131 	 */
1132 	{
1133 		.procname	= "perf_event_paranoid",
1134 		.data		= &sysctl_perf_event_paranoid,
1135 		.maxlen		= sizeof(sysctl_perf_event_paranoid),
1136 		.mode		= 0644,
1137 		.proc_handler	= proc_dointvec,
1138 	},
1139 	{
1140 		.procname	= "perf_event_mlock_kb",
1141 		.data		= &sysctl_perf_event_mlock,
1142 		.maxlen		= sizeof(sysctl_perf_event_mlock),
1143 		.mode		= 0644,
1144 		.proc_handler	= proc_dointvec,
1145 	},
1146 	{
1147 		.procname	= "perf_event_max_sample_rate",
1148 		.data		= &sysctl_perf_event_sample_rate,
1149 		.maxlen		= sizeof(sysctl_perf_event_sample_rate),
1150 		.mode		= 0644,
1151 		.proc_handler	= perf_proc_update_handler,
1152 		.extra1		= &one,
1153 	},
1154 	{
1155 		.procname	= "perf_cpu_time_max_percent",
1156 		.data		= &sysctl_perf_cpu_time_max_percent,
1157 		.maxlen		= sizeof(sysctl_perf_cpu_time_max_percent),
1158 		.mode		= 0644,
1159 		.proc_handler	= perf_cpu_time_max_percent_handler,
1160 		.extra1		= &zero,
1161 		.extra2		= &one_hundred,
1162 	},
1163 	{
1164 		.procname	= "perf_event_max_stack",
1165 		.data		= &sysctl_perf_event_max_stack,
1166 		.maxlen		= sizeof(sysctl_perf_event_max_stack),
1167 		.mode		= 0644,
1168 		.proc_handler	= perf_event_max_stack_handler,
1169 		.extra1		= &zero,
1170 		.extra2		= &six_hundred_forty_kb,
1171 	},
1172 	{
1173 		.procname	= "perf_event_max_contexts_per_stack",
1174 		.data		= &sysctl_perf_event_max_contexts_per_stack,
1175 		.maxlen		= sizeof(sysctl_perf_event_max_contexts_per_stack),
1176 		.mode		= 0644,
1177 		.proc_handler	= perf_event_max_stack_handler,
1178 		.extra1		= &zero,
1179 		.extra2		= &one_thousand,
1180 	},
1181 #endif
1182 	{
1183 		.procname	= "panic_on_warn",
1184 		.data		= &panic_on_warn,
1185 		.maxlen		= sizeof(int),
1186 		.mode		= 0644,
1187 		.proc_handler	= proc_dointvec_minmax,
1188 		.extra1		= &zero,
1189 		.extra2		= &one,
1190 	},
1191 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1192 	{
1193 		.procname	= "timer_migration",
1194 		.data		= &sysctl_timer_migration,
1195 		.maxlen		= sizeof(unsigned int),
1196 		.mode		= 0644,
1197 		.proc_handler	= timer_migration_handler,
1198 		.extra1		= &zero,
1199 		.extra2		= &one,
1200 	},
1201 #endif
1202 #ifdef CONFIG_BPF_SYSCALL
1203 	{
1204 		.procname	= "unprivileged_bpf_disabled",
1205 		.data		= &sysctl_unprivileged_bpf_disabled,
1206 		.maxlen		= sizeof(sysctl_unprivileged_bpf_disabled),
1207 		.mode		= 0644,
1208 		/* only handle a transition from default "0" to "1" */
1209 		.proc_handler	= proc_dointvec_minmax,
1210 		.extra1		= &one,
1211 		.extra2		= &one,
1212 	},
1213 #endif
1214 #if defined(CONFIG_TREE_RCU) || defined(CONFIG_PREEMPT_RCU)
1215 	{
1216 		.procname	= "panic_on_rcu_stall",
1217 		.data		= &sysctl_panic_on_rcu_stall,
1218 		.maxlen		= sizeof(sysctl_panic_on_rcu_stall),
1219 		.mode		= 0644,
1220 		.proc_handler	= proc_dointvec_minmax,
1221 		.extra1		= &zero,
1222 		.extra2		= &one,
1223 	},
1224 #endif
1225 	{ }
1226 };
1227 
1228 static struct ctl_table vm_table[] = {
1229 	{
1230 		.procname	= "overcommit_memory",
1231 		.data		= &sysctl_overcommit_memory,
1232 		.maxlen		= sizeof(sysctl_overcommit_memory),
1233 		.mode		= 0644,
1234 		.proc_handler	= proc_dointvec_minmax,
1235 		.extra1		= &zero,
1236 		.extra2		= &two,
1237 	},
1238 	{
1239 		.procname	= "panic_on_oom",
1240 		.data		= &sysctl_panic_on_oom,
1241 		.maxlen		= sizeof(sysctl_panic_on_oom),
1242 		.mode		= 0644,
1243 		.proc_handler	= proc_dointvec_minmax,
1244 		.extra1		= &zero,
1245 		.extra2		= &two,
1246 	},
1247 	{
1248 		.procname	= "oom_kill_allocating_task",
1249 		.data		= &sysctl_oom_kill_allocating_task,
1250 		.maxlen		= sizeof(sysctl_oom_kill_allocating_task),
1251 		.mode		= 0644,
1252 		.proc_handler	= proc_dointvec,
1253 	},
1254 	{
1255 		.procname	= "oom_dump_tasks",
1256 		.data		= &sysctl_oom_dump_tasks,
1257 		.maxlen		= sizeof(sysctl_oom_dump_tasks),
1258 		.mode		= 0644,
1259 		.proc_handler	= proc_dointvec,
1260 	},
1261 	{
1262 		.procname	= "overcommit_ratio",
1263 		.data		= &sysctl_overcommit_ratio,
1264 		.maxlen		= sizeof(sysctl_overcommit_ratio),
1265 		.mode		= 0644,
1266 		.proc_handler	= overcommit_ratio_handler,
1267 	},
1268 	{
1269 		.procname	= "overcommit_kbytes",
1270 		.data		= &sysctl_overcommit_kbytes,
1271 		.maxlen		= sizeof(sysctl_overcommit_kbytes),
1272 		.mode		= 0644,
1273 		.proc_handler	= overcommit_kbytes_handler,
1274 	},
1275 	{
1276 		.procname	= "page-cluster",
1277 		.data		= &page_cluster,
1278 		.maxlen		= sizeof(int),
1279 		.mode		= 0644,
1280 		.proc_handler	= proc_dointvec_minmax,
1281 		.extra1		= &zero,
1282 	},
1283 	{
1284 		.procname	= "dirty_background_ratio",
1285 		.data		= &dirty_background_ratio,
1286 		.maxlen		= sizeof(dirty_background_ratio),
1287 		.mode		= 0644,
1288 		.proc_handler	= dirty_background_ratio_handler,
1289 		.extra1		= &zero,
1290 		.extra2		= &one_hundred,
1291 	},
1292 	{
1293 		.procname	= "dirty_background_bytes",
1294 		.data		= &dirty_background_bytes,
1295 		.maxlen		= sizeof(dirty_background_bytes),
1296 		.mode		= 0644,
1297 		.proc_handler	= dirty_background_bytes_handler,
1298 		.extra1		= &one_ul,
1299 	},
1300 	{
1301 		.procname	= "dirty_ratio",
1302 		.data		= &vm_dirty_ratio,
1303 		.maxlen		= sizeof(vm_dirty_ratio),
1304 		.mode		= 0644,
1305 		.proc_handler	= dirty_ratio_handler,
1306 		.extra1		= &zero,
1307 		.extra2		= &one_hundred,
1308 	},
1309 	{
1310 		.procname	= "dirty_bytes",
1311 		.data		= &vm_dirty_bytes,
1312 		.maxlen		= sizeof(vm_dirty_bytes),
1313 		.mode		= 0644,
1314 		.proc_handler	= dirty_bytes_handler,
1315 		.extra1		= &dirty_bytes_min,
1316 	},
1317 	{
1318 		.procname	= "dirty_writeback_centisecs",
1319 		.data		= &dirty_writeback_interval,
1320 		.maxlen		= sizeof(dirty_writeback_interval),
1321 		.mode		= 0644,
1322 		.proc_handler	= dirty_writeback_centisecs_handler,
1323 	},
1324 	{
1325 		.procname	= "dirty_expire_centisecs",
1326 		.data		= &dirty_expire_interval,
1327 		.maxlen		= sizeof(dirty_expire_interval),
1328 		.mode		= 0644,
1329 		.proc_handler	= proc_dointvec_minmax,
1330 		.extra1		= &zero,
1331 	},
1332 	{
1333 		.procname	= "dirtytime_expire_seconds",
1334 		.data		= &dirtytime_expire_interval,
1335 		.maxlen		= sizeof(dirtytime_expire_interval),
1336 		.mode		= 0644,
1337 		.proc_handler	= dirtytime_interval_handler,
1338 		.extra1		= &zero,
1339 	},
1340 	{
1341 		.procname	= "swappiness",
1342 		.data		= &vm_swappiness,
1343 		.maxlen		= sizeof(vm_swappiness),
1344 		.mode		= 0644,
1345 		.proc_handler	= proc_dointvec_minmax,
1346 		.extra1		= &zero,
1347 		.extra2		= &one_hundred,
1348 	},
1349 #ifdef CONFIG_HUGETLB_PAGE
1350 	{
1351 		.procname	= "nr_hugepages",
1352 		.data		= NULL,
1353 		.maxlen		= sizeof(unsigned long),
1354 		.mode		= 0644,
1355 		.proc_handler	= hugetlb_sysctl_handler,
1356 	},
1357 #ifdef CONFIG_NUMA
1358 	{
1359 		.procname       = "nr_hugepages_mempolicy",
1360 		.data           = NULL,
1361 		.maxlen         = sizeof(unsigned long),
1362 		.mode           = 0644,
1363 		.proc_handler   = &hugetlb_mempolicy_sysctl_handler,
1364 	},
1365 	{
1366 		.procname		= "numa_stat",
1367 		.data			= &sysctl_vm_numa_stat,
1368 		.maxlen			= sizeof(int),
1369 		.mode			= 0644,
1370 		.proc_handler	= sysctl_vm_numa_stat_handler,
1371 		.extra1			= &zero,
1372 		.extra2			= &one,
1373 	},
1374 #endif
1375 	 {
1376 		.procname	= "hugetlb_shm_group",
1377 		.data		= &sysctl_hugetlb_shm_group,
1378 		.maxlen		= sizeof(gid_t),
1379 		.mode		= 0644,
1380 		.proc_handler	= proc_dointvec,
1381 	 },
1382 	{
1383 		.procname	= "nr_overcommit_hugepages",
1384 		.data		= NULL,
1385 		.maxlen		= sizeof(unsigned long),
1386 		.mode		= 0644,
1387 		.proc_handler	= hugetlb_overcommit_handler,
1388 	},
1389 #endif
1390 	{
1391 		.procname	= "lowmem_reserve_ratio",
1392 		.data		= &sysctl_lowmem_reserve_ratio,
1393 		.maxlen		= sizeof(sysctl_lowmem_reserve_ratio),
1394 		.mode		= 0644,
1395 		.proc_handler	= lowmem_reserve_ratio_sysctl_handler,
1396 	},
1397 	{
1398 		.procname	= "drop_caches",
1399 		.data		= &sysctl_drop_caches,
1400 		.maxlen		= sizeof(int),
1401 		.mode		= 0644,
1402 		.proc_handler	= drop_caches_sysctl_handler,
1403 		.extra1		= &one,
1404 		.extra2		= &four,
1405 	},
1406 #ifdef CONFIG_COMPACTION
1407 	{
1408 		.procname	= "compact_memory",
1409 		.data		= &sysctl_compact_memory,
1410 		.maxlen		= sizeof(int),
1411 		.mode		= 0200,
1412 		.proc_handler	= sysctl_compaction_handler,
1413 	},
1414 	{
1415 		.procname	= "extfrag_threshold",
1416 		.data		= &sysctl_extfrag_threshold,
1417 		.maxlen		= sizeof(int),
1418 		.mode		= 0644,
1419 		.proc_handler	= sysctl_extfrag_handler,
1420 		.extra1		= &min_extfrag_threshold,
1421 		.extra2		= &max_extfrag_threshold,
1422 	},
1423 	{
1424 		.procname	= "compact_unevictable_allowed",
1425 		.data		= &sysctl_compact_unevictable_allowed,
1426 		.maxlen		= sizeof(int),
1427 		.mode		= 0644,
1428 		.proc_handler	= proc_dointvec,
1429 		.extra1		= &zero,
1430 		.extra2		= &one,
1431 	},
1432 
1433 #endif /* CONFIG_COMPACTION */
1434 	{
1435 		.procname	= "min_free_kbytes",
1436 		.data		= &min_free_kbytes,
1437 		.maxlen		= sizeof(min_free_kbytes),
1438 		.mode		= 0644,
1439 		.proc_handler	= min_free_kbytes_sysctl_handler,
1440 		.extra1		= &zero,
1441 	},
1442 	{
1443 		.procname	= "watermark_scale_factor",
1444 		.data		= &watermark_scale_factor,
1445 		.maxlen		= sizeof(watermark_scale_factor),
1446 		.mode		= 0644,
1447 		.proc_handler	= watermark_scale_factor_sysctl_handler,
1448 		.extra1		= &one,
1449 		.extra2		= &one_thousand,
1450 	},
1451 	{
1452 		.procname	= "percpu_pagelist_fraction",
1453 		.data		= &percpu_pagelist_fraction,
1454 		.maxlen		= sizeof(percpu_pagelist_fraction),
1455 		.mode		= 0644,
1456 		.proc_handler	= percpu_pagelist_fraction_sysctl_handler,
1457 		.extra1		= &zero,
1458 	},
1459 #ifdef CONFIG_MMU
1460 	{
1461 		.procname	= "max_map_count",
1462 		.data		= &sysctl_max_map_count,
1463 		.maxlen		= sizeof(sysctl_max_map_count),
1464 		.mode		= 0644,
1465 		.proc_handler	= proc_dointvec_minmax,
1466 		.extra1		= &zero,
1467 	},
1468 #else
1469 	{
1470 		.procname	= "nr_trim_pages",
1471 		.data		= &sysctl_nr_trim_pages,
1472 		.maxlen		= sizeof(sysctl_nr_trim_pages),
1473 		.mode		= 0644,
1474 		.proc_handler	= proc_dointvec_minmax,
1475 		.extra1		= &zero,
1476 	},
1477 #endif
1478 	{
1479 		.procname	= "laptop_mode",
1480 		.data		= &laptop_mode,
1481 		.maxlen		= sizeof(laptop_mode),
1482 		.mode		= 0644,
1483 		.proc_handler	= proc_dointvec_jiffies,
1484 	},
1485 	{
1486 		.procname	= "block_dump",
1487 		.data		= &block_dump,
1488 		.maxlen		= sizeof(block_dump),
1489 		.mode		= 0644,
1490 		.proc_handler	= proc_dointvec,
1491 		.extra1		= &zero,
1492 	},
1493 	{
1494 		.procname	= "vfs_cache_pressure",
1495 		.data		= &sysctl_vfs_cache_pressure,
1496 		.maxlen		= sizeof(sysctl_vfs_cache_pressure),
1497 		.mode		= 0644,
1498 		.proc_handler	= proc_dointvec,
1499 		.extra1		= &zero,
1500 	},
1501 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1502 	{
1503 		.procname	= "legacy_va_layout",
1504 		.data		= &sysctl_legacy_va_layout,
1505 		.maxlen		= sizeof(sysctl_legacy_va_layout),
1506 		.mode		= 0644,
1507 		.proc_handler	= proc_dointvec,
1508 		.extra1		= &zero,
1509 	},
1510 #endif
1511 #ifdef CONFIG_NUMA
1512 	{
1513 		.procname	= "zone_reclaim_mode",
1514 		.data		= &node_reclaim_mode,
1515 		.maxlen		= sizeof(node_reclaim_mode),
1516 		.mode		= 0644,
1517 		.proc_handler	= proc_dointvec,
1518 		.extra1		= &zero,
1519 	},
1520 	{
1521 		.procname	= "min_unmapped_ratio",
1522 		.data		= &sysctl_min_unmapped_ratio,
1523 		.maxlen		= sizeof(sysctl_min_unmapped_ratio),
1524 		.mode		= 0644,
1525 		.proc_handler	= sysctl_min_unmapped_ratio_sysctl_handler,
1526 		.extra1		= &zero,
1527 		.extra2		= &one_hundred,
1528 	},
1529 	{
1530 		.procname	= "min_slab_ratio",
1531 		.data		= &sysctl_min_slab_ratio,
1532 		.maxlen		= sizeof(sysctl_min_slab_ratio),
1533 		.mode		= 0644,
1534 		.proc_handler	= sysctl_min_slab_ratio_sysctl_handler,
1535 		.extra1		= &zero,
1536 		.extra2		= &one_hundred,
1537 	},
1538 #endif
1539 #ifdef CONFIG_SMP
1540 	{
1541 		.procname	= "stat_interval",
1542 		.data		= &sysctl_stat_interval,
1543 		.maxlen		= sizeof(sysctl_stat_interval),
1544 		.mode		= 0644,
1545 		.proc_handler	= proc_dointvec_jiffies,
1546 	},
1547 	{
1548 		.procname	= "stat_refresh",
1549 		.data		= NULL,
1550 		.maxlen		= 0,
1551 		.mode		= 0600,
1552 		.proc_handler	= vmstat_refresh,
1553 	},
1554 #endif
1555 #ifdef CONFIG_MMU
1556 	{
1557 		.procname	= "mmap_min_addr",
1558 		.data		= &dac_mmap_min_addr,
1559 		.maxlen		= sizeof(unsigned long),
1560 		.mode		= 0644,
1561 		.proc_handler	= mmap_min_addr_handler,
1562 	},
1563 #endif
1564 #ifdef CONFIG_NUMA
1565 	{
1566 		.procname	= "numa_zonelist_order",
1567 		.data		= &numa_zonelist_order,
1568 		.maxlen		= NUMA_ZONELIST_ORDER_LEN,
1569 		.mode		= 0644,
1570 		.proc_handler	= numa_zonelist_order_handler,
1571 	},
1572 #endif
1573 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1574    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1575 	{
1576 		.procname	= "vdso_enabled",
1577 #ifdef CONFIG_X86_32
1578 		.data		= &vdso32_enabled,
1579 		.maxlen		= sizeof(vdso32_enabled),
1580 #else
1581 		.data		= &vdso_enabled,
1582 		.maxlen		= sizeof(vdso_enabled),
1583 #endif
1584 		.mode		= 0644,
1585 		.proc_handler	= proc_dointvec,
1586 		.extra1		= &zero,
1587 	},
1588 #endif
1589 #ifdef CONFIG_HIGHMEM
1590 	{
1591 		.procname	= "highmem_is_dirtyable",
1592 		.data		= &vm_highmem_is_dirtyable,
1593 		.maxlen		= sizeof(vm_highmem_is_dirtyable),
1594 		.mode		= 0644,
1595 		.proc_handler	= proc_dointvec_minmax,
1596 		.extra1		= &zero,
1597 		.extra2		= &one,
1598 	},
1599 #endif
1600 #ifdef CONFIG_MEMORY_FAILURE
1601 	{
1602 		.procname	= "memory_failure_early_kill",
1603 		.data		= &sysctl_memory_failure_early_kill,
1604 		.maxlen		= sizeof(sysctl_memory_failure_early_kill),
1605 		.mode		= 0644,
1606 		.proc_handler	= proc_dointvec_minmax,
1607 		.extra1		= &zero,
1608 		.extra2		= &one,
1609 	},
1610 	{
1611 		.procname	= "memory_failure_recovery",
1612 		.data		= &sysctl_memory_failure_recovery,
1613 		.maxlen		= sizeof(sysctl_memory_failure_recovery),
1614 		.mode		= 0644,
1615 		.proc_handler	= proc_dointvec_minmax,
1616 		.extra1		= &zero,
1617 		.extra2		= &one,
1618 	},
1619 #endif
1620 	{
1621 		.procname	= "user_reserve_kbytes",
1622 		.data		= &sysctl_user_reserve_kbytes,
1623 		.maxlen		= sizeof(sysctl_user_reserve_kbytes),
1624 		.mode		= 0644,
1625 		.proc_handler	= proc_doulongvec_minmax,
1626 	},
1627 	{
1628 		.procname	= "admin_reserve_kbytes",
1629 		.data		= &sysctl_admin_reserve_kbytes,
1630 		.maxlen		= sizeof(sysctl_admin_reserve_kbytes),
1631 		.mode		= 0644,
1632 		.proc_handler	= proc_doulongvec_minmax,
1633 	},
1634 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
1635 	{
1636 		.procname	= "mmap_rnd_bits",
1637 		.data		= &mmap_rnd_bits,
1638 		.maxlen		= sizeof(mmap_rnd_bits),
1639 		.mode		= 0600,
1640 		.proc_handler	= proc_dointvec_minmax,
1641 		.extra1		= (void *)&mmap_rnd_bits_min,
1642 		.extra2		= (void *)&mmap_rnd_bits_max,
1643 	},
1644 #endif
1645 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
1646 	{
1647 		.procname	= "mmap_rnd_compat_bits",
1648 		.data		= &mmap_rnd_compat_bits,
1649 		.maxlen		= sizeof(mmap_rnd_compat_bits),
1650 		.mode		= 0600,
1651 		.proc_handler	= proc_dointvec_minmax,
1652 		.extra1		= (void *)&mmap_rnd_compat_bits_min,
1653 		.extra2		= (void *)&mmap_rnd_compat_bits_max,
1654 	},
1655 #endif
1656 	{ }
1657 };
1658 
1659 static struct ctl_table fs_table[] = {
1660 	{
1661 		.procname	= "inode-nr",
1662 		.data		= &inodes_stat,
1663 		.maxlen		= 2*sizeof(long),
1664 		.mode		= 0444,
1665 		.proc_handler	= proc_nr_inodes,
1666 	},
1667 	{
1668 		.procname	= "inode-state",
1669 		.data		= &inodes_stat,
1670 		.maxlen		= 7*sizeof(long),
1671 		.mode		= 0444,
1672 		.proc_handler	= proc_nr_inodes,
1673 	},
1674 	{
1675 		.procname	= "file-nr",
1676 		.data		= &files_stat,
1677 		.maxlen		= sizeof(files_stat),
1678 		.mode		= 0444,
1679 		.proc_handler	= proc_nr_files,
1680 	},
1681 	{
1682 		.procname	= "file-max",
1683 		.data		= &files_stat.max_files,
1684 		.maxlen		= sizeof(files_stat.max_files),
1685 		.mode		= 0644,
1686 		.proc_handler	= proc_doulongvec_minmax,
1687 	},
1688 	{
1689 		.procname	= "nr_open",
1690 		.data		= &sysctl_nr_open,
1691 		.maxlen		= sizeof(unsigned int),
1692 		.mode		= 0644,
1693 		.proc_handler	= proc_dointvec_minmax,
1694 		.extra1		= &sysctl_nr_open_min,
1695 		.extra2		= &sysctl_nr_open_max,
1696 	},
1697 	{
1698 		.procname	= "dentry-state",
1699 		.data		= &dentry_stat,
1700 		.maxlen		= 6*sizeof(long),
1701 		.mode		= 0444,
1702 		.proc_handler	= proc_nr_dentry,
1703 	},
1704 	{
1705 		.procname	= "overflowuid",
1706 		.data		= &fs_overflowuid,
1707 		.maxlen		= sizeof(int),
1708 		.mode		= 0644,
1709 		.proc_handler	= proc_dointvec_minmax,
1710 		.extra1		= &minolduid,
1711 		.extra2		= &maxolduid,
1712 	},
1713 	{
1714 		.procname	= "overflowgid",
1715 		.data		= &fs_overflowgid,
1716 		.maxlen		= sizeof(int),
1717 		.mode		= 0644,
1718 		.proc_handler	= proc_dointvec_minmax,
1719 		.extra1		= &minolduid,
1720 		.extra2		= &maxolduid,
1721 	},
1722 #ifdef CONFIG_FILE_LOCKING
1723 	{
1724 		.procname	= "leases-enable",
1725 		.data		= &leases_enable,
1726 		.maxlen		= sizeof(int),
1727 		.mode		= 0644,
1728 		.proc_handler	= proc_dointvec,
1729 	},
1730 #endif
1731 #ifdef CONFIG_DNOTIFY
1732 	{
1733 		.procname	= "dir-notify-enable",
1734 		.data		= &dir_notify_enable,
1735 		.maxlen		= sizeof(int),
1736 		.mode		= 0644,
1737 		.proc_handler	= proc_dointvec,
1738 	},
1739 #endif
1740 #ifdef CONFIG_MMU
1741 #ifdef CONFIG_FILE_LOCKING
1742 	{
1743 		.procname	= "lease-break-time",
1744 		.data		= &lease_break_time,
1745 		.maxlen		= sizeof(int),
1746 		.mode		= 0644,
1747 		.proc_handler	= proc_dointvec,
1748 	},
1749 #endif
1750 #ifdef CONFIG_AIO
1751 	{
1752 		.procname	= "aio-nr",
1753 		.data		= &aio_nr,
1754 		.maxlen		= sizeof(aio_nr),
1755 		.mode		= 0444,
1756 		.proc_handler	= proc_doulongvec_minmax,
1757 	},
1758 	{
1759 		.procname	= "aio-max-nr",
1760 		.data		= &aio_max_nr,
1761 		.maxlen		= sizeof(aio_max_nr),
1762 		.mode		= 0644,
1763 		.proc_handler	= proc_doulongvec_minmax,
1764 	},
1765 #endif /* CONFIG_AIO */
1766 #ifdef CONFIG_INOTIFY_USER
1767 	{
1768 		.procname	= "inotify",
1769 		.mode		= 0555,
1770 		.child		= inotify_table,
1771 	},
1772 #endif
1773 #ifdef CONFIG_EPOLL
1774 	{
1775 		.procname	= "epoll",
1776 		.mode		= 0555,
1777 		.child		= epoll_table,
1778 	},
1779 #endif
1780 #endif
1781 	{
1782 		.procname	= "protected_symlinks",
1783 		.data		= &sysctl_protected_symlinks,
1784 		.maxlen		= sizeof(int),
1785 		.mode		= 0600,
1786 		.proc_handler	= proc_dointvec_minmax,
1787 		.extra1		= &zero,
1788 		.extra2		= &one,
1789 	},
1790 	{
1791 		.procname	= "protected_hardlinks",
1792 		.data		= &sysctl_protected_hardlinks,
1793 		.maxlen		= sizeof(int),
1794 		.mode		= 0600,
1795 		.proc_handler	= proc_dointvec_minmax,
1796 		.extra1		= &zero,
1797 		.extra2		= &one,
1798 	},
1799 	{
1800 		.procname	= "suid_dumpable",
1801 		.data		= &suid_dumpable,
1802 		.maxlen		= sizeof(int),
1803 		.mode		= 0644,
1804 		.proc_handler	= proc_dointvec_minmax_coredump,
1805 		.extra1		= &zero,
1806 		.extra2		= &two,
1807 	},
1808 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1809 	{
1810 		.procname	= "binfmt_misc",
1811 		.mode		= 0555,
1812 		.child		= sysctl_mount_point,
1813 	},
1814 #endif
1815 	{
1816 		.procname	= "pipe-max-size",
1817 		.data		= &pipe_max_size,
1818 		.maxlen		= sizeof(pipe_max_size),
1819 		.mode		= 0644,
1820 		.proc_handler	= proc_dopipe_max_size,
1821 	},
1822 	{
1823 		.procname	= "pipe-user-pages-hard",
1824 		.data		= &pipe_user_pages_hard,
1825 		.maxlen		= sizeof(pipe_user_pages_hard),
1826 		.mode		= 0644,
1827 		.proc_handler	= proc_doulongvec_minmax,
1828 	},
1829 	{
1830 		.procname	= "pipe-user-pages-soft",
1831 		.data		= &pipe_user_pages_soft,
1832 		.maxlen		= sizeof(pipe_user_pages_soft),
1833 		.mode		= 0644,
1834 		.proc_handler	= proc_doulongvec_minmax,
1835 	},
1836 	{
1837 		.procname	= "mount-max",
1838 		.data		= &sysctl_mount_max,
1839 		.maxlen		= sizeof(unsigned int),
1840 		.mode		= 0644,
1841 		.proc_handler	= proc_dointvec_minmax,
1842 		.extra1		= &one,
1843 	},
1844 	{ }
1845 };
1846 
1847 static struct ctl_table debug_table[] = {
1848 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1849 	{
1850 		.procname	= "exception-trace",
1851 		.data		= &show_unhandled_signals,
1852 		.maxlen		= sizeof(int),
1853 		.mode		= 0644,
1854 		.proc_handler	= proc_dointvec
1855 	},
1856 #endif
1857 #if defined(CONFIG_OPTPROBES)
1858 	{
1859 		.procname	= "kprobes-optimization",
1860 		.data		= &sysctl_kprobes_optimization,
1861 		.maxlen		= sizeof(int),
1862 		.mode		= 0644,
1863 		.proc_handler	= proc_kprobes_optimization_handler,
1864 		.extra1		= &zero,
1865 		.extra2		= &one,
1866 	},
1867 #endif
1868 	{ }
1869 };
1870 
1871 static struct ctl_table dev_table[] = {
1872 	{ }
1873 };
1874 
1875 int __init sysctl_init(void)
1876 {
1877 	struct ctl_table_header *hdr;
1878 
1879 	hdr = register_sysctl_table(sysctl_base_table);
1880 	kmemleak_not_leak(hdr);
1881 	return 0;
1882 }
1883 
1884 #endif /* CONFIG_SYSCTL */
1885 
1886 /*
1887  * /proc/sys support
1888  */
1889 
1890 #ifdef CONFIG_PROC_SYSCTL
1891 
1892 static int _proc_do_string(char *data, int maxlen, int write,
1893 			   char __user *buffer,
1894 			   size_t *lenp, loff_t *ppos)
1895 {
1896 	size_t len;
1897 	char __user *p;
1898 	char c;
1899 
1900 	if (!data || !maxlen || !*lenp) {
1901 		*lenp = 0;
1902 		return 0;
1903 	}
1904 
1905 	if (write) {
1906 		if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
1907 			/* Only continue writes not past the end of buffer. */
1908 			len = strlen(data);
1909 			if (len > maxlen - 1)
1910 				len = maxlen - 1;
1911 
1912 			if (*ppos > len)
1913 				return 0;
1914 			len = *ppos;
1915 		} else {
1916 			/* Start writing from beginning of buffer. */
1917 			len = 0;
1918 		}
1919 
1920 		*ppos += *lenp;
1921 		p = buffer;
1922 		while ((p - buffer) < *lenp && len < maxlen - 1) {
1923 			if (get_user(c, p++))
1924 				return -EFAULT;
1925 			if (c == 0 || c == '\n')
1926 				break;
1927 			data[len++] = c;
1928 		}
1929 		data[len] = 0;
1930 	} else {
1931 		len = strlen(data);
1932 		if (len > maxlen)
1933 			len = maxlen;
1934 
1935 		if (*ppos > len) {
1936 			*lenp = 0;
1937 			return 0;
1938 		}
1939 
1940 		data += *ppos;
1941 		len  -= *ppos;
1942 
1943 		if (len > *lenp)
1944 			len = *lenp;
1945 		if (len)
1946 			if (copy_to_user(buffer, data, len))
1947 				return -EFAULT;
1948 		if (len < *lenp) {
1949 			if (put_user('\n', buffer + len))
1950 				return -EFAULT;
1951 			len++;
1952 		}
1953 		*lenp = len;
1954 		*ppos += len;
1955 	}
1956 	return 0;
1957 }
1958 
1959 static void warn_sysctl_write(struct ctl_table *table)
1960 {
1961 	pr_warn_once("%s wrote to %s when file position was not 0!\n"
1962 		"This will not be supported in the future. To silence this\n"
1963 		"warning, set kernel.sysctl_writes_strict = -1\n",
1964 		current->comm, table->procname);
1965 }
1966 
1967 /**
1968  * proc_first_pos_non_zero_ignore - check if firs position is allowed
1969  * @ppos: file position
1970  * @table: the sysctl table
1971  *
1972  * Returns true if the first position is non-zero and the sysctl_writes_strict
1973  * mode indicates this is not allowed for numeric input types. String proc
1974  * hadlers can ignore the return value.
1975  */
1976 static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
1977 					   struct ctl_table *table)
1978 {
1979 	if (!*ppos)
1980 		return false;
1981 
1982 	switch (sysctl_writes_strict) {
1983 	case SYSCTL_WRITES_STRICT:
1984 		return true;
1985 	case SYSCTL_WRITES_WARN:
1986 		warn_sysctl_write(table);
1987 		return false;
1988 	default:
1989 		return false;
1990 	}
1991 }
1992 
1993 /**
1994  * proc_dostring - read a string sysctl
1995  * @table: the sysctl table
1996  * @write: %TRUE if this is a write to the sysctl file
1997  * @buffer: the user buffer
1998  * @lenp: the size of the user buffer
1999  * @ppos: file position
2000  *
2001  * Reads/writes a string from/to the user buffer. If the kernel
2002  * buffer provided is not large enough to hold the string, the
2003  * string is truncated. The copied string is %NULL-terminated.
2004  * If the string is being read by the user process, it is copied
2005  * and a newline '\n' is added. It is truncated if the buffer is
2006  * not large enough.
2007  *
2008  * Returns 0 on success.
2009  */
2010 int proc_dostring(struct ctl_table *table, int write,
2011 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2012 {
2013 	if (write)
2014 		proc_first_pos_non_zero_ignore(ppos, table);
2015 
2016 	return _proc_do_string((char *)(table->data), table->maxlen, write,
2017 			       (char __user *)buffer, lenp, ppos);
2018 }
2019 
2020 static size_t proc_skip_spaces(char **buf)
2021 {
2022 	size_t ret;
2023 	char *tmp = skip_spaces(*buf);
2024 	ret = tmp - *buf;
2025 	*buf = tmp;
2026 	return ret;
2027 }
2028 
2029 static void proc_skip_char(char **buf, size_t *size, const char v)
2030 {
2031 	while (*size) {
2032 		if (**buf != v)
2033 			break;
2034 		(*size)--;
2035 		(*buf)++;
2036 	}
2037 }
2038 
2039 #define TMPBUFLEN 22
2040 /**
2041  * proc_get_long - reads an ASCII formatted integer from a user buffer
2042  *
2043  * @buf: a kernel buffer
2044  * @size: size of the kernel buffer
2045  * @val: this is where the number will be stored
2046  * @neg: set to %TRUE if number is negative
2047  * @perm_tr: a vector which contains the allowed trailers
2048  * @perm_tr_len: size of the perm_tr vector
2049  * @tr: pointer to store the trailer character
2050  *
2051  * In case of success %0 is returned and @buf and @size are updated with
2052  * the amount of bytes read. If @tr is non-NULL and a trailing
2053  * character exists (size is non-zero after returning from this
2054  * function), @tr is updated with the trailing character.
2055  */
2056 static int proc_get_long(char **buf, size_t *size,
2057 			  unsigned long *val, bool *neg,
2058 			  const char *perm_tr, unsigned perm_tr_len, char *tr)
2059 {
2060 	int len;
2061 	char *p, tmp[TMPBUFLEN];
2062 
2063 	if (!*size)
2064 		return -EINVAL;
2065 
2066 	len = *size;
2067 	if (len > TMPBUFLEN - 1)
2068 		len = TMPBUFLEN - 1;
2069 
2070 	memcpy(tmp, *buf, len);
2071 
2072 	tmp[len] = 0;
2073 	p = tmp;
2074 	if (*p == '-' && *size > 1) {
2075 		*neg = true;
2076 		p++;
2077 	} else
2078 		*neg = false;
2079 	if (!isdigit(*p))
2080 		return -EINVAL;
2081 
2082 	*val = simple_strtoul(p, &p, 0);
2083 
2084 	len = p - tmp;
2085 
2086 	/* We don't know if the next char is whitespace thus we may accept
2087 	 * invalid integers (e.g. 1234...a) or two integers instead of one
2088 	 * (e.g. 123...1). So lets not allow such large numbers. */
2089 	if (len == TMPBUFLEN - 1)
2090 		return -EINVAL;
2091 
2092 	if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2093 		return -EINVAL;
2094 
2095 	if (tr && (len < *size))
2096 		*tr = *p;
2097 
2098 	*buf += len;
2099 	*size -= len;
2100 
2101 	return 0;
2102 }
2103 
2104 /**
2105  * proc_put_long - converts an integer to a decimal ASCII formatted string
2106  *
2107  * @buf: the user buffer
2108  * @size: the size of the user buffer
2109  * @val: the integer to be converted
2110  * @neg: sign of the number, %TRUE for negative
2111  *
2112  * In case of success %0 is returned and @buf and @size are updated with
2113  * the amount of bytes written.
2114  */
2115 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2116 			  bool neg)
2117 {
2118 	int len;
2119 	char tmp[TMPBUFLEN], *p = tmp;
2120 
2121 	sprintf(p, "%s%lu", neg ? "-" : "", val);
2122 	len = strlen(tmp);
2123 	if (len > *size)
2124 		len = *size;
2125 	if (copy_to_user(*buf, tmp, len))
2126 		return -EFAULT;
2127 	*size -= len;
2128 	*buf += len;
2129 	return 0;
2130 }
2131 #undef TMPBUFLEN
2132 
2133 static int proc_put_char(void __user **buf, size_t *size, char c)
2134 {
2135 	if (*size) {
2136 		char __user **buffer = (char __user **)buf;
2137 		if (put_user(c, *buffer))
2138 			return -EFAULT;
2139 		(*size)--, (*buffer)++;
2140 		*buf = *buffer;
2141 	}
2142 	return 0;
2143 }
2144 
2145 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2146 				 int *valp,
2147 				 int write, void *data)
2148 {
2149 	if (write) {
2150 		if (*negp) {
2151 			if (*lvalp > (unsigned long) INT_MAX + 1)
2152 				return -EINVAL;
2153 			*valp = -*lvalp;
2154 		} else {
2155 			if (*lvalp > (unsigned long) INT_MAX)
2156 				return -EINVAL;
2157 			*valp = *lvalp;
2158 		}
2159 	} else {
2160 		int val = *valp;
2161 		if (val < 0) {
2162 			*negp = true;
2163 			*lvalp = -(unsigned long)val;
2164 		} else {
2165 			*negp = false;
2166 			*lvalp = (unsigned long)val;
2167 		}
2168 	}
2169 	return 0;
2170 }
2171 
2172 static int do_proc_douintvec_conv(unsigned long *lvalp,
2173 				  unsigned int *valp,
2174 				  int write, void *data)
2175 {
2176 	if (write) {
2177 		if (*lvalp > UINT_MAX)
2178 			return -EINVAL;
2179 		*valp = *lvalp;
2180 	} else {
2181 		unsigned int val = *valp;
2182 		*lvalp = (unsigned long)val;
2183 	}
2184 	return 0;
2185 }
2186 
2187 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2188 
2189 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2190 		  int write, void __user *buffer,
2191 		  size_t *lenp, loff_t *ppos,
2192 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2193 			      int write, void *data),
2194 		  void *data)
2195 {
2196 	int *i, vleft, first = 1, err = 0;
2197 	size_t left;
2198 	char *kbuf = NULL, *p;
2199 
2200 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2201 		*lenp = 0;
2202 		return 0;
2203 	}
2204 
2205 	i = (int *) tbl_data;
2206 	vleft = table->maxlen / sizeof(*i);
2207 	left = *lenp;
2208 
2209 	if (!conv)
2210 		conv = do_proc_dointvec_conv;
2211 
2212 	if (write) {
2213 		if (proc_first_pos_non_zero_ignore(ppos, table))
2214 			goto out;
2215 
2216 		if (left > PAGE_SIZE - 1)
2217 			left = PAGE_SIZE - 1;
2218 		p = kbuf = memdup_user_nul(buffer, left);
2219 		if (IS_ERR(kbuf))
2220 			return PTR_ERR(kbuf);
2221 	}
2222 
2223 	for (; left && vleft--; i++, first=0) {
2224 		unsigned long lval;
2225 		bool neg;
2226 
2227 		if (write) {
2228 			left -= proc_skip_spaces(&p);
2229 
2230 			if (!left)
2231 				break;
2232 			err = proc_get_long(&p, &left, &lval, &neg,
2233 					     proc_wspace_sep,
2234 					     sizeof(proc_wspace_sep), NULL);
2235 			if (err)
2236 				break;
2237 			if (conv(&neg, &lval, i, 1, data)) {
2238 				err = -EINVAL;
2239 				break;
2240 			}
2241 		} else {
2242 			if (conv(&neg, &lval, i, 0, data)) {
2243 				err = -EINVAL;
2244 				break;
2245 			}
2246 			if (!first)
2247 				err = proc_put_char(&buffer, &left, '\t');
2248 			if (err)
2249 				break;
2250 			err = proc_put_long(&buffer, &left, lval, neg);
2251 			if (err)
2252 				break;
2253 		}
2254 	}
2255 
2256 	if (!write && !first && left && !err)
2257 		err = proc_put_char(&buffer, &left, '\n');
2258 	if (write && !err && left)
2259 		left -= proc_skip_spaces(&p);
2260 	if (write) {
2261 		kfree(kbuf);
2262 		if (first)
2263 			return err ? : -EINVAL;
2264 	}
2265 	*lenp -= left;
2266 out:
2267 	*ppos += *lenp;
2268 	return err;
2269 }
2270 
2271 static int do_proc_dointvec(struct ctl_table *table, int write,
2272 		  void __user *buffer, size_t *lenp, loff_t *ppos,
2273 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2274 			      int write, void *data),
2275 		  void *data)
2276 {
2277 	return __do_proc_dointvec(table->data, table, write,
2278 			buffer, lenp, ppos, conv, data);
2279 }
2280 
2281 static int do_proc_douintvec_w(unsigned int *tbl_data,
2282 			       struct ctl_table *table,
2283 			       void __user *buffer,
2284 			       size_t *lenp, loff_t *ppos,
2285 			       int (*conv)(unsigned long *lvalp,
2286 					   unsigned int *valp,
2287 					   int write, void *data),
2288 			       void *data)
2289 {
2290 	unsigned long lval;
2291 	int err = 0;
2292 	size_t left;
2293 	bool neg;
2294 	char *kbuf = NULL, *p;
2295 
2296 	left = *lenp;
2297 
2298 	if (proc_first_pos_non_zero_ignore(ppos, table))
2299 		goto bail_early;
2300 
2301 	if (left > PAGE_SIZE - 1)
2302 		left = PAGE_SIZE - 1;
2303 
2304 	p = kbuf = memdup_user_nul(buffer, left);
2305 	if (IS_ERR(kbuf))
2306 		return -EINVAL;
2307 
2308 	left -= proc_skip_spaces(&p);
2309 	if (!left) {
2310 		err = -EINVAL;
2311 		goto out_free;
2312 	}
2313 
2314 	err = proc_get_long(&p, &left, &lval, &neg,
2315 			     proc_wspace_sep,
2316 			     sizeof(proc_wspace_sep), NULL);
2317 	if (err || neg) {
2318 		err = -EINVAL;
2319 		goto out_free;
2320 	}
2321 
2322 	if (conv(&lval, tbl_data, 1, data)) {
2323 		err = -EINVAL;
2324 		goto out_free;
2325 	}
2326 
2327 	if (!err && left)
2328 		left -= proc_skip_spaces(&p);
2329 
2330 out_free:
2331 	kfree(kbuf);
2332 	if (err)
2333 		return -EINVAL;
2334 
2335 	return 0;
2336 
2337 	/* This is in keeping with old __do_proc_dointvec() */
2338 bail_early:
2339 	*ppos += *lenp;
2340 	return err;
2341 }
2342 
2343 static int do_proc_douintvec_r(unsigned int *tbl_data, void __user *buffer,
2344 			       size_t *lenp, loff_t *ppos,
2345 			       int (*conv)(unsigned long *lvalp,
2346 					   unsigned int *valp,
2347 					   int write, void *data),
2348 			       void *data)
2349 {
2350 	unsigned long lval;
2351 	int err = 0;
2352 	size_t left;
2353 
2354 	left = *lenp;
2355 
2356 	if (conv(&lval, tbl_data, 0, data)) {
2357 		err = -EINVAL;
2358 		goto out;
2359 	}
2360 
2361 	err = proc_put_long(&buffer, &left, lval, false);
2362 	if (err || !left)
2363 		goto out;
2364 
2365 	err = proc_put_char(&buffer, &left, '\n');
2366 
2367 out:
2368 	*lenp -= left;
2369 	*ppos += *lenp;
2370 
2371 	return err;
2372 }
2373 
2374 static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
2375 			       int write, void __user *buffer,
2376 			       size_t *lenp, loff_t *ppos,
2377 			       int (*conv)(unsigned long *lvalp,
2378 					   unsigned int *valp,
2379 					   int write, void *data),
2380 			       void *data)
2381 {
2382 	unsigned int *i, vleft;
2383 
2384 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2385 		*lenp = 0;
2386 		return 0;
2387 	}
2388 
2389 	i = (unsigned int *) tbl_data;
2390 	vleft = table->maxlen / sizeof(*i);
2391 
2392 	/*
2393 	 * Arrays are not supported, keep this simple. *Do not* add
2394 	 * support for them.
2395 	 */
2396 	if (vleft != 1) {
2397 		*lenp = 0;
2398 		return -EINVAL;
2399 	}
2400 
2401 	if (!conv)
2402 		conv = do_proc_douintvec_conv;
2403 
2404 	if (write)
2405 		return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
2406 					   conv, data);
2407 	return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
2408 }
2409 
2410 static int do_proc_douintvec(struct ctl_table *table, int write,
2411 			     void __user *buffer, size_t *lenp, loff_t *ppos,
2412 			     int (*conv)(unsigned long *lvalp,
2413 					 unsigned int *valp,
2414 					 int write, void *data),
2415 			     void *data)
2416 {
2417 	return __do_proc_douintvec(table->data, table, write,
2418 				   buffer, lenp, ppos, conv, data);
2419 }
2420 
2421 /**
2422  * proc_dointvec - read a vector of integers
2423  * @table: the sysctl table
2424  * @write: %TRUE if this is a write to the sysctl file
2425  * @buffer: the user buffer
2426  * @lenp: the size of the user buffer
2427  * @ppos: file position
2428  *
2429  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2430  * values from/to the user buffer, treated as an ASCII string.
2431  *
2432  * Returns 0 on success.
2433  */
2434 int proc_dointvec(struct ctl_table *table, int write,
2435 		     void __user *buffer, size_t *lenp, loff_t *ppos)
2436 {
2437 	return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
2438 }
2439 
2440 /**
2441  * proc_douintvec - read a vector of unsigned integers
2442  * @table: the sysctl table
2443  * @write: %TRUE if this is a write to the sysctl file
2444  * @buffer: the user buffer
2445  * @lenp: the size of the user buffer
2446  * @ppos: file position
2447  *
2448  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2449  * values from/to the user buffer, treated as an ASCII string.
2450  *
2451  * Returns 0 on success.
2452  */
2453 int proc_douintvec(struct ctl_table *table, int write,
2454 		     void __user *buffer, size_t *lenp, loff_t *ppos)
2455 {
2456 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
2457 				 do_proc_douintvec_conv, NULL);
2458 }
2459 
2460 /*
2461  * Taint values can only be increased
2462  * This means we can safely use a temporary.
2463  */
2464 static int proc_taint(struct ctl_table *table, int write,
2465 			       void __user *buffer, size_t *lenp, loff_t *ppos)
2466 {
2467 	struct ctl_table t;
2468 	unsigned long tmptaint = get_taint();
2469 	int err;
2470 
2471 	if (write && !capable(CAP_SYS_ADMIN))
2472 		return -EPERM;
2473 
2474 	t = *table;
2475 	t.data = &tmptaint;
2476 	err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2477 	if (err < 0)
2478 		return err;
2479 
2480 	if (write) {
2481 		/*
2482 		 * Poor man's atomic or. Not worth adding a primitive
2483 		 * to everyone's atomic.h for this
2484 		 */
2485 		int i;
2486 		for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2487 			if ((tmptaint >> i) & 1)
2488 				add_taint(i, LOCKDEP_STILL_OK);
2489 		}
2490 	}
2491 
2492 	return err;
2493 }
2494 
2495 #ifdef CONFIG_PRINTK
2496 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2497 				void __user *buffer, size_t *lenp, loff_t *ppos)
2498 {
2499 	if (write && !capable(CAP_SYS_ADMIN))
2500 		return -EPERM;
2501 
2502 	return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2503 }
2504 #endif
2505 
2506 /**
2507  * struct do_proc_dointvec_minmax_conv_param - proc_dointvec_minmax() range checking structure
2508  * @min: pointer to minimum allowable value
2509  * @max: pointer to maximum allowable value
2510  *
2511  * The do_proc_dointvec_minmax_conv_param structure provides the
2512  * minimum and maximum values for doing range checking for those sysctl
2513  * parameters that use the proc_dointvec_minmax() handler.
2514  */
2515 struct do_proc_dointvec_minmax_conv_param {
2516 	int *min;
2517 	int *max;
2518 };
2519 
2520 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2521 					int *valp,
2522 					int write, void *data)
2523 {
2524 	struct do_proc_dointvec_minmax_conv_param *param = data;
2525 	if (write) {
2526 		int val = *negp ? -*lvalp : *lvalp;
2527 		if ((param->min && *param->min > val) ||
2528 		    (param->max && *param->max < val))
2529 			return -EINVAL;
2530 		*valp = val;
2531 	} else {
2532 		int val = *valp;
2533 		if (val < 0) {
2534 			*negp = true;
2535 			*lvalp = -(unsigned long)val;
2536 		} else {
2537 			*negp = false;
2538 			*lvalp = (unsigned long)val;
2539 		}
2540 	}
2541 	return 0;
2542 }
2543 
2544 /**
2545  * proc_dointvec_minmax - read a vector of integers with min/max values
2546  * @table: the sysctl table
2547  * @write: %TRUE if this is a write to the sysctl file
2548  * @buffer: the user buffer
2549  * @lenp: the size of the user buffer
2550  * @ppos: file position
2551  *
2552  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2553  * values from/to the user buffer, treated as an ASCII string.
2554  *
2555  * This routine will ensure the values are within the range specified by
2556  * table->extra1 (min) and table->extra2 (max).
2557  *
2558  * Returns 0 on success or -EINVAL on write when the range check fails.
2559  */
2560 int proc_dointvec_minmax(struct ctl_table *table, int write,
2561 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2562 {
2563 	struct do_proc_dointvec_minmax_conv_param param = {
2564 		.min = (int *) table->extra1,
2565 		.max = (int *) table->extra2,
2566 	};
2567 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
2568 				do_proc_dointvec_minmax_conv, &param);
2569 }
2570 
2571 /**
2572  * struct do_proc_douintvec_minmax_conv_param - proc_douintvec_minmax() range checking structure
2573  * @min: pointer to minimum allowable value
2574  * @max: pointer to maximum allowable value
2575  *
2576  * The do_proc_douintvec_minmax_conv_param structure provides the
2577  * minimum and maximum values for doing range checking for those sysctl
2578  * parameters that use the proc_douintvec_minmax() handler.
2579  */
2580 struct do_proc_douintvec_minmax_conv_param {
2581 	unsigned int *min;
2582 	unsigned int *max;
2583 };
2584 
2585 static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
2586 					 unsigned int *valp,
2587 					 int write, void *data)
2588 {
2589 	struct do_proc_douintvec_minmax_conv_param *param = data;
2590 
2591 	if (write) {
2592 		unsigned int val = *lvalp;
2593 
2594 		if (*lvalp > UINT_MAX)
2595 			return -EINVAL;
2596 
2597 		if ((param->min && *param->min > val) ||
2598 		    (param->max && *param->max < val))
2599 			return -ERANGE;
2600 
2601 		*valp = val;
2602 	} else {
2603 		unsigned int val = *valp;
2604 		*lvalp = (unsigned long) val;
2605 	}
2606 
2607 	return 0;
2608 }
2609 
2610 /**
2611  * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
2612  * @table: the sysctl table
2613  * @write: %TRUE if this is a write to the sysctl file
2614  * @buffer: the user buffer
2615  * @lenp: the size of the user buffer
2616  * @ppos: file position
2617  *
2618  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2619  * values from/to the user buffer, treated as an ASCII string. Negative
2620  * strings are not allowed.
2621  *
2622  * This routine will ensure the values are within the range specified by
2623  * table->extra1 (min) and table->extra2 (max). There is a final sanity
2624  * check for UINT_MAX to avoid having to support wrap around uses from
2625  * userspace.
2626  *
2627  * Returns 0 on success or -ERANGE on write when the range check fails.
2628  */
2629 int proc_douintvec_minmax(struct ctl_table *table, int write,
2630 			  void __user *buffer, size_t *lenp, loff_t *ppos)
2631 {
2632 	struct do_proc_douintvec_minmax_conv_param param = {
2633 		.min = (unsigned int *) table->extra1,
2634 		.max = (unsigned int *) table->extra2,
2635 	};
2636 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
2637 				 do_proc_douintvec_minmax_conv, &param);
2638 }
2639 
2640 static int do_proc_dopipe_max_size_conv(unsigned long *lvalp,
2641 					unsigned int *valp,
2642 					int write, void *data)
2643 {
2644 	if (write) {
2645 		unsigned int val;
2646 
2647 		val = round_pipe_size(*lvalp);
2648 		if (val == 0)
2649 			return -EINVAL;
2650 
2651 		*valp = val;
2652 	} else {
2653 		unsigned int val = *valp;
2654 		*lvalp = (unsigned long) val;
2655 	}
2656 
2657 	return 0;
2658 }
2659 
2660 static int proc_dopipe_max_size(struct ctl_table *table, int write,
2661 				void __user *buffer, size_t *lenp, loff_t *ppos)
2662 {
2663 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
2664 				 do_proc_dopipe_max_size_conv, NULL);
2665 }
2666 
2667 static void validate_coredump_safety(void)
2668 {
2669 #ifdef CONFIG_COREDUMP
2670 	if (suid_dumpable == SUID_DUMP_ROOT &&
2671 	    core_pattern[0] != '/' && core_pattern[0] != '|') {
2672 		printk(KERN_WARNING
2673 "Unsafe core_pattern used with fs.suid_dumpable=2.\n"
2674 "Pipe handler or fully qualified core dump path required.\n"
2675 "Set kernel.core_pattern before fs.suid_dumpable.\n"
2676 		);
2677 	}
2678 #endif
2679 }
2680 
2681 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2682 		void __user *buffer, size_t *lenp, loff_t *ppos)
2683 {
2684 	int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2685 	if (!error)
2686 		validate_coredump_safety();
2687 	return error;
2688 }
2689 
2690 #ifdef CONFIG_COREDUMP
2691 static int proc_dostring_coredump(struct ctl_table *table, int write,
2692 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2693 {
2694 	int error = proc_dostring(table, write, buffer, lenp, ppos);
2695 	if (!error)
2696 		validate_coredump_safety();
2697 	return error;
2698 }
2699 #endif
2700 
2701 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2702 				     void __user *buffer,
2703 				     size_t *lenp, loff_t *ppos,
2704 				     unsigned long convmul,
2705 				     unsigned long convdiv)
2706 {
2707 	unsigned long *i, *min, *max;
2708 	int vleft, first = 1, err = 0;
2709 	size_t left;
2710 	char *kbuf = NULL, *p;
2711 
2712 	if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2713 		*lenp = 0;
2714 		return 0;
2715 	}
2716 
2717 	i = (unsigned long *) data;
2718 	min = (unsigned long *) table->extra1;
2719 	max = (unsigned long *) table->extra2;
2720 	vleft = table->maxlen / sizeof(unsigned long);
2721 	left = *lenp;
2722 
2723 	if (write) {
2724 		if (proc_first_pos_non_zero_ignore(ppos, table))
2725 			goto out;
2726 
2727 		if (left > PAGE_SIZE - 1)
2728 			left = PAGE_SIZE - 1;
2729 		p = kbuf = memdup_user_nul(buffer, left);
2730 		if (IS_ERR(kbuf))
2731 			return PTR_ERR(kbuf);
2732 	}
2733 
2734 	for (; left && vleft--; i++, first = 0) {
2735 		unsigned long val;
2736 
2737 		if (write) {
2738 			bool neg;
2739 
2740 			left -= proc_skip_spaces(&p);
2741 
2742 			err = proc_get_long(&p, &left, &val, &neg,
2743 					     proc_wspace_sep,
2744 					     sizeof(proc_wspace_sep), NULL);
2745 			if (err)
2746 				break;
2747 			if (neg)
2748 				continue;
2749 			val = convmul * val / convdiv;
2750 			if ((min && val < *min) || (max && val > *max))
2751 				continue;
2752 			*i = val;
2753 		} else {
2754 			val = convdiv * (*i) / convmul;
2755 			if (!first) {
2756 				err = proc_put_char(&buffer, &left, '\t');
2757 				if (err)
2758 					break;
2759 			}
2760 			err = proc_put_long(&buffer, &left, val, false);
2761 			if (err)
2762 				break;
2763 		}
2764 	}
2765 
2766 	if (!write && !first && left && !err)
2767 		err = proc_put_char(&buffer, &left, '\n');
2768 	if (write && !err)
2769 		left -= proc_skip_spaces(&p);
2770 	if (write) {
2771 		kfree(kbuf);
2772 		if (first)
2773 			return err ? : -EINVAL;
2774 	}
2775 	*lenp -= left;
2776 out:
2777 	*ppos += *lenp;
2778 	return err;
2779 }
2780 
2781 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2782 				     void __user *buffer,
2783 				     size_t *lenp, loff_t *ppos,
2784 				     unsigned long convmul,
2785 				     unsigned long convdiv)
2786 {
2787 	return __do_proc_doulongvec_minmax(table->data, table, write,
2788 			buffer, lenp, ppos, convmul, convdiv);
2789 }
2790 
2791 /**
2792  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2793  * @table: the sysctl table
2794  * @write: %TRUE if this is a write to the sysctl file
2795  * @buffer: the user buffer
2796  * @lenp: the size of the user buffer
2797  * @ppos: file position
2798  *
2799  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2800  * values from/to the user buffer, treated as an ASCII string.
2801  *
2802  * This routine will ensure the values are within the range specified by
2803  * table->extra1 (min) and table->extra2 (max).
2804  *
2805  * Returns 0 on success.
2806  */
2807 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2808 			   void __user *buffer, size_t *lenp, loff_t *ppos)
2809 {
2810     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2811 }
2812 
2813 /**
2814  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2815  * @table: the sysctl table
2816  * @write: %TRUE if this is a write to the sysctl file
2817  * @buffer: the user buffer
2818  * @lenp: the size of the user buffer
2819  * @ppos: file position
2820  *
2821  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2822  * values from/to the user buffer, treated as an ASCII string. The values
2823  * are treated as milliseconds, and converted to jiffies when they are stored.
2824  *
2825  * This routine will ensure the values are within the range specified by
2826  * table->extra1 (min) and table->extra2 (max).
2827  *
2828  * Returns 0 on success.
2829  */
2830 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2831 				      void __user *buffer,
2832 				      size_t *lenp, loff_t *ppos)
2833 {
2834     return do_proc_doulongvec_minmax(table, write, buffer,
2835 				     lenp, ppos, HZ, 1000l);
2836 }
2837 
2838 
2839 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2840 					 int *valp,
2841 					 int write, void *data)
2842 {
2843 	if (write) {
2844 		if (*lvalp > INT_MAX / HZ)
2845 			return 1;
2846 		*valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2847 	} else {
2848 		int val = *valp;
2849 		unsigned long lval;
2850 		if (val < 0) {
2851 			*negp = true;
2852 			lval = -(unsigned long)val;
2853 		} else {
2854 			*negp = false;
2855 			lval = (unsigned long)val;
2856 		}
2857 		*lvalp = lval / HZ;
2858 	}
2859 	return 0;
2860 }
2861 
2862 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2863 						int *valp,
2864 						int write, void *data)
2865 {
2866 	if (write) {
2867 		if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2868 			return 1;
2869 		*valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2870 	} else {
2871 		int val = *valp;
2872 		unsigned long lval;
2873 		if (val < 0) {
2874 			*negp = true;
2875 			lval = -(unsigned long)val;
2876 		} else {
2877 			*negp = false;
2878 			lval = (unsigned long)val;
2879 		}
2880 		*lvalp = jiffies_to_clock_t(lval);
2881 	}
2882 	return 0;
2883 }
2884 
2885 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2886 					    int *valp,
2887 					    int write, void *data)
2888 {
2889 	if (write) {
2890 		unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2891 
2892 		if (jif > INT_MAX)
2893 			return 1;
2894 		*valp = (int)jif;
2895 	} else {
2896 		int val = *valp;
2897 		unsigned long lval;
2898 		if (val < 0) {
2899 			*negp = true;
2900 			lval = -(unsigned long)val;
2901 		} else {
2902 			*negp = false;
2903 			lval = (unsigned long)val;
2904 		}
2905 		*lvalp = jiffies_to_msecs(lval);
2906 	}
2907 	return 0;
2908 }
2909 
2910 /**
2911  * proc_dointvec_jiffies - read a vector of integers as seconds
2912  * @table: the sysctl table
2913  * @write: %TRUE if this is a write to the sysctl file
2914  * @buffer: the user buffer
2915  * @lenp: the size of the user buffer
2916  * @ppos: file position
2917  *
2918  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2919  * values from/to the user buffer, treated as an ASCII string.
2920  * The values read are assumed to be in seconds, and are converted into
2921  * jiffies.
2922  *
2923  * Returns 0 on success.
2924  */
2925 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2926 			  void __user *buffer, size_t *lenp, loff_t *ppos)
2927 {
2928     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2929 		    	    do_proc_dointvec_jiffies_conv,NULL);
2930 }
2931 
2932 /**
2933  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2934  * @table: the sysctl table
2935  * @write: %TRUE if this is a write to the sysctl file
2936  * @buffer: the user buffer
2937  * @lenp: the size of the user buffer
2938  * @ppos: pointer to the file position
2939  *
2940  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2941  * values from/to the user buffer, treated as an ASCII string.
2942  * The values read are assumed to be in 1/USER_HZ seconds, and
2943  * are converted into jiffies.
2944  *
2945  * Returns 0 on success.
2946  */
2947 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2948 				 void __user *buffer, size_t *lenp, loff_t *ppos)
2949 {
2950     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2951 		    	    do_proc_dointvec_userhz_jiffies_conv,NULL);
2952 }
2953 
2954 /**
2955  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2956  * @table: the sysctl table
2957  * @write: %TRUE if this is a write to the sysctl file
2958  * @buffer: the user buffer
2959  * @lenp: the size of the user buffer
2960  * @ppos: file position
2961  * @ppos: the current position in the file
2962  *
2963  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2964  * values from/to the user buffer, treated as an ASCII string.
2965  * The values read are assumed to be in 1/1000 seconds, and
2966  * are converted into jiffies.
2967  *
2968  * Returns 0 on success.
2969  */
2970 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2971 			     void __user *buffer, size_t *lenp, loff_t *ppos)
2972 {
2973 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
2974 				do_proc_dointvec_ms_jiffies_conv, NULL);
2975 }
2976 
2977 static int proc_do_cad_pid(struct ctl_table *table, int write,
2978 			   void __user *buffer, size_t *lenp, loff_t *ppos)
2979 {
2980 	struct pid *new_pid;
2981 	pid_t tmp;
2982 	int r;
2983 
2984 	tmp = pid_vnr(cad_pid);
2985 
2986 	r = __do_proc_dointvec(&tmp, table, write, buffer,
2987 			       lenp, ppos, NULL, NULL);
2988 	if (r || !write)
2989 		return r;
2990 
2991 	new_pid = find_get_pid(tmp);
2992 	if (!new_pid)
2993 		return -ESRCH;
2994 
2995 	put_pid(xchg(&cad_pid, new_pid));
2996 	return 0;
2997 }
2998 
2999 /**
3000  * proc_do_large_bitmap - read/write from/to a large bitmap
3001  * @table: the sysctl table
3002  * @write: %TRUE if this is a write to the sysctl file
3003  * @buffer: the user buffer
3004  * @lenp: the size of the user buffer
3005  * @ppos: file position
3006  *
3007  * The bitmap is stored at table->data and the bitmap length (in bits)
3008  * in table->maxlen.
3009  *
3010  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
3011  * large bitmaps may be represented in a compact manner. Writing into
3012  * the file will clear the bitmap then update it with the given input.
3013  *
3014  * Returns 0 on success.
3015  */
3016 int proc_do_large_bitmap(struct ctl_table *table, int write,
3017 			 void __user *buffer, size_t *lenp, loff_t *ppos)
3018 {
3019 	int err = 0;
3020 	bool first = 1;
3021 	size_t left = *lenp;
3022 	unsigned long bitmap_len = table->maxlen;
3023 	unsigned long *bitmap = *(unsigned long **) table->data;
3024 	unsigned long *tmp_bitmap = NULL;
3025 	char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
3026 
3027 	if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
3028 		*lenp = 0;
3029 		return 0;
3030 	}
3031 
3032 	if (write) {
3033 		char *kbuf, *p;
3034 
3035 		if (left > PAGE_SIZE - 1)
3036 			left = PAGE_SIZE - 1;
3037 
3038 		p = kbuf = memdup_user_nul(buffer, left);
3039 		if (IS_ERR(kbuf))
3040 			return PTR_ERR(kbuf);
3041 
3042 		tmp_bitmap = kcalloc(BITS_TO_LONGS(bitmap_len),
3043 				     sizeof(unsigned long),
3044 				     GFP_KERNEL);
3045 		if (!tmp_bitmap) {
3046 			kfree(kbuf);
3047 			return -ENOMEM;
3048 		}
3049 		proc_skip_char(&p, &left, '\n');
3050 		while (!err && left) {
3051 			unsigned long val_a, val_b;
3052 			bool neg;
3053 
3054 			err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
3055 					     sizeof(tr_a), &c);
3056 			if (err)
3057 				break;
3058 			if (val_a >= bitmap_len || neg) {
3059 				err = -EINVAL;
3060 				break;
3061 			}
3062 
3063 			val_b = val_a;
3064 			if (left) {
3065 				p++;
3066 				left--;
3067 			}
3068 
3069 			if (c == '-') {
3070 				err = proc_get_long(&p, &left, &val_b,
3071 						     &neg, tr_b, sizeof(tr_b),
3072 						     &c);
3073 				if (err)
3074 					break;
3075 				if (val_b >= bitmap_len || neg ||
3076 				    val_a > val_b) {
3077 					err = -EINVAL;
3078 					break;
3079 				}
3080 				if (left) {
3081 					p++;
3082 					left--;
3083 				}
3084 			}
3085 
3086 			bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
3087 			first = 0;
3088 			proc_skip_char(&p, &left, '\n');
3089 		}
3090 		kfree(kbuf);
3091 	} else {
3092 		unsigned long bit_a, bit_b = 0;
3093 
3094 		while (left) {
3095 			bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
3096 			if (bit_a >= bitmap_len)
3097 				break;
3098 			bit_b = find_next_zero_bit(bitmap, bitmap_len,
3099 						   bit_a + 1) - 1;
3100 
3101 			if (!first) {
3102 				err = proc_put_char(&buffer, &left, ',');
3103 				if (err)
3104 					break;
3105 			}
3106 			err = proc_put_long(&buffer, &left, bit_a, false);
3107 			if (err)
3108 				break;
3109 			if (bit_a != bit_b) {
3110 				err = proc_put_char(&buffer, &left, '-');
3111 				if (err)
3112 					break;
3113 				err = proc_put_long(&buffer, &left, bit_b, false);
3114 				if (err)
3115 					break;
3116 			}
3117 
3118 			first = 0; bit_b++;
3119 		}
3120 		if (!err)
3121 			err = proc_put_char(&buffer, &left, '\n');
3122 	}
3123 
3124 	if (!err) {
3125 		if (write) {
3126 			if (*ppos)
3127 				bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
3128 			else
3129 				bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
3130 		}
3131 		*lenp -= left;
3132 		*ppos += *lenp;
3133 	}
3134 
3135 	kfree(tmp_bitmap);
3136 	return err;
3137 }
3138 
3139 #else /* CONFIG_PROC_SYSCTL */
3140 
3141 int proc_dostring(struct ctl_table *table, int write,
3142 		  void __user *buffer, size_t *lenp, loff_t *ppos)
3143 {
3144 	return -ENOSYS;
3145 }
3146 
3147 int proc_dointvec(struct ctl_table *table, int write,
3148 		  void __user *buffer, size_t *lenp, loff_t *ppos)
3149 {
3150 	return -ENOSYS;
3151 }
3152 
3153 int proc_douintvec(struct ctl_table *table, int write,
3154 		  void __user *buffer, size_t *lenp, loff_t *ppos)
3155 {
3156 	return -ENOSYS;
3157 }
3158 
3159 int proc_dointvec_minmax(struct ctl_table *table, int write,
3160 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3161 {
3162 	return -ENOSYS;
3163 }
3164 
3165 int proc_douintvec_minmax(struct ctl_table *table, int write,
3166 			  void __user *buffer, size_t *lenp, loff_t *ppos)
3167 {
3168 	return -ENOSYS;
3169 }
3170 
3171 int proc_dointvec_jiffies(struct ctl_table *table, int write,
3172 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3173 {
3174 	return -ENOSYS;
3175 }
3176 
3177 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
3178 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3179 {
3180 	return -ENOSYS;
3181 }
3182 
3183 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
3184 			     void __user *buffer, size_t *lenp, loff_t *ppos)
3185 {
3186 	return -ENOSYS;
3187 }
3188 
3189 int proc_doulongvec_minmax(struct ctl_table *table, int write,
3190 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3191 {
3192 	return -ENOSYS;
3193 }
3194 
3195 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
3196 				      void __user *buffer,
3197 				      size_t *lenp, loff_t *ppos)
3198 {
3199     return -ENOSYS;
3200 }
3201 
3202 
3203 #endif /* CONFIG_PROC_SYSCTL */
3204 
3205 /*
3206  * No sense putting this after each symbol definition, twice,
3207  * exception granted :-)
3208  */
3209 EXPORT_SYMBOL(proc_dointvec);
3210 EXPORT_SYMBOL(proc_douintvec);
3211 EXPORT_SYMBOL(proc_dointvec_jiffies);
3212 EXPORT_SYMBOL(proc_dointvec_minmax);
3213 EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
3214 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3215 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3216 EXPORT_SYMBOL(proc_dostring);
3217 EXPORT_SYMBOL(proc_doulongvec_minmax);
3218 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3219