xref: /openbmc/linux/kernel/sysctl.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * sysctl.c: General linux system control interface
4  *
5  * Begun 24 March 1995, Stephen Tweedie
6  * Added /proc support, Dec 1995
7  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
8  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
9  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
10  * Dynamic registration fixes, Stephen Tweedie.
11  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
12  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
13  *  Horn.
14  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
15  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
16  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
17  *  Wendling.
18  * The list_for_each() macro wasn't appropriate for the sysctl loop.
19  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
20  */
21 
22 #include <linux/module.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/panic.h>
30 #include <linux/printk.h>
31 #include <linux/proc_fs.h>
32 #include <linux/security.h>
33 #include <linux/ctype.h>
34 #include <linux/kmemleak.h>
35 #include <linux/filter.h>
36 #include <linux/fs.h>
37 #include <linux/init.h>
38 #include <linux/kernel.h>
39 #include <linux/kobject.h>
40 #include <linux/net.h>
41 #include <linux/sysrq.h>
42 #include <linux/highuid.h>
43 #include <linux/writeback.h>
44 #include <linux/ratelimit.h>
45 #include <linux/compaction.h>
46 #include <linux/hugetlb.h>
47 #include <linux/initrd.h>
48 #include <linux/key.h>
49 #include <linux/times.h>
50 #include <linux/limits.h>
51 #include <linux/dcache.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/oom.h>
60 #include <linux/kmod.h>
61 #include <linux/capability.h>
62 #include <linux/binfmts.h>
63 #include <linux/sched/sysctl.h>
64 #include <linux/kexec.h>
65 #include <linux/bpf.h>
66 #include <linux/mount.h>
67 #include <linux/userfaultfd_k.h>
68 #include <linux/latencytop.h>
69 #include <linux/pid.h>
70 #include <linux/delayacct.h>
71 
72 #include "../lib/kstrtox.h"
73 
74 #include <linux/uaccess.h>
75 #include <asm/processor.h>
76 
77 #ifdef CONFIG_X86
78 #include <asm/nmi.h>
79 #include <asm/stacktrace.h>
80 #include <asm/io.h>
81 #endif
82 #ifdef CONFIG_SPARC
83 #include <asm/setup.h>
84 #endif
85 #ifdef CONFIG_BSD_PROCESS_ACCT
86 #include <linux/acct.h>
87 #endif
88 #ifdef CONFIG_RT_MUTEXES
89 #include <linux/rtmutex.h>
90 #endif
91 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
92 #include <linux/lockdep.h>
93 #endif
94 
95 #if defined(CONFIG_SYSCTL)
96 
97 /* Constants used for minimum and  maximum */
98 
99 #ifdef CONFIG_PERF_EVENTS
100 static const int six_hundred_forty_kb = 640 * 1024;
101 #endif
102 
103 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
104 static const unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
105 
106 static const int ngroups_max = NGROUPS_MAX;
107 static const int cap_last_cap = CAP_LAST_CAP;
108 
109 #ifdef CONFIG_PROC_SYSCTL
110 
111 /**
112  * enum sysctl_writes_mode - supported sysctl write modes
113  *
114  * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
115  *	to be written, and multiple writes on the same sysctl file descriptor
116  *	will rewrite the sysctl value, regardless of file position. No warning
117  *	is issued when the initial position is not 0.
118  * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
119  *	not 0.
120  * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
121  *	file position 0 and the value must be fully contained in the buffer
122  *	sent to the write syscall. If dealing with strings respect the file
123  *	position, but restrict this to the max length of the buffer, anything
124  *	passed the max length will be ignored. Multiple writes will append
125  *	to the buffer.
126  *
127  * These write modes control how current file position affects the behavior of
128  * updating sysctl values through the proc interface on each write.
129  */
130 enum sysctl_writes_mode {
131 	SYSCTL_WRITES_LEGACY		= -1,
132 	SYSCTL_WRITES_WARN		= 0,
133 	SYSCTL_WRITES_STRICT		= 1,
134 };
135 
136 static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
137 #endif /* CONFIG_PROC_SYSCTL */
138 
139 #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
140     defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
141 int sysctl_legacy_va_layout;
142 #endif
143 
144 #ifdef CONFIG_COMPACTION
145 /* min_extfrag_threshold is SYSCTL_ZERO */;
146 static const int max_extfrag_threshold = 1000;
147 #endif
148 
149 #endif /* CONFIG_SYSCTL */
150 
151 #if defined(CONFIG_BPF_SYSCALL) && defined(CONFIG_SYSCTL)
152 static int bpf_stats_handler(struct ctl_table *table, int write,
153 			     void *buffer, size_t *lenp, loff_t *ppos)
154 {
155 	struct static_key *key = (struct static_key *)table->data;
156 	static int saved_val;
157 	int val, ret;
158 	struct ctl_table tmp = {
159 		.data   = &val,
160 		.maxlen = sizeof(val),
161 		.mode   = table->mode,
162 		.extra1 = SYSCTL_ZERO,
163 		.extra2 = SYSCTL_ONE,
164 	};
165 
166 	if (write && !capable(CAP_SYS_ADMIN))
167 		return -EPERM;
168 
169 	mutex_lock(&bpf_stats_enabled_mutex);
170 	val = saved_val;
171 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
172 	if (write && !ret && val != saved_val) {
173 		if (val)
174 			static_key_slow_inc(key);
175 		else
176 			static_key_slow_dec(key);
177 		saved_val = val;
178 	}
179 	mutex_unlock(&bpf_stats_enabled_mutex);
180 	return ret;
181 }
182 
183 static int bpf_unpriv_handler(struct ctl_table *table, int write,
184 			      void *buffer, size_t *lenp, loff_t *ppos)
185 {
186 	int ret, unpriv_enable = *(int *)table->data;
187 	bool locked_state = unpriv_enable == 1;
188 	struct ctl_table tmp = *table;
189 
190 	if (write && !capable(CAP_SYS_ADMIN))
191 		return -EPERM;
192 
193 	tmp.data = &unpriv_enable;
194 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
195 	if (write && !ret) {
196 		if (locked_state && unpriv_enable != 1)
197 			return -EPERM;
198 		*(int *)table->data = unpriv_enable;
199 	}
200 	return ret;
201 }
202 #endif /* CONFIG_BPF_SYSCALL && CONFIG_SYSCTL */
203 
204 /*
205  * /proc/sys support
206  */
207 
208 #ifdef CONFIG_PROC_SYSCTL
209 
210 static int _proc_do_string(char *data, int maxlen, int write,
211 		char *buffer, size_t *lenp, loff_t *ppos)
212 {
213 	size_t len;
214 	char c, *p;
215 
216 	if (!data || !maxlen || !*lenp) {
217 		*lenp = 0;
218 		return 0;
219 	}
220 
221 	if (write) {
222 		if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
223 			/* Only continue writes not past the end of buffer. */
224 			len = strlen(data);
225 			if (len > maxlen - 1)
226 				len = maxlen - 1;
227 
228 			if (*ppos > len)
229 				return 0;
230 			len = *ppos;
231 		} else {
232 			/* Start writing from beginning of buffer. */
233 			len = 0;
234 		}
235 
236 		*ppos += *lenp;
237 		p = buffer;
238 		while ((p - buffer) < *lenp && len < maxlen - 1) {
239 			c = *(p++);
240 			if (c == 0 || c == '\n')
241 				break;
242 			data[len++] = c;
243 		}
244 		data[len] = 0;
245 	} else {
246 		len = strlen(data);
247 		if (len > maxlen)
248 			len = maxlen;
249 
250 		if (*ppos > len) {
251 			*lenp = 0;
252 			return 0;
253 		}
254 
255 		data += *ppos;
256 		len  -= *ppos;
257 
258 		if (len > *lenp)
259 			len = *lenp;
260 		if (len)
261 			memcpy(buffer, data, len);
262 		if (len < *lenp) {
263 			buffer[len] = '\n';
264 			len++;
265 		}
266 		*lenp = len;
267 		*ppos += len;
268 	}
269 	return 0;
270 }
271 
272 static void warn_sysctl_write(struct ctl_table *table)
273 {
274 	pr_warn_once("%s wrote to %s when file position was not 0!\n"
275 		"This will not be supported in the future. To silence this\n"
276 		"warning, set kernel.sysctl_writes_strict = -1\n",
277 		current->comm, table->procname);
278 }
279 
280 /**
281  * proc_first_pos_non_zero_ignore - check if first position is allowed
282  * @ppos: file position
283  * @table: the sysctl table
284  *
285  * Returns true if the first position is non-zero and the sysctl_writes_strict
286  * mode indicates this is not allowed for numeric input types. String proc
287  * handlers can ignore the return value.
288  */
289 static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
290 					   struct ctl_table *table)
291 {
292 	if (!*ppos)
293 		return false;
294 
295 	switch (sysctl_writes_strict) {
296 	case SYSCTL_WRITES_STRICT:
297 		return true;
298 	case SYSCTL_WRITES_WARN:
299 		warn_sysctl_write(table);
300 		return false;
301 	default:
302 		return false;
303 	}
304 }
305 
306 /**
307  * proc_dostring - read a string sysctl
308  * @table: the sysctl table
309  * @write: %TRUE if this is a write to the sysctl file
310  * @buffer: the user buffer
311  * @lenp: the size of the user buffer
312  * @ppos: file position
313  *
314  * Reads/writes a string from/to the user buffer. If the kernel
315  * buffer provided is not large enough to hold the string, the
316  * string is truncated. The copied string is %NULL-terminated.
317  * If the string is being read by the user process, it is copied
318  * and a newline '\n' is added. It is truncated if the buffer is
319  * not large enough.
320  *
321  * Returns 0 on success.
322  */
323 int proc_dostring(struct ctl_table *table, int write,
324 		  void *buffer, size_t *lenp, loff_t *ppos)
325 {
326 	if (write)
327 		proc_first_pos_non_zero_ignore(ppos, table);
328 
329 	return _proc_do_string(table->data, table->maxlen, write, buffer, lenp,
330 			ppos);
331 }
332 
333 static size_t proc_skip_spaces(char **buf)
334 {
335 	size_t ret;
336 	char *tmp = skip_spaces(*buf);
337 	ret = tmp - *buf;
338 	*buf = tmp;
339 	return ret;
340 }
341 
342 static void proc_skip_char(char **buf, size_t *size, const char v)
343 {
344 	while (*size) {
345 		if (**buf != v)
346 			break;
347 		(*size)--;
348 		(*buf)++;
349 	}
350 }
351 
352 /**
353  * strtoul_lenient - parse an ASCII formatted integer from a buffer and only
354  *                   fail on overflow
355  *
356  * @cp: kernel buffer containing the string to parse
357  * @endp: pointer to store the trailing characters
358  * @base: the base to use
359  * @res: where the parsed integer will be stored
360  *
361  * In case of success 0 is returned and @res will contain the parsed integer,
362  * @endp will hold any trailing characters.
363  * This function will fail the parse on overflow. If there wasn't an overflow
364  * the function will defer the decision what characters count as invalid to the
365  * caller.
366  */
367 static int strtoul_lenient(const char *cp, char **endp, unsigned int base,
368 			   unsigned long *res)
369 {
370 	unsigned long long result;
371 	unsigned int rv;
372 
373 	cp = _parse_integer_fixup_radix(cp, &base);
374 	rv = _parse_integer(cp, base, &result);
375 	if ((rv & KSTRTOX_OVERFLOW) || (result != (unsigned long)result))
376 		return -ERANGE;
377 
378 	cp += rv;
379 
380 	if (endp)
381 		*endp = (char *)cp;
382 
383 	*res = (unsigned long)result;
384 	return 0;
385 }
386 
387 #define TMPBUFLEN 22
388 /**
389  * proc_get_long - reads an ASCII formatted integer from a user buffer
390  *
391  * @buf: a kernel buffer
392  * @size: size of the kernel buffer
393  * @val: this is where the number will be stored
394  * @neg: set to %TRUE if number is negative
395  * @perm_tr: a vector which contains the allowed trailers
396  * @perm_tr_len: size of the perm_tr vector
397  * @tr: pointer to store the trailer character
398  *
399  * In case of success %0 is returned and @buf and @size are updated with
400  * the amount of bytes read. If @tr is non-NULL and a trailing
401  * character exists (size is non-zero after returning from this
402  * function), @tr is updated with the trailing character.
403  */
404 static int proc_get_long(char **buf, size_t *size,
405 			  unsigned long *val, bool *neg,
406 			  const char *perm_tr, unsigned perm_tr_len, char *tr)
407 {
408 	int len;
409 	char *p, tmp[TMPBUFLEN];
410 
411 	if (!*size)
412 		return -EINVAL;
413 
414 	len = *size;
415 	if (len > TMPBUFLEN - 1)
416 		len = TMPBUFLEN - 1;
417 
418 	memcpy(tmp, *buf, len);
419 
420 	tmp[len] = 0;
421 	p = tmp;
422 	if (*p == '-' && *size > 1) {
423 		*neg = true;
424 		p++;
425 	} else
426 		*neg = false;
427 	if (!isdigit(*p))
428 		return -EINVAL;
429 
430 	if (strtoul_lenient(p, &p, 0, val))
431 		return -EINVAL;
432 
433 	len = p - tmp;
434 
435 	/* We don't know if the next char is whitespace thus we may accept
436 	 * invalid integers (e.g. 1234...a) or two integers instead of one
437 	 * (e.g. 123...1). So lets not allow such large numbers. */
438 	if (len == TMPBUFLEN - 1)
439 		return -EINVAL;
440 
441 	if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
442 		return -EINVAL;
443 
444 	if (tr && (len < *size))
445 		*tr = *p;
446 
447 	*buf += len;
448 	*size -= len;
449 
450 	return 0;
451 }
452 
453 /**
454  * proc_put_long - converts an integer to a decimal ASCII formatted string
455  *
456  * @buf: the user buffer
457  * @size: the size of the user buffer
458  * @val: the integer to be converted
459  * @neg: sign of the number, %TRUE for negative
460  *
461  * In case of success @buf and @size are updated with the amount of bytes
462  * written.
463  */
464 static void proc_put_long(void **buf, size_t *size, unsigned long val, bool neg)
465 {
466 	int len;
467 	char tmp[TMPBUFLEN], *p = tmp;
468 
469 	sprintf(p, "%s%lu", neg ? "-" : "", val);
470 	len = strlen(tmp);
471 	if (len > *size)
472 		len = *size;
473 	memcpy(*buf, tmp, len);
474 	*size -= len;
475 	*buf += len;
476 }
477 #undef TMPBUFLEN
478 
479 static void proc_put_char(void **buf, size_t *size, char c)
480 {
481 	if (*size) {
482 		char **buffer = (char **)buf;
483 		**buffer = c;
484 
485 		(*size)--;
486 		(*buffer)++;
487 		*buf = *buffer;
488 	}
489 }
490 
491 static int do_proc_dobool_conv(bool *negp, unsigned long *lvalp,
492 				int *valp,
493 				int write, void *data)
494 {
495 	if (write) {
496 		*(bool *)valp = *lvalp;
497 	} else {
498 		int val = *(bool *)valp;
499 
500 		*lvalp = (unsigned long)val;
501 		*negp = false;
502 	}
503 	return 0;
504 }
505 
506 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
507 				 int *valp,
508 				 int write, void *data)
509 {
510 	if (write) {
511 		if (*negp) {
512 			if (*lvalp > (unsigned long) INT_MAX + 1)
513 				return -EINVAL;
514 			*valp = -*lvalp;
515 		} else {
516 			if (*lvalp > (unsigned long) INT_MAX)
517 				return -EINVAL;
518 			*valp = *lvalp;
519 		}
520 	} else {
521 		int val = *valp;
522 		if (val < 0) {
523 			*negp = true;
524 			*lvalp = -(unsigned long)val;
525 		} else {
526 			*negp = false;
527 			*lvalp = (unsigned long)val;
528 		}
529 	}
530 	return 0;
531 }
532 
533 static int do_proc_douintvec_conv(unsigned long *lvalp,
534 				  unsigned int *valp,
535 				  int write, void *data)
536 {
537 	if (write) {
538 		if (*lvalp > UINT_MAX)
539 			return -EINVAL;
540 		*valp = *lvalp;
541 	} else {
542 		unsigned int val = *valp;
543 		*lvalp = (unsigned long)val;
544 	}
545 	return 0;
546 }
547 
548 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
549 
550 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
551 		  int write, void *buffer,
552 		  size_t *lenp, loff_t *ppos,
553 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
554 			      int write, void *data),
555 		  void *data)
556 {
557 	int *i, vleft, first = 1, err = 0;
558 	size_t left;
559 	char *p;
560 
561 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
562 		*lenp = 0;
563 		return 0;
564 	}
565 
566 	i = (int *) tbl_data;
567 	vleft = table->maxlen / sizeof(*i);
568 	left = *lenp;
569 
570 	if (!conv)
571 		conv = do_proc_dointvec_conv;
572 
573 	if (write) {
574 		if (proc_first_pos_non_zero_ignore(ppos, table))
575 			goto out;
576 
577 		if (left > PAGE_SIZE - 1)
578 			left = PAGE_SIZE - 1;
579 		p = buffer;
580 	}
581 
582 	for (; left && vleft--; i++, first=0) {
583 		unsigned long lval;
584 		bool neg;
585 
586 		if (write) {
587 			left -= proc_skip_spaces(&p);
588 
589 			if (!left)
590 				break;
591 			err = proc_get_long(&p, &left, &lval, &neg,
592 					     proc_wspace_sep,
593 					     sizeof(proc_wspace_sep), NULL);
594 			if (err)
595 				break;
596 			if (conv(&neg, &lval, i, 1, data)) {
597 				err = -EINVAL;
598 				break;
599 			}
600 		} else {
601 			if (conv(&neg, &lval, i, 0, data)) {
602 				err = -EINVAL;
603 				break;
604 			}
605 			if (!first)
606 				proc_put_char(&buffer, &left, '\t');
607 			proc_put_long(&buffer, &left, lval, neg);
608 		}
609 	}
610 
611 	if (!write && !first && left && !err)
612 		proc_put_char(&buffer, &left, '\n');
613 	if (write && !err && left)
614 		left -= proc_skip_spaces(&p);
615 	if (write && first)
616 		return err ? : -EINVAL;
617 	*lenp -= left;
618 out:
619 	*ppos += *lenp;
620 	return err;
621 }
622 
623 static int do_proc_dointvec(struct ctl_table *table, int write,
624 		  void *buffer, size_t *lenp, loff_t *ppos,
625 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
626 			      int write, void *data),
627 		  void *data)
628 {
629 	return __do_proc_dointvec(table->data, table, write,
630 			buffer, lenp, ppos, conv, data);
631 }
632 
633 static int do_proc_douintvec_w(unsigned int *tbl_data,
634 			       struct ctl_table *table,
635 			       void *buffer,
636 			       size_t *lenp, loff_t *ppos,
637 			       int (*conv)(unsigned long *lvalp,
638 					   unsigned int *valp,
639 					   int write, void *data),
640 			       void *data)
641 {
642 	unsigned long lval;
643 	int err = 0;
644 	size_t left;
645 	bool neg;
646 	char *p = buffer;
647 
648 	left = *lenp;
649 
650 	if (proc_first_pos_non_zero_ignore(ppos, table))
651 		goto bail_early;
652 
653 	if (left > PAGE_SIZE - 1)
654 		left = PAGE_SIZE - 1;
655 
656 	left -= proc_skip_spaces(&p);
657 	if (!left) {
658 		err = -EINVAL;
659 		goto out_free;
660 	}
661 
662 	err = proc_get_long(&p, &left, &lval, &neg,
663 			     proc_wspace_sep,
664 			     sizeof(proc_wspace_sep), NULL);
665 	if (err || neg) {
666 		err = -EINVAL;
667 		goto out_free;
668 	}
669 
670 	if (conv(&lval, tbl_data, 1, data)) {
671 		err = -EINVAL;
672 		goto out_free;
673 	}
674 
675 	if (!err && left)
676 		left -= proc_skip_spaces(&p);
677 
678 out_free:
679 	if (err)
680 		return -EINVAL;
681 
682 	return 0;
683 
684 	/* This is in keeping with old __do_proc_dointvec() */
685 bail_early:
686 	*ppos += *lenp;
687 	return err;
688 }
689 
690 static int do_proc_douintvec_r(unsigned int *tbl_data, void *buffer,
691 			       size_t *lenp, loff_t *ppos,
692 			       int (*conv)(unsigned long *lvalp,
693 					   unsigned int *valp,
694 					   int write, void *data),
695 			       void *data)
696 {
697 	unsigned long lval;
698 	int err = 0;
699 	size_t left;
700 
701 	left = *lenp;
702 
703 	if (conv(&lval, tbl_data, 0, data)) {
704 		err = -EINVAL;
705 		goto out;
706 	}
707 
708 	proc_put_long(&buffer, &left, lval, false);
709 	if (!left)
710 		goto out;
711 
712 	proc_put_char(&buffer, &left, '\n');
713 
714 out:
715 	*lenp -= left;
716 	*ppos += *lenp;
717 
718 	return err;
719 }
720 
721 static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
722 			       int write, void *buffer,
723 			       size_t *lenp, loff_t *ppos,
724 			       int (*conv)(unsigned long *lvalp,
725 					   unsigned int *valp,
726 					   int write, void *data),
727 			       void *data)
728 {
729 	unsigned int *i, vleft;
730 
731 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
732 		*lenp = 0;
733 		return 0;
734 	}
735 
736 	i = (unsigned int *) tbl_data;
737 	vleft = table->maxlen / sizeof(*i);
738 
739 	/*
740 	 * Arrays are not supported, keep this simple. *Do not* add
741 	 * support for them.
742 	 */
743 	if (vleft != 1) {
744 		*lenp = 0;
745 		return -EINVAL;
746 	}
747 
748 	if (!conv)
749 		conv = do_proc_douintvec_conv;
750 
751 	if (write)
752 		return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
753 					   conv, data);
754 	return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
755 }
756 
757 int do_proc_douintvec(struct ctl_table *table, int write,
758 		      void *buffer, size_t *lenp, loff_t *ppos,
759 		      int (*conv)(unsigned long *lvalp,
760 				  unsigned int *valp,
761 				  int write, void *data),
762 		      void *data)
763 {
764 	return __do_proc_douintvec(table->data, table, write,
765 				   buffer, lenp, ppos, conv, data);
766 }
767 
768 /**
769  * proc_dobool - read/write a bool
770  * @table: the sysctl table
771  * @write: %TRUE if this is a write to the sysctl file
772  * @buffer: the user buffer
773  * @lenp: the size of the user buffer
774  * @ppos: file position
775  *
776  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
777  * values from/to the user buffer, treated as an ASCII string.
778  *
779  * Returns 0 on success.
780  */
781 int proc_dobool(struct ctl_table *table, int write, void *buffer,
782 		size_t *lenp, loff_t *ppos)
783 {
784 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
785 				do_proc_dobool_conv, NULL);
786 }
787 
788 /**
789  * proc_dointvec - read a vector of integers
790  * @table: the sysctl table
791  * @write: %TRUE if this is a write to the sysctl file
792  * @buffer: the user buffer
793  * @lenp: the size of the user buffer
794  * @ppos: file position
795  *
796  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
797  * values from/to the user buffer, treated as an ASCII string.
798  *
799  * Returns 0 on success.
800  */
801 int proc_dointvec(struct ctl_table *table, int write, void *buffer,
802 		  size_t *lenp, loff_t *ppos)
803 {
804 	return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
805 }
806 
807 #ifdef CONFIG_COMPACTION
808 static int proc_dointvec_minmax_warn_RT_change(struct ctl_table *table,
809 		int write, void *buffer, size_t *lenp, loff_t *ppos)
810 {
811 	int ret, old;
812 
813 	if (!IS_ENABLED(CONFIG_PREEMPT_RT) || !write)
814 		return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
815 
816 	old = *(int *)table->data;
817 	ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
818 	if (ret)
819 		return ret;
820 	if (old != *(int *)table->data)
821 		pr_warn_once("sysctl attribute %s changed by %s[%d]\n",
822 			     table->procname, current->comm,
823 			     task_pid_nr(current));
824 	return ret;
825 }
826 #endif
827 
828 /**
829  * proc_douintvec - read a vector of unsigned integers
830  * @table: the sysctl table
831  * @write: %TRUE if this is a write to the sysctl file
832  * @buffer: the user buffer
833  * @lenp: the size of the user buffer
834  * @ppos: file position
835  *
836  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
837  * values from/to the user buffer, treated as an ASCII string.
838  *
839  * Returns 0 on success.
840  */
841 int proc_douintvec(struct ctl_table *table, int write, void *buffer,
842 		size_t *lenp, loff_t *ppos)
843 {
844 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
845 				 do_proc_douintvec_conv, NULL);
846 }
847 
848 /*
849  * Taint values can only be increased
850  * This means we can safely use a temporary.
851  */
852 static int proc_taint(struct ctl_table *table, int write,
853 			       void *buffer, size_t *lenp, loff_t *ppos)
854 {
855 	struct ctl_table t;
856 	unsigned long tmptaint = get_taint();
857 	int err;
858 
859 	if (write && !capable(CAP_SYS_ADMIN))
860 		return -EPERM;
861 
862 	t = *table;
863 	t.data = &tmptaint;
864 	err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
865 	if (err < 0)
866 		return err;
867 
868 	if (write) {
869 		int i;
870 
871 		/*
872 		 * If we are relying on panic_on_taint not producing
873 		 * false positives due to userspace input, bail out
874 		 * before setting the requested taint flags.
875 		 */
876 		if (panic_on_taint_nousertaint && (tmptaint & panic_on_taint))
877 			return -EINVAL;
878 
879 		/*
880 		 * Poor man's atomic or. Not worth adding a primitive
881 		 * to everyone's atomic.h for this
882 		 */
883 		for (i = 0; i < TAINT_FLAGS_COUNT; i++)
884 			if ((1UL << i) & tmptaint)
885 				add_taint(i, LOCKDEP_STILL_OK);
886 	}
887 
888 	return err;
889 }
890 
891 /**
892  * struct do_proc_dointvec_minmax_conv_param - proc_dointvec_minmax() range checking structure
893  * @min: pointer to minimum allowable value
894  * @max: pointer to maximum allowable value
895  *
896  * The do_proc_dointvec_minmax_conv_param structure provides the
897  * minimum and maximum values for doing range checking for those sysctl
898  * parameters that use the proc_dointvec_minmax() handler.
899  */
900 struct do_proc_dointvec_minmax_conv_param {
901 	int *min;
902 	int *max;
903 };
904 
905 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
906 					int *valp,
907 					int write, void *data)
908 {
909 	int tmp, ret;
910 	struct do_proc_dointvec_minmax_conv_param *param = data;
911 	/*
912 	 * If writing, first do so via a temporary local int so we can
913 	 * bounds-check it before touching *valp.
914 	 */
915 	int *ip = write ? &tmp : valp;
916 
917 	ret = do_proc_dointvec_conv(negp, lvalp, ip, write, data);
918 	if (ret)
919 		return ret;
920 
921 	if (write) {
922 		if ((param->min && *param->min > tmp) ||
923 		    (param->max && *param->max < tmp))
924 			return -EINVAL;
925 		*valp = tmp;
926 	}
927 
928 	return 0;
929 }
930 
931 /**
932  * proc_dointvec_minmax - read a vector of integers with min/max values
933  * @table: the sysctl table
934  * @write: %TRUE if this is a write to the sysctl file
935  * @buffer: the user buffer
936  * @lenp: the size of the user buffer
937  * @ppos: file position
938  *
939  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
940  * values from/to the user buffer, treated as an ASCII string.
941  *
942  * This routine will ensure the values are within the range specified by
943  * table->extra1 (min) and table->extra2 (max).
944  *
945  * Returns 0 on success or -EINVAL on write when the range check fails.
946  */
947 int proc_dointvec_minmax(struct ctl_table *table, int write,
948 		  void *buffer, size_t *lenp, loff_t *ppos)
949 {
950 	struct do_proc_dointvec_minmax_conv_param param = {
951 		.min = (int *) table->extra1,
952 		.max = (int *) table->extra2,
953 	};
954 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
955 				do_proc_dointvec_minmax_conv, &param);
956 }
957 
958 /**
959  * struct do_proc_douintvec_minmax_conv_param - proc_douintvec_minmax() range checking structure
960  * @min: pointer to minimum allowable value
961  * @max: pointer to maximum allowable value
962  *
963  * The do_proc_douintvec_minmax_conv_param structure provides the
964  * minimum and maximum values for doing range checking for those sysctl
965  * parameters that use the proc_douintvec_minmax() handler.
966  */
967 struct do_proc_douintvec_minmax_conv_param {
968 	unsigned int *min;
969 	unsigned int *max;
970 };
971 
972 static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
973 					 unsigned int *valp,
974 					 int write, void *data)
975 {
976 	int ret;
977 	unsigned int tmp;
978 	struct do_proc_douintvec_minmax_conv_param *param = data;
979 	/* write via temporary local uint for bounds-checking */
980 	unsigned int *up = write ? &tmp : valp;
981 
982 	ret = do_proc_douintvec_conv(lvalp, up, write, data);
983 	if (ret)
984 		return ret;
985 
986 	if (write) {
987 		if ((param->min && *param->min > tmp) ||
988 		    (param->max && *param->max < tmp))
989 			return -ERANGE;
990 
991 		*valp = tmp;
992 	}
993 
994 	return 0;
995 }
996 
997 /**
998  * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
999  * @table: the sysctl table
1000  * @write: %TRUE if this is a write to the sysctl file
1001  * @buffer: the user buffer
1002  * @lenp: the size of the user buffer
1003  * @ppos: file position
1004  *
1005  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
1006  * values from/to the user buffer, treated as an ASCII string. Negative
1007  * strings are not allowed.
1008  *
1009  * This routine will ensure the values are within the range specified by
1010  * table->extra1 (min) and table->extra2 (max). There is a final sanity
1011  * check for UINT_MAX to avoid having to support wrap around uses from
1012  * userspace.
1013  *
1014  * Returns 0 on success or -ERANGE on write when the range check fails.
1015  */
1016 int proc_douintvec_minmax(struct ctl_table *table, int write,
1017 			  void *buffer, size_t *lenp, loff_t *ppos)
1018 {
1019 	struct do_proc_douintvec_minmax_conv_param param = {
1020 		.min = (unsigned int *) table->extra1,
1021 		.max = (unsigned int *) table->extra2,
1022 	};
1023 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
1024 				 do_proc_douintvec_minmax_conv, &param);
1025 }
1026 
1027 /**
1028  * proc_dou8vec_minmax - read a vector of unsigned chars with min/max values
1029  * @table: the sysctl table
1030  * @write: %TRUE if this is a write to the sysctl file
1031  * @buffer: the user buffer
1032  * @lenp: the size of the user buffer
1033  * @ppos: file position
1034  *
1035  * Reads/writes up to table->maxlen/sizeof(u8) unsigned chars
1036  * values from/to the user buffer, treated as an ASCII string. Negative
1037  * strings are not allowed.
1038  *
1039  * This routine will ensure the values are within the range specified by
1040  * table->extra1 (min) and table->extra2 (max).
1041  *
1042  * Returns 0 on success or an error on write when the range check fails.
1043  */
1044 int proc_dou8vec_minmax(struct ctl_table *table, int write,
1045 			void *buffer, size_t *lenp, loff_t *ppos)
1046 {
1047 	struct ctl_table tmp;
1048 	unsigned int min = 0, max = 255U, val;
1049 	u8 *data = table->data;
1050 	struct do_proc_douintvec_minmax_conv_param param = {
1051 		.min = &min,
1052 		.max = &max,
1053 	};
1054 	int res;
1055 
1056 	/* Do not support arrays yet. */
1057 	if (table->maxlen != sizeof(u8))
1058 		return -EINVAL;
1059 
1060 	if (table->extra1) {
1061 		min = *(unsigned int *) table->extra1;
1062 		if (min > 255U)
1063 			return -EINVAL;
1064 	}
1065 	if (table->extra2) {
1066 		max = *(unsigned int *) table->extra2;
1067 		if (max > 255U)
1068 			return -EINVAL;
1069 	}
1070 
1071 	tmp = *table;
1072 
1073 	tmp.maxlen = sizeof(val);
1074 	tmp.data = &val;
1075 	val = *data;
1076 	res = do_proc_douintvec(&tmp, write, buffer, lenp, ppos,
1077 				do_proc_douintvec_minmax_conv, &param);
1078 	if (res)
1079 		return res;
1080 	if (write)
1081 		*data = val;
1082 	return 0;
1083 }
1084 EXPORT_SYMBOL_GPL(proc_dou8vec_minmax);
1085 
1086 #ifdef CONFIG_MAGIC_SYSRQ
1087 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
1088 				void *buffer, size_t *lenp, loff_t *ppos)
1089 {
1090 	int tmp, ret;
1091 
1092 	tmp = sysrq_mask();
1093 
1094 	ret = __do_proc_dointvec(&tmp, table, write, buffer,
1095 			       lenp, ppos, NULL, NULL);
1096 	if (ret || !write)
1097 		return ret;
1098 
1099 	if (write)
1100 		sysrq_toggle_support(tmp);
1101 
1102 	return 0;
1103 }
1104 #endif
1105 
1106 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table,
1107 		int write, void *buffer, size_t *lenp, loff_t *ppos,
1108 		unsigned long convmul, unsigned long convdiv)
1109 {
1110 	unsigned long *i, *min, *max;
1111 	int vleft, first = 1, err = 0;
1112 	size_t left;
1113 	char *p;
1114 
1115 	if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
1116 		*lenp = 0;
1117 		return 0;
1118 	}
1119 
1120 	i = (unsigned long *) data;
1121 	min = (unsigned long *) table->extra1;
1122 	max = (unsigned long *) table->extra2;
1123 	vleft = table->maxlen / sizeof(unsigned long);
1124 	left = *lenp;
1125 
1126 	if (write) {
1127 		if (proc_first_pos_non_zero_ignore(ppos, table))
1128 			goto out;
1129 
1130 		if (left > PAGE_SIZE - 1)
1131 			left = PAGE_SIZE - 1;
1132 		p = buffer;
1133 	}
1134 
1135 	for (; left && vleft--; i++, first = 0) {
1136 		unsigned long val;
1137 
1138 		if (write) {
1139 			bool neg;
1140 
1141 			left -= proc_skip_spaces(&p);
1142 			if (!left)
1143 				break;
1144 
1145 			err = proc_get_long(&p, &left, &val, &neg,
1146 					     proc_wspace_sep,
1147 					     sizeof(proc_wspace_sep), NULL);
1148 			if (err || neg) {
1149 				err = -EINVAL;
1150 				break;
1151 			}
1152 
1153 			val = convmul * val / convdiv;
1154 			if ((min && val < *min) || (max && val > *max)) {
1155 				err = -EINVAL;
1156 				break;
1157 			}
1158 			*i = val;
1159 		} else {
1160 			val = convdiv * (*i) / convmul;
1161 			if (!first)
1162 				proc_put_char(&buffer, &left, '\t');
1163 			proc_put_long(&buffer, &left, val, false);
1164 		}
1165 	}
1166 
1167 	if (!write && !first && left && !err)
1168 		proc_put_char(&buffer, &left, '\n');
1169 	if (write && !err)
1170 		left -= proc_skip_spaces(&p);
1171 	if (write && first)
1172 		return err ? : -EINVAL;
1173 	*lenp -= left;
1174 out:
1175 	*ppos += *lenp;
1176 	return err;
1177 }
1178 
1179 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
1180 		void *buffer, size_t *lenp, loff_t *ppos, unsigned long convmul,
1181 		unsigned long convdiv)
1182 {
1183 	return __do_proc_doulongvec_minmax(table->data, table, write,
1184 			buffer, lenp, ppos, convmul, convdiv);
1185 }
1186 
1187 /**
1188  * proc_doulongvec_minmax - read a vector of long integers with min/max values
1189  * @table: the sysctl table
1190  * @write: %TRUE if this is a write to the sysctl file
1191  * @buffer: the user buffer
1192  * @lenp: the size of the user buffer
1193  * @ppos: file position
1194  *
1195  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1196  * values from/to the user buffer, treated as an ASCII string.
1197  *
1198  * This routine will ensure the values are within the range specified by
1199  * table->extra1 (min) and table->extra2 (max).
1200  *
1201  * Returns 0 on success.
1202  */
1203 int proc_doulongvec_minmax(struct ctl_table *table, int write,
1204 			   void *buffer, size_t *lenp, loff_t *ppos)
1205 {
1206     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
1207 }
1208 
1209 /**
1210  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1211  * @table: the sysctl table
1212  * @write: %TRUE if this is a write to the sysctl file
1213  * @buffer: the user buffer
1214  * @lenp: the size of the user buffer
1215  * @ppos: file position
1216  *
1217  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1218  * values from/to the user buffer, treated as an ASCII string. The values
1219  * are treated as milliseconds, and converted to jiffies when they are stored.
1220  *
1221  * This routine will ensure the values are within the range specified by
1222  * table->extra1 (min) and table->extra2 (max).
1223  *
1224  * Returns 0 on success.
1225  */
1226 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
1227 				      void *buffer, size_t *lenp, loff_t *ppos)
1228 {
1229     return do_proc_doulongvec_minmax(table, write, buffer,
1230 				     lenp, ppos, HZ, 1000l);
1231 }
1232 
1233 
1234 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
1235 					 int *valp,
1236 					 int write, void *data)
1237 {
1238 	if (write) {
1239 		if (*lvalp > INT_MAX / HZ)
1240 			return 1;
1241 		*valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
1242 	} else {
1243 		int val = *valp;
1244 		unsigned long lval;
1245 		if (val < 0) {
1246 			*negp = true;
1247 			lval = -(unsigned long)val;
1248 		} else {
1249 			*negp = false;
1250 			lval = (unsigned long)val;
1251 		}
1252 		*lvalp = lval / HZ;
1253 	}
1254 	return 0;
1255 }
1256 
1257 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
1258 						int *valp,
1259 						int write, void *data)
1260 {
1261 	if (write) {
1262 		if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
1263 			return 1;
1264 		*valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
1265 	} else {
1266 		int val = *valp;
1267 		unsigned long lval;
1268 		if (val < 0) {
1269 			*negp = true;
1270 			lval = -(unsigned long)val;
1271 		} else {
1272 			*negp = false;
1273 			lval = (unsigned long)val;
1274 		}
1275 		*lvalp = jiffies_to_clock_t(lval);
1276 	}
1277 	return 0;
1278 }
1279 
1280 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
1281 					    int *valp,
1282 					    int write, void *data)
1283 {
1284 	if (write) {
1285 		unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
1286 
1287 		if (jif > INT_MAX)
1288 			return 1;
1289 		*valp = (int)jif;
1290 	} else {
1291 		int val = *valp;
1292 		unsigned long lval;
1293 		if (val < 0) {
1294 			*negp = true;
1295 			lval = -(unsigned long)val;
1296 		} else {
1297 			*negp = false;
1298 			lval = (unsigned long)val;
1299 		}
1300 		*lvalp = jiffies_to_msecs(lval);
1301 	}
1302 	return 0;
1303 }
1304 
1305 /**
1306  * proc_dointvec_jiffies - read a vector of integers as seconds
1307  * @table: the sysctl table
1308  * @write: %TRUE if this is a write to the sysctl file
1309  * @buffer: the user buffer
1310  * @lenp: the size of the user buffer
1311  * @ppos: file position
1312  *
1313  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1314  * values from/to the user buffer, treated as an ASCII string.
1315  * The values read are assumed to be in seconds, and are converted into
1316  * jiffies.
1317  *
1318  * Returns 0 on success.
1319  */
1320 int proc_dointvec_jiffies(struct ctl_table *table, int write,
1321 			  void *buffer, size_t *lenp, loff_t *ppos)
1322 {
1323     return do_proc_dointvec(table,write,buffer,lenp,ppos,
1324 		    	    do_proc_dointvec_jiffies_conv,NULL);
1325 }
1326 
1327 /**
1328  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
1329  * @table: the sysctl table
1330  * @write: %TRUE if this is a write to the sysctl file
1331  * @buffer: the user buffer
1332  * @lenp: the size of the user buffer
1333  * @ppos: pointer to the file position
1334  *
1335  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1336  * values from/to the user buffer, treated as an ASCII string.
1337  * The values read are assumed to be in 1/USER_HZ seconds, and
1338  * are converted into jiffies.
1339  *
1340  * Returns 0 on success.
1341  */
1342 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
1343 				 void *buffer, size_t *lenp, loff_t *ppos)
1344 {
1345     return do_proc_dointvec(table,write,buffer,lenp,ppos,
1346 		    	    do_proc_dointvec_userhz_jiffies_conv,NULL);
1347 }
1348 
1349 /**
1350  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
1351  * @table: the sysctl table
1352  * @write: %TRUE if this is a write to the sysctl file
1353  * @buffer: the user buffer
1354  * @lenp: the size of the user buffer
1355  * @ppos: file position
1356  * @ppos: the current position in the file
1357  *
1358  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1359  * values from/to the user buffer, treated as an ASCII string.
1360  * The values read are assumed to be in 1/1000 seconds, and
1361  * are converted into jiffies.
1362  *
1363  * Returns 0 on success.
1364  */
1365 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, void *buffer,
1366 		size_t *lenp, loff_t *ppos)
1367 {
1368 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
1369 				do_proc_dointvec_ms_jiffies_conv, NULL);
1370 }
1371 
1372 static int proc_do_cad_pid(struct ctl_table *table, int write, void *buffer,
1373 		size_t *lenp, loff_t *ppos)
1374 {
1375 	struct pid *new_pid;
1376 	pid_t tmp;
1377 	int r;
1378 
1379 	tmp = pid_vnr(cad_pid);
1380 
1381 	r = __do_proc_dointvec(&tmp, table, write, buffer,
1382 			       lenp, ppos, NULL, NULL);
1383 	if (r || !write)
1384 		return r;
1385 
1386 	new_pid = find_get_pid(tmp);
1387 	if (!new_pid)
1388 		return -ESRCH;
1389 
1390 	put_pid(xchg(&cad_pid, new_pid));
1391 	return 0;
1392 }
1393 
1394 /**
1395  * proc_do_large_bitmap - read/write from/to a large bitmap
1396  * @table: the sysctl table
1397  * @write: %TRUE if this is a write to the sysctl file
1398  * @buffer: the user buffer
1399  * @lenp: the size of the user buffer
1400  * @ppos: file position
1401  *
1402  * The bitmap is stored at table->data and the bitmap length (in bits)
1403  * in table->maxlen.
1404  *
1405  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
1406  * large bitmaps may be represented in a compact manner. Writing into
1407  * the file will clear the bitmap then update it with the given input.
1408  *
1409  * Returns 0 on success.
1410  */
1411 int proc_do_large_bitmap(struct ctl_table *table, int write,
1412 			 void *buffer, size_t *lenp, loff_t *ppos)
1413 {
1414 	int err = 0;
1415 	size_t left = *lenp;
1416 	unsigned long bitmap_len = table->maxlen;
1417 	unsigned long *bitmap = *(unsigned long **) table->data;
1418 	unsigned long *tmp_bitmap = NULL;
1419 	char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
1420 
1421 	if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
1422 		*lenp = 0;
1423 		return 0;
1424 	}
1425 
1426 	if (write) {
1427 		char *p = buffer;
1428 		size_t skipped = 0;
1429 
1430 		if (left > PAGE_SIZE - 1) {
1431 			left = PAGE_SIZE - 1;
1432 			/* How much of the buffer we'll skip this pass */
1433 			skipped = *lenp - left;
1434 		}
1435 
1436 		tmp_bitmap = bitmap_zalloc(bitmap_len, GFP_KERNEL);
1437 		if (!tmp_bitmap)
1438 			return -ENOMEM;
1439 		proc_skip_char(&p, &left, '\n');
1440 		while (!err && left) {
1441 			unsigned long val_a, val_b;
1442 			bool neg;
1443 			size_t saved_left;
1444 
1445 			/* In case we stop parsing mid-number, we can reset */
1446 			saved_left = left;
1447 			err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
1448 					     sizeof(tr_a), &c);
1449 			/*
1450 			 * If we consumed the entirety of a truncated buffer or
1451 			 * only one char is left (may be a "-"), then stop here,
1452 			 * reset, & come back for more.
1453 			 */
1454 			if ((left <= 1) && skipped) {
1455 				left = saved_left;
1456 				break;
1457 			}
1458 
1459 			if (err)
1460 				break;
1461 			if (val_a >= bitmap_len || neg) {
1462 				err = -EINVAL;
1463 				break;
1464 			}
1465 
1466 			val_b = val_a;
1467 			if (left) {
1468 				p++;
1469 				left--;
1470 			}
1471 
1472 			if (c == '-') {
1473 				err = proc_get_long(&p, &left, &val_b,
1474 						     &neg, tr_b, sizeof(tr_b),
1475 						     &c);
1476 				/*
1477 				 * If we consumed all of a truncated buffer or
1478 				 * then stop here, reset, & come back for more.
1479 				 */
1480 				if (!left && skipped) {
1481 					left = saved_left;
1482 					break;
1483 				}
1484 
1485 				if (err)
1486 					break;
1487 				if (val_b >= bitmap_len || neg ||
1488 				    val_a > val_b) {
1489 					err = -EINVAL;
1490 					break;
1491 				}
1492 				if (left) {
1493 					p++;
1494 					left--;
1495 				}
1496 			}
1497 
1498 			bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
1499 			proc_skip_char(&p, &left, '\n');
1500 		}
1501 		left += skipped;
1502 	} else {
1503 		unsigned long bit_a, bit_b = 0;
1504 		bool first = 1;
1505 
1506 		while (left) {
1507 			bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
1508 			if (bit_a >= bitmap_len)
1509 				break;
1510 			bit_b = find_next_zero_bit(bitmap, bitmap_len,
1511 						   bit_a + 1) - 1;
1512 
1513 			if (!first)
1514 				proc_put_char(&buffer, &left, ',');
1515 			proc_put_long(&buffer, &left, bit_a, false);
1516 			if (bit_a != bit_b) {
1517 				proc_put_char(&buffer, &left, '-');
1518 				proc_put_long(&buffer, &left, bit_b, false);
1519 			}
1520 
1521 			first = 0; bit_b++;
1522 		}
1523 		proc_put_char(&buffer, &left, '\n');
1524 	}
1525 
1526 	if (!err) {
1527 		if (write) {
1528 			if (*ppos)
1529 				bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
1530 			else
1531 				bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
1532 		}
1533 		*lenp -= left;
1534 		*ppos += *lenp;
1535 	}
1536 
1537 	bitmap_free(tmp_bitmap);
1538 	return err;
1539 }
1540 
1541 #else /* CONFIG_PROC_SYSCTL */
1542 
1543 int proc_dostring(struct ctl_table *table, int write,
1544 		  void *buffer, size_t *lenp, loff_t *ppos)
1545 {
1546 	return -ENOSYS;
1547 }
1548 
1549 int proc_dobool(struct ctl_table *table, int write,
1550 		void *buffer, size_t *lenp, loff_t *ppos)
1551 {
1552 	return -ENOSYS;
1553 }
1554 
1555 int proc_dointvec(struct ctl_table *table, int write,
1556 		  void *buffer, size_t *lenp, loff_t *ppos)
1557 {
1558 	return -ENOSYS;
1559 }
1560 
1561 int proc_douintvec(struct ctl_table *table, int write,
1562 		  void *buffer, size_t *lenp, loff_t *ppos)
1563 {
1564 	return -ENOSYS;
1565 }
1566 
1567 int proc_dointvec_minmax(struct ctl_table *table, int write,
1568 		    void *buffer, size_t *lenp, loff_t *ppos)
1569 {
1570 	return -ENOSYS;
1571 }
1572 
1573 int proc_douintvec_minmax(struct ctl_table *table, int write,
1574 			  void *buffer, size_t *lenp, loff_t *ppos)
1575 {
1576 	return -ENOSYS;
1577 }
1578 
1579 int proc_dou8vec_minmax(struct ctl_table *table, int write,
1580 			void *buffer, size_t *lenp, loff_t *ppos)
1581 {
1582 	return -ENOSYS;
1583 }
1584 
1585 int proc_dointvec_jiffies(struct ctl_table *table, int write,
1586 		    void *buffer, size_t *lenp, loff_t *ppos)
1587 {
1588 	return -ENOSYS;
1589 }
1590 
1591 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
1592 		    void *buffer, size_t *lenp, loff_t *ppos)
1593 {
1594 	return -ENOSYS;
1595 }
1596 
1597 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
1598 			     void *buffer, size_t *lenp, loff_t *ppos)
1599 {
1600 	return -ENOSYS;
1601 }
1602 
1603 int proc_doulongvec_minmax(struct ctl_table *table, int write,
1604 		    void *buffer, size_t *lenp, loff_t *ppos)
1605 {
1606 	return -ENOSYS;
1607 }
1608 
1609 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
1610 				      void *buffer, size_t *lenp, loff_t *ppos)
1611 {
1612 	return -ENOSYS;
1613 }
1614 
1615 int proc_do_large_bitmap(struct ctl_table *table, int write,
1616 			 void *buffer, size_t *lenp, loff_t *ppos)
1617 {
1618 	return -ENOSYS;
1619 }
1620 
1621 #endif /* CONFIG_PROC_SYSCTL */
1622 
1623 #if defined(CONFIG_SYSCTL)
1624 int proc_do_static_key(struct ctl_table *table, int write,
1625 		       void *buffer, size_t *lenp, loff_t *ppos)
1626 {
1627 	struct static_key *key = (struct static_key *)table->data;
1628 	static DEFINE_MUTEX(static_key_mutex);
1629 	int val, ret;
1630 	struct ctl_table tmp = {
1631 		.data   = &val,
1632 		.maxlen = sizeof(val),
1633 		.mode   = table->mode,
1634 		.extra1 = SYSCTL_ZERO,
1635 		.extra2 = SYSCTL_ONE,
1636 	};
1637 
1638 	if (write && !capable(CAP_SYS_ADMIN))
1639 		return -EPERM;
1640 
1641 	mutex_lock(&static_key_mutex);
1642 	val = static_key_enabled(key);
1643 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
1644 	if (write && !ret) {
1645 		if (val)
1646 			static_key_enable(key);
1647 		else
1648 			static_key_disable(key);
1649 	}
1650 	mutex_unlock(&static_key_mutex);
1651 	return ret;
1652 }
1653 
1654 static struct ctl_table kern_table[] = {
1655 	{
1656 		.procname	= "sched_child_runs_first",
1657 		.data		= &sysctl_sched_child_runs_first,
1658 		.maxlen		= sizeof(unsigned int),
1659 		.mode		= 0644,
1660 		.proc_handler	= proc_dointvec,
1661 	},
1662 #ifdef CONFIG_SCHEDSTATS
1663 	{
1664 		.procname	= "sched_schedstats",
1665 		.data		= NULL,
1666 		.maxlen		= sizeof(unsigned int),
1667 		.mode		= 0644,
1668 		.proc_handler	= sysctl_schedstats,
1669 		.extra1		= SYSCTL_ZERO,
1670 		.extra2		= SYSCTL_ONE,
1671 	},
1672 #endif /* CONFIG_SCHEDSTATS */
1673 #ifdef CONFIG_TASK_DELAY_ACCT
1674 	{
1675 		.procname	= "task_delayacct",
1676 		.data		= NULL,
1677 		.maxlen		= sizeof(unsigned int),
1678 		.mode		= 0644,
1679 		.proc_handler	= sysctl_delayacct,
1680 		.extra1		= SYSCTL_ZERO,
1681 		.extra2		= SYSCTL_ONE,
1682 	},
1683 #endif /* CONFIG_TASK_DELAY_ACCT */
1684 #ifdef CONFIG_NUMA_BALANCING
1685 	{
1686 		.procname	= "numa_balancing",
1687 		.data		= NULL, /* filled in by handler */
1688 		.maxlen		= sizeof(unsigned int),
1689 		.mode		= 0644,
1690 		.proc_handler	= sysctl_numa_balancing,
1691 		.extra1		= SYSCTL_ZERO,
1692 		.extra2		= SYSCTL_ONE,
1693 	},
1694 #endif /* CONFIG_NUMA_BALANCING */
1695 	{
1696 		.procname	= "sched_rt_period_us",
1697 		.data		= &sysctl_sched_rt_period,
1698 		.maxlen		= sizeof(unsigned int),
1699 		.mode		= 0644,
1700 		.proc_handler	= sched_rt_handler,
1701 	},
1702 	{
1703 		.procname	= "sched_rt_runtime_us",
1704 		.data		= &sysctl_sched_rt_runtime,
1705 		.maxlen		= sizeof(int),
1706 		.mode		= 0644,
1707 		.proc_handler	= sched_rt_handler,
1708 	},
1709 	{
1710 		.procname	= "sched_deadline_period_max_us",
1711 		.data		= &sysctl_sched_dl_period_max,
1712 		.maxlen		= sizeof(unsigned int),
1713 		.mode		= 0644,
1714 		.proc_handler	= proc_dointvec,
1715 	},
1716 	{
1717 		.procname	= "sched_deadline_period_min_us",
1718 		.data		= &sysctl_sched_dl_period_min,
1719 		.maxlen		= sizeof(unsigned int),
1720 		.mode		= 0644,
1721 		.proc_handler	= proc_dointvec,
1722 	},
1723 	{
1724 		.procname	= "sched_rr_timeslice_ms",
1725 		.data		= &sysctl_sched_rr_timeslice,
1726 		.maxlen		= sizeof(int),
1727 		.mode		= 0644,
1728 		.proc_handler	= sched_rr_handler,
1729 	},
1730 #ifdef CONFIG_UCLAMP_TASK
1731 	{
1732 		.procname	= "sched_util_clamp_min",
1733 		.data		= &sysctl_sched_uclamp_util_min,
1734 		.maxlen		= sizeof(unsigned int),
1735 		.mode		= 0644,
1736 		.proc_handler	= sysctl_sched_uclamp_handler,
1737 	},
1738 	{
1739 		.procname	= "sched_util_clamp_max",
1740 		.data		= &sysctl_sched_uclamp_util_max,
1741 		.maxlen		= sizeof(unsigned int),
1742 		.mode		= 0644,
1743 		.proc_handler	= sysctl_sched_uclamp_handler,
1744 	},
1745 	{
1746 		.procname	= "sched_util_clamp_min_rt_default",
1747 		.data		= &sysctl_sched_uclamp_util_min_rt_default,
1748 		.maxlen		= sizeof(unsigned int),
1749 		.mode		= 0644,
1750 		.proc_handler	= sysctl_sched_uclamp_handler,
1751 	},
1752 #endif
1753 #ifdef CONFIG_SCHED_AUTOGROUP
1754 	{
1755 		.procname	= "sched_autogroup_enabled",
1756 		.data		= &sysctl_sched_autogroup_enabled,
1757 		.maxlen		= sizeof(unsigned int),
1758 		.mode		= 0644,
1759 		.proc_handler	= proc_dointvec_minmax,
1760 		.extra1		= SYSCTL_ZERO,
1761 		.extra2		= SYSCTL_ONE,
1762 	},
1763 #endif
1764 #ifdef CONFIG_CFS_BANDWIDTH
1765 	{
1766 		.procname	= "sched_cfs_bandwidth_slice_us",
1767 		.data		= &sysctl_sched_cfs_bandwidth_slice,
1768 		.maxlen		= sizeof(unsigned int),
1769 		.mode		= 0644,
1770 		.proc_handler	= proc_dointvec_minmax,
1771 		.extra1		= SYSCTL_ONE,
1772 	},
1773 #endif
1774 #if defined(CONFIG_ENERGY_MODEL) && defined(CONFIG_CPU_FREQ_GOV_SCHEDUTIL)
1775 	{
1776 		.procname	= "sched_energy_aware",
1777 		.data		= &sysctl_sched_energy_aware,
1778 		.maxlen		= sizeof(unsigned int),
1779 		.mode		= 0644,
1780 		.proc_handler	= sched_energy_aware_handler,
1781 		.extra1		= SYSCTL_ZERO,
1782 		.extra2		= SYSCTL_ONE,
1783 	},
1784 #endif
1785 #ifdef CONFIG_PROVE_LOCKING
1786 	{
1787 		.procname	= "prove_locking",
1788 		.data		= &prove_locking,
1789 		.maxlen		= sizeof(int),
1790 		.mode		= 0644,
1791 		.proc_handler	= proc_dointvec,
1792 	},
1793 #endif
1794 #ifdef CONFIG_LOCK_STAT
1795 	{
1796 		.procname	= "lock_stat",
1797 		.data		= &lock_stat,
1798 		.maxlen		= sizeof(int),
1799 		.mode		= 0644,
1800 		.proc_handler	= proc_dointvec,
1801 	},
1802 #endif
1803 	{
1804 		.procname	= "panic",
1805 		.data		= &panic_timeout,
1806 		.maxlen		= sizeof(int),
1807 		.mode		= 0644,
1808 		.proc_handler	= proc_dointvec,
1809 	},
1810 #ifdef CONFIG_PROC_SYSCTL
1811 	{
1812 		.procname	= "tainted",
1813 		.maxlen 	= sizeof(long),
1814 		.mode		= 0644,
1815 		.proc_handler	= proc_taint,
1816 	},
1817 	{
1818 		.procname	= "sysctl_writes_strict",
1819 		.data		= &sysctl_writes_strict,
1820 		.maxlen		= sizeof(int),
1821 		.mode		= 0644,
1822 		.proc_handler	= proc_dointvec_minmax,
1823 		.extra1		= SYSCTL_NEG_ONE,
1824 		.extra2		= SYSCTL_ONE,
1825 	},
1826 #endif
1827 #ifdef CONFIG_LATENCYTOP
1828 	{
1829 		.procname	= "latencytop",
1830 		.data		= &latencytop_enabled,
1831 		.maxlen		= sizeof(int),
1832 		.mode		= 0644,
1833 		.proc_handler	= sysctl_latencytop,
1834 	},
1835 #endif
1836 #ifdef CONFIG_BLK_DEV_INITRD
1837 	{
1838 		.procname	= "real-root-dev",
1839 		.data		= &real_root_dev,
1840 		.maxlen		= sizeof(int),
1841 		.mode		= 0644,
1842 		.proc_handler	= proc_dointvec,
1843 	},
1844 #endif
1845 	{
1846 		.procname	= "print-fatal-signals",
1847 		.data		= &print_fatal_signals,
1848 		.maxlen		= sizeof(int),
1849 		.mode		= 0644,
1850 		.proc_handler	= proc_dointvec,
1851 	},
1852 #ifdef CONFIG_SPARC
1853 	{
1854 		.procname	= "reboot-cmd",
1855 		.data		= reboot_command,
1856 		.maxlen		= 256,
1857 		.mode		= 0644,
1858 		.proc_handler	= proc_dostring,
1859 	},
1860 	{
1861 		.procname	= "stop-a",
1862 		.data		= &stop_a_enabled,
1863 		.maxlen		= sizeof (int),
1864 		.mode		= 0644,
1865 		.proc_handler	= proc_dointvec,
1866 	},
1867 	{
1868 		.procname	= "scons-poweroff",
1869 		.data		= &scons_pwroff,
1870 		.maxlen		= sizeof (int),
1871 		.mode		= 0644,
1872 		.proc_handler	= proc_dointvec,
1873 	},
1874 #endif
1875 #ifdef CONFIG_SPARC64
1876 	{
1877 		.procname	= "tsb-ratio",
1878 		.data		= &sysctl_tsb_ratio,
1879 		.maxlen		= sizeof (int),
1880 		.mode		= 0644,
1881 		.proc_handler	= proc_dointvec,
1882 	},
1883 #endif
1884 #ifdef CONFIG_PARISC
1885 	{
1886 		.procname	= "soft-power",
1887 		.data		= &pwrsw_enabled,
1888 		.maxlen		= sizeof (int),
1889 		.mode		= 0644,
1890 		.proc_handler	= proc_dointvec,
1891 	},
1892 #endif
1893 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
1894 	{
1895 		.procname	= "unaligned-trap",
1896 		.data		= &unaligned_enabled,
1897 		.maxlen		= sizeof (int),
1898 		.mode		= 0644,
1899 		.proc_handler	= proc_dointvec,
1900 	},
1901 #endif
1902 	{
1903 		.procname	= "ctrl-alt-del",
1904 		.data		= &C_A_D,
1905 		.maxlen		= sizeof(int),
1906 		.mode		= 0644,
1907 		.proc_handler	= proc_dointvec,
1908 	},
1909 #ifdef CONFIG_FUNCTION_TRACER
1910 	{
1911 		.procname	= "ftrace_enabled",
1912 		.data		= &ftrace_enabled,
1913 		.maxlen		= sizeof(int),
1914 		.mode		= 0644,
1915 		.proc_handler	= ftrace_enable_sysctl,
1916 	},
1917 #endif
1918 #ifdef CONFIG_STACK_TRACER
1919 	{
1920 		.procname	= "stack_tracer_enabled",
1921 		.data		= &stack_tracer_enabled,
1922 		.maxlen		= sizeof(int),
1923 		.mode		= 0644,
1924 		.proc_handler	= stack_trace_sysctl,
1925 	},
1926 #endif
1927 #ifdef CONFIG_TRACING
1928 	{
1929 		.procname	= "ftrace_dump_on_oops",
1930 		.data		= &ftrace_dump_on_oops,
1931 		.maxlen		= sizeof(int),
1932 		.mode		= 0644,
1933 		.proc_handler	= proc_dointvec,
1934 	},
1935 	{
1936 		.procname	= "traceoff_on_warning",
1937 		.data		= &__disable_trace_on_warning,
1938 		.maxlen		= sizeof(__disable_trace_on_warning),
1939 		.mode		= 0644,
1940 		.proc_handler	= proc_dointvec,
1941 	},
1942 	{
1943 		.procname	= "tracepoint_printk",
1944 		.data		= &tracepoint_printk,
1945 		.maxlen		= sizeof(tracepoint_printk),
1946 		.mode		= 0644,
1947 		.proc_handler	= tracepoint_printk_sysctl,
1948 	},
1949 #endif
1950 #ifdef CONFIG_KEXEC_CORE
1951 	{
1952 		.procname	= "kexec_load_disabled",
1953 		.data		= &kexec_load_disabled,
1954 		.maxlen		= sizeof(int),
1955 		.mode		= 0644,
1956 		/* only handle a transition from default "0" to "1" */
1957 		.proc_handler	= proc_dointvec_minmax,
1958 		.extra1		= SYSCTL_ONE,
1959 		.extra2		= SYSCTL_ONE,
1960 	},
1961 #endif
1962 #ifdef CONFIG_MODULES
1963 	{
1964 		.procname	= "modprobe",
1965 		.data		= &modprobe_path,
1966 		.maxlen		= KMOD_PATH_LEN,
1967 		.mode		= 0644,
1968 		.proc_handler	= proc_dostring,
1969 	},
1970 	{
1971 		.procname	= "modules_disabled",
1972 		.data		= &modules_disabled,
1973 		.maxlen		= sizeof(int),
1974 		.mode		= 0644,
1975 		/* only handle a transition from default "0" to "1" */
1976 		.proc_handler	= proc_dointvec_minmax,
1977 		.extra1		= SYSCTL_ONE,
1978 		.extra2		= SYSCTL_ONE,
1979 	},
1980 #endif
1981 #ifdef CONFIG_UEVENT_HELPER
1982 	{
1983 		.procname	= "hotplug",
1984 		.data		= &uevent_helper,
1985 		.maxlen		= UEVENT_HELPER_PATH_LEN,
1986 		.mode		= 0644,
1987 		.proc_handler	= proc_dostring,
1988 	},
1989 #endif
1990 #ifdef CONFIG_BSD_PROCESS_ACCT
1991 	{
1992 		.procname	= "acct",
1993 		.data		= &acct_parm,
1994 		.maxlen		= 3*sizeof(int),
1995 		.mode		= 0644,
1996 		.proc_handler	= proc_dointvec,
1997 	},
1998 #endif
1999 #ifdef CONFIG_MAGIC_SYSRQ
2000 	{
2001 		.procname	= "sysrq",
2002 		.data		= NULL,
2003 		.maxlen		= sizeof (int),
2004 		.mode		= 0644,
2005 		.proc_handler	= sysrq_sysctl_handler,
2006 	},
2007 #endif
2008 #ifdef CONFIG_PROC_SYSCTL
2009 	{
2010 		.procname	= "cad_pid",
2011 		.data		= NULL,
2012 		.maxlen		= sizeof (int),
2013 		.mode		= 0600,
2014 		.proc_handler	= proc_do_cad_pid,
2015 	},
2016 #endif
2017 	{
2018 		.procname	= "threads-max",
2019 		.data		= NULL,
2020 		.maxlen		= sizeof(int),
2021 		.mode		= 0644,
2022 		.proc_handler	= sysctl_max_threads,
2023 	},
2024 	{
2025 		.procname	= "usermodehelper",
2026 		.mode		= 0555,
2027 		.child		= usermodehelper_table,
2028 	},
2029 	{
2030 		.procname	= "overflowuid",
2031 		.data		= &overflowuid,
2032 		.maxlen		= sizeof(int),
2033 		.mode		= 0644,
2034 		.proc_handler	= proc_dointvec_minmax,
2035 		.extra1		= SYSCTL_ZERO,
2036 		.extra2		= SYSCTL_MAXOLDUID,
2037 	},
2038 	{
2039 		.procname	= "overflowgid",
2040 		.data		= &overflowgid,
2041 		.maxlen		= sizeof(int),
2042 		.mode		= 0644,
2043 		.proc_handler	= proc_dointvec_minmax,
2044 		.extra1		= SYSCTL_ZERO,
2045 		.extra2		= SYSCTL_MAXOLDUID,
2046 	},
2047 #ifdef CONFIG_S390
2048 	{
2049 		.procname	= "userprocess_debug",
2050 		.data		= &show_unhandled_signals,
2051 		.maxlen		= sizeof(int),
2052 		.mode		= 0644,
2053 		.proc_handler	= proc_dointvec,
2054 	},
2055 #endif
2056 #ifdef CONFIG_SMP
2057 	{
2058 		.procname	= "oops_all_cpu_backtrace",
2059 		.data		= &sysctl_oops_all_cpu_backtrace,
2060 		.maxlen		= sizeof(int),
2061 		.mode		= 0644,
2062 		.proc_handler	= proc_dointvec_minmax,
2063 		.extra1		= SYSCTL_ZERO,
2064 		.extra2		= SYSCTL_ONE,
2065 	},
2066 #endif /* CONFIG_SMP */
2067 	{
2068 		.procname	= "pid_max",
2069 		.data		= &pid_max,
2070 		.maxlen		= sizeof (int),
2071 		.mode		= 0644,
2072 		.proc_handler	= proc_dointvec_minmax,
2073 		.extra1		= &pid_max_min,
2074 		.extra2		= &pid_max_max,
2075 	},
2076 	{
2077 		.procname	= "panic_on_oops",
2078 		.data		= &panic_on_oops,
2079 		.maxlen		= sizeof(int),
2080 		.mode		= 0644,
2081 		.proc_handler	= proc_dointvec,
2082 	},
2083 	{
2084 		.procname	= "panic_print",
2085 		.data		= &panic_print,
2086 		.maxlen		= sizeof(unsigned long),
2087 		.mode		= 0644,
2088 		.proc_handler	= proc_doulongvec_minmax,
2089 	},
2090 	{
2091 		.procname	= "ngroups_max",
2092 		.data		= (void *)&ngroups_max,
2093 		.maxlen		= sizeof (int),
2094 		.mode		= 0444,
2095 		.proc_handler	= proc_dointvec,
2096 	},
2097 	{
2098 		.procname	= "cap_last_cap",
2099 		.data		= (void *)&cap_last_cap,
2100 		.maxlen		= sizeof(int),
2101 		.mode		= 0444,
2102 		.proc_handler	= proc_dointvec,
2103 	},
2104 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
2105 	{
2106 		.procname       = "unknown_nmi_panic",
2107 		.data           = &unknown_nmi_panic,
2108 		.maxlen         = sizeof (int),
2109 		.mode           = 0644,
2110 		.proc_handler   = proc_dointvec,
2111 	},
2112 #endif
2113 
2114 #if (defined(CONFIG_X86_32) || defined(CONFIG_PARISC)) && \
2115 	defined(CONFIG_DEBUG_STACKOVERFLOW)
2116 	{
2117 		.procname	= "panic_on_stackoverflow",
2118 		.data		= &sysctl_panic_on_stackoverflow,
2119 		.maxlen		= sizeof(int),
2120 		.mode		= 0644,
2121 		.proc_handler	= proc_dointvec,
2122 	},
2123 #endif
2124 #if defined(CONFIG_X86)
2125 	{
2126 		.procname	= "panic_on_unrecovered_nmi",
2127 		.data		= &panic_on_unrecovered_nmi,
2128 		.maxlen		= sizeof(int),
2129 		.mode		= 0644,
2130 		.proc_handler	= proc_dointvec,
2131 	},
2132 	{
2133 		.procname	= "panic_on_io_nmi",
2134 		.data		= &panic_on_io_nmi,
2135 		.maxlen		= sizeof(int),
2136 		.mode		= 0644,
2137 		.proc_handler	= proc_dointvec,
2138 	},
2139 	{
2140 		.procname	= "bootloader_type",
2141 		.data		= &bootloader_type,
2142 		.maxlen		= sizeof (int),
2143 		.mode		= 0444,
2144 		.proc_handler	= proc_dointvec,
2145 	},
2146 	{
2147 		.procname	= "bootloader_version",
2148 		.data		= &bootloader_version,
2149 		.maxlen		= sizeof (int),
2150 		.mode		= 0444,
2151 		.proc_handler	= proc_dointvec,
2152 	},
2153 	{
2154 		.procname	= "io_delay_type",
2155 		.data		= &io_delay_type,
2156 		.maxlen		= sizeof(int),
2157 		.mode		= 0644,
2158 		.proc_handler	= proc_dointvec,
2159 	},
2160 #endif
2161 #if defined(CONFIG_MMU)
2162 	{
2163 		.procname	= "randomize_va_space",
2164 		.data		= &randomize_va_space,
2165 		.maxlen		= sizeof(int),
2166 		.mode		= 0644,
2167 		.proc_handler	= proc_dointvec,
2168 	},
2169 #endif
2170 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
2171 	{
2172 		.procname	= "spin_retry",
2173 		.data		= &spin_retry,
2174 		.maxlen		= sizeof (int),
2175 		.mode		= 0644,
2176 		.proc_handler	= proc_dointvec,
2177 	},
2178 #endif
2179 #if	defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
2180 	{
2181 		.procname	= "acpi_video_flags",
2182 		.data		= &acpi_realmode_flags,
2183 		.maxlen		= sizeof (unsigned long),
2184 		.mode		= 0644,
2185 		.proc_handler	= proc_doulongvec_minmax,
2186 	},
2187 #endif
2188 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
2189 	{
2190 		.procname	= "ignore-unaligned-usertrap",
2191 		.data		= &no_unaligned_warning,
2192 		.maxlen		= sizeof (int),
2193 		.mode		= 0644,
2194 		.proc_handler	= proc_dointvec,
2195 	},
2196 #endif
2197 #ifdef CONFIG_IA64
2198 	{
2199 		.procname	= "unaligned-dump-stack",
2200 		.data		= &unaligned_dump_stack,
2201 		.maxlen		= sizeof (int),
2202 		.mode		= 0644,
2203 		.proc_handler	= proc_dointvec,
2204 	},
2205 #endif
2206 #ifdef CONFIG_RT_MUTEXES
2207 	{
2208 		.procname	= "max_lock_depth",
2209 		.data		= &max_lock_depth,
2210 		.maxlen		= sizeof(int),
2211 		.mode		= 0644,
2212 		.proc_handler	= proc_dointvec,
2213 	},
2214 #endif
2215 	{
2216 		.procname	= "poweroff_cmd",
2217 		.data		= &poweroff_cmd,
2218 		.maxlen		= POWEROFF_CMD_PATH_LEN,
2219 		.mode		= 0644,
2220 		.proc_handler	= proc_dostring,
2221 	},
2222 #ifdef CONFIG_KEYS
2223 	{
2224 		.procname	= "keys",
2225 		.mode		= 0555,
2226 		.child		= key_sysctls,
2227 	},
2228 #endif
2229 #ifdef CONFIG_PERF_EVENTS
2230 	/*
2231 	 * User-space scripts rely on the existence of this file
2232 	 * as a feature check for perf_events being enabled.
2233 	 *
2234 	 * So it's an ABI, do not remove!
2235 	 */
2236 	{
2237 		.procname	= "perf_event_paranoid",
2238 		.data		= &sysctl_perf_event_paranoid,
2239 		.maxlen		= sizeof(sysctl_perf_event_paranoid),
2240 		.mode		= 0644,
2241 		.proc_handler	= proc_dointvec,
2242 	},
2243 	{
2244 		.procname	= "perf_event_mlock_kb",
2245 		.data		= &sysctl_perf_event_mlock,
2246 		.maxlen		= sizeof(sysctl_perf_event_mlock),
2247 		.mode		= 0644,
2248 		.proc_handler	= proc_dointvec,
2249 	},
2250 	{
2251 		.procname	= "perf_event_max_sample_rate",
2252 		.data		= &sysctl_perf_event_sample_rate,
2253 		.maxlen		= sizeof(sysctl_perf_event_sample_rate),
2254 		.mode		= 0644,
2255 		.proc_handler	= perf_proc_update_handler,
2256 		.extra1		= SYSCTL_ONE,
2257 	},
2258 	{
2259 		.procname	= "perf_cpu_time_max_percent",
2260 		.data		= &sysctl_perf_cpu_time_max_percent,
2261 		.maxlen		= sizeof(sysctl_perf_cpu_time_max_percent),
2262 		.mode		= 0644,
2263 		.proc_handler	= perf_cpu_time_max_percent_handler,
2264 		.extra1		= SYSCTL_ZERO,
2265 		.extra2		= SYSCTL_ONE_HUNDRED,
2266 	},
2267 	{
2268 		.procname	= "perf_event_max_stack",
2269 		.data		= &sysctl_perf_event_max_stack,
2270 		.maxlen		= sizeof(sysctl_perf_event_max_stack),
2271 		.mode		= 0644,
2272 		.proc_handler	= perf_event_max_stack_handler,
2273 		.extra1		= SYSCTL_ZERO,
2274 		.extra2		= (void *)&six_hundred_forty_kb,
2275 	},
2276 	{
2277 		.procname	= "perf_event_max_contexts_per_stack",
2278 		.data		= &sysctl_perf_event_max_contexts_per_stack,
2279 		.maxlen		= sizeof(sysctl_perf_event_max_contexts_per_stack),
2280 		.mode		= 0644,
2281 		.proc_handler	= perf_event_max_stack_handler,
2282 		.extra1		= SYSCTL_ZERO,
2283 		.extra2		= SYSCTL_ONE_THOUSAND,
2284 	},
2285 #endif
2286 	{
2287 		.procname	= "panic_on_warn",
2288 		.data		= &panic_on_warn,
2289 		.maxlen		= sizeof(int),
2290 		.mode		= 0644,
2291 		.proc_handler	= proc_dointvec_minmax,
2292 		.extra1		= SYSCTL_ZERO,
2293 		.extra2		= SYSCTL_ONE,
2294 	},
2295 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
2296 	{
2297 		.procname	= "timer_migration",
2298 		.data		= &sysctl_timer_migration,
2299 		.maxlen		= sizeof(unsigned int),
2300 		.mode		= 0644,
2301 		.proc_handler	= timer_migration_handler,
2302 		.extra1		= SYSCTL_ZERO,
2303 		.extra2		= SYSCTL_ONE,
2304 	},
2305 #endif
2306 #ifdef CONFIG_BPF_SYSCALL
2307 	{
2308 		.procname	= "unprivileged_bpf_disabled",
2309 		.data		= &sysctl_unprivileged_bpf_disabled,
2310 		.maxlen		= sizeof(sysctl_unprivileged_bpf_disabled),
2311 		.mode		= 0644,
2312 		.proc_handler	= bpf_unpriv_handler,
2313 		.extra1		= SYSCTL_ZERO,
2314 		.extra2		= SYSCTL_TWO,
2315 	},
2316 	{
2317 		.procname	= "bpf_stats_enabled",
2318 		.data		= &bpf_stats_enabled_key.key,
2319 		.maxlen		= sizeof(bpf_stats_enabled_key),
2320 		.mode		= 0644,
2321 		.proc_handler	= bpf_stats_handler,
2322 	},
2323 #endif
2324 #if defined(CONFIG_TREE_RCU)
2325 	{
2326 		.procname	= "panic_on_rcu_stall",
2327 		.data		= &sysctl_panic_on_rcu_stall,
2328 		.maxlen		= sizeof(sysctl_panic_on_rcu_stall),
2329 		.mode		= 0644,
2330 		.proc_handler	= proc_dointvec_minmax,
2331 		.extra1		= SYSCTL_ZERO,
2332 		.extra2		= SYSCTL_ONE,
2333 	},
2334 #endif
2335 #if defined(CONFIG_TREE_RCU)
2336 	{
2337 		.procname	= "max_rcu_stall_to_panic",
2338 		.data		= &sysctl_max_rcu_stall_to_panic,
2339 		.maxlen		= sizeof(sysctl_max_rcu_stall_to_panic),
2340 		.mode		= 0644,
2341 		.proc_handler	= proc_dointvec_minmax,
2342 		.extra1		= SYSCTL_ONE,
2343 		.extra2		= SYSCTL_INT_MAX,
2344 	},
2345 #endif
2346 	{ }
2347 };
2348 
2349 static struct ctl_table vm_table[] = {
2350 	{
2351 		.procname	= "overcommit_memory",
2352 		.data		= &sysctl_overcommit_memory,
2353 		.maxlen		= sizeof(sysctl_overcommit_memory),
2354 		.mode		= 0644,
2355 		.proc_handler	= overcommit_policy_handler,
2356 		.extra1		= SYSCTL_ZERO,
2357 		.extra2		= SYSCTL_TWO,
2358 	},
2359 	{
2360 		.procname	= "panic_on_oom",
2361 		.data		= &sysctl_panic_on_oom,
2362 		.maxlen		= sizeof(sysctl_panic_on_oom),
2363 		.mode		= 0644,
2364 		.proc_handler	= proc_dointvec_minmax,
2365 		.extra1		= SYSCTL_ZERO,
2366 		.extra2		= SYSCTL_TWO,
2367 	},
2368 	{
2369 		.procname	= "oom_kill_allocating_task",
2370 		.data		= &sysctl_oom_kill_allocating_task,
2371 		.maxlen		= sizeof(sysctl_oom_kill_allocating_task),
2372 		.mode		= 0644,
2373 		.proc_handler	= proc_dointvec,
2374 	},
2375 	{
2376 		.procname	= "oom_dump_tasks",
2377 		.data		= &sysctl_oom_dump_tasks,
2378 		.maxlen		= sizeof(sysctl_oom_dump_tasks),
2379 		.mode		= 0644,
2380 		.proc_handler	= proc_dointvec,
2381 	},
2382 	{
2383 		.procname	= "overcommit_ratio",
2384 		.data		= &sysctl_overcommit_ratio,
2385 		.maxlen		= sizeof(sysctl_overcommit_ratio),
2386 		.mode		= 0644,
2387 		.proc_handler	= overcommit_ratio_handler,
2388 	},
2389 	{
2390 		.procname	= "overcommit_kbytes",
2391 		.data		= &sysctl_overcommit_kbytes,
2392 		.maxlen		= sizeof(sysctl_overcommit_kbytes),
2393 		.mode		= 0644,
2394 		.proc_handler	= overcommit_kbytes_handler,
2395 	},
2396 	{
2397 		.procname	= "page-cluster",
2398 		.data		= &page_cluster,
2399 		.maxlen		= sizeof(int),
2400 		.mode		= 0644,
2401 		.proc_handler	= proc_dointvec_minmax,
2402 		.extra1		= SYSCTL_ZERO,
2403 	},
2404 	{
2405 		.procname	= "dirty_background_ratio",
2406 		.data		= &dirty_background_ratio,
2407 		.maxlen		= sizeof(dirty_background_ratio),
2408 		.mode		= 0644,
2409 		.proc_handler	= dirty_background_ratio_handler,
2410 		.extra1		= SYSCTL_ZERO,
2411 		.extra2		= SYSCTL_ONE_HUNDRED,
2412 	},
2413 	{
2414 		.procname	= "dirty_background_bytes",
2415 		.data		= &dirty_background_bytes,
2416 		.maxlen		= sizeof(dirty_background_bytes),
2417 		.mode		= 0644,
2418 		.proc_handler	= dirty_background_bytes_handler,
2419 		.extra1		= SYSCTL_LONG_ONE,
2420 	},
2421 	{
2422 		.procname	= "dirty_ratio",
2423 		.data		= &vm_dirty_ratio,
2424 		.maxlen		= sizeof(vm_dirty_ratio),
2425 		.mode		= 0644,
2426 		.proc_handler	= dirty_ratio_handler,
2427 		.extra1		= SYSCTL_ZERO,
2428 		.extra2		= SYSCTL_ONE_HUNDRED,
2429 	},
2430 	{
2431 		.procname	= "dirty_bytes",
2432 		.data		= &vm_dirty_bytes,
2433 		.maxlen		= sizeof(vm_dirty_bytes),
2434 		.mode		= 0644,
2435 		.proc_handler	= dirty_bytes_handler,
2436 		.extra1		= (void *)&dirty_bytes_min,
2437 	},
2438 	{
2439 		.procname	= "dirty_writeback_centisecs",
2440 		.data		= &dirty_writeback_interval,
2441 		.maxlen		= sizeof(dirty_writeback_interval),
2442 		.mode		= 0644,
2443 		.proc_handler	= dirty_writeback_centisecs_handler,
2444 	},
2445 	{
2446 		.procname	= "dirty_expire_centisecs",
2447 		.data		= &dirty_expire_interval,
2448 		.maxlen		= sizeof(dirty_expire_interval),
2449 		.mode		= 0644,
2450 		.proc_handler	= proc_dointvec_minmax,
2451 		.extra1		= SYSCTL_ZERO,
2452 	},
2453 	{
2454 		.procname	= "dirtytime_expire_seconds",
2455 		.data		= &dirtytime_expire_interval,
2456 		.maxlen		= sizeof(dirtytime_expire_interval),
2457 		.mode		= 0644,
2458 		.proc_handler	= dirtytime_interval_handler,
2459 		.extra1		= SYSCTL_ZERO,
2460 	},
2461 	{
2462 		.procname	= "swappiness",
2463 		.data		= &vm_swappiness,
2464 		.maxlen		= sizeof(vm_swappiness),
2465 		.mode		= 0644,
2466 		.proc_handler	= proc_dointvec_minmax,
2467 		.extra1		= SYSCTL_ZERO,
2468 		.extra2		= SYSCTL_TWO_HUNDRED,
2469 	},
2470 #ifdef CONFIG_HUGETLB_PAGE
2471 	{
2472 		.procname	= "nr_hugepages",
2473 		.data		= NULL,
2474 		.maxlen		= sizeof(unsigned long),
2475 		.mode		= 0644,
2476 		.proc_handler	= hugetlb_sysctl_handler,
2477 	},
2478 #ifdef CONFIG_NUMA
2479 	{
2480 		.procname       = "nr_hugepages_mempolicy",
2481 		.data           = NULL,
2482 		.maxlen         = sizeof(unsigned long),
2483 		.mode           = 0644,
2484 		.proc_handler   = &hugetlb_mempolicy_sysctl_handler,
2485 	},
2486 	{
2487 		.procname		= "numa_stat",
2488 		.data			= &sysctl_vm_numa_stat,
2489 		.maxlen			= sizeof(int),
2490 		.mode			= 0644,
2491 		.proc_handler	= sysctl_vm_numa_stat_handler,
2492 		.extra1			= SYSCTL_ZERO,
2493 		.extra2			= SYSCTL_ONE,
2494 	},
2495 #endif
2496 	 {
2497 		.procname	= "hugetlb_shm_group",
2498 		.data		= &sysctl_hugetlb_shm_group,
2499 		.maxlen		= sizeof(gid_t),
2500 		.mode		= 0644,
2501 		.proc_handler	= proc_dointvec,
2502 	 },
2503 	{
2504 		.procname	= "nr_overcommit_hugepages",
2505 		.data		= NULL,
2506 		.maxlen		= sizeof(unsigned long),
2507 		.mode		= 0644,
2508 		.proc_handler	= hugetlb_overcommit_handler,
2509 	},
2510 #endif
2511 	{
2512 		.procname	= "lowmem_reserve_ratio",
2513 		.data		= &sysctl_lowmem_reserve_ratio,
2514 		.maxlen		= sizeof(sysctl_lowmem_reserve_ratio),
2515 		.mode		= 0644,
2516 		.proc_handler	= lowmem_reserve_ratio_sysctl_handler,
2517 	},
2518 	{
2519 		.procname	= "drop_caches",
2520 		.data		= &sysctl_drop_caches,
2521 		.maxlen		= sizeof(int),
2522 		.mode		= 0200,
2523 		.proc_handler	= drop_caches_sysctl_handler,
2524 		.extra1		= SYSCTL_ONE,
2525 		.extra2		= SYSCTL_FOUR,
2526 	},
2527 #ifdef CONFIG_COMPACTION
2528 	{
2529 		.procname	= "compact_memory",
2530 		.data		= NULL,
2531 		.maxlen		= sizeof(int),
2532 		.mode		= 0200,
2533 		.proc_handler	= sysctl_compaction_handler,
2534 	},
2535 	{
2536 		.procname	= "compaction_proactiveness",
2537 		.data		= &sysctl_compaction_proactiveness,
2538 		.maxlen		= sizeof(sysctl_compaction_proactiveness),
2539 		.mode		= 0644,
2540 		.proc_handler	= compaction_proactiveness_sysctl_handler,
2541 		.extra1		= SYSCTL_ZERO,
2542 		.extra2		= SYSCTL_ONE_HUNDRED,
2543 	},
2544 	{
2545 		.procname	= "extfrag_threshold",
2546 		.data		= &sysctl_extfrag_threshold,
2547 		.maxlen		= sizeof(int),
2548 		.mode		= 0644,
2549 		.proc_handler	= proc_dointvec_minmax,
2550 		.extra1		= SYSCTL_ZERO,
2551 		.extra2		= (void *)&max_extfrag_threshold,
2552 	},
2553 	{
2554 		.procname	= "compact_unevictable_allowed",
2555 		.data		= &sysctl_compact_unevictable_allowed,
2556 		.maxlen		= sizeof(int),
2557 		.mode		= 0644,
2558 		.proc_handler	= proc_dointvec_minmax_warn_RT_change,
2559 		.extra1		= SYSCTL_ZERO,
2560 		.extra2		= SYSCTL_ONE,
2561 	},
2562 
2563 #endif /* CONFIG_COMPACTION */
2564 	{
2565 		.procname	= "min_free_kbytes",
2566 		.data		= &min_free_kbytes,
2567 		.maxlen		= sizeof(min_free_kbytes),
2568 		.mode		= 0644,
2569 		.proc_handler	= min_free_kbytes_sysctl_handler,
2570 		.extra1		= SYSCTL_ZERO,
2571 	},
2572 	{
2573 		.procname	= "watermark_boost_factor",
2574 		.data		= &watermark_boost_factor,
2575 		.maxlen		= sizeof(watermark_boost_factor),
2576 		.mode		= 0644,
2577 		.proc_handler	= proc_dointvec_minmax,
2578 		.extra1		= SYSCTL_ZERO,
2579 	},
2580 	{
2581 		.procname	= "watermark_scale_factor",
2582 		.data		= &watermark_scale_factor,
2583 		.maxlen		= sizeof(watermark_scale_factor),
2584 		.mode		= 0644,
2585 		.proc_handler	= watermark_scale_factor_sysctl_handler,
2586 		.extra1		= SYSCTL_ONE,
2587 		.extra2		= SYSCTL_THREE_THOUSAND,
2588 	},
2589 	{
2590 		.procname	= "percpu_pagelist_high_fraction",
2591 		.data		= &percpu_pagelist_high_fraction,
2592 		.maxlen		= sizeof(percpu_pagelist_high_fraction),
2593 		.mode		= 0644,
2594 		.proc_handler	= percpu_pagelist_high_fraction_sysctl_handler,
2595 		.extra1		= SYSCTL_ZERO,
2596 	},
2597 	{
2598 		.procname	= "page_lock_unfairness",
2599 		.data		= &sysctl_page_lock_unfairness,
2600 		.maxlen		= sizeof(sysctl_page_lock_unfairness),
2601 		.mode		= 0644,
2602 		.proc_handler	= proc_dointvec_minmax,
2603 		.extra1		= SYSCTL_ZERO,
2604 	},
2605 #ifdef CONFIG_MMU
2606 	{
2607 		.procname	= "max_map_count",
2608 		.data		= &sysctl_max_map_count,
2609 		.maxlen		= sizeof(sysctl_max_map_count),
2610 		.mode		= 0644,
2611 		.proc_handler	= proc_dointvec_minmax,
2612 		.extra1		= SYSCTL_ZERO,
2613 	},
2614 #else
2615 	{
2616 		.procname	= "nr_trim_pages",
2617 		.data		= &sysctl_nr_trim_pages,
2618 		.maxlen		= sizeof(sysctl_nr_trim_pages),
2619 		.mode		= 0644,
2620 		.proc_handler	= proc_dointvec_minmax,
2621 		.extra1		= SYSCTL_ZERO,
2622 	},
2623 #endif
2624 	{
2625 		.procname	= "laptop_mode",
2626 		.data		= &laptop_mode,
2627 		.maxlen		= sizeof(laptop_mode),
2628 		.mode		= 0644,
2629 		.proc_handler	= proc_dointvec_jiffies,
2630 	},
2631 	{
2632 		.procname	= "vfs_cache_pressure",
2633 		.data		= &sysctl_vfs_cache_pressure,
2634 		.maxlen		= sizeof(sysctl_vfs_cache_pressure),
2635 		.mode		= 0644,
2636 		.proc_handler	= proc_dointvec_minmax,
2637 		.extra1		= SYSCTL_ZERO,
2638 	},
2639 #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
2640     defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
2641 	{
2642 		.procname	= "legacy_va_layout",
2643 		.data		= &sysctl_legacy_va_layout,
2644 		.maxlen		= sizeof(sysctl_legacy_va_layout),
2645 		.mode		= 0644,
2646 		.proc_handler	= proc_dointvec_minmax,
2647 		.extra1		= SYSCTL_ZERO,
2648 	},
2649 #endif
2650 #ifdef CONFIG_NUMA
2651 	{
2652 		.procname	= "zone_reclaim_mode",
2653 		.data		= &node_reclaim_mode,
2654 		.maxlen		= sizeof(node_reclaim_mode),
2655 		.mode		= 0644,
2656 		.proc_handler	= proc_dointvec_minmax,
2657 		.extra1		= SYSCTL_ZERO,
2658 	},
2659 	{
2660 		.procname	= "min_unmapped_ratio",
2661 		.data		= &sysctl_min_unmapped_ratio,
2662 		.maxlen		= sizeof(sysctl_min_unmapped_ratio),
2663 		.mode		= 0644,
2664 		.proc_handler	= sysctl_min_unmapped_ratio_sysctl_handler,
2665 		.extra1		= SYSCTL_ZERO,
2666 		.extra2		= SYSCTL_ONE_HUNDRED,
2667 	},
2668 	{
2669 		.procname	= "min_slab_ratio",
2670 		.data		= &sysctl_min_slab_ratio,
2671 		.maxlen		= sizeof(sysctl_min_slab_ratio),
2672 		.mode		= 0644,
2673 		.proc_handler	= sysctl_min_slab_ratio_sysctl_handler,
2674 		.extra1		= SYSCTL_ZERO,
2675 		.extra2		= SYSCTL_ONE_HUNDRED,
2676 	},
2677 #endif
2678 #ifdef CONFIG_SMP
2679 	{
2680 		.procname	= "stat_interval",
2681 		.data		= &sysctl_stat_interval,
2682 		.maxlen		= sizeof(sysctl_stat_interval),
2683 		.mode		= 0644,
2684 		.proc_handler	= proc_dointvec_jiffies,
2685 	},
2686 	{
2687 		.procname	= "stat_refresh",
2688 		.data		= NULL,
2689 		.maxlen		= 0,
2690 		.mode		= 0600,
2691 		.proc_handler	= vmstat_refresh,
2692 	},
2693 #endif
2694 #ifdef CONFIG_MMU
2695 	{
2696 		.procname	= "mmap_min_addr",
2697 		.data		= &dac_mmap_min_addr,
2698 		.maxlen		= sizeof(unsigned long),
2699 		.mode		= 0644,
2700 		.proc_handler	= mmap_min_addr_handler,
2701 	},
2702 #endif
2703 #ifdef CONFIG_NUMA
2704 	{
2705 		.procname	= "numa_zonelist_order",
2706 		.data		= &numa_zonelist_order,
2707 		.maxlen		= NUMA_ZONELIST_ORDER_LEN,
2708 		.mode		= 0644,
2709 		.proc_handler	= numa_zonelist_order_handler,
2710 	},
2711 #endif
2712 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
2713    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
2714 	{
2715 		.procname	= "vdso_enabled",
2716 #ifdef CONFIG_X86_32
2717 		.data		= &vdso32_enabled,
2718 		.maxlen		= sizeof(vdso32_enabled),
2719 #else
2720 		.data		= &vdso_enabled,
2721 		.maxlen		= sizeof(vdso_enabled),
2722 #endif
2723 		.mode		= 0644,
2724 		.proc_handler	= proc_dointvec,
2725 		.extra1		= SYSCTL_ZERO,
2726 	},
2727 #endif
2728 #ifdef CONFIG_HIGHMEM
2729 	{
2730 		.procname	= "highmem_is_dirtyable",
2731 		.data		= &vm_highmem_is_dirtyable,
2732 		.maxlen		= sizeof(vm_highmem_is_dirtyable),
2733 		.mode		= 0644,
2734 		.proc_handler	= proc_dointvec_minmax,
2735 		.extra1		= SYSCTL_ZERO,
2736 		.extra2		= SYSCTL_ONE,
2737 	},
2738 #endif
2739 #ifdef CONFIG_MEMORY_FAILURE
2740 	{
2741 		.procname	= "memory_failure_early_kill",
2742 		.data		= &sysctl_memory_failure_early_kill,
2743 		.maxlen		= sizeof(sysctl_memory_failure_early_kill),
2744 		.mode		= 0644,
2745 		.proc_handler	= proc_dointvec_minmax,
2746 		.extra1		= SYSCTL_ZERO,
2747 		.extra2		= SYSCTL_ONE,
2748 	},
2749 	{
2750 		.procname	= "memory_failure_recovery",
2751 		.data		= &sysctl_memory_failure_recovery,
2752 		.maxlen		= sizeof(sysctl_memory_failure_recovery),
2753 		.mode		= 0644,
2754 		.proc_handler	= proc_dointvec_minmax,
2755 		.extra1		= SYSCTL_ZERO,
2756 		.extra2		= SYSCTL_ONE,
2757 	},
2758 #endif
2759 	{
2760 		.procname	= "user_reserve_kbytes",
2761 		.data		= &sysctl_user_reserve_kbytes,
2762 		.maxlen		= sizeof(sysctl_user_reserve_kbytes),
2763 		.mode		= 0644,
2764 		.proc_handler	= proc_doulongvec_minmax,
2765 	},
2766 	{
2767 		.procname	= "admin_reserve_kbytes",
2768 		.data		= &sysctl_admin_reserve_kbytes,
2769 		.maxlen		= sizeof(sysctl_admin_reserve_kbytes),
2770 		.mode		= 0644,
2771 		.proc_handler	= proc_doulongvec_minmax,
2772 	},
2773 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
2774 	{
2775 		.procname	= "mmap_rnd_bits",
2776 		.data		= &mmap_rnd_bits,
2777 		.maxlen		= sizeof(mmap_rnd_bits),
2778 		.mode		= 0600,
2779 		.proc_handler	= proc_dointvec_minmax,
2780 		.extra1		= (void *)&mmap_rnd_bits_min,
2781 		.extra2		= (void *)&mmap_rnd_bits_max,
2782 	},
2783 #endif
2784 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
2785 	{
2786 		.procname	= "mmap_rnd_compat_bits",
2787 		.data		= &mmap_rnd_compat_bits,
2788 		.maxlen		= sizeof(mmap_rnd_compat_bits),
2789 		.mode		= 0600,
2790 		.proc_handler	= proc_dointvec_minmax,
2791 		.extra1		= (void *)&mmap_rnd_compat_bits_min,
2792 		.extra2		= (void *)&mmap_rnd_compat_bits_max,
2793 	},
2794 #endif
2795 #ifdef CONFIG_USERFAULTFD
2796 	{
2797 		.procname	= "unprivileged_userfaultfd",
2798 		.data		= &sysctl_unprivileged_userfaultfd,
2799 		.maxlen		= sizeof(sysctl_unprivileged_userfaultfd),
2800 		.mode		= 0644,
2801 		.proc_handler	= proc_dointvec_minmax,
2802 		.extra1		= SYSCTL_ZERO,
2803 		.extra2		= SYSCTL_ONE,
2804 	},
2805 #endif
2806 	{ }
2807 };
2808 
2809 static struct ctl_table debug_table[] = {
2810 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
2811 	{
2812 		.procname	= "exception-trace",
2813 		.data		= &show_unhandled_signals,
2814 		.maxlen		= sizeof(int),
2815 		.mode		= 0644,
2816 		.proc_handler	= proc_dointvec
2817 	},
2818 #endif
2819 	{ }
2820 };
2821 
2822 static struct ctl_table dev_table[] = {
2823 	{ }
2824 };
2825 
2826 DECLARE_SYSCTL_BASE(kernel, kern_table);
2827 DECLARE_SYSCTL_BASE(vm, vm_table);
2828 DECLARE_SYSCTL_BASE(debug, debug_table);
2829 DECLARE_SYSCTL_BASE(dev, dev_table);
2830 
2831 int __init sysctl_init_bases(void)
2832 {
2833 	register_sysctl_base(kernel);
2834 	register_sysctl_base(vm);
2835 	register_sysctl_base(debug);
2836 	register_sysctl_base(dev);
2837 
2838 	return 0;
2839 }
2840 #endif /* CONFIG_SYSCTL */
2841 /*
2842  * No sense putting this after each symbol definition, twice,
2843  * exception granted :-)
2844  */
2845 EXPORT_SYMBOL(proc_dobool);
2846 EXPORT_SYMBOL(proc_dointvec);
2847 EXPORT_SYMBOL(proc_douintvec);
2848 EXPORT_SYMBOL(proc_dointvec_jiffies);
2849 EXPORT_SYMBOL(proc_dointvec_minmax);
2850 EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
2851 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2852 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2853 EXPORT_SYMBOL(proc_dostring);
2854 EXPORT_SYMBOL(proc_doulongvec_minmax);
2855 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2856 EXPORT_SYMBOL(proc_do_large_bitmap);
2857