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/mount.h>
65 #include <linux/userfaultfd_k.h>
66 #include <linux/pid.h>
67
68 #include "../lib/kstrtox.h"
69
70 #include <linux/uaccess.h>
71 #include <asm/processor.h>
72
73 #ifdef CONFIG_X86
74 #include <asm/nmi.h>
75 #include <asm/stacktrace.h>
76 #include <asm/io.h>
77 #endif
78 #ifdef CONFIG_SPARC
79 #include <asm/setup.h>
80 #endif
81 #ifdef CONFIG_RT_MUTEXES
82 #include <linux/rtmutex.h>
83 #endif
84
85 /* shared constants to be used in various sysctls */
86 const int sysctl_vals[] = { 0, 1, 2, 3, 4, 100, 200, 1000, 3000, INT_MAX, 65535, -1 };
87 EXPORT_SYMBOL(sysctl_vals);
88
89 const unsigned long sysctl_long_vals[] = { 0, 1, LONG_MAX };
90 EXPORT_SYMBOL_GPL(sysctl_long_vals);
91
92 #if defined(CONFIG_SYSCTL)
93
94 /* Constants used for minimum and maximum */
95
96 #ifdef CONFIG_PERF_EVENTS
97 static const int six_hundred_forty_kb = 640 * 1024;
98 #endif
99
100
101 static const int ngroups_max = NGROUPS_MAX;
102 static const int cap_last_cap = CAP_LAST_CAP;
103
104 #ifdef CONFIG_PROC_SYSCTL
105
106 /**
107 * enum sysctl_writes_mode - supported sysctl write modes
108 *
109 * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
110 * to be written, and multiple writes on the same sysctl file descriptor
111 * will rewrite the sysctl value, regardless of file position. No warning
112 * is issued when the initial position is not 0.
113 * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
114 * not 0.
115 * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
116 * file position 0 and the value must be fully contained in the buffer
117 * sent to the write syscall. If dealing with strings respect the file
118 * position, but restrict this to the max length of the buffer, anything
119 * passed the max length will be ignored. Multiple writes will append
120 * to the buffer.
121 *
122 * These write modes control how current file position affects the behavior of
123 * updating sysctl values through the proc interface on each write.
124 */
125 enum sysctl_writes_mode {
126 SYSCTL_WRITES_LEGACY = -1,
127 SYSCTL_WRITES_WARN = 0,
128 SYSCTL_WRITES_STRICT = 1,
129 };
130
131 static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
132 #endif /* CONFIG_PROC_SYSCTL */
133
134 #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
135 defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
136 int sysctl_legacy_va_layout;
137 #endif
138
139 #endif /* CONFIG_SYSCTL */
140
141 /*
142 * /proc/sys support
143 */
144
145 #ifdef CONFIG_PROC_SYSCTL
146
_proc_do_string(char * data,int maxlen,int write,char * buffer,size_t * lenp,loff_t * ppos)147 static int _proc_do_string(char *data, int maxlen, int write,
148 char *buffer, size_t *lenp, loff_t *ppos)
149 {
150 size_t len;
151 char c, *p;
152
153 if (!data || !maxlen || !*lenp) {
154 *lenp = 0;
155 return 0;
156 }
157
158 if (write) {
159 if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
160 /* Only continue writes not past the end of buffer. */
161 len = strlen(data);
162 if (len > maxlen - 1)
163 len = maxlen - 1;
164
165 if (*ppos > len)
166 return 0;
167 len = *ppos;
168 } else {
169 /* Start writing from beginning of buffer. */
170 len = 0;
171 }
172
173 *ppos += *lenp;
174 p = buffer;
175 while ((p - buffer) < *lenp && len < maxlen - 1) {
176 c = *(p++);
177 if (c == 0 || c == '\n')
178 break;
179 data[len++] = c;
180 }
181 data[len] = 0;
182 } else {
183 len = strlen(data);
184 if (len > maxlen)
185 len = maxlen;
186
187 if (*ppos > len) {
188 *lenp = 0;
189 return 0;
190 }
191
192 data += *ppos;
193 len -= *ppos;
194
195 if (len > *lenp)
196 len = *lenp;
197 if (len)
198 memcpy(buffer, data, len);
199 if (len < *lenp) {
200 buffer[len] = '\n';
201 len++;
202 }
203 *lenp = len;
204 *ppos += len;
205 }
206 return 0;
207 }
208
warn_sysctl_write(struct ctl_table * table)209 static void warn_sysctl_write(struct ctl_table *table)
210 {
211 pr_warn_once("%s wrote to %s when file position was not 0!\n"
212 "This will not be supported in the future. To silence this\n"
213 "warning, set kernel.sysctl_writes_strict = -1\n",
214 current->comm, table->procname);
215 }
216
217 /**
218 * proc_first_pos_non_zero_ignore - check if first position is allowed
219 * @ppos: file position
220 * @table: the sysctl table
221 *
222 * Returns true if the first position is non-zero and the sysctl_writes_strict
223 * mode indicates this is not allowed for numeric input types. String proc
224 * handlers can ignore the return value.
225 */
proc_first_pos_non_zero_ignore(loff_t * ppos,struct ctl_table * table)226 static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
227 struct ctl_table *table)
228 {
229 if (!*ppos)
230 return false;
231
232 switch (sysctl_writes_strict) {
233 case SYSCTL_WRITES_STRICT:
234 return true;
235 case SYSCTL_WRITES_WARN:
236 warn_sysctl_write(table);
237 return false;
238 default:
239 return false;
240 }
241 }
242
243 /**
244 * proc_dostring - read a string sysctl
245 * @table: the sysctl table
246 * @write: %TRUE if this is a write to the sysctl file
247 * @buffer: the user buffer
248 * @lenp: the size of the user buffer
249 * @ppos: file position
250 *
251 * Reads/writes a string from/to the user buffer. If the kernel
252 * buffer provided is not large enough to hold the string, the
253 * string is truncated. The copied string is %NULL-terminated.
254 * If the string is being read by the user process, it is copied
255 * and a newline '\n' is added. It is truncated if the buffer is
256 * not large enough.
257 *
258 * Returns 0 on success.
259 */
proc_dostring(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)260 int proc_dostring(struct ctl_table *table, int write,
261 void *buffer, size_t *lenp, loff_t *ppos)
262 {
263 if (write)
264 proc_first_pos_non_zero_ignore(ppos, table);
265
266 return _proc_do_string(table->data, table->maxlen, write, buffer, lenp,
267 ppos);
268 }
269
proc_skip_spaces(char ** buf,size_t * size)270 static void proc_skip_spaces(char **buf, size_t *size)
271 {
272 while (*size) {
273 if (!isspace(**buf))
274 break;
275 (*size)--;
276 (*buf)++;
277 }
278 }
279
proc_skip_char(char ** buf,size_t * size,const char v)280 static void proc_skip_char(char **buf, size_t *size, const char v)
281 {
282 while (*size) {
283 if (**buf != v)
284 break;
285 (*size)--;
286 (*buf)++;
287 }
288 }
289
290 /**
291 * strtoul_lenient - parse an ASCII formatted integer from a buffer and only
292 * fail on overflow
293 *
294 * @cp: kernel buffer containing the string to parse
295 * @endp: pointer to store the trailing characters
296 * @base: the base to use
297 * @res: where the parsed integer will be stored
298 *
299 * In case of success 0 is returned and @res will contain the parsed integer,
300 * @endp will hold any trailing characters.
301 * This function will fail the parse on overflow. If there wasn't an overflow
302 * the function will defer the decision what characters count as invalid to the
303 * caller.
304 */
strtoul_lenient(const char * cp,char ** endp,unsigned int base,unsigned long * res)305 static int strtoul_lenient(const char *cp, char **endp, unsigned int base,
306 unsigned long *res)
307 {
308 unsigned long long result;
309 unsigned int rv;
310
311 cp = _parse_integer_fixup_radix(cp, &base);
312 rv = _parse_integer(cp, base, &result);
313 if ((rv & KSTRTOX_OVERFLOW) || (result != (unsigned long)result))
314 return -ERANGE;
315
316 cp += rv;
317
318 if (endp)
319 *endp = (char *)cp;
320
321 *res = (unsigned long)result;
322 return 0;
323 }
324
325 #define TMPBUFLEN 22
326 /**
327 * proc_get_long - reads an ASCII formatted integer from a user buffer
328 *
329 * @buf: a kernel buffer
330 * @size: size of the kernel buffer
331 * @val: this is where the number will be stored
332 * @neg: set to %TRUE if number is negative
333 * @perm_tr: a vector which contains the allowed trailers
334 * @perm_tr_len: size of the perm_tr vector
335 * @tr: pointer to store the trailer character
336 *
337 * In case of success %0 is returned and @buf and @size are updated with
338 * the amount of bytes read. If @tr is non-NULL and a trailing
339 * character exists (size is non-zero after returning from this
340 * function), @tr is updated with the trailing character.
341 */
proc_get_long(char ** buf,size_t * size,unsigned long * val,bool * neg,const char * perm_tr,unsigned perm_tr_len,char * tr)342 static int proc_get_long(char **buf, size_t *size,
343 unsigned long *val, bool *neg,
344 const char *perm_tr, unsigned perm_tr_len, char *tr)
345 {
346 char *p, tmp[TMPBUFLEN];
347 ssize_t len = *size;
348
349 if (len <= 0)
350 return -EINVAL;
351
352 if (len > TMPBUFLEN - 1)
353 len = TMPBUFLEN - 1;
354
355 memcpy(tmp, *buf, len);
356
357 tmp[len] = 0;
358 p = tmp;
359 if (*p == '-' && *size > 1) {
360 *neg = true;
361 p++;
362 } else
363 *neg = false;
364 if (!isdigit(*p))
365 return -EINVAL;
366
367 if (strtoul_lenient(p, &p, 0, val))
368 return -EINVAL;
369
370 len = p - tmp;
371
372 /* We don't know if the next char is whitespace thus we may accept
373 * invalid integers (e.g. 1234...a) or two integers instead of one
374 * (e.g. 123...1). So lets not allow such large numbers. */
375 if (len == TMPBUFLEN - 1)
376 return -EINVAL;
377
378 if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
379 return -EINVAL;
380
381 if (tr && (len < *size))
382 *tr = *p;
383
384 *buf += len;
385 *size -= len;
386
387 return 0;
388 }
389
390 /**
391 * proc_put_long - converts an integer to a decimal ASCII formatted string
392 *
393 * @buf: the user buffer
394 * @size: the size of the user buffer
395 * @val: the integer to be converted
396 * @neg: sign of the number, %TRUE for negative
397 *
398 * In case of success @buf and @size are updated with the amount of bytes
399 * written.
400 */
proc_put_long(void ** buf,size_t * size,unsigned long val,bool neg)401 static void proc_put_long(void **buf, size_t *size, unsigned long val, bool neg)
402 {
403 int len;
404 char tmp[TMPBUFLEN], *p = tmp;
405
406 sprintf(p, "%s%lu", neg ? "-" : "", val);
407 len = strlen(tmp);
408 if (len > *size)
409 len = *size;
410 memcpy(*buf, tmp, len);
411 *size -= len;
412 *buf += len;
413 }
414 #undef TMPBUFLEN
415
proc_put_char(void ** buf,size_t * size,char c)416 static void proc_put_char(void **buf, size_t *size, char c)
417 {
418 if (*size) {
419 char **buffer = (char **)buf;
420 **buffer = c;
421
422 (*size)--;
423 (*buffer)++;
424 *buf = *buffer;
425 }
426 }
427
do_proc_dobool_conv(bool * negp,unsigned long * lvalp,int * valp,int write,void * data)428 static int do_proc_dobool_conv(bool *negp, unsigned long *lvalp,
429 int *valp,
430 int write, void *data)
431 {
432 if (write) {
433 *(bool *)valp = *lvalp;
434 } else {
435 int val = *(bool *)valp;
436
437 *lvalp = (unsigned long)val;
438 *negp = false;
439 }
440 return 0;
441 }
442
do_proc_dointvec_conv(bool * negp,unsigned long * lvalp,int * valp,int write,void * data)443 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
444 int *valp,
445 int write, void *data)
446 {
447 if (write) {
448 if (*negp) {
449 if (*lvalp > (unsigned long) INT_MAX + 1)
450 return -EINVAL;
451 WRITE_ONCE(*valp, -*lvalp);
452 } else {
453 if (*lvalp > (unsigned long) INT_MAX)
454 return -EINVAL;
455 WRITE_ONCE(*valp, *lvalp);
456 }
457 } else {
458 int val = READ_ONCE(*valp);
459 if (val < 0) {
460 *negp = true;
461 *lvalp = -(unsigned long)val;
462 } else {
463 *negp = false;
464 *lvalp = (unsigned long)val;
465 }
466 }
467 return 0;
468 }
469
do_proc_douintvec_conv(unsigned long * lvalp,unsigned int * valp,int write,void * data)470 static int do_proc_douintvec_conv(unsigned long *lvalp,
471 unsigned int *valp,
472 int write, void *data)
473 {
474 if (write) {
475 if (*lvalp > UINT_MAX)
476 return -EINVAL;
477 WRITE_ONCE(*valp, *lvalp);
478 } else {
479 unsigned int val = READ_ONCE(*valp);
480 *lvalp = (unsigned long)val;
481 }
482 return 0;
483 }
484
485 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
486
__do_proc_dointvec(void * tbl_data,struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos,int (* conv)(bool * negp,unsigned long * lvalp,int * valp,int write,void * data),void * data)487 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
488 int write, void *buffer,
489 size_t *lenp, loff_t *ppos,
490 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
491 int write, void *data),
492 void *data)
493 {
494 int *i, vleft, first = 1, err = 0;
495 size_t left;
496 char *p;
497
498 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
499 *lenp = 0;
500 return 0;
501 }
502
503 i = (int *) tbl_data;
504 vleft = table->maxlen / sizeof(*i);
505 left = *lenp;
506
507 if (!conv)
508 conv = do_proc_dointvec_conv;
509
510 if (write) {
511 if (proc_first_pos_non_zero_ignore(ppos, table))
512 goto out;
513
514 if (left > PAGE_SIZE - 1)
515 left = PAGE_SIZE - 1;
516 p = buffer;
517 }
518
519 for (; left && vleft--; i++, first=0) {
520 unsigned long lval;
521 bool neg;
522
523 if (write) {
524 proc_skip_spaces(&p, &left);
525
526 if (!left)
527 break;
528 err = proc_get_long(&p, &left, &lval, &neg,
529 proc_wspace_sep,
530 sizeof(proc_wspace_sep), NULL);
531 if (err)
532 break;
533 if (conv(&neg, &lval, i, 1, data)) {
534 err = -EINVAL;
535 break;
536 }
537 } else {
538 if (conv(&neg, &lval, i, 0, data)) {
539 err = -EINVAL;
540 break;
541 }
542 if (!first)
543 proc_put_char(&buffer, &left, '\t');
544 proc_put_long(&buffer, &left, lval, neg);
545 }
546 }
547
548 if (!write && !first && left && !err)
549 proc_put_char(&buffer, &left, '\n');
550 if (write && !err && left)
551 proc_skip_spaces(&p, &left);
552 if (write && first)
553 return err ? : -EINVAL;
554 *lenp -= left;
555 out:
556 *ppos += *lenp;
557 return err;
558 }
559
do_proc_dointvec(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos,int (* conv)(bool * negp,unsigned long * lvalp,int * valp,int write,void * data),void * data)560 static int do_proc_dointvec(struct ctl_table *table, int write,
561 void *buffer, size_t *lenp, loff_t *ppos,
562 int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
563 int write, void *data),
564 void *data)
565 {
566 return __do_proc_dointvec(table->data, table, write,
567 buffer, lenp, ppos, conv, data);
568 }
569
do_proc_douintvec_w(unsigned int * tbl_data,struct ctl_table * table,void * buffer,size_t * lenp,loff_t * ppos,int (* conv)(unsigned long * lvalp,unsigned int * valp,int write,void * data),void * data)570 static int do_proc_douintvec_w(unsigned int *tbl_data,
571 struct ctl_table *table,
572 void *buffer,
573 size_t *lenp, loff_t *ppos,
574 int (*conv)(unsigned long *lvalp,
575 unsigned int *valp,
576 int write, void *data),
577 void *data)
578 {
579 unsigned long lval;
580 int err = 0;
581 size_t left;
582 bool neg;
583 char *p = buffer;
584
585 left = *lenp;
586
587 if (proc_first_pos_non_zero_ignore(ppos, table))
588 goto bail_early;
589
590 if (left > PAGE_SIZE - 1)
591 left = PAGE_SIZE - 1;
592
593 proc_skip_spaces(&p, &left);
594 if (!left) {
595 err = -EINVAL;
596 goto out_free;
597 }
598
599 err = proc_get_long(&p, &left, &lval, &neg,
600 proc_wspace_sep,
601 sizeof(proc_wspace_sep), NULL);
602 if (err || neg) {
603 err = -EINVAL;
604 goto out_free;
605 }
606
607 if (conv(&lval, tbl_data, 1, data)) {
608 err = -EINVAL;
609 goto out_free;
610 }
611
612 if (!err && left)
613 proc_skip_spaces(&p, &left);
614
615 out_free:
616 if (err)
617 return -EINVAL;
618
619 return 0;
620
621 /* This is in keeping with old __do_proc_dointvec() */
622 bail_early:
623 *ppos += *lenp;
624 return err;
625 }
626
do_proc_douintvec_r(unsigned int * tbl_data,void * buffer,size_t * lenp,loff_t * ppos,int (* conv)(unsigned long * lvalp,unsigned int * valp,int write,void * data),void * data)627 static int do_proc_douintvec_r(unsigned int *tbl_data, void *buffer,
628 size_t *lenp, loff_t *ppos,
629 int (*conv)(unsigned long *lvalp,
630 unsigned int *valp,
631 int write, void *data),
632 void *data)
633 {
634 unsigned long lval;
635 int err = 0;
636 size_t left;
637
638 left = *lenp;
639
640 if (conv(&lval, tbl_data, 0, data)) {
641 err = -EINVAL;
642 goto out;
643 }
644
645 proc_put_long(&buffer, &left, lval, false);
646 if (!left)
647 goto out;
648
649 proc_put_char(&buffer, &left, '\n');
650
651 out:
652 *lenp -= left;
653 *ppos += *lenp;
654
655 return err;
656 }
657
__do_proc_douintvec(void * tbl_data,struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos,int (* conv)(unsigned long * lvalp,unsigned int * valp,int write,void * data),void * data)658 static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
659 int write, void *buffer,
660 size_t *lenp, loff_t *ppos,
661 int (*conv)(unsigned long *lvalp,
662 unsigned int *valp,
663 int write, void *data),
664 void *data)
665 {
666 unsigned int *i, vleft;
667
668 if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
669 *lenp = 0;
670 return 0;
671 }
672
673 i = (unsigned int *) tbl_data;
674 vleft = table->maxlen / sizeof(*i);
675
676 /*
677 * Arrays are not supported, keep this simple. *Do not* add
678 * support for them.
679 */
680 if (vleft != 1) {
681 *lenp = 0;
682 return -EINVAL;
683 }
684
685 if (!conv)
686 conv = do_proc_douintvec_conv;
687
688 if (write)
689 return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
690 conv, data);
691 return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
692 }
693
do_proc_douintvec(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos,int (* conv)(unsigned long * lvalp,unsigned int * valp,int write,void * data),void * data)694 int do_proc_douintvec(struct ctl_table *table, int write,
695 void *buffer, size_t *lenp, loff_t *ppos,
696 int (*conv)(unsigned long *lvalp,
697 unsigned int *valp,
698 int write, void *data),
699 void *data)
700 {
701 return __do_proc_douintvec(table->data, table, write,
702 buffer, lenp, ppos, conv, data);
703 }
704
705 /**
706 * proc_dobool - read/write a bool
707 * @table: the sysctl table
708 * @write: %TRUE if this is a write to the sysctl file
709 * @buffer: the user buffer
710 * @lenp: the size of the user buffer
711 * @ppos: file position
712 *
713 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
714 * values from/to the user buffer, treated as an ASCII string.
715 *
716 * Returns 0 on success.
717 */
proc_dobool(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)718 int proc_dobool(struct ctl_table *table, int write, void *buffer,
719 size_t *lenp, loff_t *ppos)
720 {
721 return do_proc_dointvec(table, write, buffer, lenp, ppos,
722 do_proc_dobool_conv, NULL);
723 }
724
725 /**
726 * proc_dointvec - read a vector of integers
727 * @table: the sysctl table
728 * @write: %TRUE if this is a write to the sysctl file
729 * @buffer: the user buffer
730 * @lenp: the size of the user buffer
731 * @ppos: file position
732 *
733 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
734 * values from/to the user buffer, treated as an ASCII string.
735 *
736 * Returns 0 on success.
737 */
proc_dointvec(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)738 int proc_dointvec(struct ctl_table *table, int write, void *buffer,
739 size_t *lenp, loff_t *ppos)
740 {
741 return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
742 }
743
744 #ifdef CONFIG_COMPACTION
proc_dointvec_minmax_warn_RT_change(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)745 static int proc_dointvec_minmax_warn_RT_change(struct ctl_table *table,
746 int write, void *buffer, size_t *lenp, loff_t *ppos)
747 {
748 int ret, old;
749
750 if (!IS_ENABLED(CONFIG_PREEMPT_RT) || !write)
751 return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
752
753 old = *(int *)table->data;
754 ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
755 if (ret)
756 return ret;
757 if (old != *(int *)table->data)
758 pr_warn_once("sysctl attribute %s changed by %s[%d]\n",
759 table->procname, current->comm,
760 task_pid_nr(current));
761 return ret;
762 }
763 #endif
764
765 /**
766 * proc_douintvec - read a vector of unsigned integers
767 * @table: the sysctl table
768 * @write: %TRUE if this is a write to the sysctl file
769 * @buffer: the user buffer
770 * @lenp: the size of the user buffer
771 * @ppos: file position
772 *
773 * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
774 * values from/to the user buffer, treated as an ASCII string.
775 *
776 * Returns 0 on success.
777 */
proc_douintvec(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)778 int proc_douintvec(struct ctl_table *table, int write, void *buffer,
779 size_t *lenp, loff_t *ppos)
780 {
781 return do_proc_douintvec(table, write, buffer, lenp, ppos,
782 do_proc_douintvec_conv, NULL);
783 }
784
785 /*
786 * Taint values can only be increased
787 * This means we can safely use a temporary.
788 */
proc_taint(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)789 static int proc_taint(struct ctl_table *table, int write,
790 void *buffer, size_t *lenp, loff_t *ppos)
791 {
792 struct ctl_table t;
793 unsigned long tmptaint = get_taint();
794 int err;
795
796 if (write && !capable(CAP_SYS_ADMIN))
797 return -EPERM;
798
799 t = *table;
800 t.data = &tmptaint;
801 err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
802 if (err < 0)
803 return err;
804
805 if (write) {
806 int i;
807
808 /*
809 * If we are relying on panic_on_taint not producing
810 * false positives due to userspace input, bail out
811 * before setting the requested taint flags.
812 */
813 if (panic_on_taint_nousertaint && (tmptaint & panic_on_taint))
814 return -EINVAL;
815
816 /*
817 * Poor man's atomic or. Not worth adding a primitive
818 * to everyone's atomic.h for this
819 */
820 for (i = 0; i < TAINT_FLAGS_COUNT; i++)
821 if ((1UL << i) & tmptaint)
822 add_taint(i, LOCKDEP_STILL_OK);
823 }
824
825 return err;
826 }
827
828 /**
829 * struct do_proc_dointvec_minmax_conv_param - proc_dointvec_minmax() range checking structure
830 * @min: pointer to minimum allowable value
831 * @max: pointer to maximum allowable value
832 *
833 * The do_proc_dointvec_minmax_conv_param structure provides the
834 * minimum and maximum values for doing range checking for those sysctl
835 * parameters that use the proc_dointvec_minmax() handler.
836 */
837 struct do_proc_dointvec_minmax_conv_param {
838 int *min;
839 int *max;
840 };
841
do_proc_dointvec_minmax_conv(bool * negp,unsigned long * lvalp,int * valp,int write,void * data)842 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
843 int *valp,
844 int write, void *data)
845 {
846 int tmp, ret;
847 struct do_proc_dointvec_minmax_conv_param *param = data;
848 /*
849 * If writing, first do so via a temporary local int so we can
850 * bounds-check it before touching *valp.
851 */
852 int *ip = write ? &tmp : valp;
853
854 ret = do_proc_dointvec_conv(negp, lvalp, ip, write, data);
855 if (ret)
856 return ret;
857
858 if (write) {
859 if ((param->min && *param->min > tmp) ||
860 (param->max && *param->max < tmp))
861 return -EINVAL;
862 WRITE_ONCE(*valp, tmp);
863 }
864
865 return 0;
866 }
867
868 /**
869 * proc_dointvec_minmax - read a vector of integers with min/max values
870 * @table: the sysctl table
871 * @write: %TRUE if this is a write to the sysctl file
872 * @buffer: the user buffer
873 * @lenp: the size of the user buffer
874 * @ppos: file position
875 *
876 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
877 * values from/to the user buffer, treated as an ASCII string.
878 *
879 * This routine will ensure the values are within the range specified by
880 * table->extra1 (min) and table->extra2 (max).
881 *
882 * Returns 0 on success or -EINVAL on write when the range check fails.
883 */
proc_dointvec_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)884 int proc_dointvec_minmax(struct ctl_table *table, int write,
885 void *buffer, size_t *lenp, loff_t *ppos)
886 {
887 struct do_proc_dointvec_minmax_conv_param param = {
888 .min = (int *) table->extra1,
889 .max = (int *) table->extra2,
890 };
891 return do_proc_dointvec(table, write, buffer, lenp, ppos,
892 do_proc_dointvec_minmax_conv, ¶m);
893 }
894
895 /**
896 * struct do_proc_douintvec_minmax_conv_param - proc_douintvec_minmax() range checking structure
897 * @min: pointer to minimum allowable value
898 * @max: pointer to maximum allowable value
899 *
900 * The do_proc_douintvec_minmax_conv_param structure provides the
901 * minimum and maximum values for doing range checking for those sysctl
902 * parameters that use the proc_douintvec_minmax() handler.
903 */
904 struct do_proc_douintvec_minmax_conv_param {
905 unsigned int *min;
906 unsigned int *max;
907 };
908
do_proc_douintvec_minmax_conv(unsigned long * lvalp,unsigned int * valp,int write,void * data)909 static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
910 unsigned int *valp,
911 int write, void *data)
912 {
913 int ret;
914 unsigned int tmp;
915 struct do_proc_douintvec_minmax_conv_param *param = data;
916 /* write via temporary local uint for bounds-checking */
917 unsigned int *up = write ? &tmp : valp;
918
919 ret = do_proc_douintvec_conv(lvalp, up, write, data);
920 if (ret)
921 return ret;
922
923 if (write) {
924 if ((param->min && *param->min > tmp) ||
925 (param->max && *param->max < tmp))
926 return -ERANGE;
927
928 WRITE_ONCE(*valp, tmp);
929 }
930
931 return 0;
932 }
933
934 /**
935 * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
936 * @table: the sysctl table
937 * @write: %TRUE if this is a write to the sysctl file
938 * @buffer: the user buffer
939 * @lenp: the size of the user buffer
940 * @ppos: file position
941 *
942 * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
943 * values from/to the user buffer, treated as an ASCII string. Negative
944 * strings are not allowed.
945 *
946 * This routine will ensure the values are within the range specified by
947 * table->extra1 (min) and table->extra2 (max). There is a final sanity
948 * check for UINT_MAX to avoid having to support wrap around uses from
949 * userspace.
950 *
951 * Returns 0 on success or -ERANGE on write when the range check fails.
952 */
proc_douintvec_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)953 int proc_douintvec_minmax(struct ctl_table *table, int write,
954 void *buffer, size_t *lenp, loff_t *ppos)
955 {
956 struct do_proc_douintvec_minmax_conv_param param = {
957 .min = (unsigned int *) table->extra1,
958 .max = (unsigned int *) table->extra2,
959 };
960 return do_proc_douintvec(table, write, buffer, lenp, ppos,
961 do_proc_douintvec_minmax_conv, ¶m);
962 }
963
964 /**
965 * proc_dou8vec_minmax - read a vector of unsigned chars with min/max values
966 * @table: the sysctl table
967 * @write: %TRUE if this is a write to the sysctl file
968 * @buffer: the user buffer
969 * @lenp: the size of the user buffer
970 * @ppos: file position
971 *
972 * Reads/writes up to table->maxlen/sizeof(u8) unsigned chars
973 * values from/to the user buffer, treated as an ASCII string. Negative
974 * strings are not allowed.
975 *
976 * This routine will ensure the values are within the range specified by
977 * table->extra1 (min) and table->extra2 (max).
978 *
979 * Returns 0 on success or an error on write when the range check fails.
980 */
proc_dou8vec_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)981 int proc_dou8vec_minmax(struct ctl_table *table, int write,
982 void *buffer, size_t *lenp, loff_t *ppos)
983 {
984 struct ctl_table tmp;
985 unsigned int min = 0, max = 255U, val;
986 u8 *data = table->data;
987 struct do_proc_douintvec_minmax_conv_param param = {
988 .min = &min,
989 .max = &max,
990 };
991 int res;
992
993 /* Do not support arrays yet. */
994 if (table->maxlen != sizeof(u8))
995 return -EINVAL;
996
997 if (table->extra1) {
998 min = *(unsigned int *) table->extra1;
999 if (min > 255U)
1000 return -EINVAL;
1001 }
1002 if (table->extra2) {
1003 max = *(unsigned int *) table->extra2;
1004 if (max > 255U)
1005 return -EINVAL;
1006 }
1007
1008 tmp = *table;
1009
1010 tmp.maxlen = sizeof(val);
1011 tmp.data = &val;
1012 val = READ_ONCE(*data);
1013 res = do_proc_douintvec(&tmp, write, buffer, lenp, ppos,
1014 do_proc_douintvec_minmax_conv, ¶m);
1015 if (res)
1016 return res;
1017 if (write)
1018 WRITE_ONCE(*data, val);
1019 return 0;
1020 }
1021 EXPORT_SYMBOL_GPL(proc_dou8vec_minmax);
1022
1023 #ifdef CONFIG_MAGIC_SYSRQ
sysrq_sysctl_handler(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1024 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
1025 void *buffer, size_t *lenp, loff_t *ppos)
1026 {
1027 int tmp, ret;
1028
1029 tmp = sysrq_mask();
1030
1031 ret = __do_proc_dointvec(&tmp, table, write, buffer,
1032 lenp, ppos, NULL, NULL);
1033 if (ret || !write)
1034 return ret;
1035
1036 if (write)
1037 sysrq_toggle_support(tmp);
1038
1039 return 0;
1040 }
1041 #endif
1042
__do_proc_doulongvec_minmax(void * data,struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos,unsigned long convmul,unsigned long convdiv)1043 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table,
1044 int write, void *buffer, size_t *lenp, loff_t *ppos,
1045 unsigned long convmul, unsigned long convdiv)
1046 {
1047 unsigned long *i, *min, *max;
1048 int vleft, first = 1, err = 0;
1049 size_t left;
1050 char *p;
1051
1052 if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
1053 *lenp = 0;
1054 return 0;
1055 }
1056
1057 i = data;
1058 min = table->extra1;
1059 max = table->extra2;
1060 vleft = table->maxlen / sizeof(unsigned long);
1061 left = *lenp;
1062
1063 if (write) {
1064 if (proc_first_pos_non_zero_ignore(ppos, table))
1065 goto out;
1066
1067 if (left > PAGE_SIZE - 1)
1068 left = PAGE_SIZE - 1;
1069 p = buffer;
1070 }
1071
1072 for (; left && vleft--; i++, first = 0) {
1073 unsigned long val;
1074
1075 if (write) {
1076 bool neg;
1077
1078 proc_skip_spaces(&p, &left);
1079 if (!left)
1080 break;
1081
1082 err = proc_get_long(&p, &left, &val, &neg,
1083 proc_wspace_sep,
1084 sizeof(proc_wspace_sep), NULL);
1085 if (err || neg) {
1086 err = -EINVAL;
1087 break;
1088 }
1089
1090 val = convmul * val / convdiv;
1091 if ((min && val < *min) || (max && val > *max)) {
1092 err = -EINVAL;
1093 break;
1094 }
1095 WRITE_ONCE(*i, val);
1096 } else {
1097 val = convdiv * READ_ONCE(*i) / convmul;
1098 if (!first)
1099 proc_put_char(&buffer, &left, '\t');
1100 proc_put_long(&buffer, &left, val, false);
1101 }
1102 }
1103
1104 if (!write && !first && left && !err)
1105 proc_put_char(&buffer, &left, '\n');
1106 if (write && !err)
1107 proc_skip_spaces(&p, &left);
1108 if (write && first)
1109 return err ? : -EINVAL;
1110 *lenp -= left;
1111 out:
1112 *ppos += *lenp;
1113 return err;
1114 }
1115
do_proc_doulongvec_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos,unsigned long convmul,unsigned long convdiv)1116 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
1117 void *buffer, size_t *lenp, loff_t *ppos, unsigned long convmul,
1118 unsigned long convdiv)
1119 {
1120 return __do_proc_doulongvec_minmax(table->data, table, write,
1121 buffer, lenp, ppos, convmul, convdiv);
1122 }
1123
1124 /**
1125 * proc_doulongvec_minmax - read a vector of long integers with min/max values
1126 * @table: the sysctl table
1127 * @write: %TRUE if this is a write to the sysctl file
1128 * @buffer: the user buffer
1129 * @lenp: the size of the user buffer
1130 * @ppos: file position
1131 *
1132 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1133 * values from/to the user buffer, treated as an ASCII string.
1134 *
1135 * This routine will ensure the values are within the range specified by
1136 * table->extra1 (min) and table->extra2 (max).
1137 *
1138 * Returns 0 on success.
1139 */
proc_doulongvec_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1140 int proc_doulongvec_minmax(struct ctl_table *table, int write,
1141 void *buffer, size_t *lenp, loff_t *ppos)
1142 {
1143 return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
1144 }
1145
1146 /**
1147 * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
1148 * @table: the sysctl table
1149 * @write: %TRUE if this is a write to the sysctl file
1150 * @buffer: the user buffer
1151 * @lenp: the size of the user buffer
1152 * @ppos: file position
1153 *
1154 * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
1155 * values from/to the user buffer, treated as an ASCII string. The values
1156 * are treated as milliseconds, and converted to jiffies when they are stored.
1157 *
1158 * This routine will ensure the values are within the range specified by
1159 * table->extra1 (min) and table->extra2 (max).
1160 *
1161 * Returns 0 on success.
1162 */
proc_doulongvec_ms_jiffies_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1163 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
1164 void *buffer, size_t *lenp, loff_t *ppos)
1165 {
1166 return do_proc_doulongvec_minmax(table, write, buffer,
1167 lenp, ppos, HZ, 1000l);
1168 }
1169
1170
do_proc_dointvec_jiffies_conv(bool * negp,unsigned long * lvalp,int * valp,int write,void * data)1171 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
1172 int *valp,
1173 int write, void *data)
1174 {
1175 if (write) {
1176 if (*lvalp > INT_MAX / HZ)
1177 return 1;
1178 if (*negp)
1179 WRITE_ONCE(*valp, -*lvalp * HZ);
1180 else
1181 WRITE_ONCE(*valp, *lvalp * HZ);
1182 } else {
1183 int val = READ_ONCE(*valp);
1184 unsigned long lval;
1185 if (val < 0) {
1186 *negp = true;
1187 lval = -(unsigned long)val;
1188 } else {
1189 *negp = false;
1190 lval = (unsigned long)val;
1191 }
1192 *lvalp = lval / HZ;
1193 }
1194 return 0;
1195 }
1196
do_proc_dointvec_userhz_jiffies_conv(bool * negp,unsigned long * lvalp,int * valp,int write,void * data)1197 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
1198 int *valp,
1199 int write, void *data)
1200 {
1201 if (write) {
1202 if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
1203 return 1;
1204 *valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
1205 } else {
1206 int val = *valp;
1207 unsigned long lval;
1208 if (val < 0) {
1209 *negp = true;
1210 lval = -(unsigned long)val;
1211 } else {
1212 *negp = false;
1213 lval = (unsigned long)val;
1214 }
1215 *lvalp = jiffies_to_clock_t(lval);
1216 }
1217 return 0;
1218 }
1219
do_proc_dointvec_ms_jiffies_conv(bool * negp,unsigned long * lvalp,int * valp,int write,void * data)1220 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
1221 int *valp,
1222 int write, void *data)
1223 {
1224 if (write) {
1225 unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
1226
1227 if (jif > INT_MAX)
1228 return 1;
1229 WRITE_ONCE(*valp, (int)jif);
1230 } else {
1231 int val = READ_ONCE(*valp);
1232 unsigned long lval;
1233 if (val < 0) {
1234 *negp = true;
1235 lval = -(unsigned long)val;
1236 } else {
1237 *negp = false;
1238 lval = (unsigned long)val;
1239 }
1240 *lvalp = jiffies_to_msecs(lval);
1241 }
1242 return 0;
1243 }
1244
do_proc_dointvec_ms_jiffies_minmax_conv(bool * negp,unsigned long * lvalp,int * valp,int write,void * data)1245 static int do_proc_dointvec_ms_jiffies_minmax_conv(bool *negp, unsigned long *lvalp,
1246 int *valp, int write, void *data)
1247 {
1248 int tmp, ret;
1249 struct do_proc_dointvec_minmax_conv_param *param = data;
1250 /*
1251 * If writing, first do so via a temporary local int so we can
1252 * bounds-check it before touching *valp.
1253 */
1254 int *ip = write ? &tmp : valp;
1255
1256 ret = do_proc_dointvec_ms_jiffies_conv(negp, lvalp, ip, write, data);
1257 if (ret)
1258 return ret;
1259
1260 if (write) {
1261 if ((param->min && *param->min > tmp) ||
1262 (param->max && *param->max < tmp))
1263 return -EINVAL;
1264 *valp = tmp;
1265 }
1266 return 0;
1267 }
1268
1269 /**
1270 * proc_dointvec_jiffies - read a vector of integers as seconds
1271 * @table: the sysctl table
1272 * @write: %TRUE if this is a write to the sysctl file
1273 * @buffer: the user buffer
1274 * @lenp: the size of the user buffer
1275 * @ppos: file position
1276 *
1277 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1278 * values from/to the user buffer, treated as an ASCII string.
1279 * The values read are assumed to be in seconds, and are converted into
1280 * jiffies.
1281 *
1282 * Returns 0 on success.
1283 */
proc_dointvec_jiffies(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1284 int proc_dointvec_jiffies(struct ctl_table *table, int write,
1285 void *buffer, size_t *lenp, loff_t *ppos)
1286 {
1287 return do_proc_dointvec(table,write,buffer,lenp,ppos,
1288 do_proc_dointvec_jiffies_conv,NULL);
1289 }
1290
proc_dointvec_ms_jiffies_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1291 int proc_dointvec_ms_jiffies_minmax(struct ctl_table *table, int write,
1292 void *buffer, size_t *lenp, loff_t *ppos)
1293 {
1294 struct do_proc_dointvec_minmax_conv_param param = {
1295 .min = (int *) table->extra1,
1296 .max = (int *) table->extra2,
1297 };
1298 return do_proc_dointvec(table, write, buffer, lenp, ppos,
1299 do_proc_dointvec_ms_jiffies_minmax_conv, ¶m);
1300 }
1301
1302 /**
1303 * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
1304 * @table: the sysctl table
1305 * @write: %TRUE if this is a write to the sysctl file
1306 * @buffer: the user buffer
1307 * @lenp: the size of the user buffer
1308 * @ppos: pointer to the file position
1309 *
1310 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1311 * values from/to the user buffer, treated as an ASCII string.
1312 * The values read are assumed to be in 1/USER_HZ seconds, and
1313 * are converted into jiffies.
1314 *
1315 * Returns 0 on success.
1316 */
proc_dointvec_userhz_jiffies(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1317 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
1318 void *buffer, size_t *lenp, loff_t *ppos)
1319 {
1320 return do_proc_dointvec(table, write, buffer, lenp, ppos,
1321 do_proc_dointvec_userhz_jiffies_conv, NULL);
1322 }
1323
1324 /**
1325 * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
1326 * @table: the sysctl table
1327 * @write: %TRUE if this is a write to the sysctl file
1328 * @buffer: the user buffer
1329 * @lenp: the size of the user buffer
1330 * @ppos: file position
1331 * @ppos: the current position in the file
1332 *
1333 * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
1334 * values from/to the user buffer, treated as an ASCII string.
1335 * The values read are assumed to be in 1/1000 seconds, and
1336 * are converted into jiffies.
1337 *
1338 * Returns 0 on success.
1339 */
proc_dointvec_ms_jiffies(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1340 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write, void *buffer,
1341 size_t *lenp, loff_t *ppos)
1342 {
1343 return do_proc_dointvec(table, write, buffer, lenp, ppos,
1344 do_proc_dointvec_ms_jiffies_conv, NULL);
1345 }
1346
proc_do_cad_pid(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1347 static int proc_do_cad_pid(struct ctl_table *table, int write, void *buffer,
1348 size_t *lenp, loff_t *ppos)
1349 {
1350 struct pid *new_pid;
1351 pid_t tmp;
1352 int r;
1353
1354 tmp = pid_vnr(cad_pid);
1355
1356 r = __do_proc_dointvec(&tmp, table, write, buffer,
1357 lenp, ppos, NULL, NULL);
1358 if (r || !write)
1359 return r;
1360
1361 new_pid = find_get_pid(tmp);
1362 if (!new_pid)
1363 return -ESRCH;
1364
1365 put_pid(xchg(&cad_pid, new_pid));
1366 return 0;
1367 }
1368
1369 /**
1370 * proc_do_large_bitmap - read/write from/to a large bitmap
1371 * @table: the sysctl table
1372 * @write: %TRUE if this is a write to the sysctl file
1373 * @buffer: the user buffer
1374 * @lenp: the size of the user buffer
1375 * @ppos: file position
1376 *
1377 * The bitmap is stored at table->data and the bitmap length (in bits)
1378 * in table->maxlen.
1379 *
1380 * We use a range comma separated format (e.g. 1,3-4,10-10) so that
1381 * large bitmaps may be represented in a compact manner. Writing into
1382 * the file will clear the bitmap then update it with the given input.
1383 *
1384 * Returns 0 on success.
1385 */
proc_do_large_bitmap(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1386 int proc_do_large_bitmap(struct ctl_table *table, int write,
1387 void *buffer, size_t *lenp, loff_t *ppos)
1388 {
1389 int err = 0;
1390 size_t left = *lenp;
1391 unsigned long bitmap_len = table->maxlen;
1392 unsigned long *bitmap = *(unsigned long **) table->data;
1393 unsigned long *tmp_bitmap = NULL;
1394 char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
1395
1396 if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
1397 *lenp = 0;
1398 return 0;
1399 }
1400
1401 if (write) {
1402 char *p = buffer;
1403 size_t skipped = 0;
1404
1405 if (left > PAGE_SIZE - 1) {
1406 left = PAGE_SIZE - 1;
1407 /* How much of the buffer we'll skip this pass */
1408 skipped = *lenp - left;
1409 }
1410
1411 tmp_bitmap = bitmap_zalloc(bitmap_len, GFP_KERNEL);
1412 if (!tmp_bitmap)
1413 return -ENOMEM;
1414 proc_skip_char(&p, &left, '\n');
1415 while (!err && left) {
1416 unsigned long val_a, val_b;
1417 bool neg;
1418 size_t saved_left;
1419
1420 /* In case we stop parsing mid-number, we can reset */
1421 saved_left = left;
1422 err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
1423 sizeof(tr_a), &c);
1424 /*
1425 * If we consumed the entirety of a truncated buffer or
1426 * only one char is left (may be a "-"), then stop here,
1427 * reset, & come back for more.
1428 */
1429 if ((left <= 1) && skipped) {
1430 left = saved_left;
1431 break;
1432 }
1433
1434 if (err)
1435 break;
1436 if (val_a >= bitmap_len || neg) {
1437 err = -EINVAL;
1438 break;
1439 }
1440
1441 val_b = val_a;
1442 if (left) {
1443 p++;
1444 left--;
1445 }
1446
1447 if (c == '-') {
1448 err = proc_get_long(&p, &left, &val_b,
1449 &neg, tr_b, sizeof(tr_b),
1450 &c);
1451 /*
1452 * If we consumed all of a truncated buffer or
1453 * then stop here, reset, & come back for more.
1454 */
1455 if (!left && skipped) {
1456 left = saved_left;
1457 break;
1458 }
1459
1460 if (err)
1461 break;
1462 if (val_b >= bitmap_len || neg ||
1463 val_a > val_b) {
1464 err = -EINVAL;
1465 break;
1466 }
1467 if (left) {
1468 p++;
1469 left--;
1470 }
1471 }
1472
1473 bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
1474 proc_skip_char(&p, &left, '\n');
1475 }
1476 left += skipped;
1477 } else {
1478 unsigned long bit_a, bit_b = 0;
1479 bool first = 1;
1480
1481 while (left) {
1482 bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
1483 if (bit_a >= bitmap_len)
1484 break;
1485 bit_b = find_next_zero_bit(bitmap, bitmap_len,
1486 bit_a + 1) - 1;
1487
1488 if (!first)
1489 proc_put_char(&buffer, &left, ',');
1490 proc_put_long(&buffer, &left, bit_a, false);
1491 if (bit_a != bit_b) {
1492 proc_put_char(&buffer, &left, '-');
1493 proc_put_long(&buffer, &left, bit_b, false);
1494 }
1495
1496 first = 0; bit_b++;
1497 }
1498 proc_put_char(&buffer, &left, '\n');
1499 }
1500
1501 if (!err) {
1502 if (write) {
1503 if (*ppos)
1504 bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
1505 else
1506 bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
1507 }
1508 *lenp -= left;
1509 *ppos += *lenp;
1510 }
1511
1512 bitmap_free(tmp_bitmap);
1513 return err;
1514 }
1515
1516 #else /* CONFIG_PROC_SYSCTL */
1517
proc_dostring(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1518 int proc_dostring(struct ctl_table *table, int write,
1519 void *buffer, size_t *lenp, loff_t *ppos)
1520 {
1521 return -ENOSYS;
1522 }
1523
proc_dobool(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1524 int proc_dobool(struct ctl_table *table, int write,
1525 void *buffer, size_t *lenp, loff_t *ppos)
1526 {
1527 return -ENOSYS;
1528 }
1529
proc_dointvec(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1530 int proc_dointvec(struct ctl_table *table, int write,
1531 void *buffer, size_t *lenp, loff_t *ppos)
1532 {
1533 return -ENOSYS;
1534 }
1535
proc_douintvec(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1536 int proc_douintvec(struct ctl_table *table, int write,
1537 void *buffer, size_t *lenp, loff_t *ppos)
1538 {
1539 return -ENOSYS;
1540 }
1541
proc_dointvec_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1542 int proc_dointvec_minmax(struct ctl_table *table, int write,
1543 void *buffer, size_t *lenp, loff_t *ppos)
1544 {
1545 return -ENOSYS;
1546 }
1547
proc_douintvec_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1548 int proc_douintvec_minmax(struct ctl_table *table, int write,
1549 void *buffer, size_t *lenp, loff_t *ppos)
1550 {
1551 return -ENOSYS;
1552 }
1553
proc_dou8vec_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1554 int proc_dou8vec_minmax(struct ctl_table *table, int write,
1555 void *buffer, size_t *lenp, loff_t *ppos)
1556 {
1557 return -ENOSYS;
1558 }
1559
proc_dointvec_jiffies(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1560 int proc_dointvec_jiffies(struct ctl_table *table, int write,
1561 void *buffer, size_t *lenp, loff_t *ppos)
1562 {
1563 return -ENOSYS;
1564 }
1565
proc_dointvec_ms_jiffies_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1566 int proc_dointvec_ms_jiffies_minmax(struct ctl_table *table, int write,
1567 void *buffer, size_t *lenp, loff_t *ppos)
1568 {
1569 return -ENOSYS;
1570 }
1571
proc_dointvec_userhz_jiffies(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1572 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
1573 void *buffer, size_t *lenp, loff_t *ppos)
1574 {
1575 return -ENOSYS;
1576 }
1577
proc_dointvec_ms_jiffies(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1578 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
1579 void *buffer, size_t *lenp, loff_t *ppos)
1580 {
1581 return -ENOSYS;
1582 }
1583
proc_doulongvec_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1584 int proc_doulongvec_minmax(struct ctl_table *table, int write,
1585 void *buffer, size_t *lenp, loff_t *ppos)
1586 {
1587 return -ENOSYS;
1588 }
1589
proc_doulongvec_ms_jiffies_minmax(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1590 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
1591 void *buffer, size_t *lenp, loff_t *ppos)
1592 {
1593 return -ENOSYS;
1594 }
1595
proc_do_large_bitmap(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1596 int proc_do_large_bitmap(struct ctl_table *table, int write,
1597 void *buffer, size_t *lenp, loff_t *ppos)
1598 {
1599 return -ENOSYS;
1600 }
1601
1602 #endif /* CONFIG_PROC_SYSCTL */
1603
1604 #if defined(CONFIG_SYSCTL)
proc_do_static_key(struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)1605 int proc_do_static_key(struct ctl_table *table, int write,
1606 void *buffer, size_t *lenp, loff_t *ppos)
1607 {
1608 struct static_key *key = (struct static_key *)table->data;
1609 static DEFINE_MUTEX(static_key_mutex);
1610 int val, ret;
1611 struct ctl_table tmp = {
1612 .data = &val,
1613 .maxlen = sizeof(val),
1614 .mode = table->mode,
1615 .extra1 = SYSCTL_ZERO,
1616 .extra2 = SYSCTL_ONE,
1617 };
1618
1619 if (write && !capable(CAP_SYS_ADMIN))
1620 return -EPERM;
1621
1622 mutex_lock(&static_key_mutex);
1623 val = static_key_enabled(key);
1624 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
1625 if (write && !ret) {
1626 if (val)
1627 static_key_enable(key);
1628 else
1629 static_key_disable(key);
1630 }
1631 mutex_unlock(&static_key_mutex);
1632 return ret;
1633 }
1634
1635 static struct ctl_table kern_table[] = {
1636 #ifdef CONFIG_NUMA_BALANCING
1637 {
1638 .procname = "numa_balancing",
1639 .data = NULL, /* filled in by handler */
1640 .maxlen = sizeof(unsigned int),
1641 .mode = 0644,
1642 .proc_handler = sysctl_numa_balancing,
1643 .extra1 = SYSCTL_ZERO,
1644 .extra2 = SYSCTL_FOUR,
1645 },
1646 {
1647 .procname = "numa_balancing_promote_rate_limit_MBps",
1648 .data = &sysctl_numa_balancing_promote_rate_limit,
1649 .maxlen = sizeof(unsigned int),
1650 .mode = 0644,
1651 .proc_handler = proc_dointvec_minmax,
1652 .extra1 = SYSCTL_ZERO,
1653 },
1654 #endif /* CONFIG_NUMA_BALANCING */
1655 {
1656 .procname = "panic",
1657 .data = &panic_timeout,
1658 .maxlen = sizeof(int),
1659 .mode = 0644,
1660 .proc_handler = proc_dointvec,
1661 },
1662 #ifdef CONFIG_PROC_SYSCTL
1663 {
1664 .procname = "tainted",
1665 .maxlen = sizeof(long),
1666 .mode = 0644,
1667 .proc_handler = proc_taint,
1668 },
1669 {
1670 .procname = "sysctl_writes_strict",
1671 .data = &sysctl_writes_strict,
1672 .maxlen = sizeof(int),
1673 .mode = 0644,
1674 .proc_handler = proc_dointvec_minmax,
1675 .extra1 = SYSCTL_NEG_ONE,
1676 .extra2 = SYSCTL_ONE,
1677 },
1678 #endif
1679 {
1680 .procname = "print-fatal-signals",
1681 .data = &print_fatal_signals,
1682 .maxlen = sizeof(int),
1683 .mode = 0644,
1684 .proc_handler = proc_dointvec,
1685 },
1686 #ifdef CONFIG_SPARC
1687 {
1688 .procname = "reboot-cmd",
1689 .data = reboot_command,
1690 .maxlen = 256,
1691 .mode = 0644,
1692 .proc_handler = proc_dostring,
1693 },
1694 {
1695 .procname = "stop-a",
1696 .data = &stop_a_enabled,
1697 .maxlen = sizeof (int),
1698 .mode = 0644,
1699 .proc_handler = proc_dointvec,
1700 },
1701 {
1702 .procname = "scons-poweroff",
1703 .data = &scons_pwroff,
1704 .maxlen = sizeof (int),
1705 .mode = 0644,
1706 .proc_handler = proc_dointvec,
1707 },
1708 #endif
1709 #ifdef CONFIG_SPARC64
1710 {
1711 .procname = "tsb-ratio",
1712 .data = &sysctl_tsb_ratio,
1713 .maxlen = sizeof (int),
1714 .mode = 0644,
1715 .proc_handler = proc_dointvec,
1716 },
1717 #endif
1718 #ifdef CONFIG_PARISC
1719 {
1720 .procname = "soft-power",
1721 .data = &pwrsw_enabled,
1722 .maxlen = sizeof (int),
1723 .mode = 0644,
1724 .proc_handler = proc_dointvec,
1725 },
1726 #endif
1727 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
1728 {
1729 .procname = "unaligned-trap",
1730 .data = &unaligned_enabled,
1731 .maxlen = sizeof (int),
1732 .mode = 0644,
1733 .proc_handler = proc_dointvec,
1734 },
1735 #endif
1736 #ifdef CONFIG_STACK_TRACER
1737 {
1738 .procname = "stack_tracer_enabled",
1739 .data = &stack_tracer_enabled,
1740 .maxlen = sizeof(int),
1741 .mode = 0644,
1742 .proc_handler = stack_trace_sysctl,
1743 },
1744 #endif
1745 #ifdef CONFIG_TRACING
1746 {
1747 .procname = "ftrace_dump_on_oops",
1748 .data = &ftrace_dump_on_oops,
1749 .maxlen = sizeof(int),
1750 .mode = 0644,
1751 .proc_handler = proc_dointvec,
1752 },
1753 {
1754 .procname = "traceoff_on_warning",
1755 .data = &__disable_trace_on_warning,
1756 .maxlen = sizeof(__disable_trace_on_warning),
1757 .mode = 0644,
1758 .proc_handler = proc_dointvec,
1759 },
1760 {
1761 .procname = "tracepoint_printk",
1762 .data = &tracepoint_printk,
1763 .maxlen = sizeof(tracepoint_printk),
1764 .mode = 0644,
1765 .proc_handler = tracepoint_printk_sysctl,
1766 },
1767 #endif
1768 #ifdef CONFIG_MODULES
1769 {
1770 .procname = "modprobe",
1771 .data = &modprobe_path,
1772 .maxlen = KMOD_PATH_LEN,
1773 .mode = 0644,
1774 .proc_handler = proc_dostring,
1775 },
1776 {
1777 .procname = "modules_disabled",
1778 .data = &modules_disabled,
1779 .maxlen = sizeof(int),
1780 .mode = 0644,
1781 /* only handle a transition from default "0" to "1" */
1782 .proc_handler = proc_dointvec_minmax,
1783 .extra1 = SYSCTL_ONE,
1784 .extra2 = SYSCTL_ONE,
1785 },
1786 #endif
1787 #ifdef CONFIG_UEVENT_HELPER
1788 {
1789 .procname = "hotplug",
1790 .data = &uevent_helper,
1791 .maxlen = UEVENT_HELPER_PATH_LEN,
1792 .mode = 0644,
1793 .proc_handler = proc_dostring,
1794 },
1795 #endif
1796 #ifdef CONFIG_MAGIC_SYSRQ
1797 {
1798 .procname = "sysrq",
1799 .data = NULL,
1800 .maxlen = sizeof (int),
1801 .mode = 0644,
1802 .proc_handler = sysrq_sysctl_handler,
1803 },
1804 #endif
1805 #ifdef CONFIG_PROC_SYSCTL
1806 {
1807 .procname = "cad_pid",
1808 .data = NULL,
1809 .maxlen = sizeof (int),
1810 .mode = 0600,
1811 .proc_handler = proc_do_cad_pid,
1812 },
1813 #endif
1814 {
1815 .procname = "threads-max",
1816 .data = NULL,
1817 .maxlen = sizeof(int),
1818 .mode = 0644,
1819 .proc_handler = sysctl_max_threads,
1820 },
1821 {
1822 .procname = "usermodehelper",
1823 .mode = 0555,
1824 .child = usermodehelper_table,
1825 },
1826 {
1827 .procname = "overflowuid",
1828 .data = &overflowuid,
1829 .maxlen = sizeof(int),
1830 .mode = 0644,
1831 .proc_handler = proc_dointvec_minmax,
1832 .extra1 = SYSCTL_ZERO,
1833 .extra2 = SYSCTL_MAXOLDUID,
1834 },
1835 {
1836 .procname = "overflowgid",
1837 .data = &overflowgid,
1838 .maxlen = sizeof(int),
1839 .mode = 0644,
1840 .proc_handler = proc_dointvec_minmax,
1841 .extra1 = SYSCTL_ZERO,
1842 .extra2 = SYSCTL_MAXOLDUID,
1843 },
1844 #ifdef CONFIG_S390
1845 {
1846 .procname = "userprocess_debug",
1847 .data = &show_unhandled_signals,
1848 .maxlen = sizeof(int),
1849 .mode = 0644,
1850 .proc_handler = proc_dointvec,
1851 },
1852 #endif
1853 {
1854 .procname = "pid_max",
1855 .data = &pid_max,
1856 .maxlen = sizeof (int),
1857 .mode = 0644,
1858 .proc_handler = proc_dointvec_minmax,
1859 .extra1 = &pid_max_min,
1860 .extra2 = &pid_max_max,
1861 },
1862 {
1863 .procname = "panic_on_oops",
1864 .data = &panic_on_oops,
1865 .maxlen = sizeof(int),
1866 .mode = 0644,
1867 .proc_handler = proc_dointvec,
1868 },
1869 {
1870 .procname = "panic_print",
1871 .data = &panic_print,
1872 .maxlen = sizeof(unsigned long),
1873 .mode = 0644,
1874 .proc_handler = proc_doulongvec_minmax,
1875 },
1876 {
1877 .procname = "ngroups_max",
1878 .data = (void *)&ngroups_max,
1879 .maxlen = sizeof (int),
1880 .mode = 0444,
1881 .proc_handler = proc_dointvec,
1882 },
1883 {
1884 .procname = "cap_last_cap",
1885 .data = (void *)&cap_last_cap,
1886 .maxlen = sizeof(int),
1887 .mode = 0444,
1888 .proc_handler = proc_dointvec,
1889 },
1890 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
1891 {
1892 .procname = "unknown_nmi_panic",
1893 .data = &unknown_nmi_panic,
1894 .maxlen = sizeof (int),
1895 .mode = 0644,
1896 .proc_handler = proc_dointvec,
1897 },
1898 #endif
1899
1900 #if (defined(CONFIG_X86_32) || defined(CONFIG_PARISC)) && \
1901 defined(CONFIG_DEBUG_STACKOVERFLOW)
1902 {
1903 .procname = "panic_on_stackoverflow",
1904 .data = &sysctl_panic_on_stackoverflow,
1905 .maxlen = sizeof(int),
1906 .mode = 0644,
1907 .proc_handler = proc_dointvec,
1908 },
1909 #endif
1910 #if defined(CONFIG_X86)
1911 {
1912 .procname = "panic_on_unrecovered_nmi",
1913 .data = &panic_on_unrecovered_nmi,
1914 .maxlen = sizeof(int),
1915 .mode = 0644,
1916 .proc_handler = proc_dointvec,
1917 },
1918 {
1919 .procname = "panic_on_io_nmi",
1920 .data = &panic_on_io_nmi,
1921 .maxlen = sizeof(int),
1922 .mode = 0644,
1923 .proc_handler = proc_dointvec,
1924 },
1925 {
1926 .procname = "bootloader_type",
1927 .data = &bootloader_type,
1928 .maxlen = sizeof (int),
1929 .mode = 0444,
1930 .proc_handler = proc_dointvec,
1931 },
1932 {
1933 .procname = "bootloader_version",
1934 .data = &bootloader_version,
1935 .maxlen = sizeof (int),
1936 .mode = 0444,
1937 .proc_handler = proc_dointvec,
1938 },
1939 {
1940 .procname = "io_delay_type",
1941 .data = &io_delay_type,
1942 .maxlen = sizeof(int),
1943 .mode = 0644,
1944 .proc_handler = proc_dointvec,
1945 },
1946 #endif
1947 #if defined(CONFIG_MMU)
1948 {
1949 .procname = "randomize_va_space",
1950 .data = &randomize_va_space,
1951 .maxlen = sizeof(int),
1952 .mode = 0644,
1953 .proc_handler = proc_dointvec,
1954 },
1955 #endif
1956 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1957 {
1958 .procname = "spin_retry",
1959 .data = &spin_retry,
1960 .maxlen = sizeof (int),
1961 .mode = 0644,
1962 .proc_handler = proc_dointvec,
1963 },
1964 #endif
1965 #if defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1966 {
1967 .procname = "acpi_video_flags",
1968 .data = &acpi_realmode_flags,
1969 .maxlen = sizeof (unsigned long),
1970 .mode = 0644,
1971 .proc_handler = proc_doulongvec_minmax,
1972 },
1973 #endif
1974 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1975 {
1976 .procname = "ignore-unaligned-usertrap",
1977 .data = &no_unaligned_warning,
1978 .maxlen = sizeof (int),
1979 .mode = 0644,
1980 .proc_handler = proc_dointvec,
1981 },
1982 #endif
1983 #ifdef CONFIG_IA64
1984 {
1985 .procname = "unaligned-dump-stack",
1986 .data = &unaligned_dump_stack,
1987 .maxlen = sizeof (int),
1988 .mode = 0644,
1989 .proc_handler = proc_dointvec,
1990 },
1991 #endif
1992 #ifdef CONFIG_RT_MUTEXES
1993 {
1994 .procname = "max_lock_depth",
1995 .data = &max_lock_depth,
1996 .maxlen = sizeof(int),
1997 .mode = 0644,
1998 .proc_handler = proc_dointvec,
1999 },
2000 #endif
2001 #ifdef CONFIG_KEYS
2002 {
2003 .procname = "keys",
2004 .mode = 0555,
2005 .child = key_sysctls,
2006 },
2007 #endif
2008 #ifdef CONFIG_PERF_EVENTS
2009 /*
2010 * User-space scripts rely on the existence of this file
2011 * as a feature check for perf_events being enabled.
2012 *
2013 * So it's an ABI, do not remove!
2014 */
2015 {
2016 .procname = "perf_event_paranoid",
2017 .data = &sysctl_perf_event_paranoid,
2018 .maxlen = sizeof(sysctl_perf_event_paranoid),
2019 .mode = 0644,
2020 .proc_handler = proc_dointvec,
2021 },
2022 {
2023 .procname = "perf_event_mlock_kb",
2024 .data = &sysctl_perf_event_mlock,
2025 .maxlen = sizeof(sysctl_perf_event_mlock),
2026 .mode = 0644,
2027 .proc_handler = proc_dointvec,
2028 },
2029 {
2030 .procname = "perf_event_max_sample_rate",
2031 .data = &sysctl_perf_event_sample_rate,
2032 .maxlen = sizeof(sysctl_perf_event_sample_rate),
2033 .mode = 0644,
2034 .proc_handler = perf_proc_update_handler,
2035 .extra1 = SYSCTL_ONE,
2036 },
2037 {
2038 .procname = "perf_cpu_time_max_percent",
2039 .data = &sysctl_perf_cpu_time_max_percent,
2040 .maxlen = sizeof(sysctl_perf_cpu_time_max_percent),
2041 .mode = 0644,
2042 .proc_handler = perf_cpu_time_max_percent_handler,
2043 .extra1 = SYSCTL_ZERO,
2044 .extra2 = SYSCTL_ONE_HUNDRED,
2045 },
2046 {
2047 .procname = "perf_event_max_stack",
2048 .data = &sysctl_perf_event_max_stack,
2049 .maxlen = sizeof(sysctl_perf_event_max_stack),
2050 .mode = 0644,
2051 .proc_handler = perf_event_max_stack_handler,
2052 .extra1 = SYSCTL_ZERO,
2053 .extra2 = (void *)&six_hundred_forty_kb,
2054 },
2055 {
2056 .procname = "perf_event_max_contexts_per_stack",
2057 .data = &sysctl_perf_event_max_contexts_per_stack,
2058 .maxlen = sizeof(sysctl_perf_event_max_contexts_per_stack),
2059 .mode = 0644,
2060 .proc_handler = perf_event_max_stack_handler,
2061 .extra1 = SYSCTL_ZERO,
2062 .extra2 = SYSCTL_ONE_THOUSAND,
2063 },
2064 #endif
2065 {
2066 .procname = "panic_on_warn",
2067 .data = &panic_on_warn,
2068 .maxlen = sizeof(int),
2069 .mode = 0644,
2070 .proc_handler = proc_dointvec_minmax,
2071 .extra1 = SYSCTL_ZERO,
2072 .extra2 = SYSCTL_ONE,
2073 },
2074 #ifdef CONFIG_TREE_RCU
2075 {
2076 .procname = "panic_on_rcu_stall",
2077 .data = &sysctl_panic_on_rcu_stall,
2078 .maxlen = sizeof(sysctl_panic_on_rcu_stall),
2079 .mode = 0644,
2080 .proc_handler = proc_dointvec_minmax,
2081 .extra1 = SYSCTL_ZERO,
2082 .extra2 = SYSCTL_ONE,
2083 },
2084 {
2085 .procname = "max_rcu_stall_to_panic",
2086 .data = &sysctl_max_rcu_stall_to_panic,
2087 .maxlen = sizeof(sysctl_max_rcu_stall_to_panic),
2088 .mode = 0644,
2089 .proc_handler = proc_dointvec_minmax,
2090 .extra1 = SYSCTL_ONE,
2091 .extra2 = SYSCTL_INT_MAX,
2092 },
2093 #endif
2094 { }
2095 };
2096
2097 static struct ctl_table vm_table[] = {
2098 {
2099 .procname = "overcommit_memory",
2100 .data = &sysctl_overcommit_memory,
2101 .maxlen = sizeof(sysctl_overcommit_memory),
2102 .mode = 0644,
2103 .proc_handler = overcommit_policy_handler,
2104 .extra1 = SYSCTL_ZERO,
2105 .extra2 = SYSCTL_TWO,
2106 },
2107 {
2108 .procname = "overcommit_ratio",
2109 .data = &sysctl_overcommit_ratio,
2110 .maxlen = sizeof(sysctl_overcommit_ratio),
2111 .mode = 0644,
2112 .proc_handler = overcommit_ratio_handler,
2113 },
2114 {
2115 .procname = "overcommit_kbytes",
2116 .data = &sysctl_overcommit_kbytes,
2117 .maxlen = sizeof(sysctl_overcommit_kbytes),
2118 .mode = 0644,
2119 .proc_handler = overcommit_kbytes_handler,
2120 },
2121 {
2122 .procname = "page-cluster",
2123 .data = &page_cluster,
2124 .maxlen = sizeof(int),
2125 .mode = 0644,
2126 .proc_handler = proc_dointvec_minmax,
2127 .extra1 = SYSCTL_ZERO,
2128 },
2129 {
2130 .procname = "dirtytime_expire_seconds",
2131 .data = &dirtytime_expire_interval,
2132 .maxlen = sizeof(dirtytime_expire_interval),
2133 .mode = 0644,
2134 .proc_handler = dirtytime_interval_handler,
2135 .extra1 = SYSCTL_ZERO,
2136 },
2137 {
2138 .procname = "swappiness",
2139 .data = &vm_swappiness,
2140 .maxlen = sizeof(vm_swappiness),
2141 .mode = 0644,
2142 .proc_handler = proc_dointvec_minmax,
2143 .extra1 = SYSCTL_ZERO,
2144 .extra2 = SYSCTL_TWO_HUNDRED,
2145 },
2146 #ifdef CONFIG_NUMA
2147 {
2148 .procname = "numa_stat",
2149 .data = &sysctl_vm_numa_stat,
2150 .maxlen = sizeof(int),
2151 .mode = 0644,
2152 .proc_handler = sysctl_vm_numa_stat_handler,
2153 .extra1 = SYSCTL_ZERO,
2154 .extra2 = SYSCTL_ONE,
2155 },
2156 #endif
2157 #ifdef CONFIG_HUGETLB_PAGE
2158 {
2159 .procname = "nr_hugepages",
2160 .data = NULL,
2161 .maxlen = sizeof(unsigned long),
2162 .mode = 0644,
2163 .proc_handler = hugetlb_sysctl_handler,
2164 },
2165 #ifdef CONFIG_NUMA
2166 {
2167 .procname = "nr_hugepages_mempolicy",
2168 .data = NULL,
2169 .maxlen = sizeof(unsigned long),
2170 .mode = 0644,
2171 .proc_handler = &hugetlb_mempolicy_sysctl_handler,
2172 },
2173 #endif
2174 {
2175 .procname = "hugetlb_shm_group",
2176 .data = &sysctl_hugetlb_shm_group,
2177 .maxlen = sizeof(gid_t),
2178 .mode = 0644,
2179 .proc_handler = proc_dointvec,
2180 },
2181 {
2182 .procname = "nr_overcommit_hugepages",
2183 .data = NULL,
2184 .maxlen = sizeof(unsigned long),
2185 .mode = 0644,
2186 .proc_handler = hugetlb_overcommit_handler,
2187 },
2188 #endif
2189 {
2190 .procname = "lowmem_reserve_ratio",
2191 .data = &sysctl_lowmem_reserve_ratio,
2192 .maxlen = sizeof(sysctl_lowmem_reserve_ratio),
2193 .mode = 0644,
2194 .proc_handler = lowmem_reserve_ratio_sysctl_handler,
2195 },
2196 {
2197 .procname = "drop_caches",
2198 .data = &sysctl_drop_caches,
2199 .maxlen = sizeof(int),
2200 .mode = 0200,
2201 .proc_handler = drop_caches_sysctl_handler,
2202 .extra1 = SYSCTL_ONE,
2203 .extra2 = SYSCTL_FOUR,
2204 },
2205 #ifdef CONFIG_COMPACTION
2206 {
2207 .procname = "compact_memory",
2208 .data = NULL,
2209 .maxlen = sizeof(int),
2210 .mode = 0200,
2211 .proc_handler = sysctl_compaction_handler,
2212 },
2213 {
2214 .procname = "compaction_proactiveness",
2215 .data = &sysctl_compaction_proactiveness,
2216 .maxlen = sizeof(sysctl_compaction_proactiveness),
2217 .mode = 0644,
2218 .proc_handler = compaction_proactiveness_sysctl_handler,
2219 .extra1 = SYSCTL_ZERO,
2220 .extra2 = SYSCTL_ONE_HUNDRED,
2221 },
2222 {
2223 .procname = "extfrag_threshold",
2224 .data = &sysctl_extfrag_threshold,
2225 .maxlen = sizeof(int),
2226 .mode = 0644,
2227 .proc_handler = proc_dointvec_minmax,
2228 .extra1 = SYSCTL_ZERO,
2229 .extra2 = SYSCTL_ONE_THOUSAND,
2230 },
2231 {
2232 .procname = "compact_unevictable_allowed",
2233 .data = &sysctl_compact_unevictable_allowed,
2234 .maxlen = sizeof(int),
2235 .mode = 0644,
2236 .proc_handler = proc_dointvec_minmax_warn_RT_change,
2237 .extra1 = SYSCTL_ZERO,
2238 .extra2 = SYSCTL_ONE,
2239 },
2240
2241 #endif /* CONFIG_COMPACTION */
2242 {
2243 .procname = "min_free_kbytes",
2244 .data = &min_free_kbytes,
2245 .maxlen = sizeof(min_free_kbytes),
2246 .mode = 0644,
2247 .proc_handler = min_free_kbytes_sysctl_handler,
2248 .extra1 = SYSCTL_ZERO,
2249 },
2250 {
2251 .procname = "watermark_boost_factor",
2252 .data = &watermark_boost_factor,
2253 .maxlen = sizeof(watermark_boost_factor),
2254 .mode = 0644,
2255 .proc_handler = proc_dointvec_minmax,
2256 .extra1 = SYSCTL_ZERO,
2257 },
2258 {
2259 .procname = "watermark_scale_factor",
2260 .data = &watermark_scale_factor,
2261 .maxlen = sizeof(watermark_scale_factor),
2262 .mode = 0644,
2263 .proc_handler = watermark_scale_factor_sysctl_handler,
2264 .extra1 = SYSCTL_ONE,
2265 .extra2 = SYSCTL_THREE_THOUSAND,
2266 },
2267 {
2268 .procname = "percpu_pagelist_high_fraction",
2269 .data = &percpu_pagelist_high_fraction,
2270 .maxlen = sizeof(percpu_pagelist_high_fraction),
2271 .mode = 0644,
2272 .proc_handler = percpu_pagelist_high_fraction_sysctl_handler,
2273 .extra1 = SYSCTL_ZERO,
2274 },
2275 {
2276 .procname = "page_lock_unfairness",
2277 .data = &sysctl_page_lock_unfairness,
2278 .maxlen = sizeof(sysctl_page_lock_unfairness),
2279 .mode = 0644,
2280 .proc_handler = proc_dointvec_minmax,
2281 .extra1 = SYSCTL_ZERO,
2282 },
2283 #ifdef CONFIG_MMU
2284 {
2285 .procname = "max_map_count",
2286 .data = &sysctl_max_map_count,
2287 .maxlen = sizeof(sysctl_max_map_count),
2288 .mode = 0644,
2289 .proc_handler = proc_dointvec_minmax,
2290 .extra1 = SYSCTL_ZERO,
2291 },
2292 #else
2293 {
2294 .procname = "nr_trim_pages",
2295 .data = &sysctl_nr_trim_pages,
2296 .maxlen = sizeof(sysctl_nr_trim_pages),
2297 .mode = 0644,
2298 .proc_handler = proc_dointvec_minmax,
2299 .extra1 = SYSCTL_ZERO,
2300 },
2301 #endif
2302 {
2303 .procname = "vfs_cache_pressure",
2304 .data = &sysctl_vfs_cache_pressure,
2305 .maxlen = sizeof(sysctl_vfs_cache_pressure),
2306 .mode = 0644,
2307 .proc_handler = proc_dointvec_minmax,
2308 .extra1 = SYSCTL_ZERO,
2309 },
2310 #if defined(HAVE_ARCH_PICK_MMAP_LAYOUT) || \
2311 defined(CONFIG_ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT)
2312 {
2313 .procname = "legacy_va_layout",
2314 .data = &sysctl_legacy_va_layout,
2315 .maxlen = sizeof(sysctl_legacy_va_layout),
2316 .mode = 0644,
2317 .proc_handler = proc_dointvec_minmax,
2318 .extra1 = SYSCTL_ZERO,
2319 },
2320 #endif
2321 #ifdef CONFIG_NUMA
2322 {
2323 .procname = "zone_reclaim_mode",
2324 .data = &node_reclaim_mode,
2325 .maxlen = sizeof(node_reclaim_mode),
2326 .mode = 0644,
2327 .proc_handler = proc_dointvec_minmax,
2328 .extra1 = SYSCTL_ZERO,
2329 },
2330 {
2331 .procname = "min_unmapped_ratio",
2332 .data = &sysctl_min_unmapped_ratio,
2333 .maxlen = sizeof(sysctl_min_unmapped_ratio),
2334 .mode = 0644,
2335 .proc_handler = sysctl_min_unmapped_ratio_sysctl_handler,
2336 .extra1 = SYSCTL_ZERO,
2337 .extra2 = SYSCTL_ONE_HUNDRED,
2338 },
2339 {
2340 .procname = "min_slab_ratio",
2341 .data = &sysctl_min_slab_ratio,
2342 .maxlen = sizeof(sysctl_min_slab_ratio),
2343 .mode = 0644,
2344 .proc_handler = sysctl_min_slab_ratio_sysctl_handler,
2345 .extra1 = SYSCTL_ZERO,
2346 .extra2 = SYSCTL_ONE_HUNDRED,
2347 },
2348 #endif
2349 #ifdef CONFIG_SMP
2350 {
2351 .procname = "stat_interval",
2352 .data = &sysctl_stat_interval,
2353 .maxlen = sizeof(sysctl_stat_interval),
2354 .mode = 0644,
2355 .proc_handler = proc_dointvec_jiffies,
2356 },
2357 {
2358 .procname = "stat_refresh",
2359 .data = NULL,
2360 .maxlen = 0,
2361 .mode = 0600,
2362 .proc_handler = vmstat_refresh,
2363 },
2364 #endif
2365 #ifdef CONFIG_MMU
2366 {
2367 .procname = "mmap_min_addr",
2368 .data = &dac_mmap_min_addr,
2369 .maxlen = sizeof(unsigned long),
2370 .mode = 0644,
2371 .proc_handler = mmap_min_addr_handler,
2372 },
2373 #endif
2374 #ifdef CONFIG_NUMA
2375 {
2376 .procname = "numa_zonelist_order",
2377 .data = &numa_zonelist_order,
2378 .maxlen = NUMA_ZONELIST_ORDER_LEN,
2379 .mode = 0644,
2380 .proc_handler = numa_zonelist_order_handler,
2381 },
2382 #endif
2383 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
2384 (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
2385 {
2386 .procname = "vdso_enabled",
2387 #ifdef CONFIG_X86_32
2388 .data = &vdso32_enabled,
2389 .maxlen = sizeof(vdso32_enabled),
2390 #else
2391 .data = &vdso_enabled,
2392 .maxlen = sizeof(vdso_enabled),
2393 #endif
2394 .mode = 0644,
2395 .proc_handler = proc_dointvec,
2396 .extra1 = SYSCTL_ZERO,
2397 },
2398 #endif
2399 #ifdef CONFIG_MEMORY_FAILURE
2400 {
2401 .procname = "memory_failure_early_kill",
2402 .data = &sysctl_memory_failure_early_kill,
2403 .maxlen = sizeof(sysctl_memory_failure_early_kill),
2404 .mode = 0644,
2405 .proc_handler = proc_dointvec_minmax,
2406 .extra1 = SYSCTL_ZERO,
2407 .extra2 = SYSCTL_ONE,
2408 },
2409 {
2410 .procname = "memory_failure_recovery",
2411 .data = &sysctl_memory_failure_recovery,
2412 .maxlen = sizeof(sysctl_memory_failure_recovery),
2413 .mode = 0644,
2414 .proc_handler = proc_dointvec_minmax,
2415 .extra1 = SYSCTL_ZERO,
2416 .extra2 = SYSCTL_ONE,
2417 },
2418 #endif
2419 {
2420 .procname = "user_reserve_kbytes",
2421 .data = &sysctl_user_reserve_kbytes,
2422 .maxlen = sizeof(sysctl_user_reserve_kbytes),
2423 .mode = 0644,
2424 .proc_handler = proc_doulongvec_minmax,
2425 },
2426 {
2427 .procname = "admin_reserve_kbytes",
2428 .data = &sysctl_admin_reserve_kbytes,
2429 .maxlen = sizeof(sysctl_admin_reserve_kbytes),
2430 .mode = 0644,
2431 .proc_handler = proc_doulongvec_minmax,
2432 },
2433 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
2434 {
2435 .procname = "mmap_rnd_bits",
2436 .data = &mmap_rnd_bits,
2437 .maxlen = sizeof(mmap_rnd_bits),
2438 .mode = 0600,
2439 .proc_handler = proc_dointvec_minmax,
2440 .extra1 = (void *)&mmap_rnd_bits_min,
2441 .extra2 = (void *)&mmap_rnd_bits_max,
2442 },
2443 #endif
2444 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
2445 {
2446 .procname = "mmap_rnd_compat_bits",
2447 .data = &mmap_rnd_compat_bits,
2448 .maxlen = sizeof(mmap_rnd_compat_bits),
2449 .mode = 0600,
2450 .proc_handler = proc_dointvec_minmax,
2451 .extra1 = (void *)&mmap_rnd_compat_bits_min,
2452 .extra2 = (void *)&mmap_rnd_compat_bits_max,
2453 },
2454 #endif
2455 #ifdef CONFIG_USERFAULTFD
2456 {
2457 .procname = "unprivileged_userfaultfd",
2458 .data = &sysctl_unprivileged_userfaultfd,
2459 .maxlen = sizeof(sysctl_unprivileged_userfaultfd),
2460 .mode = 0644,
2461 .proc_handler = proc_dointvec_minmax,
2462 .extra1 = SYSCTL_ZERO,
2463 .extra2 = SYSCTL_ONE,
2464 },
2465 #endif
2466 { }
2467 };
2468
2469 static struct ctl_table debug_table[] = {
2470 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
2471 {
2472 .procname = "exception-trace",
2473 .data = &show_unhandled_signals,
2474 .maxlen = sizeof(int),
2475 .mode = 0644,
2476 .proc_handler = proc_dointvec
2477 },
2478 #endif
2479 { }
2480 };
2481
2482 static struct ctl_table dev_table[] = {
2483 { }
2484 };
2485
2486 DECLARE_SYSCTL_BASE(kernel, kern_table);
2487 DECLARE_SYSCTL_BASE(vm, vm_table);
2488 DECLARE_SYSCTL_BASE(debug, debug_table);
2489 DECLARE_SYSCTL_BASE(dev, dev_table);
2490
sysctl_init_bases(void)2491 int __init sysctl_init_bases(void)
2492 {
2493 register_sysctl_base(kernel);
2494 register_sysctl_base(vm);
2495 register_sysctl_base(debug);
2496 register_sysctl_base(dev);
2497
2498 return 0;
2499 }
2500 #endif /* CONFIG_SYSCTL */
2501 /*
2502 * No sense putting this after each symbol definition, twice,
2503 * exception granted :-)
2504 */
2505 EXPORT_SYMBOL(proc_dobool);
2506 EXPORT_SYMBOL(proc_dointvec);
2507 EXPORT_SYMBOL(proc_douintvec);
2508 EXPORT_SYMBOL(proc_dointvec_jiffies);
2509 EXPORT_SYMBOL(proc_dointvec_minmax);
2510 EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
2511 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
2512 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
2513 EXPORT_SYMBOL(proc_dostring);
2514 EXPORT_SYMBOL(proc_doulongvec_minmax);
2515 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
2516 EXPORT_SYMBOL(proc_do_large_bitmap);
2517