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