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v5.14.15
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 *  linux/lib/vsprintf.c
   4 *
   5 *  Copyright (C) 1991, 1992  Linus Torvalds
   6 */
   7
   8/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
   9/*
  10 * Wirzenius wrote this portably, Torvalds fucked it up :-)
  11 */
  12
  13/*
  14 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
  15 * - changed to provide snprintf and vsnprintf functions
  16 * So Feb  1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
  17 * - scnprintf and vscnprintf
  18 */
  19
  20#include <stdarg.h>
  21#include <linux/build_bug.h>
  22#include <linux/clk.h>
  23#include <linux/clk-provider.h>
  24#include <linux/errname.h>
  25#include <linux/module.h>	/* for KSYM_SYMBOL_LEN */
  26#include <linux/types.h>
  27#include <linux/string.h>
  28#include <linux/ctype.h>
  29#include <linux/kernel.h>
  30#include <linux/kallsyms.h>
  31#include <linux/math64.h>
  32#include <linux/uaccess.h>
  33#include <linux/ioport.h>
  34#include <linux/dcache.h>
  35#include <linux/cred.h>
  36#include <linux/rtc.h>
  37#include <linux/time.h>
  38#include <linux/uuid.h>
  39#include <linux/of.h>
  40#include <net/addrconf.h>
  41#include <linux/siphash.h>
  42#include <linux/compiler.h>
  43#include <linux/property.h>
  44#ifdef CONFIG_BLOCK
  45#include <linux/blkdev.h>
  46#endif
  47
  48#include "../mm/internal.h"	/* For the trace_print_flags arrays */
  49
  50#include <asm/page.h>		/* for PAGE_SIZE */
 
  51#include <asm/byteorder.h>	/* cpu_to_le16 */
  52
  53#include <linux/string_helpers.h>
  54#include "kstrtox.h"
  55
  56static unsigned long long simple_strntoull(const char *startp, size_t max_chars,
  57					   char **endp, unsigned int base)
  58{
  59	const char *cp;
  60	unsigned long long result = 0ULL;
  61	size_t prefix_chars;
  62	unsigned int rv;
  63
  64	cp = _parse_integer_fixup_radix(startp, &base);
  65	prefix_chars = cp - startp;
  66	if (prefix_chars < max_chars) {
  67		rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars);
  68		/* FIXME */
  69		cp += (rv & ~KSTRTOX_OVERFLOW);
  70	} else {
  71		/* Field too short for prefix + digit, skip over without converting */
  72		cp = startp + max_chars;
  73	}
  74
  75	if (endp)
  76		*endp = (char *)cp;
  77
  78	return result;
  79}
  80
  81/**
  82 * simple_strtoull - convert a string to an unsigned long long
  83 * @cp: The start of the string
  84 * @endp: A pointer to the end of the parsed string will be placed here
  85 * @base: The number base to use
  86 *
  87 * This function has caveats. Please use kstrtoull instead.
  88 */
  89noinline
  90unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
  91{
  92	return simple_strntoull(cp, INT_MAX, endp, base);
 
 
 
 
 
 
 
 
 
 
 
  93}
  94EXPORT_SYMBOL(simple_strtoull);
  95
  96/**
  97 * simple_strtoul - convert a string to an unsigned long
  98 * @cp: The start of the string
  99 * @endp: A pointer to the end of the parsed string will be placed here
 100 * @base: The number base to use
 101 *
 102 * This function has caveats. Please use kstrtoul instead.
 103 */
 104unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
 105{
 106	return simple_strtoull(cp, endp, base);
 107}
 108EXPORT_SYMBOL(simple_strtoul);
 109
 110/**
 111 * simple_strtol - convert a string to a signed long
 112 * @cp: The start of the string
 113 * @endp: A pointer to the end of the parsed string will be placed here
 114 * @base: The number base to use
 115 *
 116 * This function has caveats. Please use kstrtol instead.
 117 */
 118long simple_strtol(const char *cp, char **endp, unsigned int base)
 119{
 120	if (*cp == '-')
 121		return -simple_strtoul(cp + 1, endp, base);
 122
 123	return simple_strtoul(cp, endp, base);
 124}
 125EXPORT_SYMBOL(simple_strtol);
 126
 127static long long simple_strntoll(const char *cp, size_t max_chars, char **endp,
 128				 unsigned int base)
 129{
 130	/*
 131	 * simple_strntoull() safely handles receiving max_chars==0 in the
 132	 * case cp[0] == '-' && max_chars == 1.
 133	 * If max_chars == 0 we can drop through and pass it to simple_strntoull()
 134	 * and the content of *cp is irrelevant.
 135	 */
 136	if (*cp == '-' && max_chars > 0)
 137		return -simple_strntoull(cp + 1, max_chars - 1, endp, base);
 138
 139	return simple_strntoull(cp, max_chars, endp, base);
 140}
 141
 142/**
 143 * simple_strtoll - convert a string to a signed long long
 144 * @cp: The start of the string
 145 * @endp: A pointer to the end of the parsed string will be placed here
 146 * @base: The number base to use
 147 *
 148 * This function has caveats. Please use kstrtoll instead.
 149 */
 150long long simple_strtoll(const char *cp, char **endp, unsigned int base)
 151{
 152	return simple_strntoll(cp, INT_MAX, endp, base);
 
 
 
 153}
 154EXPORT_SYMBOL(simple_strtoll);
 155
 156static noinline_for_stack
 157int skip_atoi(const char **s)
 158{
 159	int i = 0;
 160
 161	do {
 162		i = i*10 + *((*s)++) - '0';
 163	} while (isdigit(**s));
 164
 165	return i;
 166}
 167
 168/*
 169 * Decimal conversion is by far the most typical, and is used for
 170 * /proc and /sys data. This directly impacts e.g. top performance
 171 * with many processes running. We optimize it for speed by emitting
 172 * two characters at a time, using a 200 byte lookup table. This
 173 * roughly halves the number of multiplications compared to computing
 174 * the digits one at a time. Implementation strongly inspired by the
 175 * previous version, which in turn used ideas described at
 176 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
 177 * from the author, Douglas W. Jones).
 178 *
 179 * It turns out there is precisely one 26 bit fixed-point
 180 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
 181 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
 182 * range happens to be somewhat larger (x <= 1073741898), but that's
 183 * irrelevant for our purpose.
 184 *
 185 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
 186 * need a 32x32->64 bit multiply, so we simply use the same constant.
 187 *
 188 * For dividing a number in the range [100, 10^4-1] by 100, there are
 189 * several options. The simplest is (x * 0x147b) >> 19, which is valid
 190 * for all x <= 43698.
 191 */
 192
 193static const u16 decpair[100] = {
 194#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
 195	_( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
 196	_(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
 197	_(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
 198	_(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
 199	_(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
 200	_(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
 201	_(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
 202	_(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
 203	_(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
 204	_(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
 205#undef _
 206};
 207
 208/*
 209 * This will print a single '0' even if r == 0, since we would
 210 * immediately jump to out_r where two 0s would be written but only
 211 * one of them accounted for in buf. This is needed by ip4_string
 212 * below. All other callers pass a non-zero value of r.
 213*/
 214static noinline_for_stack
 215char *put_dec_trunc8(char *buf, unsigned r)
 216{
 217	unsigned q;
 218
 219	/* 1 <= r < 10^8 */
 220	if (r < 100)
 221		goto out_r;
 222
 223	/* 100 <= r < 10^8 */
 224	q = (r * (u64)0x28f5c29) >> 32;
 225	*((u16 *)buf) = decpair[r - 100*q];
 226	buf += 2;
 227
 228	/* 1 <= q < 10^6 */
 229	if (q < 100)
 230		goto out_q;
 231
 232	/*  100 <= q < 10^6 */
 233	r = (q * (u64)0x28f5c29) >> 32;
 234	*((u16 *)buf) = decpair[q - 100*r];
 235	buf += 2;
 236
 237	/* 1 <= r < 10^4 */
 238	if (r < 100)
 239		goto out_r;
 240
 241	/* 100 <= r < 10^4 */
 242	q = (r * 0x147b) >> 19;
 243	*((u16 *)buf) = decpair[r - 100*q];
 244	buf += 2;
 245out_q:
 246	/* 1 <= q < 100 */
 247	r = q;
 248out_r:
 249	/* 1 <= r < 100 */
 250	*((u16 *)buf) = decpair[r];
 251	buf += r < 10 ? 1 : 2;
 252	return buf;
 253}
 254
 255#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
 256static noinline_for_stack
 257char *put_dec_full8(char *buf, unsigned r)
 258{
 259	unsigned q;
 260
 261	/* 0 <= r < 10^8 */
 262	q = (r * (u64)0x28f5c29) >> 32;
 263	*((u16 *)buf) = decpair[r - 100*q];
 264	buf += 2;
 265
 266	/* 0 <= q < 10^6 */
 267	r = (q * (u64)0x28f5c29) >> 32;
 268	*((u16 *)buf) = decpair[q - 100*r];
 269	buf += 2;
 270
 271	/* 0 <= r < 10^4 */
 272	q = (r * 0x147b) >> 19;
 273	*((u16 *)buf) = decpair[r - 100*q];
 274	buf += 2;
 275
 276	/* 0 <= q < 100 */
 277	*((u16 *)buf) = decpair[q];
 278	buf += 2;
 279	return buf;
 280}
 281
 282static noinline_for_stack
 283char *put_dec(char *buf, unsigned long long n)
 284{
 285	if (n >= 100*1000*1000)
 286		buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
 287	/* 1 <= n <= 1.6e11 */
 288	if (n >= 100*1000*1000)
 289		buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
 290	/* 1 <= n < 1e8 */
 291	return put_dec_trunc8(buf, n);
 292}
 293
 294#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
 295
 296static void
 297put_dec_full4(char *buf, unsigned r)
 298{
 299	unsigned q;
 300
 301	/* 0 <= r < 10^4 */
 302	q = (r * 0x147b) >> 19;
 303	*((u16 *)buf) = decpair[r - 100*q];
 304	buf += 2;
 305	/* 0 <= q < 100 */
 306	*((u16 *)buf) = decpair[q];
 307}
 308
 309/*
 310 * Call put_dec_full4 on x % 10000, return x / 10000.
 311 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
 312 * holds for all x < 1,128,869,999.  The largest value this
 313 * helper will ever be asked to convert is 1,125,520,955.
 314 * (second call in the put_dec code, assuming n is all-ones).
 315 */
 316static noinline_for_stack
 317unsigned put_dec_helper4(char *buf, unsigned x)
 318{
 319        uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
 320
 321        put_dec_full4(buf, x - q * 10000);
 322        return q;
 323}
 324
 325/* Based on code by Douglas W. Jones found at
 326 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
 327 * (with permission from the author).
 328 * Performs no 64-bit division and hence should be fast on 32-bit machines.
 329 */
 330static
 331char *put_dec(char *buf, unsigned long long n)
 332{
 333	uint32_t d3, d2, d1, q, h;
 334
 335	if (n < 100*1000*1000)
 336		return put_dec_trunc8(buf, n);
 337
 338	d1  = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
 339	h   = (n >> 32);
 340	d2  = (h      ) & 0xffff;
 341	d3  = (h >> 16); /* implicit "& 0xffff" */
 342
 343	/* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
 344	     = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
 345	q   = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
 346	q = put_dec_helper4(buf, q);
 347
 348	q += 7671 * d3 + 9496 * d2 + 6 * d1;
 349	q = put_dec_helper4(buf+4, q);
 350
 351	q += 4749 * d3 + 42 * d2;
 352	q = put_dec_helper4(buf+8, q);
 353
 354	q += 281 * d3;
 355	buf += 12;
 356	if (q)
 357		buf = put_dec_trunc8(buf, q);
 358	else while (buf[-1] == '0')
 359		--buf;
 360
 361	return buf;
 362}
 363
 364#endif
 365
 366/*
 367 * Convert passed number to decimal string.
 368 * Returns the length of string.  On buffer overflow, returns 0.
 369 *
 370 * If speed is not important, use snprintf(). It's easy to read the code.
 371 */
 372int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
 373{
 374	/* put_dec requires 2-byte alignment of the buffer. */
 375	char tmp[sizeof(num) * 3] __aligned(2);
 376	int idx, len;
 377
 378	/* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
 379	if (num <= 9) {
 380		tmp[0] = '0' + num;
 381		len = 1;
 382	} else {
 383		len = put_dec(tmp, num) - tmp;
 384	}
 385
 386	if (len > size || width > size)
 387		return 0;
 388
 389	if (width > len) {
 390		width = width - len;
 391		for (idx = 0; idx < width; idx++)
 392			buf[idx] = ' ';
 393	} else {
 394		width = 0;
 395	}
 396
 397	for (idx = 0; idx < len; ++idx)
 398		buf[idx + width] = tmp[len - idx - 1];
 399
 400	return len + width;
 401}
 402
 403#define SIGN	1		/* unsigned/signed, must be 1 */
 404#define LEFT	2		/* left justified */
 405#define PLUS	4		/* show plus */
 406#define SPACE	8		/* space if plus */
 407#define ZEROPAD	16		/* pad with zero, must be 16 == '0' - ' ' */
 408#define SMALL	32		/* use lowercase in hex (must be 32 == 0x20) */
 409#define SPECIAL	64		/* prefix hex with "0x", octal with "0" */
 410
 411static_assert(ZEROPAD == ('0' - ' '));
 412static_assert(SMALL == ' ');
 413
 414enum format_type {
 415	FORMAT_TYPE_NONE, /* Just a string part */
 416	FORMAT_TYPE_WIDTH,
 417	FORMAT_TYPE_PRECISION,
 418	FORMAT_TYPE_CHAR,
 419	FORMAT_TYPE_STR,
 420	FORMAT_TYPE_PTR,
 421	FORMAT_TYPE_PERCENT_CHAR,
 422	FORMAT_TYPE_INVALID,
 423	FORMAT_TYPE_LONG_LONG,
 424	FORMAT_TYPE_ULONG,
 425	FORMAT_TYPE_LONG,
 426	FORMAT_TYPE_UBYTE,
 427	FORMAT_TYPE_BYTE,
 428	FORMAT_TYPE_USHORT,
 429	FORMAT_TYPE_SHORT,
 430	FORMAT_TYPE_UINT,
 431	FORMAT_TYPE_INT,
 432	FORMAT_TYPE_SIZE_T,
 433	FORMAT_TYPE_PTRDIFF
 434};
 435
 436struct printf_spec {
 437	unsigned int	type:8;		/* format_type enum */
 438	signed int	field_width:24;	/* width of output field */
 439	unsigned int	flags:8;	/* flags to number() */
 440	unsigned int	base:8;		/* number base, 8, 10 or 16 only */
 441	signed int	precision:16;	/* # of digits/chars */
 442} __packed;
 443static_assert(sizeof(struct printf_spec) == 8);
 444
 445#define FIELD_WIDTH_MAX ((1 << 23) - 1)
 446#define PRECISION_MAX ((1 << 15) - 1)
 447
 448static noinline_for_stack
 449char *number(char *buf, char *end, unsigned long long num,
 450	     struct printf_spec spec)
 451{
 452	/* put_dec requires 2-byte alignment of the buffer. */
 453	char tmp[3 * sizeof(num)] __aligned(2);
 454	char sign;
 455	char locase;
 456	int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 457	int i;
 458	bool is_zero = num == 0LL;
 459	int field_width = spec.field_width;
 460	int precision = spec.precision;
 461
 
 
 462	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
 463	 * produces same digits or (maybe lowercased) letters */
 464	locase = (spec.flags & SMALL);
 465	if (spec.flags & LEFT)
 466		spec.flags &= ~ZEROPAD;
 467	sign = 0;
 468	if (spec.flags & SIGN) {
 469		if ((signed long long)num < 0) {
 470			sign = '-';
 471			num = -(signed long long)num;
 472			field_width--;
 473		} else if (spec.flags & PLUS) {
 474			sign = '+';
 475			field_width--;
 476		} else if (spec.flags & SPACE) {
 477			sign = ' ';
 478			field_width--;
 479		}
 480	}
 481	if (need_pfx) {
 482		if (spec.base == 16)
 483			field_width -= 2;
 484		else if (!is_zero)
 485			field_width--;
 486	}
 487
 488	/* generate full string in tmp[], in reverse order */
 489	i = 0;
 490	if (num < spec.base)
 491		tmp[i++] = hex_asc_upper[num] | locase;
 492	else if (spec.base != 10) { /* 8 or 16 */
 493		int mask = spec.base - 1;
 494		int shift = 3;
 495
 496		if (spec.base == 16)
 497			shift = 4;
 498		do {
 499			tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
 500			num >>= shift;
 501		} while (num);
 502	} else { /* base 10 */
 503		i = put_dec(tmp, num) - tmp;
 504	}
 505
 506	/* printing 100 using %2d gives "100", not "00" */
 507	if (i > precision)
 508		precision = i;
 509	/* leading space padding */
 510	field_width -= precision;
 511	if (!(spec.flags & (ZEROPAD | LEFT))) {
 512		while (--field_width >= 0) {
 513			if (buf < end)
 514				*buf = ' ';
 515			++buf;
 516		}
 517	}
 518	/* sign */
 519	if (sign) {
 520		if (buf < end)
 521			*buf = sign;
 522		++buf;
 523	}
 524	/* "0x" / "0" prefix */
 525	if (need_pfx) {
 526		if (spec.base == 16 || !is_zero) {
 527			if (buf < end)
 528				*buf = '0';
 529			++buf;
 530		}
 531		if (spec.base == 16) {
 532			if (buf < end)
 533				*buf = ('X' | locase);
 534			++buf;
 535		}
 536	}
 537	/* zero or space padding */
 538	if (!(spec.flags & LEFT)) {
 539		char c = ' ' + (spec.flags & ZEROPAD);
 540
 541		while (--field_width >= 0) {
 542			if (buf < end)
 543				*buf = c;
 544			++buf;
 545		}
 546	}
 547	/* hmm even more zero padding? */
 548	while (i <= --precision) {
 549		if (buf < end)
 550			*buf = '0';
 551		++buf;
 552	}
 553	/* actual digits of result */
 554	while (--i >= 0) {
 555		if (buf < end)
 556			*buf = tmp[i];
 557		++buf;
 558	}
 559	/* trailing space padding */
 560	while (--field_width >= 0) {
 561		if (buf < end)
 562			*buf = ' ';
 563		++buf;
 564	}
 565
 566	return buf;
 567}
 568
 569static noinline_for_stack
 570char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
 571{
 572	struct printf_spec spec;
 573
 574	spec.type = FORMAT_TYPE_PTR;
 575	spec.field_width = 2 + 2 * size;	/* 0x + hex */
 576	spec.flags = SPECIAL | SMALL | ZEROPAD;
 577	spec.base = 16;
 578	spec.precision = -1;
 579
 580	return number(buf, end, num, spec);
 581}
 582
 583static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
 584{
 585	size_t size;
 586	if (buf >= end)	/* nowhere to put anything */
 587		return;
 588	size = end - buf;
 589	if (size <= spaces) {
 590		memset(buf, ' ', size);
 591		return;
 592	}
 593	if (len) {
 594		if (len > size - spaces)
 595			len = size - spaces;
 596		memmove(buf + spaces, buf, len);
 597	}
 598	memset(buf, ' ', spaces);
 599}
 600
 601/*
 602 * Handle field width padding for a string.
 603 * @buf: current buffer position
 604 * @n: length of string
 605 * @end: end of output buffer
 606 * @spec: for field width and flags
 607 * Returns: new buffer position after padding.
 608 */
 609static noinline_for_stack
 610char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
 611{
 612	unsigned spaces;
 613
 614	if (likely(n >= spec.field_width))
 615		return buf;
 616	/* we want to pad the sucker */
 617	spaces = spec.field_width - n;
 618	if (!(spec.flags & LEFT)) {
 619		move_right(buf - n, end, n, spaces);
 620		return buf + spaces;
 621	}
 622	while (spaces--) {
 623		if (buf < end)
 624			*buf = ' ';
 625		++buf;
 626	}
 627	return buf;
 628}
 629
 630/* Handle string from a well known address. */
 631static char *string_nocheck(char *buf, char *end, const char *s,
 632			    struct printf_spec spec)
 633{
 634	int len = 0;
 635	int lim = spec.precision;
 
 
 
 636
 637	while (lim--) {
 638		char c = *s++;
 639		if (!c)
 640			break;
 641		if (buf < end)
 642			*buf = c;
 643		++buf;
 644		++len;
 645	}
 646	return widen_string(buf, len, end, spec);
 647}
 648
 649static char *err_ptr(char *buf, char *end, void *ptr,
 650		     struct printf_spec spec)
 651{
 652	int err = PTR_ERR(ptr);
 653	const char *sym = errname(err);
 654
 655	if (sym)
 656		return string_nocheck(buf, end, sym, spec);
 657
 658	/*
 659	 * Somebody passed ERR_PTR(-1234) or some other non-existing
 660	 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to
 661	 * printing it as its decimal representation.
 662	 */
 663	spec.flags |= SIGN;
 664	spec.base = 10;
 665	return number(buf, end, err, spec);
 666}
 667
 668/* Be careful: error messages must fit into the given buffer. */
 669static char *error_string(char *buf, char *end, const char *s,
 670			  struct printf_spec spec)
 671{
 672	/*
 673	 * Hard limit to avoid a completely insane messages. It actually
 674	 * works pretty well because most error messages are in
 675	 * the many pointer format modifiers.
 676	 */
 677	if (spec.precision == -1)
 678		spec.precision = 2 * sizeof(void *);
 679
 680	return string_nocheck(buf, end, s, spec);
 681}
 682
 683/*
 684 * Do not call any complex external code here. Nested printk()/vsprintf()
 685 * might cause infinite loops. Failures might break printk() and would
 686 * be hard to debug.
 687 */
 688static const char *check_pointer_msg(const void *ptr)
 689{
 690	if (!ptr)
 691		return "(null)";
 692
 693	if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
 694		return "(efault)";
 695
 696	return NULL;
 697}
 698
 699static int check_pointer(char **buf, char *end, const void *ptr,
 700			 struct printf_spec spec)
 701{
 702	const char *err_msg;
 703
 704	err_msg = check_pointer_msg(ptr);
 705	if (err_msg) {
 706		*buf = error_string(*buf, end, err_msg, spec);
 707		return -EFAULT;
 708	}
 709
 710	return 0;
 711}
 712
 713static noinline_for_stack
 714char *string(char *buf, char *end, const char *s,
 715	     struct printf_spec spec)
 716{
 717	if (check_pointer(&buf, end, s, spec))
 718		return buf;
 719
 720	return string_nocheck(buf, end, s, spec);
 721}
 722
 723static char *pointer_string(char *buf, char *end,
 724			    const void *ptr,
 725			    struct printf_spec spec)
 726{
 727	spec.base = 16;
 728	spec.flags |= SMALL;
 729	if (spec.field_width == -1) {
 730		spec.field_width = 2 * sizeof(ptr);
 731		spec.flags |= ZEROPAD;
 732	}
 733
 734	return number(buf, end, (unsigned long int)ptr, spec);
 735}
 736
 737/* Make pointers available for printing early in the boot sequence. */
 738static int debug_boot_weak_hash __ro_after_init;
 739
 740static int __init debug_boot_weak_hash_enable(char *str)
 741{
 742	debug_boot_weak_hash = 1;
 743	pr_info("debug_boot_weak_hash enabled\n");
 744	return 0;
 745}
 746early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
 747
 748static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
 749static siphash_key_t ptr_key __read_mostly;
 750
 751static void enable_ptr_key_workfn(struct work_struct *work)
 752{
 753	get_random_bytes(&ptr_key, sizeof(ptr_key));
 754	/* Needs to run from preemptible context */
 755	static_branch_disable(&not_filled_random_ptr_key);
 756}
 757
 758static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
 759
 760static void fill_random_ptr_key(struct random_ready_callback *unused)
 761{
 762	/* This may be in an interrupt handler. */
 763	queue_work(system_unbound_wq, &enable_ptr_key_work);
 764}
 765
 766static struct random_ready_callback random_ready = {
 767	.func = fill_random_ptr_key
 768};
 769
 770static int __init initialize_ptr_random(void)
 771{
 772	int key_size = sizeof(ptr_key);
 773	int ret;
 774
 775	/* Use hw RNG if available. */
 776	if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
 777		static_branch_disable(&not_filled_random_ptr_key);
 778		return 0;
 779	}
 780
 781	ret = add_random_ready_callback(&random_ready);
 782	if (!ret) {
 783		return 0;
 784	} else if (ret == -EALREADY) {
 785		/* This is in preemptible context */
 786		enable_ptr_key_workfn(&enable_ptr_key_work);
 787		return 0;
 788	}
 789
 790	return ret;
 791}
 792early_initcall(initialize_ptr_random);
 793
 794/* Maps a pointer to a 32 bit unique identifier. */
 795static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out)
 796{
 797	unsigned long hashval;
 798
 799	if (static_branch_unlikely(&not_filled_random_ptr_key))
 800		return -EAGAIN;
 801
 802#ifdef CONFIG_64BIT
 803	hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
 804	/*
 805	 * Mask off the first 32 bits, this makes explicit that we have
 806	 * modified the address (and 32 bits is plenty for a unique ID).
 807	 */
 808	hashval = hashval & 0xffffffff;
 809#else
 810	hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
 811#endif
 812	*hashval_out = hashval;
 813	return 0;
 814}
 815
 816int ptr_to_hashval(const void *ptr, unsigned long *hashval_out)
 817{
 818	return __ptr_to_hashval(ptr, hashval_out);
 819}
 820
 821static char *ptr_to_id(char *buf, char *end, const void *ptr,
 822		       struct printf_spec spec)
 823{
 824	const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
 825	unsigned long hashval;
 826	int ret;
 827
 828	/*
 829	 * Print the real pointer value for NULL and error pointers,
 830	 * as they are not actual addresses.
 831	 */
 832	if (IS_ERR_OR_NULL(ptr))
 833		return pointer_string(buf, end, ptr, spec);
 834
 835	/* When debugging early boot use non-cryptographically secure hash. */
 836	if (unlikely(debug_boot_weak_hash)) {
 837		hashval = hash_long((unsigned long)ptr, 32);
 838		return pointer_string(buf, end, (const void *)hashval, spec);
 839	}
 840
 841	ret = __ptr_to_hashval(ptr, &hashval);
 842	if (ret) {
 843		spec.field_width = 2 * sizeof(ptr);
 844		/* string length must be less than default_width */
 845		return error_string(buf, end, str, spec);
 846	}
 847
 848	return pointer_string(buf, end, (const void *)hashval, spec);
 849}
 850
 851int kptr_restrict __read_mostly;
 852
 853static noinline_for_stack
 854char *restricted_pointer(char *buf, char *end, const void *ptr,
 855			 struct printf_spec spec)
 856{
 857	switch (kptr_restrict) {
 858	case 0:
 859		/* Handle as %p, hash and do _not_ leak addresses. */
 860		return ptr_to_id(buf, end, ptr, spec);
 861	case 1: {
 862		const struct cred *cred;
 863
 864		/*
 865		 * kptr_restrict==1 cannot be used in IRQ context
 866		 * because its test for CAP_SYSLOG would be meaningless.
 867		 */
 868		if (in_irq() || in_serving_softirq() || in_nmi()) {
 869			if (spec.field_width == -1)
 870				spec.field_width = 2 * sizeof(ptr);
 871			return error_string(buf, end, "pK-error", spec);
 872		}
 873
 874		/*
 875		 * Only print the real pointer value if the current
 876		 * process has CAP_SYSLOG and is running with the
 877		 * same credentials it started with. This is because
 878		 * access to files is checked at open() time, but %pK
 879		 * checks permission at read() time. We don't want to
 880		 * leak pointer values if a binary opens a file using
 881		 * %pK and then elevates privileges before reading it.
 882		 */
 883		cred = current_cred();
 884		if (!has_capability_noaudit(current, CAP_SYSLOG) ||
 885		    !uid_eq(cred->euid, cred->uid) ||
 886		    !gid_eq(cred->egid, cred->gid))
 887			ptr = NULL;
 888		break;
 889	}
 890	case 2:
 891	default:
 892		/* Always print 0's for %pK */
 893		ptr = NULL;
 894		break;
 895	}
 896
 897	return pointer_string(buf, end, ptr, spec);
 898}
 899
 900static noinline_for_stack
 901char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
 902		  const char *fmt)
 903{
 904	const char *array[4], *s;
 905	const struct dentry *p;
 906	int depth;
 907	int i, n;
 908
 909	switch (fmt[1]) {
 910		case '2': case '3': case '4':
 911			depth = fmt[1] - '0';
 912			break;
 913		default:
 914			depth = 1;
 915	}
 916
 917	rcu_read_lock();
 918	for (i = 0; i < depth; i++, d = p) {
 919		if (check_pointer(&buf, end, d, spec)) {
 920			rcu_read_unlock();
 921			return buf;
 922		}
 923
 924		p = READ_ONCE(d->d_parent);
 925		array[i] = READ_ONCE(d->d_name.name);
 926		if (p == d) {
 927			if (i)
 928				array[i] = "";
 929			i++;
 930			break;
 931		}
 932	}
 933	s = array[--i];
 934	for (n = 0; n != spec.precision; n++, buf++) {
 935		char c = *s++;
 936		if (!c) {
 937			if (!i)
 938				break;
 939			c = '/';
 940			s = array[--i];
 941		}
 942		if (buf < end)
 943			*buf = c;
 944	}
 945	rcu_read_unlock();
 946	return widen_string(buf, n, end, spec);
 947}
 948
 949static noinline_for_stack
 950char *file_dentry_name(char *buf, char *end, const struct file *f,
 951			struct printf_spec spec, const char *fmt)
 952{
 953	if (check_pointer(&buf, end, f, spec))
 954		return buf;
 955
 956	return dentry_name(buf, end, f->f_path.dentry, spec, fmt);
 957}
 958#ifdef CONFIG_BLOCK
 959static noinline_for_stack
 960char *bdev_name(char *buf, char *end, struct block_device *bdev,
 961		struct printf_spec spec, const char *fmt)
 962{
 963	struct gendisk *hd;
 964
 965	if (check_pointer(&buf, end, bdev, spec))
 966		return buf;
 967
 968	hd = bdev->bd_disk;
 969	buf = string(buf, end, hd->disk_name, spec);
 970	if (bdev->bd_partno) {
 971		if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
 972			if (buf < end)
 973				*buf = 'p';
 974			buf++;
 975		}
 976		buf = number(buf, end, bdev->bd_partno, spec);
 977	}
 978	return buf;
 979}
 980#endif
 981
 982static noinline_for_stack
 983char *symbol_string(char *buf, char *end, void *ptr,
 984		    struct printf_spec spec, const char *fmt)
 985{
 986	unsigned long value;
 987#ifdef CONFIG_KALLSYMS
 988	char sym[KSYM_SYMBOL_LEN];
 989#endif
 990
 991	if (fmt[1] == 'R')
 992		ptr = __builtin_extract_return_addr(ptr);
 993	value = (unsigned long)ptr;
 994
 995#ifdef CONFIG_KALLSYMS
 996	if (*fmt == 'B' && fmt[1] == 'b')
 997		sprint_backtrace_build_id(sym, value);
 998	else if (*fmt == 'B')
 999		sprint_backtrace(sym, value);
1000	else if (*fmt == 'S' && (fmt[1] == 'b' || (fmt[1] == 'R' && fmt[2] == 'b')))
1001		sprint_symbol_build_id(sym, value);
1002	else if (*fmt != 's')
1003		sprint_symbol(sym, value);
1004	else
1005		sprint_symbol_no_offset(sym, value);
1006
1007	return string_nocheck(buf, end, sym, spec);
1008#else
1009	return special_hex_number(buf, end, value, sizeof(void *));
1010#endif
1011}
1012
1013static const struct printf_spec default_str_spec = {
1014	.field_width = -1,
1015	.precision = -1,
1016};
1017
1018static const struct printf_spec default_flag_spec = {
1019	.base = 16,
1020	.precision = -1,
1021	.flags = SPECIAL | SMALL,
1022};
1023
1024static const struct printf_spec default_dec_spec = {
1025	.base = 10,
1026	.precision = -1,
1027};
1028
1029static const struct printf_spec default_dec02_spec = {
1030	.base = 10,
1031	.field_width = 2,
1032	.precision = -1,
1033	.flags = ZEROPAD,
1034};
1035
1036static const struct printf_spec default_dec04_spec = {
1037	.base = 10,
1038	.field_width = 4,
1039	.precision = -1,
1040	.flags = ZEROPAD,
1041};
1042
1043static noinline_for_stack
1044char *resource_string(char *buf, char *end, struct resource *res,
1045		      struct printf_spec spec, const char *fmt)
1046{
1047#ifndef IO_RSRC_PRINTK_SIZE
1048#define IO_RSRC_PRINTK_SIZE	6
1049#endif
1050
1051#ifndef MEM_RSRC_PRINTK_SIZE
1052#define MEM_RSRC_PRINTK_SIZE	10
1053#endif
1054	static const struct printf_spec io_spec = {
1055		.base = 16,
1056		.field_width = IO_RSRC_PRINTK_SIZE,
1057		.precision = -1,
1058		.flags = SPECIAL | SMALL | ZEROPAD,
1059	};
1060	static const struct printf_spec mem_spec = {
1061		.base = 16,
1062		.field_width = MEM_RSRC_PRINTK_SIZE,
1063		.precision = -1,
1064		.flags = SPECIAL | SMALL | ZEROPAD,
1065	};
1066	static const struct printf_spec bus_spec = {
1067		.base = 16,
1068		.field_width = 2,
1069		.precision = -1,
1070		.flags = SMALL | ZEROPAD,
1071	};
 
 
 
 
 
1072	static const struct printf_spec str_spec = {
1073		.field_width = -1,
1074		.precision = 10,
1075		.flags = LEFT,
1076	};
 
 
 
 
 
1077
1078	/* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
1079	 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
1080#define RSRC_BUF_SIZE		((2 * sizeof(resource_size_t)) + 4)
1081#define FLAG_BUF_SIZE		(2 * sizeof(res->flags))
1082#define DECODED_BUF_SIZE	sizeof("[mem - 64bit pref window disabled]")
1083#define RAW_BUF_SIZE		sizeof("[mem - flags 0x]")
1084	char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
1085		     2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
1086
1087	char *p = sym, *pend = sym + sizeof(sym);
1088	int decode = (fmt[0] == 'R') ? 1 : 0;
1089	const struct printf_spec *specp;
1090
1091	if (check_pointer(&buf, end, res, spec))
1092		return buf;
1093
1094	*p++ = '[';
1095	if (res->flags & IORESOURCE_IO) {
1096		p = string_nocheck(p, pend, "io  ", str_spec);
1097		specp = &io_spec;
1098	} else if (res->flags & IORESOURCE_MEM) {
1099		p = string_nocheck(p, pend, "mem ", str_spec);
1100		specp = &mem_spec;
1101	} else if (res->flags & IORESOURCE_IRQ) {
1102		p = string_nocheck(p, pend, "irq ", str_spec);
1103		specp = &default_dec_spec;
1104	} else if (res->flags & IORESOURCE_DMA) {
1105		p = string_nocheck(p, pend, "dma ", str_spec);
1106		specp = &default_dec_spec;
1107	} else if (res->flags & IORESOURCE_BUS) {
1108		p = string_nocheck(p, pend, "bus ", str_spec);
1109		specp = &bus_spec;
1110	} else {
1111		p = string_nocheck(p, pend, "??? ", str_spec);
1112		specp = &mem_spec;
1113		decode = 0;
1114	}
1115	if (decode && res->flags & IORESOURCE_UNSET) {
1116		p = string_nocheck(p, pend, "size ", str_spec);
1117		p = number(p, pend, resource_size(res), *specp);
1118	} else {
1119		p = number(p, pend, res->start, *specp);
1120		if (res->start != res->end) {
1121			*p++ = '-';
1122			p = number(p, pend, res->end, *specp);
1123		}
1124	}
1125	if (decode) {
1126		if (res->flags & IORESOURCE_MEM_64)
1127			p = string_nocheck(p, pend, " 64bit", str_spec);
1128		if (res->flags & IORESOURCE_PREFETCH)
1129			p = string_nocheck(p, pend, " pref", str_spec);
1130		if (res->flags & IORESOURCE_WINDOW)
1131			p = string_nocheck(p, pend, " window", str_spec);
1132		if (res->flags & IORESOURCE_DISABLED)
1133			p = string_nocheck(p, pend, " disabled", str_spec);
1134	} else {
1135		p = string_nocheck(p, pend, " flags ", str_spec);
1136		p = number(p, pend, res->flags, default_flag_spec);
1137	}
1138	*p++ = ']';
1139	*p = '\0';
1140
1141	return string_nocheck(buf, end, sym, spec);
1142}
1143
1144static noinline_for_stack
1145char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1146		 const char *fmt)
1147{
1148	int i, len = 1;		/* if we pass '%ph[CDN]', field width remains
1149				   negative value, fallback to the default */
1150	char separator;
1151
1152	if (spec.field_width == 0)
1153		/* nothing to print */
1154		return buf;
1155
1156	if (check_pointer(&buf, end, addr, spec))
1157		return buf;
 
1158
1159	switch (fmt[1]) {
1160	case 'C':
1161		separator = ':';
1162		break;
1163	case 'D':
1164		separator = '-';
1165		break;
1166	case 'N':
1167		separator = 0;
1168		break;
1169	default:
1170		separator = ' ';
1171		break;
1172	}
1173
1174	if (spec.field_width > 0)
1175		len = min_t(int, spec.field_width, 64);
1176
1177	for (i = 0; i < len; ++i) {
1178		if (buf < end)
1179			*buf = hex_asc_hi(addr[i]);
1180		++buf;
1181		if (buf < end)
1182			*buf = hex_asc_lo(addr[i]);
1183		++buf;
1184
1185		if (separator && i != len - 1) {
1186			if (buf < end)
1187				*buf = separator;
1188			++buf;
1189		}
1190	}
1191
1192	return buf;
1193}
1194
1195static noinline_for_stack
1196char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
1197		    struct printf_spec spec, const char *fmt)
1198{
1199	const int CHUNKSZ = 32;
1200	int nr_bits = max_t(int, spec.field_width, 0);
1201	int i, chunksz;
1202	bool first = true;
1203
1204	if (check_pointer(&buf, end, bitmap, spec))
1205		return buf;
1206
1207	/* reused to print numbers */
1208	spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
1209
1210	chunksz = nr_bits & (CHUNKSZ - 1);
1211	if (chunksz == 0)
1212		chunksz = CHUNKSZ;
1213
1214	i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
1215	for (; i >= 0; i -= CHUNKSZ) {
1216		u32 chunkmask, val;
1217		int word, bit;
1218
1219		chunkmask = ((1ULL << chunksz) - 1);
1220		word = i / BITS_PER_LONG;
1221		bit = i % BITS_PER_LONG;
1222		val = (bitmap[word] >> bit) & chunkmask;
1223
1224		if (!first) {
1225			if (buf < end)
1226				*buf = ',';
1227			buf++;
1228		}
1229		first = false;
1230
1231		spec.field_width = DIV_ROUND_UP(chunksz, 4);
1232		buf = number(buf, end, val, spec);
1233
1234		chunksz = CHUNKSZ;
1235	}
1236	return buf;
1237}
1238
1239static noinline_for_stack
1240char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
1241			 struct printf_spec spec, const char *fmt)
1242{
1243	int nr_bits = max_t(int, spec.field_width, 0);
1244	/* current bit is 'cur', most recently seen range is [rbot, rtop] */
1245	int cur, rbot, rtop;
1246	bool first = true;
1247
1248	if (check_pointer(&buf, end, bitmap, spec))
1249		return buf;
1250
1251	rbot = cur = find_first_bit(bitmap, nr_bits);
1252	while (cur < nr_bits) {
1253		rtop = cur;
1254		cur = find_next_bit(bitmap, nr_bits, cur + 1);
1255		if (cur < nr_bits && cur <= rtop + 1)
1256			continue;
1257
1258		if (!first) {
1259			if (buf < end)
1260				*buf = ',';
1261			buf++;
1262		}
1263		first = false;
1264
1265		buf = number(buf, end, rbot, default_dec_spec);
1266		if (rbot < rtop) {
1267			if (buf < end)
1268				*buf = '-';
1269			buf++;
1270
1271			buf = number(buf, end, rtop, default_dec_spec);
1272		}
1273
1274		rbot = cur;
1275	}
1276	return buf;
1277}
1278
1279static noinline_for_stack
1280char *mac_address_string(char *buf, char *end, u8 *addr,
1281			 struct printf_spec spec, const char *fmt)
1282{
1283	char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
1284	char *p = mac_addr;
1285	int i;
1286	char separator;
1287	bool reversed = false;
1288
1289	if (check_pointer(&buf, end, addr, spec))
1290		return buf;
1291
1292	switch (fmt[1]) {
1293	case 'F':
1294		separator = '-';
1295		break;
1296
1297	case 'R':
1298		reversed = true;
1299		fallthrough;
1300
1301	default:
1302		separator = ':';
1303		break;
1304	}
1305
1306	for (i = 0; i < 6; i++) {
1307		if (reversed)
1308			p = hex_byte_pack(p, addr[5 - i]);
1309		else
1310			p = hex_byte_pack(p, addr[i]);
1311
1312		if (fmt[0] == 'M' && i != 5)
1313			*p++ = separator;
1314	}
1315	*p = '\0';
1316
1317	return string_nocheck(buf, end, mac_addr, spec);
1318}
1319
1320static noinline_for_stack
1321char *ip4_string(char *p, const u8 *addr, const char *fmt)
1322{
1323	int i;
1324	bool leading_zeros = (fmt[0] == 'i');
1325	int index;
1326	int step;
1327
1328	switch (fmt[2]) {
1329	case 'h':
1330#ifdef __BIG_ENDIAN
1331		index = 0;
1332		step = 1;
1333#else
1334		index = 3;
1335		step = -1;
1336#endif
1337		break;
1338	case 'l':
1339		index = 3;
1340		step = -1;
1341		break;
1342	case 'n':
1343	case 'b':
1344	default:
1345		index = 0;
1346		step = 1;
1347		break;
1348	}
1349	for (i = 0; i < 4; i++) {
1350		char temp[4] __aligned(2);	/* hold each IP quad in reverse order */
1351		int digits = put_dec_trunc8(temp, addr[index]) - temp;
1352		if (leading_zeros) {
1353			if (digits < 3)
1354				*p++ = '0';
1355			if (digits < 2)
1356				*p++ = '0';
1357		}
1358		/* reverse the digits in the quad */
1359		while (digits--)
1360			*p++ = temp[digits];
1361		if (i < 3)
1362			*p++ = '.';
1363		index += step;
1364	}
1365	*p = '\0';
1366
1367	return p;
1368}
1369
1370static noinline_for_stack
1371char *ip6_compressed_string(char *p, const char *addr)
1372{
1373	int i, j, range;
1374	unsigned char zerolength[8];
1375	int longest = 1;
1376	int colonpos = -1;
1377	u16 word;
1378	u8 hi, lo;
1379	bool needcolon = false;
1380	bool useIPv4;
1381	struct in6_addr in6;
1382
1383	memcpy(&in6, addr, sizeof(struct in6_addr));
1384
1385	useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1386
1387	memset(zerolength, 0, sizeof(zerolength));
1388
1389	if (useIPv4)
1390		range = 6;
1391	else
1392		range = 8;
1393
1394	/* find position of longest 0 run */
1395	for (i = 0; i < range; i++) {
1396		for (j = i; j < range; j++) {
1397			if (in6.s6_addr16[j] != 0)
1398				break;
1399			zerolength[i]++;
1400		}
1401	}
1402	for (i = 0; i < range; i++) {
1403		if (zerolength[i] > longest) {
1404			longest = zerolength[i];
1405			colonpos = i;
1406		}
1407	}
1408	if (longest == 1)		/* don't compress a single 0 */
1409		colonpos = -1;
1410
1411	/* emit address */
1412	for (i = 0; i < range; i++) {
1413		if (i == colonpos) {
1414			if (needcolon || i == 0)
1415				*p++ = ':';
1416			*p++ = ':';
1417			needcolon = false;
1418			i += longest - 1;
1419			continue;
1420		}
1421		if (needcolon) {
1422			*p++ = ':';
1423			needcolon = false;
1424		}
1425		/* hex u16 without leading 0s */
1426		word = ntohs(in6.s6_addr16[i]);
1427		hi = word >> 8;
1428		lo = word & 0xff;
1429		if (hi) {
1430			if (hi > 0x0f)
1431				p = hex_byte_pack(p, hi);
1432			else
1433				*p++ = hex_asc_lo(hi);
1434			p = hex_byte_pack(p, lo);
1435		}
1436		else if (lo > 0x0f)
1437			p = hex_byte_pack(p, lo);
1438		else
1439			*p++ = hex_asc_lo(lo);
1440		needcolon = true;
1441	}
1442
1443	if (useIPv4) {
1444		if (needcolon)
1445			*p++ = ':';
1446		p = ip4_string(p, &in6.s6_addr[12], "I4");
1447	}
1448	*p = '\0';
1449
1450	return p;
1451}
1452
1453static noinline_for_stack
1454char *ip6_string(char *p, const char *addr, const char *fmt)
1455{
1456	int i;
1457
1458	for (i = 0; i < 8; i++) {
1459		p = hex_byte_pack(p, *addr++);
1460		p = hex_byte_pack(p, *addr++);
1461		if (fmt[0] == 'I' && i != 7)
1462			*p++ = ':';
1463	}
1464	*p = '\0';
1465
1466	return p;
1467}
1468
1469static noinline_for_stack
1470char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1471		      struct printf_spec spec, const char *fmt)
1472{
1473	char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1474
1475	if (fmt[0] == 'I' && fmt[2] == 'c')
1476		ip6_compressed_string(ip6_addr, addr);
1477	else
1478		ip6_string(ip6_addr, addr, fmt);
1479
1480	return string_nocheck(buf, end, ip6_addr, spec);
1481}
1482
1483static noinline_for_stack
1484char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1485		      struct printf_spec spec, const char *fmt)
1486{
1487	char ip4_addr[sizeof("255.255.255.255")];
1488
1489	ip4_string(ip4_addr, addr, fmt);
1490
1491	return string_nocheck(buf, end, ip4_addr, spec);
1492}
1493
1494static noinline_for_stack
1495char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1496			 struct printf_spec spec, const char *fmt)
1497{
1498	bool have_p = false, have_s = false, have_f = false, have_c = false;
1499	char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1500		      sizeof(":12345") + sizeof("/123456789") +
1501		      sizeof("%1234567890")];
1502	char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1503	const u8 *addr = (const u8 *) &sa->sin6_addr;
1504	char fmt6[2] = { fmt[0], '6' };
1505	u8 off = 0;
1506
1507	fmt++;
1508	while (isalpha(*++fmt)) {
1509		switch (*fmt) {
1510		case 'p':
1511			have_p = true;
1512			break;
1513		case 'f':
1514			have_f = true;
1515			break;
1516		case 's':
1517			have_s = true;
1518			break;
1519		case 'c':
1520			have_c = true;
1521			break;
1522		}
1523	}
1524
1525	if (have_p || have_s || have_f) {
1526		*p = '[';
1527		off = 1;
1528	}
1529
1530	if (fmt6[0] == 'I' && have_c)
1531		p = ip6_compressed_string(ip6_addr + off, addr);
1532	else
1533		p = ip6_string(ip6_addr + off, addr, fmt6);
1534
1535	if (have_p || have_s || have_f)
1536		*p++ = ']';
1537
1538	if (have_p) {
1539		*p++ = ':';
1540		p = number(p, pend, ntohs(sa->sin6_port), spec);
1541	}
1542	if (have_f) {
1543		*p++ = '/';
1544		p = number(p, pend, ntohl(sa->sin6_flowinfo &
1545					  IPV6_FLOWINFO_MASK), spec);
1546	}
1547	if (have_s) {
1548		*p++ = '%';
1549		p = number(p, pend, sa->sin6_scope_id, spec);
1550	}
1551	*p = '\0';
1552
1553	return string_nocheck(buf, end, ip6_addr, spec);
1554}
1555
1556static noinline_for_stack
1557char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1558			 struct printf_spec spec, const char *fmt)
1559{
1560	bool have_p = false;
1561	char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1562	char *pend = ip4_addr + sizeof(ip4_addr);
1563	const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1564	char fmt4[3] = { fmt[0], '4', 0 };
1565
1566	fmt++;
1567	while (isalpha(*++fmt)) {
1568		switch (*fmt) {
1569		case 'p':
1570			have_p = true;
1571			break;
1572		case 'h':
1573		case 'l':
1574		case 'n':
1575		case 'b':
1576			fmt4[2] = *fmt;
1577			break;
1578		}
1579	}
1580
1581	p = ip4_string(ip4_addr, addr, fmt4);
1582	if (have_p) {
1583		*p++ = ':';
1584		p = number(p, pend, ntohs(sa->sin_port), spec);
1585	}
1586	*p = '\0';
1587
1588	return string_nocheck(buf, end, ip4_addr, spec);
1589}
1590
1591static noinline_for_stack
1592char *ip_addr_string(char *buf, char *end, const void *ptr,
1593		     struct printf_spec spec, const char *fmt)
1594{
1595	char *err_fmt_msg;
1596
1597	if (check_pointer(&buf, end, ptr, spec))
1598		return buf;
1599
1600	switch (fmt[1]) {
1601	case '6':
1602		return ip6_addr_string(buf, end, ptr, spec, fmt);
1603	case '4':
1604		return ip4_addr_string(buf, end, ptr, spec, fmt);
1605	case 'S': {
1606		const union {
1607			struct sockaddr		raw;
1608			struct sockaddr_in	v4;
1609			struct sockaddr_in6	v6;
1610		} *sa = ptr;
1611
1612		switch (sa->raw.sa_family) {
1613		case AF_INET:
1614			return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1615		case AF_INET6:
1616			return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1617		default:
1618			return error_string(buf, end, "(einval)", spec);
1619		}}
1620	}
1621
1622	err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
1623	return error_string(buf, end, err_fmt_msg, spec);
1624}
1625
1626static noinline_for_stack
1627char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1628		     const char *fmt)
1629{
1630	bool found = true;
1631	int count = 1;
1632	unsigned int flags = 0;
1633	int len;
1634
1635	if (spec.field_width == 0)
1636		return buf;				/* nothing to print */
1637
1638	if (check_pointer(&buf, end, addr, spec))
1639		return buf;
 
1640
1641	do {
1642		switch (fmt[count++]) {
1643		case 'a':
1644			flags |= ESCAPE_ANY;
1645			break;
1646		case 'c':
1647			flags |= ESCAPE_SPECIAL;
1648			break;
1649		case 'h':
1650			flags |= ESCAPE_HEX;
1651			break;
1652		case 'n':
1653			flags |= ESCAPE_NULL;
1654			break;
1655		case 'o':
1656			flags |= ESCAPE_OCTAL;
1657			break;
1658		case 'p':
1659			flags |= ESCAPE_NP;
1660			break;
1661		case 's':
1662			flags |= ESCAPE_SPACE;
1663			break;
1664		default:
1665			found = false;
1666			break;
1667		}
1668	} while (found);
1669
1670	if (!flags)
1671		flags = ESCAPE_ANY_NP;
1672
1673	len = spec.field_width < 0 ? 1 : spec.field_width;
1674
1675	/*
1676	 * string_escape_mem() writes as many characters as it can to
1677	 * the given buffer, and returns the total size of the output
1678	 * had the buffer been big enough.
1679	 */
1680	buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1681
1682	return buf;
1683}
1684
1685static char *va_format(char *buf, char *end, struct va_format *va_fmt,
1686		       struct printf_spec spec, const char *fmt)
1687{
1688	va_list va;
1689
1690	if (check_pointer(&buf, end, va_fmt, spec))
1691		return buf;
1692
1693	va_copy(va, *va_fmt->va);
1694	buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
1695	va_end(va);
1696
1697	return buf;
1698}
1699
1700static noinline_for_stack
1701char *uuid_string(char *buf, char *end, const u8 *addr,
1702		  struct printf_spec spec, const char *fmt)
1703{
1704	char uuid[UUID_STRING_LEN + 1];
1705	char *p = uuid;
1706	int i;
1707	const u8 *index = uuid_index;
1708	bool uc = false;
1709
1710	if (check_pointer(&buf, end, addr, spec))
1711		return buf;
1712
1713	switch (*(++fmt)) {
1714	case 'L':
1715		uc = true;
1716		fallthrough;
1717	case 'l':
1718		index = guid_index;
1719		break;
1720	case 'B':
1721		uc = true;
1722		break;
1723	}
1724
1725	for (i = 0; i < 16; i++) {
1726		if (uc)
1727			p = hex_byte_pack_upper(p, addr[index[i]]);
1728		else
1729			p = hex_byte_pack(p, addr[index[i]]);
1730		switch (i) {
1731		case 3:
1732		case 5:
1733		case 7:
1734		case 9:
1735			*p++ = '-';
1736			break;
1737		}
1738	}
1739
1740	*p = 0;
1741
1742	return string_nocheck(buf, end, uuid, spec);
1743}
1744
1745static noinline_for_stack
1746char *netdev_bits(char *buf, char *end, const void *addr,
1747		  struct printf_spec spec,  const char *fmt)
1748{
1749	unsigned long long num;
1750	int size;
1751
1752	if (check_pointer(&buf, end, addr, spec))
1753		return buf;
1754
1755	switch (fmt[1]) {
1756	case 'F':
1757		num = *(const netdev_features_t *)addr;
1758		size = sizeof(netdev_features_t);
1759		break;
1760	default:
1761		return error_string(buf, end, "(%pN?)", spec);
 
 
1762	}
1763
1764	return special_hex_number(buf, end, num, size);
1765}
1766
1767static noinline_for_stack
1768char *fourcc_string(char *buf, char *end, const u32 *fourcc,
1769		    struct printf_spec spec, const char *fmt)
1770{
1771	char output[sizeof("0123 little-endian (0x01234567)")];
1772	char *p = output;
1773	unsigned int i;
1774	u32 val;
1775
1776	if (fmt[1] != 'c' || fmt[2] != 'c')
1777		return error_string(buf, end, "(%p4?)", spec);
1778
1779	if (check_pointer(&buf, end, fourcc, spec))
1780		return buf;
1781
1782	val = *fourcc & ~BIT(31);
1783
1784	for (i = 0; i < sizeof(*fourcc); i++) {
1785		unsigned char c = val >> (i * 8);
1786
1787		/* Print non-control ASCII characters as-is, dot otherwise */
1788		*p++ = isascii(c) && isprint(c) ? c : '.';
1789	}
1790
1791	strcpy(p, *fourcc & BIT(31) ? " big-endian" : " little-endian");
1792	p += strlen(p);
1793
1794	*p++ = ' ';
1795	*p++ = '(';
1796	p = special_hex_number(p, output + sizeof(output) - 2, *fourcc, sizeof(u32));
1797	*p++ = ')';
1798	*p = '\0';
1799
1800	return string(buf, end, output, spec);
1801}
1802
1803static noinline_for_stack
1804char *address_val(char *buf, char *end, const void *addr,
1805		  struct printf_spec spec, const char *fmt)
1806{
1807	unsigned long long num;
1808	int size;
1809
1810	if (check_pointer(&buf, end, addr, spec))
1811		return buf;
1812
1813	switch (fmt[1]) {
1814	case 'd':
1815		num = *(const dma_addr_t *)addr;
1816		size = sizeof(dma_addr_t);
1817		break;
1818	case 'p':
1819	default:
1820		num = *(const phys_addr_t *)addr;
1821		size = sizeof(phys_addr_t);
1822		break;
1823	}
1824
1825	return special_hex_number(buf, end, num, size);
1826}
1827
1828static noinline_for_stack
1829char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1830{
1831	int year = tm->tm_year + (r ? 0 : 1900);
1832	int mon = tm->tm_mon + (r ? 0 : 1);
1833
1834	buf = number(buf, end, year, default_dec04_spec);
1835	if (buf < end)
1836		*buf = '-';
1837	buf++;
1838
1839	buf = number(buf, end, mon, default_dec02_spec);
1840	if (buf < end)
1841		*buf = '-';
1842	buf++;
1843
1844	return number(buf, end, tm->tm_mday, default_dec02_spec);
1845}
1846
1847static noinline_for_stack
1848char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1849{
1850	buf = number(buf, end, tm->tm_hour, default_dec02_spec);
1851	if (buf < end)
1852		*buf = ':';
1853	buf++;
1854
1855	buf = number(buf, end, tm->tm_min, default_dec02_spec);
1856	if (buf < end)
1857		*buf = ':';
1858	buf++;
1859
1860	return number(buf, end, tm->tm_sec, default_dec02_spec);
1861}
1862
1863static noinline_for_stack
1864char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
1865	      struct printf_spec spec, const char *fmt)
1866{
1867	bool have_t = true, have_d = true;
1868	bool raw = false, iso8601_separator = true;
1869	bool found = true;
1870	int count = 2;
1871
1872	if (check_pointer(&buf, end, tm, spec))
1873		return buf;
1874
1875	switch (fmt[count]) {
1876	case 'd':
1877		have_t = false;
1878		count++;
1879		break;
1880	case 't':
1881		have_d = false;
1882		count++;
1883		break;
1884	}
1885
1886	do {
1887		switch (fmt[count++]) {
1888		case 'r':
1889			raw = true;
1890			break;
1891		case 's':
1892			iso8601_separator = false;
1893			break;
1894		default:
1895			found = false;
1896			break;
1897		}
1898	} while (found);
1899
1900	if (have_d)
1901		buf = date_str(buf, end, tm, raw);
1902	if (have_d && have_t) {
1903		if (buf < end)
1904			*buf = iso8601_separator ? 'T' : ' ';
1905		buf++;
1906	}
1907	if (have_t)
1908		buf = time_str(buf, end, tm, raw);
1909
1910	return buf;
1911}
1912
1913static noinline_for_stack
1914char *time64_str(char *buf, char *end, const time64_t time,
1915		 struct printf_spec spec, const char *fmt)
1916{
1917	struct rtc_time rtc_time;
1918	struct tm tm;
1919
1920	time64_to_tm(time, 0, &tm);
1921
1922	rtc_time.tm_sec = tm.tm_sec;
1923	rtc_time.tm_min = tm.tm_min;
1924	rtc_time.tm_hour = tm.tm_hour;
1925	rtc_time.tm_mday = tm.tm_mday;
1926	rtc_time.tm_mon = tm.tm_mon;
1927	rtc_time.tm_year = tm.tm_year;
1928	rtc_time.tm_wday = tm.tm_wday;
1929	rtc_time.tm_yday = tm.tm_yday;
1930
1931	rtc_time.tm_isdst = 0;
1932
1933	return rtc_str(buf, end, &rtc_time, spec, fmt);
1934}
1935
1936static noinline_for_stack
1937char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
1938		    const char *fmt)
1939{
1940	switch (fmt[1]) {
1941	case 'R':
1942		return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
1943	case 'T':
1944		return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt);
1945	default:
1946		return error_string(buf, end, "(%pt?)", spec);
1947	}
1948}
1949
1950static noinline_for_stack
1951char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1952	    const char *fmt)
1953{
1954	if (!IS_ENABLED(CONFIG_HAVE_CLK))
1955		return error_string(buf, end, "(%pC?)", spec);
1956
1957	if (check_pointer(&buf, end, clk, spec))
1958		return buf;
1959
1960	switch (fmt[1]) {
 
 
 
1961	case 'n':
1962	default:
1963#ifdef CONFIG_COMMON_CLK
1964		return string(buf, end, __clk_get_name(clk), spec);
1965#else
1966		return ptr_to_id(buf, end, clk, spec);
1967#endif
1968	}
1969}
1970
1971static
1972char *format_flags(char *buf, char *end, unsigned long flags,
1973					const struct trace_print_flags *names)
1974{
1975	unsigned long mask;
 
 
 
 
 
 
 
 
 
 
1976
1977	for ( ; flags && names->name; names++) {
1978		mask = names->mask;
1979		if ((flags & mask) != mask)
1980			continue;
1981
1982		buf = string(buf, end, names->name, default_str_spec);
1983
1984		flags &= ~mask;
1985		if (flags) {
1986			if (buf < end)
1987				*buf = '|';
1988			buf++;
1989		}
1990	}
1991
1992	if (flags)
1993		buf = number(buf, end, flags, default_flag_spec);
1994
1995	return buf;
1996}
1997
1998struct page_flags_fields {
1999	int width;
2000	int shift;
2001	int mask;
2002	const struct printf_spec *spec;
2003	const char *name;
2004};
2005
2006static const struct page_flags_fields pff[] = {
2007	{SECTIONS_WIDTH, SECTIONS_PGSHIFT, SECTIONS_MASK,
2008	 &default_dec_spec, "section"},
2009	{NODES_WIDTH, NODES_PGSHIFT, NODES_MASK,
2010	 &default_dec_spec, "node"},
2011	{ZONES_WIDTH, ZONES_PGSHIFT, ZONES_MASK,
2012	 &default_dec_spec, "zone"},
2013	{LAST_CPUPID_WIDTH, LAST_CPUPID_PGSHIFT, LAST_CPUPID_MASK,
2014	 &default_flag_spec, "lastcpupid"},
2015	{KASAN_TAG_WIDTH, KASAN_TAG_PGSHIFT, KASAN_TAG_MASK,
2016	 &default_flag_spec, "kasantag"},
2017};
2018
2019static
2020char *format_page_flags(char *buf, char *end, unsigned long flags)
2021{
2022	unsigned long main_flags = flags & (BIT(NR_PAGEFLAGS) - 1);
2023	bool append = false;
2024	int i;
2025
2026	/* Page flags from the main area. */
2027	if (main_flags) {
2028		buf = format_flags(buf, end, main_flags, pageflag_names);
2029		append = true;
2030	}
2031
2032	/* Page flags from the fields area */
2033	for (i = 0; i < ARRAY_SIZE(pff); i++) {
2034		/* Skip undefined fields. */
2035		if (!pff[i].width)
2036			continue;
2037
2038		/* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */
2039		if (append) {
2040			if (buf < end)
2041				*buf = '|';
2042			buf++;
2043		}
2044
2045		buf = string(buf, end, pff[i].name, default_str_spec);
2046		if (buf < end)
2047			*buf = '=';
2048		buf++;
2049		buf = number(buf, end, (flags >> pff[i].shift) & pff[i].mask,
2050			     *pff[i].spec);
2051
2052		append = true;
2053	}
2054
2055	return buf;
2056}
2057
2058static noinline_for_stack
2059char *flags_string(char *buf, char *end, void *flags_ptr,
2060		   struct printf_spec spec, const char *fmt)
2061{
2062	unsigned long flags;
2063	const struct trace_print_flags *names;
2064
2065	if (check_pointer(&buf, end, flags_ptr, spec))
2066		return buf;
2067
2068	switch (fmt[1]) {
2069	case 'p':
2070		return format_page_flags(buf, end, *(unsigned long *)flags_ptr);
 
 
 
 
2071	case 'v':
2072		flags = *(unsigned long *)flags_ptr;
2073		names = vmaflag_names;
2074		break;
2075	case 'g':
2076		flags = (__force unsigned long)(*(gfp_t *)flags_ptr);
2077		names = gfpflag_names;
2078		break;
2079	default:
2080		return error_string(buf, end, "(%pG?)", spec);
2081	}
2082
2083	return format_flags(buf, end, flags, names);
2084}
2085
2086static noinline_for_stack
2087char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf,
2088			      char *end)
2089{
2090	int depth;
2091
2092	/* Loop starting from the root node to the current node. */
2093	for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) {
2094		struct fwnode_handle *__fwnode =
2095			fwnode_get_nth_parent(fwnode, depth);
2096
2097		buf = string(buf, end, fwnode_get_name_prefix(__fwnode),
2098			     default_str_spec);
2099		buf = string(buf, end, fwnode_get_name(__fwnode),
2100			     default_str_spec);
2101
2102		fwnode_handle_put(__fwnode);
2103	}
2104
2105	return buf;
2106}
2107
2108static noinline_for_stack
2109char *device_node_string(char *buf, char *end, struct device_node *dn,
2110			 struct printf_spec spec, const char *fmt)
2111{
2112	char tbuf[sizeof("xxxx") + 1];
2113	const char *p;
2114	int ret;
2115	char *buf_start = buf;
2116	struct property *prop;
2117	bool has_mult, pass;
2118
2119	struct printf_spec str_spec = spec;
2120	str_spec.field_width = -1;
2121
2122	if (fmt[0] != 'F')
2123		return error_string(buf, end, "(%pO?)", spec);
2124
2125	if (!IS_ENABLED(CONFIG_OF))
2126		return error_string(buf, end, "(%pOF?)", spec);
2127
2128	if (check_pointer(&buf, end, dn, spec))
2129		return buf;
2130
2131	/* simple case without anything any more format specifiers */
2132	fmt++;
2133	if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
2134		fmt = "f";
2135
2136	for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
2137		int precision;
2138		if (pass) {
2139			if (buf < end)
2140				*buf = ':';
2141			buf++;
2142		}
2143
2144		switch (*fmt) {
2145		case 'f':	/* full_name */
2146			buf = fwnode_full_name_string(of_fwnode_handle(dn), buf,
2147						      end);
2148			break;
2149		case 'n':	/* name */
2150			p = fwnode_get_name(of_fwnode_handle(dn));
2151			precision = str_spec.precision;
2152			str_spec.precision = strchrnul(p, '@') - p;
2153			buf = string(buf, end, p, str_spec);
2154			str_spec.precision = precision;
2155			break;
2156		case 'p':	/* phandle */
2157			buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec);
2158			break;
2159		case 'P':	/* path-spec */
2160			p = fwnode_get_name(of_fwnode_handle(dn));
2161			if (!p[1])
2162				p = "/";
2163			buf = string(buf, end, p, str_spec);
2164			break;
2165		case 'F':	/* flags */
2166			tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
2167			tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
2168			tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
2169			tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
2170			tbuf[4] = 0;
2171			buf = string_nocheck(buf, end, tbuf, str_spec);
2172			break;
2173		case 'c':	/* major compatible string */
2174			ret = of_property_read_string(dn, "compatible", &p);
2175			if (!ret)
2176				buf = string(buf, end, p, str_spec);
2177			break;
2178		case 'C':	/* full compatible string */
2179			has_mult = false;
2180			of_property_for_each_string(dn, "compatible", prop, p) {
2181				if (has_mult)
2182					buf = string_nocheck(buf, end, ",", str_spec);
2183				buf = string_nocheck(buf, end, "\"", str_spec);
2184				buf = string(buf, end, p, str_spec);
2185				buf = string_nocheck(buf, end, "\"", str_spec);
2186
2187				has_mult = true;
2188			}
2189			break;
2190		default:
2191			break;
2192		}
2193	}
2194
2195	return widen_string(buf, buf - buf_start, end, spec);
2196}
2197
2198static noinline_for_stack
2199char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode,
2200		    struct printf_spec spec, const char *fmt)
2201{
2202	struct printf_spec str_spec = spec;
2203	char *buf_start = buf;
2204
2205	str_spec.field_width = -1;
2206
2207	if (*fmt != 'w')
2208		return error_string(buf, end, "(%pf?)", spec);
2209
2210	if (check_pointer(&buf, end, fwnode, spec))
2211		return buf;
2212
2213	fmt++;
2214
2215	switch (*fmt) {
2216	case 'P':	/* name */
2217		buf = string(buf, end, fwnode_get_name(fwnode), str_spec);
2218		break;
2219	case 'f':	/* full_name */
2220	default:
2221		buf = fwnode_full_name_string(fwnode, buf, end);
2222		break;
2223	}
2224
2225	return widen_string(buf, buf - buf_start, end, spec);
2226}
2227
2228/* Disable pointer hashing if requested */
2229bool no_hash_pointers __ro_after_init;
2230EXPORT_SYMBOL_GPL(no_hash_pointers);
2231
2232int __init no_hash_pointers_enable(char *str)
2233{
2234	if (no_hash_pointers)
2235		return 0;
2236
2237	no_hash_pointers = true;
2238
2239	pr_warn("**********************************************************\n");
2240	pr_warn("**   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **\n");
2241	pr_warn("**                                                      **\n");
2242	pr_warn("** This system shows unhashed kernel memory addresses   **\n");
2243	pr_warn("** via the console, logs, and other interfaces. This    **\n");
2244	pr_warn("** might reduce the security of your system.            **\n");
2245	pr_warn("**                                                      **\n");
2246	pr_warn("** If you see this message and you are not debugging    **\n");
2247	pr_warn("** the kernel, report this immediately to your system   **\n");
2248	pr_warn("** administrator!                                       **\n");
2249	pr_warn("**                                                      **\n");
2250	pr_warn("**   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **\n");
2251	pr_warn("**********************************************************\n");
2252
2253	return 0;
2254}
2255early_param("no_hash_pointers", no_hash_pointers_enable);
2256
2257/*
2258 * Show a '%p' thing.  A kernel extension is that the '%p' is followed
2259 * by an extra set of alphanumeric characters that are extended format
2260 * specifiers.
2261 *
2262 * Please update scripts/checkpatch.pl when adding/removing conversion
2263 * characters.  (Search for "check for vsprintf extension").
2264 *
2265 * Right now we handle:
2266 *
2267 * - 'S' For symbolic direct pointers (or function descriptors) with offset
2268 * - 's' For symbolic direct pointers (or function descriptors) without offset
2269 * - '[Ss]R' as above with __builtin_extract_return_addr() translation
2270 * - 'S[R]b' as above with module build ID (for use in backtraces)
2271 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of
2272 *	    %ps and %pS. Be careful when re-using these specifiers.
2273 * - 'B' For backtraced symbolic direct pointers with offset
2274 * - 'Bb' as above with module build ID (for use in backtraces)
2275 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
2276 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
2277 * - 'b[l]' For a bitmap, the number of bits is determined by the field
2278 *       width which must be explicitly specified either as part of the
2279 *       format string '%32b[l]' or through '%*b[l]', [l] selects
2280 *       range-list format instead of hex format
2281 * - 'M' For a 6-byte MAC address, it prints the address in the
2282 *       usual colon-separated hex notation
2283 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
2284 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
2285 *       with a dash-separated hex notation
2286 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
2287 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
2288 *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
2289 *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
2290 *       [S][pfs]
2291 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2292 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2293 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
2294 *       IPv6 omits the colons (01020304...0f)
2295 *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
2296 *       [S][pfs]
2297 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2298 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2299 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
2300 * - 'I[6S]c' for IPv6 addresses printed as specified by
2301 *       https://tools.ietf.org/html/rfc5952
2302 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
2303 *                of the following flags (see string_escape_mem() for the
2304 *                details):
2305 *                  a - ESCAPE_ANY
2306 *                  c - ESCAPE_SPECIAL
2307 *                  h - ESCAPE_HEX
2308 *                  n - ESCAPE_NULL
2309 *                  o - ESCAPE_OCTAL
2310 *                  p - ESCAPE_NP
2311 *                  s - ESCAPE_SPACE
2312 *                By default ESCAPE_ANY_NP is used.
2313 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
2314 *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
2315 *       Options for %pU are:
2316 *         b big endian lower case hex (default)
2317 *         B big endian UPPER case hex
2318 *         l little endian lower case hex
2319 *         L little endian UPPER case hex
2320 *           big endian output byte order is:
2321 *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
2322 *           little endian output byte order is:
2323 *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
2324 * - 'V' For a struct va_format which contains a format string * and va_list *,
2325 *       call vsnprintf(->format, *->va_list).
2326 *       Implements a "recursive vsnprintf".
2327 *       Do not use this feature without some mechanism to verify the
2328 *       correctness of the format string and va_list arguments.
2329 * - 'K' For a kernel pointer that should be hidden from unprivileged users.
2330 *       Use only for procfs, sysfs and similar files, not printk(); please
2331 *       read the documentation (path below) first.
2332 * - 'NF' For a netdev_features_t
2333 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value.
2334 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
2335 *            a certain separator (' ' by default):
2336 *              C colon
2337 *              D dash
2338 *              N no separator
2339 *            The maximum supported length is 64 bytes of the input. Consider
2340 *            to use print_hex_dump() for the larger input.
2341 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
2342 *           (default assumed to be phys_addr_t, passed by reference)
2343 * - 'd[234]' For a dentry name (optionally 2-4 last components)
2344 * - 'D[234]' Same as 'd' but for a struct file
2345 * - 'g' For block_device name (gendisk + partition number)
2346 * - 't[RT][dt][r][s]' For time and date as represented by:
2347 *      R    struct rtc_time
2348 *      T    time64_t
2349 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
2350 *       (legacy clock framework) of the clock
2351 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
2352 *        (legacy clock framework) of the clock
 
2353 * - 'G' For flags to be printed as a collection of symbolic strings that would
2354 *       construct the specific value. Supported flags given by option:
2355 *       p page flags (see struct page) given as pointer to unsigned long
2356 *       g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
2357 *       v vma flags (VM_*) given as pointer to unsigned long
2358 * - 'OF[fnpPcCF]'  For a device tree object
2359 *                  Without any optional arguments prints the full_name
2360 *                  f device node full_name
2361 *                  n device node name
2362 *                  p device node phandle
2363 *                  P device node path spec (name + @unit)
2364 *                  F device node flags
2365 *                  c major compatible string
2366 *                  C full compatible string
2367 * - 'fw[fP]'	For a firmware node (struct fwnode_handle) pointer
2368 *		Without an option prints the full name of the node
2369 *		f full name
2370 *		P node name, including a possible unit address
2371 * - 'x' For printing the address unmodified. Equivalent to "%lx".
2372 *       Please read the documentation (path below) before using!
2373 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of
2374 *           bpf_trace_printk() where [ku] prefix specifies either kernel (k)
2375 *           or user (u) memory to probe, and:
2376 *              s a string, equivalent to "%s" on direct vsnprintf() use
2377 *
2378 * ** When making changes please also update:
2379 *	Documentation/core-api/printk-formats.rst
2380 *
2381 * Note: The default behaviour (unadorned %p) is to hash the address,
2382 * rendering it useful as a unique identifier.
 
2383 */
2384static noinline_for_stack
2385char *pointer(const char *fmt, char *buf, char *end, void *ptr,
2386	      struct printf_spec spec)
2387{
 
 
 
 
 
 
 
 
 
 
 
 
2388	switch (*fmt) {
 
 
 
 
2389	case 'S':
2390	case 's':
2391		ptr = dereference_symbol_descriptor(ptr);
2392		fallthrough;
2393	case 'B':
2394		return symbol_string(buf, end, ptr, spec, fmt);
2395	case 'R':
2396	case 'r':
2397		return resource_string(buf, end, ptr, spec, fmt);
2398	case 'h':
2399		return hex_string(buf, end, ptr, spec, fmt);
2400	case 'b':
2401		switch (fmt[1]) {
2402		case 'l':
2403			return bitmap_list_string(buf, end, ptr, spec, fmt);
2404		default:
2405			return bitmap_string(buf, end, ptr, spec, fmt);
2406		}
2407	case 'M':			/* Colon separated: 00:01:02:03:04:05 */
2408	case 'm':			/* Contiguous: 000102030405 */
2409					/* [mM]F (FDDI) */
2410					/* [mM]R (Reverse order; Bluetooth) */
2411		return mac_address_string(buf, end, ptr, spec, fmt);
2412	case 'I':			/* Formatted IP supported
2413					 * 4:	1.2.3.4
2414					 * 6:	0001:0203:...:0708
2415					 * 6c:	1::708 or 1::1.2.3.4
2416					 */
2417	case 'i':			/* Contiguous:
2418					 * 4:	001.002.003.004
2419					 * 6:   000102...0f
2420					 */
2421		return ip_addr_string(buf, end, ptr, spec, fmt);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2422	case 'E':
2423		return escaped_string(buf, end, ptr, spec, fmt);
2424	case 'U':
2425		return uuid_string(buf, end, ptr, spec, fmt);
2426	case 'V':
2427		return va_format(buf, end, ptr, spec, fmt);
 
 
 
 
 
 
 
 
2428	case 'K':
2429		return restricted_pointer(buf, end, ptr, spec);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2430	case 'N':
2431		return netdev_bits(buf, end, ptr, spec, fmt);
2432	case '4':
2433		return fourcc_string(buf, end, ptr, spec, fmt);
2434	case 'a':
2435		return address_val(buf, end, ptr, spec, fmt);
2436	case 'd':
2437		return dentry_name(buf, end, ptr, spec, fmt);
2438	case 't':
2439		return time_and_date(buf, end, ptr, spec, fmt);
2440	case 'C':
2441		return clock(buf, end, ptr, spec, fmt);
2442	case 'D':
2443		return file_dentry_name(buf, end, ptr, spec, fmt);
 
 
2444#ifdef CONFIG_BLOCK
2445	case 'g':
2446		return bdev_name(buf, end, ptr, spec, fmt);
2447#endif
2448
2449	case 'G':
2450		return flags_string(buf, end, ptr, spec, fmt);
2451	case 'O':
2452		return device_node_string(buf, end, ptr, spec, fmt + 1);
2453	case 'f':
2454		return fwnode_string(buf, end, ptr, spec, fmt + 1);
2455	case 'x':
2456		return pointer_string(buf, end, ptr, spec);
2457	case 'e':
2458		/* %pe with a non-ERR_PTR gets treated as plain %p */
2459		if (!IS_ERR(ptr))
2460			break;
2461		return err_ptr(buf, end, ptr, spec);
2462	case 'u':
2463	case 'k':
2464		switch (fmt[1]) {
2465		case 's':
2466			return string(buf, end, ptr, spec);
2467		default:
2468			return error_string(buf, end, "(einval)", spec);
2469		}
2470	}
 
2471
2472	/*
2473	 * default is to _not_ leak addresses, so hash before printing,
2474	 * unless no_hash_pointers is specified on the command line.
2475	 */
2476	if (unlikely(no_hash_pointers))
2477		return pointer_string(buf, end, ptr, spec);
2478	else
2479		return ptr_to_id(buf, end, ptr, spec);
2480}
2481
2482/*
2483 * Helper function to decode printf style format.
2484 * Each call decode a token from the format and return the
2485 * number of characters read (or likely the delta where it wants
2486 * to go on the next call).
2487 * The decoded token is returned through the parameters
2488 *
2489 * 'h', 'l', or 'L' for integer fields
2490 * 'z' support added 23/7/1999 S.H.
2491 * 'z' changed to 'Z' --davidm 1/25/99
2492 * 'Z' changed to 'z' --adobriyan 2017-01-25
2493 * 't' added for ptrdiff_t
2494 *
2495 * @fmt: the format string
2496 * @type of the token returned
2497 * @flags: various flags such as +, -, # tokens..
2498 * @field_width: overwritten width
2499 * @base: base of the number (octal, hex, ...)
2500 * @precision: precision of a number
2501 * @qualifier: qualifier of a number (long, size_t, ...)
2502 */
2503static noinline_for_stack
2504int format_decode(const char *fmt, struct printf_spec *spec)
2505{
2506	const char *start = fmt;
2507	char qualifier;
2508
2509	/* we finished early by reading the field width */
2510	if (spec->type == FORMAT_TYPE_WIDTH) {
2511		if (spec->field_width < 0) {
2512			spec->field_width = -spec->field_width;
2513			spec->flags |= LEFT;
2514		}
2515		spec->type = FORMAT_TYPE_NONE;
2516		goto precision;
2517	}
2518
2519	/* we finished early by reading the precision */
2520	if (spec->type == FORMAT_TYPE_PRECISION) {
2521		if (spec->precision < 0)
2522			spec->precision = 0;
2523
2524		spec->type = FORMAT_TYPE_NONE;
2525		goto qualifier;
2526	}
2527
2528	/* By default */
2529	spec->type = FORMAT_TYPE_NONE;
2530
2531	for (; *fmt ; ++fmt) {
2532		if (*fmt == '%')
2533			break;
2534	}
2535
2536	/* Return the current non-format string */
2537	if (fmt != start || !*fmt)
2538		return fmt - start;
2539
2540	/* Process flags */
2541	spec->flags = 0;
2542
2543	while (1) { /* this also skips first '%' */
2544		bool found = true;
2545
2546		++fmt;
2547
2548		switch (*fmt) {
2549		case '-': spec->flags |= LEFT;    break;
2550		case '+': spec->flags |= PLUS;    break;
2551		case ' ': spec->flags |= SPACE;   break;
2552		case '#': spec->flags |= SPECIAL; break;
2553		case '0': spec->flags |= ZEROPAD; break;
2554		default:  found = false;
2555		}
2556
2557		if (!found)
2558			break;
2559	}
2560
2561	/* get field width */
2562	spec->field_width = -1;
2563
2564	if (isdigit(*fmt))
2565		spec->field_width = skip_atoi(&fmt);
2566	else if (*fmt == '*') {
2567		/* it's the next argument */
2568		spec->type = FORMAT_TYPE_WIDTH;
2569		return ++fmt - start;
2570	}
2571
2572precision:
2573	/* get the precision */
2574	spec->precision = -1;
2575	if (*fmt == '.') {
2576		++fmt;
2577		if (isdigit(*fmt)) {
2578			spec->precision = skip_atoi(&fmt);
2579			if (spec->precision < 0)
2580				spec->precision = 0;
2581		} else if (*fmt == '*') {
2582			/* it's the next argument */
2583			spec->type = FORMAT_TYPE_PRECISION;
2584			return ++fmt - start;
2585		}
2586	}
2587
2588qualifier:
2589	/* get the conversion qualifier */
2590	qualifier = 0;
2591	if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2592	    *fmt == 'z' || *fmt == 't') {
2593		qualifier = *fmt++;
2594		if (unlikely(qualifier == *fmt)) {
2595			if (qualifier == 'l') {
2596				qualifier = 'L';
2597				++fmt;
2598			} else if (qualifier == 'h') {
2599				qualifier = 'H';
2600				++fmt;
2601			}
2602		}
2603	}
2604
2605	/* default base */
2606	spec->base = 10;
2607	switch (*fmt) {
2608	case 'c':
2609		spec->type = FORMAT_TYPE_CHAR;
2610		return ++fmt - start;
2611
2612	case 's':
2613		spec->type = FORMAT_TYPE_STR;
2614		return ++fmt - start;
2615
2616	case 'p':
2617		spec->type = FORMAT_TYPE_PTR;
2618		return ++fmt - start;
2619
2620	case '%':
2621		spec->type = FORMAT_TYPE_PERCENT_CHAR;
2622		return ++fmt - start;
2623
2624	/* integer number formats - set up the flags and "break" */
2625	case 'o':
2626		spec->base = 8;
2627		break;
2628
2629	case 'x':
2630		spec->flags |= SMALL;
2631		fallthrough;
2632
2633	case 'X':
2634		spec->base = 16;
2635		break;
2636
2637	case 'd':
2638	case 'i':
2639		spec->flags |= SIGN;
2640		break;
2641	case 'u':
2642		break;
2643
2644	case 'n':
2645		/*
2646		 * Since %n poses a greater security risk than
2647		 * utility, treat it as any other invalid or
2648		 * unsupported format specifier.
2649		 */
2650		fallthrough;
2651
2652	default:
2653		WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2654		spec->type = FORMAT_TYPE_INVALID;
2655		return fmt - start;
2656	}
2657
2658	if (qualifier == 'L')
2659		spec->type = FORMAT_TYPE_LONG_LONG;
2660	else if (qualifier == 'l') {
2661		BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2662		spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2663	} else if (qualifier == 'z') {
2664		spec->type = FORMAT_TYPE_SIZE_T;
2665	} else if (qualifier == 't') {
2666		spec->type = FORMAT_TYPE_PTRDIFF;
2667	} else if (qualifier == 'H') {
2668		BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2669		spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2670	} else if (qualifier == 'h') {
2671		BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2672		spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2673	} else {
2674		BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2675		spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2676	}
2677
2678	return ++fmt - start;
2679}
2680
2681static void
2682set_field_width(struct printf_spec *spec, int width)
2683{
2684	spec->field_width = width;
2685	if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2686		spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2687	}
2688}
2689
2690static void
2691set_precision(struct printf_spec *spec, int prec)
2692{
2693	spec->precision = prec;
2694	if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2695		spec->precision = clamp(prec, 0, PRECISION_MAX);
2696	}
2697}
2698
2699/**
2700 * vsnprintf - Format a string and place it in a buffer
2701 * @buf: The buffer to place the result into
2702 * @size: The size of the buffer, including the trailing null space
2703 * @fmt: The format string to use
2704 * @args: Arguments for the format string
2705 *
2706 * This function generally follows C99 vsnprintf, but has some
2707 * extensions and a few limitations:
2708 *
2709 *  - ``%n`` is unsupported
2710 *  - ``%p*`` is handled by pointer()
2711 *
2712 * See pointer() or Documentation/core-api/printk-formats.rst for more
2713 * extensive description.
2714 *
2715 * **Please update the documentation in both places when making changes**
2716 *
2717 * The return value is the number of characters which would
2718 * be generated for the given input, excluding the trailing
2719 * '\0', as per ISO C99. If you want to have the exact
2720 * number of characters written into @buf as return value
2721 * (not including the trailing '\0'), use vscnprintf(). If the
2722 * return is greater than or equal to @size, the resulting
2723 * string is truncated.
2724 *
2725 * If you're not already dealing with a va_list consider using snprintf().
2726 */
2727int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2728{
2729	unsigned long long num;
2730	char *str, *end;
2731	struct printf_spec spec = {0};
2732
2733	/* Reject out-of-range values early.  Large positive sizes are
2734	   used for unknown buffer sizes. */
2735	if (WARN_ON_ONCE(size > INT_MAX))
2736		return 0;
2737
2738	str = buf;
2739	end = buf + size;
2740
2741	/* Make sure end is always >= buf */
2742	if (end < buf) {
2743		end = ((void *)-1);
2744		size = end - buf;
2745	}
2746
2747	while (*fmt) {
2748		const char *old_fmt = fmt;
2749		int read = format_decode(fmt, &spec);
2750
2751		fmt += read;
2752
2753		switch (spec.type) {
2754		case FORMAT_TYPE_NONE: {
2755			int copy = read;
2756			if (str < end) {
2757				if (copy > end - str)
2758					copy = end - str;
2759				memcpy(str, old_fmt, copy);
2760			}
2761			str += read;
2762			break;
2763		}
2764
2765		case FORMAT_TYPE_WIDTH:
2766			set_field_width(&spec, va_arg(args, int));
2767			break;
2768
2769		case FORMAT_TYPE_PRECISION:
2770			set_precision(&spec, va_arg(args, int));
2771			break;
2772
2773		case FORMAT_TYPE_CHAR: {
2774			char c;
2775
2776			if (!(spec.flags & LEFT)) {
2777				while (--spec.field_width > 0) {
2778					if (str < end)
2779						*str = ' ';
2780					++str;
2781
2782				}
2783			}
2784			c = (unsigned char) va_arg(args, int);
2785			if (str < end)
2786				*str = c;
2787			++str;
2788			while (--spec.field_width > 0) {
2789				if (str < end)
2790					*str = ' ';
2791				++str;
2792			}
2793			break;
2794		}
2795
2796		case FORMAT_TYPE_STR:
2797			str = string(str, end, va_arg(args, char *), spec);
2798			break;
2799
2800		case FORMAT_TYPE_PTR:
2801			str = pointer(fmt, str, end, va_arg(args, void *),
2802				      spec);
2803			while (isalnum(*fmt))
2804				fmt++;
2805			break;
2806
2807		case FORMAT_TYPE_PERCENT_CHAR:
2808			if (str < end)
2809				*str = '%';
2810			++str;
2811			break;
2812
2813		case FORMAT_TYPE_INVALID:
2814			/*
2815			 * Presumably the arguments passed gcc's type
2816			 * checking, but there is no safe or sane way
2817			 * for us to continue parsing the format and
2818			 * fetching from the va_list; the remaining
2819			 * specifiers and arguments would be out of
2820			 * sync.
2821			 */
2822			goto out;
2823
2824		default:
2825			switch (spec.type) {
2826			case FORMAT_TYPE_LONG_LONG:
2827				num = va_arg(args, long long);
2828				break;
2829			case FORMAT_TYPE_ULONG:
2830				num = va_arg(args, unsigned long);
2831				break;
2832			case FORMAT_TYPE_LONG:
2833				num = va_arg(args, long);
2834				break;
2835			case FORMAT_TYPE_SIZE_T:
2836				if (spec.flags & SIGN)
2837					num = va_arg(args, ssize_t);
2838				else
2839					num = va_arg(args, size_t);
2840				break;
2841			case FORMAT_TYPE_PTRDIFF:
2842				num = va_arg(args, ptrdiff_t);
2843				break;
2844			case FORMAT_TYPE_UBYTE:
2845				num = (unsigned char) va_arg(args, int);
2846				break;
2847			case FORMAT_TYPE_BYTE:
2848				num = (signed char) va_arg(args, int);
2849				break;
2850			case FORMAT_TYPE_USHORT:
2851				num = (unsigned short) va_arg(args, int);
2852				break;
2853			case FORMAT_TYPE_SHORT:
2854				num = (short) va_arg(args, int);
2855				break;
2856			case FORMAT_TYPE_INT:
2857				num = (int) va_arg(args, int);
2858				break;
2859			default:
2860				num = va_arg(args, unsigned int);
2861			}
2862
2863			str = number(str, end, num, spec);
2864		}
2865	}
2866
2867out:
2868	if (size > 0) {
2869		if (str < end)
2870			*str = '\0';
2871		else
2872			end[-1] = '\0';
2873	}
2874
2875	/* the trailing null byte doesn't count towards the total */
2876	return str-buf;
2877
2878}
2879EXPORT_SYMBOL(vsnprintf);
2880
2881/**
2882 * vscnprintf - Format a string and place it in a buffer
2883 * @buf: The buffer to place the result into
2884 * @size: The size of the buffer, including the trailing null space
2885 * @fmt: The format string to use
2886 * @args: Arguments for the format string
2887 *
2888 * The return value is the number of characters which have been written into
2889 * the @buf not including the trailing '\0'. If @size is == 0 the function
2890 * returns 0.
2891 *
2892 * If you're not already dealing with a va_list consider using scnprintf().
2893 *
2894 * See the vsnprintf() documentation for format string extensions over C99.
2895 */
2896int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2897{
2898	int i;
2899
2900	i = vsnprintf(buf, size, fmt, args);
2901
2902	if (likely(i < size))
2903		return i;
2904	if (size != 0)
2905		return size - 1;
2906	return 0;
2907}
2908EXPORT_SYMBOL(vscnprintf);
2909
2910/**
2911 * snprintf - Format a string and place it in a buffer
2912 * @buf: The buffer to place the result into
2913 * @size: The size of the buffer, including the trailing null space
2914 * @fmt: The format string to use
2915 * @...: Arguments for the format string
2916 *
2917 * The return value is the number of characters which would be
2918 * generated for the given input, excluding the trailing null,
2919 * as per ISO C99.  If the return is greater than or equal to
2920 * @size, the resulting string is truncated.
2921 *
2922 * See the vsnprintf() documentation for format string extensions over C99.
2923 */
2924int snprintf(char *buf, size_t size, const char *fmt, ...)
2925{
2926	va_list args;
2927	int i;
2928
2929	va_start(args, fmt);
2930	i = vsnprintf(buf, size, fmt, args);
2931	va_end(args);
2932
2933	return i;
2934}
2935EXPORT_SYMBOL(snprintf);
2936
2937/**
2938 * scnprintf - Format a string and place it in a buffer
2939 * @buf: The buffer to place the result into
2940 * @size: The size of the buffer, including the trailing null space
2941 * @fmt: The format string to use
2942 * @...: Arguments for the format string
2943 *
2944 * The return value is the number of characters written into @buf not including
2945 * the trailing '\0'. If @size is == 0 the function returns 0.
2946 */
2947
2948int scnprintf(char *buf, size_t size, const char *fmt, ...)
2949{
2950	va_list args;
2951	int i;
2952
2953	va_start(args, fmt);
2954	i = vscnprintf(buf, size, fmt, args);
2955	va_end(args);
2956
2957	return i;
2958}
2959EXPORT_SYMBOL(scnprintf);
2960
2961/**
2962 * vsprintf - Format a string and place it in a buffer
2963 * @buf: The buffer to place the result into
2964 * @fmt: The format string to use
2965 * @args: Arguments for the format string
2966 *
2967 * The function returns the number of characters written
2968 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2969 * buffer overflows.
2970 *
2971 * If you're not already dealing with a va_list consider using sprintf().
2972 *
2973 * See the vsnprintf() documentation for format string extensions over C99.
2974 */
2975int vsprintf(char *buf, const char *fmt, va_list args)
2976{
2977	return vsnprintf(buf, INT_MAX, fmt, args);
2978}
2979EXPORT_SYMBOL(vsprintf);
2980
2981/**
2982 * sprintf - Format a string and place it in a buffer
2983 * @buf: The buffer to place the result into
2984 * @fmt: The format string to use
2985 * @...: Arguments for the format string
2986 *
2987 * The function returns the number of characters written
2988 * into @buf. Use snprintf() or scnprintf() in order to avoid
2989 * buffer overflows.
2990 *
2991 * See the vsnprintf() documentation for format string extensions over C99.
2992 */
2993int sprintf(char *buf, const char *fmt, ...)
2994{
2995	va_list args;
2996	int i;
2997
2998	va_start(args, fmt);
2999	i = vsnprintf(buf, INT_MAX, fmt, args);
3000	va_end(args);
3001
3002	return i;
3003}
3004EXPORT_SYMBOL(sprintf);
3005
3006#ifdef CONFIG_BINARY_PRINTF
3007/*
3008 * bprintf service:
3009 * vbin_printf() - VA arguments to binary data
3010 * bstr_printf() - Binary data to text string
3011 */
3012
3013/**
3014 * vbin_printf - Parse a format string and place args' binary value in a buffer
3015 * @bin_buf: The buffer to place args' binary value
3016 * @size: The size of the buffer(by words(32bits), not characters)
3017 * @fmt: The format string to use
3018 * @args: Arguments for the format string
3019 *
3020 * The format follows C99 vsnprintf, except %n is ignored, and its argument
3021 * is skipped.
3022 *
3023 * The return value is the number of words(32bits) which would be generated for
3024 * the given input.
3025 *
3026 * NOTE:
3027 * If the return value is greater than @size, the resulting bin_buf is NOT
3028 * valid for bstr_printf().
3029 */
3030int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
3031{
3032	struct printf_spec spec = {0};
3033	char *str, *end;
3034	int width;
3035
3036	str = (char *)bin_buf;
3037	end = (char *)(bin_buf + size);
3038
3039#define save_arg(type)							\
3040({									\
3041	unsigned long long value;					\
3042	if (sizeof(type) == 8) {					\
3043		unsigned long long val8;				\
3044		str = PTR_ALIGN(str, sizeof(u32));			\
3045		val8 = va_arg(args, unsigned long long);		\
3046		if (str + sizeof(type) <= end) {			\
3047			*(u32 *)str = *(u32 *)&val8;			\
3048			*(u32 *)(str + 4) = *((u32 *)&val8 + 1);	\
3049		}							\
3050		value = val8;						\
3051	} else {							\
3052		unsigned int val4;					\
3053		str = PTR_ALIGN(str, sizeof(type));			\
3054		val4 = va_arg(args, int);				\
3055		if (str + sizeof(type) <= end)				\
3056			*(typeof(type) *)str = (type)(long)val4;	\
3057		value = (unsigned long long)val4;			\
3058	}								\
3059	str += sizeof(type);						\
3060	value;								\
3061})
3062
3063	while (*fmt) {
3064		int read = format_decode(fmt, &spec);
3065
3066		fmt += read;
3067
3068		switch (spec.type) {
3069		case FORMAT_TYPE_NONE:
3070		case FORMAT_TYPE_PERCENT_CHAR:
3071			break;
3072		case FORMAT_TYPE_INVALID:
3073			goto out;
3074
3075		case FORMAT_TYPE_WIDTH:
3076		case FORMAT_TYPE_PRECISION:
3077			width = (int)save_arg(int);
3078			/* Pointers may require the width */
3079			if (*fmt == 'p')
3080				set_field_width(&spec, width);
3081			break;
3082
3083		case FORMAT_TYPE_CHAR:
3084			save_arg(char);
3085			break;
3086
3087		case FORMAT_TYPE_STR: {
3088			const char *save_str = va_arg(args, char *);
3089			const char *err_msg;
3090			size_t len;
3091
3092			err_msg = check_pointer_msg(save_str);
3093			if (err_msg)
3094				save_str = err_msg;
3095
3096			len = strlen(save_str) + 1;
3097			if (str + len < end)
3098				memcpy(str, save_str, len);
3099			str += len;
3100			break;
3101		}
3102
3103		case FORMAT_TYPE_PTR:
3104			/* Dereferenced pointers must be done now */
3105			switch (*fmt) {
3106			/* Dereference of functions is still OK */
3107			case 'S':
3108			case 's':
3109			case 'x':
3110			case 'K':
3111			case 'e':
3112				save_arg(void *);
3113				break;
3114			default:
3115				if (!isalnum(*fmt)) {
3116					save_arg(void *);
3117					break;
3118				}
3119				str = pointer(fmt, str, end, va_arg(args, void *),
3120					      spec);
3121				if (str + 1 < end)
3122					*str++ = '\0';
3123				else
3124					end[-1] = '\0'; /* Must be nul terminated */
3125			}
3126			/* skip all alphanumeric pointer suffixes */
3127			while (isalnum(*fmt))
3128				fmt++;
3129			break;
3130
3131		default:
3132			switch (spec.type) {
3133
3134			case FORMAT_TYPE_LONG_LONG:
3135				save_arg(long long);
3136				break;
3137			case FORMAT_TYPE_ULONG:
3138			case FORMAT_TYPE_LONG:
3139				save_arg(unsigned long);
3140				break;
3141			case FORMAT_TYPE_SIZE_T:
3142				save_arg(size_t);
3143				break;
3144			case FORMAT_TYPE_PTRDIFF:
3145				save_arg(ptrdiff_t);
3146				break;
3147			case FORMAT_TYPE_UBYTE:
3148			case FORMAT_TYPE_BYTE:
3149				save_arg(char);
3150				break;
3151			case FORMAT_TYPE_USHORT:
3152			case FORMAT_TYPE_SHORT:
3153				save_arg(short);
3154				break;
3155			default:
3156				save_arg(int);
3157			}
3158		}
3159	}
3160
3161out:
3162	return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
3163#undef save_arg
3164}
3165EXPORT_SYMBOL_GPL(vbin_printf);
3166
3167/**
3168 * bstr_printf - Format a string from binary arguments and place it in a buffer
3169 * @buf: The buffer to place the result into
3170 * @size: The size of the buffer, including the trailing null space
3171 * @fmt: The format string to use
3172 * @bin_buf: Binary arguments for the format string
3173 *
3174 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
3175 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
3176 * a binary buffer that generated by vbin_printf.
3177 *
3178 * The format follows C99 vsnprintf, but has some extensions:
3179 *  see vsnprintf comment for details.
3180 *
3181 * The return value is the number of characters which would
3182 * be generated for the given input, excluding the trailing
3183 * '\0', as per ISO C99. If you want to have the exact
3184 * number of characters written into @buf as return value
3185 * (not including the trailing '\0'), use vscnprintf(). If the
3186 * return is greater than or equal to @size, the resulting
3187 * string is truncated.
3188 */
3189int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
3190{
3191	struct printf_spec spec = {0};
3192	char *str, *end;
3193	const char *args = (const char *)bin_buf;
3194
3195	if (WARN_ON_ONCE(size > INT_MAX))
3196		return 0;
3197
3198	str = buf;
3199	end = buf + size;
3200
3201#define get_arg(type)							\
3202({									\
3203	typeof(type) value;						\
3204	if (sizeof(type) == 8) {					\
3205		args = PTR_ALIGN(args, sizeof(u32));			\
3206		*(u32 *)&value = *(u32 *)args;				\
3207		*((u32 *)&value + 1) = *(u32 *)(args + 4);		\
3208	} else {							\
3209		args = PTR_ALIGN(args, sizeof(type));			\
3210		value = *(typeof(type) *)args;				\
3211	}								\
3212	args += sizeof(type);						\
3213	value;								\
3214})
3215
3216	/* Make sure end is always >= buf */
3217	if (end < buf) {
3218		end = ((void *)-1);
3219		size = end - buf;
3220	}
3221
3222	while (*fmt) {
3223		const char *old_fmt = fmt;
3224		int read = format_decode(fmt, &spec);
3225
3226		fmt += read;
3227
3228		switch (spec.type) {
3229		case FORMAT_TYPE_NONE: {
3230			int copy = read;
3231			if (str < end) {
3232				if (copy > end - str)
3233					copy = end - str;
3234				memcpy(str, old_fmt, copy);
3235			}
3236			str += read;
3237			break;
3238		}
3239
3240		case FORMAT_TYPE_WIDTH:
3241			set_field_width(&spec, get_arg(int));
3242			break;
3243
3244		case FORMAT_TYPE_PRECISION:
3245			set_precision(&spec, get_arg(int));
3246			break;
3247
3248		case FORMAT_TYPE_CHAR: {
3249			char c;
3250
3251			if (!(spec.flags & LEFT)) {
3252				while (--spec.field_width > 0) {
3253					if (str < end)
3254						*str = ' ';
3255					++str;
3256				}
3257			}
3258			c = (unsigned char) get_arg(char);
3259			if (str < end)
3260				*str = c;
3261			++str;
3262			while (--spec.field_width > 0) {
3263				if (str < end)
3264					*str = ' ';
3265				++str;
3266			}
3267			break;
3268		}
3269
3270		case FORMAT_TYPE_STR: {
3271			const char *str_arg = args;
3272			args += strlen(str_arg) + 1;
3273			str = string(str, end, (char *)str_arg, spec);
3274			break;
3275		}
3276
3277		case FORMAT_TYPE_PTR: {
3278			bool process = false;
3279			int copy, len;
3280			/* Non function dereferences were already done */
3281			switch (*fmt) {
3282			case 'S':
3283			case 's':
3284			case 'x':
3285			case 'K':
3286			case 'e':
3287				process = true;
3288				break;
3289			default:
3290				if (!isalnum(*fmt)) {
3291					process = true;
3292					break;
3293				}
3294				/* Pointer dereference was already processed */
3295				if (str < end) {
3296					len = copy = strlen(args);
3297					if (copy > end - str)
3298						copy = end - str;
3299					memcpy(str, args, copy);
3300					str += len;
3301					args += len + 1;
3302				}
3303			}
3304			if (process)
3305				str = pointer(fmt, str, end, get_arg(void *), spec);
3306
3307			while (isalnum(*fmt))
3308				fmt++;
3309			break;
3310		}
3311
3312		case FORMAT_TYPE_PERCENT_CHAR:
3313			if (str < end)
3314				*str = '%';
3315			++str;
3316			break;
3317
3318		case FORMAT_TYPE_INVALID:
3319			goto out;
3320
3321		default: {
3322			unsigned long long num;
3323
3324			switch (spec.type) {
3325
3326			case FORMAT_TYPE_LONG_LONG:
3327				num = get_arg(long long);
3328				break;
3329			case FORMAT_TYPE_ULONG:
3330			case FORMAT_TYPE_LONG:
3331				num = get_arg(unsigned long);
3332				break;
3333			case FORMAT_TYPE_SIZE_T:
3334				num = get_arg(size_t);
3335				break;
3336			case FORMAT_TYPE_PTRDIFF:
3337				num = get_arg(ptrdiff_t);
3338				break;
3339			case FORMAT_TYPE_UBYTE:
3340				num = get_arg(unsigned char);
3341				break;
3342			case FORMAT_TYPE_BYTE:
3343				num = get_arg(signed char);
3344				break;
3345			case FORMAT_TYPE_USHORT:
3346				num = get_arg(unsigned short);
3347				break;
3348			case FORMAT_TYPE_SHORT:
3349				num = get_arg(short);
3350				break;
3351			case FORMAT_TYPE_UINT:
3352				num = get_arg(unsigned int);
3353				break;
3354			default:
3355				num = get_arg(int);
3356			}
3357
3358			str = number(str, end, num, spec);
3359		} /* default: */
3360		} /* switch(spec.type) */
3361	} /* while(*fmt) */
3362
3363out:
3364	if (size > 0) {
3365		if (str < end)
3366			*str = '\0';
3367		else
3368			end[-1] = '\0';
3369	}
3370
3371#undef get_arg
3372
3373	/* the trailing null byte doesn't count towards the total */
3374	return str - buf;
3375}
3376EXPORT_SYMBOL_GPL(bstr_printf);
3377
3378/**
3379 * bprintf - Parse a format string and place args' binary value in a buffer
3380 * @bin_buf: The buffer to place args' binary value
3381 * @size: The size of the buffer(by words(32bits), not characters)
3382 * @fmt: The format string to use
3383 * @...: Arguments for the format string
3384 *
3385 * The function returns the number of words(u32) written
3386 * into @bin_buf.
3387 */
3388int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
3389{
3390	va_list args;
3391	int ret;
3392
3393	va_start(args, fmt);
3394	ret = vbin_printf(bin_buf, size, fmt, args);
3395	va_end(args);
3396
3397	return ret;
3398}
3399EXPORT_SYMBOL_GPL(bprintf);
3400
3401#endif /* CONFIG_BINARY_PRINTF */
3402
3403/**
3404 * vsscanf - Unformat a buffer into a list of arguments
3405 * @buf:	input buffer
3406 * @fmt:	format of buffer
3407 * @args:	arguments
3408 */
3409int vsscanf(const char *buf, const char *fmt, va_list args)
3410{
3411	const char *str = buf;
3412	char *next;
3413	char digit;
3414	int num = 0;
3415	u8 qualifier;
3416	unsigned int base;
3417	union {
3418		long long s;
3419		unsigned long long u;
3420	} val;
3421	s16 field_width;
3422	bool is_sign;
3423
3424	while (*fmt) {
3425		/* skip any white space in format */
3426		/* white space in format matches any amount of
3427		 * white space, including none, in the input.
3428		 */
3429		if (isspace(*fmt)) {
3430			fmt = skip_spaces(++fmt);
3431			str = skip_spaces(str);
3432		}
3433
3434		/* anything that is not a conversion must match exactly */
3435		if (*fmt != '%' && *fmt) {
3436			if (*fmt++ != *str++)
3437				break;
3438			continue;
3439		}
3440
3441		if (!*fmt)
3442			break;
3443		++fmt;
3444
3445		/* skip this conversion.
3446		 * advance both strings to next white space
3447		 */
3448		if (*fmt == '*') {
3449			if (!*str)
3450				break;
3451			while (!isspace(*fmt) && *fmt != '%' && *fmt) {
3452				/* '%*[' not yet supported, invalid format */
3453				if (*fmt == '[')
3454					return num;
3455				fmt++;
3456			}
3457			while (!isspace(*str) && *str)
3458				str++;
3459			continue;
3460		}
3461
3462		/* get field width */
3463		field_width = -1;
3464		if (isdigit(*fmt)) {
3465			field_width = skip_atoi(&fmt);
3466			if (field_width <= 0)
3467				break;
3468		}
3469
3470		/* get conversion qualifier */
3471		qualifier = -1;
3472		if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
3473		    *fmt == 'z') {
3474			qualifier = *fmt++;
3475			if (unlikely(qualifier == *fmt)) {
3476				if (qualifier == 'h') {
3477					qualifier = 'H';
3478					fmt++;
3479				} else if (qualifier == 'l') {
3480					qualifier = 'L';
3481					fmt++;
3482				}
3483			}
3484		}
3485
3486		if (!*fmt)
3487			break;
3488
3489		if (*fmt == 'n') {
3490			/* return number of characters read so far */
3491			*va_arg(args, int *) = str - buf;
3492			++fmt;
3493			continue;
3494		}
3495
3496		if (!*str)
3497			break;
3498
3499		base = 10;
3500		is_sign = false;
3501
3502		switch (*fmt++) {
3503		case 'c':
3504		{
3505			char *s = (char *)va_arg(args, char*);
3506			if (field_width == -1)
3507				field_width = 1;
3508			do {
3509				*s++ = *str++;
3510			} while (--field_width > 0 && *str);
3511			num++;
3512		}
3513		continue;
3514		case 's':
3515		{
3516			char *s = (char *)va_arg(args, char *);
3517			if (field_width == -1)
3518				field_width = SHRT_MAX;
3519			/* first, skip leading white space in buffer */
3520			str = skip_spaces(str);
3521
3522			/* now copy until next white space */
3523			while (*str && !isspace(*str) && field_width--)
3524				*s++ = *str++;
3525			*s = '\0';
3526			num++;
3527		}
3528		continue;
3529		/*
3530		 * Warning: This implementation of the '[' conversion specifier
3531		 * deviates from its glibc counterpart in the following ways:
3532		 * (1) It does NOT support ranges i.e. '-' is NOT a special
3533		 *     character
3534		 * (2) It cannot match the closing bracket ']' itself
3535		 * (3) A field width is required
3536		 * (4) '%*[' (discard matching input) is currently not supported
3537		 *
3538		 * Example usage:
3539		 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3540		 *		buf1, buf2, buf3);
3541		 * if (ret < 3)
3542		 *    // etc..
3543		 */
3544		case '[':
3545		{
3546			char *s = (char *)va_arg(args, char *);
3547			DECLARE_BITMAP(set, 256) = {0};
3548			unsigned int len = 0;
3549			bool negate = (*fmt == '^');
3550
3551			/* field width is required */
3552			if (field_width == -1)
3553				return num;
3554
3555			if (negate)
3556				++fmt;
3557
3558			for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3559				set_bit((u8)*fmt, set);
3560
3561			/* no ']' or no character set found */
3562			if (!*fmt || !len)
3563				return num;
3564			++fmt;
3565
3566			if (negate) {
3567				bitmap_complement(set, set, 256);
3568				/* exclude null '\0' byte */
3569				clear_bit(0, set);
3570			}
3571
3572			/* match must be non-empty */
3573			if (!test_bit((u8)*str, set))
3574				return num;
3575
3576			while (test_bit((u8)*str, set) && field_width--)
3577				*s++ = *str++;
3578			*s = '\0';
3579			++num;
3580		}
3581		continue;
3582		case 'o':
3583			base = 8;
3584			break;
3585		case 'x':
3586		case 'X':
3587			base = 16;
3588			break;
3589		case 'i':
3590			base = 0;
3591			fallthrough;
3592		case 'd':
3593			is_sign = true;
3594			fallthrough;
3595		case 'u':
3596			break;
3597		case '%':
3598			/* looking for '%' in str */
3599			if (*str++ != '%')
3600				return num;
3601			continue;
3602		default:
3603			/* invalid format; stop here */
3604			return num;
3605		}
3606
3607		/* have some sort of integer conversion.
3608		 * first, skip white space in buffer.
3609		 */
3610		str = skip_spaces(str);
3611
3612		digit = *str;
3613		if (is_sign && digit == '-') {
3614			if (field_width == 1)
3615				break;
3616
3617			digit = *(str + 1);
3618		}
3619
3620		if (!digit
3621		    || (base == 16 && !isxdigit(digit))
3622		    || (base == 10 && !isdigit(digit))
3623		    || (base == 8 && (!isdigit(digit) || digit > '7'))
3624		    || (base == 0 && !isdigit(digit)))
3625			break;
3626
3627		if (is_sign)
3628			val.s = simple_strntoll(str,
3629						field_width >= 0 ? field_width : INT_MAX,
3630						&next, base);
3631		else
3632			val.u = simple_strntoull(str,
3633						 field_width >= 0 ? field_width : INT_MAX,
3634						 &next, base);
 
 
 
 
 
 
 
 
 
 
 
 
3635
3636		switch (qualifier) {
3637		case 'H':	/* that's 'hh' in format */
3638			if (is_sign)
3639				*va_arg(args, signed char *) = val.s;
3640			else
3641				*va_arg(args, unsigned char *) = val.u;
3642			break;
3643		case 'h':
3644			if (is_sign)
3645				*va_arg(args, short *) = val.s;
3646			else
3647				*va_arg(args, unsigned short *) = val.u;
3648			break;
3649		case 'l':
3650			if (is_sign)
3651				*va_arg(args, long *) = val.s;
3652			else
3653				*va_arg(args, unsigned long *) = val.u;
3654			break;
3655		case 'L':
3656			if (is_sign)
3657				*va_arg(args, long long *) = val.s;
3658			else
3659				*va_arg(args, unsigned long long *) = val.u;
3660			break;
 
3661		case 'z':
3662			*va_arg(args, size_t *) = val.u;
3663			break;
3664		default:
3665			if (is_sign)
3666				*va_arg(args, int *) = val.s;
3667			else
3668				*va_arg(args, unsigned int *) = val.u;
3669			break;
3670		}
3671		num++;
3672
3673		if (!next)
3674			break;
3675		str = next;
3676	}
3677
3678	return num;
3679}
3680EXPORT_SYMBOL(vsscanf);
3681
3682/**
3683 * sscanf - Unformat a buffer into a list of arguments
3684 * @buf:	input buffer
3685 * @fmt:	formatting of buffer
3686 * @...:	resulting arguments
3687 */
3688int sscanf(const char *buf, const char *fmt, ...)
3689{
3690	va_list args;
3691	int i;
3692
3693	va_start(args, fmt);
3694	i = vsscanf(buf, fmt, args);
3695	va_end(args);
3696
3697	return i;
3698}
3699EXPORT_SYMBOL(sscanf);
v4.10.11
 
   1/*
   2 *  linux/lib/vsprintf.c
   3 *
   4 *  Copyright (C) 1991, 1992  Linus Torvalds
   5 */
   6
   7/* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
   8/*
   9 * Wirzenius wrote this portably, Torvalds fucked it up :-)
  10 */
  11
  12/*
  13 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
  14 * - changed to provide snprintf and vsnprintf functions
  15 * So Feb  1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
  16 * - scnprintf and vscnprintf
  17 */
  18
  19#include <stdarg.h>
 
  20#include <linux/clk.h>
  21#include <linux/clk-provider.h>
 
  22#include <linux/module.h>	/* for KSYM_SYMBOL_LEN */
  23#include <linux/types.h>
  24#include <linux/string.h>
  25#include <linux/ctype.h>
  26#include <linux/kernel.h>
  27#include <linux/kallsyms.h>
  28#include <linux/math64.h>
  29#include <linux/uaccess.h>
  30#include <linux/ioport.h>
  31#include <linux/dcache.h>
  32#include <linux/cred.h>
 
 
  33#include <linux/uuid.h>
 
  34#include <net/addrconf.h>
 
 
 
  35#ifdef CONFIG_BLOCK
  36#include <linux/blkdev.h>
  37#endif
  38
  39#include "../mm/internal.h"	/* For the trace_print_flags arrays */
  40
  41#include <asm/page.h>		/* for PAGE_SIZE */
  42#include <asm/sections.h>	/* for dereference_function_descriptor() */
  43#include <asm/byteorder.h>	/* cpu_to_le16 */
  44
  45#include <linux/string_helpers.h>
  46#include "kstrtox.h"
  47
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  48/**
  49 * simple_strtoull - convert a string to an unsigned long long
  50 * @cp: The start of the string
  51 * @endp: A pointer to the end of the parsed string will be placed here
  52 * @base: The number base to use
  53 *
  54 * This function is obsolete. Please use kstrtoull instead.
  55 */
 
  56unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
  57{
  58	unsigned long long result;
  59	unsigned int rv;
  60
  61	cp = _parse_integer_fixup_radix(cp, &base);
  62	rv = _parse_integer(cp, base, &result);
  63	/* FIXME */
  64	cp += (rv & ~KSTRTOX_OVERFLOW);
  65
  66	if (endp)
  67		*endp = (char *)cp;
  68
  69	return result;
  70}
  71EXPORT_SYMBOL(simple_strtoull);
  72
  73/**
  74 * simple_strtoul - convert a string to an unsigned long
  75 * @cp: The start of the string
  76 * @endp: A pointer to the end of the parsed string will be placed here
  77 * @base: The number base to use
  78 *
  79 * This function is obsolete. Please use kstrtoul instead.
  80 */
  81unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
  82{
  83	return simple_strtoull(cp, endp, base);
  84}
  85EXPORT_SYMBOL(simple_strtoul);
  86
  87/**
  88 * simple_strtol - convert a string to a signed long
  89 * @cp: The start of the string
  90 * @endp: A pointer to the end of the parsed string will be placed here
  91 * @base: The number base to use
  92 *
  93 * This function is obsolete. Please use kstrtol instead.
  94 */
  95long simple_strtol(const char *cp, char **endp, unsigned int base)
  96{
  97	if (*cp == '-')
  98		return -simple_strtoul(cp + 1, endp, base);
  99
 100	return simple_strtoul(cp, endp, base);
 101}
 102EXPORT_SYMBOL(simple_strtol);
 103
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 104/**
 105 * simple_strtoll - convert a string to a signed long long
 106 * @cp: The start of the string
 107 * @endp: A pointer to the end of the parsed string will be placed here
 108 * @base: The number base to use
 109 *
 110 * This function is obsolete. Please use kstrtoll instead.
 111 */
 112long long simple_strtoll(const char *cp, char **endp, unsigned int base)
 113{
 114	if (*cp == '-')
 115		return -simple_strtoull(cp + 1, endp, base);
 116
 117	return simple_strtoull(cp, endp, base);
 118}
 119EXPORT_SYMBOL(simple_strtoll);
 120
 121static noinline_for_stack
 122int skip_atoi(const char **s)
 123{
 124	int i = 0;
 125
 126	do {
 127		i = i*10 + *((*s)++) - '0';
 128	} while (isdigit(**s));
 129
 130	return i;
 131}
 132
 133/*
 134 * Decimal conversion is by far the most typical, and is used for
 135 * /proc and /sys data. This directly impacts e.g. top performance
 136 * with many processes running. We optimize it for speed by emitting
 137 * two characters at a time, using a 200 byte lookup table. This
 138 * roughly halves the number of multiplications compared to computing
 139 * the digits one at a time. Implementation strongly inspired by the
 140 * previous version, which in turn used ideas described at
 141 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
 142 * from the author, Douglas W. Jones).
 143 *
 144 * It turns out there is precisely one 26 bit fixed-point
 145 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
 146 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
 147 * range happens to be somewhat larger (x <= 1073741898), but that's
 148 * irrelevant for our purpose.
 149 *
 150 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
 151 * need a 32x32->64 bit multiply, so we simply use the same constant.
 152 *
 153 * For dividing a number in the range [100, 10^4-1] by 100, there are
 154 * several options. The simplest is (x * 0x147b) >> 19, which is valid
 155 * for all x <= 43698.
 156 */
 157
 158static const u16 decpair[100] = {
 159#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
 160	_( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
 161	_(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
 162	_(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
 163	_(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
 164	_(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
 165	_(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
 166	_(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
 167	_(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
 168	_(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
 169	_(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
 170#undef _
 171};
 172
 173/*
 174 * This will print a single '0' even if r == 0, since we would
 175 * immediately jump to out_r where two 0s would be written but only
 176 * one of them accounted for in buf. This is needed by ip4_string
 177 * below. All other callers pass a non-zero value of r.
 178*/
 179static noinline_for_stack
 180char *put_dec_trunc8(char *buf, unsigned r)
 181{
 182	unsigned q;
 183
 184	/* 1 <= r < 10^8 */
 185	if (r < 100)
 186		goto out_r;
 187
 188	/* 100 <= r < 10^8 */
 189	q = (r * (u64)0x28f5c29) >> 32;
 190	*((u16 *)buf) = decpair[r - 100*q];
 191	buf += 2;
 192
 193	/* 1 <= q < 10^6 */
 194	if (q < 100)
 195		goto out_q;
 196
 197	/*  100 <= q < 10^6 */
 198	r = (q * (u64)0x28f5c29) >> 32;
 199	*((u16 *)buf) = decpair[q - 100*r];
 200	buf += 2;
 201
 202	/* 1 <= r < 10^4 */
 203	if (r < 100)
 204		goto out_r;
 205
 206	/* 100 <= r < 10^4 */
 207	q = (r * 0x147b) >> 19;
 208	*((u16 *)buf) = decpair[r - 100*q];
 209	buf += 2;
 210out_q:
 211	/* 1 <= q < 100 */
 212	r = q;
 213out_r:
 214	/* 1 <= r < 100 */
 215	*((u16 *)buf) = decpair[r];
 216	buf += r < 10 ? 1 : 2;
 217	return buf;
 218}
 219
 220#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
 221static noinline_for_stack
 222char *put_dec_full8(char *buf, unsigned r)
 223{
 224	unsigned q;
 225
 226	/* 0 <= r < 10^8 */
 227	q = (r * (u64)0x28f5c29) >> 32;
 228	*((u16 *)buf) = decpair[r - 100*q];
 229	buf += 2;
 230
 231	/* 0 <= q < 10^6 */
 232	r = (q * (u64)0x28f5c29) >> 32;
 233	*((u16 *)buf) = decpair[q - 100*r];
 234	buf += 2;
 235
 236	/* 0 <= r < 10^4 */
 237	q = (r * 0x147b) >> 19;
 238	*((u16 *)buf) = decpair[r - 100*q];
 239	buf += 2;
 240
 241	/* 0 <= q < 100 */
 242	*((u16 *)buf) = decpair[q];
 243	buf += 2;
 244	return buf;
 245}
 246
 247static noinline_for_stack
 248char *put_dec(char *buf, unsigned long long n)
 249{
 250	if (n >= 100*1000*1000)
 251		buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
 252	/* 1 <= n <= 1.6e11 */
 253	if (n >= 100*1000*1000)
 254		buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
 255	/* 1 <= n < 1e8 */
 256	return put_dec_trunc8(buf, n);
 257}
 258
 259#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
 260
 261static void
 262put_dec_full4(char *buf, unsigned r)
 263{
 264	unsigned q;
 265
 266	/* 0 <= r < 10^4 */
 267	q = (r * 0x147b) >> 19;
 268	*((u16 *)buf) = decpair[r - 100*q];
 269	buf += 2;
 270	/* 0 <= q < 100 */
 271	*((u16 *)buf) = decpair[q];
 272}
 273
 274/*
 275 * Call put_dec_full4 on x % 10000, return x / 10000.
 276 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
 277 * holds for all x < 1,128,869,999.  The largest value this
 278 * helper will ever be asked to convert is 1,125,520,955.
 279 * (second call in the put_dec code, assuming n is all-ones).
 280 */
 281static noinline_for_stack
 282unsigned put_dec_helper4(char *buf, unsigned x)
 283{
 284        uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
 285
 286        put_dec_full4(buf, x - q * 10000);
 287        return q;
 288}
 289
 290/* Based on code by Douglas W. Jones found at
 291 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
 292 * (with permission from the author).
 293 * Performs no 64-bit division and hence should be fast on 32-bit machines.
 294 */
 295static
 296char *put_dec(char *buf, unsigned long long n)
 297{
 298	uint32_t d3, d2, d1, q, h;
 299
 300	if (n < 100*1000*1000)
 301		return put_dec_trunc8(buf, n);
 302
 303	d1  = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
 304	h   = (n >> 32);
 305	d2  = (h      ) & 0xffff;
 306	d3  = (h >> 16); /* implicit "& 0xffff" */
 307
 308	/* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
 309	     = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
 310	q   = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
 311	q = put_dec_helper4(buf, q);
 312
 313	q += 7671 * d3 + 9496 * d2 + 6 * d1;
 314	q = put_dec_helper4(buf+4, q);
 315
 316	q += 4749 * d3 + 42 * d2;
 317	q = put_dec_helper4(buf+8, q);
 318
 319	q += 281 * d3;
 320	buf += 12;
 321	if (q)
 322		buf = put_dec_trunc8(buf, q);
 323	else while (buf[-1] == '0')
 324		--buf;
 325
 326	return buf;
 327}
 328
 329#endif
 330
 331/*
 332 * Convert passed number to decimal string.
 333 * Returns the length of string.  On buffer overflow, returns 0.
 334 *
 335 * If speed is not important, use snprintf(). It's easy to read the code.
 336 */
 337int num_to_str(char *buf, int size, unsigned long long num)
 338{
 339	/* put_dec requires 2-byte alignment of the buffer. */
 340	char tmp[sizeof(num) * 3] __aligned(2);
 341	int idx, len;
 342
 343	/* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
 344	if (num <= 9) {
 345		tmp[0] = '0' + num;
 346		len = 1;
 347	} else {
 348		len = put_dec(tmp, num) - tmp;
 349	}
 350
 351	if (len > size)
 352		return 0;
 
 
 
 
 
 
 
 
 
 353	for (idx = 0; idx < len; ++idx)
 354		buf[idx] = tmp[len - idx - 1];
 355	return len;
 
 356}
 357
 358#define SIGN	1		/* unsigned/signed, must be 1 */
 359#define LEFT	2		/* left justified */
 360#define PLUS	4		/* show plus */
 361#define SPACE	8		/* space if plus */
 362#define ZEROPAD	16		/* pad with zero, must be 16 == '0' - ' ' */
 363#define SMALL	32		/* use lowercase in hex (must be 32 == 0x20) */
 364#define SPECIAL	64		/* prefix hex with "0x", octal with "0" */
 365
 
 
 
 366enum format_type {
 367	FORMAT_TYPE_NONE, /* Just a string part */
 368	FORMAT_TYPE_WIDTH,
 369	FORMAT_TYPE_PRECISION,
 370	FORMAT_TYPE_CHAR,
 371	FORMAT_TYPE_STR,
 372	FORMAT_TYPE_PTR,
 373	FORMAT_TYPE_PERCENT_CHAR,
 374	FORMAT_TYPE_INVALID,
 375	FORMAT_TYPE_LONG_LONG,
 376	FORMAT_TYPE_ULONG,
 377	FORMAT_TYPE_LONG,
 378	FORMAT_TYPE_UBYTE,
 379	FORMAT_TYPE_BYTE,
 380	FORMAT_TYPE_USHORT,
 381	FORMAT_TYPE_SHORT,
 382	FORMAT_TYPE_UINT,
 383	FORMAT_TYPE_INT,
 384	FORMAT_TYPE_SIZE_T,
 385	FORMAT_TYPE_PTRDIFF
 386};
 387
 388struct printf_spec {
 389	unsigned int	type:8;		/* format_type enum */
 390	signed int	field_width:24;	/* width of output field */
 391	unsigned int	flags:8;	/* flags to number() */
 392	unsigned int	base:8;		/* number base, 8, 10 or 16 only */
 393	signed int	precision:16;	/* # of digits/chars */
 394} __packed;
 
 
 395#define FIELD_WIDTH_MAX ((1 << 23) - 1)
 396#define PRECISION_MAX ((1 << 15) - 1)
 397
 398static noinline_for_stack
 399char *number(char *buf, char *end, unsigned long long num,
 400	     struct printf_spec spec)
 401{
 402	/* put_dec requires 2-byte alignment of the buffer. */
 403	char tmp[3 * sizeof(num)] __aligned(2);
 404	char sign;
 405	char locase;
 406	int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 407	int i;
 408	bool is_zero = num == 0LL;
 409	int field_width = spec.field_width;
 410	int precision = spec.precision;
 411
 412	BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
 413
 414	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
 415	 * produces same digits or (maybe lowercased) letters */
 416	locase = (spec.flags & SMALL);
 417	if (spec.flags & LEFT)
 418		spec.flags &= ~ZEROPAD;
 419	sign = 0;
 420	if (spec.flags & SIGN) {
 421		if ((signed long long)num < 0) {
 422			sign = '-';
 423			num = -(signed long long)num;
 424			field_width--;
 425		} else if (spec.flags & PLUS) {
 426			sign = '+';
 427			field_width--;
 428		} else if (spec.flags & SPACE) {
 429			sign = ' ';
 430			field_width--;
 431		}
 432	}
 433	if (need_pfx) {
 434		if (spec.base == 16)
 435			field_width -= 2;
 436		else if (!is_zero)
 437			field_width--;
 438	}
 439
 440	/* generate full string in tmp[], in reverse order */
 441	i = 0;
 442	if (num < spec.base)
 443		tmp[i++] = hex_asc_upper[num] | locase;
 444	else if (spec.base != 10) { /* 8 or 16 */
 445		int mask = spec.base - 1;
 446		int shift = 3;
 447
 448		if (spec.base == 16)
 449			shift = 4;
 450		do {
 451			tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
 452			num >>= shift;
 453		} while (num);
 454	} else { /* base 10 */
 455		i = put_dec(tmp, num) - tmp;
 456	}
 457
 458	/* printing 100 using %2d gives "100", not "00" */
 459	if (i > precision)
 460		precision = i;
 461	/* leading space padding */
 462	field_width -= precision;
 463	if (!(spec.flags & (ZEROPAD | LEFT))) {
 464		while (--field_width >= 0) {
 465			if (buf < end)
 466				*buf = ' ';
 467			++buf;
 468		}
 469	}
 470	/* sign */
 471	if (sign) {
 472		if (buf < end)
 473			*buf = sign;
 474		++buf;
 475	}
 476	/* "0x" / "0" prefix */
 477	if (need_pfx) {
 478		if (spec.base == 16 || !is_zero) {
 479			if (buf < end)
 480				*buf = '0';
 481			++buf;
 482		}
 483		if (spec.base == 16) {
 484			if (buf < end)
 485				*buf = ('X' | locase);
 486			++buf;
 487		}
 488	}
 489	/* zero or space padding */
 490	if (!(spec.flags & LEFT)) {
 491		char c = ' ' + (spec.flags & ZEROPAD);
 492		BUILD_BUG_ON(' ' + ZEROPAD != '0');
 493		while (--field_width >= 0) {
 494			if (buf < end)
 495				*buf = c;
 496			++buf;
 497		}
 498	}
 499	/* hmm even more zero padding? */
 500	while (i <= --precision) {
 501		if (buf < end)
 502			*buf = '0';
 503		++buf;
 504	}
 505	/* actual digits of result */
 506	while (--i >= 0) {
 507		if (buf < end)
 508			*buf = tmp[i];
 509		++buf;
 510	}
 511	/* trailing space padding */
 512	while (--field_width >= 0) {
 513		if (buf < end)
 514			*buf = ' ';
 515		++buf;
 516	}
 517
 518	return buf;
 519}
 520
 521static noinline_for_stack
 522char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
 523{
 524	struct printf_spec spec;
 525
 526	spec.type = FORMAT_TYPE_PTR;
 527	spec.field_width = 2 + 2 * size;	/* 0x + hex */
 528	spec.flags = SPECIAL | SMALL | ZEROPAD;
 529	spec.base = 16;
 530	spec.precision = -1;
 531
 532	return number(buf, end, num, spec);
 533}
 534
 535static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
 536{
 537	size_t size;
 538	if (buf >= end)	/* nowhere to put anything */
 539		return;
 540	size = end - buf;
 541	if (size <= spaces) {
 542		memset(buf, ' ', size);
 543		return;
 544	}
 545	if (len) {
 546		if (len > size - spaces)
 547			len = size - spaces;
 548		memmove(buf + spaces, buf, len);
 549	}
 550	memset(buf, ' ', spaces);
 551}
 552
 553/*
 554 * Handle field width padding for a string.
 555 * @buf: current buffer position
 556 * @n: length of string
 557 * @end: end of output buffer
 558 * @spec: for field width and flags
 559 * Returns: new buffer position after padding.
 560 */
 561static noinline_for_stack
 562char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
 563{
 564	unsigned spaces;
 565
 566	if (likely(n >= spec.field_width))
 567		return buf;
 568	/* we want to pad the sucker */
 569	spaces = spec.field_width - n;
 570	if (!(spec.flags & LEFT)) {
 571		move_right(buf - n, end, n, spaces);
 572		return buf + spaces;
 573	}
 574	while (spaces--) {
 575		if (buf < end)
 576			*buf = ' ';
 577		++buf;
 578	}
 579	return buf;
 580}
 581
 582static noinline_for_stack
 583char *string(char *buf, char *end, const char *s, struct printf_spec spec)
 
 584{
 585	int len = 0;
 586	size_t lim = spec.precision;
 587
 588	if ((unsigned long)s < PAGE_SIZE)
 589		s = "(null)";
 590
 591	while (lim--) {
 592		char c = *s++;
 593		if (!c)
 594			break;
 595		if (buf < end)
 596			*buf = c;
 597		++buf;
 598		++len;
 599	}
 600	return widen_string(buf, len, end, spec);
 601}
 602
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 603static noinline_for_stack
 604char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
 605		  const char *fmt)
 606{
 607	const char *array[4], *s;
 608	const struct dentry *p;
 609	int depth;
 610	int i, n;
 611
 612	switch (fmt[1]) {
 613		case '2': case '3': case '4':
 614			depth = fmt[1] - '0';
 615			break;
 616		default:
 617			depth = 1;
 618	}
 619
 620	rcu_read_lock();
 621	for (i = 0; i < depth; i++, d = p) {
 622		p = ACCESS_ONCE(d->d_parent);
 623		array[i] = ACCESS_ONCE(d->d_name.name);
 
 
 
 
 
 624		if (p == d) {
 625			if (i)
 626				array[i] = "";
 627			i++;
 628			break;
 629		}
 630	}
 631	s = array[--i];
 632	for (n = 0; n != spec.precision; n++, buf++) {
 633		char c = *s++;
 634		if (!c) {
 635			if (!i)
 636				break;
 637			c = '/';
 638			s = array[--i];
 639		}
 640		if (buf < end)
 641			*buf = c;
 642	}
 643	rcu_read_unlock();
 644	return widen_string(buf, n, end, spec);
 645}
 646
 
 
 
 
 
 
 
 
 
 647#ifdef CONFIG_BLOCK
 648static noinline_for_stack
 649char *bdev_name(char *buf, char *end, struct block_device *bdev,
 650		struct printf_spec spec, const char *fmt)
 651{
 652	struct gendisk *hd = bdev->bd_disk;
 653	
 
 
 
 
 654	buf = string(buf, end, hd->disk_name, spec);
 655	if (bdev->bd_part->partno) {
 656		if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
 657			if (buf < end)
 658				*buf = 'p';
 659			buf++;
 660		}
 661		buf = number(buf, end, bdev->bd_part->partno, spec);
 662	}
 663	return buf;
 664}
 665#endif
 666
 667static noinline_for_stack
 668char *symbol_string(char *buf, char *end, void *ptr,
 669		    struct printf_spec spec, const char *fmt)
 670{
 671	unsigned long value;
 672#ifdef CONFIG_KALLSYMS
 673	char sym[KSYM_SYMBOL_LEN];
 674#endif
 675
 676	if (fmt[1] == 'R')
 677		ptr = __builtin_extract_return_addr(ptr);
 678	value = (unsigned long)ptr;
 679
 680#ifdef CONFIG_KALLSYMS
 681	if (*fmt == 'B')
 
 
 682		sprint_backtrace(sym, value);
 683	else if (*fmt != 'f' && *fmt != 's')
 
 
 684		sprint_symbol(sym, value);
 685	else
 686		sprint_symbol_no_offset(sym, value);
 687
 688	return string(buf, end, sym, spec);
 689#else
 690	return special_hex_number(buf, end, value, sizeof(void *));
 691#endif
 692}
 693
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 694static noinline_for_stack
 695char *resource_string(char *buf, char *end, struct resource *res,
 696		      struct printf_spec spec, const char *fmt)
 697{
 698#ifndef IO_RSRC_PRINTK_SIZE
 699#define IO_RSRC_PRINTK_SIZE	6
 700#endif
 701
 702#ifndef MEM_RSRC_PRINTK_SIZE
 703#define MEM_RSRC_PRINTK_SIZE	10
 704#endif
 705	static const struct printf_spec io_spec = {
 706		.base = 16,
 707		.field_width = IO_RSRC_PRINTK_SIZE,
 708		.precision = -1,
 709		.flags = SPECIAL | SMALL | ZEROPAD,
 710	};
 711	static const struct printf_spec mem_spec = {
 712		.base = 16,
 713		.field_width = MEM_RSRC_PRINTK_SIZE,
 714		.precision = -1,
 715		.flags = SPECIAL | SMALL | ZEROPAD,
 716	};
 717	static const struct printf_spec bus_spec = {
 718		.base = 16,
 719		.field_width = 2,
 720		.precision = -1,
 721		.flags = SMALL | ZEROPAD,
 722	};
 723	static const struct printf_spec dec_spec = {
 724		.base = 10,
 725		.precision = -1,
 726		.flags = 0,
 727	};
 728	static const struct printf_spec str_spec = {
 729		.field_width = -1,
 730		.precision = 10,
 731		.flags = LEFT,
 732	};
 733	static const struct printf_spec flag_spec = {
 734		.base = 16,
 735		.precision = -1,
 736		.flags = SPECIAL | SMALL,
 737	};
 738
 739	/* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
 740	 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
 741#define RSRC_BUF_SIZE		((2 * sizeof(resource_size_t)) + 4)
 742#define FLAG_BUF_SIZE		(2 * sizeof(res->flags))
 743#define DECODED_BUF_SIZE	sizeof("[mem - 64bit pref window disabled]")
 744#define RAW_BUF_SIZE		sizeof("[mem - flags 0x]")
 745	char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
 746		     2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
 747
 748	char *p = sym, *pend = sym + sizeof(sym);
 749	int decode = (fmt[0] == 'R') ? 1 : 0;
 750	const struct printf_spec *specp;
 751
 
 
 
 752	*p++ = '[';
 753	if (res->flags & IORESOURCE_IO) {
 754		p = string(p, pend, "io  ", str_spec);
 755		specp = &io_spec;
 756	} else if (res->flags & IORESOURCE_MEM) {
 757		p = string(p, pend, "mem ", str_spec);
 758		specp = &mem_spec;
 759	} else if (res->flags & IORESOURCE_IRQ) {
 760		p = string(p, pend, "irq ", str_spec);
 761		specp = &dec_spec;
 762	} else if (res->flags & IORESOURCE_DMA) {
 763		p = string(p, pend, "dma ", str_spec);
 764		specp = &dec_spec;
 765	} else if (res->flags & IORESOURCE_BUS) {
 766		p = string(p, pend, "bus ", str_spec);
 767		specp = &bus_spec;
 768	} else {
 769		p = string(p, pend, "??? ", str_spec);
 770		specp = &mem_spec;
 771		decode = 0;
 772	}
 773	if (decode && res->flags & IORESOURCE_UNSET) {
 774		p = string(p, pend, "size ", str_spec);
 775		p = number(p, pend, resource_size(res), *specp);
 776	} else {
 777		p = number(p, pend, res->start, *specp);
 778		if (res->start != res->end) {
 779			*p++ = '-';
 780			p = number(p, pend, res->end, *specp);
 781		}
 782	}
 783	if (decode) {
 784		if (res->flags & IORESOURCE_MEM_64)
 785			p = string(p, pend, " 64bit", str_spec);
 786		if (res->flags & IORESOURCE_PREFETCH)
 787			p = string(p, pend, " pref", str_spec);
 788		if (res->flags & IORESOURCE_WINDOW)
 789			p = string(p, pend, " window", str_spec);
 790		if (res->flags & IORESOURCE_DISABLED)
 791			p = string(p, pend, " disabled", str_spec);
 792	} else {
 793		p = string(p, pend, " flags ", str_spec);
 794		p = number(p, pend, res->flags, flag_spec);
 795	}
 796	*p++ = ']';
 797	*p = '\0';
 798
 799	return string(buf, end, sym, spec);
 800}
 801
 802static noinline_for_stack
 803char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
 804		 const char *fmt)
 805{
 806	int i, len = 1;		/* if we pass '%ph[CDN]', field width remains
 807				   negative value, fallback to the default */
 808	char separator;
 809
 810	if (spec.field_width == 0)
 811		/* nothing to print */
 812		return buf;
 813
 814	if (ZERO_OR_NULL_PTR(addr))
 815		/* NULL pointer */
 816		return string(buf, end, NULL, spec);
 817
 818	switch (fmt[1]) {
 819	case 'C':
 820		separator = ':';
 821		break;
 822	case 'D':
 823		separator = '-';
 824		break;
 825	case 'N':
 826		separator = 0;
 827		break;
 828	default:
 829		separator = ' ';
 830		break;
 831	}
 832
 833	if (spec.field_width > 0)
 834		len = min_t(int, spec.field_width, 64);
 835
 836	for (i = 0; i < len; ++i) {
 837		if (buf < end)
 838			*buf = hex_asc_hi(addr[i]);
 839		++buf;
 840		if (buf < end)
 841			*buf = hex_asc_lo(addr[i]);
 842		++buf;
 843
 844		if (separator && i != len - 1) {
 845			if (buf < end)
 846				*buf = separator;
 847			++buf;
 848		}
 849	}
 850
 851	return buf;
 852}
 853
 854static noinline_for_stack
 855char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
 856		    struct printf_spec spec, const char *fmt)
 857{
 858	const int CHUNKSZ = 32;
 859	int nr_bits = max_t(int, spec.field_width, 0);
 860	int i, chunksz;
 861	bool first = true;
 862
 
 
 
 863	/* reused to print numbers */
 864	spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
 865
 866	chunksz = nr_bits & (CHUNKSZ - 1);
 867	if (chunksz == 0)
 868		chunksz = CHUNKSZ;
 869
 870	i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
 871	for (; i >= 0; i -= CHUNKSZ) {
 872		u32 chunkmask, val;
 873		int word, bit;
 874
 875		chunkmask = ((1ULL << chunksz) - 1);
 876		word = i / BITS_PER_LONG;
 877		bit = i % BITS_PER_LONG;
 878		val = (bitmap[word] >> bit) & chunkmask;
 879
 880		if (!first) {
 881			if (buf < end)
 882				*buf = ',';
 883			buf++;
 884		}
 885		first = false;
 886
 887		spec.field_width = DIV_ROUND_UP(chunksz, 4);
 888		buf = number(buf, end, val, spec);
 889
 890		chunksz = CHUNKSZ;
 891	}
 892	return buf;
 893}
 894
 895static noinline_for_stack
 896char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
 897			 struct printf_spec spec, const char *fmt)
 898{
 899	int nr_bits = max_t(int, spec.field_width, 0);
 900	/* current bit is 'cur', most recently seen range is [rbot, rtop] */
 901	int cur, rbot, rtop;
 902	bool first = true;
 903
 904	/* reused to print numbers */
 905	spec = (struct printf_spec){ .base = 10 };
 906
 907	rbot = cur = find_first_bit(bitmap, nr_bits);
 908	while (cur < nr_bits) {
 909		rtop = cur;
 910		cur = find_next_bit(bitmap, nr_bits, cur + 1);
 911		if (cur < nr_bits && cur <= rtop + 1)
 912			continue;
 913
 914		if (!first) {
 915			if (buf < end)
 916				*buf = ',';
 917			buf++;
 918		}
 919		first = false;
 920
 921		buf = number(buf, end, rbot, spec);
 922		if (rbot < rtop) {
 923			if (buf < end)
 924				*buf = '-';
 925			buf++;
 926
 927			buf = number(buf, end, rtop, spec);
 928		}
 929
 930		rbot = cur;
 931	}
 932	return buf;
 933}
 934
 935static noinline_for_stack
 936char *mac_address_string(char *buf, char *end, u8 *addr,
 937			 struct printf_spec spec, const char *fmt)
 938{
 939	char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
 940	char *p = mac_addr;
 941	int i;
 942	char separator;
 943	bool reversed = false;
 944
 
 
 
 945	switch (fmt[1]) {
 946	case 'F':
 947		separator = '-';
 948		break;
 949
 950	case 'R':
 951		reversed = true;
 952		/* fall through */
 953
 954	default:
 955		separator = ':';
 956		break;
 957	}
 958
 959	for (i = 0; i < 6; i++) {
 960		if (reversed)
 961			p = hex_byte_pack(p, addr[5 - i]);
 962		else
 963			p = hex_byte_pack(p, addr[i]);
 964
 965		if (fmt[0] == 'M' && i != 5)
 966			*p++ = separator;
 967	}
 968	*p = '\0';
 969
 970	return string(buf, end, mac_addr, spec);
 971}
 972
 973static noinline_for_stack
 974char *ip4_string(char *p, const u8 *addr, const char *fmt)
 975{
 976	int i;
 977	bool leading_zeros = (fmt[0] == 'i');
 978	int index;
 979	int step;
 980
 981	switch (fmt[2]) {
 982	case 'h':
 983#ifdef __BIG_ENDIAN
 984		index = 0;
 985		step = 1;
 986#else
 987		index = 3;
 988		step = -1;
 989#endif
 990		break;
 991	case 'l':
 992		index = 3;
 993		step = -1;
 994		break;
 995	case 'n':
 996	case 'b':
 997	default:
 998		index = 0;
 999		step = 1;
1000		break;
1001	}
1002	for (i = 0; i < 4; i++) {
1003		char temp[4] __aligned(2);	/* hold each IP quad in reverse order */
1004		int digits = put_dec_trunc8(temp, addr[index]) - temp;
1005		if (leading_zeros) {
1006			if (digits < 3)
1007				*p++ = '0';
1008			if (digits < 2)
1009				*p++ = '0';
1010		}
1011		/* reverse the digits in the quad */
1012		while (digits--)
1013			*p++ = temp[digits];
1014		if (i < 3)
1015			*p++ = '.';
1016		index += step;
1017	}
1018	*p = '\0';
1019
1020	return p;
1021}
1022
1023static noinline_for_stack
1024char *ip6_compressed_string(char *p, const char *addr)
1025{
1026	int i, j, range;
1027	unsigned char zerolength[8];
1028	int longest = 1;
1029	int colonpos = -1;
1030	u16 word;
1031	u8 hi, lo;
1032	bool needcolon = false;
1033	bool useIPv4;
1034	struct in6_addr in6;
1035
1036	memcpy(&in6, addr, sizeof(struct in6_addr));
1037
1038	useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1039
1040	memset(zerolength, 0, sizeof(zerolength));
1041
1042	if (useIPv4)
1043		range = 6;
1044	else
1045		range = 8;
1046
1047	/* find position of longest 0 run */
1048	for (i = 0; i < range; i++) {
1049		for (j = i; j < range; j++) {
1050			if (in6.s6_addr16[j] != 0)
1051				break;
1052			zerolength[i]++;
1053		}
1054	}
1055	for (i = 0; i < range; i++) {
1056		if (zerolength[i] > longest) {
1057			longest = zerolength[i];
1058			colonpos = i;
1059		}
1060	}
1061	if (longest == 1)		/* don't compress a single 0 */
1062		colonpos = -1;
1063
1064	/* emit address */
1065	for (i = 0; i < range; i++) {
1066		if (i == colonpos) {
1067			if (needcolon || i == 0)
1068				*p++ = ':';
1069			*p++ = ':';
1070			needcolon = false;
1071			i += longest - 1;
1072			continue;
1073		}
1074		if (needcolon) {
1075			*p++ = ':';
1076			needcolon = false;
1077		}
1078		/* hex u16 without leading 0s */
1079		word = ntohs(in6.s6_addr16[i]);
1080		hi = word >> 8;
1081		lo = word & 0xff;
1082		if (hi) {
1083			if (hi > 0x0f)
1084				p = hex_byte_pack(p, hi);
1085			else
1086				*p++ = hex_asc_lo(hi);
1087			p = hex_byte_pack(p, lo);
1088		}
1089		else if (lo > 0x0f)
1090			p = hex_byte_pack(p, lo);
1091		else
1092			*p++ = hex_asc_lo(lo);
1093		needcolon = true;
1094	}
1095
1096	if (useIPv4) {
1097		if (needcolon)
1098			*p++ = ':';
1099		p = ip4_string(p, &in6.s6_addr[12], "I4");
1100	}
1101	*p = '\0';
1102
1103	return p;
1104}
1105
1106static noinline_for_stack
1107char *ip6_string(char *p, const char *addr, const char *fmt)
1108{
1109	int i;
1110
1111	for (i = 0; i < 8; i++) {
1112		p = hex_byte_pack(p, *addr++);
1113		p = hex_byte_pack(p, *addr++);
1114		if (fmt[0] == 'I' && i != 7)
1115			*p++ = ':';
1116	}
1117	*p = '\0';
1118
1119	return p;
1120}
1121
1122static noinline_for_stack
1123char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1124		      struct printf_spec spec, const char *fmt)
1125{
1126	char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1127
1128	if (fmt[0] == 'I' && fmt[2] == 'c')
1129		ip6_compressed_string(ip6_addr, addr);
1130	else
1131		ip6_string(ip6_addr, addr, fmt);
1132
1133	return string(buf, end, ip6_addr, spec);
1134}
1135
1136static noinline_for_stack
1137char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1138		      struct printf_spec spec, const char *fmt)
1139{
1140	char ip4_addr[sizeof("255.255.255.255")];
1141
1142	ip4_string(ip4_addr, addr, fmt);
1143
1144	return string(buf, end, ip4_addr, spec);
1145}
1146
1147static noinline_for_stack
1148char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1149			 struct printf_spec spec, const char *fmt)
1150{
1151	bool have_p = false, have_s = false, have_f = false, have_c = false;
1152	char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1153		      sizeof(":12345") + sizeof("/123456789") +
1154		      sizeof("%1234567890")];
1155	char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1156	const u8 *addr = (const u8 *) &sa->sin6_addr;
1157	char fmt6[2] = { fmt[0], '6' };
1158	u8 off = 0;
1159
1160	fmt++;
1161	while (isalpha(*++fmt)) {
1162		switch (*fmt) {
1163		case 'p':
1164			have_p = true;
1165			break;
1166		case 'f':
1167			have_f = true;
1168			break;
1169		case 's':
1170			have_s = true;
1171			break;
1172		case 'c':
1173			have_c = true;
1174			break;
1175		}
1176	}
1177
1178	if (have_p || have_s || have_f) {
1179		*p = '[';
1180		off = 1;
1181	}
1182
1183	if (fmt6[0] == 'I' && have_c)
1184		p = ip6_compressed_string(ip6_addr + off, addr);
1185	else
1186		p = ip6_string(ip6_addr + off, addr, fmt6);
1187
1188	if (have_p || have_s || have_f)
1189		*p++ = ']';
1190
1191	if (have_p) {
1192		*p++ = ':';
1193		p = number(p, pend, ntohs(sa->sin6_port), spec);
1194	}
1195	if (have_f) {
1196		*p++ = '/';
1197		p = number(p, pend, ntohl(sa->sin6_flowinfo &
1198					  IPV6_FLOWINFO_MASK), spec);
1199	}
1200	if (have_s) {
1201		*p++ = '%';
1202		p = number(p, pend, sa->sin6_scope_id, spec);
1203	}
1204	*p = '\0';
1205
1206	return string(buf, end, ip6_addr, spec);
1207}
1208
1209static noinline_for_stack
1210char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1211			 struct printf_spec spec, const char *fmt)
1212{
1213	bool have_p = false;
1214	char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1215	char *pend = ip4_addr + sizeof(ip4_addr);
1216	const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1217	char fmt4[3] = { fmt[0], '4', 0 };
1218
1219	fmt++;
1220	while (isalpha(*++fmt)) {
1221		switch (*fmt) {
1222		case 'p':
1223			have_p = true;
1224			break;
1225		case 'h':
1226		case 'l':
1227		case 'n':
1228		case 'b':
1229			fmt4[2] = *fmt;
1230			break;
1231		}
1232	}
1233
1234	p = ip4_string(ip4_addr, addr, fmt4);
1235	if (have_p) {
1236		*p++ = ':';
1237		p = number(p, pend, ntohs(sa->sin_port), spec);
1238	}
1239	*p = '\0';
1240
1241	return string(buf, end, ip4_addr, spec);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1242}
1243
1244static noinline_for_stack
1245char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1246		     const char *fmt)
1247{
1248	bool found = true;
1249	int count = 1;
1250	unsigned int flags = 0;
1251	int len;
1252
1253	if (spec.field_width == 0)
1254		return buf;				/* nothing to print */
1255
1256	if (ZERO_OR_NULL_PTR(addr))
1257		return string(buf, end, NULL, spec);	/* NULL pointer */
1258
1259
1260	do {
1261		switch (fmt[count++]) {
1262		case 'a':
1263			flags |= ESCAPE_ANY;
1264			break;
1265		case 'c':
1266			flags |= ESCAPE_SPECIAL;
1267			break;
1268		case 'h':
1269			flags |= ESCAPE_HEX;
1270			break;
1271		case 'n':
1272			flags |= ESCAPE_NULL;
1273			break;
1274		case 'o':
1275			flags |= ESCAPE_OCTAL;
1276			break;
1277		case 'p':
1278			flags |= ESCAPE_NP;
1279			break;
1280		case 's':
1281			flags |= ESCAPE_SPACE;
1282			break;
1283		default:
1284			found = false;
1285			break;
1286		}
1287	} while (found);
1288
1289	if (!flags)
1290		flags = ESCAPE_ANY_NP;
1291
1292	len = spec.field_width < 0 ? 1 : spec.field_width;
1293
1294	/*
1295	 * string_escape_mem() writes as many characters as it can to
1296	 * the given buffer, and returns the total size of the output
1297	 * had the buffer been big enough.
1298	 */
1299	buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1300
1301	return buf;
1302}
1303
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1304static noinline_for_stack
1305char *uuid_string(char *buf, char *end, const u8 *addr,
1306		  struct printf_spec spec, const char *fmt)
1307{
1308	char uuid[UUID_STRING_LEN + 1];
1309	char *p = uuid;
1310	int i;
1311	const u8 *index = uuid_be_index;
1312	bool uc = false;
1313
 
 
 
1314	switch (*(++fmt)) {
1315	case 'L':
1316		uc = true;		/* fall-through */
 
1317	case 'l':
1318		index = uuid_le_index;
1319		break;
1320	case 'B':
1321		uc = true;
1322		break;
1323	}
1324
1325	for (i = 0; i < 16; i++) {
1326		if (uc)
1327			p = hex_byte_pack_upper(p, addr[index[i]]);
1328		else
1329			p = hex_byte_pack(p, addr[index[i]]);
1330		switch (i) {
1331		case 3:
1332		case 5:
1333		case 7:
1334		case 9:
1335			*p++ = '-';
1336			break;
1337		}
1338	}
1339
1340	*p = 0;
1341
1342	return string(buf, end, uuid, spec);
1343}
1344
1345static noinline_for_stack
1346char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
 
1347{
1348	unsigned long long num;
1349	int size;
1350
 
 
 
1351	switch (fmt[1]) {
1352	case 'F':
1353		num = *(const netdev_features_t *)addr;
1354		size = sizeof(netdev_features_t);
1355		break;
1356	default:
1357		num = (unsigned long)addr;
1358		size = sizeof(unsigned long);
1359		break;
1360	}
1361
1362	return special_hex_number(buf, end, num, size);
1363}
1364
1365static noinline_for_stack
1366char *address_val(char *buf, char *end, const void *addr, const char *fmt)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1367{
1368	unsigned long long num;
1369	int size;
1370
 
 
 
1371	switch (fmt[1]) {
1372	case 'd':
1373		num = *(const dma_addr_t *)addr;
1374		size = sizeof(dma_addr_t);
1375		break;
1376	case 'p':
1377	default:
1378		num = *(const phys_addr_t *)addr;
1379		size = sizeof(phys_addr_t);
1380		break;
1381	}
1382
1383	return special_hex_number(buf, end, num, size);
1384}
1385
1386static noinline_for_stack
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1387char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1388	    const char *fmt)
1389{
1390	if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
1391		return string(buf, end, NULL, spec);
 
 
 
1392
1393	switch (fmt[1]) {
1394	case 'r':
1395		return number(buf, end, clk_get_rate(clk), spec);
1396
1397	case 'n':
1398	default:
1399#ifdef CONFIG_COMMON_CLK
1400		return string(buf, end, __clk_get_name(clk), spec);
1401#else
1402		return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
1403#endif
1404	}
1405}
1406
1407static
1408char *format_flags(char *buf, char *end, unsigned long flags,
1409					const struct trace_print_flags *names)
1410{
1411	unsigned long mask;
1412	const struct printf_spec strspec = {
1413		.field_width = -1,
1414		.precision = -1,
1415	};
1416	const struct printf_spec numspec = {
1417		.flags = SPECIAL|SMALL,
1418		.field_width = -1,
1419		.precision = -1,
1420		.base = 16,
1421	};
1422
1423	for ( ; flags && names->name; names++) {
1424		mask = names->mask;
1425		if ((flags & mask) != mask)
1426			continue;
1427
1428		buf = string(buf, end, names->name, strspec);
1429
1430		flags &= ~mask;
1431		if (flags) {
1432			if (buf < end)
1433				*buf = '|';
1434			buf++;
1435		}
1436	}
1437
1438	if (flags)
1439		buf = number(buf, end, flags, numspec);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1440
1441	return buf;
1442}
1443
1444static noinline_for_stack
1445char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
 
1446{
1447	unsigned long flags;
1448	const struct trace_print_flags *names;
1449
 
 
 
1450	switch (fmt[1]) {
1451	case 'p':
1452		flags = *(unsigned long *)flags_ptr;
1453		/* Remove zone id */
1454		flags &= (1UL << NR_PAGEFLAGS) - 1;
1455		names = pageflag_names;
1456		break;
1457	case 'v':
1458		flags = *(unsigned long *)flags_ptr;
1459		names = vmaflag_names;
1460		break;
1461	case 'g':
1462		flags = *(gfp_t *)flags_ptr;
1463		names = gfpflag_names;
1464		break;
1465	default:
1466		WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1467		return buf;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1468	}
1469
1470	return format_flags(buf, end, flags, names);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1471}
1472
1473int kptr_restrict __read_mostly;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1474
1475/*
1476 * Show a '%p' thing.  A kernel extension is that the '%p' is followed
1477 * by an extra set of alphanumeric characters that are extended format
1478 * specifiers.
1479 *
 
 
 
1480 * Right now we handle:
1481 *
1482 * - 'F' For symbolic function descriptor pointers with offset
1483 * - 'f' For simple symbolic function names without offset
1484 * - 'S' For symbolic direct pointers with offset
1485 * - 's' For symbolic direct pointers without offset
1486 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
 
1487 * - 'B' For backtraced symbolic direct pointers with offset
 
1488 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1489 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1490 * - 'b[l]' For a bitmap, the number of bits is determined by the field
1491 *       width which must be explicitly specified either as part of the
1492 *       format string '%32b[l]' or through '%*b[l]', [l] selects
1493 *       range-list format instead of hex format
1494 * - 'M' For a 6-byte MAC address, it prints the address in the
1495 *       usual colon-separated hex notation
1496 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1497 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1498 *       with a dash-separated hex notation
1499 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1500 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1501 *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1502 *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
1503 *       [S][pfs]
1504 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1505 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1506 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1507 *       IPv6 omits the colons (01020304...0f)
1508 *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1509 *       [S][pfs]
1510 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1511 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1512 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1513 * - 'I[6S]c' for IPv6 addresses printed as specified by
1514 *       http://tools.ietf.org/html/rfc5952
1515 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1516 *                of the following flags (see string_escape_mem() for the
1517 *                details):
1518 *                  a - ESCAPE_ANY
1519 *                  c - ESCAPE_SPECIAL
1520 *                  h - ESCAPE_HEX
1521 *                  n - ESCAPE_NULL
1522 *                  o - ESCAPE_OCTAL
1523 *                  p - ESCAPE_NP
1524 *                  s - ESCAPE_SPACE
1525 *                By default ESCAPE_ANY_NP is used.
1526 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1527 *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1528 *       Options for %pU are:
1529 *         b big endian lower case hex (default)
1530 *         B big endian UPPER case hex
1531 *         l little endian lower case hex
1532 *         L little endian UPPER case hex
1533 *           big endian output byte order is:
1534 *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1535 *           little endian output byte order is:
1536 *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1537 * - 'V' For a struct va_format which contains a format string * and va_list *,
1538 *       call vsnprintf(->format, *->va_list).
1539 *       Implements a "recursive vsnprintf".
1540 *       Do not use this feature without some mechanism to verify the
1541 *       correctness of the format string and va_list arguments.
1542 * - 'K' For a kernel pointer that should be hidden from unprivileged users
 
 
1543 * - 'NF' For a netdev_features_t
 
1544 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1545 *            a certain separator (' ' by default):
1546 *              C colon
1547 *              D dash
1548 *              N no separator
1549 *            The maximum supported length is 64 bytes of the input. Consider
1550 *            to use print_hex_dump() for the larger input.
1551 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1552 *           (default assumed to be phys_addr_t, passed by reference)
1553 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1554 * - 'D[234]' Same as 'd' but for a struct file
1555 * - 'g' For block_device name (gendisk + partition number)
 
 
 
1556 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
1557 *       (legacy clock framework) of the clock
1558 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
1559 *        (legacy clock framework) of the clock
1560 * - 'Cr' For a clock, it prints the current rate of the clock
1561 * - 'G' For flags to be printed as a collection of symbolic strings that would
1562 *       construct the specific value. Supported flags given by option:
1563 *       p page flags (see struct page) given as pointer to unsigned long
1564 *       g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
1565 *       v vma flags (VM_*) given as pointer to unsigned long
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1566 *
1567 * ** Please update also Documentation/printk-formats.txt when making changes **
 
1568 *
1569 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1570 * function pointers are really function descriptors, which contain a
1571 * pointer to the real address.
1572 */
1573static noinline_for_stack
1574char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1575	      struct printf_spec spec)
1576{
1577	const int default_width = 2 * sizeof(void *);
1578
1579	if (!ptr && *fmt != 'K') {
1580		/*
1581		 * Print (null) with the same width as a pointer so it makes
1582		 * tabular output look nice.
1583		 */
1584		if (spec.field_width == -1)
1585			spec.field_width = default_width;
1586		return string(buf, end, "(null)", spec);
1587	}
1588
1589	switch (*fmt) {
1590	case 'F':
1591	case 'f':
1592		ptr = dereference_function_descriptor(ptr);
1593		/* Fallthrough */
1594	case 'S':
1595	case 's':
 
 
1596	case 'B':
1597		return symbol_string(buf, end, ptr, spec, fmt);
1598	case 'R':
1599	case 'r':
1600		return resource_string(buf, end, ptr, spec, fmt);
1601	case 'h':
1602		return hex_string(buf, end, ptr, spec, fmt);
1603	case 'b':
1604		switch (fmt[1]) {
1605		case 'l':
1606			return bitmap_list_string(buf, end, ptr, spec, fmt);
1607		default:
1608			return bitmap_string(buf, end, ptr, spec, fmt);
1609		}
1610	case 'M':			/* Colon separated: 00:01:02:03:04:05 */
1611	case 'm':			/* Contiguous: 000102030405 */
1612					/* [mM]F (FDDI) */
1613					/* [mM]R (Reverse order; Bluetooth) */
1614		return mac_address_string(buf, end, ptr, spec, fmt);
1615	case 'I':			/* Formatted IP supported
1616					 * 4:	1.2.3.4
1617					 * 6:	0001:0203:...:0708
1618					 * 6c:	1::708 or 1::1.2.3.4
1619					 */
1620	case 'i':			/* Contiguous:
1621					 * 4:	001.002.003.004
1622					 * 6:   000102...0f
1623					 */
1624		switch (fmt[1]) {
1625		case '6':
1626			return ip6_addr_string(buf, end, ptr, spec, fmt);
1627		case '4':
1628			return ip4_addr_string(buf, end, ptr, spec, fmt);
1629		case 'S': {
1630			const union {
1631				struct sockaddr		raw;
1632				struct sockaddr_in	v4;
1633				struct sockaddr_in6	v6;
1634			} *sa = ptr;
1635
1636			switch (sa->raw.sa_family) {
1637			case AF_INET:
1638				return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1639			case AF_INET6:
1640				return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1641			default:
1642				return string(buf, end, "(invalid address)", spec);
1643			}}
1644		}
1645		break;
1646	case 'E':
1647		return escaped_string(buf, end, ptr, spec, fmt);
1648	case 'U':
1649		return uuid_string(buf, end, ptr, spec, fmt);
1650	case 'V':
1651		{
1652			va_list va;
1653
1654			va_copy(va, *((struct va_format *)ptr)->va);
1655			buf += vsnprintf(buf, end > buf ? end - buf : 0,
1656					 ((struct va_format *)ptr)->fmt, va);
1657			va_end(va);
1658			return buf;
1659		}
1660	case 'K':
1661		switch (kptr_restrict) {
1662		case 0:
1663			/* Always print %pK values */
1664			break;
1665		case 1: {
1666			const struct cred *cred;
1667
1668			/*
1669			 * kptr_restrict==1 cannot be used in IRQ context
1670			 * because its test for CAP_SYSLOG would be meaningless.
1671			 */
1672			if (in_irq() || in_serving_softirq() || in_nmi()) {
1673				if (spec.field_width == -1)
1674					spec.field_width = default_width;
1675				return string(buf, end, "pK-error", spec);
1676			}
1677
1678			/*
1679			 * Only print the real pointer value if the current
1680			 * process has CAP_SYSLOG and is running with the
1681			 * same credentials it started with. This is because
1682			 * access to files is checked at open() time, but %pK
1683			 * checks permission at read() time. We don't want to
1684			 * leak pointer values if a binary opens a file using
1685			 * %pK and then elevates privileges before reading it.
1686			 */
1687			cred = current_cred();
1688			if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1689			    !uid_eq(cred->euid, cred->uid) ||
1690			    !gid_eq(cred->egid, cred->gid))
1691				ptr = NULL;
1692			break;
1693		}
1694		case 2:
1695		default:
1696			/* Always print 0's for %pK */
1697			ptr = NULL;
1698			break;
1699		}
1700		break;
1701
1702	case 'N':
1703		return netdev_bits(buf, end, ptr, fmt);
 
 
1704	case 'a':
1705		return address_val(buf, end, ptr, fmt);
1706	case 'd':
1707		return dentry_name(buf, end, ptr, spec, fmt);
 
 
1708	case 'C':
1709		return clock(buf, end, ptr, spec, fmt);
1710	case 'D':
1711		return dentry_name(buf, end,
1712				   ((const struct file *)ptr)->f_path.dentry,
1713				   spec, fmt);
1714#ifdef CONFIG_BLOCK
1715	case 'g':
1716		return bdev_name(buf, end, ptr, spec, fmt);
1717#endif
1718
1719	case 'G':
1720		return flags_string(buf, end, ptr, fmt);
1721	}
1722	spec.flags |= SMALL;
1723	if (spec.field_width == -1) {
1724		spec.field_width = default_width;
1725		spec.flags |= ZEROPAD;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1726	}
1727	spec.base = 16;
1728
1729	return number(buf, end, (unsigned long) ptr, spec);
 
 
 
 
 
 
 
1730}
1731
1732/*
1733 * Helper function to decode printf style format.
1734 * Each call decode a token from the format and return the
1735 * number of characters read (or likely the delta where it wants
1736 * to go on the next call).
1737 * The decoded token is returned through the parameters
1738 *
1739 * 'h', 'l', or 'L' for integer fields
1740 * 'z' support added 23/7/1999 S.H.
1741 * 'z' changed to 'Z' --davidm 1/25/99
 
1742 * 't' added for ptrdiff_t
1743 *
1744 * @fmt: the format string
1745 * @type of the token returned
1746 * @flags: various flags such as +, -, # tokens..
1747 * @field_width: overwritten width
1748 * @base: base of the number (octal, hex, ...)
1749 * @precision: precision of a number
1750 * @qualifier: qualifier of a number (long, size_t, ...)
1751 */
1752static noinline_for_stack
1753int format_decode(const char *fmt, struct printf_spec *spec)
1754{
1755	const char *start = fmt;
1756	char qualifier;
1757
1758	/* we finished early by reading the field width */
1759	if (spec->type == FORMAT_TYPE_WIDTH) {
1760		if (spec->field_width < 0) {
1761			spec->field_width = -spec->field_width;
1762			spec->flags |= LEFT;
1763		}
1764		spec->type = FORMAT_TYPE_NONE;
1765		goto precision;
1766	}
1767
1768	/* we finished early by reading the precision */
1769	if (spec->type == FORMAT_TYPE_PRECISION) {
1770		if (spec->precision < 0)
1771			spec->precision = 0;
1772
1773		spec->type = FORMAT_TYPE_NONE;
1774		goto qualifier;
1775	}
1776
1777	/* By default */
1778	spec->type = FORMAT_TYPE_NONE;
1779
1780	for (; *fmt ; ++fmt) {
1781		if (*fmt == '%')
1782			break;
1783	}
1784
1785	/* Return the current non-format string */
1786	if (fmt != start || !*fmt)
1787		return fmt - start;
1788
1789	/* Process flags */
1790	spec->flags = 0;
1791
1792	while (1) { /* this also skips first '%' */
1793		bool found = true;
1794
1795		++fmt;
1796
1797		switch (*fmt) {
1798		case '-': spec->flags |= LEFT;    break;
1799		case '+': spec->flags |= PLUS;    break;
1800		case ' ': spec->flags |= SPACE;   break;
1801		case '#': spec->flags |= SPECIAL; break;
1802		case '0': spec->flags |= ZEROPAD; break;
1803		default:  found = false;
1804		}
1805
1806		if (!found)
1807			break;
1808	}
1809
1810	/* get field width */
1811	spec->field_width = -1;
1812
1813	if (isdigit(*fmt))
1814		spec->field_width = skip_atoi(&fmt);
1815	else if (*fmt == '*') {
1816		/* it's the next argument */
1817		spec->type = FORMAT_TYPE_WIDTH;
1818		return ++fmt - start;
1819	}
1820
1821precision:
1822	/* get the precision */
1823	spec->precision = -1;
1824	if (*fmt == '.') {
1825		++fmt;
1826		if (isdigit(*fmt)) {
1827			spec->precision = skip_atoi(&fmt);
1828			if (spec->precision < 0)
1829				spec->precision = 0;
1830		} else if (*fmt == '*') {
1831			/* it's the next argument */
1832			spec->type = FORMAT_TYPE_PRECISION;
1833			return ++fmt - start;
1834		}
1835	}
1836
1837qualifier:
1838	/* get the conversion qualifier */
1839	qualifier = 0;
1840	if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1841	    _tolower(*fmt) == 'z' || *fmt == 't') {
1842		qualifier = *fmt++;
1843		if (unlikely(qualifier == *fmt)) {
1844			if (qualifier == 'l') {
1845				qualifier = 'L';
1846				++fmt;
1847			} else if (qualifier == 'h') {
1848				qualifier = 'H';
1849				++fmt;
1850			}
1851		}
1852	}
1853
1854	/* default base */
1855	spec->base = 10;
1856	switch (*fmt) {
1857	case 'c':
1858		spec->type = FORMAT_TYPE_CHAR;
1859		return ++fmt - start;
1860
1861	case 's':
1862		spec->type = FORMAT_TYPE_STR;
1863		return ++fmt - start;
1864
1865	case 'p':
1866		spec->type = FORMAT_TYPE_PTR;
1867		return ++fmt - start;
1868
1869	case '%':
1870		spec->type = FORMAT_TYPE_PERCENT_CHAR;
1871		return ++fmt - start;
1872
1873	/* integer number formats - set up the flags and "break" */
1874	case 'o':
1875		spec->base = 8;
1876		break;
1877
1878	case 'x':
1879		spec->flags |= SMALL;
 
1880
1881	case 'X':
1882		spec->base = 16;
1883		break;
1884
1885	case 'd':
1886	case 'i':
1887		spec->flags |= SIGN;
 
1888	case 'u':
1889		break;
1890
1891	case 'n':
1892		/*
1893		 * Since %n poses a greater security risk than
1894		 * utility, treat it as any other invalid or
1895		 * unsupported format specifier.
1896		 */
1897		/* Fall-through */
1898
1899	default:
1900		WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
1901		spec->type = FORMAT_TYPE_INVALID;
1902		return fmt - start;
1903	}
1904
1905	if (qualifier == 'L')
1906		spec->type = FORMAT_TYPE_LONG_LONG;
1907	else if (qualifier == 'l') {
1908		BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
1909		spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
1910	} else if (_tolower(qualifier) == 'z') {
1911		spec->type = FORMAT_TYPE_SIZE_T;
1912	} else if (qualifier == 't') {
1913		spec->type = FORMAT_TYPE_PTRDIFF;
1914	} else if (qualifier == 'H') {
1915		BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
1916		spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
1917	} else if (qualifier == 'h') {
1918		BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
1919		spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
1920	} else {
1921		BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
1922		spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
1923	}
1924
1925	return ++fmt - start;
1926}
1927
1928static void
1929set_field_width(struct printf_spec *spec, int width)
1930{
1931	spec->field_width = width;
1932	if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
1933		spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
1934	}
1935}
1936
1937static void
1938set_precision(struct printf_spec *spec, int prec)
1939{
1940	spec->precision = prec;
1941	if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
1942		spec->precision = clamp(prec, 0, PRECISION_MAX);
1943	}
1944}
1945
1946/**
1947 * vsnprintf - Format a string and place it in a buffer
1948 * @buf: The buffer to place the result into
1949 * @size: The size of the buffer, including the trailing null space
1950 * @fmt: The format string to use
1951 * @args: Arguments for the format string
1952 *
1953 * This function generally follows C99 vsnprintf, but has some
1954 * extensions and a few limitations:
1955 *
1956 * %n is unsupported
1957 * %p* is handled by pointer()
1958 *
1959 * See pointer() or Documentation/printk-formats.txt for more
1960 * extensive description.
1961 *
1962 * ** Please update the documentation in both places when making changes **
1963 *
1964 * The return value is the number of characters which would
1965 * be generated for the given input, excluding the trailing
1966 * '\0', as per ISO C99. If you want to have the exact
1967 * number of characters written into @buf as return value
1968 * (not including the trailing '\0'), use vscnprintf(). If the
1969 * return is greater than or equal to @size, the resulting
1970 * string is truncated.
1971 *
1972 * If you're not already dealing with a va_list consider using snprintf().
1973 */
1974int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1975{
1976	unsigned long long num;
1977	char *str, *end;
1978	struct printf_spec spec = {0};
1979
1980	/* Reject out-of-range values early.  Large positive sizes are
1981	   used for unknown buffer sizes. */
1982	if (WARN_ON_ONCE(size > INT_MAX))
1983		return 0;
1984
1985	str = buf;
1986	end = buf + size;
1987
1988	/* Make sure end is always >= buf */
1989	if (end < buf) {
1990		end = ((void *)-1);
1991		size = end - buf;
1992	}
1993
1994	while (*fmt) {
1995		const char *old_fmt = fmt;
1996		int read = format_decode(fmt, &spec);
1997
1998		fmt += read;
1999
2000		switch (spec.type) {
2001		case FORMAT_TYPE_NONE: {
2002			int copy = read;
2003			if (str < end) {
2004				if (copy > end - str)
2005					copy = end - str;
2006				memcpy(str, old_fmt, copy);
2007			}
2008			str += read;
2009			break;
2010		}
2011
2012		case FORMAT_TYPE_WIDTH:
2013			set_field_width(&spec, va_arg(args, int));
2014			break;
2015
2016		case FORMAT_TYPE_PRECISION:
2017			set_precision(&spec, va_arg(args, int));
2018			break;
2019
2020		case FORMAT_TYPE_CHAR: {
2021			char c;
2022
2023			if (!(spec.flags & LEFT)) {
2024				while (--spec.field_width > 0) {
2025					if (str < end)
2026						*str = ' ';
2027					++str;
2028
2029				}
2030			}
2031			c = (unsigned char) va_arg(args, int);
2032			if (str < end)
2033				*str = c;
2034			++str;
2035			while (--spec.field_width > 0) {
2036				if (str < end)
2037					*str = ' ';
2038				++str;
2039			}
2040			break;
2041		}
2042
2043		case FORMAT_TYPE_STR:
2044			str = string(str, end, va_arg(args, char *), spec);
2045			break;
2046
2047		case FORMAT_TYPE_PTR:
2048			str = pointer(fmt, str, end, va_arg(args, void *),
2049				      spec);
2050			while (isalnum(*fmt))
2051				fmt++;
2052			break;
2053
2054		case FORMAT_TYPE_PERCENT_CHAR:
2055			if (str < end)
2056				*str = '%';
2057			++str;
2058			break;
2059
2060		case FORMAT_TYPE_INVALID:
2061			/*
2062			 * Presumably the arguments passed gcc's type
2063			 * checking, but there is no safe or sane way
2064			 * for us to continue parsing the format and
2065			 * fetching from the va_list; the remaining
2066			 * specifiers and arguments would be out of
2067			 * sync.
2068			 */
2069			goto out;
2070
2071		default:
2072			switch (spec.type) {
2073			case FORMAT_TYPE_LONG_LONG:
2074				num = va_arg(args, long long);
2075				break;
2076			case FORMAT_TYPE_ULONG:
2077				num = va_arg(args, unsigned long);
2078				break;
2079			case FORMAT_TYPE_LONG:
2080				num = va_arg(args, long);
2081				break;
2082			case FORMAT_TYPE_SIZE_T:
2083				if (spec.flags & SIGN)
2084					num = va_arg(args, ssize_t);
2085				else
2086					num = va_arg(args, size_t);
2087				break;
2088			case FORMAT_TYPE_PTRDIFF:
2089				num = va_arg(args, ptrdiff_t);
2090				break;
2091			case FORMAT_TYPE_UBYTE:
2092				num = (unsigned char) va_arg(args, int);
2093				break;
2094			case FORMAT_TYPE_BYTE:
2095				num = (signed char) va_arg(args, int);
2096				break;
2097			case FORMAT_TYPE_USHORT:
2098				num = (unsigned short) va_arg(args, int);
2099				break;
2100			case FORMAT_TYPE_SHORT:
2101				num = (short) va_arg(args, int);
2102				break;
2103			case FORMAT_TYPE_INT:
2104				num = (int) va_arg(args, int);
2105				break;
2106			default:
2107				num = va_arg(args, unsigned int);
2108			}
2109
2110			str = number(str, end, num, spec);
2111		}
2112	}
2113
2114out:
2115	if (size > 0) {
2116		if (str < end)
2117			*str = '\0';
2118		else
2119			end[-1] = '\0';
2120	}
2121
2122	/* the trailing null byte doesn't count towards the total */
2123	return str-buf;
2124
2125}
2126EXPORT_SYMBOL(vsnprintf);
2127
2128/**
2129 * vscnprintf - Format a string and place it in a buffer
2130 * @buf: The buffer to place the result into
2131 * @size: The size of the buffer, including the trailing null space
2132 * @fmt: The format string to use
2133 * @args: Arguments for the format string
2134 *
2135 * The return value is the number of characters which have been written into
2136 * the @buf not including the trailing '\0'. If @size is == 0 the function
2137 * returns 0.
2138 *
2139 * If you're not already dealing with a va_list consider using scnprintf().
2140 *
2141 * See the vsnprintf() documentation for format string extensions over C99.
2142 */
2143int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2144{
2145	int i;
2146
2147	i = vsnprintf(buf, size, fmt, args);
2148
2149	if (likely(i < size))
2150		return i;
2151	if (size != 0)
2152		return size - 1;
2153	return 0;
2154}
2155EXPORT_SYMBOL(vscnprintf);
2156
2157/**
2158 * snprintf - Format a string and place it in a buffer
2159 * @buf: The buffer to place the result into
2160 * @size: The size of the buffer, including the trailing null space
2161 * @fmt: The format string to use
2162 * @...: Arguments for the format string
2163 *
2164 * The return value is the number of characters which would be
2165 * generated for the given input, excluding the trailing null,
2166 * as per ISO C99.  If the return is greater than or equal to
2167 * @size, the resulting string is truncated.
2168 *
2169 * See the vsnprintf() documentation for format string extensions over C99.
2170 */
2171int snprintf(char *buf, size_t size, const char *fmt, ...)
2172{
2173	va_list args;
2174	int i;
2175
2176	va_start(args, fmt);
2177	i = vsnprintf(buf, size, fmt, args);
2178	va_end(args);
2179
2180	return i;
2181}
2182EXPORT_SYMBOL(snprintf);
2183
2184/**
2185 * scnprintf - Format a string and place it in a buffer
2186 * @buf: The buffer to place the result into
2187 * @size: The size of the buffer, including the trailing null space
2188 * @fmt: The format string to use
2189 * @...: Arguments for the format string
2190 *
2191 * The return value is the number of characters written into @buf not including
2192 * the trailing '\0'. If @size is == 0 the function returns 0.
2193 */
2194
2195int scnprintf(char *buf, size_t size, const char *fmt, ...)
2196{
2197	va_list args;
2198	int i;
2199
2200	va_start(args, fmt);
2201	i = vscnprintf(buf, size, fmt, args);
2202	va_end(args);
2203
2204	return i;
2205}
2206EXPORT_SYMBOL(scnprintf);
2207
2208/**
2209 * vsprintf - Format a string and place it in a buffer
2210 * @buf: The buffer to place the result into
2211 * @fmt: The format string to use
2212 * @args: Arguments for the format string
2213 *
2214 * The function returns the number of characters written
2215 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2216 * buffer overflows.
2217 *
2218 * If you're not already dealing with a va_list consider using sprintf().
2219 *
2220 * See the vsnprintf() documentation for format string extensions over C99.
2221 */
2222int vsprintf(char *buf, const char *fmt, va_list args)
2223{
2224	return vsnprintf(buf, INT_MAX, fmt, args);
2225}
2226EXPORT_SYMBOL(vsprintf);
2227
2228/**
2229 * sprintf - Format a string and place it in a buffer
2230 * @buf: The buffer to place the result into
2231 * @fmt: The format string to use
2232 * @...: Arguments for the format string
2233 *
2234 * The function returns the number of characters written
2235 * into @buf. Use snprintf() or scnprintf() in order to avoid
2236 * buffer overflows.
2237 *
2238 * See the vsnprintf() documentation for format string extensions over C99.
2239 */
2240int sprintf(char *buf, const char *fmt, ...)
2241{
2242	va_list args;
2243	int i;
2244
2245	va_start(args, fmt);
2246	i = vsnprintf(buf, INT_MAX, fmt, args);
2247	va_end(args);
2248
2249	return i;
2250}
2251EXPORT_SYMBOL(sprintf);
2252
2253#ifdef CONFIG_BINARY_PRINTF
2254/*
2255 * bprintf service:
2256 * vbin_printf() - VA arguments to binary data
2257 * bstr_printf() - Binary data to text string
2258 */
2259
2260/**
2261 * vbin_printf - Parse a format string and place args' binary value in a buffer
2262 * @bin_buf: The buffer to place args' binary value
2263 * @size: The size of the buffer(by words(32bits), not characters)
2264 * @fmt: The format string to use
2265 * @args: Arguments for the format string
2266 *
2267 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2268 * is skipped.
2269 *
2270 * The return value is the number of words(32bits) which would be generated for
2271 * the given input.
2272 *
2273 * NOTE:
2274 * If the return value is greater than @size, the resulting bin_buf is NOT
2275 * valid for bstr_printf().
2276 */
2277int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2278{
2279	struct printf_spec spec = {0};
2280	char *str, *end;
 
2281
2282	str = (char *)bin_buf;
2283	end = (char *)(bin_buf + size);
2284
2285#define save_arg(type)							\
2286do {									\
 
2287	if (sizeof(type) == 8) {					\
2288		unsigned long long value;				\
2289		str = PTR_ALIGN(str, sizeof(u32));			\
2290		value = va_arg(args, unsigned long long);		\
2291		if (str + sizeof(type) <= end) {			\
2292			*(u32 *)str = *(u32 *)&value;			\
2293			*(u32 *)(str + 4) = *((u32 *)&value + 1);	\
2294		}							\
 
2295	} else {							\
2296		unsigned long value;					\
2297		str = PTR_ALIGN(str, sizeof(type));			\
2298		value = va_arg(args, int);				\
2299		if (str + sizeof(type) <= end)				\
2300			*(typeof(type) *)str = (type)value;		\
 
2301	}								\
2302	str += sizeof(type);						\
2303} while (0)
 
2304
2305	while (*fmt) {
2306		int read = format_decode(fmt, &spec);
2307
2308		fmt += read;
2309
2310		switch (spec.type) {
2311		case FORMAT_TYPE_NONE:
2312		case FORMAT_TYPE_PERCENT_CHAR:
2313			break;
2314		case FORMAT_TYPE_INVALID:
2315			goto out;
2316
2317		case FORMAT_TYPE_WIDTH:
2318		case FORMAT_TYPE_PRECISION:
2319			save_arg(int);
 
 
 
2320			break;
2321
2322		case FORMAT_TYPE_CHAR:
2323			save_arg(char);
2324			break;
2325
2326		case FORMAT_TYPE_STR: {
2327			const char *save_str = va_arg(args, char *);
 
2328			size_t len;
2329
2330			if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2331					|| (unsigned long)save_str < PAGE_SIZE)
2332				save_str = "(null)";
 
2333			len = strlen(save_str) + 1;
2334			if (str + len < end)
2335				memcpy(str, save_str, len);
2336			str += len;
2337			break;
2338		}
2339
2340		case FORMAT_TYPE_PTR:
2341			save_arg(void *);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2342			/* skip all alphanumeric pointer suffixes */
2343			while (isalnum(*fmt))
2344				fmt++;
2345			break;
2346
2347		default:
2348			switch (spec.type) {
2349
2350			case FORMAT_TYPE_LONG_LONG:
2351				save_arg(long long);
2352				break;
2353			case FORMAT_TYPE_ULONG:
2354			case FORMAT_TYPE_LONG:
2355				save_arg(unsigned long);
2356				break;
2357			case FORMAT_TYPE_SIZE_T:
2358				save_arg(size_t);
2359				break;
2360			case FORMAT_TYPE_PTRDIFF:
2361				save_arg(ptrdiff_t);
2362				break;
2363			case FORMAT_TYPE_UBYTE:
2364			case FORMAT_TYPE_BYTE:
2365				save_arg(char);
2366				break;
2367			case FORMAT_TYPE_USHORT:
2368			case FORMAT_TYPE_SHORT:
2369				save_arg(short);
2370				break;
2371			default:
2372				save_arg(int);
2373			}
2374		}
2375	}
2376
2377out:
2378	return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2379#undef save_arg
2380}
2381EXPORT_SYMBOL_GPL(vbin_printf);
2382
2383/**
2384 * bstr_printf - Format a string from binary arguments and place it in a buffer
2385 * @buf: The buffer to place the result into
2386 * @size: The size of the buffer, including the trailing null space
2387 * @fmt: The format string to use
2388 * @bin_buf: Binary arguments for the format string
2389 *
2390 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2391 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2392 * a binary buffer that generated by vbin_printf.
2393 *
2394 * The format follows C99 vsnprintf, but has some extensions:
2395 *  see vsnprintf comment for details.
2396 *
2397 * The return value is the number of characters which would
2398 * be generated for the given input, excluding the trailing
2399 * '\0', as per ISO C99. If you want to have the exact
2400 * number of characters written into @buf as return value
2401 * (not including the trailing '\0'), use vscnprintf(). If the
2402 * return is greater than or equal to @size, the resulting
2403 * string is truncated.
2404 */
2405int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2406{
2407	struct printf_spec spec = {0};
2408	char *str, *end;
2409	const char *args = (const char *)bin_buf;
2410
2411	if (WARN_ON_ONCE(size > INT_MAX))
2412		return 0;
2413
2414	str = buf;
2415	end = buf + size;
2416
2417#define get_arg(type)							\
2418({									\
2419	typeof(type) value;						\
2420	if (sizeof(type) == 8) {					\
2421		args = PTR_ALIGN(args, sizeof(u32));			\
2422		*(u32 *)&value = *(u32 *)args;				\
2423		*((u32 *)&value + 1) = *(u32 *)(args + 4);		\
2424	} else {							\
2425		args = PTR_ALIGN(args, sizeof(type));			\
2426		value = *(typeof(type) *)args;				\
2427	}								\
2428	args += sizeof(type);						\
2429	value;								\
2430})
2431
2432	/* Make sure end is always >= buf */
2433	if (end < buf) {
2434		end = ((void *)-1);
2435		size = end - buf;
2436	}
2437
2438	while (*fmt) {
2439		const char *old_fmt = fmt;
2440		int read = format_decode(fmt, &spec);
2441
2442		fmt += read;
2443
2444		switch (spec.type) {
2445		case FORMAT_TYPE_NONE: {
2446			int copy = read;
2447			if (str < end) {
2448				if (copy > end - str)
2449					copy = end - str;
2450				memcpy(str, old_fmt, copy);
2451			}
2452			str += read;
2453			break;
2454		}
2455
2456		case FORMAT_TYPE_WIDTH:
2457			set_field_width(&spec, get_arg(int));
2458			break;
2459
2460		case FORMAT_TYPE_PRECISION:
2461			set_precision(&spec, get_arg(int));
2462			break;
2463
2464		case FORMAT_TYPE_CHAR: {
2465			char c;
2466
2467			if (!(spec.flags & LEFT)) {
2468				while (--spec.field_width > 0) {
2469					if (str < end)
2470						*str = ' ';
2471					++str;
2472				}
2473			}
2474			c = (unsigned char) get_arg(char);
2475			if (str < end)
2476				*str = c;
2477			++str;
2478			while (--spec.field_width > 0) {
2479				if (str < end)
2480					*str = ' ';
2481				++str;
2482			}
2483			break;
2484		}
2485
2486		case FORMAT_TYPE_STR: {
2487			const char *str_arg = args;
2488			args += strlen(str_arg) + 1;
2489			str = string(str, end, (char *)str_arg, spec);
2490			break;
2491		}
2492
2493		case FORMAT_TYPE_PTR:
2494			str = pointer(fmt, str, end, get_arg(void *), spec);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2495			while (isalnum(*fmt))
2496				fmt++;
2497			break;
 
2498
2499		case FORMAT_TYPE_PERCENT_CHAR:
2500			if (str < end)
2501				*str = '%';
2502			++str;
2503			break;
2504
2505		case FORMAT_TYPE_INVALID:
2506			goto out;
2507
2508		default: {
2509			unsigned long long num;
2510
2511			switch (spec.type) {
2512
2513			case FORMAT_TYPE_LONG_LONG:
2514				num = get_arg(long long);
2515				break;
2516			case FORMAT_TYPE_ULONG:
2517			case FORMAT_TYPE_LONG:
2518				num = get_arg(unsigned long);
2519				break;
2520			case FORMAT_TYPE_SIZE_T:
2521				num = get_arg(size_t);
2522				break;
2523			case FORMAT_TYPE_PTRDIFF:
2524				num = get_arg(ptrdiff_t);
2525				break;
2526			case FORMAT_TYPE_UBYTE:
2527				num = get_arg(unsigned char);
2528				break;
2529			case FORMAT_TYPE_BYTE:
2530				num = get_arg(signed char);
2531				break;
2532			case FORMAT_TYPE_USHORT:
2533				num = get_arg(unsigned short);
2534				break;
2535			case FORMAT_TYPE_SHORT:
2536				num = get_arg(short);
2537				break;
2538			case FORMAT_TYPE_UINT:
2539				num = get_arg(unsigned int);
2540				break;
2541			default:
2542				num = get_arg(int);
2543			}
2544
2545			str = number(str, end, num, spec);
2546		} /* default: */
2547		} /* switch(spec.type) */
2548	} /* while(*fmt) */
2549
2550out:
2551	if (size > 0) {
2552		if (str < end)
2553			*str = '\0';
2554		else
2555			end[-1] = '\0';
2556	}
2557
2558#undef get_arg
2559
2560	/* the trailing null byte doesn't count towards the total */
2561	return str - buf;
2562}
2563EXPORT_SYMBOL_GPL(bstr_printf);
2564
2565/**
2566 * bprintf - Parse a format string and place args' binary value in a buffer
2567 * @bin_buf: The buffer to place args' binary value
2568 * @size: The size of the buffer(by words(32bits), not characters)
2569 * @fmt: The format string to use
2570 * @...: Arguments for the format string
2571 *
2572 * The function returns the number of words(u32) written
2573 * into @bin_buf.
2574 */
2575int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2576{
2577	va_list args;
2578	int ret;
2579
2580	va_start(args, fmt);
2581	ret = vbin_printf(bin_buf, size, fmt, args);
2582	va_end(args);
2583
2584	return ret;
2585}
2586EXPORT_SYMBOL_GPL(bprintf);
2587
2588#endif /* CONFIG_BINARY_PRINTF */
2589
2590/**
2591 * vsscanf - Unformat a buffer into a list of arguments
2592 * @buf:	input buffer
2593 * @fmt:	format of buffer
2594 * @args:	arguments
2595 */
2596int vsscanf(const char *buf, const char *fmt, va_list args)
2597{
2598	const char *str = buf;
2599	char *next;
2600	char digit;
2601	int num = 0;
2602	u8 qualifier;
2603	unsigned int base;
2604	union {
2605		long long s;
2606		unsigned long long u;
2607	} val;
2608	s16 field_width;
2609	bool is_sign;
2610
2611	while (*fmt) {
2612		/* skip any white space in format */
2613		/* white space in format matchs any amount of
2614		 * white space, including none, in the input.
2615		 */
2616		if (isspace(*fmt)) {
2617			fmt = skip_spaces(++fmt);
2618			str = skip_spaces(str);
2619		}
2620
2621		/* anything that is not a conversion must match exactly */
2622		if (*fmt != '%' && *fmt) {
2623			if (*fmt++ != *str++)
2624				break;
2625			continue;
2626		}
2627
2628		if (!*fmt)
2629			break;
2630		++fmt;
2631
2632		/* skip this conversion.
2633		 * advance both strings to next white space
2634		 */
2635		if (*fmt == '*') {
2636			if (!*str)
2637				break;
2638			while (!isspace(*fmt) && *fmt != '%' && *fmt) {
2639				/* '%*[' not yet supported, invalid format */
2640				if (*fmt == '[')
2641					return num;
2642				fmt++;
2643			}
2644			while (!isspace(*str) && *str)
2645				str++;
2646			continue;
2647		}
2648
2649		/* get field width */
2650		field_width = -1;
2651		if (isdigit(*fmt)) {
2652			field_width = skip_atoi(&fmt);
2653			if (field_width <= 0)
2654				break;
2655		}
2656
2657		/* get conversion qualifier */
2658		qualifier = -1;
2659		if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2660		    _tolower(*fmt) == 'z') {
2661			qualifier = *fmt++;
2662			if (unlikely(qualifier == *fmt)) {
2663				if (qualifier == 'h') {
2664					qualifier = 'H';
2665					fmt++;
2666				} else if (qualifier == 'l') {
2667					qualifier = 'L';
2668					fmt++;
2669				}
2670			}
2671		}
2672
2673		if (!*fmt)
2674			break;
2675
2676		if (*fmt == 'n') {
2677			/* return number of characters read so far */
2678			*va_arg(args, int *) = str - buf;
2679			++fmt;
2680			continue;
2681		}
2682
2683		if (!*str)
2684			break;
2685
2686		base = 10;
2687		is_sign = false;
2688
2689		switch (*fmt++) {
2690		case 'c':
2691		{
2692			char *s = (char *)va_arg(args, char*);
2693			if (field_width == -1)
2694				field_width = 1;
2695			do {
2696				*s++ = *str++;
2697			} while (--field_width > 0 && *str);
2698			num++;
2699		}
2700		continue;
2701		case 's':
2702		{
2703			char *s = (char *)va_arg(args, char *);
2704			if (field_width == -1)
2705				field_width = SHRT_MAX;
2706			/* first, skip leading white space in buffer */
2707			str = skip_spaces(str);
2708
2709			/* now copy until next white space */
2710			while (*str && !isspace(*str) && field_width--)
2711				*s++ = *str++;
2712			*s = '\0';
2713			num++;
2714		}
2715		continue;
2716		/*
2717		 * Warning: This implementation of the '[' conversion specifier
2718		 * deviates from its glibc counterpart in the following ways:
2719		 * (1) It does NOT support ranges i.e. '-' is NOT a special
2720		 *     character
2721		 * (2) It cannot match the closing bracket ']' itself
2722		 * (3) A field width is required
2723		 * (4) '%*[' (discard matching input) is currently not supported
2724		 *
2725		 * Example usage:
2726		 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
2727		 *		buf1, buf2, buf3);
2728		 * if (ret < 3)
2729		 *    // etc..
2730		 */
2731		case '[':
2732		{
2733			char *s = (char *)va_arg(args, char *);
2734			DECLARE_BITMAP(set, 256) = {0};
2735			unsigned int len = 0;
2736			bool negate = (*fmt == '^');
2737
2738			/* field width is required */
2739			if (field_width == -1)
2740				return num;
2741
2742			if (negate)
2743				++fmt;
2744
2745			for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
2746				set_bit((u8)*fmt, set);
2747
2748			/* no ']' or no character set found */
2749			if (!*fmt || !len)
2750				return num;
2751			++fmt;
2752
2753			if (negate) {
2754				bitmap_complement(set, set, 256);
2755				/* exclude null '\0' byte */
2756				clear_bit(0, set);
2757			}
2758
2759			/* match must be non-empty */
2760			if (!test_bit((u8)*str, set))
2761				return num;
2762
2763			while (test_bit((u8)*str, set) && field_width--)
2764				*s++ = *str++;
2765			*s = '\0';
2766			++num;
2767		}
2768		continue;
2769		case 'o':
2770			base = 8;
2771			break;
2772		case 'x':
2773		case 'X':
2774			base = 16;
2775			break;
2776		case 'i':
2777			base = 0;
 
2778		case 'd':
2779			is_sign = true;
 
2780		case 'u':
2781			break;
2782		case '%':
2783			/* looking for '%' in str */
2784			if (*str++ != '%')
2785				return num;
2786			continue;
2787		default:
2788			/* invalid format; stop here */
2789			return num;
2790		}
2791
2792		/* have some sort of integer conversion.
2793		 * first, skip white space in buffer.
2794		 */
2795		str = skip_spaces(str);
2796
2797		digit = *str;
2798		if (is_sign && digit == '-')
 
 
 
2799			digit = *(str + 1);
 
2800
2801		if (!digit
2802		    || (base == 16 && !isxdigit(digit))
2803		    || (base == 10 && !isdigit(digit))
2804		    || (base == 8 && (!isdigit(digit) || digit > '7'))
2805		    || (base == 0 && !isdigit(digit)))
2806			break;
2807
2808		if (is_sign)
2809			val.s = qualifier != 'L' ?
2810				simple_strtol(str, &next, base) :
2811				simple_strtoll(str, &next, base);
2812		else
2813			val.u = qualifier != 'L' ?
2814				simple_strtoul(str, &next, base) :
2815				simple_strtoull(str, &next, base);
2816
2817		if (field_width > 0 && next - str > field_width) {
2818			if (base == 0)
2819				_parse_integer_fixup_radix(str, &base);
2820			while (next - str > field_width) {
2821				if (is_sign)
2822					val.s = div_s64(val.s, base);
2823				else
2824					val.u = div_u64(val.u, base);
2825				--next;
2826			}
2827		}
2828
2829		switch (qualifier) {
2830		case 'H':	/* that's 'hh' in format */
2831			if (is_sign)
2832				*va_arg(args, signed char *) = val.s;
2833			else
2834				*va_arg(args, unsigned char *) = val.u;
2835			break;
2836		case 'h':
2837			if (is_sign)
2838				*va_arg(args, short *) = val.s;
2839			else
2840				*va_arg(args, unsigned short *) = val.u;
2841			break;
2842		case 'l':
2843			if (is_sign)
2844				*va_arg(args, long *) = val.s;
2845			else
2846				*va_arg(args, unsigned long *) = val.u;
2847			break;
2848		case 'L':
2849			if (is_sign)
2850				*va_arg(args, long long *) = val.s;
2851			else
2852				*va_arg(args, unsigned long long *) = val.u;
2853			break;
2854		case 'Z':
2855		case 'z':
2856			*va_arg(args, size_t *) = val.u;
2857			break;
2858		default:
2859			if (is_sign)
2860				*va_arg(args, int *) = val.s;
2861			else
2862				*va_arg(args, unsigned int *) = val.u;
2863			break;
2864		}
2865		num++;
2866
2867		if (!next)
2868			break;
2869		str = next;
2870	}
2871
2872	return num;
2873}
2874EXPORT_SYMBOL(vsscanf);
2875
2876/**
2877 * sscanf - Unformat a buffer into a list of arguments
2878 * @buf:	input buffer
2879 * @fmt:	formatting of buffer
2880 * @...:	resulting arguments
2881 */
2882int sscanf(const char *buf, const char *fmt, ...)
2883{
2884	va_list args;
2885	int i;
2886
2887	va_start(args, fmt);
2888	i = vsscanf(buf, fmt, args);
2889	va_end(args);
2890
2891	return i;
2892}
2893EXPORT_SYMBOL(sscanf);