lib/vsprintf.c

   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/module.h>       /* for KSYM_SYMBOL_LEN */
  25 #include <linux/types.h>
  26 #include <linux/string.h>
  27 #include <linux/ctype.h>
  28 #include <linux/kernel.h>
  29 #include <linux/kallsyms.h>
  30 #include <linux/math64.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/ioport.h>
  33 #include <linux/dcache.h>
  34 #include <linux/cred.h>
  35 #include <linux/rtc.h>
  36 #include <linux/uuid.h>
  37 #include <linux/of.h>
  38 #include <net/addrconf.h>
  39 #include <linux/siphash.h>
  40 #include <linux/compiler.h>
  41 #ifdef CONFIG_BLOCK
  42 #include <linux/blkdev.h>
  43 #endif
  44
  45 #include "../mm/internal.h"     /* For the trace_print_flags arrays */
  46
  47 #include <asm/page.h>           /* for PAGE_SIZE */
  48 #include <asm/byteorder.h>      /* cpu_to_le16 */
  49
  50 #include <linux/string_helpers.h>
  51 #include "kstrtox.h"
  52
  53 /**
  54  * simple_strtoull - convert a string to an unsigned long long
  55  * @cp: The start of the string
  56  * @endp: A pointer to the end of the parsed string will be placed here
  57  * @base: The number base to use
  58  *
  59  * This function is obsolete. Please use kstrtoull instead.
  60  */
  61 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
  62 {
  63         unsigned long long result;
  64         unsigned int rv;
  65
  66         cp = _parse_integer_fixup_radix(cp, &base);
  67         rv = _parse_integer(cp, base, &result);
  68         /* FIXME */
  69         cp += (rv & ~KSTRTOX_OVERFLOW);
  70
  71         if (endp)
  72                 *endp = (char *)cp;
  73
  74         return result;
  75 }
  76 EXPORT_SYMBOL(simple_strtoull);
  77
  78 /**
  79  * simple_strtoul - convert a string to an unsigned long
  80  * @cp: The start of the string
  81  * @endp: A pointer to the end of the parsed string will be placed here
  82  * @base: The number base to use
  83  *
  84  * This function is obsolete. Please use kstrtoul instead.
  85  */
  86 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
  87 {
  88         return simple_strtoull(cp, endp, base);
  89 }
  90 EXPORT_SYMBOL(simple_strtoul);
  91
  92 /**
  93  * simple_strtol - convert a string to a signed long
  94  * @cp: The start of the string
  95  * @endp: A pointer to the end of the parsed string will be placed here
  96  * @base: The number base to use
  97  *
  98  * This function is obsolete. Please use kstrtol instead.
  99  */
 100 long simple_strtol(const char *cp, char **endp, unsigned int base)
 101 {
 102         if (*cp == '-')
 103                 return -simple_strtoul(cp + 1, endp, base);
 104
 105         return simple_strtoul(cp, endp, base);
 106 }
 107 EXPORT_SYMBOL(simple_strtol);
 108
 109 /**
 110  * simple_strtoll - convert a string to a signed long long
 111  * @cp: The start of the string
 112  * @endp: A pointer to the end of the parsed string will be placed here
 113  * @base: The number base to use
 114  *
 115  * This function is obsolete. Please use kstrtoll instead.
 116  */
 117 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
 118 {
 119         if (*cp == '-')
 120                 return -simple_strtoull(cp + 1, endp, base);
 121
 122         return simple_strtoull(cp, endp, base);
 123 }
 124 EXPORT_SYMBOL(simple_strtoll);
 125
 126 static noinline_for_stack
 127 int skip_atoi(const char **s)
 128 {
 129         int i = 0;
 130
 131         do {
 132                 i = i*10 + *((*s)++) - '0';
 133         } while (isdigit(**s));
 134
 135         return i;
 136 }
 137
 138 /*
 139  * Decimal conversion is by far the most typical, and is used for
 140  * /proc and /sys data. This directly impacts e.g. top performance
 141  * with many processes running. We optimize it for speed by emitting
 142  * two characters at a time, using a 200 byte lookup table. This
 143  * roughly halves the number of multiplications compared to computing
 144  * the digits one at a time. Implementation strongly inspired by the
 145  * previous version, which in turn used ideas described at
 146  * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
 147  * from the author, Douglas W. Jones).
 148  *
 149  * It turns out there is precisely one 26 bit fixed-point
 150  * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
 151  * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
 152  * range happens to be somewhat larger (x <= 1073741898), but that's
 153  * irrelevant for our purpose.
 154  *
 155  * For dividing a number in the range [10^4, 10^6-1] by 100, we still
 156  * need a 32x32->64 bit multiply, so we simply use the same constant.
 157  *
 158  * For dividing a number in the range [100, 10^4-1] by 100, there are
 159  * several options. The simplest is (x * 0x147b) >> 19, which is valid
 160  * for all x <= 43698.
 161  */
 162
 163 static const u16 decpair[100] = {
 164 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
 165         _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
 166         _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
 167         _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
 168         _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
 169         _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
 170         _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
 171         _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
 172         _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
 173         _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
 174         _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
 175 #undef _
 176 };
 177
 178 /*
 179  * This will print a single '0' even if r == 0, since we would
 180  * immediately jump to out_r where two 0s would be written but only
 181  * one of them accounted for in buf. This is needed by ip4_string
 182  * below. All other callers pass a non-zero value of r.
 183 */
 184 static noinline_for_stack
 185 char *put_dec_trunc8(char *buf, unsigned r)
 186 {
 187         unsigned q;
 188
 189         /* 1 <= r < 10^8 */
 190         if (r < 100)
 191                 goto out_r;
 192
 193         /* 100 <= r < 10^8 */
 194         q = (r * (u64)0x28f5c29) >> 32;
 195         *((u16 *)buf) = decpair[r - 100*q];
 196         buf += 2;
 197
 198         /* 1 <= q < 10^6 */
 199         if (q < 100)
 200                 goto out_q;
 201
 202         /*  100 <= q < 10^6 */
 203         r = (q * (u64)0x28f5c29) >> 32;
 204         *((u16 *)buf) = decpair[q - 100*r];
 205         buf += 2;
 206
 207         /* 1 <= r < 10^4 */
 208         if (r < 100)
 209                 goto out_r;
 210
 211         /* 100 <= r < 10^4 */
 212         q = (r * 0x147b) >> 19;
 213         *((u16 *)buf) = decpair[r - 100*q];
 214         buf += 2;
 215 out_q:
 216         /* 1 <= q < 100 */
 217         r = q;
 218 out_r:
 219         /* 1 <= r < 100 */
 220         *((u16 *)buf) = decpair[r];
 221         buf += r < 10 ? 1 : 2;
 222         return buf;
 223 }
 224
 225 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
 226 static noinline_for_stack
 227 char *put_dec_full8(char *buf, unsigned r)
 228 {
 229         unsigned q;
 230
 231         /* 0 <= r < 10^8 */
 232         q = (r * (u64)0x28f5c29) >> 32;
 233         *((u16 *)buf) = decpair[r - 100*q];
 234         buf += 2;
 235
 236         /* 0 <= q < 10^6 */
 237         r = (q * (u64)0x28f5c29) >> 32;
 238         *((u16 *)buf) = decpair[q - 100*r];
 239         buf += 2;
 240
 241         /* 0 <= r < 10^4 */
 242         q = (r * 0x147b) >> 19;
 243         *((u16 *)buf) = decpair[r - 100*q];
 244         buf += 2;
 245
 246         /* 0 <= q < 100 */
 247         *((u16 *)buf) = decpair[q];
 248         buf += 2;
 249         return buf;
 250 }
 251
 252 static noinline_for_stack
 253 char *put_dec(char *buf, unsigned long long n)
 254 {
 255         if (n >= 100*1000*1000)
 256                 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
 257         /* 1 <= n <= 1.6e11 */
 258         if (n >= 100*1000*1000)
 259                 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
 260         /* 1 <= n < 1e8 */
 261         return put_dec_trunc8(buf, n);
 262 }
 263
 264 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
 265
 266 static void
 267 put_dec_full4(char *buf, unsigned r)
 268 {
 269         unsigned q;
 270
 271         /* 0 <= r < 10^4 */
 272         q = (r * 0x147b) >> 19;
 273         *((u16 *)buf) = decpair[r - 100*q];
 274         buf += 2;
 275         /* 0 <= q < 100 */
 276         *((u16 *)buf) = decpair[q];
 277 }
 278
 279 /*
 280  * Call put_dec_full4 on x % 10000, return x / 10000.
 281  * The approximation x/10000 == (x * 0x346DC5D7) >> 43
 282  * holds for all x < 1,128,869,999.  The largest value this
 283  * helper will ever be asked to convert is 1,125,520,955.
 284  * (second call in the put_dec code, assuming n is all-ones).
 285  */
 286 static noinline_for_stack
 287 unsigned put_dec_helper4(char *buf, unsigned x)
 288 {
 289         uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
 290
 291         put_dec_full4(buf, x - q * 10000);
 292         return q;
 293 }
 294
 295 /* Based on code by Douglas W. Jones found at
 296  * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
 297  * (with permission from the author).
 298  * Performs no 64-bit division and hence should be fast on 32-bit machines.
 299  */
 300 static
 301 char *put_dec(char *buf, unsigned long long n)
 302 {
 303         uint32_t d3, d2, d1, q, h;
 304
 305         if (n < 100*1000*1000)
 306                 return put_dec_trunc8(buf, n);
 307
 308         d1  = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
 309         h   = (n >> 32);
 310         d2  = (h      ) & 0xffff;
 311         d3  = (h >> 16); /* implicit "& 0xffff" */
 312
 313         /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
 314              = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
 315         q   = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
 316         q = put_dec_helper4(buf, q);
 317
 318         q += 7671 * d3 + 9496 * d2 + 6 * d1;
 319         q = put_dec_helper4(buf+4, q);
 320
 321         q += 4749 * d3 + 42 * d2;
 322         q = put_dec_helper4(buf+8, q);
 323
 324         q += 281 * d3;
 325         buf += 12;
 326         if (q)
 327                 buf = put_dec_trunc8(buf, q);
 328         else while (buf[-1] == '0')
 329                 --buf;
 330
 331         return buf;
 332 }
 333
 334 #endif
 335
 336 /*
 337  * Convert passed number to decimal string.
 338  * Returns the length of string.  On buffer overflow, returns 0.
 339  *
 340  * If speed is not important, use snprintf(). It's easy to read the code.
 341  */
 342 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
 343 {
 344         /* put_dec requires 2-byte alignment of the buffer. */
 345         char tmp[sizeof(num) * 3] __aligned(2);
 346         int idx, len;
 347
 348         /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
 349         if (num <= 9) {
 350                 tmp[0] = '0' + num;
 351                 len = 1;
 352         } else {
 353                 len = put_dec(tmp, num) - tmp;
 354         }
 355
 356         if (len > size || width > size)
 357                 return 0;
 358
 359         if (width > len) {
 360                 width = width - len;
 361                 for (idx = 0; idx < width; idx++)
 362                         buf[idx] = ' ';
 363         } else {
 364                 width = 0;
 365         }
 366
 367         for (idx = 0; idx < len; ++idx)
 368                 buf[idx + width] = tmp[len - idx - 1];
 369
 370         return len + width;
 371 }
 372
 373 #define SIGN    1               /* unsigned/signed, must be 1 */
 374 #define LEFT    2               /* left justified */
 375 #define PLUS    4               /* show plus */
 376 #define SPACE   8               /* space if plus */
 377 #define ZEROPAD 16              /* pad with zero, must be 16 == '0' - ' ' */
 378 #define SMALL   32              /* use lowercase in hex (must be 32 == 0x20) */
 379 #define SPECIAL 64              /* prefix hex with "0x", octal with "0" */
 380
 381 enum format_type {
 382         FORMAT_TYPE_NONE, /* Just a string part */
 383         FORMAT_TYPE_WIDTH,
 384         FORMAT_TYPE_PRECISION,
 385         FORMAT_TYPE_CHAR,
 386         FORMAT_TYPE_STR,
 387         FORMAT_TYPE_PTR,
 388         FORMAT_TYPE_PERCENT_CHAR,
 389         FORMAT_TYPE_INVALID,
 390         FORMAT_TYPE_LONG_LONG,
 391         FORMAT_TYPE_ULONG,
 392         FORMAT_TYPE_LONG,
 393         FORMAT_TYPE_UBYTE,
 394         FORMAT_TYPE_BYTE,
 395         FORMAT_TYPE_USHORT,
 396         FORMAT_TYPE_SHORT,
 397         FORMAT_TYPE_UINT,
 398         FORMAT_TYPE_INT,
 399         FORMAT_TYPE_SIZE_T,
 400         FORMAT_TYPE_PTRDIFF
 401 };
 402
 403 struct printf_spec {
 404         unsigned int    type:8;         /* format_type enum */
 405         signed int      field_width:24; /* width of output field */
 406         unsigned int    flags:8;        /* flags to number() */
 407         unsigned int    base:8;         /* number base, 8, 10 or 16 only */
 408         signed int      precision:16;   /* # of digits/chars */
 409 } __packed;
 410 static_assert(sizeof(struct printf_spec) == 8);
 411
 412 #define FIELD_WIDTH_MAX ((1 << 23) - 1)
 413 #define PRECISION_MAX ((1 << 15) - 1)
 414
 415 static noinline_for_stack
 416 char *number(char *buf, char *end, unsigned long long num,
 417              struct printf_spec spec)
 418 {
 419         /* put_dec requires 2-byte alignment of the buffer. */
 420         char tmp[3 * sizeof(num)] __aligned(2);
 421         char sign;
 422         char locase;
 423         int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 424         int i;
 425         bool is_zero = num == 0LL;
 426         int field_width = spec.field_width;
 427         int precision = spec.precision;
 428
 429         /* locase = 0 or 0x20. ORing digits or letters with 'locase'
 430          * produces same digits or (maybe lowercased) letters */
 431         locase = (spec.flags & SMALL);
 432         if (spec.flags & LEFT)
 433                 spec.flags &= ~ZEROPAD;
 434         sign = 0;
 435         if (spec.flags & SIGN) {
 436                 if ((signed long long)num < 0) {
 437                         sign = '-';
 438                         num = -(signed long long)num;
 439                         field_width--;
 440                 } else if (spec.flags & PLUS) {
 441                         sign = '+';
 442                         field_width--;
 443                 } else if (spec.flags & SPACE) {
 444                         sign = ' ';
 445                         field_width--;
 446                 }
 447         }
 448         if (need_pfx) {
 449                 if (spec.base == 16)
 450                         field_width -= 2;
 451                 else if (!is_zero)
 452                         field_width--;
 453         }
 454
 455         /* generate full string in tmp[], in reverse order */
 456         i = 0;
 457         if (num < spec.base)
 458                 tmp[i++] = hex_asc_upper[num] | locase;
 459         else if (spec.base != 10) { /* 8 or 16 */
 460                 int mask = spec.base - 1;
 461                 int shift = 3;
 462
 463                 if (spec.base == 16)
 464                         shift = 4;
 465                 do {
 466                         tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
 467                         num >>= shift;
 468                 } while (num);
 469         } else { /* base 10 */
 470                 i = put_dec(tmp, num) - tmp;
 471         }
 472
 473         /* printing 100 using %2d gives "100", not "00" */
 474         if (i > precision)
 475                 precision = i;
 476         /* leading space padding */
 477         field_width -= precision;
 478         if (!(spec.flags & (ZEROPAD | LEFT))) {
 479                 while (--field_width >= 0) {
 480                         if (buf < end)
 481                                 *buf = ' ';
 482                         ++buf;
 483                 }
 484         }
 485         /* sign */
 486         if (sign) {
 487                 if (buf < end)
 488                         *buf = sign;
 489                 ++buf;
 490         }
 491         /* "0x" / "0" prefix */
 492         if (need_pfx) {
 493                 if (spec.base == 16 || !is_zero) {
 494                         if (buf < end)
 495                                 *buf = '0';
 496                         ++buf;
 497                 }
 498                 if (spec.base == 16) {
 499                         if (buf < end)
 500                                 *buf = ('X' | locase);
 501                         ++buf;
 502                 }
 503         }
 504         /* zero or space padding */
 505         if (!(spec.flags & LEFT)) {
 506                 char c = ' ' + (spec.flags & ZEROPAD);
 507                 BUILD_BUG_ON(' ' + ZEROPAD != '0');
 508                 while (--field_width >= 0) {
 509                         if (buf < end)
 510                                 *buf = c;
 511                         ++buf;
 512                 }
 513         }
 514         /* hmm even more zero padding? */
 515         while (i <= --precision) {
 516                 if (buf < end)
 517                         *buf = '0';
 518                 ++buf;
 519         }
 520         /* actual digits of result */
 521         while (--i >= 0) {
 522                 if (buf < end)
 523                         *buf = tmp[i];
 524                 ++buf;
 525         }
 526         /* trailing space padding */
 527         while (--field_width >= 0) {
 528                 if (buf < end)
 529                         *buf = ' ';
 530                 ++buf;
 531         }
 532
 533         return buf;
 534 }
 535
 536 static noinline_for_stack
 537 char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
 538 {
 539         struct printf_spec spec;
 540
 541         spec.type = FORMAT_TYPE_PTR;
 542         spec.field_width = 2 + 2 * size;        /* 0x + hex */
 543         spec.flags = SPECIAL | SMALL | ZEROPAD;
 544         spec.base = 16;
 545         spec.precision = -1;
 546
 547         return number(buf, end, num, spec);
 548 }
 549
 550 static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
 551 {
 552         size_t size;
 553         if (buf >= end) /* nowhere to put anything */
 554                 return;
 555         size = end - buf;
 556         if (size <= spaces) {
 557                 memset(buf, ' ', size);
 558                 return;
 559         }
 560         if (len) {
 561                 if (len > size - spaces)
 562                         len = size - spaces;
 563                 memmove(buf + spaces, buf, len);
 564         }
 565         memset(buf, ' ', spaces);
 566 }
 567
 568 /*
 569  * Handle field width padding for a string.
 570  * @buf: current buffer position
 571  * @n: length of string
 572  * @end: end of output buffer
 573  * @spec: for field width and flags
 574  * Returns: new buffer position after padding.
 575  */
 576 static noinline_for_stack
 577 char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
 578 {
 579         unsigned spaces;
 580
 581         if (likely(n >= spec.field_width))
 582                 return buf;
 583         /* we want to pad the sucker */
 584         spaces = spec.field_width - n;
 585         if (!(spec.flags & LEFT)) {
 586                 move_right(buf - n, end, n, spaces);
 587                 return buf + spaces;
 588         }
 589         while (spaces--) {
 590                 if (buf < end)
 591                         *buf = ' ';
 592                 ++buf;
 593         }
 594         return buf;
 595 }
 596
 597 /* Handle string from a well known address. */
 598 static char *string_nocheck(char *buf, char *end, const char *s,
 599                             struct printf_spec spec)
 600 {
 601         int len = 0;
 602         int lim = spec.precision;
 603
 604         while (lim--) {
 605                 char c = *s++;
 606                 if (!c)
 607                         break;
 608                 if (buf < end)
 609                         *buf = c;
 610                 ++buf;
 611                 ++len;
 612         }
 613         return widen_string(buf, len, end, spec);
 614 }
 615
 616 /* Be careful: error messages must fit into the given buffer. */
 617 static char *error_string(char *buf, char *end, const char *s,
 618                           struct printf_spec spec)
 619 {
 620         /*
 621          * Hard limit to avoid a completely insane messages. It actually
 622          * works pretty well because most error messages are in
 623          * the many pointer format modifiers.
 624          */
 625         if (spec.precision == -1)
 626                 spec.precision = 2 * sizeof(void *);
 627
 628         return string_nocheck(buf, end, s, spec);
 629 }
 630
 631 /*
 632  * Do not call any complex external code here. Nested printk()/vsprintf()
 633  * might cause infinite loops. Failures might break printk() and would
 634  * be hard to debug.
 635  */
 636 static const char *check_pointer_msg(const void *ptr)
 637 {
 638         if (!ptr)
 639                 return "(null)";
 640
 641         if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
 642                 return "(efault)";
 643
 644         return NULL;
 645 }
 646
 647 static int check_pointer(char **buf, char *end, const void *ptr,
 648                          struct printf_spec spec)
 649 {
 650         const char *err_msg;
 651
 652         err_msg = check_pointer_msg(ptr);
 653         if (err_msg) {
 654                 *buf = error_string(*buf, end, err_msg, spec);
 655                 return -EFAULT;
 656         }
 657
 658         return 0;
 659 }
 660
 661 static noinline_for_stack
 662 char *string(char *buf, char *end, const char *s,
 663              struct printf_spec spec)
 664 {
 665         if (check_pointer(&buf, end, s, spec))
 666                 return buf;
 667
 668         return string_nocheck(buf, end, s, spec);
 669 }
 670
 671 static char *pointer_string(char *buf, char *end,
 672                             const void *ptr,
 673                             struct printf_spec spec)
 674 {
 675         spec.base = 16;
 676         spec.flags |= SMALL;
 677         if (spec.field_width == -1) {
 678                 spec.field_width = 2 * sizeof(ptr);
 679                 spec.flags |= ZEROPAD;
 680         }
 681
 682         return number(buf, end, (unsigned long int)ptr, spec);
 683 }
 684
 685 /* Make pointers available for printing early in the boot sequence. */
 686 static int debug_boot_weak_hash __ro_after_init;
 687
 688 static int __init debug_boot_weak_hash_enable(char *str)
 689 {
 690         debug_boot_weak_hash = 1;
 691         pr_info("debug_boot_weak_hash enabled\n");
 692         return 0;
 693 }
 694 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
 695
 696 static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
 697 static siphash_key_t ptr_key __read_mostly;
 698
 699 static void enable_ptr_key_workfn(struct work_struct *work)
 700 {
 701         get_random_bytes(&ptr_key, sizeof(ptr_key));
 702         /* Needs to run from preemptible context */
 703         static_branch_disable(&not_filled_random_ptr_key);
 704 }
 705
 706 static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
 707
 708 static void fill_random_ptr_key(struct random_ready_callback *unused)
 709 {
 710         /* This may be in an interrupt handler. */
 711         queue_work(system_unbound_wq, &enable_ptr_key_work);
 712 }
 713
 714 static struct random_ready_callback random_ready = {
 715         .func = fill_random_ptr_key
 716 };
 717
 718 static int __init initialize_ptr_random(void)
 719 {
 720         int key_size = sizeof(ptr_key);
 721         int ret;
 722
 723         /* Use hw RNG if available. */
 724         if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
 725                 static_branch_disable(&not_filled_random_ptr_key);
 726                 return 0;
 727         }
 728
 729         ret = add_random_ready_callback(&random_ready);
 730         if (!ret) {
 731                 return 0;
 732         } else if (ret == -EALREADY) {
 733                 /* This is in preemptible context */
 734                 enable_ptr_key_workfn(&enable_ptr_key_work);
 735                 return 0;
 736         }
 737
 738         return ret;
 739 }
 740 early_initcall(initialize_ptr_random);
 741
 742 /* Maps a pointer to a 32 bit unique identifier. */
 743 static char *ptr_to_id(char *buf, char *end, const void *ptr,
 744                        struct printf_spec spec)
 745 {
 746         const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
 747         unsigned long hashval;
 748
 749         /* When debugging early boot use non-cryptographically secure hash. */
 750         if (unlikely(debug_boot_weak_hash)) {
 751                 hashval = hash_long((unsigned long)ptr, 32);
 752                 return pointer_string(buf, end, (const void *)hashval, spec);
 753         }
 754
 755         if (static_branch_unlikely(&not_filled_random_ptr_key)) {
 756                 spec.field_width = 2 * sizeof(ptr);
 757                 /* string length must be less than default_width */
 758                 return error_string(buf, end, str, spec);
 759         }
 760
 761 #ifdef CONFIG_64BIT
 762         hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
 763         /*
 764          * Mask off the first 32 bits, this makes explicit that we have
 765          * modified the address (and 32 bits is plenty for a unique ID).
 766          */
 767         hashval = hashval & 0xffffffff;
 768 #else
 769         hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
 770 #endif
 771         return pointer_string(buf, end, (const void *)hashval, spec);
 772 }
 773
 774 int kptr_restrict __read_mostly;
 775
 776 static noinline_for_stack
 777 char *restricted_pointer(char *buf, char *end, const void *ptr,
 778                          struct printf_spec spec)
 779 {
 780         switch (kptr_restrict) {
 781         case 0:
 782                 /* Handle as %p, hash and do _not_ leak addresses. */
 783                 return ptr_to_id(buf, end, ptr, spec);
 784         case 1: {
 785                 const struct cred *cred;
 786
 787                 /*
 788                  * kptr_restrict==1 cannot be used in IRQ context
 789                  * because its test for CAP_SYSLOG would be meaningless.
 790                  */
 791                 if (in_irq() || in_serving_softirq() || in_nmi()) {
 792                         if (spec.field_width == -1)
 793                                 spec.field_width = 2 * sizeof(ptr);
 794                         return error_string(buf, end, "pK-error", spec);
 795                 }
 796
 797                 /*
 798                  * Only print the real pointer value if the current
 799                  * process has CAP_SYSLOG and is running with the
 800                  * same credentials it started with. This is because
 801                  * access to files is checked at open() time, but %pK
 802                  * checks permission at read() time. We don't want to
 803                  * leak pointer values if a binary opens a file using
 804                  * %pK and then elevates privileges before reading it.
 805                  */
 806                 cred = current_cred();
 807                 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
 808                     !uid_eq(cred->euid, cred->uid) ||
 809                     !gid_eq(cred->egid, cred->gid))
 810                         ptr = NULL;
 811                 break;
 812         }
 813         case 2:
 814         default:
 815                 /* Always print 0's for %pK */
 816                 ptr = NULL;
 817                 break;
 818         }
 819
 820         return pointer_string(buf, end, ptr, spec);
 821 }
 822
 823 static noinline_for_stack
 824 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
 825                   const char *fmt)
 826 {
 827         const char *array[4], *s;
 828         const struct dentry *p;
 829         int depth;
 830         int i, n;
 831
 832         switch (fmt[1]) {
 833                 case '2': case '3': case '4':
 834                         depth = fmt[1] - '0';
 835                         break;
 836                 default:
 837                         depth = 1;
 838         }
 839
 840         rcu_read_lock();
 841         for (i = 0; i < depth; i++, d = p) {
 842                 if (check_pointer(&buf, end, d, spec)) {
 843                         rcu_read_unlock();
 844                         return buf;
 845                 }
 846
 847                 p = READ_ONCE(d->d_parent);
 848                 array[i] = READ_ONCE(d->d_name.name);
 849                 if (p == d) {
 850                         if (i)
 851                                 array[i] = "";
 852                         i++;
 853                         break;
 854                 }
 855         }
 856         s = array[--i];
 857         for (n = 0; n != spec.precision; n++, buf++) {
 858                 char c = *s++;
 859                 if (!c) {
 860                         if (!i)
 861                                 break;
 862                         c = '/';
 863                         s = array[--i];
 864                 }
 865                 if (buf < end)
 866                         *buf = c;
 867         }
 868         rcu_read_unlock();
 869         return widen_string(buf, n, end, spec);
 870 }
 871
 872 static noinline_for_stack
 873 char *file_dentry_name(char *buf, char *end, const struct file *f,
 874                         struct printf_spec spec, const char *fmt)
 875 {
 876         if (check_pointer(&buf, end, f, spec))
 877                 return buf;
 878
 879         return dentry_name(buf, end, f->f_path.dentry, spec, fmt);
 880 }
 881 #ifdef CONFIG_BLOCK
 882 static noinline_for_stack
 883 char *bdev_name(char *buf, char *end, struct block_device *bdev,
 884                 struct printf_spec spec, const char *fmt)
 885 {
 886         struct gendisk *hd;
 887
 888         if (check_pointer(&buf, end, bdev, spec))
 889                 return buf;
 890
 891         hd = bdev->bd_disk;
 892         buf = string(buf, end, hd->disk_name, spec);
 893         if (bdev->bd_part->partno) {
 894                 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
 895                         if (buf < end)
 896                                 *buf = 'p';
 897                         buf++;
 898                 }
 899                 buf = number(buf, end, bdev->bd_part->partno, spec);
 900         }
 901         return buf;
 902 }
 903 #endif
 904
 905 static noinline_for_stack
 906 char *symbol_string(char *buf, char *end, void *ptr,
 907                     struct printf_spec spec, const char *fmt)
 908 {
 909         unsigned long value;
 910 #ifdef CONFIG_KALLSYMS
 911         char sym[KSYM_SYMBOL_LEN];
 912 #endif
 913
 914         if (fmt[1] == 'R')
 915                 ptr = __builtin_extract_return_addr(ptr);
 916         value = (unsigned long)ptr;
 917
 918 #ifdef CONFIG_KALLSYMS
 919         if (*fmt == 'B')
 920                 sprint_backtrace(sym, value);
 921         else if (*fmt != 'f' && *fmt != 's')
 922                 sprint_symbol(sym, value);
 923         else
 924                 sprint_symbol_no_offset(sym, value);
 925
 926         return string_nocheck(buf, end, sym, spec);
 927 #else
 928         return special_hex_number(buf, end, value, sizeof(void *));
 929 #endif
 930 }
 931
 932 static const struct printf_spec default_str_spec = {
 933         .field_width = -1,
 934         .precision = -1,
 935 };
 936
 937 static const struct printf_spec default_flag_spec = {
 938         .base = 16,
 939         .precision = -1,
 940         .flags = SPECIAL | SMALL,
 941 };
 942
 943 static const struct printf_spec default_dec_spec = {
 944         .base = 10,
 945         .precision = -1,
 946 };
 947
 948 static const struct printf_spec default_dec02_spec = {
 949         .base = 10,
 950         .field_width = 2,
 951         .precision = -1,
 952         .flags = ZEROPAD,
 953 };
 954
 955 static const struct printf_spec default_dec04_spec = {
 956         .base = 10,
 957         .field_width = 4,
 958         .precision = -1,
 959         .flags = ZEROPAD,
 960 };
 961
 962 static noinline_for_stack
 963 char *resource_string(char *buf, char *end, struct resource *res,
 964                       struct printf_spec spec, const char *fmt)
 965 {
 966 #ifndef IO_RSRC_PRINTK_SIZE
 967 #define IO_RSRC_PRINTK_SIZE     6
 968 #endif
 969
 970 #ifndef MEM_RSRC_PRINTK_SIZE
 971 #define MEM_RSRC_PRINTK_SIZE    10
 972 #endif
 973         static const struct printf_spec io_spec = {
 974                 .base = 16,
 975                 .field_width = IO_RSRC_PRINTK_SIZE,
 976                 .precision = -1,
 977                 .flags = SPECIAL | SMALL | ZEROPAD,
 978         };
 979         static const struct printf_spec mem_spec = {
 980                 .base = 16,
 981                 .field_width = MEM_RSRC_PRINTK_SIZE,
 982                 .precision = -1,
 983                 .flags = SPECIAL | SMALL | ZEROPAD,
 984         };
 985         static const struct printf_spec bus_spec = {
 986                 .base = 16,
 987                 .field_width = 2,
 988                 .precision = -1,
 989                 .flags = SMALL | ZEROPAD,
 990         };
 991         static const struct printf_spec str_spec = {
 992                 .field_width = -1,
 993                 .precision = 10,
 994                 .flags = LEFT,
 995         };
 996
 997         /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
 998          * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
 999 #define RSRC_BUF_SIZE           ((2 * sizeof(resource_size_t)) + 4)
1000 #define FLAG_BUF_SIZE           (2 * sizeof(res->flags))
1001 #define DECODED_BUF_SIZE        sizeof("[mem - 64bit pref window disabled]")
1002 #define RAW_BUF_SIZE            sizeof("[mem - flags 0x]")
1003         char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
1004                      2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
1005
1006         char *p = sym, *pend = sym + sizeof(sym);
1007         int decode = (fmt[0] == 'R') ? 1 : 0;
1008         const struct printf_spec *specp;
1009
1010         if (check_pointer(&buf, end, res, spec))
1011                 return buf;
1012
1013         *p++ = '[';
1014         if (res->flags & IORESOURCE_IO) {
1015                 p = string_nocheck(p, pend, "io  ", str_spec);
1016                 specp = &io_spec;
1017         } else if (res->flags & IORESOURCE_MEM) {
1018                 p = string_nocheck(p, pend, "mem ", str_spec);
1019                 specp = &mem_spec;
1020         } else if (res->flags & IORESOURCE_IRQ) {
1021                 p = string_nocheck(p, pend, "irq ", str_spec);
1022                 specp = &default_dec_spec;
1023         } else if (res->flags & IORESOURCE_DMA) {
1024                 p = string_nocheck(p, pend, "dma ", str_spec);
1025                 specp = &default_dec_spec;
1026         } else if (res->flags & IORESOURCE_BUS) {
1027                 p = string_nocheck(p, pend, "bus ", str_spec);
1028                 specp = &bus_spec;
1029         } else {
1030                 p = string_nocheck(p, pend, "??? ", str_spec);
1031                 specp = &mem_spec;
1032                 decode = 0;
1033         }
1034         if (decode && res->flags & IORESOURCE_UNSET) {
1035                 p = string_nocheck(p, pend, "size ", str_spec);
1036                 p = number(p, pend, resource_size(res), *specp);
1037         } else {
1038                 p = number(p, pend, res->start, *specp);
1039                 if (res->start != res->end) {
1040                         *p++ = '-';
1041                         p = number(p, pend, res->end, *specp);
1042                 }
1043         }
1044         if (decode) {
1045                 if (res->flags & IORESOURCE_MEM_64)
1046                         p = string_nocheck(p, pend, " 64bit", str_spec);
1047                 if (res->flags & IORESOURCE_PREFETCH)
1048                         p = string_nocheck(p, pend, " pref", str_spec);
1049                 if (res->flags & IORESOURCE_WINDOW)
1050                         p = string_nocheck(p, pend, " window", str_spec);
1051                 if (res->flags & IORESOURCE_DISABLED)
1052                         p = string_nocheck(p, pend, " disabled", str_spec);
1053         } else {
1054                 p = string_nocheck(p, pend, " flags ", str_spec);
1055                 p = number(p, pend, res->flags, default_flag_spec);
1056         }
1057         *p++ = ']';
1058         *p = '\0';
1059
1060         return string_nocheck(buf, end, sym, spec);
1061 }
1062
1063 static noinline_for_stack
1064 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1065                  const char *fmt)
1066 {
1067         int i, len = 1;         /* if we pass '%ph[CDN]', field width remains
1068                                    negative value, fallback to the default */
1069         char separator;
1070
1071         if (spec.field_width == 0)
1072                 /* nothing to print */
1073                 return buf;
1074
1075         if (check_pointer(&buf, end, addr, spec))
1076                 return buf;
1077
1078         switch (fmt[1]) {
1079         case 'C':
1080                 separator = ':';
1081                 break;
1082         case 'D':
1083                 separator = '-';
1084                 break;
1085         case 'N':
1086                 separator = 0;
1087                 break;
1088         default:
1089                 separator = ' ';
1090                 break;
1091         }
1092
1093         if (spec.field_width > 0)
1094                 len = min_t(int, spec.field_width, 64);
1095
1096         for (i = 0; i < len; ++i) {
1097                 if (buf < end)
1098                         *buf = hex_asc_hi(addr[i]);
1099                 ++buf;
1100                 if (buf < end)
1101                         *buf = hex_asc_lo(addr[i]);
1102                 ++buf;
1103
1104                 if (separator && i != len - 1) {
1105                         if (buf < end)
1106                                 *buf = separator;
1107                         ++buf;
1108                 }
1109         }
1110
1111         return buf;
1112 }
1113
1114 static noinline_for_stack
1115 char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
1116                     struct printf_spec spec, const char *fmt)
1117 {
1118         const int CHUNKSZ = 32;
1119         int nr_bits = max_t(int, spec.field_width, 0);
1120         int i, chunksz;
1121         bool first = true;
1122
1123         if (check_pointer(&buf, end, bitmap, spec))
1124                 return buf;
1125
1126         /* reused to print numbers */
1127         spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
1128
1129         chunksz = nr_bits & (CHUNKSZ - 1);
1130         if (chunksz == 0)
1131                 chunksz = CHUNKSZ;
1132
1133         i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
1134         for (; i >= 0; i -= CHUNKSZ) {
1135                 u32 chunkmask, val;
1136                 int word, bit;
1137
1138                 chunkmask = ((1ULL << chunksz) - 1);
1139                 word = i / BITS_PER_LONG;
1140                 bit = i % BITS_PER_LONG;
1141                 val = (bitmap[word] >> bit) & chunkmask;
1142
1143                 if (!first) {
1144                         if (buf < end)
1145                                 *buf = ',';
1146                         buf++;
1147                 }
1148                 first = false;
1149
1150                 spec.field_width = DIV_ROUND_UP(chunksz, 4);
1151                 buf = number(buf, end, val, spec);
1152
1153                 chunksz = CHUNKSZ;
1154         }
1155         return buf;
1156 }
1157
1158 static noinline_for_stack
1159 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
1160                          struct printf_spec spec, const char *fmt)
1161 {
1162         int nr_bits = max_t(int, spec.field_width, 0);
1163         /* current bit is 'cur', most recently seen range is [rbot, rtop] */
1164         int cur, rbot, rtop;
1165         bool first = true;
1166
1167         if (check_pointer(&buf, end, bitmap, spec))
1168                 return buf;
1169
1170         rbot = cur = find_first_bit(bitmap, nr_bits);
1171         while (cur < nr_bits) {
1172                 rtop = cur;
1173                 cur = find_next_bit(bitmap, nr_bits, cur + 1);
1174                 if (cur < nr_bits && cur <= rtop + 1)
1175                         continue;
1176
1177                 if (!first) {
1178                         if (buf < end)
1179                                 *buf = ',';
1180                         buf++;
1181                 }
1182                 first = false;
1183
1184                 buf = number(buf, end, rbot, default_dec_spec);
1185                 if (rbot < rtop) {
1186                         if (buf < end)
1187                                 *buf = '-';
1188                         buf++;
1189
1190                         buf = number(buf, end, rtop, default_dec_spec);
1191                 }
1192
1193                 rbot = cur;
1194         }
1195         return buf;
1196 }
1197
1198 static noinline_for_stack
1199 char *mac_address_string(char *buf, char *end, u8 *addr,
1200                          struct printf_spec spec, const char *fmt)
1201 {
1202         char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
1203         char *p = mac_addr;
1204         int i;
1205         char separator;
1206         bool reversed = false;
1207
1208         if (check_pointer(&buf, end, addr, spec))
1209                 return buf;
1210
1211         switch (fmt[1]) {
1212         case 'F':
1213                 separator = '-';
1214                 break;
1215
1216         case 'R':
1217                 reversed = true;
1218                 /* fall through */
1219
1220         default:
1221                 separator = ':';
1222                 break;
1223         }
1224
1225         for (i = 0; i < 6; i++) {
1226                 if (reversed)
1227                         p = hex_byte_pack(p, addr[5 - i]);
1228                 else
1229                         p = hex_byte_pack(p, addr[i]);
1230
1231                 if (fmt[0] == 'M' && i != 5)
1232                         *p++ = separator;
1233         }
1234         *p = '\0';
1235
1236         return string_nocheck(buf, end, mac_addr, spec);
1237 }
1238
1239 static noinline_for_stack
1240 char *ip4_string(char *p, const u8 *addr, const char *fmt)
1241 {
1242         int i;
1243         bool leading_zeros = (fmt[0] == 'i');
1244         int index;
1245         int step;
1246
1247         switch (fmt[2]) {
1248         case 'h':
1249 #ifdef __BIG_ENDIAN
1250                 index = 0;
1251                 step = 1;
1252 #else
1253                 index = 3;
1254                 step = -1;
1255 #endif
1256                 break;
1257         case 'l':
1258                 index = 3;
1259                 step = -1;
1260                 break;
1261         case 'n':
1262         case 'b':
1263         default:
1264                 index = 0;
1265                 step = 1;
1266                 break;
1267         }
1268         for (i = 0; i < 4; i++) {
1269                 char temp[4] __aligned(2);      /* hold each IP quad in reverse order */
1270                 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1271                 if (leading_zeros) {
1272                         if (digits < 3)
1273                                 *p++ = '0';
1274                         if (digits < 2)
1275                                 *p++ = '0';
1276                 }
1277                 /* reverse the digits in the quad */
1278                 while (digits--)
1279                         *p++ = temp[digits];
1280                 if (i < 3)
1281                         *p++ = '.';
1282                 index += step;
1283         }
1284         *p = '\0';
1285
1286         return p;
1287 }
1288
1289 static noinline_for_stack
1290 char *ip6_compressed_string(char *p, const char *addr)
1291 {
1292         int i, j, range;
1293         unsigned char zerolength[8];
1294         int longest = 1;
1295         int colonpos = -1;
1296         u16 word;
1297         u8 hi, lo;
1298         bool needcolon = false;
1299         bool useIPv4;
1300         struct in6_addr in6;
1301
1302         memcpy(&in6, addr, sizeof(struct in6_addr));
1303
1304         useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1305
1306         memset(zerolength, 0, sizeof(zerolength));
1307
1308         if (useIPv4)
1309                 range = 6;
1310         else
1311                 range = 8;
1312
1313         /* find position of longest 0 run */
1314         for (i = 0; i < range; i++) {
1315                 for (j = i; j < range; j++) {
1316                         if (in6.s6_addr16[j] != 0)
1317                                 break;
1318                         zerolength[i]++;
1319                 }
1320         }
1321         for (i = 0; i < range; i++) {
1322                 if (zerolength[i] > longest) {
1323                         longest = zerolength[i];
1324                         colonpos = i;
1325                 }
1326         }
1327         if (longest == 1)               /* don't compress a single 0 */
1328                 colonpos = -1;
1329
1330         /* emit address */
1331         for (i = 0; i < range; i++) {
1332                 if (i == colonpos) {
1333                         if (needcolon || i == 0)
1334                                 *p++ = ':';
1335                         *p++ = ':';
1336                         needcolon = false;
1337                         i += longest - 1;
1338                         continue;
1339                 }
1340                 if (needcolon) {
1341                         *p++ = ':';
1342                         needcolon = false;
1343                 }
1344                 /* hex u16 without leading 0s */
1345                 word = ntohs(in6.s6_addr16[i]);
1346                 hi = word >> 8;
1347                 lo = word & 0xff;
1348                 if (hi) {
1349                         if (hi > 0x0f)
1350                                 p = hex_byte_pack(p, hi);
1351                         else
1352                                 *p++ = hex_asc_lo(hi);
1353                         p = hex_byte_pack(p, lo);
1354                 }
1355                 else if (lo > 0x0f)
1356                         p = hex_byte_pack(p, lo);
1357                 else
1358                         *p++ = hex_asc_lo(lo);
1359                 needcolon = true;
1360         }
1361
1362         if (useIPv4) {
1363                 if (needcolon)
1364                         *p++ = ':';
1365                 p = ip4_string(p, &in6.s6_addr[12], "I4");
1366         }
1367         *p = '\0';
1368
1369         return p;
1370 }
1371
1372 static noinline_for_stack
1373 char *ip6_string(char *p, const char *addr, const char *fmt)
1374 {
1375         int i;
1376
1377         for (i = 0; i < 8; i++) {
1378                 p = hex_byte_pack(p, *addr++);
1379                 p = hex_byte_pack(p, *addr++);
1380                 if (fmt[0] == 'I' && i != 7)
1381                         *p++ = ':';
1382         }
1383         *p = '\0';
1384
1385         return p;
1386 }
1387
1388 static noinline_for_stack
1389 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1390                       struct printf_spec spec, const char *fmt)
1391 {
1392         char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1393
1394         if (fmt[0] == 'I' && fmt[2] == 'c')
1395                 ip6_compressed_string(ip6_addr, addr);
1396         else
1397                 ip6_string(ip6_addr, addr, fmt);
1398
1399         return string_nocheck(buf, end, ip6_addr, spec);
1400 }
1401
1402 static noinline_for_stack
1403 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1404                       struct printf_spec spec, const char *fmt)
1405 {
1406         char ip4_addr[sizeof("255.255.255.255")];
1407
1408         ip4_string(ip4_addr, addr, fmt);
1409
1410         return string_nocheck(buf, end, ip4_addr, spec);
1411 }
1412
1413 static noinline_for_stack
1414 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1415                          struct printf_spec spec, const char *fmt)
1416 {
1417         bool have_p = false, have_s = false, have_f = false, have_c = false;
1418         char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1419                       sizeof(":12345") + sizeof("/123456789") +
1420                       sizeof("%1234567890")];
1421         char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1422         const u8 *addr = (const u8 *) &sa->sin6_addr;
1423         char fmt6[2] = { fmt[0], '6' };
1424         u8 off = 0;
1425
1426         fmt++;
1427         while (isalpha(*++fmt)) {
1428                 switch (*fmt) {
1429                 case 'p':
1430                         have_p = true;
1431                         break;
1432                 case 'f':
1433                         have_f = true;
1434                         break;
1435                 case 's':
1436                         have_s = true;
1437                         break;
1438                 case 'c':
1439                         have_c = true;
1440                         break;
1441                 }
1442         }
1443
1444         if (have_p || have_s || have_f) {
1445                 *p = '[';
1446                 off = 1;
1447         }
1448
1449         if (fmt6[0] == 'I' && have_c)
1450                 p = ip6_compressed_string(ip6_addr + off, addr);
1451         else
1452                 p = ip6_string(ip6_addr + off, addr, fmt6);
1453
1454         if (have_p || have_s || have_f)
1455                 *p++ = ']';
1456
1457         if (have_p) {
1458                 *p++ = ':';
1459                 p = number(p, pend, ntohs(sa->sin6_port), spec);
1460         }
1461         if (have_f) {
1462                 *p++ = '/';
1463                 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1464                                           IPV6_FLOWINFO_MASK), spec);
1465         }
1466         if (have_s) {
1467                 *p++ = '%';
1468                 p = number(p, pend, sa->sin6_scope_id, spec);
1469         }
1470         *p = '\0';
1471
1472         return string_nocheck(buf, end, ip6_addr, spec);
1473 }
1474
1475 static noinline_for_stack
1476 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1477                          struct printf_spec spec, const char *fmt)
1478 {
1479         bool have_p = false;
1480         char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1481         char *pend = ip4_addr + sizeof(ip4_addr);
1482         const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1483         char fmt4[3] = { fmt[0], '4', 0 };
1484
1485         fmt++;
1486         while (isalpha(*++fmt)) {
1487                 switch (*fmt) {
1488                 case 'p':
1489                         have_p = true;
1490                         break;
1491                 case 'h':
1492                 case 'l':
1493                 case 'n':
1494                 case 'b':
1495                         fmt4[2] = *fmt;
1496                         break;
1497                 }
1498         }
1499
1500         p = ip4_string(ip4_addr, addr, fmt4);
1501         if (have_p) {
1502                 *p++ = ':';
1503                 p = number(p, pend, ntohs(sa->sin_port), spec);
1504         }
1505         *p = '\0';
1506
1507         return string_nocheck(buf, end, ip4_addr, spec);
1508 }
1509
1510 static noinline_for_stack
1511 char *ip_addr_string(char *buf, char *end, const void *ptr,
1512                      struct printf_spec spec, const char *fmt)
1513 {
1514         char *err_fmt_msg;
1515
1516         if (check_pointer(&buf, end, ptr, spec))
1517                 return buf;
1518
1519         switch (fmt[1]) {
1520         case '6':
1521                 return ip6_addr_string(buf, end, ptr, spec, fmt);
1522         case '4':
1523                 return ip4_addr_string(buf, end, ptr, spec, fmt);
1524         case 'S': {
1525                 const union {
1526                         struct sockaddr         raw;
1527                         struct sockaddr_in      v4;
1528                         struct sockaddr_in6     v6;
1529                 } *sa = ptr;
1530
1531                 switch (sa->raw.sa_family) {
1532                 case AF_INET:
1533                         return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1534                 case AF_INET6:
1535                         return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1536                 default:
1537                         return error_string(buf, end, "(einval)", spec);
1538                 }}
1539         }
1540
1541         err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
1542         return error_string(buf, end, err_fmt_msg, spec);
1543 }
1544
1545 static noinline_for_stack
1546 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1547                      const char *fmt)
1548 {
1549         bool found = true;
1550         int count = 1;
1551         unsigned int flags = 0;
1552         int len;
1553
1554         if (spec.field_width == 0)
1555                 return buf;                             /* nothing to print */
1556
1557         if (check_pointer(&buf, end, addr, spec))
1558                 return buf;
1559
1560         do {
1561                 switch (fmt[count++]) {
1562                 case 'a':
1563                         flags |= ESCAPE_ANY;
1564                         break;
1565                 case 'c':
1566                         flags |= ESCAPE_SPECIAL;
1567                         break;
1568                 case 'h':
1569                         flags |= ESCAPE_HEX;
1570                         break;
1571                 case 'n':
1572                         flags |= ESCAPE_NULL;
1573                         break;
1574                 case 'o':
1575                         flags |= ESCAPE_OCTAL;
1576                         break;
1577                 case 'p':
1578                         flags |= ESCAPE_NP;
1579                         break;
1580                 case 's':
1581                         flags |= ESCAPE_SPACE;
1582                         break;
1583                 default:
1584                         found = false;
1585                         break;
1586                 }
1587         } while (found);
1588
1589         if (!flags)
1590                 flags = ESCAPE_ANY_NP;
1591
1592         len = spec.field_width < 0 ? 1 : spec.field_width;
1593
1594         /*
1595          * string_escape_mem() writes as many characters as it can to
1596          * the given buffer, and returns the total size of the output
1597          * had the buffer been big enough.
1598          */
1599         buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1600
1601         return buf;
1602 }
1603
1604 static char *va_format(char *buf, char *end, struct va_format *va_fmt,
1605                        struct printf_spec spec, const char *fmt)
1606 {
1607         va_list va;
1608
1609         if (check_pointer(&buf, end, va_fmt, spec))
1610                 return buf;
1611
1612         va_copy(va, *va_fmt->va);
1613         buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
1614         va_end(va);
1615
1616         return buf;
1617 }
1618
1619 static noinline_for_stack
1620 char *uuid_string(char *buf, char *end, const u8 *addr,
1621                   struct printf_spec spec, const char *fmt)
1622 {
1623         char uuid[UUID_STRING_LEN + 1];
1624         char *p = uuid;
1625         int i;
1626         const u8 *index = uuid_index;
1627         bool uc = false;
1628
1629         if (check_pointer(&buf, end, addr, spec))
1630                 return buf;
1631
1632         switch (*(++fmt)) {
1633         case 'L':
1634                 uc = true;              /* fall-through */
1635         case 'l':
1636                 index = guid_index;
1637                 break;
1638         case 'B':
1639                 uc = true;
1640                 break;
1641         }
1642
1643         for (i = 0; i < 16; i++) {
1644                 if (uc)
1645                         p = hex_byte_pack_upper(p, addr[index[i]]);
1646                 else
1647                         p = hex_byte_pack(p, addr[index[i]]);
1648                 switch (i) {
1649                 case 3:
1650                 case 5:
1651                 case 7:
1652                 case 9:
1653                         *p++ = '-';
1654                         break;
1655                 }
1656         }
1657
1658         *p = 0;
1659
1660         return string_nocheck(buf, end, uuid, spec);
1661 }
1662
1663 static noinline_for_stack
1664 char *netdev_bits(char *buf, char *end, const void *addr,
1665                   struct printf_spec spec,  const char *fmt)
1666 {
1667         unsigned long long num;
1668         int size;
1669
1670         if (check_pointer(&buf, end, addr, spec))
1671                 return buf;
1672
1673         switch (fmt[1]) {
1674         case 'F':
1675                 num = *(const netdev_features_t *)addr;
1676                 size = sizeof(netdev_features_t);
1677                 break;
1678         default:
1679                 return error_string(buf, end, "(%pN?)", spec);
1680         }
1681
1682         return special_hex_number(buf, end, num, size);
1683 }
1684
1685 static noinline_for_stack
1686 char *address_val(char *buf, char *end, const void *addr,
1687                   struct printf_spec spec, const char *fmt)
1688 {
1689         unsigned long long num;
1690         int size;
1691
1692         if (check_pointer(&buf, end, addr, spec))
1693                 return buf;
1694
1695         switch (fmt[1]) {
1696         case 'd':
1697                 num = *(const dma_addr_t *)addr;
1698                 size = sizeof(dma_addr_t);
1699                 break;
1700         case 'p':
1701         default:
1702                 num = *(const phys_addr_t *)addr;
1703                 size = sizeof(phys_addr_t);
1704                 break;
1705         }
1706
1707         return special_hex_number(buf, end, num, size);
1708 }
1709
1710 static noinline_for_stack
1711 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1712 {
1713         int year = tm->tm_year + (r ? 0 : 1900);
1714         int mon = tm->tm_mon + (r ? 0 : 1);
1715
1716         buf = number(buf, end, year, default_dec04_spec);
1717         if (buf < end)
1718                 *buf = '-';
1719         buf++;
1720
1721         buf = number(buf, end, mon, default_dec02_spec);
1722         if (buf < end)
1723                 *buf = '-';
1724         buf++;
1725
1726         return number(buf, end, tm->tm_mday, default_dec02_spec);
1727 }
1728
1729 static noinline_for_stack
1730 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1731 {
1732         buf = number(buf, end, tm->tm_hour, default_dec02_spec);
1733         if (buf < end)
1734                 *buf = ':';
1735         buf++;
1736
1737         buf = number(buf, end, tm->tm_min, default_dec02_spec);
1738         if (buf < end)
1739                 *buf = ':';
1740         buf++;
1741
1742         return number(buf, end, tm->tm_sec, default_dec02_spec);
1743 }
1744
1745 static noinline_for_stack
1746 char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
1747               struct printf_spec spec, const char *fmt)
1748 {
1749         bool have_t = true, have_d = true;
1750         bool raw = false;
1751         int count = 2;
1752
1753         if (check_pointer(&buf, end, tm, spec))
1754                 return buf;
1755
1756         switch (fmt[count]) {
1757         case 'd':
1758                 have_t = false;
1759                 count++;
1760                 break;
1761         case 't':
1762                 have_d = false;
1763                 count++;
1764                 break;
1765         }
1766
1767         raw = fmt[count] == 'r';
1768
1769         if (have_d)
1770                 buf = date_str(buf, end, tm, raw);
1771         if (have_d && have_t) {
1772                 /* Respect ISO 8601 */
1773                 if (buf < end)
1774                         *buf = 'T';
1775                 buf++;
1776         }
1777         if (have_t)
1778                 buf = time_str(buf, end, tm, raw);
1779
1780         return buf;
1781 }
1782
1783 static noinline_for_stack
1784 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
1785                     const char *fmt)
1786 {
1787         switch (fmt[1]) {
1788         case 'R':
1789                 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
1790         default:
1791                 return error_string(buf, end, "(%ptR?)", spec);
1792         }
1793 }
1794
1795 static noinline_for_stack
1796 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1797             const char *fmt)
1798 {
1799         if (!IS_ENABLED(CONFIG_HAVE_CLK))
1800                 return error_string(buf, end, "(%pC?)", spec);
1801
1802         if (check_pointer(&buf, end, clk, spec))
1803                 return buf;
1804
1805         switch (fmt[1]) {
1806         case 'n':
1807         default:
1808 #ifdef CONFIG_COMMON_CLK
1809                 return string(buf, end, __clk_get_name(clk), spec);
1810 #else
1811                 return ptr_to_id(buf, end, clk, spec);
1812 #endif
1813         }
1814 }
1815
1816 static
1817 char *format_flags(char *buf, char *end, unsigned long flags,
1818                                         const struct trace_print_flags *names)
1819 {
1820         unsigned long mask;
1821
1822         for ( ; flags && names->name; names++) {
1823                 mask = names->mask;
1824                 if ((flags & mask) != mask)
1825                         continue;
1826
1827                 buf = string(buf, end, names->name, default_str_spec);
1828
1829                 flags &= ~mask;
1830                 if (flags) {
1831                         if (buf < end)
1832                                 *buf = '|';
1833                         buf++;
1834                 }
1835         }
1836
1837         if (flags)
1838                 buf = number(buf, end, flags, default_flag_spec);
1839
1840         return buf;
1841 }
1842
1843 static noinline_for_stack
1844 char *flags_string(char *buf, char *end, void *flags_ptr,
1845                    struct printf_spec spec, const char *fmt)
1846 {
1847         unsigned long flags;
1848         const struct trace_print_flags *names;
1849
1850         if (check_pointer(&buf, end, flags_ptr, spec))
1851                 return buf;
1852
1853         switch (fmt[1]) {
1854         case 'p':
1855                 flags = *(unsigned long *)flags_ptr;
1856                 /* Remove zone id */
1857                 flags &= (1UL << NR_PAGEFLAGS) - 1;
1858                 names = pageflag_names;
1859                 break;
1860         case 'v':
1861                 flags = *(unsigned long *)flags_ptr;
1862                 names = vmaflag_names;
1863                 break;
1864         case 'g':
1865                 flags = *(gfp_t *)flags_ptr;
1866                 names = gfpflag_names;
1867                 break;
1868         default:
1869                 return error_string(buf, end, "(%pG?)", spec);
1870         }
1871
1872         return format_flags(buf, end, flags, names);
1873 }
1874
1875 static const char *device_node_name_for_depth(const struct device_node *np, int depth)
1876 {
1877         for ( ; np && depth; depth--)
1878                 np = np->parent;
1879
1880         return kbasename(np->full_name);
1881 }
1882
1883 static noinline_for_stack
1884 char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end)
1885 {
1886         int depth;
1887         const struct device_node *parent = np->parent;
1888
1889         /* special case for root node */
1890         if (!parent)
1891                 return string_nocheck(buf, end, "/", default_str_spec);
1892
1893         for (depth = 0; parent->parent; depth++)
1894                 parent = parent->parent;
1895
1896         for ( ; depth >= 0; depth--) {
1897                 buf = string_nocheck(buf, end, "/", default_str_spec);
1898                 buf = string(buf, end, device_node_name_for_depth(np, depth),
1899                              default_str_spec);
1900         }
1901         return buf;
1902 }
1903
1904 static noinline_for_stack
1905 char *device_node_string(char *buf, char *end, struct device_node *dn,
1906                          struct printf_spec spec, const char *fmt)
1907 {
1908         char tbuf[sizeof("xxxx") + 1];
1909         const char *p;
1910         int ret;
1911         char *buf_start = buf;
1912         struct property *prop;
1913         bool has_mult, pass;
1914         static const struct printf_spec num_spec = {
1915                 .flags = SMALL,
1916                 .field_width = -1,
1917                 .precision = -1,
1918                 .base = 10,
1919         };
1920
1921         struct printf_spec str_spec = spec;
1922         str_spec.field_width = -1;
1923
1924         if (!IS_ENABLED(CONFIG_OF))
1925                 return error_string(buf, end, "(%pOF?)", spec);
1926
1927         if (check_pointer(&buf, end, dn, spec))
1928                 return buf;
1929
1930         /* simple case without anything any more format specifiers */
1931         fmt++;
1932         if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
1933                 fmt = "f";
1934
1935         for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
1936                 int precision;
1937                 if (pass) {
1938                         if (buf < end)
1939                                 *buf = ':';
1940                         buf++;
1941                 }
1942
1943                 switch (*fmt) {
1944                 case 'f':       /* full_name */
1945                         buf = device_node_gen_full_name(dn, buf, end);
1946                         break;
1947                 case 'n':       /* name */
1948                         p = kbasename(of_node_full_name(dn));
1949                         precision = str_spec.precision;
1950                         str_spec.precision = strchrnul(p, '@') - p;
1951                         buf = string(buf, end, p, str_spec);
1952                         str_spec.precision = precision;
1953                         break;
1954                 case 'p':       /* phandle */
1955                         buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
1956                         break;
1957                 case 'P':       /* path-spec */
1958                         p = kbasename(of_node_full_name(dn));
1959                         if (!p[1])
1960                                 p = "/";
1961                         buf = string(buf, end, p, str_spec);
1962                         break;
1963                 case 'F':       /* flags */
1964                         tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
1965                         tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
1966                         tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
1967                         tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
1968                         tbuf[4] = 0;
1969                         buf = string_nocheck(buf, end, tbuf, str_spec);
1970                         break;
1971                 case 'c':       /* major compatible string */
1972                         ret = of_property_read_string(dn, "compatible", &p);
1973                         if (!ret)
1974                                 buf = string(buf, end, p, str_spec);
1975                         break;
1976                 case 'C':       /* full compatible string */
1977                         has_mult = false;
1978                         of_property_for_each_string(dn, "compatible", prop, p) {
1979                                 if (has_mult)
1980                                         buf = string_nocheck(buf, end, ",", str_spec);
1981                                 buf = string_nocheck(buf, end, "\"", str_spec);
1982                                 buf = string(buf, end, p, str_spec);
1983                                 buf = string_nocheck(buf, end, "\"", str_spec);
1984
1985                                 has_mult = true;
1986                         }
1987                         break;
1988                 default:
1989                         break;
1990                 }
1991         }
1992
1993         return widen_string(buf, buf - buf_start, end, spec);
1994 }
1995
1996 static char *kobject_string(char *buf, char *end, void *ptr,
1997                             struct printf_spec spec, const char *fmt)
1998 {
1999         switch (fmt[1]) {
2000         case 'F':
2001                 return device_node_string(buf, end, ptr, spec, fmt + 1);
2002         }
2003
2004         return error_string(buf, end, "(%pO?)", spec);
2005 }
2006
2007 /*
2008  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
2009  * by an extra set of alphanumeric characters that are extended format
2010  * specifiers.
2011  *
2012  * Please update scripts/checkpatch.pl when adding/removing conversion
2013  * characters.  (Search for "check for vsprintf extension").
2014  *
2015  * Right now we handle:
2016  *
2017  * - 'S' For symbolic direct pointers (or function descriptors) with offset
2018  * - 's' For symbolic direct pointers (or function descriptors) without offset
2019  * - 'F' Same as 'S'
2020  * - 'f' Same as 's'
2021  * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
2022  * - 'B' For backtraced symbolic direct pointers with offset
2023  * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
2024  * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
2025  * - 'b[l]' For a bitmap, the number of bits is determined by the field
2026  *       width which must be explicitly specified either as part of the
2027  *       format string '%32b[l]' or through '%*b[l]', [l] selects
2028  *       range-list format instead of hex format
2029  * - 'M' For a 6-byte MAC address, it prints the address in the
2030  *       usual colon-separated hex notation
2031  * - 'm' For a 6-byte MAC address, it prints the hex address without colons
2032  * - 'MF' For a 6-byte MAC FDDI address, it prints the address
2033  *       with a dash-separated hex notation
2034  * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
2035  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
2036  *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
2037  *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
2038  *       [S][pfs]
2039  *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2040  *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2041  * - 'i' [46] for 'raw' IPv4/IPv6 addresses
2042  *       IPv6 omits the colons (01020304...0f)
2043  *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
2044  *       [S][pfs]
2045  *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2046  *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2047  * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
2048  * - 'I[6S]c' for IPv6 addresses printed as specified by
2049  *       http://tools.ietf.org/html/rfc5952
2050  * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
2051  *                of the following flags (see string_escape_mem() for the
2052  *                details):
2053  *                  a - ESCAPE_ANY
2054  *                  c - ESCAPE_SPECIAL
2055  *                  h - ESCAPE_HEX
2056  *                  n - ESCAPE_NULL
2057  *                  o - ESCAPE_OCTAL
2058  *                  p - ESCAPE_NP
2059  *                  s - ESCAPE_SPACE
2060  *                By default ESCAPE_ANY_NP is used.
2061  * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
2062  *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
2063  *       Options for %pU are:
2064  *         b big endian lower case hex (default)
2065  *         B big endian UPPER case hex
2066  *         l little endian lower case hex
2067  *         L little endian UPPER case hex
2068  *           big endian output byte order is:
2069  *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
2070  *           little endian output byte order is:
2071  *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
2072  * - 'V' For a struct va_format which contains a format string * and va_list *,
2073  *       call vsnprintf(->format, *->va_list).
2074  *       Implements a "recursive vsnprintf".
2075  *       Do not use this feature without some mechanism to verify the
2076  *       correctness of the format string and va_list arguments.
2077  * - 'K' For a kernel pointer that should be hidden from unprivileged users
2078  * - 'NF' For a netdev_features_t
2079  * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
2080  *            a certain separator (' ' by default):
2081  *              C colon
2082  *              D dash
2083  *              N no separator
2084  *            The maximum supported length is 64 bytes of the input. Consider
2085  *            to use print_hex_dump() for the larger input.
2086  * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
2087  *           (default assumed to be phys_addr_t, passed by reference)
2088  * - 'd[234]' For a dentry name (optionally 2-4 last components)
2089  * - 'D[234]' Same as 'd' but for a struct file
2090  * - 'g' For block_device name (gendisk + partition number)
2091  * - 't[R][dt][r]' For time and date as represented:
2092  *      R    struct rtc_time
2093  * - 'C' For a clock, it prints the name (Common Clock Framework) or address
2094  *       (legacy clock framework) of the clock
2095  * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
2096  *        (legacy clock framework) of the clock
2097  * - 'G' For flags to be printed as a collection of symbolic strings that would
2098  *       construct the specific value. Supported flags given by option:
2099  *       p page flags (see struct page) given as pointer to unsigned long
2100  *       g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
2101  *       v vma flags (VM_*) given as pointer to unsigned long
2102  * - 'OF[fnpPcCF]'  For a device tree object
2103  *                  Without any optional arguments prints the full_name
2104  *                  f device node full_name
2105  *                  n device node name
2106  *                  p device node phandle
2107  *                  P device node path spec (name + @unit)
2108  *                  F device node flags
2109  *                  c major compatible string
2110  *                  C full compatible string
2111  * - 'x' For printing the address. Equivalent to "%lx".
2112  *
2113  * ** When making changes please also update:
2114  *      Documentation/core-api/printk-formats.rst
2115  *
2116  * Note: The default behaviour (unadorned %p) is to hash the address,
2117  * rendering it useful as a unique identifier.
2118  */
2119 static noinline_for_stack
2120 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
2121               struct printf_spec spec)
2122 {
2123         switch (*fmt) {
2124         case 'F':
2125         case 'f':
2126         case 'S':
2127         case 's':
2128                 ptr = dereference_symbol_descriptor(ptr);
2129                 /* Fallthrough */
2130         case 'B':
2131                 return symbol_string(buf, end, ptr, spec, fmt);
2132         case 'R':
2133         case 'r':
2134                 return resource_string(buf, end, ptr, spec, fmt);
2135         case 'h':
2136                 return hex_string(buf, end, ptr, spec, fmt);
2137         case 'b':
2138                 switch (fmt[1]) {
2139                 case 'l':
2140                         return bitmap_list_string(buf, end, ptr, spec, fmt);
2141                 default:
2142                         return bitmap_string(buf, end, ptr, spec, fmt);
2143                 }
2144         case 'M':                       /* Colon separated: 00:01:02:03:04:05 */
2145         case 'm':                       /* Contiguous: 000102030405 */
2146                                         /* [mM]F (FDDI) */
2147                                         /* [mM]R (Reverse order; Bluetooth) */
2148                 return mac_address_string(buf, end, ptr, spec, fmt);
2149         case 'I':                       /* Formatted IP supported
2150                                          * 4:   1.2.3.4
2151                                          * 6:   0001:0203:...:0708
2152                                          * 6c:  1::708 or 1::1.2.3.4
2153                                          */
2154         case 'i':                       /* Contiguous:
2155                                          * 4:   001.002.003.004
2156                                          * 6:   000102...0f
2157                                          */
2158                 return ip_addr_string(buf, end, ptr, spec, fmt);
2159         case 'E':
2160                 return escaped_string(buf, end, ptr, spec, fmt);
2161         case 'U':
2162                 return uuid_string(buf, end, ptr, spec, fmt);
2163         case 'V':
2164                 return va_format(buf, end, ptr, spec, fmt);
2165         case 'K':
2166                 return restricted_pointer(buf, end, ptr, spec);
2167         case 'N':
2168                 return netdev_bits(buf, end, ptr, spec, fmt);
2169         case 'a':
2170                 return address_val(buf, end, ptr, spec, fmt);
2171         case 'd':
2172                 return dentry_name(buf, end, ptr, spec, fmt);
2173         case 't':
2174                 return time_and_date(buf, end, ptr, spec, fmt);
2175         case 'C':
2176                 return clock(buf, end, ptr, spec, fmt);
2177         case 'D':
2178                 return file_dentry_name(buf, end, ptr, spec, fmt);
2179 #ifdef CONFIG_BLOCK
2180         case 'g':
2181                 return bdev_name(buf, end, ptr, spec, fmt);
2182 #endif
2183
2184         case 'G':
2185                 return flags_string(buf, end, ptr, spec, fmt);
2186         case 'O':
2187                 return kobject_string(buf, end, ptr, spec, fmt);
2188         case 'x':
2189                 return pointer_string(buf, end, ptr, spec);
2190         }
2191
2192         /* default is to _not_ leak addresses, hash before printing */
2193         return ptr_to_id(buf, end, ptr, spec);
2194 }
2195
2196 /*
2197  * Helper function to decode printf style format.
2198  * Each call decode a token from the format and return the
2199  * number of characters read (or likely the delta where it wants
2200  * to go on the next call).
2201  * The decoded token is returned through the parameters
2202  *
2203  * 'h', 'l', or 'L' for integer fields
2204  * 'z' support added 23/7/1999 S.H.
2205  * 'z' changed to 'Z' --davidm 1/25/99
2206  * 'Z' changed to 'z' --adobriyan 2017-01-25
2207  * 't' added for ptrdiff_t
2208  *
2209  * @fmt: the format string
2210  * @type of the token returned
2211  * @flags: various flags such as +, -, # tokens..
2212  * @field_width: overwritten width
2213  * @base: base of the number (octal, hex, ...)
2214  * @precision: precision of a number
2215  * @qualifier: qualifier of a number (long, size_t, ...)
2216  */
2217 static noinline_for_stack
2218 int format_decode(const char *fmt, struct printf_spec *spec)
2219 {
2220         const char *start = fmt;
2221         char qualifier;
2222
2223         /* we finished early by reading the field width */
2224         if (spec->type == FORMAT_TYPE_WIDTH) {
2225                 if (spec->field_width < 0) {
2226                         spec->field_width = -spec->field_width;
2227                         spec->flags |= LEFT;
2228                 }
2229                 spec->type = FORMAT_TYPE_NONE;
2230                 goto precision;
2231         }
2232
2233         /* we finished early by reading the precision */
2234         if (spec->type == FORMAT_TYPE_PRECISION) {
2235                 if (spec->precision < 0)
2236                         spec->precision = 0;
2237
2238                 spec->type = FORMAT_TYPE_NONE;
2239                 goto qualifier;
2240         }
2241
2242         /* By default */
2243         spec->type = FORMAT_TYPE_NONE;
2244
2245         for (; *fmt ; ++fmt) {
2246                 if (*fmt == '%')
2247                         break;
2248         }
2249
2250         /* Return the current non-format string */
2251         if (fmt != start || !*fmt)
2252                 return fmt - start;
2253
2254         /* Process flags */
2255         spec->flags = 0;
2256
2257         while (1) { /* this also skips first '%' */
2258                 bool found = true;
2259
2260                 ++fmt;
2261
2262                 switch (*fmt) {
2263                 case '-': spec->flags |= LEFT;    break;
2264                 case '+': spec->flags |= PLUS;    break;
2265                 case ' ': spec->flags |= SPACE;   break;
2266                 case '#': spec->flags |= SPECIAL; break;
2267                 case '0': spec->flags |= ZEROPAD; break;
2268                 default:  found = false;
2269                 }
2270
2271                 if (!found)
2272                         break;
2273         }
2274
2275         /* get field width */
2276         spec->field_width = -1;
2277
2278         if (isdigit(*fmt))
2279                 spec->field_width = skip_atoi(&fmt);
2280         else if (*fmt == '*') {
2281                 /* it's the next argument */
2282                 spec->type = FORMAT_TYPE_WIDTH;
2283                 return ++fmt - start;
2284         }
2285
2286 precision:
2287         /* get the precision */
2288         spec->precision = -1;
2289         if (*fmt == '.') {
2290                 ++fmt;
2291                 if (isdigit(*fmt)) {
2292                         spec->precision = skip_atoi(&fmt);
2293                         if (spec->precision < 0)
2294                                 spec->precision = 0;
2295                 } else if (*fmt == '*') {
2296                         /* it's the next argument */
2297                         spec->type = FORMAT_TYPE_PRECISION;
2298                         return ++fmt - start;
2299                 }
2300         }
2301
2302 qualifier:
2303         /* get the conversion qualifier */
2304         qualifier = 0;
2305         if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2306             *fmt == 'z' || *fmt == 't') {
2307                 qualifier = *fmt++;
2308                 if (unlikely(qualifier == *fmt)) {
2309                         if (qualifier == 'l') {
2310                                 qualifier = 'L';
2311                                 ++fmt;
2312                         } else if (qualifier == 'h') {
2313                                 qualifier = 'H';
2314                                 ++fmt;
2315                         }
2316                 }
2317         }
2318
2319         /* default base */
2320         spec->base = 10;
2321         switch (*fmt) {
2322         case 'c':
2323                 spec->type = FORMAT_TYPE_CHAR;
2324                 return ++fmt - start;
2325
2326         case 's':
2327                 spec->type = FORMAT_TYPE_STR;
2328                 return ++fmt - start;
2329
2330         case 'p':
2331                 spec->type = FORMAT_TYPE_PTR;
2332                 return ++fmt - start;
2333
2334         case '%':
2335                 spec->type = FORMAT_TYPE_PERCENT_CHAR;
2336                 return ++fmt - start;
2337
2338         /* integer number formats - set up the flags and "break" */
2339         case 'o':
2340                 spec->base = 8;
2341                 break;
2342
2343         case 'x':
2344                 spec->flags |= SMALL;
2345                 /* fall through */
2346
2347         case 'X':
2348                 spec->base = 16;
2349                 break;
2350
2351         case 'd':
2352         case 'i':
2353                 spec->flags |= SIGN;
2354         case 'u':
2355                 break;
2356
2357         case 'n':
2358                 /*
2359                  * Since %n poses a greater security risk than
2360                  * utility, treat it as any other invalid or
2361                  * unsupported format specifier.
2362                  */
2363                 /* Fall-through */
2364
2365         default:
2366                 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2367                 spec->type = FORMAT_TYPE_INVALID;
2368                 return fmt - start;
2369         }
2370
2371         if (qualifier == 'L')
2372                 spec->type = FORMAT_TYPE_LONG_LONG;
2373         else if (qualifier == 'l') {
2374                 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2375                 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2376         } else if (qualifier == 'z') {
2377                 spec->type = FORMAT_TYPE_SIZE_T;
2378         } else if (qualifier == 't') {
2379                 spec->type = FORMAT_TYPE_PTRDIFF;
2380         } else if (qualifier == 'H') {
2381                 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2382                 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2383         } else if (qualifier == 'h') {
2384                 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2385                 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2386         } else {
2387                 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2388                 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2389         }
2390
2391         return ++fmt - start;
2392 }
2393
2394 static void
2395 set_field_width(struct printf_spec *spec, int width)
2396 {
2397         spec->field_width = width;
2398         if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2399                 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2400         }
2401 }
2402
2403 static void
2404 set_precision(struct printf_spec *spec, int prec)
2405 {
2406         spec->precision = prec;
2407         if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2408                 spec->precision = clamp(prec, 0, PRECISION_MAX);
2409         }
2410 }
2411
2412 /**
2413  * vsnprintf - Format a string and place it in a buffer
2414  * @buf: The buffer to place the result into
2415  * @size: The size of the buffer, including the trailing null space
2416  * @fmt: The format string to use
2417  * @args: Arguments for the format string
2418  *
2419  * This function generally follows C99 vsnprintf, but has some
2420  * extensions and a few limitations:
2421  *
2422  *  - ``%n`` is unsupported
2423  *  - ``%p*`` is handled by pointer()
2424  *
2425  * See pointer() or Documentation/core-api/printk-formats.rst for more
2426  * extensive description.
2427  *
2428  * **Please update the documentation in both places when making changes**
2429  *
2430  * The return value is the number of characters which would
2431  * be generated for the given input, excluding the trailing
2432  * '\0', as per ISO C99. If you want to have the exact
2433  * number of characters written into @buf as return value
2434  * (not including the trailing '\0'), use vscnprintf(). If the
2435  * return is greater than or equal to @size, the resulting
2436  * string is truncated.
2437  *
2438  * If you're not already dealing with a va_list consider using snprintf().
2439  */
2440 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2441 {
2442         unsigned long long num;
2443         char *str, *end;
2444         struct printf_spec spec = {0};
2445
2446         /* Reject out-of-range values early.  Large positive sizes are
2447            used for unknown buffer sizes. */
2448         if (WARN_ON_ONCE(size > INT_MAX))
2449                 return 0;
2450
2451         str = buf;
2452         end = buf + size;
2453
2454         /* Make sure end is always >= buf */
2455         if (end < buf) {
2456                 end = ((void *)-1);
2457                 size = end - buf;
2458         }
2459
2460         while (*fmt) {
2461                 const char *old_fmt = fmt;
2462                 int read = format_decode(fmt, &spec);
2463
2464                 fmt += read;
2465
2466                 switch (spec.type) {
2467                 case FORMAT_TYPE_NONE: {
2468                         int copy = read;
2469                         if (str < end) {
2470                                 if (copy > end - str)
2471                                         copy = end - str;
2472                                 memcpy(str, old_fmt, copy);
2473                         }
2474                         str += read;
2475                         break;
2476                 }
2477
2478                 case FORMAT_TYPE_WIDTH:
2479                         set_field_width(&spec, va_arg(args, int));
2480                         break;
2481
2482                 case FORMAT_TYPE_PRECISION:
2483                         set_precision(&spec, va_arg(args, int));
2484                         break;
2485
2486                 case FORMAT_TYPE_CHAR: {
2487                         char c;
2488
2489                         if (!(spec.flags & LEFT)) {
2490                                 while (--spec.field_width > 0) {
2491                                         if (str < end)
2492                                                 *str = ' ';
2493                                         ++str;
2494
2495                                 }
2496                         }
2497                         c = (unsigned char) va_arg(args, int);
2498                         if (str < end)
2499                                 *str = c;
2500                         ++str;
2501                         while (--spec.field_width > 0) {
2502                                 if (str < end)
2503                                         *str = ' ';
2504                                 ++str;
2505                         }
2506                         break;
2507                 }
2508
2509                 case FORMAT_TYPE_STR:
2510                         str = string(str, end, va_arg(args, char *), spec);
2511                         break;
2512
2513                 case FORMAT_TYPE_PTR:
2514                         str = pointer(fmt, str, end, va_arg(args, void *),
2515                                       spec);
2516                         while (isalnum(*fmt))
2517                                 fmt++;
2518                         break;
2519
2520                 case FORMAT_TYPE_PERCENT_CHAR:
2521                         if (str < end)
2522                                 *str = '%';
2523                         ++str;
2524                         break;
2525
2526                 case FORMAT_TYPE_INVALID:
2527                         /*
2528                          * Presumably the arguments passed gcc's type
2529                          * checking, but there is no safe or sane way
2530                          * for us to continue parsing the format and
2531                          * fetching from the va_list; the remaining
2532                          * specifiers and arguments would be out of
2533                          * sync.
2534                          */
2535                         goto out;
2536
2537                 default:
2538                         switch (spec.type) {
2539                         case FORMAT_TYPE_LONG_LONG:
2540                                 num = va_arg(args, long long);
2541                                 break;
2542                         case FORMAT_TYPE_ULONG:
2543                                 num = va_arg(args, unsigned long);
2544                                 break;
2545                         case FORMAT_TYPE_LONG:
2546                                 num = va_arg(args, long);
2547                                 break;
2548                         case FORMAT_TYPE_SIZE_T:
2549                                 if (spec.flags & SIGN)
2550                                         num = va_arg(args, ssize_t);
2551                                 else
2552                                         num = va_arg(args, size_t);
2553                                 break;
2554                         case FORMAT_TYPE_PTRDIFF:
2555                                 num = va_arg(args, ptrdiff_t);
2556                                 break;
2557                         case FORMAT_TYPE_UBYTE:
2558                                 num = (unsigned char) va_arg(args, int);
2559                                 break;
2560                         case FORMAT_TYPE_BYTE:
2561                                 num = (signed char) va_arg(args, int);
2562                                 break;
2563                         case FORMAT_TYPE_USHORT:
2564                                 num = (unsigned short) va_arg(args, int);
2565                                 break;
2566                         case FORMAT_TYPE_SHORT:
2567                                 num = (short) va_arg(args, int);
2568                                 break;
2569                         case FORMAT_TYPE_INT:
2570                                 num = (int) va_arg(args, int);
2571                                 break;
2572                         default:
2573                                 num = va_arg(args, unsigned int);
2574                         }
2575
2576                         str = number(str, end, num, spec);
2577                 }
2578         }
2579
2580 out:
2581         if (size > 0) {
2582                 if (str < end)
2583                         *str = '\0';
2584                 else
2585                         end[-1] = '\0';
2586         }
2587
2588         /* the trailing null byte doesn't count towards the total */
2589         return str-buf;
2590
2591 }
2592 EXPORT_SYMBOL(vsnprintf);
2593
2594 /**
2595  * vscnprintf - Format a string and place it in a buffer
2596  * @buf: The buffer to place the result into
2597  * @size: The size of the buffer, including the trailing null space
2598  * @fmt: The format string to use
2599  * @args: Arguments for the format string
2600  *
2601  * The return value is the number of characters which have been written into
2602  * the @buf not including the trailing '\0'. If @size is == 0 the function
2603  * returns 0.
2604  *
2605  * If you're not already dealing with a va_list consider using scnprintf().
2606  *
2607  * See the vsnprintf() documentation for format string extensions over C99.
2608  */
2609 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2610 {
2611         int i;
2612
2613         i = vsnprintf(buf, size, fmt, args);
2614
2615         if (likely(i < size))
2616                 return i;
2617         if (size != 0)
2618                 return size - 1;
2619         return 0;
2620 }
2621 EXPORT_SYMBOL(vscnprintf);
2622
2623 /**
2624  * snprintf - Format a string and place it in a buffer
2625  * @buf: The buffer to place the result into
2626  * @size: The size of the buffer, including the trailing null space
2627  * @fmt: The format string to use
2628  * @...: Arguments for the format string
2629  *
2630  * The return value is the number of characters which would be
2631  * generated for the given input, excluding the trailing null,
2632  * as per ISO C99.  If the return is greater than or equal to
2633  * @size, the resulting string is truncated.
2634  *
2635  * See the vsnprintf() documentation for format string extensions over C99.
2636  */
2637 int snprintf(char *buf, size_t size, const char *fmt, ...)
2638 {
2639         va_list args;
2640         int i;
2641
2642         va_start(args, fmt);
2643         i = vsnprintf(buf, size, fmt, args);
2644         va_end(args);
2645
2646         return i;
2647 }
2648 EXPORT_SYMBOL(snprintf);
2649
2650 /**
2651  * scnprintf - Format a string and place it in a buffer
2652  * @buf: The buffer to place the result into
2653  * @size: The size of the buffer, including the trailing null space
2654  * @fmt: The format string to use
2655  * @...: Arguments for the format string
2656  *
2657  * The return value is the number of characters written into @buf not including
2658  * the trailing '\0'. If @size is == 0 the function returns 0.
2659  */
2660
2661 int scnprintf(char *buf, size_t size, const char *fmt, ...)
2662 {
2663         va_list args;
2664         int i;
2665
2666         va_start(args, fmt);
2667         i = vscnprintf(buf, size, fmt, args);
2668         va_end(args);
2669
2670         return i;
2671 }
2672 EXPORT_SYMBOL(scnprintf);
2673
2674 /**
2675  * vsprintf - Format a string and place it in a buffer
2676  * @buf: The buffer to place the result into
2677  * @fmt: The format string to use
2678  * @args: Arguments for the format string
2679  *
2680  * The function returns the number of characters written
2681  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2682  * buffer overflows.
2683  *
2684  * If you're not already dealing with a va_list consider using sprintf().
2685  *
2686  * See the vsnprintf() documentation for format string extensions over C99.
2687  */
2688 int vsprintf(char *buf, const char *fmt, va_list args)
2689 {
2690         return vsnprintf(buf, INT_MAX, fmt, args);
2691 }
2692 EXPORT_SYMBOL(vsprintf);
2693
2694 /**
2695  * sprintf - Format a string and place it in a buffer
2696  * @buf: The buffer to place the result into
2697  * @fmt: The format string to use
2698  * @...: Arguments for the format string
2699  *
2700  * The function returns the number of characters written
2701  * into @buf. Use snprintf() or scnprintf() in order to avoid
2702  * buffer overflows.
2703  *
2704  * See the vsnprintf() documentation for format string extensions over C99.
2705  */
2706 int sprintf(char *buf, const char *fmt, ...)
2707 {
2708         va_list args;
2709         int i;
2710
2711         va_start(args, fmt);
2712         i = vsnprintf(buf, INT_MAX, fmt, args);
2713         va_end(args);
2714
2715         return i;
2716 }
2717 EXPORT_SYMBOL(sprintf);
2718
2719 #ifdef CONFIG_BINARY_PRINTF
2720 /*
2721  * bprintf service:
2722  * vbin_printf() - VA arguments to binary data
2723  * bstr_printf() - Binary data to text string
2724  */
2725
2726 /**
2727  * vbin_printf - Parse a format string and place args' binary value in a buffer
2728  * @bin_buf: The buffer to place args' binary value
2729  * @size: The size of the buffer(by words(32bits), not characters)
2730  * @fmt: The format string to use
2731  * @args: Arguments for the format string
2732  *
2733  * The format follows C99 vsnprintf, except %n is ignored, and its argument
2734  * is skipped.
2735  *
2736  * The return value is the number of words(32bits) which would be generated for
2737  * the given input.
2738  *
2739  * NOTE:
2740  * If the return value is greater than @size, the resulting bin_buf is NOT
2741  * valid for bstr_printf().
2742  */
2743 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2744 {
2745         struct printf_spec spec = {0};
2746         char *str, *end;
2747         int width;
2748
2749         str = (char *)bin_buf;
2750         end = (char *)(bin_buf + size);
2751
2752 #define save_arg(type)                                                  \
2753 ({                                                                      \
2754         unsigned long long value;                                       \
2755         if (sizeof(type) == 8) {                                        \
2756                 unsigned long long val8;                                \
2757                 str = PTR_ALIGN(str, sizeof(u32));                      \
2758                 val8 = va_arg(args, unsigned long long);                \
2759                 if (str + sizeof(type) <= end) {                        \
2760                         *(u32 *)str = *(u32 *)&val8;                    \
2761                         *(u32 *)(str + 4) = *((u32 *)&val8 + 1);        \
2762                 }                                                       \
2763                 value = val8;                                           \
2764         } else {                                                        \
2765                 unsigned int val4;                                      \
2766                 str = PTR_ALIGN(str, sizeof(type));                     \
2767                 val4 = va_arg(args, int);                               \
2768                 if (str + sizeof(type) <= end)                          \
2769                         *(typeof(type) *)str = (type)(long)val4;        \
2770                 value = (unsigned long long)val4;                       \
2771         }                                                               \
2772         str += sizeof(type);                                            \
2773         value;                                                          \
2774 })
2775
2776         while (*fmt) {
2777                 int read = format_decode(fmt, &spec);
2778
2779                 fmt += read;
2780
2781                 switch (spec.type) {
2782                 case FORMAT_TYPE_NONE:
2783                 case FORMAT_TYPE_PERCENT_CHAR:
2784                         break;
2785                 case FORMAT_TYPE_INVALID:
2786                         goto out;
2787
2788                 case FORMAT_TYPE_WIDTH:
2789                 case FORMAT_TYPE_PRECISION:
2790                         width = (int)save_arg(int);
2791                         /* Pointers may require the width */
2792                         if (*fmt == 'p')
2793                                 set_field_width(&spec, width);
2794                         break;
2795
2796                 case FORMAT_TYPE_CHAR:
2797                         save_arg(char);
2798                         break;
2799
2800                 case FORMAT_TYPE_STR: {
2801                         const char *save_str = va_arg(args, char *);
2802                         const char *err_msg;
2803                         size_t len;
2804
2805                         err_msg = check_pointer_msg(save_str);
2806                         if (err_msg)
2807                                 save_str = err_msg;
2808
2809                         len = strlen(save_str) + 1;
2810                         if (str + len < end)
2811                                 memcpy(str, save_str, len);
2812                         str += len;
2813                         break;
2814                 }
2815
2816                 case FORMAT_TYPE_PTR:
2817                         /* Dereferenced pointers must be done now */
2818                         switch (*fmt) {
2819                         /* Dereference of functions is still OK */
2820                         case 'S':
2821                         case 's':
2822                         case 'F':
2823                         case 'f':
2824                         case 'x':
2825                         case 'K':
2826                                 save_arg(void *);
2827                                 break;
2828                         default:
2829                                 if (!isalnum(*fmt)) {
2830                                         save_arg(void *);
2831                                         break;
2832                                 }
2833                                 str = pointer(fmt, str, end, va_arg(args, void *),
2834                                               spec);
2835                                 if (str + 1 < end)
2836                                         *str++ = '\0';
2837                                 else
2838                                         end[-1] = '\0'; /* Must be nul terminated */
2839                         }
2840                         /* skip all alphanumeric pointer suffixes */
2841                         while (isalnum(*fmt))
2842                                 fmt++;
2843                         break;
2844
2845                 default:
2846                         switch (spec.type) {
2847
2848                         case FORMAT_TYPE_LONG_LONG:
2849                                 save_arg(long long);
2850                                 break;
2851                         case FORMAT_TYPE_ULONG:
2852                         case FORMAT_TYPE_LONG:
2853                                 save_arg(unsigned long);
2854                                 break;
2855                         case FORMAT_TYPE_SIZE_T:
2856                                 save_arg(size_t);
2857                                 break;
2858                         case FORMAT_TYPE_PTRDIFF:
2859                                 save_arg(ptrdiff_t);
2860                                 break;
2861                         case FORMAT_TYPE_UBYTE:
2862                         case FORMAT_TYPE_BYTE:
2863                                 save_arg(char);
2864                                 break;
2865                         case FORMAT_TYPE_USHORT:
2866                         case FORMAT_TYPE_SHORT:
2867                                 save_arg(short);
2868                                 break;
2869                         default:
2870                                 save_arg(int);
2871                         }
2872                 }
2873         }
2874
2875 out:
2876         return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2877 #undef save_arg
2878 }
2879 EXPORT_SYMBOL_GPL(vbin_printf);
2880
2881 /**
2882  * bstr_printf - Format a string from binary arguments 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  * @bin_buf: Binary arguments for the format string
2887  *
2888  * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2889  * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2890  * a binary buffer that generated by vbin_printf.
2891  *
2892  * The format follows C99 vsnprintf, but has some extensions:
2893  *  see vsnprintf comment for details.
2894  *
2895  * The return value is the number of characters which would
2896  * be generated for the given input, excluding the trailing
2897  * '\0', as per ISO C99. If you want to have the exact
2898  * number of characters written into @buf as return value
2899  * (not including the trailing '\0'), use vscnprintf(). If the
2900  * return is greater than or equal to @size, the resulting
2901  * string is truncated.
2902  */
2903 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2904 {
2905         struct printf_spec spec = {0};
2906         char *str, *end;
2907         const char *args = (const char *)bin_buf;
2908
2909         if (WARN_ON_ONCE(size > INT_MAX))
2910                 return 0;
2911
2912         str = buf;
2913         end = buf + size;
2914
2915 #define get_arg(type)                                                   \
2916 ({                                                                      \
2917         typeof(type) value;                                             \
2918         if (sizeof(type) == 8) {                                        \
2919                 args = PTR_ALIGN(args, sizeof(u32));                    \
2920                 *(u32 *)&value = *(u32 *)args;                          \
2921                 *((u32 *)&value + 1) = *(u32 *)(args + 4);              \
2922         } else {                                                        \
2923                 args = PTR_ALIGN(args, sizeof(type));                   \
2924                 value = *(typeof(type) *)args;                          \
2925         }                                                               \
2926         args += sizeof(type);                                           \
2927         value;                                                          \
2928 })
2929
2930         /* Make sure end is always >= buf */
2931         if (end < buf) {
2932                 end = ((void *)-1);
2933                 size = end - buf;
2934         }
2935
2936         while (*fmt) {
2937                 const char *old_fmt = fmt;
2938                 int read = format_decode(fmt, &spec);
2939
2940                 fmt += read;
2941
2942                 switch (spec.type) {
2943                 case FORMAT_TYPE_NONE: {
2944                         int copy = read;
2945                         if (str < end) {
2946                                 if (copy > end - str)
2947                                         copy = end - str;
2948                                 memcpy(str, old_fmt, copy);
2949                         }
2950                         str += read;
2951                         break;
2952                 }
2953
2954                 case FORMAT_TYPE_WIDTH:
2955                         set_field_width(&spec, get_arg(int));
2956                         break;
2957
2958                 case FORMAT_TYPE_PRECISION:
2959                         set_precision(&spec, get_arg(int));
2960                         break;
2961
2962                 case FORMAT_TYPE_CHAR: {
2963                         char c;
2964
2965                         if (!(spec.flags & LEFT)) {
2966                                 while (--spec.field_width > 0) {
2967                                         if (str < end)
2968                                                 *str = ' ';
2969                                         ++str;
2970                                 }
2971                         }
2972                         c = (unsigned char) get_arg(char);
2973                         if (str < end)
2974                                 *str = c;
2975                         ++str;
2976                         while (--spec.field_width > 0) {
2977                                 if (str < end)
2978                                         *str = ' ';
2979                                 ++str;
2980                         }
2981                         break;
2982                 }
2983
2984                 case FORMAT_TYPE_STR: {
2985                         const char *str_arg = args;
2986                         args += strlen(str_arg) + 1;
2987                         str = string(str, end, (char *)str_arg, spec);
2988                         break;
2989                 }
2990
2991                 case FORMAT_TYPE_PTR: {
2992                         bool process = false;
2993                         int copy, len;
2994                         /* Non function dereferences were already done */
2995                         switch (*fmt) {
2996                         case 'S':
2997                         case 's':
2998                         case 'F':
2999                         case 'f':
3000                         case 'x':
3001                         case 'K':
3002                                 process = true;
3003                                 break;
3004                         default:
3005                                 if (!isalnum(*fmt)) {
3006                                         process = true;
3007                                         break;
3008                                 }
3009                                 /* Pointer dereference was already processed */
3010                                 if (str < end) {
3011                                         len = copy = strlen(args);
3012                                         if (copy > end - str)
3013                                                 copy = end - str;
3014                                         memcpy(str, args, copy);
3015                                         str += len;
3016                                         args += len + 1;
3017                                 }
3018                         }
3019                         if (process)
3020                                 str = pointer(fmt, str, end, get_arg(void *), spec);
3021
3022                         while (isalnum(*fmt))
3023                                 fmt++;
3024                         break;
3025                 }
3026
3027                 case FORMAT_TYPE_PERCENT_CHAR:
3028                         if (str < end)
3029                                 *str = '%';
3030                         ++str;
3031                         break;
3032
3033                 case FORMAT_TYPE_INVALID:
3034                         goto out;
3035
3036                 default: {
3037                         unsigned long long num;
3038
3039                         switch (spec.type) {
3040
3041                         case FORMAT_TYPE_LONG_LONG:
3042                                 num = get_arg(long long);
3043                                 break;
3044                         case FORMAT_TYPE_ULONG:
3045                         case FORMAT_TYPE_LONG:
3046                                 num = get_arg(unsigned long);
3047                                 break;
3048                         case FORMAT_TYPE_SIZE_T:
3049                                 num = get_arg(size_t);
3050                                 break;
3051                         case FORMAT_TYPE_PTRDIFF:
3052                                 num = get_arg(ptrdiff_t);
3053                                 break;
3054                         case FORMAT_TYPE_UBYTE:
3055                                 num = get_arg(unsigned char);
3056                                 break;
3057                         case FORMAT_TYPE_BYTE:
3058                                 num = get_arg(signed char);
3059                                 break;
3060                         case FORMAT_TYPE_USHORT:
3061                                 num = get_arg(unsigned short);
3062                                 break;
3063                         case FORMAT_TYPE_SHORT:
3064                                 num = get_arg(short);
3065                                 break;
3066                         case FORMAT_TYPE_UINT:
3067                                 num = get_arg(unsigned int);
3068                                 break;
3069                         default:
3070                                 num = get_arg(int);
3071                         }
3072
3073                         str = number(str, end, num, spec);
3074                 } /* default: */
3075                 } /* switch(spec.type) */
3076         } /* while(*fmt) */
3077
3078 out:
3079         if (size > 0) {
3080                 if (str < end)
3081                         *str = '\0';
3082                 else
3083                         end[-1] = '\0';
3084         }
3085
3086 #undef get_arg
3087
3088         /* the trailing null byte doesn't count towards the total */
3089         return str - buf;
3090 }
3091 EXPORT_SYMBOL_GPL(bstr_printf);
3092
3093 /**
3094  * bprintf - Parse a format string and place args' binary value in a buffer
3095  * @bin_buf: The buffer to place args' binary value
3096  * @size: The size of the buffer(by words(32bits), not characters)
3097  * @fmt: The format string to use
3098  * @...: Arguments for the format string
3099  *
3100  * The function returns the number of words(u32) written
3101  * into @bin_buf.
3102  */
3103 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
3104 {
3105         va_list args;
3106         int ret;
3107
3108         va_start(args, fmt);
3109         ret = vbin_printf(bin_buf, size, fmt, args);
3110         va_end(args);
3111
3112         return ret;
3113 }
3114 EXPORT_SYMBOL_GPL(bprintf);
3115
3116 #endif /* CONFIG_BINARY_PRINTF */
3117
3118 /**
3119  * vsscanf - Unformat a buffer into a list of arguments
3120  * @buf:        input buffer
3121  * @fmt:        format of buffer
3122  * @args:       arguments
3123  */
3124 int vsscanf(const char *buf, const char *fmt, va_list args)
3125 {
3126         const char *str = buf;
3127         char *next;
3128         char digit;
3129         int num = 0;
3130         u8 qualifier;
3131         unsigned int base;
3132         union {
3133                 long long s;
3134                 unsigned long long u;
3135         } val;
3136         s16 field_width;
3137         bool is_sign;
3138
3139         while (*fmt) {
3140                 /* skip any white space in format */
3141                 /* white space in format matchs any amount of
3142                  * white space, including none, in the input.
3143                  */
3144                 if (isspace(*fmt)) {
3145                         fmt = skip_spaces(++fmt);
3146                         str = skip_spaces(str);
3147                 }
3148
3149                 /* anything that is not a conversion must match exactly */
3150                 if (*fmt != '%' && *fmt) {
3151                         if (*fmt++ != *str++)
3152                                 break;
3153                         continue;
3154                 }
3155
3156                 if (!*fmt)
3157                         break;
3158                 ++fmt;
3159
3160                 /* skip this conversion.
3161                  * advance both strings to next white space
3162                  */
3163                 if (*fmt == '*') {
3164                         if (!*str)
3165                                 break;
3166                         while (!isspace(*fmt) && *fmt != '%' && *fmt) {
3167                                 /* '%*[' not yet supported, invalid format */
3168                                 if (*fmt == '[')
3169                                         return num;
3170                                 fmt++;
3171                         }
3172                         while (!isspace(*str) && *str)
3173                                 str++;
3174                         continue;
3175                 }
3176
3177                 /* get field width */
3178                 field_width = -1;
3179                 if (isdigit(*fmt)) {
3180                         field_width = skip_atoi(&fmt);
3181                         if (field_width <= 0)
3182                                 break;
3183                 }
3184
3185                 /* get conversion qualifier */
3186                 qualifier = -1;
3187                 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
3188                     *fmt == 'z') {
3189                         qualifier = *fmt++;
3190                         if (unlikely(qualifier == *fmt)) {
3191                                 if (qualifier == 'h') {
3192                                         qualifier = 'H';
3193                                         fmt++;
3194                                 } else if (qualifier == 'l') {
3195                                         qualifier = 'L';
3196                                         fmt++;
3197                                 }
3198                         }
3199                 }
3200
3201                 if (!*fmt)
3202                         break;
3203
3204                 if (*fmt == 'n') {
3205                         /* return number of characters read so far */
3206                         *va_arg(args, int *) = str - buf;
3207                         ++fmt;
3208                         continue;
3209                 }
3210
3211                 if (!*str)
3212                         break;
3213
3214                 base = 10;
3215                 is_sign = false;
3216
3217                 switch (*fmt++) {
3218                 case 'c':
3219                 {
3220                         char *s = (char *)va_arg(args, char*);
3221                         if (field_width == -1)
3222                                 field_width = 1;
3223                         do {
3224                                 *s++ = *str++;
3225                         } while (--field_width > 0 && *str);
3226                         num++;
3227                 }
3228                 continue;
3229                 case 's':
3230                 {
3231                         char *s = (char *)va_arg(args, char *);
3232                         if (field_width == -1)
3233                                 field_width = SHRT_MAX;
3234                         /* first, skip leading white space in buffer */
3235                         str = skip_spaces(str);
3236
3237                         /* now copy until next white space */
3238                         while (*str && !isspace(*str) && field_width--)
3239                                 *s++ = *str++;
3240                         *s = '\0';
3241                         num++;
3242                 }
3243                 continue;
3244                 /*
3245                  * Warning: This implementation of the '[' conversion specifier
3246                  * deviates from its glibc counterpart in the following ways:
3247                  * (1) It does NOT support ranges i.e. '-' is NOT a special
3248                  *     character
3249                  * (2) It cannot match the closing bracket ']' itself
3250                  * (3) A field width is required
3251                  * (4) '%*[' (discard matching input) is currently not supported
3252                  *
3253                  * Example usage:
3254                  * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3255                  *              buf1, buf2, buf3);
3256                  * if (ret < 3)
3257                  *    // etc..
3258                  */
3259                 case '[':
3260                 {
3261                         char *s = (char *)va_arg(args, char *);
3262                         DECLARE_BITMAP(set, 256) = {0};
3263                         unsigned int len = 0;
3264                         bool negate = (*fmt == '^');
3265
3266                         /* field width is required */
3267                         if (field_width == -1)
3268                                 return num;
3269
3270                         if (negate)
3271                                 ++fmt;
3272
3273                         for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3274                                 set_bit((u8)*fmt, set);
3275
3276                         /* no ']' or no character set found */
3277                         if (!*fmt || !len)
3278                                 return num;
3279                         ++fmt;
3280
3281                         if (negate) {
3282                                 bitmap_complement(set, set, 256);
3283                                 /* exclude null '\0' byte */
3284                                 clear_bit(0, set);
3285                         }
3286
3287                         /* match must be non-empty */
3288                         if (!test_bit((u8)*str, set))
3289                                 return num;
3290
3291                         while (test_bit((u8)*str, set) && field_width--)
3292                                 *s++ = *str++;
3293                         *s = '\0';
3294                         ++num;
3295                 }
3296                 continue;
3297                 case 'o':
3298                         base = 8;
3299                         break;
3300                 case 'x':
3301                 case 'X':
3302                         base = 16;
3303                         break;
3304                 case 'i':
3305                         base = 0;
3306                         /* fall through */
3307                 case 'd':
3308                         is_sign = true;
3309                         /* fall through */
3310                 case 'u':
3311                         break;
3312                 case '%':
3313                         /* looking for '%' in str */
3314                         if (*str++ != '%')
3315                                 return num;
3316                         continue;
3317                 default:
3318                         /* invalid format; stop here */
3319                         return num;
3320                 }
3321
3322                 /* have some sort of integer conversion.
3323                  * first, skip white space in buffer.
3324                  */
3325                 str = skip_spaces(str);
3326
3327                 digit = *str;
3328                 if (is_sign && digit == '-')
3329                         digit = *(str + 1);
3330
3331                 if (!digit
3332                     || (base == 16 && !isxdigit(digit))
3333                     || (base == 10 && !isdigit(digit))
3334                     || (base == 8 && (!isdigit(digit) || digit > '7'))
3335                     || (base == 0 && !isdigit(digit)))
3336                         break;
3337
3338                 if (is_sign)
3339                         val.s = qualifier != 'L' ?
3340                                 simple_strtol(str, &next, base) :
3341                                 simple_strtoll(str, &next, base);
3342                 else
3343                         val.u = qualifier != 'L' ?
3344                                 simple_strtoul(str, &next, base) :
3345                                 simple_strtoull(str, &next, base);
3346
3347                 if (field_width > 0 && next - str > field_width) {
3348                         if (base == 0)
3349                                 _parse_integer_fixup_radix(str, &base);
3350                         while (next - str > field_width) {
3351                                 if (is_sign)
3352                                         val.s = div_s64(val.s, base);
3353                                 else
3354                                         val.u = div_u64(val.u, base);
3355                                 --next;
3356                         }
3357                 }
3358
3359                 switch (qualifier) {
3360                 case 'H':       /* that's 'hh' in format */
3361                         if (is_sign)
3362                                 *va_arg(args, signed char *) = val.s;
3363                         else
3364                                 *va_arg(args, unsigned char *) = val.u;
3365                         break;
3366                 case 'h':
3367                         if (is_sign)
3368                                 *va_arg(args, short *) = val.s;
3369                         else
3370                                 *va_arg(args, unsigned short *) = val.u;
3371                         break;
3372                 case 'l':
3373                         if (is_sign)
3374                                 *va_arg(args, long *) = val.s;
3375                         else
3376                                 *va_arg(args, unsigned long *) = val.u;
3377                         break;
3378                 case 'L':
3379                         if (is_sign)
3380                                 *va_arg(args, long long *) = val.s;
3381                         else
3382                                 *va_arg(args, unsigned long long *) = val.u;
3383                         break;
3384                 case 'z':
3385                         *va_arg(args, size_t *) = val.u;
3386                         break;
3387                 default:
3388                         if (is_sign)
3389                                 *va_arg(args, int *) = val.s;
3390                         else
3391                                 *va_arg(args, unsigned int *) = val.u;
3392                         break;
3393                 }
3394                 num++;
3395
3396                 if (!next)
3397                         break;
3398                 str = next;
3399         }
3400
3401         return num;
3402 }
3403 EXPORT_SYMBOL(vsscanf);
3404
3405 /**
3406  * sscanf - Unformat a buffer into a list of arguments
3407  * @buf:        input buffer
3408  * @fmt:        formatting of buffer
3409  * @...:        resulting arguments
3410  */
3411 int sscanf(const char *buf, const char *fmt, ...)
3412 {
3413         va_list args;
3414         int i;
3415
3416         va_start(args, fmt);
3417         i = vsscanf(buf, fmt, args);
3418         va_end(args);
3419
3420         return i;
3421 }
3422 EXPORT_SYMBOL(sscanf);