lib/vsprintf.c

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  56  * This function is obsolete.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