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/build_bug.h>
  21 #include <linux/clk.h>
  22 #include <linux/clk-provider.h>
  23 #include <linux/module.h>       /* for KSYM_SYMBOL_LEN */
  24 #include <linux/types.h>
  25 #include <linux/string.h>
  26 #include <linux/ctype.h>
  27 #include <linux/kernel.h>
  28 #include <linux/kallsyms.h>
  29 #include <linux/math64.h>
  30 #include <linux/uaccess.h>
  31 #include <linux/ioport.h>
  32 #include <linux/dcache.h>
  33 #include <linux/cred.h>
  34 #include <linux/rtc.h>
  35 #include <linux/uuid.h>
  36 #include <linux/of.h>
  37 #include <net/addrconf.h>
  38 #include <linux/siphash.h>
  39 #include <linux/compiler.h>
  40 #ifdef CONFIG_BLOCK
  41 #include <linux/blkdev.h>
  42 #endif
  43
  44 #include "../mm/internal.h"     /* For the trace_print_flags arrays */
  45
  46 #include <asm/page.h>           /* for PAGE_SIZE */
  47 #include <asm/byteorder.h>      /* cpu_to_le16 */
  48
  49 #include <linux/string_helpers.h>
  50 #include "kstrtox.h"
  51
  52 /**
  53  * simple_strtoull - convert a string to an unsigned long long
  54  * @cp: The start of the string
  55  * @endp: A pointer to the end of the parsed string will be placed here
  56  * @base: The number base to use
  57  *
  58  * This function is obsolete. Please use kstrtoull instead.
  59  */
  60 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
  61 {
  62         unsigned long long result;
  63         unsigned int rv;
  64
  65         cp = _parse_integer_fixup_radix(cp, &base);
  66         rv = _parse_integer(cp, base, &result);
  67         /* FIXME */
  68         cp += (rv & ~KSTRTOX_OVERFLOW);
  69
  70         if (endp)
  71                 *endp = (char *)cp;
  72
  73         return result;
  74 }
  75 EXPORT_SYMBOL(simple_strtoull);
  76
  77 /**
  78  * simple_strtoul - convert a string to an unsigned long
  79  * @cp: The start of the string
  80  * @endp: A pointer to the end of the parsed string will be placed here
  81  * @base: The number base to use
  82  *
  83  * This function is obsolete. Please use kstrtoul instead.
  84  */
  85 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
  86 {
  87         return simple_strtoull(cp, endp, base);
  88 }
  89 EXPORT_SYMBOL(simple_strtoul);
  90
  91 /**
  92  * simple_strtol - convert a string to a signed long
  93  * @cp: The start of the string
  94  * @endp: A pointer to the end of the parsed string will be placed here
  95  * @base: The number base to use
  96  *
  97  * This function is obsolete. Please use kstrtol instead.
  98  */
  99 long simple_strtol(const char *cp, char **endp, unsigned int base)
 100 {
 101         if (*cp == '-')
 102                 return -simple_strtoul(cp + 1, endp, base);
 103
 104         return simple_strtoul(cp, endp, base);
 105 }
 106 EXPORT_SYMBOL(simple_strtol);
 107
 108 /**
 109  * simple_strtoll - convert a string to a signed long long
 110  * @cp: The start of the string
 111  * @endp: A pointer to the end of the parsed string will be placed here
 112  * @base: The number base to use
 113  *
 114  * This function is obsolete. Please use kstrtoll instead.
 115  */
 116 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
 117 {
 118         if (*cp == '-')
 119                 return -simple_strtoull(cp + 1, endp, base);
 120
 121         return simple_strtoull(cp, endp, base);
 122 }
 123 EXPORT_SYMBOL(simple_strtoll);
 124
 125 static noinline_for_stack
 126 int skip_atoi(const char **s)
 127 {
 128         int i = 0;
 129
 130         do {
 131                 i = i*10 + *((*s)++) - '0';
 132         } while (isdigit(**s));
 133
 134         return i;
 135 }
 136
 137 /*
 138  * Decimal conversion is by far the most typical, and is used for
 139  * /proc and /sys data. This directly impacts e.g. top performance
 140  * with many processes running. We optimize it for speed by emitting
 141  * two characters at a time, using a 200 byte lookup table. This
 142  * roughly halves the number of multiplications compared to computing
 143  * the digits one at a time. Implementation strongly inspired by the
 144  * previous version, which in turn used ideas described at
 145  * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
 146  * from the author, Douglas W. Jones).
 147  *
 148  * It turns out there is precisely one 26 bit fixed-point
 149  * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
 150  * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
 151  * range happens to be somewhat larger (x <= 1073741898), but that's
 152  * irrelevant for our purpose.
 153  *
 154  * For dividing a number in the range [10^4, 10^6-1] by 100, we still
 155  * need a 32x32->64 bit multiply, so we simply use the same constant.
 156  *
 157  * For dividing a number in the range [100, 10^4-1] by 100, there are
 158  * several options. The simplest is (x * 0x147b) >> 19, which is valid
 159  * for all x <= 43698.
 160  */
 161
 162 static const u16 decpair[100] = {
 163 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
 164         _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
 165         _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
 166         _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
 167         _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
 168         _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
 169         _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
 170         _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
 171         _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
 172         _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
 173         _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
 174 #undef _
 175 };
 176
 177 /*
 178  * This will print a single '0' even if r == 0, since we would
 179  * immediately jump to out_r where two 0s would be written but only
 180  * one of them accounted for in buf. This is needed by ip4_string
 181  * below. All other callers pass a non-zero value of r.
 182 */
 183 static noinline_for_stack
 184 char *put_dec_trunc8(char *buf, unsigned r)
 185 {
 186         unsigned q;
 187
 188         /* 1 <= r < 10^8 */
 189         if (r < 100)
 190                 goto out_r;
 191
 192         /* 100 <= r < 10^8 */
 193         q = (r * (u64)0x28f5c29) >> 32;
 194         *((u16 *)buf) = decpair[r - 100*q];
 195         buf += 2;
 196
 197         /* 1 <= q < 10^6 */
 198         if (q < 100)
 199                 goto out_q;
 200
 201         /*  100 <= q < 10^6 */
 202         r = (q * (u64)0x28f5c29) >> 32;
 203         *((u16 *)buf) = decpair[q - 100*r];
 204         buf += 2;
 205
 206         /* 1 <= r < 10^4 */
 207         if (r < 100)
 208                 goto out_r;
 209
 210         /* 100 <= r < 10^4 */
 211         q = (r * 0x147b) >> 19;
 212         *((u16 *)buf) = decpair[r - 100*q];
 213         buf += 2;
 214 out_q:
 215         /* 1 <= q < 100 */
 216         r = q;
 217 out_r:
 218         /* 1 <= r < 100 */
 219         *((u16 *)buf) = decpair[r];
 220         buf += r < 10 ? 1 : 2;
 221         return buf;
 222 }
 223
 224 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
 225 static noinline_for_stack
 226 char *put_dec_full8(char *buf, unsigned r)
 227 {
 228         unsigned q;
 229
 230         /* 0 <= r < 10^8 */
 231         q = (r * (u64)0x28f5c29) >> 32;
 232         *((u16 *)buf) = decpair[r - 100*q];
 233         buf += 2;
 234
 235         /* 0 <= q < 10^6 */
 236         r = (q * (u64)0x28f5c29) >> 32;
 237         *((u16 *)buf) = decpair[q - 100*r];
 238         buf += 2;
 239
 240         /* 0 <= r < 10^4 */
 241         q = (r * 0x147b) >> 19;
 242         *((u16 *)buf) = decpair[r - 100*q];
 243         buf += 2;
 244
 245         /* 0 <= q < 100 */
 246         *((u16 *)buf) = decpair[q];
 247         buf += 2;
 248         return buf;
 249 }
 250
 251 static noinline_for_stack
 252 char *put_dec(char *buf, unsigned long long n)
 253 {
 254         if (n >= 100*1000*1000)
 255                 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
 256         /* 1 <= n <= 1.6e11 */
 257         if (n >= 100*1000*1000)
 258                 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
 259         /* 1 <= n < 1e8 */
 260         return put_dec_trunc8(buf, n);
 261 }
 262
 263 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
 264
 265 static void
 266 put_dec_full4(char *buf, unsigned r)
 267 {
 268         unsigned q;
 269
 270         /* 0 <= r < 10^4 */
 271         q = (r * 0x147b) >> 19;
 272         *((u16 *)buf) = decpair[r - 100*q];
 273         buf += 2;
 274         /* 0 <= q < 100 */
 275         *((u16 *)buf) = decpair[q];
 276 }
 277
 278 /*
 279  * Call put_dec_full4 on x % 10000, return x / 10000.
 280  * The approximation x/10000 == (x * 0x346DC5D7) >> 43
 281  * holds for all x < 1,128,869,999.  The largest value this
 282  * helper will ever be asked to convert is 1,125,520,955.
 283  * (second call in the put_dec code, assuming n is all-ones).
 284  */
 285 static noinline_for_stack
 286 unsigned put_dec_helper4(char *buf, unsigned x)
 287 {
 288         uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
 289
 290         put_dec_full4(buf, x - q * 10000);
 291         return q;
 292 }
 293
 294 /* Based on code by Douglas W. Jones found at
 295  * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
 296  * (with permission from the author).
 297  * Performs no 64-bit division and hence should be fast on 32-bit machines.
 298  */
 299 static
 300 char *put_dec(char *buf, unsigned long long n)
 301 {
 302         uint32_t d3, d2, d1, q, h;
 303
 304         if (n < 100*1000*1000)
 305                 return put_dec_trunc8(buf, n);
 306
 307         d1  = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
 308         h   = (n >> 32);
 309         d2  = (h      ) & 0xffff;
 310         d3  = (h >> 16); /* implicit "& 0xffff" */
 311
 312         /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
 313              = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
 314         q   = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
 315         q = put_dec_helper4(buf, q);
 316
 317         q += 7671 * d3 + 9496 * d2 + 6 * d1;
 318         q = put_dec_helper4(buf+4, q);
 319
 320         q += 4749 * d3 + 42 * d2;
 321         q = put_dec_helper4(buf+8, q);
 322
 323         q += 281 * d3;
 324         buf += 12;
 325         if (q)
 326                 buf = put_dec_trunc8(buf, q);
 327         else while (buf[-1] == '0')
 328                 --buf;
 329
 330         return buf;
 331 }
 332
 333 #endif
 334
 335 /*
 336  * Convert passed number to decimal string.
 337  * Returns the length of string.  On buffer overflow, returns 0.
 338  *
 339  * If speed is not important, use snprintf(). It's easy to read the code.
 340  */
 341 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
 342 {
 343         /* put_dec requires 2-byte alignment of the buffer. */
 344         char tmp[sizeof(num) * 3] __aligned(2);
 345         int idx, len;
 346
 347         /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
 348         if (num <= 9) {
 349                 tmp[0] = '0' + num;
 350                 len = 1;
 351         } else {
 352                 len = put_dec(tmp, num) - tmp;
 353         }
 354
 355         if (len > size || width > size)
 356                 return 0;
 357
 358         if (width > len) {
 359                 width = width - len;
 360                 for (idx = 0; idx < width; idx++)
 361                         buf[idx] = ' ';
 362         } else {
 363                 width = 0;
 364         }
 365
 366         for (idx = 0; idx < len; ++idx)
 367                 buf[idx + width] = tmp[len - idx - 1];
 368
 369         return len + width;
 370 }
 371
 372 #define SIGN    1               /* unsigned/signed, must be 1 */
 373 #define LEFT    2               /* left justified */
 374 #define PLUS    4               /* show plus */
 375 #define SPACE   8               /* space if plus */
 376 #define ZEROPAD 16              /* pad with zero, must be 16 == '0' - ' ' */
 377 #define SMALL   32              /* use lowercase in hex (must be 32 == 0x20) */
 378 #define SPECIAL 64              /* prefix hex with "0x", octal with "0" */
 379
 380 enum format_type {
 381         FORMAT_TYPE_NONE, /* Just a string part */
 382         FORMAT_TYPE_WIDTH,
 383         FORMAT_TYPE_PRECISION,
 384         FORMAT_TYPE_CHAR,
 385         FORMAT_TYPE_STR,
 386         FORMAT_TYPE_PTR,
 387         FORMAT_TYPE_PERCENT_CHAR,
 388         FORMAT_TYPE_INVALID,
 389         FORMAT_TYPE_LONG_LONG,
 390         FORMAT_TYPE_ULONG,
 391         FORMAT_TYPE_LONG,
 392         FORMAT_TYPE_UBYTE,
 393         FORMAT_TYPE_BYTE,
 394         FORMAT_TYPE_USHORT,
 395         FORMAT_TYPE_SHORT,
 396         FORMAT_TYPE_UINT,
 397         FORMAT_TYPE_INT,
 398         FORMAT_TYPE_SIZE_T,
 399         FORMAT_TYPE_PTRDIFF
 400 };
 401
 402 struct printf_spec {
 403         unsigned int    type:8;         /* format_type enum */
 404         signed int      field_width:24; /* width of output field */
 405         unsigned int    flags:8;        /* flags to number() */
 406         unsigned int    base:8;         /* number base, 8, 10 or 16 only */
 407         signed int      precision:16;   /* # of digits/chars */
 408 } __packed;
 409 static_assert(sizeof(struct printf_spec) == 8);
 410
 411 #define FIELD_WIDTH_MAX ((1 << 23) - 1)
 412 #define PRECISION_MAX ((1 << 15) - 1)
 413
 414 static noinline_for_stack
 415 char *number(char *buf, char *end, unsigned long long num,
 416              struct printf_spec spec)
 417 {
 418         /* put_dec requires 2-byte alignment of the buffer. */
 419         char tmp[3 * sizeof(num)] __aligned(2);
 420         char sign;
 421         char locase;
 422         int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 423         int i;
 424         bool is_zero = num == 0LL;
 425         int field_width = spec.field_width;
 426         int precision = spec.precision;
 427
 428         /* locase = 0 or 0x20. ORing digits or letters with 'locase'
 429          * produces same digits or (maybe lowercased) letters */
 430         locase = (spec.flags & SMALL);
 431         if (spec.flags & LEFT)
 432                 spec.flags &= ~ZEROPAD;
 433         sign = 0;
 434         if (spec.flags & SIGN) {
 435                 if ((signed long long)num < 0) {
 436                         sign = '-';
 437                         num = -(signed long long)num;
 438                         field_width--;
 439                 } else if (spec.flags & PLUS) {
 440                         sign = '+';
 441                         field_width--;
 442                 } else if (spec.flags & SPACE) {
 443                         sign = ' ';
 444                         field_width--;
 445                 }
 446         }
 447         if (need_pfx) {
 448                 if (spec.base == 16)
 449                         field_width -= 2;
 450                 else if (!is_zero)
 451                         field_width--;
 452         }
 453
 454         /* generate full string in tmp[], in reverse order */
 455         i = 0;
 456         if (num < spec.base)
 457                 tmp[i++] = hex_asc_upper[num] | locase;
 458         else if (spec.base != 10) { /* 8 or 16 */
 459                 int mask = spec.base - 1;
 460                 int shift = 3;
 461
 462                 if (spec.base == 16)
 463                         shift = 4;
 464                 do {
 465                         tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
 466                         num >>= shift;
 467                 } while (num);
 468         } else { /* base 10 */
 469                 i = put_dec(tmp, num) - tmp;
 470         }
 471
 472         /* printing 100 using %2d gives "100", not "00" */
 473         if (i > precision)
 474                 precision = i;
 475         /* leading space padding */
 476         field_width -= precision;
 477         if (!(spec.flags & (ZEROPAD | LEFT))) {
 478                 while (--field_width >= 0) {
 479                         if (buf < end)
 480                                 *buf = ' ';
 481                         ++buf;
 482                 }
 483         }
 484         /* sign */
 485         if (sign) {
 486                 if (buf < end)
 487                         *buf = sign;
 488                 ++buf;
 489         }
 490         /* "0x" / "0" prefix */
 491         if (need_pfx) {
 492                 if (spec.base == 16 || !is_zero) {
 493                         if (buf < end)
 494                                 *buf = '0';
 495                         ++buf;
 496                 }
 497                 if (spec.base == 16) {
 498                         if (buf < end)
 499                                 *buf = ('X' | locase);
 500                         ++buf;
 501                 }
 502         }
 503         /* zero or space padding */
 504         if (!(spec.flags & LEFT)) {
 505                 char c = ' ' + (spec.flags & ZEROPAD);
 506                 BUILD_BUG_ON(' ' + ZEROPAD != '0');
 507                 while (--field_width >= 0) {
 508                         if (buf < end)
 509                                 *buf = c;
 510                         ++buf;
 511                 }
 512         }
 513         /* hmm even more zero padding? */
 514         while (i <= --precision) {
 515                 if (buf < end)
 516                         *buf = '0';
 517                 ++buf;
 518         }
 519         /* actual digits of result */
 520         while (--i >= 0) {
 521                 if (buf < end)
 522                         *buf = tmp[i];
 523                 ++buf;
 524         }
 525         /* trailing space padding */
 526         while (--field_width >= 0) {
 527                 if (buf < end)
 528                         *buf = ' ';
 529                 ++buf;
 530         }
 531
 532         return buf;
 533 }
 534
 535 static noinline_for_stack
 536 char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
 537 {
 538         struct printf_spec spec;
 539
 540         spec.type = FORMAT_TYPE_PTR;
 541         spec.field_width = 2 + 2 * size;        /* 0x + hex */
 542         spec.flags = SPECIAL | SMALL | ZEROPAD;
 543         spec.base = 16;
 544         spec.precision = -1;
 545
 546         return number(buf, end, num, spec);
 547 }
 548
 549 static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
 550 {
 551         size_t size;
 552         if (buf >= end) /* nowhere to put anything */
 553                 return;
 554         size = end - buf;
 555         if (size <= spaces) {
 556                 memset(buf, ' ', size);
 557                 return;
 558         }
 559         if (len) {
 560                 if (len > size - spaces)
 561                         len = size - spaces;
 562                 memmove(buf + spaces, buf, len);
 563         }
 564         memset(buf, ' ', spaces);
 565 }
 566
 567 /*
 568  * Handle field width padding for a string.
 569  * @buf: current buffer position
 570  * @n: length of string
 571  * @end: end of output buffer
 572  * @spec: for field width and flags
 573  * Returns: new buffer position after padding.
 574  */
 575 static noinline_for_stack
 576 char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
 577 {
 578         unsigned spaces;
 579
 580         if (likely(n >= spec.field_width))
 581                 return buf;
 582         /* we want to pad the sucker */
 583         spaces = spec.field_width - n;
 584         if (!(spec.flags & LEFT)) {
 585                 move_right(buf - n, end, n, spaces);
 586                 return buf + spaces;
 587         }
 588         while (spaces--) {
 589                 if (buf < end)
 590                         *buf = ' ';
 591                 ++buf;
 592         }
 593         return buf;
 594 }
 595
 596 /* Handle string from a well known address. */
 597 static char *string_nocheck(char *buf, char *end, const char *s,
 598                             struct printf_spec spec)
 599 {
 600         int len = 0;
 601         size_t lim = spec.precision;
 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 /* Be careful: error messages must fit into the given buffer. */
 616 static char *error_string(char *buf, char *end, const char *s,
 617                           struct printf_spec spec)
 618 {
 619         /*
 620          * Hard limit to avoid a completely insane messages. It actually
 621          * works pretty well because most error messages are in
 622          * the many pointer format modifiers.
 623          */
 624         if (spec.precision == -1)
 625                 spec.precision = 2 * sizeof(void *);
 626
 627         return string_nocheck(buf, end, s, spec);
 628 }
 629
 630 /*
 631  * Do not call any complex external code here. Nested printk()/vsprintf()
 632  * might cause infinite loops. Failures might break printk() and would
 633  * be hard to debug.
 634  */
 635 static const char *check_pointer_msg(const void *ptr)
 636 {
 637         if (!ptr)
 638                 return "(null)";
 639
 640         if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
 641                 return "(efault)";
 642
 643         return NULL;
 644 }
 645
 646 static int check_pointer(char **buf, char *end, const void *ptr,
 647                          struct printf_spec spec)
 648 {
 649         const char *err_msg;
 650
 651         err_msg = check_pointer_msg(ptr);
 652         if (err_msg) {
 653                 *buf = error_string(*buf, end, err_msg, spec);
 654                 return -EFAULT;
 655         }
 656
 657         return 0;
 658 }
 659
 660 static noinline_for_stack
 661 char *string(char *buf, char *end, const char *s,
 662              struct printf_spec spec)
 663 {
 664         if (check_pointer(&buf, end, s, spec))
 665                 return buf;
 666
 667         return string_nocheck(buf, end, s, spec);
 668 }
 669
 670 static char *pointer_string(char *buf, char *end,
 671                             const void *ptr,
 672                             struct printf_spec spec)
 673 {
 674         spec.base = 16;
 675         spec.flags |= SMALL;
 676         if (spec.field_width == -1) {
 677                 spec.field_width = 2 * sizeof(ptr);
 678                 spec.flags |= ZEROPAD;
 679         }
 680
 681         return number(buf, end, (unsigned long int)ptr, spec);
 682 }
 683
 684 /* Make pointers available for printing early in the boot sequence. */
 685 static int debug_boot_weak_hash __ro_after_init;
 686
 687 static int __init debug_boot_weak_hash_enable(char *str)
 688 {
 689         debug_boot_weak_hash = 1;
 690         pr_info("debug_boot_weak_hash enabled\n");
 691         return 0;
 692 }
 693 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
 694
 695 static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
 696 static siphash_key_t ptr_key __read_mostly;
 697
 698 static void enable_ptr_key_workfn(struct work_struct *work)
 699 {
 700         get_random_bytes(&ptr_key, sizeof(ptr_key));
 701         /* Needs to run from preemptible context */
 702         static_branch_disable(&not_filled_random_ptr_key);
 703 }
 704
 705 static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
 706
 707 static void fill_random_ptr_key(struct random_ready_callback *unused)
 708 {
 709         /* This may be in an interrupt handler. */
 710         queue_work(system_unbound_wq, &enable_ptr_key_work);
 711 }
 712
 713 static struct random_ready_callback random_ready = {
 714         .func = fill_random_ptr_key
 715 };
 716
 717 static int __init initialize_ptr_random(void)
 718 {
 719         int key_size = sizeof(ptr_key);
 720         int ret;
 721
 722         /* Use hw RNG if available. */
 723         if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
 724                 static_branch_disable(&not_filled_random_ptr_key);
 725                 return 0;
 726         }
 727
 728         ret = add_random_ready_callback(&random_ready);
 729         if (!ret) {
 730                 return 0;
 731         } else if (ret == -EALREADY) {
 732                 /* This is in preemptible context */
 733                 enable_ptr_key_workfn(&enable_ptr_key_work);
 734                 return 0;
 735         }
 736
 737         return ret;
 738 }
 739 early_initcall(initialize_ptr_random);
 740
 741 /* Maps a pointer to a 32 bit unique identifier. */
 742 static char *ptr_to_id(char *buf, char *end, const void *ptr,
 743                        struct printf_spec spec)
 744 {
 745         const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
 746         unsigned long hashval;
 747
 748         /* When debugging early boot use non-cryptographically secure hash. */
 749         if (unlikely(debug_boot_weak_hash)) {
 750                 hashval = hash_long((unsigned long)ptr, 32);
 751                 return pointer_string(buf, end, (const void *)hashval, spec);
 752         }
 753
 754         if (static_branch_unlikely(&not_filled_random_ptr_key)) {
 755                 spec.field_width = 2 * sizeof(ptr);
 756                 /* string length must be less than default_width */
 757                 return error_string(buf, end, str, spec);
 758         }
 759
 760 #ifdef CONFIG_64BIT
 761         hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
 762         /*
 763          * Mask off the first 32 bits, this makes explicit that we have
 764          * modified the address (and 32 bits is plenty for a unique ID).
 765          */
 766         hashval = hashval & 0xffffffff;
 767 #else
 768         hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
 769 #endif
 770         return pointer_string(buf, end, (const void *)hashval, spec);
 771 }
 772
 773 int kptr_restrict __read_mostly;
 774
 775 static noinline_for_stack
 776 char *restricted_pointer(char *buf, char *end, const void *ptr,
 777                          struct printf_spec spec)
 778 {
 779         switch (kptr_restrict) {
 780         case 0:
 781                 /* Handle as %p, hash and do _not_ leak addresses. */
 782                 return ptr_to_id(buf, end, ptr, spec);
 783         case 1: {
 784                 const struct cred *cred;
 785
 786                 /*
 787                  * kptr_restrict==1 cannot be used in IRQ context
 788                  * because its test for CAP_SYSLOG would be meaningless.
 789                  */
 790                 if (in_irq() || in_serving_softirq() || in_nmi()) {
 791                         if (spec.field_width == -1)
 792                                 spec.field_width = 2 * sizeof(ptr);
 793                         return error_string(buf, end, "pK-error", spec);
 794                 }
 795
 796                 /*
 797                  * Only print the real pointer value if the current
 798                  * process has CAP_SYSLOG and is running with the
 799                  * same credentials it started with. This is because
 800                  * access to files is checked at open() time, but %pK
 801                  * checks permission at read() time. We don't want to
 802                  * leak pointer values if a binary opens a file using
 803                  * %pK and then elevates privileges before reading it.
 804                  */
 805                 cred = current_cred();
 806                 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
 807                     !uid_eq(cred->euid, cred->uid) ||
 808                     !gid_eq(cred->egid, cred->gid))
 809                         ptr = NULL;
 810                 break;
 811         }
 812         case 2:
 813         default:
 814                 /* Always print 0's for %pK */
 815                 ptr = NULL;
 816                 break;
 817         }
 818
 819         return pointer_string(buf, end, ptr, spec);
 820 }
 821
 822 static noinline_for_stack
 823 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
 824                   const char *fmt)
 825 {
 826         const char *array[4], *s;
 827         const struct dentry *p;
 828         int depth;
 829         int i, n;
 830
 831         switch (fmt[1]) {
 832                 case '2': case '3': case '4':
 833                         depth = fmt[1] - '0';
 834                         break;
 835                 default:
 836                         depth = 1;
 837         }
 838
 839         rcu_read_lock();
 840         for (i = 0; i < depth; i++, d = p) {
 841                 if (check_pointer(&buf, end, d, spec)) {
 842                         rcu_read_unlock();
 843                         return buf;
 844                 }
 845
 846                 p = READ_ONCE(d->d_parent);
 847                 array[i] = READ_ONCE(d->d_name.name);
 848                 if (p == d) {
 849                         if (i)
 850                                 array[i] = "";
 851                         i++;
 852                         break;
 853                 }
 854         }
 855         s = array[--i];
 856         for (n = 0; n != spec.precision; n++, buf++) {
 857                 char c = *s++;
 858                 if (!c) {
 859                         if (!i)
 860                                 break;
 861                         c = '/';
 862                         s = array[--i];
 863                 }
 864                 if (buf < end)
 865                         *buf = c;
 866         }
 867         rcu_read_unlock();
 868         return widen_string(buf, n, end, spec);
 869 }
 870
 871 #ifdef CONFIG_BLOCK
 872 static noinline_for_stack
 873 char *bdev_name(char *buf, char *end, struct block_device *bdev,
 874                 struct printf_spec spec, const char *fmt)
 875 {
 876         struct gendisk *hd;
 877
 878         if (check_pointer(&buf, end, bdev, spec))
 879                 return buf;
 880
 881         hd = bdev->bd_disk;
 882         buf = string(buf, end, hd->disk_name, spec);
 883         if (bdev->bd_part->partno) {
 884                 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
 885                         if (buf < end)
 886                                 *buf = 'p';
 887                         buf++;
 888                 }
 889                 buf = number(buf, end, bdev->bd_part->partno, spec);
 890         }
 891         return buf;
 892 }
 893 #endif
 894
 895 static noinline_for_stack
 896 char *symbol_string(char *buf, char *end, void *ptr,
 897                     struct printf_spec spec, const char *fmt)
 898 {
 899         unsigned long value;
 900 #ifdef CONFIG_KALLSYMS
 901         char sym[KSYM_SYMBOL_LEN];
 902 #endif
 903
 904         if (fmt[1] == 'R')
 905                 ptr = __builtin_extract_return_addr(ptr);
 906         value = (unsigned long)ptr;
 907
 908 #ifdef CONFIG_KALLSYMS
 909         if (*fmt == 'B')
 910                 sprint_backtrace(sym, value);
 911         else if (*fmt != 'f' && *fmt != 's')
 912                 sprint_symbol(sym, value);
 913         else
 914                 sprint_symbol_no_offset(sym, value);
 915
 916         return string_nocheck(buf, end, sym, spec);
 917 #else
 918         return special_hex_number(buf, end, value, sizeof(void *));
 919 #endif
 920 }
 921
 922 static const struct printf_spec default_str_spec = {
 923         .field_width = -1,
 924         .precision = -1,
 925 };
 926
 927 static const struct printf_spec default_flag_spec = {
 928         .base = 16,
 929         .precision = -1,
 930         .flags = SPECIAL | SMALL,
 931 };
 932
 933 static const struct printf_spec default_dec_spec = {
 934         .base = 10,
 935         .precision = -1,
 936 };
 937
 938 static const struct printf_spec default_dec02_spec = {
 939         .base = 10,
 940         .field_width = 2,
 941         .precision = -1,
 942         .flags = ZEROPAD,
 943 };
 944
 945 static const struct printf_spec default_dec04_spec = {
 946         .base = 10,
 947         .field_width = 4,
 948         .precision = -1,
 949         .flags = ZEROPAD,
 950 };
 951
 952 static noinline_for_stack
 953 char *resource_string(char *buf, char *end, struct resource *res,
 954                       struct printf_spec spec, const char *fmt)
 955 {
 956 #ifndef IO_RSRC_PRINTK_SIZE
 957 #define IO_RSRC_PRINTK_SIZE     6
 958 #endif
 959
 960 #ifndef MEM_RSRC_PRINTK_SIZE
 961 #define MEM_RSRC_PRINTK_SIZE    10
 962 #endif
 963         static const struct printf_spec io_spec = {
 964                 .base = 16,
 965                 .field_width = IO_RSRC_PRINTK_SIZE,
 966                 .precision = -1,
 967                 .flags = SPECIAL | SMALL | ZEROPAD,
 968         };
 969         static const struct printf_spec mem_spec = {
 970                 .base = 16,
 971                 .field_width = MEM_RSRC_PRINTK_SIZE,
 972                 .precision = -1,
 973                 .flags = SPECIAL | SMALL | ZEROPAD,
 974         };
 975         static const struct printf_spec bus_spec = {
 976                 .base = 16,
 977                 .field_width = 2,
 978                 .precision = -1,
 979                 .flags = SMALL | ZEROPAD,
 980         };
 981         static const struct printf_spec str_spec = {
 982                 .field_width = -1,
 983                 .precision = 10,
 984                 .flags = LEFT,
 985         };
 986
 987         /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
 988          * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
 989 #define RSRC_BUF_SIZE           ((2 * sizeof(resource_size_t)) + 4)
 990 #define FLAG_BUF_SIZE           (2 * sizeof(res->flags))
 991 #define DECODED_BUF_SIZE        sizeof("[mem - 64bit pref window disabled]")
 992 #define RAW_BUF_SIZE            sizeof("[mem - flags 0x]")
 993         char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
 994                      2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
 995
 996         char *p = sym, *pend = sym + sizeof(sym);
 997         int decode = (fmt[0] == 'R') ? 1 : 0;
 998         const struct printf_spec *specp;
 999
1000         if (check_pointer(&buf, end, res, spec))
1001                 return buf;
1002
1003         *p++ = '[';
1004         if (res->flags & IORESOURCE_IO) {
1005                 p = string_nocheck(p, pend, "io  ", str_spec);
1006                 specp = &io_spec;
1007         } else if (res->flags & IORESOURCE_MEM) {
1008                 p = string_nocheck(p, pend, "mem ", str_spec);
1009                 specp = &mem_spec;
1010         } else if (res->flags & IORESOURCE_IRQ) {
1011                 p = string_nocheck(p, pend, "irq ", str_spec);
1012                 specp = &default_dec_spec;
1013         } else if (res->flags & IORESOURCE_DMA) {
1014                 p = string_nocheck(p, pend, "dma ", str_spec);
1015                 specp = &default_dec_spec;
1016         } else if (res->flags & IORESOURCE_BUS) {
1017                 p = string_nocheck(p, pend, "bus ", str_spec);
1018                 specp = &bus_spec;
1019         } else {
1020                 p = string_nocheck(p, pend, "??? ", str_spec);
1021                 specp = &mem_spec;
1022                 decode = 0;
1023         }
1024         if (decode && res->flags & IORESOURCE_UNSET) {
1025                 p = string_nocheck(p, pend, "size ", str_spec);
1026                 p = number(p, pend, resource_size(res), *specp);
1027         } else {
1028                 p = number(p, pend, res->start, *specp);
1029                 if (res->start != res->end) {
1030                         *p++ = '-';
1031                         p = number(p, pend, res->end, *specp);
1032                 }
1033         }
1034         if (decode) {
1035                 if (res->flags & IORESOURCE_MEM_64)
1036                         p = string_nocheck(p, pend, " 64bit", str_spec);
1037                 if (res->flags & IORESOURCE_PREFETCH)
1038                         p = string_nocheck(p, pend, " pref", str_spec);
1039                 if (res->flags & IORESOURCE_WINDOW)
1040                         p = string_nocheck(p, pend, " window", str_spec);
1041                 if (res->flags & IORESOURCE_DISABLED)
1042                         p = string_nocheck(p, pend, " disabled", str_spec);
1043         } else {
1044                 p = string_nocheck(p, pend, " flags ", str_spec);
1045                 p = number(p, pend, res->flags, default_flag_spec);
1046         }
1047         *p++ = ']';
1048         *p = '\0';
1049
1050         return string_nocheck(buf, end, sym, spec);
1051 }
1052
1053 static noinline_for_stack
1054 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1055                  const char *fmt)
1056 {
1057         int i, len = 1;         /* if we pass '%ph[CDN]', field width remains
1058                                    negative value, fallback to the default */
1059         char separator;
1060
1061         if (spec.field_width == 0)
1062                 /* nothing to print */
1063                 return buf;
1064
1065         if (check_pointer(&buf, end, addr, spec))
1066                 return buf;
1067
1068         switch (fmt[1]) {
1069         case 'C':
1070                 separator = ':';
1071                 break;
1072         case 'D':
1073                 separator = '-';
1074                 break;
1075         case 'N':
1076                 separator = 0;
1077                 break;
1078         default:
1079                 separator = ' ';
1080                 break;
1081         }
1082
1083         if (spec.field_width > 0)
1084                 len = min_t(int, spec.field_width, 64);
1085
1086         for (i = 0; i < len; ++i) {
1087                 if (buf < end)
1088                         *buf = hex_asc_hi(addr[i]);
1089                 ++buf;
1090                 if (buf < end)
1091                         *buf = hex_asc_lo(addr[i]);
1092                 ++buf;
1093
1094                 if (separator && i != len - 1) {
1095                         if (buf < end)
1096                                 *buf = separator;
1097                         ++buf;
1098                 }
1099         }
1100
1101         return buf;
1102 }
1103
1104 static noinline_for_stack
1105 char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
1106                     struct printf_spec spec, const char *fmt)
1107 {
1108         const int CHUNKSZ = 32;
1109         int nr_bits = max_t(int, spec.field_width, 0);
1110         int i, chunksz;
1111         bool first = true;
1112
1113         if (check_pointer(&buf, end, bitmap, spec))
1114                 return buf;
1115
1116         /* reused to print numbers */
1117         spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
1118
1119         chunksz = nr_bits & (CHUNKSZ - 1);
1120         if (chunksz == 0)
1121                 chunksz = CHUNKSZ;
1122
1123         i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
1124         for (; i >= 0; i -= CHUNKSZ) {
1125                 u32 chunkmask, val;
1126                 int word, bit;
1127
1128                 chunkmask = ((1ULL << chunksz) - 1);
1129                 word = i / BITS_PER_LONG;
1130                 bit = i % BITS_PER_LONG;
1131                 val = (bitmap[word] >> bit) & chunkmask;
1132
1133                 if (!first) {
1134                         if (buf < end)
1135                                 *buf = ',';
1136                         buf++;
1137                 }
1138                 first = false;
1139
1140                 spec.field_width = DIV_ROUND_UP(chunksz, 4);
1141                 buf = number(buf, end, val, spec);
1142
1143                 chunksz = CHUNKSZ;
1144         }
1145         return buf;
1146 }
1147
1148 static noinline_for_stack
1149 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
1150                          struct printf_spec spec, const char *fmt)
1151 {
1152         int nr_bits = max_t(int, spec.field_width, 0);
1153         /* current bit is 'cur', most recently seen range is [rbot, rtop] */
1154         int cur, rbot, rtop;
1155         bool first = true;
1156
1157         if (check_pointer(&buf, end, bitmap, spec))
1158                 return buf;
1159
1160         rbot = cur = find_first_bit(bitmap, nr_bits);
1161         while (cur < nr_bits) {
1162                 rtop = cur;
1163                 cur = find_next_bit(bitmap, nr_bits, cur + 1);
1164                 if (cur < nr_bits && cur <= rtop + 1)
1165                         continue;
1166
1167                 if (!first) {
1168                         if (buf < end)
1169                                 *buf = ',';
1170                         buf++;
1171                 }
1172                 first = false;
1173
1174                 buf = number(buf, end, rbot, default_dec_spec);
1175                 if (rbot < rtop) {
1176                         if (buf < end)
1177                                 *buf = '-';
1178                         buf++;
1179
1180                         buf = number(buf, end, rtop, default_dec_spec);
1181                 }
1182
1183                 rbot = cur;
1184         }
1185         return buf;
1186 }
1187
1188 static noinline_for_stack
1189 char *mac_address_string(char *buf, char *end, u8 *addr,
1190                          struct printf_spec spec, const char *fmt)
1191 {
1192         char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
1193         char *p = mac_addr;
1194         int i;
1195         char separator;
1196         bool reversed = false;
1197
1198         if (check_pointer(&buf, end, addr, spec))
1199                 return buf;
1200
1201         switch (fmt[1]) {
1202         case 'F':
1203                 separator = '-';
1204                 break;
1205
1206         case 'R':
1207                 reversed = true;
1208                 /* fall through */
1209
1210         default:
1211                 separator = ':';
1212                 break;
1213         }
1214
1215         for (i = 0; i < 6; i++) {
1216                 if (reversed)
1217                         p = hex_byte_pack(p, addr[5 - i]);
1218                 else
1219                         p = hex_byte_pack(p, addr[i]);
1220
1221                 if (fmt[0] == 'M' && i != 5)
1222                         *p++ = separator;
1223         }
1224         *p = '\0';
1225
1226         return string_nocheck(buf, end, mac_addr, spec);
1227 }
1228
1229 static noinline_for_stack
1230 char *ip4_string(char *p, const u8 *addr, const char *fmt)
1231 {
1232         int i;
1233         bool leading_zeros = (fmt[0] == 'i');
1234         int index;
1235         int step;
1236
1237         switch (fmt[2]) {
1238         case 'h':
1239 #ifdef __BIG_ENDIAN
1240                 index = 0;
1241                 step = 1;
1242 #else
1243                 index = 3;
1244                 step = -1;
1245 #endif
1246                 break;
1247         case 'l':
1248                 index = 3;
1249                 step = -1;
1250                 break;
1251         case 'n':
1252         case 'b':
1253         default:
1254                 index = 0;
1255                 step = 1;
1256                 break;
1257         }
1258         for (i = 0; i < 4; i++) {
1259                 char temp[4] __aligned(2);      /* hold each IP quad in reverse order */
1260                 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1261                 if (leading_zeros) {
1262                         if (digits < 3)
1263                                 *p++ = '0';
1264                         if (digits < 2)
1265                                 *p++ = '0';
1266                 }
1267                 /* reverse the digits in the quad */
1268                 while (digits--)
1269                         *p++ = temp[digits];
1270                 if (i < 3)
1271                         *p++ = '.';
1272                 index += step;
1273         }
1274         *p = '\0';
1275
1276         return p;
1277 }
1278
1279 static noinline_for_stack
1280 char *ip6_compressed_string(char *p, const char *addr)
1281 {
1282         int i, j, range;
1283         unsigned char zerolength[8];
1284         int longest = 1;
1285         int colonpos = -1;
1286         u16 word;
1287         u8 hi, lo;
1288         bool needcolon = false;
1289         bool useIPv4;
1290         struct in6_addr in6;
1291
1292         memcpy(&in6, addr, sizeof(struct in6_addr));
1293
1294         useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1295
1296         memset(zerolength, 0, sizeof(zerolength));
1297
1298         if (useIPv4)
1299                 range = 6;
1300         else
1301                 range = 8;
1302
1303         /* find position of longest 0 run */
1304         for (i = 0; i < range; i++) {
1305                 for (j = i; j < range; j++) {
1306                         if (in6.s6_addr16[j] != 0)
1307                                 break;
1308                         zerolength[i]++;
1309                 }
1310         }
1311         for (i = 0; i < range; i++) {
1312                 if (zerolength[i] > longest) {
1313                         longest = zerolength[i];
1314                         colonpos = i;
1315                 }
1316         }
1317         if (longest == 1)               /* don't compress a single 0 */
1318                 colonpos = -1;
1319
1320         /* emit address */
1321         for (i = 0; i < range; i++) {
1322                 if (i == colonpos) {
1323                         if (needcolon || i == 0)
1324                                 *p++ = ':';
1325                         *p++ = ':';
1326                         needcolon = false;
1327                         i += longest - 1;
1328                         continue;
1329                 }
1330                 if (needcolon) {
1331                         *p++ = ':';
1332                         needcolon = false;
1333                 }
1334                 /* hex u16 without leading 0s */
1335                 word = ntohs(in6.s6_addr16[i]);
1336                 hi = word >> 8;
1337                 lo = word & 0xff;
1338                 if (hi) {
1339                         if (hi > 0x0f)
1340                                 p = hex_byte_pack(p, hi);
1341                         else
1342                                 *p++ = hex_asc_lo(hi);
1343                         p = hex_byte_pack(p, lo);
1344                 }
1345                 else if (lo > 0x0f)
1346                         p = hex_byte_pack(p, lo);
1347                 else
1348                         *p++ = hex_asc_lo(lo);
1349                 needcolon = true;
1350         }
1351
1352         if (useIPv4) {
1353                 if (needcolon)
1354                         *p++ = ':';
1355                 p = ip4_string(p, &in6.s6_addr[12], "I4");
1356         }
1357         *p = '\0';
1358
1359         return p;
1360 }
1361
1362 static noinline_for_stack
1363 char *ip6_string(char *p, const char *addr, const char *fmt)
1364 {
1365         int i;
1366
1367         for (i = 0; i < 8; i++) {
1368                 p = hex_byte_pack(p, *addr++);
1369                 p = hex_byte_pack(p, *addr++);
1370                 if (fmt[0] == 'I' && i != 7)
1371                         *p++ = ':';
1372         }
1373         *p = '\0';
1374
1375         return p;
1376 }
1377
1378 static noinline_for_stack
1379 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1380                       struct printf_spec spec, const char *fmt)
1381 {
1382         char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1383
1384         if (fmt[0] == 'I' && fmt[2] == 'c')
1385                 ip6_compressed_string(ip6_addr, addr);
1386         else
1387                 ip6_string(ip6_addr, addr, fmt);
1388
1389         return string_nocheck(buf, end, ip6_addr, spec);
1390 }
1391
1392 static noinline_for_stack
1393 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1394                       struct printf_spec spec, const char *fmt)
1395 {
1396         char ip4_addr[sizeof("255.255.255.255")];
1397
1398         ip4_string(ip4_addr, addr, fmt);
1399
1400         return string_nocheck(buf, end, ip4_addr, spec);
1401 }
1402
1403 static noinline_for_stack
1404 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1405                          struct printf_spec spec, const char *fmt)
1406 {
1407         bool have_p = false, have_s = false, have_f = false, have_c = false;
1408         char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1409                       sizeof(":12345") + sizeof("/123456789") +
1410                       sizeof("%1234567890")];
1411         char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1412         const u8 *addr = (const u8 *) &sa->sin6_addr;
1413         char fmt6[2] = { fmt[0], '6' };
1414         u8 off = 0;
1415
1416         fmt++;
1417         while (isalpha(*++fmt)) {
1418                 switch (*fmt) {
1419                 case 'p':
1420                         have_p = true;
1421                         break;
1422                 case 'f':
1423                         have_f = true;
1424                         break;
1425                 case 's':
1426                         have_s = true;
1427                         break;
1428                 case 'c':
1429                         have_c = true;
1430                         break;
1431                 }
1432         }
1433
1434         if (have_p || have_s || have_f) {
1435                 *p = '[';
1436                 off = 1;
1437         }
1438
1439         if (fmt6[0] == 'I' && have_c)
1440                 p = ip6_compressed_string(ip6_addr + off, addr);
1441         else
1442                 p = ip6_string(ip6_addr + off, addr, fmt6);
1443
1444         if (have_p || have_s || have_f)
1445                 *p++ = ']';
1446
1447         if (have_p) {
1448                 *p++ = ':';
1449                 p = number(p, pend, ntohs(sa->sin6_port), spec);
1450         }
1451         if (have_f) {
1452                 *p++ = '/';
1453                 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1454                                           IPV6_FLOWINFO_MASK), spec);
1455         }
1456         if (have_s) {
1457                 *p++ = '%';
1458                 p = number(p, pend, sa->sin6_scope_id, spec);
1459         }
1460         *p = '\0';
1461
1462         return string_nocheck(buf, end, ip6_addr, spec);
1463 }
1464
1465 static noinline_for_stack
1466 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1467                          struct printf_spec spec, const char *fmt)
1468 {
1469         bool have_p = false;
1470         char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1471         char *pend = ip4_addr + sizeof(ip4_addr);
1472         const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1473         char fmt4[3] = { fmt[0], '4', 0 };
1474
1475         fmt++;
1476         while (isalpha(*++fmt)) {
1477                 switch (*fmt) {
1478                 case 'p':
1479                         have_p = true;
1480                         break;
1481                 case 'h':
1482                 case 'l':
1483                 case 'n':
1484                 case 'b':
1485                         fmt4[2] = *fmt;
1486                         break;
1487                 }
1488         }
1489
1490         p = ip4_string(ip4_addr, addr, fmt4);
1491         if (have_p) {
1492                 *p++ = ':';
1493                 p = number(p, pend, ntohs(sa->sin_port), spec);
1494         }
1495         *p = '\0';
1496
1497         return string_nocheck(buf, end, ip4_addr, spec);
1498 }
1499
1500 static noinline_for_stack
1501 char *ip_addr_string(char *buf, char *end, const void *ptr,
1502                      struct printf_spec spec, const char *fmt)
1503 {
1504         char *err_fmt_msg;
1505
1506         if (check_pointer(&buf, end, ptr, spec))
1507                 return buf;
1508
1509         switch (fmt[1]) {
1510         case '6':
1511                 return ip6_addr_string(buf, end, ptr, spec, fmt);
1512         case '4':
1513                 return ip4_addr_string(buf, end, ptr, spec, fmt);
1514         case 'S': {
1515                 const union {
1516                         struct sockaddr         raw;
1517                         struct sockaddr_in      v4;
1518                         struct sockaddr_in6     v6;
1519                 } *sa = ptr;
1520
1521                 switch (sa->raw.sa_family) {
1522                 case AF_INET:
1523                         return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1524                 case AF_INET6:
1525                         return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1526                 default:
1527                         return error_string(buf, end, "(einval)", spec);
1528                 }}
1529         }
1530
1531         err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
1532         return error_string(buf, end, err_fmt_msg, spec);
1533 }
1534
1535 static noinline_for_stack
1536 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1537                      const char *fmt)
1538 {
1539         bool found = true;
1540         int count = 1;
1541         unsigned int flags = 0;
1542         int len;
1543
1544         if (spec.field_width == 0)
1545                 return buf;                             /* nothing to print */
1546
1547         if (check_pointer(&buf, end, addr, spec))
1548                 return buf;
1549
1550         do {
1551                 switch (fmt[count++]) {
1552                 case 'a':
1553                         flags |= ESCAPE_ANY;
1554                         break;
1555                 case 'c':
1556                         flags |= ESCAPE_SPECIAL;
1557                         break;
1558                 case 'h':
1559                         flags |= ESCAPE_HEX;
1560                         break;
1561                 case 'n':
1562                         flags |= ESCAPE_NULL;
1563                         break;
1564                 case 'o':
1565                         flags |= ESCAPE_OCTAL;
1566                         break;
1567                 case 'p':
1568                         flags |= ESCAPE_NP;
1569                         break;
1570                 case 's':
1571                         flags |= ESCAPE_SPACE;
1572                         break;
1573                 default:
1574                         found = false;
1575                         break;
1576                 }
1577         } while (found);
1578
1579         if (!flags)
1580                 flags = ESCAPE_ANY_NP;
1581
1582         len = spec.field_width < 0 ? 1 : spec.field_width;
1583
1584         /*
1585          * string_escape_mem() writes as many characters as it can to
1586          * the given buffer, and returns the total size of the output
1587          * had the buffer been big enough.
1588          */
1589         buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1590
1591         return buf;
1592 }
1593
1594 static char *va_format(char *buf, char *end, struct va_format *va_fmt,
1595                        struct printf_spec spec, const char *fmt)
1596 {
1597         va_list va;
1598
1599         if (check_pointer(&buf, end, va_fmt, spec))
1600                 return buf;
1601
1602         va_copy(va, *va_fmt->va);
1603         buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
1604         va_end(va);
1605
1606         return buf;
1607 }
1608
1609 static noinline_for_stack
1610 char *uuid_string(char *buf, char *end, const u8 *addr,
1611                   struct printf_spec spec, const char *fmt)
1612 {
1613         char uuid[UUID_STRING_LEN + 1];
1614         char *p = uuid;
1615         int i;
1616         const u8 *index = uuid_index;
1617         bool uc = false;
1618
1619         if (check_pointer(&buf, end, addr, spec))
1620                 return buf;
1621
1622         switch (*(++fmt)) {
1623         case 'L':
1624                 uc = true;              /* fall-through */
1625         case 'l':
1626                 index = guid_index;
1627                 break;
1628         case 'B':
1629                 uc = true;
1630                 break;
1631         }
1632
1633         for (i = 0; i < 16; i++) {
1634                 if (uc)
1635                         p = hex_byte_pack_upper(p, addr[index[i]]);
1636                 else
1637                         p = hex_byte_pack(p, addr[index[i]]);
1638                 switch (i) {
1639                 case 3:
1640                 case 5:
1641                 case 7:
1642                 case 9:
1643                         *p++ = '-';
1644                         break;
1645                 }
1646         }
1647
1648         *p = 0;
1649
1650         return string_nocheck(buf, end, uuid, spec);
1651 }
1652
1653 static noinline_for_stack
1654 char *netdev_bits(char *buf, char *end, const void *addr,
1655                   struct printf_spec spec,  const char *fmt)
1656 {
1657         unsigned long long num;
1658         int size;
1659
1660         if (check_pointer(&buf, end, addr, spec))
1661                 return buf;
1662
1663         switch (fmt[1]) {
1664         case 'F':
1665                 num = *(const netdev_features_t *)addr;
1666                 size = sizeof(netdev_features_t);
1667                 break;
1668         default:
1669                 return error_string(buf, end, "(%pN?)", spec);
1670         }
1671
1672         return special_hex_number(buf, end, num, size);
1673 }
1674
1675 static noinline_for_stack
1676 char *address_val(char *buf, char *end, const void *addr,
1677                   struct printf_spec spec, const char *fmt)
1678 {
1679         unsigned long long num;
1680         int size;
1681
1682         if (check_pointer(&buf, end, addr, spec))
1683                 return buf;
1684
1685         switch (fmt[1]) {
1686         case 'd':
1687                 num = *(const dma_addr_t *)addr;
1688                 size = sizeof(dma_addr_t);
1689                 break;
1690         case 'p':
1691         default:
1692                 num = *(const phys_addr_t *)addr;
1693                 size = sizeof(phys_addr_t);
1694                 break;
1695         }
1696
1697         return special_hex_number(buf, end, num, size);
1698 }
1699
1700 static noinline_for_stack
1701 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1702 {
1703         int year = tm->tm_year + (r ? 0 : 1900);
1704         int mon = tm->tm_mon + (r ? 0 : 1);
1705
1706         buf = number(buf, end, year, default_dec04_spec);
1707         if (buf < end)
1708                 *buf = '-';
1709         buf++;
1710
1711         buf = number(buf, end, mon, default_dec02_spec);
1712         if (buf < end)
1713                 *buf = '-';
1714         buf++;
1715
1716         return number(buf, end, tm->tm_mday, default_dec02_spec);
1717 }
1718
1719 static noinline_for_stack
1720 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1721 {
1722         buf = number(buf, end, tm->tm_hour, default_dec02_spec);
1723         if (buf < end)
1724                 *buf = ':';
1725         buf++;
1726
1727         buf = number(buf, end, tm->tm_min, default_dec02_spec);
1728         if (buf < end)
1729                 *buf = ':';
1730         buf++;
1731
1732         return number(buf, end, tm->tm_sec, default_dec02_spec);
1733 }
1734
1735 static noinline_for_stack
1736 char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
1737               struct printf_spec spec, const char *fmt)
1738 {
1739         bool have_t = true, have_d = true;
1740         bool raw = false;
1741         int count = 2;
1742
1743         if (check_pointer(&buf, end, tm, spec))
1744                 return buf;
1745
1746         switch (fmt[count]) {
1747         case 'd':
1748                 have_t = false;
1749                 count++;
1750                 break;
1751         case 't':
1752                 have_d = false;
1753                 count++;
1754                 break;
1755         }
1756
1757         raw = fmt[count] == 'r';
1758
1759         if (have_d)
1760                 buf = date_str(buf, end, tm, raw);
1761         if (have_d && have_t) {
1762                 /* Respect ISO 8601 */
1763                 if (buf < end)
1764                         *buf = 'T';
1765                 buf++;
1766         }
1767         if (have_t)
1768                 buf = time_str(buf, end, tm, raw);
1769
1770         return buf;
1771 }
1772
1773 static noinline_for_stack
1774 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
1775                     const char *fmt)
1776 {
1777         switch (fmt[1]) {
1778         case 'R':
1779                 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
1780         default:
1781                 return error_string(buf, end, "(%ptR?)", spec);
1782         }
1783 }
1784
1785 static noinline_for_stack
1786 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1787             const char *fmt)
1788 {
1789         if (!IS_ENABLED(CONFIG_HAVE_CLK))
1790                 return error_string(buf, end, "(%pC?)", spec);
1791
1792         if (check_pointer(&buf, end, clk, spec))
1793                 return buf;
1794
1795         switch (fmt[1]) {
1796         case 'n':
1797         default:
1798 #ifdef CONFIG_COMMON_CLK
1799                 return string(buf, end, __clk_get_name(clk), spec);
1800 #else
1801                 return error_string(buf, end, "(%pC?)", spec);
1802 #endif
1803         }
1804 }
1805
1806 static
1807 char *format_flags(char *buf, char *end, unsigned long flags,
1808                                         const struct trace_print_flags *names)
1809 {
1810         unsigned long mask;
1811
1812         for ( ; flags && names->name; names++) {
1813                 mask = names->mask;
1814                 if ((flags & mask) != mask)
1815                         continue;
1816
1817                 buf = string(buf, end, names->name, default_str_spec);
1818
1819                 flags &= ~mask;
1820                 if (flags) {
1821                         if (buf < end)
1822                                 *buf = '|';
1823                         buf++;
1824                 }
1825         }
1826
1827         if (flags)
1828                 buf = number(buf, end, flags, default_flag_spec);
1829
1830         return buf;
1831 }
1832
1833 static noinline_for_stack
1834 char *flags_string(char *buf, char *end, void *flags_ptr,
1835                    struct printf_spec spec, const char *fmt)
1836 {
1837         unsigned long flags;
1838         const struct trace_print_flags *names;
1839
1840         if (check_pointer(&buf, end, flags_ptr, spec))
1841                 return buf;
1842
1843         switch (fmt[1]) {
1844         case 'p':
1845                 flags = *(unsigned long *)flags_ptr;
1846                 /* Remove zone id */
1847                 flags &= (1UL << NR_PAGEFLAGS) - 1;
1848                 names = pageflag_names;
1849                 break;
1850         case 'v':
1851                 flags = *(unsigned long *)flags_ptr;
1852                 names = vmaflag_names;
1853                 break;
1854         case 'g':
1855                 flags = *(gfp_t *)flags_ptr;
1856                 names = gfpflag_names;
1857                 break;
1858         default:
1859                 return error_string(buf, end, "(%pG?)", spec);
1860         }
1861
1862         return format_flags(buf, end, flags, names);
1863 }
1864
1865 static const char *device_node_name_for_depth(const struct device_node *np, int depth)
1866 {
1867         for ( ; np && depth; depth--)
1868                 np = np->parent;
1869
1870         return kbasename(np->full_name);
1871 }
1872
1873 static noinline_for_stack
1874 char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end)
1875 {
1876         int depth;
1877         const struct device_node *parent = np->parent;
1878
1879         /* special case for root node */
1880         if (!parent)
1881                 return string_nocheck(buf, end, "/", default_str_spec);
1882
1883         for (depth = 0; parent->parent; depth++)
1884                 parent = parent->parent;
1885
1886         for ( ; depth >= 0; depth--) {
1887                 buf = string_nocheck(buf, end, "/", default_str_spec);
1888                 buf = string(buf, end, device_node_name_for_depth(np, depth),
1889                              default_str_spec);
1890         }
1891         return buf;
1892 }
1893
1894 static noinline_for_stack
1895 char *device_node_string(char *buf, char *end, struct device_node *dn,
1896                          struct printf_spec spec, const char *fmt)
1897 {
1898         char tbuf[sizeof("xxxx") + 1];
1899         const char *p;
1900         int ret;
1901         char *buf_start = buf;
1902         struct property *prop;
1903         bool has_mult, pass;
1904         static const struct printf_spec num_spec = {
1905                 .flags = SMALL,
1906                 .field_width = -1,
1907                 .precision = -1,
1908                 .base = 10,
1909         };
1910
1911         struct printf_spec str_spec = spec;
1912         str_spec.field_width = -1;
1913
1914         if (!IS_ENABLED(CONFIG_OF))
1915                 return error_string(buf, end, "(%pOF?)", spec);
1916
1917         if (check_pointer(&buf, end, dn, spec))
1918                 return buf;
1919
1920         /* simple case without anything any more format specifiers */
1921         fmt++;
1922         if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
1923                 fmt = "f";
1924
1925         for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
1926                 int precision;
1927                 if (pass) {
1928                         if (buf < end)
1929                                 *buf = ':';
1930                         buf++;
1931                 }
1932
1933                 switch (*fmt) {
1934                 case 'f':       /* full_name */
1935                         buf = device_node_gen_full_name(dn, buf, end);
1936                         break;
1937                 case 'n':       /* name */
1938                         p = kbasename(of_node_full_name(dn));
1939                         precision = str_spec.precision;
1940                         str_spec.precision = strchrnul(p, '@') - p;
1941                         buf = string(buf, end, p, str_spec);
1942                         str_spec.precision = precision;
1943                         break;
1944                 case 'p':       /* phandle */
1945                         buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
1946                         break;
1947                 case 'P':       /* path-spec */
1948                         p = kbasename(of_node_full_name(dn));
1949                         if (!p[1])
1950                                 p = "/";
1951                         buf = string(buf, end, p, str_spec);
1952                         break;
1953                 case 'F':       /* flags */
1954                         tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
1955                         tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
1956                         tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
1957                         tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
1958                         tbuf[4] = 0;
1959                         buf = string_nocheck(buf, end, tbuf, str_spec);
1960                         break;
1961                 case 'c':       /* major compatible string */
1962                         ret = of_property_read_string(dn, "compatible", &p);
1963                         if (!ret)
1964                                 buf = string(buf, end, p, str_spec);
1965                         break;
1966                 case 'C':       /* full compatible string */
1967                         has_mult = false;
1968                         of_property_for_each_string(dn, "compatible", prop, p) {
1969                                 if (has_mult)
1970                                         buf = string_nocheck(buf, end, ",", str_spec);
1971                                 buf = string_nocheck(buf, end, "\"", str_spec);
1972                                 buf = string(buf, end, p, str_spec);
1973                                 buf = string_nocheck(buf, end, "\"", str_spec);
1974
1975                                 has_mult = true;
1976                         }
1977                         break;
1978                 default:
1979                         break;
1980                 }
1981         }
1982
1983         return widen_string(buf, buf - buf_start, end, spec);
1984 }
1985
1986 static char *kobject_string(char *buf, char *end, void *ptr,
1987                             struct printf_spec spec, const char *fmt)
1988 {
1989         switch (fmt[1]) {
1990         case 'F':
1991                 return device_node_string(buf, end, ptr, spec, fmt + 1);
1992         }
1993
1994         return error_string(buf, end, "(%pO?)", spec);
1995 }
1996
1997 /*
1998  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
1999  * by an extra set of alphanumeric characters that are extended format
2000  * specifiers.
2001  *
2002  * Please update scripts/checkpatch.pl when adding/removing conversion
2003  * characters.  (Search for "check for vsprintf extension").
2004  *
2005  * Right now we handle:
2006  *
2007  * - 'S' For symbolic direct pointers (or function descriptors) with offset
2008  * - 's' For symbolic direct pointers (or function descriptors) without offset
2009  * - 'F' Same as 'S'
2010  * - 'f' Same as 's'
2011  * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
2012  * - 'B' For backtraced symbolic direct pointers with offset
2013  * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
2014  * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
2015  * - 'b[l]' For a bitmap, the number of bits is determined by the field
2016  *       width which must be explicitly specified either as part of the
2017  *       format string '%32b[l]' or through '%*b[l]', [l] selects
2018  *       range-list format instead of hex format
2019  * - 'M' For a 6-byte MAC address, it prints the address in the
2020  *       usual colon-separated hex notation
2021  * - 'm' For a 6-byte MAC address, it prints the hex address without colons
2022  * - 'MF' For a 6-byte MAC FDDI address, it prints the address
2023  *       with a dash-separated hex notation
2024  * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
2025  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
2026  *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
2027  *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
2028  *       [S][pfs]
2029  *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2030  *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2031  * - 'i' [46] for 'raw' IPv4/IPv6 addresses
2032  *       IPv6 omits the colons (01020304...0f)
2033  *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
2034  *       [S][pfs]
2035  *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2036  *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2037  * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
2038  * - 'I[6S]c' for IPv6 addresses printed as specified by
2039  *       http://tools.ietf.org/html/rfc5952
2040  * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
2041  *                of the following flags (see string_escape_mem() for the
2042  *                details):
2043  *                  a - ESCAPE_ANY
2044  *                  c - ESCAPE_SPECIAL
2045  *                  h - ESCAPE_HEX
2046  *                  n - ESCAPE_NULL
2047  *                  o - ESCAPE_OCTAL
2048  *                  p - ESCAPE_NP
2049  *                  s - ESCAPE_SPACE
2050  *                By default ESCAPE_ANY_NP is used.
2051  * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
2052  *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
2053  *       Options for %pU are:
2054  *         b big endian lower case hex (default)
2055  *         B big endian UPPER case hex
2056  *         l little endian lower case hex
2057  *         L little endian UPPER case hex
2058  *           big endian output byte order is:
2059  *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
2060  *           little endian output byte order is:
2061  *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
2062  * - 'V' For a struct va_format which contains a format string * and va_list *,
2063  *       call vsnprintf(->format, *->va_list).
2064  *       Implements a "recursive vsnprintf".
2065  *       Do not use this feature without some mechanism to verify the
2066  *       correctness of the format string and va_list arguments.
2067  * - 'K' For a kernel pointer that should be hidden from unprivileged users
2068  * - 'NF' For a netdev_features_t
2069  * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
2070  *            a certain separator (' ' by default):
2071  *              C colon
2072  *              D dash
2073  *              N no separator
2074  *            The maximum supported length is 64 bytes of the input. Consider
2075  *            to use print_hex_dump() for the larger input.
2076  * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
2077  *           (default assumed to be phys_addr_t, passed by reference)
2078  * - 'd[234]' For a dentry name (optionally 2-4 last components)
2079  * - 'D[234]' Same as 'd' but for a struct file
2080  * - 'g' For block_device name (gendisk + partition number)
2081  * - 't[R][dt][r]' For time and date as represented:
2082  *      R    struct rtc_time
2083  * - 'C' For a clock, it prints the name (Common Clock Framework) or address
2084  *       (legacy clock framework) of the clock
2085  * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
2086  *        (legacy clock framework) of the clock
2087  * - 'G' For flags to be printed as a collection of symbolic strings that would
2088  *       construct the specific value. Supported flags given by option:
2089  *       p page flags (see struct page) given as pointer to unsigned long
2090  *       g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
2091  *       v vma flags (VM_*) given as pointer to unsigned long
2092  * - 'OF[fnpPcCF]'  For a device tree object
2093  *                  Without any optional arguments prints the full_name
2094  *                  f device node full_name
2095  *                  n device node name
2096  *                  p device node phandle
2097  *                  P device node path spec (name + @unit)
2098  *                  F device node flags
2099  *                  c major compatible string
2100  *                  C full compatible string
2101  * - 'x' For printing the address. Equivalent to "%lx".
2102  *
2103  * ** When making changes please also update:
2104  *      Documentation/core-api/printk-formats.rst
2105  *
2106  * Note: The default behaviour (unadorned %p) is to hash the address,
2107  * rendering it useful as a unique identifier.
2108  */
2109 static noinline_for_stack
2110 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
2111               struct printf_spec spec)
2112 {
2113         switch (*fmt) {
2114         case 'F':
2115         case 'f':
2116         case 'S':
2117         case 's':
2118                 ptr = dereference_symbol_descriptor(ptr);
2119                 /* Fallthrough */
2120         case 'B':
2121                 return symbol_string(buf, end, ptr, spec, fmt);
2122         case 'R':
2123         case 'r':
2124                 return resource_string(buf, end, ptr, spec, fmt);
2125         case 'h':
2126                 return hex_string(buf, end, ptr, spec, fmt);
2127         case 'b':
2128                 switch (fmt[1]) {
2129                 case 'l':
2130                         return bitmap_list_string(buf, end, ptr, spec, fmt);
2131                 default:
2132                         return bitmap_string(buf, end, ptr, spec, fmt);
2133                 }
2134         case 'M':                       /* Colon separated: 00:01:02:03:04:05 */
2135         case 'm':                       /* Contiguous: 000102030405 */
2136                                         /* [mM]F (FDDI) */
2137                                         /* [mM]R (Reverse order; Bluetooth) */
2138                 return mac_address_string(buf, end, ptr, spec, fmt);
2139         case 'I':                       /* Formatted IP supported
2140                                          * 4:   1.2.3.4
2141                                          * 6:   0001:0203:...:0708
2142                                          * 6c:  1::708 or 1::1.2.3.4
2143                                          */
2144         case 'i':                       /* Contiguous:
2145                                          * 4:   001.002.003.004
2146                                          * 6:   000102...0f
2147                                          */
2148                 return ip_addr_string(buf, end, ptr, spec, fmt);
2149         case 'E':
2150                 return escaped_string(buf, end, ptr, spec, fmt);
2151         case 'U':
2152                 return uuid_string(buf, end, ptr, spec, fmt);
2153         case 'V':
2154                 return va_format(buf, end, ptr, spec, fmt);
2155         case 'K':
2156                 return restricted_pointer(buf, end, ptr, spec);
2157         case 'N':
2158                 return netdev_bits(buf, end, ptr, spec, fmt);
2159         case 'a':
2160                 return address_val(buf, end, ptr, spec, fmt);
2161         case 'd':
2162                 return dentry_name(buf, end, ptr, spec, fmt);
2163         case 't':
2164                 return time_and_date(buf, end, ptr, spec, fmt);
2165         case 'C':
2166                 return clock(buf, end, ptr, spec, fmt);
2167         case 'D':
2168                 return dentry_name(buf, end,
2169                                    ((const struct file *)ptr)->f_path.dentry,
2170                                    spec, fmt);
2171 #ifdef CONFIG_BLOCK
2172         case 'g':
2173                 return bdev_name(buf, end, ptr, spec, fmt);
2174 #endif
2175
2176         case 'G':
2177                 return flags_string(buf, end, ptr, spec, fmt);
2178         case 'O':
2179                 return kobject_string(buf, end, ptr, spec, fmt);
2180         case 'x':
2181                 return pointer_string(buf, end, ptr, spec);
2182         }
2183
2184         /* default is to _not_ leak addresses, hash before printing */
2185         return ptr_to_id(buf, end, ptr, spec);
2186 }
2187
2188 /*
2189  * Helper function to decode printf style format.
2190  * Each call decode a token from the format and return the
2191  * number of characters read (or likely the delta where it wants
2192  * to go on the next call).
2193  * The decoded token is returned through the parameters
2194  *
2195  * 'h', 'l', or 'L' for integer fields
2196  * 'z' support added 23/7/1999 S.H.
2197  * 'z' changed to 'Z' --davidm 1/25/99
2198  * 'Z' changed to 'z' --adobriyan 2017-01-25
2199  * 't' added for ptrdiff_t
2200  *
2201  * @fmt: the format string
2202  * @type of the token returned
2203  * @flags: various flags such as +, -, # tokens..
2204  * @field_width: overwritten width
2205  * @base: base of the number (octal, hex, ...)
2206  * @precision: precision of a number
2207  * @qualifier: qualifier of a number (long, size_t, ...)
2208  */
2209 static noinline_for_stack
2210 int format_decode(const char *fmt, struct printf_spec *spec)
2211 {
2212         const char *start = fmt;
2213         char qualifier;
2214
2215         /* we finished early by reading the field width */
2216         if (spec->type == FORMAT_TYPE_WIDTH) {
2217                 if (spec->field_width < 0) {
2218                         spec->field_width = -spec->field_width;
2219                         spec->flags |= LEFT;
2220                 }
2221                 spec->type = FORMAT_TYPE_NONE;
2222                 goto precision;
2223         }
2224
2225         /* we finished early by reading the precision */
2226         if (spec->type == FORMAT_TYPE_PRECISION) {
2227                 if (spec->precision < 0)
2228                         spec->precision = 0;
2229
2230                 spec->type = FORMAT_TYPE_NONE;
2231                 goto qualifier;
2232         }
2233
2234         /* By default */
2235         spec->type = FORMAT_TYPE_NONE;
2236
2237         for (; *fmt ; ++fmt) {
2238                 if (*fmt == '%')
2239                         break;
2240         }
2241
2242         /* Return the current non-format string */
2243         if (fmt != start || !*fmt)
2244                 return fmt - start;
2245
2246         /* Process flags */
2247         spec->flags = 0;
2248
2249         while (1) { /* this also skips first '%' */
2250                 bool found = true;
2251
2252                 ++fmt;
2253
2254                 switch (*fmt) {
2255                 case '-': spec->flags |= LEFT;    break;
2256                 case '+': spec->flags |= PLUS;    break;
2257                 case ' ': spec->flags |= SPACE;   break;
2258                 case '#': spec->flags |= SPECIAL; break;
2259                 case '0': spec->flags |= ZEROPAD; break;
2260                 default:  found = false;
2261                 }
2262
2263                 if (!found)
2264                         break;
2265         }
2266
2267         /* get field width */
2268         spec->field_width = -1;
2269
2270         if (isdigit(*fmt))
2271                 spec->field_width = skip_atoi(&fmt);
2272         else if (*fmt == '*') {
2273                 /* it's the next argument */
2274                 spec->type = FORMAT_TYPE_WIDTH;
2275                 return ++fmt - start;
2276         }
2277
2278 precision:
2279         /* get the precision */
2280         spec->precision = -1;
2281         if (*fmt == '.') {
2282                 ++fmt;
2283                 if (isdigit(*fmt)) {
2284                         spec->precision = skip_atoi(&fmt);
2285                         if (spec->precision < 0)
2286                                 spec->precision = 0;
2287                 } else if (*fmt == '*') {
2288                         /* it's the next argument */
2289                         spec->type = FORMAT_TYPE_PRECISION;
2290                         return ++fmt - start;
2291                 }
2292         }
2293
2294 qualifier:
2295         /* get the conversion qualifier */
2296         qualifier = 0;
2297         if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2298             *fmt == 'z' || *fmt == 't') {
2299                 qualifier = *fmt++;
2300                 if (unlikely(qualifier == *fmt)) {
2301                         if (qualifier == 'l') {
2302                                 qualifier = 'L';
2303                                 ++fmt;
2304                         } else if (qualifier == 'h') {
2305                                 qualifier = 'H';
2306                                 ++fmt;
2307                         }
2308                 }
2309         }
2310
2311         /* default base */
2312         spec->base = 10;
2313         switch (*fmt) {
2314         case 'c':
2315                 spec->type = FORMAT_TYPE_CHAR;
2316                 return ++fmt - start;
2317
2318         case 's':
2319                 spec->type = FORMAT_TYPE_STR;
2320                 return ++fmt - start;
2321
2322         case 'p':
2323                 spec->type = FORMAT_TYPE_PTR;
2324                 return ++fmt - start;
2325
2326         case '%':
2327                 spec->type = FORMAT_TYPE_PERCENT_CHAR;
2328                 return ++fmt - start;
2329
2330         /* integer number formats - set up the flags and "break" */
2331         case 'o':
2332                 spec->base = 8;
2333                 break;
2334
2335         case 'x':
2336                 spec->flags |= SMALL;
2337                 /* fall through */
2338
2339         case 'X':
2340                 spec->base = 16;
2341                 break;
2342
2343         case 'd':
2344         case 'i':
2345                 spec->flags |= SIGN;
2346         case 'u':
2347                 break;
2348
2349         case 'n':
2350                 /*
2351                  * Since %n poses a greater security risk than
2352                  * utility, treat it as any other invalid or
2353                  * unsupported format specifier.
2354                  */
2355                 /* Fall-through */
2356
2357         default:
2358                 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2359                 spec->type = FORMAT_TYPE_INVALID;
2360                 return fmt - start;
2361         }
2362
2363         if (qualifier == 'L')
2364                 spec->type = FORMAT_TYPE_LONG_LONG;
2365         else if (qualifier == 'l') {
2366                 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2367                 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2368         } else if (qualifier == 'z') {
2369                 spec->type = FORMAT_TYPE_SIZE_T;
2370         } else if (qualifier == 't') {
2371                 spec->type = FORMAT_TYPE_PTRDIFF;
2372         } else if (qualifier == 'H') {
2373                 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2374                 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2375         } else if (qualifier == 'h') {
2376                 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2377                 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2378         } else {
2379                 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2380                 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2381         }
2382
2383         return ++fmt - start;
2384 }
2385
2386 static void
2387 set_field_width(struct printf_spec *spec, int width)
2388 {
2389         spec->field_width = width;
2390         if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2391                 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2392         }
2393 }
2394
2395 static void
2396 set_precision(struct printf_spec *spec, int prec)
2397 {
2398         spec->precision = prec;
2399         if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2400                 spec->precision = clamp(prec, 0, PRECISION_MAX);
2401         }
2402 }
2403
2404 /**
2405  * vsnprintf - Format a string and place it in a buffer
2406  * @buf: The buffer to place the result into
2407  * @size: The size of the buffer, including the trailing null space
2408  * @fmt: The format string to use
2409  * @args: Arguments for the format string
2410  *
2411  * This function generally follows C99 vsnprintf, but has some
2412  * extensions and a few limitations:
2413  *
2414  *  - ``%n`` is unsupported
2415  *  - ``%p*`` is handled by pointer()
2416  *
2417  * See pointer() or Documentation/core-api/printk-formats.rst for more
2418  * extensive description.
2419  *
2420  * **Please update the documentation in both places when making changes**
2421  *
2422  * The return value is the number of characters which would
2423  * be generated for the given input, excluding the trailing
2424  * '\0', as per ISO C99. If you want to have the exact
2425  * number of characters written into @buf as return value
2426  * (not including the trailing '\0'), use vscnprintf(). If the
2427  * return is greater than or equal to @size, the resulting
2428  * string is truncated.
2429  *
2430  * If you're not already dealing with a va_list consider using snprintf().
2431  */
2432 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2433 {
2434         unsigned long long num;
2435         char *str, *end;
2436         struct printf_spec spec = {0};
2437
2438         /* Reject out-of-range values early.  Large positive sizes are
2439            used for unknown buffer sizes. */
2440         if (WARN_ON_ONCE(size > INT_MAX))
2441                 return 0;
2442
2443         str = buf;
2444         end = buf + size;
2445
2446         /* Make sure end is always >= buf */
2447         if (end < buf) {
2448                 end = ((void *)-1);
2449                 size = end - buf;
2450         }
2451
2452         while (*fmt) {
2453                 const char *old_fmt = fmt;
2454                 int read = format_decode(fmt, &spec);
2455
2456                 fmt += read;
2457
2458                 switch (spec.type) {
2459                 case FORMAT_TYPE_NONE: {
2460                         int copy = read;
2461                         if (str < end) {
2462                                 if (copy > end - str)
2463                                         copy = end - str;
2464                                 memcpy(str, old_fmt, copy);
2465                         }
2466                         str += read;
2467                         break;
2468                 }
2469
2470                 case FORMAT_TYPE_WIDTH:
2471                         set_field_width(&spec, va_arg(args, int));
2472                         break;
2473
2474                 case FORMAT_TYPE_PRECISION:
2475                         set_precision(&spec, va_arg(args, int));
2476                         break;
2477
2478                 case FORMAT_TYPE_CHAR: {
2479                         char c;
2480
2481                         if (!(spec.flags & LEFT)) {
2482                                 while (--spec.field_width > 0) {
2483                                         if (str < end)
2484                                                 *str = ' ';
2485                                         ++str;
2486
2487                                 }
2488                         }
2489                         c = (unsigned char) va_arg(args, int);
2490                         if (str < end)
2491                                 *str = c;
2492                         ++str;
2493                         while (--spec.field_width > 0) {
2494                                 if (str < end)
2495                                         *str = ' ';
2496                                 ++str;
2497                         }
2498                         break;
2499                 }
2500
2501                 case FORMAT_TYPE_STR:
2502                         str = string(str, end, va_arg(args, char *), spec);
2503                         break;
2504
2505                 case FORMAT_TYPE_PTR:
2506                         str = pointer(fmt, str, end, va_arg(args, void *),
2507                                       spec);
2508                         while (isalnum(*fmt))
2509                                 fmt++;
2510                         break;
2511
2512                 case FORMAT_TYPE_PERCENT_CHAR:
2513                         if (str < end)
2514                                 *str = '%';
2515                         ++str;
2516                         break;
2517
2518                 case FORMAT_TYPE_INVALID:
2519                         /*
2520                          * Presumably the arguments passed gcc's type
2521                          * checking, but there is no safe or sane way
2522                          * for us to continue parsing the format and
2523                          * fetching from the va_list; the remaining
2524                          * specifiers and arguments would be out of
2525                          * sync.
2526                          */
2527                         goto out;
2528
2529                 default:
2530                         switch (spec.type) {
2531                         case FORMAT_TYPE_LONG_LONG:
2532                                 num = va_arg(args, long long);
2533                                 break;
2534                         case FORMAT_TYPE_ULONG:
2535                                 num = va_arg(args, unsigned long);
2536                                 break;
2537                         case FORMAT_TYPE_LONG:
2538                                 num = va_arg(args, long);
2539                                 break;
2540                         case FORMAT_TYPE_SIZE_T:
2541                                 if (spec.flags & SIGN)
2542                                         num = va_arg(args, ssize_t);
2543                                 else
2544                                         num = va_arg(args, size_t);
2545                                 break;
2546                         case FORMAT_TYPE_PTRDIFF:
2547                                 num = va_arg(args, ptrdiff_t);
2548                                 break;
2549                         case FORMAT_TYPE_UBYTE:
2550                                 num = (unsigned char) va_arg(args, int);
2551                                 break;
2552                         case FORMAT_TYPE_BYTE:
2553                                 num = (signed char) va_arg(args, int);
2554                                 break;
2555                         case FORMAT_TYPE_USHORT:
2556                                 num = (unsigned short) va_arg(args, int);
2557                                 break;
2558                         case FORMAT_TYPE_SHORT:
2559                                 num = (short) va_arg(args, int);
2560                                 break;
2561                         case FORMAT_TYPE_INT:
2562                                 num = (int) va_arg(args, int);
2563                                 break;
2564                         default:
2565                                 num = va_arg(args, unsigned int);
2566                         }
2567
2568                         str = number(str, end, num, spec);
2569                 }
2570         }
2571
2572 out:
2573         if (size > 0) {
2574                 if (str < end)
2575                         *str = '\0';
2576                 else
2577                         end[-1] = '\0';
2578         }
2579
2580         /* the trailing null byte doesn't count towards the total */
2581         return str-buf;
2582
2583 }
2584 EXPORT_SYMBOL(vsnprintf);
2585
2586 /**
2587  * vscnprintf - Format a string and place it in a buffer
2588  * @buf: The buffer to place the result into
2589  * @size: The size of the buffer, including the trailing null space
2590  * @fmt: The format string to use
2591  * @args: Arguments for the format string
2592  *
2593  * The return value is the number of characters which have been written into
2594  * the @buf not including the trailing '\0'. If @size is == 0 the function
2595  * returns 0.
2596  *
2597  * If you're not already dealing with a va_list consider using scnprintf().
2598  *
2599  * See the vsnprintf() documentation for format string extensions over C99.
2600  */
2601 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2602 {
2603         int i;
2604
2605         i = vsnprintf(buf, size, fmt, args);
2606
2607         if (likely(i < size))
2608                 return i;
2609         if (size != 0)
2610                 return size - 1;
2611         return 0;
2612 }
2613 EXPORT_SYMBOL(vscnprintf);
2614
2615 /**
2616  * snprintf - Format a string and place it in a buffer
2617  * @buf: The buffer to place the result into
2618  * @size: The size of the buffer, including the trailing null space
2619  * @fmt: The format string to use
2620  * @...: Arguments for the format string
2621  *
2622  * The return value is the number of characters which would be
2623  * generated for the given input, excluding the trailing null,
2624  * as per ISO C99.  If the return is greater than or equal to
2625  * @size, the resulting string is truncated.
2626  *
2627  * See the vsnprintf() documentation for format string extensions over C99.
2628  */
2629 int snprintf(char *buf, size_t size, const char *fmt, ...)
2630 {
2631         va_list args;
2632         int i;
2633
2634         va_start(args, fmt);
2635         i = vsnprintf(buf, size, fmt, args);
2636         va_end(args);
2637
2638         return i;
2639 }
2640 EXPORT_SYMBOL(snprintf);
2641
2642 /**
2643  * scnprintf - Format a string and place it in a buffer
2644  * @buf: The buffer to place the result into
2645  * @size: The size of the buffer, including the trailing null space
2646  * @fmt: The format string to use
2647  * @...: Arguments for the format string
2648  *
2649  * The return value is the number of characters written into @buf not including
2650  * the trailing '\0'. If @size is == 0 the function returns 0.
2651  */
2652
2653 int scnprintf(char *buf, size_t size, const char *fmt, ...)
2654 {
2655         va_list args;
2656         int i;
2657
2658         va_start(args, fmt);
2659         i = vscnprintf(buf, size, fmt, args);
2660         va_end(args);
2661
2662         return i;
2663 }
2664 EXPORT_SYMBOL(scnprintf);
2665
2666 /**
2667  * vsprintf - Format a string and place it in a buffer
2668  * @buf: The buffer to place the result into
2669  * @fmt: The format string to use
2670  * @args: Arguments for the format string
2671  *
2672  * The function returns the number of characters written
2673  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2674  * buffer overflows.
2675  *
2676  * If you're not already dealing with a va_list consider using sprintf().
2677  *
2678  * See the vsnprintf() documentation for format string extensions over C99.
2679  */
2680 int vsprintf(char *buf, const char *fmt, va_list args)
2681 {
2682         return vsnprintf(buf, INT_MAX, fmt, args);
2683 }
2684 EXPORT_SYMBOL(vsprintf);
2685
2686 /**
2687  * sprintf - Format a string and place it in a buffer
2688  * @buf: The buffer to place the result into
2689  * @fmt: The format string to use
2690  * @...: Arguments for the format string
2691  *
2692  * The function returns the number of characters written
2693  * into @buf. Use snprintf() or scnprintf() in order to avoid
2694  * buffer overflows.
2695  *
2696  * See the vsnprintf() documentation for format string extensions over C99.
2697  */
2698 int sprintf(char *buf, const char *fmt, ...)
2699 {
2700         va_list args;
2701         int i;
2702
2703         va_start(args, fmt);
2704         i = vsnprintf(buf, INT_MAX, fmt, args);
2705         va_end(args);
2706
2707         return i;
2708 }
2709 EXPORT_SYMBOL(sprintf);
2710
2711 #ifdef CONFIG_BINARY_PRINTF
2712 /*
2713  * bprintf service:
2714  * vbin_printf() - VA arguments to binary data
2715  * bstr_printf() - Binary data to text string
2716  */
2717
2718 /**
2719  * vbin_printf - Parse a format string and place args' binary value in a buffer
2720  * @bin_buf: The buffer to place args' binary value
2721  * @size: The size of the buffer(by words(32bits), not characters)
2722  * @fmt: The format string to use
2723  * @args: Arguments for the format string
2724  *
2725  * The format follows C99 vsnprintf, except %n is ignored, and its argument
2726  * is skipped.
2727  *
2728  * The return value is the number of words(32bits) which would be generated for
2729  * the given input.
2730  *
2731  * NOTE:
2732  * If the return value is greater than @size, the resulting bin_buf is NOT
2733  * valid for bstr_printf().
2734  */
2735 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2736 {
2737         struct printf_spec spec = {0};
2738         char *str, *end;
2739         int width;
2740
2741         str = (char *)bin_buf;
2742         end = (char *)(bin_buf + size);
2743
2744 #define save_arg(type)                                                  \
2745 ({                                                                      \
2746         unsigned long long value;                                       \
2747         if (sizeof(type) == 8) {                                        \
2748                 unsigned long long val8;                                \
2749                 str = PTR_ALIGN(str, sizeof(u32));                      \
2750                 val8 = va_arg(args, unsigned long long);                \
2751                 if (str + sizeof(type) <= end) {                        \
2752                         *(u32 *)str = *(u32 *)&val8;                    \
2753                         *(u32 *)(str + 4) = *((u32 *)&val8 + 1);        \
2754                 }                                                       \
2755                 value = val8;                                           \
2756         } else {                                                        \
2757                 unsigned int val4;                                      \
2758                 str = PTR_ALIGN(str, sizeof(type));                     \
2759                 val4 = va_arg(args, int);                               \
2760                 if (str + sizeof(type) <= end)                          \
2761                         *(typeof(type) *)str = (type)(long)val4;        \
2762                 value = (unsigned long long)val4;                       \
2763         }                                                               \
2764         str += sizeof(type);                                            \
2765         value;                                                          \
2766 })
2767
2768         while (*fmt) {
2769                 int read = format_decode(fmt, &spec);
2770
2771                 fmt += read;
2772
2773                 switch (spec.type) {
2774                 case FORMAT_TYPE_NONE:
2775                 case FORMAT_TYPE_PERCENT_CHAR:
2776                         break;
2777                 case FORMAT_TYPE_INVALID:
2778                         goto out;
2779
2780                 case FORMAT_TYPE_WIDTH:
2781                 case FORMAT_TYPE_PRECISION:
2782                         width = (int)save_arg(int);
2783                         /* Pointers may require the width */
2784                         if (*fmt == 'p')
2785                                 set_field_width(&spec, width);
2786                         break;
2787
2788                 case FORMAT_TYPE_CHAR:
2789                         save_arg(char);
2790                         break;
2791
2792                 case FORMAT_TYPE_STR: {
2793                         const char *save_str = va_arg(args, char *);
2794                         const char *err_msg;
2795                         size_t len;
2796
2797                         err_msg = check_pointer_msg(save_str);
2798                         if (err_msg)
2799                                 save_str = err_msg;
2800
2801                         len = strlen(save_str) + 1;
2802                         if (str + len < end)
2803                                 memcpy(str, save_str, len);
2804                         str += len;
2805                         break;
2806                 }
2807
2808                 case FORMAT_TYPE_PTR:
2809                         /* Dereferenced pointers must be done now */
2810                         switch (*fmt) {
2811                         /* Dereference of functions is still OK */
2812                         case 'S':
2813                         case 's':
2814                         case 'F':
2815                         case 'f':
2816                         case 'x':
2817                         case 'K':
2818                                 save_arg(void *);
2819                                 break;
2820                         default:
2821                                 if (!isalnum(*fmt)) {
2822                                         save_arg(void *);
2823                                         break;
2824                                 }
2825                                 str = pointer(fmt, str, end, va_arg(args, void *),
2826                                               spec);
2827                                 if (str + 1 < end)
2828                                         *str++ = '\0';
2829                                 else
2830                                         end[-1] = '\0'; /* Must be nul terminated */
2831                         }
2832                         /* skip all alphanumeric pointer suffixes */
2833                         while (isalnum(*fmt))
2834                                 fmt++;
2835                         break;
2836
2837                 default:
2838                         switch (spec.type) {
2839
2840                         case FORMAT_TYPE_LONG_LONG:
2841                                 save_arg(long long);
2842                                 break;
2843                         case FORMAT_TYPE_ULONG:
2844                         case FORMAT_TYPE_LONG:
2845                                 save_arg(unsigned long);
2846                                 break;
2847                         case FORMAT_TYPE_SIZE_T:
2848                                 save_arg(size_t);
2849                                 break;
2850                         case FORMAT_TYPE_PTRDIFF:
2851                                 save_arg(ptrdiff_t);
2852                                 break;
2853                         case FORMAT_TYPE_UBYTE:
2854                         case FORMAT_TYPE_BYTE:
2855                                 save_arg(char);
2856                                 break;
2857                         case FORMAT_TYPE_USHORT:
2858                         case FORMAT_TYPE_SHORT:
2859                                 save_arg(short);
2860                                 break;
2861                         default:
2862                                 save_arg(int);
2863                         }
2864                 }
2865         }
2866
2867 out:
2868         return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2869 #undef save_arg
2870 }
2871 EXPORT_SYMBOL_GPL(vbin_printf);
2872
2873 /**
2874  * bstr_printf - Format a string from binary arguments and place it in a buffer
2875  * @buf: The buffer to place the result into
2876  * @size: The size of the buffer, including the trailing null space
2877  * @fmt: The format string to use
2878  * @bin_buf: Binary arguments for the format string
2879  *
2880  * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2881  * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2882  * a binary buffer that generated by vbin_printf.
2883  *
2884  * The format follows C99 vsnprintf, but has some extensions:
2885  *  see vsnprintf comment for details.
2886  *
2887  * The return value is the number of characters which would
2888  * be generated for the given input, excluding the trailing
2889  * '\0', as per ISO C99. If you want to have the exact
2890  * number of characters written into @buf as return value
2891  * (not including the trailing '\0'), use vscnprintf(). If the
2892  * return is greater than or equal to @size, the resulting
2893  * string is truncated.
2894  */
2895 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2896 {
2897         struct printf_spec spec = {0};
2898         char *str, *end;
2899         const char *args = (const char *)bin_buf;
2900
2901         if (WARN_ON_ONCE(size > INT_MAX))
2902                 return 0;
2903
2904         str = buf;
2905         end = buf + size;
2906
2907 #define get_arg(type)                                                   \
2908 ({                                                                      \
2909         typeof(type) value;                                             \
2910         if (sizeof(type) == 8) {                                        \
2911                 args = PTR_ALIGN(args, sizeof(u32));                    \
2912                 *(u32 *)&value = *(u32 *)args;                          \
2913                 *((u32 *)&value + 1) = *(u32 *)(args + 4);              \
2914         } else {                                                        \
2915                 args = PTR_ALIGN(args, sizeof(type));                   \
2916                 value = *(typeof(type) *)args;                          \
2917         }                                                               \
2918         args += sizeof(type);                                           \
2919         value;                                                          \
2920 })
2921
2922         /* Make sure end is always >= buf */
2923         if (end < buf) {
2924                 end = ((void *)-1);
2925                 size = end - buf;
2926         }
2927
2928         while (*fmt) {
2929                 const char *old_fmt = fmt;
2930                 int read = format_decode(fmt, &spec);
2931
2932                 fmt += read;
2933
2934                 switch (spec.type) {
2935                 case FORMAT_TYPE_NONE: {
2936                         int copy = read;
2937                         if (str < end) {
2938                                 if (copy > end - str)
2939                                         copy = end - str;
2940                                 memcpy(str, old_fmt, copy);
2941                         }
2942                         str += read;
2943                         break;
2944                 }
2945
2946                 case FORMAT_TYPE_WIDTH:
2947                         set_field_width(&spec, get_arg(int));
2948                         break;
2949
2950                 case FORMAT_TYPE_PRECISION:
2951                         set_precision(&spec, get_arg(int));
2952                         break;
2953
2954                 case FORMAT_TYPE_CHAR: {
2955                         char c;
2956
2957                         if (!(spec.flags & LEFT)) {
2958                                 while (--spec.field_width > 0) {
2959                                         if (str < end)
2960                                                 *str = ' ';
2961                                         ++str;
2962                                 }
2963                         }
2964                         c = (unsigned char) get_arg(char);
2965                         if (str < end)
2966                                 *str = c;
2967                         ++str;
2968                         while (--spec.field_width > 0) {
2969                                 if (str < end)
2970                                         *str = ' ';
2971                                 ++str;
2972                         }
2973                         break;
2974                 }
2975
2976                 case FORMAT_TYPE_STR: {
2977                         const char *str_arg = args;
2978                         args += strlen(str_arg) + 1;
2979                         str = string(str, end, (char *)str_arg, spec);
2980                         break;
2981                 }
2982
2983                 case FORMAT_TYPE_PTR: {
2984                         bool process = false;
2985                         int copy, len;
2986                         /* Non function dereferences were already done */
2987                         switch (*fmt) {
2988                         case 'S':
2989                         case 's':
2990                         case 'F':
2991                         case 'f':
2992                         case 'x':
2993                         case 'K':
2994                                 process = true;
2995                                 break;
2996                         default:
2997                                 if (!isalnum(*fmt)) {
2998                                         process = true;
2999                                         break;
3000                                 }
3001                                 /* Pointer dereference was already processed */
3002                                 if (str < end) {
3003                                         len = copy = strlen(args);
3004                                         if (copy > end - str)
3005                                                 copy = end - str;
3006                                         memcpy(str, args, copy);
3007                                         str += len;
3008                                         args += len + 1;
3009                                 }
3010                         }
3011                         if (process)
3012                                 str = pointer(fmt, str, end, get_arg(void *), spec);
3013
3014                         while (isalnum(*fmt))
3015                                 fmt++;
3016                         break;
3017                 }
3018
3019                 case FORMAT_TYPE_PERCENT_CHAR:
3020                         if (str < end)
3021                                 *str = '%';
3022                         ++str;
3023                         break;
3024
3025                 case FORMAT_TYPE_INVALID:
3026                         goto out;
3027
3028                 default: {
3029                         unsigned long long num;
3030
3031                         switch (spec.type) {
3032
3033                         case FORMAT_TYPE_LONG_LONG:
3034                                 num = get_arg(long long);
3035                                 break;
3036                         case FORMAT_TYPE_ULONG:
3037                         case FORMAT_TYPE_LONG:
3038                                 num = get_arg(unsigned long);
3039                                 break;
3040                         case FORMAT_TYPE_SIZE_T:
3041                                 num = get_arg(size_t);
3042                                 break;
3043                         case FORMAT_TYPE_PTRDIFF:
3044                                 num = get_arg(ptrdiff_t);
3045                                 break;
3046                         case FORMAT_TYPE_UBYTE:
3047                                 num = get_arg(unsigned char);
3048                                 break;
3049                         case FORMAT_TYPE_BYTE:
3050                                 num = get_arg(signed char);
3051                                 break;
3052                         case FORMAT_TYPE_USHORT:
3053                                 num = get_arg(unsigned short);
3054                                 break;
3055                         case FORMAT_TYPE_SHORT:
3056                                 num = get_arg(short);
3057                                 break;
3058                         case FORMAT_TYPE_UINT:
3059                                 num = get_arg(unsigned int);
3060                                 break;
3061                         default:
3062                                 num = get_arg(int);
3063                         }
3064
3065                         str = number(str, end, num, spec);
3066                 } /* default: */
3067                 } /* switch(spec.type) */
3068         } /* while(*fmt) */
3069
3070 out:
3071         if (size > 0) {
3072                 if (str < end)
3073                         *str = '\0';
3074                 else
3075                         end[-1] = '\0';
3076         }
3077
3078 #undef get_arg
3079
3080         /* the trailing null byte doesn't count towards the total */
3081         return str - buf;
3082 }
3083 EXPORT_SYMBOL_GPL(bstr_printf);
3084
3085 /**
3086  * bprintf - Parse a format string and place args' binary value in a buffer
3087  * @bin_buf: The buffer to place args' binary value
3088  * @size: The size of the buffer(by words(32bits), not characters)
3089  * @fmt: The format string to use
3090  * @...: Arguments for the format string
3091  *
3092  * The function returns the number of words(u32) written
3093  * into @bin_buf.
3094  */
3095 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
3096 {
3097         va_list args;
3098         int ret;
3099
3100         va_start(args, fmt);
3101         ret = vbin_printf(bin_buf, size, fmt, args);
3102         va_end(args);
3103
3104         return ret;
3105 }
3106 EXPORT_SYMBOL_GPL(bprintf);
3107
3108 #endif /* CONFIG_BINARY_PRINTF */
3109
3110 /**
3111  * vsscanf - Unformat a buffer into a list of arguments
3112  * @buf:        input buffer
3113  * @fmt:        format of buffer
3114  * @args:       arguments
3115  */
3116 int vsscanf(const char *buf, const char *fmt, va_list args)
3117 {
3118         const char *str = buf;
3119         char *next;
3120         char digit;
3121         int num = 0;
3122         u8 qualifier;
3123         unsigned int base;
3124         union {
3125                 long long s;
3126                 unsigned long long u;
3127         } val;
3128         s16 field_width;
3129         bool is_sign;
3130
3131         while (*fmt) {
3132                 /* skip any white space in format */
3133                 /* white space in format matchs any amount of
3134                  * white space, including none, in the input.
3135                  */
3136                 if (isspace(*fmt)) {
3137                         fmt = skip_spaces(++fmt);
3138                         str = skip_spaces(str);
3139                 }
3140
3141                 /* anything that is not a conversion must match exactly */
3142                 if (*fmt != '%' && *fmt) {
3143                         if (*fmt++ != *str++)
3144                                 break;
3145                         continue;
3146                 }
3147
3148                 if (!*fmt)
3149                         break;
3150                 ++fmt;
3151
3152                 /* skip this conversion.
3153                  * advance both strings to next white space
3154                  */
3155                 if (*fmt == '*') {
3156                         if (!*str)
3157                                 break;
3158                         while (!isspace(*fmt) && *fmt != '%' && *fmt) {
3159                                 /* '%*[' not yet supported, invalid format */
3160                                 if (*fmt == '[')
3161                                         return num;
3162                                 fmt++;
3163                         }
3164                         while (!isspace(*str) && *str)
3165                                 str++;
3166                         continue;
3167                 }
3168
3169                 /* get field width */
3170                 field_width = -1;
3171                 if (isdigit(*fmt)) {
3172                         field_width = skip_atoi(&fmt);
3173                         if (field_width <= 0)
3174                                 break;
3175                 }
3176
3177                 /* get conversion qualifier */
3178                 qualifier = -1;
3179                 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
3180                     *fmt == 'z') {
3181                         qualifier = *fmt++;
3182                         if (unlikely(qualifier == *fmt)) {
3183                                 if (qualifier == 'h') {
3184                                         qualifier = 'H';
3185                                         fmt++;
3186                                 } else if (qualifier == 'l') {
3187                                         qualifier = 'L';
3188                                         fmt++;
3189                                 }
3190                         }
3191                 }
3192
3193                 if (!*fmt)
3194                         break;
3195
3196                 if (*fmt == 'n') {
3197                         /* return number of characters read so far */
3198                         *va_arg(args, int *) = str - buf;
3199                         ++fmt;
3200                         continue;
3201                 }
3202
3203                 if (!*str)
3204                         break;
3205
3206                 base = 10;
3207                 is_sign = false;
3208
3209                 switch (*fmt++) {
3210                 case 'c':
3211                 {
3212                         char *s = (char *)va_arg(args, char*);
3213                         if (field_width == -1)
3214                                 field_width = 1;
3215                         do {
3216                                 *s++ = *str++;
3217                         } while (--field_width > 0 && *str);
3218                         num++;
3219                 }
3220                 continue;
3221                 case 's':
3222                 {
3223                         char *s = (char *)va_arg(args, char *);
3224                         if (field_width == -1)
3225                                 field_width = SHRT_MAX;
3226                         /* first, skip leading white space in buffer */
3227                         str = skip_spaces(str);
3228
3229                         /* now copy until next white space */
3230                         while (*str && !isspace(*str) && field_width--)
3231                                 *s++ = *str++;
3232                         *s = '\0';
3233                         num++;
3234                 }
3235                 continue;
3236                 /*
3237                  * Warning: This implementation of the '[' conversion specifier
3238                  * deviates from its glibc counterpart in the following ways:
3239                  * (1) It does NOT support ranges i.e. '-' is NOT a special
3240                  *     character
3241                  * (2) It cannot match the closing bracket ']' itself
3242                  * (3) A field width is required
3243                  * (4) '%*[' (discard matching input) is currently not supported
3244                  *
3245                  * Example usage:
3246                  * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3247                  *              buf1, buf2, buf3);
3248                  * if (ret < 3)
3249                  *    // etc..
3250                  */
3251                 case '[':
3252                 {
3253                         char *s = (char *)va_arg(args, char *);
3254                         DECLARE_BITMAP(set, 256) = {0};
3255                         unsigned int len = 0;
3256                         bool negate = (*fmt == '^');
3257
3258                         /* field width is required */
3259                         if (field_width == -1)
3260                                 return num;
3261
3262                         if (negate)
3263                                 ++fmt;
3264
3265                         for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3266                                 set_bit((u8)*fmt, set);
3267
3268                         /* no ']' or no character set found */
3269                         if (!*fmt || !len)
3270                                 return num;
3271                         ++fmt;
3272
3273                         if (negate) {
3274                                 bitmap_complement(set, set, 256);
3275                                 /* exclude null '\0' byte */
3276                                 clear_bit(0, set);
3277                         }
3278
3279                         /* match must be non-empty */
3280                         if (!test_bit((u8)*str, set))
3281                                 return num;
3282
3283                         while (test_bit((u8)*str, set) && field_width--)
3284                                 *s++ = *str++;
3285                         *s = '\0';
3286                         ++num;
3287                 }
3288                 continue;
3289                 case 'o':
3290                         base = 8;
3291                         break;
3292                 case 'x':
3293                 case 'X':
3294                         base = 16;
3295                         break;
3296                 case 'i':
3297                         base = 0;
3298                         /* fall through */
3299                 case 'd':
3300                         is_sign = true;
3301                         /* fall through */
3302                 case 'u':
3303                         break;
3304                 case '%':
3305                         /* looking for '%' in str */
3306                         if (*str++ != '%')
3307                                 return num;
3308                         continue;
3309                 default:
3310                         /* invalid format; stop here */
3311                         return num;
3312                 }
3313
3314                 /* have some sort of integer conversion.
3315                  * first, skip white space in buffer.
3316                  */
3317                 str = skip_spaces(str);
3318
3319                 digit = *str;
3320                 if (is_sign && digit == '-')
3321                         digit = *(str + 1);
3322
3323                 if (!digit
3324                     || (base == 16 && !isxdigit(digit))
3325                     || (base == 10 && !isdigit(digit))
3326                     || (base == 8 && (!isdigit(digit) || digit > '7'))
3327                     || (base == 0 && !isdigit(digit)))
3328                         break;
3329
3330                 if (is_sign)
3331                         val.s = qualifier != 'L' ?
3332                                 simple_strtol(str, &next, base) :
3333                                 simple_strtoll(str, &next, base);
3334                 else
3335                         val.u = qualifier != 'L' ?
3336                                 simple_strtoul(str, &next, base) :
3337                                 simple_strtoull(str, &next, base);
3338
3339                 if (field_width > 0 && next - str > field_width) {
3340                         if (base == 0)
3341                                 _parse_integer_fixup_radix(str, &base);
3342                         while (next - str > field_width) {
3343                                 if (is_sign)
3344                                         val.s = div_s64(val.s, base);
3345                                 else
3346                                         val.u = div_u64(val.u, base);
3347                                 --next;
3348                         }
3349                 }
3350
3351                 switch (qualifier) {
3352                 case 'H':       /* that's 'hh' in format */
3353                         if (is_sign)
3354                                 *va_arg(args, signed char *) = val.s;
3355                         else
3356                                 *va_arg(args, unsigned char *) = val.u;
3357                         break;
3358                 case 'h':
3359                         if (is_sign)
3360                                 *va_arg(args, short *) = val.s;
3361                         else
3362                                 *va_arg(args, unsigned short *) = val.u;
3363                         break;
3364                 case 'l':
3365                         if (is_sign)
3366                                 *va_arg(args, long *) = val.s;
3367                         else
3368                                 *va_arg(args, unsigned long *) = val.u;
3369                         break;
3370                 case 'L':
3371                         if (is_sign)
3372                                 *va_arg(args, long long *) = val.s;
3373                         else
3374                                 *va_arg(args, unsigned long long *) = val.u;
3375                         break;
3376                 case 'z':
3377                         *va_arg(args, size_t *) = val.u;
3378                         break;
3379                 default:
3380                         if (is_sign)
3381                                 *va_arg(args, int *) = val.s;
3382                         else
3383                                 *va_arg(args, unsigned int *) = val.u;
3384                         break;
3385                 }
3386                 num++;
3387
3388                 if (!next)
3389                         break;
3390                 str = next;
3391         }
3392
3393         return num;
3394 }
3395 EXPORT_SYMBOL(vsscanf);
3396
3397 /**
3398  * sscanf - Unformat a buffer into a list of arguments
3399  * @buf:        input buffer
3400  * @fmt:        formatting of buffer
3401  * @...:        resulting arguments
3402  */
3403 int sscanf(const char *buf, const char *fmt, ...)
3404 {
3405         va_list args;
3406         int i;
3407
3408         va_start(args, fmt);
3409         i = vsscanf(buf, fmt, args);
3410         va_end(args);
3411
3412         return i;
3413 }
3414 EXPORT_SYMBOL(sscanf);