lib/vsprintf.c

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  56  * This function is obsolete.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