linux/lib/vsprintf.c
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   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  56 * This function is obsolete.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 */
  58unsigned 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}
  73EXPORT_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 */
  83unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
  84{
  85        return simple_strtoull(cp, endp, base);
  86}
  87EXPORT_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 */
  97long 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}
 104EXPORT_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 */
 114long 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}
 121EXPORT_SYMBOL(simple_strtoll);
 122
 123static noinline_for_stack
 124int 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
 160static 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*/
 181static noinline_for_stack
 182char *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;
 212out_q:
 213        /* 1 <= q < 100 */
 214        r = q;
 215out_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
 223static noinline_for_stack
 224char *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
 249static noinline_for_stack
 250char *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
 263static void
 264put_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 */
 283static noinline_for_stack
 284unsigned 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 */
 297static
 298char *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 */
 339int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
 340{
 341        /* put_dec requires 2-byte alignment of the buffer. */
 342        char tmp[sizeof(num) * 3] __aligned(2);
 343        int idx, len;
 344
 345        /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
 346        if (num <= 9) {
 347                tmp[0] = '0' + num;
 348                len = 1;
 349        } else {
 350                len = put_dec(tmp, num) - tmp;
 351        }
 352
 353        if (len > size || width > size)
 354                return 0;
 355
 356        if (width > len) {
 357                width = width - len;
 358                for (idx = 0; idx < width; idx++)
 359                        buf[idx] = ' ';
 360        } else {
 361                width = 0;
 362        }
 363
 364        for (idx = 0; idx < len; ++idx)
 365                buf[idx + width] = tmp[len - idx - 1];
 366
 367        return len + width;
 368}
 369
 370#define SIGN    1               /* unsigned/signed, must be 1 */
 371#define LEFT    2               /* left justified */
 372#define PLUS    4               /* show plus */
 373#define SPACE   8               /* space if plus */
 374#define ZEROPAD 16              /* pad with zero, must be 16 == '0' - ' ' */
 375#define SMALL   32              /* use lowercase in hex (must be 32 == 0x20) */
 376#define SPECIAL 64              /* prefix hex with "0x", octal with "0" */
 377
 378enum format_type {
 379        FORMAT_TYPE_NONE, /* Just a string part */
 380        FORMAT_TYPE_WIDTH,
 381        FORMAT_TYPE_PRECISION,
 382        FORMAT_TYPE_CHAR,
 383        FORMAT_TYPE_STR,
 384        FORMAT_TYPE_PTR,
 385        FORMAT_TYPE_PERCENT_CHAR,
 386        FORMAT_TYPE_INVALID,
 387        FORMAT_TYPE_LONG_LONG,
 388        FORMAT_TYPE_ULONG,
 389        FORMAT_TYPE_LONG,
 390        FORMAT_TYPE_UBYTE,
 391        FORMAT_TYPE_BYTE,
 392        FORMAT_TYPE_USHORT,
 393        FORMAT_TYPE_SHORT,
 394        FORMAT_TYPE_UINT,
 395        FORMAT_TYPE_INT,
 396        FORMAT_TYPE_SIZE_T,
 397        FORMAT_TYPE_PTRDIFF
 398};
 399
 400struct printf_spec {
 401        unsigned int    type:8;         /* format_type enum */
 402        signed int      field_width:24; /* width of output field */
 403        unsigned int    flags:8;        /* flags to number() */
 404        unsigned int    base:8;         /* number base, 8, 10 or 16 only */
 405        signed int      precision:16;   /* # of digits/chars */
 406} __packed;
 407#define FIELD_WIDTH_MAX ((1 << 23) - 1)
 408#define PRECISION_MAX ((1 << 15) - 1)
 409
 410static noinline_for_stack
 411char *number(char *buf, char *end, unsigned long long num,
 412             struct printf_spec spec)
 413{
 414        /* put_dec requires 2-byte alignment of the buffer. */
 415        char tmp[3 * sizeof(num)] __aligned(2);
 416        char sign;
 417        char locase;
 418        int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
 419        int i;
 420        bool is_zero = num == 0LL;
 421        int field_width = spec.field_width;
 422        int precision = spec.precision;
 423
 424        BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
 425
 426        /* locase = 0 or 0x20. ORing digits or letters with 'locase'
 427         * produces same digits or (maybe lowercased) letters */
 428        locase = (spec.flags & SMALL);
 429        if (spec.flags & LEFT)
 430                spec.flags &= ~ZEROPAD;
 431        sign = 0;
 432        if (spec.flags & SIGN) {
 433                if ((signed long long)num < 0) {
 434                        sign = '-';
 435                        num = -(signed long long)num;
 436                        field_width--;
 437                } else if (spec.flags & PLUS) {
 438                        sign = '+';
 439                        field_width--;
 440                } else if (spec.flags & SPACE) {
 441                        sign = ' ';
 442                        field_width--;
 443                }
 444        }
 445        if (need_pfx) {
 446                if (spec.base == 16)
 447                        field_width -= 2;
 448                else if (!is_zero)
 449                        field_width--;
 450        }
 451
 452        /* generate full string in tmp[], in reverse order */
 453        i = 0;
 454        if (num < spec.base)
 455                tmp[i++] = hex_asc_upper[num] | locase;
 456        else if (spec.base != 10) { /* 8 or 16 */
 457                int mask = spec.base - 1;
 458                int shift = 3;
 459
 460                if (spec.base == 16)
 461                        shift = 4;
 462                do {
 463                        tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
 464                        num >>= shift;
 465                } while (num);
 466        } else { /* base 10 */
 467                i = put_dec(tmp, num) - tmp;
 468        }
 469
 470        /* printing 100 using %2d gives "100", not "00" */
 471        if (i > precision)
 472                precision = i;
 473        /* leading space padding */
 474        field_width -= precision;
 475        if (!(spec.flags & (ZEROPAD | LEFT))) {
 476                while (--field_width >= 0) {
 477                        if (buf < end)
 478                                *buf = ' ';
 479                        ++buf;
 480                }
 481        }
 482        /* sign */
 483        if (sign) {
 484                if (buf < end)
 485                        *buf = sign;
 486                ++buf;
 487        }
 488        /* "0x" / "0" prefix */
 489        if (need_pfx) {
 490                if (spec.base == 16 || !is_zero) {
 491                        if (buf < end)
 492                                *buf = '0';
 493                        ++buf;
 494                }
 495                if (spec.base == 16) {
 496                        if (buf < end)
 497                                *buf = ('X' | locase);
 498                        ++buf;
 499                }
 500        }
 501        /* zero or space padding */
 502        if (!(spec.flags & LEFT)) {
 503                char c = ' ' + (spec.flags & ZEROPAD);
 504                BUILD_BUG_ON(' ' + ZEROPAD != '0');
 505                while (--field_width >= 0) {
 506                        if (buf < end)
 507                                *buf = c;
 508                        ++buf;
 509                }
 510        }
 511        /* hmm even more zero padding? */
 512        while (i <= --precision) {
 513                if (buf < end)
 514                        *buf = '0';
 515                ++buf;
 516        }
 517        /* actual digits of result */
 518        while (--i >= 0) {
 519                if (buf < end)
 520                        *buf = tmp[i];
 521                ++buf;
 522        }
 523        /* trailing space padding */
 524        while (--field_width >= 0) {
 525                if (buf < end)
 526                        *buf = ' ';
 527                ++buf;
 528        }
 529
 530        return buf;
 531}
 532
 533static noinline_for_stack
 534char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
 535{
 536        struct printf_spec spec;
 537
 538        spec.type = FORMAT_TYPE_PTR;
 539        spec.field_width = 2 + 2 * size;        /* 0x + hex */
 540        spec.flags = SPECIAL | SMALL | ZEROPAD;
 541        spec.base = 16;
 542        spec.precision = -1;
 543
 544        return number(buf, end, num, spec);
 545}
 546
 547static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
 548{
 549        size_t size;
 550        if (buf >= end) /* nowhere to put anything */
 551                return;
 552        size = end - buf;
 553        if (size <= spaces) {
 554                memset(buf, ' ', size);
 555                return;
 556        }
 557        if (len) {
 558                if (len > size - spaces)
 559                        len = size - spaces;
 560                memmove(buf + spaces, buf, len);
 561        }
 562        memset(buf, ' ', spaces);
 563}
 564
 565/*
 566 * Handle field width padding for a string.
 567 * @buf: current buffer position
 568 * @n: length of string
 569 * @end: end of output buffer
 570 * @spec: for field width and flags
 571 * Returns: new buffer position after padding.
 572 */
 573static noinline_for_stack
 574char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
 575{
 576        unsigned spaces;
 577
 578        if (likely(n >= spec.field_width))
 579                return buf;
 580        /* we want to pad the sucker */
 581        spaces = spec.field_width - n;
 582        if (!(spec.flags & LEFT)) {
 583                move_right(buf - n, end, n, spaces);
 584                return buf + spaces;
 585        }
 586        while (spaces--) {
 587                if (buf < end)
 588                        *buf = ' ';
 589                ++buf;
 590        }
 591        return buf;
 592}
 593
 594static noinline_for_stack
 595char *string(char *buf, char *end, const char *s, struct printf_spec spec)
 596{
 597        int len = 0;
 598        size_t lim = spec.precision;
 599
 600        if ((unsigned long)s < PAGE_SIZE)
 601                s = "(null)";
 602
 603        while (lim--) {
 604                char c = *s++;
 605                if (!c)
 606                        break;
 607                if (buf < end)
 608                        *buf = c;
 609                ++buf;
 610                ++len;
 611        }
 612        return widen_string(buf, len, end, spec);
 613}
 614
 615static noinline_for_stack
 616char *pointer_string(char *buf, char *end, const void *ptr,
 617                     struct printf_spec spec)
 618{
 619        spec.base = 16;
 620        spec.flags |= SMALL;
 621        if (spec.field_width == -1) {
 622                spec.field_width = 2 * sizeof(ptr);
 623                spec.flags |= ZEROPAD;
 624        }
 625
 626        return number(buf, end, (unsigned long int)ptr, spec);
 627}
 628
 629/* Make pointers available for printing early in the boot sequence. */
 630static int debug_boot_weak_hash __ro_after_init;
 631
 632static int __init debug_boot_weak_hash_enable(char *str)
 633{
 634        debug_boot_weak_hash = 1;
 635        pr_info("debug_boot_weak_hash enabled\n");
 636        return 0;
 637}
 638early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
 639
 640static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
 641static siphash_key_t ptr_key __read_mostly;
 642
 643static void enable_ptr_key_workfn(struct work_struct *work)
 644{
 645        get_random_bytes(&ptr_key, sizeof(ptr_key));
 646        /* Needs to run from preemptible context */
 647        static_branch_disable(&not_filled_random_ptr_key);
 648}
 649
 650static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
 651
 652static void fill_random_ptr_key(struct random_ready_callback *unused)
 653{
 654        /* This may be in an interrupt handler. */
 655        queue_work(system_unbound_wq, &enable_ptr_key_work);
 656}
 657
 658static struct random_ready_callback random_ready = {
 659        .func = fill_random_ptr_key
 660};
 661
 662static int __init initialize_ptr_random(void)
 663{
 664        int key_size = sizeof(ptr_key);
 665        int ret;
 666
 667        /* Use hw RNG if available. */
 668        if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
 669                static_branch_disable(&not_filled_random_ptr_key);
 670                return 0;
 671        }
 672
 673        ret = add_random_ready_callback(&random_ready);
 674        if (!ret) {
 675                return 0;
 676        } else if (ret == -EALREADY) {
 677                /* This is in preemptible context */
 678                enable_ptr_key_workfn(&enable_ptr_key_work);
 679                return 0;
 680        }
 681
 682        return ret;
 683}
 684early_initcall(initialize_ptr_random);
 685
 686/* Maps a pointer to a 32 bit unique identifier. */
 687static char *ptr_to_id(char *buf, char *end, const void *ptr,
 688                       struct printf_spec spec)
 689{
 690        const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
 691        unsigned long hashval;
 692
 693        /* When debugging early boot use non-cryptographically secure hash. */
 694        if (unlikely(debug_boot_weak_hash)) {
 695                hashval = hash_long((unsigned long)ptr, 32);
 696                return pointer_string(buf, end, (const void *)hashval, spec);
 697        }
 698
 699        if (static_branch_unlikely(&not_filled_random_ptr_key)) {
 700                spec.field_width = 2 * sizeof(ptr);
 701                /* string length must be less than default_width */
 702                return string(buf, end, str, spec);
 703        }
 704
 705#ifdef CONFIG_64BIT
 706        hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
 707        /*
 708         * Mask off the first 32 bits, this makes explicit that we have
 709         * modified the address (and 32 bits is plenty for a unique ID).
 710         */
 711        hashval = hashval & 0xffffffff;
 712#else
 713        hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
 714#endif
 715        return pointer_string(buf, end, (const void *)hashval, spec);
 716}
 717
 718static noinline_for_stack
 719char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
 720                  const char *fmt)
 721{
 722        const char *array[4], *s;
 723        const struct dentry *p;
 724        int depth;
 725        int i, n;
 726
 727        switch (fmt[1]) {
 728                case '2': case '3': case '4':
 729                        depth = fmt[1] - '0';
 730                        break;
 731                default:
 732                        depth = 1;
 733        }
 734
 735        rcu_read_lock();
 736        for (i = 0; i < depth; i++, d = p) {
 737                p = READ_ONCE(d->d_parent);
 738                array[i] = READ_ONCE(d->d_name.name);
 739                if (p == d) {
 740                        if (i)
 741                                array[i] = "";
 742                        i++;
 743                        break;
 744                }
 745        }
 746        s = array[--i];
 747        for (n = 0; n != spec.precision; n++, buf++) {
 748                char c = *s++;
 749                if (!c) {
 750                        if (!i)
 751                                break;
 752                        c = '/';
 753                        s = array[--i];
 754                }
 755                if (buf < end)
 756                        *buf = c;
 757        }
 758        rcu_read_unlock();
 759        return widen_string(buf, n, end, spec);
 760}
 761
 762#ifdef CONFIG_BLOCK
 763static noinline_for_stack
 764char *bdev_name(char *buf, char *end, struct block_device *bdev,
 765                struct printf_spec spec, const char *fmt)
 766{
 767        struct gendisk *hd = bdev->bd_disk;
 768        
 769        buf = string(buf, end, hd->disk_name, spec);
 770        if (bdev->bd_part->partno) {
 771                if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
 772                        if (buf < end)
 773                                *buf = 'p';
 774                        buf++;
 775                }
 776                buf = number(buf, end, bdev->bd_part->partno, spec);
 777        }
 778        return buf;
 779}
 780#endif
 781
 782static noinline_for_stack
 783char *symbol_string(char *buf, char *end, void *ptr,
 784                    struct printf_spec spec, const char *fmt)
 785{
 786        unsigned long value;
 787#ifdef CONFIG_KALLSYMS
 788        char sym[KSYM_SYMBOL_LEN];
 789#endif
 790
 791        if (fmt[1] == 'R')
 792                ptr = __builtin_extract_return_addr(ptr);
 793        value = (unsigned long)ptr;
 794
 795#ifdef CONFIG_KALLSYMS
 796        if (*fmt == 'B')
 797                sprint_backtrace(sym, value);
 798        else if (*fmt != 'f' && *fmt != 's')
 799                sprint_symbol(sym, value);
 800        else
 801                sprint_symbol_no_offset(sym, value);
 802
 803        return string(buf, end, sym, spec);
 804#else
 805        return special_hex_number(buf, end, value, sizeof(void *));
 806#endif
 807}
 808
 809static const struct printf_spec default_str_spec = {
 810        .field_width = -1,
 811        .precision = -1,
 812};
 813
 814static const struct printf_spec default_flag_spec = {
 815        .base = 16,
 816        .precision = -1,
 817        .flags = SPECIAL | SMALL,
 818};
 819
 820static const struct printf_spec default_dec_spec = {
 821        .base = 10,
 822        .precision = -1,
 823};
 824
 825static noinline_for_stack
 826char *resource_string(char *buf, char *end, struct resource *res,
 827                      struct printf_spec spec, const char *fmt)
 828{
 829#ifndef IO_RSRC_PRINTK_SIZE
 830#define IO_RSRC_PRINTK_SIZE     6
 831#endif
 832
 833#ifndef MEM_RSRC_PRINTK_SIZE
 834#define MEM_RSRC_PRINTK_SIZE    10
 835#endif
 836        static const struct printf_spec io_spec = {
 837                .base = 16,
 838                .field_width = IO_RSRC_PRINTK_SIZE,
 839                .precision = -1,
 840                .flags = SPECIAL | SMALL | ZEROPAD,
 841        };
 842        static const struct printf_spec mem_spec = {
 843                .base = 16,
 844                .field_width = MEM_RSRC_PRINTK_SIZE,
 845                .precision = -1,
 846                .flags = SPECIAL | SMALL | ZEROPAD,
 847        };
 848        static const struct printf_spec bus_spec = {
 849                .base = 16,
 850                .field_width = 2,
 851                .precision = -1,
 852                .flags = SMALL | ZEROPAD,
 853        };
 854        static const struct printf_spec str_spec = {
 855                .field_width = -1,
 856                .precision = 10,
 857                .flags = LEFT,
 858        };
 859
 860        /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
 861         * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
 862#define RSRC_BUF_SIZE           ((2 * sizeof(resource_size_t)) + 4)
 863#define FLAG_BUF_SIZE           (2 * sizeof(res->flags))
 864#define DECODED_BUF_SIZE        sizeof("[mem - 64bit pref window disabled]")
 865#define RAW_BUF_SIZE            sizeof("[mem - flags 0x]")
 866        char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
 867                     2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
 868
 869        char *p = sym, *pend = sym + sizeof(sym);
 870        int decode = (fmt[0] == 'R') ? 1 : 0;
 871        const struct printf_spec *specp;
 872
 873        *p++ = '[';
 874        if (res->flags & IORESOURCE_IO) {
 875                p = string(p, pend, "io  ", str_spec);
 876                specp = &io_spec;
 877        } else if (res->flags & IORESOURCE_MEM) {
 878                p = string(p, pend, "mem ", str_spec);
 879                specp = &mem_spec;
 880        } else if (res->flags & IORESOURCE_IRQ) {
 881                p = string(p, pend, "irq ", str_spec);
 882                specp = &default_dec_spec;
 883        } else if (res->flags & IORESOURCE_DMA) {
 884                p = string(p, pend, "dma ", str_spec);
 885                specp = &default_dec_spec;
 886        } else if (res->flags & IORESOURCE_BUS) {
 887                p = string(p, pend, "bus ", str_spec);
 888                specp = &bus_spec;
 889        } else {
 890                p = string(p, pend, "??? ", str_spec);
 891                specp = &mem_spec;
 892                decode = 0;
 893        }
 894        if (decode && res->flags & IORESOURCE_UNSET) {
 895                p = string(p, pend, "size ", str_spec);
 896                p = number(p, pend, resource_size(res), *specp);
 897        } else {
 898                p = number(p, pend, res->start, *specp);
 899                if (res->start != res->end) {
 900                        *p++ = '-';
 901                        p = number(p, pend, res->end, *specp);
 902                }
 903        }
 904        if (decode) {
 905                if (res->flags & IORESOURCE_MEM_64)
 906                        p = string(p, pend, " 64bit", str_spec);
 907                if (res->flags & IORESOURCE_PREFETCH)
 908                        p = string(p, pend, " pref", str_spec);
 909                if (res->flags & IORESOURCE_WINDOW)
 910                        p = string(p, pend, " window", str_spec);
 911                if (res->flags & IORESOURCE_DISABLED)
 912                        p = string(p, pend, " disabled", str_spec);
 913        } else {
 914                p = string(p, pend, " flags ", str_spec);
 915                p = number(p, pend, res->flags, default_flag_spec);
 916        }
 917        *p++ = ']';
 918        *p = '\0';
 919
 920        return string(buf, end, sym, spec);
 921}
 922
 923static noinline_for_stack
 924char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
 925                 const char *fmt)
 926{
 927        int i, len = 1;         /* if we pass '%ph[CDN]', field width remains
 928                                   negative value, fallback to the default */
 929        char separator;
 930
 931        if (spec.field_width == 0)
 932                /* nothing to print */
 933                return buf;
 934
 935        if (ZERO_OR_NULL_PTR(addr))
 936                /* NULL pointer */
 937                return string(buf, end, NULL, spec);
 938
 939        switch (fmt[1]) {
 940        case 'C':
 941                separator = ':';
 942                break;
 943        case 'D':
 944                separator = '-';
 945                break;
 946        case 'N':
 947                separator = 0;
 948                break;
 949        default:
 950                separator = ' ';
 951                break;
 952        }
 953
 954        if (spec.field_width > 0)
 955                len = min_t(int, spec.field_width, 64);
 956
 957        for (i = 0; i < len; ++i) {
 958                if (buf < end)
 959                        *buf = hex_asc_hi(addr[i]);
 960                ++buf;
 961                if (buf < end)
 962                        *buf = hex_asc_lo(addr[i]);
 963                ++buf;
 964
 965                if (separator && i != len - 1) {
 966                        if (buf < end)
 967                                *buf = separator;
 968                        ++buf;
 969                }
 970        }
 971
 972        return buf;
 973}
 974
 975static noinline_for_stack
 976char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
 977                    struct printf_spec spec, const char *fmt)
 978{
 979        const int CHUNKSZ = 32;
 980        int nr_bits = max_t(int, spec.field_width, 0);
 981        int i, chunksz;
 982        bool first = true;
 983
 984        /* reused to print numbers */
 985        spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
 986
 987        chunksz = nr_bits & (CHUNKSZ - 1);
 988        if (chunksz == 0)
 989                chunksz = CHUNKSZ;
 990
 991        i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
 992        for (; i >= 0; i -= CHUNKSZ) {
 993                u32 chunkmask, val;
 994                int word, bit;
 995
 996                chunkmask = ((1ULL << chunksz) - 1);
 997                word = i / BITS_PER_LONG;
 998                bit = i % BITS_PER_LONG;
 999                val = (bitmap[word] >> bit) & chunkmask;
1000
1001                if (!first) {
1002                        if (buf < end)
1003                                *buf = ',';
1004                        buf++;
1005                }
1006                first = false;
1007
1008                spec.field_width = DIV_ROUND_UP(chunksz, 4);
1009                buf = number(buf, end, val, spec);
1010
1011                chunksz = CHUNKSZ;
1012        }
1013        return buf;
1014}
1015
1016static noinline_for_stack
1017char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
1018                         struct printf_spec spec, const char *fmt)
1019{
1020        int nr_bits = max_t(int, spec.field_width, 0);
1021        /* current bit is 'cur', most recently seen range is [rbot, rtop] */
1022        int cur, rbot, rtop;
1023        bool first = true;
1024
1025        rbot = cur = find_first_bit(bitmap, nr_bits);
1026        while (cur < nr_bits) {
1027                rtop = cur;
1028                cur = find_next_bit(bitmap, nr_bits, cur + 1);
1029                if (cur < nr_bits && cur <= rtop + 1)
1030                        continue;
1031
1032                if (!first) {
1033                        if (buf < end)
1034                                *buf = ',';
1035                        buf++;
1036                }
1037                first = false;
1038
1039                buf = number(buf, end, rbot, default_dec_spec);
1040                if (rbot < rtop) {
1041                        if (buf < end)
1042                                *buf = '-';
1043                        buf++;
1044
1045                        buf = number(buf, end, rtop, default_dec_spec);
1046                }
1047
1048                rbot = cur;
1049        }
1050        return buf;
1051}
1052
1053static noinline_for_stack
1054char *mac_address_string(char *buf, char *end, u8 *addr,
1055                         struct printf_spec spec, const char *fmt)
1056{
1057        char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
1058        char *p = mac_addr;
1059        int i;
1060        char separator;
1061        bool reversed = false;
1062
1063        switch (fmt[1]) {
1064        case 'F':
1065                separator = '-';
1066                break;
1067
1068        case 'R':
1069                reversed = true;
1070                /* fall through */
1071
1072        default:
1073                separator = ':';
1074                break;
1075        }
1076
1077        for (i = 0; i < 6; i++) {
1078                if (reversed)
1079                        p = hex_byte_pack(p, addr[5 - i]);
1080                else
1081                        p = hex_byte_pack(p, addr[i]);
1082
1083                if (fmt[0] == 'M' && i != 5)
1084                        *p++ = separator;
1085        }
1086        *p = '\0';
1087
1088        return string(buf, end, mac_addr, spec);
1089}
1090
1091static noinline_for_stack
1092char *ip4_string(char *p, const u8 *addr, const char *fmt)
1093{
1094        int i;
1095        bool leading_zeros = (fmt[0] == 'i');
1096        int index;
1097        int step;
1098
1099        switch (fmt[2]) {
1100        case 'h':
1101#ifdef __BIG_ENDIAN
1102                index = 0;
1103                step = 1;
1104#else
1105                index = 3;
1106                step = -1;
1107#endif
1108                break;
1109        case 'l':
1110                index = 3;
1111                step = -1;
1112                break;
1113        case 'n':
1114        case 'b':
1115        default:
1116                index = 0;
1117                step = 1;
1118                break;
1119        }
1120        for (i = 0; i < 4; i++) {
1121                char temp[4] __aligned(2);      /* hold each IP quad in reverse order */
1122                int digits = put_dec_trunc8(temp, addr[index]) - temp;
1123                if (leading_zeros) {
1124                        if (digits < 3)
1125                                *p++ = '0';
1126                        if (digits < 2)
1127                                *p++ = '0';
1128                }
1129                /* reverse the digits in the quad */
1130                while (digits--)
1131                        *p++ = temp[digits];
1132                if (i < 3)
1133                        *p++ = '.';
1134                index += step;
1135        }
1136        *p = '\0';
1137
1138        return p;
1139}
1140
1141static noinline_for_stack
1142char *ip6_compressed_string(char *p, const char *addr)
1143{
1144        int i, j, range;
1145        unsigned char zerolength[8];
1146        int longest = 1;
1147        int colonpos = -1;
1148        u16 word;
1149        u8 hi, lo;
1150        bool needcolon = false;
1151        bool useIPv4;
1152        struct in6_addr in6;
1153
1154        memcpy(&in6, addr, sizeof(struct in6_addr));
1155
1156        useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1157
1158        memset(zerolength, 0, sizeof(zerolength));
1159
1160        if (useIPv4)
1161                range = 6;
1162        else
1163                range = 8;
1164
1165        /* find position of longest 0 run */
1166        for (i = 0; i < range; i++) {
1167                for (j = i; j < range; j++) {
1168                        if (in6.s6_addr16[j] != 0)
1169                                break;
1170                        zerolength[i]++;
1171                }
1172        }
1173        for (i = 0; i < range; i++) {
1174                if (zerolength[i] > longest) {
1175                        longest = zerolength[i];
1176                        colonpos = i;
1177                }
1178        }
1179        if (longest == 1)               /* don't compress a single 0 */
1180                colonpos = -1;
1181
1182        /* emit address */
1183        for (i = 0; i < range; i++) {
1184                if (i == colonpos) {
1185                        if (needcolon || i == 0)
1186                                *p++ = ':';
1187                        *p++ = ':';
1188                        needcolon = false;
1189                        i += longest - 1;
1190                        continue;
1191                }
1192                if (needcolon) {
1193                        *p++ = ':';
1194                        needcolon = false;
1195                }
1196                /* hex u16 without leading 0s */
1197                word = ntohs(in6.s6_addr16[i]);
1198                hi = word >> 8;
1199                lo = word & 0xff;
1200                if (hi) {
1201                        if (hi > 0x0f)
1202                                p = hex_byte_pack(p, hi);
1203                        else
1204                                *p++ = hex_asc_lo(hi);
1205                        p = hex_byte_pack(p, lo);
1206                }
1207                else if (lo > 0x0f)
1208                        p = hex_byte_pack(p, lo);
1209                else
1210                        *p++ = hex_asc_lo(lo);
1211                needcolon = true;
1212        }
1213
1214        if (useIPv4) {
1215                if (needcolon)
1216                        *p++ = ':';
1217                p = ip4_string(p, &in6.s6_addr[12], "I4");
1218        }
1219        *p = '\0';
1220
1221        return p;
1222}
1223
1224static noinline_for_stack
1225char *ip6_string(char *p, const char *addr, const char *fmt)
1226{
1227        int i;
1228
1229        for (i = 0; i < 8; i++) {
1230                p = hex_byte_pack(p, *addr++);
1231                p = hex_byte_pack(p, *addr++);
1232                if (fmt[0] == 'I' && i != 7)
1233                        *p++ = ':';
1234        }
1235        *p = '\0';
1236
1237        return p;
1238}
1239
1240static noinline_for_stack
1241char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1242                      struct printf_spec spec, const char *fmt)
1243{
1244        char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1245
1246        if (fmt[0] == 'I' && fmt[2] == 'c')
1247                ip6_compressed_string(ip6_addr, addr);
1248        else
1249                ip6_string(ip6_addr, addr, fmt);
1250
1251        return string(buf, end, ip6_addr, spec);
1252}
1253
1254static noinline_for_stack
1255char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1256                      struct printf_spec spec, const char *fmt)
1257{
1258        char ip4_addr[sizeof("255.255.255.255")];
1259
1260        ip4_string(ip4_addr, addr, fmt);
1261
1262        return string(buf, end, ip4_addr, spec);
1263}
1264
1265static noinline_for_stack
1266char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1267                         struct printf_spec spec, const char *fmt)
1268{
1269        bool have_p = false, have_s = false, have_f = false, have_c = false;
1270        char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1271                      sizeof(":12345") + sizeof("/123456789") +
1272                      sizeof("%1234567890")];
1273        char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1274        const u8 *addr = (const u8 *) &sa->sin6_addr;
1275        char fmt6[2] = { fmt[0], '6' };
1276        u8 off = 0;
1277
1278        fmt++;
1279        while (isalpha(*++fmt)) {
1280                switch (*fmt) {
1281                case 'p':
1282                        have_p = true;
1283                        break;
1284                case 'f':
1285                        have_f = true;
1286                        break;
1287                case 's':
1288                        have_s = true;
1289                        break;
1290                case 'c':
1291                        have_c = true;
1292                        break;
1293                }
1294        }
1295
1296        if (have_p || have_s || have_f) {
1297                *p = '[';
1298                off = 1;
1299        }
1300
1301        if (fmt6[0] == 'I' && have_c)
1302                p = ip6_compressed_string(ip6_addr + off, addr);
1303        else
1304                p = ip6_string(ip6_addr + off, addr, fmt6);
1305
1306        if (have_p || have_s || have_f)
1307                *p++ = ']';
1308
1309        if (have_p) {
1310                *p++ = ':';
1311                p = number(p, pend, ntohs(sa->sin6_port), spec);
1312        }
1313        if (have_f) {
1314                *p++ = '/';
1315                p = number(p, pend, ntohl(sa->sin6_flowinfo &
1316                                          IPV6_FLOWINFO_MASK), spec);
1317        }
1318        if (have_s) {
1319                *p++ = '%';
1320                p = number(p, pend, sa->sin6_scope_id, spec);
1321        }
1322        *p = '\0';
1323
1324        return string(buf, end, ip6_addr, spec);
1325}
1326
1327static noinline_for_stack
1328char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1329                         struct printf_spec spec, const char *fmt)
1330{
1331        bool have_p = false;
1332        char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1333        char *pend = ip4_addr + sizeof(ip4_addr);
1334        const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1335        char fmt4[3] = { fmt[0], '4', 0 };
1336
1337        fmt++;
1338        while (isalpha(*++fmt)) {
1339                switch (*fmt) {
1340                case 'p':
1341                        have_p = true;
1342                        break;
1343                case 'h':
1344                case 'l':
1345                case 'n':
1346                case 'b':
1347                        fmt4[2] = *fmt;
1348                        break;
1349                }
1350        }
1351
1352        p = ip4_string(ip4_addr, addr, fmt4);
1353        if (have_p) {
1354                *p++ = ':';
1355                p = number(p, pend, ntohs(sa->sin_port), spec);
1356        }
1357        *p = '\0';
1358
1359        return string(buf, end, ip4_addr, spec);
1360}
1361
1362static noinline_for_stack
1363char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1364                     const char *fmt)
1365{
1366        bool found = true;
1367        int count = 1;
1368        unsigned int flags = 0;
1369        int len;
1370
1371        if (spec.field_width == 0)
1372                return buf;                             /* nothing to print */
1373
1374        if (ZERO_OR_NULL_PTR(addr))
1375                return string(buf, end, NULL, spec);    /* NULL pointer */
1376
1377
1378        do {
1379                switch (fmt[count++]) {
1380                case 'a':
1381                        flags |= ESCAPE_ANY;
1382                        break;
1383                case 'c':
1384                        flags |= ESCAPE_SPECIAL;
1385                        break;
1386                case 'h':
1387                        flags |= ESCAPE_HEX;
1388                        break;
1389                case 'n':
1390                        flags |= ESCAPE_NULL;
1391                        break;
1392                case 'o':
1393                        flags |= ESCAPE_OCTAL;
1394                        break;
1395                case 'p':
1396                        flags |= ESCAPE_NP;
1397                        break;
1398                case 's':
1399                        flags |= ESCAPE_SPACE;
1400                        break;
1401                default:
1402                        found = false;
1403                        break;
1404                }
1405        } while (found);
1406
1407        if (!flags)
1408                flags = ESCAPE_ANY_NP;
1409
1410        len = spec.field_width < 0 ? 1 : spec.field_width;
1411
1412        /*
1413         * string_escape_mem() writes as many characters as it can to
1414         * the given buffer, and returns the total size of the output
1415         * had the buffer been big enough.
1416         */
1417        buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1418
1419        return buf;
1420}
1421
1422static noinline_for_stack
1423char *uuid_string(char *buf, char *end, const u8 *addr,
1424                  struct printf_spec spec, const char *fmt)
1425{
1426        char uuid[UUID_STRING_LEN + 1];
1427        char *p = uuid;
1428        int i;
1429        const u8 *index = uuid_index;
1430        bool uc = false;
1431
1432        switch (*(++fmt)) {
1433        case 'L':
1434                uc = true;              /* fall-through */
1435        case 'l':
1436                index = guid_index;
1437                break;
1438        case 'B':
1439                uc = true;
1440                break;
1441        }
1442
1443        for (i = 0; i < 16; i++) {
1444                if (uc)
1445                        p = hex_byte_pack_upper(p, addr[index[i]]);
1446                else
1447                        p = hex_byte_pack(p, addr[index[i]]);
1448                switch (i) {
1449                case 3:
1450                case 5:
1451                case 7:
1452                case 9:
1453                        *p++ = '-';
1454                        break;
1455                }
1456        }
1457
1458        *p = 0;
1459
1460        return string(buf, end, uuid, spec);
1461}
1462
1463int kptr_restrict __read_mostly;
1464
1465static noinline_for_stack
1466char *restricted_pointer(char *buf, char *end, const void *ptr,
1467                         struct printf_spec spec)
1468{
1469        switch (kptr_restrict) {
1470        case 0:
1471                /* Always print %pK values */
1472                break;
1473        case 1: {
1474                const struct cred *cred;
1475
1476                /*
1477                 * kptr_restrict==1 cannot be used in IRQ context
1478                 * because its test for CAP_SYSLOG would be meaningless.
1479                 */
1480                if (in_irq() || in_serving_softirq() || in_nmi()) {
1481                        if (spec.field_width == -1)
1482                                spec.field_width = 2 * sizeof(ptr);
1483                        return string(buf, end, "pK-error", spec);
1484                }
1485
1486                /*
1487                 * Only print the real pointer value if the current
1488                 * process has CAP_SYSLOG and is running with the
1489                 * same credentials it started with. This is because
1490                 * access to files is checked at open() time, but %pK
1491                 * checks permission at read() time. We don't want to
1492                 * leak pointer values if a binary opens a file using
1493                 * %pK and then elevates privileges before reading it.
1494                 */
1495                cred = current_cred();
1496                if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1497                    !uid_eq(cred->euid, cred->uid) ||
1498                    !gid_eq(cred->egid, cred->gid))
1499                        ptr = NULL;
1500                break;
1501        }
1502        case 2:
1503        default:
1504                /* Always print 0's for %pK */
1505                ptr = NULL;
1506                break;
1507        }
1508
1509        return pointer_string(buf, end, ptr, spec);
1510}
1511
1512static noinline_for_stack
1513char *netdev_bits(char *buf, char *end, const void *addr,
1514                  struct printf_spec spec,  const char *fmt)
1515{
1516        unsigned long long num;
1517        int size;
1518
1519        switch (fmt[1]) {
1520        case 'F':
1521                num = *(const netdev_features_t *)addr;
1522                size = sizeof(netdev_features_t);
1523                break;
1524        default:
1525                return ptr_to_id(buf, end, addr, spec);
1526        }
1527
1528        return special_hex_number(buf, end, num, size);
1529}
1530
1531static noinline_for_stack
1532char *address_val(char *buf, char *end, const void *addr, const char *fmt)
1533{
1534        unsigned long long num;
1535        int size;
1536
1537        switch (fmt[1]) {
1538        case 'd':
1539                num = *(const dma_addr_t *)addr;
1540                size = sizeof(dma_addr_t);
1541                break;
1542        case 'p':
1543        default:
1544                num = *(const phys_addr_t *)addr;
1545                size = sizeof(phys_addr_t);
1546                break;
1547        }
1548
1549        return special_hex_number(buf, end, num, size);
1550}
1551
1552static noinline_for_stack
1553char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1554            const char *fmt)
1555{
1556        if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
1557                return string(buf, end, NULL, spec);
1558
1559        switch (fmt[1]) {
1560        case 'n':
1561        default:
1562#ifdef CONFIG_COMMON_CLK
1563                return string(buf, end, __clk_get_name(clk), spec);
1564#else
1565                return ptr_to_id(buf, end, clk, spec);
1566#endif
1567        }
1568}
1569
1570static
1571char *format_flags(char *buf, char *end, unsigned long flags,
1572                                        const struct trace_print_flags *names)
1573{
1574        unsigned long mask;
1575
1576        for ( ; flags && names->name; names++) {
1577                mask = names->mask;
1578                if ((flags & mask) != mask)
1579                        continue;
1580
1581                buf = string(buf, end, names->name, default_str_spec);
1582
1583                flags &= ~mask;
1584                if (flags) {
1585                        if (buf < end)
1586                                *buf = '|';
1587                        buf++;
1588                }
1589        }
1590
1591        if (flags)
1592                buf = number(buf, end, flags, default_flag_spec);
1593
1594        return buf;
1595}
1596
1597static noinline_for_stack
1598char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
1599{
1600        unsigned long flags;
1601        const struct trace_print_flags *names;
1602
1603        switch (fmt[1]) {
1604        case 'p':
1605                flags = *(unsigned long *)flags_ptr;
1606                /* Remove zone id */
1607                flags &= (1UL << NR_PAGEFLAGS) - 1;
1608                names = pageflag_names;
1609                break;
1610        case 'v':
1611                flags = *(unsigned long *)flags_ptr;
1612                names = vmaflag_names;
1613                break;
1614        case 'g':
1615                flags = *(gfp_t *)flags_ptr;
1616                names = gfpflag_names;
1617                break;
1618        default:
1619                WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
1620                return buf;
1621        }
1622
1623        return format_flags(buf, end, flags, names);
1624}
1625
1626static const char *device_node_name_for_depth(const struct device_node *np, int depth)
1627{
1628        for ( ; np && depth; depth--)
1629                np = np->parent;
1630
1631        return kbasename(np->full_name);
1632}
1633
1634static noinline_for_stack
1635char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end)
1636{
1637        int depth;
1638        const struct device_node *parent = np->parent;
1639
1640        /* special case for root node */
1641        if (!parent)
1642                return string(buf, end, "/", default_str_spec);
1643
1644        for (depth = 0; parent->parent; depth++)
1645                parent = parent->parent;
1646
1647        for ( ; depth >= 0; depth--) {
1648                buf = string(buf, end, "/", default_str_spec);
1649                buf = string(buf, end, device_node_name_for_depth(np, depth),
1650                             default_str_spec);
1651        }
1652        return buf;
1653}
1654
1655static noinline_for_stack
1656char *device_node_string(char *buf, char *end, struct device_node *dn,
1657                         struct printf_spec spec, const char *fmt)
1658{
1659        char tbuf[sizeof("xxxx") + 1];
1660        const char *p;
1661        int ret;
1662        char *buf_start = buf;
1663        struct property *prop;
1664        bool has_mult, pass;
1665        static const struct printf_spec num_spec = {
1666                .flags = SMALL,
1667                .field_width = -1,
1668                .precision = -1,
1669                .base = 10,
1670        };
1671
1672        struct printf_spec str_spec = spec;
1673        str_spec.field_width = -1;
1674
1675        if (!IS_ENABLED(CONFIG_OF))
1676                return string(buf, end, "(!OF)", spec);
1677
1678        if ((unsigned long)dn < PAGE_SIZE)
1679                return string(buf, end, "(null)", spec);
1680
1681        /* simple case without anything any more format specifiers */
1682        fmt++;
1683        if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
1684                fmt = "f";
1685
1686        for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
1687                int precision;
1688                if (pass) {
1689                        if (buf < end)
1690                                *buf = ':';
1691                        buf++;
1692                }
1693
1694                switch (*fmt) {
1695                case 'f':       /* full_name */
1696                        buf = device_node_gen_full_name(dn, buf, end);
1697                        break;
1698                case 'n':       /* name */
1699                        p = kbasename(of_node_full_name(dn));
1700                        precision = str_spec.precision;
1701                        str_spec.precision = strchrnul(p, '@') - p;
1702                        buf = string(buf, end, p, str_spec);
1703                        str_spec.precision = precision;
1704                        break;
1705                case 'p':       /* phandle */
1706                        buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
1707                        break;
1708                case 'P':       /* path-spec */
1709                        p = kbasename(of_node_full_name(dn));
1710                        if (!p[1])
1711                                p = "/";
1712                        buf = string(buf, end, p, str_spec);
1713                        break;
1714                case 'F':       /* flags */
1715                        tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
1716                        tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
1717                        tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
1718                        tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
1719                        tbuf[4] = 0;
1720                        buf = string(buf, end, tbuf, str_spec);
1721                        break;
1722                case 'c':       /* major compatible string */
1723                        ret = of_property_read_string(dn, "compatible", &p);
1724                        if (!ret)
1725                                buf = string(buf, end, p, str_spec);
1726                        break;
1727                case 'C':       /* full compatible string */
1728                        has_mult = false;
1729                        of_property_for_each_string(dn, "compatible", prop, p) {
1730                                if (has_mult)
1731                                        buf = string(buf, end, ",", str_spec);
1732                                buf = string(buf, end, "\"", str_spec);
1733                                buf = string(buf, end, p, str_spec);
1734                                buf = string(buf, end, "\"", str_spec);
1735
1736                                has_mult = true;
1737                        }
1738                        break;
1739                default:
1740                        break;
1741                }
1742        }
1743
1744        return widen_string(buf, buf - buf_start, end, spec);
1745}
1746
1747/*
1748 * Show a '%p' thing.  A kernel extension is that the '%p' is followed
1749 * by an extra set of alphanumeric characters that are extended format
1750 * specifiers.
1751 *
1752 * Please update scripts/checkpatch.pl when adding/removing conversion
1753 * characters.  (Search for "check for vsprintf extension").
1754 *
1755 * Right now we handle:
1756 *
1757 * - 'S' For symbolic direct pointers (or function descriptors) with offset
1758 * - 's' For symbolic direct pointers (or function descriptors) without offset
1759 * - 'F' Same as 'S'
1760 * - 'f' Same as 's'
1761 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1762 * - 'B' For backtraced symbolic direct pointers with offset
1763 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1764 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1765 * - 'b[l]' For a bitmap, the number of bits is determined by the field
1766 *       width which must be explicitly specified either as part of the
1767 *       format string '%32b[l]' or through '%*b[l]', [l] selects
1768 *       range-list format instead of hex format
1769 * - 'M' For a 6-byte MAC address, it prints the address in the
1770 *       usual colon-separated hex notation
1771 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1772 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1773 *       with a dash-separated hex notation
1774 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1775 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1776 *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1777 *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
1778 *       [S][pfs]
1779 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1780 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1781 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1782 *       IPv6 omits the colons (01020304...0f)
1783 *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1784 *       [S][pfs]
1785 *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1786 *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1787 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1788 * - 'I[6S]c' for IPv6 addresses printed as specified by
1789 *       http://tools.ietf.org/html/rfc5952
1790 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1791 *                of the following flags (see string_escape_mem() for the
1792 *                details):
1793 *                  a - ESCAPE_ANY
1794 *                  c - ESCAPE_SPECIAL
1795 *                  h - ESCAPE_HEX
1796 *                  n - ESCAPE_NULL
1797 *                  o - ESCAPE_OCTAL
1798 *                  p - ESCAPE_NP
1799 *                  s - ESCAPE_SPACE
1800 *                By default ESCAPE_ANY_NP is used.
1801 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1802 *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1803 *       Options for %pU are:
1804 *         b big endian lower case hex (default)
1805 *         B big endian UPPER case hex
1806 *         l little endian lower case hex
1807 *         L little endian UPPER case hex
1808 *           big endian output byte order is:
1809 *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1810 *           little endian output byte order is:
1811 *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1812 * - 'V' For a struct va_format which contains a format string * and va_list *,
1813 *       call vsnprintf(->format, *->va_list).
1814 *       Implements a "recursive vsnprintf".
1815 *       Do not use this feature without some mechanism to verify the
1816 *       correctness of the format string and va_list arguments.
1817 * - 'K' For a kernel pointer that should be hidden from unprivileged users
1818 * - 'NF' For a netdev_features_t
1819 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1820 *            a certain separator (' ' by default):
1821 *              C colon
1822 *              D dash
1823 *              N no separator
1824 *            The maximum supported length is 64 bytes of the input. Consider
1825 *            to use print_hex_dump() for the larger input.
1826 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1827 *           (default assumed to be phys_addr_t, passed by reference)
1828 * - 'd[234]' For a dentry name (optionally 2-4 last components)
1829 * - 'D[234]' Same as 'd' but for a struct file
1830 * - 'g' For block_device name (gendisk + partition number)
1831 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
1832 *       (legacy clock framework) of the clock
1833 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
1834 *        (legacy clock framework) of the clock
1835 * - 'Cr' For a clock, it prints the current rate of the clock
1836 * - 'G' For flags to be printed as a collection of symbolic strings that would
1837 *       construct the specific value. Supported flags given by option:
1838 *       p page flags (see struct page) given as pointer to unsigned long
1839 *       g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
1840 *       v vma flags (VM_*) given as pointer to unsigned long
1841 * - 'OF[fnpPcCF]'  For a device tree object
1842 *                  Without any optional arguments prints the full_name
1843 *                  f device node full_name
1844 *                  n device node name
1845 *                  p device node phandle
1846 *                  P device node path spec (name + @unit)
1847 *                  F device node flags
1848 *                  c major compatible string
1849 *                  C full compatible string
1850 * - 'x' For printing the address. Equivalent to "%lx".
1851 *
1852 * ** When making changes please also update:
1853 *      Documentation/core-api/printk-formats.rst
1854 *
1855 * Note: The default behaviour (unadorned %p) is to hash the address,
1856 * rendering it useful as a unique identifier.
1857 */
1858static noinline_for_stack
1859char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1860              struct printf_spec spec)
1861{
1862        const int default_width = 2 * sizeof(void *);
1863
1864        if (!ptr && *fmt != 'K' && *fmt != 'x') {
1865                /*
1866                 * Print (null) with the same width as a pointer so it makes
1867                 * tabular output look nice.
1868                 */
1869                if (spec.field_width == -1)
1870                        spec.field_width = default_width;
1871                return string(buf, end, "(null)", spec);
1872        }
1873
1874        switch (*fmt) {
1875        case 'F':
1876        case 'f':
1877        case 'S':
1878        case 's':
1879                ptr = dereference_symbol_descriptor(ptr);
1880                /* Fallthrough */
1881        case 'B':
1882                return symbol_string(buf, end, ptr, spec, fmt);
1883        case 'R':
1884        case 'r':
1885                return resource_string(buf, end, ptr, spec, fmt);
1886        case 'h':
1887                return hex_string(buf, end, ptr, spec, fmt);
1888        case 'b':
1889                switch (fmt[1]) {
1890                case 'l':
1891                        return bitmap_list_string(buf, end, ptr, spec, fmt);
1892                default:
1893                        return bitmap_string(buf, end, ptr, spec, fmt);
1894                }
1895        case 'M':                       /* Colon separated: 00:01:02:03:04:05 */
1896        case 'm':                       /* Contiguous: 000102030405 */
1897                                        /* [mM]F (FDDI) */
1898                                        /* [mM]R (Reverse order; Bluetooth) */
1899                return mac_address_string(buf, end, ptr, spec, fmt);
1900        case 'I':                       /* Formatted IP supported
1901                                         * 4:   1.2.3.4
1902                                         * 6:   0001:0203:...:0708
1903                                         * 6c:  1::708 or 1::1.2.3.4
1904                                         */
1905        case 'i':                       /* Contiguous:
1906                                         * 4:   001.002.003.004
1907                                         * 6:   000102...0f
1908                                         */
1909                switch (fmt[1]) {
1910                case '6':
1911                        return ip6_addr_string(buf, end, ptr, spec, fmt);
1912                case '4':
1913                        return ip4_addr_string(buf, end, ptr, spec, fmt);
1914                case 'S': {
1915                        const union {
1916                                struct sockaddr         raw;
1917                                struct sockaddr_in      v4;
1918                                struct sockaddr_in6     v6;
1919                        } *sa = ptr;
1920
1921                        switch (sa->raw.sa_family) {
1922                        case AF_INET:
1923                                return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1924                        case AF_INET6:
1925                                return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1926                        default:
1927                                return string(buf, end, "(invalid address)", spec);
1928                        }}
1929                }
1930                break;
1931        case 'E':
1932                return escaped_string(buf, end, ptr, spec, fmt);
1933        case 'U':
1934                return uuid_string(buf, end, ptr, spec, fmt);
1935        case 'V':
1936                {
1937                        va_list va;
1938
1939                        va_copy(va, *((struct va_format *)ptr)->va);
1940                        buf += vsnprintf(buf, end > buf ? end - buf : 0,
1941                                         ((struct va_format *)ptr)->fmt, va);
1942                        va_end(va);
1943                        return buf;
1944                }
1945        case 'K':
1946                if (!kptr_restrict)
1947                        break;
1948                return restricted_pointer(buf, end, ptr, spec);
1949        case 'N':
1950                return netdev_bits(buf, end, ptr, spec, fmt);
1951        case 'a':
1952                return address_val(buf, end, ptr, fmt);
1953        case 'd':
1954                return dentry_name(buf, end, ptr, spec, fmt);
1955        case 'C':
1956                return clock(buf, end, ptr, spec, fmt);
1957        case 'D':
1958                return dentry_name(buf, end,
1959                                   ((const struct file *)ptr)->f_path.dentry,
1960                                   spec, fmt);
1961#ifdef CONFIG_BLOCK
1962        case 'g':
1963                return bdev_name(buf, end, ptr, spec, fmt);
1964#endif
1965
1966        case 'G':
1967                return flags_string(buf, end, ptr, fmt);
1968        case 'O':
1969                switch (fmt[1]) {
1970                case 'F':
1971                        return device_node_string(buf, end, ptr, spec, fmt + 1);
1972                }
1973                break;
1974        case 'x':
1975                return pointer_string(buf, end, ptr, spec);
1976        }
1977
1978        /* default is to _not_ leak addresses, hash before printing */
1979        return ptr_to_id(buf, end, ptr, spec);
1980}
1981
1982/*
1983 * Helper function to decode printf style format.
1984 * Each call decode a token from the format and return the
1985 * number of characters read (or likely the delta where it wants
1986 * to go on the next call).
1987 * The decoded token is returned through the parameters
1988 *
1989 * 'h', 'l', or 'L' for integer fields
1990 * 'z' support added 23/7/1999 S.H.
1991 * 'z' changed to 'Z' --davidm 1/25/99
1992 * 'Z' changed to 'z' --adobriyan 2017-01-25
1993 * 't' added for ptrdiff_t
1994 *
1995 * @fmt: the format string
1996 * @type of the token returned
1997 * @flags: various flags such as +, -, # tokens..
1998 * @field_width: overwritten width
1999 * @base: base of the number (octal, hex, ...)
2000 * @precision: precision of a number
2001 * @qualifier: qualifier of a number (long, size_t, ...)
2002 */
2003static noinline_for_stack
2004int format_decode(const char *fmt, struct printf_spec *spec)
2005{
2006        const char *start = fmt;
2007        char qualifier;
2008
2009        /* we finished early by reading the field width */
2010        if (spec->type == FORMAT_TYPE_WIDTH) {
2011                if (spec->field_width < 0) {
2012                        spec->field_width = -spec->field_width;
2013                        spec->flags |= LEFT;
2014                }
2015                spec->type = FORMAT_TYPE_NONE;
2016                goto precision;
2017        }
2018
2019        /* we finished early by reading the precision */
2020        if (spec->type == FORMAT_TYPE_PRECISION) {
2021                if (spec->precision < 0)
2022                        spec->precision = 0;
2023
2024                spec->type = FORMAT_TYPE_NONE;
2025                goto qualifier;
2026        }
2027
2028        /* By default */
2029        spec->type = FORMAT_TYPE_NONE;
2030
2031        for (; *fmt ; ++fmt) {
2032                if (*fmt == '%')
2033                        break;
2034        }
2035
2036        /* Return the current non-format string */
2037        if (fmt != start || !*fmt)
2038                return fmt - start;
2039
2040        /* Process flags */
2041        spec->flags = 0;
2042
2043        while (1) { /* this also skips first '%' */
2044                bool found = true;
2045
2046                ++fmt;
2047
2048                switch (*fmt) {
2049                case '-': spec->flags |= LEFT;    break;
2050                case '+': spec->flags |= PLUS;    break;
2051                case ' ': spec->flags |= SPACE;   break;
2052                case '#': spec->flags |= SPECIAL; break;
2053                case '0': spec->flags |= ZEROPAD; break;
2054                default:  found = false;
2055                }
2056
2057                if (!found)
2058                        break;
2059        }
2060
2061        /* get field width */
2062        spec->field_width = -1;
2063
2064        if (isdigit(*fmt))
2065                spec->field_width = skip_atoi(&fmt);
2066        else if (*fmt == '*') {
2067                /* it's the next argument */
2068                spec->type = FORMAT_TYPE_WIDTH;
2069                return ++fmt - start;
2070        }
2071
2072precision:
2073        /* get the precision */
2074        spec->precision = -1;
2075        if (*fmt == '.') {
2076                ++fmt;
2077                if (isdigit(*fmt)) {
2078                        spec->precision = skip_atoi(&fmt);
2079                        if (spec->precision < 0)
2080                                spec->precision = 0;
2081                } else if (*fmt == '*') {
2082                        /* it's the next argument */
2083                        spec->type = FORMAT_TYPE_PRECISION;
2084                        return ++fmt - start;
2085                }
2086        }
2087
2088qualifier:
2089        /* get the conversion qualifier */
2090        qualifier = 0;
2091        if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2092            *fmt == 'z' || *fmt == 't') {
2093                qualifier = *fmt++;
2094                if (unlikely(qualifier == *fmt)) {
2095                        if (qualifier == 'l') {
2096                                qualifier = 'L';
2097                                ++fmt;
2098                        } else if (qualifier == 'h') {
2099                                qualifier = 'H';
2100                                ++fmt;
2101                        }
2102                }
2103        }
2104
2105        /* default base */
2106        spec->base = 10;
2107        switch (*fmt) {
2108        case 'c':
2109                spec->type = FORMAT_TYPE_CHAR;
2110                return ++fmt - start;
2111
2112        case 's':
2113                spec->type = FORMAT_TYPE_STR;
2114                return ++fmt - start;
2115
2116        case 'p':
2117                spec->type = FORMAT_TYPE_PTR;
2118                return ++fmt - start;
2119
2120        case '%':
2121                spec->type = FORMAT_TYPE_PERCENT_CHAR;
2122                return ++fmt - start;
2123
2124        /* integer number formats - set up the flags and "break" */
2125        case 'o':
2126                spec->base = 8;
2127                break;
2128
2129        case 'x':
2130                spec->flags |= SMALL;
2131                /* fall through */
2132
2133        case 'X':
2134                spec->base = 16;
2135                break;
2136
2137        case 'd':
2138        case 'i':
2139                spec->flags |= SIGN;
2140        case 'u':
2141                break;
2142
2143        case 'n':
2144                /*
2145                 * Since %n poses a greater security risk than
2146                 * utility, treat it as any other invalid or
2147                 * unsupported format specifier.
2148                 */
2149                /* Fall-through */
2150
2151        default:
2152                WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2153                spec->type = FORMAT_TYPE_INVALID;
2154                return fmt - start;
2155        }
2156
2157        if (qualifier == 'L')
2158                spec->type = FORMAT_TYPE_LONG_LONG;
2159        else if (qualifier == 'l') {
2160                BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2161                spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2162        } else if (qualifier == 'z') {
2163                spec->type = FORMAT_TYPE_SIZE_T;
2164        } else if (qualifier == 't') {
2165                spec->type = FORMAT_TYPE_PTRDIFF;
2166        } else if (qualifier == 'H') {
2167                BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2168                spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2169        } else if (qualifier == 'h') {
2170                BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2171                spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2172        } else {
2173                BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2174                spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2175        }
2176
2177        return ++fmt - start;
2178}
2179
2180static void
2181set_field_width(struct printf_spec *spec, int width)
2182{
2183        spec->field_width = width;
2184        if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2185                spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2186        }
2187}
2188
2189static void
2190set_precision(struct printf_spec *spec, int prec)
2191{
2192        spec->precision = prec;
2193        if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2194                spec->precision = clamp(prec, 0, PRECISION_MAX);
2195        }
2196}
2197
2198/**
2199 * vsnprintf - Format a string and place it in a buffer
2200 * @buf: The buffer to place the result into
2201 * @size: The size of the buffer, including the trailing null space
2202 * @fmt: The format string to use
2203 * @args: Arguments for the format string
2204 *
2205 * This function generally follows C99 vsnprintf, but has some
2206 * extensions and a few limitations:
2207 *
2208 *  - ``%n`` is unsupported
2209 *  - ``%p*`` is handled by pointer()
2210 *
2211 * See pointer() or Documentation/core-api/printk-formats.rst for more
2212 * extensive description.
2213 *
2214 * **Please update the documentation in both places when making changes**
2215 *
2216 * The return value is the number of characters which would
2217 * be generated for the given input, excluding the trailing
2218 * '\0', as per ISO C99. If you want to have the exact
2219 * number of characters written into @buf as return value
2220 * (not including the trailing '\0'), use vscnprintf(). If the
2221 * return is greater than or equal to @size, the resulting
2222 * string is truncated.
2223 *
2224 * If you're not already dealing with a va_list consider using snprintf().
2225 */
2226int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2227{
2228        unsigned long long num;
2229        char *str, *end;
2230        struct printf_spec spec = {0};
2231
2232        /* Reject out-of-range values early.  Large positive sizes are
2233           used for unknown buffer sizes. */
2234        if (WARN_ON_ONCE(size > INT_MAX))
2235                return 0;
2236
2237        str = buf;
2238        end = buf + size;
2239
2240        /* Make sure end is always >= buf */
2241        if (end < buf) {
2242                end = ((void *)-1);
2243                size = end - buf;
2244        }
2245
2246        while (*fmt) {
2247                const char *old_fmt = fmt;
2248                int read = format_decode(fmt, &spec);
2249
2250                fmt += read;
2251
2252                switch (spec.type) {
2253                case FORMAT_TYPE_NONE: {
2254                        int copy = read;
2255                        if (str < end) {
2256                                if (copy > end - str)
2257                                        copy = end - str;
2258                                memcpy(str, old_fmt, copy);
2259                        }
2260                        str += read;
2261                        break;
2262                }
2263
2264                case FORMAT_TYPE_WIDTH:
2265                        set_field_width(&spec, va_arg(args, int));
2266                        break;
2267
2268                case FORMAT_TYPE_PRECISION:
2269                        set_precision(&spec, va_arg(args, int));
2270                        break;
2271
2272                case FORMAT_TYPE_CHAR: {
2273                        char c;
2274
2275                        if (!(spec.flags & LEFT)) {
2276                                while (--spec.field_width > 0) {
2277                                        if (str < end)
2278                                                *str = ' ';
2279                                        ++str;
2280
2281                                }
2282                        }
2283                        c = (unsigned char) va_arg(args, int);
2284                        if (str < end)
2285                                *str = c;
2286                        ++str;
2287                        while (--spec.field_width > 0) {
2288                                if (str < end)
2289                                        *str = ' ';
2290                                ++str;
2291                        }
2292                        break;
2293                }
2294
2295                case FORMAT_TYPE_STR:
2296                        str = string(str, end, va_arg(args, char *), spec);
2297                        break;
2298
2299                case FORMAT_TYPE_PTR:
2300                        str = pointer(fmt, str, end, va_arg(args, void *),
2301                                      spec);
2302                        while (isalnum(*fmt))
2303                                fmt++;
2304                        break;
2305
2306                case FORMAT_TYPE_PERCENT_CHAR:
2307                        if (str < end)
2308                                *str = '%';
2309                        ++str;
2310                        break;
2311
2312                case FORMAT_TYPE_INVALID:
2313                        /*
2314                         * Presumably the arguments passed gcc's type
2315                         * checking, but there is no safe or sane way
2316                         * for us to continue parsing the format and
2317                         * fetching from the va_list; the remaining
2318                         * specifiers and arguments would be out of
2319                         * sync.
2320                         */
2321                        goto out;
2322
2323                default:
2324                        switch (spec.type) {
2325                        case FORMAT_TYPE_LONG_LONG:
2326                                num = va_arg(args, long long);
2327                                break;
2328                        case FORMAT_TYPE_ULONG:
2329                                num = va_arg(args, unsigned long);
2330                                break;
2331                        case FORMAT_TYPE_LONG:
2332                                num = va_arg(args, long);
2333                                break;
2334                        case FORMAT_TYPE_SIZE_T:
2335                                if (spec.flags & SIGN)
2336                                        num = va_arg(args, ssize_t);
2337                                else
2338                                        num = va_arg(args, size_t);
2339                                break;
2340                        case FORMAT_TYPE_PTRDIFF:
2341                                num = va_arg(args, ptrdiff_t);
2342                                break;
2343                        case FORMAT_TYPE_UBYTE:
2344                                num = (unsigned char) va_arg(args, int);
2345                                break;
2346                        case FORMAT_TYPE_BYTE:
2347                                num = (signed char) va_arg(args, int);
2348                                break;
2349                        case FORMAT_TYPE_USHORT:
2350                                num = (unsigned short) va_arg(args, int);
2351                                break;
2352                        case FORMAT_TYPE_SHORT:
2353                                num = (short) va_arg(args, int);
2354                                break;
2355                        case FORMAT_TYPE_INT:
2356                                num = (int) va_arg(args, int);
2357                                break;
2358                        default:
2359                                num = va_arg(args, unsigned int);
2360                        }
2361
2362                        str = number(str, end, num, spec);
2363                }
2364        }
2365
2366out:
2367        if (size > 0) {
2368                if (str < end)
2369                        *str = '\0';
2370                else
2371                        end[-1] = '\0';
2372        }
2373
2374        /* the trailing null byte doesn't count towards the total */
2375        return str-buf;
2376
2377}
2378EXPORT_SYMBOL(vsnprintf);
2379
2380/**
2381 * vscnprintf - Format a string and place it in a buffer
2382 * @buf: The buffer to place the result into
2383 * @size: The size of the buffer, including the trailing null space
2384 * @fmt: The format string to use
2385 * @args: Arguments for the format string
2386 *
2387 * The return value is the number of characters which have been written into
2388 * the @buf not including the trailing '\0'. If @size is == 0 the function
2389 * returns 0.
2390 *
2391 * If you're not already dealing with a va_list consider using scnprintf().
2392 *
2393 * See the vsnprintf() documentation for format string extensions over C99.
2394 */
2395int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2396{
2397        int i;
2398
2399        i = vsnprintf(buf, size, fmt, args);
2400
2401        if (likely(i < size))
2402                return i;
2403        if (size != 0)
2404                return size - 1;
2405        return 0;
2406}
2407EXPORT_SYMBOL(vscnprintf);
2408
2409/**
2410 * snprintf - Format a string and place it in a buffer
2411 * @buf: The buffer to place the result into
2412 * @size: The size of the buffer, including the trailing null space
2413 * @fmt: The format string to use
2414 * @...: Arguments for the format string
2415 *
2416 * The return value is the number of characters which would be
2417 * generated for the given input, excluding the trailing null,
2418 * as per ISO C99.  If the return is greater than or equal to
2419 * @size, the resulting string is truncated.
2420 *
2421 * See the vsnprintf() documentation for format string extensions over C99.
2422 */
2423int snprintf(char *buf, size_t size, const char *fmt, ...)
2424{
2425        va_list args;
2426        int i;
2427
2428        va_start(args, fmt);
2429        i = vsnprintf(buf, size, fmt, args);
2430        va_end(args);
2431
2432        return i;
2433}
2434EXPORT_SYMBOL(snprintf);
2435
2436/**
2437 * scnprintf - Format a string and place it in a buffer
2438 * @buf: The buffer to place the result into
2439 * @size: The size of the buffer, including the trailing null space
2440 * @fmt: The format string to use
2441 * @...: Arguments for the format string
2442 *
2443 * The return value is the number of characters written into @buf not including
2444 * the trailing '\0'. If @size is == 0 the function returns 0.
2445 */
2446
2447int scnprintf(char *buf, size_t size, const char *fmt, ...)
2448{
2449        va_list args;
2450        int i;
2451
2452        va_start(args, fmt);
2453        i = vscnprintf(buf, size, fmt, args);
2454        va_end(args);
2455
2456        return i;
2457}
2458EXPORT_SYMBOL(scnprintf);
2459
2460/**
2461 * vsprintf - Format a string and place it in a buffer
2462 * @buf: The buffer to place the result into
2463 * @fmt: The format string to use
2464 * @args: Arguments for the format string
2465 *
2466 * The function returns the number of characters written
2467 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2468 * buffer overflows.
2469 *
2470 * If you're not already dealing with a va_list consider using sprintf().
2471 *
2472 * See the vsnprintf() documentation for format string extensions over C99.
2473 */
2474int vsprintf(char *buf, const char *fmt, va_list args)
2475{
2476        return vsnprintf(buf, INT_MAX, fmt, args);
2477}
2478EXPORT_SYMBOL(vsprintf);
2479
2480/**
2481 * sprintf - Format a string and place it in a buffer
2482 * @buf: The buffer to place the result into
2483 * @fmt: The format string to use
2484 * @...: Arguments for the format string
2485 *
2486 * The function returns the number of characters written
2487 * into @buf. Use snprintf() or scnprintf() in order to avoid
2488 * buffer overflows.
2489 *
2490 * See the vsnprintf() documentation for format string extensions over C99.
2491 */
2492int sprintf(char *buf, const char *fmt, ...)
2493{
2494        va_list args;
2495        int i;
2496
2497        va_start(args, fmt);
2498        i = vsnprintf(buf, INT_MAX, fmt, args);
2499        va_end(args);
2500
2501        return i;
2502}
2503EXPORT_SYMBOL(sprintf);
2504
2505#ifdef CONFIG_BINARY_PRINTF
2506/*
2507 * bprintf service:
2508 * vbin_printf() - VA arguments to binary data
2509 * bstr_printf() - Binary data to text string
2510 */
2511
2512/**
2513 * vbin_printf - Parse a format string and place args' binary value in a buffer
2514 * @bin_buf: The buffer to place args' binary value
2515 * @size: The size of the buffer(by words(32bits), not characters)
2516 * @fmt: The format string to use
2517 * @args: Arguments for the format string
2518 *
2519 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2520 * is skipped.
2521 *
2522 * The return value is the number of words(32bits) which would be generated for
2523 * the given input.
2524 *
2525 * NOTE:
2526 * If the return value is greater than @size, the resulting bin_buf is NOT
2527 * valid for bstr_printf().
2528 */
2529int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2530{
2531        struct printf_spec spec = {0};
2532        char *str, *end;
2533        int width;
2534
2535        str = (char *)bin_buf;
2536        end = (char *)(bin_buf + size);
2537
2538#define save_arg(type)                                                  \
2539({                                                                      \
2540        unsigned long long value;                                       \
2541        if (sizeof(type) == 8) {                                        \
2542                unsigned long long val8;                                \
2543                str = PTR_ALIGN(str, sizeof(u32));                      \
2544                val8 = va_arg(args, unsigned long long);                \
2545                if (str + sizeof(type) <= end) {                        \
2546                        *(u32 *)str = *(u32 *)&val8;                    \
2547                        *(u32 *)(str + 4) = *((u32 *)&val8 + 1);        \
2548                }                                                       \
2549                value = val8;                                           \
2550        } else {                                                        \
2551                unsigned int val4;                                      \
2552                str = PTR_ALIGN(str, sizeof(type));                     \
2553                val4 = va_arg(args, int);                               \
2554                if (str + sizeof(type) <= end)                          \
2555                        *(typeof(type) *)str = (type)(long)val4;        \
2556                value = (unsigned long long)val4;                       \
2557        }                                                               \
2558        str += sizeof(type);                                            \
2559        value;                                                          \
2560})
2561
2562        while (*fmt) {
2563                int read = format_decode(fmt, &spec);
2564
2565                fmt += read;
2566
2567                switch (spec.type) {
2568                case FORMAT_TYPE_NONE:
2569                case FORMAT_TYPE_PERCENT_CHAR:
2570                        break;
2571                case FORMAT_TYPE_INVALID:
2572                        goto out;
2573
2574                case FORMAT_TYPE_WIDTH:
2575                case FORMAT_TYPE_PRECISION:
2576                        width = (int)save_arg(int);
2577                        /* Pointers may require the width */
2578                        if (*fmt == 'p')
2579                                set_field_width(&spec, width);
2580                        break;
2581
2582                case FORMAT_TYPE_CHAR:
2583                        save_arg(char);
2584                        break;
2585
2586                case FORMAT_TYPE_STR: {
2587                        const char *save_str = va_arg(args, char *);
2588                        size_t len;
2589
2590                        if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2591                                        || (unsigned long)save_str < PAGE_SIZE)
2592                                save_str = "(null)";
2593                        len = strlen(save_str) + 1;
2594                        if (str + len < end)
2595                                memcpy(str, save_str, len);
2596                        str += len;
2597                        break;
2598                }
2599
2600                case FORMAT_TYPE_PTR:
2601                        /* Dereferenced pointers must be done now */
2602                        switch (*fmt) {
2603                        /* Dereference of functions is still OK */
2604                        case 'S':
2605                        case 's':
2606                        case 'F':
2607                        case 'f':
2608                        case 'x':
2609                        case 'K':
2610                                save_arg(void *);
2611                                break;
2612                        default:
2613                                if (!isalnum(*fmt)) {
2614                                        save_arg(void *);
2615                                        break;
2616                                }
2617                                str = pointer(fmt, str, end, va_arg(args, void *),
2618                                              spec);
2619                                if (str + 1 < end)
2620                                        *str++ = '\0';
2621                                else
2622                                        end[-1] = '\0'; /* Must be nul terminated */
2623                        }
2624                        /* skip all alphanumeric pointer suffixes */
2625                        while (isalnum(*fmt))
2626                                fmt++;
2627                        break;
2628
2629                default:
2630                        switch (spec.type) {
2631
2632                        case FORMAT_TYPE_LONG_LONG:
2633                                save_arg(long long);
2634                                break;
2635                        case FORMAT_TYPE_ULONG:
2636                        case FORMAT_TYPE_LONG:
2637                                save_arg(unsigned long);
2638                                break;
2639                        case FORMAT_TYPE_SIZE_T:
2640                                save_arg(size_t);
2641                                break;
2642                        case FORMAT_TYPE_PTRDIFF:
2643                                save_arg(ptrdiff_t);
2644                                break;
2645                        case FORMAT_TYPE_UBYTE:
2646                        case FORMAT_TYPE_BYTE:
2647                                save_arg(char);
2648                                break;
2649                        case FORMAT_TYPE_USHORT:
2650                        case FORMAT_TYPE_SHORT:
2651                                save_arg(short);
2652                                break;
2653                        default:
2654                                save_arg(int);
2655                        }
2656                }
2657        }
2658
2659out:
2660        return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2661#undef save_arg
2662}
2663EXPORT_SYMBOL_GPL(vbin_printf);
2664
2665/**
2666 * bstr_printf - Format a string from binary arguments and place it in a buffer
2667 * @buf: The buffer to place the result into
2668 * @size: The size of the buffer, including the trailing null space
2669 * @fmt: The format string to use
2670 * @bin_buf: Binary arguments for the format string
2671 *
2672 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2673 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2674 * a binary buffer that generated by vbin_printf.
2675 *
2676 * The format follows C99 vsnprintf, but has some extensions:
2677 *  see vsnprintf comment for details.
2678 *
2679 * The return value is the number of characters which would
2680 * be generated for the given input, excluding the trailing
2681 * '\0', as per ISO C99. If you want to have the exact
2682 * number of characters written into @buf as return value
2683 * (not including the trailing '\0'), use vscnprintf(). If the
2684 * return is greater than or equal to @size, the resulting
2685 * string is truncated.
2686 */
2687int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2688{
2689        struct printf_spec spec = {0};
2690        char *str, *end;
2691        const char *args = (const char *)bin_buf;
2692
2693        if (WARN_ON_ONCE(size > INT_MAX))
2694                return 0;
2695
2696        str = buf;
2697        end = buf + size;
2698
2699#define get_arg(type)                                                   \
2700({                                                                      \
2701        typeof(type) value;                                             \
2702        if (sizeof(type) == 8) {                                        \
2703                args = PTR_ALIGN(args, sizeof(u32));                    \
2704                *(u32 *)&value = *(u32 *)args;                          \
2705                *((u32 *)&value + 1) = *(u32 *)(args + 4);              \
2706        } else {                                                        \
2707                args = PTR_ALIGN(args, sizeof(type));                   \
2708                value = *(typeof(type) *)args;                          \
2709        }                                                               \
2710        args += sizeof(type);                                           \
2711        value;                                                          \
2712})
2713
2714        /* Make sure end is always >= buf */
2715        if (end < buf) {
2716                end = ((void *)-1);
2717                size = end - buf;
2718        }
2719
2720        while (*fmt) {
2721                const char *old_fmt = fmt;
2722                int read = format_decode(fmt, &spec);
2723
2724                fmt += read;
2725
2726                switch (spec.type) {
2727                case FORMAT_TYPE_NONE: {
2728                        int copy = read;
2729                        if (str < end) {
2730                                if (copy > end - str)
2731                                        copy = end - str;
2732                                memcpy(str, old_fmt, copy);
2733                        }
2734                        str += read;
2735                        break;
2736                }
2737
2738                case FORMAT_TYPE_WIDTH:
2739                        set_field_width(&spec, get_arg(int));
2740                        break;
2741
2742                case FORMAT_TYPE_PRECISION:
2743                        set_precision(&spec, get_arg(int));
2744                        break;
2745
2746                case FORMAT_TYPE_CHAR: {
2747                        char c;
2748
2749                        if (!(spec.flags & LEFT)) {
2750                                while (--spec.field_width > 0) {
2751                                        if (str < end)
2752                                                *str = ' ';
2753                                        ++str;
2754                                }
2755                        }
2756                        c = (unsigned char) get_arg(char);
2757                        if (str < end)
2758                                *str = c;
2759                        ++str;
2760                        while (--spec.field_width > 0) {
2761                                if (str < end)
2762                                        *str = ' ';
2763                                ++str;
2764                        }
2765                        break;
2766                }
2767
2768                case FORMAT_TYPE_STR: {
2769                        const char *str_arg = args;
2770                        args += strlen(str_arg) + 1;
2771                        str = string(str, end, (char *)str_arg, spec);
2772                        break;
2773                }
2774
2775                case FORMAT_TYPE_PTR: {
2776                        bool process = false;
2777                        int copy, len;
2778                        /* Non function dereferences were already done */
2779                        switch (*fmt) {
2780                        case 'S':
2781                        case 's':
2782                        case 'F':
2783                        case 'f':
2784                        case 'x':
2785                        case 'K':
2786                                process = true;
2787                                break;
2788                        default:
2789                                if (!isalnum(*fmt)) {
2790                                        process = true;
2791                                        break;
2792                                }
2793                                /* Pointer dereference was already processed */
2794                                if (str < end) {
2795                                        len = copy = strlen(args);
2796                                        if (copy > end - str)
2797                                                copy = end - str;
2798                                        memcpy(str, args, copy);
2799                                        str += len;
2800                                        args += len + 1;
2801                                }
2802                        }
2803                        if (process)
2804                                str = pointer(fmt, str, end, get_arg(void *), spec);
2805
2806                        while (isalnum(*fmt))
2807                                fmt++;
2808                        break;
2809                }
2810
2811                case FORMAT_TYPE_PERCENT_CHAR:
2812                        if (str < end)
2813                                *str = '%';
2814                        ++str;
2815                        break;
2816
2817                case FORMAT_TYPE_INVALID:
2818                        goto out;
2819
2820                default: {
2821                        unsigned long long num;
2822
2823                        switch (spec.type) {
2824
2825                        case FORMAT_TYPE_LONG_LONG:
2826                                num = get_arg(long long);
2827                                break;
2828                        case FORMAT_TYPE_ULONG:
2829                        case FORMAT_TYPE_LONG:
2830                                num = get_arg(unsigned long);
2831                                break;
2832                        case FORMAT_TYPE_SIZE_T:
2833                                num = get_arg(size_t);
2834                                break;
2835                        case FORMAT_TYPE_PTRDIFF:
2836                                num = get_arg(ptrdiff_t);
2837                                break;
2838                        case FORMAT_TYPE_UBYTE:
2839                                num = get_arg(unsigned char);
2840                                break;
2841                        case FORMAT_TYPE_BYTE:
2842                                num = get_arg(signed char);
2843                                break;
2844                        case FORMAT_TYPE_USHORT:
2845                                num = get_arg(unsigned short);
2846                                break;
2847                        case FORMAT_TYPE_SHORT:
2848                                num = get_arg(short);
2849                                break;
2850                        case FORMAT_TYPE_UINT:
2851                                num = get_arg(unsigned int);
2852                                break;
2853                        default:
2854                                num = get_arg(int);
2855                        }
2856
2857                        str = number(str, end, num, spec);
2858                } /* default: */
2859                } /* switch(spec.type) */
2860        } /* while(*fmt) */
2861
2862out:
2863        if (size > 0) {
2864                if (str < end)
2865                        *str = '\0';
2866                else
2867                        end[-1] = '\0';
2868        }
2869
2870#undef get_arg
2871
2872        /* the trailing null byte doesn't count towards the total */
2873        return str - buf;
2874}
2875EXPORT_SYMBOL_GPL(bstr_printf);
2876
2877/**
2878 * bprintf - Parse a format string and place args' binary value in a buffer
2879 * @bin_buf: The buffer to place args' binary value
2880 * @size: The size of the buffer(by words(32bits), not characters)
2881 * @fmt: The format string to use
2882 * @...: Arguments for the format string
2883 *
2884 * The function returns the number of words(u32) written
2885 * into @bin_buf.
2886 */
2887int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2888{
2889        va_list args;
2890        int ret;
2891
2892        va_start(args, fmt);
2893        ret = vbin_printf(bin_buf, size, fmt, args);
2894        va_end(args);
2895
2896        return ret;
2897}
2898EXPORT_SYMBOL_GPL(bprintf);
2899
2900#endif /* CONFIG_BINARY_PRINTF */
2901
2902/**
2903 * vsscanf - Unformat a buffer into a list of arguments
2904 * @buf:        input buffer
2905 * @fmt:        format of buffer
2906 * @args:       arguments
2907 */
2908int vsscanf(const char *buf, const char *fmt, va_list args)
2909{
2910        const char *str = buf;
2911        char *next;
2912        char digit;
2913        int num = 0;
2914        u8 qualifier;
2915        unsigned int base;
2916        union {
2917                long long s;
2918                unsigned long long u;
2919        } val;
2920        s16 field_width;
2921        bool is_sign;
2922
2923        while (*fmt) {
2924                /* skip any white space in format */
2925                /* white space in format matchs any amount of
2926                 * white space, including none, in the input.
2927                 */
2928                if (isspace(*fmt)) {
2929                        fmt = skip_spaces(++fmt);
2930                        str = skip_spaces(str);
2931                }
2932
2933                /* anything that is not a conversion must match exactly */
2934                if (*fmt != '%' && *fmt) {
2935                        if (*fmt++ != *str++)
2936                                break;
2937                        continue;
2938                }
2939
2940                if (!*fmt)
2941                        break;
2942                ++fmt;
2943
2944                /* skip this conversion.
2945                 * advance both strings to next white space
2946                 */
2947                if (*fmt == '*') {
2948                        if (!*str)
2949                                break;
2950                        while (!isspace(*fmt) && *fmt != '%' && *fmt) {
2951                                /* '%*[' not yet supported, invalid format */
2952                                if (*fmt == '[')
2953                                        return num;
2954                                fmt++;
2955                        }
2956                        while (!isspace(*str) && *str)
2957                                str++;
2958                        continue;
2959                }
2960
2961                /* get field width */
2962                field_width = -1;
2963                if (isdigit(*fmt)) {
2964                        field_width = skip_atoi(&fmt);
2965                        if (field_width <= 0)
2966                                break;
2967                }
2968
2969                /* get conversion qualifier */
2970                qualifier = -1;
2971                if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2972                    *fmt == 'z') {
2973                        qualifier = *fmt++;
2974                        if (unlikely(qualifier == *fmt)) {
2975                                if (qualifier == 'h') {
2976                                        qualifier = 'H';
2977                                        fmt++;
2978                                } else if (qualifier == 'l') {
2979                                        qualifier = 'L';
2980                                        fmt++;
2981                                }
2982                        }
2983                }
2984
2985                if (!*fmt)
2986                        break;
2987
2988                if (*fmt == 'n') {
2989                        /* return number of characters read so far */
2990                        *va_arg(args, int *) = str - buf;
2991                        ++fmt;
2992                        continue;
2993                }
2994
2995                if (!*str)
2996                        break;
2997
2998                base = 10;
2999                is_sign = false;
3000
3001                switch (*fmt++) {
3002                case 'c':
3003                {
3004                        char *s = (char *)va_arg(args, char*);
3005                        if (field_width == -1)
3006                                field_width = 1;
3007                        do {
3008                                *s++ = *str++;
3009                        } while (--field_width > 0 && *str);
3010                        num++;
3011                }
3012                continue;
3013                case 's':
3014                {
3015                        char *s = (char *)va_arg(args, char *);
3016                        if (field_width == -1)
3017                                field_width = SHRT_MAX;
3018                        /* first, skip leading white space in buffer */
3019                        str = skip_spaces(str);
3020
3021                        /* now copy until next white space */
3022                        while (*str && !isspace(*str) && field_width--)
3023                                *s++ = *str++;
3024                        *s = '\0';
3025                        num++;
3026                }
3027                continue;
3028                /*
3029                 * Warning: This implementation of the '[' conversion specifier
3030                 * deviates from its glibc counterpart in the following ways:
3031                 * (1) It does NOT support ranges i.e. '-' is NOT a special
3032                 *     character
3033                 * (2) It cannot match the closing bracket ']' itself
3034                 * (3) A field width is required
3035                 * (4) '%*[' (discard matching input) is currently not supported
3036                 *
3037                 * Example usage:
3038                 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3039                 *              buf1, buf2, buf3);
3040                 * if (ret < 3)
3041                 *    // etc..
3042                 */
3043                case '[':
3044                {
3045                        char *s = (char *)va_arg(args, char *);
3046                        DECLARE_BITMAP(set, 256) = {0};
3047                        unsigned int len = 0;
3048                        bool negate = (*fmt == '^');
3049
3050                        /* field width is required */
3051                        if (field_width == -1)
3052                                return num;
3053
3054                        if (negate)
3055                                ++fmt;
3056
3057                        for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3058                                set_bit((u8)*fmt, set);
3059
3060                        /* no ']' or no character set found */
3061                        if (!*fmt || !len)
3062                                return num;
3063                        ++fmt;
3064
3065                        if (negate) {
3066                                bitmap_complement(set, set, 256);
3067                                /* exclude null '\0' byte */
3068                                clear_bit(0, set);
3069                        }
3070
3071                        /* match must be non-empty */
3072                        if (!test_bit((u8)*str, set))
3073                                return num;
3074
3075                        while (test_bit((u8)*str, set) && field_width--)
3076                                *s++ = *str++;
3077                        *s = '\0';
3078                        ++num;
3079                }
3080                continue;
3081                case 'o':
3082                        base = 8;
3083                        break;
3084                case 'x':
3085                case 'X':
3086                        base = 16;
3087                        break;
3088                case 'i':
3089                        base = 0;
3090                        /* fall through */
3091                case 'd':
3092                        is_sign = true;
3093                        /* fall through */
3094                case 'u':
3095                        break;
3096                case '%':
3097                        /* looking for '%' in str */
3098                        if (*str++ != '%')
3099                                return num;
3100                        continue;
3101                default:
3102                        /* invalid format; stop here */
3103                        return num;
3104                }
3105
3106                /* have some sort of integer conversion.
3107                 * first, skip white space in buffer.
3108                 */
3109                str = skip_spaces(str);
3110
3111                digit = *str;
3112                if (is_sign && digit == '-')
3113                        digit = *(str + 1);
3114
3115                if (!digit
3116                    || (base == 16 && !isxdigit(digit))
3117                    || (base == 10 && !isdigit(digit))
3118                    || (base == 8 && (!isdigit(digit) || digit > '7'))
3119                    || (base == 0 && !isdigit(digit)))
3120                        break;
3121
3122                if (is_sign)
3123                        val.s = qualifier != 'L' ?
3124                                simple_strtol(str, &next, base) :
3125                                simple_strtoll(str, &next, base);
3126                else
3127                        val.u = qualifier != 'L' ?
3128                                simple_strtoul(str, &next, base) :
3129                                simple_strtoull(str, &next, base);
3130
3131                if (field_width > 0 && next - str > field_width) {
3132                        if (base == 0)
3133                                _parse_integer_fixup_radix(str, &base);
3134                        while (next - str > field_width) {
3135                                if (is_sign)
3136                                        val.s = div_s64(val.s, base);
3137                                else
3138                                        val.u = div_u64(val.u, base);
3139                                --next;
3140                        }
3141                }
3142
3143                switch (qualifier) {
3144                case 'H':       /* that's 'hh' in format */
3145                        if (is_sign)
3146                                *va_arg(args, signed char *) = val.s;
3147                        else
3148                                *va_arg(args, unsigned char *) = val.u;
3149                        break;
3150                case 'h':
3151                        if (is_sign)
3152                                *va_arg(args, short *) = val.s;
3153                        else
3154                                *va_arg(args, unsigned short *) = val.u;
3155                        break;
3156                case 'l':
3157                        if (is_sign)
3158                                *va_arg(args, long *) = val.s;
3159                        else
3160                                *va_arg(args, unsigned long *) = val.u;
3161                        break;
3162                case 'L':
3163                        if (is_sign)
3164                                *va_arg(args, long long *) = val.s;
3165                        else
3166                                *va_arg(args, unsigned long long *) = val.u;
3167                        break;
3168                case 'z':
3169                        *va_arg(args, size_t *) = val.u;
3170                        break;
3171                default:
3172                        if (is_sign)
3173                                *va_arg(args, int *) = val.s;
3174                        else
3175                                *va_arg(args, unsigned int *) = val.u;
3176                        break;
3177                }
3178                num++;
3179
3180                if (!next)
3181                        break;
3182                str = next;
3183        }
3184
3185        return num;
3186}
3187EXPORT_SYMBOL(vsscanf);
3188
3189/**
3190 * sscanf - Unformat a buffer into a list of arguments
3191 * @buf:        input buffer
3192 * @fmt:        formatting of buffer
3193 * @...:        resulting arguments
3194 */
3195int sscanf(const char *buf, const char *fmt, ...)
3196{
3197        va_list args;
3198        int i;
3199
3200        va_start(args, fmt);
3201        i = vsscanf(buf, fmt, args);
3202        va_end(args);
3203
3204        return i;
3205}
3206EXPORT_SYMBOL(sscanf);
3207