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TOMOYO Linux Cross Reference
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 56  * This function is obsolete.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  */
 58 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
 59 {
 60         unsigned long long result;
 61         unsigned int rv;
 62 
 63         cp = _parse_integer_fixup_radix(cp, &base);
 64         rv = _parse_integer(cp, base, &result);
 65         /* FIXME */
 66         cp += (rv & ~KSTRTOX_OVERFLOW);
 67 
 68         if (endp)
 69                 *endp = (char *)cp;
 70 
 71         return result;
 72 }
 73 EXPORT_SYMBOL(simple_strtoull);
 74 
 75 /**
 76  * simple_strtoul - convert a string to an unsigned long
 77  * @cp: The start of the string
 78  * @endp: A pointer to the end of the parsed string will be placed here
 79  * @base: The number base to use
 80  *
 81  * This function is obsolete. Please use kstrtoul instead.
 82  */
 83 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
 84 {
 85         return simple_strtoull(cp, endp, base);
 86 }
 87 EXPORT_SYMBOL(simple_strtoul);
 88 
 89 /**
 90  * simple_strtol - convert a string to a signed long
 91  * @cp: The start of the string
 92  * @endp: A pointer to the end of the parsed string will be placed here
 93  * @base: The number base to use
 94  *
 95  * This function is obsolete. Please use kstrtol instead.
 96  */
 97 long simple_strtol(const char *cp, char **endp, unsigned int base)
 98 {
 99         if (*cp == '-')
100                 return -simple_strtoul(cp + 1, endp, base);
101 
102         return simple_strtoul(cp, endp, base);
103 }
104 EXPORT_SYMBOL(simple_strtol);
105 
106 /**
107  * simple_strtoll - convert a string to a signed long long
108  * @cp: The start of the string
109  * @endp: A pointer to the end of the parsed string will be placed here
110  * @base: The number base to use
111  *
112  * This function is obsolete. Please use kstrtoll instead.
113  */
114 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
115 {
116         if (*cp == '-')
117                 return -simple_strtoull(cp + 1, endp, base);
118 
119         return simple_strtoull(cp, endp, base);
120 }
121 EXPORT_SYMBOL(simple_strtoll);
122 
123 static noinline_for_stack
124 int skip_atoi(const char **s)
125 {
126         int i = 0;
127 
128         do {
129                 i = i*10 + *((*s)++) - '';
130         } while (isdigit(**s));
131 
132         return i;
133 }
134 
135 /*
136  * Decimal conversion is by far the most typical, and is used for
137  * /proc and /sys data. This directly impacts e.g. top performance
138  * with many processes running. We optimize it for speed by emitting
139  * two characters at a time, using a 200 byte lookup table. This
140  * roughly halves the number of multiplications compared to computing
141  * the digits one at a time. Implementation strongly inspired by the
142  * previous version, which in turn used ideas described at
143  * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
144  * from the author, Douglas W. Jones).
145  *
146  * It turns out there is precisely one 26 bit fixed-point
147  * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
148  * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
149  * range happens to be somewhat larger (x <= 1073741898), but that's
150  * irrelevant for our purpose.
151  *
152  * For dividing a number in the range [10^4, 10^6-1] by 100, we still
153  * need a 32x32->64 bit multiply, so we simply use the same constant.
154  *
155  * For dividing a number in the range [100, 10^4-1] by 100, there are
156  * several options. The simplest is (x * 0x147b) >> 19, which is valid
157  * for all x <= 43698.
158  */
159 
160 static const u16 decpair[100] = {
161 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
162         _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
163         _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
164         _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
165         _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
166         _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
167         _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
168         _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
169         _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
170         _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
171         _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
172 #undef _
173 };
174 
175 /*
176  * This will print a single '' even if r == 0, since we would
177  * immediately jump to out_r where two 0s would be written but only
178  * one of them accounted for in buf. This is needed by ip4_string
179  * below. All other callers pass a non-zero value of r.
180 */
181 static noinline_for_stack
182 char *put_dec_trunc8(char *buf, unsigned r)
183 {
184         unsigned q;
185 
186         /* 1 <= r < 10^8 */
187         if (r < 100)
188                 goto out_r;
189 
190         /* 100 <= r < 10^8 */
191         q = (r * (u64)0x28f5c29) >> 32;
192         *((u16 *)buf) = decpair[r - 100*q];
193         buf += 2;
194 
195         /* 1 <= q < 10^6 */
196         if (q < 100)
197                 goto out_q;
198 
199         /*  100 <= q < 10^6 */
200         r = (q * (u64)0x28f5c29) >> 32;
201         *((u16 *)buf) = decpair[q - 100*r];
202         buf += 2;
203 
204         /* 1 <= r < 10^4 */
205         if (r < 100)
206                 goto out_r;
207 
208         /* 100 <= r < 10^4 */
209         q = (r * 0x147b) >> 19;
210         *((u16 *)buf) = decpair[r - 100*q];
211         buf += 2;
212 out_q:
213         /* 1 <= q < 100 */
214         r = q;
215 out_r:
216         /* 1 <= r < 100 */
217         *((u16 *)buf) = decpair[r];
218         buf += r < 10 ? 1 : 2;
219         return buf;
220 }
221 
222 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
223 static noinline_for_stack
224 char *put_dec_full8(char *buf, unsigned r)
225 {
226         unsigned q;
227 
228         /* 0 <= r < 10^8 */
229         q = (r * (u64)0x28f5c29) >> 32;
230         *((u16 *)buf) = decpair[r - 100*q];
231         buf += 2;
232 
233         /* 0 <= q < 10^6 */
234         r = (q * (u64)0x28f5c29) >> 32;
235         *((u16 *)buf) = decpair[q - 100*r];
236         buf += 2;
237 
238         /* 0 <= r < 10^4 */
239         q = (r * 0x147b) >> 19;
240         *((u16 *)buf) = decpair[r - 100*q];
241         buf += 2;
242 
243         /* 0 <= q < 100 */
244         *((u16 *)buf) = decpair[q];
245         buf += 2;
246         return buf;
247 }
248 
249 static noinline_for_stack
250 char *put_dec(char *buf, unsigned long long n)
251 {
252         if (n >= 100*1000*1000)
253                 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
254         /* 1 <= n <= 1.6e11 */
255         if (n >= 100*1000*1000)
256                 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
257         /* 1 <= n < 1e8 */
258         return put_dec_trunc8(buf, n);
259 }
260 
261 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
262 
263 static void
264 put_dec_full4(char *buf, unsigned r)
265 {
266         unsigned q;
267 
268         /* 0 <= r < 10^4 */
269         q = (r * 0x147b) >> 19;
270         *((u16 *)buf) = decpair[r - 100*q];
271         buf += 2;
272         /* 0 <= q < 100 */
273         *((u16 *)buf) = decpair[q];
274 }
275 
276 /*
277  * Call put_dec_full4 on x % 10000, return x / 10000.
278  * The approximation x/10000 == (x * 0x346DC5D7) >> 43
279  * holds for all x < 1,128,869,999.  The largest value this
280  * helper will ever be asked to convert is 1,125,520,955.
281  * (second call in the put_dec code, assuming n is all-ones).
282  */
283 static noinline_for_stack
284 unsigned put_dec_helper4(char *buf, unsigned x)
285 {
286         uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
287 
288         put_dec_full4(buf, x - q * 10000);
289         return q;
290 }
291 
292 /* Based on code by Douglas W. Jones found at
293  * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
294  * (with permission from the author).
295  * Performs no 64-bit division and hence should be fast on 32-bit machines.
296  */
297 static
298 char *put_dec(char *buf, unsigned long long n)
299 {
300         uint32_t d3, d2, d1, q, h;
301 
302         if (n < 100*1000*1000)
303                 return put_dec_trunc8(buf, n);
304 
305         d1  = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
306         h   = (n >> 32);
307         d2  = (h      ) & 0xffff;
308         d3  = (h >> 16); /* implicit "& 0xffff" */
309 
310         /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
311              = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
312         q   = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
313         q = put_dec_helper4(buf, q);
314 
315         q += 7671 * d3 + 9496 * d2 + 6 * d1;
316         q = put_dec_helper4(buf+4, q);
317 
318         q += 4749 * d3 + 42 * d2;
319         q = put_dec_helper4(buf+8, q);
320 
321         q += 281 * d3;
322         buf += 12;
323         if (q)
324                 buf = put_dec_trunc8(buf, q);
325         else while (buf[-1] == '')
326                 --buf;
327 
328         return buf;
329 }
330 
331 #endif
332 
333 /*
334  * Convert passed number to decimal string.
335  * Returns the length of string.  On buffer overflow, returns 0.
336  *
337  * If speed is not important, use snprintf(). It's easy to read the code.
338  */
339 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
340 {
341         /* put_dec requires 2-byte alignment of the buffer. */
342         char tmp[sizeof(num) * 3] __aligned(2);
343         int idx, len;
344 
345         /* put_dec() may work incorrectly for num = 0 (generate "", not "") */
346         if (num <= 9) {
347                 tmp[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 == '' - ' ' */
375 #define SMALL   32              /* use lowercase in hex (must be 32 == 0x20) */
376 #define SPECIAL 64              /* prefix hex with "0x", octal with "" */
377 
378 enum format_type {
379         FORMAT_TYPE_NONE, /* Just a string part */
380         FORMAT_TYPE_WIDTH,
381         FORMAT_TYPE_PRECISION,
382         FORMAT_TYPE_CHAR,
383         FORMAT_TYPE_STR,
384         FORMAT_TYPE_PTR,
385         FORMAT_TYPE_PERCENT_CHAR,
386         FORMAT_TYPE_INVALID,
387         FORMAT_TYPE_LONG_LONG,
388         FORMAT_TYPE_ULONG,
389         FORMAT_TYPE_LONG,
390         FORMAT_TYPE_UBYTE,
391         FORMAT_TYPE_BYTE,
392         FORMAT_TYPE_USHORT,
393         FORMAT_TYPE_SHORT,
394         FORMAT_TYPE_UINT,
395         FORMAT_TYPE_INT,
396         FORMAT_TYPE_SIZE_T,
397         FORMAT_TYPE_PTRDIFF
398 };
399 
400 struct printf_spec {
401         unsigned int    type:8;         /* format_type enum */
402         signed int      field_width:24; /* width of output field */
403         unsigned int    flags:8;        /* flags to number() */
404         unsigned int    base:8;         /* number base, 8, 10 or 16 only */
405         signed int      precision:16;   /* # of digits/chars */
406 } __packed;
407 #define FIELD_WIDTH_MAX ((1 << 23) - 1)
408 #define PRECISION_MAX ((1 << 15) - 1)
409 
410 static noinline_for_stack
411 char *number(char *buf, char *end, unsigned long long num,
412              struct printf_spec spec)
413 {
414         /* put_dec requires 2-byte alignment of the buffer. */
415         char tmp[3 * sizeof(num)] __aligned(2);
416         char sign;
417         char locase;
418         int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
419         int i;
420         bool is_zero = num == 0LL;
421         int field_width = spec.field_width;
422         int precision = spec.precision;
423 
424         BUILD_BUG_ON(sizeof(struct printf_spec) != 8);
425 
426         /* locase = 0 or 0x20. ORing digits or letters with 'locase'
427          * produces same digits or (maybe lowercased) letters */
428         locase = (spec.flags & SMALL);
429         if (spec.flags & LEFT)
430                 spec.flags &= ~ZEROPAD;
431         sign = 0;
432         if (spec.flags & SIGN) {
433                 if ((signed long long)num < 0) {
434                         sign = '-';
435                         num = -(signed long long)num;
436                         field_width--;
437                 } else if (spec.flags & PLUS) {
438                         sign = '+';
439                         field_width--;
440                 } else if (spec.flags & SPACE) {
441                         sign = ' ';
442                         field_width--;
443                 }
444         }
445         if (need_pfx) {
446                 if (spec.base == 16)
447                         field_width -= 2;
448                 else if (!is_zero)
449                         field_width--;
450         }
451 
452         /* generate full string in tmp[], in reverse order */
453         i = 0;
454         if (num < spec.base)
455                 tmp[i++] = hex_asc_upper[num] | locase;
456         else if (spec.base != 10) { /* 8 or 16 */
457                 int mask = spec.base - 1;
458                 int shift = 3;
459 
460                 if (spec.base == 16)
461                         shift = 4;
462                 do {
463                         tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
464                         num >>= shift;
465                 } while (num);
466         } else { /* base 10 */
467                 i = put_dec(tmp, num) - tmp;
468         }
469 
470         /* printing 100 using %2d gives "100", not "00" */
471         if (i > precision)
472                 precision = i;
473         /* leading space padding */
474         field_width -= precision;
475         if (!(spec.flags & (ZEROPAD | LEFT))) {
476                 while (--field_width >= 0) {
477                         if (buf < end)
478                                 *buf = ' ';
479                         ++buf;
480                 }
481         }
482         /* sign */
483         if (sign) {
484                 if (buf < end)
485                         *buf = sign;
486                 ++buf;
487         }
488         /* "0x" / "" prefix */
489         if (need_pfx) {
490                 if (spec.base == 16 || !is_zero) {
491                         if (buf < end)
492                                 *buf = '';
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 != '');
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 = '';
515                 ++buf;
516         }
517         /* actual digits of result */
518         while (--i >= 0) {
519                 if (buf < end)
520                         *buf = tmp[i];
521                 ++buf;
522         }
523         /* trailing space padding */
524         while (--field_width >= 0) {
525                 if (buf < end)
526                         *buf = ' ';
527                 ++buf;
528         }
529 
530         return buf;
531 }
532 
533 static noinline_for_stack
534 char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
535 {
536         struct printf_spec spec;
537 
538         spec.type = FORMAT_TYPE_PTR;
539         spec.field_width = 2 + 2 * size;        /* 0x + hex */
540         spec.flags = SPECIAL | SMALL | ZEROPAD;
541         spec.base = 16;
542         spec.precision = -1;
543 
544         return number(buf, end, num, spec);
545 }
546 
547 static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
548 {
549         size_t size;
550         if (buf >= end) /* nowhere to put anything */
551                 return;
552         size = end - buf;
553         if (size <= spaces) {
554                 memset(buf, ' ', size);
555                 return;
556         }
557         if (len) {
558                 if (len > size - spaces)
559                         len = size - spaces;
560                 memmove(buf + spaces, buf, len);
561         }
562         memset(buf, ' ', spaces);
563 }
564 
565 /*
566  * Handle field width padding for a string.
567  * @buf: current buffer position
568  * @n: length of string
569  * @end: end of output buffer
570  * @spec: for field width and flags
571  * Returns: new buffer position after padding.
572  */
573 static noinline_for_stack
574 char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
575 {
576         unsigned spaces;
577 
578         if (likely(n >= spec.field_width))
579                 return buf;
580         /* we want to pad the sucker */
581         spaces = spec.field_width - n;
582         if (!(spec.flags & LEFT)) {
583                 move_right(buf - n, end, n, spaces);
584                 return buf + spaces;
585         }
586         while (spaces--) {
587                 if (buf < end)
588                         *buf = ' ';
589                 ++buf;
590         }
591         return buf;
592 }
593 
594 static noinline_for_stack
595 char *string(char *buf, char *end, const char *s, struct printf_spec spec)
596 {
597         int len = 0;
598         size_t lim = spec.precision;
599 
600         if ((unsigned long)s < PAGE_SIZE)
601                 s = "(null)";
602 
603         while (lim--) {
604                 char c = *s++;
605                 if (!c)
606                         break;
607                 if (buf < end)
608                         *buf = c;
609                 ++buf;
610                 ++len;
611         }
612         return widen_string(buf, len, end, spec);
613 }
614 
615 static noinline_for_stack
616 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
617                   const char *fmt)
618 {
619         const char *array[4], *s;
620         const struct dentry *p;
621         int depth;
622         int i, n;
623 
624         switch (fmt[1]) {
625                 case '2': case '3': case '4':
626                         depth = fmt[1] - '';
627                         break;
628                 default:
629                         depth = 1;
630         }
631 
632         rcu_read_lock();
633         for (i = 0; i < depth; i++, d = p) {
634                 p = READ_ONCE(d->d_parent);
635                 array[i] = READ_ONCE(d->d_name.name);
636                 if (p == d) {
637                         if (i)
638                                 array[i] = "";
639                         i++;
640                         break;
641                 }
642         }
643         s = array[--i];
644         for (n = 0; n != spec.precision; n++, buf++) {
645                 char c = *s++;
646                 if (!c) {
647                         if (!i)
648                                 break;
649                         c = '/';
650                         s = array[--i];
651                 }
652                 if (buf < end)
653                         *buf = c;
654         }
655         rcu_read_unlock();
656         return widen_string(buf, n, end, spec);
657 }
658 
659 #ifdef CONFIG_BLOCK
660 static noinline_for_stack
661 char *bdev_name(char *buf, char *end, struct block_device *bdev,
662                 struct printf_spec spec, const char *fmt)
663 {
664         struct gendisk *hd = bdev->bd_disk;
665         
666         buf = string(buf, end, hd->disk_name, spec);
667         if (bdev->bd_part->partno) {
668                 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
669                         if (buf < end)
670                                 *buf = 'p';
671                         buf++;
672                 }
673                 buf = number(buf, end, bdev->bd_part->partno, spec);
674         }
675         return buf;
676 }
677 #endif
678 
679 static noinline_for_stack
680 char *symbol_string(char *buf, char *end, void *ptr,
681                     struct printf_spec spec, const char *fmt)
682 {
683         unsigned long value;
684 #ifdef CONFIG_KALLSYMS
685         char sym[KSYM_SYMBOL_LEN];
686 #endif
687 
688         if (fmt[1] == 'R')
689                 ptr = __builtin_extract_return_addr(ptr);
690         value = (unsigned long)ptr;
691 
692 #ifdef CONFIG_KALLSYMS
693         if (*fmt == 'B')
694                 sprint_backtrace(sym, value);
695         else if (*fmt != 'f' && *fmt != 's')
696                 sprint_symbol(sym, value);
697         else
698                 sprint_symbol_no_offset(sym, value);
699 
700         return string(buf, end, sym, spec);
701 #else
702         return special_hex_number(buf, end, value, sizeof(void *));
703 #endif
704 }
705 
706 static noinline_for_stack
707 char *resource_string(char *buf, char *end, struct resource *res,
708                       struct printf_spec spec, const char *fmt)
709 {
710 #ifndef IO_RSRC_PRINTK_SIZE
711 #define IO_RSRC_PRINTK_SIZE     6
712 #endif
713 
714 #ifndef MEM_RSRC_PRINTK_SIZE
715 #define MEM_RSRC_PRINTK_SIZE    10
716 #endif
717         static const struct printf_spec io_spec = {
718                 .base = 16,
719                 .field_width = IO_RSRC_PRINTK_SIZE,
720                 .precision = -1,
721                 .flags = SPECIAL | SMALL | ZEROPAD,
722         };
723         static const struct printf_spec mem_spec = {
724                 .base = 16,
725                 .field_width = MEM_RSRC_PRINTK_SIZE,
726                 .precision = -1,
727                 .flags = SPECIAL | SMALL | ZEROPAD,
728         };
729         static const struct printf_spec bus_spec = {
730                 .base = 16,
731                 .field_width = 2,
732                 .precision = -1,
733                 .flags = SMALL | ZEROPAD,
734         };
735         static const struct printf_spec dec_spec = {
736                 .base = 10,
737                 .precision = -1,
738                 .flags = 0,
739         };
740         static const struct printf_spec str_spec = {
741                 .field_width = -1,
742                 .precision = 10,
743                 .flags = LEFT,
744         };
745         static const struct printf_spec flag_spec = {
746                 .base = 16,
747                 .precision = -1,
748                 .flags = SPECIAL | SMALL,
749         };
750 
751         /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
752          * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
753 #define RSRC_BUF_SIZE           ((2 * sizeof(resource_size_t)) + 4)
754 #define FLAG_BUF_SIZE           (2 * sizeof(res->flags))
755 #define DECODED_BUF_SIZE        sizeof("[mem - 64bit pref window disabled]")
756 #define RAW_BUF_SIZE            sizeof("[mem - flags 0x]")
757         char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
758                      2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
759 
760         char *p = sym, *pend = sym + sizeof(sym);
761         int decode = (fmt[0] == 'R') ? 1 : 0;
762         const struct printf_spec *specp;
763 
764         *p++ = '[';
765         if (res->flags & IORESOURCE_IO) {
766                 p = string(p, pend, "io  ", str_spec);
767                 specp = &io_spec;
768         } else if (res->flags & IORESOURCE_MEM) {
769                 p = string(p, pend, "mem ", str_spec);
770                 specp = &mem_spec;
771         } else if (res->flags & IORESOURCE_IRQ) {
772                 p = string(p, pend, "irq ", str_spec);
773                 specp = &dec_spec;
774         } else if (res->flags & IORESOURCE_DMA) {
775                 p = string(p, pend, "dma ", str_spec);
776                 specp = &dec_spec;
777         } else if (res->flags & IORESOURCE_BUS) {
778                 p = string(p, pend, "bus ", str_spec);
779                 specp = &bus_spec;
780         } else {
781                 p = string(p, pend, "??? ", str_spec);
782                 specp = &mem_spec;
783                 decode = 0;
784         }
785         if (decode && res->flags & IORESOURCE_UNSET) {
786                 p = string(p, pend, "size ", str_spec);
787                 p = number(p, pend, resource_size(res), *specp);
788         } else {
789                 p = number(p, pend, res->start, *specp);
790                 if (res->start != res->end) {
791                         *p++ = '-';
792                         p = number(p, pend, res->end, *specp);
793                 }
794         }
795         if (decode) {
796                 if (res->flags & IORESOURCE_MEM_64)
797                         p = string(p, pend, " 64bit", str_spec);
798                 if (res->flags & IORESOURCE_PREFETCH)
799                         p = string(p, pend, " pref", str_spec);
800                 if (res->flags & IORESOURCE_WINDOW)
801                         p = string(p, pend, " window", str_spec);
802                 if (res->flags & IORESOURCE_DISABLED)
803                         p = string(p, pend, " disabled", str_spec);
804         } else {
805                 p = string(p, pend, " flags ", str_spec);
806                 p = number(p, pend, res->flags, flag_spec);
807         }
808         *p++ = ']';
809         *p = '\0';
810 
811         return string(buf, end, sym, spec);
812 }
813 
814 static noinline_for_stack
815 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
816                  const char *fmt)
817 {
818         int i, len = 1;         /* if we pass '%ph[CDN]', field width remains
819                                    negative value, fallback to the default */
820         char separator;
821 
822         if (spec.field_width == 0)
823                 /* nothing to print */
824                 return buf;
825 
826         if (ZERO_OR_NULL_PTR(addr))
827                 /* NULL pointer */
828                 return string(buf, end, NULL, spec);
829 
830         switch (fmt[1]) {
831         case 'C':
832                 separator = ':';
833                 break;
834         case 'D':
835                 separator = '-';
836                 break;
837         case 'N':
838                 separator = 0;
839                 break;
840         default:
841                 separator = ' ';
842                 break;
843         }
844 
845         if (spec.field_width > 0)
846                 len = min_t(int, spec.field_width, 64);
847 
848         for (i = 0; i < len; ++i) {
849                 if (buf < end)
850                         *buf = hex_asc_hi(addr[i]);
851                 ++buf;
852                 if (buf < end)
853                         *buf = hex_asc_lo(addr[i]);
854                 ++buf;
855 
856                 if (separator && i != len - 1) {
857                         if (buf < end)
858                                 *buf = separator;
859                         ++buf;
860                 }
861         }
862 
863         return buf;
864 }
865 
866 static noinline_for_stack
867 char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
868                     struct printf_spec spec, const char *fmt)
869 {
870         const int CHUNKSZ = 32;
871         int nr_bits = max_t(int, spec.field_width, 0);
872         int i, chunksz;
873         bool first = true;
874 
875         /* reused to print numbers */
876         spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
877 
878         chunksz = nr_bits & (CHUNKSZ - 1);
879         if (chunksz == 0)
880                 chunksz = CHUNKSZ;
881 
882         i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
883         for (; i >= 0; i -= CHUNKSZ) {
884                 u32 chunkmask, val;
885                 int word, bit;
886 
887                 chunkmask = ((1ULL << chunksz) - 1);
888                 word = i / BITS_PER_LONG;
889                 bit = i % BITS_PER_LONG;
890                 val = (bitmap[word] >> bit) & chunkmask;
891 
892                 if (!first) {
893                         if (buf < end)
894                                 *buf = ',';
895                         buf++;
896                 }
897                 first = false;
898 
899                 spec.field_width = DIV_ROUND_UP(chunksz, 4);
900                 buf = number(buf, end, val, spec);
901 
902                 chunksz = CHUNKSZ;
903         }
904         return buf;
905 }
906 
907 static noinline_for_stack
908 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
909                          struct printf_spec spec, const char *fmt)
910 {
911         int nr_bits = max_t(int, spec.field_width, 0);
912         /* current bit is 'cur', most recently seen range is [rbot, rtop] */
913         int cur, rbot, rtop;
914         bool first = true;
915 
916         /* reused to print numbers */
917         spec = (struct printf_spec){ .base = 10 };
918 
919         rbot = cur = find_first_bit(bitmap, nr_bits);
920         while (cur < nr_bits) {
921                 rtop = cur;
922                 cur = find_next_bit(bitmap, nr_bits, cur + 1);
923                 if (cur < nr_bits && cur <= rtop + 1)
924                         continue;
925 
926                 if (!first) {
927                         if (buf < end)
928                                 *buf = ',';
929                         buf++;
930                 }
931                 first = false;
932 
933                 buf = number(buf, end, rbot, spec);
934                 if (rbot < rtop) {
935                         if (buf < end)
936                                 *buf = '-';
937                         buf++;
938 
939                         buf = number(buf, end, rtop, spec);
940                 }
941 
942                 rbot = cur;
943         }
944         return buf;
945 }
946 
947 static noinline_for_stack
948 char *mac_address_string(char *buf, char *end, u8 *addr,
949                          struct printf_spec spec, const char *fmt)
950 {
951         char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
952         char *p = mac_addr;
953         int i;
954         char separator;
955         bool reversed = false;
956 
957         switch (fmt[1]) {
958         case 'F':
959                 separator = '-';
960                 break;
961 
962         case 'R':
963                 reversed = true;
964                 /* fall through */
965 
966         default:
967                 separator = ':';
968                 break;
969         }
970 
971         for (i = 0; i < 6; i++) {
972                 if (reversed)
973                         p = hex_byte_pack(p, addr[5 - i]);
974                 else
975                         p = hex_byte_pack(p, addr[i]);
976 
977                 if (fmt[0] == 'M' && i != 5)
978                         *p++ = separator;
979         }
980         *p = '\0';
981 
982         return string(buf, end, mac_addr, spec);
983 }
984 
985 static noinline_for_stack
986 char *ip4_string(char *p, const u8 *addr, const char *fmt)
987 {
988         int i;
989         bool leading_zeros = (fmt[0] == 'i');
990         int index;
991         int step;
992 
993         switch (fmt[2]) {
994         case 'h':
995 #ifdef __BIG_ENDIAN
996                 index = 0;
997                 step = 1;
998 #else
999                 index = 3;
1000                 step = -1;
1001 #endif
1002                 break;
1003         case 'l':
1004                 index = 3;
1005                 step = -1;
1006                 break;
1007         case 'n':
1008         case 'b':
1009         default:
1010                 index = 0;
1011                 step = 1;
1012                 break;
1013         }
1014         for (i = 0; i < 4; i++) {
1015                 char temp[4] __aligned(2);      /* hold each IP quad in reverse order */
1016                 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1017                 if (leading_zeros) {
1018                         if (digits < 3)
1019                                 *p++ = '';
1020                         if (digits < 2)
1021                                 *p++ = '';
1022                 }
1023                 /* reverse the digits in the quad */
1024                 while (digits--)
1025                         *p++ = temp[digits];
1026                 if (i < 3)
1027                         *p++ = '.';
1028                 index += step;
1029         }
1030         *p = '\0';
1031 
1032         return p;
1033 }
1034 
1035 static noinline_for_stack
1036 char *ip6_compressed_string(char *p, const char *addr)
1037 {
1038         int i, j, range;
1039         unsigned char zerolength[8];
1040         int longest = 1;
1041         int colonpos = -1;
1042         u16 word;
1043         u8 hi, lo;
1044         bool needcolon = false;
1045         bool useIPv4;
1046         struct in6_addr in6;
1047 
1048         memcpy(&in6, addr, sizeof(struct in6_addr));
1049 
1050         useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1051 
1052         memset(zerolength, 0, sizeof(zerolength));
1053 
1054         if (useIPv4)
1055                 range = 6;
1056         else
1057                 range = 8;
1058 
1059         /* find position of longest 0 run */
1060         for (i = 0; i < range; i++) {
1061                 for (j = i; j < range; j++) {
1062                         if (in6.s6_addr16[j] != 0)
1063                                 break;
1064                         zerolength[i]++;
1065                 }
1066         }
1067         for (i = 0; i < range; i++) {
1068                 if (zerolength[i] > longest) {
1069                         longest = zerolength[i];
1070                         colonpos = i;
1071                 }
1072         }
1073         if (longest == 1)               /* don't compress a single 0 */
1074                 colonpos = -1;
1075 
1076         /* emit address */
1077         for (i = 0; i < range; i++) {
1078                 if (i == colonpos) {
1079                         if (needcolon || i == 0)
1080                                 *p++ = ':';
1081                         *p++ = ':';
1082                         needcolon = false;
1083                         i += longest - 1;
1084                         continue;
1085                 }
1086                 if (needcolon) {
1087                         *p++ = ':';
1088                         needcolon = false;
1089                 }
1090                 /* hex u16 without leading 0s */
1091                 word = ntohs(in6.s6_addr16[i]);
1092                 hi = word >> 8;
1093                 lo = word & 0xff;
1094                 if (hi) {
1095                         if (hi > 0x0f)
1096                                 p = hex_byte_pack(p, hi);
1097                         else
1098                                 *p++ = hex_asc_lo(hi);
1099                         p = hex_byte_pack(p, lo);
1100                 }
1101                 else if (lo > 0x0f)
1102                         p = hex_byte_pack(p, lo);
1103                 else
1104                         *p++ = hex_asc_lo(lo);
1105                 needcolon = true;
1106         }
1107 
1108         if (useIPv4) {
1109                 if (needcolon)
1110                         *p++ = ':';
1111                 p = ip4_string(p, &in6.s6_addr[12], "I4");
1112         }
1113         *p = '\0';
1114 
1115         return p;
1116 }
1117 
1118 static noinline_for_stack
1119 char *ip6_string(char *p, const char *addr, const char *fmt)
1120 {
1121         int i;
1122 
1123         for (i = 0; i < 8; i++) {
1124                 p = hex_byte_pack(p, *addr++);
1125                 p = hex_byte_pack(p, *addr++);
1126                 if (fmt[0] == 'I' && i != 7)
1127                         *p++ = ':';
1128         }
1129         *p = '\0';
1130 
1131         return p;
1132 }
1133 
1134 static noinline_for_stack
1135 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1136                       struct printf_spec spec, const char *fmt)
1137 {
1138         char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1139 
1140         if (fmt[0] == 'I' && fmt[2] == 'c')
1141                 ip6_compressed_string(ip6_addr, addr);
1142         else
1143                 ip6_string(ip6_addr, addr, fmt);
1144 
1145         return string(buf, end, ip6_addr, spec);
1146 }
1147 
1148 static noinline_for_stack
1149 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1150                       struct printf_spec spec, const char *fmt)
1151 {
1152         char ip4_addr[sizeof("255.255.255.255")];
1153 
1154         ip4_string(ip4_addr, addr, fmt);
1155 
1156         return string(buf, end, ip4_addr, spec);
1157 }
1158 
1159 static noinline_for_stack
1160 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1161                          struct printf_spec spec, const char *fmt)
1162 {
1163         bool have_p = false, have_s = false, have_f = false, have_c = false;
1164         char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1165                       sizeof(":12345") + sizeof("/123456789") +
1166                       sizeof("%1234567890")];
1167         char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1168         const u8 *addr = (const u8 *) &sa->sin6_addr;
1169         char fmt6[2] = { fmt[0], '6' };
1170         u8 off = 0;
1171 
1172         fmt++;
1173         while (isalpha(*++fmt)) {
1174                 switch (*fmt) {
1175                 case 'p':
1176                         have_p = true;
1177                         break;
1178                 case 'f':
1179                         have_f = true;
1180                         break;
1181                 case 's':
1182                         have_s = true;
1183                         break;
1184                 case 'c':
1185                         have_c = true;
1186                         break;
1187                 }
1188         }
1189 
1190         if (have_p || have_s || have_f) {
1191                 *p = '[';
1192                 off = 1;
1193         }
1194 
1195         if (fmt6[0] == 'I' && have_c)
1196                 p = ip6_compressed_string(ip6_addr + off, addr);
1197         else
1198                 p = ip6_string(ip6_addr + off, addr, fmt6);
1199 
1200         if (have_p || have_s || have_f)
1201                 *p++ = ']';
1202 
1203         if (have_p) {
1204                 *p++ = ':';
1205                 p = number(p, pend, ntohs(sa->sin6_port), spec);
1206         }
1207         if (have_f) {
1208                 *p++ = '/';
1209                 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1210                                           IPV6_FLOWINFO_MASK), spec);
1211         }
1212         if (have_s) {
1213                 *p++ = '%';
1214                 p = number(p, pend, sa->sin6_scope_id, spec);
1215         }
1216         *p = '\0';
1217 
1218         return string(buf, end, ip6_addr, spec);
1219 }
1220 
1221 static noinline_for_stack
1222 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1223                          struct printf_spec spec, const char *fmt)
1224 {
1225         bool have_p = false;
1226         char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1227         char *pend = ip4_addr + sizeof(ip4_addr);
1228         const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1229         char fmt4[3] = { fmt[0], '4', 0 };
1230 
1231         fmt++;
1232         while (isalpha(*++fmt)) {
1233                 switch (*fmt) {
1234                 case 'p':
1235                         have_p = true;
1236                         break;
1237                 case 'h':
1238                 case 'l':
1239                 case 'n':
1240                 case 'b':
1241                         fmt4[2] = *fmt;
1242                         break;
1243                 }
1244         }
1245 
1246         p = ip4_string(ip4_addr, addr, fmt4);
1247         if (have_p) {
1248                 *p++ = ':';
1249                 p = number(p, pend, ntohs(sa->sin_port), spec);
1250         }
1251         *p = '\0';
1252 
1253         return string(buf, end, ip4_addr, spec);
1254 }
1255 
1256 static noinline_for_stack
1257 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1258                      const char *fmt)
1259 {
1260         bool found = true;
1261         int count = 1;
1262         unsigned int flags = 0;
1263         int len;
1264 
1265         if (spec.field_width == 0)
1266                 return buf;                             /* nothing to print */
1267 
1268         if (ZERO_OR_NULL_PTR(addr))
1269                 return string(buf, end, NULL, spec);    /* NULL pointer */
1270 
1271 
1272         do {
1273                 switch (fmt[count++]) {
1274                 case 'a':
1275                         flags |= ESCAPE_ANY;
1276                         break;
1277                 case 'c':
1278                         flags |= ESCAPE_SPECIAL;
1279                         break;
1280                 case 'h':
1281                         flags |= ESCAPE_HEX;
1282                         break;
1283                 case 'n':
1284                         flags |= ESCAPE_NULL;
1285                         break;
1286                 case 'o':
1287                         flags |= ESCAPE_OCTAL;
1288                         break;
1289                 case 'p':
1290                         flags |= ESCAPE_NP;
1291                         break;
1292                 case 's':
1293                         flags |= ESCAPE_SPACE;
1294                         break;
1295                 default:
1296                         found = false;
1297                         break;
1298                 }
1299         } while (found);
1300 
1301         if (!flags)
1302                 flags = ESCAPE_ANY_NP;
1303 
1304         len = spec.field_width < 0 ? 1 : spec.field_width;
1305 
1306         /*
1307          * string_escape_mem() writes as many characters as it can to
1308          * the given buffer, and returns the total size of the output
1309          * had the buffer been big enough.
1310          */
1311         buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1312 
1313         return buf;
1314 }
1315 
1316 static noinline_for_stack
1317 char *uuid_string(char *buf, char *end, const u8 *addr,
1318                   struct printf_spec spec, const char *fmt)
1319 {
1320         char uuid[UUID_STRING_LEN + 1];
1321         char *p = uuid;
1322         int i;
1323         const u8 *index = uuid_index;
1324         bool uc = false;
1325 
1326         switch (*(++fmt)) {
1327         case 'L':
1328                 uc = true;              /* fall-through */
1329         case 'l':
1330                 index = guid_index;
1331                 break;
1332         case 'B':
1333                 uc = true;
1334                 break;
1335         }
1336 
1337         for (i = 0; i < 16; i++) {
1338                 if (uc)
1339                         p = hex_byte_pack_upper(p, addr[index[i]]);
1340                 else
1341                         p = hex_byte_pack(p, addr[index[i]]);
1342                 switch (i) {
1343                 case 3:
1344                 case 5:
1345                 case 7:
1346                 case 9:
1347                         *p++ = '-';
1348                         break;
1349                 }
1350         }
1351 
1352         *p = 0;
1353 
1354         return string(buf, end, uuid, spec);
1355 }
1356 
1357 int kptr_restrict __read_mostly;
1358 
1359 static noinline_for_stack
1360 char *restricted_pointer(char *buf, char *end, const void *ptr,
1361                          struct printf_spec spec)
1362 {
1363         spec.base = 16;
1364         spec.flags |= SMALL;
1365         if (spec.field_width == -1) {
1366                 spec.field_width = 2 * sizeof(ptr);
1367                 spec.flags |= ZEROPAD;
1368         }
1369 
1370         switch (kptr_restrict) {
1371         case 0:
1372                 /* Always print %pK values */
1373                 break;
1374         case 1: {
1375                 const struct cred *cred;
1376 
1377                 /*
1378                  * kptr_restrict==1 cannot be used in IRQ context
1379                  * because its test for CAP_SYSLOG would be meaningless.
1380                  */
1381                 if (in_irq() || in_serving_softirq() || in_nmi())
1382                         return string(buf, end, "pK-error", spec);
1383 
1384                 /*
1385                  * Only print the real pointer value if the current
1386                  * process has CAP_SYSLOG and is running with the
1387                  * same credentials it started with. This is because
1388                  * access to files is checked at open() time, but %pK
1389                  * checks permission at read() time. We don't want to
1390                  * leak pointer values if a binary opens a file using
1391                  * %pK and then elevates privileges before reading it.
1392                  */
1393                 cred = current_cred();
1394                 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
1395                     !uid_eq(cred->euid, cred->uid) ||
1396                     !gid_eq(cred->egid, cred->gid))
1397                         ptr = NULL;
1398                 break;
1399         }
1400         case 2:
1401         default:
1402                 /* Always print 0's for %pK */
1403                 ptr = NULL;
1404                 break;
1405         }
1406 
1407         return number(buf, end, (unsigned long)ptr, spec);
1408 }
1409 
1410 static noinline_for_stack
1411 char *netdev_bits(char *buf, char *end, const void *addr, const char *fmt)
1412 {
1413         unsigned long long num;
1414         int size;
1415 
1416         switch (fmt[1]) {
1417         case 'F':
1418                 num = *(const netdev_features_t *)addr;
1419                 size = sizeof(netdev_features_t);
1420                 break;
1421         default:
1422                 num = (unsigned long)addr;
1423                 size = sizeof(unsigned long);
1424                 break;
1425         }
1426 
1427         return special_hex_number(buf, end, num, size);
1428 }
1429 
1430 static noinline_for_stack
1431 char *address_val(char *buf, char *end, const void *addr, const char *fmt)
1432 {
1433         unsigned long long num;
1434         int size;
1435 
1436         switch (fmt[1]) {
1437         case 'd':
1438                 num = *(const dma_addr_t *)addr;
1439                 size = sizeof(dma_addr_t);
1440                 break;
1441         case 'p':
1442         default:
1443                 num = *(const phys_addr_t *)addr;
1444                 size = sizeof(phys_addr_t);
1445                 break;
1446         }
1447 
1448         return special_hex_number(buf, end, num, size);
1449 }
1450 
1451 static noinline_for_stack
1452 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1453             const char *fmt)
1454 {
1455         if (!IS_ENABLED(CONFIG_HAVE_CLK) || !clk)
1456                 return string(buf, end, NULL, spec);
1457 
1458         switch (fmt[1]) {
1459         case 'r':
1460                 return number(buf, end, clk_get_rate(clk), spec);
1461 
1462         case 'n':
1463         default:
1464 #ifdef CONFIG_COMMON_CLK
1465                 return string(buf, end, __clk_get_name(clk), spec);
1466 #else
1467                 return special_hex_number(buf, end, (unsigned long)clk, sizeof(unsigned long));
1468 #endif
1469         }
1470 }
1471 
1472 static
1473 char *format_flags(char *buf, char *end, unsigned long flags,
1474                                         const struct trace_print_flags *names)
1475 {
1476         unsigned long mask;
1477         const struct printf_spec strspec = {
1478                 .field_width = -1,
1479                 .precision = -1,
1480         };
1481         const struct printf_spec numspec = {
1482                 .flags = SPECIAL|SMALL,
1483                 .field_width = -1,
1484                 .precision = -1,
1485                 .base = 16,
1486         };
1487 
1488         for ( ; flags && names->name; names++) {
1489                 mask = names->mask;
1490                 if ((flags & mask) != mask)
1491                         continue;
1492 
1493                 buf = string(buf, end, names->name, strspec);
1494 
1495                 flags &= ~mask;
1496                 if (flags) {
1497                         if (buf < end)
1498                                 *buf = '|';
1499                         buf++;
1500                 }
1501         }
1502 
1503         if (flags)
1504                 buf = number(buf, end, flags, numspec);
1505 
1506         return buf;
1507 }
1508 
1509 static noinline_for_stack
1510 char *flags_string(char *buf, char *end, void *flags_ptr, const char *fmt)
1511 {
1512         unsigned long flags;
1513         const struct trace_print_flags *names;
1514 
1515         switch (fmt[1]) {
1516         case 'p':
1517                 flags = *(unsigned long *)flags_ptr;
1518                 /* Remove zone id */
1519                 flags &= (1UL << NR_PAGEFLAGS) - 1;
1520                 names = pageflag_names;
1521                 break;
1522         case 'v':
1523                 flags = *(unsigned long *)flags_ptr;
1524                 names = vmaflag_names;
1525                 break;
1526         case 'g':
1527                 flags = *(gfp_t *)flags_ptr;
1528                 names = gfpflag_names;
1529                 break;
1530         default:
1531                 WARN_ONCE(1, "Unsupported flags modifier: %c\n", fmt[1]);
1532                 return buf;
1533         }
1534 
1535         return format_flags(buf, end, flags, names);
1536 }
1537 
1538 static const char *device_node_name_for_depth(const struct device_node *np, int depth)
1539 {
1540         for ( ; np && depth; depth--)
1541                 np = np->parent;
1542 
1543         return kbasename(np->full_name);
1544 }
1545 
1546 static noinline_for_stack
1547 char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end)
1548 {
1549         int depth;
1550         const struct device_node *parent = np->parent;
1551         static const struct printf_spec strspec = {
1552                 .field_width = -1,
1553                 .precision = -1,
1554         };
1555 
1556         /* special case for root node */
1557         if (!parent)
1558                 return string(buf, end, "/", strspec);
1559 
1560         for (depth = 0; parent->parent; depth++)
1561                 parent = parent->parent;
1562 
1563         for ( ; depth >= 0; depth--) {
1564                 buf = string(buf, end, "/", strspec);
1565                 buf = string(buf, end, device_node_name_for_depth(np, depth),
1566                              strspec);
1567         }
1568         return buf;
1569 }
1570 
1571 static noinline_for_stack
1572 char *device_node_string(char *buf, char *end, struct device_node *dn,
1573                          struct printf_spec spec, const char *fmt)
1574 {
1575         char tbuf[sizeof("xxxx") + 1];
1576         const char *p;
1577         int ret;
1578         char *buf_start = buf;
1579         struct property *prop;
1580         bool has_mult, pass;
1581         static const struct printf_spec num_spec = {
1582                 .flags = SMALL,
1583                 .field_width = -1,
1584                 .precision = -1,
1585                 .base = 10,
1586         };
1587 
1588         struct printf_spec str_spec = spec;
1589         str_spec.field_width = -1;
1590 
1591         if (!IS_ENABLED(CONFIG_OF))
1592                 return string(buf, end, "(!OF)", spec);
1593 
1594         if ((unsigned long)dn < PAGE_SIZE)
1595                 return string(buf, end, "(null)", spec);
1596 
1597         /* simple case without anything any more format specifiers */
1598         fmt++;
1599         if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
1600                 fmt = "f";
1601 
1602         for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
1603                 if (pass) {
1604                         if (buf < end)
1605                                 *buf = ':';
1606                         buf++;
1607                 }
1608 
1609                 switch (*fmt) {
1610                 case 'f':       /* full_name */
1611                         buf = device_node_gen_full_name(dn, buf, end);
1612                         break;
1613                 case 'n':       /* name */
1614                         buf = string(buf, end, dn->name, str_spec);
1615                         break;
1616                 case 'p':       /* phandle */
1617                         buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
1618                         break;
1619                 case 'P':       /* path-spec */
1620                         p = kbasename(of_node_full_name(dn));
1621                         if (!p[1])
1622                                 p = "/";
1623                         buf = string(buf, end, p, str_spec);
1624                         break;
1625                 case 'F':       /* flags */
1626                         tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
1627                         tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
1628                         tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
1629                         tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
1630                         tbuf[4] = 0;
1631                         buf = string(buf, end, tbuf, str_spec);
1632                         break;
1633                 case 'c':       /* major compatible string */
1634                         ret = of_property_read_string(dn, "compatible", &p);
1635                         if (!ret)
1636                                 buf = string(buf, end, p, str_spec);
1637                         break;
1638                 case 'C':       /* full compatible string */
1639                         has_mult = false;
1640                         of_property_for_each_string(dn, "compatible", prop, p) {
1641                                 if (has_mult)
1642                                         buf = string(buf, end, ",", str_spec);
1643                                 buf = string(buf, end, "\"", str_spec);
1644                                 buf = string(buf, end, p, str_spec);
1645                                 buf = string(buf, end, "\"", str_spec);
1646 
1647                                 has_mult = true;
1648                         }
1649                         break;
1650                 default:
1651                         break;
1652                 }
1653         }
1654 
1655         return widen_string(buf, buf - buf_start, end, spec);
1656 }
1657 
1658 static noinline_for_stack
1659 char *pointer_string(char *buf, char *end, const void *ptr,
1660                      struct printf_spec spec)
1661 {
1662         spec.base = 16;
1663         spec.flags |= SMALL;
1664         if (spec.field_width == -1) {
1665                 spec.field_width = 2 * sizeof(ptr);
1666                 spec.flags |= ZEROPAD;
1667         }
1668 
1669         return number(buf, end, (unsigned long int)ptr, spec);
1670 }
1671 
1672 static bool have_filled_random_ptr_key __read_mostly;
1673 static siphash_key_t ptr_key __read_mostly;
1674 
1675 static void fill_random_ptr_key(struct random_ready_callback *unused)
1676 {
1677         get_random_bytes(&ptr_key, sizeof(ptr_key));
1678         /*
1679          * have_filled_random_ptr_key==true is dependent on get_random_bytes().
1680          * ptr_to_id() needs to see have_filled_random_ptr_key==true
1681          * after get_random_bytes() returns.
1682          */
1683         smp_mb();
1684         WRITE_ONCE(have_filled_random_ptr_key, true);
1685 }
1686 
1687 static struct random_ready_callback random_ready = {
1688         .func = fill_random_ptr_key
1689 };
1690 
1691 static int __init initialize_ptr_random(void)
1692 {
1693         int ret = add_random_ready_callback(&random_ready);
1694 
1695         if (!ret) {
1696                 return 0;
1697         } else if (ret == -EALREADY) {
1698                 fill_random_ptr_key(&random_ready);
1699                 return 0;
1700         }
1701 
1702         return ret;
1703 }
1704 early_initcall(initialize_ptr_random);
1705 
1706 /* Maps a pointer to a 32 bit unique identifier. */
1707 static char *ptr_to_id(char *buf, char *end, void *ptr, struct printf_spec spec)
1708 {
1709         unsigned long hashval;
1710         const int default_width = 2 * sizeof(ptr);
1711 
1712         if (unlikely(!have_filled_random_ptr_key)) {
1713                 spec.field_width = default_width;
1714                 /* string length must be less than default_width */
1715                 return string(buf, end, "(ptrval)", spec);
1716         }
1717 
1718 #ifdef CONFIG_64BIT
1719         hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
1720         /*
1721          * Mask off the first 32 bits, this makes explicit that we have
1722          * modified the address (and 32 bits is plenty for a unique ID).
1723          */
1724         hashval = hashval & 0xffffffff;
1725 #else
1726         hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
1727 #endif
1728 
1729         spec.flags |= SMALL;
1730         if (spec.field_width == -1) {
1731                 spec.field_width = default_width;
1732                 spec.flags |= ZEROPAD;
1733         }
1734         spec.base = 16;
1735 
1736         return number(buf, end, hashval, spec);
1737 }
1738 
1739 /*
1740  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
1741  * by an extra set of alphanumeric characters that are extended format
1742  * specifiers.
1743  *
1744  * Please update scripts/checkpatch.pl when adding/removing conversion
1745  * characters.  (Search for "check for vsprintf extension").
1746  *
1747  * Right now we handle:
1748  *
1749  * - 'F' For symbolic function descriptor pointers with offset
1750  * - 'f' For simple symbolic function names without offset
1751  * - 'S' For symbolic direct pointers with offset
1752  * - 's' For symbolic direct pointers without offset
1753  * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
1754  * - 'B' For backtraced symbolic direct pointers with offset
1755  * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
1756  * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
1757  * - 'b[l]' For a bitmap, the number of bits is determined by the field
1758  *       width which must be explicitly specified either as part of the
1759  *       format string '%32b[l]' or through '%*b[l]', [l] selects
1760  *       range-list format instead of hex format
1761  * - 'M' For a 6-byte MAC address, it prints the address in the
1762  *       usual colon-separated hex notation
1763  * - 'm' For a 6-byte MAC address, it prints the hex address without colons
1764  * - 'MF' For a 6-byte MAC FDDI address, it prints the address
1765  *       with a dash-separated hex notation
1766  * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
1767  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
1768  *       IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
1769  *       IPv6 uses colon separated network-order 16 bit hex with leading 0's
1770  *       [S][pfs]
1771  *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1772  *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1773  * - 'i' [46] for 'raw' IPv4/IPv6 addresses
1774  *       IPv6 omits the colons (01020304...0f)
1775  *       IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
1776  *       [S][pfs]
1777  *       Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
1778  *       [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
1779  * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
1780  * - 'I[6S]c' for IPv6 addresses printed as specified by
1781  *       http://tools.ietf.org/html/rfc5952
1782  * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
1783  *                of the following flags (see string_escape_mem() for the
1784  *                details):
1785  *                  a - ESCAPE_ANY
1786  *                  c - ESCAPE_SPECIAL
1787  *                  h - ESCAPE_HEX
1788  *                  n - ESCAPE_NULL
1789  *                  o - ESCAPE_OCTAL
1790  *                  p - ESCAPE_NP
1791  *                  s - ESCAPE_SPACE
1792  *                By default ESCAPE_ANY_NP is used.
1793  * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
1794  *       "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
1795  *       Options for %pU are:
1796  *         b big endian lower case hex (default)
1797  *         B big endian UPPER case hex
1798  *         l little endian lower case hex
1799  *         L little endian UPPER case hex
1800  *           big endian output byte order is:
1801  *             [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
1802  *           little endian output byte order is:
1803  *             [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
1804  * - 'V' For a struct va_format which contains a format string * and va_list *,
1805  *       call vsnprintf(->format, *->va_list).
1806  *       Implements a "recursive vsnprintf".
1807  *       Do not use this feature without some mechanism to verify the
1808  *       correctness of the format string and va_list arguments.
1809  * - 'K' For a kernel pointer that should be hidden from unprivileged users
1810  * - 'NF' For a netdev_features_t
1811  * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
1812  *            a certain separator (' ' by default):
1813  *              C colon
1814  *              D dash
1815  *              N no separator
1816  *            The maximum supported length is 64 bytes of the input. Consider
1817  *            to use print_hex_dump() for the larger input.
1818  * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
1819  *           (default assumed to be phys_addr_t, passed by reference)
1820  * - 'd[234]' For a dentry name (optionally 2-4 last components)
1821  * - 'D[234]' Same as 'd' but for a struct file
1822  * - 'g' For block_device name (gendisk + partition number)
1823  * - 'C' For a clock, it prints the name (Common Clock Framework) or address
1824  *       (legacy clock framework) of the clock
1825  * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
1826  *        (legacy clock framework) of the clock
1827  * - 'Cr' For a clock, it prints the current rate of the clock
1828  * - 'G' For flags to be printed as a collection of symbolic strings that would
1829  *       construct the specific value. Supported flags given by option:
1830  *       p page flags (see struct page) given as pointer to unsigned long
1831  *       g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
1832  *       v vma flags (VM_*) given as pointer to unsigned long
1833  * - 'O' For a kobject based struct. Must be one of the following:
1834  *       - 'OF[fnpPcCF]'  For a device tree object
1835  *                        Without any optional arguments prints the full_name
1836  *                        f device node full_name
1837  *                        n device node name
1838  *                        p device node phandle
1839  *                        P device node path spec (name + @unit)
1840  *                        F device node flags
1841  *                        c major compatible string
1842  *                        C full compatible string
1843  *
1844  * - 'x' For printing the address. Equivalent to "%lx".
1845  *
1846  * ** When making changes please also update:
1847  *      Documentation/core-api/printk-formats.rst
1848  *
1849  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
1850  * function pointers are really function descriptors, which contain a
1851  * pointer to the real address.
1852  *
1853  * Note: The default behaviour (unadorned %p) is to hash the address,
1854  * rendering it useful as a unique identifier.
1855  */
1856 static noinline_for_stack
1857 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
1858               struct printf_spec spec)
1859 {
1860         const int default_width = 2 * sizeof(void *);
1861 
1862         if (!ptr && *fmt != 'K' && *fmt != 'x') {
1863                 /*
1864                  * Print (null) with the same width as a pointer so it makes
1865                  * tabular output look nice.
1866                  */
1867                 if (spec.field_width == -1)
1868                         spec.field_width = default_width;
1869                 return string(buf, end, "(null)", spec);
1870         }
1871 
1872         switch (*fmt) {
1873         case 'F':
1874         case 'f':
1875         case 'S':
1876         case 's':
1877                 ptr = dereference_symbol_descriptor(ptr);
1878                 /* Fallthrough */
1879         case 'B':
1880                 return symbol_string(buf, end, ptr, spec, fmt);
1881         case 'R':
1882         case 'r':
1883                 return resource_string(buf, end, ptr, spec, fmt);
1884         case 'h':
1885                 return hex_string(buf, end, ptr, spec, fmt);
1886         case 'b':
1887                 switch (fmt[1]) {
1888                 case 'l':
1889                         return bitmap_list_string(buf, end, ptr, spec, fmt);
1890                 default:
1891                         return bitmap_string(buf, end, ptr, spec, fmt);
1892                 }
1893         case 'M':                       /* Colon separated: 00:01:02:03:04:05 */
1894         case 'm':                       /* Contiguous: 000102030405 */
1895                                         /* [mM]F (FDDI) */
1896                                         /* [mM]R (Reverse order; Bluetooth) */
1897                 return mac_address_string(buf, end, ptr, spec, fmt);
1898         case 'I':                       /* Formatted IP supported
1899                                          * 4:   1.2.3.4
1900                                          * 6:   0001:0203:...:0708
1901                                          * 6c:  1::708 or 1::1.2.3.4
1902                                          */
1903         case 'i':                       /* Contiguous:
1904                                          * 4:   001.002.003.004
1905                                          * 6:   000102...0f
1906                                          */
1907                 switch (fmt[1]) {
1908                 case '6':
1909                         return ip6_addr_string(buf, end, ptr, spec, fmt);
1910                 case '4':
1911                         return ip4_addr_string(buf, end, ptr, spec, fmt);
1912                 case 'S': {
1913                         const union {
1914                                 struct sockaddr         raw;
1915                                 struct sockaddr_in      v4;
1916                                 struct sockaddr_in6     v6;
1917                         } *sa = ptr;
1918 
1919                         switch (sa->raw.sa_family) {
1920                         case AF_INET:
1921                                 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1922                         case AF_INET6:
1923                                 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1924                         default:
1925                                 return string(buf, end, "(invalid address)", spec);
1926                         }}
1927                 }
1928                 break;
1929         case 'E':
1930                 return escaped_string(buf, end, ptr, spec, fmt);
1931         case 'U':
1932                 return uuid_string(buf, end, ptr, spec, fmt);
1933         case 'V':
1934                 {
1935                         va_list va;
1936 
1937                         va_copy(va, *((struct va_format *)ptr)->va);
1938                         buf += vsnprintf(buf, end > buf ? end - buf : 0,
1939                                          ((struct va_format *)ptr)->fmt, va);
1940                         va_end(va);
1941                         return buf;
1942                 }
1943         case 'K':
1944                 if (!kptr_restrict)
1945                         break;
1946                 return restricted_pointer(buf, end, ptr, spec);
1947         case 'N':
1948                 return netdev_bits(buf, end, ptr, fmt);
1949         case 'a':
1950                 return address_val(buf, end, ptr, fmt);
1951         case 'd':
1952                 return dentry_name(buf, end, ptr, spec, fmt);
1953         case 'C':
1954                 return clock(buf, end, ptr, spec, fmt);
1955         case 'D':
1956                 return dentry_name(buf, end,
1957                                    ((const struct file *)ptr)->f_path.dentry,
1958                                    spec, fmt);
1959 #ifdef CONFIG_BLOCK
1960         case 'g':
1961                 return bdev_name(buf, end, ptr, spec, fmt);
1962 #endif
1963 
1964         case 'G':
1965                 return flags_string(buf, end, ptr, fmt);
1966         case 'O':
1967                 switch (fmt[1]) {
1968                 case 'F':
1969                         return device_node_string(buf, end, ptr, spec, fmt + 1);
1970                 }
1971         case 'x':
1972                 return pointer_string(buf, end, ptr, spec);
1973         }
1974 
1975         /* default is to _not_ leak addresses, hash before printing */
1976         return ptr_to_id(buf, end, ptr, spec);
1977 }
1978 
1979 /*
1980  * Helper function to decode printf style format.
1981  * Each call decode a token from the format and return the
1982  * number of characters read (or likely the delta where it wants
1983  * to go on the next call).
1984  * The decoded token is returned through the parameters
1985  *
1986  * 'h', 'l', or 'L' for integer fields
1987  * 'z' support added 23/7/1999 S.H.
1988  * 'z' changed to 'Z' --davidm 1/25/99
1989  * 'Z' changed to 'z' --adobriyan 2017-01-25
1990  * 't' added for ptrdiff_t
1991  *
1992  * @fmt: the format string
1993  * @type of the token returned
1994  * @flags: various flags such as +, -, # tokens..
1995  * @field_width: overwritten width
1996  * @base: base of the number (octal, hex, ...)
1997  * @precision: precision of a number
1998  * @qualifier: qualifier of a number (long, size_t, ...)
1999  */
2000 static noinline_for_stack
2001 int format_decode(const char *fmt, struct printf_spec *spec)
2002 {
2003         const char *start = fmt;
2004         char qualifier;
2005 
2006         /* we finished early by reading the field width */
2007         if (spec->type == FORMAT_TYPE_WIDTH) {
2008                 if (spec->field_width < 0) {
2009                         spec->field_width = -spec->field_width;
2010                         spec->flags |= LEFT;
2011                 }
2012                 spec->type = FORMAT_TYPE_NONE;
2013                 goto precision;
2014         }
2015 
2016         /* we finished early by reading the precision */
2017         if (spec->type == FORMAT_TYPE_PRECISION) {
2018                 if (spec->precision < 0)
2019                         spec->precision = 0;
2020 
2021                 spec->type = FORMAT_TYPE_NONE;
2022                 goto qualifier;
2023         }
2024 
2025         /* By default */
2026         spec->type = FORMAT_TYPE_NONE;
2027 
2028         for (; *fmt ; ++fmt) {
2029                 if (*fmt == '%')
2030                         break;
2031         }
2032 
2033         /* Return the current non-format string */
2034         if (fmt != start || !*fmt)
2035                 return fmt - start;
2036 
2037         /* Process flags */
2038         spec->flags = 0;
2039 
2040         while (1) { /* this also skips first '%' */
2041                 bool found = true;
2042 
2043                 ++fmt;
2044 
2045                 switch (*fmt) {
2046                 case '-': spec->flags |= LEFT;    break;
2047                 case '+': spec->flags |= PLUS;    break;
2048                 case ' ': spec->flags |= SPACE;   break;
2049                 case '#': spec->flags |= SPECIAL; break;
2050                 case '': spec->flags |= ZEROPAD; break;
2051                 default:  found = false;
2052                 }
2053 
2054                 if (!found)
2055                         break;
2056         }
2057 
2058         /* get field width */
2059         spec->field_width = -1;
2060 
2061         if (isdigit(*fmt))
2062                 spec->field_width = skip_atoi(&fmt);
2063         else if (*fmt == '*') {
2064                 /* it's the next argument */
2065                 spec->type = FORMAT_TYPE_WIDTH;
2066                 return ++fmt - start;
2067         }
2068 
2069 precision:
2070         /* get the precision */
2071         spec->precision = -1;
2072         if (*fmt == '.') {
2073                 ++fmt;
2074                 if (isdigit(*fmt)) {
2075                         spec->precision = skip_atoi(&fmt);
2076                         if (spec->precision < 0)
2077                                 spec->precision = 0;
2078                 } else if (*fmt == '*') {
2079                         /* it's the next argument */
2080                         spec->type = FORMAT_TYPE_PRECISION;
2081                         return ++fmt - start;
2082                 }
2083         }
2084 
2085 qualifier:
2086         /* get the conversion qualifier */
2087         qualifier = 0;
2088         if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2089             *fmt == 'z' || *fmt == 't') {
2090                 qualifier = *fmt++;
2091                 if (unlikely(qualifier == *fmt)) {
2092                         if (qualifier == 'l') {
2093                                 qualifier = 'L';
2094                                 ++fmt;
2095                         } else if (qualifier == 'h') {
2096                                 qualifier = 'H';
2097                                 ++fmt;
2098                         }
2099                 }
2100         }
2101 
2102         /* default base */
2103         spec->base = 10;
2104         switch (*fmt) {
2105         case 'c':
2106                 spec->type = FORMAT_TYPE_CHAR;
2107                 return ++fmt - start;
2108 
2109         case 's':
2110                 spec->type = FORMAT_TYPE_STR;
2111                 return ++fmt - start;
2112 
2113         case 'p':
2114                 spec->type = FORMAT_TYPE_PTR;
2115                 return ++fmt - start;
2116 
2117         case '%':
2118                 spec->type = FORMAT_TYPE_PERCENT_CHAR;
2119                 return ++fmt - start;
2120 
2121         /* integer number formats - set up the flags and "break" */
2122         case 'o':
2123                 spec->base = 8;
2124                 break;
2125 
2126         case 'x':
2127                 spec->flags |= SMALL;
2128 
2129         case 'X':
2130                 spec->base = 16;
2131                 break;
2132 
2133         case 'd':
2134         case 'i':
2135                 spec->flags |= SIGN;
2136         case 'u':
2137                 break;
2138 
2139         case 'n':
2140                 /*
2141                  * Since %n poses a greater security risk than
2142                  * utility, treat it as any other invalid or
2143                  * unsupported format specifier.
2144                  */
2145                 /* Fall-through */
2146 
2147         default:
2148                 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2149                 spec->type = FORMAT_TYPE_INVALID;
2150                 return fmt - start;
2151         }
2152 
2153         if (qualifier == 'L')
2154                 spec->type = FORMAT_TYPE_LONG_LONG;
2155         else if (qualifier == 'l') {
2156                 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2157                 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2158         } else if (qualifier == 'z') {
2159                 spec->type = FORMAT_TYPE_SIZE_T;
2160         } else if (qualifier == 't') {
2161                 spec->type = FORMAT_TYPE_PTRDIFF;
2162         } else if (qualifier == 'H') {
2163                 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2164                 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2165         } else if (qualifier == 'h') {
2166                 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2167                 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2168         } else {
2169                 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2170                 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2171         }
2172 
2173         return ++fmt - start;
2174 }
2175 
2176 static void
2177 set_field_width(struct printf_spec *spec, int width)
2178 {
2179         spec->field_width = width;
2180         if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2181                 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2182         }
2183 }
2184 
2185 static void
2186 set_precision(struct printf_spec *spec, int prec)
2187 {
2188         spec->precision = prec;
2189         if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2190                 spec->precision = clamp(prec, 0, PRECISION_MAX);
2191         }
2192 }
2193 
2194 /**
2195  * vsnprintf - Format a string and place it in a buffer
2196  * @buf: The buffer to place the result into
2197  * @size: The size of the buffer, including the trailing null space
2198  * @fmt: The format string to use
2199  * @args: Arguments for the format string
2200  *
2201  * This function generally follows C99 vsnprintf, but has some
2202  * extensions and a few limitations:
2203  *
2204  *  - ``%n`` is unsupported
2205  *  - ``%p*`` is handled by pointer()
2206  *
2207  * See pointer() or Documentation/core-api/printk-formats.rst for more
2208  * extensive description.
2209  *
2210  * **Please update the documentation in both places when making changes**
2211  *
2212  * The return value is the number of characters which would
2213  * be generated for the given input, excluding the trailing
2214  * '\0', as per ISO C99. If you want to have the exact
2215  * number of characters written into @buf as return value
2216  * (not including the trailing '\0'), use vscnprintf(). If the
2217  * return is greater than or equal to @size, the resulting
2218  * string is truncated.
2219  *
2220  * If you're not already dealing with a va_list consider using snprintf().
2221  */
2222 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2223 {
2224         unsigned long long num;
2225         char *str, *end;
2226         struct printf_spec spec = {0};
2227 
2228         /* Reject out-of-range values early.  Large positive sizes are
2229            used for unknown buffer sizes. */
2230         if (WARN_ON_ONCE(size > INT_MAX))
2231                 return 0;
2232 
2233         str = buf;
2234         end = buf + size;
2235 
2236         /* Make sure end is always >= buf */
2237         if (end < buf) {
2238                 end = ((void *)-1);
2239                 size = end - buf;
2240         }
2241 
2242         while (*fmt) {
2243                 const char *old_fmt = fmt;
2244                 int read = format_decode(fmt, &spec);
2245 
2246                 fmt += read;
2247 
2248                 switch (spec.type) {
2249                 case FORMAT_TYPE_NONE: {
2250                         int copy = read;
2251                         if (str < end) {
2252                                 if (copy > end - str)
2253                                         copy = end - str;
2254                                 memcpy(str, old_fmt, copy);
2255                         }
2256                         str += read;
2257                         break;
2258                 }
2259 
2260                 case FORMAT_TYPE_WIDTH:
2261                         set_field_width(&spec, va_arg(args, int));
2262                         break;
2263 
2264                 case FORMAT_TYPE_PRECISION:
2265                         set_precision(&spec, va_arg(args, int));
2266                         break;
2267 
2268                 case FORMAT_TYPE_CHAR: {
2269                         char c;
2270 
2271                         if (!(spec.flags & LEFT)) {
2272                                 while (--spec.field_width > 0) {
2273                                         if (str < end)
2274                                                 *str = ' ';
2275                                         ++str;
2276 
2277                                 }
2278                         }
2279                         c = (unsigned char) va_arg(args, int);
2280                         if (str < end)
2281                                 *str = c;
2282                         ++str;
2283                         while (--spec.field_width > 0) {
2284                                 if (str < end)
2285                                         *str = ' ';
2286                                 ++str;
2287                         }
2288                         break;
2289                 }
2290 
2291                 case FORMAT_TYPE_STR:
2292                         str = string(str, end, va_arg(args, char *), spec);
2293                         break;
2294 
2295                 case FORMAT_TYPE_PTR:
2296                         str = pointer(fmt, str, end, va_arg(args, void *),
2297                                       spec);
2298                         while (isalnum(*fmt))
2299                                 fmt++;
2300                         break;
2301 
2302                 case FORMAT_TYPE_PERCENT_CHAR:
2303                         if (str < end)
2304                                 *str = '%';
2305                         ++str;
2306                         break;
2307 
2308                 case FORMAT_TYPE_INVALID:
2309                         /*
2310                          * Presumably the arguments passed gcc's type
2311                          * checking, but there is no safe or sane way
2312                          * for us to continue parsing the format and
2313                          * fetching from the va_list; the remaining
2314                          * specifiers and arguments would be out of
2315                          * sync.
2316                          */
2317                         goto out;
2318 
2319                 default:
2320                         switch (spec.type) {
2321                         case FORMAT_TYPE_LONG_LONG:
2322                                 num = va_arg(args, long long);
2323                                 break;
2324                         case FORMAT_TYPE_ULONG:
2325                                 num = va_arg(args, unsigned long);
2326                                 break;
2327                         case FORMAT_TYPE_LONG:
2328                                 num = va_arg(args, long);
2329                                 break;
2330                         case FORMAT_TYPE_SIZE_T:
2331                                 if (spec.flags & SIGN)
2332                                         num = va_arg(args, ssize_t);
2333                                 else
2334                                         num = va_arg(args, size_t);
2335                                 break;
2336                         case FORMAT_TYPE_PTRDIFF:
2337                                 num = va_arg(args, ptrdiff_t);
2338                                 break;
2339                         case FORMAT_TYPE_UBYTE:
2340                                 num = (unsigned char) va_arg(args, int);
2341                                 break;
2342                         case FORMAT_TYPE_BYTE:
2343                                 num = (signed char) va_arg(args, int);
2344                                 break;
2345                         case FORMAT_TYPE_USHORT:
2346                                 num = (unsigned short) va_arg(args, int);
2347                                 break;
2348                         case FORMAT_TYPE_SHORT:
2349                                 num = (short) va_arg(args, int);
2350                                 break;
2351                         case FORMAT_TYPE_INT:
2352                                 num = (int) va_arg(args, int);
2353                                 break;
2354                         default:
2355                                 num = va_arg(args, unsigned int);
2356                         }
2357 
2358                         str = number(str, end, num, spec);
2359                 }
2360         }
2361 
2362 out:
2363         if (size > 0) {
2364                 if (str < end)
2365                         *str = '\0';
2366                 else
2367                         end[-1] = '\0';
2368         }
2369 
2370         /* the trailing null byte doesn't count towards the total */
2371         return str-buf;
2372 
2373 }
2374 EXPORT_SYMBOL(vsnprintf);
2375 
2376 /**
2377  * vscnprintf - Format a string and place it in a buffer
2378  * @buf: The buffer to place the result into
2379  * @size: The size of the buffer, including the trailing null space
2380  * @fmt: The format string to use
2381  * @args: Arguments for the format string
2382  *
2383  * The return value is the number of characters which have been written into
2384  * the @buf not including the trailing '\0'. If @size is == 0 the function
2385  * returns 0.
2386  *
2387  * If you're not already dealing with a va_list consider using scnprintf().
2388  *
2389  * See the vsnprintf() documentation for format string extensions over C99.
2390  */
2391 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2392 {
2393         int i;
2394 
2395         i = vsnprintf(buf, size, fmt, args);
2396 
2397         if (likely(i < size))
2398                 return i;
2399         if (size != 0)
2400                 return size - 1;
2401         return 0;
2402 }
2403 EXPORT_SYMBOL(vscnprintf);
2404 
2405 /**
2406  * snprintf - Format a string and place it in a buffer
2407  * @buf: The buffer to place the result into
2408  * @size: The size of the buffer, including the trailing null space
2409  * @fmt: The format string to use
2410  * @...: Arguments for the format string
2411  *
2412  * The return value is the number of characters which would be
2413  * generated for the given input, excluding the trailing null,
2414  * as per ISO C99.  If the return is greater than or equal to
2415  * @size, the resulting string is truncated.
2416  *
2417  * See the vsnprintf() documentation for format string extensions over C99.
2418  */
2419 int snprintf(char *buf, size_t size, const char *fmt, ...)
2420 {
2421         va_list args;
2422         int i;
2423 
2424         va_start(args, fmt);
2425         i = vsnprintf(buf, size, fmt, args);
2426         va_end(args);
2427 
2428         return i;
2429 }
2430 EXPORT_SYMBOL(snprintf);
2431 
2432 /**
2433  * scnprintf - Format a string and place it in a buffer
2434  * @buf: The buffer to place the result into
2435  * @size: The size of the buffer, including the trailing null space
2436  * @fmt: The format string to use
2437  * @...: Arguments for the format string
2438  *
2439  * The return value is the number of characters written into @buf not including
2440  * the trailing '\0'. If @size is == 0 the function returns 0.
2441  */
2442 
2443 int scnprintf(char *buf, size_t size, const char *fmt, ...)
2444 {
2445         va_list args;
2446         int i;
2447 
2448         va_start(args, fmt);
2449         i = vscnprintf(buf, size, fmt, args);
2450         va_end(args);
2451 
2452         return i;
2453 }
2454 EXPORT_SYMBOL(scnprintf);
2455 
2456 /**
2457  * vsprintf - Format a string and place it in a buffer
2458  * @buf: The buffer to place the result into
2459  * @fmt: The format string to use
2460  * @args: Arguments for the format string
2461  *
2462  * The function returns the number of characters written
2463  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2464  * buffer overflows.
2465  *
2466  * If you're not already dealing with a va_list consider using sprintf().
2467  *
2468  * See the vsnprintf() documentation for format string extensions over C99.
2469  */
2470 int vsprintf(char *buf, const char *fmt, va_list args)
2471 {
2472         return vsnprintf(buf, INT_MAX, fmt, args);
2473 }
2474 EXPORT_SYMBOL(vsprintf);
2475 
2476 /**
2477  * sprintf - Format a string and place it in a buffer
2478  * @buf: The buffer to place the result into
2479  * @fmt: The format string to use
2480  * @...: Arguments for the format string
2481  *
2482  * The function returns the number of characters written
2483  * into @buf. Use snprintf() or scnprintf() in order to avoid
2484  * buffer overflows.
2485  *
2486  * See the vsnprintf() documentation for format string extensions over C99.
2487  */
2488 int sprintf(char *buf, const char *fmt, ...)
2489 {
2490         va_list args;
2491         int i;
2492 
2493         va_start(args, fmt);
2494         i = vsnprintf(buf, INT_MAX, fmt, args);
2495         va_end(args);
2496 
2497         return i;
2498 }
2499 EXPORT_SYMBOL(sprintf);
2500 
2501 #ifdef CONFIG_BINARY_PRINTF
2502 /*
2503  * bprintf service:
2504  * vbin_printf() - VA arguments to binary data
2505  * bstr_printf() - Binary data to text string
2506  */
2507 
2508 /**
2509  * vbin_printf - Parse a format string and place args' binary value in a buffer
2510  * @bin_buf: The buffer to place args' binary value
2511  * @size: The size of the buffer(by words(32bits), not characters)
2512  * @fmt: The format string to use
2513  * @args: Arguments for the format string
2514  *
2515  * The format follows C99 vsnprintf, except %n is ignored, and its argument
2516  * is skipped.
2517  *
2518  * The return value is the number of words(32bits) which would be generated for
2519  * the given input.
2520  *
2521  * NOTE:
2522  * If the return value is greater than @size, the resulting bin_buf is NOT
2523  * valid for bstr_printf().
2524  */
2525 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2526 {
2527         struct printf_spec spec = {0};
2528         char *str, *end;
2529         int width;
2530 
2531         str = (char *)bin_buf;
2532         end = (char *)(bin_buf + size);
2533 
2534 #define save_arg(type)                                                  \
2535 ({                                                                      \
2536         unsigned long long value;                                       \
2537         if (sizeof(type) == 8) {                                        \
2538                 unsigned long long val8;                                \
2539                 str = PTR_ALIGN(str, sizeof(u32));                      \
2540                 val8 = va_arg(args, unsigned long long);                \
2541                 if (str + sizeof(type) <= end) {                        \
2542                         *(u32 *)str = *(u32 *)&val8;                    \
2543                         *(u32 *)(str + 4) = *((u32 *)&val8 + 1);        \
2544                 }                                                       \
2545                 value = val8;                                           \
2546         } else {                                                        \
2547                 unsigned int val4;                                      \
2548                 str = PTR_ALIGN(str, sizeof(type));                     \
2549                 val4 = va_arg(args, int);                               \
2550                 if (str + sizeof(type) <= end)                          \
2551                         *(typeof(type) *)str = (type)(long)val4;        \
2552                 value = (unsigned long long)val4;                       \
2553         }                                                               \
2554         str += sizeof(type);                                            \
2555         value;                                                          \
2556 })
2557 
2558         while (*fmt) {
2559                 int read = format_decode(fmt, &spec);
2560 
2561                 fmt += read;
2562 
2563                 switch (spec.type) {
2564                 case FORMAT_TYPE_NONE:
2565                 case FORMAT_TYPE_PERCENT_CHAR:
2566                         break;
2567                 case FORMAT_TYPE_INVALID:
2568                         goto out;
2569 
2570                 case FORMAT_TYPE_WIDTH:
2571                 case FORMAT_TYPE_PRECISION:
2572                         width = (int)save_arg(int);
2573                         /* Pointers may require the width */
2574                         if (*fmt == 'p')
2575                                 set_field_width(&spec, width);
2576                         break;
2577 
2578                 case FORMAT_TYPE_CHAR:
2579                         save_arg(char);
2580                         break;
2581 
2582                 case FORMAT_TYPE_STR: {
2583                         const char *save_str = va_arg(args, char *);
2584                         size_t len;
2585 
2586                         if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
2587                                         || (unsigned long)save_str < PAGE_SIZE)
2588                                 save_str = "(null)";
2589                         len = strlen(save_str) + 1;
2590                         if (str + len < end)
2591                                 memcpy(str, save_str, len);
2592                         str += len;
2593                         break;
2594                 }
2595 
2596                 case FORMAT_TYPE_PTR:
2597                         /* Dereferenced pointers must be done now */
2598                         switch (*fmt) {
2599                         /* Dereference of functions is still OK */
2600                         case 'S':
2601                         case 's':
2602                         case 'F':
2603                         case 'f':
2604                         case 'x':
2605                         case 'K':
2606                                 save_arg(void *);
2607                                 break;
2608                         default:
2609                                 if (!isalnum(*fmt)) {
2610                                         save_arg(void *);
2611                                         break;
2612                                 }
2613                                 str = pointer(fmt, str, end, va_arg(args, void *),
2614                                               spec);
2615                                 if (str + 1 < end)
2616                                         *str++ = '\0';
2617                                 else
2618                                         end[-1] = '\0'; /* Must be nul terminated */
2619                         }
2620                         /* skip all alphanumeric pointer suffixes */
2621                         while (isalnum(*fmt))
2622                                 fmt++;
2623                         break;
2624 
2625                 default:
2626                         switch (spec.type) {
2627 
2628                         case FORMAT_TYPE_LONG_LONG:
2629                                 save_arg(long long);
2630                                 break;
2631                         case FORMAT_TYPE_ULONG:
2632                         case FORMAT_TYPE_LONG:
2633                                 save_arg(unsigned long);
2634                                 break;
2635                         case FORMAT_TYPE_SIZE_T:
2636                                 save_arg(size_t);
2637                                 break;
2638                         case FORMAT_TYPE_PTRDIFF:
2639                                 save_arg(ptrdiff_t);
2640                                 break;
2641                         case FORMAT_TYPE_UBYTE:
2642                         case FORMAT_TYPE_BYTE:
2643                                 save_arg(char);
2644                                 break;
2645                         case FORMAT_TYPE_USHORT:
2646                         case FORMAT_TYPE_SHORT:
2647                                 save_arg(short);
2648                                 break;
2649                         default:
2650                                 save_arg(int);
2651                         }
2652                 }
2653         }
2654 
2655 out:
2656         return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2657 #undef save_arg
2658 }
2659 EXPORT_SYMBOL_GPL(vbin_printf);
2660 
2661 /**
2662  * bstr_printf - Format a string from binary arguments and place it in a buffer
2663  * @buf: The buffer to place the result into
2664  * @size: The size of the buffer, including the trailing null space
2665  * @fmt: The format string to use
2666  * @bin_buf: Binary arguments for the format string
2667  *
2668  * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2669  * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2670  * a binary buffer that generated by vbin_printf.
2671  *
2672  * The format follows C99 vsnprintf, but has some extensions:
2673  *  see vsnprintf comment for details.
2674  *
2675  * The return value is the number of characters which would
2676  * be generated for the given input, excluding the trailing
2677  * '\0', as per ISO C99. If you want to have the exact
2678  * number of characters written into @buf as return value
2679  * (not including the trailing '\0'), use vscnprintf(). If the
2680  * return is greater than or equal to @size, the resulting
2681  * string is truncated.
2682  */
2683 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2684 {
2685         struct printf_spec spec = {0};
2686         char *str, *end;
2687         const char *args = (const char *)bin_buf;
2688 
2689         if (WARN_ON_ONCE(size > INT_MAX))
2690                 return 0;
2691 
2692         str = buf;
2693         end = buf + size;
2694 
2695 #define get_arg(type)                                                   \
2696 ({                                                                      \
2697         typeof(type) value;                                             \
2698         if (sizeof(type) == 8) {                                        \
2699                 args = PTR_ALIGN(args, sizeof(u32));                    \
2700                 *(u32 *)&value = *(u32 *)args;                          \
2701                 *((u32 *)&value + 1) = *(u32 *)(args + 4);              \
2702         } else {                                                        \
2703                 args = PTR_ALIGN(args, sizeof(type));                   \
2704                 value = *(typeof(type) *)args;                          \
2705         }                                                               \
2706         args += sizeof(type);                                           \
2707         value;                                                          \
2708 })
2709 
2710         /* Make sure end is always >= buf */
2711         if (end < buf) {
2712                 end = ((void *)-1);
2713                 size = end - buf;
2714         }
2715 
2716         while (*fmt) {
2717                 const char *old_fmt = fmt;
2718                 int read = format_decode(fmt, &spec);
2719 
2720                 fmt += read;
2721 
2722                 switch (spec.type) {
2723                 case FORMAT_TYPE_NONE: {
2724                         int copy = read;
2725                         if (str < end) {
2726                                 if (copy > end - str)
2727                                         copy = end - str;
2728                                 memcpy(str, old_fmt, copy);
2729                         }
2730                         str += read;
2731                         break;
2732                 }
2733 
2734                 case FORMAT_TYPE_WIDTH:
2735                         set_field_width(&spec, get_arg(int));
2736                         break;
2737 
2738                 case FORMAT_TYPE_PRECISION:
2739                         set_precision(&spec, get_arg(int));
2740                         break;
2741 
2742                 case FORMAT_TYPE_CHAR: {
2743                         char c;
2744 
2745                         if (!(spec.flags & LEFT)) {
2746                                 while (--spec.field_width > 0) {
2747                                         if (str < end)
2748                                                 *str = ' ';
2749                                         ++str;
2750                                 }
2751                         }
2752                         c = (unsigned char) get_arg(char);
2753                         if (str < end)
2754                                 *str = c;
2755                         ++str;
2756                         while (--spec.field_width > 0) {
2757                                 if (str < end)
2758                                         *str = ' ';
2759                                 ++str;
2760                         }
2761                         break;
2762                 }
2763 
2764                 case FORMAT_TYPE_STR: {
2765                         const char *str_arg = args;
2766                         args += strlen(str_arg) + 1;
2767                         str = string(str, end, (char *)str_arg, spec);
2768                         break;
2769                 }
2770 
2771                 case FORMAT_TYPE_PTR: {
2772                         bool process = false;
2773                         int copy, len;
2774                         /* Non function dereferences were already done */
2775                         switch (*fmt) {
2776                         case 'S':
2777                         case 's':
2778                         case 'F':
2779                         case 'f':
2780                         case 'x':
2781                         case 'K':
2782                                 process = true;
2783                                 break;
2784                         default:
2785                                 if (!isalnum(*fmt)) {
2786                                         process = true;
2787                                         break;
2788                                 }
2789                                 /* Pointer dereference was already processed */
2790                                 if (str < end) {
2791                                         len = copy = strlen(args);
2792                                         if (copy > end - str)
2793                                                 copy = end - str;
2794                                         memcpy(str, args, copy);
2795                                         str += len;
2796                                         args += len;
2797                                 }
2798                         }
2799                         if (process)
2800                                 str = pointer(fmt, str, end, get_arg(void *), spec);
2801 
2802                         while (isalnum(*fmt))
2803                                 fmt++;
2804                         break;
2805                 }
2806 
2807                 case FORMAT_TYPE_PERCENT_CHAR:
2808                         if (str < end)
2809                                 *str = '%';
2810                         ++str;
2811                         break;
2812 
2813                 case FORMAT_TYPE_INVALID:
2814                         goto out;
2815 
2816                 default: {
2817                         unsigned long long num;
2818 
2819                         switch (spec.type) {
2820 
2821                         case FORMAT_TYPE_LONG_LONG:
2822                                 num = get_arg(long long);
2823                                 break;
2824                         case FORMAT_TYPE_ULONG:
2825                         case FORMAT_TYPE_LONG:
2826                                 num = get_arg(unsigned long);
2827                                 break;
2828                         case FORMAT_TYPE_SIZE_T:
2829                                 num = get_arg(size_t);
2830                                 break;
2831                         case FORMAT_TYPE_PTRDIFF:
2832                                 num = get_arg(ptrdiff_t);
2833                                 break;
2834                         case FORMAT_TYPE_UBYTE:
2835                                 num = get_arg(unsigned char);
2836                                 break;
2837                         case FORMAT_TYPE_BYTE:
2838                                 num = get_arg(signed char);
2839                                 break;
2840                         case FORMAT_TYPE_USHORT:
2841                                 num = get_arg(unsigned short);
2842                                 break;
2843                         case FORMAT_TYPE_SHORT:
2844                                 num = get_arg(short);
2845                                 break;
2846                         case FORMAT_TYPE_UINT:
2847                                 num = get_arg(unsigned int);
2848                                 break;
2849                         default:
2850                                 num = get_arg(int);
2851                         }
2852 
2853                         str = number(str, end, num, spec);
2854                 } /* default: */
2855                 } /* switch(spec.type) */
2856         } /* while(*fmt) */
2857 
2858 out:
2859         if (size > 0) {
2860                 if (str < end)
2861                         *str = '\0';
2862                 else
2863                         end[-1] = '\0';
2864         }
2865 
2866 #undef get_arg
2867 
2868         /* the trailing null byte doesn't count towards the total */
2869         return str - buf;
2870 }
2871 EXPORT_SYMBOL_GPL(bstr_printf);
2872 
2873 /**
2874  * bprintf - Parse a format string and place args' binary value in a buffer
2875  * @bin_buf: The buffer to place args' binary value
2876  * @size: The size of the buffer(by words(32bits), not characters)
2877  * @fmt: The format string to use
2878  * @...: Arguments for the format string
2879  *
2880  * The function returns the number of words(u32) written
2881  * into @bin_buf.
2882  */
2883 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
2884 {
2885         va_list args;
2886         int ret;
2887 
2888         va_start(args, fmt);
2889         ret = vbin_printf(bin_buf, size, fmt, args);
2890         va_end(args);
2891 
2892         return ret;
2893 }
2894 EXPORT_SYMBOL_GPL(bprintf);
2895 
2896 #endif /* CONFIG_BINARY_PRINTF */
2897 
2898 /**
2899  * vsscanf - Unformat a buffer into a list of arguments
2900  * @buf:        input buffer
2901  * @fmt:        format of buffer
2902  * @args:       arguments
2903  */
2904 int vsscanf(const char *buf, const char *fmt, va_list args)
2905 {
2906         const char *str = buf;
2907         char *next;
2908         char digit;
2909         int num = 0;
2910         u8 qualifier;
2911         unsigned int base;
2912         union {
2913                 long long s;
2914                 unsigned long long u;
2915         } val;
2916         s16 field_width;
2917         bool is_sign;
2918 
2919         while (*fmt) {
2920                 /* skip any white space in format */
2921                 /* white space in format matchs any amount of
2922                  * white space, including none, in the input.
2923                  */
2924                 if (isspace(*fmt)) {
2925                         fmt = skip_spaces(++fmt);
2926                         str = skip_spaces(str);
2927                 }
2928 
2929                 /* anything that is not a conversion must match exactly */
2930                 if (*fmt != '%' && *fmt) {
2931                         if (*fmt++ != *str++)
2932                                 break;
2933                         continue;
2934                 }
2935 
2936                 if (!*fmt)
2937                         break;
2938                 ++fmt;
2939 
2940                 /* skip this conversion.
2941                  * advance both strings to next white space
2942                  */
2943                 if (*fmt == '*') {
2944                         if (!*str)
2945                                 break;
2946                         while (!isspace(*fmt) && *fmt != '%' && *fmt) {
2947                                 /* '%*[' not yet supported, invalid format */
2948                                 if (*fmt == '[')
2949                                         return num;
2950                                 fmt++;
2951                         }
2952                         while (!isspace(*str) && *str)
2953                                 str++;
2954                         continue;
2955                 }
2956 
2957                 /* get field width */
2958                 field_width = -1;
2959                 if (isdigit(*fmt)) {
2960                         field_width = skip_atoi(&fmt);
2961                         if (field_width <= 0)
2962                                 break;
2963                 }
2964 
2965                 /* get conversion qualifier */
2966                 qualifier = -1;
2967                 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2968                     *fmt == 'z') {
2969                         qualifier = *fmt++;
2970                         if (unlikely(qualifier == *fmt)) {
2971                                 if (qualifier == 'h') {
2972                                         qualifier = 'H';
2973                                         fmt++;
2974                                 } else if (qualifier == 'l') {
2975                                         qualifier = 'L';
2976                                         fmt++;
2977                                 }
2978                         }
2979                 }
2980 
2981                 if (!*fmt)
2982                         break;
2983 
2984                 if (*fmt == 'n') {
2985                         /* return number of characters read so far */
2986                         *va_arg(args, int *) = str - buf;
2987                         ++fmt;
2988                         continue;
2989                 }
2990 
2991                 if (!*str)
2992                         break;
2993 
2994                 base = 10;
2995                 is_sign = false;
2996 
2997                 switch (*fmt++) {
2998                 case 'c':
2999                 {
3000                         char *s = (char *)va_arg(args, char*);
3001                         if (field_width == -1)
3002                                 field_width = 1;
3003                         do {
3004                                 *s++ = *str++;
3005                         } while (--field_width > 0 && *str);
3006                         num++;
3007                 }
3008                 continue;
3009                 case 's':
3010                 {
3011                         char *s = (char *)va_arg(args, char *);
3012                         if (field_width == -1)
3013                                 field_width = SHRT_MAX;
3014                         /* first, skip leading white space in buffer */
3015                         str = skip_spaces(str);
3016 
3017                         /* now copy until next white space */
3018                         while (*str && !isspace(*str) && field_width--)
3019                                 *s++ = *str++;
3020                         *s = '\0';
3021                         num++;
3022                 }
3023                 continue;
3024                 /*
3025                  * Warning: This implementation of the '[' conversion specifier
3026                  * deviates from its glibc counterpart in the following ways:
3027                  * (1) It does NOT support ranges i.e. '-' is NOT a special
3028                  *     character
3029                  * (2) It cannot match the closing bracket ']' itself
3030                  * (3) A field width is required
3031                  * (4) '%*[' (discard matching input) is currently not supported
3032                  *
3033                  * Example usage:
3034                  * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3035                  *              buf1, buf2, buf3);
3036                  * if (ret < 3)
3037                  *    // etc..
3038                  */
3039                 case '[':
3040                 {
3041                         char *s = (char *)va_arg(args, char *);
3042                         DECLARE_BITMAP(set, 256) = {0};
3043                         unsigned int len = 0;
3044                         bool negate = (*fmt == '^');
3045 
3046                         /* field width is required */
3047                         if (field_width == -1)
3048                                 return num;
3049 
3050                         if (negate)
3051                                 ++fmt;
3052 
3053                         for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3054                                 set_bit((u8)*fmt, set);
3055 
3056                         /* no ']' or no character set found */
3057                         if (!*fmt || !len)
3058                                 return num;
3059                         ++fmt;
3060 
3061                         if (negate) {
3062                                 bitmap_complement(set, set, 256);
3063                                 /* exclude null '\0' byte */
3064                                 clear_bit(0, set);
3065                         }
3066 
3067                         /* match must be non-empty */
3068                         if (!test_bit((u8)*str, set))
3069                                 return num;
3070 
3071                         while (test_bit((u8)*str, set) && field_width--)
3072                                 *s++ = *str++;
3073                         *s = '\0';
3074                         ++num;
3075                 }
3076                 continue;
3077                 case 'o':
3078                         base = 8;
3079                         break;
3080                 case 'x':
3081                 case 'X':
3082                         base = 16;
3083                         break;
3084                 case 'i':
3085                         base = 0;
3086                 case 'd':
3087                         is_sign = true;
3088                 case 'u':
3089                         break;
3090                 case '%':
3091                         /* looking for '%' in str */
3092                         if (*str++ != '%')
3093                                 return num;
3094                         continue;
3095                 default:
3096                         /* invalid format; stop here */
3097                         return num;
3098                 }
3099 
3100                 /* have some sort of integer conversion.
3101                  * first, skip white space in buffer.
3102                  */
3103                 str = skip_spaces(str);
3104 
3105                 digit = *str;
3106                 if (is_sign && digit == '-')
3107                         digit = *(str + 1);
3108 
3109                 if (!digit
3110                     || (base == 16 && !isxdigit(digit))
3111                     || (base == 10 && !isdigit(digit))
3112                     || (base == 8 && (!isdigit(digit) || digit > '7'))
3113                     || (base == 0 && !isdigit(digit)))
3114                         break;
3115 
3116                 if (is_sign)
3117                         val.s = qualifier != 'L' ?
3118                                 simple_strtol(str, &next, base) :
3119                                 simple_strtoll(str, &next, base);
3120                 else
3121                         val.u = qualifier != 'L' ?
3122                                 simple_strtoul(str, &next, base) :
3123                                 simple_strtoull(str, &next, base);
3124 
3125                 if (field_width > 0 && next - str > field_width) {
3126                         if (base == 0)
3127                                 _parse_integer_fixup_radix(str, &base);
3128                         while (next - str > field_width) {
3129                                 if (is_sign)
3130                                         val.s = div_s64(val.s, base);
3131                                 else
3132                                         val.u = div_u64(val.u, base);
3133                                 --next;
3134                         }
3135                 }
3136 
3137                 switch (qualifier) {
3138                 case 'H':       /* that's 'hh' in format */
3139                         if (is_sign)
3140                                 *va_arg(args, signed char *) = val.s;
3141                         else
3142                                 *va_arg(args, unsigned char *) = val.u;
3143                         break;
3144                 case 'h':
3145                         if (is_sign)
3146                                 *va_arg(args, short *) = val.s;
3147                         else
3148                                 *va_arg(args, unsigned short *) = val.u;
3149                         break;
3150                 case 'l':
3151                         if (is_sign)
3152                                 *va_arg(args, long *) = val.s;
3153                         else
3154                                 *va_arg(args, unsigned long *) = val.u;
3155                         break;
3156                 case 'L':
3157                         if (is_sign)
3158                                 *va_arg(args, long long *) = val.s;
3159                         else
3160                                 *va_arg(args, unsigned long long *) = val.u;
3161                         break;
3162                 case 'z':
3163                         *va_arg(args, size_t *) = val.u;
3164                         break;
3165                 default:
3166                         if (is_sign)
3167                                 *va_arg(args, int *) = val.s;
3168                         else
3169                                 *va_arg(args, unsigned int *) = val.u;
3170                         break;
3171                 }
3172                 num++;
3173 
3174                 if (!next)
3175                         break;
3176                 str = next;
3177         }
3178 
3179         return num;
3180 }
3181 EXPORT_SYMBOL(vsscanf);
3182 
3183 /**
3184  * sscanf - Unformat a buffer into a list of arguments
3185  * @buf:        input buffer
3186  * @fmt:        formatting of buffer
3187  * @...:        resulting arguments
3188  */
3189 int sscanf(const char *buf, const char *fmt, ...)
3190 {
3191         va_list args;
3192         int i;
3193 
3194         va_start(args, fmt);
3195         i = vsscanf(buf, fmt, args);
3196         va_end(args);
3197 
3198         return i;
3199 }
3200 EXPORT_SYMBOL(sscanf);
3201 

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