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[thirdparty/linux.git] / lib / vsprintf.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/lib/vsprintf.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 */
7
8 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
9 /*
10 * Wirzenius wrote this portably, Torvalds fucked it up :-)
11 */
12
13 /*
14 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
15 * - changed to provide snprintf and vsnprintf functions
16 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
17 * - scnprintf and vscnprintf
18 */
19
20 #include <stdarg.h>
21 #include <linux/build_bug.h>
22 #include <linux/clk.h>
23 #include <linux/clk-provider.h>
24 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */
25 #include <linux/types.h>
26 #include <linux/string.h>
27 #include <linux/ctype.h>
28 #include <linux/kernel.h>
29 #include <linux/kallsyms.h>
30 #include <linux/math64.h>
31 #include <linux/uaccess.h>
32 #include <linux/ioport.h>
33 #include <linux/dcache.h>
34 #include <linux/cred.h>
35 #include <linux/rtc.h>
36 #include <linux/uuid.h>
37 #include <linux/of.h>
38 #include <net/addrconf.h>
39 #include <linux/siphash.h>
40 #include <linux/compiler.h>
41 #ifdef CONFIG_BLOCK
42 #include <linux/blkdev.h>
43 #endif
44
45 #include "../mm/internal.h" /* For the trace_print_flags arrays */
46
47 #include <asm/page.h> /* for PAGE_SIZE */
48 #include <asm/byteorder.h> /* cpu_to_le16 */
49
50 #include <linux/string_helpers.h>
51 #include "kstrtox.h"
52
53 /**
54 * simple_strtoull - convert a string to an unsigned long long
55 * @cp: The start of the string
56 * @endp: A pointer to the end of the parsed string will be placed here
57 * @base: The number base to use
58 *
59 * This function is obsolete. Please use kstrtoull instead.
60 */
61 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
62 {
63 unsigned long long result;
64 unsigned int rv;
65
66 cp = _parse_integer_fixup_radix(cp, &base);
67 rv = _parse_integer(cp, base, &result);
68 /* FIXME */
69 cp += (rv & ~KSTRTOX_OVERFLOW);
70
71 if (endp)
72 *endp = (char *)cp;
73
74 return result;
75 }
76 EXPORT_SYMBOL(simple_strtoull);
77
78 /**
79 * simple_strtoul - convert a string to an unsigned long
80 * @cp: The start of the string
81 * @endp: A pointer to the end of the parsed string will be placed here
82 * @base: The number base to use
83 *
84 * This function is obsolete. Please use kstrtoul instead.
85 */
86 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
87 {
88 return simple_strtoull(cp, endp, base);
89 }
90 EXPORT_SYMBOL(simple_strtoul);
91
92 /**
93 * simple_strtol - convert a string to a signed long
94 * @cp: The start of the string
95 * @endp: A pointer to the end of the parsed string will be placed here
96 * @base: The number base to use
97 *
98 * This function is obsolete. Please use kstrtol instead.
99 */
100 long simple_strtol(const char *cp, char **endp, unsigned int base)
101 {
102 if (*cp == '-')
103 return -simple_strtoul(cp + 1, endp, base);
104
105 return simple_strtoul(cp, endp, base);
106 }
107 EXPORT_SYMBOL(simple_strtol);
108
109 /**
110 * simple_strtoll - convert a string to a signed long long
111 * @cp: The start of the string
112 * @endp: A pointer to the end of the parsed string will be placed here
113 * @base: The number base to use
114 *
115 * This function is obsolete. Please use kstrtoll instead.
116 */
117 long long simple_strtoll(const char *cp, char **endp, unsigned int base)
118 {
119 if (*cp == '-')
120 return -simple_strtoull(cp + 1, endp, base);
121
122 return simple_strtoull(cp, endp, base);
123 }
124 EXPORT_SYMBOL(simple_strtoll);
125
126 static noinline_for_stack
127 int skip_atoi(const char **s)
128 {
129 int i = 0;
130
131 do {
132 i = i*10 + *((*s)++) - '0';
133 } while (isdigit(**s));
134
135 return i;
136 }
137
138 /*
139 * Decimal conversion is by far the most typical, and is used for
140 * /proc and /sys data. This directly impacts e.g. top performance
141 * with many processes running. We optimize it for speed by emitting
142 * two characters at a time, using a 200 byte lookup table. This
143 * roughly halves the number of multiplications compared to computing
144 * the digits one at a time. Implementation strongly inspired by the
145 * previous version, which in turn used ideas described at
146 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
147 * from the author, Douglas W. Jones).
148 *
149 * It turns out there is precisely one 26 bit fixed-point
150 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
151 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
152 * range happens to be somewhat larger (x <= 1073741898), but that's
153 * irrelevant for our purpose.
154 *
155 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
156 * need a 32x32->64 bit multiply, so we simply use the same constant.
157 *
158 * For dividing a number in the range [100, 10^4-1] by 100, there are
159 * several options. The simplest is (x * 0x147b) >> 19, which is valid
160 * for all x <= 43698.
161 */
162
163 static const u16 decpair[100] = {
164 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
165 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
166 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
167 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
168 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
169 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
170 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
171 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
172 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
173 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
174 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
175 #undef _
176 };
177
178 /*
179 * This will print a single '0' even if r == 0, since we would
180 * immediately jump to out_r where two 0s would be written but only
181 * one of them accounted for in buf. This is needed by ip4_string
182 * below. All other callers pass a non-zero value of r.
183 */
184 static noinline_for_stack
185 char *put_dec_trunc8(char *buf, unsigned r)
186 {
187 unsigned q;
188
189 /* 1 <= r < 10^8 */
190 if (r < 100)
191 goto out_r;
192
193 /* 100 <= r < 10^8 */
194 q = (r * (u64)0x28f5c29) >> 32;
195 *((u16 *)buf) = decpair[r - 100*q];
196 buf += 2;
197
198 /* 1 <= q < 10^6 */
199 if (q < 100)
200 goto out_q;
201
202 /* 100 <= q < 10^6 */
203 r = (q * (u64)0x28f5c29) >> 32;
204 *((u16 *)buf) = decpair[q - 100*r];
205 buf += 2;
206
207 /* 1 <= r < 10^4 */
208 if (r < 100)
209 goto out_r;
210
211 /* 100 <= r < 10^4 */
212 q = (r * 0x147b) >> 19;
213 *((u16 *)buf) = decpair[r - 100*q];
214 buf += 2;
215 out_q:
216 /* 1 <= q < 100 */
217 r = q;
218 out_r:
219 /* 1 <= r < 100 */
220 *((u16 *)buf) = decpair[r];
221 buf += r < 10 ? 1 : 2;
222 return buf;
223 }
224
225 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
226 static noinline_for_stack
227 char *put_dec_full8(char *buf, unsigned r)
228 {
229 unsigned q;
230
231 /* 0 <= r < 10^8 */
232 q = (r * (u64)0x28f5c29) >> 32;
233 *((u16 *)buf) = decpair[r - 100*q];
234 buf += 2;
235
236 /* 0 <= q < 10^6 */
237 r = (q * (u64)0x28f5c29) >> 32;
238 *((u16 *)buf) = decpair[q - 100*r];
239 buf += 2;
240
241 /* 0 <= r < 10^4 */
242 q = (r * 0x147b) >> 19;
243 *((u16 *)buf) = decpair[r - 100*q];
244 buf += 2;
245
246 /* 0 <= q < 100 */
247 *((u16 *)buf) = decpair[q];
248 buf += 2;
249 return buf;
250 }
251
252 static noinline_for_stack
253 char *put_dec(char *buf, unsigned long long n)
254 {
255 if (n >= 100*1000*1000)
256 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
257 /* 1 <= n <= 1.6e11 */
258 if (n >= 100*1000*1000)
259 buf = put_dec_full8(buf, do_div(n, 100*1000*1000));
260 /* 1 <= n < 1e8 */
261 return put_dec_trunc8(buf, n);
262 }
263
264 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
265
266 static void
267 put_dec_full4(char *buf, unsigned r)
268 {
269 unsigned q;
270
271 /* 0 <= r < 10^4 */
272 q = (r * 0x147b) >> 19;
273 *((u16 *)buf) = decpair[r - 100*q];
274 buf += 2;
275 /* 0 <= q < 100 */
276 *((u16 *)buf) = decpair[q];
277 }
278
279 /*
280 * Call put_dec_full4 on x % 10000, return x / 10000.
281 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
282 * holds for all x < 1,128,869,999. The largest value this
283 * helper will ever be asked to convert is 1,125,520,955.
284 * (second call in the put_dec code, assuming n is all-ones).
285 */
286 static noinline_for_stack
287 unsigned put_dec_helper4(char *buf, unsigned x)
288 {
289 uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43;
290
291 put_dec_full4(buf, x - q * 10000);
292 return q;
293 }
294
295 /* Based on code by Douglas W. Jones found at
296 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
297 * (with permission from the author).
298 * Performs no 64-bit division and hence should be fast on 32-bit machines.
299 */
300 static
301 char *put_dec(char *buf, unsigned long long n)
302 {
303 uint32_t d3, d2, d1, q, h;
304
305 if (n < 100*1000*1000)
306 return put_dec_trunc8(buf, n);
307
308 d1 = ((uint32_t)n >> 16); /* implicit "& 0xffff" */
309 h = (n >> 32);
310 d2 = (h ) & 0xffff;
311 d3 = (h >> 16); /* implicit "& 0xffff" */
312
313 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
314 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
315 q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff);
316 q = put_dec_helper4(buf, q);
317
318 q += 7671 * d3 + 9496 * d2 + 6 * d1;
319 q = put_dec_helper4(buf+4, q);
320
321 q += 4749 * d3 + 42 * d2;
322 q = put_dec_helper4(buf+8, q);
323
324 q += 281 * d3;
325 buf += 12;
326 if (q)
327 buf = put_dec_trunc8(buf, q);
328 else while (buf[-1] == '0')
329 --buf;
330
331 return buf;
332 }
333
334 #endif
335
336 /*
337 * Convert passed number to decimal string.
338 * Returns the length of string. On buffer overflow, returns 0.
339 *
340 * If speed is not important, use snprintf(). It's easy to read the code.
341 */
342 int num_to_str(char *buf, int size, unsigned long long num, unsigned int width)
343 {
344 /* put_dec requires 2-byte alignment of the buffer. */
345 char tmp[sizeof(num) * 3] __aligned(2);
346 int idx, len;
347
348 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
349 if (num <= 9) {
350 tmp[0] = '0' + num;
351 len = 1;
352 } else {
353 len = put_dec(tmp, num) - tmp;
354 }
355
356 if (len > size || width > size)
357 return 0;
358
359 if (width > len) {
360 width = width - len;
361 for (idx = 0; idx < width; idx++)
362 buf[idx] = ' ';
363 } else {
364 width = 0;
365 }
366
367 for (idx = 0; idx < len; ++idx)
368 buf[idx + width] = tmp[len - idx - 1];
369
370 return len + width;
371 }
372
373 #define SIGN 1 /* unsigned/signed, must be 1 */
374 #define LEFT 2 /* left justified */
375 #define PLUS 4 /* show plus */
376 #define SPACE 8 /* space if plus */
377 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
378 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
379 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
380
381 enum format_type {
382 FORMAT_TYPE_NONE, /* Just a string part */
383 FORMAT_TYPE_WIDTH,
384 FORMAT_TYPE_PRECISION,
385 FORMAT_TYPE_CHAR,
386 FORMAT_TYPE_STR,
387 FORMAT_TYPE_PTR,
388 FORMAT_TYPE_PERCENT_CHAR,
389 FORMAT_TYPE_INVALID,
390 FORMAT_TYPE_LONG_LONG,
391 FORMAT_TYPE_ULONG,
392 FORMAT_TYPE_LONG,
393 FORMAT_TYPE_UBYTE,
394 FORMAT_TYPE_BYTE,
395 FORMAT_TYPE_USHORT,
396 FORMAT_TYPE_SHORT,
397 FORMAT_TYPE_UINT,
398 FORMAT_TYPE_INT,
399 FORMAT_TYPE_SIZE_T,
400 FORMAT_TYPE_PTRDIFF
401 };
402
403 struct printf_spec {
404 unsigned int type:8; /* format_type enum */
405 signed int field_width:24; /* width of output field */
406 unsigned int flags:8; /* flags to number() */
407 unsigned int base:8; /* number base, 8, 10 or 16 only */
408 signed int precision:16; /* # of digits/chars */
409 } __packed;
410 static_assert(sizeof(struct printf_spec) == 8);
411
412 #define FIELD_WIDTH_MAX ((1 << 23) - 1)
413 #define PRECISION_MAX ((1 << 15) - 1)
414
415 static noinline_for_stack
416 char *number(char *buf, char *end, unsigned long long num,
417 struct printf_spec spec)
418 {
419 /* put_dec requires 2-byte alignment of the buffer. */
420 char tmp[3 * sizeof(num)] __aligned(2);
421 char sign;
422 char locase;
423 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
424 int i;
425 bool is_zero = num == 0LL;
426 int field_width = spec.field_width;
427 int precision = spec.precision;
428
429 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
430 * produces same digits or (maybe lowercased) letters */
431 locase = (spec.flags & SMALL);
432 if (spec.flags & LEFT)
433 spec.flags &= ~ZEROPAD;
434 sign = 0;
435 if (spec.flags & SIGN) {
436 if ((signed long long)num < 0) {
437 sign = '-';
438 num = -(signed long long)num;
439 field_width--;
440 } else if (spec.flags & PLUS) {
441 sign = '+';
442 field_width--;
443 } else if (spec.flags & SPACE) {
444 sign = ' ';
445 field_width--;
446 }
447 }
448 if (need_pfx) {
449 if (spec.base == 16)
450 field_width -= 2;
451 else if (!is_zero)
452 field_width--;
453 }
454
455 /* generate full string in tmp[], in reverse order */
456 i = 0;
457 if (num < spec.base)
458 tmp[i++] = hex_asc_upper[num] | locase;
459 else if (spec.base != 10) { /* 8 or 16 */
460 int mask = spec.base - 1;
461 int shift = 3;
462
463 if (spec.base == 16)
464 shift = 4;
465 do {
466 tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase);
467 num >>= shift;
468 } while (num);
469 } else { /* base 10 */
470 i = put_dec(tmp, num) - tmp;
471 }
472
473 /* printing 100 using %2d gives "100", not "00" */
474 if (i > precision)
475 precision = i;
476 /* leading space padding */
477 field_width -= precision;
478 if (!(spec.flags & (ZEROPAD | LEFT))) {
479 while (--field_width >= 0) {
480 if (buf < end)
481 *buf = ' ';
482 ++buf;
483 }
484 }
485 /* sign */
486 if (sign) {
487 if (buf < end)
488 *buf = sign;
489 ++buf;
490 }
491 /* "0x" / "0" prefix */
492 if (need_pfx) {
493 if (spec.base == 16 || !is_zero) {
494 if (buf < end)
495 *buf = '0';
496 ++buf;
497 }
498 if (spec.base == 16) {
499 if (buf < end)
500 *buf = ('X' | locase);
501 ++buf;
502 }
503 }
504 /* zero or space padding */
505 if (!(spec.flags & LEFT)) {
506 char c = ' ' + (spec.flags & ZEROPAD);
507 BUILD_BUG_ON(' ' + ZEROPAD != '0');
508 while (--field_width >= 0) {
509 if (buf < end)
510 *buf = c;
511 ++buf;
512 }
513 }
514 /* hmm even more zero padding? */
515 while (i <= --precision) {
516 if (buf < end)
517 *buf = '0';
518 ++buf;
519 }
520 /* actual digits of result */
521 while (--i >= 0) {
522 if (buf < end)
523 *buf = tmp[i];
524 ++buf;
525 }
526 /* trailing space padding */
527 while (--field_width >= 0) {
528 if (buf < end)
529 *buf = ' ';
530 ++buf;
531 }
532
533 return buf;
534 }
535
536 static noinline_for_stack
537 char *special_hex_number(char *buf, char *end, unsigned long long num, int size)
538 {
539 struct printf_spec spec;
540
541 spec.type = FORMAT_TYPE_PTR;
542 spec.field_width = 2 + 2 * size; /* 0x + hex */
543 spec.flags = SPECIAL | SMALL | ZEROPAD;
544 spec.base = 16;
545 spec.precision = -1;
546
547 return number(buf, end, num, spec);
548 }
549
550 static void move_right(char *buf, char *end, unsigned len, unsigned spaces)
551 {
552 size_t size;
553 if (buf >= end) /* nowhere to put anything */
554 return;
555 size = end - buf;
556 if (size <= spaces) {
557 memset(buf, ' ', size);
558 return;
559 }
560 if (len) {
561 if (len > size - spaces)
562 len = size - spaces;
563 memmove(buf + spaces, buf, len);
564 }
565 memset(buf, ' ', spaces);
566 }
567
568 /*
569 * Handle field width padding for a string.
570 * @buf: current buffer position
571 * @n: length of string
572 * @end: end of output buffer
573 * @spec: for field width and flags
574 * Returns: new buffer position after padding.
575 */
576 static noinline_for_stack
577 char *widen_string(char *buf, int n, char *end, struct printf_spec spec)
578 {
579 unsigned spaces;
580
581 if (likely(n >= spec.field_width))
582 return buf;
583 /* we want to pad the sucker */
584 spaces = spec.field_width - n;
585 if (!(spec.flags & LEFT)) {
586 move_right(buf - n, end, n, spaces);
587 return buf + spaces;
588 }
589 while (spaces--) {
590 if (buf < end)
591 *buf = ' ';
592 ++buf;
593 }
594 return buf;
595 }
596
597 /* Handle string from a well known address. */
598 static char *string_nocheck(char *buf, char *end, const char *s,
599 struct printf_spec spec)
600 {
601 int len = 0;
602 size_t lim = spec.precision;
603
604 while (lim--) {
605 char c = *s++;
606 if (!c)
607 break;
608 if (buf < end)
609 *buf = c;
610 ++buf;
611 ++len;
612 }
613 return widen_string(buf, len, end, spec);
614 }
615
616 /* Be careful: error messages must fit into the given buffer. */
617 static char *error_string(char *buf, char *end, const char *s,
618 struct printf_spec spec)
619 {
620 /*
621 * Hard limit to avoid a completely insane messages. It actually
622 * works pretty well because most error messages are in
623 * the many pointer format modifiers.
624 */
625 if (spec.precision == -1)
626 spec.precision = 2 * sizeof(void *);
627
628 return string_nocheck(buf, end, s, spec);
629 }
630
631 /*
632 * Do not call any complex external code here. Nested printk()/vsprintf()
633 * might cause infinite loops. Failures might break printk() and would
634 * be hard to debug.
635 */
636 static const char *check_pointer_msg(const void *ptr)
637 {
638 if (!ptr)
639 return "(null)";
640
641 if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr))
642 return "(efault)";
643
644 return NULL;
645 }
646
647 static int check_pointer(char **buf, char *end, const void *ptr,
648 struct printf_spec spec)
649 {
650 const char *err_msg;
651
652 err_msg = check_pointer_msg(ptr);
653 if (err_msg) {
654 *buf = error_string(*buf, end, err_msg, spec);
655 return -EFAULT;
656 }
657
658 return 0;
659 }
660
661 static noinline_for_stack
662 char *string(char *buf, char *end, const char *s,
663 struct printf_spec spec)
664 {
665 if (check_pointer(&buf, end, s, spec))
666 return buf;
667
668 return string_nocheck(buf, end, s, spec);
669 }
670
671 static char *pointer_string(char *buf, char *end,
672 const void *ptr,
673 struct printf_spec spec)
674 {
675 spec.base = 16;
676 spec.flags |= SMALL;
677 if (spec.field_width == -1) {
678 spec.field_width = 2 * sizeof(ptr);
679 spec.flags |= ZEROPAD;
680 }
681
682 return number(buf, end, (unsigned long int)ptr, spec);
683 }
684
685 /* Make pointers available for printing early in the boot sequence. */
686 static int debug_boot_weak_hash __ro_after_init;
687
688 static int __init debug_boot_weak_hash_enable(char *str)
689 {
690 debug_boot_weak_hash = 1;
691 pr_info("debug_boot_weak_hash enabled\n");
692 return 0;
693 }
694 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable);
695
696 static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key);
697 static siphash_key_t ptr_key __read_mostly;
698
699 static void enable_ptr_key_workfn(struct work_struct *work)
700 {
701 get_random_bytes(&ptr_key, sizeof(ptr_key));
702 /* Needs to run from preemptible context */
703 static_branch_disable(&not_filled_random_ptr_key);
704 }
705
706 static DECLARE_WORK(enable_ptr_key_work, enable_ptr_key_workfn);
707
708 static void fill_random_ptr_key(struct random_ready_callback *unused)
709 {
710 /* This may be in an interrupt handler. */
711 queue_work(system_unbound_wq, &enable_ptr_key_work);
712 }
713
714 static struct random_ready_callback random_ready = {
715 .func = fill_random_ptr_key
716 };
717
718 static int __init initialize_ptr_random(void)
719 {
720 int key_size = sizeof(ptr_key);
721 int ret;
722
723 /* Use hw RNG if available. */
724 if (get_random_bytes_arch(&ptr_key, key_size) == key_size) {
725 static_branch_disable(&not_filled_random_ptr_key);
726 return 0;
727 }
728
729 ret = add_random_ready_callback(&random_ready);
730 if (!ret) {
731 return 0;
732 } else if (ret == -EALREADY) {
733 /* This is in preemptible context */
734 enable_ptr_key_workfn(&enable_ptr_key_work);
735 return 0;
736 }
737
738 return ret;
739 }
740 early_initcall(initialize_ptr_random);
741
742 /* Maps a pointer to a 32 bit unique identifier. */
743 static char *ptr_to_id(char *buf, char *end, const void *ptr,
744 struct printf_spec spec)
745 {
746 const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)";
747 unsigned long hashval;
748
749 /* When debugging early boot use non-cryptographically secure hash. */
750 if (unlikely(debug_boot_weak_hash)) {
751 hashval = hash_long((unsigned long)ptr, 32);
752 return pointer_string(buf, end, (const void *)hashval, spec);
753 }
754
755 if (static_branch_unlikely(&not_filled_random_ptr_key)) {
756 spec.field_width = 2 * sizeof(ptr);
757 /* string length must be less than default_width */
758 return error_string(buf, end, str, spec);
759 }
760
761 #ifdef CONFIG_64BIT
762 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
763 /*
764 * Mask off the first 32 bits, this makes explicit that we have
765 * modified the address (and 32 bits is plenty for a unique ID).
766 */
767 hashval = hashval & 0xffffffff;
768 #else
769 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
770 #endif
771 return pointer_string(buf, end, (const void *)hashval, spec);
772 }
773
774 int kptr_restrict __read_mostly;
775
776 static noinline_for_stack
777 char *restricted_pointer(char *buf, char *end, const void *ptr,
778 struct printf_spec spec)
779 {
780 switch (kptr_restrict) {
781 case 0:
782 /* Handle as %p, hash and do _not_ leak addresses. */
783 return ptr_to_id(buf, end, ptr, spec);
784 case 1: {
785 const struct cred *cred;
786
787 /*
788 * kptr_restrict==1 cannot be used in IRQ context
789 * because its test for CAP_SYSLOG would be meaningless.
790 */
791 if (in_irq() || in_serving_softirq() || in_nmi()) {
792 if (spec.field_width == -1)
793 spec.field_width = 2 * sizeof(ptr);
794 return error_string(buf, end, "pK-error", spec);
795 }
796
797 /*
798 * Only print the real pointer value if the current
799 * process has CAP_SYSLOG and is running with the
800 * same credentials it started with. This is because
801 * access to files is checked at open() time, but %pK
802 * checks permission at read() time. We don't want to
803 * leak pointer values if a binary opens a file using
804 * %pK and then elevates privileges before reading it.
805 */
806 cred = current_cred();
807 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
808 !uid_eq(cred->euid, cred->uid) ||
809 !gid_eq(cred->egid, cred->gid))
810 ptr = NULL;
811 break;
812 }
813 case 2:
814 default:
815 /* Always print 0's for %pK */
816 ptr = NULL;
817 break;
818 }
819
820 return pointer_string(buf, end, ptr, spec);
821 }
822
823 static noinline_for_stack
824 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
825 const char *fmt)
826 {
827 const char *array[4], *s;
828 const struct dentry *p;
829 int depth;
830 int i, n;
831
832 switch (fmt[1]) {
833 case '2': case '3': case '4':
834 depth = fmt[1] - '0';
835 break;
836 default:
837 depth = 1;
838 }
839
840 rcu_read_lock();
841 for (i = 0; i < depth; i++, d = p) {
842 if (check_pointer(&buf, end, d, spec)) {
843 rcu_read_unlock();
844 return buf;
845 }
846
847 p = READ_ONCE(d->d_parent);
848 array[i] = READ_ONCE(d->d_name.name);
849 if (p == d) {
850 if (i)
851 array[i] = "";
852 i++;
853 break;
854 }
855 }
856 s = array[--i];
857 for (n = 0; n != spec.precision; n++, buf++) {
858 char c = *s++;
859 if (!c) {
860 if (!i)
861 break;
862 c = '/';
863 s = array[--i];
864 }
865 if (buf < end)
866 *buf = c;
867 }
868 rcu_read_unlock();
869 return widen_string(buf, n, end, spec);
870 }
871
872 #ifdef CONFIG_BLOCK
873 static noinline_for_stack
874 char *bdev_name(char *buf, char *end, struct block_device *bdev,
875 struct printf_spec spec, const char *fmt)
876 {
877 struct gendisk *hd;
878
879 if (check_pointer(&buf, end, bdev, spec))
880 return buf;
881
882 hd = bdev->bd_disk;
883 buf = string(buf, end, hd->disk_name, spec);
884 if (bdev->bd_part->partno) {
885 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
886 if (buf < end)
887 *buf = 'p';
888 buf++;
889 }
890 buf = number(buf, end, bdev->bd_part->partno, spec);
891 }
892 return buf;
893 }
894 #endif
895
896 static noinline_for_stack
897 char *symbol_string(char *buf, char *end, void *ptr,
898 struct printf_spec spec, const char *fmt)
899 {
900 unsigned long value;
901 #ifdef CONFIG_KALLSYMS
902 char sym[KSYM_SYMBOL_LEN];
903 #endif
904
905 if (fmt[1] == 'R')
906 ptr = __builtin_extract_return_addr(ptr);
907 value = (unsigned long)ptr;
908
909 #ifdef CONFIG_KALLSYMS
910 if (*fmt == 'B')
911 sprint_backtrace(sym, value);
912 else if (*fmt != 'f' && *fmt != 's')
913 sprint_symbol(sym, value);
914 else
915 sprint_symbol_no_offset(sym, value);
916
917 return string_nocheck(buf, end, sym, spec);
918 #else
919 return special_hex_number(buf, end, value, sizeof(void *));
920 #endif
921 }
922
923 static const struct printf_spec default_str_spec = {
924 .field_width = -1,
925 .precision = -1,
926 };
927
928 static const struct printf_spec default_flag_spec = {
929 .base = 16,
930 .precision = -1,
931 .flags = SPECIAL | SMALL,
932 };
933
934 static const struct printf_spec default_dec_spec = {
935 .base = 10,
936 .precision = -1,
937 };
938
939 static const struct printf_spec default_dec02_spec = {
940 .base = 10,
941 .field_width = 2,
942 .precision = -1,
943 .flags = ZEROPAD,
944 };
945
946 static const struct printf_spec default_dec04_spec = {
947 .base = 10,
948 .field_width = 4,
949 .precision = -1,
950 .flags = ZEROPAD,
951 };
952
953 static noinline_for_stack
954 char *resource_string(char *buf, char *end, struct resource *res,
955 struct printf_spec spec, const char *fmt)
956 {
957 #ifndef IO_RSRC_PRINTK_SIZE
958 #define IO_RSRC_PRINTK_SIZE 6
959 #endif
960
961 #ifndef MEM_RSRC_PRINTK_SIZE
962 #define MEM_RSRC_PRINTK_SIZE 10
963 #endif
964 static const struct printf_spec io_spec = {
965 .base = 16,
966 .field_width = IO_RSRC_PRINTK_SIZE,
967 .precision = -1,
968 .flags = SPECIAL | SMALL | ZEROPAD,
969 };
970 static const struct printf_spec mem_spec = {
971 .base = 16,
972 .field_width = MEM_RSRC_PRINTK_SIZE,
973 .precision = -1,
974 .flags = SPECIAL | SMALL | ZEROPAD,
975 };
976 static const struct printf_spec bus_spec = {
977 .base = 16,
978 .field_width = 2,
979 .precision = -1,
980 .flags = SMALL | ZEROPAD,
981 };
982 static const struct printf_spec str_spec = {
983 .field_width = -1,
984 .precision = 10,
985 .flags = LEFT,
986 };
987
988 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
989 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
990 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
991 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
992 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
993 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
994 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
995 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
996
997 char *p = sym, *pend = sym + sizeof(sym);
998 int decode = (fmt[0] == 'R') ? 1 : 0;
999 const struct printf_spec *specp;
1000
1001 if (check_pointer(&buf, end, res, spec))
1002 return buf;
1003
1004 *p++ = '[';
1005 if (res->flags & IORESOURCE_IO) {
1006 p = string_nocheck(p, pend, "io ", str_spec);
1007 specp = &io_spec;
1008 } else if (res->flags & IORESOURCE_MEM) {
1009 p = string_nocheck(p, pend, "mem ", str_spec);
1010 specp = &mem_spec;
1011 } else if (res->flags & IORESOURCE_IRQ) {
1012 p = string_nocheck(p, pend, "irq ", str_spec);
1013 specp = &default_dec_spec;
1014 } else if (res->flags & IORESOURCE_DMA) {
1015 p = string_nocheck(p, pend, "dma ", str_spec);
1016 specp = &default_dec_spec;
1017 } else if (res->flags & IORESOURCE_BUS) {
1018 p = string_nocheck(p, pend, "bus ", str_spec);
1019 specp = &bus_spec;
1020 } else {
1021 p = string_nocheck(p, pend, "??? ", str_spec);
1022 specp = &mem_spec;
1023 decode = 0;
1024 }
1025 if (decode && res->flags & IORESOURCE_UNSET) {
1026 p = string_nocheck(p, pend, "size ", str_spec);
1027 p = number(p, pend, resource_size(res), *specp);
1028 } else {
1029 p = number(p, pend, res->start, *specp);
1030 if (res->start != res->end) {
1031 *p++ = '-';
1032 p = number(p, pend, res->end, *specp);
1033 }
1034 }
1035 if (decode) {
1036 if (res->flags & IORESOURCE_MEM_64)
1037 p = string_nocheck(p, pend, " 64bit", str_spec);
1038 if (res->flags & IORESOURCE_PREFETCH)
1039 p = string_nocheck(p, pend, " pref", str_spec);
1040 if (res->flags & IORESOURCE_WINDOW)
1041 p = string_nocheck(p, pend, " window", str_spec);
1042 if (res->flags & IORESOURCE_DISABLED)
1043 p = string_nocheck(p, pend, " disabled", str_spec);
1044 } else {
1045 p = string_nocheck(p, pend, " flags ", str_spec);
1046 p = number(p, pend, res->flags, default_flag_spec);
1047 }
1048 *p++ = ']';
1049 *p = '\0';
1050
1051 return string_nocheck(buf, end, sym, spec);
1052 }
1053
1054 static noinline_for_stack
1055 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1056 const char *fmt)
1057 {
1058 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
1059 negative value, fallback to the default */
1060 char separator;
1061
1062 if (spec.field_width == 0)
1063 /* nothing to print */
1064 return buf;
1065
1066 if (check_pointer(&buf, end, addr, spec))
1067 return buf;
1068
1069 switch (fmt[1]) {
1070 case 'C':
1071 separator = ':';
1072 break;
1073 case 'D':
1074 separator = '-';
1075 break;
1076 case 'N':
1077 separator = 0;
1078 break;
1079 default:
1080 separator = ' ';
1081 break;
1082 }
1083
1084 if (spec.field_width > 0)
1085 len = min_t(int, spec.field_width, 64);
1086
1087 for (i = 0; i < len; ++i) {
1088 if (buf < end)
1089 *buf = hex_asc_hi(addr[i]);
1090 ++buf;
1091 if (buf < end)
1092 *buf = hex_asc_lo(addr[i]);
1093 ++buf;
1094
1095 if (separator && i != len - 1) {
1096 if (buf < end)
1097 *buf = separator;
1098 ++buf;
1099 }
1100 }
1101
1102 return buf;
1103 }
1104
1105 static noinline_for_stack
1106 char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
1107 struct printf_spec spec, const char *fmt)
1108 {
1109 const int CHUNKSZ = 32;
1110 int nr_bits = max_t(int, spec.field_width, 0);
1111 int i, chunksz;
1112 bool first = true;
1113
1114 if (check_pointer(&buf, end, bitmap, spec))
1115 return buf;
1116
1117 /* reused to print numbers */
1118 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
1119
1120 chunksz = nr_bits & (CHUNKSZ - 1);
1121 if (chunksz == 0)
1122 chunksz = CHUNKSZ;
1123
1124 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
1125 for (; i >= 0; i -= CHUNKSZ) {
1126 u32 chunkmask, val;
1127 int word, bit;
1128
1129 chunkmask = ((1ULL << chunksz) - 1);
1130 word = i / BITS_PER_LONG;
1131 bit = i % BITS_PER_LONG;
1132 val = (bitmap[word] >> bit) & chunkmask;
1133
1134 if (!first) {
1135 if (buf < end)
1136 *buf = ',';
1137 buf++;
1138 }
1139 first = false;
1140
1141 spec.field_width = DIV_ROUND_UP(chunksz, 4);
1142 buf = number(buf, end, val, spec);
1143
1144 chunksz = CHUNKSZ;
1145 }
1146 return buf;
1147 }
1148
1149 static noinline_for_stack
1150 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
1151 struct printf_spec spec, const char *fmt)
1152 {
1153 int nr_bits = max_t(int, spec.field_width, 0);
1154 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
1155 int cur, rbot, rtop;
1156 bool first = true;
1157
1158 if (check_pointer(&buf, end, bitmap, spec))
1159 return buf;
1160
1161 rbot = cur = find_first_bit(bitmap, nr_bits);
1162 while (cur < nr_bits) {
1163 rtop = cur;
1164 cur = find_next_bit(bitmap, nr_bits, cur + 1);
1165 if (cur < nr_bits && cur <= rtop + 1)
1166 continue;
1167
1168 if (!first) {
1169 if (buf < end)
1170 *buf = ',';
1171 buf++;
1172 }
1173 first = false;
1174
1175 buf = number(buf, end, rbot, default_dec_spec);
1176 if (rbot < rtop) {
1177 if (buf < end)
1178 *buf = '-';
1179 buf++;
1180
1181 buf = number(buf, end, rtop, default_dec_spec);
1182 }
1183
1184 rbot = cur;
1185 }
1186 return buf;
1187 }
1188
1189 static noinline_for_stack
1190 char *mac_address_string(char *buf, char *end, u8 *addr,
1191 struct printf_spec spec, const char *fmt)
1192 {
1193 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
1194 char *p = mac_addr;
1195 int i;
1196 char separator;
1197 bool reversed = false;
1198
1199 if (check_pointer(&buf, end, addr, spec))
1200 return buf;
1201
1202 switch (fmt[1]) {
1203 case 'F':
1204 separator = '-';
1205 break;
1206
1207 case 'R':
1208 reversed = true;
1209 /* fall through */
1210
1211 default:
1212 separator = ':';
1213 break;
1214 }
1215
1216 for (i = 0; i < 6; i++) {
1217 if (reversed)
1218 p = hex_byte_pack(p, addr[5 - i]);
1219 else
1220 p = hex_byte_pack(p, addr[i]);
1221
1222 if (fmt[0] == 'M' && i != 5)
1223 *p++ = separator;
1224 }
1225 *p = '\0';
1226
1227 return string_nocheck(buf, end, mac_addr, spec);
1228 }
1229
1230 static noinline_for_stack
1231 char *ip4_string(char *p, const u8 *addr, const char *fmt)
1232 {
1233 int i;
1234 bool leading_zeros = (fmt[0] == 'i');
1235 int index;
1236 int step;
1237
1238 switch (fmt[2]) {
1239 case 'h':
1240 #ifdef __BIG_ENDIAN
1241 index = 0;
1242 step = 1;
1243 #else
1244 index = 3;
1245 step = -1;
1246 #endif
1247 break;
1248 case 'l':
1249 index = 3;
1250 step = -1;
1251 break;
1252 case 'n':
1253 case 'b':
1254 default:
1255 index = 0;
1256 step = 1;
1257 break;
1258 }
1259 for (i = 0; i < 4; i++) {
1260 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1261 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1262 if (leading_zeros) {
1263 if (digits < 3)
1264 *p++ = '0';
1265 if (digits < 2)
1266 *p++ = '0';
1267 }
1268 /* reverse the digits in the quad */
1269 while (digits--)
1270 *p++ = temp[digits];
1271 if (i < 3)
1272 *p++ = '.';
1273 index += step;
1274 }
1275 *p = '\0';
1276
1277 return p;
1278 }
1279
1280 static noinline_for_stack
1281 char *ip6_compressed_string(char *p, const char *addr)
1282 {
1283 int i, j, range;
1284 unsigned char zerolength[8];
1285 int longest = 1;
1286 int colonpos = -1;
1287 u16 word;
1288 u8 hi, lo;
1289 bool needcolon = false;
1290 bool useIPv4;
1291 struct in6_addr in6;
1292
1293 memcpy(&in6, addr, sizeof(struct in6_addr));
1294
1295 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1296
1297 memset(zerolength, 0, sizeof(zerolength));
1298
1299 if (useIPv4)
1300 range = 6;
1301 else
1302 range = 8;
1303
1304 /* find position of longest 0 run */
1305 for (i = 0; i < range; i++) {
1306 for (j = i; j < range; j++) {
1307 if (in6.s6_addr16[j] != 0)
1308 break;
1309 zerolength[i]++;
1310 }
1311 }
1312 for (i = 0; i < range; i++) {
1313 if (zerolength[i] > longest) {
1314 longest = zerolength[i];
1315 colonpos = i;
1316 }
1317 }
1318 if (longest == 1) /* don't compress a single 0 */
1319 colonpos = -1;
1320
1321 /* emit address */
1322 for (i = 0; i < range; i++) {
1323 if (i == colonpos) {
1324 if (needcolon || i == 0)
1325 *p++ = ':';
1326 *p++ = ':';
1327 needcolon = false;
1328 i += longest - 1;
1329 continue;
1330 }
1331 if (needcolon) {
1332 *p++ = ':';
1333 needcolon = false;
1334 }
1335 /* hex u16 without leading 0s */
1336 word = ntohs(in6.s6_addr16[i]);
1337 hi = word >> 8;
1338 lo = word & 0xff;
1339 if (hi) {
1340 if (hi > 0x0f)
1341 p = hex_byte_pack(p, hi);
1342 else
1343 *p++ = hex_asc_lo(hi);
1344 p = hex_byte_pack(p, lo);
1345 }
1346 else if (lo > 0x0f)
1347 p = hex_byte_pack(p, lo);
1348 else
1349 *p++ = hex_asc_lo(lo);
1350 needcolon = true;
1351 }
1352
1353 if (useIPv4) {
1354 if (needcolon)
1355 *p++ = ':';
1356 p = ip4_string(p, &in6.s6_addr[12], "I4");
1357 }
1358 *p = '\0';
1359
1360 return p;
1361 }
1362
1363 static noinline_for_stack
1364 char *ip6_string(char *p, const char *addr, const char *fmt)
1365 {
1366 int i;
1367
1368 for (i = 0; i < 8; i++) {
1369 p = hex_byte_pack(p, *addr++);
1370 p = hex_byte_pack(p, *addr++);
1371 if (fmt[0] == 'I' && i != 7)
1372 *p++ = ':';
1373 }
1374 *p = '\0';
1375
1376 return p;
1377 }
1378
1379 static noinline_for_stack
1380 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1381 struct printf_spec spec, const char *fmt)
1382 {
1383 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1384
1385 if (fmt[0] == 'I' && fmt[2] == 'c')
1386 ip6_compressed_string(ip6_addr, addr);
1387 else
1388 ip6_string(ip6_addr, addr, fmt);
1389
1390 return string_nocheck(buf, end, ip6_addr, spec);
1391 }
1392
1393 static noinline_for_stack
1394 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1395 struct printf_spec spec, const char *fmt)
1396 {
1397 char ip4_addr[sizeof("255.255.255.255")];
1398
1399 ip4_string(ip4_addr, addr, fmt);
1400
1401 return string_nocheck(buf, end, ip4_addr, spec);
1402 }
1403
1404 static noinline_for_stack
1405 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1406 struct printf_spec spec, const char *fmt)
1407 {
1408 bool have_p = false, have_s = false, have_f = false, have_c = false;
1409 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1410 sizeof(":12345") + sizeof("/123456789") +
1411 sizeof("%1234567890")];
1412 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1413 const u8 *addr = (const u8 *) &sa->sin6_addr;
1414 char fmt6[2] = { fmt[0], '6' };
1415 u8 off = 0;
1416
1417 fmt++;
1418 while (isalpha(*++fmt)) {
1419 switch (*fmt) {
1420 case 'p':
1421 have_p = true;
1422 break;
1423 case 'f':
1424 have_f = true;
1425 break;
1426 case 's':
1427 have_s = true;
1428 break;
1429 case 'c':
1430 have_c = true;
1431 break;
1432 }
1433 }
1434
1435 if (have_p || have_s || have_f) {
1436 *p = '[';
1437 off = 1;
1438 }
1439
1440 if (fmt6[0] == 'I' && have_c)
1441 p = ip6_compressed_string(ip6_addr + off, addr);
1442 else
1443 p = ip6_string(ip6_addr + off, addr, fmt6);
1444
1445 if (have_p || have_s || have_f)
1446 *p++ = ']';
1447
1448 if (have_p) {
1449 *p++ = ':';
1450 p = number(p, pend, ntohs(sa->sin6_port), spec);
1451 }
1452 if (have_f) {
1453 *p++ = '/';
1454 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1455 IPV6_FLOWINFO_MASK), spec);
1456 }
1457 if (have_s) {
1458 *p++ = '%';
1459 p = number(p, pend, sa->sin6_scope_id, spec);
1460 }
1461 *p = '\0';
1462
1463 return string_nocheck(buf, end, ip6_addr, spec);
1464 }
1465
1466 static noinline_for_stack
1467 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1468 struct printf_spec spec, const char *fmt)
1469 {
1470 bool have_p = false;
1471 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1472 char *pend = ip4_addr + sizeof(ip4_addr);
1473 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1474 char fmt4[3] = { fmt[0], '4', 0 };
1475
1476 fmt++;
1477 while (isalpha(*++fmt)) {
1478 switch (*fmt) {
1479 case 'p':
1480 have_p = true;
1481 break;
1482 case 'h':
1483 case 'l':
1484 case 'n':
1485 case 'b':
1486 fmt4[2] = *fmt;
1487 break;
1488 }
1489 }
1490
1491 p = ip4_string(ip4_addr, addr, fmt4);
1492 if (have_p) {
1493 *p++ = ':';
1494 p = number(p, pend, ntohs(sa->sin_port), spec);
1495 }
1496 *p = '\0';
1497
1498 return string_nocheck(buf, end, ip4_addr, spec);
1499 }
1500
1501 static noinline_for_stack
1502 char *ip_addr_string(char *buf, char *end, const void *ptr,
1503 struct printf_spec spec, const char *fmt)
1504 {
1505 char *err_fmt_msg;
1506
1507 if (check_pointer(&buf, end, ptr, spec))
1508 return buf;
1509
1510 switch (fmt[1]) {
1511 case '6':
1512 return ip6_addr_string(buf, end, ptr, spec, fmt);
1513 case '4':
1514 return ip4_addr_string(buf, end, ptr, spec, fmt);
1515 case 'S': {
1516 const union {
1517 struct sockaddr raw;
1518 struct sockaddr_in v4;
1519 struct sockaddr_in6 v6;
1520 } *sa = ptr;
1521
1522 switch (sa->raw.sa_family) {
1523 case AF_INET:
1524 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1525 case AF_INET6:
1526 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1527 default:
1528 return error_string(buf, end, "(einval)", spec);
1529 }}
1530 }
1531
1532 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
1533 return error_string(buf, end, err_fmt_msg, spec);
1534 }
1535
1536 static noinline_for_stack
1537 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1538 const char *fmt)
1539 {
1540 bool found = true;
1541 int count = 1;
1542 unsigned int flags = 0;
1543 int len;
1544
1545 if (spec.field_width == 0)
1546 return buf; /* nothing to print */
1547
1548 if (check_pointer(&buf, end, addr, spec))
1549 return buf;
1550
1551 do {
1552 switch (fmt[count++]) {
1553 case 'a':
1554 flags |= ESCAPE_ANY;
1555 break;
1556 case 'c':
1557 flags |= ESCAPE_SPECIAL;
1558 break;
1559 case 'h':
1560 flags |= ESCAPE_HEX;
1561 break;
1562 case 'n':
1563 flags |= ESCAPE_NULL;
1564 break;
1565 case 'o':
1566 flags |= ESCAPE_OCTAL;
1567 break;
1568 case 'p':
1569 flags |= ESCAPE_NP;
1570 break;
1571 case 's':
1572 flags |= ESCAPE_SPACE;
1573 break;
1574 default:
1575 found = false;
1576 break;
1577 }
1578 } while (found);
1579
1580 if (!flags)
1581 flags = ESCAPE_ANY_NP;
1582
1583 len = spec.field_width < 0 ? 1 : spec.field_width;
1584
1585 /*
1586 * string_escape_mem() writes as many characters as it can to
1587 * the given buffer, and returns the total size of the output
1588 * had the buffer been big enough.
1589 */
1590 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1591
1592 return buf;
1593 }
1594
1595 static char *va_format(char *buf, char *end, struct va_format *va_fmt,
1596 struct printf_spec spec, const char *fmt)
1597 {
1598 va_list va;
1599
1600 if (check_pointer(&buf, end, va_fmt, spec))
1601 return buf;
1602
1603 va_copy(va, *va_fmt->va);
1604 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
1605 va_end(va);
1606
1607 return buf;
1608 }
1609
1610 static noinline_for_stack
1611 char *uuid_string(char *buf, char *end, const u8 *addr,
1612 struct printf_spec spec, const char *fmt)
1613 {
1614 char uuid[UUID_STRING_LEN + 1];
1615 char *p = uuid;
1616 int i;
1617 const u8 *index = uuid_index;
1618 bool uc = false;
1619
1620 if (check_pointer(&buf, end, addr, spec))
1621 return buf;
1622
1623 switch (*(++fmt)) {
1624 case 'L':
1625 uc = true; /* fall-through */
1626 case 'l':
1627 index = guid_index;
1628 break;
1629 case 'B':
1630 uc = true;
1631 break;
1632 }
1633
1634 for (i = 0; i < 16; i++) {
1635 if (uc)
1636 p = hex_byte_pack_upper(p, addr[index[i]]);
1637 else
1638 p = hex_byte_pack(p, addr[index[i]]);
1639 switch (i) {
1640 case 3:
1641 case 5:
1642 case 7:
1643 case 9:
1644 *p++ = '-';
1645 break;
1646 }
1647 }
1648
1649 *p = 0;
1650
1651 return string_nocheck(buf, end, uuid, spec);
1652 }
1653
1654 static noinline_for_stack
1655 char *netdev_bits(char *buf, char *end, const void *addr,
1656 struct printf_spec spec, const char *fmt)
1657 {
1658 unsigned long long num;
1659 int size;
1660
1661 if (check_pointer(&buf, end, addr, spec))
1662 return buf;
1663
1664 switch (fmt[1]) {
1665 case 'F':
1666 num = *(const netdev_features_t *)addr;
1667 size = sizeof(netdev_features_t);
1668 break;
1669 default:
1670 return error_string(buf, end, "(%pN?)", spec);
1671 }
1672
1673 return special_hex_number(buf, end, num, size);
1674 }
1675
1676 static noinline_for_stack
1677 char *address_val(char *buf, char *end, const void *addr,
1678 struct printf_spec spec, const char *fmt)
1679 {
1680 unsigned long long num;
1681 int size;
1682
1683 if (check_pointer(&buf, end, addr, spec))
1684 return buf;
1685
1686 switch (fmt[1]) {
1687 case 'd':
1688 num = *(const dma_addr_t *)addr;
1689 size = sizeof(dma_addr_t);
1690 break;
1691 case 'p':
1692 default:
1693 num = *(const phys_addr_t *)addr;
1694 size = sizeof(phys_addr_t);
1695 break;
1696 }
1697
1698 return special_hex_number(buf, end, num, size);
1699 }
1700
1701 static noinline_for_stack
1702 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1703 {
1704 int year = tm->tm_year + (r ? 0 : 1900);
1705 int mon = tm->tm_mon + (r ? 0 : 1);
1706
1707 buf = number(buf, end, year, default_dec04_spec);
1708 if (buf < end)
1709 *buf = '-';
1710 buf++;
1711
1712 buf = number(buf, end, mon, default_dec02_spec);
1713 if (buf < end)
1714 *buf = '-';
1715 buf++;
1716
1717 return number(buf, end, tm->tm_mday, default_dec02_spec);
1718 }
1719
1720 static noinline_for_stack
1721 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1722 {
1723 buf = number(buf, end, tm->tm_hour, default_dec02_spec);
1724 if (buf < end)
1725 *buf = ':';
1726 buf++;
1727
1728 buf = number(buf, end, tm->tm_min, default_dec02_spec);
1729 if (buf < end)
1730 *buf = ':';
1731 buf++;
1732
1733 return number(buf, end, tm->tm_sec, default_dec02_spec);
1734 }
1735
1736 static noinline_for_stack
1737 char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
1738 struct printf_spec spec, const char *fmt)
1739 {
1740 bool have_t = true, have_d = true;
1741 bool raw = false;
1742 int count = 2;
1743
1744 if (check_pointer(&buf, end, tm, spec))
1745 return buf;
1746
1747 switch (fmt[count]) {
1748 case 'd':
1749 have_t = false;
1750 count++;
1751 break;
1752 case 't':
1753 have_d = false;
1754 count++;
1755 break;
1756 }
1757
1758 raw = fmt[count] == 'r';
1759
1760 if (have_d)
1761 buf = date_str(buf, end, tm, raw);
1762 if (have_d && have_t) {
1763 /* Respect ISO 8601 */
1764 if (buf < end)
1765 *buf = 'T';
1766 buf++;
1767 }
1768 if (have_t)
1769 buf = time_str(buf, end, tm, raw);
1770
1771 return buf;
1772 }
1773
1774 static noinline_for_stack
1775 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
1776 const char *fmt)
1777 {
1778 switch (fmt[1]) {
1779 case 'R':
1780 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
1781 default:
1782 return error_string(buf, end, "(%ptR?)", spec);
1783 }
1784 }
1785
1786 static noinline_for_stack
1787 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1788 const char *fmt)
1789 {
1790 if (!IS_ENABLED(CONFIG_HAVE_CLK))
1791 return error_string(buf, end, "(%pC?)", spec);
1792
1793 if (check_pointer(&buf, end, clk, spec))
1794 return buf;
1795
1796 switch (fmt[1]) {
1797 case 'n':
1798 default:
1799 #ifdef CONFIG_COMMON_CLK
1800 return string(buf, end, __clk_get_name(clk), spec);
1801 #else
1802 return error_string(buf, end, "(%pC?)", spec);
1803 #endif
1804 }
1805 }
1806
1807 static
1808 char *format_flags(char *buf, char *end, unsigned long flags,
1809 const struct trace_print_flags *names)
1810 {
1811 unsigned long mask;
1812
1813 for ( ; flags && names->name; names++) {
1814 mask = names->mask;
1815 if ((flags & mask) != mask)
1816 continue;
1817
1818 buf = string(buf, end, names->name, default_str_spec);
1819
1820 flags &= ~mask;
1821 if (flags) {
1822 if (buf < end)
1823 *buf = '|';
1824 buf++;
1825 }
1826 }
1827
1828 if (flags)
1829 buf = number(buf, end, flags, default_flag_spec);
1830
1831 return buf;
1832 }
1833
1834 static noinline_for_stack
1835 char *flags_string(char *buf, char *end, void *flags_ptr,
1836 struct printf_spec spec, const char *fmt)
1837 {
1838 unsigned long flags;
1839 const struct trace_print_flags *names;
1840
1841 if (check_pointer(&buf, end, flags_ptr, spec))
1842 return buf;
1843
1844 switch (fmt[1]) {
1845 case 'p':
1846 flags = *(unsigned long *)flags_ptr;
1847 /* Remove zone id */
1848 flags &= (1UL << NR_PAGEFLAGS) - 1;
1849 names = pageflag_names;
1850 break;
1851 case 'v':
1852 flags = *(unsigned long *)flags_ptr;
1853 names = vmaflag_names;
1854 break;
1855 case 'g':
1856 flags = *(gfp_t *)flags_ptr;
1857 names = gfpflag_names;
1858 break;
1859 default:
1860 return error_string(buf, end, "(%pG?)", spec);
1861 }
1862
1863 return format_flags(buf, end, flags, names);
1864 }
1865
1866 static const char *device_node_name_for_depth(const struct device_node *np, int depth)
1867 {
1868 for ( ; np && depth; depth--)
1869 np = np->parent;
1870
1871 return kbasename(np->full_name);
1872 }
1873
1874 static noinline_for_stack
1875 char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end)
1876 {
1877 int depth;
1878 const struct device_node *parent = np->parent;
1879
1880 /* special case for root node */
1881 if (!parent)
1882 return string_nocheck(buf, end, "/", default_str_spec);
1883
1884 for (depth = 0; parent->parent; depth++)
1885 parent = parent->parent;
1886
1887 for ( ; depth >= 0; depth--) {
1888 buf = string_nocheck(buf, end, "/", default_str_spec);
1889 buf = string(buf, end, device_node_name_for_depth(np, depth),
1890 default_str_spec);
1891 }
1892 return buf;
1893 }
1894
1895 static noinline_for_stack
1896 char *device_node_string(char *buf, char *end, struct device_node *dn,
1897 struct printf_spec spec, const char *fmt)
1898 {
1899 char tbuf[sizeof("xxxx") + 1];
1900 const char *p;
1901 int ret;
1902 char *buf_start = buf;
1903 struct property *prop;
1904 bool has_mult, pass;
1905 static const struct printf_spec num_spec = {
1906 .flags = SMALL,
1907 .field_width = -1,
1908 .precision = -1,
1909 .base = 10,
1910 };
1911
1912 struct printf_spec str_spec = spec;
1913 str_spec.field_width = -1;
1914
1915 if (!IS_ENABLED(CONFIG_OF))
1916 return error_string(buf, end, "(%pOF?)", spec);
1917
1918 if (check_pointer(&buf, end, dn, spec))
1919 return buf;
1920
1921 /* simple case without anything any more format specifiers */
1922 fmt++;
1923 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
1924 fmt = "f";
1925
1926 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
1927 int precision;
1928 if (pass) {
1929 if (buf < end)
1930 *buf = ':';
1931 buf++;
1932 }
1933
1934 switch (*fmt) {
1935 case 'f': /* full_name */
1936 buf = device_node_gen_full_name(dn, buf, end);
1937 break;
1938 case 'n': /* name */
1939 p = kbasename(of_node_full_name(dn));
1940 precision = str_spec.precision;
1941 str_spec.precision = strchrnul(p, '@') - p;
1942 buf = string(buf, end, p, str_spec);
1943 str_spec.precision = precision;
1944 break;
1945 case 'p': /* phandle */
1946 buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
1947 break;
1948 case 'P': /* path-spec */
1949 p = kbasename(of_node_full_name(dn));
1950 if (!p[1])
1951 p = "/";
1952 buf = string(buf, end, p, str_spec);
1953 break;
1954 case 'F': /* flags */
1955 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
1956 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
1957 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
1958 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
1959 tbuf[4] = 0;
1960 buf = string_nocheck(buf, end, tbuf, str_spec);
1961 break;
1962 case 'c': /* major compatible string */
1963 ret = of_property_read_string(dn, "compatible", &p);
1964 if (!ret)
1965 buf = string(buf, end, p, str_spec);
1966 break;
1967 case 'C': /* full compatible string */
1968 has_mult = false;
1969 of_property_for_each_string(dn, "compatible", prop, p) {
1970 if (has_mult)
1971 buf = string_nocheck(buf, end, ",", str_spec);
1972 buf = string_nocheck(buf, end, "\"", str_spec);
1973 buf = string(buf, end, p, str_spec);
1974 buf = string_nocheck(buf, end, "\"", str_spec);
1975
1976 has_mult = true;
1977 }
1978 break;
1979 default:
1980 break;
1981 }
1982 }
1983
1984 return widen_string(buf, buf - buf_start, end, spec);
1985 }
1986
1987 static char *kobject_string(char *buf, char *end, void *ptr,
1988 struct printf_spec spec, const char *fmt)
1989 {
1990 switch (fmt[1]) {
1991 case 'F':
1992 return device_node_string(buf, end, ptr, spec, fmt + 1);
1993 }
1994
1995 return error_string(buf, end, "(%pO?)", spec);
1996 }
1997
1998 /*
1999 * Show a '%p' thing. A kernel extension is that the '%p' is followed
2000 * by an extra set of alphanumeric characters that are extended format
2001 * specifiers.
2002 *
2003 * Please update scripts/checkpatch.pl when adding/removing conversion
2004 * characters. (Search for "check for vsprintf extension").
2005 *
2006 * Right now we handle:
2007 *
2008 * - 'S' For symbolic direct pointers (or function descriptors) with offset
2009 * - 's' For symbolic direct pointers (or function descriptors) without offset
2010 * - 'F' Same as 'S'
2011 * - 'f' Same as 's'
2012 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
2013 * - 'B' For backtraced symbolic direct pointers with offset
2014 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
2015 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
2016 * - 'b[l]' For a bitmap, the number of bits is determined by the field
2017 * width which must be explicitly specified either as part of the
2018 * format string '%32b[l]' or through '%*b[l]', [l] selects
2019 * range-list format instead of hex format
2020 * - 'M' For a 6-byte MAC address, it prints the address in the
2021 * usual colon-separated hex notation
2022 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
2023 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
2024 * with a dash-separated hex notation
2025 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
2026 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
2027 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
2028 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
2029 * [S][pfs]
2030 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2031 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2032 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
2033 * IPv6 omits the colons (01020304...0f)
2034 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
2035 * [S][pfs]
2036 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2037 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2038 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
2039 * - 'I[6S]c' for IPv6 addresses printed as specified by
2040 * http://tools.ietf.org/html/rfc5952
2041 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
2042 * of the following flags (see string_escape_mem() for the
2043 * details):
2044 * a - ESCAPE_ANY
2045 * c - ESCAPE_SPECIAL
2046 * h - ESCAPE_HEX
2047 * n - ESCAPE_NULL
2048 * o - ESCAPE_OCTAL
2049 * p - ESCAPE_NP
2050 * s - ESCAPE_SPACE
2051 * By default ESCAPE_ANY_NP is used.
2052 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
2053 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
2054 * Options for %pU are:
2055 * b big endian lower case hex (default)
2056 * B big endian UPPER case hex
2057 * l little endian lower case hex
2058 * L little endian UPPER case hex
2059 * big endian output byte order is:
2060 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
2061 * little endian output byte order is:
2062 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
2063 * - 'V' For a struct va_format which contains a format string * and va_list *,
2064 * call vsnprintf(->format, *->va_list).
2065 * Implements a "recursive vsnprintf".
2066 * Do not use this feature without some mechanism to verify the
2067 * correctness of the format string and va_list arguments.
2068 * - 'K' For a kernel pointer that should be hidden from unprivileged users
2069 * - 'NF' For a netdev_features_t
2070 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
2071 * a certain separator (' ' by default):
2072 * C colon
2073 * D dash
2074 * N no separator
2075 * The maximum supported length is 64 bytes of the input. Consider
2076 * to use print_hex_dump() for the larger input.
2077 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
2078 * (default assumed to be phys_addr_t, passed by reference)
2079 * - 'd[234]' For a dentry name (optionally 2-4 last components)
2080 * - 'D[234]' Same as 'd' but for a struct file
2081 * - 'g' For block_device name (gendisk + partition number)
2082 * - 't[R][dt][r]' For time and date as represented:
2083 * R struct rtc_time
2084 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
2085 * (legacy clock framework) of the clock
2086 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
2087 * (legacy clock framework) of the clock
2088 * - 'G' For flags to be printed as a collection of symbolic strings that would
2089 * construct the specific value. Supported flags given by option:
2090 * p page flags (see struct page) given as pointer to unsigned long
2091 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
2092 * v vma flags (VM_*) given as pointer to unsigned long
2093 * - 'OF[fnpPcCF]' For a device tree object
2094 * Without any optional arguments prints the full_name
2095 * f device node full_name
2096 * n device node name
2097 * p device node phandle
2098 * P device node path spec (name + @unit)
2099 * F device node flags
2100 * c major compatible string
2101 * C full compatible string
2102 * - 'x' For printing the address. Equivalent to "%lx".
2103 *
2104 * ** When making changes please also update:
2105 * Documentation/core-api/printk-formats.rst
2106 *
2107 * Note: The default behaviour (unadorned %p) is to hash the address,
2108 * rendering it useful as a unique identifier.
2109 */
2110 static noinline_for_stack
2111 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
2112 struct printf_spec spec)
2113 {
2114 switch (*fmt) {
2115 case 'F':
2116 case 'f':
2117 case 'S':
2118 case 's':
2119 ptr = dereference_symbol_descriptor(ptr);
2120 /* Fallthrough */
2121 case 'B':
2122 return symbol_string(buf, end, ptr, spec, fmt);
2123 case 'R':
2124 case 'r':
2125 return resource_string(buf, end, ptr, spec, fmt);
2126 case 'h':
2127 return hex_string(buf, end, ptr, spec, fmt);
2128 case 'b':
2129 switch (fmt[1]) {
2130 case 'l':
2131 return bitmap_list_string(buf, end, ptr, spec, fmt);
2132 default:
2133 return bitmap_string(buf, end, ptr, spec, fmt);
2134 }
2135 case 'M': /* Colon separated: 00:01:02:03:04:05 */
2136 case 'm': /* Contiguous: 000102030405 */
2137 /* [mM]F (FDDI) */
2138 /* [mM]R (Reverse order; Bluetooth) */
2139 return mac_address_string(buf, end, ptr, spec, fmt);
2140 case 'I': /* Formatted IP supported
2141 * 4: 1.2.3.4
2142 * 6: 0001:0203:...:0708
2143 * 6c: 1::708 or 1::1.2.3.4
2144 */
2145 case 'i': /* Contiguous:
2146 * 4: 001.002.003.004
2147 * 6: 000102...0f
2148 */
2149 return ip_addr_string(buf, end, ptr, spec, fmt);
2150 case 'E':
2151 return escaped_string(buf, end, ptr, spec, fmt);
2152 case 'U':
2153 return uuid_string(buf, end, ptr, spec, fmt);
2154 case 'V':
2155 return va_format(buf, end, ptr, spec, fmt);
2156 case 'K':
2157 return restricted_pointer(buf, end, ptr, spec);
2158 case 'N':
2159 return netdev_bits(buf, end, ptr, spec, fmt);
2160 case 'a':
2161 return address_val(buf, end, ptr, spec, fmt);
2162 case 'd':
2163 return dentry_name(buf, end, ptr, spec, fmt);
2164 case 't':
2165 return time_and_date(buf, end, ptr, spec, fmt);
2166 case 'C':
2167 return clock(buf, end, ptr, spec, fmt);
2168 case 'D':
2169 return dentry_name(buf, end,
2170 ((const struct file *)ptr)->f_path.dentry,
2171 spec, fmt);
2172 #ifdef CONFIG_BLOCK
2173 case 'g':
2174 return bdev_name(buf, end, ptr, spec, fmt);
2175 #endif
2176
2177 case 'G':
2178 return flags_string(buf, end, ptr, spec, fmt);
2179 case 'O':
2180 return kobject_string(buf, end, ptr, spec, fmt);
2181 case 'x':
2182 return pointer_string(buf, end, ptr, spec);
2183 }
2184
2185 /* default is to _not_ leak addresses, hash before printing */
2186 return ptr_to_id(buf, end, ptr, spec);
2187 }
2188
2189 /*
2190 * Helper function to decode printf style format.
2191 * Each call decode a token from the format and return the
2192 * number of characters read (or likely the delta where it wants
2193 * to go on the next call).
2194 * The decoded token is returned through the parameters
2195 *
2196 * 'h', 'l', or 'L' for integer fields
2197 * 'z' support added 23/7/1999 S.H.
2198 * 'z' changed to 'Z' --davidm 1/25/99
2199 * 'Z' changed to 'z' --adobriyan 2017-01-25
2200 * 't' added for ptrdiff_t
2201 *
2202 * @fmt: the format string
2203 * @type of the token returned
2204 * @flags: various flags such as +, -, # tokens..
2205 * @field_width: overwritten width
2206 * @base: base of the number (octal, hex, ...)
2207 * @precision: precision of a number
2208 * @qualifier: qualifier of a number (long, size_t, ...)
2209 */
2210 static noinline_for_stack
2211 int format_decode(const char *fmt, struct printf_spec *spec)
2212 {
2213 const char *start = fmt;
2214 char qualifier;
2215
2216 /* we finished early by reading the field width */
2217 if (spec->type == FORMAT_TYPE_WIDTH) {
2218 if (spec->field_width < 0) {
2219 spec->field_width = -spec->field_width;
2220 spec->flags |= LEFT;
2221 }
2222 spec->type = FORMAT_TYPE_NONE;
2223 goto precision;
2224 }
2225
2226 /* we finished early by reading the precision */
2227 if (spec->type == FORMAT_TYPE_PRECISION) {
2228 if (spec->precision < 0)
2229 spec->precision = 0;
2230
2231 spec->type = FORMAT_TYPE_NONE;
2232 goto qualifier;
2233 }
2234
2235 /* By default */
2236 spec->type = FORMAT_TYPE_NONE;
2237
2238 for (; *fmt ; ++fmt) {
2239 if (*fmt == '%')
2240 break;
2241 }
2242
2243 /* Return the current non-format string */
2244 if (fmt != start || !*fmt)
2245 return fmt - start;
2246
2247 /* Process flags */
2248 spec->flags = 0;
2249
2250 while (1) { /* this also skips first '%' */
2251 bool found = true;
2252
2253 ++fmt;
2254
2255 switch (*fmt) {
2256 case '-': spec->flags |= LEFT; break;
2257 case '+': spec->flags |= PLUS; break;
2258 case ' ': spec->flags |= SPACE; break;
2259 case '#': spec->flags |= SPECIAL; break;
2260 case '0': spec->flags |= ZEROPAD; break;
2261 default: found = false;
2262 }
2263
2264 if (!found)
2265 break;
2266 }
2267
2268 /* get field width */
2269 spec->field_width = -1;
2270
2271 if (isdigit(*fmt))
2272 spec->field_width = skip_atoi(&fmt);
2273 else if (*fmt == '*') {
2274 /* it's the next argument */
2275 spec->type = FORMAT_TYPE_WIDTH;
2276 return ++fmt - start;
2277 }
2278
2279 precision:
2280 /* get the precision */
2281 spec->precision = -1;
2282 if (*fmt == '.') {
2283 ++fmt;
2284 if (isdigit(*fmt)) {
2285 spec->precision = skip_atoi(&fmt);
2286 if (spec->precision < 0)
2287 spec->precision = 0;
2288 } else if (*fmt == '*') {
2289 /* it's the next argument */
2290 spec->type = FORMAT_TYPE_PRECISION;
2291 return ++fmt - start;
2292 }
2293 }
2294
2295 qualifier:
2296 /* get the conversion qualifier */
2297 qualifier = 0;
2298 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2299 *fmt == 'z' || *fmt == 't') {
2300 qualifier = *fmt++;
2301 if (unlikely(qualifier == *fmt)) {
2302 if (qualifier == 'l') {
2303 qualifier = 'L';
2304 ++fmt;
2305 } else if (qualifier == 'h') {
2306 qualifier = 'H';
2307 ++fmt;
2308 }
2309 }
2310 }
2311
2312 /* default base */
2313 spec->base = 10;
2314 switch (*fmt) {
2315 case 'c':
2316 spec->type = FORMAT_TYPE_CHAR;
2317 return ++fmt - start;
2318
2319 case 's':
2320 spec->type = FORMAT_TYPE_STR;
2321 return ++fmt - start;
2322
2323 case 'p':
2324 spec->type = FORMAT_TYPE_PTR;
2325 return ++fmt - start;
2326
2327 case '%':
2328 spec->type = FORMAT_TYPE_PERCENT_CHAR;
2329 return ++fmt - start;
2330
2331 /* integer number formats - set up the flags and "break" */
2332 case 'o':
2333 spec->base = 8;
2334 break;
2335
2336 case 'x':
2337 spec->flags |= SMALL;
2338 /* fall through */
2339
2340 case 'X':
2341 spec->base = 16;
2342 break;
2343
2344 case 'd':
2345 case 'i':
2346 spec->flags |= SIGN;
2347 case 'u':
2348 break;
2349
2350 case 'n':
2351 /*
2352 * Since %n poses a greater security risk than
2353 * utility, treat it as any other invalid or
2354 * unsupported format specifier.
2355 */
2356 /* Fall-through */
2357
2358 default:
2359 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2360 spec->type = FORMAT_TYPE_INVALID;
2361 return fmt - start;
2362 }
2363
2364 if (qualifier == 'L')
2365 spec->type = FORMAT_TYPE_LONG_LONG;
2366 else if (qualifier == 'l') {
2367 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2368 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2369 } else if (qualifier == 'z') {
2370 spec->type = FORMAT_TYPE_SIZE_T;
2371 } else if (qualifier == 't') {
2372 spec->type = FORMAT_TYPE_PTRDIFF;
2373 } else if (qualifier == 'H') {
2374 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2375 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2376 } else if (qualifier == 'h') {
2377 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2378 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2379 } else {
2380 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2381 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2382 }
2383
2384 return ++fmt - start;
2385 }
2386
2387 static void
2388 set_field_width(struct printf_spec *spec, int width)
2389 {
2390 spec->field_width = width;
2391 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2392 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2393 }
2394 }
2395
2396 static void
2397 set_precision(struct printf_spec *spec, int prec)
2398 {
2399 spec->precision = prec;
2400 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2401 spec->precision = clamp(prec, 0, PRECISION_MAX);
2402 }
2403 }
2404
2405 /**
2406 * vsnprintf - 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 * @args: Arguments for the format string
2411 *
2412 * This function generally follows C99 vsnprintf, but has some
2413 * extensions and a few limitations:
2414 *
2415 * - ``%n`` is unsupported
2416 * - ``%p*`` is handled by pointer()
2417 *
2418 * See pointer() or Documentation/core-api/printk-formats.rst for more
2419 * extensive description.
2420 *
2421 * **Please update the documentation in both places when making changes**
2422 *
2423 * The return value is the number of characters which would
2424 * be generated for the given input, excluding the trailing
2425 * '\0', as per ISO C99. If you want to have the exact
2426 * number of characters written into @buf as return value
2427 * (not including the trailing '\0'), use vscnprintf(). If the
2428 * return is greater than or equal to @size, the resulting
2429 * string is truncated.
2430 *
2431 * If you're not already dealing with a va_list consider using snprintf().
2432 */
2433 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2434 {
2435 unsigned long long num;
2436 char *str, *end;
2437 struct printf_spec spec = {0};
2438
2439 /* Reject out-of-range values early. Large positive sizes are
2440 used for unknown buffer sizes. */
2441 if (WARN_ON_ONCE(size > INT_MAX))
2442 return 0;
2443
2444 str = buf;
2445 end = buf + size;
2446
2447 /* Make sure end is always >= buf */
2448 if (end < buf) {
2449 end = ((void *)-1);
2450 size = end - buf;
2451 }
2452
2453 while (*fmt) {
2454 const char *old_fmt = fmt;
2455 int read = format_decode(fmt, &spec);
2456
2457 fmt += read;
2458
2459 switch (spec.type) {
2460 case FORMAT_TYPE_NONE: {
2461 int copy = read;
2462 if (str < end) {
2463 if (copy > end - str)
2464 copy = end - str;
2465 memcpy(str, old_fmt, copy);
2466 }
2467 str += read;
2468 break;
2469 }
2470
2471 case FORMAT_TYPE_WIDTH:
2472 set_field_width(&spec, va_arg(args, int));
2473 break;
2474
2475 case FORMAT_TYPE_PRECISION:
2476 set_precision(&spec, va_arg(args, int));
2477 break;
2478
2479 case FORMAT_TYPE_CHAR: {
2480 char c;
2481
2482 if (!(spec.flags & LEFT)) {
2483 while (--spec.field_width > 0) {
2484 if (str < end)
2485 *str = ' ';
2486 ++str;
2487
2488 }
2489 }
2490 c = (unsigned char) va_arg(args, int);
2491 if (str < end)
2492 *str = c;
2493 ++str;
2494 while (--spec.field_width > 0) {
2495 if (str < end)
2496 *str = ' ';
2497 ++str;
2498 }
2499 break;
2500 }
2501
2502 case FORMAT_TYPE_STR:
2503 str = string(str, end, va_arg(args, char *), spec);
2504 break;
2505
2506 case FORMAT_TYPE_PTR:
2507 str = pointer(fmt, str, end, va_arg(args, void *),
2508 spec);
2509 while (isalnum(*fmt))
2510 fmt++;
2511 break;
2512
2513 case FORMAT_TYPE_PERCENT_CHAR:
2514 if (str < end)
2515 *str = '%';
2516 ++str;
2517 break;
2518
2519 case FORMAT_TYPE_INVALID:
2520 /*
2521 * Presumably the arguments passed gcc's type
2522 * checking, but there is no safe or sane way
2523 * for us to continue parsing the format and
2524 * fetching from the va_list; the remaining
2525 * specifiers and arguments would be out of
2526 * sync.
2527 */
2528 goto out;
2529
2530 default:
2531 switch (spec.type) {
2532 case FORMAT_TYPE_LONG_LONG:
2533 num = va_arg(args, long long);
2534 break;
2535 case FORMAT_TYPE_ULONG:
2536 num = va_arg(args, unsigned long);
2537 break;
2538 case FORMAT_TYPE_LONG:
2539 num = va_arg(args, long);
2540 break;
2541 case FORMAT_TYPE_SIZE_T:
2542 if (spec.flags & SIGN)
2543 num = va_arg(args, ssize_t);
2544 else
2545 num = va_arg(args, size_t);
2546 break;
2547 case FORMAT_TYPE_PTRDIFF:
2548 num = va_arg(args, ptrdiff_t);
2549 break;
2550 case FORMAT_TYPE_UBYTE:
2551 num = (unsigned char) va_arg(args, int);
2552 break;
2553 case FORMAT_TYPE_BYTE:
2554 num = (signed char) va_arg(args, int);
2555 break;
2556 case FORMAT_TYPE_USHORT:
2557 num = (unsigned short) va_arg(args, int);
2558 break;
2559 case FORMAT_TYPE_SHORT:
2560 num = (short) va_arg(args, int);
2561 break;
2562 case FORMAT_TYPE_INT:
2563 num = (int) va_arg(args, int);
2564 break;
2565 default:
2566 num = va_arg(args, unsigned int);
2567 }
2568
2569 str = number(str, end, num, spec);
2570 }
2571 }
2572
2573 out:
2574 if (size > 0) {
2575 if (str < end)
2576 *str = '\0';
2577 else
2578 end[-1] = '\0';
2579 }
2580
2581 /* the trailing null byte doesn't count towards the total */
2582 return str-buf;
2583
2584 }
2585 EXPORT_SYMBOL(vsnprintf);
2586
2587 /**
2588 * vscnprintf - Format a string and place it in a buffer
2589 * @buf: The buffer to place the result into
2590 * @size: The size of the buffer, including the trailing null space
2591 * @fmt: The format string to use
2592 * @args: Arguments for the format string
2593 *
2594 * The return value is the number of characters which have been written into
2595 * the @buf not including the trailing '\0'. If @size is == 0 the function
2596 * returns 0.
2597 *
2598 * If you're not already dealing with a va_list consider using scnprintf().
2599 *
2600 * See the vsnprintf() documentation for format string extensions over C99.
2601 */
2602 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2603 {
2604 int i;
2605
2606 i = vsnprintf(buf, size, fmt, args);
2607
2608 if (likely(i < size))
2609 return i;
2610 if (size != 0)
2611 return size - 1;
2612 return 0;
2613 }
2614 EXPORT_SYMBOL(vscnprintf);
2615
2616 /**
2617 * snprintf - Format a string and place it in a buffer
2618 * @buf: The buffer to place the result into
2619 * @size: The size of the buffer, including the trailing null space
2620 * @fmt: The format string to use
2621 * @...: Arguments for the format string
2622 *
2623 * The return value is the number of characters which would be
2624 * generated for the given input, excluding the trailing null,
2625 * as per ISO C99. If the return is greater than or equal to
2626 * @size, the resulting string is truncated.
2627 *
2628 * See the vsnprintf() documentation for format string extensions over C99.
2629 */
2630 int snprintf(char *buf, size_t size, const char *fmt, ...)
2631 {
2632 va_list args;
2633 int i;
2634
2635 va_start(args, fmt);
2636 i = vsnprintf(buf, size, fmt, args);
2637 va_end(args);
2638
2639 return i;
2640 }
2641 EXPORT_SYMBOL(snprintf);
2642
2643 /**
2644 * scnprintf - Format a string and place it in a buffer
2645 * @buf: The buffer to place the result into
2646 * @size: The size of the buffer, including the trailing null space
2647 * @fmt: The format string to use
2648 * @...: Arguments for the format string
2649 *
2650 * The return value is the number of characters written into @buf not including
2651 * the trailing '\0'. If @size is == 0 the function returns 0.
2652 */
2653
2654 int scnprintf(char *buf, size_t size, const char *fmt, ...)
2655 {
2656 va_list args;
2657 int i;
2658
2659 va_start(args, fmt);
2660 i = vscnprintf(buf, size, fmt, args);
2661 va_end(args);
2662
2663 return i;
2664 }
2665 EXPORT_SYMBOL(scnprintf);
2666
2667 /**
2668 * vsprintf - Format a string and place it in a buffer
2669 * @buf: The buffer to place the result into
2670 * @fmt: The format string to use
2671 * @args: Arguments for the format string
2672 *
2673 * The function returns the number of characters written
2674 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2675 * buffer overflows.
2676 *
2677 * If you're not already dealing with a va_list consider using sprintf().
2678 *
2679 * See the vsnprintf() documentation for format string extensions over C99.
2680 */
2681 int vsprintf(char *buf, const char *fmt, va_list args)
2682 {
2683 return vsnprintf(buf, INT_MAX, fmt, args);
2684 }
2685 EXPORT_SYMBOL(vsprintf);
2686
2687 /**
2688 * sprintf - Format a string and place it in a buffer
2689 * @buf: The buffer to place the result into
2690 * @fmt: The format string to use
2691 * @...: Arguments for the format string
2692 *
2693 * The function returns the number of characters written
2694 * into @buf. Use snprintf() or scnprintf() in order to avoid
2695 * buffer overflows.
2696 *
2697 * See the vsnprintf() documentation for format string extensions over C99.
2698 */
2699 int sprintf(char *buf, const char *fmt, ...)
2700 {
2701 va_list args;
2702 int i;
2703
2704 va_start(args, fmt);
2705 i = vsnprintf(buf, INT_MAX, fmt, args);
2706 va_end(args);
2707
2708 return i;
2709 }
2710 EXPORT_SYMBOL(sprintf);
2711
2712 #ifdef CONFIG_BINARY_PRINTF
2713 /*
2714 * bprintf service:
2715 * vbin_printf() - VA arguments to binary data
2716 * bstr_printf() - Binary data to text string
2717 */
2718
2719 /**
2720 * vbin_printf - Parse a format string and place args' binary value in a buffer
2721 * @bin_buf: The buffer to place args' binary value
2722 * @size: The size of the buffer(by words(32bits), not characters)
2723 * @fmt: The format string to use
2724 * @args: Arguments for the format string
2725 *
2726 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2727 * is skipped.
2728 *
2729 * The return value is the number of words(32bits) which would be generated for
2730 * the given input.
2731 *
2732 * NOTE:
2733 * If the return value is greater than @size, the resulting bin_buf is NOT
2734 * valid for bstr_printf().
2735 */
2736 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2737 {
2738 struct printf_spec spec = {0};
2739 char *str, *end;
2740 int width;
2741
2742 str = (char *)bin_buf;
2743 end = (char *)(bin_buf + size);
2744
2745 #define save_arg(type) \
2746 ({ \
2747 unsigned long long value; \
2748 if (sizeof(type) == 8) { \
2749 unsigned long long val8; \
2750 str = PTR_ALIGN(str, sizeof(u32)); \
2751 val8 = va_arg(args, unsigned long long); \
2752 if (str + sizeof(type) <= end) { \
2753 *(u32 *)str = *(u32 *)&val8; \
2754 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \
2755 } \
2756 value = val8; \
2757 } else { \
2758 unsigned int val4; \
2759 str = PTR_ALIGN(str, sizeof(type)); \
2760 val4 = va_arg(args, int); \
2761 if (str + sizeof(type) <= end) \
2762 *(typeof(type) *)str = (type)(long)val4; \
2763 value = (unsigned long long)val4; \
2764 } \
2765 str += sizeof(type); \
2766 value; \
2767 })
2768
2769 while (*fmt) {
2770 int read = format_decode(fmt, &spec);
2771
2772 fmt += read;
2773
2774 switch (spec.type) {
2775 case FORMAT_TYPE_NONE:
2776 case FORMAT_TYPE_PERCENT_CHAR:
2777 break;
2778 case FORMAT_TYPE_INVALID:
2779 goto out;
2780
2781 case FORMAT_TYPE_WIDTH:
2782 case FORMAT_TYPE_PRECISION:
2783 width = (int)save_arg(int);
2784 /* Pointers may require the width */
2785 if (*fmt == 'p')
2786 set_field_width(&spec, width);
2787 break;
2788
2789 case FORMAT_TYPE_CHAR:
2790 save_arg(char);
2791 break;
2792
2793 case FORMAT_TYPE_STR: {
2794 const char *save_str = va_arg(args, char *);
2795 const char *err_msg;
2796 size_t len;
2797
2798 err_msg = check_pointer_msg(save_str);
2799 if (err_msg)
2800 save_str = err_msg;
2801
2802 len = strlen(save_str) + 1;
2803 if (str + len < end)
2804 memcpy(str, save_str, len);
2805 str += len;
2806 break;
2807 }
2808
2809 case FORMAT_TYPE_PTR:
2810 /* Dereferenced pointers must be done now */
2811 switch (*fmt) {
2812 /* Dereference of functions is still OK */
2813 case 'S':
2814 case 's':
2815 case 'F':
2816 case 'f':
2817 case 'x':
2818 case 'K':
2819 save_arg(void *);
2820 break;
2821 default:
2822 if (!isalnum(*fmt)) {
2823 save_arg(void *);
2824 break;
2825 }
2826 str = pointer(fmt, str, end, va_arg(args, void *),
2827 spec);
2828 if (str + 1 < end)
2829 *str++ = '\0';
2830 else
2831 end[-1] = '\0'; /* Must be nul terminated */
2832 }
2833 /* skip all alphanumeric pointer suffixes */
2834 while (isalnum(*fmt))
2835 fmt++;
2836 break;
2837
2838 default:
2839 switch (spec.type) {
2840
2841 case FORMAT_TYPE_LONG_LONG:
2842 save_arg(long long);
2843 break;
2844 case FORMAT_TYPE_ULONG:
2845 case FORMAT_TYPE_LONG:
2846 save_arg(unsigned long);
2847 break;
2848 case FORMAT_TYPE_SIZE_T:
2849 save_arg(size_t);
2850 break;
2851 case FORMAT_TYPE_PTRDIFF:
2852 save_arg(ptrdiff_t);
2853 break;
2854 case FORMAT_TYPE_UBYTE:
2855 case FORMAT_TYPE_BYTE:
2856 save_arg(char);
2857 break;
2858 case FORMAT_TYPE_USHORT:
2859 case FORMAT_TYPE_SHORT:
2860 save_arg(short);
2861 break;
2862 default:
2863 save_arg(int);
2864 }
2865 }
2866 }
2867
2868 out:
2869 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2870 #undef save_arg
2871 }
2872 EXPORT_SYMBOL_GPL(vbin_printf);
2873
2874 /**
2875 * bstr_printf - Format a string from binary arguments and place it in a buffer
2876 * @buf: The buffer to place the result into
2877 * @size: The size of the buffer, including the trailing null space
2878 * @fmt: The format string to use
2879 * @bin_buf: Binary arguments for the format string
2880 *
2881 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2882 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2883 * a binary buffer that generated by vbin_printf.
2884 *
2885 * The format follows C99 vsnprintf, but has some extensions:
2886 * see vsnprintf comment for details.
2887 *
2888 * The return value is the number of characters which would
2889 * be generated for the given input, excluding the trailing
2890 * '\0', as per ISO C99. If you want to have the exact
2891 * number of characters written into @buf as return value
2892 * (not including the trailing '\0'), use vscnprintf(). If the
2893 * return is greater than or equal to @size, the resulting
2894 * string is truncated.
2895 */
2896 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2897 {
2898 struct printf_spec spec = {0};
2899 char *str, *end;
2900 const char *args = (const char *)bin_buf;
2901
2902 if (WARN_ON_ONCE(size > INT_MAX))
2903 return 0;
2904
2905 str = buf;
2906 end = buf + size;
2907
2908 #define get_arg(type) \
2909 ({ \
2910 typeof(type) value; \
2911 if (sizeof(type) == 8) { \
2912 args = PTR_ALIGN(args, sizeof(u32)); \
2913 *(u32 *)&value = *(u32 *)args; \
2914 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2915 } else { \
2916 args = PTR_ALIGN(args, sizeof(type)); \
2917 value = *(typeof(type) *)args; \
2918 } \
2919 args += sizeof(type); \
2920 value; \
2921 })
2922
2923 /* Make sure end is always >= buf */
2924 if (end < buf) {
2925 end = ((void *)-1);
2926 size = end - buf;
2927 }
2928
2929 while (*fmt) {
2930 const char *old_fmt = fmt;
2931 int read = format_decode(fmt, &spec);
2932
2933 fmt += read;
2934
2935 switch (spec.type) {
2936 case FORMAT_TYPE_NONE: {
2937 int copy = read;
2938 if (str < end) {
2939 if (copy > end - str)
2940 copy = end - str;
2941 memcpy(str, old_fmt, copy);
2942 }
2943 str += read;
2944 break;
2945 }
2946
2947 case FORMAT_TYPE_WIDTH:
2948 set_field_width(&spec, get_arg(int));
2949 break;
2950
2951 case FORMAT_TYPE_PRECISION:
2952 set_precision(&spec, get_arg(int));
2953 break;
2954
2955 case FORMAT_TYPE_CHAR: {
2956 char c;
2957
2958 if (!(spec.flags & LEFT)) {
2959 while (--spec.field_width > 0) {
2960 if (str < end)
2961 *str = ' ';
2962 ++str;
2963 }
2964 }
2965 c = (unsigned char) get_arg(char);
2966 if (str < end)
2967 *str = c;
2968 ++str;
2969 while (--spec.field_width > 0) {
2970 if (str < end)
2971 *str = ' ';
2972 ++str;
2973 }
2974 break;
2975 }
2976
2977 case FORMAT_TYPE_STR: {
2978 const char *str_arg = args;
2979 args += strlen(str_arg) + 1;
2980 str = string(str, end, (char *)str_arg, spec);
2981 break;
2982 }
2983
2984 case FORMAT_TYPE_PTR: {
2985 bool process = false;
2986 int copy, len;
2987 /* Non function dereferences were already done */
2988 switch (*fmt) {
2989 case 'S':
2990 case 's':
2991 case 'F':
2992 case 'f':
2993 case 'x':
2994 case 'K':
2995 process = true;
2996 break;
2997 default:
2998 if (!isalnum(*fmt)) {
2999 process = true;
3000 break;
3001 }
3002 /* Pointer dereference was already processed */
3003 if (str < end) {
3004 len = copy = strlen(args);
3005 if (copy > end - str)
3006 copy = end - str;
3007 memcpy(str, args, copy);
3008 str += len;
3009 args += len + 1;
3010 }
3011 }
3012 if (process)
3013 str = pointer(fmt, str, end, get_arg(void *), spec);
3014
3015 while (isalnum(*fmt))
3016 fmt++;
3017 break;
3018 }
3019
3020 case FORMAT_TYPE_PERCENT_CHAR:
3021 if (str < end)
3022 *str = '%';
3023 ++str;
3024 break;
3025
3026 case FORMAT_TYPE_INVALID:
3027 goto out;
3028
3029 default: {
3030 unsigned long long num;
3031
3032 switch (spec.type) {
3033
3034 case FORMAT_TYPE_LONG_LONG:
3035 num = get_arg(long long);
3036 break;
3037 case FORMAT_TYPE_ULONG:
3038 case FORMAT_TYPE_LONG:
3039 num = get_arg(unsigned long);
3040 break;
3041 case FORMAT_TYPE_SIZE_T:
3042 num = get_arg(size_t);
3043 break;
3044 case FORMAT_TYPE_PTRDIFF:
3045 num = get_arg(ptrdiff_t);
3046 break;
3047 case FORMAT_TYPE_UBYTE:
3048 num = get_arg(unsigned char);
3049 break;
3050 case FORMAT_TYPE_BYTE:
3051 num = get_arg(signed char);
3052 break;
3053 case FORMAT_TYPE_USHORT:
3054 num = get_arg(unsigned short);
3055 break;
3056 case FORMAT_TYPE_SHORT:
3057 num = get_arg(short);
3058 break;
3059 case FORMAT_TYPE_UINT:
3060 num = get_arg(unsigned int);
3061 break;
3062 default:
3063 num = get_arg(int);
3064 }
3065
3066 str = number(str, end, num, spec);
3067 } /* default: */
3068 } /* switch(spec.type) */
3069 } /* while(*fmt) */
3070
3071 out:
3072 if (size > 0) {
3073 if (str < end)
3074 *str = '\0';
3075 else
3076 end[-1] = '\0';
3077 }
3078
3079 #undef get_arg
3080
3081 /* the trailing null byte doesn't count towards the total */
3082 return str - buf;
3083 }
3084 EXPORT_SYMBOL_GPL(bstr_printf);
3085
3086 /**
3087 * bprintf - Parse a format string and place args' binary value in a buffer
3088 * @bin_buf: The buffer to place args' binary value
3089 * @size: The size of the buffer(by words(32bits), not characters)
3090 * @fmt: The format string to use
3091 * @...: Arguments for the format string
3092 *
3093 * The function returns the number of words(u32) written
3094 * into @bin_buf.
3095 */
3096 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
3097 {
3098 va_list args;
3099 int ret;
3100
3101 va_start(args, fmt);
3102 ret = vbin_printf(bin_buf, size, fmt, args);
3103 va_end(args);
3104
3105 return ret;
3106 }
3107 EXPORT_SYMBOL_GPL(bprintf);
3108
3109 #endif /* CONFIG_BINARY_PRINTF */
3110
3111 /**
3112 * vsscanf - Unformat a buffer into a list of arguments
3113 * @buf: input buffer
3114 * @fmt: format of buffer
3115 * @args: arguments
3116 */
3117 int vsscanf(const char *buf, const char *fmt, va_list args)
3118 {
3119 const char *str = buf;
3120 char *next;
3121 char digit;
3122 int num = 0;
3123 u8 qualifier;
3124 unsigned int base;
3125 union {
3126 long long s;
3127 unsigned long long u;
3128 } val;
3129 s16 field_width;
3130 bool is_sign;
3131
3132 while (*fmt) {
3133 /* skip any white space in format */
3134 /* white space in format matchs any amount of
3135 * white space, including none, in the input.
3136 */
3137 if (isspace(*fmt)) {
3138 fmt = skip_spaces(++fmt);
3139 str = skip_spaces(str);
3140 }
3141
3142 /* anything that is not a conversion must match exactly */
3143 if (*fmt != '%' && *fmt) {
3144 if (*fmt++ != *str++)
3145 break;
3146 continue;
3147 }
3148
3149 if (!*fmt)
3150 break;
3151 ++fmt;
3152
3153 /* skip this conversion.
3154 * advance both strings to next white space
3155 */
3156 if (*fmt == '*') {
3157 if (!*str)
3158 break;
3159 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
3160 /* '%*[' not yet supported, invalid format */
3161 if (*fmt == '[')
3162 return num;
3163 fmt++;
3164 }
3165 while (!isspace(*str) && *str)
3166 str++;
3167 continue;
3168 }
3169
3170 /* get field width */
3171 field_width = -1;
3172 if (isdigit(*fmt)) {
3173 field_width = skip_atoi(&fmt);
3174 if (field_width <= 0)
3175 break;
3176 }
3177
3178 /* get conversion qualifier */
3179 qualifier = -1;
3180 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
3181 *fmt == 'z') {
3182 qualifier = *fmt++;
3183 if (unlikely(qualifier == *fmt)) {
3184 if (qualifier == 'h') {
3185 qualifier = 'H';
3186 fmt++;
3187 } else if (qualifier == 'l') {
3188 qualifier = 'L';
3189 fmt++;
3190 }
3191 }
3192 }
3193
3194 if (!*fmt)
3195 break;
3196
3197 if (*fmt == 'n') {
3198 /* return number of characters read so far */
3199 *va_arg(args, int *) = str - buf;
3200 ++fmt;
3201 continue;
3202 }
3203
3204 if (!*str)
3205 break;
3206
3207 base = 10;
3208 is_sign = false;
3209
3210 switch (*fmt++) {
3211 case 'c':
3212 {
3213 char *s = (char *)va_arg(args, char*);
3214 if (field_width == -1)
3215 field_width = 1;
3216 do {
3217 *s++ = *str++;
3218 } while (--field_width > 0 && *str);
3219 num++;
3220 }
3221 continue;
3222 case 's':
3223 {
3224 char *s = (char *)va_arg(args, char *);
3225 if (field_width == -1)
3226 field_width = SHRT_MAX;
3227 /* first, skip leading white space in buffer */
3228 str = skip_spaces(str);
3229
3230 /* now copy until next white space */
3231 while (*str && !isspace(*str) && field_width--)
3232 *s++ = *str++;
3233 *s = '\0';
3234 num++;
3235 }
3236 continue;
3237 /*
3238 * Warning: This implementation of the '[' conversion specifier
3239 * deviates from its glibc counterpart in the following ways:
3240 * (1) It does NOT support ranges i.e. '-' is NOT a special
3241 * character
3242 * (2) It cannot match the closing bracket ']' itself
3243 * (3) A field width is required
3244 * (4) '%*[' (discard matching input) is currently not supported
3245 *
3246 * Example usage:
3247 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3248 * buf1, buf2, buf3);
3249 * if (ret < 3)
3250 * // etc..
3251 */
3252 case '[':
3253 {
3254 char *s = (char *)va_arg(args, char *);
3255 DECLARE_BITMAP(set, 256) = {0};
3256 unsigned int len = 0;
3257 bool negate = (*fmt == '^');
3258
3259 /* field width is required */
3260 if (field_width == -1)
3261 return num;
3262
3263 if (negate)
3264 ++fmt;
3265
3266 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3267 set_bit((u8)*fmt, set);
3268
3269 /* no ']' or no character set found */
3270 if (!*fmt || !len)
3271 return num;
3272 ++fmt;
3273
3274 if (negate) {
3275 bitmap_complement(set, set, 256);
3276 /* exclude null '\0' byte */
3277 clear_bit(0, set);
3278 }
3279
3280 /* match must be non-empty */
3281 if (!test_bit((u8)*str, set))
3282 return num;
3283
3284 while (test_bit((u8)*str, set) && field_width--)
3285 *s++ = *str++;
3286 *s = '\0';
3287 ++num;
3288 }
3289 continue;
3290 case 'o':
3291 base = 8;
3292 break;
3293 case 'x':
3294 case 'X':
3295 base = 16;
3296 break;
3297 case 'i':
3298 base = 0;
3299 /* fall through */
3300 case 'd':
3301 is_sign = true;
3302 /* fall through */
3303 case 'u':
3304 break;
3305 case '%':
3306 /* looking for '%' in str */
3307 if (*str++ != '%')
3308 return num;
3309 continue;
3310 default:
3311 /* invalid format; stop here */
3312 return num;
3313 }
3314
3315 /* have some sort of integer conversion.
3316 * first, skip white space in buffer.
3317 */
3318 str = skip_spaces(str);
3319
3320 digit = *str;
3321 if (is_sign && digit == '-')
3322 digit = *(str + 1);
3323
3324 if (!digit
3325 || (base == 16 && !isxdigit(digit))
3326 || (base == 10 && !isdigit(digit))
3327 || (base == 8 && (!isdigit(digit) || digit > '7'))
3328 || (base == 0 && !isdigit(digit)))
3329 break;
3330
3331 if (is_sign)
3332 val.s = qualifier != 'L' ?
3333 simple_strtol(str, &next, base) :
3334 simple_strtoll(str, &next, base);
3335 else
3336 val.u = qualifier != 'L' ?
3337 simple_strtoul(str, &next, base) :
3338 simple_strtoull(str, &next, base);
3339
3340 if (field_width > 0 && next - str > field_width) {
3341 if (base == 0)
3342 _parse_integer_fixup_radix(str, &base);
3343 while (next - str > field_width) {
3344 if (is_sign)
3345 val.s = div_s64(val.s, base);
3346 else
3347 val.u = div_u64(val.u, base);
3348 --next;
3349 }
3350 }
3351
3352 switch (qualifier) {
3353 case 'H': /* that's 'hh' in format */
3354 if (is_sign)
3355 *va_arg(args, signed char *) = val.s;
3356 else
3357 *va_arg(args, unsigned char *) = val.u;
3358 break;
3359 case 'h':
3360 if (is_sign)
3361 *va_arg(args, short *) = val.s;
3362 else
3363 *va_arg(args, unsigned short *) = val.u;
3364 break;
3365 case 'l':
3366 if (is_sign)
3367 *va_arg(args, long *) = val.s;
3368 else
3369 *va_arg(args, unsigned long *) = val.u;
3370 break;
3371 case 'L':
3372 if (is_sign)
3373 *va_arg(args, long long *) = val.s;
3374 else
3375 *va_arg(args, unsigned long long *) = val.u;
3376 break;
3377 case 'z':
3378 *va_arg(args, size_t *) = val.u;
3379 break;
3380 default:
3381 if (is_sign)
3382 *va_arg(args, int *) = val.s;
3383 else
3384 *va_arg(args, unsigned int *) = val.u;
3385 break;
3386 }
3387 num++;
3388
3389 if (!next)
3390 break;
3391 str = next;
3392 }
3393
3394 return num;
3395 }
3396 EXPORT_SYMBOL(vsscanf);
3397
3398 /**
3399 * sscanf - Unformat a buffer into a list of arguments
3400 * @buf: input buffer
3401 * @fmt: formatting of buffer
3402 * @...: resulting arguments
3403 */
3404 int sscanf(const char *buf, const char *fmt, ...)
3405 {
3406 va_list args;
3407 int i;
3408
3409 va_start(args, fmt);
3410 i = vsscanf(buf, fmt, args);
3411 va_end(args);
3412
3413 return i;
3414 }
3415 EXPORT_SYMBOL(sscanf);
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