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vsprintf: don't obfuscate NULL and error pointers
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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59 * This function is obsolete.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84 * This function is obsolete.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 int 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 /*
750 * Print the real pointer value for NULL and error pointers,
751 * as they are not actual addresses.
752 */
753 if (IS_ERR_OR_NULL(ptr))
754 return pointer_string(buf, end, ptr, spec);
755
756 /* When debugging early boot use non-cryptographically secure hash. */
757 if (unlikely(debug_boot_weak_hash)) {
758 hashval = hash_long((unsigned long)ptr, 32);
759 return pointer_string(buf, end, (const void *)hashval, spec);
760 }
761
762 if (static_branch_unlikely(&not_filled_random_ptr_key)) {
763 spec.field_width = 2 * sizeof(ptr);
764 /* string length must be less than default_width */
765 return error_string(buf, end, str, spec);
766 }
767
768 #ifdef CONFIG_64BIT
769 hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key);
770 /*
771 * Mask off the first 32 bits, this makes explicit that we have
772 * modified the address (and 32 bits is plenty for a unique ID).
773 */
774 hashval = hashval & 0xffffffff;
775 #else
776 hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key);
777 #endif
778 return pointer_string(buf, end, (const void *)hashval, spec);
779 }
780
781 int kptr_restrict __read_mostly;
782
783 static noinline_for_stack
784 char *restricted_pointer(char *buf, char *end, const void *ptr,
785 struct printf_spec spec)
786 {
787 switch (kptr_restrict) {
788 case 0:
789 /* Handle as %p, hash and do _not_ leak addresses. */
790 return ptr_to_id(buf, end, ptr, spec);
791 case 1: {
792 const struct cred *cred;
793
794 /*
795 * kptr_restrict==1 cannot be used in IRQ context
796 * because its test for CAP_SYSLOG would be meaningless.
797 */
798 if (in_irq() || in_serving_softirq() || in_nmi()) {
799 if (spec.field_width == -1)
800 spec.field_width = 2 * sizeof(ptr);
801 return error_string(buf, end, "pK-error", spec);
802 }
803
804 /*
805 * Only print the real pointer value if the current
806 * process has CAP_SYSLOG and is running with the
807 * same credentials it started with. This is because
808 * access to files is checked at open() time, but %pK
809 * checks permission at read() time. We don't want to
810 * leak pointer values if a binary opens a file using
811 * %pK and then elevates privileges before reading it.
812 */
813 cred = current_cred();
814 if (!has_capability_noaudit(current, CAP_SYSLOG) ||
815 !uid_eq(cred->euid, cred->uid) ||
816 !gid_eq(cred->egid, cred->gid))
817 ptr = NULL;
818 break;
819 }
820 case 2:
821 default:
822 /* Always print 0's for %pK */
823 ptr = NULL;
824 break;
825 }
826
827 return pointer_string(buf, end, ptr, spec);
828 }
829
830 static noinline_for_stack
831 char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec,
832 const char *fmt)
833 {
834 const char *array[4], *s;
835 const struct dentry *p;
836 int depth;
837 int i, n;
838
839 switch (fmt[1]) {
840 case '2': case '3': case '4':
841 depth = fmt[1] - '0';
842 break;
843 default:
844 depth = 1;
845 }
846
847 rcu_read_lock();
848 for (i = 0; i < depth; i++, d = p) {
849 if (check_pointer(&buf, end, d, spec)) {
850 rcu_read_unlock();
851 return buf;
852 }
853
854 p = READ_ONCE(d->d_parent);
855 array[i] = READ_ONCE(d->d_name.name);
856 if (p == d) {
857 if (i)
858 array[i] = "";
859 i++;
860 break;
861 }
862 }
863 s = array[--i];
864 for (n = 0; n != spec.precision; n++, buf++) {
865 char c = *s++;
866 if (!c) {
867 if (!i)
868 break;
869 c = '/';
870 s = array[--i];
871 }
872 if (buf < end)
873 *buf = c;
874 }
875 rcu_read_unlock();
876 return widen_string(buf, n, end, spec);
877 }
878
879 static noinline_for_stack
880 char *file_dentry_name(char *buf, char *end, const struct file *f,
881 struct printf_spec spec, const char *fmt)
882 {
883 if (check_pointer(&buf, end, f, spec))
884 return buf;
885
886 return dentry_name(buf, end, f->f_path.dentry, spec, fmt);
887 }
888 #ifdef CONFIG_BLOCK
889 static noinline_for_stack
890 char *bdev_name(char *buf, char *end, struct block_device *bdev,
891 struct printf_spec spec, const char *fmt)
892 {
893 struct gendisk *hd;
894
895 if (check_pointer(&buf, end, bdev, spec))
896 return buf;
897
898 hd = bdev->bd_disk;
899 buf = string(buf, end, hd->disk_name, spec);
900 if (bdev->bd_part->partno) {
901 if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) {
902 if (buf < end)
903 *buf = 'p';
904 buf++;
905 }
906 buf = number(buf, end, bdev->bd_part->partno, spec);
907 }
908 return buf;
909 }
910 #endif
911
912 static noinline_for_stack
913 char *symbol_string(char *buf, char *end, void *ptr,
914 struct printf_spec spec, const char *fmt)
915 {
916 unsigned long value;
917 #ifdef CONFIG_KALLSYMS
918 char sym[KSYM_SYMBOL_LEN];
919 #endif
920
921 if (fmt[1] == 'R')
922 ptr = __builtin_extract_return_addr(ptr);
923 value = (unsigned long)ptr;
924
925 #ifdef CONFIG_KALLSYMS
926 if (*fmt == 'B')
927 sprint_backtrace(sym, value);
928 else if (*fmt != 'f' && *fmt != 's')
929 sprint_symbol(sym, value);
930 else
931 sprint_symbol_no_offset(sym, value);
932
933 return string_nocheck(buf, end, sym, spec);
934 #else
935 return special_hex_number(buf, end, value, sizeof(void *));
936 #endif
937 }
938
939 static const struct printf_spec default_str_spec = {
940 .field_width = -1,
941 .precision = -1,
942 };
943
944 static const struct printf_spec default_flag_spec = {
945 .base = 16,
946 .precision = -1,
947 .flags = SPECIAL | SMALL,
948 };
949
950 static const struct printf_spec default_dec_spec = {
951 .base = 10,
952 .precision = -1,
953 };
954
955 static const struct printf_spec default_dec02_spec = {
956 .base = 10,
957 .field_width = 2,
958 .precision = -1,
959 .flags = ZEROPAD,
960 };
961
962 static const struct printf_spec default_dec04_spec = {
963 .base = 10,
964 .field_width = 4,
965 .precision = -1,
966 .flags = ZEROPAD,
967 };
968
969 static noinline_for_stack
970 char *resource_string(char *buf, char *end, struct resource *res,
971 struct printf_spec spec, const char *fmt)
972 {
973 #ifndef IO_RSRC_PRINTK_SIZE
974 #define IO_RSRC_PRINTK_SIZE 6
975 #endif
976
977 #ifndef MEM_RSRC_PRINTK_SIZE
978 #define MEM_RSRC_PRINTK_SIZE 10
979 #endif
980 static const struct printf_spec io_spec = {
981 .base = 16,
982 .field_width = IO_RSRC_PRINTK_SIZE,
983 .precision = -1,
984 .flags = SPECIAL | SMALL | ZEROPAD,
985 };
986 static const struct printf_spec mem_spec = {
987 .base = 16,
988 .field_width = MEM_RSRC_PRINTK_SIZE,
989 .precision = -1,
990 .flags = SPECIAL | SMALL | ZEROPAD,
991 };
992 static const struct printf_spec bus_spec = {
993 .base = 16,
994 .field_width = 2,
995 .precision = -1,
996 .flags = SMALL | ZEROPAD,
997 };
998 static const struct printf_spec str_spec = {
999 .field_width = -1,
1000 .precision = 10,
1001 .flags = LEFT,
1002 };
1003
1004 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
1005 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
1006 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
1007 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
1008 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
1009 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
1010 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
1011 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
1012
1013 char *p = sym, *pend = sym + sizeof(sym);
1014 int decode = (fmt[0] == 'R') ? 1 : 0;
1015 const struct printf_spec *specp;
1016
1017 if (check_pointer(&buf, end, res, spec))
1018 return buf;
1019
1020 *p++ = '[';
1021 if (res->flags & IORESOURCE_IO) {
1022 p = string_nocheck(p, pend, "io ", str_spec);
1023 specp = &io_spec;
1024 } else if (res->flags & IORESOURCE_MEM) {
1025 p = string_nocheck(p, pend, "mem ", str_spec);
1026 specp = &mem_spec;
1027 } else if (res->flags & IORESOURCE_IRQ) {
1028 p = string_nocheck(p, pend, "irq ", str_spec);
1029 specp = &default_dec_spec;
1030 } else if (res->flags & IORESOURCE_DMA) {
1031 p = string_nocheck(p, pend, "dma ", str_spec);
1032 specp = &default_dec_spec;
1033 } else if (res->flags & IORESOURCE_BUS) {
1034 p = string_nocheck(p, pend, "bus ", str_spec);
1035 specp = &bus_spec;
1036 } else {
1037 p = string_nocheck(p, pend, "??? ", str_spec);
1038 specp = &mem_spec;
1039 decode = 0;
1040 }
1041 if (decode && res->flags & IORESOURCE_UNSET) {
1042 p = string_nocheck(p, pend, "size ", str_spec);
1043 p = number(p, pend, resource_size(res), *specp);
1044 } else {
1045 p = number(p, pend, res->start, *specp);
1046 if (res->start != res->end) {
1047 *p++ = '-';
1048 p = number(p, pend, res->end, *specp);
1049 }
1050 }
1051 if (decode) {
1052 if (res->flags & IORESOURCE_MEM_64)
1053 p = string_nocheck(p, pend, " 64bit", str_spec);
1054 if (res->flags & IORESOURCE_PREFETCH)
1055 p = string_nocheck(p, pend, " pref", str_spec);
1056 if (res->flags & IORESOURCE_WINDOW)
1057 p = string_nocheck(p, pend, " window", str_spec);
1058 if (res->flags & IORESOURCE_DISABLED)
1059 p = string_nocheck(p, pend, " disabled", str_spec);
1060 } else {
1061 p = string_nocheck(p, pend, " flags ", str_spec);
1062 p = number(p, pend, res->flags, default_flag_spec);
1063 }
1064 *p++ = ']';
1065 *p = '\0';
1066
1067 return string_nocheck(buf, end, sym, spec);
1068 }
1069
1070 static noinline_for_stack
1071 char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1072 const char *fmt)
1073 {
1074 int i, len = 1; /* if we pass '%ph[CDN]', field width remains
1075 negative value, fallback to the default */
1076 char separator;
1077
1078 if (spec.field_width == 0)
1079 /* nothing to print */
1080 return buf;
1081
1082 if (check_pointer(&buf, end, addr, spec))
1083 return buf;
1084
1085 switch (fmt[1]) {
1086 case 'C':
1087 separator = ':';
1088 break;
1089 case 'D':
1090 separator = '-';
1091 break;
1092 case 'N':
1093 separator = 0;
1094 break;
1095 default:
1096 separator = ' ';
1097 break;
1098 }
1099
1100 if (spec.field_width > 0)
1101 len = min_t(int, spec.field_width, 64);
1102
1103 for (i = 0; i < len; ++i) {
1104 if (buf < end)
1105 *buf = hex_asc_hi(addr[i]);
1106 ++buf;
1107 if (buf < end)
1108 *buf = hex_asc_lo(addr[i]);
1109 ++buf;
1110
1111 if (separator && i != len - 1) {
1112 if (buf < end)
1113 *buf = separator;
1114 ++buf;
1115 }
1116 }
1117
1118 return buf;
1119 }
1120
1121 static noinline_for_stack
1122 char *bitmap_string(char *buf, char *end, unsigned long *bitmap,
1123 struct printf_spec spec, const char *fmt)
1124 {
1125 const int CHUNKSZ = 32;
1126 int nr_bits = max_t(int, spec.field_width, 0);
1127 int i, chunksz;
1128 bool first = true;
1129
1130 if (check_pointer(&buf, end, bitmap, spec))
1131 return buf;
1132
1133 /* reused to print numbers */
1134 spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 };
1135
1136 chunksz = nr_bits & (CHUNKSZ - 1);
1137 if (chunksz == 0)
1138 chunksz = CHUNKSZ;
1139
1140 i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ;
1141 for (; i >= 0; i -= CHUNKSZ) {
1142 u32 chunkmask, val;
1143 int word, bit;
1144
1145 chunkmask = ((1ULL << chunksz) - 1);
1146 word = i / BITS_PER_LONG;
1147 bit = i % BITS_PER_LONG;
1148 val = (bitmap[word] >> bit) & chunkmask;
1149
1150 if (!first) {
1151 if (buf < end)
1152 *buf = ',';
1153 buf++;
1154 }
1155 first = false;
1156
1157 spec.field_width = DIV_ROUND_UP(chunksz, 4);
1158 buf = number(buf, end, val, spec);
1159
1160 chunksz = CHUNKSZ;
1161 }
1162 return buf;
1163 }
1164
1165 static noinline_for_stack
1166 char *bitmap_list_string(char *buf, char *end, unsigned long *bitmap,
1167 struct printf_spec spec, const char *fmt)
1168 {
1169 int nr_bits = max_t(int, spec.field_width, 0);
1170 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
1171 int cur, rbot, rtop;
1172 bool first = true;
1173
1174 if (check_pointer(&buf, end, bitmap, spec))
1175 return buf;
1176
1177 rbot = cur = find_first_bit(bitmap, nr_bits);
1178 while (cur < nr_bits) {
1179 rtop = cur;
1180 cur = find_next_bit(bitmap, nr_bits, cur + 1);
1181 if (cur < nr_bits && cur <= rtop + 1)
1182 continue;
1183
1184 if (!first) {
1185 if (buf < end)
1186 *buf = ',';
1187 buf++;
1188 }
1189 first = false;
1190
1191 buf = number(buf, end, rbot, default_dec_spec);
1192 if (rbot < rtop) {
1193 if (buf < end)
1194 *buf = '-';
1195 buf++;
1196
1197 buf = number(buf, end, rtop, default_dec_spec);
1198 }
1199
1200 rbot = cur;
1201 }
1202 return buf;
1203 }
1204
1205 static noinline_for_stack
1206 char *mac_address_string(char *buf, char *end, u8 *addr,
1207 struct printf_spec spec, const char *fmt)
1208 {
1209 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
1210 char *p = mac_addr;
1211 int i;
1212 char separator;
1213 bool reversed = false;
1214
1215 if (check_pointer(&buf, end, addr, spec))
1216 return buf;
1217
1218 switch (fmt[1]) {
1219 case 'F':
1220 separator = '-';
1221 break;
1222
1223 case 'R':
1224 reversed = true;
1225 /* fall through */
1226
1227 default:
1228 separator = ':';
1229 break;
1230 }
1231
1232 for (i = 0; i < 6; i++) {
1233 if (reversed)
1234 p = hex_byte_pack(p, addr[5 - i]);
1235 else
1236 p = hex_byte_pack(p, addr[i]);
1237
1238 if (fmt[0] == 'M' && i != 5)
1239 *p++ = separator;
1240 }
1241 *p = '\0';
1242
1243 return string_nocheck(buf, end, mac_addr, spec);
1244 }
1245
1246 static noinline_for_stack
1247 char *ip4_string(char *p, const u8 *addr, const char *fmt)
1248 {
1249 int i;
1250 bool leading_zeros = (fmt[0] == 'i');
1251 int index;
1252 int step;
1253
1254 switch (fmt[2]) {
1255 case 'h':
1256 #ifdef __BIG_ENDIAN
1257 index = 0;
1258 step = 1;
1259 #else
1260 index = 3;
1261 step = -1;
1262 #endif
1263 break;
1264 case 'l':
1265 index = 3;
1266 step = -1;
1267 break;
1268 case 'n':
1269 case 'b':
1270 default:
1271 index = 0;
1272 step = 1;
1273 break;
1274 }
1275 for (i = 0; i < 4; i++) {
1276 char temp[4] __aligned(2); /* hold each IP quad in reverse order */
1277 int digits = put_dec_trunc8(temp, addr[index]) - temp;
1278 if (leading_zeros) {
1279 if (digits < 3)
1280 *p++ = '0';
1281 if (digits < 2)
1282 *p++ = '0';
1283 }
1284 /* reverse the digits in the quad */
1285 while (digits--)
1286 *p++ = temp[digits];
1287 if (i < 3)
1288 *p++ = '.';
1289 index += step;
1290 }
1291 *p = '\0';
1292
1293 return p;
1294 }
1295
1296 static noinline_for_stack
1297 char *ip6_compressed_string(char *p, const char *addr)
1298 {
1299 int i, j, range;
1300 unsigned char zerolength[8];
1301 int longest = 1;
1302 int colonpos = -1;
1303 u16 word;
1304 u8 hi, lo;
1305 bool needcolon = false;
1306 bool useIPv4;
1307 struct in6_addr in6;
1308
1309 memcpy(&in6, addr, sizeof(struct in6_addr));
1310
1311 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
1312
1313 memset(zerolength, 0, sizeof(zerolength));
1314
1315 if (useIPv4)
1316 range = 6;
1317 else
1318 range = 8;
1319
1320 /* find position of longest 0 run */
1321 for (i = 0; i < range; i++) {
1322 for (j = i; j < range; j++) {
1323 if (in6.s6_addr16[j] != 0)
1324 break;
1325 zerolength[i]++;
1326 }
1327 }
1328 for (i = 0; i < range; i++) {
1329 if (zerolength[i] > longest) {
1330 longest = zerolength[i];
1331 colonpos = i;
1332 }
1333 }
1334 if (longest == 1) /* don't compress a single 0 */
1335 colonpos = -1;
1336
1337 /* emit address */
1338 for (i = 0; i < range; i++) {
1339 if (i == colonpos) {
1340 if (needcolon || i == 0)
1341 *p++ = ':';
1342 *p++ = ':';
1343 needcolon = false;
1344 i += longest - 1;
1345 continue;
1346 }
1347 if (needcolon) {
1348 *p++ = ':';
1349 needcolon = false;
1350 }
1351 /* hex u16 without leading 0s */
1352 word = ntohs(in6.s6_addr16[i]);
1353 hi = word >> 8;
1354 lo = word & 0xff;
1355 if (hi) {
1356 if (hi > 0x0f)
1357 p = hex_byte_pack(p, hi);
1358 else
1359 *p++ = hex_asc_lo(hi);
1360 p = hex_byte_pack(p, lo);
1361 }
1362 else if (lo > 0x0f)
1363 p = hex_byte_pack(p, lo);
1364 else
1365 *p++ = hex_asc_lo(lo);
1366 needcolon = true;
1367 }
1368
1369 if (useIPv4) {
1370 if (needcolon)
1371 *p++ = ':';
1372 p = ip4_string(p, &in6.s6_addr[12], "I4");
1373 }
1374 *p = '\0';
1375
1376 return p;
1377 }
1378
1379 static noinline_for_stack
1380 char *ip6_string(char *p, const char *addr, const char *fmt)
1381 {
1382 int i;
1383
1384 for (i = 0; i < 8; i++) {
1385 p = hex_byte_pack(p, *addr++);
1386 p = hex_byte_pack(p, *addr++);
1387 if (fmt[0] == 'I' && i != 7)
1388 *p++ = ':';
1389 }
1390 *p = '\0';
1391
1392 return p;
1393 }
1394
1395 static noinline_for_stack
1396 char *ip6_addr_string(char *buf, char *end, const u8 *addr,
1397 struct printf_spec spec, const char *fmt)
1398 {
1399 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1400
1401 if (fmt[0] == 'I' && fmt[2] == 'c')
1402 ip6_compressed_string(ip6_addr, addr);
1403 else
1404 ip6_string(ip6_addr, addr, fmt);
1405
1406 return string_nocheck(buf, end, ip6_addr, spec);
1407 }
1408
1409 static noinline_for_stack
1410 char *ip4_addr_string(char *buf, char *end, const u8 *addr,
1411 struct printf_spec spec, const char *fmt)
1412 {
1413 char ip4_addr[sizeof("255.255.255.255")];
1414
1415 ip4_string(ip4_addr, addr, fmt);
1416
1417 return string_nocheck(buf, end, ip4_addr, spec);
1418 }
1419
1420 static noinline_for_stack
1421 char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa,
1422 struct printf_spec spec, const char *fmt)
1423 {
1424 bool have_p = false, have_s = false, have_f = false, have_c = false;
1425 char ip6_addr[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1426 sizeof(":12345") + sizeof("/123456789") +
1427 sizeof("%1234567890")];
1428 char *p = ip6_addr, *pend = ip6_addr + sizeof(ip6_addr);
1429 const u8 *addr = (const u8 *) &sa->sin6_addr;
1430 char fmt6[2] = { fmt[0], '6' };
1431 u8 off = 0;
1432
1433 fmt++;
1434 while (isalpha(*++fmt)) {
1435 switch (*fmt) {
1436 case 'p':
1437 have_p = true;
1438 break;
1439 case 'f':
1440 have_f = true;
1441 break;
1442 case 's':
1443 have_s = true;
1444 break;
1445 case 'c':
1446 have_c = true;
1447 break;
1448 }
1449 }
1450
1451 if (have_p || have_s || have_f) {
1452 *p = '[';
1453 off = 1;
1454 }
1455
1456 if (fmt6[0] == 'I' && have_c)
1457 p = ip6_compressed_string(ip6_addr + off, addr);
1458 else
1459 p = ip6_string(ip6_addr + off, addr, fmt6);
1460
1461 if (have_p || have_s || have_f)
1462 *p++ = ']';
1463
1464 if (have_p) {
1465 *p++ = ':';
1466 p = number(p, pend, ntohs(sa->sin6_port), spec);
1467 }
1468 if (have_f) {
1469 *p++ = '/';
1470 p = number(p, pend, ntohl(sa->sin6_flowinfo &
1471 IPV6_FLOWINFO_MASK), spec);
1472 }
1473 if (have_s) {
1474 *p++ = '%';
1475 p = number(p, pend, sa->sin6_scope_id, spec);
1476 }
1477 *p = '\0';
1478
1479 return string_nocheck(buf, end, ip6_addr, spec);
1480 }
1481
1482 static noinline_for_stack
1483 char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa,
1484 struct printf_spec spec, const char *fmt)
1485 {
1486 bool have_p = false;
1487 char *p, ip4_addr[sizeof("255.255.255.255") + sizeof(":12345")];
1488 char *pend = ip4_addr + sizeof(ip4_addr);
1489 const u8 *addr = (const u8 *) &sa->sin_addr.s_addr;
1490 char fmt4[3] = { fmt[0], '4', 0 };
1491
1492 fmt++;
1493 while (isalpha(*++fmt)) {
1494 switch (*fmt) {
1495 case 'p':
1496 have_p = true;
1497 break;
1498 case 'h':
1499 case 'l':
1500 case 'n':
1501 case 'b':
1502 fmt4[2] = *fmt;
1503 break;
1504 }
1505 }
1506
1507 p = ip4_string(ip4_addr, addr, fmt4);
1508 if (have_p) {
1509 *p++ = ':';
1510 p = number(p, pend, ntohs(sa->sin_port), spec);
1511 }
1512 *p = '\0';
1513
1514 return string_nocheck(buf, end, ip4_addr, spec);
1515 }
1516
1517 static noinline_for_stack
1518 char *ip_addr_string(char *buf, char *end, const void *ptr,
1519 struct printf_spec spec, const char *fmt)
1520 {
1521 char *err_fmt_msg;
1522
1523 if (check_pointer(&buf, end, ptr, spec))
1524 return buf;
1525
1526 switch (fmt[1]) {
1527 case '6':
1528 return ip6_addr_string(buf, end, ptr, spec, fmt);
1529 case '4':
1530 return ip4_addr_string(buf, end, ptr, spec, fmt);
1531 case 'S': {
1532 const union {
1533 struct sockaddr raw;
1534 struct sockaddr_in v4;
1535 struct sockaddr_in6 v6;
1536 } *sa = ptr;
1537
1538 switch (sa->raw.sa_family) {
1539 case AF_INET:
1540 return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt);
1541 case AF_INET6:
1542 return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt);
1543 default:
1544 return error_string(buf, end, "(einval)", spec);
1545 }}
1546 }
1547
1548 err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)";
1549 return error_string(buf, end, err_fmt_msg, spec);
1550 }
1551
1552 static noinline_for_stack
1553 char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec,
1554 const char *fmt)
1555 {
1556 bool found = true;
1557 int count = 1;
1558 unsigned int flags = 0;
1559 int len;
1560
1561 if (spec.field_width == 0)
1562 return buf; /* nothing to print */
1563
1564 if (check_pointer(&buf, end, addr, spec))
1565 return buf;
1566
1567 do {
1568 switch (fmt[count++]) {
1569 case 'a':
1570 flags |= ESCAPE_ANY;
1571 break;
1572 case 'c':
1573 flags |= ESCAPE_SPECIAL;
1574 break;
1575 case 'h':
1576 flags |= ESCAPE_HEX;
1577 break;
1578 case 'n':
1579 flags |= ESCAPE_NULL;
1580 break;
1581 case 'o':
1582 flags |= ESCAPE_OCTAL;
1583 break;
1584 case 'p':
1585 flags |= ESCAPE_NP;
1586 break;
1587 case 's':
1588 flags |= ESCAPE_SPACE;
1589 break;
1590 default:
1591 found = false;
1592 break;
1593 }
1594 } while (found);
1595
1596 if (!flags)
1597 flags = ESCAPE_ANY_NP;
1598
1599 len = spec.field_width < 0 ? 1 : spec.field_width;
1600
1601 /*
1602 * string_escape_mem() writes as many characters as it can to
1603 * the given buffer, and returns the total size of the output
1604 * had the buffer been big enough.
1605 */
1606 buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL);
1607
1608 return buf;
1609 }
1610
1611 static char *va_format(char *buf, char *end, struct va_format *va_fmt,
1612 struct printf_spec spec, const char *fmt)
1613 {
1614 va_list va;
1615
1616 if (check_pointer(&buf, end, va_fmt, spec))
1617 return buf;
1618
1619 va_copy(va, *va_fmt->va);
1620 buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va);
1621 va_end(va);
1622
1623 return buf;
1624 }
1625
1626 static noinline_for_stack
1627 char *uuid_string(char *buf, char *end, const u8 *addr,
1628 struct printf_spec spec, const char *fmt)
1629 {
1630 char uuid[UUID_STRING_LEN + 1];
1631 char *p = uuid;
1632 int i;
1633 const u8 *index = uuid_index;
1634 bool uc = false;
1635
1636 if (check_pointer(&buf, end, addr, spec))
1637 return buf;
1638
1639 switch (*(++fmt)) {
1640 case 'L':
1641 uc = true; /* fall-through */
1642 case 'l':
1643 index = guid_index;
1644 break;
1645 case 'B':
1646 uc = true;
1647 break;
1648 }
1649
1650 for (i = 0; i < 16; i++) {
1651 if (uc)
1652 p = hex_byte_pack_upper(p, addr[index[i]]);
1653 else
1654 p = hex_byte_pack(p, addr[index[i]]);
1655 switch (i) {
1656 case 3:
1657 case 5:
1658 case 7:
1659 case 9:
1660 *p++ = '-';
1661 break;
1662 }
1663 }
1664
1665 *p = 0;
1666
1667 return string_nocheck(buf, end, uuid, spec);
1668 }
1669
1670 static noinline_for_stack
1671 char *netdev_bits(char *buf, char *end, const void *addr,
1672 struct printf_spec spec, const char *fmt)
1673 {
1674 unsigned long long num;
1675 int size;
1676
1677 if (check_pointer(&buf, end, addr, spec))
1678 return buf;
1679
1680 switch (fmt[1]) {
1681 case 'F':
1682 num = *(const netdev_features_t *)addr;
1683 size = sizeof(netdev_features_t);
1684 break;
1685 default:
1686 return error_string(buf, end, "(%pN?)", spec);
1687 }
1688
1689 return special_hex_number(buf, end, num, size);
1690 }
1691
1692 static noinline_for_stack
1693 char *address_val(char *buf, char *end, const void *addr,
1694 struct printf_spec spec, const char *fmt)
1695 {
1696 unsigned long long num;
1697 int size;
1698
1699 if (check_pointer(&buf, end, addr, spec))
1700 return buf;
1701
1702 switch (fmt[1]) {
1703 case 'd':
1704 num = *(const dma_addr_t *)addr;
1705 size = sizeof(dma_addr_t);
1706 break;
1707 case 'p':
1708 default:
1709 num = *(const phys_addr_t *)addr;
1710 size = sizeof(phys_addr_t);
1711 break;
1712 }
1713
1714 return special_hex_number(buf, end, num, size);
1715 }
1716
1717 static noinline_for_stack
1718 char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1719 {
1720 int year = tm->tm_year + (r ? 0 : 1900);
1721 int mon = tm->tm_mon + (r ? 0 : 1);
1722
1723 buf = number(buf, end, year, default_dec04_spec);
1724 if (buf < end)
1725 *buf = '-';
1726 buf++;
1727
1728 buf = number(buf, end, mon, default_dec02_spec);
1729 if (buf < end)
1730 *buf = '-';
1731 buf++;
1732
1733 return number(buf, end, tm->tm_mday, default_dec02_spec);
1734 }
1735
1736 static noinline_for_stack
1737 char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r)
1738 {
1739 buf = number(buf, end, tm->tm_hour, default_dec02_spec);
1740 if (buf < end)
1741 *buf = ':';
1742 buf++;
1743
1744 buf = number(buf, end, tm->tm_min, default_dec02_spec);
1745 if (buf < end)
1746 *buf = ':';
1747 buf++;
1748
1749 return number(buf, end, tm->tm_sec, default_dec02_spec);
1750 }
1751
1752 static noinline_for_stack
1753 char *rtc_str(char *buf, char *end, const struct rtc_time *tm,
1754 struct printf_spec spec, const char *fmt)
1755 {
1756 bool have_t = true, have_d = true;
1757 bool raw = false;
1758 int count = 2;
1759
1760 if (check_pointer(&buf, end, tm, spec))
1761 return buf;
1762
1763 switch (fmt[count]) {
1764 case 'd':
1765 have_t = false;
1766 count++;
1767 break;
1768 case 't':
1769 have_d = false;
1770 count++;
1771 break;
1772 }
1773
1774 raw = fmt[count] == 'r';
1775
1776 if (have_d)
1777 buf = date_str(buf, end, tm, raw);
1778 if (have_d && have_t) {
1779 /* Respect ISO 8601 */
1780 if (buf < end)
1781 *buf = 'T';
1782 buf++;
1783 }
1784 if (have_t)
1785 buf = time_str(buf, end, tm, raw);
1786
1787 return buf;
1788 }
1789
1790 static noinline_for_stack
1791 char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec,
1792 const char *fmt)
1793 {
1794 switch (fmt[1]) {
1795 case 'R':
1796 return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt);
1797 default:
1798 return error_string(buf, end, "(%ptR?)", spec);
1799 }
1800 }
1801
1802 static noinline_for_stack
1803 char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec,
1804 const char *fmt)
1805 {
1806 if (!IS_ENABLED(CONFIG_HAVE_CLK))
1807 return error_string(buf, end, "(%pC?)", spec);
1808
1809 if (check_pointer(&buf, end, clk, spec))
1810 return buf;
1811
1812 switch (fmt[1]) {
1813 case 'n':
1814 default:
1815 #ifdef CONFIG_COMMON_CLK
1816 return string(buf, end, __clk_get_name(clk), spec);
1817 #else
1818 return ptr_to_id(buf, end, clk, spec);
1819 #endif
1820 }
1821 }
1822
1823 static
1824 char *format_flags(char *buf, char *end, unsigned long flags,
1825 const struct trace_print_flags *names)
1826 {
1827 unsigned long mask;
1828
1829 for ( ; flags && names->name; names++) {
1830 mask = names->mask;
1831 if ((flags & mask) != mask)
1832 continue;
1833
1834 buf = string(buf, end, names->name, default_str_spec);
1835
1836 flags &= ~mask;
1837 if (flags) {
1838 if (buf < end)
1839 *buf = '|';
1840 buf++;
1841 }
1842 }
1843
1844 if (flags)
1845 buf = number(buf, end, flags, default_flag_spec);
1846
1847 return buf;
1848 }
1849
1850 static noinline_for_stack
1851 char *flags_string(char *buf, char *end, void *flags_ptr,
1852 struct printf_spec spec, const char *fmt)
1853 {
1854 unsigned long flags;
1855 const struct trace_print_flags *names;
1856
1857 if (check_pointer(&buf, end, flags_ptr, spec))
1858 return buf;
1859
1860 switch (fmt[1]) {
1861 case 'p':
1862 flags = *(unsigned long *)flags_ptr;
1863 /* Remove zone id */
1864 flags &= (1UL << NR_PAGEFLAGS) - 1;
1865 names = pageflag_names;
1866 break;
1867 case 'v':
1868 flags = *(unsigned long *)flags_ptr;
1869 names = vmaflag_names;
1870 break;
1871 case 'g':
1872 flags = *(gfp_t *)flags_ptr;
1873 names = gfpflag_names;
1874 break;
1875 default:
1876 return error_string(buf, end, "(%pG?)", spec);
1877 }
1878
1879 return format_flags(buf, end, flags, names);
1880 }
1881
1882 static const char *device_node_name_for_depth(const struct device_node *np, int depth)
1883 {
1884 for ( ; np && depth; depth--)
1885 np = np->parent;
1886
1887 return kbasename(np->full_name);
1888 }
1889
1890 static noinline_for_stack
1891 char *device_node_gen_full_name(const struct device_node *np, char *buf, char *end)
1892 {
1893 int depth;
1894 const struct device_node *parent = np->parent;
1895
1896 /* special case for root node */
1897 if (!parent)
1898 return string_nocheck(buf, end, "/", default_str_spec);
1899
1900 for (depth = 0; parent->parent; depth++)
1901 parent = parent->parent;
1902
1903 for ( ; depth >= 0; depth--) {
1904 buf = string_nocheck(buf, end, "/", default_str_spec);
1905 buf = string(buf, end, device_node_name_for_depth(np, depth),
1906 default_str_spec);
1907 }
1908 return buf;
1909 }
1910
1911 static noinline_for_stack
1912 char *device_node_string(char *buf, char *end, struct device_node *dn,
1913 struct printf_spec spec, const char *fmt)
1914 {
1915 char tbuf[sizeof("xxxx") + 1];
1916 const char *p;
1917 int ret;
1918 char *buf_start = buf;
1919 struct property *prop;
1920 bool has_mult, pass;
1921 static const struct printf_spec num_spec = {
1922 .flags = SMALL,
1923 .field_width = -1,
1924 .precision = -1,
1925 .base = 10,
1926 };
1927
1928 struct printf_spec str_spec = spec;
1929 str_spec.field_width = -1;
1930
1931 if (!IS_ENABLED(CONFIG_OF))
1932 return error_string(buf, end, "(%pOF?)", spec);
1933
1934 if (check_pointer(&buf, end, dn, spec))
1935 return buf;
1936
1937 /* simple case without anything any more format specifiers */
1938 fmt++;
1939 if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0)
1940 fmt = "f";
1941
1942 for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) {
1943 int precision;
1944 if (pass) {
1945 if (buf < end)
1946 *buf = ':';
1947 buf++;
1948 }
1949
1950 switch (*fmt) {
1951 case 'f': /* full_name */
1952 buf = device_node_gen_full_name(dn, buf, end);
1953 break;
1954 case 'n': /* name */
1955 p = kbasename(of_node_full_name(dn));
1956 precision = str_spec.precision;
1957 str_spec.precision = strchrnul(p, '@') - p;
1958 buf = string(buf, end, p, str_spec);
1959 str_spec.precision = precision;
1960 break;
1961 case 'p': /* phandle */
1962 buf = number(buf, end, (unsigned int)dn->phandle, num_spec);
1963 break;
1964 case 'P': /* path-spec */
1965 p = kbasename(of_node_full_name(dn));
1966 if (!p[1])
1967 p = "/";
1968 buf = string(buf, end, p, str_spec);
1969 break;
1970 case 'F': /* flags */
1971 tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-';
1972 tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-';
1973 tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-';
1974 tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-';
1975 tbuf[4] = 0;
1976 buf = string_nocheck(buf, end, tbuf, str_spec);
1977 break;
1978 case 'c': /* major compatible string */
1979 ret = of_property_read_string(dn, "compatible", &p);
1980 if (!ret)
1981 buf = string(buf, end, p, str_spec);
1982 break;
1983 case 'C': /* full compatible string */
1984 has_mult = false;
1985 of_property_for_each_string(dn, "compatible", prop, p) {
1986 if (has_mult)
1987 buf = string_nocheck(buf, end, ",", str_spec);
1988 buf = string_nocheck(buf, end, "\"", str_spec);
1989 buf = string(buf, end, p, str_spec);
1990 buf = string_nocheck(buf, end, "\"", str_spec);
1991
1992 has_mult = true;
1993 }
1994 break;
1995 default:
1996 break;
1997 }
1998 }
1999
2000 return widen_string(buf, buf - buf_start, end, spec);
2001 }
2002
2003 static char *kobject_string(char *buf, char *end, void *ptr,
2004 struct printf_spec spec, const char *fmt)
2005 {
2006 switch (fmt[1]) {
2007 case 'F':
2008 return device_node_string(buf, end, ptr, spec, fmt + 1);
2009 }
2010
2011 return error_string(buf, end, "(%pO?)", spec);
2012 }
2013
2014 #ifdef CONFIG_KMSG_IDS
2015
2016 unsigned long long __jhash_string(const char *str);
2017
2018 static noinline_for_stack
2019 char *jhash_string(char *buf, char *end, const char *str, const char *fmt)
2020 {
2021 struct printf_spec spec;
2022 unsigned long long num;
2023
2024 num = __jhash_string(str);
2025
2026 spec.type = FORMAT_TYPE_PTR;
2027 spec.field_width = 6;
2028 spec.flags = SMALL | ZEROPAD;
2029 spec.base = 16;
2030 spec.precision = -1;
2031
2032 return number(buf, end, num, spec);
2033 }
2034
2035 #endif
2036
2037 /*
2038 * Show a '%p' thing. A kernel extension is that the '%p' is followed
2039 * by an extra set of alphanumeric characters that are extended format
2040 * specifiers.
2041 *
2042 * Please update scripts/checkpatch.pl when adding/removing conversion
2043 * characters. (Search for "check for vsprintf extension").
2044 *
2045 * Right now we handle:
2046 *
2047 * - 'S' For symbolic direct pointers (or function descriptors) with offset
2048 * - 's' For symbolic direct pointers (or function descriptors) without offset
2049 * - 'F' Same as 'S'
2050 * - 'f' Same as 's'
2051 * - '[FfSs]R' as above with __builtin_extract_return_addr() translation
2052 * - 'B' For backtraced symbolic direct pointers with offset
2053 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
2054 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
2055 * - 'b[l]' For a bitmap, the number of bits is determined by the field
2056 * width which must be explicitly specified either as part of the
2057 * format string '%32b[l]' or through '%*b[l]', [l] selects
2058 * range-list format instead of hex format
2059 * - 'M' For a 6-byte MAC address, it prints the address in the
2060 * usual colon-separated hex notation
2061 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
2062 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
2063 * with a dash-separated hex notation
2064 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
2065 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
2066 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
2067 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
2068 * [S][pfs]
2069 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2070 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2071 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
2072 * IPv6 omits the colons (01020304...0f)
2073 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
2074 * [S][pfs]
2075 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2076 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2077 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
2078 * - 'I[6S]c' for IPv6 addresses printed as specified by
2079 * http://tools.ietf.org/html/rfc5952
2080 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
2081 * of the following flags (see string_escape_mem() for the
2082 * details):
2083 * a - ESCAPE_ANY
2084 * c - ESCAPE_SPECIAL
2085 * h - ESCAPE_HEX
2086 * n - ESCAPE_NULL
2087 * o - ESCAPE_OCTAL
2088 * p - ESCAPE_NP
2089 * s - ESCAPE_SPACE
2090 * By default ESCAPE_ANY_NP is used.
2091 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
2092 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
2093 * Options for %pU are:
2094 * b big endian lower case hex (default)
2095 * B big endian UPPER case hex
2096 * l little endian lower case hex
2097 * L little endian UPPER case hex
2098 * big endian output byte order is:
2099 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
2100 * little endian output byte order is:
2101 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
2102 * - 'V' For a struct va_format which contains a format string * and va_list *,
2103 * call vsnprintf(->format, *->va_list).
2104 * Implements a "recursive vsnprintf".
2105 * Do not use this feature without some mechanism to verify the
2106 * correctness of the format string and va_list arguments.
2107 * - 'K' For a kernel pointer that should be hidden from unprivileged users
2108 * - 'NF' For a netdev_features_t
2109 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
2110 * a certain separator (' ' by default):
2111 * C colon
2112 * D dash
2113 * N no separator
2114 * The maximum supported length is 64 bytes of the input. Consider
2115 * to use print_hex_dump() for the larger input.
2116 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
2117 * (default assumed to be phys_addr_t, passed by reference)
2118 * - 'd[234]' For a dentry name (optionally 2-4 last components)
2119 * - 'D[234]' Same as 'd' but for a struct file
2120 * - 'g' For block_device name (gendisk + partition number)
2121 * - 't[R][dt][r]' For time and date as represented:
2122 * R struct rtc_time
2123 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
2124 * (legacy clock framework) of the clock
2125 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
2126 * (legacy clock framework) of the clock
2127 * - 'G' For flags to be printed as a collection of symbolic strings that would
2128 * construct the specific value. Supported flags given by option:
2129 * p page flags (see struct page) given as pointer to unsigned long
2130 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
2131 * v vma flags (VM_*) given as pointer to unsigned long
2132 * - 'OF[fnpPcCF]' For a device tree object
2133 * Without any optional arguments prints the full_name
2134 * f device node full_name
2135 * n device node name
2136 * p device node phandle
2137 * P device node path spec (name + @unit)
2138 * F device node flags
2139 * c major compatible string
2140 * C full compatible string
2141 * - 'j' Kernel message catalog jhash for System z
2142 * - 'x' For printing the address. Equivalent to "%lx".
2143 *
2144 * ** When making changes please also update:
2145 * Documentation/core-api/printk-formats.rst
2146 *
2147 * Note: The default behaviour (unadorned %p) is to hash the address,
2148 * rendering it useful as a unique identifier.
2149 */
2150 static noinline_for_stack
2151 char *pointer(const char *fmt, char *buf, char *end, void *ptr,
2152 struct printf_spec spec)
2153 {
2154 switch (*fmt) {
2155 case 'F':
2156 case 'f':
2157 case 'S':
2158 case 's':
2159 ptr = dereference_symbol_descriptor(ptr);
2160 /* Fallthrough */
2161 case 'B':
2162 return symbol_string(buf, end, ptr, spec, fmt);
2163 case 'R':
2164 case 'r':
2165 return resource_string(buf, end, ptr, spec, fmt);
2166 case 'h':
2167 return hex_string(buf, end, ptr, spec, fmt);
2168 case 'b':
2169 switch (fmt[1]) {
2170 case 'l':
2171 return bitmap_list_string(buf, end, ptr, spec, fmt);
2172 default:
2173 return bitmap_string(buf, end, ptr, spec, fmt);
2174 }
2175 case 'M': /* Colon separated: 00:01:02:03:04:05 */
2176 case 'm': /* Contiguous: 000102030405 */
2177 /* [mM]F (FDDI) */
2178 /* [mM]R (Reverse order; Bluetooth) */
2179 return mac_address_string(buf, end, ptr, spec, fmt);
2180 case 'I': /* Formatted IP supported
2181 * 4: 1.2.3.4
2182 * 6: 0001:0203:...:0708
2183 * 6c: 1::708 or 1::1.2.3.4
2184 */
2185 case 'i': /* Contiguous:
2186 * 4: 001.002.003.004
2187 * 6: 000102...0f
2188 */
2189 return ip_addr_string(buf, end, ptr, spec, fmt);
2190 case 'E':
2191 return escaped_string(buf, end, ptr, spec, fmt);
2192 case 'U':
2193 return uuid_string(buf, end, ptr, spec, fmt);
2194 case 'V':
2195 return va_format(buf, end, ptr, spec, fmt);
2196 case 'K':
2197 return restricted_pointer(buf, end, ptr, spec);
2198 case 'N':
2199 return netdev_bits(buf, end, ptr, spec, fmt);
2200 case 'a':
2201 return address_val(buf, end, ptr, spec, fmt);
2202 case 'd':
2203 return dentry_name(buf, end, ptr, spec, fmt);
2204 case 't':
2205 return time_and_date(buf, end, ptr, spec, fmt);
2206 case 'C':
2207 return clock(buf, end, ptr, spec, fmt);
2208 case 'D':
2209 return file_dentry_name(buf, end, ptr, spec, fmt);
2210 #ifdef CONFIG_BLOCK
2211 case 'g':
2212 return bdev_name(buf, end, ptr, spec, fmt);
2213 #endif
2214
2215 case 'G':
2216 return flags_string(buf, end, ptr, spec, fmt);
2217 case 'O':
2218 return kobject_string(buf, end, ptr, spec, fmt);
2219 case 'x':
2220 return pointer_string(buf, end, ptr, spec);
2221 #ifdef CONFIG_KMSG_IDS
2222 case 'j':
2223 return jhash_string(buf, end, ptr, fmt);
2224 #endif
2225 }
2226
2227 /* default is to _not_ leak addresses, hash before printing */
2228 return ptr_to_id(buf, end, ptr, spec);
2229 }
2230
2231 /*
2232 * Helper function to decode printf style format.
2233 * Each call decode a token from the format and return the
2234 * number of characters read (or likely the delta where it wants
2235 * to go on the next call).
2236 * The decoded token is returned through the parameters
2237 *
2238 * 'h', 'l', or 'L' for integer fields
2239 * 'z' support added 23/7/1999 S.H.
2240 * 'z' changed to 'Z' --davidm 1/25/99
2241 * 'Z' changed to 'z' --adobriyan 2017-01-25
2242 * 't' added for ptrdiff_t
2243 *
2244 * @fmt: the format string
2245 * @type of the token returned
2246 * @flags: various flags such as +, -, # tokens..
2247 * @field_width: overwritten width
2248 * @base: base of the number (octal, hex, ...)
2249 * @precision: precision of a number
2250 * @qualifier: qualifier of a number (long, size_t, ...)
2251 */
2252 static noinline_for_stack
2253 int format_decode(const char *fmt, struct printf_spec *spec)
2254 {
2255 const char *start = fmt;
2256 char qualifier;
2257
2258 /* we finished early by reading the field width */
2259 if (spec->type == FORMAT_TYPE_WIDTH) {
2260 if (spec->field_width < 0) {
2261 spec->field_width = -spec->field_width;
2262 spec->flags |= LEFT;
2263 }
2264 spec->type = FORMAT_TYPE_NONE;
2265 goto precision;
2266 }
2267
2268 /* we finished early by reading the precision */
2269 if (spec->type == FORMAT_TYPE_PRECISION) {
2270 if (spec->precision < 0)
2271 spec->precision = 0;
2272
2273 spec->type = FORMAT_TYPE_NONE;
2274 goto qualifier;
2275 }
2276
2277 /* By default */
2278 spec->type = FORMAT_TYPE_NONE;
2279
2280 for (; *fmt ; ++fmt) {
2281 if (*fmt == '%')
2282 break;
2283 }
2284
2285 /* Return the current non-format string */
2286 if (fmt != start || !*fmt)
2287 return fmt - start;
2288
2289 /* Process flags */
2290 spec->flags = 0;
2291
2292 while (1) { /* this also skips first '%' */
2293 bool found = true;
2294
2295 ++fmt;
2296
2297 switch (*fmt) {
2298 case '-': spec->flags |= LEFT; break;
2299 case '+': spec->flags |= PLUS; break;
2300 case ' ': spec->flags |= SPACE; break;
2301 case '#': spec->flags |= SPECIAL; break;
2302 case '0': spec->flags |= ZEROPAD; break;
2303 default: found = false;
2304 }
2305
2306 if (!found)
2307 break;
2308 }
2309
2310 /* get field width */
2311 spec->field_width = -1;
2312
2313 if (isdigit(*fmt))
2314 spec->field_width = skip_atoi(&fmt);
2315 else if (*fmt == '*') {
2316 /* it's the next argument */
2317 spec->type = FORMAT_TYPE_WIDTH;
2318 return ++fmt - start;
2319 }
2320
2321 precision:
2322 /* get the precision */
2323 spec->precision = -1;
2324 if (*fmt == '.') {
2325 ++fmt;
2326 if (isdigit(*fmt)) {
2327 spec->precision = skip_atoi(&fmt);
2328 if (spec->precision < 0)
2329 spec->precision = 0;
2330 } else if (*fmt == '*') {
2331 /* it's the next argument */
2332 spec->type = FORMAT_TYPE_PRECISION;
2333 return ++fmt - start;
2334 }
2335 }
2336
2337 qualifier:
2338 /* get the conversion qualifier */
2339 qualifier = 0;
2340 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
2341 *fmt == 'z' || *fmt == 't') {
2342 qualifier = *fmt++;
2343 if (unlikely(qualifier == *fmt)) {
2344 if (qualifier == 'l') {
2345 qualifier = 'L';
2346 ++fmt;
2347 } else if (qualifier == 'h') {
2348 qualifier = 'H';
2349 ++fmt;
2350 }
2351 }
2352 }
2353
2354 /* default base */
2355 spec->base = 10;
2356 switch (*fmt) {
2357 case 'c':
2358 spec->type = FORMAT_TYPE_CHAR;
2359 return ++fmt - start;
2360
2361 case 's':
2362 spec->type = FORMAT_TYPE_STR;
2363 return ++fmt - start;
2364
2365 case 'p':
2366 spec->type = FORMAT_TYPE_PTR;
2367 return ++fmt - start;
2368
2369 case '%':
2370 spec->type = FORMAT_TYPE_PERCENT_CHAR;
2371 return ++fmt - start;
2372
2373 /* integer number formats - set up the flags and "break" */
2374 case 'o':
2375 spec->base = 8;
2376 break;
2377
2378 case 'x':
2379 spec->flags |= SMALL;
2380 /* fall through */
2381
2382 case 'X':
2383 spec->base = 16;
2384 break;
2385
2386 case 'd':
2387 case 'i':
2388 spec->flags |= SIGN;
2389 case 'u':
2390 break;
2391
2392 case 'n':
2393 /*
2394 * Since %n poses a greater security risk than
2395 * utility, treat it as any other invalid or
2396 * unsupported format specifier.
2397 */
2398 /* Fall-through */
2399
2400 default:
2401 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt);
2402 spec->type = FORMAT_TYPE_INVALID;
2403 return fmt - start;
2404 }
2405
2406 if (qualifier == 'L')
2407 spec->type = FORMAT_TYPE_LONG_LONG;
2408 else if (qualifier == 'l') {
2409 BUILD_BUG_ON(FORMAT_TYPE_ULONG + SIGN != FORMAT_TYPE_LONG);
2410 spec->type = FORMAT_TYPE_ULONG + (spec->flags & SIGN);
2411 } else if (qualifier == 'z') {
2412 spec->type = FORMAT_TYPE_SIZE_T;
2413 } else if (qualifier == 't') {
2414 spec->type = FORMAT_TYPE_PTRDIFF;
2415 } else if (qualifier == 'H') {
2416 BUILD_BUG_ON(FORMAT_TYPE_UBYTE + SIGN != FORMAT_TYPE_BYTE);
2417 spec->type = FORMAT_TYPE_UBYTE + (spec->flags & SIGN);
2418 } else if (qualifier == 'h') {
2419 BUILD_BUG_ON(FORMAT_TYPE_USHORT + SIGN != FORMAT_TYPE_SHORT);
2420 spec->type = FORMAT_TYPE_USHORT + (spec->flags & SIGN);
2421 } else {
2422 BUILD_BUG_ON(FORMAT_TYPE_UINT + SIGN != FORMAT_TYPE_INT);
2423 spec->type = FORMAT_TYPE_UINT + (spec->flags & SIGN);
2424 }
2425
2426 return ++fmt - start;
2427 }
2428
2429 static void
2430 set_field_width(struct printf_spec *spec, int width)
2431 {
2432 spec->field_width = width;
2433 if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) {
2434 spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX);
2435 }
2436 }
2437
2438 static void
2439 set_precision(struct printf_spec *spec, int prec)
2440 {
2441 spec->precision = prec;
2442 if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) {
2443 spec->precision = clamp(prec, 0, PRECISION_MAX);
2444 }
2445 }
2446
2447 /**
2448 * vsnprintf - Format a string and place it in a buffer
2449 * @buf: The buffer to place the result into
2450 * @size: The size of the buffer, including the trailing null space
2451 * @fmt: The format string to use
2452 * @args: Arguments for the format string
2453 *
2454 * This function generally follows C99 vsnprintf, but has some
2455 * extensions and a few limitations:
2456 *
2457 * - ``%n`` is unsupported
2458 * - ``%p*`` is handled by pointer()
2459 *
2460 * See pointer() or Documentation/core-api/printk-formats.rst for more
2461 * extensive description.
2462 *
2463 * **Please update the documentation in both places when making changes**
2464 *
2465 * The return value is the number of characters which would
2466 * be generated for the given input, excluding the trailing
2467 * '\0', as per ISO C99. If you want to have the exact
2468 * number of characters written into @buf as return value
2469 * (not including the trailing '\0'), use vscnprintf(). If the
2470 * return is greater than or equal to @size, the resulting
2471 * string is truncated.
2472 *
2473 * If you're not already dealing with a va_list consider using snprintf().
2474 */
2475 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
2476 {
2477 unsigned long long num;
2478 char *str, *end;
2479 struct printf_spec spec = {0};
2480
2481 /* Reject out-of-range values early. Large positive sizes are
2482 used for unknown buffer sizes. */
2483 if (WARN_ON_ONCE(size > INT_MAX))
2484 return 0;
2485
2486 str = buf;
2487 end = buf + size;
2488
2489 /* Make sure end is always >= buf */
2490 if (end < buf) {
2491 end = ((void *)-1);
2492 size = end - buf;
2493 }
2494
2495 while (*fmt) {
2496 const char *old_fmt = fmt;
2497 int read = format_decode(fmt, &spec);
2498
2499 fmt += read;
2500
2501 switch (spec.type) {
2502 case FORMAT_TYPE_NONE: {
2503 int copy = read;
2504 if (str < end) {
2505 if (copy > end - str)
2506 copy = end - str;
2507 memcpy(str, old_fmt, copy);
2508 }
2509 str += read;
2510 break;
2511 }
2512
2513 case FORMAT_TYPE_WIDTH:
2514 set_field_width(&spec, va_arg(args, int));
2515 break;
2516
2517 case FORMAT_TYPE_PRECISION:
2518 set_precision(&spec, va_arg(args, int));
2519 break;
2520
2521 case FORMAT_TYPE_CHAR: {
2522 char c;
2523
2524 if (!(spec.flags & LEFT)) {
2525 while (--spec.field_width > 0) {
2526 if (str < end)
2527 *str = ' ';
2528 ++str;
2529
2530 }
2531 }
2532 c = (unsigned char) va_arg(args, int);
2533 if (str < end)
2534 *str = c;
2535 ++str;
2536 while (--spec.field_width > 0) {
2537 if (str < end)
2538 *str = ' ';
2539 ++str;
2540 }
2541 break;
2542 }
2543
2544 case FORMAT_TYPE_STR:
2545 str = string(str, end, va_arg(args, char *), spec);
2546 break;
2547
2548 case FORMAT_TYPE_PTR:
2549 str = pointer(fmt, str, end, va_arg(args, void *),
2550 spec);
2551 while (isalnum(*fmt))
2552 fmt++;
2553 break;
2554
2555 case FORMAT_TYPE_PERCENT_CHAR:
2556 if (str < end)
2557 *str = '%';
2558 ++str;
2559 break;
2560
2561 case FORMAT_TYPE_INVALID:
2562 /*
2563 * Presumably the arguments passed gcc's type
2564 * checking, but there is no safe or sane way
2565 * for us to continue parsing the format and
2566 * fetching from the va_list; the remaining
2567 * specifiers and arguments would be out of
2568 * sync.
2569 */
2570 goto out;
2571
2572 default:
2573 switch (spec.type) {
2574 case FORMAT_TYPE_LONG_LONG:
2575 num = va_arg(args, long long);
2576 break;
2577 case FORMAT_TYPE_ULONG:
2578 num = va_arg(args, unsigned long);
2579 break;
2580 case FORMAT_TYPE_LONG:
2581 num = va_arg(args, long);
2582 break;
2583 case FORMAT_TYPE_SIZE_T:
2584 if (spec.flags & SIGN)
2585 num = va_arg(args, ssize_t);
2586 else
2587 num = va_arg(args, size_t);
2588 break;
2589 case FORMAT_TYPE_PTRDIFF:
2590 num = va_arg(args, ptrdiff_t);
2591 break;
2592 case FORMAT_TYPE_UBYTE:
2593 num = (unsigned char) va_arg(args, int);
2594 break;
2595 case FORMAT_TYPE_BYTE:
2596 num = (signed char) va_arg(args, int);
2597 break;
2598 case FORMAT_TYPE_USHORT:
2599 num = (unsigned short) va_arg(args, int);
2600 break;
2601 case FORMAT_TYPE_SHORT:
2602 num = (short) va_arg(args, int);
2603 break;
2604 case FORMAT_TYPE_INT:
2605 num = (int) va_arg(args, int);
2606 break;
2607 default:
2608 num = va_arg(args, unsigned int);
2609 }
2610
2611 str = number(str, end, num, spec);
2612 }
2613 }
2614
2615 out:
2616 if (size > 0) {
2617 if (str < end)
2618 *str = '\0';
2619 else
2620 end[-1] = '\0';
2621 }
2622
2623 /* the trailing null byte doesn't count towards the total */
2624 return str-buf;
2625
2626 }
2627 EXPORT_SYMBOL(vsnprintf);
2628
2629 /**
2630 * vscnprintf - Format a string and place it in a buffer
2631 * @buf: The buffer to place the result into
2632 * @size: The size of the buffer, including the trailing null space
2633 * @fmt: The format string to use
2634 * @args: Arguments for the format string
2635 *
2636 * The return value is the number of characters which have been written into
2637 * the @buf not including the trailing '\0'. If @size is == 0 the function
2638 * returns 0.
2639 *
2640 * If you're not already dealing with a va_list consider using scnprintf().
2641 *
2642 * See the vsnprintf() documentation for format string extensions over C99.
2643 */
2644 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
2645 {
2646 int i;
2647
2648 i = vsnprintf(buf, size, fmt, args);
2649
2650 if (likely(i < size))
2651 return i;
2652 if (size != 0)
2653 return size - 1;
2654 return 0;
2655 }
2656 EXPORT_SYMBOL(vscnprintf);
2657
2658 /**
2659 * snprintf - Format a string and place it in a buffer
2660 * @buf: The buffer to place the result into
2661 * @size: The size of the buffer, including the trailing null space
2662 * @fmt: The format string to use
2663 * @...: Arguments for the format string
2664 *
2665 * The return value is the number of characters which would be
2666 * generated for the given input, excluding the trailing null,
2667 * as per ISO C99. If the return is greater than or equal to
2668 * @size, the resulting string is truncated.
2669 *
2670 * See the vsnprintf() documentation for format string extensions over C99.
2671 */
2672 int snprintf(char *buf, size_t size, const char *fmt, ...)
2673 {
2674 va_list args;
2675 int i;
2676
2677 va_start(args, fmt);
2678 i = vsnprintf(buf, size, fmt, args);
2679 va_end(args);
2680
2681 return i;
2682 }
2683 EXPORT_SYMBOL(snprintf);
2684
2685 /**
2686 * scnprintf - Format a string and place it in a buffer
2687 * @buf: The buffer to place the result into
2688 * @size: The size of the buffer, including the trailing null space
2689 * @fmt: The format string to use
2690 * @...: Arguments for the format string
2691 *
2692 * The return value is the number of characters written into @buf not including
2693 * the trailing '\0'. If @size is == 0 the function returns 0.
2694 */
2695
2696 int scnprintf(char *buf, size_t size, const char *fmt, ...)
2697 {
2698 va_list args;
2699 int i;
2700
2701 va_start(args, fmt);
2702 i = vscnprintf(buf, size, fmt, args);
2703 va_end(args);
2704
2705 return i;
2706 }
2707 EXPORT_SYMBOL(scnprintf);
2708
2709 /**
2710 * vsprintf - Format a string and place it in a buffer
2711 * @buf: The buffer to place the result into
2712 * @fmt: The format string to use
2713 * @args: Arguments for the format string
2714 *
2715 * The function returns the number of characters written
2716 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2717 * buffer overflows.
2718 *
2719 * If you're not already dealing with a va_list consider using sprintf().
2720 *
2721 * See the vsnprintf() documentation for format string extensions over C99.
2722 */
2723 int vsprintf(char *buf, const char *fmt, va_list args)
2724 {
2725 return vsnprintf(buf, INT_MAX, fmt, args);
2726 }
2727 EXPORT_SYMBOL(vsprintf);
2728
2729 /**
2730 * sprintf - Format a string and place it in a buffer
2731 * @buf: The buffer to place the result into
2732 * @fmt: The format string to use
2733 * @...: Arguments for the format string
2734 *
2735 * The function returns the number of characters written
2736 * into @buf. Use snprintf() or scnprintf() in order to avoid
2737 * buffer overflows.
2738 *
2739 * See the vsnprintf() documentation for format string extensions over C99.
2740 */
2741 int sprintf(char *buf, const char *fmt, ...)
2742 {
2743 va_list args;
2744 int i;
2745
2746 va_start(args, fmt);
2747 i = vsnprintf(buf, INT_MAX, fmt, args);
2748 va_end(args);
2749
2750 return i;
2751 }
2752 EXPORT_SYMBOL(sprintf);
2753
2754 #ifdef CONFIG_BINARY_PRINTF
2755 /*
2756 * bprintf service:
2757 * vbin_printf() - VA arguments to binary data
2758 * bstr_printf() - Binary data to text string
2759 */
2760
2761 /**
2762 * vbin_printf - Parse a format string and place args' binary value in a buffer
2763 * @bin_buf: The buffer to place args' binary value
2764 * @size: The size of the buffer(by words(32bits), not characters)
2765 * @fmt: The format string to use
2766 * @args: Arguments for the format string
2767 *
2768 * The format follows C99 vsnprintf, except %n is ignored, and its argument
2769 * is skipped.
2770 *
2771 * The return value is the number of words(32bits) which would be generated for
2772 * the given input.
2773 *
2774 * NOTE:
2775 * If the return value is greater than @size, the resulting bin_buf is NOT
2776 * valid for bstr_printf().
2777 */
2778 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
2779 {
2780 struct printf_spec spec = {0};
2781 char *str, *end;
2782 int width;
2783
2784 str = (char *)bin_buf;
2785 end = (char *)(bin_buf + size);
2786
2787 #define save_arg(type) \
2788 ({ \
2789 unsigned long long value; \
2790 if (sizeof(type) == 8) { \
2791 unsigned long long val8; \
2792 str = PTR_ALIGN(str, sizeof(u32)); \
2793 val8 = va_arg(args, unsigned long long); \
2794 if (str + sizeof(type) <= end) { \
2795 *(u32 *)str = *(u32 *)&val8; \
2796 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \
2797 } \
2798 value = val8; \
2799 } else { \
2800 unsigned int val4; \
2801 str = PTR_ALIGN(str, sizeof(type)); \
2802 val4 = va_arg(args, int); \
2803 if (str + sizeof(type) <= end) \
2804 *(typeof(type) *)str = (type)(long)val4; \
2805 value = (unsigned long long)val4; \
2806 } \
2807 str += sizeof(type); \
2808 value; \
2809 })
2810
2811 while (*fmt) {
2812 int read = format_decode(fmt, &spec);
2813
2814 fmt += read;
2815
2816 switch (spec.type) {
2817 case FORMAT_TYPE_NONE:
2818 case FORMAT_TYPE_PERCENT_CHAR:
2819 break;
2820 case FORMAT_TYPE_INVALID:
2821 goto out;
2822
2823 case FORMAT_TYPE_WIDTH:
2824 case FORMAT_TYPE_PRECISION:
2825 width = (int)save_arg(int);
2826 /* Pointers may require the width */
2827 if (*fmt == 'p')
2828 set_field_width(&spec, width);
2829 break;
2830
2831 case FORMAT_TYPE_CHAR:
2832 save_arg(char);
2833 break;
2834
2835 case FORMAT_TYPE_STR: {
2836 const char *save_str = va_arg(args, char *);
2837 const char *err_msg;
2838 size_t len;
2839
2840 err_msg = check_pointer_msg(save_str);
2841 if (err_msg)
2842 save_str = err_msg;
2843
2844 len = strlen(save_str) + 1;
2845 if (str + len < end)
2846 memcpy(str, save_str, len);
2847 str += len;
2848 break;
2849 }
2850
2851 case FORMAT_TYPE_PTR:
2852 /* Dereferenced pointers must be done now */
2853 switch (*fmt) {
2854 /* Dereference of functions is still OK */
2855 case 'S':
2856 case 's':
2857 case 'F':
2858 case 'f':
2859 case 'x':
2860 case 'K':
2861 save_arg(void *);
2862 break;
2863 default:
2864 if (!isalnum(*fmt)) {
2865 save_arg(void *);
2866 break;
2867 }
2868 str = pointer(fmt, str, end, va_arg(args, void *),
2869 spec);
2870 if (str + 1 < end)
2871 *str++ = '\0';
2872 else
2873 end[-1] = '\0'; /* Must be nul terminated */
2874 }
2875 /* skip all alphanumeric pointer suffixes */
2876 while (isalnum(*fmt))
2877 fmt++;
2878 break;
2879
2880 default:
2881 switch (spec.type) {
2882
2883 case FORMAT_TYPE_LONG_LONG:
2884 save_arg(long long);
2885 break;
2886 case FORMAT_TYPE_ULONG:
2887 case FORMAT_TYPE_LONG:
2888 save_arg(unsigned long);
2889 break;
2890 case FORMAT_TYPE_SIZE_T:
2891 save_arg(size_t);
2892 break;
2893 case FORMAT_TYPE_PTRDIFF:
2894 save_arg(ptrdiff_t);
2895 break;
2896 case FORMAT_TYPE_UBYTE:
2897 case FORMAT_TYPE_BYTE:
2898 save_arg(char);
2899 break;
2900 case FORMAT_TYPE_USHORT:
2901 case FORMAT_TYPE_SHORT:
2902 save_arg(short);
2903 break;
2904 default:
2905 save_arg(int);
2906 }
2907 }
2908 }
2909
2910 out:
2911 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
2912 #undef save_arg
2913 }
2914 EXPORT_SYMBOL_GPL(vbin_printf);
2915
2916 /**
2917 * bstr_printf - Format a string from binary arguments and place it in a buffer
2918 * @buf: The buffer to place the result into
2919 * @size: The size of the buffer, including the trailing null space
2920 * @fmt: The format string to use
2921 * @bin_buf: Binary arguments for the format string
2922 *
2923 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
2924 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
2925 * a binary buffer that generated by vbin_printf.
2926 *
2927 * The format follows C99 vsnprintf, but has some extensions:
2928 * see vsnprintf comment for details.
2929 *
2930 * The return value is the number of characters which would
2931 * be generated for the given input, excluding the trailing
2932 * '\0', as per ISO C99. If you want to have the exact
2933 * number of characters written into @buf as return value
2934 * (not including the trailing '\0'), use vscnprintf(). If the
2935 * return is greater than or equal to @size, the resulting
2936 * string is truncated.
2937 */
2938 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
2939 {
2940 struct printf_spec spec = {0};
2941 char *str, *end;
2942 const char *args = (const char *)bin_buf;
2943
2944 if (WARN_ON_ONCE(size > INT_MAX))
2945 return 0;
2946
2947 str = buf;
2948 end = buf + size;
2949
2950 #define get_arg(type) \
2951 ({ \
2952 typeof(type) value; \
2953 if (sizeof(type) == 8) { \
2954 args = PTR_ALIGN(args, sizeof(u32)); \
2955 *(u32 *)&value = *(u32 *)args; \
2956 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
2957 } else { \
2958 args = PTR_ALIGN(args, sizeof(type)); \
2959 value = *(typeof(type) *)args; \
2960 } \
2961 args += sizeof(type); \
2962 value; \
2963 })
2964
2965 /* Make sure end is always >= buf */
2966 if (end < buf) {
2967 end = ((void *)-1);
2968 size = end - buf;
2969 }
2970
2971 while (*fmt) {
2972 const char *old_fmt = fmt;
2973 int read = format_decode(fmt, &spec);
2974
2975 fmt += read;
2976
2977 switch (spec.type) {
2978 case FORMAT_TYPE_NONE: {
2979 int copy = read;
2980 if (str < end) {
2981 if (copy > end - str)
2982 copy = end - str;
2983 memcpy(str, old_fmt, copy);
2984 }
2985 str += read;
2986 break;
2987 }
2988
2989 case FORMAT_TYPE_WIDTH:
2990 set_field_width(&spec, get_arg(int));
2991 break;
2992
2993 case FORMAT_TYPE_PRECISION:
2994 set_precision(&spec, get_arg(int));
2995 break;
2996
2997 case FORMAT_TYPE_CHAR: {
2998 char c;
2999
3000 if (!(spec.flags & LEFT)) {
3001 while (--spec.field_width > 0) {
3002 if (str < end)
3003 *str = ' ';
3004 ++str;
3005 }
3006 }
3007 c = (unsigned char) get_arg(char);
3008 if (str < end)
3009 *str = c;
3010 ++str;
3011 while (--spec.field_width > 0) {
3012 if (str < end)
3013 *str = ' ';
3014 ++str;
3015 }
3016 break;
3017 }
3018
3019 case FORMAT_TYPE_STR: {
3020 const char *str_arg = args;
3021 args += strlen(str_arg) + 1;
3022 str = string(str, end, (char *)str_arg, spec);
3023 break;
3024 }
3025
3026 case FORMAT_TYPE_PTR: {
3027 bool process = false;
3028 int copy, len;
3029 /* Non function dereferences were already done */
3030 switch (*fmt) {
3031 case 'S':
3032 case 's':
3033 case 'F':
3034 case 'f':
3035 case 'x':
3036 case 'K':
3037 process = true;
3038 break;
3039 default:
3040 if (!isalnum(*fmt)) {
3041 process = true;
3042 break;
3043 }
3044 /* Pointer dereference was already processed */
3045 if (str < end) {
3046 len = copy = strlen(args);
3047 if (copy > end - str)
3048 copy = end - str;
3049 memcpy(str, args, copy);
3050 str += len;
3051 args += len + 1;
3052 }
3053 }
3054 if (process)
3055 str = pointer(fmt, str, end, get_arg(void *), spec);
3056
3057 while (isalnum(*fmt))
3058 fmt++;
3059 break;
3060 }
3061
3062 case FORMAT_TYPE_PERCENT_CHAR:
3063 if (str < end)
3064 *str = '%';
3065 ++str;
3066 break;
3067
3068 case FORMAT_TYPE_INVALID:
3069 goto out;
3070
3071 default: {
3072 unsigned long long num;
3073
3074 switch (spec.type) {
3075
3076 case FORMAT_TYPE_LONG_LONG:
3077 num = get_arg(long long);
3078 break;
3079 case FORMAT_TYPE_ULONG:
3080 case FORMAT_TYPE_LONG:
3081 num = get_arg(unsigned long);
3082 break;
3083 case FORMAT_TYPE_SIZE_T:
3084 num = get_arg(size_t);
3085 break;
3086 case FORMAT_TYPE_PTRDIFF:
3087 num = get_arg(ptrdiff_t);
3088 break;
3089 case FORMAT_TYPE_UBYTE:
3090 num = get_arg(unsigned char);
3091 break;
3092 case FORMAT_TYPE_BYTE:
3093 num = get_arg(signed char);
3094 break;
3095 case FORMAT_TYPE_USHORT:
3096 num = get_arg(unsigned short);
3097 break;
3098 case FORMAT_TYPE_SHORT:
3099 num = get_arg(short);
3100 break;
3101 case FORMAT_TYPE_UINT:
3102 num = get_arg(unsigned int);
3103 break;
3104 default:
3105 num = get_arg(int);
3106 }
3107
3108 str = number(str, end, num, spec);
3109 } /* default: */
3110 } /* switch(spec.type) */
3111 } /* while(*fmt) */
3112
3113 out:
3114 if (size > 0) {
3115 if (str < end)
3116 *str = '\0';
3117 else
3118 end[-1] = '\0';
3119 }
3120
3121 #undef get_arg
3122
3123 /* the trailing null byte doesn't count towards the total */
3124 return str - buf;
3125 }
3126 EXPORT_SYMBOL_GPL(bstr_printf);
3127
3128 /**
3129 * bprintf - Parse a format string and place args' binary value in a buffer
3130 * @bin_buf: The buffer to place args' binary value
3131 * @size: The size of the buffer(by words(32bits), not characters)
3132 * @fmt: The format string to use
3133 * @...: Arguments for the format string
3134 *
3135 * The function returns the number of words(u32) written
3136 * into @bin_buf.
3137 */
3138 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
3139 {
3140 va_list args;
3141 int ret;
3142
3143 va_start(args, fmt);
3144 ret = vbin_printf(bin_buf, size, fmt, args);
3145 va_end(args);
3146
3147 return ret;
3148 }
3149 EXPORT_SYMBOL_GPL(bprintf);
3150
3151 #endif /* CONFIG_BINARY_PRINTF */
3152
3153 /**
3154 * vsscanf - Unformat a buffer into a list of arguments
3155 * @buf: input buffer
3156 * @fmt: format of buffer
3157 * @args: arguments
3158 */
3159 int vsscanf(const char *buf, const char *fmt, va_list args)
3160 {
3161 const char *str = buf;
3162 char *next;
3163 char digit;
3164 int num = 0;
3165 u8 qualifier;
3166 unsigned int base;
3167 union {
3168 long long s;
3169 unsigned long long u;
3170 } val;
3171 s16 field_width;
3172 bool is_sign;
3173
3174 while (*fmt) {
3175 /* skip any white space in format */
3176 /* white space in format matchs any amount of
3177 * white space, including none, in the input.
3178 */
3179 if (isspace(*fmt)) {
3180 fmt = skip_spaces(++fmt);
3181 str = skip_spaces(str);
3182 }
3183
3184 /* anything that is not a conversion must match exactly */
3185 if (*fmt != '%' && *fmt) {
3186 if (*fmt++ != *str++)
3187 break;
3188 continue;
3189 }
3190
3191 if (!*fmt)
3192 break;
3193 ++fmt;
3194
3195 /* skip this conversion.
3196 * advance both strings to next white space
3197 */
3198 if (*fmt == '*') {
3199 if (!*str)
3200 break;
3201 while (!isspace(*fmt) && *fmt != '%' && *fmt) {
3202 /* '%*[' not yet supported, invalid format */
3203 if (*fmt == '[')
3204 return num;
3205 fmt++;
3206 }
3207 while (!isspace(*str) && *str)
3208 str++;
3209 continue;
3210 }
3211
3212 /* get field width */
3213 field_width = -1;
3214 if (isdigit(*fmt)) {
3215 field_width = skip_atoi(&fmt);
3216 if (field_width <= 0)
3217 break;
3218 }
3219
3220 /* get conversion qualifier */
3221 qualifier = -1;
3222 if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
3223 *fmt == 'z') {
3224 qualifier = *fmt++;
3225 if (unlikely(qualifier == *fmt)) {
3226 if (qualifier == 'h') {
3227 qualifier = 'H';
3228 fmt++;
3229 } else if (qualifier == 'l') {
3230 qualifier = 'L';
3231 fmt++;
3232 }
3233 }
3234 }
3235
3236 if (!*fmt)
3237 break;
3238
3239 if (*fmt == 'n') {
3240 /* return number of characters read so far */
3241 *va_arg(args, int *) = str - buf;
3242 ++fmt;
3243 continue;
3244 }
3245
3246 if (!*str)
3247 break;
3248
3249 base = 10;
3250 is_sign = false;
3251
3252 switch (*fmt++) {
3253 case 'c':
3254 {
3255 char *s = (char *)va_arg(args, char*);
3256 if (field_width == -1)
3257 field_width = 1;
3258 do {
3259 *s++ = *str++;
3260 } while (--field_width > 0 && *str);
3261 num++;
3262 }
3263 continue;
3264 case 's':
3265 {
3266 char *s = (char *)va_arg(args, char *);
3267 if (field_width == -1)
3268 field_width = SHRT_MAX;
3269 /* first, skip leading white space in buffer */
3270 str = skip_spaces(str);
3271
3272 /* now copy until next white space */
3273 while (*str && !isspace(*str) && field_width--)
3274 *s++ = *str++;
3275 *s = '\0';
3276 num++;
3277 }
3278 continue;
3279 /*
3280 * Warning: This implementation of the '[' conversion specifier
3281 * deviates from its glibc counterpart in the following ways:
3282 * (1) It does NOT support ranges i.e. '-' is NOT a special
3283 * character
3284 * (2) It cannot match the closing bracket ']' itself
3285 * (3) A field width is required
3286 * (4) '%*[' (discard matching input) is currently not supported
3287 *
3288 * Example usage:
3289 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3290 * buf1, buf2, buf3);
3291 * if (ret < 3)
3292 * // etc..
3293 */
3294 case '[':
3295 {
3296 char *s = (char *)va_arg(args, char *);
3297 DECLARE_BITMAP(set, 256) = {0};
3298 unsigned int len = 0;
3299 bool negate = (*fmt == '^');
3300
3301 /* field width is required */
3302 if (field_width == -1)
3303 return num;
3304
3305 if (negate)
3306 ++fmt;
3307
3308 for ( ; *fmt && *fmt != ']'; ++fmt, ++len)
3309 set_bit((u8)*fmt, set);
3310
3311 /* no ']' or no character set found */
3312 if (!*fmt || !len)
3313 return num;
3314 ++fmt;
3315
3316 if (negate) {
3317 bitmap_complement(set, set, 256);
3318 /* exclude null '\0' byte */
3319 clear_bit(0, set);
3320 }
3321
3322 /* match must be non-empty */
3323 if (!test_bit((u8)*str, set))
3324 return num;
3325
3326 while (test_bit((u8)*str, set) && field_width--)
3327 *s++ = *str++;
3328 *s = '\0';
3329 ++num;
3330 }
3331 continue;
3332 case 'o':
3333 base = 8;
3334 break;
3335 case 'x':
3336 case 'X':
3337 base = 16;
3338 break;
3339 case 'i':
3340 base = 0;
3341 /* fall through */
3342 case 'd':
3343 is_sign = true;
3344 /* fall through */
3345 case 'u':
3346 break;
3347 case '%':
3348 /* looking for '%' in str */
3349 if (*str++ != '%')
3350 return num;
3351 continue;
3352 default:
3353 /* invalid format; stop here */
3354 return num;
3355 }
3356
3357 /* have some sort of integer conversion.
3358 * first, skip white space in buffer.
3359 */
3360 str = skip_spaces(str);
3361
3362 digit = *str;
3363 if (is_sign && digit == '-')
3364 digit = *(str + 1);
3365
3366 if (!digit
3367 || (base == 16 && !isxdigit(digit))
3368 || (base == 10 && !isdigit(digit))
3369 || (base == 8 && (!isdigit(digit) || digit > '7'))
3370 || (base == 0 && !isdigit(digit)))
3371 break;
3372
3373 if (is_sign)
3374 val.s = qualifier != 'L' ?
3375 simple_strtol(str, &next, base) :
3376 simple_strtoll(str, &next, base);
3377 else
3378 val.u = qualifier != 'L' ?
3379 simple_strtoul(str, &next, base) :
3380 simple_strtoull(str, &next, base);
3381
3382 if (field_width > 0 && next - str > field_width) {
3383 if (base == 0)
3384 _parse_integer_fixup_radix(str, &base);
3385 while (next - str > field_width) {
3386 if (is_sign)
3387 val.s = div_s64(val.s, base);
3388 else
3389 val.u = div_u64(val.u, base);
3390 --next;
3391 }
3392 }
3393
3394 switch (qualifier) {
3395 case 'H': /* that's 'hh' in format */
3396 if (is_sign)
3397 *va_arg(args, signed char *) = val.s;
3398 else
3399 *va_arg(args, unsigned char *) = val.u;
3400 break;
3401 case 'h':
3402 if (is_sign)
3403 *va_arg(args, short *) = val.s;
3404 else
3405 *va_arg(args, unsigned short *) = val.u;
3406 break;
3407 case 'l':
3408 if (is_sign)
3409 *va_arg(args, long *) = val.s;
3410 else
3411 *va_arg(args, unsigned long *) = val.u;
3412 break;
3413 case 'L':
3414 if (is_sign)
3415 *va_arg(args, long long *) = val.s;
3416 else
3417 *va_arg(args, unsigned long long *) = val.u;
3418 break;
3419 case 'z':
3420 *va_arg(args, size_t *) = val.u;
3421 break;
3422 default:
3423 if (is_sign)
3424 *va_arg(args, int *) = val.s;
3425 else
3426 *va_arg(args, unsigned int *) = val.u;
3427 break;
3428 }
3429 num++;
3430
3431 if (!next)
3432 break;
3433 str = next;
3434 }
3435
3436 return num;
3437 }
3438 EXPORT_SYMBOL(vsscanf);
3439
3440 /**
3441 * sscanf - Unformat a buffer into a list of arguments
3442 * @buf: input buffer
3443 * @fmt: formatting of buffer
3444 * @...: resulting arguments
3445 */
3446 int sscanf(const char *buf, const char *fmt, ...)
3447 {
3448 va_list args;
3449 int i;
3450
3451 va_start(args, fmt);
3452 i = vsscanf(buf, fmt, args);
3453 va_end(args);
3454
3455 return i;
3456 }
3457 EXPORT_SYMBOL(sscanf);
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