1 // SPDX-License-Identifier: GPL-2.0-only
5 * Copyright (C) 1991, 1992 Linus Torvalds
8 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
10 * Wirzenius wrote this portably, Torvalds fucked it up :-)
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
21 #include <linux/build_bug.h>
22 #include <linux/clk.h>
23 #include <linux/clk-provider.h>
24 #include <linux/errname.h>
25 #include <linux/module.h> /* for KSYM_SYMBOL_LEN */
26 #include <linux/types.h>
27 #include <linux/string.h>
28 #include <linux/ctype.h>
29 #include <linux/kernel.h>
30 #include <linux/kallsyms.h>
31 #include <linux/math64.h>
32 #include <linux/uaccess.h>
33 #include <linux/ioport.h>
34 #include <linux/dcache.h>
35 #include <linux/cred.h>
36 #include <linux/rtc.h>
37 #include <linux/time.h>
38 #include <linux/uuid.h>
40 #include <net/addrconf.h>
41 #include <linux/siphash.h>
42 #include <linux/compiler.h>
43 #include <linux/property.h>
45 #include <linux/blkdev.h>
48 #include "../mm/internal.h" /* For the trace_print_flags arrays */
50 #include <asm/page.h> /* for PAGE_SIZE */
51 #include <asm/byteorder.h> /* cpu_to_le16 */
53 #include <linux/string_helpers.h>
56 static unsigned long long simple_strntoull(const char *startp
, size_t max_chars
,
57 char **endp
, unsigned int base
)
60 unsigned long long result
= 0ULL;
64 cp
= _parse_integer_fixup_radix(startp
, &base
);
65 prefix_chars
= cp
- startp
;
66 if (prefix_chars
< max_chars
) {
67 rv
= _parse_integer_limit(cp
, base
, &result
, max_chars
- prefix_chars
);
69 cp
+= (rv
& ~KSTRTOX_OVERFLOW
);
71 /* Field too short for prefix + digit, skip over without converting */
72 cp
= startp
+ max_chars
;
82 * simple_strtoull - convert a string to an unsigned long long
83 * @cp: The start of the string
84 * @endp: A pointer to the end of the parsed string will be placed here
85 * @base: The number base to use
87 * This function has caveats. Please use kstrtoull instead.
90 unsigned long long simple_strtoull(const char *cp
, char **endp
, unsigned int base
)
92 return simple_strntoull(cp
, INT_MAX
, endp
, base
);
94 EXPORT_SYMBOL(simple_strtoull
);
97 * simple_strtoul - convert a string to an unsigned long
98 * @cp: The start of the string
99 * @endp: A pointer to the end of the parsed string will be placed here
100 * @base: The number base to use
102 * This function has caveats. Please use kstrtoul instead.
104 unsigned long simple_strtoul(const char *cp
, char **endp
, unsigned int base
)
106 return simple_strtoull(cp
, endp
, base
);
108 EXPORT_SYMBOL(simple_strtoul
);
111 * simple_strtol - convert a string to a signed long
112 * @cp: The start of the string
113 * @endp: A pointer to the end of the parsed string will be placed here
114 * @base: The number base to use
116 * This function has caveats. Please use kstrtol instead.
118 long simple_strtol(const char *cp
, char **endp
, unsigned int base
)
121 return -simple_strtoul(cp
+ 1, endp
, base
);
123 return simple_strtoul(cp
, endp
, base
);
125 EXPORT_SYMBOL(simple_strtol
);
127 static long long simple_strntoll(const char *cp
, size_t max_chars
, char **endp
,
131 * simple_strntoull() safely handles receiving max_chars==0 in the
132 * case cp[0] == '-' && max_chars == 1.
133 * If max_chars == 0 we can drop through and pass it to simple_strntoull()
134 * and the content of *cp is irrelevant.
136 if (*cp
== '-' && max_chars
> 0)
137 return -simple_strntoull(cp
+ 1, max_chars
- 1, endp
, base
);
139 return simple_strntoull(cp
, max_chars
, endp
, base
);
143 * simple_strtoll - convert a string to a signed long long
144 * @cp: The start of the string
145 * @endp: A pointer to the end of the parsed string will be placed here
146 * @base: The number base to use
148 * This function has caveats. Please use kstrtoll instead.
150 long long simple_strtoll(const char *cp
, char **endp
, unsigned int base
)
152 return simple_strntoll(cp
, INT_MAX
, endp
, base
);
154 EXPORT_SYMBOL(simple_strtoll
);
156 static noinline_for_stack
157 int skip_atoi(const char **s
)
162 i
= i
*10 + *((*s
)++) - '0';
163 } while (isdigit(**s
));
169 * Decimal conversion is by far the most typical, and is used for
170 * /proc and /sys data. This directly impacts e.g. top performance
171 * with many processes running. We optimize it for speed by emitting
172 * two characters at a time, using a 200 byte lookup table. This
173 * roughly halves the number of multiplications compared to computing
174 * the digits one at a time. Implementation strongly inspired by the
175 * previous version, which in turn used ideas described at
176 * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission
177 * from the author, Douglas W. Jones).
179 * It turns out there is precisely one 26 bit fixed-point
180 * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32
181 * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual
182 * range happens to be somewhat larger (x <= 1073741898), but that's
183 * irrelevant for our purpose.
185 * For dividing a number in the range [10^4, 10^6-1] by 100, we still
186 * need a 32x32->64 bit multiply, so we simply use the same constant.
188 * For dividing a number in the range [100, 10^4-1] by 100, there are
189 * several options. The simplest is (x * 0x147b) >> 19, which is valid
190 * for all x <= 43698.
193 static const u16 decpair
[100] = {
194 #define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030)
195 _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9),
196 _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19),
197 _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29),
198 _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39),
199 _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49),
200 _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59),
201 _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69),
202 _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79),
203 _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89),
204 _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99),
209 * This will print a single '0' even if r == 0, since we would
210 * immediately jump to out_r where two 0s would be written but only
211 * one of them accounted for in buf. This is needed by ip4_string
212 * below. All other callers pass a non-zero value of r.
214 static noinline_for_stack
215 char *put_dec_trunc8(char *buf
, unsigned r
)
223 /* 100 <= r < 10^8 */
224 q
= (r
* (u64
)0x28f5c29) >> 32;
225 *((u16
*)buf
) = decpair
[r
- 100*q
];
232 /* 100 <= q < 10^6 */
233 r
= (q
* (u64
)0x28f5c29) >> 32;
234 *((u16
*)buf
) = decpair
[q
- 100*r
];
241 /* 100 <= r < 10^4 */
242 q
= (r
* 0x147b) >> 19;
243 *((u16
*)buf
) = decpair
[r
- 100*q
];
250 *((u16
*)buf
) = decpair
[r
];
251 buf
+= r
< 10 ? 1 : 2;
255 #if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64
256 static noinline_for_stack
257 char *put_dec_full8(char *buf
, unsigned r
)
262 q
= (r
* (u64
)0x28f5c29) >> 32;
263 *((u16
*)buf
) = decpair
[r
- 100*q
];
267 r
= (q
* (u64
)0x28f5c29) >> 32;
268 *((u16
*)buf
) = decpair
[q
- 100*r
];
272 q
= (r
* 0x147b) >> 19;
273 *((u16
*)buf
) = decpair
[r
- 100*q
];
277 *((u16
*)buf
) = decpair
[q
];
282 static noinline_for_stack
283 char *put_dec(char *buf
, unsigned long long n
)
285 if (n
>= 100*1000*1000)
286 buf
= put_dec_full8(buf
, do_div(n
, 100*1000*1000));
287 /* 1 <= n <= 1.6e11 */
288 if (n
>= 100*1000*1000)
289 buf
= put_dec_full8(buf
, do_div(n
, 100*1000*1000));
291 return put_dec_trunc8(buf
, n
);
294 #elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64
297 put_dec_full4(char *buf
, unsigned r
)
302 q
= (r
* 0x147b) >> 19;
303 *((u16
*)buf
) = decpair
[r
- 100*q
];
306 *((u16
*)buf
) = decpair
[q
];
310 * Call put_dec_full4 on x % 10000, return x / 10000.
311 * The approximation x/10000 == (x * 0x346DC5D7) >> 43
312 * holds for all x < 1,128,869,999. The largest value this
313 * helper will ever be asked to convert is 1,125,520,955.
314 * (second call in the put_dec code, assuming n is all-ones).
316 static noinline_for_stack
317 unsigned put_dec_helper4(char *buf
, unsigned x
)
319 uint32_t q
= (x
* (uint64_t)0x346DC5D7) >> 43;
321 put_dec_full4(buf
, x
- q
* 10000);
325 /* Based on code by Douglas W. Jones found at
326 * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html#sixtyfour>
327 * (with permission from the author).
328 * Performs no 64-bit division and hence should be fast on 32-bit machines.
331 char *put_dec(char *buf
, unsigned long long n
)
333 uint32_t d3
, d2
, d1
, q
, h
;
335 if (n
< 100*1000*1000)
336 return put_dec_trunc8(buf
, n
);
338 d1
= ((uint32_t)n
>> 16); /* implicit "& 0xffff" */
341 d3
= (h
>> 16); /* implicit "& 0xffff" */
343 /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0
344 = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */
345 q
= 656 * d3
+ 7296 * d2
+ 5536 * d1
+ ((uint32_t)n
& 0xffff);
346 q
= put_dec_helper4(buf
, q
);
348 q
+= 7671 * d3
+ 9496 * d2
+ 6 * d1
;
349 q
= put_dec_helper4(buf
+4, q
);
351 q
+= 4749 * d3
+ 42 * d2
;
352 q
= put_dec_helper4(buf
+8, q
);
357 buf
= put_dec_trunc8(buf
, q
);
358 else while (buf
[-1] == '0')
367 * Convert passed number to decimal string.
368 * Returns the length of string. On buffer overflow, returns 0.
370 * If speed is not important, use snprintf(). It's easy to read the code.
372 int num_to_str(char *buf
, int size
, unsigned long long num
, unsigned int width
)
374 /* put_dec requires 2-byte alignment of the buffer. */
375 char tmp
[sizeof(num
) * 3] __aligned(2);
378 /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */
383 len
= put_dec(tmp
, num
) - tmp
;
386 if (len
> size
|| width
> size
)
391 for (idx
= 0; idx
< width
; idx
++)
397 for (idx
= 0; idx
< len
; ++idx
)
398 buf
[idx
+ width
] = tmp
[len
- idx
- 1];
403 #define SIGN 1 /* unsigned/signed, must be 1 */
404 #define LEFT 2 /* left justified */
405 #define PLUS 4 /* show plus */
406 #define SPACE 8 /* space if plus */
407 #define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */
408 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
409 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
411 static_assert(ZEROPAD
== ('0' - ' '));
412 static_assert(SMALL
== ' ');
415 FORMAT_TYPE_NONE
, /* Just a string part */
417 FORMAT_TYPE_PRECISION
,
421 FORMAT_TYPE_PERCENT_CHAR
,
423 FORMAT_TYPE_LONG_LONG
,
437 unsigned int type
:8; /* format_type enum */
438 signed int field_width
:24; /* width of output field */
439 unsigned int flags
:8; /* flags to number() */
440 unsigned int base
:8; /* number base, 8, 10 or 16 only */
441 signed int precision
:16; /* # of digits/chars */
443 static_assert(sizeof(struct printf_spec
) == 8);
445 #define FIELD_WIDTH_MAX ((1 << 23) - 1)
446 #define PRECISION_MAX ((1 << 15) - 1)
448 static noinline_for_stack
449 char *number(char *buf
, char *end
, unsigned long long num
,
450 struct printf_spec spec
)
452 /* put_dec requires 2-byte alignment of the buffer. */
453 char tmp
[3 * sizeof(num
)] __aligned(2);
456 int need_pfx
= ((spec
.flags
& SPECIAL
) && spec
.base
!= 10);
458 bool is_zero
= num
== 0LL;
459 int field_width
= spec
.field_width
;
460 int precision
= spec
.precision
;
462 /* locase = 0 or 0x20. ORing digits or letters with 'locase'
463 * produces same digits or (maybe lowercased) letters */
464 locase
= (spec
.flags
& SMALL
);
465 if (spec
.flags
& LEFT
)
466 spec
.flags
&= ~ZEROPAD
;
468 if (spec
.flags
& SIGN
) {
469 if ((signed long long)num
< 0) {
471 num
= -(signed long long)num
;
473 } else if (spec
.flags
& PLUS
) {
476 } else if (spec
.flags
& SPACE
) {
488 /* generate full string in tmp[], in reverse order */
491 tmp
[i
++] = hex_asc_upper
[num
] | locase
;
492 else if (spec
.base
!= 10) { /* 8 or 16 */
493 int mask
= spec
.base
- 1;
499 tmp
[i
++] = (hex_asc_upper
[((unsigned char)num
) & mask
] | locase
);
502 } else { /* base 10 */
503 i
= put_dec(tmp
, num
) - tmp
;
506 /* printing 100 using %2d gives "100", not "00" */
509 /* leading space padding */
510 field_width
-= precision
;
511 if (!(spec
.flags
& (ZEROPAD
| LEFT
))) {
512 while (--field_width
>= 0) {
524 /* "0x" / "0" prefix */
526 if (spec
.base
== 16 || !is_zero
) {
531 if (spec
.base
== 16) {
533 *buf
= ('X' | locase
);
537 /* zero or space padding */
538 if (!(spec
.flags
& LEFT
)) {
539 char c
= ' ' + (spec
.flags
& ZEROPAD
);
541 while (--field_width
>= 0) {
547 /* hmm even more zero padding? */
548 while (i
<= --precision
) {
553 /* actual digits of result */
559 /* trailing space padding */
560 while (--field_width
>= 0) {
569 static noinline_for_stack
570 char *special_hex_number(char *buf
, char *end
, unsigned long long num
, int size
)
572 struct printf_spec spec
;
574 spec
.type
= FORMAT_TYPE_PTR
;
575 spec
.field_width
= 2 + 2 * size
; /* 0x + hex */
576 spec
.flags
= SPECIAL
| SMALL
| ZEROPAD
;
580 return number(buf
, end
, num
, spec
);
583 static void move_right(char *buf
, char *end
, unsigned len
, unsigned spaces
)
586 if (buf
>= end
) /* nowhere to put anything */
589 if (size
<= spaces
) {
590 memset(buf
, ' ', size
);
594 if (len
> size
- spaces
)
596 memmove(buf
+ spaces
, buf
, len
);
598 memset(buf
, ' ', spaces
);
602 * Handle field width padding for a string.
603 * @buf: current buffer position
604 * @n: length of string
605 * @end: end of output buffer
606 * @spec: for field width and flags
607 * Returns: new buffer position after padding.
609 static noinline_for_stack
610 char *widen_string(char *buf
, int n
, char *end
, struct printf_spec spec
)
614 if (likely(n
>= spec
.field_width
))
616 /* we want to pad the sucker */
617 spaces
= spec
.field_width
- n
;
618 if (!(spec
.flags
& LEFT
)) {
619 move_right(buf
- n
, end
, n
, spaces
);
630 /* Handle string from a well known address. */
631 static char *string_nocheck(char *buf
, char *end
, const char *s
,
632 struct printf_spec spec
)
635 int lim
= spec
.precision
;
646 return widen_string(buf
, len
, end
, spec
);
649 static char *err_ptr(char *buf
, char *end
, void *ptr
,
650 struct printf_spec spec
)
652 int err
= PTR_ERR(ptr
);
653 const char *sym
= errname(err
);
656 return string_nocheck(buf
, end
, sym
, spec
);
659 * Somebody passed ERR_PTR(-1234) or some other non-existing
660 * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to
661 * printing it as its decimal representation.
665 return number(buf
, end
, err
, spec
);
668 /* Be careful: error messages must fit into the given buffer. */
669 static char *error_string(char *buf
, char *end
, const char *s
,
670 struct printf_spec spec
)
673 * Hard limit to avoid a completely insane messages. It actually
674 * works pretty well because most error messages are in
675 * the many pointer format modifiers.
677 if (spec
.precision
== -1)
678 spec
.precision
= 2 * sizeof(void *);
680 return string_nocheck(buf
, end
, s
, spec
);
684 * Do not call any complex external code here. Nested printk()/vsprintf()
685 * might cause infinite loops. Failures might break printk() and would
688 static const char *check_pointer_msg(const void *ptr
)
693 if ((unsigned long)ptr
< PAGE_SIZE
|| IS_ERR_VALUE(ptr
))
699 static int check_pointer(char **buf
, char *end
, const void *ptr
,
700 struct printf_spec spec
)
704 err_msg
= check_pointer_msg(ptr
);
706 *buf
= error_string(*buf
, end
, err_msg
, spec
);
713 static noinline_for_stack
714 char *string(char *buf
, char *end
, const char *s
,
715 struct printf_spec spec
)
717 if (check_pointer(&buf
, end
, s
, spec
))
720 return string_nocheck(buf
, end
, s
, spec
);
723 static char *pointer_string(char *buf
, char *end
,
725 struct printf_spec spec
)
729 if (spec
.field_width
== -1) {
730 spec
.field_width
= 2 * sizeof(ptr
);
731 spec
.flags
|= ZEROPAD
;
734 return number(buf
, end
, (unsigned long int)ptr
, spec
);
737 /* Make pointers available for printing early in the boot sequence. */
738 static int debug_boot_weak_hash __ro_after_init
;
740 static int __init
debug_boot_weak_hash_enable(char *str
)
742 debug_boot_weak_hash
= 1;
743 pr_info("debug_boot_weak_hash enabled\n");
746 early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable
);
748 static DEFINE_STATIC_KEY_TRUE(not_filled_random_ptr_key
);
749 static siphash_key_t ptr_key __read_mostly
;
751 static void enable_ptr_key_workfn(struct work_struct
*work
)
753 get_random_bytes(&ptr_key
, sizeof(ptr_key
));
754 /* Needs to run from preemptible context */
755 static_branch_disable(¬_filled_random_ptr_key
);
758 static DECLARE_WORK(enable_ptr_key_work
, enable_ptr_key_workfn
);
760 static void fill_random_ptr_key(struct random_ready_callback
*unused
)
762 /* This may be in an interrupt handler. */
763 queue_work(system_unbound_wq
, &enable_ptr_key_work
);
766 static struct random_ready_callback random_ready
= {
767 .func
= fill_random_ptr_key
770 static int __init
initialize_ptr_random(void)
772 int key_size
= sizeof(ptr_key
);
775 /* Use hw RNG if available. */
776 if (get_random_bytes_arch(&ptr_key
, key_size
) == key_size
) {
777 static_branch_disable(¬_filled_random_ptr_key
);
781 ret
= add_random_ready_callback(&random_ready
);
784 } else if (ret
== -EALREADY
) {
785 /* This is in preemptible context */
786 enable_ptr_key_workfn(&enable_ptr_key_work
);
792 early_initcall(initialize_ptr_random
);
794 /* Maps a pointer to a 32 bit unique identifier. */
795 static inline int __ptr_to_hashval(const void *ptr
, unsigned long *hashval_out
)
797 unsigned long hashval
;
799 if (static_branch_unlikely(¬_filled_random_ptr_key
))
803 hashval
= (unsigned long)siphash_1u64((u64
)ptr
, &ptr_key
);
805 * Mask off the first 32 bits, this makes explicit that we have
806 * modified the address (and 32 bits is plenty for a unique ID).
808 hashval
= hashval
& 0xffffffff;
810 hashval
= (unsigned long)siphash_1u32((u32
)ptr
, &ptr_key
);
812 *hashval_out
= hashval
;
816 int ptr_to_hashval(const void *ptr
, unsigned long *hashval_out
)
818 return __ptr_to_hashval(ptr
, hashval_out
);
821 static char *ptr_to_id(char *buf
, char *end
, const void *ptr
,
822 struct printf_spec spec
)
824 const char *str
= sizeof(ptr
) == 8 ? "(____ptrval____)" : "(ptrval)";
825 unsigned long hashval
;
829 * Print the real pointer value for NULL and error pointers,
830 * as they are not actual addresses.
832 if (IS_ERR_OR_NULL(ptr
))
833 return pointer_string(buf
, end
, ptr
, spec
);
835 /* When debugging early boot use non-cryptographically secure hash. */
836 if (unlikely(debug_boot_weak_hash
)) {
837 hashval
= hash_long((unsigned long)ptr
, 32);
838 return pointer_string(buf
, end
, (const void *)hashval
, spec
);
841 ret
= __ptr_to_hashval(ptr
, &hashval
);
843 spec
.field_width
= 2 * sizeof(ptr
);
844 /* string length must be less than default_width */
845 return error_string(buf
, end
, str
, spec
);
848 return pointer_string(buf
, end
, (const void *)hashval
, spec
);
851 int kptr_restrict __read_mostly
;
853 static noinline_for_stack
854 char *restricted_pointer(char *buf
, char *end
, const void *ptr
,
855 struct printf_spec spec
)
857 switch (kptr_restrict
) {
859 /* Handle as %p, hash and do _not_ leak addresses. */
860 return ptr_to_id(buf
, end
, ptr
, spec
);
862 const struct cred
*cred
;
865 * kptr_restrict==1 cannot be used in IRQ context
866 * because its test for CAP_SYSLOG would be meaningless.
868 if (in_irq() || in_serving_softirq() || in_nmi()) {
869 if (spec
.field_width
== -1)
870 spec
.field_width
= 2 * sizeof(ptr
);
871 return error_string(buf
, end
, "pK-error", spec
);
875 * Only print the real pointer value if the current
876 * process has CAP_SYSLOG and is running with the
877 * same credentials it started with. This is because
878 * access to files is checked at open() time, but %pK
879 * checks permission at read() time. We don't want to
880 * leak pointer values if a binary opens a file using
881 * %pK and then elevates privileges before reading it.
883 cred
= current_cred();
884 if (!has_capability_noaudit(current
, CAP_SYSLOG
) ||
885 !uid_eq(cred
->euid
, cred
->uid
) ||
886 !gid_eq(cred
->egid
, cred
->gid
))
892 /* Always print 0's for %pK */
897 return pointer_string(buf
, end
, ptr
, spec
);
900 static noinline_for_stack
901 char *dentry_name(char *buf
, char *end
, const struct dentry
*d
, struct printf_spec spec
,
904 const char *array
[4], *s
;
905 const struct dentry
*p
;
910 case '2': case '3': case '4':
911 depth
= fmt
[1] - '0';
918 for (i
= 0; i
< depth
; i
++, d
= p
) {
919 if (check_pointer(&buf
, end
, d
, spec
)) {
924 p
= READ_ONCE(d
->d_parent
);
925 array
[i
] = READ_ONCE(d
->d_name
.name
);
934 for (n
= 0; n
!= spec
.precision
; n
++, buf
++) {
946 return widen_string(buf
, n
, end
, spec
);
949 static noinline_for_stack
950 char *file_dentry_name(char *buf
, char *end
, const struct file
*f
,
951 struct printf_spec spec
, const char *fmt
)
953 if (check_pointer(&buf
, end
, f
, spec
))
956 return dentry_name(buf
, end
, f
->f_path
.dentry
, spec
, fmt
);
959 static noinline_for_stack
960 char *bdev_name(char *buf
, char *end
, struct block_device
*bdev
,
961 struct printf_spec spec
, const char *fmt
)
965 if (check_pointer(&buf
, end
, bdev
, spec
))
969 buf
= string(buf
, end
, hd
->disk_name
, spec
);
970 if (bdev
->bd_partno
) {
971 if (isdigit(hd
->disk_name
[strlen(hd
->disk_name
)-1])) {
976 buf
= number(buf
, end
, bdev
->bd_partno
, spec
);
982 static noinline_for_stack
983 char *symbol_string(char *buf
, char *end
, void *ptr
,
984 struct printf_spec spec
, const char *fmt
)
987 #ifdef CONFIG_KALLSYMS
988 char sym
[KSYM_SYMBOL_LEN
];
992 ptr
= __builtin_extract_return_addr(ptr
);
993 value
= (unsigned long)ptr
;
995 #ifdef CONFIG_KALLSYMS
996 if (*fmt
== 'B' && fmt
[1] == 'b')
997 sprint_backtrace_build_id(sym
, value
);
998 else if (*fmt
== 'B')
999 sprint_backtrace(sym
, value
);
1000 else if (*fmt
== 'S' && (fmt
[1] == 'b' || (fmt
[1] == 'R' && fmt
[2] == 'b')))
1001 sprint_symbol_build_id(sym
, value
);
1002 else if (*fmt
!= 's')
1003 sprint_symbol(sym
, value
);
1005 sprint_symbol_no_offset(sym
, value
);
1007 return string_nocheck(buf
, end
, sym
, spec
);
1009 return special_hex_number(buf
, end
, value
, sizeof(void *));
1013 static const struct printf_spec default_str_spec
= {
1018 static const struct printf_spec default_flag_spec
= {
1021 .flags
= SPECIAL
| SMALL
,
1024 static const struct printf_spec default_dec_spec
= {
1029 static const struct printf_spec default_dec02_spec
= {
1036 static const struct printf_spec default_dec04_spec
= {
1043 static noinline_for_stack
1044 char *resource_string(char *buf
, char *end
, struct resource
*res
,
1045 struct printf_spec spec
, const char *fmt
)
1047 #ifndef IO_RSRC_PRINTK_SIZE
1048 #define IO_RSRC_PRINTK_SIZE 6
1051 #ifndef MEM_RSRC_PRINTK_SIZE
1052 #define MEM_RSRC_PRINTK_SIZE 10
1054 static const struct printf_spec io_spec
= {
1056 .field_width
= IO_RSRC_PRINTK_SIZE
,
1058 .flags
= SPECIAL
| SMALL
| ZEROPAD
,
1060 static const struct printf_spec mem_spec
= {
1062 .field_width
= MEM_RSRC_PRINTK_SIZE
,
1064 .flags
= SPECIAL
| SMALL
| ZEROPAD
,
1066 static const struct printf_spec bus_spec
= {
1070 .flags
= SMALL
| ZEROPAD
,
1072 static const struct printf_spec str_spec
= {
1078 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
1079 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
1080 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
1081 #define FLAG_BUF_SIZE (2 * sizeof(res->flags))
1082 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
1083 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
1084 char sym
[max(2*RSRC_BUF_SIZE
+ DECODED_BUF_SIZE
,
1085 2*RSRC_BUF_SIZE
+ FLAG_BUF_SIZE
+ RAW_BUF_SIZE
)];
1087 char *p
= sym
, *pend
= sym
+ sizeof(sym
);
1088 int decode
= (fmt
[0] == 'R') ? 1 : 0;
1089 const struct printf_spec
*specp
;
1091 if (check_pointer(&buf
, end
, res
, spec
))
1095 if (res
->flags
& IORESOURCE_IO
) {
1096 p
= string_nocheck(p
, pend
, "io ", str_spec
);
1098 } else if (res
->flags
& IORESOURCE_MEM
) {
1099 p
= string_nocheck(p
, pend
, "mem ", str_spec
);
1101 } else if (res
->flags
& IORESOURCE_IRQ
) {
1102 p
= string_nocheck(p
, pend
, "irq ", str_spec
);
1103 specp
= &default_dec_spec
;
1104 } else if (res
->flags
& IORESOURCE_DMA
) {
1105 p
= string_nocheck(p
, pend
, "dma ", str_spec
);
1106 specp
= &default_dec_spec
;
1107 } else if (res
->flags
& IORESOURCE_BUS
) {
1108 p
= string_nocheck(p
, pend
, "bus ", str_spec
);
1111 p
= string_nocheck(p
, pend
, "??? ", str_spec
);
1115 if (decode
&& res
->flags
& IORESOURCE_UNSET
) {
1116 p
= string_nocheck(p
, pend
, "size ", str_spec
);
1117 p
= number(p
, pend
, resource_size(res
), *specp
);
1119 p
= number(p
, pend
, res
->start
, *specp
);
1120 if (res
->start
!= res
->end
) {
1122 p
= number(p
, pend
, res
->end
, *specp
);
1126 if (res
->flags
& IORESOURCE_MEM_64
)
1127 p
= string_nocheck(p
, pend
, " 64bit", str_spec
);
1128 if (res
->flags
& IORESOURCE_PREFETCH
)
1129 p
= string_nocheck(p
, pend
, " pref", str_spec
);
1130 if (res
->flags
& IORESOURCE_WINDOW
)
1131 p
= string_nocheck(p
, pend
, " window", str_spec
);
1132 if (res
->flags
& IORESOURCE_DISABLED
)
1133 p
= string_nocheck(p
, pend
, " disabled", str_spec
);
1135 p
= string_nocheck(p
, pend
, " flags ", str_spec
);
1136 p
= number(p
, pend
, res
->flags
, default_flag_spec
);
1141 return string_nocheck(buf
, end
, sym
, spec
);
1144 static noinline_for_stack
1145 char *hex_string(char *buf
, char *end
, u8
*addr
, struct printf_spec spec
,
1148 int i
, len
= 1; /* if we pass '%ph[CDN]', field width remains
1149 negative value, fallback to the default */
1152 if (spec
.field_width
== 0)
1153 /* nothing to print */
1156 if (check_pointer(&buf
, end
, addr
, spec
))
1174 if (spec
.field_width
> 0)
1175 len
= min_t(int, spec
.field_width
, 64);
1177 for (i
= 0; i
< len
; ++i
) {
1179 *buf
= hex_asc_hi(addr
[i
]);
1182 *buf
= hex_asc_lo(addr
[i
]);
1185 if (separator
&& i
!= len
- 1) {
1195 static noinline_for_stack
1196 char *bitmap_string(char *buf
, char *end
, unsigned long *bitmap
,
1197 struct printf_spec spec
, const char *fmt
)
1199 const int CHUNKSZ
= 32;
1200 int nr_bits
= max_t(int, spec
.field_width
, 0);
1204 if (check_pointer(&buf
, end
, bitmap
, spec
))
1207 /* reused to print numbers */
1208 spec
= (struct printf_spec
){ .flags
= SMALL
| ZEROPAD
, .base
= 16 };
1210 chunksz
= nr_bits
& (CHUNKSZ
- 1);
1214 i
= ALIGN(nr_bits
, CHUNKSZ
) - CHUNKSZ
;
1215 for (; i
>= 0; i
-= CHUNKSZ
) {
1219 chunkmask
= ((1ULL << chunksz
) - 1);
1220 word
= i
/ BITS_PER_LONG
;
1221 bit
= i
% BITS_PER_LONG
;
1222 val
= (bitmap
[word
] >> bit
) & chunkmask
;
1231 spec
.field_width
= DIV_ROUND_UP(chunksz
, 4);
1232 buf
= number(buf
, end
, val
, spec
);
1239 static noinline_for_stack
1240 char *bitmap_list_string(char *buf
, char *end
, unsigned long *bitmap
,
1241 struct printf_spec spec
, const char *fmt
)
1243 int nr_bits
= max_t(int, spec
.field_width
, 0);
1244 /* current bit is 'cur', most recently seen range is [rbot, rtop] */
1245 int cur
, rbot
, rtop
;
1248 if (check_pointer(&buf
, end
, bitmap
, spec
))
1251 rbot
= cur
= find_first_bit(bitmap
, nr_bits
);
1252 while (cur
< nr_bits
) {
1254 cur
= find_next_bit(bitmap
, nr_bits
, cur
+ 1);
1255 if (cur
< nr_bits
&& cur
<= rtop
+ 1)
1265 buf
= number(buf
, end
, rbot
, default_dec_spec
);
1271 buf
= number(buf
, end
, rtop
, default_dec_spec
);
1279 static noinline_for_stack
1280 char *mac_address_string(char *buf
, char *end
, u8
*addr
,
1281 struct printf_spec spec
, const char *fmt
)
1283 char mac_addr
[sizeof("xx:xx:xx:xx:xx:xx")];
1287 bool reversed
= false;
1289 if (check_pointer(&buf
, end
, addr
, spec
))
1306 for (i
= 0; i
< 6; i
++) {
1308 p
= hex_byte_pack(p
, addr
[5 - i
]);
1310 p
= hex_byte_pack(p
, addr
[i
]);
1312 if (fmt
[0] == 'M' && i
!= 5)
1317 return string_nocheck(buf
, end
, mac_addr
, spec
);
1320 static noinline_for_stack
1321 char *ip4_string(char *p
, const u8
*addr
, const char *fmt
)
1324 bool leading_zeros
= (fmt
[0] == 'i');
1349 for (i
= 0; i
< 4; i
++) {
1350 char temp
[4] __aligned(2); /* hold each IP quad in reverse order */
1351 int digits
= put_dec_trunc8(temp
, addr
[index
]) - temp
;
1352 if (leading_zeros
) {
1358 /* reverse the digits in the quad */
1360 *p
++ = temp
[digits
];
1370 static noinline_for_stack
1371 char *ip6_compressed_string(char *p
, const char *addr
)
1374 unsigned char zerolength
[8];
1379 bool needcolon
= false;
1381 struct in6_addr in6
;
1383 memcpy(&in6
, addr
, sizeof(struct in6_addr
));
1385 useIPv4
= ipv6_addr_v4mapped(&in6
) || ipv6_addr_is_isatap(&in6
);
1387 memset(zerolength
, 0, sizeof(zerolength
));
1394 /* find position of longest 0 run */
1395 for (i
= 0; i
< range
; i
++) {
1396 for (j
= i
; j
< range
; j
++) {
1397 if (in6
.s6_addr16
[j
] != 0)
1402 for (i
= 0; i
< range
; i
++) {
1403 if (zerolength
[i
] > longest
) {
1404 longest
= zerolength
[i
];
1408 if (longest
== 1) /* don't compress a single 0 */
1412 for (i
= 0; i
< range
; i
++) {
1413 if (i
== colonpos
) {
1414 if (needcolon
|| i
== 0)
1425 /* hex u16 without leading 0s */
1426 word
= ntohs(in6
.s6_addr16
[i
]);
1431 p
= hex_byte_pack(p
, hi
);
1433 *p
++ = hex_asc_lo(hi
);
1434 p
= hex_byte_pack(p
, lo
);
1437 p
= hex_byte_pack(p
, lo
);
1439 *p
++ = hex_asc_lo(lo
);
1446 p
= ip4_string(p
, &in6
.s6_addr
[12], "I4");
1453 static noinline_for_stack
1454 char *ip6_string(char *p
, const char *addr
, const char *fmt
)
1458 for (i
= 0; i
< 8; i
++) {
1459 p
= hex_byte_pack(p
, *addr
++);
1460 p
= hex_byte_pack(p
, *addr
++);
1461 if (fmt
[0] == 'I' && i
!= 7)
1469 static noinline_for_stack
1470 char *ip6_addr_string(char *buf
, char *end
, const u8
*addr
,
1471 struct printf_spec spec
, const char *fmt
)
1473 char ip6_addr
[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
1475 if (fmt
[0] == 'I' && fmt
[2] == 'c')
1476 ip6_compressed_string(ip6_addr
, addr
);
1478 ip6_string(ip6_addr
, addr
, fmt
);
1480 return string_nocheck(buf
, end
, ip6_addr
, spec
);
1483 static noinline_for_stack
1484 char *ip4_addr_string(char *buf
, char *end
, const u8
*addr
,
1485 struct printf_spec spec
, const char *fmt
)
1487 char ip4_addr
[sizeof("255.255.255.255")];
1489 ip4_string(ip4_addr
, addr
, fmt
);
1491 return string_nocheck(buf
, end
, ip4_addr
, spec
);
1494 static noinline_for_stack
1495 char *ip6_addr_string_sa(char *buf
, char *end
, const struct sockaddr_in6
*sa
,
1496 struct printf_spec spec
, const char *fmt
)
1498 bool have_p
= false, have_s
= false, have_f
= false, have_c
= false;
1499 char ip6_addr
[sizeof("[xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255]") +
1500 sizeof(":12345") + sizeof("/123456789") +
1501 sizeof("%1234567890")];
1502 char *p
= ip6_addr
, *pend
= ip6_addr
+ sizeof(ip6_addr
);
1503 const u8
*addr
= (const u8
*) &sa
->sin6_addr
;
1504 char fmt6
[2] = { fmt
[0], '6' };
1508 while (isalpha(*++fmt
)) {
1525 if (have_p
|| have_s
|| have_f
) {
1530 if (fmt6
[0] == 'I' && have_c
)
1531 p
= ip6_compressed_string(ip6_addr
+ off
, addr
);
1533 p
= ip6_string(ip6_addr
+ off
, addr
, fmt6
);
1535 if (have_p
|| have_s
|| have_f
)
1540 p
= number(p
, pend
, ntohs(sa
->sin6_port
), spec
);
1544 p
= number(p
, pend
, ntohl(sa
->sin6_flowinfo
&
1545 IPV6_FLOWINFO_MASK
), spec
);
1549 p
= number(p
, pend
, sa
->sin6_scope_id
, spec
);
1553 return string_nocheck(buf
, end
, ip6_addr
, spec
);
1556 static noinline_for_stack
1557 char *ip4_addr_string_sa(char *buf
, char *end
, const struct sockaddr_in
*sa
,
1558 struct printf_spec spec
, const char *fmt
)
1560 bool have_p
= false;
1561 char *p
, ip4_addr
[sizeof("255.255.255.255") + sizeof(":12345")];
1562 char *pend
= ip4_addr
+ sizeof(ip4_addr
);
1563 const u8
*addr
= (const u8
*) &sa
->sin_addr
.s_addr
;
1564 char fmt4
[3] = { fmt
[0], '4', 0 };
1567 while (isalpha(*++fmt
)) {
1581 p
= ip4_string(ip4_addr
, addr
, fmt4
);
1584 p
= number(p
, pend
, ntohs(sa
->sin_port
), spec
);
1588 return string_nocheck(buf
, end
, ip4_addr
, spec
);
1591 static noinline_for_stack
1592 char *ip_addr_string(char *buf
, char *end
, const void *ptr
,
1593 struct printf_spec spec
, const char *fmt
)
1597 if (check_pointer(&buf
, end
, ptr
, spec
))
1602 return ip6_addr_string(buf
, end
, ptr
, spec
, fmt
);
1604 return ip4_addr_string(buf
, end
, ptr
, spec
, fmt
);
1607 struct sockaddr raw
;
1608 struct sockaddr_in v4
;
1609 struct sockaddr_in6 v6
;
1612 switch (sa
->raw
.sa_family
) {
1614 return ip4_addr_string_sa(buf
, end
, &sa
->v4
, spec
, fmt
);
1616 return ip6_addr_string_sa(buf
, end
, &sa
->v6
, spec
, fmt
);
1618 return error_string(buf
, end
, "(einval)", spec
);
1622 err_fmt_msg
= fmt
[0] == 'i' ? "(%pi?)" : "(%pI?)";
1623 return error_string(buf
, end
, err_fmt_msg
, spec
);
1626 static noinline_for_stack
1627 char *escaped_string(char *buf
, char *end
, u8
*addr
, struct printf_spec spec
,
1632 unsigned int flags
= 0;
1635 if (spec
.field_width
== 0)
1636 return buf
; /* nothing to print */
1638 if (check_pointer(&buf
, end
, addr
, spec
))
1642 switch (fmt
[count
++]) {
1644 flags
|= ESCAPE_ANY
;
1647 flags
|= ESCAPE_SPECIAL
;
1650 flags
|= ESCAPE_HEX
;
1653 flags
|= ESCAPE_NULL
;
1656 flags
|= ESCAPE_OCTAL
;
1662 flags
|= ESCAPE_SPACE
;
1671 flags
= ESCAPE_ANY_NP
;
1673 len
= spec
.field_width
< 0 ? 1 : spec
.field_width
;
1676 * string_escape_mem() writes as many characters as it can to
1677 * the given buffer, and returns the total size of the output
1678 * had the buffer been big enough.
1680 buf
+= string_escape_mem(addr
, len
, buf
, buf
< end
? end
- buf
: 0, flags
, NULL
);
1685 static char *va_format(char *buf
, char *end
, struct va_format
*va_fmt
,
1686 struct printf_spec spec
, const char *fmt
)
1690 if (check_pointer(&buf
, end
, va_fmt
, spec
))
1693 va_copy(va
, *va_fmt
->va
);
1694 buf
+= vsnprintf(buf
, end
> buf
? end
- buf
: 0, va_fmt
->fmt
, va
);
1700 static noinline_for_stack
1701 char *uuid_string(char *buf
, char *end
, const u8
*addr
,
1702 struct printf_spec spec
, const char *fmt
)
1704 char uuid
[UUID_STRING_LEN
+ 1];
1707 const u8
*index
= uuid_index
;
1710 if (check_pointer(&buf
, end
, addr
, spec
))
1725 for (i
= 0; i
< 16; i
++) {
1727 p
= hex_byte_pack_upper(p
, addr
[index
[i
]]);
1729 p
= hex_byte_pack(p
, addr
[index
[i
]]);
1742 return string_nocheck(buf
, end
, uuid
, spec
);
1745 static noinline_for_stack
1746 char *netdev_bits(char *buf
, char *end
, const void *addr
,
1747 struct printf_spec spec
, const char *fmt
)
1749 unsigned long long num
;
1752 if (check_pointer(&buf
, end
, addr
, spec
))
1757 num
= *(const netdev_features_t
*)addr
;
1758 size
= sizeof(netdev_features_t
);
1761 return error_string(buf
, end
, "(%pN?)", spec
);
1764 return special_hex_number(buf
, end
, num
, size
);
1767 static noinline_for_stack
1768 char *fourcc_string(char *buf
, char *end
, const u32
*fourcc
,
1769 struct printf_spec spec
, const char *fmt
)
1771 char output
[sizeof("0123 little-endian (0x01234567)")];
1776 if (fmt
[1] != 'c' || fmt
[2] != 'c')
1777 return error_string(buf
, end
, "(%p4?)", spec
);
1779 if (check_pointer(&buf
, end
, fourcc
, spec
))
1782 val
= *fourcc
& ~BIT(31);
1784 for (i
= 0; i
< sizeof(*fourcc
); i
++) {
1785 unsigned char c
= val
>> (i
* 8);
1787 /* Print non-control ASCII characters as-is, dot otherwise */
1788 *p
++ = isascii(c
) && isprint(c
) ? c
: '.';
1791 strcpy(p
, *fourcc
& BIT(31) ? " big-endian" : " little-endian");
1796 p
= special_hex_number(p
, output
+ sizeof(output
) - 2, *fourcc
, sizeof(u32
));
1800 return string(buf
, end
, output
, spec
);
1803 static noinline_for_stack
1804 char *address_val(char *buf
, char *end
, const void *addr
,
1805 struct printf_spec spec
, const char *fmt
)
1807 unsigned long long num
;
1810 if (check_pointer(&buf
, end
, addr
, spec
))
1815 num
= *(const dma_addr_t
*)addr
;
1816 size
= sizeof(dma_addr_t
);
1820 num
= *(const phys_addr_t
*)addr
;
1821 size
= sizeof(phys_addr_t
);
1825 return special_hex_number(buf
, end
, num
, size
);
1828 static noinline_for_stack
1829 char *date_str(char *buf
, char *end
, const struct rtc_time
*tm
, bool r
)
1831 int year
= tm
->tm_year
+ (r
? 0 : 1900);
1832 int mon
= tm
->tm_mon
+ (r
? 0 : 1);
1834 buf
= number(buf
, end
, year
, default_dec04_spec
);
1839 buf
= number(buf
, end
, mon
, default_dec02_spec
);
1844 return number(buf
, end
, tm
->tm_mday
, default_dec02_spec
);
1847 static noinline_for_stack
1848 char *time_str(char *buf
, char *end
, const struct rtc_time
*tm
, bool r
)
1850 buf
= number(buf
, end
, tm
->tm_hour
, default_dec02_spec
);
1855 buf
= number(buf
, end
, tm
->tm_min
, default_dec02_spec
);
1860 return number(buf
, end
, tm
->tm_sec
, default_dec02_spec
);
1863 static noinline_for_stack
1864 char *rtc_str(char *buf
, char *end
, const struct rtc_time
*tm
,
1865 struct printf_spec spec
, const char *fmt
)
1867 bool have_t
= true, have_d
= true;
1868 bool raw
= false, iso8601_separator
= true;
1872 if (check_pointer(&buf
, end
, tm
, spec
))
1875 switch (fmt
[count
]) {
1887 switch (fmt
[count
++]) {
1892 iso8601_separator
= false;
1901 buf
= date_str(buf
, end
, tm
, raw
);
1902 if (have_d
&& have_t
) {
1904 *buf
= iso8601_separator
? 'T' : ' ';
1908 buf
= time_str(buf
, end
, tm
, raw
);
1913 static noinline_for_stack
1914 char *time64_str(char *buf
, char *end
, const time64_t time
,
1915 struct printf_spec spec
, const char *fmt
)
1917 struct rtc_time rtc_time
;
1920 time64_to_tm(time
, 0, &tm
);
1922 rtc_time
.tm_sec
= tm
.tm_sec
;
1923 rtc_time
.tm_min
= tm
.tm_min
;
1924 rtc_time
.tm_hour
= tm
.tm_hour
;
1925 rtc_time
.tm_mday
= tm
.tm_mday
;
1926 rtc_time
.tm_mon
= tm
.tm_mon
;
1927 rtc_time
.tm_year
= tm
.tm_year
;
1928 rtc_time
.tm_wday
= tm
.tm_wday
;
1929 rtc_time
.tm_yday
= tm
.tm_yday
;
1931 rtc_time
.tm_isdst
= 0;
1933 return rtc_str(buf
, end
, &rtc_time
, spec
, fmt
);
1936 static noinline_for_stack
1937 char *time_and_date(char *buf
, char *end
, void *ptr
, struct printf_spec spec
,
1942 return rtc_str(buf
, end
, (const struct rtc_time
*)ptr
, spec
, fmt
);
1944 return time64_str(buf
, end
, *(const time64_t
*)ptr
, spec
, fmt
);
1946 return error_string(buf
, end
, "(%pt?)", spec
);
1950 static noinline_for_stack
1951 char *clock(char *buf
, char *end
, struct clk
*clk
, struct printf_spec spec
,
1954 if (!IS_ENABLED(CONFIG_HAVE_CLK
))
1955 return error_string(buf
, end
, "(%pC?)", spec
);
1957 if (check_pointer(&buf
, end
, clk
, spec
))
1963 #ifdef CONFIG_COMMON_CLK
1964 return string(buf
, end
, __clk_get_name(clk
), spec
);
1966 return ptr_to_id(buf
, end
, clk
, spec
);
1972 char *format_flags(char *buf
, char *end
, unsigned long flags
,
1973 const struct trace_print_flags
*names
)
1977 for ( ; flags
&& names
->name
; names
++) {
1979 if ((flags
& mask
) != mask
)
1982 buf
= string(buf
, end
, names
->name
, default_str_spec
);
1993 buf
= number(buf
, end
, flags
, default_flag_spec
);
1998 struct page_flags_fields
{
2002 const struct printf_spec
*spec
;
2006 static const struct page_flags_fields pff
[] = {
2007 {SECTIONS_WIDTH
, SECTIONS_PGSHIFT
, SECTIONS_MASK
,
2008 &default_dec_spec
, "section"},
2009 {NODES_WIDTH
, NODES_PGSHIFT
, NODES_MASK
,
2010 &default_dec_spec
, "node"},
2011 {ZONES_WIDTH
, ZONES_PGSHIFT
, ZONES_MASK
,
2012 &default_dec_spec
, "zone"},
2013 {LAST_CPUPID_WIDTH
, LAST_CPUPID_PGSHIFT
, LAST_CPUPID_MASK
,
2014 &default_flag_spec
, "lastcpupid"},
2015 {KASAN_TAG_WIDTH
, KASAN_TAG_PGSHIFT
, KASAN_TAG_MASK
,
2016 &default_flag_spec
, "kasantag"},
2020 char *format_page_flags(char *buf
, char *end
, unsigned long flags
)
2022 unsigned long main_flags
= flags
& (BIT(NR_PAGEFLAGS
) - 1);
2023 bool append
= false;
2026 /* Page flags from the main area. */
2028 buf
= format_flags(buf
, end
, main_flags
, pageflag_names
);
2032 /* Page flags from the fields area */
2033 for (i
= 0; i
< ARRAY_SIZE(pff
); i
++) {
2034 /* Skip undefined fields. */
2038 /* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */
2045 buf
= string(buf
, end
, pff
[i
].name
, default_str_spec
);
2049 buf
= number(buf
, end
, (flags
>> pff
[i
].shift
) & pff
[i
].mask
,
2058 static noinline_for_stack
2059 char *flags_string(char *buf
, char *end
, void *flags_ptr
,
2060 struct printf_spec spec
, const char *fmt
)
2062 unsigned long flags
;
2063 const struct trace_print_flags
*names
;
2065 if (check_pointer(&buf
, end
, flags_ptr
, spec
))
2070 return format_page_flags(buf
, end
, *(unsigned long *)flags_ptr
);
2072 flags
= *(unsigned long *)flags_ptr
;
2073 names
= vmaflag_names
;
2076 flags
= (__force
unsigned long)(*(gfp_t
*)flags_ptr
);
2077 names
= gfpflag_names
;
2080 return error_string(buf
, end
, "(%pG?)", spec
);
2083 return format_flags(buf
, end
, flags
, names
);
2086 static noinline_for_stack
2087 char *fwnode_full_name_string(struct fwnode_handle
*fwnode
, char *buf
,
2092 /* Loop starting from the root node to the current node. */
2093 for (depth
= fwnode_count_parents(fwnode
); depth
>= 0; depth
--) {
2094 struct fwnode_handle
*__fwnode
=
2095 fwnode_get_nth_parent(fwnode
, depth
);
2097 buf
= string(buf
, end
, fwnode_get_name_prefix(__fwnode
),
2099 buf
= string(buf
, end
, fwnode_get_name(__fwnode
),
2102 fwnode_handle_put(__fwnode
);
2108 static noinline_for_stack
2109 char *device_node_string(char *buf
, char *end
, struct device_node
*dn
,
2110 struct printf_spec spec
, const char *fmt
)
2112 char tbuf
[sizeof("xxxx") + 1];
2115 char *buf_start
= buf
;
2116 struct property
*prop
;
2117 bool has_mult
, pass
;
2119 struct printf_spec str_spec
= spec
;
2120 str_spec
.field_width
= -1;
2123 return error_string(buf
, end
, "(%pO?)", spec
);
2125 if (!IS_ENABLED(CONFIG_OF
))
2126 return error_string(buf
, end
, "(%pOF?)", spec
);
2128 if (check_pointer(&buf
, end
, dn
, spec
))
2131 /* simple case without anything any more format specifiers */
2133 if (fmt
[0] == '\0' || strcspn(fmt
,"fnpPFcC") > 0)
2136 for (pass
= false; strspn(fmt
,"fnpPFcC"); fmt
++, pass
= true) {
2145 case 'f': /* full_name */
2146 buf
= fwnode_full_name_string(of_fwnode_handle(dn
), buf
,
2149 case 'n': /* name */
2150 p
= fwnode_get_name(of_fwnode_handle(dn
));
2151 precision
= str_spec
.precision
;
2152 str_spec
.precision
= strchrnul(p
, '@') - p
;
2153 buf
= string(buf
, end
, p
, str_spec
);
2154 str_spec
.precision
= precision
;
2156 case 'p': /* phandle */
2157 buf
= number(buf
, end
, (unsigned int)dn
->phandle
, default_dec_spec
);
2159 case 'P': /* path-spec */
2160 p
= fwnode_get_name(of_fwnode_handle(dn
));
2163 buf
= string(buf
, end
, p
, str_spec
);
2165 case 'F': /* flags */
2166 tbuf
[0] = of_node_check_flag(dn
, OF_DYNAMIC
) ? 'D' : '-';
2167 tbuf
[1] = of_node_check_flag(dn
, OF_DETACHED
) ? 'd' : '-';
2168 tbuf
[2] = of_node_check_flag(dn
, OF_POPULATED
) ? 'P' : '-';
2169 tbuf
[3] = of_node_check_flag(dn
, OF_POPULATED_BUS
) ? 'B' : '-';
2171 buf
= string_nocheck(buf
, end
, tbuf
, str_spec
);
2173 case 'c': /* major compatible string */
2174 ret
= of_property_read_string(dn
, "compatible", &p
);
2176 buf
= string(buf
, end
, p
, str_spec
);
2178 case 'C': /* full compatible string */
2180 of_property_for_each_string(dn
, "compatible", prop
, p
) {
2182 buf
= string_nocheck(buf
, end
, ",", str_spec
);
2183 buf
= string_nocheck(buf
, end
, "\"", str_spec
);
2184 buf
= string(buf
, end
, p
, str_spec
);
2185 buf
= string_nocheck(buf
, end
, "\"", str_spec
);
2195 return widen_string(buf
, buf
- buf_start
, end
, spec
);
2198 static noinline_for_stack
2199 char *fwnode_string(char *buf
, char *end
, struct fwnode_handle
*fwnode
,
2200 struct printf_spec spec
, const char *fmt
)
2202 struct printf_spec str_spec
= spec
;
2203 char *buf_start
= buf
;
2205 str_spec
.field_width
= -1;
2208 return error_string(buf
, end
, "(%pf?)", spec
);
2210 if (check_pointer(&buf
, end
, fwnode
, spec
))
2216 case 'P': /* name */
2217 buf
= string(buf
, end
, fwnode_get_name(fwnode
), str_spec
);
2219 case 'f': /* full_name */
2221 buf
= fwnode_full_name_string(fwnode
, buf
, end
);
2225 return widen_string(buf
, buf
- buf_start
, end
, spec
);
2228 /* Disable pointer hashing if requested */
2229 bool no_hash_pointers __ro_after_init
;
2230 EXPORT_SYMBOL_GPL(no_hash_pointers
);
2232 int __init
no_hash_pointers_enable(char *str
)
2234 if (no_hash_pointers
)
2237 no_hash_pointers
= true;
2239 pr_warn("**********************************************************\n");
2240 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
2242 pr_warn("** This system shows unhashed kernel memory addresses **\n");
2243 pr_warn("** via the console, logs, and other interfaces. This **\n");
2244 pr_warn("** might reduce the security of your system. **\n");
2246 pr_warn("** If you see this message and you are not debugging **\n");
2247 pr_warn("** the kernel, report this immediately to your system **\n");
2248 pr_warn("** administrator! **\n");
2250 pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
2251 pr_warn("**********************************************************\n");
2255 early_param("no_hash_pointers", no_hash_pointers_enable
);
2258 * Show a '%p' thing. A kernel extension is that the '%p' is followed
2259 * by an extra set of alphanumeric characters that are extended format
2262 * Please update scripts/checkpatch.pl when adding/removing conversion
2263 * characters. (Search for "check for vsprintf extension").
2265 * Right now we handle:
2267 * - 'S' For symbolic direct pointers (or function descriptors) with offset
2268 * - 's' For symbolic direct pointers (or function descriptors) without offset
2269 * - '[Ss]R' as above with __builtin_extract_return_addr() translation
2270 * - 'S[R]b' as above with module build ID (for use in backtraces)
2271 * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of
2272 * %ps and %pS. Be careful when re-using these specifiers.
2273 * - 'B' For backtraced symbolic direct pointers with offset
2274 * - 'Bb' as above with module build ID (for use in backtraces)
2275 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
2276 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
2277 * - 'b[l]' For a bitmap, the number of bits is determined by the field
2278 * width which must be explicitly specified either as part of the
2279 * format string '%32b[l]' or through '%*b[l]', [l] selects
2280 * range-list format instead of hex format
2281 * - 'M' For a 6-byte MAC address, it prints the address in the
2282 * usual colon-separated hex notation
2283 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
2284 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
2285 * with a dash-separated hex notation
2286 * - '[mM]R' For a 6-byte MAC address, Reverse order (Bluetooth)
2287 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
2288 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
2289 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
2291 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2292 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2293 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
2294 * IPv6 omits the colons (01020304...0f)
2295 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
2297 * Generic IPv4/IPv6 address (struct sockaddr *) that falls back to
2298 * [4] or [6] and is able to print port [p], flowinfo [f], scope [s]
2299 * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order
2300 * - 'I[6S]c' for IPv6 addresses printed as specified by
2301 * https://tools.ietf.org/html/rfc5952
2302 * - 'E[achnops]' For an escaped buffer, where rules are defined by combination
2303 * of the following flags (see string_escape_mem() for the
2306 * c - ESCAPE_SPECIAL
2312 * By default ESCAPE_ANY_NP is used.
2313 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
2314 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
2315 * Options for %pU are:
2316 * b big endian lower case hex (default)
2317 * B big endian UPPER case hex
2318 * l little endian lower case hex
2319 * L little endian UPPER case hex
2320 * big endian output byte order is:
2321 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
2322 * little endian output byte order is:
2323 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
2324 * - 'V' For a struct va_format which contains a format string * and va_list *,
2325 * call vsnprintf(->format, *->va_list).
2326 * Implements a "recursive vsnprintf".
2327 * Do not use this feature without some mechanism to verify the
2328 * correctness of the format string and va_list arguments.
2329 * - 'K' For a kernel pointer that should be hidden from unprivileged users.
2330 * Use only for procfs, sysfs and similar files, not printk(); please
2331 * read the documentation (path below) first.
2332 * - 'NF' For a netdev_features_t
2333 * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value.
2334 * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with
2335 * a certain separator (' ' by default):
2339 * The maximum supported length is 64 bytes of the input. Consider
2340 * to use print_hex_dump() for the larger input.
2341 * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives
2342 * (default assumed to be phys_addr_t, passed by reference)
2343 * - 'd[234]' For a dentry name (optionally 2-4 last components)
2344 * - 'D[234]' Same as 'd' but for a struct file
2345 * - 'g' For block_device name (gendisk + partition number)
2346 * - 't[RT][dt][r][s]' For time and date as represented by:
2349 * - 'C' For a clock, it prints the name (Common Clock Framework) or address
2350 * (legacy clock framework) of the clock
2351 * - 'Cn' For a clock, it prints the name (Common Clock Framework) or address
2352 * (legacy clock framework) of the clock
2353 * - 'G' For flags to be printed as a collection of symbolic strings that would
2354 * construct the specific value. Supported flags given by option:
2355 * p page flags (see struct page) given as pointer to unsigned long
2356 * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t
2357 * v vma flags (VM_*) given as pointer to unsigned long
2358 * - 'OF[fnpPcCF]' For a device tree object
2359 * Without any optional arguments prints the full_name
2360 * f device node full_name
2361 * n device node name
2362 * p device node phandle
2363 * P device node path spec (name + @unit)
2364 * F device node flags
2365 * c major compatible string
2366 * C full compatible string
2367 * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer
2368 * Without an option prints the full name of the node
2370 * P node name, including a possible unit address
2371 * - 'x' For printing the address unmodified. Equivalent to "%lx".
2372 * Please read the documentation (path below) before using!
2373 * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of
2374 * bpf_trace_printk() where [ku] prefix specifies either kernel (k)
2375 * or user (u) memory to probe, and:
2376 * s a string, equivalent to "%s" on direct vsnprintf() use
2378 * ** When making changes please also update:
2379 * Documentation/core-api/printk-formats.rst
2381 * Note: The default behaviour (unadorned %p) is to hash the address,
2382 * rendering it useful as a unique identifier.
2384 static noinline_for_stack
2385 char *pointer(const char *fmt
, char *buf
, char *end
, void *ptr
,
2386 struct printf_spec spec
)
2391 ptr
= dereference_symbol_descriptor(ptr
);
2394 return symbol_string(buf
, end
, ptr
, spec
, fmt
);
2397 return resource_string(buf
, end
, ptr
, spec
, fmt
);
2399 return hex_string(buf
, end
, ptr
, spec
, fmt
);
2403 return bitmap_list_string(buf
, end
, ptr
, spec
, fmt
);
2405 return bitmap_string(buf
, end
, ptr
, spec
, fmt
);
2407 case 'M': /* Colon separated: 00:01:02:03:04:05 */
2408 case 'm': /* Contiguous: 000102030405 */
2410 /* [mM]R (Reverse order; Bluetooth) */
2411 return mac_address_string(buf
, end
, ptr
, spec
, fmt
);
2412 case 'I': /* Formatted IP supported
2414 * 6: 0001:0203:...:0708
2415 * 6c: 1::708 or 1::1.2.3.4
2417 case 'i': /* Contiguous:
2418 * 4: 001.002.003.004
2421 return ip_addr_string(buf
, end
, ptr
, spec
, fmt
);
2423 return escaped_string(buf
, end
, ptr
, spec
, fmt
);
2425 return uuid_string(buf
, end
, ptr
, spec
, fmt
);
2427 return va_format(buf
, end
, ptr
, spec
, fmt
);
2429 return restricted_pointer(buf
, end
, ptr
, spec
);
2431 return netdev_bits(buf
, end
, ptr
, spec
, fmt
);
2433 return fourcc_string(buf
, end
, ptr
, spec
, fmt
);
2435 return address_val(buf
, end
, ptr
, spec
, fmt
);
2437 return dentry_name(buf
, end
, ptr
, spec
, fmt
);
2439 return time_and_date(buf
, end
, ptr
, spec
, fmt
);
2441 return clock(buf
, end
, ptr
, spec
, fmt
);
2443 return file_dentry_name(buf
, end
, ptr
, spec
, fmt
);
2446 return bdev_name(buf
, end
, ptr
, spec
, fmt
);
2450 return flags_string(buf
, end
, ptr
, spec
, fmt
);
2452 return device_node_string(buf
, end
, ptr
, spec
, fmt
+ 1);
2454 return fwnode_string(buf
, end
, ptr
, spec
, fmt
+ 1);
2456 return pointer_string(buf
, end
, ptr
, spec
);
2458 /* %pe with a non-ERR_PTR gets treated as plain %p */
2461 return err_ptr(buf
, end
, ptr
, spec
);
2466 return string(buf
, end
, ptr
, spec
);
2468 return error_string(buf
, end
, "(einval)", spec
);
2473 * default is to _not_ leak addresses, so hash before printing,
2474 * unless no_hash_pointers is specified on the command line.
2476 if (unlikely(no_hash_pointers
))
2477 return pointer_string(buf
, end
, ptr
, spec
);
2479 return ptr_to_id(buf
, end
, ptr
, spec
);
2483 * Helper function to decode printf style format.
2484 * Each call decode a token from the format and return the
2485 * number of characters read (or likely the delta where it wants
2486 * to go on the next call).
2487 * The decoded token is returned through the parameters
2489 * 'h', 'l', or 'L' for integer fields
2490 * 'z' support added 23/7/1999 S.H.
2491 * 'z' changed to 'Z' --davidm 1/25/99
2492 * 'Z' changed to 'z' --adobriyan 2017-01-25
2493 * 't' added for ptrdiff_t
2495 * @fmt: the format string
2496 * @type of the token returned
2497 * @flags: various flags such as +, -, # tokens..
2498 * @field_width: overwritten width
2499 * @base: base of the number (octal, hex, ...)
2500 * @precision: precision of a number
2501 * @qualifier: qualifier of a number (long, size_t, ...)
2503 static noinline_for_stack
2504 int format_decode(const char *fmt
, struct printf_spec
*spec
)
2506 const char *start
= fmt
;
2509 /* we finished early by reading the field width */
2510 if (spec
->type
== FORMAT_TYPE_WIDTH
) {
2511 if (spec
->field_width
< 0) {
2512 spec
->field_width
= -spec
->field_width
;
2513 spec
->flags
|= LEFT
;
2515 spec
->type
= FORMAT_TYPE_NONE
;
2519 /* we finished early by reading the precision */
2520 if (spec
->type
== FORMAT_TYPE_PRECISION
) {
2521 if (spec
->precision
< 0)
2522 spec
->precision
= 0;
2524 spec
->type
= FORMAT_TYPE_NONE
;
2529 spec
->type
= FORMAT_TYPE_NONE
;
2531 for (; *fmt
; ++fmt
) {
2536 /* Return the current non-format string */
2537 if (fmt
!= start
|| !*fmt
)
2543 while (1) { /* this also skips first '%' */
2549 case '-': spec
->flags
|= LEFT
; break;
2550 case '+': spec
->flags
|= PLUS
; break;
2551 case ' ': spec
->flags
|= SPACE
; break;
2552 case '#': spec
->flags
|= SPECIAL
; break;
2553 case '0': spec
->flags
|= ZEROPAD
; break;
2554 default: found
= false;
2561 /* get field width */
2562 spec
->field_width
= -1;
2565 spec
->field_width
= skip_atoi(&fmt
);
2566 else if (*fmt
== '*') {
2567 /* it's the next argument */
2568 spec
->type
= FORMAT_TYPE_WIDTH
;
2569 return ++fmt
- start
;
2573 /* get the precision */
2574 spec
->precision
= -1;
2577 if (isdigit(*fmt
)) {
2578 spec
->precision
= skip_atoi(&fmt
);
2579 if (spec
->precision
< 0)
2580 spec
->precision
= 0;
2581 } else if (*fmt
== '*') {
2582 /* it's the next argument */
2583 spec
->type
= FORMAT_TYPE_PRECISION
;
2584 return ++fmt
- start
;
2589 /* get the conversion qualifier */
2591 if (*fmt
== 'h' || _tolower(*fmt
) == 'l' ||
2592 *fmt
== 'z' || *fmt
== 't') {
2594 if (unlikely(qualifier
== *fmt
)) {
2595 if (qualifier
== 'l') {
2598 } else if (qualifier
== 'h') {
2609 spec
->type
= FORMAT_TYPE_CHAR
;
2610 return ++fmt
- start
;
2613 spec
->type
= FORMAT_TYPE_STR
;
2614 return ++fmt
- start
;
2617 spec
->type
= FORMAT_TYPE_PTR
;
2618 return ++fmt
- start
;
2621 spec
->type
= FORMAT_TYPE_PERCENT_CHAR
;
2622 return ++fmt
- start
;
2624 /* integer number formats - set up the flags and "break" */
2630 spec
->flags
|= SMALL
;
2639 spec
->flags
|= SIGN
;
2646 * Since %n poses a greater security risk than
2647 * utility, treat it as any other invalid or
2648 * unsupported format specifier.
2653 WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt
);
2654 spec
->type
= FORMAT_TYPE_INVALID
;
2658 if (qualifier
== 'L')
2659 spec
->type
= FORMAT_TYPE_LONG_LONG
;
2660 else if (qualifier
== 'l') {
2661 BUILD_BUG_ON(FORMAT_TYPE_ULONG
+ SIGN
!= FORMAT_TYPE_LONG
);
2662 spec
->type
= FORMAT_TYPE_ULONG
+ (spec
->flags
& SIGN
);
2663 } else if (qualifier
== 'z') {
2664 spec
->type
= FORMAT_TYPE_SIZE_T
;
2665 } else if (qualifier
== 't') {
2666 spec
->type
= FORMAT_TYPE_PTRDIFF
;
2667 } else if (qualifier
== 'H') {
2668 BUILD_BUG_ON(FORMAT_TYPE_UBYTE
+ SIGN
!= FORMAT_TYPE_BYTE
);
2669 spec
->type
= FORMAT_TYPE_UBYTE
+ (spec
->flags
& SIGN
);
2670 } else if (qualifier
== 'h') {
2671 BUILD_BUG_ON(FORMAT_TYPE_USHORT
+ SIGN
!= FORMAT_TYPE_SHORT
);
2672 spec
->type
= FORMAT_TYPE_USHORT
+ (spec
->flags
& SIGN
);
2674 BUILD_BUG_ON(FORMAT_TYPE_UINT
+ SIGN
!= FORMAT_TYPE_INT
);
2675 spec
->type
= FORMAT_TYPE_UINT
+ (spec
->flags
& SIGN
);
2678 return ++fmt
- start
;
2682 set_field_width(struct printf_spec
*spec
, int width
)
2684 spec
->field_width
= width
;
2685 if (WARN_ONCE(spec
->field_width
!= width
, "field width %d too large", width
)) {
2686 spec
->field_width
= clamp(width
, -FIELD_WIDTH_MAX
, FIELD_WIDTH_MAX
);
2691 set_precision(struct printf_spec
*spec
, int prec
)
2693 spec
->precision
= prec
;
2694 if (WARN_ONCE(spec
->precision
!= prec
, "precision %d too large", prec
)) {
2695 spec
->precision
= clamp(prec
, 0, PRECISION_MAX
);
2700 * vsnprintf - Format a string and place it in a buffer
2701 * @buf: The buffer to place the result into
2702 * @size: The size of the buffer, including the trailing null space
2703 * @fmt: The format string to use
2704 * @args: Arguments for the format string
2706 * This function generally follows C99 vsnprintf, but has some
2707 * extensions and a few limitations:
2709 * - ``%n`` is unsupported
2710 * - ``%p*`` is handled by pointer()
2712 * See pointer() or Documentation/core-api/printk-formats.rst for more
2713 * extensive description.
2715 * **Please update the documentation in both places when making changes**
2717 * The return value is the number of characters which would
2718 * be generated for the given input, excluding the trailing
2719 * '\0', as per ISO C99. If you want to have the exact
2720 * number of characters written into @buf as return value
2721 * (not including the trailing '\0'), use vscnprintf(). If the
2722 * return is greater than or equal to @size, the resulting
2723 * string is truncated.
2725 * If you're not already dealing with a va_list consider using snprintf().
2727 int vsnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
2729 unsigned long long num
;
2731 struct printf_spec spec
= {0};
2733 /* Reject out-of-range values early. Large positive sizes are
2734 used for unknown buffer sizes. */
2735 if (WARN_ON_ONCE(size
> INT_MAX
))
2741 /* Make sure end is always >= buf */
2748 const char *old_fmt
= fmt
;
2749 int read
= format_decode(fmt
, &spec
);
2753 switch (spec
.type
) {
2754 case FORMAT_TYPE_NONE
: {
2757 if (copy
> end
- str
)
2759 memcpy(str
, old_fmt
, copy
);
2765 case FORMAT_TYPE_WIDTH
:
2766 set_field_width(&spec
, va_arg(args
, int));
2769 case FORMAT_TYPE_PRECISION
:
2770 set_precision(&spec
, va_arg(args
, int));
2773 case FORMAT_TYPE_CHAR
: {
2776 if (!(spec
.flags
& LEFT
)) {
2777 while (--spec
.field_width
> 0) {
2784 c
= (unsigned char) va_arg(args
, int);
2788 while (--spec
.field_width
> 0) {
2796 case FORMAT_TYPE_STR
:
2797 str
= string(str
, end
, va_arg(args
, char *), spec
);
2800 case FORMAT_TYPE_PTR
:
2801 str
= pointer(fmt
, str
, end
, va_arg(args
, void *),
2803 while (isalnum(*fmt
))
2807 case FORMAT_TYPE_PERCENT_CHAR
:
2813 case FORMAT_TYPE_INVALID
:
2815 * Presumably the arguments passed gcc's type
2816 * checking, but there is no safe or sane way
2817 * for us to continue parsing the format and
2818 * fetching from the va_list; the remaining
2819 * specifiers and arguments would be out of
2825 switch (spec
.type
) {
2826 case FORMAT_TYPE_LONG_LONG
:
2827 num
= va_arg(args
, long long);
2829 case FORMAT_TYPE_ULONG
:
2830 num
= va_arg(args
, unsigned long);
2832 case FORMAT_TYPE_LONG
:
2833 num
= va_arg(args
, long);
2835 case FORMAT_TYPE_SIZE_T
:
2836 if (spec
.flags
& SIGN
)
2837 num
= va_arg(args
, ssize_t
);
2839 num
= va_arg(args
, size_t);
2841 case FORMAT_TYPE_PTRDIFF
:
2842 num
= va_arg(args
, ptrdiff_t);
2844 case FORMAT_TYPE_UBYTE
:
2845 num
= (unsigned char) va_arg(args
, int);
2847 case FORMAT_TYPE_BYTE
:
2848 num
= (signed char) va_arg(args
, int);
2850 case FORMAT_TYPE_USHORT
:
2851 num
= (unsigned short) va_arg(args
, int);
2853 case FORMAT_TYPE_SHORT
:
2854 num
= (short) va_arg(args
, int);
2856 case FORMAT_TYPE_INT
:
2857 num
= (int) va_arg(args
, int);
2860 num
= va_arg(args
, unsigned int);
2863 str
= number(str
, end
, num
, spec
);
2875 /* the trailing null byte doesn't count towards the total */
2879 EXPORT_SYMBOL(vsnprintf
);
2882 * vscnprintf - Format a string and place it in a buffer
2883 * @buf: The buffer to place the result into
2884 * @size: The size of the buffer, including the trailing null space
2885 * @fmt: The format string to use
2886 * @args: Arguments for the format string
2888 * The return value is the number of characters which have been written into
2889 * the @buf not including the trailing '\0'. If @size is == 0 the function
2892 * If you're not already dealing with a va_list consider using scnprintf().
2894 * See the vsnprintf() documentation for format string extensions over C99.
2896 int vscnprintf(char *buf
, size_t size
, const char *fmt
, va_list args
)
2900 i
= vsnprintf(buf
, size
, fmt
, args
);
2902 if (likely(i
< size
))
2908 EXPORT_SYMBOL(vscnprintf
);
2911 * snprintf - Format a string and place it in a buffer
2912 * @buf: The buffer to place the result into
2913 * @size: The size of the buffer, including the trailing null space
2914 * @fmt: The format string to use
2915 * @...: Arguments for the format string
2917 * The return value is the number of characters which would be
2918 * generated for the given input, excluding the trailing null,
2919 * as per ISO C99. If the return is greater than or equal to
2920 * @size, the resulting string is truncated.
2922 * See the vsnprintf() documentation for format string extensions over C99.
2924 int snprintf(char *buf
, size_t size
, const char *fmt
, ...)
2929 va_start(args
, fmt
);
2930 i
= vsnprintf(buf
, size
, fmt
, args
);
2935 EXPORT_SYMBOL(snprintf
);
2938 * scnprintf - Format a string and place it in a buffer
2939 * @buf: The buffer to place the result into
2940 * @size: The size of the buffer, including the trailing null space
2941 * @fmt: The format string to use
2942 * @...: Arguments for the format string
2944 * The return value is the number of characters written into @buf not including
2945 * the trailing '\0'. If @size is == 0 the function returns 0.
2948 int scnprintf(char *buf
, size_t size
, const char *fmt
, ...)
2953 va_start(args
, fmt
);
2954 i
= vscnprintf(buf
, size
, fmt
, args
);
2959 EXPORT_SYMBOL(scnprintf
);
2962 * vsprintf - Format a string and place it in a buffer
2963 * @buf: The buffer to place the result into
2964 * @fmt: The format string to use
2965 * @args: Arguments for the format string
2967 * The function returns the number of characters written
2968 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
2971 * If you're not already dealing with a va_list consider using sprintf().
2973 * See the vsnprintf() documentation for format string extensions over C99.
2975 int vsprintf(char *buf
, const char *fmt
, va_list args
)
2977 return vsnprintf(buf
, INT_MAX
, fmt
, args
);
2979 EXPORT_SYMBOL(vsprintf
);
2982 * sprintf - Format a string and place it in a buffer
2983 * @buf: The buffer to place the result into
2984 * @fmt: The format string to use
2985 * @...: Arguments for the format string
2987 * The function returns the number of characters written
2988 * into @buf. Use snprintf() or scnprintf() in order to avoid
2991 * See the vsnprintf() documentation for format string extensions over C99.
2993 int sprintf(char *buf
, const char *fmt
, ...)
2998 va_start(args
, fmt
);
2999 i
= vsnprintf(buf
, INT_MAX
, fmt
, args
);
3004 EXPORT_SYMBOL(sprintf
);
3006 #ifdef CONFIG_BINARY_PRINTF
3009 * vbin_printf() - VA arguments to binary data
3010 * bstr_printf() - Binary data to text string
3014 * vbin_printf - Parse a format string and place args' binary value in a buffer
3015 * @bin_buf: The buffer to place args' binary value
3016 * @size: The size of the buffer(by words(32bits), not characters)
3017 * @fmt: The format string to use
3018 * @args: Arguments for the format string
3020 * The format follows C99 vsnprintf, except %n is ignored, and its argument
3023 * The return value is the number of words(32bits) which would be generated for
3027 * If the return value is greater than @size, the resulting bin_buf is NOT
3028 * valid for bstr_printf().
3030 int vbin_printf(u32
*bin_buf
, size_t size
, const char *fmt
, va_list args
)
3032 struct printf_spec spec
= {0};
3036 str
= (char *)bin_buf
;
3037 end
= (char *)(bin_buf
+ size
);
3039 #define save_arg(type) \
3041 unsigned long long value; \
3042 if (sizeof(type) == 8) { \
3043 unsigned long long val8; \
3044 str = PTR_ALIGN(str, sizeof(u32)); \
3045 val8 = va_arg(args, unsigned long long); \
3046 if (str + sizeof(type) <= end) { \
3047 *(u32 *)str = *(u32 *)&val8; \
3048 *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \
3052 unsigned int val4; \
3053 str = PTR_ALIGN(str, sizeof(type)); \
3054 val4 = va_arg(args, int); \
3055 if (str + sizeof(type) <= end) \
3056 *(typeof(type) *)str = (type)(long)val4; \
3057 value = (unsigned long long)val4; \
3059 str += sizeof(type); \
3064 int read
= format_decode(fmt
, &spec
);
3068 switch (spec
.type
) {
3069 case FORMAT_TYPE_NONE
:
3070 case FORMAT_TYPE_PERCENT_CHAR
:
3072 case FORMAT_TYPE_INVALID
:
3075 case FORMAT_TYPE_WIDTH
:
3076 case FORMAT_TYPE_PRECISION
:
3077 width
= (int)save_arg(int);
3078 /* Pointers may require the width */
3080 set_field_width(&spec
, width
);
3083 case FORMAT_TYPE_CHAR
:
3087 case FORMAT_TYPE_STR
: {
3088 const char *save_str
= va_arg(args
, char *);
3089 const char *err_msg
;
3092 err_msg
= check_pointer_msg(save_str
);
3096 len
= strlen(save_str
) + 1;
3097 if (str
+ len
< end
)
3098 memcpy(str
, save_str
, len
);
3103 case FORMAT_TYPE_PTR
:
3104 /* Dereferenced pointers must be done now */
3106 /* Dereference of functions is still OK */
3115 if (!isalnum(*fmt
)) {
3119 str
= pointer(fmt
, str
, end
, va_arg(args
, void *),
3124 end
[-1] = '\0'; /* Must be nul terminated */
3126 /* skip all alphanumeric pointer suffixes */
3127 while (isalnum(*fmt
))
3132 switch (spec
.type
) {
3134 case FORMAT_TYPE_LONG_LONG
:
3135 save_arg(long long);
3137 case FORMAT_TYPE_ULONG
:
3138 case FORMAT_TYPE_LONG
:
3139 save_arg(unsigned long);
3141 case FORMAT_TYPE_SIZE_T
:
3144 case FORMAT_TYPE_PTRDIFF
:
3145 save_arg(ptrdiff_t);
3147 case FORMAT_TYPE_UBYTE
:
3148 case FORMAT_TYPE_BYTE
:
3151 case FORMAT_TYPE_USHORT
:
3152 case FORMAT_TYPE_SHORT
:
3162 return (u32
*)(PTR_ALIGN(str
, sizeof(u32
))) - bin_buf
;
3165 EXPORT_SYMBOL_GPL(vbin_printf
);
3168 * bstr_printf - Format a string from binary arguments and place it in a buffer
3169 * @buf: The buffer to place the result into
3170 * @size: The size of the buffer, including the trailing null space
3171 * @fmt: The format string to use
3172 * @bin_buf: Binary arguments for the format string
3174 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
3175 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
3176 * a binary buffer that generated by vbin_printf.
3178 * The format follows C99 vsnprintf, but has some extensions:
3179 * see vsnprintf comment for details.
3181 * The return value is the number of characters which would
3182 * be generated for the given input, excluding the trailing
3183 * '\0', as per ISO C99. If you want to have the exact
3184 * number of characters written into @buf as return value
3185 * (not including the trailing '\0'), use vscnprintf(). If the
3186 * return is greater than or equal to @size, the resulting
3187 * string is truncated.
3189 int bstr_printf(char *buf
, size_t size
, const char *fmt
, const u32
*bin_buf
)
3191 struct printf_spec spec
= {0};
3193 const char *args
= (const char *)bin_buf
;
3195 if (WARN_ON_ONCE(size
> INT_MAX
))
3201 #define get_arg(type) \
3203 typeof(type) value; \
3204 if (sizeof(type) == 8) { \
3205 args = PTR_ALIGN(args, sizeof(u32)); \
3206 *(u32 *)&value = *(u32 *)args; \
3207 *((u32 *)&value + 1) = *(u32 *)(args + 4); \
3209 args = PTR_ALIGN(args, sizeof(type)); \
3210 value = *(typeof(type) *)args; \
3212 args += sizeof(type); \
3216 /* Make sure end is always >= buf */
3223 const char *old_fmt
= fmt
;
3224 int read
= format_decode(fmt
, &spec
);
3228 switch (spec
.type
) {
3229 case FORMAT_TYPE_NONE
: {
3232 if (copy
> end
- str
)
3234 memcpy(str
, old_fmt
, copy
);
3240 case FORMAT_TYPE_WIDTH
:
3241 set_field_width(&spec
, get_arg(int));
3244 case FORMAT_TYPE_PRECISION
:
3245 set_precision(&spec
, get_arg(int));
3248 case FORMAT_TYPE_CHAR
: {
3251 if (!(spec
.flags
& LEFT
)) {
3252 while (--spec
.field_width
> 0) {
3258 c
= (unsigned char) get_arg(char);
3262 while (--spec
.field_width
> 0) {
3270 case FORMAT_TYPE_STR
: {
3271 const char *str_arg
= args
;
3272 args
+= strlen(str_arg
) + 1;
3273 str
= string(str
, end
, (char *)str_arg
, spec
);
3277 case FORMAT_TYPE_PTR
: {
3278 bool process
= false;
3280 /* Non function dereferences were already done */
3290 if (!isalnum(*fmt
)) {
3294 /* Pointer dereference was already processed */
3296 len
= copy
= strlen(args
);
3297 if (copy
> end
- str
)
3299 memcpy(str
, args
, copy
);
3305 str
= pointer(fmt
, str
, end
, get_arg(void *), spec
);
3307 while (isalnum(*fmt
))
3312 case FORMAT_TYPE_PERCENT_CHAR
:
3318 case FORMAT_TYPE_INVALID
:
3322 unsigned long long num
;
3324 switch (spec
.type
) {
3326 case FORMAT_TYPE_LONG_LONG
:
3327 num
= get_arg(long long);
3329 case FORMAT_TYPE_ULONG
:
3330 case FORMAT_TYPE_LONG
:
3331 num
= get_arg(unsigned long);
3333 case FORMAT_TYPE_SIZE_T
:
3334 num
= get_arg(size_t);
3336 case FORMAT_TYPE_PTRDIFF
:
3337 num
= get_arg(ptrdiff_t);
3339 case FORMAT_TYPE_UBYTE
:
3340 num
= get_arg(unsigned char);
3342 case FORMAT_TYPE_BYTE
:
3343 num
= get_arg(signed char);
3345 case FORMAT_TYPE_USHORT
:
3346 num
= get_arg(unsigned short);
3348 case FORMAT_TYPE_SHORT
:
3349 num
= get_arg(short);
3351 case FORMAT_TYPE_UINT
:
3352 num
= get_arg(unsigned int);
3358 str
= number(str
, end
, num
, spec
);
3360 } /* switch(spec.type) */
3373 /* the trailing null byte doesn't count towards the total */
3376 EXPORT_SYMBOL_GPL(bstr_printf
);
3379 * bprintf - Parse a format string and place args' binary value in a buffer
3380 * @bin_buf: The buffer to place args' binary value
3381 * @size: The size of the buffer(by words(32bits), not characters)
3382 * @fmt: The format string to use
3383 * @...: Arguments for the format string
3385 * The function returns the number of words(u32) written
3388 int bprintf(u32
*bin_buf
, size_t size
, const char *fmt
, ...)
3393 va_start(args
, fmt
);
3394 ret
= vbin_printf(bin_buf
, size
, fmt
, args
);
3399 EXPORT_SYMBOL_GPL(bprintf
);
3401 #endif /* CONFIG_BINARY_PRINTF */
3404 * vsscanf - Unformat a buffer into a list of arguments
3405 * @buf: input buffer
3406 * @fmt: format of buffer
3409 int vsscanf(const char *buf
, const char *fmt
, va_list args
)
3411 const char *str
= buf
;
3419 unsigned long long u
;
3425 /* skip any white space in format */
3426 /* white space in format matches any amount of
3427 * white space, including none, in the input.
3429 if (isspace(*fmt
)) {
3430 fmt
= skip_spaces(++fmt
);
3431 str
= skip_spaces(str
);
3434 /* anything that is not a conversion must match exactly */
3435 if (*fmt
!= '%' && *fmt
) {
3436 if (*fmt
++ != *str
++)
3445 /* skip this conversion.
3446 * advance both strings to next white space
3451 while (!isspace(*fmt
) && *fmt
!= '%' && *fmt
) {
3452 /* '%*[' not yet supported, invalid format */
3457 while (!isspace(*str
) && *str
)
3462 /* get field width */
3464 if (isdigit(*fmt
)) {
3465 field_width
= skip_atoi(&fmt
);
3466 if (field_width
<= 0)
3470 /* get conversion qualifier */
3472 if (*fmt
== 'h' || _tolower(*fmt
) == 'l' ||
3475 if (unlikely(qualifier
== *fmt
)) {
3476 if (qualifier
== 'h') {
3479 } else if (qualifier
== 'l') {
3490 /* return number of characters read so far */
3491 *va_arg(args
, int *) = str
- buf
;
3505 char *s
= (char *)va_arg(args
, char*);
3506 if (field_width
== -1)
3510 } while (--field_width
> 0 && *str
);
3516 char *s
= (char *)va_arg(args
, char *);
3517 if (field_width
== -1)
3518 field_width
= SHRT_MAX
;
3519 /* first, skip leading white space in buffer */
3520 str
= skip_spaces(str
);
3522 /* now copy until next white space */
3523 while (*str
&& !isspace(*str
) && field_width
--)
3530 * Warning: This implementation of the '[' conversion specifier
3531 * deviates from its glibc counterpart in the following ways:
3532 * (1) It does NOT support ranges i.e. '-' is NOT a special
3534 * (2) It cannot match the closing bracket ']' itself
3535 * (3) A field width is required
3536 * (4) '%*[' (discard matching input) is currently not supported
3539 * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]",
3540 * buf1, buf2, buf3);
3546 char *s
= (char *)va_arg(args
, char *);
3547 DECLARE_BITMAP(set
, 256) = {0};
3548 unsigned int len
= 0;
3549 bool negate
= (*fmt
== '^');
3551 /* field width is required */
3552 if (field_width
== -1)
3558 for ( ; *fmt
&& *fmt
!= ']'; ++fmt
, ++len
)
3559 set_bit((u8
)*fmt
, set
);
3561 /* no ']' or no character set found */
3567 bitmap_complement(set
, set
, 256);
3568 /* exclude null '\0' byte */
3572 /* match must be non-empty */
3573 if (!test_bit((u8
)*str
, set
))
3576 while (test_bit((u8
)*str
, set
) && field_width
--)
3598 /* looking for '%' in str */
3603 /* invalid format; stop here */
3607 /* have some sort of integer conversion.
3608 * first, skip white space in buffer.
3610 str
= skip_spaces(str
);
3613 if (is_sign
&& digit
== '-') {
3614 if (field_width
== 1)
3621 || (base
== 16 && !isxdigit(digit
))
3622 || (base
== 10 && !isdigit(digit
))
3623 || (base
== 8 && (!isdigit(digit
) || digit
> '7'))
3624 || (base
== 0 && !isdigit(digit
)))
3628 val
.s
= simple_strntoll(str
,
3629 field_width
>= 0 ? field_width
: INT_MAX
,
3632 val
.u
= simple_strntoull(str
,
3633 field_width
>= 0 ? field_width
: INT_MAX
,
3636 switch (qualifier
) {
3637 case 'H': /* that's 'hh' in format */
3639 *va_arg(args
, signed char *) = val
.s
;
3641 *va_arg(args
, unsigned char *) = val
.u
;
3645 *va_arg(args
, short *) = val
.s
;
3647 *va_arg(args
, unsigned short *) = val
.u
;
3651 *va_arg(args
, long *) = val
.s
;
3653 *va_arg(args
, unsigned long *) = val
.u
;
3657 *va_arg(args
, long long *) = val
.s
;
3659 *va_arg(args
, unsigned long long *) = val
.u
;
3662 *va_arg(args
, size_t *) = val
.u
;
3666 *va_arg(args
, int *) = val
.s
;
3668 *va_arg(args
, unsigned int *) = val
.u
;
3680 EXPORT_SYMBOL(vsscanf
);
3683 * sscanf - Unformat a buffer into a list of arguments
3684 * @buf: input buffer
3685 * @fmt: formatting of buffer
3686 * @...: resulting arguments
3688 int sscanf(const char *buf
, const char *fmt
, ...)
3693 va_start(args
, fmt
);
3694 i
= vsscanf(buf
, fmt
, args
);
3699 EXPORT_SYMBOL(sscanf
);