diff options
Diffstat (limited to 'lib/vsprintf.c')
| -rw-r--r-- | lib/vsprintf.c | 2977 |
1 files changed, 2160 insertions, 817 deletions
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 739a36366b79..a3790c43a0ab 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1,3 +1,4 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * linux/lib/vsprintf.c * @@ -16,7 +17,11 @@ * - scnprintf and vscnprintf */ -#include <stdarg.h> +#include <linux/stdarg.h> +#include <linux/build_bug.h> +#include <linux/clk.h> +#include <linux/clk-provider.h> +#include <linux/errname.h> #include <linux/module.h> /* for KSYM_SYMBOL_LEN */ #include <linux/types.h> #include <linux/string.h> @@ -26,36 +31,87 @@ #include <linux/math64.h> #include <linux/uaccess.h> #include <linux/ioport.h> +#include <linux/dcache.h> +#include <linux/cred.h> +#include <linux/rtc.h> +#include <linux/sprintf.h> +#include <linux/time.h> +#include <linux/uuid.h> +#include <linux/of.h> #include <net/addrconf.h> +#include <linux/siphash.h> +#include <linux/compiler.h> +#include <linux/property.h> +#include <linux/notifier.h> +#ifdef CONFIG_BLOCK +#include <linux/blkdev.h> +#endif + +#include "../mm/internal.h" /* For the trace_print_flags arrays */ #include <asm/page.h> /* for PAGE_SIZE */ -#include <asm/sections.h> /* for dereference_function_descriptor() */ +#include <asm/byteorder.h> /* cpu_to_le16 */ +#include <linux/unaligned.h> +#include <linux/string_helpers.h> #include "kstrtox.h" -/** - * simple_strtoull - convert a string to an unsigned long long - * @cp: The start of the string - * @endp: A pointer to the end of the parsed string will be placed here - * @base: The number base to use +/* Disable pointer hashing if requested */ +bool no_hash_pointers __ro_after_init; +EXPORT_SYMBOL_GPL(no_hash_pointers); + +/* + * Hashed pointers policy selected by "hash_pointers=..." boot param * - * This function is obsolete. Please use kstrtoull instead. + * `auto` - Hashed pointers enabled unless disabled by slub_debug_enabled=true + * `always` - Hashed pointers enabled unconditionally + * `never` - Hashed pointers disabled unconditionally */ -unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) +enum hash_pointers_policy { + HASH_PTR_AUTO = 0, + HASH_PTR_ALWAYS, + HASH_PTR_NEVER +}; +static enum hash_pointers_policy hash_pointers_mode __initdata; + +noinline +static unsigned long long simple_strntoull(const char *startp, char **endp, unsigned int base, size_t max_chars) { - unsigned long long result; + const char *cp; + unsigned long long result = 0ULL; + size_t prefix_chars; unsigned int rv; - cp = _parse_integer_fixup_radix(cp, &base); - rv = _parse_integer(cp, base, &result); - /* FIXME */ - cp += (rv & ~KSTRTOX_OVERFLOW); + cp = _parse_integer_fixup_radix(startp, &base); + prefix_chars = cp - startp; + if (prefix_chars < max_chars) { + rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars); + /* FIXME */ + cp += (rv & ~KSTRTOX_OVERFLOW); + } else { + /* Field too short for prefix + digit, skip over without converting */ + cp = startp + max_chars; + } if (endp) *endp = (char *)cp; return result; } + +/** + * simple_strtoull - convert a string to an unsigned long long + * @cp: The start of the string + * @endp: A pointer to the end of the parsed string will be placed here + * @base: The number base to use + * + * This function has caveats. Please use kstrtoull instead. + */ +noinline +unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) +{ + return simple_strntoull(cp, endp, base, INT_MAX); +} EXPORT_SYMBOL(simple_strtoull); /** @@ -64,7 +120,7 @@ EXPORT_SYMBOL(simple_strtoull); * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use * - * This function is obsolete. Please use kstrtoul instead. + * This function has caveats. Please use kstrtoul instead. */ unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) { @@ -72,13 +128,20 @@ unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) } EXPORT_SYMBOL(simple_strtoul); +unsigned long simple_strntoul(const char *cp, char **endp, unsigned int base, + size_t max_chars) +{ + return simple_strntoull(cp, endp, base, max_chars); +} +EXPORT_SYMBOL(simple_strntoul); + /** * simple_strtol - convert a string to a signed long * @cp: The start of the string * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use * - * This function is obsolete. Please use kstrtol instead. + * This function has caveats. Please use kstrtol instead. */ long simple_strtol(const char *cp, char **endp, unsigned int base) { @@ -89,170 +152,185 @@ long simple_strtol(const char *cp, char **endp, unsigned int base) } EXPORT_SYMBOL(simple_strtol); +noinline +static long long simple_strntoll(const char *cp, char **endp, unsigned int base, size_t max_chars) +{ + /* + * simple_strntoull() safely handles receiving max_chars==0 in the + * case cp[0] == '-' && max_chars == 1. + * If max_chars == 0 we can drop through and pass it to simple_strntoull() + * and the content of *cp is irrelevant. + */ + if (*cp == '-' && max_chars > 0) + return -simple_strntoull(cp + 1, endp, base, max_chars - 1); + + return simple_strntoull(cp, endp, base, max_chars); +} + /** * simple_strtoll - convert a string to a signed long long * @cp: The start of the string * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use * - * This function is obsolete. Please use kstrtoll instead. + * This function has caveats. Please use kstrtoll instead. */ long long simple_strtoll(const char *cp, char **endp, unsigned int base) { - if (*cp == '-') - return -simple_strtoull(cp + 1, endp, base); - - return simple_strtoull(cp, endp, base); + return simple_strntoll(cp, endp, base, INT_MAX); } EXPORT_SYMBOL(simple_strtoll); -static noinline_for_stack -int skip_atoi(const char **s) +static inline int skip_atoi(const char **s) { int i = 0; - while (isdigit(**s)) + do { i = i*10 + *((*s)++) - '0'; + } while (isdigit(**s)); return i; } -/* Decimal conversion is by far the most typical, and is used - * for /proc and /sys data. This directly impacts e.g. top performance - * with many processes running. We optimize it for speed - * using ideas described at <http://www.cs.uiowa.edu/~jones/bcd/divide.html> - * (with permission from the author, Douglas W. Jones). +/* + * Decimal conversion is by far the most typical, and is used for + * /proc and /sys data. This directly impacts e.g. top performance + * with many processes running. We optimize it for speed by emitting + * two characters at a time, using a 200 byte lookup table. This + * roughly halves the number of multiplications compared to computing + * the digits one at a time. Implementation strongly inspired by the + * previous version, which in turn used ideas described at + * <http://www.cs.uiowa.edu/~jones/bcd/divide.html> (with permission + * from the author, Douglas W. Jones). + * + * It turns out there is precisely one 26 bit fixed-point + * approximation a of 64/100 for which x/100 == (x * (u64)a) >> 32 + * holds for all x in [0, 10^8-1], namely a = 0x28f5c29. The actual + * range happens to be somewhat larger (x <= 1073741898), but that's + * irrelevant for our purpose. + * + * For dividing a number in the range [10^4, 10^6-1] by 100, we still + * need a 32x32->64 bit multiply, so we simply use the same constant. + * + * For dividing a number in the range [100, 10^4-1] by 100, there are + * several options. The simplest is (x * 0x147b) >> 19, which is valid + * for all x <= 43698. */ -#if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64 -/* Formats correctly any integer in [0, 999999999] */ +static const u16 decpair[100] = { +#define _(x) (__force u16) cpu_to_le16(((x % 10) | ((x / 10) << 8)) + 0x3030) + _( 0), _( 1), _( 2), _( 3), _( 4), _( 5), _( 6), _( 7), _( 8), _( 9), + _(10), _(11), _(12), _(13), _(14), _(15), _(16), _(17), _(18), _(19), + _(20), _(21), _(22), _(23), _(24), _(25), _(26), _(27), _(28), _(29), + _(30), _(31), _(32), _(33), _(34), _(35), _(36), _(37), _(38), _(39), + _(40), _(41), _(42), _(43), _(44), _(45), _(46), _(47), _(48), _(49), + _(50), _(51), _(52), _(53), _(54), _(55), _(56), _(57), _(58), _(59), + _(60), _(61), _(62), _(63), _(64), _(65), _(66), _(67), _(68), _(69), + _(70), _(71), _(72), _(73), _(74), _(75), _(76), _(77), _(78), _(79), + _(80), _(81), _(82), _(83), _(84), _(85), _(86), _(87), _(88), _(89), + _(90), _(91), _(92), _(93), _(94), _(95), _(96), _(97), _(98), _(99), +#undef _ +}; + +/* + * This will print a single '0' even if r == 0, since we would + * immediately jump to out_r where two 0s would be written but only + * one of them accounted for in buf. This is needed by ip4_string + * below. All other callers pass a non-zero value of r. +*/ static noinline_for_stack -char *put_dec_full9(char *buf, unsigned q) +char *put_dec_trunc8(char *buf, unsigned r) { - unsigned r; + unsigned q; - /* - * Possible ways to approx. divide by 10 - * (x * 0x1999999a) >> 32 x < 1073741829 (multiply must be 64-bit) - * (x * 0xcccd) >> 19 x < 81920 (x < 262149 when 64-bit mul) - * (x * 0x6667) >> 18 x < 43699 - * (x * 0x3334) >> 17 x < 16389 - * (x * 0x199a) >> 16 x < 16389 - * (x * 0x0ccd) >> 15 x < 16389 - * (x * 0x0667) >> 14 x < 2739 - * (x * 0x0334) >> 13 x < 1029 - * (x * 0x019a) >> 12 x < 1029 - * (x * 0x00cd) >> 11 x < 1029 shorter code than * 0x67 (on i386) - * (x * 0x0067) >> 10 x < 179 - * (x * 0x0034) >> 9 x < 69 same - * (x * 0x001a) >> 8 x < 69 same - * (x * 0x000d) >> 7 x < 69 same, shortest code (on i386) - * (x * 0x0007) >> 6 x < 19 - * See <http://www.cs.uiowa.edu/~jones/bcd/divide.html> - */ - r = (q * (uint64_t)0x1999999a) >> 32; - *buf++ = (q - 10 * r) + '0'; /* 1 */ - q = (r * (uint64_t)0x1999999a) >> 32; - *buf++ = (r - 10 * q) + '0'; /* 2 */ - r = (q * (uint64_t)0x1999999a) >> 32; - *buf++ = (q - 10 * r) + '0'; /* 3 */ - q = (r * (uint64_t)0x1999999a) >> 32; - *buf++ = (r - 10 * q) + '0'; /* 4 */ - r = (q * (uint64_t)0x1999999a) >> 32; - *buf++ = (q - 10 * r) + '0'; /* 5 */ - /* Now value is under 10000, can avoid 64-bit multiply */ - q = (r * 0x199a) >> 16; - *buf++ = (r - 10 * q) + '0'; /* 6 */ - r = (q * 0xcd) >> 11; - *buf++ = (q - 10 * r) + '0'; /* 7 */ - q = (r * 0xcd) >> 11; - *buf++ = (r - 10 * q) + '0'; /* 8 */ - *buf++ = q + '0'; /* 9 */ + /* 1 <= r < 10^8 */ + if (r < 100) + goto out_r; + + /* 100 <= r < 10^8 */ + q = (r * (u64)0x28f5c29) >> 32; + *((u16 *)buf) = decpair[r - 100*q]; + buf += 2; + + /* 1 <= q < 10^6 */ + if (q < 100) + goto out_q; + + /* 100 <= q < 10^6 */ + r = (q * (u64)0x28f5c29) >> 32; + *((u16 *)buf) = decpair[q - 100*r]; + buf += 2; + + /* 1 <= r < 10^4 */ + if (r < 100) + goto out_r; + + /* 100 <= r < 10^4 */ + q = (r * 0x147b) >> 19; + *((u16 *)buf) = decpair[r - 100*q]; + buf += 2; +out_q: + /* 1 <= q < 100 */ + r = q; +out_r: + /* 1 <= r < 100 */ + *((u16 *)buf) = decpair[r]; + buf += r < 10 ? 1 : 2; return buf; } -#endif -/* Similar to above but do not pad with zeros. - * Code can be easily arranged to print 9 digits too, but our callers - * always call put_dec_full9() instead when the number has 9 decimal digits. - */ +#if BITS_PER_LONG == 64 && BITS_PER_LONG_LONG == 64 static noinline_for_stack -char *put_dec_trunc8(char *buf, unsigned r) +char *put_dec_full8(char *buf, unsigned r) { unsigned q; - /* Copy of previous function's body with added early returns */ - while (r >= 10000) { - q = r + '0'; - r = (r * (uint64_t)0x1999999a) >> 32; - *buf++ = q - 10*r; - } + /* 0 <= r < 10^8 */ + q = (r * (u64)0x28f5c29) >> 32; + *((u16 *)buf) = decpair[r - 100*q]; + buf += 2; - q = (r * 0x199a) >> 16; /* r <= 9999 */ - *buf++ = (r - 10 * q) + '0'; - if (q == 0) - return buf; - r = (q * 0xcd) >> 11; /* q <= 999 */ - *buf++ = (q - 10 * r) + '0'; - if (r == 0) - return buf; - q = (r * 0xcd) >> 11; /* r <= 99 */ - *buf++ = (r - 10 * q) + '0'; - if (q == 0) - return buf; - *buf++ = q + '0'; /* q <= 9 */ - return buf; -} + /* 0 <= q < 10^6 */ + r = (q * (u64)0x28f5c29) >> 32; + *((u16 *)buf) = decpair[q - 100*r]; + buf += 2; -/* There are two algorithms to print larger numbers. - * One is generic: divide by 1000000000 and repeatedly print - * groups of (up to) 9 digits. It's conceptually simple, - * but requires a (unsigned long long) / 1000000000 division. - * - * Second algorithm splits 64-bit unsigned long long into 16-bit chunks, - * manipulates them cleverly and generates groups of 4 decimal digits. - * It so happens that it does NOT require long long division. - * - * If long is > 32 bits, division of 64-bit values is relatively easy, - * and we will use the first algorithm. - * If long long is > 64 bits (strange architecture with VERY large long long), - * second algorithm can't be used, and we again use the first one. - * - * Else (if long is 32 bits and long long is 64 bits) we use second one. - */ + /* 0 <= r < 10^4 */ + q = (r * 0x147b) >> 19; + *((u16 *)buf) = decpair[r - 100*q]; + buf += 2; -#if BITS_PER_LONG != 32 || BITS_PER_LONG_LONG != 64 - -/* First algorithm: generic */ + /* 0 <= q < 100 */ + *((u16 *)buf) = decpair[q]; + buf += 2; + return buf; +} -static +static noinline_for_stack char *put_dec(char *buf, unsigned long long n) { - if (n >= 100*1000*1000) { - while (n >= 1000*1000*1000) - buf = put_dec_full9(buf, do_div(n, 1000*1000*1000)); - if (n >= 100*1000*1000) - return put_dec_full9(buf, n); - } + if (n >= 100*1000*1000) + buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); + /* 1 <= n <= 1.6e11 */ + if (n >= 100*1000*1000) + buf = put_dec_full8(buf, do_div(n, 100*1000*1000)); + /* 1 <= n < 1e8 */ return put_dec_trunc8(buf, n); } -#else - -/* Second algorithm: valid only for 64-bit long longs */ +#elif BITS_PER_LONG == 32 && BITS_PER_LONG_LONG == 64 -/* See comment in put_dec_full9 for choice of constants */ -static noinline_for_stack -void put_dec_full4(char *buf, unsigned q) +static void +put_dec_full4(char *buf, unsigned r) { - unsigned r; - r = (q * 0xccd) >> 15; - buf[0] = (q - 10 * r) + '0'; - q = (r * 0xcd) >> 11; - buf[1] = (r - 10 * q) + '0'; - r = (q * 0xcd) >> 11; - buf[2] = (q - 10 * r) + '0'; - buf[3] = r + '0'; + unsigned q; + + /* 0 <= r < 10^4 */ + q = (r * 0x147b) >> 19; + *((u16 *)buf) = decpair[r - 100*q]; + buf += 2; + /* 0 <= q < 100 */ + *((u16 *)buf) = decpair[q]; } /* @@ -260,9 +338,9 @@ void put_dec_full4(char *buf, unsigned q) * The approximation x/10000 == (x * 0x346DC5D7) >> 43 * holds for all x < 1,128,869,999. The largest value this * helper will ever be asked to convert is 1,125,520,955. - * (d1 in the put_dec code, assuming n is all-ones). + * (second call in the put_dec code, assuming n is all-ones). */ -static +static noinline_for_stack unsigned put_dec_helper4(char *buf, unsigned x) { uint32_t q = (x * (uint64_t)0x346DC5D7) >> 43; @@ -289,6 +367,8 @@ char *put_dec(char *buf, unsigned long long n) d2 = (h ) & 0xffff; d3 = (h >> 16); /* implicit "& 0xffff" */ + /* n = 2^48 d3 + 2^32 d2 + 2^16 d1 + d0 + = 281_4749_7671_0656 d3 + 42_9496_7296 d2 + 6_5536 d1 + d0 */ q = 656 * d3 + 7296 * d2 + 5536 * d1 + ((uint32_t)n & 0xffff); q = put_dec_helper4(buf, q); @@ -316,9 +396,10 @@ char *put_dec(char *buf, unsigned long long n) * * If speed is not important, use snprintf(). It's easy to read the code. */ -int num_to_str(char *buf, int size, unsigned long long num) +int num_to_str(char *buf, int size, unsigned long long num, unsigned int width) { - char tmp[sizeof(num) * 3]; + /* put_dec requires 2-byte alignment of the buffer. */ + char tmp[sizeof(num) * 3] __aligned(2); int idx, len; /* put_dec() may work incorrectly for num = 0 (generate "", not "0") */ @@ -329,66 +410,70 @@ int num_to_str(char *buf, int size, unsigned long long num) len = put_dec(tmp, num) - tmp; } - if (len > size) + if (len > size || width > size) return 0; + + if (width > len) { + width = width - len; + for (idx = 0; idx < width; idx++) + buf[idx] = ' '; + } else { + width = 0; + } + for (idx = 0; idx < len; ++idx) - buf[idx] = tmp[len - idx - 1]; - return len; + buf[idx + width] = tmp[len - idx - 1]; + + return len + width; } -#define ZEROPAD 1 /* pad with zero */ -#define SIGN 2 /* unsigned/signed long */ +#define SIGN 1 /* unsigned/signed */ +#define LEFT 2 /* left justified */ #define PLUS 4 /* show plus */ #define SPACE 8 /* space if plus */ -#define LEFT 16 /* left justified */ +#define ZEROPAD 16 /* pad with zero, must be 16 == '0' - ' ' */ #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ -enum format_type { - FORMAT_TYPE_NONE, /* Just a string part */ - FORMAT_TYPE_WIDTH, - FORMAT_TYPE_PRECISION, - FORMAT_TYPE_CHAR, - FORMAT_TYPE_STR, - FORMAT_TYPE_PTR, - FORMAT_TYPE_PERCENT_CHAR, - FORMAT_TYPE_INVALID, - FORMAT_TYPE_LONG_LONG, - FORMAT_TYPE_ULONG, - FORMAT_TYPE_LONG, - FORMAT_TYPE_UBYTE, - FORMAT_TYPE_BYTE, - FORMAT_TYPE_USHORT, - FORMAT_TYPE_SHORT, - FORMAT_TYPE_UINT, - FORMAT_TYPE_INT, - FORMAT_TYPE_NRCHARS, - FORMAT_TYPE_SIZE_T, - FORMAT_TYPE_PTRDIFF +static_assert(ZEROPAD == ('0' - ' ')); +static_assert(SMALL == ('a' ^ 'A')); + +enum format_state { + FORMAT_STATE_NONE, /* Just a string part */ + FORMAT_STATE_NUM, + FORMAT_STATE_WIDTH, + FORMAT_STATE_PRECISION, + FORMAT_STATE_CHAR, + FORMAT_STATE_STR, + FORMAT_STATE_PTR, + FORMAT_STATE_PERCENT_CHAR, + FORMAT_STATE_INVALID, }; struct printf_spec { - u8 type; /* format_type enum */ - u8 flags; /* flags to number() */ - u8 base; /* number base, 8, 10 or 16 only */ - u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */ - s16 field_width; /* width of output field */ - s16 precision; /* # of digits/chars */ -}; + unsigned char flags; /* flags to number() */ + unsigned char base; /* number base, 8, 10 or 16 only */ + short precision; /* # of digits/chars */ + int field_width; /* width of output field */ +} __packed; +static_assert(sizeof(struct printf_spec) == 8); + +#define FIELD_WIDTH_MAX ((1 << 23) - 1) +#define PRECISION_MAX ((1 << 15) - 1) static noinline_for_stack char *number(char *buf, char *end, unsigned long long num, struct printf_spec spec) { - /* we are called with base 8, 10 or 16, only, thus don't need "G..." */ - static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */ - - char tmp[66]; + /* put_dec requires 2-byte alignment of the buffer. */ + char tmp[3 * sizeof(num)] __aligned(2); char sign; char locase; int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); int i; bool is_zero = num == 0LL; + int field_width = spec.field_width; + int precision = spec.precision; /* locase = 0 or 0x20. ORing digits or letters with 'locase' * produces same digits or (maybe lowercased) letters */ @@ -400,31 +485,26 @@ char *number(char *buf, char *end, unsigned long long num, if ((signed long long)num < 0) { sign = '-'; num = -(signed long long)num; - spec.field_width--; + field_width--; } else if (spec.flags & PLUS) { sign = '+'; - spec.field_width--; + field_width--; } else if (spec.flags & SPACE) { sign = ' '; - spec.field_width--; + field_width--; } } if (need_pfx) { if (spec.base == 16) - spec.field_width -= 2; + field_width -= 2; else if (!is_zero) - spec.field_width--; + field_width--; } /* generate full string in tmp[], in reverse order */ i = 0; if (num < spec.base) - tmp[i++] = digits[num] | locase; - /* Generic code, for any base: - else do { - tmp[i++] = (digits[do_div(num,base)] | locase); - } while (num != 0); - */ + tmp[i++] = hex_asc_upper[num] | locase; else if (spec.base != 10) { /* 8 or 16 */ int mask = spec.base - 1; int shift = 3; @@ -432,7 +512,7 @@ char *number(char *buf, char *end, unsigned long long num, if (spec.base == 16) shift = 4; do { - tmp[i++] = (digits[((unsigned char)num) & mask] | locase); + tmp[i++] = (hex_asc_upper[((unsigned char)num) & mask] | locase); num >>= shift; } while (num); } else { /* base 10 */ @@ -440,12 +520,12 @@ char *number(char *buf, char *end, unsigned long long num, } /* printing 100 using %2d gives "100", not "00" */ - if (i > spec.precision) - spec.precision = i; + if (i > precision) + precision = i; /* leading space padding */ - spec.field_width -= spec.precision; - if (!(spec.flags & (ZEROPAD+LEFT))) { - while (--spec.field_width >= 0) { + field_width -= precision; + if (!(spec.flags & (ZEROPAD | LEFT))) { + while (--field_width >= 0) { if (buf < end) *buf = ' '; ++buf; @@ -472,15 +552,16 @@ char *number(char *buf, char *end, unsigned long long num, } /* zero or space padding */ if (!(spec.flags & LEFT)) { - char c = (spec.flags & ZEROPAD) ? '0' : ' '; - while (--spec.field_width >= 0) { + char c = ' ' + (spec.flags & ZEROPAD); + + while (--field_width >= 0) { if (buf < end) *buf = c; ++buf; } } /* hmm even more zero padding? */ - while (i <= --spec.precision) { + while (i <= --precision) { if (buf < end) *buf = '0'; ++buf; @@ -492,7 +573,7 @@ char *number(char *buf, char *end, unsigned long long num, ++buf; } /* trailing space padding */ - while (--spec.field_width >= 0) { + while (--field_width >= 0) { if (buf < end) *buf = ' '; ++buf; @@ -501,36 +582,409 @@ char *number(char *buf, char *end, unsigned long long num, return buf; } +#define special_hex_spec(size) \ +(struct printf_spec) { \ + .field_width = 2 + 2 * (size), /* 0x + hex */ \ + .flags = SPECIAL | SMALL | ZEROPAD, \ + .base = 16, \ + .precision = -1, \ +} + static noinline_for_stack -char *string(char *buf, char *end, const char *s, struct printf_spec spec) +char *special_hex_number(char *buf, char *end, unsigned long long num, int size) { - int len, i; + return number(buf, end, num, special_hex_spec(size)); +} - if ((unsigned long)s < PAGE_SIZE) - s = "(null)"; +static void move_right(char *buf, char *end, unsigned len, unsigned spaces) +{ + size_t size; + if (buf >= end) /* nowhere to put anything */ + return; + size = end - buf; + if (size <= spaces) { + memset(buf, ' ', size); + return; + } + if (len) { + if (len > size - spaces) + len = size - spaces; + memmove(buf + spaces, buf, len); + } + memset(buf, ' ', spaces); +} - len = strnlen(s, spec.precision); +/* + * Handle field width padding for a string. + * @buf: current buffer position + * @n: length of string + * @end: end of output buffer + * @spec: for field width and flags + * Returns: new buffer position after padding. + */ +static noinline_for_stack +char *widen_string(char *buf, int n, char *end, struct printf_spec spec) +{ + unsigned spaces; + if (likely(n >= spec.field_width)) + return buf; + /* we want to pad the sucker */ + spaces = spec.field_width - n; if (!(spec.flags & LEFT)) { - while (len < spec.field_width--) { - if (buf < end) - *buf = ' '; - ++buf; - } + move_right(buf - n, end, n, spaces); + return buf + spaces; } - for (i = 0; i < len; ++i) { + while (spaces--) { if (buf < end) - *buf = *s; - ++buf; ++s; + *buf = ' '; + ++buf; } - while (len < spec.field_width--) { + return buf; +} + +/* Handle string from a well known address. */ +static char *string_nocheck(char *buf, char *end, const char *s, + struct printf_spec spec) +{ + int len = 0; + int lim = spec.precision; + + while (lim--) { + char c = *s++; + if (!c) + break; if (buf < end) - *buf = ' '; + *buf = c; ++buf; + ++len; } + return widen_string(buf, len, end, spec); +} + +static char *err_ptr(char *buf, char *end, void *ptr, + struct printf_spec spec) +{ + int err = PTR_ERR(ptr); + const char *sym = errname(err); + + if (sym) + return string_nocheck(buf, end, sym, spec); + /* + * Somebody passed ERR_PTR(-1234) or some other non-existing + * Efoo - or perhaps CONFIG_SYMBOLIC_ERRNAME=n. Fall back to + * printing it as its decimal representation. + */ + spec.flags |= SIGN; + spec.base = 10; + return number(buf, end, err, spec); +} + +/* Be careful: error messages must fit into the given buffer. */ +static char *error_string(char *buf, char *end, const char *s, + struct printf_spec spec) +{ + /* + * Hard limit to avoid a completely insane messages. It actually + * works pretty well because most error messages are in + * the many pointer format modifiers. + */ + if (spec.precision == -1) + spec.precision = 2 * sizeof(void *); + + return string_nocheck(buf, end, s, spec); +} + +/* + * Do not call any complex external code here. Nested printk()/vsprintf() + * might cause infinite loops. Failures might break printk() and would + * be hard to debug. + */ +static const char *check_pointer_msg(const void *ptr) +{ + if (!ptr) + return "(null)"; + + if ((unsigned long)ptr < PAGE_SIZE || IS_ERR_VALUE(ptr)) + return "(efault)"; + + return NULL; +} + +static int check_pointer(char **buf, char *end, const void *ptr, + struct printf_spec spec) +{ + const char *err_msg; + + err_msg = check_pointer_msg(ptr); + if (err_msg) { + *buf = error_string(*buf, end, err_msg, spec); + return -EFAULT; + } + + return 0; +} + +static noinline_for_stack +char *string(char *buf, char *end, const char *s, + struct printf_spec spec) +{ + if (check_pointer(&buf, end, s, spec)) + return buf; + + return string_nocheck(buf, end, s, spec); +} + +static char *pointer_string(char *buf, char *end, + const void *ptr, + struct printf_spec spec) +{ + spec.base = 16; + spec.flags |= SMALL; + if (spec.field_width == -1) { + spec.field_width = 2 * sizeof(ptr); + spec.flags |= ZEROPAD; + } + + return number(buf, end, (unsigned long int)ptr, spec); +} + +/* Make pointers available for printing early in the boot sequence. */ +static int debug_boot_weak_hash __ro_after_init; + +static int __init debug_boot_weak_hash_enable(char *str) +{ + debug_boot_weak_hash = 1; + pr_info("debug_boot_weak_hash enabled\n"); + return 0; +} +early_param("debug_boot_weak_hash", debug_boot_weak_hash_enable); + +static bool filled_random_ptr_key __read_mostly; +static siphash_key_t ptr_key __read_mostly; + +static int fill_ptr_key(struct notifier_block *nb, unsigned long action, void *data) +{ + get_random_bytes(&ptr_key, sizeof(ptr_key)); + + /* Pairs with smp_rmb() before reading ptr_key. */ + smp_wmb(); + WRITE_ONCE(filled_random_ptr_key, true); + return NOTIFY_DONE; +} + +static int __init vsprintf_init_hashval(void) +{ + static struct notifier_block fill_ptr_key_nb = { .notifier_call = fill_ptr_key }; + execute_with_initialized_rng(&fill_ptr_key_nb); + return 0; +} +subsys_initcall(vsprintf_init_hashval) + +/* Maps a pointer to a 32 bit unique identifier. */ +static inline int __ptr_to_hashval(const void *ptr, unsigned long *hashval_out) +{ + unsigned long hashval; + + if (!READ_ONCE(filled_random_ptr_key)) + return -EBUSY; + + /* Pairs with smp_wmb() after writing ptr_key. */ + smp_rmb(); + +#ifdef CONFIG_64BIT + hashval = (unsigned long)siphash_1u64((u64)ptr, &ptr_key); + /* + * Mask off the first 32 bits, this makes explicit that we have + * modified the address (and 32 bits is plenty for a unique ID). + */ + hashval = hashval & 0xffffffff; +#else + hashval = (unsigned long)siphash_1u32((u32)ptr, &ptr_key); +#endif + *hashval_out = hashval; + return 0; +} + +int ptr_to_hashval(const void *ptr, unsigned long *hashval_out) +{ + return __ptr_to_hashval(ptr, hashval_out); +} + +static char *ptr_to_id(char *buf, char *end, const void *ptr, + struct printf_spec spec) +{ + const char *str = sizeof(ptr) == 8 ? "(____ptrval____)" : "(ptrval)"; + unsigned long hashval; + int ret; + + /* + * Print the real pointer value for NULL and error pointers, + * as they are not actual addresses. + */ + if (IS_ERR_OR_NULL(ptr)) + return pointer_string(buf, end, ptr, spec); + + /* When debugging early boot use non-cryptographically secure hash. */ + if (unlikely(debug_boot_weak_hash)) { + hashval = hash_long((unsigned long)ptr, 32); + return pointer_string(buf, end, (const void *)hashval, spec); + } + + ret = __ptr_to_hashval(ptr, &hashval); + if (ret) { + spec.field_width = 2 * sizeof(ptr); + /* string length must be less than default_width */ + return error_string(buf, end, str, spec); + } + + return pointer_string(buf, end, (const void *)hashval, spec); +} + +static char *default_pointer(char *buf, char *end, const void *ptr, + struct printf_spec spec) +{ + /* + * default is to _not_ leak addresses, so hash before printing, + * unless no_hash_pointers is specified on the command line. + */ + if (unlikely(no_hash_pointers)) + return pointer_string(buf, end, ptr, spec); + + return ptr_to_id(buf, end, ptr, spec); +} + +int kptr_restrict __read_mostly; + +static noinline_for_stack +char *restricted_pointer(char *buf, char *end, const void *ptr, + struct printf_spec spec) +{ + switch (kptr_restrict) { + case 0: + /* Handle as %p, hash and do _not_ leak addresses. */ + return default_pointer(buf, end, ptr, spec); + case 1: { + const struct cred *cred; + + /* + * kptr_restrict==1 cannot be used in IRQ context + * because its test for CAP_SYSLOG would be meaningless. + */ + if (in_hardirq() || in_serving_softirq() || in_nmi()) { + if (spec.field_width == -1) + spec.field_width = 2 * sizeof(ptr); + return error_string(buf, end, "pK-error", spec); + } + + /* + * Only print the real pointer value if the current + * process has CAP_SYSLOG and is running with the + * same credentials it started with. This is because + * access to files is checked at open() time, but %pK + * checks permission at read() time. We don't want to + * leak pointer values if a binary opens a file using + * %pK and then elevates privileges before reading it. + */ + cred = current_cred(); + if (!has_capability_noaudit(current, CAP_SYSLOG) || + !uid_eq(cred->euid, cred->uid) || + !gid_eq(cred->egid, cred->gid)) + ptr = NULL; + break; + } + case 2: + default: + /* Always print 0's for %pK */ + ptr = NULL; + break; + } + + return pointer_string(buf, end, ptr, spec); +} + +static noinline_for_stack +char *dentry_name(char *buf, char *end, const struct dentry *d, struct printf_spec spec, + const char *fmt) +{ + const char *array[4], *s; + const struct dentry *p; + int depth; + int i, n; + + switch (fmt[1]) { + case '2': case '3': case '4': + depth = fmt[1] - '0'; + break; + default: + depth = 1; + } + + rcu_read_lock(); + for (i = 0; i < depth; i++, d = p) { + if (check_pointer(&buf, end, d, spec)) { + rcu_read_unlock(); + return buf; + } + + p = READ_ONCE(d->d_parent); + array[i] = READ_ONCE(d->d_name.name); + if (p == d) { + if (i) + array[i] = ""; + i++; + break; + } + } + s = array[--i]; + for (n = 0; n != spec.precision; n++, buf++) { + char c = *s++; + if (!c) { + if (!i) + break; + c = '/'; + s = array[--i]; + } + if (buf < end) + *buf = c; + } + rcu_read_unlock(); + return widen_string(buf, n, end, spec); +} + +static noinline_for_stack +char *file_dentry_name(char *buf, char *end, const struct file *f, + struct printf_spec spec, const char *fmt) +{ + if (check_pointer(&buf, end, f, spec)) + return buf; + + return dentry_name(buf, end, f->f_path.dentry, spec, fmt); +} +#ifdef CONFIG_BLOCK +static noinline_for_stack +char *bdev_name(char *buf, char *end, struct block_device *bdev, + struct printf_spec spec, const char *fmt) +{ + struct gendisk *hd; + + if (check_pointer(&buf, end, bdev, spec)) + return buf; + + hd = bdev->bd_disk; + buf = string(buf, end, hd->disk_name, spec); + if (bdev_is_partition(bdev)) { + if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) { + if (buf < end) + *buf = 'p'; + buf++; + } + buf = number(buf, end, bdev_partno(bdev), spec); + } return buf; } +#endif static noinline_for_stack char *symbol_string(char *buf, char *end, void *ptr, @@ -546,23 +1000,67 @@ char *symbol_string(char *buf, char *end, void *ptr, value = (unsigned long)ptr; #ifdef CONFIG_KALLSYMS - if (*fmt == 'B') + if (*fmt == 'B' && fmt[1] == 'b') + sprint_backtrace_build_id(sym, value); + else if (*fmt == 'B') sprint_backtrace(sym, value); - else if (*fmt != 'f' && *fmt != 's') + else if (*fmt == 'S' && (fmt[1] == 'b' || (fmt[1] == 'R' && fmt[2] == 'b'))) + sprint_symbol_build_id(sym, value); + else if (*fmt != 's') sprint_symbol(sym, value); else sprint_symbol_no_offset(sym, value); - return string(buf, end, sym, spec); + return string_nocheck(buf, end, sym, spec); #else - spec.field_width = 2 * sizeof(void *); - spec.flags |= SPECIAL | SMALL | ZEROPAD; - spec.base = 16; - - return number(buf, end, value, spec); + return special_hex_number(buf, end, value, sizeof(void *)); #endif } +static const struct printf_spec default_str_spec = { + .field_width = -1, + .precision = -1, +}; + +static const struct printf_spec default_flag_spec = { + .base = 16, + .precision = -1, + .flags = SPECIAL | SMALL, +}; + +static const struct printf_spec default_dec_spec = { + .base = 10, + .precision = -1, +}; + +static const struct printf_spec default_dec02_spec = { + .base = 10, + .field_width = 2, + .precision = -1, + .flags = ZEROPAD, +}; + +static const struct printf_spec default_dec04_spec = { + .base = 10, + .field_width = 4, + .precision = -1, + .flags = ZEROPAD, +}; + +static noinline_for_stack +char *hex_range(char *buf, char *end, u64 start_val, u64 end_val, + struct printf_spec spec) +{ + buf = number(buf, end, start_val, spec); + if (start_val == end_val) + return buf; + + if (buf < end) + *buf = '-'; + ++buf; + return number(buf, end, end_val, spec); +} + static noinline_for_stack char *resource_string(char *buf, char *end, struct resource *res, struct printf_spec spec, const char *fmt) @@ -592,21 +1090,11 @@ char *resource_string(char *buf, char *end, struct resource *res, .precision = -1, .flags = SMALL | ZEROPAD, }; - static const struct printf_spec dec_spec = { - .base = 10, - .precision = -1, - .flags = 0, - }; static const struct printf_spec str_spec = { .field_width = -1, .precision = 10, .flags = LEFT, }; - static const struct printf_spec flag_spec = { - .base = 16, - .precision = -1, - .flags = SPECIAL | SMALL, - }; /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ @@ -614,56 +1102,78 @@ char *resource_string(char *buf, char *end, struct resource *res, #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") - char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, + char sym[MAX(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; char *p = sym, *pend = sym + sizeof(sym); int decode = (fmt[0] == 'R') ? 1 : 0; const struct printf_spec *specp; + if (check_pointer(&buf, end, res, spec)) + return buf; + *p++ = '['; if (res->flags & IORESOURCE_IO) { - p = string(p, pend, "io ", str_spec); + p = string_nocheck(p, pend, "io ", str_spec); specp = &io_spec; } else if (res->flags & IORESOURCE_MEM) { - p = string(p, pend, "mem ", str_spec); + p = string_nocheck(p, pend, "mem ", str_spec); specp = &mem_spec; } else if (res->flags & IORESOURCE_IRQ) { - p = string(p, pend, "irq ", str_spec); - specp = &dec_spec; + p = string_nocheck(p, pend, "irq ", str_spec); + specp = &default_dec_spec; } else if (res->flags & IORESOURCE_DMA) { - p = string(p, pend, "dma ", str_spec); - specp = &dec_spec; + p = string_nocheck(p, pend, "dma ", str_spec); + specp = &default_dec_spec; } else if (res->flags & IORESOURCE_BUS) { - p = string(p, pend, "bus ", str_spec); + p = string_nocheck(p, pend, "bus ", str_spec); specp = &bus_spec; } else { - p = string(p, pend, "??? ", str_spec); + p = string_nocheck(p, pend, "??? ", str_spec); specp = &mem_spec; decode = 0; } - p = number(p, pend, res->start, *specp); - if (res->start != res->end) { - *p++ = '-'; - p = number(p, pend, res->end, *specp); + if (decode && res->flags & IORESOURCE_UNSET) { + p = string_nocheck(p, pend, "size ", str_spec); + p = number(p, pend, resource_size(res), *specp); + } else { + p = hex_range(p, pend, res->start, res->end, *specp); } if (decode) { if (res->flags & IORESOURCE_MEM_64) - p = string(p, pend, " 64bit", str_spec); + p = string_nocheck(p, pend, " 64bit", str_spec); if (res->flags & IORESOURCE_PREFETCH) - p = string(p, pend, " pref", str_spec); + p = string_nocheck(p, pend, " pref", str_spec); if (res->flags & IORESOURCE_WINDOW) - p = string(p, pend, " window", str_spec); + p = string_nocheck(p, pend, " window", str_spec); if (res->flags & IORESOURCE_DISABLED) - p = string(p, pend, " disabled", str_spec); + p = string_nocheck(p, pend, " disabled", str_spec); } else { - p = string(p, pend, " flags ", str_spec); - p = number(p, pend, res->flags, flag_spec); + p = string_nocheck(p, pend, " flags ", str_spec); + p = number(p, pend, res->flags, default_flag_spec); } *p++ = ']'; *p = '\0'; - return string(buf, end, sym, spec); + return string_nocheck(buf, end, sym, spec); +} + +static noinline_for_stack +char *range_string(char *buf, char *end, const struct range *range, + struct printf_spec spec, const char *fmt) +{ + char sym[sizeof("[range 0x0123456789abcdef-0x0123456789abcdef]")]; + char *p = sym, *pend = sym + sizeof(sym); + + if (check_pointer(&buf, end, range, spec)) + return buf; + + p = string_nocheck(p, pend, "[range ", default_str_spec); + p = hex_range(p, pend, range->start, range->end, special_hex_spec(sizeof(range->start))); + *p++ = ']'; + *p = '\0'; + + return string_nocheck(buf, end, sym, spec); } static noinline_for_stack @@ -678,9 +1188,8 @@ char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, /* nothing to print */ return buf; - if (ZERO_OR_NULL_PTR(addr)) - /* NULL pointer */ - return string(buf, end, NULL, spec); + if (check_pointer(&buf, end, addr, spec)) + return buf; switch (fmt[1]) { case 'C': @@ -700,13 +1209,95 @@ char *hex_string(char *buf, char *end, u8 *addr, struct printf_spec spec, if (spec.field_width > 0) len = min_t(int, spec.field_width, 64); - for (i = 0; i < len && buf < end - 1; i++) { - buf = hex_byte_pack(buf, addr[i]); + for (i = 0; i < len; ++i) { + if (buf < end) + *buf = hex_asc_hi(addr[i]); + ++buf; + if (buf < end) + *buf = hex_asc_lo(addr[i]); + ++buf; + + if (separator && i != len - 1) { + if (buf < end) + *buf = separator; + ++buf; + } + } + + return buf; +} + +static noinline_for_stack +char *bitmap_string(char *buf, char *end, const unsigned long *bitmap, + struct printf_spec spec, const char *fmt) +{ + const int CHUNKSZ = 32; + int nr_bits = max_t(int, spec.field_width, 0); + int i, chunksz; + bool first = true; + + if (check_pointer(&buf, end, bitmap, spec)) + return buf; + + /* reused to print numbers */ + spec = (struct printf_spec){ .flags = SMALL | ZEROPAD, .base = 16 }; + + chunksz = nr_bits & (CHUNKSZ - 1); + if (chunksz == 0) + chunksz = CHUNKSZ; - if (buf < end && separator && i != len - 1) - *buf++ = separator; + i = ALIGN(nr_bits, CHUNKSZ) - CHUNKSZ; + for (; i >= 0; i -= CHUNKSZ) { + u32 chunkmask, val; + int word, bit; + + chunkmask = ((1ULL << chunksz) - 1); + word = i / BITS_PER_LONG; + bit = i % BITS_PER_LONG; + val = (bitmap[word] >> bit) & chunkmask; + + if (!first) { + if (buf < end) + *buf = ','; + buf++; + } + first = false; + + spec.field_width = DIV_ROUND_UP(chunksz, 4); + buf = number(buf, end, val, spec); + + chunksz = CHUNKSZ; } + return buf; +} +static noinline_for_stack +char *bitmap_list_string(char *buf, char *end, const unsigned long *bitmap, + struct printf_spec spec, const char *fmt) +{ + int nr_bits = max_t(int, spec.field_width, 0); + bool first = true; + int rbot, rtop; + + if (check_pointer(&buf, end, bitmap, spec)) + return buf; + + for_each_set_bitrange(rbot, rtop, bitmap, nr_bits) { + if (!first) { + if (buf < end) + *buf = ','; + buf++; + } + first = false; + + buf = number(buf, end, rbot, default_dec_spec); + if (rtop == rbot + 1) + continue; + + if (buf < end) + *buf = '-'; + buf = number(++buf, end, rtop - 1, default_dec_spec); + } return buf; } @@ -720,6 +1311,9 @@ char *mac_address_string(char *buf, char *end, u8 *addr, char separator; bool reversed = false; + if (check_pointer(&buf, end, addr, spec)) + return buf; + switch (fmt[1]) { case 'F': separator = '-'; @@ -727,7 +1321,7 @@ char *mac_address_string(char *buf, char *end, u8 *addr, case 'R': reversed = true; - /* fall through */ + fallthrough; default: separator = ':'; @@ -745,7 +1339,7 @@ char *mac_address_string(char *buf, char *end, u8 *addr, } *p = '\0'; - return string(buf, end, mac_addr, spec); + return string_nocheck(buf, end, mac_addr, spec); } static noinline_for_stack @@ -778,7 +1372,7 @@ char *ip4_string(char *p, const u8 *addr, const char *fmt) break; } for (i = 0; i < 4; i++) { - char temp[3]; /* hold each IP quad in reverse order */ + char temp[4] __aligned(2); /* hold each IP quad in reverse order */ int digits = put_dec_trunc8(temp, addr[index]) - temp; if (leading_zeros) { if (digits < 3) @@ -908,7 +1502,7 @@ char *ip6_addr_string(char *buf, char *end, const u8 *addr, else ip6_string(ip6_addr, addr, fmt); - return string(buf, end, ip6_addr, spec); + return string_nocheck(buf, end, ip6_addr, spec); } static noinline_for_stack @@ -919,7 +1513,7 @@ char *ip4_addr_string(char *buf, char *end, const u8 *addr, ip4_string(ip4_addr, addr, fmt); - return string(buf, end, ip4_addr, spec); + return string_nocheck(buf, end, ip4_addr, spec); } static noinline_for_stack @@ -981,7 +1575,7 @@ char *ip6_addr_string_sa(char *buf, char *end, const struct sockaddr_in6 *sa, } *p = '\0'; - return string(buf, end, ip6_addr, spec); + return string_nocheck(buf, end, ip6_addr, spec); } static noinline_for_stack @@ -1016,26 +1610,141 @@ char *ip4_addr_string_sa(char *buf, char *end, const struct sockaddr_in *sa, } *p = '\0'; - return string(buf, end, ip4_addr, spec); + return string_nocheck(buf, end, ip4_addr, spec); +} + +static noinline_for_stack +char *ip_addr_string(char *buf, char *end, const void *ptr, + struct printf_spec spec, const char *fmt) +{ + char *err_fmt_msg; + + if (check_pointer(&buf, end, ptr, spec)) + return buf; + + switch (fmt[1]) { + case '6': + return ip6_addr_string(buf, end, ptr, spec, fmt); + case '4': + return ip4_addr_string(buf, end, ptr, spec, fmt); + case 'S': { + const union { + struct sockaddr raw; + struct sockaddr_in v4; + struct sockaddr_in6 v6; + } *sa = ptr; + + switch (sa->raw.sa_family) { + case AF_INET: + return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); + case AF_INET6: + return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); + default: + return error_string(buf, end, "(einval)", spec); + }} + } + + err_fmt_msg = fmt[0] == 'i' ? "(%pi?)" : "(%pI?)"; + return error_string(buf, end, err_fmt_msg, spec); +} + +static noinline_for_stack +char *escaped_string(char *buf, char *end, u8 *addr, struct printf_spec spec, + const char *fmt) +{ + bool found = true; + int count = 1; + unsigned int flags = 0; + int len; + + if (spec.field_width == 0) + return buf; /* nothing to print */ + + if (check_pointer(&buf, end, addr, spec)) + return buf; + + do { + switch (fmt[count++]) { + case 'a': + flags |= ESCAPE_ANY; + break; + case 'c': + flags |= ESCAPE_SPECIAL; + break; + case 'h': + flags |= ESCAPE_HEX; + break; + case 'n': + flags |= ESCAPE_NULL; + break; + case 'o': + flags |= ESCAPE_OCTAL; + break; + case 'p': + flags |= ESCAPE_NP; + break; + case 's': + flags |= ESCAPE_SPACE; + break; + default: + found = false; + break; + } + } while (found); + + if (!flags) + flags = ESCAPE_ANY_NP; + + len = spec.field_width < 0 ? 1 : spec.field_width; + + /* + * string_escape_mem() writes as many characters as it can to + * the given buffer, and returns the total size of the output + * had the buffer been big enough. + */ + buf += string_escape_mem(addr, len, buf, buf < end ? end - buf : 0, flags, NULL); + + return buf; } +__diag_push(); +__diag_ignore(GCC, all, "-Wsuggest-attribute=format", + "Not a valid __printf() conversion candidate."); +static char *va_format(char *buf, char *end, struct va_format *va_fmt, + struct printf_spec spec) +{ + va_list va; + + if (check_pointer(&buf, end, va_fmt, spec)) + return buf; + + va_copy(va, *va_fmt->va); + buf += vsnprintf(buf, end > buf ? end - buf : 0, va_fmt->fmt, va); + va_end(va); + + return buf; +} +__diag_pop(); + static noinline_for_stack char *uuid_string(char *buf, char *end, const u8 *addr, struct printf_spec spec, const char *fmt) { - char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")]; + char uuid[UUID_STRING_LEN + 1]; char *p = uuid; int i; - static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; - static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; - const u8 *index = be; + const u8 *index = uuid_index; bool uc = false; + if (check_pointer(&buf, end, addr, spec)) + return buf; + switch (*(++fmt)) { case 'L': - uc = true; /* fall-through */ + uc = true; + fallthrough; case 'l': - index = le; + index = guid_index; break; case 'B': uc = true; @@ -1043,7 +1752,10 @@ char *uuid_string(char *buf, char *end, const u8 *addr, } for (i = 0; i < 16; i++) { - p = hex_byte_pack(p, addr[index[i]]); + if (uc) + p = hex_byte_pack_upper(p, addr[index[i]]); + else + p = hex_byte_pack(p, addr[index[i]]); switch (i) { case 3: case 5: @@ -1056,45 +1768,647 @@ char *uuid_string(char *buf, char *end, const u8 *addr, *p = 0; - if (uc) { - p = uuid; - do { - *p = toupper(*p); - } while (*(++p)); + return string_nocheck(buf, end, uuid, spec); +} + +static noinline_for_stack +char *netdev_bits(char *buf, char *end, const void *addr, + struct printf_spec spec, const char *fmt) +{ + unsigned long long num; + int size; + + if (check_pointer(&buf, end, addr, spec)) + return buf; + + switch (fmt[1]) { + case 'F': + num = *(const netdev_features_t *)addr; + size = sizeof(netdev_features_t); + break; + default: + return error_string(buf, end, "(%pN?)", spec); + } + + return special_hex_number(buf, end, num, size); +} + +static noinline_for_stack +char *fourcc_string(char *buf, char *end, const u32 *fourcc, + struct printf_spec spec, const char *fmt) +{ + char output[sizeof("0123 little-endian (0x01234567)")]; + char *p = output; + unsigned int i; + bool pixel_fmt = false; + u32 orig, val; + + if (fmt[1] != 'c') + return error_string(buf, end, "(%p4?)", spec); + + if (check_pointer(&buf, end, fourcc, spec)) + return buf; + + orig = get_unaligned(fourcc); + switch (fmt[2]) { + case 'h': + if (fmt[3] == 'R') + orig = swab32(orig); + break; + case 'l': + orig = (__force u32)cpu_to_le32(orig); + break; + case 'b': + orig = (__force u32)cpu_to_be32(orig); + break; + case 'c': + /* Pixel formats are printed LSB-first */ + pixel_fmt = true; + break; + default: + return error_string(buf, end, "(%p4?)", spec); + } + + val = pixel_fmt ? swab32(orig & ~BIT(31)) : orig; + + for (i = 0; i < sizeof(u32); i++) { + unsigned char c = val >> ((3 - i) * 8); + + /* Print non-control ASCII characters as-is, dot otherwise */ + *p++ = isascii(c) && isprint(c) ? c : '.'; + } + + if (pixel_fmt) { + *p++ = ' '; + strcpy(p, orig & BIT(31) ? "big-endian" : "little-endian"); + p += strlen(p); } - return string(buf, end, uuid, spec); + *p++ = ' '; + *p++ = '('; + p = special_hex_number(p, output + sizeof(output) - 2, orig, sizeof(u32)); + *p++ = ')'; + *p = '\0'; + + return string(buf, end, output, spec); +} + +static noinline_for_stack +char *address_val(char *buf, char *end, const void *addr, + struct printf_spec spec, const char *fmt) +{ + unsigned long long num; + int size; + + if (check_pointer(&buf, end, addr, spec)) + return buf; + + switch (fmt[1]) { + case 'd': + num = *(const dma_addr_t *)addr; + size = sizeof(dma_addr_t); + break; + case 'p': + default: + num = *(const phys_addr_t *)addr; + size = sizeof(phys_addr_t); + break; + } + + return special_hex_number(buf, end, num, size); +} + +static noinline_for_stack +char *date_str(char *buf, char *end, const struct rtc_time *tm, bool r) +{ + int year = tm->tm_year + (r ? 0 : 1900); + int mon = tm->tm_mon + (r ? 0 : 1); + + buf = number(buf, end, year, default_dec04_spec); + if (buf < end) + *buf = '-'; + buf++; + + buf = number(buf, end, mon, default_dec02_spec); + if (buf < end) + *buf = '-'; + buf++; + + return number(buf, end, tm->tm_mday, default_dec02_spec); +} + +static noinline_for_stack +char *time_str(char *buf, char *end, const struct rtc_time *tm, bool r) +{ + buf = number(buf, end, tm->tm_hour, default_dec02_spec); + if (buf < end) + *buf = ':'; + buf++; + + buf = number(buf, end, tm->tm_min, default_dec02_spec); + if (buf < end) + *buf = ':'; + buf++; + + return number(buf, end, tm->tm_sec, default_dec02_spec); +} + +static noinline_for_stack +char *rtc_str(char *buf, char *end, const struct rtc_time *tm, + struct printf_spec spec, const char *fmt) +{ + bool have_t = true, have_d = true; + bool raw = false, iso8601_separator = true; + bool found = true; + int count = 2; + + switch (fmt[count]) { + case 'd': + have_t = false; + count++; + break; + case 't': + have_d = false; + count++; + break; + } + + do { + switch (fmt[count++]) { + case 'r': + raw = true; + break; + case 's': + iso8601_separator = false; + break; + default: + found = false; + break; + } + } while (found); + + if (have_d) + buf = date_str(buf, end, tm, raw); + if (have_d && have_t) { + if (buf < end) + *buf = iso8601_separator ? 'T' : ' '; + buf++; + } + if (have_t) + buf = time_str(buf, end, tm, raw); + + return buf; +} + +static noinline_for_stack +char *time64_str(char *buf, char *end, const time64_t time, + struct printf_spec spec, const char *fmt) +{ + struct rtc_time rtc_time; + struct tm tm; + + time64_to_tm(time, 0, &tm); + + rtc_time.tm_sec = tm.tm_sec; + rtc_time.tm_min = tm.tm_min; + rtc_time.tm_hour = tm.tm_hour; + rtc_time.tm_mday = tm.tm_mday; + rtc_time.tm_mon = tm.tm_mon; + rtc_time.tm_year = tm.tm_year; + rtc_time.tm_wday = tm.tm_wday; + rtc_time.tm_yday = tm.tm_yday; + + rtc_time.tm_isdst = 0; + + return rtc_str(buf, end, &rtc_time, spec, fmt); +} + +static noinline_for_stack +char *timespec64_str(char *buf, char *end, const struct timespec64 *ts, + struct printf_spec spec, const char *fmt) +{ + static const struct printf_spec default_dec09_spec = { + .base = 10, + .field_width = 9, + .precision = -1, + .flags = ZEROPAD, + }; + + if (fmt[2] == 'p') + buf = number(buf, end, ts->tv_sec, default_dec_spec); + else + buf = time64_str(buf, end, ts->tv_sec, spec, fmt); + if (buf < end) + *buf = '.'; + buf++; + + return number(buf, end, ts->tv_nsec, default_dec09_spec); +} + +static noinline_for_stack +char *time_and_date(char *buf, char *end, void *ptr, struct printf_spec spec, + const char *fmt) +{ + if (check_pointer(&buf, end, ptr, spec)) + return buf; + + switch (fmt[1]) { + case 'R': + return rtc_str(buf, end, (const struct rtc_time *)ptr, spec, fmt); + case 'S': + return timespec64_str(buf, end, (const struct timespec64 *)ptr, spec, fmt); + case 'T': + return time64_str(buf, end, *(const time64_t *)ptr, spec, fmt); + default: + return error_string(buf, end, "(%pt?)", spec); + } +} + +static noinline_for_stack +char *clock(char *buf, char *end, struct clk *clk, struct printf_spec spec, + const char *fmt) +{ + if (!IS_ENABLED(CONFIG_HAVE_CLK)) + return error_string(buf, end, "(%pC?)", spec); + + if (check_pointer(&buf, end, clk, spec)) + return buf; + +#ifdef CONFIG_COMMON_CLK + return string(buf, end, __clk_get_name(clk), spec); +#else + return ptr_to_id(buf, end, clk, spec); +#endif } static -char *netdev_feature_string(char *buf, char *end, const u8 *addr, - struct printf_spec spec) +char *format_flags(char *buf, char *end, unsigned long flags, + const struct trace_print_flags *names) { - spec.flags |= SPECIAL | SMALL | ZEROPAD; - if (spec.field_width == -1) - spec.field_width = 2 + 2 * sizeof(netdev_features_t); - spec.base = 16; + unsigned long mask; + + for ( ; flags && names->name; names++) { + mask = names->mask; + if ((flags & mask) != mask) + continue; + + buf = string(buf, end, names->name, default_str_spec); + + flags &= ~mask; + if (flags) { + if (buf < end) + *buf = '|'; + buf++; + } + } - return number(buf, end, *(const netdev_features_t *)addr, spec); + if (flags) + buf = number(buf, end, flags, default_flag_spec); + + return buf; } -int kptr_restrict __read_mostly; +struct page_flags_fields { + int width; + int shift; + int mask; + const struct printf_spec *spec; + const char *name; +}; + +static const struct page_flags_fields pff[] = { + {SECTIONS_WIDTH, SECTIONS_PGSHIFT, SECTIONS_MASK, + &default_dec_spec, "section"}, + {NODES_WIDTH, NODES_PGSHIFT, NODES_MASK, + &default_dec_spec, "node"}, + {ZONES_WIDTH, ZONES_PGSHIFT, ZONES_MASK, + &default_dec_spec, "zone"}, + {LAST_CPUPID_WIDTH, LAST_CPUPID_PGSHIFT, LAST_CPUPID_MASK, + &default_flag_spec, "lastcpupid"}, + {KASAN_TAG_WIDTH, KASAN_TAG_PGSHIFT, KASAN_TAG_MASK, + &default_flag_spec, "kasantag"}, +}; + +static +char *format_page_flags(char *buf, char *end, unsigned long flags) +{ + unsigned long main_flags = flags & PAGEFLAGS_MASK; + bool append = false; + int i; + + buf = number(buf, end, flags, default_flag_spec); + if (buf < end) + *buf = '('; + buf++; + + /* Page flags from the main area. */ + if (main_flags) { + buf = format_flags(buf, end, main_flags, pageflag_names); + append = true; + } + + /* Page flags from the fields area */ + for (i = 0; i < ARRAY_SIZE(pff); i++) { + /* Skip undefined fields. */ + if (!pff[i].width) + continue; + + /* Format: Flag Name + '=' (equals sign) + Number + '|' (separator) */ + if (append) { + if (buf < end) + *buf = '|'; + buf++; + } + + buf = string(buf, end, pff[i].name, default_str_spec); + if (buf < end) + *buf = '='; + buf++; + buf = number(buf, end, (flags >> pff[i].shift) & pff[i].mask, + *pff[i].spec); + + append = true; + } + if (buf < end) + *buf = ')'; + buf++; + + return buf; +} + +static noinline_for_stack +char *flags_string(char *buf, char *end, void *flags_ptr, + struct printf_spec spec, const char *fmt) +{ + unsigned long flags; + const struct trace_print_flags *names; + + if (check_pointer(&buf, end, flags_ptr, spec)) + return buf; + + switch (fmt[1]) { + case 'p': + return format_page_flags(buf, end, *(unsigned long *)flags_ptr); + case 'v': + flags = *(unsigned long *)flags_ptr; + names = vmaflag_names; + break; + case 'g': + flags = (__force unsigned long)(*(gfp_t *)flags_ptr); + names = gfpflag_names; + break; + default: + return error_string(buf, end, "(%pG?)", spec); + } + + return format_flags(buf, end, flags, names); +} + +static noinline_for_stack +char *fwnode_full_name_string(struct fwnode_handle *fwnode, char *buf, + char *end) +{ + int depth; + + /* Loop starting from the root node to the current node. */ + for (depth = fwnode_count_parents(fwnode); depth >= 0; depth--) { + /* + * Only get a reference for other nodes (i.e. parent nodes). + * fwnode refcount may be 0 here. + */ + struct fwnode_handle *__fwnode = depth ? + fwnode_get_nth_parent(fwnode, depth) : fwnode; + + buf = string(buf, end, fwnode_get_name_prefix(__fwnode), + default_str_spec); + buf = string(buf, end, fwnode_get_name(__fwnode), + default_str_spec); + + if (depth) + fwnode_handle_put(__fwnode); + } + + return buf; +} + +static noinline_for_stack +char *device_node_string(char *buf, char *end, struct device_node *dn, + struct printf_spec spec, const char *fmt) +{ + char tbuf[sizeof("xxxx") + 1]; + const char *p; + int ret; + char *buf_start = buf; + struct property *prop; + bool has_mult, pass; + + struct printf_spec str_spec = spec; + str_spec.field_width = -1; + + if (fmt[0] != 'F') + return error_string(buf, end, "(%pO?)", spec); + + if (!IS_ENABLED(CONFIG_OF)) + return error_string(buf, end, "(%pOF?)", spec); + + if (check_pointer(&buf, end, dn, spec)) + return buf; + + /* simple case without anything any more format specifiers */ + fmt++; + if (fmt[0] == '\0' || strcspn(fmt,"fnpPFcC") > 0) + fmt = "f"; + + for (pass = false; strspn(fmt,"fnpPFcC"); fmt++, pass = true) { + int precision; + if (pass) { + if (buf < end) + *buf = ':'; + buf++; + } + + switch (*fmt) { + case 'f': /* full_name */ + buf = fwnode_full_name_string(of_fwnode_handle(dn), buf, + end); + break; + case 'n': /* name */ + p = fwnode_get_name(of_fwnode_handle(dn)); + precision = str_spec.precision; + str_spec.precision = strchrnul(p, '@') - p; + buf = string(buf, end, p, str_spec); + str_spec.precision = precision; + break; + case 'p': /* phandle */ + buf = number(buf, end, (unsigned int)dn->phandle, default_dec_spec); + break; + case 'P': /* path-spec */ + p = fwnode_get_name(of_fwnode_handle(dn)); + if (!p[1]) + p = "/"; + buf = string(buf, end, p, str_spec); + break; + case 'F': /* flags */ + tbuf[0] = of_node_check_flag(dn, OF_DYNAMIC) ? 'D' : '-'; + tbuf[1] = of_node_check_flag(dn, OF_DETACHED) ? 'd' : '-'; + tbuf[2] = of_node_check_flag(dn, OF_POPULATED) ? 'P' : '-'; + tbuf[3] = of_node_check_flag(dn, OF_POPULATED_BUS) ? 'B' : '-'; + tbuf[4] = 0; + buf = string_nocheck(buf, end, tbuf, str_spec); + break; + case 'c': /* major compatible string */ + ret = of_property_read_string(dn, "compatible", &p); + if (!ret) + buf = string(buf, end, p, str_spec); + break; + case 'C': /* full compatible string */ + has_mult = false; + of_property_for_each_string(dn, "compatible", prop, p) { + if (has_mult) + buf = string_nocheck(buf, end, ",", str_spec); + buf = string_nocheck(buf, end, "\"", str_spec); + buf = string(buf, end, p, str_spec); + buf = string_nocheck(buf, end, "\"", str_spec); + + has_mult = true; + } + break; + default: + break; + } + } + + return widen_string(buf, buf - buf_start, end, spec); +} + +static noinline_for_stack +char *fwnode_string(char *buf, char *end, struct fwnode_handle *fwnode, + struct printf_spec spec, const char *fmt) +{ + struct printf_spec str_spec = spec; + char *buf_start = buf; + + str_spec.field_width = -1; + + if (*fmt != 'w') + return error_string(buf, end, "(%pf?)", spec); + + if (check_pointer(&buf, end, fwnode, spec)) + return buf; + + fmt++; + + switch (*fmt) { + case 'P': /* name */ + buf = string(buf, end, fwnode_get_name(fwnode), str_spec); + break; + case 'f': /* full_name */ + default: + buf = fwnode_full_name_string(fwnode, buf, end); + break; + } + + return widen_string(buf, buf - buf_start, end, spec); +} + +static noinline_for_stack +char *resource_or_range(const char *fmt, char *buf, char *end, void *ptr, + struct printf_spec spec) +{ + if (*fmt == 'r' && fmt[1] == 'a') + return range_string(buf, end, ptr, spec, fmt); + return resource_string(buf, end, ptr, spec, fmt); +} + +void __init hash_pointers_finalize(bool slub_debug) +{ + switch (hash_pointers_mode) { + case HASH_PTR_ALWAYS: + no_hash_pointers = false; + break; + case HASH_PTR_NEVER: + no_hash_pointers = true; + break; + case HASH_PTR_AUTO: + default: + no_hash_pointers = slub_debug; + break; + } + + if (!no_hash_pointers) + return; + + pr_warn("**********************************************************\n"); + pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); + pr_warn("** **\n"); + pr_warn("** This system shows unhashed kernel memory addresses **\n"); + pr_warn("** via the console, logs, and other interfaces. This **\n"); + pr_warn("** might reduce the security of your system. **\n"); + pr_warn("** **\n"); + pr_warn("** If you see this message and you are not debugging **\n"); + pr_warn("** the kernel, report this immediately to your system **\n"); + pr_warn("** administrator! **\n"); + pr_warn("** **\n"); + pr_warn("** Use hash_pointers=always to force this mode off **\n"); + pr_warn("** **\n"); + pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); + pr_warn("**********************************************************\n"); +} + +static int __init hash_pointers_mode_parse(char *str) +{ + if (!str) { + pr_warn("Hash pointers mode empty; falling back to auto.\n"); + hash_pointers_mode = HASH_PTR_AUTO; + } else if (strncmp(str, "auto", 4) == 0) { + pr_info("Hash pointers mode set to auto.\n"); + hash_pointers_mode = HASH_PTR_AUTO; + } else if (strncmp(str, "never", 5) == 0) { + pr_info("Hash pointers mode set to never.\n"); + hash_pointers_mode = HASH_PTR_NEVER; + } else if (strncmp(str, "always", 6) == 0) { + pr_info("Hash pointers mode set to always.\n"); + hash_pointers_mode = HASH_PTR_ALWAYS; + } else { + pr_warn("Unknown hash_pointers mode '%s' specified; assuming auto.\n", str); + hash_pointers_mode = HASH_PTR_AUTO; + } + + return 0; +} +early_param("hash_pointers", hash_pointers_mode_parse); + +static int __init no_hash_pointers_enable(char *str) +{ + return hash_pointers_mode_parse("never"); +} +early_param("no_hash_pointers", no_hash_pointers_enable); /* * Show a '%p' thing. A kernel extension is that the '%p' is followed * by an extra set of alphanumeric characters that are extended format * specifiers. * + * Please update scripts/checkpatch.pl when adding/removing conversion + * characters. (Search for "check for vsprintf extension"). + * * Right now we handle: * - * - 'F' For symbolic function descriptor pointers with offset - * - 'f' For simple symbolic function names without offset - * - 'S' For symbolic direct pointers with offset - * - 's' For symbolic direct pointers without offset - * - '[FfSs]R' as above with __builtin_extract_return_addr() translation + * - 'S' For symbolic direct pointers (or function descriptors) with offset + * - 's' For symbolic direct pointers (or function descriptors) without offset + * - '[Ss]R' as above with __builtin_extract_return_addr() translation + * - 'S[R]b' as above with module build ID (for use in backtraces) + * - '[Ff]' %pf and %pF were obsoleted and later removed in favor of + * %ps and %pS. Be careful when re-using these specifiers. * - 'B' For backtraced symbolic direct pointers with offset + * - 'Bb' as above with module build ID (for use in backtraces) * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] + * - 'ra' For struct ranges, e.g., [range 0x0000000000000000 - 0x00000000000000ff] + * - 'b[l]' For a bitmap, the number of bits is determined by the field + * width which must be explicitly specified either as part of the + * format string '%32b[l]' or through '%*b[l]', [l] selects + * range-list format instead of hex format * - 'M' For a 6-byte MAC address, it prints the address in the * usual colon-separated hex notation * - 'm' For a 6-byte MAC address, it prints the hex address without colons @@ -1115,7 +2429,18 @@ int kptr_restrict __read_mostly; * [4] or [6] and is able to print port [p], flowinfo [f], scope [s] * - '[Ii][4S][hnbl]' IPv4 addresses in host, network, big or little endian order * - 'I[6S]c' for IPv6 addresses printed as specified by - * http://tools.ietf.org/html/rfc5952 + * https://tools.ietf.org/html/rfc5952 + * - 'E[achnops]' For an escaped buffer, where rules are defined by combination + * of the following flags (see string_escape_mem() for the + * details): + * a - ESCAPE_ANY + * c - ESCAPE_SPECIAL + * h - ESCAPE_HEX + * n - ESCAPE_NULL + * o - ESCAPE_OCTAL + * p - ESCAPE_NP + * s - ESCAPE_SPACE + * By default ESCAPE_ANY_NP is used. * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" * Options for %pU are: @@ -1132,8 +2457,17 @@ int kptr_restrict __read_mostly; * Implements a "recursive vsnprintf". * Do not use this feature without some mechanism to verify the * correctness of the format string and va_list arguments. - * - 'K' For a kernel pointer that should be hidden from unprivileged users + * - 'K' For a kernel pointer that should be hidden from unprivileged users. + * Use only for procfs, sysfs and similar files, not printk(); please + * read the documentation (path below) first. * - 'NF' For a netdev_features_t + * - '4cc' V4L2 or DRM FourCC code, with endianness and raw numerical value. + * - '4c[h[R]lb]' For generic FourCC code with raw numerical value. Both are + * displayed in the big-endian format. This is the opposite of V4L2 or + * DRM FourCCs. + * The additional specifiers define what endianness is used to load + * the stored bytes. The data might be interpreted using the host, + * reversed host byte order, little-endian, or big-endian. * - 'h[CDN]' For a variable-length buffer, it prints it as a hex string with * a certain separator (' ' by default): * C colon @@ -1141,42 +2475,76 @@ int kptr_restrict __read_mostly; * N no separator * The maximum supported length is 64 bytes of the input. Consider * to use print_hex_dump() for the larger input. - * - 'a' For a phys_addr_t type and its derivative types (passed by reference) + * - 'a[pd]' For address types [p] phys_addr_t, [d] dma_addr_t and derivatives + * (default assumed to be phys_addr_t, passed by reference) + * - 'd[234]' For a dentry name (optionally 2-4 last components) + * - 'D[234]' Same as 'd' but for a struct file + * - 'g' For block_device name (gendisk + partition number) + * - 't[RST][dt][r][s]' For time and date as represented by: + * R struct rtc_time + * S struct timespec64 + * T time64_t + * - 'tSp' For time represented by struct timespec64 printed as <seconds>.<nanoseconds> + * - 'C' For a clock, it prints the name (Common Clock Framework) or address + * (legacy clock framework) of the clock + * - 'G' For flags to be printed as a collection of symbolic strings that would + * construct the specific value. Supported flags given by option: + * p page flags (see struct page) given as pointer to unsigned long + * g gfp flags (GFP_* and __GFP_*) given as pointer to gfp_t + * v vma flags (VM_*) given as pointer to unsigned long + * - 'OF[fnpPcCF]' For a device tree object + * Without any optional arguments prints the full_name + * f device node full_name + * n device node name + * p device node phandle + * P device node path spec (name + @unit) + * F device node flags + * c major compatible string + * C full compatible string + * - 'fw[fP]' For a firmware node (struct fwnode_handle) pointer + * Without an option prints the full name of the node + * f full name + * P node name, including a possible unit address + * - 'x' For printing the address unmodified. Equivalent to "%lx". + * Please read the documentation (path below) before using! + * - '[ku]s' For a BPF/tracing related format specifier, e.g. used out of + * bpf_trace_printk() where [ku] prefix specifies either kernel (k) + * or user (u) memory to probe, and: + * s a string, equivalent to "%s" on direct vsnprintf() use + * + * ** When making changes please also update: + * Documentation/core-api/printk-formats.rst + * + * Note: The default behaviour (unadorned %p) is to hash the address, + * rendering it useful as a unique identifier. * - * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 - * function pointers are really function descriptors, which contain a - * pointer to the real address. + * There is also a '%pA' format specifier, but it is only intended to be used + * from Rust code to format core::fmt::Arguments. Do *not* use it from C. + * See rust/kernel/print.rs for details. */ static noinline_for_stack char *pointer(const char *fmt, char *buf, char *end, void *ptr, struct printf_spec spec) { - int default_width = 2 * sizeof(void *) + (spec.flags & SPECIAL ? 2 : 0); - - if (!ptr && *fmt != 'K') { - /* - * Print (null) with the same width as a pointer so it makes - * tabular output look nice. - */ - if (spec.field_width == -1) - spec.field_width = default_width; - return string(buf, end, "(null)", spec); - } - switch (*fmt) { - case 'F': - case 'f': - ptr = dereference_function_descriptor(ptr); - /* Fallthrough */ case 'S': case 's': + ptr = dereference_symbol_descriptor(ptr); + fallthrough; case 'B': return symbol_string(buf, end, ptr, spec, fmt); case 'R': case 'r': - return resource_string(buf, end, ptr, spec, fmt); + return resource_or_range(fmt, buf, end, ptr, spec); case 'h': return hex_string(buf, end, ptr, spec, fmt); + case 'b': + switch (fmt[1]) { + case 'l': + return bitmap_list_string(buf, end, ptr, spec, fmt); + default: + return bitmap_string(buf, end, ptr, spec, fmt); + } case 'M': /* Colon separated: 00:01:02:03:04:05 */ case 'm': /* Contiguous: 000102030405 */ /* [mM]F (FDDI) */ @@ -1191,77 +2559,84 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, * 4: 001.002.003.004 * 6: 000102...0f */ - switch (fmt[1]) { - case '6': - return ip6_addr_string(buf, end, ptr, spec, fmt); - case '4': - return ip4_addr_string(buf, end, ptr, spec, fmt); - case 'S': { - const union { - struct sockaddr raw; - struct sockaddr_in v4; - struct sockaddr_in6 v6; - } *sa = ptr; - - switch (sa->raw.sa_family) { - case AF_INET: - return ip4_addr_string_sa(buf, end, &sa->v4, spec, fmt); - case AF_INET6: - return ip6_addr_string_sa(buf, end, &sa->v6, spec, fmt); - default: - return string(buf, end, "(invalid address)", spec); - }} - } - break; + return ip_addr_string(buf, end, ptr, spec, fmt); + case 'E': + return escaped_string(buf, end, ptr, spec, fmt); case 'U': return uuid_string(buf, end, ptr, spec, fmt); case 'V': - { - va_list va; - - va_copy(va, *((struct va_format *)ptr)->va); - buf += vsnprintf(buf, end > buf ? end - buf : 0, - ((struct va_format *)ptr)->fmt, va); - va_end(va); - return buf; - } + return va_format(buf, end, ptr, spec); case 'K': - /* - * %pK cannot be used in IRQ context because its test - * for CAP_SYSLOG would be meaningless. - */ - if (kptr_restrict && (in_irq() || in_serving_softirq() || - in_nmi())) { - if (spec.field_width == -1) - spec.field_width = default_width; - return string(buf, end, "pK-error", spec); - } - if (!((kptr_restrict == 0) || - (kptr_restrict == 1 && - has_capability_noaudit(current, CAP_SYSLOG)))) - ptr = NULL; - break; + return restricted_pointer(buf, end, ptr, spec); case 'N': + return netdev_bits(buf, end, ptr, spec, fmt); + case '4': + return fourcc_string(buf, end, ptr, spec, fmt); + case 'a': + return address_val(buf, end, ptr, spec, fmt); + case 'd': + return dentry_name(buf, end, ptr, spec, fmt); + case 't': + return time_and_date(buf, end, ptr, spec, fmt); + case 'C': + return clock(buf, end, ptr, spec, fmt); + case 'D': + return file_dentry_name(buf, end, ptr, spec, fmt); +#ifdef CONFIG_BLOCK + case 'g': + return bdev_name(buf, end, ptr, spec, fmt); +#endif + + case 'G': + return flags_string(buf, end, ptr, spec, fmt); + case 'O': + return device_node_string(buf, end, ptr, spec, fmt + 1); + case 'f': + return fwnode_string(buf, end, ptr, spec, fmt + 1); + case 'A': + if (!IS_ENABLED(CONFIG_RUST)) { + WARN_ONCE(1, "Please remove %%pA from non-Rust code\n"); + return error_string(buf, end, "(%pA?)", spec); + } + return rust_fmt_argument(buf, end, ptr); + case 'x': + return pointer_string(buf, end, ptr, spec); + case 'e': + /* %pe with a non-ERR_PTR gets treated as plain %p */ + if (!IS_ERR(ptr)) + return default_pointer(buf, end, ptr, spec); + return err_ptr(buf, end, ptr, spec); + case 'u': + case 'k': switch (fmt[1]) { - case 'F': - return netdev_feature_string(buf, end, ptr, spec); + case 's': + return string(buf, end, ptr, spec); + default: + return error_string(buf, end, "(einval)", spec); } - break; - case 'a': - spec.flags |= SPECIAL | SMALL | ZEROPAD; - spec.field_width = sizeof(phys_addr_t) * 2 + 2; - spec.base = 16; - return number(buf, end, - (unsigned long long) *((phys_addr_t *)ptr), spec); - } - spec.flags |= SMALL; - if (spec.field_width == -1) { - spec.field_width = default_width; - spec.flags |= ZEROPAD; + default: + return default_pointer(buf, end, ptr, spec); } - spec.base = 16; +} - return number(buf, end, (unsigned long) ptr, spec); +struct fmt { + const char *str; + unsigned char state; // enum format_state + unsigned char size; // size of numbers +}; + +#define SPEC_CHAR(x, flag) [(x)-32] = flag +static unsigned char spec_flag(unsigned char c) +{ + static const unsigned char spec_flag_array[] = { + SPEC_CHAR(' ', SPACE), + SPEC_CHAR('#', SPECIAL), + SPEC_CHAR('+', PLUS), + SPEC_CHAR('-', LEFT), + SPEC_CHAR('0', ZEROPAD), + }; + c -= 32; + return (c < sizeof(spec_flag_array)) ? spec_flag_array[c] : 0; } /* @@ -1274,6 +2649,7 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, * 'h', 'l', or 'L' for integer fields * 'z' support added 23/7/1999 S.H. * 'z' changed to 'Z' --davidm 1/25/99 + * 'Z' changed to 'z' --adobriyan 2017-01-25 * 't' added for ptrdiff_t * * @fmt: the format string @@ -1285,218 +2661,194 @@ char *pointer(const char *fmt, char *buf, char *end, void *ptr, * @qualifier: qualifier of a number (long, size_t, ...) */ static noinline_for_stack -int format_decode(const char *fmt, struct printf_spec *spec) +struct fmt format_decode(struct fmt fmt, struct printf_spec *spec) { - const char *start = fmt; + const char *start = fmt.str; + char flag; /* we finished early by reading the field width */ - if (spec->type == FORMAT_TYPE_WIDTH) { + if (unlikely(fmt.state == FORMAT_STATE_WIDTH)) { if (spec->field_width < 0) { spec->field_width = -spec->field_width; spec->flags |= LEFT; } - spec->type = FORMAT_TYPE_NONE; + fmt.state = FORMAT_STATE_NONE; goto precision; } /* we finished early by reading the precision */ - if (spec->type == FORMAT_TYPE_PRECISION) { + if (unlikely(fmt.state == FORMAT_STATE_PRECISION)) { if (spec->precision < 0) spec->precision = 0; - spec->type = FORMAT_TYPE_NONE; + fmt.state = FORMAT_STATE_NONE; goto qualifier; } /* By default */ - spec->type = FORMAT_TYPE_NONE; + fmt.state = FORMAT_STATE_NONE; - for (; *fmt ; ++fmt) { - if (*fmt == '%') + for (; *fmt.str ; fmt.str++) { + if (*fmt.str == '%') break; } /* Return the current non-format string */ - if (fmt != start || !*fmt) - return fmt - start; + if (fmt.str != start || !*fmt.str) + return fmt; - /* Process flags */ + /* Process flags. This also skips the first '%' */ spec->flags = 0; - - while (1) { /* this also skips first '%' */ - bool found = true; - - ++fmt; - - switch (*fmt) { - case '-': spec->flags |= LEFT; break; - case '+': spec->flags |= PLUS; break; - case ' ': spec->flags |= SPACE; break; - case '#': spec->flags |= SPECIAL; break; - case '0': spec->flags |= ZEROPAD; break; - default: found = false; - } - - if (!found) - break; - } + do { + /* this also skips first '%' */ + flag = spec_flag(*++fmt.str); + spec->flags |= flag; + } while (flag); /* get field width */ spec->field_width = -1; - if (isdigit(*fmt)) - spec->field_width = skip_atoi(&fmt); - else if (*fmt == '*') { + if (isdigit(*fmt.str)) + spec->field_width = skip_atoi(&fmt.str); + else if (unlikely(*fmt.str == '*')) { /* it's the next argument */ - spec->type = FORMAT_TYPE_WIDTH; - return ++fmt - start; + fmt.state = FORMAT_STATE_WIDTH; + fmt.str++; + return fmt; } precision: /* get the precision */ spec->precision = -1; - if (*fmt == '.') { - ++fmt; - if (isdigit(*fmt)) { - spec->precision = skip_atoi(&fmt); + if (unlikely(*fmt.str == '.')) { + fmt.str++; + if (isdigit(*fmt.str)) { + spec->precision = skip_atoi(&fmt.str); if (spec->precision < 0) spec->precision = 0; - } else if (*fmt == '*') { + } else if (*fmt.str == '*') { /* it's the next argument */ - spec->type = FORMAT_TYPE_PRECISION; - return ++fmt - start; + fmt.state = FORMAT_STATE_PRECISION; + fmt.str++; + return fmt; } } qualifier: - /* get the conversion qualifier */ - spec->qualifier = -1; - if (*fmt == 'h' || _tolower(*fmt) == 'l' || - _tolower(*fmt) == 'z' || *fmt == 't') { - spec->qualifier = *fmt++; - if (unlikely(spec->qualifier == *fmt)) { - if (spec->qualifier == 'l') { - spec->qualifier = 'L'; - ++fmt; - } else if (spec->qualifier == 'h') { - spec->qualifier = 'H'; - ++fmt; - } - } - } - - /* default base */ + /* Set up default numeric format */ spec->base = 10; - switch (*fmt) { - case 'c': - spec->type = FORMAT_TYPE_CHAR; - return ++fmt - start; - - case 's': - spec->type = FORMAT_TYPE_STR; - return ++fmt - start; - - case 'p': - spec->type = FORMAT_TYPE_PTR; - return fmt - start; - /* skip alnum */ + fmt.state = FORMAT_STATE_NUM; + fmt.size = sizeof(int); + static const struct format_state { + unsigned char state; + unsigned char size; + unsigned char flags_or_double_size; + unsigned char base; + } lookup_state[256] = { + // Length + ['l'] = { 0, sizeof(long), sizeof(long long) }, + ['L'] = { 0, sizeof(long long) }, + ['h'] = { 0, sizeof(short), sizeof(char) }, + ['H'] = { 0, sizeof(char) }, // Questionable historical + ['z'] = { 0, sizeof(size_t) }, + ['t'] = { 0, sizeof(ptrdiff_t) }, + + // Non-numeric formats + ['c'] = { FORMAT_STATE_CHAR }, + ['s'] = { FORMAT_STATE_STR }, + ['p'] = { FORMAT_STATE_PTR }, + ['%'] = { FORMAT_STATE_PERCENT_CHAR }, + + // Numerics + ['o'] = { FORMAT_STATE_NUM, 0, 0, 8 }, + ['x'] = { FORMAT_STATE_NUM, 0, SMALL, 16 }, + ['X'] = { FORMAT_STATE_NUM, 0, 0, 16 }, + ['d'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, + ['i'] = { FORMAT_STATE_NUM, 0, SIGN, 10 }, + ['u'] = { FORMAT_STATE_NUM, 0, 0, 10, }, - case 'n': - spec->type = FORMAT_TYPE_NRCHARS; - return ++fmt - start; - - case '%': - spec->type = FORMAT_TYPE_PERCENT_CHAR; - return ++fmt - start; - - /* integer number formats - set up the flags and "break" */ - case 'o': - spec->base = 8; - break; - - case 'x': - spec->flags |= SMALL; + /* + * Since %n poses a greater security risk than + * utility, treat it as any other invalid or + * unsupported format specifier. + */ + }; - case 'X': - spec->base = 16; - break; + const struct format_state *p = lookup_state + (u8)*fmt.str; + if (p->size) { + fmt.size = p->size; + if (p->flags_or_double_size && fmt.str[0] == fmt.str[1]) { + fmt.size = p->flags_or_double_size; + fmt.str++; + } + fmt.str++; + p = lookup_state + *fmt.str; + } + if (p->state) { + if (p->base) + spec->base = p->base; + spec->flags |= p->flags_or_double_size; + fmt.state = p->state; + fmt.str++; + return fmt; + } - case 'd': - case 'i': - spec->flags |= SIGN; - case 'u': - break; + WARN_ONCE(1, "Please remove unsupported %%%c in format string\n", *fmt.str); + fmt.state = FORMAT_STATE_INVALID; + return fmt; +} - default: - spec->type = FORMAT_TYPE_INVALID; - return fmt - start; +static void +set_field_width(struct printf_spec *spec, int width) +{ + spec->field_width = width; + if (WARN_ONCE(spec->field_width != width, "field width %d too large", width)) { + spec->field_width = clamp(width, -FIELD_WIDTH_MAX, FIELD_WIDTH_MAX); } +} - if (spec->qualifier == 'L') - spec->type = FORMAT_TYPE_LONG_LONG; - else if (spec->qualifier == 'l') { - if (spec->flags & SIGN) - spec->type = FORMAT_TYPE_LONG; - else - spec->type = FORMAT_TYPE_ULONG; - } else if (_tolower(spec->qualifier) == 'z') { - spec->type = FORMAT_TYPE_SIZE_T; - } else if (spec->qualifier == 't') { - spec->type = FORMAT_TYPE_PTRDIFF; - } else if (spec->qualifier == 'H') { - if (spec->flags & SIGN) - spec->type = FORMAT_TYPE_BYTE; - else - spec->type = FORMAT_TYPE_UBYTE; - } else if (spec->qualifier == 'h') { - if (spec->flags & SIGN) - spec->type = FORMAT_TYPE_SHORT; - else - spec->type = FORMAT_TYPE_USHORT; - } else { - if (spec->flags & SIGN) - spec->type = FORMAT_TYPE_INT; - else - spec->type = FORMAT_TYPE_UINT; +static void +set_precision(struct printf_spec *spec, int prec) +{ + spec->precision = prec; + if (WARN_ONCE(spec->precision != prec, "precision %d too large", prec)) { + spec->precision = clamp(prec, 0, PRECISION_MAX); } +} + +/* + * Turn a 1/2/4-byte value into a 64-bit one for printing: truncate + * as necessary and deal with signedness. + * + * 'size' is the size of the value in bytes. + */ +static unsigned long long convert_num_spec(unsigned int val, int size, struct printf_spec spec) +{ + unsigned int shift = 32 - size*8; - return ++fmt - start; + val <<= shift; + if (!(spec.flags & SIGN)) + return val >> shift; + return (int)val >> shift; } /** * vsnprintf - Format a string and place it in a buffer * @buf: The buffer to place the result into * @size: The size of the buffer, including the trailing null space - * @fmt: The format string to use + * @fmt_str: The format string to use * @args: Arguments for the format string * - * This function follows C99 vsnprintf, but has some extensions: - * %pS output the name of a text symbol with offset - * %ps output the name of a text symbol without offset - * %pF output the name of a function pointer with its offset - * %pf output the name of a function pointer without its offset - * %pB output the name of a backtrace symbol with its offset - * %pR output the address range in a struct resource with decoded flags - * %pr output the address range in a struct resource with raw flags - * %pM output a 6-byte MAC address with colons - * %pMR output a 6-byte MAC address with colons in reversed order - * %pMF output a 6-byte MAC address with dashes - * %pm output a 6-byte MAC address without colons - * %pmR output a 6-byte MAC address without colons in reversed order - * %pI4 print an IPv4 address without leading zeros - * %pi4 print an IPv4 address with leading zeros - * %pI6 print an IPv6 address with colons - * %pi6 print an IPv6 address without colons - * %pI6c print an IPv6 address as specified by RFC 5952 - * %pIS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address - * %piS depending on sa_family of 'struct sockaddr *' print IPv4/IPv6 address - * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper - * case. - * %*ph[CDN] a variable-length hex string with a separator (supports up to 64 - * bytes of the input) - * %n is ignored + * This function generally follows C99 vsnprintf, but has some + * extensions and a few limitations: * - * ** Please update Documentation/printk-formats.txt when making changes ** + * - ``%n`` is unsupported + * - ``%p*`` is handled by pointer() + * + * See pointer() or Documentation/core-api/printk-formats.rst for more + * extensive description. + * + * **Please update the documentation in both places when making changes** * * The return value is the number of characters which would * be generated for the given input, excluding the trailing @@ -1508,15 +2860,18 @@ qualifier: * * If you're not already dealing with a va_list consider using snprintf(). */ -int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) +int vsnprintf(char *buf, size_t size, const char *fmt_str, va_list args) { - unsigned long long num; char *str, *end; struct printf_spec spec = {0}; + struct fmt fmt = { + .str = fmt_str, + .state = FORMAT_STATE_NONE, + }; /* Reject out-of-range values early. Large positive sizes are used for unknown buffer sizes. */ - if (WARN_ON_ONCE((int) size < 0)) + if (WARN_ON_ONCE(size > INT_MAX)) return 0; str = buf; @@ -1528,33 +2883,44 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) size = end - buf; } - while (*fmt) { - const char *old_fmt = fmt; - int read = format_decode(fmt, &spec); + while (*fmt.str) { + const char *old_fmt = fmt.str; - fmt += read; + fmt = format_decode(fmt, &spec); - switch (spec.type) { - case FORMAT_TYPE_NONE: { - int copy = read; + switch (fmt.state) { + case FORMAT_STATE_NONE: { + int read = fmt.str - old_fmt; if (str < end) { + int copy = read; if (copy > end - str) copy = end - str; memcpy(str, old_fmt, copy); } str += read; - break; + continue; } - case FORMAT_TYPE_WIDTH: - spec.field_width = va_arg(args, int); - break; + case FORMAT_STATE_NUM: { + unsigned long long num; - case FORMAT_TYPE_PRECISION: - spec.precision = va_arg(args, int); - break; + if (fmt.size > sizeof(int)) + num = va_arg(args, long long); + else + num = convert_num_spec(va_arg(args, int), fmt.size, spec); + str = number(str, end, num, spec); + continue; + } + + case FORMAT_STATE_WIDTH: + set_field_width(&spec, va_arg(args, int)); + continue; + + case FORMAT_STATE_PRECISION: + set_precision(&spec, va_arg(args, int)); + continue; - case FORMAT_TYPE_CHAR: { + case FORMAT_STATE_CHAR: { char c; if (!(spec.flags & LEFT)) { @@ -1574,91 +2940,40 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) *str = ' '; ++str; } - break; + continue; } - case FORMAT_TYPE_STR: + case FORMAT_STATE_STR: str = string(str, end, va_arg(args, char *), spec); - break; + continue; - case FORMAT_TYPE_PTR: - str = pointer(fmt+1, str, end, va_arg(args, void *), + case FORMAT_STATE_PTR: + str = pointer(fmt.str, str, end, va_arg(args, void *), spec); - while (isalnum(*fmt)) - fmt++; - break; - - case FORMAT_TYPE_PERCENT_CHAR: - if (str < end) - *str = '%'; - ++str; - break; + while (isalnum(*fmt.str)) + fmt.str++; + continue; - case FORMAT_TYPE_INVALID: + case FORMAT_STATE_PERCENT_CHAR: if (str < end) *str = '%'; ++str; - break; - - case FORMAT_TYPE_NRCHARS: { - u8 qualifier = spec.qualifier; - - if (qualifier == 'l') { - long *ip = va_arg(args, long *); - *ip = (str - buf); - } else if (_tolower(qualifier) == 'z') { - size_t *ip = va_arg(args, size_t *); - *ip = (str - buf); - } else { - int *ip = va_arg(args, int *); - *ip = (str - buf); - } - break; - } + continue; default: - switch (spec.type) { - case FORMAT_TYPE_LONG_LONG: - num = va_arg(args, long long); - break; - case FORMAT_TYPE_ULONG: - num = va_arg(args, unsigned long); - break; - case FORMAT_TYPE_LONG: - num = va_arg(args, long); - break; - case FORMAT_TYPE_SIZE_T: - if (spec.flags & SIGN) - num = va_arg(args, ssize_t); - else - num = va_arg(args, size_t); - break; - case FORMAT_TYPE_PTRDIFF: - num = va_arg(args, ptrdiff_t); - break; - case FORMAT_TYPE_UBYTE: - num = (unsigned char) va_arg(args, int); - break; - case FORMAT_TYPE_BYTE: - num = (signed char) va_arg(args, int); - break; - case FORMAT_TYPE_USHORT: - num = (unsigned short) va_arg(args, int); - break; - case FORMAT_TYPE_SHORT: - num = (short) va_arg(args, int); - break; - case FORMAT_TYPE_INT: - num = (int) va_arg(args, int); - break; - default: - num = va_arg(args, unsigned int); - } - - str = number(str, end, num, spec); + /* + * Presumably the arguments passed gcc's type + * checking, but there is no safe or sane way + * for us to continue parsing the format and + * fetching from the va_list; the remaining + * specifiers and arguments would be out of + * sync. + */ + goto out; } } +out: if (size > 0) { if (str < end) *str = '\0'; @@ -1691,13 +3006,15 @@ int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) { int i; + if (unlikely(!size)) + return 0; + i = vsnprintf(buf, size, fmt, args); if (likely(i < size)) return i; - if (size != 0) - return size - 1; - return 0; + + return size - 1; } EXPORT_SYMBOL(vscnprintf); @@ -1758,8 +3075,8 @@ EXPORT_SYMBOL(scnprintf); * @fmt: The format string to use * @args: Arguments for the format string * - * The function returns the number of characters written - * into @buf. Use vsnprintf() or vscnprintf() in order to avoid + * The return value is the number of characters written into @buf not including + * the trailing '\0'. Use vsnprintf() or vscnprintf() in order to avoid * buffer overflows. * * If you're not already dealing with a va_list consider using sprintf(). @@ -1778,8 +3095,8 @@ EXPORT_SYMBOL(vsprintf); * @fmt: The format string to use * @...: Arguments for the format string * - * The function returns the number of characters written - * into @buf. Use snprintf() or scnprintf() in order to avoid + * The return value is the number of characters written into @buf not including + * the trailing '\0'. Use snprintf() or scnprintf() in order to avoid * buffer overflows. * * See the vsnprintf() documentation for format string extensions over C99. @@ -1808,11 +3125,11 @@ EXPORT_SYMBOL(sprintf); * vbin_printf - Parse a format string and place args' binary value in a buffer * @bin_buf: The buffer to place args' binary value * @size: The size of the buffer(by words(32bits), not characters) - * @fmt: The format string to use + * @fmt_str: The format string to use * @args: Arguments for the format string * * The format follows C99 vsnprintf, except %n is ignored, and its argument - * is skiped. + * is skipped. * * The return value is the number of words(32bits) which would be generated for * the given input. @@ -1821,61 +3138,74 @@ EXPORT_SYMBOL(sprintf); * If the return value is greater than @size, the resulting bin_buf is NOT * valid for bstr_printf(). */ -int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) +int vbin_printf(u32 *bin_buf, size_t size, const char *fmt_str, va_list args) { + struct fmt fmt = { + .str = fmt_str, + .state = FORMAT_STATE_NONE, + }; struct printf_spec spec = {0}; char *str, *end; + int width; str = (char *)bin_buf; end = (char *)(bin_buf + size); #define save_arg(type) \ -do { \ +({ \ + unsigned long long value; \ if (sizeof(type) == 8) { \ - unsigned long long value; \ + unsigned long long val8; \ str = PTR_ALIGN(str, sizeof(u32)); \ - value = va_arg(args, unsigned long long); \ + val8 = va_arg(args, unsigned long long); \ if (str + sizeof(type) <= end) { \ - *(u32 *)str = *(u32 *)&value; \ - *(u32 *)(str + 4) = *((u32 *)&value + 1); \ + *(u32 *)str = *(u32 *)&val8; \ + *(u32 *)(str + 4) = *((u32 *)&val8 + 1); \ } \ + value = val8; \ } else { \ - unsigned long value; \ + unsigned int val4; \ str = PTR_ALIGN(str, sizeof(type)); \ - value = va_arg(args, int); \ + val4 = va_arg(args, int); \ if (str + sizeof(type) <= end) \ - *(typeof(type) *)str = (type)value; \ + *(typeof(type) *)str = (type)(long)val4; \ + value = (unsigned long long)val4; \ } \ str += sizeof(type); \ -} while (0) - - while (*fmt) { - int read = format_decode(fmt, &spec); + value; \ +}) - fmt += read; + while (*fmt.str) { + fmt = format_decode(fmt, &spec); - switch (spec.type) { - case FORMAT_TYPE_NONE: - case FORMAT_TYPE_INVALID: - case FORMAT_TYPE_PERCENT_CHAR: + switch (fmt.state) { + case FORMAT_STATE_NONE: + case FORMAT_STATE_PERCENT_CHAR: break; - - case FORMAT_TYPE_WIDTH: - case FORMAT_TYPE_PRECISION: - save_arg(int); + case FORMAT_STATE_INVALID: + goto out; + + case FORMAT_STATE_WIDTH: + case FORMAT_STATE_PRECISION: + width = (int)save_arg(int); + /* Pointers may require the width */ + if (*fmt.str == 'p') + set_field_width(&spec, width); break; - case FORMAT_TYPE_CHAR: + case FORMAT_STATE_CHAR: save_arg(char); break; - case FORMAT_TYPE_STR: { + case FORMAT_STATE_STR: { const char *save_str = va_arg(args, char *); + const char *err_msg; size_t len; - if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE - || (unsigned long)save_str < PAGE_SIZE) - save_str = "(null)"; + err_msg = check_pointer_msg(save_str); + if (err_msg) + save_str = err_msg; + len = strlen(save_str) + 1; if (str + len < end) memcpy(str, save_str, len); @@ -1883,56 +3213,44 @@ do { \ break; } - case FORMAT_TYPE_PTR: - save_arg(void *); + case FORMAT_STATE_PTR: + /* Dereferenced pointers must be done now */ + switch (*fmt.str) { + /* Dereference of functions is still OK */ + case 'S': + case 's': + case 'x': + case 'K': + case 'e': + save_arg(void *); + break; + default: + if (!isalnum(*fmt.str)) { + save_arg(void *); + break; + } + str = pointer(fmt.str, str, end, va_arg(args, void *), + spec); + if (str + 1 < end) + *str++ = '\0'; + else + end[-1] = '\0'; /* Must be nul terminated */ + } /* skip all alphanumeric pointer suffixes */ - while (isalnum(*fmt)) - fmt++; - break; - - case FORMAT_TYPE_NRCHARS: { - /* skip %n 's argument */ - u8 qualifier = spec.qualifier; - void *skip_arg; - if (qualifier == 'l') - skip_arg = va_arg(args, long *); - else if (_tolower(qualifier) == 'z') - skip_arg = va_arg(args, size_t *); - else - skip_arg = va_arg(args, int *); + while (isalnum(*fmt.str)) + fmt.str++; break; - } - - default: - switch (spec.type) { - case FORMAT_TYPE_LONG_LONG: + case FORMAT_STATE_NUM: + if (fmt.size > sizeof(int)) { save_arg(long long); - break; - case FORMAT_TYPE_ULONG: - case FORMAT_TYPE_LONG: - save_arg(unsigned long); - break; - case FORMAT_TYPE_SIZE_T: - save_arg(size_t); - break; - case FORMAT_TYPE_PTRDIFF: - save_arg(ptrdiff_t); - break; - case FORMAT_TYPE_UBYTE: - case FORMAT_TYPE_BYTE: - save_arg(char); - break; - case FORMAT_TYPE_USHORT: - case FORMAT_TYPE_SHORT: - save_arg(short); - break; - default: + } else { save_arg(int); } } } +out: return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; #undef save_arg } @@ -1942,7 +3260,7 @@ EXPORT_SYMBOL_GPL(vbin_printf); * bstr_printf - Format a string from binary arguments and place it in a buffer * @buf: The buffer to place the result into * @size: The size of the buffer, including the trailing null space - * @fmt: The format string to use + * @fmt_str: The format string to use * @bin_buf: Binary arguments for the format string * * This function like C99 vsnprintf, but the difference is that vsnprintf gets @@ -1960,13 +3278,17 @@ EXPORT_SYMBOL_GPL(vbin_printf); * return is greater than or equal to @size, the resulting * string is truncated. */ -int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) +int bstr_printf(char *buf, size_t size, const char *fmt_str, const u32 *bin_buf) { + struct fmt fmt = { + .str = fmt_str, + .state = FORMAT_STATE_NONE, + }; struct printf_spec spec = {0}; char *str, *end; const char *args = (const char *)bin_buf; - if (WARN_ON_ONCE((int) size < 0)) + if (WARN_ON_ONCE(size > INT_MAX)) return 0; str = buf; @@ -1993,33 +3315,33 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) size = end - buf; } - while (*fmt) { - const char *old_fmt = fmt; - int read = format_decode(fmt, &spec); - - fmt += read; + while (*fmt.str) { + const char *old_fmt = fmt.str; + unsigned long long num; - switch (spec.type) { - case FORMAT_TYPE_NONE: { - int copy = read; + fmt = format_decode(fmt, &spec); + switch (fmt.state) { + case FORMAT_STATE_NONE: { + int read = fmt.str - old_fmt; if (str < end) { + int copy = read; if (copy > end - str) copy = end - str; memcpy(str, old_fmt, copy); } str += read; - break; + continue; } - case FORMAT_TYPE_WIDTH: - spec.field_width = get_arg(int); - break; + case FORMAT_STATE_WIDTH: + set_field_width(&spec, get_arg(int)); + continue; - case FORMAT_TYPE_PRECISION: - spec.precision = get_arg(int); - break; + case FORMAT_STATE_PRECISION: + set_precision(&spec, get_arg(int)); + continue; - case FORMAT_TYPE_CHAR: { + case FORMAT_STATE_CHAR: { char c; if (!(spec.flags & LEFT)) { @@ -2038,75 +3360,71 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) *str = ' '; ++str; } - break; + continue; } - case FORMAT_TYPE_STR: { + case FORMAT_STATE_STR: { const char *str_arg = args; args += strlen(str_arg) + 1; str = string(str, end, (char *)str_arg, spec); - break; + continue; } - case FORMAT_TYPE_PTR: - str = pointer(fmt+1, str, end, get_arg(void *), spec); - while (isalnum(*fmt)) - fmt++; - break; + case FORMAT_STATE_PTR: { + bool process = false; + int copy, len; + /* Non function dereferences were already done */ + switch (*fmt.str) { + case 'S': + case 's': + case 'x': + case 'K': + case 'e': + process = true; + break; + default: + if (!isalnum(*fmt.str)) { + process = true; + break; + } + /* Pointer dereference was already processed */ + if (str < end) { + len = copy = strlen(args); + if (copy > end - str) + copy = end - str; + memcpy(str, args, copy); + str += len; + args += len + 1; + } + } + if (process) + str = pointer(fmt.str, str, end, get_arg(void *), spec); + + while (isalnum(*fmt.str)) + fmt.str++; + continue; + } - case FORMAT_TYPE_PERCENT_CHAR: - case FORMAT_TYPE_INVALID: + case FORMAT_STATE_PERCENT_CHAR: if (str < end) *str = '%'; ++str; - break; - - case FORMAT_TYPE_NRCHARS: - /* skip */ - break; - - default: { - unsigned long long num; + continue; - switch (spec.type) { + case FORMAT_STATE_INVALID: + goto out; - case FORMAT_TYPE_LONG_LONG: + case FORMAT_STATE_NUM: + if (fmt.size > sizeof(int)) num = get_arg(long long); - break; - case FORMAT_TYPE_ULONG: - case FORMAT_TYPE_LONG: - num = get_arg(unsigned long); - break; - case FORMAT_TYPE_SIZE_T: - num = get_arg(size_t); - break; - case FORMAT_TYPE_PTRDIFF: - num = get_arg(ptrdiff_t); - break; - case FORMAT_TYPE_UBYTE: - num = get_arg(unsigned char); - break; - case FORMAT_TYPE_BYTE: - num = get_arg(signed char); - break; - case FORMAT_TYPE_USHORT: - num = get_arg(unsigned short); - break; - case FORMAT_TYPE_SHORT: - num = get_arg(short); - break; - case FORMAT_TYPE_UINT: - num = get_arg(unsigned int); - break; - default: - num = get_arg(int); - } - + else + num = convert_num_spec(get_arg(int), fmt.size, spec); str = number(str, end, num, spec); - } /* default: */ - } /* switch(spec.type) */ - } /* while(*fmt) */ + continue; + } + } /* while(*fmt.str) */ +out: if (size > 0) { if (str < end) *str = '\0'; @@ -2121,29 +3439,6 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) } EXPORT_SYMBOL_GPL(bstr_printf); -/** - * bprintf - Parse a format string and place args' binary value in a buffer - * @bin_buf: The buffer to place args' binary value - * @size: The size of the buffer(by words(32bits), not characters) - * @fmt: The format string to use - * @...: Arguments for the format string - * - * The function returns the number of words(u32) written - * into @bin_buf. - */ -int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) -{ - va_list args; - int ret; - - va_start(args, fmt); - ret = vbin_printf(bin_buf, size, fmt, args); - va_end(args); - - return ret; -} -EXPORT_SYMBOL_GPL(bprintf); - #endif /* CONFIG_BINARY_PRINTF */ /** @@ -2169,7 +3464,7 @@ int vsscanf(const char *buf, const char *fmt, va_list args) while (*fmt) { /* skip any white space in format */ - /* white space in format matchs any amount of + /* white space in format matches any amount of * white space, including none, in the input. */ if (isspace(*fmt)) { @@ -2194,8 +3489,12 @@ int vsscanf(const char *buf, const char *fmt, va_list args) if (*fmt == '*') { if (!*str) break; - while (!isspace(*fmt) && *fmt != '%' && *fmt) + while (!isspace(*fmt) && *fmt != '%' && *fmt) { + /* '%*[' not yet supported, invalid format */ + if (*fmt == '[') + return num; fmt++; + } while (!isspace(*str) && *str) str++; continue; @@ -2212,7 +3511,7 @@ int vsscanf(const char *buf, const char *fmt, va_list args) /* get conversion qualifier */ qualifier = -1; if (*fmt == 'h' || _tolower(*fmt) == 'l' || - _tolower(*fmt) == 'z') { + *fmt == 'z') { qualifier = *fmt++; if (unlikely(qualifier == *fmt)) { if (qualifier == 'h') { @@ -2239,7 +3538,7 @@ int vsscanf(const char *buf, const char *fmt, va_list args) break; base = 10; - is_sign = 0; + is_sign = false; switch (*fmt++) { case 'c': @@ -2268,6 +3567,59 @@ int vsscanf(const char *buf, const char *fmt, va_list args) num++; } continue; + /* + * Warning: This implementation of the '[' conversion specifier + * deviates from its glibc counterpart in the following ways: + * (1) It does NOT support ranges i.e. '-' is NOT a special + * character + * (2) It cannot match the closing bracket ']' itself + * (3) A field width is required + * (4) '%*[' (discard matching input) is currently not supported + * + * Example usage: + * ret = sscanf("00:0a:95","%2[^:]:%2[^:]:%2[^:]", + * buf1, buf2, buf3); + * if (ret < 3) + * // etc.. + */ + case '[': + { + char *s = (char *)va_arg(args, char *); + DECLARE_BITMAP(set, 256) = {0}; + unsigned int len = 0; + bool negate = (*fmt == '^'); + + /* field width is required */ + if (field_width == -1) + return num; + + if (negate) + ++fmt; + + for ( ; *fmt && *fmt != ']'; ++fmt, ++len) + __set_bit((u8)*fmt, set); + + /* no ']' or no character set found */ + if (!*fmt || !len) + return num; + ++fmt; + + if (negate) { + bitmap_complement(set, set, 256); + /* exclude null '\0' byte */ + __clear_bit(0, set); + } + + /* match must be non-empty */ + if (!test_bit((u8)*str, set)) + return num; + + while (test_bit((u8)*str, set) && field_width--) + *s++ = *str++; + *s = '\0'; + ++num; + } + continue; case 'o': base = 8; break; @@ -2277,8 +3629,10 @@ int vsscanf(const char *buf, const char *fmt, va_list args) break; case 'i': base = 0; + fallthrough; case 'd': - is_sign = 1; + is_sign = true; + fallthrough; case 'u': break; case '%': @@ -2297,36 +3651,26 @@ int vsscanf(const char *buf, const char *fmt, va_list args) str = skip_spaces(str); digit = *str; - if (is_sign && digit == '-') + if (is_sign && digit == '-') { + if (field_width == 1) + break; + digit = *(str + 1); + } if (!digit || (base == 16 && !isxdigit(digit)) || (base == 10 && !isdigit(digit)) - || (base == 8 && (!isdigit(digit) || digit > '7')) + || (base == 8 && !isodigit(digit)) || (base == 0 && !isdigit(digit))) break; if (is_sign) - val.s = qualifier != 'L' ? - simple_strtol(str, &next, base) : - simple_strtoll(str, &next, base); + val.s = simple_strntoll(str, &next, base, + field_width >= 0 ? field_width : INT_MAX); else - val.u = qualifier != 'L' ? - simple_strtoul(str, &next, base) : - simple_strtoull(str, &next, base); - - if (field_width > 0 && next - str > field_width) { - if (base == 0) - _parse_integer_fixup_radix(str, &base); - while (next - str > field_width) { - if (is_sign) - val.s = div_s64(val.s, base); - else - val.u = div_u64(val.u, base); - --next; - } - } + val.u = simple_strntoull(str, &next, base, + field_width >= 0 ? field_width : INT_MAX); switch (qualifier) { case 'H': /* that's 'hh' in format */ @@ -2353,7 +3697,6 @@ int vsscanf(const char *buf, const char *fmt, va_list args) else *va_arg(args, unsigned long long *) = val.u; break; - case 'Z': case 'z': *va_arg(args, size_t *) = val.u; break; |