diff options
| -rw-r--r-- | lib/kstrtox.c | 13 | ||||
| -rw-r--r-- | lib/kstrtox.h | 2 | ||||
| -rw-r--r-- | lib/vsprintf.c | 82 |
3 files changed, 60 insertions, 37 deletions
diff --git a/lib/kstrtox.c b/lib/kstrtox.c index a118b0b1e9b2..0b5fe8b41173 100644 --- a/lib/kstrtox.c +++ b/lib/kstrtox.c @@ -39,20 +39,22 @@ const char *_parse_integer_fixup_radix(const char *s, unsigned int *base) /* * Convert non-negative integer string representation in explicitly given radix - * to an integer. + * to an integer. A maximum of max_chars characters will be converted. + * * Return number of characters consumed maybe or-ed with overflow bit. * If overflow occurs, result integer (incorrect) is still returned. * * Don't you dare use this function. */ -unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *p) +unsigned int _parse_integer_limit(const char *s, unsigned int base, unsigned long long *p, + size_t max_chars) { unsigned long long res; unsigned int rv; res = 0; rv = 0; - while (1) { + while (max_chars--) { unsigned int c = *s; unsigned int lc = c | 0x20; /* don't tolower() this line */ unsigned int val; @@ -82,6 +84,11 @@ unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long return rv; } +unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *p) +{ + return _parse_integer_limit(s, base, p, INT_MAX); +} + static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res) { unsigned long long _res; diff --git a/lib/kstrtox.h b/lib/kstrtox.h index 3b4637bcd254..158c400ca865 100644 --- a/lib/kstrtox.h +++ b/lib/kstrtox.h @@ -4,6 +4,8 @@ #define KSTRTOX_OVERFLOW (1U << 31) const char *_parse_integer_fixup_radix(const char *s, unsigned int *base); +unsigned int _parse_integer_limit(const char *s, unsigned int base, unsigned long long *res, + size_t max_chars); unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *res); #endif diff --git a/lib/vsprintf.c b/lib/vsprintf.c index af307588ad8b..3290eca46e47 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -53,6 +53,31 @@ #include <linux/string_helpers.h> #include "kstrtox.h" +static unsigned long long simple_strntoull(const char *startp, size_t max_chars, + char **endp, unsigned int base) +{ + const char *cp; + unsigned long long result = 0ULL; + size_t prefix_chars; + unsigned int rv; + + 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 @@ -63,18 +88,7 @@ */ unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) { - unsigned long long result; - unsigned int rv; - - cp = _parse_integer_fixup_radix(cp, &base); - rv = _parse_integer(cp, base, &result); - /* FIXME */ - cp += (rv & ~KSTRTOX_OVERFLOW); - - if (endp) - *endp = (char *)cp; - - return result; + return simple_strntoull(cp, INT_MAX, endp, base); } EXPORT_SYMBOL(simple_strtoull); @@ -109,6 +123,21 @@ long simple_strtol(const char *cp, char **endp, unsigned int base) } EXPORT_SYMBOL(simple_strtol); +static long long simple_strntoll(const char *cp, size_t max_chars, char **endp, + unsigned int base) +{ + /* + * 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, max_chars - 1, endp, base); + + return simple_strntoull(cp, max_chars, endp, base); +} + /** * simple_strtoll - convert a string to a signed long long * @cp: The start of the string @@ -119,10 +148,7 @@ EXPORT_SYMBOL(simple_strtol); */ 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, INT_MAX, endp, base); } EXPORT_SYMBOL(simple_strtoll); @@ -3541,25 +3567,13 @@ int vsscanf(const char *buf, const char *fmt, va_list args) break; if (is_sign) - val.s = qualifier != 'L' ? - simple_strtol(str, &next, base) : - simple_strtoll(str, &next, base); + val.s = simple_strntoll(str, + field_width >= 0 ? field_width : INT_MAX, + &next, base); 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, + field_width >= 0 ? field_width : INT_MAX, + &next, base); switch (qualifier) { case 'H': /* that's 'hh' in format */ |