diff options
author | Jan Beulich <JBeulich@suse.com> | 2012-12-17 16:01:31 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-12-17 17:15:18 -0800 |
commit | 53809751ac230a3611b5cdd375f3389f3207d471 (patch) | |
tree | 8555da83945aaba9291f0d9ff09d271043e36263 | |
parent | 375da3a76dc49f10c35e243ebef62df12e3adf4e (diff) |
sscanf: don't ignore field widths for numeric conversions
This is another step towards better standard conformance. Rather than
adding a local buffer to store the specified portion of the string (with
the need to enforce an arbitrary maximum supported width to limit the
buffer size), do a maximum width conversion and then drop as much of it as
is necessary to meet the caller's request.
Also fail on negative field widths.
Uses the deprecated simple_strto*() functions because kstrtoXX() fail on
non-zero terminated strings.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r-- | lib/vsprintf.c | 96 |
1 files changed, 53 insertions, 43 deletions
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 41da0741a66..292fcb174a3 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -23,12 +23,12 @@ #include <linux/ctype.h> #include <linux/kernel.h> #include <linux/kallsyms.h> +#include <linux/math64.h> #include <linux/uaccess.h> #include <linux/ioport.h> #include <net/addrconf.h> #include <asm/page.h> /* for PAGE_SIZE */ -#include <asm/div64.h> #include <asm/sections.h> /* for dereference_function_descriptor() */ #include "kstrtox.h" @@ -2016,7 +2016,11 @@ int vsscanf(const char *buf, const char *fmt, va_list args) char digit; int num = 0; u8 qualifier; - u8 base; + unsigned int base; + union { + long long s; + unsigned long long u; + } val; s16 field_width; bool is_sign; @@ -2056,8 +2060,11 @@ int vsscanf(const char *buf, const char *fmt, va_list args) /* get field width */ field_width = -1; - if (isdigit(*fmt)) + if (isdigit(*fmt)) { field_width = skip_atoi(&fmt); + if (field_width <= 0) + break; + } /* get conversion qualifier */ qualifier = -1; @@ -2157,58 +2164,61 @@ int vsscanf(const char *buf, const char *fmt, va_list args) || (base == 0 && !isdigit(digit))) break; + if (is_sign) + val.s = qualifier != 'L' ? + simple_strtol(str, &next, base) : + simple_strtoll(str, &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; + } + } + switch (qualifier) { case 'H': /* that's 'hh' in format */ - if (is_sign) { - signed char *s = (signed char *)va_arg(args, signed char *); - *s = (signed char)simple_strtol(str, &next, base); - } else { - unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); - *s = (unsigned char)simple_strtoul(str, &next, base); - } + if (is_sign) + *va_arg(args, signed char *) = val.s; + else + *va_arg(args, unsigned char *) = val.u; break; case 'h': - if (is_sign) { - short *s = (short *)va_arg(args, short *); - *s = (short)simple_strtol(str, &next, base); - } else { - unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); - *s = (unsigned short)simple_strtoul(str, &next, base); - } + if (is_sign) + *va_arg(args, short *) = val.s; + else + *va_arg(args, unsigned short *) = val.u; break; case 'l': - if (is_sign) { - long *l = (long *)va_arg(args, long *); - *l = simple_strtol(str, &next, base); - } else { - unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); - *l = simple_strtoul(str, &next, base); - } + if (is_sign) + *va_arg(args, long *) = val.s; + else + *va_arg(args, unsigned long *) = val.u; break; case 'L': - if (is_sign) { - long long *l = (long long *)va_arg(args, long long *); - *l = simple_strtoll(str, &next, base); - } else { - unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); - *l = simple_strtoull(str, &next, base); - } + if (is_sign) + *va_arg(args, long long *) = val.s; + else + *va_arg(args, unsigned long long *) = val.u; break; case 'Z': case 'z': - { - size_t *s = (size_t *)va_arg(args, size_t *); - *s = (size_t)simple_strtoul(str, &next, base); - } - break; + *va_arg(args, size_t *) = val.u; + break; default: - if (is_sign) { - int *i = (int *)va_arg(args, int *); - *i = (int)simple_strtol(str, &next, base); - } else { - unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); - *i = (unsigned int)simple_strtoul(str, &next, base); - } + if (is_sign) + *va_arg(args, int *) = val.s; + else + *va_arg(args, unsigned int *) = val.u; break; } num++; |