[PATCH v2 1/4] lib: move strtobool to kstrtobool

Kees Cook keescook at chromium.org
Fri Feb 5 09:48:57 AEDT 2016


On Thu, Feb 4, 2016 at 2:43 PM, Andy Shevchenko
<andy.shevchenko at gmail.com> wrote:
> On Thu, Feb 4, 2016 at 11:00 PM, Kees Cook <keescook at chromium.org> wrote:
>> Create the kstrtobool_from_user helper and moves strtobool logic into
>> the new kstrtobool (matching all the other kstrto* functions). Provides
>> an inline wrapper for existing strtobool callers.
>>
>> Signed-off-by: Kees Cook <keescook at chromium.org>
>
> Reviewed-by: Andy Shevchenko <andy.shevchenko at gmail.com>
>
> One minor below.

Thanks!

>
>> ---
>>  include/linux/kernel.h |  3 +++
>>  include/linux/string.h |  6 +++++-
>>  lib/kstrtox.c          | 35 +++++++++++++++++++++++++++++++++++
>>  lib/string.c           | 29 -----------------------------
>>  4 files changed, 43 insertions(+), 30 deletions(-)
>>
>> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
>> index f31638c6e873..cdc25f47a23f 100644
>> --- a/include/linux/kernel.h
>> +++ b/include/linux/kernel.h
>> @@ -357,6 +357,7 @@ int __must_check kstrtou16(const char *s, unsigned int base, u16 *res);
>>  int __must_check kstrtos16(const char *s, unsigned int base, s16 *res);
>>  int __must_check kstrtou8(const char *s, unsigned int base, u8 *res);
>>  int __must_check kstrtos8(const char *s, unsigned int base, s8 *res);
>> +int __must_check kstrtobool(const char *s, unsigned int base, bool *res);
>>
>>  int __must_check kstrtoull_from_user(const char __user *s, size_t count, unsigned int base, unsigned long long *res);
>>  int __must_check kstrtoll_from_user(const char __user *s, size_t count, unsigned int base, long long *res);
>> @@ -368,6 +369,8 @@ int __must_check kstrtou16_from_user(const char __user *s, size_t count, unsigne
>>  int __must_check kstrtos16_from_user(const char __user *s, size_t count, unsigned int base, s16 *res);
>>  int __must_check kstrtou8_from_user(const char __user *s, size_t count, unsigned int base, u8 *res);
>>  int __must_check kstrtos8_from_user(const char __user *s, size_t count, unsigned int base, s8 *res);
>
>> +int __must_check kstrtobool_from_user(const char __user *s, size_t count,
>> +                                     unsigned int base, bool *res);
>
> We already are using long lines here, perhaps do the same?

I went back and forth on that, and decided that between checkpatch
yelling at me, and trying to be an agent of less entropy, I wrapped
the definition. I am fine either way, though.

-Kees

>
>>
>>  static inline int __must_check kstrtou64_from_user(const char __user *s, size_t count, unsigned int base, u64 *res)
>>  {
>> diff --git a/include/linux/string.h b/include/linux/string.h
>> index 9eebc66d957a..d2fb21b1081d 100644
>> --- a/include/linux/string.h
>> +++ b/include/linux/string.h
>> @@ -128,7 +128,11 @@ extern char **argv_split(gfp_t gfp, const char *str, int *argcp);
>>  extern void argv_free(char **argv);
>>
>>  extern bool sysfs_streq(const char *s1, const char *s2);
>> -extern int strtobool(const char *s, bool *res);
>> +extern int kstrtobool(const char *s, unsigned int base, bool *res);
>> +static inline int strtobool(const char *s, bool *res)
>> +{
>> +       return kstrtobool(s, 0, res);
>> +}
>>
>>  #ifdef CONFIG_BINARY_PRINTF
>>  int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args);
>> diff --git a/lib/kstrtox.c b/lib/kstrtox.c
>> index 94be244e8441..e18f088704d7 100644
>> --- a/lib/kstrtox.c
>> +++ b/lib/kstrtox.c
>> @@ -321,6 +321,40 @@ int kstrtos8(const char *s, unsigned int base, s8 *res)
>>  }
>>  EXPORT_SYMBOL(kstrtos8);
>>
>> +/**
>> + * kstrtobool - convert common user inputs into boolean values
>> + * @s: input string
>> + * @base: ignored
>> + * @res: result
>> + *
>> + * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
>> + * Otherwise it will return -EINVAL.  Value pointed to by res is
>> + * updated upon finding a match.
>> + */
>> +int kstrtobool(const char *s, unsigned int base, bool *res)
>> +{
>> +       if (!s)
>> +               return -EINVAL;
>> +
>> +       switch (s[0]) {
>> +       case 'y':
>> +       case 'Y':
>> +       case '1':
>> +               *res = true;
>> +               return 0;
>> +       case 'n':
>> +       case 'N':
>> +       case '0':
>> +               *res = false;
>> +               return 0;
>> +       default:
>> +               break;
>> +       }
>> +
>> +       return -EINVAL;
>> +}
>> +EXPORT_SYMBOL(kstrtobool);
>> +
>>  #define kstrto_from_user(f, g, type)                                   \
>>  int f(const char __user *s, size_t count, unsigned int base, type *res)        \
>>  {                                                                      \
>> @@ -345,3 +379,4 @@ kstrto_from_user(kstrtou16_from_user,       kstrtou16,      u16);
>>  kstrto_from_user(kstrtos16_from_user,  kstrtos16,      s16);
>>  kstrto_from_user(kstrtou8_from_user,   kstrtou8,       u8);
>>  kstrto_from_user(kstrtos8_from_user,   kstrtos8,       s8);
>> +kstrto_from_user(kstrtobool_from_user, kstrtobool,     bool);
>> diff --git a/lib/string.c b/lib/string.c
>> index 0323c0d5629a..1a90db9bc6e1 100644
>> --- a/lib/string.c
>> +++ b/lib/string.c
>> @@ -630,35 +630,6 @@ bool sysfs_streq(const char *s1, const char *s2)
>>  }
>>  EXPORT_SYMBOL(sysfs_streq);
>>
>> -/**
>> - * strtobool - convert common user inputs into boolean values
>> - * @s: input string
>> - * @res: result
>> - *
>> - * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
>> - * Otherwise it will return -EINVAL.  Value pointed to by res is
>> - * updated upon finding a match.
>> - */
>> -int strtobool(const char *s, bool *res)
>> -{
>> -       switch (s[0]) {
>> -       case 'y':
>> -       case 'Y':
>> -       case '1':
>> -               *res = true;
>> -               break;
>> -       case 'n':
>> -       case 'N':
>> -       case '0':
>> -               *res = false;
>> -               break;
>> -       default:
>> -               return -EINVAL;
>> -       }
>> -       return 0;
>> -}
>> -EXPORT_SYMBOL(strtobool);
>> -
>>  #ifndef __HAVE_ARCH_MEMSET
>>  /**
>>   * memset - Fill a region of memory with the given value
>> --
>> 2.6.3
>>
>
>
>
> --
> With Best Regards,
> Andy Shevchenko



-- 
Kees Cook
Chrome OS & Brillo Security


More information about the Linuxppc-dev mailing list