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

[Andy Shevchenko]

On Thu, Feb 4, 2016 at 11:00 PM, Kees Cook <keescook@xxxxxxxxxxxx> 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@xxxxxxxxxxxx>

Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>

One minor below.

> ---
>  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?

>
>  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