The macro previously introduced in the compat code to replace kstrtou32() may not work properly in case of a too large user input. Fix it by using a temporary variable of the proper length and then cast the result. Possibly return -ERANGE is the result is too big to fix a 32bit long variable. Cc: Matthias Schiffer &lt;mschiffer(a)universe-factory.net&gt; Signed-off-by: Antonio Quartulli &lt;antonio(a)meshcoding.com&gt; --- compat.h | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/compat.h b/compat.h index a050bb8..6daeff9 100644 --- a/compat.h +++ b/compat.h @@ -152,8 +152,16 @@ static inline int batadv_param_set_copystring(const char *val, #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 39) -/* cast last argument of strict_strtoul() because we have a uint32_t */ -#define kstrtou32(cp, base, v) strict_strtoul(cp, base, (unsigned long *)v) +#define kstrtou32(cp, base, v)\ +({\ + unsigned long _v;\ + int _r;\ + _r = strict_strtoul(cp, base, &_v);\ + *(v) = (uint32_t)_v;\ + if ((unsigned long)*(v) != _v)\ + _r = -ERANGE;\ + _r;\ +}) #define kstrtoul strict_strtoul #define kstrtol strict_strtol -- 1.8.4.4