On Mon, Apr 06, 2020 at 02:03:12PM +0200, Christoph Hellwig wrote: > + int len = strnlen(arg, MAX_ARG_STRLEN) + 1 /* terminating null */; If you end up doing another version of this, it's a terminating NUL, not null. I almost wonder if we shouldn't have #define TERMINATING_NUL 1 in kernel.h. int len = strnlen(arg, MAX_ARG_STRLEN) + TERMINATING_NUL; has a certain appeal. There's the risk people might misuse it though ... str[end] = TERMINATING_NUL; so probably not a good idea.