On Thu, Jul 27, 2023 at 09:46:36PM -0700, Elliott Mitchell wrote: > On Thu, Jul 27, 2023 at 09:53:24PM +0000, Justin Stitt wrote: > > Technically, my patch yields subtly different behavior. The original > > implementation with `strncpy` would fill the entire destination buffer > > with null bytes [3] while `strscpy` will leave the junk, uninitialized > > bytes trailing after the _mandatory_ NUL-termination. So, if somehow > > `pcm->name` or `card->driver/shortname/longname` require this > > NUL-padding behavior then `strscpy_pad` should be used. My > > interpretation, though, is that the aforementioned fields are just fine > > as NUL-terminated strings. Please correct my assumptions if needed and > > I'll send in a v2. > > "uninitialized bytes" => "leak of sensitive information" => "security hole" For xen_snd_front_alsa_init(), "card" is already zero-initialized in snd_card_new(). For new_pcm_instance(), "pcm" is already zero-initialized in _snd_pcm_new(). So things look good to me! Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx> -- Kees Cook
