Re: [PATCH] staging: greybus: audio_helper.c: Replace strlcpy() with strscpy()

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Sat, Jan 09, 2021 at 06:57:31PM +0530, B K Karthik wrote:
> In gbaudio_remove_controls() , replace the usage of strlcpy() with
> strscpy() because strlcpy() only limits the *destination*
> size, and the source is always read fully.
> 
> https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
> was quoted by checkpatch while showing this warning.
> 
> Signed-off-by: B K Karthik <bkkarthik@pesu.pes.edu>
> ---
>  drivers/staging/greybus/audio_helper.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/staging/greybus/audio_helper.c b/drivers/staging/greybus/audio_helper.c
> index 3011b8abce38..1ed4772d2771 100644
> --- a/drivers/staging/greybus/audio_helper.c
> +++ b/drivers/staging/greybus/audio_helper.c
> @@ -166,7 +166,7 @@ static int gbaudio_remove_controls(struct snd_card *card, struct device *dev,
>  			snprintf(id.name, sizeof(id.name), "%s %s", prefix,
>  				 control->name);
>  		else
> -			strlcpy(id.name, control->name, sizeof(id.name));
> +			strscpy(id.name, control->name, sizeof(id.name));

Is this something that matters here?  Isn't the string coming from the
kernel (i.e. a trusted source), or if not, where is it coming from?

thanks,

greg k-h