Re: [PATCH] iio: cros_ec_accel_legacy: Mark expected switch fall-throughs

[Kees Cook]

On Mon, Oct 8, 2018 at 10:24 AM Gustavo A. R. Silva
<gustavo@xxxxxxxxxxxxxx> wrote:
>
> In preparation to enabling -Wimplicit-fallthrough, mark switch cases
> where we are expecting to fall through.
>
> Addresses-Coverity-ID: 1397962 ("Missing break in switch")
> Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
> ---
>  drivers/iio/accel/cros_ec_accel_legacy.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/iio/accel/cros_ec_accel_legacy.c b/drivers/iio/accel/cros_ec_accel_legacy.c
> index 063e89e..d609654 100644
> --- a/drivers/iio/accel/cros_ec_accel_legacy.c
> +++ b/drivers/iio/accel/cros_ec_accel_legacy.c
> @@ -385,8 +385,10 @@ static int cros_ec_accel_legacy_probe(struct platform_device *pdev)
>                 switch (i) {
>                 case X:
>                         ec_accel_channels[X].scan_index = Y;
> +                       /* fall through */
>                 case Y:
>                         ec_accel_channels[Y].scan_index = X;
> +                       /* fall through */
>                 case Z:
>                         ec_accel_channels[Z].scan_index = Z;
>                 }

Shouldn't these actually be "break;"s ? It seems like the loop is
stepping through X, Y, and Z. The _result_ is accidentally the same:

X: set X, Y, and Z
Y: set Y and Z
Z: set Z

result: X, Y, and Z are set correctly. But the code is technically wrong.


-- 
Kees Cook