Re: [PATCH] iio: chemical: scd30: fix division by zero in write_raw

Jonathan Cameron
2026-04-20T14:31:56Z

On Wed, 1 Apr 2026 14:08:29 +0300
Antoniu Miclaus <antoniu.miclaus@analog.com> wrote:

> Add a zero check for val2 before using it as a divisor when setting the
> sampling frequency. A user writing a zero fractional part to the
> sampling_frequency sysfs attribute triggers a division by zero in the
> kernel.
>
> Fixes: 64b3d8b1b0f5 ("iio: chemical: scd30: add core driver")
> Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
Applied to fixes-togreg and marked for stable.

Thanks,

J
> ---
> drivers/iio/chemical/scd30_core.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iio/chemical/scd30_core.c b/drivers/iio/chemical/scd30_core.c
> index a665fcb78806..11d6bc1b63e6 100644
> --- a/drivers/iio/chemical/scd30_core.c
> +++ b/drivers/iio/chemical/scd30_core.c
> @@ -256,7 +256,7 @@ static int scd30_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const
> guard(mutex)(&state->lock);
> switch (mask) {
> case IIO_CHAN_INFO_SAMP_FREQ:
> - if (val)
> + if (val || !val2)
> return -EINVAL;
>
> val = 1000000000 / val2;