iio: adc: rockchip_saradc: fix information leak in triggered buffer

iio: adc: rockchip_saradc: fix information leak in triggered buffer

commit 38724591364e1e3b278b4053f102b49ea06ee17c upstream.

The 'data' local struct is used to push data to user space from a
triggered buffer, but it does not set values for inactive channels, as
it only uses iio_for_each_active_channel() to assign new values.

Initialize the struct to zero before using it to avoid pushing
uninitialized information to userspace.

Cc: stable@vger.kernel.org
Fixes: 4e130dc7b413 ("iio: adc: rockchip_saradc: Add support iio buffers")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Link: https://patch.msgid.link/20241125-iio_memset_scan_holes-v1-4-0cb6e98d895c@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Bin Lan <lanbincn@qq.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>