iio: pressure: zpa2326: fix information leak in triggered buffer

BugLink: https://bugs.launchpad.net/bugs/2097298

commit 6007d10 upstream.

The 'sample' local struct is used to push data to user space from a
triggered buffer, but it has a hole between the temperature and the
timestamp (u32 pressure, u16 temperature, GAP, u64 timestamp).
This hole is never initialized.

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

Cc: stable@vger.kernel.org
Fixes: 03b262f ("iio:pressure: initial zpa2326 barometer support")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Link: https://patch.msgid.link/20241125-iio_memset_scan_holes-v1-3-0cb6e98d895c@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Noah Wager <noah.wager@canonical.com>
Signed-off-by: Koichiro Den <koichiro.den@canonical.com>

Author: javiercarrascocruz

drivers/iio/pressure/zpa2326.c

@@ -586,6 +586,8 @@ static int zpa2326_fill_sample_buffer(struct iio_dev               *indio_dev,
 	}   sample;
 	int err;
 
+	memset(&sample, 0, sizeof(sample));
+
 	if (test_bit(0, indio_dev->active_scan_mask)) {
 		/* Get current pressure from hardware FIFO. */
 		err = zpa2326_dequeue_pressure(indio_dev, &sample.pressure);