From: Dmitry Rokosov DDRokosov@sberdevices.ru
commit e5f3205b04d7f95a2ef43bce4b454a7f264d6923 upstream.
IIO trigger interface function iio_trigger_get() should be called after iio_trigger_register() (or its devm analogue) strictly, because of iio_trigger_get() acquires module refcnt based on the trigger->owner pointer, which is initialized inside iio_trigger_register() to THIS_MODULE. If this call order is wrong, the next iio_trigger_put() (from sysfs callback or "delete module" path) will dereference "default" module refcnt, which is incorrect behaviour.
Fixes: 0668a4e4d297 ("iio: accel: bma180: Fix indio_dev->trig assignment") Signed-off-by: Dmitry Rokosov ddrokosov@sberdevices.ru Reviewed-by: Andy Shevchenko andy.shevchenko@gmail.com Link: https://lore.kernel.org/r/20220524181150.9240-2-ddrokosov@sberdevices.ru Cc: Stable@vger.kernel.org Signed-off-by: Jonathan Cameron Jonathan.Cameron@huawei.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/iio/accel/bma180.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/iio/accel/bma180.c +++ b/drivers/iio/accel/bma180.c @@ -793,11 +793,12 @@ static int bma180_probe(struct i2c_clien data->trig->dev.parent = &client->dev; data->trig->ops = &bma180_trigger_ops; iio_trigger_set_drvdata(data->trig, indio_dev); - indio_dev->trig = iio_trigger_get(data->trig);
ret = iio_trigger_register(data->trig); if (ret) goto err_trigger_free; + + indio_dev->trig = iio_trigger_get(data->trig); }
ret = iio_triggered_buffer_setup(indio_dev, NULL,