iio:chemical:ccs811: rearrange iio trigger get and register
authorDmitry Rokosov <DDRokosov@sberdevices.ru>
Tue, 24 May 2022 18:14:45 +0000 (18:14 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 29 Jun 2022 07:03:28 +0000 (09:03 +0200)
commita1356318042ed84ada9de7bcc3887562e78e729c
tree6609590a0b95d7742129f00b8a86231128e1f8b7
parent974e69beebb3ca6bf51b1a7734fbc8d67c228f10
iio:chemical:ccs811: rearrange iio trigger get and register

commit d710359c0b445e8c03e24f19ae2fb79ce7282260 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: f1f065d7ac30 ("iio: chemical: ccs811: Add support for data ready trigger")
Signed-off-by: Dmitry Rokosov <ddrokosov@sberdevices.ru>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20220524181150.9240-5-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/chemical/ccs811.c