This is a note to let you know that I've just added the patch titled
iio:accel:mxc4005: rearrange iio trigger get and register
to my char-misc git tree which can be found at
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
in the char-misc-linus branch.
The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)
The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.
If you have any questions about this process, please let me know.
>From 9354c224c9b4f55847a0de3e968cba2ebf15af3b Mon Sep 17 00:00:00 2001
From: Dmitry Rokosov <DDRokosov@xxxxxxxxxxxxxx>
Date: Tue, 24 May 2022 18:14:43 +0000
Subject: iio:accel:mxc4005: rearrange iio trigger get and register
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: 47196620c82f ("iio: mxc4005: add data ready trigger for mxc4005")
Signed-off-by: Dmitry Rokosov <ddrokosov@xxxxxxxxxxxxxx>
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Link: https://lore.kernel.org/r/20220524181150.9240-4-ddrokosov@xxxxxxxxxxxxxx
Cc: <Stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
---
drivers/iio/accel/mxc4005.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/iio/accel/mxc4005.c b/drivers/iio/accel/mxc4005.c
index b3afbf064915..df600d2917c0 100644
--- a/drivers/iio/accel/mxc4005.c
+++ b/drivers/iio/accel/mxc4005.c
@@ -456,8 +456,6 @@ static int mxc4005_probe(struct i2c_client *client,
data->dready_trig->ops = &mxc4005_trigger_ops;
iio_trigger_set_drvdata(data->dready_trig, indio_dev);
- indio_dev->trig = data->dready_trig;
- iio_trigger_get(indio_dev->trig);
ret = devm_iio_trigger_register(&client->dev,
data->dready_trig);
if (ret) {
@@ -465,6 +463,8 @@ static int mxc4005_probe(struct i2c_client *client,
"failed to register trigger\n");
return ret;
}
+
+ indio_dev->trig = iio_trigger_get(data->dready_trig);
}
return devm_iio_device_register(&client->dev, indio_dev);
--
2.36.1
