From: Darshana Padmadas <darshanapadmadas@gmail.com>
Date: Sat, 28 Mar 2015 06:37:14 +0000 (+0530)
Subject: iio: imu: Use iio_trigger_get for indio_dev->trig assignment
X-Git-Tag: v4.9.8~4546^2^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=4ce7ca89d6e8eae9e201cd0e972ba323f33e2fb4;p=platform%2Fkernel%2Flinux-rpi3.git

iio: imu: Use iio_trigger_get for indio_dev->trig assignment

This patch uses iio_trigger_get to increment the reference
count of trigger device, to avoid incorrect assignment.
Can result in a null pointer dereference during removal if the
trigger has been changed before removal.

This patch refers to a similar situation encountered through the
following discussion:
http://www.spinics.net/lists/linux-iio/msg13669.html

Signed-off-by: Darshana Padmadas <darshanapadmadas@gmail.com>
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
---

diff --git a/drivers/iio/imu/adis_trigger.c b/drivers/iio/imu/adis_trigger.c
index e0017c2..f53e9a8 100644
--- a/drivers/iio/imu/adis_trigger.c
+++ b/drivers/iio/imu/adis_trigger.c
@@ -60,7 +60,7 @@ int adis_probe_trigger(struct adis *adis, struct iio_dev *indio_dev)
 	iio_trigger_set_drvdata(adis->trig, adis);
 	ret = iio_trigger_register(adis->trig);
 
-	indio_dev->trig = adis->trig;
+	indio_dev->trig = iio_trigger_get(adis->trig);
 	if (ret)
 		goto error_free_irq;