[PATCH 3.16.y-ckt 065/129] iio: inkern: fix a NULL dereference on error

[Luis Henriques]

3.16.7-ckt25 -stable review patch.  If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Dan Carpenter <dan.carpenter at oracle.com>

commit d81dac3c1c5295c61b15293074ac2bd3254e1875 upstream.

In twl4030_bci_probe() there are some failure paths where we call
iio_channel_release() with a NULL pointer.  (Apparently, that driver can
opperate without a valid channel pointer).  Let's fix it by adding a
NULL check in iio_channel_release().

Fixes: 2202e1fc5a29 ('drivers: power: twl4030_charger: fix link problems when building as module')
Signed-off-by: Dan Carpenter <dan.carpenter at oracle.com>
Signed-off-by: Jonathan Cameron <jic23 at kernel.org>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/iio/inkern.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index f0846108d006..3978c0d89ae1 100644
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -325,6 +325,8 @@ EXPORT_SYMBOL_GPL(iio_channel_get);
 
 void iio_channel_release(struct iio_channel *channel)
 {
+	if (!channel)
+		return;
 	iio_device_put(channel->indio_dev);
 	kfree(channel);
 }