iio: inkern: call iio_device_put() only on mapped devices

commit 64f43895b4457532a3cc524ab250b7a30739a1b1 upstream.

In the error path of iio_channel_get_all(), iio_device_put() is called
on all IIO devices, which can cause a refcount imbalance. Fix this error
by calling iio_device_put() only on IIO devices whose refcounts were
previously incremented by iio_device_get().

Fixes: 314be14bb893 ("iio: Rename _st_ functions to loose the bit that meant the staging version.")
Signed-off-by: Joe Hattori <joe@pf.is.s.u-tokyo.ac.jp>
Link: https://patch.msgid.link/20241204111342.1246706-1-joe@pf.is.s.u-tokyo.ac.jp
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c
index 6e64ffde6c82d6a851d2f86a6a968b9934b30a8e..03581a3487751d28dd92d4fee43a369cc69d7c1d 100644 (file)
--- a/drivers/iio/inkern.c
+++ b/drivers/iio/inkern.c
@@ -447,7 +447,7 @@ struct iio_channel *iio_channel_get_all(struct device *dev)
        return chans;
 
 error_free_chans:
-       for (i = 0; i < nummaps; i++)
+       for (i = 0; i < mapind; i++)
                iio_device_put(chans[i].indio_dev);
        kfree(chans);
 error_ret: