diff options
author | Ma Ke <make24@iscas.ac.cn> | 2025-03-19 11:02:48 +0300 |
---|---|---|
committer | Hans Verkuil <hverkuil@xs4all.nl> | 2025-05-09 12:55:06 +0300 |
commit | 2a934fdb01db6458288fc9386d3d8ceba6dd551a (patch) | |
tree | de05516e23af67f39b63057574faa4072d01ccb6 | |
parent | 48dbb76cef65fabaa3ac97461eda90495e954ecd (diff) | |
download | linux-2a934fdb01db6458288fc9386d3d8ceba6dd551a.tar.xz |
media: v4l2-dev: fix error handling in __video_register_device()
Once device_register() failed, we should call put_device() to
decrement reference count for cleanup. Or it could cause memory leak.
And move callback function v4l2_device_release() and v4l2_device_get()
before put_device().
As comment of device_register() says, 'NOTE: _Never_ directly free
@dev after calling this function, even if it returned an error! Always
use put_device() to give up the reference initialized in this function
instead.'
Found by code review.
Cc: stable@vger.kernel.org
Fixes: dc93a70cc7f9 ("V4L/DVB (9973): v4l2-dev: use the release callback from device instead of cdev")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
-rw-r--r-- | drivers/media/v4l2-core/v4l2-dev.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/drivers/media/v4l2-core/v4l2-dev.c b/drivers/media/v4l2-core/v4l2-dev.c index b40c08ce909d..c369235113d9 100644 --- a/drivers/media/v4l2-core/v4l2-dev.c +++ b/drivers/media/v4l2-core/v4l2-dev.c @@ -1054,25 +1054,25 @@ int __video_register_device(struct video_device *vdev, vdev->dev.class = &video_class; vdev->dev.devt = MKDEV(VIDEO_MAJOR, vdev->minor); vdev->dev.parent = vdev->dev_parent; + vdev->dev.release = v4l2_device_release; dev_set_name(&vdev->dev, "%s%d", name_base, vdev->num); + + /* Increase v4l2_device refcount */ + v4l2_device_get(vdev->v4l2_dev); + mutex_lock(&videodev_lock); ret = device_register(&vdev->dev); if (ret < 0) { mutex_unlock(&videodev_lock); pr_err("%s: device_register failed\n", __func__); - goto cleanup; + put_device(&vdev->dev); + return ret; } - /* Register the release callback that will be called when the last - reference to the device goes away. */ - vdev->dev.release = v4l2_device_release; if (nr != -1 && nr != vdev->num && warn_if_nr_in_use) pr_warn("%s: requested %s%d, got %s\n", __func__, name_base, nr, video_device_node_name(vdev)); - /* Increase v4l2_device refcount */ - v4l2_device_get(vdev->v4l2_dev); - /* Part 5: Register the entity. */ ret = video_register_media_controller(vdev); |