V4L/DVB (8414): videodev/cx18: fix get_index bug and error-handling lock-ups

Fix a bug in get_index that was introduced earlier.
Also fix two error handling lock-ups in videodev and cx18 that
where found thanks to that bug.
Signed-off-by: NHans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: NMauro Carvalho Chehab <mchehab@infradead.org>

drivers/media/video/cx18/cx18-streams.c

@@ -311,8 +311,10 @@ void cx18_streams_cleanup(struct cx18 *cx, int unregister)
 
 	/* Teardown all streams */
 	for (type = 0; type < CX18_MAX_STREAMS; type++) {
-		if (cx->streams[type].dvb.enabled)
+		if (cx->streams[type].dvb.enabled) {
 			cx18_dvb_unregister(&cx->streams[type]);
+			cx->streams[type].dvb.enabled = false;
+		}
 
 		vdev = cx->streams[type].v4l2dev;
 

drivers/media/video/videodev.c

@@ -2023,7 +2023,7 @@ EXPORT_SYMBOL(video_ioctl2);
 static int get_index(struct video_device *vdev, int num)
 {
 	u32 used = 0;
-	const unsigned max_index = sizeof(used) * 8 - 1;
+	const int max_index = sizeof(used) * 8 - 1;
 	int i;
 
 	/* Currently a single v4l driver instance cannot create more than
@@ -2145,14 +2145,15 @@ int video_register_device_index(struct video_device *vfd, int type, int nr,
 	vfd->minor=i;
 
 	ret = get_index(vfd, index);
+	vfd->index = ret;
+
+	mutex_unlock(&videodev_lock);
+
 	if (ret < 0) {
 		printk(KERN_ERR "%s: get_index failed\n", __func__);
 		goto fail_minor;
 	}
 
-	vfd->index = ret;
-
-	mutex_unlock(&videodev_lock);
 	mutex_init(&vfd->lock);
 
 	/* sysfs class */