media: v4l: event: Prevent freeing event subscriptions while accessed

[linux.git] / drivers / media / v4l2-core / v4l2-fh.c

diff --git a/drivers/media/v4l2-core/v4l2-fh.c b/drivers/media/v4l2-core/v4l2-fh.c
index 3895999bf8805c3c208a4f042cb59b786a6ec44c..c91a7bd3ecfc7d14853b56a8de273d35ac0ff870 100644 (file)
--- a/drivers/media/v4l2-core/v4l2-fh.c
+++ b/drivers/media/v4l2-core/v4l2-fh.c
@@ -45,6 +45,7 @@ void v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev)
        INIT_LIST_HEAD(&fh->available);
        INIT_LIST_HEAD(&fh->subscribed);
        fh->sequence = -1;
+       mutex_init(&fh->subscribe_lock);
 }
 EXPORT_SYMBOL_GPL(v4l2_fh_init);
 
@@ -90,6 +91,7 @@ void v4l2_fh_exit(struct v4l2_fh *fh)
                return;
        v4l_disable_media_source(fh->vdev);
        v4l2_event_unsubscribe_all(fh);
+       mutex_destroy(&fh->subscribe_lock);
        fh->vdev = NULL;
 }
 EXPORT_SYMBOL_GPL(v4l2_fh_exit);