From: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> commit cf7f34777a5b4100a3a44ff95f3d949c62892bdd upstream. Prevent NULL (or close to NULL) pointer dereference in various places by registering the video device only when the V4L2 m2m framework has been set up. Fixes: commit 96d8eab5d0a1 ("V4L/DVB: [v5,2/2] v4l: Add a mem-to-mem videobuf framework test device") Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx> Signed-off-by: Mark-PK Tsai <mark-pk.tsai@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/media/test-drivers/vim2m.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) --- a/drivers/media/test-drivers/vim2m.c +++ b/drivers/media/test-drivers/vim2m.c @@ -1325,12 +1325,6 @@ static int vim2m_probe(struct platform_d vfd->lock = &dev->dev_mutex; vfd->v4l2_dev = &dev->v4l2_dev; - ret = video_register_device(vfd, VFL_TYPE_VIDEO, 0); - if (ret) { - v4l2_err(&dev->v4l2_dev, "Failed to register video device\n"); - goto error_v4l2; - } - video_set_drvdata(vfd, dev); v4l2_info(&dev->v4l2_dev, "Device registered as /dev/video%d\n", vfd->num); @@ -1345,6 +1339,12 @@ static int vim2m_probe(struct platform_d goto error_dev; } + ret = video_register_device(vfd, VFL_TYPE_VIDEO, 0); + if (ret) { + v4l2_err(&dev->v4l2_dev, "Failed to register video device\n"); + goto error_m2m; + } + #ifdef CONFIG_MEDIA_CONTROLLER dev->mdev.dev = &pdev->dev; strscpy(dev->mdev.model, "vim2m", sizeof(dev->mdev.model)); @@ -1358,7 +1358,7 @@ static int vim2m_probe(struct platform_d MEDIA_ENT_F_PROC_VIDEO_SCALER); if (ret) { v4l2_err(&dev->v4l2_dev, "Failed to init mem2mem media controller\n"); - goto error_dev; + goto error_v4l2; } ret = media_device_register(&dev->mdev); @@ -1373,11 +1373,13 @@ static int vim2m_probe(struct platform_d error_m2m_mc: v4l2_m2m_unregister_media_controller(dev->m2m_dev); #endif -error_dev: +error_v4l2: video_unregister_device(&dev->vfd); /* vim2m_device_release called by video_unregister_device to release various objects */ return ret; -error_v4l2: +error_m2m: + v4l2_m2m_release(dev->m2m_dev); +error_dev: v4l2_device_unregister(&dev->v4l2_dev); error_free: kfree(dev);