[PATCH v2] media: rockchip/rga: fix potential use after free

[Pan Bian]

The variable vga->vfd is an alias for vfd. Therefore, releasing vfd and
then unregister vga->vfd will lead to a use after free bug. In fact, the
free operation and the unregister operation are reversed.

Signed-off-by: Pan Bian <bianpan2016@xxxxxxx>
---
v2: update the goto label names consistently
---
 drivers/media/platform/rockchip/rga/rga.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/media/platform/rockchip/rga/rga.c b/drivers/media/platform/rockchip/rga/rga.c
index e9ff12b6b5bb..d2297abafc69 100644
--- a/drivers/media/platform/rockchip/rga/rga.c
+++ b/drivers/media/platform/rockchip/rga/rga.c
@@ -863,7 +863,7 @@ static int rga_probe(struct platform_device *pdev)
 	if (IS_ERR(rga->m2m_dev)) {
 		v4l2_err(&rga->v4l2_dev, "Failed to init mem2mem device\n");
 		ret = PTR_ERR(rga->m2m_dev);
-		goto unreg_video_dev;
+		goto rel_vdev;
 	}
 
 	pm_runtime_get_sync(rga->dev);
@@ -892,7 +892,7 @@ static int rga_probe(struct platform_device *pdev)
 	ret = video_register_device(vfd, VFL_TYPE_GRABBER, -1);
 	if (ret) {
 		v4l2_err(&rga->v4l2_dev, "Failed to register video device\n");
-		goto rel_vdev;
+		goto unreg_dev;
 	}
 
 	v4l2_info(&rga->v4l2_dev, "Registered %s as /dev/%s\n",
@@ -900,10 +900,10 @@ static int rga_probe(struct platform_device *pdev)
 
 	return 0;
 
+unreg_dev:
+	video_unregister_device(rga->vfd);
 rel_vdev:
 	video_device_release(vfd);
-unreg_video_dev:
-	video_unregister_device(rga->vfd);
 unreg_v4l2_dev:
 	v4l2_device_unregister(&rga->v4l2_dev);
 err_put_clk:
-- 
2.7.4