Forwarded: Input: sur40: fix use-after-free on probe failure

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Subject: Input: sur40: fix use-after-free on probe failure
Author: vasilisalmpanis@gmail.com

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git db2ddb87143519e20a95aa36c60b36107b736a58

diff --git a/drivers/input/touchscreen/sur40.c b/drivers/input/touchscreen/sur40.c
index fe63d53d56db..f28536c118aa 100644
--- a/drivers/input/touchscreen/sur40.c
+++ b/drivers/input/touchscreen/sur40.c
@@ -725,21 +725,13 @@ static int sur40_probe(struct usb_interface *interface,
 		goto err_free_input;
 	}
 
-	/* register the polled input device */
-	error = input_register_device(input);
-	if (error) {
-		dev_err(&interface->dev,
-			"Unable to register polled input device.");
-		goto err_free_buffer;
-	}
-
 	/* register the video master device */
 	snprintf(sur40->v4l2.name, sizeof(sur40->v4l2.name), "%s", DRIVER_LONG);
 	error = v4l2_device_register(sur40->dev, &sur40->v4l2);
 	if (error) {
 		dev_err(&interface->dev,
 			"Unable to register video master device.");
-		goto err_unreg_v4l2;
+		goto err_free_buffer;
 	}
 
 	/* initialize the lock and subdevice */
@@ -786,15 +778,22 @@ static int sur40_probe(struct usb_interface *interface,
 	if (sur40->hdl.error) {
 		dev_err(&interface->dev,
 			"Unable to register video controls.");
-		v4l2_ctrl_handler_free(&sur40->hdl);
 		error = sur40->hdl.error;
-		goto err_unreg_v4l2;
+		goto err_free_hdl;
 	}
 
 	error = video_register_device(&sur40->vdev, VFL_TYPE_TOUCH, -1);
 	if (error) {
 		dev_err(&interface->dev,
 			"Unable to register video subdevice.");
+		goto err_free_hdl;
+	}
+
+	/* register the polled input device */
+	error = input_register_device(input);
+	if (error) {
+		dev_err(&interface->dev,
+			"Unable to register polled input device.");
 		goto err_unreg_video;
 	}
 
@@ -806,6 +805,8 @@ static int sur40_probe(struct usb_interface *interface,
 
 err_unreg_video:
 	video_unregister_device(&sur40->vdev);
+err_free_hdl:
+	v4l2_ctrl_handler_free(&sur40->hdl);
 err_unreg_v4l2:
 	v4l2_device_unregister(&sur40->v4l2);
 err_free_buffer: