Forwarded: Input: sur40: fix use-after-free on probe failure
From: syzbot
Date: Mon Aug 10 2026 - 10:19:51 EST
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Subject: Input: sur40: fix use-after-free on probe failure
Author: vasilisalmpanis@xxxxxxxxx
#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: