[PATCH v2] media: msi2500: fix memory leak in msi2500_probe error path

[PATCH v2] media: msi2500: fix memory leak in msi2500_probe error path

[Daiki Harada]

When video_register_device() fails in msi2500_probe(), the error path
jumps to err_unregister_v4l2_dev, which skips the call to
v4l2_ctrl_handler_free(). This leaks memory allocated by
v4l2_ctrl_handler_init() and v4l2_ctrl_add_handler().

This bug was introduced when commit 2e68f841a5d1 ("[media] msi3101:
use msi001 tuner driver") reordered the cleanup labels, placing
err_free_controls above err_unregister_v4l2_dev, but did not update
the goto target in the video_register_device() failure path.

Fix this by jumping to err_free_controls instead, which properly frees
the control handler before unregistering the v4l2 device.

Reported-by: syzbot+b1de0d5fd8a15fac11aa@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=b1de0d5fd8a15fac11aa
Fixes: 2e68f841a5d1 ("[media] msi3101: use msi001 tuner driver")
Tested-by: syzbot+b1de0d5fd8a15fac11aa@syzkaller.appspotmail.com
Signed-off-by: Daiki Harada <daiky0325@gmail.com>
---
 drivers/media/usb/msi2500/msi2500.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/usb/msi2500/msi2500.c b/drivers/media/usb/msi2500/msi2500.c
index 1ff98956b680..76e1f2bfab0c 100644
--- a/drivers/media/usb/msi2500/msi2500.c
+++ b/drivers/media/usb/msi2500/msi2500.c
@@ -1265,7 +1265,7 @@ static int msi2500_probe(struct usb_interface *intf,
 	if (ret) {
 		dev_err(dev->dev,
 			"Failed to register as video device (%d)\n", ret);
-		goto err_unregister_v4l2_dev;
+		goto err_free_controls;
 	}
 	dev_info(dev->dev, "Registered as %s\n",
 		 video_device_node_name(&dev->vdev));
-- 
2.54.0