USB: legousbtower: fix use-after-free on release

commit 726b55d0e2 upstream.

The driver was accessing its struct usb_device in its release()
callback without holding a reference. This would lead to a
use-after-free whenever the device was disconnected while the character
device was still open.

Fixes: fef526cae7 ("USB: legousbtower: remove custom debug macro")
Cc: stable <stable@vger.kernel.org>     # 3.12
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191009153848.8664-5-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2019-10-09 17:38:47 +02:00 committed by Greg Kroah-Hartman
parent 2f24387c1d
commit 5f5264e0d7

View file

@ -300,6 +300,7 @@ static inline void tower_delete (struct lego_usb_tower *dev)
kfree (dev->read_buffer);
kfree (dev->interrupt_in_buffer);
kfree (dev->interrupt_out_buffer);
usb_put_dev(dev->udev);
kfree (dev);
}
@ -813,7 +814,7 @@ static int tower_probe (struct usb_interface *interface, const struct usb_device
mutex_init(&dev->lock);
dev->udev = udev;
dev->udev = usb_get_dev(udev);
dev->open_count = 0;
dev->disconnected = 0;