From: Johan Hovold johan@kernel.org
commit 726b55d0e22ca72c69c947af87785c830289ddbc 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: fef526cae700 ("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
--- drivers/usb/misc/legousbtower.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/usb/misc/legousbtower.c +++ b/drivers/usb/misc/legousbtower.c @@ -302,6 +302,7 @@ static inline void tower_delete (struct kfree (dev->read_buffer); kfree (dev->interrupt_in_buffer); kfree (dev->interrupt_out_buffer); + usb_put_dev(dev->udev); kfree (dev); }
@@ -820,7 +821,7 @@ static int tower_probe (struct usb_inter
mutex_init(&dev->lock);
- dev->udev = udev; + dev->udev = usb_get_dev(udev); dev->open_count = 0; dev->disconnected = 0;