Vulnerability Database

In the Linux kernel, the following vulnerability has been resolved:

usbnet: Prevents free active kevent

The root cause of this issue are:

1. When probing the usbnet device, executing usbnet_link_change(dev, 0, 0); put the kevent work in global workqueue. However, the kevent has not yet been scheduled when the usbnet device is unregistered. Therefore, executing free_netdev() results in the "free active object (kevent)" error reported here.

2. Another factor is that when calling usbnet_disconnect()->unregister_netdev(), if the usbnet device is up, ndo_stop() is executed to cancel the kevent. However, because the device is not up, ndo_stop() is not executed.

The solution to this problem is to cancel the kevent before executing free_netdev().