In the Linux kernel, the following vulnerability has been resolved:
ax25: Fix reference count leak issue of net_device
There is a reference count leak issue of the object "netdevice" in ax25devdevicedown(). When the ax25 device is shutting down, the ax25devdevicedown() drops the reference count of netdevice one or zero times depending on if we goto unlock_put or not, which will cause memory leak.
In order to solve the above issue, decrease the reference count of netdevice after dev->ax25ptr is set to null.