CVE-2021-46916

In the Linux kernel, the following vulnerability has been resolved: ixgbe:
Fix NULL pointer dereference in ethtool loopback test The ixgbe driver
currently generates a NULL pointer dereference when performing the ethtool
loopback test. This is due to the fact that there isn’t a q_vector
associated with the test ring when it is setup as interrupts are not
normally added to the test rings. To address this I have added code that
will check for a q_vector before returning a napi_id value. If a q_vector
is not present it will return a value of 0.