When using the Triple Speed Ethernet (TSE) IP, rx_err[2] (CRC Error) and rx_err[1] (Invalid length error) can assert at the same time. These two signals are not mutually exclusive and this is the expected behaviour.
Rx_err[2] (CRC Error) should be ignored if asserted at the same time as rx_err[1] (Invalid length error), as the CRC error only applies to frames with a valid length.
This behaviour affects all versions of the TSE IP in all device families.
This behaviour is not a bug, and hence will not be fixed or addressed in a future version of the TSE software release.