A network device receives a packet having i) a first field that is to be updated by the network device, and ii) a second field that includes current error detection information corresponding to content of the packet, the content including the first field. The network device determines an update value that is to be added to a current value of the first field to generate a new value of the first field. The network device generates new error detection information using the current error detection information and the update value, and without using the current value of the first field. The network device modifies the second field to include the new error detection information, and modifies the first field to include the new value.