//UDP checksum is optional over IPv4 but mandatory for IPv6
//We do not check udp->length sanity but use our safe computed value instead
- if (PREDICT_FALSE (!checksum))
+ if (PREDICT_FALSE (!*checksum))
{
u16 udp_len = clib_host_to_net_u16 (ip4->length) - sizeof (*ip4);
csum = ip_incremental_checksum (0, udp, udp_len);