TCP_CSUM_OFF       31 samples/bpf/tcbpf1_kern.c #define TCP_CSUM_OFF (ETH_HLEN + sizeof(struct iphdr) + offsetof(struct tcphdr, check))
TCP_CSUM_OFF       88 samples/bpf/test_lwt_bpf.c #define TCP_CSUM_OFF offsetof(struct tcphdr, check)