tools/testing/selftests/bpf/progs/sockmap_parse_prog.c

#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_endian.h>

SEC("sk_skb1")
int bpf_prog1(struct __sk_buff *skb)
{
	return skb->len;
}

char _license[] SEC("license") = "GPL";