Linux: ip: Error: argument “eth12.1.0123456789“ is wrong: “name“ not a valid ifname

#ip link add link oam0 name eth12.1.0123456789 type vlan protocol 802.1Q id 3
Error: argument “eth12.1.0123456789” is wrong: “name” not a valid ifname
sig01-oam-a:root/var/log:
#ip link add link oam0 name eth12.1.01234567 type vlan protocol 802.1Q id 3
Error: argument “eth12.1.01234567” is wrong: “name” not a valid ifname
sig01-oam-a:root/var/log:
#ip link add link oam0 name eth12.1.0123456 type vlan protocol 802.1Q id 3
ip link show
7: eth12.1.0123456@oam0: mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether fa:16:3e:d8:6e:58 brd ff:ff:ff:ff:ff:ff

glibc：sysdeps/gnu/net/if.h

#define IF_NAMESIZE 16

kernel: netlink: include/uapi/linux/if.h
#if __UAPI_DEF_IF_IFNAMSIZ
#define IFNAMSIZ 16

net/ipv4/devinet.c

static size_t inet_nlmsg_size(void)
{
	return NLMSG_ALIGN(sizeof(struct ifaddrmsg))
	       + nla_total_size(4) 
	       + nla_total_size(4) 
	       + nla_total_size(4) 
	       + nla_total_size(IFNAMSIZ)     
	       + nla_total_size(4)  
	       + nla_total_size(4)  
	       + nla_total_size(sizeof(struct ifa_cacheinfo)); 
}