r0 = socket$inet6_udp(0xa, 0x2, 0x0)
ioctl$sock_inet6_SIOCADDRT(r0, 0x890b, &(0x7f0000000280)={@private0, @initdev={0xfe, 0x88, '\x00', 0x0, 0x0}, @mcast1, 0x0, 0x178})