r0 = socket$inet6_tcp(0xa, 0x1, 0x0)
setsockopt$inet6_tcp_TCP_CONGESTION(0xffffffffffffffff, 0x6, 0xd, 0x0, 0x0)
connect$inet6(r0, &(0x7f0000000080)={0xa, 0x0, 0x0, @ipv4={'\x00', '\xff\xff', @local}}, 0x1c)