r0 = socket$inet6_udp(0xa, 0x2, 0x0)
sendmsg$inet6(r0, &(0x7f00000027c0)={&(0x7f0000000200)={0xa, 0x4e24, 0x0, @mcast1, 0x3}, 0x1c, 0x0}, 0x0)