r0 = socket$inet6_tcp(0xa, 0x1, 0x0)
setsockopt$inet6_group_source_req(r0, 0x29, 0x2e, &(0x7f0000000080)={0x4, {{0xa, 0x0, 0x0, @mcast1}}, {{0xa, 0x0, 0x0, @dev}}}, 0x108)