#7  <signal handler called>
No symbol table info available.
#8  0x000000000043f47c in cm_connect_netlogon_transport (domain=domain@entry=0x17cd180, transport=transport@entry=NCACN_IP_TCP, cli=cli@entry=0x7ffccd40ed00) at ../../source3/winbindd/winbindd_cm.c:3216
        msg_ctx = 0x171a7a0
        conn = 0x17cd2d8
        result = {v = 0}
        sec_chan_type = <optimized out>
        creds = 0x0
        remote_name = 0x0
        remote_sockaddr = 0x0
        __func__ = "cm_connect_netlogon_transport"
        __FUNCTION__ = "cm_connect_netlogon_transport"

That is in

    remote_name = smbXcli_conn_remote_name(conn->cli->conn);

For some reason conn->cli is NULL.

Problem is triggered by the client sending the DC name as domain and the DC password check code then forwards the request to winbindd.