add CVE fixes

add CVE fixes

 CVE-2017-7539:
   qemu-nbd crashes due to undefined I/O coroutine
 CVE-2017-11434:
   slirp: out-of-bounds read while parsing dhcp options
 CVE-2017-11334:
   exec: oob access during dma operation
 CVE-2017-10806:
   usb-redirect: stack buffer overflow in debug logging
 CVE-2017-10664:
   qemu-nbd: server breaks with SIGPIPE upon client abort
 CVE-2017-9524:
   nbd: segmentation fault due to client non-negotiation
 CVE-2017-9503:
   scsi: null pointer dereference while processing megasas command