We need six consecutive commits backported to F17, as this set of double-close bugs can cause rather insidious failures of libvirt.

b19c236d69278c967d2d8b4aae97ac76213f1c10 qemu: avoid closing fd more than once
746ff701e8727439cac8ca72531d82e5cb7fa129 command: check for fork error before closing fd
f3cfc7c8848006b613e09bb1acd081716854527e fdstream: avoid double close bug
da831afcf2f6c0d3ed1ea3128a6208f548a05d8f command: avoid double close bugs
655cffa0f25be40c68624036af80bde102177612 avoid fd leak
0a045f01cfa48fabd41c801e3f44034a4e6da485 avoid closing uninitialized fd

Fixed in current release