libvirt: unprivileged user can crash libvirtd during spice migration

The qemuMigrationWaitForSpice function in qemu/qemumigration.c in libvirt before 1.1.3 does not properly enter a monitor when performing seamless SPICE migration, which allows local users to cause a denial of service NULL pointer dereference and libvirtd crash by causing domblkstat to be called a...