Scientific Linux Security Update : qemu-kvm on SL7.x x86_64
High Nessus Plugin ID 85072
SynopsisThe remote Scientific Linux host is missing one or more security updates.
DescriptionA heap buffer overflow flaw was found in the way QEMU's IDE subsystem handled I/O buffer access while processing certain ATAPI commands. A privileged guest user in a guest with the CDROM drive enabled could potentially use this flaw to execute arbitrary code on the host with the privileges of the host's QEMU process corresponding to the guest.
An out-of-bounds memory access flaw, leading to memory corruption or possibly an information leak, was found in QEMU's pit_ioport_read() function. A privileged guest user in a QEMU guest, which had QEMU PIT emulation enabled, could potentially, in rare cases, use this flaw to execute arbitrary code on the host with the privileges of the hosting QEMU process. (CVE-2015-3214)
This update also fixes the following bug :
- Due to an incorrect implementation of portable memory barriers, the QEMU emulator in some cases terminated unexpectedly when a virtual disk was under heavy I/O load. This update fixes the implementation in order to achieve correct synchronization between QEMU's threads.
As a result, the described crash no longer occurs.
After installing this update, shut down all running virtual machines.
Once all virtual machines have shut down, start them again for this update to take effect.
SolutionUpdate the affected packages.