Updated kernel packages fix security vulnerabilities

This kernel update is based on upstream -longterm 3.14.23 and fixes the following security issues: The kvm_iommu_map_pages function in virt/kvm/iommu.c in the Linux kernel through 3.16.1 miscalculates the number of pages during the handling of a mapping failure, which allows guest OS users to (1) cause a denial of service (host OS memory corruption) or possibly have unspecified other impact by triggering a large gfn value or (2) cause a denial of service (host OS memory consumption) by triggering a small gfn value that leads to permanently pinned pages (CVE-2014-3601). The assoc_array_gc function in the associative-array implementation in lib/assoc_array.c in the Linux kernel before 3.16.3 does not properly implement garbage collection, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via multiple “keyctl newring” operations followed by a “keyctl timeout” operation (CVE-2014-3631). The pivot_root implementation in fs/namespace.c in the Linux kernel through 3.17 does not properly interact with certain locations of a chroot directory, which allows local users to cause a denial of service (mount-tree loop) via . (dot) values in both arguments to the pivot_root system call (CVE-2014-7970). The do_umount function in fs/namespace.c in the Linux kernel through 3.17 does not require the CAP_SYS_ADMIN capability for do_remount_sb calls that change the root filesystem to read-only, which allows local users to cause a denial of service (loss of writability) by making certain unshare system calls, clearing the / MNT_LOCKED flag, and making an MNT_FORCE umount system call (CVE-2014-7975). Other fixes: The X86_SYSFB config option has been disabled as it prevents proper KMS setup on some systems (mga#13098) The cpupower default governor has been switched from ondemand to performance as the intel_pstate driver (used on newer Intel cpus) does not support ondemand target. For other fixes included in this update, read the referenced changelogs.