RHSA-2015:2645: Important: kernel security and bug fix update

The kernel packages contain the Linux kernel, the core of any Linuxoperating system. It was found that the x86 ISA (Instruction Set Architecture) is prone to a denial of service attack inside a virtualized environment in the form ofan infinite loop in the microcode due to the way (sequential) delivering ofbenign exceptions such as #AC (alignment check exception) and #DB (debugexception) is handled. A privileged user inside a guest could use theseflaws to create denial of service conditions on the host kernel.(CVE-2015-5307, CVE-2015-8104, Important)Red Hat would like to thank Ben Serebrin of Google Inc. for reporting theCVE-2015-5307 issue.This update also fixes the following bugs: With an IPv6 address on a bond and a slave failover, Unsolicited Neighbor Advertisement (UNA) was previously sent using the link global IPv6 addressas source address. The underlying source code has been patched, and, afterthe failover in bonding, UNA is sent using both the corresponding link IPv6address and global IPv6 address of bond0 and bond0.vlan. (BZ#1258479) Previously, Human Interface Device (HID) would run a report on an unaligned buffer, which could cause a page fault interrupt and an oops whenthe end of the report was read. This update fixes this bug by padding theend of the report with extra bytes, so the reading of the report nevercrosses a page boundary. As a result, a page fault and subsequent oops nolonger occur. (BZ#1268201)All kernel users are advised to upgrade to these updated packages, whichcontain backported patches to correct these issues. The system must berebooted for this update to take effect.