RHSA-2018:2763: Important: kernel-rt security and bug fix update

The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.Security Fix(es): kernel: Integer overflow in Linux's createelftables function (CVE-2018-14634) For more details about the security issue(s), including the impact, a CVSS score, and other related information, refer to the CVE page(s) listed in the References section.Red Hat would like to thank Qualys Research Labs for reporting this issue.Bug Fix(es): The kernel-rt packages have been upgraded to the 3.10.0-862.14.3 source tree, which provides a number of bug fixes over the previous version. (BZ#1616429) Previously, preemption was enabled too early after a context switch. If a task was migrated to another CPU after a context switch, a mismatch between CPU and runqueue during load balancing sometimes occurred. Consequently, a runnable task on an idle CPU failed to run, and the operating system became unresponsive. This update disables preemption in the scheduletail() function. As a result, CPU migration during post-schedule processing no longer occurs, which prevents the above mismatch. The operating system no longer hangs due to this bug. (BZ#1617941)