RHSA-2014:0439: Important: kernel-rt security, bug fix, and enhancement update

The kernel-rt packages contain the Linux kernel, the core of any Linuxoperating system. A denial of service flaw was found in the way the Linux kernel's IPv6 implementation processed IPv6 router advertisement (RA) packets.An attacker able to send a large number of RA packets to a target systemcould potentially use this flaw to crash the target system. (CVE-2014-2309,Important) A flaw was found in the way the Linux kernel's netfilter connection tracking implementation for Datagram Congestion Control Protocol (DCCP)packets used the skbheaderpointer() function. A remote attacker could usethis flaw to send a specially crafted DCCP packet to crash the system or,potentially, escalate their privileges on the system. (CVE-2014-2523,Important) A flaw was found in the way the Linux kernel's CIFS implementation handled uncached write operations with specially crafted iovec structures.An unprivileged local user with access to a CIFS share could use this flawto crash the system, leak kernel memory, or, potentially, escalate theirprivileges on the system. (CVE-2014-0069, Moderate) A flaw was found in the way the Linux kernel handled pending Floating Pointer Unit (FPU) exceptions during the switching of tasks. A localattacker could use this flaw to terminate arbitrary processes on thesystem, causing a denial of service, or, potentially, escalate theirprivileges on the system. Note that this flaw only affected systems usingAMD CPUs on both 32-bit and 64-bit architectures. (CVE-2014-1438, Moderate) It was found that certain protocol handlers in the Linux kernel's networking implementation could set the addrlen value without initializingthe associated data structure. A local, unprivileged user could use thisflaw to leak kernel stack memory to user space using the recvmsg, recvfrom,and recvmmsg system calls. (CVE-2013-7263, CVE-2013-7265, Low) An information leak flaw was found in the Linux kernel's netfilter connection tracking IRC NAT helper implementation that could allow a remoteattacker to disclose portions of kernel stack memory during IRC DCC (DirectClient-to-Client) communication over NAT. (CVE-2014-1690, Low) A denial of service flaw was discovered in the way the Linux kernel's SELinux implementation handled files with an empty SELinux securitycontext. A local user who has the CAPMACADMIN capability could use thisflaw to crash the system. (CVE-2014-1874, Low)Red Hat would like to thank Al Viro for reporting CVE-2014-0069.The CVE-2014-1690 issue was discovered by Daniel Borkmann of Red Hat.This update also fixes several bugs and adds multiple enhancements.Documentation for these changes will be available shortly from theTechnical Notes document linked to in the References section.Users are advised to upgrade to these updated packages, which upgrade thekernel-rt kernel to version kernel-rt-3.10.33-rt32.33, correct theseissues, and fix the bugs and add the enhancements noted in the Red HatEnterprise MRG 2 Technical Notes. The system must be rebooted for thisupdate to take effect.