RHSA-2015:1778: Important: kernel security and bug fix update

The kernel packages contain the Linux kernel, the core of any Linuxoperating system. A flaw was found in the kernel's implementation of the Berkeley Packet Filter (BPF). A local attacker could craft BPF code to crash the system bycreating a situation in which the JIT compiler would fail to correctlyoptimize the JIT image on the last pass. This would lead to the CPUexecuting instructions that were not part of the JIT code. (CVE-2015-4700,Important) Two flaws were found in the way the Linux kernel's networking implementation handled UDP packets with incorrect checksum values. A remoteattacker could potentially use these flaws to trigger an infinite loop inthe kernel, resulting in a denial of service on the system, or cause adenial of service in applications using the edge triggered epollfunctionality. (CVE-2015-5364, CVE-2015-5366, Important) A flaw was found in the way the Linux kernel's ext4 file system handled the "page size > block size" condition when the fallocate zero rangefunctionality was used. A local attacker could use this flaw to crash thesystem. (CVE-2015-0275, Moderate) It was found that the Linux kernel's keyring implementation would leak memory when adding a key to a keyring via the addkey() function. A localattacker could use this flaw to exhaust all available memory on the system.(CVE-2015-1333, Moderate) A race condition flaw was found in the way the Linux kernel's SCTP implementation handled Address Configuration lists when performing AddressConfiguration Change (ASCONF). A local attacker could use this flaw tocrash the system via a race condition triggered by setting certain ASCONFoptions on a socket. (CVE-2015-3212, Moderate) An information leak flaw was found in the way the Linux kernel's Virtual Dynamic Shared Object (vDSO) implementation performed addressrandomization. A local, unprivileged user could use this flaw to leakkernel memory addresses to user-space. (CVE-2014-9585, Low)Red Hat would like to thank Daniel Borkmann for reporting CVE-2015-4700,and Canonical for reporting the CVE-2015-1333 issue. The CVE-2015-0275issue was discovered by Xiong Zhou of Red Hat, and the CVE-2015-3212 issuewas discovered by Ji Jianwen of Red Hat Engineering.This update also fixes several bugs. Refer to the following Knowledgebasearticle for further information:https://access.redhat.com/articles/1614563 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.