RHSA-2011:1479: Important: kernel security, bug fix, and enhancement update

The kernel packages contain the Linux kernel, the core of any Linuxoperating system.This update fixes the following security issues: Using PCI passthrough without interrupt remapping support allowed Xen hypervisor guests to generate MSI interrupts and thus potentially injecttraps. A privileged guest user could use this flaw to crash the host orpossibly escalate their privileges on the host. The fix for this issue canprevent PCI passthrough working and guests starting. Refer to Red HatBugzilla bug 715555 for details. (CVE-2011-1898, Important) A flaw was found in the way CIFS (Common Internet File System) shares with DFS referrals at their root were handled. An attacker on the localnetwork who is able to deploy a malicious CIFS server could create a CIFSnetwork share that, when mounted, would cause the client system to crash.(CVE-2011-3363, Moderate) A NULL pointer dereference flaw was found in the way the Linux kernel's key management facility handled user-defined key types. A local,unprivileged user could use the keyctl utility to cause a denial ofservice. (CVE-2011-4110, Moderate) A flaw in the way memory containing security-related data was handled in tpmread() could allow a local, unprivileged user to read the results of apreviously run TPM command. (CVE-2011-1162, Low) A NULL pointer dereference flaw was found in the Linux kernel's HFS file system implementation. A local attacker could use this flaw to cause adenial of service by mounting a disk that contains a specially-crafted HFSfile system with a corrupted MDB extent record. (CVE-2011-2203, Low) The I/O statistics from the taskstats subsystem could be read without any restrictions. A local, unprivileged user could use this flaw to gatherconfidential information, such as the length of a password used in aprocess. (CVE-2011-2494, Low)Red Hat would like to thank Yogesh Sharma for reporting CVE-2011-3363;Peter Huewe for reporting CVE-2011-1162; Clement Lecigne for reportingCVE-2011-2203; and Vasiliy Kulikov of Openwall for reporting CVE-2011-2494.This update also fixes several bugs and adds one enhancement. Documentationfor these changes will be available shortly from the Technical Notesdocument linked to in the References section.Users should upgrade to these updated packages, which contain backportedpatches to correct these issues, and fix the bugs and add the enhancementnoted in the Technical Notes. The system must be rebooted for this updateto take effect.