RHSA-2011:0017: Important: Red Hat Enterprise Linux 5.6 kernel security and bug fix update

The kernel packages contain the Linux kernel, the core of any Linuxoperating system.This update fixes the following security issues: A NULL pointer dereference flaw was found in the igb driver in the Linux kernel. If both the Single Root I/O Virtualization (SR-IOV) feature andpromiscuous mode were enabled on an interface using igb, it could result ina denial of service when a tagged VLAN packet is received on thatinterface. (CVE-2010-4263, Important) A missing sanity check was found in vbdcreate() in the Xen hypervisor implementation. As CD-ROM drives are not supported by the blkback back-enddriver, attempting to use a virtual CD-ROM drive with blkback could triggera denial of service (crash) on the host system running the Xen hypervisor.(CVE-2010-4238, Moderate) A flaw was found in the Linux kernel execve() system call implementation. A local, unprivileged user could cause large amounts of memory to beallocated but not visible to the OOM (Out of Memory) killer, triggering adenial of service. (CVE-2010-4243, Moderate) A flaw was found in fixuppagefault() in the Xen hypervisor implementation. If a 64-bit para-virtualized guest accessed a certain areaof memory, it could cause a denial of service on the host system runningthe Xen hypervisor. (CVE-2010-4255, Moderate) A missing initialization flaw was found in the bfa driver used by Brocade Fibre Channel Host Bus Adapters. A local, unprivileged user could use thisflaw to cause a denial of service by reading a file in the"/sys/class/fchost/host#/statistics/" directory. (CVE-2010-4343, Moderate) Missing initialization flaws in the Linux kernel could lead to information leaks. (CVE-2010-3296, CVE-2010-3877, CVE-2010-4072,CVE-2010-4073, CVE-2010-4075, CVE-2010-4080, CVE-2010-4081, CVE-2010-4158,Low)Red Hat would like to thank Kosuke Tatsukawa for reporting CVE-2010-4263;Vladymyr Denysov for reporting CVE-2010-4238; Brad Spengler for reportingCVE-2010-4243; Dan Rosenberg for reporting CVE-2010-3296, CVE-2010-4073,CVE-2010-4075, CVE-2010-4080, CVE-2010-4081, and CVE-2010-4158; VasiliyKulikov for reporting CVE-2010-3877; and Kees Cook for reportingCVE-2010-4072.These updated packages also include several hundred bug fixes for andenhancements to the Linux kernel. Space precludes documenting each of thesechanges in this advisory and users are directed to the Red Hat EnterpriseLinux 5.6 Release Notes for information on the most significant of thesechanges:http://docs.redhat.com/docs/en-US/RedHatEnterpriseLinux/5/html/5.6ReleaseNotes/index.html Refer to the kernel chapter in the Red Hat Enterprise Linux 5.6 TechnicalNotes for further information:http://docs.redhat.com/docs/en-US/RedHatEnterpriseLinux/5/html/5.6TechnicalNotes/kernel.html All Red Hat Enterprise Linux 5 users are advised to install these updatedpackages, which address these vulnerabilities as well as fixing the bugsand adding the enhancements noted in the Red Hat Enterprise Linux 5.6Release Notes and Technical Notes. The system must be rebooted for thisupdate to take effect.