[LU-1511] Kernel update [RHEL5.8 2.6.18-308.11.1.el5]

• Type: Improvement
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.1.3, Lustre 1.8.9
• Assignee: Yang Sheng
• Reporter: Yang Sheng

Description

This update fixes the following security issues:

• It was found that the Xen hypervisor implementation as shipped with Red
  Hat Enterprise Linux 5 did not properly restrict the syscall return
  addresses in the sysret return path to canonical addresses. An unprivileged
  user in a 64-bit para-virtualized guest, that is running on a 64-bit host
  that has an Intel CPU, could use this flaw to crash the host or,
  potentially, escalate their privileges, allowing them to execute arbitrary
  code at the hypervisor level. (CVE-2012-0217, Important)

• It was found that guests could trigger a bug in earlier AMD CPUs, leading
  to a CPU hard lockup, when running on the Xen hypervisor implementation. An
  unprivileged user in a 64-bit para-virtualized guest could use this flaw to
  crash the host. Warning: After installing this update, hosts that are using
  an affected AMD CPU (refer to Red Hat Bugzilla bug #824966 for a list) will
  fail to boot. In order to boot such hosts, the new kernel parameter,
  allow_unsafe, can be used ("allow_unsafe=on"). This option should only be
  used with hosts that are running trusted guests, as setting it to "on"
  reintroduces the flaw (allowing guests to crash the host). (CVE-2012-2934,
  Moderate)

Note: For Red Hat Enterprise Linux guests, only privileged guest users can
exploit the CVE-2012-0217 and CVE-2012-2934 issues.

Bugs fixed (http://bugzilla.redhat.com/):

813428 - CVE-2012-0217 kernel: x86-64: avoid sysret to non-canonical address
824966 - CVE-2012-2934 kernel: denial of service due to AMD Erratum #121

Issue Links

• Trackbacks: Lustre 1.8.x known issues tracker While testing against Lustre b18 branch, we would hit known bugs which were already reported in Lustre Bugzilla https://bugzilla.lustre.org/. In order to move away from relying on Bugzilla, we would create a JIRA
• Trackbacks: Changelog 2.1 Changes from version 2.1.2 to version 2.1.3 Server support for kernels: 2.6.18308.13.1.el5 (RHEL5) 2.6.32279.2.1.el6 (RHEL6) Client support for unpatched kernels: 2.6.18308.13.1.el5 (RHEL5) 2.6.32279.2.1....