Description of problem: Structures kvm_vcpu_events, kvm_debugregs, kvm_pit_state2 and kvm_clock_data are copied to userland with some padding and reserved fields unitialized. It leads to leaking of contents of kernel stack memory. Reference: http://www.spinics.net/lists/kvm/msg44130.html http://git.kernel.org/?p=virt/kvm/kvm.git;a=commit;h=831d9d02f9522e739825a51a11e3bc5aa531a905 Acknowledgements: Red Hat would like to thank Vasiliy Kulikov of Openwall for reporting this issue.
Statement: This issue did not affect the version of Linux kernel as shipped with Red Hat Enterprise Linux 3, 4 and Red Hat Enterprise MRG as they did not include support for Kernel-based Virtual Machine (KVM). A future kernel update in Red Hat Enterprise Linux 5 may address this flaw.
Upstream commit: http://git.kernel.org/linus/97e69aa62f8b5d338d6cff49be09e37cc1262838
This issue has been addressed in following products: Red Hat Enterprise Linux 5 Via RHSA-2010:0998 https://rhn.redhat.com/errata/RHSA-2010-0998.html
This issue has been addressed in following products: Red Hat Enterprise Linux 6.0.Z - Server Only Via RHSA-2011:0883 https://rhn.redhat.com/errata/RHSA-2011-0883.html