CVE-2020-11669

A flaw was found in the way Linux kernel running on the Power9 processor saves and restores its registers while going in and coming out of an idle state. The issue occurs when a guest kernel has Kernel Userspace Address Protection (KUAP) feature enabled. The idle_book3s function does not save and restore the Authority Mask Register (AMR), Authority Mask Override Register (AMOR) and User Authority Mask Override Register (UAMOR). A guest user may use this flaw to render the host system unusable resulting in DoS issue.

This issue does not affect the versions of the kernel package as shipped with the Red Hat Enterprise Linux 5, 6, 7, 8 and Red Hat Enterprise MRG 2.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.