An issue was discovered in the Linux kernel before 4.8. Incorrect access checking in overlayfs mounts could be used by local attackers to modify or truncate files in the underlying filesystem.
https://support.f5.com/csp/article/K22691834
https://security.netapp.com/advisory/ntap-20190204-0001/
https://seclists.org/bugtraq/2019/Jul/33
https://bugzilla.suse.com/show_bug.cgi?id=1106512
http://www.securityfocus.com/bid/105394
http://lists.opensuse.org/opensuse-security-announce/2018-10/msg00033.html