The filesystem layer in the Linux kernel before 4.5.5 proceeds with post-rename operations after an OverlayFS file is renamed to a self-hardlink, which allows local users to cause a denial of service (system crash) via a rename system call, related to fs/namei.c and fs/open.c.
https://github.com/torvalds/linux/commit/9409e22acdfc9153f88d9b1ed2bd2a5b34d2d3ca
https://github.com/torvalds/linux/commit/54d5ca871e72f2bb172ec9323497f01cd5091ec7
https://bugzilla.redhat.com/show_bug.cgi?id=1355654
http://www.securitytracker.com/id/1036273
http://www.securityfocus.com/bid/91709
http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html
http://www.oracle.com/technetwork/topics/security/linuxbulletinjul2016-3090544.html
http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.5.5
http://rhn.redhat.com/errata/RHSA-2016-2584.html
http://rhn.redhat.com/errata/RHSA-2016-2574.html
http://rhn.redhat.com/errata/RHSA-2016-1875.html