The start_thread function in arch/powerpc/kernel/process.c in the Linux kernel through 4.6.3 on powerpc platforms mishandles transactional state, which allows local users to cause a denial of service (invalid process state or TM Bad Thing exception, and system crash) or possibly have unspecified other impact by starting and suspending a transaction before an exec system call.
https://patchwork.ozlabs.org/patch/636776/
http://www.ubuntu.com/usn/USN-3071-2
http://www.ubuntu.com/usn/USN-3071-1
http://www.ubuntu.com/usn/USN-3070-4
http://www.ubuntu.com/usn/USN-3070-3
http://www.ubuntu.com/usn/USN-3070-2
http://www.ubuntu.com/usn/USN-3070-1
http://www.securityfocus.com/bid/91415
http://www.openwall.com/lists/oss-security/2016/06/25/7
http://www.debian.org/security/2016/dsa-3616
http://rhn.redhat.com/errata/RHSA-2016-2574.html
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00055.html
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00044.html
http://lists.opensuse.org/opensuse-security-announce/2016-08/msg00000.html