In the Linux kernel through 5.2.14 on the powerpc platform, a local user can read vector registers of other users’ processes via an interrupt. To exploit the venerability, a local user starts a transaction (via the hardware transactional memory instruction tbegin) and then accesses vector registers. At some point, the vector registers will be corrupted with the values from a different local Linux process, because MSR_TM_ACTIVE is misused in arch/powerpc/kernel/process.c.
lists.opensuse.org/opensuse-security-announce/2019-09/msg00064.html
lists.opensuse.org/opensuse-security-announce/2019-09/msg00066.html
www.openwall.com/lists/oss-security/2019/09/10/4
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a8318c13e79badb92bc6640704a64cc022a6eb97
security.netapp.com/advisory/ntap-20191004-0001/
usn.ubuntu.com/4135-1/
usn.ubuntu.com/4135-2/