In the Linux kernel through 5.2.14 on the powerpc platform,...

Vulnerability Description

In the Linux kernel through 5.2.14 on the powerpc platform, a local user can read vector registers of other users' processes via a Facility Unavailable exception. 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 of a missing arch/powerpc/kernel/process.c check.

References

• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=8205d5d98ef7f155de211f5e2eb6ca03d95a5a60
• http://www.openwall.com/lists/oss-security/2019/09/10/3
• https://usn.ubuntu.com/4135-2/
• http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00064.html
• http://lists.opensuse.org/opensuse-security-announce/2019-09/msg00066.html
• https://usn.ubuntu.com/4135-1/
• https://security.netapp.com/advisory/ntap-20191004-0001/
• https://access.redhat.com/errata/RHSA-2020:0740