Memory leak in the v9fs_link function in hw/9pfs/9p.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (memory consumption) via vectors involving a reference to the source fid object.
http://lists.opensuse.org/opensuse-updates/2016-12/msg00140.html
https://lists.debian.org/debian-lts-announce/2018/11/msg00038.html
https://lists.gnu.org/archive/html/qemu-devel/2016-10/msg02608.html
https://security.gentoo.org/glsa/201611-11