The (1) v9fs_create and (2) v9fs_lcreate functions in hw/9pfs/9p.c in QEMU (aka Quick Emulator) allow local guest OS privileged users to cause a denial of service (file descriptor or memory consumption) via vectors related to an already in-use fid.
git.qemu-project.org/?p=qemu.git%3Ba=commit%3Bh=d63fb193e71644a073b77ff5ac6f1216f2f6cf6e
www.openwall.com/lists/oss-security/2017/04/03/2
www.securityfocus.com/bid/97319
bugzilla.redhat.com/show_bug.cgi?id=1437871
lists.debian.org/debian-lts-announce/2018/09/msg00007.html
lists.gnu.org/archive/html/qemu-devel/2017-03/msg05449.html
security.gentoo.org/glsa/201706-03