The net_tx_pkt_do_sw_fragmentation function in hw/net/net_tx_pkt.c in QEMU (aka Quick Emulator) allows local guest OS administrators to cause a denial of service (infinite loop and QEMU process crash) via a zero length for the current fragment length.
https://lists.debian.org/debian-lts-announce/2018/11/msg00038.html
https://lists.gnu.org/archive/html/qemu-devel/2016-08/msg01601.html
https://security.gentoo.org/glsa/201609-01