dhcp.c in dhcpcd before 7.2.1 contains a 1-byte read overflow with DHO_OPTSOVERLOADED.
https://roy.marples.name/git/dhcpcd.git/commit/?id=4b67f6f1038fd4ad5ca7734eaaeba1b2ec4816b8
https://roy.marples.name/archives/dhcpcd-discuss/0002415.html
https://lists.debian.org/debian-lts-announce/2019/05/msg00024.html