textproc/raptor2 heap overflow

According to https://www.openwall.com/lists/oss-security/2017/06/07/1 there are
two heap overflows in raptor 2.0.15.

A CVE has been assigned:

https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2017-18926

The upstream raptor github repo has a patch:

https://github.com/dajobe/raptor/commit/590681e546cd9aa18d57dc2ea1858cb734a3863f.patch

PR: 250971
Submitted by: truckman
MFH: 2020Q4
Security: CVE-2017-18926