Integer-overflow in FoFiBase::checkRegion

oss-fuzz/8612

fofi/FoFiBase.cc

@@ -17,6 +17,7 @@
 // Copyright (C) 2011 Jim Meyering <jim@meyering.net>
 // Copyright (C) 2016, 2018 Albert Astals Cid <aacid@kde.org>
 // Copyright (C) 2019 Christian Persch <chpe@src.gnome.org>
+// Copyright (C) 2019 LE GARREC Vincent <legarrec.vincent@gmail.com>
 //
 // To see a description of the changes please see the Changelog file that
 // came with your tarball or type make ChangeLog if you are building from git
@@ -195,6 +196,7 @@ unsigned int FoFiBase::getUVarBE(int pos, int size, bool *ok) const {
 
 bool FoFiBase::checkRegion(int pos, int size) const {
   return pos >= 0 &&
+         size >= 0 &&
          pos < INT_MAX - size &&
          size < INT_MAX - pos &&
          pos + size >= pos &&