bplist: Make sure sanity checks work on 32bit platforms

Because on 32-bit platforms 32-bit pointers and 64-bit sizes have been
used for the sanity checks of the offset table and object references,
the range checks would fail in certain interger-overflowish situations,
causing heap buffer overflows or other unwanted behavior.
Fixed by wideing the operands in question to 64-bit.
1 file changed