The old stream limit checks, before 6986ddac1e, were good but
pointless for the crafted t2_strings. Checking limits there is
not necessary as they are created to hold all data. By using two
conditions, we can detect the actual crossing of the stream boundary
as appropriate for the stream pointer only. The t2_strings parsing
will not be triggering these checks.
* src/cff/cffparse.c (cff_parser_within_limits): Removed.
(cff_parse_real, cff_parse_integer): Redesign the stream limit check.
(cff_parse_num, do fixed, cff_parse_fixed_dynamic): Update callers.
4f0a55d15e