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eliets2
555eb4c9fd
max_ifds (1024) x max_entries (8192) tables that overlap in the file — SubIFD pointers
shifted by one entry reuse the same bytes — could make Tiff::parse allocate ~8M Entry values
(~400 MB) from a ~100 KB input, since count-0 entries cost nothing from the value budget and
only the per-IFD entry cap existed. ParseOptions gains max_entries_total (65 536 default,
generous for real scanned TIFFs), charged per IFD before the entries Vec is allocated, so a
hostile file stops with TiffError::Limit("entry count") instead of amplifying.
Tests: a hostile overlapping-table chain stops after 8 IFDs inside one parse, and a
legitimate multi-IFD file (chain + Exif/GPS children) still parses fully.