2022.12.11 12:22 "Re: [Tiff] libtiff v4.5.0 release candidate available", by Christoph Gohlke
Using tiff-4.5.0rc1, I get a test error in the imagecodecs Python library trying to read 65535 pages/IFDs from a multi-page TIFF, which worked with libtiff-4.4.
The issue seems to be an uint16 overflow of `tif->tif_curdir` in `TIFFReadDirectory` at <https://gitlab.com/libtiff/libtiff/-/blob/master/libtiff/tif_dirread.c#L4078> when `TIFFSetDirectory(tif, 65534)` is followed by `TIFFSetDirectory(tif, 0)`. In that case libtiff returns a warning and an error:
"TIFFReadDirectory: Warning, Didn't read next directory due to IFD looping at offset 0xa7ff1e (11009822) to offset 0x8 (8)."
Error: "Cannot handle more than 65535 TIFF directories"
The test file at <https://github.com/cgohlke/imagecodecs/blob/master/tests/tiff/gray.movie.u2.tif> contains 65567 pages.