# Changes in TIFF v4.0.8

References
Current Version | v4.0.8 (tag Release-v4-0-8)
Previous Version | v4.0.7
Master Download Site | https://download.osgeo.org/libtiff/
Master HTTP Site #1 | http://www.simplesystems.org/libtiff/
Master HTTP Site #2 | http://libtiff.maptools.org/

This document describes the changes made to the software between the previous and current versions (see above). If you don't find something listed here, then it was not done in this timeframe, or it was not considered important enough to be mentioned. The following information is located here:

## Major changes

- None

## Software configuration changes

- None

## Library changes

- `libtiff/tif_getimage.c`, `libtiff/tif_open.c`: add parenthesis to fix cppcheck `clarifyCalculation` warnings

- `libtiff/tif_predict.c`, `libtiff/tif_print.c`: fix printf unsigned vs signed formatting (cppcheck `invalidPrintfArgType_uint` warnings)

- `libtiff/tif_read.c`, `libtiff/tiffiop.h`: fix `uint32` overflow in `TIFFReadEncodedStrip()` that caused an integer division by zero. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2596

- `libtiff/tif_pixarlog.c`, `libtiff/tif_luv.c`: fix heap-based buffer overflow on generation of PixarLog / LUV compressed files, with `ColorMap`, `TransferFunction` attached and nasty plays with `bitspersample`. The fix for LUV has not been tested, but suffers from the same kind of issue of PixarLog. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2604

- `libtiff/tif_strip.c`: revert the change in `TIFFNumberOfStrips()` done for MapTools bugzilla #2587 / CVE-2016-9273 since the above change is a better fix that makes it unnecessary.

- `libtiff/tif_dirread.c`: modify `ChopUpSingleUncompressedStrip()` to instantiate compute `nstrips` as `TIFFhowmany_32(td->td_imagelength, rowsperstrip)`, instead of a logic based on the total size of data. Which is faulty is the total size of data is not sufficient to fill the whole image, and thus results in reading outside of the `StripByCounts`/`StripOffsets` arrays when using `TIFFReadScanline()`. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2608.

- `libtiff/tif_ojpeg.c`: make `OJPEGDecode()` early exit in case of failure in `OJPEGPreDecode()`. This will avoid a divide by zero, and potential other issues. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2611

- `libtiff/tif_write.c`: fix misleading indentation as warned by GCC.

- `libtiff/tif_fax3.h`: revert change done on 2016-01-09 that made `Param` member of `TIFFFaxTabEnt` structure a `uint16` to reduce size of the binary. It happens that the Hylafax software uses the tables that follow this typedef (`TIFFFaxMainTable`, `TIFFFaxWhiteTable`, `TIFFFaxBlackTable`), although they are not in a public libtiff header. Raised by Lee Howard. Fixes MapTools bugzilla #2636

- `libtiff/tiffio.h`, `libtiff/tif_getimage.c`: add `TIFFReadRGBAStripExt()` and `TIFFReadRGBATileExt()` variants of the functions without ext, with an extra argument to control the `stop_on_error` behaviour.

- `libtiff/tif_getimage.c`: fix potential memory leaks in error code path of `TIFFRGBAImageBegin()`. Fixes MapTools bugzilla #2627

- `libtiff/tif_jpeg.c`: increase libjpeg max memory usable to 10 MB instead of libjpeg 1MB default. This helps when creating files with "big" tile, without using libjpeg temporary files. Related to https://trac.osgeo.org/gdal/ticket/6757

- `libtiff/tif_jpeg.c`: avoid integer division by zero in `JPEGSetupEncode()` when horizontal or vertical sampling is set to 0. Fixes MapTools bugzilla #2653

- `libtiff/tif_dirwrite.c`: in `TIFFWriteDirectoryTagCheckedRational()`, replace assertion by runtime check to error out if passed value is strictly negative. Fixes MapTools bugzilla #2535

- `libtiff/tif_dirread.c`: avoid division by floating point 0 in `TIFFReadDirEntryCheckedRational()` and `TIFFReadDirEntryCheckedSrational()`, and return 0 in that case (instead of infinity as before presumably) Apparently some sanitizers do not like those divisions by zero. Fixes MapTools bugzilla #2644

- `libtiff/tif_dir.c`, `tif_dirread.c`, `tif_dirwrite.c`: implement various clampings of double to other data types to avoid undefined behaviour if the output range isn't big enough to hold the input value. Fixes MapTools bugzilla #2643, MapTools bugzilla #2642, MapTools bugzilla #2646, MapTools bugzilla #2647

- `libtiff/tif_jpeg.c`: validate `BitsPerSample` in `JPEGSetupEncode()` to avoid undefined behaviour caused by invalid shift exponent. Fixes MapTools bugzilla #2648

- `libtiff/tif_read.c`: avoid potential undefined behaviour on signed integer addition in `TIFFReadRawStrip1()` in `isMapped()` case. Fixes MapTools bugzilla #2650

- `libtiff/tif_getimage.c`: add explicit `uint32()` cast in `putagreytile` to avoid `UndefinedBehaviorSanitizer` warning. Patch by Nicolás Peña. Fixes MapTools bugzilla #2658

- `libtiff/tif_read.c`: `TIFFReadBufferSetup()`: use `_TIFFcalloc()` to zero initialize `tif_rawdata`. Fixes MapTools bugzilla #2651

- `libtiff/tiffio.h`, `tif_unix.c`, `tif_win32.c`, `tif_vms.c`: add

    `_TIFFcalloc()`

- `libtiff/tif_luv.c`, `tif_lzw.c`, `tif_packbits.c`: return 0 in Encode functions instead of -1 when `TIFFFlushData1()` fails. Fixes MapTools bugzilla #2130

- `libtiff/tif_ojpeg.c`: fix leak in `OJPEGReadHeaderInfoSecTablesQTable()`, `OJPEGReadHeaderInfoSecTablesDcTable()` and `OJPEGReadHeaderInfoSecTablesAcTable()` when read fails. Patch by Nicolás Peña. Fixes MapTools bugzilla #2659

- `libtiff/tif_jpeg.c`: only run `JPEGFixupTagsSubsampling()` if the `YCbCrSubsampling` tag is not explicitly present. This helps a bit to reduce the I/O amount when the tag is present (especially on cloud hosted files).

- `libtiff/tif_lzw.c`: in `LZWPostEncode()`, increase, if necessary, the code bit-width after flushing the remaining code and before emitting the EOI code. Fixes MapTools bugzilla #1982

- `libtiff/tif_pixarlog.c`: fix memory leak in error code path of `PixarLogSetupDecode()`. Patch by Nicolás Peña. Fixes MapTools bugzilla #2665

- `libtiff/tif_fax3.c`, `tif_predict.c`, `tif_getimage.c`: fix GCC 7 `-Wimplicit-fallthrough` warnings.

- `libtiff/tif_dirread.c`: fix memory leak in non `DEFER_STRILE_LOAD` mode (ie default) when there is both a `StripOffsets` and `TileOffsets` tag, or a `StripByteCounts` and `TileByteCounts`. Fixes MapTools bugzilla #2689

- `libtiff/tif_ojpeg.c`: fix potential memory leak in `OJPEGReadHeaderInfoSecTablesQTable()`, `OJPEGReadHeaderInfoSecTablesDcTable()` and `OJPEGReadHeaderInfoSecTablesAcTable()`. Patch by Nicolás Peña. Fixes MapTools bugzilla #2670

- `libtiff/tif_fax3.c`: avoid crash in `Fax3Close()` on empty file. Patch by Alan Coopersmith + complement by myself. Fixes MapTools bugzilla #2673

- `libtiff/tif_read.c`: `TIFFFillStrip()`: add limitation to the number of bytes read in case `td_stripbytecount[strip]` is bigger than reasonable, so as to avoid excessive memory allocation.

- `libtiff/tif_zip.c`, `tif_pixarlog.c`, `tif_predict.c`: fix memory leak when the underlying codec (ZIP, PixarLog) succeeds its `setupdecode()` method, but `PredictorSetup()` fails. Credit to OSS-Fuzz (locally run, on GDAL)

- `libtiff/tif_read.c`: `TIFFFillStrip()` and `TIFFFillTile()`: avoid excessive memory allocation in case of shorten files. Only effective on 64 bit builds and non-mapped cases. Credit to OSS-Fuzz (locally run, on GDAL)

- `libtiff/tif_read.c`: `TIFFFillStripPartial()` / `TIFFSeek()`, avoid potential integer overflows with read_ahead in `CHUNKY_STRIP_READ_SUPPORT` mode. Should especially occur on 32 bit platforms.

- `libtiff/tif_read.c`: `TIFFFillStripPartial()`: avoid excessive memory allocation in case of shorten files. Only effective on 64 bit builds. Credit to OSS-Fuzz (locally run, on GDAL)

- `libtiff/tif_read.c`: update `tif_rawcc` in `CHUNKY_STRIP_READ_SUPPORT` mode with `tif_rawdataloaded` when calling `TIFFStartStrip()` or `TIFFFillStripPartial()`. This avoids reading beyond `tif_rawdata()` when `bytecount > tif_rawdatasize`. Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=1545. Credit to OSS-Fuzz

- `libtiff/tif_color.c`: avoid potential `int32` overflow in `TIFFYCbCrToRGBInit()`. Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=1533 Credit to OSS-Fuzz

- `libtiff/tif_pixarlog.c`, `tif_luv.c`: avoid potential `int32` overflows in `multiply_ms()` and `add_ms()`. Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=1558 Credit to OSS-Fuzz

- `libtiff/tif_packbits.c`: fix out-of-buffer read in `PackBitsDecode()`. Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=1563 Credit to OSS-Fuzz

- `libtiff/tif_luv.c`: `LogL16InitState()`: avoid excessive memory allocation when `RowsPerStrip` tag is missing. Credit to OSS-Fuzz (locally run, on GDAL)

- `libtiff/tif_lzw.c`: update dec_bitsleft at beginning of LZWDecode(), and update tif_rawcc at end of LZWDecode(). This is needed to properly work with the latest chnges in tif_read.c in CHUNKY_STRIP_READ_SUPPORT mode.

- `libtiff/tif_pixarlog.c`: `PixarLogDecode()`: resync `tif_rawcp` with `next_in` and `tif_rawcc` with `avail_in` at beginning and end of function, similarly to what is done in `LZWDecode()`. Likely needed so that it works properly with latest chnges in `tif_read.c` in `CHUNKY_STRIP_READ_SUPPORT` mode. But untested...

- `libtiff/tif_getimage.c`: `initYCbCrConversion()`: add basic validation of `luma` and `refBlackWhite` coefficients (just check they are not NaN for now), to avoid potential float to int overflows. Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=1663 Credit to OSS Fuzz

- `libtiff/tif_read.c`: `_TIFFVSetField()`: fix outside range cast of double to float. Credit to Google Autofuzz project

- `libtiff/tif_getimage.c`: `initYCbCrConversion()`: check `luma[1]` is not zero to avoid division by zero. Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=1665 Credit to OSS Fuzz

- `libtiff/tif_read.c`: `_TIFFVSetField()`: fix outside range cast of double to float. Credit to Google Autofuzz project

- `libtiff/tif_getimage.c`: `initYCbCrConversion()`: check `luma[1]` is not zero to avoid division by zero. Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=1665 Credit to OSS Fuzz

- `libtiff/tif_getimage.c`: `initYCbCrConversion()`: stricter validation for `refBlackWhite` coefficients values. To avoid invalid float to int32 conversion. Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=1718 Credit to OSS Fuzz

## Tools changes

- `tools/fax2tiff.c` (`main()`): Applied patch by Jörg Ahrens to fix passing client data for Win32 builds using `tif_win32.c` (`USE_WIN32_FILEIO` defined) for file I/O. Patch was provided via email on November 20, 2016.

- `tools/tiffcp.c`: avoid `uint32` underflow in `cpDecodedStrips()` that can cause various issues, such as buffer overflows in the library. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2598

- `tools/tiffcrop.c`: fix `readContigStripsIntoBuffer()` in `-i` (ignore) mode so that the output buffer is correctly incremented to avoid write outside bounds. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2620

- `tools/tiffcrop.c`: add 3 extra bytes at end of strip buffer in `readSeparateStripsIntoBuffer()` to avoid read outside of heap allocated buffer. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2621

- `tools/tiffcrop.c`: fix integer division by zero when `BitsPerSample` is missing. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2619

- `tools/tiffinfo.c`: fix null pointer dereference in `-r` mode when the image has no `StripByteCount` tag. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2594

- `tools/tiffcp.c`: avoid potential division by zero if `BitsPerSamples` tag is missing. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2597

- `tools/tif_dir.c`: when `TIFFGetField(, TIFFTAG_NUMBEROFINKS, )` is called, limit the return number of inks to `SamplesPerPixel`, so that code that parses ink names doesn't go past the end of the buffer. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2599

- `tools/tiffcp.c`: avoid potential division by zero if `BitsPerSamples` tag is missing. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2607

- `tools/tiffcp.c`: fix `uint32` underflow/overflow that can cause heap-based buffer overflow. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2610

- `tools/tiffcp.c`: replace `assert( (bps % 8) == 0 )` by a non assert check. Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2605

- `tools/tiff2ps.c`: fix 2 heap-based buffer overflows (in `PSDataBW()` and `PSDataColorContig()`). Reported by Agostino Sarubbo. Fixes MapTools bugzilla #2633 and MapTools bugzilla #2634.

- `tools/tiff2pdf.c`: prevent heap-based buffer overflow in `-j` mode on a paletted image. Note: this fix errors out before the overflow happens. There could probably be a better fix. Fixes MapTools bugzilla #2635

- `tools/tiff2pdf.c`: fix wrong usage of `memcpy()` that can trigger unspecified behaviour. Fixes MapTools bugzilla #2638

- `tools/tiff2pdf.c`: avoid potential invalid memory read in `t2p_writeproc()`. Fixes MapTools bugzilla #2639

- `tools/tiff2pdf.c`: avoid potential heap-based overflow in `t2p_readwrite_pdf_image_tile()`. Fixes MapTools bugzilla #2640

- `tools/tiffcrop.c`: remove extraneous `TIFFClose()` in error code path, that caused double free. Related to MapTools bugzilla #2535

- `tools/tiffcp.c`: error out cleanly in `cpContig2SeparateByRow()` and `cpSeparate2ContigByRow()` if `BitsPerSample != 8` to avoid heap based overflow. Fixes MapTools bugzilla #2656 and MapTools bugzilla #2657

- `tools/raw2tiff.c`: avoid integer division by zero. Fixes MapTools bugzilla #2631

- `tools/tiff2ps.c`: call `TIFFClose()` in error code paths.

- `tools/fax2tiff.c`: emit appropriate message if the input file is empty. Patch by Alan Coopersmith. Fixes MapTools bugzilla #2672

- `tools/tiff2bw.c`: close `TIFF` handle in error code path. Fixes MapTools bugzilla #2677

## Contributed software changes

None