Added ImageSourceData to TAGS_V2

[radarhere]

In #7008, two images were reported to cause a RuntimeError. Testing on my machine, I found that this caused a segfault instead.

It turns out that this was due to an incorrect tag type being used for ImageSourceData.

Except then I found the RuntimeError, happening on 32-bit Windows.

E       RuntimeError: Error setting from dictionary

C:\hostedtoolcache\windows\Python\3.7.9\x86\lib\site-packages\pillow-9.5.0.dev0-py3.7-win32.egg\PIL\Image.py:437: RuntimeError
---------------------------- Captured stderr call -----------------------------
_TIFFVSetField: C:\Users\runneradmin\AppData\Local\Temp\pytest-of-runneradmin\pytest-0\test_save_imagesourcedata0\temp.tif: Bad LONG8 or IFD8 value 1000052142389717520 for "EXIFIFDOffset" tag 34665 in ClassicTIFF. Tag won't be written to file.

When it states 'Bad LONG8 or IFD8 value 1000052142389717520 for "EXIFIFDOffset" tag 34665', that number wasn't the value being passed through for the EXIF IFD offset from Python. When we are about to pass the value through to libtiff in C, we cast it to UINT32.

Pillow/src/encode.c

Lines 906 to 907 in 3166901

	status = ImagingLibTiffSetField(
	&encoder->state, (ttag_t)key_int, (UINT32)PyLong_AsLong(value));

When libtiff is throwing the error, the variable is uint64_t. Changing UINT32 to uint64_t fixed the RunTimeError.

[nulano]

I don't fully understand this change and can't look into it right now (I'm not sure why the TIFF_LONG8 error was triggered when this change is for TIFF_LONG), but at least on Windows, the PyLong_AsLong function returns the equivalent of int32_t. I think PyLong_AsLongLong should return int64_t on all platforms, although I'm not sure if it matters here.

To be clear, using PyLong_AsLong here instead of PyLong_AsLongLong is not a security issue, I'm just not sure whether it could save the wrong values.

[radarhere]

Sure, that seems better than casting the value. I've updated the commit.

[nulano]

PyLong_AsLongLong returns int64_t, not uint64_t. It probably doesn't matter due to how signedness casting works, but it's not the same type. I was just pointing out that PyLong_AsLong has a different output range on Windows vs Linux.

[mgorny]

This change broke Pillow on PowerPC: #8522

To be honest, I don't really understand what's being done here. Given that TIFF_LONG is defined as "32-bit unsigned integer", passing a 64-bit integer (signed or unsigned) seems wrong. I'm guessing on other architectures VA are passed in such a way as to conceal the problem, and it explodes on PowerPC.