Uncaught exception: Overflow in Exiv2::DataBuf::c_data

[joelsgp]

Describe the bug

crashes when opening this particular image, dingus_nowhiskers.png

To Reproduce

Image attached:

you can search dingus the cat or maxwell the cat to find it. hosted here: https://github.com/LeoDog896/maxwell/tree/main/images

Expected behavior

works as usual

Desktop (please complete the following information):

• OS and version: arch linux
• Exiv2 version and source: 0.28.0-1 from arch extra exiv2

Additional context

Add any other information about the problem here.

after I run mogrify -strip from imagemagick, it works like so:

File name       : bibi_nowhiskers.png
File size       : 250179 Bytes
MIME type       : image/png
Image size      : 512 x 512
bibi_nowhiskers.png: No Exif data found in the file

[postscript-dev]

@joelsgp
The exiv2 app is a simple front end to the library and is a good way to demonstrate any problems with an image. If I use the exiv2 app (exiv2-0.28.0-Linux64.tar.gz on Linux Mint 21.1) I can recreate your error.

$ exiv2 --Print xkycvt 245224405-44bb2c8a-37b1-4847-9004-b5950ef47633.png
Uncaught exception: Overflow in Exiv2::DataBuf::c_data

If I repeat the same test using exiv2-0.27.7-Linux64.tar.gz then no error is flagged although also no tags are printed.

ExifTool processes the file without warning/error but the tags displayed are PNG metadata - which Exiv2 does not currently support.

$ exiftool -g 245224405-44bb2c8a-37b1-4847-9004-b5950ef47633.png 
---- ExifTool ----
ExifTool Version Number         : 12.63
---- File ----
File Name                       : 245224405-44bb2c8a-37b1-4847-9004-b5950ef47633.png
Directory                       : .
File Size                       : 253 kB
File Modification Date/Time     : 2023:06:13 15:10:11+01:00
File Access Date/Time           : 2023:06:13 15:10:28+01:00
File Inode Change Date/Time     : 2023:06:13 15:10:28+01:00
File Permissions                : -rw-rw-r--
File Type                       : PNG
File Type Extension             : png
MIME Type                       : image/png
---- PNG ----
Image Width                     : 512
Image Height                    : 512
Bit Depth                       : 8
Color Type                      : RGB with Alpha
Compression                     : Deflate/Inflate
Filter                          : Adaptive
Interlace                       : Noninterlaced
Generated By                    : Generated by the Developer's Image Library (DevIL)
Author                          : 
Description                     : 
---- Composite ----
Image Size                      : 512x512
Megapixels                      : 0.262

Note: Exiv2 can read Exif metadata stored in a PNG file.

It appears that there is a new bug in Exiv2 when processing PNG files. However, I am sorry but I cannot commit more time to investigate your problem.

[kmilos]

The exception comes from here:

exiv2/src/pngchunk_int.cpp

Lines 113 to 114 in 5d1467b

	const byte* text = data.c_data(keysize + 1);
	size_t textsize = data.size() - keysize - 1;

In 0.27.x we used unsafe arithmetic on pData_ ponter directly, but that worked out ok as textsize was 0, which is still valid.

This needs to be fixed for all text chunks, i.e. tEXt, zTXt, and iTXt.

[nicolasfella]

https://bugs.kde.org/show_bug.cgi?id=470852 might be the same issue. The backtrace is

#0  __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44
#1  0x00007ffff3cb08b3 in __pthread_kill_internal (signo=6, threadid=<optimized out>) at pthread_kill.c:78
#2  0x00007ffff3c5fabe in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
#3  0x00007ffff3c4887f in __GI_abort () at abort.c:79
#4  0x00007ffff3ea4cf9 in __gnu_cxx::__verbose_terminate_handler () at ../../../../libstdc++-v3/libsupc++/vterminate.cc:95
#5  0x00007ffff3eb4f6c in __cxxabiv1::__terminate (handler=<optimized out>) at ../../../../libstdc++-v3/libsupc++/eh_terminate.cc:48
#6  0x00007ffff3eb4fd7 in std::terminate () at ../../../../libstdc++-v3/libsupc++/eh_terminate.cc:58
#7  0x00007ffff3eb5238 in __cxxabiv1::__cxa_throw (obj=<optimized out>, tinfo=0x7ffff4044fe8 <typeinfo for std::out_of_range>, dest=0x7ffff3ecb720 <std::out_of_range::~out_of_range()>)
    at ../../../../libstdc++-v3/libsupc++/eh_throw.cc:98
#8  0x00007ffff66cc6a1 in Exiv2::DataBuf::c_data (this=0x7fffffffafd0, offset=7) at /home/nico/workspace/exiv2/src/types.cpp:180
#9  0x00007ffff65d156a in Exiv2::Internal::PngChunk::parseTXTChunk (data=..., keysize=6, type=Exiv2::Internal::PngChunk::tEXt_Chunk) at /home/nico/workspace/exiv2/src/pngchunk_int.cpp:113
#10 0x00007ffff65d0f8c in Exiv2::Internal::PngChunk::decodeTXTChunk (pImage=0xdb15a0, data=..., type=Exiv2::Internal::PngChunk::tEXt_Chunk) at /home/nico/workspace/exiv2/src/pngchunk_int.cpp:54
#11 0x00007ffff6700d30 in Exiv2::PngImage::readMetadata (this=0xdb15a0) at /home/nico/workspace/exiv2/src/pngimage.cpp:435
#12 0x00007ffff7d0146e in Gwenview::Exiv2ImageLoader::load (this=0x7fffffffb2b8, filePath=...) at /home/nico/kde/src/gwenview/lib/exiv2imageloader.cpp:88
#13 0x00007ffff7d5728d in Gwenview::TimeUtils::CacheItem::updateFromExif (this=0x14ac728, url=...) at /home/nico/kde/src/gwenview/lib/timeutils.cpp:87
#14 0x00007ffff7d57120 in Gwenview::TimeUtils::CacheItem::update (this=0x14ac728, fileItem=...) at /home/nico/kde/src/gwenview/lib/timeutils.cpp:74
#15 0x00007ffff7d57024 in Gwenview::TimeUtils::dateTimeForFileItem (fileItem=..., cachePolicy=Gwenview::TimeUtils::UseCache) at /home/nico/kde/src/gwenview/lib/timeutils.cpp:139

[debianmain1]

After updating from 0.27.6-2 to 0.28.0-1 exiv2 & 0.14.0.-3 to 0.14.1-1 libgexiv2 ( Arch via EndeavourOS ), I am running into the same issue. Information here: https://forum.endeavouros.com/t/interesting-shotwell-problem-segfault-from-exiv2-solved/41795 Downgrading returned normal function to Shotwell. I currently have those updates blocked.

[eworm-de]

The fix has been cherry-picked in Arch Linux package exiv2 0.28.0-2.

[joelsgp]

confirmed working fine now, thanks

[debianmain1]

Also confirmed here as working...Thank You!