malloc(): invalid next size (unsorted)

[MohamedAliRashad]

Bug

I get memory allocation crash when i run converter.convert()

Steps to reproduce

from docling.document_converter import DocumentConverter
converter = DocumentConverter()
converter.convert('arabic_book.pdf')

arabic_book.pdf

Docling version

Docling version: 2.39.0
Docling Core version: 2.39.0
Docling IBM Models version: 3.6.0
Docling Parse version: 4.1.0
Python: cpython-313 (3.13.0)
Platform: Linux-6.8.0-63-generic-x86_64-with-glibc2.39

[dosubot]

This crash is almost certainly caused by a bug in a native library used for PDF processing—specifically, pypdfium2 (a wrapper for the PDFium C++ library), which Docling uses for PDF conversion. The error message indicates heap corruption at the C/C++ level, which can be triggered by certain PDF structures or by incompatibilities between pypdfium2/PDFium and newer Python (3.13.0) or glibc (2.39) versions. There are no workarounds or mitigations for this in Docling itself, and the codebase disables thread pools and uses global locks to reduce risk, but cannot prevent these low-level crashes if the underlying library is not fully compatible or has latent bugs (source).

To isolate the problem, try converting a simple, known-good PDF (like a one-page Latin-script document). If only 'arabic_book.pdf' triggers the crash, the issue may be with the file's structure or encoding. If all PDFs crash, it's likely an incompatibility between pypdfium2/PDFium and your Python/glibc environment.

You can also try updating pypdfium2 and its dependencies, or running the conversion with increased logging (-v or -vv on the CLI) and debug visualization flags (like --debug-visualize-cells) to gather more information. If the issue persists, running under a memory debugger (e.g., valgrind) may help pinpoint the source, and you may want to check for or report the issue upstream to pypdfium2/PDFium. If possible, testing with an older Python (e.g., 3.11 or 3.12) or glibc version may avoid the crash (source).

To reply, just mention @dosu.

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