Detailed steps to reproduce the problem?

In bsonjs/bsonjs.c's dumps(), json_len is declared size_t (matching libbson's bson_as*_extended_json output-length parameters) but is passed to Py_BuildValue("s#", json, json_len). bsonjs.h defines PY_SSIZE_T_CLEAN before including Python.h, so the "s#" format code reads a Py_ssize_t out of the varargs list, not a size_t. This happens to work on today's common 64-bit platforms where the two types are the same width, but is reading the wrong type out of the varargs list. load()/loads() on the read side already use Py_ssize_t correctly.

Definition of done: what must be done to consider the task complete?

Cast json_len to Py_ssize_t at the Py_BuildValue call site. Fix already up: mongodb-labs/python-bsonjs#114.

The exact Python version used, with patch level:

N/A — latent on any platform where size_t and Py_ssize_t differ in width; harmless today on common 64-bit platforms.

The exact version of PyMongo used, with patch level:

N/A — not a PyMongo dependency; found via code review.

Describe how MongoDB is set up. Local vs Hosted, version, topology, load balanced, etc.

N/A

The operating system and version (e.g. Windows 7, OSX 10.8, ...)

N/A

Web framework or asynchronous network library used, if any, with version (e.g. Django 1.7, mod_wsgi 4.3.0, gevent 1.0.1, Tornado 4.0.2, ...)

N/A

Security Vulnerabilities

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