Skip to content

Fix PyArg_ParseTuple format mismatch and non-NULL return with exception in stream module #331

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
devdanzin wants to merge 2 commits into
base: master
Choose a base branch
from
Open

Fix PyArg_ParseTuple format mismatch and non-NULL return with exception in stream module #331

Changes from 1 commit
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
5867f19
fix: release buffers and free memory on error paths
devdanzin Apr 1, 2026
0957fe1
fix: correct PyArg_ParseTuple format and non-NULL return with excepti…
devdanzin Apr 1, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
Prev Previous commit
fix: correct PyArg_ParseTuple format and non-NULL return with excepti… 
…on in stream module

- Fix _compress_bound: format "OI" expects (PyObject*, unsigned int) but only
  &input_size is provided. The "O" writes a PyObject* into a uint32_t —
  type mismatch and memory corruption on every call. Change to "I" to match
  the identical _input_bound function at line 1091.

- Fix _compress: when update_context_after_process fails, PyErr_Format sets
  an exception but goto exit_now returns the already-created py_dest (non-NULL).
  This violates the Python/C API contract (returning a result with an exception
  set), causing SystemError. Clear py_dest before the goto.

Found using cext-review-toolkit (https://github.com/devdanzin/cext-review-toolkit).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
  • Loading branch information
@devdanzin @claude
devdanzin and claude committed Apr 1, 2026
commit 0957fe173e3ca994d6388707068a4f7410ada910
3 changes: 2 additions & 1 deletion lz4/stream/_stream.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1063,7 +1063,7 @@ _compress_bound (PyObject * Py_UNUSED (self), PyObject * args)
/* Positional arguments: input_size
* Keyword arguments : none
*/
if (!PyArg_ParseTuple (args, "OI", &input_size))
if (!PyArg_ParseTuple (args, "I", &input_size))
{
goto exit_now;
}
Expand Down Expand Up @@ -1211,6 +1211,7 @@ _compress (PyObject * Py_UNUSED (self), PyObject * args)

if (context->strategy.ops->update_context_after_process (context) != 0)
{
Py_CLEAR (py_dest);
PyErr_Format (PyExc_RuntimeError, "Internal error");
goto exit_now;
}
Expand Down
Loading