From 04c479cc1a3d91f71afcf2b65d605a674fc96ee9 Mon Sep 17 00:00:00 2001 From: Serhiy Storchaka Date: Sat, 23 Sep 2023 09:39:24 +0300 Subject: [PATCH] gh-109521: Fix obscure cases handling in PyImport_GetImporter() (GH-109522) PyImport_GetImporter() now sets RuntimeError if it fails to get sys.path_hooks or sys.path_importer_cache or they are not list and dict correspondingly. Previously it could return NULL without setting error in obscure cases, crash or raise SystemError if these attributes have wrong type. (cherry picked from commit 62c7015e89cbdedb5218d4fedd45f971885f67a8) Co-authored-by: Serhiy Storchaka --- ...-09-17-21-47-31.gh-issue-109521.JDF6i9.rst | 5 ++++ Python/import.c | 26 +++++++++++++++---- 2 files changed, 26 insertions(+), 5 deletions(-) create mode 100644 Misc/NEWS.d/next/C API/2023-09-17-21-47-31.gh-issue-109521.JDF6i9.rst diff --git a/Misc/NEWS.d/next/C API/2023-09-17-21-47-31.gh-issue-109521.JDF6i9.rst b/Misc/NEWS.d/next/C API/2023-09-17-21-47-31.gh-issue-109521.JDF6i9.rst new file mode 100644 index 00000000000000..338650c9246686 --- /dev/null +++ b/Misc/NEWS.d/next/C API/2023-09-17-21-47-31.gh-issue-109521.JDF6i9.rst @@ -0,0 +1,5 @@ +:c:func:`PyImport_GetImporter` now sets RuntimeError if it fails to get +:data:`sys.path_hooks` or :data:`sys.path_importer_cache` or they are not +list and dict correspondingly. Previously it could return NULL without +setting error in obscure cases, crash or raise SystemError if these +attributes have wrong type. diff --git a/Python/import.c b/Python/import.c index 3f3f2a2b681351..54232a130082f0 100644 --- a/Python/import.c +++ b/Python/import.c @@ -2380,9 +2380,14 @@ get_path_importer(PyThreadState *tstate, PyObject *path_importer_cache, PyObject *importer; Py_ssize_t j, nhooks; - /* These conditions are the caller's responsibility: */ - assert(PyList_Check(path_hooks)); - assert(PyDict_Check(path_importer_cache)); + if (!PyList_Check(path_hooks)) { + PyErr_SetString(PyExc_RuntimeError, "sys.path_hooks is not a list"); + return NULL; + } + if (!PyDict_Check(path_importer_cache)) { + PyErr_SetString(PyExc_RuntimeError, "sys.path_importer_cache is not a dict"); + return NULL; + } nhooks = PyList_Size(path_hooks); if (nhooks < 0) @@ -2425,11 +2430,22 @@ PyImport_GetImporter(PyObject *path) { PyThreadState *tstate = _PyThreadState_GET(); PyObject *path_importer_cache = PySys_GetObject("path_importer_cache"); + if (path_importer_cache == NULL) { + PyErr_SetString(PyExc_RuntimeError, "lost sys.path_importer_cache"); + return NULL; + } + Py_INCREF(path_importer_cache); PyObject *path_hooks = PySys_GetObject("path_hooks"); - if (path_importer_cache == NULL || path_hooks == NULL) { + if (path_hooks == NULL) { + PyErr_SetString(PyExc_RuntimeError, "lost sys.path_hooks"); + Py_DECREF(path_importer_cache); return NULL; } - return get_path_importer(tstate, path_importer_cache, path_hooks, path); + Py_INCREF(path_hooks); + PyObject *importer = get_path_importer(tstate, path_importer_cache, path_hooks, path); + Py_DECREF(path_hooks); + Py_DECREF(path_importer_cache); + return importer; }