diff --git a/Lib/test/test_embed.py b/Lib/test/test_embed.py index 70d7367ea9e..6b5d48547b8 100644 --- a/Lib/test/test_embed.py +++ b/Lib/test/test_embed.py @@ -1713,6 +1713,9 @@ def test_audit_run_stdin(self): timeout=support.SHORT_TIMEOUT, returncode=1) + def test_get_incomplete_frame(self): + self.run_embedded_interpreter("test_get_incomplete_frame") + class MiscTests(EmbeddingTestsMixin, unittest.TestCase): def test_unicode_id_init(self): diff --git a/Misc/NEWS.d/next/Core and Builtins/2022-09-21-16-06-37.gh-issue-96975.BmE0XY.rst b/Misc/NEWS.d/next/Core and Builtins/2022-09-21-16-06-37.gh-issue-96975.BmE0XY.rst new file mode 100644 index 00000000000..e6fcb84d7bf --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2022-09-21-16-06-37.gh-issue-96975.BmE0XY.rst @@ -0,0 +1,2 @@ +Fix a crash occurring when :c:func:`PyEval_GetFrame` is called while the +topmost Python frame is in a partially-initialized state. diff --git a/Programs/_testembed.c b/Programs/_testembed.c index a2a2ff40b27..e5b138ce84b 100644 --- a/Programs/_testembed.c +++ b/Programs/_testembed.c @@ -1950,6 +1950,73 @@ static int test_repeated_init_and_inittab(void) return 0; } +static void wrap_allocator(PyMemAllocatorEx *allocator); +static void unwrap_allocator(PyMemAllocatorEx *allocator); + +static void * +malloc_wrapper(void *ctx, size_t size) +{ + PyMemAllocatorEx *allocator = (PyMemAllocatorEx *)ctx; + unwrap_allocator(allocator); + PyEval_GetFrame(); // BOOM! + wrap_allocator(allocator); + return allocator->malloc(allocator->ctx, size); +} + +static void * +calloc_wrapper(void *ctx, size_t nelem, size_t elsize) +{ + PyMemAllocatorEx *allocator = (PyMemAllocatorEx *)ctx; + return allocator->calloc(allocator->ctx, nelem, elsize); +} + +static void * +realloc_wrapper(void *ctx, void *ptr, size_t new_size) +{ + PyMemAllocatorEx *allocator = (PyMemAllocatorEx *)ctx; + return allocator->realloc(allocator->ctx, ptr, new_size); +} + +static void +free_wrapper(void *ctx, void *ptr) +{ + PyMemAllocatorEx *allocator = (PyMemAllocatorEx *)ctx; + allocator->free(allocator->ctx, ptr); +} + +static void +wrap_allocator(PyMemAllocatorEx *allocator) +{ + PyMem_GetAllocator(PYMEM_DOMAIN_OBJ, allocator); + PyMemAllocatorEx wrapper = { + .malloc = &malloc_wrapper, + .calloc = &calloc_wrapper, + .realloc = &realloc_wrapper, + .free = &free_wrapper, + .ctx = allocator, + }; + PyMem_SetAllocator(PYMEM_DOMAIN_OBJ, &wrapper); +} + +static void +unwrap_allocator(PyMemAllocatorEx *allocator) +{ + PyMem_SetAllocator(PYMEM_DOMAIN_OBJ, allocator); +} + +static int +test_get_incomplete_frame(void) +{ + _testembed_Py_Initialize(); + PyMemAllocatorEx allocator; + wrap_allocator(&allocator); + // Force an allocation with an incomplete (generator) frame: + int result = PyRun_SimpleString("(_ for _ in ())"); + unwrap_allocator(&allocator); + Py_Finalize(); + return result; +} + /* ********************************************************* * List of test cases and the function that implements it. @@ -2032,6 +2099,7 @@ static struct TestCase TestCases[] = { #ifndef MS_WINDOWS {"test_frozenmain", test_frozenmain}, #endif + {"test_get_incomplete_frame", test_get_incomplete_frame}, {NULL, NULL} }; diff --git a/Python/ceval.c b/Python/ceval.c index 83c1e1cbeea..94537704417 100644 --- a/Python/ceval.c +++ b/Python/ceval.c @@ -6520,11 +6520,14 @@ _PyEval_GetFrame(void) PyFrameObject * PyEval_GetFrame(void) { - PyThreadState *tstate = _PyThreadState_GET(); - if (tstate->cframe->current_frame == NULL) { + _PyInterpreterFrame *frame = _PyEval_GetFrame(); + while (frame && _PyFrame_IsIncomplete(frame)) { + frame = frame->previous; + } + if (frame == NULL) { return NULL; } - PyFrameObject *f = _PyFrame_GetFrameObject(tstate->cframe->current_frame); + PyFrameObject *f = _PyFrame_GetFrameObject(frame); if (f == NULL) { PyErr_Clear(); }