diff --git a/Misc/NEWS.d/next/Core and Builtins/2023-07-18-16-13-51.gh-issue-106092.bObgRM.rst b/Misc/NEWS.d/next/Core and Builtins/2023-07-18-16-13-51.gh-issue-106092.bObgRM.rst
new file mode 100644
index 00000000000000..7fb5b45c763e45
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2023-07-18-16-13-51.gh-issue-106092.bObgRM.rst
@@ -0,0 +1,2 @@
+Fix a segmentation fault caused by a use-after-free bug in ``frame_dealloc``
+when the trashcan delays the deallocation of a ``PyFrameObject``.
diff --git a/Objects/frameobject.c b/Objects/frameobject.c
index 18820551a0547e..ca31ca14e96678 100644
--- a/Objects/frameobject.c
+++ b/Objects/frameobject.c
@@ -879,9 +879,6 @@ frame_dealloc(PyFrameObject *f)
/* It is the responsibility of the owning generator/coroutine
* to have cleared the generator pointer */
- assert(f->f_frame->owner != FRAME_OWNED_BY_GENERATOR ||
- _PyFrame_GetGenerator(f->f_frame)->gi_frame_state == FRAME_CLEARED);
-
if (_PyObject_GC_IS_TRACKED(f)) {
_PyObject_GC_UNTRACK(f);
}
@@ -889,10 +886,14 @@ frame_dealloc(PyFrameObject *f)
Py_TRASHCAN_BEGIN(f, frame_dealloc);
PyObject *co = NULL;
+ /* GH-106092: If f->f_frame was on the stack and we reached the maximum
+ * nesting depth for deallocations, the trashcan may have delayed this
+ * deallocation until after f->f_frame is freed. Avoid dereferencing
+ * f->f_frame unless we know it still points to valid memory. */
+ _PyInterpreterFrame *frame = (_PyInterpreterFrame *)f->_f_frame_data;
+
/* Kill all local variables including specials, if we own them */
- if (f->f_frame->owner == FRAME_OWNED_BY_FRAME_OBJECT) {
- assert(f->f_frame == (_PyInterpreterFrame *)f->_f_frame_data);
- _PyInterpreterFrame *frame = (_PyInterpreterFrame *)f->_f_frame_data;
+ if (f->f_frame == frame && frame->owner == FRAME_OWNED_BY_FRAME_OBJECT) {
/* Don't clear code object until the end */
co = frame->f_executable;
frame->f_executable = NULL;
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