python
diff --git a/‎Lib/test/test_generators.py
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+19Lines changed: 19 additions & 0 deletions b/‎Lib/test/test_generators.py
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+19Lines changed: 19 additions & 0 deletions
diff --git a/‎Misc/NEWS.d/next/Core and Builtins/2022-10-03-13-35-48.gh-issue-97752.0xTjJY.rst
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+2Lines changed: 2 additions & 0 deletions b/‎Misc/NEWS.d/next/Core and Builtins/2022-10-03-13-35-48.gh-issue-97752.0xTjJY.rst
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diff --git a/‎Python/frame.c
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+3Lines changed: 3 additions & 0 deletions b/‎Python/frame.c
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+3Lines changed: 3 additions & 0 deletions
@@ -206,6 +206,25 @@ def __del__(self):
         finally:
             gc.set_threshold(*thresholds)
 
+    def test_ag_frame_f_back(self):
+        async def f():
+            yield
+        ag = f()
+        self.assertIsNone(ag.ag_frame.f_back)
+
+    def test_cr_frame_f_back(self):
+        async def f():
+            pass
+        cr = f()
+        self.assertIsNone(cr.cr_frame.f_back)
+        cr.close()  # Suppress RuntimeWarning.
+
+    def test_gi_frame_f_back(self):
+        def f():
+            yield
+        gi = f()
+        self.assertIsNone(gi.gi_frame.f_back)
+
 
 
 class ExceptionTest(unittest.TestCase):
 
@@ -0,0 +1,2 @@
+Fix possible data corruption or crashes when accessing the ``f_back`` member
+of newly-created generator or coroutine frames.
@@ -54,6 +54,9 @@ _PyFrame_Copy(_PyInterpreterFrame *src, _PyInterpreterFrame *dest)
     assert(src->stacktop >= src->f_code->co_nlocalsplus);
     Py_ssize_t size = ((char*)&src->localsplus[src->stacktop]) - (char *)src;
     memcpy(dest, src, size);
+    // Don't leave a dangling pointer to the old frame when creating generators
+    // and coroutines:
+    dest->previous = NULL;
 }
Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	+Fix possible data corruption or crashes when accessing the ``f_back`` member
	`2`	`+of newly-created generator or coroutine frames.`
Original file line number	Diff line number	Diff line change
`@@ -54,6 +54,9 @@ _PyFrame_Copy(_PyInterpreterFrame src, _PyInterpreterFrame dest)`
`54`	`54`	`assert(src->stacktop >= src->f_code->co_nlocalsplus);`
`55`	`55`	`Py_ssize_t size = ((char)&src->localsplus[src->stacktop]) - (char )src;`
`56`	`56`	`memcpy(dest, src, size);`
	`57`	`+ // Don't leave a dangling pointer to the old frame when creating generators`
	`58`	`+ // and coroutines:`
	`59`	`+ dest->previous = NULL;`
`57`	`60`	`}`
`58`	`61`
`59`	`62`