gh-122071: Fixed traceback leaks global code when file does not exist

Lib/linecache.py

@@ -182,6 +182,10 @@ def lazycache(filename, module_globals):
         loader = getattr(spec, 'loader', None)
         if loader is None:
             loader = module_globals.get('__loader__')
+        mod_file = module_globals.get('__file__')
+        import importlib._bootstrap_external
+        if isinstance(loader, importlib._bootstrap_external.SourceFileLoader) and (not mod_file or (not mod_file.endswith(filename) and not mod_file.endswith('.pyc'))):
+            return False
         get_source = getattr(loader, 'get_source', None)
 
         if name and get_source:

Lib/test/test_linecache.py

@@ -206,8 +206,8 @@ def test_lazycache_smoke(self):
         lines = linecache.getlines(NONEXISTENT_FILENAME, globals())
         linecache.clearcache()
         self.assertEqual(
-            True, linecache.lazycache(NONEXISTENT_FILENAME, globals()))
-        self.assertEqual(1, len(linecache.cache[NONEXISTENT_FILENAME]))
+            False, linecache.lazycache(NONEXISTENT_FILENAME, globals()))
+        self.assertEqual(False, NONEXISTENT_FILENAME in linecache.cache)
         # Note here that we're looking up a nonexistent filename with no
         # globals: this would error if the lazy value wasn't resolved.
         self.assertEqual(lines, linecache.getlines(NONEXISTENT_FILENAME))
@@ -232,11 +232,11 @@ def test_lazycache_bad_filename(self):
 
     def test_lazycache_already_cached(self):
         linecache.clearcache()
-        lines = linecache.getlines(NONEXISTENT_FILENAME, globals())
+        lines = linecache.getlines(FILENAME, globals())
         self.assertEqual(
             False,
-            linecache.lazycache(NONEXISTENT_FILENAME, globals()))
-        self.assertEqual(4, len(linecache.cache[NONEXISTENT_FILENAME]))
+            linecache.lazycache(FILENAME, globals()))
+        self.assertEqual(4, len(linecache.cache[FILENAME]))
 
     def test_memoryerror(self):
         lines = linecache.getlines(FILENAME)

Misc/NEWS.d/next/Core and Builtins/2024-07-22-13-58-16.gh-issue-122071.c5EQZL.rst

@@ -0,0 +1 @@
+Fix global code leaks when reporting tracebacks in the REPL and :func:`exec`.