bpo-40826: Update PyOS_InterruptOccurred to handle tstate is NULL

Author: corona10

Lib/test/test_repl.py

@@ -93,6 +93,21 @@ def test_multiline_string_parsing(self):
         output = kill_python(p)
         self.assertEqual(p.returncode, 0)
 
+    @cpython_only
+    @unittest.skipIf(sys.platform =="win32", '')
+    def test_close_fd_zero(self):
+        user_input = '''\
+        import os
+        os.close(0)
+        '''
+        user_input = dedent(user_input)
+        user_input = user_input.encode()
+        p = spawn_repl()
+        with SuppressCrashReport():
+            p.stdin.write(user_input)
+        output = kill_python(p)
+        self.assertEqual(p.returncode, 0)
+
 
 if __name__ == "__main__":
     unittest.main()

Misc/NEWS.d/next/Core and Builtins/2020-05-31-13-57-36.bpo-40826.TKBXAB.rst

@@ -0,0 +1,2 @@
+Fix segfaults issue when close file descriptor 0 on REPL. Patch by Dong-hee
+Na.

Modules/signalmodule.c

@@ -1782,8 +1782,12 @@ PyOS_FiniInterrupts(void)
 int
 PyOS_InterruptOccurred(void)
 {
-    PyInterpreterState *interp = _PyInterpreterState_GET();
-    if (!_Py_ThreadCanHandleSignals(interp)) {
+    PyThreadState *tstate = _PyThreadState_GET();
+    if (tstate == NULL) {
+        // FIXME: PyGILState_GetThisThreadState doesn't support subinterpreters.
+        tstate = PyGILState_GetThisThreadState();
+    }
+    if (!_Py_ThreadCanHandleSignals(tstate->interp)) {
         return 0;
     }