Issue #19428: Handle PyMarshal_Read*() errors in run_pyc_file()

Detect also earlier PyMarshal_Read*() errors in zipimport.

Modules/zipimport.c

@@ -939,6 +939,9 @@ read_directory(PyObject *archive)
         header_size = name_size +
            PyMarshal_ReadShortFromFile(fp) +
            PyMarshal_ReadShortFromFile(fp);
+        if (PyErr_Occurred())
+            goto error;
+
         if (fread(dummy, 1, 8, fp) != 8) /* Skip unused fields, avoid fseek */
             goto file_error;
         file_offset = PyMarshal_ReadLongFromFile(fp) + arc_offset;

Python/pythonrun.c

@@ -981,13 +981,17 @@ run_pyc_file(FILE *fp, const char *filename, PyObject *globals,
 
     magic = PyMarshal_ReadLongFromFile(fp);
     if (magic != PyImport_GetMagicNumber()) {
-        PyErr_SetString(PyExc_RuntimeError,
-                   "Bad magic number in .pyc file");
+        if (!PyErr_Occurred())
+            PyErr_SetString(PyExc_RuntimeError,
+                       "Bad magic number in .pyc file");
         return NULL;
     }
     /* Skip mtime and size */
     (void) PyMarshal_ReadLongFromFile(fp);
     (void) PyMarshal_ReadLongFromFile(fp);
+    if (PyErr_Occurred())
+        return NULL;
+
     v = PyMarshal_ReadLastObjectFromFile(fp);
     if (v == NULL || !PyCode_Check(v)) {
         Py_XDECREF(v);