diff --git a/Modules/zipimport.c b/Modules/zipimport.c
index 06abb31..914bf5d 100644
--- a/Modules/zipimport.c
+++ b/Modules/zipimport.c
@@ -1112,6 +1112,11 @@ get_data(PyObject *archive, PyObject *toc_entry)
     }
     file_offset += l;           /* Start of file data */
 
+    if (data_size > LONG_MAX - 1) {
+        fclose(fp);
+        PyErr_NoMemory();
+        return NULL;
+    }
     bytes_size = compress == 0 ? data_size : data_size + 1;
     if (bytes_size == 0)
         bytes_size++;