diff --git a/lib/zlib/deflate.js b/lib/zlib/deflate.js
index 59e8578..b932d31 100644
--- a/lib/zlib/deflate.js
+++ b/lib/zlib/deflate.js
@@ -632,7 +632,7 @@ const deflate_stored = (s, flush) => {
   }
 
   /* Fill the window with any remaining input. */
-  have = s.window_size - s.strstart - 1;
+  have = s.window_size - s.strstart;
   if (s.strm.avail_in > have && s.block_start >= s.w_size) {
     /* Slide the window down. */
     s.block_start -= s.w_size;