diff --git a/lib/nodejs/lib/thrift/transport.js b/lib/nodejs/lib/thrift/transport.js
index a926a6d..06351a4 100644
--- a/lib/nodejs/lib/thrift/transport.js
+++ b/lib/nodejs/lib/thrift/transport.js
@@ -165,7 +165,7 @@
     var bufSize = (unreadedSize * 2 > this.defaultReadBufferSize) ? unreadedSize * 2 : this.defaultReadBufferSize;
     var buf = new Buffer(bufSize);
     if (unreadedSize > 0) {
-      this.inBuf.copy(buf, 0, this.readCursor, unreadedSize);
+      this.inBuf.copy(buf, 0, this.readCursor, this.writeCursor);
     }
     this.readCursor = 0;
     this.writeCursor = unreadedSize;
@@ -195,7 +195,7 @@
       throw new InputBufferUnderrunError();
     }
     var buf = new Buffer(this.writeCursor - this.readCursor);
-    this.inBuf.copy(buf, 0, this.readCursor, this.writeCursor - this.readCursor);
+    this.inBuf.copy(buf, 0, this.readCursor, this.writeCursor);
     this.readCursor = this.writeCursor;
     return buf;
   },