diff --git a/chain/file.go b/chain/file.go
index d8a4e58..f29e95e 100644
--- a/chain/file.go
+++ b/chain/file.go
@@ -171,7 +171,7 @@ func cutfile(file string) ([]string, error) {
 			if i+1 != segmentCount {
 				return segment, errors.New("read file err")
 			}
-			copy(buf[num:], make([]byte, pattern.SegmentSize-num))
+			copy(buf[num:], []byte(utils.RandStr(pattern.SegmentSize-num)))
 		}
 
 		hash, err := utils.CalcSHA256(buf)
@@ -228,7 +228,7 @@ func cutFileWithEncryption(file string) ([]string, error) {
 			if i+1 != segmentCount {
 				return segment, errors.New("read file err")
 			}
-			copy(buf[num:], make([]byte, segmentSize-num))
+			copy(buf[num:], []byte(utils.RandStr(segmentSize-num)))
 		}
 
 		hash, err := utils.CalcSHA256(buf)