diff --git a/shamir/shamir.go b/shamir/shamir.go
index fde60bfd1f85..d664e90a149c 100644
--- a/shamir/shamir.go
+++ b/shamir/shamir.go
@@ -168,7 +168,7 @@ func Split(secret []byte, parts, threshold int) ([][]byte, error) {
 	}
 
 	// Generate random list of x coordinates
-	xCoordinates := mathrand.Perm(255)
+	xCoordinates := mathrand.Perm(parts)
 
 	// Allocate the output array, initialize the final byte
 	// of the output with the offset. The representation of each