--- a/ntfsprogs/ntfsclone.c	2018-05-16 18:46:47.114964000 +0200
+++ b/ntfsprogs/ntfsclone.c	2018-07-16 14:03:20.273809100 +0200
@@ -776,6 +776,10 @@ 
 
 		/* possible partial cluster holding the backup boot sector */
 	backup_bootsector = (lcn + 1)*csize >= full_device_size;
+	buff = (char*)ntfs_malloc(csize);
+	if (!buff)
+		err_exit("Not enough memory");
+
 	if (backup_bootsector) {
 		csize = full_device_size - lcn*csize;
 		if (csize < 0) {
@@ -783,10 +787,6 @@ 
 		}
 	}
 
-	buff = (char*)ntfs_malloc(csize);
-	if (!buff)
-		err_exit("Not enough memory");
-
 // need reading when not about to write ?
 	if (read_all(fd, buff, csize) == -1) {
 
@@ -1507,6 +1507,7 @@ 
 	s64 mft_no;
 	u32 mft_record_size;
 	u32 csize;
+	u32 buff_size;
 	u32 bytes_per_sector;
 	u32 records_per_set;
 	u32 clusters_per_set;
@@ -1524,15 +1525,18 @@ 
 		/*
 		 * Depending on the sizes, there may be several records
 		 * per cluster, or several clusters per record.
+		 * Anyway, full clusters are needed for rescuing bad ones.
 		 */
 	if (csize >= mft_record_size) {
 		records_per_set = csize/mft_record_size;
 		clusters_per_set = 1;
+		buff_size = csize;
 	} else {
 		clusters_per_set = mft_record_size/csize;
 		records_per_set = 1;
+		buff_size = mft_record_size;
 	}
-	buff = (char*)ntfs_malloc(mft_record_size);
+	buff = (char*)ntfs_malloc(buff_size);
 	if (!buff)
 		err_exit("Not enough memory");
 
@@ -1585,6 +1589,7 @@ 
 	void *fd;
 	u32 indx_record_size;
 	u32 csize;
+	u32 buff_size;
 	u32 bytes_per_sector;
 	u32 records_per_set;
 	u32 clusters_per_set;
@@ -1601,16 +1606,19 @@ 
 		/*
 		 * Depending on the sizes, there may be several records
 		 * per cluster, or several clusters per record.
+		 * Anyway, full clusters are needed for rescuing bad ones.
 		 */
 	indx_record_size = image->ni->vol->indx_record_size;
 	if (csize >= indx_record_size) {
 		records_per_set = csize/indx_record_size;
 		clusters_per_set = 1;
+		buff_size = csize;
 	} else {
 		clusters_per_set = indx_record_size/csize;
 		records_per_set = 1;
+		buff_size = indx_record_size;
 	}
-	buff = (char*)ntfs_malloc(indx_record_size);
+	buff = (char*)ntfs_malloc(buff_size);
 	if (!buff)
 		err_exit("Not enough memory");