fix: for ISO base disk remove premature return after closing sparse diff file so Convert executes.

Ensure diffDisk is converted to the requested format instead of staying sparse.

Signed-off-by: ashwat287 <ashwatpas@gmail.com>

Author: ashwat287

pkg/driverutil/disk.go

@@ -38,23 +38,25 @@ func EnsureDisk(ctx context.Context, instDir, diskSize string, diskImageFormat i
 	if err != nil {
 		return err
 	}
+	destDisk := baseDisk
 	if isBaseDiskISO {
+		destDisk = diffDisk
 		// Create an empty data volume (sparse)
 		diffDiskF, err := os.Create(diffDisk)
 		if err != nil {
 			return err
 		}
 
-		err = diskUtil.MakeSparse(ctx, diffDiskF, 0)
+		err = diskUtil.MakeSparse(ctx, diffDiskF, diskSizeInBytes)
 		if err != nil {
 			diffDiskF.Close()
 			return fmt.Errorf("failed to create sparse diff disk %q: %w", diffDisk, err)
 		}
-		return diffDiskF.Close()
+		diffDiskF.Close()
 	}
 	// Check whether to use ASIF format
 
-	if err = diskUtil.Convert(ctx, diskImageFormat, baseDisk, diffDisk, &diskSizeInBytes, false); err != nil {
+	if err = diskUtil.Convert(ctx, diskImageFormat, destDisk, diffDisk, &diskSizeInBytes, false); err != nil {
 		return fmt.Errorf("failed to convert %q to a disk %q: %w", baseDisk, diffDisk, err)
 	}
 	return err

pkg/imgutil/nativeimgutil/nativeimgutil.go

@@ -62,10 +62,10 @@ func convertTo(destType image.Type, source, dest string, size *int64, allowSourc
 	logrus.Infof("Converting %q (%s) to a %s disk %q", source, srcImg.Type(), destType, dest)
 	switch t := srcImg.Type(); t {
 	case raw.Type:
-		if err = srcF.Close(); err != nil {
-			return err
-		}
 		if destType == raw.Type {
+			if err = srcF.Close(); err != nil {
+				return err
+			}
 			return convertRawToRaw(source, dest, size)
 		}
 	case qcow2.Type: