diff --git a/mk-sbuild b/mk-sbuild
index f8d3070..05f8b9a 100755
--- a/mk-sbuild
+++ b/mk-sbuild
@@ -628,15 +628,15 @@ esac
 
 case "$SCHROOT_TYPE" in
     directory|file)
-    if grep -q '\soverlay$' /proc/filesystems \
-            || /sbin/modprobe -q --dry-run overlay; then
-        OVERLAY_FS=overlay
-    if grep -q '\soverlayfs$' /proc/filesystems \
-            || /sbin/modprobe -q --dry-run overlayfs; then
-        OVERLAY_FS=overlayfs
-    else
-        OVERLAY_FS=aufs
-    fi
+        if grep -q '\soverlay$' /proc/filesystems \
+                || /sbin/modprobe -q --dry-run overlay; then
+            OVERLAY_FS=overlay
+        if grep -q '\soverlayfs$' /proc/filesystems \
+                || /sbin/modprobe -q --dry-run overlayfs; then
+            OVERLAY_FS=overlayfs
+        else
+            OVERLAY_FS=aufs
+        fi
 esac
 
 # work around apt's GPG invocation that fails without root's .gnupg directory