diff --git a/plugins/storage/bin/chown-storage-dir b/plugins/storage/bin/chown-storage-dir
index 4be58586c..3ce7c5c7b 100755
--- a/plugins/storage/bin/chown-storage-dir
+++ b/plugins/storage/bin/chown-storage-dir
@@ -16,13 +16,15 @@ main() {
     exit 1
   fi
 
-  case "$CHOWN_ID" in
-    0 | 1000 | 2000 | 32767 | 165536 | 166536 | 167536 | 198303) ;;
-    *)
-      echo " !     Unsupported chown permissions. Supported values: 0, 1000, 2000, 32767 (and user namespace offset variants)" 1>&2
-      exit 1
-      ;;
-  esac
+  if [[ ! "$CHOWN_ID" =~ ^[0-9]+$ ]]; then
+    echo " !     Unsupported chown permissions. Value must be a non-negative integer." 1>&2
+    exit 1
+  fi
+
+  if ((CHOWN_ID > 65535 && (CHOWN_ID < 165536 || CHOWN_ID > 231071))); then
+    echo " !     Unsupported chown permissions. Supported values: 0-65535 (and user namespace offset variants, 165536-231071)" 1>&2
+    exit 1
+  fi
 
   chown -R "$CHOWN_ID:$CHOWN_ID" "${DOKKU_LIB_ROOT}/data/storage/$DIRECTORY"
 }