How to: filesystem guards
avoid traversing into other filesystems  using `--xdev` / volflag `:c,xdev`, skipping any symlinks or bind-mounts to another HDD for example

and/or you can `--xvol` / `:c,xvol` to ignore all symlinks leaving the volume's top directory, but still allow bind-mounts pointing elsewhere

* symlinks are permitted with `xvol` if they point into another volume where the user has the same level of access

these options will reduce performance; unlikely worst-case estimates are 14% reduction for directory listings, 35% for download-as-tar

as of copyparty v1.7.0 these options also prevent file access at runtime -- in previous versions it was just hints for the indexer