zrok: WebDAV drive backend follows symlinks outside DriveRoot, enabling host filesystem read/write

zrok is software for sharing web services, files, and network resources. Prior to version 2.0.2, the zrok WebDAV drive backend (davServer.Dir) restricts path traversal through lexical normalization but does not prevent symlink following. When a symbolic link inside the shared DriveRoot points to a location outside that root, remote WebDAV consumers can read files and—on shares without OS-level permission restrictions—write or overwrite files anywhere on the host filesystem accessible to the zrok process. This issue has been patched in version 2.0.2.