On Tue, May 28, 2024 at 03:28:18PM +0200, Miklos Szeredi wrote: > > open_by_handle_at looks up the superblock based on that identifier. > > The open file needs a specific mount, holding the superblock is not > sufficient. A strut file needs a vfsmount, yes. And it better be reachable by the calling process. And maybe an optional restriction to a specific mount by the caller might be useful, but I can't see how it is required.