Messages in this thread | | | From | Andy Lutomirski <> | Date | Fri, 28 Aug 2015 18:04:30 -0700 | Subject | Re: [RFC v6 03/40] vfs: Add MAY_DELETE_SELF and MAY_DELETE_CHILD permission flags |
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On Aug 28, 2015 2:54 PM, "Andreas Grünbacher" <andreas.gruenbacher@gmail.com> wrote: > > 2015-08-28 23:36 GMT+02:00 Andy Lutomirski <luto@amacapital.net>: > > Silly question from the peanut gallery: is there any such thing as > > opening an fd pointing at a file such that the "open file description" > > (i.e. the struct file) captures the right to delete the file? > > > > IOW do we need FMODE_DELETE_SELF? > > When would that permission be checked, what syscall would you use to > unlink an open file descriptor?
Good point. It's remotely plausible that there's some trick with bind mounts, it's likely possible to unlink a directory by fd (using unlinkat), and you can *link* a file (with linkat or /proc), but unlinkat doesn't appear to allow you to unlink a file by fd.
--Andy
> > Thanks, > Andreas
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