Bug#836428: hurd, initscripts: /tmp cleaning deletes files through a firmlink

[Kalle Olavi Niemitalo <kon@iki.fi>]

Richard Braun <rbraun@sceen.net> writes:

> A true fix would mean we provide the same assumptions the init
> scripts on Unix.

Programs deleting or modifying files in /tmp already have to be
careful not to follow other users' symlinks.  Perhaps you could
reuse that somehow.  __hurd_file_name_lookup_retry in glibc has
some code that returns ENOENT if O_NOFOLLOW is used on an
untrusted translator, but I haven't examined whether that
triggers in the /tmp-cleaning case.  (rpctrace doesn't reveal it.
IIRC, it does trigger if I try to cp -a a directory in which a
file uses the hello translator.)