Re: `du` check for directory loop avoidance

[Terry Bowling]

Bump

Does anyone have any thoughts or guidance on how we might proceed with this?

On 01/12/2014 07:37 PM, Terry Bowling wrote:
> Hello all,
>
> After discussing further in RH BZ 1045086 
> (http://rhn.redhat.com/errata/RHSA-2013-1652.htmlincludes), we I would 
> like to discuss the following options with upstream for consistency.
>
> 1.  Ensure the new warning for du is upstream:  "mount point %s 
> already traversed"
>
> 2. Ensure the other commands are using the same message for 
> consistency (chcon, chmod, chown-core, remove)
>
> 3. Evaluate if a separate exit code for this condition is 
> appropriate.  This would allow for slightly easier scripting to check 
> for this condition and rule out any concerns that the warning message 
> might change in the future.
>
> 4. Evaluate find, ls  - does it make sense for these to be consistent 
> as well?
>
> After discussing here, I will likely submit a BZ for #2 in against 
> RHEL.  And if all agree, I can submit a BZ for #3 and/or #4 as well.
>
> Thanks to all in advance for discussing this and helping us work this 
> out.  I know it's a tedious topic.  I will also document this behavior 
> for RHEL & Fedora to provide a final document to direct all future 
> inquiries so that we can quit discussing it in the future!
> -Terry
>
> On 12/19/2013 04:37 AM, Bernhard Voelker wrote:
> > On 12/18/2013 07:41 PM, Pádraig Brady wrote:
> > > I need to look into this some more,
> > > but we should at least reword the warning to something more generic
> > BTW: the diagnostic in du(1) has been improved in 8.20 by commit
> >
> >    http://git.sv.gnu.org/cgit/coreutils.git/commit/?id=cf7e1b5b
> >
> > but chcon, chmod, chown, chgrp, rm, and mv are affected, too:
> >
> >    $ git grep emit_cycle_warning | cat
> >    src/chcon.c:          emit_cycle_warning (file_full_name);
> >    src/chmod.c:          emit_cycle_warning (file_full_name);
> >    src/chown-core.c:          emit_cycle_warning (file_full_name);
> >    src/du.c:                emit_cycle_warning (file);
> >    src/remove.c:      emit_cycle_warning (ent->fts_path);
> >    src/system.h:#define emit_cycle_warning(file_name)    \
> >
> > e.g.
> >
> >    $ mount -t tmpfs tmpfs /mnt
> >
> >    $ mkdir /mnt/mnt
> >
> >    $ mount --bind /mnt /mnt/mnt
> >
> >    $ du /mnt
> >    du: mount point ‘/mnt/mnt’ already traversed
> >    0    /mnt
> >
> >    $ chown -R root  /mnt
> >    chown: WARNING: Circular directory structure.
> >    This almost certainly means that you have a corrupted file system.
> >    NOTIFY YOUR SYSTEM MANAGER.
> >    The following directory is part of the cycle:
> >      ‘/mnt/mnt’
> >
> > Just for the record, non-FTS ls(1) uses a different diagnostic:
> >
> >    $ ls -R /mnt
> >    /mnt:
> >    mnt
> >    ls: /mnt/mnt: not listing already-listed directory
> >
> > It seems that there is still room for improvement.
> >
> > Have a nice day,
> > Berny