Re: ZFS to support chflags?

On Thu, Apr 12, 2007 at 01:28:11PM -0400, Kris Kennaway wrote:
> On Thu, Apr 12, 2007 at 11:42:37AM +0100, Robert Watson wrote:
> > 
> > On Thu, 12 Apr 2007, Bernd Walter wrote:
> > 
> > >On Wed, Apr 11, 2007 at 08:04:03PM -0400, John Nielsen wrote:
> > >
> > >>I just moved /usr over to a zpool on my -CURRENT system. Performance and 
> > >>stability are both excellent so far. (Thanks Pawel!) However I noticed 
> > >>that setting FS flags on files with chflags is not supported. Would it be 
> > >>feasible to add support for flags on ZFS, and if so are there plans to do 
> > >>so?
> > >>
> > >>If not (and/or in the meantime), are there any places in the base system 
> > >>where flags are required for normal operation? (/var maybe?)
> > >
> > >Some binaries have such flags set, but it is not required, otherwise 
> > >diskless NFS wouldn't work. I often see installworld warnings about beeing 
> > >unable to set extended flags on ld.so and others on my diskless boxes.
> > 
> > I'm not a big fan of setting these flags -- I fairly frequently run into 
> > problems when I installworld an NFS root on the NFS host, then try to work 
> > with it over NFS from the NFS-booted system, as the flags can't be removed 
> > via NFS.  They don't offer a security benefit as-installed, and perhaps 
> > offer a benefit with respect to preventing people from shooting themselves 
> > in the foot (or perhaps not).
> 
> Yeah, historical intentions notwithstanding, the real benefit of schg
> flags on critical pieces is anti foot-shooting.  e.g. you really don't
> want to accidentally delete ld-elf.so.1 or libc.so.7 or init.
> You can usually recover from this, but it can mess up your whole day
> :)

The idea is obvious, but it's not up to date to be really usefull beside
a few special cases.
E.g. I don't mind loosing ld-elf.so.1 if mount* and restore are lost as
well.
On the other hand we have /rescue today - schg would make way more sense
there, but it's currently unprotected.

-- 
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