Re: recent nfs change causes autofs regression

Frank van Maarseveen
2007-08-31T08:29:13Z

On Fri, Aug 31, 2007 at 09:40:28AM +0200, Jakob Oestergaard wrote:
> On Thu, Aug 30, 2007 at 10:16:37PM -0700, Linus Torvalds wrote:
> >
> ...
> > > Why aren't we doing that for any other filesystem than NFS?
> >
> > How hard is it to acknowledge the following little word:
> >
> > "regression"
> >
> > It's simple. You broke things. You may want to fix them, but you need to
> > fix them in a way that does not break user space.
>
> Trond has a point Linus.
>
> What he "broke" is, for example, a ro mount being mounted as rw.
>
> That *could* be a very serious security (etc.etc.) problem which he just fixed.
> Anything depending on read-only not being enforced will cease to work, of
> course, and that is what a few people complain about(!).
>
> If ext3 in some rare case (which would still mean it hit a few thousand users)
> failed to remember that a file had been marked read-only and allowed writes to
> it, wouldn't we want to fix that too? It would cause regressions, but we'd fix
> it, right?
>
> mount passes back the error code on a failed mount. autofs passes that error
> along too (when people configure syslog correctly). In short; when these
> serious mistakes are made and caught, the admin sees an error in his logs.

Hua explained already that seeing the error is not the same as fixing
the error: he cannot fix it because NFS implies other systems we _must_
co-operate with.

--
Frank