[PATCH] Fix readdir_r with long file names

[Rich Felker]

On Fri, Jun 07, 2013 at 09:55:47AM +0200, Florian Weimer wrote:
> On 06/07/2013 03:30 AM, Rich Felker wrote:
> >On Thu, Jun 06, 2013 at 03:53:16PM -0400, KOSAKI Motohiro wrote:
> >>I mean, portable applications should use readdir_r correctly and Linux specific
> >>one should use readdir instead.
> >>
> >>Side note: the above man page is not a theoretical issue. At least, Solaris
> >>requires it.
> >>
> >>Am I missing something?
> >
> >Yes, the fact that the Austin Group is planning to require readdir to
> >be thread-safe and to mark readdir_r obsolescent.
> 
> This is good news.

Very good news. I've wanted this change ever since I first learned
about readdir_r, and I'm very glad this NAME_MAX issue has provided
the push to get it done.

> > So effort put into
> >making readdir_r more usable, or worse yet, adding a readdir4, is a
> >waste of effort. Just make sure readdir_r is _safe_ against buffer
> >overflows from buggy FUSE modules, and advise application developers
> >to use readdir, not readdir_r.
> 
> Does this mean that you agree with the basic approach of the patch?

Yes. I just disagree with recommending that portable applications use
readdir_r (as discussed on the Austin Group tracker/list, it has major
problems related to NAME_MAX not being mandatory) and with the idea
(by someone else, not you) to add a readdir4 rather than just
deprecating caller-provided buffers for reading directories. Those
were the only things I was commenting on.

Rich