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Date: Thu, 7 Dec 2000 18:45:17 +0200 (MET DST)
From: Szabolcs Szakacsits <szaka@f-secure.com>
To: Tigran Aivazian <tigran@veritas.com>
cc: <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] Broken NR_RESERVED_FILES
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On Thu, 7 Dec 2000, Tigran Aivazian wrote:

> On Thu, 7 Dec 2000, Szabolcs Szakacsits wrote:
> > Read the whole get_empty_filp function, especially this part, note the
> > goto new_one below and the part you didn't include above [from
> > the new_one label],
> >
> >         if (files_stat.nr_files < files_stat.max_files) {
> >                 file_list_unlock();
> >                 f = kmem_cache_alloc(filp_cachep, SLAB_KERNEL);
> >                 file_list_lock();
> >                 if (f) {
> >                         files_stat.nr_files++;
> >                         goto new_one;
> >                 }
>
> I have read the whole function, including the above code, of course. The
> new_one label has nothing to do with freelists -- it adds the file to the
> anon_list, where the new arrivales from the slab cache go. The goto
> new_one above is there simply to initialize the structure with sane
> initial values

OK, 2.2 has

                put_inuse(f);

instead of putting it to anon_list, so 2.4 seems ok.

	Szaka

> So, the normal user _cannot_ take a file structure from the freelist
> unless it contains more than NR_RESERVED_FILE entries. Please read the
> whole function and see it for yourself.
>
> Regards,
> Tigran
>
>

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