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Date: Tue, 28 Nov 2000 11:06:02 -0500 (EST)
From: Alexander Viro <viro@math.psu.edu>
To: Tigran Aivazian <tigran@veritas.com>
cc: "David S. Miller" <davem@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: bug in count_open_files() or a strange granularity?
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On Tue, 28 Nov 2000, Tigran Aivazian wrote:

>        /* switch the open fds from old_user to new_user */
>         read_lock(&files->file_lock);
>         nr_open = close_files(files, 0); /* 0 means don't close them */
>         atomic_sub(nr_open, &old_user->files);
>         atomic_add(nr_open, &new_user->files);
>         read_unlock(&files->file_lock);

That makes no sense - how do you count the descriptors in shared ->files?
And how on the Earth do you count SCM_RIGHTS packets? Because they make
a great way to fool any use of that stuff for resource-limit type of
applications (stash the descriptors into SCM_RIGHTS cookie, send them to
yourself and close them).

Basically, I don't see what are you counting.

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