From mboxrd@z Thu Jan  1 00:00:00 1970
From: ebiederm@xmission.com (Eric W. Biederman)
Subject: Re: [PATCH 0/9] proc: protect /proc/<pid>/* files across execve
Date: Mon, 12 Mar 2012 12:13:15 -0700
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To: Djalal Harouni <tixxdz@opendz.org>
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In-Reply-To: <1331421919-15499-1-git-send-email-tixxdz@opendz.org> (Djalal
	Harouni's message of "Sun, 11 Mar 2012 00:25:10 +0100")
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Djalal Harouni <tixxdz@opendz.org> writes:

> Procfs files and other important objects may contain sensitive information
> which must not be seen, inherited or processed across execve.

So I am dense.  /proc/<pid>/mem was special in that it uses a different
set of checks than other files, and to do those access checks
/proc/<pid>/mem needed to look at exec_id.

For all of the access checks that are not written in that silly way.
What is wrong with ptrace_may_access run at every read/write of a file?

We redo all of the permission checks every time so that should avoid
races.

I really think you are trying to solve something that is not broken.
Certainly I could not see your argument for why anything but
/proc/<pid>/mem needs attention.

Eric