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Date:   Thu, 13 Dec 2018 10:40:32 +1100 (AEDT)
From:   James Morris <jmorris@namei.org>
To:     Florian Weimer <fweimer@redhat.com>
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Subject: Re: [RFC PATCH v1 0/5] Add support for O_MAYEXEC
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On Wed, 12 Dec 2018, Florian Weimer wrote:

> * James Morris:
> 
> > If you're depending on the script interpreter to flag that the user may 
> > execute code, this seems to be equivalent in security terms to depending 
> > on the user.  e.g. what if the user uses ptrace and clears O_MAYEXEC?
> 
> The argument I've heard is this: Using ptrace (and adding the +x
> attribute) are auditable events.

I guess you could also preload a modified libc which strips the flag.


-- 
James Morris
<jmorris@namei.org>