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Date: Thu, 3 Nov 2016 19:24:39 +0100
From: Oleg Nesterov <oleg@redhat.com>
To: Jann Horn <jann@thejh.net>
Cc: security@kernel.org, Alexander Viro <viro@zeniv.linux.org.uk>,
        Paul Moore <paul@paul-moore.com>, Stephen Smalley <sds@tycho.nsa.gov>,
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Subject: Re: [PATCH v3 1/3] fs/exec: don't force writing memory access
Message-ID: <20161103182439.GC11212@redhat.com>
References: <1478142286-18427-1-git-send-email-jann@thejh.net> <1478142286-18427-4-git-send-email-jann@thejh.net>
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On 11/03, Jann Horn wrote:
>
> This shouldn't change behavior in any way - at this point, there should be
> no non-writable mappings, only the initial stack mapping -,

So this FOLL_FORCE just adds the unnecessary confusion,

> but this change
> makes it easier to reason about the correctness of the following commits
> that place restrictions on forced memory writes.

and to me it looks like a good cleanup regardless. Exactly because it
is not clear why do we need FOLL_FORCE.

> Signed-off-by: Jann Horn <jann@thejh.net>
> Reviewed-by: Janis Danisevskis <jdanis@android.com>

Acked-by: Oleg Nesterov <oleg@redhat.com>