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Date: Thu, 29 Sep 2016 18:09:01 +0200
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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        Janis Danisevskis <jdanis@google.com>,
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        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/3] fs/exec: don't force writing memory access
Message-ID: <20160929160901.GB30031@redhat.com>
References: <1475103281-7989-1-git-send-email-jann@thejh.net> <1475103281-7989-2-git-send-email-jann@thejh.net>
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On 09/29, Jann Horn wrote:
>
> @@ -204,7 +204,7 @@ static struct page *get_arg_page(struct linux_binprm *bprm, unsigned long pos,
>  	 * doing the exec and bprm->mm is the new process's mm.
>  	 */
>  	ret = get_user_pages_remote(current, bprm->mm, pos, 1, write,
> -			1, &page, NULL);
> +			0, &page, NULL);

To me this looks like a reasonable cleanup regardless, FOLL_FORCE
just adds the unnecessary confusion here.

Oleg.