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Message-ID: <804dabb00812031527k3fae11dcnef3b1696c3d136f8@mail.gmail.com>
Date: Thu, 4 Dec 2008 07:27:39 +0800
From: "Peter Teoh" <htmldeveloper@gmail.com>
To: "Geoffrey McRae" <geoff@rabidhost.com>
Subject: Re: New Security Features, Please Comment
Cc: "Alan Cox" <alan@lxorguk.ukuu.org.uk>,
       "Nick Andrew" <nick@nick-andrew.net>, linux-kernel@vger.kernel.org
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On Thu, Dec 4, 2008 at 7:08 AM, Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
>> The children are pre-forked, so the overhead is in the setup... then
>> when the app recieves a request, it sets the child's uid to the uid of
>> the website, and then passes the request to the child, which, now, the
>> child is running as the website owner.
>
> But the child process may already have been trojanned by a previous user
> so it gains you nothing.
>

Yes, I thought so too.   The trojanized child, even though most of the
time unprivileged, can wait for that window of opportunity when its
privilege is escalated, by polling, and when it received the
privilege, immediate jump into action.

Thanks.

-- 
Regards,
Peter Teoh

Ernest Hemingway - "Never mistake motion for action."
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