From mboxrd@z Thu Jan  1 00:00:00 1970
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To: 9fans@cse.psu.edu
Subject: Re: [9fans] 4th edition file server available
From: "rob pike, esq." <rob@mightycheese.com>
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Date: Mon, 13 Jan 2003 09:19:37 -0800
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A less drastic step would be to disable network ports such as
cpu and telnet, to require people to use the console to debug.

-rob

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Message-ID: <14897aa3a24d632f340f30863deb7850@hamnavoe.demon.co.uk>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] 4th edition file server available
From: Richard Miller <miller@hamnavoe.demon.co.uk>
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Date: Mon, 13 Jan 2003 10:01:30 0000

> One advantage (as I understood it) of using a specialized kernel
> was a form of security -- there were *no* user mode programs
> whose bugs could be exploited.

It went further than that: you couldn't even exploit a buffer overflow
to exec a shell, because there was no shell and no exec.

Would it be feasible, as part of bootstrapping a minimal fossil
server, to remove or otherwise disable the exec system call
once everything was running?

-- Richard

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