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Date:      Tue, 29 Jun 1999 00:39:09 -0700 (PDT)
From:      "Brian W. Buchanan" <brian@CSUA.Berkeley.EDU>
To:        "Vladimir Mencl, MK, susSED" <mencl@nenya.ms.mff.cuni.cz>
Cc:        security@FreeBSD.ORG
Subject:   Re: ssh from windows
Message-ID:  <Pine.BSF.4.05.9906290036260.78068-100000@smarter.than.nu>
In-Reply-To: <Pine.SO4.4.05.9906290827060.2031-100000@nenya>

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On Tue, 29 Jun 1999, Vladimir Mencl, MK, susSED wrote:

>    BTW, is there any way of limiting attaching to system processes at
> higher securelevels? I was thinking about attaching to init (because
> "init can lower securelevel"), but I received a "permission denied" at
> securelevel 2, and a signal 11 at securelevel -1 ???? I don't know why,
> I received it not only in 'gdb `which init` 1', but also in a later
> 'gdb `which gdb` gdb.core'    ... is init protected against debugging 
> in a special way?

Yes, init cannot be attached to by a debugger when securelevel > 0.  This
change was made a good while back after I pointed out that it was possible
to lower the securelevel by this method.  I believe that the kernel was
also later changed to not allow the securelevel to be lowered by any
process, period.  I don't think it should be causing gdb to crash, though.

-- 
Brian Buchanan                                     brian@CSUA.Berkeley.EDU
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