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List:       openbsd-misc
Subject:    Re: Security(DoS) Problems with Inetd
From:       Marco S Hyman <marc () snafu ! org>
Date:       2001-02-28 18:44:52
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Dennis Davis writes:
 > >Many of you already know this from a posting(s) on either bugtrack or on
 > >NetBSD-users@. Attached with this mail is an exploit (DoS), that kills
 > >inetd processes. I have been able to reproduce this on:

Are you sure it kills inetd.  Inetd purposely closes down a service after n
connects per minute, where n defaults to 256.   Use the -R option
to inetd to change n on a global bases.

Also, if you look the man page you'll see that the syntax for inetd.conf
is "wait/nowait[.max]".    The man page says:

     inetd to check for new service requests to spawn new servers.  The op-
     tional ``max'' suffix (separated from ``wait'' or ``nowait'' by a dot)
     specifies the maximum number of server instances that may be spawned from
     inetd within an interval of 60 seconds.  When omitted, ``max'' defaults
     to 256.

Technically that is incorrect.   It should read something like

    "When omitted, ``max'' defaults to the value set with the -R option."

inetd does this by design.   Is it a DOS when a program works as designed,
is configurable to work differently, but wasn't configured?

// marc

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