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To: "Lenzi, Sergio" <lenzi@bsi.com.br>
cc: freebsd-hackers@FreeBSD.ORG
Subject: Re: pppd problem when using natd (cont.). 
In-reply-to: Your message of "Fri, 06 Jun 1997 15:28:46 -0000."
             <Pine.BSF.3.91.970606152339.341A-100000@sergio> 
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Date: Fri, 06 Jun 1997 22:17:57 +0100
From: Brian Somers <brian@awfulhak.org>
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> 
> The panic on module ppp seems to be in pppfcs call.
> 
> The system panics while using natd (network address translator) and pppd
> 
> 
> (line 570 of file /usr/src/sys/net/ppp_tty.c).
> 
> It arises when ppp_fcs receive a len  less than zero.
> 
> static u_short
> pppfcs(fcs, cp, len)
>     register u_short fcs;
>     register u_char *cp;
>     register int len;
> {
>     while (len--)
> 	fcs = PPP_FCS(fcs, *cp++);
>     return (fcs);
> }
> 
> Can someone please guide me what to do if this function receives 
> len < 0 ???
> 
> In a test with a printf... it receives len = -17.
> 
> Thanks for any help.

Looks like the/a cause.  cp will get de-referenced until len
wraps - that means panic in my book.  I wonder why it's being
called with -17.  Are you able to commit, or would you like me
to take a look at fixing this (or Joerg, you've been in there
recently, do you want to wear the hat) ?

> Sergio Lenzi.
> 
> Unix consult.
> 

-- 
Brian <brian@awfulhak.org>, <brian@freebsd.org>
      <http://www.awfulhak.org>
Don't _EVER_ lose your sense of humour....