Re: Buffer Overrun / DOS in /bin/passwd (at least Redhat Linux

From: Theo de Raadt (deraadtat_private)
Date: Fri Dec 19 1997 - 14:08:27 PST

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    In OpenBSD, we constrain the password line to be 1023 characters long
    (_including_ expansion in the gecos field of all cases of '&' ->
    username).
    
    Perhaps this strict constraint isn't the perfect solution to the
    problem, but it sure has stopped a few root holes.  One day we'll
    rewrite it better: allow longer lengths, but check in lots of places.
    (However a current benefit of this scheme is that the 1023 character
    constraint also helps for the YP server case).
    
    
    This solution saved us from the sendmail overflow in buildfname().
    



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