From: lull@acm.org (John Lull)
Date: Fri, 22 Sep 95 13:52:27 PDT
To: herbs@interlog.com (Herb Sutter)
Subject: Re: Another Netscape Bug (and possible security hole)
In-Reply-To: <199509221341.JAA07664@gold.interlog.com>
Message-ID: <199509222051.NAA10687@ix.ix.netcom.com>
MIME-Version: 1.0
Content-Type: text/plain


On Fri, 22 Sep 1995 09:47:35 -0400, herbs@interlog.com (Herb Sutter)
wrote:
 
> Don't just look at this bug, though... check ALL your static buffers and
> include code to check for overflow writes.  For example, if Netscape is
> written in C or C++ and the above code uses strcpy(), you could change
> strcpy() to strncpy() everywhere (and then set the last char to null in case
> strncpy() didn't).  Your programmers will know what I mean.

Better yet, ban both strncpy and strncat.  Replace them with
differently-named routines (strbcpy and strbcat?) that, given a buffer
length, are GUARANTEED to always give you a properly terminated string
that (including the terminator) does not overflow the specified
buffer.

Even better, use a good string class that does all this automatically
all the time.