[krbdev.mit.edu #6475] Adding keys to malformed keytabs can infinitely extend the file

[Roland C. Dowdeswell via RT]

On 1240417069 seconds since the Beginning of the UNIX epoch
"krb5" wrote:
>

>+	    bufsiz = (*size_needed + sizeof(krb5_int32));

As it turns out, I made a quite similar mistake.  This line should
actually be:

	    bufsiz = (*size_needed + sizeof(krb5_int32)) - size;

In order to take care of what we've already written.

It might also be better to just fseek(3) out to the right place
and slap the sizeof(krb5_int32) zeros in place and fseek(3) back
to where we originally were.  That would be much more clear but I
didn't read the standards to see if that would be properly portable.

--
    Roland Dowdeswell                      http://Imrryr.ORG/~elric/