fixup: sctp: verify size of a new chunk in _sctp_make_chunk()

Ben writes:
> > +	int chunklen;
> > +
> > +	chunklen = sizeof(*chunk_hdr) + paylen;
> 
> I think this length still needs to be rounded up (with WORD_ROUND here,
> instead of SCTP_PAD4 upstream).

So here's a fix for this problem.


Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>