> Date: Mon, 20 Aug 2018 11:05:08 -0700
> From: Ori Bernstein <o...@eigenstate.org>
>
> > As far as I know, switch(4) assumes it receives packets located at 64
> > bit aligned memory. So if the code like below
> >
> > *(uint64_t *)oxm->oxm_value = htobe64(val);
> >
> > cause alignment faults, the assumption may be broken. If so, the
> > place we should fix may not be here.
>
> The reason we are suspicious here is because oxm_value comes from struct
> ofp_ox_match, which is defined like this:
>
> struct ofp_ox_match {
> uint16_t oxm_class;
> uint8_t oxm_fh;
> uint8_t oxm_length;
> uint8_t oxm_value[0];
> } __packed;
This means that unless ofp_ox_match is by some magic aligned on an odd
32-bit boundary, oxm_value is not aligned on a 64-bit boundary. So a cast to
quint64_t * is broken.
