Re: [Qemu-devel] [PATCH] slirp: don't zero ti_i since we access it later.

["Tao Wu(吴涛@Eng)" <lepton@google.com>]

Thanks. Actually this is a follow up with my previous effort to fix this
bug.
I was busy on something else and then got lost in that old thread. Now I
just checked some my local patch
to see if they've merged to upstream and then found it out.

This is old thread about this:
http://lists.nongnu.org/archive/html/qemu-devel/2017-04/msg05544.html


On Thu, Nov 9, 2017 at 2:50 AM, Marc-André Lureau <
marcandre.lureau@gmail.com> wrote:

> Hi
>
> Adding Guillaume in CC, who wrote that line in commit 98c63057d2144
>
> On Wed, Nov 8, 2017 at 11:53 PM, Tao Wu via Qemu-devel
> <qemu-devel@nongnu.org> wrote:
> > The current code looks buggy, we zero ti_i while we access
> > ti_dst/ti_src later.
>
> Could you described the symptoms and why you fixed it that way?
>
> thanks
>
> >
> > Signed-off-by: Tao Wu <lepton@google.com>
> > ---
> >  slirp/tcp_subr.c | 11 ++++++++++-
> >  1 file changed, 10 insertions(+), 1 deletion(-)
> >
> > diff --git a/slirp/tcp_subr.c b/slirp/tcp_subr.c
> > index dc8b4bbb50..da0d53743f 100644
> > --- a/slirp/tcp_subr.c
> > +++ b/slirp/tcp_subr.c
> > @@ -148,7 +148,16 @@ tcp_respond(struct tcpcb *tp, struct tcpiphdr *ti,
> struct mbuf *m,
> >                 m->m_data += IF_MAXLINKHDR;
> >                 *mtod(m, struct tcpiphdr *) = *ti;
> >                 ti = mtod(m, struct tcpiphdr *);
> > -               memset(&ti->ti, 0, sizeof(ti->ti));
> > +               switch (af) {
> > +               case AF_INET:
> > +                   ti->ti.ti_i4.ih_x1 = 0;
> > +                   break;
> > +               case AF_INET6:
> > +                   ti->ti.ti_i6.ih_x1 = 0;
> > +                   break;
> > +               default:
> > +                   g_assert_not_reached();
> > +               }
> >                 flags = TH_ACK;
> >         } else {
> >                 /*
> > --
> > 2.15.0.448.gf294e3d99a-goog
> >
> >
>
>
>
> --
> Marc-André Lureau
>