[ovs-dev] [PATCH] conntrack: Add coverage count for l4csum error.

[William Tu]

On Thu, Apr 16, 2020 at 10:35 AM Yi-Hung Wei <yihung.wei at gmail.com> wrote:
>
> On Thu, Apr 16, 2020 at 7:17 AM William Tu <u9012063 at gmail.com> wrote:
> >
> > Add a coverage counter when userspace conntrack receives a packet
> > with invalid l4 checksum.  When using veth for testing, users
> > often forget to turn off the tx offload on the other side of the
> > namespace, causing l4 checksum not calculated in packet header,
> > and at conntrack, return invalid conntrack state.
> >
> > Suggested-by: Yi-Hung Wei <yihung.wei at gmail.com>
> > Signed-off-by: William Tu <u9012063 at gmail.com>
> > ---
> >  lib/conntrack.c | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/lib/conntrack.c b/lib/conntrack.c
> > index 0cbc8f6d2b25..98a62ce3bae6 100644
> > --- a/lib/conntrack.c
> > +++ b/lib/conntrack.c
> > @@ -44,6 +44,7 @@ VLOG_DEFINE_THIS_MODULE(conntrack);
> >
> >  COVERAGE_DEFINE(conntrack_full);
> >  COVERAGE_DEFINE(conntrack_long_cleanup);
> > +COVERAGE_DEFINE(conntrack_l4csum_err);
> >
> >  struct conn_lookup_ctx {
> >      struct conn_key key;
> > @@ -1661,6 +1662,7 @@ checksum_valid(const struct conn_key *key, const void *data, size_t size,
> >      } else if (key->dl_type == htons(ETH_TYPE_IPV6)) {
> >          return packet_csum_upperlayer6(l3, data, key->nw_proto, size) == 0;
> >      } else {
> > +        COVERAGE_INC(conntrack_l4csum_err);
> >          return false;
> >      }
> >  }
> > --
>
> Hi William,
>
> I think this patch does count the l4 checksum error on tcp, udp and
> icmpv6.  But it does not cover the case of icmp v4.  Should we include
> the checksum error on icmp v4 as well?
>
OK I will add it.
William