On Wed, May 25, 2022 at 08:44:56PM +0200, Pablo Neira Ayuso wrote:
> On Wed, May 25, 2022 at 12:23:57PM -0400, wenxu@xxxxxxxxxxxxxxx wrote:
> > From: wenxu <wenxu@xxxxxxxxxxxxxxx>
> >
> > The nf_flow_tabel get route through ip_route_output_key which
> > the saddr should be local ones. For the forward case it always
> > can't get the other_dst and can't offload any flows
> >
> > Fixes: 3412e1641828 (netfilter: flowtable: nft_flow_route use more data for reverse route)
> > Signed-off-by: wenxu <wenxu@xxxxxxxxxxxxxxx>
> > ---
> > net/netfilter/nft_flow_offload.c | 2 --
> > 1 file changed, 2 deletions(-)
> >
> > diff --git a/net/netfilter/nft_flow_offload.c b/net/netfilter/nft_flow_offload.c
> > index 40d18aa..742a494 100644
> > --- a/net/netfilter/nft_flow_offload.c
> > +++ b/net/netfilter/nft_flow_offload.c
> > @@ -230,7 +230,6 @@ static int nft_flow_route(const struct nft_pktinfo *pkt,
> > switch (nft_pf(pkt)) {
> > case NFPROTO_IPV4:
> > fl.u.ip4.daddr = ct->tuplehash[dir].tuple.src.u3.ip;
> > - fl.u.ip4.saddr = ct->tuplehash[dir].tuple.dst.u3.ip;
>
> I think this should be instead:
>
> fl.u.ip4.saddr = ct->tuplehash[!dir].tuple.src.u3.ip;
>
> to accordingly deal with snat and dnat.
Hi,
I think what is actually missing here to cover all cases is:
fl.u.ip4.flowi4_flags = FLOWI_FLAG_ANYSRC;
and
fl.u.ip6.flowi6_flags = FLOWI_FLAG_ANYSRC;
this is used in other places in the kernel to fix this problem.
Do you want me to send a fix for that?
Best
Sven
>
> > fl.u.ip4.flowi4_oif = nft_in(pkt)->ifindex;
> > fl.u.ip4.flowi4_iif = this_dst->dev->ifindex;
> > fl.u.ip4.flowi4_tos = RT_TOS(ip_hdr(pkt->skb)->tos);
> > @@ -238,7 +237,6 @@ static int nft_flow_route(const struct nft_pktinfo *pkt,
> > break;
> > case NFPROTO_IPV6:
> > fl.u.ip6.daddr = ct->tuplehash[dir].tuple.src.u3.in6;
> > - fl.u.ip6.saddr = ct->tuplehash[dir].tuple.dst.u3.in6;
>
> fl.u.ip6.saddr = ct->tuplehash[!dir].tuple.src.u3.in6;
>
> > fl.u.ip6.flowi6_oif = nft_in(pkt)->ifindex;
> > fl.u.ip6.flowi6_iif = this_dst->dev->ifindex;
> > fl.u.ip6.flowlabel = ip6_flowinfo(ipv6_hdr(pkt->skb));
> > --
> > 1.8.3.1
> >
