Hi, Thanks for the review.
Mark Gray <[email protected]> 于2021年2月17日周三 下午6:13写道： > > I'm not too familiar with this code but I have some comments. > > On 15/02/2021 09:50, Peng He wrote: > > CT zone could be set from a field that is not included in frozen > > metedata. Consider the belowing cases which is normally used in > > Nits: > > s/metedata/metadata > s/belowing cases which is/cases below which are sorry for the typo, will fix it in the next version > > > OpenStack security group rules: > > > > priority=100,in_port=1,tcp,ct_state=-trk,action=ct(zone=5,table=0) > > priority=100,in_port=1,tcp,ct_state=+trk,action=ct(commit,zone=NXM_NX_CT_ZONE[]),2 > > > > The zone is set from the first rule's ct action. These two rules will > > generate two megaflows: the first one uses zone=5 to query the CT module, > > the second one set zone from the first megaflow and commit to CT. > > > > The current implementation will generate a megaflow which does not use > > ct_zone=5 as a match, but directly commit into the ct using zone=5, as zone > > is > > set by an Imm not a field. > > > > Consider a situation that one changes the zone id (for example to 15) > > in the first rule however still keep the second rule unchanged. During > > this change, there is traffic hitting the two generated megaflows, the > > revaldiator would revalidate all megaflows, however, the revalidator will > > not change the second megaflow, because zone=5 is recorded in the > > megaflow, so the xlate will still translate the commit action into zone=5, > > and the new traffic will still commit to CT as zone=5, not zone=15, > > resulting in taffic drops and other issues. > > > > Just like OVS set-field action, if the field X is set by Y, we should also > > mask Y as a match in the generated megaflow. An exception is that, if the > > zone > > is set by the field that is included in the frozen state and this upcall is > > a resume of a thawed xlate, the masking can be skipped, as if one changes > > the previous rule, the generated recirc_id will be changed, and all > > megaflows > > with the old recirc id will be invalid later, i.e. the revalidator will > > not reuse the old megaflows at all. > > > > Fixes: 07659514c3 ("Add support for connection tracking.") > > Reported-by: Sai Su <[email protected]> > > Signed-off-by: Peng He <[email protected]> > > --- > > include/openvswitch/meta-flow.h | 1 + > > lib/meta-flow.c | 13 +++++++++++ > > ofproto/ofproto-dpif-xlate.c | 15 +++++++++++++ > > tests/system-traffic.at | 39 +++++++++++++++++++++++++++++++++ > > 4 files changed, 68 insertions(+) > > > > diff --git a/include/openvswitch/meta-flow.h > > b/include/openvswitch/meta-flow.h > > index 95e52e358..045dce8f5 100644 > > --- a/include/openvswitch/meta-flow.h > > +++ b/include/openvswitch/meta-flow.h > > @@ -2305,6 +2305,7 @@ void mf_set_flow_value_masked(const struct mf_field *, > > const union mf_value *mask, > > struct flow *); > > bool mf_is_tun_metadata(const struct mf_field *); > > +bool mf_is_frozen_metadata(const struct mf_field *); > > bool mf_is_pipeline_field(const struct mf_field *); > > bool mf_is_set(const struct mf_field *, const struct flow *); > > void mf_mask_field(const struct mf_field *, struct flow_wildcards *); > > diff --git a/lib/meta-flow.c b/lib/meta-flow.c > > index c808d205d..e03cd8d0c 100644 > > --- a/lib/meta-flow.c > > +++ b/lib/meta-flow.c > > @@ -1788,6 +1788,19 @@ mf_is_tun_metadata(const struct mf_field *mf) > > mf->id < MFF_TUN_METADATA0 + TUN_METADATA_NUM_OPTS; > > } > > > > +bool > > +mf_is_frozen_metadata(const struct mf_field *mf) > > +{ > > + if (mf->id >= MFF_TUN_ID && mf->id <= MFF_IN_PORT_OXM) { > > + return true; > > + } > > + > > + if (mf->id >= MFF_REG0 && mf->id < MFF_ETH_SRC) { > > + return true; > > + } > > + return false; > > +} > > + > > bool > > mf_is_pipeline_field(const struct mf_field *mf) > > { > > diff --git a/ofproto/ofproto-dpif-xlate.c b/ofproto/ofproto-dpif-xlate.c > > index 7108c8a30..5d1f029fd 100644 > > --- a/ofproto/ofproto-dpif-xlate.c > > +++ b/ofproto/ofproto-dpif-xlate.c > > @@ -6212,6 +6212,21 @@ compose_conntrack_action(struct xlate_ctx *ctx, > > struct ofpact_conntrack *ofc, > > &ctx->xin->flow, ctx->wc, zone); > > } > > } > > + > > + if (ofc->zone_src.field) { > > + if (ctx->xin->frozen_state) { > > + /* If the upcall is a resume of a recirculation, we only need > > to > > + * unwildcard the fields that are not in the frozen_metadata, > > as > > + * when the rules update, OVS will generate a new recirc_id, > > + * which will invalidate the megaflow with old the recirc_id. > > + */ > > + if (!mf_is_frozen_metadata(ofc->zone_src.field)) { > > + mf_mask_field(ofc->zone_src.field, ctx->wc); > Is this the only field we should check and un-wildcard here. This seems > like it would be applicable across other fields. if you mean that we should strictly limit the un-wildcarded fields to the subfield of the zone_src, not all the subfields of it, then yes. I think here we only extended to the field pointed by zone_src, not across other fields. > > + } > > + } else { > > + mf_mask_field(ofc->zone_src.field, ctx->wc); > > + } > > + } > > Add a new line after the bracket > > > nl_msg_put_u16(ctx->odp_actions, OVS_CT_ATTR_ZONE, zone); > > put_ct_mark(&ctx->xin->flow, ctx->odp_actions, ctx->wc); > > put_ct_label(&ctx->xin->flow, ctx->odp_actions, ctx->wc); > > diff --git a/tests/system-traffic.at b/tests/system-traffic.at > > index fb5b9a36d..bee50e530 100644 > > --- a/tests/system-traffic.at > > +++ b/tests/system-traffic.at > > @@ -1927,6 +1927,45 @@ > > tcp,orig=(src=10.1.1.3,dst=10.1.1.4,sport=<cleared>,dport=<cleared>),reply=(src= > > OVS_TRAFFIC_VSWITCHD_STOP > > AT_CLEANUP > > > > +AT_SETUP([conntrack - zones from other field]) > > +CHECK_CONNTRACK() > > +OVS_TRAFFIC_VSWITCHD_START() > > + > > +ADD_NAMESPACES(at_ns0, at_ns1) > > + > > +ADD_VETH(p0, at_ns0, br0, "10.1.1.1/24") > > +ADD_VETH(p1, at_ns1, br0, "10.1.1.2/24") > > + > > +dnl Allow any traffic from ns0->ns1. Only allow nd, return traffic from > > ns1->ns0. > > +AT_DATA([flows.txt], [dnl > > +priority=1,action=drop > > +priority=10,arp,action=normal > > +priority=10,icmp,action=normal > > +priority=100,in_port=1,tcp,ct_state=-trk,action=ct(zone=5,table=0) > > +priority=100,in_port=1,tcp,ct_state=+trk,action=ct(commit,zone=NXM_NX_CT_ZONE[]),2 > > +priority=100,in_port=2,ct_state=-trk,tcp,action=ct(table=0,zone=5) > > +priority=100,in_port=2,ct_state=+trk,ct_zone=5,tcp,action=1 > > +]) > > + > > +AT_CHECK([ovs-ofctl --bundle add-flows br0 flows.txt]) > > + > > +OVS_START_L7([at_ns1], [http]) > > + > > +dnl HTTP requests from p0->p1 should work fine. > > +NS_CHECK_EXEC([at_ns0], [wget 10.1.1.2 -t 3 -T 1 --retry-connrefused -v -o > > wget0.log]) > > + > > +AT_CHECK([ovs-appctl dpctl/dump-conntrack | FORMAT_CT(10.1.1.2)], [0], [dnl > > +tcp,orig=(src=10.1.1.1,dst=10.1.1.2,sport=<cleared>,dport=<cleared>),reply=(src=10.1.1.2,dst=10.1.1.1,sport=<cleared>,dport=<cleared>),zone=5,protoinfo=(state=<cleared>) > > +]) > > + > > +AT_CHECK([ovs-appctl dpctl/dump-flows --names filter=in_port=ovs-p0 | > > strip_used | grep "+trk" ], [0], [dnl > > +ct_state(+trk),ct_zone(0x5),recirc_id(0x2),in_port(ovs-p0),packet_type(ns=0,id=0),eth_type(0x0800),ipv4(proto=6,frag=no), > > packets:5, bytes:465, used:0.0s, flags:FP., > > actions:ct(commit,zone=5),ovs-p1 > > +]) > > This test fails for me. It looks like the order of the output from > dpctl/dump-flows is different and the recirc_id is different. Could > easily be an issue on my side but I am not sure what it is. > > +++ /home/magray/ovs/tests/system-kmod-testsuite.dir/at-groups/41/stdout > 2021-02-17 04:57:36.171766685 -0500 > @@ -1,2 +1,2 @@ > -ct_state(+trk),ct_zone(0x5),recirc_id(0x2),in_port(ovs-p0),packet_type(ns=0,id=0),eth_type(0x0800),ipv4(proto=6,frag=no), > packets:5, bytes:465, used:0.0s, flags:FP., actions:ct(commit,zone=5),ovs-p1 > +recirc_id(0x1),in_port(ovs-p0),ct_state(+trk),ct_zone(0x5),eth(),eth_type(0x0800),ipv4(proto=6,frag=no), > packets:5, bytes:465, used:0.0s, flags:FP., actions:ct(commit,zone=5),ovs-p1 > yes, the problem is the recirc_id, looks like we need a similar function like stirp_used, (strip_recirc_id) The case is to make sure that the ct_zone(0x5) should show up in the match. > It seems this test does not test the situation that you mention in the > commit message: "Consider a situation .. "? Can you add a check for that? The commit describes how we discover the bug, but essentially this is just following the convention that when you try to load Y to X, (both Y and X are variable, not a Imm) you should un-wildcard Y in xlate process. I would like to add the check in the test suites, but I do not know if the current test framework provides enough tools for that. Will try to add the check in v2. > > > + > > +OVS_TRAFFIC_VSWITCHD_STOP > > +AT_CLEANUP > > + > > + > > AT_SETUP([conntrack - multiple bridges]) > > CHECK_CONNTRACK() > > OVS_TRAFFIC_VSWITCHD_START( > > > -- hepeng _______________________________________________ dev mailing list [email protected] https://mail.openvswitch.org/mailman/listinfo/ovs-dev
