net/sched: act_ct: Fix flow table lookup failure with no originating ifindex
authorPaul Blakey <paulb@nvidia.com>
Mon, 28 Feb 2022 09:23:49 +0000 (11:23 +0200)
committerPablo Neira Ayuso <pablo@netfilter.org>
Tue, 1 Mar 2022 21:08:31 +0000 (22:08 +0100)
After cited commit optimizted hw insertion, flow table entries are
populated with ifindex information which was intended to only be used
for HW offload. This tuple ifindex is hashed in the flow table key, so
it must be filled for lookup to be successful. But tuple ifindex is only
relevant for the netfilter flowtables (nft), so it's not filled in
act_ct flow table lookup, resulting in lookup failure, and no SW
offload and no offload teardown for TCP connection FIN/RST packets.

To fix this, add new tc ifindex field to tuple, which will
only be used for offloading, not for lookup, as it will not be
part of the tuple hash.

Fixes: 9795ded7f924 ("net/sched: act_ct: Fill offloading tuple iifidx")
Signed-off-by: Paul Blakey <paulb@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
include/net/netfilter/nf_flow_table.h
net/netfilter/nf_flow_table_offload.c
net/sched/act_ct.c

index a3647fa..bd59e95 100644 (file)
@@ -96,6 +96,7 @@ enum flow_offload_xmit_type {
        FLOW_OFFLOAD_XMIT_NEIGH,
        FLOW_OFFLOAD_XMIT_XFRM,
        FLOW_OFFLOAD_XMIT_DIRECT,
+       FLOW_OFFLOAD_XMIT_TC,
 };
 
 #define NF_FLOW_TABLE_ENCAP_MAX                2
@@ -127,7 +128,7 @@ struct flow_offload_tuple {
        struct { }                      __hash;
 
        u8                              dir:2,
-                                       xmit_type:2,
+                                       xmit_type:3,
                                        encap_num:2,
                                        in_vlan_ingress:2;
        u16                             mtu;
@@ -142,6 +143,9 @@ struct flow_offload_tuple {
                        u8              h_source[ETH_ALEN];
                        u8              h_dest[ETH_ALEN];
                } out;
+               struct {
+                       u32             iifidx;
+               } tc;
        };
 };
 
index b561e0a..fc4265a 100644 (file)
@@ -110,7 +110,11 @@ static int nf_flow_rule_match(struct nf_flow_match *match,
                nf_flow_rule_lwt_match(match, tun_info);
        }
 
-       key->meta.ingress_ifindex = tuple->iifidx;
+       if (tuple->xmit_type == FLOW_OFFLOAD_XMIT_TC)
+               key->meta.ingress_ifindex = tuple->tc.iifidx;
+       else
+               key->meta.ingress_ifindex = tuple->iifidx;
+
        mask->meta.ingress_ifindex = 0xffffffff;
 
        if (tuple->encap_num > 0 && !(tuple->in_vlan_ingress & BIT(0)) &&
index 33e70d6..ec19f62 100644 (file)
@@ -361,6 +361,13 @@ static void tcf_ct_flow_table_put(struct tcf_ct_params *params)
        }
 }
 
+static void tcf_ct_flow_tc_ifidx(struct flow_offload *entry,
+                                struct nf_conn_act_ct_ext *act_ct_ext, u8 dir)
+{
+       entry->tuplehash[dir].tuple.xmit_type = FLOW_OFFLOAD_XMIT_TC;
+       entry->tuplehash[dir].tuple.tc.iifidx = act_ct_ext->ifindex[dir];
+}
+
 static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
                                  struct nf_conn *ct,
                                  bool tcp)
@@ -385,10 +392,8 @@ static void tcf_ct_flow_table_add(struct tcf_ct_flow_table *ct_ft,
 
        act_ct_ext = nf_conn_act_ct_ext_find(ct);
        if (act_ct_ext) {
-               entry->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.iifidx =
-                       act_ct_ext->ifindex[IP_CT_DIR_ORIGINAL];
-               entry->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.iifidx =
-                       act_ct_ext->ifindex[IP_CT_DIR_REPLY];
+               tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_ORIGINAL);
+               tcf_ct_flow_tc_ifidx(entry, act_ct_ext, FLOW_OFFLOAD_DIR_REPLY);
        }
 
        err = flow_offload_add(&ct_ft->nf_ft, entry);