ofp-packet: Fix NXT_RESUME with geneve tunnel metadata

The patch address vswitchd crash when it receives NXT_RESUME with geneve
tunnel metadata.  The crash is due to segmentation fault with the
following stack trace, and it is observed only in kernel datapath.
A test is added to prevent regression.

Thread 1 "ovs-vswitchd" received signal SIGSEGV, Segmentation fault.
0  0x00007fcffd0c5412 in tun_metadata_to_geneve__ (flow=flow@entry=0x7ffcb7106680, b=b@entry=0x7ffcb70eb5a8, crit_opt=crit_opt@entry=0x7ffcb70eb287)
   at lib/tun-metadata.c:676
1  0x00007fcffd0c6858 in tun_metadata_to_geneve_nlattr_flow (b=0x7ffcb70eb5a8, flow=0x7ffcb7106638) at lib/tun-metadata.c:706
2  tun_metadata_to_geneve_nlattr (tun=tun@entry=0x7ffcb7106638, flow=flow@entry=0x7ffcb7106638, key=key@entry=0x0, b=b@entry=0x7ffcb70eb5a8)
   at lib/tun-metadata.c:810
3  0x00007fcffd048464 in tun_key_to_attr (a=a@entry=0x7ffcb70eb5a8, tun_key=tun_key@entry=0x7ffcb7106638, tun_flow_key=tun_flow_key@entry=0x7ffcb7106638,
   key_buf=key_buf@entry=0x0, tnl_type=<optimized out>, tnl_type@entry=0x0) at lib/odp-util.c:2886
4  0x00007fcffd0551cf in odp_key_from_dp_packet (buf=buf@entry=0x7ffcb70eb5a8, packet=0x7ffcb7106590) at lib/odp-util.c:5909
5  0x00007fcffd0d7870 in dpif_netlink_encode_execute (buf=0x7ffcb70eb5a8, d_exec=0x7ffcb7106428, dp_ifindex=<optimized out>) at lib/dpif-netlink.c:1873
6  dpif_netlink_operate__ (dpif=dpif@entry=0xe65e00, ops=ops@entry=0x7ffcb7106418, n_ops=n_ops@entry=1) at lib/dpif-netlink.c:1959
7  0x00007fcffd0d842e in dpif_netlink_operate_chunks (n_ops=1, ops=0x7ffcb7106418, dpif=<optimized out>) at lib/dpif-netlink.c:2258
8  dpif_netlink_operate (dpif_=0xe65e00, ops=<optimized out>, n_ops=<optimized out>) at lib/dpif-netlink.c:2294
9  0x00007fcffd014680 in dpif_operate (dpif=<optimized out>, ops=<optimized out>, ops@entry=0x7ffcb7106418, n_ops=n_ops@entry=1) at lib/dpif.c:1359
10 0x00007fcffd014c58 in dpif_execute (dpif=<optimized out>, execute=execute@entry=0x7ffcb71064e0) at lib/dpif.c:1324
11 0x00007fcffd40d3e6 in nxt_resume (ofproto_=0xe6af50, pin=0x7ffcb7107150) at ofproto/ofproto-dpif.c:4885
12 0x00007fcffd3f88c3 in handle_nxt_resume (ofconn=ofconn@entry=0xf8c8f0, oh=oh@entry=0xf7ebd0) at ofproto/ofproto.c:3612
13 0x00007fcffd404a3b in handle_openflow__ (msg=0xeac460, ofconn=0xf8c8f0) at ofproto/ofproto.c:8137
14 handle_openflow (ofconn=0xf8c8f0, ofp_msg=0xeac460) at ofproto/ofproto.c:8258
15 0x00007fcffd3f4653 in ofconn_run (handle_openflow=0x7fcffd4046f0 <handle_openflow>, ofconn=0xf8c8f0) at ofproto/connmgr.c:1432
16 connmgr_run (mgr=0xe422f0, handle_openflow=handle_openflow@entry=0x7fcffd4046f0 <handle_openflow>) at ofproto/connmgr.c:363
17 0x00007fcffd3fdc76 in ofproto_run (p=0xe6af50) at ofproto/ofproto.c:1821
18 0x000000000040ca94 in bridge_run__ () at vswitchd/bridge.c:2939
19 0x0000000000411d44 in bridge_run () at vswitchd/bridge.c:2997
20 0x00000000004094fd in main (argc=12, argv=0x7ffcb71085b8) at vswitchd/ovs-vswitchd.c:119

(cherry-picked from commit bed941b)
Conflicts:
        lib/ofp-packet.c
(branch-2.9 doesn't have lib/ofp-packet.c. The relevant code is in ofp-util.c, so modified it.)

VMWare-BZ: #2210216
CC: Yi-Hung Wei <yihung.wei@gmail.com>
Signed-off-by: Numan Siddique <nusiddiq@redhat.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

lib/ofp-util.c

@@ -3453,6 +3453,7 @@ decode_nx_packet_in2(const struct ofp_header *oh, bool loose,
             error = oxm_decode_match(payload.msg, ofpbuf_msgsize(&payload),
                                      loose, tun_table, vl_mff_map,
                                      &pin->flow_metadata);
+            pin->flow_metadata.flow.tunnel.metadata.tab = tun_table;
             break;
 
         case NXPINT_USERDATA:
@@ -3618,6 +3619,7 @@ ofputil_decode_packet_in(const struct ofp_header *oh, bool loose,
         enum ofperr error = decode_nx_packet_in2(oh, loose, tun_table,
                                                  vl_mff_map, pin, &total_len,
                                                  &buffer_id, continuation);
+        pin->flow_metadata.flow.tunnel.metadata.tab = tun_table;
         if (error) {
             return error;
         }

tests/system-traffic.at

@@ -380,6 +380,46 @@ NS_CHECK_EXEC([at_ns0], [ping -s 3200 -q -c 3 -i 0.3 -w 2 10.1.1.100 | FORMAT_PI
 OVS_TRAFFIC_VSWITCHD_STOP
 AT_CLEANUP
 
+AT_SETUP([datapath - flow resume with geneve tun_metadata])
+OVS_CHECK_GENEVE()
+
+OVS_TRAFFIC_VSWITCHD_START()
+ADD_BR([br-underlay])
+
+ADD_NAMESPACES(at_ns0)
+
+dnl Set up underlay link from host into the namespace using veth pair.
+ADD_VETH(p0, at_ns0, br-underlay, "172.31.1.1/24")
+AT_CHECK([ip addr add dev br-underlay "172.31.1.100/24"])
+AT_CHECK([ip link set dev br-underlay up])
+
+dnl Set up tunnel endpoints on OVS outside the namespace and with a native
+dnl linux device inside the namespace.
+ADD_OVS_TUNNEL([geneve], [br0], [at_gnv0], [172.31.1.1], [10.1.1.100/24])
+ADD_NATIVE_TUNNEL([geneve], [ns_gnv0], [at_ns0], [172.31.1.100], [10.1.1.1/24],
+                  [vni 0])
+
+dnl Set up flows
+AT_DATA([flows.txt], [dnl
+table=0, arp action=NORMAL
+table=0, in_port=LOCAL icmp action=output:at_gnv0
+table=0, in_port=at_gnv0 icmp action=set_field:0xa->tun_metadata0,resubmit(,1)
+table=1, icmp action=controller(pause), resubmit(,2)
+table=2, tun_metadata0=0xa, icmp action=output:LOCAL
+])
+AT_CHECK([ovs-ofctl add-tlv-map br0 "{class=0xffff,type=0,len=4}->tun_metadata0"])
+AT_CHECK([ovs-ofctl add-flows br0 flows.txt])
+AT_CHECK([ovs-ofctl add-flow br-underlay "actions=normal"])
+
+AT_CHECK([ovs-ofctl monitor br0 resume --detach --no-chdir --pidfile=ovs-ofctl0.pid 2> ofctl_monitor0.log])
+
+NS_CHECK_EXEC([at_ns0], [ping -q -c 3 10.1.1.100 | FORMAT_PING], [0], [dnl
+3 packets transmitted, 3 received, 0% packet loss, time 0ms
+])
+
+OVS_TRAFFIC_VSWITCHD_STOP
+AT_CLEANUP
+
 AT_SETUP([datapath - ping over geneve6 tunnel])
 OVS_CHECK_GENEVE_UDP6ZEROCSUM()