From 120075357a624293d52a1905c47a1bd249d2157c Mon Sep 17 00:00:00 2001 From: Xavier Simonart Date: Fri, 8 Dec 2023 13:44:10 +0100 Subject: [PATCH] controller: fixed potential segfault when changing tunnel_key and deleting ls. When a tunnel_key for a datapath was changed, the local_datapaths hmap was not properly updated as the old/initial entry was not removed. - If the datapath was not deleted at the same time, a new entry (for the same dp) was created in the local_datapaths as the previous entry was not found (wrong hash). - If the datapath was deleted at the same time, the former entry also remained (as, again, the hash was wrong). So, we kept a deleted (dp) entry in the hmap, and might crash when we used it later. When tunnel_key is updated for an existing datapath, we now clean the local_datapaths, removing bad entries (i.e entries for which the hash is not the tunnel_key). This issue was identified by flaky failures of test "ovn-ic -- route deletion upon TS deletion". Backtrace: 0 0x0000000000504a9a in hmap_first_with_hash (hmap=0x20f4d90, hmap@entry=0x5d5634, hmap=0x20f4d90, hmap@entry=0x5d5634, hash=1956414673) at ./include/openvswitch/hmap.h:360 1 smap_find__ (smap=smap@entry=0x20f4d90, key=key@entry=0x5d5634 "snat-ct-zone", key_len=key_len@entry=12, hash=1956414673) at lib/smap.c:421 2 0x0000000000505073 in smap_get_node (key=0x5d5634 "snat-ct-zone", smap=0x20f4d90) at lib/smap.c:217 3 smap_get_def (def=0x0, key=0x5d5634 "snat-ct-zone", smap=0x20f4d90) at lib/smap.c:208 4 smap_get (smap=0x20f4d90, key=key@entry=0x5d5634 "snat-ct-zone") at lib/smap.c:200 5 0x0000000000419898 in get_common_nat_zone (ldp=0x20a8c40, ldp=0x20a8c40) at controller/lflow.c:831 6 add_matches_to_flow_table (lflow=lflow@entry=0x21ddf90, ldp=ldp@entry=0x20a8c40, matches=matches@entry=0x211bb50, ptable=ptable@entry=10 '\n', output_ptable=output_ptable@entry=37 '%', ovnacts=ovnacts@entry=0x7ffd19b99de0, ingress=true, l_ctx_in=0x7ffd19b9a300, l_ctx_out=0x7ffd19b9a2c0) at controller/lflow.c:892 7 0x000000000041a29b in consider_logical_flow__ (lflow=lflow@entry=0x21ddf90, dp=0x20eb720, l_ctx_in=l_ctx_in@entry=0x7ffd19b9a300, l_ctx_out=l_ctx_out@entry=0x7ffd19b9a2c0) at controller/lflow.c:1207 8 0x000000000041a587 in consider_logical_flow (lflow=lflow@entry=0x21ddf90, is_recompute=is_recompute@entry=false, l_ctx_in=l_ctx_in@entry=0x7ffd19b9a300, l_ctx_out=l_ctx_out@entry=0x7ffd19b9a2c0) at controller/lflow.c:1276 9 0x000000000041e30f in lflow_handle_changed_flows (l_ctx_in=l_ctx_in@entry=0x7ffd19b9a300, l_ctx_out=l_ctx_out@entry=0x7ffd19b9a2c0) at controller/lflow.c:271 10 0x0000000000439fc7 in lflow_output_sb_logical_flow_handler (node=0x7ffd19ba5b70, data=) at controller/ovn-controller.c:4045 11 0x00000000004682fe in engine_compute (recompute_allowed=, node=) at lib/inc-proc-eng.c:441 12 engine_run_node (recompute_allowed=true, node=0x7ffd19ba5b70) at lib/inc-proc-eng.c:503 13 engine_run (recompute_allowed=recompute_allowed@entry=true) at lib/inc-proc-eng.c:528 14 0x000000000040ade2 in main (argc=, argv=) at controller/ovn-controller.c:5709 Signed-off-by: Xavier Simonart Signed-off-by: Dumitru Ceara (cherry picked from commit 425f699e2b20393ed136b381592a0beff19c06dc) --- controller/local_data.c | 14 ++++++++++++ controller/local_data.h | 4 ++++ controller/ovn-controller.c | 23 ++++++++++++++++++++ tests/ovn.at | 43 +++++++++++++++++++++++++++++++++++++ 4 files changed, 84 insertions(+) diff --git a/controller/local_data.c b/controller/local_data.c index 3a7d3afebe..ab18386c76 100644 --- a/controller/local_data.c +++ b/controller/local_data.c @@ -56,6 +56,20 @@ static bool datapath_is_transit_switch(const struct sbrec_datapath_binding *); static uint64_t local_datapath_usage; +/* To be used when hmap_node.hash might be wrong e.g. tunnel_key got updated */ +struct local_datapath * +get_local_datapath_no_hash(const struct hmap *local_datapaths, + uint32_t tunnel_key) +{ + struct local_datapath *ld; + HMAP_FOR_EACH (ld, hmap_node, local_datapaths) { + if (ld->datapath->tunnel_key == tunnel_key) { + return ld; + } + } + return NULL; +} + struct local_datapath * get_local_datapath(const struct hmap *local_datapaths, uint32_t tunnel_key) { diff --git a/controller/local_data.h b/controller/local_data.h index f6d8f725f8..2a1a3c0f95 100644 --- a/controller/local_data.h +++ b/controller/local_data.h @@ -69,6 +69,10 @@ struct local_datapath *local_datapath_alloc( const struct sbrec_datapath_binding *); struct local_datapath *get_local_datapath(const struct hmap *, uint32_t tunnel_key); +struct local_datapath *get_local_datapath_no_hash( + const struct hmap *local_datapaths, + uint32_t tunnel_key); + bool need_add_peer_to_local( struct ovsdb_idl_index *sbrec_port_binding_by_name, diff --git a/controller/ovn-controller.c b/controller/ovn-controller.c index 8ef74be26c..6787dda801 100644 --- a/controller/ovn-controller.c +++ b/controller/ovn-controller.c @@ -1912,6 +1912,7 @@ runtime_data_sb_datapath_binding_handler(struct engine_node *node OVS_UNUSED, engine_get_input("SB_datapath_binding", node)); const struct sbrec_datapath_binding *dp; struct ed_type_runtime_data *rt_data = data; + struct local_datapath *ld; SBREC_DATAPATH_BINDING_TABLE_FOR_EACH_TRACKED (dp, dp_table) { if (sbrec_datapath_binding_is_deleted(dp)) { @@ -1919,6 +1920,28 @@ runtime_data_sb_datapath_binding_handler(struct engine_node *node OVS_UNUSED, dp->tunnel_key)) { return false; } + /* If the tunnel key got updated, get_local_datapath will not find + * the ld. Use get_local_datapath_no_hash which does not + * rely on the hash. + */ + if (sbrec_datapath_binding_is_updated( + dp, SBREC_DATAPATH_BINDING_COL_TUNNEL_KEY)) { + if (get_local_datapath_no_hash(&rt_data->local_datapaths, + dp->tunnel_key)) { + return false; + } + } + } else if (sbrec_datapath_binding_is_updated( + dp, SBREC_DATAPATH_BINDING_COL_TUNNEL_KEY) + && !sbrec_datapath_binding_is_new(dp)) { + /* If the tunnel key is updated, remove the entry (with a wrong + * hash) from the map. It will be (properly) added back later. + */ + if ((ld = get_local_datapath_no_hash(&rt_data->local_datapaths, + dp->tunnel_key))) { + hmap_remove(&rt_data->local_datapaths, &ld->hmap_node); + local_datapath_destroy(ld); + } } } diff --git a/tests/ovn.at b/tests/ovn.at index a837a4471d..13f5575bed 100644 --- a/tests/ovn.at +++ b/tests/ovn.at @@ -37360,3 +37360,46 @@ OVN_CLEANUP([hv1]) AT_CLEANUP ]) + +OVN_FOR_EACH_NORTHD([ +AT_SETUP([Changing tunnel_key]) +ovn_start + +net_add n1 + +sim_add hv1 +as hv1 +check ovs-vsctl add-br br-phys +ovn_attach n1 br-phys 192.168.0.11 + +check ovn-nbctl --wait=hv ls-add ls \ + -- lsp-add ls lsp1 \ + -- lsp-add ls ls-lr \ + -- lr-add lr \ + -- lrp-add lr lr-ls f0:00:00:00:00:f1 192.168.1.1/24 \ + -- set Logical_Switch_Port ls-lr \ + type=router \ + options:router-port=lr-ls \ + addresses=router \ + -- lrp-set-gateway-chassis lr-ls hv1 + +sleep_controller hv1 + +check ovn-nbctl --wait=sb set Logical_Switch ls other_config:requested-tnl-key=1000 +check ovn-nbctl --wait=sb ls-del ls +wake_up_controller hv1 + +check ovn-nbctl --wait=hv sync + +check ovn-nbctl --wait=hv ls-add ls1 \ + -- lsp-add ls1 ls1-lr \ + -- lrp-add lr lr-ls1 f0:00:00:00:00:f2 192.168.2.1/24 \ + -- set Logical_Switch_Port ls1-lr type=router options:router-port=lr-ls1 addresses=router \ + -- lrp-set-gateway-chassis lr-ls1 hv1 + +check ovn-nbctl --wait=hv set Logical_Switch ls1 other_config:requested-tnl-key=1001 + +OVN_CLEANUP([hv1]) + +AT_CLEANUP +])