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| author |   Tonghao Zhang <xiangxia.m.yue@gmail.com> | 2020-08-12 17:56:39 +0800 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2020-08-13 15:53:30 -0700 |
| commit | 1f3a090b9033f69de380c03db3ea1a1015c850cf (patch) | |
| tree | 0643c4fad96851def0045117bee2dc4fe89ff94a /net/openvswitch/flow_table.c | |
| parent | af_packet: TPACKET_V3: fix fill status rwlock imbalance (diff) | |
| download | wireguard-linux-1f3a090b9033f69de380c03db3ea1a1015c850cf.tar.xz wireguard-linux-1f3a090b9033f69de380c03db3ea1a1015c850cf.zip | |
net: openvswitch: introduce common code for flushing flows
To avoid some issues, for example RCU usage warning and double free,
we should flush the flows under ovs_lock. This patch refactors
table_instance_destroy and introduces table_instance_flow_flush
which can be invoked by __dp_destroy or ovs_flow_tbl_flush.
Fixes: 50b0e61b32ee ("net: openvswitch: fix possible memleak on destroy flow-table")
Reported-by: Johan Knöös <jknoos@google.com>
Reported-at: https://mail.openvswitch.org/pipermail/ovs-discuss/2020-August/050489.html
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/openvswitch/flow_table.c')
| -rw-r--r-- | net/openvswitch/flow_table.c | 35 |
1 files changed, 15 insertions, 20 deletions
diff --git a/net/openvswitch/flow_table.c b/net/openvswitch/flow_table.c index 8c12675cbb67..e2235849a57e 100644 --- a/net/openvswitch/flow_table.c +++ b/net/openvswitch/flow_table.c @@ -473,19 +473,15 @@ static void table_instance_flow_free(struct flow_table *table, flow_mask_remove(table, flow->mask); } -static void table_instance_destroy(struct flow_table *table, - struct table_instance *ti, - struct table_instance *ufid_ti, - bool deferred) +/* Must be called with OVS mutex held. */ +void table_instance_flow_flush(struct flow_table *table, + struct table_instance *ti, + struct table_instance *ufid_ti) { int i; - if (!ti) - return; - - BUG_ON(!ufid_ti); if (ti->keep_flows) - goto skip_flows; + return; for (i = 0; i < ti->n_buckets; i++) { struct sw_flow *flow; @@ -497,18 +493,16 @@ static void table_instance_destroy(struct flow_table *table, table_instance_flow_free(table, ti, ufid_ti, flow, false); - ovs_flow_free(flow, deferred); + ovs_flow_free(flow, true); } } +} -skip_flows: - if (deferred) { - call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); - call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb); - } else { - __table_instance_destroy(ti); - __table_instance_destroy(ufid_ti); - } +static void table_instance_destroy(struct table_instance *ti, + struct table_instance *ufid_ti) +{ + call_rcu(&ti->rcu, flow_tbl_destroy_rcu_cb); + call_rcu(&ufid_ti->rcu, flow_tbl_destroy_rcu_cb); } /* No need for locking this function is called from RCU callback or @@ -523,7 +517,7 @@ void ovs_flow_tbl_destroy(struct flow_table *table) call_rcu(&mc->rcu, mask_cache_rcu_cb); call_rcu(&ma->rcu, mask_array_rcu_cb); - table_instance_destroy(table, ti, ufid_ti, false); + table_instance_destroy(ti, ufid_ti); } struct sw_flow *ovs_flow_tbl_dump_next(struct table_instance *ti, @@ -641,7 +635,8 @@ int ovs_flow_tbl_flush(struct flow_table *flow_table) flow_table->count = 0; flow_table->ufid_count = 0; - table_instance_destroy(flow_table, old_ti, old_ufid_ti, true); + table_instance_flow_flush(flow_table, old_ti, old_ufid_ti); + table_instance_destroy(old_ti, old_ufid_ti); return 0; err_free_ti: |