openvswitch: Fix kernel panic on ovs_flow_free
Both mega flow mask's reference counter and per flow table mask list
should only be accessed when holding ovs_mutex() lock. However
this is not true with ovs_flow_table_flush(). The patch fixes this bug.
Reported-by: Joe Stringer <joestringer@nicira.com>
Signed-off-by: Andy Zhou <azhou@nicira.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
diff --git a/net/openvswitch/datapath.c b/net/openvswitch/datapath.c
index d1a73a6..e1b337e 100644
--- a/net/openvswitch/datapath.c
+++ b/net/openvswitch/datapath.c
@@ -55,6 +55,7 @@
#include "datapath.h"
#include "flow.h"
+#include "flow_table.h"
#include "flow_netlink.h"
#include "vport-internal_dev.h"
#include "vport-netdev.h"
@@ -160,7 +161,6 @@
{
struct datapath *dp = container_of(rcu, struct datapath, rcu);
- ovs_flow_tbl_destroy(&dp->table);
free_percpu(dp->stats_percpu);
release_net(ovs_dp_get_net(dp));
kfree(dp->ports);
@@ -1287,7 +1287,7 @@
err_destroy_percpu:
free_percpu(dp->stats_percpu);
err_destroy_table:
- ovs_flow_tbl_destroy(&dp->table);
+ ovs_flow_tbl_destroy(&dp->table, false);
err_free_dp:
release_net(ovs_dp_get_net(dp));
kfree(dp);
@@ -1314,10 +1314,13 @@
list_del_rcu(&dp->list_node);
/* OVSP_LOCAL is datapath internal port. We need to make sure that
- * all port in datapath are destroyed first before freeing datapath.
+ * all ports in datapath are destroyed first before freeing datapath.
*/
ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
+ /* RCU destroy the flow table */
+ ovs_flow_tbl_destroy(&dp->table, true);
+
call_rcu(&dp->rcu, destroy_dp_rcu);
}