[PATCH 5.5 025/120] netfilter: flowtable: Fix hardware flush order on nf_flow_table_cleanup

[Greg Kroah-Hartman]

From: Paul Blakey <paulb@xxxxxxxxxxxx>

commit 91bfaa15a379e9af24f71fb4ee08d8019b6e8ec7 upstream.

On netdev down event, nf_flow_table_cleanup() is called for the relevant
device and it cleans all the tables that are on that device.
If one of those tables has hardware offload flag,
nf_flow_table_iterate_cleanup flushes hardware and then runs the gc.
But the gc can queue more hardware work, which will take time to execute.

Instead first add the work, then flush it, to execute it now.

Fixes: c29f74e0df7a ("netfilter: nf_flow_table: hardware offload support")
Signed-off-by: Paul Blakey <paulb@xxxxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 net/netfilter/nf_flow_table_core.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/netfilter/nf_flow_table_core.c
+++ b/net/netfilter/nf_flow_table_core.c
@@ -529,9 +529,9 @@ static void nf_flow_table_do_cleanup(str
 static void nf_flow_table_iterate_cleanup(struct nf_flowtable *flowtable,
 					  struct net_device *dev)
 {
-	nf_flow_table_offload_flush(flowtable);
 	nf_flow_table_iterate(flowtable, nf_flow_table_do_cleanup, dev);
 	flush_delayed_work(&flowtable->gc_work);
+	nf_flow_table_offload_flush(flowtable);
 }
 
 void nf_flow_table_cleanup(struct net_device *dev)