[PATCH net] netfilter: flowtable: Fix flushing of offloaded flows on free

[PATCH net] netfilter: flowtable: Fix flushing of offloaded flows on free

[Paul Blakey]

Freeing a flowtable with offloaded flows, the flow are deleted from
hardware but are not deleted from the flow table, leaking them,
and leaving their offload bit on.

Add a second pass of the disabled gc to delete the these flows from
the flow table before freeing it.

Fixes: c29f74e0df7a ("netfilter: nf_flow_table: hardware offload support")
Signed-off-by: Paul Blakey <paulb@mellanox.com>
---
 net/netfilter/nf_flow_table_core.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/netfilter/nf_flow_table_core.c b/net/netfilter/nf_flow_table_core.c
index 8af28e1..70ebeba 100644
--- a/net/netfilter/nf_flow_table_core.c
+++ b/net/netfilter/nf_flow_table_core.c
@@ -554,6 +554,9 @@ void nf_flow_table_free(struct nf_flowtable *flow_table)
 	nf_flow_table_iterate(flow_table, nf_flow_table_do_cleanup, NULL);
 	nf_flow_table_iterate(flow_table, nf_flow_offload_gc_step, flow_table);
 	nf_flow_table_offload_flush(flow_table);
+	if (nf_flowtable_hw_offload(flow_table))
+		nf_flow_table_iterate(flow_table, nf_flow_offload_gc_step,
+				      flow_table);
 	rhashtable_destroy(&flow_table->rhashtable);
 }
 EXPORT_SYMBOL_GPL(nf_flow_table_free);
-- 
1.8.3.1

Re: [PATCH net] netfilter: flowtable: Fix flushing of offloaded flows on free

[Pablo Neira Ayuso]

On Thu, Mar 19, 2020 at 11:52:25AM +0200, Paul Blakey wrote:
> Freeing a flowtable with offloaded flows, the flow are deleted from
> hardware but are not deleted from the flow table, leaking them,
> and leaving their offload bit on.
> 
> Add a second pass of the disabled gc to delete the these flows from
> the flow table before freeing it.

Applied, thanks.