netfilter: flowtable: Add pending bit for offload work (2c889795) · Commits · 戴 / test

Gc step can queue offloaded flow del work or stats work. Those work items can race each other and a flow could be freed before the stats work is executed and querying it. To avoid that, add a pending bit that if a work exists for a flow don't queue another work for it. This will also avoid adding multiple stats works in case stats work didn't complete but gc step started again. Signed-off-by:

Paul Blakey <paulb@mellanox.com> Reviewed-by:

Roi Dayan <roid@mellanox.com> Signed-off-by:

Pablo Neira Ayuso <pablo@netfilter.org>

include/net/netfilter/nf_flow_table.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -127,6 +127,7 @@ enum nf_flow_flags {
		NF_FLOW_HW_DYING,
		NF_FLOW_HW_DEAD,
		NF_FLOW_HW_REFRESH,
		NF_FLOW_HW_PENDING,
		};

		enum flow_offload_type {

net/netfilter/nf_flow_table_offload.c

+7 −1

Original line number	Diff line number	Diff line
		@@ -817,6 +817,7 @@ static void flow_offload_work_handler(struct work_struct *work)
		WARN_ON_ONCE(1);
		}

		clear_bit(NF_FLOW_HW_PENDING, &offload->flow->flags);
		kfree(offload);
		}

		@@ -831,9 +832,14 @@ nf_flow_offload_work_alloc(struct nf_flowtable *flowtable,
		{
		struct flow_offload_work *offload;

		if (test_and_set_bit(NF_FLOW_HW_PENDING, &flow->flags))
		return NULL;

		offload = kmalloc(sizeof(struct flow_offload_work), GFP_ATOMIC);
		if (!offload)
		if (!offload) {
		clear_bit(NF_FLOW_HW_PENDING, &flow->flags);
		return NULL;
		}

		offload->cmd = cmd;
		offload->flow = flow;

Admin message