net: ethernet: mtk_eth_soc: avoid creating duplicate offload entries

Sometimes multiple CLS_REPLACE calls are issued for the same connection.
rhashtable_insert_fast does not check for these duplicates, so multiple
hardware flow entries can be created.
Fix this by checking for an existing entry early

Fixes: 502e84e2382d ("net: ethernet: mtk_eth_soc: add flow offloading support")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Ilya Lipnitskiy <ilya.lipnitskiy@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/mediatek/mtk_ppe_offload.c b/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
index b5f68f66d42a8f9125a16f0f7e29f777a4838344..7bb1f20002b582dfa8e5afdcac82d2b3bc3a4b35 100644 (file)
--- a/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
+++ b/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
@@ -186,6 +186,9 @@ mtk_flow_offload_replace(struct mtk_eth *eth, struct flow_cls_offload *f)
        int hash;
        int i;
 
+       if (rhashtable_lookup(&eth->flow_table, &f->cookie, mtk_flow_ht_params))
+               return -EEXIST;
+
        if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_META)) {
                struct flow_match_meta match;