[PATCH net-next 2/3] net: ethernet: mtk_eth_soc: missing mutex

[Pablo Neira Ayuso]

Patch 2ed37183abb7 ("netfilter: flowtable: separate replace, destroy and
stats to different workqueues") splits the workqueue per event type. Add
a mutex to serialize updates.

Fixes: 502e84e2382d ("net: ethernet: mtk_eth_soc: add flow offloading support")
Reported-by: Frank Wunderlich <fran...@public-files.de>
Signed-off-by: Pablo Neira Ayuso <pa...@netfilter.org>
---
 .../net/ethernet/mediatek/mtk_ppe_offload.c   | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_ppe_offload.c 
b/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
index 4975106fbc42..2759c875c791 100644
--- a/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
+++ b/drivers/net/ethernet/mediatek/mtk_ppe_offload.c
@@ -391,6 +391,8 @@ mtk_flow_offload_stats(struct mtk_eth *eth, struct 
flow_cls_offload *f)
        return 0;
 }
 
+static DEFINE_MUTEX(mtk_flow_offload_mutex);
+
 static int
 mtk_eth_setup_tc_block_cb(enum tc_setup_type type, void *type_data, void 
*cb_priv)
 {
@@ -398,6 +400,7 @@ mtk_eth_setup_tc_block_cb(enum tc_setup_type type, void 
*type_data, void *cb_pri
        struct net_device *dev = cb_priv;
        struct mtk_mac *mac = netdev_priv(dev);
        struct mtk_eth *eth = mac->hw;
+       int err;
 
        if (!tc_can_offload(dev))
                return -EOPNOTSUPP;
@@ -405,18 +408,24 @@ mtk_eth_setup_tc_block_cb(enum tc_setup_type type, void 
*type_data, void *cb_pri
        if (type != TC_SETUP_CLSFLOWER)
                return -EOPNOTSUPP;
 
+       mutex_lock(&mtk_flow_offload_mutex);
        switch (cls->command) {
        case FLOW_CLS_REPLACE:
-               return mtk_flow_offload_replace(eth, cls);
+               err = mtk_flow_offload_replace(eth, cls);
+               break;
        case FLOW_CLS_DESTROY:
-               return mtk_flow_offload_destroy(eth, cls);
+               err = mtk_flow_offload_destroy(eth, cls);
+               break;
        case FLOW_CLS_STATS:
-               return mtk_flow_offload_stats(eth, cls);
+               err = mtk_flow_offload_stats(eth, cls);
+               break;
        default:
-               return -EOPNOTSUPP;
+               err = -EOPNOTSUPP;
+               break;
        }
+       mutex_unlock(&mtk_flow_offload_mutex);
 
-       return 0;
+       return err;
 }
 
 static int
-- 
2.20.1