[PATCH nf-next v3] netfilter: nf_table_offload: Fix the incorrect rcu usage in nft_indr_block_cb

[wenxu]

From: wenxu <we...@ucloud.cn>

The flow_block_ing_cmd() needs to call blocking functions while iterating
block_ing_cb_list, nft_indr_block_cb is in the cb_list,
So it is the incorrect rcu case. To fix it just traverse the list under
the commit mutex.

Fixes: 9a32669fecfb ("netfilter: nf_tables_offload: support indr block call")
Signed-off-by: wenxu <we...@ucloud.cn>
---
v3: rebase to patches 1156728 and 1156729

 net/netfilter/nf_tables_offload.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/net/netfilter/nf_tables_offload.c 
b/net/netfilter/nf_tables_offload.c
index 113ac40..ca9e0cb 100644
--- a/net/netfilter/nf_tables_offload.c
+++ b/net/netfilter/nf_tables_offload.c
@@ -357,11 +357,12 @@ static void nft_indr_block_cb(struct net_device *dev,
        const struct nft_table *table;
        const struct nft_chain *chain;
 
-       list_for_each_entry_rcu(table, &net->nft.tables, list) {
+       mutex_lock(&net->nft.commit_mutex);
+       list_for_each_entry(table, &net->nft.tables, list) {
                if (table->family != NFPROTO_NETDEV)
                        continue;
 
-               list_for_each_entry_rcu(chain, &table->chains, list) {
+               list_for_each_entry(chain, &table->chains, list) {
                        if (!nft_is_base_chain(chain))
                                continue;
 
@@ -370,9 +371,11 @@ static void nft_indr_block_cb(struct net_device *dev,
                                continue;
 
                        nft_indr_block_ing_cmd(dev, basechain, cb, cb_priv, 
cmd);
+                       mutex_unlock(&net->nft.commit_mutex);
                        return;
                }
        }
+       mutex_unlock(&net->nft.commit_mutex);
 }
 
 static struct flow_indr_block_ing_entry block_ing_entry = {
-- 
1.8.3.1