netfilter: nf_tables: use rcu chain hook list iterator from netlink dump path

Lockless iteration over hook list is possible from netlink dump path,
use rcu variant to iterate over the hook list as is done with flowtable
hooks.

Fixes: b9703ed44ffb ("netfilter: nf_tables: support for adding new devices to an existing netdev chain")
Reported-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 042080aeb46c105b655266e87a9e34a7edb485cf..8f073e6c772a5f134c8d1c35c3d0edc69b43be23 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1849,7 +1849,7 @@ static int nft_dump_basechain_hook(struct sk_buff *skb, int family,
                if (!hook_list)
                        hook_list = &basechain->hook_list;
 
-               list_for_each_entry(hook, hook_list, list) {
+               list_for_each_entry_rcu(hook, hook_list, list) {
                        if (!first)
                                first = hook;