netfilter: nf_tables: Flowtable hook's pf value never varies

When checking for duplicate hooks in nft_register_flowtable_net_hooks(),
comparing ops.pf value is pointless as it is always NFPROTO_NETDEV with
flowtable hooks.

Dropping the check leaves the search identical to the one in
nft_hook_list_find() so call that function instead of open coding.

Signed-off-by: Phil Sutter <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>

Author: Phil Sutter

net/netfilter/nf_tables_api.c

@@ -8895,7 +8895,7 @@ static int nft_register_flowtable_net_hooks(struct net *net,
 					    struct list_head *hook_list,
 					    struct nft_flowtable *flowtable)
 {
-	struct nft_hook *hook, *hook2, *next;
+	struct nft_hook *hook, *next;
 	struct nft_flowtable *ft;
 	int err, i = 0;
 
@@ -8904,12 +8904,9 @@ static int nft_register_flowtable_net_hooks(struct net *net,
 			if (!nft_is_active_next(net, ft))
 				continue;
 
-			list_for_each_entry(hook2, &ft->hook_list, list) {
-				if (hook->ops.dev == hook2->ops.dev &&
-				    hook->ops.pf == hook2->ops.pf) {
-					err = -EEXIST;
-					goto err_unregister_net_hooks;
-				}
+			if (nft_hook_list_find(&ft->hook_list, hook)) {
+				err = -EEXIST;
+				goto err_unregister_net_hooks;
 			}
 		}