netfilter: nf_tables: check if catch-all set element is active in next generation

When deactivating the catch-all set element, check the state in the next
generation that represents this transaction.

This bug uncovered after the recent removal of the element busy mark
a2dd023 ("netfilter: nf_tables: remove busy mark and gc batch API").

Fixes: aaa3104 ("netfilter: nftables: add catch-all set element support")
Cc: stable@vger.kernel.org
Reported-by: lonial con <kongln9170@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Author: ummakynes

net/netfilter/nf_tables_api.c

@@ -6578,7 +6578,7 @@ static int nft_setelem_catchall_deactivate(const struct net *net,
 
 	list_for_each_entry(catchall, &set->catchall_list, list) {
 		ext = nft_set_elem_ext(set, catchall->elem);
-		if (!nft_is_active(net, ext))
+		if (!nft_is_active_next(net, ext))
 			continue;
 
 		kfree(elem->priv);