netfilter: nf_tables: Carry reset boolean in nft_set_dump_ctx

Relieve the dump callback from having to check nlmsg_type upon each
call. Prep work for set element reset locking.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nf_tables_api.c

@@ -5715,6 +5715,7 @@ static void audit_log_nft_set_reset(const struct nft_table *table,
 struct nft_set_dump_ctx {
 	const struct nft_set	*set;
 	struct nft_ctx		ctx;
+	bool			reset;
 };
 
 static int nft_set_catchall_dump(struct net *net, struct sk_buff *skb,
@@ -5752,7 +5753,6 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb)
 	bool set_found = false;
 	struct nlmsghdr *nlh;
 	struct nlattr *nest;
-	bool reset = false;
 	u32 portid, seq;
 	int event;
 
@@ -5800,12 +5800,9 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb)
 	if (nest == NULL)
 		goto nla_put_failure;
 
-	if (NFNL_MSG_TYPE(cb->nlh->nlmsg_type) == NFT_MSG_GETSETELEM_RESET)
-		reset = true;
-
 	args.cb			= cb;
 	args.skb		= skb;
-	args.reset		= reset;
+	args.reset		= dump_ctx->reset;
 	args.iter.genmask	= nft_genmask_cur(net);
 	args.iter.skip		= cb->args[0];
 	args.iter.count		= 0;
@@ -5815,11 +5812,11 @@ static int nf_tables_dump_set(struct sk_buff *skb, struct netlink_callback *cb)
 
 	if (!args.iter.err && args.iter.count == cb->args[0])
 		args.iter.err = nft_set_catchall_dump(net, skb, set,
-						      reset, cb->seq);
+						      dump_ctx->reset, cb->seq);
 	nla_nest_end(skb, nest);
 	nlmsg_end(skb, nlh);
 
-	if (reset && args.iter.count > args.iter.skip)
+	if (dump_ctx->reset && args.iter.count > args.iter.skip)
 		audit_log_nft_set_reset(table, cb->seq,
 					args.iter.count - args.iter.skip);
 
@@ -6072,6 +6069,9 @@ static int nf_tables_getsetelem(struct sk_buff *skb,
 
 	nft_ctx_init(&ctx, net, skb, info->nlh, family, table, NULL, nla);
 
+	if (NFNL_MSG_TYPE(info->nlh->nlmsg_type) == NFT_MSG_GETSETELEM_RESET)
+		reset = true;
+
 	if (info->nlh->nlmsg_flags & NLM_F_DUMP) {
 		struct netlink_dump_control c = {
 			.start = nf_tables_dump_set_start,
@@ -6082,6 +6082,7 @@ static int nf_tables_getsetelem(struct sk_buff *skb,
 		struct nft_set_dump_ctx dump_ctx = {
 			.set = set,
 			.ctx = ctx,
+			.reset = reset,
 		};
 
 		c.data = &dump_ctx;
@@ -6091,9 +6092,6 @@ static int nf_tables_getsetelem(struct sk_buff *skb,
 	if (!nla[NFTA_SET_ELEM_LIST_ELEMENTS])
 		return -EINVAL;
 
-	if (NFNL_MSG_TYPE(info->nlh->nlmsg_type) == NFT_MSG_GETSETELEM_RESET)
-		reset = true;
-
 	nla_for_each_nested(attr, nla[NFTA_SET_ELEM_LIST_ELEMENTS], rem) {
 		err = nft_get_set_elem(&ctx, set, attr, reset);
 		if (err < 0) {