diff mbox series

[nf,v2,3/7] netfilter: nf_tables: reject unbound anonymous set before commit phase

Message ID 20230612131409.63157-3-pablo@netfilter.org
State Changes Requested
Delegated to: Pablo Neira
Headers show
Series [nf,v2,1/7] netfilter: nf_tables: fix chain binding transaction logic | expand

Commit Message

Pablo Neira Ayuso June 12, 2023, 1:14 p.m. UTC
Add a new list to track set transaction and to check for unbound
anonymous sets before entering the commit phase.

Bail out at the end of the transaction handling if an anonymous set
remains unbound.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
v2: no changes

 include/net/netfilter/nf_tables.h |  2 ++
 net/netfilter/nf_tables_api.c     | 35 ++++++++++++++++++++++++++++---
 2 files changed, 34 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 9d8f57301aad..007dfa65c6c6 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -1572,6 +1572,7 @@  static inline void nft_set_elem_clear_busy(struct nft_set_ext *ext)
  */
 struct nft_trans {
 	struct list_head		list;
+	struct list_head		binding_list;
 	int				msg_type;
 	bool				put_net;
 	struct nft_ctx			ctx;
@@ -1713,6 +1714,7 @@  static inline int nft_request_module(struct net *net, const char *fmt, ...) { re
 struct nftables_pernet {
 	struct list_head	tables;
 	struct list_head	commit_list;
+	struct list_head	binding_list;
 	struct list_head	module_list;
 	struct list_head	notify_list;
 	struct mutex		commit_mutex;
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index f008fdbe83e1..92cc9141de5d 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -151,6 +151,7 @@  static struct nft_trans *nft_trans_alloc_gfp(const struct nft_ctx *ctx,
 		return NULL;
 
 	INIT_LIST_HEAD(&trans->list);
+	INIT_LIST_HEAD(&trans->binding_list);
 	trans->msg_type = msg_type;
 	trans->ctx	= *ctx;
 
@@ -163,9 +164,15 @@  static struct nft_trans *nft_trans_alloc(const struct nft_ctx *ctx,
 	return nft_trans_alloc_gfp(ctx, msg_type, size, GFP_KERNEL);
 }
 
-static void nft_trans_destroy(struct nft_trans *trans)
+static void nft_trans_list_del(struct nft_trans *trans)
 {
 	list_del(&trans->list);
+	list_del(&trans->binding_list);
+}
+
+static void nft_trans_destroy(struct nft_trans *trans)
+{
+	nft_trans_list_del(trans);
 	kfree(trans);
 }
 
@@ -330,6 +337,14 @@  static void nft_trans_commit_list_add_tail(struct net *net, struct nft_trans *tr
 {
 	struct nftables_pernet *nft_net = nft_pernet(net);
 
+	switch (trans->msg_type) {
+	case NFT_MSG_NEWSET:
+		if (!nft_trans_set_update(trans) &&
+		    nft_set_is_anonymous(nft_trans_set(trans)))
+			list_add_tail(&trans->binding_list, &nft_net->binding_list);
+		break;
+	}
+
 	list_add_tail(&trans->list, &nft_net->commit_list);
 }
 
@@ -8975,7 +8990,7 @@  static void nf_tables_trans_destroy_work(struct work_struct *w)
 	synchronize_rcu();
 
 	list_for_each_entry_safe(trans, next, &head, list) {
-		list_del(&trans->list);
+		nft_trans_list_del(trans);
 		nft_commit_release(trans);
 	}
 }
@@ -9340,6 +9355,19 @@  static int nf_tables_commit(struct net *net, struct sk_buff *skb)
 		return 0;
 	}
 
+	list_for_each_entry(trans, &nft_net->binding_list, binding_list) {
+		switch (trans->msg_type) {
+		case NFT_MSG_NEWSET:
+			if (!nft_trans_set_update(trans) &&
+			    nft_set_is_anonymous(nft_trans_set(trans)) &&
+			    !nft_trans_set_bound(trans)) {
+				pr_warn_once("nftables ruleset with unbound set\n");
+				return -EINVAL;
+			}
+			break;
+		}
+	}
+
 	/* 0. Validate ruleset, otherwise roll back for error reporting. */
 	if (nf_tables_validate(net) < 0)
 		return -EAGAIN;
@@ -9846,7 +9874,7 @@  static int __nf_tables_abort(struct net *net, enum nfnl_abort_action action)
 
 	list_for_each_entry_safe_reverse(trans, next,
 					 &nft_net->commit_list, list) {
-		list_del(&trans->list);
+		nft_trans_list_del(trans);
 		nf_tables_abort_release(trans);
 	}
 
@@ -10619,6 +10647,7 @@  static int __net_init nf_tables_init_net(struct net *net)
 
 	INIT_LIST_HEAD(&nft_net->tables);
 	INIT_LIST_HEAD(&nft_net->commit_list);
+	INIT_LIST_HEAD(&nft_net->binding_list);
 	INIT_LIST_HEAD(&nft_net->module_list);
 	INIT_LIST_HEAD(&nft_net->notify_list);
 	mutex_init(&nft_net->commit_mutex);