From 74cccc3d38438b346e40a4f8133cff3f0839ff84 Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Tue, 30 Jun 2020 19:21:11 +0200
Subject: netfilter: nf_tables: add NFTA_CHAIN_ID attribute

This netlink attribute allows you to refer to chains inside a
transaction as an alternative to the name and the handle. The chain
binding support requires this new chain ID approach.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/uapi/linux/netfilter/nf_tables.h | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'include/uapi')

diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index 4565456c0ef4..477779595b78 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -196,6 +196,7 @@ enum nft_table_attributes {
  * @NFTA_CHAIN_TYPE: type name of the string (NLA_NUL_STRING)
  * @NFTA_CHAIN_COUNTERS: counter specification of the chain (NLA_NESTED: nft_counter_attributes)
  * @NFTA_CHAIN_FLAGS: chain flags
+ * @NFTA_CHAIN_ID: uniquely identifies a chain in a transaction (NLA_U32)
  */
 enum nft_chain_attributes {
 	NFTA_CHAIN_UNSPEC,
@@ -209,6 +210,7 @@ enum nft_chain_attributes {
 	NFTA_CHAIN_COUNTERS,
 	NFTA_CHAIN_PAD,
 	NFTA_CHAIN_FLAGS,
+	NFTA_CHAIN_ID,
 	__NFTA_CHAIN_MAX
 };
 #define NFTA_CHAIN_MAX		(__NFTA_CHAIN_MAX - 1)
-- 
cgit v1.2.3


From 837830a4b439bfeb86c70b0115c280377c84714b Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Tue, 30 Jun 2020 19:21:16 +0200
Subject: netfilter: nf_tables: add NFTA_RULE_CHAIN_ID attribute

This new netlink attribute allows you to add rules to chains by the
chain ID.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/uapi/linux/netfilter/nf_tables.h |  1 +
 net/netfilter/nf_tables_api.c            | 36 ++++++++++++++++++++++++++++----
 2 files changed, 33 insertions(+), 4 deletions(-)

(limited to 'include/uapi')

diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index 477779595b78..2304d1b7ba5e 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -240,6 +240,7 @@ enum nft_rule_attributes {
 	NFTA_RULE_PAD,
 	NFTA_RULE_ID,
 	NFTA_RULE_POSITION_ID,
+	NFTA_RULE_CHAIN_ID,
 	__NFTA_RULE_MAX
 };
 #define NFTA_RULE_MAX		(__NFTA_RULE_MAX - 1)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 650ef0dd0773..fbe8f9209813 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2153,6 +2153,22 @@ err:
 	return err;
 }
 
+static struct nft_chain *nft_chain_lookup_byid(const struct net *net,
+					       const struct nlattr *nla)
+{
+	u32 id = ntohl(nla_get_be32(nla));
+	struct nft_trans *trans;
+
+	list_for_each_entry(trans, &net->nft.commit_list, list) {
+		struct nft_chain *chain = trans->ctx.chain;
+
+		if (trans->msg_type == NFT_MSG_NEWCHAIN &&
+		    id == nft_trans_chain_id(trans))
+			return chain;
+	}
+	return ERR_PTR(-ENOENT);
+}
+
 static int nf_tables_newchain(struct net *net, struct sock *nlsk,
 			      struct sk_buff *skb, const struct nlmsghdr *nlh,
 			      const struct nlattr * const nla[],
@@ -2633,6 +2649,7 @@ static const struct nla_policy nft_rule_policy[NFTA_RULE_MAX + 1] = {
 				    .len = NFT_USERDATA_MAXLEN },
 	[NFTA_RULE_ID]		= { .type = NLA_U32 },
 	[NFTA_RULE_POSITION_ID]	= { .type = NLA_U32 },
+	[NFTA_RULE_CHAIN_ID]	= { .type = NLA_U32 },
 };
 
 static int nf_tables_fill_rule_info(struct sk_buff *skb, struct net *net,
@@ -3039,10 +3056,21 @@ static int nf_tables_newrule(struct net *net, struct sock *nlsk,
 		return PTR_ERR(table);
 	}
 
-	chain = nft_chain_lookup(net, table, nla[NFTA_RULE_CHAIN], genmask);
-	if (IS_ERR(chain)) {
-		NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
-		return PTR_ERR(chain);
+	if (nla[NFTA_RULE_CHAIN]) {
+		chain = nft_chain_lookup(net, table, nla[NFTA_RULE_CHAIN],
+					 genmask);
+		if (IS_ERR(chain)) {
+			NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
+			return PTR_ERR(chain);
+		}
+	} else if (nla[NFTA_RULE_CHAIN_ID]) {
+		chain = nft_chain_lookup_byid(net, nla[NFTA_RULE_CHAIN_ID]);
+		if (IS_ERR(chain)) {
+			NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN_ID]);
+			return PTR_ERR(chain);
+		}
+	} else {
+		return -EINVAL;
 	}
 
 	if (nla[NFTA_RULE_HANDLE]) {
-- 
cgit v1.2.3


From 51d70f181ff4e2c996ddf256af1efecd7d5864e5 Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Tue, 30 Jun 2020 19:21:21 +0200
Subject: netfilter: nf_tables: add NFTA_VERDICT_CHAIN_ID attribute

This netlink attribute allows you to identify the chain to jump/goto by
means of the chain ID.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/uapi/linux/netfilter/nf_tables.h |  2 ++
 net/netfilter/nf_tables_api.c            | 16 +++++++++++++---
 2 files changed, 15 insertions(+), 3 deletions(-)

(limited to 'include/uapi')

diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index 2304d1b7ba5e..683e75126d68 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -471,11 +471,13 @@ enum nft_data_attributes {
  *
  * @NFTA_VERDICT_CODE: nf_tables verdict (NLA_U32: enum nft_verdicts)
  * @NFTA_VERDICT_CHAIN: jump target chain name (NLA_STRING)
+ * @NFTA_VERDICT_CHAIN_ID: jump target chain ID (NLA_U32)
  */
 enum nft_verdict_attributes {
 	NFTA_VERDICT_UNSPEC,
 	NFTA_VERDICT_CODE,
 	NFTA_VERDICT_CHAIN,
+	NFTA_VERDICT_CHAIN_ID,
 	__NFTA_VERDICT_MAX
 };
 #define NFTA_VERDICT_MAX	(__NFTA_VERDICT_MAX - 1)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index fbe8f9209813..d86602797a69 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -8242,6 +8242,7 @@ static const struct nla_policy nft_verdict_policy[NFTA_VERDICT_MAX + 1] = {
 	[NFTA_VERDICT_CODE]	= { .type = NLA_U32 },
 	[NFTA_VERDICT_CHAIN]	= { .type = NLA_STRING,
 				    .len = NFT_CHAIN_MAXNAMELEN - 1 },
+	[NFTA_VERDICT_CHAIN_ID]	= { .type = NLA_U32 },
 };
 
 static int nft_verdict_init(const struct nft_ctx *ctx, struct nft_data *data,
@@ -8278,10 +8279,19 @@ static int nft_verdict_init(const struct nft_ctx *ctx, struct nft_data *data,
 		break;
 	case NFT_JUMP:
 	case NFT_GOTO:
-		if (!tb[NFTA_VERDICT_CHAIN])
+		if (tb[NFTA_VERDICT_CHAIN]) {
+			chain = nft_chain_lookup(ctx->net, ctx->table,
+						 tb[NFTA_VERDICT_CHAIN],
+						 genmask);
+		} else if (tb[NFTA_VERDICT_CHAIN_ID]) {
+			chain = nft_chain_lookup_byid(ctx->net,
+						      tb[NFTA_VERDICT_CHAIN_ID]);
+			if (IS_ERR(chain))
+				return PTR_ERR(chain);
+		} else {
 			return -EINVAL;
-		chain = nft_chain_lookup(ctx->net, ctx->table,
-					 tb[NFTA_VERDICT_CHAIN], genmask);
+		}
+
 		if (IS_ERR(chain))
 			return PTR_ERR(chain);
 		if (nft_is_base_chain(chain))
-- 
cgit v1.2.3


From 67c49de4ad862c567088c5119cf125e566f56e7f Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Tue, 30 Jun 2020 19:21:25 +0200
Subject: netfilter: nf_tables: expose enum nft_chain_flags through UAPI

This enum definition was never exposed through UAPI. Rename
NFT_BASE_CHAIN to NFT_CHAIN_BASE for consistency.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/net/netfilter/nf_tables.h        | 7 +------
 include/uapi/linux/netfilter/nf_tables.h | 5 +++++
 net/netfilter/nf_tables_api.c            | 4 ++--
 3 files changed, 8 insertions(+), 8 deletions(-)

(limited to 'include/uapi')

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 3e5226684017..6d1e7da6e00a 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -921,11 +921,6 @@ static inline void nft_set_elem_update_expr(const struct nft_set_ext *ext,
 	     (expr) != (last); \
 	     (expr) = nft_expr_next(expr))
 
-enum nft_chain_flags {
-	NFT_BASE_CHAIN			= 0x1,
-	NFT_CHAIN_HW_OFFLOAD		= 0x2,
-};
-
 #define NFT_CHAIN_POLICY_UNSET		U8_MAX
 
 /**
@@ -1036,7 +1031,7 @@ static inline struct nft_base_chain *nft_base_chain(const struct nft_chain *chai
 
 static inline bool nft_is_base_chain(const struct nft_chain *chain)
 {
-	return chain->flags & NFT_BASE_CHAIN;
+	return chain->flags & NFT_CHAIN_BASE;
 }
 
 int __nft_release_basechain(struct nft_ctx *ctx);
diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index 683e75126d68..2cf7cc3b50c1 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -184,6 +184,11 @@ enum nft_table_attributes {
 };
 #define NFTA_TABLE_MAX		(__NFTA_TABLE_MAX - 1)
 
+enum nft_chain_flags {
+	NFT_CHAIN_BASE		= (1 << 0),
+	NFT_CHAIN_HW_OFFLOAD	= (1 << 1),
+};
+
 /**
  * enum nft_chain_attributes - nf_tables chain netlink attributes
  *
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index d86602797a69..b7582a1c8dce 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1903,7 +1903,7 @@ static int nft_basechain_init(struct nft_base_chain *basechain, u8 family,
 		nft_basechain_hook_init(&basechain->ops, family, hook, chain);
 	}
 
-	chain->flags |= NFT_BASE_CHAIN | flags;
+	chain->flags |= NFT_CHAIN_BASE | flags;
 	basechain->policy = NF_ACCEPT;
 	if (chain->flags & NFT_CHAIN_HW_OFFLOAD &&
 	    nft_chain_offload_priority(basechain) < 0)
@@ -2255,7 +2255,7 @@ static int nf_tables_newchain(struct net *net, struct sock *nlsk,
 		if (nlh->nlmsg_flags & NLM_F_REPLACE)
 			return -EOPNOTSUPP;
 
-		flags |= chain->flags & NFT_BASE_CHAIN;
+		flags |= chain->flags & NFT_CHAIN_BASE;
 		return nf_tables_updchain(&ctx, genmask, policy, flags);
 	}
 
-- 
cgit v1.2.3


From d0e2c7de92c7f2b3d355ad76b0bb9fc43d1beb87 Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Tue, 30 Jun 2020 19:21:36 +0200
Subject: netfilter: nf_tables: add NFT_CHAIN_BINDING

This new chain flag specifies that:

* the kernel dynamically allocates the chain name, if no chain name
  is specified.

* If the immediate expression that refers to this chain is removed,
  then this bound chain (and its content) is destroyed.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/net/netfilter/nf_tables.h        | 13 ++++-
 include/uapi/linux/netfilter/nf_tables.h |  1 +
 net/netfilter/nf_tables_api.c            | 86 +++++++++++++++++++++++++++-----
 net/netfilter/nft_immediate.c            | 51 +++++++++++++++++++
 4 files changed, 138 insertions(+), 13 deletions(-)

(limited to 'include/uapi')

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 6d1e7da6e00a..822c26766330 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -899,6 +899,8 @@ static inline struct nft_userdata *nft_userdata(const struct nft_rule *rule)
 	return (void *)&rule->data[rule->dlen];
 }
 
+void nf_tables_rule_release(const struct nft_ctx *ctx, struct nft_rule *rule);
+
 static inline void nft_set_elem_update_expr(const struct nft_set_ext *ext,
 					    struct nft_regs *regs,
 					    const struct nft_pktinfo *pkt)
@@ -944,7 +946,8 @@ struct nft_chain {
 	struct nft_table		*table;
 	u64				handle;
 	u32				use;
-	u8				flags:6,
+	u8				flags:5,
+					bound:1,
 					genmask:2;
 	char				*name;
 
@@ -989,6 +992,14 @@ int nft_chain_validate_dependency(const struct nft_chain *chain,
 int nft_chain_validate_hooks(const struct nft_chain *chain,
                              unsigned int hook_flags);
 
+static inline bool nft_chain_is_bound(struct nft_chain *chain)
+{
+	return (chain->flags & NFT_CHAIN_BINDING) && chain->bound;
+}
+
+void nft_chain_del(struct nft_chain *chain);
+void nf_tables_chain_destroy(struct nft_ctx *ctx);
+
 struct nft_stats {
 	u64			bytes;
 	u64			pkts;
diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index 2cf7cc3b50c1..e00b4ae6174e 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -187,6 +187,7 @@ enum nft_table_attributes {
 enum nft_chain_flags {
 	NFT_CHAIN_BASE		= (1 << 0),
 	NFT_CHAIN_HW_OFFLOAD	= (1 << 1),
+	NFT_CHAIN_BINDING	= (1 << 2),
 };
 
 /**
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index a7cb9c07802b..b8a970dad213 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1056,6 +1056,9 @@ static int nft_flush_table(struct nft_ctx *ctx)
 		if (!nft_is_active_next(ctx->net, chain))
 			continue;
 
+		if (nft_chain_is_bound(chain))
+			continue;
+
 		ctx->chain = chain;
 
 		err = nft_delrule_by_chain(ctx);
@@ -1098,6 +1101,9 @@ static int nft_flush_table(struct nft_ctx *ctx)
 		if (!nft_is_active_next(ctx->net, chain))
 			continue;
 
+		if (nft_chain_is_bound(chain))
+			continue;
+
 		ctx->chain = chain;
 
 		err = nft_delchain(ctx);
@@ -1413,13 +1419,12 @@ static int nf_tables_fill_chain_info(struct sk_buff *skb, struct net *net,
 					      lockdep_commit_lock_is_held(net));
 		if (nft_dump_stats(skb, stats))
 			goto nla_put_failure;
-
-		if ((chain->flags & NFT_CHAIN_HW_OFFLOAD) &&
-		    nla_put_be32(skb, NFTA_CHAIN_FLAGS,
-				 htonl(NFT_CHAIN_HW_OFFLOAD)))
-			goto nla_put_failure;
 	}
 
+	if (chain->flags &&
+	    nla_put_be32(skb, NFTA_CHAIN_FLAGS, htonl(chain->flags)))
+		goto nla_put_failure;
+
 	if (nla_put_be32(skb, NFTA_CHAIN_USE, htonl(chain->use)))
 		goto nla_put_failure;
 
@@ -1621,7 +1626,7 @@ static void nf_tables_chain_free_chain_rules(struct nft_chain *chain)
 	kvfree(chain->rules_next);
 }
 
-static void nf_tables_chain_destroy(struct nft_ctx *ctx)
+void nf_tables_chain_destroy(struct nft_ctx *ctx)
 {
 	struct nft_chain *chain = ctx->chain;
 	struct nft_hook *hook, *next;
@@ -1928,6 +1933,8 @@ static int nft_chain_add(struct nft_table *table, struct nft_chain *chain)
 	return 0;
 }
 
+static u64 chain_id;
+
 static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
 			      u8 policy, u32 flags)
 {
@@ -1936,6 +1943,7 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
 	struct nft_base_chain *basechain;
 	struct nft_stats __percpu *stats;
 	struct net *net = ctx->net;
+	char name[NFT_NAME_MAXLEN];
 	struct nft_trans *trans;
 	struct nft_chain *chain;
 	struct nft_rule **rules;
@@ -1947,6 +1955,9 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
 	if (nla[NFTA_CHAIN_HOOK]) {
 		struct nft_chain_hook hook;
 
+		if (flags & NFT_CHAIN_BINDING)
+			return -EOPNOTSUPP;
+
 		err = nft_chain_parse_hook(net, nla, &hook, family, true);
 		if (err < 0)
 			return err;
@@ -1976,16 +1987,33 @@ static int nf_tables_addchain(struct nft_ctx *ctx, u8 family, u8 genmask,
 			return err;
 		}
 	} else {
+		if (flags & NFT_CHAIN_BASE)
+			return -EINVAL;
+		if (flags & NFT_CHAIN_HW_OFFLOAD)
+			return -EOPNOTSUPP;
+
 		chain = kzalloc(sizeof(*chain), GFP_KERNEL);
 		if (chain == NULL)
 			return -ENOMEM;
+
+		chain->flags = flags;
 	}
 	ctx->chain = chain;
 
 	INIT_LIST_HEAD(&chain->rules);
 	chain->handle = nf_tables_alloc_handle(table);
 	chain->table = table;
-	chain->name = nla_strdup(nla[NFTA_CHAIN_NAME], GFP_KERNEL);
+
+	if (nla[NFTA_CHAIN_NAME]) {
+		chain->name = nla_strdup(nla[NFTA_CHAIN_NAME], GFP_KERNEL);
+	} else {
+		if (!(flags & NFT_CHAIN_BINDING))
+			return -EINVAL;
+
+		snprintf(name, sizeof(name), "__chain%llu", ++chain_id);
+		chain->name = kstrdup(name, GFP_KERNEL);
+	}
+
 	if (!chain->name) {
 		err = -ENOMEM;
 		goto err1;
@@ -2976,8 +3004,7 @@ static void nf_tables_rule_destroy(const struct nft_ctx *ctx,
 	kfree(rule);
 }
 
-static void nf_tables_rule_release(const struct nft_ctx *ctx,
-				   struct nft_rule *rule)
+void nf_tables_rule_release(const struct nft_ctx *ctx, struct nft_rule *rule)
 {
 	nft_rule_expr_deactivate(ctx, rule, NFT_TRANS_RELEASE);
 	nf_tables_rule_destroy(ctx, rule);
@@ -3075,6 +3102,9 @@ static int nf_tables_newrule(struct net *net, struct sock *nlsk,
 			NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
 			return PTR_ERR(chain);
 		}
+		if (nft_chain_is_bound(chain))
+			return -EOPNOTSUPP;
+
 	} else if (nla[NFTA_RULE_CHAIN_ID]) {
 		chain = nft_chain_lookup_byid(net, nla[NFTA_RULE_CHAIN_ID]);
 		if (IS_ERR(chain)) {
@@ -3294,6 +3324,8 @@ static int nf_tables_delrule(struct net *net, struct sock *nlsk,
 			NL_SET_BAD_ATTR(extack, nla[NFTA_RULE_CHAIN]);
 			return PTR_ERR(chain);
 		}
+		if (nft_chain_is_bound(chain))
+			return -EOPNOTSUPP;
 	}
 
 	nft_ctx_init(&ctx, net, skb, nlh, family, table, chain, nla);
@@ -5330,11 +5362,24 @@ static int nf_tables_newsetelem(struct net *net, struct sock *nlsk,
  */
 void nft_data_hold(const struct nft_data *data, enum nft_data_types type)
 {
+	struct nft_chain *chain;
+	struct nft_rule *rule;
+
 	if (type == NFT_DATA_VERDICT) {
 		switch (data->verdict.code) {
 		case NFT_JUMP:
 		case NFT_GOTO:
-			data->verdict.chain->use++;
+			chain = data->verdict.chain;
+			chain->use++;
+
+			if (!nft_chain_is_bound(chain))
+				break;
+
+			chain->table->use++;
+			list_for_each_entry(rule, &chain->rules, list)
+				chain->use++;
+
+			nft_chain_add(chain->table, chain);
 			break;
 		}
 	}
@@ -7474,7 +7519,7 @@ static void nft_obj_del(struct nft_object *obj)
 	list_del_rcu(&obj->list);
 }
 
-static void nft_chain_del(struct nft_chain *chain)
+void nft_chain_del(struct nft_chain *chain)
 {
 	struct nft_table *table = chain->table;
 
@@ -7825,6 +7870,10 @@ static int __nf_tables_abort(struct net *net, bool autoload)
 				kfree(nft_trans_chain_name(trans));
 				nft_trans_destroy(trans);
 			} else {
+				if (nft_chain_is_bound(trans->ctx.chain)) {
+					nft_trans_destroy(trans);
+					break;
+				}
 				trans->ctx.table->use--;
 				nft_chain_del(trans->ctx.chain);
 				nf_tables_unregister_hook(trans->ctx.net,
@@ -8321,10 +8370,23 @@ static int nft_verdict_init(const struct nft_ctx *ctx, struct nft_data *data,
 
 static void nft_verdict_uninit(const struct nft_data *data)
 {
+	struct nft_chain *chain;
+	struct nft_rule *rule;
+
 	switch (data->verdict.code) {
 	case NFT_JUMP:
 	case NFT_GOTO:
-		data->verdict.chain->use--;
+		chain = data->verdict.chain;
+		chain->use--;
+
+		if (!nft_chain_is_bound(chain))
+			break;
+
+		chain->table->use--;
+		list_for_each_entry(rule, &chain->rules, list)
+			chain->use--;
+
+		nft_chain_del(chain);
 		break;
 	}
 }
diff --git a/net/netfilter/nft_immediate.c b/net/netfilter/nft_immediate.c
index c7f0ef73d939..9e556638bb32 100644
--- a/net/netfilter/nft_immediate.c
+++ b/net/netfilter/nft_immediate.c
@@ -54,6 +54,23 @@ static int nft_immediate_init(const struct nft_ctx *ctx,
 	if (err < 0)
 		goto err1;
 
+	if (priv->dreg == NFT_REG_VERDICT) {
+		struct nft_chain *chain = priv->data.verdict.chain;
+
+		switch (priv->data.verdict.code) {
+		case NFT_JUMP:
+		case NFT_GOTO:
+			if (nft_chain_is_bound(chain)) {
+				err = -EBUSY;
+				goto err1;
+			}
+			chain->bound = true;
+			break;
+		default:
+			break;
+		}
+	}
+
 	return 0;
 
 err1:
@@ -81,6 +98,39 @@ static void nft_immediate_deactivate(const struct nft_ctx *ctx,
 	return nft_data_release(&priv->data, nft_dreg_to_type(priv->dreg));
 }
 
+static void nft_immediate_destroy(const struct nft_ctx *ctx,
+				  const struct nft_expr *expr)
+{
+	const struct nft_immediate_expr *priv = nft_expr_priv(expr);
+	const struct nft_data *data = &priv->data;
+	struct nft_ctx chain_ctx;
+	struct nft_chain *chain;
+	struct nft_rule *rule;
+
+	if (priv->dreg != NFT_REG_VERDICT)
+		return;
+
+	switch (data->verdict.code) {
+	case NFT_JUMP:
+	case NFT_GOTO:
+		chain = data->verdict.chain;
+
+		if (!nft_chain_is_bound(chain))
+			break;
+
+		chain_ctx = *ctx;
+		chain_ctx.chain = chain;
+
+		list_for_each_entry(rule, &chain->rules, list)
+			nf_tables_rule_release(&chain_ctx, rule);
+
+		nf_tables_chain_destroy(&chain_ctx);
+		break;
+	default:
+		break;
+	}
+}
+
 static int nft_immediate_dump(struct sk_buff *skb, const struct nft_expr *expr)
 {
 	const struct nft_immediate_expr *priv = nft_expr_priv(expr);
@@ -170,6 +220,7 @@ static const struct nft_expr_ops nft_imm_ops = {
 	.init		= nft_immediate_init,
 	.activate	= nft_immediate_activate,
 	.deactivate	= nft_immediate_deactivate,
+	.destroy	= nft_immediate_destroy,
 	.dump		= nft_immediate_dump,
 	.validate	= nft_immediate_validate,
 	.offload	= nft_immediate_offload,
-- 
cgit v1.2.3


From c1f79a2eefdcc0aef5d7a911c27a3f75f1936ecd Mon Sep 17 00:00:00 2001
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Sat, 4 Jul 2020 02:51:28 +0200
Subject: netfilter: nf_tables: reject unsupported chain flags

Bail out if userspace sends unsupported chain flags.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 include/uapi/linux/netfilter/nf_tables.h | 3 +++
 net/netfilter/nf_tables_api.c            | 3 +++
 2 files changed, 6 insertions(+)

(limited to 'include/uapi')

diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index e00b4ae6174e..42f351c1f5c5 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -189,6 +189,9 @@ enum nft_chain_flags {
 	NFT_CHAIN_HW_OFFLOAD	= (1 << 1),
 	NFT_CHAIN_BINDING	= (1 << 2),
 };
+#define NFT_CHAIN_FLAGS		(NFT_CHAIN_BASE		| \
+				 NFT_CHAIN_HW_OFFLOAD	| \
+				 NFT_CHAIN_BINDING)
 
 /**
  * enum nft_chain_attributes - nf_tables chain netlink attributes
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index b8a970dad213..f96785586f64 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2285,6 +2285,9 @@ static int nf_tables_newchain(struct net *net, struct sock *nlsk,
 	else if (chain)
 		flags = chain->flags;
 
+	if (flags & ~NFT_CHAIN_FLAGS)
+		return -EOPNOTSUPP;
+
 	nft_ctx_init(&ctx, net, skb, nlh, family, table, chain, nla);
 
 	if (chain != NULL) {
-- 
cgit v1.2.3