netfilter: nftables: add nft_parse_register_load() and use it

[ Upstream commit 4f16d25 ]

This new function combines the netlink register attribute parser
and the load validation function.

This update requires to replace:

	enum nft_registers      sreg:8;

in many of the expression private areas otherwise compiler complains
with:

	error: cannot take address of bit-field ‘sreg’

when passing the register field as reference.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

include/net/netfilter/nf_tables.h

@@ -203,7 +203,7 @@ int nft_parse_u32_check(const struct nlattr *attr, int max, u32 *dest);
 unsigned int nft_parse_register(const struct nlattr *attr);
 int nft_dump_register(struct sk_buff *skb, unsigned int attr, unsigned int reg);
 
-int nft_validate_register_load(enum nft_registers reg, unsigned int len);
+int nft_parse_register_load(const struct nlattr *attr, u8 *sreg, u32 len);
 int nft_validate_register_store(const struct nft_ctx *ctx,
 				enum nft_registers reg,
 				const struct nft_data *data,

include/net/netfilter/nf_tables_core.h

@@ -26,14 +26,14 @@ void nf_tables_core_module_exit(void);
 struct nft_bitwise_fast_expr {
 	u32			mask;
 	u32			xor;
-	enum nft_registers	sreg:8;
+	u8			sreg;
 	enum nft_registers	dreg:8;
 };
 
 struct nft_cmp_fast_expr {
 	u32			data;
 	u32			mask;
-	enum nft_registers	sreg:8;
+	u8			sreg;
 	u8			len;
 	bool			inv;
 };
@@ -67,7 +67,7 @@ struct nft_payload_set {
 	enum nft_payload_bases	base:8;
 	u8			offset;
 	u8			len;
-	enum nft_registers	sreg:8;
+	u8			sreg;
 	u8			csum_type;
 	u8			csum_offset;
 	u8			csum_flags;

include/net/netfilter/nft_meta.h

@@ -8,7 +8,7 @@ struct nft_meta {
 	enum nft_meta_keys	key:8;
 	union {
 		enum nft_registers	dreg:8;
-		enum nft_registers	sreg:8;
+		u8		sreg;
 	};
 };
 

net/ipv4/netfilter/nft_dup_ipv4.c

@@ -13,8 +13,8 @@
 #include <net/netfilter/ipv4/nf_dup_ipv4.h>
 
 struct nft_dup_ipv4 {
-	enum nft_registers	sreg_addr:8;
-	enum nft_registers	sreg_dev:8;
+	u8	sreg_addr;
+	u8	sreg_dev;
 };
 
 static void nft_dup_ipv4_eval(const struct nft_expr *expr,
@@ -40,16 +40,16 @@ static int nft_dup_ipv4_init(const struct nft_ctx *ctx,
 	if (tb[NFTA_DUP_SREG_ADDR] == NULL)
 		return -EINVAL;
 
-	priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]);
-	err = nft_validate_register_load(priv->sreg_addr, sizeof(struct in_addr));
+	err = nft_parse_register_load(tb[NFTA_DUP_SREG_ADDR], &priv->sreg_addr,
+				      sizeof(struct in_addr));
 	if (err < 0)
 		return err;
 
-	if (tb[NFTA_DUP_SREG_DEV] != NULL) {
-		priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]);
-		return nft_validate_register_load(priv->sreg_dev, sizeof(int));
-	}
-	return 0;
+	if (tb[NFTA_DUP_SREG_DEV])
+		err = nft_parse_register_load(tb[NFTA_DUP_SREG_DEV],
+					      &priv->sreg_dev, sizeof(int));
+
+	return err;
 }
 
 static int nft_dup_ipv4_dump(struct sk_buff *skb, const struct nft_expr *expr)

net/ipv6/netfilter/nft_dup_ipv6.c

@@ -13,8 +13,8 @@
 #include <net/netfilter/ipv6/nf_dup_ipv6.h>
 
 struct nft_dup_ipv6 {
-	enum nft_registers	sreg_addr:8;
-	enum nft_registers	sreg_dev:8;
+	u8	sreg_addr;
+	u8	sreg_dev;
 };
 
 static void nft_dup_ipv6_eval(const struct nft_expr *expr,
@@ -38,16 +38,16 @@ static int nft_dup_ipv6_init(const struct nft_ctx *ctx,
 	if (tb[NFTA_DUP_SREG_ADDR] == NULL)
 		return -EINVAL;
 
-	priv->sreg_addr = nft_parse_register(tb[NFTA_DUP_SREG_ADDR]);
-	err = nft_validate_register_load(priv->sreg_addr, sizeof(struct in6_addr));
+	err = nft_parse_register_load(tb[NFTA_DUP_SREG_ADDR], &priv->sreg_addr,
+				      sizeof(struct in6_addr));
 	if (err < 0)
 		return err;
 
-	if (tb[NFTA_DUP_SREG_DEV] != NULL) {
-		priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]);
-		return nft_validate_register_load(priv->sreg_dev, sizeof(int));
-	}
-	return 0;
+	if (tb[NFTA_DUP_SREG_DEV])
+		err = nft_parse_register_load(tb[NFTA_DUP_SREG_DEV],
+					      &priv->sreg_dev, sizeof(int));
+
+	return err;
 }
 
 static int nft_dup_ipv6_dump(struct sk_buff *skb, const struct nft_expr *expr)

net/netfilter/nf_tables_api.c

@@ -8514,7 +8514,7 @@ EXPORT_SYMBOL_GPL(nft_dump_register);
  * 	Validate that the input register is one of the general purpose
  * 	registers and that the length of the load is within the bounds.
  */
-int nft_validate_register_load(enum nft_registers reg, unsigned int len)
+static int nft_validate_register_load(enum nft_registers reg, unsigned int len)
 {
 	if (reg < NFT_REG_1 * NFT_REG_SIZE / NFT_REG32_SIZE)
 		return -EINVAL;
@@ -8525,7 +8525,21 @@ int nft_validate_register_load(enum nft_registers reg, unsigned int len)
 
 	return 0;
 }
-EXPORT_SYMBOL_GPL(nft_validate_register_load);
+
+int nft_parse_register_load(const struct nlattr *attr, u8 *sreg, u32 len)
+{
+	u32 reg;
+	int err;
+
+	reg = nft_parse_register(attr);
+	err = nft_validate_register_load(reg, len);
+	if (err < 0)
+		return err;
+
+	*sreg = reg;
+	return 0;
+}
+EXPORT_SYMBOL_GPL(nft_parse_register_load);
 
 /**
  *	nft_validate_register_store - validate an expressions' register store

net/netfilter/nft_bitwise.c

@@ -16,7 +16,7 @@
 #include <net/netfilter/nf_tables_offload.h>
 
 struct nft_bitwise {
-	enum nft_registers	sreg:8;
+	u8			sreg;
 	enum nft_registers	dreg:8;
 	enum nft_bitwise_ops	op:8;
 	u8			len;
@@ -169,8 +169,8 @@ static int nft_bitwise_init(const struct nft_ctx *ctx,
 
 	priv->len = len;
 
-	priv->sreg = nft_parse_register(tb[NFTA_BITWISE_SREG]);
-	err = nft_validate_register_load(priv->sreg, priv->len);
+	err = nft_parse_register_load(tb[NFTA_BITWISE_SREG], &priv->sreg,
+				      priv->len);
 	if (err < 0)
 		return err;
 
@@ -315,8 +315,8 @@ static int nft_bitwise_fast_init(const struct nft_ctx *ctx,
 	struct nft_bitwise_fast_expr *priv = nft_expr_priv(expr);
 	int err;
 
-	priv->sreg = nft_parse_register(tb[NFTA_BITWISE_SREG]);
-	err = nft_validate_register_load(priv->sreg, sizeof(u32));
+	err = nft_parse_register_load(tb[NFTA_BITWISE_SREG], &priv->sreg,
+				      sizeof(u32));
 	if (err < 0)
 		return err;
 

net/netfilter/nft_byteorder.c

@@ -16,7 +16,7 @@
 #include <net/netfilter/nf_tables.h>
 
 struct nft_byteorder {
-	enum nft_registers	sreg:8;
+	u8			sreg;
 	enum nft_registers	dreg:8;
 	enum nft_byteorder_ops	op:8;
 	u8			len;
@@ -131,14 +131,14 @@ static int nft_byteorder_init(const struct nft_ctx *ctx,
 		return -EINVAL;
 	}
 
-	priv->sreg = nft_parse_register(tb[NFTA_BYTEORDER_SREG]);
 	err = nft_parse_u32_check(tb[NFTA_BYTEORDER_LEN], U8_MAX, &len);
 	if (err < 0)
 		return err;
 
 	priv->len = len;
 
-	err = nft_validate_register_load(priv->sreg, priv->len);
+	err = nft_parse_register_load(tb[NFTA_BYTEORDER_SREG], &priv->sreg,
+				      priv->len);
 	if (err < 0)
 		return err;
 

net/netfilter/nft_cmp.c

@@ -18,7 +18,7 @@
 
 struct nft_cmp_expr {
 	struct nft_data		data;
-	enum nft_registers	sreg:8;
+	u8			sreg;
 	u8			len;
 	enum nft_cmp_ops	op:8;
 };
@@ -87,8 +87,7 @@ static int nft_cmp_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
 		return err;
 	}
 
-	priv->sreg = nft_parse_register(tb[NFTA_CMP_SREG]);
-	err = nft_validate_register_load(priv->sreg, desc.len);
+	err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
 	if (err < 0)
 		return err;
 
@@ -211,8 +210,7 @@ static int nft_cmp_fast_init(const struct nft_ctx *ctx,
 	if (err < 0)
 		return err;
 
-	priv->sreg = nft_parse_register(tb[NFTA_CMP_SREG]);
-	err = nft_validate_register_load(priv->sreg, desc.len);
+	err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
 	if (err < 0)
 		return err;
 

net/netfilter/nft_ct.c

@@ -28,7 +28,7 @@ struct nft_ct {
 	enum ip_conntrack_dir	dir:8;
 	union {
 		enum nft_registers	dreg:8;
-		enum nft_registers	sreg:8;
+		u8		sreg;
 	};
 };
 
@@ -608,8 +608,7 @@ static int nft_ct_set_init(const struct nft_ctx *ctx,
 		}
 	}
 
-	priv->sreg = nft_parse_register(tb[NFTA_CT_SREG]);
-	err = nft_validate_register_load(priv->sreg, len);
+	err = nft_parse_register_load(tb[NFTA_CT_SREG], &priv->sreg, len);
 	if (err < 0)
 		goto err1;
 

net/netfilter/nft_dup_netdev.c

@@ -14,7 +14,7 @@
 #include <net/netfilter/nf_dup_netdev.h>
 
 struct nft_dup_netdev {
-	enum nft_registers	sreg_dev:8;
+	u8	sreg_dev;
 };
 
 static void nft_dup_netdev_eval(const struct nft_expr *expr,
@@ -40,8 +40,8 @@ static int nft_dup_netdev_init(const struct nft_ctx *ctx,
 	if (tb[NFTA_DUP_SREG_DEV] == NULL)
 		return -EINVAL;
 
-	priv->sreg_dev = nft_parse_register(tb[NFTA_DUP_SREG_DEV]);
-	return nft_validate_register_load(priv->sreg_dev, sizeof(int));
+	return nft_parse_register_load(tb[NFTA_DUP_SREG_DEV], &priv->sreg_dev,
+				       sizeof(int));
 }
 
 static int nft_dup_netdev_dump(struct sk_buff *skb, const struct nft_expr *expr)

net/netfilter/nft_dynset.c

@@ -16,8 +16,8 @@ struct nft_dynset {
 	struct nft_set			*set;
 	struct nft_set_ext_tmpl		tmpl;
 	enum nft_dynset_ops		op:8;
-	enum nft_registers		sreg_key:8;
-	enum nft_registers		sreg_data:8;
+	u8				sreg_key;
+	u8				sreg_data;
 	bool				invert;
 	u64				timeout;
 	struct nft_expr			*expr;
@@ -154,8 +154,8 @@ static int nft_dynset_init(const struct nft_ctx *ctx,
 			return err;
 	}
 
-	priv->sreg_key = nft_parse_register(tb[NFTA_DYNSET_SREG_KEY]);
-	err = nft_validate_register_load(priv->sreg_key, set->klen);
+	err = nft_parse_register_load(tb[NFTA_DYNSET_SREG_KEY], &priv->sreg_key,
+				      set->klen);
 	if (err < 0)
 		return err;
 
@@ -165,8 +165,8 @@ static int nft_dynset_init(const struct nft_ctx *ctx,
 		if (set->dtype == NFT_DATA_VERDICT)
 			return -EOPNOTSUPP;
 
-		priv->sreg_data = nft_parse_register(tb[NFTA_DYNSET_SREG_DATA]);
-		err = nft_validate_register_load(priv->sreg_data, set->dlen);
+		err = nft_parse_register_load(tb[NFTA_DYNSET_SREG_DATA],
+					      &priv->sreg_data, set->dlen);
 		if (err < 0)
 			return err;
 	} else if (set->flags & NFT_SET_MAP)

net/netfilter/nft_exthdr.c

@@ -20,7 +20,7 @@ struct nft_exthdr {
 	u8			len;
 	u8			op;
 	enum nft_registers	dreg:8;
-	enum nft_registers	sreg:8;
+	u8			sreg;
 	u8			flags;
 };
 
@@ -403,11 +403,11 @@ static int nft_exthdr_tcp_set_init(const struct nft_ctx *ctx,
 	priv->type   = nla_get_u8(tb[NFTA_EXTHDR_TYPE]);
 	priv->offset = offset;
 	priv->len    = len;
-	priv->sreg   = nft_parse_register(tb[NFTA_EXTHDR_SREG]);
 	priv->flags  = flags;
 	priv->op     = op;
 
-	return nft_validate_register_load(priv->sreg, priv->len);
+	return nft_parse_register_load(tb[NFTA_EXTHDR_SREG], &priv->sreg,
+				       priv->len);
 }
 
 static int nft_exthdr_ipv4_init(const struct nft_ctx *ctx,

net/netfilter/nft_fwd_netdev.c

@@ -18,7 +18,7 @@
 #include <net/ip.h>
 
 struct nft_fwd_netdev {
-	enum nft_registers	sreg_dev:8;
+	u8	sreg_dev;
 };
 
 static void nft_fwd_netdev_eval(const struct nft_expr *expr,
@@ -50,8 +50,8 @@ static int nft_fwd_netdev_init(const struct nft_ctx *ctx,
 	if (tb[NFTA_FWD_SREG_DEV] == NULL)
 		return -EINVAL;
 
-	priv->sreg_dev = nft_parse_register(tb[NFTA_FWD_SREG_DEV]);
-	return nft_validate_register_load(priv->sreg_dev, sizeof(int));
+	return nft_parse_register_load(tb[NFTA_FWD_SREG_DEV], &priv->sreg_dev,
+				       sizeof(int));
 }
 
 static int nft_fwd_netdev_dump(struct sk_buff *skb, const struct nft_expr *expr)
@@ -83,8 +83,8 @@ static bool nft_fwd_netdev_offload_action(const struct nft_expr *expr)
 }
 
 struct nft_fwd_neigh {
-	enum nft_registers	sreg_dev:8;
-	enum nft_registers	sreg_addr:8;
+	u8			sreg_dev;
+	u8			sreg_addr;
 	u8			nfproto;
 };
 
@@ -162,8 +162,6 @@ static int nft_fwd_neigh_init(const struct nft_ctx *ctx,
 	    !tb[NFTA_FWD_NFPROTO])
 		return -EINVAL;
 
-	priv->sreg_dev = nft_parse_register(tb[NFTA_FWD_SREG_DEV]);
-	priv->sreg_addr = nft_parse_register(tb[NFTA_FWD_SREG_ADDR]);
 	priv->nfproto = ntohl(nla_get_be32(tb[NFTA_FWD_NFPROTO]));
 
 	switch (priv->nfproto) {
@@ -177,11 +175,13 @@ static int nft_fwd_neigh_init(const struct nft_ctx *ctx,
 		return -EOPNOTSUPP;
 	}
 
-	err = nft_validate_register_load(priv->sreg_dev, sizeof(int));
+	err = nft_parse_register_load(tb[NFTA_FWD_SREG_DEV], &priv->sreg_dev,
+				      sizeof(int));
 	if (err < 0)
 		return err;
 
-	return nft_validate_register_load(priv->sreg_addr, addr_len);
+	return nft_parse_register_load(tb[NFTA_FWD_SREG_ADDR], &priv->sreg_addr,
+				       addr_len);
 }
 
 static int nft_fwd_neigh_dump(struct sk_buff *skb, const struct nft_expr *expr)