netfilter: nf_tables: validate NFPROTO_* family

Several expressions explicitly refer to NF_INET_* hook definitions
from expr->ops->validate, however, family is not validated.

Bail out with EOPNOTSUPP in case they are used from unsupported
families.

Fixes: 0ca743a ("netfilter: nf_tables: add compatibility layer for x_tables")
Fixes: a3c90f7 ("netfilter: nf_tables: flow offload expression")
Fixes: 2fa8419 ("netfilter: nf_tables: introduce routing expression")
Fixes: 554ced0 ("netfilter: nf_tables: add support for native socket matching")
Fixes: ad49d86 ("netfilter: nf_tables: Add synproxy support")
Fixes: 4ed8eb6 ("netfilter: nf_tables: Add native tproxy support")
Fixes: 6c47260 ("netfilter: nf_tables: add xfrm expression")
Signed-off-by: Pablo Neira Ayuso <[email protected]>

Author: ummakynes

net/netfilter/nft_compat.c

@@ -350,6 +350,12 @@ static int nft_target_validate(const struct nft_ctx *ctx,
 	unsigned int hook_mask = 0;
 	int ret;
 
+	if (ctx->family != NFPROTO_IPV4 &&
+	    ctx->family != NFPROTO_IPV6 &&
+	    ctx->family != NFPROTO_BRIDGE &&
+	    ctx->family != NFPROTO_ARP)
+		return -EOPNOTSUPP;
+
 	if (nft_is_base_chain(ctx->chain)) {
 		const struct nft_base_chain *basechain =
 						nft_base_chain(ctx->chain);
@@ -595,6 +601,12 @@ static int nft_match_validate(const struct nft_ctx *ctx,
 	unsigned int hook_mask = 0;
 	int ret;
 
+	if (ctx->family != NFPROTO_IPV4 &&
+	    ctx->family != NFPROTO_IPV6 &&
+	    ctx->family != NFPROTO_BRIDGE &&
+	    ctx->family != NFPROTO_ARP)
+		return -EOPNOTSUPP;
+
 	if (nft_is_base_chain(ctx->chain)) {
 		const struct nft_base_chain *basechain =
 						nft_base_chain(ctx->chain);

net/netfilter/nft_flow_offload.c

@@ -384,6 +384,11 @@ static int nft_flow_offload_validate(const struct nft_ctx *ctx,
 {
 	unsigned int hook_mask = (1 << NF_INET_FORWARD);
 
+	if (ctx->family != NFPROTO_IPV4 &&
+	    ctx->family != NFPROTO_IPV6 &&
+	    ctx->family != NFPROTO_INET)
+		return -EOPNOTSUPP;
+
 	return nft_chain_validate_hooks(ctx->chain, hook_mask);
 }
 

net/netfilter/nft_nat.c

@@ -143,6 +143,11 @@ static int nft_nat_validate(const struct nft_ctx *ctx,
 	struct nft_nat *priv = nft_expr_priv(expr);
 	int err;
 
+	if (ctx->family != NFPROTO_IPV4 &&
+	    ctx->family != NFPROTO_IPV6 &&
+	    ctx->family != NFPROTO_INET)
+		return -EOPNOTSUPP;
+
 	err = nft_chain_validate_dependency(ctx->chain, NFT_CHAIN_T_NAT);
 	if (err < 0)
 		return err;

net/netfilter/nft_rt.c

@@ -166,6 +166,11 @@ static int nft_rt_validate(const struct nft_ctx *ctx, const struct nft_expr *exp
 	const struct nft_rt *priv = nft_expr_priv(expr);
 	unsigned int hooks;
 
+	if (ctx->family != NFPROTO_IPV4 &&
+	    ctx->family != NFPROTO_IPV6 &&
+	    ctx->family != NFPROTO_INET)
+		return -EOPNOTSUPP;
+
 	switch (priv->key) {
 	case NFT_RT_NEXTHOP4:
 	case NFT_RT_NEXTHOP6:

net/netfilter/nft_socket.c

@@ -242,6 +242,11 @@ static int nft_socket_validate(const struct nft_ctx *ctx,
 			       const struct nft_expr *expr,
 			       const struct nft_data **data)
 {
+	if (ctx->family != NFPROTO_IPV4 &&
+	    ctx->family != NFPROTO_IPV6 &&
+	    ctx->family != NFPROTO_INET)
+		return -EOPNOTSUPP;
+
 	return nft_chain_validate_hooks(ctx->chain,
 					(1 << NF_INET_PRE_ROUTING) |
 					(1 << NF_INET_LOCAL_IN) |

net/netfilter/nft_synproxy.c

@@ -186,7 +186,6 @@ static int nft_synproxy_do_init(const struct nft_ctx *ctx,
 		break;
 #endif
 	case NFPROTO_INET:
-	case NFPROTO_BRIDGE:
 		err = nf_synproxy_ipv4_init(snet, ctx->net);
 		if (err)
 			goto nf_ct_failure;
@@ -219,7 +218,6 @@ static void nft_synproxy_do_destroy(const struct nft_ctx *ctx)
 		break;
 #endif
 	case NFPROTO_INET:
-	case NFPROTO_BRIDGE:
 		nf_synproxy_ipv4_fini(snet, ctx->net);
 		nf_synproxy_ipv6_fini(snet, ctx->net);
 		break;
@@ -253,6 +251,11 @@ static int nft_synproxy_validate(const struct nft_ctx *ctx,
 				 const struct nft_expr *expr,
 				 const struct nft_data **data)
 {
+	if (ctx->family != NFPROTO_IPV4 &&
+	    ctx->family != NFPROTO_IPV6 &&
+	    ctx->family != NFPROTO_INET)
+		return -EOPNOTSUPP;
+
 	return nft_chain_validate_hooks(ctx->chain, (1 << NF_INET_LOCAL_IN) |
 						    (1 << NF_INET_FORWARD));
 }

net/netfilter/nft_tproxy.c

@@ -316,6 +316,11 @@ static int nft_tproxy_validate(const struct nft_ctx *ctx,
 			       const struct nft_expr *expr,
 			       const struct nft_data **data)
 {
+	if (ctx->family != NFPROTO_IPV4 &&
+	    ctx->family != NFPROTO_IPV6 &&
+	    ctx->family != NFPROTO_INET)
+		return -EOPNOTSUPP;
+
 	return nft_chain_validate_hooks(ctx->chain, 1 << NF_INET_PRE_ROUTING);
 }
 

net/netfilter/nft_xfrm.c

@@ -235,6 +235,11 @@ static int nft_xfrm_validate(const struct nft_ctx *ctx, const struct nft_expr *e
 	const struct nft_xfrm *priv = nft_expr_priv(expr);
 	unsigned int hooks;
 
+	if (ctx->family != NFPROTO_IPV4 &&
+	    ctx->family != NFPROTO_IPV6 &&
+	    ctx->family != NFPROTO_INET)
+		return -EOPNOTSUPP;
+
 	switch (priv->dir) {
 	case XFRM_POLICY_IN:
 		hooks = (1 << NF_INET_FORWARD) |