From a69a85da458f79088c38a38db034a4d64d9c32c3 Mon Sep 17 00:00:00 2001 From: wenxu Date: Thu, 24 Oct 2019 15:52:45 +0800 Subject: [PATCH] netfilter: nft_payload: fix missing check for matching length in offloads Payload offload rule should also check the length of the match. Moreover, check for unsupported link-layer fields: nft --debug=netlink add rule firewall zones vlan id 100 ... [ payload load 2b @ link header + 0 => reg 1 ] this loads 2byte base on ll header and offset 0. This also fixes unsupported raw payload match. Fixes: 92ad6325cb89 ("netfilter: nf_tables: add hardware offload support") Signed-off-by: wenxu Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_payload.c | 38 +++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c index 22a80eb60222..5cb2d8908d2a 100644 --- a/net/netfilter/nft_payload.c +++ b/net/netfilter/nft_payload.c @@ -161,13 +161,21 @@ static int nft_payload_offload_ll(struct nft_offload_ctx *ctx, switch (priv->offset) { case offsetof(struct ethhdr, h_source): + if (priv->len != ETH_ALEN) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs, src, ETH_ALEN, reg); break; case offsetof(struct ethhdr, h_dest): + if (priv->len != ETH_ALEN) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_ETH_ADDRS, eth_addrs, dst, ETH_ALEN, reg); break; + default: + return -EOPNOTSUPP; } return 0; @@ -181,14 +189,23 @@ static int nft_payload_offload_ip(struct nft_offload_ctx *ctx, switch (priv->offset) { case offsetof(struct iphdr, saddr): + if (priv->len != sizeof(struct in_addr)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, src, sizeof(struct in_addr), reg); break; case offsetof(struct iphdr, daddr): + if (priv->len != sizeof(struct in_addr)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4, dst, sizeof(struct in_addr), reg); break; case offsetof(struct iphdr, protocol): + if (priv->len != sizeof(__u8)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto, sizeof(__u8), reg); nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT); @@ -208,14 +225,23 @@ static int nft_payload_offload_ip6(struct nft_offload_ctx *ctx, switch (priv->offset) { case offsetof(struct ipv6hdr, saddr): + if (priv->len != sizeof(struct in6_addr)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, src, sizeof(struct in6_addr), reg); break; case offsetof(struct ipv6hdr, daddr): + if (priv->len != sizeof(struct in6_addr)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6, dst, sizeof(struct in6_addr), reg); break; case offsetof(struct ipv6hdr, nexthdr): + if (priv->len != sizeof(__u8)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_BASIC, basic, ip_proto, sizeof(__u8), reg); nft_offload_set_dependency(ctx, NFT_OFFLOAD_DEP_TRANSPORT); @@ -255,10 +281,16 @@ static int nft_payload_offload_tcp(struct nft_offload_ctx *ctx, switch (priv->offset) { case offsetof(struct tcphdr, source): + if (priv->len != sizeof(__be16)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src, sizeof(__be16), reg); break; case offsetof(struct tcphdr, dest): + if (priv->len != sizeof(__be16)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst, sizeof(__be16), reg); break; @@ -277,10 +309,16 @@ static int nft_payload_offload_udp(struct nft_offload_ctx *ctx, switch (priv->offset) { case offsetof(struct udphdr, source): + if (priv->len != sizeof(__be16)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, src, sizeof(__be16), reg); break; case offsetof(struct udphdr, dest): + if (priv->len != sizeof(__be16)) + return -EOPNOTSUPP; + NFT_OFFLOAD_MATCH(FLOW_DISSECTOR_KEY_PORTS, tp, dst, sizeof(__be16), reg); break;