From 8059918a1377f2f1fff06af4f5a4ed3d5acd6bc4 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Mon, 29 Jan 2024 13:12:33 +0100 Subject: netfilter: nft_ct: sanitize layer 3 and 4 protocol number in custom expectations - Disallow families other than NFPROTO_{IPV4,IPV6,INET}. - Disallow layer 4 protocol with no ports, since destination port is a mandatory attribute for this object. Fixes: 857b46027d6f ("netfilter: nft_ct: add ct expectations support") Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_ct.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) (limited to 'net') diff --git a/net/netfilter/nft_ct.c b/net/netfilter/nft_ct.c index 86bb9d7797d9..aac98a3c966e 100644 --- a/net/netfilter/nft_ct.c +++ b/net/netfilter/nft_ct.c @@ -1250,7 +1250,31 @@ static int nft_ct_expect_obj_init(const struct nft_ctx *ctx, if (tb[NFTA_CT_EXPECT_L3PROTO]) priv->l3num = ntohs(nla_get_be16(tb[NFTA_CT_EXPECT_L3PROTO])); + switch (priv->l3num) { + case NFPROTO_IPV4: + case NFPROTO_IPV6: + if (priv->l3num != ctx->family) + return -EINVAL; + + fallthrough; + case NFPROTO_INET: + break; + default: + return -EOPNOTSUPP; + } + priv->l4proto = nla_get_u8(tb[NFTA_CT_EXPECT_L4PROTO]); + switch (priv->l4proto) { + case IPPROTO_TCP: + case IPPROTO_UDP: + case IPPROTO_UDPLITE: + case IPPROTO_DCCP: + case IPPROTO_SCTP: + break; + default: + return -EOPNOTSUPP; + } + priv->dport = nla_get_be16(tb[NFTA_CT_EXPECT_DPORT]); priv->timeout = nla_get_u32(tb[NFTA_CT_EXPECT_TIMEOUT]); priv->size = nla_get_u8(tb[NFTA_CT_EXPECT_SIZE]); -- cgit v1.2.3