From c4ab9da85b9df3692f861512fe6c9812f38b7471 Mon Sep 17 00:00:00 2001 From: Davide Ornaghi Date: Wed, 5 Jun 2024 13:03:45 +0200 Subject: [PATCH] netfilter: nft_inner: validate mandatory meta and payload Check for mandatory netlink attributes in payload and meta expression when used embedded from the inner expression, otherwise NULL pointer dereference is possible from userspace. Fixes: a150d122b6bd ("netfilter: nft_meta: add inner match support") Fixes: 3a07327d10a0 ("netfilter: nft_inner: support for inner tunnel header matching") Signed-off-by: Davide Ornaghi Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_meta.c | 3 +++ net/netfilter/nft_payload.c | 4 ++++ 2 files changed, 7 insertions(+) diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c index ba0d3683a45d3..9139ce38ea7b9 100644 --- a/net/netfilter/nft_meta.c +++ b/net/netfilter/nft_meta.c @@ -839,6 +839,9 @@ static int nft_meta_inner_init(const struct nft_ctx *ctx, struct nft_meta *priv = nft_expr_priv(expr); unsigned int len; + if (!tb[NFTA_META_KEY] || !tb[NFTA_META_DREG]) + return -EINVAL; + priv->key = ntohl(nla_get_be32(tb[NFTA_META_KEY])); switch (priv->key) { case NFT_META_PROTOCOL: diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c index 0c43d748e23ae..50429cbd42da4 100644 --- a/net/netfilter/nft_payload.c +++ b/net/netfilter/nft_payload.c @@ -650,6 +650,10 @@ static int nft_payload_inner_init(const struct nft_ctx *ctx, struct nft_payload *priv = nft_expr_priv(expr); u32 base; + if (!tb[NFTA_PAYLOAD_BASE] || !tb[NFTA_PAYLOAD_OFFSET] || + !tb[NFTA_PAYLOAD_LEN] || !tb[NFTA_PAYLOAD_DREG]) + return -EINVAL; + base = ntohl(nla_get_be32(tb[NFTA_PAYLOAD_BASE])); switch (base) { case NFT_PAYLOAD_TUN_HEADER: