From: Davide Ornaghi <d.ornaghi97@xxxxxxxxx>
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 <d.ornaghi97@xxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
---
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 ba0d3683a45d..9139ce38ea7b 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 0c43d748e23a..50429cbd42da 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:
--
2.30.2
