4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
[ Upstream commit 7931d32955e09d0a11b1fe0b6aac1bfa061c005c ]
register store validation for NFT_DATA_VALUE is conditional, however,
the datatype is always either NFT_DATA_VALUE or NFT_DATA_VERDICT. This
only requires a new helper function to infer the register type from the
set datatype so this conditional check can be removed. Otherwise,
pointer to chain object can be leaked through the registers.
Fixes: 96518518cc41 ("netfilter: add nftables")
Reported-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
include/net/netfilter/nf_tables.h | 5 +++++
net/netfilter/nf_tables_api.c | 8 ++++----
net/netfilter/nft_lookup.c | 3 ++-
3 files changed, 11 insertions(+), 5 deletions(-)
diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 9ce7837520f39..4a0f51c2b3b91 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -445,6 +445,11 @@ static inline void *nft_set_priv(const struct nft_set *set)
return (void *)set->data;
}
+static inline enum nft_data_types nft_set_datatype(const struct nft_set *set)
+{
+ return set->dtype == NFT_DATA_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE;
+}
+
static inline bool nft_set_gc_is_pending(const struct nft_set *s)
{
return refcount_read(&s->refs) != 1;
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 2c31470dd61f5..f2611406af141 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -4154,8 +4154,7 @@ static int nf_tables_fill_setelem(struct sk_buff *skb,
if (nft_set_ext_exists(ext, NFT_SET_EXT_DATA) &&
nft_data_dump(skb, NFTA_SET_ELEM_DATA, nft_set_ext_data(ext),
- set->dtype == NFT_DATA_VERDICT ? NFT_DATA_VERDICT : NFT_DATA_VALUE,
- set->dlen) < 0)
+ nft_set_datatype(set), set->dlen) < 0)
goto nla_put_failure;
if (nft_set_ext_exists(ext, NFT_SET_EXT_EXPR) &&
@@ -7655,6 +7654,9 @@ static int nft_validate_register_store(const struct nft_ctx *ctx,
return 0;
default:
+ if (type != NFT_DATA_VALUE)
+ return -EINVAL;
+
if (reg < NFT_REG_1 * NFT_REG_SIZE / NFT_REG32_SIZE)
return -EINVAL;
if (len == 0)
@@ -7663,8 +7665,6 @@ static int nft_validate_register_store(const struct nft_ctx *ctx,
FIELD_SIZEOF(struct nft_regs, data))
return -ERANGE;
- if (data != NULL && type != NFT_DATA_VALUE)
- return -EINVAL;
return 0;
}
}
diff --git a/net/netfilter/nft_lookup.c b/net/netfilter/nft_lookup.c
index 3c380fb326511..bb8bd562c1ba2 100644
--- a/net/netfilter/nft_lookup.c
+++ b/net/netfilter/nft_lookup.c
@@ -101,7 +101,8 @@ static int nft_lookup_init(const struct nft_ctx *ctx,
return -EINVAL;
err = nft_parse_register_store(ctx, tb[NFTA_LOOKUP_DREG],
- &priv->dreg, NULL, set->dtype,
+ &priv->dreg, NULL,
+ nft_set_datatype(set),
set->dlen);
if (err < 0)
return err;
--
2.43.0
