diff options
| author | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-05-15 11:17:29 +0100 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2017-05-15 12:51:40 +0200 |
| commit | 71df14b0ce094be46d105b5a3ededd83b8e779a0 (patch) | |
| tree | b0d32758237566a91e43001780641c7a6971d2dc | |
| parent | fa803605eef39372e53d7813002d73a3fcf10c88 (diff) | |
netfilter: nf_tables: missing sanitization in data from userspace
Do not assume userspace always sends us NFT_DATA_VALUE for bitwise and
cmp expressions. Although NFT_DATA_VERDICT does not make any sense, it
is still possible to handcraft a netlink message using this incorrect
data type.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | net/netfilter/nft_bitwise.c | 19 | ||||
| -rw-r--r-- | net/netfilter/nft_cmp.c | 12 |
2 files changed, 24 insertions, 7 deletions
diff --git a/net/netfilter/nft_bitwise.c b/net/netfilter/nft_bitwise.c index 877d9acd91ef..96bd4f325b0f 100644 --- a/net/netfilter/nft_bitwise.c +++ b/net/netfilter/nft_bitwise.c @@ -83,17 +83,26 @@ static int nft_bitwise_init(const struct nft_ctx *ctx, tb[NFTA_BITWISE_MASK]); if (err < 0) return err; - if (d1.len != priv->len) - return -EINVAL; + if (d1.len != priv->len) { + err = -EINVAL; + goto err1; + } err = nft_data_init(NULL, &priv->xor, sizeof(priv->xor), &d2, tb[NFTA_BITWISE_XOR]); if (err < 0) - return err; - if (d2.len != priv->len) - return -EINVAL; + goto err1; + if (d2.len != priv->len) { + err = -EINVAL; + goto err2; + } return 0; +err2: + nft_data_uninit(&priv->xor, d2.type); +err1: + nft_data_uninit(&priv->mask, d1.type); + return err; } static int nft_bitwise_dump(struct sk_buff *skb, const struct nft_expr *expr) diff --git a/net/netfilter/nft_cmp.c b/net/netfilter/nft_cmp.c index 2b96effeadc1..8c9d0fb19118 100644 --- a/net/netfilter/nft_cmp.c +++ b/net/netfilter/nft_cmp.c @@ -201,10 +201,18 @@ nft_cmp_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[]) if (err < 0) return ERR_PTR(err); + if (desc.type != NFT_DATA_VALUE) { + err = -EINVAL; + goto err1; + } + if (desc.len <= sizeof(u32) && op == NFT_CMP_EQ) return &nft_cmp_fast_ops; - else - return &nft_cmp_ops; + + return &nft_cmp_ops; +err1: + nft_data_uninit(&data, desc.type); + return ERR_PTR(-EINVAL); } struct nft_expr_type nft_cmp_type __read_mostly = { |