[PATCH 09/13] netfilter: nft_range: validate operation netlink attribute
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: 2016-10-21 10:12:19
Also in:
netfilter-devel
Subsystem:
netfilter, networking [general], the rest · Maintainers:
Pablo Neira Ayuso, Florian Westphal, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Use nft_parse_u32_check() to make sure we don't get a value over the
unsigned 8-bit integer. Moreover, make sure this value doesn't go over
the two supported range comparison modes.
Fixes: 9286c2eb1fda ("netfilter: nft_range: validate operation netlink attribute")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
net/netfilter/nft_range.c | 16 +++++++++++++++-
1 file changed, 15 insertions(+), 1 deletion(-)
diff --git a/net/netfilter/nft_range.c b/net/netfilter/nft_range.c
index c6d5358482d1..9bc4586c3006 100644
--- a/net/netfilter/nft_range.c
+++ b/net/netfilter/nft_range.c@@ -59,6 +59,7 @@ static int nft_range_init(const struct nft_ctx *ctx, const struct nft_expr *expr struct nft_range_expr *priv = nft_expr_priv(expr); struct nft_data_desc desc_from, desc_to; int err; + u32 op; err = nft_data_init(NULL, &priv->data_from, sizeof(priv->data_from), &desc_from, tb[NFTA_RANGE_FROM_DATA]);
@@ -80,7 +81,20 @@ static int nft_range_init(const struct nft_ctx *ctx, const struct nft_expr *expr if (err < 0) goto err2; - priv->op = ntohl(nla_get_be32(tb[NFTA_RANGE_OP])); + err = nft_parse_u32_check(tb[NFTA_RANGE_OP], U8_MAX, &op); + if (err < 0) + goto err2; + + switch (op) { + case NFT_RANGE_EQ: + case NFT_RANGE_NEQ: + break; + default: + err = -EINVAL; + goto err2; + } + + priv->op = op; priv->len = desc_from.len; return 0; err2:
--
2.1.4