diff options
| author | Laura Garcia Liebana <nevola@gmail.com> | 2016-09-14 15:00:02 +0200 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2016-09-23 09:29:02 +0200 |
| commit | 36b701fae12ac763a568037e4e7c96b5727a8b3e (patch) | |
| tree | 51cf6649e755c9ee786cfdbbd9d03a6d22baf37c /net/netfilter/nft_exthdr.c | |
| parent | 2b03bf732488a3c2e920afe22c03b82cb8477e28 (diff) | |
netfilter: nf_tables: validate maximum value of u32 netlink attributes
Fetch value and validate u32 netlink attribute. This validation is
usually required when the u32 netlink attributes are being stored in a
field whose size is smaller.
This patch revisits 4da449ae1df9 ("netfilter: nft_exthdr: Add size check
on u8 nft_exthdr attributes").
Fixes: 96518518cc41 ("netfilter: add nftables")
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Laura Garcia Liebana <nevola@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Diffstat (limited to 'net/netfilter/nft_exthdr.c')
| -rw-r--r-- | net/netfilter/nft_exthdr.c | 12 |
1 files changed, 7 insertions, 5 deletions
diff --git a/net/netfilter/nft_exthdr.c b/net/netfilter/nft_exthdr.c index 82c264e40278..a84cf3d66056 100644 --- a/net/netfilter/nft_exthdr.c +++ b/net/netfilter/nft_exthdr.c @@ -59,7 +59,7 @@ static int nft_exthdr_init(const struct nft_ctx *ctx, const struct nlattr * const tb[]) { struct nft_exthdr *priv = nft_expr_priv(expr); - u32 offset, len; + u32 offset, len, err; if (tb[NFTA_EXTHDR_DREG] == NULL || tb[NFTA_EXTHDR_TYPE] == NULL || @@ -67,11 +67,13 @@ static int nft_exthdr_init(const struct nft_ctx *ctx, tb[NFTA_EXTHDR_LEN] == NULL) return -EINVAL; - offset = ntohl(nla_get_be32(tb[NFTA_EXTHDR_OFFSET])); - len = ntohl(nla_get_be32(tb[NFTA_EXTHDR_LEN])); + err = nft_parse_u32_check(tb[NFTA_EXTHDR_OFFSET], U8_MAX, &offset); + if (err < 0) + return err; - if (offset > U8_MAX || len > U8_MAX) - return -ERANGE; + err = nft_parse_u32_check(tb[NFTA_EXTHDR_LEN], U8_MAX, &len); + if (err < 0) + return err; priv->type = nla_get_u8(tb[NFTA_EXTHDR_TYPE]); priv->offset = offset; |