From 36b701fae12ac763a568037e4e7c96b5727a8b3e Mon Sep 17 00:00:00 2001 From: Laura Garcia Liebana Date: Wed, 14 Sep 2016 15:00:02 +0200 Subject: 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 Signed-off-by: Laura Garcia Liebana Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_bitwise.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) (limited to 'net/netfilter/nft_bitwise.c') diff --git a/net/netfilter/nft_bitwise.c b/net/netfilter/nft_bitwise.c index d71cc18fa35d..31c15ed2e5fc 100644 --- a/net/netfilter/nft_bitwise.c +++ b/net/netfilter/nft_bitwise.c @@ -52,6 +52,7 @@ static int nft_bitwise_init(const struct nft_ctx *ctx, { struct nft_bitwise *priv = nft_expr_priv(expr); struct nft_data_desc d1, d2; + u32 len; int err; if (tb[NFTA_BITWISE_SREG] == NULL || @@ -61,7 +62,12 @@ static int nft_bitwise_init(const struct nft_ctx *ctx, tb[NFTA_BITWISE_XOR] == NULL) return -EINVAL; - priv->len = ntohl(nla_get_be32(tb[NFTA_BITWISE_LEN])); + err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len); + if (err < 0) + return err; + + priv->len = len; + priv->sreg = nft_parse_register(tb[NFTA_BITWISE_SREG]); err = nft_validate_register_load(priv->sreg, priv->len); if (err < 0) -- cgit v1.2.3