From 14e2dee0996f51e0ff0d868497c7e1b90f012665 Mon Sep 17 00:00:00 2001 From: Laura Garcia Liebana Date: Tue, 13 Sep 2016 10:21:46 +0200 Subject: [PATCH] netfilter: nft_hash: fix hash overflow validation The overflow validation in the init() function establishes that the maximum value that the hash could reach is less than U32_MAX, which is likely to be true. The fix detects the overflow when the maximum hash value is less than the offset itself. Fixes: 70ca767ea1b2 ("netfilter: nft_hash: Add hash offset value") Reported-by: Liping Zhang Signed-off-by: Laura Garcia Liebana Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_hash.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c index bd12f7a..09473b4 100644 --- a/net/netfilter/nft_hash.c +++ b/net/netfilter/nft_hash.c @@ -76,7 +76,7 @@ static int nft_hash_init(const struct nft_ctx *ctx, if (priv->modulus <= 1) return -ERANGE; - if (priv->offset + priv->modulus - 1 < U32_MAX) + if (priv->offset + priv->modulus - 1 < priv->offset) return -EOVERFLOW; priv->seed = ntohl(nla_get_be32(tb[NFTA_HASH_SEED])); -- 2.7.4