From abd66e9f3cc50c9c3ba4cf609749374090a2f215 Mon Sep 17 00:00:00 2001 From: Laura Garcia Liebana Date: Mon, 14 Nov 2016 22:33:34 +0100 Subject: [PATCH] netfilter: nft_hash: validate maximum value of u32 netlink hash attribute Use the function nft_parse_u32_check() to fetch the value and validate the u32 attribute into the hash len u8 field. This patch revisits 4da449ae1df9 ("netfilter: nft_exthdr: Add size check on u8 nft_exthdr attributes"). Fixes: cb1b69b0b15b ("netfilter: nf_tables: add hash expression") Signed-off-by: Laura Garcia Liebana Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_hash.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/net/netfilter/nft_hash.c b/net/netfilter/nft_hash.c index baf694de3935..d5447a22275c 100644 --- a/net/netfilter/nft_hash.c +++ b/net/netfilter/nft_hash.c @@ -53,6 +53,7 @@ static int nft_hash_init(const struct nft_ctx *ctx, { struct nft_hash *priv = nft_expr_priv(expr); u32 len; + int err; if (!tb[NFTA_HASH_SREG] || !tb[NFTA_HASH_DREG] || @@ -67,8 +68,10 @@ static int nft_hash_init(const struct nft_ctx *ctx, priv->sreg = nft_parse_register(tb[NFTA_HASH_SREG]); priv->dreg = nft_parse_register(tb[NFTA_HASH_DREG]); - len = ntohl(nla_get_be32(tb[NFTA_HASH_LEN])); - if (len == 0 || len > U8_MAX) + err = nft_parse_u32_check(tb[NFTA_HASH_LEN], U8_MAX, &len); + if (err < 0) + return err; + if (len == 0) return -ERANGE; priv->len = len; -- 2.39.2