From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pablo Neira Ayuso Subject: [PATCH 5/6] netfilter: nf_tables: check if payload length is a power of 2 Date: Wed, 19 Feb 2014 12:41:41 +0100 Message-ID: <1392810102-13877-6-git-send-email-pablo@netfilter.org> References: <1392810102-13877-1-git-send-email-pablo@netfilter.org> Cc: davem@davemloft.net, netdev@vger.kernel.org To: netfilter-devel@vger.kernel.org Return-path: In-Reply-To: <1392810102-13877-1-git-send-email-pablo@netfilter.org> Sender: netdev-owner@vger.kernel.org List-Id: netfilter-devel.vger.kernel.org From: Nikolay Aleksandrov Add a check if payload's length is a power of 2 when selecting ops. The fast ops were meant for well aligned loads, also this fixes a small bug when using a length of 3 with some offsets which causes only 1 byte to be loaded because the fast ops are chosen. Signed-off-by: Nikolay Aleksandrov Acked-by: Patrick McHardy Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nft_payload.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/netfilter/nft_payload.c b/net/netfilter/nft_payload.c index a2aeb31..85daa84 100644 --- a/net/netfilter/nft_payload.c +++ b/net/netfilter/nft_payload.c @@ -135,7 +135,8 @@ nft_payload_select_ops(const struct nft_ctx *ctx, if (len == 0 || len > FIELD_SIZEOF(struct nft_data, data)) return ERR_PTR(-EINVAL); - if (len <= 4 && IS_ALIGNED(offset, len) && base != NFT_PAYLOAD_LL_HEADER) + if (len <= 4 && is_power_of_2(len) && IS_ALIGNED(offset, len) && + base != NFT_PAYLOAD_LL_HEADER) return &nft_payload_fast_ops; else return &nft_payload_ops; -- 1.7.10.4