From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sowmini Varadhan Date: Mon, 14 Mar 2016 13:46:24 -0400 Subject: [Intel-wired-lan] [PATCH v2 net-next] ixgbe: Avoid unaligned access in ixgbe_atr() for LLC packets Message-ID: <20160314174624.GG5084@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: intel-wired-lan@osuosl.org List-ID: For LLC based protocols like lldp, stp etc., the ethernet header is an 802.3 header with a h_proto that is not 0x800, 0x86dd, or even 0x806. In this world, the skb_network_header() points at the DSAP/SSAP/.. and is not likely to be NET_IP_ALIGNed in ixgbe_atr(). With LLC, drivers are not likely to correctly find IPVERSION, or "6", at hdr.ipv4->version, but will instead just needlessly trigger an unaligned access. (IPv4/IPv6 over LLC is almost never implemented). The unaligned access is thus avoidable: bail out quickly after examining first->protocol. Signed-off-by: Sowmini Varadhan --- v2: Alexander Duyck comments. drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 4d6223d..b25e603 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -7574,6 +7574,11 @@ static void ixgbe_atr(struct ixgbe_ring *ring, if (!ring->atr_sample_rate) return; + if (first->protocol != htons(ETH_P_IP) && + first->protocol != htons(ETH_P_IPV6) && + first->protocol != htons(ETH_P_ARP)) + return; + ring->atr_count++; /* snag network header to get L4 type and address */ -- 1.7.1