From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Kirsher Subject: [net 2/2] i40e/i40evf: proper update of the page_offset field Date: Tue, 6 Jun 2017 03:00:55 -0700 Message-ID: <20170606100055.63648-3-jeffrey.t.kirsher@intel.com> References: <20170606100055.63648-1-jeffrey.t.kirsher@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Cc: =?UTF-8?q?Bj=C3=B6rn=20T=C3=B6pel?= , netdev@vger.kernel.org, nhorman@redhat.com, sassmann@redhat.com, jogreene@redhat.com, Jeff Kirsher To: davem@davemloft.net Return-path: Received: from mga03.intel.com ([134.134.136.65]:4324 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751430AbdFFKBB (ORCPT ); Tue, 6 Jun 2017 06:01:01 -0400 In-Reply-To: <20170606100055.63648-1-jeffrey.t.kirsher@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: From: Björn Töpel In f8b45b74cc62 ("i40e/i40evf: Use build_skb to build frames") i40e_build_skb updates the page_offset field with an incorrect offset, which can lead to data corruption. This patch updates page_offset correctly, by properly setting truesize. Note that the bug only appears on architectures where PAGE_SIZE is 8192 or larger. Fixes: f8b45b74cc62 ("i40e/i40evf: Use build_skb to build frames") Signed-off-by: Björn Töpel Acked-by: Alexander Duyck Tested-by: Andrew Bowers Signed-off-by: Jeff Kirsher --- drivers/net/ethernet/intel/i40e/i40e_txrx.c | 3 ++- drivers/net/ethernet/intel/i40evf/i40e_txrx.c | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/intel/i40e/i40e_txrx.c b/drivers/net/ethernet/intel/i40e/i40e_txrx.c index 29321a6167a6..cd894f4023b1 100644 --- a/drivers/net/ethernet/intel/i40e/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40e/i40e_txrx.c @@ -1854,7 +1854,8 @@ static struct sk_buff *i40e_build_skb(struct i40e_ring *rx_ring, #if (PAGE_SIZE < 8192) unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2; #else - unsigned int truesize = SKB_DATA_ALIGN(size); + unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) + + SKB_DATA_ALIGN(I40E_SKB_PAD + size); #endif struct sk_buff *skb; diff --git a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c index dfe241a12ad0..12b02e530503 100644 --- a/drivers/net/ethernet/intel/i40evf/i40e_txrx.c +++ b/drivers/net/ethernet/intel/i40evf/i40e_txrx.c @@ -1190,7 +1190,8 @@ static struct sk_buff *i40e_build_skb(struct i40e_ring *rx_ring, #if (PAGE_SIZE < 8192) unsigned int truesize = i40e_rx_pg_size(rx_ring) / 2; #else - unsigned int truesize = SKB_DATA_ALIGN(size); + unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) + + SKB_DATA_ALIGN(I40E_SKB_PAD + size); #endif struct sk_buff *skb; -- 2.12.2