On Mon, May 15, 2017 at 06:52:00AM +0200, Björn Töpel wrote:
> From: Björn Töpel <bjorn.to...@intel.com>
>
> 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 <bjorn.to...@intel.com>
I tested the fix and it solves the problem for me! Thank you!
> ---
> 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;
>
> --
> 2.11.0
>
