Re: [PATCH edk2-platforms] Silicon/SynQuacer/NetsecDxe: fix buffer allocation bug

[Leif Lindholm <leif.lindholm@linaro.org>]

On Thu, Apr 12, 2018 at 11:23:49AM +0200, Ard Biesheuvel wrote:
> The receive buffers of the NETSEC driver are owned by the driver itself
> (as opposed to the protocol client in the case of the transmit path),
> and so the descriptors and the buffers (which are of a fixed size) are
> allocated in one go. The idea is that the 'buffer' member of the
> descriptor should point to a DMA aligned offset into the same allocation,
> but the code in pfdep_alloc_pkt_buf() calculates the value incorrectly,
> resulting in corruption of the descriptor metadata if the pool allocation
> happens to be DMA aligned.
> 
> Contributed-under: TianoCore Contribution Agreement 1.1
> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>

Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>

> ---
>  Silicon/Socionext/SynQuacer/Drivers/Net/NetsecDxe/netsec_for_uefi/pfdep_uefi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/Silicon/Socionext/SynQuacer/Drivers/Net/NetsecDxe/netsec_for_uefi/pfdep_uefi.c b/Silicon/Socionext/SynQuacer/Drivers/Net/NetsecDxe/netsec_for_uefi/pfdep_uefi.c
> index b43d1aaff037..0875558c08ea 100644
> --- a/Silicon/Socionext/SynQuacer/Drivers/Net/NetsecDxe/netsec_for_uefi/pfdep_uefi.c
> +++ b/Silicon/Socionext/SynQuacer/Drivers/Net/NetsecDxe/netsec_for_uefi/pfdep_uefi.c
> @@ -134,7 +134,7 @@ pfdep_alloc_pkt_buf (
>        return PFDEP_ERR_ALLOC;
>      }
>  
> -    (*pkt_handle_p)->Buffer = ALIGN_POINTER (*pkt_handle_p,
> +    (*pkt_handle_p)->Buffer = ALIGN_POINTER (*pkt_handle_p + 1,
>                                               mCpu->DmaBufferAlignment);
>    }
>  
> -- 
> 2.17.0
>