Re: [Patch] MdeModulePkg/SnpDxe: Check the value of Nii->Id before use it directly.

["Fu, Siyuan" <siyuan.fu@intel.com>]

Hi, Jiaxin

In the line you are modifying the UDNI is always not started. You should move the Nii->Id to the line after PxeStart(), not to check it here.

BestRegards
Fu Siyuan

> -----Original Message-----
> From: Wu, Jiaxin
> Sent: Thursday, December 21, 2017 3:13 PM
> To: edk2-devel@lists.01.org
> Cc: Wang, Fan <fan.wang@intel.com>; Ye, Ting <ting.ye@intel.com>; Fu,
> Siyuan <siyuan.fu@intel.com>; Wu, Jiaxin <jiaxin.wu@intel.com>
> Subject: [Patch] MdeModulePkg/SnpDxe: Check the value of Nii->Id before
> use it directly.
> 
> Nii->Id is the address of the first byte of the identifying structure
> for this network interface. This is only valid when the network interface
> is started. When the network interface is not started, this field is set
> to zero. So, we should check the value of Nii->Id before use it directly.
> 
> Cc: Wang Fan <fan.wang@intel.com>
> Cc: Ye Ting <ting.ye@intel.com>
> Cc: Fu Siyuan <siyuan.fu@intel.com>
> Contributed-under: TianoCore Contribution Agreement 1.0
> Signed-off-by: Wu Jiaxin <jiaxin.wu@intel.com>
> ---
>  MdeModulePkg/Universal/Network/SnpDxe/Snp.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/MdeModulePkg/Universal/Network/SnpDxe/Snp.c
> b/MdeModulePkg/Universal/Network/SnpDxe/Snp.c
> index 9f61aee..f0257a2 100644
> --- a/MdeModulePkg/Universal/Network/SnpDxe/Snp.c
> +++ b/MdeModulePkg/Universal/Network/SnpDxe/Snp.c
> @@ -1,9 +1,9 @@
>  /** @file
>    Implementation of driver entry point and driver binding protocol.
> 
> -Copyright (c) 2004 - 2016, Intel Corporation. All rights reserved.<BR>
> +Copyright (c) 2004 - 2017, Intel Corporation. All rights reserved.<BR>
>  This program and the accompanying materials are licensed
>  and made available under the terms and conditions of the BSD License
> which
>  accompanies this distribution. The full text of the license may be found
> at
>  http://opensource.org/licenses/bsd-license.php
> 
> @@ -333,10 +333,15 @@ SimpleNetworkDriverStart (
>      return Status;
>    }
> 
>    DEBUG ((EFI_D_INFO, "Start(): UNDI3.1 found\n"));
> 
> +  if (Nii->Id == 0) {
> +    DEBUG ((EFI_D_NET, "\nUNDI is not started.\n"));
> +    goto NiiError;
> +  }
> +
>    Pxe = (PXE_UNDI *) (UINTN) (Nii->Id);
> 
>    if (Calc8BitCksum (Pxe, Pxe->hw.Len) != 0) {
>      DEBUG ((EFI_D_NET, "\n!PXE checksum is not correct.\n"));
>      goto NiiError;
> --
> 1.9.5.msysgit.1