[U-Boot] [PATCH 1/2] efi_loader: initialize ethernet device path fully

[Heinrich Schuchardt]

On 03/23/2018 07:54 PM, Heinrich Schuchardt wrote:
>>From c38a011f699cf5a41b48c6fc547f3d0dde3d7cf9 Mon Sep 17 00:00:00 2001
> From: Patrick Wildt <patrick at blueri.se>
> Date: Fri, 23 Mar 2018 15:36:58 +0100
> Subject: [PATCH 1/2] efi_loader: initialize ethernet device path fully
> 
> Since the backing memory for a new device path can contain stale
> data we have to make sure that we either zero the buffer or that
> we initialize all variables in the overlaying structure.  This
> fixes setting the boot device path in the loaded image protocol
> in case we boot from network.>
> Signed-off-by: Patrick Wildt <patrick at blueri.se>
> ---
>  lib/efi_loader/efi_device_path.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/efi_loader/efi_device_path.c
> b/lib/efi_loader/efi_device_path.c
> index 3c735e60d3..a086c7bbd4 100644
> --- a/lib/efi_loader/efi_device_path.c
> +++ b/lib/efi_loader/efi_device_path.c
> @@ -777,7 +777,9 @@ struct efi_device_path *efi_dp_from_eth(void)
>  	ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
>  	ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
>  	ndp->dp.length = sizeof(*ndp);
> -	memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
> +	memset(&ndp->mac, 0, sizeof(ndp->mac));
> +	memcpy(&ndp->mac, eth_get_ethaddr(), ARP_HLEN);

I would prefer if you would set the memory to zero in dp_alloc(). This
would avoid the observed problem in all device paths.

> +	ndp->if_type = 1;

This line does not give any clue what 1 relates to. Please, define a
constant. EDK uses NET_IFTYPE_ETHERNET = 1.

The UEFI spec refers to RFC3232. But I could not find the corresponding
definition there.
https://www.iana.org/assignments/ianaiftype-mib/ianaiftype-mib uses the
value 6 for Ethernet interfaces.

Please, provide the RFC or IANA page from which you have taken the value
1 in a comment for the constant.

Best regards

Heinrich

>  	buf = &ndp[1];
> 
>  	*((struct efi_device_path *)buf) = END;
>