Subject: Re: [PATCH] net/ncsi: fix checksum validation in response packet
To: Gavin Shan <gwshan@linux.vnet.ibm.com>,
        David Miller <davem@davemloft.net>
References: <1492160197-13816-1-git-send-email-clg@kaod.org>
 <20170417.133619.1515025171498720534.davem@davemloft.net>
 <20170418000600.GA4978@gwshan>
Cc: joel@jms.id.au, netdev@vger.kernel.org, linux-kernel@vger.kernel.org
From: =?UTF-8?Q?C=c3=a9dric_Le_Goater?= <clg@kaod.org>
Message-ID: <873115df-2bd0-65f4-22cf-2b92f3142bf2@kaod.org>
Date: Tue, 18 Apr 2017 08:16:39 +0200
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On 04/18/2017 02:06 AM, Gavin Shan wrote:
> On Mon, Apr 17, 2017 at 01:36:19PM -0400, David Miller wrote:
>> From: C?dric Le Goater <clg@kaod.org>
>> Date: Fri, 14 Apr 2017 10:56:37 +0200
>>
>>> htonl was used instead of ntohl. Surely a typo.
>>>
>>> Signed-off-by: C?dric Le Goater <clg@kaod.org>
>>
>> I don't think so, "checksum" is of type "u32" thus is in host byte
>> order.  Therefore "htonl()" is correct.
>>
> 
> Yeah, "htonl()" is correct here. "*pchecksum" is in big-endian.
> I want to know how C?dric thinks it's a problem. I guess he might
> encounter the issue on the emulated NCSI channel by QEMU. 

yes exactly. my bad. After a second look this is correct. Sorry for
the noise. 

> On BCM5718 or BCM5719, the checksum in AEN and response packet 
> are zero'd, meaning the software shouldn't validate it at all.

Interesting.

Thanks,

C.