netdev - Re: suspicius csum initialization in vmxnet3_rx

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Date:   Thu, 31 May 2018 11:02:34 -0700
From:   Ronak Doshi <doshir@...are.com>
To:     Paolo Abeni <pabeni@...hat.com>
CC:     Guolin Yang <gyang@...are.com>,
        Neil Horman <nhorman@...driver.com>,
        Boon Ang <bang@...are.com>, Louis Luo <llouis@...are.com>,
        <netdev@...r.kernel.org>
Subject: Re: suspicius csum initialization in vmxnet3_rx_csum

On Wed, 30 May 2018, Paolo Abeni wrote:

> Hi,
> 
> On Thu, 2018-05-24 at 21:48 +0000, Guolin Yang wrote:
> > Yes, that code  is not correct, we should fix that code
> 
> Did you have any chance to address the issue and/or to give a more in-
> deepth look to the change proposed in my initial email?
>  
Hi Paolo,

Can you provide the esx build you are using? It can be found using 
"vmware -vl" on ESX host.

Did you try your proposed fix and did it work? Are you sure the packet
hits the below if block and not the else block? I still don't think the
ICMP packet will go through the below if block.

   if (gdesc->rcd.csum) {
	skb->csum = htons(gdesc->rcd.csum);
	skb->ip_summed = CHECKSUM_PARTIAL;
   } else {
	skb_checksum_none_assert(skb);
   }

The vmxnet3 emulation does not calculate rcd.csum for ICMP packet and
hence should go through the else block i.e. checksum none.

Thanks,
Ronak