netdev - Re: suspicius csum initialization in vmxnet3_rx

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <alpine.OSX.2.21.1805311048380.47071@doshir-m01.vmware.com>
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