Subject: Re: [PATCH v3] net: Do not include padding in TCP GRO checksum

From: Alexander Duyck <[email-masked]>
Date: Sun, 17 Nov 2013 10:24:36 -0800

On 11/16/2013 07:17 PM, Herbert Xu wrote:
> On Sat, Nov 16, 2013 at 09:02:34AM -0800, Alexander Duyck wrote:
>> That being the case though, why don't we set the flush flag on detecting
>> a bad checksum and hand it off to tcp_gro_receive instead of returning
>> NULL?  It seems like it would be in our interest to flush the flow and
>> then report the bad checksum instead of keeping the flow and handing off
>> the bad checksum to the stack.
> Because if the TCP checksum is wrong then it may belong to a
> different flow.
>
> Cheers,

It seems like it would be much more likely that a checksum error
occuring with a padded frame would corrupt the flow identifying data
then one that isn't padded.

I suppose it doesn't really matter though since checksum errors are
probably not going to be all that common of a case to deal with anyway.

Thanks,

Alex