RE: [PATCH] tcp resets are misrouted

Yes. The scenario is  the kernel doesn't have enough information to routing the packet, so application depend on binding to interface to shortcut routing.  

thanks!

Shawn Lu [off-list ref] 

-----Original Message-----
From: Banerjee, Debabrata [mailto:dbanerje@akamai.com] 
Sent: Friday, October 12, 2012 10:48 AM
To: Shawn Lu; Debabrata Banerjee; Alexey Kuznetsov
Cc: netdev@vger.kernel.org; davem@davemloft.net; 
eric.dumazet@gmail.com; sol@eqv.ru
Subject: Re: [PATCH] tcp resets are misrouted

I was trying to think of the scenario you were running into, 
since it falls back to using a route lookup. You do not have 
routes on your machine that would correctly send the packet, 
I assume? Then it simply comes down to the kernel doesn't 
have enough information to know where to send the packet.

Debabrata

On 10/12/12 1:31 PM, "Shawn Lu" [off-list ref] wrote:

quoted

I admit the commit e2446eaa did break the reset in asymmetric case.
There are also many use cases in interface binding, we don't want to 
break it too... I am ok with your patch, if asymmetric route take 
higher priority. Somehow, we need  come up with another one 

to resolve 

quoted

RST lost in binding interface case, otherwise, people using 

interface 

quoted

binding will find later on that RST break again...

thanks!

Shawn Lu [off-list ref]

quoted

-----Original Message-----
From: Debabrata Banerjee [mailto:dbavatar@gmail.com]
Sent: Friday, October 12, 2012 8:57 AM
To: Alexey Kuznetsov; Banerjee, Debabrata
Cc: netdev@vger.kernel.org; davem@davemloft.net; Shawn Lu; 
eric.dumazet@gmail.com; sol@eqv.ru
Subject: Re: [PATCH] tcp resets are misrouted

On Fri, Oct 12, 2012 at 10:34 AM, Alexey Kuznetsov 
[off-list ref] wrote:


We ran into this as well and pulled that commit from our 

tree, it was 

quoted

quoted

causing serious problems. Sending the RST back on the iif was 
definitely the wrong thing to do. Patch looks good to me.

Thanks,
Debabrata