[PATCH net-next] remove an outdated reference to T/TCP

[PATCH net-next] remove an outdated reference to T/TCP

[Rick Jones]

Remove a particularly out of date bit of comment referring to T/TCP.

Signed-off-by: Rick Jones <rick.jones2@hp.com>

---


diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 0cbb440..123e1be 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5824,14 +5824,6 @@ int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
 			 * we just ignore it, that fits the spec precisely
 			 * and avoids incompatibilities. It would be nice in
 			 * future to drop through and process the data.
-			 *
-			 * Now that TTCP is starting to be used we ought to
-			 * queue this data.
-			 * But, this leaves one open to an easy denial of
-			 * service attack, and SYN cookies can't defend
-			 * against this problem. So, we drop the data
-			 * in the interest of security over speed unless
-			 * it's still in use.
 			 */
 			kfree_skb(skb);
 			return 0;

Re: [PATCH net-next] remove an outdated reference to T/TCP

[David Miller]

From: Rick Jones <rick.jones2@hp.com>
Date: Tue,  6 Dec 2011 12:00:05 -0800 (PST)

> 
> Remove a particularly out of date bit of comment referring to T/TCP.
> 
> Signed-off-by: Rick Jones <rick.jones2@hp.com>

I think it should stay because it discusses the potential bad side
effects of queueing any data that might be in the SYN.

Re: [PATCH net-next] remove an outdated reference to T/TCP

[Rick Jones]

On 12/06/2011 12:19 PM, David Miller wrote:
> From: Rick Jones<rick.jones2@hp.com>
> Date: Tue,  6 Dec 2011 12:00:05 -0800 (PST)
>
>>
>> Remove a particularly out of date bit of comment referring to T/TCP.
>>
>> Signed-off-by: Rick Jones<rick.jones2@hp.com>
>
> I think it should stay because it discusses the potential bad side
> effects of queueing any data that might be in the SYN.

How about just the sentence that mentioned T/TCP explicitly since T/TCP 
is most definitely no longer starting to be used?-)  The rest of it can 
be discussed when/if TCP Fast Open arrives :)

rick

Re: [PATCH net-next] remove an outdated reference to T/TCP

[David Miller]

From: Rick Jones <rick.jones2@hp.com>
Date: Tue, 06 Dec 2011 13:39:23 -0800

> On 12/06/2011 12:19 PM, David Miller wrote:
>> From: Rick Jones<rick.jones2@hp.com>
>> Date: Tue,  6 Dec 2011 12:00:05 -0800 (PST)
>>
>>>
>>> Remove a particularly out of date bit of comment referring to T/TCP.
>>>
>>> Signed-off-by: Rick Jones<rick.jones2@hp.com>
>>
>> I think it should stay because it discusses the potential bad side
>> effects of queueing any data that might be in the SYN.
> 
> How about just the sentence that mentioned T/TCP explicitly since
> T/TCP is most definitely no longer starting to be used?-) The rest of
> it can be discussed when/if TCP Fast Open arrives :)

T/TCP gives the statement context, as in referencing something that
might make us want to at least theoretically consider handling the
data.

Re: [PATCH net-next] remove an outdated reference to T/TCP

[Yuchung Cheng]

On Tue, Dec 6, 2011 at 1:42 PM, David Miller <davem@davemloft.net> wrote:
>
> From: Rick Jones <rick.jones2@hp.com>
> Date: Tue, 06 Dec 2011 13:39:23 -0800
>
> > On 12/06/2011 12:19 PM, David Miller wrote:
> >> From: Rick Jones<rick.jones2@hp.com>
> >> Date: Tue,  6 Dec 2011 12:00:05 -0800 (PST)
> >>
> >>>
> >>> Remove a particularly out of date bit of comment referring to T/TCP.
> >>>
> >>> Signed-off-by: Rick Jones<rick.jones2@hp.com>
> >>
> >> I think it should stay because it discusses the potential bad side
> >> effects of queueing any data that might be in the SYN.
> >
> > How about just the sentence that mentioned T/TCP explicitly since
> > T/TCP is most definitely no longer starting to be used?-) The rest of
> > it can be discussed when/if TCP Fast Open arrives :)
>
> T/TCP gives the statement context, as in referencing something that
> might make us want to at least theoretically consider handling the
> data.
I am fine keeping the comment as is.  This does remind me to put more
comments on this part of the code in our upcoming Fast Open patch :)

Re: [PATCH net-next] remove an outdated reference to T/TCP

[Eric Dumazet]

Le mardi 06 décembre 2011 à 15:00 -0800, Yuchung Cheng a écrit :

> I am fine keeping the comment as is.  This does remind me to put more
> comments on this part of the code in our upcoming Fast Open patch :)

This sounds great.

Is TFO patch using inetpeer cache to store cookies ?

(I ask this because TFO paper I read mentions linux-2.6.34, I presume
you couldnt use inetpeer at that time since it was IPv4 only)

Re: [PATCH net-next] remove an outdated reference to T/TCP

[Yuchung Cheng]

On Wed, Dec 7, 2011 at 12:58 AM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> Le mardi 06 décembre 2011 à 15:00 -0800, Yuchung Cheng a écrit :
>
>> I am fine keeping the comment as is.  This does remind me to put more
>> comments on this part of the code in our upcoming Fast Open patch :)
>
> This sounds great.
>
> Is TFO patch using inetpeer cache to store cookies ?
>
> (I ask this because TFO paper I read mentions linux-2.6.34, I presume
> you couldnt use inetpeer at that time since it was IPv4 only)

Very interesting! I didn't know inetpeer cache earlier so we implement
own. duh! I will certainly look into it. Thanks for this tip.
From the surface, it does not seem too difficult to extend inetpeer for IPv6?

Yuchung