Re: [PATCH PKT_SCHED 4/4]: fix CONFIG_NET_CLS_ACT skb leaks in HFSC/CBQ

[Patrick McHardy <kaber@xxxxxxxxx>]

jamal wrote:

> I dont have time, but please double check that the following still
> applies:
>
> 1) A qdisc receiving a STOLEN/QUEUED/SHOT signal from the classification
> result MUST free the packet and immediately stop processing that packet.
> The infrastructure code will clone packets if they want to steal or
> queue it.
It does now. Before there were things like "unsigned int len = skb->len"
after the call to tc_classify.

> 2) Return code of qdisc from enqueue function need to be dealt with
> care. For example if the packet is localy generated and it is a TCP
> packet you could confuse the stack by telling it the packet was dropped
> because it will retransmit (and some things will happen with the window
> adjustments).
TC_ACT_SHOT => NET_XMIT_DROP
TC_ACT_STOLEN | TC_ACT_QUEUED => NET_XMIT_SUCCESS

> 3) packets that are dropped because of a full Q should continue to
> return a XMIT_DROP (you want TCP for example to know about this)
They do.