Re: [PATCH] act_mirred: don't clone skb when skb isn't shared

On Sat, 2010-06-05 at 21:07 +0800, Changli Gao wrote:

Thanks. BTW: act_nat.c doesn't obey the following rule, and you plan
to remove TC_MUNGED and TC_OK2MUNGE?

2) If you munge any packet thou shalt call pskb_expand_head in the case
someone else is referencing the skb. After that you "own" the skb.
You must also tell us if it is ok to munge the packet (TC_OK2MUNGE),
this way any action downstream can stomp on the packet.

That rule still applies but it is upto the discretion of the action.
i.e if the act_nat thinks it is ok for others down the street to trample
on the packet, it should tell us so. Maybe i should change the wording
to use the word "may" in that 3rd sentence.
[I will kill (low prio) TC_OK2MUNGE but not TC_MUNGED.]

cheers,
jamal