Hi all: I have a question. I have been working to test the new sctp_drain function I am adding and have had a very difficult time getting the drain function to be called by the mbuf system...
Now here is what I most observe from some of the test cases I am building: A) All inbound packets get a cluster down in the driver routine. B) There is a much smaller limit to clusters C) The cluster allocation routine will NOT call reclaim() et.al. D) Of course since the lower drivers are allocating M_DONTWAIT even if they did I would not get the routine called. Now this brings to light a weakness in my mind on the reclaim system. 1) One of the primary things I thought the drain() functions help with is to ward off DOS attacks. 2) If drivers all use clusters only and clusters can never call a drain() function, does this not leave both TCP and SCTP weak against an attack on the cluster side of the MBUF system? 3) I can see if we are out of mbufs eventually something sending down will do a mget(..) with a M_WAIT which can spawn the drains should we not have something like this for a cluster allocation?? If we don't it seems to me the utility of the drain() fucnction is very very limited.. Regards R -- Randall R. Stewart [EMAIL PROTECTED] 815-342-5222 (cell phone) To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-net" in the body of the message
