Joan Raventos wrote: >>>Is this a bug in PF_PACKET? Should the socket queue be >>>emptied by packet_set_ring (called via setsockopt when >>>PACKET_RX_RING is used) so the above cannot happen? >>>Should the user-space app drain the socket queue with >>>recvfrom prior to (4) -quite unlikely in practice-? > > >>I guess the best way is not to bind the socket before having >>completed setup. We could still flush the queue to make life >>easier for userspace, not sure about that .. > > > Even w/o bind, packet_create is doing a dev_add_pack, which I think will make > pkts arrive to that socket (ie. in netif_receive_skb one can see the loops > over the rcu for both ptype_all and type-specific which seem match whenever > !ptype->dev || ptype->dev==skb->dev). > > Also the packet_mmap.txt doc does not mention bind, which probably is more a > mechanism to closely specify a dev than to signal socket readiness.
packet_create only calls dev_add_pack if a protocol is given. You can use a protocol number of 0 and then bind the socket after setting it up properly. According to your description, you first used setsockopt(..., PACKET_RX_RING), then mmap. In that case the receive queue should already get flushed by packet_set_ring (about line 1710). How did you verify that the receive queue still contains packets? - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html