From: Florian Zumbiehl <[email protected]> Date: Thu, 4 Oct 2012 18:50:20 +0200
> 6a32e4f9dd9219261f8856f817e6655114cfec2f made the vlan code skip marking > vlan-tagged frames for not locally configured vlans as PACKET_OTHERHOST if > there was an rx_handler, as the rx_handler could cause the frame to be > received > on a different (virtual) vlan-capable interface where that vlan might be > configured. > > As rx_handlers do not necessarily return RX_HANDLER_ANOTHER, this could cause > frames for unknown vlans to be delivered to the protocol stack as if they had > been received untagged. > > For example, if an ipv6 router advertisement that's tagged for a locally not > configured vlan is received on an interface with macvlan interfaces attached, > macvlan's rx_handler returns RX_HANDLER_PASS after delivering the frame to the > macvlan interfaces, which caused it to be passed to the protocol stack, > leading > to ipv6 addresses for the announced prefix being configured even though those > are completely unusable on the underlying interface. > > The fix moves marking as PACKET_OTHERHOST after the rx_handler so the > rx_handler, if there is one, sees the frame unchanged, but afterwards, > before the frame is delivered to the protocol stack, it gets marked whether > there is an rx_handler or not. > > Signed-off-by: Florian Zumbiehl <[email protected]> I agree with your analysis but I do not like your fix. This is one of the hottest paths in the networking stack and I don't want to add more "pass pointer to local variable" type interfaces. Fix this in a cleaner way please, thanks -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
