On Tue, May 17, 2016 at 10:31:25PM -0700, Daniele Di Proietto wrote: > The datapath code expects the RSS hash to always be initialized. This > is enforced by checking in emc_processing() that the hash is valid, and > eventually by computing a new one. > > Unfortunately, there is another entry point to the datapath, > dpif_netdev_execute(). A packet generated by OVS (BFD frame, > packet-out from controller) doesn't have a valid RSS hash and so is > allowed to enter the datapath with an uninitialized hash value. > > This commit recomputes the hash (if not valid) in dpif_netdev_execute(). > > The only place where we would use an invalid hash is netdev-vport, in > push_udp_header(). This caused an uninitialized memory read, and a > random value to be assigned to the outer tunnel header source port. > > Reported-by: William Tu <u9012...@gmail.com> > Signed-off-by: Daniele Di Proietto <diproiet...@vmware.com>
This is well reasoned. Would there be any value in adding a comment explaining when the hash might not already be valid? Acked-by: Ben Pfaff <b...@ovn.org> _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
