kernel_optimize_test/net/openvswitch
Tao Liu 886dd7f3e9 openvswitch: meter: fix race when getting now_ms.
[ Upstream commit e4df1b0c24350a0f00229ff895a91f1072bd850d ]

We have observed meters working unexpected if traffic is 3+Gbit/s
with multiple connections.

now_ms is not pretected by meter->lock, we may get a negative
long_delta_ms when another cpu updated meter->used, then:
    delta_ms = (u32)long_delta_ms;
which will be a large value.

    band->bucket += delta_ms * band->rate;
then we get a wrong band->bucket.

OpenVswitch userspace datapath has fixed the same issue[1] some
time ago, and we port the implementation to kernel datapath.

[1] https://patchwork.ozlabs.org/project/openvswitch/patch/20191025114436.9746-1-i.maximets@ovn.org/

Fixes: 96fbc13d7e ("openvswitch: Add meter infrastructure")
Signed-off-by: Tao Liu <thomas.liu@ucloud.cn>
Suggested-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: Ilya Maximets <i.maximets@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-06-03 09:00:47 +02:00
..
actions.c
conntrack.c
conntrack.h
datapath.c
datapath.h
dp_notify.c
flow_netlink.c
flow_netlink.h
flow_table.c
flow_table.h
flow.c
flow.h
Kconfig
Makefile
meter.c
meter.h
vport-geneve.c
vport-gre.c
vport-internal_dev.c
vport-internal_dev.h
vport-netdev.c
vport-netdev.h
vport-vxlan.c
vport.c
vport.h