Data race between parseBpfData() and LinkDeserialize() #633
Description
Using github.com/vishvananda/netlink v1.1.1-0.20201231054507-6ffafa9fc19b
Go race detector reported a race between netlink.parseBpfData() and netlink.LinkDeserialize().
WARNING: DATA RACE
Write at 0x0000050ade90 by goroutine 237:
github.com/vishvananda/netlink.parseBpfData()
/go/src/github.com/cilium/cilium/vendor/github.com/vishvananda/netlink/filter_linux.go:704 +0x9d
github.com/vishvananda/netlink.(*Handle).FilterList()
/go/src/github.com/cilium/cilium/vendor/github.com/vishvananda/netlink/filter_linux.go:374 +0x9d5
github.com/vishvananda/netlink.FilterList()
/go/src/github.com/cilium/cilium/vendor/github.com/vishvananda/netlink/filter_linux.go:297 +0xf6
github.com/cilium/cilium/pkg/datapath/loader.RemoveTCFilters()
/go/src/github.com/cilium/cilium/pkg/datapath/loader/netlink.go:153 +0xb3
github.com/cilium/cilium/pkg/datapath/loader.(*Loader).reloadDatapath()
/go/src/github.com/cilium/cilium/pkg/datapath/loader/loader.go:346 +0x166d
github.com/cilium/cilium/pkg/datapath/loader.(*Loader).ReloadDatapath()
/go/src/github.com/cilium/cilium/pkg/datapath/loader/loader.go:478 +0x1f5
github.com/cilium/cilium/pkg/datapath/loader.(*Loader).CompileOrLoad()
/go/src/github.com/cilium/cilium/pkg/datapath/loader/loader.go:466 +0x704
github.com/cilium/cilium/pkg/endpoint.(*Endpoint).realizeBPFState()
/go/src/github.com/cilium/cilium/pkg/endpoint/bpf.go:720 +0x842
github.com/cilium/cilium/pkg/endpoint.(*Endpoint).regenerateBPF()
/go/src/github.com/cilium/cilium/pkg/endpoint/bpf.go:635 +0x3f5
github.com/cilium/cilium/pkg/endpoint.(*Endpoint).regenerate()
/go/src/github.com/cilium/cilium/pkg/endpoint/policy.go:416 +0xd7b
github.com/cilium/cilium/pkg/endpoint.(*EndpointRegenerationEvent).Handle()
/go/src/github.com/cilium/cilium/pkg/endpoint/events.go:65 +0x3e5
github.com/cilium/cilium/pkg/eventqueue.(*EventQueue).run.func1()
/go/src/github.com/cilium/cilium/pkg/eventqueue/eventqueue.go:256 +0x26a
sync.(*Once).doSlow()
/usr/local/go/src/sync/once.go:68 +0x109
sync.(*Once).Do()
/usr/local/go/src/sync/once.go:59 +0x68
github.com/cilium/cilium/pkg/eventqueue.(*EventQueue).run()
/go/src/github.com/cilium/cilium/pkg/eventqueue/eventqueue.go:244 +0x64
Previous read at 0x0000050ade90 by goroutine 25:
github.com/vishvananda/netlink.LinkDeserialize()
/go/src/github.com/cilium/cilium/vendor/github.com/vishvananda/netlink/link_linux.go:1792 +0x108d
github.com/vishvananda/netlink.(*Handle).LinkList()
/go/src/github.com/cilium/cilium/vendor/github.com/vishvananda/netlink/link_linux.go:1937 +0x42a
github.com/vishvananda/netlink.LinkList()
/go/src/github.com/cilium/cilium/vendor/github.com/vishvananda/netlink/link_linux.go:1915 +0x65
github.com/cilium/cilium/pkg/datapath/link.(*ifNameCache).syncCache()
/go/src/github.com/cilium/cilium/pkg/datapath/link/link.go:90 +0x45
github.com/cilium/cilium/pkg/datapath/link.init.0.func1()
/go/src/github.com/cilium/cilium/pkg/datapath/link/link.go:35 +0xc4
Apparently this is about the native variable: filter_linux.go:704:
func parseBpfData(filter Filter, data []syscall.NetlinkRouteAttr) (bool, error) {
native = nl.NativeEndian()
[...]and link_linux.go:1792:
func LinkDeserialize(hdr *unix.NlMsghdr, m []byte) (Link, error) {
[...]
case unix.IFLA_TXQLEN:
base.TxQLen = int(native.Uint32(attr.Value[0:4]))
[...]