Fix race in netlink peer correlator

diff --git a/conn_linux.go b/conn_linux.go
index 848694d66593875ceadd78851447323f572633af..e5105e373662b959faff61da9e3ca2772859c1b9 100644 (file)
--- a/conn_linux.go
+++ b/conn_linux.go
@@ -21,6 +21,7 @@ import (
        "golang.org/x/sys/unix"
        "net"
        "strconv"
+       "sync"
        "unsafe"
 )
 
@@ -551,6 +552,7 @@ func (bind *NativeBind) routineRouteListener(device *Device) {
                endpoint *Endpoint
        }
        var reqPeer map[uint32]peerEndpointPtr
+       var reqPeerLock sync.Mutex
 
        defer unix.Close(bind.netlinkSock)
 
@@ -596,10 +598,13 @@ func (bind *NativeBind) routineRouteListener(device *Device) {
                                                        }
                                                        if attrhdr.Type == unix.RTA_OIF && attrhdr.Len == unix.SizeofRtAttr+4 {
                                                                ifidx := *(*uint32)(unsafe.Pointer(&attr[unix.SizeofRtAttr]))
+                                                               reqPeerLock.Lock()
                                                                if reqPeer == nil {
+                                                                       reqPeerLock.Unlock()
                                                                        break
                                                                }
                                                                pePtr, ok := reqPeer[hdr.Seq]
+                                                               reqPeerLock.Unlock()
                                                                if !ok {
                                                                        break
                                                                }
@@ -620,7 +625,9 @@ func (bind *NativeBind) routineRouteListener(device *Device) {
                                        }
                                        break
                                }
+                               reqPeerLock.Lock()
                                reqPeer = make(map[uint32]peerEndpointPtr)
+                               reqPeerLock.Unlock()
                                go func() {
                                        device.peers.mutex.RLock()
                                        i := uint32(1)
@@ -671,10 +678,12 @@ func (bind *NativeBind) routineRouteListener(device *Device) {
                                                        uint32(bind.lastMark),
                                                }
                                                nlmsg.hdr.Len = uint32(unsafe.Sizeof(nlmsg))
+                                               reqPeerLock.Lock()
                                                reqPeer[i] = peerEndpointPtr{
                                                        peer:     peer,
                                                        endpoint: &peer.endpoint,
                                                }
+                                               reqPeerLock.Unlock()
                                                peer.mutex.RUnlock()
                                                i++
                                                _, err := bind.netlinkCancel.Write((*[unsafe.Sizeof(nlmsg)]byte)(unsafe.Pointer(&nlmsg))[:])