libnetwork/osl: remove superfluous locks in Namespace

corhere · corhere · commit 986673873615 · 2025-05-27T11:46:13.000-04:00
The isDefault and nlHandle fields are immutable once the Namespace is
constructed.

Signed-off-by: Cory Snider &lt;csnider@mirantis.com&gt;
diff --git a/libnetwork/osl/interface_linux.go b/libnetwork/osl/interface_linux.go
@@ -804,38 +804,34 @@ func (n *Namespace) prepAdvertiseAddrs(ctx context.Context, i *Interface, ifInde
 // original name and moving it out of the sandbox.
 func (n *Namespace) RemoveInterface(i *Interface) error {
 	close(i.stopCh)
-	n.mu.Lock()
-	isDefault := n.isDefault
-	nlh := n.nlHandle
-	n.mu.Unlock()
 
 	// Find the network interface identified by the DstName attribute.
-	iface, err := nlh.LinkByName(i.DstName())
+	iface, err := n.nlHandle.LinkByName(i.DstName())
 	if err != nil {
 		return err
 	}
 
 	// Down the interface before configuring
-	if err := nlh.LinkSetDown(iface); err != nil {
+	if err := n.nlHandle.LinkSetDown(iface); err != nil {
 		return err
 	}
 
 	// TODO(aker): Why are we doing this? This would fail if the initial interface set up failed before the "dest interface" was moved into its own namespace; see https://github.com/moby/moby/pull/46315/commits/108595c2fe852a5264b78e96f9e63cda284990a6#r1331253578
-	err = nlh.LinkSetName(iface, i.SrcName())
+	err = n.nlHandle.LinkSetName(iface, i.SrcName())
 	if err != nil {
 		log.G(context.TODO()).Debugf("LinkSetName failed for interface %s: %v", i.SrcName(), err)
 		return err
 	}
 
 	// if it is a bridge just delete it.
 	if i.Bridge() {
-		if err := nlh.LinkDel(iface); err != nil {
+		if err := n.nlHandle.LinkDel(iface); err != nil {
 			return fmt.Errorf("failed deleting bridge %q: %v", i.SrcName(), err)
 		}
-	} else if !isDefault {
+	} else if !n.isDefault {
 		// Move the network interface to caller namespace.
 		// TODO(aker): What's this really doing? There are no calls to LinkDel in this package: is this code really used? (Interface.Remove() has 3 callers); see https://github.com/moby/moby/pull/46315/commits/108595c2fe852a5264b78e96f9e63cda284990a6#r1331265335
-		if err := nlh.LinkSetNsFd(iface, ns.ParseHandlerInt()); err != nil {
+		if err := n.nlHandle.LinkSetNsFd(iface, ns.ParseHandlerInt()); err != nil {
 			log.G(context.TODO()).Debugf("LinkSetNsFd failed for interface %s: %v", i.SrcName(), err)
 			return err
 		}
diff --git a/libnetwork/osl/neigh_linux.go b/libnetwork/osl/neigh_linux.go
@@ -51,13 +51,9 @@ func (n *Namespace) DeleteNeighbor(dstIP net.IP, dstMac net.HardwareAddr) error
 		return NeighborSearchError{dstIP, dstMac, false}
 	}
 
-	n.mu.Lock()
-	nlh := n.nlHandle
-	n.mu.Unlock()
-
 	var linkIndex int
 	if nh.linkDst != "" {
-		iface, err := nlh.LinkByName(nh.linkDst)
+		iface, err := n.nlHandle.LinkByName(nh.linkDst)
 		if err != nil {
 			return fmt.Errorf("could not find interface with destination name %s: %v", nh.linkDst, err)
 		}
@@ -79,13 +75,13 @@ func (n *Namespace) DeleteNeighbor(dstIP net.IP, dstMac net.HardwareAddr) error
 	// If the kernel deletion fails for the neighbor entry still remove it
 	// from the namespace cache, otherwise kernel update can fail if the
 	// neighbor moves back to the same host again.
-	if err := nlh.NeighDel(nlnh); err != nil && !errors.Is(err, os.ErrNotExist) {
+	if err := n.nlHandle.NeighDel(nlnh); err != nil && !errors.Is(err, os.ErrNotExist) {
 		log.G(context.TODO()).Warnf("Deleting neighbor IP %s, mac %s failed, %v", dstIP, dstMac, err)
 	}
 
 	// Delete the dynamic entry in the bridge
 	if nh.family > 0 {
-		if err := nlh.NeighDel(&netlink.Neigh{
+		if err := n.nlHandle.NeighDel(&netlink.Neigh{
 			LinkIndex:    linkIndex,
 			IP:           dstIP,
 			Family:       nh.family,
@@ -124,10 +120,6 @@ func (n *Namespace) AddNeighbor(dstIP net.IP, dstMac net.HardwareAddr, options .
 
 	nh.processNeighOptions(options...)
 
-	n.mu.Lock()
-	nlh := n.nlHandle
-	n.mu.Unlock()
-
 	nlnh := &netlink.Neigh{
 		IP:           dstIP,
 		HardwareAddr: dstMac,
@@ -145,14 +137,14 @@ func (n *Namespace) AddNeighbor(dstIP net.IP, dstMac net.HardwareAddr, options .
 			return fmt.Errorf("could not find the interface with name %s", nh.linkName)
 		}
 
-		iface, err := nlh.LinkByName(nh.linkDst)
+		iface, err := n.nlHandle.LinkByName(nh.linkDst)
 		if err != nil {
 			return fmt.Errorf("could not find interface with destination name %s: %v", nh.linkDst, err)
 		}
 		nlnh.LinkIndex = iface.Attrs().Index
 	}
 
-	if err := nlh.NeighSet(nlnh); err != nil {
+	if err := n.nlHandle.NeighSet(nlnh); err != nil {
 		return fmt.Errorf("could not add neighbor entry:%+v error:%v", nlnh, err)
 	}
 
