@@ -6,6 +6,7 @@ import (

 	"log"

 	"net"

 	"strings"

+	"sync"

 	"github.com/dotcloud/docker/daemon/networkdriver"

 	"github.com/dotcloud/docker/daemon/networkdriver/ipallocator"

@@ -28,6 +29,24 @@ type networkInterface struct {

 	PortMappings []net.Addr // there are mappings to the host interfaces

 }

+type ifaces struct {

+	c map[string]*networkInterface

+	sync.Mutex

+}

+

+func (i *ifaces) Set(key string, n *networkInterface) {

+	i.Lock()

+	i.c[key] = n

+	i.Unlock()

+}

+

+func (i *ifaces) Get(key string) *networkInterface {

+	i.Lock()

+	res := i.c[key]

+	i.Unlock()

+	return res

+}

+

 var (

 	addrs = []string{

 		// Here we don't follow the convention of using the 1st IP of the range for the gateway.

@@ -53,7 +72,7 @@ var (

 	bridgeNetwork *net.IPNet

 	defaultBindingIP  = net.ParseIP("0.0.0.0")

-	currentInterfaces = make(map[string]*networkInterface)

+	currentInterfaces = ifaces{c: make(map[string]*networkInterface)}

 )

 func InitDriver(job *engine.Job) engine.Status {

@@ -321,9 +340,9 @@ func Allocate(job *engine.Job) engine.Status {

 	size, _ := bridgeNetwork.Mask.Size()

 	out.SetInt("IPPrefixLen", size)

-	currentInterfaces[id] = &networkInterface{

+	currentInterfaces.Set(id, &networkInterface{

 		IP: *ip,

-	}

+	})

 	out.WriteTo(job.Stdout)

@@ -334,7 +353,7 @@ func Allocate(job *engine.Job) engine.Status {

 func Release(job *engine.Job) engine.Status {

 	var (

 		id                 = job.Args[0]

-		containerInterface = currentInterfaces[id]

+		containerInterface = currentInterfaces.Get(id)

 		ip                 net.IP

 		port               int

 		proto              string

@@ -383,7 +402,7 @@ func AllocatePort(job *engine.Job) engine.Status {

 		origHostPort  = job.GetenvInt("HostPort")

 		containerPort = job.GetenvInt("ContainerPort")

 		proto         = job.Getenv("Proto")

-		network       = currentInterfaces[id]

+		network       = currentInterfaces.Get(id)

 	)

 	if hostIP != "" {