diff --git a/libnetwork/drivers/bridge/bridge_test.go b/libnetwork/drivers/bridge/bridge_test.go
index 78ecfcbd40..3fbddc6e63 100644
--- a/libnetwork/drivers/bridge/bridge_test.go
+++ b/libnetwork/drivers/bridge/bridge_test.go
@@ -476,7 +476,7 @@ func verifyV4INCEntries(networks map[string]*bridgeNetwork, numEntries int, t *t
 			if x == y {
 				continue
 			}
-			re := regexp.MustCompile(fmt.Sprintf("%s %s", x.config.BridgeName, y.config.BridgeName))
+			re := regexp.MustCompile(x.config.BridgeName + " " + y.config.BridgeName)
 			matches := re.FindAllString(string(out[:]), -1)
 			if len(matches) != 1 {
 				t.Fatalf("Cannot find expected inter-network isolation rules in IP Tables:\n%s", string(out[:]))
diff --git a/libnetwork/drivers/ipvlan/ipvlan_setup.go b/libnetwork/drivers/ipvlan/ipvlan_setup.go
index 0c39ec9d27..28d6cca4e0 100644
--- a/libnetwork/drivers/ipvlan/ipvlan_setup.go
+++ b/libnetwork/drivers/ipvlan/ipvlan_setup.go
@@ -201,5 +201,5 @@ func delDummyLink(linkName string) error {
 
 // getDummyName returns the name of a dummy parent with truncated net ID and driver prefix
 func getDummyName(netID string) string {
-	return fmt.Sprintf("%s%s", dummyPrefix, netID)
+	return dummyPrefix + netID
 }
diff --git a/libnetwork/drivers/macvlan/macvlan_setup.go b/libnetwork/drivers/macvlan/macvlan_setup.go
index 843a2e73bf..98d4bd3832 100644
--- a/libnetwork/drivers/macvlan/macvlan_setup.go
+++ b/libnetwork/drivers/macvlan/macvlan_setup.go
@@ -205,5 +205,5 @@ func delDummyLink(linkName string) error {
 
 // getDummyName returns the name of a dummy parent with truncated net ID and driver prefix
 func getDummyName(netID string) string {
-	return fmt.Sprintf("%s%s", dummyPrefix, netID)
+	return dummyPrefix + netID
 }
diff --git a/libnetwork/drivers/overlay/ov_network.go b/libnetwork/drivers/overlay/ov_network.go
index 126093fefe..0e9ca77866 100644
--- a/libnetwork/drivers/overlay/ov_network.go
+++ b/libnetwork/drivers/overlay/ov_network.go
@@ -494,7 +494,7 @@ func (n *network) restoreSubnetSandbox(s *subnet, brName, vxlanName string) erro
 	brIfaceOption := make([]osl.IfaceOption, 2)
 	brIfaceOption = append(brIfaceOption, sbox.InterfaceOptions().Address(s.gwIP))
 	brIfaceOption = append(brIfaceOption, sbox.InterfaceOptions().Bridge(true))
-	Ifaces[fmt.Sprintf("%s+%s", brName, "br")] = brIfaceOption
+	Ifaces[brName+"+br"] = brIfaceOption
 
 	err := sbox.Restore(Ifaces, nil, nil, nil)
 	if err != nil {
@@ -504,7 +504,7 @@ func (n *network) restoreSubnetSandbox(s *subnet, brName, vxlanName string) erro
 	Ifaces = make(map[string][]osl.IfaceOption)
 	vxlanIfaceOption := make([]osl.IfaceOption, 1)
 	vxlanIfaceOption = append(vxlanIfaceOption, sbox.InterfaceOptions().Master(brName))
-	Ifaces[fmt.Sprintf("%s+%s", vxlanName, "vxlan")] = vxlanIfaceOption
+	Ifaces[vxlanName+"+vxlan"] = vxlanIfaceOption
 	err = sbox.Restore(Ifaces, nil, nil, nil)
 	if err != nil {
 		return err
diff --git a/libnetwork/drivers/overlay/overlay.go b/libnetwork/drivers/overlay/overlay.go
index e624aade2e..2bae0823e1 100644
--- a/libnetwork/drivers/overlay/overlay.go
+++ b/libnetwork/drivers/overlay/overlay.go
@@ -162,7 +162,7 @@ func (d *driver) restoreEndpoints() error {
 		Ifaces := make(map[string][]osl.IfaceOption)
 		vethIfaceOption := make([]osl.IfaceOption, 1)
 		vethIfaceOption = append(vethIfaceOption, n.sbox.InterfaceOptions().Master(s.brName))
-		Ifaces[fmt.Sprintf("%s+%s", "veth", "veth")] = vethIfaceOption
+		Ifaces["veth+veth"] = vethIfaceOption
 
 		err := n.sbox.Restore(Ifaces, nil, nil, nil)
 		if err != nil {
@@ -270,7 +270,7 @@ func (d *driver) nodeJoin(advertiseAddress, bindAddress string, self bool) {
 		// If there is no cluster store there is no need to start serf.
 		if d.store != nil {
 			if err := validateSelf(advertiseAddress); err != nil {
-				logrus.Warnf("%s", err.Error())
+				logrus.Warn(err.Error())
 			}
 			err := d.serfInit()
 			if err != nil {
diff --git a/libnetwork/drivers/solaris/overlay/ov_network.go b/libnetwork/drivers/solaris/overlay/ov_network.go
index b545bc8903..4e3f9ae76f 100644
--- a/libnetwork/drivers/solaris/overlay/ov_network.go
+++ b/libnetwork/drivers/solaris/overlay/ov_network.go
@@ -331,7 +331,7 @@ func (n *network) restoreSubnetSandbox(s *subnet, brName, vxlanName string) erro
 	brIfaceOption := make([]osl.IfaceOption, 2)
 	brIfaceOption = append(brIfaceOption, sbox.InterfaceOptions().Address(s.gwIP))
 	brIfaceOption = append(brIfaceOption, sbox.InterfaceOptions().Bridge(true))
-	Ifaces[fmt.Sprintf("%s+%s", brName, "br")] = brIfaceOption
+	Ifaces[brName+"+br"] = brIfaceOption
 
 	err := sbox.Restore(Ifaces, nil, nil, nil)
 	if err != nil {
@@ -341,7 +341,7 @@ func (n *network) restoreSubnetSandbox(s *subnet, brName, vxlanName string) erro
 	Ifaces = make(map[string][]osl.IfaceOption)
 	vxlanIfaceOption := make([]osl.IfaceOption, 1)
 	vxlanIfaceOption = append(vxlanIfaceOption, sbox.InterfaceOptions().Master(brName))
-	Ifaces[fmt.Sprintf("%s+%s", vxlanName, "vxlan")] = vxlanIfaceOption
+	Ifaces[vxlanName+"+vxlan"] = vxlanIfaceOption
 	err = sbox.Restore(Ifaces, nil, nil, nil)
 	if err != nil {
 		return err
diff --git a/libnetwork/drivers/solaris/overlay/overlay.go b/libnetwork/drivers/solaris/overlay/overlay.go
index 45b62b1835..92b0a4e3b8 100644
--- a/libnetwork/drivers/solaris/overlay/overlay.go
+++ b/libnetwork/drivers/solaris/overlay/overlay.go
@@ -141,7 +141,7 @@ func (d *driver) restoreEndpoints() error {
 		Ifaces := make(map[string][]osl.IfaceOption)
 		vethIfaceOption := make([]osl.IfaceOption, 1)
 		vethIfaceOption = append(vethIfaceOption, n.sbox.InterfaceOptions().Master(s.brName))
-		Ifaces[fmt.Sprintf("%s+%s", "veth", "veth")] = vethIfaceOption
+		Ifaces["veth+veth"] = vethIfaceOption
 
 		err := n.sbox.Restore(Ifaces, nil, nil, nil)
 		if err != nil {
@@ -234,7 +234,7 @@ func (d *driver) nodeJoin(advertiseAddress, bindAddress string, self bool) {
 		// If there is no cluster store there is no need to start serf.
 		if d.store != nil {
 			if err := validateSelf(advertiseAddress); err != nil {
-				logrus.Warnf("%s", err.Error())
+				logrus.Warn(err.Error())
 			}
 			err := d.serfInit()
 			if err != nil {
diff --git a/libnetwork/ipam/allocator.go b/libnetwork/ipam/allocator.go
index 71c9f39531..c4ed9a0e32 100644
--- a/libnetwork/ipam/allocator.go
+++ b/libnetwork/ipam/allocator.go
@@ -579,7 +579,7 @@ func (a *Allocator) DumpDatabase() string {
 		s = fmt.Sprintf("\n\n%s Config", as)
 		aSpace.Lock()
 		for k, config := range aSpace.subnets {
-			s = fmt.Sprintf("%s%s", s, fmt.Sprintf("\n%v: %v", k, config))
+			s += fmt.Sprintf("\n%v: %v", k, config)
 			if config.Range == nil {
 				a.retrieveBitmask(k, config.Pool)
 			}
@@ -589,7 +589,7 @@ func (a *Allocator) DumpDatabase() string {
 
 	s = fmt.Sprintf("%s\n\nBitmasks", s)
 	for k, bm := range a.addresses {
-		s = fmt.Sprintf("%s%s", s, fmt.Sprintf("\n%s: %s", k, bm))
+		s += fmt.Sprintf("\n%s: %s", k, bm)
 	}
 
 	return s
diff --git a/libnetwork/types/types.go b/libnetwork/types/types.go
index da113e24cd..164b18096c 100644
--- a/libnetwork/types/types.go
+++ b/libnetwork/types/types.go
@@ -129,11 +129,11 @@ func (p *PortBinding) GetCopy() PortBinding {
 func (p *PortBinding) String() string {
 	ret := fmt.Sprintf("%s/", p.Proto)
 	if p.IP != nil {
-		ret = fmt.Sprintf("%s%s", ret, p.IP.String())
+		ret += p.IP.String()
 	}
 	ret = fmt.Sprintf("%s:%d/", ret, p.Port)
 	if p.HostIP != nil {
-		ret = fmt.Sprintf("%s%s", ret, p.HostIP.String())
+		ret += p.HostIP.String()
 	}
 	ret = fmt.Sprintf("%s:%d", ret, p.HostPort)
 	return ret