@@ -9,10 +9,8 @@ import (

 	"net"

 	"os"

 	"os/exec"

-	"path/filepath"

 	"strconv"

 	"sync"

-	"syscall"

 	"github.com/docker/docker/libnetwork/datastore"

 	"github.com/docker/docker/libnetwork/discoverapi"

@@ -891,32 +889,10 @@ func addToBridge(nlh *netlink.Handle, ifaceName, bridgeName string) error {

 func setHairpinMode(nlh *netlink.Handle, link netlink.Link, enable bool) error {

 	err := nlh.LinkSetHairpin(link, enable)

-	if err != nil && err != syscall.EINVAL {

-		// If error is not EINVAL something else went wrong, bail out right away

+	if err != nil {

 		return fmt.Errorf("unable to set hairpin mode on %s via netlink: %v",

 			link.Attrs().Name, err)

 	}

-

-	// Hairpin mode successfully set up

-	if err == nil {

-		return nil

-	}

-

-	// The netlink method failed with EINVAL which is probably because of an older

-	// kernel. Try one more time via the sysfs method.

-	path := filepath.Join("/sys/class/net", link.Attrs().Name, "brport/hairpin_mode")

-

-	var val []byte

-	if enable {

-		val = []byte{'1', '\n'}

-	} else {

-		val = []byte{'0', '\n'}

-	}

-

-	if err := os.WriteFile(path, val, 0644); err != nil {

-		return fmt.Errorf("unable to set hairpin mode on %s via sysfs: %v", link.Attrs().Name, err)

-	}

-

 	return nil

 }

@@ -124,6 +124,8 @@ func setDefaultVlan() {

 	}

 	brName := os.Args[2]

+	// IFLA_BR_VLAN_DEFAULT_PVID was added in Linux v4.4 (see torvalds/linux@0f963b7), so we can't use netlink for

+	// setting this until Docker drops support for CentOS/RHEL 7 (kernel 3.10, eol date: 2024-06-30).

 	path := filepath.Join("/sys/class/net", brName, "bridge/default_pvid")

 	data := []byte{'0', '\n'}

@@ -3,7 +3,6 @@ package osl

 import (

 	"fmt"

 	"net"

-	"regexp"

 	"sync"

 	"syscall"

 	"time"

@@ -418,30 +417,6 @@ func setInterfaceRoutes(nlh *netlink.Handle, iface netlink.Link, i *nwIface) err

 	return nil

 }

-// In older kernels (like the one in Centos 6.6 distro) sysctl does not have netns support. Therefore

-// we cannot gather the statistics from /sys/class/net/<dev>/statistics/<counter> files. Per-netns stats

-// are naturally found in /proc/net/dev in kernels which support netns (ifconfig relies on that).

-const (

-	base = "[ ]*%s:([ ]+[0-9]+){16}"

-)

-

-func scanInterfaceStats(data, ifName string, i *types.InterfaceStatistics) error {

-	var (

-		bktStr string

-		bkt    uint64

-	)

-

-	regex := fmt.Sprintf(base, ifName)

-	re := regexp.MustCompile(regex)

-	line := re.FindString(data)

-

-	_, err := fmt.Sscanf(line, "%s %d %d %d %d %d %d %d %d %d %d %d %d %d %d %d %d",

-		&bktStr, &i.RxBytes, &i.RxPackets, &i.RxErrors, &i.RxDropped, &bkt, &bkt, &bkt,

-		&bkt, &i.TxBytes, &i.TxPackets, &i.TxErrors, &i.TxDropped, &bkt, &bkt, &bkt, &bkt)

-

-	return err

-}

-

 func checkRouteConflict(nlh *netlink.Handle, address *net.IPNet, family int) error {

 	routes, err := nlh.RouteList(nil, family)

 	if err != nil {

@@ -158,32 +158,6 @@ func verifyCleanup(t *testing.T, s Sandbox, wait bool) {

 	}

 }

-func TestScanStatistics(t *testing.T) {

-	data :=

-		"Inter-|   Receive                                                |  Transmit\n" +

-			"	face |bytes    packets errs drop fifo frame compressed multicast|bytes    packets errs drop fifo colls carrier compressed\n" +

-			"  eth0:       0       0    0    0    0     0          0         0        0       0    0    0    0     0       0          0\n" +

-			" wlan0: 7787685   11141    0    0    0     0          0         0  1681390    7220    0    0    0     0       0          0\n" +

-			"    lo:  783782    1853    0    0    0     0          0         0   783782    1853    0    0    0     0       0          0\n" +

-			"lxcbr0:       0       0    0    0    0     0          0         0     9006      61    0    0    0     0       0          0\n"

-

-	i := &types.InterfaceStatistics{}

-

-	if err := scanInterfaceStats(data, "wlan0", i); err != nil {

-		t.Fatal(err)

-	}

-	if i.TxBytes != 1681390 || i.TxPackets != 7220 || i.RxBytes != 7787685 || i.RxPackets != 11141 {

-		t.Fatalf("Error scanning the statistics")

-	}

-

-	if err := scanInterfaceStats(data, "lxcbr0", i); err != nil {

-		t.Fatal(err)

-	}

-	if i.TxBytes != 9006 || i.TxPackets != 61 || i.RxBytes != 0 || i.RxPackets != 0 {

-		t.Fatalf("Error scanning the statistics")

-	}

-}

-

 func TestDisableIPv6DAD(t *testing.T) {

 	defer testutils.SetupTestOSContext(t)()