vendor go-connections to error out if unix socket path is too long

Signed-off-by: Tibor Vass <tibor@docker.com>

vendor.conf

@@ -17,7 +17,7 @@ github.com/vdemeester/shakers 24d7f1d6a71aa5d9cbe7390e4afb66b7eef9e1b3
 golang.org/x/net 2beffdc2e92c8a3027590f898fe88f69af48a3f8 https://github.com/tonistiigi/net.git
 golang.org/x/sys 8f0908ab3b2457e2e15403d3697c9ef5cb4b57a9
 github.com/docker/go-units 8a7beacffa3009a9ac66bad506b18ffdd110cf97
-github.com/docker/go-connections f512407a188ecb16f31a33dbc9c4e4814afc1b03
+github.com/docker/go-connections 4ccf312bf1d35e5dbda654e57a9be4c3f3cd0366
 
 github.com/RackSec/srslog 456df3a81436d29ba874f3590eeeee25d666f8a5
 github.com/imdario/mergo 0.2.1

vendor/github.com/docker/go-connections/sockets/sockets.go

@@ -2,6 +2,7 @@
 package sockets
 
 import (
+	"errors"
 	"net"
 	"net/http"
 	"time"
@@ -10,6 +11,9 @@ import (
 // Why 32? See https://github.com/docker/docker/pull/8035.
 const defaultTimeout = 32 * time.Second
 
+// ErrProtocolNotAvailable is returned when a given transport protocol is not provided by the operating system.
+var ErrProtocolNotAvailable = errors.New("protocol not available")
+
 // ConfigureTransport configures the specified Transport according to the
 // specified proto and addr.
 // If the proto is unix (using a unix socket to communicate) or npipe the
@@ -17,17 +21,9 @@ const defaultTimeout = 32 * time.Second
 func ConfigureTransport(tr *http.Transport, proto, addr string) error {
 	switch proto {
 	case "unix":
-		// No need for compression in local communications.
+		return configureUnixTransport(tr, proto, addr)
-		tr.DisableCompression = true
-		tr.Dial = func(_, _ string) (net.Conn, error) {
-			return net.DialTimeout(proto, addr, defaultTimeout)
-		}
 	case "npipe":
-		// No need for compression in local communications.
+		return configureNpipeTransport(tr, proto, addr)
-		tr.DisableCompression = true
-		tr.Dial = func(_, _ string) (net.Conn, error) {
-			return DialPipe(addr, defaultTimeout)
-		}
 	default:
 		tr.Proxy = http.ProxyFromEnvironment
 		dialer, err := DialerFromEnvironment(&net.Dialer{

vendor/github.com/docker/go-connections/sockets/sockets_unix.go

@@ -3,11 +3,31 @@
 package sockets
 
 import (
+	"fmt"
 	"net"
+	"net/http"
 	"syscall"
 	"time"
 )
 
+const maxUnixSocketPathSize = len(syscall.RawSockaddrUnix{}.Path)
+
+func configureUnixTransport(tr *http.Transport, proto, addr string) error {
+	if len(addr) > maxUnixSocketPathSize {
+		return fmt.Errorf("Unix socket path %q is too long", addr)
+	}
+	// No need for compression in local communications.
+	tr.DisableCompression = true
+	tr.Dial = func(_, _ string) (net.Conn, error) {
+		return net.DialTimeout(proto, addr, defaultTimeout)
+	}
+	return nil
+}
+
+func configureNpipeTransport(tr *http.Transport, proto, addr string) error {
+	return ErrProtocolNotAvailable
+}
+
 // DialPipe connects to a Windows named pipe.
 // This is not supported on other OSes.
 func DialPipe(_ string, _ time.Duration) (net.Conn, error) {

vendor/github.com/docker/go-connections/sockets/sockets_windows.go

@@ -2,11 +2,25 @@ package sockets
 
 import (
 	"net"
+	"net/http"
 	"time"
 
 	"github.com/Microsoft/go-winio"
 )
 
+func configureUnixTransport(tr *http.Transport, proto, addr string) error {
+	return ErrProtocolNotAvailable
+}
+
+func configureNpipeTransport(tr *http.Transport, proto, addr string) error {
+	// No need for compression in local communications.
+	tr.DisableCompression = true
+	tr.Dial = func(_, _ string) (net.Conn, error) {
+		return DialPipe(addr, defaultTimeout)
+	}
+	return nil
+}
+
 // DialPipe connects to a Windows named pipe.
 func DialPipe(addr string, timeout time.Duration) (net.Conn, error) {
 	return winio.DialPipe(addr, &timeout)