[19.03 backport] Do not disable sig-proxy when using a TTY

cli/command/container/run.go

@@ -115,11 +115,6 @@ func runContainer(dockerCli command.Cli, opts *runOptions, copts *containerOptio
 		config.StdinOnce = false
 	}
 
-	// Disable sigProxy when in TTY mode
-	if config.Tty {
-		opts.sigProxy = false
-	}
-
 	// Telling the Windows daemon the initial size of the tty during start makes
 	// a far better user experience rather than relying on subsequent resizes
 	// to cause things to catch up.

e2e/container/proxy_signal_test.go

@@ -0,0 +1,50 @@
+package container
+
+import (
+	"os/exec"
+	"strings"
+	"syscall"
+	"testing"
+	"time"
+
+	"github.com/docker/cli/e2e/internal/fixtures"
+	"github.com/kr/pty"
+	"gotest.tools/assert"
+	"gotest.tools/icmd"
+	"gotest.tools/poll"
+)
+
+// TestSigProxyWithTTY tests that killing the docker CLI forwards the signal to
+// the container, and kills the container's process. Test-case for moby/moby#28872
+func TestSigProxyWithTTY(t *testing.T) {
+	cmd := exec.Command("docker", "run", "-i", "-t", "--init", "--name", t.Name(), fixtures.BusyboxImage, "sleep", "30")
+	p, err := pty.Start(cmd)
+	defer func() {
+		_ = cmd.Wait()
+		_ = p.Close()
+	}()
+	assert.NilError(t, err, "failed to start container")
+	defer icmd.RunCommand("docker", "container", "rm", "-f", t.Name())
+
+	poll.WaitOn(t, containerExistsWithStatus(t, t.Name(), "running"), poll.WithDelay(100*time.Millisecond), poll.WithTimeout(5*time.Second))
+
+	pid := cmd.Process.Pid
+	t.Logf("terminating PID %d", pid)
+	err = syscall.Kill(pid, syscall.SIGTERM)
+	assert.NilError(t, err)
+
+	poll.WaitOn(t, containerExistsWithStatus(t, t.Name(), "exited"), poll.WithDelay(100*time.Millisecond), poll.WithTimeout(5*time.Second))
+}
+
+func containerExistsWithStatus(t *testing.T, containerID, status string) func(poll.LogT) poll.Result {
+	return func(poll.LogT) poll.Result {
+		result := icmd.RunCommand("docker", "inspect", "-f", "{{ .State.Status }}", containerID)
+		// ignore initial failures as the container may not yet exist (i.e., don't result.Assert(t, icmd.Success))
+
+		actual := strings.TrimSpace(result.Stdout())
+		if actual == status {
+			return poll.Success()
+		}
+		return poll.Continue("expected status %s != %s", status, actual)
+	}
+}

vendor.conf

@@ -46,6 +46,7 @@ github.com/inconshreveable/mousetrap                76626ae9c91c4f2a10f34cad8ce8
 github.com/jaguilar/vt100                           ad4c4a5743050fb7f88ce968dca9422f72a0e3f2 git://github.com/tonistiigi/vt100.git
 github.com/json-iterator/go                         0ff49de124c6f76f8494e194af75bde0f1a49a29 # 1.1.6
 github.com/konsorten/go-windows-terminal-sequences  f55edac94c9bbba5d6182a4be46d86a2c9b5b50e # v1.0.2
+github.com/kr/pty                                   521317be5ebc228a0f0ede099fa2a0b5ece22e49 # v1.1.4
 github.com/mattn/go-shellwords                      a72fbe27a1b0ed0df2f02754945044ce1456608b # v1.0.5
 github.com/matttproud/golang_protobuf_extensions    c12348ce28de40eed0136aa2b644d0ee0650e56c # v1.0.1
 github.com/Microsoft/go-winio                       84b4ab48a50763fe7b3abcef38e5205c12027fac