diff --git a/ssl/test/runner/runner.go b/ssl/test/runner/runner.go
index b52a43b76..f9678506c 100644
--- a/ssl/test/runner/runner.go
+++ b/ssl/test/runner/runner.go
@@ -1243,9 +1243,57 @@ var (
 	errUnimplemented = errors.New("child process does not implement needed flags")
 )
 
-// accept accepts a connection from listener, unless waitChan signals a process
-// exit first.
-func acceptOrWait(listener *net.TCPListener, waitChan chan error) (net.Conn, error) {
+type shimProcess struct {
+	cmd            *exec.Cmd
+	waitChan       chan error
+	listener       *net.TCPListener
+	stdout, stderr bytes.Buffer
+}
+
+// newShimProcess starts a new shim with the specified executable, flags, and
+// environment. It internally creates a TCP listener and adds the the -port
+// flag.
+func newShimProcess(shimPath string, flags []string, env []string) (*shimProcess, error) {
+	shim := new(shimProcess)
+	var err error
+	shim.listener, err = net.ListenTCP("tcp", &net.TCPAddr{IP: net.IPv6loopback})
+	if err != nil {
+		shim.listener, err = net.ListenTCP("tcp4", &net.TCPAddr{IP: net.IP{127, 0, 0, 1}})
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	flags = append([]string{"-port", strconv.Itoa(shim.listener.Addr().(*net.TCPAddr).Port)}, flags...)
+	if *useValgrind {
+		shim.cmd = valgrindOf(false, shimPath, flags...)
+	} else if *useGDB {
+		shim.cmd = gdbOf(shimPath, flags...)
+	} else if *useLLDB {
+		shim.cmd = lldbOf(shimPath, flags...)
+	} else if *useRR {
+		shim.cmd = rrOf(shimPath, flags...)
+	} else {
+		shim.cmd = exec.Command(shimPath, flags...)
+	}
+	shim.cmd.Stdin = os.Stdin
+	shim.cmd.Stdout = &shim.stdout
+	shim.cmd.Stderr = &shim.stderr
+	shim.cmd.Env = env
+
+	if err := shim.cmd.Start(); err != nil {
+		shim.listener.Close()
+		return nil, err
+	}
+
+	shim.waitChan = make(chan error, 1)
+	go func() { shim.waitChan <- shim.cmd.Wait() }()
+	return shim, nil
+}
+
+// accept returns a new TCP connection with the shim process, or returns an
+// error on timeout or shim exit.
+func (s *shimProcess) accept() (net.Conn, error) {
 	type connOrError struct {
 		conn net.Conn
 		err  error
@@ -1253,21 +1301,93 @@ func acceptOrWait(listener *net.TCPListener, waitChan chan error) (net.Conn, err
 	connChan := make(chan connOrError, 1)
 	go func() {
 		if !useDebugger() {
-			listener.SetDeadline(time.Now().Add(*idleTimeout))
+			s.listener.SetDeadline(time.Now().Add(*idleTimeout))
 		}
-		conn, err := listener.Accept()
+		conn, err := s.listener.Accept()
 		connChan <- connOrError{conn, err}
 		close(connChan)
 	}()
 	select {
 	case result := <-connChan:
 		return result.conn, result.err
-	case childErr := <-waitChan:
-		waitChan <- childErr
+	case childErr := <-s.waitChan:
+		s.waitChan <- childErr
+		if childErr == nil {
+			return nil, fmt.Errorf("child exited early with no error")
+		}
 		return nil, fmt.Errorf("child exited early: %s", childErr)
 	}
 }
 
+// wait finishes the test and waits for the shim process to exit.
+func (s *shimProcess) wait() error {
+	// Close the listener now. This is to avoid hangs if the shim tries to open
+	// more connections than expected.
+	s.listener.Close()
+
+	if !useDebugger() {
+		waitTimeout := time.AfterFunc(*idleTimeout, func() {
+			s.cmd.Process.Kill()
+		})
+		defer waitTimeout.Stop()
+	}
+
+	err := <-s.waitChan
+	s.waitChan <- err
+	return err
+}
+
+// close releases resources associated with the shimProcess. This is safe to
+// call before or after |wait|.
+func (s *shimProcess) close() {
+	s.listener.Close()
+	s.cmd.Process.Kill()
+}
+
+func doExchanges(test *testCase, shim *shimProcess, resumeCount int, transcripts *[][]byte) error {
+	config := test.config
+	if *deterministic {
+		config.Rand = &deterministicRand{}
+	}
+
+	conn, err := shim.accept()
+	if err != nil {
+		return err
+	}
+	err = doExchange(test, &config, conn, false /* not a resumption */, transcripts, 0)
+	conn.Close()
+	if err != nil {
+		return err
+	}
+
+	for i := 0; i < resumeCount; i++ {
+		var resumeConfig Config
+		if test.resumeConfig != nil {
+			resumeConfig = *test.resumeConfig
+			if !test.newSessionsOnResume {
+				resumeConfig.SessionTicketKey = config.SessionTicketKey
+				resumeConfig.ClientSessionCache = config.ClientSessionCache
+				resumeConfig.ServerSessionCache = config.ServerSessionCache
+			}
+			resumeConfig.Rand = config.Rand
+		} else {
+			resumeConfig = config
+		}
+		var connResume net.Conn
+		connResume, err = shim.accept()
+		if err != nil {
+			return err
+		}
+		err = doExchange(test, &resumeConfig, connResume, true /* resumption */, transcripts, i+1)
+		connResume.Close()
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
 func translateExpectedError(errorStr string) string {
 	if translated, ok := shimConfig.ErrorMap[errorStr]; ok {
 		return translated
@@ -1293,20 +1413,7 @@ func runTest(statusChan chan statusMsg, test *testCase, shimPath string, mallocN
 		}
 	}()
 
-	listener, err := net.ListenTCP("tcp", &net.TCPAddr{IP: net.IPv6loopback})
-	if err != nil {
-		listener, err = net.ListenTCP("tcp4", &net.TCPAddr{IP: net.IP{127, 0, 0, 1}})
-	}
-	if err != nil {
-		panic(err)
-	}
-	defer func() {
-		if listener != nil {
-			listener.Close()
-		}
-	}()
-
-	flags := []string{"-port", strconv.Itoa(listener.Addr().(*net.TCPAddr).Port)}
+	var flags []string
 	if test.testType == serverTest {
 		flags = append(flags, "-server")
 
@@ -1495,88 +1602,26 @@ func runTest(statusChan chan statusMsg, test *testCase, shimPath string, mallocN
 
 	flags = append(flags, test.flags...)
 
-	var shim *exec.Cmd
-	if *useValgrind {
-		shim = valgrindOf(false, shimPath, flags...)
-	} else if *useGDB {
-		shim = gdbOf(shimPath, flags...)
-	} else if *useLLDB {
-		shim = lldbOf(shimPath, flags...)
-	} else if *useRR {
-		shim = rrOf(shimPath, flags...)
-	} else {
-		shim = exec.Command(shimPath, flags...)
-	}
-	shim.Stdin = os.Stdin
-	var stdoutBuf, stderrBuf bytes.Buffer
-	shim.Stdout = &stdoutBuf
-	shim.Stderr = &stderrBuf
+	var env []string
 	if mallocNumToFail >= 0 {
-		shim.Env = os.Environ()
-		shim.Env = append(shim.Env, "MALLOC_NUMBER_TO_FAIL="+strconv.FormatInt(mallocNumToFail, 10))
+		env = os.Environ()
+		env = append(env, "MALLOC_NUMBER_TO_FAIL="+strconv.FormatInt(mallocNumToFail, 10))
 		if *mallocTestDebug {
-			shim.Env = append(shim.Env, "MALLOC_BREAK_ON_FAIL=1")
+			env = append(env, "MALLOC_BREAK_ON_FAIL=1")
 		}
-		shim.Env = append(shim.Env, "_MALLOC_CHECK=1")
-	}
-
-	if err := shim.Start(); err != nil {
-		panic(err)
-	}
-	statusChan <- statusMsg{test: test, statusType: statusShimStarted, pid: shim.Process.Pid}
-	waitChan := make(chan error, 1)
-	go func() { waitChan <- shim.Wait() }()
-
-	config := test.config
-
-	if *deterministic {
-		config.Rand = &deterministicRand{}
+		env = append(env, "_MALLOC_CHECK=1")
 	}
 
-	conn, err := acceptOrWait(listener, waitChan)
-	if err == nil {
-		err = doExchange(test, &config, conn, false /* not a resumption */, &transcripts, 0)
-		conn.Close()
-	}
-
-	for i := 0; err == nil && i < resumeCount; i++ {
-		var resumeConfig Config
-		if test.resumeConfig != nil {
-			resumeConfig = *test.resumeConfig
-			if !test.newSessionsOnResume {
-				resumeConfig.SessionTicketKey = config.SessionTicketKey
-				resumeConfig.ClientSessionCache = config.ClientSessionCache
-				resumeConfig.ServerSessionCache = config.ServerSessionCache
-			}
-			resumeConfig.Rand = config.Rand
-		} else {
-			resumeConfig = config
-		}
-		var connResume net.Conn
-		connResume, err = acceptOrWait(listener, waitChan)
-		if err == nil {
-			err = doExchange(test, &resumeConfig, connResume, true /* resumption */, &transcripts, i+1)
-			connResume.Close()
-		}
+	shim, err := newShimProcess(shimPath, flags, env)
+	if err != nil {
+		return err
 	}
+	defer shim.close()
 
-	// Close the listener now. This is to avoid hangs should the shim try to
-	// open more connections than expected.
-	listener.Close()
-	listener = nil
+	localErr := doExchanges(test, shim, resumeCount, &transcripts)
+	childErr := shim.wait()
 
-	var childErr error
-	if useDebugger() {
-		childErr = <-waitChan
-	} else {
-		waitTimeout := time.AfterFunc(*idleTimeout, func() {
-			shim.Process.Kill()
-		})
-		childErr = <-waitChan
-		waitTimeout.Stop()
-	}
-
-	// Now that the shim has exitted, all the settings files have been
+	// Now that the shim has exited, all the settings files have been
 	// written. Append the saved transcripts.
 	for i, transcript := range transcripts {
 		if err := appendTranscript(transcriptPrefix+strconv.Itoa(i), transcript); err != nil {
@@ -1599,8 +1644,8 @@ func runTest(statusChan chan statusMsg, test *testCase, shimPath string, mallocN
 	}
 
 	// Account for Windows line endings.
-	stdout := strings.Replace(string(stdoutBuf.Bytes()), "\r\n", "\n", -1)
-	stderr := strings.Replace(string(stderrBuf.Bytes()), "\r\n", "\n", -1)
+	stdout := strings.Replace(shim.stdout.String(), "\r\n", "\n", -1)
+	stderr := strings.Replace(shim.stderr.String(), "\r\n", "\n", -1)
 
 	// Work around an NDK / Android bug. The NDK r16 sometimes generates
 	// binaries with the DF_1_PIE, which the runtime linker on Android N
@@ -1622,22 +1667,22 @@ func runTest(statusChan chan statusMsg, test *testCase, shimPath string, mallocN
 		extraStderr = stderrParts[1]
 	}
 
-	failed := err != nil || childErr != nil
+	failed := localErr != nil || childErr != nil
 	expectedError := translateExpectedError(test.expectedError)
 	correctFailure := len(expectedError) == 0 || strings.Contains(stderr, expectedError)
 
-	localError := "none"
-	if err != nil {
-		localError = err.Error()
+	localErrString := "none"
+	if localErr != nil {
+		localErrString = localErr.Error()
 	}
 	if len(test.expectedLocalError) != 0 {
-		correctFailure = correctFailure && strings.Contains(localError, test.expectedLocalError)
+		correctFailure = correctFailure && strings.Contains(localErrString, test.expectedLocalError)
 	}
 
 	if failed != test.shouldFail || failed && !correctFailure || mustFail {
-		childError := "none"
+		childErrString := "none"
 		if childErr != nil {
-			childError = childErr.Error()
+			childErrString = childErr.Error()
 		}
 
 		var msg string
@@ -1654,7 +1699,7 @@ func runTest(statusChan chan statusMsg, test *testCase, shimPath string, mallocN
 			panic("internal error")
 		}
 
-		return fmt.Errorf("%s: local error '%s', child error '%s', stdout:\n%s\nstderr:\n%s\n%s", msg, localError, childError, stdout, stderr, extraStderr)
+		return fmt.Errorf("%s: local error '%s', child error '%s', stdout:\n%s\nstderr:\n%s\n%s", msg, localErrString, childErrString, stdout, stderr, extraStderr)
 	}
 
 	if len(extraStderr) > 0 || (!failed && len(stderr) > 0) {