Create new process group on process startup.

Clean up by sending SIGKILL to the whole process group.

client/driver/executor/executor.go

@@ -224,6 +224,11 @@ func (e *UniversalExecutor) LaunchCmd(command *ExecCommand) (*ProcessState, erro
 	// set the task dir as the working directory for the command
 	e.cmd.Dir = e.ctx.TaskDir
 
+	// start command in separate process group
+	if err := e.setNewProcessGroup(); err != nil {
+		return nil, err
+	}
+
 	// configuring the chroot, resource container, and start the plugin
 	// process in the chroot.
 	if err := e.configureIsolation(); err != nil {

client/driver/executor/executor_basic.go

@@ -29,6 +29,10 @@ func (e *UniversalExecutor) configureIsolation() error {
 	return nil
 }
 
+func (e *UniversalExecutor) setNewProcessGroup() error {
+	return nil
+}
+
 func (e *UniversalExecutor) Stats() (*cstructs.TaskResourceUsage, error) {
 	pidStats, err := e.pidStats()
 	if err != nil {

client/driver/executor/executor_linux.go

@@ -330,6 +330,15 @@ func DestroyCgroup(groups *cgroupConfig.Cgroup, cgPaths map[string]string, execu
 	return mErrs.ErrorOrNil()
 }
 
+// configure new process group for child process
+func (e *UniversalExecutor) setNewProcessGroup() error {
+	if e.cmd.SysProcAttr == nil {
+		e.cmd.SysProcAttr = &syscall.SysProcAttr{}
+	}
+	e.cmd.SysProcAttr.Setpgid = true
+	return nil
+}
+
 // getCgroupManager returns the correct libcontainer cgroup manager.
 func getCgroupManager(groups *cgroupConfig.Cgroup, paths map[string]string) cgroups.Manager {
 	return &cgroupFs.Manager{Cgroups: groups, Paths: paths}

client/driver/raw_exec.go

@@ -292,8 +292,8 @@ func (h *rawExecHandle) run() {
 	ps, werr := h.executor.Wait()
 	close(h.doneCh)
 	if ps.ExitCode == 0 && werr != nil {
-		if e := killProcess(h.userPid); e != nil {
-			h.logger.Printf("[ERR] driver.raw_exec: error killing user process: %v", e)
+		if e := killProcessGroup(h.userPid); e != nil {
+			h.logger.Printf("[ERR] driver.raw_exec: error killing user process group: %v", e)
 		}
 	}
 

client/driver/utils.go

@@ -8,6 +8,7 @@ import (
 	"os/exec"
 	"path/filepath"
 	"strings"
+	"syscall"
 	"time"
 
 	"github.com/hashicorp/go-multierror"
@@ -109,6 +110,15 @@ func killProcess(pid int) error {
 	return proc.Kill()
 }
 
+// killProcessGroup kills a process group with the given pid
+func killProcessGroup(pid int) error {
+	proc, err := os.FindProcess(pid)
+	if err != nil {
+		return err
+	}
+	return syscall.Kill(-proc.Pid, syscall.SIGKILL)
+}
+
 // destroyPlugin kills the plugin with the given pid and also kills the user
 // process
 func destroyPlugin(pluginPid int, userPid int) error {