Revert "Revert "Add docker exec run a command in privileged mode""

This reverts commit 40b71adee390e9c06471b89ed845132b4ec80177.

Original commit (for which this is effectively a rebased version) is
72a500e9e5929b038816d8bd18d462a19e571c99 and was provided by Lei Jitang
<leijitang@huawei.com>.

Signed-off-by: Tim Dettrick <t.dettrick@uq.edu.au>
Upstream-commit: 03f65b3d0d66ccdc8b69a447b75508d594007600
Component: engine

components/engine/daemon/execdriver/native/exec.go

@@ -19,7 +19,6 @@ import (
 
 // Exec implements the exec driver Driver interface,
 // it calls libcontainer APIs to execute a container.
-// TODO(vishh): Add support for running in privileged mode.
 func (d *Driver) Exec(c *execdriver.Command, processConfig *execdriver.ProcessConfig, pipes *execdriver.Pipes, startCallback execdriver.StartCallback) (int, error) {
 	active := d.activeContainers[c.ID]
 	if active == nil {
@@ -33,6 +32,10 @@ func (d *Driver) Exec(c *execdriver.Command, processConfig *execdriver.ProcessCo
 		User: processConfig.User,
 	}
 
+	if processConfig.Privileged {
+		p.Capabilities = execdriver.GetAllCapabilities()
+	}
+
 	config := active.Config()
 	if err := setupPipes(&config, processConfig, p, pipes); err != nil {
 		return -1, err