Merge pull request #4192 from lifubang/feat-ClosePipeInExec

Close sync pipe explicitly in exec

libcontainer/setns_init_linux.go

@@ -129,6 +129,11 @@ func (l *linuxSetnsInit) Init() error {
 		}
 	}
 
+	// Close the pipe to signal that we have completed our init.
+	// Please keep this because we don't want to get a pipe write error if
+	// there is an error from `execve` after all fds closed.
+	_ = l.pipe.Close()
+
 	// Close the log pipe fd so the parent's ForwardLogs can exit.
 	logrus.Debugf("setns_init: about to exec")
 	if err := l.logPipe.Close(); err != nil {

tests/integration/exec.bats

@@ -338,5 +338,5 @@ EOF
 	# Although we never close the sync socket when doing exec,
 	# but we need to keep this test to ensure this behavior is always right.
 	[ ${#lines[@]} -eq 1 ]
-	[[ ${lines[0]} = *"exec failed: unable to start container process: exec /run.sh: no such file or directory"* ]]
+	[[ ${lines[0]} = *"exec /run.sh: no such file or directory"* ]]
 }