Merge a8f148b8 (automated)

4 files changed, 67 insertions, 4 deletions

diff --git a/runsc/cmd/exec.go b/runsc/cmd/exec.go
index 7adc23a77..5a823e89a 100644
--- a/runsc/cmd/exec.go
+++ b/runsc/cmd/exec.go
@@ -237,6 +237,16 @@ func (ex *Exec) execChildAndWait(waitStatus *syscall.WaitStatus) subcommands.Exi
 			Setctty: true,
 			Ctty:    int(tty.Fd()),
 		}
+		// TODO(b/133868570): Delete this check once Go 1.12 is no
+		// longer supported.
+		if console.CttyFdIsPostShuffle {
+			// In go1.12 and before, the Ctty FD must be the FD in
+			// the child process's FD table. Since we set
+			// cmd.Stdin/Stdout/Stderr to the tty FD, we can use
+			// any of 0, 1, or 2 here.
+			cmd.SysProcAttr.Ctty = 0
+		}
+
 	}
 
 	if err := cmd.Start(); err != nil {
diff --git a/runsc/console/ctty_1_12.go b/runsc/console/ctty_1_12.go
new file mode 100644
index 000000000..6e7a314a3
--- /dev/null
+++ b/runsc/console/ctty_1_12.go
@@ -0,0 +1,24 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build go1.12
+// +build !go1.13
+
+// TODO(b/133868570): Delete once Go 1.12 is no longer supported.
+
+package console
+
+// CttyFdIsPostShuffle indicates that in go1.12 and earlier, the
+// SysProcAttr.Ctty FD is determined "pre-shuffle" (not "post-shuffle").
+var CttyFdIsPostShuffle = false
diff --git a/runsc/console/ctty_1_13.go b/runsc/console/ctty_1_13.go
new file mode 100644
index 000000000..785d720e1
--- /dev/null
+++ b/runsc/console/ctty_1_13.go
@@ -0,0 +1,24 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+// +build go1.13
+// +build !go1.14
+
+// TODO(b/133868570): Delete once Go 1.12 is no longer supported.
+
+package console
+
+// CttyFdIsPostShuffle indicates that in go1.13 and later, the SysProcAttr.Ctty
+// FD is determined "post-shuffle".
+var CttyFdIsPostShuffle = true
diff --git a/runsc/sandbox/sandbox.go b/runsc/sandbox/sandbox.go
index 52a5dfd77..1591052cd 100644
--- a/runsc/sandbox/sandbox.go
+++ b/runsc/sandbox/sandbox.go
@@ -437,11 +437,16 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF
 		defer tty.Close()
 
 		// Set the TTY as a controlling TTY on the sandbox process.
-		// Note that the Ctty field must be the FD of the TTY in the
-		// *new* process, not this process. Since we are about to
-		// assign the TTY to nextFD, we can use that value here.
 		cmd.SysProcAttr.Setctty = true
-		cmd.SysProcAttr.Ctty = nextFD
+		cmd.SysProcAttr.Ctty = int(tty.Fd())
+		// TODO(b/133868570): Delete this check once Go 1.12 is no
+		// longer supported.
+		if console.CttyFdIsPostShuffle {
+			// In go1.12 and before, the Ctty FD must be the FD in
+			// the child process's FD table, which will be "nextFD"
+			// in this case.
+			cmd.SysProcAttr.Ctty = nextFD
+		}
 
 		// Pass the tty as all stdio fds to sandbox.
 		for i := 0; i < 3; i++ {