merge branch 'pr-1275'

Set initial console size based on process spec

LGTMs: @crosbymichael @cyphar
Closes #1275

libcontainer/container_linux.go

@@ -522,6 +522,8 @@ func (c *linuxContainer) newInitConfig(process *Process) *initConfig {
 		cfg.Rlimits = process.Rlimits
 	}
 	cfg.CreateConsole = process.ConsoleSocket != nil
+	cfg.ConsoleWidth = process.ConsoleWidth
+	cfg.ConsoleHeight = process.ConsoleHeight
 	return cfg
 }
 

libcontainer/init_linux.go

@@ -62,6 +62,8 @@ type initConfig struct {
 	ContainerId      string                `json:"containerid"`
 	Rlimits          []configs.Rlimit      `json:"rlimits"`
 	CreateConsole    bool                  `json:"create_console"`
+	ConsoleWidth     uint16                `json:"console_width"`
+	ConsoleHeight    uint16                `json:"console_height"`
 	Rootless         bool                  `json:"rootless"`
 }
 
@@ -171,12 +173,25 @@ func setupConsole(socket *os.File, config *initConfig, mount bool) error {
 	// however, that setupUser (specifically fixStdioPermissions) *will* change
 	// the UID owner of the console to be the user the process will run as (so
 	// they can actually control their console).
-	console, slavePath, err := console.NewPty()
+
+	pty, slavePath, err := console.NewPty()
 	if err != nil {
 		return err
 	}
+
+	if config.ConsoleHeight != 0 && config.ConsoleWidth != 0 {
+		err = pty.Resize(console.WinSize{
+			Height: config.ConsoleHeight,
+			Width:  config.ConsoleWidth,
+		})
+
+		if err != nil {
+			return err
+		}
+	}
+
 	// After we return from here, we don't need the console anymore.
-	defer console.Close()
+	defer pty.Close()
 
 	// Mount the console inside our rootfs.
 	if mount {
@@ -185,7 +200,7 @@ func setupConsole(socket *os.File, config *initConfig, mount bool) error {
 		}
 	}
 	// While we can access console.master, using the API is a good idea.
-	if err := utils.SendFd(socket, console.Name(), console.Fd()); err != nil {
+	if err := utils.SendFd(socket, pty.Name(), pty.Fd()); err != nil {
 		return err
 	}
 	// Now, dup over all the things.

libcontainer/process.go

@@ -47,6 +47,10 @@ type Process struct {
 	// ExtraFiles specifies additional open files to be inherited by the container
 	ExtraFiles []*os.File
 
+	// Initial sizings for the console
+	ConsoleWidth  uint16
+	ConsoleHeight uint16
+
 	// Capabilities specify the capabilities to keep when executing the process inside the container
 	// All capabilities not specified will be dropped from the processes capability mask
 	Capabilities *configs.Capabilities

tests/integration/tty.bats

@@ -116,3 +116,60 @@ function teardown() {
 	[[ ${lines[0]} =~ 1000 ]]
 	[[ ${lines[1]} =~ 5 ]]
 }
+
+@test "runc exec [tty consolesize]" {
+	# allow writing to filesystem
+	sed -i 's/"readonly": true/"readonly": false/' config.json
+
+	# run busybox detached
+	runc run -d --console-socket $CONSOLE_SOCKET test_busybox
+	[ "$status" -eq 0 ]
+
+	# make sure we're running
+	testcontainer test_busybox running
+
+	tty_info_with_consize_size=$( cat <<EOF
+{
+    "terminal": true,
+    "consoleSize": {
+	    "height": 10,
+	    "width": 110
+    },
+    "args": [
+	    "/bin/sh",
+	    "-c",
+	    "/bin/stty -a > /tmp/tty-info"
+    ],
+    "cwd": "/"
+}
+EOF
+	)
+
+	# run the exec
+	runc exec --pid-file pid.txt -d --console-socket $CONSOLE_SOCKET -p <( echo $tty_info_with_consize_size ) test_busybox
+	[ "$status" -eq 0 ]
+
+	# check the pid was generated
+	[ -e pid.txt ]
+
+	#wait user process to finish
+	timeout 1 tail --pid=$(head -n 1 pid.txt) -f /dev/null
+
+	tty_info=$( cat <<EOF
+{
+    "args": [
+	"/bin/cat",
+	"/tmp/tty-info"
+    ],
+    "cwd": "/"
+}
+EOF
+	)
+
+	# run the exec
+	runc exec -p <( echo $tty_info ) test_busybox
+	[ "$status" -eq 0 ]
+
+	# test tty width and height against original process.json
+	[[ ${lines[0]} =~ "rows 10; columns 110" ]]
+}

utils_linux.go

@@ -108,6 +108,12 @@ func newProcess(p specs.Process) (*libcontainer.Process, error) {
 		NoNewPrivileges: &p.NoNewPrivileges,
 		AppArmorProfile: p.ApparmorProfile,
 	}
+
+	if p.ConsoleSize != nil {
+		lp.ConsoleWidth = uint16(p.ConsoleSize.Width)
+		lp.ConsoleHeight = uint16(p.ConsoleSize.Height)
+	}
+
 	if p.Capabilities != nil {
 		lp.Capabilities = &configs.Capabilities{}
 		lp.Capabilities.Bounding = p.Capabilities.Bounding