using the right overlay directory and remove it

Signed-off-by: Christian Goll <cgoll@suse.com>

CHANGELOG.md

@@ -59,6 +59,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Fix the issue that warewulf.conf parse does not support CIDR format. #1130
 - Reduce the number of times syncuser walks the container file system. #1209
 - Create ssh key also when calling `wwctl configure --all` #1250
+- Remove the temporary overlay dir. #1180
 
 ### Security
 

internal/app/wwctl/container/exec/child/main.go

@@ -21,6 +21,8 @@ import (
 	"github.com/warewulf/warewulf/internal/pkg/wwlog"
 )
 
+const exitEval = `$(VALU="$?" ; if [ $VALU == 0 ]; then echo write; else echo discard; fi)`
+
 func CobraRunE(cmd *cobra.Command, args []string) (err error) {
 	if os.Getpid() != 1 {
 		wwlog.Error("PID is not 1: %d", os.Getpid())
@@ -34,11 +36,13 @@ func CobraRunE(cmd *cobra.Command, args []string) (err error) {
 		os.Exit(1)
 	}
 	conf := warewulfconf.Get()
+	if overlayDir == "" {
+		overlayDir = path.Join(conf.Paths.WWChrootdir, "overlays")
+	}
 	mountPts := conf.MountsContainer
 	mountPts = append(container.InitMountPnts(binds), mountPts...)
 	// check for valid mount points
 	lowerObjects := checkMountPoints(containerName, mountPts)
-	overlayDir := conf.Paths.WWChrootdir + "/overlays"
 	// need to create a overlay, where the lower layer contains
 	// the missing mount points
 	wwlog.Verbose("for ephermal mount use tempdir %s", overlayDir)
@@ -46,6 +50,7 @@ func CobraRunE(cmd *cobra.Command, args []string) (err error) {
 	_ = os.MkdirAll(path.Join(overlayDir, "work"), os.ModePerm)
 	_ = os.MkdirAll(path.Join(overlayDir, "lower"), os.ModePerm)
 	_ = os.MkdirAll(path.Join(overlayDir, "nodeoverlay"), os.ModePerm)
+	// handle all lower object, have some extra logic if the object is a file
 	for _, obj := range lowerObjects {
 		newFile := ""
 		if !strings.HasSuffix(obj, "/") {
@@ -65,11 +70,12 @@ func CobraRunE(cmd *cobra.Command, args []string) (err error) {
 		}
 	}
 	containerPath := container.RootFsDir(containerName)
+	// running in a private PID space, so also make / private, so that nothing gets out from here
 	err = syscall.Mount("", "/", "", syscall.MS_PRIVATE|syscall.MS_REC, "")
 	if err != nil {
 		return errors.Wrap(err, "failed to mount")
 	}
-	ps1Str := fmt.Sprintf("[%s] Warewulf> ", containerName)
+	ps1Str := fmt.Sprintf("[%s|%s] Warewulf> ", exitEval, containerName)
 	if len(lowerObjects) != 0 && nodename == "" {
 		options := fmt.Sprintf("lowerdir=%s,upperdir=%s,workdir=%s",
 			path.Join(overlayDir, "lower"), containerPath, path.Join(overlayDir, "work"))

internal/app/wwctl/container/exec/child/root.go

@@ -13,13 +13,16 @@ var (
 		Args:                  cobra.MinimumNArgs(1),
 		FParseErrWhitelist:    cobra.FParseErrWhitelist{UnknownFlags: true},
 	}
-	binds    []string
-	nodename string
+	binds      []string
+	nodename   string
+	overlayDir string
 )
 
 func init() {
 	baseCmd.Flags().StringVarP(&nodename, "node", "n", "", "create ro overlay for given node")
 	baseCmd.Flags().StringArrayVarP(&binds, "bind", "b", []string{}, "bind points")
+	baseCmd.Flags().StringVar(&overlayDir, "overlaydir", "", "overlayDir")
+
 }
 
 // GetRootCommand returns the root cobra.Command for the application.

internal/app/wwctl/container/exec/main.go

@@ -12,6 +12,7 @@ import (
 	"time"
 
 	"github.com/spf13/cobra"
+	warewulfconf "github.com/warewulf/warewulf/internal/pkg/config"
 	"github.com/warewulf/warewulf/internal/pkg/container"
 	"github.com/warewulf/warewulf/internal/pkg/util"
 	"github.com/warewulf/warewulf/internal/pkg/wwlog"
@@ -20,15 +21,15 @@ import (
 /*
 fork off a process with a new PID space
 */
-func runContainedCmd(args []string) error {
-	var err error
-	if tempDir == "" {
-		tempDir, err = os.MkdirTemp(os.TempDir(), "overlay")
+func runContainedCmd(args []string) (err error) {
+	if overlayDir == "" {
+		conf := warewulfconf.Get()
+		overlayDir, err = os.MkdirTemp(conf.Paths.WWChrootdir, "overlays-")
 		if err != nil {
 			wwlog.Warn("couldn't create temp dir for overlay", err)
 		}
 		defer func() {
-			err = os.RemoveAll(tempDir)
+			err = os.RemoveAll(overlayDir)
 			if err != nil {
 				wwlog.Warn("Couldn't remove temp dir for ephermal mounts:", err)
 			}
@@ -36,7 +37,7 @@ func runContainedCmd(args []string) error {
 	}
 	logStr := fmt.Sprint(wwlog.GetLogLevel())
 	wwlog.Verbose("Running contained command: %s", args[1:])
-	c := exec.Command("/proc/self/exe", append([]string{"--loglevel", logStr, "--tempdir", tempDir, "container", "exec", "__child"}, args...)...)
+	c := exec.Command("/proc/self/exe", append([]string{"--loglevel", logStr, "--overlaydir", overlayDir, "container", "exec", "__child"}, args...)...)
 
 	c.SysProcAttr = &syscall.SysProcAttr{
 		Cloneflags: syscall.CLONE_NEWUTS | syscall.CLONE_NEWPID | syscall.CLONE_NEWNS,
@@ -45,16 +46,7 @@ func runContainedCmd(args []string) error {
 	c.Stdout = os.Stdout
 	c.Stderr = os.Stderr
 
-	if err := c.Run(); err != nil {
-		fmt.Printf("Command exited non-zero, not rebuilding/updating VNFS image\n")
-		// defer is not called before os.Exit(0)
-		err = os.RemoveAll(tempDir)
-		if err != nil {
-			wwlog.Warn("Couldn't remove temp dir for ephermal mounts:", err)
-		}
-		os.Exit(0)
-	}
-	return nil
+	return c.Run()
 }
 
 func CobraRunE(cmd *cobra.Command, args []string) error {

internal/app/wwctl/container/exec/root.go

@@ -25,17 +25,17 @@ var (
 		},
 		FParseErrWhitelist: cobra.FParseErrWhitelist{UnknownFlags: true},
 	}
-	SyncUser bool
-	binds    []string
-	tempDir  string
-	nodeName string
+	SyncUser   bool
+	binds      []string
+	overlayDir string
+	nodeName   string
 )
 
 func init() {
 	baseCmd.AddCommand(child.GetCommand())
 	baseCmd.PersistentFlags().StringArrayVarP(&binds, "bind", "b", []string{}, "Bind a local path into the container (must exist)")
 	baseCmd.PersistentFlags().BoolVar(&SyncUser, "syncuser", false, "Synchronize UIDs/GIDs from host to container")
-	baseCmd.PersistentFlags().StringVar(&tempDir, "tempdir", "", "Use tempdir for constructing the overlay fs (only used if mount points don't exist in container)")
+	baseCmd.PersistentFlags().StringVar(&overlayDir, "overlaydir", "", "Use tempdir for constructing the overlay fs (only used if mount points don't exist in container)")
 	baseCmd.PersistentFlags().StringVarP(&nodeName, "node", "n", "", "Create a read only view of the container for the given node")
 }