Vendor in latest opencontainers/selinux

This will now verify labels passed in by the user.
Will also prevent users from accidently relabeling their homedir.

podman run -ti -v ~/home/user:Z fedora sh

Is not a good idea.

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>

vendor/github.com/opencontainers/selinux/go-selinux/label/label.go

@@ -75,8 +75,8 @@ func ReleaseLabel(label string) error {
 
 // DupSecOpt takes a process label and returns security options that
 // can be used to set duplicate labels on future container processes
-func DupSecOpt(src string) []string {
-	return nil
+func DupSecOpt(src string) ([]string, error) {
+	return nil, nil
 }
 
 // DisableSecOpt returns a security opt that can disable labeling

vendor/github.com/opencontainers/selinux/go-selinux/label/label_selinux.go

@@ -4,6 +4,8 @@ package label
 
 import (
 	"fmt"
+	"os"
+	"os/user"
 	"strings"
 
 	"github.com/opencontainers/selinux/go-selinux"
@@ -35,8 +37,15 @@ func InitLabels(options []string) (plabel string, mlabel string, Err error) {
 				ReleaseLabel(mountLabel)
 			}
 		}()
-		pcon := selinux.NewContext(processLabel)
-		mcon := selinux.NewContext(mountLabel)
+		pcon, err := selinux.NewContext(processLabel)
+		if err != nil {
+			return "", "", err
+		}
+
+		mcon, err := selinux.NewContext(mountLabel)
+		if err != nil {
+			return "", "", err
+		}
 		for _, opt := range options {
 			if opt == "disable" {
 				return "", mountLabel, nil
@@ -146,13 +155,56 @@ func Relabel(path string, fileLabel string, shared bool) error {
 		return nil
 	}
 
-	exclude_paths := map[string]bool{"/": true, "/usr": true, "/etc": true, "/tmp": true, "/home": true, "/run": true, "/var": true, "/root": true}
+	exclude_paths := map[string]bool{
+		"/":           true,
+		"/bin":        true,
+		"/boot":       true,
+		"/dev":        true,
+		"/etc":        true,
+		"/etc/passwd": true,
+		"/etc/pki":    true,
+		"/etc/shadow": true,
+		"/home":       true,
+		"/lib":        true,
+		"/lib64":      true,
+		"/media":      true,
+		"/opt":        true,
+		"/proc":       true,
+		"/root":       true,
+		"/run":        true,
+		"/sbin":       true,
+		"/srv":        true,
+		"/sys":        true,
+		"/tmp":        true,
+		"/usr":        true,
+		"/var":        true,
+		"/var/lib":    true,
+		"/var/log":    true,
+	}
+
+	if home := os.Getenv("HOME"); home != "" {
+		exclude_paths[home] = true
+	}
+
+	if sudoUser := os.Getenv("SUDO_USER"); sudoUser != "" {
+		if usr, err := user.Lookup(sudoUser); err == nil {
+			exclude_paths[usr.HomeDir] = true
+		}
+	}
+
+	if path != "/" {
+		path = strings.TrimSuffix(path, "/")
+	}
 	if exclude_paths[path] {
 		return fmt.Errorf("SELinux relabeling of %s is not allowed", path)
 	}
 
 	if shared {
-		c := selinux.NewContext(fileLabel)
+		c, err := selinux.NewContext(fileLabel)
+		if err != nil {
+			return err
+		}
+
 		c["level"] = "s0"
 		fileLabel = c.Get()
 	}
@@ -195,7 +247,7 @@ func ReleaseLabel(label string) error {
 
 // DupSecOpt takes a process label and returns security options that
 // can be used to set duplicate labels on future container processes
-func DupSecOpt(src string) []string {
+func DupSecOpt(src string) ([]string, error) {
 	return selinux.DupSecOpt(src)
 }
 

vendor/github.com/opencontainers/selinux/go-selinux/selinux_linux.go

@@ -52,6 +52,8 @@ var (
 	ErrMCSAlreadyExists = errors.New("MCS label already exists")
 	// ErrEmptyPath is returned when an empty path has been specified.
 	ErrEmptyPath = errors.New("empty path")
+	// InvalidLabel is returned when an invalid label is specified.
+	InvalidLabel = errors.New("Invalid Label")
 
 	assignRegex = regexp.MustCompile(`^([^=]+)=(.*)$`)
 	roFileLabel string
@@ -405,11 +407,14 @@ func (c Context) Get() string {
 }
 
 // NewContext creates a new Context struct from the specified label
-func NewContext(label string) Context {
+func NewContext(label string) (Context, error) {
 	c := make(Context)
 
 	if len(label) != 0 {
 		con := strings.SplitN(label, ":", 4)
+		if len(con) < 3 {
+			return c, InvalidLabel
+		}
 		c["user"] = con[0]
 		c["role"] = con[1]
 		c["type"] = con[2]
@@ -417,7 +422,7 @@ func NewContext(label string) Context {
 			c["level"] = con[3]
 		}
 	}
-	return c
+	return c, nil
 }
 
 // ClearLabels clears all reserved labels
@@ -630,12 +635,12 @@ func ContainerLabels() (processLabel string, fileLabel string) {
 		roFileLabel = fileLabel
 	}
 exit:
-	scon := NewContext(processLabel)
+	scon, _ := NewContext(processLabel)
 	if scon["level"] != "" {
 		mcs := uniqMcs(1024)
 		scon["level"] = mcs
 		processLabel = scon.Get()
-		scon = NewContext(fileLabel)
+		scon, _ = NewContext(fileLabel)
 		scon["level"] = mcs
 		fileLabel = scon.Get()
 	}
@@ -661,8 +666,14 @@ func CopyLevel(src, dest string) (string, error) {
 	if err := SecurityCheckContext(dest); err != nil {
 		return "", err
 	}
-	scon := NewContext(src)
-	tcon := NewContext(dest)
+	scon, err := NewContext(src)
+	if err != nil {
+		return "", err
+	}
+	tcon, err := NewContext(dest)
+	if err != nil {
+		return "", err
+	}
 	mcsDelete(tcon["level"])
 	mcsAdd(scon["level"])
 	tcon["level"] = scon["level"]
@@ -714,15 +725,18 @@ func Chcon(fpath string, label string, recurse bool) error {
 
 // DupSecOpt takes an SELinux process label and returns security options that
 // can be used to set the SELinux Type and Level for future container processes.
-func DupSecOpt(src string) []string {
+func DupSecOpt(src string) ([]string, error) {
 	if src == "" {
-		return nil
+		return nil, nil
+	}
+	con, err := NewContext(src)
+	if err != nil {
+		return nil, err
 	}
-	con := NewContext(src)
 	if con["user"] == "" ||
 		con["role"] == "" ||
 		con["type"] == "" {
-		return nil
+		return nil, nil
 	}
 	dup := []string{"user:" + con["user"],
 		"role:" + con["role"],
@@ -733,7 +747,7 @@ func DupSecOpt(src string) []string {
 		dup = append(dup, "level:"+con["level"])
 	}
 
-	return dup
+	return dup, nil
 }
 
 // DisableSecOpt returns a security opt that can be used to disable SELinux

vendor/github.com/opencontainers/selinux/go-selinux/selinux_stub.go

@@ -115,9 +115,9 @@ func (c Context) Get() string {
 }
 
 // NewContext creates a new Context struct from the specified label
-func NewContext(label string) Context {
+func NewContext(label string) (Context, error) {
 	c := make(Context)
-	return c
+	return c, nil
 }
 
 // ClearLabels clears all reserved MLS/MCS levels
@@ -195,8 +195,8 @@ func Chcon(fpath string, label string, recurse bool) error {
 
 // DupSecOpt takes an SELinux process label and returns security options that
 // can be used to set the SELinux Type and Level for future container processes.
-func DupSecOpt(src string) []string {
-	return nil
+func DupSecOpt(src string) ([]string, error) {
+	return nil, nil
 }
 
 // DisableSecOpt returns a security opt that can be used to disable SELinux