Return correct name for imported host files

Implement PrependPath() in host.filesystem to correctly format
name for host files.

Updates #1672

PiperOrigin-RevId: 309959135

2 files changed, 6 insertions, 8 deletions

diff --git a/pkg/sentry/fsimpl/kernfs/kernfs.go b/pkg/sentry/fsimpl/kernfs/kernfs.go
index 732837933..a83151ad3 100644
--- a/pkg/sentry/fsimpl/kernfs/kernfs.go
+++ b/pkg/sentry/fsimpl/kernfs/kernfs.go
@@ -132,13 +132,6 @@ func (fs *Filesystem) processDeferredDecRefsLocked() {
 	fs.droppedDentriesMu.Unlock()
 }
 
-// Init initializes a kernfs filesystem. This should be called from during
-// vfs.FilesystemType.NewFilesystem for the concrete filesystem embedding
-// kernfs.
-func (fs *Filesystem) Init(vfsObj *vfs.VirtualFilesystem, fsType vfs.FilesystemType) {
-	fs.vfsfs.Init(vfsObj, fsType, fs)
-}
-
 // VFSFilesystem returns the generic vfs filesystem object.
 func (fs *Filesystem) VFSFilesystem() *vfs.Filesystem {
 	return &fs.vfsfs
@@ -261,6 +254,11 @@ func (d *Dentry) insertChildLocked(name string, child *Dentry) {
 	d.children[name] = child
 }
 
+// Inode returns the dentry's inode.
+func (d *Dentry) Inode() Inode {
+	return d.inode
+}
+
 // The Inode interface maps filesystem-level operations that operate on paths to
 // equivalent operations on specific filesystem nodes.
 //
diff --git a/pkg/sentry/fsimpl/kernfs/kernfs_test.go b/pkg/sentry/fsimpl/kernfs/kernfs_test.go
index a9f671bc8..1c5d3e7e7 100644
--- a/pkg/sentry/fsimpl/kernfs/kernfs_test.go
+++ b/pkg/sentry/fsimpl/kernfs/kernfs_test.go
@@ -195,7 +195,7 @@ func (fsType) Name() string {
 
 func (fst fsType) GetFilesystem(ctx context.Context, vfsObj *vfs.VirtualFilesystem, creds *auth.Credentials, source string, opt vfs.GetFilesystemOptions) (*vfs.Filesystem, *vfs.Dentry, error) {
 	fs := &filesystem{}
-	fs.Init(vfsObj, &fst)
+	fs.VFSFilesystem().Init(vfsObj, &fst, fs)
 	root := fst.rootFn(creds, fs)
 	return fs.VFSFilesystem(), root.VFSDentry(), nil
 }