drivers: enhance check for mount fs type

when checking that a mount has a specific file system type, also validate that it is different than its parent directory. This helps when using virtiofs as the underlying file system since the check used for fuse-overlayfs would fail since they both use FUSE. Signed-off-by: Giuseppe Scrivano <[email protected]>
containers · Jun 14, 2022 · f10e276 · f10e276
1 parent 8951d01
commit f10e276
Showing 1 changed file with 13 additions and 1 deletion.
diff --git a/drivers/driver_linux.go b/drivers/driver_linux.go
@@ -1,3 +1,4 @@
+//go:build linux
 // +build linux
 
 package graphdriver
@@ -168,5 +169,16 @@ func Mounted(fsType FsMagic, mountPath string) (bool, error) {
 	if err := unix.Statfs(mountPath, &buf); err != nil {
 		return false, err
 	}
-	return FsMagic(buf.Type) == fsType, nil
+	if FsMagic(buf.Type) != fsType {
+		return false, nil
+	}
+	// it is already the root
+	if mountPath == "/" {
+		return true, nil
+	}
+
+	if err := unix.Statfs(filepath.Dir(mountPath), &buf); err != nil {
+		return true, err
+	}
+	return FsMagic(buf.Type) != fsType, nil
 }