TOCTTOU in File::Path::rmtree() Version 2.12

• Internal subroutine _rmtree() underpins all 3 interfaces

        my ( $ldev, $lino, $perm ) = ( lstat $root )[ 0, 1, 2 ]
          or next ROOT_DIR;

• First time through, $root is a cleaned-up file path

• But _rmtree() is going to call itself recursively

  • So next time through, it may be a simple filename

• Use lstat rather than stat to account for possibility that $root is symlink

  • If it's a symlink, we want information about the symlink rather than its target