Function check_fs_node_symlink_access 

pub fn check_fs_node_symlink_access(
    current_task: &CurrentTask,
    parent: &FsNode,
    name: &FsStr,
    old_path: &FsStr,
) -> Result<(), Errno>

Validate that current_task has permission to create a symlink to old_path in the parent directory. Corresponds to the inode_symlink() LSM hook.