USB booting :: how to edit file permission in DSL

when i want to update my PC firmware it show libcrypto.so.0.9.6 cannot be open and no such file or directory. how to update this file inside DSL? how to enable read and write permission in /usr/lib?

File permissions do not apply to root. If you need to rename a system file, changing permissions is not required or recommended. Just rename as root:
sudo mv oldname newname

Also not wise to rename system files, as it will surely break something (or many things). Better idea is to create a symlink to the file:
sudo ln -s oldname newname

original here.