This has nothing to do with /lib/udev/devices/null - that should have 0600 permissions.
If you have this problem on EDGY, please open a new bug and provide the information requested (/var/log/udev and output of "udevtest /class/mem/null") -- /dev/null: Permission denied https://launchpad.net/bugs/63031 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs