Adding a neverallow rule to prevent renaming of device and char files
This neverallow addition addresses the renaming of files in exploits in
order to bypass denied permissions. An example of a similar use case of
using mv to bypass permission denials appeared in a recent project zero
ChromeOS exploit as one of the steps in the exploit chain.
https://googleprojectzero.blogspot.com/2016/12/chrome-os-exploit-one-byte-overflow-and.html
Additionally, vold and init both had permission sets that allowed them
to rename, but neither of them seem to need it. Therefore the rename
permission has also been removed from these two .te files.
Test: The device boots successfully
Change-Id: I07bbb58f058bf050f269b083e836c2c9a5bbad80
3 files changed