07af2808d5 (b/239632964) added
security policy support for /system_ext/bin/convert_to_ext4.sh.
This shell script converts f2fs filesystems into ext4 filesystems
on debuggable builds (userdebug or eng) only. Ever since 2022,
the security policy for this shell script has been in permissive
mode, meaning no SELinux rules were being enforced.
# convert-to-ext4-sh.te
permissive convert-to-ext4-sh;
In the intervening 2 years, there has been no attempt to move
this domain into enforcing mode. And by now, this script has
likely served its purpose, by converting f2fs /persist filesystems
on engineering builds to ext4, and is probably no longer needed.
This change eliminates the use of the unenforced convert-to-ext4-sh
security domain, preferring instead to use the "su" security domain.
Like convert-to-ext4-sh, the su security domain enforces no rules
on debuggable builds, and is equivalent to traditional root on
desktop Linux systems, or running /system/xbin/su. This change
eliminates unnecessary technical complexity, and unblocks other
hardening changes, such as WIP commit
https://android-review.googlesource.com/c/platform/system/sepolicy/+/3308856
Moving from one permissive domain ("convert-to-ext4-sh") to another
permissive domain ("su") should be a no-op from a security and
functionality perspective.
Test: compiles and builds, passes treehugger.
Bug: 239632964
Change-Id: Ifd628310a923926d1a57b568c7703cb857f0871b
588e82af38