platform_system_sepolicy/prebuilts/api/31.0/public/fsck_untrusted.te
Inseob Kim 08d4c8fa6e Add fake 31.0 prebuilt
This commit adds fake 31.0 prebuilt. The prebuilt is based on AOSP
policy, but slightly modified so the set of types and attributes is a
subset of real 31.0 prebuilt (sc-dev policy).

Steps taken to make the fake prebuilt:

1) build plat_sepolicy.cil both on AOSP and sc-dev, with lunch target
aosp_arm64-eng.
2) diff both outputs to find out which types and attributes don't exist.
3) remove all relevant files and statements.

As a result, the following types are removed.

artd
artd_exec
artd_service
power_stats_service
transformer_service
virtualizationservice
virtualizationservice_data_file
virtualizationservice_exec

Bug: 189161483
Test: N/A, will do after adding 31.0 mapping files.
Change-Id: Ia957fc32b1838dae730d9dd7bd917d684d4a24cf
Merged-In: Ia4ea2999f4bc8ae80f13e51d99fba3e98e293447
2021-06-15 12:08:00 +00:00

49 lines
1.7 KiB
Text

# Any fsck program run on untrusted block devices
type fsck_untrusted, domain;
# Inherit and use pty created by android_fork_execvp_ext().
allow fsck_untrusted devpts:chr_file { read write ioctl getattr };
# Allow stdin/out back to vold
allow fsck_untrusted vold:fd use;
allow fsck_untrusted vold:fifo_file { read write getattr };
# Run fsck on vold block devices
allow fsck_untrusted block_device:dir search;
allow fsck_untrusted vold_device:blk_file rw_file_perms;
allow fsck_untrusted proc_mounts:file r_file_perms;
# To determine if it is safe to run fsck on a filesystem, e2fsck
# must first determine if the filesystem is mounted. To do that,
# e2fsck scans through /proc/mounts and collects all the mounted
# block devices. With that information, it runs stat() on each block
# device, comparing the major and minor numbers to the filesystem
# passed in on the command line. If there is a match, then the filesystem
# is currently mounted and running fsck is dangerous.
# Allow stat access to all block devices so that fsck can compare
# major/minor values.
allow fsck_untrusted dev_type:blk_file getattr;
###
### neverallow rules
###
# Untrusted fsck should never be run on block devices holding sensitive data
neverallow fsck_untrusted {
boot_block_device
frp_block_device
metadata_block_device
recovery_block_device
root_block_device
swap_block_device
system_block_device
userdata_block_device
cache_block_device
dm_device
}:blk_file no_rw_file_perms;
# Only allow entry from vold via fsck binaries
neverallow { domain -vold } fsck_untrusted:process transition;
neverallow * fsck_untrusted:process dyntransition;
neverallow fsck_untrusted { file_type fs_type -fsck_exec }:file entrypoint;