system_file_type is a new attribute used to identify files which exist
on the /system partition. It's useful for allow rules in init, which are
based off of a blacklist of writable files. Additionally, it's useful
for constructing neverallow rules to prevent regressions.

Additionally, add commented out tests which enforce that all files on
the /system partition have the system_file_type attribute. These tests
will be uncommented in a future change after all the device-specific
policies are cleaned up.

Test: Device boots and no obvious problems.
Change-Id: Id9bae6625f042594c8eba74ca712abb09702c1e5

/system/usr/share/zoneinfo is currently labeled zoneinfo_data_file,
a label shared with /data/misc/zoneinfo. However, each of these
directory locations has different security characteristics. In
particular, the files in /system/usr/share/zoneinfo must never be
writable, whereas /data/misc/zoneinfo may be written to by system_server.
Reusing the same label hides these different security characteristics.

Create a separate label for /system/usr/share/zoneinfo.

Test: Device boots and no obvious problems.
Change-Id: I8cf16ff038b06b38f77388e546d9b7a6865f7879

Fixes:
avc: denied { read } for comm="init" name="linker_asan64" dev="sda22" ino=1833
scontext=u:r:init:s0 tcontext=u:object_r:system_linker_exec:s0 tclass=lnk_file
permissive=0

Bug: 116486312
Test: adb unroot && adb shell ls -l /system/bin/linker_asan
Change-Id: I754daaf3576e83d516cc9189b8be04dcc41bbc5c

Create a new service type buffer_hub_binder_service for
BufferHubBinderService and allow bufferhubd to publish the service.

Add the service to 26.0, 27.0 and 28.0 compat ignore files since the
service is not available in past versions.

Fixes: 116022258
Test: build passed

Change-Id: I5a21f00329ed474433d96c8d1ce32377f20cada3

Allow vold to run exFAT filesystem check.

Test: build, mount exFAT volume
Bug: 80202067
Change-Id: I68f3438de89246e806cebe483f37e31c68aaa3d7

Assert that only apps and installd may open private app files.

Remove "open" permission for mediaserver/vold and remove their
neverallow exemption.

Test: verify no related audit messages in the logs.
Test: build
Fixes: 80300620
Fixes: 80418809
Bug: 80190017
Change-Id: If0c1862a273af1fedd8898f334c9b0aa6b9be728

Bug: 111461540
Bug: 112570477

Test: builds
Change-Id: Icc68720ebe931c2d917703b2d34aa0f4eec3f549
Merged-In: Icc68720ebe931c2d917703b2d34aa0f4eec3f549

...to reflect that the HAL operates on storage devices,
not filesystem.

Bug: 111655771
Test: compiles
Change-Id: Ibb0572cb1878359e5944aa6711331f0c7993ba6e
Merged-In: Ibb0572cb1878359e5944aa6711331f0c7993ba6e

This change limits global access to /system files down to:
/system/bin/linker*
/system/lib[64]/*
/system/etc/ld.config*
/system/etc/seccomp_policy/*
/system/etc/security/cacerts/*
/system/usr/share/zoneinfo/*

Bug: 111243627
Test: boot device, browse internet without denials to system_* types.
Test: VtsHalDrmV1_{1, 0}TargetTest without denials
Change-Id: I69894b29733979c2bc944ac80229e84de5d519f4

kernel commit 2a4c22426955d4fc04069811997b7390c0fb858e (fs: switch order
of CAP_DAC_OVERRIDE and CAP_DAC_READ_SEARCH checks) swapped the order of
dac_override and dac_read_search checks.  Domains that have dac_override
will now generate spurious denials for dac_read_search unless they also
have that permission.  Since dac_override is a strict superset of
dac_read_search, grant dac_read_search to all domains that already have
dac_override to get rid of the denials.

Bug: 114280985
Bug: crbug.com/877588
Test: Booted on a device running 4.14.
Change-Id: I5c1c136b775cceeb7f170e139e8d4279e73267a4

This allows the trace producer daemon to snapshot counters at
high frequency in the trace. As usual for Perfetto, this data is
NOT made available to arbitrary apps but only to an extremely
limited subset of processes governed by selinux rules (currently
shell and statsd).

Bug: 115956288
Change-Id: I7e1bfda4b568b9bac9012b198ecbb998da4f773d

Test: Build.
Change-Id: I5c02916dfa3b2e8d5ba2bc586d05a69bd1f1254f
Merged-In: I150bc74b13a77f00a7e8b31a6c2edf9654bdbe59

Add additional compile time constraints on the ability to ptrace various
sensitive domains.

llkd: remove some domains which llkd should never ptrace, even on
debuggable builds, such as kernel threads and init.

crash_dump neverallows: Remove the ptrace neverallow checks because
it duplicates other neverallow assertions spread throughout the policy.

Test: policy compiles and device boots
Change-Id: Ia4240d1ce7143b983bb048e046bb4729d0af5a6e

Bug: 9496886
Bug: 109758967
Test: atest HostsideVpnTests
Change-Id: I1716d9c740b374b861e691b31ab271c681cf6bff

Test: manual test

BUG: b/112432890
Change-Id: If703cd25a2c0864ffd49bfdc83821fae291974b5

Test: comments only. Policy compiles.
Change-Id: Ic51533d37fff6c553950a122f33a48e3c119c67c

Currently, both untrusted apps and priv-apps use the SELinux file label
"app_data_file" for files in their /data/data directory. This is
problematic, as we really want different rules for such files. For
example, we may want to allow untrusted apps to load executable code
from priv-app directories, but disallow untrusted apps from loading
executable code from their own home directories.

Commit 23c9d91b introduced a new type
called privapp_data_file and added rules necessary to preserve
compatibility. However, that change did not relabel any existing files,
so effectively the change was a no-op.

This change performs the switch, relabeling priv-app's /data/data files
from app_data_file to privapp_data_file. Due to the compatibility rules
added in 23c9d91b, there should be no
noticeable effect from this change.

This change was originally submitted as
4df57822. However, it was reverted in
cdc6649a due to a different labeling
bug. That bug has been fixed, and we can reapply this change.

Test: Factory reset and boot - no problems on fresh install.
Test: Upgrade to new version and test. No compatibility problems on
      filesystem upgrade.
Bug: 112357170

Kernel commit 8a2af06415ef0fc922162503dd18da0d9be7771f (ashmem: switch
to ->read_iter) switched ashmem from using __vfs_read to vfs_iter_read
to read the backing shmem file.  Prior to this, reading from an ashmem
fd that was passed between processes didn't hit any permission checks;
now SELinux checks that the receiver can read from the creator's file
context.

Some apps receive buffers through ashmem from system_server, e.g., the
settings app reads battery stats from system_server through ashmem when
an app details page is opened.  Restore this ability by giving apps read
access to system_server_tmpfs.  system_server is still responsible for
creating and passing across the ashmem buffers, so this doesn't give
apps the ability to read anything system_server isn't willing to give
them.

Bug: 112987536
Bug: 111381531
Test: atest android.appsecurity.cts.PermissionsHostTest on kernel 4.14
Change-Id: Ice5e25f55bc409e91ad7e8c7ea8b28ae213191a3

Historically most uses of atrace happen via the shell domain.

There are two exceptions:
- boot tracing
- traced_probes

We need to get feature parity, so atrace has the same behavior
when is invoked either via shell or from its own domain (e.g.
via traced_probes that has an auto_trans rule into atrace on exec).
Atrace works by setting system properties to enable tracing from userspace
then poking all the binder services to read the system properties (see [1]) so
enabling the system_server category requires the ability to call binder
methods on the system_server.

For more use cases see b/113127224

[1]: https://android.googlesource.com/platform/frameworks/native/+/9ead54bed65d486fe435793cbe98ed8b4786f7be/cmds/atrace/atrace.cpp#545

Bug: 113127224
Test: Add an atrace category to the Perfetto config and confirm the data
shows up.

Change-Id: Id077eff960ffb1cdd7b0ce84b21ac9ef70444a4a

https://github.com/torvalds/linux/commit/af63f4193f9fbbbac50fc766417d74735afd87ef
allows a security policy writer to determine whether transitions under
nosuid / NO_NEW_PRIVS should be allowed or not.

Define these permissions, so that they're usable to policy writers.

This change is modeled after refpolicy
https://github.com/TresysTechnology/refpolicy/commit/1637a8b407c85f67f0b2ca5c6d852cef3c999087

Test: policy compiles and device boots
Test Note: Because this requires a newer kernel, full testing on such
   kernels could not be done.
Change-Id: I9866724b3b97adfc0cdef5aaba6de0ebbfbda72f

Access is deprecated for apps with targetSdkVersion=26+.

Test: build (neverallow rules are build time assertions)
Change-Id: I36480c38d45cf6bfb75f4988ffcefefc6b62d4b1

Test: Built and flashed an image.
Bug: 113651685
Change-Id: Ide239432ea8a5701d91c00edd06ad3e52560a3f7

Not needed for modern Android versions. These rules are really, really
old.

Test: "adb bugreport" continues to work
Test: Generating a bugreport via key combo continues to work.
Change-Id: Ibc1157fb36abd7fc701db3819474f25210a3cb5f

When /system/bin/crash_dump is executed from the su domain, do not
perform a domain transition. This allows processes run from that domain
to crash normally without SELinux interfering.

Bug: 114136122
Test: cferris: "This change works for me. I ran the crasher executable on
  /data, /data/nativetest, /data/nativetest64 (and even /data/local/tmp).
  All of them show that crash_dump can read the executables."
Change-Id: Ic135d61b11774acff37ebfb35831497cddbefdef

Bug: 109809543
Test: Build and boot with the new service in the internal branch.

Change-Id: Iaee365771c3e8e5b8f5f3b6112bbf902c6bb02bd

DropboxManager may pass FDs to any app with the READ_LOGS
permission which is available to all apps as a development
permission.

Test: atest CtsIncidentHostTestCases
Fixes: 111856304
Change-Id: I329e3125dab83de948b860061df9d232e31cb23e

llkd needs the ptrace capabilities and dac override to monitor for
live lock conditions on the stack dumps.

Test: compile
Bug: 33808187
Change-Id: Ibc1e4cc10395fa9685c4ef0ca214daf212a5e126

This is not needed and could conceivably be abused.

Test: Builds.
Bug: 110107376
Change-Id: I73f301439af435fe40b3902409964cdf6e2c7dd5

Bug: 72825012

Test: manual
Change-Id: I850c869cdc0ad8735800130bb4a8d67822197ff9

Remove permissions and add neverallow assertion.

(cherry picked from commit f1554f15)

Bug: 110107376
Test: kill -6 <components excluded from ptrace>
Change-Id: I2dc872f5c02749fbaf8ca6bc7e3e38404151442c

Also move statsd to /public/

Bug: 110538431
Test: manual testing
Change-Id: I58319e169eaab7d997ed3628c3c9709cf7bd0d4a

Bug: 111215474
Test: boots
Change-Id: I98955bcd02f643400c3eb97232467c09a2c5c1e5

Bug: 110887137
Test: Flash new system policy onto a device with vendor policy that uses
untrusted_app_visible_* attributes, and check that old and new attributes
are applied to exactly same types.
Change-Id: Ibee0ec645878fcc8c93cd0fbd169a8d45129d79e
Merged-In: Ibee0ec645878fcc8c93cd0fbd169a8d45129d79e
(cherry picked from commit 7abca51d)

commit 9b2e0cbe added a new
self:global_capability_class_set macro that covers both self:capability
and self:cap_userns.  Apply the new macro to various self:capability
references that have cropped up since then.

Bug: 112307595
Test: policy diff shows new rules are all cap_userns
Change-Id: I3eb38ef07532a8e693fd549dfdbc4a6df5329609

Bug: 78793464
Test: fastboot getvar partition-size:super

'super_block_device' corresponds to the super partition
required for flashing dynamic partitions.

Change-Id: I323634b6797ead7c5face117a7028bf9ab947aea

Attempting to reduce the number of different spellings we have for
"product services" partition in the codebase.

Bug: 112431447
Test: m
Change-Id: I1499c60e3d6c6c9fbe2e3f30f097f83b1e837c1c
Merged-In: I1499c60e3d6c6c9fbe2e3f30f097f83b1e837c1c

avc: denied { getattr } for comm="Binder:1231_1" path="/storage/emulated" dev="tmpfs" ino=72787 scontext=u:r:system_server:s0 tcontext=u:object_r:storage_stub_file:s0 tclass=dir

Bug: 112609936
Test: Built policy.
Change-Id: Ib772aca11bad4ba267de259be4ad065f228ef1df

Also allow adb and fastboot to talk to recovery
through recovery_socket. This enables changing
between modes with usb commands.

Test: No selinux denials
Bug: 78793464
Change-Id: I80c54d4eaf3b94a1fe26d2280af4e57cb1593790

This reverts commit 0fd3ed3b.

Reason for revert: Broke user builds.

Change-Id: If95f1a25d22425a5a2b68a02d1561352fb5a52f0

Also allow adb and fastboot to talk to recovery
through recovery_socket. This enables changing
between modes with usb commands.

Test: No selinux denials
Bug: 78793464
Change-Id: I1f97659736429fe961319c642f458c80f199ffb4