Add a compile time assertion that only authorized SELinux domains are
allowed to touch the metadata_block_device. This domain may be wiped at
will, and we want to ensure that we're not inadvertently destroying
other people's data.
Test: policy compiles.
Change-Id: I9854b527c3d83e17f717d6cc8a1c6b50e0e373b6
In order to support platform changes without simultaneous updates from
non-platform components, the platform and non-platform policies must be
split. In order to provide a guarantee that policy written for
non-platform objects continues to provide the same access, all types
exposed to non-platform policy are versioned by converting them and the
policy using them into attributes.
This change performs that split, the subsequent versioning and also
generates a mapping file to glue the different policy components
together.
Test: Device boots and runs.
Bug: 31369363
Change-Id: Ibfd3eb077bd9b8e2ff3b2e6a0ca87e44d78b1317
Broke the dragon build:
libsepol.report_failure: neverallow on line 304 of system/sepolicy/public/domain.te (or line 8638 of policy.conf) violated by allow kernel device:chr_file { create setattr };
libsepol.check_assertions: 1 neverallow failures occurred
Error while expanding policy
This reverts commit ed0b4eb366.
Change-Id: I5d55ab59ed72ce7c19a10ddbb374f9f3b3fae4fd
By default, files created in /dev are labeled with the "device" label
unless a different label has been assigned. The direct use of this
generic label is discouraged (and in many cases neverallowed) because
rules involving this label tend to be overly broad and permissive.
Today, generically labeled character devices can only be opened, read,
or written to by init and ueventd.
$ sesearch --allow -t device -c chr_file -p open,read,write out/target/product/marlin/root/sepolicy
allow init device:chr_file { setattr read lock getattr write ioctl open append };
allow ueventd device:chr_file { read lock getattr write ioctl open append };
this is enforced by the following SELinux neverallow rule (compile time
assertion + CTS test):
neverallow { domain -init -ueventd } device:chr_file { open read write };
Start auditallowing ueventd access to /dev character device files with the
default SELinux label. This doesn't appear to be used, but let's prove it.
While ueventd is expected to create files in /dev, it has no need to open
most of the files it creates.
Note, however, that because ueventd has mknod + setfscreate permissions,
a malicious or compromised ueventd can always create a device node under
an incorrect label, and gain access that way.
The goal of this change is to prove that no process other than init are
accessing generically labeled files in /dev.
While I'm here, tighten up the compile time assertion for
device:chr_file to include more permissions.
Test: policy compiles + device boots with no granted messages.
Change-Id: Ic98b0ddc631b49b09e58698d9f40738ccedd1fd0
Only init and ueventd have any access to /dev/port, and neither should
have any use for it. As it stands, leaving port in just represents
additional attack surface with no useful functionality, so it should be
removed if possible, not only from Pixel devices, but from all Android
devices.
Test: The phone boots successfully
Bug:33301618
Change-Id: Iedc51590f1ffda02444587d647889ead9bdece3f
urandom_device and random_device have the exact same security
properties. Collapse them into one type.
Test: device boots and /dev/urandom is labeled correctly.
Change-Id: I12da30749291bc5e37d99bc9422bb86cb58cec41
The other domains either don't have the same backwards compatibility
issues (isolated_app) or are privileged components that are pretty much
part of the platform and can be expected to meet a higher standard.
It would be possible to expose a build option for disabling the ART JIT,
allowing conditional removal of execmem from some of these domains too
(ones not ever using the WebView, until that's always in isolated_app).
Bug: 20013628
Change-Id: Ic22513157fc8b958b2a3d60381be0c07b5252fa5
The webview_zygote is a new unprivileged zygote and has its own sockets for
listening to fork requests. However the webview_zygote does not run as root
(though it does require certain capabilities) and only allows dyntransition to
the isolated_app domain.
Test: m
Test: angler boots
Bug: 21643067
Change-Id: I89a72ffe6dcb983c4a44048518efd7efb7ed8e83
The underlying ioctl denial was fixed in device-specific policy.
It's not needed in core policy.
A search of SELinux denials shows no reported denials, other than the
ones showing up on marlin.
This reverts commit ec3285cde0.
(cherrypicked from commit 863ce3e7c7)
Test: AndroiTS GPS Test app shows GPS data, no SELinux denials.
Bug: 32290392
Change-Id: I1ba7bad43a2cdd7cdebbe1c8543a71eee765621d
Filesystem capabilities should only be set by the build tools
or by recovery during an update. Place a neverallow ensuring
this property.
Change-Id: I136c5cc16dff0c0faa3799d0ab5e29b43454a610
Signed-off-by: William Roberts <william.c.roberts@intel.com>
Divide policy into public and private components. This is the first
step in splitting the policy creation for platform and non-platform
policies. The policy in the public directory will be exported for use
in non-platform policy creation. Backwards compatibility with it will
be achieved by converting the exported policy into attribute-based
policy when included as part of the non-platform policy and a mapping
file will be maintained to be included with the platform policy that
maps exported attributes of previous versions to the current platform
version.
Eventually we would like to create a clear interface between the
platform and non-platform device components so that the exported policy,
and the need for attributes is minimal. For now, almost all types and
avrules are left in public.
Test: Tested by building policy and running on device.
Change-Id: Idef796c9ec169259787c3f9d8f423edf4ce27f8c
