Revise policy, to allow init and system_server to configure,
clear, and read kernel trace events. This will enable us to
debug certain WiFi failures.

Note that system_server is restricted to only accessing
a wifi-specific trace instance. (Hence, system_server is
not allowed to interfere with atrace.) Moreover, even for
the wifi trace instance, system_server is granted limited
permissions. (system_server can not, e.g., change which
events are traced.)

Note also that init and system_server are only granted these
powers on userdebug or eng builds.

The init.te and system_server.te changes resolve the
following denials:

// Denials when wifi-events.rc configures tracing
{ write } for pid=1 comm="init" name="instances" dev="debugfs" ino=755 scontext=u:r:init:s0 tcontext=u:object_r:debugfs_tracing_instances:s0 tclass=dir permissive=1
{ add_name } for pid=1 comm="init" name="wifi" scontext=u:r:init:s0 tcontext=u:object_r:debugfs_tracing_instances:s0 tclass=dir permissive=1
{ create } for pid=1 comm="init" name="wifi" scontext=u:r:init:s0 tcontext=u:object_r:debugfs_tracing_instances:s0 tclass=dir permissive=1
{ write } for pid=1 comm="init" name="tracing_on" dev="debugfs" ino=18067 scontext=u:r:init:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ write } for pid=1 comm="init" name="buffer_size_kb" dev="debugfs" ino=18061 scontext=u:r:init:s0 tcontext=u:object_r:debugfs_tracing_instances:s0 tclass=file permissive=1

// Denials when system_server sets up fail-safe
// (auto-terminate tracing if system_server dies)
{ search } for pid=882 comm="system_server" name="instances" dev="debugfs" ino=755 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_tracing_instances:s0 tclass=dir permissive=1
{ read } for pid=882 comm="system_server" name="free_buffer" dev="debugfs" ino=18063 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ open } for pid=882 comm="system_server" path="/sys/kernel/debug/tracing/instances/wifi/free_buffer" dev="debugfs" ino=18063 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ getattr } for pid=882 comm="system_server" path="/sys/kernel/debug/tracing/instances/wifi/free_buffer" dev="debugfs" ino=18063 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1

// Denials when system_server toggles tracing on or off
// (WifiStateMachine is a thread in system_server)
{ search } for pid=989 comm="WifiStateMachin" name="instances" dev="debugfs" ino=755 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_tracing_instances:s0 tclass=dir permissive=1
{ write } for pid=989 comm="WifiStateMachin" name="tracing_on" dev="debugfs" ino=18067 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ open } for pid=989 comm="WifiStateMachin" path="/sys/kernel/debug/tracing/instances/wifi/tracing_on" dev="debugfs" ino=18067 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ getattr } for pid=989 comm="WifiStateMachin" path="/sys/kernel/debug/tracing/instances/wifi/tracing_on" dev="debugfs" ino=18067 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ write } for pid=989 comm="WifiStateMachin" name="tracing_on" dev="debugfs" ino=18067 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ open } for pid=989 comm="WifiStateMachin" path="/sys/kernel/debug/tracing/instances/wifi/tracing_on" dev="debugfs" ino=18067 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ getattr } for pid=989 comm="WifiStateMachin" path="/sys/kernel/debug/tracing/instances/wifi/tracing_on" dev="debugfs" ino=18067 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1

// Denials when system_server reads the event trace
// (This happens in response to a dumpsys request)
{ search } for pid=3537 comm="Binder:882_B" name="instances" dev="debugfs" ino=755 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_tracing_instances:s0 tclass=dir permissive=1
{ read } for pid=3537 comm="Binder:882_B" name="trace" dev="debugfs" ino=18059 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ open } for pid=3537 comm="Binder:882_B" path="/sys/kernel/debug/tracing/instances/wifi/trace" dev="debugfs" ino=18059 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ getattr } for pid=3537 comm="Binder:882_B" path="/sys/kernel/debug/tracing/instances/wifi/trace" dev="debugfs" ino=18059 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1
{ write } for pid=3537 comm="Binder:882_B" name="trace" dev="debugfs" ino=18059 scontext=u:r:system_server:s0 tcontext=u:object_r:debugfs_wifi_tracing:s0 tclass=file permissive=1

Bug: 27254565
Test: manual
Manual test:
- Build this CL along with CL:322337
- Verify that system boots, and that we can connect to GoogleGuest.
  (Testing of actual trace functionality with require some more
  patches in frameworks/opt/net/wifi.)
$ adb root && adb shell dmesg | egrep 'avc: denied.+debugfs'

Change-Id: Ib6eb4116549277f85bd510d25fb30200f1752f4d

It seems likely that there is no reason to keep around a number of
devices that are configured to be included into the pixel kernels. Init
and ueventd should be the only processes with r/w access to these
devices, so auditallow rules have been added to ensure that they aren't
actually used.

/dev/keychord was given its own type since it's one of the few character
devices that's actually legitimately used and would cause log spam in
the auditallow otherwise.

Bug: 33347297
Test: The phone boots without any apparent log spam.

Change-Id: I3dd9557df8a9218b8c802e33ff549d15849216fb

Allow init to send userspace generated SELinux denials to the kernel
audit subsystem.

Test: "setprop asdf asdf" from the unprivileged adb shell user
      generated an SELinux denial processed by logd.
Bug: 27878170
Change-Id: I0ecd0601408bbda8227802c13689f98e507282d1

- transition to logpersist from init
- sort some overlapping negative references
- intention is to allow logpersist to be used by vendor
  userdebug logging

Test: gTest liblog-unit-tests, logd-unit-tests & logcat-unit-tests
Bug: 30566487
Change-Id: I7806f5a2548cbe0c1f257a0ba2855f2eb69d8e7c

init switch from a setcon() based transition to an exec() based
transition in bug 19702273. Fixup stale comment.

Test: comment only change. Policy compiles.
Bug: 19702273
Change-Id: I6e1b4b3680193453adafa8952a7ea343d2977505

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

Fixes: 32061937
Test: install/uninstall and verified no denials
Change-Id: I487727b6b32b1a0fb06ce66ed6dd69db43c8d536

This is required for https://android-review.googlesource.com/#/c/295748
so that init can drop the capability bounding set for services.

Bug: 32438163
Test: With 295748 and a test service using ambient capabilities.
Change-Id: I57788517cfe2ef0e7a2f1dfab94d0cb967ede065

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

(cherry picked from commit d3edd6b5)

Bug: 29278988
Change-Id: I199572377a6b5c33116c718a545159ddcf50df30

Remove the ioctl permission for most socket types. For others, such as
tcp/udp/rawip/unix_dgram/unix_stream set a default unprivileged whitelist
that individual domains may extend (except where neverallowed like
untrusted_app). Enforce via a neverallowxperm rule.

Change-Id: I15548d830f8eff1fd4d64005c5769ca2be8d4ffe

Grant permissions observed.

Bug: 28760354
Change-Id: Ie63cda709319bbf635ef7bffbba3477c2cccc11b

Bug: http://b/29622562
Change-Id: I21bc79f31ffd0b002b4a25d3ceefaf12f42f05c4

Grant permissions observed.

(cherry picked from commit 9c820a11)

Merged-in: Ifdead51f873eb587556309c48fb84ff1542ae303
Bug: 28760354
Change-Id: Ifdead51f873eb587556309c48fb84ff1542ae303

Specifically we need init to relabel (/dev/device-mapper, /dev/block/dm-?)
and other files in /dev/block/* from tmpfs to dm_device and block_device
respectively.

BUG=27805372

Change-Id: I16af6e803f8e4150481137aba24d5406872f9c62

Bug: http://b/30699558
Change-Id: Id9b213967ab290f45d1b8a5ab6712845ac9a0b69
Merged-In: Id9b213967ab290f45d1b8a5ab6712845ac9a0b69

These APIs expose sensitive information via timing side channels. This
leaves access via the adb shell intact along with the current uses by
dumpstate, init and system_server.

The /proc/interrupts and /proc/stat files were covered in this paper:

https://www.lightbluetouchpaper.org/2016/07/29/yet-another-android-side-channel/

The /proc/softirqs, /proc/timer_list and /proc/timer_stats files are
also relevant.

Access to /proc has been greatly restricted since then, with untrusted
apps no longer having direct access to these, but stricter restrictions
beyond that would be quite useful.

Change-Id: Ibed16674856569d26517e5729f0f194b830cfedd

Change-Id: I4c318efba76e61b6ab0be9491c352f281b1c2bff
Bug: 19160983

Since there is "write /proc/sys/vm/overcommit_memory 1" line in init.rc

Change-Id: I5899d2802e7fa56b438a06d4cadb4eb6827bfe16
Signed-off-by: Yongqin Liu <yongqin.liu@linaro.org>

Bug: 29278988
Change-Id: I199572377a6b5c33116c718a545159ddcf50df30

Since kernel 4.1 ftrace is supported as a new separate filesystem. It
gets automatically mounted by the kernel under the old path
/sys/kernel/debug/tracing. Because it lives now on a separate device
some sepolicy rules need to be updated. This patch is doing that. Most
of the rules are created based on a conversation happened on the SELinux
Android mailing list:

http://comments.gmane.org/gmane.comp.security.seandroid/2799



Note, that this also needs 3a343a1 from the 4.4 branch in kernel/common.
Also note that when tracefs is auto mounted by the kernel, the kernel
does not use the "mode" parameter specified to mount debugfs for
tracefs. So an extra line like

   chmod 0755 /sys/kernel/debug/tracing

is necessary in init.${ro.hardware}.rc after debugfs was mounted.

Signed-off-by: Christian Poetzsch <christian.potzsch@imgtec.com>

(cherry picked from commit 4dafa72a)

Change-Id: I75738c756b49da4ac109ae442ee37c1e2844ff0a

Since kernel 4.1 ftrace is supported as a new separate filesystem. It
gets automatically mounted by the kernel under the old path
/sys/kernel/debug/tracing. Because it lives now on a separate device
some sepolicy rules need to be updated. This patch is doing that. Most
of the rules are created based on a conversation happened on the SELinux
Android mailing list:

http://comments.gmane.org/gmane.comp.security.seandroid/2799



Note, that this also needs 3a343a1 from the 4.4 branch in kernel/common.
Also note that when tracefs is auto mounted by the kernel, the kernel
does not use the "mode" parameter specified to mount debugfs for
tracefs. So an extra line like

   chmod 0755 /sys/kernel/debug/tracing

is necessary in init.${ro.hardware}.rc after debugfs was mounted.

Change-Id: I60fb7a90e24628e0370c3bca57644451fce5646d
Signed-off-by: Christian Poetzsch <christian.potzsch@imgtec.com>

avc: denied { read } for name="device" dev="sysfs" ino=36099 scontext=u:r:init:s0 tcontext=u:object_r:sysfs_rmtfs:s0 tclass=lnk_file

init is already allowed to read directories, this is an obvious omission.

Change-Id: I5131a84bb67e73aaed235c3cbab95c365eaaa2f0

Bug: 27176738
Change-Id: Ib52bb94973d20591dd440cea42aadfa53d476848

Change-Id: Idaf59ab51f7873d4d75969c5f4e62b5fbf608ef5
Signed-off-by: William Roberts <william.c.roberts@intel.com>

(cherry pick from commit 6937aa93)

Followup to 121f5bfd.

Move misc_logd_file neverallow rule from domain.te to logd.te,
since the goal of the neverallow rule is to protect logd / logpersist
files from other processes.

Switch the misc_logd_file neverallow rule from using "rw_file_perms"
to "no_rw_file_perms". The latter covers more cases of file
modifications.

Add more neverallow rules covering misc_logd_file directories.

Instead of using not_userdebug_nor_eng(), modify the rules to be
consistent with other highly constrained file types such as
keystore_data_file or vold_data_file. See, for example,
https://android-review.googlesource.com/144768

To see the net effect of this change, you can use the following
command line:

  sesearch --allow -t misc_logd_file -c file,dir,lnk_file \
  out/target/product/bullhead/root/sepolicy

Before this change:

  # userdebug builds
  allow init misc_logd_file:dir { search setattr read create getattr write relabelfrom ioctl rmdir remove_name relabelto open add_name };
  allow init misc_logd_file:file { setattr read create write relabelfrom getattr relabelto unlink open };
  allow init misc_logd_file:lnk_file { setattr relabelfrom create getattr relabelto unlink };
  allow logd misc_logd_file:dir { search read lock getattr write ioctl remove_name open add_name };
  allow logd misc_logd_file:file { rename setattr read lock create getattr write ioctl unlink open append };
  allow shell misc_logd_file:dir { search read lock getattr ioctl open };
  allow shell misc_logd_file:file { read lock ioctl open getattr };

  # user builds
  allow init misc_logd_file:dir { search setattr read create getattr write relabelfrom ioctl rmdir remove_name relabelto open add_name };
  allow init misc_logd_file:file relabelto;
  allow init misc_logd_file:lnk_file { setattr relabelfrom create getattr relabelto unlink };

After this change:

  # userdebug builds
  allow init misc_logd_file:dir { search setattr read create getattr ioctl relabelto open };
  allow init misc_logd_file:file { relabelto getattr };
  allow init misc_logd_file:lnk_file relabelto;
  allow logd misc_logd_file:dir { search read lock getattr write ioctl remove_name open add_name };
  allow logd misc_logd_file:file { rename setattr read lock create getattr write ioctl unlink open append };
  allow shell misc_logd_file:dir { search read lock getattr ioctl open };
  allow shell misc_logd_file:file { read lock ioctl open getattr };

  # user builds
  allow init misc_logd_file:dir { search setattr read create getattr ioctl relabelto open };
  allow init misc_logd_file:file { relabelto getattr };
  allow init misc_logd_file:lnk_file relabelto;

Change-Id: I0b00215049ad83182f458b4b9e258289c5144479
Bug: 27965066

Some of the init allow rules were well passed 100 characters and
were difficult to read. Format them to use the one-per-line
set subtraction format as seen in other locations within sepolicy.

Change-Id: Ifeeb3a8a81c4c19bfb1e56e7f2493f817e896eaf
Signed-off-by: William Roberts <william.c.roberts@intel.com>

Followup to 121f5bfd.

Move misc_logd_file neverallow rule from domain.te to logd.te,
since the goal of the neverallow rule is to protect logd / logpersist
files from other processes.

Switch the misc_logd_file neverallow rule from using "rw_file_perms"
to "no_rw_file_perms". The latter covers more cases of file
modifications.

Add more neverallow rules covering misc_logd_file directories.

Instead of using not_userdebug_nor_eng(), modify the rules to be
consistent with other highly constrained file types such as
keystore_data_file or vold_data_file. See, for example,
https://android-review.googlesource.com/144768

To see the net effect of this change, you can use the following
command line:

  sesearch --allow -t misc_logd_file -c file,dir,lnk_file \
  out/target/product/bullhead/root/sepolicy

Before this change:

  # userdebug builds
  allow init misc_logd_file:dir { search setattr read create getattr write relabelfrom ioctl rmdir remove_name relabelto open add_name };
  allow init misc_logd_file:file { setattr read create write relabelfrom getattr relabelto unlink open };
  allow init misc_logd_file:lnk_file { setattr relabelfrom create getattr relabelto unlink };
  allow logd misc_logd_file:dir { search read lock getattr write ioctl remove_name open add_name };
  allow logd misc_logd_file:file { rename setattr read lock create getattr write ioctl unlink open append };
  allow shell misc_logd_file:dir { search read lock getattr ioctl open };
  allow shell misc_logd_file:file { read lock ioctl open getattr };

  # user builds
  allow init misc_logd_file:dir { search setattr read create getattr write relabelfrom ioctl rmdir remove_name relabelto open add_name };
  allow init misc_logd_file:file relabelto;
  allow init misc_logd_file:lnk_file { setattr relabelfrom create getattr relabelto unlink };

After this change:

  # userdebug builds
  allow init misc_logd_file:dir { search setattr read create getattr ioctl relabelto open };
  allow init misc_logd_file:file { relabelto getattr };
  allow init misc_logd_file:lnk_file relabelto;
  allow logd misc_logd_file:dir { search read lock getattr write ioctl remove_name open add_name };
  allow logd misc_logd_file:file { rename setattr read lock create getattr write ioctl unlink open append };
  allow shell misc_logd_file:dir { search read lock getattr ioctl open };
  allow shell misc_logd_file:file { read lock ioctl open getattr };

  # user builds
  allow init misc_logd_file:dir { search setattr read create getattr ioctl relabelto open };
  allow init misc_logd_file:file { relabelto getattr };
  allow init misc_logd_file:lnk_file relabelto;

Change-Id: I0b00215049ad83182f458b4b9e258289c5144479

(cherry pick from commit 121f5bfd)

03-25 09:31:22.996     1     1 W init    : type=1400 audit(0.0:8): \
  avc: denied { getattr } for path="/data/misc/logd/logcat.052" \
  dev="dm-2" ino=124778 scontext=u:r:init:s0 \
  tcontext=u:object_r:misc_logd_file:s0 tclass=file permissive=0
. . .

Introduced a new macro not_userdebug_nor_eng()

Change-Id: I9c3a952c265cac096342493598fff7d41604ca45

03-25 09:31:22.996     1     1 W init    : type=1400 audit(0.0:8): \
  avc: denied { getattr } for path="/data/misc/logd/logcat.052" \
  dev="dm-2" ino=124778 scontext=u:r:init:s0 \
  tcontext=u:object_r:misc_logd_file:s0 tclass=file permissive=0
. . .

Introduced a new macro not_userdebug_nor_eng()

Change-Id: I9c3a952c265cac096342493598fff7d41604ca45

Remove references to /data/security and the corresponding
type securitly_file.

Bug: 26544104
Change-Id: Iac00c293daa6b781a24c2bd4c12168dfb1cceac6

Change-Id: I4c318efba76e61b6ab0be9491c352f281b1c2bff
Bug: 19160983

When using the A/B updater, a device specific hook is sometimes needed
to run after the new partitions are updated but before rebooting into
the new image. This hook is referred to throughout the code as the
"postinstall" step.

This patch creates a new execution domain "postinstall" which
update_engine will use to run said hook. Since the hook needs to run
from the new image (namelly, slot "B"), update_engine needs to
temporarly mount this B partition into /postinstall and then run a
program from there.

Since the new program in B runs from the old execution context in A, we
can't rely on the labels set in the xattr in the new filesystem to
enforce the policies baked into the old running image. Instead, when
temporarily mounting the new filesystem in update_engine, we override
all the new file attributes with the new postinstall_file type by
passing "context=u:object_r:postinstall_file:s0" to the mount syscall.
This allows us to set new rules specific to the postinstall environment
that are consistent with the rules in the old system.

Bug: 27177071
TEST=Deployed a payload with a trivial postinstall script to edison-eng.

(cherry picked from commit 6cb2c893)

Change-Id: I49a529eecf1ef0524819470876ef7c8c2659c7ef

When using the A/B updater, a device specific hook is sometimes needed
to run after the new partitions are updated but before rebooting into
the new image. This hook is referred to throughout the code as the
"postinstall" step.

This patch creates a new execution domain "postinstall" which
update_engine will use to run said hook. Since the hook needs to run
from the new image (namelly, slot "B"), update_engine needs to
temporarly mount this B partition into /postinstall and then run a
program from there.

Since the new program in B runs from the old execution context in A, we
can't rely on the labels set in the xattr in the new filesystem to
enforce the policies baked into the old running image. Instead, when
temporarily mounting the new filesystem in update_engine, we override
all the new file attributes with the new postinstall_file type by
passing "context=u:object_r:postinstall_file:s0" to the mount syscall.
This allows us to set new rules specific to the postinstall environment
that are consistent with the rules in the old system.

Bug: 27177071
TEST=Deployed a payload with a trivial postinstall script to edison-eng.

Change-Id: Ib06fab92afb45edaec3c9c9872304dc9386151b4

Since linux 3.18, commit 68c4a4f8abc60c9440ede9cd123d48b78325f7a3 has
been integrated and requires syslog_read capability a process accessing
console-ramoops file.

sepolicy must be adapted to this new requirement.

Change-Id: Ib4032a6bd96b1828a0154edc8fb510e3c1d3bdc2
Signed-off-by: Sylvain Chouleur <sylvain.chouleur@intel.com>

This will allow init to terminate services cleanly (SIGTERM, wait,
SIGKILL) when needed.

Bug: 26216447
Test: manual: init is able to send a SIGTERM signal without denials.

Change-Id: Id2471ca08c0b011be64a36956628e965bc999bc6

Address following denials:
avc: denied { getattr } for path="/sys/devices/virtual/block/zram0/disksize" dev="sysfs" ino=14958 scontext=u:r:init:s0 tcontext=u:object_r:sysfs_zram:s0 tclass=file permissive=0
avc: denied { search } for name="zram0" dev="sysfs" ino=14903 scontext=u:r:system_server:s0 tcontext=u:object_r:sysfs_zram:s0 tclass=dir permissive=0
avc: denied { read } for name="mem_used_total" dev="sysfs" ino=14970 scontext=u:r:system_server:s0 tcontext=u:object_r:sysfs_zram:s0 tclass=file permissive=0
avc: denied { write } for name="uevent" dev="sysfs" ino=14904 scontext=u:r:ueventd:s0 tcontext=u:object_r:sysfs_zram:s0 tclass=file permissive=0
avc: denied { open } for path="/sys/devices/virtual/block/zram0/uevent" dev="sysfs" ino=14904 scontext=u:r:ueventd:s0 tcontext=u:object_r:sysfs_zram:s0 tclass=file permissive=0
avc: denied { read } for pid=348 comm="vold" name="zram0" dev="sysfs" ino=15223 scontext=u:r:vold:s0 tcontext=u:object_r:sysfs_zram:s0 tclass=dir permissive=0
avc: denied { search } for pid=3494 comm="ContactsProvide" name="zram0"dev="sysfs" ino=15223 scontext=u:r:priv_app:s0:c512,c768 tcontext=u:object_r:sysfs_zram:s0 tclass=dir permissive=0

Bug: 22032619
Change-Id: I40cf918b7cafdba6cb3d42b04b1616a84e4ce158

Needed to disable tracing. See frameworks/native/cmds/atrace/atrace.rc

Also allow shell getattr access to the tracing file. That way
"ls -la" returns something meaningful.

Bug: 26217098
Change-Id: I4eee1aff1127db8945612133c8ae16c34cfbb786

Add initial support for labeling files on /sys/kernel/debug.
The kernel support was added in https://android-review.googlesource.com/122130
but the userspace portion of the change was never completed until now.

Start labeling the file /sys/kernel/debug/tracing/trace_marker . This
is the trace_marker file, which is written to by almost all processes
in Android. Allow global write access to this file.

This change should be submitted at the same time as the system/core
commit with the same Change-Id as this patch.

Change-Id: Id1d6a9ad6d0759d6de839458890e8cb24685db6d