Allow lmkd read access to /proc/meminfo for retrieving information
on memory state.

Bug: 75322373
Change-Id: I7cf685813a5a49893c8f9a6ac4b5f6619f3c18aa
Merged-In: I7cf685813a5a49893c8f9a6ac4b5f6619f3c18aa
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
(cherry picked from commit 76384b3e)

llkd needs the ability to forcibly crash the kernel if
cause is unlikely to result in an orderly shutdown. It
also needs to scan /proc/<pid> for additional process
information.

Test: lmkd_unit_test --gtest_filter=llkd.*
Bug: 33808187
Change-Id: I7f158a13814e79d5ec71fe90dbc7461abb521945

llkd needs the ability to forcibly crash the kernel if
cause is unlikely to result in an orderly shutdown. It
also needs to scan /proc/<pid> for additional process
information.

Test: lmkd_unit_test --gtest_filter=llkd.*
Bug: 33808187
Change-Id: I7f158a13814e79d5ec71fe90dbc7461abb521945

In kernel 4.7, the capability and capability2 classes were split apart
from cap_userns and cap2_userns (see kernel commit
8e4ff6f228e4722cac74db716e308d1da33d744f). Since then, Android cannot be
run in a container with SELinux in enforcing mode.

This change applies the existing capability rules to user namespaces as
well as the root namespace so that Android running in a container
behaves the same on pre- and post-4.7 kernels.

This is essentially:
  1. New global_capability_class_set and global_capability2_class_set
     that match capability+cap_userns and capability2+cap2_userns,
     respectively.
  2. s/self:capability/self:global_capability_class_set/g
  3. s/self:capability2/self:global_capability2_class_set/g
  4. Add cap_userns and cap2_userns to the existing capability_class_set
     so that it covers all capabilities.  This set was used by several
     neverallow and dontaudit rules, and I confirmed that the new
     classes are still appropriate.

Test: diff new policy against old and confirm that all new rules add
      only cap_userns or cap2_userns;
      Boot ARC++ on a device with the 4.12 kernel.
Bug: crbug.com/754831

Change-Id: I4007eb3a2ecd01b062c4c78d9afee71c530df95f

Bug: 65643247
Test: device boots without denials from lmkd
Change-Id: I6db8b52a4fb3edefbcbc87d6ca5f1b76162e9dce

Currently lmkd is not able to read memcg info. The mem/swap usage
info are used by lmkd to ugrade medium pressure events to critical
level.

Test: tested on gobo
Bug: 65180281
Change-Id: I19d0eb53d5e754c176ffeda1b5d07049e6af8570

Currently lmkd is not able to read memcg info. The mem/swap usage
info are used by lmkd to ugrade medium pressure events to critical
level.

Test: tested on gobo
Bug: 65180281
Change-Id: I19d0eb53d5e754c176ffeda1b5d07049e6af8570

Allow lmkd to access /dev/memcg once again.

Test: lmkd can access memcg
bug 36588803

Change-Id: I47b4e79260bcd2967d85d8151c83e624d432f409

This reverts commit 527f64e6.

Change-Id: Ibc48af53431a8f7c7211999dcb571f492fb5ddb4

Allow lmkd to access /dev/memcg once again.

Test: lmkd can access memcg
bug 36588803

Change-Id: Ia57dbbc3987d8858c932103c4e546cbb88893207

As of https://android-review.googlesource.com/324092, ephemeral_app is
now an appdomain, so places where both appdomain and ephemeral_app are
granted the same set of rules can be deleted.

Test: policy compiles.
Change-Id: Ideee710ea47af7303e5eb3af1331653afa698415

No denials showing up in collected audit logs.

Bug: 28760354
Test: Device boots
Test: No unexpected denials in denial collection logs.
Change-Id: I5a0d4f3c51d296bfa04e71fc226a01dcf5b5b508

Test: Builds and boots
Change-Id: I3db64e12f0390c6940f5745eae83ce7efa7d65a9

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

Change-Id: Ica9a16311075f5cc3744d0e0833ed876e201029f

avc: denied { search } for pid=394 comm="lmkd" name="lowmemorykiller" dev="sysfs" ino=7541 scontext=u:r:lmkd:s0 tcontext=u:object_r:sysfs_lowmemorykiller:s0 tclass=dir permissive=0

(Cherry picked from commit 30a3ee4c)

Bug: 29558514
Change-Id: Iaae907a92976af2a9dcb58be5643b8614dcde174

avc: denied { search } for pid=394 comm="lmkd" name="lowmemorykiller" dev="sysfs" ino=7541 scontext=u:r:lmkd:s0 tcontext=u:object_r:sysfs_lowmemorykiller:s0 tclass=dir permissive=0

Bug: 29558514
Change-Id: Iaae907a92976af2a9dcb58be5643b8614dcde174

Modify many "neverallow domain" rules to be "neverallow *" rules
instead. This will catch more SELinux policy bugs where a label
is assigned an irrelevant rule, as well as catch situations where
a domain attribute is not assigned to a process.

Change-Id: I5b83a2504c13b384f9dff616a70ca733b648ccdf

Change-Id: Ia90fb531cfd99d49d179921f041dd93c7325ad50

Motivation: Domain is overly permissive. Start removing permissions
from domain and assign them to the domain_deprecated attribute.
Domain_deprecated and domain can initially be assigned to all
domains. The goal is to not assign domain_deprecated to new domains
and to start removing domain_deprecated where it is not required or
reassigning the appropriate permissions to the inheriting domain
when necessary.

Bug: 25433265
Change-Id: I8b11cb137df7bdd382629c98d916a73fe276413c

dumpstate and lmkd need to act on apps running at any level.

Various file types need to be writable by apps running at any
level.

Change-Id: Idf574d96ba961cc110a48d0a00d30807df6777ba
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>

https://android-review.googlesource.com/94851 added an LD_PRELOAD
line to init.environ.rc.in. This has the effect of loading
libsigchain.so into every process' memory space, regardless of
whether it wants it or not.

For lmkd, it doesn't need libsigchain, so it doesn't make any sense
to load it and keep it locked in memory.

Disable noatsecure for lmkd. This sets AT_SECURE=1, which instructs the
linker to not honor security sensitive environment variables such
as LD_PRELOAD. This prevents libsigchain.so from being loaded into
lmkd's memory.

(cherry picked from commit 8a5b28d2)

Change-Id: I39baaf62058986d35ad43de708aaa3daf93b2df4

https://android-review.googlesource.com/94851 added an LD_PRELOAD
line to init.environ.rc.in. This has the effect of loading
libsigchain.so into every process' memory space, regardless of
whether it wants it or not.

For lmkd, it doesn't need libsigchain, so it doesn't make any sense
to load it and keep it locked in memory.

Disable noatsecure for lmkd. This sets AT_SECURE=1, which instructs the
linker to not honor security sensitive environment variables such
as LD_PRELOAD. This prevents libsigchain.so from being loaded into
lmkd's memory.

Change-Id: I6378ba28ff3a1077747fe87c080e1f9f7ca8132e

addresses the following denial:

  type=1400 audit(1.871:3): avc:  denied  { ipc_lock } for  pid=1406 comm="lmkd" capability=14  scontext=u:r:lmkd:s0 tcontext=u:r:lmkd:s0 tclass=capability

Bug: 16236289

(cherry picked from commit 6a1405d7)

Change-Id: I560f1e52eac9360d10d81fc8a9f60eba907a8466

addresses the following denial:

  type=1400 audit(1.871:3): avc:  denied  { ipc_lock } for  pid=1406 comm="lmkd" capability=14  scontext=u:r:lmkd:s0 tcontext=u:r:lmkd:s0 tclass=capability

Bug: 16236289
Change-Id: Id9923c16c6db026dd5d28996126f503c5c1d7c87

Addresses the following selinux denials:
type=1400 audit(1405383429.107:22): avc: denied { remove_name } for pid=137 comm="lmkd" name="uid_10060" dev="cgroup" ino=18368 scontext=u:r:lmkd:s0 tcontext=u:object_r:cgroup:s0 tclass=dir permissive=0
type=1400 audit(1405383794.109:6): avc: denied { sys_nice } for pid=1619 comm="lmkd" capability=23 scontext=u:r:lmkd:s0 tcontext=u:r:lmkd:s0 tclass=capability permissive=0

(cherry picked from commit 53297318)

Change-Id: I7b6e5a396bf345c4768defd7b39af2435631a35b

Addresses the following selinux denials:
type=1400 audit(1405383429.107:22): avc: denied { remove_name } for pid=137 comm="lmkd" name="uid_10060" dev="cgroup" ino=18368 scontext=u:r:lmkd:s0 tcontext=u:object_r:cgroup:s0 tclass=dir permissive=0
type=1400 audit(1405383794.109:6): avc: denied { sys_nice } for pid=1619 comm="lmkd" capability=23 scontext=u:r:lmkd:s0 tcontext=u:r:lmkd:s0 tclass=capability permissive=0

Change-Id: I7b6e5a396bf345c4768defd7b39af2435631a35b

The previous patch wasn't sufficient. Allow the kill signal.

Addresses the following denial:

<5>[  775.819223] type=1400 audit(1393978653.489:18): avc:  denied  { sigkill } for  pid=118 comm="lmkd" scontext=u:r:lmkd:s0 tcontext=u:r:untrusted_app:s0 tclass=process

Bug: 13084787
Change-Id: I6af1ed4343b590049809a59e4f2797f6049f12e4

lmkd needs the capability to kill processes.

Addresses the following denial:

<5>[12619.064604] type=1400 audit(1393540506.745:2565): avc:  denied  { kill } for  pid=116 comm="lmkd" capability=5  scontext=u:r:lmkd:s0 tcontext=u:r:lmkd:s0 tclass=capability

Addresses the following errors:

02-27 13:13:50.995   116   116 I lowmemorykiller: Killing 'com.google.android.deskclock' (7133), adj 15
02-27 13:13:50.995   116   116 I lowmemorykiller:    to free 33836kB because cache 118512kB is below limit 122880kB for oom_adj 15
02-27 13:13:50.995   116   116 I lowmemorykiller:    Free memory is -28472kB below reserved
02-27 13:13:50.995   116   116 E lowmemorykiller: kill(7133): errno=1

Change-Id: I7cca238610307aba9d77aa2e52a32ebd6aec3f3c

Addresses the following denial / error:

E/lowmemorykiller(  187): Error writing /proc/1148/oom_adj; errno=13

[  118.264668] type=1400 audit(947231128.209:140): avc:  denied { sys_resource } for  pid=187 comm="lmkd" capability=24 scontext=u:r:lmkd:s0 tcontext=u:r:lmkd:s0 tclass=capability

Change-Id: Ief2a7ead9cdd8a33e3add111ee99f7a29c12a3f2

Start enforcing SELinux rules for lmkd. Security policy
violations will return an error instead of being allowed.

Change-Id: I2bad2c2094d93ebbcb8ccc4b7f3369419004a3f0

* Allow writes to /proc/PID/oom_score_adj
* Allow writes to /sys/module/lowmemorykiller/*

Addresses the following denials:
<5>[    3.825371] type=1400 audit(9781555.430:5): avc:  denied  { write } for  pid=176 comm="lmkd" name="minfree" dev="sysfs" ino=6056 scontext=u:r:lmkd:s0 tcontext=u:object_r:sysfs:s0 tclass=file
<5>[   48.874747] type=1400 audit(9781600.639:16): avc:  denied  { search } for  pid=176 comm="lmkd" name="896" dev="proc" ino=9589 scontext=u:r:lmkd:s0 tcontext=u:r:system_server:s0 tclass=dir
<5>[   48.874889] type=1400 audit(9781600.639:17): avc:  denied  { dac_override } for  pid=176 comm="lmkd" capability=1  scontext=u:r:lmkd:s0 tcontext=u:r:lmkd:s0 tclass=capability
<5>[   48.874982] type=1400 audit(9781600.639:18): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=8942 scontext=u:r:lmkd:s0 tcontext=u:r:system_server:s0 tclass=file
<5>[   48.875075] type=1400 audit(9781600.639:19): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=8942 scontext=u:r:lmkd:s0 tcontext=u:r:system_server:s0 tclass=file
<5>[   49.409231] type=1400 audit(9781601.169:20): avc:  denied  { write } for  pid=176 comm="lmkd" name="minfree" dev="sysfs" ino=6056 scontext=u:r:lmkd:s0 tcontext=u:object_r:sysfs:s0 tclass=file
<5>[  209.081990] type=1400 audit(9781760.839:24): avc:  denied  { search } for  pid=176 comm="lmkd" name="1556" dev="proc" ino=10961 scontext=u:r:lmkd:s0 tcontext=u:r:platform_app:s0 tclass=dir
<5>[  209.082240] type=1400 audit(9781760.839:25): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11654 scontext=u:r:lmkd:s0 tcontext=u:r:platform_app:s0 tclass=file
<5>[  209.082498] type=1400 audit(9781760.839:26): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11654 scontext=u:r:lmkd:s0 tcontext=u:r:platform_app:s0 tclass=file
<5>[  209.119673] type=1400 audit(9781760.879:27): avc:  denied  { search } for  pid=176 comm="lmkd" name="1577" dev="proc" ino=12708 scontext=u:r:lmkd:s0 tcontext=u:r:release_app:s0 tclass=dir
<5>[  209.119937] type=1400 audit(9781760.879:28): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11657 scontext=u:r:lmkd:s0 tcontext=u:r:release_app:s0 tclass=file
<5>[  209.120105] type=1400 audit(9781760.879:29): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11657 scontext=u:r:lmkd:s0 tcontext=u:r:release_app:s0 tclass=file
<5>[  209.235597] type=1400 audit(9781760.999:30): avc:  denied  { search } for  pid=176 comm="lmkd" name="1600" dev="proc" ino=11659 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=dir
<5>[  209.235798] type=1400 audit(9781760.999:31): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11667 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=file
<5>[  209.236006] type=1400 audit(9781760.999:32): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11667 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=file
<5>[  214.297283] type=1400 audit(9781766.059:64): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11211 scontext=u:r:lmkd:s0 tcontext=u:r:untrusted_app:s0 tclass=file
<5>[  214.297415] type=1400 audit(9781766.059:65): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=11211 scontext=u:r:lmkd:s0 tcontext=u:r:untrusted_app:s0 tclass=file
<5>[  214.355060] type=1400 audit(9781766.119:66): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12907 scontext=u:r:lmkd:s0 tcontext=u:r:system_app:s0 tclass=file
<5>[  214.355236] type=1400 audit(9781766.119:67): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12907 scontext=u:r:lmkd:s0 tcontext=u:r:system_app:s0 tclass=file
<5>[  214.516920] type=1400 audit(9781766.279:68): avc:  denied  { search } for  pid=176 comm="lmkd" name="1907" dev="proc" ino=11742 scontext=u:r:lmkd:s0 tcontext=u:r:media_app:s0 tclass=dir
<5>[  214.678861] type=1400 audit(9781766.439:69): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12915 scontext=u:r:lmkd:s0 tcontext=u:r:media_app:s0 tclass=file
<5>[  214.678992] type=1400 audit(9781766.439:70): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12915 scontext=u:r:lmkd:s0 tcontext=u:r:media_app:s0 tclass=file
<5>[  214.708284] type=1400 audit(9781766.469:71): avc:  denied  { search } for  pid=176 comm="lmkd" name="1765" dev="proc" ino=12851 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=dir
<5>[  214.708435] type=1400 audit(9781766.469:72): avc:  denied  { write } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12870 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=file
<5>[  214.708648] type=1400 audit(9781766.469:73): avc:  denied  { open } for  pid=176 comm="lmkd" name="oom_score_adj" dev="proc" ino=12870 scontext=u:r:lmkd:s0 tcontext=u:r:shared_app:s0 tclass=file

Change-Id: Ie3c1ab8ce9e77742d0cc3c73f40010afd018ccd4

Otherwise we'll never see denials in userdebug or eng builds and
never make progress on confining it.  Of course we cannot truly
test until it is released into AOSP, but this prepares the way
and potentially allows for internal testing and collection of denials.

Change-Id: Ic9d1ba872d43f322e39ca6cffa0e725f1e223e7b
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>

lmkd low memory killer daemon

The kernel low memory killer logic has been moved to a new daemon
called lmkd.  ActivityManager communicates with this daemon over a
named socket.

This is just a placeholder policy, starting off in unconfined_domain.

Change-Id: Ia3f9a18432c2ae37d4f5526850e11432fd633e10