Commit graph

9 commits

Author SHA1 Message Date
Jeff Vander Stoep
ab82125fc8 Improve tests protecting private app data
In particular, add assertions limiting which processes may
directly open files owned by apps. Reduce this to just apps, init,
and installd. App data is protected by a combination of selinux
permissions and Unix permissions, so limiting the open permission to
just apps (which are not allowed to have CAP_DAC_OVERRIDE or
CAP_DAC_READ_SEARCH) ensures that only installd and init have
complete access an app's private directory.

In addition to apps/init/installd, other processes currently granted
open are mediaserver, uncrypt, and vold. Uncrypt's access appears to
be deprecated (b/80299612). Uncrypt now uses /data/ota_package
instead. b/80418809 and b/80300620 track removal for vold and
mediaserver.

Test: build/boot aosp_taimen-userdebug. Verify no "granted" audit
messages in the logs.
Bug: 80190017
Bug: 80300620
Bug: 80418809
Fixes: 80299612
Change-Id: I153bc7b62294b36ccd596254a5976dd887fed046
2018-05-29 13:47:49 -07:00
Benjamin Gordon
9b2e0cbeea sepolicy: Add rules for non-init namespaces
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
2017-11-21 08:34:32 -07:00
Tri Vo
04fb82f232 /proc, /sys access from uncrypt, update_engine, postinstall_dexopt
New types:
1. proc_random
2. sysfs_dt_firmware_android

Labeled:
1. /proc/sys/kernel/random as proc_random.
2. /sys/firmware/devicetree/base/firmware/android/{compatible, fstab,
vbmeta} as sysfs_dt_firmware_android.

Changed access:
1. uncrypt, update_engine, postinstall_dexopt have access to generic proc
and sysfs labels removed.
2. appropriate permissions were added to uncrypt, update_engine,
update_engine_common, postinstall_dexopt.

Bug: 67416435
Bug: 67416336
Test: fake ota go/manual-ab-ota runs without denials
Test: adb sideload runs without denials to new types
Change-Id: Id31310ceb151a18652fcbb58037a0b90c1f6505a
2017-10-24 16:40:45 +00:00
Tri Vo
9fa8ad6eb8 Give uncrypt access to /proc/cmdline.
Removes uncrypt access to the rest of /proc.
Fixes this denial, which can be triggered from recovery_component_test:
[  142.540819] type=1400 audit(1506983074.139:23): avc: denied { read }
for pid=5767 comm=uncrypt name=cmdline dev=proc ino=4026532114
scontext=u:r:uncrypt:s0 tcontext=u:object_r:proc_cmdline:s0 tclass=file
permissive=0

Bug: 66497047
Test: recovery_component_test --gtest_filter=UncryptTest.*
no more denials to /proc/cmdline
Change-Id: If1a7630779d667d52a0cc44114ef6177982de21c
2017-10-02 15:31:48 -07:00
Jeff Vander Stoep
275f6dd5a3 domain_deprecated: remove sysfs rules
Clean up the remaining granted permissions in domain_deprecated.

avc: granted { read open } for comm="uncrypt"
path="/sys/firmware/devicetree/base/firmware/android/fstab/compatible"
dev="sysfs" ino=17591 scontext=u:r:uncrypt:s0
tcontext=u:object_r:sysfs:s0 tclass=file
avc: granted { getattr } for comm="uncrypt"
path="/sys/firmware/devicetree/base/firmware/android/compatible"
dev="sysfs" ino=17583 scontext=u:r:uncrypt:s0
tcontext=u:object_r:sysfs:s0 tclass=file

vc: granted { read open } for comm="update_engine"
path="/sys/firmware/devicetree/base/firmware/android/fstab" dev="sysfs"
ino=17258 scontext=u:r:update_engine:s0 tcontext=u:object_r:sysfs:s0
tclass=dir
avc: granted { getattr } for comm="update_engine"
path="/sys/firmware/devicetree/base/firmware/android/fstab/compatible"
dev="sysfs" ino=17259 scontext=u:r:update_engine:s0
tcontext=u:object_r:sysfs:s0 tclass=file

Bug: 28760354
Test: build
Change-Id: Id318ce84894c1001361923f5205de093a15c1e6a
2017-07-27 20:03:16 +00:00
Jeff Vander Stoep
c15d54ef1a domain_deprecated: remove proc access
Remove "granted" logspam. Grante the observed permissions to the
individual processes that need them and remove the permission from
domain_deprecated.

avc: granted { read open } for comm="ndroid.settings"
path="/proc/version" dev="proc" ino=4026532081
scontext=u:r:system_app:s0 tcontext=u:object_r:proc:s0 tclass=file
avc: granted { getattr } for comm=4173796E635461736B202332
path="/proc/pagetypeinfo" dev="proc" ino=4026532129
scontext=u:r:system_app:s0 tcontext=u:object_r:proc:s0 tclass=file

avc: granted { read open } for comm="uncrypt" path="/proc/cmdline"
dev="proc" ino=4026532072 scontext=u:r:uncrypt:s0
tcontext=u:object_r:proc:s0 tclass=file

avc: granted { read open } for comm="update_engine"
path="/proc/sys/kernel/random/boot_id" dev="proc" ino=15852829
scontext=u:r:update_engine:s0 tcontext=u:object_r:proc:s0 tclass=file

avc: granted { read open } for comm="tiveportallogin"
path="/proc/vmstat" dev="proc" ino=4026532130
scontext=u:r:platform_app:s0:c512,c768 tcontext=u:object_r:proc:s0
tclass=file

This change is specifically not granting the following since it
should not be allowed:
avc: granted { read open } for comm="crash_dump64"
path="/proc/filesystems" dev="proc" ino=4026532416
scontext=u:r:dex2oat:s0 tcontext=u:object_r:proc:s0 tclass=file
avc: granted { read } for comm="crash_dump64" name="filesystems"
dev="proc" ino=4026532416 scontext=u:r:dex2oat:s0
tcontext=u:object_r:proc:s0 tclass=file
avc: granted { getattr } for comm="crash_dump64"
path="/proc/filesystems" dev="proc" ino=4026532416
scontext=u:r:dex2oat:s0 tcontext=u:object_r:proc:s0 tclass=file

Bug: 64032843
Bug: 28760354
Test: build
Change-Id: Ib309e97b6229bdf013468dca34f606c0e8da96d0
2017-07-25 17:34:27 -07:00
Jeff Vander Stoep
7c34e83fcd Move domain_deprecated into private policy
This attribute is being actively removed from policy. Since
attributes are not being versioned, partners must not be able to
access and use this attribute. Move it from private and verify in
the logs that rild and tee are not using these permissions.

Bug: 38316109
Test: build and boot Marlin
Test: Verify that rild and tee are not being granted any of these
      permissions.
Merged-In: I31beeb5bdf3885195310b086c1af3432dc6a349b
Change-Id: I31beeb5bdf3885195310b086c1af3432dc6a349b
(cherry picked from commit 76aab82cb3)
2017-07-24 07:39:54 -07:00
Jeff Vander Stoep
790f4c7e20 domain_deprecated: remove cache access
Address the "granted" permissions observed in the logs including:

tcontext=uncrypt
avc: granted { search } for comm="uncrypt" name="/" dev="mmcblk0p40"
ino=2 scontext=u:r:uncrypt:s0 tcontext=u:object_r:cache_file:s0
tclass=dir

tcontext=install_recovery
avc: granted { search } for comm="applypatch" name="saved.file"
scontext=u:r:install_recovery:s0 tcontext=u:object_r:cache_file:s0
tclass=dir
avc: granted { read } for comm="applypatch" name="saved.file"
dev="mmcblk0p6" ino=14 scontext=u:r:install_recovery:s0
tcontext=u:object_r:cache_file:s0 tclass=file
avc: granted { getattr } for comm="applypatch" path="/cache/saved.file"
dev="mmcblk0p6" ino=14 scontext=u:r:install_recovery:s0
tcontext=u:object_r:cache_file:s0 tclass=file

tcontext=update_engine
avc: granted { search } for comm="update_engine" name="cache"
dev="sda35" ino=1409025 scontext=u:r:update_engine:s0
tcontext=u:object_r:cache_file:s0 tclass=dir"
avc: granted { read } for comm="update_engine" name="update.zip"
dev="sda35" ino=1409037 scontext=u:r:update_engine:s0
tcontext=u:object_r:cache_file:s0:c512,c768 tclass=file
avc: granted { read } for comm="update_engine" name="cache" dev="dm-0"
ino=16 scontext=u:r:update_engine:s0 tcontext=u:object_r:cache_file:s0
tclass=lnk_file

Bug: 28760354
Test: build policy.
Merged-In: Ia13fe47268df904bd4f815c429a0acac961aed1e
Change-Id: Ia13fe47268df904bd4f815c429a0acac961aed1e
2017-07-10 22:06:33 +00:00
dcashman
cc39f63773 Split general policy into public and private components.
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
2016-10-06 13:09:06 -07:00
Renamed from uncrypt.te (Browse further)