/mnt/pass_through was introduced to allow the FUSE daemon unrestricted
access to the lower filesystem (or sdcardfs).
At zygote fork time, the FUSE daemon will have /mnt/pass_through/0
bind mounted to /storage instead of /mnt/user/0. To keep /sdcard
(symlink to /storage/self/primary) paths working, we create a
'self' directory with an additional 'primary' symlink to
/mnt/pass_through/0/emulated/0 which is a FUSE mount point.
The following components need varying sepolicy privileges:
Vold: Creates the self/primary symlink and mounts the lower filesystem
on /mnt/pass_through/0/emulated. So needs create_dir and mount access
+ create_file access for the symlink
zygote: In case zygote starts an app before vold sets up the paths.
This is unlikely but can happen if the FUSE daemon (a zygote forked app)
is started before system_server completes vold mounts.
Same sepolicy requirements as vold
installd: Needs to clear/destroy app data using lower filesystem
mounted on /mnt/pass_through so needs read_dir access to walk
/mnt/pass_through
priv_app (FUSE daemon): Needs to server content from the lower
filesystem mounted on /mnt/pass_through so needs read_dir access to
walk /mnt/pass_through
Bug: 135341433
Test: adb shell ls /mnt/pass_through/0/self/primary
Change-Id: I16e35b9007c2143282600c56adbc9468a1b7f240
For performance reasons, we want to bind-mount parts of the lower
filesystem on top of /data/media.
Bug: 137890172
Test: No denials when mounting
Change-Id: Ide8fc07cdeb6a6816585af1582bee69bc68043af
The property is set to inform kernel to do a warm_reset on the next
reboot. This is useful to persist the logs to debug device boot
failures. More details in http://go/rvc-ota-persist-logs.
The property is set to 1 by update_engine after an OTA. And it's set to
0 by update_verifier or vold after we mark the current slot boot
successful.
The property is read by vendor_init. And according to its value,
vendor_init writes a particular sysfs file to schedule a warm reset
on the following reboot.
Without the new context, the denial message says:
[ 13.423163] audit: type=1107 audit(1746393.166:8): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=u:r:init:s0 msg='avc: denied { read } for property=ota.warm_reset pid=0 uid=0 gid=0 scontext=u:r:vendor_init:s0 tcontext=u:object_r:default_prop:s0 tclass=file permissive=0'
[ 23.096497] init: Unable to set property 'OTA.warm_reset' from uid:0 gid:2001 pid:841: SELinux permission check failed
[ 23.096574] type=1107 audit(1573768000.668:42): uid=0 auid=4294967295 ses=4294967295 subj=u:r:init:s0 msg='avc: denied { set } for property=OTA.warm_reset pid=841 uid=0 gid=2001 scontext=u:r:update_verifier:s0 tcontext=u:object_r:default_prop:s0 tclass=property_service permissive=0'
[ 23.108430] update_verifier: Failed to reset the warm reset flag
Bug: 143489994
Test: check the property can be set by update_engine, and read by vendor_init
Change-Id: I87c12a53a138b72ecfed3ab6a4d846c20f5a8484
Also add neverallow rules to enforce that unintended domains aren't
allowed to use any of the fscrypt ioctls.
(Originally based on a patch by Satya Tangirala <satyat@google.com>)
Bug: 140500828
Test: see I296ef78138578a3fd773797ac0cd46af1296b959
Change-Id: I01e81edf0d948af254ddf4275702e7224b2698e4
Give /data itself a different label to its contents, to ensure that
only init creates files and directories there.
This change originally landed as aosp/1106014 and was reverted in
aosp/1116238 to fix b/140402208. aosp/1116298 fixes the underlying
problem, and with that we can re-land this change.
Bug: 139190159
Bug: 140402208
Test: aosp boots, logs look good
Change-Id: I1a366c577a0fff307ca366a6844231bcf8afe3bf
Give /data itself a different label to its contents, to ensure that
only init creates files and directories there.
Bug: 139190159
Test: aosp boots, logs look good
Change-Id: I3ee654a928bdab3f5d435ab6ac24040d9bdd9abe
vold needs write permissions for /sys/block/*/uevent to perform a
coldboot.
https://android.googlesource.com/platform/system/vold/+/refs/heads/master/main.cpp#139
This denial is seen on cuttlefish:
avc: denied { write } for name=uevent dev=sysfs ino=11649
scontext=u:r:vold:s0 tcontext=u:object_r:sysfs_devices_block:s0
tclass=file permissive=1
Pixel devices resolve this denial in device policy, but since coldboot
is performed from platform code, the corresponding permission should be
in /system/sepolicy
Bug: 28053261
Test: boot cuttlefish without above denial
Change-Id: I2de08db603e2d287e8021af70ee8e69266d7736f
System suspend service is not a HAL, so avoid using HAL-specific macros
and attributes.
Use system_suspend_server attribute for ISystemSuspend.hal permissions.
Use system_suspend type directly for internal .aidl interface
permissions.
Bug: 126259100
Test: m selinux_policy
Test: blueline boots; wakelocks can still be acquired; device suspends
if left alone.
Change-Id: Ie811e7da46023705c93ff4d76d15709a56706714
This lets update_verifier call supportsCheckpoint to defer marking the
boot as successful when we may end up failing before we would commit
the checkpoint. In this case, we will mark the boot as successful just
before committing the checkpoint.
Test: Check that marking the boot as succesful was deferred in
update_verifier, and done later on.
Change-Id: I9b4f3dd607ff5301860e78f4604b600b4ee416b7
all_untrusted_apps apart from untrusted_app_{25, 27} and mediaprovider
are now expected to go to ashmemd for /dev/ashmem fds.
Give coredomain access to ashmemd, because ashmemd is the default way
for coredomain to get a /dev/ashmem fd.
Bug: 113362644
Test: device boots, ashmemd running
Test: Chrome app works
Test: "lsof /system/lib64/libashmemd_client.so" shows
libashmemd_client.so being loaded into apps.
Change-Id: I279448c3104c5d08a1fefe31730488924ce1b37a
To configure read-ahead on loop devices, eg.
/sys/devices/virtual/block/loop0/queue/read_ahead_kb
Bug: 120776455
Test: configuring read-ahead on loop devices works from apexd
Change-Id: Ib25372358e8ca62fa634daf286e4b64e635fac58
Never use popen, just execvp directly
Test: Two tests
- Ensure Marlin device boots and vold_prepare_subdirs is called
successfully
- Try adb shell sm set-virtual-disk true, see that eg sgdisk output is
logged.
Bug: 26735063
Bug: 113796163
Change-Id: Icb34140429db85098a0118a2b833772e3620e7ac
Hals have 3 attributes associated with them, the attribute itself, the
_client attribute, and the _server attribute. Only the server attribute
isn't expanded using the expandattribute keyword, and as a result, is
the only attribute which can be used in neverallow rules.
Fix neverallow rule to use hal_bootctl_server, which is not expanded,
instead of hal_bootctl.
Introduced in: https://android-review.googlesource.com/c/platform/system/sepolicy/+/777178
Test: policy compiles
Bug: 119500144
Change-Id: I8cff9cc03f4c30704175afb203c68f237fbd61ca
The auditallow added in commit
7a4af30b38 ("Start the process of locking
down proc/net", May 04 2018), has not been triggered. This is safe to
delete.
Test: Policy compiles
Test: no collected SELinux denials
Bug: 68016944
Change-Id: Ib45519b91742d09e7b93bbaf972e558848691a80
BLKDISCARD is used by vold while wiping block devices
b2455747a9/Utils.cpp (619)
BLKGETSIZE is used to determine the size of the block device. Ideally
code should not be using this ioctl, as it fails for devices >= 2T in
size. Vold indirectly uses this when executing /system/bin/newfs_msdos.
Arguably this is a bug in newfs_msdos, as BLKGETSIZE64 should be used
instead.
Code: 0c7e133c7f/mkfs_msdos.c (845)
Addresses the following denials:
audit(0.0:24): avc: denied { ioctl } for comm="Binder:588_2" path="/dev/block/vold/public:7,9" dev="tmpfs" ino=106407 ioctlcmd=1277 scontext=u:r:vold:s0 tcontext=u:object_r:vold_device:s0 tclass=blk_file permissive=0
audit(0.0:25): avc: denied { ioctl } for comm="newfs_msdos" path="/dev/block/vold/public:7,9" dev="tmpfs" ino=106407 ioctlcmd=1260 scontext=u:r:vold:s0 tcontext=u:object_r:vold_device:s0 tclass=blk_file permissive=0
Test: policy compiles.
Bug: 119562530
Change-Id: Ib7198daf150d6f2578545a6a402e0313069ea2b4
We are moving AppFuse mount from system_server's mount namespace to
vold. Hence, we could reduce the SELinux permissions given to
system_server, in the expense of adding allow rules to vold and
letting appdomain have access to vold's fd.
Bug: 110379912
Test: testOpenProxyFileDescriptor passes (after vold and
system_server code changes)
Change-Id: I827a108bd118090542354360a8c90b295e6a0fef
Update the "allowxperm" to reflect the various ioctl() performed in
the vold source code.
Bug: 118437832
Test: atest android.os.storage.cts.StorageManagerTest
Change-Id: Ide3a09104d8b4ce7fa2b7e23e9b215139186f595
We are moving AppFuse mount from system_server's mount namespace to
vold. Hence, we could reduce the SELinux permissions given to
system_server, in the expense of adding allow rules to vold and
letting appdomain have access to vold's fd.
Bug: 110379912
Test: testOpenProxyFileDescriptor passes (after vold and
system_server code changes)
Change-Id: I4731a8ec846c5cb84ec4b680d51938494e8ddd75
Start enforcing the use of ioctl restrictions on all Android block
devices. Domains which perform ioctls on block devices must be explicit
about what ioctls they issue. The only ioctls allowed by default are
BLKGETSIZE64, BLKSSZGET, FIOCLEX, and FIONCLEX.
Test: device boots and no problems.
Change-Id: I1195756b20cf2b50bede1eb04a48145a97a35867
This is needed to find the file on the raw block device, so it can be
securely deleted.
Addresses the following denials:
type=1400 audit(0.0:492): avc: denied { ioctl } for comm="secdiscard" path="/data/misc/vold/user_keys/ce/10/current/encrypted_key" dev="dm-3" ino=9984 ioctlcmd=0x660b scontext=u:r:vold:s0 tcontext=u:object_r:vold_data_file:s0 tclass=file permissive=0
type=1400 audit(0.0:517): avc: denied { ioctl } for comm="secdiscard" path="/data/misc/vold/user_keys/ce/11/current/secdiscardable" dev="dm-3" ino=9581 ioctlcmd=0x660b scontext=u:r:vold:s0 tcontext=u:object_r:vold_data_file:s0 tclass=file permissive=0
type=1400 audit(0.0:694): avc: denied { ioctl } for comm="secdiscard" path="/data/misc/vold/user_keys/ce/0/current/keymaster_key_blob" dev="dm-3" ino=9903 ioctlcmd=0x660b scontext=u:r:vold:s0 tcontext=u:object_r:vold_data_file:s0 tclass=file permissive=0
Test: policy compiles and device boots
Change-Id: I1adf21b7fa92b1f92ce76532f4d9337a4d58a2e5
Remove kernel attack surface associated with ioctls on plain files. In
particular, we want to ensure that the ioctls FS_IOC_ENABLE_VERITY and
FS_IOC_MEASURE_VERITY are not exposed outside a whitelisted set of
entities. However, it's straight forward enough to turn on ioctl
whitelisting for everything, so we choose to do so.
Test: policy compiles and device boots
Test: device boots with data wipe
Test: device boots without data wipe
Change-Id: I545ae76dddaa2193890eeb1d404db79d1ffa13c2
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
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
...to reflect that the HAL operates on storage devices,
not filesystem.
Bug: 111655771
Test: compiles
Change-Id: Ibb0572cb1878359e5944aa6711331f0c7993ba6e
Merged-In: Ibb0572cb1878359e5944aa6711331f0c7993ba6e
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
