The steps involved in setting up profiling and stack unwinding are
described in detail at go/perfetto-perf-android.
To summarize the interesting case: the daemon uses cpu-wide
perf_event_open, with userspace stack and register sampling on. For each
sample, it identifies whether the process is profileable, and obtains
the FDs for /proc/[pid]/{maps,mem} using a dedicated RT signal (with the
bionic signal handler handing over the FDs over a dedicated socket). It
then uses libunwindstack to unwind & symbolize the stacks, sending the
results to the central tracing daemon (traced).
This patch covers the app profiling use-cases. Splitting out the
"profile most things on debug builds" into a separate patch for easier
review.
Most of the exceptions in domain.te & coredomain.te come from the
"vendor_file_type" allow-rule. We want a subset of that (effectively all
libraries/executables), but I believe that in practice it's hard to use
just the specific subtypes, and we're better off allowing access to all
vendor_file_type files.
Bug: 137092007
Change-Id: I4aa482cfb3f9fb2fabf02e1dff92e2b5ce121a47
This will let an app delegate network operations to an
isolatedProcess=true service. Chromium will use this to separate out
network protocol parsing of untrusted Internet data from the main app
process into a sandboxed service process.
Bug: 147444459
Test: Build and boot sargo. Chromium runs.
Change-Id: Ia7f54d481676a03b96f512015e6adcf920a014c3
Only allow apps targetting < Q and ephemeral apps to open /dev/ashmem.
Ephemeral apps are not distinguishable based on target API. So allow
ephemeral_app to open /dev/ashmem for compatibility reasons.
For sake of simplicity, allow all domains /dev/ashmem permissions other
than "open". Reason being that once we can remove "open" access
everywhere, we can remove the device altogether along with other
permission.
Bug: 134434505
Test: boot crosshatch; browse internet, take picture;
no ashmem_device denials
Change-Id: Ie2464c23d799550722580a21b4f6f344983b43ba
This is needed to get Java heap graphs.
Test: flash aosp; profile system_server with setenforce 1
Bug: 136210868
Change-Id: I87dffdf28d09e6ce5f706782422510c615521ab3
Only allow apps targetting < Q and ephemeral apps to open /dev/ashmem.
Ephemeral apps are not distinguishable based on target API. So allow
ephemeral_app to open /dev/ashmem for compatibility reasons.
For sake of simplicity, allow all domains /dev/ashmem permissions other
than "open". Reason being that once we can remove "open" access
everywhere, we can remove the device altogether along with other
permission.
Bug: 134434505
Test: boot crosshatch; browse internet, take picture;
no ashmem_device denials
Change-Id: Ib4dddc47fcafb2697795538cdf055f305fa77799
If kernel is built with CONFIG_TRANSPARENT_HUGEPAGE optimization,
libjemalloc5 will attempt to read
/sys/kernel/mm/transparent_hugepage/enabled and hit an SELinux denial.
Various denials similiar to the following are seen on cuttlefish:
avc: denied { open } for comm="surfaceflinger"
path="/sys/kernel/mm/transparent_hugepage/enabled" dev="sysfs" ino=776
scontext=u:r:surfaceflinger:s0 tcontext=u:object_r:sysfs:s0 tclass=file
permissive=1
Bug: 28053261
Test: boot cuttlefish without above denials.
Change-Id: Ic33f12d31aacc42d662a8c5c297fbb5f84d4deea
We are only interested in removing "open" access from apps, so leave
apps with (rw_file_perms - open) permissions to /dev/ashmem
Bug: 126627315
Test: emulator boots without denials to /dev/ashmem
Change-Id: I7f03fad5e4e82aebd1b6272e4956b16f86043637
Apps are no longer allowed open access to /dev/ashmem, unless they
target API level < Q.
Bug: 113362644
Test: device boots, Chrome, instant apps work
Change-Id: I1cff08f26159fbf48a42afa7cfa08eafa1936f42
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
This patch extends the current debug-specific rules to cover user
builds. As a reminder, on user, the target process fork-execs a private
heapprofd process, which then performs stack unwinding & talking to the
central tracing daemon while staying in the target's domain. The central
heapprofd daemon is only responsible for identifying targets & sending
the activation signal. On the other hand, on debug, the central
heapprofd can handle all processes directly, so the necessary SELinux
capabilities depend on the build type.
These rules are necessary but not sufficient for profiling. For zygote
children, the libc triggering logic will also check for the app to
either be debuggable, or go/profileable.
For more context, see go/heapprofd-security & go/heapprofd-design.
Note that I've had to split this into two separate macros, as
exec_no_trans - which is necessary on user, but nice-to-have on debug -
conflicts with a lot of neverallows (e.g. HALs and system_server) for
the wider whitelisting that we do on debug builds.
Test: built & flashed on {blueline-userdebug, blueline-user}, activated profiling of whitelisted/not domains & checked for lack of denials in logcat.
Bug: 120409382
Change-Id: Id0defc3105b99f777bcee2046d9894a2b39c6a29
The application zygote is a new sort of zygote process that is a
child of the regular zygote. Each application zygote is tied to the
application for which it's launched. Once it's started, it will
pre-load some of the code for that specific application, much like
the regular zygote does for framework code.
Once the application zygote is up and running, it can spawn
isolated service processes that run in the isolated_app domain. These
services can then benefit from already having the relevant
application code and data pre-loaded.
The policy is largely the same as the webview_zygote domain,
however there are a few crucial points where the policy is different.
1) The app_zygote runs under the UID of the application that spawned
it.
2) During app_zygote launch, it will call a callback that is
controlled by the application, that allows the application to
pre-load code and data that it thinks is relevant.
Especially point 2 is imporant: it means that untrusted code can run
in the app_zygote context. This context is severely limited, and the
main concern is around the setgid/setuid capabilities. Those conerns
are mitigated by installing a seccomp filter that only allows
setgid/setuid to be called in a safe range.
Bug: 111434506
Test: app_zygote can start and fork children without denials.
Change-Id: I1cc49ee0042d41e5ac6eb81d8f8a10ba448d4832
1b1d133be5 added the process2 class but
forgot to suppress SELinux denials associated with these permissions
for the su domain. Suppress them.
Ensure xdp_socket is in socket_class_set, so the existing dontaudit rule
in su.te is relevant. Inspired by
66a337eec6
Add xdp_socket to various other neverallow rules.
Test: policy compiles.
Change-Id: If5422ecfa0cc864a51dd69559a51d759e078c8e7
Require all SELinux domains which have permission to perform ioctls on
/dev/tun explicitly specify what ioctls they perform. Only allow the
safe defaults FIOCLEX and FIONCLEX, which are alternate, uncommon ways
to set and unset the O_CLOEXEC flag.
Remove app's ability to issue *any* ioctls on /dev/tun, period. Add
neverallow assertions (compile time assertion + CTS test) to prevent
regressions.
Limit system_server's ability to perform ioctls on /dev/tun to FIOCLEX,
FIONCLEX, TUNGETIFF, and TUNSETIFF. Testing and source code examination
shows that only TUNGETIFF and TUNSETIFF are used by system_server.
The goal of this change is to put SELinux ioctl controls in place for
/dev/tun, so we don't have to maintain the custom kernel patch at
11cee2be0c%5E%21
Delete the neverallow assertion in isolated_app.te. This is already
covered by the assertion present in app_neverallows.te.
Test: cts-tradefed run cts -m CtsHostsideNetworkTests -t com.android.cts.net.HostsideVpnTests
Test: cts-tradefed run cts -m CtsHostsideNetworkTests
Test: cts-tradefed run cts -m CtsNetTestCases
Bug: 111560739
Bug: 111560570
Change-Id: Ibe1c3a9e880db0bee438535554abdbc6d84eec45
Kernel commit 3ba4bf5f1e2c ("selinux: add a map permission check for mmap")
added a map permission check on mmap so that we can
distinguish memory mapped access (since it has different implications
for revocation). system/sepolicy commit
4397f08288 introduced the permission to
Android and updated common macros. Since then, we've been adding more
mmap support where it was accidentally omitted.
Add the ability for isolated_apps to mmap() app data files. There's no
reason why this should be blocked. Also fixup sdcard access which has
similar problems.
Bug: 118760652
Bug: https://crbug.com/892014
Test: policy compiles.
Change-Id: I3823f313103c9dcedf3b21d081a22f8fbb271c02
Remove blanket coredomain access to same_process_hal_file in favor of
granular access. This change takes into account audits from go/sedenials
(our internal dogfood program)
Bug: 37211678
Test: m selinux_policy
Change-Id: I5634fb65c72d13007e40c131a600585a05b8c4b5
same_process_hal_file is exempted from many Treble neverallows. We want
to know which processes access this type to eventually constrain access
to it.
Bug: 37211678
Test: m selinux_policy
Change-Id: I61c0df21250eb1b1ae2d9c5fa9c801a828539813
Isolated apps provide a very strict security guarantee, including the
inability to create networking sockets like TCP / UDP sockets. Add an
SELinux neverallow assertion to test for this and prevent regressions.
Test: policy compiles.
Change-Id: I2618abb17375707eb1048e89faa46f57d33e1df4
Currently, both untrusted apps and priv-apps use the SELinux file label
"app_data_file" for files in their /data/data directory. This is
problematic, as we really want different rules for such files. For
example, we may want to allow untrusted apps to load executable code
from priv-app directories, but disallow untrusted apps from loading
executable code from their own home directories.
This change adds a new file type "privapp_data_file". For compatibility,
we adjust the policy to support access privapp_data_files almost
everywhere we were previously granting access to app_data_files
(adbd and run-as being exceptions). Additional future tightening is
possible here by removing some of these newly added rules.
This label will start getting used in a followup change to
system/sepolicy/private/seapp_contexts, similar to:
-user=_app isPrivApp=true domain=priv_app type=app_data_file levelFrom=user
+user=_app isPrivApp=true domain=priv_app type=privapp_data_file levelFrom=user
For now, this newly introduced label has no usage, so this change
is essentially a no-op.
Test: Factory reset and boot - no problems on fresh install.
Test: Upgrade to new version and test. No compatibility problems on
filesystem upgrade.
Change-Id: I9618b7d91d1c2bcb5837cdabc949f0cf741a2837
The webview_zygote is now launched as a child-zygote process from the
main zygote process.
Bug: 63749735
Test: m
Test: Launch "Third-party licenses" activity from Settings, and it
renders correctly via the WebView.
Merged-In: I9c948b58a969d35d5a5add4b6ab62b8f990645d1
Change-Id: I153476642cf14883b0dfea0d9f5b3b5e30ac1c08
Perfetto is a performance instrumentation and logging framework,
living in AOSP's /external/pefetto.
Perfetto introduces in the system one binary and two daemons
(the binary can specialize in either depending on the cmdline).
1) traced: unprivileged daemon. This is architecturally similar to logd.
It exposes two UNIX sockets:
- /dev/socket/traced_producer : world-accessible, allows to stream
tracing data. A tmpfs file descriptor is sent via SCM_RIGHTS
from traced to each client process, which needs to be able to
mmap it R/W (but not X)
- /dev/socket/traced_consumer : privilege-accessible (only from:
shell, statsd). It allows to configure tracing and read the trace
buffer.
2) traced_probes: privileged daemon. This needs to:
- access tracingfs (/d/tracing) to turn tracing on and off.
- exec atrace
- connect to traced_producer to stream data to traced.
init.rc file:
https://android-review.googlesource.com/c/platform/external/perfetto/+/575382/14/perfetto.rc
Bug: 70942310
Change-Id: Ia3b5fdacbd5a8e6e23b82f1d6fabfa07e4abc405
isolated_apps are intended to be strictly limited in the /sys files
which can be read. Add a neverallow assertion to guarantee this on all
Android compatible devices.
Test: policy compiles.
Change-Id: I2980291dcf4e74bb12c81199d61c5eb8a182036c
Bullhead and dragon are broken. Revert until I can fix
those builds.
Dragon:
libsepol.report_failure: neverallow on line 113 of system/sepolicy/private/isolated_app.te (or line 26264 of policy.conf) violated by allow isolated_app sysfs_socinfo:file { ioctl read lock open };
Bullhead:
libsepol.report_failure: neverallow on line 113 of system/sepolicy/private/isolated_app.te (or line 26283 of policy.conf) violated by allow isolated_app sysfs_power_management:file { ioctl read lock open };
libsepol.report_failure: neverallow on line 113 of system/sepolicy/private/isolated_app.te (or line 26283 of policy.conf) violated by allow isolated_app sysfs_socinfo:file { ioctl read lock open };
libsepol.report_failure: neverallow on line 113 of system/sepolicy/private/isolated_app.te (or line 26283 of policy.conf) violated by allow isolated_app sysfs_thermal:file { ioctl read lock open };
libsepol.check_assertions: 3 neverallow failures occurred
This reverts commit 579366a0ba.
Change-Id: I1ea4824e226c06628769898299f2e322060d0d06
Test: policy compiles.
isolated_apps are intended to be strictly limited in the /sys files
which can be read. Add a neverallow assertion to guarantee this on all
Android compatible devices.
Test: policy compiles.
Change-Id: I47aceefa3f43a7ea9e526f6f0ef377d0b4efbe3a
On PRODUCT_FULL_TREBLE devices, non-vendor domains (except vendor
apps) are not permitted to use Binder. This commit thus:
* groups non-vendor domains using the new "coredomain" attribute,
* adds neverallow rules restricting Binder use to coredomain and
appdomain only, and
* temporarily exempts the domains which are currently violating this
rule from this restriction. These domains are grouped using the new
"binder_in_vendor_violators" attribute. The attribute is needed
because the types corresponding to violators are not exposed to the
public policy where the neverallow rules are.
Test: mmm system/sepolicy
Test: Device boots, no new denials
Test: In Chrome, navigate to ip6.me, play a YouTube video
Test: YouTube: play a video
Test: Netflix: play a movie
Test: Google Camera: take a photo, take an HDR+ photo, record video with
sound, record slow motion video with sound. Confirm videos play
back fine and with sound.
Bug: 35870313
Change-Id: I0cd1a80b60bcbde358ce0f7a47b90f4435a45c95
The neverallows in untrusted_app will all apply equally to ephemeral app
and any other untrusted app domains we may add, so this moves them to a
dedicated separate file.
This also removes the duplicate rules from isolated_app.te and ensures
that all the untrusted_app neverallows also apply to isolated_app.
Test: builds
Change-Id: Ib38e136216ccbe5c94daab732b7ee6acfad25d0b
This leaves only the existence of isolated_app domain as public API.
All other rules are implementation details of this domain's policy and
are thus now private.
Test: No change to policy according to sesearch, except for
disappearance of all allow rules from isolated_app_current
attribute (as expected).
Bug: 31364497
Change-Id: I499a648e515628932b7bcd188ecbfbe4a247f2f3
app_domain was split up in commit: 2e00e6373f to
enable compilation by hiding type_transition rules from public policy. These
rules need to be hidden from public policy because they describe how objects are
labeled, of which non-platform should be unaware. Instead of cutting apart the
app_domain macro, which non-platform policy may rely on for implementing new app
types, move all app_domain calls to private policy.
(cherry-pick of commit: 76035ea019)
Bug: 33428593
Test: bullhead and sailfish both boot. sediff shows no policy change.
Change-Id: I4beead8ccc9b6e13c6348da98bb575756f539665
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
