Restrict VM usage to platform_app.

Remove access from untrusted apps and instead grant it to platform_app
(but on user builds as well as debug).

Also restrict any app from creating a vsock_socket; using an already
created one is fine.

Bug: 193373841
Test: Microdroid demo app now gets a denial
Test: Rebuild demo with certifcate: platform, adb install, no denial
Change-Id: I7be011e05244767a42d4c56e26de792db4fe599d
This commit is contained in:
Alan Stokes 2021-09-07 12:25:38 +01:00 committed by Inseob Kim
parent c71b2c18cc
commit f96cd6557e
4 changed files with 8 additions and 9 deletions

View file

@ -117,9 +117,10 @@ neverallow all_untrusted_apps *:{
alg_socket nfc_socket kcm_socket qipcrtr_socket smc_socket xdp_socket
} *;
# Apps can read/write vsock created by virtualizationservice to communicate with the VM that they own,
# but nothing more than that (e.g. creating a new vsock, etc.)
neverallow all_untrusted_apps virtualizationservice:vsock_socket ~{ getattr read write };
# Apps can read/write an already open vsock (e.g. created by
# virtualizationservice) but nothing more than that (e.g. creating a
# new vsock, etc.)
neverallow all_untrusted_apps *:vsock_socket ~{ getattr read write };
# Disallow sending RTM_GETLINK messages on netlink sockets.
neverallow all_untrusted_apps domain:netlink_route_socket { bind nlmsg_readpriv };

View file

@ -108,6 +108,9 @@ dontaudit platform_app debugfs_tracing:file rw_file_perms;
# Allow platform apps to act as Perfetto producers.
perfetto_producer(platform_app)
# Allow platform apps to create VMs
virtualizationservice_use(platform_app)
###
### Neverallow rules
###

View file

@ -176,11 +176,6 @@ userdebug_or_eng(`
# the profiler (which would be profiling the app that is sending the signal).
allow untrusted_app_all simpleperf:process signal;
# Allow running a VM for test/demo purposes
userdebug_or_eng(`
virtualizationservice_use(untrusted_app_all)
')
with_native_coverage(`
# Allow writing coverage information to /data/misc/trace
allow domain method_trace_data_file:dir create_dir_perms;

View file

@ -43,7 +43,7 @@ type system_suspend_control_internal_service, service_manager_type;
type system_suspend_control_service, service_manager_type;
type update_engine_service, service_manager_type;
type update_engine_stable_service, service_manager_type;
type virtualization_service, app_api_service, service_manager_type;
type virtualization_service, service_manager_type;
type virtual_touchpad_service, service_manager_type;
type vold_service, service_manager_type;
type vr_hwc_service, service_manager_type;