sepolicy for ashmemd

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
diff --git a/private/app_neverallows.te b/private/app_neverallows.te
index 4ecb355..e46c4ef 100644
--- a/private/app_neverallows.te
+++ b/private/app_neverallows.te
@@ -334,3 +334,13 @@
 
 # Untrusted apps are not allowed to use cgroups.
 neverallow all_untrusted_apps cgroup:file *;
+
+# TODO(b/113362644): remove open permission from these domains.
+# Untrusted apps targetting >= Q are not allowed to open /dev/ashmem directly.
+#neverallow {
+#  all_untrusted_apps
+# TODO(b/113362644): route mediaprovider to ashmemd
+#  -mediaprovider
+#  -untrusted_app_25
+#  -untrusted_app_27
+#} ashmem_device:chr_file open;