Allow init to read /sys/block/dm-XX/dm/name
In order to remount ext4 userdata into checkpointing mode, init will
need to delete all devices from dm-stack it is mounted onto (e.g.
dm-bow, dm-crypto). For that it needs to get name of a dm-device by
reading /sys/block/dm-XX/dm/name file.
Test: adb shell setprop sys.init.userdata_remount.force_umount_f2fs 1
Test: adb shell /system/bin/vdc checkpoint startCheckpoint 1
Test: adb reboot userspace
Test: adb shell dumpsys activity
Bug: 135984674
Bug: 143970043
Change-Id: I919a4afdce8a4f88322f636fdf796a2f1a955d04
diff --git a/private/init.te b/private/init.te
index 3edd021..463f098 100644
--- a/private/init.te
+++ b/private/init.te
@@ -30,6 +30,12 @@
allow init su:process { siginh rlimitinh };
')
+# Allow init to figure out name of dm-device from it's /dev/block/dm-XX path.
+# This is useful in case of remounting ext4 userdata into checkpointing mode,
+# since it potentially requires tearing down dm-devices (e.g. dm-bow, dm-crypto)
+# that userdata is mounted onto.
+allow init sysfs_dm:file read;
+
# Allow the BoringSSL self test to request a reboot upon failure
set_prop(init, powerctl_prop)