Merge "trusty: rpmb_dev: Prevent desync between rpmb_dev and storageproxyd" am: 30b0838b70

Original change: https://android-review.googlesource.com/c/platform/system/core/+/1360681

Change-Id: I85b0dfc9092d44023d5c5d5dc5bbc1a867f765e4
diff --git a/trusty/utils/rpmb_dev/rpmb_dev.c b/trusty/utils/rpmb_dev/rpmb_dev.c
index af97eba..5de1efa 100644
--- a/trusty/utils/rpmb_dev/rpmb_dev.c
+++ b/trusty/utils/rpmb_dev/rpmb_dev.c
@@ -591,7 +591,7 @@
         return EXIT_SUCCESS;
     }
 
-    open_flags = O_RDWR;
+    open_flags = O_RDWR | O_SYNC;
     if (init) {
         open_flags |= O_CREAT | O_TRUNC;
     }