Make toasts non-clickable
Since enforcement was only on client-side, in Toast class, an app could
use reflection (or other means) to make the Toast clickable. This is a
security vulnerability since it allows tapjacking, that is, intercept touch
events and do stuff like steal PINs and passwords.
This CL brings the enforcement to the system by applying flag
FLAG_NOT_TOUCHABLE.
Test: Working on CTS test
Test: Construct app that uses reflection to remove flag FLAG_NOT_TOUCHABLE and
log click events. Then:
1) Observe click events are logged without this CL.
2) Observer click events are not logged with this CL.
Bug: 128674520
Change-Id: Ic36585bc4f186e0224f5b687c49c0b3d9266838c
diff --git a/services/core/java/com/android/server/wm/DisplayPolicy.java b/services/core/java/com/android/server/wm/DisplayPolicy.java
index 10d48c4..a1d6df9 100644
--- a/services/core/java/com/android/server/wm/DisplayPolicy.java
+++ b/services/core/java/com/android/server/wm/DisplayPolicy.java
@@ -860,6 +860,8 @@
if (canToastShowWhenLocked(callingPid)) {
attrs.flags |= WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED;
}
+ // Toasts can't be clickable
+ attrs.flags |= WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE;
break;
}