diff --git a/services/core/java/com/android/server/StorageManagerService.java b/services/core/java/com/android/server/StorageManagerService.java
index a04f25b..ffdaa65 100644
--- a/services/core/java/com/android/server/StorageManagerService.java
+++ b/services/core/java/com/android/server/StorageManagerService.java
@@ -3941,8 +3941,12 @@
             final boolean hasMtp = mIPackageManager.checkUidPermission(ACCESS_MTP, uid) ==
                     PERMISSION_GRANTED;
             if (mIsFuseEnabled && hasMtp) {
-                // The process hosting the MTP server should be able to write in Android/
-                return Zygote.MOUNT_EXTERNAL_ANDROID_WRITABLE;
+                ApplicationInfo ai = mIPackageManager.getApplicationInfo(packageName,
+                        0, UserHandle.getUserId(uid));
+                if (ai.isSignedWithPlatformKey()) {
+                    // Platform processes hosting the MTP server should be able to write in Android/
+                    return Zygote.MOUNT_EXTERNAL_ANDROID_WRITABLE;
+                }
             }
 
             // Determine if caller is holding runtime permission