SD Card no writing permission in FP2

Regarding the file show in this post : SD Card no writing permission in FP2 - #40 by barney

One should not forget to include the :

<?xml version="1.0" encoding="utf-8"?>

At the begining, followed by a :

<permissions>

Opening tag, closed at the file ending by a :

</permissions>

(don’t miss the plural form).

<?xml version="1.0" encoding="utf-8"?>

<permissions>
<!-- ================================================================== -->
<!-- ================================================================== -->
<!-- ================================================================== -->

<!-- The following tags are associating low-level group IDs with
     permission names.  By specifying such a mapping, you are saying
     that any application process granted the given permission will
     also be running with the given group ID attached to its process,
     so it can perform any filesystem (read, write, execute) operations
     allowed for that group. -->

<permission name="android.permission.BLUETOOTH_ADMIN" >
    <group gid="net_bt_admin" />
</permission>

<permission name="android.permission.BLUETOOTH" >
    <group gid="net_bt" />
</permission>

<permission name="android.permission.BLUETOOTH_STACK" >
    <group gid="net_bt_stack" />
</permission>

<permission name="android.permission.NET_TUNNELING" >
    <group gid="vpn" />
</permission>

<permission name="android.permission.INTERNET" >
    <group gid="inet" />
</permission>

<permission name="android.permission.READ_LOGS" >
    <group gid="log" />
</permission>

<permission name="android.permission.READ_EXTERNAL_STORAGE" >
    <group gid="sdcard_r" />
</permission>

<permission name="android.permission.WRITE_EXTERNAL_STORAGE" >
    <group gid="sdcard_r" />
    <group gid="sdcard_rw" />
</permission>

<permission name="android.permission.ACCESS_ALL_EXTERNAL_STORAGE" >
    <group gid="sdcard_r" />
    <group gid="sdcard_rw" />
    <group gid="sdcard_all" />
</permission>

<permission name="android.permission.WRITE_MEDIA_STORAGE" >
    <group gid="media_rw" />
</permission>

<permission name="android.permission.ACCESS_MTP" >
    <group gid="mtp" />
</permission>

<permission name="android.permission.NET_ADMIN" >
    <group gid="net_admin" />
</permission>

<!-- The group that /cache belongs to, linked to the permission
     set on the applications that can access /cache -->
<permission name="android.permission.ACCESS_CACHE_FILESYSTEM" >
    <group gid="cache" />
</permission>

<!-- RW permissions to any system resources owned by group 'diag'.
     This is for carrier and manufacture diagnostics tools that must be
     installable from the framework. Be careful. -->
<permission name="android.permission.DIAGNOSTIC" >
    <group gid="input" />
    <group gid="diag" />
</permission>

<!-- Group that can read detailed network usage statistics -->
<permission name="android.permission.READ_NETWORK_USAGE_HISTORY">
    <group gid="net_bw_stats" />
</permission>

<!-- Group that can modify how network statistics are accounted -->
<permission name="android.permission.MODIFY_NETWORK_ACCOUNTING">
    <group gid="net_bw_acct" />
</permission>

<permission name="android.permission.LOOP_RADIO" >
    <group gid="loop_radio" />
</permission>

<!-- Hotword training apps sometimes need a GID to talk with low-level
     hardware; give them audio for now until full HAL support is added. -->
<permission name="android.permission.MANAGE_VOICE_KEYPHRASES">
    <group gid="audio" />
</permission>

<permission name="android.permission.ACCESS_FM_RADIO" >
    <group gid="media" />
</permission>

<!-- ================================================================== -->
<!-- ================================================================== -->
<!-- ================================================================== -->

<!-- The following tags are assigning high-level permissions to specific
     user IDs.  These are used to allow specific core system users to
     perform the given operations with the higher-level framework.  For
     example, we give a wide variety of permissions to the shell user
     since that is the user the adb shell runs under and developers and
     others should have a fairly open environment in which to
     interact with the system. -->

<assign-permission name="android.permission.MODIFY_AUDIO_SETTINGS" uid="media" />
<assign-permission name="android.permission.ACCESS_SURFACE_FLINGER" uid="media" />
<assign-permission name="android.permission.WAKE_LOCK" uid="media" />
<assign-permission name="android.permission.UPDATE_DEVICE_STATS" uid="media" />
<assign-permission name="android.permission.UPDATE_APP_OPS_STATS" uid="media" />

<assign-permission name="android.permission.ACCESS_SURFACE_FLINGER" uid="graphics" />

<!-- This is a list of all the libraries available for application
     code to link against. -->

<library name="android.test.runner"
        file="/system/framework/android.test.runner.jar" />
<library name="javax.obex"
        file="/system/framework/javax.obex.jar"/>
<library name="javax.btobex"
        file="/system/framework/javax.btobex.jar"/>

<!-- These are the standard packages that are white-listed to always have internet
     access while in power save mode, even if they aren't in the foreground. -->
<allow-in-power-save package="com.android.providers.downloads" />
</permissions>

(I’ll keep editing this post to present a correct ‘stock’ platform.xml file)

Files seem equivalent but the good way of doing it is to get a fresh one this way :

If you need the file “fresh” again (but what you show looks okay, it’s just the file without changes), you can just download the bin blob and unpack it. You will find the “fresh” file under: ./vendor/qcom/proprietary/target/product/FP2/system/etc/permissions/platform.xml