Android 4.4 Kitkat - Temporary root just to fix SD Card permissions

Recently, I've upgraded my phone to KitKat 4.4. But I wasn't aware this would restrict SD Card access for most apps as an unwanted side effect.

On rooted Android devices, this can easily be changed. Now, I've found an easy way to only temporary root the phone - even without rebooting and just to apply the fix. Afterwards, we will unroot immediately.
 
1. Install the "towelroot" app and run it:
https://towelroot.com/tr.apk  (from https://towelroot.com/ )

You should be rooted- without a reboot and all the other complicated rooting procedures of the past! WOW! Good job!

2. Install and run "SD KitKat Fixer" from the Play Store:
https://play.google.com/store/apps/details?id=jrummy.sdfix

3. "Un-rooting" again:
Open a shell window - I use SSHDroid on the phone and "putty" as a client on a Windows machine.
(adb, etc. should also work fine).

3a) OPTIONAL:verify the changes made by SD KitKat Fixer:

less /system/etc/permissions/platform.xml

You should see a section like this:

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

3b) Remove the "su" related stuff aka "unrooting".

su
mount -o rw,remount /system
#rm /system/bin/su
rm /system/xbin/su
rm /system/xbin/daemonsu
rm /system/etc/install-recovery.sh
mount -o ro,remount /system
exit

Note: the system partition may already be mounted rw., and remounting read-only as a last step may fail. No problem, as we are going to reboot anyways.

4. Reboot - DONE.

Tested on my S4 mini running Android 4.4.


Just to compare: This was the content of my /system/xbin folder right after using towelroot:

 $ ls -al /system/xbin
drwxr-xr-x    2 root     shell         4096 Jul 29 19:11 .
drwxr-xr-x   24 root     root          4096 Jan  9  2014 ..
-rwxr-xr-x    1 root     root        121260 Jul 29 19:11 daemonsu
-rwxr-xr-x    1 root     shell        59748 May 23 11:17 dexdump
-rwxr-xr-x    1 root     root        121260 Jul 29 19:11 su
-rwxr-xr-x    1 root     shell         5336 May 23 11:17 vril-dump

PS: I'm not afraid of a permanently rooted device at all, but some use cases limit the user to an official, non-rooted ROM - that's BYOD ;-)