I Tried it a bunch of times on .621 and could not obtain root.
Data:
> su
> /system/xbin/su
> mount -o remount,rw /dev/block/mtdblock3 /system
> if [ -e /data/local/12m.bak ];
> then
> rm /data/local/12m.bak
> fi
> exit
> exit
$ su
su: permission denied
$ /system/xbin/su
/system/xbin/su: not found
$ mount -o remount,rw /dev/block/mtdblock3 /system
if [ -e /data/local/12m.bak ];
mount: Operation not permitted
$ if [ -e /data/local/12m.bak ];
> then
> rm /data/local/12m.bak
> fi
exit
$ exit
(success)
> mv /data/local/12m /data/local/12m.bak
(success)
> ln -s /data /data/local/12m
(success)
> su
> /system/xbin/su
> mount -o remount,rw /dev/block/mtdblock3 /system
> if [ -e /data/local/12m ];
> then
> rm /data/local/12m
> fi
> exit
> exit
$ su
mount -o remount,rw /dev/block/mtdblock3 /system
su: permission denied
$ /system/xbin/su
/system/xbin/su: not found
$ mount -o remount,rw /dev/block/mtdblock3 /system
if [ -e /data/local/12m ];
mount: Operation not permitted
$ if [ -e /data/local/12m ];
> then
> rm /data/local/12m
> fi
exit
$ exit
(success)
> mv /data/local/12m.bak /data/local/12m
(success)
> su
> /system/xbin/su
> mount -o remount,rw /dev/block/mtdblock3 /system
> if [ -e /data/local.prop.bak ];
> then
> rm /data/local.prop.bak
> fi
> exit
> exit
su
/system/xbin/su
$ su
su: permission denied
$ /system/xbin/su
/system/xbin/su: not found
$ mount -o remount,rw /dev/block/mtdblock3 /system
mount: Operation not permitted
$ if [ -e /data/local.prop.bak ];
> then
> rm /data/local.prop.bak
> fi
$ exit
(success)
> mv /data/local.prop /data/local.prop.bak
> echo "ro.sys.atvc_allow_netmon_usb=0" > /data/local.prop
> echo "ro.sys.atvc_allow_netmon_ih=0" >> /data/local.prop
> echo "ro.sys.atvc_allow_res_core=0" >> /data/local.prop
> echo "ro.sys.atvc_allow_res_panic=0" >> /data/local.prop
> echo "ro.sys.atvc_allow_all_adb=1" >> /data/local.prop
> echo "ro.sys.atvc_allow_all_core=0" >> /data/local.prop
> echo "ro.sys.atvc_allow_efem=0" >> /data/local.prop
> echo "ro.sys.atvc_allow_bp_log=0" >> /data/local.prop
> echo "ro.sys.atvc_allow_ap_mot_log=0" >> /data/local.prop
> echo "ro.sys.atvc_allow_gki_log=0" >> /data/local.prop
mv /data/local.prop /data/local.prop.bak
echo "ro.sys.atvc_allow_netmon_usb=0" > /data/local.prop
$ mv /data/local.prop /data/local.prop.bak
failed on '/data/local.prop' - Permission denied
echo "ro.sys.atvc_allow_netmon_ih=0" >> /data/local.prop
$ echo "ro.sys.atvc_allow_netmon_usb=0" > /data/local.prop
cannot create /data/local.prop: permission denied
$ echo "ro.sys.atvc_allow_netmon_ih=0" >> /data/local.prop
cannot create /data/local.prop: permission denied
$ echo "ro.sys.atvc_allow_res_core=0" >> /data/local.prop
cannot create /data/local.prop: permission denied
$ echo "ro.sys.atvc_allow_res_panic=0" >> /data/local.prop
cannot create /data/local.prop: permission denied
$ echo "ro.sys.atvc_allow_all_adb=1" >> /data/local.prop
cannot create /data/local.prop: permission denied
$ echo "ro.sys.atvc_allow_all_core=0" >> /data/local.prop
cannot create /data/local.prop: permission denied
$ echo "ro.sys.atvc_allow_efem=0" >> /data/local.prop
cannot create /data/local.prop: permission denied
$ echo "ro.sys.atvc_allow_bp_log=0" >> /data/local.prop
cannot create /data/local.prop: permission denied
$ echo "ro.sys.atvc_allow_ap_mot_log=0" >> /data/local.prop
cannot create /data/local.prop: permission denied
$ echo "ro.sys.atvc_allow_gki_log=0" >> /data/local.prop
cannot create /data/local.prop: permission denied
$ exit
(success)