[adb] copy db file with adb pull results in 'permission denied' error

$ adb shell
$su
# getenforce
Enforcing

now try

adb shell
su
chmod 777 /path/to/yout_file

exit from shell

open new CMD and try adb pull /path/to/yout_file

It will work fine now.

you'll have security problems because of this any application will be able to access your database.