Backporting commit 19be0eaffa [mm: remove gup_flags FOLL_WRITE games
from __get_user_pages()] to address the dirtycow exploit.
(From OE-Core rev: 8470ea4cfd5fca4c9573e39c7c3486aeb310990a)
Signed-off-by: Bruce Ashfield <bruce.ashfield@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>