BugLink: http://bugs.launchpad.net/bugs/1765010

[ Upstream commit 146180c0 ]

The "DIV_ROUND_UP(size, PAGE_SIZE)" operation can overflow if "size" is
more than ULLONG_MAX - PAGE_SIZE.

Link: http://lkml.kernel.org/r/20170322111950.GA11279@mwandaSigned-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Jorgen Hansen <jhansen@vmware.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>