xen/gntdev: avoid out of bounds access in case of partial gntdev_mmap()
authorJuergen Gross <jgross@suse.com>
Wed, 25 Oct 2017 15:08:07 +0000 (17:08 +0200)
committerBoris Ostrovsky <boris.ostrovsky@oracle.com>
Wed, 25 Oct 2017 16:48:13 +0000 (12:48 -0400)
commit298d275d4d9bea3524ff4bc76678c140611d8a8d
tree4337329fdc85462328edb08a35f6c373c82ab6f1
parente1043a4bb9fce6cfc7d55c5767e429a18ac8c4eb
xen/gntdev: avoid out of bounds access in case of partial gntdev_mmap()

In case gntdev_mmap() succeeds only partially in mapping grant pages
it will leave some vital information uninitialized needed later for
cleanup. This will lead to an out of bounds array access when unmapping
the already mapped pages.

So just initialize the data needed for unmapping the pages a little bit
earlier.

Cc: <stable@vger.kernel.org>
Reported-by: Arthur Borsboom <arthurborsboom@gmail.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
drivers/xen/gntdev.c