xen/gntdev: Fix off-by-one error when unmapping with holes

[ Upstream commit 951a010233 ]

If the requested range has a hole, the calculation of the number of
pages to unmap is off by one. Fix it.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ross Lagerwall 2018-01-09 12:10:21 +00:00 committed by Greg Kroah-Hartman
parent 197faf0c3a
commit 5aee2c142e

View file

@ -380,10 +380,8 @@ static int unmap_grant_pages(struct grant_map *map, int offset, int pages)
}
range = 0;
while (range < pages) {
if (map->unmap_ops[offset+range].handle == -1) {
range--;
if (map->unmap_ops[offset+range].handle == -1)
break;
}
range++;
}
err = __unmap_grant_pages(map, offset, range);