vfio-mdev: buffer overflow in ioctl()

This is a sample driver for documentation so the impact is probably
pretty low.  But we should check that bar_index is valid so we
don't write beyond the end of the mdev_state->region_info[] array.

Fixes: 9d1a546c53 ("docs: Sample driver to demonstrate how to use Mediated device framework.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Dan Carpenter 2017-01-07 09:28:40 +03:00 committed by Alex Williamson
parent 6ed0993a0b
commit 5c677869e0

View File

@ -1073,7 +1073,7 @@ int mtty_get_region_info(struct mdev_device *mdev,
{
unsigned int size = 0;
struct mdev_state *mdev_state;
int bar_index;
u32 bar_index;
if (!mdev)
return -EINVAL;
@ -1082,8 +1082,11 @@ int mtty_get_region_info(struct mdev_device *mdev,
if (!mdev_state)
return -EINVAL;
mutex_lock(&mdev_state->ops_lock);
bar_index = region_info->index;
if (bar_index >= VFIO_PCI_NUM_REGIONS)
return -EINVAL;
mutex_lock(&mdev_state->ops_lock);
switch (bar_index) {
case VFIO_PCI_CONFIG_REGION_INDEX: