From: Christian A. Ehrhardt lk@c--e.de
commit 909290786ea335366e21d7f1ed5812b90f2f0a92 upstream.
When mmaping an extra device region verify that the region index derived from the mmap offset is valid.
Fixes: a15b1883fee1 ("vfio_pci: Allow mapping extra regions") Cc: stable@vger.kernel.org Signed-off-by: Christian A. Ehrhardt lk@c--e.de Message-Id: 20210412214124.GA241759@lisa.in-ulm.de Reviewed-by: David Gibson david@gibson.dropbear.id.au Reviewed-by: Cornelia Huck cohuck@redhat.com Signed-off-by: Alex Williamson alex.williamson@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/vfio/pci/vfio_pci.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
--- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -1658,6 +1658,8 @@ static int vfio_pci_mmap(void *device_da
index = vma->vm_pgoff >> (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT);
+ if (index >= VFIO_PCI_NUM_REGIONS + vdev->num_regions) + return -EINVAL; if (vma->vm_end < vma->vm_start) return -EINVAL; if ((vma->vm_flags & VM_SHARED) == 0) @@ -1666,7 +1668,7 @@ static int vfio_pci_mmap(void *device_da int regnum = index - VFIO_PCI_NUM_REGIONS; struct vfio_pci_region *region = vdev->region + regnum;
- if (region && region->ops && region->ops->mmap && + if (region->ops && region->ops->mmap && (region->flags & VFIO_REGION_INFO_FLAG_MMAP)) return region->ops->mmap(vdev, region, vma); return -EINVAL;