| Message ID | 154696559827.32763.11706407320970225120.stgit@gimli.home (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | vfio/type1: Fix unmap overflow off-by-one | expand |
Yeah, sorry about that.
Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>
regards,
dan carpenter
On Tue, Jan 08, 2019 at 09:40:06AM -0700, Alex Williamson wrote: > The below referenced commit adds a test for integer overflow, but in > doing so prevents the unmap ioctl from ever including the last page of > the address space. Subtract one to compare to the last address of the > unmap to avoid the overflow and wrap-around. > > Fixes: 71a7d3d78e3c ("vfio/type1: silence integer overflow warning") > Link: https://bugzilla.redhat.com/show_bug.cgi?id=1662291 > Cc: Dan Carpenter <dan.carpenter@oracle.com> > Reported-by: Pei Zhang <pezhang@redhat.com> > Debugged-by: Peter Xu <peterx@redhat.com> > Signed-off-by: Alex Williamson <alex.williamson@redhat.com> I tested this against the QEMU reboot error and it works. Reviewed-by: Peter Xu <peterx@redhat.com> Tested-by: Peter Xu <peterx@redhat.com> Thanks, > --- > drivers/vfio/vfio_iommu_type1.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c > index 7651cfb14836..73652e21efec 100644 > --- a/drivers/vfio/vfio_iommu_type1.c > +++ b/drivers/vfio/vfio_iommu_type1.c > @@ -878,7 +878,7 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, > return -EINVAL; > if (!unmap->size || unmap->size & mask) > return -EINVAL; > - if (unmap->iova + unmap->size < unmap->iova || > + if (unmap->iova + unmap->size - 1 < unmap->iova || > unmap->size > SIZE_MAX) > return -EINVAL; > >
On Tue, 08 Jan 2019 09:40:06 -0700 Alex Williamson <alex.williamson@redhat.com> wrote: > The below referenced commit adds a test for integer overflow, but in > doing so prevents the unmap ioctl from ever including the last page of > the address space. Subtract one to compare to the last address of the > unmap to avoid the overflow and wrap-around. > > Fixes: 71a7d3d78e3c ("vfio/type1: silence integer overflow warning") > Link: https://bugzilla.redhat.com/show_bug.cgi?id=1662291 > Cc: Dan Carpenter <dan.carpenter@oracle.com> > Reported-by: Pei Zhang <pezhang@redhat.com> > Debugged-by: Peter Xu <peterx@redhat.com> > Signed-off-by: Alex Williamson <alex.williamson@redhat.com> > --- > drivers/vfio/vfio_iommu_type1.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) Reviewed-by: Cornelia Huck <cohuck@redhat.com>
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 7651cfb14836..73652e21efec 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -878,7 +878,7 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu, return -EINVAL; if (!unmap->size || unmap->size & mask) return -EINVAL; - if (unmap->iova + unmap->size < unmap->iova || + if (unmap->iova + unmap->size - 1 < unmap->iova || unmap->size > SIZE_MAX) return -EINVAL;
The below referenced commit adds a test for integer overflow, but in doing so prevents the unmap ioctl from ever including the last page of the address space. Subtract one to compare to the last address of the unmap to avoid the overflow and wrap-around. Fixes: 71a7d3d78e3c ("vfio/type1: silence integer overflow warning") Link: https://bugzilla.redhat.com/show_bug.cgi?id=1662291 Cc: Dan Carpenter <dan.carpenter@oracle.com> Reported-by: Pei Zhang <pezhang@redhat.com> Debugged-by: Peter Xu <peterx@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com> --- drivers/vfio/vfio_iommu_type1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)