| Message ID | 1481048814-29752-1-git-send-email-kwankhede@nvidia.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, 6 Dec 2016 23:56:54 +0530 Kirti Wankhede <kwankhede@nvidia.com> wrote: > Passing zero for the size to vfio_find_dma() isn't compatible with > matching the start address of an existing vfio_dma. Doing so triggers a > corner case. In vfio_find_dma(), when the start address is equal to > dma->iova and size is 0, check for the end of search range makes it to > take wrong side of RB-tree. That fails the search even though the address > is present in mapped dma ranges. Due to this, in vfio_dma_do_unmap(), > while checking boundary conditions, size should be set to 1 for verifying > start address of unmap range. > vfio_find_dma() is also used to verify last address in unmap range with > size = 0, but in that case address to be searched is calculated with > size - 1 and so it works correctly. I think this last sentence should actually read "start + size - 1", or at least that makes it more understandable for me. I'll make that change and apply these. Thanks, Alex > Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> > Signed-off-by: Neo Jia <cjia@nvidia.com> > --- > 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 a28fbddb505c..8e9e94ccb2ff 100644 > --- a/drivers/vfio/vfio_iommu_type1.c > +++ b/drivers/vfio/vfio_iommu_type1.c > @@ -826,7 +826,7 @@ again: > * mappings within the range. > */ > if (iommu->v2) { > - dma = vfio_find_dma(iommu, unmap->iova, 0); > + dma = vfio_find_dma(iommu, unmap->iova, 1); > if (dma && dma->iova != unmap->iova) { > ret = -EINVAL; > goto unlock;
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index a28fbddb505c..8e9e94ccb2ff 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -826,7 +826,7 @@ again: * mappings within the range. */ if (iommu->v2) { - dma = vfio_find_dma(iommu, unmap->iova, 0); + dma = vfio_find_dma(iommu, unmap->iova, 1); if (dma && dma->iova != unmap->iova) { ret = -EINVAL; goto unlock;