From: Julian Stecklina Date: Wed, 9 Oct 2013 08:03:52 +0000 (+0200) Subject: iommu/vt-d: Fixed interaction of VFIO_IOMMU_MAP_DMA with IOMMU address limits X-Git-Tag: v3.13-rc1~79^2^4~2 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f9423606ade08653dd8a43334f0a7fb45504c5cc;p=pandora-kernel.git iommu/vt-d: Fixed interaction of VFIO_IOMMU_MAP_DMA with IOMMU address limits The BUG_ON in drivers/iommu/intel-iommu.c:785 can be triggered from userspace via VFIO by calling the VFIO_IOMMU_MAP_DMA ioctl on a vfio device with any address beyond the addressing capabilities of the IOMMU. The problem is that the ioctl code calls iommu_iova_to_phys before it calls iommu_map. iommu_map handles the case that it gets addresses beyond the addressing capabilities of its IOMMU. intel_iommu_iova_to_phys does not. This patch fixes iommu_iova_to_phys to return NULL for addresses beyond what the IOMMU can handle. This in turn causes the ioctl call to fail in iommu_map and (correctly) return EFAULT to the user with a helpful warning message in the kernel log. Signed-off-by: Julian Stecklina Acked-by: Alex Williamson Signed-off-by: Joerg Roedel --- Reading git-diff-tree failed