| Message ID | 1386685766-12201-1-git-send-email-luis.henriques@canonical.com |
|---|---|
| State | New |
| Headers | show |
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index e560f54..f3535d9 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -779,7 +779,11 @@ static struct dma_pte *pfn_to_dma_pte(struct dmar_domain *domain, int offset; BUG_ON(!domain->pgd); - BUG_ON(addr_width < BITS_PER_LONG && pfn >> addr_width); + + if (addr_width < BITS_PER_LONG && pfn >> addr_width) + /* Address beyond IOMMU's addressing capabilities. */ + return NULL; + parent = domain->pgd; while (level > 0) {
This is a note to let you know that I have just added a patch titled iommu/vt-d: Fixed interaction of VFIO_IOMMU_MAP_DMA with IOMMU to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From b314911abae9b0ad51e1efa080cc0e6b2b8d7757 Mon Sep 17 00:00:00 2001 From: Julian Stecklina <jsteckli@os.inf.tu-dresden.de> Date: Wed, 9 Oct 2013 10:03:52 +0200 Subject: iommu/vt-d: Fixed interaction of VFIO_IOMMU_MAP_DMA with IOMMU address limits commit f9423606ade08653dd8a43334f0a7fb45504c5cc upstream. 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 <jsteckli@os.inf.tu-dresden.de> Acked-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Joerg Roedel <joro@8bytes.org> Cc: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/iommu/intel-iommu.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) -- 1.8.3.2