From 909290786ea335366e21d7f1ed5812b90f2f0a92 Mon Sep 17 00:00:00 2001 From: "Christian A. Ehrhardt" Date: Mon, 12 Apr 2021 23:41:24 +0200 Subject: [PATCH] vfio/pci: Add missing range check in vfio_pci_mmap 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 Message-Id: <20210412214124.GA241759@lisa.in-ulm.de> Reviewed-by: David Gibson Reviewed-by: Cornelia Huck Signed-off-by: Alex Williamson --- drivers/vfio/pci/vfio_pci.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c index 65e7e6b44578..5023e23db3bc 100644 --- a/drivers/vfio/pci/vfio_pci.c +++ b/drivers/vfio/pci/vfio_pci.c @@ -1656,6 +1656,8 @@ static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma) 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) @@ -1664,7 +1666,7 @@ static int vfio_pci_mmap(void *device_data, struct vm_area_struct *vma) 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;