[PATCH v13 19/20] vfio/type1, arm64: untag user pointers in vaddr_get_pfn
From: Andrey Konovalov <hidden>
Date: 2019-03-20 14:53:09
Also in:
bpf, linux-arch, linux-kselftest, linux-media, linux-mm, lkml
Subsystem:
the rest, vfio driver · Maintainers:
Linus Torvalds, Alex Williamson
This patch is a part of a series that extends arm64 kernel ABI to allow to pass tagged user pointers (with the top byte set to something else other than 0x00) as syscall arguments. vaddr_get_pfn() uses provided user pointers for vma lookups, which can only by done with untagged pointers. Untag user pointers in this function. Signed-off-by: Andrey Konovalov <redacted> --- drivers/vfio/vfio_iommu_type1.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 73652e21efec..e556caa64f83 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c@@ -376,6 +376,8 @@ static int vaddr_get_pfn(struct mm_struct *mm, unsigned long vaddr, down_read(&mm->mmap_sem); + vaddr = untagged_addr(vaddr); + vma = find_vma_intersection(mm, vaddr, vaddr + 1); if (vma && vma->vm_flags & VM_PFNMAP) {
--
2.21.0.225.g810b269d1ac-goog