instead of calling __copy_to/from_user(), use copy_to_from_user() to ensure vaddr range is a valid user address range before accessing them. Cc: Kees Cook <keescook@xxxxxxxxxxxx> Fixes: 8d46c0cca5f4 ("vfio: introduce vfio_dma_rw to read/write a range of IOVAs") Signed-off-by: Yan Zhao <yan.y.zhao@xxxxxxxxx> --- drivers/vfio/vfio_iommu_type1.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index 3aefcc8e2933..fbc58284b333 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -2345,10 +2345,10 @@ static int vfio_iommu_type1_dma_rw_chunk(struct vfio_iommu *iommu, vaddr = dma->vaddr + offset; if (write) - *copied = __copy_to_user((void __user *)vaddr, data, + *copied = copy_to_user((void __user *)vaddr, data, count) ? 0 : count; else - *copied = __copy_from_user(data, (void __user *)vaddr, + *copied = copy_from_user(data, (void __user *)vaddr, count) ? 0 : count; if (kthread) unuse_mm(mm); -- 2.17.1