vfio: checking of validity of user vaddr in vfio_dma_rw

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.

Fixes: 8d46c0cca5f4 ("vfio: introduce vfio_dma_rw to read/write a range of IOVAs")
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
Reported-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 85b32c3252829de7fb42b5fcb3c6ebde6e989555..aa501e826e703665796047f4f78cee2386a5a791 100644 (file)
--- 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);