1 files changed, 31 insertions, 10 deletions

diff --git a/drivers/uio/uio.c b/drivers/uio/uio.c
index b645c47501b..2d57a00dc17 100644
--- a/drivers/uio/uio.c
+++ b/drivers/uio/uio.c
@@ -630,36 +630,57 @@ static int uio_vma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 	return 0;
 }
 
-static const struct vm_operations_struct uio_vm_ops = {
+static const struct vm_operations_struct uio_logical_vm_ops = {
 	.open = uio_vma_open,
 	.close = uio_vma_close,
 	.fault = uio_vma_fault,
 };
 
+static int uio_mmap_logical(struct vm_area_struct *vma)
+{
+	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
+	vma->vm_ops = &uio_logical_vm_ops;
+	uio_vma_open(vma);
+	return 0;
+}
+
+static const struct vm_operations_struct uio_physical_vm_ops = {
+#ifdef CONFIG_HAVE_IOREMAP_PROT
+	.access = generic_access_phys,
+#endif
+};
+
 static int uio_mmap_physical(struct vm_area_struct *vma)
 {
 	struct uio_device *idev = vma->vm_private_data;
 	int mi = uio_find_mem_index(vma);
+	struct uio_mem *mem;
 	if (mi < 0)
 		return -EINVAL;
+	mem = idev->info->mem + mi;
 
+	if (vma->vm_end - vma->vm_start > mem->size)
+		return -EINVAL;
+
+	vma->vm_ops = &uio_physical_vm_ops;
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 
+	/*
+	 * We cannot use the vm_iomap_memory() helper here,
+	 * because vma->vm_pgoff is the map index we looked
+	 * up above in uio_find_mem_index(), rather than an
+	 * actual page offset into the mmap.
+	 *
+	 * So we just do the physical mmap without a page
+	 * offset.
+	 */
 	return remap_pfn_range(vma,
 			       vma->vm_start,
-			       idev->info->mem[mi].addr >> PAGE_SHIFT,
+			       mem->addr >> PAGE_SHIFT,
 			       vma->vm_end - vma->vm_start,
 			       vma->vm_page_prot);
 }
 
-static int uio_mmap_logical(struct vm_area_struct *vma)
-{
-	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
-	vma->vm_ops = &uio_vm_ops;
-	uio_vma_open(vma);
-	return 0;
-}
-
 static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
 {
 	struct uio_listener *listener = filep->private_data;