diff --git a/drivers/usb/mon/mon_bin.c b/drivers/usb/mon/mon_bin.c
index f48a23adbc35..094e812e9e69 100644
--- a/drivers/usb/mon/mon_bin.c
+++ b/drivers/usb/mon/mon_bin.c
@@ -1268,6 +1268,11 @@ static int mon_bin_mmap(struct file *filp, struct vm_area_struct *vma)
 {
 	/* don't do anything here: "fault" will set up page table entries */
 	vma->vm_ops = &mon_bin_vm_ops;
+
+	if (vma->vm_flags & VM_WRITE)
+		return -EPERM;
+
+	vma->vm_flags &= ~VM_MAYWRITE;
 	vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 	vma->vm_private_data = filp->private_data;
 	mon_bin_vma_open(vma);