 int au1100fb_fb_mmap(struct fb_info *fbi, struct vm_area_struct *vma)
 {
 	struct au1100fb_device *fbdev;
	unsigned int len;
	unsigned long start=0, off;
 
 	fbdev = to_au1100fb_device(fbi);
 
	if (vma->vm_pgoff > (~0UL >> PAGE_SHIFT)) {
		return -EINVAL;
	}
	start = fbdev->fb_phys & PAGE_MASK;
	len = PAGE_ALIGN((start & ~PAGE_MASK) + fbdev->fb_len);
	off = vma->vm_pgoff << PAGE_SHIFT;
	if ((vma->vm_end - vma->vm_start + off) > len) {
		return -EINVAL;
	}
	off += start;
	vma->vm_pgoff = off >> PAGE_SHIFT;
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 	pgprot_val(vma->vm_page_prot) |= (6 << 9); //CCA=6
 
	if (io_remap_pfn_range(vma, vma->vm_start, off >> PAGE_SHIFT,
				vma->vm_end - vma->vm_start,
				vma->vm_page_prot)) {
		return -EAGAIN;
	}
	return 0;
 }

The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.