Re: [PATCH] hugetlbfs: Fix integer overflow check in hugetlbfs_file_mmap()

[Alexey Dobriyan <adobriyan@xxxxxxxxx>]

> --- a/fs/hugetlbfs/inode.c
> +++ b/fs/hugetlbfs/inode.c
> @@ -157,7 +157,7 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma)
>  	vma_len = (loff_t)(vma->vm_end - vma->vm_start);
>  	len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
>  	/* check for overflow */
> -	if (len < vma_len)
> +	if (vma_len > LLONG_MAX - ((loff_t)vma->vm_pgoff << PAGE_SHIFT))
>  		return -EINVAL;

Proper fix is to make everything unsigned probably.