Re: [PATCH] hugetlb: fix memoryleak in hugetlb_mcopy_atomic_pte

Mike Kravetz
2022-07-11T21:02:40Z

On 07/09/22 17:26, Miaohe Lin wrote:
> When alloc_huge_page fails, *pagep is set to NULL without put_page first.
> So the hugepage indicated by *pagep is leaked.
>
> Fixes: 8cc5fcbb5be8 ("mm, hugetlb: fix racy resv_huge_pages underflow on UFFDIO_COPY")
> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
> ---
> mm/hugetlb.c | 1 +
> 1 file changed, 1 insertion(+)

Thanks for finding and fixing!

Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
--
Mike Kravetz

>
> diff --git a/mm/hugetlb.c b/mm/hugetlb.c
> index 06c2d86b1ba3..598c37279fee 100644
> --- a/mm/hugetlb.c
> +++ b/mm/hugetlb.c
> @@ -5962,6 +5962,7 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
>
> page = alloc_huge_page(dst_vma, dst_addr, 0);
> if (IS_ERR(page)) {
> + put_page(*pagep);
> ret = -ENOMEM;
> *pagep = NULL;
> goto out;
> --
> 2.23.0
>