linux-kernel - Re: [PATCH] hugetlb: fix hugetlb cgroup refcounting during mremap

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20211115131633.81e1879e36aed4a0290e6f0c@linux-foundation.org>
Date:   Mon, 15 Nov 2021 13:16:33 -0800
From:   Andrew Morton <akpm@...ux-foundation.org>
To:     Bui Quang Minh <minhquangbui99@...il.com>
Cc:     Mike Kravetz <mike.kravetz@...cle.com>,
        Miaohe Lin <linmiaohe@...wei.com>,
        Michal Hocko <mhocko@...e.com>,
        Muchun Song <songmuchun@...edance.com>,
        Mina Almasry <almasrymina@...gle.com>,
        linux-kernel@...r.kernel.org, linux-mm@...ck.org
Subject: Re: [PATCH] hugetlb: fix hugetlb cgroup refcounting during mremap

On Sat, 13 Nov 2021 22:44:10 +0700 Bui Quang Minh <minhquangbui99@...il.com> wrote:

> When hugetlb_vm_op_open() is called during copy_vma(), we may take the
> reference to resv_map->css. Later, when clearing the reservation pointer
> of old_vma after transferring it to new_vma, we forget to drop the
> reference to resv_map->css. This leads to a reference leak of css.
> 
> Fixes this by adding a check to drop reservation css  reference in
> clear_vma_resv_huge_pages()

Thanks.  I added cc:stable to this (550a7d60bd5e35a was merged a year
ago) and I've queued it for 5.16-rc2, pending suitable reviewer feedback.