linux-kernel - Re: [PATCH mm-unstable fix] mm: userfaultfd: check for start + len overflow in validate

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: <CAOUHufbPN2Zh53-YOJo8r+sRuXMt4Oav1Py6wWJgGA3aWRNvfQ@mail.gmail.com>
Date:   Thu, 10 Aug 2023 13:30:20 -0600
From:   Yu Zhao <yuzhao@...gle.com>
To:     Axel Rasmussen <axelrasmussen@...gle.com>
Cc:     Alexander Viro <viro@...iv.linux.org.uk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Brian Geffon <bgeffon@...gle.com>,
        Christian Brauner <brauner@...nel.org>,
        David Hildenbrand <david@...hat.com>,
        Gaosheng Cui <cuigaosheng1@...wei.com>,
        Huang Ying <ying.huang@...el.com>,
        Hugh Dickins <hughd@...gle.com>,
        James Houghton <jthoughton@...gle.com>,
        Jiaqi Yan <jiaqiyan@...gle.com>,
        Jonathan Corbet <corbet@....net>,
        Kefeng Wang <wangkefeng.wang@...wei.com>,
        "Liam R. Howlett" <Liam.Howlett@...cle.com>,
        Miaohe Lin <linmiaohe@...wei.com>,
        Mike Kravetz <mike.kravetz@...cle.com>,
        "Mike Rapoport (IBM)" <rppt@...nel.org>,
        Muchun Song <muchun.song@...ux.dev>,
        Nadav Amit <namit@...are.com>,
        Naoya Horiguchi <naoya.horiguchi@....com>,
        Peter Xu <peterx@...hat.com>,
        Ryan Roberts <ryan.roberts@....com>,
        Shuah Khan <shuah@...nel.org>,
        Steven Barrett <steven@...uorix.net>,
        Suleiman Souhlal <suleiman@...gle.com>,
        Suren Baghdasaryan <surenb@...gle.com>,
        "T.J. Alumbaugh" <talumbau@...gle.com>,
        ZhangPeng <zhangpeng362@...wei.com>, linux-doc@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-fsdevel@...r.kernel.org,
        linux-mm@...ck.org, linux-kselftest@...r.kernel.org
Subject: Re: [PATCH mm-unstable fix] mm: userfaultfd: check for start + len
 overflow in validate_range: fix

On Thu, Aug 10, 2023 at 1:21 PM Axel Rasmussen <axelrasmussen@...gle.com> wrote:
>
> A previous fixup to this commit fixed one issue, but introduced another:
> we're now overly strict when validating the src address for UFFDIO_COPY.
>
> Most of the validation in validate_range is useful to apply to src as
> well as dst, but page alignment is only a requirement for dst, not src.
> So, split the function up so src can use an "unaligned" variant, while
> still allowing us to share the majority of the code between the
> different cases.
>
> Reported-by: Ryan Roberts <ryan.roberts@....com>
> Closes: https://lore.kernel.org/linux-mm/8fbb5965-28f7-4e9a-ac04-1406ed8fc2d4@arm.com/T/#t
> Signed-off-by: Axel Rasmussen <axelrasmussen@...gle.com>

Reviewed-by:  Yu Zhao <yuzhao@...gle.com>