linux-kernel - Re: [PATCH] riscv: Allow PROT

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: <CALE4mHpz6DpV+jq2uqic7DCqv3a0qcYqov8+wjhZSVx5-2nkEw@mail.gmail.com>
Date:   Thu, 8 Sep 2022 14:14:08 -0400
From:   Andrew Bresticker <abrestic@...osinc.com>
To:     SS JieJi <c141028@...il.com>
Cc:     Palmer Dabbelt <palmer@...belt.com>,
        Paul Walmsley <paul.walmsley@...ive.com>,
        Atish Patra <atishp@...shpatra.org>,
        Celeste Liu <coelacanthus@...look.com>,
        dram <dramforever@...e.com>, linux-riscv@...ts.infradead.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] riscv: Allow PROT_WRITE-only mmap()

On Thu, Sep 8, 2022 at 1:28 PM SS JieJi <c141028@...il.com> wrote:
>
> > https://fars.ee/1sPb, showing *inconsistent* read results on -r- pages
> > before/after a write attempt performed by the kernel.
>
> That said, maybe prohibit mmap-ing -w- pages is not the best fix for
> this issue. If -w- pages are irreplaceable for some use cases (and
> hence need to be allowed), I'd suggest at least we need to re-fix the
> read result inconsistency issue somewhere else despite simply
> reverting the patch.

Ah, this is because do_page_fault() also needs to be made aware of
write-implying-read. Will send a v2 shortly.

-Andrew

>
> Yours, Pan Ruizhe