linux-kernel - Re: [PATCH 1/2] mm/vmalloc: Add a safer version of find_vm

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: <CAEXW_YRvCQP+eoWmbnEwXs925xXQYPDuCp+iyzWeo8HY9dq+Ew@mail.gmail.com>
Date:   Wed, 30 Aug 2023 08:17:18 -0400
From:   Joel Fernandes <joel@...lfernandes.org>
To:     Matthew Wilcox <willy@...radead.org>
Cc:     linux-kernel@...r.kernel.org,
        Andrew Morton <akpm@...ux-foundation.org>,
        Uladzislau Rezki <urezki@...il.com>,
        Christoph Hellwig <hch@...radead.org>,
        Lorenzo Stoakes <lstoakes@...il.com>,
        Zhen Lei <thunder.leizhen@...weicloud.com>,
        "Paul E . McKenney" <paulmck@...nel.org>, rcu@...r.kernel.org,
        Zqiang <qiang.zhang1211@...il.com>, linux-mm@...ck.org
Subject: Re: [PATCH 1/2] mm/vmalloc: Add a safer version of find_vm_area() for debug

On Wed, Aug 30, 2023 at 8:08 AM Matthew Wilcox <willy@...radead.org> wrote:
>
> On Wed, Aug 30, 2023 at 11:03:59AM +0000, Joel Fernandes (Google) wrote:
> > It is unsafe to dump vmalloc area information when trying to do so from
> > some contexts. Add a safer trylock version of the same function to do a
> > best-effort VMA finding and use it from vmalloc_dump_obj().
> >
> > Reported-by: Zhen Lei <thunder.leizhen@...weicloud.com>
> > Cc: Paul E. McKenney <paulmck@...nel.org>
> > Cc: rcu@...r.kernel.org
> > Cc: Zqiang <qiang.zhang1211@...il.com>
> > Signed-off-by: Joel Fernandes (Google) <joel@...lfernandes.org>
>
> Reviewed-by: Matthew Wilcox (Oracle) <willy@...radead.org>

Thanks!

> I once started writing something similar, but got distracted and the
> immediate problem got solved a different way.
>
> It does make me wonder if we couldn't make this tree RCU-safe, but
> that's obviously a much larger job.

Yes, that would be nice.

 - Joel