linux-kernel - Re: [PATCH] mm: fix racing of vb->va when kasan enabled

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: <CAGWkznE5cFfdtmQ2j57goWtpfPGYPsd5Oi3pvb9vcfifodR9OQ@mail.gmail.com>
Date:   Mon, 20 Jun 2022 19:23:34 +0800
From:   Zhaoyang Huang <huangzhaoyang@...il.com>
To:     Uladzislau Rezki <urezki@...il.com>
Cc:     "zhaoyang.huang" <zhaoyang.huang@...soc.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        "open list:MEMORY MANAGEMENT" <linux-mm@...ck.org>,
        LKML <linux-kernel@...r.kernel.org>,
        Ke Wang <ke.wang@...soc.com>, Christoph Hellwig <hch@....de>
Subject: Re: [PATCH] mm: fix racing of vb->va when kasan enabled

On Mon, Jun 20, 2022 at 6:44 PM Uladzislau Rezki <urezki@...il.com> wrote:
>
> > > >
> > > Is it easy to reproduce? If so could you please describe the steps? As i see
> > > the freeing of the "vb" is RCU safe whereas vb->va is not. But from the first
> > > glance i do not see how it can accessed twice. Hm..
> > It was raised from a monkey test on A13_k515 system and got 1/20 pcs
> > failed. IMO, vb->va which out of vmap_purge_lock protection could race
> > with a concurrent ra freeing within __purge_vmap_area_lazy.
> >
> Do you have exact steps how you run "monkey" test?
There are about 30+ kos inserted during startup which could be a
specific criteria for reproduction. Do you have doubts about the test
result or the solution?
>
> --
> Uladzislau Rezki