linux-kernel - Re: [PATCH net V3] virtio-net: fix the race between refill work and close

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]

Date:   Thu, 30 Jun 2022 21:03:44 -0700
From:   Jakub Kicinski <kuba@...nel.org>
To:     Jason Wang <jasowang@...hat.com>
Cc:     mst@...hat.com, davem@...emloft.net, edumazet@...gle.com,
        pabeni@...hat.com, virtualization@...ts.linux-foundation.org,
        netdev@...r.kernel.org, linux-kernel@...r.kernel.org,
        xuanzhuo@...ux.alibaba.com
Subject: Re: [PATCH net V3] virtio-net: fix the race between refill work and
 close

On Fri,  1 Jul 2022 10:06:55 +0800 Jason Wang wrote:
> We try using cancel_delayed_work_sync() to prevent the work from
> enabling NAPI. This is insufficient since we don't disable the source
> of the refill work scheduling. This means an NAPI poll callback after
> cancel_delayed_work_sync() can schedule the refill work then can
> re-enable the NAPI that leads to use-after-free [1].
> 
> Since the work can enable NAPI, we can't simply disable NAPI before
> calling cancel_delayed_work_sync(). So fix this by introducing a
> dedicated boolean to control whether or not the work could be
> scheduled from NAPI.

Hm, does not apply cleanly to net or Linus's tree.