linux-kernel - Re: [PULL] vhost: cleanups and fixes

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] [day] [month] [year] [list]

Message-ID: <20181130145527-mutt-send-email-mst@kernel.org>
Date:   Fri, 30 Nov 2018 14:55:38 -0500
From:   "Michael S. Tsirkin" <mst@...hat.com>
To:     Bijan Mottahedeh <bijan.mottahedeh@...cle.com>
Cc:     Linus Torvalds <torvalds@...ux-foundation.org>,
        Kees Cook <keescook@...omium.org>, kvm@...r.kernel.org,
        virtualization@...ts.linux-foundation.org, netdev@...r.kernel.org,
        Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
        Andrew Morton <akpm@...ux-foundation.org>, gedwards@....com,
        joe@...ches.com, lenaic@...ard.fr, liang.z.li@...el.com,
        mhocko@...nel.org, mhocko@...e.com, stefanha@...hat.com,
        wei.w.wang@...el.com
Subject: Re: [PULL] vhost: cleanups and fixes

On Fri, Nov 30, 2018 at 11:01:03AM -0800, Bijan Mottahedeh wrote:
> On 11/30/2018 5:44 AM, Michael S. Tsirkin wrote:
> > On Thu, Nov 01, 2018 at 04:06:19PM -0700, Linus Torvalds wrote:
> > > On Thu, Nov 1, 2018 at 4:00 PM Kees Cook <keescook@...omium.org> wrote:
> > > > +       memset(&rsp, 0, sizeof(rsp));
> > > > +       rsp.response = VIRTIO_SCSI_S_FUNCTION_REJECTED;
> > > > +       resp = vq->iov[out].iov_base;
> > > > +       ret = __copy_to_user(resp, &rsp, sizeof(rsp));
> > > > 
> > > > Is it actually safe to trust that iov_base has passed an earlier
> > > > access_ok() check here? Why not just use copy_to_user() instead?
> > > Good point.
> > > 
> > > We really should have removed those double-underscore things ages ago.
> > > 
> > > Also, apart from the address, what about the size? Wouldn't it be
> > > better to use copy_to_iter() rather than implement it badly by hand?
> > > 
> > >                 Linus
> > Bijan can you respond please?
> > Are you going to look into this and convert code to copy_to_iter?
> > I don't think we should release Linux like this, so if you don't
> > have the time I'd rather revert for now and you can look
> > into reposting for the next release.
> > 
> > Thanks,
> > 
> 
> Sure, will do.  Can I send an individual patch for the fix to
> vhost_scsi_send_tmf_reject()?
> 
> Thanks.
> 
> --bijan

Please go ahead.

-- 
MST