linux-kernel - RE: [PATCH 1/1] Drivers: scsi: storvsc: Don't pass ATA

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: <6E21E5352C11B742B20C142EB499E0481B74B90D@TK5EX14MBXC126.redmond.corp.microsoft.com>
Date:	Mon, 5 Mar 2012 02:29:11 +0000
From:	KY Srinivasan <kys@...rosoft.com>
To:	James Bottomley <James.Bottomley@...senPartnership.com>
CC:	Christoph Hellwig <hch@...radead.org>,
	"gregkh@...uxfoundation.org" <gregkh@...uxfoundation.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"devel@...uxdriverproject.org" <devel@...uxdriverproject.org>,
	"virtualization@...ts.osdl.org" <virtualization@...ts.osdl.org>,
	"ohering@...e.com" <ohering@...e.com>,
	"linux-scsi@...r.kernel.org" <linux-scsi@...r.kernel.org>,
	Haiyang Zhang <haiyangz@...rosoft.com>
Subject: RE: [PATCH 1/1] Drivers: scsi: storvsc: Don't pass ATA_16 command
 to the host



> -----Original Message-----
> From: James Bottomley [mailto:James.Bottomley@...senPartnership.com]
> Sent: Sunday, March 04, 2012 9:49 AM
> To: KY Srinivasan
> Cc: Christoph Hellwig; gregkh@...uxfoundation.org; linux-
> kernel@...r.kernel.org; devel@...uxdriverproject.org;
> virtualization@...ts.osdl.org; ohering@...e.com; linux-scsi@...r.kernel.org;
> Haiyang Zhang
> Subject: RE: [PATCH 1/1] Drivers: scsi: storvsc: Don't pass ATA_16 command to
> the host
> 
> On Sun, 2012-03-04 at 14:23 +0000, KY Srinivasan wrote:
> >
> > > -----Original Message-----
> > > From: Christoph Hellwig [mailto:hch@...radead.org]
> > > Sent: Sunday, March 04, 2012 4:12 AM
> > > To: KY Srinivasan
> > > Cc: gregkh@...uxfoundation.org; linux-kernel@...r.kernel.org;
> > > devel@...uxdriverproject.org; virtualization@...ts.osdl.org;
> ohering@...e.com;
> > > jbottomley@...allels.com; hch@...radead.org; linux-scsi@...r.kernel.org;
> > > Haiyang Zhang
> > > Subject: Re: [PATCH 1/1] Drivers: scsi: storvsc: Don't pass ATA_16 command to
> > > the host
> > >
> > > On Fri, Mar 02, 2012 at 12:49:07PM -0800, K. Y. Srinivasan wrote:
> > > > Windows hosts don't handle the ATA_16 command; don't pass it to the
> host.
> > >
> > > Most devices don't handle it, and answer with and unsupported opcode
> > > sense reason.  If hyperv iis buggy enough to crap out on it please add
> > > a comment explaining that.
> >
> > The host does not "crap out", it does return an error code but it is not
> "unsupported opcode".
> > The sense reason that comes back is a generic error SRB_STATUS code. It is
> easier for me to filter the
> > command on the outgoing side as opposed to dealing with a generic error code
> that is coming back from
> > the host.
> 
> That's the wrong thing to do ... you need to unwrap the error code.

I will see if this is even possible based on the current error codes I get back.

> The reason being I presume it's not impossible for Windows to host a
> device supporting ATA_16 and there are signs that this is going to be
> necessary to prevent data corruption on some USB devices ... if you just
> filter the command without checking if the host supports it, you're
> going to end up perpetuating the corruption problem.

We are talking of virtual  block devices exposed to Linux guests running on a Windows
hosts. I don't think they will ever need to support ATA_16 command on these virtual block
devices. I will however confirm with the Windows team.


Regards,

K. Y