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Date: Mon, 26 Feb 2024 22:05:06 -0500
From: Alan Stern <stern@rowland.harvard.edu>
To: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Oliver Neukum <oneukum@suse.com>,
  syzbot <syzbot+28748250ab47a8f04100@syzkaller.appspotmail.com>,
  bvanassche@acm.org, emilne@redhat.com, gregkh@linuxfoundation.org,
  linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org,
  syzkaller-bugs@googlegroups.com, tasos@tasossah.com,
  usb-storage@lists.one-eyed-alien.net
Subject: Re: [syzbot] [usb-storage?] divide error in isd200_ata_command
Message-ID: <11ec2091-71c2-4dfb-be36-0cc21be32109@rowland.harvard.edu>
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On Mon, Feb 26, 2024 at 09:46:39PM -0500, Martin K. Petersen wrote:
> 
> Alan,
> 
> >> in isd200_scsi_to_ata() because it must not be called before
> >> isd200_get_inquiry_data() has completed.
> >
> > It can't be; isd200_get_inquiry_data is called by
> > isd200_Initialization during probe before any SCSI commands are
> > transmitted.
> 
> How do we end up with bad inquiry data (or rather bad ATA ID data)?

The data doesn't come from an actual ISD200 device.  It's from a 
deliberately faulty (for the obvious reason) emulation in userspace, 
created by the syzbot test code.

Alan Stern