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Date:   Mon, 1 Mar 2021 20:56:28 +0100
From:   Heiko Carstens <hca@linux.ibm.com>
To:     Eric Farman <farman@linux.ibm.com>
Cc:     Wang Qing <wangqing@vivo.com>, Cornelia Huck <cohuck@redhat.com>,
        Halil Pasic <pasic@linux.ibm.com>,
        Vineeth Vijayan <vneethv@linux.ibm.com>,
        Peter Oberparleiter <oberpar@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        linux-s390@vger.kernel.org, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] s390: cio: Return -EFAULT if copy_to_user() fails
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References: <1614600093-13992-1-git-send-email-wangqing@vivo.com>
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 <e7edc20c-49d7-9297-7d0e-01f8a55c9c37@linux.ibm.com>
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On Mon, Mar 01, 2021 at 01:07:26PM -0500, Eric Farman wrote:
> 
> 
> On 3/1/21 8:13 AM, Heiko Carstens wrote:
> > On Mon, Mar 01, 2021 at 08:01:33PM +0800, Wang Qing wrote:
> > > The copy_to_user() function returns the number of bytes remaining to be
> > > copied, but we want to return -EFAULT if the copy doesn't complete.
> > > 
> > > Signed-off-by: Wang Qing <wangqing@vivo.com>
> > > ---
> > >   drivers/s390/cio/vfio_ccw_ops.c | 4 ++--
> > >   1 file changed, 2 insertions(+), 2 deletions(-)
> > 
> > Applied, thanks!
> 
> There's a third copy_to_user() call in this same routine, that deserves the
> same treatment. I'll get that fixup applied.

Thanks a lot - I actually realized that there was a third one, but
blindly assumed that the other patch addressed that (for which the
original broken commit e06670c5fe3b ("s390: vfio-ap: implement
VFIO_DEVICE_GET_INFO ioctl") got an amazing number of eight tags ;))

I'll keep your patch as a seperate one, since it fixes a different
upstream patch.