On Fri, 27 Jul 2018 17:29:07 +0200 Thomas Huth <thuth@xxxxxxxxxx> wrote: > On 07/26/2018 09:54 PM, Christian Borntraeger wrote: > > From: Tony Krowiak <akrowiak@xxxxxxxxxxxxx> > > > > Introduces ioctl access to the VFIO AP Matrix device driver > > by implementing the VFIO_DEVICE_GET_INFO ioctl. This ioctl > > provides the VFIO AP Matrix device driver information to the > > guest machine. > > > > Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx> > > Reviewed-by: Pierre Morel <pmorel@xxxxxxxxxxxxx> > > Acked-by: Halil Pasic <pasic@xxxxxxxxxxxxx> > > Tested-by: Michael Mueller <mimu@xxxxxxxxxxxxx> > > Tested-by: Farhan Ali <alifm@xxxxxxxxxxxxx> > > Tested-by: Pierre Morel <pmorel@xxxxxxxxxxxxx> > > Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> > > --- > > drivers/s390/crypto/vfio_ap_ops.c | 43 +++++++++++++++++++++++++++++++ > > 1 file changed, 43 insertions(+) > > > > diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c > > index d06067a23000..01c429cb51d5 100644 > > --- a/drivers/s390/crypto/vfio_ap_ops.c > > +++ b/drivers/s390/crypto/vfio_ap_ops.c > > @@ -867,6 +867,48 @@ static void vfio_ap_mdev_release(struct mdev_device *mdev) > > module_put(THIS_MODULE); > > } > > > > +static int vfio_ap_mdev_get_device_info(unsigned long arg) > > +{ > > + unsigned long minsz; > > + struct vfio_device_info info; > > + > > + minsz = offsetofend(struct vfio_device_info, num_irqs); > > + > > + if (copy_from_user(&info, (void __user *)arg, minsz)) > > + return -EFAULT; > > + > > + if (info.argsz < minsz) { > > + pr_warn("%s: Argument size %u less than min size %li\n", > > + VFIO_AP_MODULE_NAME, info.argsz, minsz); > > Do you really need this pr_warn here? The -EINVAL should give a clear > indication about the problem already. (and in the worst case, a > malicious userspace program could use it to flood the kernel log) Agreed, that pr_warn should be dropped. FWIW, the other vfio drivers don't do this, either. > > > + return -EINVAL; > > + } > > + > > + info.flags = VFIO_DEVICE_FLAGS_AP; > > + info.num_regions = 0; > > + info.num_irqs = 0; > > + > > + return copy_to_user((void __user *)arg, &info, minsz); > > +} -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html