Re: [patch 1/3] vfio: signedness bug in vfio_config_do_rw()

Dan Carpenter
2012-06-28T08:05:00Z

On Thu, Jun 28, 2012 at 09:15:12AM +0200, walter harms wrote:
>
>
> Am 28.06.2012 08:44, schrieb Dan Carpenter:
> > The "count" variable is unsigned here so the test for errors doesn't
> > work.
> >
> > Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> >
> > diff --git a/drivers/vfio/pci/vfio_pci_config.c b/drivers/vfio/pci/vfio_pci_config.c
> > index a4f7321..10bc6a8 100644
> > --- a/drivers/vfio/pci/vfio_pci_config.c
> > +++ b/drivers/vfio/pci/vfio_pci_config.c
> > @@ -1487,7 +1487,7 @@ static ssize_t vfio_config_do_rw(struct vfio_pci_device *vdev, char __user *buf,
> > if (perm->readfn) {
> > count = perm->readfn(vdev, *ppos, count,
> > perm, offset, &val);
> > - if (count < 0)
> > + if ((ssize_t)count < 0)
> > return count;
> > }
> >
>
> hi,
> I can only find a few references to vfio_config_do_rw(). From the
> patchit seems to me this is a wrapper for perm->readfn since both
> return ssize_t so why i count unsigned in the first place ?

Yeah. You're right. That was stupid of me. I'll resend.

regards,
dan carpenter