On Fri, 23 Oct 2020 14:34:50 +0300 Dan Carpenter <dan.carpenter@xxxxxxxxxx> wrote: > The copy_to_user() function returns the number of bytes remaining to be > copied, but this code should return -EFAULT. > > Fixes: df747bcd5b21 ("vfio/fsl-mc: Implement VFIO_DEVICE_GET_REGION_INFO ioctl call") > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > --- > drivers/vfio/fsl-mc/vfio_fsl_mc.c | 8 ++++++-- > 1 file changed, 6 insertions(+), 2 deletions(-) Applied this and the following patch to vfio for-linus branch with Diana's acks for v5.10. Thanks, Alex > diff --git a/drivers/vfio/fsl-mc/vfio_fsl_mc.c b/drivers/vfio/fsl-mc/vfio_fsl_mc.c > index 0113a980f974..21f22e3da11f 100644 > --- a/drivers/vfio/fsl-mc/vfio_fsl_mc.c > +++ b/drivers/vfio/fsl-mc/vfio_fsl_mc.c > @@ -248,7 +248,9 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd, > info.size = vdev->regions[info.index].size; > info.flags = vdev->regions[info.index].flags; > > - return copy_to_user((void __user *)arg, &info, minsz); > + if (copy_to_user((void __user *)arg, &info, minsz)) > + return -EFAULT; > + return 0; > } > case VFIO_DEVICE_GET_IRQ_INFO: > { > @@ -267,7 +269,9 @@ static long vfio_fsl_mc_ioctl(void *device_data, unsigned int cmd, > info.flags = VFIO_IRQ_INFO_EVENTFD; > info.count = 1; > > - return copy_to_user((void __user *)arg, &info, minsz); > + if (copy_to_user((void __user *)arg, &info, minsz)) > + return -EFAULT; > + return 0; > } > case VFIO_DEVICE_SET_IRQS: > {