vfio/pci: return -EFAULT if copy_to_user fails

The copy_to_user() function returns the number of bytes that were not
copied but we want to return -EFAULT on error here.

Fixes: 188ad9d6cbbc ('vfio/pci: Include sparse mmap capability for MSI-X table regions')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
index 1ce1d364308c..98059df9cff6 100644
--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -664,12 +664,11 @@ static long vfio_pci_ioctl(void *device_data,
                                 info.cap_offset = 0;
                         } else {
                                 vfio_info_cap_shift(&caps, sizeof(info));
-                                ret = copy_to_user((void __user *)arg +
-                                                   sizeof(info), caps.buf,
-                                                   caps.size);
-                                if (ret) {
+                                if (copy_to_user((void __user *)arg +
+                                                  sizeof(info), caps.buf,
+                                                  caps.size)) {
                                         kfree(caps.buf);
-                                        return ret;
+                                        return -EFAULT;
                                 }
                                 info.cap_offset = sizeof(info);
                         }