drm/vmwgfx: return -EFAULT for copy_to_user errors

copy_to/from_user() returns the number of bytes remaining to be copied
but we want to return a negative error code here.  This gets returned to
userspace.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

2 files changed, 7 insertions, 2 deletions

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
index bdd67cf83315..8e396850513c 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
@@ -644,6 +644,7 @@ int vmw_execbuf_ioctl(struct drm_device *dev, void *data,
         ret = copy_from_user(cmd, user_cmd, arg->command_size);
 
         if (unlikely(ret != 0)) {
+                ret = -EFAULT;
                 DRM_ERROR("Failed copying commands.\n");
                 goto out_commit;
         }
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
index f8fbbc67a406..8612378b131e 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
@@ -597,8 +597,10 @@ int vmw_surface_define_ioctl(struct drm_device *dev, void *data,
 
         ret = copy_from_user(srf->sizes, user_sizes,
                              srf->num_sizes * sizeof(*srf->sizes));
-        if (unlikely(ret != 0))
+        if (unlikely(ret != 0)) {
+                ret = -EFAULT;
                 goto out_err1;
+        }
 
         if (srf->scanout &&
             srf->num_sizes == 1 &&
@@ -697,9 +699,11 @@ int vmw_surface_reference_ioctl(struct drm_device *dev, void *data,
         if (user_sizes)
                 ret = copy_to_user(user_sizes, srf->sizes,
                                    srf->num_sizes * sizeof(*srf->sizes));
-        if (unlikely(ret != 0))
+        if (unlikely(ret != 0)) {
                 DRM_ERROR("copy_to_user failed %p %u\n",
                           user_sizes, srf->num_sizes);
+                ret = -EFAULT;
+        }
 out_bad_resource:
 out_no_reference:
         ttm_base_object_unref(&base);