drm/virtio: Annotate struct virtio_gpu_object_array with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct virtio_gpu_object_array.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: David Airlie <[email protected]>
Cc: Gerd Hoffmann <[email protected]>
Cc: Gurchetan Singh <[email protected]>
Cc: Chia-I Wu <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: [email protected]
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>
Reviewed-by: Gustavo A. R. Silva <[email protected]>
Signed-off-by: Christian König <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/gpu/drm/virtio/virtgpu_drv.h b/drivers/gpu/drm/virtio/virtgpu_drv.h
index 8513b671f871..96365a772f77 100644
--- a/drivers/gpu/drm/virtio/virtgpu_drv.h
+++ b/drivers/gpu/drm/virtio/virtgpu_drv.h
@@ -119,7 +119,7 @@ struct virtio_gpu_object_array {
 	struct ww_acquire_ctx ticket;
 	struct list_head next;
 	u32 nents, total;
-	struct drm_gem_object *objs[];
+	struct drm_gem_object *objs[] __counted_by(total);
 };
 
 struct virtio_gpu_vbuffer;