[PATCH 5.19 335/717] virtio-gpu: fix shift wrapping bug in virtio_gpu_fence_event_create()

Greg Kroah-Hartman
2022-10-22T08:05:35Z

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit 37a78445763a5921bb54e9bad01937d0dfa521c1 ]

The ->ring_idx_mask variable is a u64 so static checkers, Smatch in
this case, complain if the BIT() is not also a u64.

drivers/gpu/drm/virtio/virtgpu_ioctl.c:50 virtio_gpu_fence_event_create()
warn: should '(1 << ring_idx)' be a 64 bit type?

Fixes: cd7f5ca33585 ("drm/virtio: implement context init: add virtio_gpu_fence_event")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Chia-I Wu <olvaffe@gmail.com>
Link: http://patchwork.freedesktop.org/patch/msgid/YygN7jY0GdUSQSy0@kili
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/gpu/drm/virtio/virtgpu_ioctl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index 3b1701607aae..5d05093014ac 100644
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -47,7 +47,7 @@ static int virtio_gpu_fence_event_create(struct drm_device *dev,
struct virtio_gpu_fence_event *e = NULL;
int ret;

- if (!(vfpriv->ring_idx_mask & (1 << ring_idx)))
+ if (!(vfpriv->ring_idx_mask & BIT_ULL(ring_idx)))
return 0;

e = kzalloc(sizeof(*e), GFP_KERNEL);
--
2.35.1