drm/virtio: fix another potential integer overflow on shift of a int

The left shift of unsigned int 32 bit integer constant 1 is evaluated
using 32 bit arithmetic and then assigned to a signed 64 bit integer.
In the case where value is 32 or more this can lead to an overflow
(value can be in range 0..MAX_CAPSET_ID (63). Fix this by shifting
the value 1ULL instead.

Addresses-Coverity: ("Uninitentional integer overflow")
Fixes: 4fb530e5caf7 ("drm/virtio: implement context init: support init ioctl")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210930102748.16922-1-colin.king@canonical.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
index b3b0557..0007e42 100644 (file)
--- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c
+++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c
@@ -774,7 +774,7 @@ static int virtio_gpu_context_init_ioctl(struct drm_device *dev,
                                goto out_unlock;
                        }
 
-                       if ((vgdev->capset_id_mask & (1 << value)) == 0) {
+                       if ((vgdev->capset_id_mask & (1ULL << value)) == 0) {
                                ret = -EINVAL;
                                goto out_unlock;
                        }