Colin King
2021-Sep-30 10:27 UTC
[PATCH][next] drm/virtio: fix another potential integer overflow on shift of a int
From: Colin Ian King <colin.king at canonical.com>
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 at canonical.com>
---
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 b3b0557d72cf..0007e423d885 100644
--- 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;
}
--
2.32.0