From: David Riley <davidriley@xxxxxxxxxxxx> virtio_gpu_get_caps_ioctl could return success with invalid data if a second caller to the function occurred after the entry was created in virtio_gpu_cmd_get_capset but prior to the virtio_gpu_cmd_capset_cb callback being called. This could leak contents of memory as well since the caps_cache allocation is done without zeroing. Signed-off-by: David Riley <davidriley@xxxxxxxxxxxx> --- drivers/gpu/drm/virtio/virtgpu_ioctl.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c index 949a264985fc..88c1ed57a3c5 100644 --- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c +++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c @@ -526,7 +526,6 @@ static int virtio_gpu_get_caps_ioctl(struct drm_device *dev, list_for_each_entry(cache_ent, &vgdev->cap_cache, head) { if (cache_ent->id == args->cap_set_id && cache_ent->version == args->cap_set_ver) { - ptr = cache_ent->caps_cache; spin_unlock(&vgdev->display_info_lock); goto copy_exit; } @@ -537,6 +536,7 @@ static int virtio_gpu_get_caps_ioctl(struct drm_device *dev, virtio_gpu_cmd_get_capset(vgdev, found_valid, args->cap_set_ver, &cache_ent); +copy_exit: ret = wait_event_timeout(vgdev->resp_wq, atomic_read(&cache_ent->is_valid), 5 * HZ); if (!ret) @@ -544,7 +544,6 @@ static int virtio_gpu_get_caps_ioctl(struct drm_device *dev, ptr = cache_ent->caps_cache; -copy_exit: if (copy_to_user((void __user *)(unsigned long)args->addr, ptr, size)) return -EFAULT; -- 2.22.0.rc1.311.g5d7573a151-goog _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel