On Sat, Mar 26, 2022 at 10:09 PM Xiaomeng Tong xiam0nd.tong@gmail.com wrote:

'cache_ent' could be set NULL inside virtio_gpu_cmd_get_capset() and it will lead to a NULL dereference by a lately use of it (i.e., ptr = cache_ent->caps_cache). Fix it with a NULL check.

Fixes: 62fb7a5e10962 ("virtio-gpu: add 3d/virgl support") Signed-off-by: Xiaomeng Tong xiam0nd.tong@gmail.com

Reviewed-by: Chia-I Wu olvaffe@gmail.com

---

drivers/gpu/drm/virtio/virtgpu_ioctl.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c index c708bab555c6..b0f1c4d8fd23 100644 --- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c +++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c @@ -579,8 +579,10 @@ static int virtio_gpu_get_caps_ioctl(struct drm_device *dev, spin_unlock(&vgdev->display_info_lock);

    /* not in cache - need to talk to hw */

•   virtio_gpu_cmd_get_capset(vgdev, found_valid, args->cap_set_ver,
  

•   ret = virtio_gpu_cmd_get_capset(vgdev, found_valid, args->cap_set_ver,
                              &cache_ent);
  

•   if (ret)
  

•           return ret;
    virtio_gpu_notify(vgdev);
  
  

copy_exit:

base-commit: f443e374ae131c168a065ea1748feac6b2e76613

2.17.1