This is a note to let you know that I've just added the patch titled virtio-gpu: fix a missing check to avoid NULL dereference to the 5.19-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: virtio-gpu-fix-a-missing-check-to-avoid-null-derefer.patch and it can be found in the queue-5.19 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ca572b6a3a94a4cfab5d7957d5a176555242d5a7 Author: Xiaomeng Tong <xiam0nd.tong@xxxxxxxxx> Date: Sun Mar 27 13:09:45 2022 +0800 virtio-gpu: fix a missing check to avoid NULL dereference [ Upstream commit bd63f11f4c3c46afec07d821f74736161ff6e526 ] '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@xxxxxxxxx> Reviewed-by: Chia-I Wu <olvaffe@xxxxxxxxx> Link: http://patchwork.freedesktop.org/patch/msgid/20220327050945.1614-1-xiam0nd.tong@xxxxxxxxx [ kraxel: minor codestyle fixup ] Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/virtio/virtgpu_ioctl.c b/drivers/gpu/drm/virtio/virtgpu_ioctl.c index f8d83358d2a0..9b2702116f93 100644 --- a/drivers/gpu/drm/virtio/virtgpu_ioctl.c +++ b/drivers/gpu/drm/virtio/virtgpu_ioctl.c @@ -580,8 +580,10 @@ 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, - &cache_ent); + 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: