From: Roberto Sassu <roberto.sassu@xxxxxxxxxx> commit 6b79f96f4a23846516e5e6e4dd37fc06f43a60dd upstream. If virtio_gpu_object_shmem_init() fails (e.g. due to fault injection, as it happened in the bug report by syzbot), virtio_gpu_array_put_free() could be called with objs equal to NULL. Ensure that objs is not NULL in virtio_gpu_array_put_free(), or otherwise return from the function. Cc: stable@xxxxxxxxxxxxxxx # 5.13.x Signed-off-by: Roberto Sassu <roberto.sassu@xxxxxxxxxx> Reported-by: syzbot+e9072e90624a31dfa85f@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: 377f8331d0565 ("drm/virtio: fix possible leak/unlock virtio_gpu_object_array") Link: http://patchwork.freedesktop.org/patch/msgid/20211213183122.838119-1-roberto.sassu@xxxxxxxxxx Signed-off-by: Gerd Hoffmann <kraxel@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/virtio/virtgpu_gem.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/gpu/drm/virtio/virtgpu_gem.c +++ b/drivers/gpu/drm/virtio/virtgpu_gem.c @@ -248,6 +248,9 @@ void virtio_gpu_array_put_free(struct vi { u32 i; + if (!objs) + return; + for (i = 0; i < objs->nents; i++) drm_gem_object_put(objs->objs[i]); virtio_gpu_array_free(objs);