Re: [PATCH 2/6] block/mirror: fix use after free of local_err

[John Snow]

On 3/24/20 11:36 AM, Vladimir Sementsov-Ogievskiy wrote:
> local_err is used again in mirror_exit_common() after
> bdrv_set_backing_hd(), so we must zero it. Otherwise try to set
> non-NULL local_err will crash.
> 
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com>
> ---
>  block/mirror.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/block/mirror.c b/block/mirror.c
> index 447051dbc6..6203e5946e 100644
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -678,6 +678,7 @@ static int mirror_exit_common(Job *job)
>              bdrv_set_backing_hd(target_bs, backing, &local_err);
>              if (local_err) {
>                  error_report_err(local_err);
> +                local_err = NULL;
>                  ret = -EPERM;
>              }
>          }
> 

Reviewed-by: John Snow <js...@redhat.com>