Re: [Qemu-devel] [PATCH] hw/rdma: Verify that ptr is not NULL before freeing

[Philippe Mathieu-Daudé]

Hi Yuval,

On 1/14/19 3:10 PM, Yuval Shaia wrote:
> Make sure objects are not NULL before calling to non-nulll-safe

null

> destructors.
> 
> Signed-off-by: Yuval Shaia <address@hidden>
> ---
>  hw/rdma/rdma_backend.c | 6 ++++--
>  hw/rdma/rdma_rm.c      | 7 ++++++-
>  2 files changed, 10 insertions(+), 3 deletions(-)
> 
> diff --git a/hw/rdma/rdma_backend.c b/hw/rdma/rdma_backend.c
> index b49edaacaf..3ee5172c96 100644
> --- a/hw/rdma/rdma_backend.c
> +++ b/hw/rdma/rdma_backend.c
> @@ -1066,8 +1066,10 @@ static void mad_fini(RdmaBackendDev *backend_dev)
>      pr_dbg("Stopping MAD\n");
>      disable_rdmacm_mux_async(backend_dev);
>      qemu_chr_fe_disconnect(backend_dev->rdmacm_mux.chr_be);
> -    qlist_destroy_obj(QOBJECT(backend_dev->recv_mads_list.list));
> -    qemu_mutex_destroy(&backend_dev->recv_mads_list.lock);
> +    if (backend_dev->recv_mads_list.list) {

This is only reachable when the backend didn't success at initializing,
right?

> +        qlist_destroy_obj(QOBJECT(backend_dev->recv_mads_list.list));
> +        qemu_mutex_destroy(&backend_dev->recv_mads_list.lock);
> +    }
>  }
>  
>  int rdma_backend_get_gid_index(RdmaBackendDev *backend_dev,
> diff --git a/hw/rdma/rdma_rm.c b/hw/rdma/rdma_rm.c
> index f5b1295890..8bf241e91f 100644
> --- a/hw/rdma/rdma_rm.c
> +++ b/hw/rdma/rdma_rm.c
> @@ -41,6 +41,9 @@ static inline void res_tbl_init(const char *name, 
> RdmaRmResTbl *tbl,
>  
>  static inline void res_tbl_free(RdmaRmResTbl *tbl)
>  {
> +    if (!tbl->bitmap) {
> +        return;
> +    }
>      qemu_mutex_destroy(&tbl->lock);
>      g_free(tbl->tbl);
>      g_free(tbl->bitmap);
> @@ -655,5 +658,7 @@ void rdma_rm_fini(RdmaDeviceResources *dev_res, 
> RdmaBackendDev *backend_dev,
>      res_tbl_free(&dev_res->cq_tbl);
>      res_tbl_free(&dev_res->pd_tbl);
>  
> -    g_hash_table_destroy(dev_res->qp_hash);
> +    if (dev_res->qp_hash) {
> +        g_hash_table_destroy(dev_res->qp_hash);
> +    }
>  }
>