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

[Philippe Mathieu-Daudé]

On 1/16/19 11:03 AM, Yuval Shaia wrote:
> On Mon, Jan 14, 2019 at 04:11:22PM +0100, Philippe Mathieu-Daudé wrote:
>> 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
> 
> will fix
> 
>>
>>> 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?
> 
> Yes, just to cover the case where fini() was called even when init() fails.

OK. Can you add a line about this in the commit description please?

With the comment updated:
Reviewed-by: Philippe Mathieu-Daudé <address@hidden>

> 
>>
>>> +        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);
>>> +    }
>>>  }
>>>