Re: [PATCH v2 for-rc] RDMA/srpt: Fix UAF when srpt_add_one() failed

[Junxian Huang <huangjunxian6@hisilicon.com>]

On 2024/8/2 0:20, Bart Van Assche wrote:
> On 8/1/24 5:32 AM, Junxian Huang wrote:
>> Besides, exchange the order of INIT_WORK() and srpt_refresh_port()
>> in srpt_add_one(), so that when srpt_refresh_port() failed, there
>> is no need to cancel the work in this iteration.
> 
> The above description is wrong. There is no need to cancel work after
> INIT_WORK() has been called if the work has never been queued. Hence,
> moving the INIT_WORK() call is not necessary.
> 

Well, inspired by your comment I looked into the code again and I think
perhaps this whole patch is not necessary.

I encountered this problem in 5.10 kernel, where ib_register_event_handler()
was called before the for-loop. But this bug has been fixed in the current
mainline, and the work won't be queued until the whole for-loop is finished.

Thanks,
Junxian

>> @@ -3220,7 +3221,6 @@ static int srpt_add_one(struct ib_device *device)
>>           sport->port_attrib.srp_max_rsp_size = DEFAULT_MAX_RSP_SIZE;
>>           sport->port_attrib.srp_sq_size = DEF_SRPT_SQ_SIZE;
>>           sport->port_attrib.use_srq = false;
>> -        INIT_WORK(&sport->work, srpt_refresh_port_work);
>>             ret = srpt_refresh_port(sport);
>>           if (ret) {
>> @@ -3229,6 +3229,8 @@ static int srpt_add_one(struct ib_device *device)
>>               i--;
>>               goto err_port;
>>           }
>> +
>> +        INIT_WORK(&sport->work, srpt_refresh_port_work);
>>       }
> 
> I don't think that this change is necessary.
> 
> Bart.
>