[PATCH] app/testpmd: fix segment fault with invalid queue id

[huangdengdui]

On 2023/5/16 23:12, Stephen Hemminger wrote:
> On Tue, 16 May 2023 19:00:21 +0800
> Dengdui Huang <huangdengdui at huawei.com> wrote:
> 
>> When input queue id is invalid, it will lead to
>> Segmentation fault, like:
>>
>> dpdk-testpmd -a 0000:01:00.0 -- -i
>> testpmd> show port 0 txq/rxq 99 desc 0 status  
>> Segmentation fault
>>
>> dpdk-testpmd -a 0000:01:00.0 -- -i
>> testpmd> show port 0 rxq 99 desc used count  
>> Segmentation fault
>>
>> This patch fixes it.
>>
>> In addition, this patch add the check for the offset
>> of the descriptor in case of other anomalies.
>>
>> Fixes: fae9aa717d6c ("app/testpmd: support checking descriptor status")
>> Fixes: 3f9acb5c83bb ("ethdev: avoid non-dataplane checks in Rx queue count")
>> Cc: stable at dpdk.org
>>
>> Signed-off-by: Dengdui Huang <huangdengdui at huawei.com>
> 
> What is the backtrace and device driver?  The problem is that other users
> besides testpmd might hit same problem.
> 
> It would make sense to have a function to test for valid rx and tx queue id
> in rte_ethdev. Similar to existing rte_eth_dev_is_valid_port() rather than
> open coding it.  Maybe rte_eth_dev_is_valid_rxq(port_id, queue_id)?
> 
> here was talk that the existing rx queue descriptor status is racy, and
> unused by any real application; and therefore would be good candidate for
> future removal.
Hi, Stephen

OK.

Agreed. But these APIs are still in dpdk, so testpmd as user side should use them correctly.

Thanks,
Dengdui