Re: [dpdk-dev] Unsafe array accesses in rte_sched.c

["Simon Kågström" <simon.kagstrom@netinsight.net>]

On 2015-10-16 15:39, Dumitrescu, Cristian wrote:
>>         port->qsize_add[12] = port->qsize_add[11] + port->qsize[2];
>>         port->qsize_add[13] = port->qsize_add[12] + port->qsize[3];
>>         port->qsize_add[14] = port->qsize_add[13] + port->qsize[3];
>>         port->qsize_add[15] = port->qsize_add[14] + port->qsize[3];
>>
>>         port->qsize_sum = port->qsize_add[15] + port->qsize[3];
>>   }
>>
>> but port->qsize is actually defined as
>>
>>   uint16_t qsize[RTE_SCHED_TRAFFIC_CLASSES_PER_PIPE];
>>
> 
> Not sure what you see "unsafe" here: qsize is an array of 4 elements, while qsize_add is a different array of 16 elements? Please explain.

Sorry, I should have been more explicit: What I mean that the code
should loop over RTE_SCHED_TRAFFIC_CLASSES_PER_PIPE instead of
hard-coding the numbers.

It certainly works with the current RTE_SCHED_TRAFFIC_CLASSES_PER_PIPE,
but it would be safer (and in my opinion more clear) if it would not
assume RTE_SCHED_TRAFFIC_CLASSES_PER_PIPE == 4.

// Simon