Re: [dpdk-dev] [RFC 1/2] mbuf: add a sanity check on segment metadata

[David Marchand <david.marchand@6wind.com>]

On Thu, Aug 23, 2018 at 9:39 AM, Olivier Matz <olivier.matz@6wind.com> wrote:
> On Mon, Aug 13, 2018 at 06:03:45PM +0200, David Marchand wrote:
>> Add some basic check on the segments offset and length metadata:
>> always funny to have a < 0 tailroom cast to uint16_t ;-).
>>
>> Signed-off-by: David Marchand <david.marchand@6wind.com>
>> ---
>>  lib/librte_mbuf/rte_mbuf.c | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/lib/librte_mbuf/rte_mbuf.c b/lib/librte_mbuf/rte_mbuf.c
>> index e714c5a..7eeef12 100644
>> --- a/lib/librte_mbuf/rte_mbuf.c
>> +++ b/lib/librte_mbuf/rte_mbuf.c
>> @@ -200,6 +200,8 @@ rte_mbuf_sanity_check(const struct rte_mbuf *m, int is_header)
>>       pkt_len = m->pkt_len;
>>
>>       do {
>> +             if (m->data_off + m->data_len > m->buf_len)
>> +                     rte_panic("bad segment metadata\n");
>
> What about spliting the test into two? This would help to clarify
> the error messages. I also suggest add casts to uint32 to ensure
> that there is no overflow.

Sure, will do.

-- 
David Marchand