Re: [PATCH for-rc] RDMA/cma: Remove open coding for overflow in cma_connect_ib

[Haakon Bugge]

> On 23 Nov 2021, at 10:11, Leon Romanovsky <leon@xxxxxxxxxx> wrote:
> 
> On Mon, Nov 22, 2021 at 05:48:53PM +0100, Håkon Bugge wrote:
>> The existing test is a little hard to comprehend. Use
>> check_add_overflow() instead.
>> 
>> Fixes: 04ded1672402 ("RDMA/cma: Verify private data length")
>> Signed-off-by: Håkon Bugge <haakon.bugge@xxxxxxxxxx>
>> ---
>> drivers/infiniband/core/cma.c | 3 +--
>> 1 file changed, 1 insertion(+), 2 deletions(-)
>> 
>> diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
>> index 835ac54..0435768 100644
>> --- a/drivers/infiniband/core/cma.c
>> +++ b/drivers/infiniband/core/cma.c
>> @@ -4093,8 +4093,7 @@ static int cma_connect_ib(struct rdma_id_private *id_priv,
>> 
>> 	memset(&req, 0, sizeof req);
>> 	offset = cma_user_data_offset(id_priv);
>> -	req.private_data_len = offset + conn_param->private_data_len;
>> -	if (req.private_data_len < conn_param->private_data_len)
>> +	if (check_add_overflow(offset, conn_param->private_data_len, &req.private_data_len))
>> 		return -EINVAL;
> 
> The same check exists in cma_resolve_ib_udp too.

Thanks for pointing it out Leon. Will send a v2.


Thxs, Håkon

> 
> Thanks
> 
>> 
>> 	if (req.private_data_len) {
>> -- 
>> 1.8.3.1