These judgments were used to keep the compatibility with older versions of userspace that don't have the field named "cap_flags" in structure hns_roce_ib_create_cq_resp. But it will be wrong to compare outlen with the size of resp if another new field were added in resp. oulen should be compared with the end offset of cap_flags in resp. Fixes: 4f8f0d5e33dd ("RDMA/hns: Package the flow of creating cq") Signed-off-by: Weihang Li <liweihang@xxxxxxxxxx> --- Related discussions can be found at: https://patchwork.kernel.org/patch/11372851/ drivers/infiniband/hw/hns/hns_roce_cq.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/infiniband/hw/hns/hns_roce_cq.c b/drivers/infiniband/hw/hns/hns_roce_cq.c index 5ffe4c9..5bfb52f 100644 --- a/drivers/infiniband/hw/hns/hns_roce_cq.c +++ b/drivers/infiniband/hw/hns/hns_roce_cq.c @@ -257,8 +257,8 @@ static int create_user_cq(struct hns_roce_dev *hr_dev, return ret; } - if ((hr_dev->caps.flags & HNS_ROCE_CAP_FLAG_RECORD_DB) && - (udata->outlen >= sizeof(*resp))) { + if (hr_dev->caps.flags & HNS_ROCE_CAP_FLAG_RECORD_DB && + udata->outlen >= offsetofend(typeof(*resp), cap_flags)) { ret = hns_roce_db_map_user(context, udata, ucmd.db_addr, &hr_cq->db); if (ret) { @@ -321,8 +321,8 @@ static void destroy_user_cq(struct hns_roce_dev *hr_dev, struct hns_roce_ucontext *context = rdma_udata_to_drv_context( udata, struct hns_roce_ucontext, ibucontext); - if ((hr_dev->caps.flags & HNS_ROCE_CAP_FLAG_RECORD_DB) && - (udata->outlen >= sizeof(*resp))) + if (hr_dev->caps.flags & HNS_ROCE_CAP_FLAG_RECORD_DB && + udata->outlen >= offsetofend(typeof(*resp), cap_flags)) hns_roce_db_unmap_user(context, &hr_cq->db); hns_roce_mtt_cleanup(hr_dev, &hr_cq->mtt); -- 2.8.1