From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH] RDMA/hns: Use 64-bit arithmetic instead of 32-bit Date: Thu, 18 Oct 2018 10:02:58 +0200 Message-ID: <20181018080258.GA1720@embeddedor.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org To: Lijun Ou , "Wei Hu(Xavier)" , Doug Ledford , Jason Gunthorpe Cc: linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" List-Id: linux-rdma@vger.kernel.org Cast *max_num_sg* to u64 in order to give the compiler complete information about the proper arithmetic to use. Notice that such variable is used in a context that expects an expression of type u64 (64 bits, unsigned) and the following expression is currently being evaluated using 32-bit arithmetic: length = max_num_sg * page_size; Addresses-Coverity-ID: 1474517 ("Unintentional integer overflow") Signed-off-by: Gustavo A. R. Silva --- drivers/infiniband/hw/hns/hns_roce_mr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/infiniband/hw/hns/hns_roce_mr.c b/drivers/infiniband/hw/hns/hns_roce_mr.c index 521ad2a..d479d5e 100644 --- a/drivers/infiniband/hw/hns/hns_roce_mr.c +++ b/drivers/infiniband/hw/hns/hns_roce_mr.c @@ -1219,7 +1219,7 @@ struct ib_mr *hns_roce_alloc_mr(struct ib_pd *pd, enum ib_mr_type mr_type, int ret; page_size = 1 << (hr_dev->caps.pbl_buf_pg_sz + PAGE_SHIFT); - length = max_num_sg * page_size; + length = (u64)max_num_sg * page_size; if (mr_type != IB_MR_TYPE_MEM_REG) return ERR_PTR(-EINVAL); -- 2.7.4