From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E828C46475 for ; Thu, 25 Oct 2018 15:33:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C798120834 for ; Thu, 25 Oct 2018 15:33:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C798120834 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=chelsio.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727824AbeJZAGS (ORCPT ); Thu, 25 Oct 2018 20:06:18 -0400 Received: from opengridcomputing.com ([72.48.214.68]:41718 "EHLO smtp.opengridcomputing.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727450AbeJZAGS (ORCPT ); Thu, 25 Oct 2018 20:06:18 -0400 X-Greylist: delayed 371 seconds by postgrey-1.27 at vger.kernel.org; Thu, 25 Oct 2018 20:06:18 EDT Received: from [10.10.0.239] (cody.ogc.int [10.10.0.239]) by smtp.opengridcomputing.com (Postfix) with ESMTPSA id B32FA2264E; Thu, 25 Oct 2018 10:26:51 -0500 (CDT) Reply-To: swise@chelsio.com Subject: Re: [PATCH] RDMA/cxgb3: Fix unintended sign extension To: Colin King , Doug Ledford , Jason Gunthorpe , linux-rdma@vger.kernel.org Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org References: <20181025143131.4048-1-colin.king@canonical.com> From: Steve Wise Message-ID: <34f7f28b-5f76-f6d0-d896-9a5550a8e3df@chelsio.com> Date: Thu, 25 Oct 2018 10:26:57 -0500 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181025143131.4048-1-colin.king@canonical.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/25/2018 9:31 AM, Colin King wrote: > From: Colin Ian King > > In the expression "utx_len << 28", utx_len starts as u8, but is promoted > to a signed int, then sign-extended to u64. If utx_len is 0xf8 or greater > then the sign extension will set all the upper bits of utx_cmd which is > probably not what was intended. Cast to utx_len to u64 to avoid the sign > extension. > > Detected by CoverityScan, CID#138764 ("Unintended sign extension") > > Fixes: b038ced7b370 ("RDMA/cxgb3: Add driver for Chelsio T3 RNIC") > Signed-off-by: Colin Ian King > --- > drivers/infiniband/hw/cxgb3/cxio_hal.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/infiniband/hw/cxgb3/cxio_hal.c b/drivers/infiniband/hw/cxgb3/cxio_hal.c > index dcb4bba522ba..c5cb80ccc6d6 100644 > --- a/drivers/infiniband/hw/cxgb3/cxio_hal.c > +++ b/drivers/infiniband/hw/cxgb3/cxio_hal.c > @@ -647,7 +647,7 @@ static int cxio_hal_ctrl_qp_write_mem(struct cxio_rdev *rdev_p, u32 addr, > wqe += (sizeof(struct t3_bypass_wr) >> 3); > utx_cmd = (T3_UTX_MEM_WRITE << 28) | (addr + i * 3); > utx_cmd <<= 32; > - utx_cmd |= (utx_len << 28) | ((utx_len << 2) + 1); > + utx_cmd |= ((u64)utx_len << 28) | ((utx_len << 2) + 1); > *wqe = cpu_to_be64(utx_cmd); > wqe++; > copy_data = (u8 *) data + i * 96; > Acked-by: Steve Wise