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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,USER_AGENT_SANE_1 autolearn=no 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 5BAA9C352BE for ; Fri, 17 Apr 2020 11:26:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 35FF2208E4 for ; Fri, 17 Apr 2020 11:26:50 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="NW9h3C7l" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730310AbgDQL0t (ORCPT ); Fri, 17 Apr 2020 07:26:49 -0400 Received: from aserp2120.oracle.com ([141.146.126.78]:42686 "EHLO aserp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730176AbgDQL0t (ORCPT ); Fri, 17 Apr 2020 07:26:49 -0400 Received: from pps.filterd (aserp2120.oracle.com [127.0.0.1]) by aserp2120.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 03HBOxtT112760; Fri, 17 Apr 2020 11:26:41 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : in-reply-to; s=corp-2020-01-29; bh=2O0V3yblK/29tvWyAvBHQUZ86B8G/e/jVaheTAg9ans=; b=NW9h3C7l12IBiw3dwnhbItGHVe+6NB4UKB4+7UPW5vT91Y60g/arwqpQ3lh5UGmbyeqO p2eEbhI74qD+NqeKdDkkoIuB4UbK3eTKI13UpccLSwMuyTrAMhUBS7Hx4NMmBC7d8RyF SfrBD6hBkk9WWK4QQwFFqUG6A2pfMA8yLMNHvvRmVwdhBNFzBOsx7xoEHxwsPp5th4rj cAubsGgVjpyVHc2KT17rEZ7a6DBA19GSf91Oi8L2FNNy991jl0+tN8AAKWA1J3V3UYW2 Zhw132HJLj0yiB5DwLmE4jRP41oym7DpKrTBxdb4TIMR42l4cgO6kQcHhT7TNBqSfQOO Wg== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by aserp2120.oracle.com with ESMTP id 30dn95xk6x-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Apr 2020 11:26:41 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 03HBLMwB040528; Fri, 17 Apr 2020 11:26:40 GMT Received: from userv0122.oracle.com (userv0122.oracle.com [156.151.31.75]) by aserp3030.oracle.com with ESMTP id 30dn91c893-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 17 Apr 2020 11:26:40 +0000 Received: from abhmp0012.oracle.com (abhmp0012.oracle.com [141.146.116.18]) by userv0122.oracle.com (8.14.4/8.14.4) with ESMTP id 03HBQb78005629; Fri, 17 Apr 2020 11:26:38 GMT Received: from kadam (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Fri, 17 Apr 2020 04:26:37 -0700 Date: Fri, 17 Apr 2020 14:26:24 +0300 From: Dan Carpenter To: Jason Gunthorpe Cc: Christophe JAILLET , selvin.xavier@broadcom.com, devesh.sharma@broadcom.com, dledford@redhat.com, leon@kernel.org, colin.king@canonical.com, roland@purestorage.com, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH] RDMA/ocrdma: Fix an off-by-one issue in 'ocrdma_add_stat' Message-ID: <20200417112624.GS1163@kadam> References: <20200328073040.24429-1-christophe.jaillet@wanadoo.fr> <20200414183441.GA28870@ziepe.ca> <20200416130847.GP1163@kadam> <20200416184754.GZ5100@ziepe.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200416184754.GZ5100@ziepe.ca> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9593 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 mlxlogscore=999 suspectscore=0 malwarescore=0 spamscore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004170091 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9593 signatures=668686 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 clxscore=1015 malwarescore=0 bulkscore=0 priorityscore=1501 lowpriorityscore=0 mlxscore=0 phishscore=0 spamscore=0 impostorscore=0 suspectscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2003020000 definitions=main-2004170091 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 16, 2020 at 03:47:54PM -0300, Jason Gunthorpe wrote: > On Thu, Apr 16, 2020 at 04:08:47PM +0300, Dan Carpenter wrote: > > On Tue, Apr 14, 2020 at 03:34:41PM -0300, Jason Gunthorpe wrote: > > > The memcpy is still kind of silly right? What about this: > > > > > > static int ocrdma_add_stat(char *start, char *pcur, char *name, u64 count) > > > { > > > size_t len = (start + OCRDMA_MAX_DBGFS_MEM) - pcur; > > > int cpy_len; > > > > > > cpy_len = snprintf(pcur, len, "%s: %llu\n", name, count); > > > if (cpy_len >= len || cpy_len < 0) { > > > > The kernel version of snprintf() doesn't and will never return > > negatives. It would cause a huge security headache if it started > > returning negatives. > > Begs the question why it returns an int then :) People should use "int" as their default type. "int i;". It means "This is a normal number. Nothing special about it. It's not too high. It's not defined by hardware requirements." Other types call attention to themselves, but int is the humble datatype. regards, dan carpenter