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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 1C3BFC7618B for ; Wed, 24 Jul 2019 04:37:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EF2C2218D4 for ; Wed, 24 Jul 2019 04:37:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726296AbfGXEh4 (ORCPT ); Wed, 24 Jul 2019 00:37:56 -0400 Received: from smtprelay0211.hostedemail.com ([216.40.44.211]:39759 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725883AbfGXEhz (ORCPT ); Wed, 24 Jul 2019 00:37:55 -0400 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay03.hostedemail.com (Postfix) with ESMTP id 09734837F24C; Wed, 24 Jul 2019 04:37:54 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: girl57_aa862e6d3a45 X-Filterd-Recvd-Size: 3717 Received: from XPS-9350.home (cpe-23-242-196-136.socal.res.rr.com [23.242.196.136]) (Authenticated sender: joe@perches.com) by omf03.hostedemail.com (Postfix) with ESMTPA; Wed, 24 Jul 2019 04:37:53 +0000 (UTC) Message-ID: Subject: Re: [Fwd: [PATCH 1/2] string: Add stracpy and stracpy_pad mechanisms] From: Joe Perches To: Julia Lawall Cc: cocci , LKML Date: Tue, 23 Jul 2019 21:37:51 -0700 In-Reply-To: References: <7ab8957eaf9b0931a59eff6e2bd8c5169f2f6c41.1563841972.git.joe@perches.com> <66fcdbf607d7d0bea41edb39e5579d63b62b7d84.camel@perches.com> <0f3ba090dfc956f5651e6c7c430abdba94ddcb8b.camel@perches.com> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.30.5-0ubuntu0.18.10.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2019-07-23 at 23:27 -0500, Julia Lawall wrote: > > On Tue, 23 Jul 2019, Joe Perches wrote: > > > On Tue, 2019-07-23 at 22:54 -0500, Julia Lawall wrote: > > > A seantic patch and the resulting output for the case where the third > > > arugument is a constant is attached. Likewise the resulting output on a > > > recent linux-next. > > > > > > julia > > > > Nice. Thanks Julia > > > > A couple issues: > > > > There is a problem with conversions with assignments > > of strlcpy() so ideally the cocci script should make sure > > any return value was not used before conversion. > > > > This is not a provably good conversion: > > > > drivers/s390/char/sclp_ftp.c > > @@ -114,8 +114,7 @@ static int sclp_ftp_et7(const struct hmc > > sccb->evbuf.mdd.ftp.length = ftp->len; > > sccb->evbuf.mdd.ftp.bufaddr = virt_to_phys(ftp->buf); > > > > - len = strlcpy(sccb->evbuf.mdd.ftp.fident, ftp->fname, > > - HMCDRV_FTP_FIDENT_MAX); > > + len = stracpy(sccb->evbuf.mdd.ftp.fident, ftp->fname); > > Sorry, I don't understand the issue here. What specifically should I be > looking for? The return value of strlcpy differs from (strscpy or stracpy). strlcpy returns the length of the src string str[sa]cpy returns the length of the src string if it fits in dest or -E2BIG if src is truncated by the size of dest or -E2BIG if dest is 0 length Any use of the strlcpy return value should not be converted because the logic after an assignment or use of the return value can not be assured to have the same behavior. > > And: > > > > I would have expected the bit below to find and convert uses like > > drivers/hwmon/adc128d818.c: strlcpy(info->type, "adc128d818", I2C_NAME_SIZE); > > but it seems none of those were converted. > > OK, thanks. I will check on it. Thanks again. > julia > > > I don't know why. > > > > //------------------------------------------ > > @r1@ > > struct i1 *e1; > > expression e2; > > identifier f,i1,i2; > > position p; > > @@ > > \(strscpy\|strlcpy\)(e1->f, e2, i2)@p > > > > @@ > > identifier r1.i1,r1.i2; > > type T; > > @@ > > struct i1 { ... T i1[i2]; ... } > > > > @@ > > identifier f,i2; > > expression e1,e2; > > position r1.p; > > @@ > > ( > > -strscpy > > +stracpy > > -strlcpy > > +stracpy > > )(e1->f, e2 > > - , i2 > > )@p > > //------------------------------------------ > > > > to find > > > >