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=-17.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_SANE_1 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 DF2ADC433E0 for ; Thu, 11 Feb 2021 12:04:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A983D64E95 for ; Thu, 11 Feb 2021 12:04:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230281AbhBKMEl (ORCPT ); Thu, 11 Feb 2021 07:04:41 -0500 Received: from userp2130.oracle.com ([156.151.31.86]:42250 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230328AbhBKMCV (ORCPT ); Thu, 11 Feb 2021 07:02:21 -0500 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 11BBmu7I193682; Thu, 11 Feb 2021 12:01:15 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=JlHMtwzoGJad+lRl/QAFsxOviAa1mqmYy7Gmfhb0yxA=; b=yLKjGowP88OgerhM4QsQJ+nql7HBpLv3Qt6SQOJHvqzEYiDTdnfaGA1S/GgAJm8qtKlZ BaTvzdUqf2UYVFjzopxB+4dQmmNhOkPnUYgwg2+EOTWbR3NXkpiR3a+iRfk4nswELsoD phirJNPMNuTgdsJEqMczW9vDDE0//q1/Sc6Hs15cEWE5IUdwT19ZuhtnE1ZjdTBkVuaf rJyzwMvow6OJmTkVYyKR28wzlzkexGHd1LUfQu/gSANThi4F0C6QA+/QjdoZdWtP/ZcB l95IuEuzzLFmKEd/3Sae552n5VP5Uy6M+dHo8U6/mAlyK7zyq5fFECuXvpP6nOEhqJQS og== Received: from userp3020.oracle.com (userp3020.oracle.com [156.151.31.79]) by userp2130.oracle.com with ESMTP id 36mv9dsc6v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 11 Feb 2021 12:01:15 +0000 Received: from pps.filterd (userp3020.oracle.com [127.0.0.1]) by userp3020.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 11BBolL2143114; Thu, 11 Feb 2021 12:01:12 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userp3020.oracle.com with ESMTP id 36j4vu5h33-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 11 Feb 2021 12:01:12 +0000 Received: from abhmp0008.oracle.com (abhmp0008.oracle.com [141.146.116.14]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 11BC16ou027776; Thu, 11 Feb 2021 12:01:06 GMT Received: from kadam (/102.36.221.92) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 11 Feb 2021 04:01:05 -0800 Date: Thu, 11 Feb 2021 15:00:51 +0300 From: Dan Carpenter To: Drew Fustini Cc: Linus Walleij , linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Tony Lindgren , Andy Shevchenko , Alexandre Belloni , Geert Uytterhoeven , Pantelis Antoniou , Jason Kridner , Robert Nelson , Joe Perches Subject: Re: [PATCH v4 2/2] pinctrl: pinmux: Add pinmux-select debugfs file Message-ID: <20210211120051.GN20820@kadam> References: <20210210222851.232374-1-drew@beagleboard.org> <20210210222851.232374-3-drew@beagleboard.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210210222851.232374-3-drew@beagleboard.org> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-IMR: 1 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=9891 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 adultscore=0 mlxlogscore=999 mlxscore=0 suspectscore=0 malwarescore=0 phishscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2102110108 X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=9891 signatures=668683 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 mlxlogscore=999 bulkscore=0 suspectscore=0 phishscore=0 adultscore=0 impostorscore=0 mlxscore=0 clxscore=1015 lowpriorityscore=0 malwarescore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2009150000 definitions=main-2102110108 Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Wed, Feb 10, 2021 at 02:28:54PM -0800, Drew Fustini wrote: > Add "pinmux-select" to debugfs which will activate a function and group > when "" are written to the file. The write > operation pinmux_select() handles this by checking that the names map to > valid selectors and then calling ops->set_mux(). > > The existing "pinmux-functions" debugfs file lists the pin functions > registered for the pin controller. For example: > > function: pinmux-uart0, groups = [ pinmux-uart0-pins ] > function: pinmux-mmc0, groups = [ pinmux-mmc0-pins ] > function: pinmux-mmc1, groups = [ pinmux-mmc1-pins ] > function: pinmux-i2c0, groups = [ pinmux-i2c0-pins ] > function: pinmux-i2c1, groups = [ pinmux-i2c1-pins ] > function: pinmux-spi1, groups = [ pinmux-spi1-pins ] > > To activate function pinmux-i2c1 and group pinmux-i2c1-pins: > > echo "pinmux-i2c1 pinmux-i2c1-pins" > pinmux-select > > Signed-off-by: Drew Fustini > --- > drivers/pinctrl/pinmux.c | 107 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 107 insertions(+) > > diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c > index c651b2db0925..23fa32f0a067 100644 > --- a/drivers/pinctrl/pinmux.c > +++ b/drivers/pinctrl/pinmux.c > @@ -673,6 +673,111 @@ void pinmux_show_setting(struct seq_file *s, > DEFINE_SHOW_ATTRIBUTE(pinmux_functions); > DEFINE_SHOW_ATTRIBUTE(pinmux_pins); > > +#define PINMUX_MAX_NAME 64 > +static ssize_t pinmux_select(struct file *file, const char __user *user_buf, > + size_t len, loff_t *ppos) > +{ > + struct seq_file *sfile = file->private_data; > + struct pinctrl_dev *pctldev = sfile->private; > + const struct pinmux_ops *pmxops = pctldev->desc->pmxops; > + const char *const *groups; > + char *buf, *fname, *gname; > + unsigned int num_groups; > + int fsel, gsel, ret; > + > + if (len > (PINMUX_MAX_NAME * 2)) { > + dev_err(pctldev->dev, "write too big for buffer"); > + return -EINVAL; > + } > + > + buf = kzalloc(PINMUX_MAX_NAME * 2, GFP_KERNEL); > + if (!buf) > + return -ENOMEM; > + > + fname = kzalloc(PINMUX_MAX_NAME, GFP_KERNEL); > + if (!fname) { > + ret = -ENOMEM; > + goto free_buf; > + } > + > + gname = kzalloc(PINMUX_MAX_NAME, GFP_KERNEL); > + if (!buf) { > + ret = -ENOMEM; > + goto free_fname; > + } > + > + ret = strncpy_from_user(buf, user_buf, PINMUX_MAX_NAME * 2); > + if (ret < 0) { > + dev_err(pctldev->dev, "failed to copy buffer from userspace"); > + goto free_gname; > + } > + buf[len-1] = '\0'; > + > + ret = sscanf(buf, "%s %s", fname, gname); > + if (ret != 2) { > + dev_err(pctldev->dev, "expected format: "); > + goto free_gname; > + } > + > + fsel = pinmux_func_name_to_selector(pctldev, fname); > + if (fsel < 0) { > + dev_err(pctldev->dev, "invalid function %s in map table\n", fname); > + ret = -EINVAL; > + goto free_gname; > + } > + > + ret = pmxops->get_function_groups(pctldev, fsel, &groups, &num_groups); > + if (ret) { > + dev_err(pctldev->dev, "no groups for function %d (%s)", fsel, fname); > + goto free_gname; > + > + } > + > + ret = match_string(groups, num_groups, gname); > + if (ret < 0) { > + dev_err(pctldev->dev, "invalid group %s", gname); > + goto free_gname; > + } > + > + ret = pinctrl_get_group_selector(pctldev, gname); > + if (ret < 0) { > + dev_err(pctldev->dev, "failed to get group selectorL %s", gname); > + goto free_gname; > + } > + gsel = ret; > + > + ret = pmxops->set_mux(pctldev, fsel, gsel); > + if (ret) { > + dev_err(pctldev->dev, "set_mux() failed: %d", ret); > + goto free_gname; > + } > + > + return len; > + > +free_gname: > + devm_kfree(pctldev->dev, gname); > +free_fname: > + devm_kfree(pctldev->dev, fname); > +free_buf: > + devm_kfree(pctldev->dev, buf); Ugh... I honestly thought Smatch was supposed to print a warning when you used devm_kfree() on kzalloc()ed memory, but I guess the warning is only the other way around. Smatch does complain about it as a leak because it was expecting a regular free. drivers/pinctrl/pinmux.c:330 pinmux_func_name_to_selector() warn: potential NULL parameter dereference 'fname' drivers/pinctrl/pinmux.c:764 pinmux_select() warn: possible memory leak of 'gname' drivers/pinctrl/pinmux.c:764 pinmux_select() warn: sscanf doesn't return error codes drivers/pinctrl/pinmux.c:764 pinmux_select() warn: returning success when sscanf failed And what about the success path? Shouldn't we free these on the success path as well? regards, dan carpenter