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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 F19F9C46460 for ; Sun, 12 Aug 2018 18:35:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B604E2199B for ; Sun, 12 Aug 2018 18:35:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B604E2199B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=perches.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 S1728053AbeHLVN5 (ORCPT ); Sun, 12 Aug 2018 17:13:57 -0400 Received: from smtprelay0119.hostedemail.com ([216.40.44.119]:46931 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727550AbeHLVN4 (ORCPT ); Sun, 12 Aug 2018 17:13:56 -0400 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay05.hostedemail.com (Postfix) with ESMTP id 986F518028E9F; Sun, 12 Aug 2018 18:35:02 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: size83_831fd4dc17922 X-Filterd-Recvd-Size: 4678 Received: from XPS-9350.home (unknown [47.151.153.53]) (Authenticated sender: joe@perches.com) by omf06.hostedemail.com (Postfix) with ESMTPA; Sun, 12 Aug 2018 18:35:00 +0000 (UTC) Message-ID: <10f9f13a5421299a6efda1e1f84ab304ef18ddec.camel@perches.com> Subject: Re: [PATCH] USB: core: devio: fixed a trailing statement code style issue From: Joe Perches To: Tom Todd , gregkh@linuxfoundation.org Cc: stern@rowland.harvard.edu, dan.carpenter@oracle.com, arvind.yadav.cs@gmail.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Date: Sun, 12 Aug 2018 11:34:59 -0700 In-Reply-To: <20180812180656.26079-1-thomas.m.a.todd@gmail.com> References: <20180812180656.26079-1-thomas.m.a.todd@gmail.com> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.28.1-2 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 Sun, 2018-08-12 at 19:06 +0100, Tom Todd wrote: > Fixed a code styling issue while it's OK to fix style only issues, it's much better to reorganize the code for reader clarity. For this code, something like: o use memdup_user o use an exit label to free allocated memory o invert tests to return on unexpected results o move logical continuations to EOL o don't use successive code like: if (foo) return -ERRNO; else if (bar) return -ERRNO; else baz; simpler and less indentation is: if (foo) return -ERRNO; if (bar) return -ERRNO; baz; --- drivers/usb/core/devio.c | 68 ++++++++++++++++++++++++++---------------------- 1 file changed, 37 insertions(+), 31 deletions(-) diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index 6ce77b33da61..74ae4e052357 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -2118,68 +2118,74 @@ static int proc_ioctl(struct usb_dev_state *ps, struct usbdevfs_ioctl *ctl) /* alloc buffer */ size = _IOC_SIZE(ctl->ioctl_code); if (size > 0) { - buf = kmalloc(size, GFP_KERNEL); - if (buf == NULL) - return -ENOMEM; - if ((_IOC_DIR(ctl->ioctl_code) & _IOC_WRITE)) { - if (copy_from_user(buf, ctl->data, size)) { - kfree(buf); + if (_IOC_DIR(ctl->ioctl_code) & _IOC_WRITE) { + buf = memdup_user(ctl->data, size); + if (!buf) return -EFAULT; - } } else { - memset(buf, 0, size); + buf = kzalloc(size, GFP_KERNEL); + if (!buf) + return -ENOMEM; } } if (!connected(ps)) { - kfree(buf); - return -ENODEV; + retval = -ENODEV; + goto exit; } - - if (ps->dev->state != USB_STATE_CONFIGURED) + if (ps->dev->state != USB_STATE_CONFIGURED) { retval = -EHOSTUNREACH; - else if (!(intf = usb_ifnum_to_if(ps->dev, ctl->ifno))) + goto exit; + } + intf = usb_ifnum_to_if(ps->dev, ctl->ifno); + if (!intf) { retval = -EINVAL; - else switch (ctl->ioctl_code) { + goto exit; + } + switch (ctl->ioctl_code) { /* disconnect kernel driver from interface */ case USBDEVFS_DISCONNECT: - if (intf->dev.driver) { - driver = to_usb_driver(intf->dev.driver); - dev_dbg(&intf->dev, "disconnect by usbfs\n"); - usb_driver_release_interface(driver, intf); - } else + if (!intf->dev.driver) { retval = -ENODATA; + goto exit; + } + driver = to_usb_driver(intf->dev.driver); + dev_dbg(&intf->dev, "disconnect by usbfs\n"); + usb_driver_release_interface(driver, intf); break; /* let kernel drivers try to (re)bind to the interface */ case USBDEVFS_CONNECT: - if (!intf->dev.driver) - retval = device_attach(&intf->dev); - else + if (!intf->dev.driver) { retval = -EBUSY; + goto exit; + } + retval = device_attach(&intf->dev); break; /* talk directly to the interface's driver */ default: if (intf->dev.driver) driver = to_usb_driver(intf->dev.driver); - if (driver == NULL || driver->unlocked_ioctl == NULL) { + if (!driver || !driver->unlocked_ioctl) { retval = -ENOTTY; - } else { - retval = driver->unlocked_ioctl(intf, ctl->ioctl_code, buf); - if (retval == -ENOIOCTLCMD) - retval = -ENOTTY; + goto exit; + } + retval = driver->unlocked_ioctl(intf, ctl->ioctl_code, buf); + if (retval == -ENOIOCTLCMD) { + retval = -ENOTTY; + goto exit; } + break; } /* cleanup and return */ - if (retval >= 0 - && (_IOC_DIR(ctl->ioctl_code) & _IOC_READ) != 0 - && size > 0 - && copy_to_user(ctl->data, buf, size) != 0) + if (retval >= 0 && (_IOC_DIR(ctl->ioctl_code) & _IOC_READ) != 0 && + size > 0 && copy_to_user(ctl->data, buf, size) != 0) retval = -EFAULT; +exit: kfree(buf); return retval; }