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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 CDB9FC7618B for ; Thu, 25 Jul 2019 14:19:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A08ED22C7B for ; Thu, 25 Jul 2019 14:19:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564064372; bh=+SREVNLN8YNTldBQ2PvPDCC97GjzPF5jeHRJups4VgM=; h=Subject:To:Cc:References:From:Date:In-Reply-To:List-ID:From; b=WtmczKOfTLVy0K6uxaQecYwqOPXzxtbYo9FwAQ6o+0Lx56TKSUvvIt8pU80SfQWGJ Y8VUAYQNsq+TwO45slAHb8UaRG+85i9y+/nuqysyMqkNOuIUHCXNwiB4JWHukebLyT +tERiO0+ZgWIyma/qqlzoRBarci4yOvx1tkcLKn4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726470AbfGYOTc (ORCPT ); Thu, 25 Jul 2019 10:19:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:33090 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725944AbfGYOTc (ORCPT ); Thu, 25 Jul 2019 10:19:32 -0400 Received: from [192.168.1.112] (c-24-9-64-241.hsd1.co.comcast.net [24.9.64.241]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B5F2322C7B; Thu, 25 Jul 2019 14:19:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1564064371; bh=+SREVNLN8YNTldBQ2PvPDCC97GjzPF5jeHRJups4VgM=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=MgRnie9DoL9TlCbDgJ30z+SwK+qgW+2XLl+OOr3KVVUSV0yVlZtUx1wnUFHkjxY5B pHRCG+hRw9mC+J4mKDFq1xmGqguwMiwUa4QETXowHzoeqOS1jewPFEa1H3haLlzhUU dcS028+3QrnRGPmy6iStaNpDTRqC1rw2CoTsZ6pc= Subject: Re: [PATCH v2] usbip: tools: fix GCC8 warning for strncpy To: "Liu, Changcheng" , valentina.manea.m@gmail.com Cc: linux-usb@vger.kernel.org, shuah References: <20190725132209.GA27590@jerryopenix> From: shuah Message-ID: <2cac538b-3806-8b1f-9dce-34be9d862102@kernel.org> Date: Thu, 25 Jul 2019 08:19:19 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190725132209.GA27590@jerryopenix> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On 7/25/19 7:22 AM, Liu, Changcheng wrote: > GCC8 started emitting warning about using strncpy with number of bytes > exactly equal destination size which could lead to non-zero terminated > string being copied. Use "SYSFS_PATH_MAX - 1" & "SYSFS_BUS_ID_SIZE - 1" > as number of bytes to ensure name is always zero-terminated. > > Signed-off-by: Changcheng Liu > --- > v1 -> v2: > * Correct array tail index > --- > tools/usb/usbip/libsrc/usbip_common.c | 6 ++++-- > tools/usb/usbip/libsrc/usbip_device_driver.c | 6 ++++-- > 2 files changed, 8 insertions(+), 4 deletions(-) > > diff --git a/tools/usb/usbip/libsrc/usbip_common.c b/tools/usb/usbip/libsrc/usbip_common.c > index bb424638d75b..b8d7d480595a 100644 > --- a/tools/usb/usbip/libsrc/usbip_common.c > +++ b/tools/usb/usbip/libsrc/usbip_common.c > @@ -226,8 +226,10 @@ int read_usb_device(struct udev_device *sdev, struct usbip_usb_device *udev) > path = udev_device_get_syspath(sdev); > name = udev_device_get_sysname(sdev); > > - strncpy(udev->path, path, SYSFS_PATH_MAX); > - strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE); > + strncpy(udev->path, path, SYSFS_PATH_MAX - 1); > + udev->path[SYSFS_PATH_MAX - 1] = '\0'; > + strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE - 1); > + udev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0'; strlcpy() would be better choice here. Any reason to not use that? > > sscanf(name, "%u-%u", &busnum, &devnum); > udev->busnum = busnum; > diff --git a/tools/usb/usbip/libsrc/usbip_device_driver.c b/tools/usb/usbip/libsrc/usbip_device_driver.c > index 5a3726eb44ab..051d7d3f443b 100644 > --- a/tools/usb/usbip/libsrc/usbip_device_driver.c > +++ b/tools/usb/usbip/libsrc/usbip_device_driver.c > @@ -91,7 +91,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev) > copy_descr_attr16(dev, &descr, idProduct); > copy_descr_attr16(dev, &descr, bcdDevice); > > - strncpy(dev->path, path, SYSFS_PATH_MAX); > + strncpy(dev->path, path, SYSFS_PATH_MAX - 1); > + dev->path[SYSFS_PATH_MAX - 1] = '\0'; > > dev->speed = USB_SPEED_UNKNOWN; > speed = udev_device_get_sysattr_value(sdev, "current_speed"); > @@ -110,7 +111,8 @@ int read_usb_vudc_device(struct udev_device *sdev, struct usbip_usb_device *dev) > dev->busnum = 0; > > name = udev_device_get_sysname(plat); > - strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE); > + strncpy(dev->busid, name, SYSFS_BUS_ID_SIZE - 1); > + dev->busid[SYSFS_BUS_ID_SIZE - 1] = '\0'; strlcpy() would be better choice here. Any reason to not use that? > return 0; > err: > fclose(fd); > thanks, -- Shuah