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=-3.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 49749C433E7 for ; Sun, 11 Oct 2020 18:33:10 +0000 (UTC) Received: from silver.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BFFC02145D for ; Sun, 11 Oct 2020 18:33:09 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BFFC02145D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=perches.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-kernel-mentees-bounces@lists.linuxfoundation.org Received: from localhost (localhost [127.0.0.1]) by silver.osuosl.org (Postfix) with ESMTP id 5E4C8204D8; Sun, 11 Oct 2020 18:33:09 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from silver.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id rrY5biXXqinl; Sun, 11 Oct 2020 18:33:07 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by silver.osuosl.org (Postfix) with ESMTP id 65EF4204C2; Sun, 11 Oct 2020 18:33:07 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 4B59CC0052; Sun, 11 Oct 2020 18:33:07 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id CA8AFC0051 for ; Sun, 11 Oct 2020 18:33:05 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id B26D185B99 for ; Sun, 11 Oct 2020 18:33:05 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id We9yfjlJYSxM for ; Sun, 11 Oct 2020 18:33:04 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from smtprelay.hostedemail.com (smtprelay0206.hostedemail.com [216.40.44.206]) by fraxinus.osuosl.org (Postfix) with ESMTPS id BA5AA85008 for ; Sun, 11 Oct 2020 18:33:04 +0000 (UTC) Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay06.hostedemail.com (Postfix) with ESMTP id 72AC518224D6B; Sun, 11 Oct 2020 18:33:03 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: smell48_4f01435271f4 X-Filterd-Recvd-Size: 4300 Received: from XPS-9350.home (unknown [47.151.133.149]) (Authenticated sender: joe@perches.com) by omf04.hostedemail.com (Postfix) with ESMTPA; Sun, 11 Oct 2020 18:33:01 +0000 (UTC) Message-ID: <6307397bd43636fea2e7341d24417cbbc3aaf922.camel@perches.com> From: Joe Perches To: Jakub Kicinski , Anant Thazhemadam Date: Sun, 11 Oct 2020 11:33:00 -0700 In-Reply-To: <20201011105934.5c988cd3@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> References: <20201010064459.6563-1-anant.thazhemadam@gmail.com> <20201011173030.141582-1-anant.thazhemadam@gmail.com> <20201011105934.5c988cd3@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> User-Agent: Evolution 3.36.4-0ubuntu1 MIME-Version: 1.0 Cc: sfr@canb.auug.org.au, petkan@nucleusys.com, netdev@vger.kernel.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-next@vger.kernel.org, linux-kernel-mentees@lists.linuxfoundation.org, davem@davemloft.net Subject: Re: [Linux-kernel-mentees] [PATCH v2] net: usb: rtl8150: don't incorrectly assign random MAC addresses X-BeenThere: linux-kernel-mentees@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-kernel-mentees-bounces@lists.linuxfoundation.org Sender: "Linux-kernel-mentees" On Sun, 2020-10-11 at 10:59 -0700, Jakub Kicinski wrote: > On Sun, 11 Oct 2020 23:00:30 +0530 Anant Thazhemadam wrote: > > In set_ethernet_addr(), if get_registers() succeeds, the ethernet address > > that was read must be copied over. Otherwise, a random ethernet address > > must be assigned. > > > > get_registers() returns 0 if successful, and negative error number > > otherwise. However, in set_ethernet_addr(), this return value is > > incorrectly checked. > > > > Since this return value will never be equal to sizeof(node_id), a > > random MAC address will always be generated and assigned to the > > device; even in cases when get_registers() is successful. > > > > Correctly modifying the condition that checks if get_registers() was > > successful or not fixes this problem, and copies the ethernet address > > appropriately. There are many unchecked uses of set_registers and get_registers in this file. If failures are really expected, then it might be better to fix them up too. $ git grep -w '[gs]et_registers' drivers/net/usb/rtl8150.c drivers/net/usb/rtl8150.c:static int get_registers(rtl8150_t * dev, u16 indx, u16 size, void *data) drivers/net/usb/rtl8150.c:static int set_registers(rtl8150_t * dev, u16 indx, u16 size, const void *data) drivers/net/usb/rtl8150.c: set_registers(dev, PHYADD, sizeof(data), data); drivers/net/usb/rtl8150.c: set_registers(dev, PHYCNT, 1, &tmp); drivers/net/usb/rtl8150.c: get_registers(dev, PHYCNT, 1, data); drivers/net/usb/rtl8150.c: get_registers(dev, PHYDAT, 2, data); drivers/net/usb/rtl8150.c: set_registers(dev, PHYADD, sizeof(data), data); drivers/net/usb/rtl8150.c: set_registers(dev, PHYCNT, 1, &tmp); drivers/net/usb/rtl8150.c: get_registers(dev, PHYCNT, 1, data); drivers/net/usb/rtl8150.c: ret = get_registers(dev, IDR, sizeof(node_id), node_id); drivers/net/usb/rtl8150.c: set_registers(dev, IDR, netdev->addr_len, netdev->dev_addr); drivers/net/usb/rtl8150.c: get_registers(dev, CR, 1, &cr); drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &cr); drivers/net/usb/rtl8150.c: set_registers(dev, IDR_EEPROM + (i * 2), 2, drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &cr); drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &data); drivers/net/usb/rtl8150.c: get_registers(dev, CR, 1, &data); drivers/net/usb/rtl8150.c: set_registers(dev, RCR, 1, &rcr); drivers/net/usb/rtl8150.c: set_registers(dev, TCR, 1, &tcr); drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &cr); drivers/net/usb/rtl8150.c: get_registers(dev, MSR, 1, &msr); drivers/net/usb/rtl8150.c: get_registers(dev, CR, 1, &cr); drivers/net/usb/rtl8150.c: set_registers(dev, CR, 1, &cr); drivers/net/usb/rtl8150.c: get_registers(dev, CSCR, 2, &tmp); drivers/net/usb/rtl8150.c: set_registers(dev, IDR, 6, netdev->dev_addr); drivers/net/usb/rtl8150.c: get_registers(dev, BMCR, 2, &bmcr); drivers/net/usb/rtl8150.c: get_registers(dev, ANLP, 2, &lpa); _______________________________________________ Linux-kernel-mentees mailing list Linux-kernel-mentees@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees