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=-7.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FSL_HELO_FAKE,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,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 571B6C433E3 for ; Thu, 27 Aug 2020 17:52:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1A75B2087E for ; Thu, 27 Aug 2020 17:52:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598550757; bh=iOxLgmIGQYHrxMElFT3exVNdV/6tWHPjbcYrBonVTVM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=o7OFSaQ/knqw5BCEJp7EKaUasx80FwP1gNF9AhRdZa26cglGHMBHbGImBsPQ6aeja SoMH48c3T00mTqSAc5YuLluzvR2PwNuSr4ozPfz6j399yqMBOtKEseZLxP6uA63UIp aYpIWbOZlASuM8v70tefMUSSrwJcbn3xArzFTKG0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727783AbgH0Rwf (ORCPT ); Thu, 27 Aug 2020 13:52:35 -0400 Received: from mail.kernel.org ([198.145.29.99]:40300 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726977AbgH0Rwb (ORCPT ); Thu, 27 Aug 2020 13:52:31 -0400 Received: from gmail.com (unknown [104.132.1.76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 2DEE5207CD; Thu, 27 Aug 2020 17:52:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1598550751; bh=iOxLgmIGQYHrxMElFT3exVNdV/6tWHPjbcYrBonVTVM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cun4+ImZ+yvvc46aY/WjwXu3szA3hLizs32IMEtX3BJt56GbT65LdsxBhLNLAkLFU KnbyJDTc/U9ezZ42ZjSfd+DoZfKSr2zm/NwzjQ1LayblEKQMMP9XWsPmqhka6hKFsm m2B9VvCgk7N+tocFDJ6KqxB3ZUGXc9g+zNcuYvww= Date: Thu, 27 Aug 2020 10:52:15 -0700 From: Eric Biggers To: Himadri Pandya Cc: davem@davemloft.net, kuba@kernel.org, linux-usb@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, syzkaller-bugs@googlegroups.com, linux-kernel-mentees@lists.linuxfoundation.org, gregkh@linuxfoundation.org Subject: Re: [PATCH] net: usb: Fix uninit-was-stored issue in asix_read_phy_addr() Message-ID: <20200827175215.GA2582911@gmail.com> References: <20200827065355.15177-1-himadrispandya@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200827065355.15177-1-himadrispandya@gmail.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Thu, Aug 27, 2020 at 12:23:55PM +0530, Himadri Pandya wrote: > The buffer size is 2 Bytes and we expect to receive the same amount of > data. But sometimes we receive less data and run into uninit-was-stored > issue upon read. Hence modify the error check on the return value to match > with the buffer size as a prevention. > > Reported-and-tested by: syzbot+a7e220df5a81d1ab400e@syzkaller.appspotmail.com > Signed-off-by: Himadri Pandya > --- > drivers/net/usb/asix_common.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/net/usb/asix_common.c b/drivers/net/usb/asix_common.c > index e39f41efda3e..7bc6e8f856fe 100644 > --- a/drivers/net/usb/asix_common.c > +++ b/drivers/net/usb/asix_common.c > @@ -296,7 +296,7 @@ int asix_read_phy_addr(struct usbnet *dev, int internal) > > netdev_dbg(dev->net, "asix_get_phy_addr()\n"); > > - if (ret < 0) { > + if (ret < 2) { > netdev_err(dev->net, "Error reading PHYID register: %02x\n", ret); > goto out; > } If ret is 0 or 1 here, shouldn't asix_read_phy_addr() return an error code instead of 0 or 1? - Eric