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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,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 6A029C433E0 for ; Fri, 19 Feb 2021 03:18:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 396FE64ED7 for ; Fri, 19 Feb 2021 03:18:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229649AbhBSDSa (ORCPT ); Thu, 18 Feb 2021 22:18:30 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41124 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229553AbhBSDS3 (ORCPT ); Thu, 18 Feb 2021 22:18:29 -0500 Received: from mail-pl1-x633.google.com (mail-pl1-x633.google.com [IPv6:2607:f8b0:4864:20::633]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3D046C061574; Thu, 18 Feb 2021 19:17:49 -0800 (PST) Received: by mail-pl1-x633.google.com with SMTP id b8so2561106plh.12; Thu, 18 Feb 2021 19:17:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=OwNV1ruvrzmTZHtKgrE8lgFC0d23DBddIr+rAQj3fCA=; b=mQVOnq7krNIwtuspcWotiXg5heQPESU1irjCJKrU1ZtWJvLEO6jBJeWwIUIORpQ6tH 7D+TeDxnfet25IIiZr0F1aAgjoZTMHeK8qsviNcF3zyBdjodrClDssx8AI8ixMKZZo42 otffnoTunn14v3Zh5pxhuOdzB5eoAhXL1TBcLTqJkoGPkpJdcgjGVQsRLu6MgBpFNbAA n5mk4y26kht2t/OmXeehMcFdBp1fnxflbwsv/3slI2X2Kz9xDcO4aozgwA18RSix9s5D j58yYanvC8U/qwaMdIspKo8NmBZxm2JbidJVcn64Oyw5cVIYotXgRp7tbcYIWd73ugm0 RYlw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=OwNV1ruvrzmTZHtKgrE8lgFC0d23DBddIr+rAQj3fCA=; b=bFIiKP2DiPIxyJqGvcbVqjr0RKvsI9D23vVOBbqffx4v7iBCbYQQV6yAkRUX1EMVru tQq0b73IipZ1NaAXRxPtcAmI/JWekN2Sr/APzv6jFpzygNN1/71BZk7r/7252TyfE21b KKKedqzjqvO/PlJpHNP+QMZfHUsKHgzeiPYlLHILvvipqYqqjWsrVglxuMIJguTfxdnt JzTiGzwLVNhPff1W1WRr9527534UnNCd3/QzfHVrkyPQ5q9O+syIcj+Fn02oOjEkHgIt fLxLfDBZTucwcopmh4CisEXZ22+CME0X21JdGS7NeVss2QDoO0yGKBOJ3CrD0gNkgiYN R37w== X-Gm-Message-State: AOAM53256Av7LCPvsFKtJvP/+Zwxt7GTEM8gdFeGGfmE7rzxALggoj0T UH/+WWM3fqndmHCQcqyRKUk= X-Google-Smtp-Source: ABdhPJxcaFa410Ckz6MrT2jZ1L/de+5zRk4l6zVCRdamgk6nWQVdwrJsbyrFtsvXY7xe/3XJYmvRRg== X-Received: by 2002:a17:90b:1093:: with SMTP id gj19mr6909241pjb.40.1613704668174; Thu, 18 Feb 2021 19:17:48 -0800 (PST) Received: from google.com ([2620:15c:202:201:8d20:87b2:91b7:7f7b]) by smtp.gmail.com with ESMTPSA id b15sm3521500pgg.85.2021.02.18.19.17.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 18 Feb 2021 19:17:47 -0800 (PST) Date: Thu, 18 Feb 2021 19:17:44 -0800 From: Dmitry Torokhov To: Dan Carpenter Cc: Stephen Kitt , linux-input@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: Re: [PATCH] Input: joydev - prevent potential read overflow in ioctl Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: kernel-janitors@vger.kernel.org Hi Dan, On Wed, Feb 17, 2021 at 09:10:15AM +0300, Dan Carpenter wrote: > The problem here is that "len" might be less than "joydev->nabs" so the > loops which verfy abspam[i] and keypam[] might read beyond the buffer. > > Fixes: 999b874f4aa3 ("Input: joydev - validate axis/button maps before clobbering current ones") > Signed-off-by: Dan Carpenter Thank you for the patch. > --- > drivers/input/joydev.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/input/joydev.c b/drivers/input/joydev.c > index a2b5fbba2d3b..750f4513fe20 100644 > --- a/drivers/input/joydev.c > +++ b/drivers/input/joydev.c > @@ -456,7 +456,7 @@ static int joydev_handle_JSIOCSAXMAP(struct joydev *joydev, > if (IS_ERR(abspam)) > return PTR_ERR(abspam); > > - for (i = 0; i < joydev->nabs; i++) { > + for (i = 0; i < len && i < joydev->nabs; i++) { > if (abspam[i] > ABS_MAX) { > retval = -EINVAL; > goto out; > @@ -487,7 +487,7 @@ static int joydev_handle_JSIOCSBTNMAP(struct joydev *joydev, > if (IS_ERR(keypam)) > return PTR_ERR(keypam); > > - for (i = 0; i < joydev->nkey; i++) { > + for (i = 0; i < (len / 2) && i < joydev->nkey; i++) { I think we also need to make sure that len is even. Do you mind if I add the check at the top of the function to return -EINVAL if it is odd? > if (keypam[i] > KEY_MAX || keypam[i] < BTN_MISC) { > retval = -EINVAL; > goto out; > -- > 2.30.0 > Thanks. -- Dmitry