From patchwork Tue Oct 29 18:23:20 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 11218425 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2D6DA1515 for ; Tue, 29 Oct 2019 18:24:58 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 13BA620679 for ; Tue, 29 Oct 2019 18:24:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 13BA620679 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 12C1B6E50B; Tue, 29 Oct 2019 18:24:56 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from userp2130.oracle.com (userp2130.oracle.com [156.151.31.86]) by gabe.freedesktop.org (Postfix) with ESMTPS id 50EE46E50B for ; Tue, 29 Oct 2019 18:24:55 +0000 (UTC) Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x9TI5FDj175951; Tue, 29 Oct 2019 18:23:40 GMT Received: from aserp3020.oracle.com (aserp3020.oracle.com [141.146.126.70]) by userp2130.oracle.com with ESMTP id 2vvdjub9ee-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 29 Oct 2019 18:23:39 +0000 Received: from pps.filterd (aserp3020.oracle.com [127.0.0.1]) by aserp3020.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x9TI8BBK179764; Tue, 29 Oct 2019 18:23:39 GMT Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by aserp3020.oracle.com with ESMTP id 2vxpfdgt2e-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 29 Oct 2019 18:23:39 +0000 Received: from abhmp0016.oracle.com (abhmp0016.oracle.com [141.146.116.22]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x9TINU14011472; Tue, 29 Oct 2019 18:23:30 GMT Received: from mwanda (/41.57.98.10) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 29 Oct 2019 11:23:30 -0700 Date: Tue, 29 Oct 2019 21:23:20 +0300 From: Dan Carpenter To: Bartlomiej Zolnierkiewicz , Andrea Righi Subject: [PATCH] fbdev: potential information leak in do_fb_ioctl() Message-ID: <20191029182320.GA17569@mwanda> MIME-Version: 1.0 Content-Disposition: inline X-Mailer: git-send-email haha only kidding User-Agent: Mutt/1.10.1 (2018-07-13) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9425 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910290160 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9425 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1908290000 definitions=main-1910290160 X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : mime-version : content-type; s=corp-2019-08-05; bh=pvaGyOZDLlNqbGIv4aiDa+8jV2u8TRmd0Sg/3CdaYfQ=; b=GayfmIV97A/7KomJSAsydyBuszzE+3RDo1LCbszbUU03PKeOPpUsle4oX8Bz1eM7+QTg w17fUSx26ItlguIpsL8eUG0ZQzM19hMSpsyOjpclWpMjsMwnIU1OJ0G/0HZ9jt9TcWPu nc2WRwGPQVL9Ox2RSIbuHMSbPWSSss3mVfWN2ZOT14JMBpQIsvN3gB/FH1OC1i7XgMgI pKVgT+27FvJ6I9IkQhR7tVJmBVx3R9ZIPK8kaaHl/VEpXSNaajWQENUJs13sEKJacAWV fQuop4wCqvSb1Q1wLkFTAlw40mAmIgY55WNYNdaRCm4j8RVgdThKmUpTxLYJCbEjnlRz Jw== X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fbdev@vger.kernel.org, security@kernel.org, Kees Cook , kernel-janitors@vger.kernel.org, Daniel Vetter , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Julia Lawall , Gerd Hoffmann , Sam Ravnborg , Peter Rosin Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" The "fix" struct has a 2 byte hole after ->ywrapstep and the "fix = info->fix;" assignment doesn't necessarily clear it. It depends on the compiler. Fixes: 1f5e31d7e55a ("fbmem: don't call copy_from/to_user() with mutex held") Signed-off-by: Dan Carpenter --- I have 13 more similar places to patch... I'm not totally sure I understand all the issues involved. drivers/video/fbdev/core/fbmem.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index 6f6fc785b545..b4ce6a28aed9 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -1109,6 +1109,7 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd, ret = -EFAULT; break; case FBIOGET_FSCREENINFO: + memset(&fix, 0, sizeof(fix)); lock_fb_info(info); fix = info->fix; if (info->flags & FBINFO_HIDE_SMEM_START)