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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 D67BAC432C0 for ; Fri, 22 Nov 2019 10:37:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AB5F020707 for ; Fri, 22 Nov 2019 10:37:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574419063; bh=NGvcGUUb/zX84EsKjg1TLdH6Al2JKVLtjEr2dAXuSVE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=R7Mq1XpwqZInMmzXYgmNAucPVlnW/ZtYDkhLH79eiEYB8fgaOqEcYRRtOWQSfpzHf TSG4d/tuoFmny0MNdiP4xkLit+mjzMEKuIwKjw7Xcb2cidA8kAAF3mkmr80RlnCmbg Ncxj9rhBAitsC+l5UM3YcS1GSNeP3YsaqBILNGEk= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727361AbfKVKhm (ORCPT ); Fri, 22 Nov 2019 05:37:42 -0500 Received: from mail.kernel.org ([198.145.29.99]:39428 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727362AbfKVKhk (ORCPT ); Fri, 22 Nov 2019 05:37:40 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 E7B4220707; Fri, 22 Nov 2019 10:37:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574419059; bh=NGvcGUUb/zX84EsKjg1TLdH6Al2JKVLtjEr2dAXuSVE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KcsfveKXsU0EO0zYbckJdmrlr/ALbQZ1P5D8CFYu6QyXutEMcxkLTOin92QaFV6YC auFiROkptBm1cepOcv7H03NAJAoROg7SZ+hRccalHkH00J6Pmggka6U28Ws+1fAVxB 0u8s6Y6xoanUn6qfL3KvJmzqNYmlPgzFhyvl9YIA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dan Carpenter , Peter Malone , Philippe Ombredanne , Mathieu Malaterre , Bartlomiej Zolnierkiewicz , Sasha Levin Subject: [PATCH 4.4 143/159] fbdev: sbuslib: integer overflow in sbusfb_ioctl_helper() Date: Fri, 22 Nov 2019 11:28:54 +0100 Message-Id: <20191122100838.403706593@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191122100704.194776704@linuxfoundation.org> References: <20191122100704.194776704@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dan Carpenter [ Upstream commit e5017716adb8aa5c01c52386c1b7470101ffe9c5 ] The "index + count" addition can overflow. Both come directly from the user. This bug leads to an information leak. Signed-off-by: Dan Carpenter Cc: Peter Malone Cc: Philippe Ombredanne Cc: Mathieu Malaterre Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Sasha Levin --- drivers/video/fbdev/sbuslib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/video/fbdev/sbuslib.c b/drivers/video/fbdev/sbuslib.c index b425718925c01..52e161dbd2047 100644 --- a/drivers/video/fbdev/sbuslib.c +++ b/drivers/video/fbdev/sbuslib.c @@ -170,7 +170,7 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg, get_user(ublue, &c->blue)) return -EFAULT; - if (index + count > cmap->len) + if (index > cmap->len || count > cmap->len - index) return -EINVAL; for (i = 0; i < count; i++) { -- 2.20.1