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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 65158C43331 for ; Wed, 13 Nov 2019 02:02:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 35A5722466 for ; Wed, 13 Nov 2019 02:02:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573610557; bh=NGvcGUUb/zX84EsKjg1TLdH6Al2JKVLtjEr2dAXuSVE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=Erpe9lhl3V6H4sFen0a6sc5ngky/4aJuT8g0y2hfK3HUkAWJ89taDCv0c90pYX6P8 XhjMWT3sVnxxDqS5zkmmAbOqsVi/ONbHyo1E6KHm2TWkccSNss0YAhko+Xz30HJkuD fWobuIysycr/DaJ8jGAmv//JAyDrcF2Y9CUY+tXs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728854AbfKMCCg (ORCPT ); Tue, 12 Nov 2019 21:02:36 -0500 Received: from mail.kernel.org ([198.145.29.99]:59062 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730094AbfKMCC3 (ORCPT ); Tue, 12 Nov 2019 21:02:29 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A94E5222CA; Wed, 13 Nov 2019 02:02:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573610548; bh=NGvcGUUb/zX84EsKjg1TLdH6Al2JKVLtjEr2dAXuSVE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=P88yY1P7UAi7xs9N4k5ebC62VmgWOLcsqDOhJdyorYBe5DrsO+7JfgHEZBaEJO6hx q/zMhCEmUNKGZp6k/EoUv5v4995DEE5cuQDOfxszxtEU0r/koTjV13uEH3lEk3ucB9 WHFB7BUq2DDtBSGdRJhCx/LqUyrugq1iGdRlBOR4= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dan Carpenter , Peter Malone , Philippe Ombredanne , Mathieu Malaterre , Bartlomiej Zolnierkiewicz , Sasha Levin , dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 33/48] fbdev: sbuslib: integer overflow in sbusfb_ioctl_helper() Date: Tue, 12 Nov 2019 21:01:16 -0500 Message-Id: <20191113020131.13356-33-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191113020131.13356-1-sashal@kernel.org> References: <20191113020131.13356-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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