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=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 0AFE6C43331 for ; Wed, 13 Nov 2019 01:58:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D08A22245A for ; Wed, 13 Nov 2019 01:58:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573610328; bh=6tKVNmbw+qYOY0gZtKFGEPhIaxF5nM+KLL6j78blHzQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=j7rCrFbuzzR9TCeD/SLn9Vm9no9EkiF9CgUHJKCGCke954sQAI27ezmp0O9rl+zAQ tDr3WMkgg3jmb3cOngv2lPHO6zzlI+7MO8wmWuMhAeO038/zgJwqC4ro1p6wRPW0xM LYHO4uMwqDK0NMHque6ywvmsWBL4Bz/Kp2DHRbdU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730118AbfKMB6s (ORCPT ); Tue, 12 Nov 2019 20:58:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:52624 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728779AbfKMB6m (ORCPT ); Tue, 12 Nov 2019 20:58:42 -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 C7BA62245C; Wed, 13 Nov 2019 01:58:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573610321; bh=6tKVNmbw+qYOY0gZtKFGEPhIaxF5nM+KLL6j78blHzQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=L3JnJItqYYqeKBw5kgf/lQXEJmpnX3GMIvxLHgn+6eRgO9NQJWfoDiN+2d1rWytit dgzTuimBUlZChOwkT1XGfJQIj+SPzlas2hV/VC0VNRes8a/pmuSSQWQy/rAu1QE9Jr GD+IpZvtZ6uTGVDbN1AmfIrifYx3DRM44thrL+9A= 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 4.14 083/115] fbdev: sbuslib: integer overflow in sbusfb_ioctl_helper() Date: Tue, 12 Nov 2019 20:55:50 -0500 Message-Id: <20191113015622.11592-83-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191113015622.11592-1-sashal@kernel.org> References: <20191113015622.11592-1-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 90c51330969c2..01a7110e61a76 100644 --- a/drivers/video/fbdev/sbuslib.c +++ b/drivers/video/fbdev/sbuslib.c @@ -171,7 +171,7 @@ 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