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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9BAF8C433F5 for ; Fri, 18 Feb 2022 10:30:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232320AbiBRKbA (ORCPT ); Fri, 18 Feb 2022 05:31:00 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:53012 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231252AbiBRKbA (ORCPT ); Fri, 18 Feb 2022 05:31:00 -0500 Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [46.235.227.227]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2772F2B3562; Fri, 18 Feb 2022 02:30:43 -0800 (PST) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: usama.anjum) with ESMTPSA id 5FE561F466E3 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1645180241; bh=H7kO/4vrxYAqqmrH76Tul3nNx3Ly6WDoH9V/Wue96Dw=; h=Date:Cc:Subject:To:References:From:In-Reply-To:From; b=KdKNRkHDbRgYP1kAyhlwzlddsCTHjSMoJIFdixYjW/bTkkXzbTPe4x8tZxQSnWp+n mBWQHwGgtM5U+5etj1z0hir0ldgWRuQL8sslLNUKLvuYZA/z2u5DcJdi5pqeAaGF/8 yBgPF+2AjAeFvyci+kKTPQP8lnJOroZD9KJZq97DJjwhy49IjhzoxXIU5GkPKPnH6S Wyd9XLKyJ5oJRzbwhzVnEMY4PtRjYWKMj9o17/XM3yxgcNzA5O9FozAkhMExb/wnme xnBw2bl3C1E5Oa+7vX9GrnEFSQsyvyggbxU027AJiIqZONZPGtIoTu6UfOf+DmqSmn jlCR15BW9O5Xw== Message-ID: <762faf1b-0443-5ddf-4430-44a20cf2ec4d@collabora.com> Date: Fri, 18 Feb 2022 15:30:35 +0500 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Cc: usama.anjum@collabora.com, Arnd Bergmann , Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] lkdtm/usercopy: Expand size of "out of frame" object Content-Language: en-US To: Kees Cook References: <20220216201743.2088344-1-keescook@chromium.org> From: Muhammad Usama Anjum In-Reply-To: <20220216201743.2088344-1-keescook@chromium.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org On 2/17/22 1:17 AM, Kees Cook wrote: > To be sufficient out of range for the usercopy test to see the lifetime > mismatch, expand the size of the "bad" buffer, which will let it be > beyond current_stack_pointer regardless of stack growth direction. > Paired with the recent addition of stack depth checking under > CONFIG_HARDENED_USERCOPY=y, this will correctly start tripping again. > > Reported-by: Muhammad Usama Anjum > Cc: Arnd Bergmann > Cc: Greg Kroah-Hartman > Signed-off-by: Kees Cook Reviewed-by: Muhammad Usama Anjum