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=-12.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 9285AC432BE for ; Wed, 18 Aug 2021 09:32:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7394E60551 for ; Wed, 18 Aug 2021 09:32:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233558AbhHRJdN (ORCPT ); Wed, 18 Aug 2021 05:33:13 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:39800 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233703AbhHRJcU (ORCPT ); Wed, 18 Aug 2021 05:32:20 -0400 Received: from relay2.suse.de (relay2.suse.de [149.44.160.134]) by smtp-out1.suse.de (Postfix) with ESMTP id 6BDC422065; Wed, 18 Aug 2021 09:31:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_rsa; t=1629279084; h=from:from:reply-to:reply-to:date:date:message-id:message-id:to:to: cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=MjEVLCKBlTSswofPN1pNmxlP19qpFPg2jUD4se0XdyA=; b=Vce+IAwmUDcfv2b7QGyi2Dv7EKo/Co6jwhdkPnVadZs3PhYLf7tUr6B9fRUUxtOcBZk6+N B9XQg+cRWkemeBBWnWGk1wfHVQuq5Xnz4OC/hrrv7YBobuFDHB3iZwPRwWeZB5fMRC+UY8 0ZVGoxSYWv4akI4SI4AnM5BUhMcP4k4= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.cz; s=susede2_ed25519; t=1629279084; h=from:from:reply-to:reply-to:date:date:message-id:message-id:to:to: cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=MjEVLCKBlTSswofPN1pNmxlP19qpFPg2jUD4se0XdyA=; b=SFOFKtThDem3M1F/rOZMlyJlFmdOZ4+c7ISuV48nRhjMQ1VbfvtT61ULNqlr3zoJHsVSVM ACnXbdzsW0b8HLBQ== Received: from ds.suse.cz (ds.suse.cz [10.100.12.205]) by relay2.suse.de (Postfix) with ESMTP id 4E36EA3B94; Wed, 18 Aug 2021 09:31:24 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id B0437DA72C; Wed, 18 Aug 2021 11:28:27 +0200 (CEST) Date: Wed, 18 Aug 2021 11:28:27 +0200 From: David Sterba To: Kees Cook Cc: linux-kernel@vger.kernel.org, Chris Mason , Josef Bacik , David Sterba , linux-btrfs@vger.kernel.org, "Gustavo A. R. Silva" , Greg Kroah-Hartman , Andrew Morton , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-staging@lists.linux.dev, linux-block@vger.kernel.org, linux-kbuild@vger.kernel.org, clang-built-linux@googlegroups.com, Rasmus Villemoes , linux-hardening@vger.kernel.org Subject: Re: [PATCH v2 49/63] btrfs: Use memset_startat() to clear end of struct Message-ID: <20210818092827.GO5047@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, Kees Cook , linux-kernel@vger.kernel.org, Chris Mason , Josef Bacik , David Sterba , linux-btrfs@vger.kernel.org, "Gustavo A. R. Silva" , Greg Kroah-Hartman , Andrew Morton , linux-wireless@vger.kernel.org, netdev@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-staging@lists.linux.dev, linux-block@vger.kernel.org, linux-kbuild@vger.kernel.org, clang-built-linux@googlegroups.com, Rasmus Villemoes , linux-hardening@vger.kernel.org References: <20210818060533.3569517-1-keescook@chromium.org> <20210818060533.3569517-50-keescook@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210818060533.3569517-50-keescook@chromium.org> User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 17, 2021 at 11:05:19PM -0700, Kees Cook wrote: > In preparation for FORTIFY_SOURCE performing compile-time and run-time > field bounds checking for memset(), avoid intentionally writing across > neighboring fields. > > Use memset_startat() so memset() doesn't get confused about writing > beyond the destination member that is intended to be the starting point > of zeroing through the end of the struct. > > Cc: Chris Mason > Cc: Josef Bacik > Cc: David Sterba > Cc: linux-btrfs@vger.kernel.org > Signed-off-by: Kees Cook Acked-by: David Sterba