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=-16.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 40EB3C43214 for ; Sun, 22 Aug 2021 07:56:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E511B61051 for ; Sun, 22 Aug 2021 07:56:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org E511B61051 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 9AEEE8D0002; Sun, 22 Aug 2021 03:56:57 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 927E88D0005; Sun, 22 Aug 2021 03:56:57 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 691648D0001; Sun, 22 Aug 2021 03:56:57 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0215.hostedemail.com [216.40.44.215]) by kanga.kvack.org (Postfix) with ESMTP id 4B8998D0002 for ; Sun, 22 Aug 2021 03:56:57 -0400 (EDT) Received: from smtpin13.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 05316274C4 for ; Sun, 22 Aug 2021 07:56:57 +0000 (UTC) X-FDA: 78501960474.13.0A46ECD Received: from mail-pj1-f50.google.com (mail-pj1-f50.google.com [209.85.216.50]) by imf18.hostedemail.com (Postfix) with ESMTP id B45F74002087 for ; Sun, 22 Aug 2021 07:56:56 +0000 (UTC) Received: by mail-pj1-f50.google.com with SMTP id n13-20020a17090a4e0d00b0017946980d8dso16615047pjh.5 for ; Sun, 22 Aug 2021 00:56:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=CkbCUqYXpxKrv+E9RWgklPDu42LROG49HfEVFdt9oJ8=; b=Lis4BwQuqQ5AiwLz0OPNa6NcDbii0sWFsfkJxxc/gLG4M5F6KFpFw0OwJAU4LLha1Y 1VHPMCZBH6hQE8HwtdR6ByL1XQdmTyML/R1CZcj+jmjFz6FmyH8fCprGSTibSI3S7ckw dd651MGZpPUZCJD0eAyGjZ0erQ4aAMTYI08V4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=CkbCUqYXpxKrv+E9RWgklPDu42LROG49HfEVFdt9oJ8=; b=QYOUs7QFn79cF1V+23xuFH5lnPFaRUMaxQb73UvAkvK8c53NhORUGXLaipqPx9YzLc rHL4nlSNZe18FUIh5QKIBa+IzjiTjKOt5+tYz/c8OcdODG7DruSFNJbj1HWM9qVPvlXU 3a4o1micZinkCHGRWnVrKDBvumOYB0Ktlq0rjmVS2VJ2+uQxy+K9jmGan/NVDy3TqQPJ j/Z+mK3lbKccCU4VqvR0+gaU76ywZ+rNx8ZB02YhjDcbVhBIMtOGTuSKfDIhp/8XDHfl 3RIhxcHD85eYYvh3ywTshrcI/BHzy9owq5TthKG5JeLsQ/wuxR3ng9UchKmtxGaSDhN+ +ugw== X-Gm-Message-State: AOAM530QWFk5L/2k8Igunv7XLAWQDgPH8e6sQhFlfIBLsVwYN1YOH4ZE Y7URgNoW16sj3Vhrn/6iq5qfSg== X-Google-Smtp-Source: ABdhPJxMh0tsIpdLIetjZVeqwrL9nLQwgUFzp8AC30tGZZ5VwIWzP27ar8snqC6juFu+yovM8qX/ZA== X-Received: by 2002:a17:902:8606:b029:12c:2625:76cf with SMTP id f6-20020a1709028606b029012c262576cfmr23579503plo.17.1629619015880; Sun, 22 Aug 2021 00:56:55 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id w2sm10588697pjq.5.2021.08.22.00.56.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 22 Aug 2021 00:56:55 -0700 (PDT) From: Kees Cook To: linux-kernel@vger.kernel.org Cc: Kees Cook , Nikolay Borisov , David Sterba , Rasmus Villemoes , Daniel Micay , Francis Laniel , Bart Van Assche , David Gow , linux-mm@kvack.org, clang-built-linux@googlegroups.com, linux-hardening@vger.kernel.org Subject: [PATCH for-next 25/25] btrfs: Use memset_startat() to clear end of struct Date: Sun, 22 Aug 2021 00:51:22 -0700 Message-Id: <20210822075122.864511-26-keescook@chromium.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210822075122.864511-1-keescook@chromium.org> References: <20210822075122.864511-1-keescook@chromium.org> MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=1155; h=from:subject; bh=XHjqu1RreJZUS0lhfMO2nlVUCup75rB1cNpejDSomCQ=; b=owEBbQKS/ZANAwAKAYly9N/cbcAmAcsmYgBhIgH6ZxQKCftHw+bbIsZDc7/cNC2VaaPC/Bzvi8PJ jBI2gduJAjMEAAEKAB0WIQSlw/aPIp3WD3I+bhOJcvTf3G3AJgUCYSIB+gAKCRCJcvTf3G3AJlX6D/ 0ccDotcFu1yUXFehzHwNXSmCdP2dRq6MGepK0y703lxGRgYRXH8mgO0Xcee95Lf1qk9czxzNowS6Go sS7b4Pkw/E9zlTldMaPdOl2QcI5czJx7DD1K4TcjXVJIFmS6pKUwT+eyjq0GxpYr7UP56JMbPUEqe5 /FFM82ogo5GKXC7ZpnDH0SAN0vm6d6FA+qTuz09iEWwG/fISmVDLNgt5/5XHX+FBNT9x7tglj+UGJo J1LFFMUYLrtM2xP6W7KZ2dSwVZJXgKwar1gnOJNrESpF5p0R3pv662l39w1R5CaPsMt7yCRg/dKY83 xPpJ6QS6fappboPIqlmH5DsKrwK5tkqUZOo965oL22gXqQLlJrDFBpS+HcA90K77tmUDHw0cA1oZCj xEMwTwSaEaYhTUAETc8W+rxxhHOoWltHARk5AyjoMLUAB9R97PZJqtlzmw3T+LCpHan7/53N3wtmDo twQpqQVoR6GDsE+DDBy0ofV2si8wOgHKYzXDMIJhJ35Axs/8MT4SZe+NZy84FF+nL8DpWAWNa/4QPj +lqLt0IFYNIrpylbCHV7Fr8Rw7AwdoPxNmNyLThTwo3dPw1G+ZNgvqLhqFDYZIQiBRh8ruca3dYIvv JSKCxSme2hIV5U+VcQHoQKeTVwGooGQAZsYFH1gkRt9Apq6nbH2JORDnJ6kQ== X-Developer-Key: i=keescook@chromium.org; a=openpgp; fpr=A5C3F68F229DD60F723E6E138972F4DFDC6DC026 Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=chromium.org header.s=google header.b=Lis4BwQu; spf=pass (imf18.hostedemail.com: domain of keescook@chromium.org designates 209.85.216.50 as permitted sender) smtp.mailfrom=keescook@chromium.org; dmarc=pass (policy=none) header.from=chromium.org X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: B45F74002087 X-Stat-Signature: i5y9jhwop8s1q9rmq5fukdm3y5tmmp8b X-HE-Tag: 1629619016-760974 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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. Reviewed-by: Nikolay Borisov Acked-by: David Sterba Signed-off-by: Kees Cook --- fs/btrfs/root-tree.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c index 702dc5441f03..12ceb14a1141 100644 --- a/fs/btrfs/root-tree.c +++ b/fs/btrfs/root-tree.c @@ -39,10 +39,8 @@ static void btrfs_read_root_item(struct extent_buffer = *eb, int slot, need_reset =3D 1; } if (need_reset) { - memset(&item->generation_v2, 0, - sizeof(*item) - offsetof(struct btrfs_root_item, - generation_v2)); - + /* Clear all members from generation_v2 onwards. */ + memset_startat(item, 0, generation_v2); generate_random_guid(item->uuid); } } --=20 2.30.2