From nobody Fri Dec 19 20:12:25 2025 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 19B40C3A59D for ; Sat, 22 Oct 2022 07:55:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232186AbiJVHzz (ORCPT ); Sat, 22 Oct 2022 03:55:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54870 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231706AbiJVHwi (ORCPT ); Sat, 22 Oct 2022 03:52:38 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 17560AC297; Sat, 22 Oct 2022 00:46:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6790FB82DF6; Sat, 22 Oct 2022 07:39:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A54DCC433D7; Sat, 22 Oct 2022 07:39:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666424343; bh=51YjOXF7uUIpZAbLElBdbO797UG/6ZCUOY1Q/ovFfzc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1R+QU5QlqQOdXaZlu3FqBCt0jAZPRtqQCDAqLYlkj2L+x9V/Li6IZQqGEZRASguKL W94tfRELVzXeAF2BpoWy4wfsIcQWQfdaRXEIPLRpZwjxwbWWdm1Pc9cigjN85fnFU9 dWSPmxEKKkneFjNS2/LeSrCf4QN2cEUYYdRgl8qs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot , Tetsuo Handa , David Sterba Subject: [PATCH 5.19 111/717] btrfs: set generation before calling btrfs_clean_tree_block in btrfs_init_new_buffer Date: Sat, 22 Oct 2022 09:19:50 +0200 Message-Id: <20221022072435.073175744@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221022072415.034382448@linuxfoundation.org> References: <20221022072415.034382448@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Tetsuo Handa commit cbddcc4fa3443fe8cfb2ff8e210deb1f6a0eea38 upstream. syzbot is reporting uninit-value in btrfs_clean_tree_block() [1], for commit bc877d285ca3dba2 ("btrfs: Deduplicate extent_buffer init code") missed that btrfs_set_header_generation() in btrfs_init_new_buffer() must not be moved to after clean_tree_block() because clean_tree_block() is calling btrfs_header_generation() since commit 55c69072d6bd5be1 ("Btrfs: Fix extent_buffer usage when nodesize !=3D leafsize"). Since memzero_extent_buffer() will reset "struct btrfs_header" part, we can't move btrfs_set_header_generation() to before memzero_extent_buffer(). Just re-add btrfs_set_header_generation() before btrfs_clean_tree_block(). Link: https://syzkaller.appspot.com/bug?extid=3Dfba8e2116a12609b6c59 [1] Reported-by: syzbot Fixes: bc877d285ca3dba2 ("btrfs: Deduplicate extent_buffer init code") CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Tetsuo Handa Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/extent-tree.c | 3 +++ 1 file changed, 3 insertions(+) --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -4904,6 +4904,9 @@ btrfs_init_new_buffer(struct btrfs_trans !test_bit(BTRFS_ROOT_RESET_LOCKDEP_CLASS, &root->state)) lockdep_owner =3D BTRFS_FS_TREE_OBJECTID; =20 + /* btrfs_clean_tree_block() accesses generation field. */ + btrfs_set_header_generation(buf, trans->transid); + /* * This needs to stay, because we could allocate a freed block from an * old tree into a new tree, so we need to make sure this new block is