From patchwork Thu Dec 21 15:05:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baokun Li X-Patchwork-Id: 1879202 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=ozlabs.org (client-ip=150.107.74.76; helo=gandalf.ozlabs.org; envelope-from=srs0=9qav=ia=vger.kernel.org=linux-ext4+bounces-536-patchwork-incoming=ozlabs.org@ozlabs.org; receiver=patchwork.ozlabs.org) Received: from gandalf.ozlabs.org (gandalf.ozlabs.org [150.107.74.76]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4Swtx94WDlz1ySd for ; Fri, 22 Dec 2023 02:03:57 +1100 (AEDT) Received: from gandalf.ozlabs.org (mail.ozlabs.org [IPv6:2404:9400:2221:ea00::3]) by gandalf.ozlabs.org (Postfix) with ESMTP id 4Swtx93qdQz4wcH for ; Fri, 22 Dec 2023 02:03:57 +1100 (AEDT) Received: by gandalf.ozlabs.org (Postfix) id 4Swtx93j0Bz4wcM; Fri, 22 Dec 2023 02:03:57 +1100 (AEDT) Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: gandalf.ozlabs.org; dmarc=fail (p=quarantine dis=none) header.from=huawei.com Authentication-Results: gandalf.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=147.75.199.223; helo=ny.mirrors.kernel.org; envelope-from=linux-ext4+bounces-536-patchwork-incoming=ozlabs.org@vger.kernel.org; receiver=ozlabs.org) Received: from ny.mirrors.kernel.org (ny.mirrors.kernel.org [147.75.199.223]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) by gandalf.ozlabs.org (Postfix) with ESMTPS id 4Swtx91ltJz4wcH for ; Fri, 22 Dec 2023 02:03:57 +1100 (AEDT) Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ny.mirrors.kernel.org (Postfix) with ESMTPS id 69BA31C241E1 for ; Thu, 21 Dec 2023 15:03:55 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id B52BC55E7F; Thu, 21 Dec 2023 15:02:49 +0000 (UTC) X-Original-To: linux-ext4@vger.kernel.org Received: from szxga07-in.huawei.com (szxga07-in.huawei.com [45.249.212.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8EC3C55E5E; Thu, 21 Dec 2023 15:02:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.163.17]) by szxga07-in.huawei.com (SkyGuard) with ESMTP id 4SwttF1t6Nz1R5cK; Thu, 21 Dec 2023 23:01:25 +0800 (CST) Received: from dggpeml500021.china.huawei.com (unknown [7.185.36.21]) by mail.maildlp.com (Postfix) with ESMTPS id 3D98B1A0172; Thu, 21 Dec 2023 23:02:40 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpeml500021.china.huawei.com (7.185.36.21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.35; Thu, 21 Dec 2023 23:02:39 +0800 From: Baokun Li To: CC: , , , , , , , , Subject: [PATCH v2 5/8] ext4: avoid dividing by 0 in mb_update_avg_fragment_size() when block bitmap corrupt Date: Thu, 21 Dec 2023 23:05:55 +0800 Message-ID: <20231221150558.2740823-6-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20231221150558.2740823-1-libaokun1@huawei.com> References: <20231221150558.2740823-1-libaokun1@huawei.com> Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpeml500021.china.huawei.com (7.185.36.21) Determine if bb_fragments is 0 instead of determining bb_free to eliminate the risk of dividing by zero when the block bitmap is corrupted. Signed-off-by: Baokun Li Reviewed-by: Jan Kara --- fs/ext4/mballoc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 1f15774971d7..03500aec43ac 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -842,7 +842,7 @@ mb_update_avg_fragment_size(struct super_block *sb, struct ext4_group_info *grp) struct ext4_sb_info *sbi = EXT4_SB(sb); int new_order; - if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_free == 0) + if (!test_opt2(sb, MB_OPTIMIZE_SCAN) || grp->bb_fragments == 0) return; new_order = mb_avg_fragment_size_order(sb,