From nobody Sat Sep 27 20:18:54 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 06378C32772 for ; Tue, 23 Aug 2022 10:27:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353644AbiHWK04 (ORCPT ); Tue, 23 Aug 2022 06:26:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46774 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1353639AbiHWKLq (ORCPT ); Tue, 23 Aug 2022 06:11:46 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 26792719AF; Tue, 23 Aug 2022 01:57:53 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 494436153F; Tue, 23 Aug 2022 08:57:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 52F7EC433C1; Tue, 23 Aug 2022 08:57:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1661245071; bh=IYZO8npxWKcX2UbrOdmes4WW/OzWUgGzMI1e69PPBiI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CSYd3+ZCaSeBuDk5PzoBbHUl2ixMv5erPpclvp5CrvcJtycFzhu2vccmFcmaqETkp I4b+ECD68Nde1CwgkK0i8Hel0sv4vba82TGSrQKarLZQbleDTX0M+10eAi34J2DpOV SRTN/rCuGKNldahLsip9/EAMxErtYHNHfIZxspnA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Oleg Kiselev , Theodore Tso , Sasha Levin Subject: [PATCH 5.15 205/244] ext4: avoid resizing to a partial cluster size Date: Tue, 23 Aug 2022 10:26:04 +0200 Message-Id: <20220823080106.344497069@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220823080059.091088642@linuxfoundation.org> References: <20220823080059.091088642@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: Kiselev, Oleg [ Upstream commit 69cb8e9d8cd97cdf5e293b26d70a9dee3e35e6bd ] This patch avoids an attempt to resize the filesystem to an unaligned cluster boundary. An online resize to a size that is not integral to cluster size results in the last iteration attempting to grow the fs by a negative amount, which trips a BUG_ON and leaves the fs with a corrupted in-memory superblock. Signed-off-by: Oleg Kiselev Link: https://lore.kernel.org/r/0E92A0AB-4F16-4F1A-94B7-702CC6504FDE@amazon= .com Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/ext4/resize.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/fs/ext4/resize.c b/fs/ext4/resize.c index fa3c854125bb..862cbbc01d6e 100644 --- a/fs/ext4/resize.c +++ b/fs/ext4/resize.c @@ -1977,6 +1977,16 @@ int ext4_resize_fs(struct super_block *sb, ext4_fsbl= k_t n_blocks_count) } brelse(bh); =20 + /* + * For bigalloc, trim the requested size to the nearest cluster + * boundary to avoid creating an unusable filesystem. We do this + * silently, instead of returning an error, to avoid breaking + * callers that blindly resize the filesystem to the full size of + * the underlying block device. + */ + if (ext4_has_feature_bigalloc(sb)) + n_blocks_count &=3D ~((1 << EXT4_CLUSTER_BITS(sb)) - 1); + retry: o_blocks_count =3D ext4_blocks_count(es); =20 --=20 2.35.1