From patchwork Thu Feb 20 11:13:02 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zheng Bin X-Patchwork-Id: 11393861 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 2898F924 for ; Thu, 20 Feb 2020 11:06:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 06DCB208C4 for ; Thu, 20 Feb 2020 11:06:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726952AbgBTLGA (ORCPT ); Thu, 20 Feb 2020 06:06:00 -0500 Received: from szxga05-in.huawei.com ([45.249.212.191]:10227 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726825AbgBTLGA (ORCPT ); Thu, 20 Feb 2020 06:06:00 -0500 Received: from DGGEMS406-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 7E7EA6C25229BF3A2F2C; Thu, 20 Feb 2020 19:05:53 +0800 (CST) Received: from huawei.com (10.90.53.225) by DGGEMS406-HUB.china.huawei.com (10.3.19.206) with Microsoft SMTP Server id 14.3.439.0; Thu, 20 Feb 2020 19:05:47 +0800 From: Zheng Bin To: , , , , CC: , Subject: [PATCH v2] xfs: add agf freeblocks verify in xfs_agf_verify Date: Thu, 20 Feb 2020 19:13:02 +0800 Message-ID: <1582197182-142137-1-git-send-email-zhengbin13@huawei.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 X-Originating-IP: [10.90.53.225] X-CFilter-Loop: Reflected Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org We recently used fuzz(hydra) to test XFS and automatically generate tmp.img(XFS v5 format, but some metadata is wrong) xfs_repair information(just one AG): agf_freeblks 0, counted 3224 in ag 0 agf_longest 536874136, counted 3224 in ag 0 sb_fdblocks 613, counted 3228 Test as follows: mount tmp.img tmpdir cp file1M tmpdir sync In 4.19-stable, sync will stuck, the reason is: xfs_mountfs xfs_check_summary_counts if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) || XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) && !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS)) return 0; -->just return, incore sb_fdblocks still be 613 xfs_initialize_perag_data cp file1M tmpdir -->ok(write file to pagecache) sync -->stuck(write pagecache to disk) xfs_map_blocks xfs_iomap_write_allocate while (count_fsb != 0) { nimaps = 0; while (nimaps == 0) { --> endless loop nimaps = 1; xfs_bmapi_write(..., &nimaps) --> nimaps becomes 0 again xfs_bmapi_write xfs_bmap_alloc xfs_bmap_btalloc xfs_alloc_vextent xfs_alloc_fix_freelist xfs_alloc_space_available -->fail(agf_freeblks is 0) In linux-next, sync not stuck, cause commit c2b3164320b5 ("xfs: use the latest extent at writeback delalloc conversion time") remove the above while, dmesg is as follows: [ 55.250114] XFS (loop0): page discard on page ffffea0008bc7380, inode 0x1b0c, offset 0. Users do not know why this page is discard, the better soultion is: 1. Like xfs_repair, make sure sb_fdblocks is equal to counted (xfs_initialize_perag_data did this, who is not called at this mount) 2. Add agf verify, if fail, will tell users to repair This patch use the second soultion. Signed-off-by: Zheng Bin Signed-off-by: Ren Xudong --- v1->v2: modify comment, add more agf verify fs/xfs/libxfs/xfs_alloc.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) -- 2.7.4 diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c index d8053bc..5faed42 100644 --- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -2839,6 +2839,7 @@ xfs_agf_verify( { struct xfs_mount *mp = bp->b_mount; struct xfs_agf *agf = XFS_BUF_TO_AGF(bp); + int i; if (xfs_sb_version_hascrc(&mp->m_sb)) { if (!uuid_equal(&agf->agf_uuid, &mp->m_sb.sb_meta_uuid)) @@ -2858,6 +2859,22 @@ xfs_agf_verify( be32_to_cpu(agf->agf_flcount) <= xfs_agfl_size(mp))) return __this_address; + if (be32_to_cpu(agf->agf_length) > mp->m_sb.sb_dblocks || + be32_to_cpu(agf->agf_btreeblks) > be32_to_cpu(agf->agf_length) || + be32_to_cpu(agf->agf_rmap_blocks) > be32_to_cpu(agf->agf_length) || + be32_to_cpu(agf->agf_refcount_blocks) > be32_to_cpu(agf->agf_length) || + be32_to_cpu(agf->agf_spare2) != 0) + return __this_address; + + for (i = 0; i < ARRAY_SIZE(agf->agf_spare64); i++) + if (be64_to_cpu(agf->agf_spare64[i]) != 0) + return __this_address; + + if (be32_to_cpu(agf->agf_freeblks) < be32_to_cpu(agf->agf_longest) || + be32_to_cpu(agf->agf_freeblks) > be32_to_cpu(agf->agf_length) || + be32_to_cpu(agf->agf_freeblks) > mp->m_sb.sb_fdblocks) + return __this_address; + if (be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) < 1 || be32_to_cpu(agf->agf_levels[XFS_BTNUM_CNT]) < 1 || be32_to_cpu(agf->agf_levels[XFS_BTNUM_BNO]) > XFS_BTREE_MAXLEVELS ||