From patchwork Fri Feb 21 04:47:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zheng Bin X-Patchwork-Id: 11395543 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 6404013A4 for ; Fri, 21 Feb 2020 04:40:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4413F222C4 for ; Fri, 21 Feb 2020 04:40:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729667AbgBUEkN (ORCPT ); Thu, 20 Feb 2020 23:40:13 -0500 Received: from szxga06-in.huawei.com ([45.249.212.32]:43070 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729229AbgBUEkN (ORCPT ); Thu, 20 Feb 2020 23:40:13 -0500 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.60]) by Forcepoint Email with ESMTP id 3D5AB1C728F956295E84; Fri, 21 Feb 2020 12:40:10 +0800 (CST) Received: from huawei.com (10.90.53.225) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.439.0; Fri, 21 Feb 2020 12:40:00 +0800 From: Zheng Bin To: , , , , CC: , Subject: [PATCH v3] xfs: add agf freeblocks verify in xfs_agf_verify Date: Fri, 21 Feb 2020 12:47:15 +0800 Message-ID: <1582260435-20939-1-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 Reviewed-by: Darrick J. Wong --- v1->v2: modify comment, add more agf verify v2->v3: modify code which is suggested by hellwig & darrick besides, remove the agf_freeblks < sb_fdblocks check, sb_fdblocks may not be true, if we have lazysbcount or not umount clean. If we check this, we need to add if ((!xfs_sb_version_haslazysbcount(&mp->m_sb) || XFS_LAST_UNMOUNT_WAS_CLEAN(mp)) && !xfs_fs_has_sickness(mp, XFS_SICK_FS_COUNTERS)) like function xfs_check_summary_counts does. fs/xfs/libxfs/xfs_alloc.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) -- 2.7.4 diff --git a/fs/xfs/libxfs/xfs_alloc.c b/fs/xfs/libxfs/xfs_alloc.c index d8053bc..183dc25 100644 --- a/fs/xfs/libxfs/xfs_alloc.c +++ b/fs/xfs/libxfs/xfs_alloc.c @@ -2858,6 +2858,13 @@ 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) + 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)) + 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 || @@ -2869,6 +2876,10 @@ xfs_agf_verify( be32_to_cpu(agf->agf_levels[XFS_BTNUM_RMAP]) > XFS_BTREE_MAXLEVELS)) return __this_address; + if (xfs_sb_version_hasrmapbt(&mp->m_sb) && + be32_to_cpu(agf->agf_rmap_blocks) > be32_to_cpu(agf->agf_length)) + return __this_address; + /* * during growfs operations, the perag is not fully initialised, * so we can't use it for any useful checking. growfs ensures we can't @@ -2883,6 +2894,11 @@ xfs_agf_verify( return __this_address; if (xfs_sb_version_hasreflink(&mp->m_sb) && + be32_to_cpu(agf->agf_refcount_blocks) > + be32_to_cpu(agf->agf_length)) + return __this_address; + + if (xfs_sb_version_hasreflink(&mp->m_sb) && (be32_to_cpu(agf->agf_refcount_level) < 1 || be32_to_cpu(agf->agf_refcount_level) > XFS_BTREE_MAXLEVELS)) return __this_address;