From patchwork Sat Mar 9 13:19:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhang Yi X-Patchwork-Id: 1053838 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-ext4-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=huawei.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 44GlGF6kBmz9s71 for ; Sun, 10 Mar 2019 00:15:01 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726296AbfCINO7 (ORCPT ); Sat, 9 Mar 2019 08:14:59 -0500 Received: from szxga04-in.huawei.com ([45.249.212.190]:4662 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726233AbfCINO7 (ORCPT ); Sat, 9 Mar 2019 08:14:59 -0500 Received: from DGGEMS404-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 7B562251A329D8EDCC2A; Sat, 9 Mar 2019 21:14:56 +0800 (CST) Received: from huawei.com (10.90.53.225) by DGGEMS404-HUB.china.huawei.com (10.3.19.204) with Microsoft SMTP Server id 14.3.408.0; Sat, 9 Mar 2019 21:14:47 +0800 From: "zhangyi (F)" To: CC: , , , , Subject: [PATCH] ext4: brelse all indirect buffers in ext4_ind_remove_space() Date: Sat, 9 Mar 2019 21:19:07 +0800 Message-ID: <1552137547-115352-1-git-send-email-yi.zhang@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-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org All indirect buffers get by ext4_find_shared() should be released no mater the branch should be freed or not. But now, we forget to release the lower depth indirect buffers when removing space from the same higher depth indirect block. It will lead to buffer leak and futher more, it may lead to quota information corruption when using old quota, consider the following case. - Create and mount an empty ext4 filesystem without extent and quota features, - quotacheck and enable the user & group quota, - Create some files and write some data to them, and then punch hole to some files of them, it may trigger the buffer leak problem mentioned above. - Disable quota and run quotacheck again, it will create two new aquota files and write the checked quota information to them, which probably may reuse the freed indirect block(the buffer and page cache was not freed) as data block. - Enable quota again, it will invoke vfs_load_quota_inode()->invalidate_bdev() to try to clean unused buffers and pagecache. Unfortunately, because of the buffer of quota data block is still referenced, quota code cannot read the up to date quota info from the device and lead to quota information corruption. This problem can be reproduced by xfstests generic/231 on ext3 file system or ext4 filesystem without extent and quota feature. This patch fix this problem by brelse all indirect buffers, and also do some cleanup of the brelse code in ext4_ind_remove_space(). Reported-by: Hulk Robot Signed-off-by: zhangyi (F) --- fs/ext4/indirect.c | 43 ++++++++++++++++++++++--------------------- 1 file changed, 22 insertions(+), 21 deletions(-) diff --git a/fs/ext4/indirect.c b/fs/ext4/indirect.c index bf7fa15..6f3f7d5 100644 --- a/fs/ext4/indirect.c +++ b/fs/ext4/indirect.c @@ -1219,6 +1219,7 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, ext4_lblk_t offsets[4], offsets2[4]; Indirect chain[4], chain2[4]; Indirect *partial, *partial2; + Indirect *p = NULL, *p2 = NULL; ext4_lblk_t max_block; __le32 nr = 0, nr2 = 0; int n = 0, n2 = 0; @@ -1260,7 +1261,7 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, } - partial = ext4_find_shared(inode, n, offsets, chain, &nr); + partial = p = ext4_find_shared(inode, n, offsets, chain, &nr); if (nr) { if (partial == chain) { /* Shared branch grows from the inode */ @@ -1285,13 +1286,11 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, partial->p + 1, (__le32 *)partial->bh->b_data+addr_per_block, (chain+n-1) - partial); - BUFFER_TRACE(partial->bh, "call brelse"); - brelse(partial->bh); partial--; } end_range: - partial2 = ext4_find_shared(inode, n2, offsets2, chain2, &nr2); + partial2 = p2 = ext4_find_shared(inode, n2, offsets2, chain2, &nr2); if (nr2) { if (partial2 == chain2) { /* @@ -1321,16 +1320,14 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, (__le32 *)partial2->bh->b_data, partial2->p, (chain2+n2-1) - partial2); - BUFFER_TRACE(partial2->bh, "call brelse"); - brelse(partial2->bh); partial2--; } goto do_indirects; } /* Punch happened within the same level (n == n2) */ - partial = ext4_find_shared(inode, n, offsets, chain, &nr); - partial2 = ext4_find_shared(inode, n2, offsets2, chain2, &nr2); + partial = p = ext4_find_shared(inode, n, offsets, chain, &nr); + partial2 = p2 = ext4_find_shared(inode, n2, offsets2, chain2, &nr2); /* Free top, but only if partial2 isn't its subtree. */ if (nr) { @@ -1387,11 +1384,7 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, partial->p + 1, partial2->p, (chain+n-1) - partial); - BUFFER_TRACE(partial->bh, "call brelse"); - brelse(partial->bh); - BUFFER_TRACE(partial2->bh, "call brelse"); - brelse(partial2->bh); - return 0; + goto clean_up; } /* @@ -1406,8 +1399,6 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, partial->p + 1, (__le32 *)partial->bh->b_data+addr_per_block, (chain+n-1) - partial); - BUFFER_TRACE(partial->bh, "call brelse"); - brelse(partial->bh); partial--; } if (partial2 > chain2 && depth2 <= depth) { @@ -1415,11 +1406,21 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, (__le32 *)partial2->bh->b_data, partial2->p, (chain2+n2-1) - partial2); - BUFFER_TRACE(partial2->bh, "call brelse"); - brelse(partial2->bh); partial2--; } } + +clean_up: + while (p && p > chain) { + BUFFER_TRACE(p->bh, "call brelse"); + brelse(p->bh); + p--; + } + while (p2 && p2 > chain2) { + BUFFER_TRACE(p2->bh, "call brelse"); + brelse(p2->bh); + p2--; + } return 0; do_indirects: @@ -1427,7 +1428,7 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, switch (offsets[0]) { default: if (++n >= n2) - return 0; + break; nr = i_data[EXT4_IND_BLOCK]; if (nr) { ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 1); @@ -1435,7 +1436,7 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, } case EXT4_IND_BLOCK: if (++n >= n2) - return 0; + break; nr = i_data[EXT4_DIND_BLOCK]; if (nr) { ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 2); @@ -1443,7 +1444,7 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, } case EXT4_DIND_BLOCK: if (++n >= n2) - return 0; + break; nr = i_data[EXT4_TIND_BLOCK]; if (nr) { ext4_free_branches(handle, inode, NULL, &nr, &nr+1, 3); @@ -1452,5 +1453,5 @@ int ext4_ind_remove_space(handle_t *handle, struct inode *inode, case EXT4_TIND_BLOCK: ; } - return 0; + goto clean_up; }