From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756308AbcAXWLR (ORCPT ); Sun, 24 Jan 2016 17:11:17 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:32804 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754266AbcAXWFR (ORCPT ); Sun, 24 Jan 2016 17:05:17 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Joseph Qi , Mark Fasheh , Joel Becker , Andrew Morton , Linus Torvalds , Luis Henriques Subject: [PATCH 3.16.y-ckt 108/128] ocfs2: fix BUG when calculate new backup super Date: Sun, 24 Jan 2016 22:01:03 +0000 Message-Id: <1453672883-2708-109-git-send-email-luis.henriques@canonical.com> In-Reply-To: <1453672883-2708-1-git-send-email-luis.henriques@canonical.com> References: <1453672883-2708-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt23 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Joseph Qi commit 5c9ee4cbf2a945271f25b89b137f2c03bbc3be33 upstream. When resizing, it firstly extends the last gd. Once it should backup super in the gd, it calculates new backup super and update the corresponding value. But it currently doesn't consider the situation that the backup super is already done. And in this case, it still sets the bit in gd bitmap and then decrease from bg_free_bits_count, which leads to a corrupted gd and trigger the BUG in ocfs2_block_group_set_bits: BUG_ON(le16_to_cpu(bg->bg_free_bits_count) < num_bits); So check whether the backup super is done and then do the updates. Signed-off-by: Joseph Qi Reviewed-by: Jiufei Xue Reviewed-by: Yiwen Jiang Cc: Mark Fasheh Cc: Joel Becker Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Luis Henriques --- fs/ocfs2/resize.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/fs/ocfs2/resize.c b/fs/ocfs2/resize.c index d5da6f624142..79b8021302b3 100644 --- a/fs/ocfs2/resize.c +++ b/fs/ocfs2/resize.c @@ -54,11 +54,12 @@ static u16 ocfs2_calc_new_backup_super(struct inode *inode, struct ocfs2_group_desc *gd, u16 cl_cpg, + u16 old_bg_clusters, int set) { int i; u16 backups = 0; - u32 cluster; + u32 cluster, lgd_cluster; u64 blkno, gd_blkno, lgd_blkno = le64_to_cpu(gd->bg_blkno); for (i = 0; i < OCFS2_MAX_BACKUP_SUPERBLOCKS; i++) { @@ -71,6 +72,12 @@ static u16 ocfs2_calc_new_backup_super(struct inode *inode, else if (gd_blkno > lgd_blkno) break; + /* check if already done backup super */ + lgd_cluster = ocfs2_blocks_to_clusters(inode->i_sb, lgd_blkno); + lgd_cluster += old_bg_clusters; + if (lgd_cluster >= cluster) + continue; + if (set) ocfs2_set_bit(cluster % cl_cpg, (unsigned long *)gd->bg_bitmap); @@ -99,6 +106,7 @@ static int ocfs2_update_last_group_and_inode(handle_t *handle, u16 chain, num_bits, backups = 0; u16 cl_bpc = le16_to_cpu(cl->cl_bpc); u16 cl_cpg = le16_to_cpu(cl->cl_cpg); + u16 old_bg_clusters; trace_ocfs2_update_last_group_and_inode(new_clusters, first_new_cluster); @@ -112,6 +120,7 @@ static int ocfs2_update_last_group_and_inode(handle_t *handle, group = (struct ocfs2_group_desc *)group_bh->b_data; + old_bg_clusters = le16_to_cpu(group->bg_bits) / cl_bpc; /* update the group first. */ num_bits = new_clusters * cl_bpc; le16_add_cpu(&group->bg_bits, num_bits); @@ -125,7 +134,7 @@ static int ocfs2_update_last_group_and_inode(handle_t *handle, OCFS2_FEATURE_COMPAT_BACKUP_SB)) { backups = ocfs2_calc_new_backup_super(bm_inode, group, - cl_cpg, 1); + cl_cpg, old_bg_clusters, 1); le16_add_cpu(&group->bg_free_bits_count, -1 * backups); } @@ -163,7 +172,7 @@ out_rollback: if (ret < 0) { ocfs2_calc_new_backup_super(bm_inode, group, - cl_cpg, 0); + cl_cpg, old_bg_clusters, 0); le16_add_cpu(&group->bg_free_bits_count, backups); le16_add_cpu(&group->bg_bits, -1 * num_bits); le16_add_cpu(&group->bg_free_bits_count, -1 * num_bits);