From 7f6858a3b9361ca9ff89cc2b9cdc3cf3b9bee356 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Tue, 28 Jul 2020 15:04:37 +0200 Subject: [PATCH] ext4: correctly restore system zone info when remount fails [ Upstream commit 0f5bde1db174f6c471f0bd27198575719dabe3e5 ] When remounting filesystem fails late during remount handling and block_validity mount option is also changed during the remount, we fail to restore system zone information to a state matching the mount option. This is mostly harmless, just the block validity checking will not match the situation described by the mount option. Make sure these two are always consistent. Reported-by: Lukas Czerner Reviewed-by: Lukas Czerner Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20200728130437.7804-7-jack@suse.cz Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/ext4/block_validity.c | 8 -------- fs/ext4/super.c | 29 +++++++++++++++++++++-------- 2 files changed, 21 insertions(+), 16 deletions(-) diff --git a/fs/ext4/block_validity.c b/fs/ext4/block_validity.c index 552164034d34..f22a89cdb407 100644 --- a/fs/ext4/block_validity.c +++ b/fs/ext4/block_validity.c @@ -250,14 +250,6 @@ int ext4_setup_system_zone(struct super_block *sb) int flex_size = ext4_flex_bg_size(sbi); int ret; - if (!test_opt(sb, BLOCK_VALIDITY)) { - if (sbi->system_blks) - ext4_release_system_zone(sb); - return 0; - } - if (sbi->system_blks) - return 0; - system_blks = kzalloc(sizeof(*system_blks), GFP_KERNEL); if (!system_blks) return -ENOMEM; diff --git a/fs/ext4/super.c b/fs/ext4/super.c index daabd7a2cee8..9ac34b6ae073 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4473,11 +4473,13 @@ no_journal: ext4_set_resv_clusters(sb); - err = ext4_setup_system_zone(sb); - if (err) { - ext4_msg(sb, KERN_ERR, "failed to initialize system " - "zone (%d)", err); - goto failed_mount4a; + if (test_opt(sb, BLOCK_VALIDITY)) { + err = ext4_setup_system_zone(sb); + if (err) { + ext4_msg(sb, KERN_ERR, "failed to initialize system " + "zone (%d)", err); + goto failed_mount4a; + } } ext4_ext_init(sb); @@ -5470,9 +5472,16 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) ext4_register_li_request(sb, first_not_zeroed); } - err = ext4_setup_system_zone(sb); - if (err) - goto restore_opts; + /* + * Handle creation of system zone data early because it can fail. + * Releasing of existing data is done when we are sure remount will + * succeed. + */ + if (test_opt(sb, BLOCK_VALIDITY) && !sbi->system_blks) { + err = ext4_setup_system_zone(sb); + if (err) + goto restore_opts; + } if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) { err = ext4_commit_super(sb, 1); @@ -5494,6 +5503,8 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) } } #endif + if (!test_opt(sb, BLOCK_VALIDITY) && sbi->system_blks) + ext4_release_system_zone(sb); /* * Some options can be enabled by ext4 and/or by VFS mount flag @@ -5515,6 +5526,8 @@ restore_opts: sbi->s_commit_interval = old_opts.s_commit_interval; sbi->s_min_batch_time = old_opts.s_min_batch_time; sbi->s_max_batch_time = old_opts.s_max_batch_time; + if (!test_opt(sb, BLOCK_VALIDITY) && sbi->system_blks) + ext4_release_system_zone(sb); #ifdef CONFIG_QUOTA sbi->s_jquota_fmt = old_opts.s_jquota_fmt; for (i = 0; i < EXT4_MAXQUOTAS; i++) {