ext4: revert commit which was causing fs corruption after journal replays

Commit 007649375f ("ext4: initialize multi-block allocator before
checking block descriptors") causes the block group descriptor's count
of the number of free blocks to become inconsistent with the number of
free blocks in the allocation bitmap.  This is a harmless form of fs
corruption, but it causes the kernel to potentially remount the file
system read-only, or to panic, depending on the file systems's error
behavior.

Thanks to Eric Whitney for his tireless work to reproduce and to find
the guilty commit.

Fixes: 007649375f ("ext4: initialize multi-block allocator before checking block descriptors"

Cc: stable@vger.kernel.org  # 3.15
Reported-by: David Jander <david@protonic.nl>
Reported-by: Matteo Croce <technoboy85@gmail.com>
Tested-by: Eric Whitney <enwlinux@gmail.com>
Suggested-by: Eric Whitney <enwlinux@gmail.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Theodore Ts'o 2014-07-11 13:55:40 -04:00
Родитель 5dd214248f
Коммит f9ae9cf5d7
1 изменённых файлов: 24 добавлений и 27 удалений

Просмотреть файл

@ -3879,38 +3879,19 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
goto failed_mount2;
}
}
/*
* set up enough so that it can read an inode,
* and create new inode for buddy allocator
*/
sbi->s_gdb_count = db_count;
if (!test_opt(sb, NOLOAD) &&
EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
sb->s_op = &ext4_sops;
else
sb->s_op = &ext4_nojournal_sops;
ext4_ext_init(sb);
err = ext4_mb_init(sb);
if (err) {
ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
err);
goto failed_mount2;
}
if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
goto failed_mount2a;
goto failed_mount2;
}
if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
if (!ext4_fill_flex_info(sb)) {
ext4_msg(sb, KERN_ERR,
"unable to initialize "
"flex_bg meta info!");
goto failed_mount2a;
goto failed_mount2;
}
sbi->s_gdb_count = db_count;
get_random_bytes(&sbi->s_next_generation, sizeof(u32));
spin_lock_init(&sbi->s_next_gen_lock);
@ -3945,6 +3926,14 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
sbi->s_stripe = ext4_get_stripe_size(sbi);
sbi->s_extent_max_zeroout_kb = 32;
/*
* set up enough so that it can read an inode
*/
if (!test_opt(sb, NOLOAD) &&
EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
sb->s_op = &ext4_sops;
else
sb->s_op = &ext4_nojournal_sops;
sb->s_export_op = &ext4_export_ops;
sb->s_xattr = ext4_xattr_handlers;
#ifdef CONFIG_QUOTA
@ -4134,13 +4123,21 @@ no_journal:
if (err) {
ext4_msg(sb, KERN_ERR, "failed to reserve %llu clusters for "
"reserved pool", ext4_calculate_resv_clusters(sb));
goto failed_mount5;
goto failed_mount4a;
}
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);
err = ext4_mb_init(sb);
if (err) {
ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
err);
goto failed_mount5;
}
@ -4217,8 +4214,11 @@ failed_mount8:
failed_mount7:
ext4_unregister_li_request(sb);
failed_mount6:
ext4_release_system_zone(sb);
ext4_mb_release(sb);
failed_mount5:
ext4_ext_release(sb);
ext4_release_system_zone(sb);
failed_mount4a:
dput(sb->s_root);
sb->s_root = NULL;
failed_mount4:
@ -4242,14 +4242,11 @@ failed_mount3:
percpu_counter_destroy(&sbi->s_extent_cache_cnt);
if (sbi->s_mmp_tsk)
kthread_stop(sbi->s_mmp_tsk);
failed_mount2a:
ext4_mb_release(sb);
failed_mount2:
for (i = 0; i < db_count; i++)
brelse(sbi->s_group_desc[i]);
ext4_kvfree(sbi->s_group_desc);
failed_mount:
ext4_ext_release(sb);
if (sbi->s_chksum_driver)
crypto_free_shash(sbi->s_chksum_driver);
if (sbi->s_proc) {