linux/fs/btrfs
Qu Wenruo 4dbd80fb91 btrfs: Fix metadata underflow caused by btrfs_reloc_clone_csum error
[BUG]
When btrfs_reloc_clone_csum() reports error, it can underflow metadata
and leads to kernel assertion on outstanding extents in
run_delalloc_nocow() and cow_file_range().

 BTRFS info (device vdb5): relocating block group 12582912 flags data
 BTRFS info (device vdb5): found 1 extents
 assertion failed: inode->outstanding_extents >= num_extents, file: fs/btrfs//extent-tree.c, line: 5858

Currently, due to another bug blocking ordered extents, the bug is only
reproducible under certain block group layout and using error injection.

a) Create one data block group with one 4K extent in it.
   To avoid the bug that hangs btrfs due to ordered extent which never
   finishes
b) Make btrfs_reloc_clone_csum() always fail
c) Relocate that block group

[CAUSE]
run_delalloc_nocow() and cow_file_range() handles error from
btrfs_reloc_clone_csum() wrongly:

(The ascii chart shows a more generic case of this bug other than the
bug mentioned above)

|<------------------ delalloc range --------------------------->|
| OE 1 | OE 2 | ... | OE n |
                    |<----------- cleanup range --------------->|
|<-----------  ----------->|
             \/
 btrfs_finish_ordered_io() range

So error handler, which calls extent_clear_unlock_delalloc() with
EXTENT_DELALLOC and EXTENT_DO_ACCOUNT bits, and btrfs_finish_ordered_io()
will both cover OE n, and free its metadata, causing metadata under flow.

[Fix]
The fix is to ensure after calling btrfs_add_ordered_extent(), we only
call error handler after increasing the iteration offset, so that
cleanup range won't cover any created ordered extent.

|<------------------ delalloc range --------------------------->|
| OE 1 | OE 2 | ... | OE n |
|<-----------  ----------->|<---------- cleanup range --------->|
             \/
 btrfs_finish_ordered_io() range

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Liu Bo <bo.li.liu@oracle.com>
2017-04-26 16:27:21 +01:00
..
tests btrfs: Make get_extent_t take btrfs_inode 2017-02-28 11:30:11 +01:00
acl.c posix_acl: Clear SGID bit when setting file permissions 2016-09-22 10:55:32 +02:00
async-thread.c btrfs: fix crash when tracepoint arguments are freed by wq callbacks 2017-01-09 11:24:50 +01:00
async-thread.h btrfs: limit async_work allocation and worker func duration 2016-12-13 11:01:30 -08:00
backref.c btrfs: remove unused parameter from __add_inline_refs 2017-02-17 12:03:54 +01:00
backref.h
btrfs_inode.h btrfs: make btrfs_inode_resume_unlocked_dio take btrfs_inode 2017-02-28 11:30:12 +01:00
check-integrity.c btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
check-integrity.h btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
compression.c btrfs: derive maximum output size in the compression implementation 2017-02-28 14:26:36 +01:00
compression.h btrfs: derive maximum output size in the compression implementation 2017-02-28 14:26:36 +01:00
ctree.c Merge branch 'for-chris-4.11-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.11 2017-02-28 14:35:09 -08:00
ctree.h btrfs: Change qgroup_meta_rsv to 64bit 2017-03-29 14:29:08 +02:00
dedupe.h btrfs: expand cow_file_range() to support in-band dedup and subpage-blocksize 2016-07-26 13:52:25 +02:00
delayed-inode.c btrfs: Make btrfs_i_size_write take btrfs_inode 2017-02-28 11:30:06 +01:00
delayed-inode.h btrfs: Make btrfs_inode_delayed_dir_index_count take btrfs_inode 2017-02-14 15:50:53 +01:00
delayed-ref.c btrfs: qgroup: Move half of the qgroup accounting time out of commit trans 2017-02-17 12:03:55 +01:00
delayed-ref.h Btrfs: pass delayed_refs directly to btrfs_find_delayed_ref_head 2017-02-14 15:50:59 +01:00
dev-replace.c btrfs: constify device path passed to relevant helpers 2017-02-28 14:26:07 +01:00
dev-replace.h btrfs: constify device path passed to relevant helpers 2017-02-28 14:26:07 +01:00
dir-item.c btrfs: do proper error handling in btrfs_insert_xattr_item 2017-02-28 14:27:11 +01:00
disk-io.c btrfs: Change qgroup_meta_rsv to 64bit 2017-03-29 14:29:08 +02:00
disk-io.h btrfs: constify input buffer of btrfs_csum_data 2017-02-28 14:26:07 +01:00
export.c btrfs: Make btrfs_ino take a struct btrfs_inode 2017-02-14 15:50:51 +01:00
export.h
extent_io.c Btrfs: bring back repair during read 2017-03-29 14:29:07 +02:00
extent_io.h btrfs: add dummy callback for readpage_io_failed and drop checks 2017-02-28 14:29:24 +01:00
extent_map.c btrfs: Fix slab accounting flags 2016-07-26 13:52:25 +02:00
extent_map.h btrfs: cleanup, stop casting for extent_map->lookup everywhere 2016-01-15 19:22:28 +01:00
extent-tree.c Merge branch 'for-chris-4.11-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.11 2017-02-28 14:35:09 -08:00
file-item.c Merge branch 'for-chris-4.11-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.11 2017-02-28 14:35:09 -08:00
file.c btrfs: Make get_extent_t take btrfs_inode 2017-02-28 11:30:11 +01:00
free-space-cache.c btrfs: all btrfs_delalloc_release_metadata take btrfs_inode 2017-02-28 11:30:07 +01:00
free-space-cache.h btrfs: free-space-cache, clean up unnecessary root arguments 2017-02-17 12:03:56 +01:00
free-space-tree.c btrfs: remove unused parameter from clean_tree_block 2017-02-17 12:03:51 +01:00
free-space-tree.h Btrfs: implement the free space B-tree 2015-12-17 12:16:47 -08:00
hash.c btrfs: advertise which crc32c implementation is being used at module load 2016-06-06 14:08:28 +02:00
hash.h btrfs: advertise which crc32c implementation is being used at module load 2016-06-06 14:08:28 +02:00
inode-item.c btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
inode-map.c btrfs: all btrfs_delalloc_release_metadata take btrfs_inode 2017-02-28 11:30:07 +01:00
inode-map.h Btrfs: Initialize btrfs_root->highest_objectid when loading tree root and subvolume roots 2016-01-15 19:25:02 +01:00
inode.c btrfs: Fix metadata underflow caused by btrfs_reloc_clone_csum error 2017-04-26 16:27:21 +01:00
ioctl.c btrfs: constify name of subvolume in creation helpers 2017-02-28 14:26:08 +01:00
Kconfig
locking.c btrfs: cleanup, remove stray return statements 2016-01-07 14:30:52 +01:00
locking.h
lzo.c btrfs: derive maximum output size in the compression implementation 2017-02-28 14:26:36 +01:00
Makefile Btrfs: add free space tree sanity tests 2015-12-17 12:16:47 -08:00
math.h
ordered-data.c btrfs: Make btrfs_lookup_ordered_range take btrfs_inode 2017-02-28 11:30:08 +01:00
ordered-data.h btrfs: Make btrfs_lookup_ordered_range take btrfs_inode 2017-02-28 11:30:08 +01:00
orphan.c
print-tree.c btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
print-tree.h btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
props.c btrfs: Make btrfs_ino take a struct btrfs_inode 2017-02-14 15:50:51 +01:00
props.h
qgroup.c btrfs: Change qgroup_meta_rsv to 64bit 2017-03-29 14:29:08 +02:00
qgroup.h btrfs: qgroup: Move half of the qgroup accounting time out of commit trans 2017-02-17 12:03:55 +01:00
raid56.c btrfs: raid56: Remove unused variable in lock_stripe_add 2017-02-14 15:50:59 +01:00
raid56.h btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
rcu-string.h
reada.c btrfs: take an fs_info directly when the root is not used otherwise 2016-12-06 16:06:59 +01:00
relocation.c btrfs: Make btrfs_orphan_add take btrfs_inode 2017-02-28 11:30:10 +01:00
root-tree.c Btrfs: constify struct btrfs_{,disk_}key wherever possible 2017-02-14 15:50:58 +01:00
scrub.c btrfs: Make check_extent_to_block take btrfs_inode 2017-02-28 11:30:11 +01:00
send.c Btrfs: fix an integer overflow check 2017-03-29 14:29:08 +02:00
send.h Btrfs: use linux/sizes.h to represent constants 2016-01-07 14:38:02 +01:00
struct-funcs.c btrfs: fix string and comment grammatical issues and typos 2016-05-25 22:35:14 +02:00
super.c btrfs: drop the nossd flag when remounting with -o ssd 2017-04-11 18:48:59 +02:00
sysfs.c btrfs: convert printk(KERN_* to use pr_* calls 2016-09-26 18:08:44 +02:00
sysfs.h btrfs: sysfs: introduce helper for syncing bits with sysfs files 2016-01-21 18:50:40 +01:00
transaction.c btrfs: Make btrfs_i_size_write take btrfs_inode 2017-02-28 11:30:06 +01:00
transaction.h btrfs: remove root parameter from transaction commit/end routines 2016-12-06 16:07:00 +01:00
tree-defrag.c Btrfs: fix locking bugs when defragging leaves 2015-12-18 02:51:32 +00:00
tree-log.c Merge branch 'for-chris-4.11-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux into for-linus-4.11 2017-02-28 14:35:09 -08:00
tree-log.h btrfs: Make btrfs_del_inode_ref take btrfs_inode 2017-02-14 15:50:54 +01:00
ulist.c btrfs: ulist: rename ulist_fini to ulist_release 2017-02-17 12:03:50 +01:00
ulist.h btrfs: ulist: rename ulist_fini to ulist_release 2017-02-17 12:03:50 +01:00
uuid-tree.c btrfs: return the actual error value from from btrfs_uuid_tree_iterate 2016-12-19 18:08:15 +01:00
volumes.c Btrfs: fix potential use-after-free for cloned bio 2017-04-11 18:49:56 +02:00
volumes.h btrfs: constify device path passed to relevant helpers 2017-02-28 14:26:07 +01:00
xattr.c btrfs: fix over-80 lines introduced by previous cleanups 2017-02-14 15:50:57 +01:00
xattr.h btrfs: Switch to generic xattr handlers 2016-05-17 19:17:09 -04:00
zlib.c btrfs: derive maximum output size in the compression implementation 2017-02-28 14:26:36 +01:00