[ Upstream commit fa91e4aa1716004ea8096d5185ec0451e206aea0 ]
[BUG]
When running tests like generic/013 on test device with btrfs quota
enabled, it can normally lead to data leak, detected at unmount time:
BTRFS warning (device dm-3): qgroup 0/5 has unreleased space, type 0 rsv 4096
------------[ cut here ]------------
WARNING: CPU: 11 PID: 16386 at fs/btrfs/disk-io.c:4142 close_ctree+0x1dc/0x323 [btrfs]
RIP: 0010:close_ctree+0x1dc/0x323 [btrfs]
Call Trace:
btrfs_put_super+0x15/0x17 [btrfs]
generic_shutdown_super+0x72/0x110
kill_anon_super+0x18/0x30
btrfs_kill_super+0x17/0x30 [btrfs]
deactivate_locked_super+0x3b/0xa0
deactivate_super+0x40/0x50
cleanup_mnt+0x135/0x190
__cleanup_mnt+0x12/0x20
task_work_run+0x64/0xb0
__prepare_exit_to_usermode+0x1bc/0x1c0
__syscall_return_slowpath+0x47/0x230
do_syscall_64+0x64/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
---[ end trace caf08beafeca2392 ]---
BTRFS error (device dm-3): qgroup reserved space leaked
[CAUSE]
In the offending case, the offending operations are:
2/6: writev f2X[269 1 0 0 0 0] [1006997,67,288] 0
2/7: truncate f2X[269 1 0 0 48 1026293] 18388 0
The following sequence of events could happen after the writev():
CPU1 (writeback) | CPU2 (truncate)
-----------------------------------------------------------------
btrfs_writepages() |
|- extent_write_cache_pages() |
|- Got page for 1003520 |
| 1003520 is Dirty, no writeback |
| So (!clear_page_dirty_for_io()) |
| gets called for it |
|- Now page 1003520 is Clean. |
| | btrfs_setattr()
| | |- btrfs_setsize()
| | |- truncate_setsize()
| | New i_size is 18388
|- __extent_writepage() |
| |- page_offset() > i_size |
|- btrfs_invalidatepage() |
|- Page is clean, so no qgroup |
callback executed
This means, the qgroup reserved data space is not properly released in
btrfs_invalidatepage() as the page is Clean.
[FIX]
Instead of checking the dirty bit of a page, call
btrfs_qgroup_free_data() unconditionally in btrfs_invalidatepage().
As qgroup rsv are completely bound to the QGROUP_RESERVED bit of
io_tree, not bound to page status, thus we won't cause double freeing
anyway.
Fixes: 0b34c261e2 ("btrfs: qgroup: Prevent qgroup->reserved from going subzero")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7c09c03091ac562ddca2b393e5d65c1d37da79f1 ]
Deleting a subvolume on a full filesystem leads to ENOSPC followed by a
forced read-only. This is not a transaction abort and the filesystem is
otherwise ok, so the error should be just propagated to the callers.
This is caused by unnecessary call to btrfs_handle_fs_error for all
errors, except EAGAIN. This does not make sense as the standard
transaction abort mechanism is in btrfs_drop_snapshot so all relevant
failures are handled.
Originally in commit cb1b69f450 ("Btrfs: forced readonly when
btrfs_drop_snapshot() fails") there was no return value at all, so the
btrfs_std_error made some sense but once the error handling and
propagation has been implemented we don't need it anymore.
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 1c78544eaa4660096aeb6a57ec82b42cdb3bfe5a upstream.
When faulting in the pages for the user supplied buffer for the search
ioctl, we are passing only the base address of the buffer to the function
fault_in_pages_writeable(). This means that after the first iteration of
the while loop that searches for leaves, when we have a non-zero offset,
stored in 'sk_offset', we try to fault in a wrong page range.
So fix this by adding the offset in 'sk_offset' to the base address of the
user supplied buffer when calling fault_in_pages_writeable().
Several users have reported that the applications compsize and bees have
started to operate incorrectly since commit a48b73eca4ceb9 ("btrfs: fix
potential deadlock in the search ioctl") was added to stable trees, and
these applications make heavy use of the search ioctls. This fixes their
issues.
Link: https://lore.kernel.org/linux-btrfs/632b888d-a3c3-b085-cdf5-f9bb61017d92@lechevalier.se/
Link: https://github.com/kilobyte/compsize/issues/34
Fixes: a48b73eca4ceb9 ("btrfs: fix potential deadlock in the search ioctl")
CC: stable@vger.kernel.org # 4.4+
Tested-by: A L <mail@lechevalier.se>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fccc0007b8dc952c6bc0805cdf842eb8ea06a639 upstream.
Nikolay reported a lockdep splat in generic/476 that I could reproduce
with btrfs/187.
======================================================
WARNING: possible circular locking dependency detected
5.9.0-rc2+ #1 Tainted: G W
------------------------------------------------------
kswapd0/100 is trying to acquire lock:
ffff9e8ef38b6268 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x3f/0x330
but task is already holding lock:
ffffffffa9d74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (fs_reclaim){+.+.}-{0:0}:
fs_reclaim_acquire+0x65/0x80
slab_pre_alloc_hook.constprop.0+0x20/0x200
kmem_cache_alloc_trace+0x3a/0x1a0
btrfs_alloc_device+0x43/0x210
add_missing_dev+0x20/0x90
read_one_chunk+0x301/0x430
btrfs_read_sys_array+0x17b/0x1b0
open_ctree+0xa62/0x1896
btrfs_mount_root.cold+0x12/0xea
legacy_get_tree+0x30/0x50
vfs_get_tree+0x28/0xc0
vfs_kern_mount.part.0+0x71/0xb0
btrfs_mount+0x10d/0x379
legacy_get_tree+0x30/0x50
vfs_get_tree+0x28/0xc0
path_mount+0x434/0xc00
__x64_sys_mount+0xe3/0x120
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #1 (&fs_info->chunk_mutex){+.+.}-{3:3}:
__mutex_lock+0x7e/0x7e0
btrfs_chunk_alloc+0x125/0x3a0
find_free_extent+0xdf6/0x1210
btrfs_reserve_extent+0xb3/0x1b0
btrfs_alloc_tree_block+0xb0/0x310
alloc_tree_block_no_bg_flush+0x4a/0x60
__btrfs_cow_block+0x11a/0x530
btrfs_cow_block+0x104/0x220
btrfs_search_slot+0x52e/0x9d0
btrfs_lookup_inode+0x2a/0x8f
__btrfs_update_delayed_inode+0x80/0x240
btrfs_commit_inode_delayed_inode+0x119/0x120
btrfs_evict_inode+0x357/0x500
evict+0xcf/0x1f0
vfs_rmdir.part.0+0x149/0x160
do_rmdir+0x136/0x1a0
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #0 (&delayed_node->mutex){+.+.}-{3:3}:
__lock_acquire+0x1184/0x1fa0
lock_acquire+0xa4/0x3d0
__mutex_lock+0x7e/0x7e0
__btrfs_release_delayed_node.part.0+0x3f/0x330
btrfs_evict_inode+0x24c/0x500
evict+0xcf/0x1f0
dispose_list+0x48/0x70
prune_icache_sb+0x44/0x50
super_cache_scan+0x161/0x1e0
do_shrink_slab+0x178/0x3c0
shrink_slab+0x17c/0x290
shrink_node+0x2b2/0x6d0
balance_pgdat+0x30a/0x670
kswapd+0x213/0x4c0
kthread+0x138/0x160
ret_from_fork+0x1f/0x30
other info that might help us debug this:
Chain exists of:
&delayed_node->mutex --> &fs_info->chunk_mutex --> fs_reclaim
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(fs_reclaim);
lock(&fs_info->chunk_mutex);
lock(fs_reclaim);
lock(&delayed_node->mutex);
*** DEADLOCK ***
3 locks held by kswapd0/100:
#0: ffffffffa9d74700 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x5/0x30
#1: ffffffffa9d65c50 (shrinker_rwsem){++++}-{3:3}, at: shrink_slab+0x115/0x290
#2: ffff9e8e9da260e0 (&type->s_umount_key#48){++++}-{3:3}, at: super_cache_scan+0x38/0x1e0
stack backtrace:
CPU: 1 PID: 100 Comm: kswapd0 Tainted: G W 5.9.0-rc2+ #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
Call Trace:
dump_stack+0x92/0xc8
check_noncircular+0x12d/0x150
__lock_acquire+0x1184/0x1fa0
lock_acquire+0xa4/0x3d0
? __btrfs_release_delayed_node.part.0+0x3f/0x330
__mutex_lock+0x7e/0x7e0
? __btrfs_release_delayed_node.part.0+0x3f/0x330
? __btrfs_release_delayed_node.part.0+0x3f/0x330
? lock_acquire+0xa4/0x3d0
? btrfs_evict_inode+0x11e/0x500
? find_held_lock+0x2b/0x80
__btrfs_release_delayed_node.part.0+0x3f/0x330
btrfs_evict_inode+0x24c/0x500
evict+0xcf/0x1f0
dispose_list+0x48/0x70
prune_icache_sb+0x44/0x50
super_cache_scan+0x161/0x1e0
do_shrink_slab+0x178/0x3c0
shrink_slab+0x17c/0x290
shrink_node+0x2b2/0x6d0
balance_pgdat+0x30a/0x670
kswapd+0x213/0x4c0
? _raw_spin_unlock_irqrestore+0x46/0x60
? add_wait_queue_exclusive+0x70/0x70
? balance_pgdat+0x670/0x670
kthread+0x138/0x160
? kthread_create_worker_on_cpu+0x40/0x40
ret_from_fork+0x1f/0x30
This is because we are holding the chunk_mutex when we call
btrfs_alloc_device, which does a GFP_KERNEL allocation. We don't want
to switch that to a GFP_NOFS lock because this is the only place where
it matters. So instead use memalloc_nofs_save() around the allocation
in order to avoid the lockdep splat.
Reported-by: Nikolay Borisov <nborisov@suse.com>
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ea57788eb76dc81f6003245427356a1dcd0ac524 upstream.
[BUG]
A completely sane converted fs will cause kernel warning at balance
time:
[ 1557.188633] BTRFS info (device sda7): relocating block group 8162107392 flags data
[ 1563.358078] BTRFS info (device sda7): found 11722 extents
[ 1563.358277] BTRFS info (device sda7): leaf 7989321728 gen 95 total ptrs 213 free space 3458 owner 2
[ 1563.358280] item 0 key (7984947200 169 0) itemoff 16250 itemsize 33
[ 1563.358281] extent refs 1 gen 90 flags 2
[ 1563.358282] ref#0: tree block backref root 4
[ 1563.358285] item 1 key (7985602560 169 0) itemoff 16217 itemsize 33
[ 1563.358286] extent refs 1 gen 93 flags 258
[ 1563.358287] ref#0: shared block backref parent 7985602560
[ 1563.358288] (parent 7985602560 is NOT ALIGNED to nodesize 16384)
[ 1563.358290] item 2 key (7985635328 169 0) itemoff 16184 itemsize 33
...
[ 1563.358995] BTRFS error (device sda7): eb 7989321728 invalid extent inline ref type 182
[ 1563.358996] ------------[ cut here ]------------
[ 1563.359005] WARNING: CPU: 14 PID: 2930 at 0xffffffff9f231766
Then with transaction abort, and obviously failed to balance the fs.
[CAUSE]
That mentioned inline ref type 182 is completely sane, it's
BTRFS_SHARED_BLOCK_REF_KEY, it's some extra check making kernel to
believe it's invalid.
Commit 64ecdb647d ("Btrfs: add one more sanity check for shared ref
type") introduced extra checks for backref type.
One of the requirement is, parent bytenr must be aligned to node size,
which is not correct.
One example is like this:
0 1G 1G+4K 2G 2G+4K
| |///////////////////|//| <- A chunk starts at 1G+4K
| | <- A tree block get reserved at bytenr 1G+4K
Then we have a valid tree block at bytenr 1G+4K, but not aligned to
nodesize (16K).
Such chunk is not ideal, but current kernel can handle it pretty well.
We may warn about such tree block in the future, but should not reject
them.
[FIX]
Change the alignment requirement from node size alignment to sector size
alignment.
Also, to make our lives a little easier, also output @iref when
btrfs_get_extent_inline_ref_type() failed, so we can locate the item
easier.
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=205475
Fixes: 64ecdb647d ("Btrfs: add one more sanity check for shared ref type")
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
[ update comments and messages ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a48b73eca4ceb9b8a4b97f290a065335dbcd8a04 ]
With the conversion of the tree locks to rwsem I got the following
lockdep splat:
======================================================
WARNING: possible circular locking dependency detected
5.8.0-rc7-00165-g04ec4da5f45f-dirty #922 Not tainted
------------------------------------------------------
compsize/11122 is trying to acquire lock:
ffff889fabca8768 (&mm->mmap_lock#2){++++}-{3:3}, at: __might_fault+0x3e/0x90
but task is already holding lock:
ffff889fe720fe40 (btrfs-fs-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x39/0x180
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (btrfs-fs-00){++++}-{3:3}:
down_write_nested+0x3b/0x70
__btrfs_tree_lock+0x24/0x120
btrfs_search_slot+0x756/0x990
btrfs_lookup_inode+0x3a/0xb4
__btrfs_update_delayed_inode+0x93/0x270
btrfs_async_run_delayed_root+0x168/0x230
btrfs_work_helper+0xd4/0x570
process_one_work+0x2ad/0x5f0
worker_thread+0x3a/0x3d0
kthread+0x133/0x150
ret_from_fork+0x1f/0x30
-> #1 (&delayed_node->mutex){+.+.}-{3:3}:
__mutex_lock+0x9f/0x930
btrfs_delayed_update_inode+0x50/0x440
btrfs_update_inode+0x8a/0xf0
btrfs_dirty_inode+0x5b/0xd0
touch_atime+0xa1/0xd0
btrfs_file_mmap+0x3f/0x60
mmap_region+0x3a4/0x640
do_mmap+0x376/0x580
vm_mmap_pgoff+0xd5/0x120
ksys_mmap_pgoff+0x193/0x230
do_syscall_64+0x50/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #0 (&mm->mmap_lock#2){++++}-{3:3}:
__lock_acquire+0x1272/0x2310
lock_acquire+0x9e/0x360
__might_fault+0x68/0x90
_copy_to_user+0x1e/0x80
copy_to_sk.isra.32+0x121/0x300
search_ioctl+0x106/0x200
btrfs_ioctl_tree_search_v2+0x7b/0xf0
btrfs_ioctl+0x106f/0x30a0
ksys_ioctl+0x83/0xc0
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x50/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xa9
other info that might help us debug this:
Chain exists of:
&mm->mmap_lock#2 --> &delayed_node->mutex --> btrfs-fs-00
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(btrfs-fs-00);
lock(&delayed_node->mutex);
lock(btrfs-fs-00);
lock(&mm->mmap_lock#2);
*** DEADLOCK ***
1 lock held by compsize/11122:
#0: ffff889fe720fe40 (btrfs-fs-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x39/0x180
stack backtrace:
CPU: 17 PID: 11122 Comm: compsize Kdump: loaded Not tainted 5.8.0-rc7-00165-g04ec4da5f45f-dirty #922
Hardware name: Quanta Tioga Pass Single Side 01-0030993006/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018
Call Trace:
dump_stack+0x78/0xa0
check_noncircular+0x165/0x180
__lock_acquire+0x1272/0x2310
lock_acquire+0x9e/0x360
? __might_fault+0x3e/0x90
? find_held_lock+0x72/0x90
__might_fault+0x68/0x90
? __might_fault+0x3e/0x90
_copy_to_user+0x1e/0x80
copy_to_sk.isra.32+0x121/0x300
? btrfs_search_forward+0x2a6/0x360
search_ioctl+0x106/0x200
btrfs_ioctl_tree_search_v2+0x7b/0xf0
btrfs_ioctl+0x106f/0x30a0
? __do_sys_newfstat+0x5a/0x70
? ksys_ioctl+0x83/0xc0
ksys_ioctl+0x83/0xc0
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x50/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xa9
The problem is we're doing a copy_to_user() while holding tree locks,
which can deadlock if we have to do a page fault for the copy_to_user().
This exists even without my locking changes, so it needs to be fixed.
Rework the search ioctl to do the pre-fault and then
copy_to_user_nofault for the copying.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit d3beaa253fd6fa40b8b18a216398e6e5376a9d21 ]
These are special extent buffers that get rewound in order to lookup
the state of the tree at a specific point in time. As such they do not
go through the normal initialization paths that set their lockdep class,
so handle them appropriately when they are created and before they are
locked.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 24cee18a1c1d7c731ea5987e0c99daea22ae7f4a ]
When a rewound buffer is created it already has a ref count of 1 and the
dummy flag set. Then another ref is taken bumping the count to 2.
Finally when this buffer is released from btrfs_release_path the extra
reference is decremented by the special handling code in
free_extent_buffer.
However, this special code is in fact redundant sinca ref count of 1 is
still correct since the buffer is only accessed via btrfs_path struct.
This paves the way forward of removing the special handling in
free_extent_buffer.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6c122e2a0c515cfb3f3a9cefb5dad4cb62109c78 ]
get_old_root used used only by btrfs_search_old_slot to initialise the
path structure. The old root is always a cloned buffer (either via alloc
dummy or via btrfs_clone_extent_buffer) and its reference count is 2: 1
from allocation, 1 from extent_buffer_get call in get_old_root.
This latter explicit ref count acquire operation is in fact unnecessary
since the semantic is such that the newly allocated buffer is handed
over to the btrfs_path for lifetime management. Considering this just
remove the extra extent_buffer_get in get_old_root.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 9771a5cf937129307d9f58922d60484d58ababe7 upstream.
With the conversion of the tree locks to rwsem I got the following
lockdep splat:
======================================================
WARNING: possible circular locking dependency detected
5.8.0-rc7-00167-g0d7ba0c5b375-dirty #925 Not tainted
------------------------------------------------------
btrfs-uuid/7955 is trying to acquire lock:
ffff88bfbafec0f8 (btrfs-root-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x39/0x180
but task is already holding lock:
ffff88bfbafef2a8 (btrfs-uuid-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x39/0x180
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (btrfs-uuid-00){++++}-{3:3}:
down_read_nested+0x3e/0x140
__btrfs_tree_read_lock+0x39/0x180
__btrfs_read_lock_root_node+0x3a/0x50
btrfs_search_slot+0x4bd/0x990
btrfs_uuid_tree_add+0x89/0x2d0
btrfs_uuid_scan_kthread+0x330/0x390
kthread+0x133/0x150
ret_from_fork+0x1f/0x30
-> #0 (btrfs-root-00){++++}-{3:3}:
__lock_acquire+0x1272/0x2310
lock_acquire+0x9e/0x360
down_read_nested+0x3e/0x140
__btrfs_tree_read_lock+0x39/0x180
__btrfs_read_lock_root_node+0x3a/0x50
btrfs_search_slot+0x4bd/0x990
btrfs_find_root+0x45/0x1b0
btrfs_read_tree_root+0x61/0x100
btrfs_get_root_ref.part.50+0x143/0x630
btrfs_uuid_tree_iterate+0x207/0x314
btrfs_uuid_rescan_kthread+0x12/0x50
kthread+0x133/0x150
ret_from_fork+0x1f/0x30
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(btrfs-uuid-00);
lock(btrfs-root-00);
lock(btrfs-uuid-00);
lock(btrfs-root-00);
*** DEADLOCK ***
1 lock held by btrfs-uuid/7955:
#0: ffff88bfbafef2a8 (btrfs-uuid-00){++++}-{3:3}, at: __btrfs_tree_read_lock+0x39/0x180
stack backtrace:
CPU: 73 PID: 7955 Comm: btrfs-uuid Kdump: loaded Not tainted 5.8.0-rc7-00167-g0d7ba0c5b375-dirty #925
Hardware name: Quanta Tioga Pass Single Side 01-0030993006/Tioga Pass Single Side, BIOS F08_3A18 12/20/2018
Call Trace:
dump_stack+0x78/0xa0
check_noncircular+0x165/0x180
__lock_acquire+0x1272/0x2310
lock_acquire+0x9e/0x360
? __btrfs_tree_read_lock+0x39/0x180
? btrfs_root_node+0x1c/0x1d0
down_read_nested+0x3e/0x140
? __btrfs_tree_read_lock+0x39/0x180
__btrfs_tree_read_lock+0x39/0x180
__btrfs_read_lock_root_node+0x3a/0x50
btrfs_search_slot+0x4bd/0x990
btrfs_find_root+0x45/0x1b0
btrfs_read_tree_root+0x61/0x100
btrfs_get_root_ref.part.50+0x143/0x630
btrfs_uuid_tree_iterate+0x207/0x314
? btree_readpage+0x20/0x20
btrfs_uuid_rescan_kthread+0x12/0x50
kthread+0x133/0x150
? kthread_create_on_node+0x60/0x60
ret_from_fork+0x1f/0x30
This problem exists because we have two different rescan threads,
btrfs_uuid_scan_kthread which creates the uuid tree, and
btrfs_uuid_tree_iterate that goes through and updates or deletes any out
of date roots. The problem is they both do things in different order.
btrfs_uuid_scan_kthread() reads the tree_root, and then inserts entries
into the uuid_root. btrfs_uuid_tree_iterate() scans the uuid_root, but
then does a btrfs_get_fs_root() which can read from the tree_root.
It's actually easy enough to not be holding the path in
btrfs_uuid_scan_kthread() when we add a uuid entry, as we already drop
it further down and re-start the search when we loop. So simply move
the path release before we add our entry to the uuid tree.
This also fixes a problem where we're holding a path open after we do
btrfs_end_transaction(), which has it's own problems.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit fb2fecbad50964b9f27a3b182e74e437b40753ef ]
With my new locking code dbench is so much faster that I tripped over a
transaction abort from ENOSPC. This turned out to be because
btrfs_del_dir_entries_in_log was checking for ret == -ENOSPC, but this
function sets err on error, and returns err. So instead of properly
marking the inode as needing a full commit, we were returning -ENOSPC
and aborting in __btrfs_unlink_inode. Fix this by checking the proper
variable so that we return the correct thing in the case of ENOSPC.
The ENOENT needs to be checked, because btrfs_lookup_dir_item_index()
can return -ENOENT if the dir item isn't in the tree log (which would
happen if we hadn't fsync'ed this guy). We actually handle that case in
__btrfs_unlink_inode, so it's an expected error to get back.
Fixes: 4a500fd178 ("Btrfs: Metadata ENOSPC handling for tree log")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add note and comment about ENOENT ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit bbc37d6e475eee8ffa2156ec813efc6bbb43c06d upstream.
If a transaction aborts it can cause a memory leak of the pages array of
a block group's io_ctl structure. The following steps explain how that can
happen:
1) Transaction N is committing, currently in state TRANS_STATE_UNBLOCKED
and it's about to start writing out dirty extent buffers;
2) Transaction N + 1 already started and another task, task A, just called
btrfs_commit_transaction() on it;
3) Block group B was dirtied (extents allocated from it) by transaction
N + 1, so when task A calls btrfs_start_dirty_block_groups(), at the
very beginning of the transaction commit, it starts writeback for the
block group's space cache by calling btrfs_write_out_cache(), which
allocates the pages array for the block group's io_ctl with a call to
io_ctl_init(). Block group A is added to the io_list of transaction
N + 1 by btrfs_start_dirty_block_groups();
4) While transaction N's commit is writing out the extent buffers, it gets
an IO error and aborts transaction N, also setting the file system to
RO mode;
5) Task A has already returned from btrfs_start_dirty_block_groups(), is at
btrfs_commit_transaction() and has set transaction N + 1 state to
TRANS_STATE_COMMIT_START. Immediately after that it checks that the
filesystem was turned to RO mode, due to transaction N's abort, and
jumps to the "cleanup_transaction" label. After that we end up at
btrfs_cleanup_one_transaction() which calls btrfs_cleanup_dirty_bgs().
That helper finds block group B in the transaction's io_list but it
never releases the pages array of the block group's io_ctl, resulting in
a memory leak.
In fact at the point when we are at btrfs_cleanup_dirty_bgs(), the pages
array points to pages that were already released by us at
__btrfs_write_out_cache() through the call to io_ctl_drop_pages(). We end
up freeing the pages array only after waiting for the ordered extent to
complete through btrfs_wait_cache_io(), which calls io_ctl_free() to do
that. But in the transaction abort case we don't wait for the space cache's
ordered extent to complete through a call to btrfs_wait_cache_io(), so
that's why we end up with a memory leak - we wait for the ordered extent
to complete indirectly by shutting down the work queues and waiting for
any jobs in them to complete before returning from close_ctree().
We can solve the leak simply by freeing the pages array right after
releasing the pages (with the call to io_ctl_drop_pages()) at
__btrfs_write_out_cache(), since we will never use it anymore after that
and the pages array points to already released pages at that point, which
is currently not a problem since no one will use it after that, but not a
good practice anyway since it can easily lead to use-after-free issues.
So fix this by freeing the pages array right after releasing the pages at
__btrfs_write_out_cache().
This issue can often be reproduced with test case generic/475 from fstests
and kmemleak can detect it and reports it with the following trace:
unreferenced object 0xffff9bbf009fa600 (size 512):
comm "fsstress", pid 38807, jiffies 4298504428 (age 22.028s)
hex dump (first 32 bytes):
00 a0 7c 4d 3d ed ff ff 40 a0 7c 4d 3d ed ff ff ..|M=...@.|M=...
80 a0 7c 4d 3d ed ff ff c0 a0 7c 4d 3d ed ff ff ..|M=.....|M=...
backtrace:
[<00000000f4b5cfe2>] __kmalloc+0x1a8/0x3e0
[<0000000028665e7f>] io_ctl_init+0xa7/0x120 [btrfs]
[<00000000a1f95b2d>] __btrfs_write_out_cache+0x86/0x4a0 [btrfs]
[<00000000207ea1b0>] btrfs_write_out_cache+0x7f/0xf0 [btrfs]
[<00000000af21f534>] btrfs_start_dirty_block_groups+0x27b/0x580 [btrfs]
[<00000000c3c23d44>] btrfs_commit_transaction+0xa6f/0xe70 [btrfs]
[<000000009588930c>] create_subvol+0x581/0x9a0 [btrfs]
[<000000009ef2fd7f>] btrfs_mksubvol+0x3fb/0x4a0 [btrfs]
[<00000000474e5187>] __btrfs_ioctl_snap_create+0x119/0x1a0 [btrfs]
[<00000000708ee349>] btrfs_ioctl_snap_create_v2+0xb0/0xf0 [btrfs]
[<00000000ea60106f>] btrfs_ioctl+0x12c/0x3130 [btrfs]
[<000000005c923d6d>] __x64_sys_ioctl+0x83/0xb0
[<0000000043ace2c9>] do_syscall_64+0x33/0x80
[<00000000904efbce>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
CC: stable@vger.kernel.org # 4.9+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 282dd7d7718444679b046b769d872b188818ca35 upstream.
Currently a user can set mount "-o compress" which will set the
compression algorithm to zlib, and use the default compress level for
zlib (3):
relatime,compress=zlib:3,space_cache
If the user remounts the fs using "-o compress=lzo", then the old
compress_level is used:
relatime,compress=lzo:3,space_cache
But lzo does not expose any tunable compression level. The same happens
if we set any compress argument with different level, also with zstd.
Fix this by resetting the compress_level when compress=lzo is
specified. With the fix applied, lzo is shown without compress level:
relatime,compress=lzo,space_cache
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a7f8b1c2ac21bf081b41264c9cfd6260dffa6246 ]
The incoming qgroup reserved space timing will move the data reservation
to ordered extent completely.
However in btrfs_punch_hole_lock_range() will call
btrfs_invalidate_page(), which will clear QGROUP_RESERVED bit for the
range.
In current stage it's OK, but if we're making ordered extents handle the
reserved space, then btrfs_punch_hole_lock_range() can clear the
QGROUP_RESERVED bit before we submit ordered extent, leading to qgroup
reserved space leakage.
So here change the timing to make reserve data space after
btrfs_punch_hole_lock_range().
The new timing is fine for either current code or the new code.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 1e6e238c3002ea3611465ce5f32777ddd6a40126 ]
[BUG]
There is a bug report of NULL pointer dereference caused in
compress_file_extent():
Oops: Kernel access of bad area, sig: 11 [#1]
LE PAGE_SIZE=64K MMU=Hash SMP NR_CPUS=2048 NUMA pSeries
Workqueue: btrfs-delalloc btrfs_delalloc_helper [btrfs]
NIP [c008000006dd4d34] compress_file_range.constprop.41+0x75c/0x8a0 [btrfs]
LR [c008000006dd4d1c] compress_file_range.constprop.41+0x744/0x8a0 [btrfs]
Call Trace:
[c000000c69093b00] [c008000006dd4d1c] compress_file_range.constprop.41+0x744/0x8a0 [btrfs] (unreliable)
[c000000c69093bd0] [c008000006dd4ebc] async_cow_start+0x44/0xa0 [btrfs]
[c000000c69093c10] [c008000006e14824] normal_work_helper+0xdc/0x598 [btrfs]
[c000000c69093c80] [c0000000001608c0] process_one_work+0x2c0/0x5b0
[c000000c69093d10] [c000000000160c38] worker_thread+0x88/0x660
[c000000c69093db0] [c00000000016b55c] kthread+0x1ac/0x1c0
[c000000c69093e20] [c00000000000b660] ret_from_kernel_thread+0x5c/0x7c
---[ end trace f16954aa20d822f6 ]---
[CAUSE]
For the following execution route of compress_file_range(), it's
possible to hit NULL pointer dereference:
compress_file_extent()
|- pages = NULL;
|- start = async_chunk->start = 0;
|- end = async_chunk = 4095;
|- nr_pages = 1;
|- inode_need_compress() == false; <<< Possible, see later explanation
| Now, we have nr_pages = 1, pages = NULL
|- cont:
|- ret = cow_file_range_inline();
|- if (ret <= 0) {
|- for (i = 0; i < nr_pages; i++) {
|- WARN_ON(pages[i]->mapping); <<< Crash
To enter above call execution branch, we need the following race:
Thread 1 (chattr) | Thread 2 (writeback)
--------------------------+------------------------------
| btrfs_run_delalloc_range
| |- inode_need_compress = true
| |- cow_file_range_async()
btrfs_ioctl_set_flag() |
|- binode_flags |= |
BTRFS_INODE_NOCOMPRESS |
| compress_file_range()
| |- inode_need_compress = false
| |- nr_page = 1 while pages = NULL
| | Then hit the crash
[FIX]
This patch will fix it by checking @pages before doing accessing it.
This patch is only designed as a hot fix and easy to backport.
More elegant fix may make btrfs only check inode_need_compress() once to
avoid such race, but that would be another story.
Reported-by: Luciano Chavez <chavez@us.ibm.com>
Fixes: 4d3a800ebb ("btrfs: merge nr_pages input and output parameter in compress_pages")
CC: stable@vger.kernel.org # 4.14.x: cecc8d9038d16: btrfs: Move free_pages_out label in inline extent handling branch in compress_file_range
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit cecc8d9038d164eda61fbcd72520975a554ea63e ]
This label is only executed if compress_file_range fails to create an
inline extent. So move its code in the semantically related inline
extent handling branch. No functional changes.
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3ef3959b29c4a5bd65526ab310a1a18ae533172a ]
Chris Murphy reported a problem where rpm ostree will bind mount a bunch
of things for whatever voodoo it's doing. But when it does this
/proc/mounts shows something like
/dev/sda /mnt/test btrfs rw,relatime,subvolid=256,subvol=/foo 0 0
/dev/sda /mnt/test/baz btrfs rw,relatime,subvolid=256,subvol=/foo/bar 0 0
Despite subvolid=256 being subvol=/foo. This is because we're just
spitting out the dentry of the mount point, which in the case of bind
mounts is the source path for the mountpoint. Instead we should spit
out the path to the actual subvol. Fix this by looking up the name for
the subvolid we have mounted. With this fix the same test looks like
this
/dev/sda /mnt/test btrfs rw,relatime,subvolid=256,subvol=/foo 0 0
/dev/sda /mnt/test/baz btrfs rw,relatime,subvolid=256,subvol=/foo 0 0
Reported-by: Chris Murphy <chris@colorremedies.com>
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit c0c907a47dccf2cf26251a8fb4a8e7a3bf79ce84 ]
The functions will be used outside of export.c and super.c to allow
resolving subvolume name from a given id, eg. for subvolume deletion by
id ioctl.
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ split from the next patch ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 4f26433e9b3eb7a55ed70d8f882ae9cd48ba448b upstream.
While logging an inode, at copy_items(), if we fail to lookup the checksums
for an extent we release the destination path, free the ins_data array and
then return immediately. However a previous iteration of the for loop may
have added checksums to the ordered_sums list, in which case we leak the
memory used by them.
So fix this by making sure we iterate the ordered_sums list and free all
its checksums before returning.
Fixes: 3650860b90 ("Btrfs: remove almost all of the BUG()'s from tree-log.c")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit bf53d4687b8f3f6b752f091eb85f62369a515dfd upstream.
In try_to_merge_free_space we attempt to find entries to the left and
right of the entry we are adding to see if they can be merged. We
search for an entry past our current info (saved into right_info), and
then if right_info exists and it has a rb_prev() we save the rb_prev()
into left_info.
However there's a slight problem in the case that we have a right_info,
but no entry previous to that entry. At that point we will search for
an entry just before the info we're attempting to insert. This will
simply find right_info again, and assign it to left_info, making them
both the same pointer.
Now if right_info _can_ be merged with the range we're inserting, we'll
add it to the info and free right_info. However further down we'll
access left_info, which was right_info, and thus get a use-after-free.
Fix this by only searching for the left entry if we don't find a right
entry at all.
The CVE referenced had a specially crafted file system that could
trigger this use-after-free. However with the tree checker improvements
we no longer trigger the conditions for the UAF. But the original
conditions still apply, hence this fix.
Reference: CVE-2019-19448
Fixes: 9630308170 ("Btrfs: use hybrid extents+bitmap rb tree for free space")
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 27942c9971cc405c60432eca9395e514a2ae9f5e upstream.
Reported by Forza on IRC that remounting with compression options does
not reflect the change in level, or at least it does not appear to do so
according to the messages:
mount -o compress=zstd:1 /dev/sda /mnt
mount -o remount,compress=zstd:15 /mnt
does not print the change to the level to syslog:
[ 41.366060] BTRFS info (device vda): use zstd compression, level 1
[ 41.368254] BTRFS info (device vda): disk space caching is enabled
[ 41.390429] BTRFS info (device vda): disk space caching is enabled
What really happens is that the message is lost but the level is actualy
changed.
There's another weird output, if compression is reset to 'no':
[ 45.413776] BTRFS info (device vda): use no compression, level 4
To fix that, save the previous compression level and print the message
in that case too and use separate message for 'no' compression.
CC: stable@vger.kernel.org # 4.19+
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 18c850fdc5a801bad4977b0f1723761d42267e45 upstream.
There's long existed a lockdep splat because we open our bdev's under
the ->device_list_mutex at mount time, which acquires the bd_mutex.
Usually this goes unnoticed, but if you do loopback devices at all
suddenly the bd_mutex comes with a whole host of other dependencies,
which results in the splat when you mount a btrfs file system.
======================================================
WARNING: possible circular locking dependency detected
5.8.0-0.rc3.1.fc33.x86_64+debug #1 Not tainted
------------------------------------------------------
systemd-journal/509 is trying to acquire lock:
ffff970831f84db0 (&fs_info->reloc_mutex){+.+.}-{3:3}, at: btrfs_record_root_in_trans+0x44/0x70 [btrfs]
but task is already holding lock:
ffff97083144d598 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x59/0x560 [btrfs]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #6 (sb_pagefaults){.+.+}-{0:0}:
__sb_start_write+0x13e/0x220
btrfs_page_mkwrite+0x59/0x560 [btrfs]
do_page_mkwrite+0x4f/0x130
do_wp_page+0x3b0/0x4f0
handle_mm_fault+0xf47/0x1850
do_user_addr_fault+0x1fc/0x4b0
exc_page_fault+0x88/0x300
asm_exc_page_fault+0x1e/0x30
-> #5 (&mm->mmap_lock#2){++++}-{3:3}:
__might_fault+0x60/0x80
_copy_from_user+0x20/0xb0
get_sg_io_hdr+0x9a/0xb0
scsi_cmd_ioctl+0x1ea/0x2f0
cdrom_ioctl+0x3c/0x12b4
sr_block_ioctl+0xa4/0xd0
block_ioctl+0x3f/0x50
ksys_ioctl+0x82/0xc0
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x52/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #4 (&cd->lock){+.+.}-{3:3}:
__mutex_lock+0x7b/0x820
sr_block_open+0xa2/0x180
__blkdev_get+0xdd/0x550
blkdev_get+0x38/0x150
do_dentry_open+0x16b/0x3e0
path_openat+0x3c9/0xa00
do_filp_open+0x75/0x100
do_sys_openat2+0x8a/0x140
__x64_sys_openat+0x46/0x70
do_syscall_64+0x52/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #3 (&bdev->bd_mutex){+.+.}-{3:3}:
__mutex_lock+0x7b/0x820
__blkdev_get+0x6a/0x550
blkdev_get+0x85/0x150
blkdev_get_by_path+0x2c/0x70
btrfs_get_bdev_and_sb+0x1b/0xb0 [btrfs]
open_fs_devices+0x88/0x240 [btrfs]
btrfs_open_devices+0x92/0xa0 [btrfs]
btrfs_mount_root+0x250/0x490 [btrfs]
legacy_get_tree+0x30/0x50
vfs_get_tree+0x28/0xc0
vfs_kern_mount.part.0+0x71/0xb0
btrfs_mount+0x119/0x380 [btrfs]
legacy_get_tree+0x30/0x50
vfs_get_tree+0x28/0xc0
do_mount+0x8c6/0xca0
__x64_sys_mount+0x8e/0xd0
do_syscall_64+0x52/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #2 (&fs_devs->device_list_mutex){+.+.}-{3:3}:
__mutex_lock+0x7b/0x820
btrfs_run_dev_stats+0x36/0x420 [btrfs]
commit_cowonly_roots+0x91/0x2d0 [btrfs]
btrfs_commit_transaction+0x4e6/0x9f0 [btrfs]
btrfs_sync_file+0x38a/0x480 [btrfs]
__x64_sys_fdatasync+0x47/0x80
do_syscall_64+0x52/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #1 (&fs_info->tree_log_mutex){+.+.}-{3:3}:
__mutex_lock+0x7b/0x820
btrfs_commit_transaction+0x48e/0x9f0 [btrfs]
btrfs_sync_file+0x38a/0x480 [btrfs]
__x64_sys_fdatasync+0x47/0x80
do_syscall_64+0x52/0xb0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
-> #0 (&fs_info->reloc_mutex){+.+.}-{3:3}:
__lock_acquire+0x1241/0x20c0
lock_acquire+0xb0/0x400
__mutex_lock+0x7b/0x820
btrfs_record_root_in_trans+0x44/0x70 [btrfs]
start_transaction+0xd2/0x500 [btrfs]
btrfs_dirty_inode+0x44/0xd0 [btrfs]
file_update_time+0xc6/0x120
btrfs_page_mkwrite+0xda/0x560 [btrfs]
do_page_mkwrite+0x4f/0x130
do_wp_page+0x3b0/0x4f0
handle_mm_fault+0xf47/0x1850
do_user_addr_fault+0x1fc/0x4b0
exc_page_fault+0x88/0x300
asm_exc_page_fault+0x1e/0x30
other info that might help us debug this:
Chain exists of:
&fs_info->reloc_mutex --> &mm->mmap_lock#2 --> sb_pagefaults
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(sb_pagefaults);
lock(&mm->mmap_lock#2);
lock(sb_pagefaults);
lock(&fs_info->reloc_mutex);
*** DEADLOCK ***
3 locks held by systemd-journal/509:
#0: ffff97083bdec8b8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x12e/0x4b0
#1: ffff97083144d598 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x59/0x560 [btrfs]
#2: ffff97083144d6a8 (sb_internal){.+.+}-{0:0}, at: start_transaction+0x3f8/0x500 [btrfs]
stack backtrace:
CPU: 0 PID: 509 Comm: systemd-journal Not tainted 5.8.0-0.rc3.1.fc33.x86_64+debug #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
dump_stack+0x92/0xc8
check_noncircular+0x134/0x150
__lock_acquire+0x1241/0x20c0
lock_acquire+0xb0/0x400
? btrfs_record_root_in_trans+0x44/0x70 [btrfs]
? lock_acquire+0xb0/0x400
? btrfs_record_root_in_trans+0x44/0x70 [btrfs]
__mutex_lock+0x7b/0x820
? btrfs_record_root_in_trans+0x44/0x70 [btrfs]
? kvm_sched_clock_read+0x14/0x30
? sched_clock+0x5/0x10
? sched_clock_cpu+0xc/0xb0
btrfs_record_root_in_trans+0x44/0x70 [btrfs]
start_transaction+0xd2/0x500 [btrfs]
btrfs_dirty_inode+0x44/0xd0 [btrfs]
file_update_time+0xc6/0x120
btrfs_page_mkwrite+0xda/0x560 [btrfs]
? sched_clock+0x5/0x10
do_page_mkwrite+0x4f/0x130
do_wp_page+0x3b0/0x4f0
handle_mm_fault+0xf47/0x1850
do_user_addr_fault+0x1fc/0x4b0
exc_page_fault+0x88/0x300
? asm_exc_page_fault+0x8/0x30
asm_exc_page_fault+0x1e/0x30
RIP: 0033:0x7fa3972fdbfe
Code: Bad RIP value.
Fix this by not holding the ->device_list_mutex at this point. The
device_list_mutex exists to protect us from modifying the device list
while the file system is running.
However it can also be modified by doing a scan on a device. But this
action is specifically protected by the uuid_mutex, which we are holding
here. We cannot race with opening at this point because we have the
->s_mount lock held during the mount. Not having the
->device_list_mutex here is perfectly safe as we're not going to change
the devices at this point.
CC: stable@vger.kernel.org # 4.19+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add some comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 4faf55b03823e96c44dc4e364520000ed3b12fdb upstream.
->show_devname currently shows the lowest devid in the list. As the seed
devices have the lowest devid in the sprouted filesystem, the userland
tool such as findmnt end up seeing seed device instead of the device from
the read-writable sprouted filesystem. As shown below.
mount /dev/sda /btrfs
mount: /btrfs: WARNING: device write-protected, mounted read-only.
findmnt --output SOURCE,TARGET,UUID /btrfs
SOURCE TARGET UUID
/dev/sda /btrfs 899f7027-3e46-4626-93e7-7d4c9ad19111
btrfs dev add -f /dev/sdb /btrfs
umount /btrfs
mount /dev/sdb /btrfs
findmnt --output SOURCE,TARGET,UUID /btrfs
SOURCE TARGET UUID
/dev/sda /btrfs 899f7027-3e46-4626-93e7-7d4c9ad19111
All sprouts from a single seed will show the same seed device and the
same fsid. That's confusing.
This is causing problems in our prototype as there isn't any reference
to the sprout file-system(s) which is being used for actual read and
write.
This was added in the patch which implemented the show_devname in btrfs
commit 9c5085c147 ("Btrfs: implement ->show_devname").
I tried to look for any particular reason that we need to show the seed
device, there isn't any.
So instead, do not traverse through the seed devices, just show the
lowest devid in the sprouted fsid.
After the patch:
mount /dev/sda /btrfs
mount: /btrfs: WARNING: device write-protected, mounted read-only.
findmnt --output SOURCE,TARGET,UUID /btrfs
SOURCE TARGET UUID
/dev/sda /btrfs 899f7027-3e46-4626-93e7-7d4c9ad19111
btrfs dev add -f /dev/sdb /btrfs
mount -o rw,remount /dev/sdb /btrfs
findmnt --output SOURCE,TARGET,UUID /btrfs
SOURCE TARGET UUID
/dev/sdb /btrfs 595ca0e6-b82e-46b5-b9e2-c72a6928be48
mount /dev/sda /btrfs1
mount: /btrfs1: WARNING: device write-protected, mounted read-only.
btrfs dev add -f /dev/sdc /btrfs1
findmnt --output SOURCE,TARGET,UUID /btrfs1
SOURCE TARGET UUID
/dev/sdc /btrfs1 ca1dbb7a-8446-4f95-853c-a20f3f82bdbb
cat /proc/self/mounts | grep btrfs
/dev/sdb /btrfs btrfs rw,relatime,noacl,space_cache,subvolid=5,subvol=/ 0 0
/dev/sdc /btrfs1 btrfs ro,relatime,noacl,space_cache,subvolid=5,subvol=/ 0 0
Reported-by: Martin K. Petersen <martin.petersen@oracle.com>
CC: stable@vger.kernel.org # 4.19+
Tested-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit d60ba8de1164e1b42e296ff270c622a070ef8fe7 upstream.
clang static analysis flags this error
fs/btrfs/ref-verify.c:290:3: warning: Potential leak of memory pointed to by 're' [unix.Malloc]
kfree(be);
^~~~~
The problem is in this block of code:
if (root_objectid) {
struct root_entry *exist_re;
exist_re = insert_root_entry(&exist->roots, re);
if (exist_re)
kfree(re);
}
There is no 'else' block freeing when root_objectid is 0. Add the
missing kfree to the else branch.
Fixes: fd708b81d9 ("Btrfs: add a extent ref verify tool")
CC: stable@vger.kernel.org # 4.19+
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 851fd730a743e072badaf67caf39883e32439431 upstream.
[BUG]
When a lot of subvolumes are created, there is a user report about
transaction aborted:
BTRFS: Transaction aborted (error -24)
WARNING: CPU: 17 PID: 17041 at fs/btrfs/transaction.c:1576 create_pending_snapshot+0xbc4/0xd10 [btrfs]
RIP: 0010:create_pending_snapshot+0xbc4/0xd10 [btrfs]
Call Trace:
create_pending_snapshots+0x82/0xa0 [btrfs]
btrfs_commit_transaction+0x275/0x8c0 [btrfs]
btrfs_mksubvol+0x4b9/0x500 [btrfs]
btrfs_ioctl_snap_create_transid+0x174/0x180 [btrfs]
btrfs_ioctl_snap_create_v2+0x11c/0x180 [btrfs]
btrfs_ioctl+0x11a4/0x2da0 [btrfs]
do_vfs_ioctl+0xa9/0x640
ksys_ioctl+0x67/0x90
__x64_sys_ioctl+0x1a/0x20
do_syscall_64+0x5a/0x110
entry_SYSCALL_64_after_hwframe+0x44/0xa9
---[ end trace 33f2f83f3d5250e9 ]---
BTRFS: error (device sda1) in create_pending_snapshot:1576: errno=-24 unknown
BTRFS info (device sda1): forced readonly
BTRFS warning (device sda1): Skipping commit of aborted transaction.
BTRFS: error (device sda1) in cleanup_transaction:1831: errno=-24 unknown
[CAUSE]
The error is EMFILE (Too many files open) and comes from the anonymous
block device allocation. The ids are in a shared pool of size 1<<20.
The ids are assigned to live subvolumes, ie. the root structure exists
in memory (eg. after creation or after the root appears in some path).
The pool could be exhausted if the numbers are not reclaimed fast
enough, after subvolume deletion or if other system component uses the
anon block devices.
[WORKAROUND]
Since it's not possible to completely solve the problem, we can only
minimize the time the id is allocated to a subvolume root.
Firstly, we can reduce the use of anon_dev by trees that are not
subvolume roots, like data reloc tree.
This patch will do extra check on root objectid, to skip roots that
don't need anon_dev. Currently it's only data reloc tree and orphan
roots.
Reported-by: Greed Rong <greedrong@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/CA+UqX+NTrZ6boGnWHhSeZmEY5J76CTqmYjO2S+=tHJX7nb9DPw@mail.gmail.com/
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 082b6c970f02fefd278c7833880cda29691a5f34 upstream.
[BUG]
When a lot of subvolumes are created, there is a user report about
transaction aborted caused by slow anonymous block device reclaim:
BTRFS: Transaction aborted (error -24)
WARNING: CPU: 17 PID: 17041 at fs/btrfs/transaction.c:1576 create_pending_snapshot+0xbc4/0xd10 [btrfs]
RIP: 0010:create_pending_snapshot+0xbc4/0xd10 [btrfs]
Call Trace:
create_pending_snapshots+0x82/0xa0 [btrfs]
btrfs_commit_transaction+0x275/0x8c0 [btrfs]
btrfs_mksubvol+0x4b9/0x500 [btrfs]
btrfs_ioctl_snap_create_transid+0x174/0x180 [btrfs]
btrfs_ioctl_snap_create_v2+0x11c/0x180 [btrfs]
btrfs_ioctl+0x11a4/0x2da0 [btrfs]
do_vfs_ioctl+0xa9/0x640
ksys_ioctl+0x67/0x90
__x64_sys_ioctl+0x1a/0x20
do_syscall_64+0x5a/0x110
entry_SYSCALL_64_after_hwframe+0x44/0xa9
---[ end trace 33f2f83f3d5250e9 ]---
BTRFS: error (device sda1) in create_pending_snapshot:1576: errno=-24 unknown
BTRFS info (device sda1): forced readonly
BTRFS warning (device sda1): Skipping commit of aborted transaction.
BTRFS: error (device sda1) in cleanup_transaction:1831: errno=-24 unknown
[CAUSE]
The anonymous device pool is shared and its size is 1M. It's possible to
hit that limit if the subvolume deletion is not fast enough and the
subvolumes to be cleaned keep the ids allocated.
[WORKAROUND]
We can't avoid the anon device pool exhaustion but we can shorten the
time the id is attached to the subvolume root once the subvolume becomes
invisible to the user.
Reported-by: Greed Rong <greedrong@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/CA+UqX+NTrZ6boGnWHhSeZmEY5J76CTqmYjO2S+=tHJX7nb9DPw@mail.gmail.com/
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9f7fec0ba89108b9385f1b9fb167861224912a4a ]
Some of the self tests create a test inode, setup some extents and then do
calls to btrfs_get_extent() to test that the corresponding extent maps
exist and are correct. However btrfs_get_extent(), since the 5.2 merge
window, now errors out when it finds a regular or prealloc extent for an
inode that does not correspond to a regular file (its ->i_mode is not
S_IFREG). This causes the self tests to fail sometimes, specially when
KASAN, slub_debug and page poisoning are enabled:
$ modprobe btrfs
modprobe: ERROR: could not insert 'btrfs': Invalid argument
$ dmesg
[ 9414.691648] Btrfs loaded, crc32c=crc32c-intel, debug=on, assert=on, integrity-checker=on, ref-verify=on
[ 9414.692655] BTRFS: selftest: sectorsize: 4096 nodesize: 4096
[ 9414.692658] BTRFS: selftest: running btrfs free space cache tests
[ 9414.692918] BTRFS: selftest: running extent only tests
[ 9414.693061] BTRFS: selftest: running bitmap only tests
[ 9414.693366] BTRFS: selftest: running bitmap and extent tests
[ 9414.696455] BTRFS: selftest: running space stealing from bitmap to extent tests
[ 9414.697131] BTRFS: selftest: running extent buffer operation tests
[ 9414.697133] BTRFS: selftest: running btrfs_split_item tests
[ 9414.697564] BTRFS: selftest: running extent I/O tests
[ 9414.697583] BTRFS: selftest: running find delalloc tests
[ 9415.081125] BTRFS: selftest: running find_first_clear_extent_bit test
[ 9415.081278] BTRFS: selftest: running extent buffer bitmap tests
[ 9415.124192] BTRFS: selftest: running inode tests
[ 9415.124195] BTRFS: selftest: running btrfs_get_extent tests
[ 9415.127909] BTRFS: selftest: running hole first btrfs_get_extent test
[ 9415.128343] BTRFS critical (device (efault)): regular/prealloc extent found for non-regular inode 256
[ 9415.131428] BTRFS: selftest: fs/btrfs/tests/inode-tests.c:904 expected a real extent, got 0
This happens because the test inodes are created without ever initializing
the i_mode field of the inode, and neither VFS's new_inode() nor the btrfs
callback btrfs_alloc_inode() initialize the i_mode. Initialization of the
i_mode is done through the various callbacks used by the VFS to create
new inodes (regular files, directories, symlinks, tmpfiles, etc), which
all call btrfs_new_inode() which in turn calls inode_init_owner(), which
sets the inode's i_mode. Since the tests only uses new_inode() to create
the test inodes, the i_mode was never initialized.
This always happens on a VM I used with kasan, slub_debug and many other
debug facilities enabled. It also happened to someone who reported this
on bugzilla (on a 5.3-rc).
Fix this by setting i_mode to S_IFREG at btrfs_new_test_inode().
Fixes: 6bf9e4bd6a2778 ("btrfs: inode: Verify inode mode to avoid NULL pointer dereference")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=204397
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6bf9e4bd6a277840d3fe8c5d5d530a1fbd3db592 ]
[BUG]
When accessing a file on a crafted image, btrfs can crash in block layer:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
PGD 136501067 P4D 136501067 PUD 124519067 PMD 0
CPU: 3 PID: 0 Comm: swapper/3 Not tainted 5.0.0-rc8-default #252
RIP: 0010:end_bio_extent_readpage+0x144/0x700
Call Trace:
<IRQ>
blk_update_request+0x8f/0x350
blk_mq_end_request+0x1a/0x120
blk_done_softirq+0x99/0xc0
__do_softirq+0xc7/0x467
irq_exit+0xd1/0xe0
call_function_single_interrupt+0xf/0x20
</IRQ>
RIP: 0010:default_idle+0x1e/0x170
[CAUSE]
The crafted image has a tricky corruption, the INODE_ITEM has a
different type against its parent dir:
item 20 key (268 INODE_ITEM 0) itemoff 2808 itemsize 160
generation 13 transid 13 size 1048576 nbytes 1048576
block group 0 mode 121644 links 1 uid 0 gid 0 rdev 0
sequence 9 flags 0x0(none)
This mode number 0120000 means it's a symlink.
But the dir item think it's still a regular file:
item 8 key (264 DIR_INDEX 5) itemoff 3707 itemsize 32
location key (268 INODE_ITEM 0) type FILE
transid 13 data_len 0 name_len 2
name: f4
item 40 key (264 DIR_ITEM 51821248) itemoff 1573 itemsize 32
location key (268 INODE_ITEM 0) type FILE
transid 13 data_len 0 name_len 2
name: f4
For symlink, we don't set BTRFS_I(inode)->io_tree.ops and leave it
empty, as symlink is only designed to have inlined extent, all handled
by tree block read. Thus no need to trigger btrfs_submit_bio_hook() for
inline file extent.
However end_bio_extent_readpage() expects tree->ops populated, as it's
reading regular data extent. This causes NULL pointer dereference.
[FIX]
This patch fixes the problem in two ways:
- Verify inode mode against its dir item when looking up inode
So in btrfs_lookup_dentry() if we find inode mode mismatch with dir
item, we error out so that corrupted inode will not be accessed.
- Verify inode mode when getting extent mapping
Only regular file should have regular or preallocated extent.
If we found regular/preallocated file extent for symlink or
the rest, we error out before submitting the read bio.
With this fix that crafted image can be rejected gracefully:
BTRFS critical (device loop0): inode mode mismatch with dir: inode mode=0121644 btrfs type=7 dir type=1
Reported-by: Yoon Jungyeon <jungyeon@gatech.edu>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=202763
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 5909ca110b29aa16b23b52b8de8d3bb1035fd738 upstream.
When locking pages for delalloc, we check if it's dirty and mapping still
matches. If it does not match, we need to return -EAGAIN and release all
pages. Only the current page was put though, iterate over all the
remaining pages too.
CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Robbie Ko <robbieko@synology.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 48cfa61b58a1fee0bc49eef04f8ccf31493b7cdd upstream.
It is possible to cause a btrfs mount to fail by racing it with a slow
umount. The crux of the sequence is generic_shutdown_super not yet
calling sop->put_super before btrfs_mount_root calls btrfs_open_devices.
If that occurs, btrfs_open_devices will decide the opened counter is
non-zero, increment it, and skip resetting fs_devices->total_rw_bytes to
0. From here, mount will call sget which will result in grab_super
trying to take the super block umount semaphore. That semaphore will be
held by the slow umount, so mount will block. Before up-ing the
semaphore, umount will delete the super block, resulting in mount's sget
reliably allocating a new one, which causes the mount path to dutifully
fill it out, and increment total_rw_bytes a second time, which causes
the mount to fail, as we see double the expected bytes.
Here is the sequence laid out in greater detail:
CPU0 CPU1
down_write sb->s_umount
btrfs_kill_super
kill_anon_super(sb)
generic_shutdown_super(sb);
shrink_dcache_for_umount(sb);
sync_filesystem(sb);
evict_inodes(sb); // SLOW
btrfs_mount_root
btrfs_scan_one_device
fs_devices = device->fs_devices
fs_info->fs_devices = fs_devices
// fs_devices-opened makes this a no-op
btrfs_open_devices(fs_devices, mode, fs_type)
s = sget(fs_type, test, set, flags, fs_info);
find sb in s_instances
grab_super(sb);
down_write(&s->s_umount); // blocks
sop->put_super(sb)
// sb->fs_devices->opened == 2; no-op
spin_lock(&sb_lock);
hlist_del_init(&sb->s_instances);
spin_unlock(&sb_lock);
up_write(&sb->s_umount);
return 0;
retry lookup
don't find sb in s_instances (deleted by CPU0)
s = alloc_super
return s;
btrfs_fill_super(s, fs_devices, data)
open_ctree // fs_devices total_rw_bytes improperly set!
btrfs_read_chunk_tree
read_one_dev // increment total_rw_bytes again!!
super_total_bytes < fs_devices->total_rw_bytes // ERROR!!!
To fix this, we clear total_rw_bytes from within btrfs_read_chunk_tree
before the calls to read_one_dev, while holding the sb umount semaphore
and the uuid mutex.
To reproduce, it is sufficient to dirty a decent number of inodes, then
quickly umount and mount.
for i in $(seq 0 500)
do
dd if=/dev/zero of="/mnt/foo/$i" bs=1M count=1
done
umount /mnt/foo&
mount /mnt/foo
does the trick for me.
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Boris Burkov <boris@bur.io>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6bf9cd2eed9aee6d742bb9296c994a91f5316949 upstream.
Under somewhat convoluted conditions, it is possible to attempt to
release an extent_buffer that is under io, which triggers a BUG_ON in
btrfs_release_extent_buffer_pages.
This relies on a few different factors. First, extent_buffer reads done
as readahead for searching use WAIT_NONE, so they free the local extent
buffer reference while the io is outstanding. However, they should still
be protected by TREE_REF. However, if the system is doing signficant
reclaim, and simultaneously heavily accessing the extent_buffers, it is
possible for releasepage to race with two concurrent readahead attempts
in a way that leaves TREE_REF unset when the readahead extent buffer is
released.
Essentially, if two tasks race to allocate a new extent_buffer, but the
winner who attempts the first io is rebuffed by a page being locked
(likely by the reclaim itself) then the loser will still go ahead with
issuing the readahead. The loser's call to find_extent_buffer must also
race with the reclaim task reading the extent_buffer's refcount as 1 in
a way that allows the reclaim to re-clear the TREE_REF checked by
find_extent_buffer.
The following represents an example execution demonstrating the race:
CPU0 CPU1 CPU2
reada_for_search reada_for_search
readahead_tree_block readahead_tree_block
find_create_tree_block find_create_tree_block
alloc_extent_buffer alloc_extent_buffer
find_extent_buffer // not found
allocates eb
lock pages
associate pages to eb
insert eb into radix tree
set TREE_REF, refs == 2
unlock pages
read_extent_buffer_pages // WAIT_NONE
not uptodate (brand new eb)
lock_page
if !trylock_page
goto unlock_exit // not an error
free_extent_buffer
release_extent_buffer
atomic_dec_and_test refs to 1
find_extent_buffer // found
try_release_extent_buffer
take refs_lock
reads refs == 1; no io
atomic_inc_not_zero refs to 2
mark_buffer_accessed
check_buffer_tree_ref
// not STALE, won't take refs_lock
refs == 2; TREE_REF set // no action
read_extent_buffer_pages // WAIT_NONE
clear TREE_REF
release_extent_buffer
atomic_dec_and_test refs to 1
unlock_page
still not uptodate (CPU1 read failed on trylock_page)
locks pages
set io_pages > 0
submit io
return
free_extent_buffer
release_extent_buffer
dec refs to 0
delete from radix tree
btrfs_release_extent_buffer_pages
BUG_ON(io_pages > 0)!!!
We observe this at a very low rate in production and were also able to
reproduce it in a test environment by introducing some spurious delays
and by introducing probabilistic trylock_page failures.
To fix it, we apply check_tree_ref at a point where it could not
possibly be unset by a competing task: after io_pages has been
incremented. All the codepaths that clear TREE_REF check for io, so they
would not be able to clear it after this point until the io is done.
Stack trace, for reference:
[1417839.424739] ------------[ cut here ]------------
[1417839.435328] kernel BUG at fs/btrfs/extent_io.c:4841!
[1417839.447024] invalid opcode: 0000 [#1] SMP
[1417839.502972] RIP: 0010:btrfs_release_extent_buffer_pages+0x20/0x1f0
[1417839.517008] Code: ed e9 ...
[1417839.558895] RSP: 0018:ffffc90020bcf798 EFLAGS: 00010202
[1417839.570816] RAX: 0000000000000002 RBX: ffff888102d6def0 RCX: 0000000000000028
[1417839.586962] RDX: 0000000000000002 RSI: ffff8887f0296482 RDI: ffff888102d6def0
[1417839.603108] RBP: ffff88885664a000 R08: 0000000000000046 R09: 0000000000000238
[1417839.619255] R10: 0000000000000028 R11: ffff88885664af68 R12: 0000000000000000
[1417839.635402] R13: 0000000000000000 R14: ffff88875f573ad0 R15: ffff888797aafd90
[1417839.651549] FS: 00007f5a844fa700(0000) GS:ffff88885f680000(0000) knlGS:0000000000000000
[1417839.669810] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[1417839.682887] CR2: 00007f7884541fe0 CR3: 000000049f609002 CR4: 00000000003606e0
[1417839.699037] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[1417839.715187] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[1417839.731320] Call Trace:
[1417839.737103] release_extent_buffer+0x39/0x90
[1417839.746913] read_block_for_search.isra.38+0x2a3/0x370
[1417839.758645] btrfs_search_slot+0x260/0x9b0
[1417839.768054] btrfs_lookup_file_extent+0x4a/0x70
[1417839.778427] btrfs_get_extent+0x15f/0x830
[1417839.787665] ? submit_extent_page+0xc4/0x1c0
[1417839.797474] ? __do_readpage+0x299/0x7a0
[1417839.806515] __do_readpage+0x33b/0x7a0
[1417839.815171] ? btrfs_releasepage+0x70/0x70
[1417839.824597] extent_readpages+0x28f/0x400
[1417839.833836] read_pages+0x6a/0x1c0
[1417839.841729] ? startup_64+0x2/0x30
[1417839.849624] __do_page_cache_readahead+0x13c/0x1a0
[1417839.860590] filemap_fault+0x6c7/0x990
[1417839.869252] ? xas_load+0x8/0x80
[1417839.876756] ? xas_find+0x150/0x190
[1417839.884839] ? filemap_map_pages+0x295/0x3b0
[1417839.894652] __do_fault+0x32/0x110
[1417839.902540] __handle_mm_fault+0xacd/0x1000
[1417839.912156] handle_mm_fault+0xaa/0x1c0
[1417839.921004] __do_page_fault+0x242/0x4b0
[1417839.930044] ? page_fault+0x8/0x30
[1417839.937933] page_fault+0x1e/0x30
[1417839.945631] RIP: 0033:0x33c4bae
[1417839.952927] Code: Bad RIP value.
[1417839.960411] RSP: 002b:00007f5a844f7350 EFLAGS: 00010206
[1417839.972331] RAX: 000000000000006e RBX: 1614b3ff6a50398a RCX: 0000000000000000
[1417839.988477] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000002
[1417840.004626] RBP: 00007f5a844f7420 R08: 000000000000006e R09: 00007f5a94aeccb8
[1417840.020784] R10: 00007f5a844f7350 R11: 0000000000000000 R12: 00007f5a94aecc79
[1417840.036932] R13: 00007f5a94aecc78 R14: 00007f5a94aecc90 R15: 00007f5a94aecc40
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9fecd13202f520f3f25d5b1c313adb740fe19773 ]
When removing a block group, if we fail to delete the block group's item
from the extent tree, we jump to the 'out' label and end up decrementing
the block group's reference count once only (by 1), resulting in a counter
leak because the block group at that point was already removed from the
block group cache rbtree - so we have to decrement the reference count
twice, once for the rbtree and once for our lookup at the start of the
function.
There is a second bug where if removing the free space tree entries (the
call to remove_block_group_free_space()) fails we end up jumping to the
'out_put_group' label but end up decrementing the reference count only
once, when we should have done it twice, since we have already removed
the block group from the block group cache rbtree. This happens because
the reference count decrement for the rbtree reference happens after
attempting to remove the free space tree entries, which is far away from
the place where we remove the block group from the rbtree.
To make things less error prone, decrement the reference count for the
rbtree immediately after removing the block group from it. This also
eleminates the need for two different exit labels on error, renaming
'out_put_label' to just 'out' and removing the old 'out'.
Fixes: f6033c5e333238 ("btrfs: fix block group leak when removing fails")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 4b1946284dd6641afdb9457101056d9e6ee6204c upstream.
If we attempt to write to prealloc extent located after eof using a
RWF_NOWAIT write, we always fail with -EAGAIN.
We do actually check if we have an allocated extent for the write at
the start of btrfs_file_write_iter() through a call to check_can_nocow(),
but later when we go into the actual direct IO write path we simply
return -EAGAIN if the write starts at or beyond EOF.
Trivial to reproduce:
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
$ touch /mnt/foo
$ chattr +C /mnt/foo
$ xfs_io -d -c "pwrite -S 0xab 0 64K" /mnt/foo
wrote 65536/65536 bytes at offset 0
64 KiB, 16 ops; 0.0004 sec (135.575 MiB/sec and 34707.1584 ops/sec)
$ xfs_io -c "falloc -k 64K 1M" /mnt/foo
$ xfs_io -d -c "pwrite -N -V 1 -S 0xfe -b 64K 64K 64K" /mnt/foo
pwrite: Resource temporarily unavailable
On xfs and ext4 the write succeeds, as expected.
Fix this by removing the wrong check at btrfs_direct_IO().
Fixes: edf064e7c6 ("btrfs: nowait aio support")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 432cd2a10f1c10cead91fe706ff5dc52f06d642a upstream.
When running relocation of a data block group while scrub is running in
parallel, it is possible that the relocation will fail and abort the
current transaction with an -EINVAL error:
[134243.988595] BTRFS info (device sdc): found 14 extents, stage: move data extents
[134243.999871] ------------[ cut here ]------------
[134244.000741] BTRFS: Transaction aborted (error -22)
[134244.001692] WARNING: CPU: 0 PID: 26954 at fs/btrfs/ctree.c:1071 __btrfs_cow_block+0x6a7/0x790 [btrfs]
[134244.003380] Modules linked in: btrfs blake2b_generic xor raid6_pq (...)
[134244.012577] CPU: 0 PID: 26954 Comm: btrfs Tainted: G W 5.6.0-rc7-btrfs-next-58 #5
[134244.014162] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
[134244.016184] RIP: 0010:__btrfs_cow_block+0x6a7/0x790 [btrfs]
[134244.017151] Code: 48 c7 c7 (...)
[134244.020549] RSP: 0018:ffffa41607863888 EFLAGS: 00010286
[134244.021515] RAX: 0000000000000000 RBX: ffff9614bdfe09c8 RCX: 0000000000000000
[134244.022822] RDX: 0000000000000001 RSI: ffffffffb3d63980 RDI: 0000000000000001
[134244.024124] RBP: ffff961589e8c000 R08: 0000000000000000 R09: 0000000000000001
[134244.025424] R10: ffffffffc0ae5955 R11: 0000000000000000 R12: ffff9614bd530d08
[134244.026725] R13: ffff9614ced41b88 R14: ffff9614bdfe2a48 R15: 0000000000000000
[134244.028024] FS: 00007f29b63c08c0(0000) GS:ffff9615ba600000(0000) knlGS:0000000000000000
[134244.029491] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[134244.030560] CR2: 00007f4eb339b000 CR3: 0000000130d6e006 CR4: 00000000003606f0
[134244.031997] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[134244.033153] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[134244.034484] Call Trace:
[134244.034984] btrfs_cow_block+0x12b/0x2b0 [btrfs]
[134244.035859] do_relocation+0x30b/0x790 [btrfs]
[134244.036681] ? do_raw_spin_unlock+0x49/0xc0
[134244.037460] ? _raw_spin_unlock+0x29/0x40
[134244.038235] relocate_tree_blocks+0x37b/0x730 [btrfs]
[134244.039245] relocate_block_group+0x388/0x770 [btrfs]
[134244.040228] btrfs_relocate_block_group+0x161/0x2e0 [btrfs]
[134244.041323] btrfs_relocate_chunk+0x36/0x110 [btrfs]
[134244.041345] btrfs_balance+0xc06/0x1860 [btrfs]
[134244.043382] ? btrfs_ioctl_balance+0x27c/0x310 [btrfs]
[134244.045586] btrfs_ioctl_balance+0x1ed/0x310 [btrfs]
[134244.045611] btrfs_ioctl+0x1880/0x3760 [btrfs]
[134244.049043] ? do_raw_spin_unlock+0x49/0xc0
[134244.049838] ? _raw_spin_unlock+0x29/0x40
[134244.050587] ? __handle_mm_fault+0x11b3/0x14b0
[134244.051417] ? ksys_ioctl+0x92/0xb0
[134244.052070] ksys_ioctl+0x92/0xb0
[134244.052701] ? trace_hardirqs_off_thunk+0x1a/0x1c
[134244.053511] __x64_sys_ioctl+0x16/0x20
[134244.054206] do_syscall_64+0x5c/0x280
[134244.054891] entry_SYSCALL_64_after_hwframe+0x49/0xbe
[134244.055819] RIP: 0033:0x7f29b51c9dd7
[134244.056491] Code: 00 00 00 (...)
[134244.059767] RSP: 002b:00007ffcccc1dd08 EFLAGS: 00000202 ORIG_RAX: 0000000000000010
[134244.061168] RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f29b51c9dd7
[134244.062474] RDX: 00007ffcccc1dda0 RSI: 00000000c4009420 RDI: 0000000000000003
[134244.063771] RBP: 0000000000000003 R08: 00005565cea4b000 R09: 0000000000000000
[134244.065032] R10: 0000000000000541 R11: 0000000000000202 R12: 00007ffcccc2060a
[134244.066327] R13: 00007ffcccc1dda0 R14: 0000000000000002 R15: 00007ffcccc1dec0
[134244.067626] irq event stamp: 0
[134244.068202] hardirqs last enabled at (0): [<0000000000000000>] 0x0
[134244.069351] hardirqs last disabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020
[134244.070909] softirqs last enabled at (0): [<ffffffffb2abdedf>] copy_process+0x74f/0x2020
[134244.072392] softirqs last disabled at (0): [<0000000000000000>] 0x0
[134244.073432] ---[ end trace bd7c03622e0b0a99 ]---
The -EINVAL error comes from the following chain of function calls:
__btrfs_cow_block() <-- aborts the transaction
btrfs_reloc_cow_block()
replace_file_extents()
get_new_location() <-- returns -EINVAL
When relocating a data block group, for each allocated extent of the block
group, we preallocate another extent (at prealloc_file_extent_cluster()),
associated with the data relocation inode, and then dirty all its pages.
These preallocated extents have, and must have, the same size that extents
from the data block group being relocated have.
Later before we start the relocation stage that updates pointers (bytenr
field of file extent items) to point to the the new extents, we trigger
writeback for the data relocation inode. The expectation is that writeback
will write the pages to the previously preallocated extents, that it
follows the NOCOW path. That is generally the case, however, if a scrub
is running it may have turned the block group that contains those extents
into RO mode, in which case writeback falls back to the COW path.
However in the COW path instead of allocating exactly one extent with the
expected size, the allocator may end up allocating several smaller extents
due to free space fragmentation - because we tell it at cow_file_range()
that the minimum allocation size can match the filesystem's sector size.
This later breaks the relocation's expectation that an extent associated
to a file extent item in the data relocation inode has the same size as
the respective extent pointed by a file extent item in another tree - in
this case the extent to which the relocation inode poins to is smaller,
causing relocation.c:get_new_location() to return -EINVAL.
For example, if we are relocating a data block group X that has a logical
address of X and the block group has an extent allocated at the logical
address X + 128KiB with a size of 64KiB:
1) At prealloc_file_extent_cluster() we allocate an extent for the data
relocation inode with a size of 64KiB and associate it to the file
offset 128KiB (X + 128KiB - X) of the data relocation inode. This
preallocated extent was allocated at block group Z;
2) A scrub running in parallel turns block group Z into RO mode and
starts scrubing its extents;
3) Relocation triggers writeback for the data relocation inode;
4) When running delalloc (btrfs_run_delalloc_range()), we try first the
NOCOW path because the data relocation inode has BTRFS_INODE_PREALLOC
set in its flags. However, because block group Z is in RO mode, the
NOCOW path (run_delalloc_nocow()) falls back into the COW path, by
calling cow_file_range();
5) At cow_file_range(), in the first iteration of the while loop we call
btrfs_reserve_extent() to allocate a 64KiB extent and pass it a minimum
allocation size of 4KiB (fs_info->sectorsize). Due to free space
fragmentation, btrfs_reserve_extent() ends up allocating two extents
of 32KiB each, each one on a different iteration of that while loop;
6) Writeback of the data relocation inode completes;
7) Relocation proceeds and ends up at relocation.c:replace_file_extents(),
with a leaf which has a file extent item that points to the data extent
from block group X, that has a logical address (bytenr) of X + 128KiB
and a size of 64KiB. Then it calls get_new_location(), which does a
lookup in the data relocation tree for a file extent item starting at
offset 128KiB (X + 128KiB - X) and belonging to the data relocation
inode. It finds a corresponding file extent item, however that item
points to an extent that has a size of 32KiB, which doesn't match the
expected size of 64KiB, resuling in -EINVAL being returned from this
function and propagated up to __btrfs_cow_block(), which aborts the
current transaction.
To fix this make sure that at cow_file_range() when we call the allocator
we pass it a minimum allocation size corresponding the desired extent size
if the inode belongs to the data relocation tree, otherwise pass it the
filesystem's sector size as the minimum allocation size.
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e2c8e92d1140754073ad3799eb6620c76bab2078 ]
If an error happens while running dellaloc in COW mode for a range, we can
end up calling extent_clear_unlock_delalloc() for a range that goes beyond
our range's end offset by 1 byte, which affects 1 extra page. This results
in clearing bits and doing page operations (such as a page unlock) outside
our target range.
Fix that by calling extent_clear_unlock_delalloc() with an inclusive end
offset, instead of an exclusive end offset, at cow_file_range().
Fixes: a315e68f6e ("Btrfs: fix invalid attempt to free reserved space on failure to cow range")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 6d3113a193e3385c72240096fe397618ecab6e43 ]
In btrfs_submit_direct_hook(), if a direct I/O write doesn't span a RAID
stripe or chunk, we submit orig_bio without cloning it. In this case, we
don't increment pending_bios. Then, if btrfs_submit_dio_bio() fails, we
decrement pending_bios to -1, and we never complete orig_bio. Fix it by
initializing pending_bios to 1 instead of incrementing later.
Fixing this exposes another bug: we put orig_bio prematurely and then
put it again from end_io. Fix it by not putting orig_bio.
After this change, pending_bios is really more of a reference count, but
I'll leave that cleanup separate to keep the fix small.
Fixes: e65e153554 ("btrfs: fix panic caused by direct IO")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 89efda52e6b6930f80f5adda9c3c9edfb1397191 upstream.
Whenever a chown is executed, all capabilities of the file being touched
are lost. When doing incremental send with a file with capabilities,
there is a situation where the capability can be lost on the receiving
side. The sequence of actions bellow shows the problem:
$ mount /dev/sda fs1
$ mount /dev/sdb fs2
$ touch fs1/foo.bar
$ setcap cap_sys_nice+ep fs1/foo.bar
$ btrfs subvolume snapshot -r fs1 fs1/snap_init
$ btrfs send fs1/snap_init | btrfs receive fs2
$ chgrp adm fs1/foo.bar
$ setcap cap_sys_nice+ep fs1/foo.bar
$ btrfs subvolume snapshot -r fs1 fs1/snap_complete
$ btrfs subvolume snapshot -r fs1 fs1/snap_incremental
$ btrfs send fs1/snap_complete | btrfs receive fs2
$ btrfs send -p fs1/snap_init fs1/snap_incremental | btrfs receive fs2
At this point, only a chown was emitted by "btrfs send" since only the
group was changed. This makes the cap_sys_nice capability to be dropped
from fs2/snap_incremental/foo.bar
To fix that, only emit capabilities after chown is emitted. The current
code first checks for xattrs that are new/changed, emits them, and later
emit the chown. Now, __process_new_xattr skips capabilities, letting
only finish_inode_if_needed to emit them, if they exist, for the inode
being processed.
This behavior was being worked around in "btrfs receive" side by caching
the capability and only applying it after chown. Now, xattrs are only
emmited _after_ chown, making that workaround not needed anymore.
Link: https://github.com/kdave/btrfs-progs/issues/202
CC: stable@vger.kernel.org # 4.4+
Suggested-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Marcos Paulo de Souza <mpdesouza@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 998a0671961f66e9fad4990ed75f80ba3088c2f1 upstream.
btrfs_free_extra_devids() updates fs_devices::latest_bdev to point to
the bdev with greatest device::generation number. For a typical-missing
device the generation number is zero so fs_devices::latest_bdev will
never point to it.
But if the missing device is due to alienation [1], then
device::generation is not zero and if it is greater or equal to the rest
of device generations in the list, then fs_devices::latest_bdev ends up
pointing to the missing device and reports the error like [2].
[1] We maintain devices of a fsid (as in fs_device::fsid) in the
fs_devices::devices list, a device is considered as an alien device
if its fsid does not match with the fs_device::fsid
Consider a working filesystem with raid1:
$ mkfs.btrfs -f -d raid1 -m raid1 /dev/sda /dev/sdb
$ mount /dev/sda /mnt-raid1
$ umount /mnt-raid1
While mnt-raid1 was unmounted the user force-adds one of its devices to
another btrfs filesystem:
$ mkfs.btrfs -f /dev/sdc
$ mount /dev/sdc /mnt-single
$ btrfs dev add -f /dev/sda /mnt-single
Now the original mnt-raid1 fails to mount in degraded mode, because
fs_devices::latest_bdev is pointing to the alien device.
$ mount -o degraded /dev/sdb /mnt-raid1
[2]
mount: wrong fs type, bad option, bad superblock on /dev/sdb,
missing codepage or helper program, or other error
In some cases useful info is found in syslog - try
dmesg | tail or so.
kernel: BTRFS warning (device sdb): devid 1 uuid 072a0192-675b-4d5a-8640-a5cf2b2c704d is missing
kernel: BTRFS error (device sdb): failed to read devices
kernel: BTRFS error (device sdb): open_ctree failed
Fix the root cause by checking if the device is not missing before it
can be considered for the fs_devices::latest_bdev.
CC: stable@vger.kernel.org # 4.19+
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit cbab8ade585a18c4334b085564d9d046e01a3f70 ]
[BUG]
For the following operation, qgroup is guaranteed to be screwed up due
to snapshot adding to a new qgroup:
# mkfs.btrfs -f $dev
# mount $dev $mnt
# btrfs qgroup en $mnt
# btrfs subv create $mnt/src
# xfs_io -f -c "pwrite 0 1m" $mnt/src/file
# sync
# btrfs qgroup create 1/0 $mnt/src
# btrfs subv snapshot -i 1/0 $mnt/src $mnt/snapshot
# btrfs qgroup show -prce $mnt/src
qgroupid rfer excl max_rfer max_excl parent child
-------- ---- ---- -------- -------- ------ -----
0/5 16.00KiB 16.00KiB none none --- ---
0/257 1.02MiB 16.00KiB none none --- ---
0/258 1.02MiB 16.00KiB none none 1/0 ---
1/0 0.00B 0.00B none none --- 0/258
^^^^^^^^^^^^^^^^^^^^
[CAUSE]
The problem is in btrfs_qgroup_inherit(), we don't have good enough
check to determine if the new relation would break the existing
accounting.
Unlike btrfs_add_qgroup_relation(), which has proper check to determine
if we can do quick update without a rescan, in btrfs_qgroup_inherit() we
can even assign a snapshot to multiple qgroups.
[FIX]
Fix it by manually marking qgroup inconsistent for snapshot inheritance.
For subvolume creation, since all its extents are exclusively owned, we
don't need to rescan.
In theory, we should call relation check like quick_update_accounting()
when doing qgroup inheritance and inform user about qgroup accounting
inconsistency.
But we don't have good mechanism to relay that back to the user in the
snapshot creation context, thus we can only silently mark the qgroup
inconsistent.
Anyway, user shouldn't use qgroup inheritance during snapshot creation,
and should add qgroup relationship after snapshot creation by 'btrfs
qgroup assign', which has a much better UI to inform user about qgroup
inconsistent and kick in rescan automatically.
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 7e4a3f7ed5d54926ec671bbb13e171cfe179cc50 ]
We are currently treating any non-zero return value from btrfs_next_leaf()
the same way, by going to the code that inserts a new checksum item in the
tree. However if btrfs_next_leaf() returns an error (a value < 0), we
should just stop and return the error, and not behave as if nothing has
happened, since in that case we do not have a way to know if there is a
next leaf or we are currently at the last leaf already.
So fix that by returning the error from btrfs_next_leaf().
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit f556faa46eb4e96d0d0772e74ecf66781e132f72 ]
Although we have tree level check at tree read runtime, it's completely
based on its parent level.
We still need to do accurate level check to avoid invalid tree blocks
sneak into kernel space.
The check itself is simple, for leaf its level should always be 0.
For nodes its level should be in range [1, BTRFS_MAX_LEVEL - 1].
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Su Yue <suy.fnst@cn.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 09ba3bc9dd150457c506e4661380a6183af651c1 upstream.
Both btrfs_find_device() and find_device() does the same thing except
that the latter does not take the seed device onto account in the device
scanning context. We can merge them.
Signed-off-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
[4.19.y backport notes:
Vikash : - To apply this patch, a portion of commit e4319cd9cace
was used to change the first argument of function
"btrfs_find_device" from "struct btrfs_fs_info" to
"struct btrfs_fs_devices".
Signed-off-by: Vikash Bansal <bvikas@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit fcc99734d1d4ced30167eb02e17f656735cb9928 upstream.
[BUG]
One run of btrfs/063 triggered the following lockdep warning:
============================================
WARNING: possible recursive locking detected
5.6.0-rc7-custom+ #48 Not tainted
--------------------------------------------
kworker/u24:0/7 is trying to acquire lock:
ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]
but task is already holding lock:
ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(sb_internal#2);
lock(sb_internal#2);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by kworker/u24:0/7:
#0: ffff88817b495948 ((wq_completion)btrfs-endio-write){+.+.}, at: process_one_work+0x557/0xb80
#1: ffff888189ea7db8 ((work_completion)(&work->normal_work)){+.+.}, at: process_one_work+0x557/0xb80
#2: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]
#3: ffff888174ca4da8 (&fs_info->reloc_mutex){+.+.}, at: btrfs_record_root_in_trans+0x83/0xd0 [btrfs]
stack backtrace:
CPU: 0 PID: 7 Comm: kworker/u24:0 Not tainted 5.6.0-rc7-custom+ #48
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
Call Trace:
dump_stack+0xc2/0x11a
__lock_acquire.cold+0xce/0x214
lock_acquire+0xe6/0x210
__sb_start_write+0x14e/0x290
start_transaction+0x66c/0x890 [btrfs]
btrfs_join_transaction+0x1d/0x20 [btrfs]
find_free_extent+0x1504/0x1a50 [btrfs]
btrfs_reserve_extent+0xd5/0x1f0 [btrfs]
btrfs_alloc_tree_block+0x1ac/0x570 [btrfs]
btrfs_copy_root+0x213/0x580 [btrfs]
create_reloc_root+0x3bd/0x470 [btrfs]
btrfs_init_reloc_root+0x2d2/0x310 [btrfs]
record_root_in_trans+0x191/0x1d0 [btrfs]
btrfs_record_root_in_trans+0x90/0xd0 [btrfs]
start_transaction+0x16e/0x890 [btrfs]
btrfs_join_transaction+0x1d/0x20 [btrfs]
btrfs_finish_ordered_io+0x55d/0xcd0 [btrfs]
finish_ordered_fn+0x15/0x20 [btrfs]
btrfs_work_helper+0x116/0x9a0 [btrfs]
process_one_work+0x632/0xb80
worker_thread+0x80/0x690
kthread+0x1a3/0x1f0
ret_from_fork+0x27/0x50
It's pretty hard to reproduce, only one hit so far.
[CAUSE]
This is because we're calling btrfs_join_transaction() without re-using
the current running one:
btrfs_finish_ordered_io()
|- btrfs_join_transaction() <<< Call #1
|- btrfs_record_root_in_trans()
|- btrfs_reserve_extent()
|- btrfs_join_transaction() <<< Call #2
Normally such btrfs_join_transaction() call should re-use the existing
one, without trying to re-start a transaction.
But the problem is, in btrfs_join_transaction() call #1, we call
btrfs_record_root_in_trans() before initializing current::journal_info.
And in btrfs_join_transaction() call #2, we're relying on
current::journal_info to avoid such deadlock.
[FIX]
Call btrfs_record_root_in_trans() after we have initialized
current::journal_info.
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f135cea30de5f74d5bfb5116682073841fb4af8f upstream.
When we have an inode with a prealloc extent that starts at an offset
lower than the i_size and there is another prealloc extent that starts at
an offset beyond i_size, we can end up losing part of the first prealloc
extent (the part that starts at i_size) and have an implicit hole if we
fsync the file and then have a power failure.
Consider the following example with comments explaining how and why it
happens.
$ mkfs.btrfs -f /dev/sdb
$ mount /dev/sdb /mnt
# Create our test file with 2 consecutive prealloc extents, each with a
# size of 128Kb, and covering the range from 0 to 256Kb, with a file
# size of 0.
$ xfs_io -f -c "falloc -k 0 128K" /mnt/foo
$ xfs_io -c "falloc -k 128K 128K" /mnt/foo
# Fsync the file to record both extents in the log tree.
$ xfs_io -c "fsync" /mnt/foo
# Now do a redudant extent allocation for the range from 0 to 64Kb.
# This will merely increase the file size from 0 to 64Kb. Instead we
# could also do a truncate to set the file size to 64Kb.
$ xfs_io -c "falloc 0 64K" /mnt/foo
# Fsync the file, so we update the inode item in the log tree with the
# new file size (64Kb). This also ends up setting the number of bytes
# for the first prealloc extent to 64Kb. This is done by the truncation
# at btrfs_log_prealloc_extents().
# This means that if a power failure happens after this, a write into
# the file range 64Kb to 128Kb will not use the prealloc extent and
# will result in allocation of a new extent.
$ xfs_io -c "fsync" /mnt/foo
# Now set the file size to 256K with a truncate and then fsync the file.
# Since no changes happened to the extents, the fsync only updates the
# i_size in the inode item at the log tree. This results in an implicit
# hole for the file range from 64Kb to 128Kb, something which fsck will
# complain when not using the NO_HOLES feature if we replay the log
# after a power failure.
$ xfs_io -c "truncate 256K" -c "fsync" /mnt/foo
So instead of always truncating the log to the inode's current i_size at
btrfs_log_prealloc_extents(), check first if there's a prealloc extent
that starts at an offset lower than the i_size and with a length that
crosses the i_size - if there is one, just make sure we truncate to a
size that corresponds to the end offset of that prealloc extent, so
that we don't lose the part of that extent that starts at i_size if a
power failure happens.
A test case for fstests follows soon.
Fixes: 31d11b83b9 ("Btrfs: fix duplicate extents after fsync of file with prealloc extents")
CC: stable@vger.kernel.org # 4.14+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f6033c5e333238f299c3ae03fac8cc1365b23b77 upstream.
btrfs_remove_block_group() invokes btrfs_lookup_block_group(), which
returns a local reference of the block group that contains the given
bytenr to "block_group" with increased refcount.
When btrfs_remove_block_group() returns, "block_group" becomes invalid,
so the refcount should be decreased to keep refcount balanced.
The reference counting issue happens in several exception handling paths
of btrfs_remove_block_group(). When those error scenarios occur such as
btrfs_alloc_path() returns NULL, the function forgets to decrease its
refcnt increased by btrfs_lookup_block_group() and will cause a refcnt
leak.
Fix this issue by jumping to "out_put_group" label and calling
btrfs_put_block_group() when those error scenarios occur.
CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Qu Wenruo
David Sterba
Filipe Manana
Josef Bacik
Nikolay Borisov
Marcos Paulo de Souza
Pavel Machek
Anand Jain
Tom Rix
Paul E. McKenney
Robbie Ko
Boris Burkov
Omar Sandoval
Xiyu Yang