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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- fix potential NULL pointer dereference when replaying tree log after
an error
- release path before initializing extent tree to avoid potential
deadlock when allocating new inode
- on filesystems with block size > page size
- fix potential read out of bounds during encoded read of an inline
extent
- only enforce free space tree if v1 cache is required
- print correct tree id in error message
* tag 'for-6.19-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: show correct warning if can't read data reloc tree
btrfs: fix NULL pointer dereference in do_abort_log_replay()
btrfs: force free space tree for bs > ps cases
btrfs: only enforce free space tree if v1 cache is required for bs < ps cases
btrfs: release path before initializing extent tree in btrfs_read_locked_inode()
btrfs: avoid access-beyond-folio for bs > ps encoded writes
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If a filesystem is missing its data reloc tree, we get something like
this in dmesg:
BTRFS warning (device loop11): failed to read root (objectid=4): -2
BTRFS error (device loop11): open_ctree failed: -2
objectid is BTRFS_DEV_TREE_OBJECTID, but this should actually be the
value of BTRFS_DATA_RELOC_TREE_OBJECTID.
btrfs_read_roots() prints location.objectid on failure, but this isn't
set when reading the data reloc tree. Set location.objectid to the
correct value on failure, so that the error message makes sense.
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Mark Harmstone <mark@harmstone.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Coverity reported a NULL pointer dereference issue (CID 1666756) in
do_abort_log_replay(). When btrfs_alloc_path() fails in
replay_one_buffer(), wc->subvol_path is NULL, but btrfs_abort_log_replay()
calls do_abort_log_replay() which unconditionally dereferences
wc->subvol_path when attempting to print debug information. Fix this by
adding a NULL check before dereferencing wc->subvol_path in
do_abort_log_replay().
Fixes: 2753e4917624 ("btrfs: dump detailed info and specific messages on log replay failures")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Suchit Karunakaran <suchitkarunakaran@gmail.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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[BUG]
Currently we only enforcing the free space tree for bs < ps cases, but
with the recently added bs > ps support, we lack the free space tree
enforcing, causing explicit v1 cache mount option to fail on bs > ps
cases:
# mount -o space_cache=v1 /dev/test/scratch1 /mnt/btrfs/
mount: /mnt/btrfs: wrong fs type, bad option, bad superblock on /dev/mapper/test-scratch1, missing codepage or helper program, or other error.
dmesg(1) may have more information after failed mount system call.
# dmesg -t | tail -n7
BTRFS: device fsid ac14a6fa-4ec9-449e-aec9-7d1777bfdc06 devid 1 transid 11 /dev/mapper/test-scratch1 (253:3) scanned by mount (2849)
BTRFS info (device dm-3): first mount of filesystem ac14a6fa-4ec9-449e-aec9-7d1777bfdc06
BTRFS info (device dm-3): using crc32c checksum algorithm
BTRFS warning (device dm-3): support for block size 8192 with page size 4096 is experimental, some features may be missing
BTRFS warning (device dm-3): space cache v1 is being deprecated and will be removed in a future release, please use -o space_cache=v2
BTRFS warning (device dm-3): v1 space cache is not supported for page size 4096 with sectorsize 8192
BTRFS error (device dm-3): open_ctree failed: -22
[FIX]
Just enable the same free space tree for bs > ps cases, aligning the
behavior to bs < ps cases.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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[BUG]
Since the introduction of btrfs bs < ps support, v1 cache was never on
the plan due to its hard coded PAGE_SIZE usage, and the future plan to
properly deprecate it.
However for bs < ps cases, even if 'nospace_cache,clear_cache' mount
option is specified, it's never respected and free space tree is always
enabled:
mkfs.btrfs -f -O ^bgt,fst $dev
mount $dev $mnt -o clear_cache,nospace_cache
umount $mnt
btrfs ins dump-super $dev
...
compat_ro_flags 0x3
( FREE_SPACE_TREE |
FREE_SPACE_TREE_VALID )
...
This means a different behavior compared to bs >= ps cases.
[CAUSE]
The forcing usage of v2 space cache is done inside
btrfs_set_free_space_cache_settings(), however it never checks if we're
even using space cache but always enabling v2 cache.
[FIX]
Instead unconditionally enable v2 cache, only forcing v2 cache if the
old v1 cache is required.
Now v2 space cache can be properly disabled on bs < ps cases:
mkfs.btrfs -f -O ^bgt,fst $dev
mount $dev $mnt -o clear_cache,nospace_cache
umount $mnt
btrfs ins dump-super $dev
...
compat_ro_flags 0x0
...
Fixes: 9f73f1aef98b ("btrfs: force v2 space cache usage for subpage mount")
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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In btrfs_read_locked_inode() we are calling btrfs_init_file_extent_tree()
while holding a path with a read locked leaf from a subvolume tree, and
btrfs_init_file_extent_tree() may do a GFP_KERNEL allocation, which can
trigger reclaim.
This can create a circular lock dependency which lockdep warns about with
the following splat:
[6.1433] ======================================================
[6.1574] WARNING: possible circular locking dependency detected
[6.1583] 6.18.0+ #4 Tainted: G U
[6.1591] ------------------------------------------------------
[6.1599] kswapd0/117 is trying to acquire lock:
[6.1606] ffff8d9b6333c5b8 (&delayed_node->mutex){+.+.}-{3:3}, at: __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1625]
but task is already holding lock:
[6.1633] ffffffffa4ab8ce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x195/0xc60
[6.1646]
which lock already depends on the new lock.
[6.1657]
the existing dependency chain (in reverse order) is:
[6.1667]
-> #2 (fs_reclaim){+.+.}-{0:0}:
[6.1677] fs_reclaim_acquire+0x9d/0xd0
[6.1685] __kmalloc_cache_noprof+0x59/0x750
[6.1694] btrfs_init_file_extent_tree+0x90/0x100
[6.1702] btrfs_read_locked_inode+0xc3/0x6b0
[6.1710] btrfs_iget+0xbb/0xf0
[6.1716] btrfs_lookup_dentry+0x3c5/0x8e0
[6.1724] btrfs_lookup+0x12/0x30
[6.1731] lookup_open.isra.0+0x1aa/0x6a0
[6.1739] path_openat+0x5f7/0xc60
[6.1746] do_filp_open+0xd6/0x180
[6.1753] do_sys_openat2+0x8b/0xe0
[6.1760] __x64_sys_openat+0x54/0xa0
[6.1768] do_syscall_64+0x97/0x3e0
[6.1776] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[6.1784]
-> #1 (btrfs-tree-00){++++}-{3:3}:
[6.1794] lock_release+0x127/0x2a0
[6.1801] up_read+0x1b/0x30
[6.1808] btrfs_search_slot+0x8e0/0xff0
[6.1817] btrfs_lookup_inode+0x52/0xd0
[6.1825] __btrfs_update_delayed_inode+0x73/0x520
[6.1833] btrfs_commit_inode_delayed_inode+0x11a/0x120
[6.1842] btrfs_log_inode+0x608/0x1aa0
[6.1849] btrfs_log_inode_parent+0x249/0xf80
[6.1857] btrfs_log_dentry_safe+0x3e/0x60
[6.1865] btrfs_sync_file+0x431/0x690
[6.1872] do_fsync+0x39/0x80
[6.1879] __x64_sys_fsync+0x13/0x20
[6.1887] do_syscall_64+0x97/0x3e0
[6.1894] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[6.1903]
-> #0 (&delayed_node->mutex){+.+.}-{3:3}:
[6.1913] __lock_acquire+0x15e9/0x2820
[6.1920] lock_acquire+0xc9/0x2d0
[6.1927] __mutex_lock+0xcc/0x10a0
[6.1934] __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1944] btrfs_evict_inode+0x20b/0x4b0
[6.1952] evict+0x15a/0x2f0
[6.1958] prune_icache_sb+0x91/0xd0
[6.1966] super_cache_scan+0x150/0x1d0
[6.1974] do_shrink_slab+0x155/0x6f0
[6.1981] shrink_slab+0x48e/0x890
[6.1988] shrink_one+0x11a/0x1f0
[6.1995] shrink_node+0xbfd/0x1320
[6.1002] balance_pgdat+0x67f/0xc60
[6.1321] kswapd+0x1dc/0x3e0
[6.1643] kthread+0xff/0x240
[6.1965] ret_from_fork+0x223/0x280
[6.1287] ret_from_fork_asm+0x1a/0x30
[6.1616]
other info that might help us debug this:
[6.1561] Chain exists of:
&delayed_node->mutex --> btrfs-tree-00 --> fs_reclaim
[6.1503] Possible unsafe locking scenario:
[6.1110] CPU0 CPU1
[6.1411] ---- ----
[6.1707] lock(fs_reclaim);
[6.1998] lock(btrfs-tree-00);
[6.1291] lock(fs_reclaim);
[6.1581] lock(&delayed_node->mutex);
[6.1874]
*** DEADLOCK ***
[6.1716] 2 locks held by kswapd0/117:
[6.1999] #0: ffffffffa4ab8ce0 (fs_reclaim){+.+.}-{0:0}, at: balance_pgdat+0x195/0xc60
[6.1294] #1: ffff8d998344b0e0 (&type->s_umount_key#40){++++}- {3:3}, at: super_cache_scan+0x37/0x1d0
[6.1596]
stack backtrace:
[6.1183] CPU: 11 UID: 0 PID: 117 Comm: kswapd0 Tainted: G U 6.18.0+ #4 PREEMPT(lazy)
[6.1185] Tainted: [U]=USER
[6.1186] Hardware name: ASUS System Product Name/PRIME B560M-A AC, BIOS 2001 02/01/2023
[6.1187] Call Trace:
[6.1187] <TASK>
[6.1189] dump_stack_lvl+0x6e/0xa0
[6.1192] print_circular_bug.cold+0x17a/0x1c0
[6.1194] check_noncircular+0x175/0x190
[6.1197] __lock_acquire+0x15e9/0x2820
[6.1200] lock_acquire+0xc9/0x2d0
[6.1201] ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1204] __mutex_lock+0xcc/0x10a0
[6.1206] ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1208] ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1211] ? __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1213] __btrfs_release_delayed_node.part.0+0x39/0x2f0
[6.1215] btrfs_evict_inode+0x20b/0x4b0
[6.1217] ? lock_acquire+0xc9/0x2d0
[6.1220] evict+0x15a/0x2f0
[6.1222] prune_icache_sb+0x91/0xd0
[6.1224] super_cache_scan+0x150/0x1d0
[6.1226] do_shrink_slab+0x155/0x6f0
[6.1228] shrink_slab+0x48e/0x890
[6.1229] ? shrink_slab+0x2d2/0x890
[6.1231] shrink_one+0x11a/0x1f0
[6.1234] shrink_node+0xbfd/0x1320
[6.1236] ? shrink_node+0xa2d/0x1320
[6.1236] ? shrink_node+0xbd3/0x1320
[6.1239] ? balance_pgdat+0x67f/0xc60
[6.1239] balance_pgdat+0x67f/0xc60
[6.1241] ? finish_task_switch.isra.0+0xc4/0x2a0
[6.1246] kswapd+0x1dc/0x3e0
[6.1247] ? __pfx_autoremove_wake_function+0x10/0x10
[6.1249] ? __pfx_kswapd+0x10/0x10
[6.1250] kthread+0xff/0x240
[6.1251] ? __pfx_kthread+0x10/0x10
[6.1253] ret_from_fork+0x223/0x280
[6.1255] ? __pfx_kthread+0x10/0x10
[6.1257] ret_from_fork_asm+0x1a/0x30
[6.1260] </TASK>
This is because:
1) The fsync task is holding an inode's delayed node mutex (for a
directory) while calling __btrfs_update_delayed_inode() and that needs
to do a search on the subvolume's btree (therefore read lock some
extent buffers);
2) The lookup task, at btrfs_lookup(), triggered reclaim with the
GFP_KERNEL allocation done by btrfs_init_file_extent_tree() while
holding a read lock on a subvolume leaf;
3) The reclaim triggered kswapd which is doing inode eviction for the
directory inode the fsync task is using as an argument to
btrfs_commit_inode_delayed_inode() - but in that call chain we are
trying to read lock the same leaf that the lookup task is holding
while calling btrfs_init_file_extent_tree() and doing the GFP_KERNEL
allocation.
Fix this by calling btrfs_init_file_extent_tree() after we don't need the
path anymore and release it in btrfs_read_locked_inode().
Reported-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Link: https://lore.kernel.org/linux-btrfs/6e55113a22347c3925458a5d840a18401a38b276.camel@linux.intel.com/
Fixes: 8679d2687c35 ("btrfs: initialize inode::file_extent_tree after i_mode has been set")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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[POTENTIAL BUG]
If the system page size is 4K and fs block size is 8K, and max_inline
mount option is set to 6K, we can inline a 6K sized data extent.
Then a encoded write submitted a compressed extent which is at file
offset 0, and the compressed length is 6K, which is allowed to be inlined.
Now a read beyond page boundary is triggered inside write_extent_buffer()
from insert_inline_extent().
[CAUSE]
Currently the function __cow_file_range_inline() can only accept a
single folio.
For regular compressed write path, we always allocate the compressed
folios using the minimal order matching the block size, thus the
@compressed_folio should always cover a full fs block thus it is fine.
But for encoded writes, they allocate page size folios, this means we
can hit a case where the compressed data is smaller than block size but
still larger than page size, in that case __cow_file_range_inline() will
be called with @compressed_size larger than a page.
In that case we will trigger a read beyond the folio inside
insert_inline_extent().
Thankfully this is not that common, as the default max_inline is only
2048 bytes, smaller than PAGE_SIZE, and bs > ps support is still
experimental.
[FIX]
We need to either allow insert_inline_extent() to accept a page array to
properly support such case, or reject such inline extent.
The latter is a much simpler solution, and considering bs > ps will stay
as a corner case and non-default max_inline will be even rarer, I don't
think we really need to fulfill such niche.
So just reject any inline extent that's larger than PAGE_SIZE, and add
an extra ASSERT() to insert_inline_extent() to catch such beyond-boundary
access.
Fixes: ec20799064c8 ("btrfs: enable encoded read/write/send for bs > ps cases")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- fix potential deadlock due to mismatching transaction states when
waiting for the current transaction
- fix squota accounting with nested snapshots
- fix quota inheritance of qgroups with multiple parent qgroups
- fix NULL inode pointer in evict tracepoint
- fix writes beyond end of file on systems with 64K page size and 4K
block size
- fix logging of inodes after exchange rename
- fix use after free when using ref_tracker feature
- space reservation fixes
* tag 'for-6.19-rc4-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix reservation leak in some error paths when inserting inline extent
btrfs: do not free data reservation in fallback from inline due to -ENOSPC
btrfs: fix use-after-free warning in btrfs_get_or_create_delayed_node()
btrfs: always detect conflicting inodes when logging inode refs
btrfs: fix beyond-EOF write handling
btrfs: fix deadlock in wait_current_trans() due to ignored transaction type
btrfs: fix NULL dereference on root when tracing inode eviction
btrfs: qgroup: update all parent qgroups when doing quick inherit
btrfs: fix qgroup_snapshot_quick_inherit() squota bug
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If we fail to allocate a path or join a transaction, we return from
__cow_file_range_inline() without freeing the reserved qgroup data,
resulting in a leak. Fix this by ensuring we call btrfs_qgroup_free_data()
in such cases.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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If we fail to create an inline extent due to -ENOSPC, we will attempt to
go through the normal COW path, reserve an extent, create an ordered
extent, etc. However we were always freeing the reserved qgroup data,
which is wrong since we will use data. Fix this by freeing the reserved
qgroup data in __cow_file_range_inline() only if we are not doing the
fallback (ret is <= 0).
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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Previously, btrfs_get_or_create_delayed_node() set the delayed_node's
refcount before acquiring the root->delayed_nodes lock.
Commit e8513c012de7 ("btrfs: implement ref_tracker for delayed_nodes")
moved refcount_set inside the critical section, which means there is
no longer a memory barrier between setting the refcount and setting
btrfs_inode->delayed_node.
Without that barrier, the stores to node->refs and
btrfs_inode->delayed_node may become visible out of order. Another
thread can then read btrfs_inode->delayed_node and attempt to
increment a refcount that hasn't been set yet, leading to a
refcounting bug and a use-after-free warning.
The fix is to move refcount_set back to where it was to take
advantage of the implicit memory barrier provided by lock
acquisition.
Because the allocations now happen outside of the lock's critical
section, they can use GFP_NOFS instead of GFP_ATOMIC.
Reported-by: kernel test robot <oliver.sang@intel.com>
Closes: https://lore.kernel.org/oe-lkp/202511262228.6dda231e-lkp@intel.com
Fixes: e8513c012de7 ("btrfs: implement ref_tracker for delayed_nodes")
Tested-by: kernel test robot <oliver.sang@intel.com>
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Leo Martins <loemra.dev@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.com>
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After rename exchanging (either with the rename exchange operation or
regular renames in multiple non-atomic steps) two inodes and at least
one of them is a directory, we can end up with a log tree that contains
only of the inodes and after a power failure that can result in an attempt
to delete the other inode when it should not because it was not deleted
before the power failure. In some case that delete attempt fails when
the target inode is a directory that contains a subvolume inside it, since
the log replay code is not prepared to deal with directory entries that
point to root items (only inode items).
1) We have directories "dir1" (inode A) and "dir2" (inode B) under the
same parent directory;
2) We have a file (inode C) under directory "dir1" (inode A);
3) We have a subvolume inside directory "dir2" (inode B);
4) All these inodes were persisted in a past transaction and we are
currently at transaction N;
5) We rename the file (inode C), so at btrfs_log_new_name() we update
inode C's last_unlink_trans to N;
6) We get a rename exchange for "dir1" (inode A) and "dir2" (inode B),
so after the exchange "dir1" is inode B and "dir2" is inode A.
During the rename exchange we call btrfs_log_new_name() for inodes
A and B, but because they are directories, we don't update their
last_unlink_trans to N;
7) An fsync against the file (inode C) is done, and because its inode
has a last_unlink_trans with a value of N we log its parent directory
(inode A) (through btrfs_log_all_parents(), called from
btrfs_log_inode_parent()).
8) So we end up with inode B not logged, which now has the old name
of inode A. At copy_inode_items_to_log(), when logging inode A, we
did not check if we had any conflicting inode to log because inode
A has a generation lower than the current transaction (created in
a past transaction);
9) After a power failure, when replaying the log tree, since we find that
inode A has a new name that conflicts with the name of inode B in the
fs tree, we attempt to delete inode B... this is wrong since that
directory was never deleted before the power failure, and because there
is a subvolume inside that directory, attempting to delete it will fail
since replay_dir_deletes() and btrfs_unlink_inode() are not prepared
to deal with dir items that point to roots instead of inodes.
When that happens the mount fails and we get a stack trace like the
following:
[87.2314] BTRFS info (device dm-0): start tree-log replay
[87.2318] BTRFS critical (device dm-0): failed to delete reference to subvol, root 5 inode 256 parent 259
[87.2332] ------------[ cut here ]------------
[87.2338] BTRFS: Transaction aborted (error -2)
[87.2346] WARNING: CPU: 1 PID: 638968 at fs/btrfs/inode.c:4345 __btrfs_unlink_inode+0x416/0x440 [btrfs]
[87.2368] Modules linked in: btrfs loop dm_thin_pool (...)
[87.2470] CPU: 1 UID: 0 PID: 638968 Comm: mount Tainted: G W 6.18.0-rc7-btrfs-next-218+ #2 PREEMPT(full)
[87.2489] Tainted: [W]=WARN
[87.2494] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014
[87.2514] RIP: 0010:__btrfs_unlink_inode+0x416/0x440 [btrfs]
[87.2538] Code: c0 89 04 24 (...)
[87.2568] RSP: 0018:ffffc0e741f4b9b8 EFLAGS: 00010286
[87.2574] RAX: 0000000000000000 RBX: ffff9d3ec8a6cf60 RCX: 0000000000000000
[87.2582] RDX: 0000000000000002 RSI: ffffffff84ab45a1 RDI: 00000000ffffffff
[87.2591] RBP: ffff9d3ec8a6ef20 R08: 0000000000000000 R09: ffffc0e741f4b840
[87.2599] R10: ffff9d45dc1fffa8 R11: 0000000000000003 R12: ffff9d3ee26d77e0
[87.2608] R13: ffffc0e741f4ba98 R14: ffff9d4458040800 R15: ffff9d44b6b7ca10
[87.2618] FS: 00007f7b9603a840(0000) GS:ffff9d4658982000(0000) knlGS:0000000000000000
[87.2629] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[87.2637] CR2: 00007ffc9ec33b98 CR3: 000000011273e003 CR4: 0000000000370ef0
[87.2648] Call Trace:
[87.2651] <TASK>
[87.2654] btrfs_unlink_inode+0x15/0x40 [btrfs]
[87.2661] unlink_inode_for_log_replay+0x27/0xf0 [btrfs]
[87.2669] check_item_in_log+0x1ea/0x2c0 [btrfs]
[87.2676] replay_dir_deletes+0x16b/0x380 [btrfs]
[87.2684] fixup_inode_link_count+0x34b/0x370 [btrfs]
[87.2696] fixup_inode_link_counts+0x41/0x160 [btrfs]
[87.2703] btrfs_recover_log_trees+0x1ff/0x7c0 [btrfs]
[87.2711] ? __pfx_replay_one_buffer+0x10/0x10 [btrfs]
[87.2719] open_ctree+0x10bb/0x15f0 [btrfs]
[87.2726] btrfs_get_tree.cold+0xb/0x16c [btrfs]
[87.2734] ? fscontext_read+0x15c/0x180
[87.2740] ? rw_verify_area+0x50/0x180
[87.2746] vfs_get_tree+0x25/0xd0
[87.2750] vfs_cmd_create+0x59/0xe0
[87.2755] __do_sys_fsconfig+0x4f6/0x6b0
[87.2760] do_syscall_64+0x50/0x1220
[87.2764] entry_SYSCALL_64_after_hwframe+0x76/0x7e
[87.2770] RIP: 0033:0x7f7b9625f4aa
[87.2775] Code: 73 01 c3 48 (...)
[87.2803] RSP: 002b:00007ffc9ec35b08 EFLAGS: 00000246 ORIG_RAX: 00000000000001af
[87.2817] RAX: ffffffffffffffda RBX: 0000558bfa91ac20 RCX: 00007f7b9625f4aa
[87.2829] RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003
[87.2842] RBP: 0000558bfa91b120 R08: 0000000000000000 R09: 0000000000000000
[87.2854] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
[87.2864] R13: 00007f7b963f1580 R14: 00007f7b963f326c R15: 00007f7b963d8a23
[87.2877] </TASK>
[87.2882] ---[ end trace 0000000000000000 ]---
[87.2891] BTRFS: error (device dm-0 state A) in __btrfs_unlink_inode:4345: errno=-2 No such entry
[87.2904] BTRFS: error (device dm-0 state EAO) in do_abort_log_replay:191: errno=-2 No such entry
[87.2915] BTRFS critical (device dm-0 state EAO): log tree (for root 5) leaf currently being processed (slot 7 key (258 12 257)):
[87.2929] BTRFS info (device dm-0 state EAO): leaf 30736384 gen 10 total ptrs 7 free space 15712 owner 18446744073709551610
[87.2929] BTRFS info (device dm-0 state EAO): refs 3 lock_owner 0 current 638968
[87.2929] item 0 key (257 INODE_ITEM 0) itemoff 16123 itemsize 160
[87.2929] inode generation 9 transid 10 size 0 nbytes 0
[87.2929] block group 0 mode 40755 links 1 uid 0 gid 0
[87.2929] rdev 0 sequence 7 flags 0x0
[87.2929] atime 1765464494.678070921
[87.2929] ctime 1765464494.686606513
[87.2929] mtime 1765464494.686606513
[87.2929] otime 1765464494.678070921
[87.2929] item 1 key (257 INODE_REF 256) itemoff 16109 itemsize 14
[87.2929] index 4 name_len 4
[87.2929] item 2 key (257 DIR_LOG_INDEX 2) itemoff 16101 itemsize 8
[87.2929] dir log end 2
[87.2929] item 3 key (257 DIR_LOG_INDEX 3) itemoff 16093 itemsize 8
[87.2929] dir log end 18446744073709551615
[87.2930] item 4 key (257 DIR_INDEX 3) itemoff 16060 itemsize 33
[87.2930] location key (258 1 0) type 1
[87.2930] transid 10 data_len 0 name_len 3
[87.2930] item 5 key (258 INODE_ITEM 0) itemoff 15900 itemsize 160
[87.2930] inode generation 9 transid 10 size 0 nbytes 0
[87.2930] block group 0 mode 100644 links 1 uid 0 gid 0
[87.2930] rdev 0 sequence 2 flags 0x0
[87.2930] atime 1765464494.678456467
[87.2930] ctime 1765464494.686606513
[87.2930] mtime 1765464494.678456467
[87.2930] otime 1765464494.678456467
[87.2930] item 6 key (258 INODE_REF 257) itemoff 15887 itemsize 13
[87.2930] index 3 name_len 3
[87.2930] BTRFS critical (device dm-0 state EAO): log replay failed in unlink_inode_for_log_replay:1045 for root 5, stage 3, with error -2: failed to unlink inode 256 parent dir 259 name subvol root 5
[87.2963] BTRFS: error (device dm-0 state EAO) in btrfs_recover_log_trees:7743: errno=-2 No such entry
[87.2981] BTRFS: error (device dm-0 state EAO) in btrfs_replay_log:2083: errno=-2 No such entry (Failed to recover log tr
So fix this by changing copy_inode_items_to_log() to always detect if
there are conflicting inodes for the ref/extref of the inode being logged
even if the inode was created in a past transaction.
A test case for fstests will follow soon.
CC: stable@vger.kernel.org # 6.1+
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
[BUG]
For the following write sequence with 64K page size and 4K fs block size,
it will lead to file extent items to be inserted without any data
checksum:
mkfs.btrfs -s 4k -f $dev > /dev/null
mount $dev $mnt
xfs_io -f -c "pwrite 0 16k" -c "pwrite 32k 4k" -c pwrite "60k 64K" \
-c "truncate 16k" $mnt/foobar
umount $mnt
This will result the following 2 file extent items to be inserted (extra
trace point added to insert_ordered_extent_file_extent()):
btrfs_finish_one_ordered: root=5 ino=257 file_off=61440 num_bytes=4096 csum_bytes=0
btrfs_finish_one_ordered: root=5 ino=257 file_off=0 num_bytes=16384 csum_bytes=16384
Note for file offset 60K, we're inserting a file extent without any
data checksum.
Also note that range [32K, 36K) didn't reach
insert_ordered_extent_file_extent(), which is the correct behavior as
that OE is fully truncated, should not result any file extent.
Although file extent at 60K will be later dropped by btrfs_truncate(),
if the transaction got committed after file extent inserted but before
the file extent dropping, we will have a small window where we have a
file extent beyond EOF and without any data checksum.
That will cause "btrfs check" to report error.
[CAUSE]
The sequence happens like this:
- Buffered write dirtied the page cache and updated isize
Now the inode size is 64K, with the following page cache layout:
0 16K 32K 48K 64K
|/////////////| |//| |//|
- Truncate the inode to 16K
Which will trigger writeback through:
btrfs_setsize()
|- truncate_setsize()
| Now the inode size is set to 16K
|
|- btrfs_truncate()
|- btrfs_wait_ordered_range() for [16K, u64(-1)]
|- btrfs_fdatawrite_range() for [16K, u64(-1)}
|- extent_writepage() for folio 0
|- writepage_delalloc()
| Generated OE for [0, 16K), [32K, 36K] and [60K, 64K)
|
|- extent_writepage_io()
Then inside extent_writepage_io(), the dirty fs blocks are handled
differently:
- Submit write for range [0, 16K)
As they are still inside the inode size (16K).
- Mark OE [32K, 36K) as truncated
Since we only call btrfs_lookup_first_ordered_range() once, which
returned the first OE after file offset 16K.
- Mark all OEs inside range [16K, 64K) as finished
Which will mark OE ranges [32K, 36K) and [60K, 64K) as finished.
For OE [32K, 36K) since it's already marked as truncated, and its
truncated length is 0, no file extent will be inserted.
For OE [60K, 64K) it has never been submitted thus has no data
checksum, and we insert the file extent as usual.
This is the root cause of file extent at 60K to be inserted without
any data checksum.
- Clear dirty flags for range [16K, 64K)
It is the function btrfs_folio_clear_dirty() which searches and clears
any dirty blocks inside that range.
[FIX]
The bug itself was introduced a long time ago, way before subpage and
large folio support.
At that time, fs block size must match page size, thus the range
[cur, end) is just one fs block.
But later with subpage and large folios, the same range [cur, end)
can have multiple blocks and ordered extents.
Later commit 18de34daa7c6 ("btrfs: truncate ordered extent when skipping
writeback past i_size") was fixing a bug related to subpage/large
folios, but it's still utilizing the old range [cur, end), meaning only
the first OE will be marked as truncated.
The proper fix here is to make EOF handling block-by-block, not trying
to handle the whole range to @end.
By this we always locate and truncate the OE for every dirty block.
CC: stable@vger.kernel.org # 5.15+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
When wait_current_trans() is called during start_transaction(), it
currently waits for a blocked transaction without considering whether
the given transaction type actually needs to wait for that particular
transaction state. The btrfs_blocked_trans_types[] array already defines
which transaction types should wait for which transaction states, but
this check was missing in wait_current_trans().
This can lead to a deadlock scenario involving two transactions and
pending ordered extents:
1. Transaction A is in TRANS_STATE_COMMIT_DOING state
2. A worker processing an ordered extent calls start_transaction()
with TRANS_JOIN
3. join_transaction() returns -EBUSY because Transaction A is in
TRANS_STATE_COMMIT_DOING
4. Transaction A moves to TRANS_STATE_UNBLOCKED and completes
5. A new Transaction B is created (TRANS_STATE_RUNNING)
6. The ordered extent from step 2 is added to Transaction B's
pending ordered extents
7. Transaction B immediately starts commit by another task and
enters TRANS_STATE_COMMIT_START
8. The worker finally reaches wait_current_trans(), sees Transaction B
in TRANS_STATE_COMMIT_START (a blocked state), and waits
unconditionally
9. However, TRANS_JOIN should NOT wait for TRANS_STATE_COMMIT_START
according to btrfs_blocked_trans_types[]
10. Transaction B is waiting for pending ordered extents to complete
11. Deadlock: Transaction B waits for ordered extent, ordered extent
waits for Transaction B
This can be illustrated by the following call stacks:
CPU0 CPU1
btrfs_finish_ordered_io()
start_transaction(TRANS_JOIN)
join_transaction()
# -EBUSY (Transaction A is
# TRANS_STATE_COMMIT_DOING)
# Transaction A completes
# Transaction B created
# ordered extent added to
# Transaction B's pending list
btrfs_commit_transaction()
# Transaction B enters
# TRANS_STATE_COMMIT_START
# waiting for pending ordered
# extents
wait_current_trans()
# waits for Transaction B
# (should not wait!)
Task bstore_kv_sync in btrfs_commit_transaction waiting for ordered
extents:
__schedule+0x2e7/0x8a0
schedule+0x64/0xe0
btrfs_commit_transaction+0xbf7/0xda0 [btrfs]
btrfs_sync_file+0x342/0x4d0 [btrfs]
__x64_sys_fdatasync+0x4b/0x80
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Task kworker in wait_current_trans waiting for transaction commit:
Workqueue: btrfs-syno_nocow btrfs_work_helper [btrfs]
__schedule+0x2e7/0x8a0
schedule+0x64/0xe0
wait_current_trans+0xb0/0x110 [btrfs]
start_transaction+0x346/0x5b0 [btrfs]
btrfs_finish_ordered_io.isra.0+0x49b/0x9c0 [btrfs]
btrfs_work_helper+0xe8/0x350 [btrfs]
process_one_work+0x1d3/0x3c0
worker_thread+0x4d/0x3e0
kthread+0x12d/0x150
ret_from_fork+0x1f/0x30
Fix this by passing the transaction type to wait_current_trans() and
checking btrfs_blocked_trans_types[cur_trans->state] against the given
type before deciding to wait. This ensures that transaction types which
are allowed to join during certain blocked states will not unnecessarily
wait and cause deadlocks.
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Robbie Ko <robbieko@synology.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
[BUG]
There is a bug that if a subvolume has multi-level parent qgroups, and
is able to do a quick inherit, only the direct parent qgroup got
updated:
mkfs.btrfs -f -O quota $dev
mount $dev $mnt
btrfs subv create $mnt/subv1
btrfs qgroup create 1/100 $mnt
btrfs qgroup create 2/100 $mnt
btrfs qgroup assign 1/100 2/100 $mnt
btrfs qgroup assign 0/256 1/100 $mnt
btrfs qgroup show -p --sync $mnt
Qgroupid Referenced Exclusive Parent Path
-------- ---------- --------- ------ ----
0/5 16.00KiB 16.00KiB - <toplevel>
0/256 16.00KiB 16.00KiB 1/100 subv1
1/100 16.00KiB 16.00KiB 2/100 2/100<1 member qgroup>
2/100 16.00KiB 16.00KiB - <0 member qgroups>
btrfs subv snap -i 1/100 $mnt/subv1 $mnt/snap1
btrfs qgroup show -p --sync $mnt
Qgroupid Referenced Exclusive Parent Path
-------- ---------- --------- ------ ----
0/5 16.00KiB 16.00KiB - <toplevel>
0/256 16.00KiB 16.00KiB 1/100 subv1
0/257 16.00KiB 16.00KiB 1/100 snap1
1/100 32.00KiB 32.00KiB 2/100 2/100<1 member qgroup>
2/100 16.00KiB 16.00KiB - <0 member qgroups>
# Note that 2/100 is not updated, and qgroup numbers are inconsistent
umount $mnt
[CAUSE]
If the snapshot source subvolume belongs to a parent qgroup, and the new
snapshot target is also added to the new same parent qgroup, we allow a
quick update without marking qgroup inconsistent.
But that quick update only update the parent qgroup, without checking if
there is any more parent qgroups.
[FIX]
Iterate through all parent qgroups during the quick inherit.
Reported-by: Boris Burkov <boris@bur.io>
Fixes: b20fe56cd285 ("btrfs: qgroup: allow quick inherit if snapshot is created and added to the same parent")
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
qgroup_snapshot_quick_inherit() detects conditions where the snapshot
destination would land in the same parent qgroup as the snapshot source
subvolume. In this case we can avoid costly qgroup calculations and just
add the nodesize of the new snapshot to the parent.
However, in the case of squotas this is actually a double count, and
also an undercount for deeper qgroup nestings.
The following annotated script shows the issue:
btrfs quota enable --simple "$mnt"
# Create 2-level qgroup hierarchy
btrfs qgroup create 2/100 "$mnt" # Q2 (level 2)
btrfs qgroup create 1/100 "$mnt" # Q1 (level 1)
btrfs qgroup assign 1/100 2/100 "$mnt"
# Create base subvolume
btrfs subvolume create "$mnt/base" >/dev/null
base_id=$(btrfs subvolume show "$mnt/base" | grep 'Subvolume ID:' | awk '{print $3}')
# Create intermediate snapshot and add to Q1
btrfs subvolume snapshot "$mnt/base" "$mnt/intermediate" >/dev/null
inter_id=$(btrfs subvolume show "$mnt/intermediate" | grep 'Subvolume ID:' | awk '{print $3}')
btrfs qgroup assign "0/$inter_id" 1/100 "$mnt"
# Create working snapshot with --inherit (auto-adds to Q1)
# src=intermediate (in only Q1)
# dst=snap (inheriting only into Q1)
# This double counts the 16k nodesize of the snapshot in Q1, and
# undercounts it in Q2.
btrfs subvolume snapshot -i 1/100 "$mnt/intermediate" "$mnt/snap" >/dev/null
snap_id=$(btrfs subvolume show "$mnt/snap" | grep 'Subvolume ID:' | awk '{print $3}')
# Fully complete snapshot creation
sync
# Delete working snapshot
# Q1 and Q2 will lose the full snap usage
btrfs subvolume delete "$mnt/snap" >/dev/null
# Delete intermediate and remove from Q1
# Q1 and Q2 will lose the full intermediate usage
btrfs qgroup remove "0/$inter_id" 1/100 "$mnt"
btrfs subvolume delete "$mnt/intermediate" >/dev/null
# Q1 should be at 0, but still has 16k. Q2 is "correct" at 0 (for now...)
# Trigger cleaner, wait for deletions
mount -o remount,sync=1 "$mnt"
btrfs subvolume sync "$mnt" "$snap_id"
btrfs subvolume sync "$mnt" "$inter_id"
# Remove Q1 from Q2
# Frees 16k more from Q2, underflowing it to 16EiB
btrfs qgroup remove 1/100 2/100 "$mnt"
# And show the bad state:
btrfs qgroup show -pc "$mnt"
Qgroupid Referenced Exclusive Parent Child Path
-------- ---------- --------- ------ ----- ----
0/5 16.00KiB 16.00KiB - - <toplevel>
0/256 16.00KiB 16.00KiB - - base
1/100 16.00KiB 16.00KiB - - <0 member qgroups>
2/100 16.00EiB 16.00EiB - - <0 member qgroups>
Fix this by simply not doing this quick inheritance with squotas.
I suspect that it is also wrong in normal qgroups to not recurse up the
qgroup tree in the quick inherit case, though other consistency checks
will likely fix it anyway.
Fixes: b20fe56cd285 ("btrfs: qgroup: allow quick inherit if snapshot is created and added to the same parent")
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux
Pull btrfs fixes from David Sterba:
- fix missing btrfs_path release after printing a relocation error
message
- fix extent changeset leak on mmap write after failure to reserve
metadata
- fix fs devices list structure freeing, it could be potentially leaked
under some circumstances
- tree log fixes:
- fix incremental directory logging where inodes for new dentries
were incorrectly skipped
- don't log conflicting inode if it's a directory moved in the
current transaction
- regression fixes:
- fix incorrect btrfs_path freeing when it's auto-cleaned
- revert commit simplifying preallocation of temporary structures
in qgroup functions, some cases were not handled properly
* tag 'for-6.19-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
btrfs: fix changeset leak on mmap write after failure to reserve metadata
btrfs: fix memory leak of fs_devices in degraded seed device path
btrfs: fix a potential path leak in print_data_reloc_error()
Revert "btrfs: add ASSERTs on prealloc in qgroup functions"
btrfs: do not skip logging new dentries when logging a new name
btrfs: don't log conflicting inode if it's a dir moved in the current transaction
btrfs: tests: fix double btrfs_path free in remove_extent_ref()
|
|
If the call to btrfs_delalloc_reserve_metadata() fails we jump to the
'out_noreserve' label and there we never free the extent_changeset
allocated by the previous call to btrfs_check_data_free_space() (if
qgroups are enabled). Fix this by calling extent_changeset_free() under
the 'out_noreserve' label.
Fixes: 6599716de2d6 ("btrfs: fix -ENOSPC mmap write failure on NOCOW files/extents")
Reported-by: syzbot+2f8aa76e6acc9fce6638@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/693a635a.a70a0220.33cd7b.0029.GAE@google.com/
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
In open_seed_devices(), when find_fsid() fails and we're in DEGRADED
mode, a new fs_devices is allocated via alloc_fs_devices() but is never
added to the seed_list before returning. This contrasts with the normal
path where fs_devices is properly added via list_add().
If any error occurs later in read_one_dev() or btrfs_read_chunk_tree(),
the cleanup code iterates seed_list to free seed devices, but this
orphaned fs_devices is never found and never freed, causing a memory
leak. Any devices allocated via add_missing_dev() and attached to this
fs_devices are also leaked.
Fix this by adding the newly allocated fs_devices to seed_list in the
degraded path, consistent with the normal path.
Fixes: 5f37583569442 ("Btrfs: move the missing device to its own fs device list")
Reported-by: syzbot+eadd98df8bceb15d7fed@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=eadd98df8bceb15d7fed
Tested-by: syzbot+eadd98df8bceb15d7fed@syzkaller.appspotmail.com
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Deepanshu Kartikey <kartikey406@gmail.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
Inside print_data_reloc_error(), if extent_from_logical() failed we
return immediately.
However there are the following cases where extent_from_logical() can
return error but still holds a path:
- btrfs_search_slot() returned 0
- No backref item found in extent tree
- No flags_ret provided
This is not possible in this call site though.
So for the above two cases, we can return without releasing the path,
causing extent buffer leaks.
Fixes: b9a9a85059cd ("btrfs: output affected files when relocation fails")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
This reverts commit 252877a8701530fde861a4f27710c1e718e97caa.
Commit 252877a87015 ("btrfs: add ASSERTs on prealloc in qgroup
functions") tries to remove the kfree() on preallocated qgroup during
several call sites, but this cannot work as intended:
- btrfs_quota_enable()
- btrfs_create_qgroup()
If add_qgroup_item() failed, we go out_free_path() and at that time
prealloc is not yet utilized and will trigger the new ASSERT().
- btrfs_qgroup_inherit()
If qgroup_auto_inherit() failed, prealloc is not yet utilized and
will trigger the new ASSERT()
Reported-by: syzbot+b44d4a4885bc82af2a06@syzkaller.appspotmail.com
Link: https://lore.kernel.org/linux-btrfs/69369331.a70a0220.38f243.009e.GAE@google.com/
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
When we are logging a directory and the log context indicates that we
are logging a new name for some other file (that is or was inside that
directory), we skip logging the inodes for new dentries in the directory.
This is ok most of the time, but if after the rename or link operation
that triggered the logging of that directory, we have an explicit fsync
of that directory without the directory inode being evicted and reloaded,
we end up never logging the inodes for the new dentries that we found
during the new name logging, as the next directory fsync will only process
dentries that were added after the last time we logged the directory (we
are doing an incremental directory logging).
So make sure we always log new dentries for a directory even if we are
in a context of logging a new name.
We started skipping logging inodes for new dentries as of commit
c48792c6ee7a ("btrfs: do not log new dentries when logging that a new name
exists") and it was fine back then, because when logging a directory we
always iterated over all the directory entries (for leaves changed in the
current transaction) so a subsequent fsync would always log anything that
was previously skipped while logging a directory when logging a new name
(with btrfs_log_new_name()). But later support for incrementally logging
a directory was added in commit dc2872247ec0 ("btrfs: keep track of the
last logged keys when logging a directory"), to avoid checking all dir
items every time we log a directory, so the check to skip dentry logging
added in the first commit should have been removed when the incremental
support for logging a directory was added.
A test case for fstests will follow soon.
Reported-by: Vyacheslav Kovalevsky <slava.kovalevskiy.2014@gmail.com>
Link: https://lore.kernel.org/linux-btrfs/84c4e713-85d6-42b9-8dcf-0722ed26cb05@gmail.com/
Fixes: dc2872247ec0 ("btrfs: keep track of the last logged keys when logging a directory")
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
|
|
transaction
We can't log a conflicting inode if it's a directory and it was moved
from one parent directory to another parent directory in the current
transaction, as this can result an attempt to have a directory with
two hard links during log replay, one for the old parent directory and
another for the new parent directory.
The following scenario triggers that issue:
1) We have directories "dir1" and "dir2" created in a past transaction.
Directory "dir1" has inode A as its parent directory;
2) We move "dir1" to some other directory;
3) We create a file with the name "dir1" in directory inode A;
4) We fsync the new file. This results in logging the inode of the new file
and the inode for the directory "dir1" that was previously moved in the
current transaction. So the log tree has the INODE_REF item for the
new location of "dir1";
5) We move the new file to some other directory. This results in updating
the log tree to included the new INODE_REF for the new location of the
file and removes the INODE_REF for the old location. This happens
during the rename when we call btrfs_log_new_name();
6) We fsync the file, and that persists the log tree changes done in the
previous step (btrfs_log_new_name() only updates the log tree in
memory);
7) We have a power failure;
8) Next time the fs is mounted, log replay happens and when processing
the inode for directory "dir1" we find a new INODE_REF and add that
link, but we don't remove the old link of the inode since we have
not logged the old parent directory of the directory inode "dir1".
As a result after log replay finishes when we trigger writeback of the
subvolume tree's extent buffers, the tree check will detect that we have
a directory a hard link count of 2 and we get a mount failure.
The errors and stack traces reported in dmesg/syslog are like this:
[ 3845.729764] BTRFS info (device dm-0): start tree-log replay
[ 3845.730304] page: refcount:3 mapcount:0 mapping:000000005c8a3027 index:0x1d00 pfn:0x11510c
[ 3845.731236] memcg:ffff9264c02f4e00
[ 3845.731751] aops:btree_aops [btrfs] ino:1
[ 3845.732300] flags: 0x17fffc00000400a(uptodate|private|writeback|node=0|zone=2|lastcpupid=0x1ffff)
[ 3845.733346] raw: 017fffc00000400a 0000000000000000 dead000000000122 ffff9264d978aea8
[ 3845.734265] raw: 0000000000001d00 ffff92650e6d4738 00000003ffffffff ffff9264c02f4e00
[ 3845.735305] page dumped because: eb page dump
[ 3845.735981] BTRFS critical (device dm-0): corrupt leaf: root=5 block=30408704 slot=6 ino=257, invalid nlink: has 2 expect no more than 1 for dir
[ 3845.737786] BTRFS info (device dm-0): leaf 30408704 gen 10 total ptrs 17 free space 14881 owner 5
[ 3845.737789] BTRFS info (device dm-0): refs 4 lock_owner 0 current 30701
[ 3845.737792] item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160
[ 3845.737794] inode generation 3 transid 9 size 16 nbytes 16384
[ 3845.737795] block group 0 mode 40755 links 1 uid 0 gid 0
[ 3845.737797] rdev 0 sequence 2 flags 0x0
[ 3845.737798] atime 1764259517.0
[ 3845.737800] ctime 1764259517.572889464
[ 3845.737801] mtime 1764259517.572889464
[ 3845.737802] otime 1764259517.0
[ 3845.737803] item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12
[ 3845.737805] index 0 name_len 2
[ 3845.737807] item 2 key (256 DIR_ITEM 2363071922) itemoff 16077 itemsize 34
[ 3845.737808] location key (257 1 0) type 2
[ 3845.737810] transid 9 data_len 0 name_len 4
[ 3845.737811] item 3 key (256 DIR_ITEM 2676584006) itemoff 16043 itemsize 34
[ 3845.737813] location key (258 1 0) type 2
[ 3845.737814] transid 9 data_len 0 name_len 4
[ 3845.737815] item 4 key (256 DIR_INDEX 2) itemoff 16009 itemsize 34
[ 3845.737816] location key (257 1 0) type 2
[ 3845.737818] transid 9 data_len 0 name_len 4
[ 3845.737819] item 5 key (256 DIR_INDEX 3) itemoff 15975 itemsize 34
[ 3845.737820] location key (258 1 0) type 2
[ 3845.737821] transid 9 data_len 0 name_len 4
[ 3845.737822] item 6 key (257 INODE_ITEM 0) itemoff 15815 itemsize 160
[ 3845.737824] inode generation 9 transid 10 size 6 nbytes 0
[ 3845.737825] block group 0 mode 40755 links 2 |
