kernel/linux.git/fs/btrfs, branch v6.1.178

btrfs: fix incorrect buffered IO fallback for append direct writes

2026-07-24T13:55:17+00:00

[ Upstream commit ff66fe6662330226b3f486014c375538d91c44aa ] [BUG] With the previous bug of short direct writes fixed, test case generic/362 (*) still fails with the following error with nodatasum mount option: # generic/362 0s ... - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad) # - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad) # --- tests/generic/362.out 2024-08-24 15:31:37.200000000 +0930 # +++ /home/adam/xfstests/results//generic/362.out.bad 2026-05-27 10:13:09.072485767 +0930 # @@ -1,2 +1,3 @@ # QA output created by 362 # +Wrong file size after first write, got 8192 expected 4096 # Silence is golden # ... *: If the test case has been executed before with default data checksum, the failure will not reproduce. Need the following fix to make it reliably reproducible: https://lore.kernel.org/linux-btrfs/20260528111659.87113-1-wqu@suse.com/ [CAUSE] Inside btrfs_dio_iomap_begin() for a direct write, we increase the isize if it's beyond the current isize. But if the direct io finished short, we do not revert the isize to the previous value nor to the short write end. Then if we need to fall back to buffered writes, and the write has IOCB_APPEND flag, then the buffered write will be positioned at the incorrect isize. The call chain looks like this: btrfs_direct_write(pos=0, length=4K) |- __iomap_dio_rw() | |- iomap_iter() | | |- btrfs_dio_iomap_begin() | | |- btrfs_get_blocks_direct_write() | | |- i_size_write() | | Which updates the isize to the write end (4K). | | | |- iomap_dio_iter() | | Failed with -EFAULT on the first page. | | | |- iomap_iter() | | |- btrfs_dio_iomap_end() | | Detects a short write, return -ENOTBLK | |- if (ret == -ENOTBLK) { ret = 0;} | Which resets the return value. | |- ret = iomap_dio_complet() | Which returns 0. | |- btrfs_buffered_write(iocb, from); |- generic_write_checks() |- iocb->ki_pos = i_size_read() Which is still the new size (4K), other than the original isize 0. [FIX] Introduce the following btrfs_dio_data members: - old_isize - updated_isize If the direct write has enlarged the isize. Then if we got a short write, and btrfs_dio_data::updated_isize is set, revert to the correct isize based on old_isize and current file position. And here we call i_size_write() without holding an extent lock, which is a very special case that we're safe to do: - Only a single writer can be enlarging isize Enlarging isize will take the exclusive inode lock. - Buffered readers need to wait for the OE we're holding Buffered readers will lock extent and wait for OE of the folio range. Sometimes we can skip the OE wait, but since all page cache is invalidated, the OE wait can not be skipped. But I do not think this is the most elegant solution, nor covers all cases. E.g. if the bio is submitted but IO failed, we are unable to do the revert. I believe the more elegant one would be extend the EXTENT_DIO_LOCKED lifespan for direct writes, so that we can update the isize when a write beyond EOF finished successfully. However that change is too huge for a small bug fix. So only implement the minimal partial fix for now. [REASON FOR NO FIXES TAG] The bug is again very old, before commit f85781fb505e ("btrfs: switch to iomap for direct IO") we are already increasing isize without a proper rollback for short writes. Thus only a CC to stable. CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Boris Burkov Signed-off-by: Qu Wenruo Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: fix false IO failure after falling back to buffered write

2026-07-24T13:55:17+00:00

[ Upstream commit 66ff4d366e7eb4d31813d2acabf3af512ce03aa5 ] [BUG] The test case generic/362 will fail with "nodatasum" mount option (*): MOUNT_OPTIONS -- -o nodatasum /dev/mapper/test-scratch1 /mnt/scratch # generic/362 0s ... - output mismatch (see /home/adam/xfstests/results//generic/362.out.bad) # --- tests/generic/362.out 2024-08-24 15:31:37.200000000 +0930 # +++ /home/adam/xfstests/results//generic/362.out.bad 2026-05-27 10:21:17.574771567 +0930 # @@ -1,2 +1,3 @@ # QA output created by 362 # +First write failed: Input/output error # Silence is golden # ... *: If the test case has been executed before with default data checksum, the failure will not reproduce. Need the following fix to make it reliably reproducible: https://lore.kernel.org/linux-btrfs/20260528111659.87113-1-wqu@suse.com/ [CAUSE] Inside __iomap_dio_rw(), the -EFAULT/-ENOTBLK error is not directly returned. Thus we never got an error pointer from __iomap_dio_rw(). The call chain looks like this: btrfs_direct_write() |- btrfs_dio_write() |- __iomap_dio_rw() | |- iomap_iter() | | |- btrfs_dio_iomap_begin() | | Now an ordered extent is allocated for the 4K write. | | | |- iomi.status = iomap_dio_iter() | | Where iomap_dio_iter() returned -EFAULT. | | | |- ret = iomap_iter() | | |- btrfs_dio_iomap_end() | | | |- btrfs_finish_ordered_extent(uptodate = false) | | | | |- can_finish_ordered_extent() | | | | |- btrfs_mark_ordered_extent_error() | | | | |- mapping_set_error() | | | | Now the address space is marked error. | | | | return -ENOTBLK | | |- return -ENOTBLK | |- if (ret == -ENOTBLK) { ret = 0; } | Now the return value is reset to 0. | Thus no error pointer will be returned. | |- ret = iomap_dio_complete() | Since no byte is submitted, @ret is 0. | |- Fallback to buffered IO | And the buffered write finished without error | |- filemap_fdatawait_range() |- filemap_check_errors() The previous error is recorded, thus an error is returned However the buffered write is properly submitted and finished, the error is from the btrfs_finish_ordered_extent() call with @uptodate = false. [FIX] When a short dio write happened, any range that is submitted will have btrfs_extract_ordered_extent() to be called, thus the submitted range will always have an OE just covering the submitted range. The remaining OE range is never submitted, thus they should be treated as truncated, not an error. So that we can properly reclaim and not insert an unnecessary file extent item, without marking the mapping as error. Extract a helper, btrfs_mark_ordered_extent_truncated(), and utilize that helper to mark the direct IO ordered extent as truncated, so it won't cause failure for the later buffered fallback. [REASON FOR NO FIXES TAG] The bug itself is pretty old, at commit f85781fb505e ("btrfs: switch to iomap for direct IO") we're already passing @uptodate=false finishing the OE. But at that time OE with IOERR won't call mapping_set_error(), so it's not exposed. Later commit d61bec08b904 ("btrfs: mark ordered extent and inode with error if we fail to finish") finally exposed the bug, but that commit is doing a correct job, not the root cause. Anyway the bug is very old, dating back to 5.1x days, thus only CC to stable. CC: stable@vger.kernel.org # 5.15+ Reviewed-by: Boris Burkov Signed-off-by: Qu Wenruo Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: check and set EXTENT_DELALLOC_NEW before clearing EXTENT_DELALLOC

2026-07-24T13:55:17+00:00

[ Upstream commit 95ee2231896d5f2a31760411429075a99d6045a7 ] [WARNING] When running test cases with injected errors or shutdown, e.g. generic/388 or generic/475, there is a chance that the following kernel warning is triggered: BTRFS info (device dm-2): first mount of filesystem d8a19a28-3232-4809-b0df-38df83e71bff BTRFS info (device dm-2): using crc32c checksum algorithm BTRFS info (device dm-2): checking UUID tree BTRFS info (device dm-2): turning on async discard BTRFS info (device dm-2): enabling free space tree BTRFS critical (device dm-2 state E): emergency shutdown ------------[ cut here ]------------ WARNING: extent_io.c:1742 at extent_writepage_io+0x437/0x520 [btrfs], CPU#2: kworker/u43:2/651591 CPU: 2 UID: 0 PID: 651591 Comm: kworker/u43:2 Tainted: G W OE 7.0.0-rc6-custom+ #365 PREEMPT(full) 5804053f02137e627472d94b5128cc9fcb110e88 RIP: 0010:extent_writepage_io+0x437/0x520 [btrfs] Call Trace: extent_write_cache_pages+0x2a5/0x820 [btrfs 70299925d0856939e93b17d480651713b3cbba58] btrfs_writepages+0x74/0x130 [btrfs 70299925d0856939e93b17d480651713b3cbba58] do_writepages+0xd0/0x160 __writeback_single_inode+0x42/0x340 writeback_sb_inodes+0x22d/0x580 wb_writeback+0xc6/0x360 wb_workfn+0xbd/0x470 process_one_work+0x198/0x3b0 worker_thread+0x1c8/0x330 kthread+0xee/0x120 ret_from_fork+0x2a6/0x330 ret_from_fork_asm+0x11/0x20 ---[ end trace 0000000000000000 ]--- BTRFS error (device dm-2 state E): root 5 ino 259 folio 1323008 is marked dirty without notifying the fs BTRFS error (device dm-2 state E): failed to submit blocks, root=5 inode=259 folio=1323008 submit_bitmap=0: -117 BTRFS info (device dm-2 state E): last unmount of filesystem d8a19a28-3232-4809-b0df-38df83e71bff [CAUSE] Inside btrfs we have the following pattern in several locations, for example inside btrfs_dirty_folio(): btrfs_clear_extent_bit(&inode->io_tree, start_pos, end_of_last_block, EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, cached); ret = btrfs_set_extent_delalloc(inode, start_pos, end_of_last_block, extra_bits, cached); if (ret) return ret; However btrfs_set_extent_delalloc() can return IO errors other than -ENOMEM through the following callchain: btrfs_set_extent_delalloc() \- btrfs_find_new_delalloc_bytes() \- btrfs_get_extent() \- btrfs_lookup_file_extent() \- btrfs_search_slot() When such IO error happened, the previous btrfs_clear_extent_bit() has cleared the EXTENT_DELALLOC for the range, and we're expecting btrfs_set_extent_delalloc() to re-set EXTENT_DELALLOC. But since btrfs_set_extent_delalloc() failed before btrfs_set_extent_bit(), EXTENT_DELALLOC flag is no longer present. And if the folio range is dirty before entering btrfs_set_extent_delalloc(), we got a dirty folio but no EXTENT_DELALLOC flag now. Then we hit the folio writeback: extent_writepage() |- writepage_delalloc() | No ordered extent is created, as there is no EXTENT_DELALLOC set | for the folio range. | This also means the folio has no ordered flag set. | |- extent_writepage_io() \- if (unlikely(!folio_test_ordered(folio)) Now we hit the warning. [FIX] Introduce a new helper, btrfs_reset_extent_delalloc() to replace the currently open-coded btrfs_clear_extent_bit() + btrfs_set_extent_delalloc() combination. Instead of calling btrfs_clear_extent_bit() first, update EXTENT_DELALLOC_NEW first, as that part can fail due to metadata IO, meanwhile btrfs_clear_extent_bit() and btrfs_set_extent_bit() won't return any error but retry memory allocation until succeeded. This allows us to fail early without clearing EXTENT_DELALLOC bit, so even if that new btrfs_reset_extent_delalloc() failed before touching EXTENT_DELALLOC, the existing dirty range will still have their old EXTENT_DELALLOC flag present, thus avoid the warning. CC: stable@vger.kernel.org # 6.1+ Reviewed-by: Filipe Manana Signed-off-by: Qu Wenruo Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: zoned: don't account data relocation space-info in statfs free space

2026-07-24T13:54:40+00:00

[ Upstream commit 52416a27aabc43eab3792fd0ca9f5dabeab58f31 ] Don't account the free space in a data relocation space-info sub-group as usable free space in statfs. This is misleading as no user allocations can be made in this space-info sub-group. It is only a target for relocation. Fixes: f92ee31e031c ("btrfs: introduce btrfs_space_info sub-group") Reviewed-by: Boris Burkov Reviewed-by: Naohiro Aota Signed-off-by: Johannes Thumshirn Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: fix invalid pointer dereference in __btrfs_run_delayed_refs()

2026-07-24T13:54:40+00:00

[ Upstream commit 486f8298b6188ff11ef1f4be7f1d5d2e4d1b1fae ] In the beginning of the loop, we try to obtain a locked delayed ref head, if 'locked_ref' is currently NULL, by calling btrfs_select_ref_head(), which can return an error pointer. If the error pointer is -EAGAIN we do a continue and go back to the beginning of the loop, which will not try again to call btrfs_select_ref_head() since 'locked_ref' is no longer NULL but it's ERR_PTR(-EAGAIN), and then we do: spin_lock(&locked_ref->lock); against a ERR_PTR(-EAGAIN) value, generating an invalid pointer dereference. Fix this by ensuring that 'locked_ref' is set to NULL when btrfs_select_ref_head() returns ERR_PTR(-EAGAIN) and incrementing 'count' as well, to prevent infinite looping. We do this by doing a goto to the bottom of the loop that already sets 'locked_ref' to NULL and does a cond_resched(), with an increment to 'count' right before the goto. These measures were in place before the refactoring in commit 0110a4c43451 ("btrfs: refactor __btrfs_run_delayed_refs loop") but were unintentionally lost afterwards. Reported-by: Dan Carpenter Link: https://lore.kernel.org/linux-btrfs/ag8ARRwykv8bpJ87@stanley.mountain/ Fixes: 0110a4c43451 ("btrfs: refactor __btrfs_run_delayed_refs loop") Reviewed-by: Boris Burkov Reviewed-by: Qu Wenruo Signed-off-by: Filipe Manana Signed-off-by: David Sterba Signed-off-by: Sasha Levin

btrfs: do not trim a device which is not writeable

2026-07-24T13:54:28+00:00

commit 1b1937eb08f51319bf71575484cde2b8c517aedc upstream. [BUG] There is a bug report that btrfs/242 can randomly fail with the following NULL pointer dereference: run fstests btrfs/242 at 2026-06-01 10:25:08 BTRFS: device fsid d4d7f234-487c-4787-88e4-47a8b68c9874 devid 1 transid 9 /dev/sdc (8:32) scanned by mount (122609) BTRFS info (device sdc): first mount of filesystem d4d7f234-487c-4787-88e4-47a8b68c9874 BTRFS info (device sdc): using crc32c checksum algorithm BTRFS warning (device sdc): devid 2 uuid fbe72d72-3272-482d-80fb-ab88ed398192 is missing BTRFS warning (device sdc): devid 2 uuid fbe72d72-3272-482d-80fb-ab88ed398192 is missing BTRFS info (device sdc): allowing degraded mounts BTRFS info (device sdc): turning on async discard BTRFS info (device sdc): enabling free space tree Unable to handle kernel NULL pointer dereference at virtual address 0000000000000018 user pgtable: 4k pages, 48-bit VAs, pgdp=000000013fd6b000 CPU: 4 UID: 0 PID: 122625 Comm: fstrim Not tainted 7.0.10-2-default #1 PREEMPT(full) openSUSE Tumbleweed e9a5f6b24978fba3bf015a992f865837fdfff3dd Hardware name: QEMU KVM Virtual Machine, BIOS edk2-20250812-19.fc42 08/12/2025 pstate: 01400005 (nzcv daif +PAN -UAO -TCO +DIT -SSBS BTYPE=--) pc : btrfs_trim_fs+0x34c/0xa00 [btrfs] lr : btrfs_trim_fs+0x1f0/0xa00 [btrfs] Call trace: btrfs_trim_fs+0x34c/0xa00 [btrfs f02c1d570ceea621c69d302ba75dd61868083840] (P) btrfs_ioctl_fitrim+0xe8/0x178 [btrfs f02c1d570ceea621c69d302ba75dd61868083840] btrfs_ioctl+0xdd4/0x2bd8 [btrfs f02c1d570ceea621c69d302ba75dd61868083840] __arm64_sys_ioctl+0xac/0x108 invoke_syscall.constprop.0+0x5c/0xd0 el0_svc_common.constprop.0+0x40/0xf0 do_el0_svc+0x24/0x40 el0_svc+0x40/0x1d0 el0t_64_sync_handler+0xa0/0xe8 el0t_64_sync+0x1b0/0x1b8 Code: 17ffff83 f94017e0 f9002be0 f9402ea0 (f9400c00) ---[ end trace 0000000000000000 ]--- Also the reporter is very kind to test the following ASSERT() added to btrfs_trim_free_extents_throttle(): ASSERT(device->bdev, "devid=%llu path=%s dev_state=0x%lx\n", device->devid, btrfs_dev_name(device), device->dev_state); And it shows the following output: assertion failed: device->bdev, in extent-tree.c:6630 (devid=2 path=/dev/sdd dev_state=0x82) Which means the device->bdev is NULL, and the dev_state is BTRFS_DEV_STATE_IN_FS_METADATA | BTRFS_DEV_STATE_ITEM_FOUND, without BTRFS_DEV_STATE_WRITEABLE flag set. [CAUSE] The pc points to the following call chain: btrfs_trim_fs() |- btrfs_trim_free_extents() |- btrfs_trim_free_extents_throttle() |- bdev_max_discard_sectors(device->bdev) So the NULL pointer dereference is caused by device->bdev being NULL. This looks impossible by a quick glance, as just before calling btrfs_trim_free_extents_throttle(), we have skipped any device that has BTRFS_DEV_STATE_MISSING flag set. However in this particular case, there is a window where the missing device is later re-scanned, causing btrfs to remove the BTRFS_DEV_STATE_MISSING flag: btrfs_control_ioctl() |- btrfs_scan_one_device() |- device_list_add() |- rcu_assign_pointer(device->name, name); | This updates the missing device's path to the new good path. | |- clear_bit(BTRFS_DEV_STATE_MISSING, &device->dev_state) This removes the BTRFS_DEV_STATE_MISSING flag. This allows the missing device to re-appear and clear the BTRFS_DEV_STATE_MISSING flag. However the device still does not have the BTRFS_DEV_STATE_WRITEABLE flag set, nor is its bdev pointer updated. The bdev pointer remains NULL, triggering the crash later. [FIX] This is a big de-synchronization between BTRFS_DEV_STATE_MISSING and device->bdev pointer, and shows a gap in btrfs's re-appearing-device handling. The proper handling of re-appearing device will need quite some extra work, which is out of the context of this small fix. Thankfully the regular bbio submission path has already handled it well by checking if the device->bdev is NULL before submitting. So here we just fix the crash by checking if the device is writeable and has a bdev pointer before calling bdev_max_discard_sectors(). Reported-by: Su Yue Link: https://lore.kernel.org/linux-btrfs/wlwir19t.fsf@damenly.org/ Fixes: 499f377f49f0 ("btrfs: iterate over unused chunk space in FITRIM") CC: stable@vger.kernel.org # 5.10+ Reviewed-by: Filipe Manana Signed-off-by: Qu Wenruo Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman

btrfs: fix missing last_unlink_trans update when removing a directory

2026-06-19T11:37:24+00:00

[ Upstream commit 999757231c49376cd1a37308d2c8c4c9932571e1 ] When removing a directory we are not updating its last_unlink_trans field, which can result in incorrect fsync behaviour in case some one fsyncs the directory after it was removed because it's holding a file descriptor on it. Example scenario: mkdir /mnt/dir1 mkdir /mnt/dir1/dir2 mkdir /mnt/dir3 sync -f /mnt # Do some change to the directory and fsync it. chmod 700 /mnt/dir1 xfs_io -c fsync /mnt/dir1 # Move dir2 out of dir1 so that dir1 becomes empty. mv /mnt/dir1/dir2 /mnt/dir3/ open fd on /mnt/dir1 call rmdir(2) on path "/mnt/dir1" fsync fd When attempting to mount the filesystem, the log replay will fail with an -EIO error and dmesg/syslog has the following: [445771.626482] BTRFS info (device dm-0): first mount of filesystem 0368bbea-6c5e-44b5-b409-09abe496e650 [445771.626486] BTRFS info (device dm-0): using crc32c checksum algorithm [445771.627912] BTRFS info (device dm-0): start tree-log replay [445771.628335] page: refcount:2 mapcount:0 mapping:0000000061443ddc index:0x1d00 pfn:0x7072a5 [445771.629453] memcg:ffff89f400351b00 [445771.629892] aops:btree_aops [btrfs] ino:1 [445771.630737] flags: 0x17fffc00000402a(uptodate|lru|private|writeback|node=0|zone=2|lastcpupid=0x1ffff) [445771.632359] raw: 017fffc00000402a fffff47284d950c8 fffff472907b7c08 ffff89f458e412b8 [445771.633713] raw: 0000000000001d00 ffff89f6c51d1a90 00000002ffffffff ffff89f400351b00 [445771.635029] page dumped because: eb page dump [445771.635825] BTRFS critical (device dm-0): corrupt leaf: root=5 block=30408704 slot=10 ino=258, invalid nlink: has 2 expect no more than 1 for dir [445771.638088] BTRFS info (device dm-0): leaf 30408704 gen 10 total ptrs 17 free space 14878 owner 5 [445771.638091] BTRFS info (device dm-0): refs 4 lock_owner 0 current 3581087 [445771.638094] item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160 [445771.638097] inode generation 3 transid 9 size 16 nbytes 16384 [445771.638098] block group 0 mode 40755 links 1 uid 0 gid 0 [445771.638100] rdev 0 sequence 2 flags 0x0 [445771.638102] atime 1775744884.0 [445771.660056] ctime 1775744885.645502983 [445771.660058] mtime 1775744885.645502983 [445771.660060] otime 1775744884.0 [445771.660062] item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12 [445771.660064] index 0 name_len 2 [445771.660066] item 2 key (256 DIR_ITEM 1843588421) itemoff 16077 itemsize 34 [445771.660068] location key (259 1 0) type 2 [445771.660070] transid 9 data_len 0 name_len 4 [445771.660075] item 3 key (256 DIR_ITEM 2363071922) itemoff 16043 itemsize 34 [445771.660076] location key (257 1 0) type 2 [445771.660077] transid 9 data_len 0 name_len 4 [445771.660078] item 4 key (256 DIR_INDEX 2) itemoff 16009 itemsize 34 [445771.660079] location key (257 1 0) type 2 [445771.660080] transid 9 data_len 0 name_len 4 [445771.660081] item 5 key (256 DIR_INDEX 3) itemoff 15975 itemsize 34 [445771.660082] location key (259 1 0) type 2 [445771.660083] transid 9 data_len 0 name_len 4 [445771.660084] item 6 key (257 INODE_ITEM 0) itemoff 15815 itemsize 160 [445771.660086] inode generation 9 transid 9 size 8 nbytes 0 [445771.660087] block group 0 mode 40777 links 1 uid 0 gid 0 [445771.660088] rdev 0 sequence 2 flags 0x0 [445771.660089] atime 1775744885.641174097 [445771.660090] ctime 1775744885.645502983 [445771.660091] mtime 1775744885.645502983 [445771.660105] otime 1775744885.641174097 [445771.660106] item 7 key (257 INODE_REF 256) itemoff 15801 itemsize 14 [445771.660107] index 2 name_len 4 [445771.660108] item 8 key (257 DIR_ITEM 2676584006) itemoff 15767 itemsize 34 [445771.660109] location key (258 1 0) type 2 [445771.660110] transid 9 data_len 0 name_len 4 [445771.660111] item 9 key (257 DIR_INDEX 2) itemoff 15733 itemsize 34 [445771.660112] location key (258 1 0) type 2 [445771.660113] transid 9 data_len 0 name_len 4 [445771.660114] item 10 key (258 INODE_ITEM 0) itemoff 15573 itemsize 160 [445771.660115] inode generation 9 transid 10 size 0 nbytes 0 [445771.660116] block group 0 mode 40755 links 2 uid 0 gid 0 [445771.660117] rdev 0 sequence 0 flags 0x0 [445771.660118] atime 1775744885.645502983 [445771.660119] ctime 1775744885.645502983 [445771.660120] mtime 1775744885.645502983 [445771.660121] otime 1775744885.645502983 [445771.660122] item 11 key (258 INODE_REF 257) itemoff 15559 itemsize 14 [445771.660123] index 2 name_len 4 [445771.660124] item 12 key (258 INODE_REF 259) itemoff 15545 itemsize 14 [445771.660125] index 2 name_len 4 [445771.660126] item 13 key (259 INODE_ITEM 0) itemoff 15385 itemsize 160 [445771.660127] inode generation 9 transid 10 size 8 nbytes 0 [445771.660128] block group 0 mode 40755 links 1 uid 0 gid 0 [445771.660129] rdev 0 sequence 1 flags 0x0 [445771.660130] atime 1775744885.645502983 [445771.660130] ctime 1775744885.645502983 [445771.660131] mtime 1775744885.645502983 [445771.660132] otime 1775744885.645502983 [445771.660133] item 14 key (259 INODE_REF 256) itemoff 15371 itemsize 14 [445771.660134] index 3 name_len 4 [445771.660135] item 15 key (259 DIR_ITEM 2676584006) itemoff 15337 itemsize 34 [445771.660136] location key (258 1 0) type 2 [445771.660137] transid 10 data_len 0 name_len 4 [445771.660138] item 16 key (259 DIR_INDEX 2) itemoff 15303 itemsize 34 [445771.660139] location key (258 1 0) type 2 [445771.660140] transid 10 data_len 0 name_len 4 [445771.660144] BTRFS error (device dm-0): block=30408704 write time tree block corruption detected [445771.661650] ------------[ cut here ]------------ [445771.662358] WARNING: fs/btrfs/disk-io.c:326 at btree_csum_one_bio+0x217/0x230 [btrfs], CPU#8: mount/3581087 [445771.663588] Modules linked in: btrfs f2fs xfs (...) [445771.671229] CPU: 8 UID: 0 PID: 3581087 Comm: mount Tainted: G W 7.0.0-rc6-btrfs-next-230+ #2 PREEMPT(full) [445771.672575] Tainted: [W]=WARN [445771.672987] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-0-gea1b7a073390-prebuilt.qemu.org 04/01/2014 [445771.674460] RIP: 0010:btree_csum_one_bio+0x217/0x230 [btrfs] [445771.675222] Code: 89 44 24 (...) [445771.677364] RSP: 0018:ffffd23882247660 EFLAGS: 00010246 [445771.678029] RAX: 0000000000000000 RBX: ffff89f6c51d1a90 RCX: 0000000000000000 [445771.678975] RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff89f406020000 [445771.679983] RBP: ffff89f821204000 R08: 0000000000000000 R09: 00000000ffefffff [445771.680905] R10: ffffd23882247448 R11: 0000000000000003 R12: ffffd23882247668 [445771.681978] R13: ffff89f458e40fc0 R14: ffff89f737f4f500 R15: ffff89f737f4f500 [445771.682912] FS: 00007f0447a98840(0000) GS:ffff89fb9771d000(0000) knlGS:0000000000000000 [445771.684393] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [445771.685230] CR2: 00007f0447bf1330 CR3: 000000017cb02002 CR4: 0000000000370ef0 [445771.686273] Call Trace: [445771.686646] [445771.686969] btrfs_submit_bbio+0x83f/0x860 [btrfs] [445771.687750] ? write_one_eb+0x28f/0x340 [btrfs] [445771.688428] btree_writepages+0x2e3/0x550 [btrfs] [445771.689180] ? kmem_cache_alloc_noprof+0x12a/0x490 [445771.689963] ? alloc_extent_state+0x19/0x120 [btrfs] [445771.690801] ? kmem_cache_free+0x135/0x380 [445771.691328] ? preempt_count_add+0x69/0xa0 [445771.691831] ? set_extent_bit+0x252/0x8e0 [btrfs] [445771.692468] ? xas_load+0x9/0xc0 [445771.692873] ? xas_find+0x14d/0x1a0 [445771.693304] do_writepages+0xc6/0x160 [445771.693756] filemap_writeback+0xb8/0xe0 [445771.694274] btrfs_write_marked_extents+0x61/0x170 [btrfs] [445771.694999] btrfs_write_and_wait_transaction+0x4e/0xc0 [btrfs] [445771.695818] btrfs_commit_transaction+0x5c8/0xd10 [btrfs] [445771.696530] ? kmem_cache_free+0x135/0x380 [445771.697120] ? release_extent_buffer+0x34/0x160 [btrfs] [445771.697786] btrfs_recover_log_trees+0x7be/0x7e0 [btrfs] [445771.698525] ? __pfx_replay_one_buffer+0x10/0x10 [btrfs] [445771.699206] open_ctree+0x11e5/0x1810 [btrfs] [445771.699776] btrfs_get_tree.cold+0xb/0x162 [btrfs] [445771.700463] ? fscontext_read+0x165/0x180 [445771.701146] ? rw_verify_area+0x50/0x180 [445771.701866] vfs_get_tree+0x25/0xd0 [445771.702491] vfs_cmd_create+0x59/0xe0 [445771.703125] __do_sys_fsconfig+0x303/0x610 [445771.703603] do_syscall_64+0xe9/0xf20 [445771.703974] entry_SYSCALL_64_after_hwframe+0x76/0x7e [445771.704700] RIP: 0033:0x7f0447cbd4aa [445771.705108] Code: 73 01 c3 (...) [445771.707263] RSP: 002b:00007ffc4e528318 EFLAGS: 00000246 ORIG_RAX: 00000000000001af [445771.708107] RAX: ffffffffffffffda RBX: 00005561585d8c20 RCX: 00007f0447cbd4aa [445771.708931] RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000003 [445771.709744] RBP: 00005561585d9120 R08: 0000000000000000 R09: 0000000000000000 [445771.710674] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [445771.711477] R13: 00007f0447e4f580 R14: 00007f0447e5126c R15: 00007f0447e36a23 [445771.712277] [445771.712541] ---[ end trace 0000000000000000 ]--- [445771.713382] BTRFS error (device dm-0): error while writing out transaction: -5 [445771.714679] BTRFS warning (device dm-0): Skipping commit of aborted transaction. [445771.715562] BTRFS error (device dm-0 state A): Transaction aborted (error -5) [445771.716459] BTRFS: error (device dm-0 state A) in cleanup_transaction:2068: errno=-5 IO failure [445771.717936] BTRFS error (device dm-0 state EA): failed to recover log trees with error: -5 [445771.719681] BTRFS error (device dm-0 state EA): open_ctree failed: -5 The problem is that such a fsync should have result in a fallback to a transaction commit, but that did not happen because through the btrfs_rmdir() we never update the directory's last_unlink_trans field. Any inode that had a link removed must have its last_unlink_trans updated to the ID of transaction used for the operation, otherwise fsync and log replay will not work correctly. btrfs_rmdir() calls btrfs_unlink_inode() and through that call chain we never call btrfs_record_unlink_dir() in order to update last_unlink_trans. However btrfs_unlink(), which is used for unlinking regular files, calls btrfs_record_unlink_dir() and then calls btrfs_unlink_inode(). So fix this by moving the call to btrfs_record_unlink_dir() from btrfs_unlink() to btrfs_unlink_inode(). A test case for fstests will follow soon. Reported-by: Slava0135 Link: https://lore.kernel.org/linux-btrfs/CAAJYhww5ov62Hm+n+tmhcL-e_4cBobg+OWogKjOJxVUXivC=MQ@mail.gmail.com/ CC: stable@vger.kernel.org Signed-off-by: Filipe Manana Signed-off-by: David Sterba [ wrapped dir and inode arguments with BTRFS_I() since 6.1 btrfs_rmdir() uses struct inode * instead of struct btrfs_inode * ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: fix double free in create_space_info_sub_group() error path

2026-06-19T11:37:24+00:00

[ Upstream commit a7449edf96143f192606ec8647e3167e1ecbd728 ] When kobject_init_and_add() fails, the call chain is: create_space_info_sub_group() -> btrfs_sysfs_add_space_info_type() -> kobject_init_and_add() -> failure -> kobject_put(&sub_group->kobj) -> space_info_release() -> kfree(sub_group) Then control returns to create_space_info_sub_group(), where: btrfs_sysfs_add_space_info_type() returns error -> kfree(sub_group) Thus, sub_group is freed twice. Keep parent->sub_group[index] = NULL for the failure path, but after btrfs_sysfs_add_space_info_type() has called kobject_put(), let the kobject release callback handle the cleanup. Fixes: f92ee31e031c ("btrfs: introduce btrfs_space_info sub-group") CC: stable@vger.kernel.org # 6.18+ Reviewed-by: Qu Wenruo Signed-off-by: Guangshuo Li Signed-off-by: David Sterba Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: remove fs_info argument from btrfs_sysfs_add_space_info_type()

2026-06-19T11:37:24+00:00

[ Upstream commit 771af6ff72e0ed0eb8bf97e5ae4fa5094e0c5d1d ] We don't need it since we can grab fs_info from the given space_info. So remove the fs_info argument. Reviewed-by: Johannes Thumshirn Signed-off-by: Filipe Manana Reviewed-by: David Sterba Signed-off-by: David Sterba Stable-dep-of: a7449edf9614 ("btrfs: fix double free in create_space_info_sub_group() error path") Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

btrfs: fix btrfs_ioctl_space_info() slot_count TOCTOU which can lead to info-leak

2026-06-19T11:37:24+00:00

[ Upstream commit 973e57c726c1f8e77259d1c8e519519f1e9aea77 ] btrfs_ioctl_space_info() has a TOCTOU race between two passes over the block group RAID type lists. The first pass counts entries to determine the allocation size, then the second pass fills the buffer. The groups_sem rwlock is released between passes, allowing concurrent block group removal to reduce the entry count. When the second pass fills fewer entries than the first pass counted, copy_to_user() copies the full alloc_size bytes including trailing uninitialized kmalloc bytes to userspace. Fix by copying only total_spaces entries (the actually-filled count from the second pass) instead of alloc_size bytes, and switch to kzalloc so any future copy size mismatch cannot leak heap data. Fixes: 7fde62bffb57 ("Btrfs: buffer results in the space_info ioctl") CC: stable@vger.kernel.org # 3.0 Signed-off-by: Yochai Eisenrich Reviewed-by: David Sterba Signed-off-by: David Sterba [ adapted upstream's `return -EFAULT;` to stable's `ret = -EFAULT;` fall-through to existing `out:` cleanup label ] Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman