The error branch for ext4_xattr_inode_update_ref forget to release the
refcount for iloc.bh. Find this when review code.

Fixes: 57295e835408 ("ext4: guard against EA inode refcount underflow in xattr update")
Signed-off-by: Yang Erkun <yangerkun@huawei.com>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://patch.msgid.link/20251213055706.3417529-1-yangerkun@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org

Commit 962e8a01eab9 ("ext4: introduce mext_move_extent()") attempts to
call ext4_swap_extents() on the failure path to recover the swapped
extents, but fails to acquire locks for the two inode->i_data_sem,
triggering the BUG_ON statement in ext4_swap_extents().

This issue can be fixed by calling ext4_double_down_write_data_sem()
before ext4_swap_extents().

Signed-off-by: Julian Sun <sunjunchao@bytedance.com>
Reported-by: syzbot+4ea6bd8737669b423aae@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/69368649.a70a0220.38f243.0093.GAE@google.com/
Fixes: 962e8a01eab9 ("ext4: introduce mext_move_extent()")
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Link: https://patch.msgid.link/20251208123713.1971068-1-sunjunchao@bytedance.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Pull ext4 updates from Ted Ts'o:
 "New features and improvements for the ext4 file system:
   - Optimize online defragmentation by using folios instead of
     individual buffer heads
   - Improve error codes stored in the superblock when the journal
     aborts
   - Minor cleanups and clarifications in ext4_map_blocks()
   - Add documentation of the casefold and encrypt flags
   - Add support for file systems with a blocksize greater than the
     pagesize
   - Improve performance by enabling the caching the fact that an inode
     does not have a Posix ACL

  Various Bug Fixes:
   - Fix false positive complaints from smatch
   - Fix error code which is returned by ext4fs_dirhash() when Siphash
     is used without the encryption key
   - Fix races when writing to inline data files which could trigger a
     BUG
   - Fix potential NULL dereference when there is an corrupt file system
     with an extended attribute value stored in a inode
   - Fix false positive lockdep report when syzbot uses ext4 and ocfs2
     together
   - Fix false positive reported by DEPT by adjusting lock annotation
   - Avoid a potential BUG_ON in jbd2 when a file system is massively
     corrupted
   - Fix a WARN_ON when superblock is corrupted with a non-NULL
     terminated mount options field
   - Add check if the userspace passes in a non-NULL terminated mount
     options field to EXT4_IOC_SET_TUNE_SB_PARAM
   - Fix a potential journal checksum failure whena file system is
     copied while it is mounted read-only
   - Fix a potential potential orphan file tracking error which only
     showed on 32-bit systems
   - Fix assertion checks in mballoc (which have to be explicitly enbled
     by manually enabling AGGRESSIVE_CHECKS and recompiling)
   - Avoid complaining about overly large orphan files created by mke2fs
     with with file systems with a 64k block size"

* tag 'ext4_for_linus-6.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (58 commits)
  ext4: mark inodes without acls in __ext4_iget()
  ext4: enable block size larger than page size
  ext4: add checks for large folio incompatibilities when BS > PS
  ext4: support verifying data from large folios with fs-verity
  ext4: make data=journal support large block size
  ext4: support large block size in __ext4_block_zero_page_range()
  ext4: support large block size in mpage_prepare_extent_to_map()
  ext4: support large block size in mpage_map_and_submit_buffers()
  ext4: support large block size in ext4_block_write_begin()
  ext4: support large block size in ext4_mpage_readpages()
  ext4: rename 'page' references to 'folio' in multi-block allocator
  ext4: prepare buddy cache inode for BS > PS with large folios
  ext4: support large block size in ext4_mb_init_cache()
  ext4: support large block size in ext4_mb_get_buddy_page_lock()
  ext4: support large block size in ext4_mb_load_buddy_gfp()
  ext4: add EXT4_LBLK_TO_PG and EXT4_PG_TO_LBLK for block/page conversion
  ext4: add EXT4_LBLK_TO_B macro for logical block to bytes conversion
  ext4: support large block size in ext4_readdir()
  ext4: support large block size in ext4_calculate_overhead()
  ext4: introduce s_min_folio_order for future BS > PS support
  ...

Pull superblock lock guard updates from Christian Brauner:
 "This starts the work of introducing guards for superblock related
  locks.

  Introduce super_write_guard for scoped superblock write protection.

  This provides a guard-based alternative to the manual sb_start_write()
  and sb_end_write() pattern, allowing the compiler to automatically
  handle the cleanup"

* tag 'vfs-6.19-rc1.guards' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  xfs: use super write guard in xfs_file_ioctl()
  open: use super write guard in do_ftruncate()
  btrfs: use super write guard in relocating_repair_kthread()
  ext4: use super write guard in write_mmp_block()
  btrfs: use super write guard in sb_start_write()
  btrfs: use super write guard btrfs_run_defrag_inode()
  btrfs: use super write guard in btrfs_reclaim_bgs_work()
  fs: add super_write_guard

Pull folio updates from Christian Brauner:
 "Add a new folio_next_pos() helper function that returns the file
  position of the first byte after the current folio. This is a common
  operation in filesystems when needing to know the end of the current
  folio.

  The helper is lifted from btrfs which already had its own version, and
  is now used across multiple filesystems and subsystems:
   - btrfs
   - buffer
   - ext4
   - f2fs
   - gfs2
   - iomap
   - netfs
   - xfs
   - mm

  This fixes a long-standing bug in ocfs2 on 32-bit systems with files
  larger than 2GiB. Presumably this is not a common configuration, but
  the fix is backported anyway. The other filesystems did not have bugs,
  they were just mildly inefficient.

  This also introduce uoff_t as the unsigned version of loff_t. A recent
  commit inadvertently changed a comparison from being unsigned (on
  64-bit systems) to being signed (which it had always been on 32-bit
  systems), leading to sporadic fstests failures.

  Generally file sizes are restricted to being a signed integer, but in
  places where -1 is passed to indicate "up to the end of the file", it
  is convenient to have an unsigned type to ensure comparisons are
  always unsigned regardless of architecture"

* tag 'vfs-6.19-rc1.folio' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fs: Add uoff_t
  mm: Use folio_next_pos()
  xfs: Use folio_next_pos()
  netfs: Use folio_next_pos()
  iomap: Use folio_next_pos()
  gfs2: Use folio_next_pos()
  f2fs: Use folio_next_pos()
  ext4: Use folio_next_pos()
  buffer: Use folio_next_pos()
  btrfs: Use folio_next_pos()
  filemap: Add folio_next_pos()

Pull writeback updates from Christian Brauner:
 "Features:

   - Allow file systems to increase the minimum writeback chunk size.

     The relatively low minimal writeback size of 4MiB means that
     written back inodes on rotational media are switched a lot. Besides
     introducing additional seeks, this also can lead to extreme file
     fragmentation on zoned devices when a lot of files are cached
     relative to the available writeback bandwidth.

     This adds a superblock field that allows the file system to
     override the default size, and sets it to the zone size for zoned
     XFS.

   - Add logging for slow writeback when it exceeds
     sysctl_hung_task_timeout_secs. This helps identify tasks waiting
     for a long time and pinpoint potential issues. Recording the
     starting jiffies is also useful when debugging a crashed vmcore.

   - Wake up waiting tasks when finishing the writeback of a chunk

  Cleanups:

   - filemap_* writeback interface cleanups.

     Adding filemap_fdatawrite_wbc ended up being a mistake, as all but
     the original btrfs caller should be using better high level
     interfaces instead.

     This series removes all these low-level interfaces, switches btrfs
     to a more specific interface, and cleans up other too low-level
     interfaces. With this the writeback_control that is passed to the
     writeback code is only initialized in three places.

   - Remove __filemap_fdatawrite, __filemap_fdatawrite_range, and
     filemap_fdatawrite_wbc

   - Add filemap_flush_nr helper for btrfs

   - Push struct writeback_control into start_delalloc_inodes in btrfs

   - Rename filemap_fdatawrite_range_kick to filemap_flush_range

   - Stop opencoding filemap_fdatawrite_range in 9p, ocfs2, and mm

   - Make wbc_to_tag() inline and use it in fs"

* tag 'vfs-6.19-rc1.writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
  fs: Make wbc_to_tag() inline and use it in fs.
  xfs: set s_min_writeback_pages for zoned file systems
  writeback: allow the file system to override MIN_WRITEBACK_PAGES
  writeback: cleanup writeback_chunk_size
  mm: rename filemap_fdatawrite_range_kick to filemap_flush_range
  mm: remove __filemap_fdatawrite_range
  mm: remove filemap_fdatawrite_wbc
  mm: remove __filemap_fdatawrite
  mm,btrfs: add a filemap_flush_nr helper
  btrfs: push struct writeback_control into start_delalloc_inodes
  btrfs: use the local tmp_inode variable in start_delalloc_inodes
  ocfs2: don't opencode filemap_fdatawrite_range in ocfs2_journal_submit_inode_data_buffers
  9p: don't opencode filemap_fdatawrite_range in v9fs_mmap_vm_close
  mm: don't opencode filemap_fdatawrite_range in filemap_invalidate_inode
  writeback: Add logging for slow writeback (exceeds sysctl_hung_task_timeout_secs)
  writeback: Wake up waiting tasks when finishing the writeback of a chunk.

Pull vfs inode updates from Christian Brauner:
 "Features:

   - Hide inode->i_state behind accessors. Open-coded accesses prevent
     asserting they are done correctly. One obvious aspect is locking,
     but significantly more can be checked. For example it can be
     detected when the code is clearing flags which are already missing,
     or is setting flags when it is illegal (e.g., I_FREEING when
     ->i_count > 0)

   - Provide accessors for ->i_state, converts all filesystems using
     coccinelle and manual conversions (btrfs, ceph, smb, f2fs, gfs2,
     overlayfs, nilfs2, xfs), and makes plain ->i_state access fail to
     compile

   - Rework I_NEW handling to operate without fences, simplifying the
     code after the accessor infrastructure is in place

  Cleanups:

   - Move wait_on_inode() from writeback.h to fs.h

   - Spell out fenced ->i_state accesses with explicit smp_wmb/smp_rmb
     for clarity

   - Cosmetic fixes to LRU handling

   - Push list presence check into inode_io_list_del()

   - Touch up predicts in __d_lookup_rcu()

   - ocfs2: retire ocfs2_drop_inode() and I_WILL_FREE usage

   - Assert on ->i_count in iput_final()

   - Assert ->i_lock held in __iget()

  Fixes:

   - Add missing fences to I_NEW handling"

* tag 'vfs-6.19-rc1.inode' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (22 commits)
  dcache: touch up predicts in __d_lookup_rcu()
  fs: push list presence check into inode_io_list_del()
  fs: cosmetic fixes to lru handling
  fs: rework I_NEW handling to operate without fences
  fs: make plain ->i_state access fail to compile
  xfs: use the new ->i_state accessors
  nilfs2: use the new ->i_state accessors
  overlayfs: use the new ->i_state accessors
  gfs2: use the new ->i_state accessors
  f2fs: use the new ->i_state accessors
  smb: use the new ->i_state accessors
  ceph: use the new ->i_state accessors
  btrfs: use the new ->i_state accessors
  Manual conversion to use ->i_state accessors of all places not covered by coccinelle
  Coccinelle-based conversion to use ->i_state accessors
  fs: provide accessors for ->i_state
  fs: spell out fenced ->i_state accesses with explicit smp_wmb/smp_rmb
  fs: move wait_on_inode() from writeback.h to fs.h
  fs: add missing fences to I_NEW handling
  ocfs2: retire ocfs2_drop_inode() and I_WILL_FREE usage
  ...

Mark inodes without acls with cache_no_acl() in __ext4_iget() so that
path lookup can run in RCU mode from the start. This is interesting in
particular for the case where the file owner does the lookup because in
that case end up constantly hitting the slow path otherwise. We drop out
from the fast path (because ACL state is unknown) but never end up calling
check_acl() to cache ACL state.

The problem was originally analyzed by Linus and fix tested by Matheusz,
I'm just putting it into mergeable form :).

Link: https://lore.kernel.org/all/CAHk-=whSzc75TLLPWskV0xuaHR4tpWBr=LduqhcCFr4kCmme_w@mail.gmail.com
Reported-by: Mateusz Guzik <mjguzik@gmail.com>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jan Kara <jack@suse.cz>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Message-ID: <20251125101340.24276-2-jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Since block device (See commit 3c20917120ce ("block/bdev: enable large
folio support for large logical block sizes")) and page cache (See commit
ab95d23bab220ef8 ("filemap: allocate mapping_min_order folios in the page
cache")) has the ability to have a minimum order when allocating folio,
and ext4 has supported large folio in commit 7ac67301e82f ("ext4: enable
large folio for regular file"), now add support for block_size > PAGE_SIZE
in ext4.

set_blocksize() -> bdev_validate_blocksize() already validates the block
size, so ext4_load_super() does not need to perform additional checks.
Here we only need to add the FS_LBS bit to fs_flags.

In addition, block sizes larger than the page size are currently supported
only when CONFIG_TRANSPARENT_HUGEPAGE is enabled. To make this explicit,
a blocksize_gt_pagesize entry has been added under /sys/fs/ext4/feature/,
indicating whether bs > ps is supported. This allows mke2fs to check the
interface and determine whether a warning should be issued when formatting
a filesystem with block size larger than the page size.

Suggested-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Pankaj Raghav <p.raghav@samsung.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Message-ID: <20251121090654.631996-25-libaokun@huaweicloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Supporting a block size greater than the page size (BS > PS) requires
support for large folios. However, several features (e.g., encrypt)
do not yet support large folios.

To prevent conflicts, this patch adds checks at mount time to prohibit
these features from being used when BS > PS. Since these features cannot
be changed on remount, there is no need to check on remount.

This patch adds s_max_folio_order, initialized during mount according to
filesystem features and mount options. If s_max_folio_order is 0, large
folios are disabled.

With this in place, ext4_set_inode_mapping_order() can be simplified by
checking s_max_folio_order, avoiding redundant checks.

Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>
Message-ID: <20251121090654.631996-24-libaokun@huaweicloud.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>